In vivo contribution of Class III alcohol dehydrogenase (ADH3) to alcohol metabolism through activation by cytoplasmic solution hydrophobicity

AbstractAlcohol metabolism in vivo cannot be explained solely by the action of the classical alcohol dehydrogenase, Class I ADH (ADH1). Over the past three decades, attempts to identify the metabolizing enzymes responsible for the ADH1-independent pathway have focused on the microsomal ethanol oxidizing system (MEOS) and catalase, but have failed to clarify their roles in systemic alcohol metabolism. In this study, we used Adh3-null mutant mice to demonstrate that Class III ADH (ADH3), a ubiquitous enzyme of ancient origin, contributes to alcohol metabolism in vivo dose-dependently resulting in a diminution of acute alcohol intoxication. Although the ethanol oxidation activity of ADH3 in vitro is low due to its very high Km, it was found to exhibit a markedly enhanced catalytic efficiency (kcat/Km) toward ethanol when the solution hydrophobicity of the reaction medium was increased with a hydrophobic substance. Confocal laser scanning microscopy with Nile red as a hydrophobic probe revealed a cytoplasmic solution of mouse liver cells to be much more hydrophobic than the buffer solution used for in vitro experiments. So, the in vivo contribution of high-Km ADH3 to alcohol metabolism is likely to involve activation in a hydrophobic solution. Thus, the present study demonstrated that ADH3 plays an important role in systemic ethanol metabolism at higher levels of blood ethanol through activation by cytoplasmic solution hydrophobicity

CMV infection of trabecular meshwork cells

Purpose: Human cytomegalovirus (HCMV) infections can cause endotheliitis which is associated with an elevation of the intraocular pressure (IOP). However, the mechanism of the IOP elevation has not been determined. The purpose of this study was to determine whether HCMV strains which are capable of infecting corneal endothelial cells can also replicate, induce anti-viral responses, and can reorganize the actin cytoskeleton in trabecular meshwork cells. Study design: Experimental study design Methods: Cultured primary human trabecular meshwork cells (HTMCs) were infected with the Towne or TB40/E strains of HCMV. TB40/E is trophic for vascular endothelial and corneal endothelial cells. Real-time PCR, western blot, and fluorescent immunostaining have been used to determine whether HCMV-infected HTMCs will support the expression of viral mRNA and protein, allow viral replication, and elicit anti-viral host responses. We also determined whether lytic replication was present after an HCMV infection. Results: HCMV infection led to the expression of viral mRNA and proteins of IE1, glycoprotein B(gB), and pp65. TB40/E infection induced interferon-β, a sign of host anti-viral immune response and MCP-1. Together with the induction of the regulators of actin cytoskeleton, myosin phosphatase Rho interacting protein (MPRIP) and monocyte chemotactic protein-1 (MCP-1), TB40/E induced a high level of expression of viral proteins, including IE1, gB, and pp65 as well as actin stress fiber formation, and achieved pathogenically high viral titers. Conclusions: Human trabecular meshwork cells support the replication of endotheliotropic TB40/E strain of HCMV which indicates that this strain may have high virulence for trabecular meshwork

Direct observation of droplet formation in membrane emulsification

Direct observation of droplet formation in membrane emulsificatio

Left-right asymmetric expression of dpp in the mantle of gastropods correlates with asymmetric shell coiling

Background: Various shapes of gastropod shells have evolved ever since the Cambrian. Although theoretical analyses of morphogenesis exist, the molecular basis of shell development remains unclear. We compared expression patterns of the decapentaplegic (dpp) gene in the shell gland and mantle tissues at various developmental stages between coiled-shell and non-coiled-shell gastropods. Results: We analyzed the expression patterns of dpp for the two limpets Patella vulgata and Nipponacmea fuscoviridis, and for the dextral wild-type and sinistral mutant lineage of the pond snail Lymnaea stagnalis. The limpets had symmetric expression patterns of dpp throughout ontogeny, whereas in the pond snail, the results indicated asymmetric and mirror image patterns between the dextral and sinistral lineages. Conclusion: We hypothesize that Dpp induces mantle expansion, and the presence of a left/right asymmetric gradient of the Dpp protein causes the formation of a coiled shell. Our results provide a molecular explanation for shell, coiling including new insights into expression patterns in post-embryonic development, which should aid in understanding how various shell shapes are formed and have evolved in the gastropods.ArticleEVODEVO. 4:15 (2013)journal articl

Shirasu Porous Glass membrane emulsification: characterisation of membrane structure by high-resolution X-ray microtomography and microscopic observation of droplet formation in real time

The microstructure of ShirasuPorousGlass (SPG) membrane has been investigated using metallographic microscope and high-resolutionX-raymicrotomography (XMT) and the obtained results are compared with Hg-porosimetry data. The porosity in 600 cross sections analysed by high-resolution XMT was found to vary in a narrow range between 52.5 and 57.4% with a mean value of 55.1%. The membrane microstructure looks similar on SEM and XMT images with tortuous, interconnected cylindrical pores extending in all directions within the membrane. The formation of O/W and W/O/W emulsion droplets have been observed in real time using SPG or Microporous Glass (MPG) membrane disks with a mean pore size between 10.2 and 16.2 μm. The quality of video recordings was much better when membrane surface was finely polished with diamond paste, although it did not affect the droplet formation behaviour. The droplets formed at the same pore were highly monodispersed and detached in regular time intervals, but this time interval showed significant variations for different pores. The SDS-stabilised droplets were detached from the pores as soon as they were formed, due to strong electrostatic repulsions between anionic droplets and negatively charged SPG surface. The Tween 80-stabilised droplets were kept attached to the membrane surface after formation, before being pushed away by the next droplet formed at the same pore. Under the same conditions the SDS-stabilised droplets were smaller than the droplets stabilised by Tween 80

Bidirectional light-scattering image processing method for high-concentration jet sprays

In order to study the distributions of droplet size and volume density in high-concentration jet sprays, a new technique is developed, which combines the forward and backward light scattering method and an image processing method. A pulsed ruby laser is used as the light source. The Mie scattering theory is applied to the results obtained form image processing on the scattering photographs. The time history is obtained for the droplet size and volume density distributions, and the method is demonstrated by diesel fuel sprays under various injecting conditions. The validity of the technique is verified by a good agreement in the injected fuel volume distributions obtained by the present method and by injection rate measurements.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25819/1/0000382.pd