Targeting of genomic and negative-sense strands of viral RNA contributes to antiviral resistance mediated by artificial miRNAs and promotes the emergence of complex viral populations.

Technology based on artificial small RNAs, including artificial microRNAs (amiRNAs), exploits natural RNA silencing mechanisms to achieve silencing of endogenous genes or pathogens. This technology has been successfully employed to generate resistance against different eukaryotic viruses. However, information about viral RNA molecules effectively targeted by these small RNAs is rather conflicting, and factors contributing to the selection of virus mutants escaping the antiviral activity of virus-specific small RNAs have not been studied in detail. In this work, we transformed Nicotiana benthamiana plants with amiRNA constructs designed against the potyvirus plum pox virus (PPV), a positive-sense RNA virus, and obtained lines highly resistant to PPV infection and others showing partial resistance. These lines have allowed us to verify that amiRNA directed against genomic RNA is more efficient than amiRNA targeting its complementary strand. However, we also provide evidence that the negative-sense RNA strand is cleaved by the amiRNA-guided RNA silencing machinery. Our results show that the selection pressure posed by the amiRNA action on both viral RNA strands causes an evolutionary explosion that results in the emergence of a broad range of virus variants, which can further expand in the presence, and even in the absence, of antiviral challenges.

Inyección intrarticular única ecoguiada de ácido hialurónico en la coxartrosis sintomática: estudio retrospectivo de la eficacia de dos presentaciones / Single eco-guided intra-articular injection of hyaluronic acid in symptomatic coxarthrosis: retrospective study of the efficacy of two presentations

Introducción: La viscosuplementación ecoguiada con ácido hialurónico en la coxartrosis sintomática se ha extendido como tratamiento seguro con eficacia demostrada, aunque con falta de consenso en su uso como práctica habitual. Pocos estudios han comparado la eficacia de dos productos de inyección única. Objetivo: Evaluar la eficacia en pacientes infiltrados con dos ácidos hialurónicos de inyección única comparando Adant One® (A) a seis meses con Hyalone® (H) anual.Material y método: Estudio observacional retrospectivo sobre cohorte de pacientes con coxartrosis sintomática, tratados mediante viscosuplementación intrarticular ecoguiada de cadera con dos tipos de inyección única de ácido hialurónico. Su eficacia fue evaluada de acuerdo con las escalas WOMAC y EVA a los 6 y 12 meses. Resultados: Fueron tratados 144 pacientes con una dosis única de A y 84 con H. A los 6 meses aquellos tratados con A mostraron mejoras en relación con disminución del dolor en la EVA (p < 0,001) y en el WOMAC dolor (p = 0,003), así como en WOMAC global (p = 0,027). No hubo cambios en WOMAC rigidez y función. A los 12 meses los tratados con H mostraron mejorías en los parámetros EVA (p < 0,001) y WOMAC global (p = 0,010) y en todas sus dimensiones de manera significativa. Conclusiones: Una inyección única de H anual fue más efectiva para mejorar el dolor y la funcionalidad de la cadera con artrosis a 1 año comparado con A semestral. Es posible establecer protocolos anuales de viscosuplementación para la artrosis de cadera con ácido hialurónico usando H.(AU)

Introduction: Ultrasound-guided viscosupplementation with hyaluronic acid in symptomatic hip osteoarthritis is widely used as a safe treatment with proven efficacy, although there is a lack of consensus on its use as routine practice. Few studies have compared the efficacy of two single injection products. Objetive: To evaluate the efficacy in infiltrated patients with two single injection hyaluronic acids comparing Adant One® (A) at six months with annual Hyalone® (H).Material and method: Restrospective observational study on a cohort of patients with symptomatic hip osteoarthritis, treated by ultrasound-guided intra-articular viscossuplementation with two types of single injection of hyaluronic acid. Its efficacy was evaluated according to the WOMAC and VAS scales at 6 and 12 months. Results: 144 patients were treated with a single dose of A and 84 with H. At 6 months, those treated with A showed improvements in relation to pain reduction in the VAS (p < 0.001) and in the WOMAC pain (p = 0.003), as well as in global WOMAC (p = 0.027). There were no changes in WOMAC stiffness and function. At 12 months, those treated with H showed significant improvements in the VAS (p < 0.001) and global WOMAC (p = 0.010) parameters and in all their dimensions. Conclusions: A single injection of annual H was more effective in improving pain and function of the hip with osteoarthritis at 1 year compared to A at 6 months. It is possible to establish annual viscossuplementation protocols for hip osteoarthritis with hyaluronic acid using H.(AU)

Formation of Multicolor Nanogels Based on Cationic Polyfluorenes and Poly(methyl vinyl ether-alt-maleic monoethyl ester): Potential Use as pH-Responsive Fluorescent Drug Carriers.

In this study, we employed the copolymer poly(methyl vinyl ether-alt-maleic monoethyl ester) (PMVEMA-Es) and three fluorene-based cationic conjugated polyelectrolytes to develop fluorescent nanoparticles with emission in the blue, green and red spectral regions. The size, Zeta Potential, polydispersity, morphology, time-stability and fluorescent properties of these nanoparticles were characterized, as well as the nature of the interaction between both PMVEMA-Es and fluorescent polyelectrolytes. Because PMVEMA-Es contains a carboxylic acid group in its structure, the effects of pH and ionic strength on the nanoparticles were also evaluated, finding that the size is responsive to pH and ionic strength, largely swelling at physiological pH and returning to their initial size at acidic pHs. Thus, the developed fluorescent nanoparticles can be categorized as pH-sensitive fluorescent nanogels, since they possess the properties of both pH-responsive hydrogels and nanoparticulate systems. Doxorubicin (DOX) was used as a model drug to show the capacity of the blue-emitting nanogels to hold drugs in acidic media and release them at physiological pH, from changes in the fluorescence properties of both nanoparticles and DOX. In addition, preliminary studies by super-resolution confocal microscopy were performed, regarding their potential use as image probes.

Home-made enzymatic premix and Illumina sequencing allow for one-step Gibson assembly and verification of virus infectious clones.

An unprecedented number of viruses have been discovered by leveraging advances in high-throughput sequencing. Infectious clone technology is a universal approach that facilitates the study of biology and role in disease of viruses. In recent years homology-based cloning methods such as Gibson assembly have been used to generate virus infectious clones. We detail herein the preparation of home-made cloning materials for Gibson assembly. The home-made materials were used in one-step generation of the infectious cDNA clone of a plant RNA virus into a T-DNA binary vector. The clone was verified by a single Illumina reaction and a de novo read assembly approach that required no primer walking, custom primers or reference sequences. Clone infectivity was finally confirmed by Agrobacterium-mediated delivery to host plants. We anticipate that the convenient home-made materials, one-step cloning and Illumina verification strategies described herein will accelerate characterization of viruses and their role in disease development.

Sterol isomerase HYDRA1 interacts with RNA silencing suppressor P1b and restricts potyviral infection.

Plants use RNA silencing as a strong defensive barrier against virus challenges, and viruses counteract this defence by using RNA silencing suppressors (RSSs). With the objective of identifying host factors helping either the plant or the virus in this interaction, we have performed a yeast two-hybrid screen using P1b, the RSS protein of the ipomovirus Cucumber vein yellowing virus (CVYV, family Potyviridae), as a bait. The C-8 sterol isomerase HYDRA1 (HYD1), an enzyme involved in isoprenoid biosynthesis and cell membrane biology, and required for RNA silencing, was isolated in this screen. The interaction between CVYV P1b and HYD1 was confirmed in planta by Bimolecular Fluorescence Complementation assays. We demonstrated that HYD1 negatively impacts the accumulation of CVYV P1b in an agroinfiltration assay. Moreover, expression of HYD1 inhibited the infection of the potyvirus Plum pox virus, especially when antiviral RNA silencing was boosted by high temperature or by coexpression of homologous sequences. Our results reinforce previous evidence highlighting the relevance of particular composition and structure of cellular membranes for RNA silencing and viral infection. We report a new interaction of an RSS protein from the Potyviridae family with a member of the isoprenoid biosynthetic pathway.

Improvement of Body Satisfaction in Older People: An Experimental Study.

Aging typically manifests itself in a variety of physical and cognitive alterations and challenges that are not always easily accepted. Feeling dissatisfied with these changes can also affect the mood and self-esteem of older people causing body image problems. The present study focuses on body satisfaction in Spanish older people (176 participants; M and SD = 64.03 ± 1 8.06; age range 50 to over 75) by employing experimental research to test whether psychosocial interventions may have a positive impact. Our aims are threefold: (1) To describe the body satisfaction of older people considering intervening variables, such as age, gender, having a stable partner, time of the year, and place of residence; (2) to compare body satisfaction improvement in older people participating in a specific body satisfaction program designed for this purpose versus a non-specific program run by the Spanish Red Cross; and (3) to examine the relationship between age, gender, having a stable partner, time of the year, place of residence, body satisfaction and participating in the experimental condition. The IMAGINA specific body image program yielded a significant improvement in body satisfaction when compared with the non-specific program in both men and women regardless of marital status and in some age groups: 50 to 54 years old, 60 to 64 years old, and 65 to 69. Male participants, as well as singles, were more satisfied with their bodies, and the contrary was true for divorced and separated. The IMAGINA program was particularly useful in participants with more body image problems. As shown, the pressure to fit beauty standards and related problems do not go away with age, a fact that is embodied and experienced differently in men and women.

Truncation of a P1 leader proteinase facilitates potyvirus replication in a non-permissive host.

The Potyviridae family is a major group of plant viruses that includes c. 200 species, most of which have narrow host ranges. The potyvirid P1 leader proteinase self-cleaves from the remainder of the viral polyprotein and shows large sequence variability linked to host adaptation. P1 proteins can be classified as Type A or Type B on the basis, amongst other things, of their dependence or not on a host factor to develop their protease activity. In this work, we studied Type A proteases from the Potyviridae family, characterizing their host factor requirements. Our in vitro cleavage analyses of potyvirid P1 proteases showed that the N-terminal domain is relevant for host factor interaction and suggested that the C-terminal domain is also involved. In the absence of plant factors, the N-terminal end of Plum pox virus P1 antagonizes protease self-processing. We performed extended deletion mutagenesis analysis to define the N-terminal antagonistic domain of P1. In viral infections, removal of the P1 protease antagonistic domain led to a gain-of-function phenotype, strongly increasing local infection in a non-permissive host. Altogether, our results shed new insights into the adaptation and evolution of potyvirids.

Multiple T-DNA Delivery to Plants Using Novel Mini Binary Vectors with Compatible Replication Origins.

Improved plants are necessary to meet human needs. Agrobacterium-mediated transformation is the most common method used to rewire plant capabilities. For plant gene delivery, DNA constructs are assembled into binary T-DNA vectors that rely on broad host range origins for bacterial replication. Here we present pLX vectors, a set of mini binary T-DNA plasmids suitable for Type IIS restriction endonuclease- and overlap-based assembly methods. pLX vectors include replicons from compatible broad host range plasmids. Simultaneous usage of pBBR1- and RK2-based pLX vectors in a two-plasmid/one-Agrobacterium strain strategy allowed multigene delivery to plants. Adoption of pLX vectors will facilitate routine plant transformations and targeted mutagenesis, as well as complex part and circuit characterization.

Piomiositis del obturador en un niño coincidiendo con faringoamigdalitis estreptocócica / Obturator pyomyositis in a child in association with group A streptococcal pharyngitis

Se presenta el caso de un niño de ocho años que desarrolla una piomiositis de los músculos obturador interno y externo, coincidiendo con una faringoamigdalitis estreptocócica. Inicialmente presenta solo dolor en miembro inferior izquierdo, siendo diagnosticado de contractura del bíceps femoral. Pocos días más tarde comienza con odinofagia, exantema cutáneo escarlatiniforme, fiebre y exudado amigdalar. Llama la atención la persistencia de dolor intenso en la pierna izquierda, dolor lumbar bajo y signo de Lassègue positivo, por lo que se realiza una resonancia magnética en la que se observa la piomiositis. Se realiza una revisión de los casos de piomiositis descritos recientemente, observándose un aumento de la incidencia en nuestro entorno. Se compara la clínica con dichos casos para intentar identificar signos clínicos que puedan ayudar a un diagnóstico precoz del proceso (AU)

We present the case of an eight-year-old child who developed a pyomyositis of the internal and external obturator muscles and streptococcal tonsillitis simultaneously. Initially, he only presented pain in the lower left limb and he was diagnosed a contracture of the biceps femoris muscle. A few days after, he began with odynophagia, cutaneous exanthema and fever with tonsillar exudate. However, the pain in the left leg persisted, lower lumbar pain and Lassègue sign appeared, so we underwent a magnetic resonance imaging demonstrating the pyomyositis. We reviewed recently described cases of pyomyositis, and we observed an increase of their incidence in our environment. A comparison is made with other case reviews to identify the clinical symptoms that could help in diagnosing the condition early (AU)

Assorted Processing of Synthetic Trans-Acting siRNAs and Its Activity in Antiviral Resistance.

The use of syn-tasiRNAs has been proposed as an RNA interference technique alternative to those previously described: hairpin based, virus induced gene silencing or artificial miRNAs. In this study we engineered the TAS1c locus to impair Plum pox virus (PPV) infection by replacing the five native siRNAs with two 210-bp fragments from the CP and the 3´NCR regions of the PPV genome. Deep sequencing analysis of the small RNA species produced by both constructs in planta has shown that phased processing of the syn-tasiRNAs is construct-specific. While in syn-tasiR-CP construct the processing was as predicted 21-nt phased in register with miR173-guided cleavage, the processing of syn-tasiR-3NCR is far from what was expected. A 22-nt species from the miR173-guided cleavage was a guide of two series of phased small RNAs, one of them in an exact 21-nt register, and the other one in a mixed of 21-/22-nt frame. In addition, both constructs produced abundant PPV-derived small RNAs in the absence of miR173 as a consequence of a strong sense post-transcriptional gene silencing induction. The antiviral effect of both constructs was also evaluated in the presence or absence of miR173 and showed that the impairment of PPV infection was not significantly higher when miR173 was present. The results show that syn-tasiRNAs processing depends on construct-specific factors that should be further studied before the so-called MIGS (miRNA-induced gene silencing) technology can be used reliably.

The Potyviridae P1a leader protease contributes to host range specificity.

The P1a protein of the ipomovirus Cucumber vein yellowing virus is one of the self-cleavage serine proteases present in Potyviridae family members. P1a is located at the N-terminal end of the viral polyprotein, and is closely related to potyviral P1 protease. For its proteolytic activity, P1a requires a still unknown host factor; this might be linked to involvement in host specificity. Here we built a series of constructs and chimeric viruses to help elucidate the role of P1a cleavage in host range definition. We demonstrate that host-dependent separation of P1a from the remainder of the polyprotein is essential for suppressing RNA silencing defenses and for efficient viral infection. These findings support the role of viral proteases as important determinants in host adaptation.

Neofobia y otros trastornos restrictivos alimentarios en la infancia y consumo de frutas y verduras: revisión / Neophobia and other food restrictive disorders in childhood and intake of fruits and vegetables: a review

Objetivo: El objetivo de la presente revisión es conocer las características de los niños que presentan problemas alimentarios evitativo/restrictivos en la infancia incidiendo especialmente en los que presentan neofobia alimentaria así como su relación con el consumo de frutas y verduras. Métodos: Se ha realizado una extensa búsqueda de publicaciones científicas utilizando las palabras clave «food neophobia», «children», «picky eating», «fussy eating», «feeding problems» y «food preferences» en bases de datos electrónicas especializadas seleccionando finalmente 61 artículos para la revisión. Resultados: La neofobia alimentaria tiene un gran impacto y una repercusión directa en el consumo de diferentes alimentos y, especialmente, en la ingesta de frutas y verduras, confirmando que los niños neofóbicos presentan dietas menos saludables que sus compañeros neofílicos. La revisión muestra también que los problemas alimentarios de neofobia alimentaria y alimentación «caprichosa» no están claramente diferenciados, y que las consecuencias nutricionales son prácticamente idénticas. Conclusiones: La neofobia se asocia a un problema alimentario que implica un bajo consumo de frutas y verduras en la infancia y, por tanto, debe ser tomado en consideración desde la perspectiva de la nutrición comunitaria. También hay que señalar que el papel de los progenitores es fundamental en el mantenimiento o disminución de la neofobia (AU)

Objective: The aim of this review is to identify the characteristics of children that present avoidant/restrictive feeding problems in infancy focusing specially on those that present food neophobia as well as its relationship with the intake of fruits and vegetables. Methods: An extensive search of scientific publications using the keywords «food neophobia», «children», «picky eating», «fussy eating», «feeding problems» and «food preferences» in specialised electronic databases has been carried out, finally selecting 61 articles for the review. Results: Food neophobia has an impact and direct repercussion on consumption of different foods, particularly in the intake of fruits and vegetables, confirming that neophobic children have less healthy diets than their neophilic peers. The review also shows that both food neophobia and picky/fussy eating are not clearly differentiated eating problems, and that the nutritional consequences are virtually identical. Conclusions: Food neophobia is a feeding problem that implies a low intake of fruits and vegetables in infancy and therefore, it should be taken into account from the standpoint of the community nutrition. It should also be noted that the role of parents is fundamental in the maintenance or reduction of neophobia (AU)

Rapid fluorescent reporter quantification by leaf disc analysis and its application in plant-virus studies.

BACKGROUND: Fluorescent proteins are extraordinary tools for biology studies due to their versatility; they are used extensively to improve comprehension of plant-microbe interactions. The viral infection process can easily be tracked and imaged in a plant with fluorescent protein-tagged viruses. In plants, fluorescent protein genes are among the most commonly used reporters in transient RNA silencing and heterologous protein expression assays. Fluorescence intensity is used to quantify fluorescent protein accumulation by image analysis or spectroscopy of protein extracts; however, these methods might not be suitable for medium- to large-scale comparisons. RESULTS: We report that laser scanners, used routinely in proteomic studies, are suitable for quantitative imaging of plant leaves that express different fluorescent protein pairs. We developed a microtiter plate fluorescence spectroscopy method for direct quantitative comparison of fluorescent protein accumulation in intact leaf discs. We used this technique to measure a fluorescent reporter in a transient RNA silencing suppression assay, and also to monitor early amplification dynamics of a fluorescent protein-labeled potyvirus. CONCLUSIONS: Laser scanners allow dual-color fluorescence imaging of leaf samples, which might not be acquired in standard stereomicroscope devices. Fluorescence microtiter plate analysis of intact leaf discs can be used for rapid, accurate quantitative comparison of fluorescent protein accumulation.

p,p-Dihydroxydihydrostilbenophanes related to antimitotic combretastatins. Conformational analysis and its relationship to tubulin inhibition.

The structures of a new family of macrocyclic analogues of combretastatins B combining oxygenated substituents on the phenyl rings and indole rings are described. The effects of the stereochemistry, of the length of the spacer linking both aryl groups, and of the decoration of the macrocycles on the kinematics of the system have been studied by means of NMR studies at several temperatures and in different solvents combined with theoretical studies including Monte Carlo conformational searches and molecular dynamics simulations at different temperatures. The new indole macrocycles provide a more rigid view of this kind of macrocycles than that previously held. The tubulin polymerization activity of this new class of macrocycles has been assayed and analyzed.

Virus-induced gene silencing in transgenic plants: transgene silencing and reactivation associate with two patterns of transgene body methylation.

We used bisulfite sequencing to study the methylation of a viral transgene whose expression was silenced upon plum pox virus infection of the transgenic plant and its subsequent recovery as a consequence of so-called virus-induced gene silencing (VIGS). VIGS was associated with a general increase in the accumulation of small RNAs corresponding to the coding region of the viral transgene. After VIGS, the transgene promoter was not methylated and the coding region showed uneven methylation, with the 5' end being mostly unmethylated in the recovered tissue or mainly methylated at CG sites in regenerated silenced plants. The methylation increased towards the 3' end, which showed dense methylation in all three contexts (CG, CHG and CHH). This methylation pattern and the corresponding silenced status were maintained after plant regeneration from recovered silenced tissue and did not spread into the promoter region, but were not inherited in the sexual offspring. Instead, a new pattern of methylation was observed in the progeny plants consisting of disappearance of the CHH methylation, similar CHG methylation at the 3' end, and an overall increase in CG methylation in the 5' end. The latter epigenetic state was inherited over several generations and did not correlate with transgene silencing and hence virus resistance. These results suggest that the widespread CG methylation pattern found in body gene bodies located in euchromatic regions of plant genomes may reflect an older silencing event, and most likely these genes are no longer silenced.

The hypervariable amino-terminus of P1 protease modulates potyviral replication and host defense responses.

The replication of many RNA viruses involves the translation of polyproteins, whose processing by endopeptidases is a critical step for the release of functional subunits. P1 is the first protease encoded in plant potyvirus genomes; once activated by an as-yet-unknown host factor, it acts in cis on its own C-terminal end, hydrolyzing the P1-HCPro junction. Earlier research suggests that P1 cooperates with HCPro to inhibit host RNA silencing defenses. Using Plum pox virus as a model, we show that although P1 does not have a major direct role in RNA silencing suppression, it can indeed modulate HCPro function by its self-cleavage activity. To study P1 protease regulation, we used bioinformatic analysis and in vitro activity experiments to map the core C-terminal catalytic domain. We present evidence that the hypervariable region that precedes the protease domain is predicted as intrinsically disordered, and that it behaves as a negative regulator of P1 proteolytic activity in in vitro cleavage assays. In viral infections, removal of the P1 protease antagonistic regulator is associated with greater symptom severity, induction of salicylate-dependent pathogenesis-related proteins, and reduced viral loads. We suggest that fine modulation of a viral protease activity has evolved to keep viral amplification below host-detrimental levels, and thus to maintain higher long-term replicative capacity.

Conducta antisocial: conexión con emociones positivas y variables predictoras / Antisocial behavior: Connection with positive emotions and predictor variables

El estudio tuvo dos objetivos: 1) Explorar las relaciones que existen entre la conducta antisocial (autoevaluada y evaluada por los padres) y variables como empatía, inteligencia emocional, autoestima, y dimensiones de personalidad (neuroticismo, extraversión, apertura, amabilidad, responsabilidad), e 2) Identificar variables que predicen la conducta antisocial. La muestra fue de 3.026 participantes de 12 a 18 años. Con un diseño descriptivo y correlacional se administraron 6 instrumentos de evaluación. Los resultados mostraron que los adolescentes y jóvenes de ambos sexos, con altas puntuaciones en conducta antisocial tenían significativamente: 1) menor capacidad de empatía (para ponerse en el punto de vista de otro); 2) menor capacidad de regulación emocional (control de estados emocionales); 3) menor nivel de amabilidad (cordialidad, altruismo); 4) menor nivel de responsabilidad (voluntad para lograr objetivos académicos); 5) mayor nivel de neuroticismo (inestabilidad emocional, sentimientos negativos); y 6) mayor nivel de extraversión (sociabilidad, asertividad, excitación). Las relaciones entre conducta antisocial y autoestima no fueron concluyentes. Bajo nivel de empatía, de amabilidad, de responsabilidad, alto nivel de neuroticismo, de extraversión, y mayor edad predijeron la conducta antisocial. La discusión enfatiza la importancia de implementar programas que fomenten el desarrollo socioemocional (comunicación, empatía, emociones, conducta prosocial…) para prevenir la conducta antisocial (AU)

The study had two goals: 1) To explore the relations between antisocial behavior (self-assessed and parent-assessed) and variables such as empathy, emotional intelligence, self-esteem, and personality dimensions (neuroticism, extraversion, openness, agreeableness, responsibility); and 2) To identify variables that predict antisocial behavior. The sample is made up of 3,026 participants aged between 12 and 18 years. Using a descriptive and correlational design, 6 assessment instruments were administered. The results showed that adolescents young people of both sexes, with high scores in antisocial behavior had significantly: 1) less capacity for empathy (take on the other’s viewpoint); 2) less capacity for emotional regulation (control of moods); 3) lower level of agreeableness (cordiality, altruism); 4) lower level of responsibility (will to achieve academic goals); 5) higher level of neuroticism (emotional instability, negative feelings); and 6) higher level of extraversion (sociability, assertiveness, excitement). The relations between antisocial behavior and self-esteem were inconclusive. Low levels of empathy, agreeableness, and responsibility, and high levels of neuroticism, extraversion, and being older predicted antisocial behavior. The discussion emphasizes the importance of implementing programs that promote socio-emotional development (communication, empathy, emotions, prosocialbehavior…) to prevent antisocial behavior (AU)

Diverse amino acid changes at specific positions in the N-terminal region of the coat protein allow Plum pox virus to adapt to new hosts.

Plum pox virus (PPV)-D and PPV-R are two isolates from strain D of PPV that differ in host specificity. Previous analyses of chimeras originating from PPV-R and PPV-D suggested that the N terminus of the coat protein (CP) includes host-specific pathogenicity determinants. Here, these determinants were mapped precisely by analyzing the infectivity in herbaceous and woody species of chimeras containing a fragment of the 3' region of PPV-D (including the region coding for the CP) in a PPV-R backbone. These chimeras were not infectious in Prunus persica, but systemically infected Nicotiana clevelandii and N. benthamiana when specific amino acids were modified or deleted in a short 30-amino-acid region of the N terminus of the CP. Most of these mutations did not reduce PPV fitness in Prunus spp. although others impaired systemic infection in this host. We propose a model in which the N terminus of the CP, highly relevant for virus systemic movement, is targeted by a host defense mechanism in Nicotiana spp. Mutations in this short region allow PPV to overcome the defense response in this host but can compromise the efficiency of PPV systemic movement in other hosts such as Prunus spp.

La corporalidad de los adolescentes en las redes sociales / The body image in adolescents in social network

Las Redes Sociales (RS) influyen en la corporalidad de los adolecentes y en otras variables psicológicas a través de las publicaciones virtuales. Uno de los fenómenos más extendidos es el sexting que se ha incrementado en adolescentes y es objeto de seria preocupación. Objetivos: a) Conocer el uso de RS; b) Analizar la frecuencia de publicaciones virtuales estéticas frente a eróticas en adolescentes en función del género. Instrumentos: CIV-RS. Cuestionario de Imagen Virtual de las Redes Sociales(Maganto y Peris, 2011). Participantes: 100 adolescentes de ambos sexos (13-15años). Resultados: El uso de las RS está extendido, sin apenas diferencias de sexo. La imagen virtual es preferentemente estética, pero en un porcentaje preocupante publican imágenes con contenido sensual, erótico y provocador. Además, los adolescentes publican fotografías sin consentimiento y temen arrepentirse de algunas fotografías publicadas. Conclusiones: Es un reto conocer el uso y los riesgos de las RS, a fin de desarrollar programas preventivos (AU)

Body image and other psychological variables have been influenced by social networks. One of the most widespread phenomena is the sexting that has increased in adolescents and is of serious concern. Objectives: a) know the use of RS; b) Analyze the frequency of aesthetic versus erotic virtual publications in adolescents according to sex. Assessment instruments: Virtual image of the social network questionnaire (Maganto y Peris, 2011). Participants: 100 adolescents’ boys and girls from 13 to 15 years. Results: The use of the social network is widespread, not just statistical differences of sex. The virtual image is mostly aesthetic, but they published a high percentage of erotic, sensual and provocative photography. In addition, adolescents publish photographs without consent, and probably in the future they repent of the photographs that have been published. Conclusions: Is a challenge to know the use and risks of social networks in order to develop preventive programmes (AU)