Comparison of two volumes for sciatic perineural injection using 1% methylene blue in rabbit cadavers / [Comparação de dois volumes para injeção perineural no nervo isquiático utilizando azul de metileno 1% em cadáveres de coelhos]

The purpose of this study was to assess the efficacy of a blind technique for sciatic and femoral nerve block in rabbit cadavers by evaluating the spread of 1% methylene blue at two different volumes. Nine recently euthanized rabbits weighing 2.5(0.3kg were used. The sciatic (SN) and femoral (FN) nerves of each limb were randomly assigned for injection with 1% methylene blue at 0.2mL/kg (G0.2) or 0.3mL/kg (G0.3). Nerves were dissected and measured for depth and extension of staining (cm). Mean comparisons were performed using paired t test. The relation between volume and nerve staining ( 2cm was assessed using chi-square test. The mean depth of SN was 1.9±0.2 and 1.6±0.3cm and staining 1.9±1.4 and 2.0±1.2cm, respectively in G0.2 and G0.3. No relation was found between depth and dye spread and there was no association between nerve staining ( 2.0cm and volume of solution. The FN failed to be stained in all subjects. In conclusion, SN injection can be successfully performed without guidance in rabbits. The lower volume (0.2mL/kg) is recommended to avoid systemic toxicity.(AU)

O objetivo deste estudo foi avaliar a eficácia de uma técnica para bloqueio às cegas dos nervos isquiático e femoral em cadáveres de coelhos, por meio da avaliação da dispersão de azul de metileno 1% em dois volumes distintos. Nove coelhos recém-eutanasiados, com peso 2,5(0,3kg, foram utilizados. Os nervos isquiático (NI) e femoral (NF) de cada membro foram aleatoriamente designados para injeção com azul de metileno 1% a 0,2mL/kg (G0,2) ou 0,3mL/kg (G0,3). Em seguida, foram dissecados e mensurados em relação à sua profundidade e extensão corada (cm). As médias foram comparadas por meio de teste t pareado. A relação entre volume e extensão corada ( 2cm foi avaliada utilizando-se teste de qui-quadrado. A profundidade média do NI foi 1,9±0,2 e 1,6±0,3cm, e a extensão corada 1,9±1,4 e 2,0±1,2cm, respectivamente, no G0,2 e no G0,3. Não houve relação entre a profundidade e a extensão corada ou entre a extensão corada ( 2,0cm e o volume de solução. Não foi observada coloração do NF em nenhum cadáver. Concluiu-se que a injeção do NI pode ser realizada com sucesso sem auxílio de tecnologias em coelhos. O menor volume (0,2mL/kg) é recomendado para evitar toxicidade sistêmica.(AU)

Methodological considerations for a model of endodontic treatment in Wistar rats / Consideraciones metodológicas para el modelo de tratamiento endodóntico en ratas Wistar

ABSTRACT The use of correctly designed animal models is a fundamental step prior to clinical trials in humans. Although rats are easy to house and handle, and have molars that resemble those of humans, very few researchers use them as a model for root canal treatment, probably due to their small size and the lack of relevant data necessary to reproduce the model. Our aims were to describe the anatomic and histologic characteristics of the mandibular first molar of the Wistar rat and present a standardised model for its experimental endodontic treatment. Twenty female rats were used. The characteristics of the mesial and distal roots were described histologically and the quality of the results achieved following the treatment protocol presented herein was assessed by means of digital radiographs, micro-CT and histological sections. The age of 55 days was found to be the most adequate for performing this technique, but we consider the interval of 50 to 60 days to be suitable. Both canals are oval, although in opposite planes, and the furcating-facing walls present the minimum dentine thickness. It was essential to become familiar with these aspects in order to decide upon the most appropriate instrumentation and obturation techniques that would enable replication of this model in basic science research.

RESUMEN El uso de modelos animales correctamente diseñados es un paso fundamental previo al desarrollo de ensayos clínicos en humanos. A pesar de resultar fáciles de criar y manipular y de poseer molares que se asemejan a los humanos, muy pocos grupos utilizan a la rata como modelo experimental para el tratamiento endodóntico probablemente debido a su pequeño tamaño y a la escasa información disponible para poder aplicar los modelos existentes. Nuestros objetivos fueron describir las características anatómicas e histológicas del primer molar inferior de la rata Wistar y presentar un modelo estandarizado para el tratamiento endodóntico experimental de esta pieza. Se utilizaron 20 ratas hembra. Las características de las raíces mesial y distal fueron descritas histológicamente y los resultados obtenidos fueron evaluados mediante radiografías digitales, microCTy cortes histológicos. La edad de 55 días demostró ser la más adecuada para ejecutar la técnica, pero consideramos que el intervalo de 50 a 60 días puede resultar apropiado. Se observó que ambos canales presentan una morfología oval, aunque en direcciones opuestas, y que las paredes furcales resultaron ser las que presentan el menor espesor de dentina. Familiarizarse con estos aspectos de la anatomía e histología del molar de la rata resultó fundamental para decidir sobre las técnicas de preparación y obturación más apropiadas que permitieran la replicación de este modelo en el campo de las ciencias básicas.

Structural characteristics of the deciduous teeth of Tibetan miniature pigs / 南方医科大学学报

OBJECTIVE@#To explore the histological structure of the deciduous teeth and the tooth germs of Tibetan miniature pigs for studies of dental tissue diseases and tooth regeneration.@*METHODS@#The structure of the deciduous teeth of Tibetan miniature pigs was observed by X-ray. The ultrastructure of the enamel and dentin of deciduous teeth was characterized by scanning electron microscopy. The jaws and teeth were three-dimensionally reconstructed using Mimics software based on Micro-CT scanning of the deciduous teeth. Image J software was used to calculate the gray value and the mineralization density of the deciduous teeth. Hisotological structure of the tooth germ and the pulp tissue of Tibetan miniature pigs was observed using HE staining.@*RESULTS@#The deciduous teeth of Tibetan miniature pigs were composed of enamel, dentin and medullary pulp tissue. The permanent tooth germ were formed during the deciduous dentition. The enamel and dentin ultrastructure of deciduous teeth were consistent with that of human deciduous teeth. The enamel and dentin mineralization densities were 2.47±0.09 g/cm and 1.72±0.07 g/cm, respectively. The pathological structures of tooth germ and pulp tissue were similar to those of human teeth, and the pulp tissue of the deciduous teeth was in an undifferentiated state.@*CONCLUSIONS@#The deciduous teeth of Tibetan miniature pig have similar anatomy, ultrastructure and histopathological structure to human teeth and can serve as a good animal model for studying human dental tissue diseases and the mechanisms of tooth regeneration.

Laboratory animal welfare: environmental enrichment shows positive effect on animal testing / Bem-estar animal em laboratório: enriquecimento ambiental apresenta efeito positivo na experimentação animal

Reproductive and developmental toxicology has focused on the need to approach the effects of organism exposure to various drugs during pregnancy after the mid-50's, when the thalidomide tragedy stroke humanity. In recent decades, this area of study has developed a lot due to animal testing, raising awareness on the need to improve the quality of life of such animals. Therefore, this paper aims to investigate how the science of animal welfare can improve scientific research as a whole, including the reproductive and developmental toxicology fields, by emphasizing environmental enrichment in animal facilities. To do so, we conducted an integrative literature review on several quantitative and qualitative methodological approaches that are applicable to toxicology studies. Here, we present evidence that environmental enrichment improves animal welfare and prevents or reduces the negative effects of captive housing, which must be a principle of toxicological research for ethical, legal and scientific reasons.(AU)

Na toxicologia da reprodução e do desenvolvimento, a atenção necessária foi dada aos efeitos da exposição do organismo às inúmeras drogas durante o período gestacional somente após a metade dos anos 50, quando a tragédia da talidomida atingiu a humanidade. Assim, esta área alcançou desenvolvimento científico com a contribuição da experimentação animal nas últimas décadas. O uso de animais de laboratórios para a pesquisa científica expôs a necessidade de melhorar a qualidade de vida destas espécies. Portanto, este trabalho tem como objetivo investigar como a ciência do bem-estar animal pode melhorar a pesquisa científica como um todo, incluindo na área de toxicologia da reprodução e de desenvolvimento, enfatizando o enriquecimento ambiental em biotérios. Uma revisão integrativa de literatura foi realizada, incluindo abordagens quantitativas e qualitativas, quais podem ser aplicadas para estudos de toxicologia. Aqui, são mostradas evidências de que o enriquecimento ambiental melhora o bem-estar animal e previne ou reduz os efeitos negativos do cativeiro, qual deve um princípio da pesquisa toxicológica por razões éticas, argumentos legais e garantias científicas.(AU)

Effects of Tianeptine on Adult Rats Following Prenatal Stress

OBJECTIVE: Exposing a pregnant female to stress during the critical period of embryonic fetal brain development increases the risk of psychiatric disorders in the offspring. The objective of this study was to investigate the effect of antidepressant tianeptine on prenatally stressed (PNS) rats. METHODS: In this study, a repeated variable stress paradigm was applied to pregnant rats during the last week of gestation. To investigate the effects of antidepressant tianeptine on PNS rats, behavioral and protein expression analyses were performed. Forced swim test, open field test, and social interaction test were performed to determine changes in PNS rats compared to non-stressed offspring. Haloperidol was used as a positive control as an antipsychotic drug based on previous studies. RESULTS: Behavioral changes were restored after treatment with tianeptine or haloperidol. Western blot and immunohistochemical analyses of the prefrontal cortex revealed downregulation of several neurodevelopmental proteins in PNS rats. After treatment with tianeptine or haloperidol, their expression levels were increased. CONCLUSION: Downregulation of several proteins in PNS rats might have caused subsequent behavioral changes in PNS rats. After tianeptine or haloperidol treatment, behavioral changes in PNS rats were restored. Therefore, tianeptine might decrease incidence of prenatal stress related-psychiatric disorders such as depression and schizophrenia.

The applications and characters of aerosol exposure device for animal HAO Xin-yan, ZHANG Yuan-hui, GAO Hong / 中国医学装备

Aerosol inhalation exposure device provides important means for the studies of respiratory infectious disease, toxicity identification of chemical substance, vaccine evaluation and drug research, and now it is widely used in many fields included of respiratory diseases research, toxicology, inhalation immunity and safety evaluation. It is essential platform to do aerosol infection experiment of using laboratory animal and toxicology studies about inhalation. With the developments of science and technology and for the demand of reality, the device of aerosol exposure is developing in a more safe, efficient, precise and automatic direction, and it has a wide application prospect. Through reviews the characters and applications of inhalation exposure device, this paper will service as the scientific basis and references for further research and selection on the inhalation exposure device in future.

Analysis of proficiency testing results for pathogenic bacteria in laboratory animal in six years / 中国比较医学杂志

Objective To analyze the result of proficiency testing(PT)of detection activities for Laboratory animal pathogenic bacteria in 2011 and 2013-2017. To further improve the detection capacity of laboratory animal testing agency,and promote PT to be carried out in future. Methods During the six years(2011 and 2013 -2017), the National Institutes for Food and Drug Control conducted a total of six(seven projects)PT activities of laboratory animal pathogen bacteria. We analyzed the overall trend and the exposed problems by summarizing the result data of the PT in 6 years. Results A total of 45 laboratories in the country including 20 provinces and cities participated in the PT. The PT projects included Mycoplasma pulmonis, Clostridium piliformis, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella spp.,Klebsiella pneumoniae and Bordetella bronchiseptica. The satisfaction rates were 75%,87.5%,80.0%, 78.6%,93.3,96.2% and 88.0%, respectively. The main reasons of unsatisfactory results were for lack of incubation time,select errors of suspicious bacteria, biochemical identification errors, report writing errors and not timely feedback results. Conclusions The level of domestic laboratory animal pathogenic bacteria detection is gradually increased to achieve the desired goal through continuous proficiency testing activities.

A single person operation procedure and experience of tail vein injection in conscious tree shrews / 中国比较医学杂志

Objective To introduce a single person operation procedure for tail vein injection in conscious tree shrews,and to improve the success rate of injection. Methods The tree shrew was fixed by a canvas glove and a clamp. The tail of the tree shrew was fixed by the operator's left hand, and the drug was injected by the right hand with a 1 mL disposable syringe. Results This method had the advantages of simple operation,economy and practicality,good fixation effect,high matching degree of animals and high success rate of drug administration. Conclusions Compared with other methods,this method has obvious advantages such as single person operation, convenient, time-saving and labor-saving. The cost is low and the effect is good,thus significantly improving the success rate of injection.

An investigation of laboratory animal resources in Guangdong province / 中国比较医学杂志

Objective A state quo survey of laboratory animal resource in Guangdong province is performed to provide reference data for government management decision-making and market assessment of laboratory animals. Methods We used questionnaires focusing on the laboratory animal facilities with authorization by Guangdong Province Government, which mainly included the production and use of laboratory animals,the qualification of employees and the facilities space. Results The total production and use of laboratory animals(except for the eggs)had been increasing in the last four years. 1.57 million laboratory animals were produced and 0.754 million laboratory animals were used in 2016. There were 2352 employees,roughly the same as in 2015. The facilities space for breeding was 121008 m2,and for animal experiment was 73470 m2,which were rising in the past three years. Conclusions In order to reinforce the industry development of laboratory animals in Guangdong province,some suggestions were given in our study,such as facilitating the application of superiority resource including non-human primate and aquatic laboratory animals,supporting the standardization production of several scarce mice and rats, improving relevant employees' overall level and constructing laboratory animal facilities sharing platform.

Design and implementation of laboratory animal expert consultation system / 中国比较医学杂志

A laboratory animal expert consultation system provides an interactive platform for industry experts and users. Based on intelligent mobile terminal used as the application supporter, the platform combines the internet with laboratory animal to share the experts' knowledge, breaks through temporal and spatial restrictions, and resolves other problems such as poor timeliness of inquire service, knowledge data staticization, and irrational exploitation of internet to gain prompt inquire service. The platform would meet the needs of industry users for real-time aids and bridge the gap between industry experts and users. Thus, the transfer of expert' knowledge is realized in pace with the increasing knowledge resource of this platform to accelerate the transformation of theoretical knowledge into the industry. Our study focuses on the system characteristics, the main frame structure, the design of function module and the system implementation.

Reflections on improving the teaching quality of basic surgery / 中华医学教育探索杂志

The Surgery foundation is a course that emphasizes both theory and practice. It is an important part of surgical study and a compulsory basic course for medical students. The teaching quality of this course is directly related to the future level of clinical operation of medical students, and the good teaching methods and means are one of the key factors to determine the quality of the course. In this paper, the reform of teaching means and methods of this course are discussed, so as to further improve the teaching quality and summarize the experience and advice.

Determinación de la documentación del bioterio del Instituto Nacional de Higiene "Rafael Rangel" basado en la norma ISO 9001: 2015 / Determination of the documentation of the biotery National Institute of Hygiene "Rafael Rangel" by norm ISO 9001:2015

Un sistema de gestión de la calidad (SGC) según norma ISO 9001:2015, requiere un soporte documental de sus procesos, que permita a la organización demostrar la eficacia de planificación, operación, control, implantación y mejora continúa de su SGC. La producción de animales de laboratorio (AL) requiere además otros documentos que garanticen las buenas prácticas de producción (BPP). Objetivo: Describir y analizar los procesos del Bioterio definiendo su documentación según la ISO 9001:2015, para apoyar la operatividad, lograr mejoras y recomendar acciones que garanticen la trazabilidad y la satisfacción del cliente. Materiales y métodos: Se hace la descripción del SGC y de BPP diseñado e implantado en la producción de AL bajo condiciones convencionales con barreras. Norma ISO 9001:2015; Mapas y diagramas de procesos, interacciones y documentación nueva y existente. Resultados: Se toma como soporte el enfoque de procesos de la ISO 9001:2015; Levantamiento e Identificación de los procesos claves, clientes y partes interesadas; expectativas y requisitos; Definición de las especificaciones del AL a producir; Descripción de diagramas de flujo asociados en recepción, producción, control y entrega; Mantenimiento de la documentación asociada a la gestión de procesos; planes de control, procedimientos, instructivos y registros. Conclusiones: Producción de AL con la documentación especializada que agrega valor al proceso y al SGC. .La documentación coadyuva la valoración, eficacia y adecuación del SGC. Identifican y controla los procesos claves garantizando su función a satisfacción. Estimula la actitud de mejora en la Institución necesaria para el cambio en la cultura de trabajo

A quality management system (QMS) according to ISO 9001: 2015 standard requires documentary support of this processes, which allows the organization to demonstrate the efficiency of planning, operation, control, implementation and continuous improvement of its QMS. The production of Laboratory Animals (AL) also requires other documents that guarantee good production practices (BPP). Objective: the aim of this study was to describe and analyze the processes of the biotery defining its documentation according to ISO 9001: 2015, to support the operation, achieve improvements and recommend actions that guarantee traceability and customer satisfaction. Materials and methods: The description of the SGC and BPP is designed and implemented in the production of AL under conventional conditions with barriers. The ISO 9001: 2015 standard; Maps and diagrams of processes, interactions and new and existing documentation. Results: The process approach of ISO 9001: 2015 is taken as support; survey and identification of key processes, clients and interested parties; expectations and requirements; definition of the LA specifications to be produced; description of associated flow diagrams in reception, production, control and delivery; maintenance of documentation associated with process management; control plans, procedures, instructions and records. Conclusions: The production of AL with specialized documentation that adds value to the process and the QMS. The documentation contributes to the assessment, effectiveness and adequacy of the QMS. They identify and control the key processes guaranteeing their function to satisfaction and stimulate the attitude of improvement in the Institution necessary for the change in the work culture.

Establishment of Experimental Murine Peritonitis Model with Hog Gastric Mucin for Carbapenem-Resistant Gram-Negative Bacteria / 감염과화학요법

Animal models are essential to studies of infectious diseases. The use of mice to test bacterial infection has been extensively reported. However, methods applied to clinical isolates, particularly for carbapenem-resistant bacteria, must be tailored according to the infection models and bacteria used. In this study, we infected 6-week-old female BALB/c mice intraperitoneally with different strains of resistant bacteria plus 3% hog gastric mucin. This method was found to be efficient and readily applicable for investigation of carbapenem-resisant Gram-negative pathogens (e.g., Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii) detected in Korea.

Use of C57BL/6N mice on the variety of immunological researches / 한국실험동물학회지

Inbred mice are an essential animal strain for research as they can improve the reproducibility and reliability of study results. The establishment of new inbred lines is continuing, and new inbred lines are being used in many research fields. C57BL/6 is a mouse laboratory animal that has been developed and used as an inbred strain since early stage of mouse strain development, and, in the 1950s, C57BL/6 was separated into substrains by the Jackson Laboratory (C57BL/6J) and the National Institutes of Health (C57BL/6N). C57BL/6 mice have been used in immunology and antitumor activity studies since the early strain development stage. After the mouse genome was fully described, C57BL/6 mice use in many areas of research has expanded. In particular, immunological characteristics such as those related to cell-mediated immunity and NK cell activity are relatively higher in C57BL/6 mice than in other mice. The C57BL/6NKorl is a stock of C57BL/6N established as part of a localization of experimental animal strategy of the Korean Food and Drug Administration. Based on analysis of single nucleotide polymorphisms (SNPs), C57BL/6NKorl is considered a genetically distinct inbred stock from other C57BL/6N. Various research efforts have been made to describe the characteristics and increase knowledge of the characteristics of C57BL/6Nkorl. The results obtained through these efforts are expected to increase the utilization of C57BL/6Nkorl as a domestic laboratory animal resource and to enhance the reliability of mouse based studies.

Biosafety hazard of laboratory animals in medical colleges and its prevention and control / 中国比较医学杂志

Biosafety hazard has been paid high attention with increasing use of animal species and quantities in medical colleges. In the present paper, we analyze potential biosafety risks in medical colleges from characteristics of biosafety environment, experiment activity, zoonosis, laboratory animal management, etc. , then give some advices on prevention and control of biosafety hazards.

Management of laboratory animals of new drug safety evaluation in GLP and AAALACi certification systems / 药物评价研究

With the global development of the research of medicine,more and more new drug safety evaluation institutions have been certified by Good Laboratory Practices (GLP) and Association for Assessment and Accreditation of Laboratory Animal Care International (AAALACi).Laboratory animal,which is the carrier of drug safety evaluation,its survival condition and animal welfare will directly effect the experimental results.Dealing with laboratory animal husbandry by scientific methods in two systems is the requirement to make sure the accuracy of experimental data of animal experiments.With the certification processes and practical experiences in two certification systems of Tianjin Institute of Pharmaceutical Research New Drug Evaluation Co.,Ltd.,also accompanied by experience exchangement with peers,the relationship of practices in two certification systems will be preliminarily discussed;Through strengthening the management of laboratory animal,it can help the institutions get the certificates.

Comparison of license issuance and status of administration of Laboratory Animals in Jiangsu and Zhejiang provinces / 中国比较医学杂志

Objective To compare the license issuance and status of administration of laboratory animals in Jiangsu and Zhejiang provinces in the last five years, and to study the status of laboratory animal license management and industry development level in the two provinces.Methods Taking a combination of current status investigation, literature search, information collection and comparative analysis, to study the similarities and differences in the annual issuance of laboratory animal licenses, level of environmental facility, type of institution division, regional distribution of institutions, etc.in the two provinces over the last five years.Results Over the past five years, the total number of the issued laboratory animal licenses and approved institutions in Jiangsu province are significantly more than in Zhejiang province.The proportion of barrier environmental facilities in Jiangsu is slightly higher than that in Zhejiang.Laboratory animal institutions cover most areas of the provinces, relatively concentrated in the capital cities and economically developed cities.The business type institutions account for the highest percentage in the two provinces.Animal species in the two provinces are approximately the same.Conclusions The industrial structure of the laboratory animals in Jiangsu province is more perfect than that in Zhejiang province.Industrialization and socialization get a higher degree in Jiangsu province.The range of regular species of the laboratory animals needs to be further expanded.The competent departments need further optimize and promote license management system of the laboratory animals.

Construction of training evaluation system for laboratory animal practitioners / 中国比较医学杂志

Objective Laboratory animal practitionres need further management through technical and capacity training.Methods Relying on the Laboratory Animal Center of University and its highly qualified faculty, a high-quality training base for laboratory animal practitioners has been set up.Results Based on the relevant laws and regulations about experimental animals, appropriate training outlines, different training books and courses were prepared and organized for different trainees.Focusing on the detailed and exact experiments, training base has put emphasis on the practical ability and operational skills.Conclusions How to regulate the training for laboratory animal practitioner by means of base training is discussed and tried out in this paper.

Biosafety hazard of laboratory animals in medical colleges and its prevention and control / 中国比较医学杂志

Biosafety hazard has been paid high attention with increasing use of animal species and quantities in medical colleges. In the present paper, we analyze potential biosafety risks in medical colleges from characteristics of biosafety environment, experiment activity, zoonosis, laboratory animal management, etc. , then give some advices on prevention and control of biosafety hazards.

Investigation and analysis of laboratory animal waste disposal in Beijing area in 2016 / 中国比较医学杂志

Objective To investigate the treatment and disposal of laboratory animal waste in Beijing area in 2016. Methods Questionnaire, telephone survey, on-the-spot investigation and WeChat were used to survey the basic situation and laboratory animal waste management, including bedding material, excreta, carcasses and experimental consumables,etc. in 164 laboratory animal facilities in Beijing area in 2016. Results The data we have collected were relatively comprehensive and universal, reflecting the currently existing problems. Conclusions This investigation provides a reference for the compilation of the management rules of laboratory animal waste in Beijing.