The Effects of Different Dose of Chronic Ritalin on the Brain of Prepubertal Female Balb/C Mice

Background Methylphenidate (MPH) is commonly prescribed for children who have been diagnosed with attention deficit hyperactivity disorder (ADHD); however, the action mechanisms of methylphenidate have not been fully elucidated. Studies have shown a relationship between apoptosis signaling pathways and psychiatric disorders, as well as therapeutic targets for such disorders. So, we examined the effects of chronic methylphenidate administration on the brain of mice. Materials and Methods Animals were administered MPH at doses of 2, 5 and 10 mg/kg for 60 days.  At the age of three months and in estrous phase, brian tissues were removed and washed in cold phosphate-buffered saline and some of them were frozen at -80oC for Western blot analysis. We measured the levels of pro-apoptotic protein, Bax and anti-apoptoticprotein, Bcl-2, in the brain of neonate female Balb/c mice. The rest of the brains were fixed in formalin (10% phosphate-buffered, pH = 7.4). Then samples were embedded in paraffin according to routine histologic procedures. Results: Our results showed that MPH with a dose of 10 mg/kg causes a considerable increase in the level of the Bax protein as compared with other groups. In contrast, in the partial cortex of female mice under treatment with high dose of MPH (10 mg/kg) could less Bcl2 levels as compared with 5 mg/kg MPH. However, 5 mg/kg MPH have a significant effect on Bcl2 levels compare with each of mentioned doses (

Investigation of kinetic properties of hydrolyzed polyacrylamide crosslinked by transient metal ligand

669-672The aim of this study was to investigate the kinetic properties of hydrolyzed polyacrylamide gel. The hydrolyzed polyacrylamide was synthesized by free radical mechanism. The optimum molecular weight for the gel preparation was then obtained after examination of various factors such as average molecular weight, initiator concentration and reaction time in the gelation process. The main interaction which creates supramolecular gel is metal ligand coordination between carboxylate groups and chromium ions, and amide groups. These bonds were confirmed by FTIR and UV-Visible spectra techniques. Furthermore, the XRD showed crystalline structure in the gel

Stability of Silica Nanoparticle Dispersion in Brine Solution: An Experimental Study

Nanotechnology has various applications in oil and gas industry such as enhanced oil recovery (EOR). The main challenge in using nanoparticles in EOR processes is their stability in harsh conditions such as high temperature, high pressure, and intermediate to high salinity. However, most of the recent experimental works have been performed under unrealistic conditions such as the use of distilled water as the injected fluid and room temperature. The main objective of this work is to study the effect of these factors on the stability of nanoparticle dispersions through several methods such as direct observation, optical absorption measurement, and nanoparticle effective diameter in different periods of time. The critical salt concentration (CSC) was determined for two kinds of monovalent electrolytes in various particle concentrations and temperatures. The results have shown that CSC for potassium chloride (KCl) is less than sodium chloride (NaCl) and it decreases as nanoparticle concentration and temperature increase. Moreover, the influence of two types of surfactants on the stability of silica dispersions was studied and the results revealed that an anionic surfactant increases the CSC, while a nonionic surfactant leads to the instability of dispersion even at low electrolyte concentrations