title stringlengths 0 1.13k | abstract stringlengths 1 15.7k | PMID int64 22 36.5M |
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A restoratively driven ridge categorization, as determined by incorporating ideal restorative positions on radiographic templates utilizing computed tomography scan analysis. | The introduction of implants into the field of dentistry has revolutionized the way we evaluate edentulous ridges. In an attempt to evaluate the deficient edentulous ridge, numerous classification systems have been proposed. Each of these classification systems implements a different approach for evaluating and planning treatment for the ridge deficiency. The purpose of the present investigation was to propose a restoratively driven ridge categorization (RDRC) for horizontal ridge deformities based on an ideal implant position as determined through implant simulation, utilizing computed tomography (CT) scan images. Radiographic templates were developed to capture the ideal restorative tooth position. Measurements were performed using CT scan software in a cross-sectional view and by virtual placement of a parallel-sided implant with a 3.25-mm diameter. Edentulous ridges were divided into five groupings: Group I, simulated implants with at least 2 mm of facial bone, accounted for 19.4% of ridges; Group II, simulated implant completely surrounded by bone, with less than 2 mm of facial plate thickness, accounted for 10.4% of ridges; Group III, wherein dehiscences are detected but no fenestrations are present, accounted for 33.3% of ridges; Group IV, wherein fenestrations are detected but no dehiscence is present, accounted for 6.3% of ridges; and Group V, wherein both dehiscences and fenestrations are present, accounted for 30.6% of ridges. The use of RDRC indicates that a high number of cases in the maxillary anterior area would require augmentation procedures in order to achieve ideal implant placement and restoration. | 18,783,410 |
Alveolar ridge regeneration with equine spongy bone: a clinical, histological, and immunohistochemical case series. | In the case of localized ridge atrophy, a ridge augmentation procedure, with the use of bone substitutes and barrier membranes, may then be necessary. The aim of the present study was a clinical, histological, and immunohistochemical evaluation of an equine spongy bone in alveolar ridge augmentation procedures. Five patients showing horizontal mandibular ridge defects participated in this study. A ridge augmentation was performed through an onlay apposition of equine bone covered by a titanium-reinforced membrane. After 6 months of healing, five bone cores from nonaugmented sites (control) and five from augmented sites (test) were retrieved. In test sites, no postoperative complications occurred. Horizontal bone width increased from 24 to 37 mm. In control sites, the newly formed bone represented 33%, and in test sites, 35% of the total area. The mean value of the microvessel density was 25.6 +/- 3.425 per mm(2) in controls, while 33.3 +/- 2.5 vessels per mm(2) in the test sites were found (p < .05). Both groups showed a high intensity (++) of vascular endothelial growth factor expression in the newly formed bone, while a low intensity (+) was found in the mature bone. Equine bone appeared to be biocompatible and to be associated with new vessel ingrowth. Within the limits of the small sample size, the present study indicated that equine bone could be used in mandibular ridge augmentations. | 18,783,426 |
Cerebral MRI abnormalities associated with vigabatrin therapy. | Investigate whether patients on vigabatrin demonstrated new-onset and reversible T(2)-weighted magnetic resonance imaging (MRI) abnormalities. MRI of patients treated during vigabatrin therapy was reviewed, following detection of new basal ganglia, thalamus, and corpus callosum hyperintensities in an infant treated for infantile spasms. Patients were assessed for age at time of MRI, diagnosis, duration, and dose, MRI findings pre-, on, and postvigabatrin, concomitant medications, and clinical correlation. These findings were compared to MRI in patients with infantile spasms who did not receive vigabatrin. Twenty-three patients were identified as having MRI during the course of vigabatrin therapy. After excluding the index case, we detected new and reversible basal ganglia, thalamic, brainstem, or dentate nucleus abnormalities in 7 of 22 (32%) patients treated with vigabatrin. All findings were reversible following discontinuation of therapy. Diffusion-weighted imaging (DWI) was positive with apparent diffusion coefficient (ADC) maps demonstrating restricted diffusion. Affected versus unaffected patients, respectively, had a median age of 11 months versus 5 years, therapy duration 3 months versus 12 months, and dosage 170 mg/kg/day versus 87 mg/kg/day. All affected patients were treated for infantile spasms; none of 56 patients with infantile spasms who were not treated with vigabatrin showed the same abnormalities. MRI abnormalities attributable to vigabatrin, characterized by new-onset and reversible T(2)-weighted hyperintensities and restricted diffusion in thalami, globus pallidus, dentate nuclei, brainstem, or corpus callosum were identified in 8 of 23 patients. Young age and relatively high dose appear to be risk factors. | 18,783,433 |
Diversity of Sinorhizobium strains nodulating Medicago sativa from different Iranian regions. | Alfalfa is believed to have originated in north-western Iran and has a long history of coexistence with its bacterial symbiont Sinorhizobium in soils of Iran. However, little is known about the diversity of Sinorhizobium strains nodulating Iranian alfalfa genotypes. In this study, Sinorhizobium populations were sampled from eight different Iranian sites using three cultivars of Medicago sativa as trap host plants. A total of 982 rhizobial strains were isolated and species were identified showing a large prevalence of Sinorhizobium meliloti over Sinorhizobium medicae. Analysis of salt tolerance demonstrated a great phenotypic diversity. The genetic diversity of the Sinorhizobium isolates was analysed using BOX-PCR and enterobacterial repetitive intergenic consensus (ERIC)-PCR. Patterns ofBOX-PCR fingerprinting were statistically analysed with AMOVA to evaluate the role of plant variety and site of origin in the genetic variance observed. Results indicated that most of the total molecular variance was attributable to divergence among strains isolated from different sites and cultivars (intrapopulation, strain-by-strain variance). Moreover, the analysis showed the presence of two geographic populations (west and northwest), indicating that the effect of the site of origin could be more relevant in shaping population genetic diversity than the effect of cultivar or individual plant. | 18,783,438 |
Haemophilia A: patients' knowledge level of treatment and sources of treatment-related information. | There are minimal or no data regarding the extent of patient and/or parent/legal guardian/caregiver knowledge about haemophilia A and its treatment, their sources for this information, or their preferred methods of communication. A pilot study using a survey instrument developed by haemophilia nurse coordinators was conducted at a national meeting to obtain information on these topics. A total of 187 surveys were completed. More than 80% of respondents reported high and high-medium knowledge levels about how haemophilia A is inherited, types of bleeding, identifying and treating bleeding emergencies, prophylaxis and on-demand treatment, travel and vacation planning and guidelines for exercise and sports activities. However, a lower proportion of respondents (<65%) reported high and high-medium knowledge levels for drug-related topics. The majority of respondents (>55%) consistently ranked healthcare providers as the most useful source of information for most topics related to haemophilia A. This pilot survey of well-informed respondents identified deficits in knowledge regarding factor concentrates for the treatment of haemophilia A and highlights the need for healthcare providers to provide more information about factor concentrates, insurance coverage for treatments, and community and educational resources. Additional study is necessary to determine the extent of knowledge deficits and how best to address them in the haemophilia A population as a whole. Other areas of study needed are whether information deficits and delivery of information vary by age or by other factors. | 18,783,441 |
Unilateral or "side-locked" migrainous headache with autonomic symptoms linked to night guard use. | Night guards are commonly prescribed as a palliative measure for bruxism, temporomandibular joint symptoms, and associated disorders. We describe a patient with a 10- to 12-year history of night guard use with concurrent unilateral side-locked migrainous headaches with autonomic symptoms characteristic of trigeminal autonomic cephalgia. These headaches were refractory to numerous pharmacological interventions. Upon self-initiated cessation of night guard use, there was complete remission of headaches. We believe the headaches were initiated by night guard-initiated irritation of the trigeminal nerve and a trigeminal autonomic reflex resulting in unilateral migrainous headache with autonomic signs. | 18,783,445 |
Serum concentrations of s100b and NSE in migraine. | The protein s100b indicates astrocytal damage as well as dysfunction of the blood-brain barrier (BBB), and neuron-specific enolase (NSE) is regarded as a marker for neuronal cell loss. Recently, s100b was shown to be a potentially useful marker for migraine in children. In this study, we investigated the levels of s100b and NSE in adult migraineurs during and after migraine attacks in order to gain some more insight into migraine pathophysiology. Serum levels of s100b and NSE were measured in 21 migraineurs and compared with 21 healthy subjects matched by sex and age. In migraineurs, blood samples were taken during a migraine attack and following a pain-free period of 2-4 days. During migraine attacks elevated s100b levels could be observed. Maximal concentrations were detected in the pain-free period after 2-4 days. Regarding NSE, serum levels were decreased slightly during and after migraine bouts. Our data suggest a prolonged disruption of BBB during and after migraine attacks. Other possible explanations concerning the detected serum levels of s100b and NSE will be discussed; however, neuronal cell death can be ruled out by the decreased serum concentrations of NSE. With regard to the results of the present study, further research is necessary to evaluate the role of s100b and NSE in migraine. | 18,783,450 |
Persistence of HMO performance measures. | To simplify the decision-making process, we propose and implement an approach to assess the stability of health plan performance over time when multiple indicators of performance exist. National Committee for Quality Assurance Health Care Effectiveness Data and Information Set data for childhood immunization for both publicly and non-publicly reporting health plans between 1998 and 2002. DATA/STUDY DESIGN: We use longitudinal data to examine whether plan quality ratings are stable from year to year. We estimate a parametric Multiple Indicator Multiple Cause Model, a model which allows us to aggregate the multiple measures of performance. The model controls for observed characteristics of the plan and market, allowing for unmeasured heterogeneity. We find moderate persistence in plan performance over time. A plan in the upper tier of performance in the year 1999 has only a 0.47 probability of remaining in the upper tier in the year 2001. Multiple years of good performance increase the probability of good performance in the future. For example, from the subset of plans in the upper tier of performance in 1999, 63 percent continued to perform in the upper tier in 2000. However, from the subset of plans in the upper tier in both 1998 and 1999, about three-fourths of the plans continued to perform in the upper tier in the year 2000. Finally, better performance in the more recent past is more indicative of better performance in the future than better performance in the more distant past. Although there is some persistence in health plan ratings over time, it is not uncommon for ratings of plans to change between when the data are generated and when actions based on that data, such as employers' contracting decisions or consumers' enrollment decisions, may take effect. Decision makers should be cognizant of this issue and methods should be developed to mitigate its consequences. | 18,783,460 |
Low PAI-1 activity in relation to inflammatory parameters, insulin profile and body mass index. | High plasminogen activator inhibitor type 1 (PAI-1) activity is associated with inflammatory reactions and insulin resistance, but it is unclear what regulates PAI-1 activity at the low end. The purpose of this study was to investigate if patients with low PAI-1 activity have a lack of inflammatory response or a low insulin level. Retrospective cohort study with internal controls. Sixty-three patients referred for investigation of bleeding tendency and with low PAI-1 activity were compared with 118 patients with normal or high PAI-1 activity. Levels of C-peptide, proinsulin, high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6). Adjustments were made for body mass index (BMI), oral oestrogens and age. Low PAI-1 activity was defined as less than 1 U mL(-1). Body mass index in the low normal range, oral oestrogens, young age and low C-peptide were significantly associated with low PAI-1 activity and there was a trend for association with IL-6 in univariable analysis. The effect of age disappeared after correction for oral oestrogens and the effect of C-peptide and IL-6 disappeared after further adjustments. Low BMI remained as the strongest predictor of low PAI-1 activity. Patients with bleeding tendency and low PAI-1 activity have inflammatory and insulin profiles similar to those with normal or high PAI-1, whereas BMI seems to be the most important determinant. | 18,783,478 |
Pathogenesis of Helicobacter pylori infection. | The clinical outcome of Helicobacter pylori infection is determined by a complex scenario of interactions between the bacterium and the host. The main bacterial factors associated with colonization and pathogenicity comprise outer membrane proteins including BabA, SabA, OipA, AlpA/B, as well as the virulence factors CagA in the cag pathogenicity island (cagPAI) and the vacuolating cytotoxin VacA. The multitude of these proteins and allelic variation makes it extremely difficult to test the contribution of each individual factor. Much effort has been put into identifying the mechanism associated with H. pylori-associated carcinogenesis. Interaction between bacterial factors such as CagA and host signal transduction pathways seems to be critical for mediating the induction of membrane dynamics, actin-cytoskeletal rearrangements and the disruption of cell-to-cell junctions as well as proliferative, pro-inflammatory and antiapoptotic nuclear responses. An animal model using the Mongolian gerbil is a useful system to study the gastric pathology of H. pylori infection. | 18,783,516 |
The advantages of topical combination therapy in the treatment of inflammatory dermatomycoses. | Dermatomycoses are contagious superficial fungal infections, which are highly prevalent in developed and developing countries. Caused by a range of Epidermophyton, Microsporum and Trichophyton species, dermatomycoses manifest on glabrous skin as 'ringworm', an annular scaly lesion with a variable inflammatory component. Itch is the chief subjective symptom, particularly in tinea cruris. Unless lesions are extensive or resistant to local therapy, dermatomycoses of glabrous skin are treated with topical antifungal agents, such as imidazoles and allylamines. Studies show, however, that the addition of a topical corticosteroid to imidazole therapy increases the bioavailability and prolongs the activity of the antimycotic, while rapidly reducing inflammatory symptoms. Travocort is a combination of 1% isoconazole nitrate (ISN), a broad-spectrum imidazole with established antimicrobial activity and antimycotic efficacy, and 0.1% diflucortolone valerate (DFV), a potent topical corticosteroid with low systemic absorption and therefore a low risk of systemic glucocorticoid side-effects. In randomised, double-blind controlled clinical trials, Travocort therapy showed a more rapid onset of action, faster relief of itch and other inflammatory symptoms, improved overall therapeutic benefits and better mycological cure rate during the first 2 weeks of treatment compared with ISN monotherapy. Travocort is well tolerated and, because of prolonged ISN retention in the skin, provides antifungal protection against reinfection for some weeks after therapy. | 18,783,560 |
Association between H-RAS T81C genetic polymorphism and gastrointestinal cancer risk: a population based case-control study in China. | Gastrointestinal cancer, such as gastric, colon and rectal cancer, is a major medical and economic burden worldwide. However, the exact mechanism of gastrointestinal cancer development still remains unclear. RAS genes have been elucidated as major participants in the development and progression of a series of human tumours and the single nucleotide polymorphism at H-RAS cDNA position 81 was demonstrated to contribute to the risks of bladder, oral and thyroid carcinoma. Therefore, we hypothesized that this polymorphisms in H-RAS could influence susceptibility to gastrointestinal cancer as well, and we conducted this study to test the hypothesis in Chinese population. A population based case-control study, including 296 cases with gastrointestinal cancer and 448 healthy controls selected from a Chinese population was conducted. H-RAS T81C polymorphism was genotyped by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) assay. In the healthy controls, the TT, TC and CC genotypes frequencies of H-RAS T81C polymorphism, were 79.24%, 19.87% and 0.89%, respectively, and the C allele frequency was 10.83%. Compared with TT genotype, the TC genotype was significantly associated with an increased risk of gastric cancer (adjusted OR = 3.67, 95%CI = 2.21-6.08), while the CC genotype showed an increased risk as well (adjusted OR = 3.29, 95%CI = 0.54-19.86), but it was not statistically significant. In contrast, the frequency of TC genotype was not significantly increased in colon cancer and rectal cancer patients. Further analysis was performed by combining TC and CC genotypes compared against TT genotype. As a result, a statistically significant risk with adjusted OR of 3.65 (95%CI, 2.22-6.00) was found in gastric cancer, while no significant association of H-RAS T81C polymorphism with colon cancer and rectal cancer was observed. These findings indicate, for the first time, that there is an H-RAS T81C polymorphism existing in Chinese population, and this SNP might be a low penetrance gene predisposition factor for gastric cancer. | 18,783,589 |
LOMA: a fast method to generate efficient tagged-random primers despite amplification bias of random PCR on pathogens. | Pathogen detection using DNA microarrays has the potential to become a fast and comprehensive diagnostics tool. However, since pathogen detection chips currently utilize random primers rather than specific primers for the RT-PCR step, bias inherent in random PCR amplification becomes a serious problem that causes large inaccuracies in hybridization signals. In this paper, we study how the efficiency of random PCR amplification affects hybridization signals. We describe a model that predicts the amplification efficiency of a given random primer on a target viral genome. The prediction allows us to filter false-negative probes of the genome that lie in regions of poor random PCR amplification and improves the accuracy of pathogen detection. Subsequently, we propose LOMA, an algorithm to generate random primers that have good amplification efficiency. Wet-lab validation showed that the generated random primers improve the amplification efficiency significantly. The blind use of a random primer with attached universal tag (random-tagged primer) in a PCR reaction on a pathogen sample may not lead to a successful amplification. Thus, the design of random-tagged primers is an important consideration when performing PCR. | 18,783,594 |
Validity of a self-reported measure of familial history of obesity. | Familial history information could be useful in clinical practice. However, little is known about the accuracy of self-reported familial history, particularly self-reported familial history of obesity (FHO). Two cross-sectional studies were conducted. The aims of study 1 was to compare self-reported and objectively measured weight and height whereas the aims of study 2 were to examine the relationship between the weight and height estimations reported by the study participants and the values provided by their family members as well as the validity of a self-reported measure of FHO. Study 1 was conducted between 2004 and 2006 among 617 subjects and study 2 was conducted in 2006 among 78 participants. In both studies, weight and height reported by the participants were significantly correlated with their measured values (study 1: r = 0.98 and 0.98; study 2: r = 0.99 and 0.97 respectively; p < 0.0001). Estimates of weight and height for family members provided by the study participants were strongly correlated with values reported by each family member (r = 0.96 and 0.95, respectively; p < 0.0001). Substantial agreement between the FHO reported by the participants and the one obtained by calculating the BMI of each family members was observed (kappa = 0.72; p < 0.0001). Sensitivity (90.5%), specificity (82.6%), positive (82.6%) and negative (90.5%) predictive values of FHO were very good. A self-reported measure of FHO is valid, suggesting that individuals are able to detect the presence or the absence of obesity in their first-degree family members. | 18,783,616 |
Acknowledging and adapting to dietetic students' changing needs. | Various societal influences have shaped the way dietetic students view and react to current educational situations. Students' perspectives were sought on conditions that caused stress in the educational environment, what they thought educators did not understand about them, and changes their faculty or preceptors had made to address their needs. Third- and fourth-year university students, interns in their final rotations, and master's degree students completed a questionnaire (n=284). Several stressors were identified: thinking about getting a job as a dietitian, lack of finances or debt, competing for internship positions, the ability to meet program demands, and envisioning the area in which they would specialize. The qualitative analysis highlighted gaps in understanding between students and educators. Gaps concerned student finances, the evaluation process, inflexible undergraduate and internship structures, competition among students, ineffective communication, and finding a balance between academics and other competing interests. A conflict exists between what students expect as part of their educational experience and what they actually experience. Students appreciated educators who engaged them in the learning process and recognized the realities of their lives. | 18,783,637 |
[Biostatistics: a fundamental tool for the elaboration of radiological articles]. | Biostatistics has become an indispensable tool in all domains of the Health Sciences. Biostatistics is essential for ensuring valid decision making, and knowing the basic principles of biostatistics well will enable us to use this tool correctly. In this article, first biostatistics is defined and then its use and justification are discussed. The aim is to go through all of the steps that should be followed in the entire research process, beginning with specifying the objective of the study, approaching different study designs (cross-sectional, prospective and retrospective longitudinal, clinical trials) and the most commonly used statistical techniques in the Health Sciences, from descriptive statistics necessary to begin any study, to univariate analysis of both qualitative and quantitative variables, to the multivariate analyses most commonly used in our field. | 18,783,646 |
[Femoroacetabular impingement: radiographic diagnosis--what the radiologist should know]. | The purpose of this article is to show the important radiographic criteria that indicate the two types of femoroacetabular impingement: pincer and cam impingement. In addition, potential pitfalls in pelvic imaging concerning femoroacetabular impingement are shown. Femoroacetabular impingement is a major cause for early "primary" osteoarthritis of the hip. It can easily be recognized on conventional radiographs of the pelvis and the proximal femur. | 18,783,647 |
[Useful tips for CT-angiography]. | Multidetector CT scanners are now available in most hospitals; this technology makes it possible to perform cardiac studies. The technique depends on the technology, and certain points must be taken into consideration to improve the results of cardiac studies. We discuss four key points for ensuring high-quality multidetector CT studies. Under the heading patient preparation, we include deciding whether to use beta blockers, aspects related to the routine use of vasodilators, some guidelines for patient breath holding, etc. The next section discusses imaging acquisition, including when to use multisegmentation or even the possibility of prospective acquisition to reduce the dose of radiation. The third point deals with contrast administration to achieve good enhancement of the vessels. The last section reviews postprocessing techniques and comments on possible errors in 3D reconstructions or the need to render reconstructions of the entire thorax to rule out other diseases. | 18,783,648 |
[The pharmacokinetics of metronidazole and gentamicin in a single preoperative dose as antibiotic prophylaxis in colorectal surgery]. | To describe, in patients undergoing colorectal surgery (CRS), the pharmacokinetics of a single, prophylactic preoperative dose of 1,500 mg of metronidazole plus 240 mg gentamicin and measure its efficacy in accordance with the accepted pharmacodynamic and microbiological parameters. Thirty-six patients undergoing CRS agreed to participate in the study. Three blood samples were taken from each. Cmax 15 minutes after finishing the infusion of the mixture, CfinIQ on finishing the surgery, and Cmin between 12 and 24 hours post-administration. The concentrations of metronidazole and gentamicin in each simple were measured and the pharmacokinetic parameters were estimated (dV- distribution volume , Cl-plasma clearance). For the metronidazole, concentrations in excess of 8 microg/ml were considered effective, and for gentamicin, C(max) in excess of 9 microg/ml and inhibition quotients above 8. All the concentrations of metronidazole, both CmaxMTZ and CfinIQMTZ were above 8 microg/ml and all the CmaxGEN in excess of 9 microg/ml. The CIGEN was 13.8+/-3.8, with no individual value below 8. For the metronidazole, a dV of 0.68+/-0.2 l/kg was estimated and a Cl of 3.15+/-1.20 l/h and for the gentamicin, the dV as 0.23+/-0.06 l/kg and the Cl was 4.71+/-1.95 l/h. In patients undergoing CRS, surgical intervention did not significantly modify the pharmacokinetics of metronidazole or gentamicin in comparison with other groups of patients. The prophylaxis using a single, pre-surgical dose enables the achievement, for both antimicrobial agents, concentrations of a sufficient size to guarantee clinical efficacy. | 18,783,706 |
Regulated association of caveolins to lipid droplets during differentiation of 3T3-L1 adipocytes. | Caveolins, structural protein coats of caveolae primarily involved in membrane-related functions, have also been found associated to lipid droplets (LD), specialized organelles for fat storage. In the present study, we wanted to delineate the main features that govern the presence of caveolin-1 on adipocyte lipid droplets. Using either morphological or biochemical approaches, we found caveolins to associate to LD in 3T3-L1 adipocytes during their late maturation phase. The time course of this association could be modulated by constitutive activation of src-kinase, suggesting that the specific enrichment of caveolins in enlarged LD results from an active pathway rather than trapping of caveolins to lipid storage organelle acting as a passive sink. The fat cell size dependence of the association of organized caveolins on adipocytes LD suggests a role for these proteins in the long-term handling of lipid stores. | 18,783,721 |
Meprins, membrane-bound and secreted astacin metalloproteinases. | The astacins are a subfamily of the metzincin superfamily of metalloproteinases. The first to be characterized was the crayfish enzyme astacin. To date more than 200 members of this family have been identified in species ranging from bacteria to humans. Astacins are involved in developmental morphogenesis, matrix assembly, tissue differentiation and digestion. Family members include the procollagen C-proteinase (BMP1, bone morphogenetic protein 1), tolloid and mammalian tolloid-like, HMP (Hydra vulgaris metalloproteinase), sea urchin BP10 (blastula protein) and SPAN (Strongylocentrotus purpuratus astacin), the 'hatching' subfamily comprising alveolin, ovastacin, LCE, HCE ('low' and 'high' choriolytic enzymes), nephrosin (from carp head kidney), UVS.2 from frog, and the meprins. In the human and mouse genomes, there are six astacin family genes (two meprins, three BMP1/tolloid-like, one ovastacin), but in Caenorhabditis elegans there are 40. Meprins are the only astacin proteinases that function on the membrane and extracellularly by virtue of the fact that they can be membrane-bound or secreted. They are unique in their domain structure and covalent subunit dimerization, oligomerization propensities, and expression patterns. They are normally highly regulated at the transcriptional and post-translational levels, localize to specific membranes or extracellular spaces, and can hydrolyse biologically active peptides, cytokines, extracellular matrix (ECM) proteins and cell-surface proteins. The in vivo substrates of meprins are unknown, but the abundant expression of these proteinases in the epithelial cells of the intestine, kidney and skin provide clues to their functions. | 18,783,725 |
Evidence Locator: sources of evidence-based dentistry information. | Multiple resources are available to help practitioners access the latest scientific evidence. Evidence-based dentistry (EBD) is an approach to clinical decision making that incorporates the most current and comprehensive scientific evidence with the practitioner's judgment and the patient's needs and preferences. One challenge in implementing this approach is access to evidence, and there are multiple online resources that can be used in this endeavor. This article presents the Evidence Locator, a list of Web sites that provide access to "secondary sources" of evidence. Such "secondary sources" are typically summaries of systematic reviews and evidence-based clinical recommendations or guidelines. Also presented is a list of other Web sites that may be useful to the practitioner in implementing EBD. | 18,783,754 |
Psychometric properties and cross-cultural equivalence of the Arabic Social Capital Scale: instrument development study. | Social capital, defined as an investment in relationships that facilitates the exchange of resources, has been identified as a possible protective factor for child health in the context of risk factors such as poverty. Reliable and valid measures of social capital are needed for research and practice, particularly in non-English-speaking populations in developing countries. To evaluate the psychometric properties and cross-cultural equivalence of the Arabic translation of the Social Capital Scale (SCS). Descriptive, cross-sectional study for psychometric testing of a translated tool. Two metropolitan health clinics in Alexandria, Egypt. A convenience sample of 117 Egyptian parents of children with chronic conditions. To be eligible to participate, respondents had to be a parent of child with a chronic health condition between the ages of 1 and 18 years. The sample included primarily biological parents between the ages of 20 and 56 years. The 20-item Arabic SCS was administered as part of a written survey that included additional measures on demographic information and parent ratings of the child's overall health. Six items were ultimately removed based on item analysis, and exploratory factor analysis was conducted on the resulting 14-item scale. As a measure of construct validity, hypothesis testing was conducted using an independent samples t-test to determine whether a significant difference exists between mean total social capital scores for two groups of respondents based on the parental rating of the child's overall health. Item and factor analysis yielded preliminary support for a revised, 14-item Arabic SCS with four internally consistent factors. The standardized item alpha reliability coefficient for the total 14-item scale was .75. Respondents who reported that their child was in good health had significantly higher social capital scores than those who rated their child's health as poor. The 14-item Arabic SCS was found to be reliable and valid in this sample, with four internally consistent factors. While the tool may not be appropriate for comparing social capital between cultural groups, it will enable clinicians and researchers to address an important gap in knowledge characterized by a paucity of research on childhood chronic illness in low- and middle-income countries such as Egypt. | 18,783,773 |
Ultrafine porous carbon fibers for SO2 adsorption via electrospinning of polyacrylonitrile solution. | This work describes the potential capability of ultrafine porous carbon fibers (UPCF) prepared via electrospinning in the removal of SO2 from a mixture gas stream. A series of conventional PCF (CPCF) and ultrafine PCF (UPCF) were produced under the identical conditions and UPCF was also modified. Compared to the CPCF, experimental results showed that the UPCF had a better adsorption capacity for SO2 due to its higher surface area and microporous volume. After the modification of the UPCF, adsorption capacities of UPCF for SO2 were improved further via increasing the N-containing amount of UPCF and substrate which was followed by few changes in its specific surface area. The optimum concentration of modified reagent is 10%. From the results of the fatigue test, it has been found that both the UPCF and the modified UPCF showed a good durability. | 18,783,785 |
Prospective study of etiologic agents of acute gastroenteritis outbreaks in child care centers. | To investigate the etiology of outbreaks of acute gastroenteritis (AGE) in children attending childcare centers (CCCs) in North Carolina between October 2005 and March 2007. In this prospective study of outbreaks of AGE in CCCs, stool specimens from symptomatic children and environmental surface swabs were tested for adenovirus group F, astrovirus, norovirus (NoV), rotavirus group A, and sapovirus using real-time and conventional reverse transcription-polymerase chain reaction assays, and viruses were genotyped by sequencing. A total of 29 AGE outbreaks were evaluated, of which 13 (45%) were caused by a single virus, including rotavirus group A (17%), NoV (10%), astrovirus (10%), and sapovirus (7%). Multiple viruses were detected in 3 outbreaks (10%). Environmental swabs from 13 of 22 outbreaks (59%) tested positive for at least 1 virus and confirmed the findings of the same virus in the fecal specimens for 10 of the outbreaks (45%). This study confirms that viruses are major causes of AGE outbreak in CCCs. Our finding of widespread environmental contamination during such outbreaks suggests the need to study the effectiveness of current surface disinfectants against multiple gastroenteritis viruses in CCCs. | 18,783,794 |
The relationship of retinol binding protein 4 to changes in insulin resistance and cardiometabolic risk in overweight black adolescents. | To assess, among overweight non-hispanic black adolescents the relationship of changes in plasma retinol binding protein 4 (RBP4) over 3 years to changes in insulin resistance (IR) and 4 associated cardiometabolic risks. Nested, retrospective study of 51 overweight, post-pubertal non-Hispanic black participants in the Princeton School District Study. Participants were in the top (worsening IR) or bottom (improved IR) quartile for 3-year change in IR. RBP4 was measured by quantitative Western blot with frozen plasma. Regression analyses adjusted for age, sex, and adiposity (baseline and change). Three measures of adiposity were assessed (waist circumference, body mass index, and weight) in separate regression models. RBP4 increased in one third (n = 17). In logistic regression analyses, increased RBP4 was associated with significantly higher odds of worsening as opposed to improved IR independent of age, sex, or adiposity. Odds ratios were 5.6 (weight, P = .024), 6.0 (BMI, P = .025) and 7.4 (waist circumference, P = .015). Initial RBP4 (beta = 0.81, P = .005) and change in RBP4 (beta = 0.56, P = .046) also predicted change in triglycerides, but not change in high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, or fibrinogen. This retrospective cohort study provides evidence that RBP4 may be a mechanism through which obesity influences insulin resistance and hypertriglyceridemia in overweight postpubertal black youth and suggests utility of RBP4 as a biomarker of risk. | 18,783,798 |
Links between parenting and extra-familial relationships: nature or nurture? | The current paper examined associations between parenting and both peer group characteristics and friendship quality within a genetically sensitive design. Participants were aged 12-19 years (approximately equal numbers of males and females), including 424 sibling pairs and 1185 twin pairs, of whom 328 were MZ, 311 were DZ same-sex, 463 were DZ opposite-sex and 83 were of unknown zygosity. The adolescents provided self-report questionnaire measures of parental discipline, friendship quality, and peer group characteristics. All three relationship measures were moderately to substantially heritable. The novel and provocative finding, that adolescents' genetic propensities are largely responsible for the overlap seen between parental discipline strategies and friendship quality, is discussed in terms of its implications for socialization theory and understanding of adolescent relationships. | 18,783,821 |
PP2 regulates human trophoblast cells differentiation by activating p38 and ERK1/2 and inhibiting FAK activation. | Throughout gestation, fetal growth and development depend, in part, on placental transfer of nutrients from the maternal circulation. This latter function depends on multinucleated, terminally differentiated syncytiotrophoblasts. In vitro, freshly isolated cytotrophoblast cells differentiate spontaneously into syncytiotrophoblast in the presence of fetal bovine serum (FBS). We have previously showed that trophoblast differentiation is regulated by ERK1/2 and p38. Moreover, we showed that PP2 [4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3, 4-d]pyrimidine], a Src family kinase (SFK) specific inhibitor, stimulates biochemical trophoblast cells differentiation while it inhibits cell adhesion and spreading without affecting cell fusion. Therefore, we examined the mechanisms by which PP2 modulates trophoblast cells differentiation. This study shows that PP2 stimulates ERK1/2 and p38 activation after 24h of treatments and up to 3 days while it inhibits focal adhesion kinase (FAK) phosphorylation at many sites including Tyr-397, 407, 576 and 577. Furthermore, we showed that transient activation of ERK1/2 by FBS is independent of SFK and that PP2 induces rapid activation of p38. Moreover, the kinase activity of SFK is negatively regulated by the phosphorylation of their carboxy (C)-terminal regulatory tyrosines by specific proteins called carboxyl-terminal Src kinase (Csk) and Csk homologous kinase (CHK). We showed the expression of Csk and CHK in human trophoblast cells. In summary, this study showed that PP2 stimulates the biochemical differentiation of trophoblast cells by stimulating p38 and ERK1/2 while it inhibits the morphological differentiation by inhibiting FAK activation. | 18,783,823 |
Simulating calcium influx and free calcium concentrations in yeast. | Yeast can proliferate in environments containing very high Ca(2+) primarily due to the activity of vacuolar Ca(2+) transporters Pmc1 and Vcx1. Yeast mutants lacking these transporters fail to grow in high Ca(2+) environments, but growth can be restored by small increases in environmental Mg(2+). Low extracellular Mg(2+) appeared to competitively inhibit novel Ca(2+) influx pathways and to diminish the concentration of free Ca(2+) in the cytoplasm, as judged from the luminescence of the photoprotein aequorin. These Mg(2+)-sensitive Ca(2+) influx pathways persisted in yvc1 cch1 double mutants. Based on mathematical models of the aequorin luminescence traces, we propose the existence in yeast of at least two Ca(2+) transporters that undergo rapid feedback inhibition in response to elevated cytosolic free Ca(2+) concentration. Finally, we show that Vcx1 helps return cytosolic Ca(2+) toward resting levels after shock with high extracellular Ca(2+) much more effectively than Pmc1 and that calcineurin, a protein phosphatase regulator of Vcx1 and Pmc1, had no detectable effects on these factors within the first few minutes of its activation. Therefore, computational modeling of Ca(2+) transport and signaling in yeast can provide important insights into the dynamics of this complex system. | 18,783,827 |
Metal levels in the bones and livers of globally threatened marbled teal and white-headed duck from El Hondo, Spain. | El Hondo is a key area for marbled teal and white-headed duck. We present Pb, Cu, Zn, Se, and As data for bone and liver in birds found dead between 1996 and 2001. Several metals were higher in adult white-headed ducks than in marbled teal. They were higher in female than in male white-headed ducks, and did not differ with sex in marbled teal, but did by age. Lead in liver of adults was influenced by Pb shot ingestion, which was detected in 21% of marbled teal and in 71% of white-headed duck. No marbled teal had liver levels indicative of Pb poisoning, while 86% of white-headed ducks did. Selenium, Zn, and Cu were elevated in 13%, 7%, and 39% of birds, respectively. Whilst Pb shot poses the greatest threat to these species, further work should assess exposure via plants, invertebrates, water, and sediments for other metals, and investigate possible sub-lethal effects. | 18,783,829 |
Increased plasma levels of 8-iso-PGF2alpha and IL-6 in an elderly population with depression. | Oxidative damage and immune-inflammatory activation have been suggested to play a role in depression. The purpose of the study was to investigate possible associations and interactions of these pathophysiological mechanisms in geriatric depression by determining the levels of plasma 8-iso-prostaglandin F(2alpha) (8-iso-PGF(2alpha)) and interleukin-6 (IL-6) in elderly depressed individuals. Subjects over 60 years of age with depression and controls were randomly selected from a population in the community after screening with the Geriatric Depression Scale. Plasma concentrations of 8-iso-PGF2alpha and IL-6 were measured in both groups. Depressed patients had significantly higher mean (+/-S.D.) 8-iso-PGF2alpha levels compared to healthy controls (245.01+/-179.92 pg/ml vs 97.64+/-42.72 pg/ml, respectively). Similarly, the same groups demonstrated significantly elevated IL-6 levels compared with controls (58.73+/-39.90 pg/ml vs 15.41+/-9.27 pg/ml). This study indicates an association between increased levels of plasma 8-iso-PGF2alpha and IL-6 with depressive symptomatology in elderly individuals and indicates the necessity for further investigation, possibly within the framework of an integrated involvement of oxidative damage and inflammation in the pathophysiology of depression in the elderly. | 18,783,834 |
Priority setting for technology adoption at a hospital level: relevant issues from the literature. | The increasing pace of development of healthcare technologies obliges hospitals to increase both the rationality and the accountability of priority setting for technology adoption. This paper aims at identifying which are the relevant issues for technology assessment and selection at a hospital level and at grouping them in a reference framework. An electronic search from January 1990 onwards, covering PubMed, Medline and CILEA, has been carried out in order to collect the relevant contributions. A total of 20 studies were selected from the fields of health policy, management of technology and biomedical engineering. Two main assessment perspectives have been identified and detailed: value generation at a hospital level and level of sustainability in the implementation stage. Four types of investment in technology at a hospital level have been identified combining the perspectives. Moreover, the two perspectives have been deployed in a list of 19 relevant issues that should be reviewed during the budget process. The proposed framework can aid priority setting for technology adoption at a hospital level and contribute to increase both the rationality and the accountability of technology assessment and selection in the budget process. | 18,783,844 |
Conflict in schools: student nurses' conflict management styles. | Unless conflicts between the students and the instructors can be successfully managed, they will certainly result in negative outcomes for the students. The conflict management styles of the students should be recognized in detail in order to attain positive outcomes in regard to the conflict management styles. The purpose of this study was to examine the conflict management styles used by nursing students in conflict with faculty members and the differences in use of style from the aspect of some variables. This study was conducted with 151 students in a public university nursing school. Data were collected using a personal information form and the Rahim Organizational Conflict Inventory II (ROCI II). The data were analyzed using descriptive statistics, ANOVA, Tukey test, Kruskal Wallis test, Mann-Whitney U test and Cronbach alpha coefficient analyses. The students were found to use integrating (X=3.82) and obliging (X=3.81) styles the most, and dominating style (X=3.02) the least. In addition there were differences determined in management style between classes, frequency of experiencing conflict, and feeling of success in the conflict (p<0.05). It was determined that the integrating and obliging styles were used more by those who evaluated themselves as successful in conflict management, but the avoiding and compromising styles were used more by students who evaluated themselves as unsuccessful. It was determined that the students preferred to use styles that produced positive results in conflict resolution and that the frequency of experiencing conflict and the feeling of success in conflict had an effect on choice of style. It will be helpful to analyze the relationship between the causes of conflict between the student and the instructor in the practice field and the uses of conflict management styles. | 18,783,853 |
Examination of the association between male gender and preterm delivery. | To examine possible reasons why a male fetus constitutes a risk factor for preterm delivery. Retrospective study of deliveries from hospital database in a UK teaching hospital. The population comprised all deliveries >23 weeks over an 11-year period, excluding multiples, terminations and pregnancies with major abnormalities including indeterminate gender. Obstetric variables and outcomes were initially compared in male and female babies for preterm births in different gestation bands, extreme (<28 weeks), severe (29-32 weeks) and moderate (33-36 weeks). For each, the odds ratios with 95% confidence intervals for preterm delivery were calculated. Then, using binary logistic regression with adjusted odds ratios with 95% confidence intervals, putative causal pathways that might explain the male excess were tested. 75,725 deliveries occurred, of which 4003 (5.3%) were preterm. Males delivered preterm more frequently (OR 1.13, 95% CI 1.06-1.20). This was due to spontaneous (OR 1.30, 95% CI 1.19-1.42) but not iatrogenic (OR 0.96, 95% CI 0.87-1.05) preterm birth. There was an increased risk of pre eclampsia among preterm females. Although males were larger, and male pregnancies were more frequently nulliparous and affected by some other obstetric complications (abruption, urinary tract infection), these did not account for their increased risk. Any effect of growth restriction could not be properly determined. Being male carries an increased risk of spontaneous but not iatrogenic preterm birth. The reasons behind this remain obscure. | 18,783,867 |
The relationship between erectile dysfunction and lower urinary tract symptoms and the role of phosphodiesterase type 5 inhibitors. | The relationship between lower urinary tract symptoms (LUTS) and erectile dysfunction (ED) and the potential interplay of phosphodiesterase type 5 inhibitors (PDE5-I) have clinical implications for both patient screening and treatment. To describe the current literature assessing the LUTS-ED relationship and the role of PDE5-I from both a basic science and clinical intervention perspective. We focused on data recently published (1990-2008) describing epidemiologic and mechanistic manuscripts of the LUTS-ED relationship with emphasis on papers involving PDE5-I-particularly those using level 1 evidence clinical trials. Base key words used included BPH, LUTS, ED, and phosphodiesterase inhibitors in combination with such secondary key words as nitric oxide, autonomic hyperactivity, Rho-kinase, atherosclerosis, and mechanism. We abstracted >200 articles and reviewed >100. The large overlap of elderly men with both LUTS and ED likely stems from a cause-and-effect relationship. Thus far, four proposed mechanisms attempt to explain the relationship between LUTS and ED. Multiple studies showing that PDE5-I improved LUTS have been performed. Understanding the role of PDE5-I in the LUTS and ED relationship affects patient screening and treatment but also raises further research questions. The future use of phosphodiesterase inhibitors as either prophylaxis or as a primary treatment for LUTS looms as a possibility and may not be limited to men. | 18,783,872 |
Time, symptom burden, androgen deprivation, and self-assessed quality of life after radical prostatectomy or watchful waiting: the Randomized Scandinavian Prostate Cancer Group Study Number 4 (SPCG-4) clinical trial. | Quality-of-life outcomes are important in the choice of treatment strategy for men with localized prostate cancer. To evaluate how follow-up time, number of physical symptoms, and presence of androgen deprivation affected quality of life among men randomized to radical prostatectomy or watchful waiting. The study group was composed of all 376 living men included in the Swedish part of the Scandinavian Prostate Cancer Group Study Number 4 (SPCG-4) between January 1, 1989, and February 29, 1996. Quality-of-life data were collected after a mean follow-up time of 4.1 yr. All patients were randomly assigned to radical prostatectomy or watchful waiting. Forty-five men were androgen deprived. Data of specific symptoms, symptom-induced stress, sense of well-being, and self-assessed quality of life were obtained by means of a questionnaire. Psychological symptoms were assessed using seven-point visual digital scales. In analyses stratified on the basis of the numbers of physical symptoms, anxiety and depressed mood were less common, and sense of well-being and self-assessed quality of life were better throughout in the radical prostatectomy group than in the watchful waiting group. As the number of physical symptoms increased, all psychological variables became worse and more prominent in the watchful waiting group. After a follow-up time of 6-8 yr, a significant decrease in quality of life (p=0.03) was seen in the watchful waiting group. Twenty-four percent of androgen-deprived patients assigned to watchful waiting reported high self-assessed quality of life compared with 60% in the radical prostatectomy group. Eighty-eight percent of patients had clinically detected tumors. Androgen deprivation negatively affected self-assessed quality of life in men assigned to watchful waiting. The number of physical symptoms was associated with the level of quality of life. Quality of life was lower with longer follow-up time in both groups and was statistically significant in the watchful waiting group (p=0.03). | 18,783,877 |
Test of memory malingering and word memory test: a new comparison of failure concordance rates. | Two commonly used symptom validity tests are the Test of Memory Malingering (TOMM) and Word Memory Test (WMT). After examining TOMM-WMT failure concordance rates, Green [Green, P. (2007). Making comparisons between forced-choice effort tests. In K. B. Boone (Ed.), Assessment of feigned cognitive impairment (pp. 50-77). New York: Guilford] urged widespread adoption of the WMT, arguing the TOMM is insensitive to feigned impairment. But Green (2007) used a skewed concordance method that favored WMT (one TOMM subtest vs. three WMT subtests). In the present study we compare pass/fail agreement rates with different combinations of TOMM and WMT subtests in 473 persons seeking compensation for predominately mild neurological trauma. We replicated Green (2007) using his asymmetrical method, but otherwise we found the WMT and TOMM produce comparable failure rates in samples at-risk for exaggeration with balanced comparison (three TOMM subtests vs. three WMT). Further work is necessary to compare WMT and TOMM specificities, as failure concordance designs establish reliability but are insufficient for proving validity. | 18,783,912 |
Adhesive efficiency of spider prey capture threads. | Cribellar capture threads are comprised of thousands of fine silk fibrils that are produced by the spigots of a spider's cribellum spinning plate and are supported by larger interior axial fibers. This study examined factors that constrain the stickiness of cribellar threads spun by members of the orb-weaving family Uloboridae in the Deinopoidea clade and compared the material efficiency of these threads with that of viscous capture threads produced by members of their sister clade, the Araneoidea. An independent contrast analysis confirmed the direct relationship between cribellar spigot number and cribellar thread stickiness. A model based on this relationship showed that cribellar thread stickiness is achieved at a rapidly decreasing material efficiency, as measured in terms of stickiness per spigot. Another limitation of cribellar thread was documented when the threads of two uloborid species were measured with contact plates of four widths. Unlike that of viscous threads, the stickiness of cribellar threads did not increase as plate width increased, indicating that only narrow bands along the edges of thread contact contributed to their stickiness. As thread volume increased, the gross material efficiency of cribellar threads decreased much more rapidly than that of viscous threads. However, cribellar threads achieved their stickiness at a much greater gross material efficiency than did viscous threads, making it more challenging to explain the transition from deinopoid to araneoid orb-webs. | 18,783,928 |
Isolation of the orthologue of the cerato-ulmin gene in Ophiostoma quercus and characterization of the purified protein. | Ophiostoma quercus is an ophiostomatoid fungus strictly related to the Ophiostoma's (O. ulmi, O. novo-ulmi, and O. himal-ulmi) that cause Dutch elm disease (DED). O. quercus has a number of morphological characteristics in common with the DED pathogens, and is a well-known and economically important sapstaining fungus occurring worldwide on hardwoods and commercially produced pines, and causes typical cankers on oak stems. In elm trees O. quercus can survive for months without causing any disease symptoms. DED fungi produce cerato-ulmin (CU), a class II hydrophobin, which is generally considered as the main toxin potentially involved in various phases of the DED pathogenesis. In the present work we isolated and sequenced the orthologue of the cu gene in the O. quercus isolates H988, H1042, and H2053. Moreover the CU protein from O. quercus isolate H988 was also purified and characterized. Sequence analysis showed that there is a pronounced difference between the whole cu gene region of O. quercus and the homologous fragments of the DED-causing species O. ulmi, O. novo-ulmi, and O. himal-ulmi. It also appeared that differences in the structural conformation of the promoter were unlikely to play a role in the modulation of the transcript level and that, for O. quercus, differences in CU production did not result from the potential different regulation levels. Clear differences were shown in the transcriptional unit of the cu genes and in the amino acid sequences among all the CUs. The purified O. quercus CU was separated using matrix-assisted laser desorption ionization/time of flight (MALDI-TOF) spectrometry into seven forms of increasing molecular weight from 7190 to 7724Da. The hydrophobicity profiles indicated that two regions of the O. quercus CU protein were more hydrophobic than the corresponding regions of the CUs of the DED fungi. The O. quercus CUs had theoretical isoelectric point values similar to those of the DED fungi. Finally, the contradiction between the consistent differences between these four Ophiostoma species in the cu gene region and in the CU proteins and their strict phylogenetic relationship is discussed. | 18,783,930 |
Hormone replacement therapy and the risk of breast cancer. | Hormone replacement therapy (HRT) has had a chequered history ever since its initial use to manage menopausal symptoms. It is clear that it has many other effects and here we review its impact on the risk of breast cancer. A clear risk is seen for current uses of combined oestrogen/progestagen pills, but this returns to normal shortly after treatment cessation. The role of oestrogen only replacement therapy is less clear, but most studies find a weaker, but still positive, association in current users. Recent sharp reductions in HRT use have been correlated with declines in breast cancer incidence in the USA, but not so clearly elsewhere. | 18,783,940 |
Structure-activity relationships of compounds targeting mycobacterium tuberculosis 1-deoxy-D-xylulose 5-phosphate synthase. | We report on a target-based approach to identify possible Mycobacterium tuberculosis DXS inhibitors from the structure of a known transketolase inhibitor. A small focused library of analogs was assembled in order to begin elucidating some meaningful structure-activity relationships of 3-(4-chloro-phenyl)-5-benzyl-4H-pyrazolo[1,5-a]pyrimidin-7-one. Ultimately we found that 2-methyl-3-(4-fluorophenyl)-5-(4-methoxy-phenyl)-4H-pyrazolo[1,5-a]pyrimidin-7-one, although still weak, was able to inhibit M. tuberculosis DXS with an IC(50) of 10.6 microM. | 18,783,951 |
Trapping of intact, singly-charged, bovine serum albumin ions injected from the atmosphere with a 10-cm diameter, frequency-adjusted linear quadrupole ion trap. | High-resolution real-time particle mass measurements have not been achievable because the enormous amount of kinetic energy imparted to the particles upon expansion into vacuum competes with and overwhelms the forces applied to the charged particles within the mass spectrometer. It is possible to reduce the kinetic energy of a collimated particulate ion beam through collisions with a buffer gas while radially constraining their motion using a quadrupole guide or trap over a limited mass range. Controlling the pressure drop of the final expansion into a quadrupole trap permits a much broader mass range at the cost of sacrificing collimation. To achieve high-resolution mass analysis of massive particulate ions, an efficient trap with a large tolerance for radial divergence of the injected ions was developed that permits trapping a large range of ions for on-demand injection into an awaiting mass analyzer. The design specifications required that frequency of the trapping potential be adjustable to cover a large mass range and the trap radius be increased to increase the tolerance to divergent ion injection. The large-radius linear quadrupole ion trap was demonstrated by trapping singly-charged bovine serum albumin ions for on-demand injection into a mass analyzer. Additionally, this work demonstrates the ability to measure an electrophoretic mobility cross section (or ion mobility) of singly-charged intact proteins in the low-pressure regime. This work represents a large step toward the goal of high-resolution analysis of intact proteins, RNA, DNA, and viruses. | 18,783,963 |
Synthesis, characterization and antioxidant activity copper-quercetin complex. | Quercetin (3,3',4',5,7-pentahydroxyflavone) one of the most abundant dietary flavonoids, has been investigated in the presence of Cu(II) in methanol. The spectroscopic studies (UV-vis, (1)H NMR and IR) were useful to assess the relevant interaction of Quercetin with Cu(II) ions, the chelation sites and dependence of the complex structure from the metal/ligand ratio. A 1:2 (L:M) complex was indicated by Job's method of continuous variation, which was applied to ascertain the stoichiometric composition of the complex. The antioxidant activities of the compounds were evaluated by using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. The complexed flavonoid was much more effective free radical scavengers than the free flavonoids. | 18,783,981 |
The childhood obesity pandemic: Promoting knowledge for undergraduate nursing students. | The rise in childhood obesity is acknowledged as a major health problem in many countries. Health issues directly related to the childhood obesity pandemic are numerous as are the risk factors in its development. No single strategy is likely to be effective in reversing this alarming trend, rather, nurses need to work with children and families by providing education, guidance, and support to promote a change in the many lifestyle factors that have helped to create this health problem. Curriculum, teaching practices and assignment topics based on contemporary health issues of relevance to nursing practice support the importance of educating nursing students on this worrying health issue. The use of a creative strategy to help students learn about the childhood obesity problem can also be utilised to encourage lateral thinking in students. Thus, an assignment can have two significant goals in the development of knowledge and understanding of childhood obesity but also personal discovery of creative ability to design a method that engages children in learning about this health problem and what they can do to avoid its development. | 18,783,989 |
Use of p16-INK4A overexpression to increase the specificity of human papillomavirus testing: a nested substudy of the NTCC randomised controlled trial. | Human-papillomavirus (HPV) testing is more sensitive, but less specific, than conventional cytology for detecting high-grade cervical intraepithelial neoplasia (CIN). We assessed whether HPV testing with triage by p16-INK4A overexpression can increase specificity while maintaining sensitivity. HPV-positive women were enrolled between June 10, 2003, and Dec 31, 2004 in a multicentre randomised controlled trial, which compared stand-alone HPV testing by Hybrid Capture 2 (experimental group) with conventional cytology, were referred for colposcopy. In seven of nine centres, cytospin preparations from these women were tested for p16-INK4A overexpression by immunostaining. The sensitivity and specificity for CIN grade 2 or more, determined at blind review of histology, were calculated for these women. We also estimated the relative sensitivity and relative referral to colposcopy that would have been obtained by HPV testing with p16-INK4A triage compared with conventional cytology. This trial is registered as a Standard Randomised Controlled Trial, number ISRCTN81678807. 24 661 women were randomly assigned to the experimental group. 1137 women (74% of those undergoing colposcopy in relevant centres), including 50 with CIN2 and 42 with CIN3 or cancer, had valid p16-INK4A immunostaining. For the endpoint of CIN2+, sensitivity and specificity of p16-INK4A (deemed positive with any number of stained cells-except endocervical, metaplastic, and atrophic cells if morphologically normal) in HPV-positive women of any age were 88% (81 of 92; 95% CI 80-94) and 61% (633 of 1045; 57-64), respectively. In the 35-60-year age group, the relative sensitivity of HPV testing and p16-INK4A triage versus conventional cytology for CIN2+ was 1.53 (95% CI 1.15-2.02) and relative referral was 1.08 (0.96-1.21). In the 25-34-year age group, relative sensitivity was 3.01 (1.82-5.17) and relative referral was 1.15 (0.96-1.37). In the latter age group, when 5% or more stained cells were deemed positive, the corresponding values were 2.06 (1.20-3.68) and 0.58 (0.46-0.73), respectively. HPV testing with p16-INK4A triage produces a significant increase in sensitivity compared with conventional cytology, with no substantial increase in referral to colposcopy. | 18,783,988 |
Accelerating risk of Fidelis lead fracture. | Sprint Fidelis (Medtronic Inc., Minneapolis, Minnesota) is a 6.6-F implantable cardioverter-defibrillator lead. In October 2007 the manufacturer suspended distribution of Sprint Fidelis leads secondary to high early fracture rates. Reprogramming of lead impedance alerts was recommended to try to reduce inappropriate shocks. This study sought to assess how the hazard of Fidelis fracture varies with time, whether lead impedance alert thresholds programmed after recall have prevented inappropriate shocks, and predictors of lead fracture. We collected clinical and device interrogation data on all lead fractures and performed a Kaplan-Meier analysis. We performed a case control study to examine univariate and multivariate predictors of lead fracture. There have been 17 lead fractures in our cohort of 480 Sprint Fidelis (model 6949) leads, median follow-up 19.8 months. The hazard of fracture increased significantly with time by a power of 2.74 (95% confidence interval: 2.57 to 2.91, P <.0001). Reprogrammed lead impedance thresholds prevented inappropriate shocks in only 1 of 6 patients. Independent predictors of lead fracture were greater left ventricular ejection fraction (P = .0011) and noncephalic venous access (P = .0224). The risk of lead fracture increased with time by a power of 2.74. Reprogrammed lead impedance thresholds prevented inappropriate shocks in only 1 of 6 patients. Independent predictors of lead fracture were greater left ventricular ejection fraction and noncephalic access. | 18,783,996 |
Practical Poissonian-Gaussian noise modeling and fitting for single-image raw-data. | We present a simple and usable noise model for the raw-data of digital imaging sensors. This signal-dependent noise model, which gives the pointwise standard-deviation of the noise as a function of the expectation of the pixel raw-data output, is composed of a Poissonian part, modeling the photon sensing, and Gaussian part, for the remaining stationary disturbances in the output data. We further explicitly take into account the clipping of the data (over- and under-exposure), faithfully reproducing the nonlinear response of the sensor. We propose an algorithm for the fully automatic estimation of the model parameters given a single noisy image. Experiments with synthetic images and with real raw-data from various sensors prove the practical applicability of the method and the accuracy of the proposed model. | 18,784,024 |
The role of surveillance and data use in the development of public health policies. | Decision makers consider numerous factors besides surveillance data in establishing public health policies and programmes. In an evidence-informed system, it is important to collect, interpret, and present information that has maximum impact on the broader policy agenda.Successful policies and programmes are rational, feasible, and practical, with wide public support. Surveillance systems must align and interact with the other parts of the policy infrastructure. There must be continuous links between data providers, collectors, and users. Data must be representative of population variations.For chronic diseases, the major challenge is multiple risks. Surveillance systems must capture many factors from many sources. Data must be presented in plain language and tailored to the needs of various users - politicians, policy makers, health providers, researchers, and the public. Data must be linked to other policy areas such as taxation. Economic arguments, including modelling, strongly influence decisions. Broad data ownership through alliances also has significant impact. | 18,784,050 |
Hunting happiness or promoting health? Why positive psychology deserves a place in health promotion. | This commentary asks the question of whether positive psychology represents an egoistic pursuit of happiness, which is in conflict with basic values within health promotion. A look at key concepts and research findings within positive psychology reveals common ground with health promotion. Similarities are evident in conceptualization of health, resource focus, value focus and consequences for policy. Some influences of happiness on health and functioning are described. | 18,784,052 |
The structural basis for T-antigen hydrolysis by Streptococcus pneumoniae: a target for structure-based vaccine design. | Streptococcus pneumoniae endo-alpha-N-acetylgalactosaminidase is a cell surface-anchored glycoside hydrolase from family GH101 involved in the breakdown of mucin type O-linked glycans. The 189-kDa mature enzyme specifically hydrolyzes the T-antigen disaccharide from extracellular host glycoproteins and is representative of a broadly important class of virulence factors that have remained structurally uncharacterized due to their large size and highly modular nature. Here we report a 2.9 angstroms resolution crystal structure that remarkably captures the multidomain architecture and characterizes a catalytic center unexpectedly resembling that of alpha-amylases. Our analysis presents a complete model of glycoprotein recognition and provides a basis for the structure-based design of novel Streptococcus vaccines and therapeutics. | 18,784,084 |
10-year follow-up of intensive glucose control in type 2 diabetes. | During the United Kingdom Prospective Diabetes Study (UKPDS), patients with type 2 diabetes mellitus who received intensive glucose therapy had a lower risk of microvascular complications than did those receiving conventional dietary therapy. We conducted post-trial monitoring to determine whether this improved glucose control persisted and whether such therapy had a long-term effect on macrovascular outcomes. Of 5102 patients with newly diagnosed type 2 diabetes, 4209 were randomly assigned to receive either conventional therapy (dietary restriction) or intensive therapy (either sulfonylurea or insulin or, in overweight patients, metformin) for glucose control. In post-trial monitoring, 3277 patients were asked to attend annual UKPDS clinics for 5 years, but no attempts were made to maintain their previously assigned therapies. Annual questionnaires were used to follow patients who were unable to attend the clinics, and all patients in years 6 to 10 were assessed through questionnaires. We examined seven prespecified aggregate clinical outcomes from the UKPDS on an intention-to-treat basis, according to previous randomization categories. Between-group differences in glycated hemoglobin levels were lost after the first year. In the sulfonylurea-insulin group, relative reductions in risk persisted at 10 years for any diabetes-related end point (9%, P=0.04) and microvascular disease (24%, P=0.001), and risk reductions for myocardial infarction (15%, P=0.01) and death from any cause (13%, P=0.007) emerged over time, as more events occurred. In the metformin group, significant risk reductions persisted for any diabetes-related end point (21%, P=0.01), myocardial infarction (33%, P=0.005), and death from any cause (27%, P=0.002). Despite an early loss of glycemic differences, a continued reduction in microvascular risk and emergent risk reductions for myocardial infarction and death from any cause were observed during 10 years of post-trial follow-up. A continued benefit after metformin therapy was evident among overweight patients. (UKPDS 80; Current Controlled Trials number, ISRCTN75451837.) | 18,784,090 |
Early results for below-knee bypasses using Distaflo. | In patients who require lower extremity revascularization, prosthetic graft is a reasonable alternative in the absence of a suitable autologous vein conduit. However, prosthetic bypass grafts have limited patency, especially for infrageniculate reconstruction. Polytetrafluoroethylene grafts were geometrically modified at the distal end to increase their patency. The authors reviewed their experience with the Distaflo graft in patients who required lower extremity below-knee popliteal and tibial bypasses when no suitable autologous vein conduit was available. Chart review was conducted of the 57 patients who underwent 60 lower extremity bypasses over a 3-year period between June 2003 and April 2006. Twenty-four revascularizations were constructed to the tibial outflow sites, whereas the remaining grafts were placed to the below-knee (28) and above-knee (8) popliteal artery, respectively. Study endpoints were primary, assisted primary, secondary patency, and limb salvage at the time of follow-up. Distaflo bypass was performed at the infrageniculate level in 86.7% of cases (28 below-knee popliteal, 24 tibial). Mean follow-up time was 12 months (range, 0.5-37.5 months). At 1 year, primary, assisted primary, and secondary patencies and limb salvage rates for below-knee popliteal bypasses were 83.5%, 89.5%, 94.7%, and 94.4%, respectively. Primary, assisted primary, and secondary patencies and limb salvage rates for tibial bypasses were 44.4%, 44.4%, 63.2%, and 74.9%, respectively. Distaflo precuffed graft is a good alternative conduit for below-knee popliteal and tibial lower extremity reconstructions in the absence of an autologous vein and appears to have promising early patency and limb salvage rates even when used for tibial bypasses. | 18,784,116 |
Sympathetic and sensory nerve activation during negative pressure therapy of sternotomy wounds. | Negative pressure wound therapy (NPWT) has been adopted as the first-line treatment for poststernotomy mediastinitis as a result of the excellent clinical outcome. The knowledge concerning the effects of NPWT on the cardiovascular system and homeostasis is still limited. The aim of the present study was to investigate whether the plasma levels of neurohormones change during NPWT. Six pigs underwent median sternotomy followed by NPWT at -125 mmHg. The plasma levels of noradrenaline, adrenaline, neuropeptide Y, substance P, vasoactive intestinal peptide (VIP), and calcitonin gene-related peptide (CGRP) were determined before (0 min) and 5, 20, 60 and 180 min after the application of NPWT. The results show a transient increase in the plasma levels of noradrenaline and adrenaline when NPWT was applied. The plasma level of the adrenergic co-transmitter neuropeptide Y was higher in NPWT--than in sham-treated pigs, after 180 min of negative pressure. After 180 min of NPWT there was an increase in the plasma levels of the sensory nerve transmitter substance P, while no such effect was observed for CGRP or VIP. In conclusion, the results suggest sympathetic nerve activation during NPWT. This may be the result of an increase in workload on the heart during the initial phase of NPWT. | 18,784,122 |
Endothelin--role in vascular disease. | It is now two decades since it was demonstrated that ET-1 is one of the most powerful vasoconstrictors in biology. ET-1 mediates its effects through two membrane G-protein coupled receptors, ET(A) and ET(B), which exhibit a wide tissue distribution including the endothelial cells, vascular smooth muscle cells and adventitial fibroblasts. In recent years, ET-1 has been identified as a key player of endothelial dysfunction in various cardiovascular, autoimmune and CTDs. Endothelial dysfunction results from endothelial cell injury subsequently leading to the generation of an inflammatory process and endothelial cell activation. Thus, beyond its known 'classical' vasoactive effects, ET-1 is additionally considered to be an important mediator in vessel remodelling ultimately leading to major changes in cellular and tissue architecture; it also appears to function in conjunction with other growth factors and cytokines. Consequently, ET-1 receptor antagonists may be useful in ameliorating progression of vascular dysfunction and vascular disease due to their ability to negatively modulate vasoconstrictor pathways, cytokines and inflammatory markers production, and growth factor effects. This review briefly summarizes the current knowledge on the role of ETs in vascular dysfunction and vascular disease, with a particular emphasis on ET-1 in CTDs. | 18,784,133 |
Endothelin and scleroderma lung disease. | Scleroderma-associated interstitial lung disease (SSc-ILD) occurs frequently and for many patients SSc-ILD is a significant complication of their disease. SSc-ILD is now one of the leading causes of death among patients with SSc. SSc-ILD, classified most often as a non-specific interstitial pneumonia, may culminate in interstitial pulmonary fibrosis and end-stage lung disease. Fibrosis in the lung is the net result of fibroblast proliferation and deposition of excessive amounts of extracellular matrix proteins. Among the many cytokines and growth factors involved in the pathogenesis of SSc-ILD, ET-1 may be a central mediator. In vitro and in vivo studies of animals and SSc patients support the notion that ET-1 can enhance the proliferation of pulmonary mesenchymal cells and may also enhance the fibrogenic effects of TGF-beta. Two well-designed randomized controlled trials of the dual ET receptor blocker bosentan were negative in their primary (and for SSc also secondary) endpoints, although there might be explanations for this apparent lack of efficacy. | 18,784,134 |
Adjustment of genomic waves in signal intensities from whole-genome SNP genotyping platforms. | Whole-genome microarrays with large-insert clones designed to determine DNA copy number often show variation in hybridization intensity that is related to the genomic position of the clones. We found these 'genomic waves' to be present in Illumina and Affymetrix SNP genotyping arrays, confirming that they are not platform-specific. The causes of genomic waves are not well-understood, and they may prevent accurate inference of copy number variations (CNVs). By measuring DNA concentration for 1444 samples and by genotyping the same sample multiple times with varying DNA quantity, we demonstrated that DNA quantity correlates with the magnitude of waves. We further showed that wavy signal patterns correlate best with GC content, among multiple genomic features considered. To measure the magnitude of waves, we proposed a GC-wave factor (GCWF) measure, which is a reliable predictor of DNA quantity (correlation coefficient = 0.994 based on samples with serial dilution). Finally, we developed a computational approach by fitting regression models with GC content included as a predictor variable, and we show that this approach improves the accuracy of CNV detection. With the wide application of whole-genome SNP genotyping techniques, our wave adjustment method will be important for taking full advantage of genotyped samples for CNV analysis. | 18,784,189 |
Study on the oxidative stress status among cement plant workers. | The cement industry is considered as a major pollution problem because of dust and particulate matter emitted at various steps of cement production. In the present study, volunteer male workers from a cement factory were studied for oxidative and nitrosative stress biomarkers in relation to their serum levels of aluminum (Al) and chromium (Cr). The subjects were divided into two groups of direct and indirect exposure. Subject who worked in production steps were considered as direct exposure group, and those who worked in administration building were considered as indirect exposure group. For comparison, healthy subjects at the same age and socioeconomic status were tested as a control group. Serum levels of lipid peroxidation (LP), total antioxidant capacity (TAC), total thiol molecules (TTM), and nitric oxide (NO) as well as Al and Cr were measured. The results indicated a significant increase in Al (P = 0.001) and Cr (P = 0.009) levels in direct-exposed workers in comparison to healthy control group. Further, a significant increase in Al (P = 0.002) and Cr (P = 0.009) levels was observed in direct-exposed workers as compared to indirect-exposed one. Serum levels of TTM and TAC were significantly lower in both direct- and indirect-exposed groups in comparison to healthy control group (P = 0.00). Serum TTM and TAC were significantly lower in direct-exposed workers as compared to indirect-exposed ones (P = 0.00 and P = 0.024, respectively). There was no significant difference on the level of LP and NO among groups. A correlation was found between serum level of Cr, TAC, and platelets between direct- and indirect-exposed groups (P < 0.05). Further correlation was found among serum level of Cr and those of TTM, platelets, and chronic disease (P < 0.05). Chronic disease had a significant influence adjusted to other predictor variables on the post-shift values of Al (P < 0.05). Although plasma levels of Al and Cr were found in normal ranges, analyses confirm their role in impairment of TMM and TAC. | 18,784,198 |
Occupational ototoxicity of n-hexane. | The ability of chemicals to produce hearing loss themselves or to promote noise-induced hearing loss has been reported for some organic solvents. The objective of this study was to review the literature on the effects of low-level exposure to n-hexane on the auditory system and consider its relevance for occupational settings. Both human and animal investigations were evaluated only for realistic exposure concentrations based on the permissible inhalation exposure limits. In Quebec, the time-weighted average exposure value (TWAEV) for 8 h is 50 ppm. In humans, the upper limit for considering ototoxicity data relevant to the occupational exposure situation was set at five times the TWAEV. Animal data were evaluated only for exposure concentrations up to 100 times the TWAEV. There is no convincing evidence of n-hexane-induced hearing loss in workers. In rats, n-hexane seems to affect auditory function; however, the site of these alterations cannot be determined from the present data. Further studies with sufficient data on the exposure of workers to n-hexane are necessary to make a definitive conclusion. In the interim, we recommend considering n-hexane as a possibly ototoxic agent. | 18,784,199 |
Whole-body CT trauma imaging with adapted and optimized CT angiography of the craniocervical vessels: do we need an extra screening examination? | Blunt carotid and vertebral artery injury (BCVI) is rare but potentially devastating. The objective of our study was to prospectively evaluate the usefulness of a dedicated and optimized CT angiography (CTA) protocol of the craniocervical vessels as part of a whole-body CT work-up of patients with multiple trauma in a population of patients with blunt trauma. From February 2006 to July 2007, a total of 368 consecutive patients with trauma were evaluated. All examinations were performed on a 16-row multisection CT (MSCT) scanner. CTA was performed from the level of the T2 vertebra to the roof of the lateral ventricles with 40 mL of iodinated contrast agent. Images were reconstructed with use of the angiography and bone window settings to evaluate vessels and bones. Of all eligible patients imaged, 100 had injuries to the head and neck including 35 skull base fractures (9.5%), 24 maxillofacial (6.5%), and 11 cervical spine fractures (3%). CTA was diagnostic in all patients. BCVI was diagnosed in 6 cases (6 lesions of the internal carotid artery, 3 lesions of the vertebral artery); among them were 2 who did not meet the screening criteria. No patient with negative results on CTA subsequently had development of neurologic deficits suspicious for BCVI. This study confirms that optimized craniocervical CTA can be easily integrated into a whole-body CT protocol for patients with multiple trauma. No additional screening technique is necessary to identify clinically relevant vascular injuries. Earlier recognition enables earlier treatment and may decrease mortality and morbidity rates of these rare but potentially devastating injuries. | 18,784,210 |
Schistosomiasis and infection with human immunodeficiency virus 1 in rural Zimbabwe: systemic inflammation during co-infection and after treatment for schistosomiasis. | We previously reported that treatment for schistosomiasis in persons infected with human immunodeficiency virus 1 (HIV-1) attenuated HIV replication as measured by plasma HIV RNA. We investigated systemic inflammation as measured by plasma levels of soluble tumor necrosis factor-alpha receptor II (sTNF-rII), interleukin-8, (IL-8), and IL-10 during schistosomiasis and HIV co-infection and after schistosomiasis treatment. The cohort was composed of 378 persons who were or were not infected with HIV-1, Schistosoma haematobium, or S. mansoni. Schistosomiasis-infected persons were randomized to receive praziquantel (40 mg/kg) at baseline or at the three-month follow-up. sTNF-rII and IL-8 were positively associated with schistosomiasis intensity as measured by circulating anodic antigen (CAA), regardless of HIV status. Interleukin-10 was positively associated with CAA in HIV-negative participants. IL-8 levels were higher in S. mansoni-infected individuals. Treatment for schistosomiasis caused a decrease in levels of sTNF-rII (P < 0.05) and IL-10 (P < 0.001). Our results indicate that schistosomiasis treatment may attenuate HIV replication by decreasing systemic inflammation. | 18,784,223 |
Challenges in routine implementation and quality control of rapid diagnostic tests for malaria--Rufiji District, Tanzania. | Rapid diagnostic tests (RDTs) represent an alternative to microscopy for malaria diagnosis and have shown high sensitivity and specificity in a variety of study settings. Current World Health Organization (WHO) guidelines for quality control of RDTs provide detailed instructions on pre-field testing, but offer little guidance for quality assurance once RDTs are deployed in health facilities. From September 2006 to April 2007, we introduced a histidine-rich protein II (HRP2)-based RDT (Paracheck) for suspected malaria cases five years of age and older in nine health facilities in Rufiji District, Tanzania, to assess sensitivity and specificity of RDTs in routine use at rural health facilities. Thick blood smears were collected for all patients tested with RDTs and stained and read by laboratory personnel in each facility. Thick smears were subsequently reviewed by a reference microscopist to determine RDT sensitivity and specificity. In all nine health facilities, there were significant problems with the quality of staining and microscopy. Sensitivity and specificity of RDTs were difficult to assess given the poor quality of routine blood smear staining. Mean operational sensitivity of RDTs based on reference microscopy was 64.8%, but varied greatly by health facility, range 18.8-85.9%. Sensitivity of RDTs increased with increasing parasite density. Specificity remained high at 87.8% despite relatively poor slide quality. Institution of quality control of RDTs based on poor quality blood smear staining may impede reliable measurement of sensitivity and specificity and undermine confidence in the new diagnostic. There is an urgent need for the development of alternative quality control procedures for rapid diagnostic tests that can be performed at the facility level. | 18,784,230 |
Acute respiratory distress syndrome in a case of Plasmodium ovale malaria. | Acute respiratory distress syndrome is a well-known complication in Plasmodium falciparum infection. It is less frequently described in Plasmodium vivax, and only one case is reported in Plasmodium ovale. Here we present the second description of this pulmonary complication in a P. ovale acute infection. | 18,784,231 |
Distinctive epidemiologic and clinical features of common krait (Bungarus caeruleus) bites in Sri Lanka. | A prospective study was designed to define epidemiologic and clinical features of krait bites to improve diagnosis, management, and prevention. Among 762 cases of venomous snake bites admitted to 10 Sri Lankan hospitals in which the snake responsible was brought and identified, 88 (11.5%) were caused by common kraits (Bungarus caeruleus). Bites were: most frequent in September through November. Distinctive features of B. caeruleus bites (compared with bites by other species in parentheses) were bitten while sleeping on the ground, 100% (1%); indoors, 100% (49%); between 2300 and 0500 hours, 100% (3%). Only 13% of krait victims were bitten on their lower limbs (82%), only 9% had local swelling (in all cases mild) at the site of the bite (93%), 64% developed respiratory paralysis (2%), and 91% experienced (often severe) abdominal pain (10%). Case fatality was 6% (3%). This distinctive pattern of epidemiology and symptoms will aid clinical recognition (syndromic diagnosis) and prevention of krait bite envenoming. | 18,784,244 |
Inducible rodent models of acquired podocyte diseases. | Glomerular diseases remain the leading cause of chronic and end-stage kidney disease. Significant advances in our understanding of human glomerular diseases have been enabled by the development and better characterization of animal models. Diseases of the glomerular epithelial cells (podocytes) account for the majority of proteinuric diseases. Rodents have been extensively used experimentally to better define mechanisms of disease induction and progression, as well as to identify potential targets and therapies. The development of podocyte-specific genetically modified mice has energized the research field to better understand which animal models are appropriate to study acquired podocyte diseases. In this review we discuss inducible experimental models of acquired nondiabetic podocyte diseases in rodents, namely, passive Heymann nephritis, puromycin aminonucleoside nephrosis, adriamycin nephrosis, liopolysaccharide, crescentic glomerulonephritis, and protein overload nephropathy models. Details are given on the model backgrounds, how to induce each model, the interpretations of the data, and the benefits and shortcomings of each. Genetic rodent models of podocyte injury are excluded. | 18,784,259 |
Combined knockout of collecting duct endothelin A and B receptors causes hypertension and sodium retention. | The collecting duct (CD) endothelin (ET) system regulates blood pressure (BP) and Na excretion. CD-specific knockout (KO) of ET-1 causes hypertension, CD-specific KO of the ETA receptor does not alter BP, while CD-specific KO of the ETB receptor increases BP to a lesser extent than CD ET-1 KO. These findings suggest a paracrine role for CD-derived ET-1; however, they do not exclude compensation for the loss of one ET receptor by the other. To examine this, mice with CD-specific KO of both ETA and ETB receptors were generated (CD ETA/B KO). CD ETA/B KO mice excreted less urinary Na than controls during acute or chronic Na loading. Urinary aldosterone excretion and plasma renin concentration were similar during Na intake and both fell comparably during Na loading. On a normal sodium diet, CD ETA/B KO mice had increased BP, which increased further with high salt intake. The degree of BP elevation during normal Na intake was similar to CD ET-1 KO mice and higher than CD ETB KO animals. During 1 wk of Na loading, CD ETA/B KO mice had higher BPs than CD ETB KO, while BP was less than CD ET-1 KOs until the latter days of Na loading. These studies suggest that 1) CD ETA/B deficiency causes salt-sensitive hypertension, 2) CD ETA/B KO-associated Na retention is associated with failure to suppress the renin-angiotensin-aldosterone system, and 3) CD ETA and ETB receptors exerts a combined hypotensive effect that exceeds that of either receptor alone. | 18,784,261 |
Single-channel analysis of functional epithelial sodium channel (ENaC) stability at the apical membrane of A6 distal kidney cells. | Epithelial sodium channels (ENaC) play an essential role in maintaining total body fluid and electrolyte homeostasis. As such, abnormal expression of ENaC at the cell surface is linked to several important human diseases. Although the stability of ENaC subunits has been extensively studied by protein biochemical analysis, the half-life of the functional channel in the apical membrane remains controversial. Because the functional stability of the multisubunit channel may be more physiologically relevant than the stability of individual subunit proteins, we performed studies of functional ENaC channels using A6 epithelial cells, a Xenopus laevis distal nephron cell line. We recorded single-channel activity in over 400 cells with the translation blockers cycloheximide (CHX) or puromycin, as well as the intracellular protein trafficking inhibitors brefeldin A (BFA) or nocodazole. Our cell-attached, single-channel recordings allow us to quantify the channel density in the apical membrane, as well as to determine channel open probability (Po) from control (untreated) cells and from cells at different times of drug treatment. The data suggest that the half-life of ENaC channels is approximately 3.5 h following puromycin, BFA, and nocodazole treatment. Furthermore, these three drugs had no significant effect on the Po of ENaC for at least 6 h after exposure. A decrease in apical channel number and Po was observed following 2 h of CHX inhibition of protein synthesis, and the apparent channel half-life was closer to 1.5 h following CHX treatment. Treatment of cells with the translation inhibitors does not alter the expression of the protease furin, and therefore changes in protease activity cannot explain changes in ENaC Po. Confocal images show that BFA and nocodazole both disrupt most of the Golgi apparatus after 1-h exposure. In cells with the Golgi totally disrupted by overnight exposure to BFA, 20% of apical ENaC channels remained functional. This result suggests that ENaC is delivered to the apical membrane via a pathway that might bypass the Golgi vesicular trafficking pathway, or that there might be two pools of channels with markedly different half-lives in the apical membrane. | 18,784,262 |
Long-term retention explained by a model of short-term learning in the adaptive control of reaching. | Extensive theoretical, psychophysical, and neurobiological work has focused on the mechanisms by which short-term learning develops into long-term memory. Better understanding of these mechanisms may lead to the ability to improve the efficiency of training procedures. A key phenomenon in the formation of long-term memory is the effect of over learning on retention-discovered by Ebbinghaus in 1885: when the initial training period in a task is prolonged even beyond what is necessary for good immediate recall, long-term retention improves. Although this over learning effect has received considerable attention as a phenomenon in psychology research, the mechanisms governing this process are not well understood, and the ability to predict the benefit conveyed by varying degrees of over learning does not yet exist. Here we studied the relationship between the duration of an initial training period and the amount of retention 24 h later for the adaptation of human reaching arm movements to a novel force environment. We show that in this motor adaptation task, the amount of long-term retention is predicted not by the overall performance level achieved during the training period but rather by the level of a specific component process in a multi-rate model of short-term memory formation. These findings indicate that while multiple learning processes determine the ability to learn a motor adaptation, only one provides a gateway to long-term memory formation. Understanding the dynamics of this key learning process may allow for the rational design of training and rehabilitation paradigms that maximize the long-term benefit of each session. | 18,784,273 |
Different hormonal regulation of cellular differentiation and function in nucellar projection and endosperm transfer cells: a microdissection-based transcriptome study of young barley grains. | Nucellar projection (NP) and endosperm transfer cells (ETC) are essential tissues in growing barley (Hordeum vulgare) grains, responsible for nutrient transfer from maternal to filial tissues, endosperm/embryo nutrition, and grain development. A laser microdissection pressure catapulting-based transcriptome analysis was established to study NP and ETC separately using a barley 12K macroarray. A major challenge was to isolate high-quality mRNA from preembedded, fixed tissue while maintaining tissue integrity. We show that probes generated from fixed and embedded tissue sections represent largely the transcriptome (>70%) of nonchemically treated and nonamplified references. In NP, the top-down gradient of cellular differentiation is reflected by the expression of C3HC4-type ubiquitin ligases and different histone genes, cell wall biosynthesis and expansin/extensin genes, as well as genes involved in programmed cell death-related proteolysis coupled to nitrogen remobilization, indicating distinct areas simultaneously undergoing mitosis, cell elongation, and disintegration. Activated gene expression related to gibberellin synthesis and function suggests a regulatory role for gibberellins in establishment of the differentiation gradient. Up-regulation of plasmalemma-intrinsic protein and tonoplast-intrinsic protein genes indicates involvement in nutrient transfer and/or unloading. In ETC, AP2/EREBP-like transcription factors and ethylene functions are transcriptionally activated, a response possibly coupled to activated defense mechanisms. Transcriptional activation of nucleotide sugar metabolism may be attributed to ascorbate synthesis and/or cell wall biosynthesis. These processes are potentially controlled by trehalose-6-P synthase/phosphatase, as suggested by expression of their respective genes. Up-regulation of amino acid permeases in ETC indicates important roles in active nutrient uptake from the apoplastic space into the endosperm. | 18,784,282 |
Presynaptic type III neuregulin 1 is required for sustained enhancement of hippocampal transmission by nicotine and for axonal targeting of alpha7 nicotinic acetylcholine receptors. | Both the neuregulin 1 (Nrg1) and alpha7 nicotinic acetylcholine receptor (alpha7*nAChRs) genes have been linked to schizophrenia and associated sensory-motor gating deficits. The prominence of nicotine addiction in schizophrenic patients is reflected in the normalization of gating deficits by nicotine self-administration. To assess the role of presynaptic type III Nrg1 at hippocampal-accumbens synapses, an important relay in sensory-motor gating, we developed a specialized preparation of chimeric circuits in vitro. Synaptic relays from Nrg1(tm1Lwr) heterozygote ventral hippocampal slices to wild-type (WT) nucleus accumbens neurons (1) lack a sustained, alpha7*nAChRs-mediated phase of synaptic potentiation seen in comparable WT/WT circuits and (2) are deficient in targeting alpha7*nAChRs to presynaptic sites. Thus, selective alteration of the level of presynaptic type III Nrg1 dramatically affects the modulation of glutamatergic transmission at ventral hippocampal to nucleus accumbens synapses. | 18,784,291 |
A novel Na+ channel splice form contributes to the regulation of an androgen-dependent social signal. | Na(+) channels are often spliced but little is known about the functional consequences of splicing. We have been studying the regulation of Na(+) current inactivation in an electric fish model in which systematic variation in the rate of inactivation of the electric organ Na(+) current shapes the electric organ discharge (EOD), a sexually dimorphic, androgen-sensitive communication signal. Here, we examine the relationship between an Na(+) channel (Na(v)1.4b), which has two splice forms, and the waveform of the EOD. One splice form (Na(v)1.4bL) possesses a novel first exon that encodes a 51 aa N-terminal extension. This is the first report of an Na(+) channel with alternative splicing in the N terminal. This N terminal is present in zebrafish suggesting its general importance in regulating Na(+) currents in teleosts. The extended N terminal significantly speeds fast inactivation, shifts steady-state inactivation, and dramatically enhances recovery from inactivation, essentially fulfilling the functions of a beta subunit. Both splice forms are equally expressed in muscle in electric fish and zebrafish but Na(v)1.4bL is the dominant form in the electric organ implying electric organ-specific transcriptional regulation. Transcript abundance of Na(v)1.4bL in the electric organ is positively correlated with EOD frequency and lowered by androgens. Thus, shaping of the EOD waveform involves the androgenic regulation of a rapidly inactivating splice form of an Na(+) channel. Our results emphasize the role of splicing in the regulation of a vertebrate Na(+) channel and its contribution to a known behavior. | 18,784,298 |
Identification of a novel nurr1-interacting protein. | The orphan nuclear receptor Nurr1 is required for the development of ventral mesencephalic dopaminergic neurons in mice. One of the possible mechanisms that might contribute to the regulation activity of Nurr1 is through interaction with other proteins. To identify potential partners of Nurr1, we screened a yeast two-hybrid library from developing mouse embryonic mesencephalon with the Nurr1 ligand-binding domain (NLBD). We identified a novel interacting protein, termed the Nurr1-interacting protein (NuIP). We demonstrate that it specifically interacts with NLBD using the mammalian two-hybrid assay and coimmunoprecipitation studies in MN9D cells. In addition, we show that NuIP interacts with Nurr1 in lysates from substantia nigra. Coexpression of NuIP with Nurr1 results in potentiation of the transcriptional activity of Nurr1 on an nerve growth factor inducible-B response element reporter, as well as reporters driven by the endogenous tyrosine hydroxylase promoter. The mechanism underlying the regulatory action of NuIP on Nurr1 is demonstrated to be through assembly of distinct helical domains of the NLBD. Using a NuIP specific antibody, we show that expression of NuIP protein is mainly colocalized with Nurr1 in adult midbrain dopaminergic neurons. Finally, we demonstrate that suppression of NuIP expression in MN9D cells by NuIP-specific small interfering RNA leads to decreased cell division and decreased expression of a Nurr1 target gene, the dopamine transporter. These results suggest NuIP interacts with and positively regulates the activity of Nurr1 protein and modulates the phenotype of dopaminergic cells. | 18,784,308 |
Effects of a health behavior change model--based HIV/STI prevention intervention on condom use among heterosexual couples: a randomized trial. | This study examines an intervention for heterosexual couples to prevent human immunodeficiency virus/sexually transmitted infections. It also evaluates the effect of the intervention, which is based on current models of health behavior change, on intermediate outcomes (individual and relationship factors) and consistency of condom use. Eligible couples were administered a baseline interview and randomized to either a 3-session theory-based intervention or a 1-session standard of care comparison condition. Men and women completed 3-month interviews; only women completed 6-month interviews. No significant intervention effect on condom use was found among couples at 3 months (n = 212) or among women (n = 178) at 6 months. However, condom use increased significantly between baseline and 3 months and baseline and 6 months for participants in both treatment conditions. Intervention effects on condom use self-efficacy were found at 3 months and 6 months and on health-protective communication at 3 months. These findings provide valuable information for the design of future studies to help disentangle the effects of intervening with couples. | 18,784,350 |
Effects of local mRNA structure on posttranscriptional gene silencing. | Antisense oligodeoxynucleotides (AONs) and short interfering RNAs (siRNAs) effect posttranscriptional gene silencing (PTGS) by hybridizing to an mRNA and then directing its cleavage. To understand the constraints that mRNA structure imposes on AON- vs. siRNA-mediated PTGS, AON- and siRNA-mediated cleavage of defined mRNA structures was monitored in Drosophila embryo whole-cell lysates. We observed that AON-directed cleavage was approximately 3-fold faster than cleavage with a siRNA directed to the same target site. Furthermore, and unexpectedly, AON-mediated cleavage was found to be much less fastidious with respect to target sequence accessibility, as measured by the presence of unpaired nucleotides, than a corresponding siRNA. Nonetheless, in vivo, siRNAs silenced their mRNA target at least 2-fold more efficiently than the corresponding AON. These seemingly contradictory results suggested that additional, as yet undefined factors play an important role in regulating PTGS efficiency in vivo. We used a well defined RNA-binding protein, alphaCP, and its corresponding high-affinity RNA-binding site to explore this hypothesis. We found that prebound alphaCP effectively blocked AON-mediated cleavage of the RNA-binding site compared with cleavage of the site in the absence of alphaCP. We conclude that higher-order structures formed by RNA and bound proteins play an important role in determining the efficiency of AON-directed PTGS. We hypothesize that strategies aimed at removing RNA-binding proteins might significantly improve AON-mediated PTGS in vivo. | 18,784,366 |
[Vaginal birth after one previous cesarean section]. | To evaluate the frequency of different modes of delivery after one previous cesarean section and those factors which may influence mode of delivery. During the study period (1.1.2001-31.12.2005) 925 women with a previous cesarean section and a following singleton pregnancy were identified and included. Information regarding mode of delivery, induction of labor, instrumental delivery, the urgency and indications for first and second cesarean section, birth weight and Apgar scores were collected retrospectively. Trial of labor (TOL) was initiated for 564 women of which 61% were successful while 39% delivered by an emergent cesarean section. In total, 346 women delivered vaginally (37%), 341 women (37%) delivered with an elective cesarean section and 238 (26%) underwent an emergency cesarean section. The VBAC rate increased during the study period, from 35% to 46%. Women who underwent an elective cesarean section due to fetal malpresentation (most often breech) in their first pregnancy were significantly more likely to have a successful VBAC in their second pregnancy (53%) compared with women who had an elective cesarean section for any other indication (21%) (p<0.0001). Uterine rupture occurred in six women (1%) during TOL, five underwent an emergency cesarean section and had healthy infants while there was one intrapartum fetal death. No correlation was found between birth mode and Apgar scores at five minutes. Perinatal mortality rate was 5,4 per thousand. Trial of labor was less likely to succeed if the infant's birth weight was >4000 grams compared with <4000 grams (p<0.01). The results of this study indicate that VBAC is a safe option for women with a history of one previous cesarean section while in the hospital setting where there are resources for an immediate cesarean section. Vaginal birth after cesarean section (VBAC), uterine rupture, perinatal mortality rate. Correspondence: Hildur Hardardóttir, hhard@landspitali.is. | 18,784,385 |
Striated myogenesis and peristalsis in the fetal murine esophagus occur without cell migration or interstitial cells of Cajal. | Esophageal striated myogenesis progresses differently from appendicular myogenesis, but the mechanism underlying this process is incompletely understood. Early theories of transdifferentiation of smooth muscle into striated muscle are not supported by transgenic fate-mapping experiments; however, the origin of esophageal striated muscle remains unknown. To better define the process of striated myogenesis, we examined myogenesis in murine fetal cultured esophageal whole-organ explants. Embryonic day 14.5 (E14.5) esophagi maintained a functional contractile phenotype for up to 7 days in culture. Striated myogenesis, as evidenced by myogenin expression, proceeded in a craniocaudal direction along the length of the esophagus. Esophageal length did not change during this process. Complete, but not partial, mechanical disruption of the rostral esophagus inhibited myogenesis distally. Addition of fibroblast growth factor-2 (FGF-2) to the culture media failed to inhibit striated myogenesis, but attenuated smooth muscle actin expression and reduced peristaltic activity. Inhibition of c-kit failed to inhibit peristalsis. These results suggest that striated myogenic precursors are resident along the entire length of the esophagus by day 14.5 and do not migrate along the esophagus after E14.5. Induction of myogenesis craniocaudally appears to require physical continuity of the esophagus and is not inhibited by FGF-2. Finally, peristalsis in E14.5 esophagi appears not to be regulated by interstitial cells of Cajal. | 18,784,410 |
Respiratory muscle strength predicts decline in mobility in older persons. | To test the hypothesis that respiratory muscle strength is associated with the rate of change in mobility even after controlling for leg strength and physical activity. Prospective study of 890 ambulatory older persons without dementia who underwent annual clinical evaluations to examine change in the rate of mobility over time. In a linear mixed-effect model adjusted for age, sex, and education, mobility declined about 0.12 unit/year, and higher levels of respiratory muscle strength were associated with a slower rate of mobility decline (estimate 0.043, SE 0.012, p < 0.001). Respiratory muscle strength remained associated with the rate of change in mobility even after controlling for lower extremity strength (estimate 0.036, SE 0.012, p = 0.004). In a model that included terms for respiratory muscle strength, lower extremity strength and physical activity together, all three were independent predictors of mobility decline in older persons. These associations remained significant even after controlling for body composition, global cognition, the development of dementia, parkinsonian signs, possible pulmonary disease, smoking, joint pain and chronic diseases. Respiratory muscle strength is associated with mobility decline in older persons independent of lower extremity strength and physical activity. Clinical interventions to improve respiratory muscle strength may decrease the burden of mobility impairment in the elderly. | 18,784,416 |
Monitoring neonatal regional cerebral oxygen saturation in clinical practice: value and pitfalls. | This review focuses on the clinical use of near infrared spectroscopy (NIRS) to assess brain oxygenation by the tissue oxygenation index (TOI), and monitoring regional cerebral oxygen saturation (rScO(2)), cerebral fractional tissue oxygen extraction (cFTOE), which is derived from rScO(2), and systemic oxygen saturation. Its precision and pitfalls are discussed. At this stage, it is clear that NIRS-monitored oxygenation of the brain by rScO(2) or TOI lacks the precision required to be used as a robust quantitative variable to monitor cerebral oxygenation. Intra- and especially interpatient variability are too large for this aim. On the other hand, when used merely as a trend monitor in the individual patient, substantial changes in rScO(2) or TOI and consequently of cFTOE, larger than the limits of agreement, can yield important clinical information that suggest an intervention. Since neonatal intensive care is for a substantial part 'brain orientated' this approach seems conceivable. This gives rise to the conclusion that NIRS-monitored TOI, rScO(2) and cFTOE increasingly will have a role in clinical practice as semiquantitative indicators of changes in cerebral oxygenation and oxygen extraction. Combination with other (cerebral) parameters such as amplitude-integrated EEG and blood pressure seems promising for further optimization of monitoring the immature brain. | 18,784,420 |
Endobronchial obstruction from an intubation stylet sheath. | Many clinicians intubate newborns using a stylet, but how many always check if the device is intact after use? We describe a case of endobronchial obstruction by a plastic sheath coating the metal stylet, and suggest ways to reduce the incidence of this serious iatrogenic complication. | 18,784,428 |
Resolution of severe macular edema in adult coats' disease with intravitreal triamcinolone and bevacizumab injection. | A 47 year old male patient visited our hospital with the chief complaint of deterioration of the visual acuity in the left eye. The fundus examination revealed thick hard exudates, multiple aneurysms and telangiectasias of the retinal vessels in the posterior pole. Fluorescein angiography demonstrated massive leakage over an area of the aneurysms. Optical coherence tomography (Stratus OCT; Zeiss-Humphrey, Dubin, CA) revealed diffuse and marked thickening of the retina. Laser photocoagulation was performed under the diagnosis of Coats' disease. However, the treatment could not be performed satisfactorily. On the first and 6th weeks, an intravitreal injection of bevacizumab and triamcinolone acetonide was administered, and laser photocoagulation was again attempted. The effectiveness of eachagent on retinal edema was evaluated at the follow-up performed at 1, 2, 5, 7, 10 weeks and 6 months after the injection. At one week after the intravitreal bevacizumab injection, there was no improvement. An intravitreal injection of triamcinolone acetonide was performed 6 weeks after the initial diagnosis,which resulted in a reduction in the thickness of the macular edema. Therefore, laser photocoagulation was performed sufficiently on telangiectasias. The follow-up at 6 months showed a relative increase in the macular edema, but there was reduced leakage from the telangiectasias compared with the previous angiograph. | 18,784,449 |
Early mortality among adults accessing antiretroviral treatment programmes in sub-Saharan Africa. | Two-thirds of the world's HIV-infected people live in sub-Saharan Africa, and more than 1.5 million of them die annually. As access to antiretroviral treatment has expanded within the region; early pessimism concerning the delivery of antiretroviral treatment using a large-scale public health approach has, at least in the short term, proved to be broadly unfounded. Immunological and virological responses to ART are similar to responses in patients treated in high-income countries. Despite this, however, early mortality rates in sub-Saharan Africa are very high; between 8 and 26% of patients die in the first year of antiretroviral treatment, with most deaths occurring in the first few months. Patients typically access antiretroviral treatment with advanced symptomatic disease, and mortality is strongly associated with baseline CD4 cell count less than 50 cells/mul and WHO stage 4 disease (AIDS). Although data are limited, leading causes of death appear to be tuberculosis, acute sepsis, cryptococcal meningitis, malignancy and wasting syndrome. Mortality rates are likely to depend not only on the care delivered by antiretroviral treatment programmes, but more fundamentally on how advanced disease is at programme enrollment and the quality of preceding healthcare. In addition to improving delivery of antiretroviral treatment and providing it free of charge to the patient, strategies to reduce mortality must include earlier diagnosis of HIV infection, strengthening of longitudinal HIV care and timely initiation of antiretroviral treatment. Health systems delays in antiretroviral treatment initiation must be minimized, especially in patients who present with advanced immunodeficiency. | 18,784,453 |
Evaluation of the influence of location of osseointegrated implants associated with mandibular removable partial dentures. | The aim of this research was to assess, by means of, the bi-dimensional finite element method, the best implant location in the alveolar edge, through stress distribution and support structure displacement of a distal extension removable partial denture associated with an osseointegrated implant of 10.0 x .75 mm, acting as abutment for the denture base. Five models in sagittal cut were used to represent: model A-hemi arch containing natural tooth 33 and the distal alveolar edge; model B-similar to model A, but with a conventional removable partial denture to replace the absent teeth; model C (MC)-similar to the previous one, with an implant in the distal region of the edge under the denture base; model D-similar to MC, with the implant in the central region of the edge; model E-similar to MC, with an implant in the mesial region of the edge. With the aid of the finite element program ANSYS 8.0, the models were loaded with strictly vertical forces of 50 N on each cusp tip. Displacement and von Mises Maps were plotted for visualization of results. The introduction of implant diminished the tendency of intrusion of the removable partial denture in all situations. The maximum stress was observed on implant in all situations. Approximating implant in direction of support teeth was benefit for stress distribution. Model D presented the lowest value for maximum tendency to displacement when compared with those found in the other models; model E demonstrated better relief with regard to demand from the abutment tooth; locating the implant near of the abutment tooth influenced positively the distribution of stresses on the analyzed structures. | 18,784,528 |
Scanning electron microscope evaluation of vertical and horizontal discrepancy in cast copings for single-tooth implant-supported prostheses. | Despite careful attention to waxing, investing, and casting, marginal discrepancies are inevitable. Vertical and horizontal discrepancies can result in crestal bone resorption, peri-implantitis, and loss of osseointegration. The aim of this study was to evaluate marginal gap and overhang in 3 casting techniques for implant framework fabrication. A total of 24 frameworks, 8 each with the Burn-out Cap (ITI; Straumann) (group BC), with Impression Cap (ITI; Straumann) (group IC), and with conventional wax-up technique (group WX) were fabricated. All specimens were waxed on the analog abutments and cast with Type IV gold alloy. All castings were fixed on the analog abutments with cyanoacrylate and embedded in acrylic resin. Specimens were sectioned and prepared for scanning electron microscope evaluation. Frameworks were analyzed for vertical and horizontal discrepancies with x200 magnification (scanning electron microscopy). Data were analyzed statistically by multivariate analysis and the post hoc tests (alpha = 0.05). The vertical discrepancy measurements for the 3 groups showed mean values of 53.74 +/- 11.0 mum, 63.6 +/- 13.2 mum, and 50.1 +/- 17.3 mum, respectively. The interfacial gap differences were not statistically significant in all groups (P > 0.05). Waxing the frameworks with impression caps significantly increased the horizontal discrepancy at the interfaces (P < 0.001). Within the limitations of this experiment, it was demonstrated that the vertical discrepancy of the frameworks made with the 3 techniques were comparable in lack of accuracy with each other. Although conventional waxing produced the least horizontal discrepancy, the difference with burn-out cap group was not statistically different. | 18,784,530 |
Sinus augmentation complications: etiology and treatment. | Sinus augmentation, either osteotome or lateral window approach, is a predictable procedure to augment vertical height that allows for proper implant placement in areas with previous limited restorative options. Like any surgical procedures, there is always a risk of encountering either intrasurgical or postsurgical complications. A Medline literature search of articles published from 1984 to 2006 related to complications following sinus augmentation were selected and analyzed. To make it easier for understanding, sinus augmentation complications were classified into following categories: systemic disease and mediations related; anatomy and surgical procedure related; sinus pathology related; infection related; and prosthetic related. Depending on the source or cause of complication, treatment may include palliative approach to surgical intervention. This article will review a newly proposed complication classification, discuss treatment modalities for each encountered complication and propose methods to avoid these complications. | 18,784,534 |
The relationship between attorney involvement, claim duration, and workers' compensation costs. | To determine the relationship between attorney involvement, claim duration and workers' compensation claim costs. We identified and compared 738 claims with attorney involvement and 6191 claims without attorney involvement submitted by individuals injured between August 1, 2003 and July 31, 2004 whose claims were paid by the Louisiana Workers' Compensation Corporation (LWCC). At the time of assessment (March 20, 2006), 97.7% of claims not involving attorneys and 57.5% of claims involving attorneys were closed (resolved). After controlling for lost time (temporary/total days paid), attorney involvement was associated with consistently higher medical, indemnity and claims handling costs, as well as increasing claim duration (accident date to closing date). Attorney involvement in workers' compensation claims is associated with increasing claims duration and costs. | 18,784,549 |
Rotator cuff syndrome: personal, work-related psychosocial and physical load factors. | To identify factors associated with rotator cuff syndrome (RCS) among active workers. Seven hundred thirty-three workers in 12 worksites participated in a cross-sectional study with individual structured physical and psychosocial health interviews, physical examinations, and exposure assessments of biomechanical factors. Work organization, including job content or structural constraints, was assessed at the departmental level. Multivariable logistic modeling was used. Fifty-five subjects (7.5%) had RCS. Cases were more likely to report low job security (P < 0.04) and to have very high job structural constraints (P < 0.03). Age and body mass index were marginally significant. Upper arm flexion >or= 45 degrees >or= 15% of time and either duty cycle of forceful exertions >or=9% time (odds ratio = 2.43, 95% CI = 1.04 to 5.68) or forceful pinch >0% [odds ratio = 2.66, 95% CI = 1.26 to 5.59] were significant risk factors. Long duration of shoulder flexion and forceful exertion (especially pinch) in a job are significant risk factors for RCS. Work organization may impact physical and psychosocial exposures and should be further explored. | 18,784,555 |
Hepatoprotection and lethality rescue by histone deacetylase inhibitor valproic acid in fatal hemorrhagic shock. | Pharmacological histone deacetylase (HDAC) inhibitors, such as known anticonvulsant valproic acid (VPA), demonstrate cytoprotective effects and increase acetylation of nuclear histones, promoting transcriptional activation of deregulated genes. Therefore, we examined protective effects of VPA administration in lethal hemorrhage and analyzed the patterns of hepatic histone acetylation. Male Wistar Kyoto rats were pretreated with VPA (n = 10) and 2-methyl-2-pentenoic acid (2M2P), structural VPA analog with limited HDAC inhibiting activity (2M2P; n = 8), at 300 mg/kg/dose, administered subcutaneously, 24 hour and immediately before lethal, if untreated, hemorrhage was induced by removing the 60% of total blood volume. Both drugs were dissolved in normal saline (NS) and rats pretreated with corresponding volume of NS served as control group (n = 8). Time to death, the degree of histone acetylation in liver, HDAC activity and markers of cytotoxicity (alpha-glutathione S-transferase, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and lactate), and apoptosis were analyzed. VPA-pretreated animals demonstrated five-fold increase in survival duration. At 12 hours posthemorrhage, 70% (VPA) and 12% (2M2P) pretreated rats were alive versus 0% in NS group. Hyperacetylation of histones H2A, H3, and H4 indicated the presence of active genes and correlated with survival (VPA > 2M2P > NS). Hemorrhage-induced increases in lactate, lactate dehydrogenase, aspartate aminotransferase, and alanine aminotransferase were alleviated by VPA. Moreover, alpha-glutathione S-transferase release, indicative of liver damage, was completely abolished. VPA offers considerable protection in severe hemorrhagic shock. The role of HDAC inhibition is suggested in mediating prosurvival actions of VPA. | 18,784,568 |
Postmortem computed tomography as an adjunct to autopsy for analyzing fatal motor vehicle crash injuries: results of a pilot study. | Detailed fatal injury data after fatal motor vehicle crashes (MVC) are necessary to improve occupant safety and promote injury prevention. Autopsy remains the principle source of detailed fatal injury data. However, procedure rates are declining because of a range of technical, ethical, and religious concerns. Postmortem computed tomography (PMCT) is a potential alternative or adjunct to autopsy which is increasingly used by forensic researchers. However, there are only limited data regarding the utility of PMCT for analysis of fatal MVC injuries. We performed whole body PMCT and autopsy on six subjects fatally injured in MVC in a single county in Michigan. All injuries detected by either method were coded using the Abbreviated Injury Scale (AIS). Severe injuries, defined as AIS 3 or higher (AIS 3+), were tallied for each forensic procedure to allow a comparison of relative diagnostic performance. A total of 46 AIS 3+ injuries were identified by autopsy and PMCT for these cases. The addition of PMCT to autopsy increased overall detection of AIS 3+ injuries (all types) by 28%. PMCT detected 27% more AIS 3+ skeletal injuries than autopsy but 25% less soft tissue injuries. Use of PMCT improves the detection of AIS 3+ injuries after fatal MVC compared with isolated use of autopsy and also produces a highly detailed permanent objective record. PMCT appears to improve detection of skeletal injury compared with autopsy but is less sensitive than autopsy for the detection of AIS 3+ soft tissue injuries. Neither autopsy nor PMCT identified all AIS 3+ injuries revealed by the combination of the two methodologies. This suggests that PMCT should be used as an adjunct to autopsy rather than a replacement whenever feasible. | 18,784,581 |
Intramedullary fixation of failed plated femoral diaphyseal fractures: are bone grafts necessary? | Nonunited fracture shaft femur after plate fixation is a common problem in third world countries because of economic reasons. Management of such a problem is still controversial and is associated with many surgical details, due not only to the nonunited fracture itself, but also to the broken implant which is not easy to remove. This study is a randomized prospective study presenting 40 patients with aseptic nonunited fracture shaft femur associated with failed plating managed by the removal of hardware, and intramedullary fixation using an interlocking nail with or without autogenous iliac bone graft. There was no statistically significant difference between patients with and without iliac autogenous bone graft regarding the demographic data, the preoperative condition, and the postoperative course including time needed for bone union and return to work. The statistically significant difference was in the intraoperative blood loss and the duration of surgery with less blood loss and shorter duration of surgery occurring in the group treated by reamed intramedullary nail without iliac bone graft. In cases with aseptic nonunited fracture shaft femur after failed plating, intramedullary reamed nailing without autogenous bone graft produced similar results as with bone graft, but with less operating time and blood loss. | 18,784,586 |
Blunt solid organ injury: do adult and pediatric surgeons treat children differently? | The management of blunt solid organ injury (SOI) in children may differ depending on the treating facility. These differences, however, may not reflect the individual surgeon's treatment philosophy. To investigate differences in management, adult and pediatric surgeons were presented the same hypothetical pediatric trauma "patient" and asked a series of treatment questions. By using an internet-based survey, members of American Association for the Surgery of Trauma, American Academy of Pediatrics, and Eastern Association of the Surgery of Trauma were invited to participate anonymously. Surgeons who "never or rarely saw children" and those who "would transfer the patient to another facility" were excluded. Demographic, educational, and practice data were collected. Scenarios of increasing complexity were presented with CT images (isolated SOI, multiple SOI, and SOI with intracranial hemorrhage [ICH]). For each scenario, respondents were asked if they would initially manage the patient nonoperatively, pursue angiography, or operate. Scenarios were repeated with the addition of a CT "blush." For patients managed nonoperatively, respondents were asked their transfusion threshold needed to operate. Responses were compared using exact chi tests and risk ratios. Two hundred eighty-one surgeons (114 pediatric, 167 adult) were included. For all scenarios, adult surgeons were more likely to operate or pursue embolization than their pediatric colleagues (RR: 8.6 SOI, 14.8 multiple SOI, 17.9 SOI with ICH). Adult surgeons were also more likely to consider any transfusion a failure (13.3% vs. 1.2%, p < 0.01) and had a much lower transfusion threshold. When presented with the identical clinical scenario, adult trauma surgeons are less likely than pediatric surgeons to pursue nonoperative management of pediatric solid organ injuries and are more conservative in their willingness to transfuse. | 18,784,587 |
Subpopulation estimates from the HIV incidence surveillance system--United States, 2006. | CDC has created an HIV incidence surveillance system in selected areas of the United States as a component of its national human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) reporting system. The purpose of the new system is to estimate the number of new HIV infections occurring each year in the United States. Initial results published recently for 2006 showed that 73% of new infections were in males, 45% were in blacks, and 53% were in men who have sex with men (MSM). To provide additional subpopulation estimates by age group, race/ethnicity, and HIV transmission category, CDC conducted a more detailed analysis of data from the new surveillance system. The results indicated that, in 2006, of new HIV infections among males, 72% were in MSM. Among MSM with new infections, 46% were white, 35% were black, and 19% were Hispanic. Among MSM aged 13-29 years, the number of new HIV infections in blacks (5,220) was 1.6 times the number in whites (3,330) and 2.3 times the number in Hispanics (2,300). Among females, the predominant HIV transmission category was high-risk heterosexual contact, which accounted for 80% of new infections. The HIV incidence rate for black females was 14.7 times the rate for white females, and the rate for Hispanic females was 3.8 times the rate for white females. MSM (of all races), blacks, and Hispanics were represented disproportionately in 2006 among those with new HIV infections. The new incidence data will help guide local, state, and national intervention measures tailored to those populations at greatest risk for HIV infection. | 18,784,639 |
Recent Arctic warming vertical structure contested. | The vertical structure of the recent Arctic warming contains information about the processes governing Arctic climate trends. Graversen et al. argue, on the basis of ERA-40 reanalysis data, that a distinct maximum in 1979-2001 warm-season (April-October) Arctic temperature trends appears around 3 km above ground. Here we show that this is due to the heterogeneous nature of the data source, which incorporates information from satellites and radiosondes. Radiosonde data alone suggest the warming was strongest near ground. | 18,784,660 |
A Mott insulator of fermionic atoms in an optical lattice. | Strong interactions between electrons in a solid material can lead to surprising properties. A prime example is the Mott insulator, in which suppression of conductivity occurs as a result of interactions rather than a filled Bloch band. Proximity to the Mott insulating phase in fermionic systems is the origin of many intriguing phenomena in condensed matter physics, most notably high-temperature superconductivity. The Hubbard model, which encompasses the essential physics of the Mott insulator, also applies to quantum gases trapped in an optical lattice. It is therefore now possible to access this regime with tools developed in atomic physics. However, an atomic Mott insulator has so far been realized only with a gas of bosons, which lack the rich and peculiar nature of fermions. Here we report the formation of a Mott insulator of a repulsively interacting two-component Fermi gas in an optical lattice. It is identified by three features: a drastic suppression of doubly occupied lattice sites, a strong reduction of the compressibility inferred from the response of double occupancy to an increase in atom number, and the appearance of a gapped mode in the excitation spectrum. Direct control of the interaction strength allows us to compare the Mott insulating regime and the non-interacting regime without changing tunnel-coupling or confinement. Our results pave the way for further studies of the Mott insulator, including spin-ordering and ultimately the question of d-wave superfluidity. | 18,784,720 |
Upward migration of Vesuvius magma chamber over the past 20,000 years. | Forecasting future eruptions of Vesuvius is an important challenge for volcanologists, as its reawakening could threaten the lives of 700,000 people living near the volcano. Critical to the evaluation of hazards associated with the next eruption is the estimation of the depth of the magma reservoir, one of the main parameters controlling magma properties and eruptive style. Petrological studies have indicated that during past activity, magma chambers were at depths between 3 and 16 km (refs 3-7). Geophysical surveys have imaged some levels of seismic attenuation, the shallowest of which lies at 8-9 km depth, and these have been tentatively interpreted as levels of preferential magma accumulation. By using experimental phase equilibria, carried out on material from four main explosive events at Vesuvius, we show here that the reservoirs that fed the eruptive activity migrated from 7-8 km to 3-4 km depth between the ad 79 (Pompeii) and ad 472 (Pollena) events. If data from the Pomici di Base event 18.5 kyr ago and the 1944 Vesuvius eruption are included, the total upward migration of the reservoir amounts to 9-11 km. The change of preferential magma ponding levels in the upper crust can be attributed to differences in the volatile content and buoyancy of ascending magmas, as well as to changes in local stress field following either caldera formation or volcano spreading. Reservoir migration, and the possible influence on feeding rates, should be integrated into the parameters used for defining expected eruptive scenarios at Vesuvius. | 18,784,723 |
Microalbuminuria: do we need a new threshold? | Microalbuminuria (30-300 mg of albumin/24 h) is a well-known independent risk factor for kidney and cardiovascular disease and of mortality in diabetic, hypertensive and in the general population. However, recent studies indicate that increased risk is observed at levels of albuminuria much lower than those currently employed to define microalbuminuria. Such low levels were shown to predict heart disease and death, independent of age, sex, renal function, diabetes, hypertension and lipids, in subjects with cardiovascular disease, hypertension and in the general population; as well as to predict progression to hypertension. Correction of obesity and metabolic derangements lowered levels of albuminuria below 30 mg/24 h to levels not associated with increased risk (5-7 mg/24 h). Despite the lack of outcome studies, there is substantial evidence to indicate that the threshold for defining microalbuminuria (that is, albuminuria associated with increased risk) should be lowered by nearly three to four-fold from the currently defined threshold. It would be advisable that clinical scores and future guidelines would consider including microalbuminuria at the lower rates as an independent risk factor, and as an indication for implementing early intervention. Unfortunately, and despite the abundance of evidence, albuminuria measurements are still underutilized in clinical practice. | 18,784,737 |
CSB protein is (a direct target of HIF-1 and) a critical mediator of the hypoxic response. | Cockayne syndrome (CS) is a rare genetic disease characterized by neurological problems, growth failure and premature ageing. Many of these features cannot simply be ascribed to the defect that CS cells display during transcription-coupled repair. Here, we show that CSB mutant cells are unable to react to hypoxic stimuli by properly activating the hypoxia-inducible factor-1 (HIF-1) pathway, a defect that is further enhanced in the event of a concomitant genotoxic stress. Furthermore, we show that CSB expression is under the control of HIF-1 and has a critical function during hypoxic response by redistributing p300 between HIF-1 and p53. Altogether, our data demonstrate that CSB is part of a feedback loop mechanism that modulates the biological functions of p53. The outcome of this study provides new insights into the understanding of the molecular basis of the CS phenotype and the involvement of the CSB protein in the hypoxic response pathway. | 18,784,753 |
The influence of predation on the chronic response of Artemia sp. populations to a toxicant. | Environmental risk assessment of contaminants is conventionally based on toxic effects assessed in organism-level test systems. We suggest that, for the prediction of toxicant effects, population- and community-level effects should be considered. The aim of this study was to investigate how predation could alter a prey population's response to a toxicant to reveal effects at population and community levels.Populations of the brine shrimp Artemia sp. were maintained in the laboratory with and without simulated predation. Individuals were exposed for 1 h to the pyrethroid insecticide esfenvalerate (0, 0.01, 0.04 and 0.08 microg L(-1)) and subsequently observed for 6 weeks.Unpredated exposed populations showed a reduced population density compared with the control. However, even at the highest concentration of insecticide, populations were sustained until the end of the experiment. The lower density in the exposed populations led to reduced competition and subsequently to enhanced development of surviving individuals and an increased proportion of young individuals. In contrast, the combination of predation and short-term toxicant exposure at concentrations of 0.04 and 0.08 microg L(-1) produced extinction of the populations after 39 and 32 days of exposure, respectively.Synthesis and applications. The response of populations of brine shrimp to toxicants at the community level may be stronger when predation is present than the response of populations without predation pressure, as the regulation capacity of the population (measured as an increased production of offspring at reduced population densities) is exhausted when predation is present. Future ecotoxicological risk assessment schemes should consider relevant community characteristics such as predation as part of an environmental risk assessment. | 18,784,796 |
Molecular beacons in biomedical detection and clinical diagnosis. | Among the diverse nucleic acid probes, molecular beacons (MBs) have shown their excellent potential in a variety of basic researches and practical applications. Their excellent selectivity, sensitivity, and detection without separation have led them to be particularly useful in real-time intracellular monitoring of gene expression, development of biosensors, and clinical diagnostics. This paper will focus on the properties of various MBs and discuss their potential applications. | 18,784,800 |
Prognostic significance of flow cytometric immunophenotyping in acute myeloid leukemia. | The prognostic significance of flow cytometric immunophenotyping (FCI) in acute myeloid leukemia (AML) has been controversial. In this study, we re-investigated the possible role of FCI in the prediction of AML relapse following standard chemotherapy. A total of 209 AML cases with follow-up information were analyzed. Among those, 78 cases were in remission (M:F=44/34; mean age of 48.9 years) and 131 had relapse (M:F=71/60; mean age of 51.3 years). The expression of CD34, HLA-DR or a combination of both was significantly different between the remission and relapse groups for all AML as well as AML without t(15;17). None of the pammyeloid markers or their combinations analyzed was found to correlate with treatment outcomes. Complex cytogenetic abnormalities were more likely associated with relapse group than with remission group, but were not statistically significant after excluding AML with t(15;17). In conclusion, FCI is useful in predicting treatment outcome and disease relapse in AML. | 18,784,805 |
HIV-1 TAT inhibits microglial phagocytosis of Abeta peptide. | Human immunodeficiency virus (HIV)-associated dementia (HAD) is a subcortical neuropsychiatric syndrome that has increased in prevalence in the era of highly active antiretroviral therapy (HAART). Several studies demonstrated increased amyloidosis in brains of HIV patients and suggested that there may be a significant number of long-term HIV survivors with co-morbid Alzheimer's disease (AD) in the future. We show HIV-1 Tat protein inhibits microglial uptake of Abeta1-42 peptide, a process that is enhanced by interferon-gamma (IFN-gamma) and rescued by the STAT1 inhibitor (-)-epigallocatechin-3-gallate (EGCG). It is hypothesized that reduced Abeta uptake occurs through IFN-gamma mediated STAT1 activation. This process promotes a switch from a phagocytic to an antigen presenting phenotype in microglia through activation of class II transactivator (CIITA). Additionally, we show that HIV-1 Tat significantly disrupts apolipoprotein-3 (Apo-E3) promoted microglial Abeta uptake. As Tat has been shown to directly interact with the low density lipoprotein (LRP) receptor and thus inhibit the uptake of its ligands including apolipoprotein E4 (Apo-E4) and Abeta peptide in neurons, we further hypothesize that a similar inhibition of LRP may occur in microglia. Future studies will be required to fully characterize the mechanisms underlying IFN-gamma enhancement of HIV-1 Tats disruption of microglial phagocytosis of Abeta and Apo-E3. | 18,784,813 |
C-MYC rearrangements are frequent in aggressive mature B-Cell lymphoma with atypical morphology. | Diagnosis and classification of aggressive mature B-cell lymphoma with atypical morphology remains a challenge. To identify factors that may contribute to the atypical morphology, we selected eight such cases and evaluated their morphologic, immunophenotypic and cytogenetic features and clinical outcomes. The neoplastic cells showed a diffuse monotonous infiltrating pattern with a spectrum of morphology including: 1) L1 lymphoblastic; 2) centroblastic; 3) immunoblastic; and 4) mixed centroblastic and immunoblastic. The lymphoma cells in most cases were positive for CD10 and/or BCL6, and showed BCL2 expression. 6 of 8 cases showed C-MYC rearrangements, and interestingly, all 6 cases demonstrated a proliferation index of < or =90%. 3 of the 6 cases also demonstrated t(14;18). Clinical follow-up indicated that aggressive mature B-cell lymphoma may benefit from more intensified chemotherapeutic regimens used for BL. Our study suggests that aggressive mature B-cell lymphoma with atypical morphology may be another "grey zone lymphoma" lying in the spectrum between Burkitt lymphoma and diffuse large B-cell lymphoma. | 18,784,824 |
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