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Search Results: 1 - 10 of 481 matches for " ADN ribosomal "
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Microorganismos asociados a la rizosfera de jitomate en un agroecosistema del valle de Guasave, Sinaloa, México Rhizosphere microorganisms associated to tomato in an agroecosystem from Guasave Valley, Sinaloa, Mexico
Jesús Damián Cordero-Ramírez,Raquel López-Rivera,Carlos Ligne Calderón-Vázquez,Alejandro Miguel Figueroa-López
Revista mexicana de biodiversidad , 2012,
Abstract: La diversidad de los microorganismos asociados a la rizosfera de diferentes especies vegetales en los suelos, en México se ha estudiado poco y se ha abordado de manera convencional, con técnicas microbiológicas limitadas debido al elevado porcentaje de microorganismos no-cultivables (95-99%). En el presente trabajo se empleó el análisis por secuenciación del ADN ribosomal (ADNr) para evitar esa limitante y explorar mejor la diversidad de los microorganismos cultivables y no-cultivables asociados al jitomate (Solanum lycopersicum L.) en un agroecosistema en Sinaloa. Se empleó ADN genómico extraído del suelo rizosférico para amplificar una región hipervariable en el ADNr empleando oligonucleótidos universales para ADNr procariota y eucariota. El análisis de 194 y 384 secuencias de ADNr de origen procariota y eucariota, respectivamente, mostró que los phyla eucariotes más abundantes fueron Ascomycota (59%), Chlorophyta (21%) y Basidiomycota (12%), y los más abundantes de origen procariote fueron Firmicutes (45%), Proteobacteria (14.7%) y Gemmatimonadetes (13.1%). El presente trabajo representa a la fecha la caracterización más completa de la diversidad de microorganismos de la rizosfera del jitomate. Se discute el papel que especies identificadas en este trabajo, pertenecientes a géneros procariotas (Bacillus y Paenibacillus) y eucariotas (Alternaría), pudieran desempe ar en la rizosfera del jitomate y en el control biológico de fitopatogénos en esta especie. Rhizosphere microorganism diversity associated to different plant species in Mexican soils has been understudied. Most of those studies have been done using conventional microbiological techniques, which present an important limitation due to their incapacity to detect unculturable microorganisms, which represent 95-99% of the total microorganisms in soils. The present work employs ribosomal DNA (rDNA) sequencing to overcome this limitation and to improve exploration of the diversity of culturable and non-culturable microorganisms associated to tomato (Solanum lycopersicum L.) in an agroecosystem from Sinaloa. Genomic DNA from rhizospheric soil was extracted and a hypervariable region on the rDNA was amplified using universal oligonucletides directed to amplify prokaryotic and eukaryotic rDNA. Sequence analysis of 194 and 384 rDNA clones of prokaryotic and eukaryotic origin respectively showed that for eukaryotes, the most abundant phylum was Ascomycota (59%), followed by Chlorophyta (21%) and Basidiomycota (12%), while for Prokaryotes, the phylum Firmicutes (45%) was the most abundant followed by Pro
Diferenciación morfológica y molecular de especies de crisópidos (Neuroptera: Chrysopidae) Morphological and molecular differentiation of lacewing species (Neuroptera: Chrysopidae)
PATRICIA CADENA,FERNANDO áNGEL,LUIS A GóMEZ,RANULFO GONZáLEZ
Revista Colombiana de Entomología , 2007,
Abstract: En el Valle del Cauca (Colombia), se estudió la distribución e identificación de las especies más abundantes de crisópidos en zonas donde se cultiva la ca a de azúcar (Saccharum spp.) con mayor intensidad. Así, se han determinado las especies que podrían ser utilizadas para contrarrestar el efecto del pulgón amarillo Sipha flava (Hemiptera: Aphididae) sobre la producción total de la ca a de azúcar. Aunque las especies y morfotipos del presente estudio son separados utilizando caracteres morfológicos, se evaluó la validez de dichos caracteres. Para esto, se realizó una diferenciación morfológica mediante genitalia interna y una diferenciación molecular, empleando la técnica PCR-RFLP sobre la región 18S del ADN ribosomal, de 11 especies de tres géneros de la familia Chrysopidae (Ceraeochrysa, Chrysoperla y Leucochrysa), algunas de las cuales podrían ser importantes como agentes de control biológico del pulgón amarillo de la ca a de azúcar, S. flava. Los caracteres empleados resultaron ser útiles para distinguir las especies. En el caso de la genitalia interna, mostraron diferentes patrones de las estructuras. En el caso de los datos moleculares, las especies fueron diferenciadas utilizando solo una combinación de iniciadores NS para la amplificación del ADN y la digestión del amplificado producida con una enzima de restricción (NS5-NS6+DraI). Esta información se adiciona al conocimiento taxonómico que se tiene sobre la familia, además puede ayudar a resolver problemas sistemáticos al interior de los géneros. In the Cauca Valley (Colombia), the distribution and identification of the most abundant lacewing species were studied in zones where sugar cane (Saccharum spp.) is cultivated. It has therefore been possible to determine the species that could be used to counter the effect of the yellow aphid Sipha flava (Hemiptera: Aphididae) on the overall production of sugar cane. Although the lacewing species and morphotypes in the current study can be separated using morphological characters, the validity of those characters was studied. To do that, we established a morphological differentiation using internal genitalia and a molecular differentiation using a PCR-RFLP analysis of the 18S rDNA region of 11 species from three genera of the family Chrysopidae (Ceraeochrysa, Chrysoperla, and Leucochrysa), some of whom could be important biological control agents of the yellow sugar cane aphid S. flava. The characters used proved to be useful for distinguishing the species. In the case of internal genitalia, there were different patterns of the structures. In the case
Population structure and genetic variability of Rhodnius prolixus (Hemiptera: Reduviidae) from different geographic areas of Colombia. Estructura poblacional y variabilidad genética de Rhodnius prolixus (Hemiptera: Reduviidae) procedente de diferentes áreas geográficas de Colombia
Diana Carolina López,Carlos Jaramillo,Felipe Guhl
Biomédica , 2010,
Abstract: Introduction. Rhodnius prolixus is the most important vector of Chagas disease in Colombia. Genetic characterization of this species is useful to understand its potential of dispersion. The distribution of the vector and the genetic population structure are important factors for the adequate implementation of control programs and epidemiological surveillance of Chagas disease. Objective. Genetic relationships were established for populations of R. prolixus collected from several habitat types and representative geographic areas of Colombia. A second aim was to assess its population genetic structure and dispersion across Colombia. Materials and methods. Genetic comparisons were made from three domestic populations of R. prolixus from (1) Tolima Province, (2) Cundinamarca Province and (3) the Sierra Nevada of Santa Marta in northern Colombia, and (4) one sylvatic population from Casanare. Two molecular techniques were used to evaluate the genetic structure of these populations-analysis of the ITS-2 of ribosomal DNA by PCR/RFLP and RAPDs. Results. Rhodnius prolixus shows a moderate genetic variability (Fst 0.06-0.15). Among domestic populations, the migration rates found were adequate (Nm>1) to maintain gene flow. A moderate to large degree of genetic differentiation was observed between the sylvatic population from Casanare and the domestic populations from the centre of the country (Tolima and Cundinamarca). Conclusion. The domestic populations of R. prolixus are homogeneous because genetic flow exists between them, and this is favourable to chemical control, while the sylvatic population clusters apart from the domestic populations. Hence the need to study the genetic structure of the sylvatic foci, their possible dispersion routes and the epidemiological risk that they represents. Introducción. Rhodnius prolixus es el vector más importante de la enfermedad de Chagas en Colombia. La caracterización genética de esta especie resulta útil para comprender su potencial de dispersión. La distribución del vector y la estructura genética de sus poblaciones, son factores importantes para implementar de manera adecuada las estrategias de control y vigilancia epidemiológica de la enfermedad de Chagas. Objetivo. Establecer relaciones genéticas entre poblaciones de R. prolixus capturadas en diferentes hábitat y áreas geográficas de Colombia, para dilucidar la estructura genética y dispersión del vector en el territorio colombiano. Materiales y métodos. Se analizaron tres poblaciones domiciliadas de R. prolixus provenientes de Tolima, Cundinamarca y la Sierra Nevada
Ribosomal proteins expression and phylogeny in alpaca (Lama pacos) skin  [PDF]
Junming Bai, Ruiwen Fan, Shanshan Yang, Yuankai Ji, Jianshan Xie, Chang-Sheng Dong
Advances in Bioscience and Biotechnology (ABB) , 2012, DOI: 10.4236/abb.2012.33032
Abstract: Ribosomal proteins (RP) has been reported as a central player in the translation system, and are required for the growth and maintenance of all cell kinds. RP genes form a family of homologous proteins that express in the stable pattern and were used for phylogenetic analysis. Here we constructed a cDNA library of alpaca skin and 13,800 clones were sequenced. In the cDNA library, RP genes from skin cDNA library of alpaca were identified. Then 8 RP genes were selected at random and built the phylogenetic trees from the DNA sequences by using parsimony or maximum likelihood methods for molecular and evolutionary analysis of ribosomal proteins. The results showed that the 42 RP genes of alpaca have been expressed in alpaca skin. They were highly conserved. The phylogeny inferred from all these methods suggested that the evolutionary distances of alpaca RP genes were closer to rat.
Emotional Repercussions in Fathers Triggered by Paternity Testing  [PDF]
Fabíola de Freitas Sch?fer, Edson Júnior Silva da Cruz, Júlia Sursis Nobre Ferro Bucher-Maluschke, Janari da Silva Pedroso
Psychology (PSYCH) , 2017, DOI: 10.4236/psych.2017.86052
Abstract: The present study discusses the emotional repercussions in parents triggered by the process of Deoxyribonucleic Acid (ADN) testing for paternity acknowledgment. The research adopts a qualitative focus for data analyses and uses as tools: interviews with open and closed questions to deal with sociodemographic data for profiling the participants, history of paternity and identification of the father, and family experience of parents and their children. Four men took part in the study, all of them coming from South and Midwest regions of Brazil. Data were categorized according to content analysis. The results evidenced various forms of reactions in fathers triggered by the ADN testing, such as feelings of insecurity, surprise, affection and endearment. The study allowed contributions to analyze paternal psychology concerning feelings of fathers and their care about their children.
Descifrando los mensajes del pasado : análisis del ADN antiguo
Neskuts Izagirre,Satos Alonso,Concepción de la Rúa
Munibe Antropologia-Arkeologia , 2005,
Abstract: El análisis de ADN (ADNa) nos permite estudiar directamente la composición genética de las poblaciones del pasado. Sin embargo, pronto se hicieron patentes las limitaciones metodológicas derivadas del mal estado de preservación del ADNa, así como del enorme riesgo de contaminación con ADN humano momderno. Ello, condujo a la elaboración de una serie de Criterios de Autentificación que deben cumplir todos los trabajos del campo de ADNa para su publicación. Actualmente, los trabajos publicados no son numerosos, ni espectaculares, pero los resultados son reproducibles y su autenticidad esta demostrada. Nuestro equipo viene trabajando desde hace más de 10 a os en este campo. Hemos analizado 5 yacimientos prehistóricos (SJaPL, Longar, Pico Ramos, Urratxa y Aizpea) y uno histórico (Aldaieta) del País Vasco. Los resultados obtenidos hasta el momento, nos están permitiendo indagar en los procesos evolutivos sufridos por la población vasca, constrastar las hipótesis que han sido planteadas con otras evidencias, y concretamente en el yacimiento de Aldaieta, indagar en cuestiones biosociales, como el parentesco, y en el origen de este grupo humano.
A New Isolate of the Genus Malassezia Based on the Sequence Analysis of 26S and ITS1 in Ribosomal DNA
Hossein Mirhendi,Ali Zia,Kuichi Makimura
Cell Journal , 2009,
Abstract: Malassezia species considered to be the etiological agents of pityriasis versicolor andMalassezia follicolitis in humans. Recently, on the basis of molecular data, four new specieswere added to the genus. In total, 11 species have been described and accepted sofar. In this study we describe a new isolate of Malassezia based on the nucleotide sequenceof 26SrDNA and ITS1 regions, as the accepted critical markers for description ofthe species.The yeast was isolated from a hamster. Two primer pairs, one for amplification of D1/D2-26Sr DNA and another for the ITS1 region were used in PCR. The PCR products weresequenced and analyzed to compare with other similar sequences which are already depositedin the GenBank. The 26SrDNA PCR product was also digested with the restrictionenzyme CfoI.Malassezia-specific universal primer pairs successfully amplified the 26srDNA and ITS1regions of the new isolate, providing a single PCR product of about 580 and 280 basepairs, respectively. After digestion of the 26s PCR product with the enzyme CfoI, a uniqueand different RFLP pattern was observed. Sequence analysis of D1/D226s and ITS1 regionswere compared with the same regions in all already described Malassezia species,which implied a different and unique new sequences. The phylogenetic tree of both regionsshowed that the isolate could be a different Malassezia isolate.Regarding the new RFLP pattern of D1/D226SrDBA and the unique nucleotide sequence ofboth D1/D2 26SrDNA and ITS1 regions, we propose the isolate to be a new Malassezia.
Modelagem da combust?o da dinitramida de am?nio por simula??o computacional
Gon?alves, Rene Francisco Boschi;Rocco, José Atílio Fritz Fidel;Iha, Koshun;Machado, Francisco Bolivar Correto;
Química Nova , 2009, DOI: 10.1590/S0100-40422009000700003
Abstract: in this work, the combustion process of ammonium dinitramide, adn, has been modeled in two different situations: decomposition in open environment, with abundant air and decomposition in a rocket motor internal environmental conditions. the profiles of the two processes were achieved, based on molar fractions of the species that compose the products of adn combustion. the velocity of formation and quantity of species in the open environment was bigger than the ones in the rocket motor environment, showing the effect of the different atmosphere in the reactions kinetics.
Les Biopuces : Merveille de nanotechnologie et outil de demain
Nadia ZARI
Technologies de Laboratoire , 2009,
Abstract: Les biopuces sont nées de la rencontre entre la microélectronique, les microsystèmes, la biologie et la chimie. Elles apportent une solution innovante au problème ancien de la détection, de l’identification et du typage de bactéries dans un échantillon. Elles permettent la caractérisation génomique rapide de bactéries pathogènes et facilitent les études épidémiologiques.Ces puces sont développées dans les laboratoires de recherche pour l’étude de la diversité et de l’évolution du monde bactérien, pour rechercher des gènes de résistance aux antibiotiques et pour la caractérisation de communautés bactériennes constituées de centaines d’espèces. L’industrialisation du processus de fabrication et d’utilisation, rendant la technologie robuste tout en en diminuant son co t et permettant son utilisation dans les laboratoires hospitaliers et d’analyses spécialisées.
Molecular identification of Trichogramma cacoeciae Marchal (Hymenoptera: Trichogrammatidae): a new record for Peru
Almeida, Raul P. de;Stouthamer, Richard;
Neotropical Entomology , 2003, DOI: 10.1590/S1519-566X2003000200011
Abstract: discovery of male morphological characters for species identification was a great improvement in trichogramma systematic. however, not all species could be easily identified. in some cases, the lack of males (thelytokous status of species that carry the wolbachia symbiont) made trichogramma identification impossible. this problem was solved via antibiotic and heating treatments for elimination of the bacteria and allowing the production of males. the only trichogramma species reported in which thelytoky is not induced by bacterial infection is t. cacoeciae, so here another means of species identification is needed. this species was identified based on the its2 (internal transcribed spacer 2) sequence, a modern technique that has been proved useful in providing a reliable identification of trichogramma species. here we report the first occurrence of t. cacoeciae in peru and we discuss its distribution in south america.
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