ABSTRACT
Rare-earth intermetallic compounds exhibit rich phenomena induced by the interplay between localized f orbitals and conduction electrons. However, since the energy scale of the crystal-electric-field splitting is only a few millielectronvolts, the nature of the mobile electrons accompanied by collective crystal-electric-field excitations has not been unveiled. Here, we examine the low-energy electronic structures of CeSb through the anomalous magnetostructural transitions below the Néel temperature, ~17 K, termed the 'devil's staircase', using laser angle-resolved photoemission, Raman and neutron scattering spectroscopies. We report another type of electron-boson coupling between mobile electrons and quadrupole crystal-electric-field excitations of the 4f orbitals, which renormalizes the Sb 5p band prominently, yielding a kink at a very low energy (~7 meV). This coupling strength is strong and exhibits anomalous step-like enhancement during the devil's staircase transition, unveiling a new type of quasiparticle, named the 'multipole polaron', comprising a mobile electron dressed with a cloud of the quadrupole crystal-electric-field polarization.
ABSTRACT
The isovalent-substituted iron pnictide compound SrFe2(As1-xPx)2 exhibits multiple evidence for nodal superconductivity via various experimental probes, such as the penetration depth, nuclear magnetic resonance and specific heat measurements. The direct identification of the nodal superconducting (SC) gap structure is challenging, partly because the presence of nodes is not protected by symmetry but instead caused by an accidental sign change of the order parameter, and also because of the three-dimensionality of the electronic structure. We have studied the SC gaps of SrFe2(As0.65P0.35)2 in three-dimensional momentum space by synchrotron and laser-based angle-resolved photoemission spectroscopy. The three hole Fermi surfaces (FSs) at the zone center have SC gaps with different magnitudes, whereas the SC gaps of the electron FSs at the zone corner are almost isotropic and kz-independent. As a possible nodal SC gap structure, we propose that the SC gap of the outer hole FS changes sign around the Z-X [(0, 0, 2π) - (π, π, 2π)] direction.
ABSTRACT
Gut microbiome development affects infant health and postnatal physiology. The gut microbe assemblages of preterm infants have been reported to be different from that of healthy term infants. However, the patterns of ecosystem development and inter-individual differences remain poorly understood. We investigated hospitalised preterm infant gut microbiota development using 16S rRNA gene amplicons and the metabolic profiles of 268 stool samples obtained from 17 intensive care and 42 term infants to elucidate the dynamics and equilibria of the developing microbiota. Infant gut microbiota were predominated by Gram-positive cocci, Enterobacteriaceae or Bifidobacteriaceae, which showed sequential transitions to Bifidobacteriaceae-dominated microbiota. In neonatal intensive care unit preterm infants (NICU preterm infants), Staphylococcaceae abundance was higher immediately after birth than in healthy term infants, and Bifidobacteriaceae colonisation tended to be delayed. No specific NICU-cared infant enterotype-like cluster was observed, suggesting that the constrained environment only affected the pace of transition, but not infant gut microbiota equilibrium. Moreover, infants with Bifidobacteriaceae-dominated microbiota showed higher acetate concentrations and lower pH, which have been associated with host health. Our data provides an in-depth understanding of gut microbiota development in NICU preterm infants and complements earlier studies. Understanding the patterns and inter-individual differences of the preterm infant gut ecosystem is the first step towards controlling the risk of diseases in premature infants by targeting intestinal microbiota.
Subject(s)
Feces/microbiology , Gastrointestinal Microbiome , Gram-Positive Cocci/classification , Intensive Care Units , Acetates/analysis , Bifidobacterium/classification , Bifidobacterium/isolation & purification , Enterobacteriaceae/classification , Enterobacteriaceae/isolation & purification , Female , Gram-Positive Cocci/isolation & purification , Hospitalization , Humans , Hydrogen-Ion Concentration , Infant, Newborn , Infant, Premature , Male , Metabolome , RNA, Ribosomal, 16S/genetics , Staphylococcaceae/classification , Staphylococcaceae/isolation & purificationABSTRACT
BACKGROUND: Neutrophil elastase plays an important role in skin inflammation induced by neutrophil infiltration. Elafin is an inducible elastase inhibitor expressed by keratinocytes, and is known to be involved in pathogenesis of neutrophilic skin disorders such as psoriasis. METHODS: Immunohistochemical studies of elafin expression in the cases of vasculitis were performed. Induction of elafin expression in cultured vascular cells and its effect on neutrophil migration were studied in vitro. RESULTS: A positive immunoreactivity was detected in polyarteritis nodosa, giant cell arteritis and Schönlein-Henoch purpura, but no immunoreactivity was found in Churg-Strauss syndrome. Elafin expression in cultured venous endothelial cells and arterial smooth muscle cells was undetectable, but induced by interleukin-1ß (IL-1ß) and IL-8. Elafin inhibited the elastin peptide-induced neutrophil chemotaxis at the concentration of 10(-8) -10(-5) mol/L. CONCLUSION: Elafin deposition induced by cytokines (IL-1ß or IL-8) will be an important regulator for the progress of leucocytoclastic vasculitis by functioning as an inhibitor for neutrophil chemotaxis as well as for vascular elastin degradation.
Subject(s)
Elafin/metabolism , Neutrophils/pathology , Skin/blood supply , Tunica Intima/metabolism , Vasculitis/metabolism , Adolescent , Adult , Aged , Aged, 80 and over , Cells, Cultured , Chemotaxis, Leukocyte , Cytokines/physiology , Female , Humans , Male , Middle Aged , Young AdultABSTRACT
The objective of the study was to investigate whether an infant formula supplemented with galacto-oligosaccharides (GOS; OM55N) was able to stimulate the growth of indigenous bifidobacteria and to establish microbiota similar to that of breastfed infants. A randomised, double-blind, placebo-controlled trial was performed using 35 healthy term infants (31-54 days of age; 42±6 days) to determine whether infant formula with 0.3 g/dl GOS (OM55N) stimulated the growth of bifidobacteria in the infants' guts. At the trial onset and 2 weeks after, the infants' faecal samples were examined for microbiota composition (bacterial abundance and α-diversity) and faecal characteristics. Among the 35 infants, 5 were withdrawn and 8 were excluded from the final evaluation before breaking the blinding since the indigenous bifidobacteria were not detected at the trial onset. After 2 weeks, the abundance of Bifidobacteriaceae was significantly increased in the GOS feeding group compared to the control (+11.6±24.1% vs -3.9±13.0%; P=0.043). The Shannon index, which accounts for both abundance and evenness of the present species, was significantly decreased with GOS supplementation (-0.1±0.4 vs +0.4±0.4; P=0.014). Faecal characteristics such as pH and organic acids were similar in both groups, with no statistical differences. No adverse side effects related to the formula consumption were reported. Although the concentration of GOS was relatively low, the infant formula with GOS increased the abundance of bifidobacteria and resulted in a reduced α-diversity of the microbiota.
Subject(s)
Bifidobacterium/growth & development , Dietary Supplements , Infant Formula/chemistry , Microbiota , Oligosaccharides/pharmacology , Bifidobacterium/genetics , Double-Blind Method , Female , Galactose/administration & dosage , Galactose/pharmacology , Humans , Infant , Male , Microbiota/genetics , Oligosaccharides/administration & dosage , RNA, Bacterial , RNA, Ribosomal, 16SABSTRACT
Angiosarcoma is a rare and aggressive type of sarcoma, and primary angiosarcoma of the ovary is extremely rare. We report the case of a 29-year-old woman who was diagnosed with ovarian angiosarcoma and possible bone metastases. We treated this patient with a gemcitabine-based regimen as postoperative adjuvant chemotherapy, after which she achieved at least 7 years of progression-free survival, an extremely long duration given the aggressive features of this tumour. We retrospectively performed immunohistochemical analyses and fluorescence in situ hybridization to make a pathology diagnosis and to investigate the tumour features. MYC amplification and c-Myc protein overexpression were positively detected. It might be possible to correlate the effectiveness of the gemcitabine-based chemotherapeutic regimen with MYC gene amplification and c-Myc protein overexpression.
ABSTRACT
To identify oncogenes in leukemias, we performed large-scale resequencing of the leukemia genome using DNA sequence arrays that determine approximately 9 Mbp of sequence corresponding to the exons or exon-intron boundaries of 5648 protein-coding genes. Hybridization of genomic DNA from CD34-positive blasts of acute myeloid leukemia (n=19) or myeloproliferative disorder (n=1) with the arrays identified 9148 nonsynonymous nucleotide changes. Subsequent analysis showed that most of these changes were also present in the genomic DNA of the paired controls, with 11 somatic changes identified only in the leukemic blasts. One of these latter changes results in a Met-to-Ile substitution at amino-acid position 511 of Janus kinase 3 (JAK3), and the JAK3(M511I) protein exhibited transforming potential both in vitro and in vivo. Further screening for JAK3 mutations showed novel and known transforming changes in a total of 9 out of 286 cases of leukemia. Our experiments also showed a somatic change responsible for an Arg-to-His substitution at amino-acid position 882 of DNA methyltransferase 3A, which resulted in a loss of DNA methylation activity of >50%. Our data have thus shown a unique profile of gene mutations in human leukemia.
Subject(s)
Genomics/methods , Leukemia/genetics , Oligonucleotide Array Sequence Analysis/methods , Sequence Analysis, DNA/methods , Amino Acid Sequence , Animals , Base Sequence , Cell Transformation, Neoplastic , DNA (Cytosine-5-)-Methyltransferases/chemistry , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA Methyltransferase 3A , Genome, Human/genetics , Humans , Janus Kinase 3/genetics , Leukemia/pathology , Mice , Molecular Sequence Data , MutationABSTRACT
Muon spin relaxation measurements in iron-oxypnictide systems have revealed: (1) commensurate long-range order in undoped LaFeAsO; (2) a Bessel function line shape in LaFeAs(O0.97F0.03) which indicates possible incommensurate or stripe magnetism; (3) anomalous weak magnetism existing in superconducting LaFePO, CeFeAs(O0.084F0.16), and NdFeAs(O0.88F0.12) but absent in superconducting LaFeAs(O0.92F0.08); and (4) scaling of the superfluid density with T_{c} in the Ce-, La-, and Nd-FeAs superconductors following a nearly linear relationship found in cuprates.
ABSTRACT
The Japanese rose bitterling (Rhodeus ocellatus kurumeus) is facing imminent extinction because of hybridization and competition from an invasive alien subspecies (Rhodeus ocellatus ocellatus). Eleven new microsatellite markers for the two subspecies were developed using dinucleotide repeat specific polymerase chain reaction. The number of alleles per locus and the heterozygosity in R. o. kurumeus were lower than those in R. o. ocellatus. Most of these microsatellite markers were successfully cross-amplified in three Acheilognathinae species.
ABSTRACT
Angle-resolved photoemission spectroscopy with low-energy tunable photons along the nodal direction of oxygen isotope substituted Bi(2)Sr(2)CaCu(2)O(8+delta) reveals a distinct oxygen isotope shift near the electron-boson coupling "kink" in the electronic dispersion. The magnitude (a few meV) and direction of the kink shift are as expected due to the measured isotopic shift of phonon frequency, and are also in agreement with theoretical expectations. This demonstrates the participation of the phonons as dominant players, as well as pinpointing the most relevant of the phonon branches.
ABSTRACT
Reactive oxygen species play an important role in the pathogenesis of acute lung injury and pulmonary fibrosis. The present authors hypothesise that edaravone, a free-radical scavenger, is able to attenuate bleomycin (BLM)-induced lung injury in mice by decreasing oxidative stress. Lung injury was induced in female ICR mice by intratracheal instillation of 5 mg x kg(-1) of BLM. Edaravone (300 mg x kg(-1)) was administered by intraperitoneal administration 1 h before BLM challenge. Edaravone significantly improved the survival rate of mice treated with BLM from 25 to 90%, reduced the number of total cells and neutrophils in bronchoalveolar lavage fluid (BALF) on day 7, and attenuated the concentrations of lipid hydroperoxide in BALF and serum on day 2. The fibrotic change in the lung on day 28 was ameliorated by edaravone, as evaluated by histological examination and measurement of hydroxyproline contents. In addition, edaravone significantly increased the prostaglandin E(2) concentration in BALF on day 2. In summary, edaravone was shown to inhibit lung injury and fibrosis via the repression of lipid hydroperoxide production and the elevation of prostaglandin E(2) production in the present experimental murine system.
Subject(s)
Antipyrine/analogs & derivatives , Bleomycin/pharmacology , Free Radical Scavengers/pharmacology , Lung Injury/chemically induced , Lung Injury/drug therapy , Lung/drug effects , Animals , Antipyrine/pharmacology , Bronchoalveolar Lavage Fluid , Dinoprostone/metabolism , Edaravone , Female , Lipids/chemistry , Mice , Mice, Inbred ICR , Oxidative Stress , Pulmonary Fibrosis/drug therapy , Reactive Oxygen SpeciesABSTRACT
Plasma treatment of polymer surfaces can modify the nanoscale roughness, wettability, and oxygen surface functionalities. However, how these modifications regulate cell behavior is not well understood. The objective of this investigation was to examine adhesion, spreading, and cytoskeleton of vascular endothelial cells seeded on low-density polyethylene surfaces modified by Ar plasma. In the absence of serum, adhesion and spreading of the cells and actin filament assembly were enhanced by high-energy Ar plasma-induced hydrophilicity and formation of C-O groups at the surface. Although serum increased cell adhesion and spreading on untreated surfaces for a relatively short period, this behavior was not stable for a long time. In contrast to the untreated polymer surfaces, serum suppressed cell adhesion and spreading on the plasma-treated surfaces. The preadsorption of albumin from the bovine serum on the polymer surfaces inhibited cell adhesion and spreading. Results demonstrate the differential effects of Ar plasma-induced surface modifications on endothelial cell behavior and provide insight into complex interactions among polymer surfaces, adsorbed proteins, and cells. The findings of this study have significant implications in surface engineering for vascular repair.
Subject(s)
Argon , Cytoskeleton/metabolism , Endothelial Cells/physiology , Polyethylene , Animals , Biocompatible Materials , Cattle , Cell Adhesion/physiology , Nitric Oxide Synthase Type IIIABSTRACT
AIMS: To isolate a strain overproducing riboflavin and to improve riboflavin production for practical use in a biorefinery technology. METHODS AND RESULTS: Ashbya gossypii spores were mutagenized by exposure to UV light and mutant ZP4 strain, producing riboflavin threefold the riboflavin that of the wild-type strain, was isolated by the first and second screenings. Proteomic analysis of ZP4 strain showed the expression patterns of eight types of genes related to riboflavin biosynthesis different from those of the wild-type strain and those enzyme activities were investigated. When activated bleaching earth (ABE) containing 75 g l(-1) rapeseed oil was added in the culture of the ZP4 strain with oxygen-enriched air supplied, riboflavin concentration increased to 8.7 g l(-1) at 5 days of culture. Riboflavin production yield was 0.17 g g(-1) of consumed oil, which was eightfold higher than that of the wild-type strain. CONCLUSIONS: The results show that the mutant ZP4 strain shows potential for improving riboflavin production for practical utilization using vegetable oil as the sole carbon source. SIGNIFICANCE AND IMPACT OF STUDY: Our results indicate that the mutant ZP4 strain shows potential for producing riboflavin from vegetable oil, and therefore will be contributed to biorefinery technology.
Subject(s)
Industrial Microbiology/methods , Riboflavin/biosynthesis , Saccharomycetales/isolation & purification , Culture Media , Fermentation , Fungal Proteins/analysis , Gene Expression Regulation, Fungal/genetics , Genes, Fungal/genetics , Genetic Engineering/methods , Mutation , Oxidoreductases/metabolism , Plant Oils/metabolism , Proteome/analysis , Saccharomycetales/genetics , Saccharomycetales/metabolism , Spores, Fungal/isolation & purification , Succinates/metabolismABSTRACT
We have examined the spin structure of the proton in the region of the nucleon resonances (1.085 GeV
ABSTRACT
The anisotropic field dependence of the Sommerfeld coefficient gamma has been measured down to B-->0 by combining specific heat and Hall probe magnetization measurements in MgB2 single crystals. We find that gamma(B,theta) is the sum of two contributions arising from the sigma and pi band, respectively. We show that gammasigma(B,theta)=B/Bc2(theta) where Bc2(theta)=Bc2ab/sqrt[sin2theta+Gamma2cos2theta] with Gamma approximately 5.4 (theta being the angle between the applied field and the c axis) and gammapi(B,theta)=gammapi(B)=B/Bpi(B). The "critical field" of the pi band Bpi is fully isotropic but field dependent increasing from approximately 0.25 T for B< or =0.1 T up to 3 T approximately Bc2c for B-->3 T. Because of the coupling of the two bands, superconductivity survives in the pi band up to 3 T but is totally destroyed above for any orientation of the field.
ABSTRACT
We successfully detected dengue virus (DENV) genome in urine and saliva but not in plasma samples from a Japanese dengue fever patient. The results of the present study suggest that detection of DENV genome in urine and saliva can be an effective diagnostic method, particularly for children with viral hemorrhage.