Therapies such as direct tension-free microsurgical repair or transplantation of a nerve autograft,are nowadays used to treat traumatic peripheral nerve injuries（PNI）,focused on the enhancement of the intrinsic rege...Therapies such as direct tension-free microsurgical repair or transplantation of a nerve autograft,are nowadays used to treat traumatic peripheral nerve injuries（PNI）,focused on the enhancement of the intrinsic regenerative potential of injured axons.However,these therapies fail to recreate the suitable cellular and molecular microenvironment of peripheral nerve repair and in some cases,the functional recovery of nerve injuries is incomplete.Thus,new biomedical engineering strategies based on tissue engineering approaches through molecular intervention and scaffolding offer promising outcomes on the field.In this sense,evidence is accumulating in both,preclinical and clinical settings,indicating that platelet-rich plasma products,and fibrin scaffold obtained from this technology,hold an important therapeutic potential as a neuroprotective,neurogenic and neuroinflammatory therapeutic modulator system,as well as enhancing the sensory and motor functional nerve muscle unit recovery.展开更多
Each year approximately 360,000 people in the United States suffer a peripheral nerve injury （PNI）, which is a leading source of lifelong disability （Kelsey et al., 1997; Noble et al., 1998）. The most frequent cau...Each year approximately 360,000 people in the United States suffer a peripheral nerve injury （PNI）, which is a leading source of lifelong disability （Kelsey et al., 1997; Noble et al., 1998）. The most frequent cause of PNIs is motor vehicle accidents, while gunshot wounds, stabbings, and birth trauma are also common factors. Patients suffering from disabilities as a result of their PNIs are also burdensome to the healthcare system, with aver- age hospital stays of 28 days each year （Kelsey et al., 1997; Noble et al., 1998）.展开更多
In China, there are approximately 20 million people suffering from peripheral nerve injury and this number is increasing at a rate of 2 million per year. These patients cannot live or work independently and are a heav...In China, there are approximately 20 million people suffering from peripheral nerve injury and this number is increasing at a rate of 2 million per year. These patients cannot live or work independently and are a heavy responsibility on both family and society because of extreme disability and dysfunction caused by peripheral nerve injury （PNI）. Thus, repair of PNI has become a major public health issue in China.展开更多
The peripheral nervous system （PNS） is composed of the nerves and ganglia outside of the brain and spinal cord whose primary function is to connect the central nervous system to the limbs and organs. A peripheral ne...The peripheral nervous system （PNS） is composed of the nerves and ganglia outside of the brain and spinal cord whose primary function is to connect the central nervous system to the limbs and organs. A peripheral nerve injury （PNI） is damage to the nerves and/or its surrounding tissue. These injuries can affect up to 5% of patients that are hospitalized for trauma （Taylor et al., 2008） and over 50,000 surgical repair procedures are performed annually in the United States alone （Evans, 2001）.展开更多
Who drew the borders between central and peripheral nervous sys tem？ A complex question but a simple answer. Human anatomy and clinical neurology need to differentiate peripheral nerves from central nervous system ...Who drew the borders between central and peripheral nervous sys tem？ A complex question but a simple answer. Human anatomy and clinical neurology need to differentiate peripheral nerves from central nervous system （CNS）, peripheral or central disorders, respectively. However, there are no anatomical and functional clefts between peripheral axons and central synaps- es. There is a direct continuity from the periphery to the center, from the receptor to the sensory neuron, from the spinal motor neuron to the muscle, just the neuromuscular junction.展开更多
Peripheral nerve injuries （PNI） are a major clinical prob- lem. In general, PNI results from motor vehicle accidents, lacerations with sharp objects, penetrating trauma （gunshot wounds） and stretching or crushing ...Peripheral nerve injuries （PNI） are a major clinical prob- lem. In general, PNI results from motor vehicle accidents, lacerations with sharp objects, penetrating trauma （gunshot wounds） and stretching or crushing trauma and fractures. It is estimated that PNI occur in 2.8% of trauma patients and this number reaches 5% if plexus and root lesions are in- cluded. However, due to lack of recent epidemiological stud- ies, these data probably underestimate the actual number of nerve injuries展开更多
Objective： To explore the clinical value of the radical nerve dissection （RND） for the carcinoma of head of pancreas （CHP）. Methods： The clinical and pathological data of 30 CHP patients who underwent RND in our...Objective： To explore the clinical value of the radical nerve dissection （RND） for the carcinoma of head of pancreas （CHP）. Methods： The clinical and pathological data of 30 CHP patients who underwent RND in our hospital were retrospectively analyzed, with an attempt to explore the safety and short-term efficacy of this procedure. Results： Among these 30 patients, the operative time was （351±61） rain, the intra-operative blood loss was 350 （range, 300-600） mL, and the grades B and C pancreatic fistula was 23.33%. During the follow-up （range, 2-30 months; median： 17 months）, the 1-year survival rate was 63.33% and the 1-year disease-free survival rate was 56.67%. Among the 23 patients （76.66%） with positive extra-pancreatic perineural invasion （PNI）, the 1-year case- fatality rate was 34.78%, which was not significantly different from that （28.57%） of patients with negative PNI （P=0.760）. Conclusions： Our results suggested potential advantages of RND in the fields of surgery-associated risk and prognosis compared with the Whipple operation in the treatment of CHP. Due to the low sample size of this study, further well-designed research of large sample size is needed.展开更多
The functional recovery of peripheral nerve injury(PNI)is unsatisfactory,whereas diabetes mellitus(DM)and its related complications further attenuate the restoration of diabetic PNI(DPNI).Adipose-derived stem cells(AD...The functional recovery of peripheral nerve injury(PNI)is unsatisfactory,whereas diabetes mellitus(DM)and its related complications further attenuate the restoration of diabetic PNI(DPNI).Adipose-derived stem cells(ADSCs)are promising candidates for treatment of DPNI due to their abundant source,excellent differentiation and paracrine ability.Our results showed that ADSCs remarkably enhanced the proliferation and migration of Schwann cells and endothelial cells,and tube formation.Mechanistically,ADSCs could regulate Nrf2/HO-1,NF-κB and PI3K/AKT/mTOR signaling pathways,showing multiple functions in reducing oxidative stress and inflammation,and regulating cell metabolism,growth,survival,proliferation,angiogenesis,differentiation of Schwann cell and myelin formation.In current study,novel graphene foam(GF)/hydrogel-based scaffold was developed to deliver ADSCs for treatment of DPNI.GF/hydrogel scaffold exhibited excellent mechanical strength,suitable porous network,superior electrical conductivity,and good biocompatibility.In vitro results revealed that GF/hydrogel scaffold could obviously accelerate proliferation of Schwann cells.Moreover,in vivo experiments demonstrated that ADSCs-loaded GF/hydrogel scaffold significantly promoted the recovery of DPNI and inhibited the atrophy of targeted muscles,thus providing a novel and attractive therapeutic approach for DPNI patients.展开更多
目的探讨酰胺质子转移加权(amide proton transfer weighted,APTw)与动态对比增强磁共振成像(dynamic contrast enhanced MRI,DCE-MRI)序列评估宫颈癌神经周围侵犯(perineural invasion,PNI)的价值。材料与方法回顾性分析36例行盆腔3.0 ...目的探讨酰胺质子转移加权(amide proton transfer weighted,APTw)与动态对比增强磁共振成像(dynamic contrast enhanced MRI,DCE-MRI)序列评估宫颈癌神经周围侵犯(perineural invasion,PNI)的价值。材料与方法回顾性分析36例行盆腔3.0 T MRI检查(包括APTw、DCE-MRI序列)且手术病理证实为宫颈癌的患者病例及影像资料,其中有PNI(PNI组)12例,无PNI(NPNI组)24例。由两位观察者分别测量病灶的APT值与DCE-MRI定量参数值,包括容积转移分数(volume transfer constant,K^(trans))、速率常数(exchange rate between EES and blood plasma,K_(ep))、血管外细胞外间隙容积分数(extravascular volume fraction,V_(e))以及血浆容积分数(capillary plasma volume,V_(p))。采用组内相关系数(intra-class correlation coefficient,ICC)检验2位观察者对各参数值测量结果的一致性;采用Kolmogorov-Smirov检验数据是否符合正态分布,通过两独立样本t检验或Mann-Whitney U检验比较两组间参数值的差异,采用受试者工作特征(receiver Operating Characteristic,ROC)曲线评估有差异参数诊断PNI效能,获得相应的曲线下面积(area under the curve,AUC)、阈值、敏感度和特异度。采用二元logistic回归计算有差异参数的联合诊断效能,DeLong检验进行各参数和联合参数AUC比较,Spearman相关分析检测APT值和有差异DCE-MRI参数间的相关性。结果两位观察者测得的APT值及K^(trans)值、K_(ep)值、V_(e)值、V_(p)值结果一致性良好,ICC均>0.75。两组间的APT值和V_(p)值差异有统计学意义(P<0.05),K^(trans)、K_(ep)、V_(e)差异无统计学意义(P>0.05)。PNI组的APT值(2.89%±0.72%)和V_(p)值[7.80×10^(-3)(6.80×10^(-3),1.14×10^(-2))]均大于NPNI组[APT值2.31%±0.71%;V_(p)值4.19×10^(-3)(2.04×10^(-3),7.35×10^(-3))]。评估宫颈癌PNI时,APT值和V_(p)值的AUC分别为0.717、0.785,阈值分别为2.7%及6.46×10^(-3),敏感度及特异度分别为66.7%及75.0%、83.3%及75.0%;APT值联合V_(p)值后的AUC为0.792,APT值、V_(p)值与两者联合后的AUC之间差异无统计学意义(P>0.05)。APT值与V_(p)值无相关性(r=0.219,P=0.198)。结论APTw序列及DCE-MRI的定量参数均能有效预测宫颈癌PNI,具有一定临床应用价值。展开更多
目的:探讨MR放射组学预测直肠腺癌患者神经周围侵犯(PNI)的价值。方法:将2016年12月-2019年7月经本院全直肠系膜切除术术后病理证实为直肠腺癌的110例患者纳入本研究,所有患者均行高分辨率直肠MR扫描,在直肠病灶高分辨率横轴面T 2WI上...目的:探讨MR放射组学预测直肠腺癌患者神经周围侵犯(PNI)的价值。方法:将2016年12月-2019年7月经本院全直肠系膜切除术术后病理证实为直肠腺癌的110例患者纳入本研究,所有患者均行高分辨率直肠MR扫描,在直肠病灶高分辨率横轴面T 2WI上勾画病灶,运用AK软件提取396放射组学特征,患者按13:7的比例分为训练集(72例)和验证集(38例),以术后病理为金标准,采用最大相关最小冗余的方式对组学特征进行初步筛选,保留10个有最大预测效能的特征,然后进行LASSO回归分析,构建影像组学模型。采用ROC曲线分析评估模型预测PNI的效能,决策曲线分析法评估模型的临床价值。结果:训练集72例,验证集38例,两组年龄(65.6±9.7岁vs 64.4±9.8岁,t=0.363,P=0.719)、性别(男∶女为50∶22 vs 26∶12,χ2=0.012,P=0.912)、CEA[2.86(1.49,4.84)ng/mL vs 3.20(2.14,6.37)ng/mL,Z=-0.0990,P=0.322]差异无统计学意义。术后病理提示有PNI的患者24例,无PNI的患者86例,PNI组和无PNI组年龄(63.9±12.1岁vs 64.9±9.0岁,t=0.423,P=0.673)、性别(男∶女,57∶27 vs 9∶7,χ2=0.253,P=0.615)、CEA[3.20(1.94,4.88)ng/mL vs 2.90(1.68,6.12)ng/mL,Z=-0.004,P=0.997]差异无统计学意义,训练集中最终选取了9个MR放射组学参数,根据公式计算Radscore,构建出最佳预测模型,OR值为5.54,P<0.05,训练集曲线下面积约0.79,验证集曲线下面积约0.76。决策曲线显示阈值在0.2~1较大的范围内,该模型净受益率比简单模型高。结论:采用MR放射组学构建的模型可较好预测直肠腺癌神经周围侵犯。展开更多
外周神经电刺激可用于运动康复和慢性神经痛治疗,但目前具有空间选择性的无损刺激仍是一个有待解决的问题。提出一种基于时间相干(TI)电场的外周神经选择性无损电刺激方法,对大鼠坐骨神经进行实验,在其大腿腹侧与背侧皮肤上以平行于神...外周神经电刺激可用于运动康复和慢性神经痛治疗,但目前具有空间选择性的无损刺激仍是一个有待解决的问题。提出一种基于时间相干(TI)电场的外周神经选择性无损电刺激方法,对大鼠坐骨神经进行实验,在其大腿腹侧与背侧皮肤上以平行于神经的方向布置刺激电极,通过相干电场扫描,将TI刺激峰值定位到神经上进行选择性刺激。结果表明,该方法可以在预先不知道神经确切位置的情况下通过扫描得出将刺激电场作用到神经的最佳电参数,从而实现对神经的选择性无损刺激,而且在刺激作用点不变的前提下实现刺激强度的控制。在此基础上研究TI电场对大鼠坐骨神经的刺激阈值IT,测量固定频差Δf=0.5 Hz(n=12),改变频率f=1~6 k Hz与固定f=5 k Hz(n=11),改变频差Δf=0.5~10 Hz下的I_T,并将其和等幅k Hz电场(n=7)的I_T进行比较。结果表明,等幅k Hz电场的I_T显著高于TI电场(P<0.05),而且不同频率f下的I_T也有显著性差异(P<0.05),而不同频差Δf下的I_T却没有显著性差异(P>0.05),说明TI电流对大鼠坐骨神经的I_T受f影响而不受Δf影响,且刺激阈值IT与频率f成正比关系。展开更多
文摘Therapies such as direct tension-free microsurgical repair or transplantation of a nerve autograft,are nowadays used to treat traumatic peripheral nerve injuries（PNI）,focused on the enhancement of the intrinsic regenerative potential of injured axons.However,these therapies fail to recreate the suitable cellular and molecular microenvironment of peripheral nerve repair and in some cases,the functional recovery of nerve injuries is incomplete.Thus,new biomedical engineering strategies based on tissue engineering approaches through molecular intervention and scaffolding offer promising outcomes on the field.In this sense,evidence is accumulating in both,preclinical and clinical settings,indicating that platelet-rich plasma products,and fibrin scaffold obtained from this technology,hold an important therapeutic potential as a neuroprotective,neurogenic and neuroinflammatory therapeutic modulator system,as well as enhancing the sensory and motor functional nerve muscle unit recovery.
文摘Each year approximately 360,000 people in the United States suffer a peripheral nerve injury （PNI）, which is a leading source of lifelong disability （Kelsey et al., 1997; Noble et al., 1998）. The most frequent cause of PNIs is motor vehicle accidents, while gunshot wounds, stabbings, and birth trauma are also common factors. Patients suffering from disabilities as a result of their PNIs are also burdensome to the healthcare system, with aver- age hospital stays of 28 days each year （Kelsey et al., 1997; Noble et al., 1998）.
基金supported by grants from the National Program on Key Basic Research Project of China(973 Program),No.2014CB542200Program for Innovative Research Team in University of Ministry of Education of China,No.IRT1201+1 种基金the National Natural Science Foundation of China,No.31271284,31171150,81171146,30971526,31100860,31040043Program for New Century Excellent Talents in University of Ministry of Education of China,No.BMU20110270
文摘In China, there are approximately 20 million people suffering from peripheral nerve injury and this number is increasing at a rate of 2 million per year. These patients cannot live or work independently and are a heavy responsibility on both family and society because of extreme disability and dysfunction caused by peripheral nerve injury （PNI）. Thus, repair of PNI has become a major public health issue in China.
文摘The peripheral nervous system （PNS） is composed of the nerves and ganglia outside of the brain and spinal cord whose primary function is to connect the central nervous system to the limbs and organs. A peripheral nerve injury （PNI） is damage to the nerves and/or its surrounding tissue. These injuries can affect up to 5% of patients that are hospitalized for trauma （Taylor et al., 2008） and over 50,000 surgical repair procedures are performed annually in the United States alone （Evans, 2001）.
文摘Who drew the borders between central and peripheral nervous sys tem？ A complex question but a simple answer. Human anatomy and clinical neurology need to differentiate peripheral nerves from central nervous system （CNS）, peripheral or central disorders, respectively. However, there are no anatomical and functional clefts between peripheral axons and central synaps- es. There is a direct continuity from the periphery to the center, from the receptor to the sensory neuron, from the spinal motor neuron to the muscle, just the neuromuscular junction.
文摘Peripheral nerve injuries （PNI） are a major clinical prob- lem. In general, PNI results from motor vehicle accidents, lacerations with sharp objects, penetrating trauma （gunshot wounds） and stretching or crushing trauma and fractures. It is estimated that PNI occur in 2.8% of trauma patients and this number reaches 5% if plexus and root lesions are in- cluded. However, due to lack of recent epidemiological stud- ies, these data probably underestimate the actual number of nerve injuries
文摘Objective： To explore the clinical value of the radical nerve dissection （RND） for the carcinoma of head of pancreas （CHP）. Methods： The clinical and pathological data of 30 CHP patients who underwent RND in our hospital were retrospectively analyzed, with an attempt to explore the safety and short-term efficacy of this procedure. Results： Among these 30 patients, the operative time was （351±61） rain, the intra-operative blood loss was 350 （range, 300-600） mL, and the grades B and C pancreatic fistula was 23.33%. During the follow-up （range, 2-30 months; median： 17 months）, the 1-year survival rate was 63.33% and the 1-year disease-free survival rate was 56.67%. Among the 23 patients （76.66%） with positive extra-pancreatic perineural invasion （PNI）, the 1-year case- fatality rate was 34.78%, which was not significantly different from that （28.57%） of patients with negative PNI （P=0.760）. Conclusions： Our results suggested potential advantages of RND in the fields of surgery-associated risk and prognosis compared with the Whipple operation in the treatment of CHP. Due to the low sample size of this study, further well-designed research of large sample size is needed.
基金This study is financially supported by the National Natural Science Foundation of China(Nos.81971758,51890892,81971712,81870346,and 81700432)the Natural Science Foundation of Shanghai Science and Technology Committee(No.20ZR1431600)+7 种基金This research is also supported by the National Natural Science Foundation of China(No.11761161004)Z.L.acknowledge supports by the National Natural Science Foundation of China-Research Grants Council Joint Research Scheme(Nos.11761161004 and N_HKUST607/17)the IER foundation(No.HT-JD-CXY-201907)“International science and technology cooperation projects”of Science and Technological Bureau of Guangzhou Huangpu District(No.2019GH06)Guangdong Science and Technology Department(No.2020A0505090003)Research Fund of Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology(No.2020B1212030010)Technical assistance from the Materials Characterization and Preparation Facilities of The Hong Kong University Of Science And Technology is greatly appreciatedWe also acknowledge the support of Guangdong Provincial Key Laboratory Program(No.2021B1212040001)from the Department of Science and Technology of Guangdong Province.
文摘The functional recovery of peripheral nerve injury(PNI)is unsatisfactory,whereas diabetes mellitus(DM)and its related complications further attenuate the restoration of diabetic PNI(DPNI).Adipose-derived stem cells(ADSCs)are promising candidates for treatment of DPNI due to their abundant source,excellent differentiation and paracrine ability.Our results showed that ADSCs remarkably enhanced the proliferation and migration of Schwann cells and endothelial cells,and tube formation.Mechanistically,ADSCs could regulate Nrf2/HO-1,NF-κB and PI3K/AKT/mTOR signaling pathways,showing multiple functions in reducing oxidative stress and inflammation,and regulating cell metabolism,growth,survival,proliferation,angiogenesis,differentiation of Schwann cell and myelin formation.In current study,novel graphene foam(GF)/hydrogel-based scaffold was developed to deliver ADSCs for treatment of DPNI.GF/hydrogel scaffold exhibited excellent mechanical strength,suitable porous network,superior electrical conductivity,and good biocompatibility.In vitro results revealed that GF/hydrogel scaffold could obviously accelerate proliferation of Schwann cells.Moreover,in vivo experiments demonstrated that ADSCs-loaded GF/hydrogel scaffold significantly promoted the recovery of DPNI and inhibited the atrophy of targeted muscles,thus providing a novel and attractive therapeutic approach for DPNI patients.
文摘目的探讨酰胺质子转移加权(amide proton transfer weighted,APTw)与动态对比增强磁共振成像(dynamic contrast enhanced MRI,DCE-MRI)序列评估宫颈癌神经周围侵犯(perineural invasion,PNI)的价值。材料与方法回顾性分析36例行盆腔3.0 T MRI检查(包括APTw、DCE-MRI序列)且手术病理证实为宫颈癌的患者病例及影像资料,其中有PNI(PNI组)12例,无PNI(NPNI组)24例。由两位观察者分别测量病灶的APT值与DCE-MRI定量参数值,包括容积转移分数(volume transfer constant,K^(trans))、速率常数(exchange rate between EES and blood plasma,K_(ep))、血管外细胞外间隙容积分数(extravascular volume fraction,V_(e))以及血浆容积分数(capillary plasma volume,V_(p))。采用组内相关系数(intra-class correlation coefficient,ICC)检验2位观察者对各参数值测量结果的一致性;采用Kolmogorov-Smirov检验数据是否符合正态分布,通过两独立样本t检验或Mann-Whitney U检验比较两组间参数值的差异,采用受试者工作特征(receiver Operating Characteristic,ROC)曲线评估有差异参数诊断PNI效能,获得相应的曲线下面积(area under the curve,AUC)、阈值、敏感度和特异度。采用二元logistic回归计算有差异参数的联合诊断效能,DeLong检验进行各参数和联合参数AUC比较,Spearman相关分析检测APT值和有差异DCE-MRI参数间的相关性。结果两位观察者测得的APT值及K^(trans)值、K_(ep)值、V_(e)值、V_(p)值结果一致性良好,ICC均>0.75。两组间的APT值和V_(p)值差异有统计学意义(P<0.05),K^(trans)、K_(ep)、V_(e)差异无统计学意义(P>0.05)。PNI组的APT值(2.89%±0.72%)和V_(p)值[7.80×10^(-3)(6.80×10^(-3),1.14×10^(-2))]均大于NPNI组[APT值2.31%±0.71%;V_(p)值4.19×10^(-3)(2.04×10^(-3),7.35×10^(-3))]。评估宫颈癌PNI时,APT值和V_(p)值的AUC分别为0.717、0.785,阈值分别为2.7%及6.46×10^(-3),敏感度及特异度分别为66.7%及75.0%、83.3%及75.0%;APT值联合V_(p)值后的AUC为0.792,APT值、V_(p)值与两者联合后的AUC之间差异无统计学意义(P>0.05)。APT值与V_(p)值无相关性(r=0.219,P=0.198)。结论APTw序列及DCE-MRI的定量参数均能有效预测宫颈癌PNI,具有一定临床应用价值。
文摘目的:探讨MR放射组学预测直肠腺癌患者神经周围侵犯(PNI)的价值。方法:将2016年12月-2019年7月经本院全直肠系膜切除术术后病理证实为直肠腺癌的110例患者纳入本研究,所有患者均行高分辨率直肠MR扫描,在直肠病灶高分辨率横轴面T 2WI上勾画病灶,运用AK软件提取396放射组学特征,患者按13:7的比例分为训练集(72例)和验证集(38例),以术后病理为金标准,采用最大相关最小冗余的方式对组学特征进行初步筛选,保留10个有最大预测效能的特征,然后进行LASSO回归分析,构建影像组学模型。采用ROC曲线分析评估模型预测PNI的效能,决策曲线分析法评估模型的临床价值。结果:训练集72例,验证集38例,两组年龄(65.6±9.7岁vs 64.4±9.8岁,t=0.363,P=0.719)、性别(男∶女为50∶22 vs 26∶12,χ2=0.012,P=0.912)、CEA[2.86(1.49,4.84)ng/mL vs 3.20(2.14,6.37)ng/mL,Z=-0.0990,P=0.322]差异无统计学意义。术后病理提示有PNI的患者24例,无PNI的患者86例,PNI组和无PNI组年龄(63.9±12.1岁vs 64.9±9.0岁,t=0.423,P=0.673)、性别(男∶女,57∶27 vs 9∶7,χ2=0.253,P=0.615)、CEA[3.20(1.94,4.88)ng/mL vs 2.90(1.68,6.12)ng/mL,Z=-0.004,P=0.997]差异无统计学意义,训练集中最终选取了9个MR放射组学参数,根据公式计算Radscore,构建出最佳预测模型,OR值为5.54,P<0.05,训练集曲线下面积约0.79,验证集曲线下面积约0.76。决策曲线显示阈值在0.2~1较大的范围内,该模型净受益率比简单模型高。结论:采用MR放射组学构建的模型可较好预测直肠腺癌神经周围侵犯。
文摘外周神经电刺激可用于运动康复和慢性神经痛治疗,但目前具有空间选择性的无损刺激仍是一个有待解决的问题。提出一种基于时间相干(TI)电场的外周神经选择性无损电刺激方法,对大鼠坐骨神经进行实验,在其大腿腹侧与背侧皮肤上以平行于神经的方向布置刺激电极,通过相干电场扫描,将TI刺激峰值定位到神经上进行选择性刺激。结果表明,该方法可以在预先不知道神经确切位置的情况下通过扫描得出将刺激电场作用到神经的最佳电参数,从而实现对神经的选择性无损刺激,而且在刺激作用点不变的前提下实现刺激强度的控制。在此基础上研究TI电场对大鼠坐骨神经的刺激阈值IT,测量固定频差Δf=0.5 Hz(n=12),改变频率f=1~6 k Hz与固定f=5 k Hz(n=11),改变频差Δf=0.5~10 Hz下的I_T,并将其和等幅k Hz电场(n=7)的I_T进行比较。结果表明,等幅k Hz电场的I_T显著高于TI电场(P<0.05),而且不同频率f下的I_T也有显著性差异(P<0.05),而不同频差Δf下的I_T却没有显著性差异(P>0.05),说明TI电流对大鼠坐骨神经的I_T受f影响而不受Δf影响,且刺激阈值IT与频率f成正比关系。
文摘神经生长因子(never growth factor,NGF)可促进损伤外周神经的修复并加速轴突和髓鞘的再生,但对外周神经损伤前期作用的研究报道较少。本研究主要探究在损伤外周神经前期,NGF能否加速施旺细胞(Schwann cells,SCs)对髓鞘碎片的清除及其调控机制。将坐骨神经损伤的Wistar雄性大鼠连续5 d给予NGF治疗,并运用分子生物学检测手段分析损伤坐骨神经内部髓鞘碎片的清除,细胞的凋亡及内质网应激(endoplasmic reticulum stress,ERS)的表达和变化。免疫荧光分析结果显示,与模型组相比,NGF给药组显著加速髓鞘碎片的清除,并促进SCs的增殖(46.33±5.68 vs.66.69±8.76,P<0.05 for MPZ;47.58±4.52 vs.37.69±2.50,P<0.01for GFAP)。TUNEL免疫组化证实,NGF可有效抑制SCs的凋亡(25±4 vs.37±6,P<0.05),Western印迹结果显示,模型组坐骨神经内部内质网应激水平被过度激活,给予NGF治疗后,相关蛋白质表达被逆转(1.03±0.03 vs.1.24±0.07,P<0.01 for PDI;1.16±0.16 vs.1.48±0.10,P<0.05 for GRP-78;1.33±0.11 vs.1.76±0.17,P<0.01 for Caspase-12;1.01±0.05vs.1.39±0.16,P<0.01 for CHOP)。上述结果证实,NGF可通过抑制内质网应激减少神经组织内细胞的凋亡,并加速髓鞘碎片的清除,促进外周神经损伤的修复。
