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81.
Cellular Adherence, Glucosyltransferase Adsorption, and Glucan Synthesis of Streptococcus mutans AHT Mutants 总被引:1,自引:8,他引:1 下载免费PDF全文
Streptococcus mutans AHT mutants M1, M2, and M13 failed to adhere to a glass surface, whereas mutants M9 and M35 exhibited decreased and increased adherence, respectively, as compared with the parent strain, when grown in sucrose broth. Extracellular glucosyltransferase prepared from glucose-grown cultures of the adherent strains (wild type, M9, and M35) induced adherence of heat-killed cells of the homologous and heterologous streptococcal strains as well as of Escherichia coli K-12 and uncoated resin particles. The glucosyltransferase was adsorbed on all the streptococcal cells and glucan-coated resins, but not on E. coli cells and the uncoated resins. Glucosyltransferase from the nonadhering mutants (M1, M2, M13) neither was significantly adsorbed on nor induced adherence of any of the cells and resins. Cell-free enzymes from the glucose-grown adherent strains produced water-soluble and water-insoluble glucans, whereas those from the nonadhering mutants produced only water-soluble glucans. Small amounts of alkali-soluble, cell-associated glucan were recovered from the sucrose-grown nonadhering mutants. Thus, the relative proportions of glucosyltransferase isozymes elaborated by the S. mutans mutants, insofar as they affect the physico-chemical properties of the glucans produced, seem to determine the adherence abilities of the cells. The adsorption of glucosyltransferase on glucan molecules on the cell surface is not required for the adherence of S. mutans, but de novo glucan synthesis is important in the adherence process. 相似文献
82.
S Okamoto Y Tanaka H F DeLuca Y Kobayashi N Ikekawa 《The American journal of physiology》1983,244(2):E159-E163
The biological activity of 24,24-difluoro-1,25-dihydroxyvitamin D3 was compared with 1,25-dihydroxyvitamin D3 in the rat. The 24,24-difluoro-1,25-dihydroxyvitamin D3 has a potency of approximately 5-10 times that of 1,25-dihydroxyvitamin D3 in the known in vivo vitamin D responsive systems. These systems include intestinal calcium transport, bone calcium mobilization, calcification of epiphyseal plate cartilage, and elevation of plasma calcium and phosphorus concentrations. Thus, 24,24-difluoro-1,25-dihydroxyvitamin D3 is the first known analogue with higher potency than 1,25-dihydroxyvitamin D3 in vivo. 相似文献
83.
Comparative morphology of endodermal sinus tumor (Teilum) to human yolk sac and a proposal of endodermal cell tumor 总被引:1,自引:0,他引:1
T Okamoto 《Acta pathologica japonica》1983,33(1):1-14
Histological criteria of 8 pure and typical endodermal sinus tumor (EST) were compared with the morphological features of 8 human yolk sacs from 5 to 13 weeks of pregnancy. No common features were found with regard to endodermal sinus structure (ESS) and clear-cell entoblastic pattern (CCEP), but magma reticulare (MR) and eosinophilic hyaline globules (EHG) were detected as common findings. As to the morphology and synthesis of alpha-fetoprotein (AFP), some tumor cells with eosinophilic-granular cytoplasm lining ESS had similarity to the endodermal cell of human yolk sac. Histological features of EST mimicked the morphological structure of endodermal sinus in rodent yolk sac. Pathological study on an ovarian and a gastric adenocarcinoma with high level of AFP concentration demonstrated two cell patterns with eosinophilic-granular and clear cytoplasm showing analogousness to the endodermal cell of human yolk sac. It was suggested that these tumors showed a selective differentiation to the endodermal cell of human yolk sac and might be called ECT. Further study clarified that ovarian embryonal carcinoma or teratocarcinoma with higher AFP concentration had vitelline component of EST or ECT or both. 相似文献
84.
Shigetoshi Horiguchi Yoshitaka Okamoto Shuji Yonekura Toru Okawa Naoki Kunii Heizaburo Yamamoto Daiju Sakurai Toyoyuki Hanazawa 《Arerugī》2008,57(5):558-561
BACKGROUND: Japanese cedar and cypress pollen share a common antigen. The cedar pollen season is followed by the cypress pollen season. However, both the clinical significance and involvement of cypress pollinosis in the treatment of the cedar pollinosis have not yet been clarified. METHODS: The clinical efficacy of sublingual immunotherapy with cedar pollen extract for cedar pollinosis was evaluated during the cypress pollen dispersal season in Japan. In addition, the change in cypress pollen specific IgE antibodies of the patients with cedar pollinosis was examined before and after the pollen season. RESULTS: Sublingual immunotherapy with cedar pollen extract did not improve the clinical symptoms of the cedar pollinosis patients combined with cypress pollinosis in the cypress pollen season. The cypress pollen specific IgE antibodies were found to demonstrate significant seasonal changes. CONCLUSION: The presence of cypress pollinosis should therefore be taken into consideration when planning the optimal treatment for cedar pollinosis. Sublingual immunotherapy with cedar pollen extract may not be effective for cypress pollinosis. 相似文献
85.
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
86.
H Kanagawa E Takai F Tsuda A Machida M Kojima A Ishijima T Tanaka H Okamoto Y Miyakawa M Mayumi 《Journal of medical virology》1992,37(4):288-293
Of sera from 1,878 Japanese blood donors who carried hepatitis B surface antigen (HBsAg), 420 were subtyped as adw (22.4%) and 1,443 as adr (76.8%); only 15 (0.8%) contained HBsAg of subtype ayw or ayr. Sera with HBsAg/adr had higher HBsAg titres than those with HBsAg/adw (geometric mean of haemagglutination titre: 10.1 +/- 2.4 vs. 9.7 +/- 2.4, p less than 0.01), and a higher prevalence of hepatitis B e antigen (24% vs. 13%, p less than 0.001). Carriers of HBsAg/adr progressively predominated over those of HBsAg/adw with increasing age. Of sera from 1,863 carriers of HBsAg/adw or HBsAg/adr, 182 (9.8%) contained HBsAg particles with both subtypic determinants in the w/r allele. The presence of w and r determinants on the same particles was ascertained by sandwiching them between monoclonal antibody with the specificity for w and that with the specificity for r. HBsAg particles of compound subtype (adwr) were found more often in sera with hepatitis B e antigen than those without it (145/403 [36.0%] vs. 37/1,460 [2.5%], p less than 0.001). Sera with HBsAg/adwr particles had HBsAg titres higher than those without them (12.4 +/- 1.9 vs. 9.7 +/- 2.3, p less than 0.001). HBsAg/adwr particles arise from phenotypic mixing of the S-gene product of wild-type virus and that of mutants with point mutations for subtypic changes. The results obtained indicated that HBV strains of subtype adr have a higher replicative activity than those of adw, and suggested that mutations in the S gene for subtypic changes would be associated with an active replication of hepatitis B virus. 相似文献
87.
The distribution of [Met]enkephalin-Arg6-Gly7-Leu8 (MEAGL)-immunoreactive (-IR) neurons and its modification after enucleation have been investigated in the rat superior colliculus. In normal rats and on the ipsilateral side of monocular-enucleated rats, small sized vertically elongated fusiform-shaped weakly immunostained neurons were dispersed throughout the sublamina of the stratum griseum superficiale (SGS). In bilaterally enucleated rats and on the contralateral side of monocular-enucleated rats, many small strongly immunoreactive MEAGL-containing neurons, projecting processes horizontally or obliquely toward the surface, appeared in the deepest part of the SGS and the superficial part of the stratum opticum (SO), in contrast to the disappearance of the fusiform-shaped weakly stained neurons in the SGS. MEAGL-IR fibers increased in density throughout the sublamina of the SGS, being densest in the deep SGS, accompanying their increase in the neighboring SO. Sporadically found MEAGL-IR neurons in the deep SO and the stratum griseum intermediale did not show the detectable change of immunoreactivity. These results indicate that enkephalin biosynthesis is undergone by different type of neurons in the normal and the ocular-derived superior colliculus, and suggest that some neurons in the adult superior colliculus have a potentiality to express the peptidergic phenotype. 相似文献
88.
A human vitelline component in embryonal carcinoma of the testis 总被引:1,自引:0,他引:1
T Okamoto 《Acta pathologica japonica》1986,36(1):41-48
The correlation between increased serum alpha-fetoprotein (AFP) and a human vitelline component of 5 testicular embryonal carcinomas (1 was one histological type, 4 were more than one histological type) with no histological features specific for yolk sac tumor (YST) or endodermal sinus tumor (EST) was presented. In all 5 cases, distinct cells simulating the human yolk sac endodermal cell (HYSEC) with eosinophilic-granular or clear-vacuolated cytoplasm were found. These cells contained PAS positive, diastase resistant eosinophilic hyaline globules (EHG) which were positive for AFP. In the embryoid body, the same cells with positive AFP as the HYSEC were also seen. Electron microscopic investigation of these cells revealed basement membrane-like materials which were observed in organoid structure of YST. Positive AFP in these cells showed no binding to Concanavalin A (Con A), which was similar to AFP in YST. It was suggested that testicular embryonal carcinoma with higher serum AFP showing no histological features specific for YST had a vitelline component simulating the HYSEC and produced an increased serum AFP. Immunohistochemical staining for AFP of embryonal carcinoma with higher serum AFP is useful for detecting a human vitelline component and is important to guess the survival for the patient. 相似文献
89.
Sugita Y Takahashi Y Hayashi I Morimatsu M Okamoto K Shigemori M 《Pathology international》1999,49(12):1114-1118
A pineal tumour in a 27-year-old male is presented with the characteristic histological features of a pineal malignant rhabdoid tumor (MRT) with chondroid formation. Occasionally, tumor cells contained a single well-demarcated hyaline globular inclusion within the cytoplasm adjacent to the nucleus. The stroma of these tumors tends to be densely hyalinized and become chondroid. Immunohistochemical staining was positive for vimentin, epithelial membrane antigen, chromogranin A, synaptophysin, neuron-specific enolase, S-100 protein, and muscle actin. Despite surgery and radiochemotherapy, the tumor recurred in the pineal region and metastasized to the lower lobe of right lung. The patient died 2 years after the initial diagnosis. This is the second published case of central nervous system-MRT appearing in an adult. The clinical and pathological features of pineal MRT in this patient are presented. 相似文献
90.
Tsukasa Okamoto 《Pathology international》1986,36(1):41-48
The correlation between increased serum alpha-fetoprotein (AFP) and a human vitelline component of 5 testicular embryonal carcinomas (1 was one histological type, 4 were more than one histological type) with no histological features specific for yolk sac tumor (YST) or endodermal sinus tumor (EST) was presented. In all 5 cases, distinct cells simulating the human yolk sac endodermal cell (HYSEC) with eosinophilic-granular or clear-vacuolated cytoplasm were found. These cells contained PAS positive, diastase resistant eosinophilic hyaline globules (EHG) which were positive for AFP. In the embryoid body, the same cells with positive AFP as the HYSEC were also seen. Electron microscopic investigation of these cells revealed basement membrane-like materials which were observed in organoid structure of YST. Positive AFP in these cells showed no binding to Concanavalin A (Con A), which was similar to AFP in YST. It was suggested that testicular embryonal carcinoma with higher serum AFP showing no histological features specific for YST had a vitelline component simulating the HYSEC and produced an increased serum AFP. Immunohistochemical staining for AFP of embryonal carcinoma with higher serum AFP is useful for detecting a human vitelline component and is important to guess the survival for the patient. 相似文献