Lethal and 'disturbing' temperatures in some fish species from lakes with normal and artificially elevated temperature

The mean lethal temperatures and 'disturbing' temperatures of 14 species of freshwater fish have been determined in field tests carried out on lakes unheated and heated by power-stations near Konin. The relationships between these parameters and the acclimation temperatures of fish in these lakes are analysed in relation to roach Rutilus rutilus (L.), rudd Scardinius erythrophthalmus (L.) and perch Perca fluviatilis (L.) and compared with the other published data for these species.     

Human pancreatic adenocarcinoma: In vitro and in vivo morphology of a new tumor line established from ascites

Summary A human pancreatic tumor cell line has been established from the ascites of a patient with histopathologically confirmed adenocarcinoma of the head of the pancreas and maintained for more than 12 months in the laboratory. Epitheloid tumor cell colonies, which resulted from primary tissue cultures of the ascitic cell component, were mechanically isolated by needle micromanipulation. Tumorigenicity was proven in athymic nude mice. Morphologically the pancreatic tumor epithelial cells grew to confluency with moderately tight adhesion to the culture plastic surface and with free-floating cells in the medium. Upon re-establishment of the tumoral xenograft in tissue culture, the epithelial cells retained their original morphology. Histologically the tumor grown in nude mice exhibited prototypic characteristics of the primary adenocarcinoma in the patient, producing abundant mucin and displaying a broad spectrum of glandular differentiation, which ranged from well to poorly differentiated adenocarcinomas with occasionally localized lymphocytic infiltrations. Furthermore, the tumor expressed carcinoembryonic antigen and human pancreas cancer associated antigen. This tumor line, designated AsPC-1, has been cultured for at least 10 passages in vitro and 3 in vivo. It represents a new model for human pancreatic cancer. This work was supported in part by Research Grant CA-18410 awarded by the National Cancer Institute through the National Pancreatic Cancer Project.     

Enhancement of T cell cytotoxic responses by purified human fibroblast interferon.

Purified polyribonucleotide-induced human fibroblast interferon (HFIF) was tested for its effects on proliferative and cytotoxic human T cell responses to alloantigens. The addition of HFIF (100 to 400 IFU/ml) to mixed leukocyte cultures decreased alloantigen-induced lymphocyte proliferative responses as determined by both recovery of responding cells and by 3H-thymidine incorporation into responding cells. However, HFIF, but not the mock interferon preparation, increased the cytotoxic response of T cells to allogeneic cells by 4- to 5-fold when expressed in terms of lytic units. Although fibroblast and leukocyte interferons have different physicochemical and biologic properties, the results reported here are in concert with previous findings concerning the effects of virus-induced leukocyte interferon on human T cell functions.     

Potentiation of the cell growth inhibitory effect of beta interferon by mopidamole

It was suggested that the antitumor effect of the interferons is based in part on their ability to stimulate increased cAMP production. We have explored the interaction of human fibroblastic beta interferon (HFIF) with a cAMP decomposition inhibitory pyrimido-pyrimidine derivative, Mopidamole (RA-233) in cultures of neoplastic and normal cell lines. Mopidamole potentiated the growth inhibitory effect of HFIF in cultures of ES-1 malignant melanoma cells, LNCaP prostatic carcinoma cells, RT-4 transitional carcinoma cells, HT-29 colon adenocarcinoma cells and in diploid fibroblast cells.