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Biomedical subjects

J Bautista

Publications and source records attributed to J Bautista.

At least 73 records · Page 4Linked to original sources
PubMed1989

Implication of lysine residues in the loss of enzymatic activity in rat liver 6-phosphogluconate dehydrogenase found in aging.

During aging, there is a decrease in the activity of the 6-phosphogluconate dehydrogenase enzyme in rat liver. The "old" 6-phosphogluconate dehydrogenase enzyme is about 26% less active than the "young" enzyme. In this paper, some biochemical and chemical properties of this enzyme are studied. 2,4,6-Trinitro-benzenesulfonic acid measurements indicate that the old enzyme has 11 lysine residues less than the young enzyme. The proteolysis with trypsin produces more peptides in the young enzyme than in the old one. However, similar numbers of peptides were produced when endoproteinase Arg-C was used on both enzymes. Moreover, the treatment of the young enzyme with ascorbate for 15 min produces the loss of 8 lysine residues. These results suggest that during aging there is a modification of the lysine residue, and this could be involved in the loss of its enzymatic activity.

Aging↗
PubMed1989

Cyst of the septum pellucidum and Korsakoff's psychosis.

Noncommunicating cysts of the septum pelludicum are rare and diagnostic experience with CT scan is scanty. They may cause hydrocephalus because of obstruction of Monro's foramina. In this report we describe a young patient with acute Korsakoff's syndrome. The CT scan revealed a cyst of the septum pellucidum without hydrocephalus. Surgery disclosed a noncommunicating cyst compressing structures of the limbic system. After surgery symptoms disappeared.

Adult↗
PubMed1989

[Herpes zoster ophthalmicus with contralateral hemiplegia].

A 57-year-old patient nonimmunosuppressed who had zoster ophthalmicus associated to contralateral hemiplegia is presented. We noticed on the CT scan an infarction of left caudate nucleus, as well as in the angiography signs of vasculitis. We comment on the clinical and diagnosis features and suggest possible benefit effects of the treatment with acyclovir.

Acyclovir↗
PubMed1989

Type II collagen defects in the chondrodysplasias. I. Spondyloepiphyseal dysplasias.

The spondyloepiphyseal dysplasias (SEDs) and spondyloepimetaphyseal dysplasias (SEMDs) are a heterogeneous group of skeletal dysplasias (dwarfing disorders) characterized by abnormal epiphyses, with and without varying degrees of metaphyseal irregularities, flattened vertebral bodies, and myopia. To better define the underlying cause of these disorders, we have analyzed the collagens from costal cartilage from several of these patients, using SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and high-performance liquid chromatography (HPLC) of intact chains and cyanogen bromide (CNBr) peptides and amino acid analysis. In almost all of the patients in this study group, the type II collagen exhibited a slower electrophoretic mobility when compared with that in normal controls. The mobility of many, but not all, of the CNBr peptides was also retarded. Peptides near the amino terminus were almost always altered, while the mobility of peptides close to the carboxyl terminus were normal in all but the severely affected cases. Analysis of the CNBr peptides on an HPLC sieving column confirmed that the electrophoretically abnormal peptides were of a higher molecular weight than were control peptides. Amino acid analysis indicated that the abnormal collagens have a higher ratio of hydroxylysine to lysine than does control collagen, suggesting that overmodification may be involved in the altered mobility. Our results are consistent with a defect in the collagen helix that results in overmodification of the molecule from that point toward the amino terminus. We propose that some forms of SED and SEMD are associated with abnormalities in type II collagen that results in delayed helix formation and consequent overmodification of the collagen. Cases of SED fit onto a continuous spectrum of clinical severity that correlates positively with both the extent of alteration and the proximity of the defect to the carboxyl terminus.

Adolescent↗
PubMed1988

Possible involvement of histidine residues in the loss of enzymatic activity of rat liver malic enzyme during aging.

During aging there is a decrease in activity of the malic enzyme in rat liver. The "old" malic enzyme is about 36% less active than the "young" enzyme. Some properties and modifications of amino acid residues are studied here (--SH, arginine, methionine, histidine, lysine) to try and check on the existence of any relationship between them and the loss of enzymatic activity during aging. Diethyl pyrocarbonate measurements indicate that the old enzyme has 1 histidine residue less than the young enzyme. Moreover, the treatment of the young enzyme with ascorbate for 15 min produces the loss of 36% of the enzymatic activity and the loss of 1.2 histidine residues. These results suggest that during aging the modification of the histidine residue could be involved in the loss of its enzymatic activity.

Aging↗
PubMed1983

NADPH/NADP+ ratio: regulatory implications in yeast glyoxylic acid cycle.

The utilization by yeast of two carbon sources is carried out through the operation of the glyoxylic acid cycle. Kinetic acid from the isocitrate transforming enzymes suggest that the flow of isocitrate through the glyoxylic acid cycle depends upon the inhibition of the isocitrate decarboxylating enzymes. Both isocitrate dehydrogenases are inhibited by a mixture of glyoxylate + oxaloacetate, but for the reasons described in the text we consider that this inhibition is of no physiological significance. On the other hand, we have found that NADPH is a competitive inhibitor of NADP-isocitrate dehydrogenase with respect to NADP+, with a KI similar to its KM. It also produces an additive effect on the NADH-produced inhibition of NAD-isocitrate dehydrogenase. We propose NADPH as the compound that channels the utilization of isocitrate into the glyoxylic acid cycle. This is supported by the finding of an increased NADPH/NADP+ ratio in acetate grown yeast with respect to glucose grown cells.

Glyoxylates↗
PubMed1983

Dialysis myopathy. Report of 13 cases.

Thirteen patients hemodialyzed for chronic renal insufficiency developed progressive paresis of the proximal musculature. Biopsies of the deltoid muscles of ten patients showed selective atrophy of type 2 fibers, the cause of which seems to be related to the osteomalacia present in those patients. Purification of the water for dialysis prior to the procedure prevents the muscle alteration: however, once the lesion is established only renal transplant will permit recovery of the muscle strength of the patient.

Adult↗
PubMed1983

Facilitating myasthenic syndrome and quadriceps myopathy.

A patient presented with myasthenic syndrome apparently not related to any neoplasia. A peculiar myopathy characterized by absolute predominance (99.50%) and atrophy of type 2A muscle fibers was found in both quadriceps muscles. It is difficult to determine the relation between the myasthenic syndrome and the localized quadriceps myopathy for which a congenital nature is suggested.

Adult↗
PubMed1979

Galactose metabolism in isolated perfused suckling-rat liver.

The metabolic conversion of 1, 2, or 4 mM galactose to glucose was studied in isolated livers of suckling rats. Whereas galactose uptake during perfusion with 1 and 2 mM galactose was linear throughout the 90-min experiment, uptake was delayed for 35 min when 4 mM galactose was perfused. Studies with radioactive galactose revealed a parallel disappearance of galactose and the appearance of [14C]glucose; about 80% of the galactose taken up was converted to glucose. Galactose perfusion appeared to reduce the basal amount of glucose derived from substrates other than galactose. The specific activities in the galactose-perfused livers of the three major galactose metabolizing enzymes, galactokinase, galactose-1-phosphate uridylyltransferase, and uridine diphosphogalactose-4-epimerase, revealed that the transferase was significantly lower, whereas that of galactokinase and epimerase were significantly higher than in livers perfused without galactose. No meaningful changes were observed in the levels of either phosphorylated or uridylated hexoses in these studies.

Animal Population Groups↗
PubMed1979

Hypokalemic periodic paralysis in primary hyperaldosteronism. Subclinical myopathy with atrophy of the type 2A muscle fibers.

A case of a patient suffering from primary hyperaldosteronism is reported. In this case the disease is manifested clinically by periodic paralysis and hypopotasemia without permanent myopathy. The morphological study of the muscle demonstrates selective atrophy of the type 2A fibers as the most pronounced alteration. These findings suggest a chronic myopathic process.

Aged↗
PubMed1978

Hereditary distal myopathy with onset in early infancy. Observation of a family.

The study of a family affected with hereditary distal myopathy with onset in early infancy is presented. Complete neurological examination was necessary in several members of the two last generations to discover the existence of the abnormalities of which they were unaware. The propositus was the most affected member of the family iwth distal paresis of the upper and lower extremities and selective paresis of the deltoid muscles. In addition he had kyphoscoliosis, talipes valgus and limitation of mobility of several joints. The onset of the disease was estimated as before the age of 2 when the child started walking. There was no progression of the disease. Clinical examination suggested a myopathic origin of the condition. A sural nerve biopsy was normal. Light-microscopy histochemical studies disclosed a predominance of type I fibres which were at the same time hypotrophic. Subsarcolemmal deposits of mitochondria were present although they were scanty and of normal ultrastructural appearance. In view of the morphological presentation it is postulated that this disease should be classified within the groups of myopathies accompanied by disproportion of fibres and selective atrophy of type I fibres.

Adult↗
PubMed1978

Myotonia in centronuclear myopathy.

Centronuclear myopathy, which is unusual because of clinical myotonia, is described in two sisters. The diagnosis was established in adult life, but the first symptoms were noticed in infancy. The outstanding points of the clinical picture were mild amyotrophy, paresis, and clinical myotonia.

Adenosine Triphosphatases↗
PubMedDate not supplied

Congenital insensitivity to pain with anhidrosis.

A nine-year-old child presented with congenital insensitivity to pain and anhidrosis. Quantitative studies and electron microscopy of the cutaneous branch of the radial nerve revealed almost complete absence of small myelinated and unmyelinated fibers and a disproportionate number of nerve fibers with a diameter of 6-10 micrometers. A grouping of both type 1 and type 2 muscle fibers was also seen. We suggest that this disease entity is not caused by a hereditary sensory neuropathy, but rather that it derives from a developmental defect.

Child↗
PubMedDate not supplied

First case of natural infection in pigs. Review of Trypanosoma cruzi reservoirs in Mexico.

An epidemiological research project was performed in the State of Morelos including collection of samples for blood smears and culture, serological tests, and xenodiagnoses from a total of 76 domestic and peridomestic mammals. Two strains of Trypanosoma cruzi were isolated by haemocultures; one from a pig (Sus scrofa), the first case of natural infection reported in Mexico, and the other from a dog (Canis familiaris). This study summarizes current information in Mexico concerning confirmed reservoirs of T. cruzi.

Animals↗