Effects of Thermal Conditioning on Metabolic Responses of Rats to Altitude

1958 ◽  
Vol 195 (3) ◽  
pp. 735-738 ◽  
Author(s):  
Roy B. Mefferd ◽  
Henry B. Hale
Keyword(s):  
Weight Loss ◽  
Uric Acid ◽  
Urinary Excretion ◽  
Glutamic Acid ◽  
Strong Influence ◽  
Urine Volume ◽  
Barometric Pressure ◽  
Metabolic Responses ◽  
Different Temperatures ◽  
Per Se

The metabolic responses of rats acclimated to different temperatures (3°, 24° and 35°C) were compared during a 24-hour fasting exposure to low barometric pressure (380 mm Hg). Determinations included fasting weight loss, water intake, urine volume and urinary excretion of Na, K, Mg, Ca, PO4, urea, uric acid, creatinine, creatine, taurine, ß-alanine, glycine, α-alanine, valine + methionine, serine, threonine, tyrosine, glutamic acid, aspartic acid, lysine, arginine and histidine. Since the altitude tests were made at a neutral temperature (25°C) the altitude responses, per se, were determined by comparing the ground and altitude responses of each acclimated group at neutral temperatures. These comparisons revealed that the acclimated state of the rats exercised a strong influence on the altitude response for most of the variables. There were significant intergroup differences in this response for all variables except phosphate, urea, taurine, valine + methionine, serine, histidine and the Mg/Ca ratio.

Effects of Abrupt Temperature Changes on Excretion Characteristics of Rats Acclimated to Cold, Neutral or Hot Environments

1958 ◽  
Vol 195 (3) ◽  
pp. 726-734 ◽  
Author(s):  
Roy B. Mefferd ◽  
Henry B. Hale
Keyword(s):  
Weight Loss ◽  
Uric Acid ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Water Intake ◽  
Loss Rate ◽  
Urine Volume ◽  
Weight Loss Rate ◽  
Temperature Changes ◽  
Hot Environments

The responses of acclimated rats (heat, 35°C; neutral, 24°C; or cold, 3°C) to abrupt temperature changes (24-hr. exposure with fasting) are compared. Variables studied include weight loss, rate of fasting weight loss regain, water intake, urine volume, urinary Na, K, Ca, Mg, PO4, urea, uric acid, creatinine, creatine, taurine, ß-alanine, glycine, α-alanine, valine + methionine, serine, threonine, tyrosine, glutamic acid, aspartic acid, lysine, arginine and histidine. As compared to the neutral controls, most of the variables of the heat- and cold-acclimated rats were different under all conditions tested. Despite adaptive changes induced by the prior treatments, however, the changes directly attributable to abrupt environmental shifts were somewhat similar for the majority of the variables to those of the controls. Other variables in the cold-acclimated group tended toward nonresponsiveness, while the the heat-acclimated group tended toward overresponsiveness. Return to the neutral environment did not always result in a normalization, though the tendency was often in this direction.

Metabolic Responses to Thermal Stressors of Altitude-Acclimated Rats

1958 ◽  
Vol 195 (3) ◽  
pp. 739-743 ◽  
Author(s):  
Henry B. Hale ◽  
Roy B. Mefferd
Keyword(s):  
Urine Volume ◽  
Temperature Response ◽  
Ground Level ◽  
Metabolic Responses ◽  
Control Group ◽  
Response Curves ◽  
Level Pressure ◽  
Metabolic Functions ◽  
Per Se ◽  
The Difference

Fasting 24-hour exposures of altitude-acclimated rats (380 mm Hg, 18,000 ft. simulated) to ground level pressure (750 mm Hg) at either cold (3°C), neutral (24°C), or hot (35°C) temperatures seldom resulted in return of their metabolic functions to preacclimative ‘normalcy.’ Although the control and altitude-acclimated groups both were accustomed to neutral temperatures (24° and 26°C), quantitative differences at ground level and altitude occurred in various indices of water, mineral and nitrogen metabolism. Of the 32 physiologic variables studied, only 4 (ratio of urine volume/ water intake, and urinary excretion of potassium, creatinine and glycine) failed to differentiate the responses of the altitude- and ground-accustomed rats. The temperature response curves of the altitude group tended to parallel the corresponding ones for the control group, but most variables were on higher or lower planes. The difference in plane resulted either from the effects of the return to ground level pressure, or from nonreversible effects of acclimation to altitude per se.

Effects of somatotropin in rats acutely exposed to adverse environments

1961 ◽  
Vol 16 (1) ◽  
pp. 123-126 ◽  
Author(s):  
Henry B. Hale ◽  
Roy B. Mefferd
Keyword(s):  
Uric Acid ◽  
Urinary Excretion ◽  
Barometric Pressure ◽  
Metabolic Effects ◽  
Subcutaneous Injections ◽  
Suggestive Evidence ◽  
Temperature And Pressure ◽  
Induced Changes ◽  
Neutral Conditions ◽  
Adverse Environments

Metabolic effects of acute (24-hr.) exposure to low barometric pressure (380 mm Hg), heat (35°C), or cold (2°C) were determined in fasting rats which had received subcutaneous injections of somatotropin (0.5 mg/100 gm b.wt.) 24 hours before and immediately before exposure. Comparison was made with rats exposed to the same conditions without pretreatment with somatotropin and with controls held under neutral conditions of temperature and pressure (24°C, 750 mm Hg). Somatotropin modified environmentally induced changes in 24-hour urinary excretion of urea, uric acid and phosphate and the urinary Na/K, Ca/P and uric acid/creatinine ratios. Suggestive evidence was thus obtained to support the hypothesis that somatotropin contributes to homeostasis. Submitted on October 26, 1959

Factorial Study of Environmentally-Induced Metabolic Changes in Rats

1958 ◽  
Vol 194 (3) ◽  
pp. 469-475 ◽  
Author(s):  
Henry B. Hale ◽  
Roy B. Mefferd
Keyword(s):  
Amino Acids ◽  
Body Weight ◽  
Uric Acid ◽  
Chronic Exposure ◽  
Urine Volume ◽  
Ground Level ◽  
Barometric Pressure ◽  
Metabolic Effects ◽  
Body Weight Change ◽  
Metabolic Functions

Metabolic effects of chronic exposure to combinations of adverse environmental influences were studied in rats. During exposures lasting 12 weeks, rats were subjected to the barometric pressure equivalent to 18,000 feet altitude at temperatures ranging from 5° to 34°C. Controls at the various temperatures were held at ground level (700 ft. above sea level). Biweekly observations showed that metabolic functions (water, electrolyte and nitrogen) were influenced primarily by the thermal factors, but altitude effects could also be distinguished. Observations are reported for survival, body weight change, water and food intake, urine volume and the urinary excretion of Na, K, PO4, Mg, Ca, urea, uric acid, creatinine, taurine and 10 amino acids.

Polyvinyl fibers as outperform candidature in the solid polymer electrolytes

2020 ◽  
pp. 152808372097062
Author(s):  
Muhammad Yameen Solangi ◽  
Umair Aftab ◽  
Muhammad Ishaque ◽  
Aqeel Bhutto ◽  
Ayman Nafady ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Weight Loss ◽  
Ionic Conductivity ◽  
Polymer Electrolytes ◽  
Vital Role ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Main Challenge ◽  
Different Temperatures ◽  
Solution Cast

Solid polymer electrolytes (SPEs) are the best choice to replace liquid electrolytes in supercapacitors, fuel cells, solar cells and batteries. The main challenge in this filed is the ionic conductivity and thermal stability of SPEs which is still not up to mark, therefore more investigations are needed to address these issues. In this study, PVA/salt based SPEs was fabricated using both solution cast and electro-spinning methods to probe the effect of different salts such as (NaCl, KCl and KI) and their concentrations on the ionic conductivity. Scanning electron microscopy (SEM) x and Fourier Transform Infra-Red (FTIR) have been employed to study the morphology as well as the different functional groups of SPEs, respectively. It was noted that small addition of NaCl, KCl and KI salts in SPEs dramatically increased the ionic conductivity to 5.95×10−6, 5.31×10−6 and 4.83×10−6 S/cm, respectively. Importantly, the SPEs obtained with NaCl via electro-spinning have higher ionic conductivity (5.95×10−6 S/cm) than their casted SPEs (1.87×10−6 S/cm). Thermal stability was also studied at two different temperatures i.e. 80 °C and 100 °C. The weight loss percentage of electrospun SPEs have zero percent weight loss than the solution based SPEs. The combined results clearly indicated that the nature of salt, concentration and fabrication process play a vital role in the ionic conductivity. Also, the NaCl salt with low molecular weight at low concentrations shows an enhanced ionic conductivity.

scholarly journals Uric acid is associated with adiposity factors, especially with fat mass reduction during weight loss in obese children and adolescents

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Yang Niu ◽  
Xue-lin Zhao ◽  
Hui-juan Ruan ◽  
Xiao-meng Mao ◽  
Qing-ya Tang
Keyword(s):  
Weight Loss ◽  
Body Composition ◽  
Uric Acid ◽  
Children And Adolescents ◽  
Body Fat ◽  
Fat Mass ◽  
Dietary Control ◽  
Obese Children ◽  
Fat Percentage ◽  
Before And After

Abstract Background Current adult studies suggest that uric acid (UA) is associated with body fat, but the relationship in obese children is unclear. Thus, we aim to evaluate the association between uric acid and body composition of obese children. Methods A total of 79 obese children were included in this study, and 52 children (34 boys and 18 girls) underwent a 6-week weight loss camp, including 34 boys and 18 girls. Six-week weight-loss interventions were performed on all participants through aerobic exercise and appropriate dietary control. Laboratory tests and body composition were collected before and after the intervention. Results Before the intervention, correlation analysis demonstrated that uric acid was positively correlated with height, weight, body mass index (BMI), waist circumference, hip circumference, fat mass (FM), and free fat mass (FFM) with adjusting for age and gender (P < 0.05). After 6 weeks of intervention, the participants gained 3.12 ± 0.85 cm in height, body fat percentage decreased by 7.23 ± 1.97%, and lost 10.30 ± 2.83 kg in weight. Univariate and multivariate analysis indicated that uric acid at baseline was associated with FM reduction during weight loss (P < 0.05). Conclusions This study is the first report that uric acid is associated with BMI and FM, and may play an important role in the reduction of FM during weight loss in obese children and adolescents. The interaction between UA and adiposity factors and its underlying mechanisms need to be further explored. Trial registration This study was registered in Clinical Trials.gov (NCT03490448) and approved by the Ethics Committee of Xinhua Hospital, Shanghai Jiao Tong University School of Medicine.

Assessment of Cardiorespiratory and Metabolic Responses in Women with Obesity After Surgically Induced Weight Loss: Results from a Pilot Study

2021 ◽  
Author(s):  
Tatiana Onofre ◽  
Nicole Oliver ◽  
Renata Carlos ◽  
Davi Fialho ◽  
Renata C. Corte ◽  
...  
Keyword(s):  
Weight Loss ◽  
Pilot Study ◽  
Metabolic Responses ◽  
Surgically Induced

Nephrolithiasis

2018 ◽  
Author(s):  
José Luiz Nishiura ◽  
Ita Pfeferman Heilberg
Keyword(s):  
Uric Acid ◽  
Calcium Oxalate ◽  
Dietary Habits ◽  
Stone Formation ◽  
Urine Volume ◽  
First Episode ◽  
Dietary Advice ◽  
Dietary Recommendations ◽  
Genetic Traits ◽  
Oxalate Precipitation

Nephrolithiasis is a highly prevalent condition, but its incidence varies depending on race, gender, and geographic location. Approximately half of patients form at least one recurrent stone within 10 years of the first episode. Renal stones are usually composed of calcium salts (calcium oxalate monohydrate or dihydrate, calcium phosphate), uric acid, or, less frequently, cystine and struvite (magnesium, ammonium, and phosphate). Calcium oxalate stones, the most commonly encountered ones, may result from urinary calcium oxalate precipitation on the Randall plaque, which is a hydroxyapatite deposit in the interstitium of the kidney medulla. Uric acid nephrolithiasis, which is common among patients with metabolic syndrome or diabetes mellitus, is caused by an excessively acidic urinary pH as a renal manifestation of insulin resistance. The medical evaluation of the kidney stone patient must be focused on identifying anatomic abnormalities of the urinary tract, associated systemic diseases, use of lithogenic drugs or supplements, and, mostly, urinary risk factors such as low urine volume, hypercalciuria, hyperuricosuria, hypocitraturia, hyperoxaluria, and abnormalities in urine pH that can be affected by dietary habits, environmental factors, and genetic traits. Metabolic evaluation requires a urinalysis, stone analysis (if available), serum chemistry, and urinary parameters, preferably obtained by two nonconsecutive 24-hour urine collections under a random diet. Targeted medication and dietary advice are effective to reduce the risk of recurrence. Clinical, radiologic, and laboratory follow-ups are needed to prevent stone growth and new stone formation, to assess treatment adherence or effectiveness to dietary recommendations, and to allow adjustment of pharmacologic treatment. This review contains 5 highly rendered figure, 3 tables, and 105 references.

Hygroscopic properties of thermally modified false Iroko [Antiaris toxicara (Lesch)]

2021 ◽  
Vol 18 (1) ◽  
pp. 51-57
Author(s):  
F.A. Faruwa ◽  
K. Duru
Keyword(s):  
Weight Loss ◽  
Dimensional Stability ◽  
Thermal Process ◽  
Colour Change ◽  
Wood Properties ◽  
Thermal Modification ◽  
Hygroscopic Properties ◽  
Different Temperatures ◽  
Thermally Modified Wood ◽  
Modified Wood

The study investigated the use of thermal modification to improve the hygroscopic properties of False Iroko [Antiaris toxicaria (Lesch)]. Samples of Antiaris toxicara Lesch wood were subjected to thermal modification in a furnace at temperatures of 160, 180 and 200°C for 30 and 60 minutes. Results showed that wood properties were improved with exposure to different temperatures. Subsequent to the thermal process, a colour change from pale yellow to darkish brown was observed progressively with increase in temperature, accompanied by a weight loss in the range of 12.08% to 23.67%. The outcome of these treatments resulted in a decrease in volumetric swelling and increase in dimensional stability of modified wood; this can be attributed to observed decrease in moisture intake. The thermal modification of Antiaris toxicara Lesch wood affected the dimensional stability properties. Thus, due to significant changes via modification carried out on the selected species which is classified as lesser utilized wood species, lesser utilized wood,Antiaristoxicara Lesch wood is recommended for use due to its efficient dimensional stability after modification . keywords:, Thermally modified wood ;False Iroko

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