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1.
J Viral Hepat ; 25(5): 457-464, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29152828

RESUMO

People with hepatitis C virus (HCV) infection other than genotype 1 represent a heterogeneous group. The aim of the phase 2 C-SCAPE study was to evaluate elbasvir/grazoprevir (EBR/GZR), with or without ribavirin (RBV), in participants with HCV genotype 2, 4, 5 or 6 infection. This was a part randomised, open-label, parallel-group study (NCT01932762; PN047-03) of treatment-naive, noncirrhotic participants. Participants with HCV genotype 2 infection received GZR 100 mg + RBV ± EBR 50 mg for 12 weeks and those with genotype 4, 5 or 6 infection were randomized to receive EBR/GZR ± RBV for 12 weeks. The primary endpoint was sustained virological response 12 weeks after completion of treatment (SVR12; HCV RNA <25 IU/mL). Among participants with genotype 2 infection, SVR12 was achieved by 80% (24/30) of those receiving EBR/GZR + RBV and 73% (19/26) of those receiving GZR + RBV. SVR rates were high in participants with HCV genotype 4 infection receiving EBR/GZR with and without RBV (100% [10/10] and 90% [9/10]; respectively). In contrast, the addition of RBV to EBR/GZR appeared to increase SVR12 in participants with genotype 5 infection (EBR/GZR, 25%; EBR/GZR + RBV 100% [4/4]). In participants with genotype 6 infection, SVR12 was 75% (3/4) in both those receiving EBR/GZR and those receiving EBR/GZR + RBV. The safety profile was similar across treatment arms, with adverse events tending to occur more frequently among participants receiving RBV. In conclusion, these data support the inclusion of participants with genotype 4 or 6 infection in the EBR/GZR phase 3 studies. EBR/GZR ± RBV was unsatisfactory for participants with genotype 2 or 5 infection.


Assuntos
Antivirais/administração & dosagem , Benzofuranos/administração & dosagem , Genótipo , Hepacivirus/classificação , Hepatite C Crônica/tratamento farmacológico , Imidazóis/administração & dosagem , Quinoxalinas/administração & dosagem , Ribavirina/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Amidas , Antivirais/efeitos adversos , Benzofuranos/efeitos adversos , Carbamatos , Ciclopropanos , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Feminino , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Imidazóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Quinoxalinas/efeitos adversos , Ribavirina/efeitos adversos , Sulfonamidas , Resposta Viral Sustentada , Resultado do Tratamento , Adulto Jovem
2.
J Viral Hepat ; 24(10): 895-899, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28470815

RESUMO

Elbasvir (EBR; HCV NS5A inhibitor) and grazoprevir (GZR; HCV NS3/4A protease inhibitor) are approved as a fixed-dose combination to treat patients chronically infected with HCV genotypes 1 and 4. During the development programme and supported by in vitro potency, the efficacy of EBR+GZR was assessed in HCV GT3-infected patients. This study's aim was to determine the efficacy and tolerability of 12 or 18 weeks of EBR+GZR with ribavirin (RBV) in treatment-naïve, noncirrhotic HCV GT3-infected patients. Randomized patients received open-label EBR (50 mg once daily) + GZR (100 mg once daily) + RBV. The primary efficacy objective was to evaluate the sustained virologic response rates 12 weeks after the end of all study therapy (SVR12). SVR12 rates (95% confidence interval) were 45.0% (23.1, 68.5) and 57.1% (34.0, 78.2) after treatment with EBR+GZR+RBV for 12 weeks or 18 weeks, respectively. On-treatment virologic failure was observed in 41% (17 of 41) of patients. At virologic failure, resistance-associated substitutions (RASs) with a >five-fold shift in potency occurred in the NS3 region in six (35%) patients and in the NS5A region in 16 (94%) patients. The most common RAS at virologic failure was Y93H in NS5A which was identified in 13 of 17 (76%) patients. The efficacy of EBR+GZR+RBV was suboptimal in HCV GT3-infected patients due to a high rate of on-treatment virologic failure and treatment-emergent RASs which demonstrates an inadequate barrier to the development of GT3 resistance. However, rapid viral clearance demonstrated the antiviral activity of EBR+GZR+RBV in GT3-infected patients.clinicaltrials.gov: NCT01717326.


Assuntos
Antivirais/uso terapêutico , Benzofuranos/uso terapêutico , Genótipo , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Imidazóis/uso terapêutico , Quinoxalinas/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Idoso , Amidas , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Benzofuranos/administração & dosagem , Benzofuranos/efeitos adversos , Carbamatos , Ciclopropanos , Farmacorresistência Viral , Quimioterapia Combinada , Feminino , Hepacivirus/efeitos dos fármacos , Humanos , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Quinoxalinas/administração & dosagem , Quinoxalinas/efeitos adversos , RNA Viral , Ribavirina/administração & dosagem , Ribavirina/efeitos adversos , Sulfonamidas , Fatores de Tempo , Falha de Tratamento , Resultado do Tratamento , Carga Viral
3.
J Viral Hepat ; 19(4): 263-70, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22404724

RESUMO

Long-term studies in adults indicate that sustained virologic response (SVR) after combination treatment for chronic hepatitis C (CHC) predicts long-term clearance. Although peginterferon plus ribavirin is now standard care for children with CHC, long-term follow-up studies are not yet available. This study evaluated durability of virologic response over 5 years in children previously treated with interferon alfa-2b plus ribavirin (IFN/R). Ninety-seven of 147 children with CHC, who were treated with IFN/R and completed the 6-month follow-up in two previous clinical trials, participated in this long-term follow-up study. All were assessed annually for up to 5 years; patients with SVR were assessed for durability of virologic response. Children with SVR (n = 56) and those with detectable hepatitis C virus (HCV) RNA 24-week post-treatment (n = 41) were followed for a median of 284 weeks. Overall, 70% (68/97) of patients completed the 5-year follow-up. One patient with genotype 1a CHC had SVR and relapsed at year 1 of follow-up with the same genotype. Kaplan-Meier estimate for sustained response at 5 years was 98% (95% CI: 95%, 100%). Six patients with low-positive HCV RNA levels (n = 4) or missing HCV RNA at the 24-week follow-up visit (n = 2) in the initial treatment studies had virologic response during this long-term follow-up study. Linear growth rate was impaired during treatment with rapid increases in the immediate 6 months post-treatment. Mean height percentile at the end of the 5-year follow-up was slightly less than the mean pretreatment height percentile. Five patients experienced serious adverse events; none related to study drug exposure. SVR after IFN/R predicts long-term clearance of HCV in paediatric patients; growth normalized in the majority of children during the long-term follow-up. Similar long-term results could be expected after peginterferon alfa-2b plus ribavirin treatment.


Assuntos
Antivirais/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Ribavirina/administração & dosagem , Adolescente , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Feminino , Seguimentos , Humanos , Interferon alfa-2 , Masculino , Proteínas Recombinantes/administração & dosagem , Resultado do Tratamento , Adulto Jovem
4.
Food Chem Toxicol ; 46(4): 1389-97, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17950517

RESUMO

An extract of the Mediterranean carob (Ceratonia siliqua L.) pod (carob fibre extract), products formed after its fermentation by the gut flora and the major phenolic ingredient gallic acid (GA), were comparatively investigated for their influence on survival and growth parameters of colon adenocarcinoma HT29 cells and adenoma LT97 cells. Hydrogen peroxide (H2O2) formation in the cell culture media was quantified. After 1h 97+/-4 microM or 70+/-15 microM were found in HT29 medium and 6+/-1 microM or 3+/-3 microM in LT97 medium for carob fibre extract or GA, respectively. After 72 h carob fibre extract reduced survival of rapidly proliferating HT29 cells (by 76.4+/-12.9%) whereas metabolic activity and DNA-synthesis were only transiently impaired. Survival of slower growing LT97 cells was less decreased (by 21.5+/-12.9%), but there were marked effects on DNA-synthesis (reduction by 95.6+/-7%, 72 h). GA and fermented carob fibre did not have comparable effects. Thus, carob fibre extract resulted in H2O2 formation, which, however, could not explain impairment of cell growth. The differently modulated growth of human colon cell lines was more related to proliferation rates and impairment of DNA-synthesis than to H2O2 formation.


Assuntos
Adenocarcinoma/patologia , Adenoma/patologia , Antineoplásicos Fitogênicos , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Fibras na Dieta/farmacologia , Fabaceae/química , Adenocarcinoma/tratamento farmacológico , Adenoma/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Neoplasias do Colo/tratamento farmacológico , Meios de Cultura , DNA de Neoplasias/biossíntese , Fermentação , Células HT29 , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Fenóis , Espectrometria de Massas por Ionização por Electrospray , Sulfóxidos , Xilenos/química
5.
Food Chem Toxicol ; 41(12): 1727-38, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14563398

RESUMO

Although it is already known that carob fibre contains several classes of polyphenolic substances, a comprehensive analysis of these has not been conducted to date. Therefore, the major polyphenolic compounds were extracted with organic solvents, and, following fractionation by normal-phase column chromatography on silicic acid, their structures were elucidated by liquid-chromatography electrospray-ionisation mass spectrometry (LC-ESI), nano-electrospray-ionisation mass spectrometry (ESI-MS), and gas-chromatography mass spectrometry (GC-MS). In addition, complete 1H and 13C NMR assignments were obtained for the isolated gallotannins 1,6-di-, 1,2,6-tri- and 1,2,3,6-tetra-O-galloyl-beta-D-glucose. Carob fibre was found to contain a rich variety of phenolic antioxidants. A total of 24 polyphenol compounds were identified with a yield of 3.94 g/kg (dry weight). The profile was dominated by gallic acid in various forms: free gallic acid (42% of polyphenols by weight), gallotannins (29%), and methyl gallate (1%), while simple phenols, mainly cinnamic acid, made up about 2% of the total. Flavonoids represented 26% of the polyphenols, and the major components were identified as the glycosides myricetin- and quercetin-3-O-alpha-L-rhamnoside (ca. 9% and 10%, respectively). These data indicate that carob fibre is rich in both amount and variety of phenolic antioxidant substances, and its inclusion in the diet may have chemopreventive properties.


Assuntos
Fibras na Dieta/análise , Flavonoides/química , Fenóis/química , Polissacarídeos/química , Cromatografia por Troca Iônica , Flavonoides/isolamento & purificação , Galactanos , Cromatografia Gasosa-Espectrometria de Massas , Hidrólise , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Mananas , Fenóis/análise , Fenóis/isolamento & purificação , Gomas Vegetais , Polifenóis , Ácido Silícico/química , Espectrometria de Massas por Ionização por Electrospray
6.
Eur J Nutr ; 42(5): 235-42, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14569404

RESUMO

BACKGROUND: Recently, insoluble fibre from carob pulp has been found to affect blood lipids in animals in a similar manner as soluble dietary fibre. AIM OF THE STUDY: To investigate whether a carob pulp preparation containing high amounts of insoluble fibre has a beneficial effect on serum cholesterol in humans. METHODS: Volunteers (n = 58) with hypercholesterolemia were recruited to participate in a randomised, double- blind, placebo-controlled and parallel arm clinical study with a 6 week intervention phase. All participants consumed daily both, bread (two servings) and a fruitbar (one serving) either with (n = 29) or without (n = 29) a total amount of 15 g/d of a carob pulp preparation (carob fibre). Serum concentrations of total, LDL and HDL cholesterol and triglycerides were assessed at baseline and after week 4 and 6. RESULTS: The consumption of carob fibre reduced LDL cholesterol by 10.5 +/- 2.2% (p = 0.010). The LDL:HDL cholesterol ratio was marginally decreased by 7.9 +/- 2.2 % in the carob fibre group compared to the placebo group (p = 0.058). Carob fibre consumption also lowered triglycerides in females by 11.3 +/- 4.5% (p = 0.030). Lipid lowering effects were more pronounced in females than in males. CONCLUSION: Daily consumption of food products enriched with carob fibre shows beneficial effects on human blood lipid profile and may be effective in prevention and treatment of hypercholesterolemia.


Assuntos
LDL-Colesterol/sangue , Colesterol/sangue , Fibras na Dieta/administração & dosagem , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/prevenção & controle , Polissacarídeos/uso terapêutico , Adulto , Idoso , Análise de Variância , Anticolesterolemiantes/farmacologia , Anticolesterolemiantes/uso terapêutico , Apolipoproteínas/sangue , Método Duplo-Cego , Feminino , Alimentos Fortificados , Galactanos , Humanos , Hipercolesterolemia/sangue , Masculino , Mananas , Pessoa de Meia-Idade , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Gomas Vegetais , Polissacarídeos/farmacologia , Distribuição por Sexo , Fatores de Tempo , Resultado do Tratamento , Triglicerídeos/sangue
7.
Adv Ther ; 18(5): 230-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11783460

RESUMO

The lipid-lowering effect of a carob pulp preparation rich in insoluble dietary fiber and polyphenols was investigated in a noncomparative, open-label pilot study. Over 8 weeks, 47 volunteers with moderate hypercholesterolemia (total cholesterol 232-302 mg/dL) consumed 15 g of carob per day in three products (breakfast cereal, fruit muesli bar, powdered drink) as a supplement to their regular diet. After 4 weeks, reductions of 7.1% in mean total cholesterol and 10.6% in LDL cholesterol were noted; respective decreases after 6 weeks were 7.8% and 12.2% (all P<.001). HDL cholesterol and triglyceride levels remained unchanged. Overall compliance was good. Only 3 volunteers (6%) reported a sensation of fullness, which led to 2 of the 3 dropouts. The carob preparation may have value in the dietary treatment of hypercholesterolemia.


Assuntos
Anticolesterolemiantes/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Lipídeos/sangue , Extratos Vegetais/uso terapêutico , Polissacarídeos/uso terapêutico , Adulto , Idoso , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Galactanos , Humanos , Hipercolesterolemia/sangue , Masculino , Mananas , Pessoa de Meia-Idade , Projetos Piloto , Gomas Vegetais , Fatores de Tempo , Resultado do Tratamento , Triglicerídeos/sangue
8.
Hepatology ; 30(5): 1269-75, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10534349

RESUMO

Mutations in Jagged1, a Notch ligand, have been shown to result in Alagille syndrome (AGS), however, the causal link between haploinsufficiency of Jagged1 and intrahepatic ductal paucity is unknown. This survey was performed to determine the expression pattern of Jagged1 in the fetal and postnatal liver. Reverse transcription polymerase chain reaction (RT-PCR) showed Jagged1 expression in all samples studied including rat liver embryonic days 16 to 21, 1-day-old, 1-week-old, and 2-month-old adult rats. RT-PCR detected Jagged1 in total liver RNA extracted from cadaver organ donor samples from reduced human grafts and explanted native livers from a variety of pediatric disorders including AGS, biliary atresia, congenital hepatic fibrosis, sclerosing cholangitis, cystic fibrosis, fulminant hepatic failure, tyrosinemia, and chronic rejection. Immunohistochemistry showed Jagged1 expression in human fetal samples localized to the ductal plate from 14-week gestation onward. Expression in the postnatal liver was seen in biliary epithelium and zone 3 hepatocytes. In conclusion, these studies show that Jagged1 is expressed in the fetal and postnatal liver in health and disease. We show localization of expression by immunohistochemistry to ductal plate epithelium in human fetal samples and to the biliary epithelium and zone 3 hepatocytes in human postnatal samples. Our results show the localization of Jagged1 in fetal liver and demonstration of Jagged1 expression in postnatal rat and human liver specimens. Further studies of Jagged1 and the Notch signaling pathway are expected to elucidate mechanisms of the regulation of biliary epithelial growth and development.


Assuntos
Envelhecimento/metabolismo , Desenvolvimento Embrionário e Fetal/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Fígado/metabolismo , Proteínas/genética , Animais , Proteínas de Ligação ao Cálcio , Criança , Feto , Idade Gestacional , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Proteína Jagged-1 , Fígado/embriologia , Fígado/crescimento & desenvolvimento , Hepatopatias/genética , Hepatopatias/metabolismo , Proteínas de Membrana , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Serrate-Jagged
10.
Am J Physiol ; 273(5): R1709-18, 1997 11.
Artigo em Inglês | MEDLINE | ID: mdl-9374814

RESUMO

Sepsis in rats decreases the hepatic expression of the gluconeogenic enzyme glucose-6-phosphatase (G6Pase). The aim of this study was to investigate the relationship among G6Pase transcription, mRNA, enzymatic activity, and serum glucose levels at different intervals during mild or fulminant sepsis. Both fulminant and mild sepsis immediately decreased hepatic G6Pase mRNA levels. In mild sepsis, levels began to recover late in the time course. Serum glucose levels were maintained in mild sepsis but decreased markedly in fulminant sepsis. G6Pase transcription after fulminant sepsis decreased and never recovered. A similar transcriptional decrease was noted in mild sepsis, but some recovery occurred in this state. Histochemistry after mild sepsis revealed a decrease in G6Pase protein and enzymatic activity that paralleled transcription. These studies suggest that changes in G6Pase transcription and activity are early markers for sepsis-induced alterations in hepatic function. Mechanisms other than gene expression and enzymatic activity serve to maintain glucose levels in mild sepsis, but in the fulminant disorder, compensatory mechanisms fail and hypoglycemia develops.


Assuntos
Regulação Enzimológica da Expressão Gênica , Glucose-6-Fosfatase/biossíntese , Fígado/enzimologia , Sepse/enzimologia , Transcrição Gênica , Animais , Glicemia/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Fígado/patologia , Masculino , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Valores de Referência , Sepse/sangue , Sepse/patologia
11.
Am J Clin Nutr ; 66(4 Suppl): 1053S-1057S, 1997 10.
Artigo em Inglês | MEDLINE | ID: mdl-9322586

RESUMO

Although the virtues of the Mediterranean diet have been advocated since the Renaissance, adoption of the diet outside the Mediterranean region has proved difficult but not impossible. Efforts at promoting dietary change have been explored in the writings of Europeans and Americans since 1614 when Giacomo Castelvetro, an exile from Modena, Italy, published a book in England on Italian fruit, herbs, and vegetables. The historical causes of resistance by groups and individuals-culture, class, sex, and human psychology-are revealed by asking the question, What does food mean to people? Particularly instructive are failed efforts by well-meaning late-19th-century American reformers to hasten the assimilation of newly arrived immigrants by interfering with their eating habits. The establishment of the New England Kitchen, which provided inexpensive Yankee cooking intended to Americanize poor immigrants, served only to expedite food distribution networks between California farms and urban centers, allowing mainly Mediterranean groups to eat their customary foods. Successful efforts at change are also explored, leading to the conclusion that the satisfying flavors of the Mediterranean diet provide the best chance of influencing people to abandon unhealthy foods in favor of fresh vegetables, fruit, grains, and olive oil. The diet must be promoted, however, not only by medical and nutritional authorities, but also by people who have the power to persuade: authorities on cooking and experts in advertising and marketing.


Assuntos
Dieta/história , Inglaterra , Comportamento Alimentar , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , Humanos , Região do Mediterrâneo , Política Nutricional/história , Estados Unidos
13.
Mol Cell Biol ; 17(7): 4096-104, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9199345

RESUMO

Serine-arginine (SR)-rich proteins are believed to be important in mediating alternative pre-mRNA splicing. HRS/SRp40 expression is elevated in liver cell proliferation during development, regeneration, and oncogenesis. We tested whether HRS expression correlates with the appearance of alternatively spliced fibronectin transcripts during liver growth. HRS was highly expressed during the proliferative phase of liver development, correlating with expression of the fibronectin EIIIB alternative exon. In regenerating liver, HRS protein was induced in a time course consistent with the observed increase in fibronectin transcripts containing the EIIIB exon, particularly in nonparenchymal liver cells. Furthermore, in an in vivo assay, HRS, and not other SR proteins, directly mediated EIIIB exon inclusion in the fibronectin transcript. This alternative splicing was dependent on a purine-rich region within the EIIIB exon to which HRS specifically bound. We have established that HRS has the potential to contribute to the regulation of fibronectin pre-mRNA splicing during liver growth. Changes in fibronectin forms may be important in modifying liver architecture during the proliferative response, thus providing a potential mechanism by which SR proteins may participate in cellular growth control.


Assuntos
Processamento Alternativo , Fibronectinas/genética , Regeneração Hepática/fisiologia , Fígado/fisiologia , Proteínas Nucleares/genética , Fosfoproteínas/genética , RNA Mensageiro/genética , Animais , Células Cultivadas , Éxons , Feminino , Regulação da Expressão Gênica , Hepatectomia , Precursores de Ácido Nucleico/metabolismo , Proteínas de Ligação a RNA , Ratos , Fatores de Processamento de Serina-Arginina
14.
Am J Physiol ; 271(3 Pt 2): R593-600, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8853380

RESUMO

Hepatocellular dysfunction in sepsis may be neutrophil mediated. We therefore tested the hypothesis that sepsis-induced neutrophil accumulation is associated with increased expression of the chemokine, cytokine-induced neutrophil chemoattractant (CINC). In Sprague-Dawley rats made septic by cecal ligation and puncture, we demonstrate a time-dependent increase in CINC mRNA, which returns to baseline by 48 h. By in situ hybridization, this mRNA is present in hepatocytes and nonparenchymal cells. CINC protein levels in septic animals parallel mRNA levels and resolve by 48 h. Because CINC expression is induced by cytokines including tumor necrosis factor-alpha (TNF- alpha), we show, by immunohistochemistry, that sepsis elevates intrahepatic TNF-alpha. Finally, because the CINC promoter is transactivated by the transcription factor, nuclear factor kappa B (NF-kappa B), we determined that hepatic NF-kappa B DNA binding increases dramatically, peaking 16 h after cecal ligation and puncture. Thus activated NF-kappa B may mediate CINC induction in sepsis. This constellation of findings suggests a mechanism by which sepsis may induce neutrophil accumulation in the liver and may have implications regarding sepsis-induced hepatic dysfunction.


Assuntos
Quimiocinas CXC , Fatores Quimiotáticos/metabolismo , Substâncias de Crescimento/metabolismo , Infecções/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Fígado/metabolismo , Animais , Fatores Quimiotáticos/genética , DNA/fisiologia , Substâncias de Crescimento/genética , Masculino , NF-kappa B/fisiologia , Veia Porta , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , Fator de Necrose Tumoral alfa/metabolismo
15.
Am J Physiol ; 271(1 Pt 1): G121-9, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8760115

RESUMO

Mechanisms controlling the tyrosine phosphorylation of cellular proteins are important in the regulation of cellular processes including growth and differentiation. It has become clear that a number of protein tyrosine phosphatases (PTPases) that dephosphorylate tyrosyl residues may play a role in the growth response, both in growth-promoting and growth-inhibiting capacities. We identified PRL-1, a unique nuclear PTPase that is an immediate-early gene in liver regeneration and is positively associated with growth, including fetal and neoplastic hepatic growth and anchorage-independent growth after overexpression in fibroblasts. In this study, we show that PRL-1 nuclear protein levels in regenerating liver parallel those of its mRNA, although the peak occurs later, just before the onset of DNA synthesis. We further show that PRL-1 is significantly expressed in intestinal epithelia and that, in contrast to the expression pattern of PRL-1 in liver, its expression is associated with cellular differentiation in intestine. Specifically, PRL-1 is expressed in villus but not crypt enterocytes and in confluent differentiated but not undifferentiated proliferating Caco-2 colon carcinoma cells. The expression of PRL-1 in intestine shows inverse correlation with proliferating cell nuclear antigen expression, a marker for S-phase cells. These results suggest that PRL-1 may play different roles in these two digestive tissues. Such a dichotomy of roles has previously been described for some protein tyrosine kinases and might be due to the availability of alternate substrates in different tissues.


Assuntos
Proteínas Imediatamente Precoces/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/citologia , Fígado/citologia , Fígado/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Células 3T3 , Adulto , Animais , Células CACO-2/metabolismo , Proteínas de Ciclo Celular , Diferenciação Celular , Divisão Celular , Núcleo Celular/enzimologia , Feto/metabolismo , Hepatectomia/métodos , Humanos , Proteínas Imediatamente Precoces/genética , Intestinos/embriologia , Regeneração Hepática , Proteínas de Membrana , Camundongos , Microvilosidades/metabolismo , Proteínas de Neoplasias , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Tirosina Fosfatases/genética , RNA Mensageiro/metabolismo
16.
Hepatology ; 24(1): 65-71, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8707285

RESUMO

Patients with hereditary tyrosinemia type 1 have a deficiency of fumarylacetoacetate hydrolase (FAH) and develop progressive hepatocellular dysfunction with a high risk of malignant transformation. Serum alpha-fetoprotein levels are frequently elevated in these patients; therefore, this commonly used marker of tumorigenesis is inadequate. To date, no literature exists describing the hepatic gene alterations in patients with this disease. We analyzed the expression of a panel of proliferation associated and liver-specific genes in the liver of a 33 month-old girl at the time of orthotopic liver transplantation. This study provides information that may be useful in developing markers for malignancy and understanding the pathogenesis of this disease. Gene expression patterns of two regenerating nodules and total liver from the patient with FAH deficiency were compared with control donor liver. Liver-specific and growth-induced genes with altered expression in the tyrosinemic liver included several functional classes: structural proteins (actin, thrombospondin), transcription factors (c-fos, egr-1, C/EBPalpha), liver-specific enzymes (glucose-6-phosphatase [G6Phase], and secreted factors (insulin-like growth factor binding protein 1 [GFBP-1]. Isolated macronodules demonstrated varied patterns of expression, suggesting that they do not form a homogeneous cellular environment. In the tyrosinemic liver, IGFBP-1 messenger RNA expression was high and G6Phase messenger RNA was not detectable. Although G6Phase and IGFBP-1 are coexpressed in regenerating liver, immunohistochemistry in the tyrosinemic liver demonstrated a mutually exclusive distribution for the two proteins in a tissue section with features of dysplasia. We propose that cells in these areas may have an aberrant transcription factor and growth factor "milieu" that leads to altered gene and protein expression. These molecular alterations are reflected in dysplastic histologic changes and may ultimately predispose to the development of malignancy.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Expressão Gênica , Neoplasias Hepáticas/genética , Fígado/metabolismo , Fígado/patologia , Biossíntese de Proteínas , Erros Inatos do Metabolismo dos Aminoácidos/metabolismo , Erros Inatos do Metabolismo dos Aminoácidos/patologia , Biomarcadores , Biomarcadores Tumorais , Ciclo Celular , Pré-Escolar , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Hidrolases/deficiência , Hidrolases/genética , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/patologia , Transplante de Fígado , Imageamento por Ressonância Magnética , Proteínas/genética , Fatores de Risco , alfa-Fetoproteínas/análise
17.
Adolesc Med ; 6(3): 387-396, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10358324

RESUMO

Because of advances in diagnosis and treatment, cystic fibrosis patients are living longer. With increased survival, intestinal, pancreatic, and hepatobiliary involvement causes significant disease. In this article, the authors focus on the gastrointestinal, nutritional, and hepatobiliary manifestations of cystic fibrosis that may be encountered in the older child and adolescent.

18.
Hepatology ; 22(3): 906-14, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7657299

RESUMO

The liver shows maximal cellular growth during fetal development and after partial hepatectomy. Exploring overlaps in gene expression patterns in these two types of hepatic growth may provide insight into common regulatory pathways. The expression of a large number of growth-induced and liver-specific genes induced in liver regeneration has been examined in the perinatal liver from several days prenatal to 4 weeks postnatal when the major growth phase of the liver ceases. As in liver regeneration, many growth-induced genes, such as PRL-1 and beta-actin, are expressed at a high level throughout the temporal course of liver development and correlate with the proliferative state. The level of fetal liver expression of these genes is similar to peak expression found in the regenerating liver, suggesting that common pathways of transcriptional regulation exist in the two types of proliferation. A subset of liver-restricted immediate-early genes including, IGFBP-1, CL-6, and glucose-6-phosphatase (G6Pase) are induced in regenerating liver and may be important in maintaining hepatic metabolism during regeneration. In developing liver, these genes are expressed primarily in the perinatal period but, unlike the regenerating liver, are not coinduced. For instance, at birth, G6Pase is induced, whereas CL-6 is downregulated. In situ analyses confirm that a proliferation associated gene PRL-1 is expressed in multiple cell types throughout the developing liver, whereas the expression of liver-specific genes is confined to hepatocytes. Taken together, these findings imply that significant similarities and differences in transcriptional regulation and hormonal milieu exist in liver during regeneration and development.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Animais Recém-Nascidos/fisiologia , Feto/fisiologia , Expressão Gênica , Regeneração Hepática/fisiologia , Fígado/embriologia , Fígado/fisiologia , Animais , Divisão Celular , Feminino , Genes Precoces , Trabalho de Parto , Fígado/citologia , Gravidez , Ratos , Ratos Endogâmicos F344
19.
J Clin Invest ; 96(3): 1351-65, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7657810

RESUMO

During the period of rapid cell growth which follows a two-thirds partial hepatectomy, the liver is able to compensate for the acute loss of two-thirds of its mass to maintain serum glucose levels and many of its differentiation-specific functions. However certain hepatic transcription factors, C/EBP alpha and beta, which are important for establishment and maintenance of the differentiated state, have been shown to be antagonistic to cellular proliferation. To study the interplay between differentiation and cell growth in the liver regeneration model of hepatocyte proliferation, we characterized the expression of C/EBP alpha and beta transcription factors throughout the temporal course of liver regeneration. As determined by immunoblot, the level of C/EBP alpha decreases more than twofold during the mid to late G1 and S phase (8-24 h after hepatectomy) coordinately with a threefold increase in expression of C/EBP beta. Renormalization of the levels of these proteins occurs after the major proliferative phase. This inverse regulation of C/EBP alpha and beta results in up to a sevenfold increase in the beta / alpha DNA binding ratio between 3 and 24 h after hepatectomy that may have an important impact on target gene regulation. However, total C/EBP binding activity in nuclear extracts remains relatively constant during the 7-d period after hepatectomy. By immunohistochemistry, both C/EBP alpha and beta are expressed in virtually all hepatocyte nuclei throughout the liver during the temporal course of liver regeneration, and there is no exclusion of expression from hepatocytes that are expressing immediate-early gene products or undergoing DNA synthesis. The persistent expression of C/EBP alpha and beta isoforms predicts that C/EBP proteins contribute to the function of hepatocytes during physiologic growth and that significant amounts of these proteins do not inhibit progression of hepatocytes into S phase of the cell cycle.


Assuntos
Ciclo Celular , Proteínas de Ligação a DNA/biossíntese , DNA/biossíntese , Regeneração Hepática , Fígado/metabolismo , Proteínas Nucleares/biossíntese , Fatores de Transcrição/biossíntese , Animais , Sequência de Bases , Proteínas Estimuladoras de Ligação a CCAAT , Diferenciação Celular , Divisão Celular , Sequência Consenso , Feminino , Fase G1 , Regulação da Expressão Gênica , Genes Precoces , Hepatectomia , Cinética , Fígado/citologia , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Regiões Promotoras Genéticas , Ratos , Ratos Endogâmicos F344 , Valores de Referência , Fase S , Fatores de Tempo , Fatores de Transcrição/metabolismo , Ativação Transcricional , Transfecção
20.
J Clin Invest ; 95(2): 832-41, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7860767

RESUMO

The regenerating liver after partial hepatectomy is one of the few physiologic models of cellular proliferation in the adult animal. During hepatic regeneration, the animal is able to maintain metabolic homeostasis despite the acute loss of two thirds of hepatic tissue. In examining the molecular mechanisms regulating hepatic regeneration, we isolated novel immediate-early genes that are rapidly induced as the remnant liver undergoes the transition from its normal quiescent state into the G1 phase of the cell cycle. One of the most rapidly and highly induced genes which we initially termed RL-1, encodes rat glucose-6-phosphatase (rG6Pase). G6Pase mRNA peaks at 30 min and 36-48 h after hepatectomy correlating with the first and second rounds of cell division. This finding is compatible with studies that showed that G6Pase enzyme activity increases during liver regeneration. However, the increase in G6Pase mRNA is much more dramatic, indicating that it is a more sensitive indicator of this regulation. G6Pase gene expression peaks in the perinatal time period in the liver and remains elevated during the first month of life. The expression of the G6Pase gene is also dramatically elevated in BB diabetic rats, again higher than the enzyme elevation, and its relative induction after partial hepatectomy is blunted in these animals. Insulin treatment of partially hepatectomized diabetic animals downregulates the expression of G6Pase mRNA. Using specific antibodies against G6Pase, we detect a 36-kD G6Pase protein, and its level is elevated in regenerating and diabetic livers. The pattern of G6Pase mRNA expression appears to reflect similar changes in insulin and glucagon levels which accompany diabetes and hepatic proliferation. The elevation of G6Pase expression in these conditions is indicative of its importance as a regulator of glucose homeostasis in normal and abnormal physiologic states.


Assuntos
Diabetes Mellitus Tipo 1/enzimologia , Expressão Gênica , Glucose-6-Fosfatase/biossíntese , Glucose-6-Fosfatase/genética , Regeneração Hepática , Fígado/enzimologia , Células 3T3 , Animais , Sequência de Bases , Glicemia/metabolismo , Northern Blotting , Ciclo Celular , Linhagem Celular , Primers do DNA , DNA Complementar , Fase G1 , Hepatectomia , Immunoblotting , Insulina/sangue , Fígado/citologia , Fígado/fisiologia , Neoplasias Hepáticas Experimentais , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Ratos , Ratos Endogâmicos BB , Células Tumorais Cultivadas
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