Objective To study the susceptibility of Mycoplasma hominis(Mh) to several antimicrobials and Chinese medicinal herbs. Methods The minimal inhibitory concentrations(MIC) of Mh to 11 antimicrobials and 19 herbs were detected by the method of liquid microdilution. Results The sensitivity of Mh to those antimicrobials from high to low, was as follows:lincomycin, tetracycline, minocycline, levofloxacin, ciprofloxacin, ofloxacin, rifampin, spiramycin, azithromycin, erythromycin ethyl succinate and erythromycin. Among 19 herbs,Mh was sensitive to Radix Isatidis, Radix Angelicae Dahuricae, Cortex Phellodendri, Rheam Officinale, Fructus Kochiae and Herba Houttuyniae. Conclusions The susceptibility of local isolates of Mh to common antimicrobials is found out. Six Mh sensitive Chinese medicinal herbs are screened. The study provides evidences of treating Mh infection by combination of antimicrobials with Chinese medicinal herbs.

Objective:To construct a bivalent DNA vaccine against SARS-CoV-2 and influenza A virus H3N2 and to evaluate its immunogenicity in mice.Methods:The coding sequences for spike 1 (S1) protein of SARS-CoV-2 Beta variant and hemagglutinin (HA) of influenza A virus Cambodia (H3N2) strain were codon-optimized and synthesized. The two coding genes were ligated by the self-cleaving 2A peptide using over-lapping PCR to construct S1-2A-HA fragment, which was inserted into pVRC vector to construct the bivalent DNA vaccine, named as pVRC-S1-2A-HA. Indirect immunofluorescence assay (IFA) and Western blot were performed to detect the expression of S1 and HA proteins. BALB/c mice were immunized with pVRC-S1-2A-HA by intramuscular injection and electroporation. The humoral immune responses induced in mice were detected by indirect ELISA, pseudovirus neutralization assay and hemagglutination inhibition assay. Cellular immune responses were detected by IFN-γ ELISPOT, intracellular cytokine staining (ICS) and cytometric bead array (CBA).Results:The bivalent DNA vaccine pVRC-S1-2A-HA could express S1 and HA proteins in vitro. Specific cellular immune responses against S1 protein and specific IgG antibody against HA protein were significantly induced in mice with single-dose immunization. The antigen-specific immunity was significantly enhanced after booster immunization. The geometric mean titer (GMT) of specific IgG antibody increased to 3 251 for S1 protein and 45 407 for HA protein after two-dose immunization. Moreover, the S1-specific T cells increased to 1 238 SFC/10 6 cells. ICS results indicated that the booster vaccination induced CD4 + T and CD8 + T cells to produce IL-2, IFN-γ and TNF-α in mice. The secretion of various cytokines including IL-2, IL- 4, IL-6, IL-10 and IFN-γ in mouse splenocytes was induced after single-dose immunization. Conclusions:A bivalent DNA vaccine against SARS-CoV-2 and influenza A virus H3N2 was constructed and could induce S1- and HA-specific humoral and cellular immune responses in mice, suggesting the great potential of it for further development and application.

Objective:Using clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated protein 9 (Cas9) technology to edit Vaccinia virus (VACV) thymidine kinase (TK) Region for targeted recombination to establish an efficient vaccinia virus insertion recombination technology.Methods:We designed and synthesized guide RNAs(gRNA)targeting the TK region and then cloned individual gRNA into the PX458 vector that removes nuclear localization signals, and modified the original TK region recombinant plasmid. The gRNA and Cas9 co-expression plasmids were transfected into 293T cells separately to mediate the homologous recombination of vaccinia virus (VACV) and TK region recombination plasmid, and then the rate of viral recombination was evaluated by the appearance of blue and white spots.Results:The recombination efficiency mediated by the gRNA sequence designed and synthesized in this study is more than 1%, which is more than 10 times higher than the classical homologous recombination method .Conclusions:This study used CRISPR/Cas9 technology to establish a highly efficient recombinant vaccinia virus system, which provides technical support for pre-clinical research in vaccines or multivalent research of emerging infectious diseases, as well as tumor treatment.

Objective:We genetically modified our non-replicating vaccinia virus NTV to improve its immunogenicity.Methods:We constructed NTV-modified strain NTV-ΔF1L-C7L by homologous recombination of vaccinia virus based on CRISPR-Cas9 technology by inserting the C7L gene while deleting the F1L gene. The recombinant virus NTV-ΔF1L-C7L was then immunized with 10 7 PFU in BALB/c mice, and the levels of humoral and cellular immunity induced by NTV-ΔF1L-C7L were detected by ELISA and ELISpot method, respectively, and the levels of neutralizing antibodies were determined by the phage-reduced neutralization assay. Results:The PCR and western- blot identification proved that the F1L gene of the constructed NTV-modified strain NTV-ΔF1L-C7L was missing, while the C7L gene was inserted back in the region, and the C7L gene could be expressed normally, indicating that the recombinant virus was constructed correctly. After immunization of mice with NTV-ΔF1L-C7L, ELISA result showed that the recombinant virus NTV-ΔF1L-C7L induced a higher level of IgG antibody than NTV; ELISpot result also showed that the recombinant virus was able to induce a higher level of IFN-γ; and the result of plaque reduction neutralization test showed that the recombinant virus was able to induce a higher level of IFN-γ antibody than that of NTV.Conclusions:We correctly constructed the NTV gene-modified strain NTV-ΔF1L-C7L, which induced stronger humoral and cellular immunity compared with NTV, and provided reference data for the research and development of replacement products for smallpox or monkeypox vaccines.

Objective:To improve the consistency of test results through reducing inter-laboratory variation in SARS-CoV-2 antibody detection with WHO SARS-CoV-2 antibody candidate international standard (IS, sample G) and antibody reference panel (samples E, F, H, I, J).Methods:Ten WHO samples (A-J) including the candidate IS and reference panel were evaluated using different methods, such as microneutralization tests based on live SARS-CoV-2, pseudovirus neutralization assay and commercial ELISA kits. The test results were compared using statistical analysis.Results:Using IS (sample G) as a reference, the relative concentrations of other samples could be determined with less variation. ELISA and pseudovirus neutralization assay had consistent results with those obtained with the microneutralization test based on SARS-COV-2 strain HB02. Weakly positive samples could be detected only by a certain kit.Conclusions:The availability of an IS for antibodies would facilitate the standardization of SARS-CoV-2 antibody detection methods. The reference panel fitted all the assays based on the SARS-CoV-2 prototype Wuhan strain. Pseudovirus neutralization assay and ELISA could be used as alternatives to live SARS-CoV-2-based neutralization test to some extent.

Objective:To study the cell morphological changes and related molecular mechanisms of non-replicating vaccinia virus NTV infection with human cells and to provide a scientific basis for the further optimization, transformation and application of NTV vectors.Methods:HeLa cells were infected with vaccinia virus Tiantan strain VTT and non-replicating vaccinia virus NTV, and the morphological changes of cells were observed. Then cells were harvested, and rRNA break levels were detected by electrophoresis and the molecular signals associated with apoptosis were detected by Western blotting, and the pathways and mechanisms of NTV-induced early apoptosis were preliminarily determined.Results:In this study, in terms of cell morphology, it was observed that cells infected with NTV were able to have cell rounding, wrinkles and other lesions at an earlier time compared with VTT. DAPI staining showed that NTV-infected nuclei exhibited high chromatin aggregation, marginalization, and disintegration over time. The rRNA fracture level test result indicate that rRNA has been broken and degraded after 16 hours of NTV infection. The Western blotting test result showed that the molecular signals of PARP, caspase-3 and caspase-9 that were stronger than in normal cells could be detected in NTV-infected HeLa cells, but there was no significant increase in caspase-8, while the result of VTT were the opposite of those in NTV.Conclusions:NTV can induce apoptosis in the early stage and provide a theoretical basis for the modification of vaccinia vectors.

Objective:To develop a recombinase-aided amplification (RAA)-clustered regularly interspaced short palindromic repeats(CRISPR)/Cas12a-based nucleic acid assay for monkeypox virus with high specificity and sensitivity.Methods:RAA primers and CRISPR RNA (crRNA) were designed based on the known conserved regions of the monkeypox virus gene and synthesized, and specific crRNAs were screened using fluorescence detection. The sensitivity and specificity of the detection system were evaluated.Results:An RAA-CRISPR/Cas12a-based nucleic acid assay for monkeypox virus was developed with a sensitivity of 2.5 copies/reaction and high specificity without cross-reactivity with ectromelia virus and vaccinia virus.Conclusions:An RAA-CRISPR/Cas12a-based nucleic acid assay for monkeypox virus was established, which would provide a powerful tool for efficient, rapid and specific detection of monkeypox virus.

Objective:Through the study of the cell biological characteristics and virulence in mice in vivo of three non-replicating vaccinia virus modified strains to provide reference for the development of smallpox/monkeypox vaccine replacement products.Methods:Replicating vaccinia virus Tiantan strain VTT and non-replicating Tiantan Vaccinia Strain NTV were studied in BHK-21/CEF and its modified strains NTV-C7L, NTV-△F1L-C7L, NTV-K1L were amplified, purified, and identified by Western blotting. The virulence and diffusivity of each strain in cells were evaluated by immune-plaque assay. The replication dynamics curves were used to compare the replication differences between the strains, and the weight loss was observed by intranasal route in the mouse model to compare the virulence levels of the viruses.Results:In this study, Western blotting result proved that the amplified and purified vaccinia virus strains were correct. Immunophagocytosis and replication kinetics showed that the replication capacity of the three NTV modified strains in CEF was similar to that of NTV. The diffusion ability and replication ability between Vero cells were improved, but the replication multiple was less than 100 times. The replication level of MRC-5 was significantly enhanced compared with that of NTV, and the replication ratio of NTV-C7L was more than 20000 times. The virulence in mice showed that the body weight of the three NTV modified strains had no statistical significance compared with that of NTV.Conclusions:The three NTV modified strains recovered their replication ability in human MRC-5 cells, but their virulence in mice was similar to that of NTV, which provided the preliminary conditions for being candidate strains of smallpox/monkeypox vaccine replacement products.

Objective:To investigate the influence of HBV infection on the prevalence of fatty liver disease in Jinchang cohort and provide theoretical evidence for the prevention and treatment of fatty liver disease.Methods:Epidemiological investigation, laboratory examination and abdominal ultrasound were conducted in the baseline population of Jinchang cohort to collect the basic data, the differences in the prevalence of fatty liver disease under different HBV infection patterns were described and compared and the influence of different HBV infection patterns on the prevalence of fatty liver disease were evaluated by using logistic regression analysis.Results:The baseline Jinchang cohort population totaled 45 605, including 27 917 males and 17 688 females. The male to female ratio was 1.6∶1. The mean age of the overall population was 46.49 years. Among the 8 common HBV infection modes in the Jinchang cohort, the prevalence of fatty liver was low in HBsAg, HBeAg and HBcAb positive, HBsAg and HBcAb positive, and HBsAg, HBeAb and HBcAb positive groups. For 4 serum markers of HBV infection, the prevalence of fatty liver disease in HBsAg and HBeAg positive groups was lower than that in HBsAg and HBeAg negative groups. Logistic regression analysis showed that being HBsAg and HBcAb positive ( OR=0.61, 95% CI: 0.39-0.98) and HBsAg, HBeAg and HBcAb positive ( OR=0.52, 95% CI: 0.30-0.89) could reduce the risk for fatty liver disease. Conclusion:Acute HBV infection reduces the prevalence of fatty liver disease, and the reason may be related to the disturbance of the body's fat metabolism by active HBV replication.

Objective:To explore the influencing factors for non-alcoholic fatty liver disease (NAFLD) in Jinchang cohort, and provide scientific basis for the prevention and control of NAFLD.Methods:A total of 20 051 patients without fatty liver at baseline survey and met the inclusion criteria in Jinchang cohort were selected as study subjects. Prospective cohort study and Cox regression analysis were used to investigate the influencing factors for NAFLD, and the dose-response relationship between related biochemical indicators and NAFLD risk was studied by restricted cubic spline method.Results:The incidence of NAFLD was 42.37/1 000 person years. Multivariate Cox regression analysis showed that being worker and technical personnel (being worker: HR=0.84,95% CI:0.70-0.99;being technical personnel: HR=0.73,95% CI:0.56-0.95), tea drinking (current drinking: HR=0.86,95% CI:0.78-0.94;previous drinking: HR=0.52,95% CI: 0.31-0.86), exercise (occasionally: HR=0.79, 95% CI: 0.68-0.91;frequently: HR=0.60,95% CI:0.52-0.69), low body weight ( HR=0.10, 95% CI: 0.05-0.22), daily intake of dairy products >300 ml/day ( HR=0.78, 95% CI: 0.71-0.87) and HBV infection ( HR=0.77, 95% CI: 0.60-0.99) were the protective factors for NAFLD, while being internal or office workers ( HR=1.84, 95% CI: 1.46-2.31), income ≥2 000 yuan (2 000- yuan: HR=1.32, 95% CI: 1.04-1.66; ≥5 000 yuan: HR=1.72, 95% CI:1.11-2.66), bachelor degree or above ( HR=1.35,95% CI:1.03-1.76), overweight ( HR=2.31, 95% CI:2.08-2.55), obesity ( HR=3.95, 95% CI: 3.42-4.56), impaired fasting blood glucose ( HR=1.31, 95% CI:1.17-1.47), diabetes ( HR=1.53, 95% CI: 1.30-1.80), increased TC ( HR=1.37,95% CI:1.24-1.52), increased TG ( HR=1.79,95% CI: 1.62-1.98), decreased HDL-C ( HR=1.29, 95% CI: 1.14-1.45), increased ALT ( HR=1.13, 95% CI: 1.01-1.26) and high-fat diet ( HR=1.24, 95% CI: 1.11-1.40) were the risk factors for NAFLD. Moreover, TC, TG, HDL-C, ALT and FPG all showed good dose-response relationship with the incidence of NAFLD. Conclusion:Occupation, education level, income level, tea drinking, exercise, BMI, FPG, blood lipid, ALT, HBV infection and diet were related to the incidence of NAFLD.