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1.
N Engl J Med ; 388(14): 1259-1271, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36762865

RESUMO

BACKGROUND: Trials of the efficacy and safety of endovascular thrombectomy in patients with large ischemic strokes have been carried out in limited populations. METHODS: We performed a prospective, randomized, open-label, adaptive, international trial involving patients with stroke due to occlusion of the internal carotid artery or the first segment of the middle cerebral artery to assess endovascular thrombectomy within 24 hours after onset. Patients had a large ischemic-core volume, defined as an Alberta Stroke Program Early Computed Tomography Score of 3 to 5 (range, 0 to 10, with lower scores indicating larger infarction) or a core volume of at least 50 ml on computed tomography perfusion or diffusion-weighted magnetic resonance imaging. Patients were assigned in a 1:1 ratio to endovascular thrombectomy plus medical care or to medical care alone. The primary outcome was the modified Rankin scale score at 90 days (range, 0 to 6, with higher scores indicating greater disability). Functional independence was a secondary outcome. RESULTS: The trial was stopped early for efficacy; 178 patients had been assigned to the thrombectomy group and 174 to the medical-care group. The generalized odds ratio for a shift in the distribution of modified Rankin scale scores toward better outcomes in favor of thrombectomy was 1.51 (95% confidence interval [CI], 1.20 to 1.89; P<0.001). A total of 20% of the patients in the thrombectomy group and 7% in the medical-care group had functional independence (relative risk, 2.97; 95% CI, 1.60 to 5.51). Mortality was similar in the two groups. In the thrombectomy group, arterial access-site complications occurred in 5 patients, dissection in 10, cerebral-vessel perforation in 7, and transient vasospasm in 11. Symptomatic intracranial hemorrhage occurred in 1 patient in the thrombectomy group and in 2 in the medical-care group. CONCLUSIONS: Among patients with large ischemic strokes, endovascular thrombectomy resulted in better functional outcomes than medical care but was associated with vascular complications. Cerebral hemorrhages were infrequent in both groups. (Funded by Stryker Neurovascular; SELECT2 ClinicalTrials.gov number, NCT03876457.).


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Trombectomia , Humanos , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/cirurgia , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Trombectomia/métodos , Resultado do Tratamento , Infarto da Artéria Cerebral Média/complicações , Doenças das Artérias Carótidas/complicações , Recuperação de Função Fisiológica , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/etiologia
2.
J Biol Chem ; 300(3): 105726, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325741

RESUMO

Hyperlipidemia predisposes individuals to cardiometabolic diseases, the most common cause of global mortality. Microsomal triglyceride transfer protein (MTP) transfers multiple lipids and is essential for the assembly of apolipoprotein B-containing lipoproteins. MTP inhibition lowers plasma lipids but causes lipid retention in the liver and intestine. Previous studies suggested two lipid transfer domains in MTP and that specific inhibition of triglyceride (TG) and not phospholipid (PL) transfer can lower plasma lipids without significant tissue lipid accumulation. However, how MTP transfers different lipids and the domains involved in these activities are unknown. Here, we tested a hypothesis that two different ß-sandwich domains in MTP transfer TG and PL. Mutagenesis of charged amino acids in ß2-sandwich had no effect on PL transfer activity indicating that they are not critical. In contrast, amino acids with bulky hydrophobic side chains in ß1-sandwich were critical for both TG and PL transfer activities. Substitutions of these residues with smaller hydrophobic side chains or positive charges reduced, whereas negatively charged side chains severely attenuated MTP lipid transfer activities. These studies point to a common lipid transfer domain for TG and PL in MTP that is enriched with bulky hydrophobic amino acids. Furthermore, we observed a strong correlation in different MTP mutants with respect to loss of both the lipid transfer activities, again implicating a common binding site for TG and PL in MTP. We propose that targeting of areas other than the identified common lipid transfer domain might reduce plasma lipids without causing cellular lipid retention.


Assuntos
Proteínas de Transporte , Interações Hidrofóbicas e Hidrofílicas , Fosfolipídeos , Triglicerídeos , Humanos , Aminoácidos/química , Aminoácidos/genética , Aminoácidos/metabolismo , Apolipoproteínas B/química , Apolipoproteínas B/metabolismo , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Fosfolipídeos/sangue , Fosfolipídeos/metabolismo , Triglicerídeos/sangue , Triglicerídeos/metabolismo , Domínios Proteicos , Mutação , Relação Estrutura-Atividade , Sítios de Ligação
3.
Ann Neurol ; 96(3): 582-590, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38922985

RESUMO

OBJECTIVES: The benefits of intravenous thrombolysis are time-dependent, with maximum efficacy when administered within the first "golden" hour after onset. Nevertheless, the impact of golden hour thrombolysis has not been well quantified. METHODS: Medline, Embase, and Web of Science databases were systematically searched from inception to August 27, 2023. We included studies that reported safety and efficacy outcomes of ischemic stroke patients treated with intravenous thrombolysis in the golden hour versus later treatment window. The primary outcome was an excellent functional outcome, defined as a modified Rankin Scale score of 0-1 at 90 days. The secondary efficacy outcome was a good functional outcome (defined as modified Rankin Scale score of 0-2). The main safety outcome was symptomatic intracerebral hemorrhage. RESULTS: Seven studies involving 78,826 patients met the selection criteria. Golden hour thrombolysis was associated with higher odds of 90-day excellent functional outcomes (OR 1.40, 95% CI 1.16-1.67) and 90-day good functional outcomes (OR 1.38, 95% CI 1.13-1.69) compared with thrombolysis outside the golden hour. The number needed to treat to benefit for golden hour thrombolysis to reduce disability by at least 1 level on the modified Rankin Scale per patient was 2.6. Rates of symptomatic intracerebral hemorrhage and mortality were similar between groups. INTERPRETATION: Golden hour thrombolysis significantly improved acute ischemic stroke outcomes. The findings provide rationale for intensive efforts aimed at expediting thrombolytic therapy within the golden hour window following the onset of acute ischemic stroke. ANN NEUROL 2024;96:582-590.


Assuntos
Fibrinolíticos , AVC Isquêmico , Terapia Trombolítica , Tempo para o Tratamento , Humanos , AVC Isquêmico/tratamento farmacológico , Terapia Trombolítica/métodos , Fibrinolíticos/uso terapêutico , Fibrinolíticos/administração & dosagem , Administração Intravenosa , Resultado do Tratamento , Fatores de Tempo
4.
Ann Neurol ; 2024 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039739

RESUMO

Endovascular thrombectomy (EVT) safety and efficacy in patients with large core infarcts receiving oral anticoagulants (OAC) are unknown. In the SELECT2 trial (NCT03876457), 29 of 180 (16%; vitamin K antagonists 15, direct OACs 14) EVT, and 18 of 172 (10%; vitamin K antagonists 3, direct OACs 15) medical management (MM) patients reported OAC use at baseline. EVT was not associated with better clinical outcomes in the OAC group (EVT 6 [4-6] vs MM 5 [4-6], adjusted generalized odds ratio 0.89 [0.53-1.50]), but demonstrated significantly better outcomes in patients without OAC (EVT 4 [3-6] vs MM 5 [4-6], adjusted generalized odds ratio 1.87 [1.45-2.40], p = 0.02). The OAC group had higher comorbidities, including atrial fibrillation (70% vs 17%), congestive heart failure (28% vs 10%), and hypertension (87% vs 72%), suggesting increased frailty. However, the results were consistent after adjustment for these comorbidities, and was similar regardless of the type of OACs used. Whereas any hemorrhage rates were higher in the OAC group receiving EVT (86% in OAC vs 70% in no OAC), no parenchymal hemorrhage or symptomatic intracranial hemorrhage were observed with OAC use in both the EVT and MM arms. Although we did not find evidence that the effect was due to excess hemorrhage or confounded by underlying cardiac disease or older age, OAC use alone should not exclude patients from receiving EVT. Baseline comorbidities and ischemic injury extent should be considered while making individualized treatment decisions. ANN NEUROL 2024.

5.
FASEB J ; 38(5): e23522, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38445789

RESUMO

Lipid processing by the retinal pigment epithelium (RPE) is necessary to maintain retinal health and function. Dysregulation of retinal lipid homeostasis due to normal aging or age-related disease triggers lipid accumulation within the RPE, on Bruch's membrane (BrM), and in the subretinal space. In its role as a hub for lipid trafficking into and out of the neural retina, the RPE packages a significant amount of lipid into lipid droplets for storage and into apolipoprotein B (APOB)-containing lipoproteins (Blps) for export. Microsomal triglyceride transfer protein (MTP), encoded by the MTTP gene, is essential for Blp assembly. Herein we test the hypothesis that MTP expression in the RPE is essential to maintain lipid balance and retinal function using the newly generated RPEΔMttp mouse model. Using non-invasive ocular imaging, electroretinography, and histochemical and biochemical analyses we show that genetic depletion of Mttp from the RPE results in intracellular lipid accumulation, increased photoreceptor-associated cholesterol deposits, and photoreceptor cell death, and loss of rod but not cone function. RPE-specific reduction in Mttp had no significant effect on plasma lipids and lipoproteins. While APOB was decreased in the RPE, most ocular retinoids remained unchanged, with the exception of the storage form of retinoid, retinyl ester. Thus suggesting that RPE MTP is critical for Blp synthesis and assembly but is not directly involved in plasma lipoprotein metabolism. These studies demonstrate that RPE-specific MTP expression is necessary to establish and maintain retinal lipid homeostasis and visual function.


Assuntos
Proteínas de Transporte , Retina , Epitélio Pigmentado da Retina , Animais , Camundongos , Retinoides , Apolipoproteínas B/genética , Homeostase
6.
J Lipid Res ; : 100659, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39332527

RESUMO

Plasma lipids are mainly carried in apolipoprotein B (apoB) containing lipoproteins. High levels of these lipoproteins are associated with several metabolic diseases and lowering their plasma levels are associated with reduced incidence of atherosclerotic cardiovascular disease. MicroRNAs (miRs) are small non-coding RNAs that reduce protein expression of their target mRNAs and are potential therapeutic agents. Here, we identified a novel miR-615-3p that interacts with human 3'-UTR of apoB mRNA, induces post-transcriptional mRNA degradation, and reduces cellular and secreted apoB100 in human hepatoma Huh-7 cells. Reducing cellular miR-615-3p levels by CRISPR-sgRNA increased cellular and secreted apoB100 indicating endogenous miR regulates apoB expression. Overexpression of miR-615-3p along with or without palmitic acid treatment decreased cellular and media apoB and increased cellular triglyceride levels without inducing endoplasmic reticulum stress. These studies have identified miR-615-3p as a negative regulator of apoB expression in human liver derived cells. It is likely that there are more miRs that regulate apoB-containing lipoprotein assembly and secretion. Discovery of additional miRs may uncover novel mechanisms that control lipoprotein assembly and secretion.

7.
Hepatology ; 78(5): 1418-1432, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36053190

RESUMO

BACKGROUND AND AIMS: The assembly and secretion of VLDL from the liver, a pathway that affects hepatic and plasma lipids, remains incompletely understood. We set out to identify players in the VLDL biogenesis pathway by identifying genes that are co-expressed with the MTTP gene that encodes for microsomal triglyceride transfer protein, key to the lipidation of apolipoprotein B, the core protein of VLDL. Using human and murine transcriptomic data sets, we identified small leucine-rich protein 1 ( SMLR1 ), encoding for small leucine-rich protein 1, a protein of unknown function that is exclusively expressed in liver and small intestine. APPROACH AND RESULTS: To assess the role of SMLR1 in the liver, we used somatic CRISPR/CRISPR-associated protein 9 gene editing to silence murine Smlr1 in hepatocytes ( Smlr1 -LKO). When fed a chow diet, male and female mice show hepatic steatosis, reduced plasma apolipoprotein B and triglycerides, and reduced VLDL secretion without affecting microsomal triglyceride transfer protein activity. Immunofluorescence studies show that SMLR1 is in the endoplasmic reticulum and Cis-Golgi complex. The loss of hepatic SMLR1 in female mice protects against diet-induced hyperlipidemia and atherosclerosis but causes NASH. On a high-fat, high-cholesterol diet, insulin and glucose tolerance tests did not reveal differences in male Smlr1 -LKO mice versus controls. CONCLUSIONS: We propose a role for SMLR1 in the trafficking of VLDL from the endoplasmic reticulum to the Cis-Golgi complex. While this study uncovers SMLR1 as a player in the VLDL assembly, trafficking, and secretion pathway, it also shows that NASH can occur with undisturbed glucose homeostasis and atheroprotection.


Assuntos
Aterosclerose , Lipoproteínas VLDL , Hepatopatia Gordurosa não Alcoólica , Proteoglicanos Pequenos Ricos em Leucina , Animais , Feminino , Humanos , Masculino , Camundongos , Apolipoproteínas B/sangue , Aterosclerose/sangue , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/prevenção & controle , Leucina , Lipoproteínas VLDL/biossíntese , Lipoproteínas VLDL/sangue , Lipoproteínas VLDL/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteoglicanos Pequenos Ricos em Leucina/genética , Proteoglicanos Pequenos Ricos em Leucina/metabolismo , Triglicerídeos/sangue
8.
Ann Neurol ; 93(4): 793-804, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36571388

RESUMO

OBJECTIVE: Reperfusion therapy is highly beneficial for ischemic stroke. Reduction in both infarct growth and edema are plausible mediators of clinical benefit with reperfusion. We aimed to quantify these mediators and their interrelationship. METHODS: In a pooled, patient-level analysis of the EXTEND-IA trials and SELECT study, we used a mediation analysis framework to quantify infarct growth and cerebral edema (midline shift) mediation effect on successful reperfusion (modified Treatment in Cerebral Ischemia ≥ 2b) association with functional outcome (modified Rankin Scale distribution). Furthermore, we evaluated an additional pathway to the original hypothesis, where infarct growth mediated successful reperfusion effect on midline shift. RESULTS: A total 542 of 665 (81.5%) eligible patients achieved successful reperfusion. Baseline clinical and imaging characteristics were largely similar between those achieving successful versus unsuccessful reperfusion. Median infarct growth was 12.3ml (interquartile range [IQR] = 1.8-48.4), and median midline shift was 0mm (IQR = 0-2.2). Of 249 (37%) demonstrating a midline shift of ≥1mm, median shift was 2.75mm (IQR = 1.89-4.21). Successful reperfusion was associated with reductions in both predefined mediators, infarct growth (ß = -1.19, 95% confidence interval [CI] = -1.51 to -0.88, p < 0.001) and midline shift (adjusted odds ratio = 0.36, 95% CI = 0.23-0.57, p < 0.001). Successful reperfusion association with improved functional outcome (adjusted common odds ratio [acOR] = 2.68, 95% CI = 1.86-3.88, p < 0.001) became insignificant (acOR = 1.39, 95% CI = 0.95-2.04, p = 0.094) when infarct growth and midline shift were added to the regression model. Infarct growth and midline shift explained 45% and 34% of successful reperfusion effect, respectively. Analysis considering an alternative hypothesis demonstrated consistent results. INTERPRETATION: In this mediation analysis from a pooled, patient-level cohort, a significant proportion (~80%) of successful reperfusion effect on functional outcome was mediated through reduction in infarct growth and cerebral edema. Further studies are required to confirm our findings, detect additional mediators to explain successful reperfusion residual effect, and identify novel therapeutic targets to further enhance reperfusion benefits. ANN NEUROL 2023;93:793-804.


Assuntos
Edema Encefálico , Isquemia Encefálica , Procedimentos Endovasculares , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/complicações , Edema Encefálico/etiologia , Edema Encefálico/complicações , Resultado do Tratamento , Estudos Prospectivos , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia , Isquemia Encefálica/complicações , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/terapia , Infarto Cerebral/complicações , Reperfusão/métodos , Procedimentos Endovasculares/métodos
9.
Aging Clin Exp Res ; 36(1): 162, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110364

RESUMO

OBJECTIVES: A low handgrip strength (HGS) is a significant risk factor for multiple diseases. However, most relevant studies investigate the complications of a low HGS, while the risk potential of causative factors of low HGS remain poorly characterized. METHODS: We investigated the potentials of quality of life, depression, dyslipidaemia, diabetes mellitus, cancer, Alzheimer's disease, stroke, frailty, and difficulties performing daily activities in predicting low HGS (≤ 27 kg for men, ≤ 16 kg for women) in European older adults aged 50 or above from 15 countries (n = 42,183). All data was collected from four successive waves of survey of health, ageing, and retirement in Europe (SHARE) conducted between 2013 and 2020. Logistic models are applied, and estimated effects are presented as odds ratios and probabilities. RESULTS: Collectively, 3016 participants (men; n = 1395; 7.38%, women; n = 1621, 6.97%) developed low HGS during the 6.5 years study period. After adjusting for covariables, we identified an advancing age (1.6-48.1% points higher risk of low HGS), male gender (1.0%-point higher risk of low HGS), lower quality of life (1.6%-point higher), and stroke (1.5%-points) as significant risk factors for low HGS. We also found a dose-dependent association of Euro-D depression scores with the risk of low HGS, as the higher scores were associated with between 0.6- and 2.3%-points higher risk of developing low HGS than participants without depression. Among physical performance indicators, difficulty climbing stairs (2.0%-points higher low HGS risk) or rising from a chair (0.7%-points) were significantly associated with developing low HGS. Lastly, frailty (0.9%-points higher risk of low HGS) and the fear of falling down (1.6%-points higher risk) also increased the risk of developing low HGS. CONCLUSION: Altogether, we report several risk factors for developing low HGS. Our observations may help evaluating and monitoring high-risk population for developing low HGS in pre-clinical settings.


Assuntos
Força da Mão , Qualidade de Vida , Humanos , Masculino , Feminino , Idoso , Força da Mão/fisiologia , Europa (Continente)/epidemiologia , Estudos Longitudinais , Pessoa de Meia-Idade , Fatores de Risco , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Atividades Cotidianas , Fragilidade/epidemiologia
10.
J Stroke Cerebrovasc Dis ; 33(12): 108027, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39307210

RESUMO

INTRODUCTION: Large vessel occlusion-acute ischemic stroke (LVO-AIS) is infrequent in young adults and exhibits distinct stroke mechanisms compared to older adults. This study sought to evaluate the impact of varying stroke etiologies on treatment-related outcomes in young adults with LVO-AIS, an aspect that remains unclear. METHODS: This retrospective cohort study included patients aged 18-50 presenting with AIS from January 2017 to December 2021 within our multi-center stroke network. Patients with LVO on CTA/MRA at presentation were included. We assessed demographics, stroke etiology (TOAST classification), and treatment-related outcomes. Based on intervention received, patients were divided into 5 groups [IV-thrombolysis (IVT) only, Mechanical Thrombectomy (MT) only, IVT+MT, no treatment, unsuccessful MT]. RESULTS: Among 1210 AIS patients, 220 with LVO were included. The median age was 42 (36, 46). 75 (34.1 %) patients underwent successful MT (46.7 % received IVT+MT). 26 (11.8 %) received IVT only, 110 (50 %) received neither intervention, and 9 (4.1 %) underwent unsuccessful MT. Per TOAST, 17.4 % had large artery atherosclerosis (LAA), 19.2 % cardio-embolism, 28.6 % stroke of other etiology, and 34.7 % had undetermined etiology. Favorable thrombectomy outcomes (TICI 2b/2c/3) were observed in 87.2 %. Discharge NIH Stroke Scale (NIHSS) scores improved for patients with IVT+MT in all TOAST categories except LAA. CONCLUSIONS: Young adults with LVO-AIS had good outcomes irrespective of stroke etiology, except LAA, which was associated with a higher discharge NIHSS. Moreover, 50 % of young adults in our study received no intervention, a quarter of those owing to delayed presentation. Further studies are needed to identify barriers in seeking acute treatment in young adults with LVO-AIS.

11.
J Environ Manage ; 366: 121816, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39029168

RESUMO

Unlike previous studies that have examined the association between different economic development parameters and environmental sustainability, the present study utilised an index of productive capacity to offer an in-depth understanding of the ecological impact of improving a nation's productive resources. It also emphasised the importance of remittances in reducing environmental degradation in uncertain economic and political environments. This study applied the system GMM technique and an advanced panel quantile regression technique to 36 Sub-Saharan Africa (SSA) region countries from 2000 to 2022. The findings showed that improvements in productive capacity might exert pressure on environmental quality, uncertainty, and the inflow of remittances, which tended to have a positive effect, ultimately leading to better environmental outcomes. Furthermore, the study indicated that these variables' impacts differed depending on each country's prevailing ecological conditions. It is, therefore, vital that efforts to achieve sustainable development in the SSA region consider the combined impact of these factors on environmental quality.


Assuntos
Conservação dos Recursos Naturais , África Subsaariana , Incerteza , Desenvolvimento Sustentável , Desenvolvimento Econômico
12.
Trop Anim Health Prod ; 56(8): 328, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373945

RESUMO

Ovine herpesvirus-2 (OvHV-2) is the causative agent of malignant catarrhal fever (MCF), a serious and often fatal disease that affects cattle and other ruminants. This study aimed to investigate the molecular epidemiology and genetic diversity of OvHV-2 strains circulating in sheep and cattle populations in the Jammu and Kashmir region of India. Screening of 150 sheep and 57 cattle blood samples revealed the presence of the OvHV-2 polymerase (pol) gene in 8.6% of sheep, 10% of apparently healthy cattle, and 29.7% of cattle exhibiting MCF-like symptoms. The full-length glycoprotein B (gB) gene (2800 bp) and an 875 bp internal fragment were successfully amplified, cloned, and sequenced from pol-positive samples. Comparative sequence analysis of the deduced gB amino acid sequences identified seven substitutions at positions 278, 341, 390, 440, 468, 539, and 566 compared to reference strains. Phylogenetic analysis based on the gB nucleotide sequences clustered the OvHV-2 strains from this study within the Indian clade, distinct from strains reported in the UK and US. These findings provide insights into the genetic diversity of OvHV-2 strains circulating in Jammu and Kashmir, with the identified mutations potentially influencing virus-host interactions. Further investigations into the functional implications of these mutations are warranted to understand their role in viral pathogenesis and tropism.


Assuntos
Variação Genética , Filogenia , Doenças dos Ovinos , Animais , Bovinos , Ovinos , Índia/epidemiologia , Doenças dos Ovinos/virologia , Doenças dos Ovinos/epidemiologia , Doenças dos Bovinos/virologia , Doenças dos Bovinos/epidemiologia , Gammaherpesvirinae/genética , Gammaherpesvirinae/isolamento & purificação , Gammaherpesvirinae/classificação , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Infecções por Herpesviridae/epidemiologia , Febre Catarral Maligna/virologia , Febre Catarral Maligna/epidemiologia , Doenças Assintomáticas , Análise de Sequência de DNA/veterinária , Epidemiologia Molecular , DNA Viral/genética
13.
J Biol Chem ; 298(4): 101813, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35278429

RESUMO

High plasma lipid levels have been demonstrated to increase cardiovascular disease risk. Despite advances in treatments to decrease plasma lipids, additional therapeutics are still needed because many people are intolerant or nonresponsive to these therapies. We previously showed that increasing cellular levels of microRNA-30c (miR-30c) using viral vectors or liposomes reduces plasma lipids and atherosclerosis. In this study, we aimed to synthesize potent miR-30c analogs that can be delivered to hepatoma cells without the aid of viral vectors and lipid emulsions. We hypothesized that modification of the passenger strand of miR-30c would increase the stability of miR-30c and augment its delivery to liver cells. Here, we report the successful synthesis of a series of miR-30c analogs by using different chemically modified nucleosides. In these analogs, we left the active sense strand untouched so that its biological activity remained unaltered, and we modified the passenger strand of miR-30c to enhance the stability and uptake of miR-30c by hepatoma cells through phosphorothiorate linkages and the addition of GalNAc. We show that these analogs significantly reduced apolipoprotein B secretion in Huh-7 human hepatoma cells and human primary hepatocytes without affecting apolipoprotein A1 secretion and cellular lipid levels. Our results provide a proof of concept that the passenger strand of miR-30c can be modified to increase its stability and delivery to cells while retaining the potency of the sense strand. We anticipate these miR-30c analogs will be useful in the development of more efficacious analogs for the treatment of hyperlipidemias and cardiovascular diseases.


Assuntos
Apolipoproteínas B , Carcinoma Hepatocelular , Hepatócitos , Neoplasias Hepáticas , Apolipoproteínas B/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , MicroRNAs/farmacologia
14.
J Biol Chem ; 298(3): 101685, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35131264

RESUMO

Most mammalian phospholipids contain a saturated fatty acid at the sn-1 carbon atom and an unsaturated fatty acid at the sn-2 carbon atom of the glycerol backbone group. While the sn-2 linked chains undergo extensive remodeling by deacylation and reacylation (Lands cycle), it is not known how the composition of saturated fatty acids is controlled at the sn-1 position. Here, we demonstrate that lysophosphatidylglycerol acyltransferase 1 (LPGAT1) is an sn-1 specific acyltransferase that controls the stearate/palmitate ratio of phosphatidylethanolamine (PE) and phosphatidylcholine. Bacterially expressed murine LPGAT1 transferred saturated acyl-CoAs specifically into the sn-1 position of lysophosphatidylethanolamine (LPE) rather than lysophosphatidylglycerol and preferred stearoyl-CoA over palmitoyl-CoA as the substrate. In addition, genetic ablation of LPGAT1 in mice abolished 1-LPE:stearoyl-CoA acyltransferase activity and caused a shift from stearate to palmitate species in PE, dimethyl-PE, and phosphatidylcholine. Lysophosphatidylglycerol acyltransferase 1 KO mice were leaner and had a shorter life span than their littermate controls. Finally, we show that total lipid synthesis was reduced in isolated hepatocytes of LPGAT1 knockout mice. Thus, we conclude that LPGAT1 is an sn-1 specific LPE acyltransferase that controls the stearate/palmitate homeostasis of PE and the metabolites of the PE methylation pathway and that LPGAT1 plays a central role in the regulation of lipid biosynthesis with implications for body fat content and longevity.


Assuntos
Aciltransferases , Palmitatos , Fosfatidilcolinas , Estearatos , Aciltransferases/metabolismo , Animais , Carbono , Ácidos Graxos , Mamíferos/metabolismo , Camundongos , Camundongos Knockout , Palmitatos/metabolismo , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas , Estearatos/metabolismo
15.
J Biol Chem ; 298(10): 102411, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36007616

RESUMO

Sphingomyelin (SM) is an abundant plasma membrane and plasma lipoprotein sphingolipid. We previously reported that ATP-binding cassette family A protein 1 (ABCA1) deficiency in humans and mice decreases plasma SM levels. However, overexpression, induction, downregulation, inhibition, and knockdown of ABCA1 in human hepatoma Huh7 cells did not decrease SM efflux. Using unbiased siRNA screening, here, we identified that ABCA7 plays a role in the biosynthesis and efflux of SM without affecting cellular uptake and metabolism. Since loss of function mutations in the ABCA7 gene exhibit strong associations with late-onset Alzheimer's disease across racial groups, we also studied the effects of ABCA7 deficiency in the mouse brain. Brains of ABCA7-deficient (KO) mice, compared with WT, had significantly lower levels of several SM species with long chain fatty acids. In addition, we observed that older KO mice exhibited behavioral deficits in cognitive discrimination in the active place avoidance task. Next, we performed synaptic transmission studies in brain slices obtained from older mice. We found anomalies in synaptic plasticity at the intracortical synapse in layer II/III of the lateral entorhinal cortex but not in the hippocampal CA3-CA1 synapses in KO mice. These synaptic abnormalities in KO brain slices were rescued with extracellular SM supplementation but not by supplementation with phosphatidylcholine. Taken together, these studies identify a role of ABCA7 in brain SM metabolism and the importance of SM in synaptic plasticity and cognition, as well as provide a possible explanation for the association between ABCA7 and late-onset Alzheimer's disease.


Assuntos
Doença de Alzheimer , Cognição , Córtex Entorrinal , Plasticidade Neuronal , Esfingomielinas , Animais , Humanos , Camundongos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Córtex Entorrinal/metabolismo , Esfingomielinas/biossíntese , Camundongos Knockout
16.
Cancer Immunol Immunother ; 72(12): 4221-4234, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37940720

RESUMO

Renal cell carcinoma is an immunogenic tumour with a prominent dysfunctional immune cell infiltrate, unable to control tumour growth. Although tyrosine kinase inhibitors and immunotherapy have improved the outlook for some patients, many individuals are non-responders or relapse despite treatment. The hostile metabolic environment in RCC affects the ability of T-cells to maintain their own metabolic programme constraining T-cell immunity in RCC. We investigated the phenotype, function and metabolic capability of RCC TILs correlating this with clinicopathological features of the tumour and metabolic environment at the different disease stages. Flow cytometric analysis of freshly isolated TILs showed the emergence of exhausted T-cells in advanced disease based on their PD-1high and CD39 expression and reduced production of inflammatory cytokines upon in vitro stimulation. Exhausted T-cells from advanced stage disease also displayed an overall phenotype of metabolic insufficiency, characterized by mitochondrial alterations and defects in glucose uptake. Nanostring nCounter cancer metabolism assay on RNA obtained from 30 ccRCC cases revealed significant over-expression of metabolic genes even at early stage disease (pT1-2), while at pT3-4 and the locally advanced thrombi stages, there was an overall decrease in differentially expressed metabolic genes. Notably, the gene PPARGC1A was the most significantly down-regulated gene from pT1-2 to pT3-4 RCC which correlated with loss of mitochondrial function in tumour-infiltrating T-cells evident at this tumour stage. Down-regulation of PPARGC1A into stage pT3-4 may be the 'tipping-point' in RCC disease progression, modulating immune activity in ccRCC and potentially reducing the efficacy of immunotherapies in RCC and poorer patient outcomes.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Recidiva Local de Neoplasia , Progressão da Doença , Imunidade
17.
Hepatology ; 76(1): 78-93, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34626126

RESUMO

BACKGROUND AND AIMS: High plasma lipid/lipoprotein levels are risk factors for various metabolic diseases. We previously showed that circadian rhythms regulate plasma lipids and deregulation of these rhythms causes hyperlipidemia and atherosclerosis in mice. Here, we show that global and liver-specific brain and muscle aryl hydrocarbon receptor nuclear translocator-like 1 (Bmal1)-deficient mice maintained on a chow or Western diet developed hyperlipidemia, denoted by the presence of higher amounts of triglyceride-rich and apolipoprotein AIV (ApoAIV)-rich larger chylomicron and VLDL due to overproduction. APPROACH AND RESULTS: Bmal1 deficiency decreased small heterodimer partner (Shp) and increased microsomal triglyceride transfer protein (MTP), a key protein that facilitates primordial lipoprotein assembly and secretion. Moreover, we show that Bmal1 regulates cAMP-responsive element-binding protein H (Crebh) to modulate ApoAIV expression and the assembly of larger lipoproteins. This is supported by the observation that Crebh-deficient and ApoAIV-deficient mice, along with Bmal1-deficient mice with knockdown of Crebh, had smaller lipoproteins. Further, overexpression of Bmal1 in Crebh-deficient mice had no effect on ApoAIV expression and lipoprotein size. CONCLUSIONS: These studies indicate that regulation of ApoAIV and assembly of larger lipoproteins by Bmal1 requires Crebh. Mechanistic studies showed that Bmal1 regulates Crebh expression by two mechanisms. First, Bmal1 interacts with the Crebh promoter to control circadian regulation. Second, Bmal1 increases Rev-erbα expression, and nuclear receptor subfamily 1 group D member 1 (Nr1D1, Rev-erbα) interacts with the Crebh promoter to repress expression. In short, Bmal1 modulates both the synthesis of primordial lipoproteins and their subsequent expansion into larger lipoproteins by regulating two different proteins, MTP and ApoAIV, through two different transcription factors, Shp and Crebh. It is likely that disruptions in circadian mechanisms contribute to hyperlipidemia and that avoiding disruptions in circadian rhythms may limit/prevent hyperlipidemia and atherosclerosis.


Assuntos
Fatores de Transcrição ARNTL/metabolismo , Aterosclerose , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Hiperlipidemias , Animais , Apolipoproteínas A/metabolismo , Aterosclerose/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
18.
Curr Atheroscler Rep ; 25(5): 209-217, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36913170

RESUMO

PURPOSE OF REVIEW: This review is aimed at providing an overview of new developments in gene editing technology, including examples of how this technology has been used to develop cell models for studying the effects of gene ablation or missense mutations on lipoprotein assembly and secretion. RECENT FINDINGS: CRISPR/Cas9-mediated gene editing is superior to other technologies because of its ease, sensitivity, and low off-target effects. This technology has been used to study the importance of microsomal triglyceride transfer protein in the assembly and secretion of apolipoprotein B-containing lipoproteins, as well as to establish causal effects of APOB gene missense mutations on lipoprotein assembly and secretion. CRISPR/Cas9 technology is anticipated to provide unprecedented flexibility in studying protein structure and function in cells and animals and to yield mechanistic insights into variants in the human genome.


Assuntos
Apolipoproteínas B , Lipoproteínas , Animais , Humanos , Edição de Genes
19.
BJU Int ; 132(3): 337-342, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37169730

RESUMO

OBJECTIVE: To report the oncological survival outcomes of men with penile sarcomatoid squamous cell carcinoma (sSCC). PATIENTS AND METHODS: A retrospective analysis of men with penile sSCC diagnosed between January 2010 and January 2020 in a single centre was conducted. Disease-specific (DSS), recurrence-free (RFS) and metastasis-free (MFS) survival were evaluated. Outcomes were compared with a non-sarcomatoid penile SCC cohort matched to age, type of surgery and tumour stage. Kaplan-Meier plots were used to estimate survival outcomes. RESULTS: In all, 1286 men were diagnosed with penile SCC during the study period and of these 38 (3%) men had sSCC. The median (interquartile range) age and follow-up was 70 (57-81) years and 16 (7-44) months, respectively. Operations performed included: circumcision, one (2.6%); wide local excision, four (10.5%); glansectomy, 11 (29%); partial penectomy, 10 (26%); subtotal/total penectomy, 12 (32%). The Kaplan-Meier estimated 12-, 24- and 36-month DSS was 62% (vs non-sarcomatoid, 67%), 43% (vs non-sarcomatoid, 67%) and 36% (vs non-sarcomatoid, 67%), respectively (P = 0.03). The Kaplan-Meier estimated 12- and 24-month RFS was 47% (vs non-sarcomatoid, 60%) and 28% (vs non-sarcomatoid, 55%), respectively (P = 0.01). The MFS was 52% (vs non-sarcomatoid, 62%) at 12 months and 37% (vs non-sarcomatoid, 57%) at 24 months (P = 0.04). CONCLUSIONS: Sarcomatoid differentiation was associated with a lower DSS, RFS and MFS. Due to the rarity of its incidence and aggressiveness, expert histological review and multidisciplinary management is required in a specialist penile cancer centre.

20.
BJU Int ; 131(1): 73-81, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35986901

RESUMO

OBJECTIVES: To report the management outcomes of men with ≤20-mm small testicular masses (STMs) and to identify clinical and histopathological factors associated with malignancy. PATIENTS AND METHODS: A retrospective analysis of men managed at a single centre between January 2010 and December 2020 with a STM ≤20 mm in size was performed. RESULTS: Overall, 307 men with a median (interquartile range [IQR]) age of 36 (30-44) years were included. Of these, 161 (52.4%), 82 (26.7%), 62 (20.2%) and 2 men (0.7%) underwent surveillance with interval ultrasonography (USS), primary excisional testicular biopsy (TBx) or primary radical orchidectomy (RO), or were discharged, respectively. The median (IQR) surveillance duration was 6 (3-18) months. The majority of men who underwent surveillance had lesions <5 mm (59.0%) and no lesion vascularity (67.1%) on USS. Thirty-three (20.5%) men undergoing surveillance had a TBx based on changes on interval USS or patient choice; seven (21.2%) were found to be malignant. The overall rate of malignancy in the surveillance cohort was 4.3%. The majority of men who underwent primary RO had lesions ≥10 mm (85.5%) and the presence of vascularity (61.7%) on USS. Nineteen men (23.2%) who underwent primary TBx (median lesion size 6 mm) had a malignancy confirmed on biopsy and underwent RO. A total of 88 men (28.7%) underwent RO, and malignancy was confirmed in 73 (83.0%) of them. The overall malignancy rate in the whole STM cohort was 23.8%. Malignant RO specimens had significantly larger lesion sizes (median [IQR] 11 [8-15] mm, vs benign: median [IQR] 8 [5-10] mm; P = 0.04). CONCLUSIONS: Small testicular masses can be stratified and managed based on lesion size and USS features. The overall malignancy rate in men with an STM was 23.8% (4.3% in the surveillance group). Surveillance should be considered in lesions <10 mm in size, with a TBx or frozen-section examination offered prior to RO in order to preserve testicular function.


Assuntos
Neoplasias Testiculares , Masculino , Humanos , Adulto , Feminino , Neoplasias Testiculares/cirurgia , Neoplasias Testiculares/diagnóstico , Estudos Retrospectivos , Orquiectomia , Secções Congeladas , Edema , Equipe de Assistência ao Paciente
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