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Background and Objectives

A controversy developed between the benefits of energy drinks (EDs) versus the possible health threats since its revolution. Lack of information was a call to assess the effect of chronic consumption of Power Horse (PH) as one of the EDs, on the structure of pancreas and fundic mucosa of stomach in rats, and possible protective role of Omega-3.

Materials and Methods

Thirty two adult male albino rats were divided equally into 4 groups; control received group which only received a standard diet, Omega-3 group, PH group which given PH and PH plus Omega-3 group received both PH plus Omega-3 for 4 weeks. Biochemical assessment of blood glucose, serum insulin, gastrin, tumor necrosis factor alpha (TNF-α) and inducible nitric oxide synthetase (iNOS) was performed. The antioxidant activity and histopathological examination of both pancreatic tissue and fundic mucosa of stomach were assessed.

Results

Administration of PH significantly increased serum insulin and glucose levels while it significantly reduced serum gastrin level compared to control. PH also caused oxidants/antioxidants imbalance in both pancreas and fundic mucosa. The latter revealed degenerative changes and increased apoptosis which was evident by increased caspase-3 immunoexpression. Pancreas exhibited signs of β-cells overstimulation. Fundic mucosa showed reduced number of parietal cells, gastrin hormone expression compared to control group. Omega-3 administration could alleviate, to some extent, these changes. It significantly decreased TNF-α, iNOS and reduced glutathione (GSH) as well as significantly increasing superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities compared to the group which received PH alone.

Conclusion

Power Horse intake significantly injures islet cells, pancreatic acini as well as the glandular cells of the fundic mucosa. Omega-3 decreases these detrimental effects mostly through its antioxidant and anti-inflammatory action.  相似文献   
64.
Recently, studies have reported the use of Near Infrared Spectroscopy (NIRS) for developing Brain–Computer Interface (BCI) by applying online pattern classification of brain states from subject-specific fNIRS signals. The purpose of the present study was to develop and test a real-time method for subject-specific and subject-independent classification of multi-channel fNIRS signals using support-vector machines (SVM), so as to determine its feasibility as an online neurofeedback system. Towards this goal, we used left versus right hand movement execution and movement imagery as study paradigms in a series of experiments. In the first two experiments, activations in the motor cortex during movement execution and movement imagery were used to develop subject-dependent models that obtained high classification accuracies thereby indicating the robustness of our classification method. In the third experiment, a generalized classifier-model was developed from the first two experimental data, which was then applied for subject-independent neurofeedback training. Application of this method in new participants showed mean classification accuracy of 63% for movement imagery tasks and 80% for movement execution tasks. These results, and their corresponding offline analysis reported in this study demonstrate that SVM based real-time subject-independent classification of fNIRS signals is feasible. This method has important applications in the field of hemodynamic BCIs, and neuro-rehabilitation where patients can be trained to learn spatio-temporal patterns of healthy brain activity.  相似文献   
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Climate change is expected to alter precipitation patterns worldwide, which will affect streamflow in riverine ecosystems. It is vital to understand the impacts of projected flow variations, especially in tropical regions where the effects of climate change are expected to be one of the earliest to emerge. Space‐for‐time substitutions have been successful at predicting effects of climate change in terrestrial systems by using a spatial gradient to mimic the projected temporal change. However, concerns have been raised that the spatial variability in these models might not reflect the temporal variability. We utilized a well‐constrained rainfall gradient on Hawaii Island to determine (a) how predicted decreases in flow and increases in flow variability affect stream food resources and consumers and (b) if using a high temporal (monthly, four streams) or a high spatial (annual, eight streams) resolution sampling scheme would alter the results of a space‐for‐time substitution. Declines in benthic and suspended resource quantity (10‐ to 40‐fold) and quality (shift from macrophyte to leaf litter dominated) contributed to 35‐fold decreases in macroinvertebrate biomass with predicted changes in the magnitude and variability in the flow. Invertebrate composition switched from caddisflies and damselflies to taxa with faster turnover rates (mosquitoes, copepods). Changes in resource and consumer composition patterns were stronger with high temporal resolution sampling. However, trends and ranges of results did not differ between the two sampling regimes, indicating that a suitable, well‐constrained spatial gradient is an appropriate tool for examining temporal change. Our study is the first to investigate resource to community wide effects of climate change on tropical streams on a spatial and temporal scale. We determined that predicted flow alterations would decrease stream resource and consumer quantity and quality, which can alter stream function, as well as biomass and habitat for freshwater, marine, and terrestrial consumers dependent on these resources.  相似文献   
67.
Pheromone peptides are an important component of bacterial quorum‐sensing system. The pheromone peptide cOB1 (VAVLVLGA) of native commensal Enterococcus faecalis has also been identified as an antimicrobial peptide (AMP) and reported to kill the prototype clinical isolate strain of E. faecalis V583. In this study, the pheromone peptide cOB1 has shown to form amyloid‐like structures, a characteristic which is never reported for a pheromone peptide so far. With in silico analysis, the peptide was predicted to be highly amyloidogenic. Further, under experimental conditions, cOB1 formed aggregates displaying characteristics of amyloid structures such as bathochromic shift in Congo red absorbance, enhancement in thioflavin T fluorescence, and fibrillar morphology under transmission electron microscopy. This novel property of pheromone peptide cOB1 may have some direct effects on the binding of the pheromone to the receptor cells and subsequent conjugative transfer, making this observation more important for the therapeutics, dealing with the generation of virulent and multidrug‐resistant pathogenic strains.  相似文献   
68.
Phosphorylation of types III and IV intermediate filaments (IFs) is known to regulate their organization and function. Phosphorylation of the amino-terminal head domain sites on types III and IV IF proteins plays a key role in the assembly/disassembly of IF subunits into 10 nm filaments, and influences the phosphorylation of sites on the carboxyl-terminal tail domain. These phosphorylation events are largely under the control of second messenger-dependent protein kinases and provide the cells a mechanism to reorganize the IFs in response to the changes in second messenger levels. In mitotic cells, Cdk1, Rho kinase, PAK1 and Aurora-B kinase are believed to regulate vimentin and glial fibrillary acidic protein phosphorylation in a spatio-temporal manner. In neurons, the carboxyl-terminal tail domains of the NF-M and NF-H subunits of heteropolymeric neurofilaments (NFs) are highly phosphorylated by proline-directed protein kinases. The phosphorylation of carboxyl-terminal tail domains of NFs has been suspected to play roles in forming cross-bridges between NFs and microtubules, slowing axonal transport and promoting their integration into cytoskeleton lattice and, in doing so, to control axonal caliber and stabilize the axon. The role of IF phosphorylation in disease pathobiology is discussed.  相似文献   
69.
Normal Cdk5 activity, conferred mainly by association with its primary activator p35, is critical for normal function of the cell and must be tightly regulated. During neurotoxicity, p35 is cleaved to form p25, which becomes a potent and mislocalized hyperactivator of Cdk5, resulting in a deregulation of Cdk5 activity. p25 levels have been found to be elevated in Alzheimer's disease (AD) brain and overexpression of p25 in a transgenic mouse results in the formation of phosphorylated tau, neurofibrillary tangles and cognitive deficits that are pathological hallmarks of AD. p25/Cdk5 also hyperphosphorylates neurofilament proteins that constitute pathological hallmarks found in Parkinson's disease and amyotrophic lateral sclerosis. The selective targeting of p25/Cdk5 activity without affecting p35/Cdk5 activity has been unsuccessful. In this review we detail our recent studies of selective p25/Cdk5 inhibition without affecting p35/Cdk5 or mitotic Cdk activities. We found that a further truncation of p25 to yield a Cdk5 inhibitory peptide (CIP) can specifically inhibit p25/Cdk5 activity in transfected HEK cells and primary cortical neurons. CIP was able to reduce tau hyperphosphorylation and neuronal death induced caused by p25/Cdk5 and further studies with CIP may develop a specific Cdk5 inhibition strategy in the treatment of neurodegeneration.  相似文献   
70.
Phage 812 is a polyvalent phage with a very broad host range in the genus Staphylococcus, which makes it a suitable candidate for phage therapy of staphylococcal infections. This proteomic study, combining the results of both 1-DE and 2-DE followed by PMF, led to the identification of 24 virion proteins. Twenty new proteins, not yet identified by proteome analysis of closely related staphylococcal phages K and G1 were identified using this approach. Fifteen proteins were assigned unambiguously to the head-tail genome module; the remaining nine proteins are encoded by genes of the left or right arms of the phage genome. As expected, the most abundant proteins in the electrophoretic patterns are the major capsid protein, the major tail sheath protein and proteins identical to ORF 50 and ORF 95 of phage K, although their function is only putative. Identification of these 20 new proteins contributes substantially to a detailed characterization of phage virions, knowledge of which is necessary for rational phage therapy.  相似文献   
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