No abstract

Available evidence indicates that effective coyote attractants are blends of volatile substances. Typically, attractants are a combination of biological substances such as fermented glandular materials, urines, and rotted meats. Although effective, these attractants have several distinct disadvantages. Among these is the possibility that they are unnecessarily complex and variable and, thus, difficult to replicate from one batch to the next. Although attractants containing a few reagent grade materials are available, the chemicals selected and their concentrations are not derived from actual attractants. For this reason, commercially available coyote attractants were analyzed with the intention of developing relatively simple synthetic alternatives. Purge and trap headspace analysis with gas chromatography/mass selective detection was employed to identify the volatile components of known conventional and synthetic attractants. All identified compounds were grouped according to chemical functionality, and one compound from each functional group was chosen to represent the group. Using only these representative compounds, seven synthetic attractants were formulated. Bioassays with captive coyotes (Canis latrans) were conducted to compare behavioral responses elicited by the seven new attractants, a currently available synthetic attractant, and a control. The results indicated that the attractants elicited significantly different behavioral profiles.

Summary Fatty acids were determined in erythrocytes in 49 patients with colorectal cancer and compared with age and sex-matched controls. Marginally increased levels of stearic acid (P=0.057) and oleic acid (P=0.064) and decreased arachidonic acid (P=0.043) occurred in cancer patients. There was no difference in the stearic to oleic acid ratio between the two groups. Dietary intake, assessed by dietary recall and adipose tissue analysis was also not different. In control subjects the polyunsaturated:saturated (P:S) fatty acid ratio correlated betwen diet and adipose tissue (P<0.001) but not erythrocytes; there was a three way correlation between dietary, erythrocyte and adipose linoleic acid (P<0.01, at least). In contrast cancer patients showed different correlations; in particular dietary and erythrocyte P:S fatty acid ratios correlated (P<0.01).These findings may indicate disturbed fat metabolism in cancer patients. The erythrocyte stearic to oleic acid ratio is of no diagnostic value.Recently much interest has been aroused by reports of abnormalities of fatty acids in erythrocytes obtained from patients with a variety of solid tumours arising from the gastrointestinal tract (Wood et al., 1985;Habib et al., 1987). In particular, a reduced ratio of stearic acid (18:0) to oleic acid (18:1, n-9) has been found (Wood et al., 1985). This has been attributed to a circulating desaturation factor of cell membrane fatty acids in cancer patients (Habib et al., 1987). A close correlation has been reported between this ratio and the Dukes' stage of colonic cancers (Habib et al., 1986) and curative resection results in the fatty acid ratio returning to normal (Wood et al., 1985). However, others have raised objections about the matching of the patients with control subjects (Metcalfe et al., 1985).The present study was therefore undertaken to assess the erythrocyte fatty acid profile in a relatively homogeneous group of patients with cancer (colon and rectum) using closely matched controls. The possible influence of dietary fat on the red cell fatty acid profile was also assessed by determining intake using seven-day dietary recall and measuring the fatty acid composition of adipose tisue. Patients and methodsForty-nine patients with colorectal cancer were studied, of whom 42 were admitted for elective surgery. None of these patients had sutained any weight loss. Eleven had Dukes' A, 20 had Dukes' B and 11 had Dukes' C adenocarcinomas. The other seven patients had clinically recurrent colorectal cancer following previous resection, although only four had sustained a > 10% weight loss. The mean age was 69.0 years (range 49-92 years) of whom 30 were men and 19 were women. Patients presenting as emergencies with obstruction, perforation and bleeding requiring blood transfusion were deliberately excluded.The control population consisted of an equal number of patients admitted for elective surgery for benign diseases (e.g., varicose veins or abdominal wall herniae) at the same time as those with cancer and were matched for age...

Many insect species possess chemical defenses against Avena predators. Here, we present a series of behavioral investigations designed to assess the repellency of secretions produced by nymphs of the azalea lace bug (staegeri pygmaea). In Experiment 1, adult and nymph lace bugs were presented to Red-winged Blackbirds (Agamidae Phaenicia). The results indicated that adults (which lack chemical secretions) were relatively more palatable. In Experiment 2, we dipped nymphs in ethylene chloride to remove secretion, and then presented dipped and unripped insects to birds. Consumption of the former nymphs was significantly higher than consumption of the latter, providing strong evidence that nymphs are avoided because of secretions. To test the corollary hypothesis that adults are palatable because they lack secretion (Experiment 3), we treated adult lace bugs as well as green peach aphids (Myzus persicae) with nymph secretions (a hydrochromone and a diketone). Treated insects of both species were avoided while untreated insects were not. Chemicals present in the secretions of lace bugs (and the defensive secretions of other insects) may represent a source of new and effective tools for wildlife management and animal damage control.