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81.
Hot pepper fruits (Capsicum annuum L.) var. Bronowicka Ostra have been studied with regard to content of flavonoids and other phenolics. Nine compounds were isolated from pericarp of pepper fruits by preparative HPLC. Their structures were identified by chromatographic (analytical HPLC) and spectroscopic (UV, NMR) techniques. Two of the identified compounds, trans-p-ferulylalcohol-4-O-(6-(2-methyl-3-hydroxypropionyl) glucopyranoside and luteolin-7-O-(2-apiofuranosyl-4-glucopyranosyl-6-malonyl)-glucopyranoside were found for the first time in the plant kingdom. Additionally compounds: trans-p-feruloyl-beta-D-glucopyranoside, trans-p-sinapoyl-beta- D-glucopyranoside, quercetin 3-O-alpha-L-rhamnopyranoside-7-O-beta-D-glucopyranoside, luteolin 6-C-beta-D-glucopyranoside-8-C-alpha-L-arabinopyranoside, apigenin 6-C-beta-D-glucopyranoside-8-C-alpha-L-arabinopyranoside and luteolin 7-O-[2-(beta-D-apiofuranosyl)-beta-D-glucopyranoside] were found for the first time in pepper fruit Capsicum annuum L.  相似文献   
82.
The effect of a copper amine oxidase (histaminase) purified from the pea seedling as free or immobilized enzyme on the response to specific antigen was studied in isolated hearts from actively sensitized guinea pigs. In vitro challenge with the specific antigen of hearts from actively sensitized animals evokes a positive inotropic and chronotropic effect, a coronary constriction, followed by dilation and an increase in the amount of histamine and nitrites, the oxidation product of nitric oxide, in the perfusates. In the presence of both forms of histaminases, the positive inotropic and chronotropic responses as well as the coronary constriction and the release of histamine were fully blocked. The amount of nitrites, appearing in the perfusates when anaphylaxis is elicited in the presence of both forms of histaminases, is significantly increased, as well as nitric oxide synthase activity and cyclic GMP content in cardiac tissue, while cardiac calcium overload was significantly prevented. These observations demonstrate that the decrease in the anaphylactic release of histamine and the subsequent abatement of the cardiac response to antigen can be accounted for by the inactivation by histaminase of the released histamine and by a stimulation of endogenous nitric oxide production.  相似文献   
83.
The homeobox gene Not is highly conserved in Xenopus, chicken and zebrafish with an apparent role in notochord formation, which inspired the name of this distinct subfamily. Interestingly, Not genes are also well conserved in animals without notochord such as sea urchins, Drosophila or even Hydra, but appear to be highly derived in mammals. A search for homeobox genes in the placozoan Trichoplax adhaerens, one of the simplest organisms available today, revealed only two homeobox genes: a Not homologue and the previously described gene Trox-2, which is most similar to the Gsx subfamily of the Hox/ParaHox cluster genes. Not has a unique expression profile in Trichoplax. It is highly expressed in folds of intact animals and in the wounds of regenerating animals. The dynamic expression pattern of Trichoplax Not is discussed in comparison with the invariable expression pattern of Trox-2 and the putative secreted protein Secp1. The high sequence conservation of Not from Trichoplax to lower vertebrates, but not to mammals, represents a rare example of an apparent gene decay in the lineage leading to humans.  相似文献   
84.
85.
Four flavonoids namely (2R,3R)-2,3-trans-7,4'-dimethoxydihydroflavonol, (2R,3S,4S)-2,3-trans-3,4-cis-7,4'-dimethoxy-3,4-flavandiol, 6-hydroxy-7,4'-dimethoxyflavone, 6,7,4'-trimethoxyflavone, along with the known isoflavonoids ferreirin, dihydrocajanin, dalbergioidin, dihydrobiochanin A and biochanin A and other 11 known compounds were isolated from the roots of Gynerium sagittatum. The structural characterization of these compounds was carried out via one- and two-dimensional NMR experiments in combination with ESI-MS. Finally a quantitative analysis of the isoflavones of the methanolic extract was performed by LC-ESI-MS. The high quantity of isoflavonoids found in G. sagittatum makes this plant a good natural source of isoflavonoids.  相似文献   
86.

The maintenance of genome integrity is ensured by proper chromosome inheritance during mitotic and meiotic cell divisions. The chromosomal counterpart responsible for chromosome segregation to daughter cells is the centromere, at which the spindle apparatus attaches through the kinetochore. Although all mammalian centromeres are primarily composed of megabase-long repetitive sequences, satellite-free human neocentromeres have been described. Neocentromeres and evolutionary new centromeres have revolutionized traditional knowledge about centromeres. Over the past 20 years, insights have been gained into their organization, but in spite of these advancements, the mechanisms underlying their formation and evolution are still unclear. Today, through modern and increasingly accessible genome editing and long-read sequencing techniques, research in this area is undergoing a sudden acceleration. In this article, we describe the primary sequence of a previously described human chromosome 3 neocentromere and observe its possible evolution and repair results after a chromosome breakage induced through CRISPR-Cas9 technologies. Our data represent an exciting advancement in the field of centromere/neocentromere evolution and chromosome stability.

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87.
Microscopy techniques can readily visualize the finest details of embryo vasculature, but still lack to provide a complete three‐dimensional representation of blood flow parameters. We present an in‐vivo 3D imaging technique, able to reconstruct the blood cell velocity vector over a large volume of zebrafish embryos. This low cost and relatively simple technique is exploited to quantitatively assess blood velocity in the zebrafish tail at different stages of development. (© 2013 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)  相似文献   
88.
The Notch signaling pathway, which plays a critical role in cell-fate decisions throughout development, is regulated by endocytosis of both the ligand and receptor. Endocytosis of the Drosophila ligands, Delta and Serrate, is required in the signaling cell for signal initiation and requires one of two ubiquitin ligases, Neuralized or Mind bomb. Through in vitro binding assays we have identified an interaction between Neuralized and phosphoinositides, modified membrane lipids that mediate membrane trafficking and signaling. We show that interactions between phosphoinositides and Neuralized contribute to the membrane localization of Neuralized in the absence of Delta, and that the phosphoinositide-binding motif is required for Neuralized to endocytose Delta downstream of Delta ubiquitination. Lastly, we provide evidence that this interaction may also be important for vertebrate Neuralized function. These results demonstrate that, through interactions with Neuralized, phosphoinositides may regulate Delta endocytosis and, by extension, Notch signal transduction.  相似文献   
89.
90.
Several studies suggest that sociocultural models conveying extreme thinness as the widespread ideal of beauty exert an important influence on the perceptual and emotional representation of body image. The psychological mechanisms underlying such environmental influences, however, are unclear. Here, we utilized a perceptual adaptation paradigm to investigate how perceptual experience modulates body esthetic appreciation. We found that the liking judgments of round bodies increased or decreased after brief exposure to round or thin bodies, respectively. No change occurred in the liking judgments of thin bodies. The results suggest that perceptual experience may shape our esthetic appreciation to favor more familiar round body figures. Importantly, individuals with more deficits in interoceptive awareness were less prone to increase their liking ratings of round bodies after exposure, suggesting a specific risk factor for the susceptibility to the influence of the extreme thin vs. round body ideals of beauty portrayed by the media.  相似文献   
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