BACKGROUND:Root canal preparation is a key step in root canal therapy.In recent years,with the rapid development of new nickel-titanium instruments,the results of root canal shaping ability have been significantly improved.However,the shaping abilities of different nickel-titanium instruments are also different.At present,there are few reports about the influence of the shaping ability of R-phase heat treatment NIC X-FILE and DENCO Pre-Shaper in simulated curved canals. OBJECTIVE:To compare the shaping effect of NIC X-FILE and DENCO Pre-Shaper nickel-titanium instruments in preparation for simulated curved canals. METHODS:Fifty simulated resin-curved canals were selected and randomly divided into two groups(n=25).NIC X-FILE and DENCO Pre-Shaper nickel-titanium files were used for root canal preparation.The root canal preparation time was recorded.Images of pre-and post-root canal preparation were taken.Image processing and analysis software were used to measure the amount of resin removed from the inner and outer walls of the root canal at each observation point.Statistical software was used to compare the root canal preparation time and centering ability of two kinds of mechanical nickel-titanium files. RESULTS AND CONCLUSION:(1)The average root canal preparation time was(1.58±0.02)minutes in the DENCO Pre-Shaper group and(2.22±0.03)minutes in the NIC X-FILE group.There was a significant difference between the two groups(P<0.05).(2)The amount of resin removed from the inner walls of the root canal of the DENCO Pre-Shaper group at 4,5,7,8,9,and 10 mm from the apical foramen was higher than that of the NIC X-FILE group(P<0.05).The amount of resin removed from the outer walls of the root canal of the DENCO Pre-Shaper group at 3,5,6,7,and 8 mm from the apical foramen was lower than that of the NIC X-FILE group(P<0.05).(3)At 2,4,5,6,7,8,and 9 mm away from apical foramen,the centering ability of the NIC X-FILE group was better than that of the DENCO Pre-Shaper group(P<0.05),and the centering ability of the NIC X-FILE group was the best at 4 mm away from apical foramen.(4)The results show that DENCO Pre-Shaper has higher mechanical efficiency than NIC X-FILE nickel-titanium root canal files.However,the centering ability of DENCO Pre-Shaper is inferior to NIC X-FILE nickel-titanium root canal files.

ObjectiveTo analyze the epidemiological characteristics and etiology of clustered outbreaks of hand， foot， and mouth disease （HFMD） in Pudong New Area， Shanghai from 2017 to 2022， and to provide a scientific basis for the prevention and control of HFMD in the area. MethodsThe data related to HFMD clustered outbreaks from 2017 to 2022 were obtained from the Pudong New Area HFMD outbreak database. Descriptive analysis was conducted to explore the outbreak scope， seasonal characteristics， distribution of occurrence settings， and etiological composition. ResultsFrom 2017 to 2022， Pudong New Area reported a total of 2 547 HFMD clusters， involving 8 884 cases， with an average of 3.49 cases per event. The majority of events （78.52%） had between 2 and 4 cases. The peak reporting periods for clustered HFMD from 2017 to 2019 and in 2021 were during the summer （May‒July） and autumn （September‒November）. The seasonal pattern was less distinct in 2020 and 2022， likely due to the impact of the COVID-19 pandemic. The majority of clustered outbreaks occurred in childcare facilities （44.64%）， followed by households/neighborhood committees （44.21%）， with schools accounting for a smaller proportion （12.39%）. The etiology revealed the coexistence of multiple enterovirus genotypes， with a positive detection rate of 60.46%， and CoxA6 being the dominant strain. ConclusionHFMD clustered outbreaks in Pudong New Area show fluctuating trends， with significant yearly differences in the number of incidents. The predominant seasons for outbreaks are summer and autumn， with CoxA6 identified as the dominant strain. The implementation of prevention and control measures for COVID-19 significantly reduced the occurrence of HFMD outbreaks. Continuous monitoring and focus on large-scale clustered outbreaks in key institutions are essential for the future.

ObjectiveTo determine the influence of Buzhong Yiqitang on miRNA expression in thyroid tissues of mice with autoimmune thyroiditis （AIT）. MethodThirty female 8-week-old NOD.H-2^h4 mice were randomly assigned into normal control group， model group， and Buzhong Yiqitang group （BG）， 10 in each group. Mice were subjected to a diet containing 0.05% sodium iodide for 8 weeks to build the AIT mouse model. After 8 weeks of administration （ig）， samples were collected. A thyroid biopsy was performed on each group of mice， and differential miRNAs in thyroid tissues from each group of mice were analyzed based on experimental validation and bioinformatics. ResultCompared with the conditions of normal control group， thyroid lymphocytes had significant inflammatory infiltration， and there was an increase in serum TgAb level and interleukin（IL）-6 and IL-17 expression and a decrease in IL-1β expression in mice of the model group （P<0.05， P<0.01）. In addition， 154 differentially expressed miRNAs were found. Compared with the conditions of model group， the degree of thyroid tissue inflammation was alleviated， and serum TgAb level， and IL-1β， IL-6 and IL-17 expression of mice treated with the Buzhong Yiqitang were reduced （P<0.05， P<0.01）. Additionally， 112 differentially expressed miRNAs were identified in the BG group. Validation using real-time polymerase chain reaction（Real-time PCR） showed the same trend for miR-326-3p， miR-128-3p， miR-223-5p， miR-141-3p， miR-871-3p， and miR-204-3p as that obtained from miRNA sequencing. In particular， gene ontology（GO） functions were enriched for regulation of T cell activation， oxidative stress， and miRNA binding. Pathways identified by Kyoto encyclopedia of genes and genomes（KEGG）database tended to be enriched in phosphatidylinositol 3-kinases（PI3K）/protein kinase B（Akt）， mitogen-activated protein kinase（MAPK）， and cyclic adenosine monophosphate（cAMP） signaling pathways. Based on miRNA prediction differences， three key genes were identified： SMAD3， JAK2， and STAT3. ConclusionBushong Yiqitang might treat autoimmune thyroiditis by regulating 6 miRNAs.

Objective To understand the spatial epidemic characteristics of hand-foot-mouth disease in Pudong New Area of Shanghai from 2015 to 2018, and to provide reference for prevention and control. Methods SPSS 21.0 software was used for statistical analysis of the reported incidence of hand-foot-mouth disease, ArcGIS 10.2 software was used to make geographic distribution map, and OpenGeoDa software was used to make spatial autocorrelation analysis. Results The global Moran's I autocorrelation coefficient of the reported incidence rate of hand-foot-mouth disease in various streets and towns in Pudong New Area of Shanghai was 0.38, which was statistically significant (P=0.001). Local spatial autocorrelation analysis found that 5 streets were in high-high area. Conclusion The geographical distribution of reported incidence of hand-foot-mouth disease in various streets and towns of Pudong New Area in Shanghai was spatially aggregated, and the reported incidence decreased from north to south.

Objective To study the clinical value of electronic bronchoscope in diagnosis and treatment of recurrent dyspnea in neonates.Method From October 2014 to October 2017,the clinical data of recurrent dyspnea receiving electronic bronchoscopy examination and treatment in the neonatal intensive care unit of our hospital were retrospectively selected.Their clinical characteristics and treatment effects were summarized and analyzed.Result A total of 171 infants of neonatal recurrent respiratory infections were examined using electronic bronchoscope.The top four causes included endo－tracheo－bronchitis in 78 cases (45.6%), laryngomalacia, and tracheobronchomalacia in 22 cases (12.9%), airway stenosis in 14 cases (8.2%) and esophagotracheal fistula in 12 cases ( 7.0%).The complications of intraoperative and postoperative included decline of percutaneous oxygen saturation and /or heart rate (20.5%, 35/171), mucosal bleeding (12.3%, 21/171 ), and fever after bronchoalveolar lavage.Electronic bronchoscopy examination confirmed all the 171 neonates′diagnosis and some of them recovered after corresponding treatment.78 cases of infants with endo－tracheobronchitis were all cured.22 cases of laryngomalacia and tracheobronchomalacia and nine patients with airway stenosis improved and were discharged after treatment . One patient with subglottic stenosis received bronchoscopic holmium laser ablation therapy and the airway significantly expanded.No re－stenosis was found during follow－up.Conclusion Electronic bronchoscopy is an important method to determine the cause of recurrent dyspnea in newborns , and it′safe,reliable and can play a therapeutic role in some neonates.

Objective To investigate the preventive effects of lamivudine combined with chemotherapy drugs on hepatitis B virus reactivation in patients with HBV infection and tumor. Methods From July 2014 to February 2017,a total of one hundred and twenty patients with HBV infection and tumor in Nanchong Central Hospital were selected and were divided into the observation group and control group with 60 cases in each group. The control group received conventional chemotherapy and liver protection treatment,the observation group was given lamivudine prophylaxis treatment(100 mg/d,1 time/d) based on the treatment in the control group, two groups were treated for 8 weeks. Results The rates of hepatitis B virus reactivation in the observation group and the control group were 5. 0％(3/60) and 33. 3％(20/60),respectively,and the difference between the two groups was statistically significant (χ2=15. 692,P<0. 05) . There was no significant difference in serum glutamic acid transferase and aspartic transferase in the patients before and after treatment ( P>0. 05 ) , and the control group showed an upward trend ( P<0. 05) . After treatment,the serum ALT and AST in the observation group ((31. 98±6. 33)U/L,(26. 38±4. 98)U/L) were lower than those in the control group((43. 89±6. 73)U/L, (51. 78±5. 99)U/L)(t=8. 294,11. 842,P<0. 05). After treatment,the HBV DNA in the observation group and the control group((0. 16±0. 04) ×103copies/ml,(5. 02±1. 72) ×103copies/ml) were lower than those before treatment ((14. 55±2. 14)×103copies/ml,(14. 09±1. 98 copies/ml )(t=25. 498,8. 142,P<0. 05),and the HBV DNA in the observation group after treatment was also lower than that of the control group. The difference between the two groups was statistically significant ( t=24. 292,P<0. 05) . Conclusion Lamivudine combined with chemotherapy drugs used in patients with HBV infection and tumor can prevent hepatitis B virus reactivation,it does not affect the patient′s liver function,it can inhibit the replication of hepatitis B virus,so it has good application values.

Objective:To observe the clinical effect of TOMY self-ligation appliance technique in the treatment of anterior crossbite and moderate crowding, and to explore its clinical application.Methods:A patient, manifested as anterior crossbite and moderate dentition crowing, diagnosed as Angle class Ⅲ subclass malocclusion, MaoⅡ1+Ⅰ1 malocclusion, high angle,and facial asymmetry, was selected.This patient was treated with TOMY self-ligation appliance technique without tooth extraction.The length and width of the dental arch, the width of the alveolar bone and the width of the basal arch were measured before and after treatment;the lateral radiographs of the patient were taken too.Results:After treatment,the upper and lower dentition arranged in neat rows, reached a neutral occlusal relationship;SNA, SNB and ANB had no obvious changes;the lip inclination of anterior teeth was increased by 10 degrees, and reached the normal value;the upper and lower dental arch width, alveolar bone width, basal bone arch width and dental arch length were lower than before treatment.Conclusion:For the patient with anterior crossbite and moderate dental crowding treated with non-extraction, the TOMY self-ligation technique can be considered to use, by increasing the arch width and length to improve the anterior crossbite and moderate crowding, in order to achieve the effective treatment.

Objective:To investigate the site and characteristic ofp53 gene mutations in familial or early-onset breast cancer patients in part population of southern China.Methods:A total of 150 patients with familial and early-onset breast cancer in parts population of southern China were enrolled.Genomic DNA was isolated from each peripheral blood sample,and the entire coding sequence and exon and intron splicing region of p53 gene were amplificated by PCR in the 150 patients.The mutation analysis were detected by denaturing high performance liquid chromatography (DHPLC) and confirmed by DNA sequence analysis.Results:In the 150 patients with familial and early-onset breast cancer,6 mutations including one novel pathogenic mutation 869_888 ins20 (insert mutation) and 5 previously reported pathogenic mutations (deletion mutation 643_660de118 and 4 missense mutation 91G＞A,215C＞G,537T＞G,743G＞A) were identified in p53 gene encoding region in 9 patients of breast cancer.Moreover,one same sense mutation 141G＞A in exon 4,one 16 bases deletion in intron 3,and 9 single nucleotide polymorphisms in p53 gene introns were also identified.The total mutation frequency ofp53 gene in 150 patients with familial breast cancer and early-onset breast cancer from part population of southern China was 6.00％,and the mutation frequency of familial breast cancer and early-onset breast cancer was 6.81％ and 6.25％,respectively.Conclusion:The total mutation frequency ofp53 gene in 150 patients with familial breast cancer and early-onset breast cancer from partpopulation of southern China is higher than the frequency previously reported.The pathogenicity of the novel mutations (insert mutation) 869_888ins20 will be confirmed by function analysis in the future study.The deletion mutation 643_660de118 enriches the p53 gene mutation database among Chinese population,which is probably the specific mutation of breast cancer in Chinese population.

Objective To analyze the GDM of 336 cases with chronic HBV in pregnancy. Methods According to HBV DNA≥1.0 × 103 IU/mL, participants were divided into HBV DNA (+) or (-) group. 409 cases without HBV were selected as control group. Differences on GMD incidence between groups and virus load and OGTT blood sugar correlation were compared. Results The incidence of GDM of HBV DNA (+) or (-) group was 16.77% and 17.71%, which is higher than that in HBV group (10.27%). The difference is significant (P < 0.05). The correlation index between HBV DNA and fasting blood-glucose is r = 0.005, P = 0.610, the result of which is not statistically significant. But correlation index between HBV DNA and blood sugar at 1 h , 2 h are r = 0.082, 0.086; P = 0.000, 0.000, the result of which is statistically significant. Conclusion The oc-currence of GDM were higher in HBV DNA (+) or (-) group. The viral load is positively related with blood sugar of glucose tolerance at 1 h or 2 h.

Objective To establish a scientific and practical principle , grading standard and reasonable statistical method for evaluating the protective effect of health food to gastric mucosal injury , based on general pathology and histopathological diagnosis .Methods A methodological study was conducted on rat model of acute gastric mucosa injury induced by alcoholic through comprehensive analysis and comparing shortcomings of the current standard evaluation method, and methods of semi-quantitative analysis and corresponding information statistic processing were based on characteristics of the lesion and principles of pathology .Results Gross pathological evaluation of gastric mucosa lesion was based on the area occupied and proportion in the whole gastric mucosa .Histopathological diagnosis was based on the mucous layer depth of lesion as main determination point and other lesions as reference factors .Grades of lesion were divided into no abnormality (0), mild lesions (1 point), moderate lesions (2 points), and severe lesions (3 points). Ridit statistical method was used for pathological analysis of semi-quantitative results .Conclusion A scientific and feasible evaluation method for the protective effect of health food to gastric mucosal injury was provided from the aspects of gross pathology , histopathological evaluation method , data processing method and result determination .