<Preliminary>An Enzymatic Study of an Oxalate Producing System in Relation to the Glyoxylate Cycle in White-rot Fungus Phanerochaete chrysosporium

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Designing Novel Breeding Strategies for Producing High-Oil Crops Based on a Molecular Understanding of Triacylglycerol Metabolism

Seeds are storage organ in plants and main resource of plant oils to human civilization and the demand of plant oils are increasing yearly and expansion of the production capacity is an urgent issue worldwide. Thus, it is necessary to improve oil yields per unit area and generation of crops with high-oil content is needed. Arabidopsis thaliana plays a vital role in advancement of genetics and molecular biology in plant sciences. The forward and reverse genetic approaches with Arabidopsis have provided an overview of triacylglycerol metabolism. The elucidation of the overview contributes to understanding of spatiotemporal regulation of a metabolic flow of triacylglycerol metabolism in plant cell. This understanding sheds light on bottlenecks in triacylglycerol biosynthesis and provides novel clues for increasing seed triacylglycerol content. Recent advance in metabolic engineering approaches demonstrate several evidences that triacylglycerol metabolism is coordinated with other metabolisms. Most notably, triacylglycerol biosynthesis competes with biosynthesis of starch or seed storage proteins. These studies indicate that alterations of the metabolic pathways to avoid the competitions could be a novel concept for increasing seed oil content

Involvement of butyrate in electrogenic K+ secretion in rat rectal colon

Short-chain fatty acids (SCFAs), such as acetate, propionate, and butyrate, are synthesized from dietary carbohydrates by colonic bacterial fermentation. These SCFAs supply energy, suppress cancer, and affect ion transport. However, their roles in ion transport and regulation in the intracellular environment remain unknown. In order to elucidate the roles of SCFAs, we measured short-circuit currents (ISC) and performed RT-PCR and immunohistochemical analyses of ion transporters in rat rectal colon. The application of 30 mM butyrate shifted ISC in a negative direction, but did not attenuate the activity of epithelial Na+ channels (ENaC). The application of bumetanide, a Na+-K+-2Cl− cotransporter inhibitor, to the basolateral side reduced the negative ISC shift induced by butyrate. The application of XE991, a KCNQ-type K+ channel inhibitor, to the apical side decreased the ISC shift induced by butyrate in a dose-dependent manner. The ISC shift was independent of HCO3− and insensitive to ibuprofen, an SMCT1 inhibitor. The mucosa from rat rectal colon expressed mRNAs of H+-coupled monocarboxylate transporters (MCT1, MCT4, and MCT5, also referred to as SLC16A1, SLC16A3, and SLC16A4, respectively). RT-PCR and immunofluorescence analyses demonstrated that KCNQ2 and KCNQ4 localized to the apical membrane of surface cells in rat rectal colon. These results indicate that butyrate, which may be transported by H+-coupled monocarboxylate transporters, activates K+ secretion through KCNQ-type K+ channels on the apical membrane in rat rectal colon. KCNQ-type K+ channels may play a role in intestinal secretion and defense mechanisms in the gastrointestinal tract

K+ channels on resting duct cells from rat pancreas

The ductal system of the exocrine pancreas produces HCO3--rich fluid in response to secretin and other stimuli. HCO3- efflux across the luminal membrane is mediated by a Cl--HCO3- exchanger operating in parallel with the cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel. Basolateral K+ channels provide an exit pathway for K+ and play a vital role in maintaining the membrane potential, which is a crucial component of the driving force for anion secretion. Measurements of membrane potential with intracellular microelectrodes suggested that Ba2+-sensitive K+ conductance accounts for more than 60% of the total basolateral ionic conductance in resting ducts (1). To identify the Ba2+-sensitive K+ channels, we isolated ducts from normal rat pancreas by collagenase digestion. We first demonstrated that the ducts did not express a vascular endothelial marker PECAM-1 (platelet/endothelial cell adhesion molecule-1), but expressed cytokeratin 20, a marker of duct cells (2), using immunofluorescent staining. In addition, monoclonal anti-CFTR antibody was detected near the luminal membrane of these cells. In cell-attached single-channel recordings, we observed three types of K+ channels on basolateral membrane in unstimulated duct cells. The 40 pS K+ channels are likely to mediate whole-cell inwardly rectifying K+ (Kir) currents, which were blocked by extracellular Ba2+ in a voltage-dependent manner. The properties of 90 pS and 170 pS K+ channels are similar to those of Ca2+-activated K+ channels. We then identified Kir2.0 and SK4/IK1 (intermediate conductance Ca2+-activated K+ channel) subunits as molecular candidates of the K+ channels using RT-PCR analysis. The present results suggest that these subunits may mediate native K+ currents in resting duct cells. Further functional studies with specific blockers are required to evaluate which of these K+ channels contribute to the resting membrane potential and might be involved in HCO3- secretion

Translating, adapting, and validating the medical student version of the patient care ownership scale for use in Japan

BackgroundPatient care ownership (PCO) among medical students is a growing area in the field of medical education. While PCO has received increasing attention, there are no instruments to assess PCO in the context of Japanese undergraduate medical education. This study aimed to translate, culturally adapt, and validate the PCO Scale – Medical students (PCOS-S) in the Japanese context.MethodsWe collected survey data from fifth- and sixth-grade medical students from five different universities varying in location and type. Structural validity, convergent validity, and internal consistency reliability were examined.ResultsData from 122 respondents were analyzed. Factor analysis of the Japanese PCOS-S revealed three factors with Cronbach’s alpha values exceeding the satisfactory criterion (0.70). A positive correlation was observed between the total Japanese PCOS-S scores and the global rating scores for the clinical department as a learning environment (Pearson’s correlation coefficient = 0.61).ConclusionsWe conducted the translation of the PCOS-S into Japanese and assessed its psychometric properties. The Japanese version has good reliability and validity. This instrument has potential value in assessing the development of medical students’ PCO

Exact Solutions of Holonomic Quantum Computation

Holonomic quantum computation is analyzed from geometrical viewpoint. We develop an optimization scheme in which an arbitrary unitary gate is implemented with a small circle in a complex projective space. Exact solutions for the Hadamard, CNOT and 2-qubit discrete Fourier transform gates are explicitly constructed.Comment: 11 pages, re-organized to be more comprehensive, references added, style file of Physics Letters A is neede

Magneto-Plastic Effect in Nickel Single Crystals

It has been observed that the flow stress of a nickel single crystal can be lowered about 15% by applying an alternating magnetic field parallel to the specimen axis during plastic deformation at -194℃. This phenomenon, named by us as the magneto-plastic effect, can be interpreted qualitatively in terms of a concept that oscillating magnetic domain walls give a force on dislocations. In order to clarify this effect, its dependence on the temperature, plastic strain, strain rate, and on the strength and frequency of the alternating magnetic field applied have been measured. The activation volumes in relation to a thermally activated process of dislocation motion were also obtained from the stress relaxation curves measured after and before the application of an alternating magnetic field, and they were compared mutually at various values of the shear stress

Microscopic Characterization of the L10-FePt Nanoparticles Synthesized by the SiO2-Nanoreactor Method

We investigated magnetic properties of the L10-FePt nanoparticles synthesized by the SiO2-nanoreactor method by means of Moessbauer spectroscopy from the microscopic point of view. Almost all of the nanoparticles were revealed to have nearly the same Moessbauer hyperfine parameters as those of the bulk L10-FePt alloy, indicating that they have well-defined L10 structure equivalent to the bulk state in spite of their small size of 6.5 nm.Comment: 13 pages, 4 figure