Grapefruit juice enhance the uptake of coenzyme Q10 in the human intestinal cell-line Caco-2

Coenzyme Q10 (CoQ10) is very widely consumed by humans as a food supplement. However, CoQ10 is taken up from the intestine into the circulation at a low rate. The absorption of compounds from the gastrointestinal tract is one of the important determinants for oral bioavailability. Secretory transport limits the oral bioavailability of compounds. It has been reported that efflux transport of CoQ10 is mediated by P-glycoprotein (P-gp) in Caco-2 cells. We tried to improve intestinal absorption of CoQ10 by modulating P-gp. Since grapefruit juice (GFJ) is reported to inhibit P-gp function, we investigated the effect of GFJ on the transport of CoQ10 by Caco-2 cells. In the presence of GFJ, the basal-to-apical transport of CoQ10 was decreased and the uptake of CoQ10 was increased. These findings suggest that the combined administration of CoQ10 and GFJ could enhance CoQ10 absorption.     

Quantitative Estimation of Dark Muscle Content in the Mackerel Meat Paste and its Products Using Antisera Against Myosin Light Chains

ABSTRACT: Based on the high level of extractability of myosin subunits (light chains), even after prolonged heat treatment of muscle, a new method to evaluate the dark muscle content in the fish meat and products of mackerel is proposed. Tissue-specific rabbit antisera with myosin light chains (A1 from ordinary muscle and D1 from dark muscle) from mackerel Scomber japonicus were obtained. Mackerel meat paste (surimi) was dissolved in 8 M urea containing 1% SDS, and diffused on agar plates containing antiserum against A1 or D1 by single radial immunodiffusion (SRID). The results obtained showed that the area of halos formed in the plates was quite proportional to the content of dark muscle.     

DC characteristic simulation for floating gate neuron MOS circuits

An original approach to DC characteristic SPICE simulation for floating gate neuron MOS circuits is demonstrated. A novel macromodel which calculates the floating gate potential by combining resistances and dependent voltage and current sources is introduced. Utilising this method, DC characteristics for neuron MOS circuits have been confirmed to be successfully simulated using SPICE     

Stratospheric ozone and ClO measurement using Balloon-Borne submillimeter limb sounder

Stratospheric O/sub 3/ and ClO were simultaneously observed off the northeastern coast of Japan by the Balloon-Borne Superconducting Submillimeter-Wave Limb-Emission Sounder (BSMILES) developed at National Institute of Information and Communications Technology. BSMILES is a highly sensitive submillimeter radiometer that exploits the superconductor-insulator-superconductor (SIS) technology for atmospheric research. This paper presents the first BSMILES spectra, and describes the details of the calibration process. The vertical profiles of O/sub 3/ and ClO have been also retrieved. In spite of some calibration uncertainties the obtained profiles are in relatively good agreement with previous and other available measurements.     

Soluble High-Temperature Polymers Containing a Tetraphenylthiophene Unit

Soluble high-temperature polymers containing a tetraphenylthiophene unit were successfully prepared. Four types of tetraphenylthiophene monomers—diamine, diisocyanate, dicarboxylic acid chloride, and dibromide—were synthesized starting from tetraphenylthiophene, which was readily obtained by the reaction of benzyl chloride and sulfur. Aromatic polyimides and copolyimides were prepared by the reactions of tetraphenylthiophene diamine with tetracarboxylic dianhydrides, tetraphenylthiophene diisocyanate with tetracarboxylic dianhydrides, and tetraphenylthiophene diamine with tetracarboxylic dithioanhydrides. Aromatic polyamides and copolyamides were obtained from the reaction pairs of tetraphenylthiophene diamine and dicarboxylic acid chlorides, tetraphenylthiophene dicarboxylic acid chloride and diamines, and tetraphenylthiophene dibromide, diamines, and carbon monoxide. Similarly aromatic polyamide-imides were prepared by the reaction of tetraphenylthiophene diamine with 4-chloroformylphthalic anhydride, and tetraphenylthiophene diisocyanate with trimellitic anhydride. The reaction of tetraphenylthiophene dicarboxylic dichloride with bisphenols and aminophenols afforded aromatic polyesters and polyamide-esters, respectively. Aromatic polyazomethines were prepared by the reaction of tetraphenylthiophene diamine and dialdehydes. All the polymers were obtained in high molecular weights, and all were soluble in organic solvents and had high glass transition temperatures around 300°C.     

Development of a novel hydrate-based refrigeration system: A preliminary overview

This paper gives a preliminary overview of our attempt at developing a hydrate-based refrigeration system based on a novel conceptual design. The system forms a closed cycle, which is more or less analogous to the conventional vapor-compression refrigeration cycle. The cycle of present interest is performed by a multiphase refrigerant, which is typically a mixture of one or two hydrate-forming substances and water. The refrigerant is required to form a hydrate at a temperature as high as 30 °C or above, desirably under a modest pressure, such that the heat released by the exothermic hydrate formation can be efficiently removed by an environmental fluid such as the atmospheric air, groundwater or river water. The hydrate slurry thus formed is depressurized to dissociate at a lower temperature, typically 5–9 °C, thereby absorbing heat from a space to be refrigerated. To confirm the feasibility of the above conceptual design of the hydrate-based refrigeration system, a thermodynamic analysis of the system and a simulation of its operation have been performed. Also a laboratory-scale refrigerator based on the above design was constructed and tested. The paper summarizes the results of these efforts to show the potential advantages of the hydrate-based refrigeration system over conventional ones and to give the prospects of our refrigeration-system development.     

Sensorless control of SRM using magnetizing curves

Among various variable speed drives, switched reluctance motors (SRMs) have been found to be competitive with traditional ac and dc motors because of their simple construction and drive electronics. However, the necessity of using a shaft‐mounted position sensor is one of the drawbacks of the SRM from the standpoint of cost, size, and reliability. Position sensorless SRM drives are expected to solve these problems. This paper presents a method of position sensorless control based on a simple fuzzy model of nonlinear position‐dependent magnetizing curves. The sensors needed for the drive are one voltage sensor and one current sensor. Experimental studies using a 1.5‐kW, 5400‐rpm SRM with a 6/4 tooth configuration show that the maximum error of rotor position estimation is less than three mechanical degrees in the 1:20 speed range under any load conditions. © 2001 Scripta Technica, Electr Eng Jpn, 135(2): 60–68, 2001     

Photocatalytic inactivation and removal of algae with TiO<Subscript>2</Subscript>-coated materials

The capabilities of TiO₂-coated materials for the inactivation and removal of algae were investigated. As supports for TiO₂, non-woven fabric and Ni foam were chosen. To evaluate the ability of noble metal cocatalyst additions to facilitate the photocatalytic algal inhibition of TiO₂-coated materials, Pd nanoparticles were deposited on non-woven fabric-supported TiO₂ by photoelectrochemical deposition. The fabric-supported Pd/TiO₂ showed higher inhibition activity for algal growth compared to the fabric-supported TiO₂ without Pd. In addition, Ni foam-supported TiO₂ also showed high inhibition activity, both in laboratory-scale tests and open-air tests. Therefore, TiO₂-coated materials with suitable coating methods such as the use of cocatalysts or large surface area can substantially inhibit algal growth. The ability of the TiO₂-coated materials to inhibit algae correlated well with their activity for the photocatalytic decolorization of methylene blue, suggesting a nonspecific mechanism in the breakdown of cellular structures.     

Thermally-stimulated current and dielectric loss measurement ofpolypropylene and Teflon-FEP films immersed in diarylethane

Some properties of oil/PP (biaxially stretched polypropylene) and oil/FEP (Teflon FEP) composite insulators have been investigated with TSC (thermally stimulated current) techniques. The oil/PP system showed three TSC peaks originating from carriers captured in the swollen surface region of the PP. The TSC spectra depended strongly on the polarity of the poling voltage and on the impregnating temperature. Their analysis yielded information on the carrier traps existing near the PP surface in the oil/PP interface region. On the other hand, the TSC spectrum of the oil/FEP system has a small impregnating temperature dependence and a small effect of the poling voltage polarity. The difference in TSC between oil/PP and oil/FEP systems is closely related to the difference in the oil-polymer interaction. The TSC is a useful method for investigating carrier traps in the surface region and their change due to the oil-polymer interaction. To investigate further the relation between the carrier traps and tanδ, collecting bias TSC was measured on a specimen to which an ac voltage was applied. The results indicate that the decrease in tanδ during the ac voltage application depends on the amount of trapped carriers near the polymer's surface or, the decrease in carriers in the oil     

Chemical Modification of Novel Alkyne-Containing Polymers Obtained by Radical Polymerization of Conjugated Enynes

Summary Alkyne-containing polymers, obtained by the radical polymerization of 4-substituted conjugated enynes (CH₂=CH—CC—R: R—= Ph— and n-Bu—), were subjected to polymer reactions through their alkyne moieties. That is, the radical addition of a thiol fragment, the hydrosilylation, and reduction via the hydroalumination were carried out to give polymers bearing alkenyl sulfide, alkenylsilane, and alkene moieties, respectively.