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71.
Expression of Jun activation domain-binding protein 1 and p27 (Kip1) in thyroid medullary carcinoma 总被引:1,自引:0,他引:1
Ito Y Yoshida H Nakamura Y Tomoda C Uruno T Takamura Y Miya A Kobayashi K Matsuzuka F Kuma K Kakudo K Miyauchi A 《Pathology》2005,37(3):216-219
AIMS: p27 is a prominent regulator of cell proliferation by universally inhibiting the cell cycle, while Jun activation domain-binding protein 1 (Jab1), a multifunctional cell signaling protein, contributes to carcinoma progression by degrading p27. In this study, we investigated the expression of these proteins in medullary thyroid carcinoma. METHODS: We immunohistochemically examined Jab1 and p27 expression in 64 medullary thyroid carcinomas. RESULTS: Of the 64 cases examined, decreased p27 expression was observed in 38 cases (59.4%). The p27 expression level was inversely linked to tumour size as well as plasma calcitonin level. Jab1 expression level was generally high, and 46 cases (71.9%) were classified as overexpressing Jab1. The incidence was higher than those in papillary and follicular carcinomas, which were previously reported. Jab1 expression level was inversely linked to that of p27, and all five cases with only cytoplasmic but not nuclear staining of p27 overexpressed Jab1. CONCLUSIONS: These findings suggest that (1) decrease in p27 expression may contribute to local tumour growth; (2) Jab1 expression is related to the progression of medullary carcinoma by decreasing the amount of p27 in the cell and accelerating its degradation; and (3) Jab1 may play a more vital role in the pathogenesis of medullary carcinoma than papillary and follicular carcinomas. 相似文献
72.
Yamamoto K Okamura A Minagawa K Yakushijin K Urahama N Gomyo H Shimoyama M Itoh M Matsui T 《Cancer Genetics and Cytogenetics》2003,147(2):128-133
Follicular lymphoma is characterized genetically by t(14;18)(q32;q21), whereas t(18;22)(q21;q11), a rare variant form of t(14;18), has been preferentially observed in chronic lymphocytic leukemia (CLL). We describe here an unusual case of follicular lymphoma with a t(18;22)(q21;q11), that progressed to diffuse large cell lymphoma with a novel t(2;6)(p12;q23). Spectral karyotyping revealed that add(2)(p12) and add(6)(q23) were derived from a t(2;6)(p12;q23). Fluorescence in situ hybridization analysis confirmed rearrangements of the BCL2 gene at 18q21 and the BCL6 gene at 3q27. Our results indicate that a reciprocal translocation involving 6q23 could be implicated in the progression of follicular lymphoma and that t(18;22) may have a specific role in the pathogenesis of follicular lymphoma as well as CLL. 相似文献
73.
While tissue engineering has long been thought to possess enormous potential, conventional applications using biodegradable scaffolds have limited the field's progress, demonstrating a need for new methods. We have previously developed cell sheet engineering using temperature-responsive culture dishes in order to avoid traditional tissue engineering approaches, and their related shortcomings. Using temperature-responsive dishes, cultured cells can be harvested as intact sheets by simple temperature changes, thereby avoiding the use of proteolytic enzymes. Cell sheet engineering therefore allows for tissue regeneration by either direct transplantation of cell sheets to host tissues or the creation of three-dimensional structures via the layering of individual cell sheets. By avoiding the use of any additional materials such as carrier substrates or scaffolds, the complications associated with traditional tissue engineering approaches such as host inflammatory responses to implanted polymer materials, can be avoided. Cell sheet engineering thus presents several significant advantages and can overcome many of the problems that have previously restricted tissue engineering with biodegradable scaffolds. 相似文献
74.
Kawano Y Fukuda J Itoh H Takai N Nasu K Miyakawa I 《American journal of reproductive immunology (New York, N.Y. : 1989)》2004,52(2):124-128
PROBLEM: In order to investigate the role of macrophage colony-stimulating factor (M-CSF) and monocyte chemoattractant protein -1 (MCP-1) in human ovulation, we studied the regulation of M-CSF and MCP-1 in cultured human granulosa cells. METHOD OF STUDY: Immortalized granulosa cells (GC1a) were cultured in serum-free medium, and incubated with interleukin (IL)-1alpha, IL-1 receptor antagonist (ra) and tumor necrosis factor (TNF)-alpha. The supernatants were collected, and M-CSF and MCP-1 were measured by ELISA. RESULTS: The levels of M-CSF and MCP-1 were increased after treatment with IL-1alpha (1 nm) and TNF-alpha (1 nm) in a time-dependent manner. The levels of M-CSF and MCP-1 were significantly increased after treatment with IL-1alpha and TNF-alpha in a dose-dependent manner. However, the levels of M-CSF and MCP-1 were significantly decreased by treatment with IL-1alpha (1 nm) and/or increasing concentrations of IL-1 ra. CONCLUSIONS: Our data indicated that M-CSF and MCP-1 were regulated by IL-1alpha and TNF-alpha. It was suggested that M-CSF and MCP-1 may play an important role in human preovulatory processes. 相似文献
75.
Annexin V and propidium iodide (PI) staining is a general technique for detecting apoptosis by flow-cytometry (FCM). The release of 2',7'-bis-(2-carboxyethyl)-5- (and-6)-carboxyfluorescein (BCECF), a non-lipophilic membrane-impermeable labeling dye, from the cytoplasm of target cells is an indicator of increased membrane permeability. This study aimed to devise a three-color FCM technique involving the BCECF-release parameter in addition to conventional Annexin V and PI staining for the analysis of target K562 cells undergoing cytotoxic/apoptotic processes mediated by natural killer (NK) cells. The results demonstrated the following step-wise process of membrane impairment: (1) initiation of Annexin V staining accompanied by increasing forward scatter (FSC) before BCECF-release, indicating membrane impairment without permeabilization by necrosis; (2) BCECF-release with decreasing FSC before PI influx; and (3) PI staining with the lowest FSC state. Therefore, the early stage of cytotoxicity/apoptosis conventionally defined by the flow-cytometric criteria of Annexin V staining before PI staining could be sub-divided into two stages before and after BCECF-release. Annexin-V staining in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis was also initiated without BCECF-release. Although the underlying mechanism of the transition process from stage 1 to stage 2 is still unknown, this FCM technique should be a useful tool for differential assays of target cells regarding the sequential processes of NK-induced cytotoxicity. 相似文献
76.
Endo Y Yamauchi K Tsutsui Y Ishihara Z Yamazaki F Sagawa S Shiraki K 《The Japanese journal of physiology》2002,52(5):421-427
To investigate the possible involvement of the sympathetic nervous system in pressor response during water drinking, muscle sympathetic nerve activity (MSNA), blood pressure (BP), and heart rate (HR) were continuously measured in healthy young volunteers throughout the experiments of a 5-min control, 2 min of drinking 500 ml water, and a 28-min recovery. To avoid the effects of water passing through the oropharyngeal and esophageal regions and/or effects of swallowing, an equal amount of water was directly infused to the stomach through a stomach tube for 2 min. Water drinking caused a transient increase in mean arterial pressure (MAP) and HR immediately after drinking (DeltaMAP, 12.6 +/- 2.1 mmHg; DeltaHR, +19.9 +/- 1.7 beats/min at the peak). An abrupt decrease of MSNA was observed directly during water drinking (Deltaburst rate, -6.9 +/- 1.3 bursts/min; Deltatotal activity, -2,606 +/- 491 U/min), and it increased to the baseline level thereafter. Gastric infusion had little or no effect on MAP, HR, and MSNA. The present study demonstrated that a pressor response during water drinking was associated with the attenuation of MSNA and not generated by gastric infusion of water at the same rate as in this drinking manner. In conclusion, the rapid rise in BP might be caused through stimulations from the oropharyngeal region, swallowing-induced factors, and/or a feedforward mechanism by a central descending signal from the higher brain centers. 相似文献
77.
H Doi S Nakagawa K Nagata M Hata S Kasahara T Sakata R Suzuki M Nanno K Sugamura T Itoh 《European journal of immunology》1991,21(3):783-792
To investigate the role of thymic nurse cells (TNC) in activation and differentiation of fetal CD4-CD8- (double-negative) thymocytes, we have co-cultured murine fetal thymocytes (14-15 days of gestation) with an established murine TNC clone. We show here that TNC induced the growth of the fetal double-negative thymocytes in the presence of recombinant interleukin 2 (rIL2). Activated fetal thymocytes markedly formed lymphocyte-TNC complexes and proliferated extensively after 5 days in the co-culture. The activated fetal thymocytes in this co-culture condition remained double negative after 10 days in culture. None of them gave rise to phenotypically and functionally competent lymphocytes during this period. TNC alone and the supernatant of TNC had no effect on activation. The presence of both TNC and rIL2 was necessary for the growth of fetal thymocytes in our system. The proliferation of fetal thymocytes was inhibited by a monoclonal antibody against mouse IL2 receptors (IL2R). The fetal thymocytes could be maintained further in this co-culture condition. The prolonged cultivation of fetal thymocytes resulted in the establishment of the fetal thymocyte line and its several clones. CD4 single-positive cells of activated fetal thymocytes first appeared 14 days after the onset of culture and their number increased, whereas CD8+ cells or CD4CD8 double-positive cells were not observed. These results indicate that fetal CD4-CD8- thymocytes underwent phenotypic change after long periods of culture. All established clones of fetal thymocytes are CD4 single positive showing lymphocyte-TNC interactions but do not express CD3 complex. Northern blot analysis detected mRNA for the gamma T cell receptor, but no messages for the delta, alpha or beta T cell receptor. Chemical cross-linking of 125I-labelled IL2 revealed that the 90-kDa band (presumably considered to be the IL2R beta chain) was clearly present in IL2-responsive fetal clones, whereas freshly isolated day 14-15 fetal thymocytes lacked the band. Taken together, TNC might be involved in the differentiation and/or expansion of murine fetal thymocytes by inducing IL2R beta chain, which forms the functional IL2R together with IL2R alpha chain and CD4, one of the T cell accessory molecules, on the cell surface through direct cell-cell interaction. 相似文献
78.
Contamination of transplantable human tumor-bearing lines by Helicobacter hepaticus and its elimination
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Goto K Ishihara KI Kuzuoka A Ohnishi Y Itoh T 《Journal of clinical microbiology》2001,39(10):3703-3704
Helicobacter hepaticus contaminating nonfrozen tumors was transmissible to severe combined immunodeficient (SCID) mice, but the organism in cryopreserved samples was not. This suggests that H. hepaticus has the ability to spread via biomaterials and that freezing-thawing is able to reduce the numbers of organisms to levels insufficient for subcutaneous infection of SCID mice. 相似文献
79.
The ultrasound examination of the deep vein thrombosis 总被引:2,自引:0,他引:2
Taniguchi N Ono T Itoh K 《Rinsho byori. The Japanese journal of clinical pathology》2003,51(8):761-769
Ultrasonography is very useful for detection of deep vein thrombosis. The purpose of this paper is to show a method for detecting them efficiently by high resolution transducer and color Doppler system. We examined patients in the supine and prone positions. To detect the venous flow easily and differentiate thrombi from simple venous dilatation, some maneuvers are useful; one is pushing the vein area using the transducer on examination, the second is breathing overload, and the last is so-called milking. We can find throombi in the external iliac or femoral veins of patients who have symptoms of lower leg swelling, however, we need to better detect venous thrombi in the lower leg in patients with a history of pulmonary embolism. Because deep venous thrombi are increasing, the role of ultrasound will expand in the future. 相似文献
80.
Pathogenesis of Rinderpest Virus Infection in Rabbits I. Clinical Signs, Immune Response, Histological Changes, and Virus Growth Patterns
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Kazuya Yamanouchi Fumitoshi Chino Fumio Kobune Akiko Fukuda Yasuhiro Yoshikawa 《Infection and immunity》1974,9(2):199-205
Rabbits were intravenously inoculated with an attenuated rinderpest virus (L strain), and general patterns of the disease were investigated. The rabbits developed fever with concomitant occurrence of diarrhea and lymphopenia. Early production of interferon was followed by a rise of neutralizing antibody. Histological examinations revealed an involvement of all of the lymphoid tissues, with primary lesions consisting of necrosis of the lymphoid follicles and formation of giant cells. Immunofluorescent examinations suggested that the virus growth was present in almost all of the lymphoid tissues. The possibility of application of this experimental system for the study of systemic infection by measles virus was discussed. 相似文献