With the growing use of wireless devices in almost all day-to-day activities, exposure to radio-frequency radiation has become an immediate health concern. It is imperative that the effects of such radiation not only on humans, but also on other organisms be well understood. In particular, it is critical to understand if RF radiation has any bearing on the gene expression during embryonic development, as this is a crucial and delicate phase for any organism. Owing to possible effects that RF radiation may have on gene expression, it is essential to explore the carcinogenic or teratogenic properties that it may show. This study observed the effects of RF radiation emitted from a cellular telephone on the embryonic development of zebra fish. The expression of the gene shha plays a key role in the early development of the fish. This gene has homologs in humans as well as in other model organisms. Additionally, several biomarkers indicative of cell stress were examined: including lactate dehydrogenase (LDH), superoxide dismutase (SOD), and lipid peroxidation (LPO). Results show a significant decrease in the expression of shha, a significant decrease in LDH activity. There was no significant increase in SOD and LPO activity. No morphological abnormalities were observed in the developing embryos. At present, these results indicate that exposure to cell phone radiation may have a suppressive effect on expression of shha in D. rerio, though such exposure does not appear to cause morphological detriments. More trials are underway to corroborate these results.
Biochemical pathways characterize various biochemical reaction schemes that involve a set of species and the
manner in which they are connected. Determination of schematics that represent these pathways is an important
task in understanding metabolism and signal transduction. Examples of these Pathways are: DNA and protein
synthesis, and production of several macro-molecules essential for cell survival. A sustained feedback mechanism arises in gene expression and production of mRNA that lead to protein synthesis if the protein so synthesized serves as a transcription factor and becomes a repressor of the gene expression. The cellular regulations are carried out through biochemical networks consisting of reactions and regulatory proteins.
Systems biology is a relatively new area that attempts to describe the biochemical pathways analytically and
develop reliable mathematical models for the pathways. A complete understanding of chemical reaction kinetics
is prohibitively hard thanks to the nonlinear and highly complex mechanisms that regulate protein formation,
but attempting to numerically solve some of the governing differential equations seems to offer significant insight about their biochemical picture. To validate these models, one can perform simple experiments in the lab.
This paper introduces fundamental ideas in biochemical signaling and attempts to take first steps into the understanding of biochemical oscillations. Initially, the two-pool model of calcium is used to describe the
dynamics behind the oscillations. Later we present some elementary results showing biochemical oscillations
arising from solving differential equations of Elowitz and Leibler using MATLAB software.
Polybrominated Diphenyl Ethers (PBDEs) are flame retardants widely used in many commercial products, including building materials, electronics, furnishings, motor vehicles, airplanes, plastics, polyurethane foams, and textiles. Although the specific toxic action of these chemicals is not clear, it is reported that they can cause serious damage to the nervous, reproductive, and endocrine systems. These chemicals are branded as “probable carcinogens” by Environmental Protection Agency (EPA). Therefore, this study is taken up to investigate the expression of genes namely, TP-53, RAD1, CRADD, and ATM, which are involved in apoptosis, DNA repair and cell cycle regulation. For this study human umbilical vein endothelial cells (HUVEC) are exposed to 5 μM of BDE-85 (a penta-BDE) and BDE-209 (deca-BDE). The results of this report reveal significant alteration in all the genes under investigation in BDE-85 and BDE-209 exposed cells. The BDE-85 induced responses are significantly more than BDE-209. These results emphasize the congener specific action of PBDEs on the expression of genes relevant to DNA repair and cell division of HUVEC cells.
Radio wave frequency (RF) radiation emitted from cellular telephones has become increasingly ubiquitous as a result of the popularity of these phones. With the increasing and unavoidable exposure to RF radiation a reality, it is imperative that the effects of such radiation on living tissue be well understood. In particular, it is critical to understand any effects that RF radiation may have as a carcinogen and on embryonic development, as pregnant women are not exempt from such exposure. As a model organism, zebrafish (Danio rerio) have been studied extensively, and their value in studies of gene expression cannot be overstated. This study observed the effects of RF radiation on the embryonic development of zebrafish. The expression of two genes, shha and hoxb9a, that are key to the early development of the fish was examined. Both genes have homologs in humans as well as in other model organisms. Preliminary results suggest that exposure to cell phone radiation might have an effect on the expression of shha in zebrafish embryos, causing under expression. More trials are necessary to validate these results.
Lake Erie is one of the five great lakes of North America. It is the shallowest, the warmest, and the most biologically
productive of the Great Lakes producing more fish than all of the other four lakes combined. It is also a source of
drinking water for 11 million people and a recreational asset. On the flipside, it is also very vulnerable and troubled
with environmental challenges because it has the smallest water volume, but the greatest pressures from the human
settlement. One of the many issues faced by the Lake is pollution. It receives larger loads of many pollutants than
any other Great Lake. Even with the best pollution controls many pesticides and organohalogens continue to enter
the lake.
Polybrominated diphenyl ethers (PBDEs) are a class of flame-retardants that have been used in a variety of
consumer products since the 1970s. They are added to many commercial and household products such as computers,
foam mattresses, carpets, etc. Being largely non-polar and chemically stable, these chemicals are extremely
lipophilic and resist degradation in the environment, thus giving them a high affinity for their bioaccumulation. Due
to these properties PBDEs have become ubiquitous environmental contaminants. These compounds are reported to
be endocrine disruptors and could cause oxidative damage. This report presents the sample preparation protocol, the
GC-MS analysis of PBDEs in Lake Erie sediment samples.
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.
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