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51.
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Jerzy Slowinski Jake Dominik Ryan J. Uitti Zeshan Ahmed Dennis D. Dickson Zbigniew K. Wszolek 《Neuropathology》2007,27(1):73-80
We present a case of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP‐17) harboring the N279K mutation in the MAPT gene from the family known as pallido‐ponto‐nigral degeneration (PPND). This 49‐year‐old man was followed for 17 years. He presented at age 41 years with left leg stiffness and en‐bloc turning. During the course of his illness he developed a constellation of symptoms including parkinsonism, pyramidal signs, vertical gaze palsy, dysphagia, dystonia, personality and cognitive dysfunction, weight loss and mutism. Gross neuropathological examination showed mild atrophy of the cerebral cortex, hippocampal formation, amygdala, thalamus, subthalamic nucleus and depigmentation of the substantia nigra. Microscopy revealed neuronal loss and gliosis in the same regions. Tau immunohistochemistry showed pretangles, numerous threads, grain‐like structures and oligodendroglial tau‐positive inclusions (“coiled bodies”). In the spinal cord the tau pathology was more abundant in gray than white matter. Pretangles and threads were present in the anterior and, to a lesser extent, in the posterior horns. FTDP‐17 should be suspected in patients with a history of familial parkinsonism combined with behavioral and cognitive changes, onset before age 65 years and an aggressive clinical course. 相似文献
53.
目的 观察异丙酚对 1 甲基 4 苯基 1,2 ,3 ,6 四氢吡啶 (1 methyl 4 phenyl 1,2 ,3 ,6 tetrahydropyridineMPTP)损伤的小鼠纹状体多巴胺神经元的影响以及可能的作用机制。方法 给予Propofol 10 0mg/ (kg·d)后注射MPTP 2 0mg/ (kg·d) ,用药 6d。 12d后分离纹状体应用高效液相 -电化学方法检测纹状体多巴胺、二羟基苯乙酸及高香草酸的含量水平 ,应用12 5I- β-CIT放射性配基和免疫组化的方法检测多巴胺转运蛋白的活性和黑质神经元的损伤情况。结果 异丙酚可增加MPTP模型鼠多巴胺及其代谢产物的含量 ,异丙酚处理组DA ,DOPAC ,HVA的含量分别为 (8.2 417± 1.692 ) μg/ g、(1.3 81± 0 .486) μg/g和 (1.63 3 9± 0 .5 73 ) μg/ g ,与MPTP损伤组比较 ,明显增加。异丙酚亦可抑制黑质酪氨酸羟化酶 (TH)阳性神经元的减少。MPTP组注射MPTP 6d后 ,纹状体DAT为 (5 .3 13± 0 .64 2 )与正常组 (6.992± 0 .5 48) μg/ g比较显著下降 (P <0 .0 1) ,P +M组纹状体DAT为 (6.5 65± 0 .40 5 ) ,明显高于MPTP组 (P <0 .0 1) ,即减轻纹状体内多巴胺转运蛋白密度下降。结论 异丙酚对MPTP损伤的DA神经元具有一定的保护作用 ,其保护作用可能与抑制多巴胺转运蛋白活性有关 相似文献
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W. Feleszko J. Jaworska R-D. Rha S. Steinhausen A. Avagyan A. Jaudszus B. Ahrens D. A. Groneberg U. Wahn E. Hamelmann 《Clinical and experimental allergy》2007,37(4):498-505
BACKGROUND: Microbial intestinal colonization in early in life is regarded to play a major role for the maturation of the immune system. Application of non-pathogenic probiotic bacteria during early infancy might protect from allergic disorders but underlying mechanisms have not been analysed so far. OBJECTIVE: The aim of the current study was to investigate the immune effects of oral application of probiotic bacteria on allergen-induced sensitization and development of airway inflammation and airway hyper-reactivity, cardinal features of bronchial asthma. METHODS: Newborn Balb/c mice received orally 10(9) CFU every second day either Lactobacillus rhamnosus GG or Bifidobacterium lactis (Bb-12) starting from birth for consecutive 8 weeks, during systemic sensitization (six intraperitoneal injections, days 29-40) and airway challenge (days 54-56) with ovalbumin. RESULTS: The administration of either Bb-12 or LGG suppressed all aspects of the asthmatic phenotype: airway reactivity, antigen-specific immunoglobulin E production and pulmonary eosinophilia (mean: 137 vs. 17 and 13 cellsx10(3)/mL, respectively). Antigen-specific recall proliferation by spleen cells and T-helper type 2 cytokine production (IL-4, IL-5 and IL-10) by mesenteric lymph node cells also showed significant reduction, while TGF production remained unchanged. Oral LGG administration particularly suppressed allergen-induced proliferative responses and was associated with an increase in numbers of TGF-beta-secreting CD4+/CD3+ T cells in mesenteric lymph nodes (6.5, 16.7%) as well as nearly 2-fold up-regulation of Foxp3-expressing cells in peribronchial lymph nodes. CONCLUSIONS: Neonatal application of probiotic bacteria inhibits subsequent allergic sensitization and airway disease in a murine model of asthma by induction of T regulatory cells associated with increased TGF-beta production. 相似文献
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本文报道2-氧化-1,3,2-二氧磷杂环己烷类衍生物的合成,希望寻找效果较好的可逆性胆碱酯酶抑制剂。初步药理实验证明,所合成的大部分化合物具有一定的抑制乙酰胆碱酯酶的作用,且毒性较低。通过对中间体Ⅱ进行质谱分析,发现该类化合物中大部分存在M-57碎片离子峰,利用高分辨质谱和亚稳离子测定,确定了该碎片离子的生成过程。 相似文献
58.
The characteristics of a glial Na+,K+-pump dependent on extracellular K+ within epileptogenic cortex were studied electrophysiologically, biochemically and histochemically in vitro using slices from cobalt-induced epileptogenic cortex of rat. When the extracellular K+ concentration ([K+]o) was varied between 4 and 40 mM, the mean slope of membrane potential plotted against [K+]o was about 57 mV in glia from the normal cortex (tissue A) and about 44 mV in glia from the epileptogenic cortex (tissue B); whereas no significant difference in the resting membrane potential of these tissues was observed. In glia from tissue B, a marked transient hyperpolarization above control level was caused by replacement of elevated [K+]o with the normal medium. Ouabain abolished these phenomena observed in glia from tissue B, but had no effect on the membrane potential during normal [K+]o. Reduction of extracellular Na+, Ca2+ and Cl− did not significantly affect the membrane potential of glia from either tissue. In tissue A, the cells marked by intracellular injection of horseradish peroxidase after intracellular recording were protoplasmic astrocytes; in tissue B, fibrous astrocytes with abnormal processes predominated. K+-dependent stimulation of Na+,K+-ATPase activity of the astrocyte-enriched fraction and its membrane preparation from tissue B was much larger than that from tissue A. A certain amount of the reaction product of K+-pNPPase activity was seen on glial plasma membrane within tissue B but not on that from tissue A. The above findings suggest that a glial Na+,K+-pump within actively firing epileptogenic cortex may be modified to increase in its activity. 相似文献
59.
介绍东芝DFP-2000A数字减影系统维修实例,并论述该机图像存储系统采用的RAID3等级的磁盘阵列。 相似文献
60.
The ionic mechanisms of the effect of extracellularly ejected recombinant human tumor necrosis factor-alpha (rhTNF-alpha) on the membrane of identified neurons R9 and R10 of Aplysia kurodai was investigated with conventional voltage-clamp, micropressure ejection, and ion substitution techniques. Micropressure-ejected rhTNF caused a marked hyperpolarization in the unclamped neuron. Clamping the same neuron at it resting potential level (-60 mV) and reejecting rhTNF-alpha with the same dose produced a slow outward current [Io (TNF)] associated with a decrease in input membrane conductance. Io (TNF) was decreased by depolarization and increased by hyperpolarization. The extrapolated reversal potential of Io (TNF) was approximately +10 mV. Ion substitution and pharmacological experiments suggest that Io (TNF) in identified neurons R9 and R10 of A. kurodai is due to a decreased Na+ conductance but not due to an activation of the Na(+)-K+ pump. Our results demonstrate that the immunomodulator TNF can act directly on the nervous system as well as on the immune system. 相似文献