title stringlengths 0 1.13k | abstract stringlengths 1 15.7k | PMID int64 22 36.5M |
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[The mortality of the able-bodied population in the Irkutsk oblast]. | The comprehensive evaluation of the irrevocable demographic losses among the able-bodied population in Irkutsk oblast. The quantitative structural analysis was implemented as applied to the characteristics of mortality of this population contingent. The peculiarities of formation of the vital potential of the economically active population. The structure and hierarchy of factors conditioning the worst losses of vital potential | 18,810,790 |
Uncontrolled asthma means missed work and school, emergency department visits for many Californians. | In 2005, three million Californians reported that they had current asthma. Despite advances in therapy, asthma remains a disease that is not optimally controlled in many Californians. Inadequately controlled asthma can result in missed work and school and emergency department visits. Asthma was responsible for an estimated 1.9 million missed days of school and two million days of missed work in California in 2005. In addition, more than 475,000 children and adults in California went to the emergency department or urgent care center because of asthma. There are 659,000 children and adults who suffer from asthma symptoms every day or every week (22% of those with current asthma). These Californians suffering from frequent asthma symptoms have higher rates of missing school or work due to their asthma, visiting the emergency department or urgent care for their asthma, and rating their overall health as fair or poor. Improvements in access to health care, asthma management and avoidance of triggers can help these Californians reduce the severity of their asthma burden. Using data from the 2005 California Health Interview Survey (CHIS 2005), this policy brief examines the burden associated with frequent asthma symptoms among those with current asthma, and identifies key opportunities for reducing and controlling disease activity in these asthma sufferers. Asthma is a chronic disease that causes the airways of the lungs to become inflamed and more sensitive to constriction, making it harder to breathe. Current asthma refers to people who have been diagnosed with asthma and who report they still have asthma, or have had an episode or attack in the previous year. Frequent asthma symptoms are defined as experiencing asthma symptoms every day or every week. | 18,810,806 |
Characteristics of enterotoxin H-producing Staphylococcus aureus isolated from clinical cases and properties of the enterotoxin productivity. | Staphylococcal enterotoxin H (SEH) is predicted to be involved in staphylococcal food poisoning. To characterize SEH-producing Staphylococcus aureus isolates from staphylococcal food poisoning cases in Japan, we investigated the relationship between SEH production and coagulase serotype, which is an epidemiological marker, and compared the properties of SEH production with those of staphylococcal enterotoxins A (SEA) and B (SEB). SEH production was determined by a newly developed sandwich enzyme-linked immunosorbent assay. Eighty-six (59.7%) of 144 isolates from staphylococcal food poisoning cases produced SEH. Seventy-one of the SEH-producing isolates simultaneously produced SEA, SEB, or both. All SEH-producing isolates belonged to coagulase type VII, which was the predominant type, representing 99 (68.8%) of 144 isolates. The amount of SEH produced in brain heart infusion was almost the same as the amount of SEA and approximately 10-fold lower than that of SEB. SEH and SEA were produced mainly during the late exponential phase of growth, whereas SEB was produced mostly during the stationary phase. The production levels of SEH and SEA were gradually affected by decreases in water activity, but the production of SEB was greatly reduced under conditions of low water activity. These findings indicate that SEH-producing S. aureus isolates are of high prevalence in staphylococcal food poisoning cases. Given the unique epidemiological characteristic of these isolates, SEH and SEA probably are responsible for food poisoning. | 18,810,869 |
Birthweight and gestational age by ethnic group, England and Wales 2005: introducing new data on births. | Low birthweight babies and babies born preterm are at increased risk of morbidity and mortality in the first year of life, as well as in the longer-term. Since information on ethnic group is not recorded at birth registration in England and Wales, it has not been possible to produce routine statistics on birthweight or gestational age by ethnic group. A new system, introduced in 2002, for allocating NHS numbers at birth (NN4B) provided the opportunity to obtain ethnic group information. The NN4B record includes information on the ethnic group of the baby classified according to the 2001 Census categories. This paper presents the first analyses of ethnic differences in birthweight and gestational age at birth for England and Wales as a whole. Utilising NN4B records linked with birth registration records for all births occurring in England and Wales in 2005, birthweight and gestational age distributions, including the percentages low birthweight and preterm, are compared between ethnic groups. The paper also examines how parental socio-demographic circumstances vary by ethnic group. | 18,810,886 |
Maori women's views on smoking cessation initiatives. | Smoking is particularly prevalent among Maori women over the age of 15 years and remains a concern despite anti-smoking campaigns. This raises questions about the effectiveness of current smoking cessation initiatives as mainstream tobacco control programmes have not benefited Maori to the same extent as non-Maori. Limited research is available on the effectiveness of smoking cessation initiatives for Maori. In this descriptive qualitative study five Maori women who had ceased smoking were interviewed about such initiatives and what was more likely to influence Maori women to quit. A focus group was used to discuss smoking cessation initiatives and the data were thematically analysed using Boyatzis' (1998) approach. Two themes were identified: (a) Transmission of Whanau (immediate and extended family) Values that includes the sub-categories whanau experiences, being mothers, and role models; and (b) Factors Crucial in Influencing Change that includes the sub-categories choices and exercising own will, a positive perception of self and a Maori approach. The findings provide insight for nurses into Maori women's perspectives. These highlight the importance of whanau and supportive relationships, and can be used to inform strategies to assist Maori women in smoking cessation. | 18,810,902 |
Ethical decision-making for multiple prescription dentistry. | Technology provides a selection of treatment choices for dental problems. Dental ethics must be applied to the development of a treatment plan and the selection of methods. Treatment options should consider the patient's circumstances and desires as well as the dentist's decision as it relates to best practices in dentistry. This article presents four case studies that illustrate the process of ethical decision-making for the appropriate treatment. | 18,810,913 |
An analysis on flavonoids contents in Mao Luang fruits of fifteen cultivars (Antidesma bunius), grown in northeast Thailand. | This investigation was carried out at the Department of Biotechnology, Faculty of Technology, Mahasarakham University, Mahasarakham Province, Northeast Thailand. The study aimed to analyze flavonoids contents in ripe fruits of fifteen Mao Luang cultivars (Antidesma bunius) harvested from dipterocarp forest of the mountainous areas of Phupan Valley, Sakon Nakhon Province, Northeast Thailand. The experiment was laid in a Completely Randomised Design (CRD) with five replications. The fifteen cultivars were used as treatments. An amount of 2 kg of ripe fruits of each cultivar was collected and extracted for juice solutions. The analysis was carried out with the use of RP-HPLC laboratory system. The results showed that fruits of the fifteen Mao Luang cultivars contained three different kinds of flavonoids, i.e., catechin, procyanidin B1 and procyanidin B2. These three chemical compounds were the major flavonoids in all analyzed fruit samples of the fifteen cultivars. The highest amount of procyanidin B1 was found with Lompat followed by Maeloogdog with values of 4122.75 and 3993.88 mg 100 g(-1) of fresh weight, respectively and the highest amount of procyanidin B2 was found with Sangkrow 2 followed by Fapratan with values of 5,006.39 and 3,689.42 mg 100 g(-1) of fresh weight, respectively. Catechin contents in fruits of the fifteen cultivars varied from 73.39 to 316.22 mg 100 g(-1) of fresh weight for Sangkrow 5 and Fapratan, respectively where Fapratan was the highest among the fifteen cultivars followed by Sangkrow 2 with values of 316.22 and 175.40 mg 100 g(-1) of fresh weight, respectively. In terms of grand total amounts of flavonoids, Sangkrow 2 was the best followed by Fapratan, Sangkrow 1 and Maeloogdog, whilst the rest were of secondary importance. | 18,810,968 |
Plant regeneration and floral bud formation from intact floral parts of African violet (Saintpaulia ionantha H. Wendl.) cultured in vitro. | Intact immature flower buds of African violet (Saintpaulia ionantha H. Wendl.) were used as explant sources for in vitro studies. The effect of exogenous hormones, NAA and BAP on the indirect organogenesis of this species was observed. Callus was formed on the cut end (base) of pedicels of floral buds where they were in contact with the medium. When maintained on the same medium, callus was differentiated into adventitious shoots after 10 weeks in culture. MS media supplemented with 2.0 mg L(-1) NAA and 1.0 mg L(-1) BAP gave the highest number of sterile or vegetative floral buds from the surface of callus of the explants, but these buds failed to develop further. The floral buds were expanded as abnormal flowers. The floral structures were smaller in size compared to intact flowers. Petals (corolla) were white to purple in colour but did not form any reproductive organs, i.e., stamens or pistils. All sterile or vegetative floral buds and abnormal flowers survived for 3 months in culture but failed to reach anthesis. | 18,810,979 |
Biotransformation of glabratephrin, a rare type of isoprenylated flavonoids, by Aspergillus niger. | Microbial transformation of glabratephrin, the major isolated compound from Tephrosia purpurea, afforded pseudosemiglabrin. The formation of the transformed compound seems to be performed via ring opening-closure of a five-membered ring causing transformation from a spiro into a fused system. The structure of the transformed compound was determined by comprehensive NMR studies, including DEPT, COSY, HMQC, NOE and MS. | 18,811,002 |
Microtitre plate assay for biofilm formation, production and utilization of hydroxybiphenyl by Rhodococcus sp. isolated from gasoline-contaminated soil. | Gasoline-contaminated soil from Isfahan, Iran was selected to isolate a bacterium capable of desulfurizing dibenzothiophene (DBT). The isolated strain was named R1 and identified as Rhodococcus erythropolis through biochemical tests as well as sequencing of 16S rRNA gene. This strain could efficiently produce 2-hydroxybiphenyl (HBP) from DBT via the 4S metabolic pathway. The highest HBP amount was produced at 2 mM DBT with addition of glucose (10 g l(-1)), ethanol (3 g l(-1)), glycerol (2 g l(-1)) or succinate (10 g l(-1)) as carbon sources at pH 7. Highest respiration and growth rates were observed by microplate titration on 0.1 mM HBP, and addition of 0.2 mM HBP to glucose (1 g l(-1)) and DBT (0.3 mM) could inhibite the respiration of the isolate. The isolated strain could grow up to 0.4 mM of HBP when it is used with mineral sulfur as sole sulfur source. To the best of our knowledge this is the first report on a microtiter assay for the production and utilization of HBP by Rhodococcus. | 18,811,008 |
Decreased DNA repair capacity of UV-irradiated cells following interferon treatment. | The aim of this study was to examine the effect of interferons (IFNs) on the recovery of UV-damaged cells by means of measuring cell viability rates. The influence of the recombinant human interferons IFN-alpha, IFN-beta and IFN-gamma on the repair capacity of the UV-irradiated human cell lines WISH and HeLa was studied. The ability of cells to repair UV-induced damage was determined by the comet assay and both short- and long-term survival assays in proliferating cell cultures. We found that INFs negatively regulated DNA repair in cells damaged by UV light. One day after treatment, in both cell lines tested, IFN-alpha had a stronger inhibitory effect than IFN-gamma. Combined treatment with different IFNs exhibited a stronger inhibitory effect on cell recovery than treatment with each of them. The protein kinase inhibitor wortmanin further aggravated the effect of IFNs on cell survival. | 18,811,009 |
Idiopathic gingival fibromatosis: a review of the literature and a case report. | Gingival fibromatosis is characterized by localized or generalized fibrous enlargement of the gingivae, mainly around permanent teeth. Gingival fibromatosis affects only the masticatory mucosa and does not extend beyond the muco-gingival junction. This article describes an unusual case of idiopathic gingival fibromatosis with delayed eruption of permanent teeth in an 8 year-old boy. The pathogenic mechanisms that bring about gingival fibromatosis are discussed. | 18,811,080 |
A comparison of two liner materials for use in the ferric sulfate pulpotomy. | The aim of this study is to compare the success rate obtained when applying either a calcium hydroxide (Dycal) base or a zinc oxide-eugenol (Kalzinol) base following the traditional ferric sulfate pulpotomy. Patients were either treated in the chair or under general anaesthesia. All teeth had to have radiographic evidence of caries close to the pulp. After haemostasis was achieved with damp cotton pellets, ferric sulfate was applied to the pulpal stumps. Half of the cases then received a Dycal base followed by a cured layer of Vitrebond and a permanent amalgam restoration. The other half of the cases received a base of zinc oxide-eugenol (Kalzinol) followed by an amalgam restoration. The cases were followed up every 6 months for one year (ie. 2 follow-up visits). Radiographs were taken at each follow-up visit. Overall, teeth treated with Dycal demonstrated a higher failure rate when compared with those that received the Kalzinol base. Abscess formation and internal resorption were the most common causes of failure. Even though the Kalzinol base demonstrated greater success, there were still quite a few failures. This study demonstrates that calcium hydroxide cannot be recommended as a medicament in primary tooth pulpotomies. | 18,811,097 |
Empirical support for a fissure sealant placement timeframe protocol for black South Africans. | It is recommended that fissure sealants should be placed within four years after eruption. Due to considerable variations in the eruption times of molar teeth, this recommendation is of limited value from a public health perspective. This study, therefore, sought to provide empirical support for a public health fissure sealant placement timeframe protocol. The first and second molar eruption patterns of black South African children aged five to seven and 11 to 16 years were analysed in relation to caries experience using the 1999/2002 National Children's Oral Health Survey. By seven years of age, 90% of first molars had erupted with a caries experience of 3%. By 14 years of age the erupted first molars caries experience was 20%. The 13- and 14-year-olds presented with 86% and 98% erupted second molars with a caries experience of 11% and 20%, respectively. The study findings suggest that during school-based fissure sealant programmes involving black South African children, first molars should be targeted at age seven (Grade 1), or as soon as possible thereafter. However, caries protection may still be achieved until thirteen years of age (Grade 7). Furthermore, second molars should be sealed between the age of 11 and 13 years (grades 5-7). | 18,811,098 |
Spectroscopic and computational studies of (mu-oxo)(mu-1,2-peroxo)diiron(III) complexes of relevance to nonheme diiron oxygenase intermediates. | With the goal of gaining insight into the structures of peroxo intermediates observed for oxygen-activating nonheme diiron enzymes, a series of metastable synthetic diiron(III)-peroxo complexes with [Fe(III)(2)(mu-O)(mu-1,2-O(2))] cores has been characterized by X-ray absorption and resonance Raman spectroscopies, EXAFS analysis shows that this basic core structure gives rise to an Fe-Fe distance of approximately 3.15 A; the distance is decreased by 0.1 A upon introduction of an additional carboxylate bridge. In corresponding resonance Raman studies, vibrations arising from both the Fe-O-Fe and the Fe-O-O-Fe units can be observed. Importantly a linear correlation can be discerned between the nu(O-O) frequency of a complex and its Fe-Fe distance among the subset of complexes with [Fe(III)(2)(mu-OR)(mu-1,2-O(2))] cores (R = H, alkyl, aryl, or no substituent). These experimental studies are complemented by a normal coordinate analysis and DFT calculations. | 18,811,130 |
Sn(x)Pt4Sn(y)Sb(12-y): a skutterudite with covalently bonded filler. | A new phase, Sn(x)Pt4Sb(12-y)Sn(y), has been prepared from the elements. It exhibits a wide range of homogeneity with 0.3(2) < or = x < or = 1.0(2) and 4.2(2) < or = y < or = 7.0(2). The crystal structure and the composition were established by single-crystal and powder X-ray diffraction as well as wavelength-dispersive X-ray analysis measurements and were supported by nuclear magnetic resonance experiments. The compound is the first representative of the filled-skutterudite family with the filler atoms not located at the center of the cavity but covalently bonded to the cavity's wall, as confirmed by the analysis of chemical bonding with the electron localizability indicator. The Sn and Sb atoms share the framework site with different coordinate parameters caused by the difference in atomic size; additional tin atoms are located in the cavities of the framework. The material is a diamagnet in the whole composition range. In agreement with the calculated electronic density of states, the material reveals a metallic behavior in electronic transport. The absolute values of electrical resistivity vary with the tin-to-antimony ratio. | 18,811,146 |
DNA-binding and physical studies of Pt(4'-NR2-trpy)CN+ systems (trpy = 2,2':6',2''-terpyridine). | This paper focuses on DNA-binding interactions exhibited by Pt(dma-T)CN(+), where dma-T denotes 4'-dimethylamino-2,2':6',2''-terpyridine, and includes complementary studies of the corresponding pyrr-T complex, where pyrr-T denotes 4'-(N-pyrrolidinyl)-2,2':6',2''-terpyridine. The chromophores are useful for understanding the interesting and rather intricate DNA-binding interactions exhibited by these and related systems. One reason is that the terpyridine ligands employed provide intense visible absorption and enhanced photoluminescence signals. Incorporating cyanide as a coligand further aids analysis by suppressing covalent binding. Physical methods utilized include X-ray crystallography for structures of the individual inorganic complexes. Viscometry as well as spectral studies of the absorbance, emission, and circular dichroism (CD) yield information about interactions with a variety of DNA hosts. Although there is no sign of covalent binding under the conditions used, most hosts exhibit two phases of uptake. Under conditions of high loading (low base-pair-to-platinum ratios), the dma-T complex preferentially binds externally and aggregates on the surface of the host, except for the comparatively rigid host [poly(dG-dC)]2. Characteristic signs of the aggregated form include a bisignate CD signal in the charge-transfer region of the spectrum and strongly bathochromically shifted emission. When excess DNA is present, however, the complex shifts to intercalative binding, preferentially next to G[triple bond]C base pairs if available. Once the complex internalizes into DNA it becomes virtually immune to quenching by O2 or solvent, and the emission lifetime extends to 11 micros when [poly(dI-dC)]2 is the host. On the other hand, the host itself becomes a potent quenching agent when G[triple bond]C base pairs are present because of the reducing strength of guanine residues. | 18,811,150 |
Palladium-catalyzed amination of aryl and heteroaryl tosylates at room temperature. | Mild palladium-catalyzed aminations of aryl tosylates and the first aminations of heteroaryl tosylates are described. In the presence of the combination of L2Pd(0) (L = P(o-tol)3) and the hindered Josiphos ligand CyPF-t-Bu, a variety of primary alkylamines and arylamines react with both aryl and heteroaryl tosylates at room temperature to form the corresponding secondary arylamines in high yields with complete selectivity for the monoarylamine. These reactions at room temperature occur in many cases with catalyst loadings of 0.1 mol % and 0.01 mol % in one case, constituting the most efficient aminations of aryl tosylates by nearly 2 orders of magnitude. This catalyst is made practical by the development of a convenient method to synthesize the L2Pd(0) precursor. This complex is stable to air as a solid. In contrast to conventional relative rates for reactions of aryl sulfonates, the reactions of aryl tosylates are faster than parallel reactions of aryl triflates, and the reactions of aryl tosylates are faster than parallel or competitive reactions of aryl chlorides. | 18,811,161 |
Emission of volatile chemicals from flowering dogwood (cornus Florida L.) flowers. | Reproduction of flowering dogwood trees occurs via obligate out-crossing, and U.S. native bees have been suggested to be primary pollinators of this ecologically and economically important deciduous tree. Whether floral volatiles play a role in reproduction of the dogwood remains unclear. Objectives of this study were to identify principal volatile chemicals emitted from dogwood flowers and to assess a temporal volatile emission profile and volatile consistency across four cultivars. Inflorescences with intact bracts and 5 cm flower pedicel were removed from dogwood trees and subjected to headspace volatile collection. Six principal volatile compounds were detected from the flowers of the cultivar 'World's Fair' with 3-formylpyridine as the most abundant constituent. Subsequent headspace analyses performed using inflorescences without bracts or floral pedicels alone indicated that 3-formylpyridine, E-beta-ocimene, S-linalool, and ketoisophorone were mainly emitted from inflorescences. Experiments were also conducted to determine whether volatile emissions differed across time and between different cultivars of flowering dogwood. When volatile emission was analyzed for 48 h using 12 h light/dark cycles, the emission of several volatile compounds displayed diurnal patterns. Finally, whereas florets in inflorescences of four different dogwood cultivars emitted similar levels of the six principal floral volatile chemicals, 'Cherokee Brave' flowers alone yielded 4-methoxybenzaldehyde and germacrene-D. The implications of the findings of this study to dogwood breeding programs are discussed. | 18,811,168 |
Origins of the double asymmetric induction on proline-catalyzed aldol reactions. | Computational studies to elucidate the origin of the double asymmetric induction on proline-catalyzed aldol reaction have been performed using HF/6-31G(d) calculations. The computed transition structures explain the experimental data obtained. | 18,811,197 |
Alkaloids from the twigs of Daphniphyllum calycinum. | Twelve new alkaloids, caldaphnidines G-R (1-12), along with 24 known ones, were isolated from the twigs of Daphniphyllum calycinum. Their structures were elucidated by spectroscopic methods, especially two-dimensional NMR techniques. | 18,811,206 |
TAC-scaffolded tripeptides as artificial hydrolytic receptors: a combinatorial approach toward esterase mimics. | In this report, we present the first library of tripodal synthetic receptor molecules containing three different, temporarily N-terminal protected peptide arms capable of performing hydrolytic reactions. To construct this library, the orthogonally protected triazacyclophane (TAC)-scaffold was used in the preparation of a split-mix library of 19 683 resin bound tripodal receptor molecules. For the construction of the peptide arms, three different sets of amino acids were used, each focused on one part of the catalytic triad as found in several families of hydrolytic enzymes. Therefore, in the sets of amino acids used to assemble these tripeptides, basic (containing His and Lys), nucleophilic (containing Ser and Cys), or acidic (containing Asp and Glu) amino acid residues were present. In addition, nonfunctional hydrophobic amino acid residues were introduced. Possible unfavorable electrostatic interactions of charged N-termini or their acetylation during screening were circumvented by trifluoroacetylation of the N-terminal amines. Screening was performed with a known esterase substrate, 7-acetoxycoumarin, which upon hydrolysis gave the fluorescent 7-hydroxycoumarin, leading to fluorescence of beads containing a hydrolytically active synthetic receptor. Although many synthetic receptors contain catalytic triad combinations, apparently, only a few showed hydrolytic activity. Sequence analysis of the active receptors showed that carboxylate-containing amino acids are frequently found in the acidic arm and that substrate cleavage is mediated by lysine (noncatalytic) or histidine (catalytic) residues. Kinetic analysis of resynthesized receptors showed that catalysis depended on the number of histidine residues and was not assisted by significant substrate binding. | 18,811,207 |
One-by-one coupling of single defect centers in nanodiamonds to high-Q modes of an optical microresonator. | In this letter, we present the on-demand coupling of single NV(-) defect centers in nanodiamonds to a polystyrene microspherical resonator. From an ensemble on a coverslip, we select single nanodiamonds containing a single defect proven by a pronounced antibunching dip. With the help of a scanning near-field probe, we can attach these nanodiamonds to a microsphere resonator one-by-one. A clearly modulated fluorescence spectrum demonstrates coupling of the single defect centers to high-Q whispering-gallery modes. Our experiments establish a toolbox to assemble complex systems consisting of single quantum emitters and (coupled) microresonators. | 18,811,213 |
Synthesis of hybrid multicomponent disklike nanoparticles. | This manuscript describes the synthesis of a new generation of multicomponent disklike nanoparticles. In this work, we present for the first time, through the template-based sequential electrochemical deposition of metal/semiconductor/polymer segments, an innovative and effective method for preparing a wide range of metallic, semiconductor, and polymeric hybrid multicomponent disklike nanoparticles covering a wide and controlled dimension range from a few nanometers to hundreds of nanometers. Moreover, we can readily tailor the desired final size, aspect ratio, and composition of the disklike nanoparticles by varying the precursor material used and the electrochemical deposition approach. Furthermore, this simple route leads to a highly reproducible and high-throughput synthetic platform of new multicomponent and multifunctional nanoscale building blocks. | 18,811,214 |
Single- and two-species tests to study effects of the anthelmintics ivermectin and morantel and the coccidiostatic monensin on soil invertebrates. | Soil invertebrates in arable land are potentially exposed to veterinary medicines excreted by husbandry. The toxicity of three widely used pharmaceuticals was therefore investigated with the use of common soil invertebrates exposed in the laboratory in single- or two-species test system. The anthelmintic morantel did not cause significant mortality to either Folsomia fimetaria or Enchytraeus crypticus even at the highest tested concentration of 900 mg kg(-1) dry soil. The coccidiostatic monensin affected the reproduction of F. fimetaria and E. crypticus with soil concentrations estimated to cause a 10% effect at values of approximately 109 and 71.8 mg kg(-1) dry soil, respectively, but caused no mortality to adult. The anthelmintic ivermectin did not affect the survival of adult Hypoaspis aculeifer. Reproduction of H. aculeifer declined approximately 45% in response to ivermectin exposure of 5 mg kg(-1) dry soil. Ivermectin was highly toxic to F. fimetaria and affected the survival of adults with soil concentrations estimated to cause a 50% mortality at values of 5.3 mg kg(-1) dry soil in the single-species test system and 0.14 mg kg(-1) dry soil in the two-species test system. Reproduction of F. fimetaria was reduced by ivermectin with 10% effective concentration at 0.19 mg kg(-1) dry soil in the single-species test system and 0.02 mg kg(-1) dry soil in two-species test system. It was shown that species interactions may influence the response of test organisms to toxic substances. The data from this study and previously published data showed that, whereas ivermectin is likely to pose a risk to soil-dwelling invertebrates, adverse effects of morantel and monensin are unlikely to occur as a result of residue excretion from treated farm animals. | 18,811,226 |
Autophagy, an immunologic magic bullet: Mycobacterium tuberculosis phagosome maturation block and how to bypass it. | Mycobacterium tuberculosis is a facultative intracellular pathogen that parasitizes host macrophages where it persists in immature phagosomes by avoiding their maturation into phagolysosomes. The mechanisms of how M. tuberculosis inhibits phagolysosome biogenesis have been researched in detail and the maturation block at least partially depends on the manipulation of host phosphoinositide interconversions, with phosphatidylinositol 3-phosphate (PI3P) being a central target since it has been shown to be required for phagolysosome biogenesis. PI3P earmarks intracellular organelles for binding and assembly of effector molecules that interact with PI3P or its derivatives, including Class E Vps proteins such as Hrs and ESCRT components, early endosome antigen 1, which are required for sequential protein and membrane sorting within the endosomal and, by extension, phagosomal systems. In a search of a cellular mechanism that can bypass the tubercule bacillus-imposed PI3P block, researchers have uncovered a new general bactericidal process, autophagy, which can eliminate intracellular pathogens. This is a new, rapidly growing field replete with possibilities for novel, previously untried immunologic and pharmacologic interventions applicable not only to TB but to other stubborn bacterial, parasitic and viral diseases. | 18,811,236 |
Genetic algorithms with memory- and elitism-based immigrants in dynamic environments. | In recent years the genetic algorithm community has shown a growing interest in studying dynamic optimization problems. Several approaches have been devised. The random immigrants and memory schemes are two major ones. The random immigrants scheme addresses dynamic environments by maintaining the population diversity while the memory scheme aims to adapt genetic algorithms quickly to new environments by reusing historical information. This paper investigates a hybrid memory and random immigrants scheme, called memory-based immigrants, and a hybrid elitism and random immigrants scheme, called elitism-based immigrants, for genetic algorithms in dynamic environments. In these schemes, the best individual from memory or the elite from the previous generation is retrieved as the base to create immigrants into the population by mutation. This way, not only can diversity be maintained but it is done more efficiently to adapt genetic algorithms to the current environment. Based on a series of systematically constructed dynamic problems, experiments are carried out to compare genetic algorithms with the memory-based and elitism-based immigrants schemes against genetic algorithms with traditional memory and random immigrants schemes and a hybrid memory and multi-population scheme. The sensitivity analysis regarding some key parameters is also carried out. Experimental results show that the memory-based and elitism-based immigrants schemes efficiently improve the performance of genetic algorithms in dynamic environments. | 18,811,247 |
An empirically based model for latitudinal gradient in vole population dynamics. | Vole dynamics in northern Europe exhibit a well-defined geographical gradient, with oscillatory populations being confined to high latitudes. It has been proposed that oscillations in northern vole populations are driven by their interaction with specialist predators (weasels), while the more southern rodent populations are relatively stable because of regulation by generalist predators. We tested this generalist/specialist predation hypothesis by constructing an empirically based model for vole population dynamics, estimating its parameters, and making predictions about the quantitative pattern of the latitudinal shift in vole dynamics. Our results indicated that the model accurately predicted the latitudinal shift in the amplitude and periodicity of population fluctuations. Moreover, the model predicted that vole dynamics should shift from stable to chaotic as latitude is increased, a result in agreement with nonlinear time-series analysis of the data. The striking success of the model at predicting the shifts in amplitude and stability along the geographical gradient in northern Europe provides strong support for the key role of specialist and generalist predators in vole population dynamics. | 18,811,252 |
Does food web complexity eliminate trophic-level dynamics? | Investigators are always divided into those who are looking for rules and those who are looking for exceptions. (Hackett 1937, p. 106). | 18,811,260 |
Mutualism among safe, selfish sentinels: a dynamic game. | Sentinels are group members that watch from prominent positions. Sentinel interchanges often appear orderly, and groups with sentinels rarely have zero or many sentinels. A dynamic game was constructed to examine if these observations about sentinels could be based on selfish actions by individual group members. In this game, each group member chose to forage or be a sentinel based on its own energetic state and the actions of others. Sentinels received a selfish antipredator benefit if their ability to detect approaching predators more than compensated for their increased exposure to undetected predators. Provided sentinels were relatively safe and that detection information spread to other group members when sentinels detected predators, sentinels appeared highly coordinated for all combinations of parameters. This apparent coordination was based on mutualism because each individual gained by being a sentinel when other group members were not (and foraging when other group members were being sentinels). The model was very robust, but exact level of sentinel behavior varied somewhat with changes in foraging and predation parameters. This model could best be tested by testing its assumptions about sentinel safety, foraging-predation trade-offs, and information transfer in groups. | 18,811,295 |
Ecological biogeography of southern ocean islands: species-area relationships, human impacts, and conservation. | Previous studies have concluded that southern ocean islands are anomalous because past glacial extent and current temperature apparently explain most variance in their species richness. Here, the relationships between physical variables and species richness of vascular plants, insects, land and seabirds, and mammals were reexamined for these islands. Indigenous and introduced species were distinguished, and relationships between the latter and human occupancy variables were investigated. Most variance in indigenous species richness was explained by combinations of area and temperature (56%)-vascular plants; distance (nearest continent) and vascular plant species richness (75%)-insects; area and chlorophyll concentration (65%)-seabirds; and indigenous insect species richness and age (73%)-land birds. Indigenous insects and plants, along with distance (closest continent), explained most variance (70%) in introduced land bird species richness. A combination of area and temperature explained most variance in species richness of introduced vascular plants (73%), insects (69%), and mammals (69%). However, there was a strong relationship between area and number of human occupants. This suggested that larger islands attract more human occupants, increasing the risk of propagule transfer, while temperature increases the chance of propagule establishment. Consequently, human activities on these islands should be regulated more tightly. | 18,811,364 |
Sexual dimorphism in immune defense. | Sex differences in parasitism are common and may depend on sex differences in intensity of sexual competition, immunosuppression, or exposure to parasites. We used a large data set on the mass of two immune defense organs in birds (the bursa of Fabricius and the spleen) to test for consistent sex differences in immune defense. Males had a relative spleen mass that was consistently smaller, but more variable, than that of females across species of birds. A sex difference in the size of the spleen was not present among juveniles but was large and statistically significant among adults. The suppression of spleen mass in adult males increased with a measure of intensity of sexual selection: the frequency of extra-pair paternity. These findings suggest that sex differences in parasitism may arise as a consequence of sex differences in immune function, as mediated by sexual selection. | 18,811,367 |
Predator-mediated plasticity in morphology, life history, and behavior of Daphnia: the uncoupling of responses. | We studied the way 12 traits responded to fish kairomones in a set of 16 Daphnia magna clones derived from four different habitats-two where daphnids co-occur with fish and two without fish. These clones differed widely in their response to predator kairomones, with none of the clones showing a significant response in all traits and all clones showing a response for at least one trait. Most of the clones showed a significant response in one to four traits, with no evidence for an association between different traits. Clones from fish habitats were slightly more responsive to the presence of fish kairomones than clones from fishless locations. We conclude that most clones show an induced response to the presence of their predators (fish) but that there is a large genetic variability with respect to the traits for which clones show a response. Our results indicate that the major distinction is not between inducible and noninducible genotypes but rather that the genotypes differ in the combination of traits for which they show inducible responses. | 18,811,388 |
Competition in a group of equal foragers. | Using techniques from renewal process theory, we build a stochastic model for gain accumulation in a group of equal competitors foraging in a patchy environment. The model for gain of the individuals is based on the waiting times between subsequent prey encounters by the group. These waiting times depend on the number of foragers in the group. A single parameter of this dependency encompasses a variety of foraging scenarios, from co-operation to scramble. With constant patch size, correlations between gains of any pair of foragers are negative. This dependency is most intense in small groups. Increased variation in patch size makes correlations in gains between group members positive irrespective of the group size. For a solitary forager, variance in gain approaches zero with increasing time in the patch. For an individual member in a group, variance grows monotonically. Thus, depending on the patch departure rule controlling the time to be spent in the patch, solitary foragers may have a smaller variance in gain than members in a group. As solitary foragers also potentially harvest all prey in the patch, it is hard to believe that grouping behavior would evolve solely on the basis of foraging. | 18,811,402 |
Sexual conflict and the energetic costs of mating and mate choice in water striders. | Analyses of intersexual conflicts of interest over courtship, mating, or mate guarding require an understanding of the physiological costs of sexual interaction. Repeated respirometric measures of energetic expenditure were taken on female Aquarius remigis while unladen and while carrying a mating male, a small metal weight, or a euthanized male. Unladen "cruising" locomotion consumed an average of 334.6 microW of energy (82 J kg-1 m-1); this estimate of the cost of locomotion coincides with measures from voluntarily locomoting arthropods of similar mass and represents the first energetic measure of skating on a water surface. Cruising females carrying males or metal weights consumed 24% and 28% more energy than unladen females, respectively. Females engaged in "escape" locomotion consumed 43% more energy while carrying a male than while unladen. Further, our study shows that premating struggles, and therefore selective mating decisions, are energetically costly. Struggling females consumed an average of 936.6 microW, a 126% increase compared to cruising, nonstruggling females, and 64% more than mating females engaged in escape locomotion. We develop a quantitative model showing that at a certain harassment rate threshold, accepting superfluous matings becomes the "best of a bad job" for females. | 18,811,423 |
Reconciling classical and individual-based approaches in theoretical population ecology: a protocol for extracting population parameters from individual-based models. | The two main approaches in theoretical population ecology-the classical approach using differential equations and the approach using individual-based modeling-seem to be incompatible. Linked to these two approaches are two different timescales: population dynamics and behavior or physiology. Thus, the question of the relationship between classical and individual-based approaches is related to the question of the mutual relationship between processes on the population and the behavioral timescales. We present a simple protocol that allows the two different approaches to be reconciled by making explicit use of the fact that processes operating on two different timescales can be treated separately. Using an individual-based model of nomadic birds as an example, we extract the population growth rate by deactivating all demographic processes-in other words, the individuals behave but do not age, die, or reproduce. The growth rate closely matches the logistic growth rate for a wide range of parameters. The implications of this result and the conditions for applying the protocol to other individual-based models are discussed. Since in physics the technique of separating timescales is linked to some concepts of self-organization, we believe that the protocol will also help to develop concepts of self-organization in ecology. | 18,811,431 |
Within-brood competition and the optimal partitioning of parental investment. | In this article, we introduce a simple within-brood competitive growth model that maximizes parental fitness in unpredictable food conditions in species that exhibit parental care, progressive provisioning, and an initial brood overproduction. We argue that competition between siblings may provide a proximate mechanism for parents to adjust the number of surviving offspring or the social organization of the group in social species to food conditions. | 18,811,449 |
Chaos in the Pacific's coral reef bleaching cycle. | There is no simple explanation for the unusual increase in coral reef bleaching events that have been occurring on a global scale over the last 2 decades. Recent studies focusing on this problem reveal that mass bleaching events have a strong periodic component, arising every 3-4 yr in step with the El Niño climatic phenomenon. To explore this possibility further, we examine a simple oceanographic-ecological model designed to simulate the warm and cool phases of the Pacific Ocean cycle and gauge its effect on local coral reefs. This allows us to identify causes for localized 'hot spots' in the ocean, whose high sea surface temperatures have disastrous consequences for corals. The underlying wave dynamics of the model lead to chaotic oscillations (every 3-4 yr), which help explain the coexistence of both order and irregularity in the dynamics of mass bleaching. The model makes use of a temperature threshold mechanism-a bleaching event is triggered whenever temperature anomalies exceed a critical level. In a variable environment, the threshold mechanism is sensitive to background fluctuations, and their effects are studied by making use of a 'stochastic resonance' formulation. Global climate change and other trends in external background environmental conditions are all shown to strongly influence the distribution of mass coral bleaching events. | 18,811,451 |
A new look at relationships between size at maturity and asymptotic size. | Comparative studies have revealed positive correlations between size at maturity and asymptotic size in several taxa with asymptotic growth after maturity. Using a simple growth model, we show that positive correlations between size at maturity and asymptotic size are predicted for different individuals in the same species if growth costs of reproduction are inversely related to size at maturity. Several processes might lead to higher growth costs of reproduction for smaller individuals; these include effects of body size on competition for resources required for breeding, on the space available within the body cavity for food processing in gravid individuals, and on the costs of transporting eggs or young in relation to the total energy budget. We confirm several key elements of the growth model using data from female Iguana iguana lizards, including the novel assumption that instantaneous growth rates of adults of the same length will be positively related to their length at maturity. These analyses suggest a simple and possibly general explanation for positive correlations between size at maturity and asymptotic size within-and perhaps also among-species that continue to grow after maturity. | 18,811,453 |
Autoactivation of human ADAM8: a novel pre-processing step is required for catalytic activity. | Members of the ADAM (a disintegrin and metalloproteinase) family of proteins possess a multidomain architecture which permits functionalities as adhesion molecules, signalling intermediates and proteolytic enzymes. ADAM8 is found on immune cells and is induced by multiple pro-inflammatory stimuli suggesting a role in inflammation. Here we describe an activation mechanism for recombinant human ADAM8 that is independent from classical PC (pro-protein convertase)-mediated activation. N-terminal sequencing revealed that, unlike other ADAMs, ADAM8 undergoes pre-processing at Glu(158), which fractures the Pro (pro-segment)-domain before terminal activation takes place to remove the putative cysteine switch (Cys(167)). ADAM8 lacking the DIS (disintegrin) and/or CR (cysteine-rich) and EGF (epidermal growth factor) domains displayed impaired ability to complete this event. Thus pre-processing of the Pro-domain is co-ordinated by DIS and CR/EGF domains. Furthermore, by placing an EK (enterokinase) recognition motif between the Pro- and catalytic domains of multiple constructs, we were able to artificially remove the pro-segment prior to pre-processing. In the absence of pre-processing of the Pro-domain a marked decrease in specific activity was observed with the autoactivated enzyme, suggesting that the Pro-domain continued to associate and inhibit active enzyme. Thus, pre-processing of the Pro-domain of human ADAM8 is important for enzyme maturation by preventing re-association of the pro-segment with the catalytic domain. Given the observed necessity of DIS and CR/EGF for pre-processing, we conclude that these domains are crucial for the proper activation and maturation of human ADAM8. | 18,811,590 |
Similar expression of through-and-through fluid movement along orthograde apical plugs of MTA Bio and white Portland cement. | To compare the sealing ability of four hydraulic cements when used as an apical plug in teeth with wide-open apices. A sample of 70 maxillary central incisors were divided into four groups (n = 15) and a further 10 teeth served as controls. An artificial open apex was created in the teeth using Gates Glidden drills numbers 6-1 in a crown-down manner until the size 1 bur passed through the foramen. A divergent open apex was prepared to a size of 1.24 mm at the foramen by retrograde apical transportation using a number 8 (0.60) Profile Series 29 0.4 taper instrument inserted to the length of the cutting blade. In G1, the open apices were repaired with WMTA Angelus whilst in G2, G3 and G4 MTA Bio, Pro-Root MTA and Portland cement was employed respectively. Each root was assembled in a hermetic cell to allow the evaluation of fluid filtration. Leakage was measured by the movement of an air bubble travelling within a pipette connected to the teeth. Measurements of the air bubble movement were made after 10 min at a constant pressure of 50 cm H(2)O. The Kruskal-Wallis H-test was applied to the fluid flow data to detect differences between the experimental groups (P < 0.05). Fluid movement occurred in every sample but was variable in all the experimental groups, ranging from 0.61 to 2.45 microL min(-1). There was no significant difference in mean fluid flow between the experimental groups (P > 0.05). Fluid movement through teeth with open apices and filled with four hydraulic cements was similar. All cements allowed fluid movement. | 18,811,597 |
The IMPROVE study--a multinational, observational study in type 2 diabetes: baseline characteristics from eight national cohorts. | The IMPROVE study is a multinational, open-label, non-randomised, 26-week observational study assessing the safety and effectiveness of biphasic insulin aspart 30 (BIAsp 30) treatment in type 2 diabetes in routine clinical practice. The principal aims of this report were to characterise the baseline population and physicians' treatment decisions. Patients with type 2 diabetes who required insulin and whose physician had decided to initiate BIAsp 30 were eligible. At baseline, demographic data and detailed medical histories were collected and physicians recorded their reasons for starting BIAsp 30, the glycaemic targets set and the regimens chosen. Data from 51,286 patients were included in analyses. Baseline glycaemic control was poor in all eight countries in the present analysis and in all prestudy treatment groups [no therapy, oral antidiabetic drugs (OADs) only, insulin with or without OADs], and the rates of vascular complications were high. Although the management of each of the three main measures of glycaemic control were key reasons for starting BIAsp 30, target-setting for postprandial glucose levels was variable. A twice-daily regimen was used to start BIAsp 30 therapy for 80% or more of patients. The IMPROVE baseline data reaffirm the global nature of poor glycaemic control in type 2 diabetes and echo the concerns that initiation of therapy, particularly insulin, is commonly delayed in clinical practice. Although postprandial glucose control was a key driver for physicians' choice of BIAsp 30, this was not consistently reflected in the targets set. | 18,811,598 |
Risk factors for fracture following a fall among older people in residential care facilities in Australia. | To investigate which factors best predict whether a fall will result in a fracture. Prospective cohort. Residential care facilities. One thousand three hundred forty-two older men and women (mean age 86.0) who had a fall. Clinical risk factors and bone fragility by calcaneus broadband ultrasound attenuation (BUA) were assessed at baseline, and falls and fall-related fractures were recorded for up to 2 years. All fractures were validated using X-ray reports. During a median follow-up of 1.97 years, 6,646 falls resulted in 308 fractures. Fracture rates were 6.7, 4.8, and 3.1 per 100 falls for BUA in the lowest (10.5-39.7 dB/MHz), middle (39.8-58.9 dB/MHz), and highest (>/=58.9dB/MHz) tertiles, respectively. In multivariate analysis, the odds ratio for any fracture was 1.17 (95% confidence interval=1.08-1.27; P<.001) for every 10-dB/MHz reduction in BUA. Other significant risk factors in the model were lower weight, longer leg length, better balance, no severe cognitive impairment, intermediate care residence, lack of a history of falls in the previous year, and a history of fracture since age 50. For hip fracture, the only significant risk factors were lower weight, longer leg length, intermediate care residence, and lack of falls history. Important risk factors for whether a fracture occurs immediately after a fall include direct measures of bone fragility and a number of anthropometric and clinical factors that may increase or attenuate the mechanical impact of a fall. By identifying those at highest risk of fracture after a fall, these findings should have important implications for fracture prevention strategies. | 18,811,606 |
A manual of guidelines to score the modified cumulative illness rating scale and its validation in acute hospitalized elderly patients. | To update previous guidelines to score the Cumulative Illness Rating Scale (CIRS) and test their usefulness in hospitalized elderly patients. The CIRS was scored retrospectively in a cohort of elderly patients followed for 18 months. An acute internal medicine ward in an academic tertiary care hospital. Three hundred eighty-seven patients aged 65 and older. The CIRS was retrospectively scored for the enrolled patients. Intrarater and interrater reliability were calculated. Two illness severity indices (total score (TSC) and severity (SV)) and one comorbidity index (CM) were obtained. Clinical features and comprehensive geriatric assessment (CGA) variables were also used. All patients underwent an 18-month follow-up for mortality and rehospitalization. Intrarater and interrater reliability of the CIRS scored following the guidelines was good (intraclass correlation coefficients of 0.83 and 0.81, respectively). The TSC, SV, and CM correlated with clinical features (laboratory values, medication usage, and length of in-hospital stay) and CGA variables (cognitive impairment, depression and disability). All three indices were able to predict 18-month mortality and rehospitalization rates. This study confirmed the validity of the CIRS as an indicator of health status and demonstrated its ability to predict 18-month mortality and rehospitalization in hospitalized elderly patients. The availability of detailed guidelines for scoring the CIRS can improve its usefulness and facilitate more-widespread use for research and clinical aims. | 18,811,613 |
A new PTGDR promoter polymorphism in a population of children with asthma. | Recently, functional genetic variants of the PTGDR gene have been associated with asthma. The objective of this work was to study polymorphisms of the promoter region of PTGDR and their haplotype and diplotype combinations in a Spanish population of children with asthma. In this study, 200 Caucasian individuals were included. Asthma was specialist-physician diagnosed according to the ATS criteria. The polymorphisms were analyzed by direct sequencing. In the study, the new polymorphism (-613C > T) in the promoter region of PTGDR was analyzed. The CT genotype was more common in controls (17%) than in patients with asthma (1%) (p-value = 0.0003; OR, 0.057; 95% CI, 0.007-0.441). The CCCT CCCC diplotype (promoter positions -613, -549, -441, and -197) was more frequent in the group of patients with asthma [Fisher's p-value = 0.012; OR, 10.24; 95% CI (1.25-83.68)]; this diplotype is unambiguous. To our knowledge, this is the first study of -613C > T PTGDR polymorphism in patients. This analysis provides more complete information on influence of diplotype combinations of PTGDR polymorphisms in asthma. | 18,811,623 |
Vibrio cholerae non-O1 infection in cirrhotics: case report and literature review. | Vibrio species are ubiquitous in the marine environment and can cause severe infections in cirrhotic patients. Patients with liver disease should be warned about the potential dangers of consuming raw or undercooked seafood, and avoiding exposure of wounds to seawater. We report a case of severe sepsis from Vibrio cholerae non-O1 in a patient with cirrhosis awaiting orthotopic liver transplant. This case is aimed to advise clinicians about the importance of V. cholerae subtypes, and non-cholera Vibrio species infections in cirrhotic patients, highlighting the need to educate these patients to stay away from undercooked seafood. | 18,811,633 |
The consent and prescription compliance (COPRECO) study: does obtaining consent in the emergency department affect study results in a telephone follow-up study of medication compliance? | The objectives were to determine whether mandated research requirements for consent in the emergency department (ED) falsely distorts the results of a survey of patient-reported compliance with ED prescriptions and, in addition, to ascertain the level of patient compliance to medication instructions and find out the degree of displeasure expressed by patients called without prior consent. Patients given new prescriptions for a medicine to be taken regularly over a period of less than 30 days were eligible. A convenience sample of eligible patients was randomized to having consent obtained during their ED visit or at the time of telephone follow-up. Patients were called 7-10 days after their ED visit to determine their compliance with the prescription. Compliance rates between the two groups were compared, as was the prevalence of displeasure expressed by patients called without prior consent. Of 430 enrolled patients, 221 were randomized to receive ED consent for telephone follow-up, and 209 received telephone follow-up without prior ED consent. Telephone follow-up was successful in 318 patients (74%). The rate of noncompliance was slightly higher in the group without ED consent, 74/149 (50%; 95% confidence interval [CI] = 41% to 58%) than the group who gave ED consent for telephone follow-up, 67/169 (40%; 95% CI = 32% to 42%; p = 0.07). Among the two groups, 141/318 (44%) did not fill the prescription (n = 42) or took it incorrectly (n = 99). Only 1 (0.7%) of the 149 patients with successful telephone follow-up without prior ED consent expressed displeasure at this telephone call. Medicine noncompliance is a significant issue for patients discharged from the ED in this study. Although there was a trend toward greater compliance in patients who consented to the follow-up call, this did not reach statistical significance. ED patients do not object to receiving telephone follow-up for a research survey without giving prior consent. | 18,811,636 |
Role of menaquinone biosynthesis genes in selenate reduction by Enterobacter cloacae SLD1a-1 and Escherichia coli K12. | In this study, we investigated the role of menaquinone biosynthesis genes in selenate reduction by Enterobacter cloacae SLD1a-1 and Escherichia coli K12. A mini-Tn5 transposon mutant of E. cloacae SLD1a-1, designated as 4E6, was isolated that had lost the ability to reduce Se(VI) to Se(0). Genetic analysis of mutant strain 4E6 showed that the transposon was inserted within a menD gene among a menFDHBCE gene cluster that encodes for proteins required for menaquinone biosynthesis. A group of E. coli K12 strains with single mutations in the menF, menD, menC and menE genes were tested for loss of selenate reduction activity. The results showed that E. coli K12 carrying a deletion of either the menD, menC or menE gene was unable to reduce selenate. Complementation using wild-type sequences of the E. cloacae SLD1a-1 menFDHBCE sequence successfully restored the selenate reduction activity in mutant strain 4E6, and E. coli K12 menD and menE mutants. Selenate reduction activity in 4E6 was also restored by chemical complementation using the menaquinone precursor compound 1,4-dihydroxy-2-nathphoic acid. The results of this work suggest that menaquinones are an important source of electrons for the selenate reductase, and are required for selenate reduction activity in E. cloacae SLD1a-1 and E. coli K12. | 18,811,645 |
Nice natives and mean migrants: the evolution of dispersal-dependent social behaviour in viscous populations. | There has been much interest in the evolution of social behaviour in viscous populations. While low dispersal increases the relatedness of neighbours, which tends to promote the evolution of indiscriminate helping behaviour, it can also increase competition between neighbours, which tends to inhibit the evolution of helping and may even favour harming behaviour. In the simplest scenario, these two effects exactly cancel, so that dispersal rate has no impact on the evolution of helping or harming. Here, we show that dispersal rate does matter when individuals can adjust their social behaviour conditional on whether they have dispersed or whether they have remained close to their place of origin. We find that nondispersing individuals are weakly favoured to indiscriminately help their neighbours, whereas dispersing individuals are more readily favoured to indiscriminately harm their neighbours. | 18,811,663 |
Prevention of shedding and re-shedding of Toxoplasma gondii oocysts in experimentally infected cats treated with oral Clindamycin: a preliminary study. | This work aimed to evaluate the effects of preventive oral Clindamycin in cats infected with Toxoplasma gondii. Twelve short hair cats were divided into two groups (group 1 and group 2). No titres of T. gondii antibodies were detected in these cats before the experiment. The animals from group 1 were infected with tissue cysts of T. gondii and group 2 were infected and treated with Clindamycin (20 mg/kg/day). The infection was done with almost 40-50 tissue cysts for each cat on day 0. The cats from group 2 were treated with Clindamycin by oral rout for 24 days (from day -3 to day 21). At day 45, the groups 1 and 2 were divided into two subgroups with three animals each. Subgroups 1A and 2A were immunosuppressed with dexamethasone (1 mg/kg/day) for30 days and subgroups 1B and 2B were not immunosuppressed. Faecal exam looking for oocyst shedding was made by 30 days after T. gondii infection, and for 30 days after immunosuppression. All kittens from group 1 shedding oocysts after infection, while animals from group 2 did not shed. After immunosuppression period, all animals from group 1A re-shed oocysts and animals from group 2A remained without shed. However, 2 (66.6%) of the kittens from subgroup 2B shed oocysts 19-20 days after re-challenge. Based on this preliminary study, Clindamycin had a complete inhibitory effect on shedding of oocysts by cats, even under severe immunosuppression, which is a new finding not reported elsewhere. | 18,811,675 |
Mechanism of tyrosinase inhibition by deoxyArbutin and its second-generation derivatives. | Disorders, such as age spots, melasma and hyperpigmentation at sites of actinic damage, emanate from the augmentation of an increased amount of epidermal melanin. The ineptness of current therapies in treating these conditions, as well as high cytotoxicity, mutagenicity, poor skin penetration and low stability of skin-depigmenting formulations led us to investigate new compounds that meet the medical requirements for depigmentation agents. We have shown previously that the tyrosinase inhibitor deoxyArbutin (dA) is a more effective and less toxic skin lightener than hydroquinone (HQ). The efficacy and reversibility of dA and its derivatives on inhibiting tyrosine hydroxylase and DOPAoxidase was assessed using standard assays. dA and its second-generation derivatives inhibit tyrosine hydroxylase and DOPAoxidase activities of tyrosinase dose dependently thereby inhibiting melanin synthesis in intact melanocytes, when used at concentrations that retain 95% cell viability in culture. This depigmenting effect was completely reversible when the compounds were removed. Tyrosinase inhibition was also observed in vitro when tested using human and purified mushroom tyrosinase, establishing that they are direct enzyme inhibitors. Lineweaver-Burk reciprocal plot analysis using mushroom tyrosinase illustrated that dA and its derivatives are more robust competitive inhibitors than HQ, when tyrosine is used as substrate. Thus, dA and its second-generation derivatives, which inhibit melanogenesis at safe concentrations by specifically acting on the tyrosinase enzyme at a post-translational level, are promising agents to ameliorate hyperpigmented lesions or lighten skin. | 18,811,684 |
Identification of a previously unrecognized microdeletion syndrome of 16q11.2q12.2. | We report the identification of microdeletions of 16q11.2q12.2 by microarray-based comparative genomic hybridization (aCGH) in two individuals. The clinical features of these two individuals include hypotonia, gastroesophageal reflux, ear anomalies, and toe deformities. Other features include developmental delay, mental retardation, hypothyroidism, and seizures. The identification of common clinical features in these two individuals and those of one other report suggests microdeletion of 16q12.1q12.2 is a rare, emerging syndrome. These results illustrate that aCGH is particularly suited to identify rare chromosome abnormalities in patients with apparently non-syndromic idiopathic mental retardation and birth defects. | 18,811,697 |
Motor coordination difficulties and physical fitness of extremely-low-birthweight children. | Motor coordination difficulties and poor fitness exist in the extremely low birthweight (ELBW) population. This study investigated the relative impact of motor coordination on the fitness of ELBW children aged 11 to 13 years. One hundred and nine children were recruited to the study: 54 ELBW participants (mean age at assessment 12y 6mo; 31 male, 23 female; mean birthweight 769g, SD 148g; mean gestational age 26.6 weeks, SD 2.1 weeks) and 55 comparison children (mean age at assessment 12y 5mo; 28 males, 27 females; at least 37 weeks' gestation). All children completed the Movement Assessment Battery for Children (MABC), functional tests of postural stability and strength, growth measures, and tests of respiratory function. Maximal oxygen uptake (VO(2)max) was calculated from a 20m shuttle run test as a measure of fitness. The ELBW group had greater problems with postural stability (p=0.001) and motor coordination (p=0.001), with 70% rated as having a definite motor problem on the MABC brackets (those who scored less than the 5(th) centile on the MABC). The ELBW was also less fit than the comparison group (p=0.001), with 45% below the 10th centile for VO(2)max. There were differences between the groups for growth, strength, and particularly respiratory function. However, respiratory function did not significantly correlate with VO(2)max in the ELBW group. Motor coordination was the most powerful predictor of VO(2)max in both the ELBW (p=0.001) and the comparison groups (p=0.001). | 18,811,704 |
Waiting for child developmental and rehabilitation services: an overview of issues and needs. | Concern about the length of time that children, young people, and families may have to wait to access assessment, diagnostic, interventional, therapeutic, and supportive child developmental and rehabilitation (CDR) services is widespread, but adequate data collection and research on this issue remain limited. We review key concepts and issues relevant to waiting for CDR services from the published literature, a national workshop devoted to this topic, and international experience. We conclude that gaps in data, evidence, and consensus challenge our ability to address the issue of waiting for CDR services in a systematic way. A program of research coupled with actions based on consensus-building is required. Research priorities include acquiring evidence of the appropriateness and effectiveness of different models of intervention and rehabilitation services, and documenting the experience and expectations of waiting families. Consensus-building processes are critical to identify, categorize, and prioritize 'sentinel' components of CDR service pathways: (1) to reduce the inherent complexity of the field; (2) to create benchmarks for waiting for these respective services; and (3) to develop definitions for wait-time subcomponents in CDR services. Collection of accurate and replicable data on wait times for CDR services can be used to document baseline realities, to monitor and improve system performance, and to conduct comparative and analytic research in the field of CDR services. | 18,811,706 |
Identification and management of polyvascular disease in patients with noncardioembolic ischaemic stroke. | Recent registry results have shown that polyvascular disease (PolyVD), usually manifested as coronary heart disease or peripheral arterial disease (PAD), is a marker of increased morbidity and mortality in patients with noncardioembolic ischaemic stroke, but is often inadequately assessed. This Personal View Paper advocates routine examination for PolyVD in such patients. Peripheral arterial disease can be readily detected in routine practice by measurement of the ankle-brachial index. This paper makes recommendations for risk stratification, discharge documentation and, where possible, management of ischaemic stroke patients with PolyVD. | 18,811,739 |
Diagnostic accuracy of CT angiography in acute gastrointestinal bleeding. | The aim of the study was to carry out a systematic review determining the accuracy of CT angiography in the diagnosis of acute gastrointestinal bleeding. A search of published work in Medline and manual searching of reference lists of articles was conducted. Studies were included if they compared CT angiography to a reference standard of upper gastrointestinal endoscopy, colonoscopy, angiography or surgery in the diagnosis of acute gastrointestinal bleeding. Eight published studies evaluating 129 patients were included. Data were used to form 2 x 2 tables. Computed tomography angiography showed pooled sensitivity of 86% (95% confidence interval 78-92%) and specificity of 95% (95% confidence interval 76-100%), without showing significant heterogeneity (chi(2) = 3.5, P = 0.6) and (chi(2) = 5.4, P = 0.6), respectively. Summary receiver operating characteristic analysis showed an area under the curve of 0.93. Computed tomography angiography is accurate in the diagnosis of acute gastrointestinal bleeding and can show the precise location and aetiology of bleeding, thereby directing further management. Strong recommendations for use of CT cannot be made from this review because of the methodological limitations and further large prospective studies are needed to define the role of CT in acute gastrointestinal bleeding. | 18,811,756 |
Basal cell carcinoma of the nose: an Australian and New Zealand radiation oncology patterns-of-practice study. | Patients with a basal cell carcinoma (BCC) of the nose may be recommended radiotherapy (RT) with a wide variation in techniques and prescribed dose fractionation schedules between clinicians. The aim of this study was to ascertain variability in the patterns of practice among Australian and New Zealand radiation oncologists (ROs) when treating BCC arising on the nose. A postal survey was sent to 222 practising ANZ ROs detailing 12 different clinical scenarios of a BCC arising on the nose. The treatment selected for each scenario was analysed according to clinician's attitudes, training, experience and the availability of resources. The response rate was 74% (165/222) with 90 respondents treating non-melanoma skin cancer. Training was perceived to have a marked influence on treatment practice by most (79%). In total, 72% of ROs were 'very certain' in their choice of a dose fractionation schedule for obtaining local control and 61% for a satisfactory cosmetic outcome, respectively. Most (76%) favoured low-voltage photons over electrons as the optimal method of treatment, although for certain clinical scenarios most would use electrons. Dose fractionation schedules were highly variable with a lower total dose and hypofractionation favoured for older patients. Low-voltage photons were favoured for the T1 BCC and electrons for the T2 and T4 BCC. Nearly one-third of the ROs chose megavoltage photons for the T4 lesion. There is marked variation in treatment practices in terms of recommending RT over other treatment options, the choice of RT method, the dose fractionation schedule, the extent of field margins and the point of dose prescription. | 18,811,764 |
The parental experience of pregnancy after perinatal loss. | To review the research literature on the parental experience of pregnancy, primarily maternal, subsequent to perinatal loss. Computerized searches on CINAHL and PubMed databases. Articles from indexed journals relevant to the objective were reviewed from January 1997 to December 2007. Only research-based studies in English were included. The review was performed using the methodology of Whittemore and Knafl (2005). Data were extracted and organized under headings: author/year/setting; purpose; sample; design/instruments; results; and nursing implications for parents during a pregnancy following a perinatal loss. Depression and anxiety are frequently seen in pregnant women subsequent to a perinatal loss. The parental experience is filled with intense and conflicting emotions as parents balance being hopeful while worrying about another potential loss. It is important for health care providers to evaluate the woman's obstetric history, acknowledge and validate previous perinatal loss, and discuss with her what would be helpful during the prenatal period with respect to the previous perinatal loss. | 18,811,772 |
Percent body fat, skinfold thickness or body mass index for defining obesity or overweight, as a risk factor for asthma in schoolchildren: which one to use in epidemiological studies? | None of the epidemiological studies indicating that obesity is a risk factor for asthma in schoolchildren have used the percent body fat (PBF) to define obesity. The present study compares the definition of obesity using body mass index (BMI), PBF and the raw sum of the thickness of four skinfolds (SFT) to evaluate this condition as a risk factor for asthma. All classes of children of the target ages of 6-8 years of all schools in four municipalities of Murcia (Spain) were surveyed. Participation rate was 70.2% and the number of children included in the study was 931. Height, weight and SFT (biceps, triceps, subscapular and suprailiac) were measured according to standard procedures. Current active asthma was defined from several questions of the International Study of Asthma and Allergies in Childhood questionnaire. Obesity was defined using two standard cut-off points for BMI and PBF, and the 85th percentile for BMI, PBF and SFT. The highest quartile of each type of measurement was also compared with the lowest. A multiple logistic regression analysis was made for the various obesity definitions, adjusting for age, asthma in the mother and father and gender. The adjusted odds ratios of having asthma among obese children were different for boys and girls and varied across the different obesity definitions. For the standard cut-off points of BMI they were 1.19 [95% confidence interval (CI) 0.41-3.43] for girls and 2.00 (95% CI 0.97-4.10) for boys; however, for PBF (boys 25%, girls 30%) the corresponding figures were 1.54 (95% CI 0.63-3.73) and 1.20 (95% CI 0.66-2.21). BMI, PBF and SFT showed more consistency between each other when using the other cut-off points. BMI, PBF (except standard cut-off points) and SFT produce relatively comparable results when analysing the interaction between obesity and asthma. | 18,811,794 |
Ventricular arrhythmias after left ventricular assist device implantation. | Left ventricular assist devices (LVADs) have been used as a bridge to cardiac transplantation and as destination therapy in patients with advanced heart failure. The period after LVAD support is associated with ventricular arrhythmias (VAs) despite ventricular unloading and such VAs can have a detrimental effect on survival. Despite the increasing use of LVAD, little is known regarding post-LVAD VAs at the molecular level and in vivo. Forty-two patients who received LVAD over a 24-month period were evaluated and grouped on the basis of the presence or absence of VAs during LVAD support. We completed a comparative microarray analyses between six patients who developed ventricular tachycardia (VT) or ventricular fibrillation (VF) after LVAD support and six patients who did not develop VAs after LVAD. VAs occurred in 15 patients (35.7%) during LVAD support at a median post-LVAD day of 25.2. VAs were strongly associated with nonusage of a beta-blocker post-LVAD (odds ratio of 7.04, P-value = 0.001). Analysis of a subset of patients who had VT or VF after LVAD placement showed a decrease in the expression of connexin 43 (0.48 +/- 0.07), Na+/K+-ATPase (0.60 +/- 0.05), and voltage-gated K+ channel Kv4.3 (0.42 +/- 0.04), and an increase in Na+/Ca2+ exchanger (2.2 +/- 0.4) and the structural genes: Titin (2.1 +/- 0.2), laminin (1.7 +/- 0.4), calsequestrin (1.8 +/- 0.5), skeletal muscle isoform of troponin T (5.1 +/- 0.9), and skeletal muscle isoform of troponin I (3.9 +/- 0.7). After LVAD, the increased risk of VAs is strongly associated with nonusage of beta-blocker postoperatively. | 18,811,803 |
Focal AF-ablation after pulmonary vein isolation in a patient with hypertrophic cardiomyopathy using cryothermal energy. | A 42-year-old man, with a history of hypertrophic cardiomyopathy (HCM), an electrocardiogram pattern of ventricular preexcitation typical for mutations in the PRKAG2 gene, and highly symptomatic paroxysmal drug-resistant atrial fibrillation (AF), underwent successful circumferential isolation of his pulmonary veins using a 28-mm double lumen cryoballoon. Because AF was still inducible with programmed stimulation, fractionated signals were targeted in the left atrium with a conventional cryocatheter. Ablation of an endocardial focus with fractionated potentials at the base of the left appendage terminated the episode and rendered AF noninducible. No recurrence of AF was observed during a 10-month follow-up period. | 18,811,822 |
Paracetamol (Acetaminophen): mechanisms of action. | Paracetamol has a central analgesic effect that is mediated through activation of descending serotonergic pathways. Debate exists about its primary site of action, which may be inhibition of prostaglandin (PG) synthesis or through an active metabolite influencing cannabinoid receptors. Prostaglandin H(2) synthetase (PGHS) is the enzyme responsible for metabolism of arachidonic acid to the unstable PGH(2). The two major forms of this enzyme are the constitutive PGHS-1 and the inducible PGHS-2. PGHS comprises of two sites: a cyclooxygenase (COX) site and a peroxidase (POX) site. The conversion of arachidonic acid to PGG(2) is dependent on a tyrosine-385 radical at the COX site. Formation of a ferryl protoporphyrin IX radical cation from the reducing agent Fe(3+) at the POX site is essential for conversion of tyrosine-385 to its radical form. Paracetamol acts as a reducing cosubstrate on the POX site and lessens availability of the ferryl protoporphyrin IX radical cation. This effect can be reduced in the presence of hydroperoxide-generating lipoxygenase enzymes within the cell (peroxide tone) or by swamping the POX site with substrate such as PGG(2). Peroxide tone and swamping explain lack of peripheral analgesic effect, platelet effect, and anti-inflammatory effect by paracetamol. Alternatively, paracetamol effects may be mediated by an active metabolite (p-aminophenol). p-Aminophenol is conjugated with arachidonic acid by fatty acid amide hydrolase to form AM404. AM404 exerts effect through cannabinoid receptors. It may also work through PGHS, particularly in areas of the brain with high concentrations of fatty acid amide hydrolase. | 18,811,827 |
Non-invasive diagnostic evaluation of phototherapeutic effects of red light phototherapy of acne vulgaris. | During the past few years, various phototherapeutic protocols with full-spectrum visible light or selected wavebands have been investigated in the treatment of acne vulgaris with variable results. Fifteen women suffering from moderate acne vulgaris of the face were exposed to 20 J/cm(2) of broad-band red (lambda: 600-750 nm) light twice weekly for 4 weeks. In addition, with the aim to improve the present knowledge of the mechanisms of action of phototherapy, we measured skin sebum, pH, hydration and trans-epidermal water loss (TEWL). Lesions of the trunk were not irradiated and served as controls. A significant improvement of acne lesions and a significant decrease of skin sebum excretion and TEWL of the face were registered at the end of the therapy and at the 3-month follow-up visit. The results could be related to a reduced follicular colonization of Propionibacterium acnes, in that it was lethally damaged by photoactivated endogenous porphyrins. The present findings seem to indicate that red light phototherapy may represent an effective, well-tolerated, safe, simple and inexpensive treatment option for moderate acne vulgaris. | 18,811,865 |
Evaluation of sunscreen products using a reconstructed skin model exposed to simulated daily ultraviolet radiation: relevance of filtration profile and SPF value for daily photoprotection. | The recent definition of a standard daily ultraviolet radiation (DUVR) has allowed us to reproduce non-zenithal sun exposure conditions. Exposure to simulated DUVR induces biological damage in human skin, suggesting the need for an appropriate photoprotection. Sunscreen products were evaluated using human reconstructed skin in vitro. Two commercial sunscreens (A and B) having similar sun (burn) protection factor (SPF) values (approximately 15) but different profiles of transmission over the UVA range were tested on skin models exposed to increasing doses of DUVR. Another pair of sunscreens was also tested. One (product C) had an SPF approximately 18 with a well-balanced UVB-UVA profile and the other (product D) an SPF of approximately 27 with low UVA absorption. Biological parameters were assessed by (i) histology, (ii) vimentin immunostaining for dermal fibroblasts, and (iii) analysis of matrix metalloprotease (MMP)-1 secretion. Products A and C gave better protection from DUVR with regard to fibroblast alterations and MMP-1 release compared with products B and D, respectively. To ensure an efficient daily photoprotection from DUVR, the filtration profile of the product should be well balanced with a sufficient level of UVA absorption. With regard to end points evaluated in this study, our data suggest that a higher SPF value does not compensate for low UVA filtration. | 18,811,866 |
Bronchodilator reversibility, airway eosinophilia and anti-inflammatory effects of inhaled fluticasone in COPD are not related. | Bronchodilator reversibility (BDR) is common in smoking-related COPD, but the airway pathology underlying this has not been described. In particular, it is not known whether BDR is associated with underlying airway eosinophilia and whether BDR is predictive of a better response to inhaled corticosteroid (ICS) treatment. A double-blind, placebo-controlled, randomized 2:1 study of fluticasone propionate (FP), 500 microg twice daily versus placebo over 6 months was performed in subjects with mild to moderate COPD. Subjects with a clinical history of asthma were excluded, but not on BDR criteria alone. Induced sputum, BAL and endobronchial biopsies (EBB) were performed in 36 subjects at baseline, and 30 of these provided a second full set of samples (FP, n = 19; placebo, n = 11). Baseline BDR was not related to airway eosinophilia and did not predict response to ICS. Post-bronchodilator FEV(1) increased in the FP group compared with the placebo group (P = 0.05), and there were within-treatment group reductions in total symptom scores with FP (P < 0.05). Compared with placebo, FP reduced macrophage numbers but increased neutrophil numbers in EBB (P = 0.01 and P = 0.003, respectively). BAL neutrophil and epithelial cell numbers were also reduced with FP (P = 0.03 for both). There were within-treatment group reductions in the numbers of EBB mast cells and CD8+ve lymphocytes with FP (P = 0.007). BDR was not related to any particular inflammatory phenotype or any clinical or anti-inflammatory response to ICS in these subjects with mild to moderate COPD. | 18,811,878 |
Acylated ghrelin level in patients with OSA before and after nasal CPAP treatment. | Patients with newly diagnosed OSA have been reported to have recent weight gain prior to diagnosis. Ghrelin stimulates food intake and increases weight gain. Plasma ghrelin is decreased in obese and increased in lean individuals. Of the two circulating forms of ghrelin, acylated and unacylated, the former is thought to be essential for the biological activity of ghrelin. The plasma levels of the two forms of ghrelin were measured in 21 OSA patients (with a mean of 46.2 sleep-disordered events/h) before and after 1 month of nasal CPAP (nCPAP) treatment, and were compared with those in 14 untreated OSA patients and 13 individuals without OSA. The BMI was significantly higher in the 21 OSA patients than in the non-OSA group as were the baseline acylated (11.4 +/- 5.86 vs 7.19 +/- 3.80 fmol/mL, P = 0.03) and unacylated (84.2 +/- 50.6 vs 48.3 +/- 23.2 fmol/mL, P = 0.02) ghrelin levels. The total ghrelin level was positively correlated with the number of sleep-disordered breathings (P = 0.002). After 1 month of nCPAP treatment, the acylated ghrelin level significantly decreased (P = 0.02) while the unacylated ghrelin level did not (P = 0.09). Treatment of OSA may play an important role in the management of obesity in these patients by reducing the acylated ghrelin level. | 18,811,879 |
Limited role for outpatient parenteral antibiotic therapy for community-acquired pneumonia. | This study examined the potential utility of outpatient parenteral antibiotic therapy (OPAT) as a means of reducing the excessive number of patients hospitalized with low-risk community-acquired pneumonia (CAP). A prospective feasibility study was conducted, in which a selection algorithm was applied to a cohort of patients admitted with suspected CAP, to identify a group in whom admission may have been prevented by the use of OPAT. Numbers of potentially suitable patients, inpatient bed days saved and frequency of adverse events that may have led to readmission were measured. There were 118 inpatients treated with confirmed CAP during the study period, of whom 27 had low-risk disease (Pneumonia Severity Index grades I-III). Application of the selection algorithm identified eight (30% of those with low-risk disease) patients who were potentially suitable for OPAT, and this group commonly experienced adverse events during follow up which may have resulted in readmission to hospital. In many hospitalized patients with CAP, outpatient therapy is precluded by either disease severity or active medical and psychosocial factors. This limits the role of OPAT as a tool for reducing the inpatient burden of CAP. | 18,811,888 |
Evaluation of the risks of shedding Salmonellae and other potential pathogens by therapy dogs fed raw diets in Ontario and Alberta. | Dogs that participate in animal-assisted interventions (AAIs), often called 'therapy dogs', commonly interact with humans whose immune systems are not functioning optimally. The advisability of feeding raw meat (including poultry) to these animals remains a highly contentious issue, in spite of increasing evidence that raw meat is frequently contaminated with Salmonella. We set out to determine if consuming raw meat influences the risk of therapy dogs shedding Salmonella and other pathogens. Two hundred healthy therapy dogs from Ontario and Alberta were enrolled. Between May 2005 and November 2006, fecal specimens were collected from each dog every 2 months for 1 year, along with a log of places visited, antimicrobial use within the home, dog health status and diet. Specimens were cultured for Salmonella, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), extended-spectrum cephalosporinase (ESC) Escherichia coli and Clostridium difficile. Forty (20%) of the dogs were reported to have been fed raw meat at some point during the year. The incidence rate of Salmonella shedding in the raw meat-fed dogs was 0.61 cases/dog-year, compared with 0.08 cases/dog-year in dogs that were not fed raw meat (P<0.001). Controlling for therapy dog group, the repeated measures, and pig ear consumption and diarrhoea in the 2 months prior to specimen submission, dogs that consumed raw meat were significantly more likely to test positive for Salmonella at least once during the year than dogs that did not eat raw meat [odds ratio (OR) 22.7; 95% confidence interval (CI) 3.1-58.8; P<0.001]. Specific Salmonella serovars were more common among dogs that consumed raw meat versus those that did not include S. Typhimurium, S. Heidelberg and S. Kentucky. Raw meat consumption was also significantly associated with shedding ESC E. coli (OR 17.2; 95% CI 9.4-32.3). No associations between C. difficile, MRSA or VRE and consumption of raw meat were detected. We recommend that dogs fed raw meat should be excluded from AAI programmes, particularly when the programmes involve interaction with humans at high risk of infection or adverse sequelae attributable to infection. Furthermore, although AAI dogs may not be representative of the general population of dogs, we also recommend that feeding of raw meat to dogs is to be avoided in homes where immunocompromised people live. | 18,811,908 |
Reversal of benign prostate hyperplasia by selective occlusion of impaired venous drainage in the male reproductive system: novel mechanism, new treatment. | The prostate is an androgen-regulated exocrine gland producing over 30% of the noncellular components of the semen and promoting optimal conditions for survival and motility of sperm in the vagina. Benign prostate hyperplasia (BPH) is the most common benign neoplasm in men. Its aetiology is not clear, and therefore, current medical treatments are directed towards the symptoms. Though testosterone is known to be the promoter of prostate cell proliferation, no causal relation between serum testosterone levels and BPH has been found. In this study, we propose a novel and tested pathophysiological mechanism for the evolution of BPH and suggest a tested and effective treatment. We found that in all BPH patients, the one-way valves in the vertically oriented internal spermatic veins are destroyed (clinically manifested as varicocele), causing elevated hydrostatic pressure, some 6-fold greater than normal, in the venous drainage of the male reproductive system. The elevated pressure propagates to all interconnected vessels leading to a unique biological phenomenon: venous blood flows retrograde from the higher pressure in the testicular venous drainage system to the low pressure in the prostatic drainage system directly to the prostate (law of communicating vessels). We have found that free testosterone levels in this blood are markedly elevated, with a concentration of some 130-fold above serum level. Consequently, the prostate is exposed to: (i) increased venous pressure that causes hypertrophy; (ii) elevated concentration of free testosterone causing hyperplasia. We have treated 28 BPH patients using a technique that restores normal pressure in the venous drainage in the male reproductive system. The back-pressure and the back-flow of blood from the testicular to the prostate drainage system were eliminated and, consequently, a rapid reduction in prostate volume and a regression of prostate symptoms took place. | 18,811,916 |
Decline of plasma 5alpha-dihydrotestosterone (DHT) levels upon testosterone administration to elderly men with subnormal plasma testosterone and high DHT levels. | The study was performed to measure the impact of testosterone (T) administration on circulating levels of 5alpha-dihydrotestosterone (DHT). Group 1 (32 men; mean age 61 years; mean T 6.9 +/- 1.9 nmol l(-1)) were treated for 15 months with long-acting T undecanoate. Group 2 (23 men, mean age 60 years, mean T 7.6 +/- 2.0 nmol l(-1)) were treated for 9 months with T gel. Plasma T and DHT were measured before and after 9 months T administration. In the men treated with T undecanoate plasma T and DHT were also measured after 12 and 15 months. Before T administration, plasma DHT ranged from 0.39 to 1.76 nmol l(-1) (0.30-1.90 nmol l(-1)). Mean DHT declined upon T administration from 0.95 +/- 0.50 to 0.55 +/- 0.30 nmol l(-1) (P < 0.05). With an arbitrary cut-off at 0.60 nmol l(-1), all 21 values of DHT > 0.60 nmol l(-1) had fallen from 1.29 +/- 0.50 to 0.70 +/- 0.60 nmol l(-1) (P < 0.01). Below this cut-off point 13 values rose and 21 fell upon T administration. Below this cut-off point values on average declined from 0.39 +/- 0.12 to 0.30 +/- 0.14 nmol l(-1) (P < 0.05). The study revealed that in a cohort of elderly men with subnormal plasma T levels plasma DHT levels declined upon T administration when they were in the higher range of normal (>0.6 nmol l(-1)), with a profound shift of DHT/T ratios presumed to be an indicator of a reduced 5alpha-reductase activity. Below plasma DHT levels of 0.6 nmol l(-1), responses of plasma DHT to T administration varied. | 18,811,920 |
Effect of repeated sequential ejaculation on sperm DNA integrity in subfertile males with asthenozoospermia. | The aim of this work was to study the possible beneficial effect of repeated sequential ejaculation on sperm DNA integrity in subfertile males and its possible implementation in assisted reproduction. The study included 20 infertile males with idiopathic asthenozoospermia or oligoasthenozoospermia. They underwent detailed history taking, complete clinical assessment and hormonal assessment. Patients were asked to bring two semen samples (taken within 1-3 h). Two consecutive samples were assessed with regard to semen volume, sperm count, motility grading, and morphology and sperm DNA integrity using the comet assay. There was a significant improvement in the sperm motility pattern and DNA integrity in the second sample in comparison with the first sample. Therefore, it is concluded that due to its positive impact on sperm motility and DNA integrity, repeated sequential ejaculation is recommended in subfertile males with idiopathic asthenozoospermia who pursue assisted reproduction. | 18,811,922 |
SSMap: a new UniProt-PDB mapping resource for the curation of structural-related information in the UniProt/Swiss-Prot Knowledgebase. | Sequences and structures provide valuable complementary information on protein features and functions. However, it is not always straightforward for users to gather information concurrently from the sequence and structure levels. The UniProt knowledgebase (UniProtKB) strives to help users on this undertaking by providing complete cross-references to Protein Data Bank (PDB) as well as coherent feature annotation using available structural information. In this study, SSMap - a new UniProt-PDB residue-residue level mapping - was generated. The primary objective of this mapping is not only to facilitate the two tasks mentioned above, but also to palliate a number of shortcomings of existent mappings. SSMap is the first isoform sequence-specific mapping resource and is up-to-date for UniProtKB annotation tasks. The method employed by SSMap differs from the other mapping resources in that it stresses on the correct reconstruction of the PDB sequence from structures, and on the correct attribution of a UniProtKB entry to each PDB chain by using a series of post-processing steps. SSMap was compared to other existing mapping resources in terms of the correctness of the attribution of PDB chains to UniProtKB entries, and of the quality of the pairwise alignments supporting the residue-residue mapping. It was found that SSMap shared about 80% of the mappings with other mapping sources. New and alternative mappings proposed by SSMap were mostly good as assessed by manual verification of data subsets. As for local pairwise alignments, it was shown that major discrepancies (both in terms of alignment lengths and boundaries), when present, were often due to differences in methodologies used for the mappings. SSMap provides an independent, good quality UniProt-PDB mapping. The systematic comparison conducted in this study allows the further identification of general problems in UniProt-PDB mappings so that both the coverage and the quality of the mappings can be systematically improved for the benefit of the scientific community. SSMap mapping is currently used to provide PDB cross-references in UniProtKB. | 18,811,932 |
A comparison of EQ-5D index scores using the UK, US, and Japan preference weights in a Thai sample with type 2 diabetes. | Data are scarce on the comparison of EQ-5D index scores using the UK, US, and Japan preference weights in other populations. This study was aimed to examine the differences and agreements between these three weights, psychometric properties including test-retest reliability, convergent and known-groups validity, and the impact of differences in the EQ-5D scores on the outcome of cost-utility analysis in Thai people. A convenience sample of 303 type 2 diabetic outpatients (18 years or older) from a cross-sectional study was examined. ANOVA and pos-hoc Bonferroni tests were used to determine the differences among the three EQ-5D scores. The agreements among the EQ-5D scores were assessed employing intraclass correlations coefficients (ICCs) and Bland-Altman plots. The ICCs were utilized to examine the test-retest reliability. Spearman's rho correlation coefficients were used to assess the convergent validity between the EQ-5D scores and sociodemographic & clinical data, and health status. Mann-Whitney U tests were used to test the differences in EQ-5D scores between the known groups including HbA1c level (cut point of 7%), and the presence of diabetic complications namely neuropathy, retinopathy, nephropathy and cardiovascular diseases. Seven hypothetical decision trees were created to evaluate the impact of differences in the EQ-5D scores on the incremental cost-utility ratio (ICUR). The US weights yielded higher scores than those of the UK and the Japan weights (p < 0.001, both), while the UK and the Japan weighted scores did not differ (p > 0.05). Both UK and US scores had more agreement with each other than with the Japan scores. Regarding psychometric properties, the Japan scheme provided better test-retest reliability, convergent and known-groups validity than both UK and US schemes. The variation in EQ-5D scores estimated from UK, US, and Japan preference weights had a marginal impact on ICUR (range: 1.23-6.32%). Since the Japan model showed more preferable psychometric properties than the UK and the US models and the differences in these EQ-5D scores had a small impact on ICUR, we recommended that for both clinical and policy purposes the Japan scheme should be used in Thai people. However, more research needs to be done. | 18,811,935 |
Passive administration of monoclonal antibodies to anthrolysin O prolong survival in mice lethally infected with Bacillus anthracis. | Bacillus anthracis has two major virulence factors: a tripartite toxin that produces lethal and edema toxins and a polyglutamic acid capsule. A recent report suggested that a toxin belonging to the cholesterol dependent cytolysin (CDC) family, anthrolysin O (ALO) was a new virulence factor for B. anthracis but subsequent studies have questioned its relevance in pathogenesis. In this study, we examined the immunogenicity of recombinant anthrolysin O (rALO) in mice. BALB/c mice immunized with rALO and boosted after two weeks, produce sera with strong Ab responses with a predominance of IgG1 and IgG2a. Five hybridomas to rALO were recovered representing the IgM, IgG1, and IgG2b isotypes. Passive administration of 3 of the five monoclonal antibodies (mAbs) to rALO prior to infection with lethal intravenous (i.v.) B. anthracis Sterne strain infection in mice was associated with enhanced average survival and a greater likelihood of surviving infection. A combination of two mAbs to ALO was more effective than either mAb separately. One mAb (64F8) slowed the toxicity of rALO for J774.16 macrophage-like cells. Our results suggest that ALO contributes to the virulence of B. anthracis Sterne strain in this infection model and that Ab response to ALO may contribute to protection in certain circumstances. | 18,811,967 |
The purpose, composition, and function of an institutional review board: balancing priorities. | The institutional review board (IRB) is one part of the research enterprise designated to protect human subjects. At times the IRB can feel like an oppressive oversight body bound by regulations and designed to inhibit research. However, in reality the IRB was an attempt by the federal government to streamline a variety of processes to ensure the protection of human subjects. Growing out of a history of unethical scientific research, the principle goal of the IRB is to protect human subjects. At some institutions the IRB has an additional role, to take a second look at proposed scientific methods to ensure the highest quality research. The legal basis, purpose, composition, and function of an IRB, and potential challenges in human-subjects research are reviewed here. | 18,811,996 |
Induction of immunity in sheep to Fasciola hepatica with mimotopes of cathepsin L selected from a phage display library. | An M13 phage random 12-mers peptide library was used to screen cathepsin L mimotopes of Fasciola hepatica and to evaluate their immunogenicity in sheep. Seven clones showed positive reactivity to a rabbit anti-cathepsin L1/L2 antiserum in ELISA, and their amino acid sequences deduced by DNA sequencing were tentatively mapped on the protein. Twenty sheep were randomly allocated into 4 groups of 5 animals each, for immunization with 1x10(14) phage particles of clones 1, 20, a mixture of 7 clones and PBS, without adjuvant at the beginning, and 4 weeks later. All groups were challenged with 300 metacercariae at week 6 and slaughtered 16 weeks later. The mean worm burdens after challenge were reduced by 47.61% and 33.91% in sheep vaccinated with clones 1 and 20, respectively; no effect was observed in animals inoculated with the clone mixture. Also, a significant reduction in worm size and burden was observed for those sheep immunized with clone 1. Animals receiving clone 20, showed a significant reduction in egg output. Immunization induced a reduction of egg viability ranging from 58.92 to 82.11%. Furthermore, vaccinated animals produced clone-specific antibodies which were boosted after challenge with metacercariae of F. hepatica. | 18,812,010 |
Suppressive potencies of calcineurin inhibitors against the mitogen-induced blastogenesis of peripheral-blood mononuclear cells of myasthenia gravis patients. | The calcineurin inhibitors, tacrolimus and ciclosporin, are two useful immunosuppressive drugs for the treatment of myasthenia gravis (MG), for patients who have low responses to glucocorticoids. We have studied the suppressive potencies of tacrolimus and ciclosporin on concanavalin A-induced blastogenesis of peripheral-blood mononuclear cells (PBMCs) obtained from 38 MG patients and 26 healthy volunteers. Differences in the IC50 values of the two calcineurin inhibitors between the patients and the healthy subjects were evaluated. The median (range) IC50 values for tacrolimus and ciclosporin on the blastogenesis of PBMCs of MG patients were 0.06 (0.001-100) and 0.41 (0.09-83.0) ng mL(-1), respectively. In contrast, the median (range) IC50 values of tacrolimus and ciclosporin on healthy PBMCs were 0.16 (0.001-0.33) and 5.59 (1.4-31.3), respectively, and thus ciclosporin potencies against PBMCs of MG patients were significantly higher than those against PBMCs of healthy subjects (P < 0.0001). The differences in tacrolimus IC50 values between the patients and healthy subjects were not significant. There was a correlation between ciclosporin IC50 values against the blastogenesis of PBMCs of MG patients and the duration of the disease (r = 0.35, P = 0.049). A significant correlation between the IC50 values of ciclosporin and those of prednisolone against the blastogenesis of PBMCs of MG patients was also observed (r = 0.56, P = 0.003). Furthermore, the ciclosporin IC50 values significantly correlated with the periods of glucocorticoid administration for MG treatment (r = 0.42, P = 0.038). Such correlations were not observed with the tacrolimus IC50 values. These results suggested that glucocorticoid administration had an influence on PBMC response to the suppressive efficacy of ciclosporin in MG. | 18,812,027 |
Effect of hesperetin, a citrus flavonoid, on bacterial enzymes and carcinogen-induced aberrant crypt foci in colon cancer rats: a dose-dependent study. | Hesperetin, an important bioactive compound in Chinese traditional medicine, has antioxidant and anticarcinogenic properties. Hesperetin is found in abundance in orange and grape juices (200-590 mg L(-1)) consumed in the daily diet. We have investigated the effect of different doses of hesperetin on faecal and colonic mucosal bacterial enzymes and aberrant crypt foci (ACF) in 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis in male Wistar rats. The rats were divided into six groups and were fed a modified pellet diet for 16 weeks. Group 1 served as control and group 2 received the modified pellet diet along with hesperetin (30 mg kg(-1)). The rats in groups 3-6 rats were given a weekly subcutaneous injection of DMH (20 mg kg(-1)) for the first four weeks. Hesperetin was supplemented orally at different doses (10, 20 or 30 mg kg(-1)) for a total of 16 weeks. At the end of the experimental period all rats were killed. In DMH-treated rats, the activity of faecal and colonic mucosal bacterial enzymes, such as beta-glucuronidase, beta-galactosidase, beta-glucosidase, nitroreductase, sulfatase and mucinase, were significantly elevated, but in rats supplemented hesperetin along with DMH the activity was significantly lowered (P < 0.05). The total number of aberrant crypts was significantly increased in unsupplemented DMH-treated rats, while hesperetin supplementation to DMH-treated rats significantly reduced the total number of crypts. The results demonstrated that hesperetin supplementation at a dose of 20 mg kg(-1) played a potent role in suppressing the formation of aberrant crypt foci and reducing the activity of bacterial enzymes in colon cancer. | 18,812,032 |
Genetic diversity in clinical Mycobacterium tuberculosis isolates from Punjab. | Two hospitals, Sri Guru Ram Das Institute of Medical Sciences and Research and the TB and Chest Hospital, Amritsar, Punjab. To explore genetic diversity among the clinical Mycobacterium tuberculosis isolates prevalent in Punjab. Fifty-six random clinical isolates of M. tuberculosis were cultured from the sputum specimens of pulmonary tuberculosis patients. DNA was extracted from cultured biomass and analysed using the mycobacterial interspersed repetitive units (MIRU) typing method. MIRU typing of 51 isolates revealed 45 different patterns, with a combined Hunter-Gaston discriminatory index (HGDI) of 0.990. Five clinical isolates failed to amplify for one or more MIRUs and were excluded from the analysis. The remaining isolates were categorised in three groups based on the allelic heterogeneity of individual MIRUs. MIRU 10, 16, 26 and 31 were highly discriminant, with an HGDI value >0.6; MIRU 4, 23, 24, 39 and 40 were designated as moderately discriminant (HGDI value 0.6-0.3) and MIRU 2, 20 and 27 were poorly discriminant (HGDI value <0.3). MIRU typing and the HGDI values revealed that M. tuberculosis strains from Punjab are genetically quite heterogeneous. | 18,812,040 |
The epidemiology of tuberculosis in Ottawa, Canada, 1995-2004. | In Ottawa (population 774,072), active tuberculosis (TB) cases are reported to Ottawa Public Health. There has been no comprehensive local epidemiological analysis to date. We report the epidemiology of TB in Ottawa and identify areas of improvement. We reviewed TB cases reported to the Reportable Disease Information System from 1995 to 2004 to determine epidemiological characteristics, drug resistance, use of directly observed treatment (DOT) and rates of human immunodeficiency virus (HIV) co-infection. A total of 584 TB cases (79% foreign-born) were analyzed (average annual incidence 7.5/100,000). Anatomical site of disease followed national trends, with 58% being pulmonary TB. DOT was applied in 49% of total cases. Culture results were available for 385 (66%) and resistance was found in 46 (12%) cases. HIV testing results were available for only 139 cases: 24% were positive. Overall, Ottawa TB rates are slightly higher than national rates, yet they reflect national trends. The surveillance data were imperfect, with poor or no recording of aboriginal origin, adverse events and treatment outcomes. Reported resistance patterns may be underestimated, as only 66% had cultures. HIV testing was underutilized. Given the high mortality with TB-HIV co-infection, testing should be routine. Correcting these limitations will improve surveillance data and TB control in the future. | 18,812,041 |
Treatment outcome and follow-up of multidrug-resistant tuberculosis patients, West Coast/Winelands, South Africa, 1992-2002. | Brooklyn Chest Hospital, Western Cape, South Africa. To evaluate the treatment outcome and 2- and 5-year follow-up of patients treated for multidrug-resistant tuberculosis (MDR-TB) with individualized regimens. Retrospective cohort study of all MDR-TB patients starting treatment during 1992-2002. Patients were evaluated every 6 months for 2 years after treatment and at 5 years when possible. Over 11 years, 491 (66%) of 747 MDR-TB patients received treatment with two or more second-line drugs; 239 (49%) were cured or completed treatment, 68 (14%) died, 144 (29%) defaulted from treatment, 27 (5%) failed, 10 (2%) transferred out and 3 (<1%) remained on treatment. Only 176 (36%) were tested for human immunodeficiency virus and 15 were positive. The proportion with a successful MDR-TB treatment outcome declined over time, while the proportion who defaulted remained stable. Among 410 patients who had not transferred out or died, 281 (69%) had 2-year data available: 185 (66%) were cured or completed treatment, 32 (11%) were retreated for TB and 64 (23%) died. Under program conditions in the West Coast/Winelands District, default rates were high and treatment success rates low. Outreach strategies for MDR-TB treatment should only be implemented if adequate resources are committed to the program. | 18,812,049 |
Costs and cost-effectiveness of tuberculosis cultures using solid and liquid media in a developing country. | The expansion of culture has been proposed to aid tuberculosis (TB) control in developing countries. To examine the cost and cost-effectiveness at the Zambian National TB Reference Laboratory of homemade and commercially produced Löwenstein-Jensen culture (HLJ and CLJ) as well as automated and manually read liquid culture (AMGIT and MMGIT). Costs were estimated from the provider's perspective and based on the average monthly throughput. Cost-effectiveness estimates were based on yield during the study period. All techniques show comparable costs per culture (between US$28 and $32). Costs per Mycobacterium tuberculosis specimen detected were respectively US$197, $202, $312 and $340 for MMGIT, AMGIT, CLJ and HLJ. When modelled for the maximum throughput, costs were above US$95 per M. tuberculosis specimen detected for all techniques. When only performed among smear-negative specimens, costs per additionally identified M. tuberculosis would be US$487 for MMGIT and higher for other methods. Based on cost-effectiveness grounds, liquid media compare well with conventional solid media, especially where yield of MGIT is substantially higher than that of LJ media. The results indicate high overall costs per culture; the expansion of culture to decentralised levels with lower throughputs may result in even higher costs. | 18,812,051 |
Motor proteins: myosin mechanosensors. | Mechanosensation is emerging as a general principle of myosin motors. As demonstrated in a recent study, the single-headed myosin I molecule is an exquisite mechanosensor, able to sense strain over a very small force range. | 18,812,080 |
Behavioural genetics: the social fly. | Two studies report the presence of a social influence on pheromonal communication in fruit flies, demonstrating that the production of pheromone blends and mating behaviour are profoundly influenced by social context. | 18,812,081 |
Sporulation: SpoIIIE is the key to cell differentiation. | Sporulation in Bacillus subtilis requires asymmetric cell division, chromosome transfer into the spore and establishment of differential gene expression patterns. Several recent studies highlight the key roles of the SpoIIIE motor in this process. | 18,812,085 |
Combined phacoemulsification and transpupillary removal of heavy silicone oil. | We describe a technique for heavy silicone oil removal combined with phacoemulsification and intraocular lens insertion without scleral incisions or sutures using a modified 16-gauge cannula. The technique is less invasive than other techniques for removing silicone oil and does not interfere with the uveal tract or the peripheral retina. | 18,812,112 |
Corneal wavefront-guided photorefractive keratectomy in patients with irregular corneas after corneal refractive surgery. | To evaluate the corrective potential of corneal wavefront-guided photorefractive keratectomy (PRK) in patients with high levels of corneal aberrations and symptoms after previous corneal refractive surgery. Vissum-Instituto de Oftalmológico de Alicante, Alicante, Spain. This study comprised 25 eyes (20 patients) that had 1 or more previous unsuccessful keratorefractive procedure. All eyes had PRK retreatment using the Esiris excimer laser and ORK-CAM software for customized ablation design. All eyes had a high preoperative level of corneal higher-order aberrations (HOAs) (coma-like or spherical-like root mean square [RMS] >0.5 microm). Changes in refractive outcomes, subjective symptoms, and corneal aberrometry were evaluated during a 6-month follow-up. Uncorrected visual acuity improved significantly from preoperatively (mean 0.48) to 6 months after retreatment (mean 0.75) (P<.01). The mean best spectacle-corrected visual acuity (BSCVA) also improved significantly, from 0.78 to 0.90, respectively (P<.01). Forty-four percent of patients gained 1 or more lines of BSCVA. The reduction in cylinder at 6 months was statistically significant (P= .01). Corneal aberrometry at 6 months showed a statistically significant reduction in total (P= .01), spherical-like (P<.01), coma-like (P= .02), and primary coma (P<.01) RMS. At 6 months, 72% of patients had low or no perception of halos and all reported no glare. Corneal wavefront-guided PRK enhancement with the ORK-CAM system minimized corneal HOAs in eyes with previous unsuccessful keratorefractive surgery. | 18,812,125 |
Methicillin-resistant Staphylococcus aureus endophthalmitis after phacoemulsification in a continuous ambulatory peritoneal dialysis patient. | We report a case of methicillin-resistant Staphylococcus aureus (MRSA) endophthalmitis after phacoemulsification in a continuous ambulatory peritoneal dialysis (CAPD) patient with a history of MRSA infection. This case raised the problem of preoperative identification and subsequent management of MRSA carrier status, which might reduce the risk for sight- or life-threatening infection. | 18,812,138 |
ACR Appropriateness Criteria on Hodgkin's lymphoma: favorable prognosis stage I and II. | The treatment for favorable-prognosis stage I and II Hodgkin's lymphoma has evolved over the past several years. Studies have attempted to reduce long-term treatment-related side effects, such as second malignancies and cardiac toxicity, through reduced chemotherapy or reduced radiotherapy. Randomized trials have compared radiation therapy alone with combined-modality therapy (chemotherapy followed by involved-field radiotherapy). Recent and ongoing trials have evaluated the optimal regimen and number of cycles of chemotherapy and the optimal radiotherapy dose and field size as part of combined-modality therapy, as well as the elimination of radiation therapy. Combined-modality therapy represents the current standard of care for most patients with favorable-prognosis early-stage Hodgkin's lymphoma. Chemotherapy alone could also be an option for selected patients who are at low risk for relapse and high risk for late effects from radiotherapy. This article reviews recent and ongoing studies on treatment for favorable-prognosis early stage Hodgkin's lymphoma. Representative clinical cases are presented, with treatment recommendations from an expert panel of radiation oncologists and medical oncologists. | 18,812,149 |
MUC1 intra-cellular trafficking is clathrin, dynamin, and rab5 dependent. | MUC1, a transmembrane glycoprotein, is abnormally over-expressed in most human adenocarcinomas. MUC1 association with cytoplasmic cell signal regulators and nuclear accumulation are important for its tumor related activities. Little is known about how MUC1 translocates from the cell membrane to the cytoplasm. In this study, live cell imaging was used to study MUC1 intracellular trafficking. The interaction between EGFR and MUC1 was mapped by FRET analysis and EGF stimulated MUC1 endocytosis was observed directly through live cell imaging. MUC1-CT endocytosis was clathrin and dynamin dependent. Rab5 over-expression resulted in decreased cell membrane localization of MUC1, with accumulation of MUC1 endocytic vesicles in the peri-nuclear region. Conversely, over-expression of a Rab5 dominant negative mutant (S34N) resulted in redistribution of MUC1 from the peri-nuclear region to the cytoplasm. Collectively, these results indicated that MUC1 intra-cellular trafficking occurs through a regulated process that was stimulated by direct EGFR and MUC1 interaction, mediated by clathrin coated pits that were dynamin dependent and regulated by Rab5. | 18,812,166 |
Wild-type p53 in cancer cells: when a guardian turns into a blackguard. | The tumor suppressor p53 controls a broad range of cellular responses. Induction of a transient (cell cycle arrest) or a permanent (senescence) block of cell proliferation, or the activation of cell death pathways in response to genotoxic stress comprise the major arms of the survival-death axis governed by p53. Due to these biological properties, inactivation of p53 is a crucial step in tumor development and progression, reflected by the high incidence of TP53 mutations in different types of human cancers. The remarkable potency of p53 in suppressing tumorigenic outgrowth has promoted the expectation that tumor cells expressing wild-type p53 (wtp53) should be more prone to elimination by cytotoxic treatments than tumor cells expressing mutant p53 (mutp53) with defunct wtp53 activities. However, recent findings yielded somewhat unexpected insights concerning the preponderance of the survival-promoting effects of wtp53 in cancer cells, a rather undesired property from the therapeutic point of view. In this commentary we will discuss the possibility that the developmentally established distinct patterns of wtp53 mediated responses in different tissues are an important factor in determining the ultimate outcome of cellular responses mediated by wtp53 in different types of tumor cells, with a particular focus on the divergent impact of wtp53 in malignant tumors of the central nervous system. We infer that a selective gain of pro-survival functions of wtp53 in cancer cells will confer a survival advantage that counteracts tumor therapy. | 18,812,169 |
Role of loops in the guanine quadruplex formation by DNA/RNA hybrid analogs of G4T4G4. | CD spectroscopy, gel electrophoresis and absorption-based thermal stability were used to analyze quadruplex formation of RNA and RNA/DNA hybrid analogs of the deoxyoligonucleotide G4T4G4, which forms a well-characterized basket-type quadruplex. All RNA-containing dodecamers, g4u4g4, G4u4G4 and g4T4g4 (RNA lower-case, DNA capital letters), formed parallel, namely tetramolecular quadruplexes in Na+-containing solutions. The u4 loop forced DNA tetrads into the same conformation as adopted by g4u4g4. In contrast, the T4 loop destabilized the RNA tetrads. Potassium ions markedly stabilized parallel quadruplexes of RNA-containing analogs as well as their bimolecular folding. In the presence of K+, g4T4g4 formed exclusively bimolecular quadruplexes of both parallel and antiparallel types as indicated by CD. Thus, the T4 loop permits RNA strands to adopt an antiparallel arrangement. These findings may be useful for engineering particular quadruplex foldings in different quadruplex-forming sequences. | 18,812,187 |
Rheological investigation on hyaluronan-fibrinogen interaction. | This paper concerns the interaction between hyaluronan and fibrinogen as model for protein-polysaccharide interaction. From rheological investigation, it is shown that a 3D physical network is promoted by mixing the two components; the mechanism is attributed to electrostatic interactions. The influences of the molecular weight and of the hyaluronan concentration are examined; the loose interaction obtained for addition of small amount of soluble protein induces a non-Newtonian behaviour which may be in direct relation with the behaviour observed previously on synovial fluids. | 18,812,188 |
The toxicology of Clioquinol. | 5-Chloro-7-iodo-quinolin-8-ol (Clioquinol) is a halogenated 8-hydroxyquinoline that was used in 1950-1970s as an oral anti-parasitic agent for the treatment and prevention of intestinal amebiasis. However in the 1970s oral Clioquinol was withdrawn from the market due to reports of neurotoxicity in Japanese patients. Recently, reports have demonstrated that Clioquinol has activities beyond its use as an antimicrobial. For example, Clioquinol inhibits the function of the proteasome and displays preclinical efficacy in the treatment of malignancy. In addition, due to its ability to bind copper and dissolve beta-amyloid plaques in the brain, Clioquinol has been investigated for the treatment of Alzheimer's disease. As such, efforts are underway to repurpose Clioquinol. In light of the reemergence of oral Clioquinol, we review the toxicology of this compound in animals and humans with an emphasis on its neurotoxicity. Such information will aid in the design of clinical trials of oral Clioquinol for new indications such as cancer therapy. | 18,812,216 |
Harmonic scalpel versus conventional electrosurgery in the treatment of vulvar cancer. | To compare differences in blood loss, operative time, and intra- and postoperative complications with the harmonic scalpel or conventional electrosurgery in the treatment of vulvar cancer. Consecutive patients who underwent radical vulvectomy with inguinal lymphadenectomy using the harmonic scalpel (HS) or conventional electrosurgery (CE) were compared. A total of 42 patients were included, 22 in the HS group and 20 in the CE group. Mean blood loss was significantly less in the HS group compared with the CE group (127 mL vs 210 mL; P<0.05) and mean operative time was significantly shorter with the HS compared with CE (117 minutes vs 142 minutes; P<0.05). There were no significant differences between the 2 groups in postoperative complications. Use of the harmonic scalpel for surgical treatment of vulvar cancer is safe and has several advantages, including decreased operative time and blood loss, improved visibility in the operative field, and good postoperative outcome. | 18,812,244 |
Ultrasonic dyeing of cationized cotton fabric with natural dye. Part 1: cationization of cotton using Solfix E. | The dyeing of cationized cotton fabric with Solfix E using colouring matter extracted from Cochineal dye has been studied using both conventional and ultrasonic techniques. Factors affecting dye extraction such as ultrasound power, particle size, extraction temperature and time were studied. The results indicated that the extraction by ultrasound at 300 W was more effective at lower temperature and time than conventional extraction. The effect of various factors of dye bath such as pH, salt concentration, ultrasound power, dyeing time and temperature were investigated. The colour strength values obtained were found to be higher with ultrasound than with conventional techniques. The results of fastness properties of the dyed fabrics were fair to good. The scanning electron microscope (SEM) images of the morphological and X-ray analyzes were measured for cationized cotton fabrics dyed with both conventional and ultrasound methods, thus showing the sonicator efficiency. | 18,812,264 |
Analysis of depth of anesthesia with Hilbert-Huang spectral entropy. | Monitoring the effect of anesthetic drug on the neural system is an ongoing challenge for anesthetists. Several methods based on the electroencephalogram (EEG) have been proposed to estimate the depth of anesthesia (DoA); for instance, the Fourier-based time-frequency balanced spectral entropy as implemented in the Datex-Ohmeda M-Entropy Module. In this paper, a novel method based on Hilbert-Huang transform is proposed to calculate a spectral entropy value, called Hilbert-Huang spectral entropy and is applied to EEG recordings during sevoflurane anesthesia. The dose-response relation of Hilbert-Huang spectral entropy during sevoflurane anesthesia is presented. We analyzed a previously collected set of EEG data, obtained from 14 patients' during the induction of general anesthesia with sevoflurane. The Hilbert-Huang spectral entropy and the Datex-Ohmeda M-Entropy were applied to the EEG recording. State entropy and response entropy based on the Hilbert-Huang spectral entropy and the Datex-Ohmeda M-Entropy were calculated, respectively. The performance of both methods was assessed by pharmacokinetic/pharmacodynamic modeling and prediction probability. To obtain reliable Hilbert-Huang spectral entropy and Datex-Ohmeda M-Entropy values, a combined preprocessor was applied in advance. In the awake state, the baseline variability (as estimated by the coefficient of variation) of the Hilbert-Huang spectral entropy was less than half the variability of the Datex-Ohmeda M-Entropy (p<0.001). All entropy values decreased similarly with increasing sevoflurane concentration, as shown by the high correlation between the respective methods (p<0.001). However, Hilbert-Huang spectral entropy exhibited greater resistance to noise in the EEG signal; and decreased in a more linear fashion with increasing sevoflurane effect-site concentration, particularly around the point of loss of consciousness. The goodness-of-fit of the pharmacokinetic/pharmacodynamic model and the prediction probability using the state entropy of Hilbert-Huang spectrum (R2=0.86, P(k)=0.84) was significantly better than that using the one of M-Entropy (R2=0.80, P(k)=0.81, p<0.05); however, the difference between response entropy values was not statistically significant. The results from this small dataset suggest that the Hilbert-Huang spectral entropy has a slightly stronger ability to track changes in sevoflurane effect-site concentration than M-Entropy with a stronger noise-resistance. Hilbert-Huang spectral entropy could be incorporated in the design of a new method to estimate the effect of anesthetic drugs on the EEG. | 18,812,265 |
Transferring disease management and health promotion programs to other countries: critical success factors. | Governments and health service providers around the world are under pressure to improve health outcomes while containing rising healthcare costs. In response to such challenges, many regions have implemented services that have been successful in other countries-but 'importing' initiatives has many challenges. This article summarizes factors found to be critical to the success of adapting a US disease management and health promotion programme for use in Italy and the UK. Using three illustrative case studies, it describes how in each region the programme needed to adapt (i) the form and content of the disease management service, (ii) the involvement and integration with local clinicians and services and (iii) the evaluation of programme outcomes. We argue that it is important to implement evidence-based practice by learning lessons from other countries and service initiatives, but that it is equally important to take into consideration the '3Ps' that are critical for successful service implementation: payers, practitioners and patients. | 18,812,326 |
Infarction-exclusion technique with the on-pump beating heart approach for ventricular septal perforation. | We report a successful surgical management of postinfarction ventricular septal perforation by infarction-exclusion technique with the on-pump beating heart approach and concomitant coronary artery bypass grafting. The identification of the suture line by direct inspection and finger palpation could be more accurate in determining contractile, thus viable myocardium supporting the patch, and concomitant coronary artery bypass grafting with on-pump beating heart could minimize the cardioplegia-induced myocardial damage. | 18,812,330 |
Vacuum-assisted closure for mediastinitis after pediatric cardiac surgery. | Two children, aged 1 and 14 years with methicillin-resistant Staphylococcus aureus mediastinitis after pediatric open-heart surgery, were fitted with a vacuum-assisted closure system. Complete healing was achieved in both cases, and primary wound closure could be carried out without an omental flap after 6 and 16 days. | 18,812,337 |
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