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91.

Background

Peru''s HIV epidemic is concentrated among men who have sex with men (MSM). The contribution of alcohol use disorders (AUDs) to known high-risk behaviors associated with HIV transmission in this context has not been well characterized.

Methods

Between June and October 2011, 5,148 sexually active MSM were recruited using convenience sampling in five cities to participate in a cross-sectional bio-behavioral survey. Five high-risk sexual criteria previously associated with incident HIV infection in this setting were selected a priori as the dependent outcomes. Screening for AUDs used the validated Alcohol Use Disorders Identification Test (AUDIT) and AUDS were stratified by severity. Unadjusted and adjusted odds ratios (AOR) were computed to establish the independent correlates of the five dependent outcomes.

Results

The majority (62.8%) of participants met screening criteria for having an AUD, which were independently correlated with each of the following high-risk sexual risk behaviors in the previous 6 months: 1) >5 sexual partners [AOR = 1.76; (1.54–2.02)]; 2) sex with an HIV-infected partner [AOR = 1.29; (1.03–1.62)]; 3) having a sexually transmitted infection [AOR = 1.38; (1.13–1.68)]; 4) being a sex worker [AOR = 1.61; (1.40–1.87)]; and 5) unprotected sex during last encounter [AOR = 1.22; (1.09–1.38)]. Recent drug use was also correlated with having >5 sexual partners [AOR = 1.42 (1.19–1.71)], sex work [AOR = 1.97 (1.63–2.39)] and unprotected sex during last encounter [AOR = 1.31 (1.11–1.54)]. For each dependent variable, the association with AUDs significantly increased with increasing AUD severity.

Conclusions

AUDs are highly prevalent among MSM in Peru and are associated with increased HIV risk-taking behaviors that are associated with HIV transmission. Strategies that target problematic drinking such as medication-assisted therapy, behavioral counseling and structural interventions could potentially reduce risky behaviors and ultimately reduce HIV transmission among MSM in Peru.  相似文献   
92.
Ezrin, Radixin, and Moesin (ERM) proteins play important roles in many cellular processes including cell division. Recent studies have highlighted the implications of their metastatic potential in cancers. ERM’s role in these processes is largely attributed to their ability to link actin filaments to the plasma membrane. In this paper, we show that the ERM protein Moesin directly binds to microtubules in vitro and stabilizes microtubules at the cell cortex in vivo. We identified two evolutionarily conserved residues in the FERM (4.1 protein and ERM) domains of ERMs that mediated the association with microtubules. This ERM–microtubule interaction was required for regulating spindle organization in metaphase and cell shape transformation after anaphase onset but was dispensable for bridging actin filaments to the metaphase cortex. These findings provide a molecular framework for understanding the complex functional interplay between the microtubule and actin cytoskeletons mediated by ERM proteins in mitosis and have broad implications in both physiological and pathological processes that require ERMs.  相似文献   
93.
We report a familial infection caused by Microsporum canis. The first two patients were a 30-year-old female and her son, a 5-year-old boy, who came in contact with a pet dog at a farm house. The boy then suffered from hair loss for 3 months. There were circular and patchy alopecia with diffuse scaling on his scalp. Meanwhile, his mother also developed patchy erythema and scaling on her face. Several weeks later, the boy’s sister, a 4-year-old girl, was noted to have inconspicuous scaly plaques in the center of her scalp. The development of tinea capitis in the two children and tinea corporis in their mother were diagnosed based on the positive KOH examination. Morphologic characteristics and sequencing of the internal transcribed spacers 1 and 2, amplified from primary culture isolates, confirmed that their infections were caused by the zoophilic M. canis. Repetitive sequence-based molecular typing using the DiversiLab system secreted enzymatic activity analysis, and antifungal susceptibility indicated that these isolates might share the same source. The boy and girl were cured by the treatment with oral itraconazole and topical naftifine–ketoconazole cream after washing the hair with 2 % ketoconazole shampoo, and their mother was successfully treated by terbinafine orally in combination with topical application of naftifine–ketoconazole cream.  相似文献   
94.
Non-lethal sampling methods are of great interest for conservation genetic studies to prevent the death of individuals in populations that are threatened or in decline. With this aim, we tested a non-lethal method of partial antennae removal for DNA sampling in two euglossine bee species: Euglossa cordata and Eulaema nigrita. We validated the survival of the individuals through mark–recapture experiments during 16 months. The quality and quantity of the tissue for DNA analysis was verified through amplification and genotyping of nine and eleven microsatellite loci, respectively. Our results from the mark–recapture experiments showed equal recapture rates of individuals with intact and removed antennae (E. cordata χ2 = 2.492, df = 1, p = 0.114; E. nigrita χ2 = 1.683, df = 1, p = 0.194). Microsatellite loci were successfully genotyped in 97.1 and 97.6 % of the E. cordata and E. nigrita individuals, respectively. Our results validate the feasibility of using antennae tissue for DNA genetic analysis without compromising the survival of individual bees.  相似文献   
95.
We have recently resurrected the name Entamoeba nuttalli Castellani, 1908 for a potentially virulent ameba isolate, P19-061405, obtained from a rhesus macaque in Kathmandu, Nepal. The ameba was morphologically indistinguishable from Entamoeba histolytica/Entamoeba dispar/Entamoeba moshkovskii, but located phylogenetically between E. histolytica and E. dispar. To evaluate the prevalence of E. nuttalli infection in wild rhesus macaques, 112 fecal samples were collected in four locations of the Kathmandu Valley. PCR analysis of DNA extracted from the feces showed positive rates of E. nuttalli, E. dispar, E. histolytica and E. moshkovskii of 51%, 12%, 0% and 0%, respectively. A total of 14 E. nuttalli isolates were obtained from four locations, of which 6 were established as axenic cultures. The sequences of the serine-rich protein gene of E. nuttalli isolates differed among four locations although no differences were found in the composition of sequence motifs. Isoenzyme pattern was analyzed in 8 isolates obtained from three locations. In hexokinase, the mobility of the slower migrating band was located between E. histolytica and E. dispar regardless of the culture conditions. These results demonstrate that E. nuttalli is highly prevalent in wild rhesus macaques in Nepal. Rhesus macaques appear to be one of the natural hosts and heterogeneity of the serine-rich protein gene might be useful for geographical typing of isolates.  相似文献   
96.
BackgroundVulvovaginal candidosis is a common infection in young women, and it is associated with high morbidity and high health costs.AimsVulvovaginal candidosis caused by Candida glabrata is a therapeutic challenge due to the acquired resistance of many strains of this species to azole antifungals.MethodsWe present two cases of vaginal candidosis complicated by fluconazole-resistant Candida glabrata, and treated with voriconazole.ResultsBoth patients improved after administration of voriconazole, 400 mg/12 h the first day and then 200 mg every 12 h for 14 days. Their symptoms disappeared and cultures became negative.ConclusionsThese results suggest voriconazole can be used as a therapeutic alternative for this type of candidosis which, although not life threatening, is associated with a high morbidity.  相似文献   
97.
Postweaning management strategies that include an element of social enrichment may reduce weaning stress and improve welfare and productive performance. We analyzed the effect of postweaning handling strategies on welfare and production traits in lambs. After weaning, 36 lambs were assigned to 3 experimental groups with 12 lambs each (control [C], fattening with gentle human female contact [H], and fattening with 2 adult ewes [E]). The average daily gain (ADG) was estimated. Blood samples were taken, and infrared thermography was used to estimate stress variables. There were significant differences among treatments (in favor of alternative strategies) regarding production and stress variables (cortisol, glucose, and creatine kinase). The results suggest that the lambs handled gently during the fattening were less reactive and better able to modulate their physiological stress. The E group adapted better to acute stress than the C group but was less efficient in modulating chronic stress. Both treatments showed higher slaughter live weights and better ADGs compared with the control. The use of social enrichment at weaning, especially to establish a positive human–nonhuman animal bond, alleviates lamb weaning stress and improves welfare and performance.  相似文献   
98.
Adult stem cells maintain tissue homeostasis by their ability to both self-renew and differentiate to distinct cell types. Multiple signaling pathways have been shown to play essential roles as extrinsic cues in maintaining adult stem cell identity and activity. Recent studies also show dynamic regulation by epigenetic mechanisms as intrinsic factors in multiple adult stem cell lineages. Emerging evidence demonstrates intimate crosstalk between these two mechanisms. Misregulation of adult stem cell activity could lead to tumorigenesis, and it has been proposed that cancer stem cells may be responsible for tumor growth and metastasis. However, it is unclear whether cancer stem cells share commonalities with normal adult stem cells. In this review, we will focus on recent discoveries of epigenetic regulation in multiple adult stem cell lineages. We will also discuss how epigenetic mechanisms regulate cancer stem cell activity and probe the common and different features between cancer stem cells and normal adult stem cells.  相似文献   
99.
Alam  Elie  Maaliki  Lama  Nasr  Zeina 《Molecular biology reports》2020,47(8):6083-6090
Molecular Biology Reports - Ribosomal protein S3 (RPS3) is a component of the 40S ribosomal subunit. It is known to function in ribosome biogenesis and as an endonuclease. RPS3 has been shown to be...  相似文献   
100.

Study Background

Vitamin D has wide-ranging effects on the immune system, and studies suggest that low serum vitamin D levels are associated with worse clinical outcomes in HIV. Recent studies have identified an interaction between antiretrovirals used to treat HIV and reduced serum vitamin D levels, but these studies have been done in North American and European populations.

Methods

Using a prospective cohort study design nested in a multinational clinical trial, we examined the effect of three combination antiretroviral (cART) regimens on serum vitamin D levels in 270 cART-naïve, HIV-infected adults in nine diverse countries, (Brazil, Haiti, Peru, Thailand, India, Malawi, South Africa, Zimbabwe and the United States). We evaluated the change between baseline serum vitamin D levels and vitamin D levels 24 and 48 weeks after cART initiation.

Results

Serum vitamin D levels decreased significantly from baseline to 24 weeks among those randomized to efavirenz/lamivudine/zidovudine (mean change: −7.94 [95% Confidence Interval (CI) −10.42, −5.54] ng/ml) and efavirenz/emtricitabine/tenofovir-DF (mean change: −6.66 [95% CI −9.40, −3.92] ng/ml) when compared to those randomized to atazanavir/emtricitabine/didanosine-EC (mean change: −2.29 [95% CI –4.83, 0.25] ng/ml). Vitamin D levels did not change significantly between week 24 and 48. Other factors that significantly affected serum vitamin D change included country (p<0.001), season (p<0.001) and baseline vitamin D level (p<0.001).

Conclusion

Efavirenz-containing cART regimens adversely affected vitamin D levels in patients from economically, geographically and racially diverse resource-limited settings. This effect was most pronounced early after cART initiation. Research is needed to define the role of Vitamin D supplementation in HIV care.  相似文献   
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