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991.
Saeko Hamaoka Yoshifumi Naito Hideya Katoh Masaru Shimizu Mao Kinoshita Koichi Akiyama Atsushi Kainuma Kiyoshi Moriyama Ken J. Ishii Teiji Sawa 《Microbiology and immunology》2017,61(2):64-74
Vaccination against the type III secretion system of P. aeruginosa is a potential prophylactic strategy for reducing the incidence and improving the poor prognosis of P. aeruginosa pneumonia. In this study, the efficacies of three different adjuvants, Freund's adjuvant (FA), aluminum hydroxide (alum) and CpG oligodeoxynucleotide (ODN), were examined from the viewpoint of inducing PcrV‐specific immunity against virulent P. aeruginosa. Mice that had been immunized intraperitoneally with recombinant PcrV formulated with one of the above adjuvants were challenged intratracheally with a lethal dose of P. aeruginosa. The PcrV–FA immunized group attained a survival rate of 91%, whereas the survival rates of the PcrV–alum and PcrV–CpG groups were 73% and 64%, respectively. In terms of hypothermia recovery after bacterial instillation, PcrV–alum was the most protective, followed by PcrV–FA and PcrV–CpG. The lung edema index was lower in the PcrV–CpG vaccination group than in the other groups. PcrV–alum immunization was associated with the greatest decrease in myeloperoxidase in infected lungs, and also decreased the number of lung bacteria to a similar number as in the PcrV–FA group. There was less neutrophil recruitment in the lungs of mice vaccinated with PcrV–alum or PcrV–CpG than in those of mice vaccinated with PcrV–FA or PcrV alone. Overall, in terms of mouse survival the PcrV–CpG vaccine, which could be a relatively safe next‐generation vaccine, showed a comparable effect to the PcrV–alum vaccine. 相似文献
992.
GDNF From Human Periodontal Ligament Cells Treated With Pro‐Inflammatory Cytokines Promotes Neurocytic Differentiation of PC12 Cells 下载免费PDF全文
993.
WenBin Xu Atsushi Iwasawa Masato Yayota 《Metabolomics : Official journal of the Metabolomic Society》2017,13(8):90
Introduction
Early experience with low-quality roughage has the potential to improve its utilization in ruminants.Objectives
This study determined the effects of early experience with low-quality roughage on dry matter intake (DMI), body weight (BW) and the hepatic metabolism of lambs.Methods
Ten lambs (3 month old) were randomly allocated to two treatments: the low-quality roughage group (LR) or the control group (C). The study lasted 7 months. In the first 4 months, LR was fed low-quality roughage, whereas C was fed normal roughage. In the last 3 months, both groups were fed low-quality roughage. Dry matter intake (DMI) was determined at the 1st, 3rd, 5th and 7th months (P1, P2, P3 and P4). Analysis of liver tissue metabolomics were carried out in P2 and P3.Results
DMI was greater in LR than C in P1 (p?<?0.05), but did not differ in P2. In P3 and P4, DMI was greater in LR than in C (p?<?0.01). The concentration of five glycolysis/gluconeogenesis intermediates, some lipid metabolism-related metabolites, six amino acids and several amino acid metabolism-related metabolites were different between treatments in P2. From P2 to P3, concentrations of these metabolites changed in LR. However, no difference was found between treatments in P3.Conclusion
Feeding low-quality roughage to lambs early in life influenced hepatic glycolysis/gluconeogenesis, fatty acid oxidation and amino acid metabolism. However, for lambs who had no early experience with low-quality roughage, similar alterations were induced in the liver after 1 month of eating low-quality roughage.994.
Isaias?de?Matos Mour?o Neto Adilson?Luís?Pereira?Silva Auro?Atsushi?Tanaka Jaldyr?de?Jesus Gomes VarelaJr.Email author 《Journal of molecular modeling》2017,23(2):64
This work describes a DFT level theoretical quantum study using the B3LYP functional with the Lanl2TZ(f)/6-31G* basis set to calculate parameters including the bond distances and angles, electronic configurations, interaction energies, and vibrational frequencies of FeTClTAA (iron-tetrachloro-tetraaza[14]annulene), FeTOHTAA (iron-tetrahydroxy-tetraaza[14]annulene), FeTOCH3TAA (iron- tetramethoxy-tetraaza[14]annulene), FeTNH2TAA (iron-tetraamino-tetraaza[14]annulene), and FeTNO2TAA (iron-tetranitro-tetraaza[14]annulene) complexes, as well as their different spin multiplicities. The calculations showed that the complexes were most stable in the triplet spin state (S?=?1), while, after interaction with carbon monoxide, the singlet state was most stable. The reactivity of the complexes was evaluated using HOMO–LUMO gap calculations. Parameter correlations were performed in order to identify the best complex for back bonding (3d xzFe?→?2p xC and 3d yzFe?→?2p zC) with carbon monoxide, and the degree of back bonding increased in the order: FeTNO2TAA?<?FeTClTAA?<?FeTOHTAA?<?FeTOCH3TAA?<?FeTNH2TAA. 相似文献
995.
Calcification process dynamics in coral primary polyps as observed using a calcein incubation method
Yoshikazu Ohno Akira Iguchi Chuya Shinzato Mikako Gushi Mayuri Inoue Atsushi Suzuki Kazuhiko Sakai Takashi Nakamura 《Biochemistry and Biophysics Reports》2017
Calcification processes are largely unknown in scleractinian corals. In this study, live confocal imaging was used to elucidate the spatiotemporal dynamics of the calcification process in aposymbiotic primary polyps of the coral species Acropora digitifera. The fluorophore calcein was used as a calcium deposition marker and a visible indicator of extracellular fluid distribution at the tissue-skeleton interface (subcalicoblastic medium, SCM) in primary polyp tissues. Under continuous incubation in calcein-containing seawater, initial crystallization and skeletal growth were visualized among the calicoblastic cells in live primary polyp tissues. Additionally, the distribution of calcein-stained SCM and contraction movements of the pockets of SCM were captured at intervals of a few minutes. Our experimental system provided several new insights into coral calcification, particularly as a first step in monitoring the relationship between cellular dynamics and calcification in vivo. Our study suggests that coral calcification initiates at intercellular spaces, a finding that may contribute to the general understanding of coral calcification processes. 相似文献
996.
Yusuke Kuroda Shinsuke Yuasa Yasuhide Watanabe Shogo Ito Toru Egashira Tomohisa Seki Tetsuhisa Hattori Seiko Ohno Masaki Kodaira Tomoyuki Suzuki Hisayuki Hashimoto Shinichiro Okata Atsushi Tanaka Yoshiyasu Aizawa Mitsushige Murata Takeshi Aiba Naomasa Makita Tetsushi Furukawa Keiichi Fukuda 《Biochemistry and Biophysics Reports》2017
Andersen-Tawil syndrome (ATS) is a rare inherited channelopathy. The cardiac phenotype in ATS is typified by a prominent U wave and ventricular arrhythmia. An effective treatment for this disease remains to be established. We reprogrammed somatic cells from three ATS patients to generate induced pluripotent stem cells (iPSCs). Multi-electrode arrays (MEAs) were used to record extracellular electrograms of iPSC-derived cardiomyocytes, revealing strong arrhythmic events in the ATS-iPSC-derived cardiomyocytes. Ca2+ imaging of cells loaded with the Ca2+ indicator Fluo-4 enabled us to examine intracellular Ca2+ handling properties, and we found a significantly higher incidence of irregular Ca2+ release in the ATS-iPSC-derived cardiomyocytes than in control-iPSC-derived cardiomyocytes. Drug testing using ATS-iPSC-derived cardiomyocytes further revealed that antiarrhythmic agent, flecainide, but not the sodium channel blocker, pilsicainide, significantly suppressed these irregular Ca2+ release and arrhythmic events, suggesting that flecainide's effect in these cardiac cells was not via sodium channels blocking. A reverse-mode Na+/Ca2+exchanger (NCX) inhibitor, KB-R7943, was also found to suppress the irregular Ca2+ release, and whole-cell voltage clamping of isolated guinea-pig cardiac ventricular myocytes confirmed that flecainide could directly affect the NCX current (INCX). ATS-iPSC-derived cardiomyocytes recapitulate abnormal electrophysiological phenotypes and flecainide suppresses the arrhythmic events through the modulation of INCX. 相似文献
997.
998.
Feeding response of two copepods Neocalanus flemingeri and Calanus sinicus on cultures of three life-forms; vegetative cells, resting spores and resting cells, of Chaetoceros pseudocurvisetus was investigated. N. flemingeri fed heavily on the vegetative cells but scarcely responded to feed on the resting spores. C. sinicus showed significantly higher filtering rate on the vegetative cells and resting cells than on the resting spores. Survival of the three life-forms of C. pseudocurvisetus after gut passage of the copepods was also studied. The resting spores could germinate from fecal pellets of both N. flemingeri and C. sinicus; however, both the vegetative cells and the resting cells could not survive ingestion by the copepods. These results suggest that resting spore forming diatoms, such as C. pseudocurvisetus form spores which have a low nutritional value and during gut passage are largely indigestible due to the heavily silicified frustules and thus minimize the effects of grazing by copepods. 相似文献
999.
1000.
Sennertia mites live as inquilines in the nests of carpenter bees and disperse as deutonymphs on newly emerged adult bees. Because their life cycle is tightly linked to that of the host bees, Sennertia may diverge in response to speciation in the hosts. However, the majority of Sennertia species are associated with several closely related carpenter bees, suggesting that host speciation may not be reflected in mite genetic structure. Here we investigate the extent of host-associated genetic differentiation in two Sennertia mites (S. alfkeni and S. japonica) that share four closely related, strictly allopatric large carpenter bees (Xylocopa). Analysis of the mitochondrial cytochrome oxidase subunit I (COI) gene in Sennertia unexpectedly indicates that the two species represent morphological variants of a single species, and they collectively group into four distinct, allopatric clades that are uniquely associated with a single Xylocopa host. An exception is the mites associated with X. amamensis of the northernmost populations, which have genotypes typical of those associated with neighboring X. appendiculatacircumvolans. Additional analysis using amplified fragment length polymorphism (AFLP) further corroborates the presence of four mite clades but contrary to the COI data, suggests that the mites of the southernmost population of X. appendiculatacircumvolans have genetic profiles typical of those associated with X. amamensis. These results indicate that some mites have undergone secondary host switch after the formation of the four mite lineages and further experienced mitochondrial introgression during period of lineage coexistence. Overall, our results strongly urge reappraisal of deutonymph-based mite taxonomy and illuminate the importance of host-associated divergence during incipient stage of speciation in chaetodactylid mites. Furthermore, the occurrence of host switch and introgression between genetically differentiated mites entails that two host species have co-occurred in the past, thus providing a unique source of evidence for migration and competitive exclusion between the presently allopatric Xylocopa hosts. 相似文献