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81.
Ochiai H Ohtsu T Tsuda T Kagawa H Kawashita T Takao S Tsutsumi A Kawakami N 《Acta medica Okayama》2005,59(1):27-32
On February 13, 2002, a public health center in Hiroshima Prefecture, Japan, was notified that many individuals living at the Japan Maritime Self-Defence Force base had symptoms resembling those of food poisoning. Self-administered questionnaires requesting information regarding meal consumption and symptoms were distributed to all 281 members at the base. A case of the illness was defined as a member who had had watery or mucousy stool, or loose stool with abdominal cramps, more than twice a day after consuming dinner on February 12. Control of the illness was defined as a member with no symptoms. The dinner on February 12 was significantly associated with the illness (Mantel-Haenszel odds ratio: 3.59, 95% confidence interval: 1.06-12.20). A case-control study showed that, among the food supplied at dinner on February 12, the braised chop suey was significantly associated with the illness (odds ratio: 12.30, 95% confidence interval: 1.90-521.00). The braised chop suey had been stored in a chafing dish. An environmental investigation indicated that Clostridium perfringens (C. perfringens) in the chafing dish proliferated under an inappropriate heat-retention temperature, and the contaminated braised chop suey could have caused the food poisoning. This study demonstrated that the recommended heat-retention temperature (over 65 degrees C) should be confirmed thoroughly. 相似文献
82.
83.
Sasaki K Kato M Takahashi T Ochi S Ichinose Y Shiraki K Asano Y Iwanaga M Tsuji T 《Journal of medical virology》2003,70(2):329-335
This study was undertaken to determine whether the specific Th1- or Th2-cell response to varicella-zoster virus was induced predominantly by a mucosal adjuvant, cholera toxin, in mice. A commercially available live varicella vaccine (Oka strain) and cholera toxin or its B subunit were administered simultaneously via the nasal route. Delayed-type hypersensitivity to the Oka vaccine was induced, but the systemic neutralizing antibody response was low. The delayed-type hypersensitivity evoked after a single administration was relatively higher than that on administration three times. When spleen cells from mice immunized once with the vaccine and cholera toxin or its B subunit were restimulated with the live vaccine in vitro, there was greater thymidine uptake and production of interleukin- 2 (IL-2) than controls, but only a low level of IL-4 production. The production of IL-2 induced by the B subunit of cholera toxin was less than that by cholera toxin and a mutant of Escherichia coli enterotoxin on co-immunization with the vaccine in mice. Cholera toxin and its B subunit have been reported to induce predominantly a specific Th2-type T-cell response to various antigens. However, the Oka vaccine is an antigen that polarizes the activation of specific Th1/Th2-type T cells by cholera toxin or its B subunit to the Th1-type side. Cholera toxin and its B subunit are thus useful mucosal adjuvants for inducing cellular immunity to the Oka vaccine similar to Escherichia coli enterotoxin. 相似文献
84.
85.
Intramembranous fine deposit disease associated with collagen disorders: a new morphological entity?
Hiroshi Sato Takao Saito Kaoru Yoshinaga 《Virchows Archiv : an international journal of pathology》1992,420(5):447-451
Summary A distinct, hitherto unknown renal histopathological appearance, consisting of diffuse thickening of the glomerular basement membrane (GBM) with fine intramembranous electron-dense deposits, was observed in the renal biopsies from three patients with collagen diseases. In each case, proteinuria was mild with normal urinary sediment. On light microscopy there were no particular abnormalities but a mild thickening of the glomerular capillary wall. Immunofluorescence studies revealed faint linear or extremely fine granular IgG deposition along the capillary wall. On electron microscopy, the GBM was diffusely thickened with fine intramembranous electron-dense deposits without spike formation. No other deposits were seen in the glomerulus. These histological features resembled those of membranous glomerulonephritis (MGN), although the possibility of the early change of MGN is excluded by specific findings in these cases. Other GBM-thickening diseases such as diabetic glomerulosclerosis were ruled out clinically and histologically. Our cases have a singular renal histopathology which differs from any of the previously established classifications of glomerular lesions. It may be a specific change associated with some type of collagen disease. 相似文献
86.
Li N Nakamura K Jiang Y Tsurui H Matsuoka S Abe M Ohtsuji M Nishimura H Kato K Kawai T Atsumi T Koike T Shirai T Ueno H Hirose S 《Human molecular genetics》2004,13(2):171-179
Systemic lupus erythematosus (SLE), a complex multigenic disease, is a typical antibody-mediated autoimmune disease characterized by production of autoantibodies against a variety of autoantigens and immune complex-type tissue inflammation, most prominently in the kidney. Evidence suggests that genetic factors predisposing to aberrant proliferation/maturation of self-reactive B cells initiate and propagate the disease. In SLE-prone New Zealand Black (NZB) mice and their F1 cross with New Zealand White (NZW) mice, B cell abnormalities can be ascribed mainly to self-reactive CD5+ B1 cells. Our genome-wide scans to search for susceptibility genes for aberrant activation of B1 cells in these mice showed evidence that the gene, Ltk, encoding leukocyte tyrosine kinase (LTK), is a possible candidate. LTK is a receptor-type protein tyrosine kinase, belonging to the insulin receptor superfamily, and is mainly expressed in B lymphocyte precursors and neuronal tissues. Sequence and functional analyses of the gene revealed that NZB has a gain-of-function polymorphism in the LTK kinase domain near YXXM, a binding motif of the p85 subunit of phosphatidylinositol 3-kinase (PI3K). SLE patients also had this type of Ltk polymorphism with a significantly higher frequency compared with the healthy controls. Our findings suggest that these polymorphic LTKs cause up-regulation of the PI3K pathway and possibly form one genetic component of susceptibility to abnormal proliferation of self-reactive B cells in SLE. 相似文献
87.
B cell development is perturbed in bone marrow from c-fos/v-jun doubly transgenic mice 总被引:2,自引:0,他引:2
Fujita Kenji; Miki Nobuhiko; Mojica Mariluz P.; Takao Shintaro; Phuchareon Janyaporn; Nishikawa Shin-Ichi; Sudo Tetsuo; Tokuhisa Takeshi 《International immunology》1993,5(2):227-230
c-fos and c-jun gene products form a heterodimeric complex (AP-1)that regulates target gene expression by binding to a specificDNA sequence motif. In order to study a role of AP-1 (Fos/Jun)in growth and differentiation of immature B lineage cells, wehave established and mated two independent transgenic mice carryingthe mouse c-fos gene or the viral v-Jun gene fused to the H-2Kpromoter. IL-7 dependent bone marrow cell culture from doublytransgenic (H2-fos/jun) mice demonstrated severe delay of earlyB cell development. Proliferation of pre-B cells in the freshbone marrow from HZ-fos/jun mice to IL-7 stimulation was verylow. These results suggest that the deregulated production ofAP-1 perturbs IL-7 mediated proliferation and differentiationof immature B cells. 相似文献
88.
Takao Hijikata Hitoshi Wakisaka Shumpei Niida 《Anatomical record (Hoboken, N.J. : 2007)》1993,236(4):602-610
Using digital image analysis and several anatomical methods, morphometric analysis of nonspanning fibers which had tapering profiles at their intrafascicular termination sites and represented overlapping arrangements within the fiber fascicles was performed in the rat rectus abdominis. Special emphasis was focused on dimensional relationships occurring between overlapping portions and tapering segments and sarcomere lengths in non- and overlapping portions. Nonspanning fibers were found to overlap each other for more than 40% of their length. In length, their overlapping portions generally corresponded to their tapering segments, which were also greater than 40% of the fiber length. In addition, despite the presence of overlapping linkages, nonspanning fibers maintained a fairly uniform length irrespective of their overlapping and non-overlapping portions. Overlapping linkages in fibers without tapering profiles have a larger cross-sectional area in the overlapping portion than in the non-overlapping one, resulting in a phenomenon which will cause different sarcomere lengths between the two portions during fiber stretching. The present results suggest that tapering profiles in the overlapping portion ensure uniform sarcomere lengths within nonspanning fibers, thereby providing mechanical stability in each fiber. © 1993 Wiley-Liss, Inc. 相似文献
89.
Arpp,a new homolog of carp,is preferentially expressed in type 1 skeletal muscle fibers and is markedly induced by denervation 总被引:3,自引:0,他引:3
Tsukamoto Y Senda T Nakano T Nakada C Hida T Ishiguro N Kondo G Baba T Sato K Osaki M Mori S Ito H Moriyama M 《Laboratory investigation; a journal of technical methods and pathology》2002,82(5):645-655
In this study, we isolated and characterized a murine counterpart of the human Arpp (hArpp) gene. Sequence analysis revealed that the murine Arpp (mArpp) gene is almost identical to the Ankrd2 gene, which has recently been isolated as a mouse gene induced in stretched skeletal muscle. The mArpp gene encodes a protein of 332 amino acids that contains four well-conserved ankyrin-repeat domains in the central portion of the protein. The amino acid sequence of mArpp protein (mArpp) is highly homologous to that of mouse cardiac-restricted ankyrin-repeat protein (Carp), which is proposed to be a putative genetic marker for cardiac hypertrophy. Immunohistochemical analysis revealed that mArpp is preferentially expressed in type 1 skeletal muscle fibers, and that mArpp is localized in both the nucleus and the sarcomeric I-band of muscle fibers, suggesting that Arpp may function as a nuclear and sarcomeric protein. Furthermore, mArpp was also expressed in neurons of the cerebellum and cerebrum, the islets of Langerhans in the pancreas, and the esophageal epithelium, suggesting that mArpp may play a functional physiologic role in brain, pancreas, and esophagus as well as in type 1 muscle fibers. Interestingly, although mArpp was localized in both nucleus and cytoplasm in neurons, its localization was restricted to nucleus in pancreas and esophagus, suggesting that intracellular localization of mArpp is regulated in a tissue-specific manner. Furthermore, we found that mArpp- and Carp-expression in skeletal muscle were markedly up-regulated after denervation. Although the elevated expression level of Carp was kept only for two weeks after denervation, that of Arpp was kept at least for 4 weeks, suggesting that mArpp and Carp may play distinct functional roles in denervated skeletal muscle. 相似文献
90.
Suguru Yonezawa Yoshifumi Matsushita Hisako Muramatsu Yuko Arita Takao Nakamura Takashi Muramatsu Eiichi Sato 《Pathology international》1987,37(8):1249-1261
Using the surgically extirpated specimens from 9 patients with colorectal carcinoma, fucosyltransferase activities in the carcinoma tissue and the normal mucosa were measured and were compared with the hlstochemical findings of glycoconjugates which were shown by staining with lectins reacting with blood group antigens and related substances. The fucosyltransferase activities of the carcinoma tissue were well correlated with the overall findings of lectin stainings after neuraminidase treatment. The more intense the carcinoma tissue was stained, the higher the fucosyltransferase activity was shown. However, there were marked differences in the fucosyltransferase activities by the portions measured, depending upon the relative amount of carcinoma tissue and Interstitial tissue; in the invasive portion with less carcinoma tissue, the activity was generally low in comparison with that in the surface area where carcinoma tissue was rather abundant. Thus, the morphological and lectin hlstochemical finding are of paramount importance for the eveluation of glycosyltransferase activity in human colorectal carcinoma. 相似文献