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1.
J Viral Hepat ; 9(4): 288-94, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12081606

RESUMO

Heavy alcohol consumption has been reported to negatively affect the outcome of interferon therapy. We studied the impact of lifetime alcohol consumption in patients with chronic hepatitis C treated with interferon after 6 months of alcohol withdrawal. Alcohol intake was measured when patients with chronic hepatitis C were referred to us for the first time, and from that moment complete abstinence was recommended. After 6 months of abstinence, 150 patients with persistent elevated serum alanine aminotransferase (ALT) have been treated with interferon (IFN)-alpha, 3 or 6 microU three times per week for 12 months. Univariate and multivariate analysis were performed to identify the predictors of treatment response. Carbohydrate-deficient transferrin was employed to assess alcoholic abstinence. The sustained response rate felt from 33% in nondrinkers to 20% of mild-drinkers and to only 9% in heavy drinkers. Drinker patients showed a relapse rate twice as high as that of nondrinkers. According to the multivariate analysis, the strongest independent predictors of nonresponse were genotype 1b infection, age of the patients and their lifetime alcohol intake. Carbohydrate-deficient transferrin detected at baseline, at 3 months of therapy and at the end of follow-up gave a positive result only in eight determinations (1.77%), confirming the compliance of patients to our recommendation of alcohol abstinence. Lifetime alcohol consumption has a strong negative effect on the outcome of interferon treatment, mainly in heavy drinkers. A 6-month period of abstinence may not be sufficient to offset this negative effect on treatment outcome.


Assuntos
Consumo de Bebidas Alcoólicas , Antivirais/uso terapêutico , Hepatite C Crônica/terapia , Interferon-alfa/uso terapêutico , Adulto , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Resultado do Tratamento
2.
Exp Cell Res ; 268(2): 139-49, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11478840

RESUMO

Autophagy is a major catabolic process allowing the renewal of intracellular organelles by which cells maintain their homeostasis. We have previously shown that autophagy is controlled by two transduction pathways mediated by a heterotrimeric Gi3 protein and phosphatidylinositol 3-kinase activities in the human colon cancer cell line HT-29. Here, we show that 3-methyladenine, an inhibitor of autophagy, increases the sensitivity of HT-29 cells to apoptosis induced by sulindac sulfide, a nonsteroidal anti-inflammatory drug which inhibits the cyclooxygenases. Similarly, HT-29 cells overexpressing a GTPase-deficient mutant of the G(alpha i3) protein (Q204L), which have a low rate of autophagy, were more sensitive to sulindac sulfide-induced apoptosis than parental HT-29 cells. In both cell populations we did not observe differences in the expression patterns of COX-2, Bcl-2, Bcl(XL), Bax, and Akt/PKB activity. However, the rate of cytochrome c release was higher in Q204L-overexpressing cells than in HT-29 cells. These results suggest that autophagy could retard apoptosis in colon cancer cells by sequestering mitochondrial death-promoting factors such as cytochrome c.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Apoptose/fisiologia , Autofagia/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Proteínas Serina-Treonina Quinases , Sulindaco/farmacologia , Adenina/análogos & derivados , Adenina/farmacologia , Caspases/metabolismo , Ciclo-Oxigenase 2 , Grupo dos Citocromos c/metabolismo , Relação Dose-Resposta a Droga , Antagonismo de Drogas , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Humanos , Isoenzimas/biossíntese , Proteínas de Membrana , Prostaglandina-Endoperóxido Sintases/biossíntese , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas c-akt , Sulindaco/análogos & derivados , Células Tumorais Cultivadas
3.
J Biol Chem ; 276(38): 35243-6, 2001 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-11477064

RESUMO

The tumor suppressor PTEN is a dual protein and phosphoinositide phosphatase that negatively controls the phosphatidylinositol (PI) 3-kinase/protein kinase B (Akt/PKB) signaling pathway. Interleukin-13 via the activation of the class I PI 3-kinase has been shown to inhibit the macroautophagic pathway in the human colon cancer HT-29 cells. Here we demonstrate that the wild-type PTEN is expressed in this cell line. Its overexpression directed by an inducible promoter counteracts the interleukin-13 down-regulation of macroautophagy. This effect was dependent upon the phosphoinositide phosphatase activity of PTEN as determined by using the mutant G129E, which has only protein phosphatase activity. The role of Akt/PKB in the signaling control of interleukin-13-dependent macroautophagy was investigated by expressing a constitutively active form of the kinase ((Myr)PKB). Under these conditions a dramatic inhibition of macroautophagy was observed. By contrast a high rate of autophagy was observed in cells expressing a dominant negative form of PKB. These data demonstrate that the signaling control of macroautophagy overlaps with the well known PI 3-kinase/PKB survival pathway and that the loss of PTEN function in cancer cells inhibits a major catabolic pathway.


Assuntos
Autofagia , Genes Supressores de Tumor , Inibidores de Fosfoinositídeo-3 Quinase , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Supressoras de Tumor , Sequência de Bases , Divisão Celular , Primers do DNA , Ativação Enzimática , Células HT29 , Humanos , Interleucina-13/fisiologia , PTEN Fosfo-Hidrolase , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Regulação para Cima
5.
Hepatology ; 31(4): 878-84, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10733543

RESUMO

Acetaldehyde and malonildialdehyde can form hybrid protein adducts, named MAA adducts that have strong immunogenic properties. The formation of MAA adducts in the liver of chronic alcohol-fed rats is associated with the development of circulating antibodies that specifically recognized these adducts. The aim of this study was to examine whether MAA adducts might participate in the immune response associated with human alcohol-induced liver disease. Circulating antibodies against MAA adducts were evaluated in 50 patients with alcohol-induced hepatitis or cirrhosis, in 40 patients with non-alcohol-induced liver disease, in 15 heavy drinkers without liver damage and in 40 healthy controls by enzyme-linked immunosorbent assays (ELISA). Immunoglobulin G (IgG) reacting with MAA-modified proteins were significantly increased in the patients with alcohol-induced cirrhosis or hepatitis. The individual levels of anti-MAA IgG in those patients were associated with the severity of liver damage. Anti-MAA antibodies were also positively correlated with the levels of IgG recognizing epitopes generated by acetaldehyde and malonildialdehyde. However, competitive inhibition experiments indicated that the anti-MAA antibodies were unrelated to those against acetaldehyde- or malonildialdehyde-derived antigens and mainly recognized a specific, cyclic MAA epitope. Some degree of immune reactivity towards MAA adducts was also observed in patients with non-alcohol-induced liver injury. However, competitive ELISA showed that the antigens recognized by these sera were not the cyclic MAA adducts. Altogether, these results showed the formation of MAA antigens during alcohol-induced liver disease and suggest their possible contribution to the development of immunologic reactions associated with alcohol-related liver damage.


Assuntos
Acetaldeído/imunologia , Anticorpos/sangue , Hepatopatias Alcoólicas/imunologia , Malondialdeído/imunologia , Adulto , Idoso , Especificidade de Anticorpos , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Feminino , Hepatite Alcoólica/imunologia , Humanos , Imunoglobulina G/sangue , Cirrose Hepática Alcoólica/imunologia , Masculino , Pessoa de Meia-Idade
6.
Mol Pharmacol ; 55(2): 223-33, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9927612

RESUMO

Autoantibodies against soluble liver enzymes have been reported among alcoholics, but the targets of self-reactivity toward membrane proteins of the liver have not been characterized. Previously, among alcoholics, we found antibodies against ethanol-derived radical protein adducts that are dependent on cytochrome P-4502E1 (CYP2E1) for their formation. To further investigate autoantibodies against cytochrome P-450s during alcohol abuse, sera of rats chronically treated with ethanol in the total enteral nutrition model and sera from alcoholics with or without alcohol liver disease and from control subjects were analyzed by enzyme-linked immunosorbent assay and Western blotting for the presence of IgG against rat and human CYP2E1, rat CYP3A1, and human CYP3A4. A time-dependent appearance of IgG against rat CYP3A1 and CYP2E1 was evident during chronic ethanol feeding of rats. Anti-CYP2E1 reactivity showed positive correlation with the levels of hepatic CYP2E1 and was inhibited by the CYP2E1 transcriptional inhibitor chlormethiazole. Screening of the human sera by enzyme-linked immunosorbent assay revealed reactivity against CYP3A4 and CYP2E1 in about 20 to 30% and 10 to 20% of the alcoholic sera, respectively. No difference were noted between sera from alcoholics with or without hepatitis C virus infection, and only very little reactivity was seen in sera from control subjects. Western blotting analysis revealed anti-human CYP2E1 reactivity in 8 of 85 alcoholic sera and 3 of 58 control sera, whereas anti-CYP3A4 reactivity was detected in 18 of 85 alcoholic sera and 4 of 58 control sera, which were different from the sera reactive with CYP2E1. Immunoblot reactivity of CYP3A4-positive alcoholic sera was found against glutathione-S-transferase fusion proteins containing truncated forms of CYP3A4, and such sera were also able to immunoprecipitate in vitro translated CYP3A4. Seven of eight sera showed reactivity toward domains C-terminal of position Ser281, and 1 of 8 sera recognized autoepitopes within the region Thr207-Ser281. These findings indicate that alcoholics develop autoantibodies against CYP2E1 and CYP3A4 that the CYP3A4 C-terminal domain is a target for the autoantibody reactions among a subset of alcoholics. The novel finding of CYP3A4 autoantibodies and their significant expression among alcoholics warrants further investigation. Attention should be given to immune toxicity associated with CYP3A4 autoantibodies and cases of alcohol abuse that are accompanied by exposure to drugs and substances that are CYP3A substrates.


Assuntos
Alcoolismo/imunologia , Hidrocarboneto de Aril Hidroxilases , Autoanticorpos/imunologia , Citocromo P-450 CYP2E1/imunologia , Sistema Enzimático do Citocromo P-450/imunologia , Oxirredutases N-Desmetilantes/imunologia , Adulto , Idoso , Alcoolismo/epidemiologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Autoanticorpos/análise , Depressores do Sistema Nervoso Central/farmacologia , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/genética , Etanol/farmacologia , Feminino , Humanos , Soros Imunes/imunologia , Itália/epidemiologia , Masculino , Microssomos Hepáticos/imunologia , Pessoa de Meia-Idade , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/imunologia , Dados de Sequência Molecular , Plasmídeos/genética , Coelhos , Ratos , Ratos Wistar , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Deleção de Sequência , Homologia de Sequência de Aminoácidos , Suécia/epidemiologia
7.
Alcohol Alcohol ; 34(6): 873-81, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10659723

RESUMO

The observational evaluation of alcoholics' treatments requires a combined analysis of alcoholic behaviour during treatment and of adherence to therapeutic programmes. The application of survival analysis techniques in this setting has been explored in this study. Two hundred and seventy alcoholics admitted to 15 Italian treatment units in a 1-year period were followed-up for 2 years, recording date and length of every recurrence episode and of definitive or transitory interruption of the planned treatment. An extensive use of several survival analysis techniques was made. The length of time between the start of the treatment and the first episode of relapse did not give a reliable measure of frequency of failures. Conversely, the length of time between the start of treatment and withdrawal appeared to be unbiased. The cumulative proportions of treatment-compliant patients (and the corresponding 95% confidence intervals) were 71% (66-76%), 63% (57-69%) and 53% (47-60%) after 6 months, 1 year and 2 years respectively from the start of treatment. Cumulative abstinence duration before withdrawal was significantly and positively associated with the risk of first, of definitive, and of every episode of treatment interruption. This first application of survival analysis techniques to the combined study of alcoholic behaviour and of adherence to treatment can improve our knowledge of treatment evaluation. Our results suggest that compliance to treatment is an objective and versatile outcome measure. Long-term follow-up studies aimed to elucidate the determinants of withdrawal should be performed.


Assuntos
Alcoolismo/reabilitação , Terapia Comportamental , Alcoolismo/epidemiologia , Terapia Combinada , Seguimentos , Humanos , Itália , Avaliação de Processos e Resultados em Cuidados de Saúde , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Recidiva , Análise de Sobrevida , Temperança
8.
Addiction ; 94(10): 1551-73, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10790907

RESUMO

OBJECTIVE: To compare the strength of the evidence provided by the epidemiological literature on the association between alcohol consumption and the risk of six cancers (oral cavity, oesophagus, colorectum, liver, larynx, breast), hypertension, cerebrovascular diseases, gastric and duodenal ulcer, liver cirrhosis and other chronic liver diseases, pancreatitis and injures and adverse effects. METHODS: A search of the epidemiological literature from 1966 to 1998 was performed by several bibliographic databases. Meta-regression models were fitted considering fixed and random models and linear and non-linear effects of alcohol intake on the risk of each condition. The effects of some characteristics of the studies including an index of their quality were considered as putative sources of heterogeneity of the estimates. Publication bias was also investigated by asymmetry of funnel plots. RESULTS: Of the 397 initially reviewed studies, 200 were selected for meta-analysis. Since qualitative characteristics of the studies were often significant sources of heterogeneity among them, the estimates of the pooled dose-response slopes were based only on the 123 studies with higher quality score and/or reporting adjusted estimates of relative risks. Higher alcohol-related risks were found for liver cirrhosis, neoplasms of the upper respiratory and digestive tracts, haemorrhagic stroke and injuries and adverse effects. Weaker but significant associations were found for colorectum, liver and breast cancers, essential hypertension and chronic pancreatitis. For all these conditions, low intakes, corresponding to daily consumption of two drinks or two glasses of wine (25 g/day), have shown significant risks. Ischaemic stroke and gastric and duodenal ulcer seem independent of alcohol intake. The area in which the study was performed, the study's design and the outcome variable differently affected the slopes. CONCLUSIONS: The small number of sufficiently reliable studies, the strong indications of heterogeneity across them and the suspicion of publication bias suggest that there is a great need for well-conducted epidemiological studies performed in several countries, to examine the dose-response relationship between alcohol intake and the risk of several alcohol-related conditions, as well as the role of drinking pattern in determining the risk.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Transtornos Relacionados ao Uso de Álcool/complicações , Consumo de Bebidas Alcoólicas/epidemiologia , Transtornos Relacionados ao Uso de Álcool/epidemiologia , Relação Dose-Resposta a Droga , Humanos , Neoplasias/induzido quimicamente , Fatores de Risco
9.
Eur J Epidemiol ; 14(5): 447-56, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9744676

RESUMO

Although alcohol intake and hepatitis B and C virus (HBV and HCV) infections are the major determinants of liver cirrhosis (LC) in western countries, the joint effect of these factors on LC risk has not yet been adequately studied. Data from three case-control studies performed in Italy were used. Cases were 462 cirrhotic patients admitted to Hospitals for liver decompensation. Controls were 651 inpatients admitted for acute diseases unrelated to alcohol. Alcohol consumption was expressed as lifetime daily alcohol intake (LDAI). Three approaches were used to explore the interaction structure. The Breslow and Storer parametric family of relative risk functions showed that an intermediate structure of interaction from additive to multiplicative was the most adequate one. The Rothman synergism index showed that the interaction structure between LDAI and viral status differed significantly from the additive model in particular for high levels of alcohol intake. When multiple regression additive and multiplicative models were compared after adjustment for the known confounding variables. a trend of the interaction structure towards the multiplicative model was observed at increasing levels of consumption. Better methods are needed for assessing mixed interaction structures in conditions characterized by multifactorial etiologies like cirrhosis of the liver.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Cirrose Hepática/epidemiologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Análise de Regressão , Fatores de Risco
10.
J Hepatol ; 28(4): 608-14, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9566829

RESUMO

BACKGROUNDS/AIMS: Knowledge of the proportion of liver cirrhosis attributable to the main risk factors is largely based on methodologically questionable clinical reports. METHODS: The proportion of newly diagnosed cases of symptomatic liver cirrhosis attributable to known risk factors was estimated by a case-control study performed during 1989-1996 in 23 medical divisions of several hospitals distributed throughout Italy. Cases were 462 inpatients with cirrhosis admitted for the first time for liver decompensation. Controls were 651 patients admitted during the same period and to the same hospitals as the cases, for acute diseases unrelated to alcohol and virus infection. The proportion of symptomatic liver cirrhosis cases due to alcohol intake and hepatitis B and C viruses and the combination of these was expressed as the population attributable risk. RESULTS: Attributable risks were 67.9% (95% confidence interval (CI): 53.8-79.4) for alcohol, 40.1% (95% CI: 35.3-45.2) for hepatitis C virus and 4.4% (95% CI: 2.5-7.6) for hepatitis B virus. The three factors together explained 98.1% (95% CI: 81.6-99.6) of cases in men and 67.0% (95% CI: 50.4-85.8) in women. CONCLUSIONS: Alcohol is the risk factor with the highest impact on symptomatic liver cirrhosis risk in Italy. From a public health viewpoint, with the elimination of the well-known risk factors (particularly alcohol and hepatitis C virus), liver cirrhosis should become a rare disease.


Assuntos
Cirrose Hepática Alcoólica/epidemiologia , Cirrose Hepática/etiologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Hepatite B/complicações , Hepatite C/complicações , Humanos , Itália/epidemiologia , Cirrose Hepática/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
11.
Hepatology ; 27(4): 914-9, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9537428

RESUMO

Although alcohol intake and hepatitis C virus (HCV) infection are the major determinants of liver cirrhosis (LC) in Western countries, the joint effect of these two factors on LC risk has not yet been adequately studied. We used data from two hospital-based case-control studies performed in Italy. Cases were 285 cirrhotic patients admitted for the first time to district hospitals for liver decompensation. Controls were 417 patients admitted during the same period, and in the same hospitals as the cases, for acute diseases unrelated to alcohol. Alcohol consumption was expressed as lifetime daily alcohol intake (LDAI). Serum HCV antibodies (anti-HCV) were detected using a second-generation test and recombinant immunoblotting assay. We found a dose-effect relationship between LDAI and the risk of LC in both anti-HCV-negative and -positive subjects. Considering the extreme LDAI categories (LDAI = 0 g, lifetime teetotalers, and LDAI = 175 g), the LC odds ratios increased from 1.0 (reference category) to 15.0 (95% CI, 7.1-31.7) and from 9.2 (95% CI, 2.0-43.2) to 147.2 (95% CI, 42.1-514.3) in anti-HCV-negative and -positive patients respectively. The interaction between LDAI and HCV showed an additive structure for LDAI < 50 g/day and a multiplicative structure for consumption > 125 g/day. Alcohol intake and HCV infection are independent risk factors for symptomatic liver cirrhosis, each being sufficient to induce the disease. In subjects with high alcohol intake, the coexistence of HCV infection multiplies the alcohol-associated risk of cirrhosis. In subjects with low alcohol intake, other factors could be involved.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Hepatite C/complicações , Cirrose Hepática/etiologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Anticorpos Anti-Hepatite C/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
12.
Scand J Gastroenterol ; 32(11): 1174-80, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9399401

RESUMO

BACKGROUND: Evidence on gender-related differences in susceptibility to alcohol-induced liver diseases is questionable with regard to both methodologic and clinical aspects. With the aim to assess the role of gender in the risk of liver cirrhosis, independently and in combination with known risk factors, data from three case-control studies performed in various Italian areas were analysed. METHODS: The cases were 462 cirrhotic patients (300 men and 162 women) admitted for the first time to hospital for liver decompensation. Controls were 651 patients (355 men and 296 women) admitted to the same hospitals during the same period as the cases, for acute diseases unrelated to alcohol. Alcohol consumption was expressed as lifetime daily alcohol intake. RESULTS: A significant and independent associations between alcohol intake, chronic hepatitis B and C virus infections, and the risk of liver cirrhosis was observed. The effect of alcohol intake was multiplicatively increased in women. The odds ratio (OR) increased from 1.0 (reference category: men, lifetime abstainers) to 31.4 (95% confidence interval (CI), 10.3-95.8) in men drinking more than 100 g/day of alcohol, and from 2.2 (95% CI, 1.0-7.1) in abstaining women to 44.8 (95% CI, 8.2-224.0) in women drinking more than 100 g/day of alcohol. An increased risk of liver cirrhosis associated with female gender independently of alcohol consumption and virus infection was also observed. CONCLUSIONS: A higher susceptibility to alcohol-induced liver diseases was confirmed for women, and an independent effect of female sex on the risk of cirrhosis was observed. Besides alcohol and viruses, some unknown gender-related factor might then be involved in the occurrence of the disease.


Assuntos
Cirrose Hepática Alcoólica/epidemiologia , Cirrose Hepática/epidemiologia , Cirrose Hepática/virologia , Adulto , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Estudos de Casos e Controles , Suscetibilidade a Doenças/induzido quimicamente , Suscetibilidade a Doenças/virologia , Feminino , Antígenos de Superfície da Hepatite B/sangue , Anticorpos Anti-Hepatite C/sangue , Humanos , Itália/epidemiologia , Cirrose Hepática Alcoólica/etiologia , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores Sexuais
13.
J Hepatol ; 27(3): 470-6, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9314123

RESUMO

BACKGROUND/AIMS: In order to evaluate the association between alcohol intake and the risk of liver cirrhosis in the absence of B and C hepatitis viruses, we analyzed data from three hospital-based case-control studies performed in various Italian areas. METHODS: From the case and control series we excluded HBsAg and/or anti-HCV positive patients. Cases were 221 cirrhotic patients admitted for the first time to hospital for liver decompensation. Controls were 614 patients admitted to the same hospitals during the same period as the cases for acute diseases unrelated to alcohol. Alcohol consumption was expressed as lifetime daily alcohol intake (LDAI). RESULTS: We found a dose-effect relationship between LDAI and the risk of liver cirrhosis (LC). Considering the extreme LDAI categories (LDAI = 0 g: lifetime teetotallers and LDAI > or = 100 g), the LC odds ratio (OR) increased from 1.0 (reference category) to 44.7 (95% confidence interval: 95% CI: 20.0-99.9). An increased risk of LC associated with the female gender independent of alcohol consumption was also observed (OR = 2.9; 95% CI: 1.8-4.6). CONCLUSIONS: Alcohol intake acts as a risk factor for symptomatic liver cirrhosis also in the absence of HBV and/or HCV infection. Besides alcohol and viruses, some unknown gender-related factors might be involved in the occurrence of the disease.


Assuntos
Consumo de Bebidas Alcoólicas , Hepacivirus/isolamento & purificação , Antígenos de Superfície da Hepatite B/sangue , Cirrose Hepática/etiologia , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Itália , Cirrose Hepática/imunologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco
14.
Gastroenterology ; 113(1): 265-76, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9207287

RESUMO

BACKGROUND & AIMS: We reported previously that patients with alcoholic liver disease (ALD) have circulating immunoglobulins reacting with cytochrome P4502E1 (CYP2E1) complexed with hydroxyethyl free radicals. The aim of this study was to investigate whether hydroxyethyl radical adducts are present on the plasma membranes of ethanol-treated hepatocytes and their role in antibody-dependent cytotoxicity. METHODS: Immunofluorescence confocal laser microscopy, Western blotting, and antibody-dependent cell-mediated cytotoxicity assay were used. RESULTS: Isolated rat hepatocytes incubated in vitro with ethanol or obtained from ethanol-treated animals showed strong surface fluorescence when exposed to rabbit anti-hydroxyethyl radical serum or sera from patients with ALD. No surface fluorescence was evident on control hepatocytes or after scavenging hydroxyethyl radicals with 4-pyridyl-1-oxide-t-butyl nitrone. The presence of CYP2E1-hydroxyethyl radical adducts on hepatocyte plasma membranes was shown by Western blot and by immunofluorescence using double staining for human and rabbit anti-CYP2E1 immunoglobulin G. Cytotoxicity was observed in ethanol-treated hepatocytes incubated with immunoglobulin G from patients with ALD and normal human blood mononuclear cells. This effect was blocked by preabsorbing the sera with human albumin complexed with hydroxyethyl radicals, which also eliminated the antibody reaction with the plasma membranes. CONCLUSIONS: Hydroxyethyl radicals bound to CYP2E1 on hepatocyte plasma membranes can target immune reactions triggered by alcohol abuse.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Citocromo P-450 CYP2E1/metabolismo , Etanol/farmacologia , Hepatopatias Alcoólicas/imunologia , Fígado/imunologia , Animais , Western Blotting , Membrana Celular/efeitos dos fármacos , Membrana Celular/imunologia , Etanol/metabolismo , Etanol/toxicidade , Radicais Livres , Humanos , Fígado/efeitos dos fármacos , Masculino , Microscopia Confocal , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/imunologia , Coelhos , Ratos , Ratos Sprague-Dawley
15.
Ital J Gastroenterol Hepatol ; 29(3): 243-8, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9646216

RESUMO

BACKGROUND: Some conditions characterized by a loss (anatomical or functional) of parietal cells of the gastric antrum, containing an alcohol-dehydrogenase, may reduce the first pass metabolism of ethanol at that level and, simultaneously, raise its bioavailability. The observation that the first pass metabolism was drastically suppressed after gastrectomy would appear to suggest that the latter condition represents a risk for the development of liver damage in patients who continue to consume alcohol even in a non relevant amount. METHODS: Consecutively enrolled in the study were 304 individuals of both sexes aged between 45 and 70 years of whom 114 gastrectomized and 190 pair-matched control subjects all submitted to an Upper Gastrointestinal Endoscopy for whatever disturbance. All the patients were diagnosed as having liver disease with routine clinical and instrumental means. Information was collected concerning the mean daily alcohol intake, both before and after the operation. RESULTS: The overall prevalence of hepatic lesions was shown to be higher in the gastrectomized than in the control group (42.1% vs 25.8%, p = 0.005). Moreover, referring only to alcohol-related hepatic lesions (steatosis, steato-fibrosis and cirrhosis), the prevalence was higher in the gastrectomized patients than in the controls (29.8% vs 17.9%, p = 0.02). As far as concerns alcohol consumption, the gastrectomized group had consumed 71 g/day and the control group 39 g/day alcohol per person (p < 0.05) in a similar period of time (35 and 33 years, respectively). Also the non alcohol-related liver damage (especially the viral type) was slightly higher in the gastrectomized patients (gastrectomized 12.3% vs control 7.9%, p = ns). Accordingly, the percentage of serum markers of viral infection was higher in this group (HBs Ag: gastrectomized 3.9% vs control 2.2%, p = ns; anti-HCV: gastrectomized 13.5% vs control 5.0%, p = 0.03). Finally, to test the eventual damaging effects of gastrectomy alone (excluding ethanol and/or viral infection), two groups of patients with a medium to low alcoholic negative assumption (30-60 g ethanol/day) and no signs of viral infection (HBsAg and anti-HCV negative) were extrapolated. In these two selected groups, the prevalence of alcoholic-related hepatic lesions were not statistically different (28 gastrectomized 20.3% vs 44 control 18.4%). CONCLUSIONS: In conclusion, data emerging from investigations on the population under study indicate that the alcohol and viral infection appear to play a more important role in determining hepatic lesions than gastroresection.


Assuntos
Etanol/metabolismo , Gastrectomia , Hepatopatias Alcoólicas/cirurgia , Hepatopatias/epidemiologia , Idoso , Doença Crônica , Feminino , Humanos , Hepatopatias Alcoólicas/metabolismo , Masculino , Pessoa de Meia-Idade
16.
Ital J Gastroenterol Hepatol ; 29(1): 38-46, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9265577

RESUMO

BACKGROUND/AIMS: Prognostic studies on cirrhosis are needed, since several attempts to obtain better survival predictors than the empirically derived Child-Pugh's score have failed. METHODS: Four hundred and ninety-four consecutive in-patients with cirrhosis at the first episode of decompensation (ascites, jaundice, encephalopathy) and/or of digestive haemorrhage from ruptured oesophageal varices were followed from admission (1983-1989) to 1993, studying the relationship between 26 prognostic variables and survival. Three prognostic models were constructed using Cox's regression model and the Receiver Operating Characteristic (ROC) analysis was used to compare their predictive ability. RESULTS: During follow-up 351 patients died (median cumulative survival 1.82 years). Child-Pugh's score (explicative variable of the first Cox's model), albumin and encephalopathy among the 5 Child-Pugh variables (second model), and oesophageal varices haemorrhage and 3 biochemical indexes among the 7 significant variables on univariate analysis (third model) correlated with survival. The area under the ROC curve of the first model did not significantly differ from that for the other 2 models. CONCLUSIONS: The Child-Pugh's score is still the best and simplest index for assessing the prognosis of liver cirrhosis.


Assuntos
Cirrose Hepática/mortalidade , Ascite/etiologia , Feminino , Hemorragia Gastrointestinal/etiologia , Encefalopatia Hepática/etiologia , Humanos , Icterícia/etiologia , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Prognóstico , Curva ROC , Taxa de Sobrevida
17.
Ital J Gastroenterol Hepatol ; 29(1): 75-80, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9265584

RESUMO

The recent availability of hepatitis C virus (HCV) infection markers has led to the hypothesis that the prevalence of alcoholic liver cirrhosis (ALC) may be far lower than has hitherto been believed. On the other hand difficulties in obtaining a reliable patient history of alcohol consumption and of making a differential diagnosis on the basis of histology suggest that the aetiology role of alcohol may be underestimated. Furthermore, epidemiological data strongly suggest that an individual susceptibility of alcoholic liver damage exists. The interaction between alcohol consumption and acquired factors, in particular hepatitis B and C viruses and nutrition, can be studied using an epidemiological approach. The concept of attributable risk, which depends on the strength of the aetiological factors and on their diffusion in the target population, is helpful in this context. Preliminary estimates suggest that alcohol is at least as important as HCV infection in causing liver cirrhosis in Italy. A nationwide study (SIDE-CIR Project) is currently being conducted in order to clarify this issue.


Assuntos
Hepatite C/complicações , Cirrose Hepática Alcoólica/complicações , Consumo de Bebidas Alcoólicas , Causalidade , Suscetibilidade a Doenças , Relação Dose-Resposta a Droga , Humanos , Cirrose Hepática Alcoólica/epidemiologia , Prevalência , Fatores de Risco
18.
Int J Epidemiol ; 26(1): 100-9, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9126509

RESUMO

BACKGROUND: Since the mid 1970s, a striking reduction in alcohol-related problems has been observed in many Western countries. Liver cirrhosis mortality is considered to be a major indicator of alcohol-related problems in the general population. The aim of the present study is to describe liver cirrhosis mortality trends in European countries between 1970 and 1989. METHODS: This is a descriptive study on liver cirrhosis mortality in 25 European countries, and in four grouped European regions. A Poisson log-linear age-period-cohort model is used to clarify whether the recent trend in mortality represents a short-term fluctuation or an emerging long-term trend. In addition, a descriptive comparison between trends in per capital alcohol consumption and liver cirrhosis mortality is conducted. RESULTS: In the whole European population and in that of Western and Southern Europe increasing period effects were observed until the second half of the 1970s followed by a decline in the next periods. In Eastern Europe the decline in period effects started in the first half of the 1980s, whereas in Northern Europe an increasing period effect was observed until the second half of the 1970s, followed by a stabilization. Similar trends were observed for per capita alcohol consumption. The age effect analysis showed a continuously rising effect in Eastern Europe, whereas an attenuation of the effect at around age 65 years was observed in Western Europe. Intermediate patterns were observed in Southern and Northern Europe. The birth cohort effect suggested that in the Western and Southern populations mortality could continue to decrease over the next decade, while in Eastern and Northern mortality is still rising and this will probably continue for the next decade. CONCLUSIONS: The age-period-cohort analysis allows targeting of health care and prevention programmes based on future trends. Aetiological and prognostic factors act differently in Europe. A better understanding of the trends would require more detailed information on alcoholism treatment rates, alcohol habits, viral hepatitic infections and other factors involved in the aetiopathogenesis of the disease.


Assuntos
Consumo de Bebidas Alcoólicas/mortalidade , Cirrose Hepática Alcoólica/mortalidade , Adulto , Distribuição por Idade , Idoso , Consumo de Bebidas Alcoólicas/epidemiologia , Estudos de Coortes , Europa (Continente)/epidemiologia , Europa Oriental/epidemiologia , Feminino , Humanos , Incidência , Modelos Lineares , Cirrose Hepática Alcoólica/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Distribuição por Sexo , Taxa de Sobrevida
19.
Gastroenterology ; 111(1): 206-16, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8698201

RESUMO

BACKGROUND & AIMS: We have previously reported that alcoholics have increased titers of immunoglobulins reacting with protein adducts of hydroxyethyl free radicals. Because hydroxyethyl radicals are produced during ethanol metabolism by liver microsomes, the aim of this study was to determine whether such antibodies recognize microsomal proteins complexed with hydroxyethyl radicals. METHODS: Liver microsomal proteins reacting with the anti-hydroxyethyl radical antibodies were characterized by an enzyme-linked immunosorbent assay and Western blotting. RESULTS: Alcoholic cirrhotics, but not patients with nonalcoholic cirrhosis or healthy subjects, had increased serum levels of immunoglobulin G and A directed against antigens produced in microsomes incubated with reduced nicotinamide adenine dinucleotide phosphate (NADPH) and ethanol. Such immunoreactivity was completely blocked when microsomes were incubated with ethanol in the presence of the spin-trapping agent 4-pyridyl-1-oxide-t-butyl nitrone or by preincubating the sera with hydroxyethyl radical-bound human albumin. Immunoblotting of proteins from human liver microsomes incubated with NADPH and ethanol showed that 86% of the sera from alcoholic cirrhotics reacted with a 52-kilodalton protein, whereas variable reactivity was observed with proteins of 78, 60, and 40 kilodaltons, respectively, The 52-kilodalton protein was identified by immunoblotting and immunoprecipitation as ethanol-inducible cytochrome P4502E1. CONCLUSIONS: Antibodies from alcoholic cirrhotics specifically recognized hydroxyethyl radical-cytochrome P4502E1 adducts, suggesting the possible implication of these antigens in the development of autoimmune reactions in alcoholic liver disease.


Assuntos
Autoanticorpos/biossíntese , Autoantígenos/imunologia , Sistema Enzimático do Citocromo P-450/imunologia , Radical Hidroxila/imunologia , Cirrose Hepática Alcoólica/imunologia , Oxirredutases N-Desmetilantes/imunologia , Adulto , Idoso , Autoantígenos/metabolismo , Western Blotting , Citocromo P-450 CYP2E1 , Sistema Enzimático do Citocromo P-450/metabolismo , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Epitopos/metabolismo , Feminino , Humanos , Radical Hidroxila/metabolismo , Imunoglobulina A/biossíntese , Imunoglobulina G/biossíntese , Cirrose Hepática Alcoólica/metabolismo , Masculino , Microssomos Hepáticos/imunologia , Microssomos Hepáticos/metabolismo , Pessoa de Meia-Idade , Oxirredutases N-Desmetilantes/metabolismo
20.
Liver ; 15(4): 202-8, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8544643

RESUMO

Our aims were to design a reproducible method of measuring life-time alcohol consumption in patients with cirrhosis, and to assess the risk of liver decompensation associated with alcohol intake using a case-control design and a multivariate analysis. We studied 439 patients ("cases") with decompensated cirrhosis, and 233 with compensated cirrhosis ("controls"). Mean life-time daily amount and duration of alcohol intake were measured by a standardized questionnaire, whose reproducibility, assessed by interviewing 75 relatives, was 70% for daily alcohol intake and 84% for duration of intake. Better reproducibility was found by re-interviewing patients at discharge from hospital. Daily alcohol intake was significantly higher in males, younger patients and patients with liver decompensation. After stratification according to the average life-time daily alcohol intake, we found a significant increase in the risk of liver decompensation from 125 g ethanol intake per day onwards. No association was found between duration of alcohol intake and risk of liver decompensation. We conclude that alcohol intake can be reliably and reproducibly measured: in patients with cirrhosis, increased alcohol intake is associated with increased risk of liver decompensation, with a significant dose-effect above a daily intake of 125 g ethanol.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Cirrose Hepática Alcoólica/etiologia , Adulto , Fatores Etários , Estudos de Casos e Controles , Feminino , Hepatite B/complicações , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Reprodutibilidade dos Testes , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários , Fatores de Tempo
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