Mass spectrometry of hydrogen/deuterium exchange in 70S ribosomal proteins from E. coli

AbstractThe 70S ribosome from Escherichia coli is a supermacro complex (MW: 2.7MDa) comprising three RNA molecules and more than 50 proteins. We have for the first time successfully analyzed the flexibility of 70S ribosomal proteins in solution by detecting the hydrogen/deuterium exchange with mass spectrometry. Based on the deuterium incorporation map of the X-ray structure obtained at the time of each exchange, we demonstrate the structure–flexibility–function relationship of ribosome focusing on the deuterium incorporation of the proteins binding ligands (tRNA, mRNA, and elongation factor) and the relation with structural assembly processes

Experimental Investigation on Crushing of Granular Material in One-Dimensional Test

A series of one-dimensional compression tests have been carried out on three kinds of granular materials in a dense state to investigate their mechanical and crushing behaviours. A new testing apparatus that can simultaneously measure the axial and lateral stresses acted on the cylindrical specimen was also developed.Experimental results show that the break-point stress on e – log p curve is the largest for glass beads ballotini. A rise in compression index with the increasing axial load is observed for all three granular materials. The lateral earth pressure coefficient at rest Ko for the three granular materials slightly increases with the increasing axial load and attains a steady value between 0.25 and 0.3 at the initial loading stage. The value for Ko markedly increases as the axial load is removed during the unloading process. The axial strain of Masado is the largest at the same axial load level due to its mineral hardness. Experimental results demonstrate that the crushing degree of granular material is greatly influenced by the loading modes and conditions

第17章 InterregIII/A・ギリシャ＝トルコの役割

平成14年度～平成17年度科学研究費補助金(基盤研究 (A))　「国境を越える地域経済ガバナンス・EU諸地域の先行例を中心とした比較研究」 (課題番号 14252007) 研究成果報告書

Claw sign predicts first-pass effect in MT

Background: Mechanical thrombectomy (MT) is an effective treatment for acute cerebral large vessel occlusion (LVO). Complete recanalization of vessels in a single procedure is defined as the first-pass effect (FPE) and is associated with good prognosis. In this study, angiographic clot protruding sign termed the “claw sign,” was examined as candidate preoperative imaging factor for predicting the FPE. Methods: We retrospectively analyzed data from 91 consecutive patients treated for acute LVO in the anterior circulation by MT between January 2014 and December 2019. The claw sign was defined as a thrombus that protruded proximally by more than half of the diameter of the parent artery. Radiological findings such as claw sign, clinical and etiological features, and outcomes were compared between groups with and without successful FPE. Multivariate analysis was conducted to evaluate perioperative factors associated with FPE. Results: FPE was achieved in 26 of 91 (28.6%) patients and the claw sign was observed in 34 of 91 (37.4%) patients. The claw sign was significantly more frequent in the successful FPE group than in the failed FPE group (53.8% vs. 30.8%; P = 0.040). After the multivariate analysis, the claw sign was the only pretreatment parameter that could predict FPE (odds ratio, 2.67; 95% confidence interval, 1.01–7.06; P = 0.047). Conclusion: The claw sign is an angiographic imaging factor that might predict FPE after MT for anterior circulation acute ischemic stroke

AN ANGIOGRAPHICAL PREDICTOR FOR SUCCESSFUL RECANALIZATION

Background: Mechanical thrombectomy undoubtedly improves functional outcomes for patients with acute ischemic stroke. Although we have observed occlusion sites that protrude proximally into the vessel on angiography, termed the “claw sign,” we have been unable to state its clinical significance. In this study, we aimed to determine whether the presence of a claw sign was related to recanalization success after mechanical thrombectomy. Materials and Methods: We retrospectively included 73 consecutive patients treated for acute cerebral large vessel occlusion by mechanical thrombectomy between January 2014 and December 2017. The angiographic claw sign was defined as a thrombus that protruded proximally by more than half the diameter of the parent artery. Claw sign positivity, clinical and etiological features, and outcomes were compared between groups with and without recanalization. Results: The claw sign was observed in 29 of 73 (40%) patients and was positive significantly more frequently in those with recanalization (50.0%) than in those without recanalization (5.9%) (P < .01). By multivariate analysis, the claw sign was the only pretreatment parameter to predict successful recanalization (odds ratio, 12.50; 95% confidence interval, 1.50-103.00; P = .019). Conclusions: The presence of the claw sign might predict successful recanalization in patients undergoing mechanical thrombectomy for large vessel occlusion

脳卒中と認知症の予防

It became an important issue how we can live long in good health. Because stroke and dementia bring physical disability and cognitive functional decline and often need care, the treatment and prevention of those diseases are important. The number of stroke patients is increasing, but treatments for acute stroke has remarkably progressed, especially those by the endovascular therapy. Managing hypertension, diabetes mellitus, dyslipidemia and atrial fibrillation is key of the prevention. Because dementia patients are increasing remarkably, the countermeasures become the important problem of the country. Of the causes of dementia, Alzheimer disease is the most frequent followed by vascular dementia. Vascular dementia occurs due to cerebrovascular diseases. Therefore, it is important to manage hypertension, diabetes mellitus, dyslipidemia and atrial fibrillation for preventing vascular dementia. The etiology of Alzheimer disease is still unknown. A recent study suggests the possibility that hypertension, diabetes mellitus and dyslipidemia are involved in an etiology of Alzheimer disease. It may be effective for the prevention of Alzheimer disease to manage hypertension, diabetes mellitus and dyslipidemia

Development and validation of the short version of metacognitions questionnaire-Insomnia

Waine, Broomfield, Banham, & Espie (2009) developed and validated the Metacognitions Questionnaire-Insomnia (MCQ-I) to assess metacognition about sleep, which was hypothesized to have a two-factor structure consisting of metacognitive belief about sleep, and metacognitive plans about sleep. However, it is unclear if the MCQ-I reflects metacognition about sleep as hypothesized because no item analysis or factor analysis was conducted. The present study was designed to develop a short version of MCQ-I using selected items and investigate its reliability and validity. A cross-sectional survey using the MCQ-I was conducted with undergraduates (N=330) and 27 patients with chronic insomnia disorder. Results of factor analysis and item analysis of their responses indicated that MCQ-I has a two-factor structure as hypothesized, and 25 items had high internal consistency. Moreover, the MCQ-I-25 was correlated with metacognition about worry, comprehensive dimensions of cognitive arousal, and sleep disturbances. Furthermore, the MCQ-I-25 score was higher in insomnia patients than healthy students. These results suggest that MCQ-I-25 reflects metacognition about sleep and could predict cognitive arousal and insomnia