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1.
Biochem Biophys Res Commun ; 428(4): 494-9, 2012 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-23122814

RESUMEN

Interferon regulatory factor-3 (IRF-3), a key transcriptional factor in the type I interferon system, is frequently impaired by hepatitis C virus (HCV), in order to establish persistent infection. However, the exact mechanism by which the virus establishes persistent infection has not been fully understood yet. The present study aimed to investigate the effects of various HCV proteins on IRF-3 activation, and elucidate the underlying mechanisms. To achieve this, full-length HCV and HCV subgenomic constructs corresponding to structural and each of the nonstructural proteins were transiently transfected into HepG2 cells. IFN-ß induction, plaque formation, and IRF-3 dimerization were elicited by Newcastle disease virus (NDV) infection. The expressions of IRF-3 homodimer and its monomer, Ser386-phosphorylated IRF-3, and HCV core protein were detected by immunofluorescence and western blotting. IFN-ß mRNA expression was quantified by real-time PCR (RT-PCR), and IRF-3 activity was measured by the levels of IRF-3 dimerization and phosphorylation, induced by NDV infection or polyriboinosinic:polyribocytidylic acid [poly(I:C)]. Switching of the expression of the complete HCV genome as well as the core proteins, E1, E2, and NS2, suppressed IFN-ß mRNA levels and IRF-3 dimerization, induced by NDV infection. Our study revealed a crucial region of the HCV core protein, basic amino acid region 1 (BR1), to inhibit IRF-3 dimerization as well as its phosphorylation induced by NDV infection and poly (I:C), thus interfering with IRF-3 activation. Therefore, our study suggests that rescue of the IRF-3 pathway impairment may be an effective treatment for HCV infection.


Asunto(s)
Hepacivirus/metabolismo , Hepatitis C/inmunología , Hepatitis C/virología , Factor 3 Regulador del Interferón/antagonistas & inhibidores , Proteínas del Núcleo Viral/metabolismo , Transporte Activo de Núcleo Celular , Aminoácidos Básicos , Núcleo Celular/metabolismo , Genoma Viral , Células Hep G2 , Hepacivirus/genética , Humanos , Factor 3 Regulador del Interferón/metabolismo , Interferón beta/inmunología , Multimerización de Proteína , Proteínas del Núcleo Viral/química , Proteínas del Núcleo Viral/genética , Proteínas no Estructurales Virales/metabolismo
2.
Hepatol Res ; 38 Suppl 1: S46-51, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19125952

RESUMEN

BACKGROUND: Fulminant hepatitis is an intractable disease caused by various etiological agents. Artificial liver support (ALS) is a symptomatic treatment used to control serious symptoms, such as bleeding tendency, hepatic coma, and brain edema. METHODS: The present study involved four patients with fulminant hepatitis who were admitted to Showa University Fujigaoka Hospital between January 2007 and June 2007. All four patients were subacute type disease of indeterminate etiology. The four patients were placed on an ALS system that comprised plasma exchange and online hemodiafiltration. The effect of the ALS on various symptoms of fulminant hepatitis was evaluated, and the levels of glutamine in the patients' plasma samples and the discarded buffer were assayed using automatic analyser. RESULTS: Three of the four patients regained full consciousness and survived. The remaining patient died despite recovering from hepatic coma with ALS. The plasma glutamine levels were significantly reduced by artificial liver support. The estimated distribution volume of removed Gln ranged from 30 L to 60 L. CONCLUSIONS: Plasma exchange in combination with online hemodiafiltration is a promising and effective method for purifying the blood of patients with fulminant hepatitis.

3.
Can J Gastroenterol ; 22(8): 681-5, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18701945

RESUMEN

INTRODUCTION: Although endoscopic transpapillary gallbladder drainage (ETGBD) has been reported to be an effective treatment for acute cholecystitis, technical difficulties have precluded more widespread use of this technique. Case evaluations that can predict the occurrence of such difficulties should increase the acceptance of ETGBD for acute cholecystitis treatment. OBJECTIVE: To establish a pretreatment evaluation protocol for patients with acute cholecystitis. METHODS: Eleven patients with acute cholecystitis who received ETGBD in 2003 or 2004 were enrolled in the present retrospective study. The frequency of success, complications and overall effectiveness of ETGBD for treatment of cholecystitis were measured. Factors that could affect ETGBD success, including clinical and laboratory parameters, and gallbladder ultrasonograms, were also evaluated. RESULTS: ETGBD was successful in seven of 11 patients (success rate 63.6%). All seven patients who underwent ETGBD successfully were afebrile and asymptomatic within a few days. No clinical or laboratory variables were significantly associated with the success of ETGBD. In contrast, ultrasonographic measures of gallbladder minor-axis length and wall thickness in successful cases were significantly shorter (27.4 mm versus 38.0 mm; P=0.008) and thinner (4.2 mm versus 9.0 mm; P=0.041) relative to unsuccessful cases. CONCLUSIONS: Ultrasonographic measures of gallbladder minor-axis length and wall thickness can serve as important predictors of ETGBD technical difficulties during pretreatment evaluation of patients with acute cholecystitis.


Asunto(s)
Colecistitis Aguda/cirugía , Drenaje/métodos , Endoscopía del Sistema Digestivo , Anciano , Anciano de 80 o más Años , Colecistitis Aguda/diagnóstico por imagen , Femenino , Vesícula Biliar/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Ultrasonografía
4.
J Gastroenterol ; 41(4): 383-7, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16741619

RESUMEN

A 49 year-old man was referred to our hospital for fear of developing fulminant hepatic failure. There had been an outbreak of fulminant hepatitis B in a dialysis clinic in the western part of Honshu, Japan, that resulted in four deaths among six patients. After the sixth patient contracted severe hepatitis, all patients in the unit were screened biweekly for hepatitis B surface antigen (HBsAg) to detect newly infected patients as soon as possible. Our patient was the seventh victim, and on the day he gave a positive result for HBsAg, his hepatitis B virus (HBV) DNA level had reached 1.1 x 10(11) copies/ml as assessed by real time polymerase chain reaction. Sequence analysis of the causal HBV revealed the presence of a mutation in the precore region (nt 1896), two mutations in the core promoter (nt 1762 and nt 1764), and some minor mutations in the P gene that were restricted to the upstream region. These mutations are indicative of a virus with a high replicative rate that cannot secrete HBeAg. Taken together, these findings indicate that it is very likely that the replicative ability of the causal virus was as vigorous as that of HBV in hepatitis B e antigen-positive asymptomatic carriers with markedly high viral titers. The present case report provides clinical evidence of a possible association between the rapid spread of highly replicative HBV before host immunological recognition and the development of fulminant hepatitis.


Asunto(s)
Virus de la Hepatitis B/fisiología , Hepatitis B/virología , Fallo Hepático Agudo/etiología , Replicación Viral , ADN Viral/análisis , ADN Viral/genética , Estudios de Seguimiento , Hepatitis B/complicaciones , Antígenos de Superficie de la Hepatitis B/análisis , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Humanos , Fallo Hepático Agudo/virología , Masculino , Persona de Mediana Edad , Mutación , Factores de Riesgo , Índice de Severidad de la Enfermedad
5.
J Gastroenterol ; 41(3): 193-7, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16699852

RESUMEN

BACKGROUND: Acute necrotizing esophagitis (ANE) is a rarely described entity that is thought to be a cause of upper gastrointestinal (UGI) bleeding, The present study examined the incidence of ANE among patients with UGI bleeding, as well as the clinical features of ANE, and the coexisting illnesses and medication histories of ANE patients. METHODS: A retrospective analysis of clinical and endoscopic findings and the clinical course in 16 patients with ANE was carried out over a 3-year period. RESULTS: We observed 16 patients (6%) of ANE in 239 patients with UGI bleeding during the 3-year period. The average age of the patients was 62.5 years. The lesions predominantly affected the lower third of the esophagus, and hiatal hernia was the most common (63%) coexisting endoscopic finding. All patients had coexisting disease. Fifty percent of patients with ANE (eight patients) had taken nonsteroidal anti-inflammatory drugs (NSAIDs). ANE also occurred in four patients with diabetic ketoacidosis. Supportive therapy, including parenteral nutrition and administration of a proton pump inhibitor, was effective. CONCLUSIONS: ANE is more common than has been previously reported, and it should be included in the differential diagnosis of UGI bleeding. ANE could be characterized as an "acute esophageal mucosal lesion," particularly in aged patients with hiatal hernia and among those who consume NSAIDs.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Esofagitis/tratamiento farmacológico , Esofagitis/patología , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Endoscopía Gastrointestinal , Esofagitis/complicaciones , Esofagitis/epidemiología , Femenino , Mucosa Gástrica/patología , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/patología , Humanos , Incidencia , Mucosa Intestinal/patología , Japón/epidemiología , Masculino , Persona de Mediana Edad , Necrosis , Estudios Retrospectivos , Resultado del Tratamiento
6.
J Gastroenterol ; 40(7): 690-7, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16082585

RESUMEN

BACKGROUND: Duodenogastric reflux after surgery increases the risk of gastric carcinoma. To determine whether bile reflux influences the development of gastric cancer in patients who have not had surgery, we compared cyclooxygenase-2 (COX-2) immunoreactivity in early gastric cancer originating from the gastric pylorus and that originating from other locations. We also examined the effects of bile acids on the expression and activity of COX-2 in gastric cells in vitro. METHODS: Tumor sections from 79 patients who underwent endoscopic mucosal resection for early intestinal-type gastric carcinoma were stained using a COX-2-specific monoclonal antibody. Immunoblotting of COX-2 was used to assess the effects of bile acids on COX-2 expression and activity in human gastric cell lines. RESULTS: Among the 79 early gastric cancer lesions studied, 13 (16%) arose in the gastric pylorus. In this group, COX-2 immunoreactivity was negative to weak in 38% (5 of 13 lesions) and moderate to strong in 62% (8 of 13 lesions). In the control group, COX-2 immunoreactivity was negative to weak in 70% (46 of 66 lesions) and moderate to strong in 30% (20 of 66 lesions). COX-2 expression was significantly elevated in early gastric cancer located in the gastric pylorus, compared with that in the other locations. In human gastric cell lines, bile acids induced COX-2 expression, mediated by the ERK 1/2 mitogen-activated protein kinase pathway. CONCLUSIONS: COX-2 expression is elevated in early gastric cancer of the gastric pylorus, a common site of gastric cancer. Bile acids induced COX-2 expression in human gastric cell lines, suggesting a role of bile reflux in gastric carcinogenesis.


Asunto(s)
Adenocarcinoma/patología , Prostaglandina-Endoperóxido Sintasas/metabolismo , Píloro/patología , Neoplasias Gástricas/patología , Adenocarcinoma/genética , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Biopsia con Aguja , Western Blotting , Ciclooxigenasa 2 , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Masculino , Proteínas de la Membrana , Persona de Mediana Edad , Estadificación de Neoplasias , Probabilidad , Pronóstico , Prostaglandina-Endoperóxido Sintasas/genética , Estudios Retrospectivos , Muestreo , Sensibilidad y Especificidad , Estadísticas no Paramétricas , Neoplasias Gástricas/genética , Células Tumorales Cultivadas
7.
J Gastroenterol ; 39(2): 181-7, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15069627

RESUMEN

A 56-year-old woman who had undergone excision of the gallbladder because of a choledochal cyst had a tumorous lesion of the pancreas identified by upper abdominal ultrasonography, but an operation was not carried out, because there was no apparent increase in the cystic mass and no elevation of serum tumor markers. In October 2001, she was admitted to our hospital to check for malignancy because of elevated levels of the tumor marker Dupan-2. Abdominal enhanced computed tomography and upper abdominal ultrasonography revealed a large multilocular cystic mass in the body to tail of the pancreas. Endoscopic retrograde cholangiopancreatography showed elongation of the common duct that communicates with the common bile duct and the main pancreatic duct, indicating an anomalous arrangement of the biliary and pancreatic duct system. No apparent communications between the cystic mass and the main pancreatic duct were observed. In January 2002, the patient underwent a spleen-preserving distal pancreatectomy, and histopathological and immunohistochemical examinations led to the diagnosis of pancreatic mucinous cystadenoma with ovarian-like stroma. The mucinous cystadenoma was detected 17 years after the operation for the choledochal cyst. To the best of our knowledge, no documented case reports of mucinous cystadenoma of the pancreas associated with a choledocal cyst have been reported to date. We present here the first case report of pancreatic mucinous cystadenoma occurring in the body to tail of the pancreas, associated with a choledocal cyst.


Asunto(s)
Colecistectomía , Quiste del Colédoco , Cistoadenoma Mucinoso/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Colangiopancreatografia Retrógrada Endoscópica , Quiste del Colédoco/complicaciones , Quiste del Colédoco/cirugía , Cistoadenoma Mucinoso/patología , Femenino , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Persona de Mediana Edad , Neoplasias Pancreáticas/patología , Tomografía Computarizada por Rayos X
8.
J Gastroenterol ; 38(6): 567-72, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12825133

RESUMEN

BACKGROUND: Only 15% to 20% of patients with chronic hepatitis C have a sustained virological response to interferon monotherapy. The aim of the present study was to compare the efficacy and safety of interferon, in combination with oral cyclosporin A, with interferon monotherapy in the treatment of chronic hepatitis C. METHODS: We assigned 120 patients with chronic hepatitis C to receive the standard Japanese dose of interferon alpha2b alone for 24 weeks or that dose of interferon alpha2b in combination with cyclosporin A, at doses of 200 mg daily for the first 4 weeks and 100 mg daily for the following 20 weeks. All patients were assessed for drug safety, tolerance, and efficacy at the end of weeks 4, 12, 24, and 48. Efficacy was assessed by the disappearance of serum hepatitis C virus (HCV)-RNA by polymerase chain reaction and normalization of serum aminotransferase. The primary endpoint was a sustained virological response; i.e., sustained undetectable serum HCV RNA at 48 weeks. RESULTS: The sustained virological response rate was significantly higher in the combination therapy group (42/76) than in the monotherapy group (14/44; P = 0.01). The sustained biochemical response rate was also higher in the combination therapy group (46/76) than in the monotherapy group (17/44; P = 0.017). In patients with genotype 1 and high viral loads, the sustained virological response rate was markedly higher in the combination therapy group (16/38) than in the monotherapy group (1/21; P = 0.006). Side-effect profiles were similar in the two groups. CONCLUSIONS: In patients with chronic hepatitis C; combined interferon and cyclosporin A treatment was more effective than interferon monotherapy. The benefit was mostly achieved in patients with a high viral load and HCV genotype 1.


Asunto(s)
Antivirales/uso terapéutico , Ciclosporina/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Interferón-alfa/uso terapéutico , Alanina Transaminasa/sangre , Antivirales/administración & dosificación , Ciclosporina/administración & dosificación , Esquema de Medicación , Quimioterapia Combinada , Femenino , Hepacivirus/genética , Humanos , Inmunosupresores/administración & dosificación , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , ARN Viral/sangre , Proteínas Recombinantes , Seguridad , Factores de Tiempo , Carga Viral
9.
J Gastroenterol ; 37(11): 916-21, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12501858

RESUMEN

BACKGROUND: We have attempted to predict the development of fulminant hepatic failure at the stage of severe acute hepatitis before the onset of coma. This prediction is valuable because it may be used to block the development of fulminant hepatic failure with appropriate medical treatment. METHODS: To establish a discrimination formula, we retrospectively compared 13 clinical and laboratory variables in 36 patients with acute viral hepatitis and prothrombin levels of 40% or less of the control value who later developed fulminant hepatic failure with these variables in 12 patients who recovered spontaneously. A prospective study of 58 patients who developed fulminant hepatic failure and 18 who spontaneously recovered confirmed the validity of this formula. RESULTS: In the retrospective study,we established the following discrimination equation: Z = -0.89 + 1.74 x (causal viruses, 1 point for type A or type B in acute hepatitis B virus [HBV] infection, 2 points for others) + 0.056 x (total bilirubin, mg/dl)-0.014 x (cholinesterase, U/ml). A positive Z value indicates that fulminant hepatic failure will develop. In the prospective study, the specificity, sensitivity, predictive accuracy, and positive and negative predictive values were 0.833, 0.983, 0.947, 0.950, and 0.938, respectively. CONCLUSIONS: The present study indicated that fulminant hepatic failure can be predicted, by a simple discrimination equation, at the stage of severe acute hepatitis.


Asunto(s)
Encefalopatía Hepática/etiología , Encefalopatía Hepática/prevención & control , Hepatitis Viral Humana/complicaciones , Fallo Hepático/etiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Análisis Discriminante , Femenino , Encefalopatía Hepática/sangre , Hepatitis Viral Humana/sangre , Humanos , Lactante , Fallo Hepático/sangre , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Tiempo de Protrombina , Remisión Espontánea , Estudios Retrospectivos , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad
10.
Rinsho Ketsueki ; 45(5): 397-401, 2004 May.
Artículo en Japonés | MEDLINE | ID: mdl-15199750

RESUMEN

We report herein a 21-year-old hepatitis B virus (HBV) female carrier who developed persistent fever, lymphadenopathy and pancytopenia in September of 2000. Hemophagocytes were found in the bone marrow smears. Epstein-Barr virus (EBV) serology showed positive for VCA-IgG, IgM and EB-ER and negative for EBNA. The EBV genome was detected in the peripheral blood. The patient was diagnosed as having EBV-associated hemophagocytic syndrome (EBV-AHS) and received chemotherapy. Although she was treated with lamivudine three months after the initiation of chemotherapy, she developed severe hepatitis. She recovered from the hepatitis through a combination of plasma exchange, immunosuppressive and antiviral therapies. Because of the refractoriness of her EBV-AHS to chemotherapy, she received allogeneic peripheral blood stem cell transplantation (PBSCT) from her HLA-identical brother. Hepatitis B did not recur after the PBSCT under administration of lamivudine. The EBV genome in the peripheral blood disappeared soon after the PBSCT but it was revealed again after the initiation of prednisolone for the treatment of acute GVHD. A donor lymphocyte infusion (DLI) was given on day 169 and the EBV genome copy number in the peripheral blood gradually decreased and disappeared. Although the origin of the EBV-infected cells could not be determined as being from the host or donor, DLI was a useful treatment for the recurrence of EBV infection after allogeneic stem cell transplantation for EBV-AHS.


Asunto(s)
Infecciones por Virus de Epstein-Barr/terapia , Hepatitis B/terapia , Histiocitosis de Células no Langerhans/terapia , Trasplante de Células Madre de Sangre Periférica , Adulto , Portador Sano , Femenino , Humanos , Transfusión de Linfocitos
11.
PLoS One ; 8(3): e59611, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23555725

RESUMEN

BACKGROUND & AIMS: The interferon (IFN) system plays a critical role in innate antiviral response. We presume that targeted induction of IFN in human liver shows robust antiviral effects on hepatitis C virus (HCV) and hepatitis B virus (HBV). METHODS: This study used chimeric mice harboring humanized livers and infected with HCV or HBV. This mouse model permitted simultaneous analysis of immune responses by human and mouse hepatocytes in the same liver and exploration of the mechanism of antiviral effect against these viruses. Targeted expression of IFN was induced by treating the animals with a complex comprising a hepatotropic cationic liposome and a synthetic double-stranded RNA analog, pIC (LIC-pIC). Viral replication, IFN gene expression, IFN protein production, and IFN antiviral activity were analyzed (for type I, II and III IFNs) in the livers and sera of these humanized chimeric mice. RESULTS: Following treatment with LIC-pIC, the humanized livers of chimeric mice exhibited increased expression (at the mRNA and protein level) of human IFN-λs, resulting in strong antiviral effect on HBV and HCV. Similar increases were not seen for human IFN-α or IFN-ß in these animals. Strong induction of IFN-λs by LIC-pIC occurred only in human hepatocytes, and not in mouse hepatocytes nor in human cell lines derived from other (non-hepatic) tissues. LIC-pIC-induced IFN-λ production was mediated by the immune sensor adaptor molecules mitochondrial antiviral signaling protein (MAVS) and Toll/IL-1R domain-containing adaptor molecule-1 (TICAM-1), suggesting dual recognition of LIC-pIC by both sensor adaptor pathways. CONCLUSIONS: These findings demonstrate that the expression and function of various IFNs differ depending on the animal species and tissues under investigation. Chimeric mice harboring humanized livers demonstrate that IFN-λs play an important role in the defense against human hepatic virus infection.


Asunto(s)
Quimera/inmunología , Hepacivirus/fisiología , Virus de la Hepatitis B/fisiología , Interferones/genética , Hígado/inmunología , Hígado/virología , Activación Transcripcional , Animales , Apoptosis/inmunología , Línea Celular , Humanos , Inmunidad Innata/genética , Interleucinas/genética , Hígado/citología , Hígado/metabolismo , Ratones , Polimorfismo de Nucleótido Simple , ARN Bicatenario/genética , Especificidad de la Especie
19.
Intern Med ; 48(19): 1725-30, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19797827

RESUMEN

OBJECTIVE: We investigated the risk of upper gastrointestinal (UGI) bleeding and the protective effect of concomitant anti-secretory drugs during dual antiplatelet therapy administered following implantation of drug-eluting stents (DES) for coronary heart disease. Because proton pump inhibitors (PPIs) are reported to decrease the platelet inhibitory effects of clopidogrel, we also assessed cardiovascular outcomes in patients taking thienopyridine derivatives with or without anti-secretory drug. METHODS: We retrospectively analyzed 243 patients, who underwent DES implantation between January 2006 and December 2007 and were receiving dual anti-platelet therapy post-surgery. The main outcome measurement was the presence of UGI bleeding. Cardiovascular outcomes were assessed by follow-up coronary angiography (CAG) findings. Data were collected from medical records. RESULTS: Eight cases of UGI bleeding were observed during the follow-up period, none of whom were taking anti-secretory drugs. Among the 243 cases, 108 cases were taking anti-secretory drugs: a PPI (67 cases), and an H2 receptor antagonist (41 cases). No UGI bleeding was observed among patients who were taking concomitant anti-secretory drugs. The 1- and 2-year cumulative incidences of UGI bleeding among patients who were not taking anti-secretory drugs were 4.5% and 9.2%, respectively. When CAG findings were compared between patients not taking any anti-secretory drug, taking PPI, or taking H2RA, significantly more stenotic lesions of the coronary artery were observed in the PPI-treatment group. CONCLUSION: Concomitant use of an anti-secretory agent was associated with a reduced risk of UGI bleeding. Use of PPI may be associated with an attenuation of the effect of dual antiplatelet therapy.


Asunto(s)
Enfermedad Coronaria/tratamiento farmacológico , Enfermedad Coronaria/cirugía , Stents Liberadores de Fármacos , Hemorragia Gastrointestinal/inducido químicamente , Hemorragia Gastrointestinal/prevención & control , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Angioplastia Coronaria con Balón , Aspirina/administración & dosificación , Aspirina/efectos adversos , Cilostazol , Clopidogrel , Interacciones Farmacológicas , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de la Bomba de Protones/administración & dosificación , Estudios Retrospectivos , Tetrazoles/administración & dosificación , Tetrazoles/efectos adversos , Trombosis/prevención & control , Ticlopidina/administración & dosificación , Ticlopidina/efectos adversos , Ticlopidina/análogos & derivados , Resultado del Tratamiento
20.
Biochem Biophys Res Commun ; 354(1): 154-9, 2007 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-17214962

RESUMEN

Bile acids, which have been implicated in gastrointestinal-tract cell carcinogenesis, share properties with tumor promoters in that both affect signal transduction pathways responsible for cell proliferation and apoptosis. In the present study, we demonstrate that EGFR-ERK1/2 is activated following treatment of AGS human gastric carcinoma cells with bile acids. EGFR phosphoactivation is ligand-dependent, since treatment of cells with HB-EGF antisera or CM197 (a selective inhibitor of HB-EGF) markedly inhibits deoxycholate (DC)-promoted activation. Membrane-type bile acid receptor (M-BAR)/TGR5 is a recently identified G-protein-coupled receptor (GPCR). In AGS cells, siRNAs that target M-BAR suppress DC-induced phosphorylation of EGFR. Furthermore, introduction of siRNAs targeting ADAM17 transcripts resulted in suppression of DC-induced activation of EGFR and ERK1/2. These results suggest that in AGS cells, DC transactivates EGFR through M-BAR- and ADAM/HB-EGF-dependent mechanisms.


Asunto(s)
Adenocarcinoma/metabolismo , Ácidos y Sales Biliares/administración & dosificación , Membrana Celular/metabolismo , Receptores ErbB/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Neoplasias Gástricas/metabolismo , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Humanos
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