Sun-safe behavior and perceptions during winter sports: an Austrian study based on the Theory of Planned Behavior.

As a preventable disease, skin cancer is a public health issue in Austria. Most sun-safety studies focus on people's activities in summer, but little is known about sun-protective behavior in winter. Based on the Theory of Planned Behavior (TPB), this study examines psychological perceptions among people who engage in winter sports in Austria. Following a TPB-based belief elicitation study, a consequent survey was conducted among 114 participants (51.8% female; Mage = 29.54 years) in South Austria. Intention, attitude, subjective norm, perceived behavioral control, and risk perception showed strong and significant associations with sun-safe behavior among people who engage in winter sports. The TPB framework explained a large portion of variance in sun-safe behavior (75%) and intention (73%). Gender differences have been identified in TPB-variables as well as several beliefs. Based on the utility of the TPB, our findings suggest guidelines for sun-safety in winter sports settings. Gender differences are in line with previous research, highlighting the vulnerability of men to sun damage during winter sports.

Characterization of California sea lion polyomavirus 1: expansion of the known host range of the Polyomaviridae to Carnivora.

The genome of a novel polyomavirus first identified in a proliferative tongue lesion of a California sea lion (Zalophus californianus) is reported. This is only the third described polyomavirus of laurasiatherian mammals, is the first of the three associated with a lesion, and is the first known polyomavirus of a host in the order Carnivora. Predicted large T, small t, VP1, VP2, and VP3 genes were identified based on homology to proteins of known polyomaviruses, and a putative agnoprotein was identified based upon its location in the genome. Phylogenetic analysis of the predicted late region proteins found that the laurasiatherian polyomaviruses, together with Squirrel monkey polyomavirus and Murine pneumotropic virus, form a monophyletic clade. Phylogenetic analysis of the early region was more ambiguous. The noncoding control region of California sea lion polyomavirus 1 is unusual in that only two apparent large T binding sites are present; this is less than any other known polyomavirus. The VP1 of this virus has an unusually long carboxy-terminal region. A quantitative polymerase chain reaction was developed and utilized on various samples from 79 additional animals from either managed or wild stranded California sea lion populations, and California sea lion polyomavirus 1 infection was found in 24% of stranded animals. Sequence of additional samples identified four sites of variation in the t antigens, three of which resulted in predicted coding changes.

Dose verification after topical treatment of alligator (Alligator mississippiensis) eggs.

Numerous studies have used temperature-dependent sex determination in reptilian eggs to investigate potential developmental effects of exogenously applied substances. However, few studies have measured the dose carried across the eggshell. We report embryonic mortality and internal egg concentrations determined by gas chromatography-mass spectrometry two weeks after exposure of American alligator (Alligator mississippiensis) eggs to chlorinated organic pesticides via injection or topical application. Puncturing the eggshell for injection produced high mortality compared with unpunctured controls; therefore, further evaluation of this method was abandoned. Although higher than controls, mortality was much lower in eggs treated topically than in those injected. Transfer of chemicals across the eggshell was very low, highly variable, and did not correlate with the applied dose after topical application. These results are consistent with previous reports in the literature, casting doubt on whether a reproducible internal dose can be achieved in reptilian eggs by topical treatment.

Topical dose delivery in the reptilian egg treatment model.

Developing assays to detect endocrine-mediated toxicity from in ovo or in utero exposure is a current challenge in regulatory toxicology. Some species of reptiles exhibiting a unique mode of sex determination, in which the incubation temperature during a critical period determines gonadal sex, have been explored as an in ovo model to screen environmental contaminants for endocrine effects. We critically review published egg-exposure studies and conclude that data regarding the pharmacokinetics of topically applied substances are insufficient to validate dose-response relationships for the effects of chemicals on in ovo endocrine function or gender determination in reptiles. The insufficiencies in these data largely result from methodological failures, including lack of measurement verification, failure to investigate and control extraneous factors affecting the measurements, and lack of independent replication of results. Considerable additional research will be necessary to alleviate these methodological inadequacies. Given the current status of the data, topical treatment of reptilian eggs cannot be considered to be a valid means of establishing causal relationships between chemical treatment and biological outcome.

Influence of seasonality and exposure on the accumulation and reproductive effects of p,p'-dichlorodiphenyldichloroethane and dieldrin in largemouth bass.

Two studies investigated the accumulation and reproductive effects of p,p'-dichlorodiphenyldichloroethane (DDE) and dieldrin over 30 or 120 d of oral exposure in captive Florida, USA, largemouth bass (Micropterus salmoides floridanus). The 30-d exposures were conducted during the peak reproductive season, and the 120-d study was conducted to simulate exposure throughout the ovarian cycle. Whole body chemical residue concentrations were similar, regardless of exposure duration, for the medium and high feed concentrations of either chemical; however, the low-dose residue concentrations were much lower, yet similar to natural exposures. No clear dose-response relationships were identified between chemical dose and morphological (length, weight, hepatosomatic index) or reproductive endpoints (sex steroid concentration, gonadosomatic index, percentage of fry hatching). Reproductive parameters were variable within treatment groups, indicating that circulating sex steroids and percent hatch endpoints have high natural variability among fish of the same age and reproductive stage. However, in general there was a decrease in plasma estradiol and 11-ketotestosterone for female and male fish, respectively, that were exposed to dieldrin. Overall, results suggest that exposure throughout ovarian (follicular) development to either DDE or dieldrin alone does not result in the depressed endocrine status and poor reproductive success reported in highly organochlorine pesticide-contaminated environments in Central Florida, USA.

Absorption of p,p'-dichlorodiphenyldichloroethylene and dieldrin in largemouth bass from a 60-d slow-release pellet and detection using a novel enzyme-linked immunosorbent assay method for blood plasma.

This work describes the uptake of two organochlorine pesticides from slow-release pellets by largemouth bass and the utility of a blood plasma enzyme-linked immunosorbent assay (ELISA) method for exposure verification. We measured blood and tissue levels by gas chromatography/mass spectrometry and by a novel ELISA method, and present a critical comparison of the results.

Left-right asymmetric morphogenesis in the Xenopus digestive system.

The morphogenetic mechanisms by which developing organs become left-right asymmetric entities are unknown. To investigate this issue, we compared the roles of the left and right sides of the Xenopus embryo during the development of anatomic asymmetries in the digestive system. Although both sides contribute equivalently to each of the individual digestive organs, during the initial looping of the primitive gut tube, the left side assumes concave topologies where the right side becomes convex. Of interest, the concave surfaces of the gut tube correlate with expression of the LR gene, Pitx2, and ectopic Pitx2 mRNA induces ectopic concavities in a localized manner. A morphometric comparison of the prospective concave and convex surfaces of the gut tube reveals striking disparities in their rate of elongation but no significant differences in cell proliferation. These results provide insight into the nature of symmetry-breaking morphogenetic events during left-right asymmetric organ development.