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1.
East Asian species of the genera Hybrizon and Ghilaromma are reviewed. Four species of Hybrizon, H. buccatus (Brébisson 1825), H. ghilarovi Tobias, 1988, H. juncoi (Ceballos 1957) and H. flavofacialis Tobias, 1988 and two species of Ghilaromma, G. orientalis Tobias, 1988 and G. ussuriensis Tobias, 1988, were recognized. H. ghilarovi was recorded from Korea, Japan and China, while H. juncoi was recorded from Korea, for the first time. The specimens recorded from Japan as G. fuliginosi (Wilkinson, 1930) by Watanabe (1984) are referred to G. orientalis herein. This species is newly recorded from Korea and Japan. Keys to East Asian species of Hybrizon and the world species of Ghilaromma are also provided.  相似文献   
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A role for Wnt signal transduction in the development and maintenance of brain structures is widely acknowledged. Recent studies have suggested that Wnt signaling may be essential for synaptic plasticity and neurotransmission. However, the direct effect of a Wnt protein on synaptic transmission had not been demonstrated. Here we show that nanomolar concentrations of purified Wnt3a protein rapidly increase the frequency of miniature excitatory synaptic currents in embryonic rat hippocampal neurons through a mechanism involving a fast influx of calcium from the extracellular space, induction of post-translational modifications on the machinery involved in vesicle exocytosis in the presynaptic terminal leading to spontaneous Ca2+ transients. Our results identify the Wnt3a protein and a member of its complex receptor at the membrane, the low density lipoprotein receptor-related protein 6 (LRP6) coreceptor, as key molecules in neurotransmission modulation and suggest cross-talk between canonical and Wnt/Ca2+ signaling in central neurons.  相似文献   
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Protein crystallographers are often confronted with recalcitrant proteins not readily crystallizable, or which crystallize in problematic forms. A variety of techniques have been used to surmount such obstacles: crystallization using carrier proteins or antibody complexes, chemical modification, surface entropy reduction, proteolytic digestion, and additive screening. Here we present a synergistic approach for successful crystallization of proteins that do not form diffraction quality crystals using conventional methods. This approach combines favorable aspects of carrier‐driven crystallization with surface entropy reduction. We have generated a series of maltose binding protein (MBP) fusion constructs containing different surface mutations designed to reduce surface entropy and encourage crystal lattice formation. The MBP advantageously increases protein expression and solubility, and provides a streamlined purification protocol. Using this technique, we have successfully solved the structures of three unrelated proteins that were previously unattainable. This crystallization technique represents a valuable rescue strategy for protein structure solution when conventional methods fail.  相似文献   
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A protocol for in vitro propagation from pseudobulb sections of Lycaste armomatica (Graham ex Hook) Lindl., an ornamental and fragrant orchid, was developed. The effect of four cytokinins: kinetin (K), meta-topolin (mT), N 6-benzyladenine (BA), and thidiazuron (TDZ), in equimolar concentrations, was investigated. Shoot formation from apical and basal pseudobulb sections was obtained in all treatments. A few medial sections cultured in media supplemented with BA formed protocorm-like bodies. Shoot formation was greater from the basal section than the apical, and mainly occurred in explants cultured in media containing TDZ. The highest average numbers of shoots per explant were achieved from basal sections cultured in media supplemented with TDZ at 4.4, 8.87 and 2.2 μM, forming on average 9.9, 8.6 and 7.3 shoots per explant, respectively. Since the medial pseudobulb section was the worst explant for propagation of L. aromatica, we recommend that pseudobulbs be divided into two sections; the basal half should be cultured in MS medium supplemented with TDZ at 4.4 μM and the apical half with TDZ at 2.2 μM. Subculturing individual shoots in MS medium without plant growth regulators allows further development and rooting. A survival rate of more than 90% under greenhouse conditions was achieved. This research represents a direct contribution to the conservation and sustainable use of this valuable natural resource.  相似文献   
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Microglia are main form of active immune defense, and they are constantly moving and analyzing the CNS for damaged neurons and infectious agents. In this study, we compared microglia in the spinal cord of the young adult (1–2 years old) and aged (10–12 years old) German Shepherd dogs via immunohistochemistry and western blot analysis for ionized calcium-binding adapter molecule 1 (Iba-1), a microglial marker. In addition, we also observed the interferon-γ (IFN-γ), a pro-inflammatory cytokine, and interleukin-1β (IL-1β), produced by activated microglia/macrophage, protein levels in these groups. At first, we found that neuronal nuclei (NeuN, a neuronal marker)-immunoreactive neurons were distributed throughout the grey mate of the spinal cord, and there were no significant differences between the adult and aged groups. Most of Iba-1-immunoreactive microglia were morphologically ramified microglia (resting form) in the adult group, while some Iba-1-immunoreactive microglia were morphologically activated microglia in the aged group. In western blot analysis, Iba-1, IFN-γ and IL-1β expression were increased in the aged group. This result may be associated with age-dependent changes in the spinal cord.  相似文献   
8.
Mucus hypersecretion is a clinically important manifestation of chronic inflammatory airway diseases, such as asthma and Chronic obstructive pulmonary disease (COPD). Mucin production in airway epithelia is increased under conditions of oxidative stress. Src homology 2 domain-containing protein tyrosine phosphatase (SHP)-1 suppression is related to the development of airway inflammation and increased ROS levels. In this study, we investigated the role of SHP-1 in mucin secretion triggered by oxidative stress. Human lung mucoepidermoid H292 carcinoma cells were transfected with specific siRNA to eliminate SHP-1 gene expression. Cultured cells were treated with hydrogen peroxide (H2O2), and Mucin 5AC(MUC5AC) gene expression and mucin production were determined. Activation of p38 mitogen activated protein kinase (MAPK) in association with MUC5AC production was evaluated. N-acetylcysteine (NAC) was employed to determine whether antioxidants could block MUC5AC production. To establish the precise role of p38, mucin expression was observed after pre-treatment of SHP-1-depleted H292 cells with the p38 chemical blocker. We investigated the in vivo effects of oxidative stress on airway mucus production in SHP-1-deficient heterozygous (mev/+) mice. MUC5AC expression was enhanced in SHP-1 knockdown H292 cells exposed to H2O2, compared to that in control cells. The ratio between phosphorylated and total p38 was significantly increased in SHP-1-deficient cells under oxidative stress. Pre-treatment with NAC suppressed both MUC5AC production and p38 activation. Blockage of p38 MAPK led to suppression of MUC5AC mRNA expression. Notably, mucin production was enhanced in the airway epithelia of mev/+ mice exposed to oxidative stress. Our results clearly indicate that SHP-1 plays an important role in airway mucin production through regulating oxidative stress.  相似文献   
9.
It is well known that music can have calming effects on humans, other mammals and birds. Reducing environmental stress or enhancing the resistance to certain stressors has been shown to extend lifespan in several organisms. Evidence also suggests that mild temporary stress may also enhance stress resistance and ultimately slow the aging process. This study explored the possibility that music may influence the lifespan of the fruit fly Drosophila melanogaster, possibly by affecting responses to stress. Flies received either background sounds (control), or background sounds supplemented with music (experimental). The experimental group had classical music playing constantly at an average of 20 dB above background sound. The median lifespan of females receiving music was 42 days compared to the median of 45 days without music, but the difference was not significant. For males median lifespans were 42 days with music exposure, and 47 days without music and the difference was significant. These results suggest that exposure to classical music decreased the lifespan of male Drosophila. Both experimental and control populations showed age-dependent increases in mortality, indicating that music affects the normal aging process rather than showing overt toxicity. These results suggest that certain auditory stimuli may be stressful and can be used as insect management.  相似文献   
10.
A recombinant DNA, encoding the chimeric protein of the signal sequence for bifidobacterial α-amylase mature pediocin PA-1, was introduced into Bifidobacterium longum MG1. Biologically active pediocin PA-1 was successfully secreted from the strain and showed bactericidal activity against Listeria monocytogenes and the same molecular mass as native pediocin PA-1.  相似文献   
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