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1.
Infection ; 40(2): 173-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22095532

RESUMO

BACKGROUND: Pegylated interferon (PEG-IFN) and ribavirin is the most effective treatment for chronic hepatitis C virus (HCV) hepatitis, but the rate of sustained virological response (SVR) remains approximately 50%, and 15-20% of all treated patients have a virological relapse after completing the treatment. Studies on the SVR have failed to discriminate between non-responders and relapsers. AIMS: To identify the risk factors for relapse among patients with an end-of-treatment response (ETR). METHODS: We retrospectively analyzed 281 patients consecutively treated with PEG-IFN and ribavirin with a follow-up period of at least 24 weeks. The baseline details collected on each patient included demographic data, histological features, and biochemical profiles. RESULTS: Forty-six patients (16.4%) relapsed during the first 6 months of follow-up after discontinuing the therapy. Relapser patients were significantly older, had more steatosis, fibrosis, and showed significantly lower rapid virological response (RVR) rates compared with SVR patients. By logistic regression analysis, only the absence of RVR was found to be significantly associated with relapses in both subgroups of patients with genotypes 1 and 4 (p < 0.004) and those with genotypes 2 and 3 (p < 0.006). Severe fibrosis was also predictive of relapsing disease, but only for genotypes 2 and 3 patients (p < 0.003). During the treatment, serum HCV-RNA decreased more rapidly in patients with SVR compared to non-responder and relapser patients (p < 0.001). Interestingly, relapser patients exhibited an intermediate serum HCV-RNA decay during the first 4 weeks of therapy. CONCLUSION: Among HCV patients treated with PEG-IFN and ribavirin, the absence of RVR was the most important independent predictor of relapse, independent of the HCV genotype. In the subgroup of genotypes 2 and 3 patients, the severity of fibrosis was also an important factor associated with the relapse rate.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Análise de Variância , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/fisiologia , Hepatite C Crônica/genética , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , RNA Viral/genética , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Fatores de Risco , Prevenção Secundária , Fatores de Tempo , Carga Viral
2.
Transplant Proc ; 40(6): 1974-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18675104

RESUMO

BACKGROUND AND AIM: Hepatitis C virus (HCV)-related cirrhosis is one of the leading indication for liver transplantation (LT) and a major risk factor for the development of hepatocellular carcinoma (HCC). HCV recurrence after LT is universal. This study evaluated HCV recurrence and survival in patients transplanted for HCV and HCC. METHODS: We evaluated all adults transplanted for HCV cirrhosis between January 1999 and December 2006, HCC was diagnosed on the explant and HCV recurrence confirmed on protocol liver biopsies performed at 6 months and yearly after LT. The sustained viral response (SVR) was defined as HCV-RNA undetectable at 6 months after therapy discontinuation. The patient survival rates were assessed with Kaplan-Meier curves and the chi-square test was used when appropriate. RESULTS: Two hundred sixteen patients underwent LT for HCV including 153 men and 63 women of mean age 54 years with a mean follow-up of 35 months. There were 71 (33%) HCC(+) patients. At 1, 3, and 5 years from LT severe fibrosis (Scheuer 3-4) due to the HCV recurrence was reported in 18%, 14%, and 11% for HCC(+) and 14%, 16%, and 28% for HCC(-) patients respectively (P=NS). HCC recurred only in 3 (4%) patients at a mean follow-up of 3 years. Patients who received antiviral treatment after LT were 10% HCC(+) and 12% HCC(-) patients (P=NS). SVR was seen in 3/7 (43%) of HCC(+) and in 10/18 (55%) of HCC(-) patients (P=NS). At 1, 3, and 5 years the patient survivals was 91%, 86%, and 86% for HCC(+) and 94%, 86%, and 83% for HCC(-) patients, respectively (P=NS). CONCLUSIONS: Severe fibrosis due to HCV recurrence, which increases over time, involves one third of transplanted patients at 5 years after LT. The long-term survival was identical among HCC(+) compared to HCC(-) recipients. The recurrence of HCC was negligible and did not affect patient survival.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatite C/patologia , Hepatite C/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/fisiologia , Adulto , Idoso , Carcinoma Hepatocelular/complicações , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/complicações , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Taxa de Sobrevida
3.
Transplant Proc ; 38(4): 1127-30, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16757285

RESUMO

BACKGROUND: Hepatitis C virus (HCV) reinfection after liver transplantation is a virtually constant finding and leads to chronic hepatitis and cirrhosis in variable proportions. This study aimed to assess the safety and efficacy of alpha-interferon (IFN) plus ribavirin for recurrent HCV following liver transplantation. PATIENTS AND METHODS: Thirty of 55 patients (54.5%) with histologically proven HCV recurrence after liver transplantation were given antiviral therapy (alpha-IFN at a dose of 6 MU x 3 x week IM associated with oral ribavirin 1 g/d for 12 months) and followed up for a further 12 months after the end of the treatment. Liver and renal function tests, hemocytometric values, and HCV-RNA were assessed every 3 months throughout the therapy and follow-up. Liver biopsy was performed before and after the treatment and after another 12 months of follow-up. RESULTS: Eight patients (26.7%) were withdrawn from the treatment due to adverse events and another 8 (26.7%) needed a dosage reduction. Eleven patients (36.7%) had a biochemical and virological response, becoming aminotransferase and HCV-RNA negative at the end of the treatment; 6 patients (20%) still had a sustained response after 12 months of follow-up. All 6 patients are clinically stable at 6 years after completing the antiviral therapy. A low viral load before therapy was a positive predictor of sustained response. No histologically significant improvement was seen at the end of the therapy or after the follow-up. CONCLUSIONS: The combination of alpha-IFN plus ribavirin induced a sustained virologic response in 20% of liver transplant recipients with recurrent HCV, but intolerance of the therapy prompted its discontinuation or a dosage reduction in a large proportion of patients. However, we have observed a long-term efficacy of the antiviral therapy in the sustained responders.


Assuntos
Antivirais/uso terapêutico , Hepatite C/prevenção & controle , Hepatite C/cirurgia , Transplante de Fígado , Quimioterapia Combinada , Seguimentos , Humanos , Interferon-alfa/uso terapêutico , Itália , Pacientes Desistentes do Tratamento , Recidiva , Estudos Retrospectivos , Ribavirina/uso terapêutico , Fatores de Tempo , Resultado do Tratamento , Carga Viral
4.
J Biotechnol ; 100(3): 277-86, 2003 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-12443859

RESUMO

Pancreatic rat islets are encapsulated by a siliceous layer deposited on the surface of single islets upon reaction with gaseous siliceous precursors. The process preserves original islet dimensions and does not suppress viability or function. The encapsulated material is homogeneously distributed on the islet surface, and layer thickness can be controlled in the 0.1-2.0 microm interval. Dynamic perfusion experiments with glucose stimulation were carried out in both encapsulated and non-encapsulated islets. Results were treated according to a kinetic model presented here for the analysis of perfusion data; the model tested by literature data, was used to substantiate the diffusion features of the siliceous layer, which does not affect mass transfer of insulin but which modifies the texture of the islet surface tissue. The clinical potential of silica encapsulation was demonstrated by in vivo experiments using encapsulated islets transplanted into diabetic rats. Transplantation was carried out in both inbred and outbred rats and indicated prolonged restoration of normal glycaemia levels and protection from immunological attack.


Assuntos
Diabetes Mellitus Experimental/cirurgia , Transplante das Ilhotas Pancreáticas/instrumentação , Ilhotas Pancreáticas/metabolismo , Membranas Artificiais , Dióxido de Silício , Animais , Materiais Biocompatíveis , Sobrevivência Celular , Simulação por Computador , Técnicas de Cultura , Diabetes Mellitus Experimental/metabolismo , Géis , Glucose/farmacologia , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/citologia , Transplante das Ilhotas Pancreáticas/métodos , Microesferas , Modelos Biológicos , Ratos , Ratos Endogâmicos Lew , Ratos Sprague-Dawley
5.
FEBS Lett ; 421(1): 50-4, 1998 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-9462838

RESUMO

Anti-HLA class I monoclonal antibody 01.65 inhibits the proliferative response of PHA-activated human T lymphocytes from peripheral blood mononuclear cells. The recruitment rate in the cell cycle is slack and the G1 and S phases are prolonged. Among the early events after PHA activation, only the calcium-dependent PKC activity appears to be modified: particulate PKC is completely depleted while cytosolic residual PKC is reduced by 80% after MAb 01.65 treatment. We have carried out in greater detail the study of c-myc gene regulation by MAb 01.65 and the results are as follows: (i) c-myc RNA transcription is normally initiated and finished, suggesting a post-transcriptional regulation of c-myc gene expression; (ii) no alteration in c-myc mRNA stability has been documented; (iii) steady-state levels of c-myc mRNA expression by Northern blot analysis and PCR amplification are decreased in the cytoplasmic compartment, while in the nuclear compartment they appear to be increased. Nuclear accumulation of mature mRNA after MAb 01.65 and PKC inhibitor (H7 and StSp) treatment appears to be the most probable mechanism involved. The possible implications of this are discussed.


Assuntos
Anticorpos Monoclonais/farmacologia , Núcleo Celular/metabolismo , Genes myc , Antígenos de Histocompatibilidade Classe I/imunologia , Ativação Linfocitária , Proteínas Proto-Oncogênicas c-myc/biossíntese , RNA Mensageiro/biossíntese , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transcrição Gênica , Sequência de Bases , Células Cultivadas , Primers do DNA , Éxons , Humanos , Fito-Hemaglutininas , Reação em Cadeia da Polimerase
6.
FEBS Lett ; 329(3): 324-8, 1993 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-8365475

RESUMO

A peptide inhibiting either corpuscolate or purified PKC has been identified from microsomes of PHA-activated human PBMC but it is not detectable in microsomes of resting PBMC. The peptide was obtained from a microsomal preparation in an oligomeric form that could be transformed into a monomeric form by beta-MSH. The active peptide (IN) was retained on a PC-11 chromatographic column and could be eluted with NaCl. IN is ineffective on PKC-dependent protamine phosphorylation of protamine and on Ca2+ and phospholipid-independent activity generated by mild hydrolysis with trypsin of PKC. Ca2+ binding is permissive for IN activity. IN inhibits particulate PKC in PHA-activated PBMC, but is ineffective after TPA activation. All these data indicate that IN acts at the regulatory domain of PKC.


Assuntos
Proteínas Sanguíneas/análise , Leucócitos Mononucleares/química , Microssomos/química , Proteína Quinase C/antagonistas & inibidores , Proteínas Sanguíneas/fisiologia , Células Cultivadas , Inibidores Enzimáticos/análise , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Fito-Hemaglutininas/farmacologia , Acetato de Tetradecanoilforbol/farmacologia
7.
Biochem Biophys Res Commun ; 188(1): 278-85, 1992 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-1417848

RESUMO

It is known that anti-HLA Class I antibodies inhibit the proliferative response of PHA-activated T-lymphocytes. We found that plastic- or sepharose-linked anti-HLA Class I monoclonal antibody 01.65 does not inhibit either [3H]Thymidine incorporation or recruitment in the cell cycle, nor does it reduce the expression of c-myc mRNA and the membrane expression of Interleukin-2 Receptor and Transferrin Receptor. Furthermore, particulate Protein Kinase C is not affected by anchored anti-HLA Class I monoclonal antibody 01.65. We suggest that anti-HLA Class I monoclonal antibody may act through crosslinking or internalization of HLA Class I antigens.


Assuntos
Anticorpos Monoclonais/farmacologia , Antígenos de Histocompatibilidade Classe I/imunologia , Ativação Linfocitária/imunologia , Linfócitos/imunologia , Anticorpos Monoclonais/imunologia , Ciclo Celular , Células Cultivadas , Humanos , Cinética , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/metabolismo , Fito-Hemaglutininas , Proteína Quinase C/metabolismo , Receptores de Interleucina-2/biossíntese , Receptores da Transferrina/biossíntese , Timidina/metabolismo
8.
Br J Haematol ; 81(2): 277-82, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1643025

RESUMO

The presence of mutations in the serine protease domain of protein C was investigated by temperature gradient gel electrophoresis of PCR products in five patients with protein C deficiency and thrombosis. Molecules with an altered melting behaviour were detected in one subject with a history of venous and arterial thrombosis. Direct sequencing showed that a G deletion, present in the heterozygous state, caused a reading frame shift at Trp 300 and subsequently a premature termination at the codon 335. The resulting suppression of the protein C catalytic function explains the reduction of protease activity to half. In addition the mutation caused a reduction of the antigen level in plasma. Temperature gradient gel electrophoresis enabled the rapid detection of the gene alteration in the family of the propositus. Several members of the paternal lineage had had severe thrombotic episodes. Unexpectedly the mutation was found to be inherited from the clinically asymptomatic maternal lineage, thus suggesting that an additional unknown defect from the paternal lineage is present in the thrombosis-prone propositus.


Assuntos
Mutação/genética , Proteína C/genética , Trombose/genética , Adulto , Sequência de Bases , Southern Blotting , Eletroforese em Gel de Poliacrilamida , Éxons , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase , Serina Endopeptidases/genética
9.
Br J Haematol ; 71(2): 271-6, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2493803

RESUMO

The presence of gene lesions in coagulation factor VIII (FVIII) gene was investigated in 70 Italian patients severely affected by haemophilia A. cDNA probes specific for exons 14-26 of the FVIII gene were used. In two related patients a gene deletion removes exon 26, a gene lesion similar to that described previously in a British haemophiliac. In exon 24 a C to T transition in the reverse complement strand causes a missense mutation in the coding strand (CGA----CAA, 2209 Arg----Gln). The mutation is located in a very conserved FVIII homology region and severely reduces FVIII activity. By restriction analysis and hybridizations with oligonucleotide probes this gene alteration was found in two unrelated haemophiliacs and in their relatives.


Assuntos
Deleção Cromossômica , Fator VIII/genética , Hemofilia A/genética , Mutação , Sondas de DNA , Éxons , Feminino , Humanos , Masculino , Sondas de Oligonucleotídeos , Mapeamento por Restrição
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