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In Mexico, it is not known which institutions use animals for scientific purposes. This work reports, based on data requested from the National Institute of Transparency, Access to Information and Protection of Personal Data (INAI), the types of institutions that use animals for research and how many of these have an ethics committee. Research centres, colleges, hospitals, national institutes, technical colleges, and public universities are the types of institutions that report using animals for experimentation. Only 54% of institutions have ethics committees. Mexican institutions from 2015 to 2021 used a total of 2,112,786 animals. Mammals are the most widely used animal group. The scientific purposes for using animals depend on the type of institution that uses them. In Mexico, it is necessary to update the regulations in order to regulate the use, protection and the care of laboratory animals.

En México se desconoce cuáles son las instituciones que utilizan animales con fines científicos. Se reporta, a partir de datos solicitados al Instituto Nacional de Transparencia, Acceso a la Información y Protección de Datos Personales (INAI), los tipos de instituciones que usan animales y cuántas poseen un comité interno para el cuidado y uso de los animales de laboratorio. Los centros de investigación, colegios, hospitales, institutos nacionales, tecnológicos y universidades públicas son los tipos de instituciones que reportaron usar animales. El 54% de las instituciones poseen comités de ética. Un total de 2,112,786 animales fueron usados por instituciones del 2015 al 2021. Los mamíferos es el grupo animal más utilizado. El uso de los animales se encuentra en función del tipo de institución que los utiliza. En México, es necesario actualizar la normatividad, con el fin de regular el uso, la protección y el cuidado de los animales de laboratorio.

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Wounds represent a growing global issue demanding increased attention. To expedite wound healing, technologies are under development, and light emitting diode (LED) devices of varying wavelengths are being explored for their stimulating influence on the healing process. This article presents a systematic literature review aiming to compile, organize, and analyze the impacts of LED devices on wound healing. This review is registered on the PROSPERO platform [CRD42023403870]. Two blinded authors conducted searches in the Pubmed, Web of Science, Scopus, Embase, and ScienceDirect databases. In vitro and in vivo experimental studies assessing LED utilization in the wound healing process were included. The search yielded 1010 studies, of which 27 were included in the review. It was identified that LED stimulates different healing pathways, promoting enhanced cell proliferation and migration, angiogenesis stimulation, increased collagen deposition, and modulation of the inflammatory response. Thus, it can be concluded that the LED stimulates cellular and molecular processes contingent on the utilized parameters. The effects depend on the standards used. Cell migration and proliferation were better influenced by green and red LED. The extracellular matrix components and angiogenesis were regulated by all wavelengths and the modulation of inflammation was mediated by green, red, and infrared LEDs.

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Zoos are an important repository of animals, which have a wide range of visual systems, providing excellent opportunities to investigate many comparative questions in sensory ecology. However, behavioural testing must be carried out in an animal welfare-friendly manner, which is practical for zoo staff. Here, we present a proof-of-concept study to facilitate behavioural research on the sensory ecology of captive primates. A system consisting of a tablet computer and an automated feeder connected wirelessly was developed and presented to captive primate species to evaluate interactions with and without previous training. A colour stimulus, analogous to the Ishihara test, was used to check the level of interaction with the device, supporting future studies on sensory ecology with zoo animals. Animals were able to use the system successfully and displayed signs of learning to discriminate between the visual stimuli presented. We identified no risk for small primates in their interactions with the experimental setup without the presence of keepers. The use of electronic devices should be approached with caution to prevent accidents, as a standard practice for environmental enrichment for larger animals (e.g., spider monkeys). In the long term, the system developed here will allow us to address complex comparative questions about the functions of different visual systems in captive animals (i.e., dichromatic, trichromatic, etc.).

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Introdução: Cicatrizes visíveis podem acarretar agravos, sejam estéticos, psicológicos, funcionais ou sociais, principalmente de grande extensão e volume, como os queloides. A descoberta de novos tratamentos de queloides não é fácil, visto a presença de alguns entraves metodológicos e éticos, sendo uma área pouco explorada. A toxina botulínica tem sido apresentada como alternativa terapêutica em estudos nacionais e internacionais, sendo necessária uma compilação e destaque dos principais estudos que possam subsidiar a prática clínica. Assim, o objetivo foi apresentar uma revisão de escopo sobre a utilização terapêutica da toxina botulínica para o tratamento de cicatrizes queloides. Método: A revisão foi realizada através da estratégia PICO e utilizando o Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews. Foi realizada nas bases de dados PubMed/ Medline, Biblioteca Virtual em Saúde e SciELO, considerando estudos do período de 2016 até setembro de 2021. Resultados: Foram encontrados 34 artigos no geral relacionados ao tema. Após filtragem e seleção, a revisão foi construída com apoio de 5 artigos. Os estudos variaram entre coorte, relatos de caso, ensaio clínico randomizado e caso-controle. Foi possível observar como principais resultados a ação a curto prazo da toxina botulínica na redução de queloides, maior efetividade na redução dos sintomas e possibilidades de utilização clínica para diferentes populações e manifestações clínicas. Conclusão: O mecanismo de ação da toxina botulínica pode facilitar o tratamento de queloides e redução de sintomas, sendo necessários estudos mais robustos para definição de protocolos cínicos de gestão de cicatrizes.

Introduction: Visible scars can cause problems, whether aesthetic, psychological, functional, or social, mainly of great extension and volume, such as keloids. The discovery of new treatments for keloids is not easy, given the presence of some methodological and ethical obstacles, and it is an area that is little explored. Botulinum toxin has been presented as a therapeutic alternative in national and international studies, requiring a compilation and highlighting of the main studies that can support clinical practice. Thus, the objective was to present a scoping review on the therapeutic use of botulinum toxin for the treatment of keloid scars. Method: The review was carried out using the PICO strategy and using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. It was carried out in the PubMed/ Medline, Virtual Health Library, and SciELO databases, considering studies from 2016 to September 2021. Results: Overall, 34 articles related to the topic were found. After filtering and selection, the review was constructed with the support of 5 articles. The studies varied between cohorts, case reports, randomized clinical trials, and casecontrol. It was possible to observe as main results of the short-term action of botulinum toxin in reducing keloids, greater effectiveness in reducing symptoms, and possibilities of clinical use for different populations and clinical manifestations. Conclusion: The mechanism of action of botulinum toxin can facilitate the treatment of keloids and reduce symptoms, requiring more robust studies to define effective scar management protocols.

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An Adverse Outcome Pathway (AOP) is an analytical model that describes, through a graphical representation, a linear sequence of biologically connected events at different levels of biological organization, causally leading to an adverse effect on human health or the environment. In general, AOPs are constructed based on five central principles: systematic development and review, chemical-agnostic, modular, networks, and living documents. Furthermore, AOPs have the potential to be used, for example, to investigate certain molecular targets; relate the regulation of specific genes or proteins among AOPs; extrapolate biological processes, pathways, or diseases from one species to another; and even predict adverse effects in particular populations. AOPs also emerge as an alternative to animal experimentation in studies of developmental malformations. It's even possible now to develop a quantitative AOP to predict teratogenic effects for some substances. However, the construction of high-quality AOPs requires standardization in the way these models are developed and reviewed, ensuring an adequate degree of flexibility and guaranteeing efficiency. The development of AOPs should strictly be based on the guidance documents developed by the OECD. Nevertheless, an important step for those developing AOPs is the choice of an apical endpoint or an initiating molecular event in order to initiate the construction of the pathway. Another crucial step is a systematic literature review based on the random combination of the blocks of information. With these two fundamental steps completed, it only remains to follow the guidance documents on Developing and Assessing Adverse Outcome Pathways and AOP Developers' Handbook supplement provided by the OECD to organize and construct an AOP. This modern approach will bring radical changes in the field of toxicity testing, regarding the prediction of apical toxic effects using molecular-level effects.

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In Mexico, there are no official public and reliably reported data on the total number and species of non-human animals used for scientific purposes. The aim of the current study was to calculate the total numbers of animals used for scientific and educational purposes in Mexico, from January 2015 to October 2021, based on data requested from the National Institute of Transparency, Access to Information and Protection of Personal Data (INAI, in Spanish). In this period, authorised laboratory animal facilities reported the use of 5,437,263 animals for scientific and educational purposes. However, these data should be viewed with caution, since there is no official register of all Mexican institutions that use animals for these purposes. The use of various species of different taxonomic groups was reported, including mammals, birds, reptiles, amphibians, fish and invertebrates. The main scientific purposes of this animal use were: technological development; innovation; laboratory testing; production of biologicals; quality control; diagnostic purposes; basic and applied research; and education. A robust system for the licensing and approval of animal use, as well as a means to ensure compliance with the relevant regulations, are both urgently required. In addition, in order to regulate animal use, monitor animal care and protect their welfare, the creation of a publicly accessible national database that records the number and species of the animals used is imperative.

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After the implementation of the Arouca Law in Brazil, the use of animals in experimentation and teaching began to be strictly controlled. CEUAs are great allies in reducing the use of animals in experimentation protocols, and although many methods can be replaced, many still need to be validated. The 3R’s (replacement, reduction and refinement) are fundamental for implementing and developing new methodologies. Hyperimmune sera represent a large part of the production of biological products at the Butantan Institute, and the assessment of pyrogenic contamination is an essential test for evaluating new products for registration and release of production batches. Currently, the in vivo pyrogen test is in a transition phase for total replacement of the use of laboratory animals, the same way, the anti-tetanus serum potency test, which presentes an alternative method described in the Brazilian Pharmacopoeia but not yet recognized by CONCEA and not fully accepted by ANVISA for total replacement of the use of animals. The proposed results demonstrate the great national and global interest in reducing and completely replacing the use of animals, therefore traditional methods and alternative methods must be understood according to their applications and limitations.

A partir da implementação da Lei Arouca no Brasil, o uso de animais na experimentação e no ensino começou a ser controlado rigorosamente. As CEUAs são grandes aliadas para redução ao uso de animais nos protocolos de experimentação, e apesar de muitos métodos poderem ser substituídos, muitos ainda precisam ser validados. Os 3R’s (replace, reduction e refinement) são fundamentais para execução e elaboração de novas metodologias. Os soros hiperimunes representam grande parte da produção de produtos biológicos no Instituto Butantan, e a avaliação de contaminação pirogênica é um teste imprescindível para avaliação dos novos produtos para registro e liberação de lotes de produção. Atualmente o teste de pirogênio in vivo está na fase de transição para substituição total ao uso de animais de laboratório, do mesmo modo o teste de potência de soro antitetânico cujo método alternativo já está descrito na Farmacopeia Brasileira mas não está reconhecido pelo CONCEA e não é totalmente aceito pela ANVISA para substituição total ao uso de animais. Os resultados discutidos demostram o grande interesse nacional e mundial para redução e substituição total ao uso de animais, dessa forma os métodos tradicionais e métodos alternativos devem ser compreendidos de acordo com suas aplicações e limitações.

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Experimental research with animals is very important for humanity, as it contributes to discovering new strategies for preventing and treating diseases, developing new surgical techniques, medicines and foods, preceding the final tests that are carried out on the human population. Animal experimentation is fundamental to the advancement of scientific research, as it contributes directly to the development of science and technology. Their contribution helps in the discovery of preventive measures and new treatments for numerous diseases that affect living beings. Examples of scientific contributions through animal studies include the development of vaccines and the production of serums. To establish the protective capacity of serums against the lethal effect of a toxin, potency tests were performed on Swiss mice. This methodology is carried out in the Biological Quality Control routine to release batches of serum produced by the Butantan Institute. The objective of this dissertation is to carry out a critical analysis of the importance and challenges of the use of animals in research.

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Abstract Experimental research with the use of animal models to represent a specific reality is a target of criticism by the population. This study analyzed the knowledge of elementary and high school students on experimental/animal research methods, official ethical guidelines/laws, and regulatory institutions. In total, 35 students answered an informative questionnaire with objective questions about the subject. Only 18 students (Group 1), attended a lecture on the subject. The questionnaire was reapplied to all 35 students. The analysis of the first questionnaire round showed rejection by 51.4% of the students toward the methods used in experimental research. Significant changes in answer patterns between the first and second evaluations were observed, with a decrease in the number of students who strongly disagree with the methods used in experimental research in Group 1 (38.8%) compared to Group 2 (88.2%). These data suggest that educational activities could increase the acceptance of experimental research by the community.

Resumen La investigación experimental en animales para representar una realidad específica es criticada por la población. Este estudio analizó el conocimiento de los alumnos de la primaria y la secundaria sobre los métodos de investigación experimental/animal, los lineamientos/leyes éticas oficiales e instituciones que reglamentan. Un cuestionario con preguntas objetivas sobre el tema fue respondido por 35 alumnos. Solo 18 alumnos (Grupo 1) asistieron a una conferencia sobre el tema. El cuestionario se aplicó nuevamente a 35 alumnos. El primer cuestionario mostró que el 51,4% de los alumnos rechazaban los métodos utilizados en la investigación experimental. Hubo cambios significativos en las respuestas entre la primera y la segunda evaluación, con menor número de alumnos que estaban totalmente en desacuerdo con los métodos de la investigación experimental en el Grupo 1 (38,8%) en comparación con el Grupo 2 (88,2%). Por tanto, las actividades educativas pueden incrementar la aceptación comunitaria de la investigación experimental.

Resumo A pesquisa experimental com uso de modelos animais para representar uma realidade específica é alvo de críticas por parte da população. Este estudo analisou o conhecimento de alunos do ensino fundamental e médio sobre métodos de pesquisa experimental/animal, diretrizes/leis éticas oficiais e instituições reguladoras. Ao todo, 35 alunos responderam a um questionário informativo com perguntas objetivas sobre o assunto. Apenas 18 alunos (Grupo 1) assistiram a uma palestra sobre o tema. O questionário foi aplicado novamente aos 35 alunos. A análise do primeiro questionário mostrou rejeição por 51,4% dos estudantes em relação aos métodos utilizados na pesquisa experimental. Observaram-se mudanças significativas nos padrões de resposta entre a primeira e a segunda avaliação, com diminuição do número de alunos que discordam totalmente dos métodos utilizados na pesquisa experimental no Grupo 1 (38,8%) em relação ao Grupo 2 (88,2%). Esses dados sugerem que atividades educativas podem aumentar a aceitação da pesquisa experimental pela comunidade.

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Aim: This study was performed to compare two different rat defect models (critical calvaria defects versus guided bone regeneration in the mandibular ramus) used to evaluate bone repair in grafted areas. Methods: A total of 12 rats were allocated in two groups according the experimental model used to evaluate the bone repair in grafted areas: a critical sized-calvaria defect of 5 mm filled with bone graft (n=6) and a mandibular ramus filled with the bone graft associated with a Teflon dome-shaped membrane (n=6). Both groups were grafted with deproteinized bovine bone graft. After 60 days, the animals were euthanized and the samples obtained were submitted to histomorphometry analysis to evaluate the relative amount of bone, remaining bone substitute, and soft tissue within the grafted areas. Results: No differences were observed between the preclinical models evaluated in relation to the amount of bone tissue formation (19.93 ± 4.55% in calvaria vs. 21.00 ± 8.20% in mandible). However, there was a smaller amount of soft tissue (43.20 ± 10.97% vs. 57.79 ± 7.61 %; p<0.01) and a greater amount of bone substitute remaining (35.80 ± 5.52% vs. 22.28 ± 4.36 %; p<0.05) in the grafted areas in the mandible compared to calvaria defect. Conclusion: Preclinical models for the analysis of bone repair in grafted areas in the mandible and critical sized-calvaria defects showed different responses in relation to the amount of soft tissue and bone substitute remnants

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Propósito/Contexto. En el presente trabajo se llevará a cabo una reinterpretación de las tres erres (3R) propuestas por William Russell y Rex Burch (reemplazo, reducción y refinamiento), con el objetivo de ampliar su alcance y mejorar las prácticas de experimentación con animales no humanos. Metodología/Enfoque. Se revisará el sentido que le dieron Russell y Burch a las 3R y se evaluará el modo en que cada una de ellas podría redefinirse o complementarse a la luz de las prácticas científicas, las posibilidades técnicas y los conocimientos bioéticos actuales vinculados al uso de animales en investigación. Resultados/Hallazgos. El artículo mostrará que 1) no solo habrían de reemplazarse animales, sino también las ideas equívocas que tenemos, tanto sobre ellos, como sobre la importancia de la educación bioética en la formación científica, 2) que la reducción, además de referirse al número de sujetos utilizados en cada experimento, debería servir para acabar con investigaciones innecesarias, repetitivas y superfluas, así como con algunos persistentes equívocos sobre el modo de operar de la ciencia y 3) que el refinamiento tendría que salir del espacio experimental para extenderse al modo en que pensamos sobre ética animal en el ámbito de la investigación. Discusión/Conclusiones/Contribuciones. El trabajo da cuenta de la importancia que tiene la incorporación del conocimiento bioético contemporáneo en las prácticas de experimentación con animales para mejorar el carácter reflexivo y ético de la ciencia.

Purpose/Background. In the present work, a reinterpretation of the 3Rs (3Rs) proposed by William Russell and Rex Burch (Replacement, Reduction and Refinement) will be carried out with the aim of broadening its scope and improving nonhuman animal experimentation practices. Methodology/Approach. The meaning given by Russell and Burch to the 3Rs will be reviewed and the way in which each of them could be redefined or complemented in the light of current scientific practices, technical possibilities and bioethical knowledge related to the use of animals in research will be evaluated. Results/Findings. The article will show that 1) not only animals should be replaced, but also the misconceptions we have, both about them and about the importance of bioethics education in scientific training, 2) that the reduction, in addition to the number of subjects used in each experiment, should serve to end unnecessary, repetitive and superfluous research, as well as some persistent misconceptions about the way science operates, and 3) that refinement should go beyond the experimental space to extend to the way we think about animal ethics in the research setting. Discussion/Conclusions/Contributions. The paper reports on the importance of incorporating contemporary bioethical knowledge into animal experimentation practices to enhance the reflexive and ethical character of science.

Objetivo/Contexto. Neste documento, uma reinterpretação dos 3Rs (3Rs) propostos por William Russell e Rex Burch (Substituição, Redução e Refinamento) será realizada com o objetivo de ampliar seu escopo e melhorar as práticas não-humanas de testes em animais. Metodologia/ Abordagem. Revisaremos o significado dado por Russell e Burch aos 3Rs e avaliaremos como cada um deles poderia ser redefinido ou complementado à luz das práticas científicas atuais, possibilidades técnicas e conhecimentos bioéticos relacionados ao uso de animais na pesquisa. Resultados/Descobertas. O artigo mostrará que 1) não somente os animais devem ser substituídos, mas também conceitos errôneos sobre eles e a importância da educação bioética no treinamento científico, 2) que a redução, além do número de sujeitos utilizados em cada experimento, deve servir para eliminar pesquisas desnecessárias, repetitivas e supérfluas, assim como alguns conceitos errôneos persistentes sobre a maneira como a ciência funciona, e 3) que o refinamento deve se estender além do espaço experimental para a maneira como pensamos sobre a ética animal na pesquisa. Discussão/Conclusões/Contribuições. O artigo explica a importância de incorporar o conhecimento bioético contemporâneo nas práticas de experimentação animal para realçar o caráter reflexivo e ético da ciência.

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This paper presents results concerning mechanistic modeling to describe the dynamics and interactions between biomass growth, glucose consumption and ethanol production in batch culture fermentation by Kluyveromyces marxianus (K. marxianus). The mathematical model was formulated based on the biological assumptions underlying each variable and is given by a set of three coupled nonlinear first-order Ordinary Differential Equations. The model has ten parameters, and their values were fitted from the experimental data of 17 K. marxianus strains by means of a computational algorithm design in Matlab. The latter allowed us to determine that seven of these parameters share the same value among all the strains, while three parameters concerning biomass maximum growth rate, and ethanol production due to biomass and glucose had specific values for each strain. These values are presented with their corresponding standard error and 95% confidence interval. The goodness of fit of our system was evaluated both qualitatively by in silico experimentation and quantitative by means of the coefficient of determination and the Akaike Information Criterion. Results regarding the fitting capabilities were compared with the classic model given by the logistic, Pirt, and Luedeking-Piret Equations. Further, nonlinear theories were applied to investigate local and global dynamics of the system, the Localization of Compact Invariant Sets Method was applied to determine the so-called localizing domain, i.e., lower and upper bounds for each variable; whilst Lyapunov's stability theories allowed to establish sufficient conditions to ensure asymptotic stability in the nonnegative octant, i.e., R+,03. Finally, the predictive ability of our mechanistic model was explored through several numerical simulations with expected results according to microbiology literature on batch fermentation.

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Las Ciencias Médicas y Biológicas requieren, prioritariamente, que la investigación y la experimentación sean desarrolladas sobre organismos completos (los modelos animales). Su utilización ha permitido desarrollar innumerables ensayos preclínicos para evaluar los mecanismos patógenos y terapéuticos de diversas enfermedades, así como el estudio de las causas, naturaleza y cura de múltiples desórdenes de la salud humana. En este trabajo se muestra una panorámica general de los biomodelos de hipertensión arterial donde se describen: conceptos, características, origen, importancia, utilidad y procedimientos experimentales durante su fase de inducción. También se pondera la justificación de los biomodelos empleados en los estudios preclínicos de esta enfermedad. De igual forma, se describen los antecedentes para medir las alteraciones, las técnicas y los métodos directos e indirectos de medición de la presión arterial, la cual fue provocada experimentalmente en los animales de laboratorio para realizar los estudios de hipertensión humana.

Medical and biological sciences require, as a priority, that research and experimentation be carried out on complete organisms (animal models). Its use has allowed the development of innumerable preclinical tests to evaluate pathogenic and therapeutic mechanisms of various diseases, as well as to study the causes, nature and cure of multiple human health disorders. In this work, we show a general overview of arterial hypertension biomodels where concepts, characteristics, origin, importance, utility and experimental procedures during their induction phase are described. The justification of the biomodels used in preclinical studies of this disease is also considered. Antecedents are also described to measure alterations, techniques and direct and indirect methods of measurement of arterial pressure, which was provoked experimentally in the laboratory animals to carry out the studies of human hypertension.

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Introduction: Soy lecithin has become one of the most widely used dietary supplements with potential to treat obesity. Objective: To determine the effect of soy lecithin on body composition. Material and Methods: An experimental preclinical pharmacology study was carried out in the Laboratory of Antibodies and Experimental Biomodels (Labex-cim) and the Basic Sciences Laboratory of the University of Medical Sciences of Santiago de Cuba in 2019. Soy lecithin was administered for 30 days, in doses considered as maximum and minimum to two experimental groups of Wistar rats, to be compared with the control group that received regular feeding. Bioelectric variables and indicators of fat mass were estimated by establishing differences between the experimental groups using the Kruskal-Wallis test of independent samples and considering the level of significance less than 5 %. Results: Total body water, fat-free mass, extracellular water, and total body fat changed significantly compared to the control and between groups; also, there were variations in fat weight in the main compartments, increasing in the group supplemented at the minimum dose and reducing in the group that received the maximum dose of the product. The phase angle showed reduction in both experimental groups. Conclusions: Soy lecithin, depending on the dose, modifies the body composition in rats, the phase angle being an appreciable parameter for nutritional evaluation.

Introducción: La lecitina de soya se ha convertido en un suplemento dietético de los más utilizados con potencialidades para tratar la obesidad. Objetivo: Determinar el efecto de la lecitina de soya sobre la composición corporal. Material y Métodos: Se realizó un estudio de farmacología preclínica experimental en el Laboratorio de Anticuerpos y Biomodelos Experimentales (Labex-cim) y el Laboratorio de Ciencias Básicas de la Universidad de Ciencias Médicas de Santiago de Cuba, en 2019. Se administró lecitina de soja por 30 días, en dosis consideradas como máximas y mínimas a dos grupos experimentales de ratas Wistar, para ser comparados con grupo control que recibió alimentación habitual. Se estimaron variables bioeléctricas e indicadores de masa grasa estableciendo diferencias entre los grupos experimentales mediante la Prueba de Kruskal-Wallis de muestras independientes y considerando el nivel de significación menor del 5 %. Resultados: El agua corporal total, la masa libre de grasa, el agua extracelular y la grasa corporal total se modificaron de manera significativa en comparación con el control y entre grupos, así como existieron variaciones en el peso de la grasa en los compartimentos principales, incrementándose en el grupo suplementado a dosis mínima y reduciendo en el grupo que recibió dosis máxima del producto. El ángulo de fase mostró reducción en ambos grupos experimentales. Conclusiones: La lecitina de soya, dependiendo de la dosis, modifica la composición corporal en ratas siendo el ángulo de fase un parámetro apreciable para la evaluación nutricional.

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Ultimately, the Mongolian gerbils (Meriones unguiculatus) have acquired a relevant role in biological and biomedical experiments alongside other rodents. The use of gerbils in research has been mainly oriented to physiological and pharmacological studies, with special attention to nervous, digestive, and auditory systems as well as microbiology and parasitology. Ultimately, gerbils have also been applied for studying carcinogenesis in different organs and systems, since these animals show a natural propensity to develop spontaneous proliferative lesions, especially in steroid-responsive organs. This characteristic shed light on the reproductive aspects of this rodent model regarding morphological features in male and female individuals. This review of literature summarizes the significance of this model as an alternative to the use of inbred mice and rats in reproductive experimental research, highlighting recent findings. Gerbils have contributed to the expansion of knowledge in prostate biology in male and female individuals, providing studies related to prostatic morphogenesis and neoplasia. In the testes, spermiogenesis occurs in 15 steps, differently from other experimental models. Also, the complete maturation of the testis-epididymal complex occurs between the second and third months. Mammary gland alterations related to the estrous cycle and pregnancy were described, as well as its modulation under endogenous and exogenous estrogenic compounds. The ovaries frequently present ovarian cysts. Furthermore, this organ shows predominantly interstitial steroidogenic glands in the stroma, especially at aging. Adrenal gland shows a large size compared to other animals, presenting three distinct zones with a remarkable role in steroidogenesis.

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BACKGROUND: Pulmonary congestion is a strong predictor of mortality and cardiovascular events in chronic kidney disease (CKD); however, the effects of the mild form on functionality have not yet been investigated. The objective of this study was to assess the influence of mild pulmonary congestion on diaphragmatic mobility (DM) and activities of daily living (ADL) in hemodialysis (HD) subjects, as well as compare ADL behavior on dialysis and non-dialysis days. In parallel, experimentally induce CKD in mice and analyze the resulting pulmonary and functional repercussions. METHODS: Thirty subjects in HD underwent thoracic and abdominal ultrasonography, anthropometric assessment, lung and kidney function, respiratory muscle strength assessment and symptoms analysis. To measure ADL a triaxial accelerometer was used over seven consecutive days. Twenty male mice were randomized in Control and CKD group. Thoracic ultrasonography, TNF-α analysis in kidney and lung tissue, exploratory behavior and functionality assessments were performed. RESULTS: Mild pulmonary congestion caused a 26.1% decline in DM (R2=.261; P=.004) and 20% reduction in walking time (R2=.200; P=.01), indicating decreases of 2.23mm and 1.54min, respectively, for every unit increase in lung comet-tails. Regarding ADL, subjects exhibited statistically significant differences for standing (P=.002), walking (P=.034) and active time (P=.002), and number of steps taken (P=.01) on days with and without HD. In the experimental model, CKD resulted in increased levels of TNF-α on kidneys (P=.037) and lungs (P=.02), attenuation of exploratory behavior (P=.01) and significant decrease in traveled distance (P=.034). Thoracic ultrasonography of CKD mice showed presence of B-lines. CONCLUSION: The mild pulmonary congestion reduced DM and walking time in subjects undergoing HD. Individuals were less active on dialysis days. Furthermore, the experimental model implies that the presence of pulmonary congestion and inflammation may play a decisive role in the low physical and exploratory performance of CKD mice.

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Abordagens interdisciplinares vêm ganhando maior reconhecimento e destaque nas comunidades de saúde humana e animal, principalmente pela (re)emergência de diversas doenças infecciosas que emanam da interface humano-animal-ambiente. A raiva, zoonose grave, considerada endêmica no Brasil e globalmente negligenciada, é um exemplo. Tanto a vigilância epidemiológica quanto a confirmação dessa doença dependem do diagnóstico laboratorial, que é realizado, frequentemente, por meio dos testes de Imunofluorescência Direta (IFD) e de Isolamento Viral em Camundongo (IVC), via inoculação intracerebral da amostra suspeita em camundongos lactentes ou desmamados. Entretanto, recentemente, a Organização Mundial da Saúde reconheceu a Transcrição Reversa seguida da Reação em Cadeia da Polimerase (RT-PCR) como uma técnica primária válida para esse diagnóstico, podendo ser empregada como alternativa ao uso de animais, evitando sofrimento e morte. Esta dissertação apresenta uma discussão sobre as implicações técnicas e éticas da (não) adoção desse método substitutivo, considerando que todos os animais devem ser respeitados e entendidos como sujeitos singulares em suas percepções do mundo, não como objetos de pesquisa. Esse fato corrobora a necessidade de novas perspectivas que ressignifiquem nossas relações com os animais não humanos, o que é primordial para o estabelecimento de mudanças sistêmicas, de caráter ético-político, que visem o fim da instrumentalização animal e de seu uso no âmbito científico, bem como de qualquer forma de opressão.

Interdisciplinary approaches have been gaining greater recognition and prominence in the human and animal health communities, mainly due to the (re)emergence of several infectious diseases that emanate from the human-animal-environment interface. Rabies is an example, considered a serious zoonosis endemic in Brazil and globally neglected. Both epidemiological surveillance and confirmation of this disease depend on laboratory diagnosis, which is usually performed by the direct fluorescent antibody test (DFAT) and the mouse inoculation test (MIT) via intracranial inoculation of the suspected sample into suckling or weanling mice. However, the World Health Organization recently recognized the reverse transcription polymerase chain reaction (RT-PCR) as a valid primary technique for this diagnosis, which can replace the use of animals, avoiding suffering and death. This study presents a discussion about the technical and ethical implications of (not) adopting this alternative method, considering that all animals must be respected and understood as unique beings with their perceptions of the world, not as objects of research. It also further corroborates the need for new perspectives that reframe our relationships with non-human animals, which is fundamental for the implementation of systemic ethical-political changes, aiming at the end of animal instrumentalization and use in scientific research, as well as all forms of oppression.

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BACKGROUND: Due to the complexity of ruminant digestion, cannulation of organs of the digestive tract has been carried out in order to advance the understanding of digestive physiology, nutrient degradability, gastrointestinal diseases and biotechnological research. The abomasal cannulation is interesting for nutritional studies, especially in suckling calves, to obtain fluid and abomasal content, evaluation of abomasal flow and function, and infusion of nutrients and drugs when it is intended to reach high concentrations in the organ. Conventionally, access and cannulation of digestive organs of ruminants has been performed by laparotomy, a method often criticized and classified as cruel by some sectors related to ethics and animal welfare. The aim of this present study is to describe and standardize a minimally invasive by laparoscopy assisted abomasal cannulation in bovine fetuses (cadavers), which had been previously slaughtered by accident and would be discarded in local slaughterhouses. RESULTS: The abomasal cannulation technique was feasible, simple and did not present major difficulties. The surgical time for cannulation of the abomasum, from the insertion of the trocars to the completion of the technique with fixation of the organ to the abdominal wall, ranged from 9 to 27 min, with an average of 15.5 ± 6.62 min. CONCLUSIONS: The Laproscopic assisted abomasal cannulation in bovine fetuses was feasible and safe with minimal tissue injury to the abdominal wall and with short surgical time. More studies in the clinical routine related to minimally invasive abomasal content collection, abomasopexy and abomasotomy are required in order to demonstrate its impact and importance in bovine clinic.

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Spatial cognition is related to academic achievement in science, technology, engineering, and mathematics (STEM) domains. Neuroimaging studies suggest that brain regions' activation might be related to the general cognitive effort while solving mental rotation tasks (MRT). In this study, we evaluate the mental effort of children performing MRT tasks by measuring brain activation and pupil dilation. We use functional near-infrared spectroscopy (fNIRS) concurrently to collect brain hemodynamic responses from children's prefrontal cortex (PFC) and an Eye-tracking system to measure pupil dilation during MRT. Thirty-two healthy students aged 9-11 participated in this experiment. Behavioral measurements such as task performance on geometry problem-solving tests and MRT scores were also collected. The results were significant positive correlations between the children's MRT and geometry problem-solving test scores. There are also significant positive correlations between dorsolateral PFC (dlPFC) hemodynamic signals and visuospatial task performances (MRT and geometry problem-solving scores). Moreover, we found significant activation in the amplitude of deoxy-Hb variation on the dlPFC and that pupil diameter increased during the MRT, suggesting that both physiological responses are related to mental effort processes during the visuospatial task. Our findings indicate that children with more mental effort under the task performed better. The multimodal approach to monitoring students' mental effort can be of great interest in providing objective feedback on cognitive resource conditions and advancing our comprehension of the neural mechanisms that underlie cognitive effort. Hence, the ability to detect two distinct mental states of rest or activation of children during the MRT could eventually lead to an application for investigating the visuospatial skills of young students using naturalistic educational paradigms.

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This study aimed to survey and analyze the profile of experimental dental research in animals, verifying its trends. We evaluated studies developed with the use of animals in vivo, published in 10 dental journals with high impact factors, from 2015 to 2020. From 1652 studies retrieved, 594 involved in vivo experimentation on animals and were analyzed further. Rats were the species most used and with the highest mean of animals per study. Ferrets, although presenting the lowest rate of publications, had the second highest mean of animals per study. Periodontics was the dental specialty with the highest number of publications, while oral rehabilitation had the lowest number. The data on the institution responsible for reviewing animal research protocols approval, sample size, anesthesia and analgesia were provided in 93.10%, 83%, 70.54% and 23.74% of studies, respectively. In 53% of studies, euthanasia was specified and anesthetic overdose was the method most used. Over the period analyzed, there was a reduction in animal studies in vivo, and periodontics was the specialty that most used this experimental model. Although most studies mentioned approval by an ethics committee, some publications neglected to mention sample size, anesthesia and euthanasia. The omission of essential information may raise scientific and ethical concerns.

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