Phytoplankton growth, dissipation, and succession in estuarine environments. Renewal proposal and annual summary report, August 1, 1977--July 31, 1978

Energy Technology Data Exchange (ETDEWEB)

Seliger, H H

1978-01-01

The directions of the research program in understanding the dynamics of the natural phytoplankton populations of the Chesapeake Bay, the methodology, the statistical analysis, and the description of the system are parallel to the requirements for environmental impact studies. Results are reported for the following studies: development of instrumentation and the synoptic isopleth methodology for relating the dynamic distributions of natural phytoplankton populations to water circulation patterns; phytoplankton cage experiments for assessment of nutrient dynamics; sub-lethal concentrations and effects of polycyclic aromatic hydrocarbons; and studies on concentration and time kinetics of induction of liver aryl hydrocarbon hydroxylase system in Fundulus heteroclitus by benzopyrene and 3-methyl cholanthrene. (HLW)

Studies on cross-immunity among syngeneic tumors by immunization with gamma-irradiated tumor cells

International Nuclear Information System (INIS)

Ito, Izumi

1977-01-01

In order to clarify whether cross-immunity among 3-methyl-cholanthrene (MCA)-induced sarcomas in C3H/He mice can be established or not, transplantations of syngeneic tumors were carried out in mice immunized with gamma-irradiated (13,000 rad 60 Co) tumor cells and in those immunized with living tumor cells thereafter. The following results were obtained. By using immunizing procedure with only gamma-irradiated tumor cells, a pair of tumors originating from one and the same mouse showed cross-resistance to each other. However, no such evidence was seen among tumors originating from different mice. Cross-immunity among syngeneic tumors originating from different mice could be clearly observed, when immunizing procedure using living tumor cells was added after the treatment with gamma-irradiated tumor cells. It was considered that common antigenicity among MCA-induced sarcoma cells was decreased by gamma-irradiation and that individual differences of tumor antigenecity were shown distinctly under such conditions. (auth.)

Therapeutic tests on methylcholanthrene-induced fibrosarcoma and transplanted fibrosarcoma of the mouse - clostridial oncolysis and its enhancement by high-frequency hyperthermia and X-rays

International Nuclear Information System (INIS)

Pirlet, T.

1982-01-01

Tests aimed at a conditioning of tumours by means of x-ray irradiation and high-frequency hyperthermia. Methyl cholanthrene-induced fibrosarcoma (IMCM) and its transplant version (T-IMCM) produced at the neck of NMRI-mice at a critical localization immediately next to vital organs, served as a test system since it is almost resistant to simple oncolysis. Individual therapy components were compared for their mutual enhancement of efficacy in 16 test groups, and the triple combination (Cl + X-ray + HFH) was tested in relapse application as well. A 2000-R-x-ray irradiation was followed by almost simultaneous 4 min HF heating and i.v. spore administration at 12 h intervals. Assessment criteria were tumour growth, survival rates and times, absence of recidivity and healing, analysis of post-mortem findings and dimension or duration of lyses. In addition, the two tumour types of induction and transplant tumour were compared. The typical course of clostridial oncolysis can be confirmed in principle. Results show that it is possible by means of additional physical methods as were applied, to increase the systemically apathogenic and selective therapy principle of rather negligible oncolysis to over 80% (IMCM) or 97% (T-IMCM). Concerning the MCA fibrosarcoma which is very resistant to clostridial oncolysis in this mouse-tumour model, marked prolongations of survival or healing are possible even in extremely critical localization. In principle, this provides the preconditions for including oncolysis in clinical studies in human medicine. (orig./MG) [de