Early Warning of Acute Altitude Sickness by Physiological Variables and Noninvasive Cardiovascular Indicators / 中国医学科学杂志(英文版)

Objective To examine if the variations at sea level would be able to predict subsequent susceptibility to acute altitude sickness in subjects upon a rapid ascent to high altitude. Methods One hundred and six Han nationality male individuals were recruited to this research. Dynamic electrocardiogram, treadmill exercise test, echocardiography, routine blood examination and biochemical analysis were performed when subjects at sea level and entering the plateau respectively. Then multiple regression analysis was performed to construct a multiple linear regression equation using the Lake Louise Score as dependent variable to predict the risk factors at sea level related to acute mountain sickness (AMS). Results Approximately 49.05% of the individuals developed AMS. The tricuspid annular plane systolic excursion (22.0±2.66 vs. 23.2±3.19 mm, t=1.998, P=0.048) was significantly lower in the AMS group at sea level, while count of eosinophil [(0.264±0.393)×109/L vs. (0.126±0.084)×109/L, t=-2.040, P=0.045], percentage of differences exceeding 50 ms between adjacent normal number of intervals (PNN50, 9.66%±5.40% vs. 6.98%±5.66%, t=-2.229, P=0.028) and heart rate variability triangle index (57.1±16.1 vs. 50.6±12.7, t=-2.271, P=0.025) were significantly higher. After acute exposure to high altitude, C-reactive protein (0.098±0.103 vs. 0.062±0.045 g/L, t=-2.132, P=0.037), aspartate aminotransferase (19.7±6.72 vs. 17.3±3.95 U/L, t=-2.231, P=0.028) and creatinine (85.1±12.9 vs. 77.7±11.2 mmol/L, t=-3.162, P=0.002) were significantly higher in the AMS group, while alkaline phosphatase (71.7±18.2 vs. 80.6±20.2 U/L, t=2.389, P=0.019), standard deviation of normal-to-normal RR intervals (126.5±35.9 vs. 143.3±36.4 ms, t=2.320, P=0.022), ejection time (276.9±50.8 vs. 313.8±48.9 ms, t=3.641, P=0.001) and heart rate variability triangle index (37.1±12.9 vs. 41.9±11.1, t=2.020, P=0.047) were significantly lower. Using the Lake Louise Score as the dependent variable, prediction equation were established to estimate AMS: Lake Louise Score=3.783+0.281×eosinophil-0.219×alkaline phosphatase+0.032×PNN50. Conclusions We elucidated the differences of physiological variables as well as noninvasive cardiovascular indicators for subjects after high altitude exposure compared with those at sea level. We also created an acute high altitude reaction early warning equation based on the physiological variables and noninvasive cardiovascular indicators at sea level.

Physiological Variables Associated with the Development of Acute Mountain Sickness / 中国医学科学杂志(英文版)

Objective To identify the physiological variables associated with the development of acute mountain sickness (AMS). Methods Eighty four young Chinese men residing at low altitude were taken to an altitude of 4000 m within 40 hours. At sea level and at high altitude, we measured the heart rate, blood pressure, and peripheral oxygen saturation (SpO2) respectively. We also collect blood samples from each participants before and after the altitude elevation. The blood routine and biochemical examinations were performed for all blood samples. The revised Lake Louise Criteria was adopted to diagnose AMS after the subjects arrived at the target high altitude. The association between the presence of AMS and subjects' physiological variables were analysed statistically. Results Of 84 participants, 34 (40.5%) developed AMS. Compared with non AMS group, in the AMS group, the percentage of neutrophils was significantly higher (64.5%±11.2% vs. 58.1%±8.8%, P =0.014), while the level of SpO2 was significantly lower (79.4%±5.4% vs. 82.7%±5.6, P=0.008). Binary logistic regression analyses emphasized the association of neutrophils (OR: 1.06, 95% CI: 1.01-1.12, P=0.034) and SpO2 level (OR: 0.87, 95% CI : 0.79-0.95, P=0.004) with the development of AMS. Conclusion The ability to sustain SpO2 after altitude elevation and the increase of neutrophils were associated with the development of AMS in young males.

Mutation Analysis of CIB2 196C＞T 272T＞C and 297C＞G in Patients with Non-syndromic Hearing Impairment / 昆明医科大学学报

Objective To investigate the gene mutations of calcium-and integrin-binding protein 2 (CIB2) 196C＞T, 272T ＞ C and 297C ＞ G carried by students with non-syndromic hearing impairment from special educational schools in Yunnan Province. Methods The experimental group included 337 students with non-syndromic hearing impairment who failed to carry deafness gene with GJB2 (35 del G, 176_191 del 16,235delC, 299_300 del AT), GJB3 (C538T,G547A), mtDNA 12S rRNA (A1555G, C1494T), and SLC26A4 (IVS7_2A＞G, A2168G) . The control group consisted with 150 healthy people. Genomic DNA was isolated from peripheral blood with EDTA anti-coagulate. The subject's DNA fragments including CIB2 196C＞T, 272T ＞ C and 297C＞ G were amplified by polymerase chain reaction (PCR), and subsequently analyzed by direct sequencing to identify deafness-associated mutations. Results Both in the experimental group and control group, we failed to find the mutation of CIB2 196C＞T, 272T＞C and 297C＞G in all individuals. Conclusion Mutations in CIB2 gene 196C＞T, 272T＞C and 297C＞G are not a frequent cause of non-syndromic hearing loss among deaf people in Yunnan province. It provided important information for deafness with formulating landscape of gene screening in this region.

Effects of treadmill exercise on central hemodynamics in patients below 60 years of age with coronary artery disease / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of treadmill exercise on central hemodynamics in patients with coronary artery disease.</p><p><b>METHODS</b>Sixty-eight consecutive patients below 60 years of age with the diagnosis of coronary artery disease (CAD) between July, 2013 and April, 2014 underwent treadmill exercise test following the standard Bruce protocol. Ninety-seven individuals without CAD served as the control group. Central hemodynamics of the subjects, including the central aortic blood pressure (cSBP), augmentation index (AI) and augmentation pressure (AP), were examined before and after the exercise.</p><p><b>RESULTS</b>cSBP increased significantly after acute exercise in both groups (P<0.001). Immediately after treadmill exercise, AI showed no significant changes in CAD patients (P=0.561) but decreased significantly in the control subjects (P<0.001). AI before exercise and cSBP after exercise were significantly higher in CAD group than in the control group (P=0.009 and 0.009, respectively). Stepwise regression analysis showed that the maximal heart rate after exercise was the main factor that affected cSBP increment in CAD group (P=0.012), and the occurrence of ischemia after exercise was associated with a lower cSBP increment (P=0.048).</p><p><b>CONCLUSION</b>AI does not decrease significantly after acute exercise in patients with CAD, suggesting that AI is closely associated with coronary artery blood perfusion after exercise and may serve as a potential target for improving ischemic threshold during rehabilitation of the patients.</p>

Establishment of B lymphoblastoid cell lines of Miao pedigree with Bardet-Biedl syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To establish immortalized lymphoblastoid cell lines of a Miao core pedigree with Bardet-Biedl syndrome (BBS), in order to provide a long-term source of material for research.</p><p><b>METHODS</b>With Epstein-Barr virus transformation of B cells and addition of cyclosporine A to inhibit the activity of T cells, fresh anticoagulated blood samples with heparin were collected from 12 members of the core pedigree, and were used to establish the immortalized lymphoblastoid cell lines of B lymphocytes.</p><p><b>RESULTS</b>Twelve immortalized lymphoblastoid cell lines of the core BBS pedigree were obtained successfully.</p><p><b>CONCLUSION</b>The immortalized B lymphoblastoid cell lines of the Miao pedigree with BBS can preserve the whole genome information and provide long-term research materials for BBS study.</p>