To investigate the expression and distribution of follicular dendritic cell(FDC)and follic-ular helper T cells(Tfh)in mouse spleen and lymph nodes induced by foot-and-mouth virus-like particles(FMDV-VLPs),the recombinant pCMV-HA-HBcAg-VP1-VP4 plasmid was transfected into CHO-K1 cells to prepare FMDV-VLPs,and the recombinant FMDV VP1-VP4 protein was expressed and purified through a prokaryotic expression system.BALB/c mice were subcutaneous-ly immunized with FMDV-VLPs(VLP group)and recombinant FMDV VP1-VP4 protein(VP1-VP4 group),and PBS control group(PBS group)was set up.At 21 d post primary immunization(dpi),booster immunization was carried out.Spleen,shoulder lymph nodes,and submandibular lymph nodes were collected at 7,28,42,72 and 102 dpi,and frozen sections were prepared.Immu-nohistochemical staining was used to observe the expression and distribution of FDC and Tfh.The results showed that the number of FDC and Tfh cells in the VLP group in the spleen and lymph nodes showed a gradual increase from 7 to 42 dpi,and gradually decreased to non-immune levels starting from 72 dpi.The results indicate that FMDV-VLPs can induce the formation of GC in the spleen and lymph nodes,and the number of FDC and Tfh cells in GC can last for at least 42 d.This study provides a theoretical basis for the study of the immune memory response mechanism of B cells induced by FMDV virus-like particles.

Objective:To compare the efficacy of posteromedial combined with lateral Frosch approach versus anterior medial and lateral dual incision approach in open reduction and internal fixation for Schatzker type VI tibial plateau fractures.Methods:A retrospective cohort study was conducted to analyze the clinical data of 41 patients with Schatzker type VI tibial plateau fractures, who were admitted to the 940th Hospital of the Joint Logistics Support Force of the PLA from January 2018 to May 2024, including 23 males and 18 females, aged 34-79 years [(50.7±7.7)years]. Twenty-three patients underwent open reduction and internal fixation via the posteromedial combined with lateral Frosch approach (posterior approach group), while 18 patients underwent the same procedure via the anterior medial and lateral dual incision approach (anterior approach group). The following parameters were compared between the two groups: operation duration, intraoperative blood loss, postoperative drainage volume, depth of articular surface depression and tibial plateau width measured preoperatively, at 7 days, 3 months postoperatively, and at the last follow-up, medial proximal tibial angle (MPTA) and posterior proximal tibial angle (PPTA) measured at 7 days, 3 months postoperatively, and at the last follow-up, visual analogue scale (VAS) scores assessed preoperatively, at 7 days postoperatively, and at the last follow-up, American Knee Society (KSS) score and knee flexion range of motion assessed at 7 days, 3 months postoperatively, and at the last follow-up, fracture healing status at the last follow-up, and incidence of postoperative complications.Results:All the patients were followed up for 12-16 months [(14.3±2.1)months]. The operation duration was (119.6±11.8)minutes in the posterior approach group, which was significantly shorter than (140.3±10.6)minutes in the anterior approach group ( P<0.05). There were no statistically significant differences in intraoperative blood loss or postoperative drainage volume between the two groups ( P>0.05). No significant differences were found in the preoperative depth of articular surface depression or tibial plateau width between the two groups ( P>0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the depth of articular surface depression was 0.8(0.6, 1.0)mm, 0.6(0.5, 0.8)mm, and 0.6(0.5, 0.7)mm in the posterior approach group, which were significantly shorter than 1.1(0.9, 1.3)mm, 0.8(0.7, 1.0)mm, and 0.8(0.7, 1.0)mm in the anterior approach group ( P<0.05). The tibial plateau width at the same time points was 71.0(69.1, 73.5)mm, 70.5(69.2, 72.9)mm, and 70.5(69.3, 72.5)mm in the posterior approach group, which were significantly shorter than 73.0(72.3, 74.2)mm, 71.5(71.0, 73.0)mm, and 71.5(71.1, 72.6)mm in the anterior approach group ( P<0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the MPTA values were (87.4±0.7)°, (87.7±0.6)°, and (87.9±0.5)° in the posterior approach group, which were significantly larger than (85.2±2.5)°, (86.0±2.2)°, and (86.3±2.0)° in the anterior approach group ( P<0.01). The PPTA values at the same time points were (9.5±0.7)°, (9.0±0.5)°, and (8.6±0.4)° in the posterior approach group, which were significantly smaller than (11.2±1.0)°, (10.3±0.8)°, and (9.8±0.7)° in the anterior approach group ( P<0.01). There was no significant difference in the preoperative VAS score between the two groups ( P>0.05). At 7 days postoperatively and at the last follow-up, the VAS scores were 4.0(3.0, 5.0)points and 0.5(0.0, 2.0)points in the posterior approach group, which were significantly lower than 5.0(4.0, 5.0)points and 1.0(1.0, 3.0)points in the anterior approach group ( P<0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the KSS scores were 62.5(57.0, 67.5)points, 75.5(72.0, 82.5)points, and 87.0(82.5, 93.5)points in the posterior approach group, which were significantly higher than 61.5(54.5, 63.0)points, 74.0(68.0, 79.0)points, and 85.5(78.0, 88.5)points in the anterior approach group ( P<0.05). The knee flexion range of motion was 90.0(85.0, 95.0)°, 115.0(109.0, 122.0)°, and 126.0(120.0, 130.0)° in the posterior approach group, which were significantly greater than 80.5(75.2, 85.8)°, 110.0(104.0, 115.0)°, and 119.0(113.0, 122.0)° in the anterior approach group ( P<0.05). At the last follow-up, all the fractures were healed in both groups. No statistically significant difference was found in the incidence of postoperative complications between the two groups ( P>0.05). Conclusion:Compared to the anterior medial and lateral dual incision approach, the posteromedial combined with lateral Frosch approach demonstrates superior advantages in operation duration, reduction quality, pain relief, functional recovery in the treatment of Schatzker type VI tibial plateau fractures, while the incidence of complications is comparable.

Objective To study the effect of wall thickness on the accuracy(trueness and precision)of 3D printed models.Methods The 3D scanning data of the standard gypsum dental arch model was imported into Exocad software.And four sets of models were de-signed,including horseshoe shaped solid model and horseshoe shaped hollow models with different wall thicknesses(2 mm,3 mm,4 mm).On the first and seventh day after printing,the 3D scanning data of resin models were imported into Geomagic software.Deviation analysis were performed on 3D printed models for the root mean square(root mean square,RMS).Results The trueness range of the four groups of printed models on the first day was(34.63±4.17)μm to(45.26±6.50)μm,there was no statistical difference.The pre-cision range was(30.25±10.18)μm to(47.65±14.77)μm,and the precision of the solid group was lower than the other three groups(P＜0.05).The trueness range of the four groups of printing models on the 7th day was(49.00±9.11)μm to(69.25±9.70)μm.The trueness of the 2 mm wall thickness group was lower than that of the solid group and the 4 mum wall thickness group(P＜0.05).Con-clusion The accuracy of printing models with different wall thicknesses was within the clinical acceptance range.There was no statisti-cally significant difference in the trueness values of the four groups of printing models on the first day.The precision value of the solid group was the lowest.On the 7th day,the trueness of the wall thickness of 2 mm group was lower than that of the solid group and the 4 mum wall thickness group.

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.

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 study the effect of wall thickness on the accuracy(trueness and precision)of 3D printed models.Methods The 3D scanning data of the standard gypsum dental arch model was imported into Exocad software.And four sets of models were de-signed,including horseshoe shaped solid model and horseshoe shaped hollow models with different wall thicknesses(2 mm,3 mm,4 mm).On the first and seventh day after printing,the 3D scanning data of resin models were imported into Geomagic software.Deviation analysis were performed on 3D printed models for the root mean square(root mean square,RMS).Results The trueness range of the four groups of printed models on the first day was(34.63±4.17)μm to(45.26±6.50)μm,there was no statistical difference.The pre-cision range was(30.25±10.18)μm to(47.65±14.77)μm,and the precision of the solid group was lower than the other three groups(P＜0.05).The trueness range of the four groups of printing models on the 7th day was(49.00±9.11)μm to(69.25±9.70)μm.The trueness of the 2 mm wall thickness group was lower than that of the solid group and the 4 mum wall thickness group(P＜0.05).Con-clusion The accuracy of printing models with different wall thicknesses was within the clinical acceptance range.There was no statisti-cally significant difference in the trueness values of the four groups of printing models on the first day.The precision value of the solid group was the lowest.On the 7th day,the trueness of the wall thickness of 2 mm group was lower than that of the solid group and the 4 mum wall thickness group.

To investigate the expression and distribution of follicular dendritic cell(FDC)and follic-ular helper T cells(Tfh)in mouse spleen and lymph nodes induced by foot-and-mouth virus-like particles(FMDV-VLPs),the recombinant pCMV-HA-HBcAg-VP1-VP4 plasmid was transfected into CHO-K1 cells to prepare FMDV-VLPs,and the recombinant FMDV VP1-VP4 protein was expressed and purified through a prokaryotic expression system.BALB/c mice were subcutaneous-ly immunized with FMDV-VLPs(VLP group)and recombinant FMDV VP1-VP4 protein(VP1-VP4 group),and PBS control group(PBS group)was set up.At 21 d post primary immunization(dpi),booster immunization was carried out.Spleen,shoulder lymph nodes,and submandibular lymph nodes were collected at 7,28,42,72 and 102 dpi,and frozen sections were prepared.Immu-nohistochemical staining was used to observe the expression and distribution of FDC and Tfh.The results showed that the number of FDC and Tfh cells in the VLP group in the spleen and lymph nodes showed a gradual increase from 7 to 42 dpi,and gradually decreased to non-immune levels starting from 72 dpi.The results indicate that FMDV-VLPs can induce the formation of GC in the spleen and lymph nodes,and the number of FDC and Tfh cells in GC can last for at least 42 d.This study provides a theoretical basis for the study of the immune memory response mechanism of B cells induced by FMDV virus-like particles.

Objective:To compare the efficacy of posteromedial combined with lateral Frosch approach versus anterior medial and lateral dual incision approach in open reduction and internal fixation for Schatzker type VI tibial plateau fractures.Methods:A retrospective cohort study was conducted to analyze the clinical data of 41 patients with Schatzker type VI tibial plateau fractures, who were admitted to the 940th Hospital of the Joint Logistics Support Force of the PLA from January 2018 to May 2024, including 23 males and 18 females, aged 34-79 years [(50.7±7.7)years]. Twenty-three patients underwent open reduction and internal fixation via the posteromedial combined with lateral Frosch approach (posterior approach group), while 18 patients underwent the same procedure via the anterior medial and lateral dual incision approach (anterior approach group). The following parameters were compared between the two groups: operation duration, intraoperative blood loss, postoperative drainage volume, depth of articular surface depression and tibial plateau width measured preoperatively, at 7 days, 3 months postoperatively, and at the last follow-up, medial proximal tibial angle (MPTA) and posterior proximal tibial angle (PPTA) measured at 7 days, 3 months postoperatively, and at the last follow-up, visual analogue scale (VAS) scores assessed preoperatively, at 7 days postoperatively, and at the last follow-up, American Knee Society (KSS) score and knee flexion range of motion assessed at 7 days, 3 months postoperatively, and at the last follow-up, fracture healing status at the last follow-up, and incidence of postoperative complications.Results:All the patients were followed up for 12-16 months [(14.3±2.1)months]. The operation duration was (119.6±11.8)minutes in the posterior approach group, which was significantly shorter than (140.3±10.6)minutes in the anterior approach group ( P<0.05). There were no statistically significant differences in intraoperative blood loss or postoperative drainage volume between the two groups ( P>0.05). No significant differences were found in the preoperative depth of articular surface depression or tibial plateau width between the two groups ( P>0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the depth of articular surface depression was 0.8(0.6, 1.0)mm, 0.6(0.5, 0.8)mm, and 0.6(0.5, 0.7)mm in the posterior approach group, which were significantly shorter than 1.1(0.9, 1.3)mm, 0.8(0.7, 1.0)mm, and 0.8(0.7, 1.0)mm in the anterior approach group ( P<0.05). The tibial plateau width at the same time points was 71.0(69.1, 73.5)mm, 70.5(69.2, 72.9)mm, and 70.5(69.3, 72.5)mm in the posterior approach group, which were significantly shorter than 73.0(72.3, 74.2)mm, 71.5(71.0, 73.0)mm, and 71.5(71.1, 72.6)mm in the anterior approach group ( P<0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the MPTA values were (87.4±0.7)°, (87.7±0.6)°, and (87.9±0.5)° in the posterior approach group, which were significantly larger than (85.2±2.5)°, (86.0±2.2)°, and (86.3±2.0)° in the anterior approach group ( P<0.01). The PPTA values at the same time points were (9.5±0.7)°, (9.0±0.5)°, and (8.6±0.4)° in the posterior approach group, which were significantly smaller than (11.2±1.0)°, (10.3±0.8)°, and (9.8±0.7)° in the anterior approach group ( P<0.01). There was no significant difference in the preoperative VAS score between the two groups ( P>0.05). At 7 days postoperatively and at the last follow-up, the VAS scores were 4.0(3.0, 5.0)points and 0.5(0.0, 2.0)points in the posterior approach group, which were significantly lower than 5.0(4.0, 5.0)points and 1.0(1.0, 3.0)points in the anterior approach group ( P<0.05). At 7 days, 3 months postoperatively, and at the last follow-up, the KSS scores were 62.5(57.0, 67.5)points, 75.5(72.0, 82.5)points, and 87.0(82.5, 93.5)points in the posterior approach group, which were significantly higher than 61.5(54.5, 63.0)points, 74.0(68.0, 79.0)points, and 85.5(78.0, 88.5)points in the anterior approach group ( P<0.05). The knee flexion range of motion was 90.0(85.0, 95.0)°, 115.0(109.0, 122.0)°, and 126.0(120.0, 130.0)° in the posterior approach group, which were significantly greater than 80.5(75.2, 85.8)°, 110.0(104.0, 115.0)°, and 119.0(113.0, 122.0)° in the anterior approach group ( P<0.05). At the last follow-up, all the fractures were healed in both groups. No statistically significant difference was found in the incidence of postoperative complications between the two groups ( P>0.05). Conclusion:Compared to the anterior medial and lateral dual incision approach, the posteromedial combined with lateral Frosch approach demonstrates superior advantages in operation duration, reduction quality, pain relief, functional recovery in the treatment of Schatzker type VI tibial plateau fractures, while the incidence of complications is comparable.

Objective To understand the molecular characteristics of Streptomycin(SM)resistance in multidrug-resistant tuberculosis(MDR-TB)in Jiangxi Province,and to explore the relationship between SM resistant genes(rpsL,rrs and gidB)mutations and SM resistant phenotypes in Beijing genotype TB.Methods 106 non-replicated MDR-TB isolates were collected from Gaoxin Branch of The First Affiliated Hospital of Nanchang University and Jiangxi Provincial Chest Hospital from January to December 2021,and tested for drug-resistance phenotypes,whether they were Beijing genotype or not and the characteristics of rpsL,rrs and gidB gene mutations.Chi-square test was performed to determine whether rpsL,rrs and gidB mutations were related to genotypes and drug-resistance phenotypes.Results Among 106 cases of MDR-TB,76 cases were resistant to SM.A total of 58 cases had rpsL 43A>G mutation,8 cases had 88A>G mutation,5 cases had rrs mutation,and 3 cases had gidB mutation.Statistical analysis showed that the coincidence rate of gene mutation and phenotypic drug-resistance detection was 89.6%,and the specificity and sensitivity were 86.7%and 90.8%,respectively.The isolated rate of Beijing genotype TB was 88.7%,and the drug-resistant gene mutations were mainly concentrated in rpsL and rrs,while the drug-resistant mutations of non-Beijing genotype were mainly concentrated in gidB;in addition,Beijing genotype bacteria were more prone to gene mutations(P = 0.013),but there was no difference in phenotypic drug-resistance.Conclusions Mutations in rpsL,rrs,and gidB genes have a good coincidence rate with phenotypic drug-resistance,and molecular biology can be used to detect directly drug-resistance genes to predict bacterial resistance;TB genotypes are strongly associated with streptomycin resistance characteristics.

Antiviral therapy is an effective means of curing chronic hepatitis C (CHC) and a key focus of preventing the spread of hepatitis C. By analyzing domestic and foreign literature, this paper provides an overview of the estimation of the antiviral treatment rate for CHC, the current situation of antiviral treatment for CHC both domestically and internationally, and the factors that affect acceptance of antiviral treatment. At present, the antiviral treatment rate for CHC cases is relatively low both domestically and internationally. The treatment status of CHC cases is related to factors such as the general situation of the case, knowing their HCV status or self-perceived condition, concurrent presence of other diseases or conditions, knowledge of hepatitis C prevention and treatment, and social interaction and behavioral guidance. In response to the relevant difficulties, in-depth research or more support is needed to improve the antiviral treatment rate of CHC cases and achieve the goal of eliminating hepatitis C by 2030. Efforts should be made to strengthen policy support, improve the diagnosis of hepatitis C, prevent and control multiple diseases together, conduct targeted publicity and education, and enhance social support.