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81.
CD10 is a cell surface metalloprotease expressed by a variety of normal cell types, including lymphoid precursor cells, germinal center B lymphocytes, and some epithelial cells. We noticed that stromal cells of some cancers are positive for CD10. In this study, we investigated the role of CD10 produced by the stromal cells of colorectal neoplasms in the progression of colorectal neoplasms. Immunohistochemical examination of CD10 and p53 was performed in 169 colorectal epithelial neoplasms representing various stages of carcinogenesis. The results were correlated with the morphologic characteristics of the neoplasms. There was no expression of CD10 in the stromal cells of normal colorectal tissue. CD10-positive stromal cells were present adjacent to the tumor cells in 16 of 73 adenomas with mild or moderate dysplasia. More frequent expression of CD10 by the stromal cells was detected in adenomas with severe dysplasia (12 of 17), intramucosal carcinomas (10 of 16), and invasive carcinomas (50 of 63) than in adenomas with mild or moderate dysplasia (P < 0.0001). Expression of CD10 by > 10% of the stromal cells was detected only within the area of the invasive growth front of invasive carcinomas, not in adenomas and in only 1 of the intramucosal carcinomas. The difference between invasive and non invasive tumors was significant (P < 0.0001). The stromal expression of CD10 was significantly associated with the accumulation of p53 and a larger tumor size. These results indicate that CD10 expression is an integral part of colorectal carcinogenesis. CD10 expression seems to contribute to the invasion and thus probably facilitates metastasis. 相似文献
82.
H Tsuda Y Shimosato M P Upton J Yokota M Terada M Ohira T Sugimura S Hirohashi 《Laboratory investigation; a journal of technical methods and pathology》1988,59(3):321-327
DNA was extracted from formalin-fixed and paraffin-embedded tissues of 85 patients with pediatric malignant solid tumors which had been resected at surgery or obtained at autopsy during a 24-year period. The tumors examined included 25 rhabdomyosarcomas, 12 Wilms' tumors, 10 hepatoblastomas and 37 neuroblastoma group tumors. Neuroblastoma group tumors were subclassified into 25 neuroblastomas and 12 ganglioneuroblastomas among which 6 composite ganglioneuroblastomas were included. Sample blocks were selected from both tumors and normal tissues in the majority of cases. We were able to reliably detect N- and c-myc gene amplification in tumor DNA by dot blot-hybridization. The N-myc gene showed approximately from 3- to 500-fold amplification in 19 of 33 cases of stage IV neuroblastoma group tumor. All of these 33 patients had been intensively treated with chemotherapy and/or radiotherapy. The c-myc was amplified 8-fold in 1 case of rhabdomyosarcoma, but neither N-myc nor c-myc was amplified in any cases of Wilms' tumor or hepatoblastoma. We retrospectively examined the association among N-myc gene amplification, prognosis, and histologic subtype in 33 patients with stage IV neuroblastoma group tumors. The survival of the patients with N-myc gene amplification was shorter than that of the patients without amplification of N-myc (p less than 0.05). There was no significant difference in prognosis between the 2 histologic subtypes; neuroblastoma and ganglioneuroblastoma, and the cases of tumors with amplified N-myc showed shorter survivals for each subtype (p less than 0.05). In every case of neuroblastoma group tumor, the copy number of the N-myc gene was the same among primary site and multiple metastatic tumors, even when the lesions showed differences in histologic subtype like neuroblastoma and ganglioneuroblastoma. 相似文献
83.
Alcoholic liver disease has been shown to progress even after cessation of ethanol intake and the involvement of an immunological mechanism has been suggested. To study whether lymphocyte cytotoxicity for autologous human hepatocytes is involved in the pathogenic process of alcoholic liver disease, hepatocytes (target cells) obtained by a needle liver biopsy from 36 patients with alcoholic liver disease were isolated by enzymatic digestion and incubated with autologous peripheral lymphocytes (effector cells). Using a microcytotoxicity assay, a cytotoxic effect was observed in patients with active cirrhosis or alcoholic hepatitis, but not in those with inactive cirrhosis, hepatic fibrosis or fatty liver. When lymphocytes were separated into T cell enriched and non-T cell enriched fractions, this cytotoxic effect was significantly greater with the non-T cell enriched lymphocyte fraction than with the T cell enriched fraction. The addition of aggregated IgG reduced the cytotoxic effect of the lymphocytes. These results suggested that antibody-dependent cell-mediated cytotoxicity may be of pathogenic importance in alcoholic liver disease. 相似文献
84.
Nobuo Tsuda Paritosh Roy Chowdhury Tomayoshi Hayashi Masanobu Anami Masachika Iseki Shigehiko Koga Fukuzo Matsuya Hiroshi Kanetake Yutaka Saito Yoshio Horita 《Pathology international》1997,47(11):778-783
Primary renal angiosarcoma is very rare. To our knowledge, only 15 cases have been reported to date. A 77-year-old Japanese man with a unilateral kidney presented with massive hematuria followed by renal failure. A renal tumor was suspected and a left nephrectomy was performed. The histopathological diagnosis was angiosarcoma of the kidney. A hemorrhagic tumor measuring 10 × 5 cm and clotted blood was found in the modularly area. The atypical tumor cells had a sinusoidal and solid appearance, and showed Immunohistochemically positive reactions for some of the endothelial markers. The patient died about 21 months after the nephrectomy and the autopsy revealed massive metastases to the liver and retroperitoneum. One of the differential diagnoses of the case was anglomyolipoma, because the tumor cells were relatively bland in their histological appearance with entrapped fat cells in the pelvic area. Fifteen case reports with titles that included the term 'hemangiosarcoma/anglosarcoma', 'hemangioendothelloma/endothelloma' or 'vascular sarcoma' of the kidney were reviewed and compared to the present case. 相似文献
85.
Relationship between phagocytosis and immunoglobulin A release from human colostral macrophages.
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Macrophages and neutrophils that contain mainly secretory immunoglobulin A (IgA) comprise the majority of cells in human colostrum. These cell populations were separated and analyzed for their ability to release total IgA and secretory IgA when stimulated to phagocytose. Colostral macrophages phagocytosed opsonized bacteria and nonopsonized latex particles; at the same time, IgA was released. Neutrophils poorly phagocytosed opsonized bacteria but actively phagocytosed latex particles. In contrast to the macrophages, the neutrophils did not release IgA, even after active phagocytosis of latex. Consequently, colostral macrophages are the main source of IgA released from colostral leukocytes when these cells are exposed to organisms or particles that are phagocytosed. A function for colostral neutrophils which sequester IgA is proposed. 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.
Takashi Hirano Shinichi Ohashi Satoshi Morimoto Keishiro Tsuda Tomowo Kobayashi Shigeru Tsukagoshi 《Macromolecular chemistry and physics.》1986,187(12):2815-2824
Polymeric conjugates of adriamycin (ADR) ( 2 ) or daunomycin (DM) ( 3 ) were synthesized by reaction of the drugs with the copolymer of divinyl ether and maleic anyhdride (DIVEMA) ( 1 ). The content of ADR moieties in the DIVEMA conjugate ( 4 ) could be varied depending on the reaction conditions up to 35,8 wt.-%. Considering the low toxicity and the high possibility of renal excretion, DIVEMA with M?w of 7000 and M?w/M?n = 1,6 was used for the conjugation. The rate of drug release from the conjugate was determined under physiological conditions by reversed phase HPLC. Within 14 days only 15% of the attached ADR was released from conjugate 4 . The antitumor activity of the conjugates was tested in vitro and in vivo against mouse P388 leukemia. Conjugate 4 proved to be 28 times less active than ADR in vitro, which could be explained from the slow drug-release. On the contrary 50% of the leukemic mice treated by 4 survived more than 60 days, whereas no mice given ADR alone or the admixture of ADR and DIVEMA survived 30 days. An antitumor activity of the polymeric conjugate better than that of the free drug was also observed in vivo with DM. Such a polymeric effect can be attributed either to the change in body distribution, the difference in pharmacokinetics, or the slow drugrelease. 相似文献
88.
Keisuke Izumi Hisashi Otsuka Keizo Furuya Akiko Akagi 《Virchows Archiv : an international journal of pathology》1979,384(3):263-267
Summary The carcinogenicity of 1,2-dimethylhydrazine dihydrochloride (DMH) by oral, intragastric and subcutaneous administration was examined in 339 BALB/c mice. Subcutaneous injection of DMH induced intestinal tumors in the lower colon of all mice. After oral administration it induced a high incidence of vascular tumors in the liver and soft tissues, but colon tumors were found in only 2 mice when given at a high dosage. On intragastric administration, it induced a fairly high incidence both of colon and vascular tumors. The sites and incidences of vascular tumors and squamous cell carcinomas of the perianal glands were also described.This work was supported in part by a Grant-in Aid for Cancer Research from the Ministry of Education, Japan. 相似文献
89.
Hiroshi Takahashi Nobuo Tsuda Shuichi Fujita Fumiaki Tezuka Haruo Okabe 《Pathology international》1990,40(9):655-664
Fifty-four adenoid cystic carcinomas (ACC) arising in major and minor salivary glands as well as in normal salivary glands were studied by immunohistochemistry for the presence of vimentin, neuron specific enolase (NSE), α1 -antichymotrypsin (α1 -ACT) and α1 -- antitrypsin (α1 -- AT). Five patterns of histological differentiation were found in ACC, and for the cellular components of each, it was possible to establish a special immunohistochemical profile. In ACC, vimentin-positive cells were observed in the outer tubular, cyst-lining and small angular cells. NSE was positive in the myoepithelial cells of normal salivary gland. Neoplastic cells of ACC showed NSE positivity mainly in the small angular cells and partly in the duct luminal cells. α1 -ACT was localized in the intercalated duct cells and serous acinar cells of normal salivary gland, and in the duct luminal cells of ACC. α1 -AT could not be detected in any of the epithelial cells of normal salivary gland. In ACC, eosinophilic hyaline material in the cribriform spaces was positive for α1 -AT, but no positivity was demonstrated in tumor cells. The present study showed that there are at least two populations of tumor cells in ACC: duct luminal cells that express α1 -ACT, thus indicating their ductal character, and small angular cells that express vimentin, characteristic of non-luminal cells. Moreover, our results indicate that α1 -AT is a useful marker of basement membrane-like material. 相似文献
90.
Masafumi Ito Atsuko Nakagawa Atsuo Nakayama Yutaka Uno Izumi Takahashi Junpei Asai 《Pathology international》1990,40(2):149-152
Malignant salivary gland tumors in children are very rare. This report describes the autopsy of a child with parotid gland cancer. The patient, a 10 month old girl, was admitted to the Nagoya First Red Cross Hospital with facial nerve palsy. lncisional biopsy of a post-auricular tumor was performed, and undifferentiated carcinoma was diagnosed. The patient died 6 months later of respiratory failure due to pulmonary lymphangitis carcinomatosis. Light and electron microscopic and immunohistochemical examinations of the tumor tissue were performed. The tumor cells were arranged in a medullary, sheet-like manner. Keratinization or mucus lakes were not observed. PAS-alcian blue staining demonstrated intracytoplasmic mucus as granules, and also small intercellular droplets of mucus that might otherwise have been unnoticed. Ultrastructurally, some of the tumor cells had tonofilament-like keratin filaments, and also small hollow spaces bounded by microvilli and containing secretory particles. These were stained by antisera against CEA and keratin. These findings are suggestive of differentiation to mucoepider-moid carcinoma. We also review and discuss malignant salivary tumors of epithelial origin in children. Acta Pathol Jpn 40: 149–152, 1990. 相似文献