Objective To explore the risk factors for nocturnal hypoxemia in patients with ob-structive sleep apnea(OSA)and construct an assessment model.Methods A total of 303 patients with OSA diagnosed by polysomnography(PSG)were selected as research objects.Based on PSG re-sults,they were divided into case group(171 patients with hypoxemia)and control group(132 pa-tients without hypoxemia).Materials were compared between the two groups;multivariable Logistic re-gression analysis was used to screen risk factors for nocturnal hypoxemia in OSA patients and construct a risk assessment model.Value of the model was evaluated by the area under the curve(AUC)of the receiver operating characteristic(ROC)curve and K-fold cross-validation.Results The case group had significantly higher values in age,body mass index(BMI),neck circumference,proportion of smokers,hemoglobin,red cell distribution width(RDW),apnea-hypopnea index(AHI),the longest apnea duration(LAD),snoring index,and percentage of apnea-hypopnea duration to total sleep time(AHT％)when compared to the control group(P＜0.05).Logistic regression analysis showed that high BMI,high RDW,long LAD,and high AHT％were risk factors for nocturnal hypoxemia in OSA patients(P＜0.05).AUC value(0.952)of the ROC curve of the assessment model constructed based on these factors was higher than the AUC values of BMI(0.833),RDW(0.780),LAD(0.866),and AHT％(0.898)alone.One hundred times of 10-fold cross-validation demonstrated that the assessment model had good generalization ability.Conclusion Nocturnal hypoxemia in OSA patients is associated with high BMI,high RDW,long LAD,and high AHT％.The model constructed based on these factors plays an important role in evaluating nocturnal hypoxemia in OSA patients.

AIM:To investigate the impact of Kir2.1 channels on abnormal spontaneous pacemaker activities induced by hypokalemia and to elucidate the underlying mechanisms.METHODS:Human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs)were transfected with lentiviral particles containing sequences for human Kir2.1,the Kir2.1-E224G mutant,or Kir4.1.Patch clamp techniques were employed to examine the effects of low extracellular potassium concentration([K+]e)of 1 mmol/L on the resting membrane potentials and whole-cell currents of the cells in each group,assessed via both current and voltage clamp modes.RESULTS:Under conditions of 1 mmol/L[K+]e,cur-rent clamp data revealed that hiPSC-CMs overexpressing Kir2.1 channels exhibited both hyperpolarized and depolarized resting membrane potentials,with the depolarized state triggering abnormal pacemaker activities.In contrast,cells overex-pressing the Kir2.1-E224G mutant or Kir4.1 channels displayed only hyperpolarized resting membrane potentials.Voltage clamp analysis indicated that hiPSC-CMs overexpressing Kir2.1 channels produced"N"-shaped whole-cell currents,whereas cells expressing the Kir2.1-E224G mutant or Kir4.1 exhibited typical K+currents.CONCLUSION:Kir2.1 channels play a crucial role in mediating hypokalemia-induced abnormal spontaneous pacemaker activities in human car-diomyocytes through their inward rectification properties.

AIM:To investigate the impact of Kir2.1 channels on abnormal spontaneous pacemaker activities induced by hypokalemia and to elucidate the underlying mechanisms.METHODS:Human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs)were transfected with lentiviral particles containing sequences for human Kir2.1,the Kir2.1-E224G mutant,or Kir4.1.Patch clamp techniques were employed to examine the effects of low extracellular potassium concentration([K+]e)of 1 mmol/L on the resting membrane potentials and whole-cell currents of the cells in each group,assessed via both current and voltage clamp modes.RESULTS:Under conditions of 1 mmol/L[K+]e,cur-rent clamp data revealed that hiPSC-CMs overexpressing Kir2.1 channels exhibited both hyperpolarized and depolarized resting membrane potentials,with the depolarized state triggering abnormal pacemaker activities.In contrast,cells overex-pressing the Kir2.1-E224G mutant or Kir4.1 channels displayed only hyperpolarized resting membrane potentials.Voltage clamp analysis indicated that hiPSC-CMs overexpressing Kir2.1 channels produced"N"-shaped whole-cell currents,whereas cells expressing the Kir2.1-E224G mutant or Kir4.1 exhibited typical K+currents.CONCLUSION:Kir2.1 channels play a crucial role in mediating hypokalemia-induced abnormal spontaneous pacemaker activities in human car-diomyocytes through their inward rectification properties.

Abstract In recent years, mental health problems such as anxiety and depression among adolescents in China have attracted attention from all walks of life. Given that adolescence is a transitional and critical period for individual development, mental health affect the developmental opportunities. Therefore, in the review, the effects of environment, psychosocial factors and behavioral patterns on depressive symptoms are analyzed by combining with the characteristics of physical and mental development among adolescents. It is found that early adolescence and even childhood should be the key period for the prevention and intervention of depression. In order to formulate effective interventions and prevention strategies, it is proposed that future research should combine real situation in China with active exploration of protective factors and early predictors of depression.

Objective: To explore age, gender, and regional differences in physical activity among children and adolescents in China, and to provide a scientific reference for enhancing physical activity promotion. Methods: A total of 4 269 children and adolescents aged 7 to 18 years were selected from six administrative regions of China (East China, Northwest China, North China, Central China, Southwest China and South China) using a stratified random cluster sampling method from September to December 2018. A questionnaire was administered to evaluate the physical activity level of Chinese children and adolescents aged 7 to 18. Results: The overall detection rate of MVPA insufficiency in children and adolescents in China was 53.8%, of which the detection rate of MVPA insufficiency was 50.8% among boys and 57.1% among girls. Gender differences were statistically significant ( χ 2= 17.10 , P <0.05). Among the different age groups, the lowest detection rate of MVPA among 10-12 year olds was 43.6%, whereas the highest rate among 16-18 year olds was 63.0%, with significant differences between gender ( χ 2=4.33, 30.79, P <0.05). The P 50 values of total physical activity(TPA), light intensity physical activity(LPA), moderate intensity physical activity(MPA), vigorous intensity physical activity(VPA), moderate to vigorous physical activity(MVPA) were 92.9,24.3,41.4,7.1 and 55.7 min/d , respectively. The P 50 values of physical exercise, housework activities, entertainment activities and transportation activities were 34.3 , 2.1, 2.3 and 30.0 min/d, respectively, and the difference in age groups was statistically significant( H =95.03, 74.99, 300.26 , 64.16, P <0.05). There was a statistically significant difference in the detection rate of insufficient MVPA among children and adolescents in different regions ( χ 2=83.91, P <0.05). The lowest rate was 44.0% in North China, and the highest was 65.9% in East China. Conclusion The detection rate of MVPA insufficiency among Chinese children and adolescents firstly decreased and then increased with age. Boys participated in higher levels of physical activity than girls.

Objective: To explore the correlation between physical activity and nutritional status of Chinese children and adolescents, and to provide references for the healthy development of Chinese adolescents. Methods: According to the six administrative regions of China (East China, Northwest China, North China, Central China, Southwest China and South China), 4 269 children and adolescents aged 7 to 18 were selected by stratified random sampling method. "Physical Activity Level Evaluation Questionnaire" was used to conduct a physical activity survey. Chi square test and non parametric test were used to analyze the physical activity status. Results: The overall detection rate of MVPA insufficiency in children and adolescents with normal BMI were 53.7%, 50.2%, 56.3%, and 52.5% in the wasting group, overweight and obese group, respectively. There was no significant difference in the detection rate of MVPA insufficiency between different nutritional status( χ 2=2.55, P >0.05); but in the 7-9 years old age group, the difference in the detection rate of MVPA insufficiency between different nutritional status were statistically significant( χ 2= 10.35, 8.86, 15.88, P <0.05). There were no significant differences in physical activity intensity and item types under different nutritional status ( P >0.05). Conclusion There are age differences in the correlation between physical activity and nutritional status of children and adolescents in my country.Therefore, the differences between different groups should be fully considered while formulating intervention policies.

Objective: To analyze the correlation between physical activity and physical fitness index of children and adolescents in China, so as to provide reference for physical activity and physical fitness promtion of children and adolescents. Methods: In September 12,2018, 4 269 students were selected by cluster sampling in east, northwest, north, central, southwest and South China, the test of standing long jump, grip strength, 50 m running, improved seat forward bend, 30 s sit ups, 20 s cross repeatedly, 20 m round trip running was completed. Results: In comparing the physical fitness index of children and adolescents with different levels of physical activity, the PFI values of the middle and high intensity physical activity (MVPA) groups of boys aged 10-12 and 16-18 years old were (0.46±3.58) (0.75±3.0), the value of PFI of the MVPA group were (-0.69±3.64) (-0.61±2.87), the difference was statistically significant ( t =0.04, 0.57, P >0.05). There was no significant difference in the values of PFI between the four age groups of the girls ( P <0.05). In comparison of physical activity status of children and adolescents in different physical ability grades, the time of MPA, VPA and physical exercise in healthy physical ability group was higher than that in unhealthy physical ability group ( Z =-2.04, -4.93, -7.09, P <0.05). Linear regression analysis showed that there was a positive correlation between daily MVPA, physical exercise and physical fitness index ( P <0.05). Conclusion Moderate and high intensity physical activity, that is, physical exercise, is positively correlated with physical fitness index. Therefore, it is particularly important for children and adolescents to engage in sufficient moderate and vigorous intensity physical activities.

Objective To evaluate the effect of transurethral feedback microwave thermotherapy with the ProstaLund CoreTherm Device (PLFT) in benign prostate hyperplasia ( BPH ) patients with high risk factors 24 months after treatment.MethodsSixty-two BPH cases with high risk factors of aged ≥ 80or complicating severe conditions of no less than one organ or system,were treated with PLFT under urethral local anesthesia.The average pre-treatment prostate volume,international prostate symptom score (IPSS),quality of life score (QOL) and maximal urinary flow (Qmax) were 62.03 ml,23.19,4.58 and 4.33 ml/s,respectively.The changes of prostate volume,IPSS,QOL and Qmax at 3 months,12 months and 24 months after treatment were analyzed.ResultsAll patients tolerated well of PLFT performed in common therapy room except lightly bleeding,minor infection and temporary incontinence.There was no severe surgical adverse event.After 3 months,the prostate volume reduced to 43.85 ml,IPSS decreased to 11.63,QOL decreased to 2.44,Qmax rose up to 11.44 ml/s； The average values were 45.10 ml,12.23,2.61 and 10.91ml/s at 12 months after treatment.The corresponding values were 45.80 ml,12.37,2.66 and 10.82 ml/s,respectively at 24 months after treatment.Compared with pre-treatment,all the parameters showed significant improvement ( P ＜ 0.01 ).ConclusionsPLFT is one of the effective and safe treatment options for BPH patients with high risk factors.It can be safely used on day-surgery patients.The best effect appears at 3 months after treatment.

Objective To investigate the approach and safety of minimally invasive surgical procedures treating symptomatic caliceal diverticular calculi. Methods Clinical data of 21 cases with symptomatic caliceal diverticular calculi were retrospectively reviewed. Twelve females and 9 males aged 22 to 57 years old. The average diameter of caliceal diverticulum was 3.7 cm (2.5-7.0 cm) and average diameter of calculi was 2.3 cm (0.8-3.5 cm). The patients underwent flexible ureteroscopic lithotripsy, PCNL or mPCNL, laparoscopic techniques and laparoscopy-assisted transperitoneal PCNL, respectively. Four cases underwent flexible ureteroscopic lithotripsy. PCNL (2 cases) or mPCNL(5 cases)were performed in 7 cases. Nine cases underwent laparoscopic techniques. Laparoscopyassisted transperitoneal PCNL was performed in 1 case. Results The operations were performed successfully in 21 cases. No case need to transfer to open surgery during the operation and no major complications like perforation or organic injury were noted. One case with iatrogenic arteriovenous fistula of the kidney after 1 week postoperative was cured by delayed hemorrhage 2 days later, while clinical symptoms of 2 cases with residue calculi relieved. 19 cases without residue calculi were followed up for 6 to 12 month without recurrence. Conclusions After handling indication of treatment efficiently and creating advisable therapeutic decision-making, minimally invasive surgical procedures treating symptomatic caliceal diverticular calculi appears to be effective and safe.

Objective To evaluate the effect of transurethral feedback microwave thermotherapy with the ProstaLund CoreTherm Device(PLFT) in high risk patients with benign prostate hyperplasia (BPH). Methods Sixty-six high risk patients diagnosed with BPH, including aged ≥80 in 32 pa-tients, hypertension in 31 patients, diabetes in 5 patients, heart failure in 8 patients, chronic obstruc-tive pulmonary disease in 8 patients, cerebral infarction in 11 patients, fracture, amputation or joint stiffness unsuitable for lithotomy position in 3 patients, abnormal blood coagulation in 4 patients, pan-creatitis in 2 patients, cardiac arrhythmia in 6 patients and malignant tumor in 3 patients, were treated with PLFT using individual power at urethral local anesthesia, resulting in coagulation necrosis in 15%-30% of prostate tissue around urethra. Meanwhile, real-time monitoring the temperature of prostate and the tissue around it was used. All patients were evaluated by comparing volume of pros-tate, maximal urinary flow (Q_max), international prostate symptom score (IPSS) and quality of life questionnaire (QOL) in pre-treatment and three months after respectively. Results All of patients well tolerated PLFT. There was bleeding lightly, infection lightly and temporary incontinence. There was no severe surgical complication. After three months, the volume of prostate reduced from 62. 2 ml to 44.5 ml; IPSS decreased from 23. 4 to 11.7; QOL decreased from 4.5 to 2.4; Q_max rised from 4, 2 ml/s to 11.2 ml/s. All differences reached significance. Conclusion PLFT is one of effective and safe treatments for patients with BPH especial BPH complicating with severe conditions.