Fatigue life estimation system for the fatigue crack growth numerical simulation code FLARP is under development. In order to offer the easy to use system for engineer, it is important to link with general-purpose FEM code. In the fatigue life estimation by FLARP, an equivalent distributed stress must be calculated and input to FLARP. In this paper, concept of the system and overview of the functions are introduced.

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In many cases, the fatigue crack initiates at the weld toe and propagate to plate thickness direction. To secure the structural integrity, it is important to estimate the crack initiation life and crack propagation rate. Fatigue tests on bead-on-plate welded specimen were carried out to investigate the crack initiation and propagation behavior. For predicting fatigue crack initiation and propagation, numerical simulation code "FLARP" based on ΔK_<RPG> was developed by Toyosada et al. In this paper, numerical simulations on fatigue tests are performed to verify the validity of numerical methodology of FLARP. It is confirmed that crack initiation life and propagation rate estimated by FLARP agree well with experimental results.

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Although a number of procedures have been proposed for the quantitative determination of pyridoxal () and that of pyridoxal 5'-phosphate (-P), it has been required to develop more reliable and simplified methods for the determination in biological materials.
Bonavita found that the reaction of and that of -P upon cyanide in an alkaline solution produced highly fluorescent cyanohydrins. The authors studied on the reactions of and -P on cyanide and devised a method for the determination of and -P in biological materials by means of these reactions.
Recently, Fukui et al. pointed out that the main reaction product of on cyanide was not -cyanohydrin [(II) in Fig.3] but 4-pyridoxolactone (PiAL) [(VI) in Fig.3] and that of -P was presumed to be 4-pyridoxic acid5'-phosphate.In our own experiments, similar results were obtained as to the reaction products by means of fluorescence and excitation spectra (Fig.1) and thin layer chromatography, and furthermore an intermediate compound [(III) in Fig.3] of the reaction of RAL on cyanide was isolated.The intermediate compound was quantitatively converted to PiAL in an alkaline solution in the presence of oxygen with liberation of cyanide ion. Its structure was determined by X-ray crystallography and the reaction mechanism was presumed to be as shown in Fig. 3.
4-Pyridoxic acid (PiA) is a metabolite of the vitamin B₆ group and it interferes with determination of and -P in biological materials by the present method. can be more easily separated from PiA than from -P and fluorescence intensity of the reaction product of was about 5 times as strong as that of -P, therefore -P was conveniently determined as by hydrolysis. Hydrolysis of -P was carried out by acid phosphatase partially purified from potatoes.
Determination of Sample was diluted with 0.2 M acetate buffer (pH 4.0) and deproteinized with 20% trichloroacetic acid (TCA). The deproteinized solution was placed on a column of Dowex IX 8 (5×80 mm, acetate form) and any interfering substances were removed by the column.The effluent from the column was passed through a column of Amberlite CG120 (5× 100 mm) which was previously bufferized to pH 4.0 with acetate buffer (pH 4.0). absorbed on the column was eluted with 0.4 M phosphate buffer (pH 7.5)(Fig.4) and treated with KCN. Fluorescence intensity at 430 mμ, excited at 356 mμ, was measured after being made alkaline with 0.4 M Na₂CO₃, and compared with the standards.
Determination of -P Sample was diluted with 0.2 M acetate buffer (pH 4.0) and heated at 80°C for 5 minutes. After cooling, acid phosphatase was added. It was incubated at 37°C for 1 hour and deproteinized with 20% TCA. Then it was treated as in the case of . The amount of -P was calculated by subtracting the amount of from the value obtained as above. In the case of -P, additional tests were carried out simultaneously and the determined value was corrected by recovery.
The results of recovery tests are shown in TABLE I. The present method is available to serum, plasma, urine and tissues.

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Changes in the blood B_6 levels after oral administration of pyridoxal 5'-n-butyrate (・NB), 5'-isobutyrate (・IB), 5'-benzoate (・BE), 3'-n-butyrate, 3', 4'-diacetate, 5'-acetate and 5'-succinate to rat were followed by fluorometric procedure. The maximum total concentrations were mostly the same as in the case of administration, but higher levels were maintained by 5'-acylates. In the case of ・NB, ・IB and ・BE, the areas under the time-blood concentration curve (AUC) were 1.5 times larger than that of administration. Possible hydrolysis of the 5'-acylates in the intestine was suggested in circulation experiments using rat intestine in situ and experiments with homogenate of the intestine in vitro. On the other hand, absorption of the 5'-acylates in their intact forms was also evidenced by fractional determination as well as bioautography using Sacch. carlsbergensis of the blood after administration of ・BE and ・NB. In this respect, these 5'-acylates were different from the reported pyridoxine acylate with longer chains. From these results, characteristics of 5'-acylation of molecule are discussed on the view point of drug latentiation and prolongation.

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The peptidoglycan-associated lipoprotein () is present in the cell envelope in a form closely, but not covalently, associated with peptidoglycan in various Gramnegative bacteria. When the cell envelope or the isolated peptidoglycan- complex from Proteus mirabilis, in which maintains the interaction with peptidoglycan, was digested with trypsin, a polypeptide fragment with molecular weight 11, 000 (11 K fragment) was obtained. However, when isolated or the 11 K-fragment which had been dissociated from peptidoglycan was treated with trypsin, they were further digested. The 11 K-fragment maintained essentially the same tight interaction with peptidoglycan as intact . These results indicate that the 11 K-fragment is probably derived from the peptidoglycan-associated region of the molecule. The purified 11 K-fragment contained neither covalently-linked fatty acid nor glycerylcysteine, which are known to be present at the N-terminus of . The N-terminal sequence of the 11 K-fragment was also determined.

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Antibody toward phenylalanine ammonia-lyase () [EC 4.3.1.5] was obtained by immunization of a rabbit with highly purified . The antibody reacted specifically with RAL, as demonstrated by the Ouchterlony double diffusion test, immuno-electrophoresis, and SDS polyacrylamide gel electrophoresis of the immunoprecipitate. Experiments using anti- showed that was not present in fresh sweet potato tissue, but appeared in response to cut injury, reaching a maximum, and then decreasing, in parallel with activity. The results suggest that the development of activity was due to de novo synthesis of and that the decrease of activity after reaching a maximum was due to proteolytic degradation of .

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The pectate lyase I ( I) gene was cloned from Erwinia carotovora Er. The cloned DNA, 5.1 kb, seemed to contain the region necessary for the regulation of pectin lyase formation, as I was induced by pectin in E. carotovora Er 18 containing the cloned I gene. I had a signal peptide of 22 amino acids which seemed to be cleaved between Gly and Ala. I had a M.W. of 37, 587 composed of 345 amino acids. The presence of promoter and SD sequences was suggested upstream of the translational start cod on of the I gene. A palindromic sequence, which might be important for the regulation of I gene expression, was detected downstream from the putative promoter. Another open reading frame highly homologous to the I gene was detected downstream from the I gene and designated the X gene. This gene had 81 % homology in 606 bp from the translational start codon with the I gene.

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In our previous study, aluminum matrix composites partly reinforced by SiC particles were fabricated by the imposition of a high frequency magnetic field to molten aluminum suspending SiC particles. The thickness of particle-accumulated layer () was almost the same as the skin depth that depends on the frequency of the magnetic field. In the present study, a 3 kHz magnetic field is applied to realize thicker . Although a 4.71 mm is expected at 3 kHz, is not formed because of a strong electromagnetic flow. Intermittent imposition of magnetic field is tested to increase , which seems effective to reduce the electromagnetic flow. A 4 mm with dense particle packing is realized by an intermittent magnetic field composed of 1 s imposition and 1 s pausing. Numerical calculation is performed to understand the behavior of metal flow with the intermittent magnetic field. It is found that 0.5 s is required for the development of metal flow. As the relaxation time of a single SiC particle in molten aluminum is far less than 0.5 s, can be formed before the metal flow develops.

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3'-or 5'-Substituted pyridoxal () derivatives were parenterally administered into rabbits and rats (10mg/kg) and the resultant B_6 levels in the blood and liver were determined. Among seven compounds tested, -5'-n-butyrate, 5'-isobutyrate and 5'-benzoate gave higher peak levels with larger biological half lives of blood total . On the intraveneous administration of these three compounds, the elimination process were specifically followed by a 2-phased first order kinetics though the reason of which was unexplained. Less lipophilic 5'-substitutes, 5'-acetate, 3', 4'-diacetate, 5'-succinate and 3'-n-butyrate gave similar B_6 levels to that of administration. 5'-acylates were confirmed to be hydrolyzed in the blood, mainly by a kind of plasma esterase. The esterase activity was somewhat different with animal species and the kind of substitutes. From these findings effects of 5'-acylation on the biopharmaceutical behavior of are discussed.

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A Simplified calculation method for thermal performance of the windows with frames used in non-residential buildings was proposed in this paper. The major difference of the proposed method from that used in the current (Perimeter Annual load) calculation is that it takes the thermal influence of frames into account.
Comparison calculations were undertaken between the conventional calculation (where the influence of frames was neglected) and the proposed calculation (where the influence of frames was taken into account).
As a result, it was examined that heating was smaller and cooling was larger by the proposed method. Moreover, in annual , it was confirmed that values changed according to the areas and the specifications of the windows and frames. It was shown that the influence of window frames couldn't be neglected in calculations.

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DJ-1 was identified as a causal gene for a familial form of early onset Parkinson’s disease (PD), park 7. DJ-1 plays roles in transcriptional regulation and the anti-oxidative stress reaction. In this study, we found that protocatechuic aldehyde (), a traditional Chinese medicine compound, bound to DJ-1 in vitro and that protected SH-SY5Y cells but not DJ-1–knockdown SH-SY5Y cells from oxidative stress–induced cell death, indicating that the protective effect of is mediated by DJ-1. Furthermore, inhibited production of reactive oxygen species and the inhibition was abated in DJ-1–knockdown cells. increased and decreased phosphorylation of AKT and PTEN, respectively, in SH-SY5Y cells, suggesting that the AKT pathway is one of the specific signaling pathways in -induced neuroprotection. Moreover, prevented superfluous oxidation of cysteine 106 of DJ-1, an essential amino acid for DJ-1’s function. The present study demonstrates that has potential neuroprotective effects through DJ-1.

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  In order to improve the mechanical properties of magnesium, dispersion strengthening with α-alumina particles () is experimentally investigated as an application of powder metallurgy. The trial process consists of milling, compacting and hot-pressing. The microstructure of hot-pressed discs of magnesium composites were investigated using optical microscopy, scanning electron microscopy, x-ray diffraction (XRD) and electron probe micro analysis. The density, surface hardness, and maximum bending stress for deflection were also measured. All of the mechanically alloyed (MA) prepared powders were composed of only magnesium (Mg) and alumina (Al₂O₃). Although the particle size of the MA powders varied, the mean values were approximately 80 μm and were approximately the half size of the raw Mg powder. Not only Mg powder, but also became finer with processing, and the was almost uniformly dispersed in the Mg powder. In addition, the fine was almost uniformly dispersed within the Mg of the dispersion strengthened (ODS) magnesium discs. For all discs, a small quantity of magnesium oxide (MgO) was identified along with Mg and Al₂O₃. However, in only the 22.7 vol% /Mg disc, an XRD peak assigned to an Al-Mg intermetallic compound (Al₁₂Mg₁₇) was detected, in addition to Mg, Al₂O₃ and MgO. It is proposed that Al₁₂Mg₁₇ was produced by the solid-state reaction of Mg and Al₂O₃, and appeared at the interface between the regions of only Mg and regions where is dispersed in Mg. The density of the discs was above the theoretical density for all content; the density for the highest content of 22.7 vol% was approximately 0.8 times greater than that of practical Al alloys. The 22.7 vol% disc had a maximum hardness value of 280 HV. This value is much higher than that of both pure Mg ingot and AZ91D. The maximum bending stress decreased with an increase in the content. The reason for this is considered to be that the discs become harder and more brittle, and voids are easier formed in the discs. Therefore, cracks that are generated on the specimen surface propagate easier.

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Incorporation of pyridoxal (), and its Schiff bases, oximes or 5'-acylates into red blood cells was investigated in vitro. Both influx and efflux of were found to be followed by a first order kinetics, and free aldehyde group in structure was essential to its rapid penetration into the cells. It was also suggested that 5'-acylates ( 5'-n-butyrate, 5'-isobutyrate, 5'-benzoate) are mostly adsorbed on the cell membrane. From these findings, process of incorporation of or its derivatives and their affinity to cell membrane are discussed.

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The inhibitory activity of flavonoids against L-phenylalanine ammonia-lyase [ ; EC 4.3.1.5] was systematically investigated. Twenty-three kinds of flavonoids were tested with three preparations of different origins. Quercetin (8) was found to be the most active among the flavonoids tested and inhibited all three preparations. Isoliquiritigenin (11), a biosynthetic intermediate of flavonoids, also showed relatively strong inhibition of . However, the chalcone deactivated in a time-dependent manner, and a model reaction with L-cysteine revealed that the chalcone formed an adduct with L-cysteine, indicating that is deactivated by the Michael type addition of chalcone. The results obtained in this study suggest that the inhibitory activity of flavonoids against does not occur by the mechanism of end product inhibition, as was suggested by Smith et al., but is merely a result of nonspecific deactivation of .

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Ultraviolet spectral studies of pyridoxal-homocysteine (-HCySH) in methanol were carried out at various media. The absorption bands were assigned and then the equilibria among the various molecular species in the methanol were found. Dissociation constants obtained by spectrophotometric method showed pKa_1=2.5,pKa_2=5.2,and pKb=2.8. Pyridoxal () is rapidly decomposed by exposure to light, particulary in neutral aqueous solution, while -HCySH is relatively stable in the solution. Photodecomposition of -HCySH would occur in the aqueous solution, because of the decomposition of produced by the hydrolysis. The decomposition would be avoided in methanol, though the was rapidly inactivated by exposure to light in alkaline methanol solution. and -HCySH in solid state were not decomposed by sunlight.

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遷延性肺瘻（Prolonged air leak；

）は，肺切除後に最も多く経験する術後合併症だが，術後早期にを予測することは容易ではない．2019年8月から2020年8月に当院で肺切除術後にデジタル式ドレナージシステムThopaz^Ⓡ（トパーズ）を用いた279例のうち， 7例を含む術後エアリークを認めた57例を対象とした．エアリークデータを後方視的に解析，術後早期に検出可能な予測因子を検討した．術後12時間に観察されたエアリーク量の最大値が800 mL/min以上の症例と，術後0から6時間までと術後6から12時間までのエアリーク量平均値の比が1.0以上の症例においてが有意に多かった（いずれもp＜0.001）．トパーズで検出される術後12時間のエアリーク量と経時変化は予測に有用であり，エアリークに対する治療介入を判断する指標となりうる．

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The antioxidant action of thiopalmitic acid (SH-) was studied in a lipid peroxidation system using microsomes from rat liver. The Fe (II)/ascorbic acid (AsA)-induced lipid peroxidation, as measured by the amount of thiobarbituric acid-reactive substances (TBA-RS), was progressively inhibited by the addition of increasing amounts of SH-. The inhibitory effect of SH- in this experimental system was greater than that of α-tocopherol, glutathione (GSH) and palmitic acid. The antioxidative effect was abolished gradually by the addition of increasing amounts of N-ethylmaleimide to the system. Similarly, microsomal lipid peroxidation induced by Fe (III)-ADP/NADPH or CCl₄/NADPH was inhibited in a dose-dependent fashion by the addition of SH-. Moreover, SH- was able to reduce 1, 1-diphenyl-2-picrylhydrazyl (DPPH). The α-tocopherol content of the microsomal lipid peroxidation system decreased rapidly when no SH- was present. However, upon adding SH- (90 μM), the decrease in the α-tocopherol content of the assay system was markedly reduced. These findings indicate that SH- acts as an antioxidant and free radical scavenger in lipid peroxidation carried out by rat liver microsomes.

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The excessive doses of 100 or 50mg/100g of pyridoxal-DL-homocysteine (-HCySH), pyridoxal hydrochloride (-HCl) and DL-homocysteine (HCySH) were administered to the rats fed with vitamin B_6-deficient diet during 6 weeks. Subacute lethalities, body weights and general toxic symptoms of the rats were observed. Amino acids in urine and plasma were determined, also. -HCySH has smaller toxicity than -HCl. Amino acids in 24 hours urine showed that taurine, cysteic acid were much larger than the others, in rats with administered -HCySH and HCySH. Cystathionine was excreted in urine of vitamin B_6-deficient rats, and did not change by an application of HCySH but disappeared by -HCySH or -HCl. HCySH in -HCySH molecule did not exist in the body, but it was changed to metabolite of the sulfur containing amino acids.

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