Heme content of recombinant catalase from Psychrobacter sp. T-3 altered by host Escherichia coli cell growth conditions.

The catalase gene of Psychrobacter sp. T-3 was cloned, and the gene product (PktA) was overexpressed in Escherichia coli. The specific activity of the purified PktA was slightly lower than that of the native purified enzyme obtained from Psychrobacter sp.

Effects of ultraviolet-B irradiation on the cuticular wax of cucumber (Cucumis sativus) cotyledons.

Cucumber seedlings were grown under three doses of supplemental ultraviolet-B (UV-B) irradiation to examine the effects on the surface structure of the cotyledons. Medium and high doses of irradiation induced glazing (formation of translucent, glossy layers) on the adaxial surfaces of cotyledons, especially those exposed to a high dose of UV-B. Observation with a scanning electron microscope revealed that the adaxial surfaces of cotyledons exposed to a medium dose of UV-B and controls became rough in appearance, but unevenness of the surface was not apparent in cotyledons irradiated with a high dose of UV-B.

Kinetic studies on lipase-catalyzed acetylation of 2-alkanol with vinyl acetate in organic solvent.

Lipase-catalyzed acetylation of 2-alkanol with vinyl acetate has been studied kinetically using Burkholderia cepacia lipase (BCL), enantiomerically pure (R)- and (S)-2-alkanols and different organic solvents. The rate equation was derived by the steady state method for the simplified mechanism. The second order rate constants (k(R) and k(S)) for (R)- and (S)-2-alkanols were evaluated from the slopes of the double reciprocal plots, v(-1) vs.

Development of a miniature motor-driven pulsatile LVAD driven by a fuzzy controller.

We have been developing a small, lightweight motor-driven pulsatile left ventricular assist device (LVAD) with a ball screw. The motor-driven LVAD consists of a brushless DC motor and a ball screw. The attractive magnetic force between Nd-Fe-B magnets (with a diameter of 5 mm and a thickness of 1.

Analysis of heat generation of lithium ion rechargeable batteries used in implantable battery systems for driving undulation pump ventricular assist device.

We have developed internal battery systems for driving an undulation pump ventricular assist device using two kinds of lithium ion rechargeable batteries. The lithium ion rechargeable batteries have high energy density, long life, and no memory effect; however, rise in temperature of the lithium ion rechargeable battery is a critical issue. Evaluation of temperature rise by means of numerical estimation is required to develop an internal battery system.

Induction and inhibition of cyclobutane pyrimidine dimer photolyase in etiolated cucumber (Cucumis sativus) cotyledons after ultraviolet irradiation depends on wavelength.

Under polychromatic ultraviolet (UV) irradiation (maximum energy at 327 nm) the activity of DNA photolyase specific to cyclobutane pyrimidine dimers (CPDs), CPD photolyase, increased by an amount which depended on UV irradiance, and the level of CPD photolyase gene (CsPHR) transcripts temporarily increased before the activity reached a constant level. UV light (>320 nm) was more effective than visible light at increasing CPD photolyase activity. In contrast, monochromatic UV irradiation at wavelengths <300 nm increased the level of CsPHR transcripts similarly to irradiation at wavelengths >320 nm, but reduced CPD photolyase activity compared with the dark control.

Glaciecola chathamensis sp. nov., a novel marine polysaccharide-producing bacterium.

Two novel exopolysaccharide-producing bacteria, strains S18K6(T) and S18K5, were isolated from Pacific Ocean sediment. The isolates were Gram-negative, motile, strictly aerobic chemoheterotrophic bacteria. The DNA G+C contents of strains S18K6(T) and S18K5 were 44.

Antioxidative activity and ameliorative effects of memory impairment of sulfur-containing compounds in Allium species.

The antioxidative activity and ameliorative effects on memory impairment by sulfur-containing compounds which occur in Allium vegetables such as onion and garlic were investigated. The antioxidative activities of S-alk(en)yl-L-cysteines and their sulfoxides, volatile alk(en)yl disulfides and trisulfides, and vinyldithiins were examined by using human low-density lipoprotein. It was elucidated that the alk(en)yl substituents and the number of sulfur atoms in the compounds were important for the antioxidative activities.

Numerical estimation of heat distribution from the implantable battery system of an undulation pump LVAD.

We have been developing an implantable battery system using three series-connected lithium ion batteries having an energy capacity of 1,800 mAh to drive an undulation pump left ventricular assist device. However, the lithium ion battery undergoes an exothermic reaction during the discharge phase, and the temperature rise of the lithium ion battery is a critical issue for implantation usage. Heat generation in the lithium ion battery depends on the intensity of the discharge current, and we obtained a relationship between the heat flow from the lithium ion battery q(c)(I) and the intensity of the discharge current I as q(c)(I) = 0.

Development of integrated electronics unit for drive and control of undulation pump-left ventricular assist device.

In this study, we have developed an implantable electronics unit (IEU) for driving an undulation pump-left ventricular assist device (UP-LVAD). The IEU consists of a pump driver, three series-connected lithium ion batteries (1800 mAh), a charger, and a transcutaneous information transmission system. These electronic subunits were encapsulated in a case (110 x approximately 80 x approximately 30 mm) made of epoxy resin.

Estimation of early-stage malfunction using implantable artificial heart sound in animal experiments.

We have developed an automatic diagnosis system of an artificial heart in order to ensure the safety of the patient implanted with the artificial heart. The automatic diagnosis system is composed of an electro-stethoscope system, adaptive noise canceller (ANC), and artificial neural network (ANN). The ANC effectively eliminates ambient noise from the sound signal of the artificial heart detected by the electro-stethoscope, and a filtered sound signal is separated into each frequency components by fast Fourier transformation.

Oxidative DNA damage in cucumber cotyledons irradiated with ultraviolet light.

DNA was isolated from the cotyledons of cucumber seedlings irradiated with ultraviolet (UV)-C (254 nm) or UV-B+UV-A (280-360 nm; maximum energy at 312 nm) at various fluence rates and durations. Following enzymatic hydrolysis of DNA, the content of 8-hydroxy-2'-deoxyguanosine [(8-OHdG), 8-oxo-7,8-dihydro-2'-deoxyguanosine], a well-established biomarker closely identified with carcinogenesis and aging in animal cells, was determined using a high-performance liquid chromatograph equipped with an electrochemical detector. The levels of 8-OHdG increased with UV-C and UV-B irradiation in a fluence-dependent manner.

Development of a bidirectional transcutaneous optical data transmission system for artificial hearts allowing long-distance data communication with low electric power consumption.

We have developed a wavelength division bidirectional transcutaneous optical data transmission system using amplitude shift keying (ASK) modulation. The bidirectional optical data transmission system consists of two kinds of light emitting diodes (LEDs) having different wavelengths and an ASK modulator and demodulator. Two narrow directional visible LEDs with a peak output wavelength of 590 nm were used to transmit data from inside the body to outside the body, and a narrow directional near-infrared LED with a peak output wavelength of 940 nm was used for transmission from outside the body to inside the body.

Production of two types of exopolysaccharide by Novosphingobium rosa.

A bacterium, Ikeda-3, that was isolated from the wastewater of a winery was found to produce floating and precipitating exopolysaccharides (EPSs) when grown aerobically in a medium containing sucrose as the sole carbon source. The concentrations of floating and precipitating EPSs were approximately 2.7 g/l and 0.

Production of a novel exopolysaccharide by Rahnella aquatilis.

A bacterium Tomakomai B-1 that was isolated from the activated sludge of a treatment process for wastewater of the pulp industry was found to produce soluble and insoluble exopolysaccharides (EPSs) when grown aerobically in a medium containing sucrose as the sole carbon source. The sugar component of soluble EPSs consisted of rhamnose, mannose, galactose, glucose, mannuronic acid, galacturonic acid and glucuronic acid, and that of insoluble EPSs consisted of rhamnose, mannose, galactose, glucose, mannuronic acid and glucuronic acid. The concentrations of insoluble and soluble EPS were approximately 1.

Antioxidative activity of sulfur-containing compounds in Allium species for human LDL oxidation in vitro.

Sulfur-containing compounds contributing to health promotion in Allium species are produced via enzymic and thermochemical reactions. Sulfur-containing amino acids and volatile organosulfur compounds were prepared for an antioxidative assay. The inhibitory activity of S-alk(en)yl-L-cysteines and their sulfoxides, volatile alk(en)yl disulfides and trisulfides, and vinyldithiins in Allium species against lipid hydroperoxide (LOOH) formation in human low-density lipoprotein (LDL) was examined.

Exiguobacterium oxidotolerans sp. nov., a novel alkaliphile exhibiting high catalase activity.

A novel alkaliphile was isolated from a drain of a fish processing plant. The isolate grew at a pH range of 7-10. Cells were Gram-positive, facultatively aerobic, motile rods with peritrichous flagella.

Bacillus asahii sp. nov., a novel bacterium isolated from soil with the ability to deodorize the bad smell generated from short-chain fatty acids.

In a screening campaign to isolate strains with the ability to remove the bad smell associated with animal faeces, strain MA001(T) was isolated from a soil sample obtained from Shizuoka prefecture, Japan. The isolate grew at pH 6-9 but not at pH 10. Cells were Gram-positive, straight rods with peritrichous flagella and produced ellipsoidal spores.

Anoxybacillus voinovskiensis sp. nov., a moderately thermophilic bacterium from a hot spring in Kamchatka.

A novel moderately thermophilic bacterium, strain TH13T, was isolated from a hot spring in Kamchatka. It was found to be a Gram-positive, facultative aerobe; the straight, non-motile rods grew at 30-64 degrees C (optimum 54 degrees C). The isolate was positive for catalase and oxidase tests and reduced nitrate to nitrite, but was negative for H2S production and growth in more than 3% NaCl (w/v).

Development of an electro-stethoscope system and design of an optimum filter based on tissue sound transmission for noninvasive early diagnosis of malfunction of an implanted mechanical total artificial heart.

Early diagnosis of the malfunction of a mechanical artificial heart implanted in a patient who has been discharged from hospital is very important. We have developed an electro-stethoscope system that enables the malfunction of an artificial heart to be detected from the analysis of sound signals from the artificial heart. The sound data can be transmitted to a hospital via a mobile telephone or the Internet, so that doctors can examine the condition of the artificial heart.

Antioxidative activity of sulfur-containing compounds in Allium species for human low-density lipoprotein (LDL) oxidation in vitro.

Sulfur-containing compounds contributing to health promotion in Allium species are produced via enzymic and thermochemical reactions. Sulfur-containing amino acids and volatile organosulfur compounds were prepared for an antioxidative assay. The inhibitory activity of S-alk(en)yl-l-cysteines and their sulfoxides, volatile alk(en)yl disulfides and trisulfides, and vinyldithiins in Allium species against lipid hydroperoxide (LOOH) formation in human low-density lipoprotein (LDL) was examined.

Design of a miniature implantable left ventricular assist device using CAD/CAM technology.

In this study, we developed a new miniature motor-driven pulsatile left ventricular assist device (LVAD) for implantation into a Japanese patient of average build by means of computer-aided design and manufacturing (CAD/CAM) technology. A specially designed miniature ball-screw and a high-performance brushless DC motor were used in an artificial heart actuator to allow miniaturization. A blood pump chamber (stroke volume 55 ml) and an inflow and outflow port were designed by computational fluid dynamics (CFD) analysis.

Bacillus krulwichiae sp. nov., a halotolerant obligate alkaliphile that utilizes benzoate and m-hydroxybenzoate.

Obligate alkaliphilic strains, AM31D(T) and AM11D, that utilize benzoate and m-hydroxybenzoate were isolated from soil obtained from Tsukuba, Ibaraki, Japan. The isolates grew at pH 8-10, but not at neutral pH. They were Gram-positive, facultatively anaerobic, straight rods with peritrichous flagella and produced ellipsoidal spores.

Rhodococcus tukisamuensis sp. nov., isolated from soil.

A novel strictly aerobic, heterotrophic, mesophilic bacterium, strain Mb8(T), was isolated from soil in Sapporo City, Hokkaido, Japan. The G+C content of strain Mb8(T) was 66.0 mol%.

Ethylene evolution from tobacco leaves irradiated with UV-B.

Seedlings of Nicotiana tabacum L. (cv. Petit Havana SR1) were grown in the presence or absence of ultraviolet-B (UV-B, 290-320 nm) irradiation.