Objective To explore the feasibility of carrying out the common imprecision range among different biochemical systems in different laboratories.Methods Biochemical professionals visited 18 third-grade class A hospitals in Hebei Province,investigated the internal quality control data of 21 biochemical tests and made classification according to certain parameter criterias.Data were collected from April to September,2010 and calculated for cumulative mean,standard deviation (s) and CV.Data were compared according to 1/3,1/4 of TEa established by CLIA'88 and allowable CVb％ derived from biological variants.Results Among 18 hospitals,5 (27.8％) set their target value by mean value of 6 months,5(27.8％) by continuous 20 days and 8(44.4％) by the given value of the supplier.CVs of 21biochemical tests were quite different among 18 biochemistry laboratories,in which LDH was 6.79 times and CK was 76.79 times different from one another.35.5％-94.1％ biochemical tests met the requirement of CV ＜ 1/3TEa and 0.0％-91.7％ met the requirement of CV ＜ 1/4TEa.0.0％-94.1％ of tests were below allowable CVb％ 16/21 (76.2％) tests could satisfy the requirement of CV ＜ 1/3TEa.The top five tests which didn't meet the requirements were Na,Urea,TBIL,ALT and Glu.Conclusions The internal quality control among biochemistry laboratories in Hebei Province has not been standardized yet.According to the survey data,biochemistry laboratories of third-grade class A hospitals may set 75％ point of imprecision as a reference.After a period of improvement,we will set common imprecision range among biochemistry laborotories in Hebei Province and even in China.

Objective To investigate the role of Rho kinase (ROCK) in the protective effects of hydrogen on intestinal epithelial barrier function in sepsis. Methods Caco-2 cells were cultured routinely, and divided into 6 groups randomly (n=3):control group (C group), hydrogen-rich medium group (H group), lipopolysaccharide (LPS)-treatment group (L group), hy?drogen+LPS-treatment group (HL group), Rho kinase inhibitor (Y-37632) treatment group (Y group) and Rho kinase inhibi?tor Y-27632+LPS-treatment group (YL group). H group was treated with 0.6 mmol/L hydrogen-rich media. The concentra?tion of LPS and Y-27632 were 50 mg/L and 25μmol/L separately. After the Caco-2 monolayer model was established, the transepithelial electrical resistance (TEER) values were measured regularly. When the TEER value reached 800Ω·cm2, the treatment was administered. Then TEER values were measured at 6 h, 12 h and 24 h, and FITC-dextran permeability was de?tected at 24 h. Cells were seeded on 6-well plates. After cell density reached 80%-90%, treatments were given randomly. The real time-polymerase chain reaction (RT-PCR) was conducted to assess mRNA levels of ZO-1 and ROCK mRNA. ZO-1 and ROCK protein expression levels were detected by Western blot assay. Results Compared with C group, TEER values were elevated in 12 h and 24 h in H group (P<0.05). There were no statistical significances in FITC-dextran permeability,
protein expression levels of ZO-1 and ROCK between C group and H group (P>0.05). TEER values were elevated at 6 h, 12 h and 24 h in Y group (P<0.05). There was no significant difference in FITC-dextran permeability between C group and Y group (P > 0.05). The mRNA expression of ZO-1 increased and mRNA expression of ROCK decreased in Y group (P <0.05). The TEER values reduced at 6 h, 12 h and 24 h in L group. The FITC-dextran permeability increased significantly, mRNA and protein expressions of ZO-1 significantly decreased, mRNA and protein expressions of ROCK significantly in?creased in L group (all P<0.05). Compared with L group, TEER values increased significantly at 6 h, 12 h and 24 h in YL group, FITC-dextran permeability decreased, mRNA expressions of ZO-1 increased, mRNA expressions of ROCK de?creased in YL group (P<0.05). Compared with L group, TEER values increased at 6 h, 12 h and 24 h in HL group, FITC-dextran permeability reduced markedly, protein expressions of ZO-1 increased at each time point, protein expressions of ROCK decreased at each time point in HL group (P<0.05). Conclusion Hydrogen can protect intestinal barrier function against sepsis, ameliorate the integrity and permeability of intestinal epithelium and increase the expressions of intercellular tight junction proteins. The suppression of Rho kinase over-expression induced by LPS may be involved in these protective effects of hydrogen.

AIM To study the effects of matrine (Ma) on the action potential and contractile force in guinea pig papillary muscles. METHODS Conventional microelectrode technique was used to record the fast action potentials (FAP) and slow action potentials (SAP) induced by histamine and BaCl_2 of guinea pig papillary muscles. RESULTS Ma 10,25,50 ?mol?L -1 dose-dependently prolonged the action potential duration at 50%, 90% repolarization (APD_ 50 , APD_ 90 ) and effective refractory period (ERP) of FAP, and lengthened the APD_ 50 , APD_ 90 of SAP induced by histamine and BaCl_2 when perfused with KCl 25 mmol?L -1 Tyrode's solution. The maximal upstroke velocity (V_ max ) of FAP, SAP and contractile force (Fc) were not affected by matrine 10,25,50 ?mol?L -1 . CONCLUSION It was suggested that Matrine could block K + channels in the myocardium.-

OBJECTIVE:To determine the content of levofloxacin by PVC membrane selective electrode. METHODS: A glass electrode coated with levofloxacin PVC membrane was prepared for the first time with the molecular complex of levofloxacin iodide and bismuth iodide as electric active material, and a series study was performed on its responsibility. RESULTS: The electrode gave Nernst response to levofloxacin over the concentration range of 5.0?10-3～1.0?10-5 moL?L-1 with a slope rate of 56.5mV?pC-1, a suitable pH of 2.5～4.0, and an average recovery rate of 98.31%～101.6%(2.80%～4.90%). CONCLUSION: The electrode was simple in operation, and it has a rapid response and good reproducibility, and it is applicable for the quantitative determination of levofloxacin.

Objective To investigate the effect of hydrogen on endotoxin-induced expression of zonula occludens-1 (ZO-1) in human colon epithelial cells (Caco-2 cells).Methods Caco-2 cells were cultured routinely,seeded in Transwell chambers or wells,and randomly divided into 4 groups (n =45 each) using a random number table:control group (group C);hydrogen-rich culture medium group (group H);endotoxin group (group E);hydrogen-rich culture medium + endotoxin group (group HE).The cells were cultured in high-glucose DMEM culture medium in group C.The cells were incubated in hydrogen-rich culture medium containing hydrogen 0.6 mmol/L in group H.The cells were incubated in highglucose DMEM culture medium containing 50 μg/ml lipopolysaccharide in group E.The cells were incubated in hydrogen-rich culture medium containing 50 μg/ml lipopolysaccharide and 0.6 mmol/L hydrogen in group HE.Transepithelial electrical resistance (TEER) was measured before incubation or culture,and at 6,12 and 24 h of incubation or culture.The viability of Caco-2 cells was measured by methyl thiazolyl tetrazolium assay at 24 h of incubation or culture.The expression of ZO-1 mRNA in Caco-2 cells was determined using real-time reverse transcriptase polymerase chain reaction at 6,12 and 24 h of incubation or culture.The distribution of ZO-1 in Caco-2 cells was observed by immunofluorescence at 24 of incubation or culture.Results Compared with group C,TEER was significantly decreased at 6,12 and 24 h of incubation or culture,and the expression of ZO-1 mRNA was significantly down-regulated in E and HE groups (P＜0.05),and no significant change was found in the parameters mentioned above in group H (P＞0.05).Compared with group E,TEER was significantly increased at 6,12 and 24 h of incubation or culture,and the expression of ZO-1 mRNA was significantly up-regulated in group HE (P＜0.05).The distribution of ZO-1 protein in cell membrane became discontinuous,and the distribution of ZO-1 protein in cytoplasm was significantly increased in group E.Compared with group E,the distribution of ZO-1 protein in cell membrane was significantly increased and gradually became continuous,and the distribution of ZO-1 protein in cytoplasm was significantly decreased in group HE.Conclusion The mechanism by which hydrogen reduces the damage to human colon epithelial cell barrier is related to up-regulation of ZO-1 expression and improvement in the redistribution of ZO-1 protein.

Objective To investigate the biological effects of Pseudomonas aeruginosa quorum sensing molecule OdDHL on murine mast cells. Methods The molecule structure and purity of synthesized OdDHL were confirmed by mass spectrum or proton nuclear magnetic resonance (NMR) and high-performance liquid chromatography, respectively. Its biological activity was checked using a quorum sensing sensor bacterial strain. The viability, apoptosis and intracellular calcium changes of P815 cell line in response to different concentration of OdDHL were determined. Results The biological active OdDHL was synthesized successfully. OdDHL inhibited proliferation of P815 cells in a dose, and time dependent manner. It also induced apoptasis and intracellular calcium release in P815 cells. Conclusion Psendomonas aeruginosa quorum sensing molecule OdDHL induces apoptosis and intracellular calcium release in murine mast cell line P815.

Objective To estabhsh a rat portacaval shunt model of portal vein arterialization (PVA)by using right renal artery,andtoinvestigateitsinfluence on portal velnpressure,liver funciton and hepatic pathology.Method Forty-three Sprague-Dawley rats were assigned to PVA group(33 rats)and control group(10 rats).Portal pressure,liver function and pathological changes were evaluated at day 2,2 weeks and 2 months after surgery,respectively.Results The experimental model was successfully established in 30 out of 33(91%)rats.At day 2,2 weeks and 2 months after the operation,the portal pressure increased significanfly(P<0.05)compared with the control group,but no significant differences were found in the senrum level of alanine amlnotransferase,total bilirubin,total bile acid and creatinine.There were no patholgiccal changes from day 2 to 2 weeks after surgery,only postoperative expanslon of the sinusoidal snace was found on 2 months after surgery.Conclusion The rat model of PVA by renal artery was successfully established with the hand-suture mierosurgical techniques.The portal vein pressure maintained at a high level after PVA,meanwhile,no negative effect was found on the liver function and hepatic histological structure changes.

Objective To explore the method of pre expanded deltopectoral flap for repairing post burn faciocervical scars.Methods Anterior axillary incisions were made and appropriate expanders were implanted above anterior chest wall at the first stage.After a 4 6 months' expanding,the flaps based on perforating branches of the internal mammary artery,branches from the thoracoacromi al area,or perforating branches from deltoid muscle,were designed and raised according to scars and dominant vessels.The donor sites were closed at same time without skin graft.Results 43 patients with 51 flaps were operated for reconstruction of post burn faciocervical scars.All flaps and donor sites survived well.Conclusions Pre expanded deltopectoral flap is an ideal donor site for repairing post-burn faciocervical scars.

Objective To investigate the clinical results of minimally invasive fixation of the sacroiliac triangle for vertically unstable pelvic posterior ring injury. Methods A retrospective study was conducted of 20 patients who had been treated for vertically unstable pelvic posterior ring from January 2014 to August 2016. They were 12 males and 8 females, aged from 20 to 58 years ( average, 35 years ) . According to Tile classification for pelvic fractures, there were 4 cases of type C1. 1, 6 cases of type C1. 2, 7 cases of type C1. 3 and 3 cases of type C2. Their posterior rings were treated by fixation through posterior paraspinal approach with S1-iliac pedicle screws plus percutaneous sacroiliac screws, and their anterior rings by closed reduction and internal fixation with cannulated screws, Infix or plate following open reduction. The incision length, operation time and intraoperative blood loss were recorded. Postoperative reduction quality was assessed by Matta radio-logical criteria and pelvic function by Majeed criteria at the final follow-ups. Results Altogether 20 fixation systems of S1-iliac pedicle screws and 37 sacroiliac joint screws were inserted in this series. The length of incision ranged from 5. 5 to 7. 6 cm ( average, 6. 2 cm ) , the operation time from 89 to 130 minutes ( average, 98 minutes) and the intraoperative blood loss from 110 to 320 mL (average, 195 mL). According to Matta ra-diological criteria, reduction was excellent in 13, good in 5 and fair in 2 cases, with an excellent and good rate of 90％. The follow-up time for the 20 patients ranged from 6 to 15 months ( average, 9 months ) . The healing time ranged from 10 to 14 weeks ( average, 12. 5 weeks ) . At the final follow-ups, X-ray and CT three-dimensional reconstruction showed fine fracture union. By the Majeed criteria, the pelvic function was excellent in 11 cases, good in 5, fair in 3, and poor in one, with an excellent and good rate of 80％. No loosening, breakage or pull-out of pedicle screws or sacroiliac screws happened. Conclusion Minimally invasive fixation of the sacroiliac triangle for vertically unstable pelvic posterior ring injury can lead to precise placement, quick recovery, small incision and good functional outcome.

Objective:To evaluate the best parameter of predicting the operation time and clearance of flexible ureteroscopic lithotripsy through comparing correlations between three stone burden parameters (diameter, area, volume) and the operation time or clearance retrospectively.Methods:Clinical data and CT images of 70 patients who performed flexible ureteroscopic lithotripsy because of single kidney stone in our center from January 2018 to December 2019 were retrospectively reviewed. There were 46 males and 24 females; their age was (47±12) years old. Stones were located on the left side in 28 cases and right side in 42 cases; 32 cases in the renal pelvis , 29 cases in the lower calyx, 6 cases in the middle calyx and 3 cases in the upper calyx. The free software ITK-SNAP 3.6.0 to segment kidney stones in 3D models with the CT image was used. The stone volume was calculated automatically after the segment. The largest section of the stone on the CT coronal plane was selected to measure the maximum length (D) and width (d) of the stone, the maximum diameter of the stone was D, and the stone area was calculated using the formula 0.25πDd. The patients were divided by the operation clearance into total clearance group and partial clearance group. The correlations between three stone burden parameters (volume, diameter, area) and operation time or clearance of the flexible ureteroscopic lithotripsy were compared. Simple linear regression model was also applied to compare three measurement methods. Then other factors which may affect the operation time was evaluated with the stepwise linear regression model, such as stone component and location.Results:The median operation time was 63(50, 84)min. Of 70 cases, 47 cases were in the stone-free group, with stone volume 633(248, 1 087)mm 3, maximum diameter 15(10, 19)mm, and area 82(49, 186)mm 2. 23 cases were in the non stone-free group, with volume 696(408, 1 418)mm 3, maximum diameter 15(12, 20)mm, area 105(73, 201)mm 2. There was no difference between the two groups in volume, maximum diameter and area of stones (all P>0.05). The stone-free rate of the diameter >2 cm group was 55% (6/11), ≤2 cm group was 70% (41/59). There was no significant difference between the two groups. Correlation between stone volume and operation time is the best. The correlation coefficient of stone volume is 0.58, of stone diameter is 0.33, of stone area is 0.34. Coefficients of determination of the stone volume linear regression is the best, too. R square of stone volume is 0.36, of stone diameter is 0.17, of stone area is 0.22. Forward stepwise regression model shows stone volume is the most important parameter which correlate with operation time. None of stone volume, diameter or area has significant correlation with the clearance of stone. Conclusion:Stone volume is the best predictive parameter of the stone burden because it has the best correlation with the operation time of the flexible ureteroscopic lithotripsy of the single kidney stone.