Independently living older adults (over the age of 65 yr) consume adequate volumes of fluids on a daily basis. However, when challenged by fluid deprivation, a hyperosmotic stimulus, or exercise in a warm environment (all of which combine hypovolemia and hyperosmolality), older adults exhibit decreased thirst sensation and reduced fluid intake. Full fluid restoration eventually occurs, but full restoration of fluid balance is slowed. The aging process alters important physiological control systems associated with thirst and satiety. Recent evidence suggests that older men and women (i) have a higher baseline osmolality and thus a higher osmotic operating point for thirst sensation (with little or no change in sensitivity), and (ii) exhibit diminished thirst and satiety in response to the unloading (hypovolemia) and loading (hypervolemia) of baroreceptors. A diminished sensation of thirst in the elderly relative to young adults is generally absent when a volume stimulus is absent, despite higher baseline plasma osmolalities. Compared with the elderly, there are scant data associated with homeostatic control of thirst in children. Nonhomeostatic control of thirst and drinking behavior may likewise be different for children (as it is for the elderly), as compared with young adults; however, little empirical data exist on this topic. Children rarely exhibit voluntary dehydration for activities lasting 45 min or less; however, drink flavoring and sodium chloride are important promoters of drinking in active children.
Polycystic ovary syndrome (PCOS) is a heterogeneous disorder of unexplained hyperandrogenic chronic anovulation. Experts have recommended including the morphology and volume of the ovary in the diagnostic criteria for PCOS. We performed this study to determine whether there was an association between the morphology and size of the ovaries and markers of insulin sensitivity as determined by dynamic testing within women with PCOS or compared with a group of control women. We then examined reproductive parameters. We studied 88 unrelated PCOS women and 21 control women, aged 17-45 yr. All were in the early follicular phase or its equivalent (no follicle with > 10 mm diameter and anovulatory serum progesterone level < 3 ng/ml). Subjects underwent on the same day a phlebotomy for baseline hormones, a 2-h oral glucose tolerance test, and transvaginal ultrasound to determine the morphology and volume of the ovaries. Ninetyfive percent (84 of 88) of women with PCOS and 48% (10 of 21) of the control women had polycystic ovaries using the criteria of at least one ovary greater than 10 cm 3 (PCOV) and/or polycystic ovary morphology (PCOM) using the criteria of 10 or more peripheral follicular cysts 8 mm in diameter or less in one plane along with increased central ovarian stroma. PCOM was a better discriminator than PCOV between PCOS and control women. The odds of women with PCOS having PCOM were elevated 50-fold compared with controls (odds ratio, 50; 95% confidence interval, 10 -240; P < 0.0001), whereas the odds of PCOV were elevated 5-fold in women with PCOS (odds ratio, 4.6; 95% confidence interval, 1.7-12.6; P ؍ 0.003). Neither the insulin sensitivity index, fasting or 2-h values, or any integrated measures of glucose and insulin varied in women according to either morphology or volume, nor was there an association with circulating androgen levels. Women with PCOS and PCOM had lower FSH levels than women with PCOS and non-PCOM. Women with PCOS and PCOV had a higher LH to FSH ratio than women without PCOV and PCOS. These data support the hypothesis that polycystic ovaries are an abnormal finding. However, neither the morphology nor the volume of the ovaries is associated with distinctive metabolic or reproductive phenotypes in women with PCOS.
The authors present the results of a randomized, controlled trial comparing microwave endometrial ablation (MEA) performed after 1 month of hormonal preparation of the endometrium with MEA performed immediately after menses with no uterine preparation. Study subjects were 210 women with excessive menstrual bleeding who were willing to undergo MEA under local anesthesia. Thirteen of the 210 patients withdrew from the study after randomization. One hundred of the remaining 197 women were randomized to receive either 200 mg danazol twice a day for 4 to 5 weeks or one injection of 3.6 mg goserelin subcutaneously 5 weeks before the procedure, and 97 were randomized to undergo MEA from day 3 to day 10 of their menstrual cycle without hormonal pretreatment. All patients were analyzed on an intent-to-treat basis, including 3 women in the postmenstrual group who accidentally received drugs for endometrial preparation.Before treatment, patients received a vaginal suppository containing 100 mg Voltarol or 1 g paracetamol and were offered preoperative intravenous sedation with midazolam (2-4 mg maximum). Intraoperative analgesia with intravenous fentanyl (25-50 g intravenously maximum) was available on request.Clinical, personal, and quality-of-life information was obtained through patient questionnaire completed before the procedure. In addition, questionnaires concerning clinical information and financial matters were completed postoperatively, at 2 weeks or 1 month, at 6 months, and at 12 months after treatment.The costs of each treatment method were evaluated, including treatment preparation, procedure, other drugs, hospitalization, and postoperative clinic and physician visits.In the drug treatment arm, 3 procedures were not completed. Two women experienced severe pain during MEA and were rescheduled for treatment under general anesthesia. The third patient had severe cervical stenosis and a false passage was created during attempted cervical dilation. She declined further treatment. In the postmenses arm, one woman had a vasovagal reaction early in the MEA process and was scheduled to have the procedure under general anesthesia. There were no other perioperative complications.There were no significant differences between treatment groups in reported levels of pain or discomfort associated with MEA. Requirements for intraoperative anesthesia were the same for both groups, but women who received preoperative drug preparation needed less postoperative pain relief. An overnight hospital stay was more common among women who received hormones than among those who did not (20% vs 12%). Two weeks after treatment, 90% GYNECOLOGY Volume 60, Number 12 OBSTETRICAL AND GYNECOLOGICAL SURVEY 792 of the postmenses group found the procedure totally or generally acceptable compared with 76% of those in the drug treatment group. More patients who had MEA after menses returned to normal activities within 3 days of treatment than did patients who had endometrial preparation (46% vs 28%). In the month before MEA, those who received hormonal...
The present study was conducted to determine whether porcine somatotropin (pST) differentially regulates expression of the GLUT4 and fatty acid synthase (FAS) genes in pig adipose tissue. Three different experiments were conducted in which pigs were treated daily with different doses of pST for different time periods (7 or 14 d and from 60 to 90 kg of body wt). In these experiments, pST significantly and consistently decreased FAS mRNA levels (80%, 66% and 85%, respectively); however, GLUT4 mRNA was not affected by pST in two of the three experiments, and in the one showing an effect (Experiment 2), the decrease was less than observed for FAS (44%). Because of these results, we conducted subsequent experiments to see if the effects of pST on glucose metabolism in cultured pig adipose tissue (48 h) differed when glucose concentrations were changed from 1 to 5 mmol/L. These studies revealed that the antagonistic effect of pST on insulin action was more potent when glucose transport was saturated (5 mmol/L) than when glucose concentration limited glucose entry into the cell (1 mmol/L). In summary, these results suggest that the effects of pST on glucose transport in pig adipocytes are secondary to changes elicited by the hormone on intracellular glucose use for lipogenesis. When considered in the context of the decrease previously observed in glucose transport in pig adipocytes, the findings reported herein suggest that pST acts to decrease GLUT4 protein activity and/or distribution between the plasma membrane and the intracellular pool with little alteration in GLUT4 gene expression or total cell GLUT4 protein.
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