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Resource manipulation reveals flexible allocation rules to growth and reproduction in a Mediterranean evergreen oak

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Journal of Plant Ecology 2014年第1期7卷 77-85页

作者： Fernando Pulido gerardo moreno Eustolia garcía José J.Obrador Raúl Bonal Mario Díaz grupo de Investigación Forestal Ingeniería Forestal y del Medio NaturalUniversidad de ExtremaduraE-10600 PlasenciaCáceresSpain Colegio de Postgraduados Campus TabascoMX-86500 CárdenasTabascoMexico Instituto de Investigación en Recursos Cinegéticos (CSIC-UCLM-JCCM)University of Castilla-La ManchaCiudad RealSpain Department of Biogeography and global Change(BCg-MNCN) Museo Nacional de Ciencias NaturalesCSICE-28006 MadridSpain

Aims In plants,resource allocation to growth and reproduction may depart from trade-off expectations if(i)investment in growth and reproduction relies on different resource pools,(ii)allocation to reproduction is dependent upon reaching some growth threshold or(iii)reproduction is developmentally linked to growth,both functions relying on the same resource *** examined the effects of enhanced resource level on patterns of resource allocation to growth and reproduction in holm oak(Quercus ilex ***),a Mediterranean evergreen *** In the experimental year(2003),we manipulated the amount of soil nutrients in autumn(to increase nutrient uptake during shoot elongation in the following spring)and soil water in summer(to increase water uptake during acorn growth).Indicators of growth and male and female reproduction were estimated in the preexperimental(2002),experimental(2003)and post-experimental(2004)*** Findings Fertilized trees produced significantly longer shoots,but the number of female flowers per shoot was not affected by *** production of male catkins was also enhanced by *** did not affect the production of female flowers or abortion *** and female reproduction showed no consistent relationship in untreated trees,but resource addition elicited a growth-female reproduction trade-off in the experimental *** sign of this significant relationship changed in the post-experimental year,indicating the existence of lagged effects of resource manipulation on acorn ***,patterns of allocation to growth and reproduction varied as a function of sex,resource availability and year,a result consistent with extreme allocational plasticity in holm oak.

关键词： acorn abortion allocational plasticity dehesa growthreproduction trade-offs nutrient addition Quercus ilex resource allocation

Tentative Identification of Phytochemicals and Antioxidant Activities during Fruit-Ripening on Chamaedorea radicalis Mart.

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Phyton-International Journal of Experimental Botany 2020年第2期89卷 361-373页

作者： gerardo Montelongo-Ruiz Yolanda del Rocio moreno-Ramirez Maria Cruz Juarez-Aragon NohemiNino-garcia Reyna Ivonne Torres-Acosta Torres-Castillo Jorge Ariel Universidad Autonoma de Tamaulipas Instituto de Ecologia AplicadaCiudad Victoria87019Mexico Universidad Autonoma de Tamaulipas Unidad Academica Multidisciplinaria ManteCiudad Mante89840Mexico

This work aims to determine the phytochemical characterization of the pericarp of Chamaedorea radicalis *** as a non-timber product with potential to obtain phytochemicals with potential applications in the *** from *** were grouped in four ripening stages named as S1,S2,S3 and S4,according to maturity;S1 the most unripe stage and S4 the completely ripe *** of total phenolic compounds,free radical scavenging activities and total flavonoid contents using spectrophotometric methods were ***,the tentative identification of phytochemicals during fruit ripening was done using *** phenolic compound(TPC)content ranged from 7.24 to 12.53 mg gallic acid equivalents per gram of fresh weight(mg gAE/g FW).Total flavonoids(TF)contents ranged from 0.163 to 0.23 mg of quercetin equivalents per g FW(mg QE/g FW).Free radical scavenging activity against DPPH and ABTS radicals varied from 40.80 to 53.68 and from 22.29 to 37.76 mmol Trolox equivalents g FW(mmol TE/g FW),*** assay in vitro by FRAP(ferric reducing antioxidant power)method showed that S3 was the highest level with antioxidant power while S4 was the lowest with Red ripeness stage showed the lowest contents for all *** spectrometry allowed detection of 26 compounds,including phenolics,alkaloids and ***,Kaempferol 3-neohesperidoside and the four saponins identified were present in all ripeness *** phytochemical identification and the spectrophotometric determinations showed that the pericarp of *** presented antioxidants and compounds related to alkaloids,phenolics and *** presence and abundance of each phytochemical regarding each ripeness stage should be considered.

关键词： Metabolite identification palm free radical scavenging phenolic compounds saponins

Ultrastructural and Physiological Characterization of YELP, a Novel, Yellow, Chlorophyll-Deficient Cell Mutant Line That Develops Etioplast-Like Plastids in the Light

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American Journal of Plant Sciences 2016年第3期7卷 510-524页

作者： Betzaida Jiménez-Francisco Carlos Trejo Hilda Araceli Zavaleta-Mancera Blanca moreno-gómez Edmundo garcía-Moya Florentino Víctor Conde-Martínez gerardo Armando Aguado-Santacruz Potgrado en Botánica Colegio de Postgraduados Texcoco México Campo Experimental Bajío Instituto Nacional de Investigaciones Forestales y Agropecuarias Celaya México Programa de Posgrado Instituto Tecnológico de Roque Celaya México

In this work, we present an ultrastructural and physiological description of a novel chlorophyll-deficient, yellow cell line of the grass Bouteloua gracilis that develops etioplast-like plastids in presence of light (YELP). These mutant cells were compared to the parental, wild-type, highly chlorophyllous cells from which they were isolated. growth analysis, based on fresh and dry weights, indicated that YELP accumulates biomass at a slower rate than the parental, green cells. Besides, YELP developed very low levels of photosynthetic pigments, reaching only 9.3% and 38.4% of chlorophyll a and chlorophyll b, respectively, developed by the wild-type cells. Likewise, the accessory pigments, carotenes and xanthophylls, were only synthesized at 8.0% and 5.4%, respectively, of the levels reached by the green cells. Electron microscopy revealed remarkable differences in plastid ultrastructure between the wild-type and mutant cells. Plastids of YELP were heterogeneous and smaller than those found in wild-type cells. YELP plastids were abnormal with poorly developed membrane systems that prevented the accumulation of chlorophyll and accessory pigments in the mutant cell line. We expect this novel, mutant cell line will provide new tools for studying plastid development and differentiation.

关键词： Cell Suspension Chloroplast Biogenesis Prolamellar Body Ultrastructure

Statins for age related macular degeneration: promising but unproven

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Annals of Eye Science 2021年第4期6卷 26-30页

作者： Martin A.Mainster Ahmed Al-Janabi Ana Boris moreno Andrade gerardo Ledesma-gil Department of Ophthalmology University of Kansas School of MedicinePrairie VillageKansasUSA Royal glamorgan Hospital UK Retina Department Institute of OphthalmologyFundación Conde de ValencianaMexico CityMexico

Statins are used widely to treat hypercholesterolemia and atherosclerotic cardiovascular *** have inflammatory and immunomodulatory effects potentially useful for managing systemic autoimmune diseases such as rheumatoid arthritis,lupus erythematosus and multiple *** also have anti-oxidative and large-vessel endothelial supportive properties that occur independent of their lipid-lowering ***,statins can suppress macrophage and microglial activation responsible for initiating inflammatory cytokine *** than forty percent of adults aged 65 years or older use statins in the United States and Australia,a prevalence that increases with *** effects of statin usage on ophthalmic practice are probably *** disease and age-related macular degeneration(AMD)share common risk factors,consistent with the“vascular model”of AMD pathogenesis that implicates impaired choroidal circulation in Bruch’s membrane lipoprotein *** has a complex multifactorial pathogenesis involving oxidative stress,choroidal vascular dysfunction,dysregulated complement-cascade-mediated inflammation and pro-inflammatory and pro-angiogenic growth *** of these components are hypothetically amenable to the primary(cholesterol lowering)and secondary(anti-inflammatory,anti-oxidative,anti-vasculopathy)effects of statin *** studies have been promising,epidemiological trails have produced conflicting results and three prospective clinical trials have been inconclusive at demonstrating the value of statin therapy for delaying or preventing *** evidence to date has failed to prove conclusively that statins are beneficial for preventing or treating AMD.

关键词： Age-related macular degeneration(AMD) inflammation oxidative stress atherosclerosis statins

Photoluminescence Spectroscopy as a Tool for Quality Control of gaN Thin Film to Be Used in Solar Cell Devices

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Materials Sciences and Applications 2014年第5期5卷 267-270页

作者： guillermo Santana-Rodríguez Adolfo Mejía-Montero Betsabeé Marel Monroy-Peláez Máximo López-López Yenny Lucero Casallas-moreno Manolo Ramírez-López gerardo Contreras-Puente Osvaldo de Melo-Pereira Centro de Investigación y de Estudios Avanzados-IPN México City México Escuela Superior de Física y Matemáticas-Instituto Politécnico Nacional México City México Facultad de Física-Universidad de la Habana Habana City Cuba Instituto de Investigaciones en Materiales-Universidad Nacional Autónoma de México México City México Instituto de Investigaciones en Materiales-Universidad Nacional Autónoma de México México City México Centro de Investigación y de Estudios Avanzados-IPN México City México

The use of III-V and semiconductor nitrides in solar cells has been of interest in the PV-community due to the wide variation range of the band gap in these materials. Particularly, the processing of hetero-junction structures of IngaN/gaN and Si(p)/gaN(n) has been of great interest recently. In this work, the quality of gaN and IngaN thin films grown by Molecular Beam Epitaxy (MBE) on different substrate and buffer layers has been studied by photoluminescence spectroscopy (PL). The PL measurements were processed as function of sample temperature and pump power. In the PL spectra it is possible to observe a strong near band-gap-edge emission and a broad blue, green and yellow luminescence (BL, gL, YL), which can be assigned to the presence of ga and N vacancies, amorphous phases, deep level impurities and structural defects. The relative intensity between the different peaks of the bands related to defects or impurities was studied as a tool for quality control of the films.

关键词： Photoluminescence gallium Nitride Solar Cells

Isolation and Characterization of Mercury Resistant Trichoderma Strains from Soil with High Levels of Mercury and Its Effects on Arabidopsis thaliana Mercury Uptake

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Advances in Microbiology 2018年第7期8卷 600-613页

作者： JoséLuis Hernández-Flores Joségerardo Bernal Melo Andrés Cruz Hernández Miguel A.Ramos López Carlos Saldana gutiérrez Sergio Romero gomez Victor Pérez moreno Rosa P.Calvillo Medina JoséHumberto Valenzuela Soto Sergio Pacheco Hernández george H.Jones Sergio Casas Flores Juan Campos-guillen Laboratorio de Bioseguridad y Análisis de Riesgo Departamento de Ingeniería Genética de PlantasCentro de Investigación y de Estudios Avanzados del IPNIrapuatoGto.México Facultad de Química Universidad Autónoma de QuerétaroCerro de las Campanas s/nQuerétaroQro.México Escuela de Agronomía Universidad De La Salle Bajíocampus Campestre.LeónGto.México Facultad de Ciencias Naturales Universidad Autónoma de QuerétaroAv.De las Ciencias S/NQuerétaroQro.México Centro de Investigación en Química Aplicada Blvd.Enrique Reyna Hermosillo No.140SaltilloCoahuilaMéxico Department of Biology Emory UniversityAtlantaGeorgiaUSA IPICYT División de Biología Molecular.Camino a la presa San JoséNo.2055Colonia Lomas 4a sección.C.P.San Luis PotosíMexico

Traditional mining activities are usually correlated with high levels of soil pollution, which is a major environmental concern. Extensive mining activities have taken place in the San Joaquin region in the State of Querétaro, México resulting in high levels of mercury soil pollution (up to 1532 ± 300 mg/kg). We isolated mercury-resistant fungal strains from the San Joaquin region soils and identified them through morphologic characteristics and ITS rDNA region sequence analysis. We determined that fungi isolated belong to the genus Trichoderma. All the isolates selected showed the ability to catalyze the volatilization of Hg. For air sampling, an active sampling device was constructed and using acid KMnO4 as an absorbent, the concentration of mercury in solution was determined through the cold vapor atomic absorption method. The results show mercury volatilization from the fungal species assay, with a maximum of 213.04 ± 32.6 μg/m3 while mycelium accumulation ranged from less than 17.5 ± 2.9 to 20.0 ± 3.4 μg/g. The fungal isolates were also evaluated for their ability to reduce mercury uptake in Arabidopsis thaliana. These observations suggest the utility of Trichoderma for the mobilization of mercury in those contaminated soils.

关键词： Volatilization Mercury Trichoderma Soil Bioremediation