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1.
Nat Immunol ; 20(1): 64-72, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30455460

RESUMEN

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.


Asunto(s)
Quimiocina CCL2/metabolismo , Inmunidad Innata , Proteínas S100/metabolismo , Toxoplasma/fisiología , Toxoplasmosis/inmunología , Animales , Antígenos de Neoplasias/metabolismo , Caspasa 1/metabolismo , Quimiotaxis , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Quinasas Activadas por Mitógenos/metabolismo , ARN Interferente Pequeño/genética , Proteínas S100/genética , Células THP-1
2.
Nat Immunol ; 20(2): 141-151, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30643265

RESUMEN

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.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/inmunología , Artritis Experimental/inmunología , Artritis Reumatoide/inmunología , Neutrófilos/inmunología , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Apoptosis/inmunología , Artritis Experimental/diagnóstico , Artritis Experimental/genética , Artritis Experimental/patología , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/genética , Artritis Reumatoide/patología , Quimiotaxis/genética , Quimiotaxis/inmunología , Colágeno/inmunología , Complemento C5a/inmunología , Complemento C5a/metabolismo , Citoplasma/inmunología , Citoplasma/metabolismo , Modelos Animales de Enfermedad , Femenino , Perfilación de la Expresión Génica , Voluntarios Sanos , Humanos , Microscopía Intravital , Articulaciones/citología , Articulaciones/inmunología , Leucotrieno B4/inmunología , Leucotrieno B4/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neutrófilos/metabolismo , Polimorfismo de Nucleótido Simple , Proteómica , Índice de Severidad de la Enfermedad , Transducción de Señal/inmunología , Imagen de Lapso de Tiempo
3.
Nat Immunol ; 20(5): 613-625, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30778243

RESUMEN

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.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Reacciones Cruzadas/inmunología , Gammainfluenzavirus/inmunología , Virus de la Influenza A/inmunología , Virus de la Influenza B/inmunología , Gripe Humana/inmunología , Adolescente , Adulto , Anciano , Animales , Linfocitos T CD8-positivos/virología , Niño , Epítopos de Linfocito T/inmunología , Femenino , Humanos , Virus de la Influenza A/fisiología , Virus de la Influenza B/fisiología , Vacunas contra la Influenza/inmunología , Gripe Humana/virología , Gammainfluenzavirus/fisiología , Masculino , Ratones , Persona de Mediana Edad , Adulto Joven
4.
Immunity ; 54(8): 1715-1727.e7, 2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34283971

RESUMEN

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.


Asunto(s)
Asma/inmunología , Comunicación Celular/inmunología , Conexinas/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Linfocitos T Reguladores/inmunología , Animales , Línea Celular , Proliferación Celular/fisiología , Conexinas/genética , Modelos Animales de Enfermedad , Células HEK293 , Humanos , Células Jurkat , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas del Tejido Nervioso/genética , Sistema Respiratorio/inmunología
5.
Immunity ; 47(6): 1142-1153.e4, 2017 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-29262350

RESUMEN

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.


Asunto(s)
Centro Germinal/inmunología , Inmunidad Humoral , Células Plasmáticas/inmunología , Células Precursoras de Linfocitos B/inmunología , Receptores CCR6/inmunología , Animales , Antígeno B7-2/genética , Antígeno B7-2/inmunología , Diferenciación Celular , Linaje de la Célula/inmunología , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Centro Germinal/citología , Humanos , Memoria Inmunológica , Inmunofenotipificación , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fenotipo , Células Plasmáticas/citología , Factor 1 de Unión al Dominio 1 de Regulación Positiva/genética , Factor 1 de Unión al Dominio 1 de Regulación Positiva/inmunología , Células Precursoras de Linfocitos B/citología , Receptores CCR6/genética , Receptores CXCR4/genética , Receptores CXCR4/inmunología , Transducción de Señal
6.
BMC Cancer ; 24(1): 442, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600473

RESUMEN

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.


Asunto(s)
Proteínas Oncogénicas Virales , Neoplasias Orofaríngeas , Infecciones por Papillomavirus , Humanos , Papillomavirus Humano 16/genética , Saliva/metabolismo , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/complicaciones , Proteínas Oncogénicas Virales/genética , Neoplasias Orofaríngeas/patología , ARN , Reacción en Cadena de la Polimerasa , Proteínas E7 de Papillomavirus/genética
7.
Biometrics ; 80(1)2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38386360

RESUMEN

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.


Asunto(s)
Obesidad Infantil , Niño , Humanos , Teorema de Bayes , Bases de Datos Factuales , Instituciones Académicas
8.
Prev Med ; 179: 107850, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38199591

RESUMEN

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.


Asunto(s)
Cannabis , Sistemas Electrónicos de Liberación de Nicotina , Uso de la Marihuana , Productos de Tabaco , Humanos , Adulto Joven , Adulto , Estudios Prospectivos , Los Angeles/epidemiología , Uso de la Marihuana/epidemiología , Uso de Tabaco/epidemiología , Violencia
9.
AIDS Behav ; 28(3): 811-819, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37792230

RESUMEN

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.


Asunto(s)
Infecciones por VIH , Alfabetización en Salud , Humanos , Anciano , Estudios Transversales , Estudios Retrospectivos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/complicaciones , Envejecimiento
10.
Biom J ; 66(1): e2200324, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37776057

RESUMEN

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.


Asunto(s)
Fragilidad , Modelos Estadísticos , Humanos , Teorema de Bayes , Biomarcadores
11.
Alzheimers Dement ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38934219

RESUMEN

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.

12.
J Environ Manage ; 350: 119644, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38000275

RESUMEN

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.


Asunto(s)
Monitoreo del Ambiente , Yacimiento de Petróleo y Gas , Energía Renovable , Combustibles Fósiles
13.
J Environ Manage ; 352: 119897, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38184869

RESUMEN

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.


Asunto(s)
Ecosistema , Yacimiento de Petróleo y Gas , Humanos , Consenso , Ambiente , Clima
14.
N Engl J Med ; 383(10): 919-930, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32877582

RESUMEN

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.).


Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Fenilbutiratos/uso terapéutico , Ácido Tauroquenodesoxicólico/uso terapéutico , Anciano , Progresión de la Enfermedad , Método Doble Ciego , Combinación de Medicamentos , Femenino , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Fenilbutiratos/efectos adversos , Índice de Severidad de la Enfermedad , Ácido Tauroquenodesoxicólico/administración & dosificación , Resultado del Tratamiento
15.
Biometrics ; 79(3): 1840-1852, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-35833874

RESUMEN

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.


Asunto(s)
Modelos Estadísticos , Humanos , Teorema de Bayes , Biomarcadores , Resultado del Tratamiento , Causalidad
16.
Prev Med ; 177: 107752, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37944672

RESUMEN

OBJECTIVE: The current broad definition of Long COVID, and an overreliance on clinical and convenience samples, is leading to a wide array of Long COVID estimates with limited generalizability. Our objective was to examine Long COVID symptoms using a statewide population-based probability sample. METHODS: Among 8000 sampled adults with polymerase-chain-reaction-confirmed SARS-CoV-2 between June 2020 and July 2021 in the Michigan Disease Surveillance System, 2533 completed our survey (response rate 32.2%). Using modified Poisson regression, we examined sociodemographic, behavioral, and clinical predictors of eight Long COVID symptom clusters, defined as at least one applicable symptom lasting 90 or more days post COVID-19 onset. RESULTS: Neuropsychiatric Long COVID symptoms, including brain fog, were most prevalent (23.7%), followed by systemic symptoms (17.1%), including fatigue, musculoskeletal (11.4%), pulmonary (10.4%), dermatologic (6.7%), cardiovascular (6.1%), gastrointestinal (5.4%), and ear, nose, and throat symptoms (5.3%). In adjusted analyses, female sex, a pre-existing psychological condition, and intensive care unit admission were strong predictors of most Long COVID symptom clusters. Older age was not associated with a higher prevalence of all symptoms - cardiovascular and dermatologic symptoms were most prevalent among middle-aged adults and age was not associated with neuropsychiatric or gastrointestinal symptoms. Additionally, there were fewer associations between pre-existing conditions and cardiovascular, neuropsychiatric, and dermatologic symptoms compared to other symptom clusters. CONCLUSIONS: While many predictors of Long COVID symptom clusters were similar, the relationship with age and pre-existing conditions varied across clusters. Cardiovascular, neuropsychiatric, and dermatologic symptoms require further study as potentially distinct from other Long COVID symptoms.


Asunto(s)
COVID-19 , Síndrome Post Agudo de COVID-19 , Adulto , Persona de Mediana Edad , Humanos , Femenino , COVID-19/epidemiología , SARS-CoV-2 , Michigan/epidemiología , Prevalencia
17.
Nicotine Tob Res ; 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38127643

RESUMEN

INTRODUCTION: Achieving cessation in people with established smoking patterns remains a challenge. Increasing cigarette prices has been one of the most effective strategies for lowering smoking rates. It remains unclear how effective it has been in encouraging cessation among adults in recent years and how the effectiveness varies by sociodemographic characteristics. 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 25+. We examine the associations between price and cessation in the population overall and by sex, race/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 effective tools for lowering smoking prevalence. It remains unclear how effective they are in encouraging adults with established smoking patterns to quit. 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.

18.
Cell ; 133(3): 393-5, 2008 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-18455977

RESUMEN

During embryonic development, large numbers of apoptotic cells are rapidly cleared by phagocytes. In this issue, Kurant et al. (2008) describe a new phagocytic receptor, called six-microns-under (SIMU), that promotes engulfment of apoptotic neurons by glial cells in the developing nervous system of Drosophila.


Asunto(s)
Proteínas de Drosophila/metabolismo , Drosophila/embriología , Proteínas de la Membrana/metabolismo , Fagocitosis , Animales , Apoptosis , Sistema Nervioso Central , Drosophila/citología , Neuroglía/metabolismo , Neuronas/citología
19.
Tob Control ; 32(5): 599-606, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-35017260

RESUMEN

SIGNIFICANCE: This study examines the differential effects of Canadian point-of-sale (POS) tobacco display bans across provinces on quit attempts and smoking cessation, by sex, education and income. METHODS: We analysed survey data from five waves (waves 4-8) of the International Tobacco Control Canada Survey, a population-based, longitudinal survey, where provinces implemented display bans between 2004 and 2010. Primary outcomes were quit attempts and successful cessation. We used generalised estimating equation Poisson regression models to estimate associations between living in a province with or without a POS ban (with a 24-month threshold) and smoking outcomes. We tested whether these associations varied by sex, education and income by including interaction terms. RESULTS: Across survey waves, the percentage of participants in provinces with POS bans established for more than 24 months increased from 5.0% to 95.8%. There was no association between POS bans and quit attempts for provinces with bans in place for 0-24 months or more than 24 months, respectively (adjusted relative risk (aRR)=0.99, 95% CI: 0.89 to 1.10; 1.03, 95% CI: 0.88 to 1.20). However, we found a differential impact of POS bans on quit attempts by sex, whereby bans were more effective for women than men for bans of 0-24 months. Participants living in a province with a POS ban for at least 24 months had a higher chance of successful cessation (aRR=1.49; 95% CI: 1.08 to 2.05) compared with those in a province without a ban. We found no differences in the association between POS bans and quit attempts or cessation by education or income, and no differences by sex for cessation. CONCLUSION: POS bans are associated with increased smoking cessation overall and more quit attempts among women than men.


Asunto(s)
Cese del Hábito de Fumar , Masculino , Humanos , Femenino , Nicotiana , Canadá/epidemiología , Fumar/epidemiología , Encuestas y Cuestionarios
20.
BMC Public Health ; 23(1): 2101, 2023 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-37880623

RESUMEN

BACKGROUND: At the beginning of the COVID-19 pandemic in the United States in the spring of 2020, many Americans avoided the healthcare system, while those with COVID-19 symptoms were faced with decisions about seeking healthcare services for this novel virus. METHODS: Using a probability sample (n = 1088) from the Michigan adult population of PCR-confirmed COVID-19 cases who were diagnosed prior to July 31, 2020, we used logistic regression to examine sociodemographic and symptom severity predictors of care-seeking behaviors. The analyses examined three different outcomes: (1) whether respondents sought care and, among those who sought care, whether they sought care from (2) a primary care provider or (3) an emergency room. Final models were adjusted for sex, age, race and ethnicity, income, education, marital status, living arrangement, health insurance, and self-reported symptom severity. RESULTS: We found that participants ages 65 and older had 4.00 times higher odds of seeking care than 18-34-year-olds (95% CI: 2.21, 7.24), while adults reporting very severe symptoms had roughly 15 times higher odds of seeking care than those with mild symptoms (95% CI: 7.73, 27.01). Adults who were non-Hispanic Black or were uninsured had lower odds of seeking care from a primary care physician versus seeking care from other locations in comparison to adults who were non-Hispanic White or were privately insured, respectively (non-Hispanic Black: aOR = 0.27, 95% CI: 0.16, 0.44; Uninsured: aOR = 0.19, 95% CI: 0.09, 0.42). Conversely, adults who were older or reported more severe symptoms had higher odds of seeking care from an emergency room versus other locations in comparison to adults who were younger or reported less severe symptoms (Age 65+: aOR = 2.96, 95% CI: 1.40, 6.28; Very Severe Symptoms: aOR = 6.63, 95% CI: 3.33, 13.20). CONCLUSIONS: Our results suggest differential utilization of healthcare services early in the COVID-19 pandemic. Further analyses are needed to examine the reasons for these differences.


Asunto(s)
COVID-19 , Adulto , Humanos , Estados Unidos , Anciano , COVID-19/epidemiología , Michigan/epidemiología , Estudios Transversales , Pandemias , Aceptación de la Atención de Salud
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