Role of vitamin A metabolism in IIH: Results from the idiopathic intracranial hypertension treatment trial.

INTRODUCTION: Vitamin A and its metabolites (called retinoids) have been thought to play a role in the development of idiopathic intracranial hypertension (IIH). The IIH Treatment Trial (IIHTT) showed the efficacy of acetazolamide (ACZ) in improving visual field function, papilledema grade, quality of life and cerebrospinal fluid (CSF) pressure. We postulated that IIH patients would demonstrate elevated measures of vitamin A metabolites in the serum and CSF. METHODS: Comprehensive measures of serum vitamin A and its metabolites were obtained from 96 IIHTT subjects, randomly assigned to treatment with ACZ or placebo, and 25 controls with similar gender, age and body mass index (BMI). These included retinol, retinol binding protein, all-trans retinoic acid (ATRA), alpha- and beta-carotenes, and beta-cryptoxanthin. The IIHTT subjects also had CSF and serum vitamin A and metabolite measurements obtained at study entry and at six months. RESULTS: At study entry, of the vitamin A metabolites only serum ATRA was significantly different in IIHTT subjects (median 4.33nM) and controls (median 5.04nM, p=0.02). The BMI of IIHTT subjects showed mild significant negative correlations with serum ATRA, alpha- and beta-carotene, and beta-cryptoxanthin. In contrast, the control subject BMI correlated only with serum ATRA. At six months, the serum retinol, alpha-carotene, beta-carotene, and CSF retinol were increased from baseline in the ACZ treated group, but only increases in alpha-carotene (p=0.02) and CSF ATRA (p=0.04) were significantly greater in the ACZ group compared with the placebo group. No other vitamin A measures were significantly altered over the six months in either treatment group. Weight loss correlated with only with the change in serum beta-carotene (r=-0.44, p=0.006) and the change in CSF retinol (r=-0.61, p=0.02). CONCLUSION: Vitamin A toxicity is unlikely a contributory factor in the causation of IIH. Our findings differ from those of prior reports in part because of our use of more accurate quantitative methods and measuring vitamin A metabolites in both serum and CSF. ACZ may alter retinoid metabolism in IIH patients.

Distribution of protein kinase Mzeta and the complete protein kinase C isoform family in rat brain.

Protein kinase C (PKC) is a multigene family of at least ten isoforms, nine of which are expressed in brain (alpha, betaI, betaII, gamma, delta, straightepsilon, eta, zeta, iota/lambda). Our previous studies have shown that many of these PKCs participate in synaptic plasticity in the CA1 region of the hippocampus. Multiple isoforms are transiently activated in the induction phase of long-term potentiation (LTP). In contrast, a single species, zeta, is persistently activated during the maintenance phase of LTP through the formation of an independent, constitutively active catalytic domain, protein kinase Mzeta (PKMzeta). In this study, we used immunoblot and immunocytochemical techniques with isoform-specific antisera to examine the distribution of the complete family of PKC isozymes and PKMzeta in rat brain. Each form of PKC showed a widespread distribution in the brain with a distinct regional pattern of high and low levels of expression. PKMzeta, the predominant form of PKM in brain, had high levels in hippocampus, frontal and occipital cortex, striatum, and hypothalamus. In the hippocampus, each isoform was expressed in a characteristic pattern, with zeta prominent in the CA1 stratum radiatum. These results suggest that the compartmentalization of PKC isoforms in neurons may contribute to their function, with the location of PKMzeta prominent in areas notable for long-term synaptic plasticity.

[Treatment of tuberculosis in 100 children. A 5-year follow-up]. / Tratamiento de tuberculosis en 100 niños. Seguimiento durante cinco años.

This paper presents the results of a five year follow-up study of a cohort of children under fifteen years of age with tuberculosis. One group received standard treatment, and the other group received short course treatment. In the standard group there were four treatment failures, while in the other group, all the subjects had an excellent evolution and there were no failures. There was not a statistically significant difference regarding treatment failures, it is recommended, however, to carry out similar studies with greater sample sizes in order to determine the benefits of the short course treatment.

[Tuberculous meningitis: a 10-year analysis at the "Dr. Federico Gómez" Children's Hospital of Mexico]. / Meningitis tuberculosa: análisis de diez años en el Hospital Infantil de México "Dr. Federico Gómez".

Of all the forms of tuberculous infection in children, the most frequent is the pulmonary, but the tuberculous meningitis is the most severe and mortal, it occurs mainly in children under five years old, and the highest mortality is in children under two. The results of a retrospective study carried out at the Children Hospital of Mexico "Dr. Federico Gómez" about all the patients hospitalized with tuberculous meningitis diagnose during the January 1975 to December 1985 period were presented. One hundred and eighteen cases were studied: the majority (80%) corresponded to children under four years old, a percentage of 79 presented some degree of malnutrition, and 86 per cent showed clinical data of neurological affection. The confirmation of the diagnose was made in the majority of cases through laboratory and cabinet studies. Forty per cent showed no alteration in the chest X-rays, and the isolation of the bacillus was in a very low percentage (15%). All the patients were treated with the antituberculous drugs mentioned, with a better development in the ones associated with steroids. The hospital stay was over 30 days in 15 per cent of the cases. The mortality of the series reviewed was 44.5 per cent.