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Fibrosis is a prominent pathological feature of skeletal muscle in Duchenne muscular dystrophy (DMD). The commonly used disease mouse model

At the Kansai Photon Science Institute of the Japan Atomic Energy Agency, we have developed a Compton backscattered X-ray source in the energy region of a few hundred keV. The X-ray source consists of a 150-MeV electron beam, with a pulse duration of 10 ps (rms), accelerated by a Microtron accelerator and an Nd:YAG laser, with a pulse duration of 10 ns (FWHM). In the first trial experiment, the X-ray flux is estimated to be (2.2±1.0)×10 2 photons/pulse. For the actual application of an X-ray source, it is important to increase the generated X-ray flux as much as possible. Thus, for the purpose of increasing the X-ray flux, we have developed the pulse compression system for the Nd:YAG laser via stimulated Brillouin scattering (SBS). The SBS pulse compression has the great advantages of a high conversion efficiency and a simple structure. In this article, we review the present status of the Compton backscattered X-ray source and describe the SBS pulse compression system.

Synchrotron radiation-induced total reflection X-ray fluorescence (SR-TXRF) analysis is a high sensitive analytical technique that offers limits of detection in the femtogram range for most elements. Besides the analytical aspect, SR-TXRF is mainly used in combination with angle-dependent measurements and/or X-ray absorption near-edge structure (XANES) spectroscopy to gain additional information about the investigated sample. In this article, we briefly discuss the fundamentals of SR-TXRF and follow with several examples of recent research applying the above-mentioned combination of techniques to analytical problems arising from industrial applications and environmental research.

The studies undertaken by the 131I Working Group, part of the International Atomic Energy Agency's EMRAS (Environmental Modelling for Radiation Safety) programme, were focused primarily on evaluating the predictive capability of environmental models. Particular emphasis was placed on applying models to evaluate the effectiveness of countermeasures. © 2008 IAEA.

Using a cluster jet containing Ar clusters, collimated relativistic electrons up to 58 MeV with an electron charge of 2.1 nC were generated by a laser–cluster interaction. The resulting spectrum does not fit a Maxwellian distribution, but is well described by a two-temperature Maxwellian. Two-dimensional particle-in-cell simulations demonstrate an important role of clusters that the higher energy electrons are injected by the laser pulse interaction with the clusters and then they gain their energy during the direct acceleration by the laser pulse, while the lower energy electrons are accelerated by the wakefield being injected during the plasma wave breaking.

Nutrient-induced thermogenesis (NIT) induced by parenteral infusion of amino acid (AA) mixtures of different composition and of the same AA mixtures given via different routes (parenteral or intraportal infusion) were investigated in rats using a small animal indirect calorimeter. When 8 different AA solutions of differing composition but with the same total concentration were infused parenterally, both standard NIT (each AA is assumed to generate 3.28 kcal/g) and specific NIT (heat energy of each AA is calculated assuming that it is oxidized to carbon dioxide and water, and metabolised to urea and sulphuric acid) values of the leucine (Leu)-rich and the glycine (Gly)-rich solutions were significantly greater than those of the control solution. Removal of Leu or Gly from the respective AA solutions reversed the increase of both NIT values down to control levels. When the parenteral and portal infusion routes were used in one rat, both NIT values for parenteral infusion of the Leu-rich solution were again significantly greater than those of the control. Likewise, both NIT values for intrportal infusion of the Leu-rich solution were also significantly greater than those of the control. However, no difference in NIT values was found between parenteral and portal infusion of either solution. The result of this study indicated that Leu and Gly may be thermogenic AAs, and the thermogenic effect of Leu is not dependent upon the route of infusion.

The assay system of chondroitin sulfate iron colloid (CSFe) was established to evaluate the reticuloendothelial system (RES) function in individual rabbits. In the multi-dose study of CSFe, CSFe was repeatedly administered to each individual rabbit with increasing doses (0.6, 1.2, 2.4, 6.0 mg/kg) at set intervals. Blood samples were serially collected after injection of CSFe and the concentration of CSFe in serum was directly measured as an iron concentration by modifying the previously described assay method [1] to minimize the sample volume. The clearance rate of CSFe at each injected dose was computed by the least-squares method and the double-reciprocal plotting of the doses against the phagocytic velocities by the Lineweaver-Burk method was obtained in each rabbit. The maximum phagocytic velocity (Vmax) and the CSFe concentration producing 1 2 V max (Kp) obtained in ten rabbits were 0.129 ± 0.025 mg/kg per min and 0.417 ± 0.121 mg/kg (mean ± S.D.), respectively. The results obtained from this multi-dose study were comparable to our previous results obtained from the mean values of five groups given different doses [1]. The clearance rates of CSFe (0.6, 1.2, 6 mg/kg) decreased after the co-injection of 80 mg/kg of carbon colloid. The calculated Vmax and Kp in 29 rabbits were 0.125 mg/kg per min and 1.167 mg/kg. The Kp was apparently greater than that of the control (Vmax = 0.128 mg/kg per min, Kp = 0.421 mg/kg). Carbon colloid (80 mg/kg) was injected to six rabbits after the completion of the first multi-dose study of CSFe and then the second multi-dose study of CSFe was repeated after 24 h. No differences were found in Vmax and Kp between the two studies as were in the control group (10 rabbits) where saline was injected instead of carbon colloid. These results indicated that carbon colloid (80 mg/kg) gives a competitive and reversible inhibition on the RES. This multi-dose study of CSFe may be applicable for a bed-side analysis of the RES function in a patient.

Studies were performed to investigate regulatory pathways of loop diuretic-sensitive Na+/K+/Cl- cotransport in cultured rat glomerular mesangial cells. Angiotensin II, alpha-thrombin, and epidermal growth factor (EGF) all stimulated Na+/K+/Cl- cotransport in a concentration-dependent manner. Pertussis toxin pretreatment reduced the effects of angiotensin II and alpha-thrombin but not that of EGF. Addition of the protein kinase C inhibitor staurosporine or down-regulation of protein kinase C by prolonged incubation with phorbol 12-myristate 13-acetate partially reduced the effects of angiotensin II and alpha-thrombin and completely blunted the phorbol 12-myristate 13-acetate-induced stimulation of Na+/K+/Cl- cotransport but did not affect EGF-induced stimulation. Exposure of cells to a calcium ionophore, A23187, resulted in a concentration-dependent stimulation of Na+/K+/Cl- cotransport, which was not significantly inhibited by down-regulation of protein kinase C but was completely inhibited by the calmodulin antagonist, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7). Stimulation of the cotransport by angiotensin II or alpha-thrombin was also partially inhibited by W-7. Inhibitory effects of protein kinase C down-regulation and W-7 were additive and, when combined, produced a complete inhibition of angiotensin II-induced stimulation of Na+/K+/Cl- cotransport. In saponin-permeabilized mesangial cells, phosphorylation of a synthetic decapeptide substrate for Ca2+/calmodulin-dependent kinase II, Pro-Leu-Ser-Arg-Thr-Leu-Ser-Val-Ser-Ser-NH3, was demonstrated. Maximal activation of the decapeptide substrate phosphorylation required the presence of Ca2+ and calmodulin and was dependent on Ca2+ concentration. These findings indicate that stimulation of Na+/K+/Cl- cotransport by angiotensin II and alpha-thrombin is mediated by protein kinase C and Ca2+/calmodulin-dependent kinases whereas the action of EGF is mediated by other pathways.

Rationale Bronchiolitis in infancy, especially caused by Respiratory Syncytial Virus (RSV) infection, is thought to increase the risks for allergic sensitization and recurrent wheezing later in life. To investigate how RSV infection elicit immune changes in the host, mRNA expression profiles in human respiratory epithelial cells after inoculation with RSV were analyzed comprehensively. Methods Human A549 cells were inoculated with RSV (long strain) or UV-treated RSV. Total RNA was extracted from the cells at different time points, and mRNA expression profiles were assessed by an oligonucleotide probe-array system (GeneChip, Affymetrix). Results After 24 hours of culture, expression of approximately 219 out of 18,000 genes were judged increased in RSV infected cells when compared with that in cells cultured with UV-treated RSV (>2-fold by normalized data). After hierarchical clustering analysis, several gene clusters were identified. Those included type I IFN-inducible genes (Mx1, IFIT1, OAS2), pro-inflammatory cytokine genes (IL-6, TNF-α, IL-1β) and chemokines genes (IL-8, RANTES, MCP-3). However, mRNA levels for Th2 cell-attracting chemokines (TARC, MDC, or I-309) were not changed. Conclusions Out results suggest that RSV infection induces host immune responses such as inflammatory reactions through production of immunomodulatory mediators from respiratory epithelial cells.

Rationale Oligodeoxynucleotides containing unmethylated CpG motifs (CpG ODN) are known to elicit Th1 immune responses via TLR9 and are currently under investigation in patients with allergic diseases. However, the mechanisms involved are not fully understood. Methods To assess the effect of CpG ODN on the up-regulation of Th1-chemoattractant CXCR3 chemokines in human B cells, RPMI 8226 human B cell line and human peripheral B cells were cultured in the presence or absence of two distinct classes of CpG ODN - CpG-A and CpG-B - for up to 24 hours. mRNA levels of three CXCR3 chemokines - IP-10, Mig and I-TAC - were quantified by real-time PCR. Results In RPMI 8226 cells, mRNAs and proteins for IP-10, Mig and I-TAC were strongly up-regulated by CpG-B, but not by CpG-A. Though these CXCR3 chemokines are known to be induced by type I and II IFNs, blocking mAbs against IFN-α/β receptor or IFN-γ receptor did not inhibit induction of CXCR3 chemokines by CpG-B. Up-regulation of mRNAs for these CXCR3 chemokines was blocked by two NF-κB inhibitors - PDTC and MG132 - and a p38 inhibitor, SB202190, but not by a JNK inhibitor, SP600125 or a MEK inhibitor, U0126. In human B cells, exactly the same inhibitory pattern was observed. Conclusions These results strongly suggest that CXCR3 chemokines are directly induced by CpG-B but not by CpG-A via IFN-independent, NF-κB- and p38-dependent pathways in human B lymphocytes. This implies that CXCR3 chemokines may participate in part in the induction of Th1 responses by CpG-B.

The pp mass distribution in the dp → (pp)n reaction has been measured at the deuteron momentum from 1700 to 2280 MeV/c. The results show no prominent peak which suggests the existence of dibaryon resonances in the mass range of 2000 to 2200 MeV/c2.

The precipitation of hexagonal BN on the surface of an austenitic stainless steel doped with 0.05 at.% boron and 0.58 at.% nitrogen has been studied using Auger electron spectroscopy. A model which explains the surface precipitation mechanism is proposed. In this model the phenomenon proceeds through three stages: (1) a precursor state in which nitrogen atoms segregate and migrate to the surface to a considerable content: (2) a surface reaction between the nitrogen and boron atoms coming from the bulk to form a basal plane of hBN; and (3) a consequent crystal growth at the interface. The outgassing nature of these BN-precipitated surfaces has been examined using thermal desorption spectroscopy. After air exposure, only H2O was adsorbed on those regions and its adsorption density was estimated to be approximately a few tenths of a monolayer.

A Cherenkov counter with silica aerogel of refractive index 1.06 as radiator has been constructed and tested. The Cherenkov light produced in 9 cm thick silica aerogel was detected with four 5″-photomultipliers through a 162 cm long air light guide. The photoelectron yield for a 1 GeV/c pion beam was found to be 6 and uniform over a sensitive area of 40 × 30 cm2.

The polarization parameters for the π + +p→K + +∑ + reaction have been measured at 13 laboratory momenta between 1490 and 2069 MeV/ c in the angular range of −0.1⩽ cos θ K ∗ ⩽0.7 with higher statistics than previous experiments. In general, the present results agree well with the results at the Rutherford Appleton Laboratory. It is found, however, that there exist small but systematic differences which can be attributed to certain coefficients in Legendre expansions. The physical significance of these differences is discussed.

After grinding tests of coal particles in a batch, vertically vibrating mill under such three different vibration forms as sine, deformed square and pulse, grinding by the use of the deformed square vibration was found to be most efficient if the required waveform can be obtained without great difficulties, granted that the energy requirements are greater than for ordinary sine vibration.

Studies of the bacteriological and immunological characteristics of a pathogenic strain of Bacteroides melaninogenicus showed that the strain was infective when a pure culture was injected intradermally in rabbits and guinea pigs. A remarkable slime layer or capsular structure was demonstrated which was antigenically specific. A close relationship between the presence of this capsular structure and the pathogenicity of the strain was suggested.