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1.
J Hepatol ; 61(1): 75-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24607626

RESUMO

BACKGROUND & AIMS: Subtle inter-patient genetic variation and environmental factors combine to determine disease progression in non-alcoholic fatty liver disease (NAFLD). Carriage of the PNPLA3 rs738409 c.444C >G minor allele (encoding the I148M variant) has been robustly associated with advanced NAFLD. Although most hepatocellular carcinoma (HCC) is related to chronic viral hepatitis or alcoholic liver disease, the incidence of NAFLD-related HCC is increasing. We examined whether rs738409 C >G was associated with HCC-risk in patients with NAFLD. METHODS: PNPLA3 rs738409 genotype was determined by allelic discrimination in 100 European Caucasians with NAFLD-related HCC and 275 controls with histologically characterised NAFLD. RESULTS: Genotype frequencies were significantly different between NAFLD-HCC cases (CC=28, CG=43, GG=29) and NAFLD-controls (CC=125, CG=117, GG=33) (p=0.0001). In multivariate analysis adjusted for age, gender, diabetes, BMI, and presence of cirrhosis, carriage of each copy of the rs738409 minor (G) allele conferred an additive risk for HCC (adjusted OR 2.26 [95% CI 1.23-4.14], p=0.0082), with GG homozygotes exhibiting a 5-fold [1.47-17.29], p=0.01 increased risk over CC. When compared to the UK general population (1958 British Birth Cohort, n=1476), the risk-effect was more pronounced (GC vs. CC: unadjusted OR 2.52 [1.55-4.10], p=0.0002; GG vs. CC: OR 12.19 [6.89-21.58], p<0.0001). CONCLUSIONS: Carriage of the PNPLA3 rs738409 C >G polymorphism is not only associated with greater risk of progressive steatohepatitis and fibrosis but also of HCC. If validated, these findings suggest that PNPLA3 genotyping has the potential to contribute to multi-factorial patient-risk stratification, identifying those to whom HCC surveillance may be targeted.


Assuntos
Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/genética , Lipase/genética , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Progressão da Doença , Feminino , Frequência do Gene , Estudos de Associação Genética , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/patologia , Fatores de Risco , População Branca/genética
3.
Gut ; 59(2): 267-73, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20176643

RESUMO

BACKGROUND/AIMS: The aim of this study was to assess the effect of functional ENPP1(ectoenzyme nucleotide pyrophosphate phosphodiesterase 1)/PC-1 (plasma cell antigen-1) and IRS-1 (insulin receptor substrate-1) polymorphisms influencing insulin receptor activity on liver damage in non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of the metabolic syndrome, whose progression is associated with the severity of insulin resistance. PATIENTS AND METHODS: 702 patients with biopsy-proven NAFLD from Italy and the UK, and 310 healthy controls. The Lys121Gln ENPP1/PC-1 and the Gly972Arg IRS-1 polymorphisms were evaluated by restriction analysis. Fibrosis was evaluated according to Kleiner. Insulin signalling activity was evaluated by measuring phosphoAKT levels by western blotting in a subset of obese non-diabetic patients. RESULTS: The ENPP1 121Gln and IRS-1 972Arg polymorphisms were detected in 28.7% and 18.1% of patients and associated with increased body weight/dyslipidaemia and diabetes risk, respectively. The ENPP1 121Gln allele was significantly associated with increased prevalence of fibrosis stage >1 and >2, which was higher in subjects also positive for the 972Arg IRS-1 polymorphism. At multivariate analysis, the presence of the ENPP1 121Gln and IRS-1 972Arg polymorphisms was independently associated with fibrosis >1 (OR 1.55, 95% CI 1.24 to 1.97; and OR 1.57, 95% CI 1.12 to 2.23, respectively). Both polymorphisms were associated with a marked reduction of approximately 70% of AKT activation status, reflecting insulin resistance and disease severity, in obese patients with NAFLD. CONCLUSIONS: The ENPP1 121Gln and IRS-1 972Arg polymorphisms affecting insulin receptor activity predispose to liver damage and decrease hepatic insulin signalling in patients with NAFLD. Defective insulin signalling may play a causal role in the progression of liver damage in NAFLD.


Assuntos
Fígado Gorduroso/genética , Proteínas Substratos do Receptor de Insulina/genética , Diester Fosfórico Hidrolases/genética , Pirofosfatases/genética , Receptor de Insulina/metabolismo , Adulto , Fígado Gorduroso/metabolismo , Fígado Gorduroso/fisiopatologia , Feminino , Predisposição Genética para Doença , Humanos , Resistência à Insulina/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Índice de Gravidade de Doença , Transdução de Sinais/genética
4.
J Endocrinol Invest ; 32(8): 695-700, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19542757

RESUMO

BACKGROUND AND AIM: Non-alcoholic fatty liver disease (NAFLD) and polycystic ovary syndrome (PCOS) are both associated with insulin resistance.We assessed whether NAFLD is associated with impaired insulin sensitivity in PCOS women independently of age and total adiposity. SUBJECTS AND METHODS: We enrolled 14 young PCOS women with NAFLD, 14 women with PCOS alone and 14 healthy controls, who were matched for age, body mass index, and total body fat (by bio-impedance analyzer). NAFLD was diagnosed by the surrogate measure of abnormal serum alanine aminotransferase (ALT) concentrations (defined as ALT>19 U/l) after excluding other secondary causes of liver disease (alcohol, virus, and medications). Insulin sensitivity was measured by euglycemic hyperinsulinemic clamp. RESULTS: Insulin sensitivity was markedly decreased (p<0.001) in PCOS women with abnormal ALT levels, whereas it was similar between PCOS women with normal ALT levels andmatched healthy controls (8.3+/-2.5 vs 12.1+/-1.7 vs 13.2+/-1.8 mg/min x kg of fat-free mass, respectively). PCOS women with abnormal ALT levels also had higher plasma triglycerides and lower HDLcholesterol concentrations than those with PCOS alone. There was a strong inverse association between serum ALT levels and insulin sensitivity in the whole group of PCOS women (r=-0.59, p=0.0013). CONCLUSIONS: Abnormal serum ALT levels, as surrogate measure of NAFLD, are closely associated with impaired insulin sensitivity in young PCOS women in a manner that is independent from the contribution of age and total adiposity. Early recognition of NAFLD by radiological imaging tests in this group of young patients is warranted.


Assuntos
Alanina Transaminase/sangue , Resistência à Insulina/fisiologia , Síndrome do Ovário Policístico/enzimologia , Adolescente , Adulto , Fígado Gorduroso/sangue , Feminino , Humanos , Obesidade/complicações , Síndrome do Ovário Policístico/sangue , Estudos Retrospectivos
5.
Eur J Vasc Endovasc Surg ; 37(2): 160-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19013084

RESUMO

OBJECTIVES: To evaluate data in the New Zealand Thoracic Aortic Stent database to try and identify a scoring system that could predict 30-day mortality in patients undergoing stenting of the descending thoracic aorta (TEVAR). DESIGN: Retrospective analysis of the New Zealand thoracic aortic stent database between December 2001 and August 2007. MATERIALS AND METHODS: The 30-day mortality of the 122 patients is 7.38% (n=9). Risk factors were recorded based on the Society of Thoracic Surgeons (STS) risk score. Glasgow aneurysm score was calculated and the pathology being treated analysed. Univariate analysis was carried out. RESULTS: The mortality of three pathology groups was compared. 30-day mortality was 2.04% (n=1) in the elective aneurysm group, 17.95% (n=7) in the complicated Stanford type B dissection group, and 0% (n=0) in the trauma group. Thirty-day mortality is significantly higher in the dissection group compared with the elective aneurysm (p=0.02) and trauma (p=0.03) groups. The most frequent risk factors in the dissection group of patients were peripheral vascular disease, smoking and hypertension. Although percentage mortality is higher with increasing GAS, the results are not statistically significant (p=0.34). No independent risk factors were identified from the STS risk score data. CONCLUSION: No specific risk score system seems to be able to predict mortality in TEVAR patients.


Assuntos
Aorta Torácica/cirurgia , Doenças da Aorta/mortalidade , Doenças da Aorta/cirurgia , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Indicadores Básicos de Saúde , Stents , Dissecção Aórtica/mortalidade , Dissecção Aórtica/cirurgia , Aneurisma Infectado/mortalidade , Aneurisma Infectado/cirurgia , Aorta Torácica/lesões , Aorta Torácica/patologia , Aneurisma da Aorta Torácica/mortalidade , Aneurisma da Aorta Torácica/cirurgia , Doenças da Aorta/patologia , Mortalidade Hospitalar , Humanos , Nova Zelândia/epidemiologia , Valor Preditivo dos Testes , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
6.
Eur J Vasc Endovasc Surg ; 36(5): 530-4, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18805028

RESUMO

OBJECTIVES: Report the New Zealand national experience of endovascular repair of acute traumatic thoracic aortic injuries (TTAIs). DESIGN: Retrospective analysis of the New Zealand thoracic aortic stent database between December 2001 and December 2007. MATERIALS AND METHODS: Of the 134 patients on the database, 27 patients (20%) underwent endovascular repair of TTAI. Data collected included age, sex, cause of injury, details of the procedure, complications and mortality. RESULTS: Most patients were young, median age 20 (15-78), male (n=19, 70%), and involved in motor vehicle accidents (n=23, 85%). Median length of aorta stented was 117 mm (77-200 mm). Great vessel origins were covered intentionally in 23 (85%) patients, four (17%) requiring a hybrid procedure. Average procedure time was 98.3 min (35-180). Primary technical success was 96%, secondary technical success 100%. Endoleaks were observed in four (15%) patients, one requiring a second endovascular procedure. There were no conversions to open surgery. Procedure-related complications occurred in four (15%) patients. No patient developed cord injury. All cause mortality at 30 days is one (4%) and at discharge is two (7%) due to associated poly-trauma. CONCLUSION: Our results add further evidence of the safety of endovascular repair of thoracic aortic injury and compare favourably with those of other centres.


Assuntos
Aorta Torácica/cirurgia , Doenças da Aorta/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Stents , Ferimentos e Lesões/cirurgia , Doença Aguda , Adolescente , Adulto , Idoso , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/lesões , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/mortalidade , Implante de Prótese Vascular/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Desenho de Prótese , Falha de Prótese , Radiografia Intervencionista , Sistema de Registros , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Ferimentos e Lesões/diagnóstico por imagem , Ferimentos e Lesões/mortalidade
7.
Cardiovasc Intervent Radiol ; 30(1): 124-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17031725

RESUMO

We report the case of a 48-year-old man with neurofibromatosis presenting with sudden-onset abdominal pain, profound hypotension, and a drop in hemoglobin. CT scan demonstrated a massive hematoma within the right lobe of the liver with rupture into the peritoneal cavity. Angiography demonstrated diffuse abnormalities of the hepatic circulation with fusifom, ectatic, and stenotic segments. Acute extravasation from a peripheral branch of the right hepatic artery was identified and successfully embolized with subsequent hemodynamic stabilization of the patient. To the best of our knowledge this is the first case report of this kind in a patient with type I neurofibromatosis.


Assuntos
Embolização Terapêutica/métodos , Artéria Hepática/diagnóstico por imagem , Artéria Hepática/patologia , Neurofibromatoses/complicações , Doenças Vasculares/terapia , Dor Abdominal/etiologia , Evolução Fatal , Hematoma/diagnóstico , Hematoma/etiologia , Hemoglobinas/análise , Humanos , Hipotensão/etiologia , Fígado/diagnóstico por imagem , Circulação Hepática , Masculino , Pessoa de Meia-Idade , Ruptura Espontânea , Tomografia Computadorizada por Raios X/métodos , Doenças Vasculares/complicações , Doenças Vasculares/diagnóstico
8.
Cancer Gene Ther ; 13(7): 706-19, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16514421

RESUMO

To ensure the success of systemic gene therapy, it is critical to enhance the tumor specificity and activity of the promoter. In the current study, we determined that topoisomerase IIalpha promoter is selectively activated in breast cancer cells. An element containing an inverted CCAAT box (ICB) was shown to be responsible for the breast cancer specificity. When the ICB-harboring topoisomerase IIalpha minimal promoter was linked with an enhancer sequence from the cytomegalovirus immediate early gene promoter (CMV promoter), this composite promoter, CT90, exhibited activity comparable to or higher than the CMV promoter in breast cancer cells in vitro and in vivo, yet expresses much lower activity in normal cell lines and normal organs than the CMV promoter. A CT90-driven construct expressing BikDD, a potent proapoptotic gene, was shown to selectively kill breast cancer cells in vitro, and to suppress mammary tumor development in an animal model of intravenously administrated, liposome-delivered gene therapy. Expression of BikDD was readily detectable in the tumors but not in the normal organs (such as heart) of CT90-BikDD-treated animals. The results indicate that liposomal CT90-BikDD is an effective systemic breast cancer-targeting gene therapy.


Assuntos
Antígenos de Neoplasias/genética , Proteínas Reguladoras de Apoptose/genética , Neoplasias da Mama/terapia , DNA Topoisomerases Tipo II/genética , Proteínas de Ligação a DNA/genética , Terapia Genética , Proteínas de Membrana/genética , Mutação , Elementos de Resposta/genética , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Citomegalovirus/genética , Elementos Facilitadores Genéticos/genética , Feminino , Expressão Gênica , Vetores Genéticos , Humanos , Lipossomos , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Nus , Proteínas Mitocondriais , Neoplasias Experimentais
9.
Gut ; 55(6): 863-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16299026

RESUMO

BACKGROUND: The cytotoxic T lymphocyte antigen 4 (CTLA-4) gene encodes for a membrane bound (mCTLA-4) and a soluble (sCTLA-4) isoform, which are both involved in regulation of T cell function. The CTLA-4 +49A/G single nucleotide polymorphism (SNP) influences expression of mCTLA-4; +6230G/A SNP affects the production of sCTLA-4. AIM: To examine whether these functional SNPs influence the rate of rejection after liver transplantation. PATIENTS AND METHODS: Liver graft recipients (n = 483) were genotyped for both SNPs, and haplotypes were reconstructed. Association with rejection was tested by the log rank test using the Kaplan-Meier method with time to the first acute rejection episode as outcome. Multiple analysis of SNPs together with demographic factors was performed by Cox regression. RESULTS: Three haplotypes were observed in the cohort: +49A/+6230A, +49A/+6230G, and +49G/+6230G. The +49A/+6230G haplotype was significantly and dose dependently associated with acute rejection (p = 0.01). Of the demographic factors tested, only underlying liver disease was significantly associated with rejection. Adjusted for underlying liver disease, each additional +49A/+6230G haplotype allele resulted in a significantly higher risk of acute rejection (risk ratio 1.34 (95% confidence interval 1.04-1.72); p = 0.02). Patients who lacked this haplotype had the lowest, carriers an intermediate, and homozygotes the highest risk of acute rejection. CONCLUSION: The CTLA-4 +49A/+6230G haplotype, which encodes for normal mCTLA-4 expression but reduced sCTLA-4 production, is a co-dominant risk allele for acute rejection after clinical liver transplantation. This implies that even under immunosuppression, CTLA-4 is critically involved in the regulation of the human immune response to allogeneic grafts.


Assuntos
Antígenos de Diferenciação/genética , Rejeição de Enxerto/genética , Transplante de Fígado , Polimorfismo Genético , Doença Aguda , Antígenos CD , Antígeno CTLA-4 , Feminino , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Estudos Retrospectivos
10.
Gut ; 54(8): 1174-9, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16009691

RESUMO

INTRODUCTION: Alcoholic hepatitis is associated with a high short term mortality. We aimed to identify those factors associated with mortality and define a simple score which would predict outcome in our population. METHODS: We identified 241 patients with alcoholic hepatitis. Clinical and laboratory data were recorded on the day of admission (day 1) and on days 6-9. Stepwise logistic regression was used to identify variables related to outcome at 28 days and 84 days after admission. These variables were included in the Glasgow alcoholic hepatitis score (GAHS) and its ability to predict outcome assessed. The GAHS was validated in a separate dataset of 195 patients. RESULTS: The GAHS was derived from five variables independently associated with outcome: age (p = 0.001) and, from day 1 results, serum bilirubin (p<0.001), blood urea (p = 0.019) and, from day 6-9 results, serum bilirubin (p<0.001), prothrombin time (p = 0.002), and peripheral blood white blood cell count (p = 0.001). The GAHS on day 1 had an overall accuracy of 81% when predicting 28 day outcome. In contrast, the modified discriminant function had an overall accuracy of 49%. Similar results were found using information at 6-9 days and when predicting 84 day outcome. The accuracy of the GAHS was confirmed by the validation study of 195 patients The GAHS was equally accurate irrespective of the use of the international normalised ratio or prothrombin time ratio, or if the diagnosis of alcoholic hepatitis was biopsy proven or on the basis of clinical assessment. CONCLUSIONS: Using variables associated with mortality we have derived and validated an accurate scoring system to assess outcome in alcoholic hepatitis. This score was able to identify patients at greatest risk of death throughout their admission.


Assuntos
Hepatite Alcoólica/mortalidade , Bilirrubina/sangue , Contagem de Células Sanguíneas , Hepatite Alcoólica/sangue , Hepatite Alcoólica/fisiopatologia , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Tempo de Protrombina , Curva ROC , Reprodutibilidade dos Testes , Fatores de Risco , Índice de Gravidade de Doença , Análise de Sobrevida , Ureia/sangue
11.
Biochimie ; 87(5): 437-43, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15820750

RESUMO

Phosphatidic acid phosphohydrolase-1 (PAP-1) activity is reversibly inhibited by fatty acids and their acyl-CoA esters and it appears paradoxical that these effectors have been reported to increase the liver's esterification capacity by translocating the rate-limiting enzyme PAP-1 from cytosol to the endoplasmic reticulum. Therefore, we have examined the effect of oleate, oleoyl-CoA, and spermine on the activation and translocation of PAP-1 of rat liver. PAP-1 activity is directly inhibited by oleic acid and oleoyl-CoA ester in an allosteric manner, resulting in the formation of inactive PAP-1-fatty acid (or -acyl-CoA) complex, even in the absence of any subcellular structures. Such association/aggregation of PAP-1 can be easily collected by centrifugation and may explain the apparent translocation phenomenon of this enzyme to a particular structure in the presence of fatty acids or acyl-CoA esters as reported in many works. Indeed, incubation of cytosol fraction alone with oleate or oleoyl-CoA at 37 degrees C, followed by centrifugation, induces a significant increase (sevenfold) in PAP-1 activity in the pellet fraction. This displacement is accompanied by an increase in the specific activity of PAP-1 in the pellet fraction. Spermine is less effective than oleate in inducing the displacement of PAP-1 activity from cytosol to the pellet fraction in the absence of any membrane structures. This apparent translocation of PAP-1 is also promoted when homogenate fraction was incubated with oleate prior to the preparation of cytosol and microsomal fraction. Thus, many of the announced factors, including fatty acids, would promote the in vitro association/aggregation of PAP-1 enzyme rather than its translocation, and therefore, re-evaluation of the reported effects on PAP-1 translocation phenomenon is required. It is proposed that fatty acids and their esters would favour beta-oxidation over esterification by promoting the forming of inactive associated PAP-1 in situations such as starvation and metabolic stress in which there is an increased supply of fatty acids to the liver.


Assuntos
Acil Coenzima A/farmacologia , Ativação Enzimática/efeitos dos fármacos , Fígado/enzimologia , Ácido Oleico/farmacologia , Fosfatidato Fosfatase/antagonistas & inibidores , Animais , Citosol/enzimologia , Retículo Endoplasmático/enzimologia , Ésteres/farmacologia , Fígado/efeitos dos fármacos , Masculino , Oxirredução , Proteínas Associadas a Pancreatite , Transporte Proteico , Ratos , Ratos Wistar , Espermina/farmacologia , Frações Subcelulares/enzimologia
12.
Best Pract Res Clin Gastroenterol ; 16(5): 663-78, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12406438

RESUMO

Understanding the pathogenesis of non-alcoholic steatohepatitis has recently assumed great importance with the recognition that it has the potential to progress to fibrosis and cirrhosis. The 'two-hit' model of pathogenesis was proposed in 1998, with the first 'hit' - steatosis - increasing the sensitivity of the liver to the second 'hits' mediating liver injury. The main aim of this chapter is to review this model in the light of studies that have been published over the subsequent 4 years. Particular attention will be focused on the role of insulin resistance and recent advances in our understanding of the basic cellular mechanisms linking obesity and insulin resistance. Based on this information I will propose a modification of the two-hit model that places more emphasis on the role of free fatty acids. This model will provide the basis for further research and enable the rational design of treatment strategies.


Assuntos
Fígado Gorduroso/patologia , Resistência à Insulina/fisiologia , Citocinas/metabolismo , Progressão da Doença , Suscetibilidade a Doenças , Ácidos Graxos não Esterificados/metabolismo , Fígado Gorduroso/metabolismo , Fígado Gorduroso/fisiopatologia , Humanos , Peroxidação de Lipídeos , Obesidade/complicações , Obesidade/metabolismo , Obesidade/fisiopatologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Risco , Fator de Necrose Tumoral alfa/metabolismo
13.
Dig Dis Sci ; 46(7): 1520-5, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11478505

RESUMO

Interleukin-10 (IL-10) has a key role in regulating mucosal inflammation. The role of functional polymorphisms at positions -627 and -1117 in the IL-10 gene as candidate susceptibility loci in inflammatory bowel disease and their importance in determining disease extent were evaluated in 159 patients with ulcerative colitis (83 left-sided; 76 extensive), 90 patients with Crohn's disease (22 small bowel; 29 large bowel; 39 both), and 227 controls. Genotyping was performed either by PCR-RFLP assays (-627 site) or SSCP analysis (-1117 site). An excess of -627A allele was observed in patients with left-sided colitis (52%) compared with controls (33%; P = 0.004) suggesting that IL-10 may influence the extent of the disease. These results were not replicated in a newly recruited group (N = 100) of patients with UC. We conclude that polymorphisms at -627 and -1117 sites in the IL-10 gene do not contribute to the susceptibility to IBD or determining the extent of the disease in our population.


Assuntos
Doenças Inflamatórias Intestinais/genética , Interleucina-10/genética , Colite Ulcerativa/genética , Doença de Crohn/genética , Predisposição Genética para Doença , Humanos , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Polimorfismo Conformacional de Fita Simples
14.
Gut ; 49(2): 288-94, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11454808

RESUMO

BACKGROUND AND AIMS: Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown aetiology. Abnormalities in immune regulation and genetic associations suggest that PSC is an immune mediated disease. Several polymorphisms within the tumour necrosis factor alpha (TNF-alpha) and interleukin 10 (IL-10) promoter genes have been described which influence expression of these cytokines. This study examines the possible association between polymorphisms at the -308 and -627 positions in the TNF-alpha and IL-10 promoter genes, respectively, and susceptibility to PSC. METHODS: TNF-alpha -308 genotypes were studied by polymerase chain reaction (PCR) in 160 PSC patients from Norway and the UK compared with 145 ethnically matched controls. IL-10 -627 genotypes were studied by PCR in 90 PSC patients compared with 84 ethnically matched controls. RESULTS: A total of 16% of Norwegian PSC patients and 12% of British PSC patients were homozygous for the TNF2 allele compared with 3% and 6% of respective controls. The TNF2 allele was present in 60% of PSC patients versus 30% of controls (OR(combined data)=3.2 (95% confidence intervals (CI) 1.8--4.5); p(corr)=10(-5)). The association between the TNF2 allele and susceptibility to PSC was independent of the presence of concurrent inflammatory bowel disease (IBD) in the PSC patients; 61% of PSC patients without IBD had TNF2 compared with 30% of controls (OR(combined data)=3.2 (95% CI 1.2--9.0); p(corr)=0.006 ). There was no difference in the -627 IL-10 polymorphism distributions between patients and controls in either population. The increase in TNF2 allele in PSC patients only occurs in the presence of DRB1*0301 (DR3) and B8. In the combined population data, DRB1*0301 showed a stronger association with susceptibility to PSC than both the TNF2 and B8 alleles (OR(combined data)=3.8, p(corr)=10(-6) v OR(combined data)=3.2, p(corr)=10(-5) v OR(combined data )=3.41, p(corr)=10(-4), respectively). CONCLUSIONS: This study identified a significant association between possession of the TNF2 allele, a G-->A substitution at position -308 in the TNF-alpha promoter, and susceptibility to PSC. This association was secondary to the association of PSC with the A1-B8-DRB1*0301-DQA1*0501-DQB1*0201 haplotype. No association was found between the IL-10 -627 promoter polymorphism and PSC.


Assuntos
Colangite Esclerosante/genética , Interleucina-10/genética , Regiões Promotoras Genéticas/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Alelos , Estudos de Casos e Controles , Colangite Esclerosante/complicações , Colangite Esclerosante/imunologia , Intervalos de Confiança , Feminino , Genótipo , Teste de Histocompatibilidade , Homozigoto , Humanos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
16.
Genes Immun ; 2(1): 44-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11294568

RESUMO

Interleukin-4 (IL-4) is an important cytokine in mucosal immunity and plays a critical role in the development of colitis in T-alpha cell receptor mutant mice. Functionally significant polymorphisms have been described in the genes encoding IL-4 and IL-4 receptor. To examine the role of these polymorphisms in disease susceptibility 98 patients with ulcerative colitis, 86 patients with Crohn's disease and 321 healthy controls were genotyped for polymorphisms at position -34 in the IL-4 gene and codon 576 in the IL-4 receptor gene. Thirty-two percent of patients with Crohn's disease carried one or two copies of the variant allele for IL-4 compared with 16% of the controls (P = 0.002). Forty-one percent of patients with Crohn's disease carried one or two copies of the variant IL-4 receptor allele compared with 31% of the controls (P = 0.09). Fifteen percent of patients with Crohn's disease carried combination of both (IL-4 and IL-4 receptor) variant alleles compared with 4% of the controls (P = 0.005). Association with alleles resulting in high IL-4 transcription and enhanced signalling activity suggests that IL-4 may have a role in the pathogenesis of Crohn's disease.


Assuntos
Doença de Crohn/genética , Interleucina-4/genética , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina-4/genética , Sequência de Bases , Doença de Crohn/epidemiologia , Doença de Crohn/etnologia , Primers do DNA , Predisposição Genética para Doença , Humanos , Reino Unido/epidemiologia
17.
Gut ; 46(4): 540-5, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10716685

RESUMO

BACKGROUND: The factors determining why less than 10% of heavy drinkers develop advanced alcoholic liver disease (ALD) remain elusive, although genetic factors may be important. Interleukin 10 (IL-10) is an important cytokine with anti-inflammatory, anti-immune, and antifibrotic functions. Several polymorphisms have been identified in the IL-10 promoter and recent evidence suggests that some of these may have functional effects on IL-10 secretion. AIMS: To test the hypothesis that IL-10 promoter region polymorphisms are associated with susceptibility to ALD. METHODS: The allele frequencies for the two single base pair substitutions at positions -627 (C-->A) and -1117 (A-->G) in the IL-10 promoter were determined in 287 heavy drinkers with biopsy proved advanced ALD, 107 heavy drinkers with no evidence of liver disease or steatosis only on biopsy, and 227 local healthy volunteers. RESULTS: At position -627, 50% of patients with advanced ALD had a least one A allele compared with 33% of controls (p<0.0001) and 34% of drinkers with no or mild disease (p=0.017). At position -1117, the slight excess of the A allele in drinkers with advanced disease was because of linkage disequilibrium between the A alleles at the two sites. CONCLUSIONS: Among heavy drinkers, possession of the A allele at position -627 in the IL-10 promoter is associated with an increased risk of advanced liver disease. This is consistent with recent functional data that the -627*A allele is associated with low IL-10 expression which will favour inflammatory, immune mediated, and profibrotic mechanisms of alcohol related liver injury.


Assuntos
Predisposição Genética para Doença , Interleucina-10/genética , Cirrose Hepática Alcoólica/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Alelos , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Razão de Chances
18.
J Hepatol ; 32(3): 465-72, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10735617

RESUMO

BACKGROUND/AIMS: The signal cascades involved in the activation of hepatic stellate cells (HSC) are largely unknown. Factors initiating activation include tumour necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta, endothelin, and oxidative stress. In other cell types some of these have been reported to stimulate p38 mitogen-activated protein (MAP) kinase and c-Jun N-terminal kinase (JNK). We have therefore investigated the role of these kinases in HSC activation. METHODS: HSC were isolated from male Wistar rats. Quiescent experiments were performed on day 2 HSC and transformed experiments on day 15 passage 1 HSC. Kinase activities were determined by immunoprecipitation and phosphorylation of specific substrate proteins and alpha-smooth muscle actin (SMA) expression by immunoblotting. RESULTS: The constitutive activity of p38 MAP kinase was higher in transformed versus quiescent cells. In quiescent cells TNFalpha stimulated p38 MAP kinase and JNK activities 12- and 4-fold respectively and this was halved by 2-mercaptoethanol, an indirect antioxidant. Endothelin-1 activated both kinases in quiescent cells via the endothelin-B receptor, while TGFbeta had no effect. Both 2-mercaptoethanol and a p38 inhibitor (SB202190) inhibited alpha-SMA expression by day 5 cells. CONCLUSIONS: The activation of p38 MAP kinase and JNK by TNFalpha and endothelin, together with the inhibition of this activation by 2-mercaptoethanol, provides indirect evidence supporting their role in HSC transformation. Direct evidence for a role for p38 MAP kinase is provided by the observations that its constitutive activity is higher in transformed versus quiescent cells and that its inhibitor reduces HSC activation in culture as assessed by alpha-SMA expression.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/fisiologia , Fígado/fisiologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Actinas/metabolismo , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Linhagem Celular Transformada , Células Cultivadas , Endotelina-1/farmacologia , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno , Fígado/citologia , Fígado/enzimologia , Masculino , Mercaptoetanol/farmacologia , Músculo Liso/metabolismo , Piridinas/farmacologia , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno
19.
Gut ; 44(5): 731-5, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10205214

RESUMO

BACKGROUND: The long term outcome of drug related liver disease is unknown. AIMS: To study the natural history of histologically proved drug induced hepatotoxicity. METHODS: 110 patients with liver biopsies coded either as drug induced liver disease or hepatitis/cholestasis of unknown aetiology were identified from hospital records 1978-1996. Review of case notes and histology identified 44 patients with definite drug induced hepatotoxicity. Forty surviving patients were invited to attend a follow up clinic. History, examination, full liver screen, and isotope and ultrasound liver scans were repeated in all patients. Repeat liver biopsies were offered to patients with abnormal liver tests. RESULTS: Presentation at index biopsy was jaundice in 24 patients, abnormal liver tests in 17, and hepatic failure in three. Antibiotics (n=13) and non-steroidal anti-inflammatory drugs (n=11) were the most common drugs implicated. Initial histology showed acute hepatitis in six, chronic hepatitis in 20, and cholestasis in 18. At 1-19 years (median 5 years) follow up, 13/33 (39%) patients had persistent significant abnormalities in their liver blood tests and/or scans. Three of the five repeat liver biopsies performed showed significant abnormalities. Factors predicting persistence or development of chronic liver disease were fibrosis and continued exposure to the drug. CONCLUSIONS: Drugs should be considered in the differential diagnosis of abnormal liver function and/or histology, as failure to withdraw the offending drug is associated with a high risk of persistent liver damage.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Adolescente , Adulto , Idoso , Antibacterianos/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Biópsia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/etiologia , Feminino , Seguimentos , Humanos , Icterícia/induzido quimicamente , Hepatopatias/patologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Prognóstico
20.
J Hepatol ; 30(2): 232-6, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10068101

RESUMO

BACKGROUND/AIMS: The incidence of primary biliary cirrhosis (PBC) is increased in the close relatives of patients, suggesting that genetic factors play a role in disease susceptibility. Decreased in vitro production of tumour necrosis factor (TNF)-alpha has been reported in PBC patients, suggesting a potential aetiological role for this cytokine. The aim of this study was to examine two biallelic polymorphisms in the promoter region of the TNF-alpha gene, which may play a role in the control of TNF-alpha secretion, as candidate susceptibility loci in PBC. METHODS: The polymorphisms at positions -238 and -308 in the TNF-alpha promoter region were analysed by polymerase chain reaction in 168 unrelated PBC patients and 145 local unrelated, geographically matched normal individuals. All PBC subjects were also genotyped for HLA DR8, a previously identified susceptibility locus in PBC. RESULTS: The -308 TNF1/TNF1 genotype was seen in a similar proportion of PBC patients (66%) and controls (60%). However, this genotype was found significantly more frequently in the 95 PBC patients with more advanced disease (histological stage III/IV) (77%) than in either controls (p<0.01, OR = 2.2 [1.2-4.0]) or the PBC patients with earlier disease (38/73 (52%), p = 0.001 OR 3.1 [1.6-5.9]). Linkage between TNF -308 and HLA DR8 was not seen. No association was found between PBC and the biallelic -238 TNF-alpha polymorphism, either in the whole PBC population or the histological Stage III/IV subgroup. CONCLUSIONS: Our study provides no evidence for involvement of the TNF-alpha -308 or -238 promoter polymorphisms in genetic predisposition to PBC. However, the significantly increased frequency of the -308 TNF1/TNF1 genotype seen in 95 patients with more advanced disease raises the possibility that this allele may be linked to disease progression rather than susceptibility. The finding of different allele frequencies in PBC patients in different disease subgroups emphasises the importance of clinical phenotype/casemix in the design of disease association studies.


Assuntos
Cirrose Hepática Biliar/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética , Fator de Necrose Tumoral alfa/genética , Idoso , Alelos , Progressão da Doença , Frequência do Gene , Genótipo , Antígenos HLA-DR/análise , Subtipos Sorológicos de HLA-DR , Humanos , Cirrose Hepática Biliar/imunologia , Cirrose Hepática Biliar/fisiopatologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
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