Effect of Body Weight on Echocardiographic Measurements in 19,866 Pure-Bred Cats with or without Heart Disease.

BACKGROUND: Echocardiography is a cost-efficient method to screen cats for presence of heart disease. Current reference intervals for feline cardiac dimensions do not account for body weight (BW). OBJECTIVE: To study the effect of BW on heart rate (HR), aortic (Ao), left atrial (LA) and ventricular (LV) linear dimensions in cats, and to calculate 95% prediction intervals for these variables in normal adult pure-bred cats. ANIMALS: 19 866 pure-bred cats. METHODS: Clinical data from heart screens conducted between 1999 and 2014 were included. Associations between BW, HR, and cardiac dimensions were assessed using univariate linear models and allometric scaling, including all cats, and only those considered normal, respectively. Prediction intervals were created using 95% confidence intervals obtained from regression curves. RESULTS: Associations between BW and echocardiographic dimensions were best described by allometric scaling, and all dimensions increased with increasing BW (all P<0.001). Strongest associations were found between BW and Ao, LV end diastolic, LA dimensions, and thickness of LV free wall. Weak linear associations were found between BW and HR and left atrial to aortic ratio (LA:Ao), for which HR decreased with increasing BW (P<0.001), and LA:Ao increased with increasing BW (P<0.001). Marginal differences were found for prediction formulas and prediction intervals when the dataset included all cats versus only those considered normal. CONCLUSIONS AND IMPORTANCE: BW had a clinically relevant effect on echocardiographic dimensions in cats, and BW based 95% prediction intervals may help in screening cats for heart disease.

Prostate cancer associated with CYP17 genotype.

Androgens play an important role in the development of prostate cancer. Androgen regulating genes that show allelic variation may be susceptibility factors for the disease. One of these genes, CYP17, encodes the cytochrome P450c17alpha enzyme. It catalyses steroid 17alpha-hydroxylase/17,20 lyase activities at key points in testosterone biosynthesis. We investigated the association between a polymorphism in the CYP17 gene and prostate cancer in a population-based case-control study. All individuals studied were Caucasians born in Sweden, 178 were consecutive clinical prostate cancer patients, and 160 were age-matched control individuals randomly selected from the same catchment area. DNA was extracted from blood samples. A CYP17 gene fragment was amplified by polymerase chain reaction. The MspA1I restriction enzyme, which recognizes the base pair substitution, was used to identify the allelic variants CYP17A1 and CYP17A2. Significantly more men homozygous for the CYP17A1 allele were found among prostate cancer patients compared with control individuals; odds ratio 1.61 (95% confidence interval 1.02; 2.53), P = 0.04. According to a preliminary report, the CYP17A1/A1 genotype leads to higher circulating androgen levels, possibly by encoding for a more active androgen synthesizing CYP17 enzyme. Consequently, the CYP17A1/A1 genotype, which was found in a higher frequency among prostate cancer patients, may prove to be one of the important susceptibility factors for prostate cancer. If verified, this genotype is likely to convey a larger risk on a population basis, than the rare hereditary prostate cancer genes do.