Melatonin Successfully Rescues the Hippocampal Molecular Machinery and Enhances Anti-oxidative Activity Following Early-Life Sleep Deprivation Injury

Early-life sleep deprivation (ESD) is a serious condition with severe cognitive sequelae. Considering hippocampus plays an essential role in cognitive regulation, the present study aims to determine whether melatonin, a neuroendocrine beard with significant anti-oxidative activity, would greatly depress the hippocampal oxidative stress, improves the molecular machinery, and consequently exerts the neuro-protective effects following ESD. Male weanling Wistar rats (postnatal day 21) were subjected to ESD for three weeks. During this period, the animals were administered normal saline or melatonin (10 mg/kg) via intraperitoneal injection between 09:00 and 09:30 daily. After three cycles of ESD, the animals were kept under normal sleep/wake cycle until they reached adulthood and were sacrificed. The results indicated that ESD causes long-term effects, such as impairment of ionic distribution, interruption of the expressions of neurotransmitters and receptors, decreases in the levels of several antioxidant enzymes, and impairment of several signaling pathways, which contribute to neuronal death in hippocampal regions. Melatonin administration during ESD prevented these effects. Quantitative evaluation of cells also revealed a higher number of neurons in the melatonin-treated animals when compared with the saline-treated animals. As the hippocampus is critical to cognitive activity, preserving or even improving the hippocampal molecular machinery by melatonin during ESD not only helps us to better understand the underlying mechanisms of ESD-induced neuronal dysfunction, but also the therapeutic use of melatonin to counteract ESD-induced neuronal deficiency.

Electroviscous Effects in Stationary Solid Phase Suspensions

Flowing through porous media is a matter of interest in different research fields such as medicine, engineering and science. The spontaneous appearance of ionic distribution at the solid liquid interface gives place to a reduction in the flow rate, which is generally named electroviscous effect. However, this should be differentiated in two more specific effects, the primary effect due to the distortion of ionic clouds, and the secondary effect due to the overlapping of ionic clouds. Theoretical and experimental works have not always been clearly conducted in order to separate both effects. Instead, they have been globally grouped. The purpose of this review is to revise theoretical and experimental bibliography on the electroviscous effect in stationary solid phase suspensions (porous plugs, membranes, microchannels, capillaries). The main conclusions of this brief revision are: (i) when ionic clouds are relatively small, it is possible to accept that only the primary effect is the cause for the apparent increase of the viscosity of the liquid phase when it is forced to flow relative to the stationary solid phase; (ii) although theory predicts a maximum for the variation of the overall electroviscous effect vs the relative size of the ionic cloud, it has been experimentally observed but not properly reasoned that its existence depends on the salt type; and (iii) it is necessary to justify why, if the fluid is non-Newtonian, electrokinetic parameters dominate the characteristics of the flow due to high pressure gradients, but the rheological parameters are more decisive when the flow is generated by low pressure gradients.

Spice crops tolerant to salinity and alkalinity

Tolerance and yield of a crop are complex genetic traits, which are difficult to maintain simultaneously since salt stress may occur as a catastrophic agent, be imposed continuously or intermittently or become gradually more severe. Salinity and alkalinity stress have a major impact on spices in the form of their growth, development and yield.Adverse effects of salinity might be due to ion cytotoxicity and osmatic stress, which disrupt homeostasis in water potential and ionic distribution due to disordering in cohesions of membrane lipids and proteins and influence various physiological and biochemical processes. To review the tolerance of spices to salinity and alkalinity, the present paper collates the existing experimental data sets, establishing the salt tolerance limits under saline or alkali environment either in soil root zone or which is created due to the application of saline or alkali irrigation water for crop production. Studies show that the salt affected areas and saline irrigation water can be utilized satisfactorily to raise forest and fruit tree species, forage grasses, conventional and non-conventional crops, oil seed crops, spice crops of high economic value, petro-crops and flower plants.

Folding dynamics of Aβ42 monomer at pH 4.0–7.5 with and without physiological salt conditions – does the β1 or β2 region fold first?

The seeding region of Aβ42 monomer is jointly affected by the solution acidity, ionic distribution of the salt, and charged residues.

Matrix Discriminant Analysis Evidenced Surface-Lithium as an Important Factor to Increase the Hydrolytic Saccharification of Sugarcane Bagasse

Statistical evidence pointing to the very soft change in the ionic composition on the surface of the sugar cane bagasse is crucial to improve yields of sugars by hydrolytic saccharification. Removal of Li+ by pretreatments exposing -OH sites was the most important factor related to the increase of saccharification yields using enzyme cocktails. Steam Explosion and Microwave:H2SO4 pretreatments produced unrelated structural changes, but similar ionic distribution patterns. Both increased the saccharification yield 1.74-fold. NaOH produced structural changes related to Steam Explosion, but released surface-bounded Li+ obtaining 2.04-fold more reducing sugars than the control. In turn, the higher amounts in relative concentration and periodic structures of Li+ on the surface observed in the control or after the pretreatment with Ethanol:DMSO:Ammonium Oxalate, blocked -OH and O− available for ionic sputtering. These changes correlated to 1.90-fold decrease in saccharification yields. Li+ was an activator in solution, but its presence and distribution pattern on the substrate was prejudicial to the saccharification. Apparently, it acts as a phase-dependent modulator of enzyme activity. Therefore, no correlations were found between structural changes and the efficiency of the enzymatic cocktail used. However, there were correlations between the Li+ distribution patterns and the enzymatic activities that should to be shown.

A General Theory of Electrochemistry

A new and uniform electro-chemical theory is presented, from whichfundamental laws and properties describing an electrode/electrolyte system are derived.The theory accurately models the electric field and the ionic distribution in the immediate vicinity of the electrode, which allows fundamentalproperties of the electrode/electrolyte system to be derived.To demonstrate the general validity of the theory the well-known But-ler/Volmer and Nernst’s equations are derived.The theory also permits the accurate modeling of dynamic, or non-equilibrium properties, like the voltage variation with time from the mo-ment an electrode is dipped into an inert electrolyte.To assess the accuracy of the modeling, experiments were carried outwhere a zinc electrode was dipped into a sodium sulfate electrolyte. The electrode voltage was measured over a 5 to 640 sec time span and would typically be within 5 mV of the predicted value.The electrode voltage was also derived from initial contact with anelectrolyte containing the electrode ions until equilibrium was fully established - ending up in agreement with the predictions of Nernst’s equationfor a range of concentrations.The theory also permitted the complex impedance of the electrode/electrolyteinterface reaction to be derived.Comparison with experimental data was carried out, where the complex impedance of a copper electrode in contact with nine different copper sulfate/hydrogen sulfateelectrolytes was measured. The fit with the theory was typically within2% over the entire 0.07 to 2400 Hz measurement range.The best fit with the experimental data allowed in turn the exchangecurrent and the extent of the electric field distribution to be determinedas functions of concentration.