Experimental Research Into the Effect of Hyperbaric Exposures

Abstract Numerous research works indicate that staying in a hyperbaric environment is a stressor. We have undertaken studies using an animal model to determine the effect of hyperbaria on adrenocortical secretion and the level of adrenal ascorbic acid (a.a.a.). The research was conducted on 70 male hooded rats, which were divided into groups and subjected to hyperbaric air and oxygen at an overpressure of 1 and 3 atn, with some of the animals being additionally burdened with physical effort (swimming). It was found that short-term exposures (30 minutes) of rats to hyperbaric conditions caused a decrease in the content of a.a.a. With a prolonged (3-hour) exposure to 3 atm air the a.a.a. content returns to a normal level. A reduction in the a.a.a. content indicates the presence of stress in hyperbaric conditions in the rat, however, it does not allow to determine its intensity with the method used in the study.

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Determination of the L-ascorbic acid requirements in Wistar osteogenic disorder Shionogi rats for prolonged carcinogenesis experiments

Laboratory Animals ◽

10.1258/002367796780739826 ◽

1996 ◽

Vol 30 (4) ◽

pp. 337-346 ◽

Cited By ~ 10

Author(s):

S. W. Y. Chan ◽

P. C. Reade

Keyword(s):

Animal Model ◽

Ascorbic Acid ◽

Drinking Water ◽

Normal Level ◽

Physical Condition ◽

Wistar Rats ◽

Clinical Signs ◽

Supplement Group ◽

Palatal Mucosa

Wistar Shionogi rats of the ( od/od) substrain with the osteogenic disorder are unable to synthesize L-ascorbic acid ( L-AA) and appear to be an appropriate animal model for studying the effect of L-AA in carcinogenesis. To determine the minimal L-AA requirements of these animals for prolonged survival in a satisfactory physical condition during experimentation, four concentrations of L-AA (0.33 g/l, 0.67 g/l, 1.67 g/l and 3.33 g/l) were administered via drinking water to four groups of animals ( n=2). Their water intake per cage was recorded three times weekly and the plasma L-AA levels were determined at the start, after 2, 4, 8 and 12 weeks and at the termination of the experiment. To simulate the procedures to be undertaken in oral mucosal carcinogenesis experiments, the animals were gently restrained and a designated amount of sterile NaCl was applied to the palatal mucosa three times a week for 26 weeks. The L-AA supplement group with the lowest concentration (0.33 g/l L-AA) achieved mean plasma levels of 7 ± 1.38 μM, approximately one-eighth that of the normal level (mean plasma L-AA level in outbred Wistar rats was found to be 58 ± 3 μM) whilst those in the higher supplement group (3.33 g/l L-AA) achieved a mean of 18 ± 1.25 μM. All of the animals employed in the present study survived for 26 weeks and showed no clinical signs of L-AA deficiency during this period.

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Transgene stability and features of rasH2 mice as an animal model for short-term carcinogenicity testing

Molecular Carcinogenesis ◽

10.1002/mc.10045 ◽

2002 ◽

Vol 34 (1) ◽

pp. 1-9 ◽

Cited By ~ 15

Author(s):

Hiroshi Suemizu ◽

Kaori Muguruma ◽

Chika Maruyama ◽

Masashi Tomisawa ◽

Minoru Kimura ◽

...

Keyword(s):

Animal Model ◽

Short Term ◽

Transgene Stability ◽

Rash2 Mice

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Rabbit as an animal model for experimental research

Dental Research Journal ◽

10.4103/1735-3327.92960 ◽

2012 ◽

Vol 9 (1) ◽

pp. 111 ◽

Cited By ~ 81

Author(s):

BetsySara Thomas ◽

KM Bhat ◽

Manjeet Mapara

Keyword(s):

Animal Model ◽

Experimental Research

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Effect of Physical Exhaustion on Cognitive Functioning

Perceptual and Motor Skills ◽

10.2466/pms.1997.84.1.291 ◽

1997 ◽

Vol 84 (1) ◽

pp. 291-298 ◽

Cited By ~ 26

Author(s):

Y-A. Féry ◽

A. Ferry ◽

A. Vom Hofe ◽

M. Rieu

Keyword(s):

Reaction Time ◽

Perceived Exertion ◽

Short Term Memory ◽

Strenuous Exercise ◽

Decision Task ◽

Short Term ◽

Physical Effort ◽

Difficult Decision ◽

Central Processing ◽

Processing Resources

Experiments utilizing reaction time to measure the effects of fatigue on cognition must discern sensitivity of peripheral and central processing to strenuous exercise. The additive factors method enables one to stipulate that if fatigue interacts with subjects' reaction time in a decision task, central processing is affected by fatigue. While pedaling at different intensities, 13 physically-fit men had to perform a series of short-term memory tests. The tests were executed during a constant workload session and a progressive workload session in which subjects pedaled until exhaustion. Subjects provided ratings on Borg's 1970 scale to measure the psychological effects of the physical effort such as perceived exertion. Allocation of processing resources was also measured to determine attentional constraints exerted by the dual-task situation. Analysis showed that decision reaction time was affected only during the exhausting bout of the progressive workload session and for the more difficult decision task. We discuss our results in the context of arousal and the allocation of processing resources.

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Short-Term Appraisal of the Effects and Safety of Manual Versus Ventilator Hyperinflation in an Animal Model of Severe Pneumonia

Respiratory Care ◽

10.4187/respcare.06487 ◽

2019 ◽

Vol 64 (7) ◽

pp. 760-770 ◽

Cited By ~ 4

Author(s):

Gianluigi Li Bassi ◽

Joan Daniel Martí ◽

Talitha Comaru ◽

Eli Aguilera-Xiol ◽

Montserrat Rigol ◽

...

Keyword(s):

Animal Model ◽

Severe Pneumonia ◽

Short Term

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The study of the ferroconcrete beams with thrust on the foil bearings during short-term dynamic loading

MATEC Web of Conferences ◽

10.1051/matecconf/202031507003 ◽

2020 ◽

Vol 315 ◽

pp. 07003

Author(s):

Oleg Kumpyak ◽

Daud Galyautdinov

Keyword(s):

Dynamic Loading ◽

Experimental Research ◽

Fracture Strength ◽

Considerable Increase ◽

Intensity Increase ◽

Short Term ◽

Foil Bearings ◽

Horizontal Shift ◽

Power Intensity ◽

Positive Effect

While designing and maintaining ferroconcrete beam constructions subjected to a short-term dynamic loading, it is necessary to consider the emergence of the thrust reaction; this leads to a considerable increase of durability and fracture strength. It is also necessary to consider the use of foil bearings as the power-intensity increase of the researched constructions. The aim of the experimental research is to expose the reasonability of using foil bearings in thrust constructions. The paper presents the results of the experimental research of ferroconcrete beam constructions with thrust on foil bearings during short-term dynamic loading. The influence of the thrust on the durability, deformability and fracture strength of ferroconcrete constructions during short-term dynamic loading, as well as joint use of foil bearings and limitation of support contour horizontal shift are studied. The results of the research indicate the positive effect of using foil bearings in the constructions with thrust.

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