Objective:To explore the spatial support capacity and its influence in osteogenic effect of composite biofilm based on poly(propylene carbonate)(PPC)/poly(butylene succinate)(PBS)in rabbit tibial bone defect models,and to clarify its barrier functional reliability and osteogenetic effect in vivo.Methods:The composite biofilms of PPC/PBS and PPC/PBS/collegen type Ⅰ(Col-Ⅰ)(PPC/PBS/Co)were prepared.Eighteen Japanese big-ear rabbits were selected and two bone defects were prepared on each side of the tibia of the rabbits.Six rabbits were randomly selected to place PPC/PBS composite biofilm on the bone defects,2 rabbits were executed at 2,4,8 and 12 weeks after operation,and the surface microstructures of PPC/PBS composite biofilm in the rabhit bone defect area were observed by scanning electron microscope(SEM).The experiment was divided into blank control group,PPC/PBS composite biofilm group,BME-10X collagen membrane group,and PPC/PBS/Co composite biofilm group.The above biofilms were placed on the corresponding bone defects of rabbits by operation,while no biofilm was placed in the rabbits in blank control group.Three rabbits were killed at 2,4,8 and 12 weeks after operation respectively,and the gray values of regenerated bone in the bone defect areas of the rabbits in varrous groups were detected by soft X-ray;the fluorescence intensities of regenerated bone tissue in the bone defect areas of the rabbits in various groups were observed by laser scanning confocal microscope after fluorescence labeling.The pathomorphology of regenerated bone tissue in the bone defect areas of the rabbits in various groups were observed by HE staining and modified Gomori staining,and the expression levels of bone morphogenetic protein 2(BMP-2)and osteopontin(OPN)in the regenerated bone tissue in bone defect areas of the rabbits in various groups were detected by immunohistochemical staining.Results:In general,the PPC/PBS composite biofilm was tightly covered in the bone defect area without displacement and collapse.The SEM results showed that the porous surface of PPC/PBS composite biofilm appeared micropore structure and the number of micropores was increased with the prolongation of time,while the smooth surface of biofilm basically did not form the micropore-like structure.The results of soft X-ray detection showed that the gray values of regenerated bone tissue in bone defect areas of the rabbits in various groups were increased with the prolongation of time,and the gray value of regenerated bone tissue in bone defect areas of the rabbits in PPC/PBS/Co composite biofilm group was significantly higher than those in other groups(P＜0.05).The confocal micrscope results showed that the fluorescence intensity of regenerated bone tissue in bone defect areas of the rabbits in PPC/PBS/Co composite biofilm group was similar to those in blank control group at 4,8,and 12 weeks;compared with PPC/PBS composite biofilm group and BME-10X collagen membrane group,the fluoresence intensity of regenerated bone tissue in bone defect areas of the rabbits in PPC/PB/Co composite biofilm group at 4 weeks was increased(P＜0.05),and the fluoresence intensity of regenerated bone tissue in bone defect areas of the rabbits at 8 and 12 weeks were decreased(P＜0.05).The results of HE staining and modified Gomori staining showed that compared with PPC/PBS composite biofilm group and BME-10X collagen membrane group,the new bone formed faster in PPC/PBS/Co composite biofilm group and blank control group at 2 and 4 weeks,and the lamellar bone mineralization was higher at 12 weeks.The immunohistochemical staining results showed that compared with blank control group,PPC/PBS composite biofilm group and BME-10X collagen membrane group,the expression levels of BMP-2 and OPN proteins in the regenerated bone tissue in bone defect areas of the rabbits in PPC/PBS/Co composite biofilm group at 2 and 4 weeks were increased(P＜0.05 or P＜0.01);compared with blank control group and PPC/PBS composite biofilm group,the expression levels of BMP-2 and OPN proteins in the regenerated bone tissue in bone defect areas of the rabbits in BME-10X collage membrane group were decreased(P＜0.05 or P＜0.01).Conclusion:PPC/PBS composite biofilm has excellent spatial support capacity and reliable physical barrier function.The PPC/PBS/Co composite biofilm has a good effect in guiding bone regeneration in vivo.

Objective:To prepare the control materials of point-of-care(POC) glucose testing and evaluate their homogeneity, stability and matrix effects.Methods:The high, medium and low concentration control materials were prepared from patient leftover whole blood, which was centrifuged, fixed, washed, filtered, and aliquoted. The homogeneity and stability of the control materials were evaluated according to CNAS (China National Accreditation Service for Conformity Assessment, CNAS) GL29:2010"Reference materials-General and statistical principles for certification". The control materials were used to evaluate the matrix effects in POC glucose detection systems by Deming regression, according to the Clinical and Laboratory Standards Institute (CLSI) EP14-A3. Meanwhile, these control materials were used as the internal quality control, and their coefficients of variation ( CV) were calculated. One-way ANOVA and t-Test were used to analyze the results. Results:The homemade materials at three concentrations showed good homogeneity[ F< F0.05(9, 20)]. When the control materials were stored at 2-8 ℃, the stable phases for the opened and closed bottles were 10 days and 15 days, respectively, and there was no statistically significant difference between the results of the first day( P>0.05). The control materials at three concentrations also showed good applicability and there were no matrix effects in 10 POC glucose systems. When the control materials were detected in the internal quality control, the CVs of the high, medium and low concentrations were 0.63%, 0.66% and 1.65%, respectively, which were all below 7.5%. Conclusions:The homemade human control materials of POC glucose testing showed good homogeneity, stability and applicability. They met the requirements of quality control in hospital settings, which provided a good application prospect of the quality management of POC glucose testing.

Objective:To detect the mRNA expression and methylation status of leucine rich repeat containing 55(LRRC55) gene in pancreatic carcinoma tissues, and discuss the clinical value.Methods:Resected pancreatic ductal adenocarcinoma and normal adjacent specimens from 37 patients admitted in General Surgery of First Affiliated Hospital of Naval Medical University were collected from May 2019 to May 2021. Another two normal pancreas specimens and two blood samples from healthy adults were also collected. All patients′ age, gender, tumor location, tumor size, tumor differentiation, TNM staging, lymphatic metastasis, CEA and CA19-9 level were recorded. Bisulfite treatment of genomic DNA and sequencing analysis was used to study methylation patterns in CpG islands of the promoter for LRRC55 gene in fresh tissues from 2 pancreatic adenocarcinoma and adjacent tissues, 2 normal pancreatic tissues, 2 pancreatic cancer cell lines (PaTu8988 and ASPC1). LRRC55 mRNA in 35 pancreatic adenocarcinoma and adjacent tissues was detected by real-time quantitative PCR and the correlations with clinical parameters were analyzed.Results:CpG islands of LRRC55 in pancreatic adenocarcinoma tissues and pancreatic cancer cell lines was highly methylated and the mean methylation rate was 53% and 71%, respectively; while LRRC55 gene in pancreatic adjacent tissues and normal pancreatic tissues was lowly methylated, and the mean methylation rate was 8% and 11%. The relative expression in the pancreatic adenocarcinoma tissues and the paired adjacent normal tissues was 0.21 (0.02, 1.00 ) and 0.98 (0.33, 3.66 ), respectively; the former was significantly lower than the later and the difference was statistically significant ( P=0.003). Correlation analysis showed that LRRC55 mRNA expression level was related to tumor differentiation and CEA, but not correlated with patients′ age, gender, tumor location and size, CA19-9 level, lymphatic metastasis and TNM staging. Conclusions:Pancreatic cancer tissue and cell lines had abnormal methylation of LRRC55 gene; LRRC55 gene hypermethylation was related with its lower mRNA expression level in pancreatic cancer, which was correlated with the tumor differentiation and CEA level. LRRC55 may be a potential suppressor gene for pancreatic cancer.

【Objective】 To analyze the impact of sporadic cases of COVID-19 on the work of Transfusion Department, so as to explore the countermeasures. 【Methods】 The admission of inpatient departments, the reception of outpatient(including emergency) departments, the workload of transfusion department(including blood typing, unexpected antibody screening and cross matching), and the consumption of blood components in the Xijing Hospital between October and November in 2021, during COVID-19 outbreak, were collected. All the above data was statistically compared to the data in same period in 2018, before the COVID-19 outbreak. 【Results】 Due to the COVID-19 epidemic, there was a significant decrease in number of inpatients(280±157.1 vs 340.4±110.2), outpatient(including emergency)(8 359±3 615 vs 10 151±3 225), the workload of blood typing(272.0±132.4 vs 341.6±110.4), unexpected antibody screening(78.26±42.22 vs 98.51±43.53) and crossmatch(237.2±99 vs 475.7±155.6), as well as the consumption(U) of all blood components(457.9±50.32 vs 579.4±62.51) in the Xijing Hospital(P<0.05). In detail, the epidemic had the most direct impact on the number of inpatients and outpatients, which shrank continuously on the 2^nd day after official announcement of the new COVID-1 cases. While the workload of blood typing, unexpected antibody screening and crossmatch decreased slightly, with a lag, usually on the 2^nd, 3^rd and 5^th day after official announcement. The decrease of the usage of red blood cells and plasma began from the 7^th day after the new epidemic to the 6^th day after the end of the epidemic. However, the usage platelets and cryoprecipitate coagulation factors decreased from the 8^th and 10^th day after the new epidemic to the 2^nd and 6^th day after the end of the epidemic, respectively. 【Conclusion】 The daily work of Blood Transfusion Department has been seriously affected by sporadic COVID-19 epidemic. The working mode, staff structure and inventory ratio of blood components should be adjusted and optimized instantly to maintain the normal conduct of medical treatments in hospitals and ensure the safety of patients.

The present study was conducted to clarify the therapeutic effect of cornuside on experimental autoimmune encephalomyelitis (EAE) and its influence on T helper 17 (Th17) cell and regulatory T (Treg) cell infiltration into the central nervous system. Rats were randomly placed into four treatment groups: control, EAE, EAE+cornuside, and EAE+prednisolone. The neurological function scores of rats were assessed daily. On the second day after EAE rats began to show neurological deficit symptoms, the four groups were treated with normal saline, normal saline, cornuside (150 mg/kg), and prednisolone (5 mg/kg), respectively. The treatment was discontinued after two weeks, and the spinal cord was obtained for hematoxylin and eosin (H&E) and luxol fast blue staining, as well as retinoic acid receptor-related orphan receptor γ (RORγ) and forkhead box protein P3 (Foxp3) immunohistochemical staining. Blood was collected for Th17 and Treg cell flow cytometry testing, and the serum levels of interleukin (IL)-17A, IL-10, transforming growth factor-β (TGF-β), IL-6, IL-23, and IL-2 were measured via enzyme-linked immunosorbent assay (ELISA). Compared with rats in the EAE group, rats in the EAE+cornuside and EAE+prednisolone groups began to recover from neurological deficits earlier, and had a greater degree of improvement of symptoms. Focal inflammation, demyelination, and RORγ-positive cell infiltration were reduced by cornuside or prednisolone treatment, whereas the Foxp3-positive cell numbers were not significantly different. Meanwhile, the number of Th17 cells and the IL-17A, IL-6, and IL-23 levels were lower in the blood after cornuside or prednisolone treatment, whereas the number of Treg cells or the levels of IL-10, TGF-β, and IL-2 were not markedly different. Cornuside can alleviate symptoms of EAE neurological deficits through its anti-inflammatory and immunosuppressive effects, and Th17 cells may be one of its therapeutic targets.

Objective:To discuss the application and effectiveness of the flipped classroom based on Wechat platform in the teaching of neurology.Methods:clinical students of grade 2014 of binjiang college of Zhejiang Chinese Medical University were selected as teaching subject. The students were divided into experimental group which contained a total of 74 students in class one and class three and the control group which contained a total of 38 students in class two. Peripheral neuropathy and neuromuscular-junction disease were selected as teaching contents. The experimental group adopted flipped classroom as the teaching mode and Wechat platform for pre-class preparation, after-school review and interactive communication. The control group was taught by traditional teaching mode. Before and after class, students in the two groups had a small-scale test and were surveyed by questionnaire, respectively. Students in the two groups took the same final exam which included case analysis when the course was over. The scores of the final exam and the results of the case analysis of each group were recorded and analyzed. All data were processed with statistical software SPSS 20.0, and t-test or chi-square test was used. Results:Students in the experimental group had significantly higher test scores in the after-class small-scale test than those in the control group ( P=0.038). Their final exam scores were higher than those in the control group ( P=0.046), and their scores of case analysis in the final exam were higher than those in the control group ( P=0.026). The results of pre-class questionnaire survey showed that the proportion of students who chose "good" in the experimental group was higher than that in the control group on the understanding of the learning content and the preparation ( P<0.05). In the after-class questionnaire survey, the proportion of students who chose "excellent" and "good" in the evaluation of learning interest in the experimental group was higher than those in the control group ( P<0.05), the proportion of students in the experimental chose "good" in evaluating their self-learning ability was higher than that in the control group ( P<0.05), the proportion of "excellent" on clinical thinking ability and teaching satisfaction was higher in the experimental group than that in the control group ( P<0.05), and the overall proportion of students who chose "excellent" and "good" in all items in the experimental group were higher than that in the control group ( P<0.05). In the experimental group, the overall proportion of students who selected "excellent" and "good" in on the evaluation of their learning interest was significantly increased in the after-class questionnaire survey compared with the pre-class questionnaire survey ( P<0.01). Conclusions:The application of flipped classroom based on Wechat platform is feasible and effective in the teaching of neurology. It can make up for the deficiency of traditional teaching methods. It is helpful to improve students' learning interest and self-learning ability, and is also helpful to exercise their clinical thinking ability. Thus this method deserves further popularization.

In this study,thermosensitive and repairable molecularly imprinted solid-phase microextraction fibers were synthesized using spiramycin as template molecule,methacrylic acid and N-isopropylacrylamide as functional monomers,ethylene glycol dimethacrylate as crosslinking agent,and silanized quartz capillary as carrier. The prepared molecularly imprinted solid-phase microextraction fibers were characterized by scanning electron microscope and nitrogen adsorption/desorption,and various parameters affecting the extraction efficiency were optimized. Due to high selectivity and sensitivity of the fibers for macrolide antibiotics,the quantitative analysis of four macrolide antibiotics in food matrix,spiramycin,tilmicosin,tylosin,and josamycin,was peroformed in combination with high performance liquid chromatography. In the range of 0.5 to 50 μg/mL,the chromatographic peak area showed a good linear relationship with the concentration. The spike recoveries of the samples at three different addition levels were between 81.8% and 119.1%;the inter-day precisions were less than 13.8% (n=6),and the intra-day precisions were less than 15.5% (n=3).

Objective To investigate the clinical efficacy of total pancreaticoduodenectomy combined with portal vein resection and allograft vascular grafts for pancreatic cancer with vascular invasion.Methods The retrospective and descriptive study was conducted.The clinicopathological data of 9 patients with pancreatic cancer who underwent total pancreaticoduodenectomy combined with portal vein resection and allograft vascular grafts in the Beijing Chao Yang Hospital of Capital Medical University from January 2014 to September 2016 were collected.There were 4 males and 5 females,aged from 53 to 78 years,with a median age of 60 years.Involvement of portal vein (PV) and (or) superior mesenteric vein (SMV),splenic vein or convergence was detected in patients by preoperative evaluation,which indicated borderline resectable pancreatic cancer.Patients underwent complete surgical resection of tumor and involved portal veins,and then underwent vascular and digestive tract reconstruction.Observation indicators:(1) intraoperative situations;(2) postoperative situations;(3) follow-up.Patients were followed up by telephone interview and outpatient examination to detect survival of patients up to October 2018.Measurement data with normal distribution were represented as Mean±SD,measurement data with skewed distribution were expressed as M (range),and count data were expressed as absolute number.Results (1) Intraoperative situations:9 patients underwent total pancreaticoduodenectomy combined with portal vein resection and allograft vascular grafts successfully,including 1 undergoing total pancreaticoduodenectomy due to positive margin of pancreatic neck during pancreatico-duodenectomy for pancreatic head carcinoma,3 of pancreatic head carcinoma with portal vein involvement and atrophy of pancreatic body and tail,and 5 of carcinoma of pancreatic neck and body with portal vein involvement.The operation time,portal vein occlusion time,and volume of intraoperative blood loss were (573± 19) minutes,(21 ±4) minutes,and (717±33) mL.(2) Postoperative situations:4 of 9 patients had postoperative complications,including 2 with grade Ⅰ complication and 2 with grade Ⅱ complication.There was no grade Ⅲ or above complication.No anastomotic stenosis or thrombus formation after reconstruction for portal vein.The perioperative complications were cured after conservative treatment.Duration of postoperative hospital stay was 17 days (range,10-25 days).Nine patients underwent subcutaneous injection of insulin to control blood glucose during the period fasting for solids and liquids.After resuming the semi-liquid diet of diabetes,patients received subcutaneous injection of rapid acting insulin before meals combined with subcutaneous injection of long-acting insulin before bedtime,with a insulin need of 24-36 U/d.Patients had postprandial blood sugar level of 8-11 mmol/L,without unmanageable hyperglycemia orlong-term application of insulin pump.Patients received oral trypsin pancreatin instead of trypsin,with no gastrointestinal symptoms such as bloating and steatorrhea,no malnutrition.Of 9 patients,2 had well-differentiated adenocarcinoma,4 had moderately differentiated adenocarcinoma,and 3 had poor-differentiated adenocarcinoma.There were 3 patients with no vascular invasion,1 with endangidic invasion,5 with tumor infiltration of tunica adventitia vasorum.One of 9 patients was in IIA stage of TNM staging,3 were in the II B stage,and 5 were in IIIB stage.The negative rate of pathological sections for excised specimen margin was 8/9.(3) Follow-up:9 patients were followed up for 7-37 months,with a median follow-up time of 15 months.Four patients survived,4 died of tumor recurrence and metastasis,and 1 died of cerebrovascular accident.Conclusion Total pancreaticoduodenectomy combined with portal vein resection and allograft vascular grafts is safe and feasible for pancreatic cancer involving portal vein,splenic vein or junction.

Objective To summary the pathological and clinical characteristics,treatments and prognosis of malignant renal perivascular epithelioid cell tumor (PEComa).Methods Between August 2013 and June 2017,8 cases of malignant renal PEComa were analysed respectively.Of all the patients,there were 4 males and 4 females,aged 27-65 years with the average of 46.3 years old.Three cases were detected in routine examination occasionally,three cases complained of intermittent back pain with fever,one presented with swollen and painful right hand and right foot,and one case presented with hematuria.CT or MRI examinations indicated the malignant lesions before the surgery.Clinical staging was performed with 2 cases of T1N0M0,1 case of T1 N0M1,2 cases of T2N0M0,1 case of T3M0M0,and 2 cases of T4N0M1.Three cases underwent radical nephrectomy,1 case underwent radical nephrectomy plus renal artery embolization,2 cases underwent partial nephrectomy,and 2 cases underwent nephrectomy plus inferior vena cava tumor thrombectomy.One case was treated with ifosfamide plus epirubicin after operation due to multiple distant metastases and 1 case was treated with oxaliplatin before the sugery because of excessive tumor diameter.None of the rest received any adjuvant therapy.Results Postoperative histopathological examination showed multiple nodules in reddish gray and yellow color,with soft texture and partial incomplete capsule.Microscopically,there were large atypical cell components,some of which were spindle shaped,with disordered cell arrangement,some of which were associated with a large amount of necrotic tissue,and abundant light eosinophil cytoplasm.Tissue components can be found thick-wall blood vessels,smooth muscle-like cells,and adipose tissue.Immunohistochemistry showed 4 cases were positive of HMB-45,4 of Melan-A,7 of SAM.Seven cases were negative of CK,6 of S-100 75％ (6/8) and Ki67 (10％-70％).Two cases died of multiple metastases (lung,bone,liver),1 case survived with tumor recurrence,with a follow-up from 14 to 60 months (mean 29 months).Conclusions Primary malignant renal PEComa is rare in practice with relative large diameter.The diagnosis depends on pathological findings,and radical nephrectomy is the first choice of treatment.It is easy to recur and metastasize after the operation.

Objective To explore the CRP harmonization by calibration using commutable trueness verification materials. Methods High and low level of CRP concentrations trueness verification materials(H and L) were prepared by Beijing center for clinical laboratories. Thesetrueness verification materials were diluted to 5 calibration points(5L, 4L+1H, 3L+2H, 1L+4H, 5H) by weighing method, respectively. These 5 points were used to calibrate four different brands of CRP detection system (Diasys, Leadman, Siemens and Roche) instead of the original procedure. Sera from 21 patients and the international standard ERM DA-474/IFCC were used to compare harmonization and trueness after calibration. Each sample above was measured twice. Results After calibration, the median of CV was reduced from 19.33％ to 2.92％ among 21 patient samples, less than the optimal CV based on biological variability (CV=10.6％). Compared with Desai, the slopes were closer to 1 from 0.90-1.09 to 0.93-0.96 after calibration. Meanwhile, if ERM-DA474/IFCC was used as the trueness verification materials, the absolute bias wasreduced from 3.08-11.07 mg/L to 0.52-2.97 mg/L which was close to theuncertainty of itself (2.5 mg/L). Conclusions Afterthe calibration which contained five linear concentration points of CRP trueness verification materials by weighing method, both harmonization and trueness of CRP were improved.