Stroke can cause Wallerian degeneration in regions outside of the brain,particularly in the corticospinal tract.To investigate the fate of major glial cells and axons within affected areas of the corticospinal tract f...Stroke can cause Wallerian degeneration in regions outside of the brain,particularly in the corticospinal tract.To investigate the fate of major glial cells and axons within affected areas of the corticospinal tract following stroke,we induced photochemical infarction of the sensorimotor cortex leading to Wallerian degeneration along the full extent of the corticospinal tract.We first used a routine,sensitive marker of axonal injury,amyloid precursor protein,to examine Wallerian degeneration of the corticospinal tract.An antibody to amyloid precursor protein mapped exclusively to proximal axonal segments within the ischemic cortex,with no positive signal in distal parts of the corticospinal tract,at all time points.To improve visualization of Wallerian degeneration,we next utilized an orthograde virus that expresses green fluorescent protein to label the corticospinal tract and then quantitatively evaluated green fluorescent protein-expressing axons.Using this approach,we found that axonal degeneration began on day 3 post-stroke and was almost complete by 7 days after stroke.In addition,microglia mobilized and activated early,from day 7 after stroke,but did not maintain a phagocytic state over time.Meanwhile,astrocytes showed relatively delayed mobilization and a moderate response to Wallerian degeneration.Moreover,no anterograde degeneration of spinal anterior horn cells was observed in response to Wallerian degeneration of the corticospinal tract.In conclusion,our data provide evidence for dynamic,pathogenic spatiotemporal changes in major cellular components of the corticospinal tract during Wallerian degeneration.展开更多
The spatial arrangement of the cell is important and considered as underlying mechanism for mathematical modeling of cell to cell interaction.The ability of cells to take on the characteristics of other cells in an or...The spatial arrangement of the cell is important and considered as underlying mechanism for mathematical modeling of cell to cell interaction.The ability of cells to take on the characteristics of other cells in an organism,it is important to understand the dynamical behavior of the cells.This method implements experimental parameters of the cell-cell interaction into the mathematical simulation of cell arrangement.The purpose of this research was to explore the three-dimensional spatial distribution of anterior horn cells in the rat spinal cord to examine differences after sciatic nerve injury.Sixteen Sprague-Dawley male rats were assigned to control and axotomy groups.Twelve weeks after surgery,the anterior horn was removed for first-and second-order stereological studies.Second-order stereological techniques were applied to estimate the pair correlation and cross-correlation functions using a dipole probe superimposed onto the spinal cord sections.The findings revealed 7% and 36% reductions in the mean volume and total number of motoneurons,respectively,and a25% increase in the neuroglial cell number in the axotomized rats compared to the control rats.In contrast,the anterior horn volume remained unchanged.The results also indicated a broader gap in the pair correlation curve for the motoneurons and neuroglial cells in the axotomized rats compared to the control rats.This finding shows a negative correlation for the distribution of motoneurons and neuroglial cells in the axotomized rats.The cross-correlation curve shows a negative correlation between the motoneurons and neuroglial cells in the axotomized rats.These findings suggest that cellular structural and functional changes after sciatic nerve injury lead to the alterations in the spatial arrangement of motoneurons and neuroglial cells,finally affecting the normal function of the central nervous system.The experimental protocol was reviewed and approved by the Animal Ethics Committee of Shahid Beheshti University of Medical Sciences(approval No.IR.SBMU.MSP.REC1395.375) on October 17,2016.展开更多
Bone marrow mesenchymal stem cell transplantation has been shown to be therapeutic in the repair of spinal cord injury. However, the low survival rate of transplanted bone marrow mesen- chymal stem cells in vivo remai...Bone marrow mesenchymal stem cell transplantation has been shown to be therapeutic in the repair of spinal cord injury. However, the low survival rate of transplanted bone marrow mesen- chymal stem cells in vivo remains a problem. Neurotrophin-3 promotes motor neuron survival and it is hypothesized that its transfection can enhance the therapeutic effect. We show that in vitro transfection of neurotrophin-3 gene increases the number of bone marrow mesenchymal stem cells in the region of spinal cord injury. These results indicate that neurotrophin-3 can promote the survival of bone marrow mesenchymal stem cells transplanted into the region of spinal cord injury and potentially enhance the therapeutic effect in the repair of spinal cord injury.展开更多
Sericin from discarded silkworm cocoons of silk reeling has been used in different fields, such as cosmetology, skin care, nutrition, and oncology. The present study established a rat model of type 2 diabetes by conse...Sericin from discarded silkworm cocoons of silk reeling has been used in different fields, such as cosmetology, skin care, nutrition, and oncology. The present study established a rat model of type 2 diabetes by consecutive intraperitoneal injections of low-dose （25 mg/kg） streptozotocin. After intragastrical perfusion of sericin for 35 days, blood glucose levels significantly declined, and the expression of neurofilament protein in the sciatic nerve and nerve growth factor in L4-6 spinal ganglion and anterior horn cells significantly increased. However, the expression of neuropeptide Y in spinal ganglion and anterior horn cells significantly decreased in model rats. These findings indicate that sericin protected the sciatic nerve and related nerve cells against injury in a rat type 2 diabetic model by upregulating the expression of neurofilament protein in the sciatic nerve and nerve growth factor in spinal ganglion and anterior horn cells, and downregulating the expression of neuropeptide Y in spinal ganglion and anterior horn cells.展开更多
背景:肌萎缩型颈椎病治疗方法仍有争议。对于肌萎缩型颈椎病患者,保守治疗一般可以稳定或者改善症状,但无法治愈。进展性或严重的神经功能恶化的肌萎缩型颈椎病推荐手术治疗,但多数临床医师根据自己的临床经验选择手术方式,尚未达成统...背景:肌萎缩型颈椎病治疗方法仍有争议。对于肌萎缩型颈椎病患者,保守治疗一般可以稳定或者改善症状,但无法治愈。进展性或严重的神经功能恶化的肌萎缩型颈椎病推荐手术治疗,但多数临床医师根据自己的临床经验选择手术方式,尚未达成统一的标准或行业共识。不同分型的肌萎缩型颈椎病预后显著不同,可能影响手术方案选的选择。目的:通过对肌萎缩型颈椎病相关研究进行综述,总结并分析疾病发病机制、临床表现、分型、诊断、治疗和预后情况,以期为此病的临床治疗和手术方案选择提供参考。方法:通过计算机检索1952-2020年发表在PubMed、EMbase、Web of Science、中国知网和万方数据库的肌萎缩型颈椎病相关研究文章,选择符合纳入标准的44篇文献进行综述。结果与结论:(1)肌萎缩型颈椎病的临床表现以上肢运动无力伴有明显的肌肉萎缩,而下肢没有明显的感觉障碍或痉挛性麻痹为特征,具有不对称性、节段性等特点;(2)临床多采用依据肌肉萎缩位置的不同进行分型,分为近端型、远端型和混合型,该疾病需与运动神经元病、肌肉营养不良疾病相鉴别,避免误诊和误治;(3)目前关于肌萎缩型颈椎病的发病机制尚不清楚,有腹侧神经根和脊髓前角细胞损伤两种观点,后者得到大部分学者认可;(4)肌萎缩型颈椎病的诊断主要依据临床症状、影像学检查及神经电生理检查,鉴别诊断上主要需排除运动神经元病等;(5)肌萎缩型颈椎病的治疗以手术为主,颈椎前路前路手术是治疗首选,而对于多节段颈椎后纵韧带骨化、前路不可能减压或者减压风险太大的患者需选择后路手术;(6)不同类型肌萎缩型颈椎病患者术后取得的预后效果有一定差异,其中近端型较远端型预后效果更佳,混合型预后最差,颈椎前路较后路手术效果佳。展开更多
基金supported by the National Natural Science Foundation of China,Nos.31 730030 (to XL),81941011 (to XL),31 771053 (to HD),82271403 (to XL),82272171 (to ZY),31971279 (to ZY)82201542 (to FH)+1 种基金the Natural Science Foundation of Beijing,No.7222004 (to HD)the Science and Technology Program of Beijing,No.Z181100001818007(to ZY)
文摘Stroke can cause Wallerian degeneration in regions outside of the brain,particularly in the corticospinal tract.To investigate the fate of major glial cells and axons within affected areas of the corticospinal tract following stroke,we induced photochemical infarction of the sensorimotor cortex leading to Wallerian degeneration along the full extent of the corticospinal tract.We first used a routine,sensitive marker of axonal injury,amyloid precursor protein,to examine Wallerian degeneration of the corticospinal tract.An antibody to amyloid precursor protein mapped exclusively to proximal axonal segments within the ischemic cortex,with no positive signal in distal parts of the corticospinal tract,at all time points.To improve visualization of Wallerian degeneration,we next utilized an orthograde virus that expresses green fluorescent protein to label the corticospinal tract and then quantitatively evaluated green fluorescent protein-expressing axons.Using this approach,we found that axonal degeneration began on day 3 post-stroke and was almost complete by 7 days after stroke.In addition,microglia mobilized and activated early,from day 7 after stroke,but did not maintain a phagocytic state over time.Meanwhile,astrocytes showed relatively delayed mobilization and a moderate response to Wallerian degeneration.Moreover,no anterograde degeneration of spinal anterior horn cells was observed in response to Wallerian degeneration of the corticospinal tract.In conclusion,our data provide evidence for dynamic,pathogenic spatiotemporal changes in major cellular components of the corticospinal tract during Wallerian degeneration.
基金supported by the Research Vice-chancellor of Shahid Beheshti University of Medical Sciences,Tehran,Iran(No.1394-373 to RMF)
文摘The spatial arrangement of the cell is important and considered as underlying mechanism for mathematical modeling of cell to cell interaction.The ability of cells to take on the characteristics of other cells in an organism,it is important to understand the dynamical behavior of the cells.This method implements experimental parameters of the cell-cell interaction into the mathematical simulation of cell arrangement.The purpose of this research was to explore the three-dimensional spatial distribution of anterior horn cells in the rat spinal cord to examine differences after sciatic nerve injury.Sixteen Sprague-Dawley male rats were assigned to control and axotomy groups.Twelve weeks after surgery,the anterior horn was removed for first-and second-order stereological studies.Second-order stereological techniques were applied to estimate the pair correlation and cross-correlation functions using a dipole probe superimposed onto the spinal cord sections.The findings revealed 7% and 36% reductions in the mean volume and total number of motoneurons,respectively,and a25% increase in the neuroglial cell number in the axotomized rats compared to the control rats.In contrast,the anterior horn volume remained unchanged.The results also indicated a broader gap in the pair correlation curve for the motoneurons and neuroglial cells in the axotomized rats compared to the control rats.This finding shows a negative correlation for the distribution of motoneurons and neuroglial cells in the axotomized rats.The cross-correlation curve shows a negative correlation between the motoneurons and neuroglial cells in the axotomized rats.These findings suggest that cellular structural and functional changes after sciatic nerve injury lead to the alterations in the spatial arrangement of motoneurons and neuroglial cells,finally affecting the normal function of the central nervous system.The experimental protocol was reviewed and approved by the Animal Ethics Committee of Shahid Beheshti University of Medical Sciences(approval No.IR.SBMU.MSP.REC1395.375) on October 17,2016.
基金supported by Scientific Research Fund of Xinxiang Medical University,No.2013ZD120Science and Technology Innovation Talents in Universities in Ministry of Education of Henan Province in 2010,No.2010HASTIT036
文摘Bone marrow mesenchymal stem cell transplantation has been shown to be therapeutic in the repair of spinal cord injury. However, the low survival rate of transplanted bone marrow mesen- chymal stem cells in vivo remains a problem. Neurotrophin-3 promotes motor neuron survival and it is hypothesized that its transfection can enhance the therapeutic effect. We show that in vitro transfection of neurotrophin-3 gene increases the number of bone marrow mesenchymal stem cells in the region of spinal cord injury. These results indicate that neurotrophin-3 can promote the survival of bone marrow mesenchymal stem cells transplanted into the region of spinal cord injury and potentially enhance the therapeutic effect in the repair of spinal cord injury.
文摘Sericin from discarded silkworm cocoons of silk reeling has been used in different fields, such as cosmetology, skin care, nutrition, and oncology. The present study established a rat model of type 2 diabetes by consecutive intraperitoneal injections of low-dose （25 mg/kg） streptozotocin. After intragastrical perfusion of sericin for 35 days, blood glucose levels significantly declined, and the expression of neurofilament protein in the sciatic nerve and nerve growth factor in L4-6 spinal ganglion and anterior horn cells significantly increased. However, the expression of neuropeptide Y in spinal ganglion and anterior horn cells significantly decreased in model rats. These findings indicate that sericin protected the sciatic nerve and related nerve cells against injury in a rat type 2 diabetic model by upregulating the expression of neurofilament protein in the sciatic nerve and nerve growth factor in spinal ganglion and anterior horn cells, and downregulating the expression of neuropeptide Y in spinal ganglion and anterior horn cells.
文摘背景:肌萎缩型颈椎病治疗方法仍有争议。对于肌萎缩型颈椎病患者,保守治疗一般可以稳定或者改善症状,但无法治愈。进展性或严重的神经功能恶化的肌萎缩型颈椎病推荐手术治疗,但多数临床医师根据自己的临床经验选择手术方式,尚未达成统一的标准或行业共识。不同分型的肌萎缩型颈椎病预后显著不同,可能影响手术方案选的选择。目的:通过对肌萎缩型颈椎病相关研究进行综述,总结并分析疾病发病机制、临床表现、分型、诊断、治疗和预后情况,以期为此病的临床治疗和手术方案选择提供参考。方法:通过计算机检索1952-2020年发表在PubMed、EMbase、Web of Science、中国知网和万方数据库的肌萎缩型颈椎病相关研究文章,选择符合纳入标准的44篇文献进行综述。结果与结论:(1)肌萎缩型颈椎病的临床表现以上肢运动无力伴有明显的肌肉萎缩,而下肢没有明显的感觉障碍或痉挛性麻痹为特征,具有不对称性、节段性等特点;(2)临床多采用依据肌肉萎缩位置的不同进行分型,分为近端型、远端型和混合型,该疾病需与运动神经元病、肌肉营养不良疾病相鉴别,避免误诊和误治;(3)目前关于肌萎缩型颈椎病的发病机制尚不清楚,有腹侧神经根和脊髓前角细胞损伤两种观点,后者得到大部分学者认可;(4)肌萎缩型颈椎病的诊断主要依据临床症状、影像学检查及神经电生理检查,鉴别诊断上主要需排除运动神经元病等;(5)肌萎缩型颈椎病的治疗以手术为主,颈椎前路前路手术是治疗首选,而对于多节段颈椎后纵韧带骨化、前路不可能减压或者减压风险太大的患者需选择后路手术;(6)不同类型肌萎缩型颈椎病患者术后取得的预后效果有一定差异,其中近端型较远端型预后效果更佳,混合型预后最差,颈椎前路较后路手术效果佳。
