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1.
J Antimicrob Chemother ; 71(3): 739-50, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26679249

RESUMO

OBJECTIVES: This study aims to evaluate the reliability and clinical utility of NS3 sequencing in hepatitis C virus (HCV) 1-infected patients who were candidates to start a PI-containing regimen. METHODS: NS3 protease sequencing was performed by in-house-developed HCV-1 subtype-specific protocols. Phylogenetic analysis was used to test sequencing reliability and concordance with previous genotype/subtype assignment by commercial genotyping assays. RESULTS: Five hundred and sixty-seven HCV plasma samples with quantifiable HCV-RNA from 326 HCV-infected patients were collected between 2011 and 2014. Overall, the success rate of NS3 sequencing was 88.9%. The success rate between the two subtype protocols (HCV-1a/HCV-1b) was similarly high for samples with HCV-RNA >3 log IU/mL (>92% success rate), while it was slightly lower for HCV-1a samples with HCV-RNA ≤3 log IU/mL compared with HCV-1b samples. Phylogenetic analysis confirmed the genotype/subtype given by commercial genotyping assays in 92.9% (303/326) of cases analysed. In the remaining 23 cases (7.1%), 1 was HCV-1g (previously defined as subtype 1a), 1 was HCV-4d (previously defined as genotype 1b) and 1 was HCV-1b (previously defined as genotype 2a/2c). In the other cases, NS3 sequencing precisely resolved the either previous undetermined/discordant subtype 1 or double genotype/subtype assignment by commercial genotyping assays. Resistance-associated variants (RAVs) to PI were detected in 31.0% of samples. This prevalence changed according to PI experience (17.1% in PI-naive patients versus 79.2% in boceprevir/telaprevir/simeprevir-failing patients). Among 96 patients with available virological outcome following boceprevir/telaprevir treatment, a trend of association between baseline NS3 RAVs and virological failure was observed (particularly for HCV-1a-infected patients: 3/21 failing patients versus 0/22 achieving sustained virological response; P = 0.11). CONCLUSIONS: HCV-NS3 sequencing provides reliable results and at the same time gives two clinically relevant pieces of information: a correct subtype/genotype assignment and the detection of variants that may interfere with the efficacy of PI.


Assuntos
Farmacorresistência Viral , Técnicas de Genotipagem/métodos , Hepacivirus/classificação , Hepacivirus/efeitos dos fármacos , Hepatite C/virologia , Mutação , Proteínas não Estruturais Virais/genética , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Humanos , RNA Viral/genética , Estudos Retrospectivos , Análise de Sequência de DNA
2.
J Med Virol ; 85(6): 996-1004, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23588725

RESUMO

While the selection of complex HBV drug-resistance patterns on therapeutic failure can compromise the efficacy of anti-HBV therapies, recent data show that patients failing treatment without drug-resistance have a rate of virological success close to drug-naive patients. The goal of this study is defining, in clinical practice, the burden of drug-resistance mutations in a cohort of patients treated with anti-HBV drugs. Prevalence and patterns of drug-resistance were analyzed by RT-sequencing in 204 patients infected chronically: 148 experiencing virological rebound (defined as an increase in serum HBV-DNA > 20 IU/ml after achieving virological success [HBV-DNA < 20 IU/ml]), and 56 null/partial responders (always detectable serum HBV-DNA [>20 IU/ml] within 48 weeks of therapy). The highest rate of drug-resistance was observed in patients experiencing virological rebound (prevalence, 79.1%). Conversely, almost half (46.4%) null/partial responders have no evidence of drug-resistance. The rate of drug-resistance was higher in patients treated with lamivudine (76.8% [109/142]) and telbivudine (83.3% [5/6]), followed by adefovir (62.5% [15/24]), and entecavir (52.2% [12/23]). Complex mutational patterns characterized by the co-presence of rtM204V/I-rtA181T/V (impairing the efficacy of all anti-HBV drugs) were detected in four patients (2.7%) with virological rebound. Drug-resistance is the main cause of failure to therapy in patients experiencing virological rebound, supporting the need of rapid switch to anti-HBV drugs with higher genetic barrier and potency (entecavir/tenofovir). Conversely, nearly half of null/partial responders shows no evidence of drug-resistance mutations, maintaining high chance of achieving therapeutic success with the same class of drug. In this setting, genotypic resistance may help in selecting patients still carrying wild-type viruses, that may take major benefits from antiviral treatment.


Assuntos
Antivirais/uso terapêutico , DNA Viral/antagonistas & inibidores , Farmacorresistência Viral/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Mutação , Adenina/análogos & derivados , Adenina/uso terapêutico , Adulto , Estudos de Coortes , Farmacorresistência Viral/genética , Feminino , Guanina/análogos & derivados , Guanina/uso terapêutico , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Humanos , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Organofosfonatos/uso terapêutico , Recidiva , Telbivudina , Timidina/análogos & derivados , Timidina/uso terapêutico , Resultado do Tratamento
3.
Transpl Infect Dis ; 12(1): 11-5, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19744283

RESUMO

At the Tor Vergata University of Rome, ab initio calcineurin inhibitor-based monotherapy immunosuppression (IS) is the standard of treatment after liver transplantation (LT). As the net state of IS determines the onset of Pneumocystis jirovecii pneumonia (PCP), we hypothesized that, in the presence of weak impairment of the immune function, as determined by the above-mentioned IS, the host is not overexposed to the risk for PCP and consequently the specific anti-PCP prophylaxis is unnecessary. In a single-cohort descriptive study, we retrospectively investigated the incidence of PCP in 203 LT patients who did not receive anti-PCP prophylaxis because they were under monotherapy IS. The primary endpoint of the study was the incidence of PCP during the first 12 months following LT; secondary endpoints were the incidence of acute rejection requiring additional IS and of CMV infection. No cases of PCP were recorded. The incidence of CMV and acute rejection was 3.9% and 0.9%, respectively. Our data suggest that monotherapy IS after LT may nullify the risk for PCP even in the absence of any specific prophylaxis.


Assuntos
Inibidores de Calcineurina , Ciclosporina , Imunossupressores , Transplante de Fígado/efeitos adversos , Pneumocystis carinii/efeitos dos fármacos , Pneumonia por Pneumocystis/epidemiologia , Pneumonia por Pneumocystis/prevenção & controle , Tacrolimo , Adolescente , Adulto , Idoso , Ciclosporina/administração & dosagem , Ciclosporina/uso terapêutico , Feminino , Rejeição de Enxerto/epidemiologia , Humanos , Terapia de Imunossupressão , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Incidência , Masculino , Pessoa de Meia-Idade , Risco , Tacrolimo/administração & dosagem , Tacrolimo/uso terapêutico , Resultado do Tratamento , Adulto Jovem
4.
Minerva Gastroenterol Dietol ; 56(1): 87-91, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20190729

RESUMO

The authors describe an unusual complication after radiofrequency ablation of hepatocellular carcinoma (HCC). An 84-year old man, already operated of right hepatectomy for HCC, underwent radiofrequency ablation (RFA) of a new focal hepatic lesion in IV segment, under ultrasound (US) and computed tomography (CT) guidance. The procedure was carried out without any special difficulties or complications. Seven days later, the patient suddenly complained epigastric pain, progressive jaundice and sleepiness and an increase in cholestasis sierological parameters. A CT scan revealed thrombosis of the left side branch of the portal vein, with moderate bile ducts distension. The case described demonstrates how RFA may cause thermally mediated damage of the surrounding structures, due to unpredictable radio-frequency propagation. The interest of this case report is due to the fact that portal vein thrombosis did not occur immediately after the procedure, it happened without direct vessel injury by the needle and involved a vessel greater than 3 mm.


Assuntos
Ablação por Cateter/efeitos adversos , Veia Porta , Trombose/etiologia , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/cirurgia , Humanos , Neoplasias Hepáticas/cirurgia , Masculino
5.
Clin Microbiol Infect ; 25(7): 906.e1-906.e7, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30472417

RESUMO

OBJECTIVE: We aimed to investigate HBx genetic elements correlated with hepatitis B virus (HBV) -related hepatocellular carcinoma (HCC) and their impact on (a) HBV replicative efficiency, (b) HBx binding to circular covalently closed DNA (cccDNA), (c) apoptosis and cell-cycle progression, and (d) HBx structural stability. METHODS: This study included 123 individuals chronically infected with HBV: 27 with HCC (77.9% (21/27) genotype D; 22.1% (6/27) genotype A) and 96 without HCC (75% (72/96) genotype D; 25.0% (24/96) genotype A). HepG2 cells were transfected by wild-type or mutated linear HBV genome to assess pre-genomic RNA (pgRNA) and core-associated HBV-DNA levels, HBx-binding onto cccDNA by chromatin immunoprecipitation-based quantitative assay, and rate of apoptosis and cell-cycle progression by cytofluorimetry. RESULTS: F30V was the only HBx mutation correlated with HCC (18.5% (5/27) in HCC patients versus 1.0% (1/96) in non-HCC patients, p 0.002); a result confirmed by multivariate analysis. In vitro, F30V determined a 40% and 60% reduction in pgRNA and core-associated HBV-DNA compared with wild-type (p <0.05), in parallel with a significant decrease of HBx binding to cccDNA and decreased HBx stability. F30V also decreased the percentage of apoptotic cells compared with wild-type (14.8 ± 6.8% versus 19.1 ± 10.1%, p <0.01, without affecting cell-cycle progression) and increased the probability of HBx-Ser-31 being phosphorylated by PI3K-Akt kinase (known to promote anti-apoptotic activity). CONCLUSIONS: F30V was closely correlated with HBV-induced HCC in vivo, reduced HBV replicative efficiency by affecting HBx-binding to cccDNA and increased anti-apoptotic HBx activity in vitro. This suggests that F30V (although hampering HBV's replicative capacity) may promote hepatocyte survival, so potentially allowing persistent production of viral progeny and initiating HBV-driven hepatocarcinogenesis. Investigation of viral genetic markers associated with HCC is crucial to identify those patients at higher risk of HCC, who hence deserve intensive liver monitoring and/or early anti-HBV therapy.


Assuntos
Apoptose , Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/genética , Neoplasias Hepáticas/virologia , Transativadores/genética , Replicação Viral , Adulto , Idoso , DNA Viral/genética , Feminino , Genótipo , Células Hep G2 , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/virologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Homologia Estrutural de Proteína , Transativadores/química , Proteínas Virais Reguladoras e Acessórias
6.
Am J Transplant ; 8(3): 673-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18294164

RESUMO

Hepatitis C virus (HCV) re-infection after liver transplantation (LT) is characterized by an accelerated disease progression in recent years with unclear mechanisms. We evaluate the relationship between progression of liver fibrosis and histological necro-inflammation in HCV recipients, according to age of transplant. Fifty-five patients transplanted (1993-2002) for HCV liver disease, were included in the study. Recipients were retrospectively stratified in three different age of transplant, of 40 months each: group 1) from January 1993 to May 1996; group 2) from June 1996 to august 1999; group 3) from September 1999 to December 2002. Grading (necro-inflammation) and staging (fibrosis) scores were evaluated in liver biopsies at 1, 2 and 3 years from LT (Ishak classification). For all age of transplant the main factor associated with fibrosis progression, was grading score (p < 0.05). However mean staging score for each point of grading increased from 0.3 +/- 0.2 in older LT to 0.7 +/- 0.5 in newer ones (p = 0.01). In conclusion in HCV-LT patients (1) liver fibrosis is strictly associated to histological necro-inflammation; (2) the proportion of this relationship has been changing in recent years since newer LT patients, show an increased amount of fibrosis in comparison with the older ones, for similar grading score.


Assuntos
Hepatite C Crônica/patologia , Hepatite C Crônica/cirurgia , Cirrose Hepática/patologia , Cirrose Hepática/cirurgia , Transplante de Fígado , Fatores Etários , Progressão da Doença , Feminino , Hepacivirus/isolamento & purificação , Hepatite C Crônica/complicações , Humanos , Terapia de Imunossupressão , Inflamação/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Recidiva
7.
Dig Liver Dis ; 38(10): 749-54, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16916630

RESUMO

BACKGROUND: The recommended prophylaxis against hepatitis B virus recurrence after liver transplantation based on hepatitis B immunoglobulins and lamivudine is highly expensive. A recent study reported a significant anti-HBs (antibodies against hepatitis B surface antigen) response after a reinforced vaccination against hepatitis B virus, a result not confirmed in a study from our group. Concomitant lamivudine treatment and the achievement of complete washout of anti-hepatitis B-specific immunoglobulin prior to vaccination in our study could explain the contradiction. AIMS: To test the efficacy of a reinforced anti-hepatitis B virus vaccination schedule without lamivudine and without previous anti-hepatitis B-specific immunoglobulin washout. METHODS: A double reinforced course of S-recombinant hepatitis B virus vaccination was given to seven male patients who were transplanted for hepatitis B virus-related cirrhosis. Vaccination consisted of two cycles of three intramuscular double doses (40 microg), given at month 0, 1, 2, and 3, 4, 5, respectively. The first dose was given 2 weeks after stopping lamivudine and the intravenous administration of anti-HBs immunoglobulins. The latter was continued throughout the study and follow-up period to maintain an anti-HBs titre >100 IU/L. RESULTS: At the end of both the first and the second vaccination cycle none of the patients developed an anti-HBs titre greater than the basal anti-HBs titre. CONCLUSION: These data confirm and expand our previous data on the lack of effectiveness of conventional recombinant hepatitis B virus vaccination in liver transplant recipients.


Assuntos
Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/imunologia , Hepatite B/prevenção & controle , Transplante de Fígado/imunologia , Adulto , Vacinas contra Hepatite B/administração & dosagem , Humanos , Imunoglobulinas/uso terapêutico , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Inibidores da Transcriptase Reversa/uso terapêutico
8.
Biochim Biophys Acta ; 905(1): 91-9, 1987 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-3676319

RESUMO

The hepatic uptake, transport and utilization of plasma lysophosphatidylcholine (lysoPC) and its contribution to biliary lipid secretion have been investigated in bile-fistula rats. The animals were given a single intravenous dose of sn-1-[1-14C]palmitoyl-lysoPC, under constant intravenous sodium taurocholate infusion (1 mumol/min), and the fate of the label was followed in blood, bile and liver for up to 3 h. The livers were excised at given time points, extracted and/or homogenized to determine the lipid distribution and subcellular location of radioactivity. LysoPC was rapidly cleared from plasma, though a consistent fraction of the label persisted in plasma over the experimental time-period in the form of either lysoPC or PC. Recovery of radioactivity in the liver varied from 15.6% after 5 min to 19.5% after 3 h. Hepatic lysoPC underwent rapid microsomal acylation to form specific PC molecular species (mainly 16:0-20:4 and, to a lesser extent, 16:0-18:2 and 16:0-16:1). Ultrafiltration, dialysis and gel-chromatographic analyses of cytosolic fractions (post 105,000 X g supernatants) indicated that lysoPC is transported to the site of acylation mostly as a macromolecular aggregate with an approx. Mr of 14,400. Small amounts of radioactivity were secreted into bile over 3 h (20% in the form of lysoPC and the remainder as 16:0-18:2 and 16:0-20:4 PC species). Plasma lysoPC, taken up by the liver, is mostly transported by a cytosolic carrier with a molecular weight close to fatty-acid-binding proteins; it then enters a distinct acylation pathway, selective for some polyunsaturated-PC species and does not contribute significantly to biliary secretion, either directly, or through its products.


Assuntos
Bile/metabolismo , Lisofosfatidilcolinas/metabolismo , Animais , Transporte Biológico , Cromatografia Líquida de Alta Pressão , Citosol/química , Fígado/metabolismo , Masculino , Ratos , Ratos Endogâmicos , Frações Subcelulares/química
9.
Biochim Biophys Acta ; 1086(1): 125-33, 1991 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-1954239

RESUMO

We compared the protein/lipid structure and Ch-nucleating capacity of individual lipid carriers in two groups of human gallbladder biles: 11 with Fast cholesterol nucleation (2.2 +/- 1.3 days) and 10 with Slow cholesterol nucleation (19.2 +/- 4.4 days). The groups had comparable cholesterol-saturation (1.31 vs. 1.28), total lipids (9.9 vs. 8.5 g/dl) and proteins (8.5 vs. 7.6 mg/ml). Bile was ultracentrifuged (2 h at 150,000 x g) and the resulting isotropic phase was incubated with [3H]Ch and [14C]lecithin and gel-chromatographed on a Superose 6 column with a buffer containing 7.0 mM sodium-taurocholate. Seven protein peaks were identified (280 nm and biochemistry), with the following molecular mass ranges (kDa): 1 (Void volume), 2 (155-205), 3 (50-79), 4 (20-29), 5 (6-15), 6 (3.5-6), 7 (2-3.5). Peaks 2 and 3 were identified as vesicles and micelles, respectively. Fast vs. Slow Ch nucleating biles had: (a) more (P less than 0.02) cholesterol coeluting with vesicles, (b) more (P less than 0.01) lecithin coeluting with low m.w. peaks (Nos. 5-6), (c) less (P less than 0.01) cholesterol and lecithin coeluting with micelles. An inverse correlation (P less than 0.001) was observed between the amount of proteins coeluting with the micellar peak and the cholesterol nucleation of both whole bile and isolated micellar fractions. A marked shift of cholesterol and lecithin from micelles to vesicles was apparent, in the whole bile, after cholesterol nucleation had occurred. Incubation and sequential analysis of isolated and radiolabeled micelles showed a progressive transfer of lecithin and cholesterol molecules to low molecular weight fractions and to vesicles before cholesterol nucleation. We conclude that pro-nucleating biliary vesicles develop from micelles, due to the phasing out and redistribution of micellar cholesterol and lecithin, which are probably induced by biliary proteins.


Assuntos
Bile/química , Colesterol/química , Lipídeos/química , Proteínas/química , Adulto , Idoso , Cromatografia em Gel , Cristalização , Feminino , Humanos , Cinética , Lipídeos/análise , Masculino , Micelas , Pessoa de Meia-Idade , Proteínas/análise
10.
Biochim Biophys Acta ; 1214(1): 63-72, 1994 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-8068730

RESUMO

Crystal observation time is a rough estimate of the first microscopic appearance of cholesterol monohydrate crystals in an isotropic bile, and does not provide information on crystal growth kinetics. We have developed a method for quantitating cholesterol crystal growth in gallbladder bile. Crystals were separated from other biliary particles by ultracentrifugation on a discontinuous NaBr gradient, after bile density adjustment to d = 1.060 g/ml. More than 95% of crystals, both of native or synthetic source, floated in the density range 1.045-1.055. This density fraction was collected and crystal mass was measured by photometric turbidity, after calibration with suspensions of different-sized cholesterol crystals. The recovery of crystals added to original bile samples averaged 96.0 +/- 2.8%. Contamination with vesicles, which may potentially interfere with the turbidimetric assay, was excluded by gel-chromatography. The method was sequentially applied, until the 20th day of incubation, to biles obtained at surgery from patients with (A, n = 6) or without cholesterol gallstone (B, n = 4), and from gallstone patients pretreated for 1 week with oral ursodeoxycholic acid (C, n = 5). Crystal growth curves greatly differed, being much steeper in group A and almost flat in patients receiving ursodeoxycholic acid. The mean percent mass of biliary cholesterol in crystalline form at the 20th day was 19.2 +/- 13.5%, 1.2 +/- 0.8% and 2.7 +/- 1.1% in A, B and C, respectively (A vs. B: P = 0.014; A vs. C: P = 0.008). We conclude that the method allows a precise estimate of cholesterol crystal growth and can be usefully applied to human gallbladder biles.


Assuntos
Bile/química , Colesterol/química , Vesícula Biliar/metabolismo , Centrifugação com Gradiente de Concentração , Ácido Quenodesoxicólico/farmacologia , Colelitíase/metabolismo , Colesterol/isolamento & purificação , Cristalização , Humanos , Cinética , Nefelometria e Turbidimetria , Espectrofotometria , Ácido Ursodesoxicólico/farmacologia
11.
Biochim Biophys Acta ; 1006(1): 116-20, 1989 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-2804062

RESUMO

The content of polyunsaturated phosphatidylcholines (PCs) is one of the parameters which regulate membrane functions. Polyunsaturated PCs are preferentially synthesized in the liver by the microsomal enzyme phosphatidylethanolamine N-methyltransferase. The activity of this enzyme may be stimulated in vitro in isolated rat hepatocytes by supplementation with dimethylethanolamine (DME), the polar head group of the precursor of PC along this pathway. The aim of this study was to evaluate in vivo the effect of an intravenous infusion of DME in the rat on the hepatic phospholipid composition. Bile fistula rats were intravenously infused for 15 h with sodium taurocholate (1 mumol/kg per min), with or without the addition of 0.3 mg/kg per min of [14C]DME. The concentration per gram of wet liver of individual phospholipid classes, PC molecular species and of total triacylglycerols, as well as the distribution of radioactivity in liver phospholipids, in rat tissues and body fluids were analyzed. A significant (P less than 0.01) enrichment in PC was found in the liver of DME-infused rats with respect to controls. No differences in the other phospholipid classes were found. DME-infused rats showed a significant (P less than 0.01) decrease in the hepatic concentration of triacylglycerols. At HPLC analysis, the enrichment in PC in DME-infused rats was found to be selectively due to three molecular species (i.e., sn-1 stearoyl/sn-2 arachidonoyl, sn-1 stearoyl/sn-2 linoleoyl, sn-1 stearoyl/sn-2 docosahexanoyl molecular species). In agreement with quantitative data, more than 70% of hepatic radioactivity was recovered in polyunsaturated PC species, with the highest specific activity in the sn-1 stearoyl PCs. The specific activity of hepatic PC approximates that of phosphatidyldimethylethanolamine. This finding together with the effective incorporation of DME in PC suggests that this amino base is methylated after its incorporation into phosphatidyldimethylethanolamine, throughout the stimulation of hepatic N-methyltransferase activity. The selective hepatic enrichment with polyunsaturated PC species after DME infusion may offer a new experimental tool for studying hepatic membrane metabolism.


Assuntos
Deanol/farmacologia , Etanolaminas/farmacologia , Ácidos Graxos Insaturados/metabolismo , Fígado/metabolismo , Fosfatidilcolinas/metabolismo , Animais , Fígado/efeitos dos fármacos , Masculino , Fosfolipídeos/metabolismo , Ratos , Ratos Endogâmicos , Triglicerídeos/metabolismo
12.
Biochim Biophys Acta ; 878(2): 216-24, 1986 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-3756193

RESUMO

Studies were carried out using an isolated rat liver system to define: the contribution of exogenous phosphatidylcholine (PC) to biliary phospholipid secretion; and its hepatic metabolism during perfusion of the livers with conjugated bile salts with different hydrophilic/hydrophobic properties. A tracer dose of sn-1-palmitoyl-sn-2-[14C]linoleoylPC was injected as a bolus into the recirculating liver perfusate, under constant infusion of 0.75 mumol/min of tauroursodeoxycholate or taurodeoxycholate. The effects on bile flow, biliary lipid secretion, 14C disappearance from the perfusate and its appearance in bile, as well as hepatic and biliary biotransformation were determined. With both the bile salts, about 40% of the [14C]PC was taken up by the liver from the perfusate over 100 min. During the same period less than 2% of the given radioactivity was secreted into bile. More than 95% of the 14C recovered in bile was located within the identical injected PC molecular species. The biliary secretion of labeled as well as unlabeled PC, however, was significantly higher in livers perfused with taurodeoxycholate than tauroursodeoxycholate, while the reverse was observed with respect to bile flow and total bile salt secretion. The exogenous PC underwent extensive hepatic metabolization which appeared to be influenced by the type of bile salt perfusing the liver. After 2 h perfusion, the liver radioactivity was found, in decreasing order, in PC, triacylglycerol, phosphatidylethanolamine and diacylglycerol. In addition, the specific activity of triacylglycerol was significantly higher in tauroursodeoxycholate than in taurodeoxycholate-perfused livers (P less than 0.025), while the reverse was true for the specific activity of hepatic PC (P less than 0.01). Because taurodeoxycholate and tauroursodeoxycholate showed opposite effects on both biliary lipid secretion and hepatic PC biotransformations, we conclude that the hepatic metabolism of glycerolipids is influenced by the physiochemical properties of bile salts.


Assuntos
Bile/metabolismo , Ácido Quenodesoxicólico/análogos & derivados , Ácido Desoxicólico/análogos & derivados , Fígado/metabolismo , Fosfatidilcolinas/metabolismo , Ácido Tauroquenodesoxicólico/farmacologia , Ácido Taurodesoxicólico/farmacologia , Animais , Radioisótopos de Carbono , Técnicas In Vitro , Fígado/efeitos dos fármacos , Masculino , Perfusão , Ratos , Ratos Endogâmicos , Triglicerídeos/metabolismo
13.
Diabetes ; 44(3): 295-9, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7883117

RESUMO

Offspring of mothers with insulin-dependent diabetes mellitus (IDDM) have a much lower risk of IDDM than do offspring of diabetic fathers, and this risk is particularly low for offspring born to diabetic mothers over the age of 25 years. To determine whether increasing maternal age also protects the offspring of IDDM fathers from IDDM, we surveyed 367 IDDM fathers (IDDM onset before age 35) who first came to the Joslin Clinic (Boston, MA) between 1945 and 1969. Of the 840 offspring of these men, IDDM developed in 28 before the age of 20, giving a cumulative risk of 5.1 +/- 1.0% (means +/- SE). Because this is similar to the result of our earlier study of IDDM fathers, the two groups were combined to give 1,084 offspring, 39 having IDDM (cumulative risk of IDDM 5.4 +/- 0.9% by age 20), for comparison with our cohort of 1,391 offspring of 739 IDDM mothers. In that cohort, IDDM developed in 20 offspring before the age of 20 years, giving a cumulative risk of 2.1 +/- 0.5%. The risk of diabetes in offspring was higher if the parent's IDDM was diagnosed before age 11 than if it was diagnosed later: 9.3 compared with 4.0% (P = 0.006) for the offspring of IDDM fathers and 2.7 compared with 1.8% for the offspring of IDDM mothers (P = 0.06). In the families in which the father's IDDM was diagnosed after age 11, a protective effect of maternal age > or = 25, similar to that in families of IDDM mothers, seems to be present.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/genética , Aborto Espontâneo , Adolescente , Adulto , Idade de Início , Criança , Estudos de Coortes , Diabetes Mellitus Tipo 1/prevenção & controle , Pai , Feminino , Morte Fetal , Seguimentos , Humanos , Masculino , Idade Materna , Pessoa de Meia-Idade , Gravidez , Fatores de Risco , Inquéritos e Questionários
14.
Diabetes ; 46(12): 1983-9, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9392484

RESUMO

Eight type 1 diabetic patients, ages 29-41 years, with mean diabetes duration of 23 years (range 18-29 years) received islet transplants from 1 to 5 donors. Seven patients had stable kidney allografts 1-11 years before the islet transplant, and one patient had a simultaneous islet-kidney allograft. Patients' blood glucose control was poor as reflected by the mean +/- SD HbA1c of 9.1 +/- 1.7% before transplant. Of the first three patients, two (1 and 3) achieved insulin independence for 36 and 38 days, respectively. Two recipients rejected their islet grafts within 1 month (2 and 8) and therefore were excluded from analysis. The HbA1c and insulin requirement of the six remaining patients who had persistent islet function for more than 60 days was significantly reduced from 9.3 +/- 1.9 to 6.4 +/- 1.0% (P = 0.002) and from 0.75 +/- 0.15 to 0.35 +/- 0.12 U x kg(-1) x day(-1) (P < 0.001), respectively. The two patients with the longest graft survival (4 and 6) achieved a normalization or near-normalization of their HbA1c levels during 6 years in the absence of severe episodes of hypoglycemia. As demonstrated by a decline in C-peptide response during Sustacal challenge tests over a 6-year period, there was a diminution of islet allograft function over time, despite persistence of normal or near normal HbA1c. We concluded that transplantation of allogeneic islets with an islet mass comparable with whole or segmental pancreas transplants in type 1 diabetic patients can result in long-term islet allograft function; further, we concluded that, in conjunction with small dosages of exogenous insulin, a functioning islet allograft can result in near-normalization of blood glucose levels and significant improvement in HbA1c. The occurrence of severe hypoglycemic episodes observed for patients in the Diabetes Control and Complications Trial was not observed in recipients with functioning islet transplants, despite the continuous need for exogenous insulin therapy to sustain normal HbA1c over the 6-year follow-up. The significant improvement in metabolic control observed for the patients described in this study, and the potential to significantly decrease or halt the progression of diabetic complications, support the continued application of islet allotransplantation as a treatment modality for type 1 diabetic patients.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas , Adulto , Glicemia/metabolismo , Peptídeo C/sangue , Técnica Clamp de Glucose , Hemoglobinas Glicadas/metabolismo , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Insulina/sangue , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Transplante de Rim , Taxa de Depuração Metabólica , Fatores de Tempo , Transplante Homólogo
15.
Dig Liver Dis ; 37(7): 461-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15893508

RESUMO

Liver transplantation is an efficient procedure as performed in Italy, yet major differences are present in terms of practice. In an effort to facilitate an homogeneous practice of liver transplantation in Italy, the Italian Association for the Study of Liver Disease has instituted a Commission aimed at providing recommendations on non-urgent liver transplantation in adults, based on current evidence. This nation-wide commission which included experienced hepatologists, surgeons and pathologists with major interest in liver transplantation has drafted a final document in October 2004, approved by the Italian Association for the Study of Liver Governing Board, whose key arguments and main conclusions are summarised in the present paper. The Commission has made specific recommendations on the following topics: the current needs of liver transplantation in Italy; the indications to liver transplantation and re-liver transplantation, with special reference to controversial issues and the minimal listing criteria; the use of marginal donors and the need to optimise donor/recipient matching; the use of living donor liver transplantation; the management of the waiting list and the introduction of Model for End-Stage Liver Disease to define priorities; the clinical management of liver transplantation recipients and disease recurrence; the implementation of audits and outcome monitoring; the training of transplant surgeons and hepatologists and the requirements for Centre accreditation; the pathology of liver transplantation.


Assuntos
Transplante de Fígado , Humanos , Itália , Transplante de Fígado/imunologia , Doadores Vivos , Reoperação , Obtenção de Tecidos e Órgãos/organização & administração , Listas de Espera
16.
Dig Liver Dis ; 37(10): 793-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16024302

RESUMO

The effectiveness of hepatitis B virus vaccination in liver transplant recipients for hepatitis B virus-related end-stage liver disease is controversial. We report two successful cases, who developed sustained protection after long-term vaccination. Case 1. A 58-year-old male, transplanted 9 years earlier, received three intramuscular monthly doses of 40 microg of recombinant S vaccine and developed an anti-hepatitis B surface titre of 154 IU/L. After an additional 40 microg dose, he reached an anti-hepatitis B surface peak of 687 IU/L and then maintained a "protective" titre (>100 IU/L) without further vaccinations for the next 40 months. At this time, revaccination with three monthly doses of 40 microg resulted in an anti-hepatitis B surface titre greater than 25,000 IU/L, sustained over time. Case 2. A 56-year-old woman, transplanted 8 years earlier, first received three intramuscular monthly doses of 40 microg of S vaccine without developing any detectable anti-HBs. She was then given multiple intradermal vaccine doses which resulted in a titre of 37 IU/L. Next, after readministration of three 40 microg intramuscular monthly doses, she developed an anti-HBs titre of 280 IU/L. In the following 4 years, the anti-HBs titre dropped below 100 IU/L four times (at month 20, 30, 38 and 44) and readministration of single 40 microg doses of vaccine was always sufficient to restore a protective titre. Conclusion. Extended HBV vaccination may afford valid protection against HBV recurrence in selected liver transplant recipients.


Assuntos
Vacinas contra Hepatite B/uso terapêutico , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/complicações , Hepatite B/terapia , Cirrose Hepática/terapia , Cirrose Hepática/virologia , Transplante de Fígado , Feminino , Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Vírus da Hepatite B/imunologia , Humanos , Falência Renal Crônica/cirurgia , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Vacinas Sintéticas/uso terapêutico
17.
J Mol Med (Berl) ; 77(1): 144-7, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9930950

RESUMO

Most patients with cirrhosis of the liver have detectable insulin resistance. In 60-80% of patients with cirrhosis, impaired glucose tolerance can be uncovered; approximately 20% of these patients eventually develop overt diabetes. Theoretically, insulin resistance and glucose intolerance could be improved or reversed by orthotopic liver transplantation alone or in association with a simultaneous transplant of pancreatic islet cells from the same donor. To investigate these possibilities we initiated a pilot study of simultaneous liver and pancreatic islet cell transplantation in seven patients with diabetes and liver cirrhosis. Donor bone marrow cells were also infused to enhance the acceptance of the grafts. Seven patients who received only orthotopic liver transplantation and donor bone marrow cells were used as historical controls. The preliminary results of this pilot trial suggest that islet cell transplantation in conjunction with orthotopic liver transplantation improves glucose metabolism in patients with liver cirrhosis in association with reduced insulin requirements and HbA1c levels. These results were evident in spite of pre- and post-transplant basal C-peptide levels that were unchanged. Further evaluation of the effects of orthotopic liver transplantation with or without islet cell transplantation will require a randomized prospective trial including accurate metabolic evaluation with the euglycemic insulin clamp technique.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas , Cirrose Hepática/cirurgia , Transplante de Fígado , Adolescente , Adulto , Idoso , Criança , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Transplante Homólogo
18.
Eur Rev Med Pharmacol Sci ; 9(5): 295-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16231593

RESUMO

Early graft dysfunction develops in up to 10-50% of liver transplanted patients and is related to the number of risk factors which identify marginal livers. Marginal livers are defined by the presence of af least one of the following risk factors: (1) donor aged > 50 years; (2) donor with hemodynamic instability or with a residence time in ICU greater than 5 days; (3) donor with hypersodiemia; (4) donor with HCV or HBV infection; and (5) donor with macrovescicular steatosis present in > 25% of hepatocytes. The presence of steatosis involving less than 25% of hepatocytes is not considered sufficient to identify a marginal donor, although it may be associated with some risk of early or late graft failure. The reason is that the steatotic liver is characterized by a decreased tolerance to ischemia/reperfusion. It has been observed that the accumulation of fat in the hepatocytes and the increased cell volume cause an impairment of liver microcirculation. Steatosis is associated with decreased capability of ATP production and storage, with increased lipid peroxidation, and with increased release of tumor necrosis factor-a which is believed to be responsible of the lung damage possibly occurring after transplant. The assessment of the type and extent of steatosis requires liver biopsy, not usually indicated in healthy individual. In the transplant setting a precise assessment of steatosis is the prominent reason for performing a liver biopsy of the donor liver.


Assuntos
Fígado Gorduroso/patologia , Sobrevivência de Enxerto , Transplante de Fígado , Fígado/patologia , Biópsia , Humanos , Fígado/cirurgia , Transplantes
19.
Transplant Proc ; 37(6): 2629-31, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16182768

RESUMO

A 37-year-old male liver transplant recipient developed hemorrhagic shock from massive rectal bleeding a few hours after a protocol liver biopsy. Conservative treatment was not possible and the patient underwent a radiological investigation of the celiac and mesenteric arterial trunks, which showed active bleeding from a branch of the middle colic artery. Embolization with Tabotamp (Ethicon, Neuchatel, CH Switzerland) particles led to successful hemostasis. We thus discuss the possible mechanisms of injury. To our knowledge, no other cases of major rectal bleeding following percutaneous liver biopsy have been reported in the literature. We emphasize the need for Doppler ultrasound assistance, in terms of either preoperative examination with or without marking or guidance. The latter is the safest and most reliable technique, given the low risk of puncture of other organs and the low probability of obtaining an inadequate sample.


Assuntos
Biópsia/efeitos adversos , Colo/anatomia & histologia , Hemorragia Gastrointestinal/etiologia , Transplante de Fígado/patologia , Fígado/anatomia & histologia , Doenças Retais/etiologia , Choque Hemorrágico/etiologia , Adulto , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemorragia Gastrointestinal/patologia , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Doenças Retais/diagnóstico por imagem , Doenças Retais/patologia , Ultrassonografia Doppler
20.
Transplant Proc ; 37(4): 1705-7, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15919438

RESUMO

BACKGROUND: Recurrent hepatitis C virus (HCV) infection is universal after liver transplantation (LT), yet no effective therapy is available. Amantadine (Am) is currently under evaluation. The aim of this study was to assess the safety and the effectiveness of Am monotherapy in LT patients with HCV recurrence. METHODS: Twelve patients who underwent transplantation 1-4 years earlier were included when there was detectable serum HCV-RNA and histological signs of liver damage with evidence of progressive hepatic fibrosis. Basal Ishak's scores were 2.1 +/- 1.3 and 5.1 +/- 2.7, respectively. Exclusion criteria were histological cirrhosis and comorbidities. All patients were receiving cyclosporine, with or without azathioprine. Amantadine was given orally (200 mg/d) for 3 months. RESULTS: Eight (67%) patients completed a 3-month treatment course without dose adjustments. Am was reduced to 100 mg/d in 3 cases and withdrawn in 1 due to side effects, namely, insomnia (n = 7; 58%), tremor (n = 4; 33%), headache (n = 2; 17%), asthenia (n = 2; 17%), and dermatitis, diarrhea, and increased creatinine (each n = 1; 8%). Serum HCV-RNA levels decreased in 3 patients, increased in 3, and remained unchanged in the others. Alanine aminotransferase (ALT) remained abnormal in all cases. Liver function test results did not improve. CONCLUSIONS: Short-term Am monotherapy was ineffective to treat post-LT HCV relapse and was associated with significant side effects.


Assuntos
Amantadina/uso terapêutico , Antivirais/uso terapêutico , Hepatite C/prevenção & controle , Transplante de Fígado , Azatioprina/uso terapêutico , Ciclosporina/uso terapêutico , Feminino , Humanos , Imunossupressores/uso terapêutico , Testes de Função Hepática , Transplante de Fígado/imunologia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Recidiva , Reprodutibilidade dos Testes , Falha de Tratamento , Carga Viral
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