RESUMEN
Forkhead box O3 (FOXO3) is a multispecific transcription factor that is responsible for multiple and conflicting transcriptional programs such as cell survival and apoptosis. The protein is heavily post-translationally modified and there is considerable evidence that post-transcriptional modifications (PTMs) regulate protein stability and nuclear-cytosolic translocation. Much less is known about how FOXO3 PTMs determine the specificity of its transcriptional program. In this study we demonstrate that exposure of hepatocytes to ethanol or exposure of macrophages to lipopolysaccharide (LPS) induces the c-Jun N-terminal kinase (JNK)-dependent phosphorylation of FOXO3 at serine-574. Chromatin immunoprecipitation (ChIP), mRNA and protein measurements demonstrate that p-574-FOXO3 selectively binds to promoters of pro-apoptotic genes but not to other well-described FOXO3 targets. Both unphosphorylated and p-574-FOXO3 bound to the B-cell lymphoma 2 (Bcl-2) promoter, but the unphosphorylated form was a transcriptional activator, whereas p-574-FOXO3 was a transcriptional repressor. The combination of increased TRAIL (TNF-related apoptosis-inducing ligand) and decreased Bcl-2 was both necessary and sufficient to induce apoptosis. LPS treatment of a human monocyte cell line (THP-1) induced FOXO3 S-574 phosphorylation and apoptosis. LPS-induced apoptosis was prevented by knockdown of FOXO3. It was restored by overexpressing wild-type FOXO3 but not by overexpressing a nonphosphorylatable S-574A FOXO3. Expression of an S-574D phosphomimetic form of FOXO3 induced apoptosis even in the absence of LPS. A similar result was obtained with mouse peritoneal macrophages where LPS treatment increased TRAIL, decreased Bcl-2 and induced apoptosis in wild-type but not FOXO3(-/-) cells. This work thus demonstrates that S-574 phosphorylation generates a specifically apoptotic form of FOXO3 with decreased transcriptional activity for other well-described FOXO3 functions.
Asunto(s)
Apoptosis , Proteína Forkhead Box O3/metabolismo , Regulación de la Expresión Génica , Transcripción Genética , Animales , Línea Celular Tumoral , Proteína Forkhead Box O3/genética , Humanos , Ratones , Ratones Noqueados , Fosforilación , SerinaRESUMEN
The flexible sigmoidoscope is clearly the best available screening tool for colorectal cancer. It is superior to rigid sigmoidoscopy in that the flexible scope can examine longer lengths of bowel and yields a larger number of pathologic findings. The majority of colon cancers lie beyond the view of the rigid scope, which detects only about 30% of all malignant lesions.
Asunto(s)
Enfermedades del Colon/diagnóstico , Neoplasias del Colon/diagnóstico , Sigmoidoscopía/métodos , Anciano , Humanos , RiesgoRESUMEN
A 51-year-old woman with malignant ascites secondary to hepatocellular carcinoma had a peritoneovenous (LeVeen) shunt inserted with effective control of ascites and amelioration of symptoms. The results of 12 recent series evaluating the efficacy of peritoneovenous shunts in the treatment of 198 patients with malignant ascites were reviewed. Peritoneovenous shunts effectively controlled malignant ascites in 77% of patients. Complications occurred in 25%, although the majority of these were related to shunt occlusion and transient congestive heart failure.
Asunto(s)
Ascitis/etiología , Carcinoma Hepatocelular/complicaciones , Neoplasias Hepáticas/complicaciones , Derivación Peritoneovenosa , Ascitis/cirugía , Femenino , Humanos , Persona de Mediana EdadRESUMEN
The clinicopathologic features and natural history of primary sclerosing cholangitis were reviewed in 53 patients followed at the Yale Liver Center during the past 30 yr. At presentation, the mean age of patients was 46 yr, and the male to female ratio was 1.4:1. Biliary sclerosis was limited to the intrahepatic ductal system in 21% of the patients. Fifty-three percent of the patients had mild disease without portal hypertension at presentation, and 25% had no symptoms attributable to their liver disease. Long-term follow-up was available for 42 patients and averaged 56 mo. Over this period, 16 patients remained mildly symptomatic, and 11 were asymptomatic. Survival was calculated by a Kaplan-Meier life-table analysis and demonstrated that 75% of the patients were alive 9 yr after the diagnosis of primary sclerosing cholangitis. A multivariate analysis of clinical features revealed that hepatomegaly and a serum bilirubin level greater than 1.5 mg/dl at the onset of disease were independent discriminators of a poor prognosis. Patients referred to this university medical center displayed different clinical characteristics than previously reported in primary sclerosing cholangitis. A higher percentage were older, female, and asymptomatic, and more had disease limited to the intrahepatic ductal system. Survival was also considerably improved in this group of patients and suggests that the long-term prognosis for patients with primary sclerosing cholangitis may be considerably better than previously believed.
Asunto(s)
Colangitis/patología , Adolescente , Adulto , Factores de Edad , Anciano , Análisis de Varianza , Bilirrubina/sangre , Niño , Colangitis/mortalidad , Colangitis/terapia , Femenino , Estudios de Seguimiento , Hepatomegalia/etiología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Esclerosis , Factores SexualesRESUMEN
A 61-yr-old woman was found to have multicentric hepatocellular carcinoma associated with clinical hyperthyroidism. Marked elevations in serum thyroid-stimulating hormone, T4, T3, and free T4 were documented. These values increased with tumor progression. It is postulated that this patient's hepatoma produced a substance stimulating thyroid-stimulating hormone synthesis and secretion with resultant inappropriate thyroid-stimulating hormone production and thyrotoxicosis. This unusual association of hepatocellular carcinoma with clinical and biochemical evidence of hyperthyroidism and inappropriate thyroid-stimulating hormone production has not been previously reported.
Asunto(s)
Carcinoma Hepatocelular/patología , Hipertiroidismo/patología , Neoplasias Hepáticas/patología , Síndromes Paraneoplásicos/patología , Tirotropina/metabolismo , Carcinoma Hepatocelular/metabolismo , Femenino , Humanos , Neoplasias Hepáticas/metabolismo , Persona de Mediana Edad , Síndromes Paraneoplásicos/metabolismo , Tirotropina/sangre , Tiroxina/sangre , Factores de Tiempo , Triyodotironina/sangreRESUMEN
OBJECTIVE: We designed a prospective study to determine the frequency of retroperitoneal air after endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy. We sought to elucidate the relationship of retroperitoneal air with endoscopic maneuvers, clinical findings, the length of sphincterotomy, and the time spent during the procedure. We also endeavored to determine the importance of retroperitoneal air and its most appropriate clinical management. METHODS: Twenty-one consecutive patients who had undergone ERCP with sphincterotomy had abdominal computed tomography (CT) examinations within 24 h after completion of the procedure. The CT findings were unknown to the clinicians, and none of the patients received postprocedural antibiotics. RESULTS: Six (29%) of 21 patients exhibited CT findings of retroperitoneal air. All six patients had uneventful postprocedural courses, and none had abnormal clinical signs or symptoms. The occurrence of retroperitoneal air was not influenced by the presence of hyperamylasemia, the duration of the procedure, or the length of the sphincterotomy. CONCLUSIONS: Retroperitoneal air is not an uncommon finding after ERCP with sphincterotomy. Moreover, the finding of retroperitoneal air in the absence of physical findings, is not a cause for alarm and does not require surgical intervention.
Asunto(s)
Aire , Colangiopancreatografia Retrógrada Endoscópica , Espacio Retroperitoneal/diagnóstico por imagen , Esfinterotomía Endoscópica , Adulto , Anciano , Anciano de 80 o más Años , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Esfinterotomía Endoscópica/efectos adversos , Factores de Tiempo , Tomografía Computarizada por Rayos XRESUMEN
A 31-year-old white man with suspected aspiration pneumonia complicated by multiple pulmonary abscesses had profound neutropenia during a course of high-dose benzylpenicillin therapy for suspected bacterial endocarditis. Antigranulocyte antibodies were identified in the patient's serum. Leukopenia is an uncommon but potentially serious complication of therapy with this drug. We recommend weekly monitoring of blood counts during prolonged therapy with any beta-lactam antibiotic.
Asunto(s)
Agranulocitosis/inducido químicamente , Neutropenia/inducido químicamente , Penicilina G/efectos adversos , Adulto , Endocarditis Bacteriana/complicaciones , Endocarditis Bacteriana/tratamiento farmacológico , Humanos , Absceso Pulmonar/complicaciones , Absceso Pulmonar/tratamiento farmacológico , Masculino , Neumonía por Aspiración/complicaciones , Neumonía por Aspiración/tratamiento farmacológicoRESUMEN
In vivo 31phosphorus nuclear magnetic resonance spectroscopy was used to measure the hepatic metabolic state in various groups of rats given ethanol, a control liquid diet or a solid chow diet. The use of selective presaturation pulses applied to the broad phosphorus resonances of immobile phospholipids permitted reliable determination of ATP/ADP ratios by quantitation of the ATP-beta and ATP-gamma peak areas. ATP/ADP ratios were depressed by both techniques in rats chronically ingesting ethanol compared to pair-fed animals consuming the control liquid diet. These differences were observed regardless of whether ethanol feeding was continued up to the time of investigation or whether it was discontinued for 24 hr prior to study. Acute alcohol administration in chow-fed rats, not previously ingesting ethanol, did not lower hepatic ATP/ADP ratios by either methodology. In all cases, liver ATP/ADP ratios assessed by 31phosphorus nuclear magnetic resonance spectroscopy were higher than those measured by high-performance liquid chromatography. However, parallel decreases in hepatic ATP/ADP ratios were observed with chronic ethanol consumption by both 31phosphorus nuclear magnetic resonance spectroscopy and the biochemical method, confirming the utility of in vivo 31phosphorus nuclear magnetic resonance spectroscopy for assessment of the hepatic bioenergetic status. The difference in absolute ATP/ADP ratios by the two methods may to some degree be explained by binding effects of ADP with proteins or mitochondrial membranes, rendering it partially invisible to nuclear magnetic resonance or alternatively, by breakdown of high energy phosphate bonds with freeze clamp extraction.
Asunto(s)
Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Etanol/farmacología , Hígado/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Etanol/administración & dosificación , Hígado/efectos de los fármacos , Hígado/ultraestructura , Espectroscopía de Resonancia Magnética , Masculino , Microscopía Electrónica , Isótopos de Fósforo , Ratas , Ratas EndogámicasRESUMEN
Five patients had amiodarone hepatotoxicity detected on routine biochemical monitoring. Symptoms attributable to hepatotoxicity were minimal or absent; reversible hepatomegaly was seen in two patients, whereas three patients had signs of nonhepatic amiodarone toxicity before or with hepatotoxicity. Serum aminotransferase levels were elevated in all patients and alkaline phosphatase levels in four; no patient had hyperbilirubinemia or prolongation of the prothrombin time. Light microscopy showed steatosis, cellular degeneration, and cellular necrosis in the biopsy samples of four patients, whereas the fifth patient's sample had a granulomatous injury pattern. Electron microscopic study of liver tissue done in two patients showed phospholipid-laden lysosomal lamellar bodies. These findings suggest that both toxic and hypersensitivity liver injury can occur in response to amiodarone. The presence of phospholipid-laden lysosomal lamellar bodies may help differentiate amiodarone hepatotoxicity from alcoholic liver disease or other causes of hepatic steatosis.