Evaluation of QT interval prolongation in dogs with heart failure.

Comparison of the QT interval and corrected QT interval values that were calculated by the methods of Bazett (QTc1) and Fridericia (QTc2) were made between dogs with or without cardiac diseases to determine the influence of the QT interval on canine heart failure. Upon comparison of the measured values on ECG between the cardiac disease and non-cardiac disease groups, it was observed that the heart rate(HR) was significantly higher in the cardiac disease group than in the non-cardiac disease group, although the QT interval was similar in the two groups. The QTc1 and QTc2 were significantly longer in the cardiac disease group than in the non-cardiac disease group. With the progression of the New York Heart Association Class, the HR tended to increase. The QTc1 and QTc2 became significantly prolonged with the progression of heart failure. Nevertheless, because Bazett's correction formula is known to overcorrect when the HR is high, it was considered that the QTc1 was actually overcorrected by high HR with the progression of heart failure. The QTc2, on the other hand, was only slightly influenced by HR, suggesting that the prolongation was due to the progression of heart failure. These results suggest that the prolongation of QTc2 in cardiac disease reflects the substantial prolongation of the QT interval without the influence of HR. It is suggested that the QTc2 could be a useful parameter for assessing the degree of heart failure in dogs with cardiac disease.

A comparative analysis of human papillomavirus types 16 and 18 and expression of p53 gene and Ki-67 in cervical, vaginal, and vulvar carcinomas.

UNLABELLED: This study aimed to investigate the correlation between HPV positivity, p53 overexpression, and cell proliferative activity in cervical, vaginal, and vulvar squamous cell carcinoma. METHODS: Sixteen vaginal and 31 vulvar squamous cell carcinomas were examined retrospectively for overexpression of p53 gene and Ki67 antigen by immunohistochemistry and for the presence of HPV types 16 and 18 DNA using a polymerase chain reaction (PCR) method. The results were compared with those obtained from 40 cervical squamous cell carcinomas. RESULTS: HPV type 16 or 18 DNA was detected in 21 (52.8%) of 40 cases of cervical carcinomas and p53 overexpression in one (2.5%), while HPV DNA sequences were detected in seven (43.7%) of 16 cases of vaginal carcinoma and p53 overexpression in three (18.7%). With regard to vulvar carcinoma, HPV was harbored in four (12.8%) of 31 cases and p53 overexpression in 19 (61.2%). These results indicated statistically significant inverse correlations between HPV positivity and p53 overexpression (R = -0.999, P < 0.0001). Overexpression of Ki-67 was detected in 28 (70.0%) of 40, 12 (75.0%) of 16, and 21 (67.7%) of 31, cervical, vaginal, and vulvar carcinomas, respectively. There was no significant difference among the three groups. CONCLUSIONS: In cervical carcinoma, HPV types 16 and 18 might play a common causal role, and in vulvar carcinoma, p53 gene mutations might be a main causal factor for carcinogenesis. Vaginal carcinoma, on the other hand, is considered to have transitional characteristics between cervical and vulvar carcinoma.