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C Quinto

Publications and source records attributed to C Quinto.

44 records · Page 3Linked to original sources
PubMed1982

Rat preprocarboxypeptidase A: cDNA sequence and preliminary characterization of the gene.

Rat carboxypeptidase A cDNA clones have been isolated from a cDNA library prepared from pancreatic mRNA. An almost complete mRNA sequence has been deduced that predicts a polypeptide having 78% amino acid sequence homology with bovine carboxypeptidase A. The amino acid sequence of the activation and signal peptides of the carboxypeptidase A precursor were inferred from the nucleotide sequence. The cDNA was used as a probe to identify DNA fragments containing carboxypeptidase A sequences in a bacteriophage lambda library of rat genomic DNA. Heteroduplexes revealed that the DNA coding sequence occupies 5.5 kilobases and is interrupted by nine intervening sequences. The nucleotide sequence of the 5' end of the gene and the adjacent flanking region provides information on the site of initiation of transcription and the putative control regions. There is no evident relationship between the localization of intervening sequences in the gene and functional/structural domains of the protein.

Animals↗
PubMed1978

Nitrogen regulation of glutamine synthetase in Neurospora crassa.

A higher activity of glutamine synthetase (EC 6.3.1.2) was found in Neurospora crassa when NH4+ was limiting as nitrogen source than when glutamate was limiting. When glutamate, glutamine or NH4+ were in excess, a lower activity was found. Immunological titration and sucrose gradient sedimentation of the enzyme established that under all these conditions enzyme activity corresponded to enzyme concentration and that the octamer was the predominant oligomeric form. When N. crassa was shifted from nitrogen-limiting substrates to excess product as nitrogen source, the concentration of glutamine synthetase was adjusted with kinetics that closely followed dilution by growth. When grown on limiting amounts of glutamate, a lower oligomer was present in addition to the octameric form of the enzyme. When the culture was shifted to excess NH4+, glutamine accululated at a high rate; nevertheless, there was only a slow decrease in enzyme activity and no modification of the oligomeric pattern.

Culture Media↗
PubMed1978

Nitrogen source regulates glutamine synthetase mRNA levels in Neurospora crassa.

Neurospora crassa glutamine synthetase mRNA was measured by its capacity to direct the synthesis of the specific protein in a cell-free system derived from rabbit reticulocytes. N. crassa cultures grown on glutamate as the sole nitrogen source had higher mRNA activities than did those grown on glutamine. The differences were about 10-fold when polysomal RNA was used for translation and about 5-fold when either total cellular RNA or polyadenylic acid-enriched cellular RNA was used. These data indicate that in exponentially growing N. crassa, the nitrogen source regulates glutamine synthetase by adjusting specific mRNA levels.

Cell-Free System↗
PubMed1977

Neurospora crassa glutamine synthetase. Role of enzyme synthesis and degradation on the regulation of enzyme concentration during exponential growth.

The specific activity of Neurospora crassa glutamine synthetase varies according to the nitrogen source in which the organism is grown. In a poor nitrogen source such as glutamate, the specific activity of the enzyme is higher than that found in good nitrogen sources such as ammonium or glutamine. These differences in specific enzyme activity correspond to differences in enzyme concentration. The relative rates of glutamine synthetase synthesis and degradation were measured in exponential cultures grown in different nitrogen sources. The differences in enzyme concentration are explained by differences in the relative rate of enzyme synthesis.

Ammonia↗
PubMed1977

Neurospora crassa glutamine synthetase. Translation of specific messenger ribonucleic acid in a cell-free system derived from rabbit reticulocytes.

The total reticulocyte lysate cell-free protein-synthesizing system was incubated in the presence of Neurospora crassa RNA. With the aid of an antibody directed against purified N. crassa glutamine synthetase, the synthesis of a specific protein was detected. This protein precipitates with antiglutamine synthetase using both direct and indirect procedures, migrates with the same molecular weight as the monomer of N. crassa glutamine synthetase when subjected to acrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, and chromatographs as N. crassa glutamine synthetase on anthranilate-bound Sepharose. These data indicate the translation of the mRNA that codes for N. crassa glutamine synthetase. This RNA behaves as poly(A)-containing material when fractionated on oly(U)-Sepha-rose.

Animals↗
PubMedDate not supplied

Prochlorperazine-induced neuroleptic malignant syndrome.

Neuroleptic malignant syndrome can present in a variety of ways. In a review of the medical literature we could find few well-documented reports of prochlorperazine-induced neuroleptic malignant syndrome. We report such a case with its workup, recognition, and management.

Acidosis↗
PubMedDate not supplied

Bacterial contamination of musculoskeletal allografts.

Based on the indications in the literature of the transmission of highly pathogenic bacteria in musculoskeletal allograft implants, the cultural results for allografts removed and implanted in conditions of asepsis between 1997 and 2000 in BTM were analyzed: 4014 allografts (3117 from a living donor, 897 from a cadaver) and 3479 implants (2191 with allografts from living donors and 1288 with allografts from cadavers). Explanted tissues: these were positive to culture in 292 out of 3117 (9.4%) allografts from living donors; the bacteria isolated showed low pathogenicity. Out of 897 allografts 117 cadaver donors bacteria with low pathogenicity were isolated in 68 (7.6%) and high pathogenicity in 12 (1.3%). Implants: cultures were positive in 116/2191 (5.3%) implants with allografts from living donors and in 55/1288 (4.3%) implants with allografts from cadavers. The bacteria isolated are the same as those shown in the explants. In living donors contamination is similar as regards incidence and type of microorganism to that observed in surgical theatres during routine surgery. Contamination seems to be greater in allografts removed from cadavers who died as a result of trauma, in the presence of positive hemocultures, prolonged catheterization and intubation, explantation of the pelvis and removal of several organs and tissues prior to musculoskeletal allograft.

Bacteria↗