BACKGROUND:The stability of the pelvis is mainly determined by the posterior pelvic ring and the sacroiliac joint.The posterior pelvic ring injury and the dislocation of the sacroiliac joint caused by high energy impacts such as car accidents increase year by year.Surgical treatment is the best method,and there are many kinds of endophytorepair methods in clinical practice,but which treatment method has the best biomechanical properties is still controversial. OBJECTIVE:To compare the biomechanical properties of three kinds of internal implants:anterior double plates,posterior bridging plate and tension nail in the repair of unilateral unstable pelvic posterior ring injury,to provide a reference for the clinical treatment and development of a new pelvic tension screw. METHODS:(1)Finite element simulation:Mimics,Wrap and SolidWorks were used to establish normal pelvic model,unilateral injured pelvis model,and three kinds of internal implant repaired models(anterior double plates,posterior bridging plate and tension nail).Ansys was used to analyze the stress and deformation of the models.(2)Biomechanical test:A total of 15 intact pelvic specimens were randomly grouped into five groups,normal pelvic model,unilateral injured pelvis model,anterior double plates,posterior bridging plate and tension nail groups.The mechanical test was performed using an Instron E10000 testing machine. RESULTS AND CONCLUSION:(1)Simulation:In the normal pelvic model,the average displacement of the sacrum was 0.174 mm,and the maximum stress of the sacral iliac bone was 10.51 MPa,and the stress distribution was uniform.The mean sacral displacement of the unilateral injured pelvis model was 0.267 mm,and the stress concentration of the model was obvious.The mean displacement of the sacrum in the three repaired models was close to that in the normal pelvic model,and the stress distribution of the sacral iliac bone in the tension nail repaired model was uniform.(2)Mechanical test:The stiffness of the normal pelvic model was(226.38±4.18)N/mm,and that of the unilateral unstable pelvic model was the smallest(130.02±2.19)N/mm.The deviation of the normal pelvic model stiffness and the three repaired models'stiffness were all within(±10%),and the repair effect was obvious.(3)The simulation results were in agreement with the experimental results.(4)The biomechanics of the tension nail repaired model was the most similar to that of the normal pelvis,and this method was the best.The repairing stiffness of the anterior double plate was too large,and the stress shielding effect was more significant.The posterior bridging plate repair could not solve the compensatory effect of the normal side soft tissue and had defects.This study provides an optimal basis for clinical surgery.(5)The new type of pelvic tension nail should be improved from the point of view of the tension nail to retain the good biomechanical properties of the tension nail,while adding other advantages,such as being used for the osteoporotic pelvis.

BACKGROUND:Pauwels Ⅲ femoral neck fracture is a typical unstable fracture characterized by high vertical shear force and high incidence of postoperative complications.At present,there are many fixation methods for Pauwels Ⅲ fracture,and there is no clear conclusion as to which internal fixation is the best fixation method for Pauwels Ⅲ femoral neck fracture in young adults. OBJECTIVE:To compare the clinical effect of three inverted triangle cannulated screws assisted transverse lag screws and femoral neck system in fixing Pauwels Ⅲ femoral neck fractures of young adults. METHODS:From May 2021 to December 2022,21 young and middle-aged patients with Pauwels Ⅲ femoral neck fracture were treated with three inverted triangle cannulated screws assisted by transverse lag screws and femoral neck system in Affiliated Hospital of Southwest Medical University.Of them,9 patients were treated with three inverted triangle cannulated screws and one transverse lag screws perpendicular to the fracture line as the 3+1 cannulated screw group and 12 patients were treated with femoral neck system as the femoral neck system group.The two fixation methods were compared in terms of operation time,intraoperative blood loss,total incision length,intraoperative fluoroscopy times,fracture healing time,and limb function. RESULTS AND CONCLUSION:(1)All patients were followed up.Patients in the 3+1 cannulated screw group were followed up for 10-25 months,with a mean of(17.44±4.30)months.The patients in the femoral neck system group were followed up for 8-24 months,with a mean of(15.58±4.68)months.(2)The intraoperative fluoroscopy times and Harris score at 3 months postoperatively in the femoral neck system group were better than those in the 3+1 cannulated screw group,and the difference was statistically significant(P<0.05).The intraoperative blood loss,total incision length,and femoral neck shortening distance in the 3+1 cannulated screw group were better than those in the femoral neck system group,and the differences were statistically significant(P<0.05).There was no significant difference in operation time,fracture healing time,and Harris score at the last follow-up between the two groups(P>0.05).(3)It is indicated that three inverted triangle cannulated screws assisted transverse lag screw and femoral neck system can achieve good clinical effects in the treatment of young and middle-aged Pauwels Ⅲ femoral neck fracture.The femoral neck system has fewer intraoperative fluoroscopy times and better early overall stability,while the 3+1 cannulated screw is more minimally invasive,easier to operate.Both fixation methods are worthy of clinical application and promotion,and can be selected according to the actual clinical situation.

Objective To investigate the biomechanical properties of a novel sacroiliac lag screw with a spiral blade.Methods Percutaneous sacroiliac lag screws were used as the controls.Polyurethane material was used to simulate the trabecular bone,and the pullout resistance performance was tested on an Instron mechanical testing machine.Subsequently,pelvic specimens were utilized to analyze the static stiffness and dynamic stability of the novel sacroiliac lag screw in repairing sacroiliac joint injuries under normal standing conditions,with normal pelvis,single-sided sacroiliac joint injury pelvis,percutaneous sacroiliac lag screw-single screw repair,and percutaneous sacroiliac lag screw-double screw repair as controls.Results The damage to the polyurethane material after screw extraction was smaller in the novel sacroiliac lag screw group.The average effective holding displacement of the novel sacroiliac lag screw was significantly greater than that of the percutaneous sacroiliac lag screw(P＜0.05).However,the maximum resistance to the pullout force for the percutaneous sacroiliac lag screw was significantly higher than that for the novel sacroiliac lag screw(P＜0.05).The stiffness after repair of sacroiliac joint injuries was significantly higher when using a single sacroiliac lag screw than when using two percutaneous sacroiliac lag screws(P＜0.05).The displacement amplitude was the highest in the sacroiliac joint injury group,followed by that in the normal group.The displacement amplitudes in the other groups were similar;however,the differences were statistically significant(P＜0.05).The dynamic stability of the sacroiliac lag screw repair group was the best,slightly better than that of the percutaneous sacroiliac lag screw-double screw repair group,and the dynamic stability of the sacroiliac joint injury group was the worst.The novel sacroiliac lag screw effectively repaired the sacroiliac joint injuries.Conclusions The novel sacroiliac lag screw can effectively hold the trabecular bone and has practical clinical utility.

Cadaverine is a biogenic amine that has the potential to become an important platform chemical for the production of industrial polymers, such as polyamides and polyurethanes. We reported here a lysine decarboxylase from Klebsiella oxytoca. The lysine decarboxylase from Klebsiella oxytoca was cloned to Escherichia coli to get the strain LN18. The specific activity of the crude protein from LN18 reached 30 000 U. The molecular weight was about 80 kDa. The optimum temperature and pH of the crude protein were 55 ℃ and 5.5 respectively. The specific activity could keep over 30% at pH 8.0 compared the one at pH 5.5, much difference from Escherichia coli lysine decarboxylase CadA. Mg²⁺ was positive to the specific activity, whereas Fe²⁺, Zn²⁺ and Ca²⁺ were negative.
Bacterial Proteins ; genetics ; metabolism ; Cadaverine ; Carboxy-Lyases ; genetics ; metabolism ; Escherichia coli ; metabolism ; Hydrogen-Ion Concentration ; Klebsiella oxytoca ; enzymology ; genetics ; Temperature

Objective:To study the effect of different dose of persicae semen extract extract(PSE) to barrier function of the intestinal mucous membrane and immunologic function in acute pancreatitis rats.Methods:A total of 48 rats were divided into model control group,low dose,medial dose and high dose PSE groups,and there were 12 rats in each group.Another 12 rats were Sham-operation group.After anesthesia recovery,rats in low dose,medial dose and high dose PSE groups respectively received PSE 0.12 g/kg,0.248 g/kg and 0.36 g/kg,and rats in Sham-operation group and model control group receive isovolumetric distilled water,once per 6 h,4 times in 24 hours.All rats were anesthetized by 10%chloral hydrate after in 24th hour after dosing.Thorax and enterocoelia were opened; 5 ml of blood were respectively drawed to EDTA-anticoagulation tube and un-anticoagulation tube from aorta abdominalis.CD4+, CD8+and Treg cells were determined by direct fluorescent-labelded flow cytometry.IgA, IgG and IgM were determined by immunoturbidimetry.Serum amylase was determined by EPS-G7 substrate,D-lactic acid was determined by enzymology, and serum diamine oxidase was determined by active ration of colorimetry method.Pathological examination of small intestine mucous membrane tissue was taken after HE staining.sIgA in small intestine was determined by radioimmunoassay.mRNA of TLR4 and NF-κBp65 in small intestine tissue was determined by RT-PCR.Results:(1) Serum amylase,D-lactic acid and diamine oxidase in medial dose and high dose PSE groups were significantly decreased ( P<0.01 ) , and sIgA in small intestine was significantly increased ( P<0.01).These indicators were significantly different in medial dose and high dose PSE groups(P<0.01).(2) CD4+and CD4+/CD8+in medial dose and high dose PSE groups were significantly increased(P<0.01),and CD8+,Treg cells were significantly decreased(P<0.01) compared with those in low dose PSE group.These indicators were significantly different in medial dose and high dose PSE groups(P<0.01).(3) IgA,IgG and IgM in medial dose and high dose PSE groups were significantly decreased(P<0.01) compared with those in low dose PSE group.These indicators were significantly different in medial dose and high dose PSE groups(P<0.01).(4) Small intestine mucous membrane tissue in Sham-operation group was not damaged significantly,but that in model control group was damaged significantly.Small intestine mucous membrane tissue in low dose PSE group was similar to that in model control group,and damage in medial dose and high dose PSE groups was decreased significantly.( 5 ) mRNA of TLR4 and NF-κBp65 in small intestine tissue in medial dose and high dose PSE groups were significantly increased ( P<0.01 ) compared with those in low dose PSE group.These indicators were significantly different in medial dose and high dose PSE groups ( P<0.01 ).Conclusion: PSE has protective effect to barrier function of the intestinal mucous membrane,and significantly improve the immunologic function.

Objective To study the association of the serum alanine aminotransferase (ALT) level with cardiovascular risks in patients with type 2 diabetes mellitus (T2DM).Methods A total of 676 patients with T2DM who excluded liver disease due to chronic viral hepatitis,autoimmune,drugs,alcohol,and other hereditary were selected.According to the ALT level,676 patients were assigned into elevated ALT group (ALT ＞40 U/L,126 cases) and normal ALT group (ALT 5-40 U/L,550 cases).And normal ALT group were divided into 4 groups on the interquartile distance:group 1 (ALT 5-11 U/L,108 cases),group 2 (ALT 12-15 U/L,114 cases),group 3 (ALT 16-21 U/L,127 cases),group 4 (ALT 22-40 U/L,201cases).The age,duration of diabetes,body mass index (BMI),waist-to-hip ratio (WHR),blood pressure,triglyceride (TG),total cholesterol (TC),high density lipoprotein cholesferol (HDL-C),low density lipoprotein cholesferol (LDL-C),fasting plasma glucose (FPG),2 h postprandial blood glucose (2 hPG),glycosylated hemoglobin (HbA1c),uric acid (UA),fasting insulin and homeostasis model assessment insulin resistance index (HOMA-IR) was compared among these groups.Results The levels of BMI,WHR,diastolic blood pressure,FPG,2 hPG,HbA1c,fasting insulin,TG,HOMA-IR and UA in elevated ALT group were higher than those in normal ALT group [(26.80 ± 3.60) kg/m2 vs.(23.40 ± 3.50) kg/m2,0.95 ±0.05 vs.0.91 ± 0.05,(75.3 ± 9.3) mm Hg (1 mm Hg =0.133 kPa) vs.(69.2 ± 9.5)mm Hg,(9.24 ± 2.56)mmol/L vs.(8.53 ± 2.78) mmol/L,(15.25 ± 4.62) mmol/L vs.(14.37 ± 5.06) mmoUL,(8.31 ± 1.76)％ vs.(7.78 ± 1.94)％,(10.76 ± 6.78) mU/L vs.(7.85 ± 7.04) mU/L,(2.73 ± 2.40) mmol/L vs.(2.20 ± 2.78)mmol/L,4.13 ± 2.76 vs.3.06 ± 2.63,(332.42 ± 95.12) μ mol/L vs.(285.14 ± 79.53) μ mol/L] (P ＜ 0.05),and HDL-C was lower than that in normal ALT group [(1.06 ± 0.27) mmol/L vs.(1.15 ± 0.57) mmol/L] (P ＜0.05).Compared with that in normal ALT group,the age was younger,and the duration of diabetes was shorter in elevated ALT group [(49.6 ± 10.5) years vs.(57.5 ± 11.3) years,(37.9 ±42.0) months vs.(54.5 ± 57.8) months] (P ＜ 0.05).The levels of FPG,2 hPG,HbA1c and UA in group 4 were higher than those in group 1,2,3 [(9.18 ± 3.01) mmol/L vs.(8.33 ± 2.57),(8.38 ± 2.52),(8.45 ± 2.73) mmol/L;(14.56 ± 4.80) mmol/L vs.(13.15 ± 5.72),(13.42 ± 4.56),(13.50 ± 5.17) mmol/L; (7.81 ± 1.98)％ vs.(6.76 ± 1.84)％,(6.79 ± 2.10)％,(6.88 ± 2.43)％; (288.24 ± 78.26) μ mol/L vs.(271.15 ± 75.43),(273.27 ± 71.25),(275.56 ± 69.57) μ mol/L] (P ＜ 0.05) ; HOMA-IR was lower than that in group 1,2,3(2.67 ± 2.65 vs.2.84 ± 2.53,2.98 ± 3.10,3.12 ± 2.57,P ＜ 0.05).Conclusion TheincreaseofALTlevel is associated with the clustered cardiovascular risk factors and insulin resistance in patients with T2DM.

Objectives It was constructed that the replication defective adenoviral vectors carried the short hairpin sequences of mouse SCP2.And we will make a further study of mechanism between SCP2 gene and cholesterol stone in gallbladder.Methods The short hairpin sequences of mouse SCP2 were cloned by two-step PCR,and connected together with the plasmid pDC312.The Admax Adenoviral Vector System was used to generate the replication defective adenoviral vectors,which were purified by CsCl method.The processes of TCID50 were applied to detect the titers of the adenoviral vectors.Furthermore,Protein levels of SCP2 were determined by Western blot analysis,and the levels of SCP2、CYP7A1、HMGCR mRNA from the hepa1-6 cell of mouse were measured by the usage of RT-PCR.Results SCP2mRNA and SCP2 protein were down-regulated by the replication defective adenoviral vectors carried the SCP2-shRNA.With the decreasing SCP2mRNA,the levels of HMGCRmRNA were down-regulated at same the time,while CYP7A1mRNA were up-regulated.Conclusions The replication defective adenoviral vectors carried SCP2-shRNA were constructed successfully.The lower levels of SCP2 could affect the activities of HMG-CoA reductase and CYP7-a enzyme,which caused the variations of cholesterol metabolism and then decreased the formation of cholesterol stone.

Objective To analyze risk factors in order to predict the in-hospital mortality of patients with se-vere acute pancreatitis (SAP), especially the factor of total cholesterol. Method Factors for predicting in-hospi-tal mortality were evaluated retrospectively from the clinical data collected from 338 SAP patients of Tianjin Nankai Hospital between January 1999 and December 2008 according to the Guidelines for for clinical diagnosis and classi-fication of Acute Panereatitis set by the Society of Chinese Medical Association in 2003. The patients were treated with intensive care, blood routine examination, blood biochemical test and even computed tomography within 24 hours after admission. The patients were divided as per outcome into deceased and survivor group. All patients were admitted within 72 hours after the onset of symptoms. The Off-square test was used for univariate analysis and multivariate test was performed by logistic regression. Results Compared with TC≤3.67 mmol/L, when the TC was between 3.67 -4.37 mmol/L, OR was 0.664 (P = 0.412), while TC was between 4.37 mmol/L and 5.23 mmol/L, OR was 0.144 (P =0.021).The OR was 1.013 (P =0.018) when TC was ≥5.23 mmol/L. The variation of serum TC levels was accompanied with the changes of C-reactive protein (CRP). When the CRP was ≥170 mg/L, OR was 7.074 (P =0.031). When the serum ALB≤30 g/L, OR was 7.224 (P =0.029).Conclusions The CRP, ALB, TC can be used for early predicting the in-hospital mortality of SAP patients. TC is a protective factor when it was between 4.37 mmol/L and 5.23 mmol/L, while it is a risk factor when ≥5.23 mmol/L or≤3.67 mmol/L. CRP> 170 mg/L or ALB < 30 g/L increases the probability of fatal outcome. Low level of albumin is a stronger predictor than the high level of CRP. Moderate elevation of TC level seems to in-crease the resistance to inflammation and hence improving the survival rate of patients with SAP and reducing the in-hospital mortality.

Objective To analyze the etiology,diagnosis and therapy of benign biliary strictures and im-prove curative and preventive effects. Methods 212 patients suffering from benign biliary strictures in Nankai Hos-pital from January 2004 to December 2006 were retrospectively analyzed. Results Inflammatory strictures (65.12%,140/215) and strictures caused by operations (20.46%,44/215) were the most two causes. Strictures parts were mainly located in the latter segment of common bile duct 52.09% (112/215). In our group,the stent of strictures parts took 31.37% (64/204), bilioendodraignage 18.13% (37/204), and the modification of strictures parts 43.63% (89/204) as well as resection of stricture parts 1.96% (4/204). Conclusions Inflammatory stricture is the main cause in benign biliary strictures and the main locus is the hinder segment of common bile duct. The di-agnesis of benign biliary strictures before operation is important because it can help to decide the approach way and prognosis. The strategies of curing benign biliary strictures could include operations and endoscopy. The stent of stric-tures parts, bilioendodraignage and the modification of strictures parts are the main treaments for benign biliary stric-tures.

Infection rate and in-hospital treatment were two prognostic factors for SAP recurrence.