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971.
González-Díaz H Prado-Prado F García-Mera X Alonso N Abeijón P Caamaño O Yáñez M Munteanu CR Pazos A Dea-Ayuela MA Gómez-Muñoz MT Garijo MM Sansano J Ubeira FM 《Journal of proteome research》2011,10(4):1698-1718
Many drugs with very different affinity to a large number of receptors are described. Thus, in this work, we selected drug-target pairs (DTPs/nDTPs) of drugs with high affinity/nonaffinity for different targets. Quantitative structure-activity relationship (QSAR) models become a very useful tool in this context because they substantially reduce time and resource-consuming experiments. Unfortunately, most QSAR models predict activity against only one protein target and/or they have not been implemented on a public Web server yet, freely available online to the scientific community. To solve this problem, we developed a multitarget QSAR (mt-QSAR) classifier combining the MARCH-INSIDE software for the calculation of the structural parameters of drug and target with the linear discriminant analysis (LDA) method in order to seek the best model. The accuracy of the best LDA model was 94.4% (3,859/4,086 cases) for training and 94.9% (1,909/2,012 cases) for the external validation series. In addition, we implemented the model into the Web portal Bio-AIMS as an online server entitled MARCH-INSIDE Nested Drug-Bank Exploration & Screening Tool (MIND-BEST), located at http://miaja.tic.udc.es/Bio-AIMS/MIND-BEST.php . This online tool is based on PHP/HTML/Python and MARCH-INSIDE routines. Finally, we illustrated two practical uses of this server with two different experiments. In experiment 1, we report for the first time a MIND-BEST prediction, synthesis, characterization, and MAO-A and MAO-B pharmacological assay of eight rasagiline derivatives, promising for anti-Parkinson drug design. In experiment 2, we report sampling, parasite culture, sample preparation, 2-DE, MALDI-TOF and -TOF/TOF MS, MASCOT search, 3D structure modeling with LOMETS, and MIND-BEST prediction for different peptides as new protein of the found in the proteome of the bird parasite Trichomonas gallinae, which is promising for antiparasite drug targets discovery. 相似文献
972.
Diabetic retinopathy is a disease of the retinal microvasculature that develops as a complication of diabetes mellitus and constitutes a major cause of blindness in adults of all ages. Diabetic retinopathy is characterized by the loss of capillary cells leading to increased vasopermeability, ischemia, and hypoxia that trigger the excessive formation of new blood vessels in the retina. The influence of the pituitary gland in the pathophysiology of diabetic retinopathy was recognized nearly six decades ago, but the contribution of pituitary hormones to this disease remains unclear. Recent studies have shown that the pituitary hormone prolactin is proteolytically cleaved to vasoinhibins, a family of peptides with potent antivasopermeability, vasoconstrictive, and antiangiogenic actions that can protect the eye against the deleterious effects of the diabetic state. In this review, we summarize what is known about the changes in the circulating levels of prolactin and vasoinhibins during diabetes and diabetic retinopathy as well as the implications of these changes for the development and progression of the disease with particular attention to hyperprolactinemia in pregnancy and postpartum. We discuss the effects of prolactin and vasoinhibins that may impact diabetic retinopathy and suggest these hormones as important targets for therapeutic interventions. 相似文献
973.
974.
Aleida J. Sandoval Doralys Guilarte Jos�� A. Barreiro Elissabetta Lucci Alejandro J. M��ller 《Food biophysics》2011,6(3):424-432
The effectiveness of thymol as an antimicrobial agent during the determination of equilibrium moisture sorption data at high-water
activities (0.50–0.98) was studied at 5, 23, and 45 °C in oat flour. The static gravimetric (SG) method (with and without
added thymol) and the dynamic vapor sorption technique (DVS) were used. Microbial growth in samples conditioned in these environments
at temperatures of 5 and 45 °C was null indicating no need for the use of thymol at these temperatures. However, samples confined
in environments kept at 23 °C, when the SG method was used, needed addition of thymol since mold growth took place in its
absence. The statistical comparison between experimental equilibrium moisture content (EMC) mean values showed that, at 45 °C,
EMC values obtained using the SG technique with added thymol were significantly higher than those obtained without thymol
by both SG and DVS techniques. This could indicate an interaction of thymol with food components or absorption by lipids present.
Therefore, caution must be exerted when using thymol as an antimicrobial agent at elevated temperatures and high equilibrium
relative humidity. Moisture adsorption isotherms for oat flour were determined using a DVS technique and no isotherm crossover
with temperature, as previously reported for this product using thymol as an antimicrobial agent, was exhibited. Moisture
sorption data obtained in this work by DVS can be considered more accurate than those previously reported for oat flour, since
no external agent was involved during isotherm determinations. 相似文献
975.
Norma Espinoza-Herrera Ruth Pedroza-Islas Eduardo San Mart��n-Martinez Alfredo Cruz-Orea Sergio Armando Tom��s 《Food biophysics》2011,6(1):106-114
The proposal in this study was to evaluate the physical properties of different biopolymers films. The materials used were:
pectin, carboxyl methylcellulose, methylcellulose, hydroxyl propylcellulose, hydroxypropyl-methylcellulose, and corn waxy
starch; from these polysaccharides aqueous dispersions were prepared to 3% (w/v) for obtained films. In these biopolymer films, the thermal diffusivities (α) was evaluated by the Open Photoacoustic Cell
method; also, their mechanical properties as tensile strength, elongation, and Young’s modulus were measured, their crystallinity
percentage was evaluated by X-ray diffraction and microstructure through atomic force microscopy in contact mode. From the
polysaccharide films, it was observed that most of them were flexible and transparent. In the case of the films, mechanical
properties were found that the highest value of tensile strength and Young’s modulus corresponded to carboxyl methylcellulose
with 69.17 and 1,912.20 MPa values, respectively. Also, Open Photoacoustic Cell method and X-ray diffraction measurements
showed that there exist a correlation between the thermal diffusivity values and the crystallinity measured in the biopolymer
films. It was also observed that α values of cellulose derived was affected by the substitution group in the molecule, reaching
the highest α value, the films of carboxyl methylcellulose. Regarding the microstructural of the films, starch showed the
highest roughness value (88.6 nm) whereas hydroxypropyl-methylcellulose resulted with the lowest roughness value (7.67 nm). 相似文献
976.
Tomàs Pinós Mario Marotta Eduard Gallardo Isabel Illa Jorge Díaz-Manera Emiliano Gonzalez-Vioque Elena García-Arumí Antoni L. Andreu Ramon Martí 《Mitochondrion》2011,11(1):228-233
We report a heteroplasmic novel mutation m.5636T>C in the mt-tRNAAla in a patient with bilateral ptosis and ophthalmoparesis in whom a muscle biopsy showed cytochrome c oxdidase (COX) negative and ragged red fibers. Using laser capture microdissection we have isolated COX negative fibers and COX positive fibers from the muscle of the patient and determined that the mutation load was clearly increased in COX negative muscle fibers. Additionally, the mutated m.5636T nucleotide is conserved in all the mammal and non-mammal species analyzed and might be structurally relevant as it is located in a position involved in the formation of tertiary structure of canonical mitochondrial tRNAs. 相似文献
977.
978.
Negredo A Palacios G Vázquez-Morón S González F Dopazo H Molero F Juste J Quetglas J Savji N de la Cruz Martínez M Herrera JE Pizarro M Hutchison SK Echevarría JE Lipkin WI Tenorio A 《PLoS pathogens》2011,7(10):e1002304
Filoviruses, amongst the most lethal of primate pathogens, have only been reported as natural infections in sub-Saharan Africa and the Philippines. Infections of bats with the ebolaviruses and marburgviruses do not appear to be associated with disease. Here we report identification in dead insectivorous bats of a genetically distinct filovirus, provisionally named Lloviu virus, after the site of detection, Cueva del Lloviu, in Spain. 相似文献
979.