Mahmut Sözmen

Use of Fine Needle Aspirates and Flow Cytometry for the Diagnosis, Classification, and Immunophenotyping of Canine Lymphomas:

Fifty canine lymphomas were classified cytomorphologically using the updated Kiel classification scheme. Aspirates of lymph nodes from dogs with lymphoma were stained using 5 canine-specific antibodies and 3 human-specific antibodies that cross-react with canine lymphocytes. The antibody-stained aspirates were analyzed by flow cytometry. A total of 32 (64%) of the 50 lymphomas were characterized as B-cell origin and 18 (36%) were of T-cell origin. B-cell lymphomas were identified in 12 females and 20 males with a mean age of 8.35 years. T-cell lymphomas were identified in 8 females and 10 males with a mean age of 7.9 years. A minority of the lymphomas were low-grade B-cell and T-cell lymphomas (6/50, 12% and 4/50, 8%, respectively). The most common morphologic types were high-grade centroblastic and unclassifiable plasmacytoid for B- and T-cell lymphomas (18/50, 36% and 7/50, 14%, respectively).

Determination of cardiac troponin I in the blood and heart of calves with foot-and-mouth disease

The current study was designed to determine the changes of the cardiac troponin I (cTnI) expression in blood and tissue during the myocardial degeneration in calves with foot-and-mouth disease (FMD). Seventeen crossbred calves presenting pathological signs for FMD confirmed by viral analysis were studied. A biochemistry panel and immunohistochemistry were performed on 17 diseased calves and 7 calves used as controls. Creatine kinase (CK), CK-myocardial band (CK-MB), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) activities were analyzed for both groups. Cardiac troponin I levels were measured by a commercially available enzyme-linked immunosorbent assay kit. Mean cTnI (14.8 ± 1.9 ng/ml) concentration and CK (573 ± 407 U/l), CK-MB (238 ± 37 U/l), AST (84 ± 7), and LDH (298 ± 29 U/l) activities were higher in FMD cases compared with controls. Immunohistochemistry revealed loss or depletion of cTnI expression in myocardium of all cases. None of the 7 controls showed loss of cTnI expression. Increased serum cTnI concentration correlated with myocardial injury and loss of cTnI immunolabeling in cardiomyocytes of calves with FMD.

The effects of dexmedetomidine on mesenteric arterial occlusion-associated gut ischemia and reperfusion-induced gut and kidney injury in rabbits.

OBJECTIVE We assessed the antioxidant activity of dexmedetomidine (Dex) administered during the ischemic period in a rabbit model of mesenteric ischemia/reperfusion (I/R) injury using biochemical and histopathological methods. METHODS A total of 24 male New Zealand white rabbits weighing between 2.5 and 3.0 kg were randomly divided into three groups: the sham group (Group S, n = 8), the I/R group (Group I/R, n = 8), and the I/R plus Dex treatment group (Group Dex, n = 8). In the I/R group, ischemia was achieved with 60 min of mesenteric occlusion. The sham group provided normal basal values. The rabbits in Group I/R were operated to achieve I/R. Group Dex received intravenous Dex 30 min after the commencement of reperfusion (10 μg/kg Dex was infused within 10 min, and then a maintenance dose of 10 μg/kg/h Dex was infused intravenously). For the measurement of tissue malondialdehyde, total antioxidant status, total oxidant status, lipid hydroperoxide levels, superoxide dismutase, catalase, and myeloperoxidase activity levels in the renal tissue samples of animals, the rabbits in each group were sacrificed 3 h after reperfusion. The histopathological examination scores were determined using the intestinal and renal tissues. RESULTS The mean malondialdehyde, total oxidant status, myeloperoxidase, and lipid hydroperoxide levels were significantly higher in Group I/R than in Groups S and Dex (P < 0.05). There also were significant decreases in the mean total antioxidant status, catalase, and superoxide dismutase activities in Group I/R compared with Groups S and Dex (P < 0.05). The histopathological examination scores of the intestinal and renal tissues were significantly higher in Group I/R compared with Groups S and Dex (P < 0.05). CONCLUSION Dex treatment may have biochemical and histopathological benefits by preventing I/R-related cellular damage of intestinal and renal tissues as shown in an experimental mesenteric ischemia model. The preference to use Dex for anesthesia during the mesenteric ischemia procedure may attenuate I/R injury in intestinal and renal tissues.

Immunohistochemical detection of pulmonary surfactant proteins and retroviral antigens in the lungs of sheep with pulmonary adenomatosis.

The lungs and mediastinal and bronchial lymph nodes from 26 sheep with ovine pulmonary adenomatosis (OPA) were examined. Microscopically, the tumour was disseminated throughout the lungs and displayed acinar or papillary growth. The neoplastic cells were cuboidal or columnar with clear cytoplasm and a low mitotic rate. Retrovirus antigen (Jaagsiekte Sheep Retrovirus Capsid Protein, JSRV CA) was demonstrated in the cytoplasm of tumour cells in the lung and lymph nodes by immunohistochemistry. The neoplastic cells had more diffuse and intense expression of pulmonary surfactant protein-A (SP-A) compared with the expression of SP-B or SP-C. SP-A and SP-B expression was localized to the apical cytoplasm of the neoplastic cells, whereas SP-C was most strongly expressed in the perinuclear area of the tumour cells. In the lungs of two sheep, low numbers of tumour cells expressed Clara cell secretory protein (CCSP). The nuclei of the neoplastic epithelial cells and of the germinal centre lymphocytes within the peribronchiolar lymphoid tissue expressed the proliferating cell nuclear antigen (PCNA). CD3(+) T lymphocytes infiltrated the pulmonary tissue and surrounded the neoplastic foci. The results of this study demonstrate that JSRV continues to replicate in neoplastic cells after they have been transformed, and that the neoplastic cells produce pulmonary surfactant proteins. A local T-cell response occurs within affected lungs.

Pyridine induction of cytochrome P450 1A1, iNOS and metallothionein in Syrian hamsters and protective effects of silymarin

An in vivo assessment for the protective effects of silymarin for pyridine toxicity was investigated through cytochrome P450 isoform CYP1A1 and inducible nitric oxide synthase (iNOS) activity prevention. Moreover, the effect of pyridine-induced oxidative stress on metallothionein I-II (MT), a scavenger of oxygen-derived free radicals, was investigated. Forty Syrian hamsters were allocated into 4 groups. Syrian hamsters were dosed with pyridine (400mg/kg) intraperitoneally with and without silymarin (200mg/kg daily by gavage) for 4 days. Pyridine induced diffuse degeneration and necrosis of the proximal and distal renal tubular cells; cloudy swelling, necrosis and hepatocellular atypia of the liver; and degenerative changes in the myocardium. The degree of pathological alterations was less severe with simultaneous silymarin application. CYP1A1, iNOS and MT expression levels were elevated in liver, kidney and heart in response to acute pyridine toxicity. Silymarin application abolished or significantly suppressed the induction of CYP1A1, iNOS and MT expressions in liver, kidney and heart of the pyridine-treated Syrian hamsters. Enhanced synthesis of MT by pyridine possibly implies a purposive cellular response to prevent damage caused by oxygen radicals. However, silymarin significantly reduced the oxidative-stress-inducing effect of pyridine as reflected by decreased synthesis of MT. These results suggest that through oxidant generation, pyridine may cause alteration of the metabolic ways, including nitric oxide-mediated CYP1A1 activity.

PROTECTIVE EFFECTS OF SILYMARIN ON FUMONISIN B1-INDUCED HEPATOTOXICITY IN MICE

The present study was conducted to investigate the effect of silymarin on experimental liver toxication induced by Fumonisin B1 (FB1) in BALB/c mice. The mice were divided into six groups (n = 15). Group 1 served as the control. Group 2 was the silymarin control (100 mg/kg by gavage). Groups 3 and 4 were treated with FB1 (Group 3, 1.5 mg/kg FB1, intraperitoneally; and Group 4, 4.5 mg/kg FB1). Group 5 received FB1 (1.5 mg/kg) and silymarin (100 mg/kg), and Group 6 was given a higher dose of FB1 (4.5 mg/kg FB1) with silymarin (100 mg/kg). Silymarin treatment significantly decreased (p < 0.0001) the apoptotic rate. FB1 administration significantly increased (p < 0.0001) proliferating cell nuclear antigen and Ki-67 expression. Furthermore, FB1 elevated the levels of caspase-8 and tumor necrosis factor-alpha mediators while silymarin significantly reduced (p < 0.0001) the expression of these factors. Vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) expressions were significantly elevated in Group 4 (p < 0.0001). Silymarin administration alleviated increased VEGF and FGF-2 expression levels (p < 0.0001). In conclusion, silymarin ameliorated toxic liver damage caused by FB1 in BALB/c mice.

Cyclin A expression is associated with apoptosis and mitosis in murine 3-methylcholanthrene-induced fibrosarcomas.

The chemical carcinogen MCA induces fibrosarcoma and tissue damage at the injection site. Despite the importance of ROS in the development of cancer, little is known about the pattern of expression of ROS in MCA-induced fibrosarcomas. To gain some insight into the biological significance of iNOS and Cu/Zn-SOD, comparative immunohistochemical analyses were performed to characterize their expression in MCA-induced fibrosarcomas. Cyclin A is overexpressed in various tumors, but its expression in MCA-induced fibrosarcoma in mice and its correlation to mitosis and apoptosis are unclear. The presence of apoptotic cell death was evaluated using the TUNEL method and findings were compared with cyclin A expression and mitotic count of fibrosarcomas. Subcutaneous application of MCA caused fibrosarcoma development in 14 of 20 mice (70%) in 26 weeks. Limited cytoplasmic Cu/Zn-SOD and iNOS immunostainings were detected in 13 of 14 and 9 of 14 tumors with median immunoreactive scores of 2 and 1, respectively. Prominent nuclear cyclin A immunostaining and TUNEL-positive reactions were seen in all the fibrosarcoma cases. Cyclin A immunoreaction significantly correlated with the TUNEL index (P<0.01) and MC (P<0.001). The present findings show a low level of iNOS expression in neoplastic cells indicating limited synthesizing capacity of tumor cells. Limited Cu/Zn-SOD reaction could be associated with an imbalance in between pro-oxidant/antioxidant levels. Furthermore, it was shown that cyclin A is overexpressed in MCA-induced fibrosarcomas and possibly plays a significant role in the pathogenesis of fibrosarcomas. Cyclin A could be useful for detecting the S phase of the cell cycle and could also indicate that cyclin A may induce S phase arrest associated with apoptosis in the MCA-induced fibrosarcomas.

Occurrence of Helicobacter Infection in the Gastric Mucosa of Free-living Red Foxes (Vulpes vulpes)

We studied gastric Helicobacter spp. in five red foxes (Vulpes vulpes). Samples of stomach from the cardia, corpus, pyloric antrum, and duodenum were subjected to histopathologic, immunohistochemical, and transmission electron microscopy (TEM) examination for the presence of Helicobacter and gastritis. All foxes had gastric Helicobacter-like organisms (GHLOs) on examination by light microscopy and TEM. Gastric Helicobacter-like organisms were present in all areas of the stomachs. Chronic mild or moderate gastric inflammation was associated with infection by GHLOs in one or more regions of the stomach, but there was no correlation between inflammation and infection. It is not clear whether the organisms were causing the minimal histologic lesions observed, but the gastric mucosa of free-living foxes appears to be commonly colonized with GHLOs. The frequent colonization of free-living foxes with distinct GHLOs possibly reflects their special characteristic in feeding and/or social behavior or the potential commensal nature of the bacteria in free-ranging foxes.

Meibomian carcinoma of the eyelid in a Simmental cow.

OBJECTIVE To describe the clinical and pathomorphological features of meibomian carcinoma (MC) diagnosed in a Simmental cow. MATERIAL AND METHODS A 7-year-old Simmental cow was admitted to the Veterinary Surgery Clinics of Faculty of Veterinary Medicine, University of Kafkas, Kars, Turkey. The signalment and anatomical distribution were summarized and focused on pathomorphological description. RESULTS Macroscopically, a papillary mass, 5 × 3.5 × 7 cm in size, arising from the left lower eyelid with local spread to the upper eyelid and covering the entire globe was observed. The mass was ulcerated and hemorrhagic and applied pressure to the globe. Following sedation and local anesthesia, the mass and globe were excised. Histopathological examination revealed an MC. CONCLUSIONS The diagnosis of MC is infrequent in veterinary literature. Complete surgical excision could be curative and histopathology is crucial for the diagnosis of MC occurring in animals.

Immunohistochemical characterization of peroxisome proliferator-activated receptors in canine normal testis and testicular tumours.

Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors belonging to the nuclear hormone receptor superfamily. Recent studies have demonstrated that PPARs regulate lipid metabolism and are expressed in various cancers. The aim of the present study was to investigate the expression of PPAR-α, -β and -γ in normal canine testicular tissue and canine testicular tumours (CTTs). Expression of PPAR-α, -β and -γ was greater (P <0.05) than in normal testicular tissue. PPARs were therefore induced in CTTs and they may play a role in the biology of these tumours.