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Brown adipose tissue (BAT) is best known for thermogenesis. Rodent studies demonstrated that enhanced BAT thermogenesis is tightly associated with increased energy expenditure, reduced body weight, and improved glucose homeostasis. However, human BAT is protective against type 2 diabetes, independent of body weight. The mechanism underlying this dissociation remains unclear. Here, we report that impaired mitochondrial catabolism of branched-chain amino acids (BCAAs) in BAT, by deleting mitochondrial BCAA carriers (MBCs), caused systemic insulin resistance without affecting energy expenditure and body weight. Brown adipocytes catabolized BCAA in the mitochondria as nitrogen donors for the biosynthesis of non-essential amino acids and glutathione. Impaired mitochondrial BCAA-nitrogen flux in BAT resulted in increased oxidative stress, decreased hepatic insulin signaling, and decreased circulating BCAA-derived metabolites. A high-fat diet attenuated BCAA-nitrogen flux and metabolite synthesis in BAT, whereas cold-activated BAT enhanced the synthesis. This work uncovers a metabolite-mediated pathway through which BAT controls metabolic health beyond thermogenesis.
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Tejido Adiposo Pardo , Aminoácidos de Cadena Ramificada , Resistencia a la Insulina , Mitocondrias , Nitrógeno , Termogénesis , Tejido Adiposo Pardo/metabolismo , Animales , Aminoácidos de Cadena Ramificada/metabolismo , Ratones , Nitrógeno/metabolismo , Mitocondrias/metabolismo , Masculino , Humanos , Metabolismo Energético , Ratones Endogámicos C57BL , Estrés Oxidativo , Insulina/metabolismo , Dieta Alta en Grasa , Adipocitos Marrones/metabolismo , Transducción de SeñalRESUMEN
Causal discovery is a powerful tool to disclose underlying structures by analyzing purely observational data. Genetic variants can provide useful complementary information for structure learning. Recently, Mendelian randomization (MR) studies have provided abundant marginal causal relationships of traits. Here, we propose a causal network pruning algorithm MRSL (MR-based structure learning algorithm) based on these marginal causal relationships. MRSL combines the graph theory with multivariable MR to learn the conditional causal structure using only genome-wide association analyses (GWAS) summary statistics. Specifically, MRSL utilizes topological sorting to improve the precision of structure learning. It proposes MR-separation instead of d-separation and three candidates of sufficient separating set for MR-separation. The results of simulations revealed that MRSL had up to 2-fold higher F1 score and 100 times faster computing time than other eight competitive methods. Furthermore, we applied MRSL to 26 biomarkers and 44 International Classification of Diseases 10 (ICD10)-defined diseases using GWAS summary data from UK Biobank. The results cover most of the expected causal links that have biological interpretations and several new links supported by clinical case reports or previous observational literatures.
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Algoritmos , Estudio de Asociación del Genoma Completo , Causalidad , Fenotipo , Transporte de Proteínas , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido SimpleRESUMEN
OBJECTIVE: To overcome the limitations associated with the collection and curation of COVID-19 outcome data in biobanks, this study proposes the use of polygenic risk scores (PRS) as reliable proxies of COVID-19 severity across three large biobanks: the Michigan Genomics Initiative (MGI), UK Biobank (UKB), and NIH All of Us. The goal is to identify associations between pre-existing conditions and COVID-19 severity. METHODS: Drawing on a sample of more than 500,000 individuals from the three biobanks, we conducted a phenome-wide association study (PheWAS) to identify associations between a PRS for COVID-19 severity, derived from a genome-wide association study on COVID-19 hospitalization, and clinical pre-existing, pre-pandemic phenotypes. We performed cohort-specific PRS PheWAS and a subsequent fixed-effects meta-analysis. RESULTS: The current study uncovered 23 pre-existing conditions significantly associated with the COVID-19 severity PRS in cohort-specific analyses, of which 21 were observed in the UKB cohort and two in the MGI cohort. The meta-analysis yielded 27 significant phenotypes predominantly related to obesity, metabolic disorders, and cardiovascular conditions. After adjusting for body mass index, several clinical phenotypes, such as hypercholesterolemia and gastrointestinal disorders, remained associated with an increased risk of hospitalization following COVID-19 infection. CONCLUSION: By employing PRS as a proxy for COVID-19 severity, we corroborated known risk factors and identified novel associations between pre-existing clinical phenotypes and COVID-19 severity. Our study highlights the potential value of using PRS when actual outcome data may be limited or inadequate for robust analyses.
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COVID-19 , Salud Poblacional , Humanos , Estudio de Asociación del Genoma Completo , Puntuación de Riesgo Genético , COVID-19/genética , Bancos de Muestras Biológicas , Cobertura de Afecciones Preexistentes , Factores de Riesgo , Predisposición Genética a la EnfermedadRESUMEN
Barth syndrome is an X-linked disorder caused by loss-of-function mutations in Tafazzin (TAZ), an acyltransferase that catalyzes remodeling of cardiolipin, a signature phospholipid of the inner mitochondrial membrane. Patients develop cardiac and skeletal muscle weakness, growth delay and neutropenia, although phenotypic expression varies considerably between patients. Taz knockout mice recapitulate many of the hallmark features of the disease. We used mouse genetics to test the hypothesis that genetic modifiers alter the phenotypic manifestations of Taz inactivation. We crossed TazKO/X females in the C57BL6/J inbred strain to males from eight inbred strains and evaluated the phenotypes of first-generation (F1) TazKO/Y progeny, compared to TazWT/Y littermates. We observed that genetic background strongly impacted phenotypic expression. C57BL6/J and CAST/EiJ[F1] TazKO/Y mice developed severe cardiomyopathy, whereas A/J[F1] TazKO/Y mice had normal heart function. C57BL6/J and WSB/EiJ[F1] TazKO/Y mice had severely reduced treadmill endurance, whereas endurance was normal in A/J[F1] and CAST/EiJ[F1] TazKO/Y mice. In all genetic backgrounds, cardiolipin showed similar abnormalities in knockout mice, and transcriptomic and metabolomic investigations identified signatures of mitochondrial uncoupling and activation of the integrated stress response. TazKO/Y cardiac mitochondria were small, clustered and had reduced cristae density in knockouts in severely affected genetic backgrounds but were relatively preserved in the permissive A/J[F1] strain. Gene expression and mitophagy measurements were consistent with reduced mitophagy in knockout mice in genetic backgrounds intolerant of Taz mutation. Our data demonstrate that genetic modifiers powerfully modulate phenotypic expression of Taz loss-of-function and act downstream of cardiolipin, possibly by altering mitochondrial quality control.
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Síndrome de Barth , Masculino , Femenino , Animales , Ratones , Síndrome de Barth/genética , Síndrome de Barth/metabolismo , Cardiolipinas/metabolismo , Factores de Transcripción/metabolismo , Modelos Animales de Enfermedad , Aciltransferasas/genética , Ratones Noqueados , FenotipoRESUMEN
Epithelial cells play a crucial role in asthma, contributing to chronic inflammation and airway hyperresponsiveness. m6A modification, which involves key proteins such as the demethylase fat mass and obesity-associated protein (FTO), is crucial in the regulation of various diseases, including asthma. However, the role of FTO in epithelial cells and the development of asthma remains unclear. In this study, we investigated the demethylase activity of FTO using a small-molecule inhibitor FB23 in epithelial cells and allergic inflammation in vivo and in vitro. We examined the FTO-regulated transcriptome-wide m6A profiling by methylated RNA immunoprecipitation sequencing (MeRIP-seq) and RNA-seq under FB23 treatment and allergic inflammation conditions. Immunofluorescence staining was performed to assess the tissue-specific expression of FTO in asthmatic bronchial mucosa. We demonstrated that FB23 alleviated allergic inflammation in IL-4/IL-13-treated epithelial cells and house dust mite (HDM)-induced allergic airway inflammation mouse model. The demethylase activity of FTO contributed to the regulation of TNF-α signaling via NF-κB and epithelial-mesenchymal transition-related pathways under allergic inflammation conditions in epithelial cells. FTO was expressed in epithelial, submucosal gland, and smooth muscle cells in human bronchial mucosa. In conclusion, FB23-induced inhibition of FTO alleviates allergic inflammation in epithelial cells and HDM-induced mice, potentially through diverse cellular processes and epithelial-mesenchymal transition signaling pathways, suggesting that FTO is a potential therapeutic target in asthma management.
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Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato , Asma , Inflamación , Animales , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/metabolismo , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Ratones , Asma/metabolismo , Asma/genética , Inflamación/metabolismo , Humanos , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/patología , Células Epiteliales/metabolismo , Ratones Endogámicos BALB C , Femenino , Hipersensibilidad/metabolismo , Hipersensibilidad/tratamiento farmacológico , Transición Epitelial-Mesenquimal/efectos de los fármacos , Ratones Endogámicos C57BLRESUMEN
Nonrandom selection in one-sample Mendelian Randomization (MR) results in biased estimates and inflated type I error rates only when the selection effects are sufficiently large. In two-sample MR, the different selection mechanisms in two samples may more seriously affect the causal effect estimation. Firstly, we propose sufficient conditions for causal effect invariance under different selection mechanisms using two-sample MR methods. In the simulation study, we consider 49 possible selection mechanisms in two-sample MR, which depend on genetic variants (G), exposures (X), outcomes (Y) and their combination. We further compare eight pleiotropy-robust methods under different selection mechanisms. Results of simulation reveal that nonrandom selection in sample II has a larger influence on biases and type I error rates than those in sample I. Furthermore, selections depending on X+Y, G+Y, or G+X+Y in sample II lead to larger biases than other selection mechanisms. Notably, when selection depends on Y, bias of causal estimation for non-zero causal effect is larger than that for null causal effect. Especially, the mode based estimate has the largest standard errors among the eight methods. In the absence of pleiotropy, selections depending on Y or G in sample II show nearly unbiased causal effect estimations when the casual effect is null. In the scenarios of balanced pleiotropy, all eight MR methods, especially MR-Egger, demonstrate large biases because the nonrandom selections result in the violation of the Instrument Strength Independent of Direct Effect (InSIDE) assumption. When directional pleiotropy exists, nonrandom selections have a severe impact on the eight MR methods. Application demonstrates that the nonrandom selection in sample II (coronary heart disease patients) can magnify the causal effect estimation of obesity on HbA1c levels. In conclusion, nonrandom selection in two-sample MR exacerbates the bias of causal effect estimation for pleiotropy-robust MR methods.
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Variación Genética , Análisis de la Aleatorización Mendeliana , Sesgo , Causalidad , Pleiotropía Genética , Humanos , Análisis de la Aleatorización Mendeliana/métodosRESUMEN
N-acyl amino acids are a large family of circulating lipid metabolites that modulate energy expenditure and fat mass in rodents. However, little is known about the regulation and potential cardiometabolic functions of N-acyl amino acids in humans. Here, we analyze the cardiometabolic phenotype associations and genomic associations of four plasma N-acyl amino acids (N-oleoyl-leucine, N-oleoyl-phenylalanine, N-oleoyl-serine, and N-oleoyl-glycine) in 2351 individuals from the Jackson Heart Study. We find that plasma levels of specific N-acyl amino acids are associated with cardiometabolic disease endpoints independent of free amino acid plasma levels and in patterns according to the amino acid head group. By integrating whole genome sequencing data with N-acyl amino acid levels, we identify that the genetic determinants of N-acyl amino acid levels also cluster according to the amino acid head group. Furthermore, we identify the CYP4F2 locus as a genetic determinant of plasma N-oleoyl-leucine and N-oleoyl-phenylalanine levels in human plasma. In experimental studies, we demonstrate that CYP4F2-mediated hydroxylation of N-oleoyl-leucine and N-oleoyl-phenylalanine results in metabolic diversification and production of many previously unknown lipid metabolites with varying characteristics of the fatty acid tail group, including several that structurally resemble fatty acid hydroxy fatty acids. These studies provide a structural framework for understanding the regulation and disease associations of N-acyl amino acids in humans and identify that the diversity of this lipid signaling family can be significantly expanded through CYP4F-mediated ω-hydroxylation.
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Aminoácidos , Familia 4 del Citocromo P450 , Ácidos Oléicos , Humanos , Aminoácidos/sangre , Aminoácidos/química , Enfermedades Cardiovasculares , Familia 4 del Citocromo P450/metabolismo , Ácidos Grasos/metabolismo , Leucina , Fenilalanina , Ácidos Oléicos/sangreRESUMEN
BACKGROUND: Patients with severe stroke often rely on surrogate decision-makers for life-sustaining treatment decisions. We investigated ethnic differences between Mexican Americans (MAs) and non-Hispanic White (NHW) individuals in surrogate reports of physician quality of communication and shared decision-making from the OASIS study (Outcomes Among Surrogate Decision Makers in Stroke) project. METHODS: Patients had ischemic stroke or intracerebral hemorrhage in Nueces County, TX. Surrogates self-identified as being involved in decisions about do-not-resuscitate orders, brain surgery, ventilator, feeding tube, or hospice/comfort care. Surrogate reports of physician quality of communication (scale score, range from 0 to 10) and shared decision-making (CollaboRATE scale score, binary score 1 versus 0) were compared by ethnicity with linear or logistic regression using generalized estimating equations, adjusted for prespecified demographics, clinical factors, and confounders. RESULTS: Between April 2016 and September 2020, 320 surrogates for 257 patients with stroke enrolled (MA, 158; NHW, 85; and other, 14). Overall quality of communication score was better among surrogates of MA patients than NHW individuals after adjustment for demographics, stroke severity, and patient survival though the ethnic difference was attenuated (ß, 0.47 [95% CI, -0.17 to 1.12]; P=0.15) after adjustment for trust in the medical profession and frequency of personal prayer. High CollaboRATE scale scores were more common among surrogates of MA patients than NHW individuals (unadjusted odds ratio, 1.75 [95% CI, 1.04-2.95]). This association persisted after adjustment for demographic and clinical factors though there was an interaction between patient age and ethnicity (P=0.04), suggesting that this difference was primarily in older patients. CONCLUSIONS: Surrogate decision-makers of MA patients generally reported better outcomes on validated measures of quality of communication and shared decision-making than NHW individuals. Further study of outcomes among diverse populations of stroke surrogate decision-makers may help to identify sources of strength and resiliency that may be broadly applicable.
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Toma de Decisiones , Accidente Cerebrovascular , Humanos , Anciano , Accidente Cerebrovascular/terapia , Hemorragia Cerebral , Órdenes de Resucitación , TexasRESUMEN
Lasso regression is widely used for large-scale propensity score (PS) estimation in healthcare database studies. In these settings, previous work has shown that undersmoothing (overfitting) Lasso PS models can improve confounding control, but it can also cause problems of non-overlap in covariate distributions. It remains unclear how to select the degree of undersmoothing when fitting large-scale Lasso PS models to improve confounding control while avoiding issues that can result from reduced covariate overlap. Here, we used simulations to evaluate the performance of using collaborative-controlled targeted learning to data-adaptively select the degree of undersmoothing when fitting large-scale PS models within both singly and doubly robust frameworks to reduce bias in causal estimators. Simulations showed that collaborative learning can data-adaptively select the degree of undersmoothing to reduce bias in estimated treatment effects. Results further showed that when fitting undersmoothed Lasso PS-models, the use of cross-fitting was important for avoiding non-overlap in covariate distributions and reducing bias in causal estimates.
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OBJECTIVE: To investigate stroke outcomes at 3, 6, and 12 months post-stroke overall and by ethnicity in a population-based, longitudinal study. METHODS: First-ever ischemic strokes (2014-2019, n = 1,332) among Mexican American persons (n = 807) and non-Hispanic white persons (n = 525) were identified from the Brain Attack Surveillance in Corpus Christi Project. Data were collected from patient or proxy interviews (baseline, 3, 6, and 12 months post-stroke) and medical records, including functional (activities of daily living/instrumental activities of daily living score), neurological (National Institutes of Health Stroke Scale), cognitive (Modified Mini-Mental State Examination), and quality of life (QOL) outcomes (12-domain Stroke-specific Quality of Life scale). Outcome trajectories were analyzed using multivariable adjusted linear models, with generalized estimating equations to account for within-subject correlations; interactions between ethnicity and time were included to investigate ethnic differences in outcomes. RESULTS: The median age was 67 years (interquartile range 58,78), 48.5% were women, and 60.6% were Mexican American persons. For all outcomes, significant improvement was seen between 3 and 6 months (p < 0.05 for all), with stability between 6 and 12 months. Mexican American persons had significantly worse outcomes compared with non-Hispanic white persons at all time points (3, 6, and 12 months), with the exception of the National Institutes of Health Stroke Scale, which did not differ by ethnicity at 6 and 12 months, and the average change in outcomes did not vary significantly by ethnicity. INTERPRETATION: Outcomes were at their worst at 3 months post-stroke, and ethnic disparities were already present, suggesting the need for early assessment and strategies to improve outcomes and possibly reduce disparities. ANN NEUROL 2023;93:348-356.
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Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Femenino , Anciano , Masculino , Etnicidad , Calidad de Vida , Actividades Cotidianas , Estudios Longitudinales , Americanos Mexicanos , Factores de RiesgoRESUMEN
BACKGROUND: Adults with type 1 or type 2 diabetes often face financial challenges and other unmet social needs to effective diabetes self-management. OBJECTIVE: Whether a digital intervention focused on addressing socioeconomic determinants of health improves diabetes clinical outcomes more than usual care. DESIGN: Randomized trial from 2019 to 2023. PARTICIPANTS: A total of 600 adults with diabetes, HbA1c ≥ 7.5%, and self-reported unmet social needs or financial burden from a health system and randomized to the intervention or standard care. INTERVENTION: CareAvenue is an automated, e-health intervention with eight videos that address unmet social needs contributing to poor outcomes. MEASURES: Primary outcome was HbA1c, measured at baseline, and 6 and 12 months after randomization. Secondary outcomes included systolic blood pressure and reported met social needs, cost-related non-adherence (CRN), and financial burden. We examined main effects and variation in effects across predefined subgroups. RESULTS: Seventy-eight percent of CareAvenue participants completed one or more modules of the website. At 12-month follow-up, there were no significant differences in HbA1c changes between CareAvenue and control group (p = 0.24). There were also no significant between-group differences in systolic blood pressure (p = 0.29), met social needs (p = 0.25), CRN (p = 0.18), and perceived financial burden (p = 0.31). In subgroup analyses, participants with household incomes 100-400% FPL (1.93 (SE = 0.76), p < 0.01), 201-400% FPL (1.30 (SE = 0.62), p < 0.04), and > 400% FPL (1.27 (SE = 0.64), p < 0.05) had significantly less A1c decreases compared to the control group. CONCLUSIONS: On average, CareAvenue participants did not achieve better A1c lowering, met needs, CRN, or perceived financial burden compared to control participants. CareAvenue participants with higher incomes achieved significantly less A1c reductions than control. Further research is needed on social needs interventions that consider tailored approaches to population subgroups. CLINICAL TRIALS REGISTRY: ClinicalTrials.gov ID NCT03950973, May 2019.
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This study aimed to examine the intraocular tolerability of the epidermal growth factor receptor antibody cetuximab, when applied intravitreally, and its effect on axial elongation. Guinea pigs aged 2-3 weeks were subjected to bilateral plano glasses and bilateral lens-induced myopization (LIM) as a single procedure for group I (n = 8) and group II (n = 8), respectively. In the animals of group III (n = 8), group IV (n = 8), and group V (n = 8), the right eyes of the animals, in addition to LIM, received four weekly intravitreal injections of cetuximab (Erbitux®) in doses of 6.25 µg, 12.5 µg, and 25 µg, respectively. As controls, the left eyes, in addition to LIM, received corresponding intraocular injections of phosphate-buffered saline. The animals underwent regular ophthalmoscopic examinations and biometry for axial length measurements. With increasing doses of cetuximab, the inter-eye difference in axial elongation (at study end, left eyes minus right eyes) were significantly the smallest in group I (0.00 ± 0.02 mm) and group II (-0.01 ± 0.02 mm), they were larger in group III (0.04 ± 0.04 mm) and group IV (0.10 ± 0.03 mm), and they were the largest in group V (0.11 ± 0.01 mm). The inter-eye difference in axial elongation enlarged (P < 0.001) with the number of injections applied. Retinal thickness at the posterior pole (right eyes) was significantly thicker in group V than in group II (P < 0.01). The density of apoptotic cells (visualized by TUNEL-staining) did not vary significantly between any of the groups (all P > 0.05). The results suggest that intravitreal injections of cetuximab in young guinea pigs with LIM resulted in a reduction in axial elongation in a dose-dependent and number of treatment-dependent manner. Intraocular toxic effects, such as intraocular inflammation, retinal thinning, or an increased density of apoptotic cells in the retina, were not observed in association with the intravitreally applied cetuximab.
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Cristalino , Miopía , Cobayas , Animales , Miopía/metabolismo , Cetuximab/toxicidad , Cetuximab/metabolismo , Retina/metabolismo , Cristalino/metabolismo , Inyecciones Intraoculares , Modelos Animales de EnfermedadRESUMEN
To infer the treatment effect for a single treated unit using panel data, synthetic control (SC) methods construct a linear combination of control units' outcomes that mimics the treated unit's pre-treatment outcome trajectory. This linear combination is subsequently used to impute the counterfactual outcomes of the treated unit had it not been treated in the post-treatment period, and used to estimate the treatment effect. Existing SC methods rely on correctly modeling certain aspects of the counterfactual outcome generating mechanism and may require near-perfect matching of the pre-treatment trajectory. Inspired by proximal causal inference, we obtain two novel nonparametric identifying formulas for the average treatment effect for the treated unit: one is based on weighting, and the other combines models for the counterfactual outcome and the weighting function. We introduce the concept of covariate shift to SCs to obtain these identification results conditional on the treatment assignment. We also develop two treatment effect estimators based on these two formulas and generalized method of moments. One new estimator is doubly robust: it is consistent and asymptotically normal if at least one of the outcome and weighting models is correctly specified. We demonstrate the performance of the methods via simulations and apply them to evaluate the effectiveness of a pneumococcal conjugate vaccine on the risk of all-cause pneumonia in Brazil.
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Simulación por Computador , Modelos Estadísticos , Vacunas Neumococicas , Humanos , Vacunas Neumococicas/uso terapéutico , Vacunas Neumococicas/administración & dosificación , Resultado del Tratamiento , Biometría/métodos , Interpretación Estadística de DatosRESUMEN
Streaming data routinely generated by social networks, mobile or web applications, e-commerce, and electronic health records present new opportunities to monitor the impact of an intervention on an outcome via causal inference methods. However, most existing causal inference methods have been focused on and applied to static data, that is, a fixed data set in which observations are pooled and stored before performing statistical analysis. There is thus a pressing need to turn static causal inference into online causal learning to support near real-time monitoring of treatment effects. In this paper, we present a framework for online estimation and inference of treatment effects that can incorporate new information as it becomes available without revisiting prior observations. We show that, under mild regularity conditions, the proposed online estimator is asymptotically equivalent to the offline oracle estimator obtained by pooling all data. Our proposal is motivated by the need for near real-time vaccine effectiveness and safety monitoring, and our proposed method is applied to a case study on COVID-19 vaccine safety surveillance.
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Vacunas contra la COVID-19 , COVID-19 , Vigilancia de Productos Comercializados , Humanos , Vigilancia de Productos Comercializados/estadística & datos numéricos , Vigilancia de Productos Comercializados/métodos , Vacunas contra la COVID-19/efectos adversos , COVID-19/prevención & control , Causalidad , Modelos Estadísticos , SARS-CoV-2 , Simulación por ComputadorRESUMEN
Data sharing barriers present paramount challenges arising from multicenter clinical studies where multiple data sources are stored and managed in a distributed fashion at different local study sites. Merging such data sources into a common data storage for a centralized statistical analysis requires a data use agreement, which is often time-consuming. Data merging may become more burdensome when propensity score modeling is involved in the analysis because combining many confounding variables, and systematic incorporation of this additional modeling in a meta-analysis has not been thoroughly investigated in the literature. Motivated from a multicenter clinical trial of basal insulin treatment for reducing the risk of post-transplantation diabetes mellitus, we propose a new inference framework that avoids the merging of subject-level raw data from multiple sites at a centralized facility but needs only the sharing of summary statistics. Unlike the architecture of federated learning, the proposed collaborative inference does not need a center site to combine local results and thus enjoys maximal protection of data privacy and minimal sensitivity to unbalanced data distributions across data sources. We show theoretically and numerically that the new distributed inference approach has little loss of statistical power compared to the centralized method that requires merging the entire data. We present large-sample properties and algorithms for the proposed method. We illustrate its performance by simulation experiments and the motivating example on the differential average treatment effect of basal insulin to lower risk of diabetes among kidney-transplant patients compared to the standard-of-care.
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Estudios Multicéntricos como Asunto , Humanos , Difusión de la Información , Diabetes Mellitus/terapia , Simulación por Computador , Modelos Estadísticos , Insulina/uso terapéutico , Puntaje de Propensión , Resultado del Tratamiento , Hipoglucemiantes/uso terapéuticoRESUMEN
BACKGROUND: The incidence of Talaromyces marneffei (T. marneffei) infection has increased in recent years with the development of organ transplantation and the widespread use of immunosuppressive agents. However, the lack of clinical suspicion leading to delay or misdiagnosis is an important reason for the high mortality rate in non-human immunodeficiency virus (HIV) and non-endemic population. Herein, we report a case of disseminated T. marneffei infection in a non-HIV and non-endemic recipient after renal transplant, who initially presented with skin rashes and subcutaneous nodules and developed gastrointestinal bleeding. CASE PRESENTATION: We describe a 54-year-old renal transplantation recipient presented with scattered rashes, subcutaneous nodules and ulcerations on the head, face, abdomen, and right upper limb. The HIV antibody test was negative. The patient had no obvious symptoms such as fever, cough, etc. Histopathological result of the skin lesion sites showed chronic suppurative inflammation with a large number of fungal spores. Subsequent fungal culture suggested T. marneffei infection. Amphotericin B deoxycholate was given for antifungal treatment, and there was no deterioration in the parameters of liver and kidney function. Unfortunately, the patient was soon diagnosed with gastrointestinal bleeding, gastrointestinal perforation and acute peritonitis. Then he rapidly developed multiple organ dysfunction syndrome and abandoned treatment. CONCLUSIONS: The risk of fatal gastrointestinal bleeding can be significantly increased in kidney transplant patients with T. marneffei infection because of the long-term side effects of post-transplant medications. Strengthening clinical awareness and using mNGS or mass spectrometry technologies to improve the detection rate and early diagnosis of T. marneffei are crucial for clinical treatment in non-HIV and non-endemic population.
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Trasplante de Riñón , Micosis , Talaromyces , Receptores de Trasplantes , Humanos , Masculino , Persona de Mediana Edad , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Ácido Desoxicólico , Dermatomicosis/diagnóstico , Dermatomicosis/microbiología , Dermatomicosis/tratamiento farmacológico , Combinación de Medicamentos , Resultado Fatal , Trasplante de Riñón/efectos adversos , Micosis/diagnóstico , Micosis/tratamiento farmacológico , Micosis/microbiología , Talaromyces/aislamiento & purificaciónRESUMEN
Secondary organic aerosol (SOA) formation from gasoline vehicles spanning a wide range of emission types was investigated using an oxidation flow reactor (OFR) by conducting chassis dynamometer tests. Aided by advanced mass spectrometric techniques, SOA precursors, including volatile organic compounds (VOCs) and intermediate/semivolatile organic compounds (I/SVOCs), were comprehensively characterized. The reconstructed SOA produced from the speciated VOCs and I/SVOCs can explain 69% of the SOA measured downstream of an OFR upon 0.5-3 days' OH exposure. While VOCs can only explain 10% of total SOA production, the contribution from I/SVOCs is 59%, with oxygenated I/SVOCs (O-I/SVOCs) taking up 20% of that contribution. O-I/SVOCs (e.g., benzylic or aliphatic aldehydes and ketones), as an obscured source, account for 16% of total nonmethane organic gas (NMOG) emission. More importantly, with the improvement in emission standards, the NMOG is effectively mitigated by 35% from China 4 to China 6, which is predominantly attributed to the decrease of VOCs. Real-time measurements of different NMOG components as well as SOA production further reveal that the current emission control measures, such as advances in engine and three-way catalytic converter (TWC) techniques, are effective in reducing the "light" SOA precursors (i.e., single-ring aromatics) but not for the I/SVOC emissions. Our results also highlight greater effects of O-I/SVOCs to SOA formation than previously observed and the urgent need for further investigation into their origins, i.e., incomplete combustion, lubricating oil, etc., which requires improvements in real-time molecular-level characterization of I/SVOC molecules and in turn will benefit the future design of control measures.
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Aerosoles , Gasolina , Emisiones de Vehículos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/química , Compuestos Orgánicos/químicaRESUMEN
C/EBP homologous protein (CHOP) triggers the death of multiple cancers via endoplasmic reticulum (ER) stress. However, the function and regulatory mechanism of CHOP in liver cancer remain elusive. We have reported that late endosomal/lysosomal adapter, mitogen-activated protein kinase and mTOR activator 5 (LAMTOR5) suppresses apoptosis in various cancers. Here, we show that the transcriptional and posttranscriptional inactivation of CHOP mediated by LAMTOR5 accelerates liver cancer growth. Clinical bioinformatic analysis revealed that the expression of CHOP was low in liver cancer tissues and that its increased expression predicted a good prognosis. Elevated CHOP contributed to destruction of LAMTOR5-induced apoptotic suppression and proliferation. Mechanistically, LAMTOR5-recruited DNA methyltransferase 1 (DNMT1) to the CpG3 region (-559/-429) of the CHOP promoter and potentiated its hypermethylation to block its interaction with general transcription factor IIi (TFII-I), resulting in its inactivation. Moreover, LAMTOR5-enhanced miR-182/miR-769 reduced CHOP expression by targeting its 3'UTR. Notably, lenvatinib, a first-line targeted therapy for liver cancer, could target the LAMTOR5/CHOP axis to prevent liver cancer progression. Accordingly, LAMTOR5-mediated silencing of CHOP via the regulation of ER stress-related apoptosis promotes liver cancer growth, providing a theoretical basis for the use of lenvatinib for the treatment of liver cancer.
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BACKGROUND: Previous studies have indicated a possible link between obesity and myopia, although the results have varied. The objective of this study was to investigate the correlation between a new measure of obesity, the weight-adjusted waist index (WWI), and myopia. METHOD: This cross-sectional study included individuals between the ages of 12 and 25 who participated in a noncycloplegic vision examination as part of the National Health and Nutrition Examination Survey (NHANES) conducted from 1999 to 2008. WWI was calculated as waist circumference divided by the square root of body weight. Myopia was characterized by a spherical equivalent (SE) of ≤ - 0.5 diopters (D) and further categorized into mild (-3.00D < SE≤-0.50 D), moderate (-6.00D < SE ≤-3.00 D), or high (SE≤-6.00 D). We utilized a weighted multivariable logistic regression and a generalized additive model to evaluate the correlation between WWI and myopia. Threshold effects were analyzed, and we performed subgroup analysis and interaction tests. RESULTS: A grand total of 11,180 individuals were registered for the study. Decreased myopia severity was observed with higher WWI, as evidenced by elevated SE (ß = 0.098, 95% CI: 0.028-0.167). Individuals in the top tertile of WWI experienced a 19.8% decrease in risk compared to those in the lowest group (OR = 0.802, 95% CI: 0.800-0.804; P for trend < 0.001). Similar associations were observed for high myopia. Gender-specific nonlinear associations were found, with different breakpoints for males (10.774) and females (10.025). In males, a significant positive association was found on the right side of the breakpoint (OR = 1.398, 95% CI: 1.038-1.884), while no significant association was found on the left side. Conversely, among females, a negative association was observed on the left side of the breakpoint (OR = 0.679, 95% CI: 0.512-0.899), whereas no notable correlation was detected on the right side. CONCLUSION: Increased WWI level was linked to a lower risk of myopia and high myopia in the overall sample, with gender-specific variations.
Asunto(s)
Miopía , Femenino , Masculino , Humanos , Adolescente , Adulto Joven , Niño , Adulto , Estudios Transversales , Encuestas Nutricionales , Miopía/diagnóstico , Miopía/epidemiología , Obesidad/epidemiología , Refracción OcularRESUMEN
BACKGROUND: To investigate the relationship between body weight and Axial length in guinea pigs. METHODS: Forty pigmented guinea pigs were randomly divided into two groups, namely control group and negative lens-induced myopization (LIM) group. After measuring the baseline axial length and body weight (BW), guinea pigs of LIM group received bilateral negative lens-induced myopization using - 10.0 diopters lenses. One week later, the lenses were removed and biometric and ophthalmoscopic examinations were repeated. RESULTS: Two groups of guinea pigs showed no statistical difference in initial body weight and eye axis length. Compared to the control group, the lens-induced group had a lower weight (P = 0.02) and a longer axial length (P < 0.01) at the end of study Neither at baseline nor at week 1 did AL correlate with BW in both groups (Control Baseline: r = 0.306, P = 0.19; Control Week1: r = 0.333, P = 0.15; LIM Baseline: r=-0.142, P = 0.55; LIM Week 1: r = 0.189, P = 0.42). Lens-induction had a significant effect on axial elongation (P < 0.01) while body weight had no impact on such aspect (P > 0.05). CONCLUSION: In guinea pigs of the same age, axial length was not correlated with body weight. Also, baseline body weight had no impact on natural axial length growth or lens-induced myopia. Lens-induction caused a significant reduction in body weight gain.