Role of oxygen therapy in prevention of chronic mountain sickness / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To explore the effect of prophylaxis on youth's chronic mountain sickness(CMS) who moved to an altitude of above 5 000 meters by long-term oxygen therapy (LTOT).</p><p><b>METHODS</b>Ninety-six male youth stationed at 5 070 m, 5 200 m and 5 380 m took oxygen continuously by nasal cannula (LTOT group) every body per day. One year later, epidemiological survey were carried out according to the international CMS diagnostic criteria consist of examining right ventricle end-diastolic dimension (RVED), right ventricular anterior wall (RVAW), right ventricular outflow tract (RVOT), main pulmonary artery (MPA), left ventricular end systolic diameter (LVSD) by ultrasonic diagnostic apparatus, and blood test of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (gamma-GT), creatine kinase (CK), lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide (NO), nitric-oxide synthase (NOS) blood oxygen saturation (SaQ2). Then, they were compared with 91 males in the same group stationed at the same altitude (without any interventions, control group).</p><p><b>RESULTS</b>(1) The epidemiological survey showed that, SaO2 were increased significantly (P < 0.05) and the prevalence rate of CMS were decreased compared with that of control group (P < 0.05). (2) Echocardiography showed that SOD, NO, NOS were increased (P < 0.05 or 0.01) and LVSD, MPA had no significant difference compared with that of control group (P > 0.05). (3) Biochemical index showed that, SOD, NO, NOS were increased (P < 0.05 or 0.01), MDA, ALT, AST, LDH were decreased (P < 0.05 or 0.01) and gamma-GT, CK had no significant difference compared with that of the control group.</p><p><b>CONCLUSION</b>At high altitude, LTOT can reduce lipid peroxidation, improve the important organ injuries caused by hypoxia and protect the mitochondria respiratory function and play an important role on the prevention of chronic mountain sickness.</p>

Effect of iptkalim on myocardial enzymes and free radicals metabolism with hypoxic pulmonary hypertension / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To explore the effects of iptkalim on myocardial enzymes and free radicals metabolism with hypoxic pulmonary hypertension (HPH), in order to provide evidence for the mechanism of iptkalim on clinical treat.</p><p><b>METHODS</b>110 young men stayed at high altitude above 5 000 m were divided into iptkalim group (n = 74) and placebo group (n = 36), aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase (gamma-GT), creatine kinase (CK), lactate dehydrogenase (LDH), superoxide dismutase (SOD), malonaldehyde (MDA), nitric oxide(NO) and nitric oxide synthase(NOS) were detected before and after took medicines for 6 mouths.</p><p><b>RESULTS</b>After took medication for 6 mouths, ALT, AST, gamma-GT, CK and LDH were reduced, SOD, NO, and NOS were increased, MDA were reduced, there were very significant difference (P < 0.05).</p><p><b>CONCLUSION</b>Oxygen free radicals have taken part in the process of HPH, iptkalim have the effect of anti-peroxidation of lipid and protect myocardial cells stress injured by hypoxia which related with mitochondrial membrane and cell membrane's K(ATP) channel activation.</p>

Sperm DNA damage in young men working on the plateau / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate whether long working in the high-altitude area can damage sperm DNA in men.</p><p><b>METHODS</b>We enlisted 51 service men stationed on the plateau in an observation group and another 53 living in the low-altitude area in a control group. We detected and compared the damages to sperm DNA in the semen samples from the two groups using single cell gel electrophoresis and the sperm chromatin dispersion test.</p><p><b>RESULTS</b>The percentages of total, G1, G2 and G3 comet cells and abnormal sperm of the observation group were (5.56 +/- 3.98)%, (3.72 +/- 1.85)%, (1.57 +/- 1.07)%, (0.27 +/- 0.34)% and (16.59 +/- 12.07)%, respectively, before stationed on the plateau, but significantly increased at 6 months of plateau life ([11.15 +/- 8.59]%, [5.97 +/- 3.26]%, [3.83 +/- 2.13%, [1.35 +/- 1.53]% and [22.03 +/- 15.33]%, P<0.05). The percentages of G2 comet cells and abnormal sperm were decreased to (3.32 +/- 1.83)% and (20.54 +/- 15.52)% at 12 months, but still significantly higher than the baseline (P<0.05).</p><p><b>CONCLUSION</b>Long working on the plateau may damage sperm DNA, but its influence on male fertility deserves further investigation. Therefore, it is important to reinforce reproductive health protection for males working on the plateau.</p>

Changes of VEGF, TNF-alpha, IL-6 and NO in serum of patients with HAPE / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To explore the possible pathophysiological process and mechanisms underlying the development and formation of high altitude pulmonary edema(HAPE) by observing the changes in contents of VEGF, TNF-alpha, IL-6 and NO in serum from the initiated and recovery of HAPE patients.</p><p><b>METHODS</b>We studied 10 HAPE patients in a Chinese population. The patients were divided into two groups including HAPE initiate group and the recovery group. Contents of VEGF, TNF-alpha, IL-6 and NO in serum of the two groups were determined to study the process of HAPE.</p><p><b>RESULTS</b>VEGF levels in the HAPE initiate one and the recovery groups were (167.9 +/- 26.5 and 53.1 +/- 17.0 pg/ ml), respectively. There was a significant decrease of VEGF content in recovery one compared to the HAPE group. The same results for TNF-alpha were gained. The levels of TNF-alpha in recovery group was much lower than that in the HAPE initiate one. They were (29.2 +/- 6.8) pg/ml and (86.2 +/- 24.1) pg/ml, respectively. The contents of IL-6 in HAPE initiate group and the recovery group were (32.3 +/- 16.5) pg/ml and (12. 5 +/- 8.0) pg/ml, respectively. But no significance existed. The level of NO in HAPE initiate group was (33.8 +/- 3.3) micromol/L, and it remarkably increased to (74.1 +/- 6.2) micromol/L in recovery one.</p><p><b>CONCLUSION</b>VEGF, TNF-alpha, IL-6 and NO participated in the different aspects of the pathophysiological process and might have influence on HAPE.</p>

Protective effects of new compound codonopsis tablets against acute mountain sickness / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To study on the protective effects of new compound codonopsis tablets against acute mountain sickness (AMS).</p><p><b>METHODS</b>Forty-five male plain resident soldiers stayed at 1400 m altitude for 3 months were randomly divided into two groups, control (15 men) and treatment group (30 men). Single blind trial was used in this study. The subjects in the two groups took placebo and new compound codonopsis tablets respectively for 5 days before climbing to high mountain, and continued to take for another 10 days until the 3rd day after arriving at 5200 m altitude. On the 1st , 3rd, and 5th day after they arrived at 5200 m altitude, the score and the degree of AMS symptoms of soldiers were followed up and recorded according to State Military Standard GJB1098-91--"Principles of diagnosis and treatment of benign form of acute mountain sickness", heart rate (beats/min) and arterial oxygen saturation (%) were detenrmined. On the 6th day after they arrived at high altitude, forced vital capacity(FVC), forced expired volume in one second(FEV1.0), FEV1% (FEV1.0/FVC), FEF25%-75%, peak expiratory flow (PEF) and maximal voluntary ventilation (MVV) were detected, total frequency of hands cross movement and memory of order numbers test were measured.</p><p><b>RESULTS</b>Comparison with control, AMS symptoms of treatment group reduced on the 1st, 3rd, and 5th day after arriving at 5200 m high altitude (P < 0.01). The degree of AMS symptoms of treatment group was significantly different from that of control. The proportion of slight symptoms in treatment group was high, and that of relative serious symptoms in control was high. Compared with control, FVC, FEV1.0, FEF25%-75%, PEF and MVV of treatment group increased (P < 0.05, P < 0.01), and Ttis, Ctis of treatment group increased (P < 0.05, P < 0.01), Atime decreased markedly (P < 0.05), there was no statistically significant difference in Etis and Sum between the two groups.</p><p><b>CONCLUSION</b>New compound codonopsis tablets could decrease the incidence of AMS, mitigate the symptoms of AMS, and improve breathing function and fingers movement function. New compound codonopsis tablets have an obvious effect on prevention and treatment of acute mountain sickness.</p>

Investigation of hyperbaric oxygen preconditioning on anoxic resistance and anti-weariness at high altitude / 中国应用生理学杂志

<p><b>AIM</b>To explore the influence of hyperbaric oxygen (HBO) preconditioning on anoxic resistance and anti-weariness at high altitude.</p><p><b>METHODS</b>(1) SOD, MDA, NO, NOS, BLA and BUN of 20 youths living at 3 700 m altitude for half year were tested, then they were divided into group A (n=10, received HBO pretreatment twice) and group B (n=10, received HBO pretreatment 5 times) randomly. They were asked to pedal the EMG-bicycle-ergometer at the second and eighth day, and then the same items were tested. (2) 29 youth who would go to Astronomical Spot (5200 m) were randomly divided into group HBO (n=11, received HBO pretreatment once per day for 2 days at Yecheng (1400 m)) and comparison group (n=10). When they reached I Astronomical Spot, thematic biochemical index were investigated. (3) When 20 youth reached Thirty Milepost Barracks (3700 m) at the second day in their way to Immortal Gulf (5380 m) from Yecheng were randomly divided into group HBO (n=10, received HBO pretreatment once per day for 3 days) and comparison group (n=10). When they reached Immortal Gulf, the thematic biochemical index were investigated.</p><p><b>RESULTS</b>(1) SOD, NO, NOS were increased and BLA, BUN, MDA were decrease in group A compared with that in group B until the eighth day, there was significant difference (P < 0.01). (2) SOD, NO, NOS were increased and BLA, BUN, MDA were decrease in group HBO compared with that in comparison that in group, there was significant difference between groups (P < 0.01, or P < 0.05).</p><p><b>CONCLUSION</b>HBO could enhance the activity of anti-oxidase and the cleared ability of lactic acid, and the effect of anti-weariness could last for 8 days.</p>

Intervention of nutritional status and hypoxia endurance by a nutritional supplement in young adults living at high altitude / 中国应用生理学杂志

<p><b>AIM</b>To investigate the effects of a nutritional supplement on nutritional status and hypoxia endurance in young adults living at high altitude.</p><p><b>METHODS</b>Forty healthy male young adults were recruited and randomly assigned to control and intervention groups. The nutrition survey was carried out using weighing method. The intervention group was given a nutritional supplement specifically designed for use at high altitude, while the control group was treated with a supplement made of stir-fried flour. After 20 days of supplementation, they marched from the altitude of 3700 m to 5100 m. The changes in HR, SaO2, serum concentrations of VA and VB2 and some minerals were measured.</p><p><b>RESULTS</b>The results of nutrition survey showed that the ratio of three macronutrients was not adequate and the intakes of calcium, VA and VB2 were below Chinese RNI. The serum concentrations of calcium, magnesium and VA were below normal references. The serum VB2 concentration was at the low level o f normal reference. The nutritional supplement could increase the serum concentrations of calcium, magnesium, VA and VB2, indicating an improved nutritional status. The changes in HR and SaO2 were diminished in intervention group compared with control group.</p><p><b>CONCLUSION</b>The nutritional supplement can improve nutritional status and increase the hypoxia endurance in young adults living at high altitude.</p>

Studies on immunoregulation of polysaccharides-la from Radix Cynanchi Bungei / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effects of PRCB1a (one component of polysaccharides from Radix Cynanchi Bungei) on transformation of T lymphocytes of rabbit in vitro and immune function in mice.</p><p><b>METHOD</b>Three doses of PRCB1a (2,4,6 g x L(-1)) were respectively put in bottle with PHA and blood of rabbit. The effect of PRCB1a on immunity in vitro was studied by observing transformation of T lymphocytes; The dosage of PRCB1a (50,100,150 mg x kg(-1) x d(-1)) was given orally for seven days. The effects on immune function were investigated in mice.</p><p><b>RESULT</b>Three doses of PRCB1a could significantly promote (P < 0.01) the ability of T lymphocytes proliferation; PRCB1a could improve the mouse thymus and spleen index, the celiac macrophage ability of engulfing CRBC, the delayed type hypersensitivity ability and the macrophage engulfing carbon granula ability.</p><p><b>CONCLUSION</b>The results indicate PRCB1a can enhance nonspectific and specific cellular immune function.</p>