518 research outputs found

    Protein-crystal growth experiment (planned)

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    To evaluate the effectiveness of a microgravity environment on protein crystal growth, a system was developed using 5 cubic feet Get Away Special payload canister. In the experiment, protein (myoglobin) will be simultaneously crystallized from an aqueous solution in 16 crystallization units using three types of crystallization methods, i.e., batch, vapor diffusion, and free interface diffusion. Each unit has two compartments: one for the protein solution and the other for the ammonium sulfate solution. Compartments are separated by thick acrylic or thin stainless steel plates. Crystallization will be started by sliding out the plates, then will be periodically recorded up to 120 hours by a still camera. The temperature will be passively controlled by a phase transition thermal storage component and recorded in IC memory throughout the experiment. Microgravity environment can then be evaluated for protein crystal growth by comparing crystallization in space with that on Earth

    Rudolf Steiner’s Theory of Foreign Language Learning

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    Rudolf Steiner is best known as the founder of the philosophical movement Anthroposophie and as the ideological father of Waldorf schools. The Waldorf school program follows Steiner\u27s education principles in that it teaches children to explore their world with all senses. The goal of Waldorf education is to help children develop their soul and spirit in order to become a conscious, mature adult. Waldorf schools introduce two foreign languages at grade one in order to raise world-awareness in children and young adults. This study reviews Steiner\u27s biographic background until the opening of the first Waldorf school. It highlights Steiner\u27s spiritual development, projects it against the background of philosophical movements at the turn of the twentieth century, and portrays Anthroposophie as a new cultural direction. It then details Steiner\u27s theory of education and its consequences for foreign language teaching at Waldorf schools and will give meaning to Steiner\u27s ambiguous spiritual language. Respect for humankind in general and teaching students to become balanced, spiritual individuals by nurturing them according to their strengths and weaknesses accent Steiner\u27s educational principles. Finally, this work critically examines Steiner\u27s specific theory about foreign language learning with respect to his theory of speech and language development. It presents Steiner\u27s original ideas, compares them to subsequent developments in teaching at Waldorf schools in regard to goals, content, methods, and contrasts it with the language program at the German American School

    Reconstruction of GABAergic Transmission and Behavior by Striatal Cell Grafts in Rats with Ischemic Infarcts in the Middle Cerebral Artery

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    Fetal striatal cell suspensions were grafted stereotaxically into the infarcted striatum of rats, and reconstruction of striatopallidal GABA transmission and behavior were investigated. Occlusion of the middle cerebral artery (MCA) for one hour induced ischemic infarcts mainly in the lateral striatum, as detected by magnetic resonance imaging (MRI) and histology. Ischemic rats had deficits in the performance of a passive avoidance task, both acquisition and retention, but no changes in general circadian actograms. In these animals pallidal GABA, detected by microdialysis, decreased to about half of control levels. There were suggestions of an improvement in passive avoidance performance in the grafted animals. Pallidal GABA concentrations recovered almost to control levels, and were increased by infusions of the GABA uptake blocker nipecotic acid. These data indicate that neural transplantation is a promising approach to improve the deficits in chemical transmission and behavior following ischemic infarcts in rat striatum

    Selection of Mouse Strains Showing High and Low-incidences of Alloxan-induced Diabetes and Quantitative Morphological Analysis of Langerhan's Islands in Two Strains

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    ヒト疾患モデル動物を開発する目的で,古くから実験的糖尿病として知られているアロキサン誘発糖尿病をとりあげ,ICR系マウスを選抜基礎集団として,高発症系,低発症系への選抜育種を20代まで継続し,近交系として確立することができた.得られた結果は以下の通りである. 1.選抜20代における発症率は,高発症系で98.9%,低発症系で0%であった.選抜世代に伴う発症率の変化は,高発症系では13代で98.7%,低発症系では7代で0%に達し,それ以後の世代においては一定の範囲内で推移した.本実験で用いたED50値では,両系統とも,すでに選抜限界に達したものと考えられる.また,本実験で採用した兄妹交配法により,選抜20代における両系統の近交係数値は98.6%となり,両系統は近交系として確立された. 2.選抜20代における血糖値は,高発症系で455mg/dl,低発症系で127mg/dl,を示した.選抜世代に伴う血糖値の変化は,高発症系では8代で395mg/dlとなり,それ以後の世代では350~400mg/dl前後の値で推移した.低発症系では7代で128mg/dlとなり,それ以後の世代では120~130mg/dlの範囲内で推移した. 3.近交系として確立された高発症系,低発症系について,膵臓単位面積に占める膵島面積,膵島数,膵島全細胞に占めるβ細胞数の割合などについて定量形態学的検討を加えたが,コントロール区では,低発症系が高発症系に比較して,いずれの測定値についても有意に多く,またアロキサン投与区においても同様の傾向にあることが確認された.以上の結果から,アロキサンに対する感受性の違いで選抜世代を進めてきた高発症系,低発症系が膵臓組織の定量形態学的特性によって特徴づけられてきていることが確認された

    Effects of 17β-oestradiol on rat detrusor smooth muscle contractility

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    The aim of this study was to investigate the effect of 17β-oestradiol (E2) on detrusor smooth muscle contractility and its possible neuroprotective role against ischaemic-like condition, which could arise during overactive bladder disease. The effect of E2 was investigated on rat detrusor muscle strips stimulated with carbachol, KCl and electrically, in the absence or presence of a selective oestrogen receptor antagonist (ICI 182,780) and, by using confocal Ca2+ imaging technique, measuring the amplitude (ΔF/F0) and the frequency of spontaneous whole cell Ca2+ flashes. Moreover, the effect of 1 and 2 h of anoxia–glucopenia and reperfusion (A-G/R), in the absence or presence of the hormone, was evaluated in rat detrusor strips perfused with Krebs solution which underwent electrical field stimulation to stimulate intrinsic nerves; the amplitude and the frequency of Ca2+ flashes were also measured. 17β-Oestradiol exhibited antispasmogenic activity assessed on detrusor strips depolarized with 60 mm KCl at two different Ca2+ concentrations. 17β-Oestradiol at the highest concentration tested (30 μm) significantly decreased detrusor contractions induced by all the stimuli applied. In addition, the amplitude and the frequency of spontaneous Ca2+ flashes were significantly decreased in the presence of E2 (10 and 30 μm) compared with control detrusor strips. In strips subjected to A-G/R, a significant increase in the amplitude of both spontaneous and evoked flashes was observed. 17β-Oestradiol was found to increase the recovery of detrusor strips subjected to A-G/R. The ability of E2 to suppress contraction in control conditions may explain its ability to aid recovery following A-G/R

    New targets for overactive bladder-ICI-RS 2109

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    Aim: To review evidence for novel drug targets that can manage overactive bladder (OAB) symptoms. Methods: A think tank considered evidence from the literature and their own research experience to propose new drug targets in the urinary bladder to characterize their use to treat OAB. Results: Five classes of agents or cellular pathways were considered. (a) Cyclic nucleotide–dependent (cyclic adenosine monophosphate and cyclic guanosine monophosphate) pathways that modulate adenosine triphosphate release from motor nerves and urothelium. (b) Novel targets for β3 agonists, including the bladder wall vasculature and muscularis mucosa. (c) Several TRP channels (TRPV1, TRPV4, TRPA1, and TRPM4) and their modulators in affecting detrusor overactivity. (d) Small conductance Ca2+-activated K+ channels and their influence on spontaneous contractions. (e) Antifibrosis agents that act to modulate directly or indirectly the TGF-β pathway—the canonical fibrosis pathway. Conclusions: The specificity of action remains a consideration if particular classes of agents can be considered for future development as receptors or pathways that mediate actions of the above mentioned potential agents are distributed among most organ systems. The tasks are to determine more detail of the pathological changes that occur in the OAB and how the specificity of potential drugs may be directed to bladder pathological changes. An important conclusion was that the storage, not the voiding, phase in the micturition cycle should be investigated and potential targets lie in the whole range of tissue in the bladder wall and not just detrusor
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