Publications by authors named "Alvarez X"

The influence of brain histamine (HA) on learning and memory is not well understood, although some reports indicate that HA improves memory consolidation. We have studied the effects of alpha-fluoromethylhistidine (FMH) (100 mg/Kg, i.p.

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Recent studies seem to indicate that the somatotropinergic system (STS) (GRF-SS-GH-SM axis) may be involved in the neuromodulation of higher activities of the central nervous system (CNS). In an attempt to demonstrate the influence of the STS on memory functions in humans, we have investigated the effects of acute administration of exogenous GRF vs. placebo on short-term memory (STM) in healthy young subjects.

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In order to investigate the potential antagonistic actions of the two main neuroregulators of the somatotropinergic system (GRF-SS-GH-SM axis), growth hormone-releasing factor (GRF) and somatostatin (SS) at the central level, the effects of GRF and SS on locomotor activity (LA) were studied in a computerized system. Male Wistar rats (N = 6-9 per group) received i.p.

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Ethionine-resistant mutants of Candida utilis CCY-158 overproducing methionine have been isolated. In these mutants the intracellular methionine concentration decreased significantly during the stationary phase. The wild-type strain CCY-158 and the ethionine-resistant mutants isolated were able to use methionine as the nitrogen source but not as the carbon source.

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Three mannose-negative mutants of Saccharomyces cerevisiae have been isolated. These mutants showed growth inhibition when mannose was added to a growth medium containing glycerol or fructose. Crosses between wild type mutants showed segregation of 2+/2-.

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