PULMONARY HYPERTENSION IN DOGS WITH MITRAL REGURGITATION ATTRIBUTABLE TO MYXOMATOUS VALVE DISEASE

Pulmonary hypertension has been associated with mitral insufficiency caused by chronic degenerative valve disease in dogs. Our aim was to search for associations between left atrial to aortic root ratio, end‐systolic and end‐diastolic volume indices, and changes in the right ventricular to right atrial pressure gradient as estimated by the peak velocity of tricuspid regurgitation in dogs with chronic degenerative valve disease and different classes of heart failure. Dogs, for which follow‐up was available were evaluated for changes in the right ventricular to right atrial systolic pressure gradient over time. Three hundred and forty‐four dogs were studied; 51 in the International Small Animal Cardiac Health Council class 1a, 75 in class 1b, 113 in class 2, 97 in class 3a, and 8 in class 3b. The mean values for right ventricular to right atrial systolic pressure gradient, end‐systolic volume index, end‐diastolic volume index, and left atrial to aortic ratio were 49.2 ± 17.1 mmHg, 149.12 ± 60.8 and 37.7 ± 21.6 ml/m², and 1.9 ± 0.5, respectively. A weak positive correlation was found between the right ventricular to right atrial systolic pressure gradient and the left atrial to aorta ratio (r=0.242, P<0.0001), end‐diastolic volume index (r=0.242, P<0.0001), and end‐systolic volume index (r=0.129, P<0.001). Follow up was available for 49 dogs. Of these, 18 had an increased, 12 a decreased, and 19 a stable right ventricular to right atrial systolic pressure gradient despite therapy. The equivalence point between the sensitivity and specificity curves of about 80% in the coincident point corresponded to a right ventricular to right atrial systolic pressure gradient of 48 mmHg. Our results suggest an association between the progressive nature of chronic degenerative mitral valve disease and pulmonary hypertension. It is of clinical interest that, with a right ventricular to right atrial systolic pressure gradient pressure gradient at or above 48 mmHg, pulmonary hypertension does not appear to improve despite therapy targeted at lowering the left atrial load.     

传染性海绵状脑病的一种特征性标识

传染性海绵状脑病 ( TSE)包括牛传染性海绵状脑病 ( BSE) ,鹿和麋鹿的慢性消耗性疾病( CWD) ,人的克雅氏病 ( CJD)和新型—变异型克雅氏病 ( nv CJD)等。该类疾病致病性主要表现在中枢神经系统 ( CNS) ,共同特点包括空泡形成、神经肌质增生、抗蛋白酶的非正常折叠同形物( prpsc)聚集、神经细胞死亡。目前尚无有效的早期诊断和治疗措施。我们发现了一种容易在组织中简便检测的分子标识物 ,即针对红细胞系特异的转录本表达水平急剧降低是 TSE的一个共同特点。发现了在 TSE致病机理中红细胞系的介导作用。此发现对该病的诊断和治疗研…