BACKGROUND:Fluorosis is a disorder of enamel development caused by long-term intake of large amounts of fluoride during enamel development. OBJECTIVE:To further explore the molecular mechanism of dental fluorosis formation by screening the differentially expressed genes associated with calcium homeostasis in ameloblasts by transcriptome sequencing technology. METHODS:LS8 cells were treated with 0,0.4,0.8,1.6,3.2 and 6.4 mmol/L sodium fluoride(NaF)for 24,48 and 72 hours to observe the effects of different concentrations of NaF on the morphology,cell activity and intracellular Ca2+ concentration of LS8 cells.The differentially expressed genes were screened by transcriptome sequencing and validated. RESULTS AND CONCLUSION:After 24 hours of treatment,the cells treated with 0,0.4,and 0.8 mmol/L NaF were in good growth condition,with increased cell number and clear cell outline.When the NaF concentration was≥1.6 mmol/L,the cells were gradually shrunken and became smaller and the number of cells decreased with the increase of NaF concentration.After 48 and 72 hours of treatment,the number of cells increased in the 0,0.4 mmol/L NaF groups,while gradually decreased in the 0.8,1.6,3.2 mmol/L NaF groups,with rounded and smaller cell morphology.The cells in the 6.4 mmol/L NaF group were shrunken,rounded and suspended in the medium,with almost no adherent cells.When treated with the same concentration of NaF,LS8 cells were in optimal growth after 24 hours of treatment.Results from cell counting kit-8 assay showed that when treated with the same concentration of NaF,the cell activity decreased with the increase of treatment time;when the treatment time was the same,the cell activity decreased with the increase of NaF concentration.After 24 hours of treatment,the intracellular Ca2+ concentration increased with the increase of NaF concentration.Transcriptome sequencing analysis identified genes involved in the regulation of cellular calcium homeostasis:Hsp90b1,Canx,Calr,and Hspa5 that were significantly upregulated(P＜0.05)and Cacna1a that was significantly downregulated(P＜0.05).To conclude,the inhibitory effect of NaF on LS8 cell proliferation may be related to the abnormal increase in intracellular Ca2+ concentration,and the mechanism may be caused by the upregulation of the expression of protein processing and synthesis pathways Hsp90b1,Canx,Calr,and Hspa5 and the downregulation of the expression of calcium signaling pathway Cacna1a.

Objective:To identify the etiology and genetics of the human parainfluenza virus type 3 (HPIV3) virus which caused an acute respiratory tract infection outbreak in a primary school in Shenyang.Methods:Throat swab samples were collected from 17 students of the primary school where the epidemic of acute respiratory infection outbreak in December 2020 in Shenyang, Liaoning province. TaqMan low-density arrays (TLDA) real-time PCR was performed to simultaneously detect multiple respiratory pathogens. The HN gene was amplified using nested RT-PCR and sequenced, followed by phylogenetic analysis for those HPIV3 positive samples.Results:Of the 17 specimens, 10 were HPIV3 positive by TLDA Real-time PCR, and were accompanied by conditional pathogen infection, consequently, amplification result ed in 7 complete HN sequences. Phylogenetic analysis showed that the infected HPIV3 virus of the outbreak belonged to HPIV subtype C3a. All the 7 strains detected in this study belonged to subbranch C3a.1 evolutionary branch, with a nucleotide homology of 99.9%, a nucleotide homology of 94.56 with the prototype strain Wash/47885/57 and 99.5% with the most phylogenetically close strain of ZJ/11-s-165/KP690785/CHN/11.Conclusions:The HPIV3 virus caused the acute respiratory tract infection outbreak in Shenyang in 2020 and HPIV subtype C3a1 was detected firstly in Northeast China.

Objective:To systematically review the effect of preoperative pulmonary rehabilitation on postoperative pulmonary complications in patients with lung cancer.Methods:The randomized controlled trials of preoperative pulmonary rehabilitation for lung cancer published in the past 10 years were retrieved in China Biomedical Literature Database, China National Knowledge Infrastructure, VIP, WanFang Data, PubMed, Embase, Web of Science, Cochrane Library and Wiley Online Library. The search limit was from January 1, 2010 to January 1, 2021. The quality evaluation and data extraction of the included article were carried out, and the Meta-analysis of the outcome indicators of postoperative pulmonary complications was conducted.Results:A total of 12 articles were included. Meta-analysis showed that the incidence of postoperative pulmonary complications in the intervention group was lower than that in the control group, and the difference was statistically significant [ RR=0.42, 95% CI (0.32, 0.55) , P<0.01]. Subgroup analysis was performed according to the duration of intervention, and the results showed that when the intervention duration was one week, the difference between the intervention group and the control group was statistically significant [ RR=0.36, 95% CI (0.24, 0.55) , P<0.01], when the intervention duration was more than one week, the difference between the intervention group and the control group was statistically significant [ RR=0.48, 95% CI (0.33, 0.68) , P<0.01) ]. Subgroup analysis was conducted with different evaluation time after operation, and the results showed that when the evaluation time was one month, the difference between the intervention group and the control group was statistically significant [ RR=0.48, 95% CI (0.34, 0.68) , P<0.01], when the evaluation time was more than one month, there was no significant difference between the intervention group and the control group [ RR=0.39, 95% CI (0.08, 1.85) , P=0.24]. Except for pneumonia or pulmonary infection, atelectasis, and bronchopleural fistula, there was no significant difference in the incidence of postoperative pulmonary complications in patients with lung cancer ( P>0.05) . Conclusions:Exercise that includes breathing training for at least one week is a common intervention for preoperative pulmonary rehabilitation. Preoperative pulmonary rehabilitation is beneficial to reduce the overall and one month postoperative pulmonary complications after lung cancer surgery, but the impact on postoperative pulmonary complications evaluated for more than one month and specific complications requires further study.

Objective:To investigate the clinical value of radiomics based on computed tomography (CT) examination in preoperative differential diagnosis of pancreatic serous cystadenoma (SCA) and mucinous cystadenoma (MCA).Methods:The retrospective case-control study was conducted. The clinicopathological and imaging data of 154 patients with pancreatic cystic neoplasms who were admitted to the First Affiliated Hospital, Zhejiang University School of Medicine from January 2012 to December 2019 were collected. There were 24 males and 130 females, aged (50±13)years. Of the 154 patients, 99 cases were diagnosed as SCA and 55 cases were diagnosed as MCA. All the 154 patients underwent plain and enhanced CT scan of pancreas before operation. The clinical characteristics, radiology features and radiomics features of all patients were collected to construct the clinical characteristics model, radiology model, radiomics model and fused model. The receiver operating characteristic (ROC) curve of each model was drawn, and those constructed models were evaluated by area under the curve (AUC), accuracy, sensitivity, specificity, positive predictive value and negative predictive value. Based on the optimal model, the nomogram was constructed. Observation indicators: (1) establishment and validation of clinical characteristics model; (2) establishment and validation of radiology model; (3) establishment and validation of radiomics model; (4) establishment and validation of fused model; (5) nomogram of fused model. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the Mann-Whitney U test. Count data were described as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test or Fisher exact probability. Results:(1) Establishment and validation of clinical characteristics model: 3 clinical characteristics, including age, symptoms and preoperative serum CA19-9, were selected using multinomial logistic linear regression analysis to construct the clinical characteristics model. Result of the multinomial logistic linear regression analysis was expressed by formula ①: clinical characteristics model score=0.635-0.007×age+0.054×clinical symptoms+0.108×preoperative serum CA19-9. The ROC curve for the test dataset of clinical characteristics model was drawn. The AUC, accuracy, sensitivity, specificity, positive predictive value and negative predictive value of clinical characteristics model were 0.611(95% confidence interval as 0.488?0.734, P<0.05), 56.6%, 66.7%, 56.3%, 41.5%, 78.4% for the training dataset and 0.771(95% confidence interval as 0.624?0.919, P<0.05), 77.8%, 63.1%, 88.5%, 80.1%, 76.7% for the test dataset, respectively. (2) Establishment and validation of radiology model: 5 radiology characteristics, including tumor location, the number of tumors, tumor diameter of cross section, lobulated tumor and polycystic tumor (more than 6), were selected using multinomial logistic linear regression analysis to construct the radiology model. Result of the multinomial logistic linear regression analysis was expressed by formula ②: radiology model score=?0.034+0.300×tumor location+0.202×the number of tumors+0.014×tumor diameter of cross section?0.251×lobulated tumor?0.170×polycystic tumor (more than 6). The ROC curve for the test dataset of radiology model was drawn. The AUC, accuracy, sensitivity, specificity, positive predictive value and negative predictive value of radiology model were 0.862(95% confidence interval as 0.791?0.932, P<0.05), 78.8%, 81.8%, 77.5%, 62.8%, 90.2% for the training dataset and 0.853(95% confidence interval as 0.713?0.994), P<0.05), 88.9%, 89.4%, 88.5%, 85.0%, 92.0% for the test dataset, respectively. (3) Establishment and validation of radiomics model: 4 categories of a total 1 067 radiomics features were extracted from 154 patients with pancreatic cystic neoplasms, including 7 first-order histogram features, 53 texture features, 848 wavelet features and 159 local binary pattern features. A total of 896 stable radiomics features were retained to construct the model, based on the condition of intraclass correlation coefficient >0.9. After selected by variance threshold and correlation coefficient threshold, 350 radiomics features were retained. Fifty synthetic radiomics features were constructed based on the original features in order to obtain potential radiomics features, and the total number of radiomics features was 400. After analyzed by the five-fold recursive feature elimination, 22 radiomics features were screened out, including 13 wavelet features, 7 synthetic radiomics features and 2 local binary pattern features. The support vector machine algorithm was used to construct the radiomics model. The penalty coefficient 'C' and parameter 'γ' of the radiomics model were 35.938 and 0.077, respectively. The kernel function of the radiomics model was 'radial basis function kernel'. The ROC curve of radiomics model using 5-fold cross validation was drawn. The average AUC, accuracy, sensitivity, specificity, positive predictive value and negative predictive value of the radiomics model were 0.870 ( P<0.05), 83.1%, 81.8%, 83.8%, 73.8% and 89.2%, respectively. (4) Establishment and validation of fused model: the fused model was constructed after selecting the tumor location and lobulated tumor of radiology characteristics and radiomics score. Result of the multinomial logistic linear regression analysis was expressed by formula ③: fused model socre=?0.154+0.218×tumor location?0.223×lobulated tumor+0.621×radiomics score. The ROC curve for the test dataset of fused model was drawn. The AUC, accuracy, sensitivity, specificity, positive predictive value and negative predictive value of fused model were 0.893(95% confidence interval as 0.828?0.958, P<0.05), 83.7%, 81.8%, 84.5%, 71.1%, 90.9% for the training dataset and 0.966(95% confidence interval as 0.921?0.999, P<0.05), 91.1%, 84.2%, 96.2%, 94.1%, 89.3% for the test dataset, respectively. (5) Nomogram of fused model: the nomogram of fused model was illustrated with the Youden index of 0.416. Conclusion:The prediction model based on the radiomics signature and radiological features extracted from preoperative CT examination can make the differential diagnosis of pancreatic SCA from MCA.

Based on the current situation and task of fighting COVID-19, and combined with emergency management mode of public health emergencies and participation of multi-times emergency rescue practices along with the case analysis and literature review and brain-storming, we constructed a basic framework of the emergency command system of public health emergencies in COVID-19 epidemic prevention and control background. The framework contained four modules: the response mechanism, the organizational structure, the emergency capacity, and the supervisory mechanism and the advantages and key points in implementing this emergency command system was discussed.

【Objective】 To investigate and summarize the clinical and imaging features of a few patients with coronavirus disease 2019 (COVID-19) in Lanzhou City. 【Methods】 We carried out a retrospective analysis of the epidemiological data, laboratory results and clinical imaging features of eight hospitalized patients with confirmed COVID-19 in The First Hospital of Lanzhou University from January 23 to February 23, 2020. 【Results】 The sex ratio (men to women) of the 8 patients was 5∶3 while their age ranged from 24 to 57 years old. The incubation period was 1-10 days. Of the 8 patients, 7(87.5%) had COVID-19 brought in from other places in China and 1(12.5%) was a secondary infection case. The main clinical manifestations included cough in 6 cases (75%), fever in 4 cases (50%), expectoration in 3 cases (37.5%), and fatigue in 2 cases (25%). All the 8 cases indicated abnormal manifestations in blood routine examinations, 4 cases (50%) decreased in WBC, 7 cases (87.5%) decreased in Lym count, 5 cases (62.5%) increased in LDH, 1 case (12.5%) increased in CK, 1 case(12.5%) increased in CK-MB, 4 cases (50%) increased in CRP, 2 cases (25%) increased in PCT, and 1 case (12.5%) increased in D-dimer. Of the 2 patients examined by chest digital radiography (DR), one DR finding was not typical and the other one suggested increased bilateral lung markings. Six patients were examined by HRCT, of whom four (50%) showed multiple ground glass opacities on both lobes and two (25%) showed multiple ground glass opacities only on the right lobe; none of the 6 imaging findings suggested pleural effusion. Six patients were discharged from hospital after being cured and 1 patient still underwent treatment. 【Conclusion】 Most of these 8 patients had COVID-19 imported from outside the city, and the patients were relatively young with few underlying diseases. Their major symptoms were fever, cough, and expectoration. All of them exhibited abnormal findings in blood routine examinations; half of them suggested increased CRP while a few ones showed abnormal CK and Ddimer values. The imaging manifestations of most patients were multiple ground glass opacities near the peripheral pleura.

Objective: To explore the value of CT texture analysis (CTTA) in differentiating the pathological grade of urothelial carcinoma of the bladder (UCB). Methods: A total of 53 lesions from 43 patients with bladder cancer confirmed by postoperative pathology were retrospectively analyzed, including 27 cases of high-grade urothelial carcinoma (HGUC) and 26 cases of low-grade urothelial carcinoma (LGUC). All the patients took pelvic CT and enhanced scanning in the same CT scanner with same scanning parameters. Lesions on both plain and enhanced CT images were delineated on software by two radiologists to extract the corresponding volumes of interest (VOI) and then 92 parameters based on feature classes were generated. The average values of two radiologists were obtained. The difference parameters between HGUC group and LGUC group were screened by nonparametric test, and the receiver operating characteristic (ROC) was drawn. The corresponding optimal thresholds were determined and diagnostic effect was assessed. Results: Nine difference texture parameters between HGUC group and LGUC group were selected, including 5 parameters on unenhanced images, namely, skewness, root mean squared, cluster shade, zone percentage and large area high gray level emphasis. There were 4 parameters on enhanced images, namely, skewness, kurtosis, cluster shade and zone percentage. The largest area under curve of 0.840±0.058 (95% CI 0.726-0.955) was obtained from skewness generated by VOI of unenhanced images. The cut-off value of skewness was 0.186 5, which permitted the diagnosis of HGUC with sensitivity of 92.59%, specificity of 73.08%, positive predictive value of 78.13%, negative predictive value of 90.48% and accuracy of 83.02%. Conclusion CTTA can effectively distinguish between LGUC and HGUC. Skewness from unenhanced CT images had the optimal diagnostic performance.

Objective SD rats were immuned with the transgenic tomatoes which carried fused gene of a region of PAc Strep-tococcus mutants and cholera toxin B subunit.The immunogenicity was tested to explore secure and economic edible vaccines a-gainst dental caries.Methods A total of 18 eighteen-day-old female SD rats were subdivided randomly into three groups:the exper-imental group which were fed with transgenic tomato juice containing chimaera protein PAcP/CTB;the positive control group which were treated with deactivated S.mutans;the negative control group which were not treated with transgenic tomato juice.Rats were immuned once per week for four weeks.Blood and saliva were collected at one day before the first immunity and one week after each immunization.IgG of blood serum and SIgA of saliva were detected using the enzyme-linked immunosorbent assay (indirect ELISA) testing.On day 70,rats were terminated.The maxillary and mandibular bones were subsequently taken out to count dental caries′scores.Results Post immunization,the experimental group and the positive control group had statistical significant levels of speci-ficity IgG in serum and SIgA in saliva compared to the negative control group (P <0.05).There was a significance difference be-tween the experimental group and the negative control group except in Dx levels of caries loss (P <0.05).Conclusion The targeted protein expressed on the transgenic tomatoes is immunogenic,which can effectively induce mucous membrane immune response and the systematical immunoreaction to suppress the occurrence of the dental caries.

ObjectiveTo investigate the morphologic features of coronary sinus (CS)-left atrium muscle connections,and evaluate the function and anatomical features of coronary sinus on dual-source CT coronary angiography (DSCTCA).MethodsImages of DSCTCA of 144 patients [ control group consisted of 96 patients,and atrial fibrillation (AF) group consisted of 48 patients] were reviewed.The existence of coronary sinus-right atrium muscle connections was indirectly evaluated by measuring the cross-sectional area changes of the CS during atrial systole and atrial diastolic.The number,location,length of the CS-left atrium muscle connections andthe relationship between CS-left atrium muscle connections and CS morphological characteristics were studied.The t test for continuous variables and Chi-square test for categorical variables were used in statistical analysis.Results( 1 )The anatomic course of the CS in relation to the mitral ring was straight,mild curvature and high riding of 62,16 and 18 cases in control group and 10,8 and 30 cases in AF group,respectively.There was not statistical significance between the 2 group (x2 =0.093,P=0.954). (2)The CS length was (34.1 ±9.1),(33.8 ±8.9)mm in Control group and AF group,respectively.There was no statistical significance between the 2 group ( t =- 0.486,P =0.628 ).(3) Coronary sinus-left atrium muscle connections were seen in 131 of the 144 patients (91.0％).A single connection was seen in 103 of the 144 patients,with a mean length of (22.6 ± 12.7)mm within (6.3 ± 5.8 ) mm of the coronary sinus ostium.28 patients had two connections; distal connections measured ( 13.2 ± 6.2)mm in length within (16.7 ± 6.8 ) mm of the coronary sinus ostium,and proximal connections measured ( 11.1 ± 3.6 ) mm in length within (2.1 ± 1.9) mm of the coronary sinus ostium.And there was no statistical difference the number and length of CS-left atrium connections in between Control group and AF group (P ＞ 0.05 ).(4)The CS narrowed 22.4％ (44.5/198.8 )in cross-sectional area from atrial diastolic to atrial systole in control group( t =- 21.076,P ＜ 0.01 ),while the CS had no obvious contraction in AF group(t =0.374,P ＞ 0.05).The cross-sectional area of the coronary sinus during diastole was obviously larger in the AF group than in the control group[( 230.4 ±77.0) mm2 vs (198.8 ±65.4) mm2,respectively,t =- 2.579,P =0.01 ].In control group ( n =9 ),the coronary sinus-left atrium connection was not seen,however,all showed a CS constriction during atrial systole,indicating that coronary sinus-left atrium muscle continuity is not likely the primary cause for coronary sinus contractions. Conclusions DSCTCA can clearly show the anatomical characteristics of CS,it can help to understand the length,number and location of the CS-left atrium muscle connection.

Objective To evaluate abdominal CT scan in predicting complications and mortality of acute pancreatitis patients. Methods CT imaging data of 606 AP patients from June 2010 to October 2011 were analyzed retrospectively. Fatty liver, pleural effusion, suprahepatic space effusion, biliary tract disease,gastric bare area involvement (GBAI),adrenal gland involvement (AGI) and perirenal space involvement (PSI) were evaluated,and the relationship between CT findings and complications and mortality was analyzed. Results (1) The Logistic regression analysis showed six risk factors for complications of AP,including obesity,fatty liver,PSI,AGI,GBAI and suprahepatic space effusion.The sensitivity,specificity and accuracy of Logistic regression model for predicting complications were 81.3％,89.1％ and 85.3 ％,respectively. (2) The Logistic regression analysis showed four risk factors for mortality of AP,including obesity,AGI,GBA and suprahepatic space effusion.The sensitivity,specificity and accuracy of Logistic regression model for predicting mortality were 33.3％, 98.6％, 96.0％, respectively.Conclusions Abdominal CT scan effectively indicates the signs of tissue and organ involvement in AP.These CT findings relate with the prognosis of AP.