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51.
Cardiac ankyrin repeat protein (CARP), which is structurally characterized by the presence of four ankyrin repeat motifs in its central region, is believed to be localized in the nucleus and to participate in the regulation of cardiac-specific gene expression in cardiomyocytes. However, we recently found that CARP was induced in skeletal muscle by denervation, leading us to speculate that CARP may be induced under some pathological conditions. In the present study, we immunohistochemically analyzed the expression of CARP in 11 cases of spinal muscular atrophy (SMA) and 14 cases of congenital myopathy. In SMA, CARP was expressed selectively in severely atrophic myofibers, suggesting that CARP expression may reflect the status of muscle atrophy. Furthermore, in the congenital myopathies, the expression patterns of CARP were distinct among the subtypes, which included nemaline myopathy, myotubular myopathy, central core disease, and congenital fiber type disproportion. Although CARP was preferentially expressed in severely damaged myofibers in nemaline myopathy, it was not detected in central core disease. These findings suggest that immunohistochemical evaluation of CARP may be helpful in the diagnosis of SMA and the congenital myopathies. 相似文献
52.
53.
Virus-like particles (VLPs, named HmTV1-17), about 40nm in diameter were found in the violet root rot fungus Helicobasidium mompa Tanaka strain No. 17, which had been isolated from an apple tree. Purified preparations of HmTV1-17 contained two species of double-stranded RNA (dsRNA), designated 17L and 17S. cDNAs were constructed from HmTV1-17 genomic dsRNAs purified using CF-11 cellulose column chromatography. The sequences of 17L and 17S cDNA comprised 5207 and 2096bp, respectively. Although 17S has no large open reading flame (ORF) on either strand, 17L has two large overlapping ORFs. The 5 located ORF1 encodes the coat protein (CP, 788 amino acids), whereas the gene product of ORF2, which is in the –1 frame relative to ORF1, shows the typical features of a RNA dependent RNA polymerase (RDRP, 845 amino acids). Phylogenetic analysis based on RDRP showed that HmTV1-17 is closely related to Sphaeropsis sapinea SsRV1, a member of the genus Totivirus from filamentous fungus S. sapinea. 相似文献
54.
Yasuyuki Tezuka Kiyokazu Imai Mitsuyoshi Oshima Tohru Chiba 《Macromolecular chemistry and physics.》1990,191(3):681-690
A structural study on O-methyl-O-hydroxypropylcellulose (MHPC) and on O-methyl-O-hydroxyethylcellulose (MHEC) was performed by means of a 13C NMR analysis after acetylation of the unsubstituted hydroxyl groups at the anhydroglucose ring and those at the end of the substituents. The carbonyl signal of the acetyl group in acetylated MHPC and MHPC samples was found to be resolved into four peaks according to the location of the acetyl function either at the 2-, 3- and 6-position of an anhydroglucose unit or at the end of an oligo(oxyalkylene) substituent, allowing to determine the distribution of methyl and oligo(oxyalkylene) substituent groups. The methyl signal of the methoxy group in MHPC was also found to be sensitive to its position either at the anhydroglucose unit or at the end of the oligo(oxypropylene) substituent. 相似文献
55.
56.
A novel insertional mutation at exon VII of the myelin proteolipid protein gene in Pelizaeus -- Merzbacher disease 总被引:1,自引:0,他引:1
Kurosawa Kenjl; Iwakl Akiko; Miyake Sho-ta; Imaizuml Kiyoshi; Kuroki Yoshikazu; Fukumakl Yasuyuki 《Human molecular genetics》1993,2(12):2187-2189
Pelizaeus Merzbacher disease (PMD) is an X-linked neurologicaldisorder characterized by dysmyelination in the central nervoussystem (CNS). Recently mutations of the myelln proteollpid protein(PLP) gene which encodes both PLP and Its Isoform, DM-20 generatedby alternative spllcing, have been demonstrated In PMD patients.We analyzed the seven exons of the PLP gene of a Japanese boyaffected with PMD by direct sequencing and identified an Insertionevent In exon Vll of the PLP gene. This mutation was also presentIn his carrier mother, but was absent In ninety-five X chromosomesof normal Japanese. The frame-shift mutation leads to the productionof truncated PLP with altered carboxyl terminal amlno acid sequences,resulting In conslderable change of the structure of PLP andDM-20 necessary for functional purposes. This is the first reportof a mutation In exon Vll of the PLP gene associated with PMD. 相似文献
57.
We compared morphological and morphometric data on various motor neurons in the human pyramidal system using the modified Klüver-Barrera staining method with extremely minimized shrinkage ratio and an image-analyzer. We classified motor neurons in the human pyramidal system into three groups according to the measurement data. This report may be of interest to better understand the process of nerve conduction in the human pyramidal system. 相似文献
58.
T cell epitopes of type II collagen in HLA-DRB1*0101 or DRB1*0405-positive Japanese patients with rheumatoid arthritis 总被引:3,自引:0,他引:3
Ohnishi Y Tsutsumi A Sakamaki T Sumida T 《International journal of molecular medicine》2003,11(3):331-335
Rheumatoid arthritis (RA) is a T cell-mediated autoimmune disease, but target antigens (autoantigens) responsible for T cell activation remain unclear. Type II collagen (CII) is a candidate autoantigen that is largely confined to the articular cartilage. To investigate whether CII is an important antigen in patients with RA, we examined peripheral blood T cell reactivity to CII in HLA-DRB1*0101 and DRB1*0405-positive RA patients. Reactivities to candidate T cell epitopes of CII were also examined. Peripheral blood T cell reactivity to CII and CII peptides (256-271, 429-442, 593-610, 1064-1081) were detected by measurement of IL-2, IFN-gamma, and IL-4 in culture supernatant of PBMC after in vitro antigen stimulation. Cytokine concentration was measured by ELISA. In DRB1*0101-positive patients, T cell reactivity to CII as detected by measurement of IL-2 production in culture supernatant, was present in 4 out of 9 patients. IL-2 production upon stimulation with CII 256-271 peptide was found in all of these 4 patients. In DRB1*0405-positive patients, high frequency of positive T cell response to CII was detected in 9 out of 11 patients. IFN-gamma production was also detected in 4 out of 6 patients producing IL-2 by stimulation with CII. T cell response to CII 256-271 and/or CII 1064-1081 was detected in these patients. In DRB1*0101-positive RA patients, CII 256-271 peptide might function as a T cell epitope, whereas either CII 256-271 or CII 1064-1081 peptide may be a major T cell epitope in DRB1*0405-positive RA patients. In DRB1*0405-positive RA patients, CII reactive T cells might play a crucial role in the development of RA through IFN-gamma production. 相似文献
59.
Maeda T Iwasaki A Kawahito S Nakata K Nonaka K Linneweber J Schulte-Eistrup S Takano T Yoshikawa M Sato K Kuwana J Murabayashi S Nosé Y 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2000,46(4):426-430
A silicone membrane hollow fiber oxygenator applicable for use as an extracorporeal membrane oxygenator (ECMO) has been developed in our laboratory. This silicone hollow fiber displays astonishing mechanical stability, is barely compressible or stretchable, and assembles easily while maintaining good gas permeability. The priming volume is 140 cc with a surface area of 0.8 m2. This study evaluated the gas transfer performances and biocompatibility of the oxygenator under ECMO and CPB conditions. In vitro studies that were performed at a blood flow rate of 2 L/min, and revealed O2 and CO2 gas transfer rates of 82.35 +/- 0.56 ml/m2/L/min and 38.72 +/- 2.88 ml/m2/L/min, respectively. The commercially available Kolobow (Avecor 1500) oxygenator was used as the control, and had O2 and CO2 gas transfer rates of 53.8 +/- 0.5 ml/m2/L/min and 24.7 +/- 2.0 ml/m2/L/min. To evaluate blood trauma, Normalized Index of Hemolysis (NIH) was measured according to American Society of Testing and Materials (ASTM) standards. The NIH findings were 0.0112 g/100L at a blood flow of 1 L/min, and 0.0152 g/100L at 5 L/min. Three ex vivo experiments, using a blood flow rate of 1 L/min, were performed with venoarterial bypass, and O2 transfer rate and CO2 transfer rate of the oxygenators were well maintained. This indicates that this preclinical silicone membrane hollow fiber oxygenator has superior efficiency, less blood trauma, and is smaller when compared with the only clinically available Kolobow oxygenator. 相似文献
60.
Taki Y Goto R Evans A Zijdenbos A Neelin P Lerch J Sato K Ono S Kinomura S Nakagawa M Sugiura M Watanabe J Kawashima R Fukuda H 《Neurobiology of aging》2004,25(4):455-463
The objectives of this study were to evaluate the correlations of the volumes of the gray matter and white matter with age, and the correlations of the tissue probabilities of the gray matter and white matter with age and several cerebrovascular risk factors. We obtained magnetic resonance (MR) images of the brain and clinical information from 769 normal Japanese subjects. We processed the MR images automatically by correcting for inter-individual differences in brain size and shape, and by segmenting the MR images into the gray matter and white matter. Volumetry of the brain revealed a significant negative correlation between the gray matter volume and age, which was not observed between white matter volume and age. Voxel-based morphometry showed that age, systolic blood pressure, and alcohol drinking correlated with the regional tissue probabilities of the gray matter and white matter. 相似文献