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101.

Background

Further research is necessary to understand the factors contributing to the high prevalence of HIV/STIs among men who have sex with men (MSM) in Peru. We compared HIV/STI prevalence and risk factors between two non-probability samples of MSM, one passively enrolled from an STI clinic and the other actively enrolled from community venues surrounding the clinic in Lima, Peru.

Methods

A total of 560 self-identified MSM were enrolled between May-December, 2007. 438 subjects enrolled from a municipal STI clinic and 122 subjects enrolled during community outreach visits. All participants underwent screening for HIV, syphilis, HSV-2, gonorrhoea, and chlamydia and completed a survey assessing their history of HIV/STIs, prior HIV testing, and sexual behavior.

Results

HIV prevalence was significantly higher among MSM enrolled from the clinic, with previously undiagnosed HIV identified in 9.1% compared with 2.6% of community participants. 15.4 % of all MSM screened were infected with ≥1 curable STI, 7.4% with early syphilis (RPR≥1∶16) and 5.5% with urethral gonorrhoea and/or chlamydia. No significant differences between populations were reported in prevalence of STIs, number of male sex partners, history of unprotected anal intercourse, or alcohol and/or drug use prior to sex. Exchange of sex for money or goods was reported by 33.5% of MSM enrolled from the clinic and 21.2% of MSM from the community (p = 0.01).

Conclusions

Our data demonstrate that the prevalence of HIV and STIs, including syphilis, gonorrhoea, and chlamydia are extremely high among MSM enrolled from both clinic and community venues in urban Peru. New strategies are needed to address differences in HIV/STI epidemiology between clinic- and community-enrolled samples of MSM.  相似文献   
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In this study we investigate the composition of the potential honeyeater pollinator community, patterns of honeyeater visitation, pollination and the mating system in a range of population fragments for the bird-pollinated mixed mating system shrub Calothamnus quadrifidus R.Br. Specifically, we aimed to answer the following questions. For smaller and more isolated population fragments are honeyeater species lost from the pollinator community, patterns of visitation different, levels of pollination lower and rates of selfing, biparental inbreeding and correlated paternity higher. The composition of the honeyeater community was similar across population fragments and there was no relationship between the abundance of birds and population fragment size. Honeyeaters were most commonly observed visiting numerous inflorescences within single plants in all populations, but as population fragments became larger movements between plants were more commonly observed. Our observations of honeyeater visitation were generally consistent with our measurements of pollination and patterns in the mating system across population fragments. We found no significant relationship between population fragment size and levels of pollination. Mating system studies showed outcrossing rates (t m) comparable to those found in other bird-pollinated Myrtaceae, and ranged from 0.54 to 0.90 across populations. Outcrossing rates were not significantly correlated with log population size, but correlations of outcrossed paternity indicate a clear trend from low correlated paternity in larger populations to significantly higher correlated paternities in smaller populations. As a consequence mating in small populations will occur between much smaller groups of plants, and this may affect population fitness in subsequent generations.  相似文献   
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Objective To determine the health impact of swimming pools built with the aim of improving quality of life and reducing high rates of pyoderma and otitis media.Design Intervention study assessing prevalence of ear disease and skin infections before and at six monthly intervals after opening of swimming pools.Setting Two remote Aboriginal communities in Western Australia.Participants 84 boys and 78 girls aged < 17 years.Main outcome measures Changes in prevalence and severity of pyoderma and perforation of tympanic membranes with or without otorrhoea over 18 months after opening of pools.Results In community A, 61 children were seen before the pool was opened, and 41, 46, and 33 children were seen at the second, third, and fourth surveys. Equivalent figures for community B were 60, 35, 39, and 45. Prevalence of pyoderma declined significantly from 62% to 18% in community A and from 70% to 20% in community B during the 18 months after the pools opened. Over the same period, prevalence of severe pyoderma fell from 30% to 15% in community A and from 48% to 0% in community B. Prevalence of perforations of the tympanic membrane fell from 32% in both communities to 13% in community A and 18% in community B. School attendance improved in community A.Conclusion Swimming pools in remote communities were associated with reduction in prevalence of pyoderma and tympanic membrane perforations, which could result in long term benefits through reduction in chronic disease burden and improved educational and social outcomes.  相似文献   
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A novel series of CCR5 antagonists has been identified, utilizing the lead, nifeviroc, which were further modified based on bioisosteric principles. Lead optimization was pursued by balancing potential toxicity and potency. Potent analogues with low toxic properties were successfully developed by formation of urea and amide bonds at the nitrogen at position 4- of the pyrrolidine ring.  相似文献   
109.
Invertebrates use a wide range of peptides as transmitters and hormones to regulate complex behaviour, physiology and development. These animals, especially those that are amenable to genetic study and are the subject of genome-sequencing projects, provide powerful model systems for understanding the functions of peptidases in controlling the bioactivity of peptides. Neprilysin, a zinc metallopeptidase and a key enzyme in the metabolism of mammalian peptides, is also implicated in the inactivation of peptides at synapses and of circulating peptide hormones in insects and nematodes. A family of neprilysin-like genes are present in the genomes of both Drosophila melanogaster and Caenorhabditis elegans; in C. elegans it seems that individual family members have evolved to take on different physiological functions, because they are expressed in a tissue-specific manner. Angiotensin I-converting enzymes (peptidyl dipeptidase A, angiotensin-converting enzyme) are another group of zinc metallopeptidases found in some invertebrates that lack angiotensin peptides. In D. melanogaster there are two functional angiotensin-converting enzymes that are essential for normal development. One of these (Acer) is expressed in the embryonic heart, whereas the second enzyme (Ance) is expressed in several tissues at different stages of the life cycle. The accumulation of Ance within secretory vesicles of some peptide-synthesizing cells suggests a role for the enzyme in the intracellular processing of insect peptides. Ance is very efficient at cleaving pairs of basic residues from the C-terminus of partly processed peptides, suggesting a novel role for the enzyme in prohormone processing. Invertebrates will continue to provide insights into the evolutionarily conserved functions of known peptidases and of those additional family members that are expected to be identified in the future from genome-sequencing projects.  相似文献   
110.
Zhang LW  HL Liu  DY Zhang  WG Bian 《Phyton》2015,84(1):58-63
Seed dormancy release and germination of Corispermum lehmannianum Bunge were tested using various treatments: temperature, cold stratification, gibberelins (GA3), dry storage and sand burial. Results showed that temperature and light did not affect the germination of fresh seeds, cold stratification and GA3 could improve seed germination, whereas dry storage and sand burial did not. The germination percentage was highest at 35/20 °C after the cold stratification and GA3 treatments. Corispermum lehmannianum seeds were classified as non-deep, Type-2, physiological dormancy (PD), whose seed dormancy could be released by cold stratification and GA3.  相似文献   
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