Electrochemical detection of Toxocara canis excretory-secretory antigens in children from rural communities in Esmeraldas Province, Ecuador: association between active infection and high eosinophilia.

BACKGROUND: The diagnosis of active Toxocara canis infections in humans is challenging. Larval stages of T. canis do not replicate in human tissues and disease may result from infection with a single T. canis larva. Recently, we developed a nanobody-based electrochemical magnetosensor assay with superior sensitivity to detect T. canis excretory-secretory (TES) antigens. Here, we evaluate the performance of the assay in children from an Ecuadorian birth cohort that followed children to five years of age. METHODS: Samples were selected based on the presence of peripheral blood eosinophilia and relative eosinophil counts. The samples were analyzed by the nanobody-based electrochemical magnetosensor assay, which utilizes a bivalent biotinylated nanobody as capturing agent on the surface of streptavidin pre-coated paramagnetic beads. Detection was performed by a different nanobody chemically labelled with horseradish peroxidase. RESULTS: Of 87 samples tested, 33 (38%) scored positive for TES antigen recognition by the electrochemical magnetosensor assay. The average concentration of TES antigen in serum was 2.1 ng/ml (SD = 1.1). The positive result in the electrochemical assay was associated with eosinophilia > 19% (P = 0.001). Parasitological data were available for 57 samples. There was no significant association between positivity by the electrochemical assay and the presence of other soil-transmitted helminth infections. CONCLUSIONS: Our nanobody-based electrochemical assay provides highly sensitive quantification of TES antigens in serum and has potential as a valuable tool for the diagnosis of active human toxocariasis

Large stabilization effects by intramolecular Beryllium bonds in Ortho-Benzene derivatives

Intramolecular interactions are shown to be key for favoring a given structure in systems with a variety of conformers. In ortho-substituted benzene derivatives including a beryllium moiety, beryllium bonds provide very large stabilizations with respect to non-bound conformers and enthalpy differences above one hundred kJ·mol(−1) are found in the most favorable cases, especially if the newly formed rings are five or six-membered heterocycles. These values are in general significantly larger than hydrogen bonds in 1,2-dihidroxybenzene. Conformers stabilized by a beryllium bond exhibit the typical features of this non-covalent interaction, such as the presence of a bond critical point according to the topology of the electron density, positive Laplacian values, significant geometrical distortions and strong interaction energies between the donor and acceptor quantified by using the Natural Bond Orbital approach. An isodesmic reaction scheme is used as a tool to measure the strength of the beryllium bond in these systems in terms of isodesmic energies (analogous to binding energies), interaction energies and deformation energies. This approach shows that a huge amount of energy is spent on deforming the donor–acceptor pairs to form the new rings

The transcriptional repressor Bcl6 promotes pre-TCR induced differentiation to CD4+CD8+ thymocyte and attenuates Notch1 activation

Pre-TCR signal transduction is required for developing thymocytes to differentiate from CD4-CD8- double negative (DN) to CD4+CD8+ double positive (DP) cell. Notch signalling is required for T-cell fate specification and must be maintained throughout β-selection, but inappropriate Notch activation in DN4 and DP cells is oncogenic. Here, we show that pre-TCR signalling leads to increased expression of the transcriptional repressor Bcl6 and that Bcl6 is required for differentiation to DP. Conditional deletion of Bcl6 from thymocytes reduced pre-TCR-induced differentiation to DP cell, disrupted expansion and enrichment of icTCRβ+ cells within the DN population and increased DN4 cell death. It also increased Notch1 activation and Notch-mediated transcription in the DP population. Thus, Bcl6 is required in thymocyte development for efficient differentiation from DN3 to DP cell and to attenuate Notch1 activation in DP cells. Given the importance of inappropriate NOTCH1 signalling in T-ALL, and the involvement of Bcl6 in other types of leukaemia, this study is important to our understanding of T-ALL

Effect of cystamine on sperm and antioxidant parameters of ram semen stored at 4 °C for 50 hours

Physical and chemical changes caused by oxidative stress in the spermatozoa membrane can reduce spermatozoa function and even lead to death. Cystamine (NH2-CH2-CH2-SH, β-mercaptoethylamine) is a natural substance that modulates the endocrine and metabolic status of animals. This substance has antioxidant and anti-apoptotic effects by inducing intracellular cysteine accumulation. Cystamine is used to treat many diseases despite its many side effects. Sheep semen is sensitive to the stressful condition of chilling storage, which restricts semen storage for artificial insemination in commercial herds. The effect of cystamine on spermatogenesis is not yet fully understood. The present study aimed to investigate the effect of cysteamine addition to the sheep sperm extender during cooling storage on semen quality parameters. Sperm samples were collected from six Edilbayevskaya rams (2 and 3 years old, 70-85 kg). The samples were diluted by extender and supplemented with different concentrations of cysteamine (0, 1, 2, 5, and 10 mM) and cooled to 4ºC for 50 h. Motility parameters, membrane integrity, viability, lipid peroxidation, and mitochondrial activity of cooled semen were evaluated at 0, 25, and 50 h of cooling storage. Although cysteamine failed to affect semen quality at start time (0 hrs), extender supplementation with cysteamine improved sperm total motility, progressive motility, and mitochondrial membrane potential during storage periods (P≤0.01). Moreover, using 1 and 2 mM cysteamine functionally and viably improved (P≤0.01) sperm membrane compared to other treatments. Antioxidant potential (AOP), lipid peroxidation (LPO), and total glutathione (tGSH) (except AOP at 50 h) were significantly different after semen storage at 4 °C. Therefore, levels of AOP and tGSH were significantly increased by using cysteamine. Cysteamine supplementation (1 and 2 mM cysteamine) leads to lower levels of LPO (p<0.01) at 0, 25, and 50 h. Therefore, finding and using the best concentrations of cysteamine in a cooling extender could be effective in saving sheep semen against damages of the cooling storage process

Análisis comparativo del perfil docente del profesorado esperado por los estudiantes de la Universidad de Tarapacá y los de la Universidad de Barcelona.

The revision and evaluation of the teaching practice is a demand of the society that every time demands a better formation of competent professionals in its area. An essential edge in the training process, which must be constant, is the reflection about the task that the educator performs directly and what the skills and abilities that he/she is or should be. The highlight, in this scenario, the opinion that students express about these characteristics, since the power to define or institute them, will allow the development of adaptations to the teaching work that will point precisely to the felt need and will result in better levels of achievement. Therefore, this research was developed with the objective of identifying the teaching competences that the stu dents of the Universidad de Tarapacá (UTA), Chile, expect and then compared the local results with those of the Universidad de Barcelona, Spain. The sampling procedure consisted of placing a survey on the institutional intranet available to all students of the UTA, accepting all the completed surveys. Finally, the sample was constituted by a total of 2584 students, with an average age of 22.4 ±2.51 years, 1145 (44.3%) men and 1439 (55.7%) women. The analysis of the 16 evaluated competences showed that those most expected by the UTA students were: listening to the students, motivating the student in their learning process, using teaching methods that are coherent with the objectives of the subject and using evaluation procedures according to it

Análisis comparativo del perfil docente del profesorado esperado por los estudiantes de la Universidad de Tarapacá y los de la Universidad de Barcelona.

The revision and evaluation of the teaching practice is a demand of the society that every time demands a better formation of competent professionals in its area. An essential edge in the training process, which must be constant, is the reflection about the task that the educator performs directly and what the skills and abilities that he/she is or should be. The highlight, in this scenario, the opinion that students express about these characteristics, since the power to define or institute them, will allow the development of adaptations to the teaching work that will point precisely to the felt need and will result in better levels of achievement. Therefore, this research was developed with the objective of identifying the teaching competences that the stu dents of the Universidad de Tarapacá (UTA), Chile, expect and then compared the local results with those of the Universidad de Barcelona, Spain. The sampling procedure consisted of placing a survey on the institutional intranet available to all students of the UTA, accepting all the completed surveys. Finally, the sample was constituted by a total of 2584 students, with an average age of 22.4 ±2.51 years, 1145 (44.3%) men and 1439 (55.7%) women. The analysis of the 16 evaluated competences showed that those most expected by the UTA students were: listening to the students, motivating the student in their learning process, using teaching methods that are coherent with the objectives of the subject and using evaluation procedures according to it

Foxa1 and Foxa2 in thymic epithelial cells (TEC) regulate medullary TEC and regulatory T-cell maturation

The Foxa1 and Foxa2 transcription factors are essential for mouse development. Here we show that they are expressed in thymic epithelial cells (TEC) where they regulate TEC development and function, with important consequences for T-cell development. TEC are essential for T-cell differentiation, lineage decisions and repertoire selection. Conditional deletion of Foxa1 and Foxa2 from murine TEC led to a smaller thymus with a greater proportion of TEC and a greater ratio of medullary to cortical TEC. Cell-surface MHCI expression was increased on cortical TEC in the conditional Foxa1Foxa2 knockout thymus, and MHCII expression was reduced on both cortical and medullary TEC populations. These changes in TEC differentiation and MHC expression led to a significant reduction in thymocyte numbers, reduced positive selection of CD4+CD8+ cells to the CD4 lineage, and increased CD8 cell differentiation. Conditional deletion of Foxa1 and Foxa2 from TEC also caused an increase in the medullary TEC population, and increased expression of Aire, but lower cell surface MHCII expression on Aire-expressing mTEC, and increased production of regulatory T-cells. Thus, Foxa1 and Foxa2 in TEC promote positive selection of CD4SP T-cells and modulate regulatory T-cell production and activity, of importance to autoimmunity

Mining conflicts around the world: Common grounds from an Environmental Justice perspective

Abstract. This report aims at exploring contemporary mining conflicts in the context of the sustainable development and environmental justice movement. This is done based on 24 real case studies from 18 different countries which are described by local activists and scholars. While 17 of the reported cases focus on conflicts related to metal mining (e.g. gold, silver, copper, zinc, and lead), four address uranium mining and one refers to coal mining. As an example of a new frontier in the industry, a sand mining conflict from India is also reported. All of these cases are directly chosen and reported, either in factsheet or in-depth study format, by EJOs, as part of a knowledge sharing activity well-established in EJOLT between EJOs and the academic community. Although the cases covered here are all quite unique and diverse in terms of type of conflict and geographical setting, they all share a common frame of analysis. First, the project and type of conflict are characterized in a nutshell, with some basic factual background that describe the companies involved, and the communities and locations affected. The roots of the conflicts are explored next, as well as relevant socioeconomic, cultural, health, and ecological impacts and related community claims. Where relevant, means of resistance are also specified with their influence on the project and/or the outcome of the conflict. The report then offers a synthesis of the described mining cases, review their commonalities, link gained insights with research needs and discuss some policy recommendations that might follow from this analysis. Despite its limitations, compiling such a diverse set of mining conflicts that builds on EJO knowledge promotes mutual learning and collaboration among stakeholders, EJOs and academia, which is one of the key objectives of EJOLT