Field populations of western corn rootworm, Diabrotica virgifera virgifera LeConte, were collected from three different sites (York Co., Phelps Co., and Saunders Co.) in Nebraska during 1996. Adult bioassays of these three populations were conducted with different concentrations of methyl-parathion and at a diagnostic concentration (1.0 microg/ml) to determine resistance levels among these popu...

The red yeast Rhodotorula mucilaginosa produced an esterase that accumulated in the culture supernatant on induction with triacetin. The enzyme was specific for substrates bearing an O-acetyl group, but was relatively nonspecific for the rest of the molecule, which could consist of a phenol, a monosaccharide, a polysaccharide, or an aliphatic alcohol. The esterase was more active against acetyl...

The objective of this study was to examine the alkaline, acidic phosphatase and nonspecific esterase activity in the epithelial cells of oviducts after exposure to polychlorinated biphenyls (PCBs) at the time of puerperium. PCBs were administered in the last days of pregnancy and during early puerperium. Animals in the experimental group were exposed to Delor 105 at a dose of 100 μg/kg/day and ...

Treatment of non-T/non-B human leukemic cell line REH with 5 X 10(-9) M 12-O-tetradecanoylphorbol-13-acetate (TPA) at 37 degrees resulted in their adherence to culture flasks by 24 to 36 hr and, after 72 hr, the entire surface of the flask/coverslips became covered with macrophage-like cells containing pseudopodia. Wright-Giemsa-stained untreated cells had blast morphology, whereas TPA-treated ...

The ges-1 gene of the nematode Caenorhabditis elegans codes for a nonspecific carboxylesterase that is expressed only in the intestinal lineage. This esterase has turned out to be a convenient biochemical marker for lineage-specific differentiation. In the present paper, we describe the production of several C. elegans strains that lack detectable activity of the ges-1 esterase. To isolate thes...