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101.
目的观察中药新复方参乌胶囊及其有效成分何首乌二苯乙烯苷对老年大鼠脊髓腰节段细胞凋亡及信号转导通路的影响。方法雄性SD大鼠,分为青年组(6月龄)、老年组(24月龄)、老年+参乌胶囊小剂量(0.8 g/kg)、参乌胶囊大剂量(1.6 g/kg)、二苯乙烯苷小剂量(0.03 g/kg)、二苯乙烯苷大剂量(0.06 g/kg)组。应用Western blot方法检测大鼠脊髓腰节段Bax、Bcl-2及磷酸化cAMP反应元件结合蛋白(p-CREB)的变化及药物的干预作用。结果与6月龄青年大鼠相比,24月龄老年大鼠脊髓腰节段凋亡促进因子Bax的表达增加,凋亡抑制因子Bcl-2的表达减少,神经元存活信号转导通路中p-CREB的表达降低。参乌胶囊和二苯乙烯苷分别灌胃给药3个月能够抑制老年大鼠脊髓腰节段内BAX的表达,增强Bcl-2表达。参乌胶囊还能够上调p-CREB表达。结论乌胶囊及二苯乙烯苷能够改善老年大鼠脊髓腰节段Bax、Bcl-2和p-CREB的变化,提示该药可能具有延缓脊髓衰老的作用。  相似文献   
102.
Spinal muscular atrophy (SMA) is a recessive neuromuscular disorder caused by loss of the SMN1 gene. The clinical distinction between SMA type I to IV reflects different age of onset and disease severity. SMN2, a nearly identical copy gene of SMN1, produces only 10% of full-length SMN RNA/protein and is an excellent target for a potential therapy. Several clinical trials with drugs that increase the SMN2 expression such as valproic acid and phenylbutyrate are in progress. Solid natural history data for SMA are crucial to enable a correlation between genotype and phenotype as well as the outcome of therapy. We provide genotypic and phenotypic data from 115 SMA patients with type IIIa (age of onset <3 years), type IIIb (age of onset >3 years) and rare type IV (onset >30 years). While 62% of type IIIa patients carry two or three SMN2 copies, 65% of type IIIb patients carry four or five SMN2 copies. Three type IV SMA patients had four and one had six SMN2 copies. Our data support the disease-modifying role of SMN2 leading to later onset and a better prognosis. A statistically significant correlation for ≥4 SMN2 copies with SMA type IIIb or a milder phenotype suggests that SMN2 copy number can be used as a clinical prognostic indicator in SMA patients. The additional case of a foetus with homozygous SMN1 deletion and postnatal measurement of five SMN2 copies illustrates the role of genotypic information in making informed decisions on the management and therapy of such patients.Database: SMN1—OMIM: 600354; GeneBank: U18423, SMN2—OMIM: 601627: GeneBank: NM_022875  相似文献   
103.
Bone fractures were analyzed from skeletal remains of 861 adult individuals from six cemeteries dating to the Late Medieval period in Serbia. Results of the study were compared to other cemetery populations (635 individual skeletons) of the same date and region in an attempt to understand fracture patterns. The association of types of fractures and their prevalence with sex, age at death, cemetery site, and information deriving from historical sources are discussed. Results showed that the long bone fracture frequency was 0.7%, and the majority of the fractures were the result of direct force. This rate is similar to some studies of contemporary British skeletal samples. However, it is much lower than for some other Old World sites. Cranial vault fractures had a rate of 6.7%, and of the facial skeleton, 1.3%; the frontal bone was the most affected of bones of the cranial vault. Injuries were more common on the upper extremities (0.8%) compared to the lower (0.6%). However, the fibula was the most fractured bone (2.8%), followed by the ulna (2.4%). This pattern is similar to three of six Late Medieval urban sites in Britain. These findings suggest that this rural community was exposed to a low risk of trauma, probably related mostly to accidents sustained during farming, and rarely to interpersonal violence.  相似文献   
104.
Rho-associated Kinase (ROCK) has been identified as an important regulator of proliferation and cell cycle progression in a number of cell types. Although its effects on astrocyte proliferation have not been well characterized, ROCK has been reported to play important roles in gap junction formation, morphology, and migration of astrocytes. In the present study, our aim was to investigate the effect of ROCK inhibition by [(+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl) cyclohexanecarboxamide dihydrochloride] (Y27632) on proliferation and DNA synthesis in cultured astrocytes from rat spinal cord and the possible mechanism involved. Western blots showed that treatment of astrocytes with Y27632 increased their expression of cyclin D1, CDK4, and cyclin E, thereby causing cell cycle progression. Furthermore, Y27632-induced astrocyte proliferation was mediated through the extracellular-signal-regulated kinase signaling cascade. These results indicate the importance of ROCK in astrocyte proliferation.  相似文献   
105.
Lysophosphatidic acid (LPA) is a bioactive lipid that serves as an extracellular signaling molecule acting through cognate G protein-coupled receptors designated LPA(1-6) that mediate a wide range of both normal and pathological effects. Previously, LPA(1), a G(αi)-coupled receptor (which also couples to other G(α) proteins) to reduce cAMP, was shown to be essential for the initiation of neuropathic pain in the partial sciatic nerve ligation (PSNL) mouse model. Subsequent gene expression studies identified LPA(5), a G(α12/13)- and G(q)-coupled receptor that increases cAMP, in a subset of dorsal root ganglion neurons and also within neurons of the spinal cord dorsal horn in a pattern complementing, yet distinct from LPA(1), suggesting its possible involvement in neuropathic pain. We therefore generated an Lpar5 null mutant by targeted deletion followed by PSNL challenge. Homozygous null mutants did not show obvious base-line phenotypic defects. However, following PSNL, LPA(5)-deficient mice were protected from developing neuropathic pain. They also showed reduced phosphorylated cAMP response element-binding protein expression within neurons of the dorsal horn despite continued up-regulation of the characteristic pain-related markers Caα(2)δ(1) and glial fibrillary acidic protein, results that were distinct from those previously observed for LPA(1) deletion. These data expand the influences of LPA signaling in neuropathic pain through a second LPA receptor subtype, LPA(5), involving a mechanistically distinct downstream signaling pathway compared with LPA(1).  相似文献   
106.
Partial weight-bearing instructions are commonly given to orthopaedic patients and are an important part of post-injury and/or post-operative care. However, the ability of patients to comply with these instructions is poorly defined. Training methods for instructing these patients vary widely among institutions. Traditional methods of training include verbal instruction and use of a bathroom scale. Recent technological advances have created biofeedback devices capable of offering feedback to partial weight-bearing patients. Biofeedback devices have shown great promise in training patients to better comply with partial weight-bearing instructions. This review examines the background and significance of partial weight bearing and offers insights into current advances in training methods for partial weight-bearing patients.  相似文献   
107.
目的研究间充质干细胞—透明质酸—多聚赖氨酸复合物治疗脊髓损伤的可行性,评价其治疗效果并探讨其可能机制。方法从人骨髓中分离、培养人骨髓间充质干细胞(human bone marrow mesenchymal stem cell,hBMSC);制作大鼠脊髓半横断模型,按照实验分组分别将hBMSC、透明质酸-多聚赖氨酸(hyaluronic acid-poly-L-lysine,HA-PLL)、hBMSC-HA-PLL复合物注入损伤区域,单纯损伤组作为对照。术后按照不同时间点评价损伤和移植后的大鼠运动功能。8周后杀死大鼠,观察不同移植组体内轴突和血管生长的情况,对不同细胞、材料及复合物移植对大鼠脊髓损伤修复效果进行评估。结果 hBMSC移植组和hBMSC-HA-PLL移植组的大鼠运动功能的改善显著好于单纯损伤及HA-PLL移植组。电镜结果证实复合物移植组可显著促进轴突和血管生长,新生的轴突和血管结构较为完整。结论 hBMSC具有促进神经功能恢复的作用,将其与HA-PLL相结合,可以促进大鼠脊髓损伤修复,其机制可能包括材料框架作用和hBMSC在体内对大鼠神经细胞的营养作用以及促进微血管的生成。  相似文献   
108.
目的 评价细胞外信号调节激酶 (ERK)传导通路对低压灌注缺血后处理兔缺血/再灌注损伤脊髓的保护作用及机制.方法 84只日本大耳白兔随机分为7组,分别为C组(对照组,不给予缺血后处理)、PB组(缺血后处理组)、D、PD1、PD3、PD9组分别于腹主动脉开放前1min鞘内注射DMSO 20μl、PD98059 1μg(20μl)、PD98059 3μg(20μl)、PD98059 9μg(20μl)之后进行缺血后处理及PD组(腹主动脉开放前1min鞘内注射PD98059 3μg(20μl),之后不行缺血后处理).分别于再灌注1、3、7、28d时采用Tarlov评分评价后肢运动功能.每组于再灌注1d时处死6只动物,取L3~5节段脊髓组织,采用Western blot技术测定p-ERK1/2 及Bcl-2,Bax蛋白表达.结果 1、3、7、28d,PB组Tarlov评分明显高于其它各组(P<0.05),缺血后处理可以明显上调p-ERK1/2及凋亡抑制基因Bcl-2的表达,下调凋亡促进基因Bax的表达(P<0.05),而这些调节作用可以被ERK1/2阻断剂PD98059抑制.结论 p-ERK1/2在低压灌注缺血后处理对缺血再灌注损伤脊髓的保护中起重要作用.  相似文献   
109.
目的:探讨经皮椎体后凸成形术(PKP)治疗多节段骨质疏松性椎体压缩性骨折(OVCF)的疗效和安全性。方法:应用PKP治疗37例共112节胸腰椎多节段骨质疏松性椎体压缩骨折,分析患者术前、术中、术后的临床及影像学资料,采用模拟视觉评分(VAS)及Oswesty功能障碍指数(ODI)评价术前、术后疼痛缓解及日常活动功能恢复情况。结果:13例一次手术完成1节椎体,12例一次手术完成2~3节段椎体,12例两次手术完成3~4个节段椎体。1例术中出现一过性血压降低和呛咳。VAS评分术前为(8.55±1.22)分,术后1周为(2.12±1.09)分,术后3个月为(2.01±1.07)分;ODI值术前为83.02±11.14,术后1周为25.23±7.17,术后3个月为27.45±9.67,疼痛缓解及日常活动功能恢复明显。结论:初步的临床结果显示PKP是多节段骨质疏松性椎体压缩性骨折的有效治疗方法,单椎体信号改变者治疗效果好于多椎体信号改变者。多椎体信号改变者只选择第一责任椎的单节段PKP可能获得更好的效果;多节段患者同时选择第一和第二责任椎一次完成PKP术效果可能好于分次完成。一次治疗多椎体病变更为经济、适用。  相似文献   
110.
目的:探讨磁共振(MR)扩散张量成像(DTI)作为定量分析方法,对脊髓型颈椎病(CSM)脊髓早期损伤诊断的应用价值.方法:选择45例经临床及影像诊断为脊髓型颈椎病患者,颈椎常规MRI检查显示脊髓内无异常信号,使用单次激发自旋回波平面(SE-EPI)序列,进行DTI扫描.测量压迫部位脊髓的ADC值及FA值作为病例组,选择病变上或下方两个节段以上未受压正常脊髓作为正常对照组,测量其ADC值及FA值.分析病例组与对照组间ADC及FA值差别,计算ADC值及FA值诊断脊髓损伤的敏感性.结果:所有脊髓型颈椎病患者经DTI检查均可得到ADC图及FA图,经图像后处理,脊髓显示清晰,图像无变形及伪影.3例脊髓型颈椎病患者ADC值降低,42例脊髓型颈椎病患者ADC值增高,平均ADC值为(1.388± 0.149)x 10-3 mm2/s.44名脊髓型颈椎病患者FA值降低,1名脊髓型颈椎病患者FA值增高,平均FA值为0.476±0.085,受压处脊髓平均ADC值升高,平均FA值下降,与正常值比较差别有统计学意义.ADC值诊断的敏感性为93.33%,FA值诊断的敏感性为97.78%.结论:DTI与常规MR比较,能早期而准确地诊断脊髓型颈椎病脊髓早期损伤.  相似文献   
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