Films are stable with respect to dewetting as investigated with optical microscopy and atomic force microscopy. P(S-b-MDEGA-b-S) films with a thickness of 39 nm exhibit a phase transition of the lower critical solution temperature (LCST) type at 36.5 degrees C. The swelling and the thermoresponsive behavior of the films with respect to a sudden thermal stimulus are probed with in-situ www.selleckchem.com/screening-libraries.html neutron reflectivity. In undersaturated
water vapor swelling proceeds without thickness increase. The thermoresponse proceeds in three steps: First, the film rejects water as the temperature is above LCST. Next, it stays constant for 600 s, before the collapsed film takes up water again. With ATR-FTIR measurements, changes of bound water in the film caused by different thermal stimuli are studied. Hydrogen bonds only form between C=O and water in the swollen film. Above the LCST most hydrogen bonds with water are broken, but some amount of bound water remains inside the film in agreement with the neutron reflectivity data. Grazing-incidence small-angle X-ray scattering (GISAXS) shows that the inner lateral structure is not significantly influenced by the different thermal stimuli.”
“Myasthenia gravis (MG) is an autoimmune disease caused by an immunological response against the acetylcholine
receptor (AChR) at the neuromuscular junction. Anti-AChR antibodies induce degradation buy MG-132 of the receptor, activation of complement cascade and destruction of the post-synaptic membrane, resulting in a functional reduction of AChR availability. The pathophysiological role of autoantibodies Lonafarnib mw (auto-Abs) and T helper lymphocytes has been studied in the experimental autoimmune MG (EAMG) models. EAMG models have been employed to investigate the factors involved in the development
of MG and to suggest new therapies aimed to preventing or modulating the ongoing disease. EAMG can be induced in susceptible mouse and rat strains, which develop clinical symptoms such as muscular weakness and fatigability, mimicking the human disease. Two major types of EAMG can be induced, passive and active EAMG. Passive transfer MG models, involving the injection of auto-Abs, are helpful for studying the role of complement molecules and their regulatory proteins, which can prevent neuromuscular junction degradation. Active models, induced by immunization, are employed for the analysis of antigen-specific immune responses and their modulation in order to improve disease progression. In this review, we will concentrate on the main pathogenic mechanisms of MG, focusing on recent findings on EAMG experimental models.”
“A simple, accurate, and inexpensive high-performance thin-layer chromatography (HPTLC) method has been established for analysis of saccharin in foodstuffs, for example cola drinks, lemon juices, betel nut powder, mouth fresheners, ice candy, and tabletop sweeteners.