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1.
Nat Immunol ; 20(1): 64-72, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30455460

RESUMO

Toxoplasma gondii is a common protozoan parasite that infects up to one third of the world's population. Notably, very little is known about innate immune sensing mechanisms for this obligate intracellular parasite by human cells. Here, by applying an unbiased biochemical screening approach, we show that human monocytes recognized the presence of T. gondii infection by detecting the alarmin S100A11 protein, which is released from parasite-infected cells via caspase-1-dependent mechanisms. S100A11 induced a potent chemokine response to T. gondii by engaging its receptor RAGE, and regulated monocyte recruitment in vivo by inducing expression of the chemokine CCL2. Our experiments reveal a sensing system for T. gondii by human cells that is based on the detection of infection-mediated release of S100A11 and RAGE-dependent induction of CCL2, a crucial chemokine required for host resistance to the parasite.


Assuntos
Quimiocina CCL2/metabolismo , Imunidade Inata , Proteínas S100/metabolismo , Toxoplasma/fisiologia , Toxoplasmose/imunologia , Animais , Antígenos de Neoplasias/metabolismo , Caspase 1/metabolismo , Quimiotaxia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Quinases Ativadas por Mitógeno/metabolismo , RNA Interferente Pequeno/genética , Proteínas S100/genética , Células THP-1
2.
Nat Immunol ; 20(2): 141-151, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30643265

RESUMO

Rheumatoid arthritis is characterized by progressive joint inflammation and affects ~1% of the human population. We noted single-nucleotide polymorphisms (SNPs) in the apoptotic cell-engulfment genes ELMO1, DOCK2, and RAC1 linked to rheumatoid arthritis. As ELMO1 promotes cytoskeletal reorganization during engulfment, we hypothesized that ELMO1 loss would worsen inflammatory arthritis. Surprisingly, Elmo1-deficient mice showed reduced joint inflammation in acute and chronic arthritis models. Genetic and cell-biology studies revealed that ELMO1 associates with receptors linked to neutrophil function in arthritis and regulates activation and early neutrophil recruitment to the joints, without general inhibition of inflammatory responses. Further, neutrophils from the peripheral blood of human donors that carry the SNP in ELMO1 associated with arthritis display increased migratory capacity, whereas ELMO1 knockdown reduces human neutrophil migration to chemokines linked to arthritis. These data identify 'noncanonical' roles for ELMO1 as an important cytoplasmic regulator of specific neutrophil receptors and promoter of arthritis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/imunologia , Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Neutrófilos/imunologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apoptose/imunologia , Artrite Experimental/diagnóstico , Artrite Experimental/genética , Artrite Experimental/patologia , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/genética , Artrite Reumatoide/patologia , Quimiotaxia/genética , Quimiotaxia/imunologia , Colágeno/imunologia , Complemento C5a/imunologia , Complemento C5a/metabolismo , Citoplasma/imunologia , Citoplasma/metabolismo , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Voluntários Saudáveis , Humanos , Microscopia Intravital , Articulações/citologia , Articulações/imunologia , Leucotrieno B4/imunologia , Leucotrieno B4/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/metabolismo , Polimorfismo de Nucleotídeo Único , Proteômica , Índice de Gravidade de Doença , Transdução de Sinais/imunologia , Imagem com Lapso de Tempo
3.
Nat Immunol ; 20(5): 613-625, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30778243

RESUMO

Influenza A, B and C viruses (IAV, IBV and ICV, respectively) circulate globally and infect humans, with IAV and IBV causing the most severe disease. CD8+ T cells confer cross-protection against IAV strains, however the responses of CD8+ T cells to IBV and ICV are understudied. We investigated the breadth of CD8+ T cell cross-recognition and provide evidence of CD8+ T cell cross-reactivity across IAV, IBV and ICV. We identified immunodominant CD8+ T cell epitopes from IBVs that were protective in mice and found memory CD8+ T cells directed against universal and influenza-virus-type-specific epitopes in the blood and lungs of healthy humans. Lung-derived CD8+ T cells displayed tissue-resident memory phenotypes. Notably, CD38+Ki67+CD8+ effector T cells directed against novel epitopes were readily detected in IAV- or IBV-infected pediatric and adult subjects. Our study introduces a new paradigm whereby CD8+ T cells confer unprecedented cross-reactivity across all influenza viruses, a key finding for the design of universal vaccines.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Reações Cruzadas/imunologia , Gammainfluenzavirus/imunologia , Vírus da Influenza A/imunologia , Vírus da Influenza B/imunologia , Influenza Humana/imunologia , Adolescente , Adulto , Idoso , Animais , Linfócitos T CD8-Positivos/virologia , Criança , Epitopos de Linfócito T/imunologia , Feminino , Humanos , Vírus da Influenza A/fisiologia , Vírus da Influenza B/fisiologia , Vacinas contra Influenza/imunologia , Influenza Humana/virologia , Gammainfluenzavirus/fisiologia , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem
4.
Immunity ; 54(8): 1715-1727.e7, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34283971

RESUMO

Allergic airway inflammation is driven by type-2 CD4+ T cell inflammatory responses. We uncover an immunoregulatory role for the nucleotide release channel, Panx1, in T cell crosstalk during airway disease. Inverse correlations between Panx1 and asthmatics and our mouse models revealed the necessity, specificity, and sufficiency of Panx1 in T cells to restrict inflammation. Global Panx1-/- mice experienced exacerbated airway inflammation, and T-cell-specific deletion phenocopied Panx1-/- mice. A transgenic designed to re-express Panx1 in T cells reversed disease severity in global Panx1-/- mice. Panx1 activation occurred in pro-inflammatory T effector (Teff) and inhibitory T regulatory (Treg) cells and mediated the extracellular-nucleotide-based Treg-Teff crosstalk required for suppression of Teff cell proliferation. Mechanistic studies identified a Salt-inducible kinase-dependent phosphorylation of Panx1 serine 205 important for channel activation. A genetically targeted mouse expressing non-phosphorylatable Panx1S205A phenocopied the exacerbated inflammation in Panx1-/- mice. These data identify Panx1-dependent Treg:Teff cell communication in restricting airway disease.


Assuntos
Asma/imunologia , Comunicação Celular/imunologia , Conexinas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Linfócitos T Reguladores/imunologia , Animais , Linhagem Celular , Proliferação de Células/fisiologia , Conexinas/genética , Modelos Animais de Doenças , Células HEK293 , Humanos , Células Jurkat , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Sistema Respiratório/imunologia
5.
Immunity ; 47(6): 1142-1153.e4, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29262350

RESUMO

Memory B cells (MBCs) and plasma cells (PCs) constitute the two cellular outputs of germinal center (GC) responses that together facilitate long-term humoral immunity. Although expression of the transcription factor BLIMP-1 identifies cells undergoing PC differentiation, no such marker exists for cells committed to the MBC lineage. Here, we report that the chemokine receptor CCR6 uniquely marks MBC precursors in both mouse and human GCs. CCR6+ GC B cells were highly enriched within the GC light zone (LZ), were the most quiescent of all GC B cells, exhibited a cell-surface phenotype and gene expression signature indicative of an MBC transition, and possessed the augmented response characteristics of MBCs. MBC precursors within the GC LZ predominantly possessed a low affinity for antigen but also included cells from within the high-affinity pool. These data indicate a fundamental dichotomy between the processes that drive MBC and PC differentiation during GC responses.


Assuntos
Centro Germinativo/imunologia , Imunidade Humoral , Plasmócitos/imunologia , Células Precursoras de Linfócitos B/imunologia , Receptores CCR6/imunologia , Animais , Antígeno B7-2/genética , Antígeno B7-2/imunologia , Diferenciação Celular , Linhagem da Célula/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Centro Germinativo/citologia , Humanos , Memória Imunológica , Imunofenotipagem , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Plasmócitos/citologia , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Fator 1 de Ligação ao Domínio I Regulador Positivo/imunologia , Células Precursoras de Linfócitos B/citologia , Receptores CCR6/genética , Receptores CXCR4/genética , Receptores CXCR4/imunologia , Transdução de Sinais
6.
BMC Cancer ; 24(1): 442, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600473

RESUMO

Head and neck cancers, particularly oropharyngeal cancers (OPC), have been increasingly associated with human papillomavirus (HPV) infections, specifically HPV16. The current methods for HPV16 detection primarily rely on p16 staining or PCR techniques. However, it is important to note the limitations of conventional PCR, as the presence of viral DNA does not always indicate an ongoing viral infection. Moreover, these tests heavily rely on the availability of tissue samples, which can present challenges in certain situations. In this study, we developed a RT-qPCR biplex approach to detect HPV16 oncogenes E6 and E7 RNA in saliva samples from OPC patients. Salivary supernatant was used as the liquid biopsy source. We successfully obtained RNA from salivary supernatant, preserving its integrity as indicated by the detection of several housekeeping genes. Our biplex approach accurately detected E6 and E7 RNA in HPV16-positive cell lines, tissues, and finally in OPC salivary samples. Importantly, the assay specifically targeted HPV16 and not HPV18. This biplexing technique allowed for reduced sample input without compromising specificity. In summary, our approach demonstrates the potential to detect viable HPV16 in saliva from OPC patients. Since the assay measures HPV16 RNA, it provides insights into the transcriptional activity of the virus. This could guide clinical decision-making and treatment planning for individuals with HPV-related OPC.


Assuntos
Proteínas Oncogênicas Virais , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Humanos , Papillomavirus Humano 16/genética , Saliva/metabolismo , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/complicações , Proteínas Oncogênicas Virais/genética , Neoplasias Orofaríngeas/patologia , RNA , Reação em Cadeia da Polimerase , Proteínas E7 de Papillomavirus/genética
7.
Exp Eye Res ; : 110101, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39303842

RESUMO

Endothelial cells (ECs) display organ- and tissue-specific heterogeneity. In the eye, the retinal and choroidal vascular beds are distinct networks with different molecular and morphological properties that serve location-specific functions, i.e., the former maintaining a tight barrier and the latter, a permeable fenestrated vasculature. Given that retinal health critically relies on the function of these vascular beds and that their dysfunction is implicated in a variety of retinal diseases, a molecular understanding of both physiological and pathophysiological characteristics of these distinct vasculatures is critical. Given their interspersed anatomic distribution among parenchymal cells, the study of EC gene expression, in vivo, has been hampered by the challenge of isolating pure populations of ocular ECs in sufficient quantities for large-scale transcriptomics. To address this challenge, we present a methodological and analytical workflow to facilitate inter-tissue comparisons of the in vivo EC translatome isolated from choroid, retina, and brain using the Cre-inducible NuTRAP flox construct and two widely-used endothelial Cre mouse lines: constitutive Tie2-Cre and tamoxifen-inducible Cdh5-CreERT2. For each Cre line, inter-tissue comparison of TRAP-RNAseq enrichment (TRAP-isolated translatome vs input transcriptome) showed tissue-specific gene enrichments with differential pathway representation. For each mouse model, inter-tissue comparison of the EC translatome (choroid vs brain, choroid vs retina, and brain vs retina) showed over 50% overlap of differentially expressed genes (DEGs) between the three paired comparisons, with differential pathway representation for each tissue. Pathway analysis of DEGs in the Cdh5-NuTRAP vs Tie2-NuTRAP comparison for retina, choroid, and brain predicted inhibition of processes related to myeloid cell function and activation, consistent with more specific targeting of ECs in the Cdh5-NuTRAP than in the Tie2-NuTRAP model which also targets hematopoietic progenitors giving rise to immune cells. Indeed, while TRAP enriches for EC transcripts in both models, myeloid transcripts were also captured in the Tie2-NuTRAP model which was confirmed using cell sorting. We suggest experimental/analytical considerations should be taken when selecting Cre-lines to target ECs.

8.
Biometrics ; 80(1)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38386360

RESUMO

A major challenge in longitudinal built-environment health studies is the accuracy of commercial business databases that are used to characterize dynamic food environments. Different databases often provide conflicting exposure measures on the same subject due to different source credibilities. As on-site verification is not feasible for historical data, we suggest combining multiple databases to correct the bias in health effect estimates due to measurement error in any 1 datasource. We propose a joint model for the time-varying health outcomes, observed count exposures, and latent true count exposures. Our model estimates the time-specific quality of sources and incorporates time dependence of true count exposure by Poisson integer-valued first-order autoregressive process. We take a Bayesian nonparametric approach to flexibly account for location-specific exposures. By resolving the discordance between different databases, our method reduces the bias in the longitudinal health effect of the true exposures. Our method is demonstrated with childhood obesity data in California public schools with respect to convenience store exposures in school neighborhoods from 2001 to 2008.


Assuntos
Obesidade Infantil , Criança , Humanos , Teorema de Bayes , Bases de Dados Factuais , Instituições Acadêmicas
9.
Psychooncology ; 33(9): e9311, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39285611

RESUMO

OBJECTIVE: Understanding survivorship issues among people with head and neck cancer (HNC) is important as survival rates increase. Most research has focused on urban patients, leaving a gap in understanding the challenges faced by those in rural areas. This study aims to summarise the literature on survivorship needs for people with HNC in rural areas. METHODS: PubMed, PsycINFO, Scopus, Medline, CINAHL, Web of Science, and Embase were searched from database inception to 10 July 2024, with no restriction on publication period, country, or language. Data on study aims, country, methodology, and major findings related to HNC survivors in rural areas were extracted. Study quality was assessed using the Joanna Briggs Institute critical appraisal checklists. RESULTS: Twenty-one studies met the inclusion criteria. Eight studies were qualitative, 11 were quantitative, and two adopted a mixed-methods approach. Results demonstrate the impact of complex treatments on physical (n = 13) and psychosocial (n = 14) functioning. This study also emphasises multifaceted challenges, including reduced access to specialised services, resulting in greater travel and financial burden, extending to caregivers. Hence, primary healthcare services are crucial in supporting these patients closer to home. CONCLUSIONS: Addressing the gaps in equitable post-treatment care requires an even distribution of healthcare funding and workforce in rural areas. Future research could target these issues to develop tailored interventions or models of care, such as shared care, to ease access and financial burden.


Assuntos
Sobreviventes de Câncer , Neoplasias de Cabeça e Pescoço , População Rural , Sobrevivência , Humanos , Neoplasias de Cabeça e Pescoço/psicologia , Neoplasias de Cabeça e Pescoço/terapia , Neoplasias de Cabeça e Pescoço/mortalidade , População Rural/estatística & dados numéricos , Sobreviventes de Câncer/psicologia , Sobreviventes de Câncer/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Avaliação das Necessidades
10.
Prev Med ; 179: 107850, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199591

RESUMO

OBJECTIVE: To examine associations of concern, worry, and stress about discrimination, shootings/violence, and police brutality and exclusive and dual tobacco and cannabis use among young adults. METHODS: A prospective, racially/ethnically diverse cohort of young adults (n = 1960) living in Los Angeles, California completed a baseline survey in 2020 (age range: 19-23) and a follow-up survey in 2021. Exploratory factor analysis (EFA) was employed on nine variables assessing levels of concern, worry, and stress about societal discrimination, societal shootings/violence, and community police brutality at baseline. Past 30-day tobacco and cannabis use at follow-up was categorized as current exclusive tobacco, exclusive cannabis, and dual tobacco and cannabis (vs never/former) use based on eleven use variables. Multinomial logistic regressions estimated adjusted associations between each factor score (translated to standard deviation units) with exclusive and dual tobacco and cannabis use. RESULTS: The EFA produced four factor scores representing concern/worry/stress (i.e., distress) about community police brutality (F1), distress about societal shootings/violence (F2), and distress about societal discrimination (F3), as well as generalized stress about police brutality, shootings/violence, and discrimination (F4). F1, F2, and F3 were associated with subsequent exclusive current cannabis use, with F1 having the strongest association (OR: 1.35, 95% CI: 1.18-1.55), while only F1 (OR: 1.51, 95% CI: 1.27-1.78) was associated with dual tobacco and cannabis use. None of the factors were associated with exclusive tobacco use. CONCLUSIONS: Young adult concern, worry, and/or stress about social problems may increase risk of cannabis use with or without concurrent tobacco use 6-12 months later.


Assuntos
Cannabis , Sistemas Eletrônicos de Liberação de Nicotina , Uso da Maconha , Produtos do Tabaco , Humanos , Adulto Jovem , Adulto , Estudos Prospectivos , Los Angeles/epidemiologia , Uso da Maconha/epidemiologia , Uso de Tabaco/epidemiologia , Violência
11.
J Cardiovasc Magn Reson ; 26(2): 101055, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38971501

RESUMO

BACKGROUND: Cardiovascular magnetic resonance (CMR) is increasingly utilized to evaluate expanding cardiovascular conditions. The Society for Cardiovascular Magnetic Resonance (SCMR) Registry is a central repository for real-world clinical data to support cardiovascular research, including those relating to outcomes, quality improvement, and machine learning. The SCMR Registry is built on a regulatory-compliant, cloud-based infrastructure that houses searchable content and Digital Imaging and Communications in Medicine images. The goal of this study is to summarize the status of the SCMR Registry at 150,000 exams. METHODS: The processes for data security, data submission, and research access are outlined. We interrogated the Registry and presented a summary of its contents. RESULTS: Data were compiled from 154,458 CMR scans across 20 United States sites, containing 299,622,066 total images (∼100 terabytes of storage). Across reported values, the human subjects had an average age of 58 years (range 1 month to >90 years old), were 44% (63,070/145,275) female, 72% (69,766/98,008) Caucasian, and had a mortality rate of 8% (9,962/132,979). The most common indication was cardiomyopathy (35,369/131,581, 27%), and most frequently used current procedural terminology code was 75561 (57,195/162,901, 35%). Macrocyclic gadolinium-based contrast agents represented 89% (83,089/93,884) of contrast utilization after 2015. Short-axis cines were performed in 99% (76,859/77,871) of tagged scans, short-axis late gadolinium enhancement (LGE) in 66% (51,591/77,871), and stress perfusion sequences in 30% (23,241/77,871). Mortality data demonstrated increased mortality in patients with left ventricular ejection fraction <35%, the presence of wall motion abnormalities, stress perfusion defects, and infarct LGE, compared to those without these markers. There were 456,678 patient-years of all-cause mortality follow-up, with a median follow-up time of 3.6 years. CONCLUSION: The vision of the SCMR Registry is to promote evidence-based utilization of CMR through a collaborative effort by providing a web mechanism for centers to securely upload de-identified data and images for research, education, and quality control. The Registry quantifies changing practice over time and supports large-scale real-world multicenter observational studies of prognostic utility.

12.
AIDS Behav ; 28(3): 811-819, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37792230

RESUMO

People with HIV (PWH) are susceptible to neurocognitive, physical, and mental health problems that may decrease their likelihood of experiencing successful aging. This cross-sectional, retrospective study estimated the extent to which health literacy is associated with successful aging among 116 older PWH and 60 persons without HIV. Successful aging was defined using indicators of biological health, cognitive efficiency, mental health, and productivity. Health literacy was measured using the Rapid Estimate of Adult Literacy in Medicine, Newest Vital Sign, Brief Health Literacy Screening, and Beliefs Related to Medication Adherence. A series of logistic regressions covarying for education showed that better health literacy was associated with a higher frequency of successful aging among older PWH. Older PWH were approximately three times less likely to experience successful aging as compared to older adults without HIV. Future studies may examine whether improving health literacy among younger PWH increases the likelihood of successful aging.


Assuntos
Infecções por HIV , Letramento em Saúde , Humanos , Idoso , Estudos Transversais , Estudos Retrospectivos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/complicações , Envelhecimento
13.
Nicotine Tob Res ; 26(8): 1089-1096, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38127643

RESUMO

INTRODUCTION: Achieving cessation in people with established smoking patterns remains a challenge. Increasing cigarette prices has been one of the most successful strategies for lowering smoking rates. The extent to which it has remained effective in encouraging cessation among adults in recent years and how the effectiveness has varied by sociodemographic characteristics is unclear. AIMS AND METHODS: Using repeated cross-sectional data collected by the Tobacco Use Supplement of the Current Population Survey, we investigate the relationship between cigarette prices and cessation from 2003 to 2019 in adults at least 25 years old. We examine the associations between price and cessation in the population overall and by sex, race and ethnicity, and socioeconomic status. RESULTS: We found mixed support for associations between greater local prices and cessation. Unadjusted models showed that greater local prices were associated with greater odds of cessation, but the associations did not persist after controlling for sociodemographic characteristics. The associations did not significantly differ by respondent characteristics. Sensitivity analysis using alternative specifications and retail state price as the main predictor showed similar results. Sensitivity analysis with controls for e-cigarette use in the 2014-2019 period showed that greater local price was associated with cessation among adults with less than a high school degree. When stratified by year of data collection, results show that greater local prices were associated with cessation after 2009. CONCLUSIONS: Overall, the study adds to the conflicting evidence on the effectiveness of increasing prices on smoking cessation among adults with established smoking patterns. IMPLICATIONS: Higher cigarette prices have been one of the most successful tools for lowering smoking prevalence. It remains unclear how effective they have been in recent years in encouraging adults with established smoking patterns to quit. The study's results show that greater local prices were associated with higher odds of cessation, but the association did not persist after sociodemographic adjustment. In a sensitivity analysis, greater local price was associated with cessation among people with less than a high school degree in models controlling for e-cigarette use. We also found evidence that greater local price was associated with cessation after 2009. More comprehensive smoke-free coverage was also associated with greater odds of cessation. The study's results highlight that encouraging cessation among adults with an established smoking pattern remains a challenging policy problem even when cigarette prices rise.


Assuntos
Comércio , Abandono do Hábito de Fumar , Produtos do Tabaco , Humanos , Abandono do Hábito de Fumar/economia , Abandono do Hábito de Fumar/estatística & dados numéricos , Estados Unidos/epidemiologia , Masculino , Feminino , Adulto , Produtos do Tabaco/economia , Estudos Transversais , Pessoa de Meia-Idade , Comércio/estatística & dados numéricos , Comércio/economia
14.
BMC Public Health ; 24(1): 2655, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39342237

RESUMO

BACKGROUND: A major challenge in epidemiology is knowing when an exposure effect is large enough to be clinically important, in particular how to interpret a difference in mean outcome in unexposed/exposed groups. Where it can be calculated, the proportion/percentage beyond a suitable cut-point is useful in defining individuals at high risk to give a more meaningful outcome. In this simulation study we compute differences in outcome means and proportions that arise from hypothetical small effects in vulnerable sub-populations. METHODS: Data from over 28,000 mother/child pairs belonging to the Environmental influences on Child Health Outcomes Program were used to examine the impact of hypothetical environmental exposures on mean birthweight, and low birthweight (LBW) (birthweight < 2500g). We computed mean birthweight in unexposed/exposed groups by sociodemographic categories (maternal education, health insurance, race, ethnicity) using a range of hypothetical exposure effect sizes. We compared the difference in mean birthweight and the percentage LBW, calculated using a distributional approach. RESULTS: When the hypothetical mean exposure effect was fixed (at 50, 125, 167 or 250g), the absolute difference in % LBW (risk difference) was not constant but varied by socioeconomic categories. The risk differences were greater in sub-populations with the highest baseline percentages LBW: ranging from 3.1-5.3 percentage points for exposure effect of 125g. Similar patterns were seen for other mean exposure sizes simulated. CONCLUSIONS: Vulnerable sub-populations with greater baseline percentages at high risk fare worse when exposed to a small insult compared to the general population. This illustrates another facet of health disparity in vulnerable individuals.


Assuntos
Peso ao Nascer , Saúde da Criança , Recém-Nascido de Baixo Peso , Populações Vulneráveis , Humanos , Populações Vulneráveis/estatística & dados numéricos , Feminino , Recém-Nascido , Saúde da Criança/estatística & dados numéricos , Exposição Ambiental/efeitos adversos , Estudos de Coortes , Gravidez , Fatores Socioeconômicos , Masculino , Adulto
15.
Biom J ; 66(1): e2200324, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37776057

RESUMO

A common practice in clinical trials is to evaluate a treatment effect on an intermediate outcome when the true outcome of interest would be difficult or costly to measure. We consider how to validate intermediate outcomes in a causally-valid way when the trial outcomes are time-to-event. Using counterfactual outcomes, those that would be observed if the counterfactual treatment had been given, the causal association paradigm assesses the relationship of the treatment effect on the surrogate outcome with the treatment effect on the true, primary outcome. In particular, we propose illness-death models to accommodate the censored and semicompeting risk structure of survival data. The proposed causal version of these models involves estimable and counterfactual frailty terms. Via these multistate models, we characterize what a valid surrogate would look like using a causal effect predictiveness plot. We evaluate the estimation properties of a Bayesian method using Markov chain Monte Carlo and assess the sensitivity of our model assumptions. Our motivating data source is a localized prostate cancer clinical trial where the two survival outcomes are time to distant metastasis and time to death.


Assuntos
Fragilidade , Modelos Estatísticos , Humanos , Teorema de Bayes , Biomarcadores
16.
Alzheimers Dement ; 20(8): 5338-5346, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38934219

RESUMO

INTRODUCTION: Neighborhood socioeconomic status (SES) has been linked to dementia, but the distribution of SES within a neighborhood may also matter. METHODS: Data from 460 (47% Black, 46% White) older adults from the Michigan Cognitive Aging Project were linked to census tract-level data from the National Neighborhood Data Archive (NaNDA). Neighborhood SES included two composites reflecting disadvantage and affluence. Neighborhood racial income inequality was the ratio of median incomes for White versus Black residents. Generalized estimating equations examined associations between neighborhood factors and cognitive domains. RESULTS: Neighborhood racial income inequality was uniquely associated with worse cognitive health, and these associations did not differ by participant race. Neighborhood disadvantage was only associated with worse cognitive health among Black participants. DISCUSSION: Both the level and racial distribution of SES within a neighborhood may be relevant for dementia risk. Racial differences in the level and impact of neighborhood SES contribute to dementia inequalities. HIGHLIGHTS: Black participants lived in neighborhoods with lower socioeconomic status (SES) than White participants, on average. Neighborhood SES and racial income inequality were associated with worse cognition. Effects of neighborhood racial income inequality did not differ across racial groups. Effects of neighborhood SES were only evident among Black participants.


Assuntos
Renda , Características da Vizinhança , Classe Social , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Negro ou Afro-Americano , Cognição , Demência/epidemiologia , Demência/etnologia , Renda/estatística & dados numéricos , Michigan/epidemiologia , Características da Vizinhança/estatística & dados numéricos , Fatores Socioeconômicos , Brancos
17.
J Environ Manage ; 350: 119644, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38000275

RESUMO

Switching from fossil fuels to renewable energy is key to international energy transition efforts and the move toward net zero. For many nations, this requires decommissioning of hundreds of oil and gas infrastructure in the marine environment. Current international, regional and national legislation largely dictates that structures must be completely removed at end-of-life although, increasingly, alternative decommissioning options are being promoted and implemented. Yet, a paucity of real-world case studies describing the impacts of decommissioning on the environment make decision-making with respect to which option(s) might be optimal for meeting international and regional strategic environmental targets challenging. To address this gap, we draw together international expertise and judgment from marine environmental scientists on marine artificial structures as an alternative source of evidence that explores how different decommissioning options might ameliorate pressures that drive environmental status toward (or away) from environmental objectives. Synthesis reveals that for 37 United Nations and Oslo-Paris Commissions (OSPAR) global and regional environmental targets, experts consider repurposing or abandoning individual structures, or abandoning multiple structures across a region, as the options that would most strongly contribute toward targets. This collective view suggests complete removal may not be best for the environment or society. However, different decommissioning options act in different ways and make variable contributions toward environmental targets, such that policy makers and managers would likely need to prioritise some targets over others considering political, social, economic, and ecological contexts. Current policy may not result in optimal outcomes for the environment or society.


Assuntos
Monitoramento Ambiental , Campos de Petróleo e Gás , Energia Renovável , Combustíveis Fósseis
18.
J Environ Manage ; 352: 119897, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38184869

RESUMO

Thousands of artificial ('human-made') structures are present in the marine environment, many at or approaching end-of-life and requiring urgent decisions regarding their decommissioning. No consensus has been reached on which decommissioning option(s) result in optimal environmental and societal outcomes, in part, owing to a paucity of evidence from real-world decommissioning case studies. To address this significant challenge, we asked a worldwide panel of scientists to provide their expert opinion. They were asked to identify and characterise the ecosystem effects of artificial structures in the sea, their causes and consequences, and to identify which, if any, should be retained following decommissioning. Experts considered that most of the pressures driving ecological and societal effects from marine artificial structures (MAS) were of medium severity, occur frequently, and are dependent on spatial scale with local-scale effects of greater magnitude than regional effects. The duration of many effects following decommissioning were considered to be relatively short, in the order of days. Overall, environmental effects of structures were considered marginally undesirable, while societal effects marginally desirable. Experts therefore indicated that any decision to leave MAS in place at end-of-life to be more beneficial to society than the natural environment. However, some individual environmental effects were considered desirable and worthy of retention, especially in certain geographic locations, where structures can support improved trophic linkages, increases in tourism, habitat provision, and population size, and provide stability in population dynamics. The expert analysis consensus that the effects of MAS are both negative and positive for the environment and society, gives no strong support for policy change whether removal or retention is favoured until further empirical evidence is available to justify change to the status quo. The combination of desirable and undesirable effects associated with MAS present a significant challenge for policy- and decision-makers in their justification to implement decommissioning options. Decisions may need to be decided on a case-by-case basis accounting for the trade-off in costs and benefits at a local level.


Assuntos
Ecossistema , Campos de Petróleo e Gás , Humanos , Consenso , Meio Ambiente , Clima
19.
N Engl J Med ; 383(10): 919-930, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32877582

RESUMO

BACKGROUND: Sodium phenylbutyrate and taurursodiol have been found to reduce neuronal death in experimental models. The efficacy and safety of a combination of the two compounds in persons with amyotrophic lateral sclerosis (ALS) are not known. METHODS: In this multicenter, randomized, double-blind trial, we enrolled participants with definite ALS who had had an onset of symptoms within the previous 18 months. Participants were randomly assigned in a 2:1 ratio to receive sodium phenylbutyrate-taurursodiol (3 g of sodium phenylbutyrate and 1 g of taurursodiol, administered once a day for 3 weeks and then twice a day) or placebo. The primary outcome was the rate of decline in the total score on the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R; range, 0 to 48, with higher scores indicating better function) through 24 weeks. Secondary outcomes were the rates of decline in isometric muscle strength, plasma phosphorylated axonal neurofilament H subunit levels, and the slow vital capacity; the time to death, tracheostomy, or permanent ventilation; and the time to death, tracheostomy, permanent ventilation, or hospitalization. RESULTS: A total of 177 persons with ALS were screened for eligibility, and 137 were randomly assigned to receive sodium phenylbutyrate-taurursodiol (89 participants) or placebo (48 participants). In a modified intention-to-treat analysis, the mean rate of change in the ALSFRS-R score was -1.24 points per month with the active drug and -1.66 points per month with placebo (difference, 0.42 points per month; 95% confidence interval, 0.03 to 0.81; P = 0.03). Secondary outcomes did not differ significantly between the two groups. Adverse events with the active drug were mainly gastrointestinal. CONCLUSIONS: Sodium phenylbutyrate-taurursodiol resulted in slower functional decline than placebo as measured by the ALSFRS-R score over a period of 24 weeks. Secondary outcomes were not significantly different between the two groups. Longer and larger trials are necessary to evaluate the efficacy and safety of sodium phenylbutyrate-taurursodiol in persons with ALS. (Funded by Amylyx Pharmaceuticals and others; CENTAUR ClinicalTrials.gov number, NCT03127514.).


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Fenilbutiratos/uso terapêutico , Ácido Tauroquenodesoxicólico/uso terapêutico , Idoso , Progressão da Doença , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Fenilbutiratos/efeitos adversos , Índice de Gravidade de Doença , Ácido Tauroquenodesoxicólico/administração & dosagem , Resultado do Tratamento
20.
Biometrics ; 79(3): 1840-1852, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35833874

RESUMO

Valid surrogate endpoints S can be used as a substitute for a true outcome of interest T to measure treatment efficacy in a clinical trial. We propose a causal inference approach to validate a surrogate by incorporating longitudinal measurements of the true outcomes using a mixed modeling approach, and we define models and quantities for validation that may vary across the study period using principal surrogacy criteria. We consider a surrogate-dependent treatment efficacy curve that allows us to validate the surrogate at different time points. We extend these methods to accommodate a delayed-start treatment design where all patients eventually receive the treatment. Not all parameters are identified in the general setting. We apply a Bayesian approach for estimation and inference, utilizing more informative prior distributions for selected parameters. We consider the sensitivity of these prior assumptions as well as assumptions of independence among certain counterfactual quantities conditional on pretreatment covariates to improve identifiability. We examine the frequentist properties (bias of point and variance estimates, credible interval coverage) of a Bayesian imputation method. Our work is motivated by a clinical trial of a gene therapy where the functional outcomes are measured repeatedly throughout the trial.


Assuntos
Modelos Estatísticos , Humanos , Teorema de Bayes , Biomarcadores , Resultado do Tratamento , Causalidade
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