The objective of this study was to examine the effects of tributyrin(TB)on energy me-tabolism,oxidative stress and immune function in dairy cows with negative energy balance(NEB).In this study,25 perinatal Holstein cows from a dairy farm in Heilongjiang Province were selected.Five healthy cows were designated as the control group,and 20 cows with NEB were randomly di-vided into NEB control group,Propylene glycol(PG)group(300 mL PG),TB group(37.5 g TB)and PG+TB group(300 mL PG+37.5 g TB)with 5 cows in each group,and were continuously fed for 14 days.Blood samples were collected at 0,7,14 and 21 days.The indexes of oxidative stress,energy metabolism and immune function in the serum of dairy cows were quantified using commercially available kits.The results showed that compared with the NEB group,the contents of T-AOC,GSH-Px,CAT and SOD in the TB group were significantly increased,whereas the content of MDA was significantly decreased.These results indicated that TB can effectively alleviate the oxidative stress of cows with NEB.The contents of BHB,NEFA and BUN in the TB group were significantly decreased,indicating that TB can regulate energy metabolism disorders in cows with NEB.The contents of IL1β,IL-2,IL-6,IL-21,MIP-1 and IP-10 in the TB group were significantly decreased,while the contents of IgA,IgM and IgG were significantly increased.These results sug-gest that TB has shown significant effects in inhibiting inflammatory response and improving im-mune function.Furthermore,compared with the PG group,the contents of T-AOC,GSH-Px,CAT,SOD,IgA,IgM and IgG in the TB group and the PG+TB group were significantly in-creased,whereas the contents of MDA,BHB,NEFA,BUN,IL-1β,IL-2,IL-6,IL-21,MIP-1 and IP-10 were significantly decreased.These results indicated that feeding TB alone was effective in alle-viating oxidative stress,improving energy metabolism and inhibiting inflammation in dairy cows compared to feeding the traditional drug PG,and the effect of feeding a mixture of PG and TB was particularly significant.This study provides a new theoretical basis for the prevention and treat-ment of oxidative stress and immune function decline caused by perinatal cows with NEB.

Objective:To investigate the sero-conversion rate of HIV antibody and influencing factors in cross-border couples in Dehong Dai and Jingpo Autonomous Prefecture(Dehong).Methods:A cohort design was used to recruit HIV-negative people in cross-border couples in Dehong in 2017. Follow-up was conducted in 2023, and questionnaire survey and HIV test were carried out to calculate the sero-conversion rate of HIV antibody. Univariate and multivariate logistic regression models were used to analyze the influence factors for HIV infections.Results:A total of 36 278 HIV-negative persons in cross-border couples were included in the 2017 baseline survey, of whom 22 438 (61.9%) were tested in follow-up in 2023. The sero-conversion rate between 2017 and 2023 was 0.51% (115/22 438). Multivariate logistic regression analysis showed that length of marriage <6 years, Jingpo ethnic group, education level of primary school or below, drug use, illegal marriage and HIV infected spouse were the risk factors of HIV infection in male spouses, and length of marriage <6 years, Jingpo ethnic group, illegal marriage and HIV infected spouse were the risk factors in female spouses.Conclusions:The sero-conversion rate of HIV antibody in cross-border couples in Dehong was relatively high. HIV infection was mainly caused by secondary transmission in the couples, and men might also be infected through drug use. It is necessary to strengthen the registration and management of cross-border couples, especially the couples with discordant HIV infection status, and the intervention in drug users to reduce the risk for secondary transmission of HIV in the cross-border couples.

Objective:To analyze the effect of influenza vaccination on influenza cluster epidemic in primary and secondary schools in Beijing during the 2023-2024 surveillance season and provide evidence for the improvement of influenza vaccination strategies.Methods:The incidence data of influenza cluster epidemic and influenza vaccination coverage in the schools in Beijing during 2023-2024 were collected. Descriptive epidemiological methods were used to analyze cluster epidemic characteristics, and χ2 test was used to compare incidence differences between groups, and OR value and vaccine effectiveness [VE=(1- OR)×100%] were calculated. A negative binomial regression model was used to evaluate the association between school vaccination rates and cluster epidemic risk. Joinpoint regression was used to analyze trends in relative risk ( RR) with increasing vaccination coverage and to determine the optimal vaccination threshold. Results:A total of 126 influenza cluster epidemic were reported in 115 primary and secondary schools in Beijing during 2023-2024 with the median size of 15 case, the average attack rate was 36.26% (2 033/5 607). The epidemics mainly occurred in urban area (70, 55.56%). Primary schools were the main setting (78, 61.90%), and influenza A(H3N2) was the predominant subtype (108, 85.71%). The overall influenza vaccination coverage in the primary and secondary students was 54.26%, while the average vaccination in classes affected by the epidemics was 58.57%. The overall protection rate was 47.62%, the protection rate was higher in primary schools (49.65%) than in secondary schools (46.60%). The protection rates against influenza A(H1N1)pdm09 (80.93%) and influenza B (Victoria lineage) (81.65%) were significantly higher than that against influenza A(H3N2) (44.19%). When school vaccination coverage reached ≥76.00%, the epidemic risk decreased by 52.82%.Conclusions:Even the match between influenza vaccine strains and circulating strains is suboptimal, increasing influenza vaccination coverage in schools can effectively reduce the risk for influenza cluster epidemic. In the future, measures such as policy guidance and public health education should be taken to further improve vaccination coverage, thereby establishing herd immunity and reducing the transmission risk of influenza in schools.

This study explored the effect of the Mycobacterium tuberculosis(Mtb)PE/PPE family protein PE_PGRS37 on the growth of Mycobacterium smegmatis(Ms)and macrophage autophagy during Mtb infection.The pe_pgrs37 gene was amplified from Mtb genome through PCR,and the recombinant vector pAIN-PE_PGRS37 was successfully constructed through homologous recombi-nation.pAIN-PE_PGRS37 and pAIN were integrated into Ms through electroshock to construct pAIN-PGRS37/Ms and pAIN/Ms re-combinant bacteria.Western blotting indicated that the PE_PGRS37 protein was correctly expressed in pAIN-PE_PGRS37/Ms.The re-combinant bacteria were inoculated in 7H9/7H10 medium,and their colony morphology and growth curves were observed.No signifi-cant difference in colony morphology was observed between pAIN-PE_PGRS37/Ms and pAIN/Ms.The growth rate significantly in-creased between 10 and 16 h,and a plateau was reached at 26 h.After infection of U937 cells with pAIN-PE_PGRS37/Ms and pAIN/Ms,macrophage autophagy flow was detected with western blotting and immunofluorescence.In the pAIN-PE_PGRS37/Ms-infected group,compared with the pAIN/Ms-infected group,macrophage LC3-II and p62 protein expression was significantly up-regulated(P<0.001)and inhibited autophagosome and lysosome fusion.The intracellular survival of the recombinant bacteria was detected through colony counting,and pAIN-PE_PGRS37/Ms showed significantly greater survival in macrophages at 12 h,24 h,and 48 h than pAIN/Ms(P<0.05).Our results suggested that PE_PGRS37 protein promotes Mycobacterium survival in macrophages by blocking macro-phage autophagy flow,thus inhibiting macrophage autophagy.

The objective of this study was to examine the effects of tributyrin(TB)on energy me-tabolism,oxidative stress and immune function in dairy cows with negative energy balance(NEB).In this study,25 perinatal Holstein cows from a dairy farm in Heilongjiang Province were selected.Five healthy cows were designated as the control group,and 20 cows with NEB were randomly di-vided into NEB control group,Propylene glycol(PG)group(300 mL PG),TB group(37.5 g TB)and PG+TB group(300 mL PG+37.5 g TB)with 5 cows in each group,and were continuously fed for 14 days.Blood samples were collected at 0,7,14 and 21 days.The indexes of oxidative stress,energy metabolism and immune function in the serum of dairy cows were quantified using commercially available kits.The results showed that compared with the NEB group,the contents of T-AOC,GSH-Px,CAT and SOD in the TB group were significantly increased,whereas the content of MDA was significantly decreased.These results indicated that TB can effectively alleviate the oxidative stress of cows with NEB.The contents of BHB,NEFA and BUN in the TB group were significantly decreased,indicating that TB can regulate energy metabolism disorders in cows with NEB.The contents of IL1β,IL-2,IL-6,IL-21,MIP-1 and IP-10 in the TB group were significantly decreased,while the contents of IgA,IgM and IgG were significantly increased.These results sug-gest that TB has shown significant effects in inhibiting inflammatory response and improving im-mune function.Furthermore,compared with the PG group,the contents of T-AOC,GSH-Px,CAT,SOD,IgA,IgM and IgG in the TB group and the PG+TB group were significantly in-creased,whereas the contents of MDA,BHB,NEFA,BUN,IL-1β,IL-2,IL-6,IL-21,MIP-1 and IP-10 were significantly decreased.These results indicated that feeding TB alone was effective in alle-viating oxidative stress,improving energy metabolism and inhibiting inflammation in dairy cows compared to feeding the traditional drug PG,and the effect of feeding a mixture of PG and TB was particularly significant.This study provides a new theoretical basis for the prevention and treat-ment of oxidative stress and immune function decline caused by perinatal cows with NEB.

ObjectiveTo understand the epidemic characteristics of influenza in Beijing from 2023 to 2024, and to provide a scientific basis for the prevention and control of influenza. MethodsData on influenza-like illness (ILI) from secondary level and above hospitals, etiology surveillance data, and influenza clusters outbreaks data from 2023‒2024 were used to analyze the epidemic trend and pathogenic characteristics of influenza. Furthermore, an influenza comprehensive index was used to categorize the epidemic intensity at the severity level. ResultsA total of 2 065 857 ILI cases were reported in 2023‒2024 epidemic season, and the percentage of ILI was 3.67%. The age group of 5‒14 years accounted for the highest proportion of ILI (30.48%). A total of 41 766 throat swabs from ILI were detected, with a positive rate of 17.28%.A (H3N2) (51.86%) and B Victoria (41.93%) were the most prevalent subtypes of influenza virus. Clustered influenza outbreaks occurred mainly in primary schools (57.78%) and middle schools (35.55%), mainly caused by the influenza A (H3N2) subtype (85.93%). According to the influenza comprehensive index (I), the period of influenza activity and above (I>0.5) lasted for a total of 37 weeks, accounting for 71.15% of the entire influenza season. ConclusionCompared with previous years, the epidemic level of influenza in Beijing was increased in 2023‒2024, and the peak time became earlier. The comprehensive index method can objectively evaluate the level of influenza epidemic and provide suggestions for the future prevention and control of influenza in Beijing.

ObjectiveTo investigate the therapeutic effects of direct-acting antiviral agents (DAAs) combined regimens for hepatitis C virus (HCV) patients in Dehong Prefecture, Yunnan Province from 2022 to 2024, to analyze the characteristics of treatment failure patients, so as to provide a basis for discovering more effective treatment regimens in the future. MethodsData on HCV prevention and treatment in Dehong Prefecture was extracted from the China Disease Control and Prevention Information System. A total of 617 patients with HCV antiviral therapy were included, and the differences in variable characteristics among patients with different genotypes were analyzed using comparative statistical tests, including basic socio-demographic characteristics, biochemical testing indicators, and information on previous treatment and current treatment. In addition, the cure rate of HCV patients with diverse characteristics was compared, and the potential causes of treatment failure were explored simultaneously. ResultsThe cure rate of HCV was 96.8%, and statistically significant differences were observed in aspartate transaminase (AST) and alanine transaminase (ALT) levels, previous antiviral therapy history and initial treatment regimens among patients with different HCV genotypes (all P<0.05). Among the multi-type combination regimens, the cure rate of sofosbuvir (SOF)-containing regimens was 97.00%, that of velpatasvir (VEL)-containing regimens was 95.45%, and the cure rate of other treatment regimens, including the regimens with ribavirin (RIB) intervention, was 93.10%. Among the patients with treatment failure, 45.00% had genotype 3, 40.00% had abnormal abdominal ultrasound results, and all presented with elevated baseline AST test levels. ConclusionThe clinical treatment of HCV patients should consider the differences in genotype and biochemical test results. DAAs combined regimens for HCV have achieved a high cure rate in Dehong Prefecture and are applicable to HCV patients with diverse clinical characteristics, providing research evidence for wider application.

Objective:To investigate the sero-conversion rate of HIV antibody and influencing factors in cross-border couples in Dehong Dai and Jingpo Autonomous Prefecture(Dehong).Methods:A cohort design was used to recruit HIV-negative people in cross-border couples in Dehong in 2017. Follow-up was conducted in 2023, and questionnaire survey and HIV test were carried out to calculate the sero-conversion rate of HIV antibody. Univariate and multivariate logistic regression models were used to analyze the influence factors for HIV infections.Results:A total of 36 278 HIV-negative persons in cross-border couples were included in the 2017 baseline survey, of whom 22 438 (61.9%) were tested in follow-up in 2023. The sero-conversion rate between 2017 and 2023 was 0.51% (115/22 438). Multivariate logistic regression analysis showed that length of marriage <6 years, Jingpo ethnic group, education level of primary school or below, drug use, illegal marriage and HIV infected spouse were the risk factors of HIV infection in male spouses, and length of marriage <6 years, Jingpo ethnic group, illegal marriage and HIV infected spouse were the risk factors in female spouses.Conclusions:The sero-conversion rate of HIV antibody in cross-border couples in Dehong was relatively high. HIV infection was mainly caused by secondary transmission in the couples, and men might also be infected through drug use. It is necessary to strengthen the registration and management of cross-border couples, especially the couples with discordant HIV infection status, and the intervention in drug users to reduce the risk for secondary transmission of HIV in the cross-border couples.

Objective:To analyze the effect of influenza vaccination on influenza cluster epidemic in primary and secondary schools in Beijing during the 2023-2024 surveillance season and provide evidence for the improvement of influenza vaccination strategies.Methods:The incidence data of influenza cluster epidemic and influenza vaccination coverage in the schools in Beijing during 2023-2024 were collected. Descriptive epidemiological methods were used to analyze cluster epidemic characteristics, and χ2 test was used to compare incidence differences between groups, and OR value and vaccine effectiveness [VE=(1- OR)×100%] were calculated. A negative binomial regression model was used to evaluate the association between school vaccination rates and cluster epidemic risk. Joinpoint regression was used to analyze trends in relative risk ( RR) with increasing vaccination coverage and to determine the optimal vaccination threshold. Results:A total of 126 influenza cluster epidemic were reported in 115 primary and secondary schools in Beijing during 2023-2024 with the median size of 15 case, the average attack rate was 36.26% (2 033/5 607). The epidemics mainly occurred in urban area (70, 55.56%). Primary schools were the main setting (78, 61.90%), and influenza A(H3N2) was the predominant subtype (108, 85.71%). The overall influenza vaccination coverage in the primary and secondary students was 54.26%, while the average vaccination in classes affected by the epidemics was 58.57%. The overall protection rate was 47.62%, the protection rate was higher in primary schools (49.65%) than in secondary schools (46.60%). The protection rates against influenza A(H1N1)pdm09 (80.93%) and influenza B (Victoria lineage) (81.65%) were significantly higher than that against influenza A(H3N2) (44.19%). When school vaccination coverage reached ≥76.00%, the epidemic risk decreased by 52.82%.Conclusions:Even the match between influenza vaccine strains and circulating strains is suboptimal, increasing influenza vaccination coverage in schools can effectively reduce the risk for influenza cluster epidemic. In the future, measures such as policy guidance and public health education should be taken to further improve vaccination coverage, thereby establishing herd immunity and reducing the transmission risk of influenza in schools.

Objective To investigate the interaction between a novel antimicrobial compound,HL-J6,and penicillin-binding protein 1(PBP1)of Staphylococcus aureus.Methods With MRSA252 genomic DNA as the template and PBP1F and PBP1R as primers,the expression plasmid pET30a-pbp1-39-608 was constructed by amplifying the target gene fragment followed by cloning into the Nde I/Xho I restriction sites of the pET30a vector.Then the obtained plasmids were transformed into Escherichia coli for the expression of PBP1-39-608 protein,and the product was purified by affinity chromatography.The inhibitory effect of HL-J6 on the transpeptidase activity of PBP1-39-608 was measured using peptidoglycan side chain backbone peptide,with thiol ester analog S2d as the substrate.The affinity between HL-J6 and PBP1-39-608 was detected using microscale thermophoresis(MST),and the binding interaction was confirmed by cellular thermal shift assay(CETSA).Molecular docking and dynamics simulation were performed using AutoDock Vina and Desmond software,respectively,to elucidate the binding mode of HL-J6 with the PBP1-39-608 protein and the key amino acid residues involved.Results The recombinant plasmid pET30a-pbp1-39-608 was successfully constructed,and PBP1-39-608 protein was produced after induction and purified,yielding a protein with an approximate molecular mass of 65×103.HL-J6 inhibited the transpeptidase activity of PBP1-39-608 in a time-dependent manner(P<0.001).The dissociation constant Kd of the binding between HL-J6 and PBP1-39-608 was 64.92 μmol/L.Molecular docking results showed that HL-J6 bound to the active pocket of PBP1-39-608 by interacting with key residues such as ILE-348,ASN-370,THR-516 and PHE-423,with a binding score of-8.38 kcal/mol(<-5.00 kcal/mol).Dynamics simulation results indicated that the complex became stable after 50 ns.Conclusion HL-J6 effectively inhibits the transpeptidase activity of Staphylococcus aureus PBP1,and shows stable interaction with the protein.