ObjectiveSexual minority men (SMM) living with HIV report significantly greater methamphetamine use compared with heterosexual and HIV-negative peers. Greater use may be related to stressors (e.g., ...HIV-related stigma) faced by SMM living with HIV and subsequent psychological and behavioral sequelae. We tested an integrated theoretical model comprised of pathways between stigma, discrimination, childhood sexual abuse, psychological distress, sexual compulsivity, and cognitive escape in predicting methamphetamine use among SMM living with HIV.MethodsAmong 423 SMM living with HIV, we tested a structural equation model examining factors hypothesized to be directly and indirectly associated with methamphetamine use. Analyses were adjusted for demographic covariates and sampling bias.ResultsThe model showed good fit (CFI = 0.96, RMSEA = 0.01). Heterosexist discrimination was associated with psychological distress (β = 0.39, p < 0.001) and psychological distress was associated with sexual compulsivity (β = 0.33, p < 0.001). Sexual compulsivity was associated with cognitive escape (β = 0.31, p < 0.001), which was associated with methamphetamine use (β = 0.51, p < 0.001). Psychological distress was associated with methamphetamine use via serial indirect effects of sexual compulsivity and cognitive escape (β = 0.05, p < 0.05).ConclusionsHeterosexist discrimination contributed to psychological distress among SMM living with HIV. Psychological distress is linked to methamphetamine use via sexual compulsivity and cognitive avoidance. Interventions seeking to reduce the likelihood that SMM living with HIV use methamphetamine should include coping strategies specific to heterosexism and related psychological distress.
Organic photochromic molecules including diarylethenes are of particular interest for their numerous potential applications including high-density optical data storage and light-activated switches. ...In this report, we examined the temperature dependence of the light-drive photocyclization reaction in a classic diarylethene. The steady-state populations were monitored spectroscopically and by temperature dependent in situ photocrystallography, the latter being the first reported example of this technique. The observed decrease in the steady-state population with decreasing temperature suggests this classic diarylethene possesses an excited-state potential energy surface topology similar to previously reported “inverted” diarylethenes.
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IJS, KILJ, NUK, PNG, UL, UM
A phenanthrene-based diarylethene linker with linear pyridyl connectivity, 4,4'-(9,10-bis(2,5-dimethylthiophen-3-yl)phenanthrene-2,7-di yl)dipyridine linker (TPDPy) was prepared and subsequently used ...to synthesize an air-stable metal-organic framework, UBMOF-3 (Zn3(BDC)3(TPDPy)1(DMF)1.5, BDC = 1,4-benzenedicarboxylate, DMF = N,N-dimethylformamide). Upon irradiation with ultraviolet light, this photo-responsive framework, composed of terephthalate, TPDPy, and zinc pinwheels, exhibits strong linear dichroism consistent with the crystal structure. Activation (desolvation) of the crystal leads to a significant change in the crystal structure that improves the ability to crystallographically resolve the photochromic linker.
Objectives
Syphilis rates have increased in BC and disproportionately affect gay, bisexual, and other men who have sex with men (gbMSM). A social marketing campaign (Syphistory) ran from January to ...September 2017 with the primary goal of increasing syphilis knowledge and a secondary goal of increasing syphilis screening among gbMSM in BC.
Methods
We used pre- and post-campaign surveys to assess changes in syphilis knowledge from a convenience sample of clients attending STI clinics using one-sided
t
-tests. We used online Piwik metrics to examine the campaign reach, and provincial testing data to examine trends in syphilis screening. We used data from the Engage Study to examine factors associated with campaign awareness and associations with syphilis testing.
Results
Of the 2155 visitors to the Syphistory website with known geography, 79.4% were from BC. Moreover, STI clinic participants who saw the campaign demonstrated a greater knowledge of syphilis (9.7/12, 80.8%) than those who did not see the campaign (mean 8.9/12, 74%) (
p
< 0.001). Provincial syphilis testing rates were 8764 and 9749 in the 12 months before and after the campaign; however, we did not find an overall trend in testing before versus after the campaign (
p
= 0.147). Among Engage participants, 12.7% reported seeing the campaign and we found an association between campaign exposure and recent syphilis testing (aOR = 2.73; 95% CI = 1.51, 4.93).
Conclusion
gbMSM who saw the campaign were more likely to report being tested for syphilis in the previous 6 months. STI clinic attendees who reported seeing the campaign also had higher syphilis knowledge compared to those who did not.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, ODKLJ, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We explored attitudes of gay, bisexual, and other men who have sex with men (GBM) toward their amphetamine-use and associations with reduced use over time.
We recruited sexually-active GBM aged 16+ ...years in Montreal, Toronto, and Vancouver, Canada, from 02-2017 to 08-2019, with follow-up visits every 6-12 months until November 2020. Among participants who reported past-six-month (P6M) amphetamine-use at enrollment, we used logistic regression to identify demographic, psychological, social, mental health, other substance-use, and behavioral factors associated with reporting needing help reducing their substance-use. We used mixed-effects logistic regression to model reduced P6M amphetamine-use with perceived problematic-use as our primary explanatory variable.
We enrolled 2,449 GBM across sites. 15.5-24.7% reported P6M amphetamine-use at enrollment and 82.6 - 85.7% reported needing no help or only a little help in reducing their substance use. Reporting needing a lot/of help or completely needing help in reducing substance-use was associated with group sex participation (AOR = 2.35, 95%CI:1.25-4.44), greater anxiety symptomatology (AOR = 2.11, 95%CI:1.16-3.83), greater financial strain (AOR = 1.35, 95%CI:1.21-1.50), and greater Escape Motive scores (AOR = 1.07, 95%CI:1.03-1.10). Reductions in P6M amphetamine-use were less likely among GBM who perceived their amphetamine-use as problematic (AOR = 0.17 95% CI 0.10 - 0.29).
Most amphetamine-using GBM did not feel they needed help reducing their substance use, and many reported reduced amphetamine-use at subsequent visits. Those who perceived their use as problematic were less likely to reduce their use. Further interventions to assist GBM in reducing their use are needed to assist those who perceive their use as problematic.
The relative stability and accessibility of atropisomers plays a prominent role in the efficacy of diarylethene-based photochromic materials. Herein, DFT methods, using the ωB97XD functional and a ...6-31G(d) basis, are employed to determine the local energetic minima and maxima which describe the rotation of a thiophene group in derivatives of 9,10-bis(2-methyl-5-pheylthiophen-3-yl)phenanthrene-2,7-dicarboxylic acid, a photochromic linker molecule which exhibits atropisomer-formation-related fatigue when incorporated into a metal–organic framework. Results of these potential energy surface mapping calculations as well as their applications to atropisomer separability are discussed.
Phosphatidylethanolamine methyltransferase (PEMT) generates phosphatidylcholine (PC), the most abundant phospholipid in the mitochondria and an important acyl chain donor for cardiolipin (CL) ...biosynthesis. Mice lacking PEMT (PEMTKO) are cold-intolerant when fed a high-fat diet (HFD) due to unclear mechanisms. The purpose of this study was to determine whether PEMT-derived phospholipids are important for the function of uncoupling protein 1 (UCP1) and thus for maintenance of core temperature.
To test whether PEMT-derived phospholipids are important for UCP1 function, we examined cold-tolerance and brown adipose (BAT) mitochondria from PEMTKO mice with or without HFD feeding. We complemented these studies with experiments on mice lacking functional CL due to tafazzin knockdown (TAZKD). We generated several conditional mouse models to study the tissue-specific roles of PEMT, including mice with BAT-specific knockout of PEMT (PEMT-BKO).
Chow- and HFD-fed PEMTKO mice completely lacked UCP1 protein in BAT, despite a lack of difference in mRNA levels, and the mice were accordingly cold-intolerant. While HFD-fed PEMTKO mice exhibited reduced mitochondrial CL content, this was not observed in chow-fed PEMTKO mice or TAZKD mice, indicating that the lack of UCP1 was not attributable to CL deficiency. Surprisingly, the PEMT-BKO mice exhibited normal UCP1 protein levels. Knockout of PEMT in the adipose tissue (PEMT-AKO), liver (PEMT-LKO), or skeletal muscle (PEMT-MKO) also did not affect UCP1 protein levels, suggesting that lack of PEMT in other non-UCP1-expressing cells communicates to BAT to suppress UCP1. Instead, we identified an untranslated UCP1 splice variant that was triggered during the perinatal period in the PEMTKO mice.
PEMT is required for UCP1 splicing that yields functional protein. This effect is derived by PEMT in nonadipocytes that communicates to BAT during embryonic development. Future research will focus on identifying the non-cell-autonomous PEMT-dependent mechanism of UCP1 splicing.
•Whole-body ablation of PEMT results in a complete loss of UCP1 protein.•While PEMT-derived PC may participate in CL biosynthesis, changes in mitochondrial PC or CL do not explain the loss of UCP1 protein.•PEMT regulates brown adipose UCP1 in a non-cell-autonomous manner.•PEMT deletion promotes the use of an alternative 3’ splice junction in exon 5 of UCP1, preventing UCP1 protein expression.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Exercise capacity is a strong predictor of all-cause mortality. Skeletal muscle mitochondrial respiratory capacity, its biggest contributor, adapts robustly to changes in energy demands induced by ...contractile activity. While transcriptional regulation of mitochondrial enzymes has been extensively studied, there is limited information on how mitochondrial membrane lipids are regulated. Here, we show that exercise training or muscle disuse alters mitochondrial membrane phospholipids including phosphatidylethanolamine (PE). Addition of PE promoted, whereas removal of PE diminished, mitochondrial respiratory capacity. Unexpectedly, skeletal muscle-specific inhibition of mitochondria-autonomous synthesis of PE caused respiratory failure because of metabolic insults in the diaphragm muscle. While mitochondrial PE deficiency coincided with increased oxidative stress, neutralization of the latter did not rescue lethality. These findings highlight the previously underappreciated role of mitochondrial membrane phospholipids in dynamically controlling skeletal muscle energetics and function.
There are many reasons why individuals engage in prosocial behavior; communal sexual altruism is based on the notion that some practice safer sex in the interest of promoting the well‐being of their ...community/in‐group. Given that definitions of what constitutes “safer sex” have changed with advances in human immunodeficiency virus (HIV) prevention, we investigated the importance of communal sexual altruism (herein “altruism”) among urban gay, bisexual, and other sexual minority men (GBM) in the contemporary context. Using a sample of 2449 GBM we examined the association of both safer‐sex‐related attitudes (e.g., HIV treatment optimism–skepticism) and behaviors (e.g., condomless anal sex CAS) with altruism scores. Higher altruism scores were associated with a lower likelihood of CAS and a greater frequency of discussing HIV status with new partners. These findings demonstrate that many GBM are motivated to engage in several kinds of behaviors that improve the well‐being of their in‐group (i.e., the GBM community).
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Introduction
Accessibility of pre‐exposure prophylaxis (PrEP) in Canada remains complex as publicly funded coverage and delivery differs by province. In January 2018, PrEP became publicly funded and ...free of charge in British Columbia (BC), whereas PrEP coverage in Ontario and Montreal is more limited and may require out‐of‐pocket costs. We examined differences over time in PrEP uptake and assessed factors associated with PrEP awareness and use.
Methods
Gay, bisexual and other men who have sex with men (GBM) were recruited through respondent‐driven sampling (RDS) in Toronto, Vancouver and Montreal, Canada, in a prospective biobehavioural cohort study. We applied generalized estimating equations with hierarchical data (RDS chain, participant, visit) to examine temporal trends of PrEP use and correlates of PrEP awareness and use from 2017 to 2020 among self‐reported HIV‐negative/unknown GBM.
Results
Of 2008 self‐identified HIV‐negative/unknown GBM at baseline, 5093 study visits were completed from February 2017 to March 2020. At baseline, overall PrEP awareness was 88% and overall PrEP use was 22.5%. During our study period, we found PrEP use increased in all cities (all p<0.001): Montreal 14.2% during the first time period to 39.3% during the last time period (p<0.001), Toronto 21.4–31.4% (p<0.001) and Vancouver 21.7–59.5% (p<0.001). Across the study period, more Vancouver GBM used PrEP than Montreal GBM (aOR = 2.05, 95% CI = 1.60–2.63), with no significant difference between Toronto and Montreal GBM (aOR = 0.90, 95% CI = 0.68–1.18).
Conclusions
Full free‐of‐charge public funding for PrEP in BC likely contributed to differences in PrEP awareness and use. Increasing public funding for PrEP will improve accessibility and uptake among GBM most at risk of HIV.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
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