Two new species of Daidalotarsonemus (Acari: Prostigmata: Tarsonemidae) from Brazil

International audienceTwo new tarsonemid species, Daidalotarsonemus esalqi sp. n. and Daidalotarsonemus savanicus sp. n., found on both native and crop plants in Brazil are described herein, based on adult females. Biological aspects of these species are briefly discussed. Individuals of Daidalotarsonemus savanicus sp. n. have been misidentified as Daidalotarsonemus tessellatus De Leon in previous reports of this species from Brazil. A key is provided to distinguish females of the Daidalotarsonemus species known to occur in Brazil

Poly(Anhydride) Nanoparticles Act as Active Th1 Adjuvants through Toll-Like Receptor Exploitation

The mechanisms that underlie the potent Th1-adjuvant capacity of poly(methyl vinyl ether-co-maleic anhydride) nanoparticles (NPs) were investigated. Traditionally, polymer NPs have been considered delivery systems that promote a closer interaction between antigen and antigen-presenting cells (APCs). Our results revealed that poly(anhydride) NPs also act as agonists of various Toll-like receptors (TLRs) (TLR2, -4, and -5), triggering a Th1-profile cytokine release (gamma interferon [IFN- ], 478 pg/ml versus 39.6 pg/ml from negative control; interleukin-12 [IL-12], 40 pg/ml versus 7.2 pg/ml from negative control) and, after incubation with dendritic cells, inducing a 2.5- to 3.5-fold increase of CD54 and CD86 costimulatory molecule expression. Furthermore, in vivo studies suggest that NPs actively elicit a CD8 T-cell response. Immunization with empty NPs resulted in a significant delay in the mean survival date (from day 7 until day 23 postchallenge) and a protection level of 30% after challenge against a lethal dose of Salmonella enterica serovar Enteritidis. Taken together, our results provide a better understanding of how NPs act as active Th1 adjuvants in immunoprophylaxis and immunotherapy through TLR exploitation

Humoral immune response in hens naturally infected with Salmonella Enteritidis against outer membrane proteins and other surface structural antigens

A simple procedure for obtaining surface exposed antigens of Salmonella Enteritidis is described. A heat treatment of whole bacteria in saline solution induced the release of small membrane vesicles containing outer membrane components as well as surface appendage components, such as fimbriae and flagellin. The characterization of the structural components of this extract, called HE, was established by SDS-PAGE and immunoblotting using polyclonal and monoclonal specific antibodies. Five major groups of proteins were identified: flagellin, porins, OmpA, SEF21 and SEF14 fimbriae. The immunogenicity of these proteins was studied by immunoblotting with serum samples from naturally infected hens. Flagellin, porins, OmpA, SEF14 and SEF21 fimbriae were immunogenic in the S. Enteritidis infected hens (frequency of reactants: 47.3, 97.3, 64.7, 50.0 and 60.8%, respectively); porins also reacted with sera from non infected hens (66.7%). The immunogenicity of these antigens in infected birds provide promise that they may serve as components of an effective subcellular vaccine for poultry salmonellosis

Resistance to DNA Damaging agents produced invasive phenotype of rat glioma cells-characterization of a new in vivo model

Chemoresistance and invasion properties are severe limitations to efficient glioma therapy. Therefore, development of glioma in vivo models that more accurately resemble the situation observed in patients emerges. Previously, we established RC6 rat glioma cell line resistant to DNA damaging agents including antiglioma approved therapies such as 3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and temozolomide (TMZ). Herein, we evaluated the invasiveness of RC6 cells in vitro and in a new orthotopic animal model. For comparison, we used C6 cells from which RC6 cells originated. Differences in cell growth properties were assessed by real-time cell analyzer. Cells’ invasive potential in vitro was studied in fluorescently labeled gelatin and by formation of multicellular spheroids in hydrogel. For animal studies, fluorescently labeled cells were inoculated into adult male Wistar rat brains. Consecutive coronal and sagittal brain sections were analyzed 10 and 25 days post-inoculation, while rats’ behavior was recorded during three days in the open field test starting from 25th day post-inoculation. We demonstrated that development of chemoresistance induced invasive phenotype of RC6 cells with significant behavioral impediments implying usefulness of orthotopic RC6 glioma allograft in preclinical studies for the examination of new approaches to counteract both chemoresistance and invasion of glioma cells

The role of posttraumatic stress and posttraumatic growth on online information use in breast cancer survivors

ObjectiveChanges perceived as both positive (eg, posttraumatic growth [PTG]) and negative (eg, posttraumatic stress symptoms [PTSS]) have been associated with intensive Internet use among breast cancer survivors. In this multicenter study, we analyzed the role of PTG and PTSS on the amount of time spent looking for online cancer information, its content, and its psychological impact. MethodsPosttraumatic stress symptoms and PTG were assessed in 182 breast cancer survivors by using the Post-traumatic Stress Disorder Checklist and Post-traumatic Growth Inventory questionnaires. Subjects also completed a questionnaire about their behavior when looking for online illness-related information (ie, time spent, type of contents, and psychological impact). ResultsPosttraumatic stress symptoms positively correlated with the amount of time spent looking for cancer-related information, including both medical and psychosocial content. By contrast, PTG showed no relationships with the amount of time, but with a predominant search for cancer-related psychosocial information. The psychological impact of online information was associated with participants' levels of PTG and/or PTSS. Whereas PTG was related to a decrease of women's hope, PTSS was linked to the perception of being less conscious or inadequately informed about the illness, thereby increasing feelings of distress. ConclusionsPosttraumatic stress symptoms and PTG show relationships with the amount of time spent online, the type of information accessed online, and the psychological impact of Internet use. Health professionals should prescribe online information according to the psychological response to cancer. There is a need for professional-led online resources to provide patients with timely information as well as support sites to facilitate psychological adjustment

Profiling for run-time checking of computational properties and performance debugging in logic programs

Although several profiling techniques for identifying performance bottlenecks in logic programs have been developed, they are generally not automatic and in most cases they do not provide enough information for identifying the root causes of such bottlenecks. This complicates using their results for guiding performance improvement. We present a profiling method and tool that provides such explanations. Our profiler associates cost centers to certain program elements and can measure different types of resource-related properties that affect performance, preserving the precedence of cost centers in the cali graph. It includes an automatic method for detecting procedures that are performance bottlenecks. The profiling tool has been integrated in a previously developed run-time checking framework to allow verification of certain properties when they cannot be verified statically. The approach allows checking global computational properties which require complex instrumentation tracking information about previous execution states, such as, e.g., that the execution time accumulated by a given procedure is not greater than a given bound. We have built a prototype implementation, integrated it in the Ciao/CiaoPP system and successfully applied it to performance improvement, automatic optimization (e.g., resource-aware specialization of programs), run-time checking, and debugging of global computational properties (e.g., resource usage) in Prolog programs

Cómo aprendemos los docentes de universidad. Implicaciones para la formación docente

Este artículo se basa en un proyecto de investigación coordinado sobre cómo aprenden los docentes, sus implicaciones educativas y los retos para afrontar el cambio social. Desde un posicionamiento basado en la investigación inclusiva y la utilización de métodos visuales se crearon 65 cartografías sobre los escenarios o contextos de aprendizaje de docentes de educación infantil, primaria, secundaria y superior (en este caso los investigadores del proyecto). También, se compartieron las explicaciones y reflexiones sobre las cartografías realizadas dando cuenta de los tránsitos y experiencias de aprendizaje. En este artículo, presentamos los resultados y las conclusiones sobre cómo aprendemos los docentes de educación superior, centrados en los autores de este texto. Destacamos las posibilidades de la experiencia cartográfica para la investigación educativa y la consideración de que el aprendizaje del profesorado no solo tiene lugar en contextos formales e institucionales, sino a lo largo y ancho de la vida. Elaboramos conclusiones sobre las características del aprendizaje del profesorado actual y sobre la importancia de tener en cuenta su carácter contextual, biográfico, corporeizado y socioafectivo en la formación inicial y permanente de los docentes. También avanzamos algunas implicaciones para repensar la formación docente al considerar las relaciones entre las experiencias de vida y el aprendizaje, la importancia de conectar las instituciones educativas con la sociedad, la reflexión sobre la práctica educativa y los principales desafíos educativos. Todo ello con la finalidad de promover la transformación de los centros educativos en instituciones de aprendizaje con sentido

Development and characterization of a microfluidic model of the tumour microenvironment

The physical microenvironment of tumours is characterized by heterotypic cell interactions and physiological gradients of nutrients, waste products and oxygen. This tumour microenvironment has a major impact on the biology of cancer cells and their response to chemotherapeutic agents. Despite this, most in vitro cancer research still relies primarily on cells grown in 2D and in isolation in nutrient- and oxygen-rich conditions. Here, a microfluidic device is presented that is easy to use and enables modelling and study of the tumour microenvironment in real-time. The versatility of this microfluidic platform allows for different aspects of the microenvironment to be monitored and dissected. This is exemplified here by real-time profiling of oxygen and glucose concentrations inside the device as well as effects on cell proliferation and growth, ROS generation and apoptosis. Heterotypic cell interactions were also studied. The device provides a live ‘window’ into the microenvironment and could be used to study cancer cells for which it is difficult to generate tumour spheroids. Another major application of the device is the study of effects of the microenvironment on cellular drug responses. Some data is presented for this indicating the device’s potential to enable more physiological in vitro drug screening

Root ABA and H+-ATPase are key players in the root and shoot growth-promoting action of humic acids

Although the ability of humic (HA) and fulvic acids (FA) to improve plant growth has been demonstrated, knowledge about the mechanisms responsible for the direct effects of HA and FA on the promotion of plant growth is scarce and fragmentary. Our study investigated the causal role of both root PM H+-ATPase activity and ABA in the SHA-promoting action on both root and shoot growth. The involvement of these processes in the regulation of shoot cytokinin concentration and activity was also studied. Our aim was to integrate such plant responses for providing new insights to the current model on the mode of action of HA for promoting root and shoot growth. Experiments employing specific inhibitors and using Cucumis sativus L. plants show that both the root PM H+-ATPase activity and root ABA play a crucial role in the root growth-promoting action of SHA. With regard to the HA-promoting effects on shoot growth, two pathways of events triggered by the interaction of SHA with plant roots are essential for the increase in root PM H+-ATPase activity-which also mediates an increase in cytokinin concentration and action in the shoot-and the ABA-mediated increase in hydraulic conductivity (Lp(r))