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

Prostaglandins (PGE1) and dibutyryl cyclic AMP (dBc AMP) induce similar morphological changes in astrocytes obtained in primary cultures. PGE1 and dBc AMP increased 2 enzymes of GABA and glutamate metabolism, GABA-T and AAT, but did not modify GDH and GLN-S. Prostaglandins probably affect the cAMP content of glial cells and act in the same way as dBc AMP on glial cell differentiation.
 ...
PMID:Effect of prostaglandins and dibutyryl cyclic AMP on the morphology of cells in primary astroglial cultures and on metabolic enzymes of GABA and glutamate metabolism. 625 71

Alpha 1-antitrypsin has been examined in formalin-fixed, paraffin-embedded liver specimens from Greek patients with cirrhosis (35 cases) and hepatoma (55 cases) by peroxidase-antiperoxidase (PAP) method. Ring-like AAT globules were found in the non-neoplastic cells in 12% of the cases of hepatoma and in 11% of the cases of cirrhosis. Atypical globules were seen in neoplastic cells in 5.4% of the cases of hepatoma and in 17% of the cases of liver cirrhosis. A diffuse fine granular pattern of AAT distribution was present in 31% of the cases of hepatoma in the neoplastic cells and in 27% of those in the non-neoplastic cells. The relatively high incidence of ring-like AAT-globules, and of atypical globules in cases of hepatoma and cirrhosis is not in agreement with the extremely low gene frequency of Z allele in a Greek population of patients with cirrhosis and hepatoma. Thus, there is some doubt whether AAT-globules in the liver represent a histopathologic marker of genetically determined AAT deficiency. A relationship between AAT deposits and the degree of differentiation of hepatoma was noted in this series. AAT-positive cells were found in 55% of moderately differentiated, in 29% of highly differentiated and in 20% of poorly differentiated hepatomas.
 ...
PMID:Demonstration of alpha 1-antitrypsin in paraffin sections of hepatoma and cirrhosis. 629 75

The activities of adenosine deaminase, purine nucleoside phosphorylase, membrane 5'-nucleotidase and DNA content in thymus and spleen lymphocytes as well as the immune function of T and B lymphocytes of the spleen of C3HA mice with o-AAT-induced hepatomas were studied 1, 3 weeks and 3, 8, 12 months after o-AAT treatment was instituted. In the early stages of the hepatocarcinogenesis (up to 3 months), the elevation of the activity of all the enzymes and DNA content in thymocytes and T and B lymphocytes was observed. These changes coincided with the enhancement of the immune responses that manifested in the increased content of PFC, EA-RFC and high response to PHA and Con A. In the late stages, the decreased activities of purine nucleosides and nucleotide metabolizing enzymes correlated with disturbances of lymphocyte differentiation and lowering of the host immune response.
 ...
PMID:[Changes in purine metabolism and in the immune response in the thymic and splenic lymphocytes of C3HA mice during chemical hepatocarcinogenesis]. 633 63

Amino acid sequence and composition data of Escherichia coli dnaG primase protein and its tryptic peptides have confirmed that the dnaG gene contains an unusually high number of codons that are not frequently used in most E. coli genes. In 25 E. coli proteins analyzed the codons AUA, UCG, CCU, CCC, ACG, CAA, AAT, and AGG are infrequently used, occurring as 4% of the total codons in the reading frame and 11% and 10% in the nonreading frames. In dnaG they occur as 11% in the reading frame and 12% in the nonreading frames. The rpsU and rpoD genes, which flank the dnaG gene [Smiley, B. L., Lupski, J. R., Svec, P. S., McMacken, R. & Godson, G. N. (1982) Proc. Natl. Acad. Sci. USA 79, 4550-4554], however, have normal codon usage. Translational modulation using isoaccepting tRNA availability may therefore be part of the mechanism of keeping the dnaG gene expression low, while expression of the adjacent rpsU and rpoD genes on the same mRNA transcript is high.
 ...
PMID:Evidence for use of rare codons in the dnaG gene and other regulatory genes of Escherichia coli. 633 95

Cytosolic aspartate aminotransferase (c-AAT) was purified to homogeneity from porcine heart and immunized to rabbit for production of antiserum. The purity of this enzyme protein and the specificity of its antibody were judged by silver-stained-sodium dodecyl sulfate slab gel, Western blot transfer technique, and double immunodiffusion. The antibody against porcine heart c-AAT was found to cross-react with rat c-AAT but not with nine other different enzymes from the heart, liver, and muscle. Affinity purified antibody was used to localize this isoenzyme in the rat heart, liver, kidney, and cerebellum by indirect immunoperoxidase method. It was found that, in the rat heart muscle, c-AAT reaction product was present as a linear structure parallel to the muscle fiber and along the sarcolemma. Some cardiac muscle fibers contain more reaction products than the others. In the liver, reaction product was seen unevenly distributed in the hepatocytes. The Kupffer cells and endothelia were less stained. Most of the tubular epithelia of the loop of Henle in the kidney were intensely stained. But other tubular epithelia including convoluted and collecting tubules were sporadically and less stained. The basket and stellate cells and their neuronal processes and terminals in the cerebellum were markedly stained, but the Purkinje and granule cell bodies were weakly stained. For comparison of the staining intensity with enzyme activity in each organ, the c-AAT enzyme activity was simultaneously determined in those organs. This study indicates that the presence of c-AAT is specific in different organs and tissues.
 ...
PMID:Production and characterization of an antibody to cytosolic aspartate aminotransferase and immunolocalization of the enzyme in rat organs. 640 65

This work was undertaken as part of a search for well-characterized glycoprotein models in which both the oligosaccharide structure, the number of oligosaccharide chains, and the precise location of these chains in the protein are known. On the basis of the fact that high-affinity ligand binding sites have been defined precisely for several proteins in terms of both number and relative location, the hypothesis to be tested was that if oligosaccharide chains were covalently attached to such high-affinity ligands, they would be specifically bound in the ligand sites of the appropriate protein, thus permitting the preparation of neoglycoproteins of precise predetermined oligosaccharide valency and topography. To test this hypothesis, pyridoxal 5'-phosphate was reductively (NaB3H4) aminated with the alpha-amino group of the asparagine oligosaccharide Man6-GlcNAc2-Asn from ovalbumin. When the resulting phosphopyridoxylated oligosaccharide (PG) was added to the apo form of aspartate aminotransferase (AAT; EC 2.6.1.1, the cytosolic enzyme from pig heart, consisting of two subunits and containing two coenzyme binding sites), a 2:1 (PG-AAT) complex was formed which could be characterized on the basis of tritium content, the absorbance and fluorescence of the pyridoxamine phosphate moiety of PG, and the concanavalin A binding properties acquired by AAT through the incorporation of the oligosaccharide. As expected from the established properties of the holoenzyme, the AAT-PG complex is stable in the absence of phosphate or vitamin B6 derivatives and can be dialyzed for 24 h without any significant loss of PG. According to the three-dimensional model of AAT, the oligosaccharide chain of PG should be partially masked in the coenzyme binding pocket.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Neoglycoproteins: preparation of noncovalent glycoproteins through high-affinity protein- (glycosyl) ligand complexes. 646 43

The frequency of thyroid antibodies was investigated in 1314 healthy blood donors. Twenty-three of 870 males (2.6%) were positive for thyroglobulin antibody (TA), 34 (3.9%) for thyroid microsomal antibody (MA) and 19 (2.2%) for both TA and MA. Thirty-four of 484 females (6.2%) were positive for TA, 46 (9.5%) for MA and 29 (6.0%) for both TA and MA. Eighty-six of 1314 blood donors were positive for TA and/or MA. There was no difference in liver function tests between AAT and controls. In females, the incidence of thyroid antibodies tended to increase with age. However, the subjects aged under 19 showed another peak of incidence of thyroid antibodies. The values of total T4, T3 and free T4 were not different between 86 subjects with positive thyroid antibodies (asymptomatic autoimmune thyroiditis, AAT) and 86 sex- and age-matched controls without thyroid antibodies, whereas serum TSH of AAT was significantly higher than that of controls. Nine of 86 (10.5%) subjects with AAT had apparently increased basal TSH level.
 ...
PMID:Thyroid antibodies in healthy blood donors. 653 99

Treatment with synthetic MDP inhibited growth of transplantable, chemically induced tumors in syngeneic mice. The tumor-inhibitory effect was dependent on the schedule of MDP administration. Growth of SC transplants of a nonmetastasizing, MC-induced fibrosarcoma, MC11, was inhibited by local treatment with 200 micrograms and 1,000 micrograms MDP given SC 5-7 weeks before challenge. Treatment with lower (10 micrograms and 100 micrograms) doses of MDP and shorter (1-4 weeks) time intervals was not effective. Single doses of MDP (10-1,000 micrograms) 1-3 weeks after challenge had no effect. Growth of IV-inoculated, metastasizing AAT-induced hepatoma A was inhibited by IV injections of 20 micrograms MDP given 1 and 2 days prior to the challenge. Significant increases in the survival of hepatoma-bearing mice were observed only after injections of MDP incorporated in multilamellar liposomes.
 ...
PMID:Inhibition of tumor growth in mice treated with synthetic muramyl dipeptide. 656 71

A 10.5 year old girl with liver cirrhosis due to AAT-deficiency (Pi type ZZ) developed cyanosis and clubbing of finger and toes. Clinical aspect of a cyanotic heart disease appeared with 10 years, 7 years after diagnosis of cirrhosis. By contrast echocardiography existence of intrapulmonary arterio-venous shunts was demonstrated. When determined during the first year of life, serum-alpha-1-globulin-fraction of the patient was found to be normal. The result indicates, that even in severe AAT-deficiency of Pi type ZZ direct determination of AAT is necessary for diagnosis of the disease.
 ...
PMID:[Liver cirrhosis due in alpha-1-antitrypsinin deficiency and development of an arteriovenous shunts of the lungs]. 660 21

The Dukes' and TNM systems for staging carcinoma of the colon and rectum are still the best pathologic classifications, but they do not apply to all patients and do not distinguish between patients who will die and patients who will be cured by the same therapeutic procedure. A new approach to this problem should be to establish a biochemical automatic classification, complementary to the morphologic one, which allow us to classify every patient before and after the first and subsequent treatments. By using several nonspecific tumor markers, such as CEA, AAT, AF, AAG, GGT and transferrine, a discriminant analysis was executed among the groups of patients with LD, RD and DD. Our initial results with only 12.8 per cent of incorrect classifications, that is patients classified in a less advanced group, suggest that this system may be quite useful in order to select those patients with carcinoma of the rectum who should benefit from preoperative radiotherapy as well as those who should receive adjuvant therapy after the first treatment. On the other hand, for patients classified in a more advanced group than the pathologic grading, we may well be able to identify those patients with occult disease for which the frequency of revisions should be shorter.
 ...
PMID:Automatic preoperative classification of carcinoma of the colon and rectum. 671 Mar 17


<< Previous 1 2 3 4 5 6 7 8 9 10