Cloning of a gene for D-sorbitol dehydrogenase from Gluconobacter oxydans G624 and expression of the gene in Pseudomonas putida IFO3738

We have cloned a novel gene for d-sorbitol dehydrogenase (SLDH), which efficiently converted D-sorbitol to L-sorbose, from Gluconobacter oxydans G624 (FERM BP-4415). A cosmid library of the genomic DNA was screened by assaying SLDH activity. The inserted DNA from a positive clone was downsized by subcloning into charomid and pUCP plasmid, successively. Sequencing analysis of the DNA responsible for SLDH activity revealed an open reading frame of 1455 bp coding for 485 amino acid residues with a calculated molecular mass of 53,642 Da. The amino acid sequence showed 42.2% identity with a NAD+-dependent mannitol dehydrogenase (MDH), which catalyzed conversion of d-sorbitol to d-fructose, from Pseudomonas fluorescens DSM50106. Since the intact SLDH was found to be very unstable during isolation and purification, this SLDH fused to 6 x His-tag was expressed in Pseudomonas putida IFO3738 and purified by immobilized metal affinity chromatography using cobalt-based resins. The 6 x His-tag SLDH catalyzed the oxidation of D-sorbitol to L-sorbose and exhibited 15 times higher activity in the presence of NADP+ than that of NAD+. These results indicate that the SLDH is a novel kind of dehydrogenase distinct from MDH previously reported.     

Role of Stripes in Spin and Charge Dynamics of Underdoped La2−x Sr x CuO4

We investigate the electronic states of underdoped La _2–x Sr _x CuO ₄ (LSCO) by using a microscopic model, i.e., t-t-t-J model, containing charge stripes. The numerically exact diagonalization calculation is employed on small clusters. The physical properties observed in the angle-resolved photoemission and optical conductivity experiments are consistently explained in the model with vertical stripes, but not diagonal ones. These results demonstrate a crucial role of the vertical stripes in underdoped LSCO.     

Clinical usefulness of serum PIVKA-II levels determined by ECLIA system as a tumor maker for hepatocellular carcinoma

PIVKA-II is well known as a tumor maker of hepatocellular carcinoma (HCC). We measured serum PIVKA-II concentrations with a commercially available PIVKA-II immunoassay kit (Picolumi PIVKA-II: Eisai Co., Ltd., Tokyo) using Electrochemiluminescence Immunoassay (ECLIA). ECLIA system is a novel immunoassay system using a Ruthenium (II) Tris (bipyridyl) luminesced by electric energy. Cut off value was 40 mAU/ml by receiver-operating characteristic curves as a tumor maker for HCC. Eighty-nine out of 142 (62.2%) patients with HCC had elevated serum PIVKA-II levels and seventeen out of 36 (47.2%) patients whose tumor size was below 2 cm in diameter showed high PIVKA-II levels. We determined the serial changes in serum PIVKA-II levels of two patients with HCC following initial therapy. In these patients, elevations of serum PIVKA-II levels determined by ECLIA system preceded the HCC relapse detected by imaging diagnostic procedures. In summary, this assay system is suitable for detecting small increases in PIVKA-II concentrations. Determination of PIVKA-II by this assay system is found to be useful for the early detection of HCC.     

Wideband and high-power compressively strained GaInAsP/InPmultiple-quantum-well ridge waveguide lasers emitting at 1.3 μm

Compressively strained 1.3-μm GaInAsP/InP multiple-quantum-well (MQW) ridge waveguide lasers were fabricated. Through optimizing the total well thickness, large bandwidth over 11 GHz was achieved, together with high quantum efficiency of about 0.48 W/A and high power output of 60 mW before rollover. The laser also showed less temperature sensitivity up to an elevated temperature of 85°C     

Two cases of cerebral aneurysm detected after recanalization of the middle cerebral artery]

Two cases of aneurysm incidentally detected after recanalization of middle cerebral artery (MCA) occlusion are reported. Patient 1 was a 62-year-old male with sudden onset of left hemiparesis. We performed emergent intravascular surgery. The initial cerebral angiography revealed occlusion at the M1 portion of the right MCA. After partial recanalization with a microcatheter, carotid angiography revealed a right M1-M2 junction aneurysm. Due to the risk of aneurysmal rupture, the thrombolytic procedure was stopped. Follow up angiography after 1 month revealed complete recanalization of the right MCA and a persistent aneurysm. Patient 2 was a 65-year-old male with left hemiparesis. The initial cerebral angiography revealed occlusion at the M1 portion of the right MCA. After 1 month follow-up cerebral angiography revealed spontaneous recanalization of the right MCA and an incidental aneurysm at the M1-M2 junction. Neck clipping of the aneurysm was performed. When using a microcatheter or microballoon catheter to treat arterial occlusion, surgeons should consider the possibility of a rupture of a hidden aneurysm.     

Wideband optical transmission in smectic liquid crystal lightmodulator at room temperature

Video rate optical transmission at room temperature (RT) for smectic liquid crystal light modulators (SLCLMs) and filter circuits has been demonstrated. The bandwidth of this system has been determined to be 5.6 MHz. Optical transmission of the National Television System Committee (NTSC) video signal at RT has been realised     

Structure and expression of the human SM22alpha gene, assignment of the gene to chromosome 11, and repression of the promoter activity by cytosine DNA methylation

The pore-forming alpha 1 subunit of L-type calcium (Ca2+) channels is the molecular target of Ca2+ channel blockers such as phenylalkylamines (PAAs). Association and dissociation rates of (-)devapamil were compared for a highly PAA-sensitive L-type Ca2+ channel chimera (Lh) and various class A Ca2+ channel mutants. These mutants carry the high-affinity determinants of the PAA receptor site in a class A sequence environment. Apparent drug association and dissociation rate constants were significantly affected by the sequence environment (class A or L-type) of the PAA receptor site. Single point mutations affecting the high-affinity determinants in segments IVS6 of the PAA receptor site, introduced into a class A environment, reduced the apparent drug association rates. Mutation I1811M in transmembrane segment IVS6 (mutant AL25/-I) had the highest impact and decreased the apparent association rate for (-)devapamil by approximately 30-fold, suggesting that this pore-lining isoleucine in transmembrane segment IVS6 plays a key role in the formation of the PAA receptor site. In contrast, apparent drug dissociation rates of Ca2+ channels in the resting state were almost unaffected by point mutations of the PAA receptor site.     

Theoretical concentration of solar radiation by central receiver systems

Solar concentrations by central receiver systems have been calculated theoretically for various values of obliquity of the incident radiation, assuming that plane heliostat-mirrors, sufficiently small in dimension, cover a circular field without clearance. Through this calculation, the performance characteristics of this system such as the availability of the radiant energy incident on the heliostat-field, the distribution of interruption by an adjacent mirror, the optimum rim-angle for the mean area- and the mean volume-concentration and the attainable temperature were revealed. The study was extended towards the practical problem of decreasing the number of heliostats by increasing the dimensions of heliostat-mirrors, and the effect of increasing mirror-dimensions was argued for both plane and curved mirrors.     

Metabolic disturbance of tryptophan-nicotinamide conversion pathway by putative endocrine disruptors, bisphenol A and styrene monomer

Bisphenol A, a monomer of polycarbonate plastics, disturbed the conversion pathway of the amino acid tryptophan to the vitamin nicotinamide. The conversion ratio of tryptophan to nicotinamide was reduced to 1/15 by feeding a diet containing 1% bisphenol A. A putative disturbing reaction is kynurenine-->3-hydroxykynurenine, which is catalyzed by kynurenine monohydroxylase. This is an FAD-enzyme and requires NADPH as a coenzyme. Styrene monomer (1% addition to a normal diet) did not affect the food intake or the body weight, but slightly reduced the conversion ratio of tryptophan-nicotinamide.