This study aimed to explore the value of magnetic resonance imaging (MRI) T 2 mapping in the assessment of dermatomyositis (DM) and polymyositis (PM). Thirty-three confirmed cases (myosin group) and eight healthy volunteers (healthy control group) at the Department of Rheumatology and Immunology, the First Affiliated Hospital of Kunming Medical University, from October 2016 to December 2017, were collected and analyzed. Multiple parameters of the myosin group were quantified, including creatine kinase (CK), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), complement C3, and complement C4. Disease status was evaluated using a panel of tools: myositis disease activity assessment tool-muscle (MDAAT-muscle), myositis disease activity assessment tool-whole (MDAAT-all), health assessment questionnaire (HAQ), medical outcomes study health survey short form-36 item (SF-36), hand muscle strength test (MMT-8) score, and MRI T 2 mapping of muscle (22 muscles in the pelvis and thighs) T 2 values. The results showed that in the myositis group, the measurements for CK, ESR, CRP, complement C3, and complement C4 were 457.2 (165.6, 1 229.2) IU/L, 20 (10, 42) mm/1h, 3.25 (2.38, 10.07) mg/L, 0.90 (0.83, 1.06) g/L, and 0.18 (0.14, 0.23) g/L, respectively. The scores for MMT-8, MDAAT-muscle, MDAAT-all, HAQ, and SF-36 were 57.12±16.23, 5.34 (4.00, 6.00), 34.63±12.62, 1.55 (0.66, 2.59), and 44.66±7.98, respectively. T 2 values were significantly higher in all 22 muscles of the pelvis and thighs of patients with DM or PM compared with the healthy controls [(54.99±11.60)ms vs. (36.62±1.66)ms, P<0.001], with the most severe lesions in the satrorius, iliopsoas, piriformis, gluteus minimus, and gluteus medius muscles. The total muscle T 2 value in the myositis group was positively correlated with CK, MDAAT-muscle, MDAAT-all, and HAQ ( r=0.461, 0.506, 0.347, and 0.510, respectively, all P<0.05). There was a negative correlation between complement C4, SF-36, and MMT-8 scores ( r=-0.424, -0.549, and -0.686, respectively, all P<0.05). Collectively, the findings from this study suggest that MRI T 2 mapping can objectively reflect the disease status of DM and PM.

Objective To analyze the risk factors for the occurrence of post transplantation diabetes mellitus (PTDM) in renal transplant recipients, establish a prediction model for PTDM and evaluate its prediction value. Methods Clinical data of 915 renal transplant recipients were retrospectively analyzed. According to the occurrence of PTDM, all recipients were divided into the PTDM group (n=78) and non-PTDM group (n=837). The main indexes of recipients were collected. The risk factors for the occurrence of PTDM in renal transplant recipients were analyzed by univariate and multivariate analysis. The prediction model for PTDM was established and its prediction value was evaluated. Results Family history of diabetes mellitus, body mass index (BMI), preoperative 2 h postprandial blood glucose and preoperative glycosylated hemoglobin were the independent risk factors for the occurrence of PTDM in renal transplant recipients. The prediction model for PTDM was logit (P)=2.199×family history of diabetes (yes=1, no=0)+0.109×BMI+0.151×2 h postprandial blood glucose (mmol/L)+0.508×glycosylated hemoglobin (%)-9.123. The results of receiver operating characteristic (ROC) curve showed that the area under the curve (AUC) of these 4 predictors combined for predicting PTDM in renal transplant recipients was 0.830 [95% confidence interval (CI) 0.786-0.873], the cut-off value was 0.0608, the sensitivity was 0.821, the specificity was 0.700, and the Youden index was 0.521 (P < 0.05). Conclusions Family history of diabetes mellitus, BMI, preoperative 2 h postprandial blood glucose and preoperative glycosylated hemoglobin are the independent risk factors for the occurrence of PTDM in renal transplant recipients. The prediction model for PTDM combined with4 predictors yield relatively high prediction value for PTDM.

Objective:To analyze the association of pre-transplant risk factors with diabetes mellitus after renal transplantation and examine the significance of preventing the occurrence in kidney transplantation recipients.Methods:A total of 290 kidney transplantation recipients were retrospectively reviewed at our transplantation center from August 2018 to May 2020.Diabetes mellitus after renal transplantation was employed as a primary outcome index.Multivariate Logistic regression model was utilized for constructing A (without adjusting for covariates)、B(covariates include: gender, dialysis mode, type of donation)and C(covariates include: gender, dialysis mode, type of donation, calcineurin inhibitor, antiproliferative drugs, primary disease, fasting blood glucose, 1 h postprandial blood glucose, fasting C peptide, 1 h and 2 h postprandial C peptide, fasting C-peptide index, 1 h postprandial C-peptide index, albumin, triglycerides, total cholesterol)to evaluate the relationship between diabetes mellitus after transplantation and age, body mass index, 2 h postprandial blood glucose(2 h-PG), HbA1c, and 2 h postprandial C-peptide index(2 h-CPI).Results:In model A, age [odds ratio(OR)1.1, 95% confidence interval( CI)1.0~1.1], BMI(OR 1.2, 95% CI 1.0~1.3), 2 h PG(OR 1.2, 95% CI 1.1~1.4), HbA1c(OR 2.7, 95% CI 1.5~4.9), 2 h-CPI(OR 0.7, 95% CI 0.5~1.0), model B/C had similar results with A. Age, BMI, 2 h PG and HbA1c were all risk factors for diabetes mellitus after transplantation while 2 h-CPI was a protective factor.Quartile stratification was analyzed by regression model.And trend test was significant( P<0.05). Conclusions:Age, BMI, 2 h PG, HbA1c and 2 h-CPI are correlated with diabetes mellitus after kidney transplantation.

Objective:To verify the reliability, accuracy and stability of the machine performance check (MPC) system of Varian′s TrueBeam series accelerator.Methods:After the installation was completed, the acceptance data were compared with the results of the first MPC operation to verify the reliability of the MPC results; the accuracy of the MPC results in the image-guided radiotherapy (IGRT) application was verified by the method of artificially introducing errors. The mechanical performance results of 60 groups of MPC from March 2019 to March 2020 were collected to calculate the mean value and standard deviation and compare the stability differences of each index.Results:The equipment error parameters obtained by MPC were all lower than those obtained by acceptance. The maximum difference between two sets of data was only 2mm and the threshold ratio was less than 20%. MPC had a high sensing accuracy for radiation and imaging position shift, and the r values were more than 90%. The vertical direction of the couch had a poor sense of displacement accuracy, and the r value was less than 73.7%. For this verification project, the angle of the treatment bed was the most stable, and the standard deviation did not exceed 0.01. The stability of other indexes did not significantly differ.Conclusions:MPC can be used as a verification tool for routine quality assurance of IGRT. The verification accuracy of radiation and imaging centers are better than the mechanical accuracy of gantry, collimator and couch.

Objective:To investigate a cluster epidemic of COVID-19 after a mass gathering activity in Ningbo of Zhejiang province and analyze the transmission chain and status of infection cases of different generations.Methods:The tracking of all the close contacts of the first COVID-19 case and epidemiological investigation were conducted on January 29, 2020 after a cluster epidemic of COVID-19 related with a Buddhism rally on January 19 (the 1.19 rally) in Ningbo occurred. The swabs of nose/throat of the cases and close contacts were collected and tested for nucleic acids by real-time fluorescence quantitative RT-PCR.Results:From January 26 to February 20, 2020, a total of 67 COVID-19 cases and 15 asymptomatic infection cases related with the 1.19 rally were reported in Ningbo. The initial case was the infection source who infected 29 second generation cases and 4 asymptomatic infection cases, in whom 23 second generation cases and 3 asymptomatic infection cases once took bus with the initial case, the attack rate was 33.82% (23/68) and the infection rate was 38.24% (26/68). The risks of suffering from COVID-19 and being infected were 28.91 times and 26.01 times higher in rally participants taking bus with initial case compared with those taking no bus with initial case. In this epidemic, 37 third+generation cases and 11 related asymptomatic infection cases occurred, the attack rate was 2.88% (37/1 283) and the infection rate was 4.76% (48/1 008). The main transmission routes included vehicle sharing and family transmission.Conclusion:It was a cluster epidemic of COVID-19 caused by a super spreader in a massive rally. The epidemic has been under effective control.

Objective:To describe the basic characteristics of clusters of coronavirus diseases 2019 (COVID-19) cases in Ningbo, Zhejiang province, and evaluate the generation time (Tg) and basic reproduction number ( R0) of COVID-19. Methods:The basic information and onset times of the clusters of COVID-19 cases in Ningbo were investigated, the inter-generational interval of the cases were fitted by using gamma distribution, and the R0 was calculated based on the SEIR model. Results:In the 15 clusters of COVID-19 cases, a total of 52 confirmed cases, 5 cases of nucleic acid-positive asymptomatic cases. The cases occurred from January 23 to February 4, the cases were mainly women. The incubation period was (6.11±3.38) days, and the median was 5 days. The Tg was (6.93±3.70) days. There were no significant differences in Tg between age group<60 years and age group 60 years and above, and between men and women ( P=0.551). According to the Tg calculated in this paper, the R0 of COVID-19 in Ningbo was 3.06 (95 %CI: 2.64- 3.51); according to the reported case transmission interval of 7.5 days in the literature, the R0 was 3.32 (95 %CI: 2.51-9.38). Conclusion:There is no age and gender specific differences in the Tg of clusters of COVID-19 cases in Ningbo, and COVID-19 has high infectivity and spreading power in early phase.

Objective: To investigate the incidence and risk factors contributing to post-transplant diabetes mellitus (PTDM) in kidney transplant recipients within one year post-transplantation. Methods: A total of 293 non-diabetic kidney transplant recipients were retrospectively analyzed. Patients were divided into non-PTDM group and PTDM group according to the diagnostic criteria of diabetes mellitus. The incidence of PTDM was calculated and the potential risk factors of PTDM were analyzed by univariate and multivariate Logistic regression analysis. Results: Among the 293 non-diabetic patients, 36 patients developed PTDM within 1 year, with an incidence of 12.3%. Multivariate Logistic analysis showed that age (OR 1.055, 95% CI 1.014-1.098, P=0.009) , body mass index [odd ratio (OR) 1.231, 95% confidence interval (CI) 1.084-1.398, P=0.001], polycystic kidney as the primary disease (OR 1.508, 95% CI 1.006-2.262, P=0.047) , 2-hour postprandial blood glucose (OR 1.186, 95% CI 1.04-1.53, P=0.011) , HbA1c (OR 1.732, 95% CI 1.075-3.428, P=0.015) and 1-hour postprandial blood C-peptide (OR 0.869, 95% CI 0.804-0.939, P=0.001) were independent risk factors for PTDM in kidney transplant recipients within 1-year post-transplantation. Conclusion Patients with older age, obesity, polycystic kidney as the primary disease, higher level of HbA1c and 2-hour postprandial blood glucose, and lower level of 1-hour postprandial blood C-peptide may have higher risk of developing PTDM.

Objective To investigate the distribution characteristics of pathogenic bacteria in infectious donors from organ donation after citizen's death and preventive strategies for renal transplant recipients. Methods Clinical data of 412 donors and 803 recipients from organ donation after citizen's death were retrospectively analyzed. All donors underwent culture of airway secretions, urine, blood and renal lavage fluid. The incidence rate of infection, distribution and composition ratio of pathogenic bacteria of donors from organ donation after citizen's death were observed. The scores of all donors were evaluated according to the length of intensive care unit (ICU) stay for donors, the situation of abdominal trauma and the results of body fluid culture, etc. According to the score, the recipients received different infection prevention regimes. The incidence rate of donor-derived infection (DDI) and clinical prognosis of the recipients were analyzed. Results A total of 243 donors were diagnosed with infection in 412 donors from organ donation after citizen's death with an infection rate of 59.0%. In total, 456 strains of pathogenic bacteria were isolated, mainly derived from the airway secretions (71.7%). Gram-negative bacteria dominantly consisted of Klebsiella pneumoniae and acinetobacter baumannii. Gram-positive bacteria mainly included staphylococcus aureus and fungus mainly included yeast-type fungus. Three recipients (kidneys from 2 donors respectively) developed DDI with an incidence rate of 0.4%. Conclusions The infection rate of donors from organ donation after citizen's death is relatively high. It is effective to prevent the incidence of DDI by grading the risk of infection of donors and adopting rational preventive plan according to the score.

Objective To investigate the safety of young recipients undergoing living donor renal transplantation from elderly relative donors through long-term follow-up of the pathological changes. Methods According to the age of donors, 28 young recipients were divided into the observation group (n=14, elderly donors) and control group (n=14, young and middle-aged donors). The 7-year survival after renal transplantation, the serum creatinine (Scr) levels at various postoperative time points were compared between two groups. The chronic pathological injury scores of renal allograft biopsy at time-zero, postoperative 6-month and 7-year were compared between two groups. The expression levels of renal interstitial fibrosis indicators connective tissue growth factor (CTGF), transforming growth factor (TGF)-β, laminin (LN), fibronectin (FN), cell senescence indicators intercellular connexin (Cx)-43 and mammalian target of rapamycin (mTOR) at postoperative 6-month and 7-year were compared between two groups. Results The 7-year survival rates in the observation and control groups were 78.5% and 92.8% with no statistical significance (P > 0.05). In the observation and control groups, the levels of Scr were 190 and 160 μmol/L at the postoperative 7 d, and 170 and 125 μmol/L at postoperative 1 month. At each postoperative time point, the levels of Scr in the observation group were significantly higher than those in the control group (all P > 0.05). The total chronic pathological injury scores of renal transplant biopsy at time-zero in the observation group was significantly higher than that in the control group (P > 0.05), whereas the total chronic pathological injury scores at postoperative 7-year did not significantly differ between two groups (P > 0.05). Within either group, the total chronic pathological injury scores at postoperative 7-year was remarkably higher than those at time-zero and postoperative 6-month (both P < 0.05). The expression levels of CTGF, TGF-β, LN, FN, mTOR, Cx43 of renal transplant tissue at postoperative 7-year did not significantly differ between two groups (all P > 0.05). Conclusions The long-term follow-up outcomes demonstrate that the pathological changes of young recipients undergoing renal transplantation from elderly donors are similar to those from young and middle-aged donors. It is safe and feasible for young recipients to undergo renal transplantation from elderly donors in the pathological perspective.

Objective To evaluate the effect of dexmedetomidine on postoperative outcomes in pa-tients undergoing off-pump coronary artery bypass grafting ( OPCABG) . Methods One hundred and twen-ty-two patients of both sexes, aged 40-75 yr, with body mass index of 18. 5-32. 0 kg∕m2 , of American So-ciety of Anesthesiologists physical status Ⅲ or Ⅳ, with New York Heart Association Ⅱ or Ⅲ, with lelf ventricular ejection fraction>40％, scheduled for elective OPCABG, were divided into 2 groups ( n=61 each) using a random number table method: dexmedetomidine group ( group D) and control group ( group C) . Dexmedetomidine was intravenously infused in a loading dose of 0. 6μg∕kg at 15 min before anesthesia induction, followed by a continuous infusion of 0. 4 μg · kg-1 · h-1 until the end of surgical procedure in group D. The equal volume of normal saline was given instead in group C. The emergence time, extubation time, length of intensive care unit stay and postoperative length of hospital stay were also recorded. Results Compared with group C, the extubation time, length of intensive care unit stay, and postoperative length of hospital stay were significantly shortened, and the emergence time was prolonged in group D ( P<0. 05) . Conclusion Dexmedetomidine can promote postoperative outcomes in the patients undergoing OPCABG.