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81.
The aim of the present study was to establish a new procedure for the oenological selection of Saccharomyces cerevisiae strains isolated from natural must fermentations of an important Italian grape cultivar, denoted as “Negroamaro”. For this purpose, 108 S. cerevisiae strains were selected as they did not produce H2S and then assayed by microfermentation tests. The adopted procedure made it possible to identify 10 strains that were low producers of acetic acid and hydrogen sulphide and showed that they completed sugar consumption during fermentation. These strains were characterized for their specific oenological and technological properties and, two of them, strains 6993 and 6920, are good candidates as industrial starter cultures. A novel protocol was set up for their biomass production and they were employed for industrial-scale fermentation in two industrial cellars. The two strains successfully dominated the fermentation process and contributed to increasing the wines’ organoleptic quality. The proposed procedure could be very effective for selecting “company-specific” yeast strains, ideal for the production of typical regional wines. “Winery” starter cultures could be produced on request in a small plant just before or during the vintage season and distributed as a fresh liquid concentrate culture.  相似文献   
82.
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   
83.
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   
84.
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   
85.
Carbon monoxide (CO) is a signaling gas produced intracellularly by heme oxygenase (HO) enzymes using heme as a substrate. During heme breakdown, HO-1 and HO-2 release CO, biliverdin, and Fe(2+). In this study, we investigated the effects of manipulation of the HO-1 system in an in vivo model of focal ischemia-reperfusion (FIR) in the rat heart. Male Wistar albino rats, under general anesthesia and artificial ventilation, underwent thoracotomy, the pericardium was opened, and a silk suture was placed around the left descending coronary artery; ischemia was induced by tightening the suture and was monitored for 30 min. Subsequently, the ligature was released to allow reperfusion lasting for 60 min. The first group of rats was sham operated and injected intraperitoneally (i.p.) with saline. The second group underwent FIR. The third group was treated ip 18 hr before FIR with hemin (4 mg/kg). The fourth group was pretreated ip 24 hr before FIR and 6 hr before hemin with zinc protoporphyrin IX (ZnPP-IX, 50 microg/kg). Specimens of the left ventricle were taken for determination of HO expression and activity, infarct size, malonyldialdehyde (MDA) production, and tissue calcium content. FIR led to a significant increase in the generation of MDA and notably raised tissue calcium levels. Induction of HO-1 by hemin significantly decreased infarct size, incidence of reperfusion arrhythmias, MDA generation, and calcium overload induced by FIR. These effects were prevented by the HO-1 inhibitor ZnPP-IX. The present experiments show that the concerted actions of CO, iron, and biliverdin/bilirubin modulate the FIR-induced myocardial injury.  相似文献   
86.
87.
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   
88.

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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89.
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   
90.
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   
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