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排序方式: 共有249条查询结果,搜索用时 15 毫秒
51.
Rocío Quiroga Esther Nistal Brisamar Estbanez David Porras María Jurez-Fernndez Susana Martínez-Flrez María Victoria García-Mediavilla Jos A. de Paz Javier Gonzlez-Gallego Sonia Snchez-Campos María J. Cuevas 《Experimental & molecular medicine》2020,52(7):1048
Childhood obesity has reached epidemic levels and is a serious health concern associated with metabolic syndrome, nonalcoholic fatty liver disease, and gut microbiota alterations. Physical exercise is known to counteract obesity progression and modulate the gut microbiota composition. This study aims to determine the effect of a 12-week strength and endurance combined training program on gut microbiota and inflammation in obese pediatric patients. Thirty-nine obese children were assigned randomly to the control or training group. Anthropometric and biochemical parameters, muscular strength, and inflammatory signaling pathways in mononuclear cells were evaluated. Bacterial composition and functionality were determined by massive sequencing and metabolomic analysis. Exercise reduced plasma glucose levels and increased dynamic strength in the upper and lower extremities compared with the obese control group. Metagenomic analysis revealed a bacterial composition associated with obesity, showing changes at the phylum, class, and genus levels. Exercise counteracted this profile, significantly reducing the Proteobacteria phylum and Gammaproteobacteria class. Moreover, physical activity tended to increase some genera, such as Blautia, Dialister, and Roseburia, leading to a microbiota profile similar to that of healthy children. Metabolomic analysis revealed changes in short-chain fatty acids, branched-chain amino acids, and several sugars in response to exercise, in correlation with a specific microbiota profile. Finally, the training protocol significantly inhibited the activation of the obesity-associated NLRP3 signaling pathway. Our data suggest the existence of an obesity-related deleterious microbiota profile that is positively modified by physical activity intervention. Exercise training could be considered an efficient nonpharmacological therapy, reducing inflammatory signaling pathways induced by obesity in children via microbiota modulation.Subject terms: High-throughput screening, DNA metabolism 相似文献
52.
John N. Low Justo Cobo Manuel Nogueras Adolfo Snchez Harlen Torres Braulio Insuasty 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(5):o298-o300
The supramolecular structure of the title compound, C19H15N3, is defined by π–π‐stacking and C—H?π interactions. There are no conventional hydrogen bonds in the structure. 相似文献
53.
John Nicolson Low Justo Cobo Manuel Nogueras Adolfo Snchez Braulio Insuasty Harlen Torres 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):o39-o41
2,2‐Dimethyl‐5‐[3‐(4‐methylphenyl)‐2‐propenylidene]‐1,3‐dioxane‐4,6‐dione, C16H16O4, crystallizes in the triclinic space group , with two molecules in the asymmetric unit. These molecules and a centrosymmetrically related pair, linked together by weak C—H?O hydrogen bonds, form a tetramer. 5‐[3‐(4‐Chlorophenyl)‐2‐propenylidene]‐2,2‐dimethyl‐1,3‐dioxane‐4,6‐dione, C15H13ClO4, also crystallizes in the triclinic space group , with one molecule in the asymmetric unit. Centrosymmetrically related molecules are linked together by weak C—H?O hydrogen bonds to form dimers which are further linked by yet another pair of centrosymmetrically related C—H?O hydrogen bonds to form a tube which runs parallel to the a axis. 相似文献
54.
Jairo Quiroga Diana Mejía Braulio Insuasty Rodrigo Abonía Manuel Nogueras Adolfo Snchez Justo Cobo J. N. Low 《Journal of heterocyclic chemistry》2002,39(1):51-54
Reaction of 3‐formylchromone ( 1 ) with 5‐amino‐1H‐pyrazoles ( 2 ) in ethanol, afforded 6‐(2‐hydroxy‐benzoyl)pyrazolo[1,5‐a]pyrimidines ( 3a‐g ) in good yields. The structures and the regiospecificity of the reaction were established by nmr measurements and X‐ray analysis, in which soft intermolecular hydrogen‐bonded networks were found. 相似文献
55.
Jairo Quiroga Angelina Hormaza Braulio Insuasty Manuel Mrquez 《Journal of heterocyclic chemistry》1998,35(2):409-412
A series of dihydropyrazolo[3,4-b]pyridin-6-ones 3 was prepared by cyclization of 5-amino-1-aryl-3-methylpyrazoles 1 and Meldrum's acid benzylidene derivatives 2 in nitrobenzene. The structure of 4,5-dihydropyrazolo[3,4-b]pyridin-6-ones and reaction orientation were determined by nmr measurements. 相似文献
56.
We report ab initio computations with the Vienna Ab initio Simulation Package (VASP) aimed at elucidating the adsorption mechanism of graphene-like structures on (111) Pd, Pt, and Ni surfaces. To study the adsorption properties, we simulate an already-formed graphene layer. We present a comparative discussion of the graphene interactions with the three metals, focusing on the very particular adsorption of graphene over Pd. 相似文献
57.
Roberto C. Gallo‐Villanueva Victor H. Perez‐Gonzalez Braulio Cardenas‐Benitez Binny Jind Sergio O. Martinez‐Chapa Blanca H. Lapizco‐Encinas 《Electrophoresis》2019,40(10):1408-1416
Insulator‐based dielectrophoresis (iDEP) is the electrokinetic migration of polarized particles when subjected to a non‐uniform electric field generated by the inclusion of insulating structures between two remote electrodes. Electrode spacing is considerable in iDEP systems when compared to electrode‐based DEP systems, therefore, iDEP systems require high voltages to achieve efficient particle manipulation. A consequence of this is the temperature increase within the channel due to Joule heating effects, which, in some cases, can be detrimental when manipulating biological samples. This work presents an experimental and modeling study on the increase in temperature inside iDEP devices. For this, we studied seven distinct channel designs that mainly differ from each other in their post array characteristics: post shape, post size and spacing between posts. Experimental results obtained using a custom‐built copper Resistance Temperature Detector, based on resistance changes, show that the influence of the insulators produces a difference in temperature rise of approximately 4°C between the designs studied. Furthermore, a 3D COMSOL model is also introduced to evaluate heat generation and dissipation, which is in good agreement with the experiments. The model allowed relating the difference in average temperature for the geometries under study to the electric resistance posed by the post array in each design. 相似文献
58.
Simultaneous quantitation of meperidine,normeperidine, tramadol,propoxyphene and norpropoxyphene in human plasma using solid‐phase extraction and gas chromatography/mass spectrometry: Method validation and application to cardiovascular safety of therapeutic doses 下载免费PDF全文
59.
Huxley M Sanchez-Cano C Browning MJ Navarro-Ranninger C Quiroga AG Rodger A Hannon MJ 《Dalton transactions (Cambridge, England : 2003)》2010,39(47):11353-11364
A range of androgen conjugates with non-conventional platinum(II) complexes have been synthesised with the aim of targeting tumour cells since many display elevated levels of the androgen receptor. The androgenic platinum conjugates are delivered into selected cells with improved efficiency (when compared to their non-steroidal analogues). The act of conjugating an androgen to a platinum(II) complex resulted in synergistic effects between the metallic centre and the steroidal ligand, creating highly potent platinum(II) complexes from the inactive components. 相似文献
60.
We demonstrate a method to directly demodulate closed-fringe interferograms using a kind of active contour called a snake. This method can be used to demodulate a single closed-fringe interferogram when its background illumination and/or contrast terms have a spatial frequency similar to the spatial frequency of the equivalent normalized interferogram. Among other cases, this problematic usually appears in interferometry when spurious reflection appears in the interferogram. In these situations, typical Fourier-based methods are of no help. We show a set of simulations and experimental results that prove the effectiveness of the proposed method. 相似文献