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Biomedical subjects

T Vijayakumar

Publications and source records attributed to T Vijayakumar.

At least 55 records · Page 3Linked to original sources

A rare human model for oncogenesis.

A rare female human model of oral carcinoma (OC) who refrained from any type of tobacco and/or betel nut habits, belonged to an younger age group, had no pre-existing precancerous lesions in the oral cavity and who was exposed chronically to cashew nut oil, is presented. The role of genetic inherited influences, occupational and endocrine disturbances with racial factors in the causation of oral carcinoma is discussed. The significance of further studies at the genetic level, to rule out protooncogenic activation in the causation of oral cancer is summed up. The literature on the concept of oncogenesis is reviewed briefly.

Adolescent↗

Total hemolytic complement (CH50) and its fractions (C3 and C4) in the sera of patients with carcinoma of the oral cavity, uterine cervix, and breast.

The total hemolytic complement activity of CH50 and its fractions C3 and C4 was determined in the sera of 196 patients with carcinoma of the oral cavity, 172 patients with carcinoma of the uterine cervix, and 166 patients with breast cancer. The values were compared with those of 18 patients with mammary dysplasia, 32 patients with mild to moderate dysplasia of the cervix, and 100 healthy, normal age- and sex-matched controls. No alterations in CH50, C3, and C4 were observed in the sera of patients with benign lesions, whereas a significant rise in the three factors was observed in all the cancer patients studied. The complement activity increased significantly with the progression of the disease up to stage III and remained persistently elevated thereafter. Patients who had a clinical cure had normal levels of CH50, C3, and C4, whereas the values remained elevated in patients who were still undergoing treatment for residual lesions.

Adult↗

Serum copper and zinc levels in premalignant and malignant lesions of the oral cavity.

Serum levels of copper and zinc were analysed in 50 patients with oral cancer, 50 patients with oral leucoplakia, and 50 patients with oral submucous fibrosis, and the values were compared with those of 50 normal healthy adult controls. There was a significant reduction in the serum copper and zinc levels in both oral submucous fibrosis and oral cancer. The copper/zinc ratio was found to be elevated in oral submucous fibrosis and depressed in oral cancer. The ratio may serve as a good indicator for the early detection of oral cancer.

Adult↗

Tissue staining properties of lectins from the seeds of the jack fruit (Artocarpus integrifolia) and the winged bean (Psophocarpus tetragonolobus).

N-acetyl-D-galactosamine binding lectins from winged bean (Psophocarpus tetragonolobus) and jack fruit (Artocarpus integrifolia) were isolated, purified and conjugated with horse radish peroxidase and their tissue staining properties studied. Despite having an apparently common inhibiting sugar, the lectins showed differences in their staining properties. The lectin from the winged bean stained none of the mouse and human tissues tried even after neuraminidase treatment whereas the jack fruit lectin stained most of the untreated cells. The staining was found to be improved by the prior treatment of the cells with neuraminidase and inhibited completely by the inhibiting sugar. The differences in the staining properties of the lectins are discussed.

Animals↗

Demonstration of HSV-I antigen in patients with oral cancer by immunofluorescence and immunoperoxidase techniques.

Biopsies from one hundred and seventy five patients suffering from carcinoma of the oral cavity were examined for the presence of Herpes simplex virus Type 1 (HSV-1) antigen, using Immunofluorescence (Direct and indirect) and immunoperoxidase techniques. Seventy-seven percent of the biopsies showed significant fluorescence, while 71% showed positivity with immunoperoxidase staining. There was no correlation either in the degree of fluorescence or in the intensity of peroxidase staining with clinical stage of the disease. Normal oral biopsies showed 30% and 20% positivity in immunofluorescence and immunoperoxidase respectively. In the case of oral cancer cells, the fluorescence was very much diminished when HSV-1 antiserum was absorbed with specific homologous virus-infected Vero cells.

Animals↗

Tissue binding patterns of lectins in premalignant and malignant lesions of the oral cavity.

Lectins from the seeds of Jackfruit (Artocarpus integrifolia) and winged bean (Psophocarpus tetragonolobus) were isolated using an immobilized N-acetyl D-galactosamine column and conjugated to type VI horse radish peroxidase. The purified conjugate was used for the study of tissue specificities using diaminobenzidine as the substrate on dewaxed tissue sections of normal, oral leukoplakia, oral submucous fibrosis, verucous carcinoma and squamous cell carcinoma of the oral cavity. In spite of having a common inhibitory sugar, winged bean lectin did not bind to any lectins whereas Jackfruit lectin showed varying degrees of binding towards the above tissues. The difference in the nature and intensity of binding of the Jackfruit lectin suggest the utilizing this lectin in the differential diagnosis of the premalignant and malignant lesions of the oral cavity.

Carcinoma, Papillary↗

Cell mediated and humoral immune responses in oral submucous fibrosis.

Cell-mediated and humoral immune responses were assessed in 50 patients with oral submucous fibrosis (OSMF) and the results were compared with those of 50 patients with oral-leukoplakia, 50 oral cancer patients, and 50 normal healthy adult controls. The number of high-affinity rosette-forming cells (HARFC) was found to be significantly decreased in OSMF and oral cancer, whereas the number of total rosette-forming cells (TRFC) remained unaltered. Levels of serum IgA, IgD, and IgE were found to be elevated both in OSMF and oral cancer. Immunologic derangements were found to be more pronounced in oral cancer than in OSMF. The enumeration of HARFC along with the estimation of serum levels of IgA, IgD, and IgE indicates that OSMF can be an intermediary stage in the malignant transformation of a normal cell, and that these parameters may serve as markers for the early detection of oral cancer.

Adult↗

Serum immunoglobulins in patients with carcinoma of the oral cavity, uterine cervix and breast.

Serum immunoglobulin levels (IgG, IgA, IgM, IgD and IgE) were estimated in 196 patients with carcinoma of the oral cavity, 172 patients with cervical cancer and 166 patients with breast cancer. The values were compared with those of 50 patients with benign lesions of the breast and cervix and 100 healthy adult controls. Only the serum IgE levels were found to be elevated in the benign group. Serum IgA, IgD and IgE levels were found to be elevated in all the three types of cancers and the levels were found to increase with clinical stage. In carcinoma of uterine cervix IgG levels were also found to be elevated. Immunoglobulins A and D returned to normal after clinical cure whereas IgE remained slightly elevated. IgD and IgE remained high in patients who had residual cancer.

Adult↗

High affinity rosette forming cells in carcinoma of the oral cavity, uterine cervix and breast.

Total rosette forming cells (TRFC) and high affinity rosette forming cells (HARFC) were enumerated in 534 patients with carcinoma of oral cavity, uterine cervix or breast, and the results were compared with adult controls. The HARFC levels were found to be significantly decreased in cancer patients, and this decrease was more pronounced in advanced clinical stages. The HARFC levels returned to normal in patients who had a clinical cure but remained low in patients having residual disease. Enumeration of HARFC may therefore be useful in assessing the cell mediated immunity in cancer patients.

Adult↗

Renal involvement in leprosy.

Renal involvement in 13 non-lepromatous and 17 lepromatous leprosy patients were assessed by routine urinalysis, detailed biochemical analysis of blood and urine and by renal histopathological studies and compared with 10 normal healthy controls. The presence of RBC and pus cells were detected in the urinary deposit of only one lepromatous leprosy patient in reactional phase. A reversal of albumin/globulin ratio was observed in 17.6% of non-lepromatous and 15.3% of lepromatous patients. 24 hours urinary excretion of sodium, potassium, chloride and aminonitrogen of the patients were within the normal range. Forth seven percent of the non-lepromatous and 46% of the lepromatous patients had proteinuria. Even though the mean serum creatinine values of the patients showed no difference from that of the normals, the creatinine clearance was low in 82.3% of the non-lepromatous and in all of the lepromatous patients. Serum phosphorus, serum uric acid, urinary phosphate excretion and the renal tubular reabsorption of phosphorus of the patients were normal. Twenty one percutaneous renal biopsy specimens showed nonspecific pathological changes such as nephritis of various varieties in 71.4% of the specimens. Among the lepromatous group renal involvement was observed in 5 out of 9 cases (55.6%) and in the non-lepromatous group 10 out of 12 cases (83.3%). No acid fast bacilli, amyloid and granuloma were seen in any of the renal tissues studied. There was no definite correlation between the type of renal pathology and biochemical changes. None of the patient showed any clinical evidence of renal involvement.

Adolescent↗

Liver in leprosy - II. Histopathological changes.

Liver biopsy studies were conducted in 77 leprosy patients. The first group of 42 patients were not on any treatment, whereas the 28 patients in the second group were being treated for varying periods. The rest 7 patients in the third group were clinically quiscent. Microscopic changes in the liver biopsy specimens were mainly epitheloid cell granuloma, foam cell granuloma, nonspecific inflammatory reaction characterised by lymphocytes and polymorpho nuclear leukocytes, and to a lesser degree hepatocytolysis and fatty degeneration. The lesions were fewer in the group getting treatment compared to the untreated group.

Humans↗

Liver in leprosy--I. Functional changes.

Liver function tests were carried out in 79 leprosy patients, out of which 28 patients were being treated and 42 patients were not receiving any treatment. The rest 9 patients were clinically quiescent. In the untreated group there were 28 tuberculoid and 14 lepromatus cases. The 28 patients receiving treatment were composed of equal number of lepromatus and tuberculoid groups. The liver function tests of 10 of the untreated tuberculoid patients were repeated after six months of specific therapy with D.D.S. The values of liver function tests of these patients were compared with that of 20 normal adults. The most important abnormality observed in the patients were a reversal of albumin/globulins ratio which was more common in the lepromatus group than in the tuberculoid group. Treatment with D.D.S. has resulted in the reduction of the serum globulin. There were no changes in transaminases and alkaline phosphatase activities in the untreated patients. But however a rise in the above enzymes were observed in patients on treatment. The mean serum cholesterol values of the patients were lower than that of the controls.

Alkaline Phosphatase↗