Regulation of intermediate filament organization during cytokinesis: possible roles of Rho-associated kinase

Intermediate filaments (IFs), which form the structural framework of cytoskeleton, have been found to be dramatically reorganized during mitosis. Some protein kinases activated in mitosis are thought to control spatial and temporal IF reorganization through phosphorylation of IF proteins. Rho-associated kinase (Rho-kinase), one of the putative targets of the small GTPase Rho, does phosphorylate IF proteins, specifically at the cleavage furrow during cytokinesis. This cleavage furrow-specific phosphorylation plays an important role in the local IF breakdown and efficient separation of IF networks. Recent studies on Rho signaling pathways have introduced new models about the molecular mechanism of rearrangements of cytoskeletons including IFs during cytokinesis.     

Discrete choice experiment of smoking cessation behaviour in Japan

Background

In spite of gradual increases in tobacco price and the introduction of laws supporting various anti‐tobacco measures, the proportion of smokers in Japan''s population is still higher than in other developed nations.

Objective

To understand what information and individual characteristics drive smokers to attempt to quit smoking. These determinants will help to realise effective tobacco control policy as a base for understanding of cessation behaviour.

Method

Discrete choice experiments on a total of 616 respondents registered at a consumer monitoring investigative company.

Results

The effect of price is greater on smokers with lower nicotine dependence. For smokers of moderate and low dependency, short term health risks and health risks caused by passive smoking have a strong impact, though the existence of penalties and long term health risks have little influence on smokers'' decisions to quit. For highly dependent smokers, non‐price attributes have little impact. Furthermore, the effects of age, sex and knowledge are also not uniform in accounting for smoking cessation.

Conclusion

Determinants of smoking cessation vary among levels of nicotine dependency. Therefore, how and what information is provided needs to be carefully considered when counselling smokers to help them to quit.     

Photoinduced electron transfer and hole migration along copolymer of vinylbenzenepyrrolidinofullerene[60] and N-vinylcarbazole

Photoinduced electron-transfer and hole-migration processes for newly prepared copolymers of C60 and N-vinylcarbazole (VCz) with the several compositions have been investigated using time-resolved fluorescence and absorption methods. Shortening of fluorescence lifetime of the C60 moiety in PVCz-C60 was observed, suggesting that the charge-separation takes place via the excited singlet state of C60; the rate constants of the charge-separation were evaluated to be larger than 10(9) S(-1) in polar solvents. In the nanosecond transient absorption spectra in the visible and near-IR regions obtained by excitation of the C60 moiety, the generation of PVCz(*+)-C60(*-) was confirmed. The time profiles of these radical ions showed slow decay continuing more than 800 micros in polar solvents. From the simulations of the decay curves on the basis of the proposed kinetic model, in which the charge-recombination takes place competitively with hole-migration, the rate parameters have been evaluated; i.e., the rate constant of hole migration was evaluated to be 5 x 10(7) s(-1), which was 50 times faster than that of the charge-recombination (ca. 10(6) s(-1)) in polar solvent. The charge-recombination takes place after hole migration among 200-300 Cz units along the PVCz chain in PVCz-C60.     

A new family of NAD(P)H-dependent oxidoreductases distinct from conventional Rossmann-fold proteins

A new family of NAD(P)H-dependent oxidoreductases is now recognized as a protein family distinct from conventional Rossmann-fold proteins. Numerous putative proteins belonging to the family have been annotated as malate dehydrogenase (MDH) or lactate dehydrogenase (LDH) according to the previous classification as type-2 malate/L-lactate dehydrogenases. However, recent biochemical and genetic studies have revealed that the protein family consists of a wide variety of enzymes with unique catalytic activities other than MDH or LDH activity. Based on their sequence homologies and plausible functions, the family proteins can be grouped into eight clades. This classification would be useful for reliable functional annotation of the new family of NAD(P)H-dependent oxidoreductases.     

Biodegradation of phenolic environmental pollutants by a surfactant-laccase complex in organic media

Oxidative degradation of phenolic environmental pollutants in organic media was investigated using a laccase complexed with surfactants. The catalytic activity of the surfactant-laccase complex in isooctane was markedly enhanced by appropriately adjusting the water content of the reaction medium using reverse micelles. The surfactant-laccase complex showed little activity towards the oxidative reaction of bisphenol A in water-saturated isooctane (i.e., 0.0055% [v/v] water) while effectively catalyzed the same reaction in isooctane containing 4% (v/v) water, which is over the maximum water solubility. The latter system was homogeneous and was only achieved by the aid of reverse micelles. With respect to the oxidation of bisphenol A, two products, 4-isopropylphenol and 4-isopropenylphenol, were identified by gas chromatography-mass spectrometry (GC-MS) analyses, indicating the oxidative degradation of the bis-phenolic structure of bisphenol A. We also found that the surfactant-laccase complex turned out to handle other environmental pollutants, chlorophenols, by the simultaneous addition of water and a redox mediator into the reaction medium using reverse micelles.     

Generation of harmonic distortion at fibre connectors

Harmonic distortion generated by the Fabry-Perot resonator at fibre connectors is described. The maximum second-harmonic distortion is calculated as a function of end separation for GaAlAs lasers. A ?42 dB second-harmonic distortion is generated in 100 ?m end separation, which is harmful in analogue transmission systems.     

New sensitivity measures for resistively terminated LC filters

Two new sensitivity measures for resistively terminated LC filters with arbitrary network structures are proposed. One gives an upper bound of the absolute sum of the second-order sensitivities of the operating propagation attentuation function with respect to the reactive elements. This measure, however, is based on the supposition of the invariance of the attenuation poles. the other gives an upper bound of the absolute sum of the first-order sensitivities of the group delay characteristic with respect to the reactive elements. Both the measures can be evaluated only from the prescribed characteristic function of the network. Some examples are included which show the utility of these measures for designing filters with favourable statistical tolerance in the passband.