Authors:Ágnes Sterczer, Tibor Németh, Míra Mándoki, Péter Gálfi, and Csaba Jakab
The authors describe a case of synchronously occurring (double) tumours, i.e. primary hepatocellular carcinoma and aortic body chemodectoma in a 14-year-old mixed-breed male dog. The tumours were identified during necropsy, following euthanasia. In the last months of its life, the dog showed signs of weakness, anorexia, apathy, inactivity, and abdominal palpation elicited a painful reaction. The primary liver cancer emerged in the left lateral lobe without evidence of any distant metastases. Histopathological and immunohistochemical investigations revealed a well-differentiated, trabecular, claudin-7-, claudin-5- and pancytokeratin-negative hepatocellular carcinoma. The Ki-67 proliferation index was 33%. During necropsy, a synchronously occurring benign, grade I type aortic body chemodectoma was also detected in the dog. This neuroendocrine tumour showed chromogranin-, synaptophysin-, neuron-specific enolase- and S100 protein-positivity, and the Ki-67 proliferation index was 2%. The authors believe that this is the first description of synchronously occurring hepatocellular carcinoma and aortic body chemodectoma in a dog.
Authors:Csaba Jakab, Miklós Rusvai, Péter Gálfi, Judit Halász, and Janina Kulka
Claudin-5 is an endothelium-specific tight junction protein. The aim of the present study was to detect the expression pattern of this molecule in intact pancreatic tissues and in well-differentiated and poorly differentiated pancreatic acinar cell carcinomas from dogs by the use of cross-reactive humanised anticlaudin-5 antibody. The necropsy samples taken from dogs included 10 nonneoplastic pancreatic tissues, 10 well-differentiated pancreatic acinar cell carcinomas, 10 poorly differentiated pancreatic acinar cell carcinomas, 5 intrahepatic metastases of well-differentiated and 5 intrahepatic metastases of poorly differentiated acinar cell carcinomas. A strong lateral membrane claudin-5 positivity was detected in exocrine cells in all intact pancreas samples. The endocrine cells of the islets of Langerhans and the epithelial cells of the ducts were negative for claudin-5. The endothelial cells of vessels and lymphatic channels in the stroma of the intact pancreas showed strong membrane positivity for this claudin. All well-differentiated exocrine pancreas carcinomas and all poorly-differentiated pancreatic acinar cell carcinoma samples showed a diffuse loss of claudin-5 expression. The claudin-5-positive peritumoural vessels and lymphatic channels facilitated the detection of vascular invasion of the claudin-5-negative cancer cells. In liver metastasis samples, the pancreatic carcinomas were negative for claudin-5. It seems that the loss of expression of claudin-5 may lead to carcinogenesis in canine exocrine pancreatic cells.
Authors:Ákos Jerzsele, Béla Gyetvai, István Csere, and Péter Gálfi
Malassezia pachydermatis is a commonly isolated yeast in veterinary dermatology that can produce biofilms in vitro and in vivo, lowering its susceptibility to antimicrobial drugs. The aim of this study was to determine and compare the in vitro susceptibility of planktonic cells and biofilms of M. pachydermatis isolates to ketoconazole and itraconazole. The presence of biofilm formation was confirmed by crystal violet staining and absorbance measurement at 595 nm wavelength, and by a scanning electron microscopy method. Cell viability was determined by the Celltiter 96 Aqueous One solution assay containing a water-soluble tetrazolium compound (MTS) with absorbance measurement at 490 nm. Planktonic cell minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of ketoconazole and itraconazole were very low: MIC90 and MFC90 were 0.032 and 0.125 μg/ml for ketoconazole, while 0.063 and 0.25 μg/ml for itraconazole, respectively. Also, the half maximal effective concentrations (EC50) of itraconazole were higher for planktonic cells and biofilms compared to ketoconazole. The EC50 values of ketoconazole were 18–169 times higher and those of itraconazole 13–124 times higher for biofilms than for planktonic cells. Biofilm EC50 levels exceeded MICs 103–2060 times for ketoconazole and 84–1400 times for itraconazole. No significant difference was found between these values of the two substances. In conclusion, biofilms of all examined M. pachydermatis strains were much less susceptible to ketoconazole and itraconazole than their planktonic forms.
Authors:Csaba Jakab, Miklós Rusvai, Nóra Biró, Zoltán Szabó, Péter Gálfi, and Janina Kulka
A 5-year-old female degu (
) showed the clinical sign of metrorrhagia. During ovariohysterectomy a circumscribed tumoural lesion was found in the right uterine horn. The histopathological diagnosis of this soft tissue mass was primary benign cavernous angioleiomyoma of the uterus. During immunohistochemical analysis the neoplastic endothelial cells of this mixed mesenchymal tumour showed strong membrane positivity for the endothelial marker claudin-5 but were negative for CD31 (another endothelial marker). The endothelial cells of the internal positive control tissues such as intact peritumoural vessels were positive for claudin-5 but negative for the CD31 endothelial marker. As it has been described also in other species, it seems that claudin-5 is a better endothelial marker than CD31 for the detection of normal and neoplastic endothelial cells in different tissues of degus.
Authors:Csaba Jakab, Miklós Rusvai, Péter Gálfi, Ágnes Szabára, Zoltán Szabó, and Janina Kulka
Claudins are key tight junctional proteins between adjacent epithelial, mesothelial or endothelial cells, which are responsible for the permeability of the paracellular space. This paper describes that the endothelial cells of normal hepatic arterioles, portal venules and portal lymphatics as well as the endothelium of sinusoids from dogs show strong membranous claudin-5 cross-reactivity. In 25 liver biopsy samples taken from dogs with portal vein hypoperfusion, an increased number of arterioles was detected in the portal areas (PAs) by the use of humanised anti-claudin-5 antibody. The increased number of hyperplastic hepatic arterioles per PA was 5–6, 8–12 and 15–20 in the case of small, medium-sized and large PAs, respectively. It is suggested that the claudin-5 marker can improve the detection of hepatic arteriolar proliferation in the PAs of liver samples.
Authors:Csaba Jakab, Miklós Rusvai, Zoltán Szabó, Péter Gálfi, Miklós Marosán, Janina Kulka, and János Gál
In this study, synchronous spontaneous, independent liver and gallbladder tumours were detected in a Bearded dragon (Pogona vitticeps). The multiple tumours consisted of intrahepatic cholangiocarcinoma as well as in situ adenocarcinoma and two adenomas of the gallbladder. The biliary epithelial cells and the cholangiocarcinoma showed membranous cross-immunoreactivity for claudin-7. The gallbladder epithelial cells, its adenoma and adenocarcinoma showed basolateral cross-reactivity for claudin-7. We think that the humanised anti-claudin-7 antibody is a good marker for the detection of different primary cholangiocellular and gallbladder tumours in Bearded dragons. The cholangiocytes, the cholangiocarcinoma, the endothelial cells of the liver and the epithelial cells and gallbladder tumours all showed claudin-5 cross-reactivity. The humanised anti-cytokeratin AE1–AE3 antibody showed cross-reactivity in the biliary epithelial cells, cholangiocarcinoma cells, epithelial cells and tumour cells of the gallbladder. It seems that this humanised antibody is a useful epithelial marker for the different neoplastic lesions of epithelial cells in reptiles. The humanised anti-α-smooth muscle actin (α-SMA) antibody showed intense cross-reactivity in the smooth muscle cells of the hepatic vessels and in the muscle layer of the gallbladder. The portal myofibroblasts, the endothelial cells of the sinusoids and the stromal cells of the cholangiocarcinoma and gallbladder tumours were positive for α-SMA. The antibovine anti-vimentin and humanised anti-Ki-67 antibodies did not show crossreactivity in the different samples from the Bearded dragon.
Authors:Csaba Jakab, Attila Szász, Janina Kulka, Ferenc Baska, Miklós Rusvai, Péter Gálfi, and Tibor Németh
This short report describes a case of tricuspid valvular metastasis of canine disseminated histiocytic sarcoma in a 9-year-old female Rottweiler. Immunohistochemically the malignant neoplastic cells gave a strong reaction for vimentin and lysozyme, and showed negativity for serotonin, CD3, CD79a and cytokeratin. The intratumoural microvessels were detected by immunohistochemistry using CD31 and claudin-5. This appears to be the first report of a valvular metastasis of canine malignant histiocytosis.
Authors:Csaba Jakab, Attila Szász, Janina Kulka, Zsuzsa Schaff, Miklós Rusvai, Tibor Németh, and Péter Gálfi
This report describes a case of a canine cutaneous grade I mast cell tumour which developed within a lipoma in the right axillar region of an 8-year-old male Boxer. Immunohistologically, the neoplastic mast cells were positive for serotonin, CD45 vimentin and p53, and negative for lysozyme, CD3 and CD79a expression. The proliferation index of the mast cell tumour based on the Ki-67 antigen was 6.1%. Between the benign neoplastic lipocytes and mastocytoma tumour cells intratumoural microvessels were detected by immunohistochemical staining using CD31 and claudin-5 as markers for vascular endothelium.
Authors:Béla Gyetvai, Ákos Jerzsele, Erzsébet Pászti-Gere, Gábor Nagy, and Péter Gálfi
Gentamicin is an aminoglycoside antibiotic widely used in combination with dimethyl sulphoxide (DMSO) in topical drug formulations. It is not known, however, whether DMSO can enhance the permeation of gentamicin through biological membranes, leading to oto- and nephrotoxic side effects. A simple and reliable high-performance liquid chromatographic (HPLC) method was applied for the quantitative determination of gentamicin collected from the apical and basolateral compartments of the porcine intestinal epithelial cell line IPEC-J2 cell monolayer using fluorometric derivatisation of the analyte with fluorenylmethyloxycarbonyl chloride (FMOC) prior to chromatographic run in the presence and absence of 1% DMSO. The lack of change in transepithelial electrical resistance (TER) demonstrated that gentamicin and 1% DMSO did not affect IPEC-J2 cell monolayer integrity via the disruption of cell membranes. Chromatographic data also ascertained that gentamicin penetration across the cell monolayer even in the presence of 1% DMSO was negligible at 6 h after the beginning of apical gentamicin administration. This study further indicates that the addition of this organic solvent does not increase the incidence of toxic effects related to gentamicin permeation.
Authors:Csaba Jakab, Judit Halász, Attila Szász, Enkhjargal Batmunkh, András Kiss, Zsuzsa Schaff, Miklós Rusvai, Péter Gálfi, and Janina Kulka
The recently identified claudins are dominant components of tight junctions, responsible for cell adhesion, polarity and paracellular permeability. Certain claudins have been shown to have relevance in tumour development. The aim of the present study was to analyse the expression of claudin-1,-2,-3,-4,-5,-7 and-10 in normal canine mammary glands. Samples from the inguinal mammary regions of 20 non-castrated, 1–13 years old female dogs were studied. Immunohistochemical analysis was performed on conventional specimens and tissue microarrays. The results of the immunohistochemical reactions detecting claudins in tissue sections were photodocumented. The immunoreactivity of claudins was quantitatively analysed on digital images using Leica QWin morphometry software. Intense membranous immunolabelling was found for claudin-1,-3 and-7, intense membranous with non-granular cytoplasmic immunolabelling for claudin-2, moderate membranous immunolabelling for claudin-4 and-5, and weak membranous immunolabelling for claudin-10. The occurrence of tight junctions was confirmed by ultrathin section electron microscopy. The available data suggested that claudins might be proteins preserved throughout the evolution of mammals. The results of our study support the concept that they are indeed preserved, since the same type of claudins, in identical distribution, could be detected in our canine mammary tissue samples as could be found in human mammary tissue.