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41.
Tadaaki Yokota Tokuhiro Ishihara Hiroo Kawano Mutsuo Takahashi Yoshimi Yamashita Toshikazu Gondo Yoshihiro Fujinaga Fumiya Uchino 《Pathology international》1989,39(6):349-355
Amyloid enhancing factor (AEF) was extracted from spleens of mice that had received amyloidogenic stimulation. Sephacryl S 300 gel filtration of the crude AEF yielded five fractions, among which strong AEF activity was present in the first peak (Fl), and confirmed by an amyloid induction experiment. An anti AEF antiserum was obtained from a rabbit by immunization with Fl. This antibody reacted strongly with splenic polymorphonuclear leukocytes (PML) from mice given amyloidogenic stimulation, and weakly with those from normal untreated mice. Isoelectric focusing (IEF) analysis of both Fl and sera from mice given amyloidogenic stimulation was performed. A single band was observed on IEF analysis of Fl, whereas many bands were seen on IEF analysis of the sera. After the substances in the gel had been transferred to nitrocellulose membranes by capillary blotting, the membranes were made to react with the anti-AEF antiserum. The results suggested that AEF is a high molecular-weight substance derived from PML and increases in the serum at the time of, or shortly prior to, amyloid deposition in the spleen. Acta Pathol Jpn 39: 349∼355, 1989. 相似文献
42.
Namiki T Yanagawa S Izumo T Ishikawa M Tachibana M Kawakami Y Yokozeki H Nishioka K Kaneko Y 《Cancer Genetics and Cytogenetics》2005,157(1):1-11
To clarify the correlation of genomic alterations with clinical and histological features, we performed metaphase comparative genomic hybridization analysis on 20 primary cutaneous melanomas, which were obtained by laser capture or manual microdissection, and 16 melanoma cell lines. There were no differences in the average number of aberrations between acral melanomas (AM) and non-AM, although gains of 5q and 11q13 were more frequent (P=0.05) and 10q loss was less frequent (P=0.01) in AM than in non-AM. Although tumor thickness is considered a measurable estimate of clinical expression, there were no differences in the average number of aberrations among 4 groups, classified by thickness of the tumor. While the majority of aberrations were equally distributed among the 4 groups, 6p gains were found only in the thickest tumors. Patients with 6p or 1q gains had a lower overall survival rate than those without them (P=0.0002 or P=0.013). While gains of 1q, 2q, 3p, 3q, 7q, 20p, and 20q were more frequent in the cell lines than in the primary tumors (P<0.01), losses of 6q, 9p, 10p, and 10q were equally found in both cell lines and primary tumors. The present study showed that chromosomal aberrations had already occurred in the thinner tumors, and that 6p and 1q gains may be a prognostic factor. 相似文献
43.
Two distinct antigenic types of the polysaccharide chains of Helicobacter pylori lipopolysaccharides characterized by reactivity with sera from humans with natural infection 下载免费PDF全文
Yokota SI Amano KI Shibata Y Nakajima M Suzuki M Hayashi S Fujii N Yokochi T 《Infection and immunity》2000,68(1):151-159
We have purified lipopolysaccharides (LPS) from 10 Helicobacter pylori clinical isolates which were selected on the basis of chemotype and antigenic variation. Data from immunoblotting of the purified LPS with sera from humans with H. pylori infection and from absorption of the sera with LPS indicated the presence of two distinct epitopes, termed the highly antigenic and the weakly antigenic epitopes, on the polysaccharide chains. Among 68 H. pylori clinical isolates, all smooth strains possessed either epitope; the epitopes were each carried by about 50% of the smooth strains. Thus, H. pylori strains can be classified into three types on the basis of their antigenicity in humans: those with smooth LPS carrying the highly antigenic epitope, those with smooth LPS carrying the weakly antigenic epitope, and those with rough LPS. Sera from humans with H. pylori infection could be grouped into three categories: those containing immunoglobulin G (IgG) antibodies against the highly antigenic epitope, those containing IgG against the weakly antigenic epitope, and those containing both specific IgGs; these groups made up about 50%, less than 10%, and about 40%, respectively, of all infected sera tested. In other words, IgG against the highly antigenic epitope were detected in more than 90% of H. pylori-infected individuals with high titers. IgG against the weakly antigenic epitope were detected in about 50% of the sera tested; however, the antibody titers were low. The two human epitopes existed independently from the mimic structures of Lewis antigens, which are known to be an important epitope of H. pylori LPS. No significant relationship between the reactivities toward purified LPS of human sera and a panel of anti-Lewis antigen antibodies was found. Moreover, the reactivities of the anti-Lewis antigen antibodies, but not human sera, were sensitive to particular alpha-L-fucosidases. The human epitopes appeared to be located on O-polysaccharide chains containing endo-beta-galactosidase-sensitive galactose residues as the backbone. Data from chemical analyses indicated that all LPS commonly contained galactose, glucosamine, glucose, and fucose (except one rough strain) as probable polysaccharide components, together with typical components of inner core and lipid A. We were not able to distinguish between the differences of antigenicity in humans by on the basis of the chemical composition of the LPS. 相似文献
44.
K Amano N Suzuki H Hatakeyama Y Kasahara S Fujii K Fukushi T Suto F Mahara 《Acta virologica》1992,36(1):67-72
Of the sera which were positive to Rickettsia tsutsugamushi by indirect immunoperoxidase test, approximately 80% sera were positive to a Proteus OXK antigen by Weil-Felix test at 10 or more days after the onset of fever, while only 10% sera were positive within 9 days from the onset of fever. In ELISA using the OXK antigen, almost all of the paired sera of tsutsugamushi disease (TD) patients increased on the IgM antibody titres with the rise of their titres by Weil-Felix test, whereas the IgG antibody titres of these sera were unrelated with the titres of Weil-Felix test. We suspect that the reactivity of TD patients sera to the OXK antigen in Weil-Felix test was derived from the reactivity of the IgM antibody against the OXK antigen common with R. tsutsugamushi. The patient sera infected with a Japanese isolate of spotted fever group rickettsia (SFGR) cross-reacted with the Thai Tick Typhus (TTT) strain of SFGR by indirect immunoperoxidase test. In Weil-Felix test, the reactivity of these sera to OX2 antigen were higher than that to OX19 antigen, like the sera infected with other SFGR, except of R. rickettsii. These sera also reacted with TTT and OX2 antigens by ELISA. The titres of IgM antibody against OX2 antigen in the sera in ELISA were in parallel with the titres of the sera against OX2 antigen in Weil-Felix test, but not the titres of IgG antibody. We suggest that the reactivity of the patient sera infected with SFGR to OX2 antigen of Weil-Felix test is dependent on the IgM antibody. 相似文献
45.
Chemical properties of lipopolysaccharides from spotted fever group rickettsiae and their common antigenicity with lipopolysaccharides from Proteus species. 总被引:2,自引:2,他引:2 下载免费PDF全文
The lipopolysaccharides (LPS) isolated from spotted fever group (SFG) rickettsia strains Thai tick typhus TT-118 and Katayama were characterized by chemical analyses, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, enzyme-linked immunosorbent assay (ELISA), and immunoblotting. These LPS did not contain heptose, but they contained 3-deoxy-D-manno-octulosonic acid (KDO), glucosamine, quinovosamine, phosphate, ribose, an unknown neutral sugar, and palmitic acid. Resolution of the apparent molecular masses of these LPS by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and staining with silver showed ladder-like bands. In an ELISA, convalescent-phase sera from 10 patients with Japanese spotted fever reacted with LPS from the Katayama strain, and 90% (9 of 10) of these sera also reacted with LPS isolated from Proteus vulgaris OX2. Immunoblotting revealed that the sera reacted with the high-molecular-mass bands of LPS from SFG rickettsiae, in addition to those of OX2 LPS. In an ELISA, immunoglobulin M antibodies from these sera reacted with the O-polysaccharide and lipid A portions of LPS from P. vulgaris OX2. The epitopes common to LPS of SFG rickettsiae and P. vulgaris OX2 may be in the O-polysaccharide and lipid A portions. 相似文献
46.
Immunological unresponsiveness in mice. II. Cellular basis of immunological unresponsiveness induced in foetal and neonatal mice by transfer of human gamma-globulin by the maternal route. 下载免费PDF全文
The cellular basis of the mechanism of immunological tolerance to human gamma-globulin (H gamma G) induced in foetal and neonatal mice by materno-foetal or materno-neonatal transfer after a single injection of tolerogen (deaggregated H gamma G) into the mothers was investigated using a cell transfer system and assays of passive haemagglutinating antibodies and plaque-forming cells to H gamma G. The results demonstrated that B cells are mainly involved in the tolerance induced on the fourteenth day of gestation, whereas inactivation of T cells may account for the tolerance induced on the eighteenth day of gestation and in the neonatal stage. Treatment of the mothers with tolerogen and then anti-H gamma G serum reduced the tolerance induced on the fourteenth day of gestation, but did not affect that induced on the eighteenth day of gestation and in the neonatal stage. Cell transfer experiments showed that B-cell tolerance induced on the fourteenth day of gestation was prevented by passive antibody, while T-cell tolerance induced on the eighteenth day of gestation and in the neonatal stage was not affected by passive antibody. Assay of the anti-DNP antibody response after immunization with DNP10-H gamma G showed that treatment of mice with the tolerogen on the eighteenth day of gestation, but not the fourteenth day of gestation, inactivated H gamma G-reactive helper cells. The significance of these results is discussed in relation to the results of the cell transfer experiments described as above. 相似文献
47.
Murine macrophage interleukin-1 release by capsularlike serotype-specific polysaccharide antigens of Actinobacillus actinomycetemcomitans. 总被引:2,自引:6,他引:2 下载免费PDF全文
T Takahashi T Nishihara Y Ishihara K Amano N Shibuya I Moro T Koga 《Infection and immunity》1991,59(1):18-23
Serotype-specific polysaccharide antigens (SPAs) were extracted from whole cells of Actinobacillus actinomycetemcomitans ATCC 29523 (serotype a), Y4 (serotype b), and NCTC 9710 (serotype c) by autoclaving and purified by chromatography on DEAE-Sephadex A-25 and Sephacryl S-300 columns. Y4 SPA induced interleukin-1 (IL-1) release by P388D1 murine macrophages. Polymyxin B had virtually no effect on the release of IL-1. Rabbit anti-murine IL-1 serum strongly suppressed the proliferation of C3H/HeJ mouse thymocytes induced with the culture supernatants of Y4 SPA-stimulated P388D1 cells and a submitogenic dose of concanavalin A. Gel filtration of the culture supernatants of Y4 SPA-stimulated macrophages on Sephacryl S-200 showed that an IL-1 peak at a point corresponding to approximately 16.5 kDa was eluted. The ability of SPAs from strains ATCC 29523 and NCTC 9710 to induce the release of IL-1 was lower than that of Y4 SPA. The IL-1-releasing ability of serotype a and c antigens was enhanced by deacetylation of both polysaccharides, suggesting that acetyl groups of these antigens might hinder the interaction between the antigens and macrophages. 相似文献
48.
Distribution of Porphyromonas gingivalis strains with fimA genotypes in periodontitis patients 总被引:11,自引:0,他引:11 下载免费PDF全文
Amano A Nakagawa I Kataoka K Morisaki I Hamada S 《Journal of clinical microbiology》1999,37(5):1426-1430
Fimbriae (FimA) of Porphyromonas gingivalis are filamentous components on the cell surface and are thought to play an important role in the colonization and invasion of periodontal tissues. We previously demonstrated that fimA can be classified into four variants (types I to IV) on the basis of the nucleotide sequences of the fimA gene. In the present study, we attempted to detect the four different fimA genes in saliva and plaque samples isolated from patients with periodontitis using the PCR method. Four sets of fimA type-specific primers were designed for the PCR assay. These primers selectively amplified 392-bp (type I), 257-bp (type II), 247-bp (type III), and 251-bp (type IV) DNA fragments of the fimA gene. Positive PCR results were observed with reference strains of P. gingivalis in a type-specific manner. All other laboratory strains of oral and nonoral bacteria gave negative results. The sensitivity of the PCR assay for fimA type-specific detection was between 5 and 50 cells of P. gingivalis. Clinical samples were obtained from saliva and subgingival plaque from deep pockets (>/=4 mm) of 93 patients with periodontitis. Bacterial genomic DNA was isolated from the samples, and the targeted fragments were amplified by PCR. The presence of P. gingivalis was demonstrated in 73 patients (78.5%), and a single fimA gene was detected in most patients. The distribution of the four fimA types among the P. gingivalis-positive patients was as follows: type I, 5.4%; type II, 58.9%; type III, 6. 8%; type IV, 12.3%; types I and II, 6.8%; types II and IV, 2.7%; and untypeable, 6.8%. P. gingivalis with type II fimA was detected more frequently in the deeper pockets, and a significant difference of the occurrence was observed between shallow (4 mm) and deep (>/=8 mm) pockets. These results suggest that P. gingivalis strains that possess type II fimA are significantly more predominant in periodontitis patients, and we speculate that these organisms are involved in the destructive progression of periodontal diseases. 相似文献
49.
Immunochemical and structural characterization of a serotype-specific polysaccharide antigen from Actinobacillus actinomycetemcomitans Y4 (serotype b). 总被引:1,自引:9,他引:1 下载免费PDF全文
A serotype-specific polysaccharide antigen of Actinobacillus actinomycetemcomitans Y4 (serotype b) was extracted from whole cells by autoclaving. The extract was purified by chromatography on DEAE-Sephadex A-25 and Sephacryl S-300 columns. The purified polysaccharide antigen formed a single precipitin line with anti-type b serum but not with anti-type a serum and anti-type c serum. The antigen was composed of 43.9% L-rhamnose, 49.1% D-fucose, and a trace amount of fatty acid. Methylation analysis, Smith degradation, and optical rotation data showed that the antigen was a polymer consisting of a disaccharide repeating unit, ----3)-alpha-D-fucopyranosyl-(1----2)-beta-L-rhamnopyranosyl-(1----. In quantitative precipitin inhibition tests, D-fucose and L-rhamnose showed very low inhibition, but the partial hydrolysate of the purified antigen was an effective inhibitor, suggesting that the serotype b specific antiserum recognizes the larger oligosaccharide units. 相似文献
50.
Syun Hosoda Hiroo Tateno Hanae Kito Inoue Genzo Isojima Sadahiko Kondo Takayoshi Konishi 《Pathology international》1992,42(8):614-620
A 69-year old man complaining of longstanding hearing loss and mild otorrhea was found to have a mass obliterating the external auditory canal and polypous tympanic mucosa with accompanying absence of the tympanic membrane and ossicular chain. Tumors excised from the external auditory canal and tympanum showed histologic features essentially characteristic of a carcinoid tumor: a ribbon or festoon arrangement of tumor cells, formation of anastomosing cords and glandular spaces, presence of numerous argyrophilic as well as argentaffin secretory granules within many of the tumor cells, and ultrastructur-al evidence of neurosecretory granules in the tumor cell cytoplasm. Immunohistochemically, the tumor was found to contain not only neuronal marker substances such as neuron-specific enolase, S 100 protein and chromogranin A, but also serotonin and multiple peptide hormones such as pancreatic polypeptide, glucagon, cholecystokinin and leucine-enkephalin. A review of the pathology of 17 previous cases of carcinoid of the middle ear suggested that this type of carcinoid may have a variegated hormone profile among carcinoids of foregut origin, and hormonally may resemble ileal carcinoid arising from the midgut, although their histogenetic origins may differ, because of frequent production of serotonin. Acta Pathol Jpn 42: 614–620, 1992. 相似文献