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H Ferreyra

Publications and source records attributed to H Ferreyra.

8 recordsLinked to original sources
PubMed2002

Production of Aspergillus terreus alpha-L-rhamnosidase by solid state fermentation.

AIMS: The study of production of Aspergillus terreus CECT 2663 alpha-L-rhamnosidase in solid state fermentation using wheat bran, washed sugar cane bagasse and polyurethane foam as substrates or supports for the enzyme production. METHODS AND RESULTS: Cultures were carried out in Petri dishes under controlled temperature and humidity. Naringin or rhamnose were the enzyme inducers and carbon sources. The enzyme activity to inducer ratio was appreciably greater when using sugar cane bagasse or polyurethane foam than wheat bran. The influence of inoculum size, inducer, airflow, humidity and temperature were determined. Under optimum conditions, about four units of enzyme per ml nutrient solution were obtained after 4-6 d. CONCLUSIONS: The activity to inducer ratio was higher, and the cultivation time was shorter in solid state fermentation than those observed in submerged cultures. SIGNIFICANCE AND IMPACT OF THE STUDY: Solid cultures, using naringin as inducer, can be appropriate alpha-L-rhamnosidase production.

Aspergillus↗
PubMed2000

Does tongue size differ between patients with and without sleep-disordered breathing?

OBJECTIVES/HYPOTHESIS: To determine whether there is a difference in the tongue size of patients with and without sleep-disordered breathing (SDB) and to evaluate whether tongue volume correlates with body mass index (BMI), neck circumference, age, Epworth Sleepiness Scale score, or apnea-hypopnea index (AHI). STUDY DESIGN: Nineteen patients (9 with SDB; 10 without SDB) were enrolled in this prospective study. METHODS: All patients completed a sleep questionnaire including the Epworth Sleepiness Scale and underwent a physical examination, portable sleep study, and magnetic resonance imaging (MRI) study. An examiner masked to the patients' disease status measured tongue volume from the MRI films. RESULTS: There was a trend for patients with SDB to have a larger tongue volume than patients without SDB (P = .065). Tongue volume only positively correlated with BMI (P = .005) and neck circumference (P = .013), but there was no correlation with age (P = .23) or AHI (P = .40). CONCLUSIONS: There is a statistical trend for patients with SDB to have larger tongue size compared with non-SDB patients, but tongue size is independent of AHI and correlates significantly with BMI and neck circumference. We interpret these findings to suggest that variations in tongue size alone cannot account for disease severity and may simply reflect the larger body habitus often seen in patients with SDB.

Adult↗
PubMed1983

Influences of the limbic system on hypothalamo-neurohypophysial system.

(1) Effects of stimulations of various limbic structures (the olfactory bulb, olfactory tubercle, prepyriform cortex, endopyriform nucleus and various parts of amygdaloid nuclei) on the neurosecretory neurons in the supraoptic (SON) and paraventricular nuclei (PVN) of the hypothalamus were studied. All regions stimulated received strong inputs from the olfactory bulb. (2) Out of 195 "identified' neurosecretory neurons tested one-half or more (49-74%, depending on the structures stimulated) were inhibited by stimuli consisting of 1-3 short pulses. The inhibition occurred immediately after the stimulus in approximately one-fifty of all inhibited neurons, in the remaining four-fifths inhibition occurred after more than 20 ms latency. Inhibition of neurosecretory neuron activity lasted for several hundred milliseconds, often followed by clear post-inhibitory excitation or rebound. (3) In 23 neurons, a distinct "evoked' response of brief duration occurred with a 30 ms latency following stimulation of the lateral and medical amygdala, olfactory tubercle and prepyriform cortex. In another 17 neurons, a general increase in background activity with a longer latency (50-100 ms) occurred following stimulation of nearly all amygdaloid nuclei, olfactory tubercle and the pyriform cortex: lateral amygdala stimulation caused an excitation of the largest proportion of neurosecretory cells (30%) while none was excited by stimulation of the olfactory bulb and endopyriform cortex, except those occurring as post-inhibitory excitation. (4) There was a convergence of afferent impulses on single neurosecretory cells. A large proportion (42%) of the neurons received inputs from 2 to 4 limbic regions. (5) Neurosecretory cells which were influenced by limbic stimuli were also inhibited by baroreceptor activation and excited by osmotic stimulation. "Unidentified' neurons within SON and PVN and "atypical neurosecretory cells' (those responding to pituitary stalk stimulation with varying latencies) were also affected by the forebrain stimulation; some of these were also affected by an osmotic stimulus. A part of this group may send their axons to the median eminence.

Action Potentials↗