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31.
Electron-dense deposition patterns and the outcomes of idiopathic membranous nephropathy in Japanese 总被引:1,自引:0,他引:1
Hitoshi Yokoyama Keiichi Yoshimoto Takashi Wada Kengo Furuichi Satoshi Goshima Hiroshi Kida Ken-ichi Kobayashi 《Medical Electron Microscopy》2002,35(2):81-86
A considerable diversity in prognosis is seen with membranous nephropathy (MN). In terms of pathological findings, the presence of tubulointerstitial lesions was emphasized as a poor prognostic factor. However, the glomerular factors affecting the long-term outcome of idiopathic human MN have remained unclear. We reviewed the initial clinicopathological factors affecting the primary and secondary outcomes in 105 patients with primary MN, as well as reviewing previous reports. Based on electron microscopic (EM) findings, we could divide patients into two subtypes and one subgroup; i.e., homogeneous type with a synchronous phase of electron-dense deposits, with large dense deposits (deep subgroup) and heterogeneous type with various phases of dense deposits. The homogeneous type showed no endstage renal failure, and had earlier remission as compared with the heterogeneous type. For the secondary outcome, heterogeneous type and deep subgroup were also independent risk factors. However, there was no significant difference in the final primary or secondary outcome for any treatment subgroups. These results indicated that our category of EM findings was a beneficial marker of the primary and secondary outcomes in MN; the homogeneous type of MN with synchronous phase of electron-dense deposits (except for the "deep" subgroup) had a good outcome. 相似文献
32.
Ken-ichi Sasaki Yasuo Kokai Shin-ichi Atsumi Hirotoshi Tobioka Norimasa Sawada Koichi Hirata Michio Mori 《Medical Electron Microscopy》1998,31(2):61-67
Epithelioid disorganization is a hallmark of gastrointestinal cancers and is believed to be associated with malignant phenotypes such as invasiveness and the potentiality for metastasis. Although tight junctions (TJs) are known to be crucial for the maintenance of polarized organization of the gastrointestinal epithelium, changes in the TJ proteins in human cancers have not yet been fully elucidated. In this report, we investigated the expression and localization of three TJ proteins-barmotin (7H6 antigen), occludin, and ZO-1-in three phenotypically different human colon cancer cell lines exhibiting differnt grades of epithelioid organization. All three proteins were localized at the most apical part of the cell border corresponding to the site of TJs in T84 cells, in which epithelioid organization was well preserved. In contrast, in COLO320DM cells, which showed no epithelioid phenotypes, occludin was not detectable at either the protein or mRNA level, although barmotin and ZO-1 were present in the cytoplasm. In the third cell line, DLD-1, which showed an epithelioid phenotype intermediate between T84 and COLO320DM, aberrant expression of occludin was found in the basolateral cell membrane. On the other hand, barmotin was present in the cytoplasm, whereas ZO-1 was localized at the cell border. These observations showed that changes in the expression of TJ proteins occur in close correlation with epithelioid disorganization in human colon cancers. 相似文献
33.
Lysosome is a primary organelle in B cell receptor-mediated apoptosis: an indispensable role of Syk in lysosomal function 总被引:3,自引:0,他引:3
He J Tohyama Y Yamamoto K Kobayashi M Shi Y Takano T Noda C Tohyama K Yamamura H 《Genes to cells : devoted to molecular & cellular mechanisms》2005,10(1):23-35
To investigate the mechanism of B cell receptor (BCR)-mediated apoptosis, we utilized immature B cell lines, DT40 and WEHI-231. In both cell lines, BCR-crosslinking caused the increase in lysosomal pH with early apoptotic changes characterized by chromatin condensation and phosphatidylserine exposure. This increase was detected in c-Abl-deficient DT40 cells but not in Syk-deficient cells, which corresponded to the fact that the former cells but not the latter revealed BCR-induced apoptosis. In contrast, BCR-crosslinking caused no apparent change in mitochondrial transmembrane potential. Therefore, the lysosomal change might be a primary event in BCR-induced apoptosis in DT40 cells. The increased activity of cathepsin B and apoptosis-preventing effect of a cathepsin inhibitor suggested a significant role of lysosomal enzymes in this apoptosis. By microscopic studies, lysosomes of wild-type DT40 cells fused to BCR-carrying endosomes became enlarged and accumulated one another. In contrast, these changes of lysosomal dynamics did not occur in Syk-deficient cells but transfer of wild-type Syk restored the lysosomal changes and apoptosis. These results demonstrated that the lysosomal change accompanied with the activation of lysosomal enzymes is a primary step in BCR-crosslinking-mediated apoptosis and Syk is responsible for this step through the fusion of BCR-carrying endosomes to lysosomes. 相似文献
34.
Hideo Kunisada Yasuo Yuki Shuji Kondo Ken-ichi Goto 《Macromolecular chemistry and physics.》1993,194(5):1323-1334
Monomers containing several octadecyl groups, e.g., 2-isopropenyl-4,6-bis(octadecylamino)-1,3,5-triazine ( 2 ), 2-dioctadecylamino-4-isopropenyl-6-octadecylamino-1,3,5-triazine ( 3 ) and 2,4-bis(dioctadecylamino)-6-isopropenly-1,3,5-triazine ( 4 ) were prepared by the alkylation reaction of 2,4-diamino-6-isopropenyl-1,3,5-triazine ( 1 ) with 1-bromooctadecane in the presence of sodium hydride. In the free-radical homopolymerization of these monomers, the polymer yield of 3 was lower than that of 2 due to a decrease in the ceiling temperature, and the polymerization of 4 did not proceed. Copolymerizations of these monomers with styrene or methyl methacrylate were carried out and the monomer reactivity ratios (r1 and r2) were determined. The monomer reactivity decreased with increasing the number of octadecyl groups in the monomers. Crystallinity of the octadecyl side chains in the resulting comb-like polymers was evaluated by differential scanning calorimetry. 相似文献
35.
Tsukamoto Y Yamamoto T Okado H Nibu K Terashima T 《Archives of histology and cytology》2003,66(3):209-220
The present study tested whether a gene-transfer based upon the retrograde axonal transport of the lacZ adenovirus is effective in the spinal descending tracts of the adult mouse. A small volume of a replication-defective recombinant adenovirus encoding E. coli beta-galactosidase was injected into the upper lumbar cord, and, seven days later, the mice were transcardially perfused by a fixative solution. X-gal staining of coronal or sagittal sections of the spinal cord and the brain revealed that many sites of origin for rubrospinal, vestibulospinal, and reticulospinal tracts were retrogradely labeled, whereas few of the corticospinal tract neurons were retrogradely labeled. Ependymal cells surrounding the central canal of the spinal cord, which were located far from the injection site, showed a high expression of beta-galactosidase activity. Motoneurons around the injection site were strongly stained by X-gal staining, and their axons in the ventral root were anterogradely labeled. Afferent fibers in the dorsal root were labeled by the transganglionic transport of beta-galactosidase. To examine the efficacy of the uptake and retrograde transport of HRP and adenovirus, we injected a mixed solution of 10% HRP and recombinant adenovirus. The number of HRP-labeled corticospinal neurons overwhelmed the number of X-gal stained ones, while the numbers of HRP-labeled rubrospinal and subcoeruleus-spinal neurons were smaller in comparison with the numbers of beta-galactosidase-positive counterparts. The present study revealed that the origins for the spinal descending tracts except for corticospinal neurons could be efficiently gene-transferred by the retrograde infection of a recombinant adenovirus. Such a difference in efficacy of retrograde infection among the spinal descending tracts is practically important when an adenovirus-mediated gene transfer is designed to treat certain neurological diseases affecting the spinal descending tracts. 相似文献
36.
Makita Ayu Nagao Tomoaki Miyoshi Ken-ichi Koizumi Yohei Kurata Mie Kondo Fumikazu Shichijo Satoru Hirooka Masashi Yamaguchi Osamu 《Clinical and experimental nephrology》2021,25(9):981-987
Clinical and Experimental Nephrology - The progression of chronic kidney disease (CKD) depends on the extent of fibrosis in the kidneys; however, a renal biopsy is necessary to evaluate the... 相似文献
37.
38.
The relationship between physical stability of freeze-dried cakes and protein stability during storage was studied using -galactosidase as a model protein and inositol as an excipient. Amorphous samples freeze-dried from solutions containing the enzyme and various concentrations of inositol in sodium phosphate buffer (50 mM, pH 7.4) were stored for 7 days over P2O5 at 40 to 70°C. Structural collapse and inositol crystallization were observed in some of the samples, depending on the formulation and storage temperature. The physical stability of freeze-dried samples was also studied by differential scanning calorimeter (DSC). Inositol showed a protein-stabilizing effect when its amorphous form was retained during storage, regardless of structural collapse. However, crystallization of inositol during storage removed its stabilizing effect. Addition of water-soluble polymers such as dextran, Ficoll and carboxymethyl cellulose sodium salt (CMC-Na) preserved activity of the enzyme by preventing inositol crystallization. 相似文献
39.
Ken-ichi Ueno Hiroko Togashi Mitsuhiro Yoshioka 《Nihon shinkei seishin yakurigaku zasshi》2003,23(1):47-55
The present study was undertaken to evaluate juvenile stroke-prone spontaneously hypertensive rats (SHRSP) as an animal model of attention-deficit/hyperactivity disorder (AD/HD). Juvenile SHRSP showed significant increases in horizontal ambulatory activity and vertical rearing activity in the open field as compared with genetic control Wistar-Kyoto rats (WKY). Anxiety-related behavior assessed by elevated plus-maze as an index of impulsivity, the entries into open arms and the spent time in the open arms of SHRSP were significantly higher than those of WKY. Spontaneous alternation behavior requiring attention and working memory in the Y-maze was significantly impaired in male, but not female, SHRSP when compared with sex-matched WKY. Hippocampal long-term potentiation formation, a cellular model of learning and memory, was not impaired in SHRSP. Methylphenidate, a first choice psychostimulant for AD/HD, significantly alleviated the hyperactivity in SHRSP. However, intense impulsivity of SHRSP was not improved by methylphenidate. Methylphenidate dose-dependently and significantly ameliorated the impaired spontaneous alteration behavior in male SHRSP. These results suggest that juvenile male SHRSP manifest problematic behavior resembling ADHD, namely inattention, hyperactivity and impulsivity. Methylphenidate alleviates the behavioral symptoms of hyperactivity and inattention. Thus, juvenile male SHRSP might be a useful behavioral animal model of AD/HD, from behavioral and pharmacological perspectives. 相似文献
40.
Keiichi Ichimura Masashi Sugasawa Ken-ichi Nibu Esao Takasago Kenji Hasezawa 《Auris, nasus, larynx》1997,24(4):391-397
We sometimes experience patients with persistent or progressive arytenoid edema, among which residual or recurrent cancer is often accompanied. Because it is difficult to distinguish tumour rest or recurrence from normal tissue sequelae in the early period after irradiation, it is important to know both the contributing factors for arytenoid edema, and the incidence of residual or recurrent tumours in patients with postirradiation laryngeal edema. We therefore reviewed the charts of 67 patients with early laryngeal carcinoma who had received a curative dose of irradiation in the last 5 years. Fourteen patients (20.9%) had moderate or severe laryngeal edema persisting for or developing at more than 3 months after completion of a course of definitive radiotherapy. The incidence was highest in supraglottic T2 disease, followed by glottic T2 tumour. Of the 14 patients with edema, six (42.9%) had persistent or recurrent disease. The primary disease was uncontrolled in 18 patients, 17 of whom received successful salvage surgery. In patients without residual tumours, the edema was usually moderate and resolved within a year, although four patients had chronic edema lasting more than a year after treatment. All four had supraglottic T2 lesions and received 70 Gy of X-ray. We also reviewed, for sake of comparison, the records of 38 patients treated with radiotherapy at doses of more than 40 Gy between l975 and 1980, when endoscopic microsurgery for laryngeal cancer was introduced as a primary part of treatment. The incidence of persistent or late developed edema over the period, though not significant, was 36.8%: nearly twice that of the last 5 years. Microscopic endolaryngeal surgical procedures seem to have been a causal factor for edema in this period. 相似文献