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2017 - 20203
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Subject: Veterinary Pathology × End date: 2020 × Start date: 2017 × Thesis Type: Ph.D ×
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    ThesisItemOpen Access
    HISTOPATHOLOGICAL EVALUATION AND IMMUNOHISTOCHEMICAL DETECTION OF CERTAIN TUMOR MARKERS OF CANINE MAMMARY TUMORS
    (SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA, 2020-10) SUDHA RANI CHOWDARY, CH.; RAMA DEVI, V (MAJOR); SATHEESH, K; RAVI KUMAR, P; SUDHAKAR, K
    The present study was undertaken to know the occurrence of canine mammary tumors (CMTs), to classify and study their gross and microscopic lesions, evaluate different tumor markers by IHC and to determine the variations of p53 gene in CMTs. In the present study, the animals with mammary tumors ranged from 1.5 to 14 years of age with highest occurrence in 9-10 years age group and noticed only in female dogs. Highest occurrence of canine mammary tumors was recorded in non-descript dogs followed by Spitz and German Shepherd breeds. The occurrence was highest in intact bitches when compared to spayed dogs. Out of 72 cases, 47 cases had a single mammary gland affected whereas 25 cases had tumors in multiple glands. The highest occurrence was recorded in the inguinal (50.49%), followed by caudal abdominal (33.98 %) glands. Majority of the cases showed TNM stage III tumors (59.42%), followed by stage II (21.74%), stage IV (8.7%), stage V (7.25%) and stage I tumors (2.90%). Overall, the cytological diagnosis had 75% correlation to histopathological diagnosis. The cytologic diagnosis correlated with the histologic diagnosis for benign and malignant tumors in 60 and 79.59% of cases respectively. Grossly, the size of the tumors ranged from 2 to 19 cm in greatest diameter with different shapes and consistencies. Sixty three cases (87.5%) had malignant tumors and 9 cases (12.5%) showed benign tumors. Histologically, they were classified into 20 major subtypes and among them, solid carcinoma had the highest frequency (20.6%), followed by complex carcinoma (15.9%), intraductal papillary carcinoma (14.3%). In the present study, metastasis of CMTs to lymphatic vessels, lymph nodes and visceral organs was recorded in 13 cases (18.1%). Maximum number of carcinomas were of grade II (46.7%) followed by grade III (40%) and grade I category (13.3%). The mean AgNOR number per cell ranged from 1.1 to 6.7 and was higher (4.58) in malignant tumors than in benign tumors (1.4). Of the 72 CMTs subjected to immunostaining of different tumor markers, 38.9% of tumors showed Ki-67 expression, 37.5% and 25% of CMTs showed ERα and PR expression respectively, whereas 89.1%, 25% and 16.7 % of the cases showed VEGF, survivin and p53 expression respectively. Of the 20 CMTs subjected to molecular studies, three mutations in exon 4 were detected in two tumor tissues which included two missense mutations in a complex carcinoma and a silent mutation in a carcinosarcoma. However, concordance of p53 phenotype and p53 genotype was found only in one case which had a silent mutation. On Kaplan - Meier analysis, early TNM stage, positive expression of ERα and PR, negative expression of p53 and survivin were found to be associated with longer overall survival. However, only TNM stage and PR expression were found to be independent prognostic factors on multivariate analysis. In the present study, various factors such as tumor stage, histological grade and features, expression of different tumor markers and p53 gene variations along with epidemiological data were evaluated in CMTs. It was revealed that the factors like TNM stage and PR expression have significant prognostic value and can influence the clinical outcome of canine mammary tumors.
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    ThesisItemOpen Access
    PATHOLOGICAL AND MOLECULAR STUDIES ON JSRV (JAAGSIEKTE SHEEP RETROVIRUS) IN SHEEP AFFECTED WITH OVINE PULMONARY ADENOCARCINOMA IN ANDHRA PRADESH
    (SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517502. (A.P.) INDIA, 2019-11) SAMATHA, V; RAMA DEVI, V (MAJOR); SATHEESH, K; SUBRAMANYAM, K.V.; VINOO, R
    Ovine pulmonary adenocarcinoma (OPA) is a naturally occurring transmissible tumor of lungs in sheep and goats caused by an exogenous Jaagsiekte Sheep Retrovirus (exJSRV). A major obstacle in JSRV research is the difficulty to culture the etiological agent in vitro and absence of serological tests for diagnosis. Of late, PCR diagnostic techniques are being used to diagnose OPA at field level. There are reports of OPA from India, but molecular studies on JSRV are lacking. The present work was planned to study the gross and microscopic lesions and to carry out molecular diagnosis along with molecular characterization of JSRV by sequencing U3, gag and Env-TM genes. In addition, exons of 5, 7 and 8 of p53 gene in OPA tumors were sequenced to determine any mutations. The materials for the present study were collected from slaughter houses, private organized farms and from field mortalities. A total of 150 lung samples were collected and of these, 22 samples were found positive for OPA based on gross, histopathology and by molecular diagnosis of JSRV by U3-hnPCR. Grossly, the lung samples from OPA cases revealed diffuse areas of consolidation or tumor nodules and the cut surface had meaty appearance with moist surfaces resembling classical form of OPA. Histologically, sections from consolidated and/or nodular areas of lungs revealed multiple nonencapsulated neoplastic areas of different sizes composed of cuboidal to columnar epithelium lining the alveolar and bronchiolar walls.The neoplastic epithelium was mainly arranged in two typesviz. papillary or acinar growth patterns. In few lungs, bronchioloalveolar growth pattern was noticed. In advanced cases, thickening of alveolar septa was noticed due to connective tissue proliferation and cellular infiltration in the interstitium. Myxomatous nodules were evident in some areas. Immunostaining for JSRV-CA protein was performed on eight OPA lung samples and the positive staining was indicated by the presence of intracytoplasmic fine brown granular staining of the neoplastic cells, alveolar macrophages and desquamated tumor cells. RNA was extracted from the suspected OPA lungs and lymph node tissues and cDNA was prepared and was amplified by U3-hn PCR to detect JSRV transcripts using specific primers. A total of 22 sheep (14.7%) were found positive for OPA out of 150 animals examined. cDNA prepared from 22 OPA lung samples was used for conducting PCR to amplify gag and Env-TM genes of exJSRV. A PCR that was specific for the exons 5,7 and 8 of p53 gene in lung tumor tissues of OPA was performed and an amplified products of 332 bp,210 bp and 220 bp were detected respectively. The PCR amplicons obtained in different reactions were sequenced by Sanger dideoxychain termination method at Bioserve Biotechnologies Pvt. Ltd, Hyderabad. All the sequences were aligned and the deduced sequences were submitted to GenBank. Pair wise divergence and similarity was calculated using MEGA 7. The nucleotide sequence analysis of five JSRV sequences (samples 4-8) from the OPA affected sheep for U3 region of exJSRV showed more similarity (81-98%) with a UK strain (AF105220.1) than (69-73%) with a South African strain (M80216). The phylogenetic analysis of these sequences revealed that they were slightly divergent from other Gannavaram isolates available in the database. The nucleotide sequence analysis of eight JSRV sequences (samples 1-8) from the OPA affected sheep for gag region of exJSRV showed similarity (99-100%) with both enJSRV NTRCVSc_enJSRV 1 to 12) and (100%) a few exJSRV (MG192314, MG192315, MG192316 and DQ838494). The absence of Sca1 site was noticed. The present sequences were similar to exJSRV isolates reported from Delhi and China. The nucleotide sequence analysis of four exJSRVsequences (samples 4-7) from the OPA affected sheep for Env-TM region showed more similarity (94-9%) with UK strain (AF105220.1) and (92-94%) with USA strains (AF357971) than (80-82%) South African strain (M80216). The region of cytoplasmic tail obtained is incomplete in its aminoterminal, but the information revealed conservation of YX part of the YXXM motif of the exJSRV. The nucleotide sequence analysis of p53 gene at exons 5,7 and 8 in OPA tumor samples revealed no mutations that may suggest involvement of other regions of p53 or alternative genes in development of OPA. Based on the pathological and molecular studies carried out on OPA affected lung tissues of sheep, the JSRV sequences obtained were characterized as exogenous JSRV.
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    ThesisItemOpen Access
    MOLECULAR AND PATHOLOGICAL STUDIES OF INDUCED HYPERLIPIDEMIA AND ATHEROSCLEROSIS IN RATS AND ITS AMELIORATION WITH FLAXSEEDS (LINUM USITATISSIUMUM) AND GREEN TEA (CAMELLIA SINENSIS)
    (SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA, 2017-05) SRINIVASA NAIK, H; SRILATHA, Ch(MAJOR); SUJATHA, K; SREEDEVI, B; PRASAD, T.N.V.K.V
      ABSTRACT : Hyerlipidemia is the disorder of lipid metabolism, characterized by elevated serum total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C) and very low density lipoproteins cholesterol (VLDL-C) and decreased high density lipoprotein cholesterol (HDL-C). Atherosclerosis is diverse disease with heterogenous mechanisms of progression and is an oxidative, chronic inflammatory and thrombotic disease referring to fatty deposits on the inner lining of the large to medium sized elastic and muscular arteries and is precipitated by elevated level of low density lipoprotein cholesterol (LDL-C) in the blood. Atherosclerosis associated coronary heart disease is the second largest cause of mortality worldwide in humans. Current reports suggest that by the year 2020, India will have the largest cardio vascular disease (CVD) burden in the world. Realizing the importance of ethno medical practices, flaxseed and green tea supplementation along with atherogenic diet has been taken to combat the hyperlipidemia associated atherosclerosis. Flaxseed (Linumusitatissiumum) has been identified as a significant alternative source of omega 3 fatty acids and alpha linoleic acid (ALA). Therapeutic activities of flaxseed is well proven, one of them is anti-atherosclerotic due to its lipid lowering activity which is mainly attributed to its Secoisoarciresinol diglucoside (SDG). Green tea (Camellia sinensis) polyphenols known to have various medical health beneficial effects like anti-inflammatory, anti-oxidative, anti-arthritic, anti angiogenic, anti-metastatic, anti-cancer, anti-obesity, anti hyperlipidemic, anti-atherosclerotic, neuroprotective, anti-dental caries and antimicrobial (bacterial, viral & fungal) properties in human, animal and in vitro studies. So the present study was designed with a view to study molecular aspects of hyperlipidemia associated atherosclerosis in male Wistar albino rats and an attempt was made to identify various molecular preventive effects of flax seeds (Linumusitatissiumum) and green tea (Cameliasinensis). The present study was carried out by procuring 72 wistar albino rats, that were randomly divided into six groups consisting of 12 rats in each group. Hyperlipidemia associated atherosclerosis was induced by atherogenic diet consisting of 1% cholesterol and 15% saturated oil added to the 1000g of standard rat diet and given to group II rats. Flaxseed @ 7.5g/kg/day and green tea @ 100mg/kg/day gavaged orally to group V and VI rats for 90 days along with atherogenic diet. Group I kept as control and given standard rat diet, group III as flaxseed control and given 7.5g/kg/day of flaxseed along with standard rat diet, whereas group IV kept as green tea control and given 100mg/kg/day/Po along with standard rat diet for 90 days. Six rats from each group were sacrificed 45 days apart each. Atherogenic diet fed group (Group II) rats clinically showed obesity with significant increase (p<0.05) in the body weight. Rats were sluggish with poor hair coat. Green tea supplementation (Group VI) significantly reduced the obesity and body weight compared to moderate reduction of obesity and body weight in flaxseed ameliorated group (Group V). Whereas green tea control group (Group IV) rats were apparently healthy, slim with shiny hair coat. Total leukocyte count (TLC), total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C) were significantly (p<0.05) higher, whereas high density lipoprotein cholesterol (HDL-C) was significantly reduced in group II. Oxidative damage indicators like catalase, SOD, GPx, reduced glutathione and glutathione S transferase were significantly (p < 0.05) reduced, whereas lipid peroxidation products of TBARS level was non-significantly (p < 0.05) increased in liver and heart tissues of atherogenic diet fed group (Group II). Flaxseeds supplementation (Group V) reduced the hyperlipidemia certain extent caused by atherogenic diet by reducing the modest level of TC, TG, LDL-C and mild elevation of HDL-C. Flaxseeds non-significantly (p < 0.05) increased the cellular anti-oxidant enzymes and modestly reduced the level of TBARS. Whereas green tea (Group VI) supplementation effectively controlled the hyperlipidemia by reducing all the serum total cholesterol, triglycerides, low density lipoprotein cholesterol and very low density lipoprotein cholesterol and enhanced the good high density cholesterol and significantly (p < 0.05) enhanced all the tissue anti-oxidant enzymes and modestly reduced the TBARS levels. Microscopically hepatic steatosis was prominent in atherogenic diet fed group (Group II). Complete absence of fatty change was evident in green tea treated group (Group VI) compared to flaxseed group (Group V). Histopathologically, endothelial degeneration, sub intimal fat cells, foam cells with attached microthrombi was observed in majority of the cases in group II rats aorta fed on atherogenic diet. All these changes were also evidenced by ultrastructural studies. Mild endothelial degeneration was evident in flaxseed ameliorated group. Majority of the changes of initiated atherosclerosis were minimized by green tea supplementation. No such lesions were seen in control, flaxseed and green tea alone fed control groups (Group I, III & IV) throughout the study period. Mild endothelial cell proliferation with formation of vascular channels in between cardiac muscle fibers, liver and in kidney was observed throughout the study period of flaxseed fed group (Group III) rats. VEGF positivity was observed in endothelial cells, thrombus and structurally modified stromal cells of initiated atherosclerotic lesion. Initiated atheromatous plaque showed high level of positivity with Bax compared with other parts of blood vessel. On the other hand, selective moderate to severe positivity with CD 31, CD44, E cadherin and Beta catenin was observed in the initiated atherosclerotic lesion characterized by endothelial degeneration, sub endothelial lipid laden macrophages, and endothelial adhered thrombus and erythrocytes. Various levels of positivity with above markers was also observed in flaxseed and green tea ameliorated groups based on the initiated atherosclerotic lesion in these groups. Present study revealed positive expression of proinflammatory cytokine TNF alpha by RT-PCR (Real time PCR) in atherogenic diet fed group aorta (Group II) compared to standard diet fed rats (Group I). Flaxseed and green tea ameliorated groups (Group V and VI) showed significant reduction in the expression of TNF alpha in contrary to atherogenic diet fed group (Group II). IL-18 expression was not noticed in any groups of the present study. In conclusion atherogenic diet of present study established the hyperlipidemia and initiated the atherosclerosis in the aorta evidenced by histopathology and molecular expression of PECAM-I (CD 31), CD44, E cadherin and Beta catenin and tissue TNF alpha. Flaxseeds supplementation reduced the hyperlipidemia associated atherosclerosis to certain extent, but not completely ameliorated the changes. On the other hand, green tea supplementation effectively controlled the hyperlipidemia associated atherosclerosis and enhanced all the tissue anti-oxidant enzymes.