Chronic sustained hypoxia-induced redox remodeling causes contractile dysfunction in mouse sternohyoid muscle

Chronic sustained hypoxia (CH) induces structural and functional adaptations in respiratory muscles of animal models, however the underlying molecular mechanisms are unclear. This study explores the putative role of CH-induced redox remodeling in a translational mouse model, with a focus on the sternohyoid—a representative upper airway dilator muscle involved in the control of pharyngeal airway caliber. We hypothesized that exposure to CH induces redox disturbance in mouse sternohyoid muscle in a time-dependent manner affecting metabolic capacity and contractile performance. C57Bl6/J mice were exposed to normoxia or normobaric CH (FiO2 = 0.1) for 1, 3, or 6 weeks. A second cohort of animals was exposed to CH for 6 weeks with and without antioxidant supplementation (tempol or N-acetyl cysteine in the drinking water). Following CH exposure, we performed 2D redox proteomics with mass spectrometry, metabolic enzyme activity assays, and cell-signaling assays. Additionally, we assessed isotonic contractile and endurance properties ex vivo. Temporal changes in protein oxidation and glycolytic enzyme activities were observed. Redox modulation of sternohyoid muscle proteins key to contraction, metabolism and cellular homeostasis was identified. There was no change in redox-sensitive proteasome activity or HIF-1α content, but CH decreased phospho-JNK content independent of antioxidant supplementation. CH was detrimental to sternohyoid force- and power-generating capacity and this was prevented by chronic antioxidant supplementation. We conclude that CH causes upper airway dilator muscle dysfunction due to redox modulation of proteins key to function and homeostasis. Such changes could serve to further disrupt respiratory homeostasis in diseases characterized by CH such as chronic obstructive pulmonary disease. Antioxidants may have potential use as an adjunctive therapy in hypoxic respiratory disease

Proteomic evaluation of citrate-coated silver nanoparticles toxicity in Daphnia magna

Recent decades have seen a strong increase in the promise and uses of nanotechnology. This is correlated with their growing release in the environment and there is concern that nanomaterials may endanger ecosystems. Silver nanoparticles (AgNPs) have some of the most varied applications, making their release into the environment unavoidable. In order to assess their potential toxicity in aquatic environments, the acute toxicity of citrate-coated AgNPs to Daphnia magna was measured and compared to that of AgNO3. AgNPs were found to be ten times less toxic by mass than silver ions, and most of this toxicity was removed by ultracentrifuging. At the protein level, the two forms of silver had different impacts. Both increased protein thiol content, while only AgNP increased carbonyl levels. In 2DE of samples labelled for carbonyls, no feature was significantly affected by both compounds, indicating different modes of toxicity. Identified proteins showed functional overlap between the two compounds: vitellogenins (vtg) were present in most features identified, indicating their role as a general stress sensor. In addition to vtg, hemoglobin levels were increased by the AgNP exposure while 14-3-3 protein (a regulatory protein) carbonylation levels were reduced by AgNO3. Overall, this study confirms the previously observed lower acute toxicity of AgNPs, while demonstrating that the toxicity of both forms of silver follow somewhat different biologic pathways, potentially leading to different interactions with natural compounds or pollutants in the aquatic environment

Relaxamento como Estratégia na Psicopatologia Bipolar: um estudo de caso

Esta investigação pretendeu pesquisar se o Relaxamento, associado à Terapia Cognitivo Comportamental, contribui para o melhoramento dos sintomas da Perturbação Bipolar em fase Depressiva. É um estudo de caso com uma paciente Bipolar II, em fase Depressiva. Na recolha dos dados foi usado o AAQ II – Questionário de aceitação e Ação, a BDI - Escala de Beck de Autoavaliação da Depressão, o BSI – Inventário de Sintomas Psicopatológicos, a ED – Escala da Derrota, o PANAS – Escala de Afetos Positivos e Negativos, o RRQ – 10 - Questionário de Respostas, a SELFCS - Escala de Auto Compaixão de Neff e a SWLS – Escala de Satisfação com a Vida. Os resultados permitiram concluir que a técnica de relaxamento é útil na regulação emocional. / This research aimed to study if the relaxation, associated to the behavioural cognitive therapy, contributes to the improvement of bipolar perturbation symptoms in a depressive phase. This is a case study of a patient with bipolar type II in a depressive phase. To collect the data it was used the AAQ II (questionnaire of acceptance and action), BDI (Beck’s scale of auto evaluation of depression), BSI (Psychopathologic Symptoms Inventory), ED (defeat scale), PANAS (Positive and Negative affection scale), RRQ-10 (answer’s questionnaire), SELFCS (Neff’s Auto compassion scale) and SWLS (scale of life satisfaction). The results allowed concluding that the relaxation technique is useful in the emotional regulation

Mitochondrial proteomics of the acetic acid – induced programmed cell death response in a highly tolerant Zygosaccharomyces bailii – derived hybrid strain

Very high concentrations of acetic acid at low pH induce programmed cell death (PCD) in both the experimental model Saccharomyces cerevisiae and in Zygosaccharomyces bailii, the latter being considered the most problematic acidic food spoilage yeast due to its remarkable intrinsic resistance to this food preservative. However, while the mechanisms underlying S. cerevisiae PCD induced by acetic acid have been previously examined, the corresponding molecular players remain largely unknown in Z. bailii. Also, the reason why acetic acid concentrations known to be necrotic for S. cerevisiae induce PCD with an apoptotic phenotype in Z. bailii remains to be elucidated. In this study, a 2-DE-based expression mitochondrial proteomic analysis was explored to obtain new insights into the mechanisms involved in PCD in the Z. bailii derived hybrid strain ISA1307. This allowed the quantitative assessment of expression of protein species derived from each of the parental strains, with special emphasis on the processes taking place in the mitochondria known to play a key role in acetic acid – induced PCD. A marked decrease in the content of proteins involved in mitochondrial metabolism, in particular, in respiratory metabolism (Cor1, Rip1, Lpd1, Lat1 and Pdb1), with a concomitant increase in the abundance of proteins involved in fermentation (Pdc1, Ald4, Dld3) was registered. Other differentially expressed identified proteins also suggest the involvement of the oxidative stress response, protein translation, amino acid and nucleotide metabolism, among other processes, in the PCD response. Overall, the results strengthen the emerging concept of the importance of metabolic regulation of yeast PCD.Funding received by iBB-Institute for Bioengineering and Biosciences from FCT-Portuguese Foundation for Science and Technology (UID/BIO/04565/2013) and from Programa Operacional Regional de Lisboa 2020 (Project N. 007317) is acknowledge

Characterization of Coelomic Fluid Cell Types in the Starfish Marthasterias glacialis Using a Flow Cytometry/Imaging Combined Approach

Funding: To the “Maristem COST Action” (CA16203), supported by COST (European Cooperation in Science and Technology), for funding PM STSM visits (February 2019 and November 2020) to the AVC Laboratory.Coelomocytes is the generic name for a collection of cellular morphotypes, present in many coelomate animals, and highly variable among echinoderm classes. The roles attributed to the major types of these free circulating cells present in the coelomic fluid of echinoderms include immune response, phagocytic digestion and clotting. Our main aim in this study was to characterize coelomocytes found in the coelomic fluid of Marthasterias glacialis (class Asteroidea) by using a combination of flow cytometry (FC), imaging flow cytometry (IFC) and fluorescence plus transmission electron microscopy (TEM). Two coelomocyte populations (P1 and P2) identified through flow cytometry were subsequently studied in terms of abundance, morphology, ultrastructure, cell viability and cell cycle profiles. Ultrastructurally, P2 diploid cells were present as two main morphotypes, similar to phagocytes and vertebrate thrombocytes, whereas the smaller P1 cellular population was characterized by low mitotic activity, a relatively undifferentiated cytotype and a high nucleus/cytoplasm ratio. In the present study we could not rule out possible similarities between haploid P1 cells and stem-cell types in other animals. Additionally, we report the presence of two other morphotypes in P2 that could only be detected by fluorescence microscopy, as well as a morphotype revealed via combined microscopy/FC. This integrative experimental workflow combined cells physical separation with different microscopic image capture technologies, enabling us to better tackle the characterization of the heterogeneous composition of coelomocytes populations.publishersversionpublishe

J-PLUS: A wide-field multi-band study of the M15 globular cluster. Evidence of multiple stellar populations in the RGB

The Javalambre Photometric Local Universe Survey (J-PLUS) provides wide field-of-view images in 12 narrow, intermediate and broad-band filters optimized for stellar photometry. Here we have applied J-PLUS data for the first time for the study of Galactic GCs using science verification data obtained for the very metal-poor GC M\,15. Our J-PLUS data provide low-resolution spectral energy distributions covering the near-UV to the near-IR, allowing us to search for MPs based on pseudo-spectral fitting diagnostics. J-PLUS CMDs are found to be particularly useful to search for splits in the sequences formed by the upper red giant branch (RGB) and asymptotic giant branch (AGB) stars. We interpret these split sequences as evidence for the presence of MPs. This demonstrates that the J-PLUS survey will have sufficient spatial coverage and spectral resolution to perform a large statistical study of GCs through multi-band photometry in the coming years.Comment: 11 pages, 11 figures. Accepted for publication @ A&

Drying microalgae using an industrial solar dryer: a biomass quality assessment

Microalgae are considered a promising resource of proteins, lipids, carbohydrates, and other functional biomolecules for food and feed markets. Competitive drying solutions are required to meet future demands for high-quality algal biomass while ensuring proper preservation at reduced costs. Since often used drying methods, such as freeze or spray drying, are energy and time consuming, more sustainable processes remain to be developed. This study tested an indirect and hybrid solar dryer as an alternative to conventional freeze drying of industrially produced Tetraselmis chui and Nannochloropsis oceanica wet paste. The effects of the drying method on biomass quality parameters, including biochemical profiles, functional properties, and microbial safety, were assessed. No significant differences were found between the applied drying technologies for total proteins, carbohydrates, lipids, and fatty acid profiles. On the other hand, some pigments showed significant differences, displaying up to 44.5% higher contents in freeze-dried samples. Minor differences were also registered in the mineral profiles (<10%). Analyses of microbial safety and functional properties of the solar-dried biomass appear adequate for food and feed products. In conclusion, industrial solar drying is a sustainable technology with a high potential to preserve high-quality microalgal biomass for various markets at expected lower costs.info:eu-repo/semantics/publishedVersio

Oak protein profile alterations upon root colonization by an ectomycorrhizal fungus

An increased knowledge on the real impacts of ectomycorrhizal symbiosis in forest 32 species is needed to optimize forest sustainable productivity and thus to improve forests 33 services and their capacity to act as carbon sinks. In this study we investigated the 34 response of an oak species to ectomycorrhizae formation using a proteomics approach 35 complemented by biochemical analysis of carbohydrates levels. Comparative proteome 36 analysis between mycorrhizal and non-mycorrhizal cork oak plants revealed no 37 differences at the foliar level. However, the protein profile of 34 unique oak proteins 38 was altered in the roots. Consistent with the results of the biochemical analysis, the 39 proteome analysis of the mycorrhizal roots suggests a decreasing utilization of sucrose 40 for the metabolic activity of mycorrhizal roots which is consistent with an increased 41 allocation of carbohydrates from the plant to the fungus in order to sustain the 42 symbiosis. In addition, a promotion of protein unfolding mechanisms, attenuation of 43 defense reactions, increased nutrient mobilization from the plant-fungus interface (N 44 and P), as well as cytoskeleton rearrangements and induction of plant cell wall 45 loosening for fungal root accommodation in colonized roots, are also suggested by the 46 results. The suggested improvement in root capacity to take up nutrients accompanied 47 by an increase of root biomass without apparent changes in aboveground biomass 48 strongly re-enforce the potential of mycorrizal inoculation to improve cork oak forest 49 resistance capacity to cope with coming climate change

Caracterização química e avaliação da actividade biológica da framboesa (Rubus Idaeus L.) : Contribuição para o desenvolvimento de uma alegação de saúde

info:eu-repo/semantics/publishedVersio