Teaching and learning pharmacology in Brazil before COVID-19 pandemic: a case study in Rio de Janeiro.

BACKGROUND: Knowledge of pharmacology is crucial for physicians to perform rational and safe medicine. Medical professionals are responsible for prescribing drugs and a weak performace of those can result in medication errors leading to disability, hospitalization, and death, among other situations. It occurs worldwide, including in Brazil, so that learning pharmacology impacts on public health service. We aim to investigate the current pharmacology educational practices in medical schools in the state of Rio de Janeiro, Brazil. METHODS: We surveyed 14 of 22 medical schools in Rio de Janeiro. Pharmacology teachers (n=16) and medical students (n=89) answered a semi-structured questionnaire that included questions about the staff characteristics, pharmacology content, teacher's concepts, and common practices and resources that were used in pharmacology classes. RESULTS: Our results revealed that the medical schools had similar overall curriculums. Pharmacology teachers work more than 30hs a week (75%) and conducted both research and teaching (62.5%). We also found that the multimedia projector was the most common resource (71.9%), and passive pedagogical methodologies (e.g., expository classes) remain a current strategy in pharmacology classes (89.9%). In general, medical students are poorly motivated (55%), which may be related to their performance in assessments. In addition, students believe that pharmacology is a complex (52%) or very complex subject (46%) since for its full understanding the student needs concepts from other disciplines, which can have an impact on the performance and motivation of students. As a result, these medical students do not fully understand the integration between pharmacology's basic concepts and their clinical applications. CONCLUSION: These data seem to demonstrate that the adopted teaching and learning pharmacology strategies and methodologies can be improved in Rio de Janeiro.

Magnetic Nanostructures and Stem Cells for Regenerative Medicine, Application in Liver Diseases.

The term "liver disease" refers to any hepatic condition that leads to tissue damage or altered hepatic function and can be induced by virus infections, autoimmunity, inherited genetic mutations, high consumption of alcohol or drugs, fat accumulation, and cancer. Some types of liver diseases are becoming more frequent worldwide. This can be related to increasing rates of obesity in developed countries, diet changes, higher alcohol intake, and even the coronavirus disease 2019 (COVID-19) pandemic was associated with increased liver disease-related deaths. Although the liver can regenerate, in cases of chronic damage or extensive fibrosis, the recovery of tissue mass is impossible, and a liver transplant is indicated. Because of reduced organ availability, it is necessary to search for alternative bioengineered solutions aiming for a cure or increased life expectancy while a transplant is not possible. Therefore, several groups were studying the possibility of stem cells transplantation as a therapeutic alternative since it is a promising strategy in regenerative medicine for treating various diseases. At the same time, nanotechnological advances can contribute to specifically targeting transplanted cells to injured sites using magnetic nanoparticles. In this review, we summarize multiple magnetic nanostructure-based strategies that are promising for treating liver diseases.

The scientific publication of the Memórias do Instituto Oswaldo Cruz (1909-2020): a history of contribution to the biomedical sciences.

BACKGROUND: The Memórias do Instituto Oswaldo Cruz (MIOC) is one of the first scientific journals created in Brazil and currently one of the most important biomedical journals in South America. Knowledge of the main themes disseminated over time and its main contributors can contribute towards a better understanding of its trajectory and future. OBJECTIVES: Map the journal's scientific publication between 1909 and 2020. METHODS: Data from three scientific databases was combined, alongside bibliometrics and network analysis to analyse publication records between 1909 and 2020. FINDINGS: Publications increased substantially since the 1980s. The main publishing organisations are Brazilian. Excluding Brazil, the main publishing countries are the USA, Argentina, and Colombia. During the entire investigated period, the main themes refer to Chagas disease, schistosomiasis, and Leishmaniasis. During some periods, publications followed disease outbreaks in Brazil (e.g., dengue fever and yellow fever). MAIN CONCLUSIONS: Since its foundation in 1909, the MIOC has focused on infectious and parasitic diseases. The editorial changes implemented from the 1980s onwards led MIOC to a relevant growth concerning annual publications and its transformation into an important communication vehicle for researchers from several Brazilian organisations besides Fiocruz, as well as organisations from other countries, especially within Latin America.

Virtual immunology: an educational software to encourage antigen-antibody interaction learning.

Immunology is a knowledge area of paramount importance in life sciences and health care professional education with diverse applications, as well as for a general public understanding of issues related to vaccination. However, many concepts are complex and difficult to understand based only on conventional classes or static images. The use of tools, such as educational software, may enhance the learning of dynamic molecular phenomena that occur in our bodies. Virtual Immunology is a software that aims to facilitate the learning of certain complex immunology concepts. Herein, we present the "Antigen-antibody interactions" module that was used and evaluated by 127 students and 3 teachers from medical schools from 2 universities, 1 public and 1 private, both in the state of Rio de Janeiro, Brazil. The pretest/posttest research design was used to assess student learning in a randomized sample. To evaluate user perceptions concerning software quality, 14 statements were analyzed using a Likert scale. Results indicate suitable evaluations from both students and teachers concerning the "Antigen-antibody module" as an auxiliary tool in immunology teaching. The software was well rated as an educational resource since it allows dynamically viewing immunological phenomena. In addition, its ease of use and immunological process visualization were the best-evaluated parameters by the students, who recommended this software module as an auxiliary learning tool. The use of the evaluated software may motivate students and aid in the understanding of immunology-related concepts, becoming a complementary tool that may enhance the teaching-learning process.

A processual view on the use of problem-based learning in high school physiology teaching.

In problem-based learning (PBL), the steps and processes present in the PBL tutorial cycle are essential for constructive, self-directed, collaborative, and contextual student learning. This article presents a procedural study of a PBL tutorial cycle with high school students new to the method regarding human respiration and circulation physiology. We observed group dynamics and the learning process that occurred throughout the PBL tutorial cycle. The results indicate that conceptual changes were close to the planned learning objectives and that students enjoyed studying applying PBL. Moreover, a positive correlation was observed between group dynamics, self-directed learning and learning outcomes. Our results provide grounds for restructuring the tutorial cycle, especially important for novice PBL students, such as problem reformulation and the development and diversification of applied learning scaffolds. We conclude that the qualitative analysis performed herein can yield a deeper understanding of the PBL tutorial cycle and may be used to foster PBL implementation in institutions with little experience with the method and monitor its outcomes in organizations with mature PBL use.

Use of an evidence-based health portal to improve teaching and learning in primary care: a mixed methods evaluation.

BACKGROUND: Worldwide, primary care is for most people the gateway into many health systems. Offering solutions to the demands of the communities served requires the constant preparation of professionals, especially doctors and medical undergraduate students. We analyze and propose ways to improve the teaching and learning processes facilitated by the Basic Family Health Units (BFHUs) based on the use of electronic portals with evidence-based medicine criteria. METHOD: First phase: The authors conducted a qualitative-quantitative study on students and instructors of primary care (PC) medicine by administering a survey of open- and closed-ended questions at medical schools. The closed-ended questions were studied with descriptive statistics, and open-ended questions were analyzed via the creation of categories. Perceptions of major teaching and learning problems were then identified. Second phase: Meetings were held with students and their instructors for 6 months and involved the use of electronic portals and the application of new questionnaires using a Likert scale for pre- and postevaluation. RESULTS: In the first phase, 40% of the students considered local instructor training levels a problem. A similar result was found regarding teachers' lectures, revealing a lack of adequate PC training and performance. Building on our results, we focused on BFHUs to apply new strategies for teaching and learning, such as the use of the Evidence-Based Health (SBE) Portal, which includes several databases with clinical evidence criteria. In the second phase, the authors identified an improvement in the quality of learning among instructors and students. This outcome improved safety in daily clinical practice in PC, possibly with better results for its users. CONCLUSIONS: The use of electronic portals can facilitate BFHU teaching and learning and promote the health of users.

Open educational resources in immunology education.

The use of computers as a pedagogical resource is currently on the rise. In the case of immunology, students present difficulties in visualizing molecular phenomena. Thus the use of animations and simulations available on the internet might facilitate the learning of complex immunological concepts. In this context, it is important to map and assess the currently available resources that may be used for educational purposes. This study comprises the search and analysis of educational immunology software freely available on the internet, which can aid students and health professionals in effective learning and continuing education scenarios. A detailed search in English on the existence of free software was carried out on websites and scientific databases. The results clearly indicate a lack of freely available and scientifically validated immunology educational software, despite the existence of several software programs that could be used as auxiliary teaching tools.

Cryopreservation of rat hepatocytes with disaccharides for cell therapy.

Cryopreservation of hepatocytes is a crucial step in the implementation of cell therapy for treating certain liver diseases. In the present study we investigated the effect of the some disaccharides on the cryopreservation of rat hepatocytes. Liver cells were frozen in media in the presence or absence of low concentrations of Me2SO (5% Me2SO) supplemented with varying concentrations of disaccharides (sucrose, glucose and trehalose). After 7 days of cryopreservation, the hepatocytes were thawed and viability was measure by exclusion of trypan blue and by the MTT technique, as well as by determining albumin production. Among the investigated disaccharides and concentrations, 0.2 M trehalose showed the best overall outcome. Compared to the use of Me2SO alone, significant improvement in post-thaw cell viability was observed. The new solution may reduce Me2SO side effects on patients and improve the viability and quality of cryopreserved hepatocytes.

P2X7 receptor as a novel drug delivery system to increase the entrance of hydrophilic drugs into cells during photodynamic therapy.

The second-generation photosensitizer methylene blue (MB) exhibits photochemical and photophysical properties suitable for photodynamic therapy (PDT)-based cancer treatment. However, the clinical application of MB is limited because of its high hydrophilicity, which hinders its penetration into tumor tissues. Therefore, new methods to improve the entry of MB into the cytoplasm of target cells are necessary. Because MB has a mass of 319 Da, transient pores on the plasma membrane, such as the pore induced by the P2X7 receptor (P2X7R) that allows the passage of molecules up to 900 Da, could be used. Using MTT viability assays, flow cytometry experiments, and fluorescence microscopy, we evaluated the toxicity and phototoxicity of MB and potentiation effects of ATP and MB on cell death processes in the J774 cell line (via a P2X7-associated pore). We observed that treatment with 5 µM MB for 15 min promoted the rate of entry of MB into the cytoplasm to 4.7 %. However, treatment with 5 µM MB and 1 mM ATP for the same amount of time increased this rate to 90.2 %. However, this effect was inhibited by pretreatment with a P2X7 antagonist. We used peritoneal macrophages and a cell line that does not express P2X7R as controls. These cells were more resistant to PDT with MB under the same experimental conditions. Taken together, these results suggest the use of the pore associated with P2X7R as a drug delivery system to increase the passage of hydrophilic drugs into cells that express this receptor, thus facilitating PDT.

The P2X7 receptor: shifting from a low- to a high-conductance channel - an enigmatic phenomenon?

The general structure of the P2X7 receptor (P2X7R) is similar to the structure of other P2X receptor family members, with the exception of its C terminus, which is the longest of this family. The P2X7R activates several intracellular signaling cascades, such as the calmodulin, mitogen-activated protein kinase and phospholipase D pathways. At low concentrations of ATP (micromolar range), P2X7R activation opens a cationic channel, similarly to other P2X receptors. However, in the presence of high concentrations of ATP (millimolar range), it opens a pathway that allows the passage of larger organic cations and anions. Here, we discuss both the structural characteristics of P2X7R related to its remarkable functions and the proposed mechanisms, including the dilation of the endogenous pore and the integration of another channel. In addition, we highlight the importance of P2X7R as a therapeutic target.

A new insight into purinergic pharmacology: Three fungal species as natural P2X7R antagonists.

P2X7 is a purinergic receptor involved in important physiological functions and pathological processes, such as inflammation, neurodegeneration, and pain. Despite its relevance, there is no selective antagonist useful in the treatment of diseases related to this receptor. In this context, research for a selective, safe, and potent antagonist compound that can be used in clinical therapy has been growing. In this work, we evaluated the potential antagonistic activity of three fungal extracts, namely, Vishniacozyma victoriae, Metschnikowia australis, and Ascomycota sp., which were discovered in a high-throughput screening campaign to search for new antagonists for P2X7R from natural products. First, the IC50 values of these fungal extracts were determined in J774.G8 (murine macrophage cell line) and U937 (human monocyte cell line) cells through dye uptake assays. The IC50 values of V. victoriae were 2.6 and 0.92 µg/mL, M. australis has IC50 values of 3.8 and 1.5 µg/mL, and Ascomycota sp. showed values of 2.1 and 0.67 µg/mL in J774.G8 and U937 cells, respectively. These extracts also significantly inhibited propidium iodide and Lucifer yellow uptake via P2X7R pore, P2X7R currents in electrophysiology, IL-1ß release, and the production of oxide nitric and reactive oxygen species. The extracts did not cause cytotoxicity within a period of 24 h. The results showed the promising antagonistic activity of these extracts toward P2X7R, thereby indicating that they can be future candidates for phytomedicines with potential clinical applicability.

Structural and molecular modeling features of P2X receptors.

Currently, adenosine 5'-triphosphate (ATP) is recognized as the extracellular messenger that acts through P2 receptors. P2 receptors are divided into two subtypes: P2Y metabotropic receptors and P2X ionotropic receptors, both of which are found in virtually all mammalian cell types studied. Due to the difficulty in studying membrane protein structures by X-ray crystallography or NMR techniques, there is little information about these structures available in the literature. Two structures of the P2X4 receptor in truncated form have been solved by crystallography. Molecular modeling has proven to be an excellent tool for studying ionotropic receptors. Recently, modeling studies carried out on P2X receptors have advanced our knowledge of the P2X receptor structure-function relationships. This review presents a brief history of ion channel structural studies and shows how modeling approaches can be used to address relevant questions about P2X receptors.

A Hybrid Approach Combining Shape-Based and Docking Methods to Identify Novel Potential P2X7 Antagonists from Natural Product Databases.

P2X7 is an ATP-activated purinergic receptor implicated in pro-inflammatory responses. It is associated with the development of several diseases, including inflammatory and neurodegenerative conditions. Although several P2X7 receptor antagonists have recently been reported in the literature, none of them is approved for clinical use. However, the structure of the known antagonists can serve as a scaffold for discovering effective compounds in clinical therapy. This study aimed to propose an improved virtual screening methodology for the identification of novel potential P2X7 receptor antagonists from natural products through the combination of shape-based and docking approaches. First, a shape-based screening was performed based on the structure of JNJ-47965567, a P2X7 antagonist, using two natural product compound databases, MEGx (~5.8 × 103 compounds) and NATx (~32 × 103 compounds). Then, the compounds selected by the proposed shape-based model, with Shape-Tanimoto score values ranging between 0.624 and 0.799, were filtered for drug-like properties. Finally, the compounds that met the drug-like filter criteria were docked into the P2X7 allosteric binding site, using the docking programs GOLD and DockThor. The docking poses with the best score values were submitted to careful visual inspection of the P2X7 allosteric binding site. Based on our established visual inspection criteria, four compounds from the MEGx database and four from the NATx database were finally selected as potential P2X7 receptor antagonists. The selected compounds are structurally different from known P2X7 antagonists, have drug-like properties, and are predicted to interact with key P2X7 allosteric binding pocket residues, including F88, F92, F95, F103, M105, F108, Y295, Y298, and I310. Therefore, the combination of shape-based screening and docking approaches proposed in our study has proven useful in selecting potential novel P2X7 antagonist candidates from natural-product-derived compounds databases. This approach could also be useful for selecting potential inhibitors/antagonists of other receptors and/or biological targets.

Estimating the therapeutic potential of NSAIDs and linoleic acid-isomers supplementation against neuroinflammation.

Nonsteroidal anti-inflammatory drugs (NSAIDs) regulate inflammation, which is associated with their role in preventing neurodegenerative diseases in epidemiological studies. It has sparked interest in their unconventional application for reducing neuroinflammation, opening up new avenues in biomedical research. However, given the pharmacological drawbacks of NSAIDs, the development of formulations with naturally antioxidant/anti-inflammatory dietary fatty acids has been demonstrated to be advantageous for the clinical translation of anti-inflammatory-based therapies. It includes improved blood-brain barrier (BBB) permeability and reduced toxicity. It permits us to speculate about the value of linoleic acid (LA)-isomers in preventing and treating neuroinflammatory diseases compared to NSAIDs. Our research delved into the impact of various factors, such as administration route, dosage, timing of intervention, and BBB permeability, on the efficacy of NSAIDs and LA-isomers in preclinical and clinical settings. We conducted a systematic comparison between NSAIDs and LA-isomers regarding their therapeutic effectiveness, BBB compatibility, and side effects. Additionally, we explored their underlying mechanisms in addressing neuroinflammation. Through our analysis, we've identified challenges and drawn conclusions that could propel advancements in treating neurodegenerative diseases and inform the development of future alternative therapeutic strategies.

A consensus segment in the M2 domain of the hP2X(7) receptor shows ion channel activity in planar lipid bilayers and in biological membranes.

The P2X(7) receptor (P2X(7)R) is an ATP-gated, cation-selective channel permeable to Na(+), K(+) and Ca(2+). This channel has also been associated with the opening of a non-selective pore that allows the flow of large organic ions. However, the biophysical properties of the P2X(7)R have yet to be characterized unequivocally. We investigated a region named ADSEG, which is conserved among all subtypes of P2X receptors (P2XRs). It is located in the M2 domain of hP2X(7)R, which aligns with the H5 signature sequence of potassium channels. We investigated the channel forming ability of ADSEG in artificial planar lipid bilayers and in biological membranes using the cell-attached patch-clamp techniques. ADSEG forms channels, which exhibit a preference for cations. They are voltage independent and show long-term stability in planar lipid bilayers as well as under patch-clamping conditions. The open probability of the ADSEG was similar to that of native P2X(7)R. The conserved part of the M2 domain of P2X(7)R forms ionic channels in planar lipid bilayers and in biological membranes. Its electrophysiological characteristics are similar to those of the whole receptor. Conserved and hydrophobic part of the M2 domain forms ion channels.

Physiological roles and potential therapeutic applications of the P2X7 receptor in inflammation and pain.

The P2X7 receptor (P2X7R) is a nonselective cation channel that is activated by extracellular ATP and triggers the secretion of several proinflammatory substances, such as IL-1ß, IL-18, TNF-α, and nitric oxide. Recently, several preclinical studies have demonstrated that this receptor participates in inflammation and pain mechanisms. Taken together, these results indicate that P2X7R is a promising pharmacological target, and compounds that modulate the function of this receptor show potential as new anti-inflammatory medicines. In this review, we discuss aspects of P2X7R pharmacology and the participation of this protein in inflammation and pain and provide an overview of some promising compounds that have been tested as antagonists of P2X7R, with clinical applicability.

Software for animal randomization: A tool for increasing the reproducibility of science.

Poorly designed preclinical studies may compromise human health due to erroneous conclusions regarding treatment effects in addition to contributing to experimental irreproducibility and wasted resources. Randomization is one of the crucial steps to enhance scientific rigor and is a commonly recognized bias-reducing instrument that increases the reliability and reproduction of studies involving animals (even with syngeneic animals). This procedure should be considered when planning a study and reported during data publication. In this context, this work aimed to highlight the importance of adopting quality measures in preclinical trials, with an emphasis on animal randomization. The 'Mouse Randomization' app was developed to help researchers estimate an adequate sample size to obtain significant statistical power, ensuring the ethical use of animals. This app is freely available on the internet to carry out animal randomization and calculate sample sizes for in vivo experiments. We believe that this brief discussion about animal randomization could raise awareness among researchers on how to improve the quality of preclinical research, increasing reproducibility and avoiding animal misuse.

Development and implementation of a significantly low-cost 3D bioprinter using recycled scrap material.

The field of 3D bioengineering proposes to effectively contribute to the manufacture of artificial multicellular organ/tissues and the understanding of complex cellular mechanisms. In this regard, 3D cell cultures comprise a promising bioengineering possibility for the alternative treatment of organ function loss, potentially improving patient life expectancies. Patients with end-stage disease, for example, could benefit from treatment until organ transplantation or even undergo organ function restoration. Currently, 3D bioprinters can produce tissues such as trachea cartilage or artificial skin. Most low-cost 3D bioprinters are built from fused deposition modeling 3D printer frames modified for the deposition of biologically compatible material, ranging between $13.000,00 and $300.000,00. Furthermore, the cost of consumables should also be considered as they, can range from $3,85 and $100.000,00 per gram, making biomaterials expensive, hindering bioprinting access. In this context, our report describes the first prototype of a significantly low-cost 3D bioprinter built from recycled scrap metal and off-the-shelf electronics. We demonstrate the functionalized process and methodology proof of concept and aim to test it in different biological tissue scaffolds in the future, using affordable materials and open-source methodologies, thus democratizing the state of the art of this technology.

Natural Biopolymers as Additional Tools for Cell Microencapsulation Applied to Cellular Therapy.

One of the limitations in organ, tissue or cellular transplantations is graft rejection. To minimize or prevent this, recipients must make use of immunosuppressive drugs (IS) throughout their entire lives. However, its continuous use generally causes several side effects. Although some IS dose reductions and withdrawal strategies have been employed, many patients do not adapt to these protocols and must return to conventional IS use. Therefore, many studies have been carried out to offer treatments that may avoid IS administration in the long term. A promising strategy is cellular microencapsulation. The possibility of microencapsulating cells originates from the opportunity to use biomaterials that mimic the extracellular matrix. This matrix acts as a support for cell adhesion and the syntheses of new extracellular matrix self-components followed by cell growth and survival. Furthermore, by involving the cells in a polymeric matrix, the matrix acts as an immunoprotective barrier, protecting cells against the recipient's immune system while still allowing essential cell survival molecules to diffuse bilaterally through the polymer matrix pores. In addition, this matrix can be associated with IS, thus diminishing systemic side effects. In this context, this review will address the natural biomaterials currently in use and their importance in cell therapy.