With the global development of the research of medicine,more and more new drug safety evaluation institutions have been certified by Good Laboratory Practices (GLP) and Association for Assessment and Accreditation of Laboratory Animal Care International (AAALACi).Laboratory animal,which is the carrier of drug safety evaluation,its survival condition and animal welfare will directly effect the experimental results.Dealing with laboratory animal husbandry by scientific methods in two systems is the requirement to make sure the accuracy of experimental data of animal experiments.With the certification processes and practical experiences in two certification systems of Tianjin Institute of Pharmaceutical Research New Drug Evaluation Co.,Ltd.,also accompanied by experience exchangement with peers,the relationship of practices in two certification systems will be preliminarily discussed;Through strengthening the management of laboratory animal,it can help the institutions get the certificates.

Objective : To observe the clearance of smear layer on the root canal wall in different action time by scanning electron microscope (SEM), and to determine the optimal amount of time using sonically activated irrigation to wash root canal in clinic. Methods: Fifty-six ex vivo human anterior teeth with single straight root canal were selected. After routine mechanical preparation, they were divided into two experimental groups according to different irrigating agents: saline group and EDTA group. Each group was assisted by VDW sonic activation EDDY. The saline group was divided into three subgroups according to the irrigating time: 5 s, 30 s and 50 s; EDTA group was divided into six subgroups according to the irrigating time: 5 s, 10 s, 20 s, 30 s, 40 s and 50 s. The control group did not undergo root canal irrigation. After irrigation, the root was cut longitudinally. The smear layer of crown, middle and apical of root canal wall was observed by SEM. Results: After irrigating for 30 seconds, there was a significant difference between the normal saline group and the control group and the 5 second group (P<0.05), and there was no difference in the middle and apical part (P>0.05). After 50 seconds, there was a significant difference in the score of the smear layer between the apical area and the other groups (P<0.05). After irrigating for 5 seconds or 10 seconds in EDTA group, there was a significant difference between the scores of the crown and middle area of the root canal and the control group (P<0.05), and there was no significant difference in the apical area (P>0.05). There was a significant difference between the 20-40 second group and the first two groups (P<0.05). There was a significant difference between the 50 second group and the other groups (P<0.05). Comparing the cleaning effect on the smear layer after 50 seconds of irrigating between the two experimental groups, the whole root canal showed significant statistical difference (P<0.05). Conclusion The EDTA-assisted sonic activated device used for 50 seconds has the best cleaning effect.

Objective:To systematically review the progress, advantages, disadvantages, precautions and future trends of virtual simulation technology used in epidemiology teaching.Methods:A systematical literature retrieval was conducted by using PubMed, Web of Science, Embase, China National Knowledge Infrastructure, Wanfang Data and VIP Paper Check System with key words of epidemiology, teaching and virtual simulation, and the literatures included were screened and classified with narrative integration method. Chinese virtual simulation teaching platforms were used to select the literatures about existing epidemiology virtual simulation teaching projects for integration and analysis.Results:A total of 22 articles were included (7 in Chinese and 15 in English), most of which were teaching projects for students majoring in Public Health. We also found 24 national first-class courses and 21 provincial first-class courses in virtual simulation of epidemiology in China. The application of virtual simulation technology in epidemiology education is still in its infancy, and the interaction degree is mostly moderate. It is mainly used in three scenarios: improving the visualization degree of complex concepts and structures, training the operational skills through low-risk and low-cost virtual environment, serving as an effective supplement to the teaching of epidemiological field investigation and response to public health emergencies. In terms of effect, it is conducive to students' understanding of epidemiology related phenomena and principles, and has the advantages of breaking through time and space constraints, reducing teaching costs and risks, improving students' attention and satisfaction and so on. However, it also faces the lack of foundation in the initial stage, and some students have problems such as psychological and physiological discomfort. In the future, we need to optimize the development process, program design and so on. At the same time, we should conduct more in-depth research on cost calculation, effect evaluation and curriculum integration.Conclusions:The application of virtual simulation technology in epidemiology education is an important part of training high-level applied public health talents. We encourage to actively carry out virtual simulation teaching in epidemiology, and train public health talents with Chinese characteristics.

BACKGROUND: Vaccination has been shown effective in controlling the global coronavirus disease 2019 (COVID-19) pandemic and reducing severe cases. This study was to assess the flare and change in disease activity after COVID-19 vaccination in patients with stable rheumatoid arthritis (RA). METHODS: A prospective cohort of RA patients in remission or with low disease activity was divided into a vaccination group and a non-vaccination group based on their COVID-19 vaccination status. Each of them was examined every 3 to 6 months. In the vaccination group, disease activity was compared before and after vaccination. The rates of flare defined as disease activity scores based on 28-joint count (DAS28) >3.2 with ΔDAS28 ≥0.6 were compared between vaccination and non-vaccination groups. RESULTS: A total of 202 eligible RA patients were enrolled. Of these, 98 patients received no vaccine shot (non-vaccination group), and 104 patients received two doses of vaccine (vaccination group). The median time interval from pre-vaccination visit to the first immunization and from the second dose of vaccine to post-vaccination visit was 67 days and 83 days, respectively. The disease activity scores at pre-vaccination and post-vaccination visits in the vaccination group patients were similar. At enrollment, gender, RA disease course, seropositivity, and disease activity were comparable across the two groups. Flare was observed in five (4.8%) of the vaccination group patients and nine (9.2%) of the non-vaccination group patients at post-vaccination assessment ( P  = 0.221). In terms of safety, 29 (27.9%) patients experienced adverse events (AEs) after vaccination. No serious AEs occurred. CONCLUSIONS COVID-19 vaccinations had no significant effect on disease activity or risk of flare in RA patients in remission or with low disease activity. Patients with stable RA should be encouraged to receive the COVID-19 vaccination.
Humans ; Arthritis, Rheumatoid ; Cohort Studies ; COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; East Asian People ; Prospective Studies ; Vaccination/adverse effects*

Objective To investigate the accuracy and feasibility of shear wave elastography(SWE)combined with superb microvascular imaging(SMI)for the differential diagnosis of benign and malignant thyroid nodules.Methods A total of 190 patients with thyroid nodu-les detected in the Ultrasound Department of our hospital from January 2021 to December 2022 who underwent ultrasound-guided fine-needle aspiration biopsy or exhibited postoperative histopathological improvement were selected as the study subjects.Among them,a total of 224 thyroid nodules(74 benign and 150 malignant nodules)were detected,all of whom underwent thyroid ultrasonography,SWE,and SMI.The parameters related to the Young's modulus of the tissue as well as the condition of fine blood flow and perforating vessels were calculated.Using histopathological results as the gold standard to construct receiver operating characteristic(ROC)curves,observe the effectiveness of SWE combined with SMI in the differential diagnosis of thyroid nodules,and compare the efficacy of different examination methods in the diagnosis of thyroid nodules.Results There were significant differences in the internal composition,echo,margin,cal-cification,and aspect ratio between the benign and malignant thyroid nodules(all P<0.05);however,there was no significant difference in the average diameter of the benign and malignant nodules(P>0.05).There were statistically significant differences in maximum elas-ticity,mean elasticity,elasticity ratio,microvascular score,peak shear wave velocity,and average shear wave velocity between the benign and malignant thyroid nodules(all P<0.05).The ROC curve showed that the area under the curve of the maximum elastic value was the highest,while the optimal diagnostic threshold was 29.52 kPa.The optimal diagnostic threshold for the microvascular flow score was 2.3 points.In terms of diagnostic efficacy,SWE combined with SMI showed the highest sensitivity(94.67%)and specificity(94.59%).Conclusion SWE combined with SMI can further improve the diagnostic efficiency of benign and malignant thyroid nodules and achieve quantitative evaluation and dynamic observation of lesions,which has application and promotion value.

Objective:To establish a rapid method for the detection of varicella-zoster virus (VZV) by recombinase-aid amplification (RAA).Methods:The whole genome sequences of VZV were downloaded from the global shared database for comparison and analysis. Specific primers and probe were designed for the four conserved genes respectively and the optimal combination was selected. The optimal reaction system was selected through the concentration gradient of primers and probes, and a fluorescence RAA detection method was established. The sensitivity of the method was evaluated with VZV positive plasmid standard and clinical samples with gradient dilution, the repeatability of the method was evaluated with the lowest detectable limit concentration of positive plasmid standard, and the specificity of other viral nucleic acid method was evaluated. At the same time, this method and quantitative real-time PCR (qPCR) were used to detect clinical samples and the result were compared.Results:The optimal combination of primer pair F2/R2 and probe P2 targeting open reading frame (ORF) 28 gene was selected. Considering the cost factor, the optimal primer concentration was set at 500 nmol/L and the optimal probe concentration was 280 nmol/L. The minimum detection limit was 10 1 copies/μL, and the minimum clinical positive samples with a Ct value of 36.027 could be detected, and the result of repeated experiments were consistent. The method has no cross-reaction with other viral nucleic acids. The detection rate of clinical positive samples was 93.33%, which was almost identical to that of qPCR. Conclusions:This method is simple to operate with high sensitivity, strong specificity, low requirements for experimental conditions, visual detection result, and can detect VZV nucleic acid in samples within 20 minutes, which is a rapid VZV detection method that can be considered for clinical use for detection.

Objective:To investigate the expression of epigenetic inhibitor polycomb group proteins such as enhancer of zeste homolog 1/2 (EZH1/EZH2), embryonic ectoderm development protein (EED) and suppressor of zeste 12 (SUZ12) in common cutaneous T-cell lymphomas and lymphoproliferative disorders (CTCL/LPD) .Methods:Totally, 93 paraffin-embedded skin samples of CTCL/LPD and 8 of lichen planus were collected from Hospital for Skin Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College between 2012 and 2019, and subjected to immunohistochemical staining to determine the protein expression of EZH2, EED, SUZ12 and EZH1. Statistical analysis was carried out with SPSS 25.0 software by using chi-square test and Spearman correlation analysis.Results:The 93 cases of CTCL/LPD included 44 cases of mycosis fungoides (MF), 17 natural killer/T cell lymphoma (NK/TCL), 8 primary cutaneous anaplastic large cell lymphoma (PC-ALCL), 8 lymphomatoid papulosis (LyP), 8 hydroa vacciniforme-like lymphoproliferative disorder (HV-like LPD) and 8 cases of subcutaneous panniculitis-like T cell lymphoma (SPTCL). Among the 93 CTCL/LPD cases, 83 (89.2%) were positive for EZH2, 81 (87.1%) for EED, 78 (83.9%) for SUZ12 and 37 (39.8%) for EZH1; among the 8 cases of lichen planus, 1 was positive for EZH2, all were positive for EZH1, and all were negative for EED and SUZ12. The expression of EZH2, EED, SUZ12 and EZH1 in lichen planus samples significantly differed from all the CTCL/LPD samples ( χ2 = 41.75, 39.74, 39.36, 32.83, respectively, all P < 0.001), and from MF, NK/TCL, PC-ALCL, LyP, HV-like LPD and SPTCL samples separately (α = 0.008 3, all P < 0.001). Meanwhile, the score of EZH2 expression was negatively correlated with that of EZH1 expression in the MF, NK/TCL, PC-ALCL, LyP, HV-like LPD and SPTCL tissues ( rs = -0.60, -0.68, -0.89, -0.74, -0.93, -0.80, respectively, all P < 0.05) . Conclusion:Polycomb group proteins EZH2, EED, SUZ12 and EZH1 are abnormally expressed in CTCL/LPD lesions.

Objective·To construct a probiotic(Escherichia coli Nissle1917,EcN)system(EcN@PVA-ALG)loaded on polyvinyl alcohol(PVA)/alginate(ALG)hydrogel(PVA-ALG)rich in negative hydroxyl groups,and to explore its colonization in the inflammatory site of colon and its therapeutic effect on dextran sulfate sodium salt(DSS)-induced inflammatory bowel disease(IBD).Methods·EcN suspension was added to the PVA-ALG hydrogel,and then EcN@PVA-ALG hydrogel probiotic complex was obtained after screening and centrifugation.The synthesis of PVA-ALG hydrogel was verified by rheometer.The surface charge of EcN@PVA-ALG was detected by potentiometer and the load of EcN on PVA-ALG was observed by fluorescence microscope.The absorbance of EcN@PVA-ALG at 600 nm was detected by enzyme labeling instrument.Meanwhile,the bacterial plate count of EcN@PVA-ALG complex suspension was taken to study the growth activity of EcN in EcN@PVA-ALG.The CCK-8 kit was used to assess the inhibitory ability of EcN@PVA-ALG on HEK cell proliferation.In vivo imaging system(IVIS)was used to firstly analyze the enrichment of PVA-ALG on inflammatory colon to study its inflammatory targeting property;then EcN was loaded on PVA-ALG,and IVIS was used to observe the enrichment of EcN@PVA-ALG on inflammatory colon to study its ability to colonize the inflammatory site.To establish the model of IBD mice induced by DSS,EcN@PVA-ALG group(n=5)was given 1×108CFU EcN@PVA-ALG every day for 5 d,and PVA-ALG group,EcN group,PBS group and healthy control group with 5 mice were set up.During the treatment,the body mass of the mice was recorded every day.After treatment,the colonic tissue was taken,and the length of colon was measured.The disease activity index(DAI)score was graded.The levels of inflammatory cytokines,including tumor necrosis factor-α(TNF-α),interleukin(IL)-6,IL-10 and transforming growth factor-β(TGF-β)were detected,and the pathological evaluation of colonic tissue was made by H-E staining.Results·Both PVA-ALG and EcN@PVA-ALG were negatively charged.EcN was successfully loaded onto PVA-ALG and PVA-ALG did not affect the growth viability of EcN,which contributed to the subsequent colonization of inflammatory colons.PVA-ALG had a favorable safety profile on normal cells.Compared with healthy controls,PVA-ALG had more than 2-fold enrichment effect on inflammatory colon tissue.In vitro and in vivo experiments revealed that EcN@PVA-ALG complex loaded with EcN had 8 times higher enrichment effect on inflammatory tissue than EcN without any modification.After EcN@PVA-ALG treatment,the body weight of mice recovered rapidly.The increase of DAI was significantly inhibited.The length of colon was similar to that of healthy mice.The levels of TNF-α and IL-6 decreased,while the levels of IL-10 and TGF-β increased.The crypt structure of colon tissue recovered.Conclusion·Compared to unmodified EcN,EcN@PVA-ALG promotes the colonization of EcN at inflammatory sites of colon and allows it to exert better efficacy on treating DSS-induced IBD.

[摘 要] 目的：通过生物信息学分析以及细胞生物学实验研究角蛋白6A（KRT6A）对胰腺导管腺癌（PDAC）诊断、预后判断、免疫微环境以及PDAC细胞PANC1增殖、凋亡等生物学行为的影响。方法：通过GEPIA平台整合TCGA（The Cancer Genome Atlas）数据库与GTEx（Genotype-Tissue）数据库中的数据，分析KTRT6A在PDAC组织中的表达情况，并通过CIBERSORT工具分析KRT6A表达与PDAC组织中免疫细胞浸润的关系，然后通过GSEA方法研究与KRT6A基因表达相关的肿瘤信号通路。选取长海医院病理科保存的60例PDAC组织与癌旁组织标本进行免疫组化分析，验证KRT6A在肿瘤组织中表达情况；通过干扰RNA敲减PANC1细胞中KRT6A的表达，采用CCK-8实验以及流式细胞术检测敲减KRT6A对细胞的增殖、凋亡的影响。结果：利用TCGA与GTEx数据库数据分析发现，KRT6A在人PDAC组织中呈高表达，且与患者较差的生存期存在关联（P=0.015）。利用CIBERSORT软件以及GSEA分析发现，KRT6A高表达的PDAC组织中M2型巨噬细胞浸润性升高（P=0.034），且与Wnt通路（NES:1.7359272，P<0.05）、磷酸戊糖途径（PPP）（NES:1.5613053，P<0.05）等信号通路上调有关联（P<0.05或P<0.01）；免疫组化结果进一步验证了KRT6A在PDAC组织中呈高表达（P<0.001）。增殖和凋亡实验发现，干扰KRT6A能够显著抑制PANC1细胞的增殖（P<0.05）以及凋亡（P<0.001）。结论：KRT6A在人PDAC组织中呈高表达，敲减其表达能够抑制PANC1细胞的增殖和凋亡，具有作为PDAC诊断与预后判断新靶标的潜力。

Secondary caries is one of the main reasons that affect the service life of the restoration. Compared with primary caries, secondary caries have some particularities in etiology, disease progression, clinical manifestation, clinical diagnosis, treatment and prevention. Starting from the above aspects, combined with the latest basic and clinical research on secondary caries, this paper summarizes and analyzes its pathogenesis and prevention strategies, which will lay a certain foundation for in-depth understanding of secondary caries and promoting its clinical prevention and treatment.