Three dihydroxy-4-methylcoumarin (DHMC) derivatives, namely 7,8-DHMC, 6,7-DHMC and 5,7-DHMC alone and complexed with Fe(III) and ADP have been tested for their antioxidative potential. Chemical speciation studies and formation constants reveal the formation of strong DHMC-Fe-ADP (1:1:1) ternary complex. In vitro studies were done for their antioxidative property by scavenging the superoxide radicals (O2*-) generated by xanthine + xanthine oxidase (XO) reaction. The IC50 values for 7,8-DHMC, 6,7-DHMC and 5,7-DHMC and their ternary complexes with Fe(III)-ADP worked out to be 34.0 microM, 62.0 microM, 8.80 mM and 10.5, 11.5 and 148.5 microM, respectively. The results indicate that O2*- scavenging potential of all the three DHMCs increased significantly after forming the ternary complex with Fe(III) and ADP. The structure activity relationship studies suggest that the introduction of hydroxyl group at 7th and 8th positions in the coumarins, irrespective of Fe(III)-ADP complexation, increases the antioxidative efficacy. No change in uric acid production in the reactions done for all studies further reveals that the coumarin derivatives and their complexes were the only causative factors for O2*- scavenging and not the suppression of the enzyme, xanthine oxidase.

Previously, we have reported that aurintricarboxylic acid (ATA) is one of the most potent inhibitors of the DNA binding of transcription factor NF-kappaB. We now report the NF-kappaB-DNA binding inhibitory activity of ATA analogues. An electrophoretic mobility shift assay has shown that bromopyrogallol red (BPR) is the most effective inhibitor of NF-kappaB-DNA binding among the studied analogues. The molecular modeling studies showed that BPR makes a strong network of hydrogen bonds with the DNA-binding region of the p50 subunit of NF-kappaB and has electronegative potential on its peripheral surface. Because zinc has been reported to influence the DNA binding of NF-kappaB, the interaction of these analogues with zinc was studied. Chemical speciation and formation-constant studies showed that BPR forms the most stable 1:1 complex with zinc. BPR has also been found to be the most potent antioxidant among the studied analogues.

Background. The aim of present study is to observe the association between the levels of ankle-brachial index (ABI) and cardiovascular risk factors among people with type 2 diabetes mellitus in north India. A cross-sectional study was carried out at a centre for heart and diabetic clinic in the state of Punjab on 1121 subjects (671 males and 450 females) with type 2 diabetes mellitus. History of symptoms related to cardiovascular diseases was noted, and blood pressure and anthropometric measurements were recorded. Ankle-brachial index (ABI) was measured using ultrasonic Doppler flow detector. Subjects with ABI ≤0.9 and ≥1.30 were classified as having low and high ABI, respectively. Females had a higher BMI and brachial-ankle pulse wave velocity (P < 0.001). Whereas, males had higher diastolic blood pressure and duration of type 2 diabetes mellitus. The differences of systolic blood pressure and ankle-brachial index were not found significant between the sexes. The prevalence of low ABI (<0.9) was 4.47% in men and 4.67% in women and high ABI (≥1.30) was prevalent in 14% of men and 10.45% of women. Age, BMI, baPWV, and blood pressures were significantly associated with ABI value in both sexes. The results suggested that the ABI might be used as a strong indicator for cardiovascular risk factors in type 2 diabetic subjects.

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An analytical model of the above-threshold characteristics of a small-geometry poly-silicon thin film transistor considering the grain boundary effect on the turn-on behaviour is proposed. Small geometry effects are also incorporated to develop an accurate expression for the threshold voltage and the current-voltage (I -V ) characteristics in the turn-on region. Further, the channel length dependent threshold voltage proposed shows good agreement with experimental data and the I -V characteristics with channel dimensions 2 and 0.5 µm are in excellent agreement with experimental results confirming the validity of this model.

A model that characterizes the subthreshold regime and the threshold voltage of a short-channel polycrystalline silicon thin-film transistor (poly-Si TFT) is developed and supported experimentally. The subthreshold variations with gate and drain voltages are reported and a stronger drain voltage dependence is observed. The subthreshold swing is calculated and its variation with channel length and doping concentration is studied. The results are compared with the available experimental data and a good match is found. The temperature dependence of subthreshold swing and drain current is also shown. The channel length dependent proposed threshold voltage shows excellent agreement with experimental data.

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Ameloblastoma occurs in a wide variety of forms. Various forms of ameloblastomas have various treatment modalities ranging from a conservative approach to surgical resection with reconstruction. We report a case of unicystic ameloblastoma with mural proliferation in a 17-year-old girl, who presented with a swelling in the lower left jaw associated with dull aching pain and was managed initially by a conservative approach followed by surgical enucleation on recurrence.