Micronutrients and Their Role in Oral Cancer: A Review.

Cancer is one of the leading causes of death across the world. Oral cancer is the sixth most common type of cancer in the world. The incidence of oral cancer increases with the increase in the consumption of carcinogens such as tobacco and alcohol as seen in south and southeast Asia. Oral cancer is seen to arise from pre-existing leukoplakia and oral submucous fibrosis. Antioxidants have been hypothesized to be chemopreventive agents for several cancers. Micronutrients such as zinc, copper and selenium, along with antioxidants are required for the production of various enzymes that help prevent DNA damage caused by free radicals.

Expression of Podoplanin in Different Grades of Oral Squamous Cell Carcinoma.

BACKGROUND: The expression of podoplanin is up-regulated in a number of different human cancers, including squamous cell carcinoma of the oral cavity and its relationship with tumor invasion raises the possibility that podoplanin expression could be used as a biomarker for diagnosis and prognosis. AIM: The aim of the present study is to evaluate the expression of podoplanin in different grades of squamous cell carcinoma (SCC) and to correlate the expression of podoplanin with relevant clinical features such as age, sex, site and associated habits. MATERIALS AND METHODS: Retrospective study was carried on formalin fixed, paraffin embedded blocks of oral SCC (OSCC) from the archives of Department of Oral and Maxillofacial Pathology, Vishnu Dental College, Bhimavaram. Thirty diagnosed cases were included, of which 10 were well-differentiated SCC (WDSCC) (n = 10), 10 moderately DSCC and 10 poorly DSCC. Demographics including age, sex, gender and associated habit history, were recorded. Immunohistochemical staining was done with podoplanin anti D2-40 antibody, for all the cases of OSCC and assessed qualitatively. The data obtained were tabulated and subjected to statistical analysis. RESULTS: In the present study, 27 cases of SCC showed podoplanin expression and remaining three cases showed no expression. The scoring criterion suggested by Yuan et al. was followed for semi-quantitative assessment. OSCC, seven cases presented weak expression (Immunoreactive score [IRS] 0-3), 15 presented moderate expression (IRS Score 4-7) and 5 presented high expression (IRS Score > 8). The assessment of podoplanin expression in the cytoplasm, the membrane and the cytoplasm and membrane (both) of tumor cells showed overall high positivity in the cytoplasmic followed by both and the membrane. CONCLUSION: Podoplanin could be a potent biomarker in assessing the cytoplasm/membrane staining of tumor cells. Furthermore, a high level of podoplanin expression is suggestive of high frequency of lymph node metastasis and immature status in the differentiation process of OSCC.

Sequential projection-based metacognitive learning in a radial basis function network for classification problems.

In this paper, we present a sequential projection-based metacognitive learning algorithm in a radial basis function network (PBL-McRBFN) for classification problems. The algorithm is inspired by human metacognitive learning principles and has two components: a cognitive component and a metacognitive component. The cognitive component is a single-hidden-layer radial basis function network with evolving architecture. The metacognitive component controls the learning process in the cognitive component by choosing the best learning strategy for the current sample and adapts the learning strategies by implementing self-regulation. In addition, sample overlapping conditions and past knowledge of the samples in the form of pseudosamples are used for proper initialization of new hidden neurons to minimize the misclassification. The parameter update strategy uses projection-based direct minimization of hinge loss error. The interaction of the cognitive component and the metacognitive component addresses the what-to-learn, when-to-learn, and how-to-learn human learning principles efficiently. The performance of the PBL-McRBFN is evaluated using a set of benchmark classification problems from the University of California Irvine machine learning repository. The statistical performance evaluation on these problems proves the superior performance of the PBL-McRBFN classifier over results reported in the literature. Also, we evaluate the performance of the proposed algorithm on a practical Alzheimer's disease detection problem. The performance results on open access series of imaging studies and Alzheimer's disease neuroimaging initiative datasets, which are obtained from different demographic regions, clearly show that PBL-McRBFN can handle a problem with change in distribution.

Evaluation of UV-induced superoxide radical generation potential of some common antibiotics.

Photosensitization reaction of drugs leading to the formation of reactive oxygen species (ROS) cause tissue injury causing damage to various cellular macromolecules. The aim of this study was to determine the superoxide anion (O2-) generation potential of commonly used antibiotics so that due precaution could be exercised to minimize their photosensitizing action and oxidative stress potential. The selected antibiotics were examined for their ability to produce (O2-) under sunlight and artificial UVA (320-400 nm) and UVB (290-320 nm). Lincomycin, cephalothin and erythromycin generated significant amount of O2- under various irradiation conditions. Superoxide dismutase (SOD), an enzymatic quencher of O2- inhibited O2- production in all drugs tested. The results suggest that due precaution are necessary to avoid ultraviolet radiation (UVR) after the intake of photoreactive drugs, especially in tropical and sub tropical countries.

Agricultural produce in the dry bed of the River Ganga in Kanpur, India--a new source of pesticide contamination in human diets.

Vegetables grown in the dry bed field of the River Ganga in Kanpur, an important industrial city of North India, were analysed for the pesticides hexachlorocyclohexane (HCH), dichlorodiphenyl trichloroethane (DDT), their isomers and metabolites at three different sites. Residues of both the pesticides were found in all the samples. Mean levels of 109.35, 136.76 and 145.93 microg HCH/kg and 6.64, 49.3 and 46.70 microg DDT/kg were found in the rural upstream, city and downstream industrial areas, respectively. The mean total HCH and DDT levels were within safe limits as per the Indian Standard but some samples had HCH levels above the WHO/FAO limit. The pesticide residue level in vegetables was several fold higher than their surrounding sandy soil and could pose health problems since these popular vegetables are consumed regularly by the population.

UVB-induced reduction in biomass and overall productivity of cyanobacteria.

Effect of middle wave ultraviolet radiation (UVB) was studied in three different species of cyanobacteria (Nostoc, Anabaena and Scytonema) by estimating their growth pattern, biomass yield, chlorophyll content, total starch and protein content. The results show that exposure of the cyanobacteria with UVB dose corresponding to an increase or decrease of 20% in its environmental flux will have drastic effects on biomass production, photosynthetic rate and nitrogen fixation. Cyanobacteria are primary sources of marine food web and an important biofertilizer; therefore, their protection from increasing threat of stratospheric ozone depletion will be necessary to maintain the ecological balance.