Double switch operation in cardiac anomalies with atrioventricular and ventriculoarterial discordance

Since June 1987, 10 of 19 consecutive patients with atrioventricular and ventriculoarterial discordance (average age 4 +/- 2 years) had undergone a double switch operation with the morphologically left ventricle used as a systemic ventricle. There were two combinations of procedures. Atrial switch combined with arterial switch was used in two patients who had a normal pulmonary valve. Atrial switch combined with ventriculoarterial switch by Rastelli's procedure was used in eight patients with pulmonary stenosis or atresia and a large ventricular septal defect. One early death and two late deaths have occurred in a postoperative follow-up period of up to 4 years. Subsequent problems were mainly related to the results of atrial switch procedures in patients who had a small atrium because of low pulmonary flow, especially in patients with apicocaval juxtaposition. Our experience suggested that the double switch operation would open a new era of definitive surgical treatment in half of the patients with atrioventricular and ventriculoarterial discordance.     

DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) IN SEDIMENTS AND BENTHOS COLLECTED ON THE COAST OF CHIBA

Eight polycyclic aromatic hydrocarbons (PAHs) including benzo[a]pyrene were analyzed in sediment and benthos collected on the coast of Chiba Prefecture in Japan by gas chromatography-mass spectrometry (GC/MS). The total concentration of the PAHs ranged from 8 to 18 μ g/kg-dry in the sediments and from 36 to 59 μ g/kg-wet in the benthos, Mactra quadrangularis, Scoletoma nipponica, and Arenicola basiliensis. The PAH composition in the sediments and the benthos was similar at four sampling points and dominated by phenanthrene (Phe), fluoranthene (Flu), and pyrene (Pyr). The ratios of abundance of Flu to that of Pyr, Flu/Pyr, and of Phe/anthracene suggest that the PAHs in the benthos are derived from the combustion of fossil fuels. The ratio, R, of the PAH concentration in the benthos to that in the sediment is 2.0 for Scoletoma nipponica and 1.8 for Arenicola basiliensis in average, indicating that the bioaccumulation is not significant in the benthos. However, the R value for perylene in Scoletoma nipponica was 3.7 times as large as the average.     

THE FATE AND BEHAVIOR OF POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) THROUGH FEEDING AND EXCRETION OF ANNELIDS

The concentration of polycyclic aromatic hydrocarbons (PAHs) in sediment and excrements of annelids was measured by gas chromatography-mass spectrometry (GC/MS) and the movement of PAHs in the tidal flat was investigated. The PAH concentrations ranged 4.4–80.4 and 61.2–286.9 μg/kg-dry for the excrement of Arenicola basiliensis and of Marphysa sanguinea, respectively; the former contained about 10 times as much PAHs as the sediment and the latter about 100 times. The difference in the PAH concentration between the two organisms was attributed to their feeding behavior; M. sanguinea intakes much more detritus containing PAHs than A. basiliensis. Moreover, after the excrement of M. sanguinea had stood on the sediment for 2 hours, the PAH concentrations decreased to half. The reduction of the PAHs may arise from chemical changes owing to microorganisms and/or enzymes in the excrement of M. sanguinea.     

Direct dark matter search program with bolometers at the University of Tokyo

Bolometers are being developed at the University of Tokyo aiming at a search for galactic dark matter. We have succeeded in constructing a small-sized bolometer with 2.8 gram of lithium fluoride crystal with an rms energy resolution of 3.8 ke V for 60-ke V rays. Both lithium and fluorine are expected to be suitable for the detection of possible particle dark matter with a spin-dependent interaction like supersymmetric neutralinos. Fabrication of Neutron Transmutation Doped (NTD) germanium is also in progress to make a number of thermistors with uniform sensitivities to be used for multi-module bolometers. When the development of a full-sized detector with a total mass of order one kilogram is completed, we plan to install it in the Kamioka underground laboratory.     

Construction of block-shuffled libraries of DNA for evolutionary protein engineering: Y-ligation-based block shuffling

Evolutionary protein engineering is now proceeding to a newstage in which novel technologies, besides the conventionalpoint mutations, to generate a library of proteins, are required.In this context, a novel method for shuffling and rearrangingDNA blocks (leading to protein libraries) is reported. A cycleof processes for producing combinatorial diversity was devisedand designated Y-ligation-based block shuffling (YLBS). Methodologicalrefinement was made by applying it to the shuffling of module-sizedand amino acid-sized blocks. Running three cycles of YLBS withmodule-sized GFP blocks resulted in a high diversity of an eight-blockshuffled library. Partial shuffling of the central four blocksof GFP was performed to obtain in-effect shuffled protein, resultingin an intact arrangement. Shuffling of amino acid monomer-sizedblocks by YLBS was also performed and a diversity of more than10¹⁰ shuffled molecules was attained. The deletion problemsencountered during these experiments were shown to be solvedby additional measures which tame type IIS restriction enzymes.The frequency of appearance of each block was skewed but waswithin a permissible range. Therefore, YLBS is the first generalmethod for generating a huge diversity of shuffled proteins,recombining domains, exons and modules with ease.     

Position detection method for microwell chip on microscope stage by photon multiplier tube

In this paper, we propose a position detection method for a microwell with manageable volume (MMV) chip on the stage of the inverted microscope. When the manipulation robot arm puts an MMV chip on the microscope stage, there is alignment error up to 500 μm. This error affects measurement accuracy of fluorescence from solution filled in a tiny hall of the MMV chip. Usually, CCD image processing is used for detecting a position. However, appending a CCD camera to our microscope increases the complexity of the optical system. Therefore, we used a photon multiplier tube which was already equipped for measuring fluorescence. In the result, the position of the MMV chips was detected by putting a pilot LED directly above the objective lens. The detection error was less than 10 μm. Although this method was devised for our system, we considered that it was available in other micro optics systems.     

Impartation of hydroxyapatite formation ability to ultra‐high molecular weight polyethylene by deposition of apatite nuclei

The authors aimed to impart hydroxyapatite formation ability to ultra‐high molecular weight polyethylene (UHMWPE) by deposition of apatite nuclei (ApN) by the following two methods. The first method was electrophoretic deposition (EPD). A porous UHMWPE was placed between electrodes in the ApN‐dispersed ethanol and constant voltage was applied. By this treatment, the ApN were migrated from anode‐side surface to the cathode one through the pores by an electric field in the pores of the UHMWPE and deposited inside the pores. The second method was direct precipitation (DP) of the ApN. A porous UHMWPE was soaked in a simulated body fluid (1.0SBF) with higher pH than the physiological one and subsequently, its temperature was raised. By this treatment, the ApN were precipitated in the pores of the UHMWPE directly in the reaction solution. For both methods, the ApN‐deposited UHMWPE showed HAp formation ability not only on the top surface but also inside the pores near the surface of the porous UHMWPE in 1.0SBF although the adhesion strength of thus‐formed HAp layer was higher in the case of the EPD in comparison with the DP, oxygen plasma treatment before the DP enabled to achieve a similar level of the HAp layer adhesion to the EPD.Inspec keywords: calcium compounds, adhesives, porous materials, precipitation, plasma materials processing, pH, adhesion, polymers, phosphorus compounds, electrophoretic coatings, electrochemical electrodesOther keywords: hydroxyapatite formation ability, ultrahigh molecular weight polyethylene, apatite nuclei, electrophoretic deposition, EPD, porous UHMWPE, ApN‐dispersed ethanol, ApN‐deposited UHMWPE, HAp formation ability, oxygen plasma treatment, anodes, cathodes, electric field, direct precipitation, pH value, reaction solution, adhesion strength, HAp layer adhesion, Ca₁₀ (PO₄)₆ (OH)₂      

ETHANOL FERMENTATION WITH SHOCHU DISTILLERY WASTE AND AROMATIC RED RICE BRAN

Shochu distillery waste which had been exhausted by a vacuum-distillation procedure at low temperature (35–40°C) was used for secondary ethanol fermentation with the bran of aromatic red rice (Oryza sativa var. Indica, Tapol). The filtrate of the fermented mash made from kome shochu distillery waste and aromatic red rice bran had a characteristic wine-like red color, contained about 12% ethanol (v/v), and possessed a fine aroma that was fortified with the aromas of higher alcohols and volatile esters during secondary ethanol fermentation. A novel red alcoholic beverage was produced from the industrial by-product of shochu-making, kome shochu distillery waste and a by-product of Sekihan-cooking, aromatic red rice bran. The filtrate of the fermented mash had a characteristic absorbance at 530 nm. As the amounts of aromatic red rice bran in the mash were increased, the absorbance at 530 nm increased. Thus, a novel system utilizing shochu distillery waste, which is conventionally treated as wastewater, and aromatic red rice bran was established economically using a simple vacuum-distillation and secondary ethanol-fermentation procedure without the need for any complicated or expensive processes.