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61.
The study of the reaction of some methylenebisphenols with chloranil in ethanol and also of a phenol formaldehyde condensate prepared by acid catalysis, reveals that quinone methide is formed in the self-cure of quinoid phenol formaldehyde resin. The quinone methide reacts with ethanol to give an adduct. The structure of the alcohol adduct is identified by NMR and IR data and by means of pyrolysis. 相似文献
62.
The full expression of the ity phenotype in ityr mice requires C3 activation by Salmonella lipopolysaccharide.
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Our previous study has shown that the rapid and sufficient activation of complement by Salmonella lipopolysaccharide occurs in genetically resistant (Ityr) A/J mice. To assess whether the level of complement activation by a virulent strain of Salmonella typhimurium regulates the level of murine natural resistance, we compared levels of serum complement activation by S. typhimurium and kinetics of serum-opsonized S. typhimurium grown in macrophages using several strains of resistant (Ityr) and susceptible (Itys) mice. Itys macrophages killed intracellular S. typhimurium to the same extent as did Ityr macrophages when the pathogen was opsonized with Ityr serum. Opsonization of S. typhimurium with Itys serum reduced intracellular killing activity in Ityr macrophages to the same level as seen with Itys macrophages. Incubation of S. typhimurium with 25% Mg2+ EGTA (5 mm MgCl2-3 mm ethylene glycol-bis (beta-aminotheyl either)-N,N,N',N'-tetraacetic acid)-chelated Ityr serum resulted in higher levels of C3 deposition onto the surface of this bacteria, C3b generation and also C3 consumption, compared with that with Mg2+ EGTA-chelated Itys serum. Opsonization of S. typhimurium with A/J serum prior to infection increased early resistance in Itys mice. Infection with a virulent strain of S. typhimurium induced the expression of interleukin-10 (IL-10) mRNA at higher levels in C57BL/6 mice than in A/J mice. However, opsonization of S. typhimurium with A/J serum decreased bacterial growth in the spleen of C57BL/6 mice to the same level as observed for A/J mice in association with decreased expression levels of IL-10 mRNA. Moreover, administration of anti-C3 antibodies reduced the resistance of A/J mice in association with a decrease in serum levels of C3. These results indicate that the high level of complement activation via the alternative pathway in Ityr serum by a virulent strain of S. typhimurium reduces the virulence of this pathogen, which may contribute to the full expression of Ity phenotype in Ityr mice. 相似文献
63.
Developmental switch from GABA to glycine release in single central synaptic terminals 总被引:8,自引:0,他引:8
Nabekura J Katsurabayashi S Kakazu Y Shibata S Matsubara A Jinno S Mizoguchi Y Sasaki A Ishibashi H 《Nature neuroscience》2004,7(1):17-23
Early in postnatal development, inhibitory inputs to rat lateral superior olive (LSO) neurons change from releasing predominantly GABA to releasing predominantly glycine into the synapse. Here we show that spontaneous miniature inhibitory postsynaptic currents (mIPSCs) also change from GABAergic to glycinergic over the first two postnatal weeks. Many 'mixed' mIPSCs, resulting from co-release of glycine and GABA from the same vesicles, are seen during this transition. Immunohistochemistry showed that a large number of terminals contained both GABA and glycine at postnatal day 8 (P8). By P14, both the content of GABA in these mixed terminals and the contribution of GABA to the mixed mIPSCs had decreased. The content of glycine in terminals increased over the same period. Our results indicate that switching from GABAergic to glycinergic inputs to the LSO may occur at the level of a single presynaptic terminal. This demonstrates a new form of developmental plasticity at the level of a single central synapse. 相似文献
64.
65.
C-reactive protein levels in the serum of asthmatic patients. 总被引:1,自引:0,他引:1
Miyoshi Fujita Shigeharu Ueki Wataru Ito Takahito Chiba Masahide Takeda Norihiro Saito Hiroyuki Kayaba Junichi Chihara 《Annals of allergy, asthma & immunology》2007,99(1):48-53
BACKGROUND: Asthma is a chronic airway inflammatory disease caused by immune cells such as T lymphocytes and eosinophils. Recently, highly sensitive C-reactive protein (hs-CRP) assays have become available for detecting small changes in CRP levels within the reference range, allowing for the evaluation of clinical inflammation. OBJECTIVE: To investigate the relationship between hs-CRP levels and bronchial asthma. METHODS: We collected blood samples from 109 patients with bronchial asthma, with or without attacks, and measured serum eosinophil cationic protein levels, pulmonary function, and serum CRP levels using an hs-CRP assay. RESULTS: Mean serum hs-CRP levels were significantly higher in patients without attacks (0.473 mg/L) and with attacks (0.908 mg/L) (P < .001 for both) than in controls (0.262 mg/L). Serum hs-CRP levels were inversely correlated with forced expiratory volume in 1 second/forced vital capacity in asthmatic patients (r = -0.4915; P < .01). CONCLUSION: Serum hs-CRP levels may be related to the state of asthma exacerbation and allergic inflammation. 相似文献
66.
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
67.
Otsuka Y Ito M Yamaguchi M Saito S Uesu K Kasai K Abiko Y Mega J 《Mechanisms of ageing and development》2002,123(6):663-674
It is well known that Down syndrome (DS) is a premature ageing syndrome. Periodontal disease in individuals with DS develops rapidly and extensively in a relatively younger age bracket compared with that in healthy controls. The mechanisms involved in the periodontal inflammatory processes in DS patients are not fully understood. In the present study, the non-inflamed gingival fibroblasts isolated from seven patients with DS (DGF) and seven healthy controls (NDGF) were stimulated with lipopolysaccharide (LPS) derived from Actinobacillus actinomycetemcomitans (A. a.). We measured the level of prostaglandin E2 (PGE2) production by DGF and NDGF by radioimmunoassay, and also measured the mRNA expression of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) by using the real-time PCR method. We found the higher levels of LPS-stimulated COX-2 mRNA expression and PGE2 production in DGF when compared with those in NDGF. This study may indicate that overexpression of LPS-stimulated COX-2 induced a greater ability of DGF to produce PGE2, and that these phenomena may be responsible for the severer periodontal disease in DS patients. 相似文献
68.
Adherence of Pasteurella multocida or Bordetella bronchiseptica to the swine nasal epithelial cell in vitro. 总被引:4,自引:3,他引:4
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The interaction of Bordetella bronchiseptica or Pasteurella multocida with swine nasal epithelial cells was studied in vitro. The mean number of B. bronchiseptica organisms adhered per cell was about three times as high as that of P. multocida (P less than 0.01), and the adherence was specifically inhibited by the homologous antiserum prepared with the whole-cell antigen of each bacterium. The poor affinity of P. multocida to the swine nasal mucosa as compared with that of B. bronchiseptica was also demonstrated in the cultured fragments of the nasal mucosa. When observed with a scanning electron microscope, B. bronchiseptica organisms colonized the fragments, whereas few P. multocida organisms adhered. Morphologically, the P. multocida-infected fragments had an essentially normal structure, whereas marked degeneration and marked desquamation of the epithelial cells and severe inflammatory reactions were observed in many areas of the B. bronchiseptica-infected fragments. These morphological observations were consistent with those for the nasal mucosa of P. multocida- or B. bronchiseptica-infected neonatal pigs (T. Nakai, K. Kume, H. Yoshikawa, T. Oyamada, and T. Yoshikawa, Jpn. J. Vet. Sci. 48:693-701, 1986; T. Oyamada, T. Yoshikawa, H. Yoshikawa, M. Shimizu, T. Nakai, and K. Kume, Jpn. J. Vet. Sci. 48:377-387, 1986). Cultured swine nasal fragments, however, were equally injured when they were incubated in a medium containing purified dermonecrotic toxin (DNT) preparations of B. bronchiseptica or P. multocida. Therefore, these DNT preparations can induce morphological damage closely resembling that induced in vivo. Hence, colonization of B. bronchiseptica and production of its DNT on the swine nasal mucosa appear to result in the production of mucosal damage. On the other hand, P. multocida seems to lack the ability to colonize normal swine nasal mucosa, thus resulting in no production or the slight production of DNT to such an extent as to produce mucosal damage. The present data support our previous hypothesis (Nakai et al.; Oyamada et al.) that B. bronchiseptica induces swine atrophic rhinitis, whereas P. multocida does not. 相似文献
69.
Junichi Tamaru Atsuo Mikata Makiko Itami Toshiyuki Takagi 《Pathology international》1990,40(7):517-521
Human non-Hodgkin's lymphomas were studied by means of an avidin biotin complex immunoperoxidase method using several monoclonal antibodies against the intermediate filament protein, vimentin. The study cases were 61 B cell lymphomas (including 2 plasmacytomas) and 30 T cell lymphomas (including 8 cases of mycosis fungoides). Twelve of the 61 B cell lymphomas were positive for vimentin, and were composed of extrafollicular center cells such as immunoblastic and plasmacytoid cells. On the other hand, lymphomas of follicular center cell origin were negative for vimentin. All cases of T cell lymphoma except for 14 (all of 9 AlLD- type lymphomas, all of 4 lymphoblastic lymphomas and one diffuse mixed small/ large lymphoma) were positive for vimentin. Although vimentin expression appeared to be influenced by various conditions such as the proportion of T- and B cell subsets, or B cell proliferation rate, follicular center cells were constantly negative for vimentin. 相似文献
70.
Takanori Hirose Toshiaki Sano Junichi Abe Kazuo Hizawa Shigeki Hatakeyama Itsumi Mori 《Ultrastructural pathology》1988,12(5):529-536
A case of recurrent soft part sarcoma with focal areas showing epithelial differentiation in the right thigh in a 78-year-old woman is reported. The primary tumor consisted of myxoid areas and solid areas, in which relatively uniform epithelioid tumor cells were arranged in sheets, whereas pleomor-phism and a storiform pattern appeared in the recurrent tumors. Thus this tumor was suspected to be a malignant fibrous histiocytoma. However, further studies showed unexpected ultrastructural and immunohistochemical features. Cytokeratin immu-noreactivity and tonofilamentlike structures probably indicated epithelial differentiation of some tumor cells. From the clinical and histological findings, this tumor should be identified as a malignant fibrous histiocytoma with phenotypic expressions of epithelial cell. 相似文献