We amplified genes encoding UDP-glucose dehydrogenase, ecohasB from Escherichia coli and spyhasB from Streptococcus pyogenes. Both ecohasB and spyhasB were inserted into T7 expression vector pRX2 to construct recombinant plasmids pRXEB and pRXSB, and to express in E. coli BL21(DE3). After nickel column purification of UDP-glucose dehydrogenases, the enzymes were characterized. The optimum reaction condition of spyHasB was at 30 °C and pH 10. The specific activity reached 12.2 U/mg under optimum condition. The optimum reaction condition of ecoHasB was at 30 °C and pH 9. Its specific activity reached 5.55 U/mg under optimum condition. The pmuhasA gene encoding hyaluronic acid synthase was amplified from Pasteurella multocida and ligated with ecohasB and spyhasB to construct the coexpression vectors pBPAEB and pBPASB, respectively. The co-expression vectors were transformed into E. coli BW25113. Hyaluronic acid (HA) was produced by biotransformation and the conditions were optimized. When recombinant strains were used to produce hyaluronic acid, the higher the activity of UDP-glucose dehydrogenase was, the better its stability was, and the higher the HA production could reach. Under the optimal conditions, the yields of HA produced by pBPAEB/BW25113 and pBPASB/BW25113 in shake flasks were 1.52 and 1.70 g/L, respectively, and the production increased more than 2-3 folds as previously reported.
Biotransformation ; Escherichia coli ; enzymology ; Genetic Vectors ; Glucuronosyltransferase ; genetics ; Hyaluronan Synthases ; Hyaluronic Acid ; metabolism ; Pasteurella multocida ; enzymology ; Streptococcus pyogenes ; enzymology ; Uridine Diphosphate Glucose Dehydrogenase ; metabolism

Objective:To analyze the correlation between the Naples prognostic score (NPS) after preoperative neoadjuvant chemoradiotherapy in locally advanced rectal cancer (LARC) and evaluate the prognostic value of NPS in LARC.Methods:136 patients with LARC meeting the recruitment criteria from 2015 to 2020 were selected. Serum albumin, total cholesterol (TC) were collected and neutrophil-lymphocyte ratio and lymphocyte-monocyte ratio were calculated. All patients were scored and graded according to the NPS rule. The survival rate was calculated with Kaplan- Meier method. Multivariate prognostic analysis was performed by Cox models. Results:There was no significant correlation between NPS score and tumor regression or pathological complete response (pCR) of LARC patients after neoadjuvant therapy ( P=0.192, P=0.163). However, Cox multivariate analysis showed that NPS was an independent risk factor for overall survival (OS) and disease-free survival (DFS) of LARC ( P=0.009, P=0.003), and hierarchical analysis suggested that LARC patients with lower NPS score obtained better prognosis. Besides NPS, tumor size was also an independent risk factor for OS, and tumor size and N stage were the independent risk factors for DFS. Conclusion:NPS has no correlation with tumor regression or pCR for LARC after neoadjuvant chemoradiotherapy, whereas it could serve as an effective predictor for long-term prognosis of LARC.

Objective To assess the efficacy and side effects of intravesical instillation of BCG after transurethral resection of the bladder tumor (TURBT) in non-muscle invasive bladder cancer (NMIBC) patients.Methods The clinical data of patients treated with BCG 120 mg per course induced perfusion or more after TURBT from December 2013 to October 2016 in 18 hospitals of northeast China region,were analyzed retrospectively.The first part,data of 106 patients with moderate,high-risk NMIBC were collected.A total of 83 patients were male,while the other 23 patients were female.The average age was 66.7 years old.The clinical staging were T1 in 86(81.1％) cases,Ta in 20(18.9％) cases and carcinoma in situ in 6 (5.7％) patients.Intravesical instillation of BCG was executed after transurethral resection of the bladder tumor.The incidence rate of recurrence and progression during more than 6 months' follow-up time were observed.Multivariate analyses were done by using logistic analysis and Cox proportional hazards regression model with Kaplan-Meier method.The second part,treatment compliance of 276 patients with bladder cancer,including moderate/high-risk NMIBC in 263 cases,moderate/high-risk NMIBC followed with renal pelvis/ureteral carcinoma in 8 cases were and moderate/high-risk NMIBC with renal pelvis/ureteral carcinoma in 5 cases who treated with BCG after the surgeries,were observed.Patients consisted of 211 males and 65 females with average age of 68.3 years.Results With a median follow-up of 12 months,9 (8.5％) patients experienced tumor recurrence and 2 (1.9％) patients were found progression in the first part.The one-year cancer free recurrence rate of the patients was 91.5％.Statistically significant prognostic factors for recurrence identified by multivariable analyses were prior recurrence of the tumors (OR =3.214,95％CI0.804-12.845,P =0.099).In the second port,an incidence rate of adverse effects was 64.1％ (177/276).The Ⅲ/Ⅳ degree complications were occurred in 11 patients and satisfactory outcomes achieved with active treatment.A total of 36 patients withdrawal with the major causes were recurrence and progression of bladder tumor in 12 cases (4.4 ％),9 cases (3.3 ％) with economic reasons and 11 cases (4.0％) with serious complications.Conclusions NMIBC patients treated with intravesical BCG therapy have approving cancer free recurrence rates and acceptable adverse effects.Prior recurrence may be prognostic factor of recurrence after intravesical BCG therapy.

Objective:To explore the imaging changes of lung lesions in patients with imported COVID-19 when reaching the discharge standard.Methods:The clinical and CT imaging data of 60 cured patients with imported COVID-19 and discharged from January to February 2020 in Anhui Province were retrospectively collected. At the initial diagnosis, 5 cases were mild, 53 were ordinary, and 2 were severe. The clinical characteristics of the patients and the characteristics of chest CT images at discharge were analyzed.Results:Fever (57 cases) and cough (55 cases) were the main symptoms in 60 patients. In 5 mild patients, 3 cases were negative in the whole course of CT examination, 2 cases were negative in the first time and abnormal in the second time. The first CT imaging features of 55 patients (53 common type and 2 severe type) were mainly bilateral lung involvement (51 cases), multiple lesions (33 cases), more common under the pleura (40 cases), and ground glass opacities were the most common (55 cases). The features of chest CT in clinical outcomes were that the ground glass shadow in the lung gradually faded and was completely absorbed (19 cases); the scope of ground glass shadow in the lung expanded and progressed to crazy-paving, consolidation shadow, and the lesion gradually absorbed again followed by fibrous cord shadows (27 cases); ground-glass opacities in the lungs quickly progressed to a consolidation and then slowly absorbed. Most of the lesions were accompanied by more residual fibrous cord shadows (4 cases). In 2 severe patients, the lesions in the lungs were larger ground glass, and a large amount of fibrous foci remained after slow absorption.Conclusions:Chest CT plays an important role in the diagnosis and treatment of imported COVID-19, and the degree of lung involvement seen on CT images is in good agreement with clinical outcome.

Objective: To explore the imaging changes of lung lesions in patients with imported COVID-19 patients when reaching the discharge standard. Method: The clinical and CT imaging data of 60 patients with imported COVID-19 cured and discharged from January to February 2020 in Anhui Province were retrospectively collected. The clinical characteristics of the patients and the characteristics of chest CT images at discharge were analyzed. Results: Fever (57 cases) and cough (55 cases) were the main symptoms in 60 patients. At the initial diagnosis, 5 cases were mild, 53 were ordinary, and 2 were severe. In 5 light patients, 3 cases were negative in the whole course of CT examination, 2 cases were negative in the first time and abnormal in the second time. . The first CT imaging features of 55 patients (53 common type and 2 severe type)were mainly bilateral lung involvement (51 cases), multiple lesions (33 cases), more common under the pleura (40 cases), and ground glass opacities were the most common. (55 cases). The clinical features of chest CT in clinical outcomes are that the ground glass shadow in the lung gradually fades and was completely absorbed (19 cases); the scope of ground glass shadow in the lung expanded and progressed to crazy-paving, consolidation shadow, and the lesion gradually absorbs again followed by Fibrous cord shadows (27 cases); ground-glass opacities in the lungs quickly progressed to a consolidation and then slowly absorbed . Most of the lesions were accompanied by more residual fibrous cord shadows (4 cases). In 2 severe patients, the lesions in the lungs were larger ground glass, and a big amount of fibrous foci remained after slowly absorption. Conclusion Chest CT plays an important role in the diagnosis and treatment of imported COVID-19, and the degree of lung involvement seen on CT images is in good agreement with clinical outcome.