Effects Of Methyl Methacrylate Research Articles

Effects of methyl methacrylate on the excitability of the area postrema neurons in rats

ObjectivesThe aim of the present study is to demonstrate the effects of inhaled methyl methacrylate (MMA) on the excitability of neurons in the area postrema (AP). We also investigated the relation between vagal afferent inputs and responding cells in the AP. MethodsWe set up two groups of experimental animals, such as rats inhaling MMA and rats inhaling room air. To visualize the changes of AP neuron excitability after inhalation of MMA for 90 min, c-Fos protein expression was identified and quantified by immunohistochemical analysis. Some rats receiving ventral gastric branch vagotomy were also subjected to the abovementioned experiment. ResultsThe number of c-Fos-immunoreactive (Fos-ir) cells in the MMA group was more than six times greater than that of the control group (statistically significant, p < 0.01). In vagotomized rats inhaling MMA, markedly smaller number of Fos-ir cells was identified in the AP compared to that of rats inhaling MMA without vagotomy. ConclusionsThese results indicate that inhalation of MMA increases neuronal excitability in the AP, suggesting that vagal afferent inputs are involved in the induction mechanism of Fos-ir cells by MMA.

CHEMICALLY CHITOSAN MODIFIED WITH METHYL METHACRYLATE AND ITS EFFECT ON MECHANICAL AND THERMAL PROPERTIES OF POLYPROPYLENE COMPOSITES

Effects of methyl methacrylate on the properties of chitosan-filled polypropylene (PP) composites has been investigated. Mechanical and thermal properties of the composites were analyzed according to ASTM D 638-91, thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC). The results showed that tensile strength of PP composites decreased upon the addition of chitosan, while Young's modulus improved. At a similar filler loading, the treated PP/chitosan composites were found to have higher tensile strength and Young's modulus as compared with the untreated composites. Thermal analysis results showed that thermal stability and crystallinity of the treated composites were higher than the untreated ones. Scanning electron microscopy (SEM) and Fourier transforms infrared (FTIR) studies revealed less detached filler from matrix on tensile surface of the treated composites as an evidence of enhanced filler-matrix interfacial adhesion due to formation of ester-bridge between the chitosan and the methyl methacrylate.

Properties of UV-curable solvent-free pressure sensitive adhesive

In this study, the effects of methyl methacrylate (MMA), trimethylolpropane triacrylate (TMPTA), difunctional silicone urethane acrylate oligomer, and UV-dose on the adhesive properties of UV-curable pressure-sensitive adhesives (PSAs) were investigated, for further optimizing the adhesive properties to meet the requirements on high holding power and low peel strength. The results illustrated that increasing the MMA content decreased the peel strength and improved the holding power. The variation of TMPTA content from 1 to 10 wt% significantly enhanced the holding power from 1 h to above 120 h. The gel fraction increased with increasing TMPTA content. This increment was caused by the cross-linking of TMPTA after UV exposure. The peel strength of UV-curable PSAs was reduced to zero when oligomer content was more than 40 wt%, whereas the holding power was significantly enhanced from 5 h to above 120 h as the oligomer content increased up to 70 wt%. When the UV-dose increased, the peel strength decreased and the holding power increased. Therefore, UV-curable PSAs with very low peel strength and high holding power above 120 h were successfully synthesized and they possessed desirable features which could be fabricated to meet the specific requirements for industrial applications.

マクロファージ様細胞の分化に及ぼすメチルメタクリレートとジメチル-p-トルイジンの影響

マクロファージ様細胞の分化に及ぼすメチルメタクリレートとジメチル-p-トルイジンの影響

The effects of methylmethacrylate's hyperthermic polymerization on cerebral vascular permeability.

This study was undertaken to analyze the effects of significant hyperthermia (> 100 degrees C) associated with the polymerization of polymethlymethacrylate (PMM) on the permeability of the cerebral vasculature in rats. The method used to visualize the pial vasculature included the open pial window technique and epifluorescence microscopy. Results indicated that there is a significant increase in cerebral vascular permeability following in situ polymerization of PMM over the craniectomy site.

Effects of methyl methacrylate on non-protein thiols and drug metabolizing enzymes in rat liver and kidneys.

Male Wistar rats received methyl methacrylate monomer (MMA) i.p. in olive oil 1.0 g/kg body weight on 3 successive days. The weight of the livers and kidneys, and the body weights did not differ from their controls. On the fifth day after treatment, hepatic NADPH-cytochrome c reductase, 7-ethoxycoumarin 0-deethylase and the 2,5-diphenyloxazole hydroxylase exhibited maximal decreases in activity (25%, 58%, 36%, respectively) without any coincident effect on the total amount of cytochrome P-450 hemoprotein itself. One week later these activities had returned to control levels. The enzymatic changes in the kidneys were smaller in magnitude, and they were also reversed sooner. A single i.p. dose of MMA (2 g/kg body weight) caused elevation of serum alanine aminotransferase activity. A tenfold increase of the excretion rate of urinary thioethers was also discovered. The hepatic reduced glutathione (GSH) was depleted in 3 h to 20% and the GSSG to half of the value in controls. In kidneys, the GSH was decreased to 48% in 3 h before an apparent phase of overrecovery. At the end of the 24 h observation period, cytochrome P-450 concentrations were somewhat decreased in the liver. The GSH contents showed dose and time-dependent reversible decreases in isolated hepatocytes when incubated for 2 h in a medium containing MMA at the nominal concentrations of 0, 2, 5, or 10 mM. None of the treatments affected either the content of cytochrome P-450 or the viability of the liver cells.

Effects of Methyl Methacrylate on Liver Function in Patients undergoing Total Hip or Total Knee Replacement

Effects of Methyl Methacrylate on Liver Function in Patients undergoing Total Hip or Total Knee Replacement

Methacrylate and the liver: Herndon, J. H., Morrison, W. A. & Pilcher, F. J. (1980). Effects of methyl methacrylate on liver function in patients undergoing total hip or total knee replacement. Surgery Gynec. Obstet.150, 177

Methacrylate and the liver: Herndon, J. H., Morrison, W. A. & Pilcher, F. J. (1980). Effects of methyl methacrylate on liver function in patients undergoing total hip or total knee replacement. Surgery Gynec. Obstet.150, 177

Studies on preparation and stability of styrene-methyl methacrylate and styrene -methacrylic acid copolymer latices

Series of styrene-methyl methacrylate (SM) and styrene-methacrylic acid (SA) copolymer latices have been prepared by emulsion polymerization using polyoxyethylene nonyl phenyl ether as emulsifier and potassium persulphate as initiator. Trace carboxyl groups were detected both in polystyrene latex and styrene-methyl methacrylate copolymer latices. The stability and electrophoretic behaviour of these latices against barium chloride have been investigated. The values of the critical coagulation concentration (c. c. c.) increased with increasing methacrylic acid content for SA series latices, while they are almost independent of methyl methacrylate content for SM series latices. The effects of methyl methacrylate and methacrylic acid on the change in Hamaker constant were found to be almost identical. The difference inc. c. c. between SM and SA series latices seems to be due to the difference in electrical repulsion caused mainly by carboxyl groups on the surface.

Effects of Methylmethacrylate in Osteosynthesis

Effects of Methylmethacrylate in Osteosynthesis

The Cardiovascular Effects of Methylmethacrylate in Dogs

The Cardiovascular Effects of Methylmethacrylate in Dogs

Cardiovascular Effects of Methylmethacrylate

Cardiovascular Effects of Methylmethacrylate