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1.
Nature ; 583(7814): E15, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32541969

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

2.
Biochemistry ; 63(17): 2183-2195, 2024 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-39138154

RESUMO

The Enabled/VASP homology 1 (EVH1) domain is a small module that interacts with proline-rich stretches in its ligands and is found in various signaling and scaffolding proteins. Mena, the mammalian homologue of Ena, is involved in diverse actin-associated events, such as membrane dynamics, bacterial motility, and tumor intravasation and extravasation. Two-dimensional (2D) 1H-15N HSQC NMR was used to study Mena EVH1 binding properties, defining the amino acids involved in ligand recognition for the physiological ligands ActA and PCARE, and a synthetic polyproline-inspired small molecule (hereafter inhibitor 6c). Chemical shift perturbations indicated that proline-rich segments bind in the conserved EVH1 hydrophobic cleft. The PCARE-derived peptide elicited more perturbations compared to the ActA-derived peptide, consistent with a previous report of a structural alteration in the solvent-exposed ß7-ß8 loop. Unexpectedly, EVH1 and the proline-rich segment of PTP1B did not exhibit NMR chemical shift perturbations; however, the high-resolution crystal structure implicated the conserved EVH1 hydrophobic cleft in ligand recognition. Intrinsic steady-state fluorescence and fluorescence polarization assays indicate that residues outside the proline-rich segment enhance the ligand affinity for EVH1 (Kd = 3-8 µM). Inhibitor 6c displayed tighter binding (Kd ∼ 0.3 µM) and occupies the same EVH1 cleft as physiological ligands. These studies revealed that the EVH1 domain enhances ligand affinity through recognition of residues flanking the proline-rich segments. Additionally, a synthetic inhibitor binds more tightly to the EVH1 domain than natural ligands, occupying the same hydrophobic cleft.


Assuntos
Ligação Proteica , Humanos , Ressonância Magnética Nuclear Biomolecular , Domínios Proteicos , Ligantes , Modelos Moleculares , Peptídeos/química , Peptídeos/metabolismo , Prolina/metabolismo , Prolina/química , Sequência de Aminoácidos , Sítios de Ligação , Cristalografia por Raios X , Proteínas dos Microfilamentos/química , Proteínas dos Microfilamentos/metabolismo
3.
PLoS Pathog ; 18(6): e1010573, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35679349

RESUMO

Powassan virus (POWV) is an emerging tick borne flavivirus (TBFV) that causes severe neuroinvasive disease. Currently, there are no approved treatments or vaccines to combat POWV infection. Here, we generated and characterized a nanoparticle immunogen displaying domain III (EDIII) of the POWV E glycoprotein. Immunization with POWV EDIII presented on nanoparticles resulted in significantly higher serum neutralizing titers against POWV than immunization with monomeric POWV EDIII. Furthermore, passive transfer of EDIII-reactive sera protected against POWV challenge in vivo. We isolated and characterized a panel of EDIII-specific monoclonal antibodies (mAbs) and identified several that potently inhibit POWV infection and engage distinct epitopes within the lateral ridge and C-C' loop of the EDIII. By creating a subunit-based nanoparticle immunogen with vaccine potential that elicits antibodies with protective activity against POWV infection, our findings enhance our understanding of the molecular determinants of antibody-mediated neutralization of TBFVs.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Nanopartículas , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , Camundongos
4.
Milbank Q ; 102(2): 429-462, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38282421

RESUMO

Policy Points The 340B Drug Pricing Program accounts for roughly 1 out of every 100 dollars spent in the $4.3 trillion US health care industry. Decisions affecting the program will have wide-ranging consequences throughout the US safety net. Our scoping review provides a roadmap of the questions being asked about the 340B program and an initial synthesis of the answers. The highest-quality evidence indicates that nonprofit, disproportionate share hospitals may be using the 340B program in margin-motivated ways, with inconsistent evidence for increased safety net engagement; however, this finding is not consistent across other hospital types and public health clinics, which face different incentive structures and reporting requirements. CONTEXT: Despite remarkable growth and relevance of the 340B Drug Pricing Program to current health care practice and policy debate, academic literature examining 340B has lagged. The objectives of this scoping review were to summarize i) common research questions published about 340B, ii) what is empirically known about 340B and its implications, and iii) remaining knowledge gaps, all organized in a way that is informative to practitioners, researchers, and decision makers. METHODS: We conducted a scoping review of the peer-reviewed, empirical 340B literature (database inception to March 2023). We categorized studies by suitability of their design for internal validity, type of covered entity studied, and motivation-by-scope category. FINDINGS: The final yield included 44 peer-reviewed, empirical studies published between 2003 and 2023. We identified 15 frequently asked research questions in the literature, across 6 categories of inquiry-motivation (margin or mission) and scope (external, covered entity, and care delivery interface). Literature with greatest internal validity leaned toward evidence of margin-motivated behavior at the external environment and covered entity levels, with inconsistent findings supporting mission-motivated behavior at these levels; this was particularly the case among participating disproportionate share hospitals (DSHs). However, included case studies were unanimous in demonstrating positive effects of the 340B program for carrying out a provider's safety net mission. CONCLUSIONS: In our scoping review of the 340B program, the highest-quality evidence indicates nonprofit, DSHs may be using the 340B program in margin-motivated ways, with inconsistent evidence for increased safety net engagement; however, this finding is not consistent across other hospital types and public health clinics, which face different incentive structures and reporting requirements. Future studies should examine heterogeneity by covered entity types (i.e., hospitals vs. public health clinics), characteristics, and time period of 340B enrollment. Our findings provide additional context to current health policy discussion regarding the 340B program.


Assuntos
Custos de Medicamentos , Estados Unidos
5.
AIDS Behav ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375289

RESUMO

Despite advances in HIV care and treatment in the U.S., disparities in outcomes along the HIV care continuum persist. The widespread replication of effective and sustainable interventions that prioritize the engagement of underserved populations has been identified as a promising path to ending the HIV epidemic in the U.S. Intervention dissemination products, however, rarely provide the comprehensive and accessible information needed to replicate interventions within community settings. To bridge the divide between research and community-based implementation, the Using Evidence-informed Interventions to Improve Health Outcomes among People Living with HIV (E2i) initiative-grounded in the HIV/AIDS Bureau Implementation Science Framework-created a suite of tools to promote the rapid replication of interventions focused on transgender women, Black men who have sex with men, behavioral health integration, and identifying and addressing trauma. The resulting dissemination products are detailed and digestible multimedia toolkits that follow adult learning theory principles and align with the Template for Intervention Description and Replication criteria for adapting non-pharmacological interventions. Each E2i toolkit consists of five components: implementation guides, narrative videos of site implementation, best practice demonstration videos, interactive learning modules, and recruitment posters and brochures. Over 2 years (2022-2024), the E2i toolkit webpages amassed 7703 unique users and 17,666 pageviews. These toolkits can serve as a blueprint for designing comprehensive and accessible dissemination products for replication of HIV interventions in care settings. Dissemination products that bridge the gap between intervention research and replication in community settings are a crucial missing tool for ending the HIV epidemic.

6.
AIDS Behav ; 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38340221

RESUMO

The nationwide scale-up of evidence-based and evidence-informed interventions has been widely recognized as a crucial step in ending the HIV epidemic. Although the successful delivery of interventions may involve intensive expert training, technical assistance (TA), and dedicated funding, most organizations attempt to replicate interventions without access to focused expert guidance. Thus, there is a grave need for initiatives that meaningfully address HIV health disparities while addressing these inherent limitations. Here, the Health Resources and Services Administration HIV/AIDS Bureau (HRSA HAB) initiative Using Evidence-Informed Interventions to Improve HIV Health Outcomes among People Living with HIV (E2i) piloted an alternative approach to implementation that de-emphasized expert training to naturalistically simulate the experience of future HIV service organizations with limited access to TA. The E2i approach combined the HAB-adapted Institute for Healthcare Improvement's Breakthrough Series Collaborative Learning Model with HRSA HAB's Implementation Science Framework, to create an innovative multi-tiered system of peer-to-peer learning that was piloted across 11 evidence-informed interventions at 25 Ryan White HIV/AIDS Program sites. Four key types of peer-to-peer learning exchanges (i.e., intervention, site, staff role, and organization specific) took place at biannual peer learning sessions, while quarterly intervention cohort calls and E2i monthly calls with site staff occurred during the action periods between learning sessions. Peer-to-peer learning fostered both experiential learning and community building and allowed site staff to formulate robust site-specific action plans for rapid cycle testing between learning sessions. Strategies that increase the effectiveness of interventions while decreasing TA could provide a blueprint for the rapid uptake and integration of HIV interventions nationwide.

7.
Nature ; 558(7711): 610-614, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29925952

RESUMO

Viral infections continue to represent major challenges to public health, and an enhanced mechanistic understanding of the processes that contribute to viral life cycles is necessary for the development of new therapeutic strategies 1 . Viperin, a member of the radical S-adenosyl-L-methionine (SAM) superfamily of enzymes, is an interferon-inducible protein implicated in the inhibition of replication of a broad range of RNA and DNA viruses, including dengue virus, West Nile virus, hepatitis C virus, influenza A virus, rabies virus 2 and HIV3,4. Viperin has been suggested to elicit these broad antiviral activities through interactions with a large number of functionally unrelated host and viral proteins3,4. Here we demonstrate that viperin catalyses the conversion of cytidine triphosphate (CTP) to 3'-deoxy-3',4'-didehydro-CTP (ddhCTP), a previously undescribed biologically relevant molecule, via a SAM-dependent radical mechanism. We show that mammalian cells expressing viperin and macrophages stimulated with IFNα produce substantial quantities of ddhCTP. We also establish that ddhCTP acts as a chain terminator for the RNA-dependent RNA polymerases from multiple members of the Flavivirus genus, and show that ddhCTP directly inhibits replication of Zika virus in vivo. These findings suggest a partially unifying mechanism for the broad antiviral effects of viperin that is based on the intrinsic enzymatic properties of the protein and involves the generation of a naturally occurring replication-chain terminator encoded by mammalian genomes.


Assuntos
Antivirais/metabolismo , Citidina Trifosfato/metabolismo , Genoma Humano/genética , Proteínas/genética , Proteínas/metabolismo , Terminação da Transcrição Genética , Animais , Antivirais/química , Chlorocebus aethiops , Citidina Trifosfato/biossíntese , Citidina Trifosfato/química , Células HEK293 , Humanos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , RNA Polimerase Dependente de RNA/antagonistas & inibidores , RNA Polimerase Dependente de RNA/metabolismo , Ribonucleotídeos , Especificidade por Substrato , Células Vero , Zika virus/enzimologia , Zika virus/metabolismo
8.
Nature ; 562(7725): E3, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29980769

RESUMO

Change history: In the HTML version of this Letter, Extended Data Fig. 4 incorrectly corresponded to Fig. 4 (the PDF version of the figure was correct). This has been corrected online.

9.
J Am Soc Nephrol ; 34(4): 682-693, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36735807

RESUMO

SIGNIFICANCE STATEMENT: Studies discusses CKD disparities by age, race and ethnicity, and socioeconomics. However, despite well-documented disparities in CKD risk factors in LGBT+ adults, limited literature addresses CKD prevalence in this population. This analysis uses Behavioral Risk Factor Surveillance System (2014-2019) data to compare self-reported kidney disease prevalence in LGBT+ older adults (older than 50 years) with their heterosexual peers. Our findings indicate that LGBT+ older adults have higher rates of self-reported kidney disease and a higher incidence of CKD risks including smoking, activity limitations, adverse health outcomes, and limited access to health care, housing, and employment. These results support increasing access to screening for CKD risk factors, providing culturally responsive health care, and addressing societal drivers of vulnerability in older LGBT+ adults. BACKGROUND: Existing research documents disparities in CKD by age, race and ethnicity, and access to health care. However, research on CKD in lesbian, gay, bisexual, and trans (LGBT+) older adults, despite their higher rates of diabetes, heart disease, smoking, and alcohol use, is limited. METHODS: Pooled data from the Behavioral Risk Factor Surveillance System (2014-2019) for 22,114 LGBT+ adults and 748,963 heterosexuals aged 50 and older were used to estimate the prevalence of self-reported kidney disease. Logistic regressions were used to compare older adults by sexual orientation. RESULTS: Older LGBT+ men (adjusted odds ratio=1.3; 95% confidence interval [CI], 1.09-1.54) were more likely than their heterosexual counterparts to report kidney disease, after controlling for sociodemographic factors, health behaviors, access to health care, and self-reported coronary heart disease, HIV, and diabetes; LGBT+ men and women also reported higher incidences of known risk factors for CKD. For example, both LGBT+ men (odds ratio [OR]=1.39; [95% CI], 1.26-1.54) and LGBT+ women (OR=1.39; [95% CI], 1.25-1.55) were more likely to be smokers and have a higher incidence of activity limitations, adverse health outcomes, and limited access to health care, housing, and employment. CONCLUSION: These results support increasing access to screenings for CKD risk factors, providing preventative education and culturally responsive and affirming care, and addressing other societal drivers of vulnerability in older LGBT+ adults. The findings also support the value of interventions that address the interaction between CKD risk factors and the social marginalization that older LGBT+ adults experience.


Assuntos
Diabetes Mellitus , Insuficiência Renal Crônica , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Sistema de Vigilância de Fator de Risco Comportamental , Autorrelato , Prevalência , Comportamento Sexual , Insuficiência Renal Crônica/epidemiologia
10.
Heredity (Edinb) ; 130(3): 135-144, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36639700

RESUMO

European wildlife has been subjected to intensifying levels of anthropogenic impact throughout the Holocene, yet the main genetic partitioning of many species is thought to still reflect the late-Pleistocene glacial refugia. We analyzed 26,342 nuclear SNPs of 464 wild boar (Sus scrofa) across the European continent to infer demographic history and reassess the genetic consequences of natural and anthropogenic forces. We found that population fragmentation, inbreeding and recent hybridization with domestic pigs have caused the spatial genetic structure to be heterogeneous at the local scale. Underlying local anthropogenic signatures, we found a deep genetic structure in the form of an arch-shaped cline extending from the Dinaric Alps, via Southeastern Europe and the Baltic states, to Western Europe and, finally, to the genetically diverged Iberian peninsula. These findings indicate that, despite considerable anthropogenic influence, the deeper, natural continental structure is still intact. Regarding the glacial refugia, our findings show a weaker signal than generally assumed, but are nevertheless suggestive of two main recolonization routes, with important roles for Southern France and the Balkans. Our results highlight the importance of applying genomic resources and framing genetic results within a species' demographic history and geographic distribution for a better understanding of the complex mixture of underlying processes.


Assuntos
Variação Genética , Genoma , Animais , Suínos , Europa (Continente) , Demografia , Sus scrofa/genética , Filogenia , DNA Mitocondrial/genética
11.
J Aging Soc Policy ; : 1-13, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37348486

RESUMO

Sexual and gender minority (SGM) older adults face discrimination in long-term services and supports (LTSS). Yet, SGM older adults use LTSS disproportionately higher relative to their non-SGM counterparts. The discrimination is compounded by existing disparities, resulting in worse health outcomes and well-being for SGM older adults. Guided by socioecological model, we posit that training LTSS staff in SGM responsive care and implementing SGM anti-discrimination policies will be needed to improve care. Considering accessibility and turnover challenges, training should be online, interactive, and easily accessible. Studies that assess interventions for SGM responsive care are needed to guide policy and practice.

12.
AIDS Care ; 34(4): 505-514, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34612097

RESUMO

Traumatic experiences are disproportionately prevalent among people with HIV and adversely affect HIV-related health outcomes. As part of a national cooperative agreement funded by the Health Resources and Services Administration's HIV/AIDS Bureau, we searched the literature for interventions designed to address trauma among people with HIV in the U.S. Our search yielded 22 articles on 14 studies that fell into five intervention categories: expressive writing, prolonged exposure therapy, coping skills, cognitive-behavioral approaches integrated with other methods, and trauma-informed care. Thematic elements among the interventions included adaptating existing interventions for subpopulations with a high burden of trauma and HIV, such as transgender women and racial/ethnic minorities; addressing comorbid substance use disorders; and implementing organization-wide trauma-informed care approaches. Few studies measured the effect of the interventions on HIV-related health outcomes. To address the intersecting epidemics of HIV and trauma, it is critical to continue developing, piloting, and evaluating trauma interventions for people with HIV, with the goal of wide-scale replication of effective interventions in HIV settings.


Assuntos
Síndrome da Imunodeficiência Adquirida , Terapia Cognitivo-Comportamental , Infecções por HIV , Transexualidade , Adaptação Psicológica , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/terapia , Humanos
13.
Aging Ment Health ; 26(9): 1845-1854, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34784488

RESUMO

OBJECTIVE: LGBT older adults and older people living with HIV (PLWH) experience a disproportionate burden of behavioral health conditions compared to their heterosexual, cisgender, and HIV-negative peers. This study intends to systematically review the literature regarding accessing mental health care among LGBT older adults and older PLWH. METHODS: This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement framework. Three databases were searched using Boolean search strings, and inclusion/exclusion criteria were developed and applied to the search outcomes to appropriately narrow results. Article quality and evidence of bias were evaluated using the National Heart, Lung, and Blood Institute (NHLBI) quality-assessment tool, and the Critical Appraisal Skills Program (CASP) assessment tool, two instruments used to help reviewers in assessing for internal validity of studies. Two independent researchers coded the articles for themes, and consensus was reached on theme grouping through an iterative process. RESULTS: Out of 2,031 articles initially screened, 28 met all inclusion criteria and advanced to final analysis. Several key themes emerged, including a lack of provider competency in caring for LGBT patients, lower rates of insurance coverage, greater mental health burden, social and structural determinants of health, policy solutions, and technology and health literacy. CONCLUSION: There were several domains identified in the literature as barriers to accessing mental healthcare, as well as opportunities to better attend to the mental health needs of these populations. Provider training, implementing health technology solutions, and enacting public policy changes could improve mental health outcomes.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Idoso , Infecções por HIV/terapia , Acessibilidade aos Serviços de Saúde , Humanos , Saúde Mental , Inquéritos e Questionários
14.
Harm Reduct J ; 19(1): 73, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35790994

RESUMO

BACKGROUND: Safe consumption sites (SCSs) serve diverse populations of people who use drugs (PWUD) and public health objectives. SCS implementation began in the 1980s, and today, there are at least 200 known SCSs operating in over twelve countries. While a growing literature supports their effectiveness as a harm reduction strategy, there is limited information on contextual factors that may support or hinder SCS implementation and sustainability. We aimed to fill this gap in knowledge by reviewing existing qualitative studies on SCSs. METHODS: We conducted a systematic review and thematic synthesis of qualitative studies. We identified all peer-reviewed, English-language qualitative studies on SCSs containing original data in PubMed, Web of Science, Google Scholar, and Science Direct as of September 23, 2019. Two authors independently screened, abstracted, and coded content relating to SCS implementation and sustainment aligned with the Exploration, Preparation, Implementation, Sustainment (EPIS) implementation science framework. RESULTS: After removing duplicates, we identified 765 unique records, of which ten qualitative studies met inclusion criteria for our synthesis. Across these ten studies, 236 total interviews were conducted. Overall, studies described how SCSs can (1) keep drug use out of public view while fostering a sense of inclusion for participants, (2) support sustainment by enhancing external communities' acceptability of SCSs, and (3) encourage PWUD utilization. Most studies also described how involving PWUD and peer workers (i.e., those with lived experience) in SCS operation supported implementation and sustainability. DISCUSSION: Our thematic synthesis of qualitative literature identified engagement of PWUD and additional factors that appear to support SCS planning and operations and are critical to implementation success. However, the existing qualitative literature largely lacked perspectives of SCS staff and other community members who might be able to provide additional insight into factors influencing the implementation and sustainability of this promising public health intervention.


Assuntos
Redução do Dano , Transtornos Relacionados ao Uso de Substâncias , Humanos , Ciência da Implementação , Saúde Pública , Pesquisa Qualitativa
15.
Biochemistry ; 60(10): 791-801, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33656855

RESUMO

S-Adenosyl-l-methionine (AdoMet) is synthesized by the MAT2A isozyme of methionine adenosyltransferase in most human tissues and in cancers. Its contribution to epigenetic control has made it a target for anticancer intervention. A recent kinetic isotope effect analysis of MAT2A demonstrated a loose nucleophilic transition state. Here we show that MAT2A has a sequential mechanism with a rate-limiting step of formation of AdoMet, followed by rapid hydrolysis of the ß-γ bond of triphosphate, and rapid release of phosphate and pyrophosphate. MAT2A catalyzes the slow hydrolysis of both ATP and triphosphate in the absence of other reactants. Positional isotope exchange occurs with 18O as the 5'-oxygen of ATP. Loss of the triphosphate is sufficiently reversible to permit rotation and recombination of the α-phosphoryl group of ATP. Adenosine (α-ß or ß-γ)-imido triphosphates are slow substrates, and the respective imido triphosphates are inhibitors. The hydrolytically stable (α-ß, ß-γ)-diimido triphosphate (PNPNP) is a nanomolar inhibitor. The MAT2A protein structure is highly stabilized against denaturation by binding of PNPNP. A crystal structure of MAT2A with 5'-methylthioadenosine and PNPNP shows the ligands arranged appropriately in the ATP binding site. Two magnesium ions chelate the α- and γ-phosphoryl groups of PNPNP. The ß-phosphoryl oxygen is in contact with an essential potassium ion. Imidophosphate derivatives provide contact models for the design of catalytic site ligands for MAT2A.


Assuntos
Trifosfato de Adenosina/metabolismo , Difosfatos/metabolismo , Inibidores Enzimáticos/farmacologia , Metionina Adenosiltransferase/antagonistas & inibidores , Metionina Adenosiltransferase/metabolismo , Polifosfatos/metabolismo , S-Adenosilmetionina/farmacologia , Sítios de Ligação , Humanos , Hidrólise , Cinética , Conformação Proteica
16.
J Am Chem Soc ; 143(43): 18325-18330, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34668717

RESUMO

Human methionine adenosyltransferase MAT2A provides S-adenosyl-l-methionine (AdoMet) for methyl-transfer reactions. Epigenetic methylations influence expression patterns in development and in cancer. Transition-state analysis and kinetic studies have described the mechanism of AdoMet and triphosphate formation at the catalytic site. Hydrolysis of triphosphate to pyrophosphate and phosphate by MAT2A is required for product release and proceeds through a second chemical transition state. Crystal structures of MAT2A with analogues of AdoMet and pyrophosphate were obtained in the presence of Mg2+, Al3+, and F-. MgF3- is trapped as a PO3- mimic in a structure with malonate filling the pyrophosphate site. NMR demonstrates that MgF3- and AlF30 are bound by MAT2A as mimics of the departing phosphoryl group. Crystallographic analysis reveals a planar MgF3- acting to mimic a phosphoryl (PO3-) leaving group. The modeled transition state with PO3- has the phosphorus atom sandwiched symmetrically and equidistant (approximately 2 Å) between a pyrophosphate oxygen and the water nucleophile. A catalytic site arginine directs the nucleophilic water to the phosphoryl leaving group. The catalytic geometry of the transition-state reconstruction predicts a loose transition state with characteristics of symmetric nucleophilic displacement.


Assuntos
Biocatálise , Metionina Adenosiltransferase/metabolismo , Polifosfatos/metabolismo , Domínio Catalítico , Cristalografia por Raios X , Humanos , Hidrólise , Metionina Adenosiltransferase/química , Modelos Químicos , Polifosfatos/química , Ligação Proteica , Água/metabolismo
17.
Am J Public Health ; 111(11): 2059-2063, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34499534

RESUMO

Objectives. To examine the relationship between city-level structural stigma pertaining to sexual orientation and gender identity (SOGI) and completeness of patient SOGI data collection at US federally qualified health centers (FQHCs). Methods. We used the Human Rights Campaign's Municipal Equality Index to quantify city-level structural stigma against sexual and gender minority people in 506 US cities across 49 states. We ascertained the completeness of SOGI data collection at FQHCs from the 2018 Uniform Data System, which describes FQHC patient demographics and service utilization. We included FQHCs in cities captured by the structural stigma index in multinomial generalized linear mixed models to examine the relationship between city-level structural stigma and SOGI data completeness. Results. FQHCs in cities with more protective sexual orientation nondiscrimination policies reported more complete patient sexual orientation data (adjusted odds ratio [AOR] = 1.6; 95% confidence interval [CI] = 1.2, 2.1). This association was also found for gender identity nondiscrimination policies and gender identity data collection (AOR = 1.7; 95% CI = 1.3, 2.2). Conclusions. Municipal sexual and gender minority nondiscrimination laws are associated with social and municipal environments that facilitate patient SOGI data collection.(Am J Public Health. 2021;111(11):2059-2063. https://doi.org/10.2105/AJPH.2021.306414).


Assuntos
Identidade de Gênero , Preconceito/legislação & jurisprudência , Comportamento Sexual , Estigma Social , Cidades , Feminino , Humanos , Masculino , Inquéritos e Questionários , Estados Unidos
18.
AIDS Care ; 32(5): 585-593, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31482726

RESUMO

Transgender women (TW) are disproportionately affected by HIV. Antiretroviral pre-exposure prophylaxis (PrEP) can reduce TW's vulnerability to HIV, but PrEP uptake has been limited among TW. To explore barriers to PrEP uptake, the study team conducted two semi-structured focus groups with TW in San Francisco at risk for HIV acquisition. A within-case, across-case approach was used to code and analyze emerging themes. Focus group participants were racially and ethnically diverse. A few participants in both groups had heard of PrEP, but some had not. Several said that their health care providers had not told them about PrEP. Participants in both groups had questions about side effects. They expressed medical mistrust and said poverty is an important context for their lives. They described a need for gender affirming health care services and raised concerns about interactions of PrEP with feminizing hormones. Information about side effects and interactions between gender affirming hormones and PrEP need to be explicitly addressed in PrEP education campaigns focusing on TW. Health care institutions and health departments should train clinical staff how to provide affirming care. Gender identity nondiscrimination laws and policies could improve transgender people's ability to earn a living and access health care.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Profilaxia Pré-Exposição/métodos , Pessoas Transgênero/psicologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Feminino , Grupos Focais , Identidade de Gênero , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , São Francisco , Confiança
19.
J Pediatr Orthop ; 40(9): 536-542, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32555043

RESUMO

BACKGROUND: Ligamentous laxity testing using the Beighton score is frequently used as part of the pediatric shoulder examination. However, the relationship between generalized ligamentous laxity (GLL) and shoulder range of motion (ROM) remains unexamined in children, and normative data for these clinical tests have not been well established. In this study, we establish normative data for shoulder range of motion and GLL in a healthy, diverse pediatric population and investigate whether Beighton testing correlates with shoulder ROM in children. METHODS: Healthy subjects age 2 to 18 years with isolated lower extremity complaints were recruited. Passive shoulder ROM measurements for forward flexion (FF), abduction (ABD), internal rotation (IR), external rotation (ER), and extension (EXT) were obtained using a long-armed goniometer. The Beighton score was obtained, with a positive test defined as ≥5. Descriptive statistics were used to stratify data on the basis of age and sex. Interclass correlation coefficients (ICCs) were calculated. Spearman's r was calculated to determine correlations between the Beighton score and shoulder ROM. Predictive indices of a positive Beighton test to identify patients with high shoulder mobility (ROM in the top 15 percentile, or 1 SD above the mean) were calculated. RESULTS: A total of 202 subjects were enrolled and evaluated. Passive ROM norms by age and sex were determined. Intraclass correlation coefficients for all shoulder ROM measurements were substantial to excellent. Female individuals had greater ROM than age-matched male individuals, but this trend was largely statistically insignificant. Pearson's correlation between age and shoulder ROM was significant for FF, ABD, EXT, and ER (r=-0.52 to -0.20, P<0.001). Based on a Beighton score of ≥5, the prevalence of GLL was 10% in male and 15% in female individuals. Spearman's correlation between Beighton score and shoulder ROM was significant for 3 of 5 ROM measurements: FF, ER, and EXT (r=0.30 to 0.39, P<0.001). CONCLUSIONS: Normative pediatric shoulder ROM and joint laxity data have been established in a healthy, diverse population of children. Beighton testing exhibits only a weak to moderate correlation, despite statistical significance, with shoulder ROM and is poorly predictive for high ROM in children. LEVEL OF EVIDENCE: Level I- Diagnostic.


Assuntos
Amplitude de Movimento Articular/fisiologia , Articulação do Ombro/fisiologia , Ombro/fisiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pediatria/normas , Valores de Referência , Estados Unidos
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