Search PubMed⌕ Search

Biomedical subjects

J L Allen

Publications and source records attributed to J L Allen.

97 records · Page 6Linked to original sources
PubMedDate not supplied

Liquid chromatographic determination of rotenone in fish, crayfish, mussels, and sediments.

An analytical procedure is described for determining residues of rotenone in fish muscle, fish offal, crayfish, freshwater mussels, and bottom sediments. Tissue samples were extracted with ethyl ether and extracts were cleaned up by gel permeation chromatography and silica gel chromatography. Sediment samples were extracted with methanol, acidified, partitioned into hexane, and cleaned up on a silica gel column. Rotenone residues were quantitated by liquid chromatography, using ultraviolet (295 nm) detection. Recoveries from sediment samples fortified with rotenone at 0.3 microgram/g were 80.8%, whereas recoveries from tissue samples fortified with 0.1 microgram/g ranged from 87.7 to 96.8%. Samples fortified with 0.3 microgram/g and stored at -10 degrees C for 6 months before analysis had recoveries ranging from 83.2 to 90.5%. Limits of detection were 0.025 microgram/g for sediments and 0.005 microgram/g for tissue samples.

Animals↗
PubMedDate not supplied

Subcutaneous filariasis (Pelecitus sp.) in a yellow-collared macaw (Ara auricollis).

Clinical manifestations of subcutaneous filariasis in a yellow-collared macaw (Ara auricollis) included lameness induced by subcutaneous nodule formation, which was attributed to the presence of the filarial parasite Pelecitus sp. Following anthelmintic and corticosteroid therapeutic failure, the problem was resolved by surgically removing the adult worms.

Animals↗
PubMedDate not supplied

Determination of malachite green residues in the eggs, fry, and adult muscle tissue of rainbow trout (Oncorhynchus mykiss).

Malachite green, an effective antifungal therapeutant used in fish culture, is a known teratogen. We developed a method to simultaneously detect both the chromatic and leuco forms of malachite green residues in the eggs, fry, and adult muscle tissue of rainbow trout (Oncorhynchus mykiss). Homogenates of these tissues were fortified with [14C] malachite green chloride and extracted with 1% (v/v) acetic acid in acetonitrile or in methanol. The extracts were partitioned with chloroform, dried, redissolved in mobile phase, and analyzed by liquid chromatography (LC) with postcolumn oxidation of leuco malachite green to the chromatic form. LC fractions were collected every 30 s for quantitation by scintillation counting. Recoveries of total [14C] malachite green chloride residue were 85 and 98% in eggs fortified with labeled malachite green at concentrations of 0.5 and 1.00 microgram/g, respectively; 68% in fry similarly fortified at a concentration of 0.65 microgram/g; and 66% in muscle homogenate similarly fortified at a level of 1.00 microgram/g. The method was tested under operational conditions by exposing adult rainbow trout to 1.00 mg/L [14C] malachite green chloride bath for 1 h. Muscle samples analyzed by sample oxidation and scintillation counting contained 1.3 and 0.5 microgram/g total malachite green chloride residues immediately after exposure and after a 5-day withdrawal period, respectively.

Animals↗