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2.
Lancet ; 388(10062): e24-e27, 2016 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-27726950

RESUMO

Brexit and the troubled state of the NHS call for re-thinking the UK's approach to health. The EU referendum vote reveals deep social divisions as well as presenting the country with important decisions and negotiations about the future. At the same time, health problems are growing; the NHS faces severe financial constraints and appears to lurch from crisis to crisis, with leaving the European Union likely to exacerbate many problems including staffing issues across the whole sector. However, new scientific developments and digital technology offer societies everywhere massive and unprecedented opportunities for improving health. It is vital for the country that the NHS is able to adopt these discoveries and see them translated into improved patient care and population health, but also that the UK benefits from its capabilities and strengths in these areas.


Assuntos
Pesquisa Biomédica/organização & administração , Atenção à Saúde/organização & administração , Política de Saúde/tendências , Promoção da Saúde/organização & administração , Serviços de Saúde Comunitária , Serviços de Assistência Domiciliar , Humanos , Assistência Centrada no Paciente/métodos , Medicina Estatal , Reino Unido
3.
Am J Community Psychol ; 51(1-2): 264-77, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22688848

RESUMO

Underage drinking continues to be an important public health problem and a challenge to the substance abuse prevention field. Community-based interventions designed to more rigorously control underage access to alcohol through retailer education and greater enforcement of underage drinking laws have been advocated as potentially effective strategies to help address this problem, but studies designed to evaluate such interventions are sparse. To address this issue we conducted a randomized trial involving 36 communities to test the combined effectiveness of five interrelated intervention components designed to reduce underage access to alcohol. The intervention was found to be effective in reducing the likelihood that retail clerks would sell alcohol to underage-looking buyers, but did not reduce underage drinking or the perceived availability of alcohol among high school students. Post hoc analyses, however, revealed significant associations between the level of underage drinking law enforcement in the intervention communities and reductions in both 30-day use of alcohol and binge drinking. The findings highlight the difficulty in reducing youth drinking even when efforts to curtail retail access are successful. Study findings also suggest that high intensity implementation of underage drinking law enforcement can reduce underage drinking. Any such effects of enhanced enforcement on underage drinking appear to be more directly attributable to an increase in perceived likelihood of enforcement and the resultant perceived inconveniences and/or sanctions to potential drinkers, than to a reduction in access to alcohol per se.


Assuntos
Consumo de Bebidas Alcoólicas/prevenção & controle , Bebidas Alcoólicas/provisão & distribuição , Comércio , Pesquisa Participativa Baseada na Comunidade , Adolescente , Adulto , Fatores Etários , Estudos de Coortes , Intervalos de Confiança , Feminino , Humanos , Masculino , Oregon , Distribuição por Sexo , Inquéritos e Questionários
4.
Nurs Manag (Harrow) ; 19(6): 27-30, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23252089

RESUMO

This article considers the benefits to NHS organisations of looking after the health and wellbeing of staff. It also examines the consequences if staff wellbeing is neglected. The author sets out the policy background and the findings of major reviews into health and sickness in working life, generally and in the NHS. At the core of this article is a discussion about the need to establish a culture promoting staff health and wellbeing, to meet the pledges of the NHS Constitution and to respond to the quality and productivity challenges that the NHS faces. The article draws out the essential features of organisations necessary to achieve these goals.


Assuntos
Pessoal de Saúde , Promoção da Saúde/organização & administração , Serviços de Saúde do Trabalhador/organização & administração , Absenteísmo , Humanos , Cultura Organizacional , Medicina Estatal , Reino Unido , Local de Trabalho
6.
Ann Rheum Dis ; 70(1): 32-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20805294

RESUMO

OBJECTIVES: Ischaemic digital ulcers (DUs) are common in patients with systemic sclerosis (SSc) and are a cause of disease-related morbidity. In an earlier trial, treatment with bosentan, an oral endothelin receptor antagonist, reduced the occurrence of new DUs by 48%. The present study (RAPIDS-2, for 'RAndomized, double-blind, Placebo-controlled study with bosentan on healing and prevention of Ischemic Digital ulcers in patients with systemic Sclerosis') was conducted to more fully evaluate the effects of bosentan treatment on DUs associated with SSc. METHODS: This double-blind, placebo-controlled trial conducted at 41 centres in Europe and North America randomised 188 patients with SSc with at least 1 active DU ('cardinal ulcer') to bosentan 62.5 mg twice daily for 4 weeks and 125 mg twice daily thereafter for 20 weeks (n=98) or matching placebo (n=90; total 24 weeks). The two primary end points were the number of new DUs and the time to healing of the cardinal ulcer. Secondary end points included pain, disability and safety. RESULTS: Over 24 weeks, bosentan treatment was associated with a 30% reduction in the number of new DUs compared with placebo (mean ± standard error: 1.9±0.2 vs 2.7±0.3 new ulcers; p=0.04). This effect was greater in patients who entered the trial with more DUs. There was no difference between treatments in healing rate of the cardinal ulcer or secondary end points of pain and disability. Peripheral oedema and elevated aminotransferases were associated with bosentan treatment. CONCLUSIONS: Bosentan treatment reduced the occurrence of new DUs in patients with SSc but had no effect on DU healing. Bosentan was well tolerated and may be a useful adjunct in the management of patients with SSc with recurrent DUs.


Assuntos
Dedos/irrigação sanguínea , Dermatoses da Mão/tratamento farmacológico , Escleroderma Sistêmico/complicações , Úlcera Cutânea/tratamento farmacológico , Sulfonamidas/uso terapêutico , Adulto , Bosentana , Método Duplo-Cego , Esquema de Medicação , Antagonistas dos Receptores de Endotelina , Feminino , Dermatoses da Mão/etiologia , Dermatoses da Mão/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Cutânea/etiologia , Úlcera Cutânea/prevenção & controle , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Resultado do Tratamento , Cicatrização
8.
N Engl J Med ; 357(12): 1210-20, 2007 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-17881752

RESUMO

BACKGROUND: Systemic sclerosis (scleroderma) is a life-threatening autoimmune disease that is characterized by the presence of specific autoantibodies and fibrosis of the skin and major internal organs. METHODS: We genotyped a polymorphism (G-945C) in the promoter of the connective-tissue growth factor (CTGF) gene in 1000 subjects in two groups: group 1, consisting of 200 patients with systemic sclerosis and 188 control subjects; and group 2, consisting of 300 patients with systemic sclerosis and 312 control subjects. The combined groups represented an estimated 10% of patients with systemic sclerosis in the United Kingdom. We tested the effect of the polymorphism on the transcription of CTGF. RESULTS: The GG genotype was significantly more common in patients with systemic sclerosis than in control subjects in both groups, with an odds ratio for the combined group of 2.2 (95% confidence interval [CI], 1.5 to 3.2; P<0.001 for trend). Analysis of the combined group of patients with systemic sclerosis showed a significant association between homozygosity for the G allele and the presence of anti-topoisomerase I antibodies (odds ratio, 3.3; 95% CI, 2.0 to 5.6; P<0.001) and fibrosing alveolitis (odds ratio, 3.1; 95% CI, 1.9 to 5.0; P<0.001). We observed that the substitution of cytosine for guanine created a binding site of the transcriptional regulators Sp1 and Sp3. The C allele has high affinity for Sp3 and is associated with severely reduced transcriptional activity. A chromatin immunoprecipitation assay showed a marked shift in the ratio of Sp1 to Sp3 binding at this region, demonstrating functional relevance in vivo. CONCLUSIONS: The G-945C substitution represses CTGF transcription, and the -945G allele is significantly associated with susceptibility to systemic sclerosis.


Assuntos
Predisposição Genética para Doença , Proteínas Imediatamente Precoces/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Mutação Puntual , Regiões Promotoras Genéticas , Escleroderma Sistêmico/genética , Estudos de Casos e Controles , Fator de Crescimento do Tecido Conjuntivo , Feminino , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Análise de Sequência de DNA , Transcrição Gênica
9.
Mol Biol Cell ; 18(6): 2169-78, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17409352

RESUMO

Transforming growth factor beta (TGFbeta) plays a critical role in connective tissue remodeling by fibroblasts during development, tissue repair, and fibrosis. We investigated the molecular pathways in the transmission of TGFbeta signals that lead to features of connective tissue remodeling, namely formation of an alpha-smooth muscle actin (alpha-SMA) cytoskeleton, matrix contraction, and expression of profibrotic genes. TGFbeta causes the activation of focal adhesion kinase (FAK), leading to JNK phosphorylation. TGFbeta induces JNK-dependent actin stress fiber formation, matrix contraction, and expression of profibrotic genes in fak+/+, but not fak-/-, fibroblasts. Overexpression of MEKK1, a kinase acting upstream of JNK, rescues TGFbeta responsiveness of JNK-dependent transcripts and actin stress fiber formation in FAK-deficient fibroblasts. Thus we propose a FAK-MEKK1-JNK pathway in the transmission of TGFbeta signals leading to the control of alpha-SMA cytoskeleton reorganization, matrix contraction, and profibrotic gene expression and hence to the physiological and pathological effects of TGFbeta on connective tissue remodeling by fibroblasts.


Assuntos
Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Quinase 2 de Adesão Focal/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Ativação Enzimática , Fibroblastos/citologia , Quinase 2 de Adesão Focal/genética , Regulação da Expressão Gênica , Proteínas Quinases JNK Ativadas por Mitógeno/genética , MAP Quinase Quinase Quinase 1/genética , MAP Quinase Quinase Quinase 1/metabolismo , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Fenótipo , Fosforilação , Transdução de Sinais/fisiologia , Fibras de Estresse/metabolismo
10.
Rheumatology (Oxford) ; 48(10): 1218-21, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19696067

RESUMO

OBJECTIVES: Anti-RNA-polymerase antibodies (ARAs) are associated with the diffuse cutaneous subset of SSc (dcSSc) and particularly with scleroderma renal crisis (SRC). We analysed serial ARA levels and explored the relationship with clinical features and disease outcome. METHODS: A commercially available ELISA method with a recombinant peptide of RNA polymerase III was used and ARA levels were measured in a well-characterized cohort of SSc cases. RESULTS: ARA levels were measured in 64 SSc patients. Of them, 78% (n = 50) were females and 92% (n = 59) had dcSSc, 39% (n = 25) had SRC, 20% (n = 13) had pulmonary fibrosis (PF), 9% (n = 6) had pulmonary arterial hypertension and 3% (n = 2) had cardiac involvement. There was considerable inter- and intra-patient variability in ARA levels (11-210 U/ml). There was no correlation between absolute ARA levels (at baseline or throughout the disease course) and outcome. There was a moderate correlation between time to peak ARA level and development of significant PF (Pearson correlation = 0.669, P = 0.034), but no correlation between peak ARA levels and onset of SRC. ARA levels change correlated with change in skin score (correlation coefficient within subjects = 0.236, P = 0.011). CONCLUSIONS: The pathogenic significance of ARA is unclear. Despite the very strong association of ARA with SRC, we could not show the clinically significant association between absolute levels of antibody and development of internal organ complications, which makes repeated measurements of ARA levels unnecessary. However, changes in ARA level over time occur and may reflect changes in skin score.


Assuntos
Anticorpos Antinucleares/sangue , RNA Polimerase III/imunologia , Escleroderma Sistêmico/imunologia , Biomarcadores/sangue , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Seguimentos , Humanos , Masculino
11.
Mol Cell Biol ; 26(14): 5518-27, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16809784

RESUMO

The signal transduction mechanisms generating pathological fibrosis are almost wholly unknown. Endothelin-1 (ET-1), which is up-regulated during tissue repair and fibrosis, induces lung fibroblasts to produce and contract extracellular matrix. Lung fibroblasts isolated from scleroderma patients with chronic pulmonary fibrosis produce elevated levels of ET-1, which contribute to the persistent fibrotic phenotype of these cells. Transforming growth factor beta (TGF-beta) induces fibroblasts to produce and contract matrix. In this report, we show that TGF-beta induces ET-1 in normal and fibrotic lung fibroblasts in a Smad-independent ALK5/c-Jun N-terminal kinase (JNK)/Ap-1-dependent fashion. ET-1 induces JNK through TAK1. Fibrotic lung fibroblasts display constitutive JNK activation, which was reduced by the dual ETA/ETB receptor inhibitor, bosentan, providing evidence of an autocrine endothelin loop. Thus, ET-1 and TGF-beta are likely to cooperate in the pathogenesis of pulmonary fibrosis. As elevated JNK activation in fibrotic lung fibroblasts contributes to the persistence of the myofibroblast phenotype in pulmonary fibrosis by promoting an autocrine ET-1 loop, targeting the ETA and ETB receptors or constitutive JNK activation by fibrotic lung fibroblasts is likely to be of benefit in combating chronic pulmonary fibrosis.


Assuntos
Receptores de Ativinas Tipo I/metabolismo , Endotelina-1/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fibrose Pulmonar/metabolismo , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Actinas/biossíntese , Animais , Células Cultivadas , Antagonistas do Receptor de Endotelina A , Antagonistas do Receptor de Endotelina B , Ativação Enzimática , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Camundongos , Modelos Biológicos , Proteínas Serina-Treonina Quinases , Receptor do Fator de Crescimento Transformador beta Tipo I , Proteínas Smad/metabolismo , Fator de Transcrição AP-1/metabolismo , Fator de Crescimento Transformador beta/farmacologia
12.
Am J Respir Crit Care Med ; 177(11): 1248-54, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18369202

RESUMO

RATIONALE: In interstitial lung disease complicating systemic sclerosis (SSc-ILD), the optimal prognostic use of baseline pulmonary function tests (PFTs) and high-resolution computed tomography (HRCT) is uncertain. OBJECTIVES: To construct a readily applicable prognostic algorithm in SSc-ILD, integrating PFTs and HRCT. METHODS: The prognostic value of baseline PFT and HRCT variables was quantified in patients with SSc-ILD (n = 215) against survival and serial PFT data. MEASUREMENTS AND MAIN RESULTS: Increasingly extensive disease on HRCT was a powerful predictor of mortality (P < 0.0005), with an optimal extent threshold of 20%. In patients with HRCT extent of 10-30% (termed indeterminate disease), an FVC threshold of 70% was an adequate prognostic substitute. On the basis of these observations, SSc-ILD was staged as limited disease (minimal disease on HRCT or, in indeterminate cases, FVC >or= 70%) or extensive disease (severe disease on HRCT or, in indeterminate cases, FVC < 70%). This system (hazards ratio [HR], 3.46; 95% confidence interval [CI], 2.19-5.46; P < 0.0005) was more discriminatory than an HRCT threshold of 20% (HR, 2.48; 95% CI, 1.57-3.92; P < 0.0005) or an FVC threshold of 70% (HR, 2.11; 95% CI, 1.34-3.32; P = 0.001). The system was evaluated by four trainees and four practitioners, with minimal and severe disease on HRCT defined as clearly < 20% or clearly > 20%, respectively, and the use of an FVC threshold of 70% in indeterminate cases. The staging system was predictive of mortality for all scorers, with prognostic separation higher for practitioners (HR, 3.39-3.82) than trainees (HR, 1.87-2.60). CONCLUSIONS: An easily applicable limited/extensive staging system for SSc-ILD, based on combined evaluation with HRCT and PFTs, provides discriminatory prognostic information.


Assuntos
Algoritmos , Doenças Pulmonares Intersticiais/diagnóstico , Escleroderma Sistêmico/complicações , Índice de Gravidade de Doença , Adulto , Estudos de Coortes , Feminino , Humanos , Doenças Pulmonares Intersticiais/etiologia , Doenças Pulmonares Intersticiais/mortalidade , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Escleroderma Sistêmico/diagnóstico por imagem , Escleroderma Sistêmico/fisiopatologia , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Capacidade Vital/fisiologia
13.
JAMA ; 302(18): 2008-14, 2009 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-19903922

RESUMO

In the United States, Canada, and the United Kingdom, the medical profession is accountable to the public for the delivery and quality of care provided to patients. Traditionally, this accountability has been achieved through the development and maintenance of professional standards established by the profession itself-self-regulation. Medical self-regulation is being re-examined by regulators, government, and the profession in response to a range of drivers including payers seeking ways to hold physicians accountable for cost-effective care; patients seeking more information about their physician's qualifications; and the emergence of a number of high-profile cases of unacceptable medical practice. This article outlines the current state of medical regulation in the United States, Canada, and the United Kingdom and highlights the increasing external pressure on the self-regulatory framework that is leading to a shift toward shared regulation between the profession and other stakeholders.


Assuntos
Revelação/normas , Papel do Médico , Qualidade da Assistência à Saúde/normas , Controle Social Formal , Canadá , Certificação , Humanos , Licenciamento , Autonomia Profissional , Qualidade da Assistência à Saúde/ética , Controle Social Formal/métodos , Responsabilidade Social , Reino Unido , Estados Unidos
15.
Chest ; 134(4): 775-782, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18625676

RESUMO

BACKGROUND: Despite advances in the management of pulmonary arterial hypertension (PAH), the mortality rate remains excessive. Long-term efficacy evaluations are needed to guide therapeutic management. The purpose of this study is to present 1-year observational data with two endothelin antagonists, sitaxsentan and bosentan, in a prospective, open-label study. METHODS: The present study was a prospective, international, multicenter, randomized, open-label extension of the Sitaxsentan To Relieve Impaired Exercise-2 trial. All-cause mortality, time to discontinuation (all causes) from monotherapy, time to discontinuation due to adverse events, time to elevations in and time to discontinuation due to elevated hepatic transaminases, and time to first clinical worsening event were evaluated. Patients initially receiving sitaxsentan at 50 mg were excluded from the main analysis. The distributions of time-to-event variables are estimated using Kaplan-Meier methods, and treatment effects are evaluated using the Cox proportional hazards model. RESULTS: Patients treated with sitaxsentan at 100 mg had 96% overall survival and a 34% risk for a clinical worsening event by 1 year. In addition, there was a 6% risk of elevated aspartate aminotransferase (AST) and/or alanine aminotransferase (ALT) levels > 3 x upper limit of normal range (ULN) at 1 year and a 15% risk of discontinuation due to adverse events. Patients treated with bosentan had 88% overall survival and a 40% risk of a clinical worsening event by 1 year. In addition, there was a 14% risk for elevated AST and/or ALT levels > 3 x ULN at 1 year and a 30% risk of discontinuation due to adverse events. CONCLUSIONS: At 1 year, sitaxsentan therapy appears safe and efficacious for patients with PAH; reductions in mortality and the risk for clinical worsening events provide support for durability of efficacy.


Assuntos
Antagonistas dos Receptores de Endotelina , Hipertensão Pulmonar/tratamento farmacológico , Isoxazóis/uso terapêutico , Tiofenos/uso terapêutico , Adolescente , Adulto , Idoso , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Hipertensão Pulmonar/mortalidade , Isoxazóis/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida , Tiofenos/administração & dosagem , Fatores de Tempo , Resultado do Tratamento
16.
Matrix Biol ; 26(8): 625-32, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17681742

RESUMO

Fibrosis is excessive scarring caused by the accumulation of extracellular matrix proteins and is a common end pathway in many chronic diseases. Endothelin-1 is a possible contributor to the persistent fibrotic phenotype of fibroblasts isolated from fibrotic lesions. In this report we used a specific dual endothelin A/B receptor antagonist, bosentan, to determine the role of endogenous endothelin signaling in maintaining the profibrotic phenotype of lung fibroblasts from scleroderma patients. Bosentan treatment of lung fibroblasts cultured from normal individuals and individuals with scleroderma was assessed using Affymetrix genome-wide expression profiling, real-time polymerase chain reaction and Western blot analysis and revealed that approximately one-third of the transcripts elevated greater than two-fold in fibrotic fibroblasts were reduced by Bosentan treatment. Genes whose overexpression in fibrotic fibroblasts that were dependent on endogenous endothelin signaling included the matrix or matrix-associated genes type I collagen, fibronectin and CCN2. The elevated adhesive property of fibrotic fibroblasts was also reduced by endothelin receptor antagonism. Basal expression of collagen, fibronectin and CCN2 and adhesion to matrix was not affected. Thus endogenous endothelin signaling contributes to the fibrotic phenotype of fibrotic fibroblasts, suggesting that antagonizing endothelin receptors may be of benefit in combating fibrotic disease.


Assuntos
Colágeno Tipo I/metabolismo , Endotelina-1/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Transdução de Sinais , Biópsia , Bosentana , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Fator de Crescimento do Tecido Conjuntivo , Antagonistas do Receptor de Endotelina A , Antagonistas do Receptor de Endotelina B , Fibroblastos , Fibrose/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , RNA Mensageiro/genética , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/metabolismo , Escleroderma Sistêmico/genética , Escleroderma Sistêmico/metabolismo , Escleroderma Sistêmico/patologia , Sulfonamidas/farmacologia
17.
Free Radic Biol Med ; 43(2): 253-64, 2007 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-17603934

RESUMO

Nitric oxide ((.-)NO) is an important physiological signaling molecule and potent vasodilator. Recently, we have shown abnormal (.-)NO metabolism in the plasma of patients with systemic sclerosis (SSc), a disease that features excessive collagen overproduction as well as vascular dysfunction. The current study investigates the effects of (.-)NO and peroxynitrite (ONOO(-)) on secretion of type I collagen by SSc dermal fibroblasts, compared with those from normal dermal fibroblasts (CON) and a dermal fibroblast cell line (AG). Dermal fibroblasts were incubated with (.-)NO donors (SNP, DETA-NONOate) with or without the antioxidant ascorbic acid, or ONOO(-) for 24-72 h. In CON and AG fibroblasts, type I collagen was dose dependently decreased by SNP or DETA-NONOate. However, (.-)NO had no effect in SSc fibroblasts. Furthermore, the inhibition of collagen synthesis by (.-)NO was reversed by ascorbic acid and was not affected by 1H-[1,2,4]oxadiazole[4,3-a]quinoxalin-1-one, an inhibitor of soluble guanyl cyclase, or 8-bromoguanosine cyclic 3',5'-monophosphate, a cGMP agonist. SNP also showed a significant up-regulation of matrix metalloproteinase-1 (MMP-1) protein and activity levels, an essential collagenase involved in collagen degradation, in the AG fibroblasts. Additionally, (.-)NO-treated fibroblasts had lower prolyl hydroxylase activity, an enzyme important in the post-translational processing of collagen, while there was no effect on total protein levels. There were no significant effects on type I collagen levels when dermal fibroblasts were treated with ONOO(-). Taken together, ()NO inhibits collagen secretion in normal dermal fibroblasts but regulation is lost in SSc fibroblasts, while ONOO(-) itself is ineffective. (.-)NO inhibition of collagen was by cGMP-independent regulatory mechanisms and in part may be due to up-regulation of MMP-1 and/or inhibition of prolyl hydroxylase. These differences may contribute to the observed pathology of SSc.


Assuntos
Colágeno Tipo I/biossíntese , Fibroblastos/metabolismo , Óxido Nítrico/farmacologia , Ácido Peroxinitroso/farmacologia , Escleroderma Sistêmico/metabolismo , Pele/metabolismo , Ácido Ascórbico/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Colágeno Tipo I/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Cinética , Nitroprussiato/farmacologia , Cianeto de Potássio/farmacologia , Escleroderma Sistêmico/patologia , Pele/efeitos dos fármacos , Pele/patologia
18.
N Engl J Med ; 346(12): 896-903, 2002 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-11907289

RESUMO

BACKGROUND: Endothelin-1 is a potent vasoconstrictor and smooth-muscle mitogen. In a preliminary study, the orally administered dual endothelin-receptor antagonist bosentan improved exercise capacity and cardiopulmonary hemodynamics in patients with pulmonary arterial hypertension. The present trial investigated the effect of bosentan on exercise capacity in a larger number of patients and compared two doses. METHODS: In this double-blind, placebo-controlled study, we randomly assigned 213 patients with pulmonary arterial hypertension (primary or associated with connective-tissue disease) to receive placebo or to receive 62.5 mg of bosentan twice daily for 4 weeks followed by either of two doses of bosentan (125 or 250 mg twice daily) for a minimum of 12 weeks. The primary end point was the degree of change in exercise capacity. Secondary end points included the change in the Borg dyspnea index, the change in the World Health Organization (WHO) functional class, and the time to clinical worsening. RESULTS: At week 16, patients treated with bosentan had an improved six-minute walking distance; the mean difference between the placebo group and the combined bosentan groups was 44 m (95 percent confidence interval, 21 to 67; P<0.001). Bosentan also improved the Borg dyspnea index and WHO functional class and increased the time to clinical worsening. CONCLUSIONS: The endothelin-receptor antagonist bosentan is beneficial in patients with pulmonary arterial hypertension and is well tolerated at a dose of 125 mg twice daily. Endothelin-receptor antagonism with oral bosentan is an effective approach to therapy for pulmonary arterial hypertension.


Assuntos
Anti-Hipertensivos/uso terapêutico , Antagonistas dos Receptores de Endotelina , Hipertensão Pulmonar/tratamento farmacológico , Sulfonamidas/uso terapêutico , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Bosentana , Criança , Método Duplo-Cego , Tolerância ao Exercício/efeitos dos fármacos , Feminino , Humanos , Hipertensão Pulmonar/classificação , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/fisiopatologia , Fígado/efeitos dos fármacos , Lúpus Eritematoso Sistêmico/complicações , Masculino , Pessoa de Meia-Idade , Escleroderma Sistêmico/complicações , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Caminhada
20.
Mol Cell Biol ; 24(14): 6151-61, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15226419

RESUMO

A major component of the vessel wall of large arteries and veins is the extracellular matrix (ECM), which consists of collagens, elastin, and proteoglycans. Collagen type I is one of the most abundant of the ECM proteins. We have previously shown that the pro-collagen type I alpha 2 gene contains an enhancer which confers tissue-specific expression in the majority of collagen-producing cells, including blood vessels. In this paper, we delineate a specific vascular smooth muscle cell (vSMC) element: a 100-bp sequence around -16.6 kb upstream of the transcription start site that regulates collagen expression exclusively in vSMCs. Furthermore, we show that the expression is activated through the binding of the homeodomain protein Nkx2.5, which is further potentiated in the presence of GATA6. In contrast, this element was repressed by the binding of the zinc-finger protein deltaEF1/ZEB1. We propose a model of regulation where the activating transcription factor Nkx2.5 and the repressor deltaEF1/ZEB1 compete for an overlapping DNA binding site. This element is important in understanding the molecular mechanisms of vessel remodeling and is a potential target for intervention in vascular diseases where there is excessive deposition of collagen in the vessel wall.


Assuntos
Colágeno Tipo I/metabolismo , Regulação da Expressão Gênica , Proteínas de Homeodomínio/metabolismo , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Células Cultivadas , Colágeno Tipo I/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Fator de Transcrição GATA6 , Genes Reporter , Proteína Homeobox Nkx-2.5 , Proteínas de Homeodomínio/genética , Humanos , Camundongos , Modelos Genéticos , Dados de Sequência Molecular , Miócitos de Músculo Liso/citologia , Ligação Proteica , Ratos , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco , Dedos de Zinco
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