Search Results (34)

Superoxide dismutases (SODs) maintain redox homeostasis through the catalytic dismutation of superoxide anions, thereby affording protection to organisms against oxidative damage. The SOD family, encompassing Cu/Zn-SOD, Mn-SOD, Fe-SOD, and Ni-SOD, exhibits structural diversity and constitutes a multilevel antioxidant defense system with discrete subcellular localizations. Beyond their antioxidant functions, SODs also function as immunomodulatory proteins, regulating the maturation, proliferation, and differentiation of immune cells. They further fulfill a crucial role in host responses to parasitic infections. The current review synthesizes and critically evaluates extant research to comprehensively delineate the molecular architecture of SODs, their intricate post-translational modification (PTM) networks, and their dual regulatory mechanisms at the interface of immunomodulation and pathological processes. This review establishes a critical framework for elucidating the biological significance of redox homeostasis maintenance. Full article

Peptidoglycan (PGN) is a component of bacterial cell walls; its fragments are recognized by the cytoplasmic receptors Nod1 and Nod2, thereby promoting the production of inflammatory cytokines and antibodies. To further elucidate these biological defense mechanisms, a large and stable supply of the PGN fragments via chemical synthesis is essential. However, the synthesis and purification of long PGN fragments are quite challenging due to their low solubility. In this study, we efficiently synthesized PGN fragments via solid-phase oligosaccharide synthesis (SPOS). Using the JandaJel™ Wang resin (JJ-Wang), an octasaccharide glycan chain of PGN was constructed by repeating glycosylation reactions to elongate β-1,4-linked disaccharide units composed of MurNAc and GlcNAc. To enhance reactivity, glycosylation was performed in a mixed solvent comprising C₄F₉OEt/CH₂Cl₂/THF with the intention of promoting substrate concentration onto the solid support through the fluorophobic effect, affording the PGN octasaccharide in a 19% overall yield (10 steps). Subsequently, after deprotection of the O-Fmoc, N-Troc, and ethyl ester groups, N- and O-acetylation proceeded smoothly, owing to the high swelling property of JJ-Wang. Peptide condensation with L-Ala-D-isoGln(OBn) and carboxylic acids was also achieved. Finally, cleavage of the PGN fragment from the resin with TFA afforded the desired octasaccharide with dipeptides in a 2.3% overall yield (15 steps). Full article

The treatment of leishmaniasis has limitations due to drug toxicity and the increasing resistance of the parasite. In this study, we analyze the role of oxidative stress in the pathogenesis and treatment of leishmaniasis, as well as in new therapeutic alternatives of natural origin. The evasion mechanisms against the host immune response involve surface molecules present in the parasite, which modulate oxidative stress to ensure its survival. Drug treatment requires strict monitoring to minimize adverse reactions and ensure patient safety, as mechanisms such as lipid peroxidation, mitochondrial dysfunction, and depletion of antioxidant defenses are associated with drug toxicity. Plant-derived products with antileishmanial activity impact the parasite’s redox balance, inducing apoptosis and reducing its parasitic load. Most studies are still in preliminary stages, making in vivo assays and clinical studies essential, along with the development of accessible formulations. Oxidative stress is involved in the pathogenesis of leishmaniasis, as Leishmania manipulates the host’s redox balance to survive. It also contributes to drug toxicity, as antimonials and amphotericin B increase reactive oxygen species, causing cellular damage. Several plant-derived compounds have demonstrated antileishmanial activity by modulating oxidative stress and promoting parasite apoptosis. Examples include alkaloids from Aspidosperma nitidum, lignans from Virola surinamensis, flavonoids from Geissospermum vellosii, and triterpenoids such as β-sitosterol. Although these compounds show promising selectivity, most studies remain in preliminary stages, requiring in vivo assays and clinical studies to confirm efficacy and safety, as well as the development of affordable formulations. Full article

This study presents extended Immunity Agent-Based Model (IABM) simulations to evaluate vaccination strategies in controlling the spread of infectious diseases. The application of IABM in the analysis of vaccination configurations is innovative, as a vaccinated individual can be infected depending on how their immune system acts against the invading pathogen, without a pre-established infection rate. Analysis at the microscopic level demonstrates the impact of vaccination on individual immune responses and infection outcomes, providing a more realistic representation of how the humoral response caused by vaccination affects the individual’s immune defense. At the macroscopic level, the effects of different population-wide vaccination strategies are explored, including random vaccination, targeted vaccination of specific demographic groups, and spatially focused vaccination. The results indicate that increased vaccination rates are correlated with decreased infection and mortality rates, highlighting the importance of achieving herd immunity. Furthermore, strategies focused on vulnerable populations or densely populated regions prove to be more effective in reducing disease transmission compared to randomly distributed vaccination. The results presented in this work show that vaccination strategies focused on highly crowded regions are more efficient in controlling epidemics and outbreaks. Results suggest that applying vaccination only in the densest region resulted in the suppression of infection in that region, with less intense viral spread in areas with lower population densities. Strategies focused on specific regions, in addition to being more efficient in reducing the number of infected and dead people, reduce costs related to transportation, storage, and distribution of doses compared to the random vaccination strategy. Considering that, despite scientific efforts to consolidate the use of mass vaccination, the accessibility, affordability, and acceptability of vaccines are problems that persist, investing in the study of strategies that mitigate such issues is crucial in the development and application of government policies that make immunization systems more efficient and robust. Full article

Drought stress is a major meteorological threat to crop growth and yield. Barley (Hordeum vulgare L.) is a vital cereal crop with strong drought tolerance worldwide. However, the underlying growth properties and metabolomic regulatory module of drought tolerance remains less known. Here, we investigated the plant height, spike length, effective tiller, biomass, average spikelets, 1000-grain weight, number of seeds per plant, grain weight per plant, ash content, protein content, starch content, cellulose content, and metabolomic regulation mechanisms of drought stress in barley. Our results revealed that the growth properties were different between ZDM5430 and IL-12 under drought stress at different growth stages. We found that a total of 12,235 metabolites were identified in two barley genotype root samples with drought treatment. More than 50% of these metabolites showed significant differences between the ZDM5430 and IL-12 roots. The Kyoto Encyclopedia of Genes and Genomes pathway analysis identified 368 differential metabolites mainly involved in starch and sucrose metabolism, the pentose phosphate pathway, pyrimidine metabolism, phenylalanine, tyrosine, and tryptophan biosynthesis in ZDM5430 under drought stress, whereas the different metabolites of IL-12 under drought stress related to starch and sucrose metabolism, the pentose phosphate pathway, 2-oxocarboxylic acid metabolism, cutin, suberine and wax biosynthesis, carbon metabolism, fatty acid biosynthesis, and C5-branched dibasic acid metabolism. These metabolites have application in the tricarboxylic cycle, the urea cycle, the met salvage pathway, amino acid metabolism, unsaturated fatty acid biosynthesis, phenolic metabolism, and glycolysis. On the other hand, the expression patterns of 13 genes related to the abovementioned bioprocesses in different barley genotypes roots were proposed. These findings afford an overview for the understanding of barley roots’ metabolic changes in the drought defense mechanism by revealing the differently accumulated compounds. Full article

Inflammation, which has important functions in human defense systems and in maintaining the dynamic homeostasis of the body, has become a major risk factor for the progression of many chronic diseases. Although the applied medical products alleviate the general status, they still exert adverse effects in the long term. For this reason, the solution should be sought in more harmless and affordable agents. Microorganisms offer a wide range of active substances with anti-inflammatory properties. They confer important advantages such as their renewable and inexhaustible nature. This review aims to provide the most recent updates on microorganisms of different types and genera, being carriers of anti-inflammatory activity. Full article

The current energy transition combined with the modernization of power systems has provided meaningful transformations in the transmission, distribution, operation, planning, monitoring, and control of power systems. These advancements are heavily dependent on the employment of new computing and communications technologies, which, combined with traditional physical systems, lead to the emergence of cyber–physical systems (CPSs). In this sense, besides the traditional challenges of keeping a reliable, affordable, and safe power grid, one must now deal with the new vulnerabilities to cyberattacks that emerge with the advancement of CPSs. Aware of this perspective and the severity of the ongoing challenges faced by the industry due to cyberattacks, this paper aims to provide a comprehensive survey of the literature on cybersecurity in cyber–physical power systems. For this, clear definitions, historical timelines, and classifications of the main types of cyberattacks, including the concepts, architectures, and basic components that make up, as well as the vulnerabilities in managing, controlling, and protecting, a CPS are presented. Furthermore, this paper presents defense strategies and future trends for cybersecurity. To conduct this study, a careful search was made in relevant academic and industrial databases, leading to a detailed reporting of key works focused on mitigating cyberattacks and ensuring the cybersecurity of modern CPSs. Finally, the paper presents some standards and regulations that technical and international institutions on cybersecurity in smart grids have created. Full article

Represented by reactive security defense mechanisms, cyber defense possesses a static, reactive, and deterministic nature, with overwhelmingly high costs to defend against ever-changing attackers. To change this situation, researchers have proposed moving target defense (MTD), which introduces the concept of an attack surface to define cyber defense in a brand-new manner, aiming to provide a dynamic, continuous, and proactive defense mechanism. With the increasing use of machine learning in networking, researchers have discovered that MTD techniques based on machine learning can provide omni-bearing defense capabilities and reduce defense costs at multiple levels. However, research in this area remains incomplete and fragmented, and significant progress is yet to be made in constructing a defense mechanism that is both robust and available. Therefore, we conducted a comprehensive survey on MTD research, summarizing the background, design mechanisms, and shortcomings of MTD, as well as relevant features of intelligent MTD that are designed to overcome these limitations. We aim to provide researchers seeking the future development of MTD with insight into building an intelligently affordable, optimized, and self-adaptive defense mechanism. Full article

Olea europaea L. folium has been studied for its potential nutraceutical properties. Quantitative and qualitative analyses were conducted on samples of Madural, Verdeal, and Cobrançosa elementary leaves and leave sprouts (mamões) collected in the region of Valpaços, Portugal. Mineral analysis determined the measurements of the levels of several macro- and micro-elements based on ICP-MS techniques. The inorganic analysis in this work allowed us to propose olive leaf extract (OLE) from different cultivars as a viable and affordable source of mineral substrates to address disorders related to essential elements such as Na, K, Mg, Ca, Mn, Fe, and Cu deficiencies. Given the importance of the research on novel therapies, finding a suitable substrate for extracting quality amounts of mineral is a priority. The physiological influence of enzymes dependent on minerals with regard to neuroinflammatory and neurobehavioral, metabolic, cardiovascular, osteodegenerative, anti-aging, pulmonary, and immunological defense disorders might dictate the importance of further research for designing supplementation based on the nutraceutical potential of OLE of these cultivars predominant in the northern region of Portugal. Full article

The use of unmanned aerial vehicles (UAVs) has seen a significant increase over time in several industries such as defense, healthcare, and agriculture to name a few. Their affordability has made it possible for industries to venture and invest in UAVs for both research and commercial purposes. In spite of their recent popularity; there remain a number of difficulties in the design representation of UAVs, including low image analysis, high cost, and time consumption. In addition, it is challenging to represent systems of systems that require multiple UAVs to work in cooperation, sharing resources, and complementing other assets on the ground or in the air. As a means of compensating for these difficulties; in this study; we use a model-based systems engineering (MBSE) approach, in which standardized diagrams are used to model and design different systems and subsystems of UAVs. SysML is widely used to support the design and analysis of many different kinds of systems and ensures consistency between the design of the system and its documentation through the use of an object-oriented model. In addition, SysML supports the modeling of both hardware and software, which will ease the representation of both the system’s architecture and flow of information. The following paper will follow the Magic Grid methodology to model a UAV system across the SysML four pillars and integration of SysML model with external script-based simulation tools, namely, MATLAB and OpenMDAO. These pillars are expressed within standard diagram views to describe the structural, behavior, requirements, and parametric aspect of the UAV. Finally, the paper will demonstrate how to utilize the simulation capability of the SysML model to verify a functional requirement. Full article

Endophytic Bacillus subtilis is a non-pathogenic beneficial bacterium which promotes plant growth and tolerance to abiotic stresses, including drought. However, the underlying physiological mechanisms are not well understood. In this study, the potential role that endogenous salicylic acid (SA) plays in regulating endophytic B. subtilis-mediated drought tolerance in wheat (Triticum aestivum L.) was examined. The study was conducted on genotypes with contrasting levels of intrinsic drought tolerance (drought-tolerant (DT) cv. Ekada70; drought-susceptible (DS) cv. Salavat Yulaev). It was revealed that B. subtilis 10-4 promoted endogenous SA accumulation and increased the relative level of transcripts of the PR-1 gene, a marker of the SA-dependent defense pathway, but two wheat cultivars responded differently, with the highest levels exhibited in DT wheat seedlings. These had a positive correlation with the ability of strain 10-4 to effectively protect DT wheat seedlings against drought injury by decreasing osmotic and oxidative damages (i.e., proline, water holding capacity (WHC), and malondialdehyde (MDA)). However, the use of the SA biosynthesis inhibitor 1-aminobenzotriazole prevented endogenous SA accumulation under normal conditions and the maintenance of its increased level under stress as well as abolished the effects of B. subtilis treatment. Particularly, the suppression of strain 10-4-induced effects on proline and WHC, which are both contributing factors to dehydration tolerance, was found. Moreover, the prevention of strain 10-4-induced wheat tolerance to the adverse impacts of drought, as judged by the degree of membrane lipid peroxidation (MDA) and plant growth (length, biomass), was revealed. Thus, these data provide an argument in favor of a key role of endogenous SA as a hormone intermediate in triggering the defense responses by B. subtilis 10-4, which also afford the foundation for the development of the bacterial-induced tolerance of these two different wheat genotypes under dehydration. Full article

Abiotic stresses, such as drought, salinity, heat, cold, and heavy metals, are associated with global climate change and hamper plant growth and development, affecting crop yields and quality. However, the negative effects of abiotic stresses can be mitigated through exogenous treatments using small biomolecules. For example, the foliar application of melatonin provides the following: it protects the photosynthetic apparatus; it increases the antioxidant defenses, osmoprotectant, and soluble sugar levels; it prevents tissue damage and reduces electrolyte leakage; it improves reactive oxygen species (ROS) scavenging; and it increases biomass, maintains the redox and ion homeostasis, and improves gaseous exchange. Glutathione spray upregulates the glyoxalase system, reduces methylglyoxal (MG) toxicity and oxidative stress, decreases hydrogen peroxide and malondialdehyde accumulation, improves the defense mechanisms, tissue repairs, and nitrogen fixation, and upregulates the phytochelatins. The exogenous application of proline enhances growth and other physiological characteristics, upregulates osmoprotection, protects the integrity of the plasma lemma, reduces lipid peroxidation, increases photosynthetic pigments, phenolic acids, flavonoids, and amino acids, and enhances stress tolerance, carbon fixation, and leaf nitrogen content. The foliar application of glycine betaine improves growth, upregulates osmoprotection and osmoregulation, increases relative water content, net photosynthetic rate, and catalase activity, decreases photorespiration, ion leakage, and lipid peroxidation, protects the oxygen-evolving complex, and prevents chlorosis. Chemical priming has various important advantages over transgenic technology as it is typically more affordable for farmers and safe for plants, people, and animals, while being considered environmentally acceptable. Chemical priming helps to improve the quality and quantity of the yield. This review summarizes and discusses how exogenous melatonin, glutathione, proline, and glycine betaine can help crops combat abiotic stresses. Full article

The Internet of Things (IoT) and the Android operating system have made cutting-edge technology accessible to the general public. These are affordable, easy-to-use, and open-source technology. Android devices connect to different IoT devices such as IoT-enabled cameras, Alexa powered by Amazon, and various other sensors. Due to the escalated growth of Android devices, users are facing cybercrime through their Android devices. This article aims to provide a comprehensive study of the IoT and Android systems. This article classifies different attacks on IoT and Android devices and mitigation strategies proposed by different researchers. The article emphasizes the role of the developer in secure application design. This article attempts to provide a relative analysis of several malware detection methods in the different environments of attacks. This study expands the awareness of certain application-hardening strategies applicable to IoT devices and Android applications and devices. This study will help domain experts and researchers to gain knowledge of IoT systems and Android systems from a security point of view and provide insight into how to design more efficient, robust, and comprehensive solutions. This article discusses different attack vectors and mitigation strategies available to both developers and in the open domain. Certain guidelines are also suggested for application and platform developers, as well as application databases (Google play store), to limit the risk of attack, and users can form their own defense with knowledge regarding keeping hardware and software updated and securing their system with a strong password. Full article

(1) Purpose: To assess the use of the chicken embryo (in ovo) model as an alternative in vivo model for immuno-oncology (IO) drug development, focusing on programmed cell death protein-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) immune checkpoint inhibitors. (2) Methods: First, the presence of immune cells in the model was detected through the immunophenotyping of chicken peripheral blood mononuclear cells (PBMCs) based on fluorescence activated cell sorting (FACS) analysis and the immunohistochemistry (IHC) analysis of in ovo tumor-infiltrating lymphocytes. Second, the cross-reactivity between one anti-human PD-1 Ab, pembrolizumab (KEYTRUDA^®), and chicken PD-1 was verified through the labelling of chicken splenocytes with pembrolizumab by FACS analysis. Third, the blockade effect of pembrolizumab on chicken PBMCs was assessed in vitro through cytotoxicity assay based on MTT. Fourth, the CAM assay was used to estimate the anti-tumor performance of pembrolizumab through the analyses of tumor growth and chicken immune cell infiltration in tumors. Finally, the efficacy of several PD-1 or PD-L1 inhibitors (nivolumab, atezolizumab and avelumab) on tumor growth was further assessed using the CAM assay. (3) Results: The presence of CD3⁺, CD4⁺, CD8⁺ T lymphocytes and monocytes was confirmed by FACS and IHC analyses. During in vitro assays, pembrolizumab cross-reacted with chicken lymphocytes and induced PD-1/PD-L1 blockade, which permitted the restoration of chicken T-cell’s cytotoxicity against human lung cancer H460 tumor cells. All these in vitro results were correlated with in ovo findings based on the CAM assay: pembrolizumab inhibited H460 tumor growth and induced evident chicken immune cell infiltration (with significant chicken CD45, CD3, CD4, CD8 and CD56 markers) in tumors. Furthermore, the potency of the CAM assay was not limited to the application of pembrolizumab. Nivolumab, atezolizumab and avelumab also led to tumor growth inhibition in ovo, on different tumor models. (4) Conclusions: The chicken embryo affords a physiological, immune reactive, in vivo environment for IO research, which allows observation of how the immune system defense against tumor cells, as well as the different immune tolerance mechanisms leading to tumor immune escape. The encouraging results obtained with PD-1/PD-L1 inhibitors in this study reveal the potential use of the chicken embryo model as an alternative, fast, and reliable in vivo model in the different fields of IO drug discovery. Full article

There has been a significant increase in the adoption of unmanned aerial vehicles (UAV) within science, technology, engineering, and mathematics project-based learning. However, the risks that education providers place their student and staff under is often unknown or undocumented. Low-end consumer drones used within the education sector are vulnerable to state-of-the-art cyberattacks. Therefore, datasets are required to conduct further research to establish cyber defenses for UAVs used within the education sector. This paper showcases the development of the ECU-IoFT dataset, documenting three known cyber-attacks targeting Wi-Fi communications and the lack of security in an affordable off-the-shelf drone. At present, there are no publicly available labeled datasets that reflect cyberattacks on the Internet of Flying Things (IoFT). The majority of the publicly available network traffic datasets are emulated and do not reflect the scenarios/attacks from a real test setup. This dataset will be beneficial for both cybersecurity researchers to develop defense strategies and UAV manufacturers to design more secure products. In the future, endeavors will be taken to incorporate newer attacks and create datasets appropriate for big data analysis. Full article