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Biomedical subjects

V Manoharan

Publications and source records attributed to V Manoharan.

7 recordsLinked to original sources
PubMed2006

Interactive effects of soil acidity and fluoride on soil solution aluminium chemistry and barley (Hordeum vulgare L.) root growth.

A greenhouse study was conducted to determine if concentrations of fluoride (F), which would be added to acid soils via P fertilisers, were detrimental to barley root growth. Increasing rates of F additions to soil significantly increased the soil solution concentrations of aluminium (Al) and F irrespective of the initial adjusted soil pH, which ranged from 4.25 to 5.48. High rates of F addition severely restricted root growth; the effect was more pronounced in the strongly acidic soil. Speciation calculations demonstrated that increasing rates of F additions substantially increased the concentrations of Al-F complexes in the soil. Stepwise regression analysis showed that it was the combination of the activities of AlF2(1+) and AlF(2+) complexes that primarily controlled barley root growth. The results suggested that continuous input of F to soils, and increased soil acidification, may become an F risk issue in the future.

Aluminum↗
PubMed2005

Management of mine spoil for crop productivity with lignite fly ash and biological amendments.

Long-term field trials using lignite fly ash (LFA) were carried out in rice crops during the period 1996-2000 at Mine I, Neyveli Lignite Corporation, Tamil Nadu. LFA, being alkaline and endowed with an excellent pozzolanic nature, silt loam texture, and plant nutrients, has the potential to improve the texture, fertility, and crop productivity of mine spoil. The rice crops were the first, third, fifth, and sixth crops in rotation. The other crops, such as green gram (second) and sun hemp (fourth), were grown as green manure. For experimental trials, LFA was applied at various dosages (0, 5, 10, 20, 50, 100, and 200 t/ha), with and without press mud (10 t/ha), before cultivation of the first crop. Repeat applications of LFA were made at the same dosages in treatments of up to 50 t/ha (with and without press mud) before cultivation of the third and fifth crops. Press mud, a lightweight organic waste product from the sugar industry, was used as an organic amendment and source of plant nutrients. Also, a recommended dosage of chemical fertilizer, along with gypsum, humic acid, and biofertilizer as supplementing agents, was applied in all the treatments, including control. With one-time and repeat applications of LFA, from 5 to 20 t/ha (with and without press mud), the crop yield (grain and straw) increased significantly (p < 0.05), in the range from 3.0 to 42.0% over the corresponding control. The maximum yield was obtained with repeat applications of 20 t/ha of LFA with press mud in the third crop. The press mud enhanced the yield in the range of 1.5-10.2% with various dosages of LFA. The optimum dosage of LFA was 20 t/ha for both one-time and repeat applications. Repeat applications of LFA at lower dosages of up to 20 t/ha were more effective in increasing the yield than the corresponding one-time applications of up to 20 t/ha and repeat applications at 50 t/ha. One-time and repeat applications of LFA of up to 20 t/ha (with and without press mud), apart from increasing the yield, evinced improvement in the texture and fertility of mine spoil and the nutrient content of crop produce. Furthermore, some increase in the content of trace and heavy metals and the level of gamma-emitters in the mine spoil and crop produce was observed, but well within the permissible limits. The residual effect of LFA on succeeding crops was also encouraging in terms of eco-friendliness. Beyond 20 t/ha of LFA, the crop yield decreased significantly (p < 0.05), as a result of the formation of hardpan in the mine spoil and possibly the higher concentration of soluble salts in the LFA. However, the adverse effects of soluble salts were annulled progressively during the cultivation of succeeding crops. A plausible mechanism for the improved fertility of mine spoil and the carryover or uptake of toxic trace and heavy metals and gamma-emitters in mine spoil and crop produce is also discussed.

Agriculture↗
PubMed1999

Studies on p53 immunolocalisation in breast cancer and its prognostic significance.

Immunocytochemical localisation of mutant p53 in breast tumours serves as a potential prognostic molecular marker. In order to study the expression of p53 protein in breast cancer which constitutes the second most common malignancy in the South Indian female population, MAb CIBCVMC12 has been generated against human p53 protein isolated and purified from bacterial cell lysate of E.coli carrying the plasmid T 7-7 Hup53 grown in Luria broth to induce the expression of p53. The positive clones selected by ELISA were found to exhibit strong staining of nuclear p53 in both fresh and archival paraffin embedded breast tumour tissue sections. Commercial MAb D 07 against p53 was used as control. In immunoprecipitation, this MAb of IgG2b isotype was found to bind specifically to a protein of 53 kD. Immuno cyto chemical assay of normal, benign and malignant breast tissues of different histological types revealed that the majority of tumour cells were strong positive in the case of infiltrating ductal and lobular carcinomas, the staining being less intense for in situ carcinoma. The test for normal and benign tissues was negative. The staining patterns were comparable with those of control antibody. These results suggest that the MAb generated is specific to p53. The p53 protein expression was compared with the estrogen receptor (ER) status for 50 breast tumours which revealed that 38% of these were p53 positive and of these two were ER+. Among the p53 negative tumours, 48% were found to be ER+. A comparison of the p53 expression for 100 breast cancer patients indicated that 57% of the tumours were p53 negative and these patients had a longer overall 5 year survival rate and recurrent free interval which is statistically very significant. These results might suggest that p53 positive tumours are more aggressive biologically with poor prognosis.

Antibodies, Monoclonal↗
PubMed1987

Benign squamous papillomatosis: case report.

Squamous papillae in the vestibule are common. They were once considered to be normal variants of female anatomy, but reports of the viral aetiology of such lesions are emerging. When they are symptomatic, squamous papillae can lead to problems in sexual relationships between healthy partners. Here we report a case that responded well to treatment.

Adult↗