Paula Papanek

Association between the female athlete triad and endothelial dysfunction in dancers.

Objective:To determine the prevalence of the 3 components of the female athlete triad [disordered eating, menstrual dysfunction, low bone mineral density (BMD)] and their relationships with brachial artery flow-mediated dilation in professional dancers. Design:Prospective study. Setting:Academic institution in the Midwest. Participants:Twenty-two professional ballet dancers volunteered for this study. Interventions:The prevalence of the female athlete triad and its relationship to endothelial dysfunction. Main Outcome Measures:Subjects completed questionnaires to assess disordered eating and menstrual status/history. They also completed a 3-day food record and wore an accelerometer for 3 days to determine energy availability. Serum baseline thyrotropin, prolactin, and hormonal concentrations were obtained. Bone mineral density and body composition were measured with a GE Lunar Prodigy dual-energy X-ray absorptiometry. Endothelial function was determined as flow-mediated vasodilation measured by high-frequency ultrasound in the brachial artery. An increase in brachial diameter <5% to hyperemic flow stimulus was defined a priori as endothelial dysfunction. Results:Seventeen dancers (77%) had evidence of low/negative energy availability. Thirty-two percent had disordered eating (EDE-Q score). Thirty-six percent had menstrual dysfunction and 14% were currently using hormone contraception. Twenty-three percent had evidence of low bone density (Z-score < −1.0). Sixty-four percent had abnormal brachial artery flow-mediated dilation (<5%). Flow-mediated dilation values were significantly correlated with serum estrogen and whole-body and lumbar BMD. All the 3 components of the triad plus endothelial dysfunction were present in 14% of the subjects. Conclusions:Endothelial dysfunction was correlated with reduced BMD, menstrual dysfunction, and low serum estrogen. These findings may have profound implications for cardiovascular and bone health in professional women dancers.

Cigarette smoking, physical activity, and alcohol consumption: Relationship to blood lipids and lipoproteins in premenopausal females

A total of 164 premenopausal female subjects were randomly selected for evaluation from a much larger pool of volunteers. The relationships between blood lipid and lipoprotein levels as dependent variables and cigarette smoking, physical activity, and alcohol consumption were determined from partial regression coefficients. A lower HDL-C level (10.1 mg/dL) was seen in smokers v nonsmokers. For each ounce of alcohol consumed, HDL-C level was higher by 2.8 mg/dL, and greater physical activity was associated with a higher HDL-C level of 8.6 mg/dL. An analysis of covariance with covariance adjustments for age and body fat revealed that smokers who regularly exercise or consume alcohol had significantly lower HDL-C levels than nonsmokers with similar habits. Subjects who both exercise and consume alcohol demonstrated higher HDL-C levels than those who indulge in one or the other separately. Results suggest that cigarette smoking may attenuate the effects of chronic exercise or alcohol consumption, or of both, to raise HDL-C levels. Also, chronic exercise and alcohol consumption may exert an additive effect, raising HDL-C level.

Cigarette smoking, exercise and high density lipoprotein cholesterol

Cigarette smoking is associated with depressed levels of HDL-C, whereas exercise is associated with elevated levels of HDL-C. The purpose was to determine effects of smoking and exercise on blood lipids and lipoproteins in middle-aged males. It was hypothesized that smoking may attenuate the effects of exercise to elevate HDL-C. A total of 269 males (70 smokers) met all criteria for inclusion in the study population. Age, height, weight, body fatness via hydrostatic weighing, daily caloric consumption and alcohol intake, and smoking habits and history were determined. Interviews concerning physical activity patterns were conducted and cardiovascular responses to treadmill exercise were determined. Subjects were grouped as sedentary (low activity), participants in vigorous recreational activities (moderate activity) and joggers/runners (high activity). Analysis of covariance with adjustments for factors which may affect blood lipids and lipoproteins was employed. Smokers demonstrated lower HDL-C and higher total cholesterol levels than nonsmokers. High activity subjects demonstrated significantly higher HDL-C levels than the low and moderate groups which did not differ. High activity smokers did not differ from low activity nonsmokers with respect to HDL-C. This supports the proposed hypothesis. Nonsmokers were higher in weight and body fatness than smokers even though smokers consumed 288 more calories per day on the average. This suggests that smoking may account for a significant number of calories through altered metabolism or some other means.

Prevention of cold-induced increase in blood pressure of rats by captopril

To assess the possibility that the renin-angiotensin system may play a role in the development of cold-induced hypertension, three groups of rats were used. Two groups were exposed to cold (5±2°C) while the remaining group was kept at 26±2°C. One group of cold-treated rats received food into which captopril (0.06% by weight) had been thoroughly mixed. The remaining two groups received the same food but without captopril. Systolic blood pressure of the untreated, cold-exposed group increased significantly above that of the warm-adapted, control group within 4 weeks of exposure to cold. In contrast, chronic treatment with captopril prevented the elevation of blood pressure. Rats were killed after 4 months of exposure to cold. At death, the heart, kidneys, adrenal glands, and interscapular brown fat pad were removed and weighed. Although captopril prevented the elevation of blood pressure in cold-treated rats, it did not prevent hypertrophy of the kidneys, heart, and interstitial brown adipose tissue that characteristically accompanies exposure to cold. Thus, chronic treatment with captopril prevented the elevation of blood pressure when administered at the time exposure to cold was initiated. It also reduced the elevated blood pressure of cold-treated rats when administered after blood pressure became elevated. This suggests that the renin-angiotensin system may play a role in the elevation of blood pressure during exposure to cold.

A randomized controlled clinical trial to evaluate the effects of noncontact normothermic wound therapy on chronic full-thickness pressure ulcers.

OBJECTIVE To determine the effect of noncontact normothermic wound therapy (NNWT) versus standard wound care on chronic full-thickness pressure ulcers. DESIGN Prospective, randomized, controlled trial SETTING Veterans administration medical center and 7 long-term-care facilities PATIENTS 40 inpatients with 43 Stage III and IV pressure ulcers INTERVENTIONS A sterile noncontact wound dressing was applied to 21 wounds for 24 hours per day, 7 days per week. Each day after the wound was irrigated and the noncontact dressing was changed, a heating element in the dressing was activated for 3 1-hour periods for 12 weeks or until wound closure. Twenty-two control wounds were treated with standard, moisture-retentive dressings 24 hours per day, 7 days per week for 12 weeks or until wound closure. MAIN OUTCOME MEASURE Measurement of wound surface area MAIN RESULTS Healing rate for the NNWT group was significantly greater than for the control group (0.52 cm2 per week and 0.23 cm2 per week, respectively;P <.02). A clinically significant increase was seen among the NNWT group in the incidence of closure among wounds that completed the entire 12-week protocol compared with controls (11 of 14 or 79% and 8 of 16 or 50%, respectively; not significant). The mean slope of the individual regression analyses for the NNWT group was significantly different from the mean slope for the control group (−0.07 and −0.033, respectively;P <.05). Large wounds in the NNWT group demonstrated a significantly greater healing rate than large wounds in the control group (P <.05). CONCLUSION Wounds treated with NNWT healed significantly faster than wounds in the control group. The healing rate was greatest for larger wounds treated with NNWT.

Factors affecting cold-induced hypertension in rats.

Abstract A 3- to 4-week exposure of rats to a cold environment (5 ± 2°C) induces hypertension, including elevation of systolic, diastolic, and mean blood pressures and cardiac (left ventricular) hypertrophy. The studies described here were designed to investigate some factors affecting both the magnitude and the time course for development of cold-induced hypertension. The objective of the first study was to determine whether there was an ambient temperature at which the cold-induced elevation of blood pressure did not occur. The objective of the second experiment was to determine whether body weight at the time of exposure to cold affected the magnitude and time course for development of hypertension. To assess the first objective, male rats were housed in a chamber whose temperature was maintained at 5 ± 2°C while others were housed in an identical chamber at 9 ± 2°C. After 7 days of exposure to cold, the rats exposed to the colder temperature had a significant elevation of blood pressure (140 ± 2 mm Hg) compared with the group maintained at 9°C (122 ± 3 mm Hg). The rats exposed to 9°C had no significant elevation of systolic blood pressure at either 27 or 40 days after initiation of exposure to cold. At the latter time, the temperature in the second chamber was reduced to 5 ± 2°C. By the 25th day of exposure to this ambient temperature, the rats had a significant increase in systolic blood pressure above their levels at 9°C. Thus, there appears to be a threshold ambient temperature for elevation of blood pressure during exposure to cold. That temperature appears to lie somewhere between 5 and 9°C. The second objective was assessed by placing rats varying in weight from approximately 250 to 430 g in air at 5°C. There was a highly significant direct relationship (r = 0.96) between body weight at the time of introduction to cold and the number of days required to increase systolic blood pressure by 10 mm Hg above pre-cold exposure level. The third objective was to make an initial assessment of potential differences among strains of rats with respect to development of cold-induced hypertension. To this end, rats of the Fischer 344 strain were used. Systolic blood pressures of these rats also increased during chronic exposure to cold. Thus, both ambient temperature and body weight are important factors in the induction of hypertension in cold-treated rats. Furthermore, the development of cold-induced hypertension does not appear to be the function of a specific strain of rats. Hence, chronic exposure to cold appears to be a promising model for the induction of hypertension in rats without the need for surgical intervention, excessive doses of hormones, or genetic manipulation.

ACTH and Vasopressin Responses to Insulin-Induced Hypoglycemia in Intact and Neurohypophysectomized Conscious Dogs

Factors from the neurohypophysis are important in the control of anterior pituitary function. This study evaluated the hypothesis that the neurophypophysis is an integral component of the adrenocorticotropin (ACTH) response to certain stimuli. Furthermore, we investigated the possibility that the importance of the neurohypophysis during corticotropic stimuli can be classified by the magnitude of the systemic vasopressin response induced. The ACTH response to insulin-induced hypoglycemia (INS), nitroprusside hypotension (NP), or ovine corticotropin-releasing factor (CRF) infusion (20 ng/kg/min) was measured in dogs before (intact) and greater than 2 weeks after selective transbuccal neurohypophysectomy (NHX). INS (0.2 U/kg) resulted in a significant decrease in plasma glucose from 93 +/- 1 to 33 +/- 2 mg/dl at 30 min and a significant increase in plasma ACTH from 53 +/- 10 to 306 +/- 33 pg/ml in intact dogs whereas the vasopressin (AVP) response was small (2.8 +/- 0.3 to 5.5 +/- 0.7 pg/ml). NHX had no effect on the blood glucose or ACTH response to INS. NP resulted in large increases in ACTH from 54 +/- 8 to 351 +/- 89 pg/ml and in AVP from 2.7 +/- 0.2 to 272 +/- 98 pg/ml. In contrast to INS, NHX significantly attenuated the ACTH and AVP responses to NP. The ACTH response to CRF was not attenuated by NHX, indicating normal pituitary corticotropic function. In summary, NHX attenuated the ACTH response to hypotension (large peripheral AVP response) but not to INS or CRF (small peripheral AVP response).(ABSTRACT TRUNCATED AT 250 WORDS)

Folic Acid Supplementation Improves Vascular Function in Professional Dancers With Endothelial Dysfunction

To determine if folic acid supplementation improves vascular function (brachial artery flow‐mediated dilation [FMD]) in professional dancers with known endothelial dysfunction.

Citrate anticoagulation: Are blood donors donating bone?

An estimated 2.4 million volunteer apheresis blood donation procedures were performed in the United States in 2010, and increases in the proportion of transfused blood products derived from apheresis blood collections have been consistently reported. Anticoagulation is required during apheresis and is achieved with citrate. Donor exposure to citrate causes an acute physiological response to maintain serum mineral homeostasis. Some data are available on the sequelae of this acute response in the days and weeks following exposure, raising questions about bone mineral density in regular apheresis donors. New research is emerging that addresses the potential long‐term health outcomes of repeated citrate exposure. This article reviews the acute physiological response to citrate anticoagulation in volunteer blood donors, presents contrasting perspectives on the potential effects of citrate exposure on bone density, and identifies key knowledge gaps in our understanding of long‐term health outcomes in apheresis donors. J. Clin. Apheresis 31:459–463, 2016.

Effect of a Reduction in Sodium Intake on Cold-Induced Elevation of Blood Pressure in the Rat

Abstract Chronic exposure of rats to cold (5°C) induces hypertension within 3 weeks. The objective of this study was to determine the effect of treatment with graded levels of dietary NaCI on the induction of hypertension during chronic exposure to cold. Four groups of male rats were used. The first, given a commercial sodium-deficient diet containing 0.30% NaCI, served as the warm-adapted control group. The second, third, and fourth groups were given the same diet containing 0.075%, 0.15%, and 0.30% NaCI, respectively. Because cold-exposed rats ingest approximately twice as much food as warm-adapted controls, this represented half, the same, and twice the amount of NaCI ingested by the control group. The latter three groups were placed in cold air (5°C). All cold-treated groups had an elevation of systolic blood pressure that was proportional to the concentration of NaCI in the diet by the seventeenth week of exposure to cold. Cardiac hypertrophy occurred to the same extent in all cold-exposed groups and was thus unaffected by the NaCI content of the diet or by the extent of elevation of blood pressure. Hence, cardiac hypertrophy during chronic exposure to cold is supported by other factors, possibly by the increased concentration of either norepinephrine or triiodothyronine, or both, which occurs characteristically in rats under these conditions. The results of this experiment suggest that the amount of NaCI ingested daily plays a role in the cold-induced elevation of blood pressure observed in rats.