The amino acid sequences of the OmpA protein isolated from Escherichia coli QML2206-1(E.coli QML2206-1)in our laboratory were analyzed for homology with different strains of OmpA proteins using bioinformatics software,and the OmpA protein was analyzed for its physicochemical properties,transmembrane structure and signal peptide prediction,B-cell anti-genic epitope prediction,secondary and tertiary structure prediction.The OmpA gene fragment was ligated with pET-32a vector to construct a prokaryotic expression vector,which was purified by a nickel column affinity purification system after prokaryotic expression and optimization of ex-pression conditions in BL21(DE3).The purified recombinant protein was fully mixed with Freund's adjuvant to immunize mice,and the levels of mouse-specific IgG antibody and the expression levels of cytokines CD4,CD8 and IL-4 in mouse serum were detected by ELISA,and the immuno-protective effect was evaluated by mouse attack protection test.OmpA protein is a hydrophilic protein with no transmembrane structural domains and a secondary structure consisting mainly of irregular coils(47.98％)and α-helices(29.77％),with 12 antigenic epitopes that can bind to anti-bodies produced by B cells.The recombinant protein OmpA with a relative molecular mass of a-bout 55 kDa was successfully obtained by prokaryotic expression,and the highest expression was induced by IPTG concentration of 0.000 4 mmol/L for 6 h at 37 ℃.The serum-specific IgG anti-body potency of recombinant protein immunized mice was up to 1∶32 000;the expression levels of CD4,CD8 and IL-4 in the serum of immunized mice were elevated compared with those of the con-trol group.The survival rate of mice was 80％and 40％after attack with minimum lethal dose(MLD)and 2 times minimum lethal dose(2MLD),respectively.OmpA recombinant protein has good antigenicity and certain immunoprotective effects,and this study provides a technical basis for the next step in the development of a genetically engineered subunit vaccine against yak-appli-cable E.coli based on OmpA protein.

The amino acid sequences of the OmpA protein isolated from Escherichia coli QML2206-1(E.coli QML2206-1)in our laboratory were analyzed for homology with different strains of OmpA proteins using bioinformatics software,and the OmpA protein was analyzed for its physicochemical properties,transmembrane structure and signal peptide prediction,B-cell anti-genic epitope prediction,secondary and tertiary structure prediction.The OmpA gene fragment was ligated with pET-32a vector to construct a prokaryotic expression vector,which was purified by a nickel column affinity purification system after prokaryotic expression and optimization of ex-pression conditions in BL21(DE3).The purified recombinant protein was fully mixed with Freund's adjuvant to immunize mice,and the levels of mouse-specific IgG antibody and the expression levels of cytokines CD4,CD8 and IL-4 in mouse serum were detected by ELISA,and the immuno-protective effect was evaluated by mouse attack protection test.OmpA protein is a hydrophilic protein with no transmembrane structural domains and a secondary structure consisting mainly of irregular coils(47.98％)and α-helices(29.77％),with 12 antigenic epitopes that can bind to anti-bodies produced by B cells.The recombinant protein OmpA with a relative molecular mass of a-bout 55 kDa was successfully obtained by prokaryotic expression,and the highest expression was induced by IPTG concentration of 0.000 4 mmol/L for 6 h at 37 ℃.The serum-specific IgG anti-body potency of recombinant protein immunized mice was up to 1∶32 000;the expression levels of CD4,CD8 and IL-4 in the serum of immunized mice were elevated compared with those of the con-trol group.The survival rate of mice was 80％and 40％after attack with minimum lethal dose(MLD)and 2 times minimum lethal dose(2MLD),respectively.OmpA recombinant protein has good antigenicity and certain immunoprotective effects,and this study provides a technical basis for the next step in the development of a genetically engineered subunit vaccine against yak-appli-cable E.coli based on OmpA protein.

Hemodynamics plays a vital role in the development and progression of cardiovascular diseases, and is closely associated with changes in morphology and function. Reliable detection of hemodynamic changes is essential to improve treatment strategies and enhance patient prognosis. The combination of computational fluid dynamics with cardiovascular imaging technology has extended the accessibility of hemodynamics. This review provides a comprehensive summary of recent developments in the application of computational fluid dynamics for cardiovascular hemodynamic assessment and a succinct discussion for potential future development.

Objective To elucidate the influence of two procedures aortic root remodeling using a straight tubular artificial vessel while preserving the aortic valve and the Florida sleeve procedure on the biomechanics of the aortic root.Methods Five finite element models of the aortic root were reconstructed using computed tomography angiography images,including two cases of aortic root remodeling(A1 and A2),two cases of the Florida sleeve procedure(B1 and B2),and one control group without aortic root pathology(C).Numerical simulations were performed to obtain the blood flow and pressure distribution result to assess the differences in the hemodynamics of the aortic root.Results There were no significant differences in the peak systolic velocity between the two procedures and the control.However,the flow velocity after aortic root remodeling was smoother,similar to the model of the control group,with a more stable average aortic pressure and wall shear stress.In the Florida sleeve procedure,high-speed blood flow affected the vessel wall,leading to various degrees of wall shear stress and pressure concentrations along the aortic wall.Conclusions After aortic root replacement with valve preservation,blood flow patterns in the reconstructed aortic root depended on postoperative changes in sinus geometry.Both surgical procedures showed favorable blood flow patterns;however,the flow pattern after aortic root remodeling was more stable than that after the Florida sleeve procedure.

Objective: To identify the associated factors of peripheral blood lymphocyte counts (PBLC) in gastric cancer patients Methods: In this cross⁃sectional study , data were collected from patients underwent gastric cancer surgery. Univariate analysis , multiple linear regression and variable importance metrics were used to assess factors associating PBLC in pre⁃operative patients. The findings were further investigated by fitting locally weighted regression(loess) and robust linear model (rlm) . Results: Patients with pre⁃operative PBLC < 1 . 1 × 109/L( group A) were 138(20. 72% ) , whereas patients with PBLC ≥ 1. 1 × 109/L ( group B) were 528(79. 28% ) . Compared to group B , patients in group A were older[(64. 61 ± 10. 42 years) vs (62. 18 ± 10. 41 years) , P < 0. 05 ] and showed lower neutrophils [(3. 21 ± 1. 41) × 109/L vs (3. 59 ± 1. 31) × 109/L , P < 0. 01] . Lymphopenia was associated with later stage of gastric cancer, P < 0. 01 . A multiple linear regression model with randomly distributed residuals found that age ( β = - 0. 01 , t = - 3. 70 , P < 0. 01) and tumor stage [ β ( Ⅱ vs Ⅰ ) = - 0. 16 , t =- 2. 79 , P < 0. 01 ; β ( Ⅲ vs Ⅰ ) = - 0. 18 , t = - 3. 86 , P < 0. 01 ; β ( Ⅳ vs Ⅰ ) = - 0. 21 , t = - 2. 16 , P <0. 05] were to be statistically significant factors for lymphopenia. Neutrophil increase (β = 0. 05 , t = 3. 61 , P < 0. 01) was associated with a higher PBLC. The relative importance analysis for continuous independent variables showed that relative importance metric LMGs in variable age , neutrophil and CEA were 55. 55% , 44. 14% and 0. 31% respectively. Loess and rlm models showed that age was the negatively influencing factor of PBLC. Conclusion PBLC in gastric cancer patients were positively associated with neutrophils , and negatively associated with age and tumor stages.

Objective To construct and appraise a new model for predicting the prognosis of rectal cancer patients using the Lasso-Cox strategy.Methods The clinical pathological data of 599 rectal cancer patients who underwent radical resection were analyzed.Comparison between groups,Lasso and Cox regression were used to select varia-bles and construct a model,and its discrimination,consistency,and clinical benefits were appraised by the receiv-er operating characteristic(ROC),calibration curve,and decision curve analysis.Results Comparison between groups showed that age,body mass index(BMI),preoperational nutrition status,carbohydrate antigen199(CA199),preoperative chemotherapy,intraoperative blood transfusion,vascular or nerve invasion,cancer nod-ules,pathologic T,N,and TNM stages,tumor recurrence or metastasis,radiotherapy and postoperative survival time were associated with grouping of death or survival in rectal cancer patients.Among them,8 variables were se-lected by lasso and contained into the Cox regression model.Age(HR=1.04,P＜0.05),BMI(HR=0.89,P＜0.05),blood transfusion(HR=2.29,P＜0.05),postoperative chemotherapy(HR=0.16,P＜0.01),recur-rence(HR=43.67,P＜0.01),and metastasis(HR=2.75,P＜0.05)were identified as independent prognostic factors,which were used to construct a nomogram model.The area under the curve(AUC)and the 95％confi-dence interval of the receiver operating characteristic(ROC)curve of the predictive model was 0.95(0.91-0.99),P＜0.01.The predicted probability of 1-year and 3-year survival was close to the actual probability.The DCA curve of the model was far away from a decision line parallel to the X-axis and another line with a negative slope.Conclusion The newly established nomogram has good discrimination,consistency and clinical benefits,which help predict the prognosis of rectal cancer after surgery.

Objective To explore and compare the efficacy of open reduction Kirschner-wire internal fixation and closed reduction Herbert screw internal fixation in the treatment of fresh unstable scaphoid lumbar fracture.Methods 72 patients with fresh unstable scaphoid lumbar fracture admitted to our hospital from January 2020 to January 2022 were selected and randomly divided into the experimental group(36 cases,open reduction Kirschberg wire internal fixation)and the control group(36 cases,closed reduction Herbert screw internal fixation).The operation time,fracture healing time,healing rate at 12 weeks,complication rate,scaphoid osteonecrosis rate,wrist functional recovery 6 months and 1 year after surgery were observed and compared within 2 groups,including wrist range of motion,improved Mayo wrist function score,pain index using visual analog scale(VAS).Results There were no significant differences in operation time,fracture healing time,healing rate and complication rate in 2 groups(P＞0.05).6 months after surgery,the wrist motion of ulnar deviation,radial deviation,dorsalis extension and palmaris flexion in 2 groups were significantly improved compared with before surgery(P＜0.05).There was no significant difference in wrist motion in 2 groups after surgery(P＞0.05).Compared with 6 months after surgery,Mayo score of experimental group was significantly improved at 12 months after surgery(95.36± 3.34)vs.(78.52±5.62)(P＜0.05),and VAS was significantly decreased(1.04±2.24)vs.(3.25± 1.62)(P＜0.05),but there was no significant difference in Mayo score and VAS between 2 groups(P＞0.05).Conclusions Compared with closed reduction and Herbert screw internal fixation,open reduction and Kirschner wire internal fixation can also achieve satisfactory results.However,the operation cost and difficulty of Kirschner wire internal fixation are relatively low.