Objective:To analyze the changes in the phylogenetic and antigenic characteristics of the hemagglutinin (HA) gene of influenza virus A(H3N2) [A(H3N2)] during the 2022-2024 influenza seasons in Beijing.Methods:The data of influenza-like cases and A(H3N2) strains from 17 network laboratories and their corresponding sentinel hospitals were collected during the 2022-2024 influenza seasons. The HA genes were amplified and sequenced after extracting nucleic acids of the chosen virus strains. BioEdit, the nucleotide and amino acid sequence identity were conducted, and the maximum likelihood method in MEGA 5.0 software was used to construct the phylogenetic tree of HA genes. Web Logo displayed the amino acid mutation, and the N-glycosylation sites of HA online were analyzed using the NetNGlyc1.0 Server online. The Datamonkey platform was utilized to analyze the positive selection pressure sites of the HA protein.Results:The 2022-2024 influenza season includes 2022-2023 and 2023-2024. During the influenza seasons of 2022-2024, the positive rates of A(H3N2) nucleic acid were 10.35% (2 127/20 543) and 10.47% (4 386/41 876), respectively. In the 2022-2023 influenza season, there were two peaks in the A(H3N2). The comparison of HA genes between all A(H3N2) strains studied with the 2022-2024 vaccine strain (A/Darwin/9/2021) revealed that all of the strains studied have the two amino acid mutations involving 186 and 225 receptor binding sites. There were 31 amino acid substitutions in the 2022-2023 influenza season, of which 18 variant sites involved antigenic determinants. There were 35 amino acid mutations during the 2023-2024 influenza season, of which 14 were related to antigenic determinants. There were changes in the genetic evolutionary subclades of A(H3N2) strains in two influenza seasons: from 2022 to 2023, three evolutionary subclades were co-prevalent together, with the 3C.2a1b.2a.2a.3a.1 accounting for 76.67% (23/30), the 3C.2a1b.2a.1a accounting for 20.00% (6/30), the 3C.2a1b.2a.2a.1 accounting for 3.33% (1/30); from 2023 to 2024, two subclades were prevalent, with 3C.2a1b.2a.2a.3a.1 accounting for 95.12% (39/41) and 3C.2a1b.2a.2a.1 accounting for 4.88% (2/41). The glycosylation site changes of the HA protein of A(H3N2) have been enhanced from 2023 to 2024. The 145 amino acid position of the HA protein of the A(H3N2) was the positive selection site for stress selection site analysis.Conclusions:The evolutionary subclades of the HA gene of A(H3N2) in Beijing showed changes from 2022 to 2024, and the glycosylation site polymorphism of the HA protein of A(H3N2) significantly increased from 2023 to 2024. Continuous monitoring of HA mutations in the A(H3N2) is crucial, providing a basis for developing influenza prevention and control strategies, as well as new strategic support for screening influenza vaccine components, vaccine design, and discovery of drug targets.

Objective To investigate the expression of serum microRNA-29b(miR-29b),microRNA-199a(miR-199a),and microRNA-19a-3p(miR-19a-3p)in patients with acute cerebral infarction(ACI)and their relationship with disease severity and prognosis.Methods(1)Rats were randomly divided into a control group(Control group)and a model group(Model group),with 6 rats in each group.ACI was induced in the model group using the modified Longa suture method;the expression levels of miR-29b,miR-199a,miR-19a-3p in rat serum and brain tissue were detected and analyzed.(2)A total of 106 ACI patients diagnosed at Tangshan People's Hospital from June 2023 to June 2024 were enrolled as the study group,and 108 healthy individuals who underwent physical check-ups at the same hospital during the same period were chosen as the control group.According to the NIHSS evaluation results,the study group patients were assigned into mild(42 cases),moderate(34 cases),and severe(30 cases)groups.Based on the mRS evaluation results,the patients were assigned into good prognosis(68 cases)and poor prognosis(38 cases)groups.Real-time fluorescence quantitative PCR was applied to measure the expression levels of serum miR-29b,miR-199a,and miR-19a-3p.Pearson correlation analyzed the correlation between serum miR-29b,miR-199a,miR-19a-3p levels and NIHSS score and mRS score in ACI patients.The risk factors for poor prognosis in ACI patients were analyzed using multivariate logistic regression.ROC curves were used to analyze the predictive value of serum miR-29b,miR-199a,miR-19a-3p levels and NHISS scores in poor prognosis of ACI patients.Results(1)Compared with the Control group,the levels of miR-199a and miR-19a-3p in the serum and brain tissue of the Model group rats were significantly increased,while the level of miR-29b was significantly decreased(P<0.05);(2)Compared with the control group,as the severity of ACI patients gradually increased,the levels of serum miR-199a and miR-19a-3p unusually increased in the mild,moderate,and severe groups,while the level of miR-29b was significantly decreased(P<0.05).The NHISS score,miR-199a and miR-19a-3p levels in the poor prognosis group were significantly higher than those in the good prognosis group,while miR-29b was significantly lower than that in the good prognosis group(P<0.05).The levels of serum miR-199a and miR-19a-3p were positively correlated with NIHSS score;the level of miR-29b was negatively correlated with NIHSS score(P<0.05).Elevated serum miR-199a and miR-19a-3p levels and increased NHISS score were independent risk factors for poor prognosis in ACI patients,and elevated serum miR-29b levels were protective factors for poor prognosis in ACI patients(P<0.05).The combined prediction of poor prognosis in ACI patients using serum miR-29b,miR-199a,miR-19a-3p levels and NHISS scores yielded an ACI of 0.988,which was superior to individual predictions(Z=2.878,3.551,3.300,3.452,P<0.05).Conclusion The serum expression levels of miR-199a and miR-19a-3p were significantly up-regulated,while miR-29b levels significantly down-regulated,which were related to the disease severity and prognosis.The the combination of the three miRNAs had certain value in predicting the poor prognosis of patients.MiR-29b,miR-199a,and miR-19a-3p can be used as important predictors to evaluate the progression and prognosis of ACI patients.

The phenomenon of adolescent suicide has become a serious challenge to global public health, and suicidal behavior can directly threatening the lives of adolescents.Attempted suicide during adolescence has long-term negative impacts on their health in adulthood.With the continuous development of artificial intelligence technology, machine learning has demonstrated markedly superior performance compared to traditional assessment tools in predicting the risk of suicide among adolescents.Therefore, this article reviews the application and significance of machine learning in predicting suicidal behavior among adolescents.It mainly focuses on machine learning-related concepts, the utilization of multimodal data such as text and voice, as well as the in-depth analysis of algorithmic performance.However, this learning technology continues to encounter challenges pertaining to data quality, overfitting, model interpretability as well as ethical considerations.In future practical applications, various factors, including data characteristics, problem requirements, time costs and algorithm performance, should be comprehensively considered to develop a more accurate predictive model for adolescent suicidal behavior, thereby safeguarding the mental health of adolescents.

Objective:To evaluate the efficacy and safety of the Masquelet technique on the basis of characterization of hematogenous and traumatic chronic osteomyelitis of the tibia.Methods:A retrospective analysis was conducted with chronic tibial osteomyelitis who had been treated by the Masquelet technique at Department of Orthopedic Surgery, The Fourth Medical Center, PLA General Hospital from February 2021 to June 2023. The patients were classified into 2 groups based on the underlying etiology of their conditions: a hematogenous group and a traumatic group. Treatment efficacy was evaluated in terms of infection control rate, bone graft healing time, visual analog scale (VAS) pain score, anxiety measured by the self-rating anxiety scale (SAS), and lower limb function assessed by the lower extremity functional scale (LEFS).Results:A total of 66 patients with chronic tibial osteomyelitis were included in the study. There were 17 cases in the hematogenous group. They were 11 males and 6 females with a median age of 31.0 (15.0, 45.0) years and a median disease duration of 3.0 (1.5, 8.0) months. The median interval between the first and second-stage surgeries was 11.5 (8.0, 13.0) weeks, the median volume of bone defect 25.0 (15.0, 40.0) cm 3, and the median bone graft healing time 4.0 (3.0, 4.0) months. No bacteria were detected in secretion culture in 6 cases and Staphylococcus aureus was found in 6 cases. At 12 months postoperatively, the median VAS score was 1.0 (0.0, 2.0) point, the median SAS score 27.0 (20.0, 32.0) points, and the median LEFS score 78.0 (75.0, 80.0) points. There were 49 cases in the traumatic group. They were 36 males and 13 females with a median age of 52.0 (42.0, 63.0) years and a median disease duration of 6.0 (3.0, 36.0) months. The median interval between the first and second-stage surgeries was 10.0 (8.0, 17.0) weeks, the median volume of bone defect 30.0 (22.0, 53.0) cm 3, and the median bone graft healing time 3.5 (3.0, 4.5) months. No bacteria were detected in secretion culture in 10 cases and Staphylococcus aureus was found in 19 cases. At 12 months postoperatively, the median VAS score was 2.0 (1.0, 3.0) points, the median SAS score 35.0 (28.0, 42.0) points, and the median LEFS score 54.0 (42.0, 60.0) points. According to the McKee criteria for infection treatment, 14 cases achieved complete recovery, 2 ones showed improvement, and 1 case experienced recurrence in the hematogenous group, while 44 cases achieved complete recovery, 4 ones showed improvement, and 1 case experienced recurrence in the traumatic group. Conclusions:Although hematogenous and traumatic cases of chronic osteomyelitis of the tibia differ in terms of age of onset, disease duration, and lesion extent, Staphylococcus aureus is the predominant pathogen in both conditions. Application of the Masquelet technique has proven to be an effective treatment for both conditions with comparable bone graft healing time.

Objective:To analyze the changes in the phylogenetic and antigenic characteristics of the hemagglutinin (HA) gene of influenza virus A(H3N2) [A(H3N2)] during the 2022-2024 influenza seasons in Beijing.Methods:The data of influenza-like cases and A(H3N2) strains from 17 network laboratories and their corresponding sentinel hospitals were collected during the 2022-2024 influenza seasons. The HA genes were amplified and sequenced after extracting nucleic acids of the chosen virus strains. BioEdit, the nucleotide and amino acid sequence identity were conducted, and the maximum likelihood method in MEGA 5.0 software was used to construct the phylogenetic tree of HA genes. Web Logo displayed the amino acid mutation, and the N-glycosylation sites of HA online were analyzed using the NetNGlyc1.0 Server online. The Datamonkey platform was utilized to analyze the positive selection pressure sites of the HA protein.Results:The 2022-2024 influenza season includes 2022-2023 and 2023-2024. During the influenza seasons of 2022-2024, the positive rates of A(H3N2) nucleic acid were 10.35% (2 127/20 543) and 10.47% (4 386/41 876), respectively. In the 2022-2023 influenza season, there were two peaks in the A(H3N2). The comparison of HA genes between all A(H3N2) strains studied with the 2022-2024 vaccine strain (A/Darwin/9/2021) revealed that all of the strains studied have the two amino acid mutations involving 186 and 225 receptor binding sites. There were 31 amino acid substitutions in the 2022-2023 influenza season, of which 18 variant sites involved antigenic determinants. There were 35 amino acid mutations during the 2023-2024 influenza season, of which 14 were related to antigenic determinants. There were changes in the genetic evolutionary subclades of A(H3N2) strains in two influenza seasons: from 2022 to 2023, three evolutionary subclades were co-prevalent together, with the 3C.2a1b.2a.2a.3a.1 accounting for 76.67% (23/30), the 3C.2a1b.2a.1a accounting for 20.00% (6/30), the 3C.2a1b.2a.2a.1 accounting for 3.33% (1/30); from 2023 to 2024, two subclades were prevalent, with 3C.2a1b.2a.2a.3a.1 accounting for 95.12% (39/41) and 3C.2a1b.2a.2a.1 accounting for 4.88% (2/41). The glycosylation site changes of the HA protein of A(H3N2) have been enhanced from 2023 to 2024. The 145 amino acid position of the HA protein of the A(H3N2) was the positive selection site for stress selection site analysis.Conclusions:The evolutionary subclades of the HA gene of A(H3N2) in Beijing showed changes from 2022 to 2024, and the glycosylation site polymorphism of the HA protein of A(H3N2) significantly increased from 2023 to 2024. Continuous monitoring of HA mutations in the A(H3N2) is crucial, providing a basis for developing influenza prevention and control strategies, as well as new strategic support for screening influenza vaccine components, vaccine design, and discovery of drug targets.

The phenomenon of adolescent suicide has become a serious challenge to global public health, and suicidal behavior can directly threatening the lives of adolescents.Attempted suicide during adolescence has long-term negative impacts on their health in adulthood.With the continuous development of artificial intelligence technology, machine learning has demonstrated markedly superior performance compared to traditional assessment tools in predicting the risk of suicide among adolescents.Therefore, this article reviews the application and significance of machine learning in predicting suicidal behavior among adolescents.It mainly focuses on machine learning-related concepts, the utilization of multimodal data such as text and voice, as well as the in-depth analysis of algorithmic performance.However, this learning technology continues to encounter challenges pertaining to data quality, overfitting, model interpretability as well as ethical considerations.In future practical applications, various factors, including data characteristics, problem requirements, time costs and algorithm performance, should be comprehensively considered to develop a more accurate predictive model for adolescent suicidal behavior, thereby safeguarding the mental health of adolescents.

Objective:To evaluate the efficacy and safety of the Masquelet technique on the basis of characterization of hematogenous and traumatic chronic osteomyelitis of the tibia.Methods:A retrospective analysis was conducted with chronic tibial osteomyelitis who had been treated by the Masquelet technique at Department of Orthopedic Surgery, The Fourth Medical Center, PLA General Hospital from February 2021 to June 2023. The patients were classified into 2 groups based on the underlying etiology of their conditions: a hematogenous group and a traumatic group. Treatment efficacy was evaluated in terms of infection control rate, bone graft healing time, visual analog scale (VAS) pain score, anxiety measured by the self-rating anxiety scale (SAS), and lower limb function assessed by the lower extremity functional scale (LEFS).Results:A total of 66 patients with chronic tibial osteomyelitis were included in the study. There were 17 cases in the hematogenous group. They were 11 males and 6 females with a median age of 31.0 (15.0, 45.0) years and a median disease duration of 3.0 (1.5, 8.0) months. The median interval between the first and second-stage surgeries was 11.5 (8.0, 13.0) weeks, the median volume of bone defect 25.0 (15.0, 40.0) cm 3, and the median bone graft healing time 4.0 (3.0, 4.0) months. No bacteria were detected in secretion culture in 6 cases and Staphylococcus aureus was found in 6 cases. At 12 months postoperatively, the median VAS score was 1.0 (0.0, 2.0) point, the median SAS score 27.0 (20.0, 32.0) points, and the median LEFS score 78.0 (75.0, 80.0) points. There were 49 cases in the traumatic group. They were 36 males and 13 females with a median age of 52.0 (42.0, 63.0) years and a median disease duration of 6.0 (3.0, 36.0) months. The median interval between the first and second-stage surgeries was 10.0 (8.0, 17.0) weeks, the median volume of bone defect 30.0 (22.0, 53.0) cm 3, and the median bone graft healing time 3.5 (3.0, 4.5) months. No bacteria were detected in secretion culture in 10 cases and Staphylococcus aureus was found in 19 cases. At 12 months postoperatively, the median VAS score was 2.0 (1.0, 3.0) points, the median SAS score 35.0 (28.0, 42.0) points, and the median LEFS score 54.0 (42.0, 60.0) points. According to the McKee criteria for infection treatment, 14 cases achieved complete recovery, 2 ones showed improvement, and 1 case experienced recurrence in the hematogenous group, while 44 cases achieved complete recovery, 4 ones showed improvement, and 1 case experienced recurrence in the traumatic group. Conclusions:Although hematogenous and traumatic cases of chronic osteomyelitis of the tibia differ in terms of age of onset, disease duration, and lesion extent, Staphylococcus aureus is the predominant pathogen in both conditions. Application of the Masquelet technique has proven to be an effective treatment for both conditions with comparable bone graft healing time.

Objective:To analyze the external quality control assessment results of fluoride testing laboratories in endemic disease prevention and control institutions nationwide from 2006 to 2023, investigate the quality control capabilities of these laboratories in various provinces, prefectures, cities, and counties nationwide, and ensure the accuracy and reliability of surveillance data on endemic fluorosis nationwide.Methods:Using retrospective analysis, the external quality control assessment results of all participating fluoride testing laboratories of national endemic disease prevention and control institutions from 2006 to 2023 were summarized and analyzed. The assessment results from 2006 to 2008 were tested for outliers using Grubbs method, homogeneity of variance using Cochran method, excluding the assessment data of unqualified laboratories, calculating the total mean and total standard deviation, Z-score method was used to test the assessment of laboratories, and statistical analysis and judgment were done when the result of │Z│ < 3. The assessment results from 2009 - 2023 were obtained from all laboratories. In 2010, two tests were conducted in the first and second half of the year, and the Z-ratio scores of each laboratory were calculated using robust statistics. When │Z│≤2, the assessment was qualified; when 2 < │Z│ < 3, the assessment was basically qualified; when│Z│≥3, the assessment was unqualified, and the consensus value came from all participating laboratories in the assessment.Results:From the beginning of quality control operation in 2006 to 2023, the number of laboratories participated in external quality control assessments had significantly increased. The number of laboratories participated in water fluoride assessment increased from 30 in 2006 to 1 277 in 2023, and the number of laboratories participated in urine fluoride assessment increased from 29 to 497. The number of laboratories participated in the brick tea fluorine assessment had increased from 43 in 2014 to 193 in 2023. The assessment results showed that when │Z│ < 3, the total qualified rate of fluoride external quality control in fluoride testing laboratories of national endemic disease control institutions was 95.2%, with the lowest being 87.1% (27/31) in 2008 and the highest being 100.0% (394/394) in 2014. When │Z│≤2, the total feedback pass rate was 88.4%, with the lowest being 79.3% (288/363) in the first half of 2010 and the highest being 99.5% (392/394) in 2014. The assessment results showed that when │Z│ < 3, the total pass rate of urine fluoride external quality control in fluoride testing laboratories of national endemic disease control institutions was 98.0%, with the lowest being 86.2% (25/29) in 2006 and 2007, respectively, and the highest being 100.0% (68/68) in 2014. When │Z│≤2, the total qualification rate was 93.7%, with the lowest being 86.5% (64/74) in the second half of 2010 and the highest being 100.0% (68/68) in 2014. The assessment results showed that when│Z│ < 3, the total pass rate of extra-fluoride quality control of brick tea in fluoride testing laboratories of national endemic disease control institutions was 95.4%, with the lowest being 85.0% (164/193) in 2023, and the highest being 100.0% (43/43, 51/51, 79/79) in 2014, 2015 and 2016, respectively. When │Z│≤2, the total pass rate was 89.2%, with the lowest being 72.7% (32/44) in 2017 and the highest being 100.0% (43/43) in 2014. From 2009 to 2023, there were a total of 21 provincial-level laboratories that passed the water fluoride detection assessment, including 3 provinces where all prefecture level and county-level laboratories were qualified. The assessment results of urinary fluorine showed that there were 11 qualified provincial-level laboratories and 1 prefecture-level laboratory. From 2014 to 2023, the assessment results of brick-tea fluorine showed that there were 5 provincial-level laboratories that passed the tea fluorine testing assessment and no prefecture-level laboratory.Conclusions:Conclusion: From 2006 to 2023, the number of fluoride testing laboratories participating in external quality control assessment has increased year by year, and most provincial, municipal and county-level laboratories have good fluoride testing capabilities, which can meet the testing needs of endemic disease prevention and monitoring. For some laboratories with problems, targeted rectification should be carried out to improve the quality of detection, in order to provide better technical support for the monitoring of endemic fluorosis areas.

Objective    To predict the probability of lymph node metastasis after thoracoscopic surgery in patients with lung adenocarcinoma based on nomogram. Methods    We analyzed the clinical data of the patients with lung adenocarcinoma treated in the department of thoracic surgery of our hospital from June 2018 to May 2021. The patients were randomly divided into a training group and a validation group. The variables that may affect the lymph node metastasis of lung adenocarcinoma were screened out by univariate logistic regression, and then the clinical prediction model was constructed by multivariate logistic regression. The nomogram was used to show the model visually, the receiver operating characteristic (ROC) curve, calibration curve and clinical decision curve to evaluate the calibration degree and practicability of the model. Results    Finally 249 patients were collected, including 117 males aged 53.15±13.95 years and 132 females aged 47.36±13.10 years. There were 180 patients in the training group, and 69 patients in the validation group. There was a significant correlation between the 6 clinicopathological characteristics and lymph node metastasis of lung adenocarcinoma in the univariate logistic regression. The area under the ROC curve in the training group was 0.863, suggesting the ability to distinguish lymph node metastasis, which was confirmed in the validation group (area under the ROC curve was 0.847). The nomogram and clinical decision curve also performed well in the follow-up analysis, which proved its potential clinical value. Conclusion    This study provides a nomogram combined with clinicopathological characteristics, which can be used to predict the risk of lymph node metastasis in patients with lung adenocarcinoma with a diameter≤3 cm.

Objective: To analyze the epidemiological and molecular characteristics of norovirus outbreaks in schools in Xicheng District of Beijing from 2017 to 2022, so as to provide evidence for the prevention and control of norovirus outbreaks in schools. Methods: Data of norovirus outbreaks in schools in Xicheng District, Beijing during 2017 to 2022 were collected and analyzed by descriptive epidemiological methods. Realtime PCR was used to detect the nucleic acid of group GⅠand GⅡnorovirus, the positive norovirus nucleic acid samples were sent to Beijing Center for Disease Control and Prevention for molecular typing. Results: From 2017 to 2022, 185 norovirus outbreaks were reported in schools in Xicheng District, including 166 cluster outbreaks and 19 outbreaks. A total of 2 044 cases were reported, with a total attack rate of 13.92%. There were two peaks in the outbreak time, which were from March to June after the spring semester and from October to December after autumn semester. Primary schools were the most common place of occurrence (101 cases), followed by nursery institutions (68 cases) and secondary schools (16 cases). There were statistically significant differences in the incidence rates among different sites(12.37%, 22.78%, 8.47%, χ2=263.34, P<0.01). There were significant differences in the incidence of vomiting, diarrhea, nausea and stomachache among different students (χ2=263.33, 90.58, 20.42, 30.29, P<0.01). Vomiting was the main symptom in primary school and nursery school children (96.41%, 98.28%), and the diarrhea rate was higher in middle school students (68.22%). The outbreaks were mainly caused by type GⅡ norovirus. The genotype from 2017 to 2021 showed the characteristics of diversity, mainly GⅡ.2[P16], but there was no significant advantage for the GⅡ.2 [P16] during 2019 to 2021. Conclusions The norovirus outbreak in schools in Xicheng district of Beijing from 2017 to 2022 are mainly caused by GⅡ type genome. The main genotype is GⅡ.2[P16]. Norovirus infection mainly occurred in primary schools and kindergartens. For the vulnerable populations, it is necessary to improve the capacity to early identification, student infectious disease management, active infection control and prevention measures, and pathogen surveillance and sporadic case monitoring.