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BACKGROUND Interleukin-6 (IL-6) is a pleiotropic cytokine that confers androgen-independence and aggressiveness in prostate cancer (PCa); however, the molecular mechanisms regulating IL-6 expression remain unclear. The expression of ARID5A, an AT-rich interaction domain (ARID) DNA-binding motif-containing transcription factor is positively correlated with IL-6 expression in human PCa. We, therefore, hypothesized that ARID5A could regulate IL-6 expression in PCa. METHODS The relationship between ARID5A and IL-6 in PCa patients was analyzed using statistical analyses of multiple clinical microarray data sets. To investigate whether ARID5A regulates IL-6 expression, CRISPR-driven ARID5A knockout clones were established in DU145 and PC-3 cells. RESULTS Analysis of three microarray data sets showed a positive correlation between ARID5A and IL-6 expression. The expression of IL-6 in ARID5A knockout clones was significantly reduced compared with control clones in both PCa cell lines. Knockout of ARID5A did not result in any loss of IL-6 mRNA stability. Instead, we observed a significant decrease in the occupancy of both active RNA Polymerase II and the active histone mark, H3K4me3 at the IL-6 transcriptional start site in ARID5A knockout PCa cells, suggesting a role for transcriptional regulation. CONCLUSIONS Our study demonstrated that loss of ARID5A downregulates the expression of IL-6 at the transcriptional level.

Background The androgen receptor (AR) is one of the most important and dynamically regulated factors in prostate cancer (PCa) progression. Despite the importance of AR expression regulation, the precise mechanisms are not fully understood. ARID5B, an AT-rich interaction domain DNA-binding motif-containing transcription factor, is expressed higher in primary PCa than normal prostate, and correlated with AR expression. We therefore hypothesized that ARID5B could regulate AR expression. Methods Correlation between AR and ARID5B expression was analyzed using publicly and commercially available microarray data. To examine the role of ARID5B in AR expression, ARID5B was knocked down in VCaP and LNCaP cells, then mRNA and protein levels of AR were measured and an in vitro cell proliferation assay was performed. Chromatin immunoprecipitation was performed to further examine molecular mechanisms. Results Knockdown of ARID5B suppressed the AR mRNA and protein expression in VCaP and LNCaP cells and decreased in vitro cell proliferation. Suppression of ARID5B decreased the occupancy of active RNA polymerase II in the AR promoter, indicating that ARID5B regulates AR transcription. The active histone mark, H3K4me3, occupancy was decreased with ARID5B knockdown. Conclusion Our study revealed that AR transcription is positively regulated by ARID5B through H3K4me3 recruitment in the AR promoter. Our findings reveal novel mechanisms of AR transcription, which is dynamically regulated in prostate tumor progression.

We assessed the properties of biofilms (BFs) formed by mono- and co-cultures of Listeria monocytogenes and Pseudomonas aeruginosa (L+P-BF) at low temperatures and examined their sensitivity to several antibacterial substances. L. monocytogenes viable counts comprised only 1-10% of total L+P-BF viable counts at 10℃ and 15℃, indicating the significant prevalence of P. aeruginosa in co-cultures. L+P-BF formed at 10℃ and 15℃ showed very high resistance to antibiotics and NaClO. Examination of the effects of nattokinase and nisin, natural food additives with antibacterial properties, showed that their application alone failed to inhibit L+P-BF development at 10℃ and 15℃. However, a combined treatment with nisin and ethylenediaminetetraacetic acid, a food additive that can be used as a permeabilizing agent, suppressed the formation of L+P-BF at 10℃ and 15℃. Microscopy observations of L+P-BF did not reveal pronounced morphological changes in bacterial cell morphology. We also noted that P. aeruginosa resistance to the action of nisin during BF formation was higher when it was maintained in co-culture with L. monocytogenes. The results of the present study are an important step toward developing a safe formulation of acceptable food additives that could be used for suppression of BFs formed by pathogenic bacteria during food storage.

To express cellular phenotypes in organisms, living cells execute gene expression accordingly, and transcriptional programs play a central role in gene expression. The cellular transcriptional machinery and its chromatin modification proteins coordinate to regulate transcription. To analyze transcriptional regulation at the molecular level, several experimental methods such as electrophoretic mobility shift, transient reporter and chromatin immunoprecipitation (ChIP) assays are available. We describe a modified ChIP assay in detail in this article because of its advantages in directly showing histone modifications and the interactions between proteins and DNA in cells. One of the key steps in a successful ChIP assay is chromatin shearing. Although sonication is commonly used for shearing chromatin, it is difficult to identify reproducible conditions. Instead of shearing chromatin by sonication, we utilized enzymatic digestion with micrococcal nuclease (MNase) to obtain more reproducible results. In this article, we provide a straightforward ChIP assay protocol using MNase.

We assessed the properties of biofilms (BFs) formed by mono- and co-cultures of Listeria monocytogenes and Pseudomonas aeruginosa (L+P-BF) at low temperatures and examined their sensitivity to several antibacterial substances. L. monocytogenes viable counts comprised only 1-10% of total L+P-BF viable counts at 10℃ and 15℃, indicating the significant prevalence of P. aeruginosa in co-cultures. L+P-BF formed at 10℃ and 15℃ showed very high resistance to antibiotics and NaClO. Examination of the effects of nattokinase and nisin, natural food additives with antibacterial properties, showed that their application alone failed to inhibit L+P-BF development at 10℃ and 15℃. However, a combined treatment with nisin and ethylenediaminetetraacetic acid, a food additive that can be used as a permeabilizing agent, suppressed the formation of L+P-BF at 10℃ and 15℃. Microscopy observations of L+P-BF did not reveal pronounced morphological changes in bacterial cell morphology. We also noted that P. aeruginosa resistance to the action of nisin during BF formation was higher when it was maintained in co-culture with L. monocytogenes. The results of the present study are an important step toward developing a safe formulation of acceptable food additives that could be used for suppression of BFs formed by pathogenic bacteria during food storage.

Three new compounds, i.e. 1-[2-(5-hydroxymethyl-1H-pyrrole-2-carbaldehyde-1-yl)ethyl]-1H-pyrazole (1), 1-({[5-(α- d -galactopyranosyloxy)methyl]-1H-pyrrole-2-carbaldehyde-1-yl}-ethyl)-1H-pyrazole (2), and (4-hydroxyphenyl)methanol 4-[β- d -apiofuranosyl(1→2)-O-β- d -glucopyranoside] (3), were isolated from an extract of watermelon seeds. Compounds 1 and 2 were pyrazole-alkaloids with a pyrrole ring. This is the first study to show compounds with pyrrole and pyrazole rings in a molecule isolated from natural products. In the evaluation for melanogenesis inhibitory, compound 1 exhibited modest inhibitory activity on melanogenesis without cytotoxicity. Meanwhile compound 2 showed some inhibitory activity accompanied by some cytotoxicity.

This study demonstrated that ARID5B mRNA is present in mouse cardiomyocyte HL-1 cells, and that ARID5B siRNA constantly knocked down ARID5B gene expression to the 40% level of control. AMPKα2 protein was elevated in such ARID5B knockdown HL-1 cells, and this was accompanied by an increase in the level of phosphorylated AMPKα. Since AMPKα2 mRNA levels did not change in ARID5B knockdown cells, the stability of AMPKα2 protein was investigated using inhibitors for protein synthesis and proteasomal degradation. Treatment of HL-1 cells with either cycloheximide or MG132 caused an appreciable increase in the amount of AMPKα2 protein in ARID5B knockdown cells, which suggests that knockdown of ARID5B mRNA extends the half-life of AMPKα2 protein in HL-1 cells via yet unidentified mechanisms. As for the expected downstream consequences of AMPKα2 activation, we found thus far that glucose uptake, fatty acid uptake, or fatty acid oxidation remained unchanged in HL-1 cells after knockdown of ARID5B. Further studies are required to understand the mechanisms for ARID5B knockdown and resulting AMPKα2 activation, and also to identify which metabolic pathways are affected by AMPKα2 activation in these cells. In summary, this study provided the foundation for an in vitro cell culture system to study possible roles of ARID5B in cardiomyocytes.

The ability of heated scallop-shell powder (HSSP) to work against Listeria sp. biofilm formed at a low temperature was investigated. A biofilm of L. innocua ATCC 33090 was grown on a glass plate at 15˚C for 15 days, then immersed in HSSP slurry. Following treatment, the disinfection ability of the HSSP against the biofilm was non-destructively quantified by conductimetric assay. The biofilm grown at 15˚C was less sensitive than that grown at 37˚C to HSSP treatment and alkaline treatment. The biofilm grown at 15˚C was completely deactivated by 30 min of HSSP treatment (10 mg/mL, pH 12.5). In contrast, after 30 min treatment with alkaline solution at pH 12.5 or sodium hypochlorite (100 ppm), the activity was reduced by only one order of magnitude. The disinfection efficacy of HSSP (10 mg/mL) against L. innocua is similar to or higher than that of sodium hypochlorite (200 ppm). Fluorescence microscopy validated the results of the conductimetric assay. Therefore, HSSP treatment is a potentially powerful alternative control agent against Listeria sp. biofilms that present hazards in the food industry.

Previous clinical study showed that aged garlic extract (AGE) has a preventive effect of vascular calcification in patients with coronary artery diseases. It has been reported that vascular smooth muscle cells (VSMC) and inflammatory cells including macrophages and lymphocytes migrate to sub-intimal region where atherosclerotic plaques are formed, and VSMC can differentiate into osteoblast-like cells, which are represented by the induction of alkaline phosphatase (ALP). We found that primary human coronary artery smooth muscle cells (HCASMC) showed the increased ALP activity, when cultured in the medium containing ascorbic acid, β-glycerophosphate, dexamethasone (IM), and supplemented with conditioned medium from macrophages (MCM). Then we tested the effect of AGE subdivided fractions and several compounds found in AGE, and then found that ((+)-(2S,3R)-Dehydrodiconiferyl alcohol, a dilignol compound existed in hydrophobic fraction of AGE, inhibited ALP activity in HCASMC.

The effect of chain end groups on the drying of phase separating polymer blends was investigated for different functionally terminated poly(dimethyl siloxane) (PDMS). The drying rates of a PDMS/cellulose acetate butyrate (CAB) blend in methyl ethyl ketone (MEK) or isopropyl acetate (IA) were measured using the gravimetric method. The weight loss curves revealed that the addition of dihydroxyl-terminated PDMS significantly increased the drying rate in a particular range of solvent concentrations. On the contrary, monoglycidyl-ether-terminated and monohydroxyl-terminated PDMS showed suppressed evaporation and particular transitions between suppressed and enhanced drying modes, respectively. The drying enhancement was especially observed in cases where the separating polymer domains were developed through a film, regardless of the surface activities of PDMS. These facts imply that the interfaces between the domains act as diffusion paths for solvent molecules, and thus guide the transportation of solvent from the interior to the surface.

The ability of heated scallop-shell powder (HSSP) to work against Listeria sp. biofilm formed at a low temperature was investigated. A biofilm of L. innocua ATCC 33090 was grown on a glass plate at 15˚C for 15 days, then immersed in HSSP slurry. Following treatment, the disinfection ability of the HSSP against the biofilm was non-destructively quantified by conductimetric assay. The biofilm grown at 15˚C was less sensitive than that grown at 37˚C to HSSP treatment and alkaline treatment. The biofilm grown at 15˚C was completely deactivated by 30 min of HSSP treatment (10 mg/mL, pH 12.5). In contrast, after 30 min treatment with alkaline solution at pH 12.5 or sodium hypochlorite (100 ppm), the activity was reduced by only one order of magnitude. The disinfection efficacy of HSSP (10 mg/mL) against L. innocua is similar to or higher than that of sodium hypochlorite (200 ppm). Fluorescence microscopy validated the results of the conductimetric assay. Therefore, HSSP treatment is a potentially powerful alternative control agent against Listeria sp. biofilms that present hazards in the food industry.

More realistic simulation of a possible earthquake is crucial for making a rational counter plan against earthquake disaster. This paper proposes such a simulation system, called Integrated Earthquake Simulator (IES), which combines various numerical simulations of earthquake and structure behaviors with data stored in geographical information system (GIS). The key simulation of IES is to achieve high resolution of strong ground motion (SGM), even though some ambiguity remains in modeling the ground structures due to lack of available data. Examined is the validity of numerical simulation of SGM, which takes advantages of stochastic modeling of the ambiguity. Once high resolution of SGM is achieved, all structures within a target area are modeled by using the GIS data, such that a digital city is constructed in computer. Examples of such a digital city and its earthquake disasters are computed by using a prototype of IES.

Our NRUSM (non-resonant type ultrasonic motor) driven 300 mm stroke precision stage for LSI manufacturing devices has achieved 0.69 nm control resolution and positioning performances. The results reveal the quick-response high-tracking ability of the NRUSM due to the piezoelectric effect. The sub-nanometer order physical displacement is totally controlled by the applied voltage. Although an extra precise positioner was needed for long stroke and high velocity conventional magnetic motor driven stages to achieve nanometer positioning, our actuator enables the stage to achieve high feeding velocity and high accuracy positioning simultaneously. The NRUSM is composed of 8 stack-type piezoelectric actuators, and by applying the appropriate control sequence infinite feeding becomes possible.

With the aim of increasing the mechanical strength of doped lanthanum gallate ceramics, which can be applied to the electrolyte in solid oxide fuel cells for reduced temperature operation, the effects of alumina dispersion on mechanical and electrical properties were investigated. The thermal expansion coefficient showed no significant changes either with the amount of alumina addition or with the oxygen partial pressure in the atmosphere. The alumina dispersion preferably along grain boundaries was found to be effective in retarding the grain growth of lanthanum gallate, which greatly increased the bending strength at both room temperature and 800°C. The sample with 2 wt% of alumina addition showed electrical conductivity comparable to that of the perovskite matrix alone at 800°C and higher conductivity at temperatures lower than 750°C. At additions of ≥5 wt%, the alumina grains partially blocked the transport of oxide ions between the lanthanum gallate grains, which decreased the ionic conductivity to unacceptable levels. The optimum alumina addition for the improvement of mechanical properties without altering the thermal expansion coefficient and ionic conductivity was found to be around 2 wt%. A single-cell using the electrolyte sheet with the optimized composition showed a maximum power density of 0.245 W/cm2 at 800°C.

A new-type porous strucutre, named ‘KAMINARI-OKOSI’ struture, was succesfully prepaerd utilizing both aquaous gel-casting slurry and resin filter and measured their pore size distribution, air permiability, bending strength and electrical conductivity. The slurry compositon contained pore former such as carbon, nickel caobonate to induce relatively small pore in calcinated body. On the other hand, a resin filter immersed into the slurry also acted as an another pore former and left relativery large pore after calcination. By the contribution of these two different vanishing materials, obtained porous body was consist of large porous sphericals bonding together and realized a bi-modal open-pore size distribution showing relatively large size pore (around 10 × 10-6m) and ordinary size pore (around 10-6m). After reduction at 1073K in H2, Ni/YSZ cermets having the ′KAMINARI-OKOSI′-type structure were allowed to high air permiability, and which made possible to fire at high temperature and to obtain high bending strength. This porous body having ′KAMINARI-OKOSI′-type structure was combined with a porous body having conventional porous structure, named ′KARUME-YAKI′-type one, to make thin YSZ electrolyte layer on the surface of porous body with ease and form a number of 3-phase interface site as active catalytic points. Splendid characteristics of the porous body combined ′KAMINARI-OKOSI′-type and ′KARUME-YAKI′-type structure in ratio of 6:4 by thicness were obtained as follows: air permiability of around 10-7m4·kg-1·Sec-1 at room temperature, 3-point bending strength of 34 MPa at room temperature and electrical conductivity of around 104S. m-1 at 1073K.

Two new cucurbitane-type triterpenes, 24-hydroperoxycucurbita-5,25-dien-3β-ol (1) and 25-hydroperoxycucurbita-5,23-dien-3β-ol (2), were isolated from a MeOH extract of Citrullus lanatus seeds. Compounds 1 and 2 exhibited moderate cytotoxic activities with IC50 values of 33.4–52.4 μM against HL-60 (human leukemia), P388 (murine leukemia), and L1210 (murine leukemia) cells. Compound 1 showed melanogenesis inhibitory activity (melanin content 80.0 %) with low cytotoxicity (cell viability 97.6 %) at a low concentration (10 μM).

The mechanism of shrinkage during sintering was investigated on PZT ceramics. Nb2O5 and MnO was added to PZT calcined powder. The mechanism of shrinkage was determined from the shrinkage-time curves. The mechanism of shrinkage and grain growth changed depending on the Nb2O5/MnO ratio. The dominant mechanism was volume diffusion when the Nb2O5/MnO ratio was larger than 6. On the other hand, the volume diffusion was inhibited when the Nb2O5/MnO ratio was less than 4. The grain growth was inhibited in the former conditions, while it was promoted in the latter conditions.

It has been reported by our previous paper on the sintering behavior of lead zirconate titanates (PZT) that additive MnO promotes the grain growth and suppresses the densification of PZT. This paper reports the sintering behavior of PZT with various amount of additive MnO and Sb2O3. Additive MnO promotes the grain growth of PZT, while additive Sb2O3, supresses the grain growth even with additive MnO together. It was found, however, that Sb2O3 acts as a sintering aid in the case of sintering PZT with 0.5 mass% Sb2O3 at 1100°C: this condition attains the maximum density of all the specimen. It also revealed that the grain boundary diffusion is dominant in PZT with no additive or with only MnO, and that volume diffusion is dominant in PZT with only Sb2O3 or the both of Sb2O3 and MnO.

The effect of Ag and PbO on the sintering behavior and the piezoelectric properties of PbSr(Mg1/3Nb2/3)O3-PbZrO3-PbTiO3 system has been studied. A small addition of Ag enhances the value of er. and Kr. In the specimen with Ag addition, the grain growth was observed by use of SEM. The shrinkage vs temperature curves showed that the shrinkage of the specimen with Ag addition abruptly increases from 900°C and the value of shrinkage at 1100°C is as twice as the additive-free specimen. The shrinkage vs time plots revealed that the grain boundary diffusion is dominant on the sintering of PMN-PZT with Ag and Pb addition.

The influence of MnCO3 addition on the sintering behaviour of PZT ceramics was investigated. In proportion as amount of MnCO3 addition increased, the relative density of sintered body decreased. The shrinking curves during sintering showed the following features ; Starting temperature of shrinking shifted higher as amount of MnCO3 addition increased. These shrinkages were able to classify into two stages;at the first stage, the shrinking speeds of specimen were relatively slow, but at the second stage, those were rapid. Achieved shirinkage values of each specimen were corresponding to the relative densities. The grain growth behaviour was investigated with SEM micrographs. On the specimen with 0.4wt% MnCO3, rapid grain growth occurred only between 1050°C and 1150°C, but slow grain growth continued over 1150°C.On the specimen with 0.8wt% MnCO3, grain growth did not occured till 1150°C, but rapid grain growth continued over 1150°C. We conclude that the MnCO3 is not useful for PZT ceramics as a sintering aid.

Mice lacking modulator recognition factor-2 (Mrf-2; ARID5B) have less fat in brown and white adipose tissues, partly because of a defect in adipocyte differentiation. We have also shown that knockdown of Mrf-2 decreases the expression of the adipogenic transcription factors C/EBPalpha and PPARgamma, and inhibits adipogenesis in 3T3-L1 preadipocytes. Since these transcription factors may also contribute to the maintenance of adipocyte function, we examined the effects of siRNA targeted to Mrf-2 on triglyceride metabolism in mature 3T3-L1-derived adipocytes. As it did in differentiating adipocytes, knockdown of Mrf-2 decreased the expression of both C/EBPalpha and PPARgamma. Knockdown of Mrf-2 also activated both lipolysis and triglyceride synthesis, and caused a significant increase in the ratio of glycerol release to free fatty acid release. This suggests that knockdown of Mrf-2 increases the rate of fatty acid recycling in 3T3-L1-derived adipocytes. Continual cycling of fatty acids through lipolysis and triglyceride synthesis could lead to dissipation of energy. Therefore, the activation of such a futile cycle via the suppression of Mrf-2 could be an effective treatment for obesity and diabetes.

Previous study showed that mice lacking modulator recognition factor-2 (Mrf-2) were lean, with significant decreases in white adipose tissue. One postulated mechanism for the lean phenotype in Mrf-2 knockout mice is a defect in adipogenesis. In order to investigate this further, we examined the effects of Mrf-2 deficiency on adipogenesis in vitro. In mouse fibroblasts (MEFs) derived from Mrf-2(-/-) embryos, and in 3T3-L1 cells after knockdown of Mrf-2 by small interference RNA (siRNA) there was a potent inhibition of hormone-induced lipid accumulation, and significant decreases in the expression of the adipogenic transcription factors CCAAT/enhancer-binding protein (C/EBP) alpha and peroxisome proliferator-activated receptor-gamma and the mature adipocyte genes they control. Transduction of Mrf-2(-/-) MEFs with a retroviral vector expressing the longer Mrf-2 splice variant (Mrf-2B) stimulated both gene expression and lipid accumulation. Because 3T3-L1 cells are committed to the adipocyte lineage, we used this simpler model system to examine the effects of Mrf-2 deficiency on adipocyte maturation. Analyses of both mRNA and protein revealed that knockdown of Mrf-2 in 3T3-L1 cells prolonged the expression of C/EBP homologous protein-10, a dominant-negative form of C/EBP. Consistent with these findings, suppression of Mrf-2 also inhibited the DNA-binding activity of C/EBPbeta. These data suggest that Mrf-2 facilitates the induction of the two key adipogenic transcription factors C/EBPalpha and peroxisome proliferator-activated receptor-gamma indirectly by permitting hormone-mediated repression of the adipogenic repressor C/EBP homologous protein-10.

Precise positioning, which is the base technology for ultra-precise treatments, is highly essential in semiconductor LSI circuits, bio-cells, molecular sensors, and quantum devices. Conflicting performances, high-speed, long-stroke, and high-resolution have been achieved by using die nonresonant ultrasonic motor (NRUSM) controlled under the piezoelectric effect. One of the notable features of the NRUSM is do the frequency of the driving voltage can be varied in a wide range, which means the motion control of the NRUSM can be done by both the amplitude and frequency The maximum stage feed velocity is 140 mm/s with average acceleration of 2200 mm/s/sup 2/ in the 100 mm stroke under open-loop control. 100 nm step response with /spl plusmn/0.69 nm positioning accuracy is completed in 0.35 s under closed-loop control.

1,2,3,4-Tetrahydroisoquinoline (TIQ) and 1-benzyl-1,2,3,4-tetrahydroisoquinoline (1BnTIQ), which exist in the brain of several mammalian species, are parkinsonism-inducing substances, and 1-methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ), which is enzymatically synthesized in rat brain, is a parkinsonism-preventing substance. In this study, we examined the regional distribution of contents of TIQ, 1MeTIQ, and 1BnTIQ, and activity of 1MeTIQ-synthesizing enzyme in monkey brain. The TIQ and 1BnTIQ contents in cerebrum and substantia nigra, and the 1MeTIQ contents in striatum and substantia nigra were higher than those in other brain regions, and 1MeTIQ-synthetic activity was high in cerebrum and thalamus. We speculate that 1MeTIQ-synthesizing enzyme may play an important role in idiopathic Parkinson's disease.

The content of the endogenous amine, 1-methyl-1,2,3,4-tetrahydroisoquinoline (1-MeTIQ), in mouse brain, treated with the antipsychotic agent haloperidol (HP) was determined by GC-SIM (selected ion monitoring) system. 1-MeTIQ in brain was extracted with chloroform at pH 11-12 and was detected as PFP derivative by GC-SIM. The 1-MeTIQ contents in mouse brains following intraperitoneal administration of HP or its dehydrated product, HPTP (1 and 4 mg/kg per day, for four days), were markedly reduced compared with control groups. This result agrees well with the findings in human idiopathic parkinsonianism and in MPTP-treated mouse brain. In addition, this finding suggests that the change of the endogenous amine 1-MeTIQ content in the brain plays an important role in the pathogenesis of toxin-induced parkinsonism.

1-Methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ), an endogenous parkinsonism-preventing substance, is enzymatically synthesized from 2-phenylethylamine (PEA) and pyruvate. We investigated whether exogenous or endogenous parkinsonism-inducing compounds inhibit 1MeTIQ biosynthesis in a crude enzyme fraction from rat brain. Several parkinsonism-inducing compounds, including tetrahydroisoquinoline derivatives, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 1-methyl-4-phenylpyridinium (MPP + ), β -carboline and haloperidol, inhibited 1MeTIQ biosynthesis. The IC 50 value of MPP + for this enzyme is about 10 μ M, lower than that for inhibition of mitochondrial complex I. We propose that the parkinsonism-inducing action of these compounds is at least partly due to inhibition of 1MeTIQ biosynthesis.

An endogenous parkinsonism-preventing substance, 1-methyl-1,2,3,4-tetrahydroisoquinoline, is enzymatically formed from 2-phenethylamine and pyruvate in rat brain. The enzyme involved was localized in the mitochondrial-synaptosomal fraction of rat brain, solubilized by treatment with sodium deoxycholate. In order to purify the enzyme, gel filtration was carried out. This enzyme may be important in the pathogenesis of Parkinson's disease.

A highly reliable nonresonant ultrasonic motor (NRUSM) made of cylindrical piezoelectric material is proposed in this paper. The high reliability is characterized by long lifetime and no outer gas in the vacuum environment, which are ensured by not using stack adhesives as the source of the gas emission. Positioning and tracking accuracy was better than below ±2 nm. The structural design is discussed in terms of the application to a high-speed high-precision stage system which has stable response to frequent biases without interference from resonant phenomena and the required mechanical strength.

Single crystals of yttria partially stabilized and yttria fully stabilized zirconia with the composition YxZr1−xO2−x/2 (x = 0.02-0.30) were grown from the melt by xenon arc image floating zone method. The crystals are 3–4 mm in diameter and 150 mm in length. Crystals with low yttria content tended to bend or develop cracks on cooling and those with high yttria content were straight and had no cracks. The microstructures of the crystals were analysed by TEM, SEM and XRD. Chemical etching of the crystal with hot phospheric acid preferentially dissolved the matrix phase in comparison with the precipitate phase. The SEM photographs of the etched surface showed microstructural images closely related to those observed by TEM.