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We improved the critical current properties of fluorine-free metal organic decomposition processed YBCO thin films prepared on buffered metallic substrates by increasing the thickness of the films. YBCO films prepared using a conventional one-time growth exhibit a maximum Ic (77 K, ∼0 T) value of ∼100 A per 1 cm width for a film with a thickness of 0.8 μm, and Ic decreases with further increases in the film thickness due to the generation of impurity particles and micro-cracks. In this study, a multiple growth process was adopted for the preparation of thick films to avoid these problems. The Ic of films prepared using this method monotonically increased with the film thickness. YBCO films with a thickness of ∼3.0 μm recorded a quite high Ic (77 K, ∼0 T) value for ∼210 A cm−1 width. Additionally, the in-field Jcs at 20 K and 40 K were found to increase almost proportionally to the film thickness. [ABSTRACT FROM AUTHOR]

The Stokes geometry for the propagator of the quantum Hénon map is studied in the light of recent developments of the exact WKB analysis. As the simplest possible situation the Hénon map satisfying the so-called horseshoe condition is closely analyzed, together with listing up local bifurcation patterns of the Stokes geometry. This is exactly in the same spirit as pruning theory for the classical horseshoe system, and the present paper is placed as the first step to establish pruning theory of the Stokes geometry for chaotic systems. Our analysis reveals that the birth and death of the WKB solutions caused by the Stokes phenomenon do not occur in a local but entirely global manner, reflecting topological nature encoded in the Stokes geometry. We derive an explicit general formula to enumerate the number of WKB solutions in the asymptotic region and obtain its growth rate, which is shown to be less than the topological entropy of the corresponding classical dynamics. The relations to the diffraction catastrophe integrals and one-step multiply folding maps are also discussed. [ABSTRACT FROM AUTHOR]

Histone acetylation is one of the major mechanisms of epigenetic reprogramming of gamete genomes after fertilization or of transferred cell genomes after nuclear transfer to establish a totipotent state for normal development. In the fertilization of bovine oocytes, asynchronous histone acetylation occurs during pronuclear formation in the manner that modification of the paternal genome precedes that of the maternal genome (Wee et al. 2006 J. Biol. Chem. 281, 6048–6057). In the present study, the effects of trichostatin A (TSA), an inhibitor of histone deacetylase, during in vitro fertilization (IVF) of bovine oocytes on subsequent embryonic development were investigated. Cumulus-enclosed oocytes obtained from slaughterhouse ovaries were in vitro-matured (IVM) for 21 h in TCM-199 supplemented with 5% v/v FCS, 0.5 mM sodium pyruvate, 0.02 AU mL-1 FSH, and 1 g mL-1 estradiol-17? at 39C under 5% CO2 in air. After IVM, the oocytes were subjected to IVF with 3 106 mL-1 of Percoll gradient-selected sperm in a defined medium (Brackett and Oliphant 1975 Biol. Reprod. 12, 260–274) supplemented with 0 (control), 5, 50, and 500 nM TSA for 18 h. After IVF, presumptive zygotes were freed from cumulus cells and cultured in mSOF medium until 168 h post-insemination (hpi) at 39C under 5% CO2, 5% O2, and 90% N2 with high humidity. Cleavage and blastocyst development were assessed at 48 and 168 hpi, respectively. Inner cell mass (ICM) and trophectoderm (TE) of blastocysts were differentially stained by the method of Thouas et al. (2001 Reprod. Biomed. Online 3, 25–29) to assess cell number and ICM/TE ratio. Experiments were replicated 3 times. Data are presented as means SEM and statistically analyzed by multiple comparison with the Holm method. Rates of cleavage (0 nM: 71.0 7%, n = 102; 5 nM: 75.5 5%, n = 106; 50 nM: 68.8 6%, n = 105; and 500 nM: 71.7 4%, n = 98) and blastocyst formation (21.4 5%, 22.3 6%, 17.8 2%, and 18.2 2%, respectively) were similar among the groups. However, 500 nM TSA significantly (P < 0.05) increased ICM and total cell numbers (59.8 4 and 143.5 7, respectively, n = 31) compared with the control (43.1 3 and 120.9 7, n = 31). In addition, ICM/TE ratios were higher in the 50 nM (0.81 0.08, n = 29) and 500 nM (0.92 0.2, n = 31) groups than in the control (0.59 0.04, P < 0.05). These results suggest that TSA treatment during IVF of bovine oocytes does not affect the blastocyst rate but alters the cell numbers and their allocation to ICM and TE. Overriding epigenetic modification of the genome during fertilization may have a carryover effect on cell proliferation and differentiation in pre-implantation embryos.This study was supported by a grant from Wakayama Prefecture Collaboration of Regional Entities for the Advancement of Technological Excellence, JST. [ABSTRACT FROM AUTHOR]

Homocysteine is a nonessential amino acid produced through methionine metabolism. Elevation of homocysteine levels (hyperhomocysteinemia) increases intracellular S-adenosylhomocysteine (SAH). S-adenosylhomocysteine binds to methyltransferases (MT) with greater affinity than does S-adenosylmethionine, which is the universal methyl donor used by various cellular MT, including DNA and histone MT. Thus, SAH acts as a potent competitive inhibitor of methylation reactions. Therefore, disorder of homocysteine metabolism may affect cellular homeostasis in part through the process involving methylation reactions (Williams KT and Schalinske KL 2007 J. Nutr. 137, 311–314). Despite its predicted importance, the involvement of homocysteine metabolism in pre-implantation embryonic development remains unaddressed. In the present study, the expression of enzymes related to homocysteine metabolism in bovine pre-implantation embryos and the effects of homocysteine on the post-fertilization development of these embryos in vitrowere investigated. Cumulus-enclosed oocytes obtained from slaughterhouse bovine ovaries were in vitro-matured (IVM) for 22 h in modified synthetic oviduct fluid (mSOF) supplemented with 10% v/v FCS and 0.2 IU mL-1follicle-stimulating hormone. After IVM, the oocytes were subjected to IVF with Percoll gradient-selected sperm from one bull in an mSOF-based medium for 20 h. After IVF, presumptive zygotes were freed from the cumulus cells and cultured in mSOF up to Day 8 (IVF = Day 0). All cultures were performed at 38.5°C under 5% CO2, 5% O2, and 90% N2. Total RNA was extracted from individual blastocysts on Day 7 to 8 and reverse transcribed to cDNA using oligo(dT) primer. Transcripts for methionine adenosyltransferase 2A (MAT2A), MAT2B, adenosylhomocysteinase, methionine synthase, betaine-homocysteine MT, serine hydroxymethyltransferase 1, and 5,10-methylenetetrahydrofolate reductase were examined by qualitative PCR using bovine-specific primers for each gene and the cDNA as templates. β-Actin transcripts were used as an internal control. Moreover, presumptive zygotes after IVF were cultured in mSOF supplemented with 0 (control), 10, and 100 μmhomocysteine, and development to cleavage stage and blastocyst was assessed on Day 3 and Day 7 and 8, respectively. The cultures were replicated 4 times using 561 embryos. The development data were statistically analyzed by using the general linear model. Transcripts for all genes examined were detected. Homocysteine added to the culture medium of bovine IVF embryos did not affect the cleavage rate (86.8, 83.3, and 84.3% for control, 10 μm, and 100 μm, respectively); however, blastocyst rate significantly decreased (P= 0.02) on Day 7 (12.8, 9.3, and 7.5%, respectively). The blastocyst rate on Day 8 showed no difference (P= 0.33) among the groups (24.4, 20.4, and 20.1%, respectively). These results indicate that a system for homocysteine metabolism is present in bovine pre-implantation embryos and that high homocysteine levels affect the developmental kinetics of these embryos.Supported by KAKENHI. [ABSTRACT FROM AUTHOR]

In recent years a new description has been developed for tunnelling in multi-dimensional systems based on complexified stable-unstable manifolds of periodic saddles. The complexified stable-unstable manifolds guide complex-classical tunnelling trajectories over the energetic barrier (Takahashi and Ikeda 2003 J. Phys. A: Math. Gen. 36 7953). In this paper it is claimed, based on theoretical analysis and numerical evidence, that the tunnelling mechanism due to complexified stable-unstable manifolds is associated with a characteristic plateau feature in the tunnelling spectrum. An analysis of a particular two-dimensional barrier tunnelling model shows that the plateau feature is obtained by a fully quantum-mechanical computation, and that the complex-semiclassical theory successfully reproduces this feature. Moreover, an analytical theory based upon Melnikov's method is developed and used to clarify quantitatively how the tunnelling mechanism due to the complexified stable-unstable manifolds leads to the formation of the plateau structure; in particular, it is shown that the classical action along the complexified stable manifold controls the height of the plateau. The analysis presented here is based on a particular model, but the main claims should hold for any system with multi-dimensional barrier tunnelling because of the universality of the underlying mechanism. [ABSTRACT FROM AUTHOR]

We report a patient with primary anti-phospholipid syndrome (APS) who developed pulmonary edema following sudden-onset pain in the left, lower back of the chest. Radiological examinations demonstrated fresh infarction of the left adrenal gland but no obvious thrombi in pulmonary arteries. The patient quickly recovered from pulmonary edema with anti-coagulation therapy alone. Primary APS may have caused adrenal infarction in the patient, leading to transient pulmonary edema via microthrombosis and/or excessive release of catecholamine. [ABSTRACT FROM AUTHOR]

Abstract  The brain protein synthesis is sensitive to the dietary protein; however, the role of dietary protein on biomarkers including choline acetyltransferase and nerve growth factor (NGF) for the function of cholinergic neurons remains unknown in young rats. The purpose of this study was to determine whether the quantity and quality of dietary protein affects the concentration of NGF and activity of choline acetyltransferase, and their mRNA levels in the brains of young rats. Experiments were carried out on five groups of young rats (4 weeks) given the diets containing 0, 5, 20% casein, 20% gluten or 20% gelatin for 10 days. The activity of choline acetyltransferase in the cerebral cortex and hippocampus declined gradually with a decrease in quantity and quality of dietary protein. The concentration of NGF in the cerebral cortex and the mRNA levels of choline acetyltransferase in the cerebral cortex and hippocampus did not differ among groups. However, the concentration and mRNA level of NGF in the hippocampus was significantly lower in rats fed with lower quantity of protein or lower quality of protein. In the hippocampus, the mRNA levels of NGF significantly correlated with the NGF concentration when the quantity (r = 0.704, P r = 0.682, P r = 0.632, P r = 0.623, P  [ABSTRACT FROM AUTHOR]

Abstract   A high-sensitivity microwave-single-photon detector was developed in Kyoto, in which microwave photons in a resonant cavity cooled at very low temperatures are absorbed by highly excited Rydberg atoms and the Rydberg atoms thereby promoted to a higher excited state are then selectively field-ionized and detected. This scheme allows us to count microwave photons one by one, thus provide a single-photon counting without the limit of standard quantum limit (SQL). The apparatus “CARRACK” for the single-photon detector was constructed based on this scheme, where the cavity was cooled down to 10 mK range to reduce the background of thermal blackbody photons from the cavity wall. The apparatus has served for years to search for dark matter axions in the 10 μeV (∼2.4 GHz) mass region. Thermal blackbody photons in a microwave resonant cavity at temperatures as low as 70 mK have been measured, the sensitivity being below the SQL limit. A number of improvements in the detection efficiency and sensitivity have been planned and will be reported. Applications of the detector to fundamental physics are also discussed shortly. [ABSTRACT FROM AUTHOR]

Obtaining somatic cells from preserved organs or tissues is useful for the conservation and regeneration of genetic resources by nuclear transfer (NT). Bovine cells for NT have been obtained from cooled carcasses stored at 0C for several days (Arat et al. 2005 Reprod. Fert. Dev. 17, 164 abst) and from fetal skin tissue cryopreserved with DMSO (Fahrudin et al. 2001 J. Vet. Med. Sci. 63, 1151–1154). However, frozen storage of organs or tissues without cryoprotectants was considered to be quite inappropriate for obtaining viable cells. We report here that viable donor cells for NT were obtained from bovine testicles after frozen storage without cryoprotectants. In the first experiment, we investigated whether viable cells can be recovered from frozen testicles castrated from Japanese Black bulls. The testicles were frozen at -80C in a freezer for several days; then some were stored in liquid nitrogen for 10 months without cryoprotectants. Before thawing, the testicles were divided into 3 pieces, caput epididymis, cauda epididymis, and testis. Each piece was then put in saline at 42C for quick thawing. Thawed tissues were minced into 5-mm pieces and incubated at 39C for 2 h in DMEM containing 0.1% collagenase and 0.2% dispase. After filtration through a 250-m nylon mesh filter, the filtrates were centrifuged at 250 4g for 5 min. Then precipitates were resuspended with MF-start primary culture medium (TM Cell Research Inc., Fukui, Japan) and incubated at 38.5C under the atmosphere of 5% CO2 in air with high humidity. After 5 days of incubation, the medium was replaced and nonadherent debris was discarded. Viable cells were obtained from the caput epididymis. These cells actively proliferated and expanded. In the next experiment, to determine whether these cells can be used for NT, the cells were electrically fused with enucleated bovine oocytes. Bovine fibroblasts taken from unfrozen ear tissue were used as controls. The NT embryos were activated by Ca-ionophore treatment, followed by treatment with cycloheximide for 6 h, and then cultured in mSOF for 168 h. NT embryos reconstructed from testicle cells did not significantly differ from NT embryos made with control cells with regard to blastocyst rates (22.1% and 20.2%), cell number of blastocysts [130 43 and 121 43 (mean SD)], and ICM ratio (21.1% and 22.6%), respectively (ANOVA). These results suggest that somatic cells derived from bovine frozen testicles can be used for nuclear transfer. Further studies are needed to examine whether viable cells can be obtained from other frozen organs or tissues.This study was partially supported by a grant from the Wakayama Prefecture Collaboration of Regional Entities for the Advancement of Technological Excellence, JST. [ABSTRACT FROM AUTHOR]

Although cloning by somatic cell nuclear transfer (SCNT) has been achieved in various mammalian species, its efficiency has been very low (Han et al. 2003 Theriogenology 59, 33–44). Successful cloning requires conversion from differentiated donor nuclei to embryonic nuclei after transfer of the somatic nuclei into enucleated oocytes. Reprogramming of the transferred somatic nuclei must be completed by the time when normal activation of the embryonic genome occurs (Solter 2000 Nat. Rev. Genet. 1, 199–207). Recently, both full-term development and pre-implantation development of mouse SCNT embryos were significantly enhanced by treatment with trichostatin A (TSA), an inhibitor of histone deacetylase (Kishigami et al. 2006 Biochem. Biophys. Res. Commun. 340, 183–189; Rybouchkin et al. 2006 Biol. Reprod. 74, 1083–1089). The objective of this study was to investigate the effects of TSA on the development of bovine SCNT embryos. Bovine fibroblasts were cultured under serum starvation (0.4% FCS) for 7 days and then used as donor cells. The cells were electro-fused with bovine enucleated matured oocytes, and activated with a calcium ionophore and cycloheximide. They were subsequently cultured in mSOF medium until 168 h post-activation (hpa). The NT embryos were exposed to 0 (control), 5, 50, and 500 nM TSA from the start of activation to 48 hpa. Experiments were repeated 3 times, and the data were analyzed with Fisher''s PLSD test following ANOVA. The cleavage rates were the same among the groups (60 to 80%; P >0.05). However, the blastocyst rate of NT embryos treated with 50 nM TSA was higher than that of control embryos (40% vs. 19%, respectively; P < 0.05). On the other hand, the blastocyst rate was lower with 500 nM TSA than with 5 or 50 nM TSA (7% vs. 33% or 40%; P < 0.05). These data suggest that proper TSA treatment after somatic cloning improves the rate of development of bovine cloned embryos to the blastocyst stage. Further research is needed to examine whether NT embryos derived from different cell lines or types have similar susceptibility to TSA. [ABSTRACT FROM AUTHOR]