Objective To evaluate the comparability of test results of self-built human carcinoembryonic antigen(CEA)electro-chemiluminescence immunoassay(ECLIA)and imported reagent.Methods A total of different concentrations 77 fresh serum speci-mens were collected and detected CEA by two kinds of ECLIA kit.The results were analyzed with Excel2003 and SPSS1 9.0 soft-ware.Results The difference between each dose was significant (P <0.05),and the detection results between each had no signifi-cant difference (P >0.05);the sensitivity of the assay was 0.3 ng/mL,the intra coefficient of variation was 4.58%-5.83%,the inter coefficient of variation was 5.07%-5.97%,the analytical recovery was 99.13%-107.28%,the specificity of the assay had no cross reaction with CA1 99 and AFP.The correlation coefficient between two kinds of reagents determination results was greater than 0.95,with imported reagent as reference test,self-built carcinoembryonic antigen ECLIA clinical performance evaluation was acceptable.Conclusion The precision of the two kinds of ECLIA in detection of CEA accord to clinical requirement.Comparability exists in evaluating the acceptability of clinical.

Objective To determine the optimal positive end-expiratory pressure (PEEP) for volume-controlled ventilation using pulmonary electrical impedance tomography in the patients undergoing surgery with general anesthesia.Methods Fifty patients of both sexes,aged 18-64 yr,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,with body mass index of 18.5-28.0 kg/m2,scheduled for surgery for ureteral calculi under general anesthesia,were enrolled in this study.The patients were tracheally intubated after anesthesia induction and mechanically ventilated in volume-controlled mode,with tidal volume 6 ml/kg,mean arterial pressure was recorded at 3 min of ventilation and served as the baseline value,and then PEEP was increased with an increment of 3 cmH2O every 3 min until PEEP reached 15 cmH2 O.The percentage of dorsal pulmonary ventilation and peak airway pressure were recorded at 3 min of ventilation with different PEEPs.When the decrease in mean arterial pressure was more than 20％ of the baseline value during ventilation,deoxyepinephrine 0.1 mg was injected intravenously,and the consumption of deoxyepinephrine was recorded within 3 min of ventilation with different PEEPs.Results Peak airway pressure was gradually increased with the increase of PEEP (P＜0.05),the percentage of dorsal pulmonary ventilation was gradually increased when PEEP was 6 cmH2O (P＜ 0.05),and the consumption of deoxyepinephrine was gradually increased when PEEP was 15 cmH2O (P＜0.05).Conclusion The optimal PEEP is 12 cmH2O during volume-controlled ventilation with tidal volume of 6 ml/kg in the patients undergoing surgery with general anesthesia.

Objective To explore the mechanisms of mesenchymal stem cell-derived extracellu-lar vesicles(MSC-EVs)in improvement of renal injury in rats with diabetic nephropathy(DN)by reg-ulating mammalian target of rapamycin(mTOR)/p70 ribosome protein S6 kinase(S6K1)/coiled-coil myosin-like Bcl-2-interacting protein(Beclin 1)pathway.Methods The model of SD rats with DN was established by a method of high-fat diet combined with intraperitoneal injection of streptozotocin,and they were randomly divided into model group,MSC-EVs group,and MSC-EVs+MHY1485(mTOR activator)group,with 12 rats in each group.Another 12 SD rats were normally fed for 6 weeks and then intraperitoneally injected with an equal dose of sodium citrate solution as controls.After grouping with MSC-EVs and MHY1485,blood glucose and levels of renal function indicators[blood urea nitrogen(BUN),serum creatinine(Scr),and urinary microalbumin(UmALB)]in rats were detected.HE staining was used to detect the pathological morphology of renal tissue in rats of each group;immunohistochemistry was used to detect the expression of mTOR/S6K1/Beclin 1 pathway related proteins in the renal tissues of rats in each group;the Western blot was used to de-tect the mTOR/S6K1/Beclin 1 pathway and autophagy-related protein expression in the renal tissues of rats in each group.Results Compared with the control group,the renal tissue morphology of rats in the model group were impaired,and the blood glucose,BUN,Scr,UmALB,relative positive ex-pressions of p-mTOR and p-S6K1,p-mTOR/mTOR,p-S6K1/S6K1 increased significantly(P＜0.05),while microtubule associated protein 1A/1B light chain 3(LC3)Ⅱ/LC3 Ⅰ,expression of Beclin 1 protein,and relative positive expression of Beclin 1 significantly reduced(P＜0.05);compared with the model group,the MSC-EVs group had less impairment in the renal tissue mor-phology,and the blood glucose,BUN,Scr,UmALB,relative positive expressions of p-mTOR and p-S6K1,p-mTOR/mTOR,and p-S6K1/S6K1 decreased significantly(P＜0.05),while expression of LC3 Ⅱ/LC3 Ⅰ,Beclin 1 protein,and relative positive expression of Beclin 1 increased signifi-cantly(P＜0.05);compared with the MSC-EVs group,the impairment of the renal tissue morphol-ogy was worse in the MSC-EVs+MHY1485 group,and the blood glucose,BUN,Scr,UmALB,rel-ative positive expressions of p-mTOR and p-S6K1,expression of p-mTOR/mTOR,and p-S6K1/S6K1 increased significantly(P＜0.05),while the expression of LC3Ⅱ/LC3Ⅰ,Beclin 1 protein,and rela-tive positive expression of Beclin 1 decreased significantly(P＜0.05).Conclusion MSC-EVs can enhance autophagy,reduce levels of blood glucose,Scr,BUN and urinary protein in rats with DN,alleviate renal tissue damage,and the mechanism may be achieved by inhibiting the activation of the mTOR/S6K1/Beclin 1 pathway.

Objective To explore the mechanisms of mesenchymal stem cell-derived extracellu-lar vesicles(MSC-EVs)in improvement of renal injury in rats with diabetic nephropathy(DN)by reg-ulating mammalian target of rapamycin(mTOR)/p70 ribosome protein S6 kinase(S6K1)/coiled-coil myosin-like Bcl-2-interacting protein(Beclin 1)pathway.Methods The model of SD rats with DN was established by a method of high-fat diet combined with intraperitoneal injection of streptozotocin,and they were randomly divided into model group,MSC-EVs group,and MSC-EVs+MHY1485(mTOR activator)group,with 12 rats in each group.Another 12 SD rats were normally fed for 6 weeks and then intraperitoneally injected with an equal dose of sodium citrate solution as controls.After grouping with MSC-EVs and MHY1485,blood glucose and levels of renal function indicators[blood urea nitrogen(BUN),serum creatinine(Scr),and urinary microalbumin(UmALB)]in rats were detected.HE staining was used to detect the pathological morphology of renal tissue in rats of each group;immunohistochemistry was used to detect the expression of mTOR/S6K1/Beclin 1 pathway related proteins in the renal tissues of rats in each group;the Western blot was used to de-tect the mTOR/S6K1/Beclin 1 pathway and autophagy-related protein expression in the renal tissues of rats in each group.Results Compared with the control group,the renal tissue morphology of rats in the model group were impaired,and the blood glucose,BUN,Scr,UmALB,relative positive ex-pressions of p-mTOR and p-S6K1,p-mTOR/mTOR,p-S6K1/S6K1 increased significantly(P＜0.05),while microtubule associated protein 1A/1B light chain 3(LC3)Ⅱ/LC3 Ⅰ,expression of Beclin 1 protein,and relative positive expression of Beclin 1 significantly reduced(P＜0.05);compared with the model group,the MSC-EVs group had less impairment in the renal tissue mor-phology,and the blood glucose,BUN,Scr,UmALB,relative positive expressions of p-mTOR and p-S6K1,p-mTOR/mTOR,and p-S6K1/S6K1 decreased significantly(P＜0.05),while expression of LC3 Ⅱ/LC3 Ⅰ,Beclin 1 protein,and relative positive expression of Beclin 1 increased signifi-cantly(P＜0.05);compared with the MSC-EVs group,the impairment of the renal tissue morphol-ogy was worse in the MSC-EVs+MHY1485 group,and the blood glucose,BUN,Scr,UmALB,rel-ative positive expressions of p-mTOR and p-S6K1,expression of p-mTOR/mTOR,and p-S6K1/S6K1 increased significantly(P＜0.05),while the expression of LC3Ⅱ/LC3Ⅰ,Beclin 1 protein,and rela-tive positive expression of Beclin 1 decreased significantly(P＜0.05).Conclusion MSC-EVs can enhance autophagy,reduce levels of blood glucose,Scr,BUN and urinary protein in rats with DN,alleviate renal tissue damage,and the mechanism may be achieved by inhibiting the activation of the mTOR/S6K1/Beclin 1 pathway.