The genotoxicity of ptaquiloside (PT), recently isolated from bracken fern and shown to be carcinogenic, was examined by means of the hepatocyte primary culture/DNA-repair test. PT elicited clear unscheduled DNA synthesis with a dose-response effect. The result indicates that PT is a genotoxic carcinogen.

Animals↗

PubMedDate not supplied

Effects of a synthetic polyprenoic acid (E-5166) on the gap junction of rat hepatocytes treated with liver tumor promoters, phenobarbital, and p,p'-dichlorodiphenyltrichloroethane.

Effects of in vivo exposure to the synthetic polyprenoic acid, 3,7,11,15-tetramethyl-2,4,6,10,14-hexadecapentaenoic acid (E-5166) using 6 groups of rats treated simultaneously or individually with phenobarbital (PB) or with p,p'-dichlorodiphenyltrichloroethane (DDT) on the gap junctions of hepatocytes were examined by freeze-fracture analysis. Experimental groups were as follows: Group 1, basal diet alone; Group 2, E-5166 treatment; Group 3, 0.05% PB diet; Group 4, PB diet and E-5166 treatment; Group 5, 0.05% DDT diet; and Group 6, DDT diet and E-5166 treatment. E-5166 was given by gavage (40 mg/kg body weight, 3 times/wk). Experimental diets and E-5166 were started at 6 wk of age. All animals were sacrificed at 2 wk after the start of the experiments. The density of gap junctions in PB- or DDT-treated rats was higher and that in E-5166-treated rats was lower than that in controls. The density of gap junctions in rats given PB and E-5166-/or DDT and E-5166-treated rats was slightly increased when compared to controls. The average area of gap junctions in DDT- or PB and E-5166-treated rats was significantly smaller than in controls (p < 0.005), although no statistical differences were found among PB-, E-5166-, and DDT and E-5166-treated rats and controls. Unit area of gap junctions to membrane area in rats given E-5166, DDT, or PB and E-5166 was lower than in controls. However, the unit area of gap junctions in DDT and E-5166-treated rats did not differ from in controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMedDate not supplied

Cytologic appearance of carcinosarcoma (malignant ameloblastoma and fibrosarcoma) of the maxilla. A case report.

The cytologic appearance of a carcinosarcoma (malignant ameloblastoma and fibrosarcoma) of the maxilla in a 63-year-old man is described. On his first admission the diagnosis of malignant ameloblastoma was made on biopsy. After five surgical excisions, radiotherapy and chemotherapy, the diagnosis was changed to carcinosarcoma because the stromal cells of the tumor had become malignant. Aspiration biopsy cytology of the tumor, with a cystic lesion found at the left suborbital area, revealed malignant epithelial cells, indicating malignant ameloblastoma. Imprint smears of both surgically resected and autopsy material showed two types of malignant neoplastic cells, of epithelial and mesenchymal origin.

Ameloblastoma↗

PubMedDate not supplied

Patch angioplasty of the superior vena caval obstruction (case reports with long follow-up results).

Four cases of the superior vena caval obstruction caused by mediastinal tumor and fibrous mediastinitis are presented. Palliation was achieved by resection of tumor or scar tissue and placing a Teflon or autogenous vein patch to the resected defect of the superior vena cava. One of the patients died of metastasis at 8 months postoperatively, but patency of the patch graft was confirmed. The other three are alive and well at 14, 14 and 11 years, respectively. Continued patency has been confirmed by venographies in two of them.

Adult↗

PubMedDate not supplied

Ki-1-positive large cell anaplastic lymphoma diagnosed by urinary cytology. A case report.

Cytomorphologic and immunocytochemical findings in urinary cytology in a case of Ki-1-positive large cell anaplastic lymphoma in the left cervical region in a 42-year-old man are reported. Smears stained with Papanicolaou or Wright-Giemsa stain showed a cytomorphologic spectrum that varied from immunoblastlike cells to large neoplastic cells with pleomorphic nuclei and vacuolated cytoplasm. Neoplastic cells with multilobulated, bizarre nuclei and mitosis were also observed. Immunocytochemistry on urinary sediments showed that the tumor cells were of a "null" phenotype and strongly expressed the Ki-1 antigen and "activation" markers of HLA-DR, Tac (CD25) and OKT9 (CD71). Histology and immunohistochemistry confirmed these findings.

Adult↗