Transcriptomic characterization of the molecular mechanisms induced by RGMa during skeletal muscle nuclei accretion and hypertrophy.

BACKGROUND: The repulsive guidance molecule a (RGMa) is a GPI-anchor axon guidance molecule first found to play important roles during neuronal development. RGMa expression patterns and signaling pathways via Neogenin and/or as BMP coreceptors indicated that this axon guidance molecule could also be working in other processes and diseases, including during myogenesis. Previous works from our research group have consistently shown that RGMa is expressed in skeletal muscle cells and that its overexpression induces both nuclei accretion and hypertrophy in muscle cell lineages. However, the cellular components and molecular mechanisms induced by RGMa during the differentiation of skeletal muscle cells are poorly understood. In this work, the global transcription expression profile of RGMa-treated C2C12 myoblasts during the differentiation stage, obtained by RNA-seq, were reported. RESULTS: RGMa treatment could modulate the expression pattern of 2,195 transcripts in C2C12 skeletal muscle, with 943 upregulated and 1,252 downregulated. Among them, RGMa interfered with the expression of several RNA types, including categories related to the regulation of RNA splicing and degradation. The data also suggested that nuclei accretion induced by RGMa could be due to their capacity to induce the expression of transcripts related to 'adherens junsctions' and 'extracellular-cell adhesion', while RGMa effects on muscle hypertrophy might be due to (i) the activation of the mTOR-Akt independent axis and (ii) the regulation of the expression of transcripts related to atrophy. Finally, RGMa induced the expression of transcripts that encode skeletal muscle structural proteins, especially from sarcolemma and also those associated with striated muscle cell differentiation. CONCLUSIONS: These results provide comprehensive knowledge of skeletal muscle transcript changes and pathways in response to RGMa.

Validation of an Aesthetic Assessment System for Commercial Tasks.

Automatic prediction of the aesthetic value of images has received increasing attention in recent years. This is due, on the one hand, to the potential impact that predicting the aesthetic value has on practical applications. Even so, it remains a difficult task given the subjectivity and complexity of the problem. An image aesthetics assessment system was developed in recent years by our research group. In this work, its potential to be applied in commercial tasks is tested. With this objective, a set of three portals and three real estate agencies in Spain were taken as case studies. Images of their websites were taken to build the experimental dataset and a validation method was developed to test their original order with another proposed one according to their aesthetic value. So, in this new order, the images that have the high aesthetic score by the AI system will occupy the first positions of the portal. Relevant results were obtained, with an average increase of 52.54% in the number of clicks on the ads, in the experiment with Real Estate portals. A statistical analysis prove that there is a significant difference in the number of clicks after selecting the images with the AI system.

Comparison of Outlier-Tolerant Models for Measuring Visual Complexity.

Providing the visual complexity of an image in terms of impact or aesthetic preference can be of great applicability in areas such as psychology or marketing. To this end, certain areas such as Computer Vision have focused on identifying features and computational models that allow for satisfactory results. This paper studies the application of recent ML models using input images evaluated by humans and characterized by features related to visual complexity. According to the experiments carried out, it was confirmed that one of these methods, Correlation by Genetic Search (CGS), based on the search for minimum sets of features that maximize the correlation of the model with respect to the input data, predicted human ratings of image visual complexity better than any other model referenced to date in terms of correlation, RMSE or minimum number of features required by the model. In addition, the variability of these terms were studied eliminating images considered as outliers in previous studies, observing the robustness of the method when selecting the most important variables to make the prediction.

A Genetic Programming-Based Low-Level Instructions Robot for Realtimebattle.

RealTimeBattle is an environment in which robots controlled by programs fight each other. Programs control the simulated robots using low-level messages (e.g., turn radar, accelerate). Unlike other tools like Robocode, each of these robots can be developed using different programming languages. Our purpose is to generate, without human programming or other intervention, a robot that is highly competitive in RealTimeBattle. To that end, we implemented an Evolutionary Computation technique: Genetic Programming. The robot controllers created in the course of the experiments exhibit several different and effective combat strategies such as avoidance, sniping, encircling and shooting. To further improve their performance, we propose a function-set that includes short-term memory mechanisms, which allowed us to evolve a robot that is superior to all of the rivals used for its training. The robot was also tested in a bout with the winner of the previous "RealTimeBattle Championship," which it won. Finally, our robot was tested in a multi-robot battle arena, with five simultaneous opponents, and obtained the best results among the contenders.

Didelphis albiventris: an overview of unprecedented transcriptome sequencing of the white-eared opossum.

BACKGROUND: The white-eared opossum (Didelphis albiventris) is widely distributed throughout Brazil and South America. It has been used as an animal model for studying different scientific questions ranging from the restoration of degraded green areas to medical aspects of Chagas disease, leishmaniasis and resistance against snake venom. As a marsupial, D. albiventris can also contribute to the understanding of the molecular mechanisms that govern the different stages of organogenesis. Opossum joeys are born after only 13 days, and the final stages of organogenesis occur when the neonates are inside the pouch, depending on lactation. As neither the genome of this opossum species nor its transcriptome has been completely sequenced, the use of D. albiventris as an animal model is limited. In this work, we sequenced the D. albiventris transcriptome by RNA-seq to obtain the first catalogue of differentially expressed (DE) genes and gene ontology (GO) annotations during the neonatal stages of marsupial development. RESULTS: The D. albiventris transcriptome was obtained from whole neonates harvested at birth (P0), at 5 days of age (P5) and at 10 days of age (P10). The de novo assembly of these transcripts generated 85,338 transcripts. Approximately 30% of these transcripts could be mapped against the amino acid sequences of M. domestica, the evolutionarily closest relative of D. albiventris to be sequenced thus far. Among the expressed transcripts, 2077 were found to be DE between P0 and P5, 13,780 between P0 and P10, and 1453 between P5 and P10. The enriched GO terms were mainly related to the immune system, blood tissue development and differentiation, vision, hearing, digestion, the CNS and limb development. CONCLUSIONS: The elucidation of opossum transcriptomes provides an out-group for better understanding the distinct characteristics associated with the evolution of mammalian species. This study provides the first transcriptome sequences and catalogue of genes for a marsupial species at different neonatal stages, allowing the study of the mechanisms involved in organogenesis.

Metal Content in Textile and (Nano)Textile Products.

Metals, metallic compounds, and, recently, metallic nanoparticles appear in textiles due to impurities from raw materials, contamination during the manufacturing process, and/or their deliberate addition. However, the presence of lead, cadmium, chromium (VI), arsenic, mercury, and dioctyltin in textile products is regulated in Europe (Regulation 1907/2006). Metal determination in fabrics was performed by inductively coupled plasma-mass spectrometry (ICP-MS) after microwave-assisted acid digestion. The ICP-MS procedure has been successfully validated; relative standard deviations were up to 3% and analytical recoveries were within the 90-107% range. The developed method was applied to several commercial textiles, and special attention has been focused on textiles with nanofinishing (fabrics prepared with metallic nanoparticles for providing certain functionalities). Arsenic content (in textile T4) and lead content (in subsamples T1-1, T1-2, and T3-3) were found to exceed the maximum limits established by the European Regulation 1907/2006. Although impregnation of yarns with mercury compounds is not allowed, mercury was quantified in fabrics T1-2, T5, and T6. Further speciation studies for determining hexavalent chromium species in sample T9 are necessary (hexavalent chromium is the only species of chromium regulated). Some textile products commercialised in Europe included in this study do not comply with European regulation 1907/2006.

Silver nanoparticles assessment in moisturizing creams by ultrasound assisted extraction followed by sp-ICP-MS.

Advances on nanometrology require reliable sample pre-treatment methods for extracting/isolating nanomaterials from complex samples. The current development deals with a discontinuous ultrasonication (60% amplitude, 15 cycles of ultrasound treatment for 59 s plus relaxing stage for 59 s, 20 mL of methanol) method for a fast and quantitative extraction of silver nanoparticles (Ag NPs) from moisturizing creams. Possibilities offered by modern inductively coupled plasma mass spectrometry (ICP-MS) which allow 'single particle' assessment (sp-ICP-MS) have been used for Ag NPs assessment (Ag NPs concentration and Ag size distribution). The relative standard deviation (RSD) of the over-all procedure (Ag NPs concentration in eleven extracts from a same cream) was found to be 5%; whereas, the analytical recovery for spiking experiments with Ag NPs of 20, 40, and 60 nm was found to be within the 90-109% range. The limit of quantification in Ag NPs concentration was established at 8.25 × 105 Ag NPs g-1; whereas, the limit of detection in size was found to be within the 5-13 nm (several equations were used for calculation). Finally, moisturizing creams prescribed for atopic dermatitis and also regular moisturizing creams were analyzed for total Ag, and for Ag NPs characterization (Ag NPs concentration and Ag NPs size distribution) by sp-ICP-MS. Electronic microscopy was also used for comparative (qualitative) purposes.

FGF2, FGF3 and FGF4 expression pattern during molars odontogenesis in Didelphis albiventris.

Odontogenesis is guided by a complex signaling cascade in which several molecules, including FGF2-4, ensure all dental groups development and specificity. Most of the data on odontogenesis derives from rodents, which does not have all dental groups. Didelphis albiventris is an opossum with the closest dentition to humans, and the main odontogenesis stages occur when the newborns are in the pouch. In this study, D. albiventris postnatals were used to characterize the main stages of their molars development; and also to establish FGF2, FGF3 and FGF4 expression pattern. D. albiventris postnatals were processed for histological and indirect immunoperoxidase analysis of the tooth germs. Our results revealed similar dental structures between D. albiventris and mice. However, FGF2, FGF3 and FGF4 expression patterns were observed in a larger number of dental structures, suggesting broader functions for these molecules in this opossum species. The knowledge of the signaling that determinates odontogenesis in an animal model with complete dentition may contribute to the development of therapies for the replacement of lost teeth in humans. This study may also contribute to the implementation of D. albiventris as model for Developmental Biology studies.

Genomic and phenotypic profiles of two Brazilian breast cancer cell lines derived from primary human tumors.

Breast cancer is the most common type of cancer among women worldwide. Research using breast cancer cell lines derived from primary tumors may provide valuable additional knowledge regarding this type of cancer. Therefore, the aim of this study was to investigate the phenotypic profiles of MACL-1 and MGSO-3, the only Brazilian breast cancer cell lines available for comparative studies. We evaluated the presence of hormone receptors, proliferation, differentiation and stem cell markers, using immunohistochemical staining of the primary tumor, cultured cells and xenografts implanted in immunodeficient mice. We also investigated the ability of the cell lines to form colonies and copy number alterations by array comparative genomic hybridization. Histopathological analysis showed that the invasive primary tumor from which the MACL-1 cell line was derived, was a luminal A subtype carcinoma, while the ductal carcinoma in situ (DCIS) that gave rise to the MGSO-3 cell line was a HER2 subtype tumor, both showing different proliferation levels. The cell lines and the tumor xenografts in mice preserved their high proliferative potential, but did not maintain the expression of the other markers assessed. This shift in expression may be due to the selection of an 'establishment' phenotype in vitro. Whole-genome DNA evaluation showed a large amount of copy number alterations (CNAs) in the two cell lines. These findings render MACL-1 and MGSO-3 the first characterized Brazilian breast cancer cell lines to be potentially used for comparative research.

Immunization with rP22 induces protective immunity against Schistosoma mansoni: effects on granuloma down-modulation and cytokine production.

Schistosomiasis remains a significant public health problem in tropical countries and it is recognized as the most important human helminth infection in terms of morbidity and mortality. Although the existing antischistosomal drugs are highly effective, they do not prevent against reinfection or granuloma formation. Therefore, vaccine strategies are essential for the control of schistosomiasis. Our group recently identified the recombinant (r) P22 protein, a component of the adult worm protein fraction PIII that has been shown to engender protective and immunomodulatory effects on murine schistosomiasis. A cDNA clone encoding rP22 was isolated from a Schistosoma mansoni adult worm cDNA library using anti-PIII rabbit serum; it exhibited complete identity with S. mansoni Sm21.7 EF-hand antigen. Confocal microscopy revealed that rP22 is a tegument protein localized on the surface of S. mansoni miracidia and adult worms. Mice immunized with rP22 exhibited a 51% and 22.5% decrease in adult worm burden and in hepatic eggs, respectively. Additionally, rP22 vaccine produced a reduction in 60% of liver granuloma size and 71% of fibrosis in mice, suggesting that rP22 might contribute to down-modulate granulomatous hypersensitivity to S. mansoni eggs. Protective immunity in mice was associated with high titers of rP22-specific IgG antibodies; elevated production of IFN-γ, TNF-α and IL-10; and a reduced level of IL-4. In conclusion, these findings indicate that rP22-based vaccines could be useful to elicit protection and reduce pathology associated to schistosomiasis.