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A 57 Fe nucleus in the solar core could emit a 14.4-keV monochromatic axion through the M1 transition if a hypothetical elementary particle, axion, exists to solve the strong CP problem. Transition edge sensor (TES) X-ray microcalorimeters can detect such axions very efficiently if they are again converted into photons by a 57 Fe absorber. We have designed and produced a dedicated TES array with 57 Fe absorbers for the solar axion search. The iron absorber is set next to the TES, keeping a certain distance to reduce the iron-magnetization effect on the spectroscopic performance. A gold thermal transfer strap connects them. A sample pixel irradiated from a 55 Fe source detected 698 pulses. In contrast to thermal simulations, we consider that the pulses include either events produced in an iron absorber or gold strap at a fraction dependent on the absorption rate of each material. Furthermore, photons deposited on the iron absorber are detected through the strap as intended. The identification of all events still needs to be completed. However, we successfully operated the TES with the unique design under iron magnetization for the first time. [ABSTRACT FROM AUTHOR]

This study attempted to develop detection methods for solar axions using transition-edge-sensor (TES) microcalorimeters. Since the axion absorber comprised of iron-57 (57Fe) is electroplated upon the membrane instead of directly onto the TES itself (with the absorber hence thermally connected to the TES via a gold thermal strap), some of the heat deposited into the absorber consequently escapes into the heat bath through the membrane before being detected by the TES. If the heat-loss depends upon the axion interaction position within the absorber, position dependence may degrade the energy resolution. Therefore, this study endeavored to evaluate the dependence of heat-loss and pulse shape on axion incident position with the COMSOL Multiphysics software package (using a finite element method). In addition, heat-loss and pulse shape were likewise evaluated when the energy was deposited directly within the gold thermal strap. [ABSTRACT FROM AUTHOR]

We have developed a four-pixel array of superconducting transition-edge sensors with gold absorbers for the detection of a 29.2 keV γ -ray doublet decay from 229 Th. To identify the decay, an energy resolution better than 20 eV full width at half maximum (FWHM) is needed. We measured an energy resolution of 14 eV FWHM for 26 keV γ -ray decay from an 241 Am isotope in combined data of three pixels. We describe the design and the performance of the devices and discuss the baseline correction method to compensate the variation in the baseline, which was observed during the evaluation of the performance using the 241 Am isotope. [ABSTRACT FROM AUTHOR]

Several issues in developing transition edge sensor (TES) microcalorimeters for the search of monochromatic solar axions expected at 14.4 keV are studied. The potential problem of developing TES's of this purpose is in that an axion absorber of 57 Fe must be placed in close vicinity of a TES. We estimated the minimum distance to avoid magnetic interference from iron using magnetic FEM simulations, and found it 30 μ m for an iron of 5 μ m thickness. We fabricated a TES with a 10 μ m thick iron membrane separated by 60 μ m. We confirmed the superconducting transition for this TES. However, both the residual normal resistance and the transition temperature was different from those of TES without iron. We also estimated the low-temperature thermal conductivity of an iron membrane by measuring the low-temperature electrical resistance and by applying the Wiedemann–Franz law. We estimated the pulse-shape dependency on the interaction position within the 57 Fe converted using thermal FEM simulations. We found that the pulse-shape variations will limit the energy resolution to about 30 eV FWHM. [ABSTRACT FROM AUTHOR]

We investigated the pressure coefficients of the superconducting order parameters at the ground state of ferromagnetic superconductors based on the microscopic single band model by Linder et al. The superconducting gaps (i) similar to the ones seen in the thin film of A2 phase in liquid He and (ii) with the line node were used. This study shows that we would be able to estimate the pressure coefficients of the superconducting and magnetic order parameters at the ground state of ferromagnetic superconductors. [ABSTRACT FROM AUTHOR]

A part of d-amino-acid oxidase gene was amplified in the human and mouse by polymerase chain reaction. The amplified fragments were ligated to plasmids and then cloned. The plasmids containing the parts of d-amino-acid oxidase gene were biotinylated and hybridized to human and mouse metaphase chromosomes. The chromosomal slides were treated with fluorescein isothiocyanate (FITC)-conjugated avidin. The hybridized signals were amplified with biotinylated anti-avidin antibody and FITC-avidin. The chromosomes were counter-stained with diamidino-phenylindole for assignment of the signal to a specific band. Using this fluorescence in situ hybridization (FISH), d-amino-acid oxidase gene was assigned to human chromosome 12q23–24.1 and mouse chromosome 5E3-F. Since these regions are syntenic between human and mouse, the present results indicate that the locus for this enzyme has been conserved through evolution. [ABSTRACT FROM AUTHOR]

A cell line (R-Y121B·DF) has been established from a cell line (R-Y121B) derived from a rat hepatoma line (H4-II-E). The R-Y121B·DF cells have been continuously cultured in a serum-free modified Eagle's minimum essential medium in which l-phenylalanine was replaced by d-phenylalanine. They had d-amino-acid oxidase (DAO) activity which is essential for the growth in the medium containing d-amino acids. The enzyme activity of the R-Y121B·DF cells was approximately one-fourth of that of the rat liver. Northern hybridization using a DAO cDNA probe detected a hybridizing signal in the R-Y121B·DF cells and the rat liver but not in the parental R-Y121B and H4-II-E cells. Reverse transcription-polymerase chain reaction using DAO-specific primers amplified a DNA fragment of the expected size in the R-Y121B·DF cells but not in the R-Y121B and H4-II-E cells. This fragment was confirmed to be DAO cDNA by nucleotide sequencing. Western blotting showed that DAO protein was present in the R-Y121B·DF cells and the rat liver but not in the R-Y121B and H4-II-E cells. Southern hybridization showed that the DAO gene structure was not different among the R-Y121B·DF cells, R-Y121B cells, H4-II-E cells, and the rat liver. These results indicate that the R-Y121B·DF is a unique cell line which proliferates in the medium containing d-phenylalanine and explicitly expresses DAO. This line is useful for the study of DAO in vitro. [ABSTRACT FROM AUTHOR]

Human epithelial ovarian carcinoma is well-known as a sex steroid-dependent neoplasm, but the possible biological significance of progesterone receptor (PR) in this cancer remains controversial. Recently, two isoforms of human PR, PRA and PRB, have been characterized and different functional characteristics have been reported for these two isoforms. We therefore examined immunohistochemistry (107 cases) and reverse transcription-polymerase chain reaction (RT-PCR) (16 cases) for PRA, PRB, and oestrogen receptor-a (ER-a). Labeling indices (LI) for PRA and PRB were 2.4 and 43.6, respectively, and the difference was statistically significant. PRB LI, but not PRA LI, as well as performance status, stage, and residual tumour turned out to be independent prognostic factors following multivariate analysis. There was also a significant correlation between ER-a LI and PRB LI (r = 0.595, P < 0.0001), suggestive of a possible interaction between these two receptors. RT-PCR also detected the expression of PR isoform transcripts in the same pattern as was observed with immunohistochemistry. Results of these studies indicate that PRA and PRB both mediate distinct pathways of progesterone action in ovarian carcinoma. Moreover, it is important to examine PRB LI as a prognostic factor in the cases of human epithelial ovarian carcinoma. [ABSTRACT FROM AUTHOR]

When D-propargylglycine was injected intraperitoneally into mice, polyuria, glycosuria, and aminoaciduria were observed as has been previously reported in rats. The urine of the mice treated with D-propargylglycine contained twice as much protein as that of the control mice. Polyacrylamide gel electrophoresis showed a new protein of approximately 62 kDa in the urine of the D-propargylglycine-treated mice. Protein sequencing revealed that this protein was serum albumin. Since the above-mentioned symptoms suggested dysfunction of the renal proximal tubules, the activity of urinary N-acetyl-β-D-glucosaminidase, a marker enzyme of injury to the proximal tubules, was measured. The urinary enzyme activity was 2.6 times higher in the D-propargylglycine-treated mice than in the control mice. Light- and electron-microscopy showed degenerative and necrotic cells in the straight part of the proximal tubules of the treated mice. However, none of these symptoms was observed in D-propargylglycine-treated mutant mice, lacking D-amino-acid oxidase. These results indicate that D-propargylglycine itself is not nephrotoxic but its metabolite produced by the D-amino-acid oxidase reaction is nephrotoxic and injures proximal tubular cells, resulting in an impairment of the reabsorption of water, glucose, amino acids, and proteins. [ABSTRACT FROM AUTHOR]

Urine of ddY/DAO mice lacking d-amino-acid oxidase contained 5.7 times more serine than that of normal ddY/DAO+ mice. Most of the serine was d-isomer. The origin of thisd-serine was examined. Oral administration of 0.02% amoxicillin and 0.004% minocycline to the ddY/ DAO- mice for 7 days did not reduce the urinary d-serine, indicating that the d-serine was not of intestinal bacterial origin. When the mouse diet was changed to one with different compositions, the urinary d-serine was considerably reduced. Furthermore, starvation of the ddY/DAO- mice for 24 hours reduced the urinary d-serine to 33% of the original level. These results indicate that most of the urinary d-serine comes from the diet. However, the urine of the starved ddY/DAO- mice still contained 4.6 times more d-serine than that of the ddY/DAO+ mice, suggesting a part of the D-serine have an endogenous origin. [ABSTRACT FROM AUTHOR]

The rat R-Y121B cell line is a unique cell line which has ornithine carbamoyltransferase (OCT, EC 2.1.3.3) and can be continuously cultured in a serum-free medium which lacks arginine but is supplemented with ornithine. The OCT gene expression was examined in R-Y121B cells and their parental H4-II-E cells. OCT activity in R-Y121B cells was about one-tenth of that of the adult rat liver while it was not detected at all in H4-II-E cells. Southern hybridization using an OCT cDNA probe containing the entire coding region showed that the OCT gene structure was apparently not different in R-Y121B cells, H4-II-E cells, or rat liver cells. Northern hybridization using the OCT cDNA probe detected a hybridizing signal in R-Y121B cells but not in H4-II-E cells. Reverse transcription-polymerase chain reaction (RT-PCR) showed that an expected size of the OCT cDNA fragment was amplified in R-Y121B cells but not in H4-II-E cells. The amplified fragment was confirmed to be a real rat OCT cDNA by the digestion of this fragment with two restriction enzymes and by the nucleotide sequencing of the fragment. These results indicated that OCT mRNA was present in R-Y121B cells but not in H4-II-E cells. Amino acid analysis showed that arginine was not present in the culture medium but was present in the hydrolysate of R-Y121B cells. The present experiments indicate that transcription, translation, and processing of OCT proceeds normally and the resultant OCT functions in R-Y121B cells, whereas the transcription does not occur in parental H4-II-E cells even though these cells have the normal gene. [ABSTRACT FROM AUTHOR]

Genomic DNA was extracted from mice of 15 strains (A/J, AKR, BALB/c, C3H/He, C57BL/6, CBA/J, CD-1, CF#1, DBA/2, ddY/DAO, ddY/DAO, ICR, NC, NZB and NZW) for the examination of the difference in the structure of the d-amino-acid oxidase gene among the mouse strains. The DNAs were digested with restriction endonucleases and analyzed by Southern hybridization using d-amino-acid oxidase cDNA as a probe. The 15 strains showed the same hybridization patterns in the EcoRV, BamHI or BglII digestion. In the EcoRI digestion, the DBA/2 strain showed a different hybridization pattern from the other 14 strains. In the PvuII and XbaI digestion, C3H/He, CBA/J, ddY/DAO and NC strains were different from the other 11 strains. In the PstI and HindIII digestion, restriction fragment length polymorphisms were observed, and the 15 strains were classified into four groups according to their hybridization patterns. These results indicate that the 15 strains of mice carry a structurally similar d-amino-acid oxidase gene, but there is a variation in its inside sequence among the groups of the strains. [ABSTRACT FROM AUTHOR]

d-Amino acid oxidase cDNA was amplified by a polymerase chain reaction using RNA extracted from the mouse kidney. When digested with HindIII, the cDNAs of the BALB/c and ddY/DAO mice were cleaved into two fragments whereas the cDNA of the ddY/DAO mice was not. Sequencing revealed that nucleotide-471 of the cDNAs was G in the BALB/c and ddY/DAO mice whereas it was substituted for C in the ddY/DAO mice. This base substitution was the cause of the failure of the cleavage of the cDNA of the ddY/DAO mice. Examination of other strains of inbred mice showed that d-amino-acid oxidase cDNAs of A/J, AKR, C57BL/6, CD-1, CF#1, ICR, DBA/2, NZB and NZW mice were cleaved with HindIII into two fragments whereas those of C3H/He, CBA/J and NC mice were not. Genomic DNAs extracted from the mice of these 15 strains were digested with HindIII and hybridized with d-amino-acid oxidase cDNA. A 18.2-kb fragment hybridized with the probe in the C3H/He, CBA/J, ddY/DAO and NC mice whereas two fragments of 12 kb and 6.2 kb hybridized in the other mice. These results are consistent with those of the cDNAs, confirming the loss of the HindIII cleavage site in the C3H/He, CBA/J, ddY/DAO and NC mice. The Southern hybridization revealed a loss of a different HindIII cleavage site in the A/J, AKR, C57BL/6, DBA/2, ICR and NZB mice. The substitution at nucleotide-471 should cause a substitution of an amino acid residue. However, this substitution did not affect catalytic activity of d-amino acid oxidase. [ABSTRACT FROM AUTHOR]

Urine of mutant ddY/DAO mice lacking d-amino-acid oxidase activity contained more serine and proline than that of normal ddY/DAO mice. d-Amino-acid oxidase treatment of urinary amino acids decreased the serine and proline, suggesting that they contained d-isomers. An HPLC analysis confirmed the presence of d-serine. Urinary serine and proline contents were not decreased when the ddY/DAO mice were fed a diet which did not contain supplementary d-methionine or when they were given water containing antibiotics. These results suggest that the d-serine and d-proline do not derive from the d-methionine supplemented in the diet or from intestinal bacteria. In urine of the ddY/DAO mice, a substance which seemed to be d-methionine sulfoxide and/or d-methionine sulfone was present. It is probably a metabolite of the d-methionine supplemented in the diet. The d-aminoaciduria in the mutant mice lacking d-amino-acid oxidase activity indicates that this enzyme is involved in the metabolism of the d-amino acids in normal mice. [ABSTRACT FROM AUTHOR]

D-amino acid oxidase (DAAO) activity was not altered in the liver and kidney by oral administration of D-alanine to adult mice. The enzyme was apparently not induced by the enteric microflora either, since the enzyme activity in the liver and kidney of germ-free mice was not different from that of specific-pathogen-free mice. The times of appearance of DAAO activity and of free D-amino acids in the kidney were elucidated using suckling mice. DAAO activity started to increase 7 days after birth, and reached almost the adult level by 28 days. The content of free neutral D-amino acids also increased with age, in a similar fashion. A possible conclusion is that the enzyme activity normally increases during this period, to eliminate the free D-amino acids which have increased with age in the suckling mice. Consequently, the administration of D-alanine had no further effect in increasing enzyme activity. [ABSTRACT FROM AUTHOR]

A mutant mouse strain ddY/DAO lacks D-amino acid oxidase activity and accumulates free neutral D-amino acids in its tissues. In this study, D-aspartate oxidase activity and D-aspartate content in the tissues of these mutant mice were compared with those of normal mice. No significant difference was observed, indicating that the metabolism of acidic D-amino acids was unaffected in the mutant. [ABSTRACT FROM AUTHOR]

Carboplatin is a useful agent for the treatment of ovarian carcinoma. Anaphylactic reaction to carboplatin is rare, but it is an important adverse effect, as it is potentially life-threatening. We report a 48-year-old Japanese woman with stage IIIc (FIGO) serous cyst adenocarcinoma of the ovary who had an anaphylactic reaction after a total of ten courses of carboplatin chemotherapy. Premedication with steroid failed to prevent the anaphylactic reaction. She required resuscitation with oxygen, and treatment with intravenous fluid, hydrocortisone, and antihistamines. Because hypersensitivity reactions to carboplatin appear to become more frequent with repeated use, it is important to always be aware of possible anaphylactic shock in patients with persistent or relapsed ovarian cancer during the prolonged use of carboplatin. [ABSTRACT FROM AUTHOR]