Suscetibilidade de Spodoptera Frugiperda a isolados geográficos de um vírus de poliedrose nuclear

O presente trabalho objetivou verificar a suscetibilidade de larvas de segundo ínstar de Spodoptera frugiperda (Smith, 1797) a sete isolados geográficos de um vírus de poliedrose nuclear (VPN), conduzindo-se sete bioensaios no Laboratório de Patologia de Insetos da Embrapa-Centro Nacional de Pesquisa de Soja, Londrina. Para cada isolado preparou-se dieta artificial contendo 0, 2x10³, 4x10³, 8x10³, 16x10³, 32x10³ e 64x10³ corpos poliédricos de inclusão (CPI)/mL. Cada dose foi oferecida às larvas em copos de plástico de 50 mL, sob condições controladas (temperatura: 26±2ºC; umidade relativa: 60±10%; fotófase:14 horas). A análise (Probits) realizada sobre o somatório de larvas mortas (contadas, diariamente, do quinto ao décimo quarto dia após a inoculação) mostrou, com base na ausência de sobreposição das amplitudes dos intervalos de confiança das concentrações letais médias (CL50), que: o isolado de Sertaneja, PR (5.631 CPI/mL), foi o mais virulento; o da Guatemala (11.520 CPI/mL) equivaleu aos de Ponta Grossa, PR (14.184 CPI/mL), Argentina (15.891 CPI/mL) e Alabama, EUA (17.558 CPI/mL), mas foi superior aos isolados de Louisiana, EUA (19.325 CPI/mL) e Sete Lagoas, MG (25.310 CPI/mL). A variação do tempo letal médio, de 8,3 a 10 dias, não foi significativa em relação aos isolados.

TWEAK-FN14 signaling induces lysosomal degradation of a cIAP1-TRAF2 complex to sensitize tumor cells to TNFalpha.

Synthetic inhibitor of apoptosis (IAP) antagonists induce degradation of IAP proteins such as cellular IAP1 (cIAP1), activate nuclear factor kappaB (NF-kappaB) signaling, and sensitize cells to tumor necrosis factor alpha (TNFalpha). The physiological relevance of these discoveries to cIAP1 function remains undetermined. We show that upon ligand binding, the TNF superfamily receptor FN14 recruits a cIAP1-Tnf receptor-associated factor 2 (TRAF2) complex. Unlike IAP antagonists that cause rapid proteasomal degradation of cIAP1, signaling by FN14 promotes the lysosomal degradation of cIAP1-TRAF2 in a cIAP1-dependent manner. TNF-like weak inducer of apoptosis (TWEAK)/FN14 signaling nevertheless promotes the same noncanonical NF-kappaB signaling elicited by IAP antagonists and, in sensitive cells, the same autocrine TNFalpha-induced death occurs. TWEAK-induced loss of the cIAP1-TRAF2 complex sensitizes immortalized and minimally passaged tumor cells to TNFalpha-induced death, whereas primary cells remain resistant. Conversely, cIAP1-TRAF2 complex overexpression limits FN14 signaling and protects tumor cells from TWEAK-induced TNFalpha sensitization. Lysosomal degradation of cIAP1-TRAF2 by TWEAK/FN14 therefore critically alters the balance of life/death signals emanating from TNF-R1 in immortalized cells.

Lack of original antigenic sin in recall CD8(+) T cell responses.

In the real world, mice and men are not immunologically naive, having been exposed to numerous antigenic challenges. Prior infections sometimes negatively impact the response to a subsequent infection. This can occur in serial infections with pathogens sharing cross-reactive Ags. At the T cell level it has been proposed that preformed memory T cells, which cross-react with low avidity to epitopes presented in subsequent infections, dampen the response of high-avidity T cells. We investigated this with a series of related MHC class-I restricted Ags expressed by bacterial and viral pathogens. In all cases, we find that high-avidity CD8(+) T cell precursors, either naive or memory, massively expand in secondary cross-reactive infections to dominate the response over low-avidity memory T cells. This holds true even when >10% of the CD8(+) T cell compartment consists of memory T cells that cross-react weakly with the rechallenge ligand. Occasionally, memory cells generated by low-avidity stimulation in a primary infection recognize a cross-reactive epitope with high avidity and contribute positively to the response to a second infection. Taken together, our data show that the phenomenon of original antigenic sin does not occur in all heterologous infections.

Hábitos higiénico-dietéticos respecto al consumo de alimentos ricos en yodo durante el primer trimestre de la gestación

Objetivo: Conocer los hábitos higiénico-dietéticos de las mujeres embarazadas respecto al consumo de alimentos ricos en yodo durante el primer trimestre de la gestación. Material y método: Estudio observacional, descriptivo, transversal y multicéntrico. Se estudiaron las mujeres embarazadas en el primer trimestre de la gestación que acudieron a la consulta de control del embarazo del programa de atención a la salud sexual y reproductiva (ASSIR) de la Región Sanitaria del Ámbito Centro del Instituto Catalán de la Salud durante el año 2006. Para la recogida de datos se utilizó un cuestionario que cumplimentó la matrona en una entrevista individual en la primera visita de control de embarazo. Resultados: Se recogieron 823 cuestionarios cumplimentados. El 6% (50) de las gestantes no consumía pescado y el 83% (683) lo hacía menos de cuatro veces por semana. El 17% (138) no consumía leche y el 39% (324) bebía un vaso al día. El 42% (342) de las gestantes utilizaba sal yodada para la preparación y condimentación de los alimentos, frente al 50% (412) que no la empleaba. El 22% (184) de las gestantes tomaba algún tipo de suplemento de yodo, y el 18% (148) de la muestra manifestó ser fumadora. Conclusiones: Las mujeres embarazadas de nuestro ámbito de estudio tienen un consumo reducido de alimentos ricos en yodo. Además, tanto el consumo de sal yodada como la utilización de suplementos que contengan yodo durante el embarazo resultan también insuficientes.

Insights from insects about adaptive social information use.

Copying others can greatly improve individual fitness and is fundamental for the organisation of societies. Yet in some situations it is better to ignore social information and either explore the world individually or use personal information obtained through prior experience. Insects provide excellent models to study the strategic use of social information, but insights from recent research have rarely been viewed in the light of social learning strategies. Here we discuss how insects tailor their reliance on social information to those circumstances for which it is most beneficial, and suggest that insects and vertebrates use similar information-use strategies. We highlight future research avenues, including the use of molecular tools to study the genetic and genomic basis of social information use.

Accuracy of out-of-field dose calculation of tomotherapy and cyberknife treatment planning systems: A dosimetric study.

PURPOSE: Late toxicities such as second cancer induction become more important as treatment outcome improves. Often the dose distribution calculated with a commercial treatment planning system (TPS) is used to estimate radiation carcinogenesis for the radiotherapy patient. However, for locations beyond the treatment field borders, the accuracy is not well known. The aim of this study was to perform detailed out-of-field-measurements for a typical radiotherapy treatment plan administered with a Cyberknife and a Tomotherapy machine and to compare the measurements to the predictions of the TPS. MATERIALS AND METHODS: Individually calibrated thermoluminescent dosimeters were used to measure absorbed dose in an anthropomorphic phantom at 184 locations. The measured dose distributions from 6 MV intensity-modulated treatment beams for CyberKnife and TomoTherapy machines were compared to the dose calculations from the TPS. RESULTS: The TPS are underestimating the dose far away from the target volume. Quantitatively the Cyberknife underestimates the dose at 40cm from the PTV border by a factor of 60, the Tomotherapy TPS by a factor of two. If a 50% dose uncertainty is accepted, the Cyberknife TPS can predict doses down to approximately 10 mGy/treatment Gy, the Tomotherapy-TPS down to 0.75 mGy/treatment Gy. The Cyberknife TPS can then be used up to 10cm from the PTV border the Tomotherapy up to 35cm. CONCLUSIONS: We determined that the Cyberknife and Tomotherapy TPS underestimate substantially the doses far away from the treated volume. It is recommended not to use out-of-field doses from the Cyberknife TPS for applications like modeling of second cancer induction. The Tomotherapy TPS can be used up to 35cm from the PTV border (for a 390 cm(3) large PTV).

Cyberadministration : un tremplin pour les pays émergents : illustration à travers un exemple, constats et perspectives

Nous assistons actuellement à une diffusion, à l'échelle planétaire, des Technologies de l'Information et de la Communication (TIC) même si elle se fait à des rythmes différents selon les nations (voire entre les régions d'un même pays) créant ainsi un fossé dit « numérique », en sus des multiples inégalités déjà présentes. Cette révolution informatique et technologique engendre de nombreux changements dans les rapports sociaux et permet de nombreuses applications destinées à simplifier la vie quotidienne de tout un chacun. Amine Bekkouche se penche sur la problématique de la cyberadministration comme conséquence importante des TIC, à l'instar du commerce électronique. Il présente, d'abord, une synthèse des principaux concepts de la cyberadministration ainsi qu'un panorama de la situation mondiale en ce domaine. Par la suite, il appréhende la cyberadministration dans la perspective des pays émergents, notamment, à travers l'illustration d'un pays en développement représentatif. Il propose alors des solutions concrètes qui prennent comme point de départ le secteur éducatif pour permettre une « alphabétisation informatique » de la société afin de contribuer justement à réduire le fossé numérique. Il élargit, ensuite, ces propositions à d'autres domaines et formule des recommandations facilitant leur mise en oeuvre. Il conclut, enfin, sur des perspectives qui pourraient constituer autant de pistes de recherches futures et permettre l'élaboration de projets de développement, à travers l'appropriation de ces TIC, pour améliorer la condition de l'administré, et plus globalement, du citoyen. - We are currently witnessing a distribution of Information and Communication Technologies (ICT) on a global scale. Yet, this distribution is carried out in different rhythms within each nation (and even among regions in a given country), which creates a "digital" gap, in addition to multiple inequalities already present. This computing and technological revolution engenders many changes in social relationships and permits numerous applications that are destined to simplify our lives. Amine Bekkouche takes a closer look at the issue of e-government as an important consequence of ICTs, following the example of electronic commerce. First, he presents a synthesis of the main concepts in e- government as well as a panoramic view of the global situation in this domain. Subsequently, he studies e-government in view of emerging countries, in particular through the illustration of a country in representative development. Then, he offers concrete solutions, which take the education sector as their starting point, to allow for a "computed digitalisation" of society that contribute to reduce the digital gap. Thereafter, he broadens these proposals to other domains and formulates recommendations that help their implementation. Finally, he concludes with perspectives that may constitute further research tracks and enable the elaboration of development projects, through the appropriation of ICTs, in order to improve the condition of the administered, and more generally, that of the citizen.

Contagem de células somáticas e produção de leite em vacas holandesas de alta produção

A mastite bovina pode ser clínica, com sinais visíveis, e subclínica, diagnosticada pela contagem das células somáticas. As perdas econômicas causadas pela mastite subclínica devem ser quantificadas para atender à demanda nacional de produtos lácteos. O objetivo deste trabalho foi verificar se as perdas na produção de leite, pelo aumento do número de células somáticas, são proporcionais ou independentes do nível de produção. Foram utilizadas 7.756 observações, colhidas mensalmente de um único rebanho, de setembro de 2000 a junho de 2002. A curva de lactação foi modelada pela função gama incompleta, e os efeitos de ordem de lactação, época do parto, ocorrência de doenças no periparto e escore de condição corporal ao parto também foram considerados. A contagem de células somáticas foi incluída nesse modelo como fator multiplicativo, representando perdas relativas, e como fator aditivo, representando perdas absolutas. A escolha do melhor modelo foi baseada no critério de informação de Schwarz (BIC). As perdas são absolutas, evidentes a partir de 14.270 células/mL e para cada aumento de uma unidade na escala do logaritmo natural a partir desse valor, estimam-se perdas de 184 e 869 g/dia para vacas primíparas e multíparas, respectivamente.

Prothese totale du genou aujourd'hui: que dire a nos patients? [Total knee arthroplasty today: what should we tell our patients?]

Total knee arthroplasty (TKA) remains the preferred treatment for patients with invalidating osteoarthritis. It allows these patients to find once again a satisfactory quality of life. These results are reflected by the increasing number of interventions performed each year and in always younger patients. The objective of this review of the scientific literature was to determine the long-term quantitatively and qualitatively results of TKA and determine the parameters which could influence the long-term outcome. There does not seem to be any clear arguments in favor of one type of implant or surgical technique. One also notices that TKA in females and older patients seem to have longer lifespan, estimated to approximately 15 years. The most frequent complication remains aseptic loosening followed by infections.