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Abstract Despite the international effort to improve laboratory animal welfare through the 3R principles (Reduce, Refine, Replace), many scientists still fail to implement and report their assessment of pain and well-being, likely due to concerns regarding the potential effects of analgesics on experimental outcomes. This study aimed to determine whether refining our viral encephalitis model with perioperative analgesia could enhance well-being and recovery after intracerebral virus infection without impacting disease outcomes. We routinely use the Theiler’s Murine Encephalomyelitis Virus (TMEV) model to study virus-induced epilepsy. Given the crucial role of immune cell activation in acute seizure development, we evaluated the effects of the non-steroidal anti-inflammatory drug (NSAID) meloxicam on inflammation, neurodegeneration, and neuronal cell proliferation at 7 days post-infection (dpi). Overall, the impact of virus infection on well-being was less severe than anticipated, and meloxicam treatment did not affect well-being or nest building behavior in TMEV-infected mice. Furthermore, meloxicam treatment did not influence key experimental readouts such as seizure burden, central inflammatory response, neurodegeneration, or neuronal proliferation within the hippocampus. Notably, animals experiencing seizures displayed heightened inflammatory responses and neurodegeneration, which were not influenced by meloxicam treatment. In summary, perioperative analgesia did not compromise key outcome measures such as seizure frequency, inflammation, and neurodegeneration or -regeneration in the TMEV model. However, it also did not add any significant benefits to well-being in the first week after intracranial injections.

Abstract Properties of pH‐responsive electrospun nanofibers incorporated with biocompatible/degradable Carbopol, commonly used in pharmaceuticals and personal care products, are reported. Sonication of Carbopol dispersions prior to electrospinning leads to uniform incorporation into fibers of the host polymer polyvinylpyrrolidone. The hydration behavior is strongly influenced by pH conditions, forming a viscous network at higher pH. Since Carbopol is more responsive to higher pH, at pH > 6 increasing Carbopol concentration leads to increased uptake volume of buffer solution, faster uptake rate and complete gel formation. The physical spreadability (resulting from a combination of viscoelastic properties and the structural polymer network) of the hydrated fibers is evaluated for multiple Carbopol concentrations and pH conditions. At low starting pH of 4, increasing the Carbopol amount results in slightly increasing viscosity while maintain solution pH. On the other hand, at high starting pH of 8 increasing Carbopol concentrations result in significant reduction in the pH of the buffer solution, which in turn decreases the viscosity of the gel and increases its spreadability. These findings provide guidelines for rational designs of pH responsive Carbopol fibers for various applications, including drug delivery, wound dressing, contraceptive devices, and prevention of sexually transmitted diseases.

Infections impacting the central nervous system (CNS) constitute a substantial predisposing factor for the emergence of epileptic seizures. Given that epilepsy conventionally correlates with hippocampal sclerosis and neuronal degeneration, a potentially innovative avenue for therapeutic intervention involves fostering adult neurogenesis, a process primarily occurring within the subgranular zone of the dentate gyrus (DG) through the differentiation of neural stem cells (NSC). While experimental seizures induced by chemoconvulsants or electrical stimulation transiently enhance neurogenesis, the effects of encephalitis and the resultant virus-induced seizures remain inadequately understood. Thus, this study employed the Theiler's Murine Encephalomyelitis Virus (TMEV) model of virus-induced seizures in adult C57BL/6J mice to investigate the impact of infection-induced seizures on neurogenesis at three distinct time points [3, 7, and 14 days post-infection (dpi)]. Immunohistochemical analysis revealed a reduction in the overall number of proliferating cells post-infection. More notably, the specific cell types exhibiting proliferation diverged between TMEV and control (CTR) mice: (1) Neuronal progenitors (doublecortin, DCX+) were almost entirely absent at 3 dpi in the dorsal DG. They resumed proliferation at 14 dpi, but, did not recover to CTR levels, and displayed aberrant migration patterns. (2) The number of proliferating NSCs significantly decreased within the dorsal DG of TMEV mice at 14 dpi compared to CTR, while (3) a heightened population of proliferating astrocytes was observed. Most observed changes were not different between seizing and non-seizing infected mice. In summary, our findings demonstrate that viral infection rapidly depletes neuronal progenitor cells and causes aberrant migration of the remaining ones, potentially contributing to hyperexcitability. Additionally, the increased differentiation toward glial cell fates in infected mice emerges as a possible additional pro-epileptogenic mechanism.

Utilizar filmes comerciais em sala de aula é uma estratégia didática para abordar e refletir sobre diferentes temáticas correlatas à Ciência. O presente estudo qualitativo em educação teve como objetivo analisar o potencial do filme Sonhos Tropicais como desencadeador de discussões sobre Educação em Saúde (ES) e negacionismo científico com professores de Ciências Biológicas em formação inicial. Metodologicamente, a pesquisa foi fundamentada na análise microgenética e os sujeitos foram licenciandos/as em Ciências Biológicas de uma Instituição de Ensino Superior (IES). Os dados empíricos emergiram da análise das discussões pós-filme e dos Diários de Formação dos licenciandos/as. As discussões dos resultados estão ancoradas na abordagem Histórico-Cultural proposta por Vigotski. Este estudo utiliza a metáfora dos ventos para evidenciar o papel didático do filme em sala de aula, dos significados e pontos de reflexões no debate das temáticas ES e negacionismo da Ciência e da Alfabetização Científica. Concluímos que, ao utilizar filmes no ensino, a ação intencional do professor intermediador é essencial, uma vez que ele assume papel central na condução de discussões e no desenvolvimento de posicionamentos críticos dos/as licenciandos/as para o contexto social em que estão inseridos, além de contribuir com a construção do conhecimento científico dos sujeitos.

Abstract Gray rot and grape ripe rot stand out as important vineyard diseases, being caused by the phytopathogens Botrytis cinerea and Colletotrichum acutatum, respectively. Control is usually conducted with synthetic fungicides that can cause problems for human health and the environment. Thus, searching for new alternative disease management methods is necessary, including using essential oil (EO) with fungicidal activity. The present study aimed to evaluate the chemical composition and fungicidal effect of Rosmarinus officinalis EO, as well as its fractions on the mycelial growth and conidial germination of B. cinerea and C. acutatum, in vitro and in vivo. The EO had α-pinene and 1,8-cineole as major compounds. In the vacuum fractional distillation, there was a variation in the chemical composition and the relative quantity of each compound according to the fraction analyzed (fractions of the bottom and top of the column). The in vitro results showed that the EO and its fractions had a fungicidal action on B. cinerea and C. acutatum. In post-harvest tests with 'Isabella' grapes, rosemary EO and its fractions reduced the incidence and severity of gray rot and grape ripe rot in preventive and curative treatments. In the field trial conducted in an 'Isabella' grape vineyard, the concentrations of the bottom fraction of rosemary EO reduced the incidence and severity of the grape ripe rot. They did not change the qualitative parameters of the evaluated grapes, showing that the bottom fraction of rosemary EO can be applied in the vineyard as a biofungicide to control this disease.

Purpose: The use of biochar and its products has been increasing in recent years. However, although being studied, most of the potential of biochar to be used as a remediating and fertilizing agent is still unclear. Given this, the present work aimed to assess the effect of different concentrations of Cymbopogon citratus (lemongrass) biomass applied to soil contaminated with Cu. Method: Using natural soil, seven treatments were tested, with three replicates each: soil pH 4.7 (T1), soil pH 6.0 (T2), soil pH 6.0, and adding 5 wt.% biochar (T3), soil with 50 mg∙kg-1 Cu (T4), soil at pH 6.0 with 50 mg∙kg-1 Cu (T5), soil with 50 mg∙kg-1 Cu and addition of 5 wt.% biochar (T6) and soil with 50 mg∙kg-1 Cu and addition of 10 wt.% biochar (T7). The treatments were incubated for 30 days in 30 cm³ containers. Afterward, the soil and the leached solution were analyzed. Subsequently, the incubated soil was transferred to recipients, and seedlings of Catharantus roseus were transplanted, totaling twelve plants per treatment. After 60 days, the plants were evaluated according to the biometric parameters of plant size and root size, root volume, and fresh and dry mass of the plant and roots. The contents of macronutrients and Cu in plant tissue were also determined. Results: The data showed that C. citratus biochar acted as a soil acidity-neutralizing agent at 5 wt.% and 10 wt.%. Adding biochar increased all biometric parameters of C. roseus seedlings. Using the biochar also reduced the Cu levels in the plant tissue, although the treatment with 10 wt.% biochar had the highest copper content in the leachate. Conclusion: According to this study, C. citratus biochar has the potential to be used as soil fertilizer and remediating agent. Research Highlights: • Lemongrass biochar was applied in the soil at 5 wt.% and 10 wt.%. • Biochar had a soil acidity-neutralizing property, similar to lime. • The addition of biochar enhanced the growth of Catharantus roseus • Biochar addition reduced Cu uptake by plants, although it increased Cu content in the leachate. • Lemongrass biochar can be envisaged as a potential soil fertilizer and remediating agent.

The use of artificial lighting in a total or supplementary way is a current trend, with growing interest due to the increase in the global population and climate change, which require high-yield, quality, and fast-growing crops with less water and a smaller carbon footprint. This experiment aimed to evaluate the effect of light-emitting diode (LED) lighting on the production of basil, mustard, and red cabbage seedlings under controlled artificial conditions and in a greenhouse as a supplementary lighting regime. Under controlled conditions, the experiment was conducted with basil seedlings, comparing LED light with two wavelengths (purple and white light). In a greenhouse, mustard and red cabbage seedlings were evaluated under natural light (regular photoperiod) and with supplementary purple lighting of 3 h added to the photoperiod. The variables assessed were aerial fresh mass (AFM), aerial dry mass (ADM), root dry mass (RDM), plant length (PL), and leaf area (LA). Basil seedlings grown under purple light showed greater length and AFM than those grown under white light, with no effect on the production of secondary metabolites. In the greenhouse experiment, red cabbage seedlings showed an increase in AFM, ADM, and DRM with light supplementation, with no effect on LA. AFM showed no statistical difference in mustard seedlings, but the productive parameters LA, ADM, and DRM were higher with supplementation. None of the evaluated treatments influenced the production of phenolic compounds and flavonoids in the three species evaluated. Light supplementation affected red cabbage and mustard seedlings differently, promoting better development in some production parameters without affecting the production of phenolic compounds and flavonoids in either plant. Thus, light supplementation or artificial lighting can be considered a tool to enhance and accelerate the growth of seedlings, increasing productivity and maintaining the quality of the secondary metabolites evaluated. Thus, this technology can reduce operational costs, enable cultivation in periods of low natural light and photoperiod, and cultivate tropical species in temperate environments in completely artificial (indoor) conditions.

The production of seedlings is one of the main activities for implementing agricultural crops. Many factors are involved in producing quality seedlings, including nutrition, health, genetics, and climatic factors such as temperature, humidity, and light. To evaluate the effect of light supplementation, a study was conducted using supplementary artificial light to produce lettuce and cauliflower seedlings. Sowing was carried out in styrofoam trays under a floating irrigation system. Part of the experiment containing the two species, received treatment with LED light for an additional 4 h per day, in addition to solar radiation (10 h∙day−1). The remaining seedlings received only solar radiation (without supplementation). After 37 days, the seedlings’ biometric (leaf area, root length, aerial dry mass, and root dry mass) and biochemical parameters (phenolic compounds, flavonoids, chlorophyll a/b, and total chlorophyll) were analyzed. The data showed that the complementary light enhanced the performance in all the biometric parameters evaluated in the experiment for lettuce and cauliflower. The biochemical parameters in lettuce were also higher in seedlings with light supplementation. For cauliflower, supplementary light did not differ from the natural photoperiod for biochemical parameters except for a reduction in the levels of total phenolic compounds. Considering the enhanced biometric and biochemical parameters and greater dry weight and leaf area of the seedlings grown with supplemental light, using such a tool can optimize seedling development, possibly reducing production time in the nursery and providing greater productivity.

Using agricultural gypsum promotes nutrient descent and generates a less aggressive environment for roots, favoring their development and better use of water and nutrients. However, studies on apple trees are scarce, and there is no official recommendation for gypsum application in the soils of southern Brazil. This work aimed to evaluate the potential use of agricultural gypsum to increase soil fertility and apple tree productivity. The research was carried out in the municipality of Ipê, RS, in an apple orchard cv. Condessa planted fifteen years ago and with acidity in the soil layer of 20–40 cm. The design of the experiment was consisted of randomized blocks, containing five treatments and four replications, with 80 m2 each. The treatments consisted of five doses of agricultural gypsum, applied at the beginning of the productive cycle. The study evaluated soil chemical parameters at 0–20 cm and 20–40 cm, chlorophyll content, and crop productivity. The results showed an increase in the sulfur content up to the gypsum dose of 6.0 t∙ha−1 and a reduction in the magnesium content in the soil at both evaluated depths. Agricultural gypsum application did not significantly influence the other chemical parameters evaluated. Chlorophyll content in apple leaves was reduced, and there was an increase in productivity with the increase in the dose of agricultural gypsum. Therefore, gypsum can potentially improve soil fertility and increase apple tree productivity.

Phagocytes maintain homeostasis in a healthy brain. Upon injury, they are essential for repairing damaged tissue, recruiting other immune cells, and releasing cytokines as the first line of defense. However, there seems to be a delicate balance between the beneficial and detrimental effects of their activation in a seizing brain. Blocking the infiltration of peripheral phagocytes (macrophages) or their depletion can partially alleviate epileptic seizures and prevent the death of neurons in experimental models of epilepsy. However, the depletion of resident phagocytes in the brain (microglia) can aggravate disease outcomes. This review describes the role of resident microglia and peripheral infiltrating monocytes in animal models of acutely triggered seizures and epilepsy. Understanding the roles of phagocytes in ictogenesis and the time course of their activation and involvement in epileptogenesis and disease progression can offer us new biomarkers to identify patients at risk of developing epilepsy after a brain insult, as well as provide novel therapeutic targets for treating epilepsy.

Using microorganisms to enhance crop productivity is an active and increasing field of research, which encompasses the productive, environmental, and economic aspects of agricultural production to obtain high-quality crops with a reduction in the need for fertilizers. Among the nutrients necessary for plant growth, phosphorous is problematic due to its low availability and its susceptibility to convert into non-labile forms. In this regard, phosphate-solubilizing bacteria (PSB) can be an interesting tool to improve phosphorous availability and to reduce the requirements of phosphate fertilizers. This work aimed to evaluate the potential use of phosphate-solubilizing bacteria in the supply of phosphorus and soybean development. This study was conducted in the 2019/2020 and 2020/2021 harvests. The experimental design was in randomized blocks, containing seven treatments and six replicates. The treatments consisted of five doses of phosphate fertilization, using triple superphosphate fertilizer, associated with the application of Bacillus subtilis and Bacillus megaterium bacteria, and two treatments, with and without the use of phosphorous fertilizer and without the use of an inoculant. Plant tissue nutrients and biometric and productive parameters of the crop were assessed. According to the observed results, applying PSB associated with phosphate fertilization and phosphate fertilization alone did not influence soybean’s nutritional, biometric, and productive parameters in the two harvests. Thus, the application of B. subtilis and B. megaterium, either associated or not associated with phosphate fertilization, does not contribute to the nutrition, development, and yield of soybean crops in soil with a naturally low P content, considering the climatic and soil conditions of the study.

Mental fatigue is a variation in the psychophysiological state that subjects encounter during or after prolonged cognitive activity periods, affecting top-down attention and cognitive control. The present study aimed to investigate the effects of mental fatigue on attention in the context of the three attention networks according to the Posnerian model (alerting, orienting, and executive networks) by combining the Attentional Network Test (ANT) and event-related potentials technique. Thirty healthy subjects were enrolled in the study. A continuous arithmetic task lasting one hour induced mental fatigue, and EEG recordings were conducted before and after the task while subjects were performing the ANT. The efficiencies of three networks were comparable between groups, while RTs shortened only in the control group and the accuracy related to the alerting and conflict networks declined only after mental effort. Mental fatigue reduced N1 amplitude during alerting network engagement and p3 amplitude during orienting. It also reduced N2 and P3 amplitude during the conflict, particularly the incongruent target-locked response. These findings underscore the covert effects of mental fatigue on attention, suggesting that even in healthy young subjects, compensatory mechanisms may maintain adequate overt performances, but fatigue still has a detrimental effect on top-down attentional mechanisms.

Chagas disease is a public health problem affecting approximately seven million people worldwide. Thus, there is a need to discover drugs for the adequate treatment of this disease because currently available drugs have serious side effects. Therefore, this study aimed to evaluate the in vitro trypanocidal activity of (-)-6,6'-dinitrohinokinin, obtained from the partial synthesis of (-)-hinokinin, on the trypomastigotes and amastigotes forms. For the trypomastigote assay, blood was collected from mice infected with Trypanosoma cruzi through cardiac puncture at the parasitemic peak. The results show that (-)-6,6'-dinitrohinokinin was effective against the trypomastigote forms, presenting an IC50 of 19.83 µM and lysis percentage values ​​of 78.4% and 69.4% at concentrations of 200 and 100 µM, respectively. Molecular docking calculations indicate that (-)-6,6'-dinitrohinokinin favorably interacts with the amino acids present in the active site of the protein trypanothione reductase, a typical target for anti-trypanosomal drug development. According to the results, the (-)-6,6'-dinitrohinokinin showed more significant trypanocidal activity with IC50 of 1.83 µM than benzonidazole positive control with IC50 of 53.2 µM, showing to be a prototype molecule promising for the development of a new antiparasitic drug.

The genus Fridericia belongs to the family Bignoniaceae and comprises 60 species that occur in humid to dry forests, cerrado, and caatinga vegetation. It may be found from Mexico to Argentina and southern Brazil. This article reviews studies conducted on this genus, primarily focusing on its chemical composition and biological activities. Of the 60 known Fridericia species, only 14 have been the object of chemical and biological studies, accounting for 23% of the researched species. Eighty-four compounds, mainly flavonoids, terpenes, xanthones, and phenylethanoids, have been isolated from these species. The biological properties described in this review include antimicrobial, antioxidant, anti-inflammatory, hepatoprotective, antiviral, healing, antiproliferative, trypanocidal, and antileishmania activities. Notably, the species F. chica has been the most studied, as it is listed in the National List of Medicinal Plants of Interest to the Brazilian Unified Health System (RENISUS).

We report the chemical composition of the crude leaf extracts obtained from Stizophyllum perforatum (Cham.) Miers (Bignoniaceae), a simple high-performance liquid chromatography–diode array detection (HPLC-DAD) method based on mangiferin as an internal standard to quantify verbascoside, and the verbascoside acute oral toxicity and antileishmanial activity. HPLC–high-resolution mass spectrometry–DAD (HPLC–HRMS–DAD) analyses of the crude ethanol S. perforatum leaf extracts (CE-1 and CE-2) revealed that verbascoside was the major constituent in both extracts. CE-1 was purified, and verbascoside and casticin, among other compounds, were isolated. The developed HPLC-DAD method was validated and met the required standards. Investigation of the CE-2 acute toxicity indicated a lethal dose (LD50) greater than 2,000 mg/kg of body weight. Both CE-1 and CE-2 exhibited antileishmanial activity. The isolated compounds, verbascoside and casticin, also displayed antileishmanial activity with effective concentrations (IC50) of 6.23 and 24.20 µM against promastigote forms and 3.71 and 18.97 µM against amastigote forms of Leishmania amazonensis, respectively, but they were not cytotoxic to J774A.1 macrophages. Scanning electron microscopy of the L. amazonensis promastigotes showed that the parasites became more rounded and that their plasma membrane was altered in the presence of verbascoside. Additionally, transmission electron microscopy demonstrated that vacuoles emerged, lipids accumulated, kinetoplast size increased, and interstitial extravasation occurred in L. amazonensis promastigotes exposed to verbascoside. These findings suggest that S. perforatum is a promising candidate for further in vivo investigations against L. amazonensis.

Abstract This article presents a literature review on the use of flexible formworks for concrete structures, from their earliest conceptions in the late 19th century to recent applications. The challenges faced by builders, engineers, and architects in designing flexible moulds are discussed. A bibliometric analysis on the subject is also presented. Different methodologies for categorization are analyzed, and a consistent classification based on the application technique is proposed. Advantages and disadvantages of the formwork system are discussed and the article concludes with the perspective of future studies on the construction process through computational models.

Este trabalho buscou investigar uma proposta de Sequência de Ensino Investigativo trabalhada com alunos do 3º ano do Ensino Médio de um Colégio Estadual pertencente a Rede Estadual de Ensino do Estado do Paraná que abordou o tema cargas elétricas. Para esta pesquisa, do tipo qualitativa, optou-se por utilizar como metodologia de análise a Análise Textual Discursiva, cujas categorias a priori foram os eixos estruturantes da Alfabetização Científica e Tecnológica as quais foram identificadas no percurso investigativo. O processo de pesquisa do tipo intervenção pedagógica foi registrado por videogravação e produções textuais onde foi possível evidenciar a elaboração dos conceitos científicos, o entendimento da natureza da ciência e das relações Ciência-Tecnologia e Sociedade e Ambiente, indicando que os estudantes que participaram das atividades propostas se apropriaram dos conhecimentos dentro dos pressupostos da Alfabetização Científica e Tecnológica.

Abstract Schistosomiasis, caused by Schistosoma mansoni Sambon, 1907, is a severe and widely distributed parasitic disease, affecting about 200 million people worldwide. The disease is recognized by elevated mortality rates, especially among those living in areas of poor sanitation. Currently, the chemotherapeutic treatment is solely based on using the praziquantel drug. Therefore, there is a need for the discovery of new medicines for the treatment of this parasitosis. Thus, this work aimed to evaluate the schistosomicidal activity of ethanolic crude extracts from the branches, leaves, flowers, and fruits of Handroanthus impetiginosus (Mart ex DC.) Masttos and characterize its metabolic profile by UPLC-ESI-QTOF analysis. Evaluation of plant extract on S. mansoni was carried out in adult worms in vitro, in which the mortality rate was quantified, and the damages in the tegument of the worms were monitored. All extracts induced changes in the viability of adult males of S. mansoni, causing the death of the parasites, which was directly dependent of the concentration.