PURPOSE: The purpose of this study is to find helpful MR findings for predicting a naplastic oligodendrogl lomas. MATERIALS AND METHODS: Retrospective analysis of 46 MR images and 37 CT scans was performed for 46 patients with pathologically-proven cerebral oligodendrogliomas. A neuropathologist graded the tumors as one of low-grade (n=16), intermediate-grade (n=l2), or anaplastic oligodendroglioma (n=18). MR imaging features were retrospectively analysed with respect to histologic grading of the tumors. RESULTS: Contrast enhancement was observed always in anaplastic group (17 /17), in a portion of intermediate-grade group (4/10) but not in low-grade group (0/14). Peritumoral edema was observed infrequently in anaplastic group (4/18) or intermediate-grade group (1/12). Cystic changes (25/46) or calcifications on CT Scans (14/37) were not related with histologic grading. Grossly identifiable hemorrhage was rare in this series (2/46). Among the various imaging features, only tumor enhancement and peritumoral edema were statistically significant for trend test (p<0.05). CONCLUSION: When considering the diagnosis of oligodendrogliomas, the presence of contrast enhancement or peritumoral edema is a helpful features suggesting anaplastic oligodendrogliomas.
Diagnosis ; Edema ; Hemorrhage ; Humans ; Loma ; Magnetic Resonance Imaging ; Oligodendroglioma* ; Retrospective Studies ; Tomography, X-Ray Computed

In the present study, quids from La Cueva de los Muertos Chiquitos (CMC) were subjected to ELISA tests for 2 protozoan parasites, Toxoplasma gondii (n=45) and Trypanosoma cruzi (n=43). The people who occupied CMC, the Loma San Gabriel, lived throughout much of present-day Durango and Zacatecas in Mexico. The known pathoecology of these people puts them into at-risk categories for the transmission of T. gondii and T. cruzi. Human antibodies created in response to these 2 parasites can be detected in modern saliva using ELISA kits intended for use with human serum. For these reasons, quids were reconstituted and subjected to ELISA testing. All test wells yielded negative results. These results could be a factor of improper methods because there is no precedence for this work in the existing literature. The results could equally be a simple matter of parasite absence among those people who occupied CMC. A final consideration is the taphonomy of human antibodies and whether or not ELISA is a sufficient method for recovering antibodies from archaeological contexts. An additional ELISA test targeting secretory IgA (sIgA) was conducted to further examine the failure to detect parasite-induced antibodies from quids. Herein, the methods used for quid preparation and ELISA procedures are described so that they can be further developed by future researchers. The results are discussed in light of the potential future of quid analysis.
Antibodies ; Enzyme-Linked Immunosorbent Assay ; Humans ; Immunoglobulin A, Secretory ; Loma ; Methods ; Mexico ; Parasites ; Saliva ; Toxoplasma ; Trypanosoma cruzi

BACKGROUND: Ethyl crbmate(EC) has been identified at low microgram quantities in various fermented beverages, destiled products and tobacco smoke. EC has long been known as a carcinogen. Oxidation of the ethyl group of EC is followed by dehydration to yield the carcinogen vinyl carbamate (VC). This is further oxidized to vinyl carbamate epoxide(VCO). VC and VCO proved to be much more carcirogenic than EC. OBJECT: The objective of this study is to compare the potency of carcinogenic ability and histologic changes in skin tumors induced by EC, VC, or VCO. METHODS: In this exeriment, the tumor induction was performed by painting the mouse skin once a week for five weeks with EC, VC and VCO solution, and then 12-0-tetradecanoyl-phorbol-13-acetate(TP2) was treated in the same manner twice a week for 35 weeks. We biopsied the skin at B 0, 15, 25, 30 and 35 weeks and stained the specimens with hematoxylineosin. RESULTS: The time period for the first appearance of papilloma was 6 weeks in the VC-TPA and VCO-TPA group, but, 15 weeks in the EC TPA group. The average number of papilloma showed a statistically sign.ficant difference after 15 weeks between the EC-TPA, VC-TPA and VCO-TPA group. The occurrence of keratoacanthoma and squamous cell carcinoma was 16 and 21 weeks respectively. Histologic changes, such as epidermal layers, pseudohorncysts, degree of hyperkeratosis, hypergranulosis, dysplasia and dyskeratotic cells were more prominent in the papil loma than in the non-papilloma lesion. Dermal changes disclosed similiar findings, that is, increased dermal thicknes, proliferation of vessels and hair follicles, and fibrosis of the dermis. Squamous cell carcinomis and keratoacanthomas were produced only in the VCO-TPA group. CONCLUSION: From the above results it is concluded that VC and VCO have a more potent carcinogenic potential than EC. Various skin tumors, such as papilloma, keratoacanthoma or squamous cell carcinoma were prorduced by the above carcinogens.
Animals ; Beverages ; Carcinogens ; Carcinoma, Squamous Cell ; Dehydration ; Dermis ; Fibrosis ; Hair Follicle ; Keratoacanthoma ; Loma ; Mice ; Paint ; Paintings ; Papilloma ; Skin* ; Smoke ; Tobacco ; Urethane*