An exploratory study of competition scores and salivary cortisol concentrations in Warmblood horses.

The main objective of this explorative study was to describe the relationship between competition scores and salivary cortisol concentrations in young horses during dressage and showjumping competitions. The study also investigated whether the diurnal rhythm of salivary cortisol concentrations was affected by competition over consecutive days compared with the home environment. Saliva samples were collected from 126 dressage horses and showjumpers in their home environment and at 3 different events. The relationship between scores given by judges at the competition and cortisol concentrations at the event was assessed. The results demonstrated that competition scores correlated positively to baseline cortisol concentrations at one of 3 events (r = 0.53, P < 0.001). Salivary cortisol concentrations followed a diurnal rhythm with the highest concentrations measured in the morning and the lowest in the evening, both at home and in the competition environment (P < 0.05). Salivary cortisol concentrations were greater during the competitions than at home (P < 0.05) except at one event where showjumpers did not increase between home and competition. Dressage horses had the highest baseline cortisol concentrations at competition, and exercise caused cortisol concentrations to increase in both showjumpers and dressage horses (P < 0.001). In conclusion, the diurnal rhythm in salivary cortisol concentrations was maintained in the novel environment. Dressage horses demonstrated greater baseline cortisol concentrations at competition than showjumpers, suggesting that they may perceive the novel environment as more stressful. Furthermore, there was no consistent relationship between baseline salivary cortisol concentrations and competition scores across the events.

Adverse outcome analyses of observational data: assessing cardiovascular risk in HIV disease.

Clinical decisions are ideally based on randomized trials but must often rely on observational data analyses, which are less straightforward and more influenced by methodology. The authors, from a series of expert roundtables convened by the Forum for Collaborative HIV Research on the use of observational studies to assess cardiovascular disease risk in human immunodeficiency virus infection, recommend that clinicians who review or interpret epidemiological publications consider 7 key statistical issues: (1) clear explanation of confounding and adjustment; (2) handling and impact of missing data; (3) consistency and clinical relevance of outcome measurements and covariate risk factors; (4) multivariate modeling techniques including time-dependent variables; (5) how multiple testing is addressed; (6) distinction between statistical and clinical significance; and (7) need for confirmation from independent databases. Recommendations to permit better understanding of potential methodological limitations include both responsible public access to de-identified source data, where permitted, and exploration of novel statistical methods.

Laminin alpha2 muscular dystrophy: genotype/phenotype studies of 22 patients.

OBJECTIVE: To determine the number of primary laminin alpha2 gene mutations and to conduct genotype/phenotype correlation in a cohort of laminin alpha2-deficient congenital muscular dystrophy patients. BACKGROUND: Congenital muscular dystrophies (CMD) are a heterogeneous group of muscle disorders characterized by early onset muscular dystrophy and a variable involvement of the CNS. Laminin alpha2 deficiency has been reported in about 40 to 50% of cases of the occidental, classic type of CMD. Laminin alpha2 is a muscle specific isoform of laminin localized to the basal lamina of muscle fibers, where it is thought to interact with myofiber membrane receptor, such as integrins, and possibly dystrophin-associated glycoproteins. METHODS: Seventy-five CMD patients were tested for laminin alpha2 expression by immunofluorescence and immunoblot. The entire 10 kb laminin alpha2 coding sequence of 22 completely laminin alpha2-deficient patients was screened for causative mutations by reverse transcription (RT)-PCR/single strand conformational polymorphisms (SSCP) analysis and protein truncation test (PTT) analysis followed by automatic sequencing of patient cDNA. Clinical data from the laminin alpha2-deficient patients were collected. RESULTS: Thirty laminin alpha2-negative patients were identified (40% of CMD patients tested) and 22 of them were screened for laminin alpha2 mutations. Clinical features of laminin alpha2-deficient patients were similar, with severe floppiness at birth, delay in achievement of motor milestones, and MRI findings of white matter changes with normal intelligence. Loss-of-function mutations were identified in 95% (21/22) of the patients studied. SSCP analysis detected laminin alpha2 gene mutations in about 50% of the mutant chromosomes; PTT successfully identified 75% of the mutations. A two base pair deletion mutation at position 2,096-2,097 bp was present in 23% of the patients analyzed. CONCLUSIONS: Our data suggest that the large majority of laminin alpha2-deficient patients show laminin alpha2 gene mutations.

2-year carcinogenicity study in the male NMRI mouse with 2-ethylhexyl acrylate by epicutaneous administration.

A 2 yr carcinogenicity study of 2-ethylhexyl acrylate (2-EHA) was conducted by applying 25 microliters 21.5, 43 or 85% 2-EHA or 0.015% benzo[a]pyrene (B[a]P) in acetone, three times/wk, to the clipped dorsal skin of male NMRI mice (80 per group). A further group received acetone and served as the vehicle control. After about 7 months of treatment, half of each group was rested from treatment for a period of 2 months, then treated with the promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) for 20 wk followed by observation until termination of the study. The other half of each group received continuous treatment with 2-EHA, B[a]P or acetone, respectively, for 2 yr. Signs signs of skin irritation were apparent in all groups treated with 2-EHA [hyperkeratosis, hyperplasia (acanthosis), crust formation and ulceration]. In the group treated with B[a]P alone or B[a]P with TPA, 79% and 67% of the mice, respectively, bore squamous cell carcinomas. None of the mice treated with acetone or 2-EHA alone developed a skin tumour at the application site. One squamous cell papilloma occurred in each of the groups treated with 2-EHA and TPA, an incidence matched by the single squamous cell papilloma in an untreated area of an acetone control mouse. Thus, 2-EHA proved not to be carcinogenic in the skin of male NMRI mice by epicutaneous administration.

Effects of bis(tri-n-butyltin)oxide in Japanese quail exposed during egg laying period: an interlaboratory comparison study.

The guideline no. 206 for testing of chemicals of the Organization for Economic Cooperation and Development (OECD) comprising an avian reproduction test using the Japanese quail (Coturnix coturnix japonica; Termminck and Schlegel 1849) as pair-hold test organisms has been applied in a version that reduced the treatment period to 6 weeks without any pretreatment. In the present study bis(tri-n-butyltin)oxide, C.A. No. 56-35-9 (tributyltin oxide, TBTO) was examined by five participants in an interlaboratory comparison test. A comparable regimen of dosing was performed by all participants starting either with 24 or 60 mg/kg TBTO in the feed and ending with 150 or 375 mg/kg. Within this dose range no signs of toxicity in adults were observed. Substance-related effects however were obvious with regard to egg production, fertility, hatching success, and survival of 14 day-old chicks. A clear dose dependency was given regarding effects on egg weight and on hatchability. The no-observed-effect concentrations for these two parameters was 60 mg/kg TBTO, characterizing these parameters as the most sensitive in this investigation. With the presented set of test parameters further aspects of subchronic toxicity in adults and chicks can be assessed as well as the validity of the performed test. Comparing the results for most test parameters consistency is obvious, thus confirming the applicability of the presented test guideline.

Percutaneous computed tomography stabilization of moderate to severe slipped capital femoral epiphysis.

A percutaneous computed tomography (CT) guided pinning of experimentally reproduced slipped capital femoral epiphysis in five cadavers and one patient--who had bilateral pinning for moderate and severe grade chronic slip--was conducted. Prior investigations of cadavers revealed that this procedure can be performed in selected cases. The details of the technique are illustrated in this article.

Effect of 3,4-dichloroaniline on the early life stages of the zebrafish (Brachydanio rerio): results of a comparative laboratory study.

An early life-stage (ELS) test was conducted with the zebrafish and 3,4-dichloroaniline (3,4-DCA) in eight laboratories. Based on the results from all eight laboratories, an LOEC of 200 micrograms 3,4-dichloroaniline/liter applies for the early life stages of the zebrafish. Effects observed were reduction of the survival rate and malformations. If the 100 micrograms/liter concentration additionally tested by one laboratory is included in the assessment, an LOEC of 100 micrograms 3,4-DCA/liter is obtained for the survival rate and increase in length. The NOEC is 20 micrograms/liter. The present results of a comparative laboratory study with the zebrafish show that a 42-day ELS test can be conducted with this species of fish, and affords meaningful results.

Study of possible teratogenic effects of the fungicide maneb on chick embryos.

The teratogenicity of the fungicide maneb (80% active ingredient and 20% inert ingredients) in chick embryos was evaluated. Eggs, before incubation, were dipped in 0.2% or 1.2% aqueous dispersions of maneb for 30 seconds. An untreated group, a water group and a formulation ingredient group, at the concentration present in the 1.2% maneb group, ensured control in the study. Eggs were incubated for 18 days then transferred to hatching racks and allowed to hatch normally. Viable chicks and chicks "dead in shell" were assessed for external deformities. There was no evidence that maneb or its formulation ingredients were teratogenic or embryotoxic to developing chick embryos.