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1.
Artigo em Inglês | MEDLINE | ID: mdl-34874844

RESUMO

Life-long immunosuppression has always been considered the key in managing liver graft protection from recipient rejection. However, it is associated with severe adverse effects that lead to increased morbidity and mortality, including infections, cardiovascular diseases, kidney failure, metabolic disorders and de novo malignancies. This explains the great interest that has developed in the concept of tolerance in recent years. The liver, thanks to its marked tolerogenicity, is to be considered a privileged organ: up to 60% of selected patients undergoing liver transplantation could safely withdraw immunosuppression.


Assuntos
Transplante de Fígado , Rejeição de Enxerto/prevenção & controle , Humanos , Tolerância Imunológica , Terapia de Imunossupressão , Imunossupressores/efeitos adversos , Transplante de Fígado/efeitos adversos
2.
Transplant Proc ; 50(1): 175-183, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29407305

RESUMO

AIM: We designed a retrospective case-control study to determine the efficacy and feasibility of everolimus (EVR) combined with low-dose tacrolimus (Tac) ab initio versus standard-dose Tac after liver transplantation (LT). METHODS: Seventy-one adult LT patients, receiving EVR and low-dose Tac without corticosteroids or induction therapy from postoperative day 1 (EVR group) were compared with a well-matched control group of 61 recipients treated with standard-dose Tac in association with antimetabolite. RESULTS: Baseline characteristics for the two groups were comparable. The overall patient and graft survival rates were similar (P = .908). Liver function was stable during the follow-up. In the EVR group, biopsy-proven acute rejection occurred in two cases (2.8%), whereas chronic rejection occurred in one (1.4%). The EVR group experienced a better renal function already after 2 weeks (estimated glomerular filtration rate: 89.85 [36.46 to 115.3] mL/min/1.73 m2 vs. 68.77 [16.11 to 115.42] mL/min/1.73 m2; P = .013), which was also observed after a median time of 27 months (range, 0 to 82 months) from LT (estimated glomerular filtration rate: 80 [45 to 118.3] mL/min/1.73 m2 vs. 70.9 [45 to 88.4] mL/min/1.73 m2; P = .04). After a median time of 27 months, the EVR group showed lower incidence of arterial hypertension and insulin-dependent diabetes mellitus. CONCLUSION: Ab initio EVR-based immunosuppression could be a valid option immediately after surgery in recipients at high-risk for post-LT renal impairment.


Assuntos
Everolimo/administração & dosagem , Terapia de Imunossupressão/métodos , Imunossupressores/administração & dosagem , Transplante de Fígado/métodos , Tacrolimo/administração & dosagem , Adulto , Idoso , Biópsia , Inibidores de Calcineurina/administração & dosagem , Estudos de Casos e Controles , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/etiologia , Quimioterapia Combinada , Estudos de Viabilidade , Feminino , Taxa de Filtração Glomerular , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Hipertensão/epidemiologia , Hipertensão/etiologia , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Tempo
3.
Eur J Surg Oncol ; 35(5): 486-91, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19171450

RESUMO

BACKGROUND: The treatment of hepatic metastases from gastric cancer is controversial, due to biologic aggressiveness of the disease. OBJECTIVE: To survey the clinical approach to the subset of patients presenting with metachronous hepatic metastases as sole site of recurrence after curative resection of gastric cancer, focusing on the results achieved by different therapies and to investigate the prognostic factors of major clinical relevance. METHODS: Retrospective multi-center chart review evaluating 73 patients, previously submitted to D >or= 2 gastrectomy for gastric cancer, who developed exclusive hepatic recurrence. Prognostic factors related to the patient, to the gastric malignancy and its treatment, and to the metastatic disease and its therapy were evaluated. RESULTS: Forty-five patients received supportive care, 17 were submitted to chemotherapy, and 11 to hepatic resection. Survival was independently influenced by the variables T (p=0.019), N (p=0.05) and G (p=0.018) of the gastric primary and by the therapeutic approach to the metastases (p<0.005). In particular, T4 gastric cancer, presence of lymph-node metastases and G3 tumor displayed a negative prognostic value. Therapeutic approach to the metastases was the principal prognostic variable: 1, 2, and 3 years survival rates were 22.2%, 4.4% and 2.2%, respectively, for patients without specific treatment; 44.9%, 12.8% and 6.4% after chemotherapy (p=0.08) and 80.8%, 30.3% and 20.2% after surgical resection (p<0.001). CONCLUSIONS: Our data suggest some clinical criteria that may facilitate selection of therapy for patients with hepatic recurrence after primary gastric cancer resection. The best survival rates are associated with surgical treatment, which should be chosen whenever possible.


Assuntos
Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Segunda Neoplasia Primária/patologia , Segunda Neoplasia Primária/terapia , Neoplasias Gástricas/patologia , Idoso , Terapia Combinada , Feminino , Gastrectomia/métodos , Humanos , Metástase Linfática , Masculino , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Seleção de Pacientes , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida
4.
Eur J Surg Oncol ; 34(2): 159-65, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17566691

RESUMO

AIMS: The proportion between metastatic and examined lymph nodes (N-ratio) has been proposed as an independent prognostic factor in patients with gastric cancer. In the present work we validated the reliability of N-ratio in a large, multicenter series. PATIENTS AND METHODS: We retrospectively reviewed the data of 1853 patients who underwent radical resection for gastric carcinoma. Survival of patients with >15 (Group-1, n=1421) and those with < or =15 (Group-2, n=432) lymph nodes examined was separately analyzed in order to evaluate the influence of lymph node dissection on disease staging. N-ratio categories (N-ratio 0, 0%; N-ratio 1, 1-9%; N-ratio 2, 10-25%; N-ratio 3, >25%) were determined by the best cut-off approach. RESULTS: At multivariate analysis, N-ratio (but not TNM N-category) was retained as an independent prognostic factor both in Group-1 and Group-2 (HR for N-ratio 1, N-ratio 2 and N-ratio 3=1.67, 2.96 and 6.59, and 1.56, 2.68 and 4.28, respectively). After a median follow-up of 45.5 months, the 5-year overall survival rates of TNM N0, N1 and N2 patients were significantly different in Group-1 vs Group-2. This was not the case when adopting the N-ratio classification, suggesting that a low number of excised lymph nodes can lead to patients being understaged using the N-category, but not N-ratio. Moreover, N-ratio identified subsets of patients with significantly different survival rates within TNM N1 and N2 categories in both groups. CONCLUSIONS: N-ratio is a simple and reproducible prognostic tool that can stratify patients with gastric cancer, including those cases with limited lymph node dissection. These data support the rationale to propose the implementation of N-ratio into the current TNM staging system.


Assuntos
Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Linfonodos/patologia , Estadiamento de Neoplasias/métodos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Adenocarcinoma/mortalidade , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Gastrectomia/métodos , Humanos , Imuno-Histoquímica , Excisão de Linfonodo/estatística & dados numéricos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Análise Multivariada , Valor Preditivo dos Testes , Probabilidade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Neoplasias Gástricas/mortalidade , Análise de Sobrevida
5.
Transplantation ; 71(9): 1268-76, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11397961

RESUMO

BACKGROUND: Ischemia-reperfusion injury is a major cause of early graft dysfunction after liver transplantation. Tauroursodeoxycholic acid (TUDCA), a natural amidated hydrophilic bile salt, protects from cholestasis and hepatocellular damage in a variety of experimental models, as well as from ischemia-reperfusion injury. We investigated in the human liver transplantation setting the effect of the addition of TUDCA at time of liver harvesting and cold storage on the intra- and postoperative enzyme release and liver histopathology at the end of cold storage, at reperfusion, and 7 days after transplantation. METHODS: Eighteen patients undergoing elective liver transplantation were studied, including 6 serving as controls. In six patients, TUDCA was added to the University of Wisconsin solution used during harvesting and cold storage, to reach final concentrations of 2 mM. In three of these patients, TUDCA (3 g) was infused in the portal vein of the donor before organ explantation; in the other three cases, TUDCA was given through both routes. RESULTS: The use of TUDCA did not cause adverse events. The release of aspartate aminotransferase in the inferior vena cava blood during liver flushing was significantly lower (P=0.05) in TUDCA-treated than in control grafts, as were cytolytic enzyme levels in peripheral blood during the first postoperative week (P<0.02). At electron microscopy, an overt endothelial damage (cytoplasmic vacuolization, cell leakage, and destruction with exposure of hepatocytes to the sinusoidal lumen) was invariably found in control grafts, both at reperfusion and at day 7 after transplant. These features were significantly ameliorated by TUDCA (P<0.001). Several ultrastructural cytoplasmic abnormalities of hepatocytes were seen. Among these, damage to mitochondria matrix and crystae was significantly reduced in TUDCA-treated versus control grafts (P<0.01). Mild to severe damage of bile canaliculi was a constant feature in control biopsies, with dilatation of canalicular lumen and loss of microvilli. Both these abnormalities were markedly ameliorated (P<0.001 by TUDCA). The best preservation was observed when TUDCA was given through both routes. CONCLUSIONS: The use of TUDCA during harvesting and cold storage of human liver is associated with significant protection from ischemia-reperfusion injury. The clinical significance of this findings must be studied.


Assuntos
Transplante de Fígado , Soluções para Preservação de Órgãos , Substâncias Protetoras/farmacologia , Ácido Tauroquenodesoxicólico/fisiologia , Obtenção de Tecidos e Órgãos , Adenosina , Adulto , Alopurinol , Biópsia , Temperatura Baixa , Feminino , Glutationa/efeitos dos fármacos , Hepatócitos/ultraestrutura , Humanos , Insulina , Fígado/patologia , Transplante de Fígado/fisiologia , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Preservação de Órgãos/métodos , Projetos Piloto , Cuidados Pós-Operatórios , Rafinose , Reperfusão , Ácido Tauroquenodesoxicólico/farmacologia
6.
Am J Physiol Gastrointest Liver Physiol ; 281(1): G182-90, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11408271

RESUMO

Cholangiocyte proliferation and loss through apoptosis occur in cholestatic liver diseases. Our aim was to determine the mechanisms of apoptosis in an animal model of ductal hyperplasia. Rats were fed alpha-naphthylisothiocyanate (ANIT) for 2 wk and subsequently fed normal chow for 1, 2, and 4 wk. Proliferation was assessed in sections by morphometry and in small and large cholangiocytes by proliferating cellular nuclear antigen immunoblots and measurement of cAMP levels. Apoptosis and reactive oxygen species (ROS) levels were also assessed. ANIT feeding increased small and large cholangiocyte proliferation and apoptosis. Cessation of ANIT feeding was associated with decreased proliferation and a further increase in apoptosis in small and large cholangiocytes. Cholangiocytes from ANIT-fed rats or exposed to ANIT in vitro showed increased apoptosis and ROS generation. ANIT-induced duct injury results in enhanced proliferation and apoptosis in small and large cholangiocytes. The mechanism of ANIT-induced apoptosis may be due to ROS generation induced directly by ANIT. Our model has implications for understanding the pathophysiology of cholangiopathies (characterized by the coexistence of cholangiocyte apoptosis and proliferation).


Assuntos
1-Naftilisotiocianato , Apoptose/fisiologia , Colestase Intra-Hepática/patologia , Fígado/patologia , Animais , Colestase Intra-Hepática/induzido quimicamente , Colestase Intra-Hepática/metabolismo , AMP Cíclico/metabolismo , Modelos Animais de Doenças , Fígado/química , Fígado/metabolismo , Masculino , Tamanho do Órgão , Antígeno Nuclear de Célula em Proliferação/análise , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
7.
J Hepatol ; 34(2): 284-91, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11281558

RESUMO

BACKGROUND/AIMS: We determined the role of gastrin in the regulation of cholangiocarcinoma growth. METHODS: We evaluated for the functional presence of cholecystokinin (CCK)-B/gastrin receptors in the cholangiocarcinoma cell lines, Mz-ChA-1, HuH-28 and TFK-1. We determined the effect of gastrin on the growth of Mz-ChA-1, HuH-28 and TFK-1 cells. We evaluated the effect of gastrin on growth and apoptosis of Mz-ChA-1 in the absence or presence of inhibitors for CCK-A (L-364, 718) and CCK-B/gastrin (L-365, 260) receptors, the intracellular Ca2+ chelator (BAPTA/AM), and the protein kinase C (PKC)-alpha inhibitor, H7. We evaluated if gastrin effects on Mz-ChA-1 growth and apoptosis are associated with membrane translocation of PKC-alpha. RESULTS: Gastrin inhibited DNA synthesis of Mz-ChA-1, HuH-28 and TFK-1 cells in a dose- and time-dependent fashion. The antiproliferative effect of gastrin on Mz-ChA-1 cells was inhibited by L-365, 260, H7 and BAPTA/AM but not L-364, 718. Gastrin induced membrane translocation of PKC-alpha. The inhibition of growth of Mz-ChA-1 cells by gastrin was associated with increased apoptosis through a PKC-dependent mechanism. CONCLUSIONS: Gastrin inhibits the growth of Mz-ChA-1, HuH-28 and TFK-1 cells. Gastrin inhibits growth and induces apoptosis in Mz-ChA-1 cells through the Ca2+-dependent PKC-alpha. The data suggest a therapeutic role for gastrin in the modulation of cholangiocarcinoma growth.


Assuntos
Apoptose/efeitos dos fármacos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/patologia , Gastrinas/farmacologia , Isoenzimas/metabolismo , Proteína Quinase C/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Benzodiazepinonas/farmacologia , Divisão Celular/efeitos dos fármacos , Colangiocarcinoma/metabolismo , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Compostos de Fenilureia/farmacologia , Proteína Quinase C-alfa , Receptor de Colecistocinina A , Receptor de Colecistocinina B , Receptores da Colecistocinina/antagonistas & inibidores , Receptores da Colecistocinina/metabolismo , Células Tumorais Cultivadas
8.
Gastroenterology ; 119(6): 1681-91, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11113090

RESUMO

BACKGROUND & AIMS: We investigated the expression of estrogen receptor (ER) alpha and beta subtypes in cholangiocytes of normal and bile duct-ligated (BDL) rats and evaluated the role and mechanisms of estrogens in the modulation of cholangiocyte proliferation. METHODS: ER-alpha and ER-beta were analyzed by immunohistochemistry, reverse-transcription polymerase chain reaction, and Western blotting in normal and BDL rats. The effects of the ER antagonists tamoxifen and ICI 182,780 on cholangiocyte proliferation were evaluated. RESULTS: Cholangiocytes expressed both ER-alpha and ER-beta subtypes, whereas hepatocytes expressed only ER-alpha. In association with a marked cholangiocyte proliferation and with enhanced estradiol serum levels, the immunoreactivity for ER-alpha involved a 3-fold higher percentage of cholangiocytes in 3-week BDL than in normal rats; immunoreactivity for ER-beta showed a 30-fold increase. Western blot analysis showed that during BDL, the total amount of ER-beta in cholangiocytes was markedly increased (5-fold), whereas that of ER-alpha decreased slightly (-25%). Treatment with tamoxifen or ICI 182,780 of 3-week BDL rats inhibited cholangiocyte proliferation and induced overexpression of Fas antigen and apoptosis in cholangiocytes. In vitro, 17 beta estradiol stimulated proliferation of cholangiocyte, an effect blocked to the same extent by tamoxifen or ICI 182,780. CONCLUSIONS: This study suggests that estrogens and their receptors play a role in the modulation of cholangiocyte proliferation.


Assuntos
Ductos Biliares Intra-Hepáticos/citologia , Estradiol/análogos & derivados , Estrogênios/fisiologia , Animais , Apoptose/efeitos dos fármacos , Ductos Biliares/citologia , Ductos Biliares/efeitos dos fármacos , Western Blotting , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Células Epiteliais/citologia , Estradiol/sangue , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Fulvestranto , Imuno-Histoquímica , Ligadura , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar , Valores de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tamoxifeno/farmacologia
9.
Hepatology ; 32(1): 17-25, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10869284

RESUMO

We studied the role of gastrin in regulating cholangiocyte proliferation induced by bile duct ligation (BDL). In purified cholangiocytes, we evaluated (1) for the presence of cholecystokinin-B (CCK-B)/gastrin receptors, (2) the effect of gastrin on D-myo-Inositol 1,4,5-triphosphate (IP(3)) levels, and (3) the effect of gastrin on DNA synthesis and adenosine 3', 5'-monophosphate (cAMP) levels in the absence or presence of CCK-A (L-364,718) and CCK-B/gastrin (L-365,260) receptor inhibitors, 1, 2-bis(2-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid tetrakis(acetxymethyl ester) (BAPTA/AM; an intracellular Ca(2+) chelator), and 2 protein kinase C (PKC) inhibitors, 1-(5-Isoquinolinylsulfonyl)-2-methylpiperazine (H7) and staurosporin. To evaluate if gastrin effects on cholangiocyte proliferation are mediated by the isoform PKCalpha, we evaluated (1) for the presence of PKCalpha in cholangiocytes and (2) the effect of gastrin on the PKCalpha protein expression in a triton-soluble (containing cytoplasm + membrane) and a triton-insoluble (containing cytoskeleton) fraction. To evaluate the effects of gastrin in vivo, immediately following BDL, gastrin or bovine serum albumin (BSA) was infused by minipumps for 7 days to rats and we measured cholangiocyte growth and cAMP levels. We found CCK-B/gastrin receptors on cholangiocytes. Gastrin increased IP(3) levels. Gastrin inhibited DNA synthesis and cAMP synthesis in cholangiocytes. Gastrin effects on cholangiocyte functions were blocked by L-365,260, BAPTA/AM, H7, and staurosporin but not by L-364,718. Gastrin induced translocation of PKCalpha from cholangiocyte cytoskeleton to membrane. In vivo, gastrin decreased cholangiocyte growth and cAMP synthesis compared with controls. We concluded that gastrin inhibits cholangiocyte growth in BDL rats by interacting with CCK-B/gastrin receptors through a signal transduction pathway involving IP(3), Ca(2+), and PKCalpha.


Assuntos
Ductos Biliares/citologia , Cálcio/fisiologia , Colestase Extra-Hepática/patologia , Gastrinas/farmacologia , Inositol 1,4,5-Trifosfato/fisiologia , Isoenzimas/fisiologia , Proteína Quinase C/fisiologia , Receptores da Colecistocinina/fisiologia , Animais , Ductos Biliares/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos F344 , Receptores da Colecistocinina/efeitos dos fármacos
11.
Gastroenterology ; 117(1): 191-9, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10381927

RESUMO

BACKGROUND & AIMS: To investigate the role of the cholinergic system in regulation of cholangiocyte functions, we evaluated the effects of vagotomy on cholangiocyte proliferation and secretion in rats that underwent bile duct ligation (BDL rats). METHODS: After bile duct ligation (BDL), the vagus nerve was resected; 7 days later, expression of M3 acetylcholine receptor was evaluated. Cholangiocyte proliferation was assessed by morphometry and measurement of DNA synthesis. Apoptosis was evaluated by light microscopy and annexin-V staining. Ductal secretion was evaluated by measurement of secretin-induced choleresis, secretin receptor (SR) gene expression, and cyclic adenosine 3',5'-monophosphate (cAMP) levels. RESULTS: Vagotomy decreased the expression of M3 acetylcholine receptors in cholangiocytes. DNA synthesis and ductal mass were markedly decreased, whereas cholangiocyte apoptosis was increased by vagotomy. Vagotomy decreased ductal secretion. Forskolin treatment prevented the decrease in cAMP levels induced by vagotomy, maintained cholangiocyte proliferation, and decreased cholangiocyte apoptosis caused by vagotomy in BDL rats. Cholangiocyte secretion was also maintained by forskolin. CONCLUSIONS: Vagotomy impairs cholangiocyte proliferation and enhances apoptosis, leading to decreased ductal mass in response to BDL. Secretin-induced choleresis of BDL rats was virtually eliminated by vagotomy in association with decreased cholangiocyte cAMP levels. Maintenance of cAMP levels by forskolin administration prevents the effects of vagotomy on cholangiocyte proliferation, apoptosis, and secretion.


Assuntos
Ductos Biliares/citologia , Ductos Biliares/fisiologia , Fibras Colinérgicas/fisiologia , Animais , Apoptose/fisiologia , Ductos Biliares/efeitos dos fármacos , Ductos Biliares/metabolismo , Peso Corporal/fisiologia , Divisão Celular/fisiologia , Colforsina/farmacologia , AMP Cíclico/antagonistas & inibidores , AMP Cíclico/metabolismo , Hormônios/sangue , Ligadura , Fígado/anatomia & histologia , Masculino , Tamanho do Órgão/fisiologia , Ratos , Ratos Endogâmicos F344 , Receptores Colinérgicos/metabolismo , Vagotomia
12.
Hepatology ; 29(2): 307-19, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9918904

RESUMO

The aim of this study was to develop a model of selective duct damage restricted to hormone-responsive segments corresponding to the ducts damaged in primary biliary cirrhosis (PBC). Carbon tetrachloride (CCl4) was fed by gavage to rats, and 2, 7, 14, and 28 days later, small and large cholangiocytes were isolated. Apoptosis was determined in situ by morphology and in purified cholangiocytes by assessment of nuclear fragmentation by 4, 6-diamidino-2-phenylindole (DAPI) staining. Cholangiocyte proliferation was evaluated in situ by morphometry of liver sections stained for cytokeratin-19 (CK-19) and by proliferating cellular nuclear antigen (PCNA) staining in liver sections and in purified cholangiocytes by PCNA gene expression. Ductal secretion was assessed by measurement of secretin receptor (SR) gene expression and secretin-induced cyclic adenosine 3',5'-monophosphate (cAMP) synthesis and secretin-induced choleresis. Two days after CCl4 administration, there was an increased number of small ducts, but a reduction of large ducts. Apoptosis, observed only in large ducts, was associated with decreased DNA synthesis and ductal secretion. Conversely, small cholangiocytes expressed de novo the SR gene and secretin-stimulated cAMP synthesis 2 days after CCl4 treatment. Proliferation of large cholangiocytes was delayed until 7 days, which was associated with a transient increase in ductal secretion in vivo. CCl4 effects on cholangiocytes were reversed by day 28. CCl4 treatment causes a decrease in large duct mass as a result of a higher rate of apoptosis and absence of initial proliferation in large cholangiocytes. These processes were concomitant with a decrease of ductal secretion in large cholangiocytes. Small cholangiocytes appear resistant to CCl4-induced apoptosis, and proliferate and transiently compensate for loss of proliferative and secretory activity of large cholangiocytes.


Assuntos
Ductos Biliares Intra-Hepáticos/patologia , Tetracloreto de Carbono/administração & dosagem , Cirrose Hepática Biliar/induzido quimicamente , Cirrose Hepática Biliar/patologia , Animais , Apoptose , Bicarbonatos/metabolismo , Bile/fisiologia , Ductos Biliares Intra-Hepáticos/metabolismo , Divisão Celular , Núcleo Celular/patologia , AMP Cíclico/biossíntese , DNA/biossíntese , Modelos Animais de Doenças , Células Epiteliais/patologia , Corantes Fluorescentes , Indóis , Cirrose Hepática Biliar/fisiopatologia , Masculino , Antígeno Nuclear de Célula em Proliferação/análise , Antígeno Nuclear de Célula em Proliferação/genética , Ratos , Receptores Acoplados a Proteínas G , Receptores dos Hormônios Gastrointestinais/genética , Secretina/farmacologia
13.
Gastroenterology ; 116(1): 179-86, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9869616

RESUMO

BACKGROUND & AIMS: We have shown that taurocholate (TC) and taurolithocholate (TLC) interact in vitro with normal cholangiocytes, increasing DNA synthesis, secretin receptor (SR) gene expression, and adenosine 3',5'-cyclic monophosphate (cAMP) synthesis. To further extend these in vitro studies, we tested the hypothesis that bile acids (BAs) directly stimulate cholangiocyte proliferation and secretion in vivo. METHODS: After feeding with TC or TLC (1% for 1-4 weeks), we assessed the following in vivo: (1) ductal proliferation by both morphometry and immunohistochemistry for proliferating cell nuclear antigen (PCNA) and measurement of [3H]thymidine incorporation; and (2) the effect of secretin on bile secretion and bicarbonate secretion in vivo. Genetic expression of H3-histone and SR and intracellular cAMP levels were measured in isolated cholangiocytes. RESULTS: After BA feeding, there was an increased number of PCNA-positive cholangiocytes and an increased number of ducts compared with control rats. [3H]Thymidine incorporation, absent in control cholangiocytes, was increased in cholangiocytes from BA-fed rats. In BA-fed rats, there was increased SR gene expression (approximately 2.5-fold) and secretin-induced cAMP levels (approximately 3.0-fold) in cholangiocytes, which was associated with de novo secretin-stimulated bile flow and bicarbonate secretion. CONCLUSIONS: These data indicate that elevated BA levels stimulate ductal secretion and cholangiocyte proliferation.


Assuntos
Ácidos e Sais Biliares , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Animais , Bile/metabolismo , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/farmacologia , Ductos Biliares Intra-Hepáticos/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Colagogos e Coleréticos/farmacologia , AMP Cíclico/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/patologia , Masculino , Ratos , Ratos Endogâmicos F344 , Receptores Acoplados a Proteínas G , Receptores dos Hormônios Gastrointestinais/biossíntese , Receptores dos Hormônios Gastrointestinais/genética , Secretina/metabolismo , Ácido Taurocólico/farmacologia , Ácido Taurolitocólico/farmacologia , Timidina/metabolismo
14.
Liver Transpl Surg ; 4(6): 441-7, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9791153

RESUMO

Hepatitis C virus (HCV) infection is one of the major causes leading to orthotopic liver transplantation (OLT) worldwide. Although viral infection persists in almost all patients, the pathology of recurrent HCV infection after OLT is not well characterized. To address this issue, we compared the pathological findings of 28 patients who underwent transplantation for HCV-related cirrhosis (group A, aged 47 +/- 15 years; 23 men, 5 women) with those of 21 patients who underwent transplantation for nonviral indications (group B, aged 45 +/- 21 years; 13 men, 8 women) during the first year after transplantation. Patients from group A were assessed for serum HCV RNA by 5' untranslated region nested polymerase chain reaction before and 1 year after OLT. Patients underwent protocol liver biopsies 3 months and 1 year after transplantation. Group A patients more frequently had histological evidence of hepatic steatosis than group B patients, both at 3 months (P = .003) and 1 year (P = .003) after OLT. Fibrosis and portal inflammation were statistically more frequent in group A 1 year after transplantation. The sensitivity of steatosis in detecting histological disease recurrence was 100% at 3 months and 94% at 1 year; the specificity was 40% and 60%, respectively. Conversely, steatosis was 100% specific in detecting viral recurrence, with a sensitivity of 89%. The 1-year actuarial incidence of abnormal transaminase levels was 52% in group A and 13% in group B (P = .05). No biochemical or histological differences between patients infected with genotype 1b and patients with other HCV genotypes were found. Hepatic steatosis is a specific sign of viral recurrence after liver transplantation and a less specific sign of disease recurrence. HCV-infected liver transplant recipients often develop abnormal transaminase levels and liver fibrosis 1 year after OLT; these features are unrelated to HCV genotypes.


Assuntos
Fígado Gorduroso/patologia , Hepatite C/patologia , Transplante de Fígado , Complicações Pós-Operatórias/patologia , Adulto , Feminino , Genótipo , Hepatite C/etiologia , Hepatite C/cirurgia , Anticorpos Anti-Hepatite C/sangue , Humanos , Técnicas Imunoenzimáticas , Hepatopatias/etiologia , Hepatopatias/patologia , Hepatopatias/cirurgia , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , RNA Viral/sangue , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Taxa de Sobrevida
16.
Hepatology ; 25(4): 927-33, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9096599

RESUMO

Bile acids have been proposed to exert immunological effects of potential pathogenic or therapeutic relevance, yet the experimental evidence remains preliminary. We reexamined the effects of a variety of bile salts with differing hydrophilic-hydrophobic properties on the production of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF alpha) from monocytes and Kupffer cells. Monocytes from healthy human donors and Kupffer cells from 5-week-old mice were incubated for up to 18 hours with or without varying concentrations of bile salts and lipopolysaccharide (LPS). Monocyte viability was > or = 95% with up to 250 mumol/L sodium ursodeoxycholate and < or = 90% with 200 mumol/L chenodeoxycholate, decreasing sharply at higher concentrations. Kupffer cells were more vulnerable, particularly to chenodeoxycholate (viabilities of 25% and 0% at concentrations of 100 mumol/L and 200 mumol/L, respectively). In monocytes incubated in the presence of 20% fetal calf serum, neither ursodeoxycholate and chenodeoxycholate, nor a variety of other unconjugated and conjugated bile acids, tested up to their maximal noncytotoxic concentrations, influenced the IL-6 and TNF alpha production, at any level of LPS stimulation. Similar to monocytes, incubation of murine Kupffer cells with ursodeoxycholate and chenodeoxycholate did not influence cytokine release. In contrast, the addition of 10 nmol/L dexamethasone to monocytes significantly decreased TNF-alpha and IL-6 release (69 +/- 11% and 48 +/- 15%, respectively). When monocytes were incubated with 200 mumol/L chenodeoxycholate in the presence of lower concentrations of fetal calf serum (10% and 5%, respectively) a significant inhibition of cytokine release was observed, whereas incubation with ursodeoxycholate did not cause any effect. Flow cytometry using fluoresceinated LPS showed that chenodeoxycholate does not interact with the CD14 receptor, thus excluding the possibility of an interference with the LPS uptake by monocytes. Incubation with [14C]-chenodeoxycholate showed that the intracellular bile acid uptake was inversely related to the concentration of fetal calf serum, being negligible (< 3 fmol/cell) at the highest level. In conclusion, bile acids with widely different hydrophobicities are incapable of influencing the release of IL-6 and TNF alpha by monocytes and Kupffer cells, provided they are studied at noncytotoxic concentrations and in the presence of physiological amounts of proteins.


Assuntos
Ácidos e Sais Biliares/farmacologia , Interleucina-6/biossíntese , Células de Kupffer/efeitos dos fármacos , Células de Kupffer/imunologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Animais , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/metabolismo , Ácido Quenodesoxicólico/farmacologia , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Humanos , Técnicas In Vitro , Células de Kupffer/ultraestrutura , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Microscopia Eletrônica , Monócitos/metabolismo , Ácido Ursodesoxicólico/farmacologia
17.
Scand J Clin Lab Invest ; 54(6): 459-64, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7809579

RESUMO

We investigated whether the oral administration of SAMe influences the hepatic availability of sulphur amino acids and the extent of bile salt amidation with taurine in liver cirrhosis. Ten patients with cirrhosis (eight Child-Pugh A and 2 B, aged 48-65 years), were studied before and 2 months after oral SAMe administration (800 mg per day). Bile was obtained using a string-test device (Entero-test), after gall-bladder contraction with caerulein. No significant changes were found in the per cent composition of biliary amino acids, except for an increase in glutamic acid (from 3.7 +/- 0.6% before to 6.1 +/- 1.1% after SAMe, p = 0.003) and taurine from 2.2 +/- 2.3% (range 0.4-6.8) to 7.2 +/- 9.2% (range 0.5-28.1), (NS). HPLC analysis showed a trend towards increased per cent tauroconjugation of all individual bile salts, with a significant rise in taurochenodeoxycholic acid (from 15.0 +/- 9.4% to 25.3 +/- 9.7%, p = 0.05) and a drop in glycocholic acid (from 39.1 +/- 15.3% to 25.3 +/- 9.8%, p = 0.05). These data suggest that in the cirrhotic liver exogenous SAMe is partially metabolized to taurine, which is used for bile salt amidation.


Assuntos
Ácidos e Sais Biliares/metabolismo , Cirrose Hepática/metabolismo , S-Adenosilmetionina/farmacologia , Taurina/metabolismo , Administração Oral , Idoso , Aminoácidos/sangue , Aminoácidos/metabolismo , Bile/efeitos dos fármacos , Bile/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
J Cardiovasc Surg (Torino) ; 22(2): 190-3, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7228894

RESUMO

Superior Vena Caval Thrombosis is a preventable and treatable complication of Subclavian Vein Catheterization. Radionuclide Vena Cavograms are suggested as simple and safe procedures for detection and follow-up studies.


Assuntos
Cateterismo/efeitos adversos , Trombose/etiologia , Veia Cava Superior , Adolescente , Feminino , Humanos , Cintilografia , Veia Subclávia , Tecnécio , Trombose/diagnóstico por imagem
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