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651.
652.
A number of polymeric iron(III) oxidised glutathione materials have been prepared. Mössbauer spectroscopic, magnetic susceptibility data and electronic reflectance spectra studies on these iron(III) materials are discussed.Two stoichiometries 1:1 and 1:2 have been established for iron(II)-glutathione materials. Spectroscopic studies show that the 1:1 materials contain high spin iron(II) in distorted five and six coordinated environments, whereas the 1:2 materials contain only distorted six-coordinated high spin iron(II). The nature of the coordinating ligands are discussed.  相似文献   
653.
β-Amyloid peptide (Aβ) is believed to play a recognized role in pathogenesis of Alzheimer's disease (AD). Self-association of Aβ peptide into amyloid fibrils causes neurotoxicity. Compounds capable of interfering with Aβ–Aβ interaction through binding to nucleation sites can inhibit Aβ amyloidogenesis and Aβ-induced cytotoxicity. AA3E2 is a triazine-derivative whose anti-amyloidogenic ability has previously been established. In the present study, we evaluated the protective effect of AA3E3 against Aβ1–42-induced toxicity in SK-N-MC cell line. The cell exposure to the co-incubated Aβ1–42 with AA3E2 decreased the cell viability loss dose-dependently, compared to cells exposed to Aβ1–42 fibrils.Co-incubation with AA3E2 also attenuated the ROS production, activation of caspase-3 and the extent of apoptotic cell death induced by Aβ1–42 fibril. Moreover, the 3D structure of the molecular associates between Aβ1–42 and AA3E2 were theoretically determined by docking studies. Our docking data indicated that AA3E2 inhibits the formation of Aβ fibril likely via binding to the nucleation site within the hydrophobic region of Aβ (KLVFF). These observations provide the background for future design of more elegant β-breaking agents for dissolution of Aβ fibrillar aggregates.  相似文献   
654.
Abstract

Growth and production of carotenoid in three Dunaliella species (Dunaliella salina (Dunal) Teodoresco, Dunaliella bardawil Ben-Amotz & Avron and Dunaliella sp.) were investigated using flat-plate photobioreactors in outdoor conditions with two optical paths (3?cm and 5?cm). The experiment was conducted in duplicate and lasted four weeks during which light intensity, temperature, pH and optical density were checked daily. The pigment production (total carotenoid and chlorophyll a) was monitored every two days. To induce an additional stress besides temperature and light intensity, two different salt concentrations were used, i.e. 6% and 8% NaCl. The highest growth in all treatment groups was noticed for Dunaliella sp. followed by D. bardawil and D. salina. D. salina produced a higher content of carotenoid concentrations corresponding to 5?cm/8% and 5?cm/6% groups; 779.102?±?0.434?μg.mL?1 and 694.326?±?0.098?μg.mL?1 were registered at the end of the experiment. The same species had also greater content of β-carotene.  相似文献   
655.

Traumatic brain injury (TBI) is known as an acute degenerative pathology of the central nervous system, and has been shown to increase brain aquaporin 4 (AQP4) expression. Various molecular mechanisms affect AQP4 expression, including neuronal high mobility group box 1, forkhead box O3a, vascular endothelial growth factor, hypoxia-inducible factor-1 α (HIF-1 α) sirtuin 2, NF-κB, Malat1, nerve growth factor and Angiotensin II receptor type 1. In addition, inhibition of AQP4 with FK-506, MK-801 (indirectly by targeting N-methyl-d-aspartate receptor), inactivation of adenosine A2A receptor, levetiracetam, adjudin, progesterone, estrogen, V1aR inhibitor, hypertonic saline, erythropoietin, poloxamer 188, brilliant blue G, HIF-1alpha inhibitor, normobaric oxygen therapy, astaxanthin, epigallocatechin-3-gallate, sesamin, thaliporphine, magnesium, prebiotic fiber, resveratrol and omega-3, as well as AQP4 gene silencing lead to reduced edema upon TBI. This review summarizes current knowledge and evidence on the relationship between AQP4 and TBI, and the potential mechanisms involved.

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656.
A bryozoan fauna containing seven species is described from the Upper Frasnian (Upper Devonian) rocks in the Khoshyeilagh Section, Alborz Mountains (northern Iran). The studied bryozoan assemblage includes one new trepostome species, Eridotrypella alborzensis sp. nov., an additional four species identified at species level: two trepostomes, Minussina akkayaensis Volkova, 1974 and Leptotrypella inaudita Morozova, 1961, and two rhabdomesine cryptostomes, Bigeyella mariae (Morozova, 1961) and Saffordotaxis multispinata (Morozova, 1955). Furthermore, two species are described in open nomenclature: the trepostome Schulgina sp. and the rhabdomesine cryptostome Nicklesopora sp. The studied fauna shows a close similarity at the species level between northern Iran and the Altai-Sayan Folded Belt (Russia), south China, and Transcaucasia.  相似文献   
657.
658.
The light-induced changes of plasmalemma potential and of chlorophyllfluorescence were compared with changes induced by the modulationof O2- or CO2-concentration. The fast depolarisation of plasmalemmapotential upon illumination as labeled by the time-constant  相似文献   
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