Search

Aims: Expression of the v6 variant isoform of CD44 has been causally associated with the development of metastases. This study, using immunohistochemical techniques, examined the prognostic significance of CD44s and CD44v6 expression., Methods: A cohort of 109 women presenting with stage 2 breast cancer, with a minimum follow-up of 5 years, were assessed., Results: Eighty percent of patients demonstrated CD44v6 expression on immunohistochemical studies. CD44v6 expression in tissue sections was found to be independent of age, tumour size, grade, and lymph-node status. No significant association was demonstrated between CD44v6 expression and either disease-free or overall survival. Similar findings were observed for CD44s., Conclusions: CD44s and CD44v6 do not appear to be useful as prognostic indicators in early breast cancer. The increased expression of variant CD44 isoforms seen in breast neoplasia may merely be a marker for loss of control of alternative splicing within tumour tissue., (Copyright 2001 Harcourt Publishers Limited.)

The toxicity of Compound 1080 (sodium fluoroacetate) livestock protection collars (LPCs) to sheep was investigated. Lambs wearing punctured LPCs were observed to determine dermal toxicity, sheep were fed hay treated with LPC solution to find a lethal concentration, hay treated with a lethal concentration was subjected to sun and simulated rain to assess weathering influences, and sheep were held on pasture treated with LPC solution to evaluate grazing effects. Five lambs that wore punctured LPCs for up to seven days showed no dermal erythema or edema, but three died after ingesting 1080 from LPCs. All sheep died after eating 1.0 kg of hay treated with 3.75 ml, or more, of 1.0% LPC solution. Weathering 1.0 kg of hay treated with 3.75 ml of LPC solution in the sun for up to 12 weeks, reduced, but did not eliminate, toxicity; one inch or more of simulated rain eliminated toxicity. Survival of sheep in 250 m2 pens containing 1.1 m2 of forage treated with different amounts of LPC solution depended on the treatment and amount of treated forage consumed. LPC solution poses no dermal toxicity or irritation to sheep, and toxic effects on sheep from LPC solution on hay and forage was variable and situation dependent. Under conditions of exaggerated hazard, sheep can be poisoned by ingesting LPC solution, but adverse effects from normal LPC use are rare.

Tissues of coyotes and magpies administered known dosages of 1080 were analyzed for residues by an analytical method specifying gas chromatography and electron capture detection. The repeatability of the method was determined for the replicate analyses of coyote muscle tissue samples aged under different storage conditions. The average coefficient of variation (CV) was 6% for quadruplicate determinations of 1080 in fresh tissues, 12-14% for samples stored at - 10 degrees C for 30-60 days, and 24% for samples aged for 7 days at ambient temperatures. The larger CV value obtained for stored samples is attributed more to greater sample variability than to less precision of the analytical method. Residues of 1080 appear to be relatively stable in tissues; there was essentially no change in the concentration of 1080 in samples stored up to 28 days at ambient temperature. Residue levels in the muscle, heart, kidney, and intestine were comparable, slightly lower in the liver, and much higher in the stomach. The concentration of 1080 in the muscle tissue was related to the administered dosages. Correlation analyses of dosages and residue levels in coyote muscle tissue showed a correlation coefficient of 0.99 for 1080 administered by gavage, and 0.88 for 1080 administered by bait. A correlation coefficient of 0.99 was observed between dosages and mean residues in the breast muscle tissues of magpies. The average CV value was 3.5% for duplicate analyses of 1 g samples of magpie tissues.

During an 18-year period, 4.1% (34/831) of male deer (Odocoileus hemionus columbianus) killed on a field station during the autumn hunting season had velvet-covered, often misshapen antlers, and at least two deer had testicular atrophy (gonads from most deer were not available for examination). Testes from six similarly affected deer and several normal deer were compared histologically. Lesions ranged from hypocellularity of the semeniferous tubules and relative hyperplasia or degeneration of interstitial cells to complete connective tissue replacement of the testicular parencyma. Chronic vascular changes were present in several testes. The etiology and pathogenesis of the lesions were not determined.

Blood samples were obtained from native mammals and birds on a sheep range (Hopland Field Station) in northern California. Serums were tested for antibodies to Toxoplasma gondii by the indirect hemagglutination test. Of 382 deer that were tested from 1964 to 1973, 77 (20%) were seropositive for T gondii. Among 36 serums representing 6 species of wild carnivores (badgers, bobcats, coyotes, foxes, raccoons, and skunks), 18 (50%) were seropositive. All of the 5 bobcats tested were seropositive, with antibody titers ranging from 1:65,536. The testing of 175 serums from small wild mammals indicated antibody prevalence of 8% among jackrabbits, 6% among brush rabbits, and 2% among squirrels. None of the native mice tested was seropositive for T gondii. Of 120 native birds tested, 6 (5%) were seropositive. Of the resident domestic species of animals tested, antibodies were found in 1 of 7 domestic cats, 1 of 5 feral cats, 1 of 2 dogs, and 54 (13%) of 405 sheep.