Biomedical subjects

S Barron

Publications and source records attributed to S Barron.

59 records · Page 4Linked to original sources

PubMedDate not supplied

Pup-induced maternal behavior in adult and juvenile rats exposed to alcohol prenatally.

The effects of prenatal alcohol exposure on pup-induced maternal behaviors were examined in virgin rats whose mothers consumed liquid diets containing either 35 or 0% ethanol-derived-calories (EDC) on days 6-20 of gestation. A pair-feeding procedure was utilized to control for reduced caloric intake and, in addition, an ad libitum lab chow group was included to control for possible liquid diet effects. The results from experiments 1 and 2 revealed a sexually differential effect on this behavior in adult virgins exposed to alcohol in utero. Adult 35% EDC females showed a variety of deficits in maternal behaviors relative to controls; however, males with similar prenatal treatment appeared unaffected. In experiment 3, both 35% EDC male and female juveniles displayed altered maternal behaviors relative to controls. These results demonstrate yet another behavior sensitive to prenatal alcohol exposure. Prenatal hormonal alterations occurring as a consequence of maternal alcohol consumption may be a mechanism by which this long term behavioral effect is observed. This hypothesis and the importance of future research in this relatively new area of fetal alcohol studies are discussed.

Animals↗

PubMedDate not supplied

The effects of physostigmine on open-field behavior in rats exposed to alcohol prenatally.

The present study examined the effects of physostigmine, a cholinesterase inhibitor, on activity in young rats whose mothers consumed isocaloric liquid diets containing 35% or 0% ethanol-derived calories on days 6-20 of pregnancy. A pair-feeding procedure was utilized and an ad libitum lab chow group was included. Physostigmine was administered to 18-day-old offspring on 3 consecutive days with activity measures recorded for 30 min each day. Injections of physostigmine produced significant reductions in activity in alcohol-exposed offspring relative to control groups. These results provide support for a functional cholinergic deficit in offspring exposed to alcohol in utero and may have relevant clinical implications in the treatment of attentional deficit disorder which can occur following prenatal alcohol exposure.

Animals↗

PubMedDate not supplied

Power spectral analysis of heart rate variability during upright tilt test: a comparison of patients with syncope and normal subjects.

We analyzed heart variability (HRV) response to tilt in 35 patients with a history of neurocardiogenic syncope and in 8 normal volunteers. Frequency domain examination was performed using power spectral analysis of RR variability during resting supine position and during the 256 beats preceding the onset of syncope or completion of 60 min of upright tilt to 70 degrees. Both low (0.05-0.15 Hz) and high frequency (0.15-0.4 Hz) spectral components of HRV increased markedly in all groups as a result of tilting. Statistically significant differences were noted between the patient groups at completion of upright tilting. However, these differences in spectral components between groups were of small magnitude when compared to the overall increase in spectral power occurring in all groups as a result of the tilt and are difficult to correlate clinically with the appearance, or lack of appearance of tilt-induced syncope. Power spectral analysis of HRV, as presently performed, appears to lack discriminative power to detect the rapid and marked changes in sympathovagal modulation known to occur during tilt test in patients with neurocardiogenic syncope.

Adolescent↗

PubMedDate not supplied

Health effects from exposure to organophosphate pesticides in workers and residents in Israel.

Major findings from our work on exposures and effects from organophosphate-containing pesticides in selected occupational and community patients and groups in Israel are reviewed as a basis for recommending control measures. The worker groups were pilots, ground-crews, and field workers; exposed nonworkers were adults and children living in kibbutzim with drift exposures, and household residents in houses treated by pest exterminators. In all groups, evidence of exposure-illness associations was found even though persons with acute poisoning were not seen. Complaints (headache, dizziness, fatigue, nausea, breathing problems, abdominal cramps, and tingling in extremities) were associated with within-normal depressions in cholinesterase activity. Whole blood and plasma cholinesterase activity were slightly more sensitive indicators of mixed exposure than red blood cell cholinesterase activity. High alkyl phosphate levels and symptoms were seen in individuals with within-normal limit depressions in cholinesterase activity. Complaints of weakness and tingling in hands and feet, together with low-grade changes in nerve conduction, suggest the possible influence of agents with a neurotoxic esterase-type activity independent of cholinesterase activity. Transient in-season neuropsychological changes in tests of mood status and performance were associated with exposure. Recommendations for exposure reduction include: accelerating the already declining use of pesticides in general, and organophosphates in particular; promoting the shift from more to less toxic organophosphates and other pesticides; and introducing rigid performance specifications for closed systems in loading and mixing at end-user sites. Dermal protection remains a problem. Cholinesterase activity levels and symptom interviews are useful for monitoring workers at risk, but alkyl phosphate levels are the definitive measure of exposure, surveys, investigations and surveillance.

Adolescent↗

PubMedDate not supplied

The effect of chronic lead intoxication in mature chickens.

In a study of chronic lead intoxication in mature chickens, blood lead levels were significantly lower in hens than in roosters receiving the same oral dose of lead. It was then shown that eggshells from lead-treated hens contained 6-12 times the lead concentration of eggshells from control hens. Similarly, the lead content of egg yolks from treated hens was significantly higher than yolks from controls. Lead-treated hens laid significantly more eggs during the period of observation of nearly 3 years because of the increased frequency of laying cycles, which was almost three times that of control hens. A further observation was histologic damage to the mature testes of the rooster.

Age Factors↗