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1.
Pathol Res Pract ; 247: 154546, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37224658

RESUMO

INTRODUCTION: Ciliated foregut cysts (CFCs) are frequently described in liver, pancreas and gallbladder and generally considered benign although one case of squamous cell metaplasia and five cases of squamous cell carcinoma arising from a ciliated hepatic foregut cyst have been reported. Here we explore two cancer-testis antigens (CTAs), Sperm protein antigen 17 (SPA17) and Sperm flagellar 1 (SPEF1) expression in a rare case of CFC of the common hepatic duct MATERIALS AND METHODS: 3 µm-thick CFC sections were immunohistochemically treated with antibodies raised against human SPA17 or SPEF1. In silico Protein-Protein Interaction (PPI) network and differential protein expression were also investigated RESULTS: Immunohistochemistry revealed SPA17 and SPEF1 in the cytoplasm of ciliated epithelium. SPA17, but not SPEF1, was also detected in cilia. The PPI networks demonstrated that other CTAs are significantly predicted functional partners with SPA17 and SPEF1. The differential protein expression demonstrated that SPA17 was higher in breast cancer, cholangiocarcinoma, liver hepatocellular carcinoma, uterine corpus endometrial carcinoma, gastric adenocarcinoma, cervical squamous cell carcinoma, bladder urothelial carcinoma. SPEF1 expression was higher in breast cancer, cholangiocarcinoma, uterine corpus endometrial carcinoma and kidney renal papillary cell carcinoma CONCLUSIONS: Our study suggests that further characterization of SPA17 and SPEF1 in patients with CFCs might provide significant insights to understand the mechanisms underlying their potential to malignant transformation.


Assuntos
Carcinoma de Células Renais , Carcinoma de Células Escamosas , Carcinoma de Células de Transição , Colangiocarcinoma , Cistos , Neoplasias do Endométrio , Neoplasias Renais , Hepatopatias , Neoplasias da Bexiga Urinária , Humanos , Masculino , Feminino , Testículo/metabolismo , Ducto Hepático Comum/metabolismo , Ducto Hepático Comum/patologia , Sêmen/metabolismo , Hepatopatias/patologia , Cistos/patologia , Carcinoma de Células Escamosas/patologia , Espermatozoides/metabolismo , Espermatozoides/patologia
2.
Environ Toxicol ; 36(2): 194-203, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32996673

RESUMO

Carbon tetrachloride (CCl4 ) exposure can induce hepatic ductular reactions. To date, however, the related mechanism remains largely unknown. Sonic hedgehog (Shh) and Yes-associated protein (Yap) signaling are correlated with liver injury and regeneration. Herein, we investigated the role of Shh and Yap signaling in the fate of ductular reaction cells in CCl4 -treated livers and the possible mechanisms. Wild-type and Shh-EGFP-Cre male mice were exposed to CCl4 (2 mL/kg), and then treated with or without the Shh signaling inhibitor Gant61. The level of liver injury, proliferation of ductular reaction cells, and expression levels of mRNA and protein related to the Shh and Yap signaling components were assessed. Results showed that CCl4 treatment induced liver injury and promoted activation and proliferation of ductular reaction cells. In addition, CCl4 induced the expression of Shh ligands in hepatocytes, accompanied by activation of Shh and Yap1 signaling in the liver. Furthermore, administration of Gant61 ameliorated liver regeneration, inhibited hepatic ductular reactions, and decreased Shh and Yap1 signaling activity. Thus, Shh-Yap1 signaling appears to play an integral role in the proliferation of ductular reaction cells in CCl4 -induced liver injury. This study should improve our understanding of the mechanism of CCl4 -induced liver injury and ductular reactions and provide support for future investigations on liver disease therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Proteínas Hedgehog/metabolismo , Ducto Hepático Comum/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Tetracloreto de Carbono/toxicidade , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Doença Hepática Crônica Induzida por Substâncias e Drogas/etiologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/patologia , Proteínas Hedgehog/antagonistas & inibidores , Proteínas Hedgehog/genética , Ducto Hepático Comum/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Masculino , Camundongos , Piridinas/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais , Proteínas de Sinalização YAP
3.
Bull Exp Biol Med ; 156(5): 654-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24770751

RESUMO

Studies by the immunohistochemical method with semiquantitative analysis of images showed that hyperprolactinemia stimulated CFTR protein manifestation in the bile ducts of female rats, which was clearly expressed in experimental cholestasis of pregnancy. The expression of CFTR in the renal tubules was reduced in hyperprolactinemia under conditions of normal liver function and in cholestasis of pregnancy. Significant positive correlations between CFTR, prolactin receptor, and multiple drug resistance protein 3 were detected in the bile ducts, but not in the renal tubules. Presumably, prolactin has a direct effect on CFTR expression in the bile ducts and indirect effect in the renal tubules. Changes in CFTR protein manifestation in the hepatic ductal structures and renal tubules in experimental pregnancy cholestasis could aggravate the disease.


Assuntos
Colestase Intra-Hepática/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Ducto Hepático Comum/metabolismo , Túbulos Renais/metabolismo , Complicações na Gravidez/metabolismo , Animais , Animais não Endogâmicos , Colestase Intra-Hepática/patologia , Feminino , Ducto Hepático Comum/patologia , Gravidez , Complicações na Gravidez/patologia , Ratos , Receptores da Prolactina/metabolismo
4.
Hepatology ; 59(4): 1393-405, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24254368

RESUMO

UNLABELLED: Although nonalcoholic fatty liver disease (NAFLD) is conventionally assessed histologically for lobular features of inflammation, development of portal fibrosis appears to be associated with disease progression. We investigated the composition of the portal inflammatory infiltrate and its relationship to the ductular reaction (DR), a second portal phenomenon implicated in fibrogenesis. The portal inflammatory infiltrate may contribute directly to fibrogenesis as well as influence the fate of the DR hepatic progenitor cells (HPCs), regulating the balance between liver repair and fibrosis. The presence of portal inflammation in NAFLD was strongly correlated with disease severity (fibrosis stage) and the DR. The portal infiltrate was characterized by immunostaining NAFLD liver biopsy sections (n = 33) for broad leukocyte subset markers (CD68, CD3, CD8, CD4, CD20, and neutrophil elastase) and selected inflammatory markers (matrix metalloproteinase 9 and interleukin [IL]-17). Cells expressing all markers examined were identified throughout the liver lobules and in portal tracts, although portal tracts were more densely populated (P < 0.01), and dominated by CD68(+) macrophages and CD8(+) lymphocytes, at all stages of disease. An increase in portal macrophages in NAFLD patients with steatosis alone (P < 0.01) was the earliest change detected, even before elevated expression of the proinflammatory cytokines, IL1B and TNF, in patients with early NASH (P < 0.05). Portal and periductal accumulation of all other cell types examined occurred in progressed NASH (all P < 0.05). CONCLUSION: Knowledge of the complex cellular composition of the portal inflammatory infiltrate and HPC/DR niche in NAFLD will shape future functional studies to elucidate the contribution of portal inflammation to HPC differentiation and NAFLD pathogenesis.


Assuntos
Fígado Gorduroso/metabolismo , Ducto Hepático Comum/metabolismo , Hepatopatias Alcoólicas/metabolismo , Sistema Porta/metabolismo , Adulto , Idoso , Biópsia , Estudos de Coortes , Fígado Gorduroso/patologia , Feminino , Ducto Hepático Comum/patologia , Humanos , Interleucina-17/metabolismo , Interleucina-1beta/metabolismo , Fígado/metabolismo , Fígado/patologia , Hepatopatias Alcoólicas/patologia , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Sistema Porta/patologia , Fator de Necrose Tumoral alfa/metabolismo
6.
Pol J Pathol ; 63(1): 65-70, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22535609

RESUMO

Hilar cholangiocarcinomas involving the bifurcation of the hepatic duct are called Klatskin tumors. A resected specimen of the hilar hepatic region with Klatskin tumor was analyzed. The lining epithelium of major biliary ducts was regular, while the majority of epithelial cells lining the excretory ducts of peribiliary glands (PBGs) exhibited malignant features. The connective tissue surrounding the PBGs was infiltrated by mucinous malignant epithelial cells, sometimes in a signet-ring cell form, with perineural invasion. The tumor epithelial cells showed distinct CK 7 and CA 19-9 positivity. The described cholangiocarcinoma was classified as the Bismuth-Corlette type IIIb and originated from the excretory ducts and acinar cells of PBGs.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Ducto Hepático Comum/patologia , Tumor de Klatskin/patologia , Idoso , Neoplasias dos Ductos Biliares/metabolismo , Biomarcadores Tumorais/análise , Feminino , Ducto Hepático Comum/metabolismo , Humanos , Imuno-Histoquímica , Tumor de Klatskin/metabolismo
7.
Ann Diagn Pathol ; 15(2): 140-4, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20952295

RESUMO

Biliary papillomatosis and papillary carcinoma are rare tumors of biliary tract; and because of their morphologic similarities, papillomatosis-papillary carcinoma sequel has been proposed. We report an unusual case of polypoid minimally invasive papillary carcinoma located at the junction between cystic and common bile ducts, complicated with biliary papillomatosis of gallbladder and cystic duct, showing focal areas of malignant change. Intrahepatic ducts, hepatic ducts, and distal common bile duct were spared. Both papillomatosis and papillary carcinoma showed areas of high p53 and p21 expression with high proliferative index. Patient is still alive for 4 years without evidence of disease after modified Whipple operation. Possible pathogenetic mechanisms are further discussed.


Assuntos
Ductos Biliares/patologia , Neoplasias do Sistema Biliar/patologia , Carcinoma Papilar/patologia , Vesícula Biliar/patologia , Papiloma/patologia , Ductos Biliares/metabolismo , Ductos Biliares/cirurgia , Neoplasias do Sistema Biliar/metabolismo , Neoplasias do Sistema Biliar/cirurgia , Carcinoma Papilar/metabolismo , Carcinoma Papilar/cirurgia , Transformação Celular Neoplásica , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ducto Cístico/metabolismo , Ducto Cístico/patologia , Ducto Cístico/cirurgia , Diagnóstico Diferencial , Feminino , Seguimentos , Vesícula Biliar/metabolismo , Vesícula Biliar/cirurgia , Ducto Hepático Comum/metabolismo , Ducto Hepático Comum/patologia , Ducto Hepático Comum/cirurgia , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , Pancreaticoduodenectomia , Papiloma/metabolismo , Papiloma/cirurgia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Proteína Supressora de Tumor p53/metabolismo
8.
Histopathology ; 57(4): 607-14, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20875072

RESUMO

AIMS: Ductular reactions occur in a wide variety of liver diseases. Their origin and function is still debated. Our understanding of these histological reactions is impaired by their great diversity; therefore rational classification should precede further detailed analysis. The aim was to achieve a reproducible classification of hepatic ductular reactions based on their immunophenotype. METHODS AND RESULTS: Sixty-nine liver specimens with ductular reactions were analysed by immunohistochemistry. The majority of the samples could be classified into three categories based on their immunophenotype. Type P(rimitive) reaction is characterized by CD56 immunoreactivity. Most primary biliary cirrhosis and focal nodular hyperplasia samples fall into this group; these ductules do not show any sign of differentiation. Type D(ifferentiating) ductules are positive for CD56, epithelial membrane antigen (EMA) and CD10. Cirrhotic samples and regenerating livers following fulminant hepatic failure contain such ductular reactions; this immunophenotype indicates hepatocytic differentiation. Biliary obstruction results in EMA-positive type O(bstructive) reactions; these ductules are similar to the normal interlobular bile ducts. CONCLUSION: Ductular reactions can be classified based on their immunophenotype. Our results may initiate further, similar, studies resulting in a generally accepted rational classification. We believe that such categorization is necessary for elucidating their biological and clinical significance.


Assuntos
Ducto Hepático Comum/patologia , Imuno-Histoquímica/normas , Hepatopatias/classificação , Hepatopatias/patologia , Ducto Hepático Comum/metabolismo , Humanos , Hepatopatias/metabolismo
9.
Hum Pathol ; 40(12): 1706-14, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19683330

RESUMO

Metallothionein is a group of small molecular weight cysteine-rich proteins with a broad variety of functions. Metallothionein has been shown to regulate apoptosis and proliferation. Overexpression of metallothionein frequently occurs in human tumors and is related to prognosis as well as therapy response. However, metallothionein expression and its clinical relevance in cholangiocarcinoma have not been investigated. The present study aimed to analyze metallothionein over-expression and its possible prognostic impact in intrahepatic cholangiocarcinoma and hilar extrahepatic cholangiocarcinoma (Klatskin tumors). We investigated the relationship of immunohistochemically demonstrated metallothionein expression with various clinicopathological parameters in a series of 56 intrahepatic and 56 extrahepatic cholangiocarcinoma. In noncancerous bile duct epithelia metallothionein was only occasionally weakly expressed; strong metallothionein overexpression (>50% metallothionein -positive tumor cells) was noted in 7 (12.5%) of 56 intrahepatic cholangiocarcinoma and 14 (25%) of 56 Klatskin tumors, which was associated with poor clinical outcome in univariate Kaplan-Meier testing in both intrahepatic cholangiocarcinoma (P = .002) and Klatskin tumors (P = .034). Moreover, strong metallothionein expression was identified as an independent prognostic parameter in multivariate Cox regression analysis in both intrahepatic cholangiocarcinoma (P = .005) and Klatskin tumors (P = .035). In contrast, cholangiocarcinoma with a papillary phenotype (8/112; 7.1%) exhibited a significant lack of strong metallothionein expression in all 8 of 8 cases. Strong metallothionein expression is identified as an independent poor prognostic parameter, and determination of the metallothionein expression may serve as an additional tool for the therapeutic management of patients with cholangiocarcinoma. In comparison, lack of metallothionein expression seems to be associated with cholangiocarcinoma with a papillary phenotype, which is generally recognized to have a better prognosis.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Ductos Biliares Intra-Hepáticos/metabolismo , Colangiocarcinoma/metabolismo , Ducto Hepático Comum/metabolismo , Tumor de Klatskin/metabolismo , Metalotioneína/biossíntese , Apoptose , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Biomarcadores Tumorais/análise , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Feminino , Ducto Hepático Comum/patologia , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Estimativa de Kaplan-Meier , Antígeno Ki-67/metabolismo , Tumor de Klatskin/mortalidade , Tumor de Klatskin/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Regulação para Cima
10.
Gastroenterology ; 133(5): 1579-91, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17983805

RESUMO

BACKGROUND & AIMS: Oval cells are postnatal hepatic progenitors with high proliferative potential and bipotent differentiation ability to become hepatocytes and cholangiocytes. Because Wnt/beta-catenin signaling is a known regulatory pathway for liver development and regeneration, we studied the role of Wnt signaling in oval cells using a mouse model of chronic liver injury. METHODS: A 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-enriched diet was used to stimulate oval cell proliferation. Livers were harvested for histologic analysis and determination of Wnt family gene expression by quantitative reverse transcription-polymerase chain reaction and in situ hybridization. The transgenic beta-catenin reporter mouse (TOPGAL) was use to confirm canonical Wnt/beta-catenin signal transduction in proliferating oval cells within atypical ductal proliferations (ADPs). Confocal fluorescence microscopy and immunohistochemistry was used to confirm colocalization of beta-catenin with the oval cell antigen A-6. RESULTS: Several Wnt ligands were significantly induced in the liver of DDC-fed mice and localized to proliferating cells in and adjacent to the ADPs. Oval cells isolated from DDC-fed mouse livers showed the presence of active beta-catenin in the nucleus along with cell-cycle entry in response to purified Wnt3a in vitro. Moreover, Wnt3a-induced beta-catenin/T-cell factor/lymphoid enhancer factor (TCF/LEF) transcriptional activation was quantified by TCF/LEF luciferase reporter assays. CONCLUSIONS: From these data, we conclude that oval cells respond to Wnt ligands (Wnt3a) in vitro with an increase in amino-terminus dephosphorylated beta-catenin and cell-cycle entry and that canonical Wnt/beta-catenin/TCF signaling is active in proliferating facultative hepatic progenitor cells in vivo. These findings may lend insight to the consequences of increased canonical Wnt signaling during periods of chronic liver injury.


Assuntos
Fígado/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Dicarbetoxi-Di-Hidrocolidina/farmacologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Ducto Hepático Comum/metabolismo , Ducto Hepático Comum/patologia , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/patologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Camundongos , Camundongos Transgênicos , Células-Tronco/efeitos dos fármacos , Células-Tronco/patologia , Fatores de Transcrição TCF/genética , Fatores de Transcrição TCF/metabolismo , Proteínas Wnt/genética , Proteína Wnt3 , Proteína Wnt3A , beta Catenina/genética
11.
Lipids Health Dis ; 5: 15, 2006 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-16792807

RESUMO

BACKGROUND: Tegaserod is effective in treating IBS patients with constipation, and does not alter gallbladder motility in healthy individuals or in patients with IBS. However, it is not known if tegaserod affects the biliary tract in gallstone disease, so to this end the effects of tegaserod on bile composition and hepatic secretion of Richardson ground squirrels maintained on an enriched cholesterol diet were examined. RESULTS: Animals were fed either a control (0.03%) or enriched (1%) cholesterol diet for 28 days, and treated s.c. with tegaserod (0.1 mg/kg BID) or vehicle. Bile flow, bile acid, phospholipids and cholesterol secretion were measured with standard methods. Tegaserod treatment or enriched cholesterol diet, alone or combination, did not alter body or liver weights. The enriched cholesterol diet increased cholesterol saturation index (CSI), cholesterol concentrations in gallbladder and hepatic duct bile by approximately 50% and decreased bile acids in gallbladder bile by 17%. Tegaserod treatment reversed these cholesterol-induced changes. None of the treatments, drug or diet, altered fasting gallbladder volume, bile flow and bile salts or phospholipid secretion in normal diet and cholesterol-fed animals. However, tegaserod treatment prevented the decreases in bile acid pool size and cycling frequency caused by the enriched cholesterol diet, consequent to re-establishing normal bile acid to concentrations in the gall bladder. Tegaserod had no effect on these parameters with normal diet animals. CONCLUSION: Tegaserod treatment results in increased enterohepatic cycling and lowers cholesterol saturation in the bile of cholesterol-fed animals. These effects would decrease conditions favorable to cholesterol gallstone formation.


Assuntos
Bile/química , Colesterol na Dieta/administração & dosagem , Vesícula Biliar/efeitos dos fármacos , Indóis/farmacologia , Sciuridae/metabolismo , Animais , Bile/metabolismo , Ácidos e Sais Biliares/metabolismo , Peso Corporal/efeitos dos fármacos , Colesterol/metabolismo , Vesícula Biliar/metabolismo , Fármacos Gastrointestinais/administração & dosagem , Fármacos Gastrointestinais/farmacologia , Ducto Hepático Comum/efeitos dos fármacos , Ducto Hepático Comum/metabolismo , Indóis/administração & dosagem , Injeções Subcutâneas , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/química , Fígado/efeitos dos fármacos , Fígado/crescimento & desenvolvimento , Fígado/metabolismo , Masculino , Tamanho do Órgão/efeitos dos fármacos , Fosfolipídeos/metabolismo , Distribuição Aleatória , Sciuridae/crescimento & desenvolvimento
12.
Eur Radiol ; 15(10): 2122-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15999215

RESUMO

The aim of our study was to prepare in vitro a pineapple juice (PJ) solution labeled with a minimal gadolinium concentration working as a negative contrast agent in heavily T2-weighted imaging and to assess that solution in vivo as a negative oral contrast agent for magnetic resonance cholangiopancreatography (MRCP). Three PJs were compared in vitro according to their T2. Increasing concentrations of gadolinium (Gd)-DOTA in PJ were assessed in vitro for T2 reduction. Single-shot turbo spin echo T2-weighted MR cholangiopancreatograms were obtained for 35 patients with suspected biliopancreatic duct disease, before and after ingestion of the PJ/Gd-DOTA solution. Signal intensity (SI) measurements of gastroduodenal lumens, pancreatobiliary ducts, and image quality scores were obtained systematically before and after contrast ingestion. The in vitro selected Gd-DOTA concentration in the PJ was 2.76 mmol/l. Ingestion of 180 ml of PJ labeled with 1 ml of Gd-DOTA eliminated efficiently the gastroduodenal SI in MRCP, improving significantly the rates of complete visualization of the pancreatobiliary ducts (P<0.01) and the MRCP image quality scores (P<0.05). All patients easily ingested the contrast solution and found the solution palatable. PJ labeled with gadolinium constituted an efficient and convenient negative oral contrast agent for MRCP.


Assuntos
Ananas , Bebidas , Colangiopancreatografia por Ressonância Magnética/métodos , Meios de Contraste/administração & dosagem , Compostos Heterocíclicos/administração & dosagem , Compostos Organometálicos/administração & dosagem , Administração Oral , Ducto Colédoco/diagnóstico por imagem , Ducto Colédoco/metabolismo , Meios de Contraste/metabolismo , Duodeno/diagnóstico por imagem , Duodeno/metabolismo , Feminino , Mucosa Gástrica/metabolismo , Ducto Hepático Comum/diagnóstico por imagem , Ducto Hepático Comum/metabolismo , Compostos Heterocíclicos/metabolismo , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Relaxamento Muscular/efeitos dos fármacos , Compostos Organometálicos/metabolismo , Ductos Pancreáticos/diagnóstico por imagem , Ductos Pancreáticos/metabolismo , Preparações de Plantas , Intensificação de Imagem Radiográfica , Reprodutibilidade dos Testes , Estômago/diagnóstico por imagem
13.
Am J Pathol ; 164(4): 1347-59, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15039222

RESUMO

Hepatic regeneration from toxic or surgical injury to the adult mammalian liver, endorses different cellular responses within the hepatic lineage. The molecular mechanisms determining commitment of a cell population at a specific lineage level to participate in liver repair as well as the fate of its progeny in the hostile environment created by the injury are not well defined. Based on the role of the Notch/Delta/Jagged system in cell fate specification and recent reports linking Notch signaling with normal bile duct formation in mouse and human liver, we examined the expression of Notch1, Notch2, Notch3, Delta1, Delta3, Jagged1, and Jagged2, and delta-like protein/preadipocyte factor 1/fetal antigen 1 (dlk) in four well-defined experimental rat models of liver injury and regeneration. Although Delta3 and Jagged2 were undetectable by reverse transcriptase-polymerase chain reaction and Northern blot, we observed the most significant up-regulation of all other transcripts in the 2-acetylaminofluorene-70% hepatectomy (AAF/PHx) model, in which liver mass is restored by proliferation and differentiation of transit-amplifying ductular (oval) cells. The most profound change was observed for dlk. Accordingly, immunohistochemical analyses in the AAF/PHx model showed a specific expression of dlk in atypical ductular structures composed of oval cells. Delta-like protein was not observed in proliferating hepatocytes or bile duct cells after partial hepatectomy or ligation of the common bile duct whereas clusters of dlk immunoreactive oval cells were found in both the retrorsine and the AAF/PHx models. Finally, we used dlk to isolate alpha-fetoprotein-positive cells from fetal and adult regenerating rat liver by a novel antibody panning technique.


Assuntos
Ducto Hepático Comum/citologia , Regeneração Hepática/fisiologia , Fígado/metabolismo , Proteínas de Membrana/biossíntese , Proteínas , Células-Tronco/metabolismo , Fatores de Transcrição , Animais , Northern Blotting , Proteínas de Ligação ao Cálcio , Proteínas de Transporte/biossíntese , Glicoproteínas/biossíntese , Ducto Hepático Comum/metabolismo , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos e Proteínas de Sinalização Intracelular , Proteína Jagged-1 , Proteína Jagged-2 , Fígado/citologia , Fígado/lesões , Masculino , Biossíntese de Proteínas , Proteínas Proto-Oncogênicas/biossíntese , Ratos , Ratos Wistar , Receptor Notch1 , Receptor Notch2 , Receptores de Superfície Celular/biossíntese , Proteínas Repressoras/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Serrate-Jagged , Células-Tronco/citologia , Regulação para Cima
14.
Mod Pathol ; 10(4): 348-53, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9110297

RESUMO

Liver regeneration after massive hepatic necrosis is characterized by the presence and formation of ductular hepatocytes (DHs). Several studies suggested that these structures might serve as bipotential progenitor cells, as demonstrated by phenotypic features characteristic of both hepatocytes and biliary epithelial cells. In this investigation, 33 liver allograft explants after primary graft failure 1 to 14 days after orthotopic liver transplantation were examined to study the formation and differentiation of DHs. As demonstrated by earlier studies, antibody to CK-19 defines the biliary epithelial cell lineage, whereas HepPar 1 is hepatocyte specific. Antibodies to CK-19, vimentin and alpha-fetoprotein, HepPar 1, and AE-1 were used for immunoperoxidase staining of 33 failed liver allograft specimens with regeneration. DHs were seen along the limiting plates at Day 1, but reactivity to HepPar 1 started only at Day 4 post injury. Vimentin and alpha-fetoprotein were not detectable in the DHs. The DHs reacted with AE-1 and anti-CK-19 starting at Day 1, but reactivity to HepPar 1 started only at Day 4 post injury. DHs are formed along the limiting plates and acquire phenotypic characteristics of bile duct epithelium as early as Day 1 after liver injury and of hepatocytes only at Day 4 after liver injury. We conclude that DHs might represent bipotential progenitor cells in regenerating liver.


Assuntos
Ducto Hepático Comum/patologia , Regeneração Hepática , Transplante de Fígado/patologia , Biomarcadores/análise , Sobrevivência de Enxerto , Ducto Hepático Comum/metabolismo , Humanos , Técnicas Imunoenzimáticas , Imunofenotipagem , Queratinas/análise , Necrose
15.
Dig Dis Sci ; 42(3): 489-91, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9073128

RESUMO

The gallbladder is traditionally regarded as an absorptive organ. There is increasing evidence that the gallbladder mucosa can have a secretory function. We studied a patient with primary sclerosing cholangitis whose gallbladder was excluded from his extrahepatic bile ducts by stricture formation. He was admitted into hospital because of cholecystitis and cholangitis and required separate drainage tubes into his gallbladder and common hepatic duct. This unique combination of drains afforded the opportunity to examine hepatic bile and gallbladder secretion. We analyzed samples for fluid volume, protein, electrolyte concentrations and biliary lipids. The simultaneous, yet separate, drainage from the gallbladder and the liver had a striking difference. The former was colorless to opalescent; the latter always golden brown. Hepatic bile flow was continuous but gallbladder drainage was variable in volume, intermittent, and occurred only after a meal. The gallbladder fluid had no bilirubin, bile salts, cholesterol, or phospholipids and had the ionic profile of an extracellular fluid. It was alkaline and contained abundant bicarbonate. We have shown that the gallbladder can secrete. In addition, these observations may also have important implications in the pathogenesis and prevention of gallbladder sludge and stones.


Assuntos
Vesícula Biliar/metabolismo , Idoso , Bile/química , Bile/metabolismo , Líquidos Corporais/química , Líquidos Corporais/metabolismo , Colangite Esclerosante/diagnóstico , Colangite Esclerosante/fisiopatologia , Colangite Esclerosante/cirurgia , Colecistite/diagnóstico , Colecistite/fisiopatologia , Colecistite/cirurgia , Colecistografia , Colecistostomia , Drenagem/métodos , Vesícula Biliar/cirurgia , Ducto Hepático Comum/metabolismo , Ducto Hepático Comum/cirurgia , Humanos , Masculino , Período Pós-Prandial
16.
Anat Rec ; 244(3): 327-43, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8742698

RESUMO

BACKGROUND: A subtraction screen isolated CRP-ductin (CRP), a gene expressed in intestinal crypts. METHODS: DNA sequencing, in situ hybridization, immunostaining, Western and Northern blotting were used to characterize murine CRP. RESULTS: CRP is restricted to the intestine and its associated glands. In the small intestine, CRP mRNA is expressed in crypt cells at all stages of differentiation from the stem cells to the terminally differentiating cells of the crypt top, but not in the mature cells of the villus. In the colon, CRP mRNA is most heavily expressed in the mid-crypt. Expression is also seen in the pancreas and pancreatic ducts, and in the epithelium lining larger hepatic ducts, but not in the liver parenchyma or stomach. CRP protein is localized to the lumenal aspect of crypt cells in the small intestine. In the colon, the protein is seen in the lumenal aspect of surface epithelial cells. CRP protein is similarly found in the lumenal aspect of epithelial cells lining the pancreatic duct system and the larger hepatic ducts. Two cDNA variants, CRP-alpha and CRP-beta, were cloned from mouse jejunal epithelium. Their 3'-sequence differs in an 82-bp domain unique to CRP-beta. CONCLUSIONS: The CRP-alpha sequence predicts a protein with a short cytoplasmic region, a transmembrane domain, and a large extracellular region composed of many repeats (8 scavenger receptor domains, 5 CUB-domains, 1 ZP-domain, and 6 copies of a previously unreported domain which we call the CRP-domain). The structure of the CRP protein suggests a role in ligand interaction; possible functions are discussed.


Assuntos
Proteína Receptora de AMP Cíclico/biossíntese , Mucosa Intestinal/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte , Proteína Receptora de AMP Cíclico/química , Proteína Receptora de AMP Cíclico/genética , Regulação da Expressão Gênica , Ducto Hepático Comum/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Ductos Pancreáticos/metabolismo , Análise de Sequência de DNA
17.
West Indian med. j ; 44(4): 146-7, Dec. 1995.
Artigo em Inglês | MedCarib | ID: med-4789

RESUMO

A case of obstructive jaundice secondary to a neurofibroma in the common hepatic duct is presented. The histological appearance was that of a plexiform neurofibroma. The clinicopathological features are discussed (AU)


Assuntos
Adulto , Relatos de Casos , Feminino , Humanos , Neurofibroma Plexiforme/patologia , Colestase/etiologia , Neoplasias dos Ductos Biliares/patologia , Neurofibroma Plexiforme/cirurgia , Ducto Hepático Comum/metabolismo
18.
Pharmacol Ther ; 64(1): 77-97, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7846117

RESUMO

Bile is an important excretory route for the elimination of amphiphilic organic anions, and hepatocytes are the primary secretory units of bile formation. The hepatocytic basolateral and canalicular membranes are equipped with various carrier proteins. Transport across the canalicular membrane represents a major concentrative step. Various ATP-dependent transporters have been identified, such as a multispecific organic anion transporter (canalicular multispecific organic ion transporter, cMOAT), a bile acid transporter and several P-glycoproteins. TR- rats, which lack cMOAT activity, have been valuable in defining the substrate specificity of cMOAT. A wide range of glucuronide-, glutathione- and sulfate-conjugates are transported by this system.


Assuntos
Proteínas de Transporte/fisiologia , Fígado/metabolismo , Xenobióticos/farmacocinética , Animais , Proteínas de Transporte de Ânions , Membrana Basal/metabolismo , Transporte Biológico , Glucuronatos/metabolismo , Glutationa/metabolismo , Ducto Hepático Comum/metabolismo , Humanos , Metais/farmacocinética , Ésteres do Ácido Sulfúrico/metabolismo
19.
Hepatology ; 5(1): 21-7, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3967862

RESUMO

Female Hartley guinea pigs fed a 0.5% cholesterol-supplemented diet were found to form pigmented gallstones after 6 weeks (17/23) and 12 weeks (11/11), while only 2 of 44 animals fed a trace cholesterol diet formed gallstones over a comparable period. The light brown stones consisted primarily of aggregates of fine granular crystals, morphologically similar to calcium bilirubinate crystals. The stones were soluble in 0.1 N sodium hydroxide and were found to contain a substance which co-migrated with unconjugated bilirubin during thin-layer chromatography. Despite hypercholesterolemia (202 +/- 34 vs. 59 +/- 22 mg per dl in controls, p less than 0.05) and fatty infiltration of the liver, cholesterol-fed animals had a lithogenic index of only 0.22 +/- 0.04 in gallbladder bile as compared to a lithogenic index of 0.02 +/- 0.01 in animals fed the trace cholesterol diet. Accordingly, no cholesterol monohydrate crystals were found in any animals. Hematocrits among cholesterol-fed animals (47.6 +/- 1.2%) were lower than those of controls (54.8 +/- 1.3%, p less than 0.05) probably as a result of the cholesterol-induced hemolytic anemia which has been reported by others in this species. Fasting gallbladder volume was greater in cholesterol-fed animals (2.4 +/- 0.18 ml) than in controls (1.7 +/- 0.11, p less than 0.0025), and a comparable increase in gallbladder dry tissue mass was found. There was no evidence of biliary obstruction, however, and the gallbladder contractile response to octapeptide cholecystokinin was comparable in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Colelitíase/etiologia , Absorção , Animais , Bile/análise , Bile/metabolismo , Colelitíase/metabolismo , Colesterol na Dieta/administração & dosagem , Feminino , Vesícula Biliar/metabolismo , Vesícula Biliar/fisiologia , Cobaias , Ducto Hepático Comum/metabolismo
20.
Am J Physiol ; 242(5): G522-32, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-7081444

RESUMO

The biliary excretion of [3H]-25-hydroxyvitamin D3 ([3H]25(OH)D3) was studied in vitamin D-depleted female rats over a 3-h period after intravenous or intraduodenal administration of intact [3H]25(OH)D3 and after the intraduodenal readministration of the [3H]25(OH)D3-derived biliary material. In each group four doses of 25(OH)D3 were administered (0.25, 2.5, 25, and 250 nmol/100 g). Over the dose range studied, the biliary excretion of [3H]25(OH)D3 could not be saturated, indicating that the biliary excretion of 25(OH)D3 is a reliable detoxification mechanism in circumstances of 25(OH)D3 intoxication. Analysis of plasma, liver, and bile suggests that the canalicular membrane seems to be rate limiting in the biliary excretion of 25(OH)D3. The intraduodenal administration of biliary excretion compounds derived from [3H]25(OH)D3 showed that they are efficiently reexcreted in newly secreted bile, confirming the existence of an enterohepatic circulation for 25(OH)D3. In this group of animals, however, the plasma analysis indicates that these compounds reach the systemic circulation in insignificant quantities, suggesting that the enterohepatic circulation probably plays a limited role in the body 25(OH)D3 economy.


Assuntos
Ducto Hepático Comum/metabolismo , Hidroxicolecalciferóis/metabolismo , Deficiência de Vitamina D/metabolismo , Animais , Calcifediol , Relação Dose-Resposta a Droga , Circulação Êntero-Hepática , Feminino , Hidroxicolecalciferóis/administração & dosagem , Hidroxicolecalciferóis/uso terapêutico , Ratos , Ratos Endogâmicos , Trítio , Deficiência de Vitamina D/tratamento farmacológico
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