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Biomedical subjects

I L Bernstein

Publications and source records attributed to I L Bernstein.

258 records · Page 15Linked to original sources
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Neonatal chorda tympani transection permanently disrupts fungiform taste bud and papilla structure in the rat.

The present report examined the morphology of fungiform papillae in adult rats that received bilateral chorda tympani transection at 10 days of age. Tongue tissue was examined using surface-structure analysis. Counts were made of fungiform papillae with a pore, fungiform papillae with no pore and fungiform papillae with a keratinized conical surface; a feature referred to as "filiform-like. " Neonatal chorda tympani nerve transection resulted not only in a loss of taste buds but also in a permanent loss in numbers of fungiform papillae. Compared with an average of 152 fungiform papillae in sham-operated control rats, there was an average of only 54 fungiform papillae after neonatal chorda tympani transection. Nearly 80% of these fungiform papillae in neonatal chorda tympani transected rats were filiform-like. No filiform-like papillae were noted in sham-operated rats. These results suggest that the chorda tympani nerve is necessary during an early postnatal period of development to maintain normal fungiform papillae morphology.

Animals↗
PubMedDate not supplied

Acute airway narrowing in monkeys from challenge with 2.5 ppm formaldehyde generated from formalin.

Nine adult male Cynomolgus monkeys (Macaca fascicularis) were exposed for 10 min to 2.55 +/- 0.03 ppm formaldehyde (HCHO; mean +/- standard error of the mean, SEM) generated from formalin with a newly developed HCHO challenge system. The generation system was capable of producing highly stable HCHO vapor concentrations with fluctuations of HCHO concentrations of less than +/- 5%. The experimental design included pre-exposure methacholine challenge to determine if responses to HCHO were associated with pre-existing bronchial hyperreactivity. Significant changes in average pulmonary flow resistance (RL) were observed (compared to control RL values) at 2 (p less than 0.01), 5 (p less than 0.01), and 10 min (p less than 0.005) post-HCHO challenge. Pre-challenge RL values (mean +/- SEM) were 11.3 +/- 1.4 cm H2O.l/s, while at 2, 5, and 10 min after HCHO challenge, values were 16.1 +/- 2.1, 16.9 +/- 2.8 and 20.0 +/- 3.4 cm H2O.l/s, respectively. Methacholine challenge data suggest that reactions to HCHO tend to be greater in monkeys hyperreactive to methacholine, but the relationship does not reach statistical significance in this small series of animals. These data indicate that significant pulmonary function deficits occur immediately after challenge with 2.55 ppm HCHO vapor in monkeys.

Administration, Inhalation↗
PubMedDate not supplied

A comparative tolerance study of terfenadine-pseudoephedrine combination tablets and pseudoephedrine tablets in patients with allergic or vasomotor rhinitis.

In this multicentre, double-blind, randomized, parallel group study, 315 patients with allergic or vasomotor rhinitis were treated on a twice daily dosing schedule with either a 60 mg terfenadine-120 mg pseudoephedrine hydrochloride combination or 120 mg pseudoephedrine hydrochloride (extended release) for 2 weeks. No clinically significant differences between the two groups were noted in body weight, temperature, respiration rate or blood pressure following the treatment period. An increase in mean heart rate of approximately 5 beats/min from entry to the final clinic visit was noted in both treatment groups. No clinically significant changes were noted in either treatment group when pre- and post-treatment electrocardiograms were compared. There were also no clinically significant alterations in laboratory values, which included serum chemistry, haematology and urinalysis, within or between either group. The adverse events profiles for both groups were similar. The most frequent adverse event was insomnia, in 40 (25.3%) patients given the terfenadine-pseudoephedrine combination and in 42 (26.8%) of those given pseudoephedrine. No unusual or unexpected adverse events were reported.

Adult↗
PubMedDate not supplied

Conditioning method dramatically alters the role of amygdala in taste aversion learning.

Although an important role for the amygdala in taste aversion learning has been suggested by work in a number of laboratories, results have been inconsistent and interpretations varied. The present series of studies reevaluated the role of the amygdala in taste aversion learning by examining the extent to which conditioning methods, testing methods and lesioning methods, influence whether amygdala lesions dramatically affect conditioned taste aversion (CTA) learning. Results indicated that when animals are conditioned with an intraoral (I/O) taste presentation, lesions of amygdala eliminate evidence of conditioning whether animals are tested intraorally or with a two-bottle solution presentation. Dramatic effects of amygdala lesions on CTA learning were seen whether lesions were made electrolytically or using an excitotoxin. In contrast, when animals were conditioned using bottle presentation of the taste, electrolytic lesions attenuated CTAs but did not eliminate them, and excitotoxic lesions had no effect. These results are consistent with the hypothesis that neural structures critical for CTA learning may differ depending on the extent to which the method of conditioned stimulus delivery incorporates a response component.

Amygdala↗