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Enzyme kinetic parameters have been estimated using MATLAB software via the Wilkinson nonlinear regression technique. The MATLAB script file written to implement this technique is short and very straightforward. Several software tools are commercially available for this purpose, with many graphical user interface (GUI) features. A routine use of these packages might offer immediate satisfaction of interactive hands-on experience; but in some cases the researcher might wish to write his/her own code and compare the results for further confirmation. Today MATLAB is in use in almost all the schools and laboratories as a standard software tool. So this paper is aimed at helping enzyme researchers to make use of this powerful software for estimation of parameters. It enables the incorporation of the analytical steps behind parameter estimation in an easy-to-follow manner and furnishes better visualization.

BDE-85 is a congener of a class of flame-retardant compounds called polybrominated diphenyl ethers (PBDEs). Although there are some studies on other congeners of PBDEs, there are none on the toxicity potential of this penta-BDE member. This study, therefore, reports the oxidative status and sciatic nerve conduction properties following BDE-85 treatment in rodents. The oxidative stress markers, lipid hydroperoxides, and the activities of antioxidant enzymes, namely superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and catalase, in the exposed mice liver and brain tissues showed tissue-specific alterations following intraperitoneal injection of 0.25 mg/kg body weight of BDE-85 for 4 days. The results indicate a significant disruption in the oxidant/antioxidant equilibrium and setting in of oxidative stress. Isolated sciatic nerves of rats exposed to 5 µg/mL or 20 µg/mL of BDE-85 showed a significant reduction in nerve conduction velocity and compound action potential amplitudes, indicating physiological damage to the sciatic nerves.

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Brominated flame retardants (BFRs) are synthetic organobromide compounds which inhibit ignition and combustion processes. Because of their immense ability to retard fire and save life and property, they have been extensively used in many products such as TVs, computers, foam, plastics etc. The five major classes of BFRs are tetrabromobisphenol-A (TBBPA), hexabromocyclododecane (HBCD), pentabromodiphenyl ether, octabromodiphenyl ether, and decabromodiphenyl ether. The last three are also commonly called PBDEs. BDE-85 and BDE-209 are the two prominent congeners of PBDEs and this study reports the adverse effects of these congeners in rodents. Exposure of rat sciatic nerves to 5 μg/mL and 20 μg/mL of BDE-85 and BDE-209 respectively lead to significant, concentration dependent reduction in nerve conduction function. Glucose absorption in the rat intestinal segments exposed to 5 μg/mL of BDE-85 and BDE-209 was significantly reduced for both the compounds tested. Lastly, mice when exposed to 0.25 mg/kg body weight for four days showed a disruption in oxidant and antioxidant equilibrium. The tissues namely liver and brain have shown increase in the levels of lipid hydroperoxides indicating oxidative stress. Moreover, all the protective enzymes namely superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase, and glutathione S transferase (GST) have shown tissue specific alterations indicating the induction of damaging oxidative stress and setting in of lipid peroxidation in exposed animals. The results indicate monitoring of PBDEs in the environment is essential because levels as low as 5 μg/mL and 0.25 mg/kg body weight were able to cause damage to the functions of rodents.