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1.
Cell ; 183(4): 935-953.e19, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33186530

RESUMO

Neurons are frequently classified into distinct types on the basis of structural, physiological, or genetic attributes. To better constrain the definition of neuronal cell types, we characterized the transcriptomes and intrinsic physiological properties of over 4,200 mouse visual cortical GABAergic interneurons and reconstructed the local morphologies of 517 of those neurons. We find that most transcriptomic types (t-types) occupy specific laminar positions within visual cortex, and, for most types, the cells mapping to a t-type exhibit consistent electrophysiological and morphological properties. These properties display both discrete and continuous variation among t-types. Through multimodal integrated analysis, we define 28 met-types that have congruent morphological, electrophysiological, and transcriptomic properties and robust mutual predictability. We identify layer-specific axon innervation pattern as a defining feature distinguishing different met-types. These met-types represent a unified definition of cortical GABAergic interneuron types, providing a systematic framework to capture existing knowledge and bridge future analyses across different modalities.


Assuntos
Córtex Cerebral/citologia , Fenômenos Eletrofisiológicos , Neurônios GABAérgicos/citologia , Neurônios GABAérgicos/metabolismo , Transcriptoma/genética , Animais , Feminino , Perfilação da Expressão Gênica , Hipocampo/fisiologia , Canais Iônicos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/metabolismo
2.
Nature ; 598(7879): 151-158, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34616067

RESUMO

The neocortex is disproportionately expanded in human compared with mouse1,2, both in its total volume relative to subcortical structures and in the proportion occupied by supragranular layers composed of neurons that selectively make connections within the neocortex and with other telencephalic structures. Single-cell transcriptomic analyses of human and mouse neocortex show an increased diversity of glutamatergic neuron types in supragranular layers in human neocortex and pronounced gradients as a function of cortical depth3. Here, to probe the functional and anatomical correlates of this transcriptomic diversity, we developed a robust platform combining patch clamp recording, biocytin staining and single-cell RNA-sequencing (Patch-seq) to examine neurosurgically resected human tissues. We demonstrate a strong correspondence between morphological, physiological and transcriptomic phenotypes of five human glutamatergic supragranular neuron types. These were enriched in but not restricted to layers, with one type varying continuously in all phenotypes across layers 2 and 3. The deep portion of layer 3 contained highly distinctive cell types, two of which express a neurofilament protein that labels long-range projection neurons in primates that are selectively depleted in Alzheimer's disease4,5. Together, these results demonstrate the explanatory power of transcriptomic cell-type classification, provide a structural underpinning for increased complexity of cortical function in humans, and implicate discrete transcriptomic neuron types as selectively vulnerable in disease.


Assuntos
Ácido Glutâmico/metabolismo , Neocórtex/citologia , Neocórtex/crescimento & desenvolvimento , Neurônios/citologia , Neurônios/metabolismo , Doença de Alzheimer , Animais , Forma Celular , Colágeno/metabolismo , Eletrofisiologia , Proteínas da Matriz Extracelular/metabolismo , Feminino , Humanos , Lisina/análogos & derivados , Masculino , Camundongos , Neocórtex/anatomia & histologia , Neurônios/classificação , Técnicas de Patch-Clamp , Transcriptoma
3.
N Engl J Med ; 387(7): 599-610, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-36070710

RESUMO

BACKGROUND: Early treatment to prevent severe coronavirus disease 2019 (Covid-19) is an important component of the comprehensive response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. METHODS: In this phase 3, double-blind, randomized, placebo-controlled trial, we used a 2-by-3 factorial design to test the effectiveness of three repurposed drugs - metformin, ivermectin, and fluvoxamine - in preventing serious SARS-CoV-2 infection in nonhospitalized adults who had been enrolled within 3 days after a confirmed diagnosis of infection and less than 7 days after the onset of symptoms. The patients were between the ages of 30 and 85 years, and all had either overweight or obesity. The primary composite end point was hypoxemia (≤93% oxygen saturation on home oximetry), emergency department visit, hospitalization, or death. All analyses used controls who had undergone concurrent randomization and were adjusted for SARS-CoV-2 vaccination and receipt of other trial medications. RESULTS: A total of 1431 patients underwent randomization; of these patients, 1323 were included in the primary analysis. The median age of the patients was 46 years; 56% were female (6% of whom were pregnant), and 52% had been vaccinated. The adjusted odds ratio for a primary event was 0.84 (95% confidence interval [CI], 0.66 to 1.09; P = 0.19) with metformin, 1.05 (95% CI, 0.76 to 1.45; P = 0.78) with ivermectin, and 0.94 (95% CI, 0.66 to 1.36; P = 0.75) with fluvoxamine. In prespecified secondary analyses, the adjusted odds ratio for emergency department visit, hospitalization, or death was 0.58 (95% CI, 0.35 to 0.94) with metformin, 1.39 (95% CI, 0.72 to 2.69) with ivermectin, and 1.17 (95% CI, 0.57 to 2.40) with fluvoxamine. The adjusted odds ratio for hospitalization or death was 0.47 (95% CI, 0.20 to 1.11) with metformin, 0.73 (95% CI, 0.19 to 2.77) with ivermectin, and 1.11 (95% CI, 0.33 to 3.76) with fluvoxamine. CONCLUSIONS: None of the three medications that were evaluated prevented the occurrence of hypoxemia, an emergency department visit, hospitalization, or death associated with Covid-19. (Funded by the Parsemus Foundation and others; COVID-OUT ClinicalTrials.gov number, NCT04510194.).


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Fluvoxamina , Ivermectina , Metformina , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/complicações , Vacinas contra COVID-19 , Método Duplo-Cego , Feminino , Fluvoxamina/uso terapêutico , Humanos , Hipóxia/etiologia , Ivermectina/uso terapêutico , Masculino , Metformina/uso terapêutico , Pessoa de Meia-Idade , Obesidade/complicações , Sobrepeso/complicações , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , SARS-CoV-2
4.
BMC Bioinformatics ; 25(1): 64, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331751

RESUMO

Functional analysis of high throughput experiments using pathway analysis is now ubiquitous. Though powerful, these methods often produce thousands of redundant results owing to knowledgebase redundancies upstream. This scale of results hinders extensive exploration by biologists and can lead to investigator biases due to previous knowledge and expectations. To address this issue, we present vissE, a flexible network-based analysis and visualisation tool that organises information into semantic categories and provides various visualisation modules to characterise them with respect to the underlying data, thus providing a comprehensive view of the biological system. We demonstrate vissE's versatility by applying it to three different technologies: bulk, single-cell and spatial transcriptomics. Applying vissE to a factor analysis of a breast cancer spatial transcriptomic data, we identified stromal phenotypes that support tumour dissemination. Its adaptability allows vissE to enhance all existing gene-set enrichment and pathway analysis workflows, empowering biologists during molecular discovery.


Assuntos
Neoplasias da Mama , Perfilação da Expressão Gênica , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Transcriptoma , Fenótipo
5.
Clin Infect Dis ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690892

RESUMO

BACKGROUND: Metformin has antiviral activity against RNA viruses including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The mechanism appears to be suppression of protein translation via targeting the host mechanistic target of rapamycin pathway. In the COVID-OUT randomized trial for outpatient coronavirus disease 2019 (COVID-19), metformin reduced the odds of hospitalizations/death through 28 days by 58%, of emergency department visits/hospitalizations/death through 14 days by 42%, and of long COVID through 10 months by 42%. METHODS: COVID-OUT was a 2 × 3 randomized, placebo-controlled, double-blind trial that assessed metformin, fluvoxamine, and ivermectin; 999 participants self-collected anterior nasal swabs on day 1 (n = 945), day 5 (n = 871), and day 10 (n = 775). Viral load was quantified using reverse-transcription quantitative polymerase chain reaction. RESULTS: The mean SARS-CoV-2 viral load was reduced 3.6-fold with metformin relative to placebo (-0.56 log10 copies/mL; 95% confidence interval [CI], -1.05 to -.06; P = .027). Those who received metformin were less likely to have a detectable viral load than placebo at day 5 or day 10 (odds ratio [OR], 0.72; 95% CI, .55 to .94). Viral rebound, defined as a higher viral load at day 10 than day 5, was less frequent with metformin (3.28%) than placebo (5.95%; OR, 0.68; 95% CI, .36 to 1.29). The metformin effect was consistent across subgroups and increased over time. Neither ivermectin nor fluvoxamine showed effect over placebo. CONCLUSIONS: In this randomized, placebo-controlled trial of outpatient treatment of SARS-CoV-2, metformin significantly reduced SARS-CoV-2 viral load, which may explain the clinical benefits in this trial. Metformin is pleiotropic with other actions that are relevant to COVID-19 pathophysiology. CLINICAL TRIALS REGISTRATION: NCT04510194.

6.
Eur Radiol ; 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38189982

RESUMO

BACKGROUND: Coronary artery disease (CAD) and severe aortic valve stenosis (AS) frequently coexist. While pre-transcatheter aortic valve replacement (TAVR) computed tomography angiography (CTA) allows to rule out obstructive CAD, interpreting hemodynamic significance of intermediate stenoses is challenging. This study investigates the incremental value of CT-derived fractional flow reserve (CT-FFR), quantitative coronary plaque characteristics (e.g., stenosis degree, plaque volume, and composition), and peri-coronary adipose tissue (PCAT) density to detect hemodynamically significant lesions among those with AS and CAD. MATERIALS AND METHODS: We included patients with severe AS and intermediate coronary lesions (20-80% diameter stenosis) who underwent pre-TAVR CTA and invasive coronary angiogram (ICA) with resting full-cycle ratio (RFR) assessment between 08/16 and 04/22. CTA image analysis included assessment of CT-FFR, quantitative coronary plaque analysis, and PCAT density. Coronary lesions with RFR ≤ 0.89 indicated hemodynamic significance as reference standard. RESULTS: Overall, 87 patients (age 77.9 ± 7.4 years, 38% female) with 95 intermediate coronary artery lesions were included. CT-FFR showed good discriminatory capacity (area under receiver operator curve (AUC) = 0.89, 95% confidence interval (CI) 0.81-0.96, p < 0.001) to identify hemodynamically significant lesions, superior to anatomical assessment, plaque morphology, and PCAT density. Plaque composition and PCAT density did not differ between lesions with and without hemodynamic significance. Univariable and multivariable analyses revealed CT-FFR as the only predictor for functionally significant lesions (odds ratio 1.28 (95% CI 1.17-1.43), p < 0.001). Overall, CT-FFR ≤ 0.80 showed diagnostic accuracy, sensitivity, and specificity of 88.4% (95%CI 80.2-94.1), 78.5% (95%CI 63.2-89.7), and 96.2% (95%CI 87.0-99.5), respectively. CONCLUSION: CT-FFR was superior to CT anatomical, plaque morphology, and PCAT assessment to detect functionally significant stenoses in patients with severe AS. CLINICAL RELEVANCE STATEMENT: CT-derived fractional flow reserve in patients with severe aortic valve stenosis may be a useful tool for non-invasive hemodynamic assessment of intermediate coronary lesions, while CT anatomical, plaque morphology, and peri-coronary adipose tissue assessment have no incremental or additional benefit. These findings might help to reduce pre-transcatheter aortic valve replacement invasive coronary angiogram. KEY POINTS: • Interpreting the hemodynamic significance of intermediate coronary stenoses is challenging in pre-transcatheter aortic valve replacement CT. • CT-derived fractional flow reserve (CT-FFR) has a good discriminatory capacity in the identification of hemodynamically significant coronary lesions. • CT-derived anatomical, plaque morphology, and peri-coronary adipose tissue assessment did not improve the diagnostic capability of CT-FFR in the hemodynamic assessment of intermediate coronary stenoses.

7.
Arterioscler Thromb Vasc Biol ; 43(11): 2165-2178, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37675637

RESUMO

BACKGROUND: SR-B1 (scavenger receptor class B type 1)/LDLR (low-density lipoprotein receptor) double knockout mice fed a high-fat, high-cholesterol diet containing cholate exhibit coronary artery disease characterized by occlusive coronary artery atherosclerosis, platelet accumulation in coronary arteries, and myocardial fibrosis. Platelets are involved in atherosclerosis development, and PAR (protease-activated receptor) 4 has a prominent role in platelet function in mice. However, the role of PAR4 on coronary artery disease in mice has not been tested. METHODS: We tested the effects of a PAR4 inhibitory pepducin (RAG8) on diet-induced aortic sinus and coronary artery atherosclerosis, platelet accumulation in atherosclerotic coronary arteries, and myocardial fibrosis in SR-B1/LDLR double knockout mice. SR-B1/LDLR double knockout mice were fed a high-fat, high-cholesterol diet containing cholate and injected daily with 20 mg/kg of either the RAG8 pepducin or a control reverse-sequence pepducin (SRQ8) for 20 days. RESULTS: Platelets from the RAG8-treated mice exhibited reduced thrombin and PAR4 agonist peptide-mediated activation compared with those from control SRQ8-treated mice when tested ex vivo. Although aortic sinus atherosclerosis levels did not differ, RAG8-treated mice exhibited reduced coronary artery atherosclerosis, reduced platelet accumulation in atherosclerotic coronary arteries, and reduced myocardial fibrosis. These protective effects were not accompanied by changes in circulating lipids, inflammatory cytokines, or immune cells. However, RAG8-treated mice exhibited reduced VCAM-1 (vascular cell adhesion molecule 1) protein levels in nonatherosclerotic coronary artery cross sections and reduced leukocyte accumulation in atherosclerotic coronary artery cross sections compared with those from SRQ8-treated mice. CONCLUSIONS: The PAR4 inhibitory RAG8 pepducin reduced coronary artery atherosclerosis and myocardial fibrosis in SR-B1/LDLR double knockout mice fed a high-fat, high-cholesterol diet containing cholate. Furthermore, RAG8 reduced VCAM-1 in nonatherosclerotic coronary arteries and reduced leukocyte and platelet accumulation in atherosclerotic coronary arteries. These findings identify PAR4 as an attractive target in reducing coronary artery disease development, and the use of RAG8 may potentially be beneficial in cardiovascular disease.


Assuntos
Aterosclerose , Doença da Artéria Coronariana , Animais , Camundongos , Aterosclerose/genética , Aterosclerose/prevenção & controle , Aterosclerose/metabolismo , Colatos , Colesterol , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/prevenção & controle , Fibrose , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de LDL/genética , Receptores de LDL/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
8.
Cell Mol Life Sci ; 80(2): 39, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36629912

RESUMO

Non-alcoholic steatohepatitis (NASH) is associated with obesity and increased expression of hepatic peroxisome proliferator-activated receptor γ (PPARγ). However, the relevance of hepatocyte PPARγ in NASH associated with obesity is still poorly understood. In this study, hepatocyte PPARγ was knocked out (PpargΔHep) in male and female mice after the development of high-fat diet-induced obesity. The diet-induced obese mice were then maintained on their original diet or switched to a high fat, cholesterol, and fructose (HFCF) diet to induce NASH. Hepatic PPARγ expression was mostly derived from hepatocytes and increased by high fat diets. PpargΔHep reduced HFCF-induced NASH progression without altering steatosis, reduced the expression of key genes involved in hepatic fibrosis in HFCF-fed male and female mice, and decreased the area of collagen-stained fibrosis in the liver of HFCF-fed male mice. Moreover, transcriptomic and metabolomic data suggested that HFCF-diet regulated hepatic amino acid metabolism in a hepatocyte PPARγ-dependent manner. PpargΔHep increased betaine-homocysteine s-methyltransferase expression and reduced homocysteine levels in HFCF-fed male mice. In addition, in a cohort of 102 obese patients undergoing bariatric surgery with liver biopsies, 16 cases were scored with NASH and were associated with increased insulin resistance and hepatic PPARγ expression. Our study shows that hepatocyte PPARγ expression is associated with NASH in mice and humans. In male mice, hepatocyte PPARγ negatively regulates methionine metabolism and contributes to the progression of fibrosis.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Masculino , Feminino , Animais , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Camundongos Obesos , Hepatócitos/metabolismo , Fígado/metabolismo , Cirrose Hepática/metabolismo , Obesidade/metabolismo , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
9.
Eur Heart J ; 44(12): 1040-1054, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36300362

RESUMO

AIMS: This network meta-analysis aimed to assess the effect of early coronary angiography (CAG) compared with selective CAG (late and no CAG) for patients after out-of-hospital cardiac arrest without ST-elevation myocardial infarction (NSTE-OHCA). METHODS AND RESULTS: A systematic literature search was performed using the EMBASE, MEDLINE and Web of Science databases without restrictions on publication date. The last search was performed on 15 July 2022. Randomized controlled trials (RCTs) and non-randomized studies (NRS) comparing the effect of early CAG to selective CAG after NSTE-OHCA on survival and/or neurological outcomes were included. Meta-analyses were performed based on a DerSimonian-Laird random effects model. A total of 18 studies were identified by the literature search. After the exclusion of two studies due to high risk of bias, 16 studies (six RCTs, ten NRS) were included in the final analyses. Meta-analyses showed a statistically significant increase in survival after early CAG compared with selective CAG in the overall analysis [OR: 1.40, 95% confidence interval (CI): (1.12-1.76), P < 0.01, I2 = 68%]. This effect was lost in the subgroup analysis of RCTs [OR: 0.89, 95% CI: (0.73-1.10), P = 0.29, I2 = 0%]. Random effects model network meta-analysis of NRS based on a Bayesian method showed statistically significant increased survival after late compared with early CAG [OR: 4.20, 95% CI: (1.22, 20.91)]. CONCLUSION: The previously reported superiority of early CAG after NSTE-OHCA is based on NRS at high risk of selection and survivorship bias. The meta-analysis of RCTs does not support routinely performing early CAG after NSTE-OHCA.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca Extra-Hospitalar , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Reanimação Cardiopulmonar/métodos , Angiografia Coronária/métodos , Metanálise em Rede , Parada Cardíaca Extra-Hospitalar/diagnóstico por imagem , Parada Cardíaca Extra-Hospitalar/terapia , Intervenção Coronária Percutânea/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem
10.
Sensors (Basel) ; 24(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38931570

RESUMO

Conventional passive ankle foot orthoses (AFOs) have not seen substantial advances or functional improvements for decades, failing to meet the demands of many stakeholders, especially the pediatric population with neurological disorders. Our objective is to develop the first comfortable and unobtrusive powered AFO for children with cerebral palsy (CP), the DE-AFO. CP is the most diagnosed neuromotor disorder in the pediatric population. The standard of care for ankle control dysfunction associated with CP, however, is an unmechanized, bulky, and uncomfortable L-shaped conventional AFO. These passive orthoses constrain the ankle's motion and often cause muscle disuse atrophy, skin damage, and adverse neural adaptations. While powered orthoses could enhance natural ankle motion, their reliance on bulky, noisy, and rigid actuators like DC motors limits their acceptability. Our innovation, the DE-AFO, emerged from insights gathered during customer discovery interviews with 185 stakeholders within the AFO ecosystem as part of the NSF I-Corps program. The DE-AFO is a biomimetic robot that employs artificial muscles made from an electro-active polymer called dielectric elastomers (DEs) to assist ankle movements in the sagittal planes. It incorporates a gait phase detection controller to synchronize the artificial muscles with natural gait cycles, mimicking the function of natural ankle muscles. This device is the first of its kind to utilize lightweight, compact, soft, and silent artificial muscles that contract longitudinally, addressing traditional actuated AFOs' limitations by enhancing the orthosis's natural feel, comfort, and acceptability. In this paper, we outline our design approach and describe the three main components of the DE-AFO: the artificial muscle technology, the finite state machine (the gait phase detection system), and its mechanical structure. To verify the feasibility of our design, we theoretically calculated if DE-AFO can provide the necessary ankle moment assistance for children with CP-aligning with moments observed in typically developing children. To this end, we calculated the ankle moment deficit in a child with CP when compared with the normative moment of seven typically developing children. Our results demonstrated that the DE-AFO can provide meaningful ankle moment assistance, providing up to 69% and 100% of the required assistive force during the pre-swing phase and swing period of gait, respectively.


Assuntos
Tornozelo , Paralisia Cerebral , Órtoses do Pé , Robótica , Paralisia Cerebral/fisiopatologia , Paralisia Cerebral/reabilitação , Humanos , Criança , Robótica/métodos , Tornozelo/fisiopatologia , Tornozelo/fisiologia , Elastômeros/química , Marcha/fisiologia , Desenho de Equipamento , Fenômenos Biomecânicos
11.
Int J Mol Sci ; 25(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38892040

RESUMO

Cirrhotic cardiomyopathy (CCM) is defined as cardiac dysfunction associated with cirrhosis in the absence of pre-existing heart disease. CCM manifests as the enlargement of cardiac chambers, attenuated systolic and diastolic contractile responses to stress stimuli, and repolarization changes. CCM significantly contributes to mortality and morbidity in patients who undergo liver transplantation and contributes to the pathogenesis of hepatorenal syndrome/acute kidney injury. There is currently no specific treatment. The traditional management for non-cirrhotic cardiomyopathies, such as vasodilators or diuretics, is not applicable because an important feature of cirrhosis is decreased systemic vascular resistance; therefore, vasodilators further worsen the peripheral vasodilatation and hypotension. Long-term diuretic use may cause electrolyte imbalances and potentially renal injury. The heart of the cirrhotic patient is insensitive to cardiac glycosides. Therefore, these types of medications are not useful in patients with CCM. Exploring the therapeutic strategies of CCM is of the utmost importance. The present review summarizes the possible treatment of CCM. We detail the current status of non-selective beta-blockers (NSBBs) in the management of cirrhotic patients and discuss the controversies surrounding NSBBs in clinical practice. Other possible therapeutic agents include drugs with antioxidant, anti-inflammatory, and anti-apoptotic functions; such effects may have potential clinical application. These drugs currently are mainly based on animal studies and include statins, taurine, spermidine, galectin inhibitors, albumin, and direct antioxidants. We conclude with speculations on the future research directions in CCM treatment.


Assuntos
Cardiomiopatias , Cirrose Hepática , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , Cardiomiopatias/terapia , Cardiomiopatias/etiologia , Animais , Antagonistas Adrenérgicos beta/uso terapêutico , Antioxidantes/uso terapêutico
12.
Am J Physiol Cell Physiol ; 325(1): C29-C41, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37212549

RESUMO

Peroxisome proliferator-activated receptor γ (PPARγ) plays a pivotal role in regulating lipid metabolism and hepatic PPARγ transactivation contributes to fatty liver development. Fatty acids (FAs) are well-known endogenous ligands for PPARγ. Palmitate, a 16-C saturated FA (SFA) and the most abundant SFA in human circulation, is a strong inducer of hepatic lipotoxicity, a central pathogenic factor for various fatty liver diseases. In this study, using both alpha mouse liver 12 (AML12) and primary mouse hepatocytes, we investigated the effects of palmitate on hepatic PPARγ transactivation and underlying mechanisms, as well as the role of PPARγ transactivation in palmitate-induced hepatic lipotoxicity, all of which remain ambiguous currently. Our data revealed that palmitate exposure was concomitant with both PPARγ transactivation and upregulation of nicotinamide N-methyltransferase (NNMT), a methyltransferase catalyzing the degradation of nicotinamide, the predominant precursor for cellular NAD+ biosynthesis. Importantly, we discovered that PPARγ transactivation by palmitate was blunted by NNMT inhibition, suggesting that NNMT upregulation plays a mechanistic role in PPARγ transactivation. Further investigations uncovered that palmitate exposure is associated with intracellular NAD+ decline and NAD+ replenishment with NAD+-enhancing agents, nicotinamide and nicotinamide riboside, obstructed palmitate-induced PPARγ transactivation, implying that cellular NAD+ decline resulted from NNMT upregulation represents a potential mechanism behind palmitate-elicited PPARγ transactivation. At last, our data showed that the PPARγ transactivation marginally ameliorated palmitate-induced intracellular triacylglycerol accumulation and cell death. Collectively, our data provided the first-line evidence supporting that NNMT upregulation plays a mechanistic role in palmitate-elicited PPARγ transactivation, potentially through reducing cellular NAD+ contents.NEW & NOTEWORTHY Hepatic PPARγ transactivation contributes to fatty liver development. Saturated fatty acids (SFAs) induce hepatic lipotoxicity. Here, we investigated whether and how palmitate, the most abundant SFA in the human blood, affects PPARγ transactivation in hepatocytes. We reported for the first time that upregulation of nicotinamide N-methyltransferase (NNMT), a methyltransferase catalyzing the degradation of nicotinamide, the predominant precursor for cellular NAD+ biosynthesis, plays a mechanistic role in regulating palmitate-elicited PPARγ transactivation through reducing intracellular NAD+ contents.


Assuntos
Fígado Gorduroso , Palmitatos , Camundongos , Animais , Humanos , Palmitatos/toxicidade , Nicotinamida N-Metiltransferase/genética , Nicotinamida N-Metiltransferase/metabolismo , Regulação para Cima , NAD/metabolismo , Ativação Transcricional , PPAR gama/genética , PPAR gama/metabolismo , Hepatócitos/metabolismo , Niacinamida/metabolismo , Niacinamida/farmacologia , Ácidos Graxos/metabolismo
13.
Clin Infect Dis ; 76(3): e1-e9, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36124697

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination has decreasing protection from acquiring any infection with emergence of new variants; however, vaccination continues to protect against progression to severe coronavirus disease 2019 (COVID-19). The impact of vaccination status on symptoms over time is less clear. METHODS: Within a randomized trial on early outpatient COVID-19 therapy testing metformin, ivermectin, and/or fluvoxamine, participants recorded symptoms daily for 14 days. Participants were given a paper symptom diary allowing them to circle the severity of 14 symptoms as none (0), mild (1), moderate (2), or severe (3). This is a secondary analysis of clinical trial data on symptom severity over time using generalized estimating equations comparing those unvaccinated, SARS-CoV-2 vaccinated with primary vaccine series only, or vaccine-boosted. RESULTS: The parent clinical trial prospectively enrolled 1323 participants, of whom 1062 (80%) prospectively recorded some daily symptom data. Of these, 480 (45%) were unvaccinated, 530 (50%) were vaccinated with primary series only, and 52 (5%) vaccine-boosted. Overall symptom severity was least for the vaccine-boosted group and most severe for unvaccinated at baseline and over the 14 days (P < .001). Individual symptoms were least severe in the vaccine-boosted group including cough, chills, fever, nausea, fatigue, myalgia, headache, and diarrhea, as well as smell and taste abnormalities. Results were consistent over Delta and Omicron variant time periods. CONCLUSIONS: SARS-CoV-2 vaccine-boosted participants had the least severe symptoms during COVID-19, which abated the quickest over time. Clinical Trial Registration. NCT04510194.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Vacinação
14.
J Hepatol ; 79(2): 314-320, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37088312

RESUMO

BACKGROUND & AIMS: The combination of sofosbuvir, velpatasvir and voxilaprevir (SOF/VEL/VOX) is recommended for the retreatment of patients with HCV infection in whom previous direct-acting antiviral (DAA) treatment failed. However, whether ribavirin further increases the therapeutic efficacy of SOF/VEL/VOX retreatment remains unclear. We aimed to test this hypothesis in a randomized-controlled trial. METHODS: We randomly assigned 315 patients with DAA treatment failure from five Egyptian sites into two groups. Group A (n = 158) received SOF/VEL/VOX for 12 weeks, and group B (n = 157) received SOF/VEL/VOX + weight-based ribavirin for 12 weeks. Therapeutic efficacy was defined as SVR12 (sustained virologic response 12 weeks after treatment end). Safety and tolerability were evaluated by monitoring treatment-related adverse events (AEs) and laboratory abnormalities. RESULTS: Males comprised 53.9% of group A and 57.1% of group B (p = 0.58); mean ages were 51.8 and 47.3 years in group A and B, respectively. Seventeen patients in each group were lost to follow-up. SVR12 rates were 87.3% (138/158) by intention-to-treat analysis and 97.8% (138/141) by per-protocol analysis in group A; and 87.9% (138/157) and 98.5% (138/140), respectively, in group B (p = n.s. for intention-to-treat and per-protocol analyses). Both regimens were well-tolerated, with no deaths and only one serious AE (anemia) in group B, which required ribavirin discontinuation. Fifty-five patients in group A vs. 77 in group B experienced any AE (p = 0.002). CONCLUSION: This randomized-controlled trial showed equal, high efficacy of both regimens for the retreatment of previous DAA failures, although ribavirin was associated with more AEs. Therefore SOF/VEL/VOX monotherapy should be the preferred retreatment strategy. CLINCIALTRIALS. GOV NUMBER: NCT04695769. IMPACT AND IMPLICATIONS: HCV treatment guidelines recommend retreatment of direct-acting antiviral (DAA) treatment failures with the combination of sofosbuvir, velpatasvir and voxilaprevir (SOF/VEL/VOX) for 12 weeks. However, whether ribavirin exerts an additional/synergistic effect remains unclear. The present study confirmed that SOF/VEL/VOX without ribavirin is the best regimen for retreatment of DAA treatment failures, and thus will help guide clinicians caring for patients who are not cured with a first course of DAA therapy.


Assuntos
Hepatite C Crônica , Hepatite C , Masculino , Humanos , Feminino , Sofosbuvir/efeitos adversos , Antivirais/efeitos adversos , Hepatite C Crônica/tratamento farmacológico , Ribavirina/efeitos adversos , Resultado do Tratamento , Quimioterapia Combinada , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Retratamento , Genótipo
15.
Am J Physiol Gastrointest Liver Physiol ; 324(5): G341-G353, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36852918

RESUMO

Hepatic lipotoxicity plays a central role in the pathogenesis of nonalcoholic fatty liver disease; however, the underlying mechanisms remain elusive. Here, using both cultured hepatocytes (AML-12 cells and primary mouse hepatocytes) and the liver-specific gene knockout mice, we investigated the mechanisms underlying palmitate-elicited upregulation of CD36, a class B scavenger receptor mediating long-chain fatty acids uptake, and its role in palmitate-induced hepatolipotoxicity. We found that palmitate upregulates hepatic CD36 expression. Despite being a well-established target gene of PPARγ transactivation, our data demonstrated that the palmitate-induced CD36 upregulation in hepatocytes is in fact PPARγ-independent. We previously reported that the activation of ATF4, one of three canonical pathways activated upon endoplasmic reticulum (ER) stress induction, contributes to palmitate-triggered lipotoxicity in hepatocytes. In this study, our data revealed for the first time that ATF4 plays a critical role in mediating hepatic CD36 expression. Genetic inhibition of ATF4 attenuated CD36 upregulation induced by either palmitate or ER stress inducer tunicamycin in hepatocytes. In mice, tunicamycin upregulates liver CD36 expression, whereas hepatocyte-specific ATF4 knockout mice manifest lower hepatic CD36 expression when compared with control animals. Furthermore, we demonstrated that CD36 upregulation upon palmitate exposure represents a feedforward mechanism in that siRNA knockdown of CD36 in hepatocytes blunted ATF4 activation induced by both palmitate and tunicamycin. Finally, we confirmed that the ATF4-CD36 pathway activation contributes to palmitate-induced hepatolipotoxicity as genetic inhibition of either ATF4 or CD36 alleviated cell death and intracellular triacylglycerol accumulation. Collectively, our data demonstrate that CD36 upregulation by ATF4 activation contributes to palmitate-induced hepatic lipotoxicity.NEW & NOTEWORTHY We provided the initial evidence that ATF4 is a principal transcription factor mediating hepatic CD36 expression in that both palmitate- and ER stress-elicited CD36 upregulation was blunted by ATF4 gene knockdown in hepatocytes, and hepatocyte-specific ATF4 knockout mice manifested lower hepatic CD36 expression. We further confirmed that the ATF4-CD36 pathway activation contributes to palmitate-induced hepatolipotoxicity as genetic inhibition of either ATF4 or CD36 alleviated cell death and intracellular triacylglycerol accumulation in response to exogenous palmitate exposure.


Assuntos
PPAR gama , Palmitatos , Animais , Camundongos , Palmitatos/toxicidade , Palmitatos/metabolismo , Regulação para Cima , Ativação Transcricional , PPAR gama/metabolismo , Tunicamicina/metabolismo , Hepatócitos/metabolismo , Estresse do Retículo Endoplasmático , Camundongos Knockout , Triglicerídeos/metabolismo
16.
Ophthalmology ; 130(7): 702-714, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36889466

RESUMO

TOPIC: Understanding approaches to sustainability in cataract surgery and their risks and benefits. CLINICAL RELEVANCE: In the United States, health care is responsible for approximately 8.5% of greenhouse gas (GHG), and cataract surgery is one of the most commonly performed surgical procedures. Ophthalmologists can contribute to reducing GHG emissions, which lead to a steadily increasing list of health concerns ranging from trauma to food instability. METHODS: We conducted a literature review to identify the benefits and risks of sustainability interventions. We then organized these interventions into a decision tree for use by individual surgeons. RESULTS: Identified sustainability interventions fall into the domains of advocacy and education, pharmaceuticals, process, and supplies and waste. Existing literature shows certain interventions may be safe, cost-effective, and environmentally friendly. These include dispensing medications at home to patients after surgery, multi-dosing appropriate medications, training staff to properly sort medical waste, reducing the number of supplies used during surgery, and implementing immediate sequential bilateral cataract surgery where clinically appropriate. The literature was lacking on the benefits or risks for some interventions, such as switching specific single-use supplies to reusables or implementing a hub-and-spoke-style operating room setup. Many of the advocacy and education interventions have inadequate literature specific to ophthalmology but are likely to have minimal risks. CONCLUSIONS: Ophthalmologists can engage in a variety of safe and effective approaches to reduce or eliminate dangerous GHG emissions associated with cataract surgery. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.


Assuntos
Extração de Catarata , Catarata , Cristalino , Oftalmologistas , Oftalmologia , Humanos
17.
Blood ; 138(4): 304-317, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-33786586

RESUMO

Hematopoiesis is extrinsically controlled by cells of the bone marrow microenvironment, including skeletal lineage cells. The identification and subsequent studies of distinct subpopulations of maturing skeletal cells is currently limited because of a lack of methods to isolate these cells. We found that murine Lin-CD31-Sca-1-CD51+ cells can be divided into 4 subpopulations by using flow cytometry based on their expression of the platelet-derived growth factor receptors ⍺ and ß (PDGFR⍺ and PDGFRß). The use of different skeletal lineage reporters confirmed the skeletal origin of the 4 populations. Multiplex immunohistochemistry studies revealed that all 4 populations were localized near the growth plate and trabecular bone and were rarely found near cortical bone regions or in central bone marrow. Functional studies revealed differences in their abundance, colony-forming unit-fibroblast capacity, and potential to differentiate into mineralized osteoblasts or adipocytes in vitro. Furthermore, the 4 populations had distinct gene expression profiles and differential cell surface expression of leptin receptor (LEPR) and vascular cell adhesion molecule 1 (VCAM-1). Interestingly, we discovered that 1 of these 4 different skeletal populations showed the highest expression of genes involved in the extrinsic regulation of B lymphopoiesis. This cell population varied in abundance between distinct hematopoietically active skeletal sites, and significant differences in the proportions of B-lymphocyte precursors were also observed in these distinct skeletal sites. This cell population also supported pre-B lymphopoiesis in culture. Our method of isolating 4 distinct maturing skeletal populations will help elucidate the roles of distinct skeletal niche cells in regulating hematopoiesis and bone.


Assuntos
Linfócitos B/imunologia , Diferenciação Celular/imunologia , Linfopoese/imunologia , Músculo Esquelético/imunologia , Animais , Diferenciação Celular/genética , Linfopoese/genética , Camundongos , Camundongos Transgênicos
18.
Liver Int ; 43(4): 805-818, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36606706

RESUMO

BACKGROUND: Direct-acting antiviral agents (DAAs) have transformed chronic hepatitis C (CHC) treatment. Continued affordable access to DAAs requires updated cost-effectiveness analyses (CEA). Utility is a preference-based measure of health-related quality of life (HRQoL) used in CEA. This study evaluated the impact of DAAs on utilities for patients with CHC in two clinical settings. METHODS: This prospective longitudinal study included patients aged ≥18 years, diagnosed with CHC and scheduled to begin DAA treatment, from two tertiary care hospital clinics and four community clinics in Toronto, Calgary, and Montreal. Patients completed two utility instruments (EQ-5D-5L and Health Utilities Index 2/3 (HUI2/3)) before treatment, 6 weeks after treatment initiation, and 12 weeks and 1 year after treatment completion. We measured utilities for all patients, and for hospital-based and community-based groups. RESULTS: Between 2017 and 2020, 209 patients (126 hospital-based, 83 community-based; average age 53 years; 65% male) were recruited, and 143 completed the 1-year post-treatment assessment. Pre-treatment, utilities were (mean ± standard deviation) 0.77 ± 0.21 (EQ-5D-5L), 0.69 ± 0.24 (HUI2) and 0.58 ± 0.34 (HUI3). The mean changes at 1-year post-treatment were 0.035, 0.038 and 0.071, respectively. While utilities for hospital-based patients steadily improved, utilities for the community-based cohort improved between baseline and 12-weeks post-treatment, but decreased thereafter. DISCUSSION: This study suggests that utilities improve after DAA treatment in patients with CHC in a variety of settings. However, community-based patients may face challenges related to comorbid health and social conditions that are not meaningfully addressed by treatment. Our study is essential for valuing health outcomes in CHC-related CEA.


Assuntos
Antivirais , Hepatite C Crônica , Humanos , Masculino , Adolescente , Adulto , Pessoa de Meia-Idade , Feminino , Antivirais/uso terapêutico , Qualidade de Vida , Hepatite C Crônica/tratamento farmacológico , Estudos Prospectivos , Estudos Longitudinais , Inquéritos e Questionários , Hospitais
19.
J Endovasc Ther ; : 15266028231204291, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853703

RESUMO

PURPOSE: Access-related vascular complications in transfemoral transcatheter aortic valve implantation (TAVI) can be treated endovascularly or surgically. The aim of this study was to evaluate the short- and long-term outcomes of endovascular treatment compared with surgical repair for access-related vascular complications. METHODS: This retrospective study was performed from January 1, 2018, to December 31, 2020. All transfemorally treated TAVI patients in whom a surgical or endovascular treatment for an access site complication was needed were included. The primary outcome was the need for any related vascular re-operation. RESULTS: In total, 1219 transfemoral TAVI procedures were conducted during the study period. 19 patients suffered an access complication requiring endovascular treatment, while 54 patients required surgical repair. No differences were seen with regard to re-operations (endovascular 15.8% vs surgical 14.8%; p=0.919), wound infections (endovascular 0% vs surgical. 11.1%; p=0.129), and wound healing disorders (endovascular 15.8% vs surgical 29.6%; p=0.237). Patients undergoing endovascular treatment were discharged earlier (endovascular 11.2 vs surgical 14.9 days; p=0.028). After surgical repair, patients received significantly more blood transfusions than endovascularly treated patients (endovascular 1.00 vs surgical 3.1 red blood cell concentrate bags; p<0.001). No differences were found regarding the new onset of walking pain, rest pain, and ischemic ulcers during follow-up. CONCLUSION: In this retrospective cohort, endovascular treatment of access-related vascular complications of transfemoral TAVI procedures was safe and feasible. During the hospital stay, endovascularly treated patients received fewer blood transfusions and were discharged faster than surgically treated patients. No differences regarding clinical outcomes and re-intervention rates were seen during the follow-up. CLINICAL IMPACT: Given the in this retrospective study demonstrated safety and feasibility of endovascular treatment for major access-related vascular complications, along with the in-hospital benefits and absence of follow-up disadvantages compared to surgical treatment, endovascular treatment should be considered in cases of major access-related vascular complications in transfemoral TAVI patients.

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