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2.
Nat Immunol ; 21(5): 513-524, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32284594

RESUMO

Oxidative stress is a central part of innate immune-induced neurodegeneration. However, the transcriptomic landscape of central nervous system (CNS) innate immune cells contributing to oxidative stress is unknown, and therapies to target their neurotoxic functions are not widely available. Here, we provide the oxidative stress innate immune cell atlas in neuroinflammatory disease and report the discovery of new druggable pathways. Transcriptional profiling of oxidative stress-producing CNS innate immune cells identified a core oxidative stress gene signature coupled to coagulation and glutathione-pathway genes shared between a microglia cluster and infiltrating macrophages. Tox-seq followed by a microglia high-throughput screen and oxidative stress gene network analysis identified the glutathione-regulating compound acivicin, with potent therapeutic effects that decrease oxidative stress and axonal damage in chronic and relapsing multiple sclerosis models. Thus, oxidative stress transcriptomics identified neurotoxic CNS innate immune populations and may enable discovery of selective neuroprotective strategies.


Assuntos
Encefalomielite Autoimune Experimental/genética , Perfilação da Expressão Gênica/métodos , Microglia/fisiologia , Esclerose Múltipla/genética , Inflamação Neurogênica/genética , Animais , Antioxidantes/uso terapêutico , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/tratamento farmacológico , Feminino , Redes Reguladoras de Genes , Ensaios de Triagem em Larga Escala , Humanos , Imunidade Inata , Isoxazóis/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Esclerose Múltipla/tratamento farmacológico , Inflamação Neurogênica/tratamento farmacológico , Estresse Oxidativo , Análise de Sequência de RNA , Análise de Célula Única
3.
Nat Immunol ; 19(11): 1212-1223, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30323343

RESUMO

Activation of innate immunity and deposition of blood-derived fibrin in the central nervous system (CNS) occur in autoimmune and neurodegenerative diseases, including multiple sclerosis (MS) and Alzheimer's disease (AD). However, the mechanisms that link disruption of the blood-brain barrier (BBB) to neurodegeneration are poorly understood, and exploration of fibrin as a therapeutic target has been limited by its beneficial clotting functions. Here we report the generation of monoclonal antibody 5B8, targeted against the cryptic fibrin epitope γ377-395, to selectively inhibit fibrin-induced inflammation and oxidative stress without interfering with clotting. 5B8 suppressed fibrin-induced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation and the expression of proinflammatory genes. In animal models of MS and AD, 5B8 entered the CNS and bound to parenchymal fibrin, and its therapeutic administration reduced the activation of innate immunity and neurodegeneration. Thus, fibrin-targeting immunotherapy inhibited autoimmunity- and amyloid-driven neurotoxicity and might have clinical benefit without globally suppressing innate immunity or interfering with coagulation in diverse neurological diseases.


Assuntos
Anticorpos Monoclonais/imunologia , Fibrinogênio/antagonistas & inibidores , Doenças Neurodegenerativas/imunologia , Animais , Epitopos , Humanos , Inflamação/imunologia , Camundongos , Ratos
4.
Nature ; 627(8003): 347-357, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38374256

RESUMO

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P < 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care.


Assuntos
Diabetes Mellitus Tipo 2 , Progressão da Doença , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Adipócitos/metabolismo , Cromatina/genética , Cromatina/metabolismo , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/genética , Diabetes Mellitus Tipo 2/classificação , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/genética , Células Endoteliais/metabolismo , Células Enteroendócrinas , Epigenômica , Predisposição Genética para Doença/genética , Ilhotas Pancreáticas/metabolismo , Herança Multifatorial/genética , Doença Arterial Periférica/complicações , Doença Arterial Periférica/genética , Análise de Célula Única
5.
Cell ; 153(1): 193-205, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23540698

RESUMO

Nucleosome remodelers of the DDM1/Lsh family are required for DNA methylation of transposable elements, but the reason for this is unknown. How DDM1 interacts with other methylation pathways, such as small-RNA-directed DNA methylation (RdDM), which is thought to mediate plant asymmetric methylation through DRM enzymes, is also unclear. Here, we show that most asymmetric methylation is facilitated by DDM1 and mediated by the methyltransferase CMT2 separately from RdDM. We find that heterochromatic sequences preferentially require DDM1 for DNA methylation and that this preference depends on linker histone H1. RdDM is instead inhibited by heterochromatin and absolutely requires the nucleosome remodeler DRD1. Together, DDM1 and RdDM mediate nearly all transposon methylation and collaborate to repress transposition and regulate the methylation and expression of genes. Our results indicate that DDM1 provides DNA methyltransferases access to H1-containing heterochromatin to allow stable silencing of transposable elements in cooperation with the RdDM pathway.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Elementos de DNA Transponíveis , Proteínas de Ligação a DNA/metabolismo , Heterocromatina , Histonas/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Regulação da Expressão Gênica de Plantas , Nucleossomos/metabolismo
6.
Mol Cell ; 77(2): 310-323.e7, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31732458

RESUMO

DNA methylation and histone H1 mediate transcriptional silencing of genes and transposable elements, but how they interact is unclear. In plants and animals with mosaic genomic methylation, functionally mysterious methylation is also common within constitutively active housekeeping genes. Here, we show that H1 is enriched in methylated sequences, including genes, of Arabidopsis thaliana, yet this enrichment is independent of DNA methylation. Loss of H1 disperses heterochromatin, globally alters nucleosome organization, and activates H1-bound genes, but only weakly de-represses transposable elements. However, H1 loss strongly activates transposable elements hypomethylated through mutation of DNA methyltransferase MET1. Hypomethylation of genes also activates antisense transcription, which is modestly enhanced by H1 loss. Our results demonstrate that H1 and DNA methylation jointly maintain transcriptional homeostasis by silencing transposable elements and aberrant intragenic transcripts. Such functionality plausibly explains why DNA methylation, a well-known mutagen, has been maintained within coding sequences of crucial plant and animal genes.


Assuntos
Proteínas de Arabidopsis/genética , Metilação de DNA/genética , Elementos de DNA Transponíveis/genética , Histonas/genética , Arabidopsis/genética , DNA (Citosina-5-)-Metiltransferases/genética , Epigênese Genética/genética , Regulação da Expressão Gênica de Plantas/genética , Inativação Gênica/fisiologia , Heterocromatina/genética , Mutação/genética , Transcrição Gênica/genética
7.
Cell ; 151(2): 289-303, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-23021777

RESUMO

Th17 cells have critical roles in mucosal defense and are major contributors to inflammatory disease. Their differentiation requires the nuclear hormone receptor RORγt working with multiple other essential transcription factors (TFs). We have used an iterative systems approach, combining genome-wide TF occupancy, expression profiling of TF mutants, and expression time series to delineate the Th17 global transcriptional regulatory network. We find that cooperatively bound BATF and IRF4 contribute to initial chromatin accessibility and, with STAT3, initiate a transcriptional program that is then globally tuned by the lineage-specifying TF RORγt, which plays a focal deterministic role at key loci. Integration of multiple data sets allowed inference of an accurate predictive model that we computationally and experimentally validated, identifying multiple new Th17 regulators, including Fosl2, a key determinant of cellular plasticity. This interconnected network can be used to investigate new therapeutic approaches to manipulate Th17 functions in the setting of inflammatory disease.


Assuntos
Redes Reguladoras de Genes , Células Th17/citologia , Células Th17/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Diferenciação Celular , Encefalomielite Autoimune Experimental/imunologia , Antígeno 2 Relacionado a Fos/imunologia , Antígeno 2 Relacionado a Fos/metabolismo , Estudo de Associação Genômica Ampla , Humanos , Fatores Reguladores de Interferon/metabolismo , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Células Th17/imunologia
8.
Trends Genet ; 39(8): 609-623, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37198063

RESUMO

Engineered gene drives create potential for both widespread benefits and irreversible harms to ecosystems. CRISPR-based systems of allelic conversion have rapidly accelerated gene drive research across diverse taxa, putting field trials and their necessary risk assessments on the horizon. Dynamic process-based models provide flexible quantitative platforms to predict gene drive outcomes in the context of system-specific ecological and evolutionary features. Here, we synthesize gene drive dynamic modeling studies to highlight research trends, knowledge gaps, and emergent principles, organized around their genetic, demographic, spatial, environmental, and implementation features. We identify the phenomena that most significantly influence model predictions, discuss limitations of biological complexity and uncertainty, and provide insights to promote responsible development and model-assisted risk assessment of gene drives.


Assuntos
Tecnologia de Impulso Genético , Ecossistema , Evolução Biológica , Medição de Risco
9.
Blood ; 143(2): 152-165, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-37832030

RESUMO

ABSTRACT: Plasmablastic lymphoma (PBL) is a rare and aggressive non-Hodgkin lymphoma associated with immunodeficiency, characterized by uncertain treatment approaches and an unfavorable prognosis. We conducted a multicenter, international, retrospective cohort study, aiming to characterize the clinical features, risk factors, and outcomes of patients with PBL. Data were collected from 22 institutions across 4 countries regarding patients diagnosed with PBL between 1 January 1999 and 31 December 2020. Survival risk factors were analyzed using both univariate and multivariate regression models. Overall survival (OS) was calculated using Kaplan-Meier statistics. First-line treatment regimens were stratified into standard- and higher-intensity regimens, and based on whether they incorporated a proteasome inhibitor (PI). A total of 281 patients (median age, 55 years) were included. Immunodeficiency of any kind was identified in 144 patients (51%), and 99 patients (35%) had HIV-positive results. The 5-year OS for the entire cohort was 36% (95% confidence interval, 30%-42%). In multivariate analysis, inferior OS was associated with Epstein-Barr virus-negative lymphoma, poor performance status, advanced stage, and bone marrow involvement. In an independent univariate analysis, the international prognostic index was associated with OS outcomes. Neither immunosuppression nor HIV infection, specifically, influenced OS. Among patients treated with curative intent (n = 234), the overall response rate was 72%. Neither the intensity of the treatment regimen nor the inclusion of PIs in first-line therapy was associated with OS. In this large retrospective study of patients with PBL, we identified novel risk factors for survival. PBL remains a challenging disease with poor long-term outcomes.


Assuntos
Infecções por Vírus Epstein-Barr , Infecções por HIV , Linfoma Plasmablástico , Humanos , Pessoa de Meia-Idade , Linfoma Plasmablástico/patologia , Estudos Retrospectivos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4 , Prognóstico
10.
EMBO J ; 40(19): e107985, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34302370

RESUMO

Monoclonal anti-SARS-CoV-2 immunoglobulins represent a treatment option for COVID-19. However, their production in mammalian cells is not scalable to meet the global demand. Single-domain (VHH) antibodies (also called nanobodies) provide an alternative suitable for microbial production. Using alpaca immune libraries against the receptor-binding domain (RBD) of the SARS-CoV-2 Spike protein, we isolated 45 infection-blocking VHH antibodies. These include nanobodies that can withstand 95°C. The most effective VHH antibody neutralizes SARS-CoV-2 at 17-50 pM concentration (0.2-0.7 µg per liter), binds the open and closed states of the Spike, and shows a tight RBD interaction in the X-ray and cryo-EM structures. The best VHH trimers neutralize even at 40 ng per liter. We constructed nanobody tandems and identified nanobody monomers that tolerate the K417N/T, E484K, N501Y, and L452R immune-escape mutations found in the Alpha, Beta, Gamma, Epsilon, Iota, and Delta/Kappa lineages. We also demonstrate neutralization of the Beta strain at low-picomolar VHH concentrations. We further discovered VHH antibodies that enforce native folding of the RBD in the E. coli cytosol, where its folding normally fails. Such "fold-promoting" nanobodies may allow for simplified production of vaccines and their adaptation to viral escape-mutations.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Mutação/imunologia , SARS-CoV-2/imunologia , Anticorpos de Domínio Único/imunologia , Animais , COVID-19/virologia , Camelídeos Americanos/imunologia , Camelídeos Americanos/virologia , Linhagem Celular , Escherichia coli/virologia , Feminino , Humanos , Glicoproteína da Espícula de Coronavírus/imunologia
11.
Development ; 149(8)2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35333324

RESUMO

Amino acid substitutions in the kinase domain of the human CSF1R gene are associated with autosomal dominant adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP). To model the human disease, we created a disease-associated mutation (pGlu631Lys; E631K) in the mouse Csf1r locus. Homozygous mutation (Csf1rE631K/E631K) phenocopied the Csf1r knockout, with prenatal mortality or severe postnatal growth retardation and hydrocephalus. Heterozygous mutation delayed the postnatal expansion of tissue macrophage populations in most organs. Bone marrow cells from Csf1rE631K/+mice were resistant to CSF1 stimulation in vitro, and Csf1rE631K/+ mice were unresponsive to administration of a CSF1-Fc fusion protein, which expanded tissue macrophage populations in controls. In the brain, microglial cell numbers and dendritic arborisation were reduced in Csf1rE631K/+ mice, as in patients with ALSP. The microglial phenotype is the opposite of microgliosis observed in Csf1r+/- mice. However, we found no evidence of brain pathology or impacts on motor function in aged Csf1rE631K/+ mice. We conclude that heterozygous disease-associated CSF1R mutations compromise CSF1R signalling. We speculate that leukoencephalopathy associated with dominant human CSF1R mutations requires an environmental trigger and/or epistatic interaction with common neurodegenerative disease-associated alleles.


Assuntos
Leucoencefalopatias , Doenças Neurodegenerativas , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos , Animais , Humanos , Leucoencefalopatias/genética , Leucoencefalopatias/patologia , Camundongos , Mutação/genética , Doenças Neurodegenerativas/patologia , Neuroglia , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética
12.
PLoS Comput Biol ; 20(1): e1011287, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38175850

RESUMO

Many pathogens of humans and livestock also infect wildlife that can act as a reservoir and challenge disease control or elimination. Efficient and effective prioritization of research and management actions requires an understanding of the potential for new tools to improve elimination probability with feasible deployment strategies that can be implemented at scale. Wildlife vaccination is gaining interest as a tool for managing several wildlife diseases. To evaluate the effect of vaccinating white-tailed deer (Odocoileus virginianus), in combination with harvest, in reducing and eliminating bovine tuberculosis from deer populations in Michigan, we developed a mechanistic age-structured disease transmission model for bovine tuberculosis with integrated disease management. We evaluated the impact of pulse vaccination across a range of vaccine properties. Pulse vaccination was effective for reducing disease prevalence rapidly with even low (30%) to moderate (60%) vaccine coverage of the susceptible and exposed deer population and was further improved when combined with increased harvest. The impact of increased harvest depended on the relative strength of transmission modes, i.e., direct vs indirect transmission. Vaccine coverage and efficacy were the most important vaccine properties for reducing and eliminating disease from the local population. By fitting the model to the core endemic area of bovine tuberculosis in Michigan, USA, we identified feasible integrated management strategies involving vaccination and increased harvest that reduced disease prevalence in free-ranging deer. Few scenarios led to disease elimination due to the chronic nature of bovine tuberculosis. A long-term commitment to regular vaccination campaigns, and further research on increasing vaccines efficacy and uptake rate in free-ranging deer are important for disease management.


Assuntos
Cervos , Mycobacterium bovis , Tuberculose Bovina , Vacinas , Animais , Humanos , Bovinos , Tuberculose Bovina/epidemiologia , Tuberculose Bovina/prevenção & controle , Animais Selvagens , Vacinação/veterinária
13.
PLoS Comput Biol ; 20(7): e1012263, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995977

RESUMO

Emerging infectious diseases with zoonotic potential often have complex socioecological dynamics and limited ecological data, requiring integration of epidemiological modeling with surveillance. Although our understanding of SARS-CoV-2 has advanced considerably since its detection in late 2019, the factors influencing its introduction and transmission in wildlife hosts, particularly white-tailed deer (Odocoileus virginianus), remain poorly understood. We use a Susceptible-Infected-Recovered-Susceptible epidemiological model to investigate the spillover risk and transmission dynamics of SARS-CoV-2 in wild and captive white-tailed deer populations across various simulated scenarios. We found that captive scenarios pose a higher risk of SARS-CoV-2 introduction from humans into deer herds and subsequent transmission among deer, compared to wild herds. However, even in wild herds, the transmission risk is often substantial enough to sustain infections. Furthermore, we demonstrate that the strength of introduction from humans influences outbreak characteristics only to a certain extent. Transmission among deer was frequently sufficient for widespread outbreaks in deer populations, regardless of the initial level of introduction. We also explore the potential for fence line interactions between captive and wild deer to elevate outbreak metrics in wild herds that have the lowest risk of introduction and sustained transmission. Our results indicate that SARS-CoV-2 could be introduced and maintained in deer herds across a range of circumstances based on testing a range of introduction and transmission risks in various captive and wild scenarios. Our approach and findings will aid One Health strategies that mitigate persistent SARS-CoV-2 outbreaks in white-tailed deer populations and potential spillback to humans.

14.
J Immunol ; 211(4): 551-562, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37341508

RESUMO

Dermal regulatory T cells (Tregs) are essential for maintenance of skin homeostasis and control of skin inflammatory responses. In mice, Tregs in the skin are characterized by high expression of CD103, the αE integrin. Evidence indicates that CD103 promotes Treg retention within the skin, although the mechanism underlying this effect is unknown. The main ligand of CD103, E-cadherin, is predominantly expressed by cells in the epidermis. However, because Tregs are predominantly located within the dermis, the nature of the interactions between E-cadherin and CD103-expressing Tregs is unclear. In this study, we used multiphoton intravital microscopy to examine the contribution of CD103 to Treg behavior in resting and inflamed skin of mice undergoing oxazolone-induced contact hypersensitivity. Inhibition of CD103 in uninflamed skin did not alter Treg behavior, whereas 48 h after inducing contact hypersensitivity by oxazolone challenge, CD103 inhibition increased Treg migration. This coincided with E-cadherin upregulation on infiltrating myeloid leukocytes in the dermis. Using CD11c-enhanced yellow fluorescent protein (EYFP) × Foxp3-GFP dual-reporter mice, inhibition of CD103 was found to reduce Treg interactions with dermal dendritic cells. CD103 inhibition also resulted in increased recruitment of effector CD4+ T cells and IFN-γ expression in challenged skin and resulted in reduced glucocorticoid-induced TNFR-related protein expression on Tregs. These results demonstrate that CD103 controls intradermal Treg migration, but only at later stages in the inflammatory response, when E-cadherin expression in the dermis is increased, and provide evidence that CD103-mediated interactions between Tregs and dermal dendritic cells support regulation of skin inflammation.


Assuntos
Dermatite de Contato , Linfócitos T Reguladores , Animais , Camundongos , Caderinas/metabolismo , Dermatite de Contato/metabolismo , Inflamação/metabolismo , Cadeias alfa de Integrinas/metabolismo , Oxazolona/metabolismo , Linfócitos T Reguladores/metabolismo
15.
Nature ; 568(7750): 88-92, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30918402

RESUMO

Agriculture and the exploitation of natural resources have transformed tropical mountain ecosystems across the world, and the consequences of these transformations for biodiversity and ecosystem functioning are largely unknown1-3. Conclusions that are derived from studies in non-mountainous areas are not suitable for predicting the effects of land-use changes on tropical mountains because the climatic environment rapidly changes with elevation, which may mitigate or amplify the effects of land use4,5. It is of key importance to understand how the interplay of climate and land use constrains biodiversity and ecosystem functions to determine the consequences of global change for mountain ecosystems. Here we show that the interacting effects of climate and land use reshape elevational trends in biodiversity and ecosystem functions on Africa's largest mountain, Mount Kilimanjaro (Tanzania). We find that increasing land-use intensity causes larger losses of plant and animal species richness in the arid lowlands than in humid submontane and montane zones. Increases in land-use intensity are associated with significant changes in the composition of plant, animal and microorganism communities; stronger modifications of plant and animal communities occur in arid and humid ecosystems, respectively. Temperature, precipitation and land use jointly modulate soil properties, nutrient turnover, greenhouse gas emissions, plant biomass and productivity, as well as animal interactions. Our data suggest that the response of ecosystem functions to land-use intensity depends strongly on climate; more-severe changes in ecosystem functioning occur in the arid lowlands and the cold montane zone. Interactions between climate and land use explained-on average-54% of the variation in species richness, species composition and ecosystem functions, whereas only 30% of variation was related to single drivers. Our study reveals that climate can modulate the effects of land use on biodiversity and ecosystem functioning, and points to a lowered resistance of ecosystems in climatically challenging environments to ongoing land-use changes in tropical mountainous regions.


Assuntos
Agricultura/estatística & dados numéricos , Altitude , Biodiversidade , Ecossistema , Clima Tropical , Animais , Umidade , Microbiologia , Plantas , Chuva , Tanzânia , Temperatura
17.
Proc Natl Acad Sci U S A ; 119(42): e2205162119, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36215497

RESUMO

Stronger amygdala-ventral prefrontal white matter connectivity has been associated with lower trait anxiety, possibly reflecting an increased capacity for efficient communication between the two regions. However, there are also reports arguing against this brain-anxiety association. To address these inconsistencies in the literature, we tested the possibility that idiosyncratic tract morphology may account for meaningful individual differences in trait anxiety, even among those with comparable microstructural integrity. Here, we adopted intersubject representational similarity analysis, an analytic framework that captures multivariate patterns of similarity, to analyze the morphological similarity of amygdala-ventral prefrontal pathways. Data drawn from the Leipzig Study for Mind-Body-Emotion Interactions dataset showed that younger adults (20 to 35 y of age) with low trait anxiety, in contrast to trait-anxious individuals, had consistently similar morphological configurations in their left amygdala-ventral prefrontal pathways. Additional tests on an independent sample of older adults (60 to 75 y of age) validated this finding. Our study reveals a generalizable pattern of brain-anxiety association that is embedded within the shared geometries between fiber tract morphology and trait anxiety data.


Assuntos
Tonsila do Cerebelo , Córtex Pré-Frontal , Idoso , Ansiedade , Transtornos de Ansiedade , Mapeamento Encefálico , Emoções , Humanos , Imageamento por Ressonância Magnética , Vias Neurais
18.
Eur Heart J ; 45(5): 366-375, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37634147

RESUMO

BACKGROUND AND AIMS: Data on new-onset atrial fibrillation (NOAF) in patients with chronic coronary syndromes (CCS) are scarce. This study aims to describe the incidence, predictors, and impact on cardiovascular (CV) outcomes of NOAF in CCS patients. METHODS: Data from the international (45 countries) CLARIFY registry (prospeCtive observational LongitudinAl RegIstry oF patients with stable coronary arterY disease) were used. Among 29 001 CCS outpatients without previously reported AF at baseline, patients with at least one episode of AF/flutter diagnosed during 5-year follow-up were compared with patients in sinus rhythm throughout the study. RESULTS: The incidence rate of NOAF was 1.12 [95% confidence interval (CI) 1.06-1.18] per 100 patient-years (cumulative incidence at 5 years: 5.0%). Independent predictors of NOAF were increasing age, increasing body mass index, low estimated glomerular filtration rate, Caucasian ethnicity, alcohol intake, and low left ventricular ejection fraction, while high triglycerides were associated with lower incidence. New-onset atrial fibrillation was associated with a substantial increase in the risk of adverse outcomes, with adjusted hazard ratios of 2.01 (95% CI 1.61-2.52) for the composite of CV death, non-fatal myocardial infarction, or non-fatal stroke, 2.61 (95% CI 2.04-3.34) for CV death, 1.64 (95% CI 1.07-2.50) for non-fatal myocardial infarction, 2.27 (95% CI 1.85-2.78) for all-cause death, 8.44 (95% CI 7.05-10.10) for hospitalization for heart failure, and 4.46 (95% CI 2.85-6.99) for major bleeding. CONCLUSIONS: Among CCS patients, NOAF is common and is strongly associated with worse outcomes. Whether more intensive preventive measures and more systematic screening for AF would improve prognosis in this population deserves further investigation.


Assuntos
Fibrilação Atrial , Infarto do Miocárdio , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/diagnóstico , Volume Sistólico , Função Ventricular Esquerda , Infarto do Miocárdio/complicações , Síndrome , Sistema de Registros , Fatores de Risco
19.
Neuroimage ; 291: 120579, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38537766

RESUMO

Very preterm (VPT) infants (born at less than 32 weeks gestational age) are at high risk for various adverse neurodevelopmental deficits. Unfortunately, most of these deficits cannot be accurately diagnosed until the age of 2-5 years old. Given the benefits of early interventions, accurate diagnosis and prediction soon after birth are urgently needed for VPT infants. Previous studies have applied deep learning models to learn the brain structural connectome (SC) to predict neurodevelopmental deficits in the preterm population. However, none of these models are specifically designed for graph-structured data, and thus may potentially miss certain topological information conveyed in the brain SC. In this study, we aim to develop deep learning models to learn the SC acquired at term-equivalent age for early prediction of neurodevelopmental deficits at 2 years corrected age in VPT infants. We directly treated the brain SC as a graph, and applied graph convolutional network (GCN) models to capture complex topological information of the SC. In addition, we applied the supervised contrastive learning (SCL) technique to mitigate the effects of the data scarcity problem, and enable robust training of GCN models. We hypothesize that SCL will enhance GCN models for early prediction of neurodevelopmental deficits in VPT infants using the SC. We used a regional prospective cohort of ∼280 VPT infants who underwent MRI examinations at term-equivalent age from the Cincinnati Infant Neurodevelopment Early Prediction Study (CINEPS). These VPT infants completed neurodevelopmental assessment at 2 years corrected age to evaluate cognition, language, and motor skills. Using the SCL technique, the GCN model achieved mean areas under the receiver operating characteristic curve (AUCs) in the range of 0.72∼0.75 for predicting three neurodevelopmental deficits, outperforming several competing models. Our results support our hypothesis that the SCL technique is able to enhance the GCN model in our prediction tasks.


Assuntos
Conectoma , Recém-Nascido Prematuro , Lactente , Recém-Nascido , Humanos , Pré-Escolar , Estudos Prospectivos , Encéfalo/diagnóstico por imagem , Recém-Nascido de muito Baixo Peso
20.
Am J Physiol Endocrinol Metab ; 326(2): E149-E165, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38117267

RESUMO

Macrophages regulate metabolic homeostasis in health and disease. Macrophage colony-stimulating factor (CSF1)-dependent macrophages contribute to homeostatic control of the size of the liver. This study aimed to determine the systemic metabolic consequences of elevating circulating CSF1. Acute administration of a CSF1-Fc fusion protein to mice led to monocytosis, increased resident tissue macrophages in the liver and all major organs, and liver growth. These effects were associated with increased hepatic glucose uptake and extensive mobilization of body fat. The impacts of CSF1 on macrophage abundance, liver size, and body composition were rapidly reversed to restore homeostasis. The effects of CSF1 on metabolism were independent of several known endocrine regulators and did not impact the physiological fasting response. Analysis using implantable telemetry in metabolic cages revealed progressively reduced body temperature and physical activity with no change in diurnal food intake. These results demonstrate the existence of a dynamic equilibrium between CSF1, the mononuclear phagocyte system, and control of liver-to-body weight ratio, which in turn controls systemic metabolic homeostasis. This novel macrophage regulatory axis has the potential to promote fat mobilization, without changes in appetence, which may have novel implications for managing metabolic syndrome.NEW & NOTEWORTHY CSF1 administration expands tissue macrophages, which transforms systemic metabolism. CSF1 drives fat mobilization and glucose uptake to support liver growth. The effects of CSF1 are independent of normal hormonal metabolic regulation. The effects of CSF1 are rapidly reversible, restoring homeostatic body composition. CSF1-dependent macrophages and liver size are coupled in a dynamic equilibrium.


Assuntos
Fator Estimulador de Colônias de Macrófagos , Macrófagos , Animais , Camundongos , Fator Estimulador de Colônias de Macrófagos/farmacologia , Fator Estimulador de Colônias de Macrófagos/metabolismo , Macrófagos/metabolismo , Metabolismo dos Carboidratos , Glucose/metabolismo , Lipídeos
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