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41.
Kenichiro Karasawa Nobuo Sugiura Yusuke Hori Sakaru Suzuki Junichi Onaya Katsukiyo Sakurai Koji Kimata 《Clinical & experimental metastasis》1997,15(2):83-93
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis. 相似文献
42.
Functional tyrosine kinase inhibitor profiling: a generally applicable method points to a novel role of platelet-derived growth factor receptor-beta in tuberous sclerosis 总被引:1,自引:0,他引:1 下载免费PDF全文
Arbiser JL Govindarajan B Bai X Onda H Kazlauskas A Lim SD Amin MB Claesson-Welsh L 《The American journal of pathology》2002,161(3):781-786
A ubiquitous herpesvirus that establishes life-long infection, the Epstein-Barr virus (EBV) has yielded little insight into how a single agent in general accord with its host can produce diverse pathologies ranging from oral hairy leukoplakia to nasopharyngeal carcinoma, from infectious mononucleosis to Hodgkin's disease (HD) and Burkitt's lymphoma. Its pathogenesis is further confounded by the less than total association of virus with histologically similar tumors. In other viral systems, defective (interfering) viral genomes are known to modulate outcome of infection, with either ameliorating or intensifying effects on disease processes initiated by prototype strains. To ascertain whether defective EBV genomes are present in HD, we examined paraffin-embedded tissue from 56 HD cases whose EBV status was first determined by cytohybridization for nonpolyadenylated EBV RNAs (EBERs). Using both standard polymerase chain reaction (PCR) and PCR in situ hybridization, we successfully amplified sequences that span abnormally juxtaposed BamHI W and Z fragments characteristic of defective heterogeneous (het) EBV DNA from 10 of 32 (31%) EBER-positive tumors. Of 24 EBER-negative HD, 8 yielded PCR products indicating presence of het EBV DNA. Two of these contained defective EBV in the apparent absence of the prototype virus. Of the 42 tumors analyzed for defective EBV by both PCR techniques, there was concordance of results in 38 (90%). Detection of defective EBV genomes with the potential to disrupt viral gene regulation suggests one mechanism for pathogenic diversity that may also account for loss of prototypic EBV from individual tumor cells. 相似文献
43.
Hiroaki Nakamura 《Developmental dynamics》1988,181(4):406-418
Prenatal development of the thoracic aorta of the rat during the period ranging from gestational days 12 to 21 was examined by transmission electron microscopic and morphometric studies. The process of wall formation occurred in four major phases. At phase I (gestational day 12), the dorsal aorta consists of an endothelium and loosely surrounding mesenchymal cells. Collagen fibrils and fine filamentous materials are sparsely present in the intercellular space. At phase II (days 13 to 16), the mesenchymal cells begin to differentiate to myoblasts, which have small clusters of myofilaments with dense bodies, rough endoplasmic reticulum, and a discontinuous basal lamina. The differentiating cells form a few compact cell layers around the endothelium. Elastic fibers first occur sparsely in juxtacellular spaces at days 13–14. The thickness of the aorta increases rapidly from 1–3 layers of cells at day 13 to 5–8 layers at day 17, leading to a maximum of 5–9 cell layers at day 20. The differentiation of myoblasts and elastogenesis are initiated in the inner layers, and later progress toward the outer layer of the aortic wall. At phase III (days 17 to 19), the myoblasts continue to develop into typical smooth muscle cells, and elastic fibers rapidly increase in both size and number. At phase IV (day 20 and later), smooth muscle cells have well-developed myofilaments in the cell periphery, and rough endoplasmic reticulum and other organelles tend to accumulate in the apical portion of the cytoplasm. Elastic laminae appear in a few inner layers of the aortic wall. 相似文献
44.
Takaaki Ohmori Kazuyo Okada Ryo Tabei Keisuke Sugiura Shinji Nabeshima Hiroji Ohoka Masaki Okamoto 《Pathology international》1994,44(4):333-337
A case of primary seminal vesicle carcinoma is reported. The tumor was a CA125-producing adenocarcinoma consisting of fine papillary-tubular, intricate branching or anastomosing glandular structures and was composed of small cuboidal, but occasionally hobnailed, cells with mostly clear, but occasionally granular, cytoplasm. Some tumor cells showed evidence of secretion of seromucinous materials into the interpapillary and cystic space. lmmunohistochemically, almost half of the tumor cells expressed a positive reaction with anti-CAl25, a common serological marker for ovarian epithelial carcinomas; however, no tumor cells expressed any other serological tumor markers such as carcinoem-bryonic antigen, α-fetoprotein, human chorionic gonadotropin, prostatic specific acid phosphatase, or prostatic specific antigen. The patient showed a high level of serological CA125, which fluctuated parallel with the growth, removal and recurrence of the tumor. The morphological and immunohistochemical findings suggested a close relationship between the present tumor and clear cell carcinoma of the ovary, which is thought to be of a Müllerian-Wolfian duct origin. 相似文献
45.
46.
Summary We have compared the kinetic growth patterns of To-336, MEQ11, KRT, and SK2 rubella vaccine strains licensed in Japan at 37° and 39° C with those of progenitor wild strains of rubella virus. The growth of vaccine strains was depressed at 39° C to a level about 3 log10 lower than that at 37° C. The difference in virus titer attained by wild strains at 37° and 39° C was less than tenfold. The growth potential at 39° C paralleled the immunogenic marker of rubella virus,i.e. the capability of virus to induce antibody response upon subcutaneous injection in rabbits for all wild and vaccine strains examined, including one strain at an intermediate level of attenuation. Several clones were isolated from the progeny produced by a vaccine strain during the growth at 39° C. Among them were partial revertants in immunogenic marker as well as in the growth potential at 39° C. It was concluded that the immunogenic marker of rubella virus in rabbits represented its capability to replicate at the body temperature of the animal.With 6 Figures 相似文献
47.
Shunsuke Imai Susumu Sekigawa Hiroaki Yamamoto Yoshihiko Tsubura Michiyo Miyanaga Nobuhiro Narita Riichiro Mikami 《Pathology international》1982,32(4):677-682
An autopsy case of bronchiolo-alveolar adenocarcinoma in the lung is reported. The patient is a 70-year-old male who complained of severe cough with 500–600 ml watery sputum a day, loss of weight, and general fatigue. Autopsy revealed numerous whitish tumors in various sizes with multiple cysts in both lungs, with no metastasis being found in any other organs. Histological findings identified the tumor as a bronchiolo-alveolar adenocarcinoma originating from the lungs. Electron-microscopic findings showed that the tumor cells were covered by prominent microvilli, and contained abundant irregulary-shaped cytoplasmic vacuoles suggestive of mucin. 相似文献
48.
49.
Susumu Harada Maya Iijima Akiko Nakamura Yoshitsugu Yoshizaki Hiroaki Matsuo Eisin Morita 《Arerugī》2007,56(1):41-48
BACKGROUND: Either omega-5 gliadin or high molecular weight glutenin is known to be a major allergen in wheat-dependent exercise-induced anaphylaxis (WDEIA). It is generally considered that gluten specific IgE score is more reliable than that of wheat specific IgE score for the diagnosis of WDEIA. Our aim was to verify the significance of gluten specific IgE in the diagnosis of WDEIA. METHODS: We evaluated the result of gluten CAP-RAST score and omega-5 gliadin specific IgE score on four WDEIA patients who visited our hospital during the years 2004 and 2005, whose diagnosis were onfirmed by prick tests, immunoblot tests and provocation tests. RESULTS: Contrary to our expectations, all four patients showed negative gluten CAP-RAST scores, however all patient's omega-5 gliadin specific IgE scores were positive. CONCLUSION: Our results suggest that gluten specific CAP-RAST score is unreliable in the diagnosis of WDEIA. On the other hand omega-5 gliadin specific IgE score is possibly a better candidate as a diagnostic tool for WDEIA. 相似文献
50.
Koebner phenomenon in lupus erythematosus with special consideration of clinical findings 总被引:1,自引:0,他引:1
Ueki H 《Autoimmunity reviews》2005,4(4):219-223
The isomorphic response of Koebner can be observed not only in psoriasis, but also in other diseases, such as lichen planus and some systemic diseases including LE (lupus erythematosus) or sarcoidosis. Several clinical findings in LE skin were presented and discussed in this review. The mutually-interactive-, negative-, and internal-Koebner phenomena were introduced and discussed with some speculative views. Many forms of environmental stress on the skin were reported as provocating factors of the Koebner phenomenon, including trauma, scratching, UV-exposure, and various types of dermatitis. Clinical observations of the nature, localization, and movement of lesions should be carefully made. The pathophysiology of the Koebner phenomenon may be classified into two steps. A first non-specific inflammatory step and a second disease-specific step. The inflammatory products released from the first step would be targeted in the second step. In the first step, there could be many substances including cytokines, stress proteins, adhesion molecules, or autoantigens translocated from intra-cellular areas. In the second step after latent periods, there may be disease-specific reactions, including ones by T-cells, B-cells, autoantibodies, and immune deposits, under the restriction of genetic backgrounds. The Koebner phenomenon may prove useful in understanding the pathophysiology of diseases of unknown origin. 相似文献