Segmental Volume and Circulatory Changes that Occur in Humans and Rhesus Monkeys During 4 Hour, -6 Degree Head Down Tilt.

Nonhuman primates are often used to investigate physiologic processes that occur in man during aerospace/cardiovascular orthostatic research. Few studies have compared nonhuman primates and man under identical test conditions to assess the degree of similarity between the two species. Impedance plethysmography was used to measure calf, thigh, pelvic, thoracic, upper arm, and lower arm volume changes in eight rhesus (Macacca Mulatta) monkeys and twelve human subjects during four hour exposures to -6 degree head down tilt (HDT).

Segmental Volume Changes that Occur in Nonhuman Primates During Short Term Head Up (HUT) and Head Down (HDT) Tilt.

Nonhuman primates are often used in biomedical research and to investigate physiologic processes that occur in man. Impedance plethysmography was used to measure calf, thigh, pelvic, abdominal, and thoracic volume changes in ten Rhesus and eight squirrel monkeys during five-minute exposures to HUT and HDT at angles of 5, 10, and 20 degrees. Calf, rump and tail measurements were made in three squirrel monkeys at 10 and 20 degrees of HUT and HDT.

Sporicidal efficacy of hydrogen peroxide aerosol.

Because of its high sporicidal activity but low toxicity, hydrogen peroxide (H2O2) is a useful agent for gentle antimicrobial treatment of irritable goods. Above all to optimise practical aspects of H2O2 application, sporicidal efficacy of aerosols based on 1% H2O2 solution was tested. Using commercially available bioindicators with Bacillus subtilis spores immobilized on filter paper strips, a 7 h lasting aerosol treatment at room temperature resulted in a reduction of viable count of 2.

Immunohistochemical localization of substance P and enkephalin in the nucleus tractus solitarii of the rhesus monkey, Macaca mulatta.

The nucleus tractus solitarii in the monkey Macaca mulatta was found to have several subdivisions based upon cytoarchitectonics and immunohistochemistry. Subdivisions that could be identified included commissural, medial, parvicellular, dorsolateral, ventrolateral, intermediate, and interstitial. Substance P and enkephalin immunoreactivity was localized within discrete regions of the nucleus tractus solitarii, by means of the peroxidase-antiperoxidase technique.

Automation of a fluorometric method for the determination of 2-deoxy-D-glucose.

A continuous-flow fluorometric procedure for the determination of 2-deoxy-D-glucose (2DG) is described. The method utilizes Technicon Autoanalyzer equipment and modules, and is based on the acid-catalyzed condensation of 3,5-diaminobenzoic acid with 2DG. The procedure permits analysis of 20 samples/h, is sensitive to concentrations of 2DG as low as 0.

Growth and maturation of mandibular bone in otherwise totally immobilized rhesus monkeys.

The effects of 14 days of total postcranial body immobilization (in plaster casts) on the mineralization rate and on the maturation of matrix and mineral moieties in the rhesus jaw were studied by tetracycline labeling and by density gradient methods, respectively. Immobilization did not alter the rates of periosteal and endosteal mineralization in the dense cortical bone from the lingular region of the jaw, but it did impair mineralization in osteonal bone. Osteons that continued to show radial closure did so at a normal rate.

The effect of protracted tetracycline treatment on bone growth and maturation.

Mature female rhesus monkeys were used to evaluate the effects of a one-year course of tetracycline (50 mg/kg/day, intramuscularly) on the formation, maturation, and mineralization of mandibular bone. The bones from the treated group contained normal concentrations of calcium (Ca), inorganic phosphorus (Pi), and hydroxyproline (HO-Pr), and the treatment schedule did not alter the distribution (percentage) of total osteons into slightly, moderately, and highly mineralization classes. Tetracycline impairs bone mineralization and the subsequent maturation of the mineral and matrix moieties.

Correlates of maximal oxygen consumption during treadmill exercise.

According to the Balke treadmill protocol, 39 healthy male USAF volunteers were subjected to maximal exercise. The subjects as a group passed the anaerobic threshold by the end of exercise since average venous lactate concentrations increased from 11.2 +/- 1.

Serum myocardial enzymes after +Gz acceleration.

Circulating levels of lactate dehydrogenase, glutamate-oxaloacetate, glutamate-pyruvate transaminase, and creatine phosphokinase, as well as its isoenzymes, were measured to investigate the possibility of myocardial damage during acceleration to high +Gz. Serum samples were analyzed in 12 human volunteers before, 6 h after, and 24 h after several bouts of accleration to 6, 8, 9, and 10 G. No substantial elevations of enzyme activities were observed.