Hedgehog Spin-Vortex Crystal Antiferromagnetic Quantum Criticality in CaK(Fe_{1-x}Ni_{x})_{4}As_{4} Revealed by NMR.

Two ordering states, antiferromagnetism and nematicity, have been observed in most iron-based superconductors (SCs). In contrast to those SCs, the newly discovered SC CaK(Fe_{1-x}Ni_{x})_{4}As_{4} exhibits an antiferromagnetic (AFM) state, called hedgehog spin-vortex crystal (SVC) structure, without nematic order, providing the opportunity for the investigation into the relationship between spin fluctuations and SC without any effects of nematic fluctuations. Our ^{75}As nuclear magnetic resonance studies on CaK(Fe_{1-x}Ni_{x})_{4}As_{4} (0≤x≤0.049) revealed that CaKFe_{4}As_{4} is located close to a hidden hedgehog SVC AFM quantum-critical point (QCP). The magnetic QCP without nematicity in CaK(Fe_{1-x}Ni_{x})_{4}As_{4} highlights the close connection of spin fluctuations and superconductivity in iron-based SCs. The advantage of stoichiometric composition also makes CaKFe_{4}As_{4} an ideal platform for further detailed investigation of the relationship between magnetic QCP and superconductivity in iron-based SCs without disorder effects.

Spin Liquid State in the 3D Frustrated Antiferromagnet PbCuTe_{2}O_{6}: NMR and Muon Spin Relaxation Studies.

PbCuTe_{2}O_{6} is a rare example of a spin liquid candidate featuring a three-dimensional magnetic lattice. Strong geometric frustration arises from the dominant antiferromagnetic interaction that generates a hyperkagome network of Cu^{2+} ions although additional interactions enhance the magnetic lattice connectivity. Through a combination of magnetization measurements and local probe investigations by NMR and muon spin relaxation down to 20 mK, we provide robust evidence for the absence of magnetic freezing in the ground state. The local spin susceptibility probed by the NMR shift hardly deviates from the macroscopic one down to 1 K pointing to a homogeneous magnetic system with a low defect concentration. The saturation of the NMR shift and the sublinear power law temperature (T) evolution of the 1/T_{1} NMR relaxation rate at low T point to a nonsinglet ground state favoring a gapless fermionic description of the magnetic excitations. Below 1 K a pronounced slowing down of the spin dynamics is witnessed, which may signal a reconstruction of spinon Fermi surface. Nonetheless, the compound remains in a fluctuating spin liquid state down to the lowest temperature of the present investigation.

Competing Magnetic Fluctuations in Iron Pnictide Superconductors: Role of Ferromagnetic Spin Correlations Revealed by NMR.

In the iron pnictide superconductors, theoretical calculations have consistently shown enhancements of the static magnetic susceptibility at both the stripe-type antiferromagnetic and in-plane ferromagnetic (FM) wave vectors. However, the possible existence of FM fluctuations has not yet been examined from a microscopic point of view. Here, using ^{75}As NMR data, we provide clear evidence for the existence of FM spin correlations in both the hole- and electron-doped BaFe_{2}As_{2} families of iron-pnictide superconductors. These FM fluctuations appear to compete with superconductivity and are thus a crucial ingredient to understanding the variability of T_{c} and the shape of the superconducting dome in these and other iron-pnictide families.

RISING beamline (BL28XU) for rechargeable battery analysis.

The newly installed BL28XU beamline at SPring-8 is dedicated to in situ structural and electronic analysis of rechargeable batteries. It supports the time range (1 ms to 100 s) and spatial range (1 µm to 1 mm) needed for battery analysis. Electrochemical apparatus for battery charging and discharging are available in experimental hutches and in a preparation room. Battery analysis can be carried out efficiently and effectively using X-ray diffraction, X-ray absorption fine-structure analysis and hard X-ray photoelectron spectroscopy. Here, the design and performance of the beamline are described, and preliminary results are presented.

Magnetic properties and hyperfine interactions in Cr8, Cr7Cd, and Cr7Ni molecular rings from ¹9F-NMR.

A detailed experimental investigation of the (19)F nuclear magnetic resonance is made on single crystals of the homometallic Cr8 antiferromagnetic molecular ring and heterometallic Cr7Cd and Cr7Ni rings in the low temperature ground state. Since the F(-) ion is located midway between neighboring magnetic metal ions in the ring, the (19)F-NMR spectra yield information about the local electronic spin density and (19)F hyperfine interactions. In Cr8, where the ground state is a singlet with total spin S(T) = 0, the (19)F-NMR spectra at 1.7 K and low external magnetic field display a single narrow line, while when the magnetic field is increased towards the first level crossing field, satellite lines appear in the (19)F-NMR spectrum, indicating a progressive increase in the Boltzmann population of the first excited state S(T) = 1. In the heterometallic rings, Cr7Cd and Cr7Ni, whose ground state is magnetic with S(T) = 3/2 and S(T) = 1/2, respectively, the (19)F-NMR spectrum has a complicated structure which depends on the strength and orientation of the magnetic field, due to both isotropic and anisotropic transferred hyperfine interactions and classical dipolar interactions. From the (19)F-NMR spectra in single crystals we estimated the transferred hyperfine constants for both the F(-)-Ni(2+) and the F(-)-Cd(2+) bonds. The values of the hyperfine constants compare well to the ones known for F(-)-Ni(2+) in KNiF3 and NiF2 and for F(-)-Cr(3+) in K2NaCrF6. The results are discussed in terms of hybridization of the 2s, 2p orbitals of the F(-) ion and the d orbitals of the magnetic ion. Finally, we discuss the implications of our results for the electron-spin decoherence.

Comprehensive validation of early diagnostic algorithms for myocardial infarction in the emergency department.

OBJECTIVE: To comprehensively evaluate diagnostic algorithms for myocardial infarction using a high-sensitivity cardiac troponin I (hs-cTnI) assay. PATIENTS AND METHODS: We prospectively enrolled patients with suspected myocardial infarction without ST-segment elevation from nine emergency departments in Japan. The diagnostic algorithms evaluated: (i) based on hs-cTnI alone, such as the European Society of Cardiology (ESC) 0/1-h or 0/2-h and High-STEACS pathways; or (ii) used medical history and physical findings, such as the ADAPT, EDACS, HEART, and GRACE pathways. We evaluated the negative predictive value (NPV), sensitivity as safety measures, and proportion of patients classified as low or high-risk as an efficiency measure for a primary outcome of type 1 myocardial infarction or cardiac death within 30 days. RESULTS: We included 437 patients, and the hs-cTnI was collected at 0 and 1 hours in 407 patients and at 0 and 2 hours in 394. The primary outcome occurred in 8.1% (33/407) and 6.9% (27/394) of patients, respectively. All the algorithms classified low-risk patients without missing those with the primary outcome, except for the GRACE pathway. The hs-cTnI-based algorithms classified more patients as low-risk: the ESC 0/1-h 45.7%; the ESC 0/2-h 50.5%; the High-STEACS pathway 68.5%, than those using history and physical findings (15-30%). The High-STEACS pathway ruled out more patients (20.5%) by hs-cTnI measurement at 0 hours than the ESC 0/1-h and 0/2-h algorithms (7.4%). CONCLUSIONS: The hs-cTnI algorithms, especially the High-STEACS pathway, had excellent safety performance for the early diagnosis of myocardial infarction and offered the greatest improvement in efficiency.

Coexistence of half-metallic itinerant ferromagnetism with local-moment antiferromagnetism in Ba0.60K0.40Mn2As2.

Magnetization, nuclear magnetic resonance, high-resolution x-ray diffraction, and magnetic field-dependent neutron diffraction measurements reveal a novel magnetic ground state of Ba0.60K0.40Mn2As2 in which itinerant ferromagnetism (FM) below a Curie temperature TC≈100 K arising from the doped conduction holes coexists with collinear antiferromagnetism (AFM) of the Mn local moments that order below a Néel temperature TN=480 K. The FM ordered moments are aligned in the tetragonal ab plane and are orthogonal to the AFM ordered Mn moments that are aligned along the c axis. The magnitude and nature of the low-T FM ordered moment correspond to complete polarization of the doped-hole spins (half-metallic itinerant FM) as deduced from magnetization and ab-plane electrical resistivity measurements.

AXIN1 mutations in hepatocellular carcinomas, and growth suppression in cancer cells by virus-mediated transfer of AXIN1.

The Wnt signaling pathway is essential for development and organogenesis. Wnt signaling stabilizes beta-catenin, which accumulates in the cytoplasm, binds to 1-cell factor (TCF; also known as lymphocyte enhancer-binding factor, LEF) and then upregulates downstream genes. Mutations in CTNNB1 (encoding beta-catenin) or APC (adenomatous polyposis coli) have been reported in human neoplasms including colon cancers and hepatocellular carcinomas (HCCs). Because HCC5 tend to show accumulation of beta-catenin more often than mutations in CTNNB1, we looked for mutations in AXIN1, encoding a key factor for Wnt signaling, in 6 HCC cell lines and 100 primary HCC5. Among the 4 cell lines and 87 HCC5 in which we did not detect CTNNB1 mutations, we identified AXIN1 mutations in 3 cell lines and 6 mutations in 5 of the primary HCCs. In cell lines containing mutations in either gene, we observed increased DNA binding of TCF associated with beta-catenin in nuclei. Adenovirus mediated gene transfer of wild-type AXINI induced apoptosis in hepatocellular and colorectal cancer cells that had accumulated beta-catenin as a consequence of either APC, CTNNB1 or AXIN1 mutation, suggesting that axin may be an effective therapeutic molecule for suppressing growth of hepatocellular and colorectal cancers.

The role of serum adiponectin levels in women with polycystic ovarian syndrome.

PURPOSE OF INVESTIGATION: The aim of this study was to measure serum adiponectin concentrations in women with polycystic ovarian syndrome (PCOS) and to assess possible correlations between adiponectin and the hormonal or metabolic parameters of this syndrome. MATERIALS AND METHODS: Serum adiponectin levels were evaluated in 20 women with PCOS and 22 women without PCOS whose age and body mass index (BMI) matched the patients. The levels of fasting blood glucose, fasting insulin, gonadotropin, and sex steroid hormones were evaluated in both groups. The homeostasis model assessment (HOMA) score was also calculated. The serum adiponectin levels were assayed by enzyme-linked immunoabsorbent assay (ELISA). RESULTS: Serum adiponectin levels were significantly lower in obese women than in normal-weight women, and they were also significantly lower in PCOS patients with HOMA scores greater than 1.7 compared with those with HOMA scores lower than 1.7. When the subjects were divided in two groups based on serum adiponectin levels (> 40 microg/ml, < 40 microg/ml), 65% of patients with PCOS were included in the lower adiponectin group (p < 0.05). In addition, gonadotropin levels were increased, dependent on the adiponectin levels in women with PCOS. CONCLUSION: Adiponectin is regarded as a possible link between adiposity and insulin resistance (IR). From this data, the secretions of gonadotropin are implicated in the levels of adiponectin in women with PCOS. It is suggested that adiponectin may play an important role in the pathogenesis of PCOS.

Antiferromagnetic order and its interplay with superconductivity in CaK(Fe1-xMnx)4As4.

The magnetic order for several compositions of CaK(Fe1-xMnx)4As4has been studied by nuclear magnetic resonance (NMR), Mössbauer spectroscopy, and neutron diffraction. Our observations for the Mn-doped 1144 compound are consistent with the hedgehog spin vortex crystal (hSVC) order which has previously been found for Ni-dopedCaKFe4As4. The hSVC state is characterized by the stripe-type propagation vectors(π0)and(0π)just as in the doped 122 compounds. The hSVC state preserves tetragonal symmetry at the Fe site, and only this SVC motif with simple antiferromagnetic (AFM) stacking alongcis consistent with all our observations using NMR Mössbauer spectroscopy, and neutron diffraction. We find that the hSVC state in the Mn-doped 1144 compound coexists with superconductivity, and by combining the neutron scattering and Mössbauer spectroscopy data we can infer a quantum phase transition, hidden under the superconducting dome, associated with the suppression of the AFM transition temperature (TN) to zero forx ≈ 0.01. In addition, unlike several 122 compounds and Ni-doped 1144, the ordered magnetic moment is not observed to decrease at temperatures below the superconducting transition temperature (Tc).

Regulation of interleukin-1alpha and tumor necrosis factor-alpha-induced interleukin-8 production by amnion-derived (WISH) cells.

PURPOSE OF INVESTIGATION: It has been reported that interleukin (IL)-8 is produced in the amnion and that its production is enhanced by the initiation of labor. The purpose of this study was to clarify the mechanism of IL-8 production by amnion-derived (WISH) cells. METHODS: Cells were cultured and treated with various concentrations of interleukin (IL)-1alpha, IL-1 receptor antagonist (ra), tumor necrosis factor (TNF)- alpha, C2-, C6-ceramide, mitogen-activated protein (MAP) kinase kinase (MEK) inhibitor (U0126) and pyridinyl imidazole (p38 MAP kinase inhibitor, SB203580). IL-8 in the culture medium was measured by ELISA. RESULTS: The production of IL-8 was significantly increased by IL-1alpha or TNF-alpha, and the increase of IL-8 stimulated by IL-1alpha was suppressed by IL-1 ra in a dose-dependent manner. The increase in IL-8 production by IL-1alpha or TNF-alpha was further enhanced by simultaneous addition of C2-ceramide. The increase of IL-8 stimulated by IL-1alpha or TNF-alpha was also suppressed by treatment with U0126 or SB203580. The results of this study demonstrate that the production of IL-8 induced by IL-1alpha and TNF-alpha is enhanced by C2-ceramide, and suppressed by MEK inhibitor or P38 MAP kinase inhibitor. CONCLUSION: The results suggest that ceramide-mediated accumulation and MAP kinase-mediated suppression of inflammatory events in the amnion may play an important role in the maintenance of pregnancy and initiation of labor.

Oscillating flower colour changes of Causonis japonica (Thunb.) Raf. (Vitaceae) linked to sexual phase changes.

Flower colour change may represent an 'honest signal' for pollinators, denoting flowers with good conditions for rewards and pollination. All previously reported flower colour changes are unidirectional, except for an incomplete case in one Fabaceae species. In this study, we discovered a very rare example of complete oscillating flower colour change associated with sexual phase changes in Causonis japonica (Vitaceae). More specifically, flower discs of C. japonica exhibit an orange colour in the initial male phase then soon fade into pink with desorption of the stamens. Several hours later in the daytime of the same or the following day, with stigma maturation and style elongation, the orange flower disc colour is recovered before fading into pink again. Importantly, we found that the colour change is caused by the accumulation and the degradation of carotenoids. Moreover, nectar secretion was roughly correlated with the abovementioned colour changes. This is the first example of an apparent oscillating colour change mediated by carotenoid content alteration in flowers.

Growth inhibition at the ice prismatic plane induced by a spruce budworm antifreeze protein: a molecular dynamics simulation study.

A molecular dynamics simulation was conducted to investigate the growth kinetics at the ice prismatic interface to which a spruce budworm antifreeze protein was bound. Two initial binding conformations of the protein at the interface--one energetically stable and the other energetically unstable--were examined. For both binding conformations, the growth of ice was observed around the protein. A sharp decrease in the rate of ice growth was observed around the protein that initially had the energetically stable binding conformation. Simulation results suggest that the observed decrease in the ice growth rate was attributable to melting point depression caused by the Gibbs-Thomson effect. The protein that initially had the energetically unstable binding conformation markedly relaxed so as to stably bind to the prismatic plane interface of the grown ice; thereafter, a decrease in the ice growth rate was observed as well. However, the binding conformation that the protein approached during the relaxation was different from that of the protein that initially had the energetically stable binding conformation. Thus, the simulation indicates the existence of two binding conformations for inducing a decrease in the ice growth rate. The results are possibly related to the hyperactivity of a spruce budworm antifreeze protein in real systems.

C20orf20 (MRG-binding protein) as a potential therapeutic target for colorectal cancer.

BACKGROUND: Colorectal cancer is one of the most common causes of cancer death worldwide. Using cDNA microarray containing 23 040 genes, we earlier investigated gene-expression profiles in 11 colorectal cancers for the purpose of better understanding of colorectal carcinogenesis as well as development of novel diagnostic and therapeutic strategies. MRG-binding protein (MRGBP) or C20orf20, encoding a subunit of TRRAP/TIP60-containing histone acetyltransferase complex, was up-regulated in the majority of colorectal tumours. METHODS AND RESULTS: The elevated expression of MRGBP was observed in colorectal cancer tissues by quantitative PCR as well as immunohistochemical analyses. MRGBP marginally expressed in normal vital organs. Notably, suppressed MRGBP expression by MRGBP short hairpin RNA inhibited proliferation of colorectal cancer cells. Yeast two-hybrid screening and subsequent immunoprecipitation analysis identified bromodomain containing 8 (BRD8) as an MRGBP-interacting protein. As RNA interference against BRD8 also suppressed proliferation of colorectal cancer cells, BRD8 may be an important down-stream target of MRGBP. CONCLUSION: These results suggest that MRGBP has an important function in proliferation of cancer cells through the regulation of BRD8 and that MRGBP should be a novel therapeutic target for colorectal cancer.

Downregulation of an AIM-1 kinase couples with megakaryocytic polyploidization of human hematopoietic cells.

During the late phase of megakaryopoiesis, megakaryocytes undergo polyploidization, which is characterized by DNA duplication without concomitant cell division. However, it remains unknown by which mechanisms this process occurs. AIM-1 and STK15 belong to the Aurora/increase-in-ploidy (Ipl)1 serine/threonine kinase family and play key roles in mitosis. In a human interleukin-3-dependent cell line, F-36P, the expressions of AIM-1 and STK15 mRNA were specifically observed at G2/M phase of the cell cycle during proliferation. In contrast, the expressions of AIM-1 and STK15 were continuously repressed during megakaryocytic polyploidization of human erythro/megakaryocytic cell lines (F-36P, K562, and CMK) treated with thrombopoietin, activated ras (H-ras(G12V)), or phorbol ester. Furthermore, their expressions were suppressed during thrombopoietin-induced polyploidization of normal human megakaryocytes. Activation of AIM-1 by the induced expression of AIM-1(wild-type) canceled TPA-induced polyploidization of K562 cells significantly, whereas that of STK15 did not. Moreover, suppression of AIM-1 by the induced expression of AIM-1 (K/R, dominant-negative type) led to polyploidization in 25% of K562 cells, whereas STK15(K/R) showed no effect. Also, the induced expression of AIM-1(K/R) in CMK cells provoked polyploidization up to 32N. These results suggested that downregulation of AIM-1 at M phase may be involved in abortive mitosis and polyploid formation of megakaryocytes.

Vasoactive intestinal peptide and inflammatory cytokines enhance vascular endothelial growth factor production from epidermal keratinocytes.

BACKGROUND: Overexpression of vascular endothelial growth factor (VEGF) in epidermal lesions of psoriasis is well documented; however, its underlying mechanisms are largely unknown. We have recently demonstrated that vasoactive intestinal peptide (VIP) induces the production of cytokines such as interleukin-6 and stem cell factor from keratinocytes, thereby contributing to the development of inflammatory dermatoses such as psoriasis. OBJECTIVES: In this study, we attempted to determine whether VIP could increase the production of VEGF in human keratinocytes. METHODS: We examined the expression of VEGF using reverse transcription-polymerase chain reaction, immunocytochemistry, enzyme-linked immunosorbent assay and immunoblotting in normal human epidermal keratinocytes and human epidermal keratinocyte cell line DJM-1 cultured in the absence or presence of VIP and/or inflammatory cytokines. RESULTS: We demonstrate that human keratinocytes produced VEGF in a steady state at both mRNA and protein levels. VIP significantly upregulated the production of VEGF in keratinocytes in a dose- and time-dependent manner. The VIP-mediated production of VEGF was further enhanced by inflammatory cytokines such as interferon-gamma, tumour necrosis factor-alpha and interleukin-4, with maximum enhancement being observed with the combination of VIP and interferon-gamma. CONCLUSIONS: VIP and other cytokines from nerve endings, mast cells and local inflammatory cells are capable of enhancing VEGF production from epidermal keratinocytes, which may underlie excessive angiogenesis and vasodilation in skin lesions of psoriasis.

Double seismic zone for deep earthquakes in the izu-bonin subduction zone.

A double seismic zone for deep earthquakes was found in the Izu-Bonin region. An analysis of SP-converted phases confirms that the deep seismic zone consists of two layers separated by approximately 20 kilometers. Numerical modeling of the thermal structure implies that the hypocenters are located along isotherms of 500 degrees to 550 degrees C, which is consistent with the hypothesis that deep earthquakes result from the phase transition of metastable olivine to a high-pressure phase in the subducting slab.

cdc2 gene expression at the G1 to S transition in human T lymphocytes.

The product of the cdc2 gene, designated p34cdc2, is a serine-threonine protein kinase that controls entry of eukaryotic cells into mitosis. Freshly isolated human T lymphocytes (G0 phase) were found to have very low amounts of p34cdc2 and cdc2 messenger RNA. Expression of cdc2 increased 18 to 24 hours after exposure of T cells to phytohemagglutinin, coincident with the G1 to S transition. Antisense oligodeoxynucleotides could reduce the increase in cdc2 expression and inhibited DNA synthesis, but had no effect on several early and mid-G1 events, including blastogenesis and expression of interleukin-2 receptors, transferrin receptors, c-myb, and c-myc. Induction of cdc2 required prior induction of c-myb and c-myc. These results suggest that cdc2 induction is part of an orderly sequence of events that occurs at the G1 to S transition in T cells.

Huge ameloblastic carcinoma of the mandible with metastases treated in several different ways.

Ameloblastic carcinoma is an extremely rare, aggressive, malignant tumour that is most common in the mandible. Because of its rarity there is no general approach to treatment. We present a rare case of an ameloblastic carcinoma with multiple metastases in a 63-year-old Japanese man that was treated in several different ways, including chemoradiotherapy and immunotherapy.