Dn. Orth

Bio: Dn. Orth is an academic researcher. The author has contributed to research in topics: Adrenal cortex. The author has an hindex of 1, co-authored 1 publications receiving 1152 citations.

The adrenal cortex.

Abstract: is "friction, obstruction and the defeat of most attempts at improved control". Sometimes the less pecunious neighbour, in its determinationto retain a valued rateable area, will bitterly resent and obstruct all attempts to transfer such portions of a town as lie within its own boundaries to the local authority controlling the major part of the urban area. Again, many of the roads boards covering extensive areas are but sparsely populated; in some instances great parts are quite uninhabited. In these instancesthe ratio of population to areamay be so low that even the highest possible rating will yield insufficient money for health purposes. The result has been that in theseareasthere has been a tendencyto use for 'road board administration money that has been collected as a health rate. This kind of arrangementcan only be describedas ridiculous. It is also pathetic. Dr. Cook states bluntly that education of the public in the principles of hygiene has been neglected. "This", he declares, "must be inevitable where the Local Authority is uninformed and where there is no technical adviser to impart the fundamentalsof knowledge by precept or by coercion." Government departments,he insists, set an example of tolerated neglect. Describing defects in the provision of privies, he states that conspicuous among thosewhich do not conform to local by-laws or to the first principles of sanitation are those of the Railway Commissioner, the Parks and Gardens Board, the Education Department,public hospitalsand local roads boardsthemselves. The astoundingstatementis madethat at 91 public schools the duty of night soil disposal is imposed upon the school teacheror the school children. At the outset the report issued by Dr. Cook was describedas a departmentaldirge. There are some bright spots in it, but the present need is to emphasize the unsatisfactorybasis on which much of the public health work has to be attempted. A year or two ago it was urged that a Royal Commissionshould be set up to survey the public health needs of Western Australia and to suggestways in which those needs could be met. This has not been done. If a commission is merely to take evidencewhich will be put on one side, as sooften happens, it would be better not to waste money on the effort. If the governmentwould consider the setting up of a new framework to replace the presentroads board patchwork, the step would be worth while. If nothing is done in the next few months perhaps some public spirited member of the medical profession will presentat the congressin Perth next August a pap"erwhich can be usedas a weapon to arousepublic interestand indignation.

How do glucocorticoids influence stress responses? Integrating permissive, suppressive, stimulatory, and preparative actions.

Abstract: The secretion of glucocorticoids (GCs) is a classic endocrine response to stress. Despite that, it remains controversial as to what purpose GCs serve at such times. One view, stretching back to the time of Hans Selye, posits that GCs help mediate the ongoing or pending stress response, either via basal levels of GCs permitting other facets of the stress response to emerge efficaciously, and/or by stress levels of GCs actively stimulating the stress response. In contrast, a revisionist viewpoint posits that GCs suppress the stress response, preventing it from being pathologically overactivated. In this review, we consider recent findings regarding GC action and, based on them, generate criteria for determining whether a particular GC action permits, stimulates, or suppresses an ongoing stressresponse or, as an additional category, is preparative for a subsequent stressor. We apply these GC actions to the realms of cardiovascular function, fluid volume and hemorrhage, immunity and inflammation, metabolism, neurobiology, and reproductive physiology. We find that GC actions fall into markedly different categories, depending on the physiological endpoint in question, with evidence for mediating effects in some cases, and suppressive or preparative in others. We then attempt to assimilate these heterogeneous GC actions into a physiological whole. (Endocrine Reviews 21: 55‐ 89, 2000)

Maternal care, gene expression, and the transmission of individual differences in stress reactivity across generations.

Abstract: Naturally occurring variations in maternal care alter the expression of genes that regulate behavioral and endocrine responses to stress, as well as hippocampal synaptic development. These effects form the basis for the development of stable, individual differences in stress reactivity and certain forms of cognition. Maternal care also influences the maternal behavior of female offspring, an effect that appears to be related to oxytocin receptor gene expression, and which forms the basis for the intergenerational transmission of individual differences in stress reactivity. Patterns of maternal care that increase stress reactivity in offspring are enhanced by stressors imposed on the mother. These findings provide evidence for the importance of parental care as a mediator of the effects of environmental adversity on neural development.

Disruption of the glucocorticoid receptor gene in the nervous system results in reduced anxiety

Abstract: The glucocorticoid receptor (Gr, encoded by the gene Grl1) controls transcription of target genes both directly by interaction with DNA regulatory elements and indirectly by cross-talk with other transcription factors. In response to various stimuli, including stress, glucocorticoids coordinate metabolic, endocrine, immune and nervous system responses and ensure an adequate profile of transcription. In the brain, Gr has been proposed to modulate emotional behaviour, cognitive functions and addictive states. Previously, these aspects were not studied in the absence of functional Gr because inactivation of Grl1 in mice causes lethality at birth (F.T., C.K. and G.S., unpublished data). Therefore, we generated tissue-specific mutations of this gene using the Cre/loxP -recombination system. This allowed us to generate viable adult mice with loss of Gr function in selected tissues. Loss of Gr function in the nervous system impairs hypothalamus-pituitary-adrenal (HPA)-axis regulation, resulting in increased glucocorticoid (GC) levels that lead to symptoms reminiscent of those observed in Cushing syndrome. Conditional mutagenesis of Gr in the nervous system provides genetic evidence for the importance of Gr signalling in emotional behaviour because mutant animals show an impaired behavioural response to stress and display reduced anxiety.