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21.
Nakagami H Nishikawa T Tamura N Maeda A Hibino H Mochizuki M Shimosato T Moriya T Morishita R Tamai K Tomono K Kaneda Y 《Journal of cellular and molecular medicine》2012,16(7):1629-1639
We previously identified a novel angiogenic peptide, AG30, with antibacterial effects that could serve as a foundation molecule for the design of wound-healing drugs. Toward clinical application, in this study we have developed a modified version of the AG30 peptide characterized by improved antibacterial and angiogenic action, thus establishing a lead compound for a feasibility study. Because AG30 has an α-helix structure with a number of hydrophobic and cationic amino acids, we designed a modified AG30 peptide by replacing several of the amino acids. The replacement of cationic amino acids (yielding a new molecule, AG30/5C), but not hydrophobic amino acids, increased both the angiogenic and the antimicrobial properties of the peptide. AG30/5C was also effective against methicillin-resistant Staphylococcus aureus (MRSA) and antibiotic-resistant Pseudomonas aeruginosa. In a diabetic mouse wound-healing model, the topical application of AG30/5C accelerated wound healing with increased angiogenesis and attenuated MRSA infection. To facilitate the eventual clinical investigation/application of these compounds, we developed a large-scale procedure for the synthesis of AG30/5C that employed the conventional solution method and met Good Manufacturing Practice guidelines. In the evaluation of stability of this peptide in saline solution, RP-HPLC analysis revealed that AG30/5C was fairly stable under 5°C for 12 months. Therefore, we propose the use of AG30/5C as a wound-healing drug with antibacterial and angiogenic actions. 相似文献
22.
Sakurai H Nishi A Sato N Mizukami J Miyoshi H Sugita T 《Biochemical and biophysical research communications》2002,297(5):1277-1281
TAK1 mitogen-activated protein kinase kinase kinase (MAP3K) is activated by its specific activator, TAK1-binding protein 1 (TAB1). A constitutively active TAK1 mutant has not yet been generated due to the indispensable requirement of TAB1 for TAK1 kinase activity. In this study, we generated a novel constitutively active TAK1 by fusing its kinase domain to the minimal TAK1-activation domain of TAB1. Co-immunoprecipitation assay demonstrated that these domains interacted intra-molecularly. The TAK1-TAB1 fusion protein showed a significant MAP3K activity in vitro and activated c-Jun N-terminal kinase/p38 MAPKs and IkappaB kinase in vivo, which was followed by increased production of interleukin-6. These results indicate that the fusion protein is useful for characterizing the physiological roles of the TAK1-TAB1 complex. 相似文献
23.
Kaori Bonkohara Maiko Fuji Akito Nakao Noriyuki Igura 《Bioscience, biotechnology, and biochemistry》2016,80(3):533-539
To prepare an aroma mixture of Japanese soy sauce by fewest components, the aroma concentrate of good sensory attributes was prepared by polyethylene membrane extraction, which could extract only the volatiles with diethyl ether. GC-MS-Olfactometry was done with the aroma concentrate, and 28 odor-active compounds were detected. Application of aroma extract dilution analysis to the separated fraction revealed high flavor dilution factors with respect to acetic acid, 4-hydroxy-2(or5)-ethyl-5(or2)-methyl-3(2H)-furanone (HEMF), 3-methyl-1-butanol (isoamyl alcohol), and 3-(methylsulfanyl)propanal (methional). A model aroma mixture containing above four odorants showed a good similarity with the aroma of the soy sauce itself. Consequently, the reminiscent aroma mixture of soy sauce was prepared in water. The ratio of acetic acid, HEMF, isoamyl alcohol, and methional was 2500:300:100:1. 相似文献
24.
Naito AT Sumida T Nomura S Liu ML Higo T Nakagawa A Okada K Sakai T Hashimoto A Hara Y Shimizu I Zhu W Toko H Katada A Akazawa H Oka T Lee JK Minamino T Nagai T Walsh K Kikuchi A Matsumoto M Botto M Shiojima I Komuro I 《Cell》2012,149(6):1298-1313
Wnt signaling plays critical roles in development of various organs and pathogenesis of many diseases, and augmented Wnt signaling has recently been implicated in mammalian aging and aging-related phenotypes. We here report that complement C1q activates canonical Wnt signaling and promotes aging-associated decline in tissue regeneration. Serum C1q concentration is increased with aging, and Wnt signaling activity is augmented during aging in the serum and in multiple tissues of wild-type mice, but not in those of C1qa-deficient mice. C1q activates canonical Wnt signaling by binding to Frizzled receptors and subsequently inducing C1s-dependent cleavage of the ectodomain of Wnt coreceptor low-density lipoprotein receptor-related protein 6. Skeletal muscle regeneration in young mice is inhibited by exogenous C1q treatment, whereas aging-associated impairment of muscle regeneration is restored by C1s inhibition or C1qa gene disruption. Our findings therefore suggest the unexpected role of complement C1q in Wnt signal transduction and modulation of mammalian aging. 相似文献
25.
Poly(ethylene glycol)-conjugated human serum albumin including iron porphyrins: surface modification improves the O2-transporting ability 总被引:2,自引:0,他引:2
Artificial O2-carrying hemoprotein composed of human serum albumin including tetrakis(o-amidophenyl)porphinatoiron(II) (Fe4P or Fe3P) [HSA-FeXP] has been modified by maleimide- or succinimide-terminated poly(ethylene glycol) (PEG), and the formed PEG bioconjugates have been physicochemically characterized. 2-Iminothiolane (IMT) reacted with the amino groups of Lys to create active thiol groups, which bind to alpha-maleimide-omega-methoxy PEG [Mw: 2-kDa (PEG(M2)), 5-kDa (PEG(M5))]. On the other hand, alpha-succinimidyl-omega-methoxy PEG [Mw: 2-kDa (PEG(S2)), 5-kDa (PEG(S5))] directly binds to Lys residues. MALDI-TOF MS of the PEG-conjugated HSA-FeXP showed distinct molecular ion peaks, which provide an accurate number of the PEG chains. In the case of PEG(MY)(HSA-FeXP), the spectroscopic assay of the thiol groups also provided the mean of the binding numbers of the polymers, and the degree of the modification was controlled by the ratio of [IMT]/[HSA]. The viscosity and colloid osmotic pressures of the 2-kDa PEG conjugates (phosphate-buffered saline solution, [HSA] = 5 g dL(-1)) were almost the same as that of the nonmodified one, whereas the 5-kDa PEG binding increased the rheological parameters. The presence of flexible polymers on the HSA surface retarded the association reaction of O2 to FeXP and stabilized the oxygenated complex. Furthermore, PEG(MY)(HSA-FeXP) exhibited a long circulation lifetime of FeXP in rats (13-16 h). On the basis of these results, it can be concluded that the surface modification of HSA-FeXP by PEG has improved its comprehensive O2-transporting ability. In particular the PEG(MY)(HSA-FeXP) solution could be a promising material for entirely synthetic O2-carrying plasma expander as a red cell substitute. 相似文献
26.
Sompong Chankaew Prakit Somta Takehisa Isemura Norihiko Tomooka Akito Kaga Duncan A. Vaughan Peerasak Srinives 《Molecular breeding : new strategies in plant improvement》2013,32(1):121-130
Powdery mildew (PM) is a common and serious disease of mungbean [Vigna radiata (L.) Wilczek]. A few quantitative trait loci (QTL) for PM resistance in mungbean have been reported. The objective of this study was to locate QTL for PM resistance in two resistant accessions V4718 and RUM5. Simple sequence repeat markers were analyzed in an F2 population from a cross between Kamphaeng Saen 1 (KPS1; susceptible to PM) and V4718 (resistant to PM), and in F2 and BC1F1 populations from a cross between Chai Nat 60 (CN60; susceptible to PM) and RUM5 (resistant to PM). Progenies of 134 F2:3 and F2:4 lines derived from KPS1 × V4718, and 190 F2:3 and 74 BC1F1:2 lines derived from CN60 × RUM5 and CN60 × (CN60 × RUM5), respectively, were evaluated for response to PM under field conditions. Multiple interval mapping identified a major QTL on linkage group (LG) 9 and two minor QTL on LG4 for the resistance in V4718, and detected two major QTL on LG6 and LG9 and one minor QTL on LG4 for the resistance in RUM5. Comparative linkage analysis of the QTL for PM resistance in this study and in previous reports suggests that the resistance QTL on LG9 in V4718, RUM5, ATF3640 and VC6468-11-1A are the same locus or linked. One QTL on LG4 is the same in three sources (V4718, RUM5 and VC1210A). Another QTL on LG6 is the same in two sources (RUM5 and VC6468-11-1A). In addition, one QTL in V4718 on LG4 appears to be a new resistance locus. These different resistance loci will be useful for breeding durably PM-resistant mungbean cultivars. 相似文献
27.
Twelve polyether compounds originating from dinoflagellates were tested for growth-inhibiting activities againstAspergillus niger, Penicillium funiculosum, Candida rugosa, Escherichia coli, Bacillus megaterium andStaphylococcus aureus by a paper disc method. These polyethers represent six groups of different skeletons and originate from three species;Prorocentrum lima, Dinophysis fortii andGambierdiscus toxicus. Potent antifungal activities were observed with okadaic acid and its two congeners, desulfated yessotoxin, and ciguatoxin but not with okadaic acid esters, prorocentrolide, pectenotoxin-1, yessotoxin, maitotoxin, and desulphated maitotoxin. The antifungal activities and mouse lethalities of the polyethers were markedly affected by slight modification of their structures. Antibacterial potency of the tested compounds was not significant. 相似文献
28.
The endemic Hawaiian moth genus Hyposmocoma includes 348 described species and perhaps twice as many that remain undescribed. The genus is unusual within Lepidoptera in that its larvae create distinctive silk cases in which they perambulate while protected and camouflaged. An extraordinary diversity of case types exists, and to date more than ten different types have been identified, each corresponding roughly to a separate evolutionary lineage. In this study, we describe three new species of Hyposmocoma: Hyposmocoma ipohapuusp. n. from Big Island, Hyposmocoma makawaosp. n. from Makawao Forest Reserve in Mauiand Hyposmocoma tantalasp. n. from Mt. Tantalus, Oahu, all of which produce tubular purse cases during their larval stage. We also describe the female of Hyposmocoma inversella Walsingham, which was previously undescribed, and re-describe two closely related species, Hyposmocoma auropurpurea Walsingham and Hyposmocoma nebulifera Walsingham, neither which have been formally described in recent years. We present for the first time, primer sequences for a 705 bp fragment of CAD, designed for Hyposmocoma and relatives. The molecular phylogeny based on mitochondrial and nuclear loci demonstrates that all are distinct species. The discovery of a new, endemic species from Mt. Tantalus, an area with many invasive species, suggests that even relatively degraded areas in Hawaii would be worthy of active conservation efforts. 相似文献
29.
Role of Caribbean Islands in the diversification and biogeography of Neotropical Heraclides swallowtails 下载免费PDF全文
Delano S. Lewis Felix A. H. Sperling Shinichi Nakahara Adam M. Cotton Akito Y. Kawahara Fabien L. Condamine 《Cladistics : the international journal of the Willi Hennig Society》2015,31(3):291-314
Numerous hypotheses on the evolution of Neotropical biodiversity have stimulated research to provide a better understanding of diversity dynamics and distribution patterns of the region. However, few studies integrate molecular and morphological data with complete sampling of a Neotropical group, and so there has been little synthesis of the multiple processes governing biodiversity through space and time. Here, a total‐evidence phylogenetic approach is used to reconstruct the evolutionary history of the butterfly subgenus Heraclides. We used DNA sequences for two mitochondrial genes and one nuclear gene and coded 133 morphological characters of larvae and adults. A robust and well‐resolved phylogeny was obtained using several analytical approaches, while molecular dating and biogeographical analyses indicated an early Miocene origin (22 Mya) in the Caribbean Islands. We inferred six independent dispersal events from the Caribbean to the mainland, and three from the mainland to the Caribbean, and we suggest that cooling climates with decreasing sea levels may have contributed to these events. The time‐calibrated tree is best explained by a museum model of diversity in which both speciation and extinction rates remained constant through time. By assessing both continental and fine‐scale biodiversity patterns, this study provides new findings, for instance that islands may act as source of diversity rather than as a sink, to explain spatio‐temporal macroevolutionary processes within the Neotropical region. 相似文献
30.
The vasopressin (VP)/oxytocin (OT) superfamily peptides are one of the most widely distributed neuropeptides and/or neurohypophysial hormones, but have ever not been characterized from any deuterostome invertebrates including protochordates, ascidians. In the present study, we show the identification of a novel VP/OT superfamily peptide and its receptor in the ascidian, Ciona intestinalis. Intriguingly, the Ciona VP/OT-related peptide (Ci-VP), unlike other 9-amino acid and C-terminally amidated VP/OT superfamily peptides, consists of 13 amino acids and lacks a C-terminal amidation. Mass spectrometry confirmed the presence of the 13-residue Ci-VP in the neural complex. Furthermore, 10 of 14 cysteines are conserved in the neurophysin domain, compared with other VP/OT counterparts. These results revealed that the VP/OT superfamily is conserved in ascidians, but the Ci-VP gene encodes an unprecedented VP/OT-related peptide and neurophysin protein. Ci-VP was also shown to activate its endogenous receptor, Ci-VP-R, at physiological concentrations, confirming the functionality of Ci-VP as an endogenous ligand. The Ci-VP gene was expressed exclusively in neurons of the brain, whereas the Ci-TK-R mRNA was distributed in various tissues including the neural complex, alimentary tract, gonad, and heart. These expression profiles suggest that Ci-VP, like other VP/OT superfamily peptides, serves as a multifunctional neuropeptides. Altogether, our data revealed both evolutionary conservation and specific divergence of the VP/OT superfamily in protochordates. This is the first molecular characterization of a VP/OT superfamily peptide and its cognate receptor from not only ascidians but also deuterostome invertebrates. 相似文献