Lipogranulomas and pigment granulomas in livers of dogs with portosystemic shunt.

Lipogranulomas are lesions found in histopathological liver examination in humans and in various animal species, including dogs, especially those with portosystemic shunts. They consist of macrophages and other inflammatory cells, and sometimes they contain iron salts (pigment granuloma). This study aimed at determining the number of granulomas and cellular composition of lipogranulomas in dogs with the congenital extrahepatic portosystemic shunt, and to identify factors associated with their development. 44 archival liver samples from dogs with portosystemic shunt were stained using HE, Perl's method and - in randomly-selected cases - immunohistochemically against CD56, CD20 and CD3 (DAKO). A reduction in the size of the liver was observed in all dogs during laparotomy, and the diameter of the vessel circumventing the liver was also measured (in 24 dogs). Lipogranulomas were found in 52.3% of samples; iron salts were present in 47.8% of them; 72% of cells in lipogranulomas were macrophages. In lipogranulomas both types of lymphocytes - T and B - were seen. The presence of lipogranulomas in liver samples in dogs was connected with fatty degeneration of hepatocytes and was correlated with the age of animals and with the diameter of the abnormal vessel circumventing the liver. Their formation appears to be triggered by severe ischemia and shortage of nutrient supply.

The application of circulating tumor cells detecting methods in veterinary oncology.

Cancers are one of the most common diseases affecting dogs. Many of them develop spontaneously and their biology and histopathology shows many similarities to human cancers. What more, it is proved that there are much more analogies in molecular mechanisms of cancer development between these two species. Human oncology is seeking more and more efficient methods for an early disease detection which results directly in the extended life expectancy of patients affected. One of the most modern trends in the diagnosis of cancer is to detect circulating tumor cells (CTC) in the blood of patients. It is known that these cells are responsible for the formation of metastases in distant organs what results in the patient death. Moreover, it's confirmed that CTC are already present in patients' bloodstream in the early stages of tumor development. There is no doubt that mechanism of metastasis development in dogs is identical and thus the CTC are also present in their bloodstream. Despite the intense researches there is still no optimal method of isolating cancer cells from the blood where they occur extremely rarely. The purpose of this study is to analyze the implications of the detection methods of tumor cells in the blood in veterinary oncology.

Modulation of specific biochemical blood parameters by helminth infection in laboratory Beagle dogs.

The objective of this study was to examine the independent effect of helminths infection on biochemical blood parameters in Beagles intended for laboratory use which may contribute to a change of experimental results. As a result of research, the authors confirmed the negative effect of helminth invasion on the metabolism of the liver and kidney in laboratory dogs. Stool samples from thirty Beagle puppies were examined for parasites before the puppies were moved to the animal facility, and all were dewormed with Vetminth paste on the day they were moved. Stool examination was performed three more times and animals were given Drontal Plus flavor (Bayer) and Baycox 5% (Bayer). A fourth parasitological examination revealed no intestinal parasites in the feces. Three blood biochemical tests were performed. Experimental results clearly indicate the significant impact of intestinal parasites in dogs used in experiments.

Differences in antiapoptotic, proliferative activities and morphometry in dilated and ischemic cardiomyopathy: study of hearts explanted from transplant recipients.

BACKGROUND: Antiapoptotic as well as replacement and proliferative mechanisms take place in the myocardium in dilated cardiomyopathy (DCM) and ischemic heart disease (IHD). We sought to estimate antiapoptotic, proliferative and replacement activities in cardiomyopathies. MATERIALS: The study groups included seven hearts with DCM and eight with IHD, which had been explanted at the time of transplantation. The comparator group consisted of cases of myocardial hypertrophy and the control group, donor fragments. METHODS: Antiapoptotic and proliferative responses were determined immunohistochemically as Bcl-2 and Ki67 expression by semiquantitative assessment of the intensity of staining. We also measured and statistically analyzed the integrative morphometric measurements of the fraction of fibrosis area, the nucleosarcoplasmic ratio, and cardiocyte diameter. RESULTS: No Bcl-2 expression was observed in the controls. The strongest reaction was seen in the DCM group, then in the IHD, and in the comparator group of myocardial hypertrophy. Proliferative activity was seen only in endocardial and interstitial fibroblasts in DCM and IHD cases. The cardiocyte diameter showed no statistical association between myocardial hypertrophy and IHD, or IHD and DCM, whereas the nucleosarcoplasmic ratios were significantly different from control groups for all comparisons. Myocardial fibrosis showed the highest values in DCM and IHD. Discriminant analysis showed the value of interstitial fibrosis and cardiocyte diameter to categorize the analyzed groups. CONCLUSIONS: Antiapoptotic Bcl-2 activity seemed to play an important role in cardiocyte preservation, while proliferative activity was resticted to interstitial connective tissue cells as a replacement process. Myocardial Bcl-2 expression, the extent of myocardial fibrosis, and cardiocyte diameter may serve as additional diagnostic tools to differentiate cardiomyopathies.

Pivotal karyometric measurements in different types of cardiomyopathic morphology: study of hearts explanted from transplant recipients.

BACKGROUND: Morphometric studies based on the measurement of cardiocyte nuclei have focused on progressive hypertrophy rather than shape, which is a deciding factor for the diagnosis of hypertrophy in myocardial diseases. The aim of this research was to demonstrate how the digital morphology of cardiocyte nuclei change correlated with the type of myocardial pathology. MATERIALS AND METHODS: The study groups encompassed 7 hearts with dilated cardiomyopathy (DCM) and 8 hearts with ischemic heart disease (IHD) which were explanted. A comparative group consisting of myocardial hypertrophy was contrasted with a control group of donor heart fragments. Cardiocyte nuclei were evaluated morphometrically on histologic slides. We calculated the nuclear area, length, breadth, perimeter, roundness, elongation, fullness factors, and nuclear chromatin mean gray level. The results were subjected to discriminant analysis. RESULTS: All karyometric measurements analyzed by backward discriminant analysis showed only 2 powerful factors: nuclear breadth and chromatin mean gray level. The Mahalanobis distance showed the proximity of control and hypertrophy groups, whereas differences between IHD and DCM were nonsignificant. CONCLUSION: The lack of karyometric differences between IHD and DCM suggested a common morphologic response for long-lasting progressive injury. The main morphologic differences were dependent on nuclear chromatin activity/stainability and nuclear breadth, suggesting darker and thinned nuclei in normal and adaptative stages and irregular brighter nuclei in cardiomyopathies.