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81.
Starting from our previously reported hit, a series of 1,5-diaryl-1,2,3-triazole-4-carbohydrazones were synthesized and evaluated as inhibitors of the YAP/TAZ-TEAD complex. Their binding to hTEAD2 was confirmed by nanodifferential scanning fluorimetry, and some of the compounds were also found to moderately disrupt the YAP-TEAD interaction, as assessed by a fluorescence polarization assay. A TEAD luciferase gene reporter assay performed in HEK293T cells and RTqPCR measurements in MDA-MB231 cells showed that these compounds inhibit YAP/TAZ-TEAD activity to cells in the micromolar range. In spite of the cytotoxic effects displayed by some of the compounds of this series, they are still good starting points and can be suitably modified into an effective and viable YAP-TEAD disruptor in the future.  相似文献   
82.
Bone microarchitecture has been shown to provide useful information regarding the evaluation of skeleton quality with an added value to areal bone mineral density, which can be used for the diagnosis of several bone diseases. Bone mineral density estimated from dual-energy X-ray absorptiometry (DXA) has shown to be a limited tool to identify patients’ risk stratification and therapy delivery. Magnetic resonance imaging (MRI) has been proposed as another technique to assess bone quality and fracture risk by evaluating the bone structure and microarchitecture. To date, MRI is the only completely non-invasive and non-ionizing imaging modality that can assess both cortical and trabecular bone in vivo. In this review article, we reported a survey regarding the clinically relevant information MRI could provide for the assessment of the inner trabecular morphology of different bone segments. The last section will be devoted to the upcoming MRI applications (MR spectroscopy and chemical shift encoding MRI, solid state MRI and quantitative susceptibility mapping), which could provide additional biomarkers for the assessment of bone microarchitecture.  相似文献   
83.
The glial-derived calcium-binding protein S100B can be secreted to act as a neurotrophic factor or a mitogen, stimulating proliferation of glial cells. The extracellular S100B activities rely on the oxidation of the protein cysteine residues (Kligman, D., and Marshak, D. R. (1985) Proc. Natl. Acad. Sci. U. S. A. 82, 7136-7139; Winningham-Major, F., Staecker, J. L., Barger, S. W., Coats, S., and Van Eldik, L. J. (1989) J. Cell Biol. 109, 3063-3071). Here we show that oxidation of the S100B cysteine residues, Cys-68 and Cys-84, induces a conformational change in the protein structure, unmasking a canonical CKII phosphorylation site located within the typical EF-hand calcium-binding site IIbeta. Intrasubunit disulfide-bridged S100B monomer and disulfide-bonded S100B dimer are phosphorylated by the catalytic CKII-alpha subunit on Ser-62 with a Km of 0.5 microM and a Vmax of 10 pmol/min/100 pmol of S100B. Oxidized S100B is the best in vitro CKII-alpha substrate identified so far. Next we show that intrasubunit disulfide-bridged S100B monomer is the most potent S100B species to stimulate [3H]thymidine uptake by C6 glial cells in culture. In addition, the phosphorylated intrasubunit disulfide-bridged S100B monomer retains apparent mitogenic activity toward C6 glial cells, and hence, 32P-labeled S100B should be a useful probe for characterizing the mechanisms by which extracellular oxidized S100B functions. Finally, we show that formation of intrasubunit disulfide-bridged S100B monomer is stimulated by peroxynitrite anion, suggesting that production of mitogenic S100B species could be enhanced in neuropathology associated with peroxynitrite anion production.  相似文献   
84.
The influence of five strains of lactic acid bacteria (four Lactobacillus and one Carnobacterium) on the quality of fermented salmon fillets was studied. Best starter growth (increase of more than 1 log in 3 days) and acidification of muscle (e.g. pH reduction of approximately 0.7 units in 5 days) were achieved with the two commercial strains L. sake LAD and L. alimentarius BJ33. pH reduction was consistently lower (e.g. reduction of 0.2 units in 5 days) with C. piscicola 85. Protein breakdown as observed on SDS-PAGE gels was similar for all strains. In contrast, the starter strain did influence texture and colour changes. Fast acidifying strains L. sake LAD and L. alimentarius BJ33 brought about a firmer overall texture and a lighter colour, while softening of flesh occurred in samples processed with C. piscicola 85. Sensory evaluations indicated that samples processed with fast acidifying strains were preferred. L. sake LAD and L. alimentarius BJ33 are regarded as suitable starters for fermentation of salmon fillets.  相似文献   
85.
An interface is presented that uses time compression to allow static TV pictures (picked up by standard videoprocessing systems or synthesized by software) to be displayed at a rate of about 500 frames/s. Time compression of the video signal is achieved in two steps. The digitized video information is first loaded into the memory buffer or the device, the video memory. After completing a computer-aided loading cycle, the device is switched to the automatic reading mode, in which the video memory is read sequentially at a rate of 8 million words/s. Since the format of the picture is 128×128 pixels, the time compression factor, as compared to standard video signals, is about ten. The values of the device parameters (repetition rate, format, and gray tones number) were chosen to meet the requirements of a specific application in the field of vision research: the presentation of complex figures with high information content as stabilized images or, more generally, in the variable retinal feedback condition  相似文献   
86.
Studied the influence of various cognitive modalities on risk assessment. Human Ss: 78 normal male and female French adults (university students). Ss were presented with information related to a potential environmental danger and asked to evaluate the degree of risk. The information involved 3 categories of data presented under 3 experimental conditions: representativeness, availability, and anchoring of the relevant information. A control condition offering no information on which to base the risk assessment was also included. Subjective evaluations of the degree of risk served as the dependent variable. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
The response of normal and transformed rat hepatocytes to oxidative stress was investigated. Isolated normal rat hepatocytes and differentiated hepatoma cells (the Fao cell line was derived from the Reuber H 35 rat hepatoma) in suspension were incubated with the ADP/Fe3+ chelate for 30 min at 37°C. Membrane lipid oxidation was assessed by measuring (i) free malondialdehyde (MDA) production by a high-performance liquid chromatography (HPLC) procedure, (ii) membrane fatty acid disappearance as judged by capillary gas chromatography, and (iii) α-tocopherol oxidation as determined by HPLC and electrochemical detection. The addition of iron led to increased MDA production in normal as well as in transformed cells, and to simultaneous consumption of polyunsaturated fatty acids (PUFA) and α-tocopherol. In addition, in Fao cells more α-tocopherol was consumed during lipid peroxidation while less PUFA was oxidized. Lipid peroxidation was lower in tumoral hepatocytes than in normal cells. This could be due to a difference in membrane lipid composition because of a lower PUFA content and a higher α-tocopherol level in Fao cells. During oxidation, Fao cells produced 1.5 to 2 times less MDA than normal cells, while in the tumoral cells the amount of oxidized PUFA having 3 or more double bonds was 7 to 8 times lower. Therefore, measuring MDA alone as an index of lipid peroxidation did not allow for proper comparison of the membrane lipid oxidizability of transformed cellsvs. the membrane lipid oxidizability of normal cells.  相似文献   
88.
A 24-hr pretreatment of cultured human fibroblasts with trifluoperazine induced a marked increase in incorporation of saturated (stearic, palmitic) and unsaturated (oleic, arachidonic) fatty acids into phospholipids (1.5- to 2-fold for 5.10−5 M trifluoperazine). Concomitantly, incorporation into cholesteryl esters was strongly inhibited (20% of control for 5.10−5 M trifluoperazine). The drug did not change the phospholipid composition of treated cells. The effect of trifluoperazine on oleic acid incorporation into phospholipids was time-dependent and reached a maximum after a six-hr preincubation with the drug. Trifluoperazine also induced an increase in the rate of chase of oleic acid from the different phospholipid classes. In vitro preincubation of cell-free extracts with trifluoperazine resulted in activation of phospholipid acyltransferases, whereas cholesterol acyltransferase activity was decreased. The rapid effect of trifluoperazine together with its effect on a cell-free system suggests a direct action of this amphiphilic drug on the acyltransferase activities, probably by modification of the structural organization of cellular membranes.  相似文献   
89.
Orange and lemon peels were extruded under controlled conditions of varying severity, and their physico-chemical characteristics and effect on the enzymatic hydrolysis of starch and glucose diffusion were studied. Extrusion-cooking treatment increased the soluble fraction of dietary fibre as well as solubilised pectic substances and arabino-galactomannan chains. The apparent viscosities of aqueous extracts of extruded fibre were increased slightly for orange and more markedly for lemon fibre. With both fibre sources, viscosities values were higher in Tris-maleate buffer (0.1 M) than in NaCl (154 mM). However, these modifications had no effect on starch hydrolysis and glucose diffusion in vitro.  相似文献   
90.
Processing solvent additives in polymer:fullerene bulk heterojunction systems are known as a promising method to enhance photovoltaic performance. It is generally agreed that solvent additives enable polymers to have a high degree of molecular order which increases the device performance. However, the understanding of the efficiency enhancement is not complete. There is a lack of insight regarding the quantitative determination of the molecular miscibility between polymer and fullerene as well as the inner morphology changes induced by the additives. In this work, understanding of the influence of the solvent additive 1,8‐octanedithiol (ODT) is provided on the classic system poly(3‐hexylthiophene‐2,5‐diyl):[6,6]‐phenyl‐C61 butyric acid methyl ester (P3HT:PCBM) films. The impact on polymer crystallinity, surface structure, inner morphology, and quantitative molecular miscibility of P3HT and PCBM is studied as a function of ODT volume concentration. The crystallinity is probed with absorption spectroscopy and grazing incidence wide‐angle X‐ray scattering. The morphology and miscibility are characterized via atomic force microscopy and time‐of‐flight grazing incidence small angle neutron scattering. Besides an increased crystallinity and prominent phase separation, ODT increases the solubility of PCBM in P3HT and reduces the size of amorphous P3HT domains. Moreover, solvent processing with a high ODT concentration alters the vertical material composition of the active layer.  相似文献   
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