Brazilian Journal of Science
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Effect of amino acid-enriched nutrient solutions on early growth of tomato and scarlet eggplant
No full textExtensive vegetable cultivation requires large areas and labor, increasing production costs. An alternative is hydroponic production, where the plant receives all the nutrients in the necessary concentrations to complete its entire cycle. This study aims to evaluate the initial development of tomato and scarlet eggplant grown in a nutrient solution containing different amino acids. Two simultaneous experiments were conducted in April 2024 at the Andradina Educational Foundation, located in the municipality of Andradina, São Paulo state. The experimental design was completely randomized (CRD). Tomato plants (Solanum lycopersicum L.) and scarlet eggplant (Solanum aethiopicum gr. Scarlet eggplant) were grown in a nutrient solution containing amino acids: (Control) no amino acids, Tryptophan, Lysine, Cysteine, Phenylalanine and all amino acids, comprising six treatments, with four replicates totaling 24 plots. Each plot consisted of one seedling, and the concentration of each amino acid was 10 mg L-1 of nutrient solution. Tomatoes responded better to the presence of amino acids in the nutrient solution. The combination of the amino acids tryptophan, lysine, cysteine, and phenylalanine resulted in enhanced tomato and scarlet eggplant development when grown in nutrient solution. The use of amino acids in nutrient solution may be an alternative to improving the initial development parameters of tomatoes and scarlet eggplant. Lysine and phenylalanine supplementation improved tomato early growth and nitrogen assimilation, while scarlet eggplant responses were moderate. Further studies should evaluate long-term yield and economic feasibility
Analysis of the coupling of twenty-five benzothiazole analogs with the β1-adrenergic receptor using a theoretical model
No full textSome benzothiazoles have been developed with biological activity on the cardiovascular system through interaction with different biomolecules; however, the coupling with the β1-adrenergic receptor is not clear. This research aimed to determine the interaction of some benzothiazole analogs (1-25) with the β1-adrenergic receptor using some theoretical models. In this way, 2ycv protein and the controls (metoprolol, propranolol, and cyanopindolol) were used as theoretical tools in the DockingServer software. The results showed differences in the interaction of benzothiazole derivatives compared with the controls. Other data indicate that the inhibition constant (Ki) for benzothiazole analogs 10, 22, 23, and 25 was lower compared with metoprolol and cyanopindolol. All these data indicate that compounds 10, 22, 23, and 25 may act as β1-adrenergic receptor inhibitors, translated into changes in blood pressure. Therefore, the benzothiazole derivatives 10, 22, 23, and 25 could be good antihypertensive agents
The plasma ball in physics teaching: A classroom approach to plasma ionization
No full textPlasma is recognized by Physics as the fourth state of matter. However, the study of plasmas in schools and universities often faces challenges, mainly due to the high cost of science and physics laboratories, which can be inaccessible to many groups of students. As a viable and affordable alternative, devices such as the plasma ball have been used in teaching this physical state of matter, even allowing the quantification of electric fields and the observation of electromagnetic waves. This study aimed to use a low-cost plasma ball in teaching a university-level Physics class, enabling hands-on experiments related to the determination of electric and magnetic fields. For this purpose, a low-cost digital sensor for electromagnetism and electric fields, a neon lamp, and a metallic coin were used. Students learned how to calculate the power of the plasma ball and explore the concepts of electric fields and electromagnetism, when present. The introduction of simple and engaging teaching tools significantly contributed to the students' involvement. They showed increased interest and ease in understanding the concepts related to the Physics of Electromagnetic Interactions (Electromagnetism), highlighting the pedagogical potential of accessible instruments in the teaching-learning process. Therefore, Physics classes must include basic, low-cost equipment or materials that can be easily constructed from readily available resources to enhance the teaching of this exact science
Entropic lifespan: Disorder and transformation in human life from birth to death
No full textThis study constructs an interdisciplinary framework to investigate entropy’s role across human life (biological, psychological, social) and natural systems, grounded in the thermodynamic principle of increasing disorder. The background reveals entropy’s relevance in aging, cognition, social roles, and ecosystems, yet a cohesive model remains undeveloped. The purpose is to integrate these domains, analyzing entropy from birth/emergence to death/collapse. Methods employ a mixed-model simulation with a modified Shannon entropy approach, tracking entropy in cellular degradation, cognitive disorder/growth, role dissolution/reorganization, and ecosystem decay over 100 years, with data evaluated at key stages (0, 20, 40, 70, 100 years). Findings indicate a synchronized entropy increase: biological from 0.10 to 4.00, psychological from 0.10 to 3.50, social from 0.10 to 3.00, and natural from 0.10 to 3.50, with midlife dips in psychological and social entropy due to adaptive processes. Strong correlations (e.g., biological vs. natural, r = 0.96) affirm a universal entropic pattern. The conclusion establishes entropy as a unifying framework, linking human aging to natural decay, with broad implications for health and ecology. Recommendations include empirical validation with longitudinal data, machine learning for dynamic modeling, and interventions (e.g., cognitive training, reforestation) to counter entropy’s effects. This framework bridges disciplines, providing a novel perspective on life’s entropic trajectory
Effect of whole plant extract of Evolvulus alsinoides on thermal stress resistance and longevity in Caenorhabditis elegans
No full textThe popular Ayurvedic plant Evolvulus alsinoides is known to have adaptogenic properties. Adaptogens reduce stress and anxiety and thereby promote the overall well-being of the individual. Since chronic stress is associated with lower than normal lifespan expectance, any herbs known to reduce the stress should have the reverse impact. Therefore, this research aimed to study the anti-ageing activity of Evolvulus alsinoides in the well-established aging model Caenorhabditis elegans. The longevity-enhancing impact was assessed under the optimum growth and survival conditions for the C. elegans. Oxidative stress was induced by the use of Paraquat in N2 wild-type C. elegans, and the thermal stress was induced in transgenic C. elegans TJ 356, which expressed Green fluorescence Protein (GFP) under the control of heat shock protein promoters for the visualization of induction of anti-stress genes. The impact of the stress was analyzed by the lifespan analysis, and data were analyzed by the Kaplein Meyer statistical analysis. The results indicated that E. alsinoides extracts dose-dependently increased the mean lifespan of C. elegans by 18.0% and 26.2% at the concentrations of 0.1 mg/mL-1 and 1 mg/mL-1 under optimum growth and survival conditions, respectively. The survival rates of E. alsinoides extract-fed C. elegans have been greater than those of untreated C. elegans against thermal-induced stress. For Oxidative stress, the E. alsinoides treatment was non-significant. It was found that Evolvulus alsinoides extract promotes longevity in Caenorhabditis elegans by promoting stress tolerance and by tinkering with the insulin/IGF signaling pathway
Challenges and strategies in the fight against antimicrobial resistance
No full textThis study aims to evaluate the scientific literature on the challenges and strategies adopted in the fight against antimicrobial resistance. This study is a literature review, carried out in the SciELO, BVS, and PubMed databases, to analyze the challenges faced and the strategies employed in the fight against antimicrobial resistance. The challenges identified in the fight against antimicrobial resistance include the inappropriate use of antibiotics, the lack of regulation, the limited access to adequate treatments in certain areas, and the rapid adaptation of pathogens. Regarding the strategies, adopting measures for the rational use of antimicrobials, public awareness policies, and medical training, investments in research for the development of new antimicrobials, improvements in epidemiological surveillance, and the implementation of strict regulations on the use of antibiotics stand out. These results aim to provide a basis for more effective public policies in the fight against antimicrobial resistance. With the growing impact of antimicrobial resistance on both public health and the global economy, it is necessary and/or essential to implement effective strategies to contain its spread. Furthermore, the implementation of public policies, such as the WHO global plan and the Brazilian national plan, plays a fundamental role in mitigating the problem. Cooperation between the health sectors, pharmaceutical industries, and society is essential, since it can prevent the worsening of this crisis, ensuring the effectiveness of future available treatments
Silver nanoparticles as an antibacterial agent: a literature review
No full textGrowing bacterial resistance to antibiotics represents a serious threat to global health. In this context, silver nanoparticles (AgNPs) have emerged as promising alternatives due to their potent antimicrobial effect and ability to inhibit biofilm formation. This study aims to evaluate the potential of AgNPs as antibacterial agents through a theoretical analysis. A qualitative systematic review was conducted on silver nanoparticles, focusing on their antimicrobial properties, using inclusion and exclusion criteria to select 27 relevant articles from the BVS and PubMed databases. The antibacterial activity of AgNPs is influenced by factors such as size, shape and stability, and they are effective at disrupting bacterial membranes and biofilms via the release of silver ions and the generation of reactive oxygen species (ROS), as well as depending on controlled conditions to optimize their efficiency and avoid aggregation. The findings indicate that AgNPs represent a promising alternative in the fight against bacterial infections, contributing significantly to the advancement of research in this area
Integrative machine learning reveals potential signature genes using transcriptomics in colon cancer
No full textColon cancer is a significant health burden in the world and the second leading cause of cancer-related deaths. Despite advancements in diagnosis and treatment, identifying potential biomarkers for early detection and therapeutic targets remains challenging. This study used an integrative approach combining transcriptomics and machine learning to identify signature genes and pathways associated with colon cancer. RNA-Seq data from The Cancer Genome Atlas- Colon Adenocarcinoma (TCGA-COAD) project, comprising 485 samples, were analyzed in this study. Differential gene expression analysis revealed 657 upregulated and 8,566 downregulated genes. Notably, EPB41L3, TSPAN7, and ABI3BP were identified as highly upregulated, while LYVE1, PLPP1, and NFE2L3 were significantly downregulated in tumor samples. Gene Set Enrichment Analysis (GSEA) identified dysregulated pathways, including E2F targets, MYC targets, and G2M checkpoints, underscoring cell cycle regulation and metabolic reprogramming alterations in colon cancer. Machine learning models-Random Forest, Neural Networks, and Logistic Regression-achieved high classification accuracy (97–99%). Key genes consistently identified across these models highlight their potential translational relevance as biomarkers. This study integrates differential expression analysis, pathway enrichment, and machine learning to uncover critical insights into colon cancer biology. The study lays the groundwork for developing diagnostic and therapeutic strategies, with the identified genes and pathways serving as potential candidates for further validation and clinical applications. This approach exemplifies the potential of precision medicine to advance colon cancer research and improve patient outcomes
Solidago species in grasslands of Paraguay and their relationship to hepatic photosensitivity in cattle
No full textParaguayan livestock production uses forage grasses as a basic diet. Many species of weeds grow in these pastures, and some of them, like the Solidago genus, are toxic to the animals. This genus is reported to cause hepatic photosensitivity in cattle due to the toxic compound, saponins, contained mainly in the leaves. Saponins induce liver damage because they hamper the breakdown of photodynamic metabolites like phylloerythrin, formed from chlorophyll metabolism. Some species of Solidago are recognized in South America, but only two species are reported in Paraguay, and have been a cause of confusion in their identification and distribution due to the great morphological similarity they have. In the past, Solidago chilensis was the only species recorded in Paraguay and was related to causing hepatic photosensitivity in cattle. However, recent studies of the genus have demonstrated that Solidago microglossa is the dominant species of the genus Solidago in Paraguay, widely distributed across these grasslands. Therefore, the objective of this research is to define the dominant species of Solidago in Paraguay and as the primary cause behind photosensitive health disorders in cattle
Influence of NiSO4 doses on agronomic and bioaccumulative parameters in maize (Zea mays) plants during the vegetative stage
No full textAccording to the list of essential micronutrients for agriculturally important plants, nickel (Ni) plays a key role in various physiological processes. This study aimed to evaluate the agronomic and bioaccumulative parameters of Ni in shoot and root tissues of transgenic maize plants during the vegetative phase under different Ni concentrations. Concentrations ranging from 0 to 600 mg L-1 of Ni, using NiSO4·5H2O as the source, were prepared and applied directly into the planting furrow at sowing of the transgenic maize hybrid Pioneer P3601 PWU. Standard cultural practices were carried out throughout the experimental period. Maize plants at the V7 stage were collected and analyzed for root and shoot length, fresh and dry biomass of roots and shoots, and Ni bioaccumulation in both tissues. The data showed that Ni doses affected shoot fresh mass, with a maximum of 0.82 g at 600 mg L-1, and bioaccumulative content in shoots and especially in roots, reaching 1.92 and 29.31 mg kg-1, respectively, at the same concentration. Ni doses influenced only shoot dry mass among the agronomic parameters, and the greatest bioaccumulative effect was observed in the roots of the transgenic maize hybrid Pioneer P3601 PWU