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2.
Arch. argent. pediatr ; 118(2): 125-: I-129, I, abr. 2020. tab
Article in English, Spanish | LILACS, BINACIS | ID: biblio-1100167

ABSTRACT

Introducción. Investigadores canadienses desarrollaron un cuestionario autoadministrado para indagar sobre la intención de los participantes de actividades de desarrollo profesional continuo (DPC) de transferir los conocimientos adquiridos en ámbitos áulicos a la práctica clínica. Su uso podría facilitar los procesos de mejora de la calidad en dichas actividades de DPC.Objetivo. Realizar la traducción y adaptación transcultural y validación del cuestionario REACTION (A theoRy-basEd instrument to assess the impACT of continuing profesional development activities on profesional behavIOr chaNge) para su uso en la Argentina, a partir de la versión original en inglés.Población y métodos. Se realizó la traducción y adaptación transcultural de los 12 ítems del instrumento, con un proceso de cinco pasos. La validez de constructo se exploró mediante el análisis factorial exploratorio, y la confiabilidad, a través del coeficiente de Cronbach y el coeficiente G.Resultados. La versión final del cuestionario se aplicó a una muestra de 133 médicos asistentes a 9 actividades presenciales de DPC de un hospital universitario de la Ciudad de Buenos Aires (edad promedio: 38 años; el 23,3 %, hombres; el 76 %, médicos de familia). El análisis factorial exploratorio arrojó 3 factores (influencia social, confianza en las capacidades propias y criterio ético). El coeficiente de Cronbach fue 0,82 y el coeficiente G fue 0,72.Conclusiones. Se realizó la adaptación y validación de la versión argentina del instrumento REACTION para evaluar el impacto del DPC enfocado en el entrenamiento de habilidades clínicas en la intención de los médicos de implementarlo en su práctica.


Introduction. Canadian researchers developed a self-administered questionnaire to ask participants of continuing professional development (CPD) activities about their intention to translate the knowledge acquired in the classroom into clinical practice. The questionnaire may facilitate quality improvement processes in such CPD activities.Objective. To translate, cross-culturally adapt and validate the original English REACTION questionnaire (A theoRy-basEd instrument to assess the impACT of continuing professional development activities on professional behavIOr chaNge) for its use in Argentina.Population and methods. The 12 questionnaire items were translated and cross-culturally adapted using a five-step process. The construct validity was assessed using an exploratory factor analysis, whereas reliability, with Cronbach's coefficient and the G coefficient.Results. The final questionnaire version was administered to a sample of 133 physicians who attended 9 CPD activities at a teaching hospital in the Autonomous City of Buenos Aires (average age: 38 years; 23.3 %, men; 76 %, family physicians). The exploratory factor analysis showed 3 factors (social influence, confidence in one's abilities, and ethical judgment). Cronbach's coefficient was 0.82 and the G coefficient, 0.72.Conclusions. The Argentine version of the REACTION questionnaire was adapted and validated to assess the impact of CPD centered on clinical skills training on physicians' intention to implement it in their practice


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Physicians/psychology , Health Knowledge, Attitudes, Practice , Education, Medical, Continuing , Translating , Attitude of Health Personnel , Data Collection , Surveys and Questionnaires , Reproducibility of Results , Adaptation to Disasters
3.
Arch Argent Pediatr ; 118(2): 125-129, 2020 04.
Article in English, Spanish | MEDLINE | ID: mdl-32199047

ABSTRACT

INTRODUCTION: Canadian researchers developed a self-administered questionnaire to ask participants of continuing professional development (CPD) activities about their intention to translate the knowledge acquired in the classroom into clinical practice. The questionnaire may facilitate quality improvement processes in such CPD activities. OBJECTIVE: To translate, cross-culturally adapt and validate the original English REACTION questionnaire (A theoRy-basEd instrument to assess the impACT of continuing professional development activities on professional behavIOr chaNge) for its use in Argentina. POPULATION AND METHODS: The 12 questionnaire items were translated and cross-culturally adapted using a five-step process. The construct validity was assessed using an exploratory factor analysis, whereas reliability, with Cronbach's coefficient and the G coefficient. RESULTS: The final questionnaire version was administered to a sample of 133 physicians who attended 9 CPD activities at a teaching hospital in the Autonomous City of Buenos Aires (average age: 38 years; 23.3 %, men; 76 %, family physicians). The exploratory factor analysis showed 3 factors (social influence, confidence in one's abilities, and ethical judgment). Cronbach's coefficient was 0.82 and the G coefficient, 0.72. CONCLUSIONS: The Argentine version of the REACTION questionnaire was adapted and validated to assess the impact of CPD centered on clinical skills training on physicians' intention to implement it in their practice.


Introducción. Investigadores canadienses desarrollaron un cuestionario autoadministrado para indagar sobre la intención de los participantes de actividades de desarrollo profesional continuo (DPC) de transferir los conocimientos adquiridos en ámbitos áulicos a la práctica clínica. Su uso podría facilitar los procesos de mejora de la calidad en dichas actividades de DPC. Objetivo. Realizar la traducción y adaptación transcultural y validación del cuestionario REACTION (A theoRy-basEd instrument to assess the impACT of continuing profesional development activities on profesional behavIOr chaNge) para su uso en la Argentina, a partir de la versión original en inglés. Población y métodos. Se realizó la traducción y adaptación transcultural de los 12 ítems del instrumento, con un proceso de cinco pasos. La validez de constructo se exploró mediante el análisis factorial exploratorio, y la confiabilidad, a través del coeficiente de Cronbach y el coeficiente G. Resultados. La versión final del cuestionario se aplicó a una muestra de 133 médicos asistentes a 9 actividades presenciales de DPC de un hospital universitario de la Ciudad de Buenos Aires (edad promedio: 38 años; el 23,3 %, hombres; el 76 %, médicos de familia). El análisis factorial exploratorio arrojó 3 factores (influencia social, confianza en las capacidades propias y criterio ético). El coeficiente de Cronbach fue 0,82 y el coeficiente G fue 0,72. Conclusiones. Se realizó la adaptación y validación de la versión argentina del instrumento REACTION para evaluar el impacto del DPC enfocado en el entrenamiento de habilidades clínicas en la intención de los médicos de implementarlo en su práctica.


Subject(s)
Attitude of Health Personnel , Clinical Competence , Education, Medical, Continuing/standards , Surveys and Questionnaires , Adult , Argentina , Canada , Cultural Characteristics , Education, Medical, Continuing/statistics & numerical data , Factor Analysis, Statistical , Female , Humans , Male , Psychometrics , Quality Improvement , Reproducibility of Results , Translations
4.
Arch. argent. pediatr ; 117(5): 314-322, oct. 2019. ilus, tab
Article in English, Spanish | LILACS, BINACIS | ID: biblio-1054958

ABSTRACT

Introducción. La maternidad/paternidad son considerados roles propios de la edad adulta, y el embarazo en la adolescencia, un problema. Esta visión es una construcción social. Este tema complejo presenta matices en las diferentes poblaciones. Los objetivos fueron indagar las percepciones de los adolescentes de una comunidad con alta vulnerabilidad sociosanitaria sobre el embarazo en la adolescencia y explorar cómo pensaban que repercutía en las diferentes esferas de la vida y las conductas sobre la toma de decisiones que conllevaba la maternidad/paternidad en esta etapa. Población y métodos. Se realizó un estudio descriptivo con enfoque cualitativo en la localidad de Boulogne Sur Mer, San Isidro. Se entrevistó a adolescentes de 14 a 19 años entre enero y julio de 2017. Se analizaron sus opiniones con respecto al embarazo en la adolescencia; la repercusión del embarazo en el núcleo familiar, el grupo de amistades y la escuela; la toma de decisiones y reflexiones que conllevaban la maternidad/paternidad; y cómo era atravesado el proceso del embarazo en sí. Resultados. Participaron 20 adolescentes. Se observó que el embarazo en la adolescencia era vivido como problemático, disruptivo, y era resultado de un entramado complejo de causantes. Los propios adolescentes y su entorno transitaban con ambivalencia este proceso, que generaba una distancia entre lo que se pensaba socialmente como deseable y lo que estaba pasando en el barrio. Conclusiones. El embarazo surge como un fenómeno disruptivo en esta etapa, que acarrea sentimientos de ambivalencia, estigmatización, miedo y soledad por parte de los adolescentes.


Introduction. Parenthood is seen as a role played by adults, so teenage pregnancy is considered a problem. Such perspective is a social construct. This is an intricate, nuanced issue that varies depending on the different populations. Our objectives were obtaining the perceptions about teenage pregnancy from adolescents living in a community in a highly vulnerable social and health situation and explore their thoughts on how it impacted the different spheres of life and decision-making behaviors leading to parenthood in this stage. Population and methods. This was a descriptive, qualitative study done in the city of Boulogne Sur Mer, San Isidro. Adolescents aged 14-19 years were interviewed between January and July 2017. Their opinions about the following were analyzed: teenage pregnancy; the impact of pregnancy on the nuclear family, friends, and school; decision-making and considerations about parenthood; and how the pregnancy process itself was experienced. Results. A total of 20 adolescents participated. It was observed that teenage pregnancy was experienced as problematic and disruptive, and as the result of a complex network of causes. Adolescents and their social circle went through this process with ambiguity, resulting in a distance between what is socially perceived as desirable and what was actually occurring in the neighborhood. Conclusions. Pregnancy arises as a disruptive phenomenon in this stage of life, giving rise to feelings of ambiguity, stigmatization, fear, and loneliness among adolescents.


Subject(s)
Humans , Adolescent , Perception , Pregnancy in Adolescence , Evaluation Studies as Topic
5.
Arch Argent Pediatr ; 117(5): 314-322, 2019 10 01.
Article in English, Spanish | MEDLINE | ID: mdl-31560487

ABSTRACT

INTRODUCTION: Parenthood is seen as a role played by adults, so teenage pregnancy is considered a problem. Such perspective is a social construct. This is an intricate, nuanced issue that varies depending on the different populations. Our objectives were obtaining the perceptions about teenage pregnancy from adolescents living in a community in a highly vulnerable social and health situation and explore their thoughts on how it impacted the different spheres of life and decision-making behaviors leading to parenthood in this stage. POPULATION AND METHODS: This was a descriptive, qualitative study done in the city of Boulogne Sur Mer, San Isidro. Adolescents aged 14-19 years were interviewed between January and July 2017. Their opinions about the following were analyzed: teenage pregnancy; the impact of pregnancy on the nuclear family, friends, and school; decision-making and considerations about parenthood; and how the pregnancy process itself was experienced. RESULTS: A total of 20 adolescents participated. It was observed that teenage pregnancy was experienced as problematic and disruptive, and as the result of a complex network of causes. Adolescents and their social circle went through this process with ambiguity, resulting in a distance between what is socially perceived as desirable and what was actually occurring in the neighborhood. CONCLUSIONS: Pregnancy arises as a disruptive phenomenon in this stage of life, giving rise to feelings of ambiguity, stigmatization, fear, and loneliness among adolescents.


Introducción. La maternidad/paternidad son considerados roles propios de la edad adulta, y el embarazo en la adolescencia, un problema. Esta visión es una construcción social. Este tema complejo presenta matices en las diferentes poblaciones. Los objetivos fueron indagar las percepciones de los adolescentes de una comunidad con alta vulnerabilidad sociosanitaria sobre el embarazo en la adolescencia y explorar cómo pensaban que repercutía en las diferentes esferas de la vida y las conductas sobre la toma de decisiones que conllevaba la maternidad/ paternidad en esta etapa. Población y métodos. Se realizó un estudio descriptivo con enfoque cualitativo en la localidad de Boulogne Sur Mer, San Isidro. Se entrevistó a adolescentes de 14 a 19 años entre enero y julio de 2017. Se analizaron sus opiniones con respecto al embarazo en la adolescencia; la repercusión del embarazo en el núcleo familiar, el grupo de amistades y la escuela; la toma de decisiones y reflexiones que conllevaban la maternidad/paternidad; y cómo era atravesado el proceso del embarazo en sí. Resultados. Participaron 20 adolescentes. Se observó que el embarazo en la adolescencia era vivido como problemático, disruptivo, y era resultado de un entramado complejo de causantes. Los propios adolescentes y su entorno transitaban con ambivalencia este proceso, que generaba una distancia entre lo que se pensaba socialmente como deseable y lo que estaba pasando en el barrio. Conclusiones. El embarazo surge como un fenómeno disruptivo en esta etapa, que acarrea sentimientos de ambivalencia, estigmatización, miedo y soledad por parte de los adolescentes.


Subject(s)
Pregnancy in Adolescence/psychology , Social Stigma , Social Support , Adolescent , Argentina , Cross-Sectional Studies , Female , Humans , Interviews as Topic , Male , Pregnancy , Qualitative Research , Young Adult
6.
Microbiol Res ; 223-225: 13-21, 2019.
Article in English | MEDLINE | ID: mdl-31178046

ABSTRACT

Flavobacterium sp. AUG42 is a cellulase-producing bacterium isolated from the Antarctic oligochaete Grania sp. (Annelida). In this work, we report that AUG42 produces a glycoside hydrolase cocktail with CMCase, PASCase and cellobiase activities (optimum pHs and temperatures ranging from 5.5 to 6.5 and 40 to 50 °C, respectively). The time-course analyses of the bacterial growth and cellulase production showed that the cocktail has maximal activity at the stationary phase when growing at 16 °C with filter paper as a cellulosic carbon source, among the tested substrates. The analyses of the CAZome and the identification of secreted proteins by shotgun Mass Spectrometry analysis showed that five glycoside hydrolyses are present in the bacterial secretome, which probably cooperate in the degradation of the cellulosic substrates. Two of these glycoside hydrolyses may harbor putative carbohydrate binding modules, both with a cleft-like active site. The cellulolytic cocktail was assayed in saccharification experiments using carboxymethylcellulose as a substrate and results showed the release of glucose (a fermentable sugar) and other reducing-sugars, after 24 h incubation. The ecological relevance of producing cellulases in the Antarctic environment, as well as their potential use in the bio-refinery industry, are discussed.


Subject(s)
Cellulases/biosynthesis , Cellulases/chemistry , Flavobacterium/enzymology , Flavobacterium/metabolism , Antarctic Regions , Base Sequence , Carbon/metabolism , Carbon Cycle , Carboxymethylcellulose Sodium/metabolism , Catalytic Domain , Cellulase , Cellulases/genetics , Cellulose , Enzyme Assays , Fermentation , Flavobacterium/genetics , Flavobacterium/growth & development , Glucose/metabolism , Glycoside Hydrolases/metabolism , Hydrogen-Ion Concentration , Kinetics , Models, Molecular , Substrate Specificity , Temperature , beta-Glucosidase/metabolism
7.
Ciudad Autónoma de Buenos Aires; Argentina. Ministerio de Salud de la Nación. Dirección de Investigación en Salud; mayo 2017. 1-22 p. tab.
Non-conventional in Spanish | ARGMSAL, BINACIS | ID: biblio-1397911

ABSTRACT

INTRODUCCIÓN El desarrollo profesional continuo (DPC) es el conjunto de actividades educativas que sirven para mantener, adquirir o aumentar los conocimientos y el rendimiento profesional e incluye a la educación médica continua que es un conjunto de medios dirigidos a cambiar la conducta de los médicos para mejorar los resultados en salud de los pacientes. En 2014 un grupo de investigadores canadienses publicó un cuestionario llamado REACTION que permite indagar la intención de los participantes de actividades de DPC de transferir los conocimientos adquiridos a la práctica clínica. OBJETIVO El objetivo general de este trabajo fue realizar la traducción y adaptación transcultural (TATC) del REACTION para su uso en la Argentina. Sus objetivos específicos fueron obtener una versión válida en español, aportar evidencia para la validez del instrumento y explorar la generalizabilidad de sus resultados. MÉTODOS Primero se realizó la TATC y luego se evaluó la validez del instrumento a través de un estudio analítico de corte transversal. La validez se exploró a través del análisis factorial exploratorio (AFE). Se evaluó la consistencia interna a través del coeficiente de Cronbach considerándose apropiado un valor entre 0,70 a 0,90. Se estimó el coeficiente G para valorar la generalizabilidad, considerándose aceptable un valor mayor o igual a 0,7. RESULTADOS Se realizó la TATC del cuestionario en 5 pasos obteniéndose el cuestionario consolidado. Para explorar la validez de constructo se aplicó a una muestra de 133 sujetos constituida por médicos asistentes a 9 actividades presenciales de DPC de un hospital universitario privado de la ciudad de Buenos Aires (edad promedio 38,03 años, 23,3% hombres, 76% médicos de familia). El AFE arrojó 3 factores (influencia social, confianza en las capacidades propias y criterio ético). El coeficiente de Cronbach fue 0,82 y el coeficiente G absoluto fue 0,72. DISCUSIÓN Mediante esta investigación obtuvimos una versión en español del instrumento REACTION que puede ser utilizada en Argentina para valorar el impacto de las DPC en la intención de los médicos de implementar los nuevos conocimientos a su práctica clínica


Subject(s)
Attitude , Attitude of Health Personnel , Surveys and Questionnaires , Education, Medical
8.
Int J Med Mushrooms ; 18(1): 67-74, 2016.
Article in English | MEDLINE | ID: mdl-27279446

ABSTRACT

Fungal lectins constitute excellent ligands for development of affinity adsorbents useful in affinity chromatography. In this work, a lectin was purified from Pycnoporus sanguineus (PSL) mycelium using 3 procedures: by affinity chromatography, using magnetic galactosyl-nanoparticles or galactose coupled to Sepharose, and by ionic exchange chromatography (IEC). The highest lectin yield was achieved by IEC (55%); SDS-PAGE of PSL showed 2 bands with molecular mass of 68.7 and 55.2 kDa and IEC displayed 2 bands at pi 5.5 and 5.2. The lectin agglutinates rat erythrocytes, exhibiting broad specificity toward several monosaccharides, including galactose. The agglutination was also inhibited by the glycoproteins fetal calf fetuin, bovine lactoferrin, bovine transferrin, and horseradish peroxidase. The lectin was then used to synthesize an affinity adsorbent (PSL-Sepharose) and the interaction with glycoproteins was evaluated by analyzing their chromatographic behaviors. The strongest interaction with the PSL-derivative was observed with transferrin, although lower interactions were also displayed toward fetuin and lactoferrin. These results indicate that the purified PSL constitutes an interesting ligand for the design of affinity adsorbents to be used (i.e., in glycoprotein purification).


Subject(s)
Lectins/isolation & purification , Pycnoporus/chemistry , Transferrin/metabolism , Agglutination/drug effects , Animals , Cattle , Chromatography, Affinity , Chromatography, Ion Exchange , Erythrocytes/drug effects , Fungal Proteins/isolation & purification , Fungal Proteins/metabolism , Galactose/metabolism , Glycoproteins/isolation & purification , Glycoproteins/metabolism , Lectins/metabolism , Ligands , Molecular Weight , Mycelium/chemistry , Rats
10.
Anal Chem ; 86(24): 12159-65, 2014 Dec 16.
Article in English | MEDLINE | ID: mdl-25417550

ABSTRACT

The development of sensitive and easy-to-use biosensors that allow an adequate characterization of specific weak biological interactions like carbohydrate-lectin interactions still remains challenging today. Nanoparticles functionalized with carbohydrates are one of the most powerful systems for studying carbohydrate-lectin interactions, because they mimic the multivalent presentation of carbohydrates encountered in nature, for example when viruses and bacteria bind to cells. On the basis of the model system glucose-Concanavalin A (ConA), we explore the application of Transient Magnetic Birefringence (TMB) to study these weak interactions, using glucose-functionalized colloidal magnetite nanoparticles (NPs) as probes. We demonstrate that the binding dynamics can be monitored and derive a model to obtain the apparent cooperativity. For our studies, we use nanoparticles of 6 and 8 nm in diameter. The ConA-generated response shows apparent cooperativity, due to the cross-linking of nanoparticles by the ConA tetramer which has four binding sites. Cooperativity is higher for 6 nm NPs, possibly due to a better accessibility of all four ConA binding sites on smaller NPs, enhancing cross-linking. For this system, we find a detection limit of 3-23 nM.


Subject(s)
Concanavalin A/chemistry , Glucose/chemistry , Magnetics , Nanoparticles , Microscopy, Electron, Transmission
11.
Appl Biochem Biotechnol ; 172(4): 2081-90, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24338208

ABSTRACT

A lectin was isolated from fruiting bodies of the mushroom Gymnopilus spectabilis (GSL) by ionic exchange chromatography. The lectin agglutinates mouse red cells exhibiting broad specificity towards several monosaccharides including the N-acetylneuraminic acid. Agglutination was also inhibited by the glycoproteins: fetuin, lactoferrin, and recombinant erythropoietin. GSL is a glycoprotein possessing 16 % of carbohydrates; the SDS-PAGE showed two bands with molecular mass of 52.1 and 64.4 kDa. Isoelectric focusing displayed microheterogeneity, with two bands at pIs 5.1 and 5.3. The lectin was stable between pH 2 and pH 8 while at pH 10, the agglutination decayed to 50 % of initial activity. Incubation at 40 and 80 °C led to 50 and 100 % loss in activity of the lectin, respectively. Synthesized GSL-Sepharose interacts with serum pregnant mare gonadotropin, and at least two subpopulations of this glycoprotein were separated. There was no interaction between transferrin and soluble GSL while a partial recognition was achieved with GSL-Sepharose. The terminal sialic acid seems to play an active role in modifying the interaction with GSL, depending if the lectin is in a soluble or immobilized form. The purified lectin inhibited in vitro the growth of Staphylococcus aureus and Aspergillus niger.


Subject(s)
Agaricales/metabolism , Lectins/metabolism , Basidiomycota/metabolism , Fruiting Bodies, Fungal/metabolism , Glycoproteins/metabolism
12.
J Basic Microbiol ; 54(2): 89-96, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23463633

ABSTRACT

Aqueous extracts of basidiomycete fungi were screened for the presence of lectins by hemagglutination (HA) assays with mouse, rabbit, and sheep red blood cells. From mycelia and/or fruiting bodies, 23 extracts were prepared; 15 extracts exhibited HA activity towards mouse erythrocytes, with specific activities ranging from 12 to 440 lectin units (LU) mg(-1) protein. In HA inhibition assays, 43 carbohydrates including mono-, di-, tri-, tetrasaccharides, glycoproteins, and polysaccharides were tested as haptens, to determine the saccharide-binding specificities of the lectins. A novel lectin with specificity towards N-acetyl-glucosamine was purified from mycelia of Punctularia atropurpurascens using affinity chromatography on chitosan-Sepharose. The lectin has a subunit molecular mass of 67 kDa determined by SDS-PAGE and a pI of 5.0.


Subject(s)
Basidiomycota/chemistry , Erythrocytes/cytology , Hemagglutination/drug effects , Lectins/isolation & purification , Acetylglucosamine/chemistry , Animals , Erythrocytes/metabolism , Fruiting Bodies, Fungal/chemistry , Lectins/pharmacology , Mice , Mycelium/chemistry , Rabbits , Sheep
13.
J Nat Med ; 67(2): 247-54, 2013 Apr.
Article in English | MEDLINE | ID: mdl-22645079

ABSTRACT

The Tn antigen (GalNAc-O-Ser/Thr) is one of the most specific human cancer-associated structures. In the present study we characterize the biochemical and functional properties of the Myrsine coriacea lectin (McL). We show that McL is an unusual high molecular weight highly glycosylated protein, which displays a strong Tn binding activity. The lectin exhibits in vitro inhibition of proliferation in the six cancer cell lines evaluated, in a dose-dependent manner (the strongest activity being against HT-29 and HeLa cells), whereas it does not exhibit toxicity against normal lymphocytes. McL could be exploited in the design of potential new tools for the diagnosis or treatment of cancer.


Subject(s)
Antigens, Tumor-Associated, Carbohydrate/metabolism , Lectins/metabolism , Lectins/pharmacology , Primulaceae/chemistry , Antineoplastic Agents/adverse effects , Antineoplastic Agents/metabolism , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , HT29 Cells , HeLa Cells , Humans , Lectins/adverse effects , Lymphocytes/drug effects
14.
Environ Biosafety Res ; 9(3): 147-54, 2010.
Article in English | MEDLINE | ID: mdl-21975255

ABSTRACT

The cultivation of genetically modified (GM) Bt maize (Zea mays L.) events MON810 and Bt11 is permitted in Uruguay. Local regulations specify that 10% of the crop should be a non-GM cultivar as refuge area for biodiversity, and the distance from other non-GM maize crops should be more than 250 m in order to avoid cross-pollination. However, the degree of cross-fertilization between maize crops in Uruguay is unknown. The level of adventitious presence of GM material in non-GM crops is a relevant issue for organic farming, in situ conservation of genetic resources and seed production. In the research reported here, the occurrence and frequency of cross-fertilization between commercial GM and non-GM maize crops in Uruguay was assessed. The methodology comprised field sampling and detection using DAS-ELISA and PCR. Five field-pair cases where GM maize crops were grown near non-GM maize crops were identified. These cases had the potential to cross-fertilize considering the distance between crops and the similarity of the sowing dates. Adventitious presence of GM material in the offspring of non-GM crops was found in three of the five cases. Adventitious presence of event MON810 or Bt11 in non-GM maize, which were distinguished using specific primers, matched the events in the putative sources of transgenic pollen. Percentages of transgenic seedlings in the offspring of the non-GM crops were estimated as 0.56%, 0.83% and 0.13% for three sampling sites with distances of respectively 40, 100 and 330 m from the GM crops. This is a first indication that adventitious presence of transgenes in non-GM maize crops will occur in Uruguay if isolation by distance and/or time is not provided. These findings contribute to the evaluation of the applicability of the "regulated coexistence policy" in Uruguay.


Subject(s)
Gene Flow , Plants, Genetically Modified , Transgenes , Zea mays/genetics , Hybridization, Genetic , Uruguay
15.
Arch Microbiol ; 189(5): 519-24, 2008 May.
Article in English | MEDLINE | ID: mdl-18094958

ABSTRACT

Azospirillum sp promotes the growth of many important crop plants. We demonstrated lectin binding activity in outer-membrane protein extracts of A. brasilense Sp7 by hemagglutination assays. The lectin specifically recognised the exopolysaccharide (EPS) produced by aggregated cells. Affinity chromatography using EPS-Sepharose was used to identify a 67 kDa outer-membrane lectin (OML) that recognised a binding region in the extracellular polysaccharide. Results show the specific recognition and binding between EPS and OML. The potential relationship between cell-to-cell aggregation and the OML-EPS interaction is discussed.


Subject(s)
Azospirillum brasilense/metabolism , Bacterial Outer Membrane Proteins/metabolism , Lectins/metabolism , Polysaccharides, Bacterial/metabolism , Arabinose/metabolism , Bacterial Adhesion , Chromatography, Affinity , Chromatography, Agarose , Hemagglutination Inhibition Tests , Protein Binding , Substrate Specificity
16.
Article in English | MEDLINE | ID: mdl-15063331

ABSTRACT

Preparation of Concanavalin A-adsorbents by immobilization on Sepharose activated with 1-cyano-4-(dimethylamino)-pyridinium tetrafluoroborate (CDAP-reagent) is reported. High immobilization yields of lectin (above 90%) were attained using an optimized CDAP-activating protocol. The effect of ligand density on the performance of the adsorbent for specific binding of glycoproteins was studied using horseradish peroxidase (HRP) as a model. Adsorption yields of pure HRP exceeding 90% were obtained with Con A-derivatives containing not < 20 mg of immobilized Con A/ml of packed gel. With lectin content of 2 mg/(ml of packed gel), only 20% of HRP was adsorbed. Purification of peroxidase from horseradish roots extract was successfully accomplished on Con A-Sepharose with high Con A content.


Subject(s)
Concanavalin A/chemistry , Horseradish Peroxidase/isolation & purification , Plant Roots/chemistry , Adsorption , Chromatography, Affinity , Electrophoresis, Polyacrylamide Gel
17.
J Chromatogr B Analyt Technol Biomed Life Sci ; 790(1-2): 365-72, 2003 Jun 25.
Article in English | MEDLINE | ID: mdl-12767345

ABSTRACT

Optimized procedures for the affinity purification of soybean agglutinin (SBA) from soybean flour, and its further immobilization, were developed. Lectin purification on galactosyl-Sepharose yielded 44.5+/-3.5 mg of pure SBA/50 g of flour. To prepare SBA adsorbents, the lectin was immobilized onto 1-cyano-4-(dimethylamino)pyridinium tetrafluoroborate (CDAP) activated Sepharose with high yields (77%). Feasibility of the use of this improved SBA adsorbent for affinity purification of Streptococcus pneumoniae capsular polysaccharides from strain 14 (CPS-14) at laboratory scale was demonstrated. Using SBA-Sepharose adsorbent (7.0 mg lectin per ml), amounts of 6.3 mg of pure CPS-14 per cycle were produced, the adsorbent being reused up to four times without loss of capacity.


Subject(s)
Chromatography, Affinity/methods , Plant Lectins/isolation & purification , Polysaccharides/isolation & purification , Soybean Proteins/isolation & purification , Electrophoresis, Polyacrylamide Gel
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