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81.
Immunohistochemical,ultrastructural and biochemical studies of an amylase-producing breast carcinoma
Hideo Inaji Hiroki Koyama Masahiko Higashiyama Shinzaburo Noguchi Hitoshi Yamamoto Osamu Ishikawa Kaoru Omichi Takeshi Iwanaga Akira Wada 《Virchows Archiv : an international journal of pathology》1991,419(1):29-33
Summary We describe a breast cancer with ectopic production of amylase, found in the patient's serum, urine and in the tumour. Clinically, serum amylase levels reflected both the progression of the disease and regression induced by various therapies. Using agarose gel electrophoresis and a wheat protein inhibitor assay, the predominant serum amylase appeared to be identical to pancreatic-type isoenzyme. However, the action mode analysis using a new fluorogenic substrate revealed that the serum contained non-salivary, non-pancreatic amylase. The tumour had microscopic features of invasive ductal carcinoma with some argyrophilic differentiation. The component cells stained positively for amylase, and ultrastructurally numerous secretory granules were seen. 相似文献
82.
Shimoya K Moriyama A Ogata I Nobunaga T Koyama M Azuma C Murata Y 《Molecular human reproduction》2000,6(9):829-834
Secretory leukocyte protease inhibitor (SLPI) is a potent inhibitor of human leukocyte elastase. We investigated whether SLPI was present in the peritoneal fluid of women with endometriosis and to clarify the role of SLPI in the pathogenesis of endometriosis. Western blot analyses revealed that SLPI protein was detected as a 12 kDa band in peritoneal fluid. The peritoneal fluid concentrations of SLPI, elastase and interleukin-6 were assayed by enzyme-linked immunosorbent assays (ELISA). SLPI concentrations and the SLPI/elastase ratio in the peritoneal fluid of women with endometriosis were higher than in samples from women without endometriosis. There was no significant correlation between concentrations of SLPI and interleukin-6 in the peritoneal fluid. Immunohistochemistry using an anti-SLPI polyclonal antibody revealed positive staining in peritoneal macrophages, but not lymphocytes. The present findings suggest that SLPI found in the peritoneal fluid of patients with endometriosis may contribute to the pathogenesis of endometriosis. 相似文献
83.
84.
Hisao Yamaguchi Junya Fukuda Kensuke Baba Hiroshi Takeuchi Keizo Kageyama 《Pathology international》1972,22(3):427-440
The vascular structures in the lymph node and their relation to fluid exchange have been reported in previous communications and it was considered that the morphological changes of the vascular structures were closely correlated with the functional development of lymph nodes as an antibody forming organ. In order to clarify the localization of the given antigen and newly formed antibody in relation to the morphological structure of lymph nodes, the popliteal lymph nodes of rabbits were studied by immuno-fluorescent techniques.
The antibody was found in the pavement arrangement (solid) of reticulum tissue which was formed by the expel of lymphocytes in the cortical mass and by the morphofunctional alterations of the reticulum cells. The given antigen and newly formed antibody were never detected in the follicles throughout the period of this experiment. ACTA PATH. JAP. 22:427–440, 1972. 相似文献
The antibody was found in the pavement arrangement (solid) of reticulum tissue which was formed by the expel of lymphocytes in the cortical mass and by the morphofunctional alterations of the reticulum cells. The given antigen and newly formed antibody were never detected in the follicles throughout the period of this experiment. ACTA PATH. JAP. 22:427–440, 1972. 相似文献
85.
Implantation study of a novel hydroxyapatite/collagen (HAp/col) composite into weight-bearing sites of dogs 总被引:2,自引:0,他引:2
Itoh S Kikuchi M Takakuda K Nagaoka K Koyama Y Tanaka J Shinomiya K 《Journal of biomedical materials research》2002,63(5):507-515
A hydroxyapatite/type I collagen (HAp/Col) composite, aligning hydroxyapatite nanocrystals along collagen molecules, has been prepared. The biocompatibility, osteoconductive activity, and efficacy as a carrier of rhBMP-2 of this novel biomaterial implanted in the weight-bearing site have been examined. The HAp/Col implants (15 mm in diameter and 20 mm in length) with a surface cross-linked layer containing rhBMP-2 (0 or 400 microg/ml) were implanted into bone defects of tibiae in three beagle dogs and fixed according to the Ilizarov method. As a control, bone defects of 20 mm in two beagle dogs did not receive implants, and the dogs were allowed to walk using an Ilizarov extraskeletal fixator. The specimens were removed from one dog in each group after 12 weeks. Also, the Ilizarov fixators in the rhBMP-treated dogs were removed after 12 weeks, after which full weight bearing started. The specimens were further taken out after 18 and 24 weeks in the rhBMP-treated and non-rhBMP-treated dogs, and after 24 weeks in the control group. The change of bone mineral density, as well as radiological and histological findings, suggest that the implants are able to induce bone remodeling units and are a superior carrier of rhBMP-2 due to the stimulation of early callus and new bone formation. 相似文献
86.
As demonstrated by others, diisopropyl fluorophosphate (DFP) markedly inhibits the O2- generation from guinea-pig polymorphonuclear leukocytes (PMN) stimulated by an antibody complex with ovalbumin (Ag-Ab complex), and also the intracellular uptake of antibody-sensitized erythrocytes by the cells. However, when PMN were treated with DFP and washed to remove the inhibitor, they again became able to exhibit the O2- -generating and phagocytic activities. The [3H]DFP-labeling of intact PMN followed by solubilization with Triton N101, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed the existence of several [3H]DFP-labeled proteins with different mol. wts, which disappeared on pretreatment of cells with cold DFP. However, stimulation of DFP-pretreated PMN with Ag-Ab complex in the presence of [3H]DFP resulted in the appearance of a [3H]DFP-labeled, membrane-bound protein with a mol. wt of 40,000. This protein was isolated by affinity chromatography of the solubilized PMN and phagosomes on anti-Ig antibody-Sepharose 4B. Although the enzymatic properties of the protein are not clear, the results so far obtained suggest that it is a putative, stimulus-activated serine protease participating in the triggering events leading to the activation of NADPH oxidase responsible for the respiratory burst and the formation of phagosomes. 相似文献
87.
Influenza virus overcomes apoptosis by rapid multiplication 总被引:1,自引:0,他引:1
Kurokawa M Koyama AH Yasuoka S Adachi A 《International journal of molecular medicine》1999,3(5):527-530
The kinetics of apoptotic fragmentation of the chromosomal DNA was determined in the influenza virus-infected MDCK, HeLa and KB cells, respectively. Comparison of these kinetics with the kinetics of virus multiplication revealed that the multiplication of influenza virus was observed only when apoptosis was induced after the production of progeny virus in the infected cells. The extent of apoptotic response was reversely correlated with the permissiveness of the cells. 相似文献
88.
Tissue regeneration using macrophage migration inhibitory factor-impregnated gelatin microbeads in cutaneous wounds 下载免费PDF全文
Zhao Y Shimizu T Nishihira J Koyama Y Kushibiki T Honda A Watanabe H Abe R Tabata Y Shimizu H 《The American journal of pathology》2005,167(6):1519-1529
Migration inhibitory factor (MIF) responds to tissue damage and regulates inflammatory and immunological processes. To elucidate the function of MIF in cutaneous wound healing, we analyzed MIF knockout (KO) mice. After the excision of wounds from the dorsal skin of MIF KO and wild-type (WT) mice, healing was significantly delayed in MIF KO mice compared to WT mice. Lipopolysaccharide treatment significantly increased [(3)H]thymidine uptake in WT mouse fibroblasts compared to MIF KO mouse fibroblasts. Furthermore, there was a significant reduction in fibroblast and keratinocyte migration observed in MIF KO mice after 1-oleoyl-2-lysophosphatidic acid treatment. We subsequently examined whether MIF-impregnated gelatin slow-release microbeads could accelerate skin wound healing. Injection of more than 1.5 microg/500 microl of MIF-impregnated gelatin microbeads around a wound edge accelerated wound healing compared to a single MIF injection without the use of microbeads. MIF-impregnated gelatin microbeads also accelerated skin wound healing in C57BL/6 mice and diabetic db/db mice. Furthermore, incorporating MIF-impregnated gelatin microbeads into an artificial dermis implanted into MIF KO mice accelerated procollagen production and capillary formation. These findings suggest that MIF is crucial in accelerating cutaneous wound healing and that MIF-impregnated gelatin microbeads represent a promising treatment to facilitate skin wound healing. 相似文献
89.
Y Aratani F Kura H Watanabe H Akagawa Y Takano K Suzuki M C Dinauer N Maeda H Koyama 《Medical mycology》2002,40(6):557-563
Generation of oxidative products by phagocytic cells is known to be an important host defense mechanism directed toward killing of invading microorganisms. The importance of two major oxidant-producing enzymes, myeloperoxidase (MPO) and NADPH-oxidase, in in vivo fungicidal action was directly compared in genetically engineered mice. Both MPO-deficient (MPO-/-) and NADPH-oxidase-deficient (X-linked chronic granulomatous disease [X-CGD]) mice showed increased susceptibility to pulmonary infections with Candida albicans and Aspergillus fumigatus compared with normal mice, and the X-CGD mice exhibited shorter survivals than MPO-/- mice. This increased mortality of X-CGD mice was associated with a 10- to 100-fold increased outgrowth of the fungi in their organs during the first 6 days. These results suggest that superoxide (O2-) produced by NADPH-oxidase is more important than hypochlorous acid (HOCl) produced by MPO, although both oxidative products obviously contribute to the host defense against pulmonary infection with those fungi. We also observed that MPO-/-/X-CGD double knockout mice showed comparable levels of susceptibility to the X-CGD mice against C. albicans and A. funigatus, indicating that MPO is unable to play a role in host defense in the absence of NADPH-oxidase. This strongly suggests that hydrogen peroxide, the precursor of HOCl, is solely derived from O2- produced by NADPH-oxidase. 相似文献
90.
S Koyama 《The Japanese journal of physiology》1985,35(3):513-523
The present study was designed to determine effect of the preganglionic splanchnic nerve activity (SNA) on the brief hypotension accompanied with the occlusion of left circumflex coronary artery (CxCAO) in chloralose anesthetized cats. Following CxCAO in animals with neuraxis intact, no significant alterations of SNA occurred despite the significant fall in mean blood pressure (MBP). A significant fall in MBP also occurred in vagotomized animals with arterial baroreceptors intact, but SNA was significantly augmented from 12.9 +/- 2.7 impulses/sec before CxCAO to 24.4 +/- 4.3 impulses/sec 60 sec after the occlusion. In vagotomized animals, in which their carotid sinuses were isolated and perfused with the constant pressure at a level equal to systemic blood pressure (112 +/- 6 mmHg) and with higher pressure (167 +/- 7 mmHg), SNA was not altered significantly during the hypotension due to CxCAO. When the carotid sinuses were perfused with lower pressure (53 +/- 8 mmHg), a significant increase in SNA occurred simultaneously with the decrease in MBP after CxCAO. The peak decreases in blood pressure during the coronary occlusion were significantly greater in the vagotomized group (-46 +/- 5 mmHg) and in the Low-CSP group (-50 +/- 5 mmHg) than in other groups. Onset of this excitatory efferent sympathetic response to the hypotension due to the coronary occlusion in the vagotomized and Low-CSP groups was delayed significantly despite a significant fall in arterial blood pressure. These results show that vagal afferents from the heart may play a role of inhibiting the sympathetic augmentation mediated by arterial baroreceptors during cardiogenic hypotension. An excessive activation of cardiac receptors with sympathetic afferents may be induced by the profound fall in blood pressure, resulting in further impairment of cardiac function due to progressive myocardial ischemia under the condition of high sympathetic tone activated by baroreceptor reflex. 相似文献