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991.
Krishna Jafa Peter McElroy Lisa Fitzpatrick Craig B. Borkowf Robin MacGowan Andrew Margolis Ken Robbins Ae Saekhou Youngpairoj Dale Stratford Alan Greenberg Jennifer Taussig R. Luke Shouse Madeleine LaMarre Eleanor McLellan-Lemal Walid Heneine Patrick S. Sullivan 《PloS one》2009,4(5)
Introduction
HIV prevalence among state prison inmates in the United States is more than five times higher than among nonincarcerated persons, but HIV transmission within U.S. prisons is sparsely documented. We investigated 88 HIV seroconversions reported from 1988–2005 among male Georgia prison inmates.Methods
We analyzed medical and administrative data to describe seroconverters'' HIV testing histories and performed a case-crossover analysis of their risks before and after HIV diagnosis. We sequenced the gag, env, and pol genes of seroconverters'' HIV strains to identify genetically-related HIV transmission clusters and antiretroviral resistance. We combined risk, genetic, and administrative data to describe prison HIV transmission networks.Results
Forty-one (47%) seroconverters were diagnosed with HIV from July 2003–June 2005 when voluntary annual testing was offered. Seroconverters were less likely to report sex (OR [odds ratio] = 0.02, 95% CI [confidence interval]: 0–0.10) and tattooing (OR = 0.03, 95% CI: <0.01–0.20) in prison after their HIV diagnosis than before. Of 67 seroconverters'' specimens tested, 33 (49%) fell into one of 10 genetically-related clusters; of these, 25 (76%) reported sex in prison before their HIV diagnosis. The HIV strains of 8 (61%) of 13 antiretroviral-naïve and 21 (40%) of 52 antiretroviral-treated seroconverters were antiretroviral-resistant.Discussion
Half of all HIV seroconversions were identified when routine voluntary testing was offered, and seroconverters reduced their risks following their diagnosis. Most genetically-related seroconverters reported sex in prison, suggesting HIV transmission through sexual networks. Resistance testing before initiating antiretroviral therapy is important for newly-diagnosed inmates. 相似文献992.
Patty W. Siri‐Tarino Paul T. Williams Harriet S. Fernstrom Robin S. Rawlings Ronald M. Krauss 《Obesity (Silver Spring, Md.)》2009,17(9):1768-1775
Excess adiposity and high‐carbohydrate diets have been associated with an atherogenic lipoprotein phenotype (ALP) characterized by increased concentrations of small, dense low‐density lipoprotein (LDL) particles (pattern B). We tested whether weight loss and normalization of adiposity could reverse ALP in overweight men with pattern B. After consuming a moderate‐carbohydrate, high‐fat diet for 3 weeks, pattern B and nonpattern B (pattern A) men were randomized to a weight loss (n = 60 and n = 36, respectively) or control weight‐stable arm (n = 20 and n = 17, respectively). Men in the weight loss arm consumed ~1,000 fewer calories per day over 9 weeks to induce an average ~9 kg weight loss. In the control group, weight stability was maintained for 4 weeks after randomization. Weight loss led to the conversion of pattern B to pattern A in 58% of baseline pattern B men. Among men who achieved BMIs of <25 kg/m2 (62% of pattern B men vs. 83% of pattern A men), 81% of pattern B men converted to pattern A. Weight loss was associated with a significantly greater decrease in small, dense LDL subclass 3b in pattern B relative to pattern A men. The lipoprotein profiles of pattern A men who converted from pattern B were comparable to those of men with pattern A at baseline. Conversion of LDL subclass pattern B to pattern A and reversal of ALP can be achieved in a high proportion of overweight men by normalization of adiposity. 相似文献
993.
Gordon J. King Kai-En Chen Gautier Robin Jade K. Forwood Bego?a Heras Anil S. Thakur Bostjan Kobe Simon P. Blomberg Jennifer L. Martin 《PloS one》2009,4(11)
Background
Protein crystallisation screening involves the parallel testing of large numbers of candidate conditions with the aim of identifying conditions suitable as a starting point for the production of diffraction quality crystals. Generally, condition screening is performed in 96-well plates. While previous studies have examined the effects of protein construct, protein purity, or crystallisation condition ingredients on protein crystallisation, few have examined the effect of the crystallisation plate.Methodology/Principal Findings
We performed a statistically rigorous examination of protein crystallisation, and evaluated interactions between crystallisation success and plate row/column, different plates of same make, different plate makes and different proteins. From our analysis of protein crystallisation, we found a significant interaction between plate make and the specific protein being crystallised.Conclusions/Significance
Protein crystal structure determination is the principal method for determining protein structure but is limited by the need to produce crystals of the protein under study. Many important proteins are difficult to crystallise, so that identification of factors that assist crystallisation could open up the structure determination of these more challenging targets. Our findings suggest that protein crystallisation success may be improved by matching a protein with its optimal plate make. 相似文献995.
Ten polymorphic loci were isolated and characterized from the milkweed, Asclepias syriaca L., of North America. These loci successfully cross-amplified in A. exaltata L. Polymorphism ranged from two to 16 alleles per locus per species in 68 individuals of A. syriaca and 56 individuals of A. exaltata. Expected heterozygosities ranged from 0.017 to 0.851 and significant deviations from Hardy–Weinberg equilibrium were found
for two and three loci in A. syriaca and A. exaltata, respectively. No linkage disequilibrium was detected. These markers should prove useful for assessing population genetic
structure and interspecific gene flow in these and other species of Asclepias. 相似文献
996.
Alexandre Hainard Natalia Tiberti Xavier Robin Veerle Lejon Dieudonné Mumba Ngoyi Enock Matovu John Charles Enyaru Catherine Fouda Joseph Mathu Ndung'u Frédérique Lisacek Markus Müller Natacha Turck Jean-Charles Sanchez 《PLoS neglected tropical diseases》2009,3(6)
Background
Human African trypanosomiasis (HAT), also known as sleeping sickness, is a parasitic tropical disease. It progresses from the first, haemolymphatic stage to a neurological second stage due to invasion of parasites into the central nervous system (CNS). As treatment depends on the stage of disease, there is a critical need for tools that efficiently discriminate the two stages of HAT. We hypothesized that markers of brain damage discovered by proteomic strategies and inflammation-related proteins could individually or in combination indicate the CNS invasion by the parasite.Methods
Cerebrospinal fluid (CSF) originated from parasitologically confirmed Trypanosoma brucei gambiense patients. Patients were staged on the basis of CSF white blood cell (WBC) count and presence of parasites in CSF. One hundred samples were analysed: 21 from stage 1 (no trypanosomes in CSF and ≤5 WBC/µL) and 79 from stage 2 (trypanosomes in CSF and/or >5 WBC/µL) patients. The concentration of H-FABP, GSTP-1 and S100β in CSF was measured by ELISA. The levels of thirteen inflammation-related proteins (IL-1ra, IL-1β, IL-6, IL-9, IL-10, G-CSF, VEGF, IFN-γ, TNF-α, CCL2, CCL4, CXCL8 and CXCL10) were determined by bead suspension arrays.Results
CXCL10 most accurately distinguished stage 1 and stage 2 patients, with a sensitivity of 84% and specificity of 100%. Rule Induction Like (RIL) analysis defined a panel characterized by CXCL10, CXCL8 and H-FABP that improved the detection of stage 2 patients to 97% sensitivity and 100% specificity.Conclusion
This study highlights the value of CXCL10 as a single biomarker for staging T. b. gambiense-infected HAT patients. Further combination of CXCL10 with H-FABP and CXCL8 results in a panel that efficiently rules in stage 2 HAT patients. As these molecules could potentially be markers of other CNS infections and disorders, these results should be validated in a larger multi-centric cohort including other inflammatory diseases such as cerebral malaria and active tuberculosis. 相似文献997.
Emma M. Harding-Esch Tansy Edwards Ansumana Sillah Isatou Sarr Chrissy H. Roberts Paul Snell Esther Aryee Sandra Molina Martin J. Holland David C. W. Mabey Robin L. Bailey 《PLoS neglected tropical diseases》2009,3(12)
Background
Trachoma has been endemic in The Gambia for decades. National trachoma control activities have been in place since the mid-1980''s, but with no mass antibiotic treatment campaign. We aimed to assess the prevalence of active trachoma and of actual ocular Chlamydia trachomatis infection as measured by polymerase chain reaction (PCR) in the two Gambian regions that had had the highest prevalence of trachoma in the last national survey in 1996 prior to planned national mass antibiotic treatment distribution in 2006.Methodology/Principal Findings
Two stage random sampling survey in 61 randomly selected Enumeration Areas (EAs) in North Bank Region (NBR) and Lower River Region (LRR). Fifty randomly selected children aged under 10 years were examined per EA for clinical signs of trachoma. In LRR, swabs were taken to test for ocular C. trachomatis infection. Unadjusted prevalences of active trachoma were calculated, as would be done in a trachoma control programme. The prevalence of trachomatous inflammation, follicular (TF) in the 2777 children aged 1–9 years was 12.3% (95% CI 8.8%–17.0%) in LRR and 10.0% (95% CI 7.7%–13.0%) in NBR, with significant variation within divisions (p<0.01), and a design effect of 3.474. Infection with C. trachomatis was found in only 0.3% (3/940) of children in LRR.Conclusions/Significance
This study shows a large discrepancy between the prevalence of trachoma clinical signs and ocular C. trachomatis infection in two Gambian regions. Assessment of trachoma based on clinical signs alone may lead to unnecessary treatment, since the prevalence of active trachoma remains high but C. trachomatis infection has all but disappeared. Assuming that repeated infection is required for progression to blinding sequelae, blinding trachoma is on course for elimination by 2020 in The Gambia. 相似文献998.
999.
1000.
Wood ants are a dominant and ecologically important component of northern coniferous forests with interactions at many trophic
levels. Each species exhibits specific habitat preferences which need to be understood if conservation measures are to be
successful. In Britain, the rare narrow-headed ant Formica exsecta has disappeared from much of its former range and is now largely restricted to the highlands of Scotland where it is found
in open canopy woodland and along forest edges. Nest locale of one small and vulnerable population at the edge of its current
range, were compared with those of random locations within the same habitat and with actual nests within the stronghold of
the Abernethy-Glenmore complex in Strathspey. After data exploration with Redundancy Analysis, stepwise multiple regression
was used to create a model which best estimated the variance in nest location using a parsimonious selection of vegetation
and environmental variables. The input variables included were light, soil moisture, altitude, tree stature and distribution,
vegetation structure and composition, and ground characteristics. F. exsecta clearly exhibited preferences for the position of nest mounds in relation to light, vegetation and tree cover. Forest location
was also important in determining which variables nests were affected by. This study highlights the importance of maintaining
a dynamic mosaic of different-aged woodland enabling early successional species such as F. exsecta, with suitable areas to move to as conditions change and allowing the co-existence of all wood ant species. 相似文献