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排序方式: 共有366条查询结果,搜索用时 406 毫秒
1.
Jun Ogata Kentaro Hirao Kenya Nishioka Arisa Hayashida Yuanzhe Li Hiroyo Yoshino Soichiro Shimizu Nobutaka Hattori Yuzuru Imai 《International journal of molecular sciences》2021,22(7)
Leucine-rich repeat kinase 2 (LRRK2) is a major causative gene of late-onset familial Parkinson’s disease (PD). The suppression of kinase activity is believed to confer neuroprotection, as most pathogenic variants of LRRK2 associated with PD exhibit increased kinase activity. We herein report a novel LRRK2 variant—p.G2294R—located in the WD40 domain, detected through targeted gene-panel screening in a patient with familial PD. The proband showed late-onset Parkinsonism with dysautonomia and a good response to levodopa, without cognitive decline or psychosis. Cultured cell experiments revealed that p.G2294R is highly destabilized at the protein level. The LRRK2 p.G2294R protein expression was upregulated in the patient’s peripheral blood lymphocytes. However, macrophages differentiated from the same peripheral blood showed decreased LRRK2 protein levels. Moreover, our experiment indicated reduced phagocytic activity in the pathogenic yeasts and α-synuclein fibrils. This PD case presents an example wherein the decrease in LRRK2 activity did not act in a neuroprotective manner. Further investigations are needed in order to elucidate the relationship between LRRK2 expression in the central nervous system and the pathogenesis caused by altered LRRK2 activity. 相似文献
2.
Naoki Yokokawa Yutaro Masuda Eri Amasawa Hirokazu Sugiyama Masahiko Hirao 《Packaging Technology and Science》2020,33(11):445-459
This study presents systematic packaging design tools integrating functional and environmental consequences on product life cycle. To design packaging for sustainability, the trade-offs between functional and environmental aspects of packaging throughout the product life cycle should be considered. However, it is difficult for packaging designers to understand the overall trade-offs because the extent of the design consequences on the entire life cycle of packaging and its contents is unclear. We developed two tools for packaging design: the Life Cycle Association Matrix (LCAM) and the Function Network Diagram (FND). The following three steps, based on literature reviews and interviews with industrial experts, were applied. Firstly, we listed the product functions and design variables related to the functions as the attributes allocated to the product life cycle. Secondly, the attributes were connected appropriately based on causal relationships. Lastly, we identified the factors to support decision making in the packaging design procedure. As a result, the LCAM depicts the design consequences on the life cycle, and the FND determines the stakeholders affected by the design consequences. Two case studies were demonstrated to analyze the trade-offs by using our tools. In the case studies, a liquid laundry detergent bottle and a milk carton were redesigned. The tools identified the design consequences and stakeholders affected by the redesign of the usability and protective function for the detergent and milk cases, respectively. The results showed the significance of understanding the design consequences on the product life cycle by integrating the functional and environmental aspects. 相似文献
3.
High-resolution positive and negative photoresists were used to fabricate ?/4-phase-shifted corrugations by holographic exposure. To avoid mixing these photoresists, cyclised polyisoprene was used as a midlayer. The shape and depth of the corrugations on the positive and negative photoresist regions were almost the same. Single-mode operation at the Bragg wavelength was confirmed in lasers with the corrugation. 相似文献
4.
Ogi H. Nakamura N. Sato K. Hirao M. Uda S. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2003,50(5):553-560
This paper presents advanced techniques to determine all independent elastic-stiffness coefficients C/sub ij/, the associated internal friction Q/sub ij//sup -1/, and piezoelectric coefficients e/sub ij/ of monocrystal langasite (La/sub 3/Ga/sub 5/SiO/sub 14/) using a single rectangular parallelepiped specimen. Langasite's crystal structure belongs to the trigonal system with point group 32, and thus possesses six independent C/sub ij/, two e/sub ij/, and two dielectric coefficients /spl epsiv//sub ij/. All of the elastic and piezoelectric coefficients affect the mechanical resonance frequencies of the solid specimen, and measuring them very accurately permits one to determine the C/sub ij/ and e/sub ij/ with known density, dimensions, and e/sub ij/. We developed a piezoelectric tripod to support the specimen upward and measured the free-vibration resonance frequencies with minimum load from its own weight. This weak and stable acoustic coupling ensures accuracy of the frequency measurement better than 10/sup -5/, enough to determine the coefficients reliably. Our C/sub ij/ fall in the range of results measured with previous (conventional) methods. Our e/sub 11/ is smaller than the reported values by 1.2-13%, and e/sub 14/ is larger by 44-97%. For the internal friction measurement, we used a solenoid coil to vibrate the specimen without any contact. The longitudinal-wave internal friction considerably exceeds the shear-wave internal friction, which can be explained by phonon-phonon interactions. 相似文献
5.
6.
N Ide K Hirao Y Hata M Takeuchi M Irie I Yao M Deguchi A Toyoda H Nishioka A Mizoguchi Y Takai 《Canadian Metallurgical Quarterly》1998,243(2):634-638
In Caenorhabditis elegans, the vulval induction is mediated by tyrosine kinase receptor/Ras signal transduction pathway composed of the lin-3, let-23, and let-60 products. In addition to these gene products, the lin-2, lin-7, and lin-10 products are also implicated in this pathway. Lin-2 encodes a MAGUK and lin-7 encodes a small protein with one PDZ domain. The lin-10 product has no homology to known proteins. Here, we have cloned a rat homologue of the lin-10 product and characterized it. Rat lin-10 is ubiquitously expressed in various rat tissues and distributed in both the cytosol and membrane fractions. In brain, however, rat lin-10 is distributed only in the membrane fraction and enriched in the synaptic plasma membrane and postsynaptic density fractions. These results suggest that rat lin-10 is involved at least in synaptic functions in brain. 相似文献
7.
Y Hirao S Ozono Y Kagebayashi M Yoshi Y Tani H Uemura H Momose E Okajima 《Canadian Metallurgical Quarterly》1996,42(10):795-804
The number of cases of prostate carcinoma (PCA) is steadily inceasing in Japan. The clinical application of a reliable tumor marker, prostate specific antigen (PSA) for the diagnosis, as well as the increasing elderly population in Japan may account for this increase. The subjects were patients at the Nara Medical University and its affiliated hospitals; 1) 687 cases without PCA were evaluated for age-specific PSA and the incidence of abnormal PSA following urological manipulations, 2) 135 cases with histological proven BPH by transurethral resection of prostate (TUR-P) were examined for PSA density (PSAD) and positive PSA rate in BPH, 3) 135 cases receiving a needle biopsy with suspicion of PCA were examined for the efficacy of PSA and PSAD and other parameters, and 4) 459 PCA cases treated between 1988 and 1994, were examined for specific PSA and PSAD values by stage and degree of cell differentiation. The PSA assay used in this study was MARKIT-M PA (normal range < or = 3.6 ng/ml). The PSA was decreased gradually with age in non-PCA patients, and abnormal PSA was found in 5.5% of these patients following manipulations. The average PSA was 2.95 +/- 2.03 ng/ml in 130 BPH patients (mean age: 71.1 +/- 7.0 years old. and average prostate volume: 32.9 +/- 16.1 ml). And abnormal PSA level (more than 3.61 ng/ml) was found in 22.3%. The mean PSAD was 0.1.0 +/- 0.06, and PSAD was below 0.15 in 86.1% of these BPH cases. Among the 135 cases receiving a needle biopsy, 33 cases had PSA values between 3.61 and 10.0 ng/ml. Of these cases, PCA was found in 18.5% of the 27 cases with a PSAD below 1.5, and in 33.3% of the 6 cases with a PSAD over 1.5. PSA and PSAD were proportionally increased with stage, and a significant difference in the PSA value was observed between stage B1 and B2, and stage C and D (P < 0.05). However, PSA and PSAD values were not significantly correlated with the cell differentiation in PCA stage A2-C. In total, PSA was 18.1 ng/ml in well, 23.9 ng/ml in moderately and 35.9 ng/ml in poorly differentiated type PCA. The positive rate of PSA was 22.3, 65.4 and 83.5%, that of prostate acid phosphatase (PAP) was 10.0, 17.8 and 45.8%, and that of GSM was 25.0, 14.7 and 68.4%, in BPH, stage A PCA and stage BPCA, respectively. In conclusion, PSA is the most reliable tool in the diagnosis of localized PCA. However, the differential diagnosis of BPH and localized PCA is difficult when the PSA value is between 3.61 and 10.0 ng/ml, and accurate staging of localized PCA is difficult with PSA or PSAD alone. At present, it is necessary to use all possible tools for the early detection of localized PCA, and to perform the needle biopsy in all PCA-suspicious cases. 相似文献
8.
9.
Yoshitoshi Nakamura Tatsuro Sawada Akihiro Komatsu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2002,77(10):1101-1106
In order to develop a method for converting raw starch into ethanol efficiently, direct fermentation of ozonized raw starch using a recombinant yeast was investigated. Ozonolysis was carried out as a pretreatment to convert raw starch into ethanol rapidly and efficiently, and then the effect of the ozone degradation conditions on the degree of polymerization and the amount of amylose in a raw starch was determined. Since the degree of polymerization was low and the amount of amylose was high, raw starch treated with an ozone concentration of 40 gm?3 and an ozonation time of 30 min was the material chosen for alcohol fermentation. Though the recombinant yeast could not convert the untreated raw starch, it converted the soluble starch and the ozonized raw starch at a comparatively high yield into ethanol. About 56% of the ozonized raw starch decomposed, and the ethanol concentration obtained from the ozonized raw starch was markedly greater than that obtained from untreated raw starch. The dynamic behavior of cell growth, substrate degradation, and ethanol production was examined in a continuous culture under various dilution rates, and the optimal dilution rate, ie 0.15 h?1, was determined for maximizing the ethanol productivity (amount of ethanol produced per unit time). © 2002 Society of Chemical Industry 相似文献
10.
Masaki Yasuoka Kiyoshi Hirao Manuel E. Brito Shuzo Kanzaki 《Journal of the American Ceramic Society》1995,78(7):1853-1856
Control of microstructure in the Al2 O3 /LaAl11 O18 system was performed. Elongated alumina grains were formed by doping with small addition of silica, and 20 vol% lanthana- luminate was formed in situ by the reaction of LaAlO3 - A12 O3 in an alumina matrix. Strengths of over 600 MPa and a high fracture toughness (6 MPa.m1/2 ) were achieved in the material with both elongated A12 O3 grains and LaAl11 O18 platelets. Generally antagonistic properties such as strength and fracture toughness have been made compatible in the same ceramic system. 相似文献