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Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Early postural adjustments serve as preparatory measures for forthcoming actions or potential disruptions in posture, thereby facilitating improved movement execution and mitigating destabilizing effects caused by posture interference. OBJECTIVE: To investigate the characteristics of temporal and intensity parameters of key lower limb muscles during early postural adjustment phase when stroke patients with varying levels of balance initiate walking at a self-selected comfortable pace. METHODS: The characteristics of early postural adjustments in 16 stroke patients were observed. Sixteen patients were divided into a non-fall group (n=8) and a fall group (n=8) based on the history of falls and Berg Balance Scale scores. Noraxon inertial sensors and Noraxon Ultium EMG wireless surface electromyography were utilized to collect body kinematic data and surface electromyography data during gait initiation. Muscle activation time and activation sequence of six key muscles in the lower limbs (tibialis anterior, medial and lateral gastrocnemius, rectus femoris, lateral femoris and biceps femoris muscles) during the early postural adjustment phase, as well as normalized electromyography integral values for the four time windows (each 150 ms) before gait initiation, were analyzed. RESULTS AND CONCLUSION: Stroke patients with a history of falls exhibited earlier activation times for the six key muscles in the lower limbs during gait initiation compared with those in the non-fall group. The fall group demonstrated significantly earlier activation times for tibialis anterior, lateral head of gastrocnemius, and vastus lateralis (P < 0.01, P < 0.05). In contrast, the non-fall group displayed a consistent pattern of activating extensor muscles before flexor muscles, with thigh muscle activation preceding calf muscle activation. However, in the fall group, calf extensor muscle activation occurred prior to thigh extensor muscle activation, and the vastus lateralis was activated even earlier. The tibialis anterior was the last activated muscle in both groups. Specifically during T3 (> -300 to -150 ms), the tibialis anterior exhibited significantly higher activity in the fall group compared with the non-fall group (P < 0.05), while the lateral head of gastrocnemius demonstrated significant inhibition during T3 (P < 0.05) and the medial head of gastrocnemius showed significant inhibition during both T3 and T4 (> -150 to 0 ms) stages compared with the non-fall group (P < 0.01, P < 0.05). To conclude, stroke patients with varying balance abilities employ distinct early postural adjustment strategies prior to stepping, as evidenced by differences in muscle activation timing, recruitment order, and muscle activity amplitude. Patients at a high risk of falling exhibit prolonged duration of early postural adjustment and delayed initiation of gait, indicating earlier activation of the tibialis anterior muscle and inhibition of gastrocnemius muscle activity. These delays in gait initiation and variations in muscle recruitment strategies may contribute to unstable posture and an increased susceptibility to falls. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Bone tissue engineering scaffolds have been widely used in recent years, but their stability and controllability are poor, which may produce stress concentration easily. Triply periodic minimal surfaces have many advantages, such as porosity, smoothness, connectivity, diversity and controllability, which provide a new idea for the design and application of bone tissue scaffolds. OBJECTIVE: To construct bone trabecular structure based on implicit surface method and optimize the structure by using finite element numerical simulation and topology optimization technology. METHODS: (1) Based on the parameterization of implicit surface method and modeling S-P, D and G trabecular structures of triply periodic minimal surface were constructed. (2) Compression simulation of the constructed trabecular bone structure was carried out using finite element numerical simulation method. (3) The structure optimization of S-P bone trabecular structure was carried out by using variable density method and Solid Isotropic Material with Penalization interpolation model. RESULTS AND CONCLUSION: (1) The stress nephogram showed that the three trabecular structures exhibited larger stress values at the intersection of the unit structures. The S-P type appeared at the radial connection of the unit. The G type appeared at the axial connection. The D type appeared at the axial and radial connection. The equivalent stresses of S-P, G and D structures were 105.07, 694.78 and 637.36 MPa, respectively. (2) The displacement nephogram showed that the displacement of the three trabecular structures close to the displacement surface was the largest and decreased along the axial direction. The total deformation of the S-P type was smaller than that of the G and D types. (3) The porosity of the three trabecular bone structures was higher than 50%, with the highest porosity of the S-P type (90.7%) and an aperture of 0.63 mm. Bone ingrowth performance was better than G and D types. (4) After topology optimization, the equivalent stress of S-P structure was 149.11 MPa, the mass of which was reduced by 13.9%, which met the design requirements of bone tissue scaffold. (5) Therefore, the method of the design of bone trabecular structure that combines triply periodic minimal surface parametric modeling with finite element numerical simulation and topology optimization provides a new idea for the surface structure design of bone implants. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Enriched environment intervention can improve cognitive impairment to a certain extent. Glutamate is an excitatory amino acid closely related to cognition. The effect and mechanism of enriched environment on glutamate receptor in post-stroke mice are still unclear. OBJECTIVE: To investigate the effect of metabotropic glutamate receptor on improving post-stroke cognitive impairment and its mechanism in enriched environments. METHODS: The mouse model of stroke was made by light embolus method, and the mice with cognitive impairment were selected through Y maze test in comparison with the sham operation group. The mice were randomly divided into three groups: sham operation+standard environment operation group (Sham+SE), post-stroke cognitive impairment+standard environment (PSCI+SE) group and post-stroke cognitive impairment+enriched environment (PSCI+EE) group. After 14 days in the corresponding environment, Y maze was used to detect the cognitive function of the frontal lobe. New object recognition experiment was used to detect the learning and memory ability of the hippocampus. Quantitative real-time PCR was used to detect the mRNA transcription level of metabotropic glutamate receptor in the frontal lobe and hippocampus, and western blot was used to detect the protein expression of metabotropic glutamate receptor, acetylated histone H3, CAMP response binding protein in the frontal lobe and hippocampus. RESULTS AND CONCLUSION: Compared with the Sham+SE group, the Y maze spontaneous alternation rate was significantly decreased (P < 0.001), the new object exploration rate was significantly decreased (P < 0.001), metabotropic glutamate receptor mRNA levels in the frontal lobe and hippocampus were downregulated (P < 0.01), and the expression of related proteins in the frontal lobe and hippocampus was significantly decreased in the PSCI+SE group (P < 0.01). The spontaneous alternation rate, new object exploration rate, and metabolic glutamate receptor mRNA in the frontal lobe and hippocampus were significantly decreased, and mRNA transcription, frontal lobe and hippocampus related protein expression were significantly improved in the PSCI+EE group compared with the PSCI+SE group (P < 0.05), but there was still a significant difference between PSCI+EE group and Sham+SE group (P < 0.05). To conclude, enriched environment intervention is helpful to improve the memory of mice after stroke, and its mechanism may be through increasing the phosphorylation of CAMP response binding protein, acetylation homeostasis imbalance, increasing metabotropic glutamate receptor 2 mRNA transcription and protein expression, and ultimately improving cognitive function. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: For lumbar disc herniation, interleukin-23 promotes the Th17 cells to secrete interleukin-17, and then interleukin-17 cooperates with tumor necrosis factor-α to produce inflammation mediators. It would aggravate inflammation and autoimmune response, and then cause some symptoms such as sciatica. OBJECTIVE: To explore the association between interleukin-23/Th17 axis and lumbar disc herniation. METHODS: Thirty-eight samples of nucleus pulposus were selected, of which 30 were taken from patients with lumbar disc herniation (trial group) and 8 from patients with lumbar vertebral fractures (control group). Peripheral blood samples were meanwhile taken from two groups of patients on admission. All patients, who were admitted to the Department of Spine Surgery, Affiliated Hospital of Nantong University, were diagnosed based on clinical symptoms, imaging examinations and intraoperative confirmation. Immunohistochemical method was used to detect the expression of interleukin 23 in the nucleus pulposus tissue, and ELISA assay was used to detect the levels of interleukin 17, interleukin 23, and tumor necrosis factor-α in the nucleus pulposus tissue and peripheral blood. Pearson correlation analysis was then performed. RESULTS AND CONCLUSION: Immunohistochemistry detection showed that the expression of interleukin-23 was significantly higher in the trial group than the control group (P < 0.01). The levels of interleukin-17, interleukin-23 and tumor necrosis factor-α in the nucleus pulpous and peripheral blood all significantly increased in the trial group compared with the control group (P < 0.01). There was a significant positive correlation between these three cytokines in the nucleus pulposus tissue of the trial group (r > 0.5, P < 0.01). To conclude, lumbar disc herniation is closely related to interleukin-23/Th17 axis inflammatory response. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Heparin-binding epidermal growth factor-like growth factor (HB-EGF) plays an important role in bone development. However, there is no report regarding the effects of HB-EGF derived from bone marrow mesenchymal stem cells on skeletal development. OBJECTIVE: To study the effects of HB-EGF overexpression in bone marrow mesenchymal stem cells on skeletal development and to preliminarily explore the underlying mechanisms. METHODS: The mouse model of HB-EGF overexpression in Prrx1+ bone marrow mesenchymal stem cells (ROSA26tm1(HB-EGF); Prrx1-Cre) was constructed using Cre-LoxP system. Bone sections were processed and stained for histological analysis. Mouse bone marrow mesenchymal stem cells were cultured in vitro and their differentiation potential and relevant molecular mechanism were assessed. The experiment was approved by the Experimental Animal Management, Academics, Ethics and Use Committee of Shanghai Jiao Tong University in 2015. The approval number is A2015027. RESULTS AND CONCLUSION: (1) Prrx1 was expressed in the articular cartilage, growth plate, trabecular bone and periosteum of adult mice. (2) The femurs of ROSA26tm1(HB-EGF); Prrx1-Cre mice were shortened, the bone mass decreased significantly, and the cartilage morphology and structure were abnormal, all of which indicated osteoarthritic phenotype. (3) Overexpression of HB-EGF inhibited the osteogenic and chondrogenic differentiation of bone marrow mesenchymal stem cells from ROSA26tm1(HB-EGF); Prrx1-Cre mice in vitro. These results suggest that overexpression of HB-EGF in Prrx1+ bone marrow mesenchymal stem cells may influence the skeletal development by inhibiting osteogenic and chondrogenic differentiation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Establishing the rat model of ulcerative colitis by 2,4,6-trinitrobenzene sulfonic acid (TNBS)/ethanol method is easy to operate, has long duration and the histological changes are similar to human ulcerative colitis, which is commonly used animal model. However, the optimal dose and modeling times still remain controversial. OBJECTIVE: To establish the rat model of the severe ulcerative colitis by different times of different doses of TNBS/ethanol, and to explore the optimal modeling times. METHODS: Eighty Sprague-Dawley rats, SPF level, were provided by Hunan Slack Jingda Experimental Animal Co., Ltd., and the study was approved by the Experimental Animal Ethics Committee of the First Affiliated Hospital of Guangxi University of Chinese Medicine, approval number: 2013(KF)-E-003. The rats were randomly divided into normal control group, and TNBS/ethanol (100 mg/kg once, 100 mg/kg twice, and 100 mg/kg thrice) group. The rats were intragastrically injected with TNBS/ethanol through rectum for 1, 2, and 3 days continuously. Then ten rats were killed at 3 and 7 days after administration, so as to observe the physiological status, colon morphology, disease activity index and histopathological changes. RESULTS AND CONCLUSION: (1) At 7 days after modeling, the body mass of rats progressively decreased and symptoms gradually exacerbated with the modeling times increased. The disease activity index was on a rise. (2) The body mass in the TNBS/ethanol thrice group was significantly lower than that in the other groups (P < 0.05), and the disease activity index and gross scores were significantly higher than those in the other groups (P < 0.05). (3) The pathological results showed that the TNBS/ethanol thrice group caused the lesions located in the colonic mucosa and muscularis, the goblet cells lost, irregular crypts in shape, disordered arrangement and the most of visible ulcers, which were more consistent with the pathological manifestations of severe ulcerative colitis than the other two groups. (4) In summary, in the TNBS/ethanol modeling, using 100 mg/kg TNBS/ethanol thrice is more consistent with the model of severe ulcerative colitis. [ABSTRACT FROM AUTHOR]