Biomedical subjects

N Kannan

Publications and source records attributed to N Kannan.

40 records · Page 3Linked to original sources

PubMedDate not supplied

Toxic chlorobiphenyls in adipose tissue and whole blood of an occupationally/accidentally exposed man and the general population.

Individual polychlorinated biphenyl (CB) congeners in adipose and whole blood tissues of a capacitor manufacture worker (occupational/accidental exposure) and of the general population were determined. Nondestructive sample cleanup and multidimensional gas chromatography-electron capture detection (MDGC-ECD) techniques were applied. Special attention was given to the toxicologically relevant congeners CB-77, CB-126, CB-169, CB-105, CB-114, CB-118, CB-156, CB-167, and CB-189 (IUPAC). Lipid-based tissue contents of sigma CBs were higher in the occupationally/accidentally exposed worker (adipose = 7,000 ng/g; whole blood = 11 ng/g) than in the general population (adipose = 300 ng/g; whole blood = 1.9 ng/g). Among the non-ortho Cl CBs, CB-77 was below detection limit (< 1.0 pg/g). The contents of CB-126 for the capacitor manufacture worker were 2,000 and 3 pg/g, and in the general population were 100 and 2 pg/g for adipose and whole blood, respectively. The corresponding data for CB-169 were 3,500 and 4 for adipose and whole blood, respectively, in the exposed worker, and 40 and 2 for adipose and whole blood, respectively, in the general population. Congeners with highest contents were CB-153, CB-138, CB-180, CB-170, and CB-187. These congeners possess chlorine substitution patterns, making them resistant to metabolism. X/153 ratios suggest that both PB and 3-MC type cytochrome P-450 enzymes were induced in the exposed worker, as well as in the general population.

Adipose Tissue↗

PubMedDate not supplied

Evaluation of glycoproteins as prognosticators in head and neck malignancy.

Although several serum glycoprotein assays have been conducted for identifying tumor markers and prognosticators of malignancies, presently assessment of effectiveness of treatment of these malignancies remains subjective and good and effective tumor markers and prognosticators of head and neck malignancies are yet to be identified. In our study, serum samples from forty patients with head and neck cancers who were divided into four groups of ten patients each on the basis of their clinical staging and serum samples from ten healthy individuals comprising the control group was taken and subjected to biochemical analysis of serum protein bound hexose, serum fucose, serum sialic acid levels before starting treatment of the cancers and after completion of the cancer treatment and compared with the levels of these serum glycoproteins amongst the control group. All the head and neck cancer patients showed elevated levels of the serum glycoproteins as compared to the control group. It was further noted that the increased levels of the serum glycoproteins correlated well with the clinical staging of the malignancies. Post-treatment levels of all the serum glycoproteins were decreased significantly but, only the serum sialic acid level in 6 out of 10 patients with stage-I malignancy returned to the base line levels as seen in the control group. Serum sialic acid levels showed very close correlation with tumor staging and maybe considered as a good tumor marker and prognosticator for detection of cancer and evaluation of effectiveness of treatment of head and neck malignancies.

Biomarkers, Tumor↗

PubMedDate not supplied

Variables influencing regularity of leprosy patients in attending treatment clinics.

Regularity in attending clinics as well as taking drugs assume a very significant place in leprosy control programme since irregularity of leprosy patients can lead to poor disease control, drug resistant disease, and development of physical deformities and disabilities thus leading to programme failure. Further, these complications also create socio-economic and psychological problems to the victims as well as their families in myriad ways. This paper reports a study aimed at identifying the variables, among a set of 29 selected demographic, socio-economic and disease-related variables, having significant association with regularity of leprosy patients in attending treatment clinics. It was found that age of the patients, type of family, duration of the disease, time lag between diagnosis of the disease and starting treatment and knowledge of patients and their families about the disease were significantly associated with treatment regularity.

Adult↗

PubMedDate not supplied

Coplanar polychlorinated biphenyls in aroclor and kanechlor mixtures.

Three congeners of coplanar PCBs (non-o-o'-chlorine-substituted polychlorinated biphenyls) were determined in representative commercial PCB preparations. The 3,3',4,4'-tetrachlorobiphenyl was highest in Kanechlor 400 (8500 micrograms/g) and Aroclor 1248 (6060 micrograms/g) followed by Kanechlors 300, 500, and 600 and Aroclors 1242, 1254, and 1260 in that order. The toxic 3,3',4,4',5-pentachlorobiphenyl and 3,3',4,4',5,5'-hexachlorobiphenyl were also detected in those mixtures. The highest concentrations of 3,3',4,4',5-pentachlorobiphenyl were found in Kanechlor 400 (89.3 micrograms/g) and Aroclor 1248 (62.3 micrograms/g) followed by Kanechlors 500, 300, and 600 and Aroclors 1254, 1242, and 1260 in that order. The 3,3',4,4',5,5'-hexachlorobiphenyl was detected in all Kanechlor mixtures, with the highest concentration (1.16 micrograms/g) in Kanechlor 500. However, among Aroclor mixtures, it was detected only in Aroclor 1254 at a concentration of 0.66 micrograms/g. The importance of these toxic constituents in PCB mixtures is worth considering in view of widespread pollution of the environment by PCBs.

Aroclors↗