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Biomedical subjects

I Rubio

Publications and source records attributed to I Rubio.

40 records · Page 3Linked to original sources
PubMed1991

Ca(2+)-independent release of glutamate during in vitro anoxia in isolated nerve terminals.

The effects of in vitro anoxia on the release of glutamate in isolated nerve terminals were studied. The extra-synaptosomal concentration of glutamate ([Glu]ext) under aerobic conditions was 2.3 microM and increased to 4.9 microM after 10 min of anoxia. However, when synaptosomes were incubated in the presence of lactate plus pyruvate instead of glucose, to prevent anaerobic glycolysis, anoxia induced an eightfold increase in the [Glu]ext. The accumulation of glutamate in the external medium during anoxia was Ca2+ independent and insensitive to a significant reduction of the Ca(2+)-dependent release of the amino acid. These results indicate that a Ca(2+)-independent efflux of cytoplasmic glutamate occurs during in vitro anoxia in isolated nerve terminals.

4-Aminopyridine↗
PubMedDate not supplied

Alzheimer's disease, beta-amyloidosis, and aging.

Alzheimer's disease (AD) is rapidly moving from the obscure category of degenerative diseases to the more precise one of metabolic disorders. Recent discoveries have substantiated the hypothesis that AD results from the deposition of beta-amyloid, which is formed by polymers of a proteolytic fragment of the amyloid protein precursor (APP), and may induce intraneuronal aggregation of the microtubule-associated protein tau into paired helical filaments and neuronal death. There is also evidence that AD is a heterogeneous age-related disorder of multifactorial origin, which may arise as a consequence of point mutations of genes encoding APP or other proteins involved in its metabolism (familial AD), or a combination of genetic and non-genetic factors (sporadic AD). Familial AD displays genetic and phenotypic heterogeneity, meaning that mutations of different genes may cause the AD phenotype, and that different mutations of the same gene may cause phenotypically distinct disorders, including Alzheimer-type dementia and cerebral amyloid angiopathy with cerebral hemorrhages and stroke. On the other hand, aging, gender, head trauma, and variants of the apolipoprotein E gene have been shown to increase the risk of developing the more prevalent sporadic form of AD. The mechanisms by which these factors influence amyloidogenesis are beginning to be understood, and this will provide a rational basis for future therapy. Knowledge of the molecular basis of AD would eventually allow accurate risk prediction before the disease becomes clinically apparent, and better chances for early treatment and prevention.

Aging↗
PubMedDate not supplied

[Lymphatic cutaneous rickettsiosis caused by Rickettsia conorii in Uruguay].

Three autochthonous cases of cutaneous-ganglionar rickettsiosis transmitted by dogs ticks (Amblyomma maculatum in one of them) are reported. Two of the three cases were undoubtely produced by Rickettsia conorii according to the results of the specific indirect immunofluorescence technique IEF-IgM anti R. conorii. A third case is included due to the clinical epidemiological similarity, the positive serum reactivity with Proteus O x 19 and the rapid response to tetracycline. Autochthonous rickettsiosis by R. conorii has not been previously registered in the American area what confers special interest to this communication. The search of the disease in the other countries of the region is suggested.

Adolescent↗