563 research outputs found
Structure-activity relationships based on 3D-QSAR CoMFA/CoMSIA and design of aryloxypropanol-amine agonists with selectivity for the human β3-adrenergic receptor and anti-obesity and anti-diabetic profiles
Indexación: Scopus.Acknowledgments: This work was supported by FONDECYT No. 11130701. We would also like to thank fDoTr CthLeafbr efeora vthaeil afrbeilei tayvoafiltahbeilsitoyf towfa trheer seoqfutwireadret orecqaulciureladt etothcealAcuDla(thet ttph:e/ A/dDt c(lhatbt.pw:/e/dbstc.cloabm.w/seobfst.wcoamre/-stoofotlws aarned-tools and http://teqip.jdvu.ac.in/QSAR_Tools/). SDG. Conflicts of Interest: The authors declare no conflict of interest. Conflicts of Interest: The authors declare no conflict of interest.The wide tissue distribution of the adrenergic β3 receptor makes it a potential target for the treatment of multiple pathologies such as diabetes, obesity, depression, overactive bladder (OAB), and cancer. Currently, there is only one drug on the market, mirabegron, approved for the treatment of OAB. In the present study, we have carried out an extensive structure-activity relationship analysis of a series of 41 aryloxypropanolamine compounds based on three-dimensional quantitative structure-activity relationship (3D-QSAR) techniques. This is the first combined comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA) study in a series of selective aryloxypropanolamines displaying anti-diabetes and anti-obesity pharmacological profiles. The best CoMFA and CoMSIA models presented values of r2 ncv = 0.993 and 0.984 and values of r2 test = 0.865 and 0.918, respectively. The results obtained were subjected to extensive external validation (q2, r2, r2 m, etc.) and a final series of compounds was designed and their biological activity was predicted (best pEC50 = 8.561). © 2018 by the authors.https://www.mdpi.com/1420-3049/23/5/119
Codariocalyx Gyroides- A New Forage Option for the Humid Tropics
The Southeast Asian shrub legume, Codariocalyx gyroides is adapted to acid, low-fertility soils with poor drainage. Data from 19 RIEPT (International Network for Evaluation of Tropical Pastures) trial sites conducted in the American humid and subhumid tropics were used to define the range of adaptation of C. gyroides. The results show that C. gyroides performs better under high rainfall conditions of the humid tropics with hardly any dry season, and it responds to soil fertility (Ca, P). Future research needs are identified. The release of a commercial cultivar in Colombia is being prepared
A New Kind of Quinonic-Antibiotic Useful Against Multidrug-Resistant S. aureus and E. faecium Infections
Indexación: Scopus.A rapid emergence of resistant bacteria is occurring worldwide, endangering the efficacy of antibiotics and reducing the therapeutic arsenal available for treatment of infectious diseases. In the present study, we developed a new class of compounds with antibacterial activity obtained by a simple, two step synthesis and screened the products for in vitro antibacterial activity against ATCC® strains using the broth microdilution method. The compounds exhibited minimum inhibitory concentrations (MIC) of 1⁻32 μg/mL against Gram-positive ATCC® strains. The structure⁻activity relationship indicated that the thiophenol ring is essential for antibacterial activity and the substituents on the thiophenol ring module, for antibacterial activity. The most promising compounds detected by screening were tested against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VREF) clinical isolates. We found remarkable activity against VREF for compounds 7 and 16, were the MIC50/90 were 2/4 µg/mL and 4/4 µg/mL, respectively, while for vancomycin the MIC50/90 was 256/512 µg/mL. Neither compound affected cell viability in any of the mammalian cell lines at any of the concentrations tested. These in vitro data show that compounds 7 and 16 have an interesting potential to be developed as new antibacterial drugs against infections caused by VREF.https://www.mdpi.com/1420-3049/23/7/177
Fricke and polymer gel 2D dosimetry validation using Monte Carlo simulation
Complexity in modern radiotherapy treatments demands advanced dosimetry systems for quality control. These systems must have several characteristics, such as high spatial resolution, tissue equivalence, three-dimensional resolution, and dose-integrating capabilities. In this scenario, gel dosimetry has proved to be a very promising option for quality assurance. In this study, the feasibility of Fricke and polymer gel dosimeters suitably shaped in form of thin layers and optically analyzed by visible light transmission imaging has been investigated for quality assurance in external radiotherapy. Dosimeter irradiation was carried out with a 6-MV photon beam (CLINAC 600C). The analysis of the irradiated dosimeters was done using two-dimensional optical transmission images. These dosimeters were compared with a treatment plan system using Monte Carlo simulations as a reference by means of a gamma test with parameters of 1 mm and 2%. Results show very good agreement between the different dosimetric systems: in the worst-case scenario, 98% of the analyzed points meet the test quality requirements. Therefore, gel dosimetry may be considered as a potential tool for the validation of other dosimetric systems.Fil: Vedelago, José Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Chacón Obando, D.. Universidad Nacional. Physics Department; Costa Rica. Universidad Nacional de Córdoba; ArgentinaFil: Malano, Francisco Mauricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Conejeros, R.. Servicio de Radioterapia, Icos. Temuco, Chile;Fil: Figueroa, R.. Universidad de la Frontera; ChileFil: Garcia, D.. Servicio de Imagenes por Resonancia Magnética; ChileFil: González, G.. Servicio de Imagenes por Resonancia Magnética; ChileFil: Romero, Marcelo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Santibañez, M.. Servicio de Imagenes por Resonancia Magnética; ChileFil: Strumia, Miriam Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Velásquez, J.. Servicio de Radioterapia; ChileFil: Mattea, Facundo. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Valente, M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad de La Frontera. Departamento de Ciencias Físicas; Chil
Analyzing the turbulent planetary boundary layer by remote sensing systems: the Doppler wind lidar, aerosol elastic lidar and microwave radiometer
he planetary boundary layer (PBL) is the lowermost
region of troposphere and is endowed with turbulent
characteristics, which can have mechanical and/or thermodynamic
origins. This behavior gives this layer great importance,
mainly in studies about pollutant dispersion and
weather forecasting. However, the instruments usually applied
in studies of turbulence in the PBL have limitations
in spatial resolution (anemometer towers) or temporal resolution
(instrumentation aboard an aircraft). Ground-based
remote sensing, both active and passive, offers an alternative
for studying the PBL. In this study we show the capabilities
of combining different remote sensing systems (microwave
radiometer – MWR, Doppler lidar – DL – and elastic lidar
– EL) for retrieving a detailed picture on the PBL turbulent
features. The statistical moments of the high frequency distributions
of the vertical wind velocity, derived from DL,
and of the backscattered coefficient, derived from EL, are
corrected by two methodologies, namely first lag correction
and -2=3 law correction. The corrected profiles, obtained
from DL data, present small differences when compared with
the uncorrected profiles, showing the low influence of noise
and the viability of the proposed methodology. Concerning
EL, in addition to analyzing the influence of noise, we explore
the use of different wavelengths that usually include
EL systems operated in extended networks, like the European
Aerosol Research Lidar Network (EARLINET),This work was supported by the Andalusia
Regional Government through project P12-RNM-2409 and by the
Spanish Agencia Estatal de Investigación (AEI) through projects
CGL2016-81092-R and CGL2017-90884-REDT. We acknowledge
the financial support by the European Union’s Horizon 2020
research and innovation program through project ACTRIS-2 (grant
agreement no. 654109)
Utilización de un método in vitro para evaluar la toxicidad de chaya, una planta nutritiva utilizada en medicina tradicional para la disminución del colesterol.
La “chaya” (Cnidoscolus chayamansa y Cnidoscolus aconitifolius) pertenece a la familia de las Euphorbiacea, es conocida como árbol de espinaca y ha sido cultivada desde la época prehispánica, se usaba como hasta hoy como planta comestible, medicinal y ornamental por más de 10 grupos Mayas y también por otros grupos Mexicanos y Mesoamericanos. Normalmente se encuentra cultivada en huertos familiares o jardines, la hoja algunas veces el pecíolo y los brotes son cosechadas y cocidas para varios tipos de guisados siendo una fuente importante de proteínas, beta caroteno, vitaminas, ácido ascórbico, calcio y hierro o son utilizadas con fines medicinales destacando su propiedad como hipocolesterolémico. El propósito del presente trabajo fue la evaluación preliminar de la toxicidad de tres extractos obtenidos de las hojas de C. chayamansa en un modelo in vitro, utilizando Artemia salina
Índice de saponificación de cinco mantecas determinado mendiante un micrométodo
Las mantecas son triglicéridos sólidos a temperatura ambiente con un notable valor nutritivo por su alto valor calórico y son ampliamente usadas en el procesado de los alimentos. Su calidad puede sufrir deterioros durante el proceso de preparación o en el almacenamiento, por lo que se han establecido parámetros analíticos como el Índice de saponificación para el monitoreo de la calidad. En esta investigación se determinó el Índice de saponificación (IS) de cinco mantecas mediante el empleo de un micrométodo, basado en la Norma Mexicana NMX-F-174-S-1981, para indagar si cumplen con este parámetro de calidad. Las muestras analizadas exhibieron valores que se ubicaron dentro de los rangos de normatividad establecidos en la legislación. La técnica aplicada es una adaptación a nivel microescala y presenta diferencias con la técnica oficial, que le proporcionan una mayor exactitud. Este estudio resalta la importancia de incorporar micrométodos en el diseño de las normas oficiales de análisis dado sus ventajas como rapidez, precisión, exactitud, bajo costo y ser amigable con el medio ambiente
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