OBJECTIVE To analyze the characteristics of global surgical site infection(SSI)outbreaks and provide references for targeted prevention and control measures.METHODS SSI outbreak events from Jan.1,1990 to Dec.31,2023 were searched from Wanfang Med,CNKI,VIP and PubMed.Data on department distribution dur-ing the outbreak,duration,investigation methods,main causes,transmission modes,pathogen composition and outbreak outcomes were summarized for analysis.RESULTS A total of 111 SSI outbreaks in 20 countries were identi-fied,involving 1 382 patients and 24 deaths.The source of the outbreak was identified in 78 cases,mainly involving med-ical personnel in 27 cases(34.62％),hospital equipment in 19 cases(24.36％),environmental factors in 11 cases(14.10％),workflow factors in 10 cases(12.82％),hospital water factors in 7 cases(8.97％)and disinfectant fac-tors in 4 cases(5.13％).The duration of SSI outbreaks abroad was 5.00(1.50,12.00)months,longer than that in China[1.00(1.00,2.00)month](P＜0.05).In China,the outbreaks mainly occurred in neurosurgery,cardiac surger-y,orthopedics,obstetrics and general surgery,while at abroad,they mainly occurred in cardiac surgery,orthopedics,and involved multiple surgical departments.Environmental hygiene methods were adopted in up to 90.63％of cases in China.Compared with China,analytical epidemiological methods and molecular epidemiological methods were more com-monly used abroad.Targeted measures and strengthened basic measures were implemented for different outbreak sources to terminate the SSI outbreaks.Pulsed-field gel electrophoresis(34 times)was a widely used molecular typing method in outbreak investigations.CONCLUSIONS Based on the analysis of SSI outbreak characteristics and risk factors,it is neces-sary to strengthen medical personnel training and monitoring of special pathogens.At the same time,the epidemiologi-cal investigation capabilities of infection control professionals should be strengthened.

OBJECTIVE To investigate the analgesic effects and potential mechanisms of the partial agonist of the 5-hydroxytryptamine 1A(5-HT1A)receptor and the selective 5-HT reuptake inhibitor,viladazone(Vil),in various animal models of pain.METHODS ① Mouse acetic acid writhing test:KM mice were divided into the model group,model+morphine 10 mg·kg-1 group,and model+Vil 2,4,8 mg·kg-1 groups.Thirty minutes after ig administration of saline(model group)or corresponding drugs,each group was ip injected with a 2%acetic acid aqueous solution(0.01 mL·g-1),and the writhing frequency of the mice was observed and recorded from 5 to 20 min.② Mouse formalin pain test:KM mice were divided into the model group and model+Vil 2,4 and 8 mg·kg-1 groups.Thirty minutes after ig adminis-tration of saline(model group)or drugs,20 μL of 5%formalin solution was sc injected into the right plantar region of the mice.The licking time(the sum of the duration of licking and biting the paw)of the mice was observed and recorded during two periods:the acute phase(0-5 min after sc formalin injec-tion)and the delayed phase(15-35 min after sc formalin injection).③ Rat chronic constriction injury(CCI)of the sciatic nerve experiment:SD rats successfully examined with a paw withdrawal threshold(PWT)<5 g were randomly divided into a CCI model group and a CCI model+Vil 2,4 and 8 mg·kg-1 group.Solvent(model group)or corresponding drugs were ig administered,and the PWT of the modeled side was measured at 30,60,120 and 240 min after the first administration to evaluate the acute anal-gesic effect of Vil on mechanical pain.Then,Vil was continuously ig administered for 14 d,and the PWT was measured 1 h after Vil administration on the 7th and 14th d to evaluate the long-term analgesic effect of Vil.Immunofluorescence staining was employed to analyze the expression levels of inflamma-tion-related proteins,ionized calcium binding adapter molecule 1(IBA-1),tumor necrosis factor α(TNF-α),and interleukin 1β(IL-1β),in brain tissues.Enzyme-linked immunosorbent assay(ELISA)was used to detect the levels of IBA-1,TNF-α and IL-1β in the dorsal root ganglion of the spinal cord in the CCI model.RESULTS ① In the mouse model of acetic acid writhing,single ig administration of morphine 10 mg·kg-1 and Vil at varied doses significantly reduced the number of writhings induced by acetic acid compared to the model group.② In the formalin-induced pain model,the average licking time of the model group was 50.5 s during the acute phase of inflammatory pain(0-5 min after intraplantar injec-tion of 5%formalin),and 347.9 s during the delayed phase of inflammatory pain(25-35 min after formalin injection).Compared to the model group,single ig administration of Vil 2-8 mg·kg-1 reduced chronic pain induced by formalin in mice,and each dose of Vil significantly decreased the licking time of mice,but had no notable impact on the licking duration exhibited by mice during acute phase.③ In the CCI model,the PWT values of CCI model rats significantly decreased compared with the control group.Pathological damage to varying extents was observed in brain slices,manifested as enlarged intercellular spaces and the appearance of vacuoles.The expression of IBA-1 in brain tissue significantly increased,while TNF-α and IL-1β hardly changed.The levels of IBA-1,TNF-α and IL-1β in the spinal dorsal root ganglion significantly increased.Compared with the CCI model,after single administration of Vil 2-8 mg·kg-1 for 60,120 and 240 min,Vil significantly reduced the PWT values.After two-week continuous administration,the PWT values in Vil 4 and 8 mg·kg-1 were significantly reduced,and Vil 2-8 mg·kg-1 could alleviate the neuropathic pain to some extent.Vil 8 mg·kg-1 significantly reduced the elevated levels of inflammatory factors compared to CCI rats.CONCLUSION The antidepressant Vil exhibits analgesic effects in mouse models of acetic acid writhing,formalin-induced inflammation,and neuropathic pain induced by CCI in rats,with a more pronounced effect on neuropathic pain.The mechanism of action may be related to the inhibition of inflammatory pathways of IBA-1.

OBJECTIVE To investigate the analgesic effects and potential mechanisms of the partial agonist of the 5-hydroxytryptamine 1A(5-HT1A)receptor and the selective 5-HT reuptake inhibitor,viladazone(Vil),in various animal models of pain.METHODS ① Mouse acetic acid writhing test:KM mice were divided into the model group,model+morphine 10 mg·kg-1 group,and model+Vil 2,4,8 mg·kg-1 groups.Thirty minutes after ig administration of saline(model group)or corresponding drugs,each group was ip injected with a 2%acetic acid aqueous solution(0.01 mL·g-1),and the writhing frequency of the mice was observed and recorded from 5 to 20 min.② Mouse formalin pain test:KM mice were divided into the model group and model+Vil 2,4 and 8 mg·kg-1 groups.Thirty minutes after ig adminis-tration of saline(model group)or drugs,20 μL of 5%formalin solution was sc injected into the right plantar region of the mice.The licking time(the sum of the duration of licking and biting the paw)of the mice was observed and recorded during two periods:the acute phase(0-5 min after sc formalin injec-tion)and the delayed phase(15-35 min after sc formalin injection).③ Rat chronic constriction injury(CCI)of the sciatic nerve experiment:SD rats successfully examined with a paw withdrawal threshold(PWT)<5 g were randomly divided into a CCI model group and a CCI model+Vil 2,4 and 8 mg·kg-1 group.Solvent(model group)or corresponding drugs were ig administered,and the PWT of the modeled side was measured at 30,60,120 and 240 min after the first administration to evaluate the acute anal-gesic effect of Vil on mechanical pain.Then,Vil was continuously ig administered for 14 d,and the PWT was measured 1 h after Vil administration on the 7th and 14th d to evaluate the long-term analgesic effect of Vil.Immunofluorescence staining was employed to analyze the expression levels of inflamma-tion-related proteins,ionized calcium binding adapter molecule 1(IBA-1),tumor necrosis factor α(TNF-α),and interleukin 1β(IL-1β),in brain tissues.Enzyme-linked immunosorbent assay(ELISA)was used to detect the levels of IBA-1,TNF-α and IL-1β in the dorsal root ganglion of the spinal cord in the CCI model.RESULTS ① In the mouse model of acetic acid writhing,single ig administration of morphine 10 mg·kg-1 and Vil at varied doses significantly reduced the number of writhings induced by acetic acid compared to the model group.② In the formalin-induced pain model,the average licking time of the model group was 50.5 s during the acute phase of inflammatory pain(0-5 min after intraplantar injec-tion of 5%formalin),and 347.9 s during the delayed phase of inflammatory pain(25-35 min after formalin injection).Compared to the model group,single ig administration of Vil 2-8 mg·kg-1 reduced chronic pain induced by formalin in mice,and each dose of Vil significantly decreased the licking time of mice,but had no notable impact on the licking duration exhibited by mice during acute phase.③ In the CCI model,the PWT values of CCI model rats significantly decreased compared with the control group.Pathological damage to varying extents was observed in brain slices,manifested as enlarged intercellular spaces and the appearance of vacuoles.The expression of IBA-1 in brain tissue significantly increased,while TNF-α and IL-1β hardly changed.The levels of IBA-1,TNF-α and IL-1β in the spinal dorsal root ganglion significantly increased.Compared with the CCI model,after single administration of Vil 2-8 mg·kg-1 for 60,120 and 240 min,Vil significantly reduced the PWT values.After two-week continuous administration,the PWT values in Vil 4 and 8 mg·kg-1 were significantly reduced,and Vil 2-8 mg·kg-1 could alleviate the neuropathic pain to some extent.Vil 8 mg·kg-1 significantly reduced the elevated levels of inflammatory factors compared to CCI rats.CONCLUSION The antidepressant Vil exhibits analgesic effects in mouse models of acetic acid writhing,formalin-induced inflammation,and neuropathic pain induced by CCI in rats,with a more pronounced effect on neuropathic pain.The mechanism of action may be related to the inhibition of inflammatory pathways of IBA-1.

Objective:New HIV infections serve as a crucial indicator for assessing the dynamic changes in the HIV epidemic. This study aims to estimate the number of new HIV infections in Dehong Dai and Jingpo Autonomous Prefecture of Yunnan Province (Dehong), using a back-calculation method that integrates diagnosis delay approaches and Bayesian theory. Additionally, it compares the differences between these two estimation methods.Methods:Data were obtained from the Chinese Information System for Disease Control and Prevention. Based on CD4 + T lymphocytes (CD4) counts depletion model, the first CD4 count prior to antiretroviral therapy of HIV-infected individuals diagnosed in Dehong from 2010 to 2023 was utilized to retroactively determine the infection date of HIV-infected individuals and ascertain the annual number of new HIV infections who had been diagnosed. Subsequently, the diagnosis delay distribution method and Bayesian theory were leveraged to assess the diagnosis probability of newly infected individuals, thereby projecting the number of new HIV infections in the region over the specified period. Results:During 2010-2023, a total of 5 693 individuals aged 15 and above, excluding mother-to-child transmission, were diagnosed with HIV in Dehong. After excluding 364 cases due to missing CD4 count results or abnormal first CD4 counts (≥2 000 cells/μl), 5 329 HIV-infected individuals were included in the final analysis. Through CD4 counts back-calculation from 2010 to 2023, the annual number of new infections diagnosed was 479, 427, 337, 305, 256, 219, 194, 193, 131, 166, 120, 71, 42 and 47. When using the diagnosis delay distribution method and life table analysis, the cumulative diagnosis probability rose from 0.301 within one year to 0.913 within 14 years, leading to a reduction in the number of estimated new infections from 577 in 2010 to 168 in 2023, with a total estimate of 4 412 (95% CI:4 350-4 480). Alternatively, based on Bayesian theory, the diagnosis probability increased from 0.413 within one year to 0.946 within 14 years, leading to a reduction in the number of estimated new infections from 557 in 2010 to 122 in 2023, with a total of 3 814 (95% CI: 3 787-3 837). Conclusions:Both methods yielded consistent results in estimating new HIV infections in Dehong from 2010 to 2023. Given the region's ongoing expansion of HIV testing, the estimates derived from Bayesian theory may more accurately reflect the actual situation. These findings provide a reference basis for formulating and optimizing HIV/AIDS prevention and control strategies in Dehong, facilitating progress toward the goal of eliminating AIDS by 2030 in the region.

Objective To verify the accuracy of γ spectrometry by analyzing the results of national interlaboratory comparisons of radionuclide analysis by γ spectrometry from 2018 to 2023. Methods A statistical analysis was conducted on the results from multiple years of participation in the national interlaboratory comparisons of radionuclide analysis by γ spectrometry. The measurement results of radionuclide specific activities in soil were analyzed to provide technical support for improving the capability to analyze radionuclides in soil. Results The laboratory participated in six interlaboratory comparisons and conducted 23 radionuclide analyses by γ spectrometry from 2018 to 2023. The relative deviation was −12.20% to 8.11%, the |Z_test| was 0 to 0.61, the U_test was 0 to 0.62, and the U_rel was 0.07 to 0.12. The overall pass rate was 100% and the excellent rate was 33.3%. In addition, 21 of the 23 (91.3%) radionuclide analyses showed full scores in experiment operation. However, the total scores were relatively low due to multiple oversights and lack of rigor in the preparation of the test reports, which prevented the laboratory from qualifying for the excellence evaluation process, resulting in a relatively low excellent rate. Conclusion The interlaboratory comparisons indicate that the measurements of radionuclides in this laboratory were all qualified, with full scores for experiment operation in several analyses. These results demonstrate that the soil radionuclide analysis system based on γ spectrometry is reliable and stable.

ObjectiveTo analyze the trend and influencing factors of low birth weight (LBW) among newborns in Chongming District of Shanghai from 2008 to 2022, so as to provide references for the development of intervention measures reducing the rate of LBW. MethodsBirth surveillance data of Chongming District of Shanghai from 2008 to 2022 were collected and organized, and the annual percentage change (APC) of LBW was calculated by using Joinpoint 5.0.2 software for trend change analysis. Logistic regression analysis was used to analyze the influencing factors of LBW. ResultsThe overall incidence of LBW was 3.71% in Chongming District, Shanghai from 2008 to 2022. Joinpoint trend analysis showed that the incidence of LBW in Chongming District had an upward trend (APC=5.49%, 95%CI: 3.31%‒7.72%, P<0.001).Multivariate logistic regression analysis showed that preterm birth, multiple births, female infants, birth defects, first pregnancy, primiparity, and a young father age (<20 years) were risk factors for LBW in Chongming District. Among the term infants, female infants, birth defects, and first pregnancy were risk factors for LBW (P<0.05). Female infants, birth defects, first pregnancy, primiparity, advanced maternal age (≥35 years), and a young father age (<20 years) were risk factors in singleton neonates. ConclusionThe incidence of LBW among newborns is on the rise in Chongming District of Shanghai. Therefore, high risk groups need to be identified, and prenatal check-ups and pregnancy care should be strengthened to reduce the risk of neonatal LBW.

Objective:To screen broadly neutralizing antibodies in human immunodeficiency virus-1（HIV-1）chronically infected individuals and characterize their molecular features and to provide new strategies for rational vaccine development and antibody-based therapeutics.Methods:A total of 34 treatment-na?ve individuals with chronic HIV-1 infection were enrolled. Plasma antibody binding levels were measured against two HIV-1 envelope proteins. Single antigen-specific memory B cells were sorted from high-binding samples，and antibody variable region genes were amplified by PCR for paired expression. The monoclonal antibodies were evaluated for neutralizing activity using pseudovirus assays，and their structural features were analyzed by integrating AlphaFold 3 prediction with Discovery Studio molecular docking.Results:Plasma samples showed strong binding to DU422-GP140 and BG505-GP140. Eight monoclonal antibodies were isolated from two donors. Among them，antibodies 0919-A4，0919-A9 and 0808-A2 could cross-react with GP140 from HIV-1 subtypes AE，BC and B. The monoclonal antibody 0919-A9 demonstrated potent neutralizing activity against SF162（Tier 1）and CH181（Tier 2）pseudoviruses，with somatic hypermutation rates of 13.27%（heavy chain）and 15.58%（light chain）. Structural modeling revealed its specific targeting of the V1V2 region on GP120.Conclusion:The isolated antibody 0919-A9 effectively neutralizes Tier 2 pseudoviruses. Its high somatic mutation frequency and V1V2-targeting property underlie its neutralizing activity，providing both a promising candidate and mechanistic insights for HIV vaccine development and antibody-based therapeutic strategies.

Objective:To screen broadly neutralizing antibodies in human immunodeficiency virus-1（HIV-1）chronically infected individuals and characterize their molecular features and to provide new strategies for rational vaccine development and antibody-based therapeutics.Methods:A total of 34 treatment-na?ve individuals with chronic HIV-1 infection were enrolled. Plasma antibody binding levels were measured against two HIV-1 envelope proteins. Single antigen-specific memory B cells were sorted from high-binding samples，and antibody variable region genes were amplified by PCR for paired expression. The monoclonal antibodies were evaluated for neutralizing activity using pseudovirus assays，and their structural features were analyzed by integrating AlphaFold 3 prediction with Discovery Studio molecular docking.Results:Plasma samples showed strong binding to DU422-GP140 and BG505-GP140. Eight monoclonal antibodies were isolated from two donors. Among them，antibodies 0919-A4，0919-A9 and 0808-A2 could cross-react with GP140 from HIV-1 subtypes AE，BC and B. The monoclonal antibody 0919-A9 demonstrated potent neutralizing activity against SF162（Tier 1）and CH181（Tier 2）pseudoviruses，with somatic hypermutation rates of 13.27%（heavy chain）and 15.58%（light chain）. Structural modeling revealed its specific targeting of the V1V2 region on GP120.Conclusion:The isolated antibody 0919-A9 effectively neutralizes Tier 2 pseudoviruses. Its high somatic mutation frequency and V1V2-targeting property underlie its neutralizing activity，providing both a promising candidate and mechanistic insights for HIV vaccine development and antibody-based therapeutic strategies.

OBJECTIVE To analyze the characteristics of global surgical site infection(SSI)outbreaks and provide references for targeted prevention and control measures.METHODS SSI outbreak events from Jan.1,1990 to Dec.31,2023 were searched from Wanfang Med,CNKI,VIP and PubMed.Data on department distribution dur-ing the outbreak,duration,investigation methods,main causes,transmission modes,pathogen composition and outbreak outcomes were summarized for analysis.RESULTS A total of 111 SSI outbreaks in 20 countries were identi-fied,involving 1 382 patients and 24 deaths.The source of the outbreak was identified in 78 cases,mainly involving med-ical personnel in 27 cases(34.62％),hospital equipment in 19 cases(24.36％),environmental factors in 11 cases(14.10％),workflow factors in 10 cases(12.82％),hospital water factors in 7 cases(8.97％)and disinfectant fac-tors in 4 cases(5.13％).The duration of SSI outbreaks abroad was 5.00(1.50,12.00)months,longer than that in China[1.00(1.00,2.00)month](P＜0.05).In China,the outbreaks mainly occurred in neurosurgery,cardiac surger-y,orthopedics,obstetrics and general surgery,while at abroad,they mainly occurred in cardiac surgery,orthopedics,and involved multiple surgical departments.Environmental hygiene methods were adopted in up to 90.63％of cases in China.Compared with China,analytical epidemiological methods and molecular epidemiological methods were more com-monly used abroad.Targeted measures and strengthened basic measures were implemented for different outbreak sources to terminate the SSI outbreaks.Pulsed-field gel electrophoresis(34 times)was a widely used molecular typing method in outbreak investigations.CONCLUSIONS Based on the analysis of SSI outbreak characteristics and risk factors,it is neces-sary to strengthen medical personnel training and monitoring of special pathogens.At the same time,the epidemiologi-cal investigation capabilities of infection control professionals should be strengthened.

Objective:New HIV infections serve as a crucial indicator for assessing the dynamic changes in the HIV epidemic. This study aims to estimate the number of new HIV infections in Dehong Dai and Jingpo Autonomous Prefecture of Yunnan Province (Dehong), using a back-calculation method that integrates diagnosis delay approaches and Bayesian theory. Additionally, it compares the differences between these two estimation methods.Methods:Data were obtained from the Chinese Information System for Disease Control and Prevention. Based on CD4 + T lymphocytes (CD4) counts depletion model, the first CD4 count prior to antiretroviral therapy of HIV-infected individuals diagnosed in Dehong from 2010 to 2023 was utilized to retroactively determine the infection date of HIV-infected individuals and ascertain the annual number of new HIV infections who had been diagnosed. Subsequently, the diagnosis delay distribution method and Bayesian theory were leveraged to assess the diagnosis probability of newly infected individuals, thereby projecting the number of new HIV infections in the region over the specified period. Results:During 2010-2023, a total of 5 693 individuals aged 15 and above, excluding mother-to-child transmission, were diagnosed with HIV in Dehong. After excluding 364 cases due to missing CD4 count results or abnormal first CD4 counts (≥2 000 cells/μl), 5 329 HIV-infected individuals were included in the final analysis. Through CD4 counts back-calculation from 2010 to 2023, the annual number of new infections diagnosed was 479, 427, 337, 305, 256, 219, 194, 193, 131, 166, 120, 71, 42 and 47. When using the diagnosis delay distribution method and life table analysis, the cumulative diagnosis probability rose from 0.301 within one year to 0.913 within 14 years, leading to a reduction in the number of estimated new infections from 577 in 2010 to 168 in 2023, with a total estimate of 4 412 (95% CI:4 350-4 480). Alternatively, based on Bayesian theory, the diagnosis probability increased from 0.413 within one year to 0.946 within 14 years, leading to a reduction in the number of estimated new infections from 557 in 2010 to 122 in 2023, with a total of 3 814 (95% CI: 3 787-3 837). Conclusions:Both methods yielded consistent results in estimating new HIV infections in Dehong from 2010 to 2023. Given the region's ongoing expansion of HIV testing, the estimates derived from Bayesian theory may more accurately reflect the actual situation. These findings provide a reference basis for formulating and optimizing HIV/AIDS prevention and control strategies in Dehong, facilitating progress toward the goal of eliminating AIDS by 2030 in the region.