BACKGROUND:Early exercise treatment is the main prevention way for traumatic joint contracture and is also a research focus.Swimming may be a potential intervention for joint contracture due to the special physical properties of water. OBJECTIVE:To explore the effects of swimming on the development of joint contracture in a rat model and study its mechanisms. METHODS:Twenty-four Sprague-Dawley rats were randomly divided into a blank control group(n=8)and a joint contracture group(n=16).After the surgical operation of knee joint contracture rat models,the joint contracture group was randomly subdivided into a surgical control group(n=8)and a swimming treatment group(n=8).Swimming started in the swimming treatment group in the second week after surgery and lasted for a total of 5 weeks.At the 6th week after surgery,the body mass,knee joint range of motion,and quadriceps diameter were tested,and the diameter/body mass index was calculated.Hematoxylin-eosin staining was performed to detect the pathological changes in the knee joint capsule and quadriceps muscle,and Masson staining was used to observe fibrotic changes in the knee joint capsule.Furthermore,the protein expression of transforming growth factor β1 and type I collagen in the knee joint capsule was quantified by immunohistochemical assay and western blot was performed to detect the protein expression of MuRF1 in the quadriceps femoris. RESULTS AND CONCLUSION:Compared with the blank control group,the knee range of motion decreased in the surgical control and swimming treatment groups(P<0.01),and knee extension deficit and arthrogenic extension deficit were significantly increased(P<0.01),the diameter of the quadriceps muscle was decreased(P<0.01),the joint capsule showed significant fibrosis,the quadriceps muscle was atrophied,and the diameter/body mass index was decreased(P<0.01).Compared with the surgical control group,the swimming treatment group showed a significant increase in knee joint range of motion and quadriceps diameter(P<0.01),and significant improvement in joint capsule fibrosis and quadriceps atrophy.Compared with the blank control group,collagen fiber content and expression of transforming growth factor β1 and type I collagen were increased in the joint capsule of rats in both the surgical control group and the swimming treatment group(P<0.01).Compared with the surgical control group,collagen fiber content and expression of transforming growth factor β1 and type I collagen protein in the joint capsule were decreased in the swimming treatment group.Compared with the blank control group,the expression of MuRF1 protein in the quadriceps muscle of rats in the surgical control group and the swimming treatment group was increased(P<0.05).Compared with the surgical control group,the expression of MuRF1 protein in the quadriceps muscle of rats in the swimming treatment group was decreased(P<0.05).To conclude,early swimming intervention reduces transforming growth factor β1 and type I collagen expression in the joint capsule of traumatic joint contracture rats,decreases MuRF1 expression in the quadriceps muscle,and increases joint range of motion and quadriceps diameter,thereby inhibiting the development of joint contracture.

Purpose To evaluate the value of preoperative MRI-based radiomic models for assessing tumor-infiltrating CD8+T-cell expression in glioblastoma patients,and to identify the most stable and efficient radiomic feature region for predicting prognosis following immunotherapy.Materials and Methods This retrospective study included 150 patients with histopathologically confirmed glioblastoma from Lanzhou University Second Hospital(January 2018 to April 2022).Tumor-infiltrating CD8+T-cell expression was quantitatively assessed using immunohistochemical staining,with patients stratified into CD8-high and CD8-low expression groups based on overall survival.A total of 1 185 radiomic features were extracted from each patient's contrast-enhanced T1C and T2WI images,covering the original tumor region and sequentially expanded peritumoral regions(2.5 mm,5.0 mm,7.5 mm,10.0 mm,12.5 mm,15.0 mm morphological dilation of tumor core+peritumoral area).Feature selection was performed using variance threshold,minimum redundancy maximum relevance,and least absolute shrinkage and selection operator methods.XGBoost classifier was employed to construct clinical,radiomic,and clinical-radiomic multimodal combined prediction models.Diagnostic performance was evaluated using receiver operating characteristic curve analysis.Results The radiomic model based on tumor expansion of 7.5 mm(tumor+peritumoral region)demonstrated optimal predictive performance.The clinical-radiomic multimodal combined model showed superior predictive capability compared to clinical and radiomic models alone,achieving an area under the curve of 0.991 and accuracy of 99.0%in the training set,and area under the curve of 0.840 with accuracy of 80.0%in the validation set.Conclusion MRI radiomics provides a feasible approach for evaluating tumor-infiltrating CD8+T-cell expression in glioblastoma patients,offering potential for preoperative prognosis prediction.

Objective To enhance the mechanical properties of trichiral honeycomb sandwich structures and satisfy the design criteria for vertebral implant structures.Methods A chiral-like honeycomb sandwich structure with an auxiliary support structure was constructed for optimal design.The finite element method was used to study the influence of the auxiliary support structure on the chiral-like honeycomb sandwich structure and the relationship between the support position and mechanical property parameters.Furthermore,the influence of the deformation mechanism of different structures on mechanical properties was discussed.Results All chiral-like honeycomb sandwich structures exhibited enhanced mechanical properties in comparison to trichiral honeycomb sandwich structures.The mechanical properties of the chiral-like dCW honeycomb sandwich structure with the auxiliary support structure positioned perpendicular to the ligament were optimal,and this position represented the optimal support position.When the volume was used as a control variable,the compressive stiffness,stiffness-to-mass ratio,and transverse strain of the chiral-like honeycomb sandwich structure in the x1 direction were significantly correlated with the change of the support position,and all of them were positively correlated.Conclusions As a novel chiral-like honeycomb structure,it provides a biomechanical basis for the optimal design and clinical application of honeycomb sandwich structures as vertebral implant structures.

Objective:To investigate the relationship between oxygen consumption (VO 2), carbon dioxide production (VCO 2), and Oxygen Consumption/lactate (VO 2/Lac) with risk of death in patients with severe ARDS. Methods:A retrospective cohort study method was used, and the study subjects were hospitalized for >5 days adult patients with severe ARDS in the central intensive care unit of Henan Provincial People's Hospital from 1 March 2020 to 30 June 2023. The following patients were excluded: IC test was not completed on the 4th day of ICU admission, IC test results were unreliable, mechanical ventilation duration had exceeded 48 h at the time of ICU transfer or admission, palliative care patients and pregnant and parturient women. Using indirect calorimetry to determine VO 2 and VCO 2 values on the 4th day of admission, reviewing medical records to obtain general condition, disease information, blood gas analysis (including lactate value), diagnostic and therapeutic measures, and following up deaths by telephone and time of death. The primary outcome measure was death at 90 days, and the secondary outcome measure was death at 28 days, length of stay in ICU, total length of stay, and total hospitalization cost. Cox regression analysis and linear regression analysis were used to investigate the relationship between VO 2, VCO 2, VO 2/Lac and primary and secondary outcome indexes. Results:A total of 216 patients were enrolled, 78 patients (36.1%) died and 138 patients (63.9%) survived at 90 days. After correction for confounders, the results of multifactorial Cox regression analysis suggested that compared with the Q4 group, HR (95% CI) for 90-day risk of death in the VO 2 Q1 and Q2 groups was 3.21 (1.38, 7.49) and 3.24 (1.42, 7.38), and HR (95% CI) for 90-day risk of death in the VCO 2 Q1, Q2 and Q3 groups was 5.88 (2.33, 14.84), 4.26 (1. 60, 11.34) and 3.54 (1.34, 9.35), respectively, and the HR (95% CI) for 90-day risk of death in the VO 2/Lac Q1, Q2 and Q3 groups were 8.72 (3.01, 25.25), 8.43 (2.91, 24.47) and 4.04 (1.34, 12.17) respectively. P-trends were all <0.05, indicating that VO 2, VCO 2 and VO 2/Lac were linearly and negatively associated with the risk of 90-day mortality. In addition, VO 2, VCO 2, and VO 2/Lac were negatively associated with 28-day risk of death and higher VO 2/Lac was negatively associated with length of ICU stay. Conclusions:VO 2, VCO 2 and VO 2/Lac were negatively associated with 90-day mortality risk and 28-day mortality risk in patients with severe ARDS and may be independent risk factors predicting mortality risk of such patients.

Purpose To evaluate the value of preoperative MRI-based radiomic models for assessing tumor-infiltrating CD8+T-cell expression in glioblastoma patients,and to identify the most stable and efficient radiomic feature region for predicting prognosis following immunotherapy.Materials and Methods This retrospective study included 150 patients with histopathologically confirmed glioblastoma from Lanzhou University Second Hospital(January 2018 to April 2022).Tumor-infiltrating CD8+T-cell expression was quantitatively assessed using immunohistochemical staining,with patients stratified into CD8-high and CD8-low expression groups based on overall survival.A total of 1 185 radiomic features were extracted from each patient's contrast-enhanced T1C and T2WI images,covering the original tumor region and sequentially expanded peritumoral regions(2.5 mm,5.0 mm,7.5 mm,10.0 mm,12.5 mm,15.0 mm morphological dilation of tumor core+peritumoral area).Feature selection was performed using variance threshold,minimum redundancy maximum relevance,and least absolute shrinkage and selection operator methods.XGBoost classifier was employed to construct clinical,radiomic,and clinical-radiomic multimodal combined prediction models.Diagnostic performance was evaluated using receiver operating characteristic curve analysis.Results The radiomic model based on tumor expansion of 7.5 mm(tumor+peritumoral region)demonstrated optimal predictive performance.The clinical-radiomic multimodal combined model showed superior predictive capability compared to clinical and radiomic models alone,achieving an area under the curve of 0.991 and accuracy of 99.0%in the training set,and area under the curve of 0.840 with accuracy of 80.0%in the validation set.Conclusion MRI radiomics provides a feasible approach for evaluating tumor-infiltrating CD8+T-cell expression in glioblastoma patients,offering potential for preoperative prognosis prediction.

Objective To enhance the mechanical properties of trichiral honeycomb sandwich structures and satisfy the design criteria for vertebral implant structures.Methods A chiral-like honeycomb sandwich structure with an auxiliary support structure was constructed for optimal design.The finite element method was used to study the influence of the auxiliary support structure on the chiral-like honeycomb sandwich structure and the relationship between the support position and mechanical property parameters.Furthermore,the influence of the deformation mechanism of different structures on mechanical properties was discussed.Results All chiral-like honeycomb sandwich structures exhibited enhanced mechanical properties in comparison to trichiral honeycomb sandwich structures.The mechanical properties of the chiral-like dCW honeycomb sandwich structure with the auxiliary support structure positioned perpendicular to the ligament were optimal,and this position represented the optimal support position.When the volume was used as a control variable,the compressive stiffness,stiffness-to-mass ratio,and transverse strain of the chiral-like honeycomb sandwich structure in the x1 direction were significantly correlated with the change of the support position,and all of them were positively correlated.Conclusions As a novel chiral-like honeycomb structure,it provides a biomechanical basis for the optimal design and clinical application of honeycomb sandwich structures as vertebral implant structures.

Objective:To explore the pattern of lymph node metastasis and prognosis in locally advanced gastric cancer after neoadjuvant immunotherapy combined with chemotherapy (NICT).Methods:This retrospective study included pathologically confirmed gastric adenocarcinoma (cT3-4aN+) patients who underwent radical resection after ≥2 cycles of PD-1 inhibitor-based chemotherapy with complete postoperative pathology. Exclusions: distant/other metastases, non-R0 resection, Her-2+ with targeted therapy, microsatellite instability, or esophagogastric junction cancer invading >1 cm into lower esophagus. From January 2020 to December 2024, a total of 343 consecutive gastric cancer patients who received NICT treatment were admitted to Tianjin Medical University Cancer Institute and Hospital. According to the above criteria, 324 cases were included in the lymph node metastasis analysis, and 302 cases were included in the survival analysis. The median age of all patients was 58 years, with 245 males (75.6%) and a median body mass index (BMI) of 22.9 kg/m2. There were 170 cases (52.5%) at T3 stage and 154 cases (47.5%) at T4a stage; the median number of cycles of neoadjuvant immunotherapy combined with chemotherapy was 3 cycles. The primary outcome measure was the positive lymph node metastasis rate (number of metastatic cases in the group / total number of dissected cases in the group×100%). A positive lymph node metastasis rate >10% was defined as high metastasis, and <5% as low metastasis. The secondary outcome measures were high-risk factors for lymph node metastasis and influencing factors related to patient prognosis. Lymph node grouping was performed according to the 8th edition of the American Joint Committee on Cancer (AJCC) guidelines. The positive lymph node metastasis rate was statistically analyzed by stratification based on surgical methods (total gastrectomy, proximal gastrectomy, distal gastrectomy). Multivariate analysis of risk factors for lymph node metastasis were performed with logistic regression analysis, and survival analysis were performed with the Kaplan-Meier method and Cox regression model.Results:The postoperative pathological complete response rate (pCR) of all patients was 21.0% (68/324), and the overall positive lymph node metastasis rate was 48.8% (158/324). A total of 150 patients underwent total gastrectomy, 42 underwent proximal gastrectomy, and 132 underwent distal gastrectomy.In the total gastrectomy group: the high metastasis subgroups were No.1 (19.3%, 29 cases), No.2 (14.7%, 22 cases), No.3 (28.0%, 42 cases), No.7 (12.7%, 19 cases), No.8a (16.0%, 24 cases), and No.9 (17.3%, 26 cases); the low metastasis subgroups were No.5 (4.7%, 7 cases), No.10 (3.3%, 5 cases), No.11d (1.3%, 2 cases), and No.12a (4.0%, 6 cases).In the proximal gastrectomy group: the high metastasis subgroups were No.3 (14.3%, 6 cases), No.7 (23.8%, 10 cases), and No.11p (11.9%, 5 cases); the low metastasis subgroups were No.4d (2.4%, 1 case) and No.10 (2.4%, 1 case).In the distal gastrectomy group: the high metastasis subgroups were No.3 (25.8%, 34 cases), No.6 (26.5%, 35 cases), No.7 (11.4%, 15 cases), and No.11p (11.4%, 15 cases); the low metastasis subgroups were No.4sb (3.8%, 5 cases) and No.12a (4.5%, 6 cases).Results of multivariate analysis showed that TRG grade (HR: 5.938, 95%CI: 3.028-11.646, P<0.001) was an independent factor affecting lymph node metastasis in patients with locally advanced gastric cancer after neoadjuvant immunotherapy combined with chemotherapy. The median follow-up time was 26.0 (6.0-54.3) months, and the 3-year overall survival (OS) of all patients was 78.1%. Results of multivariate Cox analysis showed that ypT (HR=1.744, 95%CI: 1.300-2.338, P<0.001), ypN (HR=1.998, 95%CI: 1.503-2.655, P<0.001), and postoperative complications (HR=1.913, 95%CI: 1.111-3.294, P=0.019) were independent factors affecting the overall survival of patients with locally advanced gastric cancer after neoadjuvant immunotherapy combined with chemotherapy. Conclusion:NICT significantly changes the pattern of lymph node metastasis in LAGC. ypT and ypN stages are core indicators for survival prognosis. The necessity of dissection for lymph node groups with a metastasis rate <5% needs to be carefully evaluated.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

Objective:To compare the impact of different treatment strategies on the survival outcomes in rectal cancer patients with poor response to neoadjuvant therapy, and to explore the survival-related influencing factors.Methods:A retrospective cohort study was conducted. Between January 2018 and November 2022, the clinical, pathological, and follow-up data of 106 rectal cancer patients who received neoadjuvant therapy and were evaluated as grade 4 or 5 based on the Magnetic Resonance Tumor Regression Grade (mrTRG) from the rectal cancer database at Peking Union Medical College Hospital were retrospectively collected. Based on the post-neoadjuvant therapy assessment, patients were classified into three groups: the chemotherapy-radiotherapy group (23 patients), the consolidation therapy group (18 patients), and the standard treatment group (65 patients). General condition, pathological findings, selection of neoadjuvant therapy, comorbidities, as well as 3-year expected DMFS and OS were observed in the three groups.Results:All 106 patients were followed up, with a median follow-up time of 28 (21, 38) months. The overall 3-year DMFS rate was 60%, and the 3-year OS rate was 74%. The 3-year DMFS in the standard treatment and consolidation therapy groups were 74% and 72%, respectively; the 3-year OS were 84%, 81%, respectively. The Log-rank test showed that there was no significant difference in the 3-year expected DMFS and OS between the standard treatment group and the consolidation therapy group (both P>0.05), but both groups had better survival outcomes than the chemotherapy-radiotherapy group (10% and 39%, respectively; all P<0.001). Multivariate Cox regression analysis indicated that the chemotherapy-radiotherapy only regimen was an independent risk factor for DMFS (HR=12.425, 95% CI: 4.436–34.594, P<0.001), and the independent risk factors for OS were chemotherapy-radiotherapy only regimen (HR=8.991, 95%CI:2.220–36.403, P=0.002) and age≥65 years (HR=3.495, 95%CI: 1.017–12.009, P=0.047). Stratified analysis showed that chemotherapy-radiotherapy only regimen was the independent risk factors for DMFS and OS in patients with extramural vascular invasion (EMVI) positive ( n=66) and mesorectal fascial invasion (MRF) positive (n=56) (all P<0.05). Whether consolidation therapy was added to the standard neoadjuvant treatment regimen was not an independent factor affecting 3-year expected DMFS or OS in rectal cancer patients with poor response to neoadjuvant therapy. Further comparisons between the standard neoadjuvant treatment and consolidation therapy groups showed no statistically significant differences in spincter-preservation rate or postoperative complication rates (both P>0.05). However, the consolidation therapy group had a longer interval between the end of radiotherapy and surgery [80.1 (50.8, 109.4) days vs. 61.8 (48.8, 74.8) days, P<0.001], and a higher incidence of chemotherapy-related adverse effects ([10/18] vs. 26.2% [17/65], P=0.018). Conclusion:In rectal cancer patients with poor response to neoadjuvant therapy and clear adverse prognostic features before surgery (locally advanced stage, MRF positive or EMVI positive), the addition of short- or long-course chemotherapy-based systemic therapy does not provide short- or long-term survival benefits. Moreover, an extended chemotherapy duration increases the incidence of chemotherapy-related adverse effects.

Objective:To compare the impact of different treatment strategies on the survival outcomes in rectal cancer patients with poor response to neoadjuvant therapy, and to explore the survival-related influencing factors.Methods:A retrospective cohort study was conducted. Between January 2018 and November 2022, the clinical, pathological, and follow-up data of 106 rectal cancer patients who received neoadjuvant therapy and were evaluated as grade 4 or 5 based on the Magnetic Resonance Tumor Regression Grade (mrTRG) from the rectal cancer database at Peking Union Medical College Hospital were retrospectively collected. Based on the post-neoadjuvant therapy assessment, patients were classified into three groups: the chemotherapy-radiotherapy group (23 patients), the consolidation therapy group (18 patients), and the standard treatment group (65 patients). General condition, pathological findings, selection of neoadjuvant therapy, comorbidities, as well as 3-year expected DMFS and OS were observed in the three groups.Results:All 106 patients were followed up, with a median follow-up time of 28 (21, 38) months. The overall 3-year DMFS rate was 60%, and the 3-year OS rate was 74%. The 3-year DMFS in the standard treatment and consolidation therapy groups were 74% and 72%, respectively; the 3-year OS were 84%, 81%, respectively. The Log-rank test showed that there was no significant difference in the 3-year expected DMFS and OS between the standard treatment group and the consolidation therapy group (both P>0.05), but both groups had better survival outcomes than the chemotherapy-radiotherapy group (10% and 39%, respectively; all P<0.001). Multivariate Cox regression analysis indicated that the chemotherapy-radiotherapy only regimen was an independent risk factor for DMFS (HR=12.425, 95% CI: 4.436–34.594, P<0.001), and the independent risk factors for OS were chemotherapy-radiotherapy only regimen (HR=8.991, 95%CI:2.220–36.403, P=0.002) and age≥65 years (HR=3.495, 95%CI: 1.017–12.009, P=0.047). Stratified analysis showed that chemotherapy-radiotherapy only regimen was the independent risk factors for DMFS and OS in patients with extramural vascular invasion (EMVI) positive ( n=66) and mesorectal fascial invasion (MRF) positive (n=56) (all P<0.05). Whether consolidation therapy was added to the standard neoadjuvant treatment regimen was not an independent factor affecting 3-year expected DMFS or OS in rectal cancer patients with poor response to neoadjuvant therapy. Further comparisons between the standard neoadjuvant treatment and consolidation therapy groups showed no statistically significant differences in spincter-preservation rate or postoperative complication rates (both P>0.05). However, the consolidation therapy group had a longer interval between the end of radiotherapy and surgery [80.1 (50.8, 109.4) days vs. 61.8 (48.8, 74.8) days, P<0.001], and a higher incidence of chemotherapy-related adverse effects ([10/18] vs. 26.2% [17/65], P=0.018). Conclusion:In rectal cancer patients with poor response to neoadjuvant therapy and clear adverse prognostic features before surgery (locally advanced stage, MRF positive or EMVI positive), the addition of short- or long-course chemotherapy-based systemic therapy does not provide short- or long-term survival benefits. Moreover, an extended chemotherapy duration increases the incidence of chemotherapy-related adverse effects.