Acute mountain sickness ( AMS) is defined as the syndromes which are induced by hypobaric hypoxia within a few hours or days of acute exposure to >2500 m or ascent to a higher altitude than residence .AMS poses a threat to the health and work capability of workers and tourists , as more people enter Tibet and other plateau areas in China .It is known that the incidence of AMS is higher among males and youths than among females , elders and children .The development of AMS is considered to be influenced by the level of sex hormones .Thus, there is the need to find more about the pathogene-sis, pathophysiology of AMS in order to treat and prevention of AMS by studying the relationship between sex hormones and AMS.

Objective To investigate the effect of plasma erythropoietin ( EPO) concentration on left ventricular systolic function and its relationship with acute mountain sickness ( AMS ) .Methods A total of 289 healthy young men were recruited in this study and divided into five groups:plain control group (Ⅰ) with 55 subjects;acute high altitude exposure group(Ⅱ) with 74 subjects(3700 m exposure for 24 h); the group of acute exposure after acclimatization (Ⅲ) with 68 subjects(4400 m exposure for 24 h after 1 week acclimatization at 3700 m); high altitude migrate group (Ⅳ) with 19 subjects ( migration to 3700 m for more than 1 year ); and the group of exposure after migration (Ⅴ) with 73 subjects (4400 m exposure for 50 d after more than one year migration to 3700 m).Lake Louise Self-assessment Scoring System ( LLSS) was used to assess AMS .Plasma concentrations of EPO and echocardiography were also determined .Results EPO was significantly increased after acute high altitude exposure .There was no significant difference in EPO between groupⅡand Ⅲ(P>0.05), but significantly higher than in group Ⅰ (P<0.05).No significant difference was found between group Ⅳ,Ⅴ and Ⅰ (P>0.05).In group Ⅱ, positive correlation was found between EPO concentration and stroke volume (SV) as well as left ventricular diastolic diameter (LVDD) (R=0.278 and 0.236,respectively,P<0.05), while negative correlation was expressed between EPO concentration and the AMS score (R=-0.249,P<0.05).In other groups,there was no relationship between EPO concentration and the index of left ventricular function .Conclusion EPO may work on AMS through left ventricular systolic function enhancement after acute high altitude exposure .

Objective To explore that whether the normoxic low altitude measurement of arterial blood pressure would predict subsequent susceptibility to acute mountain sickness ( AMS) during rapid ascent to high altitude .Methods Arterial blood pressure ( using a wrist sphygmomanometer ) was determined in two hundred and four healthy lowlanders first exposed to 3700 m-altitude (Lhasa) from plain (500 m) by air, and the Lake Louise self-report questionnaire(LLS) was used to assess AMS.We compared the low altitude blood pressure related indicators of two groups ( AMS and non-AMS ) and analyzed the relationship of diagnostic score and blood pressure related indicators .Results ①The incidence of AMS in the selected subjects was 53.92% by LLS.AMS scores increased markedly at high-altitude (P<0.05 versus low altitude).②Diastolic blood pressure (DBP) and mean arterial BP (MABP) in the AMS group were higher than those in the non-AMS group(P<0.05).The low altitude DBP levels for diagnosis of AMS at high-altitude (3700 m) had an area under curve(AUC) =0.598, P<0.05, with sensitivity of 56.3%, specificity of 63.2%, and cut-off point of 72.5 mmHg. Conclusion ①After acute exposure to high altitude , the incidence of AMS increases significantly .②A higher baseline DBP may be considered a potential risk factor for AMS , and is positively associated with LLS .DBP may serve as a predic-tive parameter for diagnosis of AMS .However , the clinical application of DBP as a predictive criterion is limited because of its poor specificity or sensitivity .The use of DBP as a predictive criterion should be combined with other indicators for the better predictive value of AMS .

Objective: To evaluate the efficacy and safety of catheter-directed interventional therapy in patients with acute pulmonary embolism(PE). Methods: PE was diagnosed by CT pulmonary angiography(CTPA). After risk stratification, a total of 79 PE patients (age (58.9±14.9) years old)were treated with catheter-directed interventional therapy via pulmonary vessels. The changes of pulmonary hemodynamics were compared before and after treatment. The risk of complications and side effects were observed. Results: The pulmonary artery pressure was changed followed by interventional therapy. The interventional therapy significantly decreased mean pulmonary arterial pressure (mPAP) from (35.3±11.2)mmHg (1 mmHg=0.133 kPa) to (30.0±10.6)mmHg (t=8.803,P<0.05) and the echocardiographic derived right ventricular dimension to left ventricular dimension (RV/LV) ratio from 0.93±0.16 to 0.83±0.15 (t=6.868,P<0.05). The arterial partial pressure of oxygen was increased from (69.0±8.6)mmHg to (75.1±9.9)mmHg (t=8.561,P<0.05) . The oxygen saturation was also increased from (93.9±2.9)% to (95.1±1.9)% at 24 h after the treatment (t=2.621,P<0.05) . Patients were further grouped as high-risk group (n=28) and intermediate risk group (n=51). mPAP and RV/LV ratio were significantly reduced in the two subgroups (all P<0.05) and the range of reduction was more significant in the high-risk group. Five patients experienced minor bleeding complication, 3 patients suffered worsened dispone post procedure and were treated with mechanical ventilation, 1 patient died, and 1 patient developed recurrent PE. Conclusion The catheter-directed interventional therapy improves pulmonary hemodynamics and reduces load of right ventricle both in high-risk or intermediate risk PE patients, this therapy strategy is safe and effective for patients with PE.