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61.
Antonio Evidente Anna Andolfi Alessio Cimmino Sonia Ganassi Claudio Altomare Mara Favilla Antonio De Cristofaro Silvia Vitagliano Maria Agnese Sabatini 《Journal of chemical ecology》2009,35(5):533-541
We report the effects of some bisorbicillinoids isolated from biomass of the fungus Trichoderma citrinoviride on settling and feeding preference of the aphid Schizaphis graminum. Purification of the fungal metabolites was carried out by a combination of column chromatography and thin-layer chromatography
using direct and reverse phases. Chemical identification was performed by spectroscopic methods including nuclear magnetic
resonance and mass spectrometry. The identified bisorbicillinoids appeared to be bislongiquinolide, its 16,17-dihydro derivative,
trichodimerol, and dihydrotrichodimerol. A feeding preference test with alate morphs of S. graminum was used to identify the active fractions. Among the four bisorbicillinoids, dihydrotrichodimerol and bislongiquinolide influenced
aphid feeding preference, restraining specimens from settling on leaves treated with metabolites. Taste neurons sensitive
to these compounds, particularly to bislongiquinolide, were located on tarsi of the S. graminum alate morphs. 相似文献
62.
Christian Müller Dr. Maria Antonia Gomez‐Zurita Frau Dr. Dario Ballinari Dr. Sonia Colombo Dr. Alessandro Bitto Dr. Enzo Martegani Prof. Cristina Airoldi Dr. Anske Stephanie van Neuren Dr. Matthias Stein Dr. Jörg Weiser Dr. Carlo Battistini Dr. Francesco Peri Prof. 《ChemMedChem》2009,4(4):524-528
A panel of new potential Ras ligands was generated by decorating a tricyclic levoglucosenone‐derived scaffold with aromatic moieties. Some members of the panel show in vitro inhibitory activity toward the nucleotide exchange process on Ras and are toxic to some human cancer cell lines.
63.
Dietary fiber and antioxidants are food constituents and functional ingredients that are generally addressed separately. Nowadays there is scientific evidence that primary characteristics of DF assigned to non starch polysaccharides and lignin (resistance to digestion and absorption in the small intestine and fermentation in the large intestine) can be extended to other indigestible food constituents that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine. The antioxidant dietary fiber concept was defined as a dietary fiber concentrate containing significant amounts of natural antioxidants associated with non digestible compounds. Hibiscus sabdariffa L flower shows in its composition an important percentage of dietary fiber and high antioxidant capacity. The infusion obtained by decoction of flowers, had been extensibility studied due to the healthy properties. In this work the principal nutritional aspects from Hibiscus sabdariffa L and its use as a possible antioxidant dietary fiber source had been considered. 相似文献
64.
Margaux Wieckowski Stphanie Ranga Delphine Moison Sbastien Messiaen Sonia Abdallah Sylvie Granon Ren Habert Virginie Rouiller-Fabre Gabriel Livera Marie-Justine Guerquin 《International journal of molecular sciences》2021,22(21)
For decades, numerous chemical pollutants have been described to interfere with endogenous hormone metabolism/signaling altering reproductive functions. Among these endocrine disrupting substances, Bisphenol A (BPA), a widely used compound, is known to negatively impact germ and somatic cells in the testis. Physical agents, such as ionizing radiation, were also described to perturb spermatogenesis. Despite the fact that we are constantly exposed to numerous environmental chemical and physical compounds, very few studies explore the impact of combined exposure to chemical and physical pollutants on reproductive health. The aim of this study was to describe the impact of fetal co-exposure to BPA and IR on testicular function in mice. We exposed pregnant mice to 10 µM BPA (corresponding to 0.5 mg/kg/day) in drinking water from 10.5 dpc until birth, and we irradiated mice with 0.2 Gy (γ-ray, RAD) at 12.5 days post-conception. Co-exposure to BPA and γ-ray induces DNA damage in fetal germ cells in an additive manner, leading to a long-lasting decrease in germ cell abundance. We also observed significant alteration of adult steroidogenesis by RAD exposure independently of the BPA exposure. This is illustrated by the downregulation of steroidogenic genes and the decrease of the number of adult Leydig cells. As a consequence, courtship behavior is modified, and male ultrasonic vocalizations associated with courtship decreased. In conclusion, this study provides evidence for the importance of broadening the concept of endocrine disruptors to include physical agents, leading to a reevaluation of risk management and regulatory decisions. 相似文献
65.
Sonia Maatoug Amani Cheikh Oussema Khamessi Hager Tabka Zied Landoulsi Jean-Marie Guigonis Sylvie Diochot Saïd Bendahhou Rym Benkhalifa 《International journal of molecular sciences》2021,22(22)
The voltage-gated K+ channels Kv3.1 display fast activation and deactivation kinetics and are known to have a crucial contribution to the fast-spiking phenotype of certain neurons. AahG50, as a natural product extracted from Androctonus australis hector venom, inhibits selectively Kv3.1 channels. In the present study, we focused on the biochemical and pharmacological characterization of the component in AahG50 scorpion venom that potently and selectively blocks the Kv3.1 channels. We used a combined optimization through advanced biochemical purification and patch-clamp screening steps to characterize the peptide in AahG50 active on Kv3.1 channels. We described the inhibitory effect of a toxin on Kv3.1 unitary current in black lipid bilayers. In silico, docking experiments are used to study the molecular details of the binding. We identified the first scorpion venom peptide inhibiting Kv3.1 current at 170 nM. This toxin is the alpha-KTx 15.1, which occludes the Kv3.1 channel pore by means of the lysine 27 lateral chain. This study highlights, for the first time, the modulation of the Kv3.1 by alpha-KTx 15.1, which could be an interesting starting compound for developing therapeutic biomolecules against Kv3.1-associated diseases. 相似文献
66.
Sukhprit Singh Sonia Mahajan Harpal Kaur 《Journal of the American Oil Chemists' Society》1999,76(1):103-107
A tetrahydrofuran ring containing oligoethylene glycol ethers has been synthesized from the seed oil of Vernonia anthelmintica. The seed oil was reacted with mono-, di-, and triethylene glycols in the presence of boron trifluoride etherate, followed
by saponification and esterification (MeOH/H+). The oligoethylene glycol ethers thus obtained were epoxidized with perbenzoic acid. The 9,10-epoxy oligoethylene glycol
ethers so formed were intramolecularly cyclized in dry benzene using boron trifluoride etherate as a catalyst to yield the
tetrahydrofuran ring containing oligoethylene glycol ethers; methyl 9,12-epoxy, 10-hydroxy-13-[2-hydroxyethyl-1-oxy]; methyl
9,12-epoxy,10-hydroxy-13-[2-hydroxy-3-oxapentyl-1-oxy] and methyl 9,12-epoxy,10-hydroxy-13-[8-hydroxy-3,6-dioxaoctyl-1-oxy]octadecanoates,
respectively. 相似文献
67.
Reactions between Strontium-Substituted Lanthanum Manganite and Yttria-Stabilized Zirconia: II, Diffusion Couples 总被引:1,自引:0,他引:1
Kjersti Kleveland Mari-Ann Einarsrud Christian R. Schmidt Senem Shamsili Sonia Faaland Kjell Wiik Tor Grande 《Journal of the American Ceramic Society》1999,82(3):729-734
Formation of secondary phases and diffusion of cations in diffusion couples of yttria-stabilized zirconia and lanthanum manganite substituted with 0 to 60 mol% strontium have been studied by scanning electron microscopy and energy dispersive X-ray spectroscopy. Only the primary phases were observed after 120 h at 1200°C, while formation of secondary phases was identified already after 1 h heat treatment at 1350°C. The phase composition of the reaction layer altered from La2 Zr2 O7 to SrZrO3 at increasing Sr content in La x Sr1- x MnO3 . The thickness of the reaction layer was increasing with heat treatment time. In diffusion couples of La0.4 Sr0.6 MnO3 formation of manganese oxide was observed in the perovskite layer after 1 h heat treatment at 1350°C, while isolated grains of SrZrO3 relatively deep inside the zirconia were observed after longer heat treatment time. Diffusion of Mn into zirconia was observed preferenced along grain boundaries in the early stage of the interface reaction. 相似文献
68.
Luiz F.G. Setz Isabel Santacruz M. Teresa Colomer Sonia R.H. Mello-Castanho Rodrigo Moreno 《Journal of the European Ceramic Society》2010,30(14):2897-2903
Lanthanum chromite (LaCrO3) is currently the most widely studied material as interconnector layers for solid oxide fuel cells (SOFC). The complexity of microstructures and geometries of SOFC devices, which are usually built-up by lamination of the different constitutive layers, make it necessary a precise control of processing parameters to achieve the desired combination of properties. Much effort has been devoted to the processing of electrodes and electrolytes but the other layers, such as that of interconnecting material, have received scarce attention. This work deals with the preparation and optimisation of the rheological behaviour of concentrated suspensions of Sr- and Co-doped LaCrO3 and the subsequent tape casting to produce homogeneous thin sheets to be used in the SOFC stack.The starting powder was produced by combustion synthesis from the corresponding nitrates and urea as a fuel, and had a final composition of La0.80Sr0.20Cr0.92Co0.08O3. These powders were dispersed in ethanol with commercial copolymers (Hypermer, KD6) to solids loading of up to 58 wt%. The binding system (BS) consisted of a mixture of a binder, polyvinyl butyral-co-vinyl alcohol-co-vinyl acetate (PVA-PVAc), and two plasticizers, polyethyleneglycol (PEG400) and benzylbutylphthalate (BBP). The effect of the binding system content and the binder-to-plasticizer ratio on the tape casting performance and the characteristics of the green and the sintered tapes, were studied, as well as the influence of the casting parameters (casting speed and blades height). 相似文献
69.
Michal Kowara Sonia Borodzicz-Jazdzyk Karolina Rybak Maciej Kubik Agnieszka Cudnoch-Jedrzejewska 《International journal of molecular sciences》2021,22(11)
Myocardial infarction is one of the major causes of mortality worldwide and is a main cause of heart failure. This disease appears as a final point of atherosclerotic plaque progression, destabilization, and rupture. As a consequence of cardiomyocytes death during the infarction, the heart undergoes unfavorable cardiac remodeling, which results in its failure. Therefore, therapies aimed to limit the processes of atherosclerotic plaque progression, cardiac damage during the infarction, and subsequent remodeling are urgently warranted. A hopeful therapeutic option for the future medicine is targeting and regulating non-coding RNA (ncRNA), like microRNA, circular RNA (circRNA), or long non-coding RNA (lncRNA). In this review, the approaches targeted at ncRNAs participating in the aforementioned pathophysiological processes involved in myocardial infarction and their outcomes in preclinical studies have been concisely presented. 相似文献
70.