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M Ware

Publications and source records attributed to M Ware.

27 records · Page 2Linked to original sources

Effects of dietary protein deficiency on mineral metabolism and bone mineral density.

The effects of dietary protein restriction on mineral and bone metabolism are uncharacterized. We studied growing rats fed a diet low in protein (5%) for 4, 6, and 8 wks (n = 10 animals/group) and compared them with animals pair-fed with a protein-replete (18%) diet. The low-protein diet rapidly induced a profound hypocalciuria that persisted for greater than or equal to 8 wk. Serum calcium and phosphorus concentrations were not affected but serum total and free 25-dihydroxyvitamin D concentrations as well as gastrointestinal calcium absorption were lower in the low-protein animals. Skeletal dimensions were reduced in the protein-deprived rats but there were no significant differences in bone mineral content between control and low-protein animals at 4, 6, and 8 wks. Hence, dietary protein deprivation resulted in slower growth but bone mineral density was maintained when there was a marked reduction in urinary calcium excretion.

Animals↗

Combination estrogen and progestogen replacement therapy does not adversely affect coagulation.

Coagulation and fibrinolysis profiles of naturally menopausal women receiving conjugated estrogens (0.625 or 1.25 mg for 21 of 28 days) and medroxyprogesterone acetate (10 mg for seven of 28 days) for 18 months were compared with those of similar women receiving no hormone therapy. Tests indicative of the dynamics of the coagulation cascade, ongoing intravascular coagulation, and anticoagulation were performed. Hormone therapy had no effect on prothrombin times, activated partial thromboplastin times, or thrombin times. There was no evidence of intravascular coagulation in any of the groups as assessed by platelet counts, fibrinogen antigen and activity, and fibrin degradation products. Antithrombin III antigen and activity, alpha 1-antitrypsin antigen, and alpha 2-macroglobulin antigen, the natural inhibitors of coagulation, were also unaffected by hormone therapy. Plasminogen antigen levels were unaffected, but plasminogen activity was enhanced in the hormone-treated groups, suggesting a stimulatory effect on fibrinolysis. These data indicate that in terms of the coagulation system, healthy women can safely use a combined regimen of conjugated estrogens and medroxyprogesterone acetate.

Androstenedione↗

The short term distribution of thiopentone in the dog.

Rapid sampling of arterial blood following intravenous infusion of thiopentone at various speeds has demonstrated that the peak concentrations for doses given over five seconds are at least twice those for doses given over fifteen seconds. The area under the curves and the dispersed arterial concentrations show no significant difference between infection speeds.

Animals↗

Increased neuropeptide Y concentrations in specific hypothalamic nuclei of the rat following treatment with methysergide: evidence that NPY may mediate serotonin's effects on food intake.

Neuropeptide Y (NPY) is a potent central appetite stimulant found in hypothalamic neurons that have close anatomical associations with neurons containing serotonin, a powerful anorectic agent. To determine whether the two neurotransmitters interact functionally, we have studied the effects on regional hypothalamic NPY concentrations of acute and chronic administration of methysergide, a 5-HT1BC/serotonin receptor antagonist. Chronic methysergide treatment (10 mg/kg/day) was given by subcutaneously implanted osmotic minipumps (n = 8). Acute effects of methysergide were determined 4 h after a single injection (10 mg/kg) in a separate group (n = 8). Controls (n = 8) had implanted minipumps delivering saline, and also received a saline injection 4 h before sacrifice. Food intake was significantly increased (p < 0.01) by both acute and chronic methysergide treatment. In the chronically treated rats, NPY levels were significantly increased over controls in the arcuate nucleus (ARC; by 41%, p = 0.02) and paraventricular nucleus (PVN; by 40%, p < 0.01). Acute methysergide treatment also increased NPY concentrations in the ARC (by 81%, p < 0.01) and PVN (by 30%, p < 0.01). Methysergide administration, which stimulated feeding, therefore raised NPY concentrations in the ARC, where NPY is synthesized, and in the PVN, a major site of NPY release where NPY injection induces hyperphagia. These findings suggest that NPYergic and serotoninergic innervations in the hypothalamus interact to regulate food intake, and raise the possibility that increased NPY release may mediate the hyperphagic effect of serotoninergic 5-HT1BC/receptor blockade.

Animals↗

Lack of relationship between sympathetic nervous system activity, measured by two circulating markers, and blood pressure in diabetic and nondiabetic subjects.

Two putative sympathetic nervous system (SNS) markers, noradrenaline and neuropeptide Y (NPY) were related to 24-h ambulatory blood pressure (BP) in 59 normotensive subjects, 34 non-insulin-dependent diabetics, and 25 controls. Plasma NPY levels were not significantly different between the two groups [non-insulin-dependent (NIDDM) diabetes mellitus 4.33 (3.25-5.78), controls 5.68 (3.39-6.97) p=0.26] as were those of noradrenaline (1.51+/-0.69 versus 1.78+/-0.55; p=0.053). There were correlations, controlled for age and obesity, of plasma NPY with clinic and night time diastolic BP in the control group only (r=0.49 [p=0.013] and r=0.48 [p=0.023] respectively). No similar correlation was found in the NIDDM group, or between plasma noradrenaline and blood pressure in either group. No correlation was found between plasma insulin and NPY or noradrenaline levels. There is a weak independent relationship between NPY and blood pressure in normotensive nondiabetics but not in NIDDM subjects. We found no evidence for the hypothesis that insulin modulates blood pressure through activity of the SNS.

Adult↗