Objective:To investigate the mosquito-borne viruses carried by mosquito specimens collected from Huachuan county and Huanan county in Heilongjiang province.Methods:Mosquito samples were collected locally in 2023 and processed in the laboratory. Homogenates of the mosquitoes were inoculated into cells for virus isolation, followed by molecular and bioinformatics analyses of the viral isolates.Results:In 2023, ten viral isolates were obtained from Anopheles sinensis specimens collected in Heilongjiang province, China. Among these isolates, one was identified as Culex flavivirus (CxFV), one as Menghai rhabdovirus (MRV), and eight as Nam Dinh virus (NDiV). The phylogenetic analysis showed that CxFV belongs to genotype I and is clustered with the strains isolated from Liaoning province in 2011 and Ningxia Hui autonomous Region in 2019 in the same evolutionary branch, with amino acid similarity ranging from 98.2% to 99.2% and nucleotide similarity ranging from 98.8% to 99.2%. The MRV strain belongs to the same evolutionary subclade as the strain detected in Guangdong, with both nucleotide and amino acid similarity of 98.0%. Eight NDiV isolates clustered with the South Korean isolates on the same evolutionary branch, forming an independent evolutionary sub-branch. The nucleotide similarity among these eight isolates ranged from 98.5% to 99.7%, while the amino acid similarity ranged from 98.1% to 99.7%. In comparison, when matched with other NDiV isolates from China, the nucleotide similarity of these eight isolates ranged from 94.1% to 97.8%, and the amino acid similarity ranged from 93.5% to 97.7%.Conclusions:This study represents the first isolation of CxFV, MRV, and NDiV in Heilongjiang province, China, and the findings provide fundamental data for the prevention and control of mosquito-borne viral diseases in this region.

Objective:To establish a method for the rapid detection of varicella-zoster virus (VZV) by recombinase-aid amplification (RAA) combined with Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a system.Methods:Clinical samples of suspected herpes zoster in Shandong province and Shanghai from 2023 to 2024 were collected, nucleic acids of positive samples were extracted, RAA-specific primers and crRNA (CRISPR RNA, crRNA) were designed for the conserved region of VZV, and the fluorescence intensity generated by Cas12a non-specific cleavage of single-stranded fluorescent probes was used to screen highly sensitive crRNAs and optimize the concentrations of crRNA, Cas12a and ssDNA probes. The sensitivity and reproducibility of the RAA-CRISPR/Cas12a detection method were evaluated by using synthesized plasmids and clinical samples, and the specificity of the method was evaluated by using other viral nucleic acids. The method was used to detect clinical samples by using the method and quantitative real-time PCR (qPCR) method, and the detection rate and consistency of the two method were compared.Results:The highly sensitive crRNA-4 was screened from the four crRNAs designed, and a VZV detection method for RAA-CRISPR/CAS12a based on fluorescence intensity measurement was established, which could be detected at 37℃ in 45 min, and the sensitivity of the detection could reach 10 copies/μL, a minimum clinical sample with a Ct value of 38.980 can be detected. It has high specificity and no cross-reactivity with Adenovirus 7, Herpes simplex virus type I, Herpes simplex virus type II, Coxsackieviruses A16, Cytomegalovirus, Epstein-Barr virus, Measles virus, Mumps virus, Enterovirus 71, Japanese encephalitis virus genotype 5. It has good stability, and can be successfully detected in low, medium and high concentrations of viral positive plasmids with good consistency. The detection rate of the clinically positive samples was 100%, which was completely consistent with the qPCR test result.Conclusions:RAA isothermal amplification technology combined with CRISPR-CAS12a technology was used to establish an accurate method for the detection of VZV virus, which was highly sensitive, specific, and had low requirements for experimental conditions, and could be completed within 45 min, which could provide strong technical support for the early detection of VZV.

Objective:To investigate the mosquito-borne viruses carried by mosquito specimens collected from Huachuan county and Huanan county in Heilongjiang province.Methods:Mosquito samples were collected locally in 2023 and processed in the laboratory. Homogenates of the mosquitoes were inoculated into cells for virus isolation, followed by molecular and bioinformatics analyses of the viral isolates.Results:In 2023, ten viral isolates were obtained from Anopheles sinensis specimens collected in Heilongjiang province, China. Among these isolates, one was identified as Culex flavivirus (CxFV), one as Menghai rhabdovirus (MRV), and eight as Nam Dinh virus (NDiV). The phylogenetic analysis showed that CxFV belongs to genotype I and is clustered with the strains isolated from Liaoning province in 2011 and Ningxia Hui autonomous Region in 2019 in the same evolutionary branch, with amino acid similarity ranging from 98.2% to 99.2% and nucleotide similarity ranging from 98.8% to 99.2%. The MRV strain belongs to the same evolutionary subclade as the strain detected in Guangdong, with both nucleotide and amino acid similarity of 98.0%. Eight NDiV isolates clustered with the South Korean isolates on the same evolutionary branch, forming an independent evolutionary sub-branch. The nucleotide similarity among these eight isolates ranged from 98.5% to 99.7%, while the amino acid similarity ranged from 98.1% to 99.7%. In comparison, when matched with other NDiV isolates from China, the nucleotide similarity of these eight isolates ranged from 94.1% to 97.8%, and the amino acid similarity ranged from 93.5% to 97.7%.Conclusions:This study represents the first isolation of CxFV, MRV, and NDiV in Heilongjiang province, China, and the findings provide fundamental data for the prevention and control of mosquito-borne viral diseases in this region.

Objective:To establish a method for the rapid detection of varicella-zoster virus (VZV) by recombinase-aid amplification (RAA) combined with Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a system.Methods:Clinical samples of suspected herpes zoster in Shandong province and Shanghai from 2023 to 2024 were collected, nucleic acids of positive samples were extracted, RAA-specific primers and crRNA (CRISPR RNA, crRNA) were designed for the conserved region of VZV, and the fluorescence intensity generated by Cas12a non-specific cleavage of single-stranded fluorescent probes was used to screen highly sensitive crRNAs and optimize the concentrations of crRNA, Cas12a and ssDNA probes. The sensitivity and reproducibility of the RAA-CRISPR/Cas12a detection method were evaluated by using synthesized plasmids and clinical samples, and the specificity of the method was evaluated by using other viral nucleic acids. The method was used to detect clinical samples by using the method and quantitative real-time PCR (qPCR) method, and the detection rate and consistency of the two method were compared.Results:The highly sensitive crRNA-4 was screened from the four crRNAs designed, and a VZV detection method for RAA-CRISPR/CAS12a based on fluorescence intensity measurement was established, which could be detected at 37℃ in 45 min, and the sensitivity of the detection could reach 10 copies/μL, a minimum clinical sample with a Ct value of 38.980 can be detected. It has high specificity and no cross-reactivity with Adenovirus 7, Herpes simplex virus type I, Herpes simplex virus type II, Coxsackieviruses A16, Cytomegalovirus, Epstein-Barr virus, Measles virus, Mumps virus, Enterovirus 71, Japanese encephalitis virus genotype 5. It has good stability, and can be successfully detected in low, medium and high concentrations of viral positive plasmids with good consistency. The detection rate of the clinically positive samples was 100%, which was completely consistent with the qPCR test result.Conclusions:RAA isothermal amplification technology combined with CRISPR-CAS12a technology was used to establish an accurate method for the detection of VZV virus, which was highly sensitive, specific, and had low requirements for experimental conditions, and could be completed within 45 min, which could provide strong technical support for the early detection of VZV.

Objective:This study conducted mosquito-borne viruses RNA screening and analysis of virus evolution characteristics on mosquito specimens collected in 2023 from Hunchun city, Jilin province, China.Methods:Firstly, morphological method were employed for mosquito specimen classification. Then, real-time fluorescence quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to detect the RNA of six mosquito-borne viruses in the collected mosquitos, i. e., Banna virus (BAV), Kadipiro virus (KDV), Liaoning virus (LNV), Tahyna virus (TAHV), Getah virus (GETV) and Japanese encephalitis virus (JEV). And by sequencing, the viral genome sequence of positive samples was obtained.Results:A total of 5490 mosquito specimens were collected from Hunchun city, Jilin province, included 4400 Aedes vexans (80.15%), 1090 Anopheles sinensis (19.85%). A total of 41 groups were obtained by mixing samples according to the time, location, and mosquito species collected. qRT-PCR result showed that only the Aedes vexans sample with the number JLHC2321 was tested positive for LNV, while the remaining samples were tested negative for the detected viruses. According to the phylogenetic analysis of the segment 10 gene, this LNV strain had the closest genetic relationship with NE9731 and belonged to the type II branch. Meanwhile, the amino acid sequence analysis based on the coding sequence (CDS) in the segment 10 showed that JLHC2321 only had 2 amino acid differential sites with the GII reference strain NE9731.Conclusions:This study detected LNV for the first time in Aedes vexans in Hunchun city, and our result provide important basic data for the monitoring and prevention strategies of mosquito-borne viruses in the region.

Objective:To investigate the species and distribution of mosquito-borne arboviruses in the southeastern part of Gansu province.Methods:In 2023, mosquitoes were collected using ultraviolet lights in Longnan and Tianshui regions of Gansu province. After classification by morphology, about 50 are only 1 batch. RT-qPCR was used to detect the RNA of Japanese encephalitis virus (JEV), Banna virus (BAV), Getah virus (GETV), Culex flavivirus (CxFV) and Tahyna virus (TAHV). The genomes of the positive samples were sequenced and the genetic evolution of the virus genomes were analyzed by bioinformatics software.Results:In total, there were 8 176 mosquitoes from 4 genera and 9 species collected from Longnan and Tianshui from June to August 2023. Culex tritaeniorhynchus was the most common species with 55.80% (4 562/8 176) of the total mosquitoes collected, followed by 16.43% (1 343/8 176) of Culex pipiens pallens. A total of 263 batches of samples were obtained, and the nucleic acid test showed that 1 batch was positive for JEV, 2 batches were positive for BAV, 3 batches were positive for GETV and 25 batches were positive for CxFV. Conclusions:Culex tritaeniorhynchus was the dominant mosquito species in the southeastern part of Gansu province, and local mosquitoes carried a variety of arboviruses.

Objective:To understand the situation of arboviruses carried by mosquito specimens in Daozhen county, Guizhou province.Methods:In July 2023, mosquito specimens were collected in Daozhen county, Guizhou province, using photocatalytic mosquito trap method. Reverse transcription polymerase chain reaction (RT-PCR) technology was used to detect the types of viruses carried by mosquitoes, and phylogenetic trees were constructed using the neighbor-joining method to analyze the phylogenetic position of the detected viruses.Results:A total of 5 313 mosquito specimens belonging to 2 genera and 2 species were collected in Daozhen county, Guizhou province, including 3 953 Culex tritaeniorhynchus, 1 355 Armigeres subalbatus, and 5 other mosquito species. The specimens were divided into 54 batches according to their species for grinding, nucleic acid extraction, and testing. Among them, 6 batches of Cx. tritaeniorhynchus specimens tested positive for flavivirus genus using universal primers, and further identification revealed that 5 batches were positive for Japanese encephalitis virus (JEV) nucleic acid, and 1 batch was positive for Tembusu virus (TMUV) nucleic acid. Phylogenetic analysis showed that the detected JEV strains were all genotype I and fell within the same evolutionary branch; the detected TMUV was located on the third branch of the evolutionary tree, with the main host source of the strains on this branch being mosquitoes. Conclusions:In the mosquito specimens collected in Daozhen county, Guizhou province in 2023, genotype I JEV and TMUV were detected, with TMUV being detected for the first time in mosquitoes in Guizhou province. It is essential to enhance the surveillance of JEV and TMUV to mitigate the potential public health risks they pose.

Objective To evaluate the antioxidant function of Chrysanthemum morifolium from different origins and to identify their antioxidant material basis.Methods The HPLC fingerprints of the water extracts of C.morifolium from different origins were established.The antioxidant activities of C.morifolium were assayed by measuring the 2.2-diphenyl-l-picrylhydrazyl(DPPH),hydroxyl radical,ABTS,superoxide anion radical scavenging capacity and ferric ion reducing capacity FRAP.Entropy-weighted TOPSIS was used to calculate the weighting coefficients of the single indexes.Grey relational analysis(GRA)and partial least squares were used for spectrum-effect analysis to identify the antioxidant material basis of C.morifolium.Results A total of 16 common peaks were discovered in the fingerprint of the water extracts of 10 batches of C.morifolium,among which 13 common components were identified.All the C.morifolium samples had good antioxidant capacity,and the results of entropy-weighted TOPSIS analysis showed that the ranking of total antioxidant potency of 10 batches of C.morifolium was follows:S1＞S8＞S3＞S5＞S4＞S10＞S7＞S2＞S9＞S6.The peaks of 1-5,9,10,12,14 were positively correlated with the antioxidant activity and the variable influence on projection(VIP)values were greater than 1.The correlation coefficients of these nine peaks in GRA were all greater than 0.7.Conclusion The entropy-weighted TOPSIS method combined with the spectrum-effect analysis could be used to screen out the antioxidant material basis of C.morifolium and the results provide a basis for establishing quality assessment system for C.morifolium based on Quality-markers thus improving the quality control level.

OBJECTIVE To explore the protective effects and potential mechanisms of Hirudo on mice with non-alcoholic fatty liver disease （NAFLD） in mice. METHODS The male ApoE－/－ mice were randomly divided into the model group and Hirudo low- dose and high-dose groups （0.45， 0.9 g/kg）， with 10 mice in each group； another 10 wild-type male C57BL/6J mice were chosen as the control group. The control group was fed with basal maintenance chow and the remaining groups were fed with high-fat chow for 12 weeks to establish the NAFLD model. Each administration group was given corresponding solution intragastrically， once a day， for 8 consecutive weeks. In the 13th week， the body weight and liver weight of mice in each group were measured after the last medication， and the liver index was calculated； the serum levels of nuclear factor-κB （NF-κB）， tumor necrosis factor-α （TNF- α）， interleukin-1β （IL-1β）， IL-6， total cholesterol （TC）， triglyceride （TG）， low-density lipoprotein cholesterol （LDL-C） and high-density lipoprotein cholesterol （HDL-C） were detected； the liver pathomorphological changes were observed； the protein expressions of peroxisome proliferator-activated receptor γ（PPARγ） and silence information regulator type 1 （SIRT1） were detected. RESULTS Compared with the control group， the liver tissue of mice in the model group showed more fat vacuoles and infiltration of inflammatory cells， with significant lipid accumulation； the body weight， liver weight and liver index of the mice， and serum levels of NF-κB， TNF-α， IL-1β， IL-6， TC， TG and LDL-C significantly increased， while the serum level of HDL-C， the protein expressions of PPARγ and SIRT1 in liver tissues significantly decreased （P＜0.01）. Compared with the model group， the pathological changes in liver tissue of mice were all relieved in Hirudo low-dose and high-dose groups； the body weight， liver weight and liver index， the serum levels of NF-κB， TNF-α， IL-1β， IL-6， TC， TG and LDL-C decreased significantly， while the serum level of HDL-C， the protein expressions of PPARγ and SIRT1 in liver tissue all increased significantly （P＜0.05 or P＜0.01）. CONCLUSIONS Hirudo can regulate liver lipid metabolism and inhibit inflammation by activating the protein expressions of PPARγ and SIRT1， thus having a significant ameliorative effect on NAFLD.

Objective:To analyze the growth characteristics of different genotypes of Japanese encephalitis virus (JEV) in different cell lines, and to provide scientific basis for the selection of cell lines in the study of JEV.Methods:BHK-21, Vero, C6/36, PK-15, DF-1, N2a, SH-sy5y and MDCK cell lines were selected. The proliferation ability of genotype 1 (NX1889 strain), genotype 3 (P3 strain) and genotype 5 (XZ0934 strain) JEV in these cell lines was evaluated by plaque assay and RT-qPCR.Results:Significant cytopathogenic effects (CPE) were observed in BHK-21, Vero, C6/36, DF-1, N2a and PK-15 cell lines across all three JEV genotypes. However, no significant differences in CPE characteristics were observed within the same cell line. SH-sy5y and MDCK cell lines did not show significant CPE, but virus proliferation was detected in SH-sy5y cell line, while MDCK cell line were found to be insensitive to JEV. No significant difference was observed in the proliferation curves of G1, G3 and G5 JEV in BHK-21, Vero and SH-sy5y cell lines. In C6/36 and PK-15 cell lines, the titer of G1 JEV was higher than that of G3 and G5. In DF-1 cell line, G5 demonstrated a higher titer than the other two genotypes, whereas in N2a cell line, G5 showed a lower titer than the other two.Conclusions:There are differences in the proliferation of three different genotypes of JEV in different cell lines, which can provide reference for the study of JEV in different directions.