Here, we exploit Chemical Reaction Network Theory (CRNT) to develop an efficient procedure for calculating invariants that are linear combinations of “”complexes”", or the monomials coming from mass action. We show how this procedure can be used in proving earlier results of Horn and Jackson and Selleck LXH254 of Shinar
and Feinberg for networks of deficiency at most one. We then apply our method to enzyme bifunctionality, including the bacterial EnvZ/OmpR osmolarity regulator and the mammalian 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase glycolytic regulator, whose networks have deficiencies up to four. We show that bifunctionality leads to different forms of concentration control that are robust to changes in initial conditions or total amounts. Finally, we outline a systematic procedure for using complex-linear invariants to analyse molecular networks of any deficiency. (C) 2012 Elsevier Ltd. All rights reserved.”
“Dopaminergic neurotransmission is an important factor in the pathogenesis of apathy. In addition, the contribution of genetic factors to the regulation of brain dopaminergic activity is widely
acknowledged. Therefore, we hypothesized that genes associated with brain dopaminergic BAY 63-2521 activity may have some effects on apathy. In the current study, we evaluated the association between four functional single-nucleotide polymorphisms (SNPs) in specific genes related to dopaminergic neurotransmission and apathy in a general population. Participants in the health examination at the
Shimane Institute of Health Science were recruited for this study (n = 963). Apathy was assessed using the Japanese version of the apathy scale. SNPs were genotyped using the TaqMan method. In our population, 22.1% had apathy. We confirmed that apathy was associated with decreased cognitive function and depressive state. A significant association was found between an SNP in the catechol-O-methyltransferase (COMT) gene (rs4680) encoding the low-activity Met allele and apathy. This relationship was still significant after adjustment for confounding factors. Our study indicates an association between rs4680, an SNP in the COMT gene, and lower risk of apathy. Considering the function of rs4680, the current study suggests the importance of selleck chemicals dopaminergic neurotransmission in the pathogenesis of apathy in a general population. (C) 2013 Elsevier Ireland Ltd. All rights reserved.”
“Lipid-bilayer membranes are formed by self-assembly processes. The molecular interactions within the bilayer and with the environment impart a unique trans-bilayer lateral pressure profile and provide a set of physical mechanisms for formation of lipid domains and laterally differentiated regions in the plane of the membrane. Results from a number of experimental and theoretical studies of model lipid bilayers are reviewed, emphasizing the significance of these fundamental physical properties for the structure and dynamics of biological membranes.