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Biomedical subjects

J M Murphy

Publications and source records attributed to J M Murphy.

At least 235 records · Page 13Linked to original sources
PubMed1976

Development of cholinergic inhibitory capacities in the hyperthyroid mouse.

The ontogeny of behavioral arousal and inhibition, as measured by spontaneous locomotor activity, was compared in four experiments for controls and mice injected with thyroxine as neonates. Mice treated with thyroxine at 1-3 days of age had higher activity levels at 10-15 days of age than controls, suggesting potentiation of arousal systems by the hormone treatment. Although thyroxine-accelerated development had no reliable effect upon the age at which peak activity occurred, scopolamine injections increased activity as early as 15 days of age in thyroxine-treated mice, whereas saline-treated or unhandled controls did not show a similar increase until 16-17 days of age. The findings were interpreted as indicating both a potentiation of arousal and a compensatory acceleration of cholinergic inhibitory capacities as a result of the neonatal hyperthyroidism. In addition, the importance of the behaviorally suppressive effects of a novel injection experience in the neonatal mouse was demonstrated.

Aging↗
PubMed1976

Neonatal thyroxine stimulation accelerates the maturation of both locomotor and memory processes in mice.

In two experiments mice were injected with thyroxine on Postnatal Days 1, 2, and 3, and the subsequent effects upon the development of the swimming reflex and the emergence of instrumental learning/memory processes were examined. In agreement with past studies, early thyroxine treatment accelerated the maturation of swimming capacities and general physical development compared with littermate controls receiving saline injections. In the second study, thyroxine- and saline-treated mice received 25 training trials on a shock-escape T-maze taks at 7, 9, 11, or 13 days of age with a retention test 24 hr later. The results indicated that while learning was equivalent within each of the ages between the treatment groups, onset of 24-hr retention capacity occurred approximately 2 days earlier in the thyroxine-treated mice than in controls. In addition, a performance deficit was observed in the thyroxine mice at the oldest age tested, in agreement with previous reports. The results of these experiments suggest that early hyperthyroidism results in earlier maturation of both locomotor and memory processes, followed by later performance deficits.

Age Factors↗
PubMed1976

Corn grain preserved with ammonium isobutyrate for lactating dairy cattle.

Twenty-four lactating cows were fed one of three complete rations containing dry corn, ensiled corn, or corn treated with ammonium isobutyrate in a Latin square arrangement of treatments. Two weeks were used for adjustments to rations and 3 wk for collection of data. There were no differences in average daily yield of milk or fat-corrected milk, but fat percentage of milk from cows fed ensiled corn was lower than that of those given dry corn. Fat test of cows fed treated corn was intermediate and not different from the other groups. Molar proportions of volatile fatty acids and concentrations of rumen ammonia were not different among treatments.

Ammonia↗
PubMedDate not supplied

Loss in childhood: anxiety in adulthood.

Recent research, especially in Great Britain, has attracted interest by reporting on the relationship between maternal loss and vulnerability to depression among women. Several studies in the United States that included men have not received equal attention. The present study expands on the US work by reporting findings from the Queensbrook Study in New York City, a cross-sectional survey that provides information about the relationships between the family environment of childhood and the prevalence of psychiatric illness in adulthood. The Queensbrook survey was conducted in the mid 1960 as an urban counterpart to the Stirling County Study in rural Atlantic Canada. The data from the urban sample described here were not published earlier, and for this report we used DSM-111 criteria to develop scoring algorithme to identify depression and anxiety. We investigated several types of adverse childhood losses, not solely the death of a mother, and related them to depression and anxiety in both men and women. None of the childhood experience was significant associated with these disorders among women, nor was the death of a parent related to either type of disorder among men. However, boys who left home before 16 years of age, whose parents were divorced or separated, or who were placed in an adopted family had a threefold increase in rates of anxiety as adults. This finding of a positive association between the divorce of parents and later anxiety in men is supported by several of the other population surveys carried out in the United States.

Adjustment Disorders↗
PubMedDate not supplied

Protecting seriously mistreated children: time delays in a court sample.

The study examined the progress through the child protective system of a sample of 206 severely abused and/or neglected children brought before the Boston Juvenile Court (BJC) on Care and Protection (C & P) petitions. Overall, children were in the system an average of 5 years from the filing of the first official report of mistreatment to the resolution of their cases. The families had been known to the state child protective service agency for an average of more than 2.5 years before the current court involvement. Once arraigned in juvenile court on the C & P, the average case took almost 1.5 years to reach a disposition. After disposition, children permanently removed from parental custody required, on average, an additional year and a half in Probate Court to reach a permanent placement. Of the more than twenty variables examined, including severity of mistreatment, protective service history, and parental mental illness, no meaningful pattern emerged which could predict delays. Our findings characterize the delays experienced by many abused and neglected children, and highlight the necessity of closer monitoring of the progress of cases through the protective and court systems.

Adoption↗
PubMedDate not supplied

What happens after the care and protection petition? Reabuse in a court sample.

Of 206 cases of serious child mistreatment brought before a metropolitan juvenile court on Care and Protection Petitions (C & P), 63 (31%) were dismissed (returning the child to the parent(s]. During a 2-year follow-up period, 18 (29%) of these dismissed cases had substantiated reports of further mistreatment, and 10 (16%) subsequently returned to court on another C & P. Families that had previously been to court for a C & P, and those in which the parent was diagnosed psychotic or character disordered, were significantly more likely to return to court. In addition, we were surprised to find that 8 (6%) of the 130 children ordered permanently removed from parental custody also returned to court. This study documents the continuing mistreatment of children, even after the state's most serious interventions. The study also highlights the necessity of incorporating clinical research in the form of ongoing follow-up of individual cases into the court process, and suggests that it may be possible to identify cases with a very high probability of reinjury and return to court.

Adolescent↗
PubMedDate not supplied

Monoamine uptake inhibitors attenuate ethanol intake in alcohol-preferring (P) rats.

The P line of alcohol-preferring rats drink pharmacologically significant amounts of ethanol when given free choice between a 10 percent ethanol solution and water. Serotonin (5-HT) uptake inhibitors and desipramine, a norepinephrine (NE) uptake inhibitor, were found to significantly reduce their ethanol consumption for up to 24 hours after intraperitoneal injection. To determine if this effect of 5-HT uptake inhibitors could be altered by receptor antagonists, some of which are short acting, P rats were trained to drink ethanol by free choice during scheduled availability, with ethanol being presented one hour every four hours during the light cycle. The majority of the ethanol was consumed during the first hour of availability, and the ethanol intake was significantly reduced by the 5-HT uptake inhibitors, fluoxetine and fluvoxamine. Pretreatment with antagonists for 5-HT1, 5-HT2 and alpha- and beta-NE receptor systems failed to alter the fluvoxamine attenuation of ethanol intake. The mechanism by which 5-HT uptake inhibitors alter ethanol preference remains unclear.

Alcohol Drinking↗
PubMedDate not supplied

Effects of scheduled access on ethanol intake by the alcohol-preferring (P) line of rats.

The effects of scheduling the availability of ethanol on its voluntary consumption by the selectively bred alcohol-preferring P rats were examined under three conditions: unrestricted 24 hr/day access (Condition A), access limited to a continuous 4 hr/day (Condition B), and access limited to 1 hr every 3 hr, 4 times/day (Condition C). Food and water were always available. Daily alcohol intakes (mean +/- SEM) with Conditions A, B and C were 6.9 +/- 0.2, 2.1 +/- 0.2 and 4.4 +/- 0.2 g/kg, respectively, while the intake per hour of availability increased from 0.3 +/- 0.03 under Condition A to 1.1 +/- 0.4 g/kg under condition C. The amount of ethanol consumed per drinking episode under Conditions A, B and C were 1.1 +/- 0.1, 2.1 +/- 0.2 and 1.1 +/- 0.03 g/kg, respectively. Mean blood alcohol concentrations (BACs), determined periodically during the dark cycle of Condition A and five minutes after drinking episodes under Conditions B and C, were 59 +/- 10, 61 +/- 7 and 62 +/- 7 mg%, respectively. When unlimited access was reinstated after Condition C, daily alcohol consumption returned to a level similar to that under the initial Condition A (7.2 +/- 0.5 g/kg). When the ethanol concentration was increased from 5 to 20% (v/v) under Condition C, the amount of ethanol consumed per episode at 5% was significantly less than at the 10, 15 and 20% concentrations, and the volume consumed was significantly lower at the 20% concentration than at the 5, 10 and 15% concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol Drinking↗
PubMedDate not supplied

Effects of fluoxetine on the intragastric self-administration of ethanol in the alcohol preferring P line of rats.

Rats of the alcohol-preferring P line (n = 7) were trained to self-administer ethanol (20% v/v) and water via an intragastric IG catheter. Food was available ad lib. Ethanol intakes averaged approximately 5-6 g/kg body wt./day. Treatment with the serotonin (5-HT) uptake inhibitor fluoxetine (10 mg/kg/day; IG) for seven consecutive days produced a marked decrease in ethanol self-administration on the first day, which was sustained throughout the seven days of treatment to values as low as 1 g/kg/day. Concomitant with the decrease in ethanol intake, the self-infusion of water gradually increased during the period of fluoxetine treatment. Total caloric intake (ethanol plus food) was moderately reduced during fluoxetine treatment; the decrease in food consumption was consistent but not statistically significant. When fluoxetine treatment was terminated, ethanol self-administration quickly returned to the prefluoxetine levels, while water intake began to decrease. Since no ethanol was consumed orally, the IG ethanol was not self-administered for its taste or smell, but apparently for its postingestive pharmacological effects. The robust reduction of ethanol self-infusion that occurred with fluoxetine treatment suggests that the 5-HT systems are involved in the reinforcing effects of ethanol in the P line of rats.

Alcohol Drinking↗