Caracterizacion molecular de aislamientos de sweepovirus que infectan Ipomoea batatas (L.) Lam. y estudio de sinergismo con el sweet potato chlorotic stunt virus (SPCSV).

Los sweepovirus forman un grupo dentro del genero Begomovirus que se caracterizan por infectar solo a camote, los cuales comunmente causan infeccion asintomatica, pasando inadvertidos, por lo que su prevalencia y distribucion es desconocida en algunas regiones del mundo. Las infecciones multiples son sinergicamente con otros virus. En el presente estudio, se obtuvieron 48 secuencias a partir de fragmentos de PCR usando cebadores universales para sweepovirus de un total de 239 muestras de camote mantenidas en el banco de germoplasma del Centro Internacional de la Papa (CIP). Se seleccionaron y caracterizaron los genomas completos de seis aislamientos de sweepovirus: Peru-6, Mexico-31, Cuba-5, San Vicente, Peru-10 y Jamaica-12, utilizando PCR en sentido inverso para los cuatro primeros aislados y por la polimerasa Phi29 para los ultimos dos. La comparacion completa de los genomas confirmo que los seis virus eran bastante diferentes entre si con un 89 % de identidad a excepcion de Jamaica-12 y Cuba-5 (91 %), y San Vicente y Peru-10 (93 %). Se realizo una evaluacion del sinergismo de cada uno de ellos con el aislamiento M2-47 del SPCSV durante un periodo de 10 semanas. Esta se realizo mediante la expresion de sintomas en plantas de camote variedad "Huachano" con infecciones simples (sweepovirus) y dobles (sweepovirus + SPCSV). La deteccion de los sweepovirus se realizo mediante la prueba de hibridacion de acidos nucleicos y por RT-PCR en tiempo real el SPCSV. Se encontro que existe un sinergismo con una magnitud considerablemente variable entre los titulos de los diferente aislados de sweepovirus y que en la mayoria de los casos no se asocio con sintomas claros. La informacion obtenida en este estudio puede contribuir al diagnostico e identificacion de sweepovirus y el aumento de sus titulos presente en algunas interacciones sinergicas sugiere que pueden tener un impacto en el rendimiento y esto debe ser una prioridad para estudio futuros

Desarrollo y aplicacion de PCR multiple para la deteccion simultanea de tres virus de ADN en camote (Ipomoea batatas L.)

El virus colusivo del camote (SPCV, genero Cavemovirus), el virus del aclaramiento de venas del camote (SPVC, genero Solendovirus) y el virus del enrollamiento de hojas del camote (SPLCV, genero Begomovirus) son virus con genoma de ADN, presentes en el camote en infecciones virales simples o multliples. La identificacion y deteccion de estos virus es complicada, ya que con frecuencia son asintomaticos y estan en concentraciones bajas en las plantas de camote. Se desarrollo una PCR multiple (mPCR) con el objetivo de lograr la deteccion simultanea de SPVC, SPVCV y SPLCV (y Begomovirus relacionados); para ellos se seleccionaron cebadores especificos para SPCV y SPVCV, y se utilizaron cebadores degenerados para Begomovirus (desarrollados por Li et al. 2004). Para la optimizacion de parametros se usaron plantas de camote con infecciones simples y mixtas. Se optimizo la concentracion de cebadores (0,1-0, 3uM), MgCl2 (2,5-8,0mM), dNTPs (0.2-0.8 mM), Taq-polimerasa (2-4U), parametros en el termociclador (temperatura de hibridacion de 48-62 oC y el numero de ciclos de 29-35), y la cantidad de acidos nucleidos (50-300 ng). Para validar le mPCR se uso plantas de camote de una coleccion de germplasma in vitro que estaban infectados con los virus en estudio y fueron confirmados por clonacion y secuenciamiento de las amplificaciones obtenidas. Los pares de cebadores especificos seleccionados para cada virus pudieron amplificar fragmentos de ADN en tamanos esperados, a una concentracion final de 0.16 uM para cebadores de SPCV y SPVCV, y 0.2uM para SPLCV. Ademas la concentracion de ADN adecuada esta entre 50-100 ng, con 30 ciclos termicos y 53 oC de temperatura de hibridacion. Este ensayo demostro ser simple, sensible y confiable para el diagnostico de rutina de SPCV, SPVCV y SPLCV (y Begomovirus relacionados). El ensayo de mPCR sera util para programas de cuarentena, como un metodos rapido y rentable para un gran numero de muestras

Attentional Bias for Cues Signaling Punishment and Reward in Adolescents:Cross-Sectional and Prognostic Associations with Symptoms of Anxiety and Behavioral Disorders

Heightened reward sensitivity has been proposed as a risk factor for developing behavioral disorders whereas heightened punishment sensitivity has been related to the development of anxiety disorders in youth. Combining a cross-sectional (n = 696, mean age = 16.14) and prospective (n = 598, mean age = 20.20) approach, this study tested the hypotheses that an attentional bias for punishing cues is involved in the development of anxiety disorders and an attentional bias for rewarding cues in the development of behavioral disorders. A spatial orientation task was used to examine the relation between an attentional bias for punishing cues and an attentional bias for rewarding cues with anxiety and behavioral problems in a subsample of a large prospective population cohort study. Our study indicates that attentional biases to general cues of punishment and reward do not seem to be important risk factors for the development of anxiety or behavioral problems respectively. It might be that attentional biases play a role in the maintenance of psychological problems. This remains open for future research

Behavioral problems in anxious youth:Cross-sectional and prospective associations with reinforcement sensitivity and parental rejection

A subsample of children and young people (CYP) with anxiety disorders presents with comorbid behavioral problems. These CYP have greater impairment in daily life, profit less from current treatments, and have an increased risk for continued mental problems. We investigated two potential explanations for these comorbid behavioral problems. First, high punishment sensitivity (PS) may lead to a strong inclination to experience threat, which may not only elicit anxiety but also defensive behavioral problems. Second, behavioral problems may arise from high reward sensitivity (RS), when rewards are not obtained. Behavioral problems may subsequently elicit parental rejection, thereby fueling anxiety. We used a cross-sectional (age = 16.1, N = 61) and prospective (age = 22.2, N = 91) approach to test the relationship between PS/RS and comorbid behavioral problems. Participants were a subsample of highly anxious CYP from a large prospective cohort study. PS/RS were indexed by a spatial orientation task. We also investigated the prospective association between behavioral problems and anxiety at 6-year follow-up, and the proposed mediation by parental rejection. PS and RS showed no cross-sectional or prospective relationships with comorbid behavioral problems in highly anxious CYP. Yet, behavioral problems in adolescence showed a small prospective relationship with anxiety in young adulthood, but this was not mediated nor moderated by parental rejection. No evidence was found for PS/RS being involved in comorbid behavioral problems in anxious CYP. Findings point to comorbid behavioral problems as potential factor contributing to the further increase of anxiety

Induction of somatic embryogenesis in recalcitrant sweetpotato (Ipomoea batatas L.) cultivars

Genetic transformation is considered as one of the most promising options for improvement of crop traits. Current transformation methods for sweetpotato depend on plant regeneration through organogenesis or somatic embryogenesis. Somatic embryogenesis and plant regeneration at a high frequency has been  restricted to a few sweetpotato varieties. Three auxins namely: 2,4-dichlorophenoxyacetic acid (2,4-D),  4-fluoroamphetamine (4-FA) and 4,5-trichlorophenoxyacetic acid (2,4,5-T) were investigated in this study for enhancing somatic embryogenesis from various plant organs of recalcitrant African sweetpotato cultivars.  2,4-D was found to be the best (p . 0.05) for induction of embryogenic callus. Cultivar Bwanjule had the highest  (20.2%) embryogenic callus frequency among the five African cultivars tested. The highest number of plants in this study was regenerated from the non-African cultivar variety Jonathan on media supplemented with 0.2 mg Zeatin. The emergence of roots from callus of recalcitrant Ugandan cultivars and the comparable high embryogenic responses in this work demonstrate the potential for regenerating plants from African  cultivars that have not been regenerated before. The regeneration of roots in this work could be useful for the initiation of root cultures. The most important application of this work is in genetic transformation of sweet potato, particularly for improvement of resistance to weevils.Key words: Embryogenesis, plant growth regulators, plant regeneration, Ipomoea batatas

Cognitive-behavior therapy for children and adolescents with anxiety disorders:A meta-analysis of secondary outcomes

Anxiety-focused cognitive-behavioral therapy (CBT) effectively reduces anxiety in children and adolescents. An important remaining question is to what extent anxiety-focused CBT also affects broader outcome domains. Additionally, it remains unclear whether parental involvement in treatment may have impact on domains other than anxiety. A meta-analysis (nstudies = 42, nparticipants = 3239) of the effects of CBT and the moderating role of parental involvement was conducted on the following major secondary outcomes: depressive symptoms, externalizing behaviors, general functioning, and social competence. Randomized controlled trials were included when having a waitlist or active control condition, a youth sample (aged<19) with a primary anxiety disorder diagnosis receiving anxiety-focused CBT and reported secondary outcomes. Controlled effect sizes (Cohen's d) were calculated employing random effect models. CBT had a large effect on general functioning (-1.25[-1.59;0.90], nstudies = 17), a small to moderate effect on depressive symptoms (-0.31[-0.41;-0.22], nstudies = 31) and a small effect on externalizing behaviors (-0.23[-0.38;-0.09], nstudies = 12) from pre-to post-treatment. Effects remained or even further improved at follow-up. Social competence only improved at follow-up (nstudies = 6). Concluding, anxiety-focused CBT has a positive effect on broader outcome domains than just anxiety. Higher parental involvement seemed to have beneficial effects at follow-up, with improvements in general functioning and comorbid symptoms

Extreme salinity as a challenge to grow potatoes under Mars-like soil conditions: targeting promising genotypes.

One of the future challenges to produce food in a Mars environment will be the optimization of resources through the potential use of the Martian substratum for growing crops as a part of bioregenerative food systems. In vitro plantlets from 65 potato genotypes were rooted in peat-pellets substratum and transplanted in pots filled with Mars-like soil from La Joya desert in Southern Peru. The Mars-like soil was characterized by extreme salinity (an electric conductivity of 19.3 and 52.6 dS m−1 under 1 : 1 and saturation extract of the soil solution, respectively) and plants grown in it were under sub-optimum physiological status indicated by average maximum stomatal conductance <50 mmol H2O m−2 s−1 even after irrigation. 40% of the genotypes survived and yielded (0.3–5.2 g tuber plant−1) where CIP.397099.4, CIP.396311.1 and CIP.390478.9 were targeted as promising materials with 9.3, 8.9 and 5.8% of fresh tuber yield in relation to the control conditions. A combination of appropriate genotypes and soil management will be crucial to withstand extreme salinity, a problem also important in agriculture on Earth that requires more detailed follow-up studies