678 research outputs found

    Metabolomics as a Tool in Agriculture

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    Metabolomics is a study through can be obtain a better understanding of the complexity of the biological systems, through the chemical composition and relations with the physiology of the plant. The literature describes a lot of information on this support in areas of medicinal plants, chemosystematics, adulteration of plants, etc., but it is scarce in agriculture. At present, agriculture plays a crucial role in human beings. The demand of foods has increased due to the continuous increase in the population, and this requires an increase in the production of crops, besides the crops being affected by the climatic change, attack of pest and diseases and resistance to a conventional agrochemicals. At present, scientists are doing some practices or studies of genetic improvement of crops to increase their production and avoid the problems pointed out. It is an important part of the genomic studies; the results could be the basis for a genetic improvement based on the chemical composition of the crops, and in the metabolomics studies represent a crucial role in their quality for human consumption. The aim of the chapter is to review the literature from 10 years behind emphasizing the importance of metabolomics in crops of economic and feed value

    Aromatic and Medicinal Plants in Mexico

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    Medicinal and aromatic plants in Mexico have been studied and explored through history. Day by day there is an increase in ethnobotanical, taxonomic, or phytochemical studies, providing an encouraging picture of research in Mexico and to support its use in traditional medicine. Chemical and biological exploration permit to provide solutions to the treatment of diseases. With this background, the objective of this chapter is to show the potential of endemic medicinal and aromatic plants in Mexico

    Aislamiento e identificación de volátiles de Physalis philadelphica LAM

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    El objetivo de este trabajo fue aislar e identificar los componentes volátiles del tomate de cáscara Physalis philadelphica Lam. Por lavado con hexano, aireación dinámica (AD) y micro extracción en fase sólida (MEFS) se aislaron volátiles de P. philadelphica, los cuales se analizaron e identificaron por cromatografía de gases (CG) y CG acoplada a espectrometría de masas (CG-EM). Los compuestos recolectados por AD y MEFS se identificaron como salicilato de metilo, β-cariofileno, β-pineno, alcohol bencílico, 3-careno, β-elemeno, decanal y germacreno D. Los componentes recolectados lavando las plantas con hexano fueron β-cariofileno, linolenato de etilo, salicilato de metilo, β-pineno, ácido hexadecanoico, linolenato de metilo, alcohol bencílico, germacreno D, 3-careno, β-elemeno y decanal

    Germinación diferencial asociada con viviparidad facultativa en Stenocereus thurberi (Cactaceae): correlaciones climáticas en poblaciones marginales de Sinaloa, México

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    Background and Aims: Precocious (viviparous) seed germination in fruits of Stenocereus thurberi has been correlated with higher germination rate of the remaining seeds. This study compares the germination of five populations from Sinaloa, Mexico, to determine: 1) whether there is a pattern associated with precocious seed germination and, 2) how much the viviparous phenomenon accounts for germination compared to variation between fruits, individuals and populations of the cactus.Methods: The incidence of vivipary was recorded in 194 plants, and seeds were separated into four putative sources of variance: populations, reproductive categories (VV: viviparous, NV: non-viviparous), individuals within categories and fruits within individuals. The seed germination response in percentage (PGF), mean time (TMG), rate (VG), and synchrony of germination (SG) was evaluated under a randomized complete blocks scheme with three replicates, in experimental units of 25 seeds. Data were analyzed with hierarchical ANOVAs for a linear mixed model.Key results: Reproductive categories accounted for 5-11% of variance and showed significant differences in favor of viviparous phenotypes, with PGF of 35 vs 19% and 91 vs 72%, VG of 1.5 vs 0.5 and 7.9 vs 5.4 seeds/day, and SG of 0.3 vs 0.1, 0.7 vs 0.5 and 0.8 vs 0.6. Buenavista and Tosalibampo populations showed higher percentage, rate and synchrony of germination than the other populations (P<0.05, Student t-test).Conclusions: There is a seed germination pattern associated to vivipary in S. thurberi. The variance accounted by this condition depends on the environment in which seed maturation and germination occur. The seeds from viviparous phenotypes showed higher germination vigor than seeds from non-viviparous plants, revealing potential for seedling recruitment and population growth under drought and salinity stress.Antecedentes y Objetivos: La germinación precoz (vivípara) de semillas en frutos de Stenocereus thurberi se ha correlacionado con mayor velocidad de germinación de las semillas remanentes. Esta investigación compara la germinación de cinco poblaciones de Sinaloa, México, para determinar: 1) si existe un patrón asociado con la germinación precoz de las semillas y 2) cuánto contribuye el fenómeno vivíparo a la germinación, dada la variación entre frutos, individuos y poblaciones de esta especie.Métodos: Se revisó el nivel de viviparidad de 194 plantas y se separaron las semillas en cuatro probables fuentes de varianza: poblaciones, categorías reproductivas (VV: vivíparas y NV: no vivíparas), plantas dentro de categorías y frutos dentro de plantas. Las respuestas de germinación final (PGF), tiempo medio (TMG), velocidad (VG) y sincronía de germinación (SG) se evaluaron en bloques al azar con tres repeticiones, en unidades experimentales de 25 semillas. Los datos se analizaron con ANOVA’s jerárquicos bajo un modelo lineal mixto.Resultados clave: Las categorías reproductivas explicaron 5-11% de la varianza y mostraron diferencias significativas a favor de las vivíparas, con PGF de 35 vs 19% y 91 vs 72%, VG de 1.5 vs 0.5 y 7.9 vs 5.4 semillas/día, y SG de 0.3 vs 0.1, 0.7 vs 0.5 y 0.8 vs 0.6. Las poblaciones de Buenavista y Tosalibampo tuvieron mayor porcentaje, velocidad y sincronía de germinación (prueba t de Student, P<0.05) que las otras poblaciones.Conclusiones: Existe un patrón de germinación asociado con viviparidad en S. thurberi. La varianza asociada con esta condición depende del ambiente de maduración y germinación de las semillas. Los fenotipos vivíparos germinaron con mayor vigor que los no vivíparos, mostrando potencial para apoyar la incorporación de individuos y el crecimiento de la población en condiciones de estrés hídrico y salino

    Biosynthesis of silver nanoparticles using chenopodium ambrosioides

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    ARTICULO INDEXADOBiosynthesis of silver nanoparticles (AgNPs) was achieved using extract of Chenopodium ambrosioides as a reducer and coating agent at room temperature (25∘C). Two molar solutions of AgNO3 (1 mM and 10 mM) and fie extract volumes (0.5, 1, 2, 3, and 5 mL) were used to assess quantity, shape, and size of the particles. Th UV-Vis spectra gave surface plasmon resonance at 434– 436 nm of the NPs synthesized with AgNO3 10 mM and all extract volumes tested, showing a direct relationship between extract volumes and quantity of particles formed. In contrast, the concentration of silver ions was related negatively to particle size. Th smallest (4.9 ± 3.4 nm) particles were obtained with 1 mL of extract in AgNO3 10 mM and the larger amount of particles were obtained with 2 mL and 5 mL of extract. TEM study indicated that the particles were polycrystalline and randomly oriented with a silver structure face centered cubic (fcc) and fourier transform infrared spectroscopy (FTIR) indicated that disappearance of the –OH group band aftr bioreduction evidences its role in reducing silver ions.CCIQS; “Fideicomiso Revocable y de Administracion no. 157304´ COLPOS” and the L´ınea de Investigacion Prioritaria LPI-16´ “Innovacion Tecnol´ ogica” at the “Colegio de Postgraduados´ COLPOS

    Alkaloids from the seed, calyx, and corolla of Erythrina americana Miller and Erythrina coralloides A.DC.

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    Objective: Identified the main alkaloids present in the seeds, calyx and corolla of E. americana and E. coralloides using HPLC/MS Design/methodology/approach: The seeds, calyx and corolla of both species were separated, the preparation of crude extracts of alkaloids was done according to the method described by Games et al. (1974).The crude extracts of alkaloids were analysed using a high performance liquid chromatograph interfaced to a quadrupole ion trap mass spectrometer. Results: The lactonic alkaloids -a-erythroidine and b-erythroidine were the main alkaloids found in E. americana whereas in E. coralloides is characteristic the presence of erythrinine and 8-oxo erythraline. These compounds can be used to distinguish both species. Limitations on study/implications: The use of HPLC-MS technique allowed the detection of a large numbers of structures of alkaloid natures in different parts of plants; however this technique is not available in any laboratory. Findings/conclusions: A large number of erythrinane type alkaloids were found in seed, calyx and corolla. The use of seeds and flowers in the preparations of diverse traditional foods can caused a tranquilizing and sedating effects in the consumers because the presence of lactonic alkaloids. The method of HPLC/MS allowed the detection of alkaloidal structures in flowers and seeds of this species that had not been identifies in previous studies.Objective: To identify the main alkaloids present in the seeds, calyx, and corolla of E. americana and E. coralloides (Fabaceae) using HPLC-MS. Design/methodology/approach: The seeds, calyx, and corolla of both species were separated; the crude alkaloid extracts were prepared according to the method described by Games et al. (1974). The crude alkaloid extracts were analyzed using a high-performance liquid chromatograph interfaced to a quadrupole ion trap mass spectrometer. Results: The lactonic alkaloids -a-erythroidine and b-erythroidine were the main alkaloids found in E. americana, whereas the presence of erythrinine and 8-oxo erythraline is typical of E. coralloides. These compounds can be used to distinguish both species. Limitations on study/implications: The use of the HPLC-MS technique allowed the detection of a large numbers of alkaloidal structures in different parts of the plants; however, this technique is not available in any laboratory. Findings/conclusions: A large number of erythrinane-like alkaloids were found in seed, calyx, and corolla. The use of seeds and flowers in the preparation of diverse traditional dishes can cause soothing and sedating effects in consumers, as a result of the presence of lactonic alkaloids. The HPLC-MS method allowed the detection of alkaloidal structures in flowers and seeds that had not been identified in previous studies about this species.

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

    Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

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    A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

    Probing effective field theory operators in the associated production of top quarks with a Z boson in multilepton final states at root s=13 TeV

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