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1.
N Engl J Med ; 376(25): 2437-2447, 2017 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-28636854

RESUMO

BACKGROUND: The role of supine positioning after acute stroke in improving cerebral blood flow and the countervailing risk of aspiration pneumonia have led to variation in head positioning in clinical practice. We wanted to determine whether outcomes in patients with acute ischemic stroke could be improved by positioning the patient to be lying flat (i.e., fully supine with the back horizontal and the face upwards) during treatment to increase cerebral perfusion. METHODS: In a pragmatic, cluster-randomized, crossover trial conducted in nine countries, we assigned 11,093 patients with acute stroke (85% of the strokes were ischemic) to receive care in either a lying-flat position or a sitting-up position with the head elevated to at least 30 degrees, according to the randomization assignment of the hospital to which they were admitted; the designated position was initiated soon after hospital admission and was maintained for 24 hours. The primary outcome was degree of disability at 90 days, as assessed with the use of the modified Rankin scale (scores range from 0 to 6, with higher scores indicating greater disability and a score of 6 indicating death). RESULTS: The median interval between the onset of stroke symptoms and the initiation of the assigned position was 14 hours (interquartile range, 5 to 35). Patients in the lying-flat group were less likely than patients in the sitting-up group to maintain the position for 24 hours (87% vs. 95%, P<0.001). In a proportional-odds model, there was no significant shift in the distribution of 90-day disability outcomes on the global modified Rankin scale between patients in the lying-flat group and patients in the sitting-up group (unadjusted odds ratio for a difference in the distribution of scores on the modified Rankin scale in the lying-flat group, 1.01; 95% confidence interval, 0.92 to 1.10; P=0.84). Mortality within 90 days was 7.3% among the patients in the lying-flat group and 7.4% among the patients in the sitting-up group (P=0.83). There were no significant between-group differences in the rates of serious adverse events, including pneumonia. CONCLUSIONS: Disability outcomes after acute stroke did not differ significantly between patients assigned to a lying-flat position for 24 hours and patients assigned to a sitting-up position with the head elevated to at least 30 degrees for 24 hours. (Funded by the National Health and Medical Research Council of Australia; HeadPoST ClinicalTrials.gov number, NCT02162017 .).


Assuntos
Posicionamento do Paciente , Postura , Acidente Vascular Cerebral/terapia , Idoso , Estudos Cross-Over , Avaliação da Deficiência , Feminino , Cabeça , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/mortalidade
2.
Genes Dis ; 10(4): 1351-1366, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37397543

RESUMO

Recent advances in deep sequencing technologies have revealed that, while less than 2% of the human genome is transcribed into mRNA for protein synthesis, over 80% of the genome is transcribed, leading to the production of large amounts of noncoding RNAs (ncRNAs). It has been shown that ncRNAs, especially long non-coding RNAs (lncRNAs), may play crucial regulatory roles in gene expression. As one of the first isolated and reported lncRNAs, H19 has gained much attention due to its essential roles in regulating many physiological and/or pathological processes including embryogenesis, development, tumorigenesis, osteogenesis, and metabolism. Mechanistically, H19 mediates diverse regulatory functions by serving as competing endogenous RNAs (CeRNAs), Igf2/H19 imprinted tandem gene, modular scaffold, cooperating with H19 antisense, and acting directly with other mRNAs or lncRNAs. Here, we summarized the current understanding of H19 in embryogenesis and development, cancer development and progression, mesenchymal stem cell lineage-specific differentiation, and metabolic diseases. We discussed the potential regulatory mechanisms underlying H19's functions in those processes although more in-depth studies are warranted to delineate the exact molecular, cellular, epigenetic, and genomic regulatory mechanisms underlying the physiological and pathological roles of H19. Ultimately, these lines of investigation may lead to the development of novel therapeutics for human diseases by exploiting H19 functions.

3.
J Biol Chem ; 285(18): 13498-506, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20167598

RESUMO

The classical nuclear factor kappaB (NF-kappaB) signaling pathway is under the control of the IkappaB kinase (IKK) complex, which consists of IKK-1, IKK-2, and NF-kappaB essential modulator (NEMO). This complex is responsible for the regulation of cell proliferation, survival, and differentiation. Dysregulation of this pathway is associated with several human diseases, and as such, its inhibition offers an exciting opportunity for therapeutic intervention. NEMO binding domain (NBD) peptides inhibit the binding of recombinant NEMO to IKK-2 in vitro. However, direct evidence of disruption of this binding by NBD peptides in biological systems has not been provided. Using a cell system, we expanded on previous observations to show that NBD peptides inhibit inflammation-induced but not basal cytokine production. We report that these peptides cause the release of IKK-2 from an IKK complex and disrupt NEMO-IKK-2 interactions in cells. We demonstrate that by interfering with NEMO-IKK-2 interactions, NBD peptides inhibit IKK-2 phosphorylation, without affecting signaling intermediates upstream of the IKK complex of the NF-kappaB pathway. Furthermore, in a cell-free system of IKK complex activation by TRAF6 (TNF receptor-associated factor 6), we show that these peptides inhibit the ability of this complex to phosphorylate downstream substrates, such as p65 and inhibitor of kappaB alpha (IkappaB alpha). Thus, consistent with the notion that NEMO regulates IKK-2 catalytic activity by serving as a scaffold, appropriately positioning IKK-2 for activation by upstream kinase(s), our findings provide novel insights into the molecular mechanisms by which NBD peptides exert their anti-inflammatory effects in cells.


Assuntos
Anti-Inflamatórios/farmacologia , Quinase I-kappa B/metabolismo , Quinase I-kappa B/farmacologia , Complexos Multiproteicos/metabolismo , Peptídeos/farmacologia , Fator de Transcrição RelA/metabolismo , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Humanos , Quinase I-kappa B/antagonistas & inibidores , Quinase I-kappa B/química , Complexos Multiproteicos/antagonistas & inibidores , Peptídeos/química , Peptídeos/metabolismo , Fosforilação , Ligação Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína , Fator 6 Associado a Receptor de TNF/metabolismo , Fator de Transcrição RelA/antagonistas & inibidores
4.
Osteoarthritis Cartilage ; 18(7): 948-55, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20417291

RESUMO

OBJECTIVE: Statins possess anti-inflammatory properties. This study was undertaken to characterize the mechanism of action of statin drugs on collagenase expression in primary human osteoarthritic cartilage tissue. METHOD: Human articular chondrocytes and cartilage explants from osteoarthritic donors were exposed to simvastatin in the presence or absence of interleukin-1 beta (IL-1beta). Collagenase expression was determined by quantifying levels of matrix metalloproteinase 13 (MMP-13) and MMP-1 mRNA and MMP-13 protein. The mechanism of statin action was tested by addition of farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP) or by using inhibitors of farnesyl transferase (FT) and geranylgeranyl transferase (GGT-1). RESULTS: Treatment of osteoarthritic chondrocytes with simvastatin decreased mRNA levels of MMP-13 and MMP-1 whether under basal conditions or during stimulation with IL-1beta. MMP-13 protein secreted into the culture media was also decreased. Genes involved in cartilage synthesis (type II collagen and aggrecan) were not down-regulated by simvastatin. Exogenous addition of GGPP completely reversed the statin-mediated decrease in MMP-13 mRNA and protein levels whereas FPP partially reversed the statin-mediated effect. An inhibitor of GGT-1 mimicked the simvastatin-mediated reduction in MMP-13 expression by chondrocytes. Finally, consistent with impacts on MMP-13 and MMP-1 expression, simvastatin as well as the GGT-1 inhibitor both blocked type II collagen degradation in primary human articular cartilage explants. CONCLUSION: These results suggest that statins modulate chondrocyte metabolism by reducing prenylation of key signaling molecules that control the expression of collagen-degrading enzymes. Our results strongly support the hypothesis that protein prenyltransferases including geranylgeranyl transferase regulate chondrocyte collagenase expression in osteoarthritis.


Assuntos
Condrócitos/efeitos dos fármacos , Colagenases/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Osteoartrite/metabolismo , Prenilação de Proteína/efeitos dos fármacos , Sinvastatina/farmacologia , Análise de Variância , Cartilagem Articular/efeitos dos fármacos , Células Cultivadas , Colagenases/genética , Humanos , Osteoartrite/genética , Prenilação de Proteína/genética
5.
J Hypertens ; 37(7): 1463-1466, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31085948

RESUMO

BACKGROUND AND PURPOSE: An early elevation in blood pressure (BP) is common after spontaneous intracerebral hemorrhage (ICH), has various potential causes, and is predictive of poor outcome. We aimed to determine the predictors of this phenomenon, in pooled analyses of the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trials [INTERACT1 (n = 404) and INTERACT2 (n = 2829)]. METHODS: INTERACT trials were international, open, blinded endpoint, randomized controlled trials of patients with spontaneous ICH (<6 h) and elevated SBP (150-220 mmHg) assigned to intensive (target SBP < 140 mmHg) or guideline-recommended (SBP < 180 mmHg) treatment. Multivariable linear and logistic regression models were used to determine associations between baseline variables and the high admission BP, with continuous and binary SBP measures, respectively. RESULTS: Among 3233 patients (mean age 63 years; 37% female; baseline mean SBP 179 mmHg), both analytic approaches showed significant positive associations of high admission BP with history of hypertension, admission hyperglycemia at least 6.5 mmol/l, elevated heart rate, and greater neurological severity (National Institutes of Health Stroke Scale scores); and significant negative associations with prior use of antithrombotic agents and longer time from onset to randomization. CONCLUSION: The high admission BP of mild-to-moderate acute ICH is related to autonomic nervous system activated 'stress' rather than hematoma location and mass effect. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00226096 and NCT00716079.


Assuntos
Pressão Sanguínea , Hemorragia Cerebral/diagnóstico por imagem , Hematoma/complicações , Hipertensão/tratamento farmacológico , Hipotensão/complicações , Idoso , Anti-Hipertensivos/uso terapêutico , Determinação da Pressão Arterial , Hemorragia Cerebral/complicações , Feminino , Fibrinolíticos/uso terapêutico , Hospitalização , Humanos , Hiperglicemia , Hipertensão/complicações , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Admissão do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
6.
J Am Heart Assoc ; 8(13): e012640, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31237173

RESUMO

Background The uptake of proven stroke treatments varies widely. We aimed to determine the association of evidence-based processes of care for acute ischemic stroke ( AIS ) and clinical outcome of patients who participated in the HEADPOST (Head Positioning in Acute Stroke Trial), a multicenter cluster crossover trial of lying flat versus sitting up, head positioning in acute stroke. Methods and Results Use of 8 AIS processes of care were considered: reperfusion therapy in eligible patients; acute stroke unit care; antihypertensive, antiplatelet, statin, and anticoagulation for atrial fibrillation; dysphagia assessment; and physiotherapist review. Hierarchical, mixed, logistic regression models were performed to determine associations with good outcome (modified Rankin Scale scores 0-2) at 90 days, adjusted for patient and hospital variables. Among 9485 patients with AIS, implementation of all processes of care in eligible patients, or "defect-free" care, was associated with improved outcome (odds ratio, 1.40; 95% CI, 1.18-1.65) and better survival (odds ratio, 2.23; 95% CI , 1.62-3.09). Defect-free stroke care was also significantly associated with excellent outcome (modified Rankin Scale score 0-1) (odds ratio, 1.22; 95% CI , 1.04-1.43). No hospital characteristic was independently predictive of outcome. Only 1445 (15%) of eligible patients with AIS received all processes of care, with significant regional variations in overall and individual rates. Conclusions Use of evidence-based care is associated with improved clinical outcome in AIS . Strategies are required to address regional variation in the use of proven AIS treatments. Clinical Trial Registration URL : https://www.clinicaltrials.gov . Unique Identifier: NCT02162017.


Assuntos
Isquemia Encefálica/terapia , Medicina Baseada em Evidências , Avaliação de Processos e Resultados em Cuidados de Saúde , Acidente Vascular Cerebral/terapia , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Austrália , Isquemia Encefálica/fisiopatologia , China , Transtornos de Deglutição/diagnóstico , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Índia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multinível , Posicionamento do Paciente , Modalidades de Fisioterapia/estatística & dados numéricos , Inibidores da Agregação Plaquetária/uso terapêutico , América do Sul , Sri Lanka , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/fisiopatologia , Taiwan , Trombectomia/estatística & dados numéricos , Terapia Trombolítica/estatística & dados numéricos , Reino Unido
7.
Stroke Vasc Neurol ; 2(2): 53-58, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28959492

RESUMO

BACKGROUND: The characteristics of patients with acute ischaemic stroke (AIS) and their management vary across regions, which may influence outcomes. We examined for differential patterns of outcome between China and non-China participants of the ENhanced Control of Hypertension And Thrombolysis strokE stuDy (ENCHANTED), which tested different alteplase doses in AIS. METHODS: ENCHANTED was an international, multicentre, open, blinded-endpoint trial of the effects of low-dose (0.6 mg/kg) versus standard-dose (0.9 mg/kg) intravenous alteplase on 90-day disability outcomes and symptomatic intracerebral haemorrhage (sICH) in 3310 patients with AIS. RESULTS: Participants (n=1419, 48%) in China were younger, and more often male, hypertensive and with prior stroke and coronary artery disease, but less likely to have atrial fibrillation and use antihypertensive, antithrombotic and lipid-lowering agents, compared with non-China patients with AIS. Although China participants had more AIS due to large artery occlusion, were treated later and had differing ancillary management, there was no significant difference in 90-day modified Rankin scale scores 2-6 (55.6% vs 47.8%; OR, adjusted for baseline and management factors 0.87 (95% CI 0.71 to 1.07; p=0.20)) and risk of sICH (Safe Implementation of Thrombolysis in Stroke-Monitoring Study criteria: 1.4% vs 1.8%; p=0.12) compared with non-China participants. There was no heterogeneity in the treatment effects of low-dose versus standard-dose alteplase between China and non-China participants. CONCLUSION: Patients with AIS recruited to the ENCHANTED trial in China had similar outcomes in response to thrombolysis treatment despite significantly differing demographic, clinical and management factors to patients with AIS in other regions.


Assuntos
Fibrinolíticos/administração & dosagem , AVC Isquêmico/tratamento farmacológico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Hemorragia Cerebral/induzido quimicamente , China/epidemiologia , Avaliação da Deficiência , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Infusões Intravenosas , AVC Isquêmico/diagnóstico , AVC Isquêmico/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recuperação de Função Fisiológica , Fatores de Risco , Terapia Trombolítica/efeitos adversos , Fatores de Tempo , Ativador de Plasminogênio Tecidual/efeitos adversos , Resultado do Tratamento
8.
Int J Stroke ; 12(6): 667-670, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28730950

RESUMO

Background There is evidence to indicate that the lying flat head position increases cerebral blood flow and oxygenation in patients with acute ischemic stroke, but how these physiological effects translate into clinical outcomes is uncertain. The Head Position in Stroke Trial aims to determine the comparative effectiveness of lying flat (0°) compared to sitting up (≥30°) head positioning, initiated within 24 h of hospital admission for patients with acute stroke. Design An international, pragmatic, cluster-randomized, crossover, open, blinded outcome assessed clinical trial. Each hospital with an established acute stroke unit (cluster) site was required to recruit up to 140 consecutive cases of acute stroke (one phase of head positioning before immediately crossing over to the other phase of head positioning), including both acute ischemic stroke and intracerebral hemorrhage, in each randomized head position as a 'business as usual' policy. Objective To outline in detail the predetermined statistical analysis plan for the study. Methods All accumulated data will be reviewed and formally assessed. Information regarding baseline characteristics of patients, their process of care and management will be outlined, and for each item, statistically relevant descriptive elements will be described. For the trial outcomes, the most appropriate statistical comparisons are described. Results A statistical analysis plan was developed that is transparent, verifiable, and predetermined before completion of data collection. Conclusions We developed a predetermined statistical analysis plan for Head Position in Stroke Trial to avoid analysis bias arising from prior knowledge of the findings, in order to reliably quantify the benefits and harms of lying flat versus sitting up early after the onset of acute stroke. Trial registration ClinicalTrials.gov identifier NCT02162017; ANZCTR identifier ACTRN12614000483651.


Assuntos
Isquemia Encefálica/fisiopatologia , Hemorragia Cerebral/fisiopatologia , Posicionamento do Paciente/estatística & dados numéricos , Postura/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Circulação Cerebrovascular/fisiologia , Estudos Cross-Over , Humanos , Resultado do Tratamento
9.
J Neurol Sci ; 371: 126-130, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27871433

RESUMO

BACKGROUND: Few studies have assessed regional variation in the organisation of stroke services, particularly health care resourcing, presence of protocols and discharge planning. Our aim was to compare stroke care organisation within middle- (MIC) and high-income country (HIC) hospitals participating in the Head Position in Stroke Trial (HeadPoST). METHODS: HeadPoST is an on-going international multicenter crossover cluster-randomized trial of 'sitting-up' versus 'lying-flat' head positioning in acute stroke. As part of the start-up phase, one stroke care organisation questionnaire was completed at each hospital. The World Bank gross national income per capita criteria were used for classification. RESULTS: 94 hospitals from 9 countries completed the questionnaire, 51 corresponding to MIC and 43 to HIC. Most participating hospitals had a dedicated stroke care unit/ward, with access to diagnostic services and expert stroke physicians, and offering intravenous thrombolysis. There was no difference for the presence of a dedicated multidisciplinary stroke team, although greater access to a broad spectrum of rehabilitation therapists in HIC compared to MIC hospitals was observed. Significantly more patients arrived within a 4-h window of symptoms onset in HIC hospitals (41 vs. 13%; P<0.001), and a significantly higher proportion of acute ischemic stroke patients received intravenous thrombolysis (10 vs. 5%; P=0.002) compared to MIC hospitals. CONCLUSIONS: Although all hospitals provided advanced care for people with stroke, differences were found in stroke care organisation and treatment. Future multilevel analyses aims to determine the influence of specific organisational factors on patient outcomes.


Assuntos
Hospitais , Acidente Vascular Cerebral/terapia , Isquemia Encefálica/economia , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/terapia , Protocolos Clínicos , Estudos Cross-Over , Mão de Obra em Saúde/economia , Número de Leitos em Hospital/economia , Humanos , Alta do Paciente/economia , Posicionamento do Paciente , Garantia da Qualidade dos Cuidados de Saúde/economia , Fatores Socioeconômicos , Acidente Vascular Cerebral/economia , Acidente Vascular Cerebral/epidemiologia , Inquéritos e Questionários , Terapia Trombolítica/economia
10.
Trials ; 16: 256, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-26040944

RESUMO

BACKGROUND: Positioning a patient lying-flat in the acute phase of ischaemic stroke may improve recovery and reduce disability, but such a possibility has not been formally tested in a randomised trial. We therefore initiated the Head Position in Stroke Trial (HeadPoST) to determine the effects of lying-flat (0°) compared with sitting-up (≥ 30°) head positioning in the first 24 hours of hospital admission for patients with acute stroke. METHODS/DESIGN: We plan to conduct an international, cluster randomised, crossover, open, blinded outcome-assessed clinical trial involving 140 study hospitals (clusters) with established acute stroke care programs. Each hospital will be randomly assigned to sequential policies of lying-flat (0°) or sitting-up (≥ 30°) head position as a 'business as usual' stroke care policy during the first 24 hours of admittance. Each hospital is required to recruit 60 consecutive patients with acute ischaemic stroke (AIS), and all patients with acute intracerebral haemorrhage (ICH) (an estimated average of 10), in the first randomised head position policy before crossing over to the second head position policy with a similar recruitment target. After collection of in-hospital clinical and management data and 7-day outcomes, central trained blinded assessors will conduct a telephone disability assessment with the modified Rankin Scale at 90 days. The primary outcome for analysis is a shift (defined as improvement) in death or disability on this scale. For a cluster size of 60 patients with AIS per intervention and with various assumptions including an intracluster correlation coefficient of 0.03, a sample size of 16,800 patients at 140 centres will provide 90 % power (α 0.05) to detect at least a 16 % relative improvement (shift) in an ordinal logistic regression analysis of the primary outcome. The treatment effect will also be assessed in all patients with ICH who are recruited during each treatment study period. DISCUSSION: HeadPoST is a large international clinical trial in which we will rigorously evaluate the effects of different head positioning in patients with acute stroke. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02162017 (date of registration: 27 April 2014); ANZCTR identifier: ACTRN12614000483651 (date of registration: 9 May 2014). Protocol version and date: version 2.2, 19 June 2014.


Assuntos
Hemorragia Cerebral/terapia , Circulação Cerebrovascular , Cabeça/irrigação sanguínea , Posicionamento do Paciente/métodos , Acidente Vascular Cerebral/terapia , Decúbito Dorsal , Ásia , Austrália , Brasil , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/mortalidade , Hemorragia Cerebral/fisiopatologia , Chile , Protocolos Clínicos , Estudos Cross-Over , Avaliação da Deficiência , Humanos , Modelos Logísticos , Posicionamento do Paciente/efeitos adversos , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Tamanho da Amostra , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Reino Unido
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