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1.
Lydia Saidi Dr. Djenisa H. A. Rocha Dr. Oualid Talhi Dr. Yamina Bentarzi Prof. Dr. Bellara Nedjar-Kolli Dr. Khaldoun Bachari Dr. Filipe A. Almeida Paz Dr. Luisa A. Helguero Prof. Dr. Artur M. S. Silva 《ChemMedChem》2019,14(10):1041-1048
Breast and prostate cancers are frequently treated with chemotherapy. Several novel chemicals are being reported for this purpose, particularly synthetic and natural benzophenones. This work reports the synthesis of substituted 2-hydroxybenzophenones through 1,4-conjugate addition/intramolecular cycloaddition/dehydration of nitromethane on key intermediate chromones. Structures were extensively studied by means of 2D NMR spectroscopy and single-crystal XRD. Their cytotoxicity was evaluated in vitro in two breast cancer cell lines (MDA-MB-231 and T47-D) and one prostate cancer cell line (PC3). The most potent compound exhibited good cytotoxic effects against the three cancer cell lines (IC50 values ranging from 12.09 to 26.49 μm ) and induced cell-cycle retardation only on prostate cancer cells, which suggested that it might exert cell-type-specific effects. 相似文献
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LM Mendoza P Paz A Zuberi G Christianson D Roopenian N Shastri 《Canadian Metallurgical Quarterly》1997,7(4):461-472
The products of minor histocompatibility (H) loci are serious barriers to tissue transplantation even among major histocompatibility complex (MHC) identical individuals, frequently causing chronic graft rejection and graft versus host disease. Over 50 minor H loci map to mouse autosomal chromosomes but none are known at the molecular level. By expression cloning, we identified the H13 locus, a classical minor H locus first detected 30 years ago by the trait of graft rejection. The H13a allele is located on chromosome 2 and encodes a novel protein that yields the rare naturally processed nonapeptide SSVVGVWYL (SVL9) for presentation by the Db MHC class I molecule. The SVL9 peptide binds Db MHC despite the absence of the consensus binding motif, and a conservative methyl group substitution (Valine 4 <--> Isoleucine) explains why reciprocal T cell responses are elicited in H13a and H13b congenic strains. 相似文献
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The purpose of this study was to examine predictors and consequences of spouses' involvement in each others' strategies for pursuing important personal goals called life tasks. Husbands and wives within 39 short- and long-term marriages described five life tasks and provided appraisals of whether each was shared with their spouse. Participants later completed 14 consecutive diary entries recording daily life task pursuit strategies, the extent of spouse involvement in each, and measures of positive and negative affect. Results indicated that interdependence in life task appraisals prospectively predicted greater spouse involvement, and greater spouse involvement was associated with more positive affect for that day. Life task appraisals may provide avenues for understanding couples' strategies for dealing with goals or stressors and how those strategies affect mood. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Jodi E Williams Susan E. Duncan Robert C. Williams Kumar Mallikarjunan William N. Eigel III Sean F. O'Keefe 《Journal of food science》2006,71(3):S265-S269
ABSTRACT: Flavor characteristics of roasted peanuts over short-term storage were explored through sensory and chemical analyses. The volatiles from freshly roasted peanuts were evaluated over short-time (21 d) storage using gas chromatography, chemosensory techniques, and a sensory panel to quantify and identify pyrazines and hexanal over a 21-d storage period. A significant decrease ( P < 0.05) was noted in 2,3-diethylpyrazine, 2-methoxypyrazine, 2,3-dimethylpyrazine, 2-ethyl-3-methylpyrazine, and 2,3,5-trimethylpyrazine concentrations over a 21-d period. No significant difference ( P > 0.05) was noted in the 2-methylpyrazine and 2-ethylpyrazine concentrations. The hexanal concentration significantly increased ( P < 0.05) over the 21-d period. The peroxide values and sensory analysis agreed with these results. A significant increase ( P < 0.05) in peroxide value was seen at days 14 and 21, and a significant decrease ( P < 0.05) in fresh roasted peanuty flavor from day 0 to 21 and significant increases ( P < 0.05) in painty, cardboardy, and bitter flavors from day 7 to 21 with the sensory analysis. The electronic nose successfully separated day 0 and 21 samples from day 7 and 14 samples, which were also separated but with some overlap. 相似文献
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The aim of this study was to assess whether P-glycoprotein (Pgp) inhibitors altered the blood-brain barrier and enhanced vinblastine (VBL) distribution in brain, testis and other Pgp-expressing tissues. Trifluoperazine, cyclosporin A, amiodarone, quinidine, the nifedipine analog Bay K8644 and verapamil were selected among Pgp inhibitors and were administered intraperitoneally 1 hr before an intravenous dose of 10 mg/kg VBL. Trifluoperazine and cyclosporin A were also administered intraperitoneally for 7 days before VBL. VBL and its metabolite O4-deacetylvinblastine were measured in tissues by high-performance liquid chromatography assay. None of the reversing agents (RA) appreciably raised VBL concentrations in brain and testis, whereas all except quinidine significantly enhanced VBL distribution in liver and kidney; the most effective were trifluoroperazine and cyclosporin A. In mice treated with RA and VBL combined, O4-deacetylvinblastine levels in liver and kidney reached either the same or higher levels than in mice treated with VBL alone, indicating that the increase in VBL levels is not due to inhibition of its metabolism. The main conclusions are that (1) inhibitors of Pgp, even at high doses, do not increase the permeability of the blood-brain barrier in mice, suggesting caution in the clinical use of RA combined with antitumor agents for brain tumors; and (2) several RA achieve high enough concentrations to enhance the distribution of VBL in other normal tissues expressing Pgp, thus potentially increasing VBL toxicity. 相似文献
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Hypothesized that social skills training could improve communications between adolescents and parents while enhancing improvement in perceived communication and problem-solving behaviors. 25 parent–adolescent dyads (all members of the Church of the Latter Day Saints) participated in a pre- and posttest experimental and control group design. The 18 experimental dyads completed a social skills program. Analyses revealed significant training effects on all social skills in the program, but perceived improvement was slightly higher for parents than for adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Lasserre S Hernando J Hill S Schümann F Anasagasti Pde M Jaoudé GA Markram H 《IEEE transactions on visualization and computer graphics》2012,18(2):214-227
We present a process to automatically generate three-dimensional mesh representations of the complex, arborized cell membrane surface of cortical neurons (the principal information processing cells of the brain) from nonuniform morphological measurements. Starting from manually sampled morphological points (3D points and diameters) from neurons in a brain slice preparation, we construct a polygonal mesh representation that realistically represents the continuous membrane surface, closely matching the original experimental data. A mapping between the original morphological points and the newly generated mesh enables simulations of electrophysiolgical activity to be visualized on this new membrane representation. We compare the new mesh representation with the state of the art and present a series of use cases and applications of this technique to visualize simulations of single neurons and networks of multiple neurons. 相似文献