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41.
K Hayashi Y Ohtsuki H Sonobe J Iwata M Furihata T Hikita T Kishino T Akagi 《Acta medica Okayama》1991,45(1):49-53
We present a case of pre-elastofibroma-like lesion, a kind of elastic-producing fibrous tumor. The small colonic polyp, which was found in a 49-year-old asymptomatic man in association with a large colonic adenoma, showed submucosal nodular deposits of fine granular or fibrillar eosinophilic materials with interspersed fibroblastic cells. Elastic stain revealed these deposits to consist mainly of dark gray granular or partially fibrillar dense elastinophilic materials, most of which were digested with elastase. This stromal lesion somewhat resembled a pre-elastofibroma. Therefore, pre-elastofibroma-like lesions should be kept in mind as a possible origin of colonic polyp. 相似文献
42.
Kazuko Sukegawa Shunji Tomatsu Toshiyuki Fukao Hideki Iwata Xiang-Qian Song Yukiji Yamada Seiji Fukuda Kouji Isogai Tadao Orii 《Human mutation》1995,6(2):136-143
Mucopolysaccharidosis type II (Hunter disease) is a lysosomal storage disorder caused by a deficiency of the enzyme iduronate-2-sulfatase. Varied clinical phenotypes of this disease have been described. To identify mutations in individual patients and to examine possible correlations between mutations and clinical phenotypes, we analyzed the iduronate-2-sulfatase gene in Japanese patients with different clinical phenotypes. Five missense mutations, S333L (severe), R468Q (severe), R468L (severe), W337R (intermediate), R48P (mild), and three nonsense mutations, W345X (severe), R443X (intermediate), Q531X (mild), were identified by the RT-PCR method. Transient expression in the enzyme-deficient fibroblasts revealed that all five missense mutant enzymes were synthesized as the normal-size precursor (73 kD), and the nonsense mutant enzymes were synthesized as truncated ones (W345X:54 kD, R443X:59 kD, and Q531X:69 kD), although stable mature enzymes (45–56 kD) were not detected by Western blot analysis. Further more, expression of the eight mutant cDNAs resulted in severe reductions of iduronate-2-sulfatase enzyme activity in comparison with a normal cDNA. © 1995 Wiley-Liss, Inc. 相似文献
43.
44.
Abeta-degrading endopeptidase,neprilysin, in mouse brain: synaptic and axonal localization inversely correlating with Abeta pathology 总被引:5,自引:0,他引:5
Fukami S Watanabe K Iwata N Haraoka J Lu B Gerard NP Gerard C Fraser P Westaway D St George-Hyslop P Saido TC 《Neuroscience research》2002,43(1):39-56
Metabolism of amyloid-beta peptide (Abeta) is closely associated with the pathology and etiology of Alzheimer's disease (AD). Since neprilysin is the only rate-limiting catabolic peptidase proven by reverse genetics to participate in Abeta metabolism in vivo, we performed detailed immunohistochemical analysis of neprilysin in mouse brain using neprilysin-deficient mice as a negative control. The aim was to assess, at both the cellular and subcellular levels, where Abeta undergoes neprilysin-dependent degradation in the brain and how neprilysin localization relates to Abeta pathology in amyloid precursor protein (APP)-transgenic mice. In hippocampus, neprilysin was present in the stratum pyramidale and stratum lacunosum-moleculare of the CA1-3 fields and the molecular layer of the dentate gyrus. Confocal double immunofluorescence analyses revealed the subcellular localization of neprilysin along axons and at synapses. This observation suggests that after synthesis in the soma, neprilysin, a type II membrane-associated protein, is axonally transported to the terminals, where Abeta degradation is likely to take place. Among various cell types, GABAergic and metabotropic glutamate 2/3 receptor-positive neurons but not catecholaminergic or cholinergic neurons, expressed neprilysin in hippocampus and neocortex, implying the presence of a cell type-specific mechanism that regulates neprilysin gene expression. As expected, Abeta deposition correlated inversely with neprilysin expression in TgCRND8 APP-transgenic mice. These observations not only support the notion that neprilysin functions as a major Abeta-degrading enzyme in the brain but also suggest that down-regulation of neprilysin activity, which may be caused by aging, is likely to elevate local concentrations of Abeta at and around neuronal synapses. 相似文献
45.
Seiko Iwata Yukiko Shibata Jun-ichi Kawada Shinya Hara Yukihiro Nishiyama Tsuneo Morishima Masaru Ihira Tetsushi Yoshikawa Yoshizo Asano Hiroshi Kimura 《Journal of clinical virology》2006,37(2):128-133
BACKGROUND: The loop-mediated isothermal amplification (LAMP) method is a novel technique for the amplification of specific DNA sequences. OBJECTIVES: To establish the LAMP method for amplifying Epstein-Barr virus (EBV) DNA and to examine its reliability for the detection of EBV DNA in clinical specimens. STUDY DESIGN: Sera from 108 patients, who were initially suspected of primary EBV infection, were tested by the EBV LAMP method, and the results were compared with those of the real-time PCR assay. Serological examination was regarded as the standard diagnostic method. RESULTS: To diagnose primary EBV infection, the sensitivity of LAMP was 86.4% and the specificity was 100%. The sensitivity of the real-time PCR assay was 84.1% and the specificity was 98.4%. Longitudinal analysis showed that the detection rate of EBV DNA in serum by the LAMP method decreased with time in accordance with the decrease of the EBV load. EBV DNA could not be detected in serum 40 days after onset of symptoms. CONCLUSIONS: These results indicate that the sensitivity and specificity of the LAMP method are comparable to those of real-time PCR and that detecting EBV DNA in serum by this method is potentially useful for diagnosing primary EBV infection. 相似文献
46.
Mutsuo Furihata Tamotsu Takeuchi Jun Iwata Hiroshi Sonobe Yuji Ohtsuki Akihiko Wakatsuki Nobuyuki Morioka Yusuke Sagara 《Pathology international》1998,48(12):967-973
Primary ovarian angiosarcoma is extremely rare. Only 16 cases have histologicaliy been reported to date In the Ilterature. A case of angiosarcoma arising In the right ovary of a 46-year-old female is presented. Grossly, the resected right ovary was completely replaced by a solid tumor mass, which revealed multiple necrotic and/or hemorrhagic foci. This case revealed the typical histological features of angiosarcoma with sinusoldal and solid patterns of anaplastic tumor cells. Immunohlstochemically, tumor cells were strongly and diffusely positive for CD31 and CD34, in particular, along the cytoplasmic membrane of the tumor cells. Ultrastructurally, tumor cells possessed the intermediate junctions between tumor cells, discontinuous basal laminae attached to the irregularly shaped blood vessels and occasional cytoplasmic pinocytotlc vesicles. These findings confirmed the case as being one of angiosarcoma of the ovary. The patient died 9 months after surgery as a result of developed multlfocal brain metastases. A total of 17 cases reported as primary ovarian anglosarcoma, including this presented case, are clinicopathologically reviewed. 相似文献
47.
Masashi Ikeda Nakao Iwata Tatsuyo Suzuki Tsuyoshi Kitajima Yoshio Yamanouchi Yoko Kinoshita Norio Ozaki 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2005,(1):90-92
Several lines of evidence indicate that glycogen synthase kinase-3beta (GSK3beta) is one of the candidates for schizophrenia-susceptibility factor. However, it has not been reported the association analysis between GSK3beta gene (GSK3B) and Japanese schizophrenia based on linkage disequilibrium (LD). We provide an association analysis using relatively large samples (381 schizophrenia, and 352 controls) after determination of "tag single nucleotide polymorphisms (SNPs)." In this LD mapping, we selected and genotyped for eight polymorphisms (seven SNPs and one diallelic (CAA)(n) repeat), which covered the entire region of GSK3B, and determined two "tag SNPs." In the following association analysis using these two "tag SNPs," we could not find association with Japanese schizophrenia. Furthermore, we also include subgroup analysis considering age-at-onset and subtypes, neither could we find associations. Because our samples provided quite high power, these results indicate that GSK3B may not play a major role in Japanese schizophrenia. 相似文献
48.
Murakami Y Iwata H Kitano E Kitamura H Ikada Y 《Journal of biomaterials science. Polymer edition》2005,16(3):381-395
Bioartificial pancreas, in which the islets of Langerhans are enclosed in artificial membrane to be protected from the host immune system, is expected to be a promising medical device to treat patients who suffer from insulin-dependent diabetes. Our strategy for preparation of a bioartificial pancreas involves utilizing a membrane including polymeric materials that can inhibit the complement reaction. In this study, we examined the effects of poly(styrene sulfonic acid) (PSSa) on the alternative pathway of the serum complement system to identify the mechanism(s) involved. PSSa was dissolved in pooled normal human serum (NHS), and the mixtures were incubated at 37 degrees C for 30 min. Complement activities in sera were determined by hemolytic assays. Amounts of complement activation products released were determined by ELISA. Interactions of PSSa with complement components and fragments were examined with electrophoresis and immunoblotting. From these examinations, it appeared that the manner of PSSa effects on the alternative pathway (AP) highly depends on its concentration. PSSa seemingly acted as an activator when its concentration was 0.005 g/dl to 0.05 g/dl, while it acted as an inhibitor when its concentration was more than 0.1 g/dl. In terms of activation or inhibition of the AP, forming complex of PSSa with factor H induced activation, and that with factor D induced inhibition. 相似文献
49.
Hirata I Hioki Y Toda M Kitazawa T Murakami Y Kitano E Kitamura H Ikada Y Iwata H 《Journal of biomedical materials research. Part A》2003,66(3):669-676
Since complement activation is recognized as a common response of the host defense system when an artificial medical device is applied to a patient, great effort has been devoted to studies on the interaction of the complement system with artificial materials. However, some uncertainties remain, partially because of the lack of well characterized surfaces and suitable analytic methods for study of the surface phenomena that occur on artificial materials under physiologic conditions. In this study, we employed self-assembled monolayers (SAMs) and the surface plasmon resonance (SPR) technique to study interactions of the serum complement with well characterized surfaces. Self-assembled monolayers carrying various concentrations of hydroxyl groups were prepared using 11-mercapto-1-undecanol (C11-OH) and one of n-nonanethiol, n-dodecanethiol, and n-hexadecanethiol. The amount of NHS deposition on the SAMs increased with increasing C11-OH content of the SAMs, and the amount of anti-C3b antibody immobilization formed on the NHS deposition layers increased with increasing C11-OH content of the SAMs. These results clearly demonstrate that a large amount of C3b, produced through the activation of the complement system, binds covalently to and is adsorbed by hydroxyl-group-rich surfaces. The combination of SAMs and the SPR technique is suitable for studying the interaction of the complement system with solid surfaces, and the results should give basic information needed for a rational design of biocompatible surfaces on synthetic materials. 相似文献
50.
Tadaaki Yokota Yoshimi Yamashita Yoshiko Okuzono Mutsuo Takahashi Shigeyoshi Fujihara Shin'ichiro Akizuki Tokuhiro Ishihara Fumiya Uchino Takako Iwata 《Pathology international》1984,34(3):663-668
A case of malignant cystosarcoma phyllodes of the prostate is reported in a 45-year-old male. This tumor was composed of benign columnar or squamous cystic folds and sarcomatous stroma including rhabdomyomatous elements. The prostatic origin of the tumor was clearly proved by the unlabeled immunoperoxidase method. ACTA PATHOL. JPN. 34: 663–668, 1984. 相似文献