Objective To explore the correlation between changes in spleen volume and stiffness before and after transjugular intrahepatic portosystemic shunt (TIPS) and the occurrence of hepatic encephalopathy. Methods A retrospective study was conducted on 104 patients who underwent TIPS in the Department of Interventional Therapy, Zhongshan Hospital, Fudan University, from January 1, 2023 to July 30, 2024. Spleen volume and stiffness were measured before and after surgery. Patients were divided into the overt hepatic encephalopathy (OHE) group and the non-OHE group. Univariate and multivariate logistic regression analyses were used to identify factors correlated with OHE after TIPS. The predictive values of the related factors of OHE were evaluated using receiver operating characteristic (ROC) curves. Results OHE occurred in 34 patients (32.69%). Compared with the non-OHE group, the OHE group had a smaller percentage reduction in spleen volume after TIPS (P＜0.001), but there was no statistically significant difference in the percentage reduction in spleen stiffness between the two groups. Multivariate logistic regression analysis revealed that the percentage reduction in spleen volume was correlated with postoperative OHE (OR＝0.90, P＜0.001). ROC analysis showed that the area under the curve (AUC) for spleen volume reduction percentage in predicting postoperative OHE was 0.773, superior to spontaneous portosystemic shunt (SPSS; Z＝2.088, P＝0.037). Conclusions Reduction in spleen volume after TIPS may be a protective factor against hepatic encephalopathy, while changes in spleen stiffness were not found to be correlated with its occurrence.

Demyelination and remyelination play key roles in spinal cord injury (SCI), affecting the recovery of motor and sensory functions. Research in rodent models is extensive, but the study of these processes in non-human primates is limited. Therefore, our goal was to thoroughly study the histological features of demyelination and remyelination after contusion injury of the cervical spinal cord in Macaca fascicularis. In a previous study, we created an SCI model in M. fascicularis by controlling the contusion displacement. We used Eriochrome Cyanine staining, immunohistochemical analysis, and toluidine blue staining to evaluate demyelination and remyelination. The results showed demyelination ipsilateral to the injury epicenter both rostrally and caudally, the former mainly impacting sensory pathways, while the latter primarily affected motor pathways. Toluidine blue staining showed myelin loss and axonal distension at the injury site. Schwann cell-derived myelin sheaths were only found at the center, while thinner myelin sheaths from oligodendrocytes were seen at the center and surrounding areas. Our study showed that long-lasting demyelination occurs in the spinal cord of M. fascicularis after SCI, with oligodendrocytes and Schwann cells playing a significant role in myelin sheath formation at the injury site.
Animals ; Spinal Cord Injuries/physiopathology* ; Demyelinating Diseases/etiology* ; Remyelination/physiology* ; Macaca fascicularis ; Disease Models, Animal ; Myelin Sheath/pathology* ; Oligodendroglia/pathology* ; Schwann Cells/pathology* ; Female ; Spinal Cord/pathology* ; Axons/pathology*

Objective To investigate the effects of inclined axial compressive force and flexion moment on the anterior and posterior shear stiffness of the lumbosacral segment.Methods Six fresh-frozen human cadaveric L5-S1 segments were tested under intact and two progressively impaired structural conditions:intact,a 4-mm bilateral facet joint gap,and anterior discectomy with nucleus pulposus removal plus circumferential release of the inner annular fibers(disc injury).A 300 N axial compressive force was applied either vertically downward or with a 10° or 20° anterior inclination through the disc's shear center.Anterior(0 N to 250 N)and posterior(-50 N to 0 N)shear tests were conducted using a material testing machine.These tests were repeated under a 5 N-m flexion moment.The relative motion between L5 and Si was measured using a three-dimensional motion capture system.Results In the intact state,the inclination of the axial compressive force did not significantly alter anterior or posterior shear stiffness.However,the application of a flexion moment increased anterior shear stiffness by 49.3％.Progressive structural damage resulted in incremental increases in anteroposterior shear translation and corresponding reductions in stiffness.Notably,under combined loading with axial compression and flexion moment,anterior stiffness decreased from 939 N/mm(intact)to 224 N/mm(disc injury),while posterior stiffness decreased from 572 N/mm to 217 N/mm.Within the low-load range,no significant differences in shear stiffness were observed across any structural conditions,regardless of axial force inclination or combined with a flexion moment.Conclusions This study supports the clinical view that retro-inclination of the pelvis serves as a compensatory mechanism to enhance segmental shear stability.However,this compensatory capacity gradually diminishes and ultimately fails as spinal degeneration progresses.

Objective:To explore the effectiveness of immersive virtual reality (VR)-guided core stability-assisted training in improving the balance of ischemic stroke survivors.Methods:Sixty-six hemiplegic ischemic stroke survivors were randomly divided into a conventional rehabilitation training group (CON) of 32 and an immersive VR-guided core stability-assisted training group (VR-TOT) of 34. In addition to basic internal medical treatment, the CON group underwent conventional rehabilitation therapy, while the VR-TOT group received VR-guided core stability-assisted training. Before and after 4 weeks of the treatments, the subjects′ balance was evaluated using the Fugl-Meyer balance scale. A three-dimensional force platform was used to collect the sway amplitude, sway speed, peripheral area and total trajectory length of the center of pressure COP of the bilateral plantar in the left-right and anterior-posterior directions while the subjects stood with the eyes open and closed.Results:After the treatments, the average Fugl-Meyer balance scores of both groups had improved significantly. In the eyes-open condition, after the treatment, there was a significant decrease in the average COP sway amplitude in the anteroposterior direction on the hemiplegic side among the CON group, as well as in both the mediolateral and anteroposterior directions on both sides in the VR-TOT group. The sway velocity in the anteroposterior direction on the hemiplegic side had decreased significantly in both groups, and the sway velocity in both the mediolateral and anteroposterior directions on the non-hemiplegic side had also decreased significantly. In the CON group the peripheral area on the non-hemiplegic side had decreased and the total trajectory length had shortened significantly. In the VR-TOT group there were significant decreases in the peripheral area on both sides and in the total trajectory length on both sides. Comparing the two groups after treatment, the peripheral area on the hemiplegic side in the VR-TOT group was significantly smaller. In the eyes-closed condition, the sway amplitude of the COP on the hemiplegic side in the anteroposterior direction and on the non-hemiplegic side in both the mediolateral and anteroposterior directions had decreased significantly in the VR-TOT group after the treatment. The average sway velocity had decreased significantly in the anteroposterior direction on the non-hemiplegic side in the CON group. In the VR-TOT group this was observed in the anteroposterior direction on the hemiplegic side and in both the mediolateral and anteroposterior directions on the healthy side. In the CON group the average peripheral area of the COP on the hemiplegic side had decreased, and the total trajectory length had shortened, both significantly. In the VR-TOT group, the peripheral area on the non-hemiplegic side had decreased significantly as well.Conclusions:Core stability-assisted training based on immersive virtual reality can effectively improve the balance of ischemic stroke survivors. It shows promise for clinical application.

Objective:To explore the clinical application value of MRI ultra-short echo time sequence (MRI-UTE) in the diagnosis of pulmonary nodules.Methods:This study was a cross-sectional study. A total of 101 consecutive patients were recruited prospectively from January to August 2024 at Huazhong Fuwai Hospital of Zhengzhou University. All of the included patients were diagnosed with pulmonary nodules by chest CT examination and intended for treatment. All patients underwent low-dose CT examination and MRI-UTE examination. The number, classification, and lung imaging reporting and data system (lung-RADS) grading of the pulmonary nodules were analyzed. Nodules classification was determined as solid nodules or sub-solid nodules, and sub-solid nodules included part-solid nodules and pure ground-glass nodules. Taking the evaluation results of radiologists with 10 and 12 years of experience in chest imaging diagnosis as the reference standard, the Kappa test was used to analyze the agreement of CT and MRI-UTE in terms of the accurate diagnosis, classification, and lung-RADS grading of pulmonary nodules. Results:Among the 101 patients, a total of 216 pulmonary nodules were identified. MRI-UTE accurately diagnosed 180 pulmonary nodules, while 203 pulmonary nodules were detected by CT. The concordance was moderate ( Kappa=0.48, P<0.001). In terms of nodule classification, CT correctly classified 167 nodules as solid and 36 as sub-solid, whereas MRI-UTE correctly classified 153 as solid and 23 as sub-solid, with good agreement (weighted Kappa=0.73, P<0.001). For lung-RADS grading, CT correctly graded 186 nodules, with 85 graded as category 2, 46 as category 3, 33 as category 4A, 12 as category 4B, and 10 as category 4X; MRI-UTE correctly graded 155 nodules, with 74 graded as category 2, 30 as category 3, 30 as category 4A, 12 as category 4B, and 9 as category 4X. The agreement between the two modalities in determining lung-RADS grade was also good (weighted Kappa=0.74, P<0.001). Conclusion:MRI-UTE demonstrates good agreement with CT in the accurate diagnosis, classification, and lung-RADS grading of pulmonary nodules, indicating certain clinical application value.

Objective:To explore the effectiveness of immersive virtual reality (VR)-guided core stability-assisted training in improving the balance of ischemic stroke survivors.Methods:Sixty-six hemiplegic ischemic stroke survivors were randomly divided into a conventional rehabilitation training group (CON) of 32 and an immersive VR-guided core stability-assisted training group (VR-TOT) of 34. In addition to basic internal medical treatment, the CON group underwent conventional rehabilitation therapy, while the VR-TOT group received VR-guided core stability-assisted training. Before and after 4 weeks of the treatments, the subjects′ balance was evaluated using the Fugl-Meyer balance scale. A three-dimensional force platform was used to collect the sway amplitude, sway speed, peripheral area and total trajectory length of the center of pressure COP of the bilateral plantar in the left-right and anterior-posterior directions while the subjects stood with the eyes open and closed.Results:After the treatments, the average Fugl-Meyer balance scores of both groups had improved significantly. In the eyes-open condition, after the treatment, there was a significant decrease in the average COP sway amplitude in the anteroposterior direction on the hemiplegic side among the CON group, as well as in both the mediolateral and anteroposterior directions on both sides in the VR-TOT group. The sway velocity in the anteroposterior direction on the hemiplegic side had decreased significantly in both groups, and the sway velocity in both the mediolateral and anteroposterior directions on the non-hemiplegic side had also decreased significantly. In the CON group the peripheral area on the non-hemiplegic side had decreased and the total trajectory length had shortened significantly. In the VR-TOT group there were significant decreases in the peripheral area on both sides and in the total trajectory length on both sides. Comparing the two groups after treatment, the peripheral area on the hemiplegic side in the VR-TOT group was significantly smaller. In the eyes-closed condition, the sway amplitude of the COP on the hemiplegic side in the anteroposterior direction and on the non-hemiplegic side in both the mediolateral and anteroposterior directions had decreased significantly in the VR-TOT group after the treatment. The average sway velocity had decreased significantly in the anteroposterior direction on the non-hemiplegic side in the CON group. In the VR-TOT group this was observed in the anteroposterior direction on the hemiplegic side and in both the mediolateral and anteroposterior directions on the healthy side. In the CON group the average peripheral area of the COP on the hemiplegic side had decreased, and the total trajectory length had shortened, both significantly. In the VR-TOT group, the peripheral area on the non-hemiplegic side had decreased significantly as well.Conclusions:Core stability-assisted training based on immersive virtual reality can effectively improve the balance of ischemic stroke survivors. It shows promise for clinical application.

Objective:To investigate the effects of learning flow experience on system thinking in medical students under the mixed mode.Methods:Medical students who completed Medical Statistics of the 2022-2023 academic year were enrolled.Then learning attitudes,learning flow experience,and system thinking were investigated using SATS-36 Scale,Adolescent Learning Flow Experience Questionnaire,and Systems Thinking Scale.Linear correlation analysis explored relationships among these variables.Multiple linear regression and restricted cubic spline(RCS)model analyzed linear/non-linear relationships between learning flow experience and system thinking after adjusting for gender,major,and learning attitude.Results:Among the 349 medical students surveyed,the mean score for learning attitudes was(4.31±0.59)and for learning flow experience was(3.33±0.65),both indicating a moderate to high level.The mean score for systems thinking was(59.01±13.57),indicating a moderate level.Positive correlations were found among learning flow experience,learning attitudes,and system thinking.Significant gender and major differences were observed in learning flow experience.After controlling for gender,major,and learning attitudes,multiple linear regression analysis revealed a significant linear trend between learning flow experience and system thinking(P＜0.01).RCS model analysis indicated a significant J-shaped nonlinear relationship between learning folw experience and system thinking(P for non-linearity＜0.01).Using the median score of 3.16 as the inflection point,when the learning flow experience score was＜3.16,it had no significant effect on medical students'system thinking(P=0.51).When the score was≥3.16,system thinking increased significantly with increasing learning flow experience(Beta per SD=0.56,95%CI:0.44-0.68,P＜0.01).Conclusions:The learning flow experience of medical students under the mixed mode can promote their system thinking.When the flow experience score is≥3.16,higher levels of learning flow experience are associated with increased systems thinking.Different dimensions of learning flow experience exhibit varying strengths of correlation with systems thinking.

Objective To investigate the effects of inclined axial compressive force and flexion moment on the anterior and posterior shear stiffness of the lumbosacral segment.Methods Six fresh-frozen human cadaveric L5-S1 segments were tested under intact and two progressively impaired structural conditions:intact,a 4-mm bilateral facet joint gap,and anterior discectomy with nucleus pulposus removal plus circumferential release of the inner annular fibers(disc injury).A 300 N axial compressive force was applied either vertically downward or with a 10° or 20° anterior inclination through the disc's shear center.Anterior(0 N to 250 N)and posterior(-50 N to 0 N)shear tests were conducted using a material testing machine.These tests were repeated under a 5 N-m flexion moment.The relative motion between L5 and Si was measured using a three-dimensional motion capture system.Results In the intact state,the inclination of the axial compressive force did not significantly alter anterior or posterior shear stiffness.However,the application of a flexion moment increased anterior shear stiffness by 49.3％.Progressive structural damage resulted in incremental increases in anteroposterior shear translation and corresponding reductions in stiffness.Notably,under combined loading with axial compression and flexion moment,anterior stiffness decreased from 939 N/mm(intact)to 224 N/mm(disc injury),while posterior stiffness decreased from 572 N/mm to 217 N/mm.Within the low-load range,no significant differences in shear stiffness were observed across any structural conditions,regardless of axial force inclination or combined with a flexion moment.Conclusions This study supports the clinical view that retro-inclination of the pelvis serves as a compensatory mechanism to enhance segmental shear stability.However,this compensatory capacity gradually diminishes and ultimately fails as spinal degeneration progresses.

Objective:To explore the clinical application value of MRI ultra-short echo time sequence (MRI-UTE) in the diagnosis of pulmonary nodules.Methods:This study was a cross-sectional study. A total of 101 consecutive patients were recruited prospectively from January to August 2024 at Huazhong Fuwai Hospital of Zhengzhou University. All of the included patients were diagnosed with pulmonary nodules by chest CT examination and intended for treatment. All patients underwent low-dose CT examination and MRI-UTE examination. The number, classification, and lung imaging reporting and data system (lung-RADS) grading of the pulmonary nodules were analyzed. Nodules classification was determined as solid nodules or sub-solid nodules, and sub-solid nodules included part-solid nodules and pure ground-glass nodules. Taking the evaluation results of radiologists with 10 and 12 years of experience in chest imaging diagnosis as the reference standard, the Kappa test was used to analyze the agreement of CT and MRI-UTE in terms of the accurate diagnosis, classification, and lung-RADS grading of pulmonary nodules. Results:Among the 101 patients, a total of 216 pulmonary nodules were identified. MRI-UTE accurately diagnosed 180 pulmonary nodules, while 203 pulmonary nodules were detected by CT. The concordance was moderate ( Kappa=0.48, P<0.001). In terms of nodule classification, CT correctly classified 167 nodules as solid and 36 as sub-solid, whereas MRI-UTE correctly classified 153 as solid and 23 as sub-solid, with good agreement (weighted Kappa=0.73, P<0.001). For lung-RADS grading, CT correctly graded 186 nodules, with 85 graded as category 2, 46 as category 3, 33 as category 4A, 12 as category 4B, and 10 as category 4X; MRI-UTE correctly graded 155 nodules, with 74 graded as category 2, 30 as category 3, 30 as category 4A, 12 as category 4B, and 9 as category 4X. The agreement between the two modalities in determining lung-RADS grade was also good (weighted Kappa=0.74, P<0.001). Conclusion:MRI-UTE demonstrates good agreement with CT in the accurate diagnosis, classification, and lung-RADS grading of pulmonary nodules, indicating certain clinical application value.

Objective:To investigate the effects of learning flow experience on system thinking in medical students under the mixed mode.Methods:Medical students who completed Medical Statistics of the 2022-2023 academic year were enrolled.Then learning attitudes,learning flow experience,and system thinking were investigated using SATS-36 Scale,Adolescent Learning Flow Experience Questionnaire,and Systems Thinking Scale.Linear correlation analysis explored relationships among these variables.Multiple linear regression and restricted cubic spline(RCS)model analyzed linear/non-linear relationships between learning flow experience and system thinking after adjusting for gender,major,and learning attitude.Results:Among the 349 medical students surveyed,the mean score for learning attitudes was(4.31±0.59)and for learning flow experience was(3.33±0.65),both indicating a moderate to high level.The mean score for systems thinking was(59.01±13.57),indicating a moderate level.Positive correlations were found among learning flow experience,learning attitudes,and system thinking.Significant gender and major differences were observed in learning flow experience.After controlling for gender,major,and learning attitudes,multiple linear regression analysis revealed a significant linear trend between learning flow experience and system thinking(P＜0.01).RCS model analysis indicated a significant J-shaped nonlinear relationship between learning folw experience and system thinking(P for non-linearity＜0.01).Using the median score of 3.16 as the inflection point,when the learning flow experience score was＜3.16,it had no significant effect on medical students'system thinking(P=0.51).When the score was≥3.16,system thinking increased significantly with increasing learning flow experience(Beta per SD=0.56,95%CI:0.44-0.68,P＜0.01).Conclusions:The learning flow experience of medical students under the mixed mode can promote their system thinking.When the flow experience score is≥3.16,higher levels of learning flow experience are associated with increased systems thinking.Different dimensions of learning flow experience exhibit varying strengths of correlation with systems thinking.