Increase In Body Water Research Articles

Copeptin in Growth Hormone-Treated Patients.

Growth hormone (GH) changes body composition, including increasing body water. GH is known to have an anti-natriuretic effect in the kidney, but little is known of its effect on arginine-vasopressin (AVP) release. We studied the effect of GH on AVP release by measurement of copeptin, a fragment from the same precursor protein, in GH-treated patients with GH deficiency. The study was designed as a retrospective cohort study of biobank samples from 34 patients substituted with GH between 1999 and 2004. Copeptin and insulin-like growth factor 1 (IGF-1) results were compared with previously obtained data. An increase in IGF-1 and copeptin was seen at 3 and 6 months’ treatment compared to baseline. Between the 3 and 6 months follow up, copeptin levels were stable. There was a difference in HbA1c between 3 and 6 months (p < 0.01) and between baseline and 6 months (p = 0.042), with higher levels at 6 months. In addition, LDL levels were lower at the 6 months follow up (p = 0.046). The waist circumference at 3 months was lower (p = 0.02). To conclude, three months of GH treatment increased the levels of copeptin and the increase remained at 6 months. This could be a compensatory mechanism balancing the anti-natriuretic effect of GH treatment seen in previous studies.

Impact of body fat, body water content, and skeletal muscle mass index on peak salivary lactate levels after squat jump exercise in healthy non-athlete adult males

BackgroundIn the rehabilitation and sports science fields, comprehensive assessment of the response to exercise is important for accurately prescribing exercise programs. Lactate is an important energy substrate that is frequently measured in clinical practice because it provides information on aerobic capacity. Salivary lactate, which can be measured non-invasively, has recently been focused on as an alternative to blood lactate. This study aimed to determine the combined effects of body fat, body water content, and skeletal muscle mass index on peak salivary lactate levels.MethodsThirty-seven non-athletic males performed a squat jump exercise. Their salivary lactate levels were measured before, immediately after, and every 5 min after the exercise using a simplified device. We also assessed body composition. A linear multiple regression analysis was performed with peak salivary lactate levels as the dependent variable and body fat ratio, body water content, and the skeletal muscle mass index as independent variables.ResultsThe participants’ body fat ratio (positive effect; p = 0.001) and body water content (negative effect; p = 0.035) significantly affected peak salivary lactate levels. Skeletal muscle mass index tended to positively influence salivary lactate levels (p = 0.099), albeit not significantly. The adjusted R-squared value of the model was 0.312 (p = 0.001).ConclusionsThe combined effect of body fat, body water content, and skeletal muscle mass index on peak salivary lactate levels was 31.2%. Better nutritional guidance may be effective in promoting weight loss and increasing body water content to improve aerobic capacity in the rehabilitation setting.

Early assessment of body composition in patients with liver transplantation

Rationale: Patients with liver cirrhosis frequently present alterations in body composition consisting of decreased muscle mass, increased body water and variable alterations in fat mass. The objective was to study body composition in the immediate postoperative period of liver transplantation, as well as 1 month later by bioimpedance measurement.

Physiological response of weaned piglets to two transport durations observed in a Canadian commercial setting.

Observational studies describing the impact of transport duration on weaned piglet welfare are limited. Current Canadian transport regulations are heavily informed by studies involving market hogs. Due to physiological differences between weaned piglets and market hogs, additional data on their response to transport are needed for age-specific evidence-based recommendations. A cohort study was conducted to describe and compare mortality, injury, weight change, hematological or biochemical changes in hydration, muscle injury and stress response observed in weaned piglets undergoing short duration (SD, <3 h), or long duration (LD, >30 h) commercial summertime transport events. Data collection on 440 of 11,434 transported piglets occurred the morning of the day before transport (T0), at arrival (T1) and approximately 3 to 4 d (78 to 93 h) after arrival at the nursery barn (T2). Low mortality occurred over all transport events (0.06%) with no association observed between transport duration and odds of death during transport (P = 0.62). The incidence of lameness between T0 and T1 was low (1.84% of the 435 focal piglets scored) with all lameness cases identified as mild in severity. Lesions on ears and skin were more prevalent than other injury types after transport (T1) and may have been related to mixing aggression associated with weaning rather than transport alone. LD piglets weighed 0.39 kg less than SD piglets at T1 (P < 0.01), but no difference in group weight was observed at T2 (P = 0.17). Hematological and biochemical differences were present between groups at T1. LD piglets had increased hematocrit levels compared with SD piglets (P = 0.01), suggesting increased body water losses. SD piglets showed greater levels of muscle injury compared with LD piglets including elevated aspartate aminotransferase (P < 0.01) and creatine kinase (P < 0.01). However, these parameters were within normal reference ranges for piglets of this age group. Indicators of physiological stress response including cortisol and neutrophil to lymphocyte ratios were elevated in SD piglets compared with LD piglets (P = 0.02 and P < 0.01, respectively). The results of this study demonstrate that both short and long transport durations can result in detectable physiological changes in weaned piglets. The overall impact of these durations on piglet welfare should be further explored by analyzing behavioral time budgets during and after transport.

Salt sensitivity of volume and blood pressure in a mouse with globally reduced ENaC γ-subunit expression.

The epithelial Na+ channel (ENaC) promotes the absorption of Na+ in the aldosterone-sensitive distal nephron, colon, and respiratory epithelia. Deletion of genes encoding subunits of ENaC results in early postnatal mortality. Here, we present the initial characterization of a mouse with dramatically suppressed expression of the ENaC γ-subunit. We used this hypomorphic (γmt) allele to explore the importance of this subunit in homeostasis of electrolytes and body fluid volume. At baseline, γ-subunit expression in γmt/mt mice was markedly suppressed in the kidney and lung, whereas electrolytes resembled those of littermate controls. Aldosterone levels in γmt/mt mice exceeded those seen in littermate controls. Quantitative magnetic resonance measurement of body composition revealed similar baseline body water, lean tissue mass, and fat tissue mass in γmt/mt mice and controls. γmt/mt mice exhibited a more rapid decline in body water and lean tissue mass in response to a low-Na+ diet than the controls. Replacement of drinking water with 2% saline selectively and transiently increased body water and lean tissue mass in γmt/mt mice relative to the controls. Lower blood pressures were variably observed in γmt/mt mice on a high-salt diet compared with the controls. γmt/mt also exhibited reduced diurnal blood pressure variation, a "nondipping" phenotype, on a high-Na+ diet. Although ENaC in the renal tubules and colon works to prevent extracellular fluid volume depletion, our observations suggest that ENaC in other tissues may participate in regulating extracellular fluid volume and blood pressure.NEW & NOTEWORTHY A mouse with globally suppressed expression of the epithelial Na+ channel γ-subunit showed enhanced sensitivity to dietary salt, including a transient increase in total body fluid, reduced blood pressure, and reduced diurnal blood pressure variation when given a dietary NaCl challenge. These results point to a role for the epithelial Na+ channel in regulating body fluid and blood pressure beyond classical transepithelial Na+ transport mechanisms.

Use of the Health Belief Model for Weight Control Promotion Using Vegetarian Meal Plans

A health belief model is used to evaluate people's beliefs about health problems and predict engagement in health-promoting behaviors. Overweight and obesity are health problems that could be corrected by healthier diet. Eighty-seven employees of the Taipei Tzu Chi Hospital participated in a month-long program that offered 500-calorie vegetarian meals. The health belief model questionnaire was designed and administered. Body composition (weight, body mass index, body fat, body water, and muscle mass) was measured weekly. Additionally, the number of meals taken and visits to nutrition consultants were analyzed. Overall, a higher perceived susceptibility was related to a decrease in weight, body fat, and muscle. Higher perceived benefits or higher perceived barriers were both related to a decrease in weight and body fat, but to an increase in body water and muscle. In the overweight or obese group, a significant correlation was found between perceived barriers and weight. No significant relationship was found between the health belief model and the total number of meals or number of visits to nutrition consultants. Perceived benefits and barriers were significantly related to changes in weight, body fat, body water, and muscle. With vegetarian meal plans as the cue for action, the health belief model can be utilized to predict changes in body composition.

Change in body weight, body fat and body water in children after tonsilloadenoidectomy

ObjectiveTo assess what was the cause of weight loss in children in early postoperative period after tonsilloadenoidectomy. Desing and settingProspective study conducted at Department of ENT, Head and Neck Surgery, General Hospital „Dr. Josip Benčević“ Slavonski Brod, Croatia. SubjectsIn total 31 patients aged 6–22 years that underwent tonsilloadenoidectomy. MethodsThe study was performed using specially designed questionnaires from January 2017 until August 2017. Results of pain assessment and administrated analgesic therapy, postoperative complications and inception of eating were completed through the questionnaire. During the study, children were weighed before tonsilloadenoidectomy, 24 h after tonsilloadenoidectomy and the seventh postoperative day where age, height, weight, body fat, body mass index (BMI), muscle mass and body water were recorded. Weighing was performed by the "Body Structure Analyzer BC-420MA" TANITA. ResultsData analysis revealed a significant reduction in mass, body fat, body mass index (BMI) and muscle mass in the children up to 10 years of age, as well as in the children that were 11 years and older. In children up to 10 years of age, there was no significant change in body water (%), while body water in the group of patients aged 11 and over was significantly higher on the seventh postoperative day (Friedman test, P = 0.02). In the total sample, there was a significant decrease in body weight, body fat (%), body mass index and muscle mass (Friedman test, P < 0.001), while there was a significant increase in body water (Friedman test, P = 0.003). There is no significant correlation between pain intensity and individual parameter change in all subjects, nor in age groups. ConclusionWater is an important factor of muscle mass. It plays an essential role in musle repair and growth, since it's crucial for protein synthesis. Poorly hydrated muscle loses it's weight, since musle cells don't have enough water in themselves. Good hydratation, especially among children up to 10 years old in early post tonsilloadenoidectomy period is important to keep muscular mass and power.

Investigating Changes in Weight and Body Composition Among Women in Adjuvant Treatment for Breast Cancer: A Scoping Review.

Despite several investigations, findings on weight changes during and after adjuvant treatment for breast cancer are diverse and point in several directions. The aims of this study were to investigate changes in weight and body composition associated with contemporary anticancer medication and to examine factors that might influence the assessment and diversity of the findings. This article used the method of a scoping review to map the body of literature. From searching the databases PubMed, CINAHL, and EMBASE using MeSH terms, CINAHL terms, and Emtree, as well as free text, 19 articles were selected for further investigation. The scoping review illustrates how findings in weight and body composition changes fluctuate over time as illustrated in 4 measure points: short term, 1 year, 18 months/2 years, and long term. The studies displayed differences regarding study designs, sample sizes, treatment regimens, measure points and techniques, and cutoff values for assessing weight changes, which make it difficult to synthesize findings and provide strong evidence for use in clinical practice. Synthesizing findings over time illustrates the need for attention on younger premenopausal women given chemotherapy. Weight need to be monitored for at least 2 years as short-term changes may be caused by increased body water, whereas long-term changes seem to be related with increased fat mass essential for risking recurrence and early death. The diversity in methods discloses the need for the research community to reach consensus regarding study designs for future research in this area.

Body Composition Technology: Implications for the ICU

Malnutrition continues to be highly prevalent in hospitalized and critically ill patients and is associated with significant morbidity and mortality. Additionally, survivors of critical illness have an increased risk for sarcopenia, which leads to weakness and physical debilitation that can persist for years. Nutrition risk assessment tools have been developed and validated in critically ill patients but have limitations. Variables such as body weight, body mass index, weight change, or percentage of food intake can be difficult to obtain in critically ill patients and may be misleading given changes in body composition, such as an increase in body water. Assessment of body composition through new techniques provides a unique opportunity to counter some of these limitations and develop improved methods of nutrition risk assessment based on objective data. The present manuscript provides a review of the most commonly available clinical technology for assessment of body composition (bioimpedance, computed tomography, and ultrasound), including data from trials in critically ill patients highlighting the benefits and weaknesses of each modality.

Clinical Aspects of Central Obesity at a Public Clinic

Background: The relation between central obesity epidemic and food consumption strategies has drawn attention towards understanding its complexity. The aim of our study is to evaluate clinical and nutritional aspects of women with central obesity in Salvador, Bahia. Methods: The study was done in 89 adult women with waist circumference > 84 cm after individualized outpatient consultations for 48 months (2012 - 2015). Direct interviews were performed with the application of three R24h recalls to evaluation of food consumption in relation to macronutrients, fiber and energy. The biochemical variables were determined in the blood collected with a 12-h fasting period. Results: There was a significant reduction in the waistline circumference baseline and final values, associated to a reduction in body fat percentage and a significant increase in body water. A significant reduction was observed in the consumption of carbohydrates in parallel to an increase in the consumption of fibers and 55 times in the percentage of consumption of lipids, in addition to a significant reduction in the baseline and final values of glycosylated hemoglobin, fasting glycemia and low-density lipoprotein cholesterol (LDL-C). Conclusions: It was observed that outpatient care with emphasis in the quality of the diet was capable of reducing anthropometric and clinical variables attributed to the development of illnesses associated with central obesity. J Endocrinol Metab. 2018;8(4):69-75 doi: https://doi.org/10.14740/jem516w

Hyponatremia in kidney transplant patients: its pathophysiologic mechanisms.

Kidney transplant patients (KTPs), and particularly those with advanced chronic kidney rejection, may be affected by opportunistic infections, metabolic alterations and vascular and oncologic diseases that promote clinical conditions that require a variety of treatments, the combinations of which may predispose them to hyponatremia. Salt and water imbalance can induce abnormalities in volemia and/or serum sodium depending on the nature of this alteration (increase or decrease), its absolute magnitude (mild or severe) and its relative magnitude (body sodium:water ratio). Hyponatremia appears when the body sodium:water ratio is reduced due to an increase in body water or a reduction in body sodium. Additionally, hyponatremia is classified as normotonic, hypertonic and hypotonic and while hypotonic hyponatremia is classified in hyponatremia with normal, high or low extracellular fluid. The main causes of hyponatremia in KTPs are hypotonic hyponatremia secondary to water and salt contraction with oral hydration (gastroenteritis, sepsis), free water retention (severe renal failure, syndrome of inappropriate antidiuretic hormone release, hypothyroidism), chronic hypokalemia (rapamycin, malnutrition), sodium loss (tubular dysfunction secondary to nephrocalcinosis, acute tubular necrosis, tubulitis/rejection, interstitial nephritis, adrenal insufficiency, aldosterone resistance, pancreatic drainage, kidney–pancreas transplant) and hyponatremia induced by medication (opioids, cyclophosphamide, psychoactive, potent diuretics and calcineurinic inhibitors). In conclusion, KTPs are predisposed to develop hyponatremia since they are exposed to immunologic, infectious, pharmacologic and oncologic disorders, the combinations of which alter their salt and water homeostatic capacity.

The Effect of Water Loading on Acute Weight Loss Following Fluid Restriction in Combat Sports Athletes.

Novel methods of acute weight loss practiced by combat sport athletes include "water loading," the consumption of large fluid volumes for several days prior to restriction. We examined claims that this technique increases total body water losses, while also assessing the risk of hyponatremia. Male athletes were separated into control (n = 10) and water loading (n = 11) groups and fed a standardized energy-matched diet for 6 days. Days 1-3 fluid intake was 40 and 100ml/kg for control and water loading groups, respectively, with both groups consuming 15ml/kg on Day 4 and following the same rehydration protocol on Days 5 and 6. We tracked body mass (BM), urine sodium, urine specific gravity and volume, training-related sweat losses and blood concentrations of renal hormones, and urea and electrolytes throughout. Physical performance was assessed preintervention and postintervention. Following fluid restriction, there were substantial differences between groups in the ratio of fluid input/output (39%, p < .01, effect size = 1.2) and BM loss (0.6% BM, p = .02, effect size = 0.82). Changes in urine specific gravity, urea and electrolytes, and renal hormones occurred over time (p < .05), with an interaction of time and intervention on blood sodium, potassium, chloride, urea, creatinine, urine specific gravity, and vasopressin (p < .05). Measurements of urea and electrolyte remained within reference ranges, and no differences in physical performance were detected over time or between groups. Water loading appears to be a safe and effective method of acute BM loss under the conditions of this study. Vasopressin-regulated changes in aquaporin channels may potentially partially explain the mechanism of increased body water loss with water loading.

Water Restrictions and Macronutrient Level Intake of Locust

Locust are grasshoppers that tend to migrate in swarms that can cause major damage to agriculture. Chortoicetes terminifera are locust native to Australian deserts, where they can potentially experience water restrictions. I hypothesized that water restriction would slow growth; and that high‐protein diets will be more deleterious under water‐restricted conditions because nitrogenous wastes require water to eliminate. Locusts were collected on the day they molted into the fifth (final) instar, weighed and placed in an individual plastic cage. Locusts received ad lib quantities of two different dry, granular diets: 35% protein:7% carbohydrate or 14% protein:28% carbohydrate. Locusts either had unlimited water or had ad lib access to water during every third day. All locust were given water on the day they molted for 24 hours. Then the locust on the restricted water treatment had no water for two days, followed by 24 hours with water, then 48 hours without water, continuing this pattern until the locust molted. After the locusts molted into adults, which took approximately 10 – 15 days, their final body mass (wet and dry) was recorded. Consumption rate was calculated by the loss in mass of the food pile over the entire instar, and their growth rates from the change in wet mass and development time (measured with a precision of ±1 day). Water restriction did not affect body water content or many measures of growth and size, suggesting this was a mild stress. Sexes differed in their responses, with water restriction reducing growth in males but not females. However, size and growth of females were much more affected by the diet than males; with the high‐protein diet strongly lowering body mass, food consumption and growth rate in females. Males consumed less of the high‐protein diet, but their adult mass and growth rate were unaffected by diet. High protein diets increased body water content for both sexes, possibly because high carbohydrate diets were associated with an increase in fat storage. There were few interactions between diet and water restriction, and contrary to our hypothesis, no consistent evidence that high‐protein diets were more deleterious under water restricted conditions. Future studies should examine the sex‐specific growth and metabolic responses to dietary protein:carbohydrate content. This research project was made possible thanks supported by the American Physiological Society and a grant from the National Science Foundation Integrative Organismal Systems IOS‐1238831 as well as the DEB 1313696, and CHE 1313958.Support or Funding InformationThis research project was made possible thanks supported by the American Physiological Society and a grant from the National Science Foundation Integrative Organismal Systems IOS‐1238831 as well as the DEB 1313696 and CHE 1313958.

Segmental extracellular and intracellular water distribution and muscle glycogen after 72-h carbohydrate loading using spectroscopic techniques.

Body water content increases during carbohydrate loading because 2.7-4-g water binds each 1 g of glycogen. Bioelectrical impedance spectroscopy (BIS) allows separate assessment of extracellular and intracellular water (ECW and ICW, respectively) in the whole body and each body segment. However, BIS has not been shown to detect changes in body water induced by carbohydrate loading. Here, we aimed to investigate whether BIS had sufficient sensitivity to detect changes in body water content and to determine segmental water distribution after carbohydrate loading. Eight subjects consumed a high-carbohydrate diet containing 12 g carbohydrates·kg body mass(-1)·day(-1) for 72 h after glycogen depletion cycling exercise. Changes in muscle glycogen concentration were measured by (13)C-magnetic resonance spectroscopy, and total body water (TBW) was measured by the deuterium dilution technique (TBWD2O). ICW and ECW in the whole body (wrist-to-ankle) and in each body segment (arm, trunk, and leg) were assessed by BIS. Muscle glycogen concentration [72.7 ± 10.0 (SD) to 169.4 ± 55.9 mmol/kg wet wt, P < 0.001] and TBWD2O (39.3 ± 3.2 to 40.2 ± 3.0 kg, P < 0.05) increased significantly 72 h after exercise compared with baseline, respectively. Whole-body BIS showed significant increases in ICW (P < 0.05), but not in ECW. Segmental BIS showed significant increases in ICW in the legs (P < 0.05), but not in the arms or trunk. Our results suggest that increase in body water after carbohydrate loading can be detected by BIS and is caused by segment-specific increases in ICW.

Plasma and liver metabolic profiles in mice subjected to subchronic and mild social defeat stress.

To improve the quality of life of animals, understanding of stress-induced changes is necessary. Previously, we established a subchronic and mild social defeat stress (sCSDS) model in mice, which showed significantly higher body weight gain, food intake, and water intake compared to control mice. In this study, we elucidated metabolic profiles of plasma, liver, and urine in sCSDS mice by using metabolome and biochemical analyses. There was no significant difference between defeated and control mice in the plasma metabolites. In the liver of sCSDS mice, levels of taurocyamine (GES), phosphorylcholine, D-alanyl-D-alanine (D-ala-D-ala), and 1-methylnicotinamide (MNA) were elevated compared to controls. Taurine plays a role in osmotic regulation, and GES is a potential inhibitor of the taurine transporter. The polydipsia and increased body water content in sCSDS mice may disrupt body fluid balance following GES elevation. Furthermore, sCSDS increased heart and spleen weight significantly. Because MNA and D-ala-D-ala have anti-inflammatory and hepatoprotective effects, they may reduce inflammation in the liver of sCSDS mice. Finally, suppressed excretion of urine sodium was observed in sCSDS mice. Therefore, sCSDS induces various changes in metabolite concentrations, especially related to osmoregulation and inflammation, that may be used as biomarkers for stress-induced changes in animals.

Bio-Impedance Analysis Measures in a Rural Latina Community

Obesity is an ever-growing epidemic that is accompanied by numerous comorbidities and exorbitant health care expenditures. The rural community in which this minority population was studied has the 7 th fattest population in the United States and is approximately 40% Hispanic 1 . In order to focus on interventions, bio-impedance analysis (BIA) was completed on a segment of the population as part of a community health assessment used in the Public Health Nursing Model. Forty-nine Latina women ages 20-80, attending a Latina Red Dress Event that targeted Heart Health of Latina women, were consented and measured for body composition on a bio-impedance analyzer. The items measured were BMI, body fat percentage, weight, height, body fat mass, fat free mass, visceral fat rating, body water percentage, body water mass, muscle mass, bone mass, basal metabolic rate, and metabolic age. Correlations and frequencies were analyzed for the variable data. State statistics indicate that approximately 60% of the population in this area is overweight or obese. The study findings show the rate is much higher in this segment of the population. Obesity is an ever-growing epidemic that is accompanied by numerous comorbidities and exorbitant health care expenditures. Rural areas in this country have higher rates of obesity than those of urban areas. Mexican Americans are at a higher risk for overweight and obesity and its comorbidities such as hypertension, diabetes, cardiovascular disease, joint disorders, psychological disorders, hyperlipidemia, cancers and asthma (1). This study was conducted in a rural mid-western area that has approximately 40% Mexican-American (2). The rural community where the study took place has the 7 th highest occurrence of obesity in the United States (3). In order to focus on obesity prevention interventions for this Hispanic population, bio-impedance analysis (BIA) was completed on a cohort of Hispanic mothers and abuelas (respected grandmothers) who attended a community health event. Hispanic mothers and abuelas were selected for this community health assessment. Significant relationships have been found between obese mothers and the risk for obesity in their children. The mothers and abuelas are also the primary caregivers who determine child feeding behaviors. The Public Health Nursing Model was used to guide the study design. Data from this study will be used to determine the need and direction for a future Hispanic abuela/mother intervention that will encourage healthy child feeding behaviors including limiting low nutrient carbohydrate intake and increasing body water. The overall objective is to help mothers eat, and drink healthier and feed their children in a similar manner to help prevent obesity in themselves and their children.

Resistance training promotes increase in intracellular hydration in men and women

The main purpose of the present study was to investigate the effect of 16 weeks of resistance training (RT) on body water in men and women. Thirty men (22.7 ± 4.4 years, 68.4 ± 9.0 kg and 174.5 ± 6.6 cm) and 34 women (22.7 ± 4.1 years, 58.8 ± 11.9 kg and 162.6 ± 6.2 cm) underwent progressive RT for 16 weeks (2 phases, 8 weeks each), 3 times per week, that consisted of 10–12 whole body exercises with 3 sets of 8–12 repetitions maximum. Total body water, TBW (intracellular water, ICW and extracellular water, ECW compartments) and skeletal muscle mass (SMM) were assessed using a spectral bioelectrical impedance device (Xitron 4200 Bioimpedance Spectrum Analyzer). TBW, ICW compartment and SMM increased significantly (P < 0.05) over time in men (+7.5%, +8.2% and +4.2%, respectively) and women (+7.6%, +11.0% +3.9%, respectively), with no sex by time interaction (P > 0.05). We conclude that progressive RT promotes an increase in body water, principally by intracellular content; however, the hydration status is not influenced by sex.

The Impact of Body Mass Index and Body Composition on Cardiac Autonomic Function in Young Adult Saudi Females

This work was carried out to elucidate the impact of body mass index, body fat and its distribution, body water and body muscles on the cardiac autonomic control in healthy young adult female students at King Abdulaziz University during 2012. Heart rate variability parameters were correlated with anthropometric measurements and body composition (fat, muscles and water). Time domain and frequency domain parameters of heart rate variability were decreased as the body mass index and percentage of body fat increase. In addition, these anthropometric measurements revealed significant positive correlations with the ratio of low frequency to high frequency components, pointing to the adverse effect of body fat on sympathovagal balance. Waist circumference, an index of central obesity, was negatively correlated with the number of pairs of successive NNs that differ by more than 50 ms. The percentage of body water showed a significant negative correlation with low frequency to high frequency ratio. Also, body muscles percentage represented a negative correlation with this ratio, though insignificant. Therefore, this study concluded that high indices of overall and central obesity seem to impair cardiac autonomic balance in healthy adult females. Additionally, increased body water and lean body mass are associated with favorable effects on cardiac autonomic function.

Sex-specific divergence for adaptations to dehydration stress in Drosophila kikkawai

Several studies on diverse Drosophila species have reported higher desiccation resistance of females, but the physiological basis of such sex-specific differences has received less attention. We tested whether sex-specific differences in cuticular traits (melanic females and non-melanic males) of Drosophila kikkawai correspond with divergence in their water balance mechanisms. Our results are interesting in several respects. First, positive clinal variation in desiccation resistance was correlated with cuticular melanisation in females but with changes in cuticular lipid mass in males, despite a lack of differences between the sexes for the rate of water loss. Second, a comparative analysis of water budget showed that females of the northern population stored more body water as well as hemolymph content and exhibited greater dehydration tolerance than flies from the southern tropics. In contrast, we found no geographical variation in the males for water content and dehydration tolerance. Third, an ~10-fold increase in the rate of water loss after organic solvent treatment of male D. kikkawai suggested a role of cuticular lipids in cuticular transpiration, but had no effect in the females. Fourth, geographical differences in the storage of carbohydrate content (metabolic fuel) were observed in females but not in males. Interestingly, in females, the rate of utilization of carbohydrates did not vary geographically, but males from drier localities showed a 50% reduction compared with wetter localities. Thus, body melanisation, increased body water, hemolymph, carbohydrate content and greater dehydration tolerance confer greater desiccation resistance in females, but a reduced rate of water loss is the only possible mechanism to cope with drought stress in males. Finally, acclimated females showed a significant increase in drought resistance associated with higher trehalose content as well as dehydration tolerance, while males showed no acclimation response. Thus, sex-specific differences in desiccation resistance of D. kikkawai are associated with divergence in some water balance strategies, despite a lack of differences in the rate of water loss between the two sexes.

Mood‐dependent changes of serum lithium concentration in a rapid cycling patient maintained on stable doses of lithium carbonate

Serum lithium levels may be influenced by mood state. We report on a 58-year-old female patient suffering from rapid cycling bipolar disorder. Her serum lithium levels varied greatly, despite stable medication. The patient was observed over a one-year period. The patient received a stable medication of lithium carbonate (450 mg), valproate (1500 mg), and clozapine (200 mg). Investigating mood and serum lithium levels over one year revealed six manic and six depressive phases. The mean lithium serum level was 0.67 mmol/L in the depressive states, 0.39 mmol/L in the manic states (t = 4.11, p = 0.001 versus depression), and 0.40 mmol/L in the euthymic states (t = 3.58, p = 0.003 versus depression). Noncompliance was ruled out. The patient gained up to 8 kg during manic phases, accompanied by pretibial edema. Changes in serum lithium concentration are probably not caused by altered lithium, but by water metabolism. During mania, body water increases, leading to dilution and therefore a reduction in serum lithium levels. As there is no proof for any other known cause of hypervolemia, we propose the hypothesis that the increase in body water is due to a variant of idiopathic edema.