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11.
Tetsushi Furukawa Tei-ichi Yamane Tomoko Terai Yoshifumi Katayama Masayasu Hiraoka 《Pflügers Archiv : European journal of physiology》1996,431(4):504-512
The role of the cytoskeleton in the rundown and reactivation of adenosine triphosphate (ATP) sensitive K+ channels (KATP channels) was examined by perturbing selectively the intracellular surface of inside-out membrane patches excised from guinea-pig ventricular myocytes. Actin filament-depolymerizing agents (cytochalasins and desoxyribonuclease I) accelerated channel rundown, while actin filament stabilizer (phalloidin) or phosphatidylinositol biphosphate (PIP2; inhibitor of F-actin-severing proteins) inhibited spontaneous and/or Ca2+-induced rundown. When rundown was induced by cytochalasin D or by long exposure to high Ca2+, channel activity could not be restored by exposure to MgATP, but application of F-actin with MgATP could reinstitute channel activity. The processes of rundown and reactivation of cardiac KATP channels may thus be influenced by the assembly and disassembly of the actin cytoskeletal network, which provides a novel regulatory mechanism of this channel. 相似文献
12.
Toshiaki Moriki Tamotsu Takahashi Makoto Hiroi Toshiko Yamane Hiroshi Hara 《Pathology international》1996,46(6):417-425
Thirty cases of invasive ductal carcinoma of the breast were classified to histological subtype according to the General Rules for Clinical and Pathological Recording of Breast Cancer of the Japanese Breast Cancer Society and histologically graded using the Nottingham method and the correlation of histology with proliferative activity was investigated using bromodeoxyuridine (BrdU). In addition, the overexpression of p53 protein, c-erbB-2 oncoprotein and estrogen receptor (ER) were immunohistochemically examined in order to discuss the relationship with histological subtype and histological grade. Histological grade correlated positively to the BrdU labeling index (LI) and overexpression of p53. High grade carcinoma demonstrated c-erbB-2 more frequently and exhibited a low incidence of ER. However, no significant relationship was found between BrdU LI, overexpression of p53 and c-erbB-2 and histological subtype. These results suggest that the histological grade does represent the proliferative activity of tumor cells and that adding the histological grade to the pathological diagnosis in invasive ductal breast carcinoma may be useful from the clinicopathological aspect concerning tumor behavior. 相似文献
13.
Increased expression levels of integrin alphavbeta5 on scleroderma fibroblasts 总被引:1,自引:0,他引:1 下载免费PDF全文
Integrin alphavbeta5 is a receptor for vitronectin, a plasma glycoprotein that is also distributed in extracellular matrix of various tissues. Matrix-bound vitronectin has the potential to stabilize the active form of plasminogen activator inhibitor-1, resulting in the inhibition of the plasmin-mediated pericellular proteolytic cascade. In this study, we compared the levels of alphavbeta5 and matrix-bound vitronectin between normal and scleroderma fibroblasts and investigated the association with fibrosis. We demonstrated that alphavbeta5 was up-regulated on scleroderma fibroblasts. The up-regulated alphavbeta5 contributed to the increase in vitronectin-binding ability in scleroderma fibroblasts, which led to the vitronectin-dependent activation of plasminogen activator inhibitor-1. In immunohistochemistry, the alphav and beta5 subunits were stained strongly on scleroderma fibroblasts and the amount of vitronectin was increased in the pericellular matrix of those cells. The transient overexpression of alphavbeta5 on normal fibroblasts enhanced the human alpha2(I) collagen promoter activity through Sp-1 and Smad3 as well as the vitronectin-dependent plasminogen activator inhibitor-1 activity. This effect on the promoter activity was also observed in the absence of vitronectin and completely disappeared in the presence of anti-alphavbeta5 antibody. These results indicate that the up-regulated alphavbeta5 may contribute to the phenotypical alteration of scleroderma fibroblasts, while at the same time suppressing the plasmin-mediated pericellular proteolytic cascade. 相似文献
14.
Kojima M Nakamura S Shimizu K Yamane Y Itoh H Masawa N 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(12):1133-1136
A completely infarcted lymph node is an unusual event. However, lymph node infarction should alert the pathologist to the considerable likelihood of malignant lymphoma. We report two unusual cases of acute myeloid leukemia presenting with granulocytic sarcoma at disease onset with a lymph node lesion exhibiting extensive lymph node infarction. The infarcted tissue contained numerous eosinophilic cell ghosts. There were some islands of degenerated, pyknotic medium-sized nuclei resembling lymphoblasts present in the necrotic area. By immunohistochemistry, these medium sized cells were CD3-, CD20-, CD34+, CD43+, CD45RO-, CD68-, CD79a- and myeloperoxidase+ in both cases. Differentiation of granulocytic sarcoma from malignant lymphomas is important for adequate therapy. The present cases indicate that granulocytic sarcoma should be added to the list of differential diagnoses for lymph node infarction. 相似文献
15.
Human herpesvirus 8 (HHV8) sequence variations in HHV8 related tumours in Okinawa, a subtropical island in southern Japan 总被引:2,自引:0,他引:2
Kamiyama K Kinjo T Chinen K Iwamasa T Uezato H Miyagi JI Mori N Yamane N 《Journal of clinical pathology》2004,57(5):529-535
BACKGROUND: Although rare in mainland Japan, classic Kaposi's sarcoma (KS) is frequently reported in Okinawa, a subtropical island in southern Japan. Human herpesvirus 8 (HHV8) has been identified in the tumours and geographical differences occur. Aim: To sequence HHV8 in classic and AIDS associated KS in Okinawa. MATERIALS/METHODS: Eight classic KS cases, one AIDS associated KS, five granuloma pyogenicum cases, two inflammatory pseudotumours, two Castleman's disease cases, one angiosarcoma, and one primary effusion lymphoma (PEL) were studied. As a control, HHV8 positive cultured PEL cells (TY-1) were used. The presence of HHV8 sequences was evaluated by PCR and in situ hybridisation. PCR products were sequenced. RESULTS: There were no histological differences among KS resulting from the different virus genotypes. HHV8 was detected in all cases of KS, in one PEL, and one granuloma pyogenicum. Eight classic KS cases and one granuloma pyogenicum were infected with HHV8 genotype II/C (K1 region) or subtype C (ORF26 region), which had a five amino acid deletion at K1 VR2 region. An AIDS associated KS and a PEL were infected with type I/A virus. CONCLUSION: In Okinawa, classic KS cases and one granuloma pyogenicum case were infected with HHV8 genotype II/C, also classified as subtype C. AIDS associated KS and PEL were infected with a different HHV8 (genotype I/A), similar to that found in the USA. In Okinawa, HHV8 infection is more than four times higher than in mainland Japan, resulting in many cases of KS because of HHV8 genotype II/C infection. 相似文献
16.
Fibronectin binds to C1q: possible mechanisms for their co-precipitation in cryoglobulins from patients with systemic lupus erythematosus 下载免费PDF全文
I Kono T Sakurai T Kabashima K Yamane H Kashiwagi 《Clinical and experimental immunology》1983,52(2):305-310
Fibronectin and C1q frequently co-precipitated in cryoglobulins from patients with SLE. As a portion of the C1q molecule is similar to collagen to which fibronectin has a high affinity, we studied whether fibronectin specifically bound to C1q. Fibronectin was found to bind to both native and heat-inactivated C1q. The binding was enhanced by Ca++ and low ionic strength. We have also demonstrated that fibronectin is capable of binding to C1q fixed to immune complexes. The interaction between fibronectin and C1q may play a role in cryoglobulin formation and in clearance of immune complexes by reticuloendothelial system. 相似文献
17.
Clinical Evaluation of the ASTY Colorimetric Microdilution Panel for Antifungal Susceptibility Testing 总被引:3,自引:2,他引:3 下载免费PDF全文
M. A. Pfaller S. Arikan M. Lozano-Chiu Y.-S. Chen S. Coffman S. A. Messer R. Rennie C. Sand T. Heffner J. H. Rex J. Wang N. Yamane 《Journal of clinical microbiology》1998,36(9):2609-2612
A method using a commercially prepared colorimetric microdilution panel (ASTY; Kyokuto Pharmaceutical Industrial Co., Ltd.) was compared in four different laboratories with the National Committee for Clinical Laboratory Standards (NCCLS) reference microdilution method by testing 802 clinical isolates of Candida spp. (C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. krusei, C. lusitaniae, C. guilliermondii, C. lipolytica, C. rugosa, and C. zeylanoides) against amphotericin B, 5-fluorocytosine (5FC), fluconazole, and itraconazole. Reference MIC endpoints were established after 48 h of incubation, and ASTY endpoints were established after 24 and 48 h of incubation. ASTY endpoints were determined to be the time at which the color of the first well changed from red (indicating growth) to purple (indicating growth inhibition) or blue (indicating no growth). Excellent agreement (within 2 dilutions) between the reference and colorimetric MICs was observed. Overall agreement was 93% at 24 h and 96% at 48 h. Agreement ranged from 90% with itraconazole and 5FC to 96% with amphotericin B at 24 h and from 92% with itraconazole to 99% with amphotericin B and 5FC at 48 h. The ASTY colorimetric microdilution panel method appears to be comparable to the NCCLS reference method for testing the susceptibilities of Candida spp. to a variety of antifungal agents. 相似文献
18.
Effects of adapting lights on the time course of the receptor potential of the anuran retinal rod. 总被引:2,自引:0,他引:2 下载免费PDF全文
1. The intracellular receptor potential of the retinal rod cell was recorded in the unperfused, isolated retina of Rana catesbiana and in the perfused, isolated retina of Bufo marinus. Qualitatively, the responses from the two preparations were similar. 2. The rate at which the receptor potential returned to the dark level at the termination of a pulse of light (Voff) was measured at a fixed potential chosen to be about 0-6 of the way from the dark level to the peak of the response. 3. When the light intensity was such that less than about 10-minus 5 of the photopigment was bleached per second, Voff increased as the duration of the pulse was increased, reaching a maximum in 50-100 s. 4. When a brief test flash was presented at various intervals after an adapting pulse lasting about 50 s, Voff for the test flash was greater than the value in the dark adapted state for times up to about 80 s after the adapting pulse. 5. It has been hypothesized that in the vertebrate rod light causes release from the disk sacs of particles which block conducting channels in the surface membrane (Yoshikami & Hagins, 1971, 1973). A modification is proposed in which the blocking particles are converted to an inactive state can be increased by light adaptation. 6. This modified hypothesis will account qualitatively for the further observations that (a) during the response to illumination lasting several seconds the membrane potential recovers part of the way to the dark level and (b) if a second light pulse is superimposed on this background illumination then after the superimposed pulse the depolarization is increased. 相似文献
19.
20.
Kojima M Nakamura S Shimizu K Hosomura Y Ohno Y Itoh H Yamane N Yoshida K Masawa N 《International journal of surgical pathology》2001,9(3):207-214
We report 11 Japanese cases of inflammatory pseudotumor (IPT) of the lymph node. There were 7 males and 4 females with ages ranging from 5 to 68 years (median; 48). Only 2 patients had systemic lymphadenopathy, and all others had involvement of only 1 lymph node group. Constitutional symptoms such as fever were present in 8 patients and laboratory abnormalities were detected in 5. All patients recovered and were alive and well after 2 to 180 months (median; 32 months). Histologically, the process mainly involved the connective tissue framework of the lymph node, secondarily spreading into the lymph node parenchyma and the perinodal tissue. It was characterized by a storiform growth pattern of myofibroblasts, marked vascularity with associated vascular lesions, and a polymorphous reactive cellular infiltrate in a collagen-rich stroma. An immunohistochemical study revealed numerous myofibroblasts, histiocytes, and vascular endothelial cells expressing vascular endothelial growth factor (VEGF) in 6 cases. It was suggested that VEGF may be involved, in part, in the induction of the angiogenesis of IPT. Moreover, the present study indicates that follicular dendritic cell sarcoma, nasal T/natural killer cell lymphoma, and anaplastic large cell lymphoma should be added to the differential diagnosis from IPT of the lymph node. Int J Surg Pathol 9(3):207-214, 2001 相似文献