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1.
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.
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   
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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   
5.
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   
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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   
8.
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   
9.
We examined the influence of polyaniline (PAn)'s unit sequence and doping with low molecular weight dopants or polymer dopants on permeation property. It was found that CO2 permeability was increased by the formation of a quinonediimine unit in PAn with the oxidation. CO2 sorption amount of PAn was decreased by oxidation. The increase of CO2 permeability with oxidation, therefore, resulted from the increase of diffusivity, which was attributable to morphological variation by the increase of a quinonediimine unit. The permselectivity of PAn films was found to be remarkably improved by doping. In particular, the selectivity value of the PAn film doped with polyvinyl sulphonic acid as a polymer dopant went up to over 2,000. This remarkable increase of selectivity was found to result in the increase of selectivity, depending on diffusivity. It was also found that the permselectivity of the PAn film doped by polymer dopants was surpassed, as compared with that doped by low molecular dopants. © 1995 John Wiley & Sons, Inc.  相似文献   
10.
The crystalline structures of inclusion complexes of γ-cyclodextrin (γ-CD) with poly(ethylene glycol), poly(ethylene adipate), poly(propylene glycol) and poly(isobutylene) were studied by electron microscopy, in combination with X-ray diffraction works and measurements of thermal properties by DSC and TGA. The crystalline structure of as-prepared complexes was tetragonal and its cell dimensions were a = b = 2.380 nm and c = 1.48 nm. When an as-prepared sample was dried in a vacuum at room temperature, the tetragonal modification was transformed into the monoclinic one with the projected cell dimensions of a = 1.75, b = 1.36 nm and γ = 110°. The transformation occurred by progressive ‘shifting’ of rows of polymer necklaces in the [110] direction along the (110) plane in an original tetragonal lamellar crystal. Complexes lost weight by 10-15% in the process of heating up to 140 °C. The tetragonal crystalline modification was transformed into the hexagonal one, and concurrently, the X-ray diffraction profiles of annealed complexes were broadened. When a sample was dried in a vacuum at room temperature or annealed at high temperatures, followed by exposure to water vapor, the original tetragonal crystalline structure was recovered, restoring the original degree of orientation of crystallites in the sample. When water molecules were removed, the lateral stacking order of γ-CD-polymer complexes was destroyed, but the basic necklace structure in which polymer chains threaded through the cavity of γ-CD rings' structure could be retained.  相似文献   
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