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1.
Fundam Appl Toxicol ; 20(2): 240-7, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8449396

ABSTRACT

Performance and physiological measurements were obtained from four pairs of men exposed for 24 hr to 1% (10,000 ppm) Halon 1301 (bromotrifluoromethane, CBrF3) and to air with order counterbalanced using a double-blind protocol. Cognitive and motor performance was assessed before, during, and after the exposures using seven scales of the Automated Portable Testing System, which produced 13 measures of performance. Halon inhalation induced decrements in 2 of the 13 measures, but actual and estimated magnitudes of the decrements were no greater than 5% of baseline values. Physiological data were obtained before, during, and after the exposures from clinical chemistry analyses of blood and urine samples, pulmonary function tests, and monitoring of vital signs. Significant change during Halon inhalation was observed for 6 of the 52 variables assessed; however, all physiological values remained within clinically acceptable limits. No cardiovascular effects were noted. This study demonstrated that exposure to 1% Halon 1301 for 24 hr can produce minor disturbance of central nervous system function as assessed by cognitive tasks.


Subject(s)
Chlorofluorocarbons, Methane/toxicity , Psychomotor Performance/drug effects , Psychomotor Performance/physiology , Administration, Inhalation , Adult , Blood Urea Nitrogen , Bromochlorofluorocarbons , Forced Expiratory Volume/drug effects , Humans , Lymphocytes/drug effects , Male , Neutrophils/drug effects , Prothrombin Time , Psychological Tests , Time Factors , Uric Acid/metabolism
2.
J Interferon Res ; 12(2): 75-81, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1578189

ABSTRACT

A 27-year-old woman was maintained in an isolated state for 131 days in Carlsbad Caverns, New Mexico. Her diet was vitamin D-depleted. Determinations on the effects of such isolation on levels and activities of peripheral blood cells that are important for hematological homeostasis and immunological function were carried out. Throughout the duration of the study, the percentage of lymphoid cells that expressed CD3, CD4, CD8, CD19, Leu 8, and other markers remained relatively constant although the absolute numbers of these cells varied. Although the percentage of natural killer (NK) cells did not vary, the activity of these cells did change. NK cell activity became elevated as the isolation study progressed. Production of interferon-gamma (IFN-gamma) in response to mitogen stimulation was higher than expected throughout the isolation periods, but returned to the normal range after termination of the isolation. Red and white cell counts dropped significantly upon entering isolation, but soon returned to normal.


Subject(s)
Blood Cell Count , Interferon-gamma/biosynthesis , Leukocytes/immunology , Social Isolation , Adult , Erythrocyte Count , Female , Humans , Killer Cells, Natural/immunology , Leukocyte Count , Platelet Count
3.
Aviat Space Environ Med ; 63(1): 46-51, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1550533

ABSTRACT

Treatment of acute motion sickness induced by parabolic flight with a preparation of scopolamine placed in the buccal pouch was investigated. Twenty-one subjects flew aboard a KC-135 aircraft operated by the National Aeronautics and Space Administration (NASA) which performed parabolic maneuvers resulting in periods of 0-g, 1-g, and 1.8-g. Each subject flew once with a tablet containing scopolamine and once with a placebo in a random order, crossover design. Signs and symptoms of motion sickness were systematically recorded during each parabola by an investigator who was blind to the content of the tablet. Compared with flights using placebo, flights with buccal scopolamine resulted in significantly lower scores for nausea (31%-35% reduction) and vomiting (50% reduction in number of parabolas with vomiting). Side effects of the drug during flight were negligible. We conclude that buccal scopolamine is more effective than a placebo in treating ongoing motion sickness.


Subject(s)
Motion Sickness/drug therapy , Scopolamine/therapeutic use , Space Flight , Administration, Buccal , Adult , Humans , Male , Middle Aged , Nausea , Placebos , Scopolamine/administration & dosage , Scopolamine/pharmacokinetics , Vomiting
4.
Aviat Space Environ Med ; 54(11): 994-1000, 1983 Nov.
Article in English | MEDLINE | ID: mdl-6651736

ABSTRACT

This study evaluated the time course of efficacy of transdermal scopolamine in the prevention of motion sickness induced by exposure to coriolis stimulation in a rotating chair. We measured levels of efficacy, quantified side effects and symptoms, and determined inter- and intra-subject variability following use of transdermal scopolamine. The response to transdermal scopolamine was highly variable, although overall we recorded a 40% improvement (p less than 0.05) in test scores 16-72 h after application of the transdermal system. This variability could not be explained solely by the levels of scopolamine present in the blood. The improvement was not due to the artifactual repression by scopolamine of selected symptoms of motion sickness. An unexpectedly high incidence of side effects was reported. It was concluded that the therapeutic use of transdermal scopolamine be evaluated individually and that individuals be cautioned that subsequent usage may not always be effective.


Subject(s)
Motion Sickness/prevention & control , Scopolamine/therapeutic use , Administration, Topical , Delayed-Action Preparations , Female , Humans , Male , Scopolamine/administration & dosage , Scopolamine/adverse effects , Time Factors
5.
Aviat Space Environ Med ; 51(11): 1209-13, 1980 Nov.
Article in English | MEDLINE | ID: mdl-7213266

ABSTRACT

The os calcis mineral was measured in the nine Skylab crew members and in eight control subjects, 5 years after the Skylab Program, utilizing a photon absorptiometric technique. These measurements were compared with preflight measurements in an attempt to discover any long-term effects of space flight on the skeletal system. A statistically significant loss of bone mineral was found in the crew members who flew, but caution is urged in the interpretation of this difference. A recommendation to continue studies of this type is made.


Subject(s)
Aerospace Medicine , Osteoporosis/etiology , Calcaneus/diagnostic imaging , Follow-Up Studies , Humans , Male , Middle Aged , Radionuclide Imaging , Space Flight , Weightlessness/adverse effects
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