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21.
22.
Hidefumi Uchiyama Qing-Li Zhao Mariame Ali Hassan Gabor Andocs Nobuyuki Nojima Keigo Takeda Kenji Ishikawa Masaru Hori Takashi Kondo 《PloS one》2015,10(8)
Electron paramagnetic resonance (EPR)-spin trapping and flow cytometry were used to identify free radicals generated using argon-cold atmospheric plasma (Ar-CAP) in aqueous solutions and intracellularly in comparison with those generated by X-irradiation. Ar-CAP was generated using a high-voltage power supply unit with low-frequency excitation. The characteristics of Ar-CAP were estimated by vacuum UV absorption and emission spectra measurements. Hydroxyl (·OH) radicals and hydrogen (H) atoms in aqueous solutions were identified with the spin traps 5,5-dimethyl-1-pyrroline N-oxide (DMPO), 3,3,5,5-tetramethyl-1-pyrroline-N-oxide (M4PO), and phenyl N-t-butylnitrone (PBN). The occurrence of Ar-CAP-induced pyrolysis was evaluated using the spin trap 3,5-dibromo-4-nitrosobenzene sulfonate (DBNBS) in aqueous solutions of DNA constituents, sodium acetate, and L-alanine. Human lymphoma U937 cells were used to study intracellular oxidative stress using five fluorescent probes with different affinities to a number of reactive species. The analysis and quantification of EPR spectra revealed the formation of enormous amounts of ·OH radicals using Ar-CAP compared with that by X-irradiation. Very small amounts of H atoms were detected whereas nitric oxide was not found. The formation of ·OH radicals depended on the type of rare gas used and the yield correlated inversely with ionization energy in the order of krypton > argon = neon > helium. No pyrolysis radicals were detected in aqueous solutions exposed to Ar-CAP. Intracellularly, ·OH, H2O2, which is the recombination product of ·OH, and OCl- were the most likely formed reactive oxygen species after exposure to Ar-CAP. Intracellularly, there was no practical evidence for the formation of NO whereas very small amounts of superoxides were formed. Despite the superiority of Ar-CAP in forming ·OH radicals, the exposure to X-rays proved more lethal. The mechanism of free radical formation in aqueous solutions and an intracellular milieu is discussed. 相似文献
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24.
Hattori M Kondo T Kishi M Yamagami K 《Bioscience, biotechnology, and biochemistry》2010,74(10):2158-2159
We have reported that acetic acid (AcOH) intake suppresses body fat mass and up-regulates the genes involved in fatty acid oxidation, but it is not clear whether the suppression of body fat mass by AcOH administration is due to an increase in energy expenditure (EE). In this study, we investigated to determine whether a single oral administration of AcOH would increase EE in C57BL/6J mice treated with 1.5% AcOH. The AcOH treatment group had significantly higher oxygen consumption (VO(2)), EE, and fat oxidation (FAT) than the water treatment group. These results suggest that a single administration of AcOH increases EE, resulting in suppression of body fat mass. 相似文献
25.
Kawamoto Y Shotake T Nozawa K Kawamoto S Tomari K Kawai S Shirai K Morimitsu Y Takagi N Akaza H Fujii H Hagihara K Aizawa K Akachi S Oi T Hayaishi S 《Primates; journal of primatology》2007,48(1):27-40
We investigated the diversity and phylogeography of mitochondrial DNA (mtDNA) in Japanese macaques (Macaca fuscata), an endemic species in Japan that has the northernmost distribution of any non-human primate species. DNA samples from 135
localities representing the entire range of this species were compared. A total of 53 unique haplotypes were observed for
the 412-bp partial mtDNA control region sequence, with length variation distinguishing the two subspecies. Clustering analyses
suggested two putative major haplogroups, of which one was geographically distributed in eastern Japan and the other in western
Japan. The populations in the east showed lower mtDNA diversity than those in the west. Phylogeographical relationships of
haplotypes depicted with minimum spanning network suggested differences in population structure. Population expansion was
significant for the eastern but not the western population, suggesting establishment of the ancestral population was relatively
long ago in the west and recent in the east. Based on fossil evidence and past climate and vegetation changes, we inferred
that the postulated population expansion may have taken place after the last glacial period (after 15,000 years ago). Mitochondrial
DNA showed contrasting results in both variability and phylogenetic status of local populations to those of previous studies
using protein variations, particularly for populations in the periphery of the range, with special inference on habitat change
during the glacial period in response to cold adaptation.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
26.
Teno N Miyake T Ehara T Irie O Sakaki J Ohmori O Gunji H Matsuura N Masuya K Hitomi Y Nonomura K Horiuchi M Gohda K Iwasaki A Umemura I Tada S Kometani M Iwasaki G Cowan-Jacob SW Missbach M Lattmann R Betschart C 《Bioorganic & medicinal chemistry letters》2007,17(22):6096-6100
Pyrrolopyrimidine, a novel scaffold, allows to adjust interactions within the S3 subsite of cathepsin K. The core intermediate 10 facilitated the P3 optimization and identified highly potent and selective cathepsin K inhibitors 11-20. 相似文献
27.
Shibayama K Wachino J Arakawa Y Saidijam M Rutherford NG Henderson PJ 《Molecular microbiology》2007,64(2):396-406
gamma-Glutamyltranspeptidase (GGT) is a periplasmic enzyme of Helicobacter pylori implicated in its pathogenesis towards mammalian cells. We have cloned and expressed the H. pylori strain 26695 recombinant GGT protein in Escherichia coli and purified it to homogeneity. The purified protein exhibited hydrolysis activity with very high affinities for glutamine and glutathione shown by apparent K(m) values lower than 1 muM. H. pylori cells were unable to take up extracellular glutamine and glutathione directly. Instead, these substances were hydrolysed to glutamate by the action of GGT outside the cells. The glutamate produced was then transported by a Na(+)-dependent reaction into H. pylori cells, where it was mainly incorporated into the TCA cycle and partially utilized as a substrate for glutamine synthesis. These observations show that one of the principle physiological functions of H. pylori GGT is to enable H. pylori cells to utilize extracellular glutamine and glutathione as a source of glutamate. As glutamine and glutathione are important nutrients for maintenance of healthy gastrointestinal tissue, their depletion by the GGT enzyme is hypothesized to account for the damaging of mammalian cells and the pathophysiology of H. pylori. 相似文献
28.
Aya Nagaoka Hiroyuki Yoshida Sachiko Nakamura Tomohiko Morikawa Keigo Kawabata Masaki Kobayashi Shingo Sakai Yoshito Takahashi Yasunori Okada Shintaro Inoue 《The Journal of biological chemistry》2015,290(52):30910-30923
Regulation of hyaluronan (HA) synthesis and degradation is essential to maintenance of extracellular matrix homeostasis. We recently reported that HYBID (HYaluronan-Binding protein Involved in hyaluronan Depolymerization), also called KIAA1199, plays a key role in HA depolymerization in skin and arthritic synovial fibroblasts. However, regulation of HA metabolism mediated by HYBID and HA synthases (HASs) under stimulation with growth factors remains obscure. Here we report that TGF-β1, basic FGF, EGF, and PDGF-BB commonly enhance total amount of HA in skin fibroblasts through up-regulation of HAS expression, but molecular size of newly produced HA is dependent on HYBID expression levels. Stimulation of HAS1/2 expression and suppression of HYBID expression by TGF-β1 were abrogated by blockade of the MAPK and/or Smad signaling and the PI3K-Akt signaling, respectively. In normal human skin, expression of the TGF-β1 receptors correlated positively with HAS2 expression and inversely with HYBID expression. On the other hand, TGF-β1 up-regulated HAS1/2 expression but exerted only a slight suppressive effect on HYBID expression in synovial fibroblasts from the patients with osteoarthritis or rheumatoid arthritis, resulting in the production of lower molecular weight HA compared with normal skin and synovial fibroblasts. These data demonstrate that although TGF-β1, basic FGF, EGF, and PDGF-BB enhance HA production in skin fibroblasts, TGF-β1 most efficiently contributes to production of high molecular weight HA by HAS up-regulation and HYBID down-regulation and suggests that inefficient down-regulation of HYBID by TGF-β1 in arthritic synovial fibroblasts may be linked to accumulation of depolymerized HA in synovial fluids in arthritis patients. 相似文献
29.
Toshiyuki Fukada Satoru Yamasaki Keigo Nishida Masaaki Murakami Toshio Hirano 《Journal of biological inorganic chemistry》2011,16(7):1123-1134
The essential trace element zinc (Zn) is widely required in cellular functions, and abnormal Zn homeostasis causes a variety
of health problems that include growth retardation, immunodeficiency, hypogonadism, and neuronal and sensory dysfunctions.
Zn homeostasis is regulated through Zn transporters, permeable channels, and metallothioneins. Recent studies highlight Zn’s
dynamic activity and its role as a signaling mediator. Zn acts as an intracellular signaling molecule, capable of communicating
between cells, converting extracellular stimuli to intracellular signals, and controlling intracellular events. We have proposed
that intracellular Zn signaling falls into two classes, early and late Zn signaling. This review addresses recent findings
regarding Zn signaling and its role in physiological processes and pathogenesis. 相似文献
30.
Teno N Gohda K Wanaka K Sueda T Tsuda Y 《Bioorganic & medicinal chemistry letters》2011,21(21):6305-6309
Lysine-nitrile derivatives having a trisubstituted benzene, which belongs to a new chemical class, were prepared and tested for inhibitory activities against plasmin and the highly homologous plasma kallikrein and urokinase. The use of the novel chemotype in the development of plasmin inhibitors has been demonstrated by derivatives of compound 9. 相似文献