scholarly journals Assessment of Isometric Muscle Exertion in Short-term Considering Task-rest Schedule

2021 ◽  
Vol 0 (0) ◽  
pp. 0-0
Author(s):  
Ali Chegini ◽  
Rouzbeh Ghousi ◽  
Hassan Sadeghi Naeini
Keyword(s):  
Author(s):  
Lise Sofie Bislev ◽  
Louise Wamberg ◽  
Lars Rolighed ◽  
Diana Grove-Laugesen ◽  
Lars Rejnmark

Abstract Background The role of vitamin D on muscle health is debated. Methods An individual participant metanalysis of four randomized placebo-controlled trials, investigating short term (three to nine months) effects of vitamin D3 in moderate (2800 IU) to high (7000 IU) daily oral doses on muscle health and quality of life (QoL). Inclusion criteria were either obesity (N=52), newly diagnosed primary hyperparathyroidism (N=41), Graves’ disease (N=86) or secondary hyperparathyroidism (N=81). Results Overall (N=260) as well as in a subgroup analysis including only vitamin D insufficient (25(OH)D< 50 nmol/L) individuals (N=176), vitamin D supplementation did not affect measures of muscle health (isometric muscle strength, Timed Up and Go test, Chair Rising Test, body composition, and balance) or QoL. However, a beneficial effect was present on QoL (physical component score) in vitamin D deficient (25(OH)D≤ 25 nmol/L) individuals (N=34). Overall, relative changes in 25(OH)D inversely affected maximum muscle strength in a dose response manner. Stratified into BMI </≥ 30 kg/m 2, vitamin D supplementation had divergent effects on isometric muscle strength, with beneficial effects in obese individuals (N=93) at knee flexion 90° (p=0.04), and adverse effects in non-obese individuals (N=167) at handgrip (p=0.02), knee extension 60° (p=0.03) and knee flexion 60° (p<0.01). Conclusion Overall, short-term treatment with moderate to high daily doses of vitamin D did not affect muscle health or QoL. A potential beneficial effect was present on muscle strength in severe obese individuals and on QoL in vitamin D deficient individuals. Subgroup analyses however suggested negative effects of large relative increases in p-25(OH)D.


Author(s):  
Dustin J. Oranchuk ◽  
André R. Nelson ◽  
Adam G. Storey ◽  
Shelley N. Diewald ◽  
John B. Cronin

Author(s):  
S. Nehal Safiya ◽  
G. Sridevi ◽  
S. Preetha

Aim: This study sets out to investigate whether a short-term isometric abdominal exercise can benefit adults with improvement in ventilatory functions. Materials And Methods: The present study was performed in 20 adults from the student population of I-BDS students with no history of smoking and respiratory illness. The participants did a daily 20-minute static abdominal exercise over a period of three days. The lung function test was assessed using spirometry and the values of FVC, FEV1, FEV1/FVC, PEFR, FEF 25-75. Paired dependent t test was done to evaluate the anthropometric variables and changes in lung functions pre-exercise on day 1 and post-isometric exercise on day 3.  Results: The study demonstrated a significant increase in the mean values of forced vital capacity and forced expiratory volume in one second. The FEV1/FVC ratio, PEFR, FEF 25-75% did not reveal significant changes. Conclusion: The study concluded an innovative finding that ventilatory functions improved after short term isometric training.


2016 ◽  
Vol 39 ◽  
Author(s):  
Mary C. Potter

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.


Author(s):  
M. O. Magnusson ◽  
D. G. Osborne ◽  
T. Shimoji ◽  
W. S. Kiser ◽  
W. A. Hawk

Short term experimental and clinical preservation of kidneys is presently best accomplished by hypothermic continuous pulsatile perfusion with cryoprecipitated and millipore filtered plasma. This study was undertaken to observe ultrastructural changes occurring during 24-hour preservation using the above mentioned method.A kidney was removed through a midline incision from healthy mongrel dogs under pentobarbital anesthesia. The kidneys were flushed immediately after removal with chilled electrolyte solution and placed on a LI-400 preservation system and perfused at 8-10°C. Serial kidney biopsies were obtained at 0-½-1-2-4-8-16 and 24 hours of preservation. All biopsies were prepared for electron microscopy. At the end of the preservation period the kidneys were autografted.


Author(s):  
D.N. Collins ◽  
J.N. Turner ◽  
K.O. Brosch ◽  
R.F. Seegal

Polychlorinated biphenyls (PCBs) are a ubiquitous class of environmental pollutants with toxic and hepatocellular effects, including accumulation of fat, proliferated smooth endoplasmic recticulum (SER), and concentric membrane arrays (CMAs) (1-3). The CMAs appear to be a membrane storage and degeneration organelle composed of a large number of concentric membrane layers usually surrounding one or more lipid droplets often with internalized membrane fragments (3). The present study documents liver alteration after a short term single dose exposure to PCBs with high chlorine content, and correlates them with reported animal weights and central nervous system (CNS) measures. In the brain PCB congeners were concentrated in particular regions (4) while catecholamine concentrations were decreased (4-6). Urinary levels of homovanillic acid a dopamine metabolite were evaluated (7).Wistar rats were gavaged with corn oil (6 controls), or with a 1:1 mixture of Aroclor 1254 and 1260 in corn oil at 500 or 1000 mg total PCB/kg (6 at each level).


Author(s):  
S.S. Poolsawat ◽  
C.A. Huerta ◽  
S.TY. Lae ◽  
G.A. Miranda

Introduction. Experimental induction of altered histology by chemical toxins is of particular importance if its outcome resembles histopathological phenomena. Hepatotoxic drugs and chemicals are agents that can be converted by the liver into various metabolites which consequently evoke toxic responses. Very often, these drugs are intentionally administered to resolve an illness unrelated to liver function. Because of hepatic detoxification, the resulting metabolites are suggested to be integrated into the macromolecular processes of liver function and cause an array of cellular and tissue alterations, such as increased cytoplasmic lysis, centrilobular and localized necroses, chronic inflammation and “foam cell” proliferation of the hepatic sinusoids (1-4).Most experimentally drug-induced toxicity studies have concentrated primarily on the hepatic response, frequently overlooking other physiological phenomena which are directly related to liver function. Categorically, many studies have been short-term effect investigations which seldom have followed up the complications to other tissues and organs when the liver has failed to function normally.


Author(s):  
D.E. Loudy ◽  
J. Sprinkle-Cavallo ◽  
J.T. Yarrington ◽  
F.Y. Thompson ◽  
J.P. Gibson

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.


2008 ◽  
Vol 45 ◽  
pp. 147-160 ◽  
Author(s):  
Jörg Schaber ◽  
Edda Klipp

Volume is a highly regulated property of cells, because it critically affects intracellular concentration. In the present chapter, we focus on the short-term volume regulation in yeast as a consequence of a shift in extracellular osmotic conditions. We review a basic thermodynamic framework to model volume and solute flows. In addition, we try to select a model for turgor, which is an important hydrodynamic property, especially in walled cells. Finally, we demonstrate the validity of the presented approach by fitting the dynamic model to a time course of volume change upon osmotic shock in yeast.


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