Developing biomimetic cartilaginous tissues that support locomotion while maintaining chondrogenic behavior is a major challenge in the tissue engineering field. Specifically, while locomotive forces ...demand tissues with strong mechanical properties, chondrogenesis requires a soft microenvironment. To address this challenge, 3D cartilage‐like tissue is fabricated using two biomaterials with different mechanical properties: a hard biomaterial to reflect the macromechanical properties of native cartilage, and a soft biomaterial to create a chondrogenic microenvironment. To this end, a bath composed of an interpenetrating polymer network (IPN) of polyethylene glycol (PEG) and alginate hydrogel (MPa order compressive modulus) is developed as an extracellular matrix (ECM) with self‐healing properties. Within this bath supplemented with thrombin, human mesenchymal stem cell (hMSC) spheroids embedded in fibrinogen are 3D bioprinted, creating a soft microenvironment composed of fibrin (kPa order compressive modulus) that simulate cartilage's pericellular matrix and allow a fast diffusion of nutrients. The bioprinted hMSC spheroids present high viability and chondrogenic‐like behavior without adversely affecting the macromechanical properties of the tissue. Therefore, the ability to locally bioprint a soft and cell stimulating biomaterial inside of a mechanically robust hydrogel is demonstrated, thereby uncoupling the micro‐ and macromechanical properties of the 3D printed tissues such as cartilage.
In this work, 3D bioprinting technology is used to develop a biomimetic cartilage‐like tissue with near‐paradoxical mechanical properties, being soft at the cellular level, due to the soft bioink composed of human bone marrow mesenchymal stem cells in the form of spheroids embedded in fibrinogen, and the stiff polyethylene glycol and alginate bath, showing great potential for cartilage regeneration studies.
The residential environment is constantly evolving technologically. With this evolution, sensors have become intelligent interconnecting home appliances, personal computers, and mobile devices. ...Despite the benefits of this interaction, these devices are also prone to security threats and vulnerabilities. Ensuring the security of smart homes is challenging due to the heterogeneity of applications and protocols involved in this environment. This work proposes the FamilyGuard architecture to add a new layer of security and simplify management of the home environment by detecting network traffic anomalies. Experiments are carried out to validate the main components of the architecture. An anomaly detection module is also developed by using machine learning through one-class classifiers based on the network flow. The results show that the proposed solution can offer smart home users additional and personalized security features using low-cost devices.
The successful implementation of the Convention on Biological Diversity's post‐2020 Global Biodiversity Framework will rely on effective translation of targets from global to national level and ...increased engagement across diverse sectors of society. Species conservation targets require policy support measures that can be applied to a diversity of taxonomic groups, that link action targets to outcome goals, and that can be applied to both global and national data sets to account for national context, which the species threat abatement and restoration (STAR) metric does. To test the flexibility of STAR, we applied the metric to vascular plants listed on national red lists of Brazil, Norway, and South Africa. The STAR metric uses data on species’ extinction risk, distributions, and threats, which we obtained from national red lists to quantify the contribution that threat abatement and habitat restoration activities could make to reducing species’ extinction risk. Across all 3 countries, the greatest opportunity for reducing plant species’ extinction risk was from abating threats from agricultural activities, which could reduce species’ extinction risk by 54% in Norway, 36% in South Africa, and 29% in Brazil. Species extinction risk could be reduced by a further 21% in South Africa by abating threats from invasive species and by 21% in Brazil by abating threats from urban expansion. Even with different approaches to red‐listing among countries, the STAR metric yielded informative results that identified where the greatest conservation gains could be made for species through threat‐abatement and restoration activities. Quantifiably linking local taxonomic coverage and data collection to global processes with STAR would allow national target setting to align with global targets and enable state and nonstate actors to measure and report on their potential contributions to species conservation.
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•Cellulose nanowhiskers were used to enhance the adsorption capacity of chitosan hydrogel.•The resulting composite showed improved adsorption capacity towards methylene blue (MB).•The ...highest MB adsorption (1968mg/g) was observed for the composite at 5w/w-% nanowhiskers.•Desorption experiments showed that 75% of loaded-MB could be recovered at pH 1 solution.•The post-utilized composite can be recycled and reused (5 times) with 2% of efficiency loss.
Cellulose nanowhiskers (CNWs, 90% crystalline) were used to enhance the adsorption capacity of chitosan-g-poly(acrylic acid) hydrogel. The composites up to 20w/w-% CNWs showed improved adsorption capacity towards methylene blue (MB) as compared to the pristine hydrogel. At 5w/w-% CNWs the composite presented the highest adsorption capacity (1968mg/g). The maximum removal of MB (>98% of initial concentration 2000mg/L) was achieved quickly (60min) at room temperature, pH 6, and at low ionic strength (0.1M). Adsorption mechanism was explained with the Langmuir type I model suggesting the formation of a MB monolayer on the adsorbent surface. The interaction between the adsorbent and MB molecules was explained by chemisorption, as suggested by the pseudo-second-order kinetic model. Desorption experiments showed that 75% of loaded-MB could be recovered from the adsorbent by its immersion in a pH 1 solution. Additional experiments showed the post-utilized composite could be regenerated and reused for at least 5 consecutive adsorption/desorption cycles with minimum efficiency loss (∼2%).
Despite the large number of reports of species of Clinostomum from vertebrate hosts in South America, studies evaluating the molluscan transmitters of these parasites are scarce. In the present ...study, clinostomatoid cercariae shed from 0.02% (4/17,485) specimens of Biomphalaria spp., collected at the Pampulha reservoir, Belo Horizonte, Minas Gerais, Brazil, were used for experimental infection of Poecilia reticulata. Samples of cercariae from molluscs and metacercariae experimentally obtained from fish were subjected to morphological and molecular analyses and compared with species of Clinostomum reported in the Americas. The cercariae and metacercariae, here identified as Clinostomum sp., present general morphology similar to that reported for Clinostomum marginatum, however, from molecular point of view, differ significantly from North American C. marginatum and other species of Clinostomum reported in South America. These results suggest that the diversity of Clinostomum found in Brazil may be underestimated. Additional studies aimed at molecular characterization of South American species of Clinostomum, including the finding of specimens with sequences similar to that reported for C. marginatum in North America are required.
Coastal environments, such as those in the Santa Catarina State (SC, Brazil), are considered the primary receptors of anthropogenic pollutants. In this study, our objective was to evaluate the levels ...of emerging contaminants (ECs) and persistent organic pollutants (POPs) in indigenous Crassostrea gasar oysters from different regions of SC coast in the summer season (March 2022). Field collections were conducted in the São Francisco do Sul, Itajaí, Florianópolis and Laguna coastal zones. We analyzed the bioaccumulation levels of 75 compounds, including antibiotics (AB), endocrine disruptors (ED), non-steroidal anti-inflammatory drugs (NSAIDs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and pesticides. Furthermore, we assessed biomarker responses related to biotransformation, antioxidant defense, heat shock protection and oxidative damage in oysters' gills. Prevalence of ECs was observed in the central and southern regions, while the highest concentrations of POPs were detected in the central-northern regions of SC. Oysters exhibited an induction in biotransformation systems (cyp2au1 and cyp356a1, sult and GST activity) and antioxidant enzymes activities (SOD, CAT and GPx). Higher susceptibility to lipid peroxidation was observed in the animals from Florianópolis compared to other regions. Correlation analyses indicated possible associations between contaminants and environmental variables in the biomarker responses, serving as a warning related to climate change. Our results highlight the influence of anthropogenic activities on SC, serving as baseline of ECs and POPs levels in the coastal areas of Santa Catarina, indicating more critical zones for extensive monitoring, aiming to conserve coastal regions.
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•75 compounds were detected in oysters C. gasar from SC.•CYP450 and SULT genes up-regulated associated to anthropogenic contaminants in different sites.•Enhanced SOD, CAT and GPx activities indicate pro-oxidant conditions in the central-northern areas.•Oysters from Florianópolis showed greater susceptibility to oxidative damage in the gills.•Differences in biomarkers responses may be associated to chemical and environmental stressors.
Schistosomiasis is one of the most significant neglected tropical diseases, affecting around 260 million people worldwide, and Praziquantel is currently the only available drug for the treatment of ...infected persons. Thus, the search for new schistosomicidal compounds is urgent. The objective of this study was to investigate of the schistosomicidal effect of barbatic acid, a lichen metabolite, on adult worms of Schistosoma mansoni. The in vitro schistosomicidal effect was evaluated through the assessment of motility and mortality, cellular viability of the worms and ultrastructural analysis through scanning electron microscopy. To evaluate the cytotoxicity of barbatic acid, a cell viability assay was performed with human peripheral blood mononuclear cells. Barbatic acid showed a schistosomicidal effect after 3 h of exposure. At the end of 24 h the concentrations of 50–200 μM presented lethality on the worms. Motility changes were observed at sublethal concentrations. The IC50 obtained by the cell viability assay for S. mansoni was 99.43 μM. Extensive damage to the worm's tegument was observed from 25 μM. No cytotoxicity was observed on human peripheral blood mononuclear cells. This report provides data showing the schistosomicidal effect of barbatic acid on S. mansoni, causing death, motility changes and ultrastructural damage to worms. In addition, barbatic acid was shown to be non-toxic to human peripheral blood mononuclear cells at concentrations that are effective against S. mansoni.
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•Barbatic acid exhibited schistosomicidal effect against adult S. mansoni.•Motility changes were observed in S.mansoni at all concentrations after 24 h.•Tegumentary damages were caused by the barbatic acid in Schistosoma mansoni.•No cytotoxicity was observed on PBMC exposed to barbatic acid after 72 h.
Increasing local people and indigenous communities' participation on restoration programs is widely recommended as a way to increase restoration long‐term benefits and local people's commitment with ...restored lands. Here, we demonstrate how traditional knowledge can provide crucial information on usefulness of plant species that increases direct value of forest and landscape restoration programs. Our study analyzed secondary data from 73 studies that assessed indigenous and local knowledge regarding plant's utility across the densely populated dry forest of the Brazilian Caatinga. Our results suggest that highly valued plants represent a relatively small number of useful species (52 out of 632 useful species) that account for more than half of the plant services (i.e. functional space represented by the uses people give to plants). Interestingly, these plants belonged to closely related lineages, suggesting that people must select plants based on phylogenetically conserved traits that provide utility. We propose that accounting for indigenous and local knowledge in early phases of restoration process such as species selection can both maximize classical restoration targets (e.g. species diversity) and increase delivery of ecosystem services to forest‐dependent people. Such an interdisciplinary integration moves us a step closer to ambitious targets set for global ecosystem restoration based on fair and inclusive participation of indigenous people and local communities.
Pharmaceuticals, such as anti-inflammatory nonsteroidal drugs, are frequently detected in aquatic ecosystems. Studies about the effects of these substances in nontarget organisms, such as bivalves, ...are relevant. The aim of this study was to evaluate the effects on antioxidant status caused by ibuprofen (IBU) in oysters Crassostrea gigas exposed for 1, 4, and 7 days at concentrations 1 and 100 μg L⁻¹. Levels of IBU in tissues of oysters, as well as cell viability of hemocytes, were measured. The transcription of cytochrome P450 genes (CYP2AU2, CYP356A1, CYP3071A1, CYP30C1), glutathione S-transferase isoforms (GST-ω-like and GST-π-like), cyclooxygenase-like (COX-like), fatty acid binding protein-like (FABP-like), caspase-like, heat shock protein-like (HSP70-like), catalase-like (CAT-like), and the activity of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione S-transferase (GST) were also evaluated in the gills of oysters. The highest levels of IBU were observed in animals exposed to 100 μg L⁻¹. A significant upregulation of CYP2AU1, CYP356A1, CYP3071A1, GST-ω-like, GST-π-like, COX-like, and FABP-like was observed in oysters exposed to IBU under different experimental conditions. Oysters exposed to 1 μg L⁻¹ for 7 days showed a significantly higher transcription of CYP2AU2, CYP356A1, CYP3071A1, GST-ω-like, and GST-π-like but lower GR activity. In conclusion, C. gigas exposed to environmentally relevant concentrations of IBU (1 μg L⁻¹) exhibited increased transcription of certain genes and alterations on antioxidant and auxiliary enzymes, which could, in the the long term, cause damages to exposed organisms.
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