Molecular cloning and nucleotide sequence of a new P450 gene, CYP319A1, from the cattle tick, Boophilus microplus.

We have isolated and sequenced a novel P450 gene (CYP319A1) from the cattle tick, Boophilus microplus. The CYP319A1 cDNA encodes a protein of 531 amino acids with an estimated molecular weight of 60.9k.

Cloning and sequencing of a putative acetylcholinesterase cDNA from Boophilus microplus (Acari: Ixodidae).

Using a strategy based on degenerate primers derived from acetylcholinesterase (AChE) from other species, we cloned and sequenced a putative AChE cDNA from the southern cattle tick, Boophilus microplus (Canestrini). The sequence has a high degree of homology to sequences of AChE from other species reported in the GenBank. The open reading frame of 1,689 bp, corresponding to a deduced sequence of 563 amino acids, has conserved regions and features shared by the AChE family, necessary for its catalytic activity.

Sequence analysis of the knockdown resistance-homologous region of the para-type sodium channel gene from pyrethroid-resistant Boophilus microplus (Acari: Ixodidae).

Using reverse transcription polymerase chain reaction and degenerate oligonucleotide primers, a partial para-homologous sodium channel cDNA was obtained from the southern cattle tick, Boophilus microplus (Canestrini). The cDNA sequence encoded the region in which knockdown resistance (kdr)-type mutations have been identified in numerous insect species. Comparison of deduced amino acids from the cDNA sequence showed high similarity with sodium channels from other species, particularly in highly conserved repeat domains of the sodium channel.

Characterization and molecular cloning of a glutathione S-transferase gene from the tick, Boophilus microplus (Acari: Ixodidae).

A glutathione S-transferase (GST) was purified from the larval cattle tick, Boophilus microplus (Acari: Ixodidae), by glutathione-affinity chromatography. The purified enzyme appeared as a single band on SDS-PAGE and has a molecular mass of 25.8 kDa determined by mass spectrometry.

Identification of a point mutation in the para-type sodium channel gene from a pyrethroid-resistant cattle tick.

To investigate the molecular mechanism of resistance to pyrethroids in the southern cattle tick, Boophilus microplus, we have obtained and sequenced a partial para-homologous sodium channel cDNA from susceptible and pyrethroid-resistant tick strains. A point mutation that results in an amino acid change from Phe to Ile was identified in the highly conserved domain IIIS6 of the homologous sodium channel from ticks that are highly resistant to pyrethroid acaricides. This mutation is at a location different from those reported in the same gene in pyrethroid-resistant insects.

Comparison of genomic DNA in various strains of Boophilus microplus (Acari: Ixodidae).

The conventional method of identifying acaricide resistance in a suspect tick population by the United Nations Food and Agriculture Organization packet assay is a laborious and time-consuming process. DNA probes have been demonstrated as rapid and accurate tools for detecting pesticide resistance in insect species. Random-amplified polymorphic DNA (RAPD) has been used by other groups to differentiate species of mosquitoes and populations within a mosquito species.

Lack of dietary calcium effect on chlordecone increased white blood cell count, total iron, and iron-binding capacity in serum of rat.

Male Sprague-Dawley rats were treated with 0, 1, 10, 50, and 100 ppm of chlordecone (Cd) mixed in calcium-sufficient (Ca-S) or calcium-deficient (Ca-D) diet for 15 days. The control rats fed with Ca-D diet exhibited a significant increase in white blood cell (WBC) counts compared to the rats fed with Ca-S diet. Dietary calcium (Ca), however, did not elicit any significant effect on total iron content and iron-binding capacity (transferrin) of control rats, whereas Cd at higher concentrations significantly increased WBC counts, total iron, and iron-binding capacity in serum of both Ca-S and Ca-D rats.

Isopimpinellin is not phototoxic in a chick skin assay.

Synthetic isopimpinellin (5,8-dimethoxypsoralen), confirmed to contain as impurities only trace quantities at most of psoralen, bergapten (5-methoxypsoralen) and xanthotoxin (8-methoxypsoralen), is not phototoxic when tested in a chick skin bioassay system. These findings are at variance with earlier studies showing isopimpinellin to be phototoxic against chick skin and support the conclusion that isopimpinellin is photobiologically inactive. As recently proposed by others, the several reports of isopimpinellin photoactivity are most likely attributable to contamination by small amounts of highly active psoralens such as bergapten or xanthotoxin.

Influence of dietary calcium on chlordecone-induced biochemical changes in serum of rat.

Male, Sprague-Dawley rats were treated with different (1, 10, 50, and 100 ppm) concentrations of chlordecone (Cd) in calcium-sufficient (Ca-S) or calcium-deficient (Ca-D) diet for 15 days. No significant changes in serum total proteins were observed. However, serum nonprotein nitrogen compounds (urea, uric acid, and creatinine) and glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, creatine kinase, and alkaline phosphatase were significantly increased at 50 and 100 ppm of Cd.

Metabolism of [14C]propionic acid in broiler chicks.

Broiler chicks were given 4 or 120 mumol propionic[1-14C] acid by gavage to determine its chemical fate and distribution of radiolabel among organs and tissues [foregut (crop, gizzard, and proventriculus), intestine (small and large), ceca, liver, and serum]. At 15 and 60 min postgavage, most of the extractable radiolabel remaining in the chicks was found in the foregut. Significantly higher percentages of the administered radiolabel were detected at 15 min in the serum and liver extracts of chicks given 120 mumol of propionic acid than in chicks given only 4 mumol.

The toxic effects of mature flatpea (Lathyrus sylvestris L cv Lathco) on sheep.

The toxic effects of mature, seed-bearing flatpea (Lathyrus sylvestris L cv Lathco) hay on sheep was studied in a feeding trial with 25 adult ewes. Five ewes were barren; 20 were in the last 10 w of pregnancy. The ewes were blocked by weight and reproductive status for assignment to treatment groups.

The effects of dietary calcium and chlordecone on cholinesterase, triglycerides, low density lipoproteins, and cholesterol in serum of rat.

Male, Sprague-Dawley rats were treated with 0, 1, 10, 50, 100 ppm chlordecone (Cd) mixed in calcium-sufficient (Ca-S) or calcium-deficient (Ca-D) diet for 15 days. A significant decrease in body weight gain was observed in 100 ppm of Cd-treated rats. Cholinesterase (ChE) activity was significantly decreased in serum of Ca-D rats.

Fate of [(14)C]xanthotoxin (8-methoxypsoralen) in laying hens and a lactating goat.

The metabolism of xanthotoxin, a naturally occurring furanocoumarin photosensitizer, was studied in laying hens and a lactating goat treated with single oral doses equivalent to 10 mg xanthotoxin/kg of body weight. Within 48 h, essentially all of the administered radiocarbon was eliminated in the excreta of the laying hens, while in the goat 92% and 3% were excreted in the urine and feces, respectively. Radiocarbon residues in the milk, egg white, and egg yolk were low.

The individual and combined toxicity of kojic acid and aflatoxin in broiler chickens.

The individual and combined effects of kojic acid and aflatoxin were studied in male broiler chicks (Peterson x Hubbard). The experiment had a two by two factorial arrangement of treatments with dietary treatments of 0 and 2,500 mg kojic acid/kg feed and 0 and 2.5 mg aflatoxin/kg feed.

Comparative fate of the tritiated trichothecene mycotoxin, T-2 toxin, in chickens and ducks.

A tritiated preparation of the trichothecene mycotoxin, T-2 toxin, was administered as a single oral dose to 21-day-old male broiler (Hubbard x Hubbard) chickens and White Pekin ducks. There were few significant differences between the two species in metabolism, tissue retention, and excretion of T-2 toxin and its metabolites. On the basis of the data obtained, the differences in toxicological sensitivity to T-2 toxin known to exist between these two species cannot likely be attributed to differences in the metabolism or elimination of T-2 toxin from the body.

Toxic effects of kojic acid in the diet of male broilers.

The toxicological effects induced by the administration of kojic acid were characterized in young male broiler chickens (Hubbard x Peterson). The experimental design consisted of six dietary treatments of kojic acid (0, .5, 1, 2, 4, and 8 g/kg feed) and four replicates of 10 broilers per replicate.

Induction of glutathione S-transferases in genetically inbred male mice by dietary ethoxyquin hydrochloride.

1. Constitutive and ethoxyquin hydrochloride (EQ-HCl)-induced hepatic glutathione (GSH) S-transferase, GSH reductase, and GSH peroxidase activities were determined in 5 strains of 8-10 week old inbred male mice. 2.

Fate of [14C]coumaphos after dermal application to lactating goats as a pour-on formulation.

Two lactating Nubian goats were dermally treated with [14C]coumaphos (O-[3-chloro-4-methyl-2-oxo-2H-benzopyran-7-yl] O,O-diethyl phosphorothioate) as a 4% active ingredient pour-on formulation. Doses were administered, along the dorsal midline from withers to sacrum, at a rate equivalent to 14 mg of coumaphos/kg of body weight. During the 7 days after treatment, an average of less than 0.

Constitutive and Aroclor 1254-induced hepatic glutathione S-transferase, peroxidase and reductase activities in genetically inbred mice.

1. Constitutive and Aroclor 1254-induced hepatic glutathione (GSH) S-transferases, GSH peroxidase and GSH reductase activities were determined in 12 strains of 8-10 week-old inbred male mice. 2.

Inhibition of macrophage adenylate cyclase by the alpha-methylene-gamma-lactone moiety of sesquiterpene lactones from forage plants.

Inhibition of murine macrophage adenylate cyclase activity by sesquiterpene lactones isolated from toxic forage plants was highly correlated with the presence of the alpha-methylene-gamma-lactone moiety on the molecule (ie, hymenovin and helenalin). Tenulin, a sesquiterpene lactone which does not contain this reactive moiety, caused minimal inhibition of the enzyme. Reaction of the alpha-methylene-gamma-lactone moiety of hymenovin and helenalin with cysteine decreased the number of reactive moieties available to alkylate the enzyme, thus decreasing the inhibition of adenylate cyclase by these 2 sesquiterpene lactones.

Dermatitis in grocery workers associated with high natural concentrations of furanocoumarins in celery.

A vesicular, peeling rash characteristic of a phytophototoxic dermatitis developed on the hands and arms of 30 of 127 grocery workers. The rash subsequently healed with residual hyperpigmentation. Produce workers had the highest attack rate, 100% (8 of 8, p less than 0.

In vitro metabolism of a linear furanocoumarin (8-methoxypsoralen, xanthotoxin) by mixed-function oxidases of larvae of black swallowtail butterfly and fall armyworm.

Studies were made of the comparative in vitro metabolism of [(14)C]xanthotoxin and [(14)C]aldrin by homogenate preparations of midguts and bodies (carcass minus digestive tract and head) of last-stage larvae of the black swallowtail butterfly (Papilio polyxenes Fabr.) and the fall armyworm [Spodoptera frugiperda (J. E.

Comparative metabolism of [(3)H]psoralen and [ (3)H]isopsoralen by black swallowtail (Papilio polyxenes Fabr.) caterpillars.

The comparative fate of tritiated preparations of a linear furanocoumarin (psoralen) and an angular furanocoumarin (isopsoralen) was determined in last-instar caterpillars of the black swallowtail butterfly (Papilio polyxenes Fabr.). Oral administration of either furanocoumarin at 5 μg/g is followed by rapid metabolism, primarily through oxidative cleavage of the furan ring, and the metabolites are rapidly excreted.

Fate of [14C]xanthotoxin (8-methoxypsoralen) in a goat and in bovine ruminal fluid.

A lactating Nubian goat was treated with [14C]xanthotoxin, a photosensitizing psoralen that occurs naturally in some phototoxic range plants, as a single oral dose equivalent to 10.0 mg of xanthotoxin/kg of body weight. The radiochemical was rapidly absorbed, metabolized, and excreted.

Fate and residues of [4-14C]estradiol-17 beta after intramuscular injection into Holstein steer calves.

Radiocarbon-labeled estra-1,3,5(10)-triene-3,17 beta-diol [4-14C-estradiol-17 beta; beta-estradiol] was suspended in commercial peanut oil and administered to each of three Holstein steer calves (142 to 170 kg body weight) by deep injection into neck muscle via 2.0 ml peanut oil carrier. The dosages were equivalent to .