Thermodynamic aspects of development forTenebrio molitor L

Summary Predictions of the thermodynamics of irreversible processes are tested for the development and aging of an insect. Specific heat production and specific respiration rate decrease towards a steady state with deviations for the time of hatching of the imago.     

Inhibition of phorbol myristate acetate and phytohemagglutinin stimulation of human lymphocytes by 13-cis-retinoic acid and ethyl etrinoate

Summary The retinol analogues 13-cis-retinoic acid and ethyl etrinoate inhibit the mitogenic activity of phorbol myristate acetate and phytohemagglutinin on human lymphocytes. This inhibitory effect is greater against the stimulation with phorbol myristate acetate than with phytohemagglutinin.This work was supported by a grant from the National Cancer Institute of Canada. We would like to thank Hoffmann-La Roche, Canada, for providing the 13-cis-retinoic acid and the ethyl etrinoate.     

Acute physiological responses during blood substitution with colloidal gelatin in conscious rats

The effects of exchange-transfusion with a proprietary gelatin-based plasma volume expander, Haemaccel, have been investigated in conscious, chronically-catheterized rats. No adverse changes in basic cardiovascular or respiratory functions occurred during the procedure although an increase in intravascular fluid sodium but not potassium concentration was observed.     

In vitro esterification of plant sterols by the esterifying enzyme of the small intestine of rat

The in vitro esterification of plant sterols, beta-sitosterol, campesterol and stigmasterol, by the esterifying enzyme of the small intestine of rat was studied in the presence of saturated and unsaturated fatty acids. Campesterol esterification was highest, followed by sitosterol and stigmasterol irrespective of the type of fatty acid. Both campesterol and sitosterol esterification was greater with unsaturated fatty acids than with saturated fatty acids.     

Juvenile hormone active principle inAttacus atlas L

Summary The ether extract ofAttacus atlas L., subjected to an isotope dilution method for the determination of known insect juvenile hormones, revealed the presence of an active substance which has a similar chromatographic behaviour with the known JH-3, methyl (2E, 6E)-10, 11-epoxy-3, 7, 11-trimethyl-2, 6-dodecadienoate.The work was supported as a research training by Dr.R. Maag Ltd., CH-8157 Dielsdorf, Switzerland.     

Inhibition of tumor-induced angiogenesis and of tumor growth by activated lymphocytes

Summary Inhibition in angiogenesis (neo-vascularization) and of growth of a tumor piece graft in the anterior chamber of the eye of mice have been observed in the presence of activated syngeneic lymphocytes.Acknowledgment. The authors are thankful to ICMR, New Delhi, for financial assistance and to Mr N.C. Ghosh for illustration.     

The HIV tat gene induces dermal lesions resembling Kaposi's sarcoma in transgenic mice

When the human immunodeficiency virus transactivating gene under the control of the viral regulatory region is introduced into the germline of mice, skin lesions are induced that resemble Kaposi's sarcoma seen in AIDS. Our findings indicate that HIV could play a direct part in causing cancer.     

Pistia stratiotes L. in Nigerian waters

Summary Pistia stratiotes L., a perennial water weed found in natural water bodies in Nigeria, removes organic and inorganic nutrients as it grows and spreads in the waters. In a lake which received a variety of pollutants, the plant reduced oxidizable organic matter (4-h permanganate value) by 61%, the biochemical oxygen demand by 85.3%, ammonia nitrogen by 95.3% and water soluble phosphorus by 85%. The plant also removed other mineral matter.