Myocarditis in round heart disease of turkeys

Summary Round heart disease in the turkey has been studied by light and electron microscopy. Myocarditis, characterized by focal muscle cell degeneration and mononuclear infiltrates, was present in turkeys from 1 day after hatching through 8 weeks of age. Myocardial injury was most severe from age 5 to 12 days. Virus-like particles, 60–90 mµ in diameter, resembling the avian leukosis viruses, were present in the myocardial cells of all turkeys with myocarditis.Dilatation and hypertrophy, predominantly of the left ventricle developed after the second week of life. Collagen accumulation beneath the endocardium was evident by electron microscopy in 1- and 2-day-old birds. This progressed to marked endocardial fibroelastosis after 1 month and was often associated with involvement of the mitral valve and its papillary muscles and chordae tendineae. Maturing and adult turkeys demonstrated congestive heart failure with congestion of the lungs and liver, pleural effusions and ascites. Because of the similarity of gross and microscopic findings, round heart disease in turkeys may serve as an experimental model for primary endocardial fibroelastosis in humans.Supported by research grants from the Dwan Family Fund; University of Minnesota Graduate School; Minnesota Turkey Growers Association; U.S. Public Health Service, National Heart Institute, HE06314-10, HE05694 and Training Grant HE05570.     

Indications and diagnostic outcome of antineutrophil cytoplasmic antibody testing in hospital medicine: a pattern of over-screening

Clinical Rheumatology - Antineutrophil cytoplasmic antibodies (ANCA) serology can aid in the diagnosis and classification of ANCA-associated vasculitides (AAV). However, it is often ordered in...     

Alteration by immunosuppression of early mortality in a naturally occurring cardiomyopathy.

Turkeys from a highly inbred flock, which shows a 100 per cent incidence of naturally occurring cardiomyopathy, were treated daily for 3 weeks following hatching with cortisone acetate, or for 4 days following hatching with parenteral cyclophosphamide, or underwent surgical removal of the bursa of Fabricius at hatching. Mortality was significantly reduced during the first 10 days of age when each of the treated groups was compared with its own control group. By 5 weeks of age, the mortality rates in the bursectomized and cyclophosphamide-treated birds were not significantly different than their control groups. Five-week mortality in the cortisone acetate-treated group, however, was significantly lower than in its control group. Long-term morbidity, as reflected by the incidence of cardiac dilatation and hypertrophy in all birds during or killed through one year of age, was lower in the cortisone acetate-treated birds and significantly reduced in the bursectomized birds. These data suggest that the humoral immune system may function in the pathogenesis of this naturally occurring cardiomyopathy in the turkey.     

Paradoxes of the EphB4 receptor in cancer

Recent findings have started to uncover the intriguing roles of the Eph family of receptor tyrosine kinases in normal epithelial cells and during oncogenic transformation. This review focuses on EphB4, an Eph receptor that has both tumor-suppressing and tumor-promoting activities in breast cancer. Understanding the multifaceted role of EphB4 in tumorigenesis may allow the development of new anticancer therapies.     

Ki-67 expression in primary breast carcinomas and their axillary lymph node metastases: clinical implications

Proliferative activity of tumour cells assessed by immunohistochemical Ki-67 expression is one of several prognostic indicators in breast cancer. The major objective of this study was to investigate the prognostic impact of Ki-67 proliferative activity in the axillary lymph node metastases and in the matched primary breast carcinoma from 194 patients. There was a statistically significant up-regulation of Ki-67 protein in the metastatic deposit compared to where the primary tumour was found (p = 0.001). A low Ki-67 index in both the primary and the metastatic tumours was a favorable prognostic factor. A high index in both primary and metastatic lesion and an up-regulation from a low index in the primary tumour to a high index in the metastatic deposit represented an unfavorable prognostic factor. Multivariate analysis showed that Ki-67 expression in the metastases was a superior independent prognostic factor of clinical outcomes compared to that in the primary tumours. Ki-67 expression in ≥10% of carcinoma cells in the primary tumours and ≥15% in the nodal metastases seems to be optimal cut-off levels. Ki-67 is of value as an independent prognostic factor in breast cancer.     

Reduced lipid peroxidation in dilated hearts of cardiomyopathic turkeys

Adverse pulmonary reactions to some nitrofuran antibiotics are thought, in part, to involve production of reactive oxygen radicals. Furazolidone, a nitrofuran antibiotic, causes a dilated cardiomyopathy in domestic turkeys. The mechanism of this drug induced cardiomyopathy is unknown. We investigated the possible role of free radical injury in this heart failure model. Left ventricular lipid peroxidation capacity, assessed by two methods (the thiobarbituric acid reactive substances and lipid hydroperoxides assays respectively), was investigated in five 5-8 week old cardiomyopathic turkeys with severe cardiac dilatation, left ventricular dysfunction and systemic hypotension, and in five control birds. Superoxide dismutase activity, total and manganese, was also measured in the crude left ventricular homogenates. Both lipid peroxidation products were reduced in the myopathic hearts: thiobarbituric acid reactive substances (malondialdehyde) 70(SEM 4) v 86(3) nmol.100 mg protein-1 in controls, p less than 0.02; and lipid hydroperoxides 29(7) v 74(14) nmol.100 mg protein-1, p less than 0.02. Total superoxide dismutase activity was similar in cardiomyopathic and control hearts: 670(26) v 657(105) nitrite units.100 mg protein-1. Although total superoxide dismutase activity was unchanged, we found decreased manganese superoxide dismutase in the dilated hearts compared with controls (54% v 84% of total activity, p less than 0.02). In separate in vitro experiments furazolidone (2-10 mg.g wet weight-1) did not increase malondialdehyde production in turkey (or rat) left ventricular homogenates. These results indicate that cardiomyopathy induced by furazolidone is associated with decreased myocardial lipid peroxidation. Although as yet unexplained, the decrease may be due to a diminished amount of heart lipid susceptible to peroxidation accompanying the process of cardiac hypertrophy and dilatation.(ABSTRACT TRUNCATED AT 250 WORDS)