PPARγ激动剂对大鼠局灶性脑缺血再灌注损伤后IL-1β、IL-6和TNF-α含量的影响

目的观察PPARγ激动剂吡格列酮对大鼠局灶性脑缺血再灌注损伤(I/R)的保护作用,并对其作用机制进行初步探讨。方法复制大鼠大脑中动脉阻断再灌注模型(MCAO/R),分别采用TTC染色法、神经功能评分法观察PPARγ激动剂对大鼠脑梗死体积和行为学评分的影响,同时观察PPARγ激动剂对脑组织内白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)含量的影响。结果PPARγ激动剂能够减少I/R大鼠脑梗死体积和行为学评分,降低脑组织中IL-1β、IL-6和TNF-α的含量(P<0.05)。结论PPARγ激动剂对大鼠脑缺血再灌注损伤有一定保护作用,其作用机制与降低脑组织中IL-1β、IL-6和TNF-α含量有关。     

国产降纤酶对缺血/再灌注大鼠脑组织TNF-α及IL-1β mRNA表达的影响

目的观察国产降纤酶对局灶性缺血/再灌注不同时程大鼠脑组织TNF-αmRNA和IL-1βmRNA表达的影响,探讨降纤酶减轻脑缺血/再灌注损伤的可能机制。方法应用RT-PCR技术,分析降纤酶治疗的脑缺血3h/再灌注3h、6h、24h和72h大鼠脑组织TNF-αmRNA和IL-1βmRNA表达水平。结果缺血3h/再灌注72h,降纤酶治疗组动物缺血侧脑组织TNF-αmRNA的表达水平明显低于生理盐水对照组(P<0.01);降纤酶治疗组动物缺血侧脑组织IL-1βmRNA的表达水平在缺血3h/再灌注3h和6h时显著低于生理盐水组(P<0.05)。结论降纤酶减轻脑的缺血/再灌注损伤与下调细胞因子TNF-αmRNA和IL-1βmRNA的表达有一定的关系。     

动脉移植BMSCs对大鼠缺血再灌注损伤脊髓CNTF和STAT3的影响

目的探讨肾下腹主动脉移植骨髓间充质干细胞(BMSCs)对大鼠缺血再灌注损伤脊髓CNTF和STAT3的影响及对损伤脊髓功能恢复的作用。方法 24只成年SD雌性大鼠随机分为假手术组、对照组及移植组3组,每组8只。术后对大鼠进行后肢神经行为学评分和运动诱发电位检测,采用RT-PCR、Western blot检测大鼠缺血节段脊髓内CNTF和STAT3的表达变化。结果与假手术组比较,对照组和移植组BBB评分于术后0 d、5 d、10 d、15 d显著降低(P<0.01),MEP潜伏期延长(P<0.01)、波幅减小(P<0.01),脊髓CNTF和STAT3 mRNA和蛋白表达增加(P<0.01);与对照组比较,移植组BBB评分于术后5¹5 d增高(P<0.01),MEP潜伏期缩短(P<0.01)、波幅增加(P<0.01),CNTF和STAT3 mRNA和蛋白表达增加(P<0.01)。结论肾下腹主动脉移植BMSC可能通过增加损伤脊髓局部CNTF和STAT-3表达促进脊髓缺血再灌注损伤大鼠后肢功能恢复。     

白藜芦醇对大鼠脊髓缺血再灌注损伤组织中TNF-α和IL-6水平的影响

目的探讨白藜芦醇对大鼠脊髓缺血再灌注损伤组织中肿瘤坏死因子-α(TNF-α)和白介素-6(IL-6)的影响。方法健康Wistar大鼠48只,随机均分为假手术组、缺血再灌注损伤组、白藜芦醇50mg·kg-1组和白藜芦醇25mg·kg-1组,每组12只,采用腹主动脉缺血法制备大鼠脊髓缺血再灌注损伤模型,然后采用ELISA法检测各组大鼠脊髓组织中TNF-α和IL-6水平。结果白藜芦醇50mg·kg-1组和白藜芦醇25mg·kg-1组大鼠脊髓组织中TNF-α和IL-6水平均低于缺血再灌注损伤组,差异有统计学意义(P0.05)。白藜芦醇50mg·kg-1组大鼠脊髓组织中TNF-α和IL-6水平低于白藜芦醇25mg·kg-1组,差异有统计学意义(P0.05)。结论白藜芦醇能够降低脊髓缺血再灌注损伤组织中TNF-α和IL-6水平,改善机体的免疫功能,进而减轻脊髓组织的缺血再灌注损伤。     

重症肌无力患者外周血Th17细胞及其相关细胞因子表达研究

目的研究重症肌无力患者外周血辅助性T细胞17(Th17)及其相关细胞因子水平,探讨其与血清抗乙酰胆碱受体(AChR)抗体水平的相关性。方法纳入2016年9月至2017年12月共30例初诊重症肌无力患者,眼肌型(OMG) 16例、全身型(GMG) 14例。流式细胞术检测外周血单个核细胞Th17细胞比例,实时定量聚合酶链反应检测Th17细胞标志性细胞因子白细胞介素-17A(IL-17A)及其相关转录因子维A酸相关孤儿受体γ(RORγ)mRNA水平,酶联免疫吸附试验检测血浆IL-17A、IL-6、IL-23和抗AChR抗体水平。结果与正常对照组相比,GMG组和OMG组外周血Th17细胞比例(t=-3.312,P=0.002;t=-2.286,P=0.030)及其相关转录因子RORγmRNA表达水平(f=4.408,P=0.001;t=1.991,P=0.049),以及IL-17A水平(t=-4.282,P=0.004;t=-2.788,P=0.007)均高于正常对照组;GMG组IL-23水平亦高于正常对照组(t=-2.267,P=0.031)。重症肌无力患者外周血Th17细胞比例及血浆IL-17A水平与血清抗AChR抗体水平呈正相关(r=0.851,P=0.012;r=0.743,P=0.025)。结论重症肌无力患者外周血Th17细胞数目增加、血浆IL-17A表达水平升高,可能是导致重症肌无力发生与发展的重要原因,二者之间关系尚待进一步研究加以证实。     

小鼠局灶性脑缺血再灌注后IL-33及其受体的时程表达

目的检测白细胞介素-33(IL-33)及其膜受体ST2和可溶型受体sST2在小鼠局灶性脑缺血再灌注后不同时程的表达特征。方法利用线栓法闭塞大脑中动脉(MCAO)30 min诱导建立小鼠可逆性局灶性脑缺血再灌注损伤模型,通过半定量RT-PCR检测脑缺血再灌注后6 h、24 h和3 d缺血脑组织中IL-33及其膜受体ST2、凋亡相关蛋白Caspase-8和Caspase-3的mRNA表达水平,并通过免疫组织化学染色观察了IL-33在不同缺血脑区(运动皮质、感觉皮质、海马和纹状体)的时程表达情况;ELISA法检测了小鼠MCAO模型再灌注后不同时间点血清中IL-33及其可溶型受体sST2的表达水平。结果 IL-33 mRNA在缺血后6 h和3 d表达减少,但在24 h无明显改变;凋亡相关蛋白Caspase-3和Caspase-8在缺血后3个时间点均显著增高,且Caspase-3在6 h和3 d的mRNA表达水平较24 h高;ST2 mRNA在缺血后6 h无减少,但在24 h和3 d有明显减少;除了MCAO 24 h组运动皮质和纹状体阳性染色增加外,IL-33阳性细胞数在缺血后不同时程各脑区均有不同程度减少;缺血后外周血中IL-33的表达量无明显升高或降低,而sST2的表达水平在缺血后6 h即已显著升高。结论脑缺血再灌注后IL-33/ST2信号通路被下调,其与sST2表达增多的效应发挥和神经元凋亡有关。     

IL-17、RORγt在实验性自身免疫性神经炎中的表达

目的 观察Th17型细胞因子IL-17和Th17细胞特异性转录因子维甲酸受体相关孤儿受体γ的胸腺异构体(RORγt) mRNA在实验性自身免疫性神经炎(EAN)模型中的表达,以探讨Th17细胞在EAN中的作用.方法 用P253-78aa肽段免疫Lewis大鼠,建立EAN模型,观察大鼠发病情况和组织病理改变,并检测淋巴细胞增殖反应,用RT-PCR技术检测IL-17和RORγt在大鼠发病高峰期脾脏、淋巴结和坐骨神经中的表达.结果 EAN组大鼠在第14-16天发病高峰期时平均临床评分为(7.5±1.2),病理学检查可见明显炎性细胞浸润,对P253-78aa的刺激产生强烈淋巴细胞增殖反应,与对照组相比,IL-17和RORγt mRNA在脾脏、淋巴结和坐骨神经中的表达均显著升高(P<0.001).结论 IL-17和RORγt表达上调与EAN的发病相关.     

过氧化物酶体增殖物激活受体γ激动剂对小鼠局灶性脑缺血再灌注损伤的保护作用

目的 探讨过氧化物酶体增殖物激活受体γ(pemxisome proliferator-activated receptor gamma,PPARγ)激动剂对小鼠局灶性脑缺血再灌注损伤的保护作用及其机制.方法 制作小鼠大脑中动脉阻塞再灌注(MCAO/R)模型.分别采用3%氯化三苯四唑(TTC)染色法、神经功能缺损评分法观察PPARγ激动剂对小鼠脑梗死体积和行为学的影响;紫外分光光度法检测脑组织髓过氧化物酶(myeloperoxidase,MPO)活性;逆转录一聚合酶链反应、免疫组织化学、Western blot法观察炎性因子[细胞间黏附因子-1(ICAM-1)、白细胞介素-1β(IL-1β)、环氧合酶-2(COX-2)]mRNA和蛋白表达变化.结果 PPARγ激动剂能够显著降低小鼠脑梗死体积(mm3,29.1±6.6,模型组为57.8±9.7,t=5.980,P<0.01)和行为学评分(1.2±0.4,模型组3.3±0.8,t=5.812,P<0.01);能减轻缺血脑组织MPO活性(U/g,0.049±0.005,模型组0.083±0.008,t=5.904,P<0.01);减少缺血脑组织炎性因子ICAM·1、IL-1β和COX-2 mRNA表达和蛋白表达.结论 PPARγ激动剂对小鼠脑缺血再灌注损伤有一定的保护作用,其作用机制与减轻缺血脑组织的炎症反应有关.     

大鼠脊髓缺血再灌注损伤后血清内皮抑素和VEGF的相关性研究

目的探讨大鼠脊髓缺血再灌注损伤后血清中内皮抑素(endostatin,ES)和血管内皮生长因子(vascular endothelial growth factor,VEGF)的表达及相关性。方法采用Naslund腹主动脉阻断方法建立脊髓缺血动物模型。HE染色观察脊髓组织病理学变化,ELISA法分别检测脊髓缺血30min、90min再灌注后6h,2d,7d血清ES和VEGF水平;计算血清ES与VEGF含量的比值。结果与对照组相比,大鼠脊髓缺血30min再灌注后病理改变较轻,血清中VEGF、ES及e/V值无明显变化;缺血90min再灌注后神经元损伤较重,多数呈不可逆性坏死改变,ES[(107.750±9.692)ng·mL-1]及e/V值[(4.963±1.097)×103]均明显升高。结论大鼠脊髓缺血90min导致不可逆的脊髓损伤,血清e/V值的高低可能是影响缺血脊髓损伤程度和愈后的关键因素。     

Tongue/palate contact for the production of /s/ and /z/

Productions of /s/ and /z/ by ten adult speakers were investigated using the electropalatograph (EPG). The participants, ten speech researchers who spoke English as their first language, recorded productions of /s/ and /z/ in nonsense and real words. The maximum contact frame was used as the point of reference to compare tongue/palate contact for each production. Each speaker had alveolar contact, lateral bracing and most had a midline groove for both /s/ and /z/; however, the array of contacted electrodes was unique for each speaker. The groove widths and lengths ranged from 0-3 electrodes. There was significantly greater alveolar tongue/palate contact for /z/ compared to /s/ in word-initial position, but not in word-final position for the following measures: alveolar palatal contact, medial groove width, medial groove length. However, when measures of total palate contact and centre of gravity were considered, there was a complex interaction between the phonemes /s/ and /z/, coarticulation with the vowel, word position, and word context (real and nonsense words).     

Tongue/palate contact for the production of /s/ and /z/

Productions of /s/ and /z/ by ten adult speakers were investigated using the electropalatograph (EPG). The participants, ten speech researchers who spoke English as their first language, recorded productions of /s/ and /z/ in nonsense and real words. The maximum contact frame was used as the point of reference to compare tongue/palate contact for each production. Each speaker had alveolar contact, lateral bracing and most had a midline groove for both /s/ and /z/; however, the array of contacted electrodes was unique for each speaker. The groove widths and lengths ranged from 0–3 electrodes. There was significantly greater alveolar tongue/palate contact for /z/ compared to /s/ in word‐initial position, but not in word‐final position for the following measures: alveolar palatal contact, medial groove width, medial groove length. However, when measures of total palate contact and centre of gravity were considered, there was a complex interaction between the phonemes /s/ and /z/, coarticulation with the vowel, word position, and word context (real and nonsense words).     

Electropalatographic specification of Croatian fricatives /s/ and /z/

Electropalatographic specification of alveolar fricatives in Croatian is aimed at providing speech therapists with normative data about the range of acceptable productions of /s/ and /z/ in adult speakers of Croatian. Four variables were analysed: place of articulation, total contact, groove width and hold phase duration. Intra- and inter-speaker variability for each variable was analysed. Lingual palatal cues for voicing difference were also quantified and discussed. Results show that Croatian /s/ and /z/ are alveolar and not dental as previously reported. The comparison between the voiced and the voiceless fricative shows that durational measures provide the best differentiation. The voiceless counterpart is significantly longer. The difference between voiced and voiceless is also found in the total contact, with /z/ having more contact in the anterior four rows of electrodes, while /s/ has more contact in the posterior four rows of electrodes. This difference is also reflected in the anterior and the posterior groove widths. Possibilities of using these results as normative data for the diagnosis and treatment of atypical articulation of /s/ and /z/ are discussed.     

Rate and extent of functional reinnervation in fast-twitch and slow-twitch muscles of the dystrophic mouse (C57Bl6Jdy2jdy2j)

The extent of functional reinnervation of fast-twitch extensor digitorum longus muscle in dystrophic and normal mice was determined at various times after nerve transection. Functional reinnervation was assessed by measuring the twitch tension evoked by stimulation of the nerve central to the site of transection. In control mice aged 4 to 6 weeks at the time of denervation, complete reinnervation was observed after 6 weeks. In dystrophic mice of the same age reinnervation was clearly impaired. The ratio of functional innervation of the operated leg to that of the contralateral unoperated leg was only 0.62 after 6 weeks. In older dystrophic mice (4 to 6 months at the time of nerve transection) the reinnervation ratio was even lower, 0.43 after 12 weeks. Reinnervation of slow-twitch soleus muscle was assessed 8 weeks after denervation and was also found to be reduced in the older dystrophic animals. The extent of reinnervation was reflected in the measured values of muscle weight, twitch tension per unit wet weight, and twitch time course. The impairment of reinnervation of dystrophic muscle is consistent with, but not proof of, a neurogenic defect in murine muscular dystrophy.     

A comparative study of contractile responses in diaphragm muscles of normal and dystrophic (C57BL6Jdy2Jdy2J) mice

Potassium and caffeine contractures of isolated small bundles (100 to 200 μm diameter) of muscle fibers isolated from the diaphragm of normal and dystrophic ($\text{C57BL}\text{6J}\text{dy}{}^{\mathrm{2J}}\text{dy}{}^{\mathrm{2J}}$) mice were compared. In diaphragms of pathologic mice (3 to 5 months old) the resting potential, the characteristics of the twitch, and some histological examinations were typical of dystrophic muscles. The slopes of the relationships between the steady membrane potential and log [K]₀ were similar for the two types of cells. In 110 mM and 146 mM K there were no significant differences in the time course of the contractures and reduction in [Ca]₀ decreased the time to peak and the time constant of relaxation to the same extent; the relative efficiency of [Mg]₀ compared with [Ca]₀ was equivalent. Repriming of K contractures at different external calcium concentrations indicated that the normal diaphragm did not have any special advantage. The exposure of isolated strips to a solution containing caffeine resulted in a similar increase of the strength of the regularly evoked twitch responses. However, the contractures elicited by 1.25 to 20 mM caffeine showed a subsensitivity of the dystrophic diaphragm (K_mDys = 9.3 K_mN) and the rate of relaxation was significantly slower than in normal muscle (in 20 mM caffeine, 50% decay time for normal muscle was 25.2 ± 7.6 s and for dystrophic muscle 54.8 ± 11.2 s. THese results suggest an absence of major alterations in the mechanism of excitation-contraction coupling associated with dystrophy, except for a change in the specific element of the sarcoplasmic reticulum where caffeine acts.