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1.
Prostaglandins are inflammatory mediators that are believed to play an important role in the pathophysiology of periodontal disease. Prostaglandin H synthase (PGHS, EC 1.14.99.1) is the rate-limiting enzyme in prostaglandin biosynthesis. The enzyme exists as two separately encoded isoforms. PGHS-1 which is constitutively expressed and PGHS-2 which is induced by inflammatory stimuli. This is the first report describing the expression of the isoenzymes in gingival tissue from patients diagnosed with adult periodontitis. Tissue was fixed in an alcohol-based fixative and embedded in paraffin. Methods were developed using immunohistochemical controls, such that embedded sections could be processed and stained using isoform-specific antibodies and a peroxidase-antiperoxidase immunohistochemistry technique. Along with populations of mononuclear inflammatory cells, endothelial cells and fibroblasts, the gingival epithelial cell layer appears to be a rich and important source of prostaglandin production within the periodontium of patients with periodontitis as detected by this newly developed immunohistochemical staining technique for PGHS-1 and PGHS-2.  相似文献   
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Effects of ß-naphthonflavoe (ßNF) on theactivity of hepatic microsomal aflatoxin B1 (AFB1)-4-hydroxylase- the cytochrome P-450-dependent enzyme system which catalyzesthe metabolism of AFB1 to AFM1 - and on AFB1 induced in vivohepatocarcinogenesis were investigated in weanling male Fischerrats. A single i.p. injection of ßNF in doses of 20mg/kg and 150 mg/kg induced AFB1 -4-hydroxylase 3- and 4-fold,respectively, 48 h post injection. Feeding of diet containing0.01% ßNF for a period of 9-weeks induced AFB1 2-fold.AFB1, given by intubatlon in a dose of 25 µg five times/weekfor 8 weeks, produced 42 weeks later a 100% incidence of liverlesions (neoplastic foci, nodules or tumors), but feeding ßNFin diet at a con centration of 0.015% for one week prior toand during the 8 weeks of AFB treatment inhibited AFB1 hepatocarcinogenesis by -7%. These results are in accord with the suggestionthat AFB1 induction may be associated with the inhibition ofAFB1 carcinogenesis, possibly occurring as a consequence ofaccelerated detoxi-fication of AFB1 via its conversion to AFM1  相似文献   
4.
Archival material from 47 patients with primary squamous cell carcinoma of the head and neck (SCCHN) was studied immunohistochemically for the presence of nm23-H1 protein. Our data indicate that nm23-H1 protein expression is a common event in SCCHN and that there is a trend toward correlation of increased expression of nm23-H1 with increasing tumor size (p = 0.072). The results also show that when adjusting for age and cause of death, there tended to be an inverse relationship between overall survival and the expression of nm23-H1 gene in the primary tumor (p = 0.088).  相似文献   
5.
Congenital sacrococcygeal teratoma SCT is the most common germ cell tumor of infancy and childhood with a female preponderance. Most SCTs are diagnosed at birth, are benign, and consist of fully differentiated, mature tissues. Tumorigenesis of SCTs remains poorly understood. Almost nothing is known about possible oncogene activation or tumor suppressor inactivation in these rare tumors. We describe the presence of various oncoproteins and tumor suppressor proteins in eight cases of congenital SCT. The following oncogenes were examined: ras family c-H-, c-N-, and c-K-ras , early genes fos, jun , and tumor suppressor genes p53 and nm23-H-1 . There was no relationship between the intensity of expression of these oncoproteins and tumor suppressor genes and the following parameters: tumor size, age, and survival of the patients. We did not observe any difference, however, between the expression of the examined oncogenes and tumor suppressor genes nm23 and p53 in immature and mature teratomas. Our findings suggest that the ras family of oncogenes, fos and jun oncogenes, and nm23 and p53 tumor suppressor genes are present in congenital SCT, indicating a possible role in genesis and development of these tumors.  相似文献   
6.
Fifty-three patients with T1 squamous cell cancer of the floor of mouth and ventral surface of the tongue with a known clinical outcome were retrospectively analyzed and arbitrarily divided into “aggressive” and “nonaggressive” groups based on their clinical behavior. Various host and tumor factors were then evaluated in an attempt to determine whether the tumor behavior could have been predicted. The paraffin-embedded tumor specimens were evaluated for tumor differentiation, tumor thickness and tumor invasion, microvessel density, and p53 expression. In addition, a composite morphologic grading score was obtained by combining cell differentiation, nuclear polymorphism, mitosis activity, depth of infiltration, type of infiltration, and lymphatic infiltration. No single technique appeared capable of identifying “aggressive” behavior, although possibly an evaluation of composite factors might show promise in the future.  相似文献   
7.
Correlation of tumor-cell growth in four semisolid systems   总被引:1,自引:0,他引:1  
The correlation of the colony growth of cells disaggregated from human melanoma, sarcoma, lung, and ovarian carcinomas were studied in four different semisolid tissue culture assays: (a) the soft agar assay of Pluznik and Sachs; (b) the soft agar assay of Hamburger and Salmon; (c) the soft agar-methyl cellulose assay of Buick et al.; and (d) the methyl cellulose assay of Ogawa et al. There was no colony growth of tumor cells achieved in 15 of 15 cases assayed in Ogawa's methyl cellulose assay. The plating efficiency of the above mentioned tumors was similar in the assays of Pluznik and Sachs, Hamburger and Salmon, and Buick et al. However, the tumor take rate differed among these three systems. The assay of Buick et al. appears potentially useful for analysis of the biology of human tumors.  相似文献   
8.
Summary The reactivity of D-14 monoclonal antibody (mAb) to a specific epitope of carcinoembryonic antigen (CEA) was evaluated on formalin-fixed, paraffin-embedded tissues. A total of 52 normal tissues, 90 colorectal carcinomas and 127 non-colorectal neoplasms were tested using the peroxidase/antiperoxidase technique. D-14 mAb did not react with normal tissues apart from producing a weak staining of normal colonic glands immediately adjacent to the neoplastic structures. All 61 primary and 29 metastatic colorectal carcinomas expressed the carcinoembryonic antigen. However, there was considerable heterogeneity in cellular antigen expression in both primary and metastatic colorectal carcinomas with 10%–99% of tumor cells staining. Of 22 stomach adenocarcinomas, 14 were also immunoreactive, as were 2 of 5 pancreatic carcinomas. Only 6 of 100 neoplasms of non-gastrointestinal origin expressed weak to moderate immunoreactivity. In 7 cases, colorectal micrometastases not recognized in conventional hematoxylin and eosin slides could be identified with D-14 mAb. The specificity of this antibody could be used in differentiating colorectal carcinomas from other types of tumors, including adenocarcinoma from other sites.This paper was presented at the 1989 Annual Meeting of the American Association for Cancer Research Inc., San Francisco, California  相似文献   
9.
Abstract

Background/Objectives: Heterotopic ossification (HO) is a frequent, irreversible complication afterspinal cord injury (SCI). The objective of this article is to explain the etiology of HO; present new advances in prevention, diagnosis, and management of this complication; and provide a suggested algorithm for clinical management.

Etiology: Although still hypothetical, trauma and overexpression of bone morphogenic protein(s) in traumatized soft tissue appear to play important roles as initiating factors of HO.

Prevention: Preventive use of nonsteroidal antiinflammatory agents (NSAIDs) reduces the incidence of HO by a magnitude of 2 to 3.

Management: Early determination of serum creatine phosphokinase may have a diagnostic value in predicting the onset and severity of HO, and an NSAID may be added to etidronate therapy in the initial inflammatory phase of HO formation until C-reactive protein Ieveis return to normal range. Surgery is indicated in a subset of patients, and a regimenthat includes radiation therapy may prevent postoperative recurrence.

Conclusion: Significant progress has been made in the early prevention and management of HO. Further studies are needed to elucidate the etiology.  相似文献   
10.
The distinction between primary ovarian tumors and metastatic cancers to the ovary is frequently ambiguous. Recently, we reported that the D-14 monoclonal antibody (MAb), which is directed against a specific epitope of carcinoembryonic antigen (CEA), always reacts with colorectal adenocarcinomas and only rarely with neoplasms of non-gastrointestinal origin [J. Cancer Res. Clin. Oncol. 116, 51-56 (1990)]. We report here an analysis of the reactivity of four different anti-CEA MAbs with formalin-fixed tissue sections of human primary and metastatic colorectal and ovarian carcinomas. The four monoclonal antibodies employed were D-14, CEJ065, ZCEA1, and SP-625. D-14, CEJ065, and SP-625 MAbs reacted with essentially every colorectal adenocarcinoma. In contrast, ZCEA1 was the least reactive and 10 tumor samples showed no reactivity to this MAb. All four anti-CEA MAbs demonstrated scarce immunoreactivity with ovarian carcinomas and appear to be useful for distinguishing between ovarian carcinoma and colorectal metastasis to the ovary. Adenocarcinomas of the stomach and breast were also examined to determine CEA reactivity with the D-14 MAb, since these tumors need to be considered in the differential diagnosis of an ovarian mass. The majority of stomach adenocarcinomas were immunoreactive. In contrast, only 3 of 36 breast carcinomas were weakly immunoreactive, indicating that D-14 MAb is of no assistance in identifying breast carcinoma metastasis to the ovary.  相似文献   
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