title stringlengths 0 1.13k | abstract stringlengths 1 15.7k | PMID int64 22 36.5M |
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FcgammaRIIB signals inhibit BLyS signaling and BCR-mediated BLyS receptor up-regulation. | These studies investigate how interactions between the BCR and FcgammaRIIB affect B lymphocyte stimulator (BLyS) recep-tor expression and signaling. Previous studies showed that BCR ligation up-regulates BLyS binding capacity in mature B cells, reflecting increased BLyS receptor levels. Here we show that FcgammaRIIB coaggregation dampens BCR-induced BLyS receptor up-regulation. This cross-regulation requires BCR and FcgammaRIIB coligation, and optimal action relies on the Src-homology-2 (SH2)-containing inositol 5 phosphase-1 (SHIP1). Subsequent to FcgammaRIIB/BCR coaggregation, the survival promoting actions of BLyS are attenuated, reflecting reduced BLyS receptor signaling capacity in terms of Pim 2 maintenance, noncanonical NF-kappaB activation, and Bcl-xL levels. These findings link the negative regulatory functions of FcgammaRIIB with BLyS-mediated B-cell survival. | 18,791,164 |
Regulated expression of caspase-12 gene in human retinal pigment epithelial cells suggests its immunomodulating role. | To investigate the expression and regulation of the short form of caspase-12, caspase-12S, in human retinal pigment epithelial (hRPE) cells. hRPE cells were stimulated by the proinflammatory agents IL-1beta (2 ng/mL) and TNF-alpha (20 ng/mL); LPS (1000 ng/mL); coculture with monocytes; the immunomodulating agent cyclosporine (Cys; 30 ng/mL); the anti-inflammatory cytokine IL-10 (100 U/mL); and the endoplasmic reticulum (ER) stress inducers tunicamycin (3 or 10 muM) and thapsigargin (25 or 100 nM) for 6 hours or longer. The total RNAs were isolated and subjected to semiquantitative and quantitative real-time RT-PCR analysis. Effects of tunicamycin and thapsigargin on IL-1beta- and TNF-alpha-stimulated MCP-1 mRNA expression and protein production were further examined by RT-PCR and ELISA, respectively. RT-PCR results showed that caspase-12S is the predominant form of caspase-12 in the examined hRPE cells of this study, with expression at levels as high as those in many other human tissues such as pancreas, prostate, small intestine, lung, spleen, and kidney. Treatment with IL-1beta and TNF-alpha, as well as LPS and coculture with monocytes reduced hRPE caspase-12S mRNA expression within 6 hours. In contrast, hRPE exposure to cyclosporine (Cys) and the cytokine IL-10 for 6 hours increased caspase-12S mRNA expression. Compared to Cys and IL-10, the ER stress activators tunicamycin and thapsigargin were even more potent enhancers of hRPE caspase-12S gene expression. They also caused corresponding reductions in IL-1beta- and TNF-alpha-induced MCP-1 mRNA expression and protein production. hRPE cells express a high level of caspase-12S. The regulated expression of caspase-12S suggests that this caspase recruitment domain (CARD)-only protein may be an endogenous dominant negative regulator that modulates inflammatory responses in hRPE cells. | 18,791,174 |
Coping with chronic pain among younger, middle-aged, and older adults living with neurological injury and disease. | Objective. This article compares use of pain coping strategies among older, middle-aged, and younger adults living with chronic pain and seeks to determine whether the relationship between pain severity and coping is moderated by age. Method. Participants were 464 adults reporting chronic pain secondary to multiple sclerosis, spinal cord injury, or neuromuscular disease. Participants completed a survey including measures of pain severity and the Chronic Pain Coping Inventory. Results. After controlling for clinical and demographic variables, older adults (older than 60) reported a wider range of frequently used strategies and significantly more frequent engagement in activity pacing, seeking social support, and use of coping self-statements than did younger or middle-aged adults. Moderation analyses suggest that, for younger adults, efforts at coping generally increased with greater pain severity, whereas this relationship did not exist for older adults. Discussion. These data suggest differences in the quantity and quality of pain coping among age groups. | 18,791,184 |
A method for generating natural and user-defined sniffing patterns in anesthetized or reduced preparations. | Sniffing has long been thought to play a critical role in shaping neural responses to odorants at multiple levels of the nervous system. However, it has been difficult to systematically examine how particular parameters of sniffing behavior shape odorant-evoked activity, in large part because of the complexity of sniffing behavior and the difficulty in reproducing this behavior in an anesthetized or reduced preparation. Here we present a method for generating naturalistic sniffing patterns in such preparations. The method involves a nasal ventilator whose movement is controlled by an analog command voltage. The command signal may consist of intranasal pressure transients recorded from awake rats and mice or user-defined waveforms. This "sniff playback" device generates intranasal pressure and airflow transients in anesthetized animals that approximate those recorded from the awake animal and are reproducible across trials and across preparations. The device accurately reproduces command waveforms over an amplitude range of approximately 1 log unit and up to frequencies of approximately 12 Hz. Further, odorant-evoked neural activity imaged during sniff playback appears similar to that seen in awake animals. This method should prove useful in investigating how the parameters of odorant sampling shape neural responses in a variety of experimental settings. | 18,791,186 |
Expression of Xhdsi-1VOC, a novel member of the vicinal oxygen chelate (VOC) metalloenzyme superfamily, is up-regulated in leaves and roots during desiccation in the resurrection plant Xerophyta humilis (Bak) Dur and Schinz. | The annotation of novel plant genes is frequently based on sequence and structural similarity to known protein motifs. Understanding the biological function of these genes is dependent on identifying conditions under which they are activated, however. The resurrection plant, Xerophyta humilis is a good model system for identifying and characterizing genes which are important for desiccation tolerance. Desiccation induced-1 (dsi-1(VOC)), a previously uncharacterized plant gene, is up-regulated during desiccation in leaves, roots, and seeds in X. humilis. The X. humilis desiccation induced-1 gene, Xhdsi-1(VOC), shares structural homology with the vicinal oxygen chelate (VOC) metalloenzyme superfamily. Proteins in this superfamily share little sequence similarity, but are characterized by a common betaalphabetabetabeta structural fold. A number of plant orthologues of XhDsi-1(VOC) have been identified, including Arabidopsis thaliana At1g07645, which is currently annotated as a glyoxalase I-like gene, and many ESTs derived from seed cDNA libraries. Xhdsi-1(VOC) and its orthologues do not, however, contain the glutathione and zinc binding sites conserved in glyoxalase I genes. Furthermore, expression of Xhdsi-1(VOC) in yeast failed to rescue a yeast glyoxalase I mutant. Messenger RNA transcripts for At1g07645 accumulate during seed maturation, but are not induced by water loss, salt or mannitol stress in vegetative tissue in Arabidopsis. It is concluded that dsi-1(VOC) is a seed-specific gene in desiccation-sensitive plants that is activated by water loss in vegetative tissues in the resurrection plant X. humilis and plays an important role in allowing plant tissues to survive loss of 95% of their relative water content. | 18,791,196 |
Insulator and Ovo proteins determine the frequency and specificity of insertion of the gypsy retrotransposon in Drosophila melanogaster. | The gypsy retrovirus of Drosophila is quite unique among retroviruses in that it shows a strong preference for integration into specific sites in the genome. In particular, gypsy integrates with a frequency of > 10% into the regulatory region of the ovo gene. We have used in vivo transgenic assays to dissect the role of Ovo proteins and the gypsy insulator during the process of gypsy site-specific integration. Here we show that DNA containing binding sites for the Ovo protein is required to promote site-specific gypsy integration into the regulatory region of the ovo gene. Using a synthetic sequence, we find that Ovo binding sites alone are also sufficient to promote gypsy site-specific integration into transgenes. These results indicate that Ovo proteins can determine the specificity of gypsy insertion. In addition, we find that interactions between a gypsy provirus and the gypsy preintegration complex may also participate in the process leading to the selection of gypsy integration sites. Finally, the results suggest that the relative orientation of two integrated gypsy sequences has an important role in the enhancer-blocking activity of the gypsy insulator. | 18,791,225 |
Dominance, overdominance and epistasis condition the heterosis in two heterotic rice hybrids. | Two recombinant inbred (RI) populations having 194 and 222 lines each, derived, respectively, from a highly heterotic inter- (IJ) and intrasubspecific (II) hybrid, were backcrossed to their respective parents. The RI and two backcross populations along with F1 and its two parents of each hybrid were evaluated for nine important traits, including grain yield and eight other yield-related traits. A total of 76 quantitative trait loci (QTL) for the IJ hybrid and 41 QTL for the II hybrid were detected in the RI population, midparent heterosis of two backcross populations, and two independent sets of data by summation (L1 + L2) and by subtraction (L1 - L2) of two backcross populations (L1 and L2). The variance explained by each QTL ranged from 2.6 to 58.3%. In the IJ hybrid, 42% (32) of the QTL showed an additive effect, 32% (24) a partial-to-complete dominant effect, and 26% (20) an overdominant effect. In the II hybrid, 32% (13) of the QTL demonstrated an additive effect, 29% (12) a partial-to-complete dominant effect, and 39% (16) an overdominant effect. There were 195 digenic interactions detected in the IJ hybrid and 328 in the II hybrid. The variance explained by each digenic interaction ranged from 2.0 to 14.9%. These results suggest that the heterosis in these two hybrids is attributable to the orchestrated outcome of partial-to-complete dominance, overdominance, and epistasis. | 18,791,236 |
A novel septin-associated protein, Syp1p, is required for normal cell cycle-dependent septin cytoskeleton dynamics in yeast. | Septins are a family of GTP-binding proteins whose heterooligomeric complex is the basic structural element of the septin filaments found in many eukaryotic organisms. In budding yeast, septins are mainly confined at the mother-daughter junction and are required for cell morphogenesis and division. Septins undergo assembly and disassembly in accordance with the progression of the cell cycle. In this report, we identified the yeast protein Syp1p as a new regulator of septin dynamics. Syp1p colocalizes with septins throughout most of the cell cycle. Syp1p interacts with the septin subunit Cdc10p and can be precipitated by Cdc10p and Cdc12p. In the syp1Delta mutant, both formation of a complete septin ring at the incipient bud site and disassembly of the septin ring in later stages of cell division are significantly delayed. In addition, overexpression of Syp1p causes marked acceleration of septin disassembly. The fluorescence recovery after photobleaching (FRAP) assay further showed that Syp1p promotes septin turnover in different cell cycle stages. These results suggest that Syp1p is involved in the regulation of cell cycle-dependent dynamics of the septin cytoskeleton in yeast. | 18,791,237 |
Selective transcriptional profiling and data analysis strategies for expression quantitative trait loci mapping in outbred F2 populations. | Genetic analysis of transcriptional profiling experiments is emerging as a promising approach for unraveling genes and pathways that underlie variation of complex biological traits. However, these genetical genomics approaches are currently limited by the high cost of microarrays. We studied five different strategies to optimally select subsets of individuals for transcriptional profiling, including (1) maximizing genetic dissimilarity between selected individuals, (2) maximizing the number of recombination events in selected individuals, (3) selecting phenotypic extremes within inferred genotypes of a previously identified quantitative trait locus (QTL), (4) purely random selection, and (5) profiling animals with the highest and lowest phenotypic values within each family-gender subclass. A simulation study was conducted on the basis of a linkage map and marker genotypes were derived from data on chromosome 6 for 510 F2 animals from an existing pig resource population and on a simulated biallelic QTL with pleiotropic effects on performance and gene expression traits. Bivariate analyses were conducted for selected subset sample sizes of 80, 160, and 240 individuals under three different correlation scenarios between the two traits. The genetic dissimilarity and phenotypic extremes within genotype methods had the smallest mean square error on QTL effects and maximum sensitivity on QTL detection, thereby outperforming all other selection strategies, particularly at the smallest proportion of samples selected for gene expression profiling (80/510). | 18,791,244 |
Identification of single-nucleotide polymorphism in the progesterone receptor gene and its association with reproductive traits in rabbits. | A total of 598 F2 does from a cross between the high and low lines selected divergently for uterine capacity during 10 generations were used in a candidate gene analysis. The presence of major genes affecting the number of implanted embryos and uterine capacity has been suggested in lines divergently selected for uterine capacity. Uterine capacity is a main component of litter size. The progesterone receptor gene was tested as a candidate gene to determine whether polymorphisms explain differences in litter size and its components. Fragments of the promoter region and exons 1-8 were amplified and sequenced. One SNP was found in the promoter region, 2464G>A, three SNPs in the 5'-UTR exon 1, and a silence SNP in exon 7. The first four SNPs were segregated in two haplotypes. The allele G found in the promoter region was found in 75% of the high-line parental animals and in 29% of the low-line parental animals. The GG genotype had 0.5 kits and 0.5 implanted embryos more than the AA genotype. At 48 hr of gestation, the difference in early embryo survival and embryonic stage of development was small. However, at 72 hr of gestation, the GG genotype had 0.36 embryos more than the AA genotype and also had a more advanced embryonic stage of development, showing a lower percentage of compacted morulae and a higher percentage of blastocysts. The difference in litter size between the GG and GA genotypes was similar to the difference found between homozygote genotypes; however, differences in implanted embryos, early embryo survival, and embryo development were not detected between the GG and GA genotypes. | 18,791,246 |
Suppression of pleiotropic effects of functional cryptochrome genes by Terminal Flower 1. | TERMINAL FLOWER 1 (TFL1) encodes a protein with similarity to animal phosphatidylethanolamine-binding proteins and is required for normal trafficking to the protein storage vacuole. In Arabidopsis thaliana the tfl1 mutation produces severe developmental abnormalities. Here we show that most aspects of the tfl1 phenotype are lost in the cry1 cry2 double-mutant background lacking cryptochromes 1 and 2. The inhibition of hypocotyl growth by light is reduced in the tfl1 mutant but this effect is absent in the cry1 or cry2 mutant background. Although the promotion of flowering under long rather than short days is a key function of cryptochromes, in the tfl1 background, cryptochromes promoted flowering under short days. Thus, normal CRY control of photoperiod-dependent flowering and hypocotyl growth inhibition requires a functional TFL1 gene. | 18,791,256 |
In vitro hemorheological study on the hematocrit effect of human blood flow in a microtube. | In vitro experiments to investigate the hematocrit effect on human blood flow in microcirculation were carried out using a micro-PIV technique. The micro-PIV system consisted of a 2 head Nd:YAG laser as a illumination light, a cooled CCD camera, a delay generator and a personal computer for control and data processing. Human blood with a hematocrit of 20, 30 and 40% was supplied into a microtube of 100 microM in diameter using a syringe pump. Fluorescent particles of 1.0 microM in mean diameter were seeded in the blood flow as tracers to measure instantaneous velocity fields by applying a cross-correlation PIV algorithm. The mean velocity field information was obtained by ensemble averaging the instantaneous velocity field data obtained. The hemorheological characteristics related with the blood flow in the microtube were also evaluated as functions of flow rate and hematocrit using the PIV data. The blood flow has a cell-free layer near the tube wall and this layer's thickness is increased with the increasing flow speed due to the radial migration. As the hematocrit increases, the velocity profile starts acquiring non-Newtonian features under low flow rate conditions. The hemorheolgical characteristics were found to influence largely on the viscosity and shear rate of blood flow. | 18,791,264 |
Comparison of the adjuvanticity of aluminum salts and their combination in hepatitis B recombinant protein vaccine in assessed mice. | Several adjuvants have been evaluated for vaccine formulations but aluminum salts will continue to be used for many years due to their safety, low cost and adjuvanticity with different antigens. Two commonly used aluminum adjuvants, aluminum hydroxide and aluminum phosphate have different adjuvanticity properties. Commercial recombinant protein hepatitis B vaccines containing aluminum hydroxide is facing low induction of immunity in some sections of the vaccinated population. In this study, to follow the current global efforts in finding more potent hepatitis B vaccine formulations, adjuvanticity of aluminum phosphate, aluminum hydroxide and their combinations has been evaluated. The formulated vaccines were administered intra-peritoneally (i.p.) to BALB/c mice and the titer of antibody was determined after 28 days using ELISA technique. The geometric mean of antibody titer (GMT, mIU/ml), seroconversion and seroprotection rates, ED50 (ng) and relative potency (microg/dose) of different formulations were determined. GMT of antibody titer, seroconversion and seroprotection rates showed significantly higher adjuvanticity for aluminum phosphate than other formulations. The ED50 of aluminum phosphate was approximately two fold less than other formulations. Aluminum phosphate showed more adjuvanticity than aluminum hydroxide and their combinations in hepatitis B protein vaccine. The use of aluminum phosphate as adjuvant leads to higher immunity which may result in more protective response in vaccinated groups. | 18,791,283 |
Hamstring injuries in sprinting - the role of eccentric exercise. | This paper assesses a specific connective tissue insufficiency induced hamstring injury occurring in the late swing/early stance phase of sprinting and jumping activities. A literature review related to hamstring injury demonstrates that eccentric muscle action is capable of producing very high forces within the series elastic component (SEC) of the hamstrings in this phase of sprinting. These high forces have been shown to be related to hamstring injury. The utilization of eccentric exercise training regimens can prevent this injury by strengthening the SEC, resulting in a musculotendinous structure theoretically capable of both generating and withstanding higher eccentric and concentric forces.A clinical approach utilizing an eccentric exercise regimen designed to strengthen the hamstrings in the late swing/early stance phase is outlined. A pilot study investigating the exercise indicates it is a valid method of preventing and rehabilitating the hamstring injury in terms of the positions at risk while sprinting, the angular velocities achieved, and the torques produced. J Orthop Sports Phys Ther 1989;10(9):343-349. | 18,791,318 |
Nutrition knowledge of sports physical therapists. | This descriptive study determined the nutrition knowledge of sports physical therapists. A Nutrition Knowledge Test was designed and mailed to 1000 members of the Sports Section of the American Physical Therapy Association. The 498 therapists who returned completed questionnaires achieved an overall mean knowledge score of 71.63%. Women scored significantly better than men; therapists in the 16+ years of experience and the 50+ years age groups scored less well. While there was a positive attitude toward nutrition, no correlation was found between attitude and nutrition knowledge. Thirty percent of the therapists reported receiving nutrition education in their physical therapy program. Thirty-two percent received nutrition information through continuing education. Those therapists with continuing education achieved significantly higher knowledge scores, particularly on the sports-related questions. The results of this study indicate that the nutrition knowledge of sports physical therapists can be increased with nutrition education provided through continuing education. J Orthop Sports Phys Ther 1989;10(7):257-263. | 18,791,320 |
Biochemical markers in glucocorticoid-induced osteoporosis. | Following the introduction of corticosteroids as therapeutic agents in the 1950s, their use has been expanded so that today glucocorticoids are widely used. There are few studies in the literature directly aimed at describing the changes of bone markers following glucocorticoid administration. The interpretation of some of these investigations may be hampered by a number of confounding factors, whose influence is not always taken into consideration. In general, the effects of glucocorticoid administration are represented by a reduction in bone formation markers (particularly considering serum osteocalcin levels) and a trend to an increase or no change in bone resorption markers. The inconsistency of this last finding may be related to the time at which the observation is carried out and to the marker employed. | 18,791,348 |
Regional recurrence after negative sentinel lymph node biopsy for melanoma. | Sentinel lymph node (SLN) biopsy has shown great utility in the management of melanoma. An analysis of regional recurrence in previously mapped negative SLN basins as the first site of relapse is performed. A retrospective query of a prospective melanoma database from 1994 to 2006 identified 1287 patients who underwent successful SLN biopsy. One thousand sixty patients (82.4%) were SLN negative and 227 (17.6%) patients SLN positive. Clinical variables were examined for the impact on regional recurrence by multivariate analysis. Mean follow-up was 44.3 months (range 3-155 months). Thirty-five patients (3.3%) presented with false-negative (FN) SLN biopsy. Pathologic review of the SLNs harvested from these basins found 7 (20.0%) samples positive for metastatic melanoma. Multivariate analysis found head and neck site [hazard ratio 3.67; 95% confidence interval (CI), 1.77-7.60, P < 0.001] and tumor thickness (hazard ratio 1.16; 95% CI, 1.04-1.30, P = 0.01) to be predictive of FN SLN biopsy. The 5-year melanoma specific survival calculated from the date of the SLN biopsy was 57.6% (95%CI, 35.7-41.9) in the FN group, which was not statistically different than the SLN positive group 60.0% (95% CI, 29.6-40.1; P = 0.14). Head and neck tumor site and tumor thickness are predictors of a FN SLN biopsy. Mechanisms other than pathologic SLN sampling error may contribute to the failure of the SLN biopsy in some patients. Patients with regional recurrence after negative SLN biopsy have a similar 5-year survival compared with patients with positive SLNs. | 18,791,358 |
The effect of age on short-term outcomes after pancreatic resection: a population-based study. | To use a large population-based cohort to determine age-dependent short-term outcomes after pancreatic resection. We identified all pancreatic resections in Texas from 1999 to 2005. Patients were stratified into 4 age groups (<60, 60-69, 70-79, and 80+ years). Bivariate and multivariate analyses were performed to determine the effect of age on mortality, discharge to home versus requiring inpatient nursing care, and length of stay. Three thousand seven hundred and thirty-six patients underwent pancreatic resection. Unadjusted in-hospital mortality increased with each increasing age group from 2.4% in patients <60 to 11.4% in patients 80 years and older (P < 0.0001). Likewise, postoperative lengths of stay increased with each increasing age group (P = 0.02). Age group independently predicted the need for discharge to an inpatient nursing unit rather than home (P < 0.0001), with the odds ration (OR) increasing with each increasing age group. With each increasing age group, patients were less likely to be resected at high-volume (H-V) hospitals (>10 pancreatic resections/y). Whereas low-volume (L-V) hospitals (< or =10 pancreatic resections/y) had higher mortality rates (3.2% versus 7.3%, P < 0.0001), the difference in mortality between H- and L-V hospitals was more striking in older patients. With increasing age group, mortality increased from 3.0% to 9.5% to 11.4% to 14.7% at L-V hospitals. It increased from 2.0% to 3.5% to 4.5% to 8.7% at H-V hospitals (P < 0.0001). In the multivariate model controlling for gender, race, hospital volume, year of surgery, diagnosis, risk of mortality, severity of illness, admission status, and procedure type, older age group independently predicted increased mortality. The OR for patients 60-69 years was 2.5 (P = 0.0003), the OR for patients 70-79 years was 1.8 (P = 0.02), and the OR for patients 80+ years was 4.4 (P < 0.0001) when compared with patients <60 years. In contrast to some previous single-institution studies, we found that increased age is an independent risk factor for mortality after pancreatic resection. For all ages, mortality rates were higher at L-V hospitals, but the difference worsened significantly with increasing age. Older patients had longer lengths of stay, were less likely to be discharged home, and more likely to require care at an inpatient nursing or acute care facility at the time of discharge. | 18,791,366 |
Experience with more than 500 minimally invasive hepatic procedures. | To evaluate our experience with more than 500 minimally invasive hepatic procedures. Recent data have confirmed the safety and efficacy of minimally invasive liver surgery. Despite these reports, no programmatic approach to minimally invasive liver surgery has been proposed. We retrospectively reviewed all patients who underwent a minimally invasive procedure for the management of hepatic tumors between January 2001 and April 2008. Patients were divided into 3 groups: laparoscopy with intraoperative ultrasound and biopsy only, laparoscopic radiofrequency ablation (RFA), and minimally invasive resection. To compare the various forms of surgery, we analyzed the incidence of complications, tumor recurrence, mortality, and cost. Statistical analysis was performed using chi(2) analysis, Student t test, Kaplan-Meier survival analysis with the log-rank test, and multivariable Cox models. A total of 590 minimally invasive hepatic procedures were performed during 489 operative interventions. The representative tumor histologies were: hepatocellular carcinoma (HCC; N = 210), colorectal carcinoma (N = 40), miscellaneous liver metastases (N = 42), biliary cancer (N = 20), and benign tumors (N = 176). Thirty-five patients underwent laparoscopic ultrasound and confirmatory biopsy alone; 201 patients underwent 240 laparoscopic RFAs, and 253 patients underwent 306 minimally invasive resections. Conversion rates to open surgery for the RFA and resection group were 2% overall. One hundred ninety-nine (40.6%) patients were cirrhotic; 31 resections were performed in cirrhotic patients. Complication and mortality rates for RFA and resection were comparable (11% vs. 16%, and 1.5% vs. 1.6%). However, complication rates (14% vs. 29%; P = 0.02) and mortality (0.3% vs. 9.7%; P = 0.006) rates were higher in the cirrhotic versus noncirrhotic resection group. Overall recurrence rates for RFA and resection groups were 24% and 23%, respectively. Local recurrence rates were higher in the RFA group (6.3% versus 1.5%; P < 0.06). Overall patient survival differed between HCC patients receiving RFA alone and those receiving RFA and OLT (P < 0.0001). Overall survival for cancer patients receiving RFA versus resection differed significantly when unadjusted for other covariates (P = 0.01), and remained marginally significant in a multivariable model (P = 0.056). Minimally invasive hepatic surgery has become a viable alternative to open hepatic surgery. Our present data are equivalent or superior to those encountered in any large open series. Our experience with RFA confirms a low local recurrence rate and an excellent technique for bridging patients to transplantation. Morbidity and mortality rates for minimally invasive hepatic resections in cirrhotics, is similar to other reported open resection series. This series confirmed excellent interim survival rates after laparoscopic HR and superiority over RFA in the treatment of cancer, with significantly lower local tumor recurrence rate. | 18,791,368 |
A third study on predicting NCLEX success with the HESI exit exam. | This was the third annual validity study designed to assess the accuracy of the HESI Exit Exam (E) in predicting NCLEX success for graduating registered and practical nursing students. As in year I (N = 2,725) and year II (N = 3,752), in year III (N = 6,277), the E was highly predictive of NCLEX success for associate degree nursing, bachelor of science nursing, diploma, and practical nursing students. Unlike previous years, in year III, monitoring was not a significant factor in the predictive accuracy of the E. NCLEX success of low-scoring E students, first examined in year II, was also examined in year III. As in year II, low-scoring E students were significantly more (P = .001) likely to fail the licensure examination than high-scoring E students. In year III, unlike year II, there was no significant difference in the pass rate of low-scoring E students who participated in a remediation program and those who did not. The authors recommended that a more definitive definition of remediation be used in future studies and that such studies focus on E implementation strategies and their relationship to NCLEX success. | 18,791,386 |
Predicting NCLEX success with the HESI Exit Exam: fourth annual validity study. | The fourth annual validity study of the Health Education Systems, Inc. (HESI) Exit Exam was designed to examine not only the accuracy of the examination in predicting NCLEX success but also the degree of risk for failure of the licensure examination associated with specific scoring intervals. A descriptive comparative design was used to examine the data provided by schools of nursing regarding students' NCLEX outcomes in the 1999-2000 academic year. As in the 3 previous studies, the examination was found to be a highly accurate predictor of NCLEX success (98.46%). Each scoring interval was significantly different from each of the other scoring intervals (P = .001). In fact, for the combined group of registered nurse and practical nurse students, the percentage of students who failed the NCLEX more than doubled with each successively lower scoring interval. These findings provide the information faculties needed to make evidence-based decisions regarding students' risks for NCLEX failure. Additionally, frequency data were obtained from this survey regarding the use of the examination as a benchmark for progression and remediation, and these findings may also be useful to faculties that are considering establishing such programs. | 18,791,387 |
Designing and delivering effective online nursing courses with the evolve electronic classroom. | This case study describes how the Evolve electronic course management system was used to deliver an online Trends and Issues in Nursing course for 53 nurses-in-training at Our Lady of Lourdes School of Nursing. Evolve provided an open-ended, electronic course shell that supported the instructor's efforts to create an online learning environment using the seven principles of effective teaching. The course was evaluated with items from the Student Evaluation of Online Teaching Effectiveness and questions written to assess unique features of the Trends and Issues course. Results indicated that most learners perceived that the course was generally a positive learning experience and that constructivist-based principles were used to design and deliver instruction that effectively promoted student learning. | 18,791,392 |
Critical pathway for the management of acute heart failure at the Veterans Affairs San Diego Healthcare System: transforming performance measures into cardiac care. | Acute decompensated heart failure (ADHF) is a major public health problem and leading cause for hospitalization in people 65 years and older. Admission rates for ADHF, accounted for more than 1 million heart failure (HF) hospitalizations in 2004, and more than 6.5 million inpatient hospital days. Despite significant advances in HF management, including pharmacotherapy and devices; and extensive collaborative efforts of the American College of Cardiology, and American Heart Association to disseminate evidence-based practice guidelines for management of chronic HF in adults; 3 patients continue to present to the emergency departments in ADHF. The hospital treatment of HF frequently does not follow published guidelines, potentially contributing to the high morbidity, mortality, and economic cost of this disorder. This highlights an ongoing need for development of quality improvement programs that focus on delivering reliable, evidence-based care for patients with ADHF. Consequently, the development of clinical pathways has the potential to reduce the current variability in care, enhance guideline adherence, and improve outcomes for patients. The Veterans Affairs San Diego Healthcare System (VASDHCS) formed a multidisciplinary HF performance improvement team. The team set forth on the task of developing standard order sets for patients with ADHF. After analyzing local care processes, reviewing evidence of best care practices, and defining appropriate goals to satisfy the multidimensional needs of HF patient; the team developed a computerized pathway in a user-friendly format that is simple, yet comprehensive; and focuses on early stages of HF evaluation and treatment for patients presenting to the emergency department. Successful strategies to improve care for HF patients need to assist health care providers with rapid recognition and early aggressive treatment, while creating a reliable process that ensures continuity of care. This critical pathway for management of acute HF at the VASDHCS provides computerized order sets that guide health care providers through accepted treatment regimens, providing documentation of treatment and assists with compliance data collection. The quality of the care is assessed by monitoring the nationally established performance measures for HF. Through the use of the HF computerized order sets, the VASDHCS currently achieves a performance level above most Joint Commission accredited organizations and in many areas achieves the best possible results compared with the top 10% of hospitals in the nation. | 18,791,404 |
Nursing program assessment and evaluation: evidence-based decision making improves outcomes. | The authors explore how an evidence-based decision-making process improved National Council Licensure Examination passing rates for a bachelor of science in nursing program. The process is one that may be applicable to other nursing programs despite differences in school mission, philosophy, and student population. The essential components of a nursing program that contribute to student success are examined. Lessons learned and opportunities for more comprehensive pertinent assessment methods are discussed. | 18,791,402 |
Diffusion tensor imaging of the kidney with parallel imaging: initial clinical experience. | To evaluate the clinical feasibility of diffusion tensor imaging (DTI) of the kidney in volunteers and patients with renal diseases. Ten volunteers and 22 patients (mean age, 56 +/- 14.3) with renal masses and renal artery stenosis underwent breath-hold coronal fat-saturated echo-planar DTI (as provided by the manufacturer, 6 diffusion directions, diffusion weightings b = 0 and 300 s/mm2, repetition time 730 ms/echo time 72 ms; 5 slices; slice thickness, 6 mm; inplane resolution, 2.1 x 2.1 mm2; acquisition time, 26 seconds) of the kidneys at 1.5 T (MAGNETOM Avanto, Siemens Medical Solutions, Erlangen, Germany). The parallel imaging technique, generalized autocalibrating partially parallel acquisitions with an acceleration factor 2, was applied. Using the commercially available Syngo DTI task card software, regions of interests were placed in the cortex, medulla, and in renal masses if present. Fractional anisotropy (FA) and apparent diffusion coefficients (ADC) were determined, and tractography was used to visualize the renal diffusion properties. Statistical analysis was performed using the Wilcoxon signed-rank sum test and paired t tests. In all volunteers, FA was significantly (P < 0.01) higher in the medulla (0.36 +/- 0.03) than in the cortex (0.21 +/- 0.02), whereas the ADC was significantly (P < 0.01) higher in the cortex (2.43 +/- 0.19) than in the medulla (2.16 +/- 0.22). Tractography typically revealed a radial preferred direction of medullary diffusion basically reflecting medullary flow.FA/ADC of simple renal cysts (n = 8) was 0.14 +/- 0.05/2.86 +/- 0.15. Renal cell carcinoma (n = 10) showed a wide FA range from 0.11 to 0.56. Using tractography, the structural organization of renal cell carcinoma such as pseudocapsules could be visualized.In 1 patient with unilateral high-grade renal artery stenosis, the cortical ADC of the affected kidney was lower than on the contralateral side (1.77/2.27) and the FA was increased (0.33/0.18). The FA of the medulla was increased (0.70/0.41) and the ADC decreased (1.43/1.90). Using parallel imaging, DTI measurements of the kidneys are feasible within a single breath-hold with good discrimination between cortex and medulla. Parallel imaging allows more slices and a superior resolution. DTI measurements of the kidney allows visualization of medullary flow, in pathology ADC and FA were altered. Further investigations will be required to evaluate the role of DTI for studying and monitoring renal ultrastructure. | 18,791,409 |
Evaluation of ovarian tumors by proton magnetic resonance spectroscopy at three Tesla. | The purpose of this study was to determine the feasibility of acquiring in vivo proton magnetic resonance spectroscopy of ovarian lesions at a magnetic field strength of 3 Tesla (T). The goal was to provide potentially diagnostic biochemical information that may aid in the characterization of ovarian neoplasms detected during clinical magnetic resonance imaging scanning. Fourteen patients referred to 2 gynecologic oncologic surgeons were examined in a whole-body 3.0 T clinical scanner using an 8-element phased-array surface coil. Single voxel spectroscopy (SVS) was undertaken after identification of lesions on T1-weighted and T2-weighted imaging. SVS was performed using the point resolved spectroscopy (PRESS) localization technique using a echo time (TE) of 135 milliseconds and repetition time (TR) of 2000 milliseconds and with 192 signal averages. Resonance integrals for the prominent signals from choline-containing compounds and creatine (Cr) were studied and presence of other prominent spectroscopic signals reported. Each SVS acquisition was performed in less than 8 minutes. Magnetic resonance spectral findings were correlated with the detailed pathology reports obtained after resection of each tumor. Pathology revealed 7 patients with malignant surface epithelial-stromal tumors, 3 patients with germ cell tumors, 3 patients with benign serous cystadenomas, and 1 patient with a non-neoplastic endometrioma. Spectroscopic data were acquired from 16 voxels in 14 patients. Resonances attributable to choline-containing compounds and Cr were recorded in all malignant tumors and some of the benign tumors. When detected, a choline/Cr integral ratio of greater than 3 was found to indicate that a tumor was malignant in nature, whereas a choline/Cr integral ratio less than 1.5 was found to indicate that a tumor was benign in nature. There was 1 exception, a 13-cm serous cystadenofibroma, where the choline/Cr integral ratio was 3.13. Several other prominent metabolites were recorded including lactate, lipid, and an as yet unassigned resonance (possibly N-acetylaspartate or sialic acid) at 2.07 ppm. Spectroscopy of ovarian masses can be recorded at 3.0 T with acceptable spectral quality and good signal-to-noise ratio. There are stringent technical considerations to be considered in obtaining good spectral quality. Further experience with a larger and more biologically variable range of tumors needs to be undertaken to determine the final clinical utility of this technique, but initial results from this small cohort are promising. | 18,791,417 |
Left lateral segmentectomy for pediatric live-donor liver transplantation: special attention to segment IV complications. | During left lateral segmentectomy for live-donor liver transplant, the vascular inflow to segment IV can be compromised. An area of ischemia can be seen intraoperatively and further segment IV resection may be needed to prevent necrosis and abscess formation. From July 1995 to February 2007, 324 consecutive living donor liver transplantations were performed at Hospital A. C. Camargo and Hospital Sirio-Libanes, Sao Paulo, Brazil. Two hundred eleven left lateral segments were transplanted in this period. Data on 204 left lateral segments donors were available for this analysis. There were 108 female and 96 male donors. Median age was 29 years (range, 16-48 years). Median follow-up time was 2.2 years (range, 2 months-11.8 years). Median intensive care unit stay was 1 day (range, 1-3 days), and median hospital stay was 5 days (range, 4-47 days). Postoperative complications were encountered in 39 donors (19.1%). Partial segment IV resection on the course of the primary surgery due to parenchyma discoloration was required in 107 cases (52.5%). Ten patients (4.9%) developed segment IV necrosis or abscesses, although four of them had had segment IVB resection intraoperatively. Segment IV necrosis or abscess significantly increased hospital stay and the number of readmissions, from 5.5+/-3.5 days to 8.4+/-3.7 days (P=0.012) and from 6 of 194 (3%) to 5 of 10 (50%) (P=0.001), respectively. Middle hepatic segment abscess or necrosis was the most frequent complication after left lateral segmentectomy (4.9%). Objective intraoperative strategies need to be developed to evaluate middle hepatic segment ischemia to identify and treat patients at higher risk. | 18,791,451 |
Atorvastatin down-regulates the primate cellular response to porcine aortic endothelial cells in vitro. | Using mixed lymphocyte reaction (MLR), the effect of atorvastatin on proliferation of human and baboon peripheral blood mononuclear cells (PBMCs) and human CD4+ T cells in response to wild-type (WT) and alpha-1,3-galactosyltransferase gene-knockout (GTKO) porcine aortic endothelial cells (pAECs) was investigated. swine leukocyte antigen class-II (SLA II) expression on pAEC before and after porcine interferon gamma (pIFN-gamma) stimulation, and the effect of atorvastatin on this expression was assessed. Added to the MLR, atorvastatin reduced (i) the human PBMC response to unstimulated (P<0.05) and (ii) the human and baboon PBMC responses to stimulated (P<0.05) WT and GTKO pAEC. Atorvastatin treatment of human PBMC before MLR reduced their response to stimulated WT (P<0.05) and GTKO (P<0.05) pAEC. Stimulation of pAEC with pIFN-gamma increased SLA II expression 20- to 60-fold, which was down-regulated by atorvastatin. Atorvastatin treatment of stimulated pAEC before MLR reduced proliferation of human PBMC (P<0.05) and CD4+ T cells (P<0.05). Atorvastatin down-regulates the primate cellular xenoresponse, possibly through its antiproliferative effect on PBMCs and the reduction of SLA II on pAECs. | 18,791,456 |
Evaluation of thalamocortical impulse propagation in the akinetic Rigd type of Parkinson's disease using high-frequency (600 Hz) SEP oscillations. | Human median nerve somatosensory evoked potentials exhibit low-amplitude, high-frequency (600 Hz) oscillations (HFOs) superimposed onto the primary cortical response 'N20.' Previous EEG-studies indicated the HFOs to reflect in part activity generated at the thalamus and within the thalamocortical radiation. Expecting impairment of thalamocortical impulse propagation in Parkinson's disease (PD) the present study aimed to explore the performance of the HFOs in a cohort of PD patients in comparison to an exactly age- and sex-matched group of controls. To avoid motor interference and to minimize the influence of central tremor oscillators to the HFOs we selected PD patients suffering from an akinetic rigid type of the disease. We recorded multichannel somatosensory evoked potentials and applied an advanced analysis combining source and time frequency analysis. Low frequency and HFO signals showed no significant differences between PD patients and the control group, neither in the source waveforms evaluation nor in the time frequency analysis. Contrasting two former studies indicating enhanced HFOs in nonselected PD patients the present results differ most probably due to the lack of motor interference effects and the missing impact of central tremor-oscillators on the signals by selecting patients without tremor. Sensory systems. Somatosensory cortex and thalamocortical relationships. | 18,791,468 |
Pneumococcal purpura fulminans successfully treated with activated protein C. | Evidence suggests that sepsis is a systemic inflammatory condition complicated by dysequilibrium in coagulation and fibrinolytic homeostasis, with a shift in the balance towards increased coagulation over fibrinolysis. Protein C is a natural anticoagulant consumed and inactivated during sepsis. We present the case of a 33-year-old female, postsplenectomy, with pneumococcal sepsis and purpura fulminans, successfully treated with activated protein C. | 18,791,506 |
Anemia following Roux-en-Y surgery for morbid obesity: a review. | Morbid obesity is a significant problem in the Western world. Recently, there has been an increase in the number of patients undergoing surgical weight loss procedures. Currently, the most widely performed procedure is the Roux-en-Y gastric bypass operation which combines restriction of food intake with malabsorption of calories and various nutrients, resulting in weight loss and nutritional deficiencies, respectively. Various types of anemia may complicate Roux-en-Y and commonly include deficiencies of iron, folate, and vitamin B12. Iron deficiency is particularly common and may result from many mechanisms including poor intake, malabsorption, and mucosal bleeding from marginal ulceration. However, less appreciated etiologies of nutritional anemia include deficiencies of B-complex vitamins, ascorbic acid, and copper. Replacement of the missing or decreased constituent usually reverses the anemia. Since physicians of various medical and surgical specialties are often involved with the postoperative care of bariatric patients, a review of anemia in this patient population is warranted. | 18,791,538 |
Determinants of cataract surgical opportunities and complication rates in UK higher specialist training. | The volume of cataract surgery performed by trainee ophthalmologists in the UK, and the complication rates experienced by those trainees is unknown. As a result, no appropriate audit benchmark exists for trainees or their trainers. This study describes the surgical opportunities and rates of posterior capsule rupture (PCR) experienced by higher specialist trainees in one UK training region and explores influencing factors. Number of cataract operations and episodes of PCR in each calendar month were recorded from surgical logbooks for all Specialist Registrars (SpRs) who had completed at least 6 months of training by January 2007. Dates and details of the posts in which the surgery was performed were also recorded. Data from 475 completed months were collected from 19 trainees including 4322 cataract operations and 99 episodes of PCR. Trainees performed a mean 9.1 operations per month. This varied significantly between different subspeciality posts; the fewest cataracts were on paediatric and oculo-plastic firms. District General Hospitals offered more surgery than Teaching Hospitals; mean 10.9 vs 8.5 cataracts per month (P=0.005). No difference in surgical opportunity was found between male and female trainees. An overall PCR rate of 2.3% (95% CI 2.25-2.33%) was found, which decreased significantly with increasing experience (P<0.01). SpRs in Yorkshire expect to complete around 500 cataract operations in their 4.5 years of training. A PCR rate of 2.3% was found for trainees with a mean of 25 months higher specialist training which compares favourably with published series of trainees from other countries. | 18,791,546 |
Retinal microstructure in patients with EFEMP1 retinal dystrophy evaluated by Fourier domain OCT. | To investigate retinal microstructure of patients affected with malattia leventinese (MLVT) and mutation in the EFEMP1 gene using high-resolution optical coherence tomography (OCT). Patients diagnosed with MLVT received a comprehensive eye exam, full-field and multifocal electroretinogram testing and imaging with a high-resolution Fourier domain OCT (Fd-OCT, UC Davis Medical Center, Davis, USA; axial resolution: 4.5 microm, acquisition speed: 9 frames s(-1), 1000 A scans s(-1)) combined with a flexible scanning head (Bioptigen Inc. Durham, NC, USA). Two related patients aged 30 and 60 years, with MLVT and identified c.R345W mutation in the EFEMP1 gene, were tested. Mother and daughter showed a variable phenotype with reduced vision function in the younger patient, whereas the mother had a 'form frustre'. Fd-OCT revealed extensive or focal sub-retinal pigment epithelium (RPE) deposits, separation of RPE and Bruch's membrane, and disruption of the photoreceptor outer and inner segment layers. No outer retinal changes were visible outside areas with sub-RPE deposits. Retinal structure in EFEMP1 retinal dystrophy is reflected by morphological changes within the RPE/Bruch's membrane complex with accumulation of sub-RPE material associated with disrupted photoreceptor integrity. The pattern of microstructural retinal abnormalities is similar but with a different extent in patients with variable phenotypes. | 18,791,549 |
Pain perception during inferior alveolar injection administered with the Wand or conventional syringe. | This study compared a computerised device (the Wand) with a conventional syringe in terms of the pain of needle insertion and injection during inferior alveolar nerve (IAN) block injection. The subjects were 40 patients between the ages of 18 and 30 years requiring local anaesthesia for dental restoration in the mandible. Before anaesthetic administration, the patients' anxiety levels were determined. Contralateral IAN injections were administrated at two separate appointments with random use of either the Wand or a conventional syringe. Following the injection, the patients used both the pain rating score (PRS) and a visual analogue scale (VAS) to assess the intensity of pain. When pain was measured after the injection, the Wand was found to be less painful than the syringe for the pain of both needle insertion and injection (p <0.05). The Wand technique resulted in significantly lower pain scores during the IAN block injections. Most of the patients preferred the IAN injection with the Wand for future dental injections. | 18,791,585 |
Unusual complications of the subcutaneous port catheter. | Several complications following both implantation and long-term usage of port catheters have been documented in many reports. With this article, we want to report two rare complications of the port-a-cath. Retrospective chart analysis was performed on 178 patients, who received a subcutaneous port catheter between 2002 and 2007. Patients who developed complications that were not common in the literature were selected. During removal of the catheters, two appeared to be fractured at the level of the clavicle and the first rib. The two patients with split catheters were radiologically examined in the operation theatre to locate the distal part of the catheter. One of them was located in the inferior vena cava and the other in the sinus coronarius. Both catheter tips were removed with a snare under angiographic guidance. Another port catheter was removed due to malfunction and appeared to be deformed, probably due to improper usage of the port needles. The final position of the port catheter should be radiologically verified before removal, with assistance of an interventional radiologist if necessary. The removed ports should be examined for any possible deformities and the oncology nurses should be instructed on how to use and take care of the port catheters. | 18,791,623 |
Preparation and properties of a novel drug delivery system with both magnetic and biomolecular targeting. | By loading doxorubicin (DOX) on 5-carboxyl-fluorescein (FAM) labeled AGKGTPSLETTP peptide (A54) coupled starch-coated iron oxide nanoparticles (SIONs), we prepared a novel aqueous drug delivery system with both magnetic and biomolecular targeting, which was specific to human hepatocellular carcinoma cell line BEL-7402. The saturated extent of adsorption reached 2.0 mg DOX/mg A54-SIONs at 28 degrees C, which provided a rather high dose of DOX loading for application. Tests in vitro demonstrated the specificity of DOX-loaded A54-SIONs to BEL-7402 cells. The microscopy images proved that DOX-loaded A54-SIONs were successfully targeted to tumor tissue of nude mice with an external magnetic field in vivo. MTT assay showed higher cytostatic effect of DOX-loaded A54-SIONs to hepatocellular carcinoma cells BEL-7402 than that of DOX-loaded SIONs. | 18,791,664 |
Transthoracic Collis-Nissen repair for massive type IV paraesophageal hernia. | An 80-year-old woman presented with type IV massive hiatal hernia with intrathoracic upside-down stomach and transverse colon. She was dyspneic and vomited upon consuming food or water. Consequently, she developed aspiration pneumonia. Both esophagoscopy and upper gastrointestinal series demonstrated significant cephalad displacement of the gastroesophageal junction. A Collis-Nissen hernial repair by muscle-sparing mini-thoracotomy was performed successfully. To date, 3 years after surgery, the patient is enjoying normal oral intake, has an excellent activities of daily living level, and there is no hernia recurrence. Cases of massive paraesophageal hernia are frequently associated with esophageal shortening that causes tension on the repairs and late failure. Advantages of the transthoracic approach in such cases include feasibility of direct esophageal mobilization, accurate assessment of esophageal tension, and facilitation of Collis gastroplasty. The true indication for transthoracic Collis-Nissen repair among cases of paraesophageal hiatal hernia with a short esophagus should be acknowledged more in the era of laparoscopy. | 18,791,669 |
Hybrid myocardial revascularization complicated by delayed anastomotic bleeding. | We present a case of hybrid coronary revascularization complicated by delayed bleeding from an anastomotic site. Anastomosis of the left internal mammary artery to the left anterior descending coronary artery was successfully performed via a lateral anterior small thoracotomy. Scheduled subsequent percutaneous coronary intervention of residual stenoses was successfully performed 13 days after the surgery, but cardiac tamponade due to anastomotic site dehiscence was disclosed soon after the percutaneous procedure. We discuss the causation of the delayed bleeding that occurred after the hybrid coronary revascularization. | 18,791,671 |
Glyceraldehyde-derived advanced glycation end products (AGEs). A novel biomarker of postprandial hyperglycaemia in diabetic rats. | There is a growing body of evidence that postprandial hyperglycaemia plays an important role in accelerated atherosclerosis and may be a therapeutic target for preventing cardiovascular disease (CVD) in diabetes. However, there is no convenient biomarker that could reflect cumulative postprandial hyperglycaemia in diabetes. We have recently found that glyceraldehyde can rapidly react with amino groups of proteins to form glyceraldehyde-derived advanced glycation end products (AGEs), which evoke vascular inflammation and endothelial dysfunction, thereby being implicated in accelerated atherosclerosis in diabetes. In this study, we examined whether glyceraldehyde-derived AGEs were a biomarker that could reflect cumulative postprandial hyperglycaemia in Goto-Kakizaki (GK) rats fed twice a day. GK rats at 8 weeks of age were divided into 2 groups; either the vehicle (VEH) or 50 mg/kg of nateglinide (NAT) was administered twice daily just before each meal. After 6 weeks, nateglinide treatment was found to not only prevent postprandial hyperglycaemia, but also reduce glyceraldehyde-derived AGE levels in GK rats fed twice a day. However, there was no significant difference in HbA1c or glucose-derived AGE levels between the two groups. The present study demonstrated for the first time that glyceraldehyde-derived AGEs, but not HbA1c or glucose-derived AGEs, were a biomarker that could reflect cumulative postprandial hyperglycaemia in diabetic rats. Glyceraldehyde-derived AGEs may be a novel therapeutic target for preventing CVD in diabetes. | 18,791,692 |
In vitro nonenzymatic glycation of guanosine 5'-triphosphate by dihydroxyacetone phosphate. | Dihydroxyacetone phosphate (DHAP) is a glycolytic intermediate that has been found to be significantly elevated in the erythrocytes of diabetic patients and patients with triosephosphate isomerase deficiency. DHAP spontaneously breaks down to methylglyoxal, a potent glycating agent that reacts with proteins and nucleic acids in vivo to form advanced glycation endproducts (AGEs). Like methylglyoxal, DHAP itself is also a glycating metabolite, capable of condensing with proteins and altering their structure or function. The objective of this investigation was to evaluate the susceptibility of nucleotides to nonenzymatic attack by DHAP, and to determine the factors influencing the rate and extent of nucleotide glycation by this sugar. Of the four nucleotide triphosphates (ATP, CTP, GTP and UTP) that were studied, only GTP was reactive, forming a wide range of UV and fluorescent products with DHAP. Increases in temperature and nucleotide concentration enhanced the rate and extent of GTP glycation by DHAP and promoted the heterogeneity of AGEs. Capillary electrophoresis, HPLC, and mass spectrometry allowed for a thorough analysis of the glycated products and demonstrated that the reaction of DHAP with GTP occurred via the classical Amadori pathway. | 18,791,706 |
New available SCAR markers: potentially useful in distinguishing a commercial strain of the superior type from other strains of Lentinula edodes in China. | At present, more than 100 strains of Lentinula edodes are cultivated on a commercial scale in China. A simple, reliable, and effective method to distinguish some commercial strains of the superior type from other commercial strains is very important for the Lentinula industry. In this study, 23 commercial strains of L. edodes cultivated widely in China at present were collected and analyzed with randomly amplified polymorphic DNA (RAPD) technique. Three informative dominant sequence characterized amplified region (SCAR) markers were developed by designing three pairs of specific SCAR primers from three sequenced differential RAPD bands, respectively. Based on the three SCAR markers, three different multiplex polymerase chain reaction (PCR) phenotypes were detected among the 23 studied commercial strains and in which a multilocus phenotype characterizing a commercial strain Cr02 of the superior type could potentially be used to distinguish this strain from the other 22 studied commercial strains. To our knowledge, this study is the first to describe the development of a multiplex PCR technique based on SCAR markers for detecting the molecular phenotypes among commercial strains of L. edodes in China. | 18,791,710 |
Laparoscopic and conventional appendicectomy in children: outcomes in English hospitals between 1996 and 2006. | Laparoscopic appendicectomy is increasingly used in children. This national retrospective study compared outcomes of paediatric open and laparoscopic appendicectomy. Length of stay, readmission rates and mortality in children undergoing open and laparoscopic appendicectomy in English NHS Trusts between 1 April 1996 and 31 March 2006 were compared. Procedures coded as emergency excision of appendix (OPCS-4 H01) on the Hospital Episode Statistics (HES) database in patients less than 15 years of age were included. Multivariate analysis was used to identify independent predictors of length of hospital stay and mortality. Eighty-nine thousand, four-hundred and ninety-seven (89,497) appendicectomies were studied; of which, 2,689 (3%) were performed laparoscopically. The percentage of laparoscopic cases rose from 0.6 to 8.4% between 1996 and 2006 (Pearson's r = 0.954, P < 0.001). Length of stay (median 3, interquartile range 2 days, P = 0.068) and 28-day readmission rates were similar (6.3 vs. 7.2%, respectively; P = 0.072) between groups. No independent hospital stay advantage for laparoscopy was observed (P = 0.121). No difference in 30-day mortality (P = 0.986) or 365-day mortality (P = 0.598) was demonstrated. Hospital stay, readmission rates and mortality are similar following laparoscopic and open appendicectomy in children. | 18,791,723 |
Growth-inhibitory effect of a fucoidan from brown seaweed Undaria pinnatifida on Plasmodium parasites. | The present study was undertaken to investigate the inhibitory effects of fucoidan, a sulfated polysaccharide isolated from the edible brown seaweed Undaria pinnatifida, on the growth of Plasmodium parasites. In order to assess the anti-malarial activity of fucoidan, growth inhibition activities were evaluated using cultured Plasmodium falciparum parasites in vitro and on Plasmodium berghei-infected mice in vivo. Fucoidan significantly inhibited the invasion of erythrocytes by P. falciparum merozoites, and its 50% inhibition concentration was similar to those for the chloroquine-sensitive P. falciparum 3D7 strain and the chloroquine-resistant K1 strain. Four-day suppressive testing in P. berghei-infected mice with fucoidan resulted in a 37% suppressive effect versus the control group and a delay in death associated with anemia (P < 0.05). In addition, fucoidans had no toxic effect on RAW 264.7 cells. These findings indicate that fucoidans from the Korean brown algae U. pinnatifida inhibits the invasion of Plasmodium merozoites into erythrocytes in vitro and in vivo. | 18,791,738 |
Dynamical density functional theory for colloidal dispersions including hydrodynamic interactions. | A dynamical density functional theory (DDFT) for translational Brownian dynamics is derived which includes hydrodynamic interactions. The theory reduces to the simple Brownian DDFT proposed by Marconi and Tarazona (U. Marini Bettolo Marconi and P. Tarazona, J. Chem. Phys. 110, 8032 (1999); J. Phys.: Condens. Matter 12, A413 (2000)) when hydrodynamic interactions are neglected. The derivation is based on Smoluchowski's equation for the time evolution of the probability density with pairwise hydrodynamic interactions. The theory is applied to hard-sphere colloids in an oscillating spherical optical trap which switches periodically in time from a stable confining to an unstable potential. Rosenfeld's fundamental measure theory for the equilibrium density functional is used and hydrodynamics are incorporated on the Rotne-Prager level. The results for the time-dependent density profiles are compared to extensive Brownian dynamics simulations which are performed on the same Rotne-Prager level and excellent agreement is obtained. It is further found that hydrodynamic interactions damp and slow the dynamics of the confined colloid cluster in comparison to the same situation with neglected hydrodynamic interactions. | 18,791,754 |
Studies of membrane topology of mitochondrial cholesterol hydroxylases CYPs 27A1 and 11A1. | Mitochondrial cytochrome P450 enzymes (CYP or P450, EC 1.14.13.15) play an important role in metabolism of cholesterol. CYP27A1 hydroxylates cholesterol at position 27 and, thus, initiates cholesterol removal from many extrahepatic tissues. CYP11A1 is a steroidogenic P450 that converts cholesterol to pregnenolone, the first step in the biosynthesis of all steroid hormones. We utilized a new approach to study membrane topology of CYPs 27A1 and 11A1. This approach involves heterologous expression of membrane-bound P450 in E. coli, isolation of the P450-containing E. coli membranes, treatment of the membranes with protease, removal of the digested soluble portion and extraction of the membrane-associated peptides, which are then identified by mass spectrometry. By using this approach, we found four membrane-interacting peptides in CYP27A1, and two peptides in CYP11A1. Peptides in CYP27A1 represent a contiguous portion of the polypeptide chain (residues 210-251) corresponding to the putative F-G loop and adjacent portions of the F and G helices. Peptides in CYP11A1 are from the putative F-G loop (residues 218-225) and the C-terminal portion of the G helix (residues 238-250). This data is consistent with those obtained previously by us and others and provide new information about the membrane topology of CYPs 27A1 and 11A1. | 18,791,760 |
Femoral osteolysis around the unrevised stem during isolated acetabular revision. | Many surgeons treat progressive femoral osteolysis in association with a well-fixed stem with bone grafting but in uncontained proximal defects the graft could get into the joint, raising a question regarding whether the osteolysis can be treated by simple débridement without bone grafting. We investigated whether the curetted proximal osteolysis around an unrevised femoral component progressed in size and whether this lesion would have a deleterious effect on fixation of the femoral component in patients with isolated acetabular revision. We prospectively followed 21 patients (24 hips) who underwent acetabular revision and curetting of femoral osteolysis. The minimum followup was 3 years (mean, 4.3 years; range, 3-7.4 years). By the latest followup, no hips had major progression of the osteolytic defect through the followup period and none had any new osteolytic lesions. All hips were judged stable and to have well-fixed acetabular cups and femoral stems. Provided a femoral component is bone ingrown with osseointegration sufficient to provide long-term stability, the osteolytic defect is in the proximal aspect of the femur, and the defect is uncontained, simple curettage may preserve femoral implant stability and may prevent progression of osteolysis to another Gruen zone for at least 3 to 7 years. Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. | 18,791,773 |
Pediatric deformity correction using a multiaxial correction fixator. | Circular fixators have been used successfully to correct multiplanar deformities but are often cumbersome and may be difficult to apply. We determined whether a monolateral fixator, which allows for correction of angular deformity and displacement in three planes, can correct lower extremity deformities to within normal radiographic means (anatomic lateral distal femoral angle, anatomic medial proximal tibial angle, and tibial femoral angle). We retrospectively reviewed the clinical records and radiographs of 22 consecutive patients (25 limbs) who underwent deformity correction using a new multiaxial monolateral external fixator. The patients were 4 to 16 years of age. We had a minimum 1.2-year followup (mean, 2.14 years; range, 1.2-3.1 years). Those with primary femoral and tibial deformities had improvements in the mean deviation from normal of the anatomic lateral distal femoral angle, anatomic medial proximal tibial angle and tibial femoral angle. Patients with Blount's disease had improvements in the mean anatomic medial proximal tibial angle from 59.9 masculine to 87.8 masculine. Five patients had complications (two pin site infections, one premature consolidation, one knee flexion contracture, one recurrence of varus). Six patients developed secondary deformities, all of which were corrected using the primary or secondary hinge. We conclude this fixator can produce satisfactory results with relatively few complications. Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. | 18,791,777 |
Case report: protothecal tenosynovitis. | Protothecosis is a rare infection caused by achlorophyllic algae called Prototheca. Approximately 117 cases have been described in the literature world wide, the majority caused by the species P. wickerhamii. Cutaneous infection is the most common and cases of tenosynovitis are very rare. A local or systemic immunosuppressive factor is seen in half of the cases of protothecosis. We report a case of protothecal tenosynovitis in a middle-aged, immunocompetent woman that developed after she received sclerosing therapy of varicose veins. Administration of itraconazole with surgical débridement produced a good response. We also review the published cases of protothecal tenosynovitis. | 18,791,778 |
Amyand's hernia in premature twins. | Amyand's hernia (AH) is the presence of a normal or inflamed vermiform appendix in an inguinal hernia sac. This condition is unusual in neonates and in infants, and it has not been described in premature twins. We present two 32-day-old biovular twins with a right AH, treated with sparing of the appendix and herniotomy. The correct management of AH is discussed via a brief review of the literature. | 18,791,780 |
Plasma levels of fibroblast growth factor-23 and mineral metabolism in diabetic and non-diabetic patients on chronic hemodialysis. | Fibroblast growth factor (FGF) 23 is a circulating factor that regulates phosphate (P) metabolism. Since higher P levels are associated with vascular calcification, we examined the role of serum FGF-23 levels in P metabolism and vascular calcification in hemodialysis (HD) patients with and without diabetes mellitus (DM). Chronic HD patients with DM (n = 39) and without DM (n = 50) were enrolled. Serum samples were obtained before the start of dialysis sessions, and the FGF-23 levels were determined by enzyme-linked immunosorbent assay. Abdominal computed tomography (CT) scan was performed, and the aortic calcification index (ACI) was determined by one examiner, blinded to the patient characteristics. Measurements of bone mineral density (BMD) were performed at the time of ACI estimation. Log plasma FGF-23 levels were higher in non-DM (3.74 +/- 0.71 pg/ml) than in DM (3.35 +/- 0.74 pg/ml) patients. The log FGF-23 correlated positively with serum creatinine (r = 0.424, P < 0.0001), albumin (r = 0.225, P = 0.0337), Ca (r = 0.392, P = 0.0001), P (r = 0.735, P < 0.0001), and Ca x P product (r = 0.780, P < 0.0001). There were negative correlations between log FGF-23 and age (r = -0.208, P = 0.0497), glucose (r = -0.231, P = 0.0294), and CRP (r = -0.222, P = 0.0359). Multiple regression analyses were performed to explore the correlations between plasma FGF-23 and other factors associated with vascular calcification in all HD patients. Independent variables were selected based on the results of univariate analyses. The significant factors associated with FGF-23 in HD patients were age, serum levels of creatinine, albumin, glucose, Ca, P, and Ca x P product. Plasma FGF levels did not correlate significantly with either ACI or BMD in these patients. Our findings indicate that the plasma FGF-23 level is associated with calcium-phosphate metabolism disorders, but not with aortic calcification, in both non-DM and DM patients on chronic HD. In addition, plasma FGF-23 is associated with serum levels of creatinine and albumin. Therefore, the plasma FGF-23 level may provide a reliable marker for Ca and P imbalance and nutritional status in HD patients. | 18,791,804 |
Methanosarcina as the dominant aceticlastic methanogens during mesophilic anaerobic digestion of putrescible waste. | Taking into account isotope (13)C value a mathematical model was developed to describe the dynamics of methanogenic population during mesophilic anaerobic digestion of putrescible solid waste and waste imitating Chinese municipal solid waste. Three groups of methanogens were considered in the model including unified hydrogenotrophic methanogens and two aceticlastic methanogens Methanosaeta sp. and Methanosarcina sp. It was assumed that Methanosaeta sp. and Methanosarcina sp. are inhibited by high volatile fatty acids concentration. The total organic and inorganic carbon concentrations, methane production, methane and carbon dioxide partial pressures as well as the isotope (13)C incorporation in PSW and CMSW were used for the model calibration and validation. The model showed that in spite of the high initial biomass concentration of Methanosaeta sp. Methanosarcina sp. became the dominant aceticlastic methanogens in the system. This prediction was confirmed by FISH. It is concluded that Methanosarcina sp. forming multicellular aggregates may resist to inhibition by volatile fatty acids (VFAs) because a slow diffusion rate of the acids limits the VFA concentrations inside the Methanosarcina sp. aggregates. | 18,791,805 |
Isolation and characterization of a gene encoding cinnamate 4-hydroxylase from Parthenocissus henryana. | Cinnamate 4-hydroxylase (C4H, EC 1.14.13.11) plays an important role in the phenylpropanoid pathway, which produces many economically important secondary metabolites. A gene coding for C4H, designated as PhC4H (GenBank accession no. DQ211885) was isolated from Parthenocissus henryana. The full-length PhC4H cDNA is 1,747 bp long with a 1,518-bp open reading frame encoding a protein of 505 amino acids, a 40-bp 5' non-coding region and a 189-bp 3'-untranslated region. Secondary structure of the deduced PhC4H protein consists of 41.78% alpha helix, 15.64% extended strand and 42.57% random coil. The genomic DNA of PhC4H is 2,895 bp long and contains two introns; intron I is 205-bp and intron II is 1,172-bp (GenBank accession no. EU440734). DNA gel blot analysis revealed that there might be a single copy of PhC4H in Parthenocissus henryana genome. By using anchored PCR, a 963-bp promoter sequence was isolated and it contains many responsive elements conserved in the upstream region of PAL, C4H and 4CL including the P-, A-, L- and H-boxes. | 18,791,809 |
A pilot study of a family history risk assessment tool for cardiovascular disease. | This study evaluated the effectiveness of using a family history questionnaire to ascertain patients and families at-risk for inherited cardiovascular disease. A questionnaire composed of 21 questions was developed based on the experience of a cardiovascular genetic counselor. This questionnaire was administered to 39 patients at a University-based cardiology practice reflecting general and specialized aspects of cardiovascular medicine. Using the number and degree of relatedness of relatives reported and limited age of onset information participants were ranked into three familial risk categories. Thirty-nine patients participated in this pilot study. Of the 39 patients, six Mendelian diseases were identified. All individuals surveyed in this study were found to be at high and/or moderate risk for at least one disease based on the family history questionnaire. Twenty-five out of 39 participants (64.1%) were found to be at high risk for at least one cardiovascular disease, and thirty-three out of 39 participants (84.6%) were found to be at moderate risk for at least one disease. A family history of arrhythmia disorders, hypertension, hyperlipidemia, coronary artery disease and diabetes were more likely to be associated with a personal history in family histories of both moderate and high risk. Family history questionnaires in cardiology clinics can be a cost-effective tool for identifying patients and families who are in the greatest need of genetic evaluation and genetic counseling services. | 18,791,812 |
Gastrointestinal symptoms in a sample of children with pervasive developmental disorders. | Objective To evaluate gastrointestinal (GI) problems in a large, well-characterized sample of children with pervasive developmental disorders (PDDs). Methods One hundred seventy two children entering one of two trials conducted by the Research Units on Pediatric Psychopharmacology (RUPP) Autism Network were assessed comprehensively prior to starting treatment and classified with regard to GI symptoms. Results Thirty nine (22.7%) were positive for GI problems, primarily constipation and diarrhea. Those with GI problems were no different from subjects without GI problems in demographic characteristics, measures of adaptive functioning, or autism symptom severity. Compared to children without GI problems, those with GI problems showed greater symptom severity on measures of irritability, anxiety, and social withdrawal. Those with GI problems were also less likely to respond to treatment. | 18,791,817 |
Non-Newtonian bile flow in elastic cystic duct: one- and three-dimensional modeling. | Bile flow is thought to play an essential role in the pathophysiological genesis of cholelithiasis (gallstone formation) and in gallbladder pain. In this paper, we extend our previous study of the human biliary system (Li et al., 2007, J. Biomech. Eng., 129:164-173) to include two important factors: the non-Newtonian properties of bile, and elastic deformation of the cystic duct. A one-dimensional (1D) model is analyzed and compared with three-dimensional (3D) fluid-structure interaction simulations. It is found that non-Newtonian bile raises resistance to the flow of bile, which can be augmented significantly by the elastic deformation (collapse) of the cystic duct. We also show that the 1D model predicts the pressure drop of the cystic duct flow well for all cases considered (Newtonian or non-Newtonian flow, rigid or elastic ducts), when compared with the full 3D simulations. | 18,791,826 |
Light-harvesting complexes of vascular plants. | Light-harvesting complexes (LHCs) located in the thylakoid membrane of plant chloroplasts are the collectors of solar radiation that fuel photosynthesis, and thus enable life on our planet. They consist of pigments that are non-covalently bound to light-harvesting proteins (Lhc proteins), which form a family whose members share a significant sequence identity. Due to their central role in photosynthesis, LHCs belong in several respects to the best-analysed membrane proteins. In the past decade, tremendous progress has been made in identifying new members of the Lhc family, in localising the LHCs within the photosystems, and in elucidating the structure and function of LHCs, which is summarised in this review. By contrast, gaining insight into the assembly process and the degradation of the LHCs could not keep pace. Therefore, topics for the next decade will be the elucidation of the location(s) and the operating mode of steps in the assembly and degradation process. | 18,791,846 |
Protein assemblies with palindromic structure motifs. | Symmetric DNA sequence motifs allow the formation of palindromic protein/DNA complexes. Although symmetric protein sequence motifs are less common, recent structural discoveries have unraveled a few protein/protein complexes with palindromic symmetry. Remarkably, symmetric protein/protein complexes can be generated either by adjacent or remote sequence motifs, which may be repeated or inverted. This contribution reflects and comments on recent findings of palindromic protein/protein complexes. | 18,791,850 |
Synthesis and assessment of molecular recognizability by RP-HPLC of an N-alkyl-beta-Ala-L: -Phe-derived organic phase with self-assembling ability. | An N-alky-beta-Ala-L: -Phe derivative, N'-octadecyl-N ( alpha )-[(N-acryloyl)-beta-alanyl]-L: -phenylalanineamide (1), with a polymerizable head group has been synthesized and telomerized with the silane coupling agent 3-mercaptopropyltrimethoxysilane (MPS). SEM and DSC observations indicated that both 1 and its telomer (T-1) could self-assemble into fibrillar forms with highly ordered structures in organic media such as benzene through complementary hydrogen bonding between the amide moieties. T-1 was grafted onto porous silica gels through the terminal trimethoxysilyl group and then packed into a stainless steel column. RP-HPLC results for polycyclic aromatic hydrocarbons (PAHs) demonstrated that significantly higher molecular shape recognition could be achieved by silica-supported T-1 (Sil-T-1). In this paper, the mechanism of the selectivity enhancement in HPLC by Sil-T-1 is discussed on the basis of comparing with the corresponding L: -Phe derivative N'-octadecyl-N ( alpha )-(acryloyl)-L: -phenylalanineamide (2) without beta -Ala and the stationary phase (Sil-T-2) obtained from it. The HPLC column materials Sil-T-1 and Sil-T-2 were characterized by DSC, TGA, DRIFT-IR, and (13)C and (29)Si CP-MAS NMR spectroscopic measurements. | 18,791,858 |
Adjusted estimates for time-to-event endpoints. | In the analysis of retrospective data or when interpreting results from a single-arm phase II clinical trial relative to historical data, it is often of interest to show plots summarizing time-to-event outcomes comparing treatment groups. If the groups being compared are imbalanced with respect to factors known to influence outcome, these plots can be misleading and seemingly incompatible with results obtained from a regression model that accounts for these imbalances. We consider ways in which covariate information can be used to obtain adjusted curves for time-to-event outcomes. We first review a common model-based method and then suggest another model-based approach that is not as reliant on model assumptions. Finally, an approach that is partially model free is suggested. Each method is applied to an example from hematopoietic cell transplantation. | 18,791,867 |
Numerical modelling of foam Couette flows. | A numerical computation based on a tensorial visco-elasto-plastic model based on continuous mechanics is compared to experimental measurements on liquid foams for a bidimensional Couette flow between two glass plates, both in stationary and transient cases. The main features of the model are elasticity up to a plastic yield stress, and viscoelasticity above it. The effect of the friction of the plates is taken into account. The numerical modelling is based on a small set of standard material parameters that are fully characterised. Shear localisation as well as acute transient observations are reproduced and agree with experimental measurements. The plasticity appears to be the fundamental mechanism of the localisation of the flow. Finally, the present approach could be extended from liquid foams to similar materials such as emulsions, colloids or wet granular materials, that exhibit localisation. | 18,791,872 |
[Why not revisiting tinidazole as potential treatment of odontogenic infections?]. | Tinidazole is a 5-nitroimidazole initially introduced into clinical medicine in 1969 for the treatment of unicellular parasites. Tinidazole offers selective bactericidal activity, not influenced by the inoculum size, against anaerobic bacteria, that make it of theoretical interest against periodontopathogen infections. This article reviews the required characteristics of an antibiotic directed to odontogenic anaerobic infections, as well as the pharmacodynamic pitfalls of common antibiotic treatments. In addition the in vitro, pharmacokinetic and pharmacodynamic properties of tinidazole are reviewed, assessing the degree of its adhesion to the required characteristics, as well as identifying the gaps to be fulfilled prior to its use in this medical field. Tinidazole offers interesting characteristics making worthy investigations as a candidate for the treatment of anaerobic odontogenic infections. \ | 18,791,873 |
Early counselling and support for patients with mild Alzheimer's disease and their caregivers: a qualitative study on outcome. | The aim of this qualitative study was to identify and analyse the participants' experienced outcome of an intensive structured psychosocial intervention programme with tailored counselling, education and support groups for home-living patients with mild Alzheimer's disease and their spousal caregivers. Data were collected by semi-structured in-depth interviews conducted separately with each person in 10 couples before the intervention and 1-3 months after completed intervention. For the analysis, a template organizing style of interpretation was used. The analysis revealed that patients found support groups relevant: they found it stimulating to be with peers, it supported their self-esteem, and it supported them in finding new ways of managing everyday life and social relations. During and after the intervention, caregivers were better able to cope with the challenges their partner's disease involved, and they were able to face everyday life and social relations with more serenity and competence. After the intervention, both patients and caregivers sought suitable support groups they could join as a permanent activity and caregivers sought permanent counselling. Early tailored counselling and support may improve patients' and caregivers' opportunities to adapt to the challenges of Alzheimer's disease and to maintain well-being. | 18,791,891 |
Social integration, a sense of belonging and the Cenotaph Service: old soldiers reminisce about Remembrance. | This study explored how war commemorations such as the Cenotaph Service in the UK enable older veterans to benefit from a feeling of integration and belonging gained from both comradeship and acknowledgement from wider society. Focus groups preceded by a video clip of the Cenotaph Service with 45 veterans were used to discuss the significance of collective commemorations for older veterans. Findings indicated that social integration and a sense of belonging are fostered both by comradeship and societal support during collective commemorations allowing veterans to reminisce safely. Spontaneous reminiscences involving troubling memories may be processed more easily with the support, social integration and sense of belonging which occurs at collective commemorations. Many Korean War and female World War II veterans felt forgotten and socially isolated, but described gaining vicarious support via collective commemorations. Cohen and Wills' (1985) main-effects and buffering models of social support are used to discuss the findings further. Collective commemorations can be important sources of support for many older veterans. Both comradeship and societal support promote social integration and a sense of belonging (main-effects), which enabled reminiscing and processing (buffering) to occur. | 18,791,900 |
Exploring dendrimer towards dual drug delivery: pH responsive simultaneous drug-release kinetics. | A major problem associated with conventional leukaemia chemotherapy is the development of resistance that can be surmounted well by combination chemotherapy. The objective of the present investigation is to report a novel technology to load two anti-leukaemic drugs of choice simultaneously inside the PAMAM dendrimer. Under optimized conditions of pH and dialysis time, one molecule of PAMAM dendrimer was found to be capable of entrapping 27.02 ± 0.51 and 8.00 ± 0.46 molecules of Methotrexate and all-trans Retinoic acid (ATRA), respectively. The simultaneous in-vitro release profiling of the loaded drugs was studied at pH 4, 7.4 and 10. The release kinetics was found to be governed by degree of dendrimer protonation, with more sustained and controlled behaviour at pH 7.4. Terminal loading of dendrimer with less haemolytic bioactive (ATRA) reduced the haemolytic toxicity of the dendrimer formulation. A cytotoxicity study was performed on HeLa cell lines by MTT assay, wherein after 72 h, the dual-drug loaded dendrimer was found to be more efficient (IC(50) 0.5 µM) as compared to that of the free drug combination (IC(50) 0.75 µM). | 18,791,906 |
New operative technique for treatment of arthroscopically-confirmed injury to the scapholunate ligament by volar capsuloplasty augmented with a free tendon graft. | We report how scapholunate (SL) lesions found during arthroscopy were treated using a new palmar operation based on the use of a tendon loop formed using the palmaris longus tendon, with promising preliminary results. Scapholunate instability induced by hyperextension injury was diagnosed and graded arthroscopically. Volar capsuloplasty was then done by free tendon graft in the same session in 31 patients with grades II-IV scapholunate instability. Half of the patients operated on had a normal range of movement, and all except one had flexion-extension of at least 75% of the normal. Half of the patients had no pain or limitations of the use of the wrist, and although half the patients had some pain on exertion, not one had severe pain. These results are comparable to, or even better than, those reported using other methods of repair. The combined procedure saves money, diminishes the total recuperation time and, as autologous tissues are used for the repair, secondary operations for removal of the implant are unnecessary. This method seems to be a useful adjunct to the types of operative treatment available, although it is apparently not suitable in static grade IV SL instability. | 18,791,908 |
Dietary intake of soy protein and tofu in association with breast cancer risk based on a case-control study. | Soy food and its constituents may protect against breast cancer, but the association between soy intake and decreased breast cancer risk is inconsistent. We evaluated the relationship between breast cancer risk and the dietary intake of soy protein as measured by total soy food and tofu intake. Histologically confirmed cases (n = 362) were matched to controls by age (within 2 yr) and menopausal status. High soy protein intake was associated with reduced breast cancer risk in analyses adjusted for potential confounders including dietary factors among premenopausal women (odds ratio [OR] = 0.39 in the highest quintile, 95% confidence interval [CI] = 0.22-0.93, P for trend = 0.03) and postmenopausal women (OR = 0.22, 95% CI = 0.06-0.88, P for trend = 0.16). We also found an inverse association between total tofu intake and breast cancer risk among premenopausal women (for total tofu intake, OR = 0.23 in the highest quintile, 95% CI = 0.11-0.48, P for trend < 0.01; for at least 1 serving of tofu as the main ingredient per day, OR = 0.26, 95% CI = 0.13-0.55, P for trend < 0.01). We concluded that increased regular soy food intake at a level equivalent to traditional Korean consumption levels may be associated with a reduced risk of breast cancer, and this effect is more pronounced in premenopausal women. | 18,791,919 |
AlphaIIbG236E causes Glanzmann thrombasthenia by impairing association with beta3. | Glanzmann thrombasthenia (GT) is a recessively inherited bleeding disorder caused by the quantitative or qualitative deficiency of the platelet fibrinogen receptor, integrin alphaIIbbeta3. The N-terminal domain of the alphaIIb subunit is folded in a beta-propeller that plays the role of binding fibrinogen and associating with the ligand-binding region of beta3. Analysing the mutations of Italian GT patients we found that a patient had a alphaIIb G236E missense substitution that substitutes a glycine from the highly conserved PhiPhiGPhi motif of blade 4 of the beta-propeller. To verify experimentally the effect of the substitution of glycine 236 human embryonic kidney (HEK) cells were transfected with normal or mutated alphaIIb in conjunction with normal beta3. Using flow cytometry analysis we found the percentage of HEK cells transfected with alphaIIbG236Ebeta3 that reacted with anti alphaIIbbeta3 was very low. In HEK cells transfected with either alphaIIbbeta3 or alphaIIbG236Ebeta3 and lysed, when immunoblotting was done in non-reducing conditions a band reacting with an antibody against alphaIIb was present in both lysates, although less intense in cells transfected with alphaIIbG236Ebeta3. In reducing condition alphaIIb from cells transfected with alphaIIbbeta3 was nearly all mature, while in cells transfected with alphaIIbG236Ebeta3 the ratio pro-alphaIIb: alphaIIb was 1 : 1, with signs of degradation of the mutated protein. Cell lysates were then immunoprecipitated with antibodies against alphaIIb and immunoblotted with an antibody reacting with beta3. While in immunoblots from cells transfected with alphaIIbbeta3 a band corresponding to beta3 was strongly detectable, in immunoblots originating from cells transfected with alphaIIbG236Ebeta3 no band at the same level of normal beta3 was detected. Immunofluorescence studies showed accumulation of alphaIIbG236Ebeta3 in the endoplasmic reticulum and minimal transport to the Golgi. In conclusion we demonstrated that the alphaIIbG236E mutation causes GT by impairing the association with beta3 during biogenesis of the receptor. | 18,791,937 |
Color Doppler US evaluation of feeding artery after balloon angioplasty of the drainage vein in dysfunctional hemodialysis AVF. | The aim of this study was to investigate flow rate and resistive index (RI) parameters of the feeding artery after balloon angioplasty of the drainage vein in dysfunctional hemodialysis arteriovenous fistula (AVF) due to venous stenosis/thrombosis. A cohort of 10 patients with native dysfunctional hemodialysis AVF was evaluated prospectively. Three of the 10 patients had a thrombosed drainage vein, and the remaining seven patients had a stenotic drainage vein. Flow rate and RI of the feeding artery of AVF were calculated by Color Doppler ultrasound (CDU) before and after balloon angioplasty and in the follow-up period. The flow rates and RI values before and after angioplasty and in the follow-up were compared. Increased flow rate and decreased RI values were detected after balloon angioplasty in all patients. We detected restenosis or thrombosis of drainage vein in six of the patients in the follow-up period. Decreased flow rate and increased RI values compared with previous measurements were calculated in these patients. Increased flow rate and decreased RI in the feeding artery of native dysfunctional AVF were demonstrated in patients who underwent balloon angioplasty on the stenotic vein. If restenosis develops in the follow-up period, the previous high resistance flow pattern is observed again. Feeding artery flow parameters as calculated by CDU can be used as a simple indicator of possible drainage vein problems of native AVF. | 18,791,955 |
[Psychotherapy for traumatized children and adolescents--cognitive-behavioral treatments]. | According to cognitive-behavioral models, both the avoidance of trauma-associated cues, as well as cognitive distortions of the trauma and the initial symptoms thereof lead to and subsequently maintain traumatic disorders. Trauma-focused cognitive behavioral therapy often starts with stabilizing interventions such as relaxation training. The main intervention consists of exposure to external trauma-associated cues (exposure in vivo) and to mental trauma reminders (exposure in sensu). Cognitive interventions aim to modify feelings of exaggerated guilt and shame. Of the different cognitive-behavioral programmes validated, trauma-focused cognitive-behavioral therapy yields the best evidence, particularly in the treatment of sexually abused children and adolescents. | 18,791,984 |
Facial nerve aberrations and their implications for cochlear implantation. | Cochlear implantation is a surgical procedure with progressively widening indications in the management of profound deafness. In the majority of cases the operation involves the formation of a posterior tympanotomy for electrode insertion. This process carries documented risks to the mastoid portion of the facial nerve. Here we summarize the variations found in the mastoid portion of the facial nerve, discuss the surgical methods that optimize nerve safety and present the Yorkshire Cochlear Implant Unit's series. | 18,791,997 |
Meningitis and cochlear implantation in Scotland. | Meningitis is responsible for a considerable proportion of profoundly deafened children. At the Scottish Cochlear Implant Centre, those attending for cochlear implant assessment with post-meningitic deafness were identified from 1989 to 1999. In those found suitable, findings at surgery were recorded. Meningitis notifications in Scotland from 1988 to 1998 were also studied. Out of 550 patients, 45 were found to have post-meningitic deafness. Of these, 32 were implanted and 12 were rejected. Of those implanted, 10 were affected by cochlear ossification. In five of these patients, a full insertion of a multichannel device was impossible and as a result, auditory rehabilitation was less satisfactory. Meningitis in Scotland appears to have been declining from 1988 to 1998. | 18,791,999 |
Multidimensional LC x LC analysis of phenolic and flavone natural antioxidants with UV-electrochemical coulometric and MS detection. | A comprehensive 2-D LC x LC system was developed for the separation of phenolic and flavone antioxidants, using a PEG-silica column in the first dimension and a C(18) column with porous-shell particles or a monolithic column in the second dimension. Combination of PEG and C18 or C8 stationary phase chemistries provide low selectivity correlations between the first dimension and the second dimension separation systems. This was evidenced by large differences in structural contributions to the retention by -COOH, -OH and other substituents on the basic phenol or flavone structure. Superficially porous columns with fused core particles or monolithic columns improve the resolution and speed of second dimension separation in comparison to a fully porous particle C(18) column. Increased peak capacity and high orthogonality in different 2-D setups was achieved by using gradients with matching profiles running in parallel in the two dimensions over the whole 2-D separation time range. Multi-dimensional set-up combining the LC x LC separation on-line with UV and multi-channel coulometric detection and off-line with MS/MS technique allowed positive peak identification. The Coularray software compensates for the effects of the baseline drift during the gradient elution and is compatible with parallel gradient comprehensive LC x LC technique. Furthermore, it provides significant improvement in the sensitivity and selectivity of detection in comparison to both UV and MS detection. The utility of these systems has been demonstrated in the analysis of beer samples. | 18,792,009 |
Construction of a new interface for comprehensive supercritical fluid chromatography x reversed phase liquid chromatography (SFC x RPLC). | The design of a new interface to hyphen high efficiency supercritical fluid chromatography (SFC) and fast RPLC in a comprehensive configuration is described. SFC x RPLC is a viable alternative to normal phase (NP) LC x RPLC and is characterized by high orthogonality. Compared to NPLC x RPLC an additional advantage is the expansion of supercritical carbon dioxide (CO(2)) when exposed to atmospheric pressure leading to fractions consisting of solvents that are miscible with the second dimension RPLC mobile phase. The interface consists of a two-position/ten-port switching valve equipped with two packed octadecyl silica (C(18)) loops for effective trapping and focusing of the analytes after elution from the SFC dimension. The addition of a water make-up flow to the SFC effluent prior to entering the loops is of fundamental importance to efficiently focus the solutes on the C(18) material and to reduce interferences of expanded CO(2) gas on the second dimension separation. The features of the system are illustrated with the analysis of a lemon oil sample. | 18,792,011 |
Fluorescent magnesium(II) coordination polymeric hydrogel. | A pH and mechano-responsive coordination polymeric gel was developed without the use of long chain hydrophobic groups. The hydrogel was synthesised by reacting the aqueous solution of Mg2+ with the basic aqueous solution of N-(7-hydroxyl-4-methyl-8-coumarinyl)-alanine. The gelation is attributed to the self-aggregation of 1D coordination polymers to form 3D nanostructures through non-covalent interactions to entrap water molecules. The freeze-dried hydrogel exhibits a fibrillar network structure with a uniform ribbon shape. UV/vis absorption studies illustrate that the hydrogel displays a typical pi-pi* transition. The fluorescence intensity of the hydrogel is enhanced drastically with a longer lifetime upon gel formation. Mechanical analysis including dynamic oscillation on shear, steady shear and creep (retardation-relaxation) testing have been performed to elucidate the supramolecular nature of the 3D assembly. Together with the viscoelastic properties and biocompatibility, the Mg2+ hydrogel may find utility as a novel soft material in biomedical applications. | 18,792,021 |
New DNA polymerase IIIC inhibitors: 3-subtituted anilinouracils with potent antibacterial activity in vitro and in vivo. | The development of resistance has rendered several antibiotics clinically ineffective, and there is an urgent medical need for potent and safe antibacterials with a novel and valid mode of action. To avoid cross-resistance, they should preferably inhibit targets that are not addressed by established antibiotics. In this respect, 6-anilinouracils represent a promising lead structure. They target the Gram-positive DNA polymerase IIIC, a target that is associated with a bactericidal mode of action. Moreover, they have no cross-resistance to marketed antibiotics. This paper describes the synthesis and biological characterization of structurally novel anilinouracils, some of which display potent in vivo efficacy in murine models of bacterial septicemia. | 18,792,034 |
Benzimidazolium salts as small, nonpeptidic and BBB-permeable human prolyl oligopeptidase inhibitors. | Prolyl oligopeptidase (POP) is a cytosolic serine peptidase that hydrolyzes proline-containing peptides at the carboxy terminus of proline residues. This peptidase has gained importance as a target for the treatment of cognitive disturbances of patients with neuropsychiatric diseases. Our research addresses the identification of POP inhibitors from a small focused library of polar heterocyclic compounds arising from multicomponent reactions. Two selective POP-specific inhibitors were identified on the basis of their inhibition of dipeptidyl peptidase IV. The most active compounds were evaluated for their in vitro transport through the blood-brain barrier (BBB) using a parallel artificial membrane permeability assay. Our results show for the first time that benzimidazolium salts are new POP-inhibitory scaffolds with properties of solubility, specificity, and lipophilicity that may allow them to cross the BBB by passive diffusion. These findings constitute an excellent starting point to synthesize new POP inhibitors with enhanced properties. | 18,792,035 |
Glutathione transferase: new model for glutathione activation. | Glutathione transferases are enzymes of the cellular detoxification system that metabolize a vast spectrum of xenobiotic and endobiotic toxic compounds. They are homodimers or heterodimers and each monomer has an active center composed of a G-site in which glutathione (GSH) binds and an H-site for the electrophilic substrate. When GSH binds to the G-site, the pKa value of its thiol group drops by 2.5 units; this promotes its deprotonation and, therefore, produces a strong nucleophilic thiolate that is able to react with the electrophilic substrate. The mechanism behind the deprotonation of the thiol group is still unknown. Some studies point to the fact that the GSH glutamyl alpha-carboxylate group is essential for GSH activation, whereas others indicate the importance of the active-center water molecules. On the basis of QM/MM calculations, we propose a mechanism of GSH activation in which a water molecule, acting as a bridge, is able to assist in the transfer of the proton from the GSH thiol group to the GSH glutamyl alpha-carboxylate group, after an initial GSH conformational rearrangement. We calculated the potential of mean force of this GSH structural rearrangement that would be necessary for the approach of both groups and we then performed a QM/MM ONIOM scan of water-assisted proton transfer. The overall free-energy barrier for the process is consistent with experimental studies of the enzyme kinetics. | 18,792,041 |
A dinuclear iron complex based on parallel malonate binding sites: cooperative activation of dioxygen and biomimetic ligand oxidation. | A ligand that offers two parallel malonate binding sites linked by a xanthene backbone, namely, Xanthmal2-, has been utilised to synthesise dinuclear FeII complex [Fe2(Xanthmal)2] (1). The reactivity of 1 in contact with O2 was investigated at -40 degrees C and room temperature. After activation of O2 through interaction with both iron centres the ligand is oxidised: at the Calpha position monooxygenation and peroxide formation occur, partially accompanied by C-C bond cleavage to yield alpha-keto ester groups. To reveal mechanistic details investigations concerning 1) peroxide decomposition, 2) the reactivity of a corresponding mononuclear complex, 3) the influence of monooxygenation of the ligand on the reactivity and 4) product formation in dependence on time were carried out. The results can be explained by postulating formation of high-valent Fe intermediates and ligand-to-metal electron transfer, and the mechanistic scheme derived includes several steps that mimic the (suggested) functioning of non-heme iron enzymes. In agreement with this proposal, ligand oxidation can also be performed catalytically. Furthermore, we show that via a competitive route [(Xanthmal)2Fe2O] (2) is formed, which is unreactive towards O2 and thus is a dead end with respect to ligand oxidation. Both compounds 1 and 2 were fully characterised, and their properties are discussed. | 18,792,042 |
Growth of three bacteria in arsenic solution and their application for arsenic removal from wastewater. | The present paper compares the arsenic removal capacities of three bacterial strains namely, Ralstonia eutropha MTCC 2487, Pseudomonas putida MTCC 1194 and Bacillus indicus MTCC 4374 form wastewater (simulated acid mine drainage) containing arsenic (As(III):As(V)::1:1), Fe, Mn, Cu and Zn in the concentration of 15 mg/l, 10 mg/l, 2 mg/l, 5 mg/l and 10 mg/l respectively, in bulk liquid phase. Growth patterns of these bacteria in presence of arsenic in solution as well as under starvation have also been investigated as the acid mine drainage normally does not contain organic carbon and also contains high arsenic. At the nutrient broth concentration of 1.25 g/l and in presence of 15 mg/l arsenic sufficient growth of these strains have been observed. However, growth of Ralstonia eutropha MTCC 2487 has been found slightly more than Pseudomonas putida MTCC 1194 and Bacillus indicus MTCC 4374. Arsenic removal capacities of Ralstonia eutropha MTCC 2487, Pseudomonas putida MTCC 1194 and Bacillus indicus MTCC 4374 from simulated acid mine drainage are approximately 67%, 60% and 61% respectively. It has also been observed that arsenic concentration of 15 mg/l prolongs the stationary phase of these strains. pH and temperature for the above studies have been maintained at 7.1 +/- 0.1 and 29 +/- 1 degrees C, respectively. | 18,792,057 |
Reliability and validity of the Childhood Cancer Survivor Study Neurocognitive Questionnaire. | Up to 40% of childhood cancer survivors may experience neurocognitive impairment in 1 or more specific domains. As such, regular monitoring has been recommended for patients exposed to cranial irradiation and/or antimetabolite chemotherapy. This study reports the results of a questionnaire developed to identify those survivors who may be experiencing neurocognitive problems. Participants for this study were 7121 members of the Childhood Cancer Survivor Study cohort (6739 survivors and 382 siblings). These participants completed a new neurocognitive questionnaire designed to assess functions commonly affected by cancer therapy, as well as a standard measure of emotional functioning. A measure of cognitive and emotional functioning was also completed on a subset of the patients roughly 7 years before the current questionnaire. Responses to the questionnaires among subgroups of survivors were then analyzed to examine the reliability and validity of the new neurocognitive questionnaire. Four reliable factors were identified that assessed task efficiency, emotional regulation, organization, and memory skills. These neurocognitive factors accurately discriminated survivors who were at "high risk" for neurocognitive dysfunction, because of neurologic abnormalities or a history of intensive focal cranial irradiation, from healthy "low-risk" survivors and siblings. The questionnaire demonstrated excellent reliability, as well as construct and discriminative validity. It appears to be a practical and efficient tool for monitoring neurocognitive outcomes in adult survivors of pediatric cancer. | 18,792,068 |
Identification of CXCL13 as a new marker for follicular dendritic cell sarcoma. | The homeostatic chemokine CXCL13 is preferentially produced in B-follicles and is crucial in the lymphoid organ development by attracting B-lymphocytes that express its selective receptor CXCR5. Follicular dendritic cells (FDCs) have been identified as the main cellular source of this chemokine in lymphoid organs. Recently, genome-wide approaches have suggested follicular CD4 T-helper cells (T(H)F) as additional CXCL13 producers in the germinal centre and the neoplastic counterpart of T(H)F (CD4+ tumour T-cells in angioimmunoblastic T-cell lymphoma) retains the capability of producing this chemokine. In contrast, no data are available on CXCL13 expression on FDC sarcoma (FDC-S) cells. By using multiple approaches, we investigated the expression of CXCL13 at mRNA and protein level in reactive and neoplastic FDCs. In reactive lymph nodes and tonsils, CXCL13 protein is mainly expressed by a subset of FDCs in B-cell follicles. CXCL13 is maintained during FDC transformation, since both dysplastic FDCs from 13 cases of Castleman's disease and neoplastic FDCs from ten cases of FDC-S strongly and diffusely express this chemokine. This observation was confirmed at mRNA level by using RT-PCR and in situ hybridization. Of note, no CXCL13 reactivity was observed in a cohort of epithelial and mesenchymal neoplasms potentially mimicking FDC-S. FDC-S are commonly associated with a dense intratumoural inflammatory infiltrate and immunohistochemistry showed that these lymphocytes express the CXCL13 receptor CXCR5 and are mainly of mantle zone B-cell derivation (IgD+ and TCL1+). In conclusion, this study demonstrates that CXCL13 is produced by dysplastic and neoplastic FDCs and can be instrumental in recruiting intratumoural CXCR5+ lymphocytes. In addition to the potential biological relevance of this expression, the use of reagents directed against CXCL13 can be useful to properly identify the origin of spindle cell and epithelioid neoplasms. | 18,792,075 |
Early phase of maternal skin carcinogenesis recruits long-term engrafted fetal cells. | During pregnancy, fetal cells enter the maternal circulation. These may be mesenchymal stem cells, haematopoietic or endothelial progenitors, which may persist for decades and be recruited to damaged maternal tissues. Recently, fetal cells were also identified in tumour tissues such as cervical cancer and breast carcinomas. However, the timing of malignant tumour infiltration was not demonstrated. In this study, we used two step carcinogenesis to assess the presence of fetal cells in early phases of skin tumour formation in previously pregnant mice. Wild-type female C57/BL6 mice were bred to transgenic mice for EGFP. After delivery, skin papillomas were induced by two-step carcinogenesis. The tumours were dissected 9 months after gestation. Fetal cells were identified in 75% of cutaneous papillomas (9/12 tumours), but never in normal skin from the same mice. Fetal cells expressed von-Willebrand factor, and less frequently CD45 or cytokeratin but did not express the tumoral epidermal keratins. Our study shows that long-term engrafted fetal cells home to early stage skin tumours where they participate in formation of the stroma. | 18,792,101 |
Recognition of familiar melodies by adult cochlear implant recipients and normal-hearing adults. | The purpose of this study was to compare melody recognition and pitch perception of adult cochlear implant recipients and normal-hearing adults and to identify factors that influence the ability of implant users to recognize familiar melodies. Forty-nine experienced cochlear implant recipients and 18 normal-hearing adults were tested on familiar melody recognition. The normal-hearing adults were significantly (p < 0.0001) more accurate than implant recipients. Implant recipients showed considerable variability in perception of complex tones and pure tones. There were significant negative correlations between melody recognition, age at the time of testing, length of profound deafness and complex-tone perception, and significant positive relations between melody recognition and speech recognition scores. | 18,792,110 |
Localization performance of unilateral cochlear implant users for speech, tones and noise. | Bilateral cochlear implants aim to improve sound localization compared to monaural implants, among other potential benefits. Monaural cochlear implants should not support localization in the horizontal plane as there are no interaural level and time difference cues available, although some previous studies have suggested limited capability. As background to other studies of bilateral implantation, the localization abilities of 18 monaural cochlear implantees were investigated experimentally in an anechoic chamber, using various sound stimuli with different amounts of temporal information. The effects of head movement and reverberation were also investigated. Localization performance was found to be close to chance for all stimuli. It is confirmed that monaural cochlear implants are unable to support useful auditory sound localization, even when head movements are allowed. | 18,792,202 |
Refractory severe facial nerve cross-stimulation and loss of auditory sensation after ten years of uneventful cochlear implant use. A rare and challenging case. | Facial nerve stimulation after cochlear implantation has been well described. When the implant is first activated it is usually possible to 'programme out' the unwanted cross-stimulation. We report an exceptional case of delayed facial nerve stimulation and auditory failure after ten years of uncomplicated implant use. This sudden change proved refractory to reprogramming strategies. The patient refused contralateral implantation as he felt there was residual aided hearing. The implant was removed and replaced. Integrity testing of the explanted device showed it to be functioning normally. Severe facial nerve cross-stimulation persisted and the patient failed to regain his previous auditory sensation. Subsequently, despite extensive investigation and a trial of fluoride therapy, after a third implant he has performed equally badly leading to non-use. | 18,792,205 |
Research directions for future generations of cochlear implants. | Physiological and psychophysical research indicates that improved hearing in noise and music appreciation are likely with cochlear implants, with better reproduction of the fine temporospatial patterns of neural response in the auditory pathways due to phase differences in neuron firing patterns as the result of the basilar membrane travelling wave. An initial speech-processing strategy, to in part reproduce this information, is showing better frequency discrimination and musical perception. However, more exact reproduction is likely with a new generation electrode array which could involve the use of neurotrophins and inherently conducting polymers. The siting and design of this, as well as safety, needs further investigation before it is implemented. | 18,792,214 |
Sound localization in patients with unilateral cochlear implants. | To evaluate sound localization ability in totally deaf patients with unilateral cochlear implants and to estimate the ability to improve this function by training. A controlled case series. Nine patients with monaural cochlear implants were asked to identify the source of 50 randomly distributed sound stimuli coming from five different directions anteriorly or laterally. After some training, patients were retested. There were two control groups. One comprised nine adults with normal hearing, and the other comprised nine adults with normal hearing but one ear plugged. The mean initial score of the study group (maximal score 100) was 41.5 (range 23-63). Patients who had used cochlear implants longer had better sound localization ability (Spearman's correlation coefficient = 0.92). On retesting, after an average of 6.3 training sessions, their mean score improved to 66 (range 32-95), (p = 0.008). The improvement was more pronounced in postlinguals than in prelinguals (p = 0.016). Spontaneous development of sound localization ability in totally deaf patients with unilateral cochlear implants is proportional to the time interval between implantation and initial testing. Improvement appears to be influenced by training, and to be greater in postlingual than in prelingual implantees. | 18,792,315 |
A comparison of cochlear implant processing strategies in children using speech pattern audiometry. | The aim of this study was to use Speech Pattern Audiometry (SPA) to compare phoneme perception performance between SPEAK and ACE processing strategies with children using the Nucleus 24 cochlear implant. Listeners were evaluated in terms of ability to identify two synthetic word pairs, one signalling a voicing contrast and the other signalling a place of articulation contrast. For both word pairs, ACE was associated with more 'normal' phoneme boundaries than SPEAK. There was also a non-significant trend for better identification ability with ACE compared to SPEAK. The study suggests that there may be a place for SPA as part of the clinical battery of tests used for evaluation of cochlear implant speech processing strategies in children. Copyright (c) 2005 John Wiley & Sons, Ltd. | 18,792,337 |
Language and theory-of-mind development in prelingually deafened children with cochlear implants: a preliminary investigation. | One cognitive domain in which deaf children are known to lag behind their hearing peers is that of 'theory of mind'. Impoverished early conversational experience and deprivation of discussion about intangible mental states are seen as likely contributors to this deficit. The present study explored the relation between language and theory-of-mind capabilities in prelingually deafened children aged 4 to 11 years who were cochlear implant users. The children completed theory-of-mind tasks that indexed their ability to reason about conflicting mental representations, namely the understanding of false belief and the distinction between appearance and reality. Controlling for age, language ability was found to correlate positively and reliably with theory-of-mind performance. | 18,792,371 |
Symposium on Training Programs in Pathology (VII European Congress of Pathology, Valencia, 1979). An introduction to the symposium: participants, aims--the Spanish programme; proposed general conclusions. | The need for learning pathology as a physical substratum of disease is unquestioned. Thus at the undergraduate level opinions vary only on the best time for teaching pathology, the length and the depth of teaching, the degree of integration with clinical disciplines, the use of audiovisual aids, the direct involvement of the students with routine material, the nature of evaluation tests, and so on. Postgraduate pathology should ideally reach all physicians, at least in the field in which they specialize. As for future pathologists, they need to understand the three way role expected from them in medicine: 1. A proper knowledge of morphopathology in close relation with etiology, pathogenesis, and clinical consequences; 2. A scientific attitude of permanent learning through experience and study, and 3. Availability of their experience for the progress of medicine through teaching, writing, and quality control at their hospitals. To reach these goals, pathology should be taught in well functioning, active, and adequatly staffed hospital departments, through long, progressive, controlled and flexible residency programs under some kind of advice and supervision of national and even international Agencies. These advisory bodies should attempt to permanently evaluate the real needs and desirable location of pathologists in the future, and propose any needed changes concerning their background, education, and professional role. | 18,792,466 |
The risk of cancer in relationship to diet. | Globally, colorectal cancer is the leading cause of mortality due to malignant diseases. Probiotics are live microbial food supplements or functional foods containing specific nonpathogenic organisms that beneficially affect the host by improving the intestinal microbial balance. Therefore they can be used as an innovative tools to alleviate intestinal inflammation, normalize gut mucosal dysfunction, and down-regulate hypersensitivity reactions. In the past decade, there has been a dramatic increase of experiments and studies documenting prophylactic and therapeutic benefits of probiotics and prebiotics in order to reduce the risk of chronic civilization diseases. The current knowledges on probiotics qualify them as the pivotal components of self-care and complementary medicine (Ref. 27). | 18,792,488 |
The comparative study of metacognition: sharper paradigms, safer inferences. | Results that point to animals' metacognitive capacity bear a heavy burden, given the potential for competing behavioral descriptions. In this article, formal models are used to evaluate the force of these descriptions. One example is that many existing studies have directly rewarded so-called uncertainty responses. Modeling confirms that this practice is an interpretative danger because it supports associative processes and encourages simpler interpretations. Another example is that existing studies raise the concern that animals avoid difficult stimuli not because of uncertainty monitored, but because of aversion given error-causing or reinforcement-lean stimuli. Modeling also justifies this concern and shows that this problem is not addressed by the common practice of comparing performance on chosen and forced trials. The models and related discussion have utility for metacognition researchers and theorists broadly, because they specify the experimental operations that will best indicate a metacognitive capacity in humans or animals by eliminating alternative behavioral accounts. | 18,792,496 |
Evidence against a speed limit in multiple-object tracking. | Everyday tasks often require us to keep track of multiple objects in dynamic scenes. Past studies show that tracking becomes more difficult as objects move faster. In the present study, we show that this trade-off may not be due to increased speed itself but may, instead, be due to the increased crowding that usually accompanies increases in speed. Here, we isolate changes in speed from variations in crowding, by projecting a tracking display either onto a small area at the center of a hemispheric projection dome or onto the entire dome. Use of the larger display increased retinal image size and object speed by a factor of 4 but did not increase interobject crowding. Results showed that tracking accuracy was equally good in the large-display condition, even when the objects traveled far into the visual periphery. Accuracy was also not reduced when we tested object speeds that limited performance in the small-display condition. These results, along with a reinterpretation of past studies, suggest that we might be able to track multiple moving objects as fast as we can a single moving object, once the effect of object crowding is eliminated. | 18,792,507 |
An attentional blink for sequentially presented targets: evidence in favor of resource depletion accounts. | Several accounts of the attentional blink (AB) have postulated that this dual-target deficit occurs because of limited-capacity attentional resources being devoted to processing the first target at the expense of the second (resource depletion accounts; e.g., Chun & Potter, 1995). Recent accounts have challenged this model (e.g., Di Lollo, Kawahara, Ghorashi, & Enns, 2005; Olivers, van der Stigchel, & Hulleman, 2007), proposing instead that the AB occurs because of subjects' inability to maintain appropriate levels of attentional controlwhen targets are separated by distractors. Accordingly, the AB is eliminated when three targets from the same attentional set are presented sequentially in a rapid serial visual presentation (RSVP) stream. However, under such conditions poorer identification of the first target is typically observed, hinting at a potential trade-off between the first and subsequent target performances. Consistent with this hypothesis, the present study shows that an AB is observed for successive targets from the same attentional set in an RSVP stream when the first target powerfully captures attention. These results suggest that resource depletion contributes significantly to the AB. | 18,792,508 |
Memorial consequences of imagination in children and adults. | Recent work with adults suggests that imagination can impair later recall of previously encoded events but can improve recall of subsequently encoded events. The present study examined the memorial consequences of imagination in children. Kindergartners, first and fourth graders, and young adults studied two successively presented lists of items. Between the two lists, participants were given an imagination task supposed to create a change in mental context. As expected, in adults, the imagination task impaired recall of the previously encoded material (List 1) and improved recall of the subsequently encoded material (List 2). In children, significant List 1 impairment was present from first grade on, but even fourth graders failed to show improvement for List 2. The results challenge a purely context-based explanation of the memorial costs and benefits of imagination. Instead, they suggest that the two effects are mediated by different mechanisms with different developmental trajectories. | 18,792,512 |
Embodied relations are encoded in language. | Studies of embodied cognition have shown that comprehenders process iconic word pairs (attic-basement) more quickly than reverse-iconic pairs (basement-attic) when the pairs are presented to them in a vertical spatial arrangement. This effect disappears in a horizontal spatial arrangement. This has been claimed to show that comprehenders perceptually simulate these word pairs. A complementary explanation is that linguistic conceptualizations (word order) reflect prelinguistic conceptualizations (spatial iconicity), whereby comprehenders use these linguistic conceptualizations in the comprehension process. The results of corpus linguistic, rating, and semantic judgment studies reported here supported this explanation: Iconic word pairs were more frequent than reverse-iconic word pairs; frequency of word order explained response times in a semantic judgment task better than iconicity did; and when iconic word pairs were presented in a horizontal arrangement, the iconicity effect disappeared, but the word order effect remained. These findings show that spatial iconicity patterns are reflected in word order patterns and that comprehenders are sensitive to these word order patterns in language-processing tasks. | 18,792,513 |
Seroprevalence study on the diffusion of the West Nile virus among blood donors, healthcare workers, jockeys, grooms and fowlers, veterinary surgeons and hunters in Messina (Italy). | West Nile virus (WNV) is a mosquito-transmitted flavivirus widely distributed in Africa, Middle East, Asia, Southern Europe and in 1999 was first identified in the United States as a cause of disease in New York City. It mainly circulates among birds, but can infect many species of mammals. Epidemics can occur in rural as well as urban areas. 1,280 sera were collected during 2006 from 80 stable workers, as jockey and grooms, 100 fowlers, 500 blood donors, 600 healthcare workers, 100 veterinary surgeons and 100 hunters in the Messina province to evaluate the prevalence of the WNV infection, by ELISA test, in relation to risk exposure or not. None of the 1280 subjects examined has shown positive for antibodies anti WN virus. Among the strategies of control and surveillance, finally, in our opinion, are and will be indispensable the programs of continuous antibody survey in all the risk categories and in the general population in order to succeed to preview which effects could have the presence of infections from WNV, also imported from other zones where the virus is constantly present, in future and which it could be the impact of geographic factors on the epidemic spread of the disease. | 18,792,530 |
[Epidemiology of cardiac tumors in adults in Lebanon]. | Primary cardiac tumors are rare but potentially fatal. No studies have discussed this issue yet on the national level. We describe the epidemiology of cardiac tumors in adults in Lebanon. The data were taken from the hospitals, the patients and/or their doctors by means of a questionnaire. Fifty-seven cases of cardiac tumors were found, mainly myxomas in the left atrium. Dyspnea was the most frequent symptom. Transthoracic echocardiography was the main diagnostic tool. Transesophageal echocardiography was inconstantly made, scanner and MRI rarely while contrast echocardiography has never been used. Almost half of the patients had a follow-up and none had a familial screening. The collected data urged us to propose a unique and homogenous strategy for diagnosis, treatment and follow-up of cardiac tumors in Lebanon. | 18,792,552 |
[Evidence for expression of a nifedipine resistant L-type calcium current in human atrial cardiomyocytes]. | In the heart, two types of calcium currents were described, the L- and T-type. In addition to these two types, a dihydropyridine-resistant Ca2+ component has been described to be up-regulated in rat ventricular cardiomyocytes during their differentiation- dedifferentiation process. The aim of our study is to examine if such calcium current component is present in human cardiomyocytes. The patch clamp technique was used to record Ca2+ current in atrial cells. In the presence of 2 microM nifedipine, residual current was activated (-2.7 +/- 0.7 pA/pF, n = 6) in the same voltage range as the L-type, nifedipine-sensitive Ca2+ current (-2.1 +/- 0.4 pA/pF, n = 6), but its steady-state inactivation was negatively shifted by 10 mV. This nifedipine-resistant Ca2+ current was completely blocked by 500 microM cadmium chloride and significantly enhanced by 1 microM isoproterenol (-7.5 +/- 0.5 pA/pF, n = 6; p <0.01). These results give evidence that a nifedipine-resistant Ca2+ current, similar to the one which has been shown to be developmentally expressed in rat ventricular cardiomyocytes, is observed in human atrial cells. Its molecular identity, its expression level as well as its role in pathophysiologic conditions remain to be studied. | 18,792,554 |
[Screening of risk groups for discovering intracranial aneurysms before rupture]. | In development of intracranial aneurysms contribute genetic factors together with smoking, hypertension, diabetes mellitus. Epidemiology studies suggest that as many as 5% of people harbour a cerebral aneurysm by age 75. Rupture of cerebral aneurysm is the most frequent cause of spontaneous subarachnoid haemorrhage (up to 80%.) Annual incidence of SAH is 10-14/100 000, but only 15-20% of aneurysms will rupture, and that will happen probably between 40-60 years. The morbidity and mortality of aneurismal subarachnoid (SAH) continues to be high. It is not possible to predict who has aneurysm and is it going to bleed or not, but it is possible to reveal high risk groups (polycystic kidney disease, Ehlers-Danlos sy, Marphan sy, family history of cerebral aneurysms, suspect de novo aneurysm formation in patients with prior history of cerebral aneurysm). Reviewing data from literature and reporting cases from each group with high risk, that have been screened and aneurysms discovered, authors wish to focus interest on this matter and propose screening program for these groups of patients. The mortality and morbidity in cases treated before rupture is significantly lower than after SAH, so screening programs could save many lives. According to our preliminara data, mostly based on control angiographies after 8-10 zears in patients previouslz operated for intracranial aneurysmas, from 15 angipgraphies 4 revealed new aneurysms (26% in 10 years period) with total number of 6 de novo formed aneurysms, which is not valid due to small number of patients but strongly suggests the importancy of screening program for risk groups. | 18,792,572 |
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