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1.
Mult Scler Relat Disord ; 37: 101478, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31704546

RESUMO

Disease course in people with multiple sclerosis (MS) is heterogeneous. The impact of dietary and nutritional factors on MS prognosis is of interest to both patients and clinicians; differences in diet are hypothesized to contribute to disease evolution over time. However, studying diet, especially in people with MS, introduces methodologic complexity that should be recognized. In this review, we focus on methodological aspects relevant to the conduct of dietary interventions in people with MS, given our experience in leading such studies and the challenges we encountered in the realization of this work. We summarize key aspects of study design and important considerations, regardless of the specifics of the actual study (e.g. the particular diet of interest, target MS population, etc.). We discuss strategies for the design of the intervention as well as the selection of appropriate study endpoints. Finally, we provide an overview of strategies to improve the rigor of conducting dietary studies in people with MS.

2.
Mol Psychiatry ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591465

RESUMO

Schizophrenia is a common, chronic and debilitating neuropsychiatric syndrome affecting tens of millions of individuals worldwide. While rare genetic variants play a role in the etiology of schizophrenia, most of the currently explained liability is within common variation, suggesting that variation predating the human diaspora out of Africa harbors a large fraction of the common variant attributable heritability. However, common variant association studies in schizophrenia have concentrated mainly on cohorts of European descent. We describe genome-wide association studies of 6152 cases and 3918 controls of admixed African ancestry, and of 1234 cases and 3090 controls of Latino ancestry, representing the largest such study in these populations to date. Combining results from the samples with African ancestry with summary statistics from the Psychiatric Genomics Consortium (PGC) study of schizophrenia yielded seven newly genome-wide significant loci, and we identified an additional eight loci by incorporating the results from samples with Latino ancestry. Leveraging population differences in patterns of linkage disequilibrium, we achieve improved fine-mapping resolution at 22 previously reported and 4 newly significant loci. Polygenic risk score profiling revealed improved prediction based on trans-ancestry meta-analysis results for admixed African (Nagelkerke's R2 = 0.032; liability R2 = 0.017; P < 10-52), Latino (Nagelkerke's R2 = 0.089; liability R2 = 0.021; P < 10-58), and European individuals (Nagelkerke's R2 = 0.089; liability R2 = 0.037; P < 10-113), further highlighting the advantages of incorporating data from diverse human populations.

3.
Arch Sex Behav ; 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664555

RESUMO

Earlier age of first sex has potential direct and indirect health effects later in life. Though there are multiple nationwide general population studies on ages of first sex, there is no such nationwide study of first male-male oral or anal sex among men who have sex with men (MSM). This may be important for understanding racial/ethnic disparities in HIV and sexually transmitted infection acquisition among young racial/ethnic minority MSM. Our study examined the birth cohort and racial/ethnic differences in ages of first male-male oral and anal sex using a diverse 2015 U.S. nationwide sample of 10,217 sexually active MSM. The mean age of first male-male oral sex was 18.0 years. Compared with older birth cohorts, those MSM born 1990-2000 were more likely to have younger age of first male-male oral sex. Compared to white MSM, Hispanic MSM and non-Hispanic black MSM were more likely to have younger age of first male-male oral sex with a man. The mean age of first male-male anal sex was 20.3 years. Compared with older birth cohorts, those MSM born 1990-2000 were more likely to have younger age of first male-male anal sex. Compared to white MSM, MSM of all other racial/ethnic groups were more likely to have younger age of first male-male anal sex. These findings emphasize the need for comprehensive and MSM-inclusive sexual health education for young teens and online sexual health resources for young gay, bisexual, queer, and other MSM.

4.
Biol Psychiatry ; 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31606138

RESUMO

BACKGROUND: Nonrandom mating has been shown for psychiatric diagnoses, with hypothesized-but not quantified-implications for offspring liability. This national cohort study enumerated the incidence of major psychiatric disorders among the offspring of parent pairs affected with schizophrenia (SCZ) and/or bipolar disorder (BIP) (i.e., dual-affected pairs). METHODS: Participants were all Swedish residents alive or born between 1968 and 2013 (n = 4,255,196 unique pairs and 8,343,951 offspring). Offspring with dual-affected, single-affected, and unaffected parents were followed (1973-2013) for incidence of broad psychiatric disorders. Primary outcomes included hazard ratio (HR) and cumulative incidence for SCZ and BIP in the offspring. Additional outcomes included any neuropsychiatric, anxiety, depressive, personality, or substance use disorders. Cumulative incidences of SCZ and BIP were used to inform heritability models for these disorders. RESULTS: Hazards were highest within disorder (e.g., offspring of dual-SCZ pairs had sharply raised hazards for SCZ [HR = 55.3]); however, they were significantly raised for all diagnoses (HR range = 2.89-11.84). Incidences were significantly higher for the majority of outcomes, with 43.4% to 48.5% diagnosed with "any" disorder over follow-up. Risks were retained, with modest attenuations, for the offspring of heterotypic pairs. The estimated heritability of liability for SCZ (h2 = 0.62, 95% confidence interval = 0.55-0.70) and BIP (h2 = 0.52, 95% confidence interval = 0.46-0.58) did not differ significantly from estimates derived from single-affected parents. CONCLUSIONS: Risks for a broad spectrum of psychiatric diagnoses are significantly raised in the offspring of dual-affected parents, in line with expectations from a polygenic model of liability to disease risk. How these risks may contribute to population maintenance of these disorders is considered.

5.
Cell ; 179(3): 589-603, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31607513

RESUMO

Genome-wide association studies (GWASs) have focused primarily on populations of European descent, but it is essential that diverse populations become better represented. Increasing diversity among study participants will advance our understanding of genetic architecture in all populations and ensure that genetic research is broadly applicable. To facilitate and promote research in multi-ancestry and admixed cohorts, we outline key methodological considerations and highlight opportunities, challenges, solutions, and areas in need of development. Despite the perception that analyzing genetic data from diverse populations is difficult, it is scientifically and ethically imperative, and there is an expanding analytical toolbox to do it well.

6.
J Int AIDS Soc ; 22(10): e25399, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31592575

RESUMO

INTRODUCTION: Delays between receiving a PrEP prescription and taking a first dose increase the risk of HIV infection. This is especially relevant in populations with high HIV incidence, such as young black men who have sex with men (YBMSM) in the United States. Additionally, YBMSM have relatively low levels of health insurance. We investigated whether lack of health insurance and reliance on PrEP funding through the manufacturer assistance programme (MAP) leads to delays in initiation of PrEP. METHODS: HIV-negative YBMSM were offered PrEP as part of a prospective cohort. Enrolment began in June 2015 with follow-up through February 2019. Interested participants attended a PrEP clinician visit and received a prescription. Those with health insurance received a copay assistance card; those without insurance accessed PrEP using the MAP. The primary outcome was the days between prescription and initiation. The effect of insurance status on this delay was modelled using a Cox proportional hazards model. RESULTS AND DISCUSSION: The median delay between receipt of a PrEP prescription and taking a first dose was 12 days (IQR 3 to 32). Compared to uninsured participants, the adjusted hazard ratio for PrEP initiation for those with insurance was 2.72 (95% CI 1.82 to 4.06). The adjusted median time to initiation for insured participants was 5 days versus 21 days for those without insurance (p < 0.0001). Older age and STI diagnosis were also associated with faster PrEP initiation. Despite equivalent access to PrEP provided by the study, YBMSM without insurance had longer delays in initiation after receipt of a prescription. Overall, the observed delay in PrEP initiation increases the chances of HIV infection and the possibility of PrEP initiation after undetected seroconversion. CONCLUSIONS: The extended time period between PrEP prescription and taking a first dose increases the risk of HIV transmission. Younger YBMSM and those without health insurance had longer delays in PrEP initiation. Immediate PrEP initiation programmes could decrease the likelihood of this occurrence and mitigate the disparity in initiation between those with and without health insurance. Clinical Trial Number: NCT02503618.

8.
J Exp Med ; 216(11): 2546-2561, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31601677

RESUMO

Chronic activation of brain innate immunity is a prominent feature of Alzheimer's disease (AD) and primary tauopathies. However, to what degree innate immunity contributes to neurodegeneration as compared with pathological protein-induced neurotoxicity, and the requirement of a particular glial cell type in neurodegeneration, are still unclear. Here we demonstrate that microglia-mediated damage, rather than pathological tau-induced direct neurotoxicity, is the leading force driving neurodegeneration in a tauopathy mouse model. Importantly, the progression of ptau pathology is also driven by microglia. In addition, we found that APOE, the strongest genetic risk factor for AD, regulates neurodegeneration predominantly by modulating microglial activation, although a minor role of apoE in regulating ptau and insoluble tau formation independent of its immunomodulatory function was also identified. Our results suggest that therapeutic strategies targeting microglia may represent an effective approach to prevent disease progression in the setting of tauopathy.

9.
Sex Health ; 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31610140

RESUMO

Condoms are highly effective for HIV prevention, yet are not currently indicated by the US Food and Drug Administration (FDA) for anal sex. We surveyed a national sample of men who have sex with men to assess whether FDA label indication could affect anticipated condom use, and to determine levels of perceived condom failure for anal sex. We found that 69% of respondents anticipated that a label indication change would increase their likelihood of condom use. Median perceived failure was 15%. We anticipate that these results may aid the FDA in developing standards for a label indication for anal sex.

10.
Biol Psychiatry ; 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31570195

RESUMO

BACKGROUND: The prevalence of depression is higher in individuals with autoimmune diseases, but the mechanisms underlying the observed comorbidities are unknown. Shared genetic etiology is a plausible explanation for the overlap, and in this study we tested whether genetic variation in the major histocompatibility complex (MHC), which is associated with risk for autoimmune diseases, is also associated with risk for depression. METHODS: We fine-mapped the classical MHC (chr6: 29.6-33.1 Mb), imputing 216 human leukocyte antigen (HLA) alleles and 4 complement component 4 (C4) haplotypes in studies from the Psychiatric Genomics Consortium Major Depressive Disorder Working Group and the UK Biobank. The total sample size was 45,149 depression cases and 86,698 controls. We tested for association between depression status and imputed MHC variants, applying both a region-wide significance threshold (3.9 × 10-6) and a candidate threshold (1.6 × 10-4). RESULTS: No HLA alleles or C4 haplotypes were associated with depression at the region-wide threshold. HLA-B*08:01 was associated with modest protection for depression at the candidate threshold for testing in HLA genes in the meta-analysis (odds ratio = 0.98, 95% confidence interval = 0.97-0.99). CONCLUSIONS: We found no evidence that an increased risk for depression was conferred by HLA alleles, which play a major role in the genetic susceptibility to autoimmune diseases, or C4 haplotypes, which are strongly associated with schizophrenia. These results suggest that any HLA or C4 variants associated with depression either are rare or have very modest effect sizes.

11.
J Acquir Immune Defic Syndr ; 82 Suppl 2: S133-S141, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31658201

RESUMO

BACKGROUND: The United States Centers for Disease Control and Prevention promote HIV testing every 6 months among young men who have sex with men (YMSM) to facilitate entry into the HIV prevention and care continuum. Willingness to be tested may be influenced by testing services' quality. Using a novel mystery shopper methodology, we assessed YMSM's testing experiences in 3 cities and recommend service delivery improvements. METHODS: We assessed YMSM's experiences at HIV testing sites in Philadelphia (n = 30), Atlanta (n = 17), and Houston (n = 19). YMSM (18-24) were trained as mystery shoppers and each site was visited twice. After each visit, shoppers completed a quality assurance survey to evaluate their experience. Data were pooled across sites, normed as percentages, and compared across cities. RESULTS: Across cites, visits averaged 30 minutes (SD = 25.5) and were perceived as welcoming and friendly (70.9%). YMSM perceived most sites respected their privacy and confidentiality (84.3%). YMSM noted deficiencies in providers' competencies with sexual minorities (63.4%) and comfort during the visit (65.7%). Sites underperformed on Lesbian, Gay, Bisexual, Transgender visibility (49.6%) and medical forms inclusivity (57.95%). Sites on average did not discuss YMSM's relationship context (49.8%) nor provide risk reduction counseling (56.8%) or safer sex education (24.3%). Sites delivered pre-exposure prophylaxis information and counseling inconsistently (58.8%). CONCLUSIONS: Testing sites' variable performance underscores the importance of improving HIV testing services for YMSM. Strategies are recommended for testing sites to promote cultural sensitivity: funding staff trainings, creating systems to assess adherence to testing guidelines and best practices, and implementing new service delivery models.

13.
Arch Sex Behav ; 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31552572

RESUMO

Existing social stress frameworks largely conceive of stress as emanating from individual experience. Recent theory and research concerning minority stress have focused on same-sex couples' experiences of both eventful and chronic stressors associated with being in a stigmatized relationship, including having ongoing or episodic fears of discrimination, and experiencing actual acts of discrimination. Such couple-level minority stressors represent a novel domain of social stress affecting minority populations that is only beginning to become a focus in empirical investigations testing minority stress theory. This article presents the results of psychometric analyses of dyadic data from 106 same-sex couples from across the U.S., introducing the Couple-Level Minority Stress (CLMS) scale featuring eight new couple-level minority stress factors: (1) Couple-Level Stigma; (2) Couple-Level Discrimination; (3) Seeking Safety as a Couple; (4) Perceived Unequal Relationship Recognition; (5) Couple-Level Visibility; (6) Managing Stereotypes about Same-Sex Couples; (7) Lack of Integration with Families of Origin; and (8) Lack of Social Support for Couples. The CLMS demonstrated a clear factor structure with satisfactory model-data fit and subscale reliabilities. The CLMS also exhibited validity as a correlate of one indicator of relationship quality (relationship satisfaction) and three indicators of mental health (nonspecific psychological distress, depressive symptomatology, and problematic drinking) when controlling for individual-level minority stressors and has great potential to extend and enrich minority stress research, particularly studies that deepen understandings of longstanding health inequities based on sexual orientation.

14.
Nat Commun ; 10(1): 4400, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31562333

RESUMO

A surveillance system in mammals constantly monitors cell activity to protect against aberrant proliferation in response to damage, injury and oncogenic stress. Here we isolate and culture connective tissue fibroblasts from highly regenerative mammals (Acomys and Oryctolagus) to determine how these cells interpret signals that normally induce cellular senescence in non-regenerating mammals (Mus and Rattus). While H2O2 exposure substantially decreases cell proliferation and increases p53, p21, p16, and p19 in cells from mice and rats, cells from spiny mice and rabbits are highly resistant to H2O2. Quantifying oxygen consumption and mitochondrial stability, we demonstrate that increased intracellular H2O2 is rapidly detoxified in regenerating species, but overwhelms antioxidant scavenging in cells from non-regenerative mammals. However, pretreatment with N-acetylcysteine (NAC) protects mouse and rat cells from ROS-induced cellular senescence. Collectively, our results show that intrinsic cellular differences in stress-sensing mechanisms partially explain interspecific variation in regenerative ability.

15.
Curr Med Res Opin ; : 1-10, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31491337

RESUMO

Objective: Uncontrolled asthma is associated with considerable clinical burden and costs to payers and patients. US economic models evaluating biologics using data from clinical trials demonstrate high incremental cost-effectiveness ratios (ICERs), but the cost-effectiveness based on real-world treatment patterns is unknown. This analysis used real-world evidence to assess the cost-effectiveness of adding omalizumab to standard of care (SOC). Methods: A Markov model was applied to track patients' health states in 2-week cycles, comparing costs and treatment effects of SOC alone versus SOC + omalizumab over a lifetime (US payer perspective). Outcomes included exacerbation events, life years, quality-adjusted life years (QALYs), total costs, and an ICER. Patient characteristics, exacerbations, patient-reported outcomes, and work productivity were derived from the real-world PROSPERO (Prospective Study to Evaluate Predictors of Clinical Effectiveness in Response to Omalizumab) study. Published literature informed mortality, exacerbation-related disutility, and unit costs. Sensitivity analyses assessed model robustness. Results: Over a lifetime horizon, omalizumab was associated with an increase of 2.0 QALYs at a cost of $US 148,319 in patients with uncontrolled asthma (ICER of $75,319/QALY gained) and a reduction in exacerbations of 6.0 events/patient. Accounting for responder status improved the ICER ($70,505/QALY); incorporating indirect costs further reduced the ICER. One-way and multivariate sensitivity analyses confirmed that the base case outcome was robust to variation in inputs. Conclusions: Based on real-world outcomes, omalizumab may be cost-effective for uncontrolled asthma from the US payer perspective. Including broader evidence on treatment discontinuation, caregiver burden, and oral corticosteroid reduction from real-world studies may better reflect the effects and value of omalizumab for all healthcare stakeholders.

17.
Clin Infect Dis ; 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31499518

RESUMO

BACKGROUND: HIV pre-exposure prophylaxis (PrEP) has great potential to reduce HIV incidence among young black men who have sex with men (YBMSM) but initiation and persistence for this group remain low. We sought to understand the patterns and predictors of PrEP uptake and discontinuation among YBMSM in Atlanta, Georgia. METHODS: PrEP was offered to all participants in a prospective cohort of HIV-negative YBMSM aged 18-29. For initiators, time on and off PrEP was recorded. Time to PrEP uptake, first discontinuation, and final discontinuation were assessed with the Kaplan-Meier method, with Cox proportional hazard models used to identify factors associated with uptake and discontinuation. RESULTS: After 440 person-years of follow-up, 44% of YBMSM initiated PrEP through the study after a median of 122 days (IQR 44-275). Of PrEP initiators, 69% had a first discontinuation and 40% had a final discontinuation during the study period. The median time to first PrEP discontinuation was 159 days (IQR 97-237). Factors associated with PrEP uptake included higher self-efficacy, sexually transmitted infection, and condomless anal intercourse. Factors associated with discontinuation included younger age, cannabis use, STI, and fewer sex partners. HIV incidence was 5.23/100 person-years (95% CI 3.40-7.23) with lower rate among those who started PrEP (incidence rate ratio 0.39 [95% CI 0.16-0.92]). CONCLUSIONS: Persistent PrEP coverage in this cohort of YBMSM was suboptimal and discontinuations common despite additional support services available through the study. Interventions to support PrEP uptake and persistence, especially for younger and substance-using YBMSM, will be necessary to achieve full PrEP effectiveness.

18.
Sci Data ; 6(1): 180, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31551426

RESUMO

Schizophrenia and bipolar disorder are serious mental illnesses that affect more than 2% of adults. While large-scale genetics studies have identified genomic regions associated with disease risk, less is known about the molecular mechanisms by which risk alleles with small effects lead to schizophrenia and bipolar disorder. In order to fill this gap between genetics and disease phenotype, we have undertaken a multi-cohort genomics study of postmortem brains from controls, individuals with schizophrenia and bipolar disorder. Here we present a public resource of functional genomic data from the dorsolateral prefrontal cortex (DLPFC; Brodmann areas 9 and 46) of 986 individuals from 4 separate brain banks, including 353 diagnosed with schizophrenia and 120 with bipolar disorder. The genomic data include RNA-seq and SNP genotypes on 980 individuals, and ATAC-seq on 269 individuals, of which 264 are a subset of individuals with RNA-seq. We have performed extensive preprocessing and quality control on these data so that the research community can take advantage of this public resource available on the Synapse platform at http://CommonMind.org .

19.
Ecology ; : e02878, 2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31471977

RESUMO

Trees growing near the Arctic treeline have long been used to reconstruct past climates. However, recent studies have shown deterioration of historically strong positive correlations between air temperature and tree growth (known as "divergence"). Divergence has important implications for confidence in paleoclimate reconstructions and ecosystem-atmosphere carbon exchange. Studies in the Brooks Range of northern Alaska showed that white spruce in the west increased growth in response to late 20th century warming, whereas those in the east failed to show a growth increase. In an earlier study across four watersheds in the Brooks Range, we tested and rejected the hypothesis that divergence in the easternmost watershed reflects moisture limitation of growth. Here, using 16 sites distributed across the same four watersheds, we tested an alternative hypothesis, that greater nutrient limitation in the east may have impeded positive growth responses to warming. Climate comparison across the four Brooks Range study watersheds revealed that, although the easternmost watershed generally had a drier growing-season climate, the most consistent difference was that winter air temperature and both winter and summer soil temperatures were much colder in the central and eastern watersheds. Soil nutrient availability, foliar nutrient concentrations, and tree growth were all generally lower in the central and eastern than in the western watersheds. Foliar phosphorus concentration was the best predictor of spatial variation in branch extension growth-a finding that is somewhat inconsistent with the theory that forest productivity on young, glacially derived soils should be strongly nitrogen limited. Experimental fertilization yielded the greatest growth increase in the eastern, an intermediate response in the central, and the smallest growth increase in the western watershed, generally mirroring trends in soil temperature, soil nutrient availability, foliar nutrient concentrations, and growth of control trees. Our results confirm that growth in the easternmost watershed is more nutrient limited and suggest that phosphorus limitation may be at least as important as nitrogen limitation of growth. We hypothesize that cold soil effects on tree access to nutrients might explain divergence in the eastern Brooks Range and elsewhere near the Arctic treeline, particularly in areas with cold winters and widespread permafrost.

20.
Eur J Pharm Biopharm ; 144: 252-265, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31563633

RESUMO

Nanoscale cerium dioxide (nanoceria) has industrial applications, capitalizing on its catalytic, abrasive, and energy storage properties. It auto-catalytically cycles between Ce3+ and Ce4+, giving it pro-and anti-oxidative properties. The latter mediates beneficial effects in models of diseases that have oxidative stress/inflammation components. Engineered nanoparticles become coated after body fluid exposure, creating a corona, which can greatly influence their fate and effects. Very little has been reported about nanoceria surface changes and biological effects after pulmonary or gastrointestinal fluid exposure. The study objective was to address the hypothesis that simulated biological fluid (SBF) exposure changes nanoceria's surface properties and biological activity. This was investigated by measuring the physicochemical properties of nanoceria with a citric acid coating (size; morphology; crystal structure; surface elemental composition, charge, and functional groups; and weight) before and after exposure to simulated lung, gastric, and intestinal fluids. SBF-exposed nanoceria biological effect was assessed as A549 or Caco-2 cell resazurin metabolism and mitochondrial oxygen consumption rate. SBF exposure resulted in loss or overcoating of nanoceria's surface citrate, greater nanoceria agglomeration, deposition of some SBF components on nanoceria's surface, and small changes in its zeta potential. The engineered nanoceria and SBF-exposed nanoceria produced no statistically significant changes in cell viability or cellular oxygen consumption rates.

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