Biomedical subjects
Publications and source records attributed to R L Reid.
In an examination of arginine-utilizing Mycoplasma species, simple fluorogenic and chromogenic tests were used to demonstrate high levels of arginine aminopeptidase activity in unwashed, unconcentrated broth and agar cultures in all strains of 5 species and low levels of activity in all strains of 14 species. Four species contained strains which exhibited either high or low levels of activity.
Explore the source record for details and available documents.
The efficacy, safety, and patient's acceptance of intravenous and subcutaneous therapy with gonadotropin releasing hormone (GnRH) with the use of either an autoinfusion pump or a smaller manual pen pump delivery system have been evaluated during the induction of ovulation in outpatients with hypothalamic hypogonadotropic amenorrhea. An ovulatory response to intravenous GnRH was highly reproducible, even at low doses, and complications associated with the intravenous route of delivery were infrequent and readily treated. Although no complications were observed during subcutaneous GnRH therapy, the response to the subcutaneous route of delivery was unpredictable over a wide range of dosages and delivery schedules. The pen pump was rated more highly by subjects than the autoinfusion pump, because the pen pump was both light and inconspicuous.
Some variations in animal health among geographic areas are associated with variations in soils, water supplies or soil parent materials. Geochemical bases for health problems arising from essential nutrient element deficiencies or from toxic levels or imbalances of several elements are widely recognized. Less attention has been directed to the possibilities of geochemical influences upon regional differences in health resulting from pathogens, parasites, mycotoxins and poisonous plants. This review is an effort to collect and interpret such evidence as has been published on the subject since Louis Pasteur's original observation associating soil character and probability of anthrax.
Administration of human beta-endorphin (2.5 mg IV bolus) to three subjects with non-insulin-dependent diabetes mellitus (type II) induced prompt and simultaneous increments in the plasma concentrations of insulin and glucagon lasting up to 90 minutes. In contrast to the hyperglycemic response previously observed in normal subjects following beta-endorphin, these diabetics showed a progressive decline in plasma glucose throughout the study period. This disparity may be related to a relatively greater release of insulin and lesser rise in glucagon observed in diabetic subjects than in nondiabetic subjects. These preliminary findings suggest that further studies to elucidate the role of pancreatic beta-endorphin on glucoregulation may be rewarding.
The inhibitory role of the dopaminergic and opioidergic mechanisms in the control of LH secretion in patients with polycystic ovary syndrome (PCO) was evaluated. The administration of an opiate receptor antagonist, naloxone, of a dopamine receptor antagonist, metoclopramide, or of human synthetic beta h-endorphin, were unable to alter LH secretory activity in patients with PCO. Since identical doses of these antagonists and the opiate agonist have elicited respectively a rise and fall of LH levels in normal cycling women, these findings suggest that an underlying hypothalamic component of defect in endogenous dopamine and opioid control may be responsible for the inappropriate gonadotrophin secretion in this syndrome.
The gonadotropin-releasing activity of synthetic alpha MSH, previously found in normal men, was evaluated in women with different hormonal environments and in patients with acyclic gonadotropin release due to hypothalamic-pituitary dysfunction. alpha MSH (2.5 mg, iv) administered as either a single or two repeated pulses (at 2-h intervals) elicited unequivocal pituitary release of LH in normal women during the luteal phase and midcycle surge and in patients with functional hypothalamic amenorrhea, hyperprolactinemic amenorrhea, and polycystic ovary syndrome. Concomitant release of LH and FSH occurred only in polycystic ovarian syndrome patients and normal men. alpha MSH had no discernible effect on gonadotropin release in women during the early and late follicular phases of the cycle, in postmenopausal women, and in patients with isolated gonadotropin deficiency, even after pulsatile GnRH priming. The present observations confirm and extend our earlier finding that alpha MSH possesses gonadotropin-releasing activity in men and indicate that alpha MSH has similar properties in women with progesterone- and androgen-dominated environments or with specific types of hypothalamic-pituitary dysfunction marked by attenuated GnRH-LH release.
Twenty-four wethers were fed fresh cut orchardgrass, fertilized so that the magnesium concentration in the forage varied, and six lactating dairy cows were fed a 60% concentrate diet supplemented so that the magnesium concentration in the diet varied. This was to evaluate relationships between intake of magnesium and fecal excretion of magnesium in ruminants. Linear and logarithmic equations were evaluated for sheep and dairy cows. Although there was little difference between equations in ability to predict apparent absorption of magnesium at normal intakes of magnesium, the logarithmic equation was more useful for predicting magnesium apparent absorption at extreme intakes of magnesium. Constants for logarithmic equations for sheep and cows were similar; therefore, the data were combined and a single equation was derived for both species on the same logarithmic scale. Apparent absorption of magnesium in ruminants may be a function of the amount of magnesium consumed per unit of digesta surface area exposed to the rumen wall.
Explore the source record for details and available documents.
A step-by-step approach to the systematic management of chronic boutonniere deformity due to trauma is presented. If surgical intervention is necessary, the problem should be approached one step at a time. The following stages are described: stage I, tendolysis of the extensor tendon and freeing of the transverse retinacular ligament; stage II, sectioning of the transverse retinacular ligament; stage III, tendon lengthening of the lateral bands over the middle phalanx; and stage IV, repair of the central extensor tendon. After managing 23 patients according to this plan, we have concluded that it is frequently unnecessary to automatically go through all four stages in treating chronic traumatic boutonniere deformity. We found that 17 patients were successfully managed by some combination of stages I, II, and III, and six patients received adequate treatment with stages I, II, and IV.
In postmenopausal women, the administration of beta-endorphin in repeated pulses (1-2.5 mg) at 1- to 2-h intervals or constant infusion (1 mg/h) for 3-6 h elicited the prompt release of PRL without concomitant change in LH levels. Infusion of an opiate receptor antagonist, naloxone (1.6 mg/h), for 6-7 h also had no effect on LH levels. Since substantial evidence indicates that endogneous opioid peptides exert an inhibitory role on GnRH-LH secretion and that the functional activity of opiate receptors appears to be ovarian steroid dependent, the present observation suggests that the hypersecretion of gonadotropin in the absence of ovarian steroid feedback may, in part, be causally related to a reduced opioid inhibition of GnRH-LH release.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The premenstrual syndrome (PMS) is a major clinical entity afflicting a large segment of the female population. Available information are descriptive in nature and the etiology of this syndrome remains unclear. In this review, both biochemical and psychosocial elements of the syndrome have been explored in an effort to redefine the pathophysiology of this seemingly multifactorial psychoneuroendocrine dysfunction. We propose that luteal phase sensitivity to and subsequent withdrawal from the central effects of the neuropeptides beta-endorphin and alpha-melanocyte-stimulating hormone result in a cascade of neuroendocrine changes within the brain-hypothalamus-pituitary complex. Modulation of neurotransmitter function by these peptides may produce alterations in mood and behavior as well as enhance pituitary release of prolactin and vasopressin. Variable gonadal steroid modulation of these responses from subject to subject likely accounts for the heterogeneous clinical manifestations of the PMS.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The efficacy of intravenous and subcutaneous routes for pulsatile delivery of differing dosages of synthetic luteinizing hormone releasing factor (LRF) for ovulation induction were evaluated sequentially in two patients with presumed deficiency of endogenous LRF: isolated gonadotropin deficiency and pituitary stalk transection with hyperprolactinemia. Observations were made of the amplitude and duration of the induced LH-FSH pulses, of follicular growth and ovulation (via ultrasound), and of ovarian steroids. Remarkable differences in each of these parameters were found between the two modes of LRF delivery. LRF pulses administered subcutaneously resulted in inappropriate gonadotropin secretion, arrest of follicular development, elevated ratios of E1/E2 and androgens/estrogens, and the appearance of acne - features of polycystic ovary syndrome. In contrast, the first intravenous course of pulsatile LRF induced orderly follicular maturation and ovulation with subsequent pregnancy in both subjects. From these findings we conclude that, in these patients, the intravenous mode of delivery of LRF pulses was superior to the subcutaneous route at all doses tested.