16 research outputs found
Oxidative stress and superoxide dismutase activity in brain of rats fed with diet containing permethrin
Many pesticides have been reported to cause a lot of health problems in
workers, users and non-target organisms in the environment. Permethrin
containing insect pesticide has been reported to be toxic to non-target
organisms. However, the underlying mechanism involved in the toxicity
is not well understood. The present study was envisaged to investigate
the possible role of oxidative stress in permethrin neurotoxicity and
to evaluate the protective effect of superoxide dismutase (SOD)
activity in brain homogenates of Wistar rats. Oxidative stress measured
as thiobarbituric acid reacting substances (TBARS) was found to
significantly increase (p < 0.05) in all the experimental groups
compared with their parallel controls. Concomitantly, the activity of
SOD was found to decrease or increase significantly (p < 0.05) in
the experimental groups compared with their controls. Our result also
showed that activity of SOD was aged and concentration dependent.
Hence, the newly weaned rats appear to be more susceptible to the
pesticide contaminated diet because the SOD activity decreased more in
the brain homogenates compared with the middle aged rats or aged rats.
Observed aggressive behaviour was noticed in the pesticide exposed
rats, hence a possible neurobehavioral effect. The result demonstrated
that the pyrethroid insect powder exerts its toxic effect by promoting
oxidative stress in the brain and this may affect normal brain
functioning and growth
Oxidative stress and superoxide dismutase activity in brain of rats fed with diet containing permethrin
Many pesticides have been reported to cause a lot of health problems in
workers, users and non-target organisms in the environment. Permethrin
containing insect pesticide has been reported to be toxic to non-target
organisms. However, the underlying mechanism involved in the toxicity
is not well understood. The present study was envisaged to investigate
the possible role of oxidative stress in permethrin neurotoxicity and
to evaluate the protective effect of superoxide dismutase (SOD)
activity in brain homogenates of Wistar rats. Oxidative stress measured
as thiobarbituric acid reacting substances (TBARS) was found to
significantly increase (p < 0.05) in all the experimental groups
compared with their parallel controls. Concomitantly, the activity of
SOD was found to decrease or increase significantly (p < 0.05) in
the experimental groups compared with their controls. Our result also
showed that activity of SOD was aged and concentration dependent.
Hence, the newly weaned rats appear to be more susceptible to the
pesticide contaminated diet because the SOD activity decreased more in
the brain homogenates compared with the middle aged rats or aged rats.
Observed aggressive behaviour was noticed in the pesticide exposed
rats, hence a possible neurobehavioral effect. The result demonstrated
that the pyrethroid insect powder exerts its toxic effect by promoting
oxidative stress in the brain and this may affect normal brain
functioning and growth
Heavy metal contamination of green leafy vegetable garden in Itam road construction site in Uyo, Nigeria. Research journal of environmental and earth sciences 4(4
Abstract: Human exposure to heavy metals is a subject of public health concern that have attracted the attention of researchers, health and nutrition experts all over the world. Green Leafy Vegetables (GLVs) are important part of diets in the South-South Region of Nigeria. Consumption of vegetables exposed to heavy metals contamination may lead to serious health complications. In this investigation, we estimated the concentrations of some heavy metals (Pb, Hg, Al, Cd, Fe and Zn) in GLVs harvested from vegetable gardens in the residential areas along Itam road construction site, Uyo, Nigeria. The results showed that Pb, Hg, Al and Cd concentrations were significantly high (p<0.05) in all exposed GLV samples than the control but Teliferia occidentalis had higher values of heavy metals than Talinium triangulare. However, zinc and iron levels in the GLV exposed samples were not significantly (p>0.05) higher than the control. Our findings showed that heavy metal contamination of edible vegetable is high at road construction sites and may impact negatively on the health of human and animals living in such environment. We suggest that health impact assessment be carried out at construction sites in order to suggest necessary measure that can alleviate the effects of such environmental contaminants
Application of robust model validation using SOSTOOLS to the study of G-Protein signalling in yeast
Two major methodological challenges in modeling biological systems are model (in)validation and parameter estimation. The traditional approach is to fit the model parameters to data. An alternative approach pioneered by Packard, Frenklach, Seiler and colleagues (Frenklach et al., 2002) defines the range of parameter values that is consistent with the data while taking into account parametric and data uncertainty. If an invalidation certificate is found, the feasible parameter space is proved empty; otherwise, attempts to describe the feasible parameter space are carried out. We refer to this methodology as Robust Model Validation (RMV). Here we perform RMV using sum of squares (SOS) programs implemented by the MATLAB toolbox SOSTOOLS (Prajna et al., 2002). The principal advantage of SOS over conventional semidefinite programming (SDP) techniques such as the Sprocedure is the possibility of using higher-order multipliers to obtain tighter parameter bounds. We applied SOSTOOLS to a simple model of the yeast heterotrimeric G-protein cycle. We were able to invalidate the model based on real experimental data. Furthermore, using synthetic data that did not invalidate the model, we explored different techniques for representing the feasible parameter space