Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.6.1.1 (aspartate aminotransferase)
 21,665 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was performed to investigate modifications in the serum bilirubin forms, hepatobiliary enzymes, and some glycoproteic substances in patients during the course of extrahepatic cholestasis (stage A) and following its clinical resolution (stage B). The series consisted of 16 patients: 11 had main bile duct stones; two, benign stenosis of the main bile duct; and three, main bile duct cancer. Cholestasis resolved spontaneously in one case, under endoscopy in two, and following surgery in 13. Five patients with liver cirrhosis and a picture of intrahepatic cholestasis following anesthesia were also investigated. Serum bilirubin forms were measured using van den Bergh's method and the alkaline methanolysis-HPLC procedure; the mono- and di-conjugated forms were considered together in the overall evaluation of the results. The hepatobiliary enzymes (ALP, GGT, and AST) were increased at stage A and significantly decreased at stage B. Similar patterns were observed in total (TB), unconjugated (UB), and conjugated bilirubin (CB) and in the percentage of CB out of TB (% CB). In the majority of patients, % CB at stage B was lower than at stage A, whereas in subjects with a high initial UB value, a different % CB pattern was observed. The direct bilirubin percentage (% DB), on the other hand, had a different pattern, and the variations between stages A and B were not significant. The pathophysiological bilirubin pattern was similar in patients with intrahepatic cholestasis. At stage A, in a number of patients the levels of glycoproteic substances (CA 19-9, TPA and ferritin) were raised, but at stage B they tended to decrease towards the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Alterations in bilirubin metabolism during extra- and intrahepatic cholestasis. 160 Mar 31

Enzymatic sulfation of N-hydroxylated arylamines by mammalian hepatic cytosol sulfotransferases (AST; EC 2.8.2.1) is an important metabolic step which generates ultimate carcinogens. The metabolic activity of AST IV, the putative isozymic form of AST primarily responsible for catalyzing N-hydroxy-2-acetylaminofluorene sulfation, is modulated during 2-acetylaminofluorene (AAF)-induced rat hepatocarcinogenesis. To characterize the molecular mechanisms regulating the differential expression of AST IV, we have assessed polyadenylated mRNA derived from the livers of Sprague-Dawley rats undergoing different stages of AAF hepatocarcinogenesis for general in vitro translation capacity and specific expression of AST IV and albumin. Following 1 and 3 cycles of a cyclical feeding regimen (3 weeks 0.05% AAF, then 1 week basal diet), the mRNA capacity for translation was lowered and the expression of AST IV and albumin was down-regulated about 2-fold each but recovered to normal levels when treated rats were subsequently placed on basal diet for 3 continuous weeks. Cytosolic albumin levels were determined by Western blot analysis to be lowered about 1.5-2-fold. In contrast, however, mRNA from rats on basal diets for 3 weeks subsequent to cycle 5 of the feeding regimen recovered only about 50% of the capacity for AST IV expression, although overall translation capacity and albumin expression returned to normal levels. This pattern of reversible expression, followed by irreversible expression of AST IV at early and late stages of AAF hepatocarcinogenesis, respectively, provides the first evidence correlating the modulation of hepatic mRNA capacity for AST IV expression with differential cytosolic AST IV activity in the AAF hepatocarcinogenesis model. The results further suggest that during early stages in hepatocarcinogenesis modulation of mRNA protein synthesis functions may be a critical factor in AAF-mediated lowering of AST IV expression, while other persistent genetic lesions are likely playing a more significant role at the late stages of the carcinogenic process leading to neoplastic transformation of initiated hepatocytes.
Cancer Res 1991 Jan 15
PMID:Modulation of hepatic mRNA translation activity and specific expression of arylsulfotransferase IV during acetylaminofluorene-induced rat hepatocarcinogenesis. 167 Jul 61

The effects of geniposide pretreatment on both hepatic aflatoxin B1 (AFB1)-DNA binding and AFB1 hepatotoxicity in rats has been examined. For these studies, male Sprague-Dawley rats were treated with AFB1 (2 mg/kg) by i.p. administration, and the different degrees of hepatic damage were revealed by the elevations of levels of serum marker enzymes such as aspartate aminotransferase (AST), alanine amino-transferase (ALT) and gamma-glutamyltranspeptidase (gamma-GT). After pretreatment of animals with geniposide (10 mg/kg) daily for 3 consecutive days, the enzyme elevations were significantly suppressed. This suggested that the geniposide possessed chemopreventive effects on the early acute hepatic damage induced by AFB1. Under these experimental conditions, consistent elevation of the activities of glutathione S-transferase (GST) and gamma-glutamylcysteine synthetase but not glutathione peroxidase (GSH-Px) and gamma-glutamyltranspeptidase were observed. Treatment of rats with geniposide significantly lowered hepatic GSH and GSSG levels, but the ratio of GSH to GSSG was not changed. Geniposide treatment also decreased AFB1-DNA adduct formation in AFB1-treated animals. From these results, we suggest that the protective effect of geniposide on AFB1 hepatotoxicity in rats might be due to the hepatic tissues' defense mechanisms that involve the enhanced GST activity for AFB1 detoxication and induction gamma-glutamylcysteine synthetase for GSH biosynthesis.
Cancer Lett 1991 Nov
PMID:Suppressive effect of geniposide on the hepatotoxicity and hepatic DNA binding of aflatoxin B1 in rats. 168 34

The response and survival of 26 patients with liver metastases from breast cancer, who received OK-432-combined adoptive immunotherapy from 1984 to 1990, were evaluated. OK-432-combined adoptive immunotherapy was comprised sequential treatment via the hepatic artery with a streptococcal preparation, OK-432 (1-5 KE), and adoptive transfer of lymphocytes expanded in T-cell growth factor and sonicated tumor extract antigen. Seventeen (65%) patients responded to the therapy. The median survival time of all patients after treatment was 13 months (range, 2-63 months). Of the 20 prognostic factors analyzed, performance status (PS) alone was related to response (P less than 0.01). The response rate of the patients with a PS of 0-2 was 83% but only 25% in those with a PS of 3 or 4. In univariate analysis, 11 factors significantly influenced the survival: tumor response; size of primary tumor; menopausal status; PS; serum bilirubin, albumin, lactate dehydrogenase and glutamate-oxalate transaminase (aspartate aminotransferase); the extent of liver involvement; and the number and the proliferation rate of transferred lymphocytes. The MST was 22.8 months for the responders versus 2.8 months for the nonresponders (P less than 0.01). In multivariate analysis, the most important factor associated with survival was the tumor response, as well as PS, liver involvement, lactate dehydrogenase and albumin. These results suggest that OK-432-combined adoptive immunotherapy can be considered a candidate for a randomised control study and these factors should be used for stratification.
J Cancer Res Clin Oncol 1992
PMID:Factors influencing the response and survival of patients with liver metastases from breast cancer receiving OK-432-combined adoptive immunotherapy. 173 36

Ondansetron, a new 5-HT3 receptor antagonist, has been compared with high-dose metoclopramide in the control of acute emesis (24 h) induced by cisplatin (greater than or equal to 100 mg/m2). Ondansetron, given as three intravenous doses (0.15 mg/kg) 4-hourly, was superior to six intravenous doses of metoclopramide (2.0 mg/kg) in the control of acute emesis. Complete control of emesis was achieved in 40% of patients receiving ondansetron compared to 30% of patients receiving metoclopramide (P = 0.07); complete or major control (0-2 emetic episodes) was achieved in 65% and 51% of the patients receiving the two treatments respectively (P = 0.016). Patients entered in the acute emesis study who experienced no emesis or up to two episodes were randomised between placebo and ondansetron on day 2 to evaluate the control of delayed emesis up to day 5. Complete control of persistent or delayed emesis over days 2-5 was achieved in 59-78% of patients with oral ondansetron (16 mg t.d.s.) compared to 39-50% of patients receiving oral placebo. These differences failed to reach statistical significance except on day 4. Some patients with complete or major control of emesis on their first course of chemotherapy subsequently received further courses of ondansetron (median 3 courses; range 2-10) on a non-comparative basis. Similar control was achieved in 85% of courses. There may be some reduction in the degree of control with subsequent courses. Of 44 patients with complete control at cycle 1, 19 (44%) were emesis free and 3 (7%) experienced 1-2 episodes with cycle 3, though patients were sometimes withdrawn before cycle 3 for reasons other than inadequate anti-emetic control. Efficacy with successive courses can only be established in a prospective comparative trial. Both treatments were well tolerated but ondansetron caused significantly greater transient asymptomatic elevations in ALT/AST (P = 0.003/0.005). Acute dystonic reactions (2 patients) and akathisia (10 patients) occurred with metoclopramide only (P = 0.002). The role of ondansetron in the control of delayed emesis requires further study.
Eur J Cancer 1991
PMID:Progress in the control of acute and delayed emesis induced by cisplatin. 183 33

We observed significantly reduced serum alpha 2-HS glycoprotein concentrations in patients with acute lymphocytic, acute nonlymphocytic, chronic granulocytic and chronic myelomonocytic leukemias, Hodgkin's and non-Hodgkin's lymphomas, myelofibrosis, and multiple myeloma, but not in patients with chronic lymphocytic leukemia and polycythemia vera, as compared with healthy controls. We followed the serum level of the protein for 18 months. Patients with infectious complications, those receiving cytostatic treatment, and those in the preterminal period had further reduced serum alpha 2-HS glycoprotein levels. The reduction of serum alpha 2-HS glycoprotein concentration was primarily due to decreased production caused by infiltration of the liver, a hepatotoxic effect of cytostatic treatment, and, to a lesser degree, to increased consumption. We found statistically significant negative correlations between serum alpha 2-HS glycoprotein concentration and erythrocyte sedimentation rate, serum aspartate aminotransferase and alkaline phosphatase activities, and IgG and IgM concentrations. The determination of the alpha 2-HS glycoprotein concentration is useful for the assessment and follow-up of the clinical status and therapy of patients with hematological malignancies and also has prognostic significance.
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PMID:Serum alpha 2-HS glycoprotein concentration in patients with hematological malignancies. A follow-up study. 195 51

In vivo studies with L-[13N]glutamate in the Walker 256 carcinosarcoma implanted under the renal capsule of female Sprague-Dawley rats demonstrate that uptake of glutamate and the rate of incorporation of the nitrogen label from this amino acid into metabolites is slower in the tumor than in nontumorous kidney tissue. Glutamate dehydrogenase, glutaminase, and alanine aminotransferase activities are significantly lower within the tumor than within the adjoining kidney. However, the tumor expresses high levels of aspartate aminotransferase, attesting to the importance of this enzyme in the metabolism of glutamate. Indeed, high performance liquid chromatographic analysis showed that the principal metabolic fate of label derived from L-[13N]glutamate in the tumor is incorporation into aspartate. Measurement of specific activity ratios of glutamate to aspartate shows that the transfer of nitrogen from glutamate to aspartate is rapid and that equilibration of label among components of the aspartate aminotransferase reaction is attained within minutes after tumor uptake. Analyses of the nontumorous portion of the implanted kidney also showed that aspartate is the major recipient of glutamate nitrogen. However, high performance liquid chromatographic analyses of deproteinized tissue revealed that glutamine and ammonia are also significant 13N-labeled metabolites formed from L-[13N]glutamate within the kidney. Proportionately lower amounts of these labeled metabolites were found in the tumor.
Cancer Res 1990 Aug 15
PMID:Short-term metabolic fate of L-[13N]glutamate in the Walker 256 carcinosarcoma in vivo. 197 67

The aim of this study was to produce large liver tumors reliably, and to diagnose the tumors during development. Therefore, New Zealand white rabbits were treated with N-nitrosodiethylamine orally three times per week by gavage and were examined by clinical-chemical assay at regular intervals during the average treatment period of 14 months. The total cumulative dose was 1200 mg N-nitrosodiethylamine over 14 months. After a short treatment period the initial dose of 3 mg/kg had to be reduced to 1.5 mg/kg. In all 11 treated animals (100%) liver tumors were seen at the end of the study. Four control animals did not show any neoplastic changes. Clinical parameters investigated were for an assessment of liver function, total protein, urea, creatinine, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, albumin and neuraminic acid as well as some serum electrolytes. The in vivo diagnosis of liver tumors based on changes in these parameters proved to be relatively unreliable. The liver enzyme tests and urea concentration only yielded significant changes when the liver tumors were very large. Changes in neuraminic acid levels were the most reliable indicator for the presence of a liver tumor in this animal model. In the 11 treated animals, serum values of this marker increased towards the end of the study by an average of 300 mg/dl. The induced tumors were mainly hepatocellular carcinomas. Only in 1 animal was a hepatocellular adenoma found. Further primary tumors diagnosed were six adenomas in the kidneys and two uterus adenomas, as well as nasal cavity tumors (two papillomas, one carcinoma, one adenoma and one adenocarcinoma). In 70% of the treated rabbits the hepatocellular carcinomas had metastasized to the lungs.
J Cancer Res Clin Oncol 1991
PMID:Diethylnitrosamine-induced metastasizing hepatocellular carcinomas in New Zealand white rabbits. A tumor model for clinical investigations. 200 10

The clinical records of 312 consecutive patients with liver metastases from breast cancer were reviewed. The primary tumours were commonly poorly differentiated, although the majority were steroid receptor positive. At diagnosis of liver metastases, 60% of patients had hepatomegaly, 13% were jaundiced and 7% had ascites. A raised serum aspartate transaminase (AST) was the most common biochemical abnormality (84%), with 54% of patients having an AST of more than twice the upper limit of normal. The median survival from the time of diagnosis of liver metastases was 3.8 months. No feature existing prior to the development of liver metastases influenced subsequent survival. The presence of jaundice (P less than 0.001), ascites (P = 0.01) or hepatomegaly (P = 0.01) were all associated with a particularly poor prognosis. While any degree of elevation of bilirubin (P less than 0.001) or alkaline phosphatase (P = 0.003) was unfavourable, a raised AST alone was not predictive of shorter survival. AST only influenced survival significantly when above twice the upper limit of normal (P less than 0.001), with prognosis then progressively worsening the more elevated the level. Multivariate analysis using the Cox model suggested that the degree of elevation of AST was the single most important prognostic factor for survival after the diagnosis of liver metastases.
Eur J Cancer 1990
PMID:Liver metastases from breast cancer: the relationship between clinical, biochemical and pathological features and survival. 214 44

Several studies of small cell lung cancer (SCLC) treatments have been performed in the United Kingdom. In some, prognostic factor analyses were carried out but the results were not entirely consistent. The Lung Cancer Subcommittee of the United Kingdom Coordinating Committee on Cancer Research (UKCCCR) consequently initiated an overview of these studies with the aim of identifying the important prognostic factors using a large number of patients. Information on almost 4,000 patients was available, but it was necessary to perform analyses on smaller subsets because the variables recorded in individual studies were inconsistent. A number of variables contributed significantly to the prediction of likely survival over the 6 months after starting treatment, but performance status (PS), alkaline phosphatase (AlkP) and disease stage were shown to be the most important; aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) may also be useful. A prognostic index was devised for this initial period and validated using independent data. For patients who survived the first 6 months, the pre-treatment variables important for prognosis in the 6-24 month period were stage, PS and plasma sodium (Na). The Subcommittee recommends that performance status, disease stage, AlkP, Na, AST and LDH should be measured in all future SCLC studies to assist comparisons between studies and possibly the selection of patients for different treatment strategies. The additional recording of five other variables would allow a more definitive overview to be performed at some future date.
Br J Cancer 1990 Apr
PMID:An overview of prognostic factors in small cell lung cancer. A report from the Subcommittee for the Management of Lung Cancer of the United Kingdom Coordinating Committee on Cancer Research. 215 8


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