174 research outputs found

    Hierarchical Cluster and Region of Interest Analyses Based on Mass Spectrometry Imaging of Human Brain Tumours

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    Imaging mass spectrometry (IMS) has been rarely used to examine specimens of human brain tumours. In the current study, high quality brain tumour samples were selected by tissue observation. Further, IMS analysis was combined with a new hierarchical cluster analysis (IMS-HCA) and region of interest analysis (IMS-ROI). IMS-HCA was successful in creating groups consisting of similar signal distribution images of glial fibrillary acidic protein (GFAP) and related multiple proteins in primary brain tumours. This clustering data suggested the relation of GFAP and these identified proteins in the brain tumorigenesis. Also, high levels of histone proteins, haemoglobin subunit α, tubulins, and GFAP were identified in a metastatic brain tumour using IMS-ROI. Our results show that IMS-HCA and IMS-ROI are promising techniques for identifying biomarkers using brain tumour samples

    Experimental Investigation of the Cs Behavior in the Cesiated H- Ion Source During High Power Long Beam Operation

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    The behavior of the Cesium (Cs) in the Cs-seeded negative ion sources has been investigated experimentally under the beam accelerations of up to 0.5 MeV. The pulse length was extended to 100 s to catch the precise variations of the Cs D2 emission, discharge power, negative ion current and temperatures in the ion source. The variations of the negative ions were estimated by the beam current and the heat loads in the accelerator. This experiment shows that the buildup of temperature in the chamber walls lead to the evaporation of deposited Cs to enter the plasma region and influence the H- ion production. The H- ion beams were sustained stably by reducing the temperature rise of the chamber wall below 50 ℃. A stable long pulse beam could be achieved through the temperature control of the surfaces inside the source chamber walls

    RAW 264.7細胞におけるLPSで誘導される誘導型NO合成酵素の発現に対するCaffeic Acid Undecyl Esterの阻害について

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    We synthesized caffeic acid undecyl ester (CAUE),and found that it exhibited strong inhibitory effect of lipopolysaccharide (LPS) -induced nitric oxide (NO) production in murine macrophage-like RAW 264.7 cells.We examined the effect of CAUE on the expression inducible nitric oxide synthase (iNOS) in LPS-stimulated RAW 264.7 cells.Western blot analysis performed with specific anti-iNOS antibody showed that a decrease in NO was accompanied by a decrease in the level of iNOS protein with dose-dependent manner (CAUE:0.1~1.0μM).To clarify the mechanistic basis for CAUE\u27s ability to inhibit the induction of iNOS,we examined the effect of CAUE on nuclear factor (NF)-κB,Inhibitor-κB (IκB) degradation and phosphorylation of extracellular-signaling regulated Kinases,ERK 1/2.CAUE potently suppressed the transcriptional activity of NF-κB,IκB degradation and activation of ERK.Since NF-κB was activated by following IκBα degradation,the recovery of IκBα protein indicating that CAUE inhibited the activation of degradation following NF-κB.These finding suggest that CAUE has the inhibitory effect on LPS-induced NO production and expression of iNOS in macrophage by the inhibition of IκB degradation and NF-κB activation,which may be mediated through blockage in the phospholylation ERK

    The downstream atpE cistron is efficiently translated via its own cis-element in partially overlapping atpB–atpE dicistronic mRNAs in chloroplasts

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    The chloroplast atpB and atpE genes encode subunits β and ε of the ATP synthase, respectively. They are co-transcribed as dicistronic mRNAs in flowering plants. An unusual feature is an overlap (AUGA) of the atpB stop codon (UGA) with the atpE start codon (AUG). Hence, atpE translation has been believed to depend on atpB translation (i.e. translational coupling). Using an in vitro translation system from tobacco chloroplasts, we showed that both atpB and atpE cistrons are translated from the tobacco dicistronic mRNA, and that the efficiency of atpB translation is higher than that of atpE translation. When the atpB 5′-UTR was replaced with lower efficiency 5′-UTRs, atpE translation was higher than atpB translation. Removal of the entire atpB 5′-UTR arrested atpB translation but atpE translation still proceeded. Introduction of a premature stop codon in the atpB cistron did not abolish atpE translation. These results indicate that atpE translation is independent of atpB translation. Mutation analysis showed that the atpE cistron possesses its own cis-element(s) for translation, located ~25 nt upstream from the start codon