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Biomedical subjects

G D Mills

Publications and source records attributed to G D Mills.

25 records · Page 2Linked to original sources
PubMed1980

Indomethacin enhancement of TPA tumor promotion in mice.

Skin tumor promotion in mice by 12-O-tetradecanoylphorbol-13-acetate (TPA) is characterized by hyperplasia and inflammation. Based on the inhibitory effect of the steroidal anti-inflammatory drugs, non-steroidal agents, such as indomethacin, were also expected to show some degree of inhibition; however, repeated tumor experiments demonstrate that indomethacin enhances TPA promotion in a dose-response manner. A time-of-application effect was evident such that indomethacin given 2 h prior to TPA resulted in the greatest enhancement. Flurbiprofen was also observed to enhance promotion slightly.

Animals↗
PubMed1973

Insect juvenile hormones: highly potent synthetic mimics.

The substitution of a 7-alkoxy group for the 6,7-epoxy moiety in aryl terpenoid ethers having high juvenile hormone activity has produced several compounds exceptionally active against Tenebrio molitor. The most potent compound [7-ethoxy-1-(p-ethylphenoxy)-3,7-dimethyl-2-octene, called JH-25] is active at the level of 10 picograms per insect, or about 100 times more active than other promising juvenile hormone mimics so far reported. Compound JH-25 was also active against Tribolium confusum.

Biological Assay↗
PubMedDate not supplied

Naturally occurring insect growth regulators. II. Screening of insect and plant extracts as insect juvenile hormone mimics.

Ethereal extracts prepared from the larvae, pupae, or eggs of 10 species of insects and from various parts of 343 species of higher plants were screened for juvenilizing effects against Tenebrio molitor and Oncopeltus fasciatus. Activity in both species was shown by an extract of the larvae of the stable fly, Stomoxys calcitrans, whereas an extract of the pupae was active in O. fasiatus only. Extracts of two plant species (Echinacea angustifolia roots and Chamaecyparis lawsoniana seeds) showed high juvenilizing activity in T. MOLITOR, AND EXtracts of five plant species (Clethra alnifolia stems, leaves, and fruits, Sassafras albidum roots and root bark, Eucalyptus camaldulensis stems and bark, Pinus rigida twigs and leaves, and Iris douglasiana roots, stems, and fruits) were highly active in O. fasciatus an extract of Tsuga canadensis leaves showed lower activity in this insect. Extracts of 16 species of plants showed high insecticidal activity (mortality) in O. fasciatus but lacked juvenilizing properties in both species of test insects.

Animals↗
PubMedDate not supplied

Naturally occurring insect growth regulators. III. Echinolone, a highly active juvenile hormone mimic from Echinacea angustifolia roots.

A compound, C14H24O2, which induces strong juvenilizing effects in the yellow mealworm, Tenebrio molitor L., following topical application to the pupal stage, was isolated in pure form from the roots of Echinacea angustifolia DC and tentatively identified as dextrorotatory (E)-10-hydroxy-4,10-dimethyl-4,11-dodecadien-2-one. The compound has been named echinolone.

Biological Assay↗