Objective:To evaluate the clinical application of virtual and simulation techniques to aid pre-operative design for precise screw placement into the sustentaculum tali in the treatment of intra-articular calcaneal fractures.Methods:From January 2016 to January 2019, 68 patients were treated at Department of Orthopaedics, Suqian Hospital Affiliated to Xuzhou Medical University for intra-articular calcaneal fractures of Sanders types Ⅱ-Ⅳ. According to different designs of screw placement into the sustentaculum tali, they were assigned into a control group (38 cases and 42 feet) and an observation group (30 cases and 33 feet). There were 24 males and 14 females with an age of 39.3 years±8.8 years in the control group. There were 17 males and 13 females with an age of 42.0 years ± 7.6 years in the observation group. The control group was given a routine placement design based on the X-ray and MSCT scanning images of the injured feet. In the observation group, a Mimics model was first constructed using the X-ray and MSCT scanning images of the normal or less injured feet for further virtual screw placement into the sustentaculum tali on a 3D printed model. The disparity was investigated between the parameters designed and the actual values in both groups. The 2 groups were compared in terms of average placements, screw distribution, placement accuracy, placement time and Maryland scores of foot function one year after operation.Results:There were no significant differences in the preoperative general data between the 2 groups, showing comparability ( P>0.05). The design parameters and actual values in the control group were respectively as follows: 17.7°±3.2° versus 15.1°±5.9° in upward oblique angle, 20.3°±2.1° versus 16.2°±6.8° in backward oblique angle, and 47.9 mm ± 3.8 mm versus 45.4 mm ± 4.2 mm in length of screw path, showing significant differences ( P< 0.05). The design parameters and actual values in the observation group were as follows: 16.5°±3.5° versus 17.1°±3.9° in upward oblique angle, 20.9°±4.3° and 19.6°±3.8° in backward oblique angle, and 48.1 mm ± 3.1 mm versus 47.3 mm ± 3.8 mm in length of screw path, showing insignificant differences ( P>0.05). The average screw placements into the sustenta culum tali in the observation group (1.6±0.5) were significantly more than those in the control group (1.2±0.4). Compared with the control group, the observation group had a higher rate of placement of 2 screws[60.6 % (20/23) versus 16.7% (7/42)], higher accuracy of placement [94.3% (50/53) versus 77.6% (38/49)], less placement time for each screw (9.6 mm±3.9 min versus 13.2 mm±4.7 mm), less placement time for each foot (15.6 mm±4.8 min versus 20.5 mm±3.8 mm), and higher Maryland scores at one year after operation (94.2±6.5 versus 89.7±6.9). All the above comparisons were statistically significant ( P<0.05). Conclusions:Application of virtual and simulation techniques to aid pre-operative design for precise screw placement into the sustentaculum tali can improve the outcomes of intra-articular calcaneal fractures, because it increases the number of screws placed, enhances quality of screw placement, shortens operation time, and thus facilitates functional recovery of the injured foot.

Objective To compare the immunopotentiating effects of polysaccharides extracted from wild/cultivate Cistanehe deserticola (WCDPS/CCDPS) in Xinjiang. Methods ICR mice were subcu-taneously injected twice with different doses(low,medium and high) of WCDPS and CCDPS in combination with ovalbumin (OVA). OVA-specific antibody IgG,as well as IgG1 and IgG2a subtypes, was determined by ELISA. OVA-specific lymphocyte proliferation was measured by MTT. Expression of CD4+T and CD8+T cells was analyzed by flow cytometry. Results Both WCDPS and CCDPS could significantly improve the production of OVA-specific IgG,IgG1 and IgG2a,promote the proliferation of OVA-specific lymphocytes and increase the expression of CD4+T and CD8+T cells(all P<0.05) with no significant difference between them at the same dosages (P>0.05). WCDPS and CCDPS had no influence on the body weight of mice after im-munization. Conclusion WCDSP and CCDPS could significantly enhance the OVA-specific humoral and cellular immune responses with no statistical difference and are characterized by high safety.

Objective To investigate the correlation of the 1896 and 1899 mutations of hepatitis B virus (HBV)with the conversion of e antigen in serum and the progression of the disease. Methods 238 serum samples from the patients with HBsAg positive for over six months and HBV-DNA copy number > 5.0 × 102 IU/mL were collected,and the sequence analysis was used to analyze the nucleotide sequences of the 1896 and 1899 sites in the pre-C region of HBV. At the same time,the relevant clinical data and the expressions of HBeAg were collected,followed by Spearman correlation analysis and chi square test with SPSS 20.0. Results Both 1896 and 1899 sites in the pre-C region of HBV were mutated,and the base G was A,which was closely related to the expression of e antigen(P<0.05). Both G1896A and G1899A promoted the e antigen serological conversion ,and the e antigen serological conversion of G1899A was higher than that of G1896A. G1899A was associated with HBV related disease progression (correlation coefficient 0.280,P < 0.05),especially with the incurrence of HCC. Conclusions G1896A and G1899A in the pre-C region of HBV can promote the serological conversion of e antigen.

Objective To evaluate the value of 18F-FDG PET/CT in preoperative diagnosis and staging of suspected extrahepatic cholangiocarcinoma (EHCC).Methods The clinical data of 116 patients (72 males,44 females;age range 26-89 years) with suspected EHCC from January 2013 to October 2014 were retrospectively analyzed.All patients received preoperative whole body 18F-FDG PET/CT scan.The imaging results were compared with final clinical diagnosis.The diagnostic sensitivity,specificity,positive predictive value,negative predictive value and accuracy of 18F-FDG PET/CT were calculated.Two-sample t test was applied to compare lesion SUVmax of malignant and benign diseases.One-way analysis of variance was applied to compare SUVmax of highly,moderately and poorly differentiated tumors.x2 test was used to compare the difference of diagnostic sensitivities for hilar cholangiocarcinomas and common bile duct tumors.Results All patients were confirmed by exploratory laparotomy and subsequent histologic examination.A total of 94 cases (93 adenocarcinomas and 1 squamous carcinoma) were confirmed malignant and 22 cases (11 biliary calculi,9 cholangitis,1 choledochal cyst,1 tuberculosis) were confirmed benign.The diagnostic sensitivity,specificity,positive predictive value,negative predictive value and accuracy of 18F-FDG PET/CT for primary tumor were 61.7％ (58/94),77.3％ (17/22),92.1％ (58/63),32.1％ (17/53),64.7％ (75/116),respectively.The diagnostic sensitivity and specificity for regional lymph node metastasis were 45.5％(15/33),91.4％(53/58),and those for distant metastasis were 3/4,94.3％(82/87).The SUVmax of malignant tumors were higher than that of benign lesions (4.57± 3.75,2.72± 2.48;t =2.83,P＜ 0.05),while the differences of SUVmax among highly,moderately and poorly differentiated tumors were not significant (4.89±4.75,4.23±2.49,4.47±2.73;F=0.269,P＞0.05).18F-FDG PET/CT showed a lower sensitivity in hilar cholangiocarcinomas than that in common bile duct tumors,while no statistical significance was observed:48.6％ (17/35) vs 69.0％ (40/58),x2=3.827,P＞0.05.Conclusions The value of 18F-FDG PET/CT in preoperative diagnosis and staging of EHCC is limited.It can distinguish some benign diseases from malignant tumors,but with higher false positive for cholangitis.It can help to adjust treatment strategies by detecting distant metastasis.

OBJECTIVETo investigate the risk factor of cholecystitis after radical gastrectomy for gastric cancer.

METHODSClinicpathological data of 553 gastric cancer patients with normal gallbladders undergoing radical gastrectomy in Tianjin Medical University Cancer Institute and Hospital between March 2013 and March 2015 were analyzed retrospectively. Univariate and multivariate analysis were applied to evaluate factors influencing the cholecystitis after radical gastrectomy using log-rank and logistic regression model.

RESULTSThere were 360 males and 193 females with a median age of 60 years. All patients were followed up from 6 months to 2 years. The incidence of cholecystitis after radical gastrectomy for gastric cancer was 33.1%(183/553), while incidence of cholecystolithiasis was 4.9%(27/553). In addition, the cholecystitis incidence of patients with No.12 lymph node cleaning was 39.6%(89/225), while with No.8a lymph node cleaning was 38.0%(151/397), with No.5 lymph node cleaning was 38.0%(68/179), with No.7 lymph node cleaning was 34.4%(138/402), with No.9 lymph node cleaning was 34.7%(136/392). Univariate log-rank test indicated that the lymphadenectomy of No.8a(χ(2)=15.530, P=0.000), No.12 group(χ(2)=7.157, P=0.007) and surgical methods (χ(2)=7.427, P=0.024) were significantly associated with cholecystitis after radical gastrectomy. Multivariate analysis showed that the lymphadenectomy of No.8a was independent factor of cholecystitis after radical gastrectomy (OR=2.016, 95% CI:1.244 to 3.267, P=0.004).

CONCLUSIONSVagal nerve trunk and sympathetic ganglion should be protected carefully during No.8a lymphadenectomy in radical gastrectomy for gastric cancer, in order to reduce the incidence of postoperative cholecystitis.

Cholecystitis ; epidemiology ; Female ; Gastrectomy ; adverse effects ; Humans ; Logistic Models ; Lymph Node Excision ; Lymph Nodes ; Male ; Middle Aged ; Multivariate Analysis ; Postoperative Period ; Retrospective Studies ; Risk Factors ; Stomach Neoplasms ; surgery

Objective To measure the learning passion of medical students and evaluating its in-fluencing factors. Methods Taking 879 medical students as research subjects to conduct a questionnaire survey according to specialty and grade stratified sampling. The questionnaire contained two parts, includ-ing learning passion scale and general situation questionnaire. The effective recovery rate was 69.28%, 609 valid questionnaires were recovered. SPSS 22.0 and AMOS 21.0 software were used for statistical analysis of data, analyzing the reliability and validity of the questionnaire with internal consistency reliability coeffi-cient and confirmatory factor analysis. The factors of learning passion of medical students were analyzed by logistic regression analysis. Results The questionnaire of learning passion of medical students contained 12 measurement items, including 2 dimensions: harmonious passion and obsessive passion. The questionnaire was of fine reliability (Cronbach's Alpha=0.916) and validity (χ2/df=3.401,RMSEA=0.073,GFI=0.958). The
learning passion of medical students was at upper middle level (4.390±0.934). The influence of achievement level (OR=1.691, 95%CI=1.415 to 2.021), school satisfaction (OR=0.586, 95%CI=0.402 to 0.854) and profession plan (short-term plan OR=2.121, 95%CI=1.310 to 3.434;long-term plan OR=3.822,95%CI=1.972 to 7.405) on learning passion were statistically significant. Conclusion The questionnaire of learning pas-sion of medical students has fine reliability and validity. Achievement level, school satisfaction and profes-sion plan are factors affecting the learning passion of medical students.

Objective To investigate the relationship between biomarkers of renal function and cerebral microbleeds (CMBs) in cerebral hemorrhage patients.Methods This is a cross-sectional study including a total of 129 patients with cerebral hemorrhage.All patients underwent susceptibility weighted 3.0 T MRI.The presence and number of CMBs on susceptibility weighted MRI were independently interpreted.We calculated the urinary albumin/creatinine ratio (UACR) from morning spot urine and the estimated glomerular filtration rate (eGFR) in serum samples.Serum cystatin C (CysC) was measured using the automated particle-enhanced turbidimetric immunoassay.Results Among 129 patients with cerebral hemorrhage,86 (66.7％) had CMBs on susceptibility-weighted imaging.UACR (mg/g;20.47 ± 9.03 vs 35.24±14.83,t=3.823,P＜0.01)andCysC (mg/L;0.98±0.09vs 1.31 ±0.13,t=4.739,P＜0.01) levels were higher in the patients with CMBs than those without,and the eGFR (ml · min-1 · 1.73 m 2) was lower in the patients with CMBs than those without (78.07 ± 18.69 vs 61.59 ± 17.08,t =3.672,P ＜0.01).A Logistic regression analysis indicated that the levels of kidney impairment biomarkers were significantly associated with the prevalence of CMBs in cerebral hemorrhage patients after an adjustment for age,sex and other risk factors.The odds ratio (OR) and 95％ CI of each kidney biomarkers (eGFR,UACR,and CysC) for the CMBs status were 2.573 (1.172-5.315),2.735 (1.247-6.246)and 2.976 (1.764-6.968),respectively.CysC exhibited fair diagnostic value for CMBs,with an area under the curve of 0.835 (95％ CI 0.791-0.878).Furthermore,there were negative correlations between eGFR and the the number of CMBs (P =0.038,R2 total =0.216).There was a positive correlation between UACR,CysC and number of CMBs (P =0.024,R2 total =0.312;P =0.013,R2 total =0.375).Conclusions Elevated levels of kidney biomarkers are associated with the presence of CMBs in cerebral hemorrhage patients,independent of conventional risk factors.CysC may be a potential diagnostic biomarker for CMBs in cerebral hemorrhage patients.

ObjectiveTo analyze the clinical distribution and antimicrobial resistance profile of Serratia marcescens(S. marcescens), and to provide the scientific evidence supporting clinical diagnosis and treatment.MethodsThe antimicrobial susceptibility test was performed in 104 strains of S. marcescens by agar dilution method. The results were judged according to the criteria recommended by Clinical and Laboratory Standards Institute (CLSI) 2010.The data were analyzed by chi square test. Results The majority of S. marcescens were isolated from sputum specimens,accounting for 59.6％ (62/104). The bacteria were most frequently isolated from department of respiratory (33.7％,35/104),followed by intensive care unit (23.1％,24/104),department of gerontology (16.3％, 17/104). The results of antimicrobial susceptibility test showed that the resistance rates of S.marcescens against ampicillin,gentamicin and cephazolin were high,which were 90.4％,86.5％ and 79.8％,respectively; those against the 3rd generation of cephalosporins were 24.0％-43.3％. No imipenem and meropenem resistant strains were identified. Compared with cefoxitin-resistant strains,the resistance rates of non-cefoxitin resistant strains against piperacillin (82.9％ vs 28.6％),ceftazidime (63.4％ vs 9.5％),aztreonam (68.3％ vs 9.5％),amikacin (68.3％ vs 20.6％),ciprofloxacin (48.8％ vs 19.1％) and chloramphenicol (90.3％ vs 58.7％) were all lower (all P ＜ 0.05 ). Conclusions S. marcescens is one of the most common conditional pathogenic bacteria leading to nosocomial infections,which is resistant to many kinds of antimicrobial agents.The surveillance of antimicrobial resistance in S. marcescens should be strengthened for purpose of preventing the transmission of multidrug resistant strains.

Objective To investigate the effects of preconditioning with different doses of levothyroxine sodium on myocardial ischemia-reperfusion (I/R) injury in immature rats. Methods Forty-eight female immature Wistar rats, aged 35 days, weighing 120-140 g, were randomly allocated into 6 groups ( n = 8 each): control group (group C), I/R group, and preconditioning with levothyroxine sodium 10, 20, 40 and 80 μg/100 g groups (groups LS1-4 ) . The rats received levothyroxine sodium 10, 20, 40 and 80 μg/100 g through a gastric tube every day for 7 days in groups LS1-4 , respectively. Venous blood samples were taken on 8th day for determination of serum thyroid hormone levels. The hearts were removed from the animals and perfused in a Langendorff apparatus with K-H solution saturated with 95% O2-5% CO2 at 37 ℃. The hearts were continuously perfused for 80 min in group C. After 30 min of equilibration, the isolated hearts were subjected to 20 min of ischemia followed by 30 min of reperfusion in I/R and LS1-4 groups. HR, SP and ± dp/dtmax were recorded at 20 min of perfusion and 30 min of reperfusion. The recovery rates of HR, SP and ± dp/dtmax were calculated at 30 min of reperfusion. The coronary effluent was collected at 10 min of perfusion and 15 min of reperfusion for determination of creatine kinase (CKMB) activity. The samples of ventricular myocardial tissues were taken at 30 min of reperfusion to detect the expression of heat shock protein 70 (HSP70), thyroid hormone receptor (TR) mRNA (TRa, , TRoj and TRft ) and myosin heavy chain (MHC) mRNA. Results Compared with group C, the recovery rates of HR, SP and. ± dp/dtmax were significantly decreased, the CK-MB activity was significantly increased, and MHCα mRNA expression was down-regulated in group I/R, the recovery rates of SP and ± dp/dtmax were significantly decreased, the CK-MB activity was significantly increased, and the expression of HSP70 and MHCα mRNA was up-regulated in groups LS1-4, and the serum thyroid hormone level was significantly increased and the expression of TRa, mRNA was up-regulated in groups LS2-4 ( P ＜ 0.05) . Compared with group I/R, the recovery rates of HR and ± dp/dtmax were significantly increased, the pression of HSP70 and MHCa mRNA was up-regulated, and the MHCJ3 mRNA expression was down-regulated in groups LS1-4 the CK-MB activity was significantly decreased in groups LS1-3, and the serum thyroid hormone level was significantly increased and the expression of TRα1, mRNA was up-regulated in groups LS2-4 ( P ＜ 0.05) . The serum thyroid hormone level increased gradually with the increase in the dose of levothyroxine sodium in groups LS1-4 ( P ＜ 0.05) . The CK-MB activity was significantly higher, while the HSP70 expression lower in groups LS3-4 than in groups LS1-2 (P ＜ 0.05). Conclusion Preconditioning with levothyroxine sodium 10 μg/100 g can alleviate the myocardial I/R injury in immature rats and does not lead to the increase in the level of thyroid hormone, and the up-regulation of HSP70 and MHCa mRNA expression may be involved in the mechanism.

Objective To evaluate the preventive efficacy of oral small-dose thyroid hormone tablet premedication for a short time on euthyroid sick syndrome (ESS) in children undergoing open heart surgery under cardiopulmonary bypass (CPB) .Methods Forty ASA Ⅰ or Ⅱ children aged 3-12 yr, weighing 10-30 kg, scheduled for elective congenital heart disease surgery under CPB, were randomly allocated into 2 groups ( n = 20 each):placebo group (group P) and thyroid hormone tablet group (group T). Group T received oral thyroid hormone tablets 0.4 mg/kg every day for 4 consecutive days before surgery, while group C were given placebo. CPB was routinely established, and mild hypothermia, moderate hemodilution and high flow perfusion were adopted. Blood samples were taken from radial veins before administration (baseline) and on 1st, 2nd and 4th day after surgery to detect the serum concentrations of triiodothyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH).SP, DP and HR were recorded before administration, immediately after surgery, and on 1st and 2nd day after surgery. The endotracheal extubation time, length of ICU stay, application of positive inotropic agents and occurrence of ESS were recorded. Results No significant difference was found in hemodynamic parameters, endotracheal extubation time and length of ICU stay between the two groups ( P ＞ 0.05). As compared with the baseline values,the serum T3 levels on 1st, 2nd and 4th day after surgery, and the serum TSH levels on 1 st day after surgery were significantly decreased in the two groups, and the serum T4 levels were significantly decreased on 1 st day after surgery in group P ( P ＜ 0.05). The serum levels of T3 and T4 were significantly higher, the severity of postoperative ESS and the number of positive inotropic agent administration were significantly lower in group T than in group P (P ＜ 0.05 ). Conclusion Although oral small-dose thyroid hormone tablet premedication for 4 days (0.4 mg/kg per day) can reduce the severity of postoperative ESS, but it can not prevent the occurrence of ESS in children undergoing open heart surgery under CPB.