Biomedical subjects

G M Goodwin

Publications and source records attributed to G M Goodwin.

168 records · Page 10Linked to original sources

PubMedDate not supplied

Dieting and weight loss in volunteers increases the number of alpha 2-adrenoceptors and 5-HT receptors on blood platelets without effect on [3H]imipramine binding.

Platelet monoamine receptor binding was determined in normal male and female subjects before and at the end of a 2- to 3-week weight reducing diet (1200 kcal daily). Dieting was associated with an increase in platelet binding sites for both [3H]yohimbine and [125I]iodolysergic acid diethylamide (iodoLSD). The affinity at the platelet [125I]iodoLSD binding site was reduced. In contrast, [3H]imipramine binding was unchanged. These results have important implications for studies that employ platelet binding as a peripheral marker of neurotransmitter function in psychiatric illness.

Adult↗

PubMedDate not supplied

The effects of dieting and weight loss upon the stimulation of thyrotropin (TSH) by thyrotropin-releasing hormone (TRH) and suppression of cortisol secretion by dexamethasone in men and women.

The effects upon basal hormone levels and neuroendocrine responses of a weight reducing diet allowing 1200 kcal daily were determined in male and female volunteers. Thyrotropin (TSH) responses to thyrotropin-releasing hormone (TRH) were unchanged in men but attenuated in women; this effect was associated with a fall in basal TSH in women, not in men. Rates of non-suppression of cortisol in response to oral dexamethasone (1 mg) were unchanged during dieting although basal morning cortisol levels rose in males and females. The implications for the use of the TRH test and the dexamethasone suppression test (DST) in depressive illness are discussed.

Adult↗

PubMedDate not supplied

Lymphocyte glucocorticoid receptor binding in depression: normal values following recovery.

The number of glucocorticoid receptor sites in lymphocytes and plasma cortisol concentrations were measured in 20 patients who had recovered from major depressive disorder and 20 healthy control subjects. The number of glucocorticoid receptor sites in lymphocytes from the recovered depressed group was not significantly different from that of the control group. Although the mean plasma cortisol concentration in recovered depressives was higher than in control subjects, the difference only just reached significance. This study shows that the reduction in glucocorticoid receptor numbers which occurs during acute depressive illness does not persist on recovery and is, therefore, state-dependent.

Adult↗

PubMedDate not supplied

Association of short alleles of a VNTR of the serotonin transporter gene with anxiety symptoms in patients presenting after deliberate self harm.

The polymorphism of a variable number tandem repeat (VNTR) region of the serotonin transporter gene consists of three alleles containing, respectively, 9 (STin2.9), 10 (STin2.10) and 12 (STin2.12) copies of a repetitive element. The frequencies of the three alleles in 384 individuals presenting after deliberate self harm were the same as a group of 346 controls. However, ratings of anxiety (and state anger) were higher in those patients with genotypes including the shorter repetitive elements. The findings support the hypothesis that, in this group of patients with low rates of severe psychiatric disorder, allelic variation in the serotonin transporter gene may contribute to the expression of anxiety symptoms.

Aggression↗

PubMedDate not supplied

Presynaptic serotonin receptor-mediated response in mice attenuated by antidepressant drugs and electroconvulsive shock.

Ligand-binding studies have demonstrated two types of serotonin (5-HT) receptor, 5-HT1 and 5-HT2, in the brains of rodents and there is additional evidence for the existence of 5-HT1 subtypes. Recently a new drug, 8-hydroxy-2-(di-N-propylamino)tetralin (8-OH-DPAT), has been identified which shows high selectivity for binding to 5-HT1 (possibly 5-HT1A) receptors and which binds to presynaptic serotonin autoreceptors in some regions of rat brain. We have shown previously, that this compound produces a hypothermic response in mice, probably via an agonist action at serotonin presynaptic receptors. Here we show that a wide range of antidepressant treatments decrease the hypothermic response to 8-OH-DPAT over a time course comparable to the onset of therapeutic action. Interestingly, repeated electroconvulsive shock (ECS) has the same effect. We propose that this change is relevant to the mechanism of action of antidepressant drugs.

8-Hydroxy-2-(di-n-propylamino)tetralin↗

PubMedDate not supplied

Exposures from thorium contained in thoriated tungsten welding electrodes.

Information provided in this article can be used for estimating the radiation dose associated with the use of thoriated tungsten electrodes in tungsten inert gas welding. Area and breathing zone concentrations of 232Th generated by welding and electrode sharpening along with particle size information; isotopic composition of electrodes from two domestic manufacturers and one European manufacturer; and process variables and estimates on the number of thoriated tungsten electrodes manufactured are presented. Past literature is reviewed and compared with the results of this study. Isotopic analysis of a nominal 2% thoriated electrode found 0.6 ppm +/- 0.4 ppm 230Th and less than 0.1 ppm 228Th. Analysis of a ceriated tungsten electrode and a lanthanated tungsten electrode for 232Th found 124 ppm and 177 ppm, respectively. Electrode consumption during welding was primarily the result of tip sharpening. Less than 3% of the weight loss was attributable to the welding process. The in-mask concentration of respirable thorium particulate in the welder's breathing zone was 0.002 x 10(-12) microCi 232Th/mL. The concentration of respirable thorium particulate from electrode sharpening was 1.3 x 10(-12) microCi 232Th/mL. The measured sharpening time was 20 sec per electrode. Estimates of the activity median aerodynamic diameters for the respirable fraction of the welding and electrode sharpening aerosols were 3.5 and 5 microns, respectively, when measured in the breathing zone at 0.3 m (12 inches) from the point of operation. The respirable fraction of the total welding and sharpening aerosols was 45 and 60%.

Air Pollutants, Occupational↗