Tumor vaccine is one of the most promising therapeutic strategies in tumor immunotherapy. It promotes the antigen presentation process by delivering tumor antigen and then activates the anti-tumor immune response. As a new class of vaccines, messenger RNA (mRNA) vaccines can activate the immune system to achieve the purpose of immunotherapy by delivering the mRNA sequence of a specific antigen into the body and expressing the corresponding antigen protein. Compared with traditional vaccines, mRNA vaccines have the advantages of a short production cycle, high effectiveness, and strong immunogenicity. In recent years, the application of mRNA vaccines in tumor immunotherapy has attracted widespread attention, but the instability and low delivery efficiency of mRNA limit its application. Nano delivery system can effectively solve the problem of mRNA vaccine delivery, greatly promote the research process and clinical application of mRNA tumor vaccines, and has become a hot spot in the research of mRNA vaccines. In this review, we introduced the mRNA tumor vaccines, focusing on the application of nano delivery system in mRNA tumor vaccines, in order to provide new ideas and new methods for the efficient delivery of mRNA tumor vaccines and tumor immunotherapy.

Objectives: To explore the influence of exercise training on the arterial baroreflex sensitivity （BRS）and correlation between blood pressure and BRS in spontaneously hypertensive rats (SHR). Methods: Male SHR（n=20）and normotensive Wistar rats（n=20）were randomly assigned to normality group and exercise group, n=10 in each group. Rats in two exercise groups received treadmill training at a speed of 20 m/min for 60 min/d, 6 d/w for eight weeks. Systolic blood pressure (SBP) and heart rate (HR) were measured using a tail-cuff method in a conscious state. Intravenous injections of phenylephrine (PE) and sodium nitroprusside (NP) were used to induce depressor and pressor reflex respectively. The ratio of HR over mean arterial pressure (MAP) (HR /MAP) after administration of PE or NP was regarded as an index of depressor reflex sensitivity (BRS-PE) and pressor reflex sensivity (BRS-NP). Results: After eight-week exercise training, compared with SHR normality group, there were significant reduction in resting SBP [(180±8.5) mmHg vs. (163.6±10.7) mmHg] and in HR [(368.4±13.3) beats/min vs. (345.0±9.8) beats/min] in SHR exercise group, P<0.01 both. However, there was no significant difference in resting SBP between Wistar exercise and normality groups (P>0.05), compared with Wistar normality group, there was significant reduction in HR [(362.2 ± 13.0) beats/min vs. (343.9 ± 10.2) beats/min, P <0.05] in Wistar exercise group. Compared with SHR normality group, there were significant rise in BRS [BRS-PE: (0.89 ± 0.13) bpm/mmHg vs. (1.32 ± 0.22) bpm/mmHg, BRS-NP： (0.60± 0.09) bpm/mmHg vs. (1.21± 0.26) bpm/mmHg, P<0.01] in SHR exercise group, but still lower than those of Wistar normality group [BRS-PE: (1.96±0.23) bpm/mmHg, BRS-NP: (1.32±0.17) bpm/mmHg]. Pearson linear correlation analysis indicated that MAP was significantly inversely correlated with BRS (r=-0.734, P<0.01) in SHR normality and exercise group. Conclusion: Exercise training may significantly decrease SHR blood pressure; it is related to improved baroreflex sensitivity induced by exercise, indicating that enhanced baroreflex may be an important mechanism of exercise therapy in hypertensive patients.

Objective To study the relationship between static duration and bacteria reproduction of pure water from the RO purifier. Methods The original structure of RO purifier was modified by installing additional UV lights and ozone disinfector respectively. Bacteria reproduction in the effluent from RO purifier and modified RO purifier was detected after different static duration. Results The total count of bacteria in the fresh pure water was 20 cfu/ml which was up to the standard of pure drinking water CJ 94-1999. However the total count of bacteria in the pure water will be more than 50 cfu/ml after the pure water was stored inside the tank for six hours, which was not up to the standard of CJ 94-1999. Both ultraviolet rays and ozone could prolong the static duration of pure water, and the efficacy of ultraviolet rays was better than ozone. Conclusion UV light should be installed in RO purifier, the disinfected pure water by UV should be used in 16 hours after disinfection.

Objective : To investigate the injury characteristics among primary and middle school students in Panyu District, Guangzhou City, so as to provide the evidence for developing the strategies for prevention and control of injuries. Methods: The data of 6 to 18 years old primary and middle school students with initial diagnosis of injury at Panyu District Central Hospital from 2014 to 2019 were collected. The basic characteristics of injury cases, the causes, time and place of injury development were analyzed by a descriptive epidemiological method. Results: Totally 10 833 primary and middle school students with injury were reported in Panyu District from 2014 to 2019, including 7 401 boys and 3 432 girls, with a boy/girl ratio of 2.16∶1. The injury predominantly occurred in primary school students (6 903 cases, 63.72%). The causes of injury mainly included fall (4 457 cases, 41.14%), animal injury (2 593 cases, 23.94%), blunt injury (1 682 cases, 15.53%), knife/sharp instrument injury (923 cases, 8.52%) and traffic injury (731 cases, 6.75%). The place of injury development mainly included home (4 267 cases, 39.39%), school and public place (3 184 cases, 29.39%), and road/street (1 854 cases, 17.11%). The injury predominantly occurred from August to October (3 289 cases, 30.36%), and the activities at the time of injury mainly included leisure activities (3 860 cases, 35.63%), life activities (2 662 cases, 24.57%) and sports (1 929 cases, 17.81%). The characteristics of injury mainly included contusion/abrasion (4 528 cases, 41.80%), sharp instrument/bite/open injury (4 019 cases, 37.10%) and fracture (871 cases, 8.04%), and the upper limb was the main injury site (3 552 cases, 32.79%). There were 9 877 cases with mild injuries (91.18%), and 10 451 cases left hospitals after seeing a doctor (96.47%). Conclusions Fall is the main causes of injury among primary and middle school students in Panyu District, and boys and primary school students are high-risk groups for injury. Family prevention should be emphasized, and health education pertaining to injury should be intensified among students during the long holidays and leisure activities.

Objective To evaluate the diagnostic value of treponema pallidum particle agglutination (TPPA) and toludine red unheated serum test (TRUST) for the therapeutic effects of early syphilis.Methods Syphilis patients visited the Dermatological Department of Beijing Tongren Hospital, Capital Medical University from January 2012 to October 2016 were recruited, including 189 patients with early syphilis and 39 patients without clinical symptoms but with risky behavior within 3 months.Serum samples were tested by TPPA and TRUST respectively before treatment and at month 3, 6, 12 after treatment.Comparison between groups was done by χ2 test.Results Serum TPPA results of 228 patients with early syphilis prior to the treatment and within 12 months after treatment were all positive.Before treatment, TRUST tests results of 225 patients were positive, and 156 patients turned negative after 12 months of treatment with the negative conversion rate of 69.3%.The TRUST titer ≤1∶4 before treatment was defined as low-titer group, and ≥1∶8 before treatment was defined as high-titer group.There were 93 patients in the low-titer group, including 3 patients with negative results, and 90 patients with titer 1∶1-1∶4.There were 135 patients in the high-titer group.Twenty-seven patients achieved TRUST negative conversion after 3 months of treatment, among which 19.35%(18/93) with the negative conversion rate in the low-titer group and 6.67%(9/135) in the high-titer group.The difference between the two groups was statistically significant (χ2=7.10, P<0.01).Sixty-two patients converted into negative results of TRUST assay after 6 months of treatment, including 36.56%(34/93) in the low-titer group and 11.85%(16/135) in the high-titer group whose titer of 1∶1-1∶4, and 6.45%(6/93) in the low-titer group and 4.44%(6/135) in the high-titer group whose titer ≥1∶8 turned negative.The difference between the two groups was statistically significant (χ2=17.10, P<0.01).There were 67 patients converted negative detected by TRUST assay after 12 months of treatment, including 23.66%(22/93) in the low-titer group with titer of 1∶1-1∶4 and 14.81%(20/135) in the high titer group, and 1.08%(1/93) in the low-titer group and 17.78%(24/135) in the high-titer group whose titer ≥1∶8 were turned negative.The difference between the two groups was not statistically significant (χ2=1.51, P>0.05).Conclusion Serological tests combined with clinical signs can accurately diagnose early syphilis and evaluate the therapeutic effects.

Objective To study the effect of homeobox genes CDX1 and CDX2 on the phenotype of esophageal adenocarcinoma cells.Methods Esophageal adenocarcinoma cell line SEG-1 was transfected with CDX1 or CDX2 cDNA.The morphology,growth rate,division index and tumorigenicity were analyzed.Results The expression of CDX1 or CDX2 leaded to occurring adeniform-like manifestation.The growth rate,division index and tumorigenicity were reduced,especially by CDX2.Conclusion CDX1 and CDX2 all could increase differentiation of esophageal adenocarcinoma cells and reduction of its malignancy.

Objective To explore the role of miRNA-148a in bladder tumorous development and progression.Methods Ex-pression of miRNA-148a was assessed in 35 bladder carcinoma tissues and 16 non-carcinoma tissues by fluorescence quanti-tative real time PCR,and correlation with clinical features was evaluated.Target genes and transcription factors of miRNA-148a were predicted using bioinformatic analysis,then TF-miRNA-148a-target genes network diagram was built and the tar-get genes was analyzed of gene ontology enrichment and KEGG pathway.Results Expression of miRNA-148a was lower in bladder carcinoma tissues than in non-carcinoma tissues(0.000 8±0.000 2 vs 0.002 1±0.000 5)(t=2.46,P <0.05),but its expression was no statistical significance in different groups of gender,age,pathological classification,clinical stage, lymph node metastasis (P >0.05).268 target genes of miRNA-148a were predicted by three softwares at the same time,60 transcription factors were predicted and the binding sites with combination scroes above 80 was 657.The target genes of miRNA-148a was enriched in many biological processes,such as neuron differentiation,generation of neurons,neuron projec-tion development,cytoplasmic mRNA processing body,cytoplasm(P <0.001).They also participated in p53 signaling path-way,proteoglycans in cancer-homo sapiens,pathways in cancer,prostate cancer,protein processing in endoplasmic reticulum, focal adhesion and so on(P <0.05).According to TF-miRNA-148a-target genes network diagram,miRNA-148a was regula-ted by SP1,ESR1,AP1,MYC and BRCA1,genes of IGF1,P27kip1 ,NCOA1,PTEN,SERPINE1 might be regulated by miR-NA-148a.Conclusion miRNA-148a which was significantly down-regulation in bladder carcinoma tissues may be participate in bladder tumorous development and progression,bioinformatics analysis provides some ideas for further research.

Objective To investigate the expression and clinical significance of zinc finger protein 217 (ZNF217)in human pancreatic cancer.Methods 43 cases with pancreatic cancer undergoing surgery in the PLA 117 Hospital and People's Hospital of Ruian City from Apr .2011 to May.2014 were enrolled in the study . The pancreatic cancer and the corresponding tumor-adjacent tissues were collected .Real-time quantitative PCR (qRT-PCR)was applied to detect ZNF217 mRNA expression in pancreatic cancer (n=43)and the corresponding tumor-adjacent normal tissues.The protein expression of ZNF217 was measured by immunohistochemistry(IHC). The relationship between the expression of ZNF 217 and clinical features was analyzed by pearson chi-square test . Results The expression level of ZNF217 mRNA and protein was significantly higher in pancreatic cancer tissues than in adjacent normal tissues(P<0.05).The high expression of ZNF217 protein was positively correlated with perineural invasion, tumor size, lymphatic metastasis and advanced TNM stage (P<0.05).Conclusions The expression of ZNF217 is significantly higher in pancreatic cancer tissues than in tumor-adjacent normal tissues , and the upregulation of ZNF 217 is associated with clinicopathological features of tumor malignance .ZNF217 may become a new marker and effective therapeutic target in early diagnosis of pancreatic cancer .

BACKGROUND:As an important industrial solvent,benzene can cause DNA damage,chromosome aberrence,formation of DNA adducts and gene mutation. OBJECTIVE:To explore the effects of benzene on DNA and the mechanism,as well as the changes of antioxidase system it caused. DESIGN:Randomized case control study. SETTING:The Department of Clinical Laboratory of First Affiliated Hospital and Public Health College of Harbin Medical University. PARTICIPANTS:The experiment was completed in the Animal Centre in Public Health College,Harbin Medical University.Twenty-four healthy male mice of Kunming species weighed between 18 g to 22 g were chosen.The mice were provided by Experimental Animal Centre of Second Affiliated Hospital,Harbin Medical University. INTERVENTIONS:The mice were divided into control group,low dose benzene group and high dose benzene group.Inhaling benzene smoke method was used 4 hours per day to cause benzene poisoning to mice except those of the control group.The mice were executed two months later to separate marrow cells and peripheral lymphocytes and remove liver,spleen and brain to make homogenate. MAIN OUTCOME MEASURES:Single cell gel electrophoresis (SCGE) was used to assay the DNA damages of marrow cells and peripheral lymphocytes.Meanwhile,the contents of superoxide dismulase(SOD),glutathione peroxidase(GSH-Px) and malondialdehyde(MDA) in liver,spleen and brain tissues were also detected. RESULTS:The comet percentage of marrow cells and peripheral lymphocytes in two benzene poisoning groups were(83.56± 10.28),(92.54± 15.93)% ,and(41.27± 6.03)% ,(65.79± 11.62)% respectively which were much higher than those in control group[(4.13± 0.52)% ,(2.21± 0.31)% ](P< 0.01) and represented dose-response relationship.The SOD activity of liver homogenate and GSH-Px activity of high dose and low dose groups were (11 573.31± 1 938.72),(12 574.68± 1 938.72) nkat/g and (309.40± 82.85),(375.41± 55.18) nkat/g respectively which were much lower than those in control group [(16 668.67± 3 137.96),(588.62± 110.52) nkat/g] (P< 0.05).However, there was no significant difference between different dose groups. The GSH-Px activity in spleen homogenate in two experimental groups was(421.75± 124.02) and(523.10± 45.18) nkat/g respectively which was much lower than that of control group [(618.42± 57.01) nkat/g](P< 0.05) and there was significant difference between two groups (P< 0.05).In the brain homogenate of both benzene groups,the GSH-Px activity was(87.35± 19.84) and(95.02± 14.00) nkat/g respectively which was much lower than that of control group[(118.36± 7.67) nkat/g] (P< 0.05) and without difference between two groups.The MDA content in brain homogenate of high dose group was(3.99± 1.15) μ mol/mg which was much higher than that of control group [(2.58± 0.53) μ mol/g] (P< 0.05). CONCLUSION:Chronic benzene poisoning can cause DNA impairment of marrow cells and peripheral lymphocytes and reduce the activity of antioxidase.

The specific primers and Taqman probe were designed and synthesized according to the UL31 gene sequence available in GenBank(EF417996).The fragment is 76 bp.A Taq Real-time fluorescent quantitative PCR assay was established for detection of Duck Plague Virus DNA based on DNA copy obtained from attenuated vaccine strain as a positive template.The sensitivity of the test for DEV is 2.1 × 100-2.1 × 109 copies.The minimum detection limit is 2.1 copies(2.1 fg).Tissues,excrement and blood of 4 ducks challenged with DEV were detected repeatly 3 times by this method.All results were positive (3/3).The specificity of the assay was proven based on no amplification by detecting DNA from normal duck cells,duck viral hepatitis virus,Pasteurella,E.coli,S.gall inarum,Newcastle disease virus,goosling plague virus et ai.The whole process of the test could be completed within 4 hours.It brings about quantification detection of DEV DNA.