Validation of a counseling guide for adherence to antiretroviral therapy using implementation science / Validação de um guia de aconselhamento para a adesão ao tratamento antirretroviral usando ciência da implementação / Validación de Guía de Consejería para adherencia al tratamiento antirretroviral usando ciencia de la implementación

Objective: to determine the contents that must be included in the usual counseling to improve the adherence to antiretroviral therapy (ART) of HIV patients, according to their different levels of alcohol consumption, and to determine the validity of the Counseling Guide in improving the adherence to ART in patients who consume alcohol using Implementation Science. Method: this is an observational study with formative and validation phases. The formative phase defined the content, approach and structure of the counseling. Validation included focus groups with patients and nurses, trial process by an expert and a pilot test. The criteria evaluated based on Implementation Science were: intervention source, evidence strength and quality, relative advantage, and complexity. The following criteria were also evaluated: usefulness, practicality, acceptability, sustainability, effectiveness; content consistency and congruence; procedural compliance and difficulties, and time spent in counseling. Results: the strength of evidence of the counseling is High-IIA, with strong level of recommendation and presenting usefulness, practicality, acceptability, sustainability and effectiveness. Eight in 11 experts argued that the Guide is clear, consistent and congruent. Initial counseling takes around 24 minutes; and follow-up counseling, 21. The instruments of the Guide present reliability levels between good and high (0.65 ≥ alpha ≤ 0.92). Conclusion: the Counseling Guide is valid to improve the adherence to antiretroviral therapy in patients who consume alcohol.

Objetivo: determinar os conteúdos que devem ser incluídos no aconselhamento habitual para melhorar a adesão ao TARV de pacientes com HIV, conforme seus diferentes níveis de consumo de álcool, e determinar a validade do Guia de Aconselhamento para melhorar a adesão ao TARV em pacientes que consomem álcool, usando a Ciência da Implementação. Método: estudo observacional com fase formativa e de validação. A fase formativa permitiu definir o conteúdo, a abordagem e a estrutura do aconselhamento. A validação incluiu grupos focais com pacientes e enfermeiras, processo de julgamento de especialista e teste piloto. Estes foram os critérios avaliados com base na Ciência da Implementação: fonte de intervenção, força e qualidade da evidência, vantagem relativa e complexidade. Foram avaliados ainda: utilidade, praticidade, aceitabilidade, sustentabilidade, efetividade; consistência e congruência do conteúdo; cumprimento, dificuldades do procedimento e tempo empregado no aconselhamento. Resultados: o aconselhamento tem força de evidência Alta -IIA, forte nível de recomendação, apresenta utilidade, praticidade, aceitabilidade, sustentabilidade e efetividade. Oito de 11 especialistas argumentaram que o Guia é claro, consistente e congruente. O aconselhamento de início leva em torno de 24 minutos; e o de acompanhamento, 21. Os instrumentos do Guia têm um nível de confiabilidade entre bom e alto (0,65 ≥ alfa ≤ 0,92). Conclusão: o guia de aconselhamento é válido para melhorar a adesão ao tratamento antirretroviral em pacientes que consomem álcool.

Objetivo: determinar los contenidos necesarios a incluir a la consejería habitual para mejorar la adherencia al TARV de pacientes con VIH según sus diferentes niveles de consumo de alcohol, y determinar la validez de la Guía de Consejería para mejorar la adherencia al TARV en paciente que consumen alcohol usando Ciencia de la Implementación. Método: estudio Observacional con fase formativa y de validación. La fase formativa permitió definir el contenido, enfoque y estructura de la consejería. La validación incluyó grupos focales con pacientes y enfermeras, juicio experto y prueba piloto. Los criterios evaluados en base a la Ciencia de la Implementación fueron: fuente de intervención, fuerza y calidad de la evidencia, ventaja relativa y complejidad. También se evaluó: utilidad, practicidad, aceptabilidad, sostenibilidad, efectividad; consistencia y congruencia del contenido; cumplimiento, dificultades del procedimiento y tiempo empleado en la consejería. Resultados: la consejería tiene fuerza de evidencia Alta -IIA, fuerte nivel de recomendación, presenta utilidad, practicidad, aceptabilidad, sostenibilidad y efectividad. Ocho de 11 expertos, sostuvieron que la Guía es clara, consistente y congruente. La consejería de inicio toma en promedio 24 minutos y 21 minutos la de seguimiento. Los instrumentos de la Guía tienen un nivel de fiabilidad entre bueno y alto (0,65 ≥ alfa ≤ 0,92). Conclusión: la guía de consejería es válida para mejorar la adherencia al tratamiento antirretroviral en pacientes que consumen alcohol.

Cirugía de hombro en posición silla de playa: estrategias y recomendaciones para la prevención de complicaciones isquémicas / Strategies and recommendations for the prevention of ischemic complications in beach chair position for shoulder surgery

Beach chair position is require for Shoulder surgery frequently for proper resolution. The stroke associated with shoulder surgery is a rare complication and probably underreported. The objective of this article is to review the pathophysiology of the ischemic damage associated with beach chair position, learn about strategies and develop recommendations to minimize risks.

La cirugía de hombro (CH), requiere y requerirá colocar a los pacientes en la posición en silla de playa (PSP), cada vez con mayor frecuencia para su adecuada resolución. El asociado a CH, es una complicación poco frecuente y probablmente subreportada. El objetivo de esta revisión, es repasar la fisiopatología del daño isquémico asociado a PSP, conocer estrategias y elaborar recomedaciones destinadas a minimizar riesgos.

Validation of a counseling guide for adherence to antiretroviral therapy using implementation science / Validação de um guia de aconselhamento para a adesão ao tratamento antirretroviral usando ciência da implementação / Validación de Guía de Consejería para adherencia al tratamiento antirretroviral usando ciencia de la implementación

Objective: to determine the contents that must be included in the usual counseling to improve the adherence to antiretroviral therapy (ART) of HIV patients, according to their different levels of alcohol consumption, and to determine the validity of the Counseling Guide in improving the adherence to ART in patients who consume alcohol using Implementation Science. Method: this is an observational study with formative and validation phases. The formative phase defined the content, approach and structure of the counseling. Validation included focus groups with patients and nurses, trial process by an expert and a pilot test. The criteria evaluated based on Implementation Science were: intervention source, evidence strength and quality, relative advantage, and complexity. The following criteria were also evaluated: usefulness, practicality, acceptability, sustainability, effectiveness; content consistency and congruence; procedural compliance and difficulties, and time spent in counseling. Results: the strength of evidence of the counseling is High-IIA, with strong level of recommendation and presenting usefulness, practicality, acceptability, sustainability and effectiveness. Eight in 11 experts argued that the Guide is clear, consistent and congruent. Initial counseling takes around 24 minutes; and follow-up counseling, 21. The instruments of the Guide present reliability levels between good and high (0.65 ≥ alpha ≤ 0.92). Conclusion: the Counseling Guide is valid to improve the adherence to antiretroviral therapy in patients who consume alcohol.

Objetivo: determinar os conteúdos que devem ser incluídos no aconselhamento habitual para melhorar a adesão ao TARV de pacientes com HIV, conforme seus diferentes níveis de consumo de álcool, e determinar a validade do Guia de Aconselhamento para melhorar a adesão ao TARV em pacientes que consomem álcool, usando a Ciência da Implementação. Método: estudo observacional com fase formativa e de validação. A fase formativa permitiu definir o conteúdo, a abordagem e a estrutura do aconselhamento. A validação incluiu grupos focais com pacientes e enfermeiras, processo de julgamento de especialista e teste piloto. Estes foram os critérios avaliados com base na Ciência da Implementação: fonte de intervenção, força e qualidade da evidência, vantagem relativa e complexidade. Foram avaliados ainda: utilidade, praticidade, aceitabilidade, sustentabilidade, efetividade; consistência e congruência do conteúdo; cumprimento, dificuldades do procedimento e tempo empregado no aconselhamento. Resultados: o aconselhamento tem força de evidência Alta -IIA, forte nível de recomendação, apresenta utilidade, praticidade, aceitabilidade, sustentabilidade e efetividade. Oito de 11 especialistas argumentaram que o Guia é claro, consistente e congruente. O aconselhamento de início leva em torno de 24 minutos; e o de acompanhamento, 21. Os instrumentos do Guia têm um nível de confiabilidade entre bom e alto (0,65 ≥ alfa ≤ 0,92). Conclusão: o guia de aconselhamento é válido para melhorar a adesão ao tratamento antirretroviral em pacientes que consomem álcool.

Objetivo: determinar los contenidos necesarios a incluir a la consejería habitual para mejorar la adherencia al TARV de pacientes con VIH según sus diferentes niveles de consumo de alcohol, y determinar la validez de la Guía de Consejería para mejorar la adherencia al TARV en paciente que consumen alcohol usando Ciencia de la Implementación. Método: estudio Observacional con fase formativa y de validación. La fase formativa permitió definir el contenido, enfoque y estructura de la consejería. La validación incluyó grupos focales con pacientes y enfermeras, juicio experto y prueba piloto. Los criterios evaluados en base a la Ciencia de la Implementación fueron: fuente de intervención, fuerza y calidad de la evidencia, ventaja relativa y complejidad. También se evaluó: utilidad, practicidad, aceptabilidad, sostenibilidad, efectividad; consistencia y congruencia del contenido; cumplimiento, dificultades del procedimiento y tiempo empleado en la consejería. Resultados: la consejería tiene fuerza de evidencia Alta -IIA, fuerte nivel de recomendación, presenta utilidad, practicidad, aceptabilidad, sostenibilidad y efectividad. Ocho de 11 expertos, sostuvieron que la Guía es clara, consistente y congruente. La consejería de inicio toma en promedio 24 minutos y 21 minutos la de seguimiento. Los instrumentos de la Guía tienen un nivel de fiabilidad entre bueno y alto (0,65 ≥ alfa ≤ 0,92). Conclusión: la guía de consejería es válida para mejorar la adherencia al tratamiento antirretroviral en pacientes que consumen alcohol.

Parasitism and predation of the planthopper Tagosodes orizicolus (Homoptera: Delphacidae) by a dryinid parasitoid in Costa Rica / Parasitismo y depredación del saltamontes Tagosodes orizicolus (Homoptera: Delphacidae) por un parasitoide dryinido en Costa Rica

We analyzed the effect of predation and parasitism by the native dryinid Haplogonatopus hernandezae as a natural enemy of the rice pest Tagosodes orizicolus under controlled conditions in an insectary in Costa Rica. We found no change in the proportion of T. orizicolus nymphs that were fed upon, parasitized, and that showed no apparent damage throughout the adult stage in H. hernandezae, which favors a stable control of the pest. The percentage of T. orizicolus nymphs that were parasitized (37 %) and preyed upon (36.5 %) was similar, eliminating 73,5 % of the total nymphs causing damage to the rice plants (N = 1 099). Of the total 324 parasitized nymphs, female nymphs were more parasitized than male nymphs (95 % and 5 % respectively) and dryinids developed more successfully in female host nymphs. These tendencies did not change with dryinid age. Survival of dryinids was higher in female T. orizicolus, both for larvae that emerged from the host and pupated, and for pupae that moulted to adults. In cages where the nymphs had no contact with dryinids we found a higher amount of males than females (57.44 ± 28.5 vs 45.22 ± 25.85). In contrast, when the nymphs were in contact with dryinids, the sex ratio was two females to one male reaching adulthood since the dryinids fed more on male nymphs (N = 692). Our results indicate that female dryinids prefer to oviposit in female T. orizicolus nymphs and prey on males. Reproduction by parthenogenesis, acceleration of the development in an insectary with controlled conditions and eficiency of H. hernandezae as a parasitoid and predator indicate that this dryinid is an effective biological control agent of T. orizicolus. Rev. Biol. Trop. 57 (Suppl. 1): 203-211. Epub 2009 November 30.

En un insectario en condiciones controladas analizamos los efectos de depredación y parasitismo del dryinido Haplogonatopus hernandezae, enemigo natural del vector del virus de la hoja blanca Tagosodes orizicolus. Nuestros resultados indican que la proporción de depredación y parasitismo es estable a lo largo de la vida del dryinido lo cual favorece un control continuo eliminando 73% de la plaga (N = 1 099). De un total de 324 ninfas de T. orizicolus parasitadas, las hembras fueron más parasitadas que los machos y las larvas del dryinido se lograron desarrollar exitosamente a partir de ninfas hembra en contraste con las ninfas macho. Encontramos una mayor proporción de machos en comparación con las hembras en las jaulas de T. orizicolus en que las ninfas no tuvieron ningún contacto con hembras del dryinido (57.44 ± 28.5 vs. 45.22 ± 25.85). Al contrario, cuando las ninfas estuvieron en contacto con las hembras del dryinido, la proporción de sexos fue de dos hembras por cada macho. Este resultado indica que las hembras del dryinido prefieren ovipositar en las hembras de T. orizicolus y alimentarse de las ninfas macho. La reproducción por partenogénesis, aceleración de las etapas de desarrollo en condiciones controladas, y la eficiencia como parasitoide y depredador de este dryinido indican su efectividad como agente de control biológico de T. orizicolus.

Optimization of coffee (Coffea arabica) transformation parameters using uidA and hpt genes: effect of osmotic pre-treatment, helium pressure and target distance / Optimización de los parámetros de transformación del café (Coffea arabica) utilizando los genes uidA y hpt: efecto del pretratamiento osmótico, presión de helio y distancia objetivo

The aim of this work was to optimize the biolistic delivery parameters that affect the DNA delivery and stable expression of marker genes into coffee tissues (Coffea arabica. L. cvs. Caturra and Catuaí). The effect of osmotic preculture length, osmotic concentration of medium, Helium pressure and target distance on transient expression of the uidA gene in coffee leaves and somatic embryos were tested. The highest transient uidA expression was obtained when Caturra (18.3±2.8) and Catuaí (6.8±2.0) leaves and Catuaí embryos (80.0±7.4) were cultured for 5h on Yasuda medium complemented with 0.5M Mannitol +0.5M Sorbitol. The combination of 1100psi and a target distance of 9cm resulted in the highest number of blue spots per Caturra leaf segment (23.6±3.9), whereas for the Catuaí variety the combination of 1100psi and a target distance of six (10.2±1.9) and nine (8.2±1.9) cm gave the highest number of blue spots per leaf segment. The optimized protocol was tested with pCAMBIA 1 301 (uidA gene and the hpt gene), pCAMBIA 1 305.2 (uidA version GUSPlus ™ and the hpt gene) and pCAMBIA 1 301-BAR (uidA gene and the bar gene). The highest number of blue spots was obtained when Caturra (54.6±5.7) and Catuaí (28.9±4.3) leaves were bombarded with pCAMBIA 1 305.2. Selection of bombarded coffee tissues with 100mg/l hygromicyn caused the oxidation of tissues. Rev. Biol. Trop. 57 (Suppl. 1): 151-160. Epub 2009 November 30.

La presente investigación tuvo como objetivo optimizar los parámetros que afectan la incorporación y expresión de genes marcadores mediante biobalística en segmentos de hoja y embriones somáticos de café (Coffea arabica. L. cvs. Caturra y Catuaí). La mayor expresión transitoria del gen uidA en segmentos de hoja de Caturra (18.3±2.8) y Catuaí (6.8±2.0) y embriones somáticos de Catuaí (80.0±7.4) se obtuvo al cultivar los explantes por cinco horas previo al bombardeo en el medio Yasuda complementado con 0.5M mannitol+0.5M sorbitol. Asimismo, se obtuvo una mayor expresión transitoria del gen uidA al bombardear los segmentos de hoja de Caturra y Catuaí y embriones somáticos de Catuaí con una presión de helio de 1 100psi y una distancia de bombardeo de 6 o 9 cm.

Histology of somatic embryogenesis in rice (Oryza sativa cv. 5272) / Histología de la embriogénesis somática en arroz (Oryza sativa cv. 5272)

Rice (Oryza sativa cv. 5272) embryogenic calli were obtained from mature zygotic embryos culture on Murashige & Skoog (1962) medium supplemented with 2.5 mg/l 2,4- dichlorophenoxyacetic acid. Histological analysis of somatic embryogenesis revealed that after two weeks of culture of explants on the callus induction medium, somatic embryo development began with a cluster of proembryogenic cells in the peripheral region of the calli. The outer cell layer of embryogenic calli consisted of small and isodiametric cells with a dense cytoplasm and a prominent nucleus and nucleolus; whereas the inner cell layer is composed of large cells with small nucleus and large vacuole. These embryogenic cells underwent a series of organized divisions and formed the proembryo with a well-defined protodermis. Rev. Biol. Trop. 57 (Suppl. 1): 141-150. Epub 2009 November 30.

Los estudios anatómicos e histológicos de los callos embriogénicos de arroz (Oryza sativa) mostraron que estos se originan del epitelio escutelar de los embriones cigóticos maduros. Al crecer en un medio Murashige y Skoog (1962) suplementado con 2.5 mg/l 2,4-D, presentan grupos de células embriogénicas en las zonas periféricas, las cuales a su vez darán lugar a la formación de proembriones y de embriones somáticos. Las células de los callos embriogénicos se caracterizan por tener núcleo y nucleolo conspícuos, forma isodiámetrica, citoplasma denso y están acompañadas de células adyacentes con abundantes gránulos de almidón. Los embriones somáticos completan su desarrollo para dar formación a plántulas completas, al estar en un medio de regeneración. Los estudios histológicos permitieron observar la expresión transitoria del gen uidA en grupos de células de las capas más externas de los callos embriogénicos sometidos al método de transformación genética por biobalística.

El organismo humano: funciones de nutrición, relación y control: libro 2

Contenido: Un sistema complejo y abierto. De la célula al organismo humano. La complejidad del organismo humano. Funciones del organismo humano. Nutrición. Funciones de relación y control...

Biología: el ecosistema y la preservación del ambiente: libro 5

Contenido: Individuo y población. La vida en comunidad. Ecosistemas. El hombre y el ambiente...

A reliable bioassay procedure to evaluate per os toxicity of Bacillus thuringiensis strains against the rice delphacid, Tagosodes orizicolus (Homoptera: Delphacidae)

A reliable bioassay procedure was developed to test ingested Bacillus thuringiensis (Bt) toxins on the rice delphacid Tagosodes orizicolus. Initially, several colonies were established under greenhouse conditions, using rice plants to nurture the insect. For the bioassay, an in vitro feeding system was developed for third to fourth instar nymphs. Insects were fed through Parafilm membranes on sugar (10 % sucrose) and honey bee (1:48 vol/vol) solutions, observing a natural mortality of 10-15 % and 0-5 %, respectively. Results were reproducible under controlled conditions during the assay (18±0.1 °C at night and 28±0.1 °C during the day, 80 % RH and a 12:12 day:light photoperiod). In addition, natural mortality was quantified on insect colonies, collected from three different geographic areas of Costa Rica, with no significant differences between colonies under controlled conditions. Finally, bioassays were performed to evaluate the toxicity of a Bt collection on T. orizicolus. A preliminary sample of twenty-seven Bt strains was evaluated on coarse bioassays using three loops of sporulated colonies in 9 ml of liquid diet, the strains that exhibited higher percentages of T. orizicolus mortality were further analyzed in bioassays using lyophilized spores and crystals (1 mg/ml). As a result, strains 26-O-to, 40-X-m, 43S-d and 23-O-to isolated from homopteran insects showed mortalities of 74, 96, 44 and 82 % respectively while HD-137, HD-1 and Bti showed 19, 83 and 95 % mortalities. Controls showed mortalities between 0 and 10 % in all bioassays. This is the first report of a reliable bioassay procedure to evaluate per os toxicity for a homopteran species using Bacillus thuringiensis strains. Rev. Biol. Trop. 55 (2): 373-383. Epub 2007 June, 29.

Se desarrolló una metodología de bioensayo para evaluar toxinas de Bacillus thuringiensis (Bt) ingeridas por Tagosodes orizicolus, plaga del arroz y vector del virus de la hoja blanca. Se establecieron colonias del insecto en condiciones de invernadero usando plantas de arroz como alimento. Para el bioensayo, se desarrolló un sistema de alimentación in vitro para ninfas de tercer y cuarto estadío. Los insectos se alimentaron de soluciones de miel de abeja (1:48 vol/vol) y sacarosa (10 %) a través de membranas de Parafilm. Se observaron mortalidades del 10-15 % y 0-5 %, respectivamente, en ambas dietas. Los resultados fueron reproducibles en condiciones controladas de humedad y temperatura (18±0.1 °C de noche y 28±0.1 °C de día, 80 % H.R y a 12:12 fotoperíodo día:noche). Asimismo, se analizó la mortalidad natural de los insectos según su procedencia, sin embargo, no se observaron diferencias significativas en condiciones controladas. Finalmente, se elaboraron bioensayos para evaluar la toxicidad de una colección de cepas de Bt contra T. orizicolus. Se evaluó preliminarmente, una submuestra de 27 cepas de Bt en bioensayos burdos usando tres asadas como inóculo para 9 ml de dieta líquida. Posteriormente, las cepas que mostraron los mayores porcentajes de mortalidad se evaluaron en bioensayos usando esporas y cristales liofilizados (1 mg/ml). Como resultado, las cepas aisladas a partir de homópteros 26-O-to, 40-X-m, 43-S-d y 23-O-to mostraron mortalidades de 74, 96, 44 y 82 % respectivamente, mientras que las HD-137, HD-1 y Bti mostraron 19, 83 y 95 % de mortalidad. Los controles presentaron mortalidades de 0 y 10 % en los bioensayos. Este es el primer informe de un bioensayo para evaluar la toxicidad de cepas de Bt utilizando la especie T. orizicolus.

Ultrastructure of the wild rice Oryza grandiglumis (Gramineae) in Costa Rica

Oryza grandiglumis is a wild species of rice endemic to tropical America. This species was first found in 1998 in the wetlands of Caño Negro, located in the northern part of Costa Rica. Twenty five plants of O. grandiglumis were processed for scanning electron microscope. An ultrastructural description of the leaf blade, ligule, auricles, spikelet and caryopsis, with an emphasis on structures of taxonomic value. The leaf blade has a characteristic cuticular wax pattern, composed of dense rod-like structures, and is surrounded by papillae, zipper-like silica cells, abundant bulky prickle trichomes, and hooked trichomes. The blade's edge has three rows of hooked prickle trichomes of various sizes. The auricles wrapped the culm, with long attenuated trichomes at the edges; the base was surrounded by oblong cells. The ligule is a blunt membrane covered by short prickle trichomes. Spikelet morphology is characteristic of the Poaceae family, but the sterile lemmas were nearly as long as the fertile lemmas, and they have an unique crown-like structure of lignified spines between the rachilla and the fertile lemmas. Comparison with Brazilian specimens of O. grandiglumis revealed little differences in the ultrastructural characteristics.

El arroz silvestre Oryza grandiglumis es endémico de América. Se localiza en la zona norte de Costa Rica, principalmente en el humedal de Caño Negro y del Río Medio Queso. Es una planta vigorosa y grande. Su nombre deriva del gran tamaño de las lemas estériles (glumas). Presentamos una descripción ultraestructural de la lámina foliar, lígula, aurículas, espiguilla y cariópside, con énfasis en las estructuras de valor taxonómico, usando el microscopio electrónico de barrido. La lámina foliar se caracteriza por presentar un patrón de cera cuticular en forma de densos bastoncillos. Presenta estomas rodeados de papilas, células de sílice en forma crenada, varias formas de papilas de cera, distribuidas en forma muy regular, y tricomas espinosos abultados en la base y tricomas ganchudos. En el borde de la lámina hay tres hileras de tricomas espinosos ganchudos de diferente tamaño. Las aurículas son envolventes y los bordes presentan tricomas atenuados largos cubiertos en la base por células alargadas. La lígula es truncada y cubierta de tricomas espinosos pequeños. La morfología de la espiguilla es algo similar a las de las otras especies de la familia Poaceae, pero las lemas estériles son casi del mismo tamaño que las fértiles. Además se observó entre la raquilla y las lemas fértiles una corona de espinas lignificadas. Ultraestructuralmente, esta población es similar a las brasileñas.

Bacillus thuringiensis in caterpillars and associated materials collected from protected tropical forests in northwestern Costa Rica

Bacillus thuringiensis (Bt) synthesizes crystalline inclusions that are toxic to caterpillars (Lepidoptera) and other orders of invertebrates. Materials associated with 37 caterpillars from 16 species, collected while feeding on 15 different species of host plants in dry, cloud and rain forests located in the Area de Conservación Guanacaste in northwestern Costa Rica, were examined for the presence of Bt. From a total of 101 derived samples, 25 Bt isolates were cultured: 56% from host plant leaves, 8% from caterpillar guts and 36% from caterpillar fecal pellets. Bt was isolated from at least one sample in 38% of the systems constituted by the food plant, gut and fecal pellets corresponding to a single caterpillar. Four different morphologies of crystalline inclusions were observed, with bipyramidal and irregular crystal morphologies being the most prevalent.

Bacillus thuringiensis (Bt) sintetiza inclusiones cristalinas que resultan tóxicas para algunas larvas de lepidópteros y otros órdenes de invertebrados. Su presencia fue examinada en materiales asociados a 37 orugas de mariposas de 16 especies, las cuales fueron colectadas mientras se alimentaban en 15 especies diferentes de plantas hospederas en bosques secos, nubosos y húmedos localizados dentro del Área de Conservación Guanacaste (ACG) en el noroeste de Costa Rica. A partir de un total de 101 muestras se obtuvo 25 aislamientos de Bt: 56% a partir de material foliar de las plantas hospederas, 8% a partir del contenido intestinal de las larvas y 36% a partir de sus excrementos. Esta bacteria fue cultivada a partir de al menos uno de los 3 diferentes tipos de muestra asociados a una oruga particular (planta hospedera, intestino, excremento) en 38% de los casos posibles. En la colección de aislamientos obtenida se observaron cuatro morfologías de inclusiones cristalinas, siendo aquellas bipiramidales e irregulares las más prevalentes.

Characterization of a Bacillus thuringiensis strain collection isolated from diverse Costa Rican natural ecosystems

Costa Rican natural ecosystems are among the most diverse in the world. For this reason, we isolated strains of the entomopathogenic bacteria Bacillus thuringiensis (Bt ) to determine their diversity, distribution and abundance. A total of 146 Bt strains were obtained from environmental samples collected from diverse natural ecosystems and life zones of Costa Rica. We recovered Bt strains from 71%, 63%, 61% and 54% of soil samples, fresh leaves, other substrates and leaf litter respectively. Bt was isolated in 65% of the samples collected in the humid tropical forest in national parks (Braulio Carrillo, Gandoca Manzanillo, Sierpe, Hitoy Cerere, and Cahuita), and in 59% of the samples collected in the dry tropical forest (Parque Nacional Marino las Baulas, Palo Verde and Santa Rosa). In the very humid tropical forest (Tortuguero) Bt was isolated in 75% of the samples and in the very humid tropical forest transition perhumid (Carara) it was found in 69% of the samples. The strains exhibit a diverse number, size and morphology of parasporal inclusion bodies: irregular (47%), oval (20%), bipyramidal (3%), bipyramidal and cubic (1%), bipyramidal, oval and irregular (5%) and bipyramidal, oval and cubic crystals (2%). Strains isolated from Braulio Carrillo, Tortuguero and Cahuita, presented predominantly irregular crystals. On the other hand, more than 60% of the isolates from Térraba-Sierpe and Hitoy-Cerere had medium oval crystals. Strains from Gandoca-Manzanillo, Palo Verde and Carara presented mainly combinations of oval and irregular crystals. Nevertheless, the greatest diversity in crystal morphology was observed in those from Santa Rosa, Llanos del Río Medio Queso and Parque Marino las Baulas. Protein analyses of the crystal-spore preparations showed -endotoxin with diverse electrophoretic patterns, with molecular weights in the range of 20 to 160 kDa. Fifty six percent of the strains amplified with the cry2 primer, 54% with vip3, 20% with cry1...

Como los ecosistemas naturales de Costa Rica figuran entre los más diversos del mundo, se propuso aislar la bacteria entomopatógena Bacillus thuringiensis (Bt ) con el fin de conformar una colección de cepas y caracterizarlas molecularmente. Se obtuvieron 146 cepas a partir de muestras ambientales de diversas áreas protegidas, que incluían 9 de las 12 zonas de vida de Costa Rica. Se recobraron cepas del 71%, 63%, 61%y 54% de las muestras de suelo, hojas frescas, otros sustratos y hojarasca respectivamente. Se aisló Bt del 65% de las muestras del bosque tropical húmedo, un 59% de las muestras del bosque tropical seco. Del bosque tropical muy húmedo se aisló Bt del 75% de las muestras y finalmente del bosque tropical muy húmedo transición perhúmedo se encontró en el 69% de las muestras. Las cepas se caracterizaron según la morfología de los cuerpos paraesporales de inclusión, el peso molecular de las -endotoxinas y de genes cry,cyt y vip que contenían. Las cepas exhibieron cristales de diferente morfología, tamaño y número: irregulares, ovales, bipiramidales, cúbicos o mezclas de uno u otro. No se encontró correlación al comparar la forma de los cristales con el sitio de origen de la cepa. El análisis proteico de las mezclas de esporas y cristales mostró que las cepas contenían -endotoxinas de 20 a 160 kDa.El 66 por ciento de las cepas amplificaron con los imprimadores específicos para el gen cry2,54% con vip3, 20% con el cry1, 9% con el cry3-cry7 y 8% con el gen cry8. Los genes cry11 y cyt se encontraron en el 8%y 7% de las cepas respectivamente. Veinticuato cepas no amplificaron con los imprimadores utilizados por lo que podrían contener genes novedosos. Las cepas que contenían el gen cry1 se amplificaron posteriormente con imprimadores específicos para la subfamilia de dicho gen, obteniéndose 13 perfiles diferentes. En síntesis, la diversidad genética de las cepas sugiere que la colección tiene un gran potencial para el control de diferentes...

Effect of 2,4-D, hydric stress and light on indica rice (Oryza sativa) somatic embryogenesis

With the purpose of increasing the embryogenesis regeneration process in vitroplants obtained from somatic embryos of the indica rice variety CR-5272 (Oryza sativa L.), two independent experiments were performed. The first experiment consisted in the effect of combination of three concentrations of the gelling agent PhytagelTM (1.8, 2.4, and 3 gL-1) and four 2,4-D concentrations (2.26, 4.52, 6.78, and 9.05 m M) on the induction and subsequent regeneration of embryogenic calli. On the second experiment, the pre-regeneration phase was modified; calli were subjected to darkness or diffuse light conditions for one, two, and three weeks. In embryogenesis induction, 35% calligenesis was obtained using the MS culture medium supplemented with 6.78 m M of 2,4-D and 2.4 gL-1 PhytagelTM , whereas on the control treatment (MS medium supplemented with 9.05 m M of 2,4-D and 3 gL-1 PhytagelTM ) 24% calligenesis was obtained. In addition, regeneration percentages were improved (22% and 16% for calli induced with the above treatments, respectively). Furthermore, in light exposure experiments, the best result was obtained by exposing the embryogenic calli to darkness for one week in pre-regeneration, followed by direct light exposure during the regeneration phase

Ultrastructure of Oryza glumaepatula, a wild rice species endemic of tropical America

Oryza glumaepatula is a perennial wild rice species,endemic to tropical America, previously known as the Latin American race of Oryza rufipogon .In Costa Rica, it is found in the northern region of the country, mainly in the wetland of the Medio Queso River, Los Chiles, Alajuela. It is diploid, of AA type genome and because of its genetic relatedness to cultivated rice it is included in the O.sativa complex. We describe the ultrastructure of leaf blade, spikelet, ligule and auricles. Special emphasis is given to those traits of major taxonomic value for O.glumaepatula and to those characters that distinguish this species from O. rufipogon and O. sativa . O. glumaepatula has a leaf blade covered with tombstone-shaped, oblong and spheroid epicuticular wax papillae. It has diamond-shaped stomata surrounded by spherical papillae, rows of zipper-like silica cells, bulky prickle trichomes of ca .40 µm in length and small hirsute trichomes of ca. 32 µm in length.The central vein is covered with large,globular papillae of ca. 146 µm in length,a characteristic that distinguishes this species from O.rufipogon and O.sativa. The border of the leaf blade exhibits a row of even-sized bulky prickle trichomes of ca .42.5 µm in length.Auricles have attenuated trichomes of ca .5.5 mm in length on the edges and small bicellular trichomes of 120 µm in length on the surface.The ligule has a large number of short attenuated trichomes on its surface of 100 µm in length.These latter two traits have important taxonomic value since they were found in O.glumaepatula but not found in O.sativa or in O.rufipogon . The spikelet has the typical morphology of the Oryza genus. Fertile lemmas have abundant spines, a trait shared with O.rufipogon but not with O.sativa. The sterile lemmas are wing-shaped with serrated borders,a characteristic that distinguishes this species from O. rufipogon and O.sativa. All the ultrastructure characters observed in O.glumaepatula from Costa Rica are also common to the specimens from Brazil

O.glumaepatula es una especie de arroz silvestre perenne, endémica de América Tropical, conocida anteriormente como la O.rufipogon americana. En Costa Rica se le encuentra en la zona norte del país, principalmente en los humedales del río Medio Queso, Los Chiles, Alajuela. Es una especie diploide de genoma AA y por su cercanía genética con el arroz cultivado se le incluye en el complejo de O.sativa. El propósito de este trabajo es realizar una descripción ultraestructural de la morfología de la lámina foliar, espiguilla, lígula y aurículas. Se enfatizó en aquellas características de valor taxonómico para O.glumaepatula , destacando las características que la distinguen de O.rufipogon y O.sativa. Esta especie presenta la lámina foliar cubierta de papilas de cera en forma de lápida, alargadas y esferoides, tiene estomas romboidales rodeados de papilas esféricas, hileras de células de sílice de forma crenada, tricomas espinosos abultados de ca.40 m m y tricomas hirsutos pequeños de ca.32 m m. La vena central se encuentra cubierta de papilas globulares de ca.146 m m, característica que la distingue de O.rufipogon y O.sativa. El borde de la lámina presenta una hilera de tricomas espinosos abultados de tamaño homogéneo de ca. 42.5 m m. Las aurículas rizoides tienen tricomas atenuados largos en los bordes de ca. 5.5 mm y tricomas bicelulares en la superficie de ca.120 m m, esta última característica es de valor taxonómico. La lígula presenta en su superficie gran cantidad de tricomas atenuados cortos de ca.100 m m. La espiguilla presenta la morfología típica del género, las lemas fértiles tienen espinas abundantes y largas, característica que la comparte con O.rufipogon pero no con O.sativa. Las lemas estériles son aladas, de bordes dentados, característica que la distingue de O.rufipogon y de O.sativa. Las características ultraestructurales observadas en O.glumaepatula son comunes con la O.glumaepatula de Brasil

Genetic diversity of Costa Rican populations of the rice planthopper Tagosodes orizicolus (Homoptera: Delphacidae)

Tagosodes orizicolus (Homoptera: Delphacidae) is one of the main constraints of the rice production in the Neotropics. This planthopper produces severe damages as a phloem feeder, causes mechanical injury during oviposition and vectors the rice hoja blanca virus (RHBV). The main objective of this study was to determine the genetic diversity of T. orizicolus populations from three rice growing regions of Costa Rica, using RAPDs. Individuals from Guanacaste, Parrita, San Carlos and Cali-Colombia, as outgroup, were analyzed using the random primers. Phenetic relationships revealed that the Costa Rican populations were clearly separated from Cali-Colombia, sharing less than 25% similarity. Costa Rican populations were divided into two main branches separated at 30% similarity. The first branch included Guanacaste and San Carlos and the second displayed Parrita. In relation to similarity indexes within groups, the Guanacaste cluster showed the highest (over 50%) and Cali-Colombia was the most diverse (28%). The correspondence analysis confirmed the clusters of the phenogram and showed close interactions between the Parrita and San Carlos populations. The genetic separation observed could be the result of the geographic isolation among populations, but it could also be explained by the infection with the rickettsia Wolbachia pipientis. This bacterium causes cytoplasmic incompatibility in its host, which results in non-viable progeny when infected males mate with non-infected females, or when insects hosting different strains of Wolbachia mate. Then, a search for Wolbachia in previously described populations of T orizicolus was initiated. The presence of the bacteria was analyzed by PCR with 16S rDNA-specific primers for Wolbachia. The PCR analyses revealed infections of 86% in the population of San Carlos, 96% in Guanacaste, 37% in Parrita and 100% in Cali-Colombia. Crosses between individuals of T. orizicolus from Parrita and Guanacaste were performed for testing...

Phylogenetic position of the yeast-like symbiotes of Tagosodes orizicolus (Homoptera: Delphacidae) based on 18S ribosomal DNA partial sequences

Tagosodes orizicolus Muir (Homoptera: Delphacidae), the endemic delphacid species of tropical America carries yeast-like symbiotes (YLS) in the abdominal fat bodies and the ovarial tissues, like other rice planthoppers of Asia. These YLS are obligate symbiotes, which are transmitted transovarially, and maintain a mutualistic relationship with the insect host. This characteristic has made in vitro culture and classification of YLS rather difficult using conventional methods. Nevertheless, microorganisms of similar characteristics have been successfully classified by using molecular taxonomy. In the present work, the YLS of Tagosodes orizicolus (YLSTo) were purified on Percoll gradients, and specific segments of 18S rDNA were amplified by PCR, cloned and sequenced. Sequences were aligned by means of the CLUSTAL V (DNASTAR) program; phylogenetic trees were constructed with the Phylogeny Inference Package (PHYLIP), showing that YLSTo belong to the fungi class Pyrenomycetes, phylum Ascomycota. Similarities between 98% and 100% were observed among YLS of the rice delphacids Tagosodes orizicolus, Nilaparvata lugens, Laodelphax striatellus and Sogatella fur cifera, and between 89.8% and 90.8% when comparing the above to YLS of the aphid Hamiltonaphis styraci. These comparisons revealed that delphacid YLS are a highly conserved monophyletic group within the Pyrenomycetes and are closely related to Hypomyces chrysospermus.

Diversity of Bacillus thuringiensis strains isolated from coffee plantations infested with the coffee berry borer Hypothenemus hampei

The coffee berry borer Hypothenemus hampei Ferrari (Coleoptera: Scolytidae) was first reported infecting Costa Rican coffee plantations in the year 2000. Due to the impact that this plague has in the economy of the country, we were interested in seeking new alternatives for the biological control of H. hampei, based on the entomopathogenic bacteria Bacillus thuringiensis. A total of 202 B. thuringiensis isolates obtained from Costa Rican coffee plantations infested with H. hampei were analyzed through crystal morphology of the crystal inclusions and SDS-PAGE of 6-endotoxins, while 105 strains were further evaluated by PCR for the presence cry, cyt and vip genes. Most of the Bt strains showed diverse crystal morphologies: pleomorphic (35%), oval (37%), bipyramidal (3%), bipyramidal and oval (12%), bipyramidal, oval and pleomorphic (10%) and bipyramidal, oval and cubic (3%). The SDS-PAGE analyses of the crystal preparations showed five strains with delta-endotoxin from 20 to 40 kDa, six from 40 to 50 kDa, seven from 50 to 60 kDa, 19 from 60 to 70 kDa, 29 from 70 to 100 kDa and 39 from 100-145 kDa. PCR analyses demonstrated that the collection showed diverse cry genes profiles having several genes per strain: 78 strains contained the vip3 gene, 82 the cry2 gene, 45 the cry1 and 29 strains harbored cry3-cry7 genes. A total of 13 strains did not amplified with any of the cry primers used: cry1, cry2, cry3-7, cry5, cry11, cry12 and cry14. Forty-three different genetic profiles were found, mainly due to the combination of cry1A genes with other cry and vip genes. The genetic characterization of the collection provides opportunities for the selection of strains to be tested in bioassays against H. hampei and other insect pests of agricultural importance.

Expression of the rice hoja blanca virus (RHBV) non-structural protein 3 (NS3) in Escherichia coli and its in situ localization in RHBV-infected rice tissues

The non-structural NS3 protein gene from the rice hoja blanca virus (RHBV) was fused to the glutathione-S-transferase carboxilic end and expressed in Escherichia coli strain JM83. Large quantities of fusion protein were produced in insoluble form. The fusion protein was fractionated in SDS-PAGE and purified by electroelution, polyclonal antibodies were raised in rabbit and the antiserum was absorbed with bacterial crude extract. A band of similar size as that of NS3 protein was observed in Western blots using extracts from RHBV-infected rice plants. Immunoelectron microscopy with colloidal gold-labeled antibodies against NS3 protein and the viral nucleocapsid protein revealed in situ accumulation of NS3 protein in the cytoplasm but not in the viral inclusion bodies, vacuoles or chloroplasts of RHBV-infected plants, following the same pattern of distribution as the RHBV nucleocapsid protein.

Relación de los cultivos modificados genéticamente con el ambiente y la salud de la población costarricense / Relationship of genetically modified crops with the environment and health of the Costa Rican human population

Genetic engineering and the food derived from genetically modified crops (GMCs) have been the center of debate worldwide, as has occurred historically with the advent of new technologies. Questions are derived from the potential impact of GMCs to the environment and the safety of the products to the consumers. In relation to the first inquiry, practice has been oriented to a case-by-case-study, according to the own characteristics of the GMC, in order to minimize its impact in the environment. Scientific studies in diverse latitudes of the world have demonstrated that GMCs in the market showed no adverse effects related to this issue. In relation to food derived from the GMCs, rigorous evaluation protocols have been developed and approved by FAO and WHO to guarantee the innocuousness of these products. Up to the moment, no contraindications for human health have been pointed out for the products that are available today in the market. In the particular case of Costa Rica, the country has established since the 90s a regulatory biosafety framework for the management of the GMCs, safeguarding the biodiversity of the country and the health of consumers. At the same time the country has made significant public and private investments in the field that allowed the country to obtain a leading position in biosafety in the region and genetic engineering research at national research centers. Any attempt to restrict or prohibit these activities in the country, will put in risk the previously described investment, will affect the generation of new knowledge for decision making and the leadership in the field, preventing the benefits derived from this promising technology.

Factores de riesgo osociados al inicio de relaciones sexuales en adolescentes mujeres estudiantes en La Paz-Bolivia / Rick factors for imitation of sexual intercourse among high school female student in La Paz Bolivia

Objetivo: identificar factores de riesgo asociados al inicio de la ctividad sexual en adolescentes mujeres estudiantes de secundaria en Paz, Bolivia. Métodos: se realizó un estudio transversal mediante una encuesta nóninsa aplicada a estudiantes mujeres de los dos últimos años de ecundaria de colegios públicos y privados de la ciudad de La Paz. Resultados: se analizaron 275 encuestas (o = 275). La edad 1 promedio fue de 17 ± 0.8 años. Los factores de riesgo identificados fueron consumo de sustancias (alcohol y tabaco), relación de paréja y asistencia a reuniones sociales y discotecas. Los factores de protección fueron actividad deportiva y abstinencia respecto al consumo de sustancias. No demostró influir sohre esta conducta sexual: condición del establecimiento educativo, estabilidad del entorno familiar, embarazo de la madre durante su adolesceocia, reuniones con familiares y la educación sexual. Aceptaron haber iniciado su actividad sexual 15,6 porciento del total con una edad promedio de inicio de 16,6±1 años. Conclusiones: ci consumo de sustancias y la preferencia por actividades sociales están fuertemente asociados al inicio de la actividad sexual durante la adolescencia