Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 16.427
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Cell ; 187(1): 17-43, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38181740

RESUMO

Although social interactions are known to drive pathogen transmission, the contributions of socially transmissible host-associated mutualists and commensals to host health and disease remain poorly explored. We use the concept of the social microbiome-the microbial metacommunity of a social network of hosts-to analyze the implications of social microbial transmission for host health and disease. We investigate the contributions of socially transmissible microbes to both eco-evolutionary microbiome community processes (colonization resistance, the evolution of virulence, and reactions to ecological disturbance) and microbial transmission-based processes (transmission of microbes with metabolic and immune effects, inter-specific transmission, transmission of antibiotic-resistant microbes, and transmission of viruses). We consider the implications of social microbial transmission for communicable and non-communicable diseases and evaluate the importance of a socially transmissible component underlying canonically non-communicable diseases. The social transmission of mutualists and commensals may play a significant, under-appreciated role in the social determinants of health and may act as a hidden force in social evolution.


Assuntos
Microbiota , Fatores Sociais , Simbiose , Animais , Humanos , Doenças não Transmissíveis , Virulência
2.
Cell ; 186(9): 1863-1876.e16, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37030292

RESUMO

Over the past few years, numerous anti-phage defense systems have been discovered in bacteria. Although the mechanism of defense for some of these systems is understood, a major unanswered question is how these systems sense phage infection. To systematically address this question, we isolated 177 phage mutants that escape 15 different defense systems. In many cases, these escaper phages were mutated in the gene sensed by the defense system, enabling us to map the phage determinants that confer sensitivity to bacterial immunity. Our data identify specificity determinants of diverse retron systems and reveal phage-encoded triggers for multiple abortive infection systems. We find general themes in phage sensing and demonstrate that mechanistically diverse systems have converged to sense either the core replication machinery of the phage, phage structural components, or host takeover mechanisms. Combining our data with previous findings, we formulate key principles on how bacterial immune systems sense phage invaders.


Assuntos
Bactérias , Bacteriófagos , Bactérias/genética , Bactérias/virologia , Bacteriófagos/genética , Sistemas CRISPR-Cas , Proteínas Virais/metabolismo , Mutação , Fenômenos Fisiológicos Bacterianos
3.
CA Cancer J Clin ; 73(5): 461-479, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37329257

RESUMO

There remains a need to synthesize linkages between social determinants of health (SDOH) and cancer screening to reduce persistent inequities contributing to the US cancer burden. The authors conducted a systematic review of US-based breast, cervical, colorectal, and lung cancer screening intervention studies to summarize how SDOH have been considered in interventions and relationships between SDOH and screening. Five databases were searched for peer-reviewed research articles published in English between 2010 and 2021. The Covidence software platform was used to screen articles and extract data using a standardized template. Data items included study and intervention characteristics, SDOH intervention components and measures, and screening outcomes. The findings were summarized using descriptive statistics and narratives. The review included 144 studies among diverse population groups. SDOH interventions increased screening rates overall by a median of 8.4 percentage points (interquartile interval, 1.8-18.8 percentage points). The objective of most interventions was to increase community demand (90.3%) and access (84.0%) to screening. SDOH interventions related to health care access and quality were most prevalent (227 unique intervention components). Other SDOH, including educational, social/community, environmental, and economic factors, were less common (90, 52, 21, and zero intervention components, respectively). Studies that included analyses of health policy, access to care, and lower costs yielded the largest proportions of favorable associations with screening outcomes. SDOH were predominantly measured at the individual level. This review describes how SDOH have been considered in the design and evaluation of cancer screening interventions and effect sizes for SDOH interventions. Findings may guide future intervention and implementation research aiming to reduce US screening inequities.


Assuntos
Neoplasias Pulmonares , Determinantes Sociais da Saúde , Humanos , Detecção Precoce de Câncer , Disparidades nos Níveis de Saúde , Escolaridade
4.
Am J Hum Genet ; 111(5): 809-824, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38642557

RESUMO

Advancements in genomic technologies have shown remarkable promise for improving health trajectories. The Human Genome Project has catalyzed the integration of genomic tools into clinical practice, such as disease risk assessment, prenatal testing and reproductive genomics, cancer diagnostics and prognostication, and therapeutic decision making. Despite the promise of genomic technologies, their full potential remains untapped without including individuals of diverse ancestries and integrating social determinants of health (SDOHs). The NHGRI launched the 2020 Strategic Vision with ten bold predictions by 2030, including "individuals from ancestrally diverse backgrounds will benefit equitably from advances in human genomics." Meeting this goal requires a holistic approach that brings together genomic advancements with careful consideration to healthcare access as well as SDOHs to ensure that translation of genetics research is inclusive, affordable, and accessible and ultimately narrows rather than widens health disparities. With this prediction in mind, this review delves into the two paramount applications of genetic testing-reproductive genomics and precision oncology. When discussing these applications of genomic advancements, we evaluate current accessibility limitations, highlight challenges in achieving representativeness, and propose paths forward to realize the ultimate goal of their equitable applications.


Assuntos
Genômica , Medicina de Precisão , Humanos , Genômica/métodos , Medicina de Precisão/métodos , Genoma Humano , Testes Genéticos , Neoplasias/genética , Acessibilidade aos Serviços de Saúde
5.
CA Cancer J Clin ; 70(1): 31-46, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31661164

RESUMO

Although cancer mortality rates declined in the United States in recent decades, some populations experienced little benefit from advances in cancer prevention, early detection, treatment, and survivorship care. In fact, some cancer disparities between populations of low and high socioeconomic status widened during this period. Many potentially preventable cancer deaths continue to occur, and disadvantaged populations bear a disproportionate burden. Reducing the burden of cancer and eliminating cancer-related disparities will require more focused and coordinated action across multiple sectors and in partnership with communities. This article, part of the American Cancer Society's Cancer Control Blueprint series, introduces a framework for understanding and addressing social determinants to advance cancer health equity and presents actionable recommendations for practice, research, and policy. The article aims to accelerate progress toward eliminating disparities in cancer and achieving health equity.


Assuntos
Equidade em Saúde/normas , Política de Saúde , Disparidades nos Níveis de Saúde , Neoplasias/epidemiologia , Determinantes Sociais da Saúde/normas , Terapia Combinada , Saúde Global , Humanos , Morbidade/tendências , Neoplasias/terapia , Taxa de Sobrevida/tendências
6.
Proc Natl Acad Sci U S A ; 121(30): e2404108121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39008669

RESUMO

Low socioeconomic status (SES) is a risk factor for mortality and immune dysfunction across a wide range of diseases, including cancer. However, cancer is distinct in the use of allogeneic hematopoietic cell transplantation (HCT) as a treatment for hematologic malignancies to transfer healthy hematopoietic cells from one person to another. This raises the question of whether social disadvantage of an HCT cell donor, as assessed by low SES, might impact the subsequent health outcomes of the HCT recipient. To evaluate the cellular transplantability of SES-associated health risk, we analyzed the health outcomes of 2,005 HCT recipients who were transplanted for hematologic malignancy at 125 United States transplant centers and tested whether their outcomes differed as a function of their cell donor's SES (controlling for other known HCT-related risk factors). Recipients transplanted with cells from donors in the lowest quartile of SES experienced a 9.7% reduction in overall survival (P = 0.001) and 6.6% increase in treatment-related mortality within 3 y (P = 0.008) compared to those transplanted from donors in the highest SES quartile. These results are consistent with previous research linking socioeconomic disadvantage to altered immune cell function and hematopoiesis, and they reveal an unanticipated persistence of those effects after cells are transferred into a new host environment. These SES-related disparities in health outcomes underscore the need to map the biological mechanisms involved in the social determinants of health and develop interventions to block those effects and enhance the health of both HCT donors and recipients.


Assuntos
Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/mortalidade , Fatores de Risco , Classe Social , Estados Unidos/epidemiologia , Idoso , Adolescente , Doadores de Tecidos
7.
Bioessays ; 46(1): e2300179, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37983969

RESUMO

Fertilization triggers cytoplasmic movements in the frog egg that lead in mysterious ways to the stabilization of ß-catenin on the dorsal side of the embryo. The novel Huluwa (Hwa) transmembrane protein, identified in China, is translated specifically in the dorsal side, acting as an egg cytoplasmic determinant essential for ß-catenin stabilization. The Wnt signaling pathway requires macropinocytosis and the sequestration inside multivesicular bodies (MVBs, the precursors of endolysosomes) of Axin1 and Glycogen Synthase Kinase 3 (GSK3) that normally destroy ß-catenin. In Xenopus, the Wnt-like activity of GSK3 inhibitors and of Hwa mRNA can be blocked by brief treatment with inhibitors of membrane trafficking or lysosomes at the 32-cell stage. In dorsal blastomeres, lysosomal cathepsin is activated and intriguing MVBs surrounded by electron dense vesicles are formed at the 64-cell stage. We conclude that membrane trafficking and lysosomal activity are critically important for the earliest asymmetries in vertebrate embryonic development.


Assuntos
Quinase 3 da Glicogênio Sintase , beta Catenina , Animais , Quinase 3 da Glicogênio Sintase/metabolismo , Endossomos/metabolismo , Lisossomos/metabolismo , Xenopus laevis/genética
8.
Proc Natl Acad Sci U S A ; 120(7): e2209414120, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36749720

RESUMO

While social characteristics are well-known predictors of mortality, prediction models rely almost exclusively on demographics, medical comorbidities, and function. Lacking an efficient way to summarize the prognostic impact of social factor, many studies exclude social factors altogether. Our objective was to develop and validate a summary measure of social risk and determine its ability to risk-stratify beyond traditional risk models. We examined participants in the Health and Retirement Study, a longitudinal, survey of US older adults. We developed the model from a comprehensive inventory of 183 social characteristics using least absolute shrinkage and selection operator, a penalized regression approach. Then, we assessed the predictive capacity of the model and its ability to improve on traditional prediction models. We studied 8,250 adults aged ≥65 y. Within 4 y of the baseline interview, 22% had died. Drawn from 183 possible predictors, the Social Frailty Index included age, gender, and eight social predictors: neighborhood cleanliness, perceived control over financial situation, meeting with children less than yearly, not working for pay, active with children, volunteering, feeling isolated, and being treated with less courtesy or respect. In the validation cohort, predicted and observed mortality were strongly correlated. Additionally, the Social Frailty Index meaningfully risk-stratified participants beyond the Charlson score (medical comorbidity index) and the Lee Index (comorbidity and function model). The Social Frailty Index includes age, gender, and eight social characteristics and accurately risk-stratifies older adults. The model improves upon commonly used risk prediction tools and has application in clinical, population health, and research settings.


Assuntos
Fragilidade , Criança , Humanos , Idoso , Estudos Longitudinais , Aposentadoria , Fatores Sociológicos
9.
Proc Natl Acad Sci U S A ; 120(16): e2211755120, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37043532

RESUMO

Sustained life stress and low socioeconomic status are among the major causes of aging-related diseases and decreased life expectancy. Experimental rodent models can help to identify the underlying mechanisms, yet very few studies address the long-term consequences of social stress on aging. We conducted a randomized study involving more than 300 male mice of commonly used laboratory strains (C57BL/6J, CD1, and Sv129Ev) chosen for the spontaneous aggression gradient and stress-vulnerability. Mice were exposed to a lifelong chronic psychosocial stress protocol to model social gradients in aging and disease vulnerability. Low social rank, inferred based on a discretized aggression index, was found to negatively impact lifespan in our study population. However, social rank interacted with genetic background in that low-ranking C57BL/6J, high-ranking Sv129Ev, and middle-ranking CD1 mice had lower survival, respectively, implying a cost of maintaining a given social rank that varies across strains. Machine learning linear discriminant analysis identified baseline fat-free mass as the most important predictor of mouse genetic background and social rank in the present dataset. Finally, strain and social rank differences were significantly associated with epigenetic changes, most significantly in Sv129Ev mice and in high-ranking compared to lower ranking subjects. Overall, we identified genetic background and social rank as critical contextual modifiers of aging and lifespan in an ethologically relevant rodent model of social stress, thereby providing a preclinical experimental paradigm to study the impact of social determinants of health disparities and accelerated aging.


Assuntos
Epigenoma , Longevidade , Animais , Humanos , Masculino , Camundongos , Envelhecimento/genética , Longevidade/genética , Camundongos Endogâmicos C57BL , Estresse Psicológico/genética
10.
J Biol Chem ; 300(5): 107219, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522516

RESUMO

G-protein-gated inward rectifier K+ (GIRK) channels play a critical role in the regulation of the excitability of cardiomyocytes and neurons and include GIRK1, GIRK2, GIRK3 and GIRK4 subfamily members. BD1047 dihydrobromide (BD1047) is one of the representative antagonists of the multifunctional Sigma-1 receptor (S1R). In the analysis of the effect of BD1047 on the regulation of Gi-coupled receptors by S1R using GIRK channel as an effector, we observed that BD1047, as well as BD1063, directly inhibited GIRK currents even in the absence of S1R and in a voltage-independent manner. Thus, we aimed to clarify the effect of BD1047 on GIRK channels and identify the structural determinants. By electrophysiological recordings in Xenopus oocytes, we observed that BD1047 directly inhibited GIRK channel currents, producing a much stronger inhibition of GIRK4 compared to GIRK2. It also inhibited ACh-induced native GIRK current in isolated rat atrial myocytes. Chimeric and mutagenesis studies of GIRK2 and GIRK4 combined with molecular docking analysis demonstrated the importance of Leu77 and Leu84 within the cytoplasmic, proximal N-terminal region and Glu147 within the pore-forming region of GIRK4 for inhibition by BD1047. The activator of GIRK channels, ivermectin, competed with BD1047 at Leu77 on GIRK4. This study provides us with a novel inhibitor of GIRK channels and information for developing pharmacological treatments for GIRK4-associated diseases.


Assuntos
Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G , Receptores sigma , Receptor Sigma-1 , Animais , Ratos , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genética , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/química , Simulação de Acoplamento Molecular , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Oócitos/metabolismo , Receptores sigma/metabolismo , Receptores sigma/antagonistas & inibidores , Receptores sigma/genética , Receptores sigma/química , Xenopus laevis , Ratos Wistar
11.
Circulation ; 150(3): 203-214, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38934130

RESUMO

BACKGROUND: Proximity to urban blue and green spaces has been associated with improved cardiovascular health; however, few studies have examined the role of race and socioeconomic status in these associations. METHODS: Data were from the CARDIA study (Coronary Artery Risk Development in Young Adults). We included longitudinal measurements (1985-1986 to 2010-2011) of blue and green spaces, including percentage of blue space cover, distance to the nearest river, green space cover, and distance to the nearest major park. Presence of coronary artery calcification (CAC) was measured with noncontrast cardiac computed tomography in 2010 to 2011. The associations of blue and green spaces with CAC were assessed with generalized estimating equation regression with adjustment for demographics, individual and neighborhood socioeconomic status, health-related behaviors, and other health conditions. We conducted stratified analyses by race and neighborhood deprivation score to investigate whether the association varied according to social determinants of health. RESULTS: The analytic sample included 1365 Black and 1555 White participants with a mean±SD age of 50.1±3.6 years. Among Black participants, shorter distance to a river and greater green space cover were associated with lower odds of CAC (per interquartile range decrease [1.45 km] to the river: odds ratio [OR], 0.90 [95% CI, 0.84-0.96]; per 10 percentage-point increase of green space cover: OR, 0.85 [95% CI, 0.75-0.95]). Among participants in deprived neighborhoods, greater green space cover was associated with lower odds of CAC (per a 10 percentage-point increase: OR, 0.89 [95% CI, 0.80-0.99]), whereas shorter distance to the park was associated with higher odds of CAC (per an interquartile range decrease [5.3 km]: OR, 1.07 [95% CI, 1.00-1.15]). Black participants in deprived neighborhoods had lower odds of CAC with shorter distance to a river (per an interquartile range decrease: OR, 0.90 [95% CI, 0.82-0.98]) and greater green space cover (per a 10 percentage-point increase: OR, 0.85 [95% CI, 0.75-0.97]). There was no statistical interaction between the blue and green spaces and race or neighborhood characteristics in association with CAC. CONCLUSIONS: Longitudinally, shorter distance to a river and greater green space cover were associated with less CAC among Black participants and those in deprived neighborhoods. Shorter distance to a park was associated with increased odds of CAC among participants in deprived neighborhoods. Black participants residing in more deprived neighborhoods showed lower odds of CAC in association with greater exposure to river and green space cover.


Assuntos
Negro ou Afro-Americano , Doença da Artéria Coronariana , Calcificação Vascular , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/etnologia , Doença da Artéria Coronariana/epidemiologia , Adulto , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/etnologia , Calcificação Vascular/epidemiologia , População Branca , Fatores de Risco , Características da Vizinhança , Características de Residência , Estudos Longitudinais , População Urbana , Populações Vulneráveis , Parques Recreativos
12.
Circulation ; 149(6): 430-449, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-37947085

RESUMO

BACKGROUND: Multivariable equations are recommended by primary prevention guidelines to assess absolute risk of cardiovascular disease (CVD). However, current equations have several limitations. Therefore, we developed and validated the American Heart Association Predicting Risk of CVD EVENTs (PREVENT) equations among US adults 30 to 79 years of age without known CVD. METHODS: The derivation sample included individual-level participant data from 25 data sets (N=3 281 919) between 1992 and 2017. The primary outcome was CVD (atherosclerotic CVD and heart failure). Predictors included traditional risk factors (smoking status, systolic blood pressure, cholesterol, antihypertensive or statin use, and diabetes) and estimated glomerular filtration rate. Models were sex-specific, race-free, developed on the age scale, and adjusted for competing risk of non-CVD death. Analyses were conducted in each data set and meta-analyzed. Discrimination was assessed using the Harrell C-statistic. Calibration was calculated as the slope of the observed versus predicted risk by decile. Additional equations to predict each CVD subtype (atherosclerotic CVD and heart failure) and include optional predictors (urine albumin-to-creatinine ratio and hemoglobin A1c), and social deprivation index were also developed. External validation was performed in 3 330 085 participants from 21 additional data sets. RESULTS: Among 6 612 004 adults included, mean±SD age was 53±12 years, and 56% were women. Over a mean±SD follow-up of 4.8±3.1 years, there were 211 515 incident total CVD events. The median C-statistics in external validation for CVD were 0.794 (interquartile interval, 0.763-0.809) in female and 0.757 (0.727-0.778) in male participants. The calibration slopes were 1.03 (interquartile interval, 0.81-1.16) and 0.94 (0.81-1.13) among female and male participants, respectively. Similar estimates for discrimination and calibration were observed for atherosclerotic CVD- and heart failure-specific models. The improvement in discrimination was small but statistically significant when urine albumin-to-creatinine ratio, hemoglobin A1c, and social deprivation index were added together to the base model to total CVD (ΔC-statistic [interquartile interval] 0.004 [0.004-0.005] and 0.005 [0.004-0.007] among female and male participants, respectively). Calibration improved significantly when the urine albumin-to-creatinine ratio was added to the base model among those with marked albuminuria (>300 mg/g; 1.05 [0.84-1.20] versus 1.39 [1.14-1.65]; P=0.01). CONCLUSIONS: PREVENT equations accurately and precisely predicted risk for incident CVD and CVD subtypes in a large, diverse, and contemporary sample of US adults by using routinely available clinical variables.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Insuficiência Cardíaca , Adulto , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Creatinina , Hemoglobinas Glicadas , American Heart Association , Fatores de Risco , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Albuminas , Medição de Risco
13.
Circulation ; 149(6): e312-e329, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38226471

RESUMO

During the COVID-19 pandemic, the American Heart Association created a new 2024 Impact Goal with health equity at its core, in recognition of the increasing health disparities in our country and the overwhelming evidence of the damaging effect of structural racism on cardiovascular and stroke health. Concurrent with the announcement of the new Impact Goal was the release of an American Heart Association presidential advisory on structural racism, recognizing racism as a fundamental driver of health disparities and directing the American Heart Association to advance antiracist strategies regarding science, business operations, leadership, quality improvement, and advocacy. This policy statement builds on the call to action put forth in our presidential advisory, discussing specific opportunities to leverage public policy in promoting overall well-being and rectifying those long-standing structural barriers that impede the progress that we need and seek for the health of all communities. Although this policy statement discusses difficult aspects of our past, it is meant to provide a forward-looking blueprint that can be embraced by a broad spectrum of stakeholders who share the association's commitment to addressing structural racism and realizing true health equity.


Assuntos
Equidade em Saúde , Racismo , Estados Unidos , Humanos , Racismo Sistêmico , American Heart Association , Pandemias/prevenção & controle , Racismo/prevenção & controle , Política Pública
14.
Circulation ; 149(20): e1176-e1188, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38602110

RESUMO

Patient-centered care is gaining widespread acceptance by the medical and lay communities and is increasingly recognized as a goal of high-quality health care delivery. Patient-centered care is based on ethical principles and aims at establishing a partnership between the health care team and patient, family member, or both in the care planning and decision-making process. Patient-centered care involves providing respectful care by tailoring management decisions to patients' beliefs, preferences, and values. A collaborative care approach can enhance patient engagement, foster shared decision-making that aligns with patient values and goals, promote more personalized and effective cardiovascular care, and potentially improve patient outcomes. The objective of this scientific statement is to inform health care professionals and stakeholders about the role and impact of patient-centered care in adult cardiovascular medicine. This scientific statement describes the background and rationale for patient-centered care in cardiovascular medicine, provides insight into patient-oriented medication management and patient-reported outcome measures, highlights opportunities and strategies to overcome challenges in patient-centered care, and outlines knowledge gaps and future directions.


Assuntos
American Heart Association , Doenças Cardiovasculares , Assistência Centrada no Paciente , Humanos , Assistência Centrada no Paciente/normas , Estados Unidos , Doenças Cardiovasculares/terapia , Adulto , Participação do Paciente , Cardiologia/normas
15.
J Virol ; 98(4): e0013224, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38511932

RESUMO

Heartland virus (HRTV) is an emerging tick-borne bandavirus that causes a febrile illness of varying severity in humans, with cases reported in eastern and midwestern regions of the United States. No vaccines or approved therapies are available to prevent or treat HRTV disease. Here, we describe the genetic changes, natural history of disease, and pathogenesis of a mouse-adapted HRTV (MA-HRTV) that is uniformly lethal in 7- to 8-week-old AG129 mice at low challenge doses. We used this model to assess the efficacy of the ribonucleoside analog, 4'-fluorouridine (EIDD-2749), and showed that once-daily oral treatment with 3 mg/kg of drug, initiated after the onset of disease, protects mice against lethal MA-HRTV challenge and reduces viral loads in blood and tissues. Our findings provide insights into HRTV virulence and pathogenesis and support further development of EIDD-2749 as a therapeutic intervention for HRTV disease. IMPORTANCE: More than 60 cases of HRTV disease spanning 14 states have been reported to the United States Centers for Disease Control and Prevention. The expanding range of the Lone Star tick that transmits HRTV, the growing population of at-risk persons living in geographic areas where the tick is abundant, and the lack of antiviral treatments or vaccines raise significant public health concerns. Here, we report the development of a new small-animal model of lethal HRTV disease to gain insight into HRTV pathogenesis and the application of this model for the preclinical development of a promising new antiviral drug candidate, EIDD-2749. Our findings shed light on how the virus causes disease and support the continued development of EIDD-2749 as a therapeutic for severe cases of HRTV infection.


Assuntos
Infecções por Bunyaviridae , Bunyaviridae , Nucleotídeos de Uracila , Animais , Humanos , Camundongos , Infecções por Bunyaviridae/tratamento farmacológico , Carrapatos , Estados Unidos , Nucleotídeos de Uracila/uso terapêutico
16.
J Virol ; 98(4): e0011224, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38506509

RESUMO

Live-attenuated virus vaccines provide long-lived protection against viral disease but carry inherent risks of residual pathogenicity and genetic reversion. The live-attenuated Candid#1 vaccine was developed to protect Argentines against lethal infection by the Argentine hemorrhagic fever arenavirus, Junín virus. Despite its safety and efficacy in Phase III clinical study, the vaccine is not licensed in the US, in part due to concerns regarding the genetic stability of attenuation. Previous studies had identified a single F427I mutation in the transmembrane domain of the Candid#1 envelope glycoprotein GPC as the key determinant of attenuation, as well as the propensity of this mutation to revert upon passage in cell culture and neonatal mice. To ascertain the consequences of this reversion event, we introduced the I427F mutation into recombinant Candid#1 (I427F rCan) and investigated the effects in two validated small-animal models: in mice expressing the essential virus receptor (human transferrin receptor 1; huTfR1) and in the conventional guinea pig model. We report that I427F rCan displays only modest virulence in huTfR1 mice and appears attenuated in guinea pigs. Reversion at another attenuating locus in Candid#1 GPC (T168A) was also examined, and a similar pattern was observed. By contrast, virus bearing both revertant mutations (A168T+I427F rCan) approached the lethal virulence of the pathogenic Romero strain in huTfR1 mice. Virulence was less extreme in guinea pigs. Our findings suggest that genetic stabilization at both positions is required to minimize the likelihood of reversion to virulence in a second-generation Candid#1 vaccine.IMPORTANCELive-attenuated virus vaccines, such as measles/mumps/rubella and oral poliovirus, provide robust protection against disease but carry with them the risk of genetic reversion to the virulent form. Here, we analyze the genetics of reversion in the live-attenuated Candid#1 vaccine that is used to protect against Argentine hemorrhagic fever, an often-lethal disease caused by the Junín arenavirus. In two validated small-animal models, we find that restoration of virulence in recombinant Candid#1 viruses requires back-mutation at two positions specific to the Candid#1 envelope glycoprotein GPC, at positions 168 and 427. Viruses bearing only a single change showed only modest virulence. We discuss strategies to genetically harden Candid#1 GPC against these two reversion events in order to develop a safer second-generation Candid#1 vaccine virus.


Assuntos
Febre Hemorrágica Americana , Vírus Junin , Vacinas Virais , Animais , Cobaias , Humanos , Camundongos , Glicoproteínas/genética , Febre Hemorrágica Americana/prevenção & controle , Vírus Junin/fisiologia , População da América do Sul , Vacinas Atenuadas/genética , Vacinas Virais/genética , Virulência
17.
J Allergy Clin Immunol ; 153(1): 103-110.e5, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37877904

RESUMO

BACKGROUND: Place-based social determinants of health are associated with pediatric asthma morbidity. However, there is little evidence on how social determinants of health correlate to the disproportionately high rates of asthma morbidity experienced by children <5 years old. OBJECTIVES: This study sought to evaluate census tract associations between the Child Opportunity Index ±COI) and at-risk rates (ARRs) for pediatric asthma-related emergency department (ED) encounters and hospitalizations in Washington, DC. METHODS: This was a cross-sectional study of children <5 years old with physician-diagnosed asthma included in the DC Asthma Registry between January 2018 and December 2019. Census tract COI score (1-100) and its 3 domains (social/economic, health/environmental, and educational) were the exposures (source: www.diversitydatakids.org). ED and hospitalization ARRs (outcomes) were created by dividing counts of ED encounters and hospitalizations by populations with asthma for each census tract and adjusted for population-level demographic (age, sex, insurance), clinical (asthma severity), and community (violent crime and limited English proficiency) covariates. RESULTS: Within a study population of 3806 children with a mean age of 2.4 ± 1.4 years, 2132 (56%) had 5852 ED encounters, and 821 (22%) had 1418 hospitalizations. Greater census tract overall COI, social/economic COI, and educational COI were associated with fewer ED ARRs. There were no associations between the health/environmental COI and ED ARRs or between the COI and hospitalization ARRs. CONCLUSION: Improving community-level social, economic, and educational opportunity within specific census tracts may reduce ED ARRs in this population.


Assuntos
Asma , Criança , Humanos , Lactente , Pré-Escolar , Estudos Transversais , District of Columbia/epidemiologia , Asma/epidemiologia , Hospitalização , Morbidade , Serviço Hospitalar de Emergência , Estudos Retrospectivos
18.
Prog Polym Sci ; 1482024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38476148

RESUMO

Stimuli-responsive nano-assemblies from amphiphilic macromolecules could undergo controlled structural transformations and generate diverse macroscopic phenomenon under stimuli. Due to the controllable responsiveness, they have been applied for broad material and biomedical applications, such as biologics delivery, sensing, imaging, and catalysis. Understanding the mechanisms of the assembly-disassembly processes and structural determinants behind the responsive properties is fundamentally important for designing the next generation of nano-assemblies with programmable responsiveness. In this review, we focus on structural determinants of assemblies from amphiphilic macromolecules and their macromolecular level alterations under stimuli, such as the disruption of hydrophilic-lipophilic balance (HLB), depolymerization, decrosslinking, and changes of molecular packing in assemblies, which eventually lead to a series of macroscopic phenomenon for practical purposes. Applications of stimuli-responsive nano-assemblies in delivery, sensing and imaging were also summarized based on their structural features. We expect this review could provide readers an overview of the structural considerations in the design and applications of nanoassemblies and incentivize more explorations in stimuli-responsive soft matters.

19.
J Biol Chem ; 299(7): 104896, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37290531

RESUMO

Measuring the relative effect that any two sequence positions have on each other may improve protein design or help better interpret coding variants. Current approaches use statistics and machine learning but rarely consider phylogenetic divergences which, as shown by Evolutionary Trace studies, provide insight into the functional impact of sequence perturbations. Here, we reframe covariation analyses in the Evolutionary Trace framework to measure the relative tolerance to perturbation of each residue pair during evolution. This approach (CovET) systematically accounts for phylogenetic divergences: at each divergence event, we penalize covariation patterns that belie evolutionary coupling. We find that while CovET approximates the performance of existing methods to predict individual structural contacts, it performs significantly better at finding structural clusters of coupled residues and ligand binding sites. For example, CovET found more functionally critical residues when we examined the RNA recognition motif and WW domains. It correlates better with large-scale epistasis screen data. In the dopamine D2 receptor, top CovET residue pairs recovered accurately the allosteric activation pathway characterized for Class A G protein-coupled receptors. These data suggest that CovET ranks highest the sequence position pairs that play critical functional roles through epistatic and allosteric interactions in evolutionarily relevant structure-function motifs. CovET complements current methods and may shed light on fundamental molecular mechanisms of protein structure and function.


Assuntos
Evolução Molecular , Alinhamento de Sequência , Sítios de Ligação/genética , Filogenia , Receptores Acoplados a Proteínas G/genética , Alinhamento de Sequência/métodos
20.
Infect Immun ; : e0048223, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597634

RESUMO

Bacterial infections pose a significant global health threat, accounting for an estimated 7.7 million deaths. Hospital outbreaks driven by multi-drug-resistant pathogens, notably Klebsiella pneumoniae (K. pneumoniae), are of grave concern. This opportunistic pathogen causes pneumonia, urinary tract infections, and bacteremia, particularly in immunocompromised individuals. The rise of hypervirulent K. pneumoniae adds complexity, as it increasingly infects healthy individuals. Recent epidemiological data suggest that asymptomatic gastrointestinal carriage serves as a reservoir for infections in the same individual and allows for host-to-host transmission via the fecal-oral route. This review focuses on K. pneumoniae's gastrointestinal colonization, delving into epidemiological evidence, current animal models, molecular colonization mechanisms, and the protective role of the resident gut microbiota. Moreover, the review sheds light on in vivo high-throughput approaches that have been crucial for identifying K. pneumoniae factors in gut colonization. This comprehensive exploration aims to enhance our understanding of K. pneumoniae gut pathogenesis, guiding future intervention and prevention strategies.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA