Un ambiente de aprendizaje como propuesta para la enseñanza de las matemáticas

Presentamos los resultados de la aplicación de un cuestionario sobre actitudes hacia las matemáticas, como primera fase en la construcción de un ambiente de aprendizaje. El estudio se llevó a cabo en una escuela de nivel medio superior perteneciente al Instituto Politécnico Nacional (IPN) en la Ciudad de México. El análisis de las respuestas, se efectuó estadísticamente con el software STATA y se contrastaron con el promedio de calificaciones obtenidas en tres evaluaciones escritas. La postura que hemos adoptado es desde la investigación acción, participando un equipo de cinco profesores de distintas escuelas y asignaturas y estudiantes de quinto semestre del nivel medio superior. Así obtuvimos evidencia de las actitudes que presentan los estudiantes, sirviéndonos esta información para presentarles opciones y elaborar estrategias, como parte de nuestro ambiente de aprendizaje

Nuevas aproximaciones de vigilancia de transmisión de Mycobacterium tuberculosis en entornos comunitarios complejos y de otros patógenos relevantes en el entorno nosocomial

La caracterización molecular y genómica ha transformado el modo en el que abordamos las dinámicas de transmisión de microorganismos patógenos. Sin embargo, son necesarios nuevos esfuerzos para definir el modo más adecuado de integrar estas aproximaciones en el análisis de diferentes retos epidemiológicos. Con este fin, en esta tesis se han definido dos bloques de trabajo, atendiendo a infecciones i) de carácter comunitario, seleccionando a M. tuberculosis como patógeno de alta relevancia global y ii) de naturaleza nosocomial, enfocándonos en M. chimaera, como patógeno responsable del problema emergente derivado de la exposición a dispositivos contaminados, y en P. aeruginosa MDR, microorganismo de gran relevancia en brotes que implican transmisión persona-persona. En el primer bloque, abordamos la caracterización de la transmisión transfronteriza de TB multirresistente (TB-MDR) entre Perú, España e Italia. El análisis por MIRU-VNTR reveló una elevada tasa de transmisión reciente de TB-MDR en Perú. La caracterización por WGS determinó con precisión la existencia de dos eventos de exportación intercontinental de TB-MDR desde Perú a Europa, que implicaban a dos variantes de cepas circulantes en Perú, con transmisión posterior en Europa. El estudio integrado entre Perú y Europa reveló la necesidad de realizar esfuerzos transnacionales para abordar la transmisión de TB-MDR. Lamentablemente, son numerosos los países de origen de migrantes que carecen de sistemas de epidemiología molecular sistemática. Tratando de compensar esta brecha de conocimiento, desarrollamos una estrategia alternativa basada en i) genotipado por MIRU-VNTR, ii) caracterización por WGS de los clusters prevalentes para identificar SNPs de cepa y iii) desarrollo de PCRs específicas, que simplificaran su vigilancia prospectiva. Esta estrategia se pilotó en Panamá sobre una colección de cepas de dos provincias (Panamá y Colón). El analisis reveló una alta proporción (50%) de aislados de MTB agrupados en cluster. El análisis por WGS permitió diferenciar cepas de transmisión reciente de cepas prevalentes. El diseño de tres PCRs especificas permitió la vigilancia prospectiva in situ de estas cepas, responsables de un tercio del total de casos de TB. Una de las cepas prevalentes en Colón correspondió al linaje Beijing, y es responsable del 57% de los casos incidentes. Su estudio filogenético permitió determinar que pertenece a un sublinaje Beijing moderno (Bmyc13, L2.2.5), y que su posible entrada a Panamá (2000 y 2012 constituye el período más probable) pudo ocurrir desde Vietnam, Dada la rentabilidad en el estudio de la transmisión de TB de la aplicación combinada de genotipado, WGS y PCRs específicas de cepas, era oportuno evaluar su transferibilidad al terreno de las infecciones nosocomiales. Para ello, replicamos el esquema de trabajo en TB a la caracterización de una sospecha de brote por P. aeruginosa XDR. El análisis por WGS y la consiguiente PCR específica, permitió descartar casos no relacionados, e identificar casos nuevos que no habían sido sospechados. Además, definió la existencia de brotes solapantes de menor dimensión, permitió determinar el verdadero caso índice, y finalmente, alertar de que el brote se mantenía aún activo en el momento del análisis. Por último, la reciente alarma global derivada de la exposición de pacientes a dispositivos “Heater-cooler” (HCU) contaminados con M. chimaera justificó nuestra atención sobre este patógeno. Aplicamos una PCR en tiempo real específica con el fin de: i) optimizar la vigilancia ambiental prospectiva de los HCU e ii) identificar retrospectivamente casos que hubieran pasado desapercibidos. La estrategia mostró su utilidad para la identificación precoz de dispositivos HCU contaminados, permitiendo su monitorización y desveló la infección por M. chimaera en un paciente que había sido sometido a cirugía cardíaca en una institución diferente a la nuestra. El estudio por WGS del aislado del paciente y de los obtenidos de los dispositivos contaminados, permitió demostrar la participación de la cepa responsable del brote global

虚拟电磁实验室在工程学中的教学策略: 使用情境学习方法

Virtual laboratories (VL) have had a special interest in recent years in which immersive education is attractive to students and complements the teaching and learning processes in institutions of diverse educational levels. Although there are several types of virtual laboratories used at various educational levels, there are important challenges for their design as an ad-hoc didactic strategy. One of the main difficulties in the application of educational technology is having virtual educational environments especially dedicated to the areas of engineering, which not only present interactive practical sessions where animations are manipulated, but also encourage the metacognitive analysis of the students; in order to build an autonomous and reflective learning through educational approaches that accompany educational innovation through new technologies. This article presents the design and implementation of a Virtual Laboratory of Electromagnetism (VLE) as a didactic strategy under the situated learning approach, remotely applied to university engineering students through portable versions of the didactic tool designed with Unity® in a public university of Mexico. This research describes the context of the case study, the methodology to identify the criteria under the approach of the situated learning educational model suggested for the development of the virtual environment, the characteristics of the design through animation software, and the educational intervention implemented at the university education level. Finally, an analysis of the results obtained after the application of the laboratory is carried out by studying the perception of the university community through exit surveys.Los laboratorios virtuales (LV) han tenido un especial interés en los últimos años en que la educación inmersiva resulta atractiva para los estudiantes y complementa los procesos de enseñanza y aprendizaje en las instituciones de diversos niveles educativos. Aunque existen varios tipos de laboratorios virtuales utilizados en diversos niveles educativos, existen importantes retos para el diseño de estos como estrategia didáctica ad-hoc. Una de las principales dificultades en la aplicación de tecnología educativa es contar con entornos educativos virtuales especialmente dedicados a las áreas de ingeniería, que no sólo presenten prácticas interactivas donde se manipulen las animaciones, sino que fomenten el análisis metacognitivo de los estudiantes; para así construir un aprendizaje autónomo y reflexivo a través de enfoques educativos que acompañen la innovación educativa a través de las nuevas tecnologías. Este artículo presenta el diseño e implementación de un Laboratorio Virtual de Electromagnetismo (LVE) como estrategia didáctica bajo el enfoque de aprendizaje situado, aplicado a estudiantes universitarios de ingeniería de manera remota a través de versiones portátiles de la herramienta didáctica diseñada con Unity® en una universidad pública de México. En esta investigación se describe el contexto del caso de estudio, la metodología para identificar los criterios bajo el enfoque del modelo educativo de aprendizaje situado sugerido para el desarrollo del entorno virtual, las características del diseño a través del software de animación y la intervención educativa implementada en el nivel de educación superior. Finalmente, se realiza un análisis de los resultados obtenidos después de la aplicación del laboratorio mediante el estudio de la percepción de la comunidad universitaria a través de encuestas de salida.Виртуальные лаборатории вызывают особый интерес в последние годы, поскольку иммерсивное образование привлекательно для студентов и дополняет процессы преподавания и обучения в учебных заведениях на различных уровнях образования. Хотя существует несколько типов виртуальных лабораторий, используемых на различных уровнях образования, существуют значительные трудности при их разработке в качестве специальной дидактической стратегии. Одной из основных трудностей в применении образовательных технологий является создание виртуальной образовательной среды, специально предназначенной для инженерных областей, которая не только представляет интерактивные практики, где манипулируют анимацией, но и поощряет метакогнитивный анализ студентов; для того, чтобы построить автономное и рефлексивное обучение с помощью образовательных подходов, которые сопровождают образовательные инновации с помощью новых технологий. В данной статье представлена разработка и внедрение виртуальной лаборатории электромагнетизма в качестве дидактической стратегии в рамках метода обучения на месте, применяемого к студентам инженерных специальностей университетов дистанционно с помощью портативных версий дидактического инструмента, разработанного с помощью Unity® в государственном университете Мексики. В данном исследовании описывается контекст ситуационного исследования, методология определения критериев в рамках образовательной модели обучения на месте, предложенной для разработки виртуальной среды, характеристики дизайна с помощью анимационного программного обеспечения и образовательное вмешательство, реализованное на уровне высшего образования. Наконец, проводится анализ результатов, полученных после применения лаборатории, путем изучения восприятия университетского сообщества с помощью опросов на выходе.近年来，虚拟实验室特别引人注目，因其沉浸式教育对学生具有吸引力，并补充了不同教育水平机构的教学和学习过程。尽管在不同的教育水平上可以使用不同类型的虚拟实验室，但在将它们设计为临时教学策略方面仍存在重大挑战。教育技术应用的主要困难之一是拥有专门针对工程领域的虚拟教育环境，不仅提供动画操作的交互实践，还鼓励学生进行元认知分析；通过新技术伴随教育创新的教育方法来建立自主和反思性学习。本文介绍了虚拟电磁实验室的设计和实施，作为情境学习方法下的一种教学策略，通过墨西哥公立大学使用 Unity® 设计的教学工具的便携式版本远程应用于大学工程专业的学生。本研究描述了案例研究的背景、在情境学习教育模型方法下确定标准的方法，为在高等教育层面的虚拟环境的发展提出了建议，通过动画软件设计的特征以及实施的教育干预。最后，通过研究末问卷研究大学社区对其感知，对实验室申请后获得的结果进行分析

De la situación a-didáctica a la situación didáctica, el caso de la ENIGH 2016, en estudiantes de nivel superior

La introducción de la estadística en el currículum de carreras de ingeniería se ve ponderado por su amplia aplicación en el análisis e interpretación de datos, así como los procedimientos requeridos en la centralización y dispersión de éstos. Además de un curso introductorio hacia la probabilidad. En el perfil del desarrollo del pensamiento estadístico, se propone la enseñanza de la estadística a través de proyectos (Díaz, C., Arteaga, P. y Batanero, C. 2008; MacGillivray y Pereira-Mendoza, 2011). Así mismo la propuesta de metodologías de enseñanza de la comunidad de educadores estadísticos, basadas en competencias, lo que permitirá que el estudiante se de cuenta de su importancia en diferentes ámbitos disciplinares

Avian Mycobacteriosis in a Rescued Harpy Eagle from Darien Forest, Panama

Background: The Harpy eagle (Harpia harpyia) is the largest raptor in the Neotropical region, distributed in low densities within primary forest habitats from southern Mexico to east-central Brazil, including Central America and Panama. Although locally extinct due to habitat degradation, human poaching and reduction of tropical forests in recent decades, some remnant populations are known to be small and isolated. Thus, information on its ecology, including infectious diseases, is critical for conservation efforts and management of populations of this emblematic species in the wild. Avian Mycobacteriosis (AM) is a chronic disease affecting a wide range of birds and mammals and clinical cases have been sporadically reported, although in harpy eagles, has not been documented. In addition, scant information exists on pathologies affecting raptors, therefore, this report expands the knowledge on infectious diseases affecting wild birds. This study describes the first case of AM in an immature harpy eagle rescued from Darien gap and presents details of the clinical manifestation of the disease and its histological findings. Case: An immature harpy eagle was presented to a rescue center after being confiscated by Ministry of Environment from a local farm in a remote region of Eastern Panama, in the Darien gap. The raptor had a history of having been kept in captivity for approximately five weeks, cohabiting with backyard poultry and fed corn, raw duck and chicken provided by farm owners. Stagnant water was offered for drinking. The harpy eagle arrived to the facility very lethargic and emaciated. Physical examination revealed damaged plumage, poor body condition and dyspnea. Complete blood count revealed anemia and leukocytosis based on lymphocytosis and eosinophilia. Biochemical profile evidenced an increased level of aspartate aminotransferase (AST), phosphorus and total plasma protein. Most remarkable radiographic findings were splenomegaly, hepatomegaly and increased opacity in kidneys, intestines, and aerial sacs. None of the other diagnostic tests performed were conclusive, like tracheal, esophageal and cloacal cultures for fungal infection and fecal exam. After one week of treatment, it showed a remarkable recovery, but at the end of the second week, declined dramatically, dying in the third week of treatment. Post-mortem examination revealed the presence of diffuse granulomas in multiple organs. Histologic examination with gram and Ziehl Neelsen staining revealed the presence of gram-positive and acid-fast bacteria, compatible with Mycobacterium-like bacilli. PCR-restriction fragment length polymorphism analysis of the hsp65, digested with BstEII and HaEIII restriction enzymes confirmed the presence Mycobacterium avium complex in tissues samples. Discussion: This is the first report of AM in a harpy eagle, presenting an extreme emaciation with dyspnea, abnormalities in spleen, liver and air sacs. Biochemical and hematological parameters revealed alterations consistent with infection and organ malfunctions in liver, but Mycobacteriosis was not suspected initially and it was necessary to support the diagnosis with histopathological studies and DNA amplification for a proper identification of the disease. This allowed us to confirm that ante-mortem clinical diagnosis of Avian Mycobacteriosis can be challenging, especially in birds who usually show non-specific signs of the disease and external lesions are not commonly observed. Further studies are requiring to determine the characteristics and clinical signs of this disease in this and other raptors. Also, to determine the source of infection affecting raptors and other protected species in the Neotropical region, especially for diseases with relevance in the conservation of birds and animal health control.Background: The Harpy eagle (Harpia harpyia) is the largest raptor in the Neotropical region, distributed in low densities within primary forest habitats from southern Mexico to east-central Brazil, including Central America and Panama. Although locally extinct due to habitat degradation, human poaching and reduction of tropical forests in recent decades, some remnant populations are known to be small and isolated. Thus, information on its ecology, including infectious diseases, is critical for conservation efforts and management of populations of this emblematic species in the wild. Avian Mycobacteriosis (AM) is a chronic disease affecting a wide range of birds and mammals and clinical cases have been sporadically reported, although in harpy eagles, has not been documented. In addition, scant information exists on pathologies affecting raptors, therefore, this report expands the knowledge on infectious diseases affecting wild birds. This study describes the first case of AM in an immature harpy eagle rescued from Darien gap and presents details of the clinical manifestation of the disease and its histological findings. Case: An immature harpy eagle was presented to a rescue center after being confiscated by Ministry of Environment from a local farm in a remote region of Eastern Panama, in the Darien gap. The raptor had a history of having been kept in captivity for approximately five weeks, cohabiting with backyard poultry and fed corn, raw duck and chicken provided by farm owners. Stagnant water was offered for drinking. The harpy eagle arrived to the facility very lethargic and emaciated. Physical examination revealed damaged plumage, poor body condition and dyspnea. Complete blood count revealed anemia and leukocytosis based on lymphocytosis and eosinophilia. Biochemical profile evidenced an increased level of aspartate aminotransferase (AST), phosphorus and total plasma protein. Most remarkable radiographic findings were splenomegaly, hepatomegaly and increased opacity in kidneys, intestines, and aerial sacs. None of the other diagnostic tests performed were conclusive, like tracheal, esophageal and cloacal cultures for fungal infection and fecal exam. After one week of treatment, it showed a remarkable recovery, but at the end of the second week, declined dramatically, dying in the third week of treatment. Post-mortem examination revealed the presence of diffuse granulomas in multiple organs. Histologic examination with gram and Ziehl Neelsen staining revealed the presence of gram-positive and acid-fast bacteria, compatible with Mycobacterium-like bacilli. PCR-restriction fragment length polymorphism analysis of the hsp65, digested with BstEII and HaEIII restriction enzymes confirmed the presence Mycobacterium avium complex in tissues samples. Discussion: This is the first report of AM in a harpy eagle, presenting an extreme emaciation with dyspnea, abnormalities in spleen, liver and air sacs. Biochemical and hematological parameters revealed alterations consistent with infection and organ malfunctions in liver, but Mycobacteriosis was not suspected initially and it was necessary to support the diagnosis with histopathological studies and DNA amplification for a proper identification of the disease. This allowed us to confirm that ante-mortem clinical diagnosis of Avian Mycobacteriosis can be challenging, especially in birds who usually show non-specific signs of the disease and external lesions are not commonly observed. Further studies are requiring to determine the characteristics and clinical signs of this disease in this and other raptors. Also, to determine the source of infection affecting raptors and other protected species in the Neotropical region, especially for diseases with relevance in the conservation of birds and animal health control

Simplified Model to Survey Tuberculosis Transmission in Countries Without Systematic Molecular Epidemiology Programs

Systematic molecular/genomic epidemiology studies for tuberculosis surveillance cannot be implemented in many countries. We selected Panama as a model for an alternative strategy. Mycobacterial interspersed repetitive unit–variable-number tandem-repeat (MIRU-VNTR) analysis revealed a high proportion (50%) of Mycobacterium tuberculosis isolates included in 6 clusters (A–F) in 2 provinces (Panama and Colon). Cluster A corresponded to the Beijing sublineage. Whole-genome sequencing (WGS) differentiated clusters due to active recent transmission, with low single-nucleotide polymorphism–based diversity (cluster C), from clusters involving long-term prevalent strains with higher diversity (clusters A, B). Prospective application in Panama of 3 tailored strain–specific PCRs targeting marker single-nucleotide polymorphisms identified from WGS data revealed that 31.4% of incident cases involved strains A–C and that the Beijing strain was highly represented and restricted mainly to Colon. Rational integration of MIRU-VNTR, WGS, and tailored strain–specific PCRs could be a new model for tuberculosis surveillance in countries without molecular/genomic epidemiology programsSystematic molecular/genomic epidemiology studies for tuberculosis surveillance cannot be implemented in many countries. We selected Panama as a model for an alternative strategy. Mycobacterial interspersed repetitive unit–variable-number tandem-repeat (MIRU-VNTR) analysis revealed a high proportion (50%) of Mycobacterium tuberculosis isolates included in 6 clusters (A–F) in 2 provinces (Panama and Colon). Cluster A corresponded to the Beijing sublineage. Whole-genome sequencing (WGS) differentiated clusters due to active recent transmission, with low single-nucleotide polymorphism–based diversity (cluster C), from clusters involving long-term prevalent strains with higher diversity (clusters A, B). Prospective application in Panama of 3 tailored strain–specific PCRs targeting marker single-nucleotide polymorphisms identified from WGS data revealed that 31.4% of incident cases involved strains A–C and that the Beijing strain was highly represented and restricted mainly to Colon. Rational integration of MIRU-VNTR, WGS, and tailored strain–specific PCRs could be a new model for tuberculosis surveillance in countries without molecular/genomic epidemiology program

Suitability of a probability course in the career of telematics in an engineering school of the National Polytechnic Institute

III Congreso Internacional Virtual de Educación Estadística (CIVEEST), 21-24 febrero de 2019. [www.ugr.es/local/fqm126/civeest.html]Particularmente en la malla curricular de la carrera de ingeniería en telemática, de una escuela perteneciente al Instituto Politécnico Nacional en la Ciudad de México; se presentan dificultades en los estudiantes al tener una gran cantidad de contenido matemático, en particular de la teoría de probabilidad, en las unidades de aprendizaje: teoría de comunicaciones, sistemas celulares, telefonía, comunicaciones digitales, transmisión de datos y teoría de la información. En esta investigación, a través de un trabajo interdisciplinar, abordamos el contenido probabilístico con problemas tipo de las diversas unidades de aprendizaje en cuestión. Para la elaboración de las prácticas, estamos tomando en cuenta el constructo teórico de la idoneidad didáctica con sus dimensiones para posteriormente analizar su implementación.In the engineering career in telematics, of a school belonging to the National Polytechnic Institute in Mexico City, students have difficulties due to the large amount of mathematical content, particularly probabilistic content, in the learning units: communication theory, cellular systems, telephony, among others. In this research, through an interdisciplinary work, we address the probabilistic content with typical problems of the different learning units. For the elaboration of the practices, we are taking into account the theoretical construct of didactic suitability, with its dimensions, to later analyze its implementation

Avian Mycobacteriosis in a Rescued Harpy Eagle from Darien Forest, Panama

The Harpy eagle (Harpia harpyia) is the largest raptor in the Neotropical region, distributed in low densities within primary forest habitats from southern Mexico to east-central Brazil, including Central America and Panama. Although locally extinct due to habitat degradation, human poaching and reduction of tropical forests in recent decades, some remnant populations are known to be small and isolated. Thus, information on its ecology, including infectious diseases, is critical for conservation efforts and management of populations of this emblematic species in the wild. Avian Mycobacteriosis (AM) is a chronic disease affecting a wide range of birds and mammals and clinical cases have been sporadically reported, although in harpy eagles, has not been documented. In addition, scant information exists on pathologies affecting raptors, therefore, this report expands the knowledge on infectious diseases affecting wild birds. This study describes the first case of AM in an immature harpy eagle rescued from Darien gap and presents details of the clinical manifestation of the disease and its histological findings.The Harpy eagle (Harpia harpyia) is the largest raptor in the Neotropical region, distributed in low densities within primary forest habitats from southern Mexico to east-central Brazil, including Central America and Panama. Although locally extinct due to habitat degradation, human poaching and reduction of tropical forests in recent decades, some remnant populations are known to be small and isolated. Thus, information on its ecology, including infectious diseases, is critical for conservation efforts and management of populations of this emblematic species in the wild. Avian Mycobacteriosis (AM) is a chronic disease affecting a wide range of birds and mammals and clinical cases have been sporadically reported, although in harpy eagles, has not been documented. In addition, scant information exists on pathologies affecting raptors, therefore, this report expands the knowledge on infectious diseases affecting wild birds. This study describes the first case of AM in an immature harpy eagle rescued from Darien gap and presents details of the clinical manifestation of the disease and its histological findings

Simplified Model to Survey Tuberculosis Transmission in Countries Without Systematic Molecular Epidemiology Programs

Systematic molecular/genomic epidemiology studies for tuberculosis surveillance cannot be implemented in many countries. We selected Panama as a model for an alternative strategy. Mycobacterial interspersed repetitive unit–variable-number tandem-repeat (MIRU-VNTR) analysis revealed a high proportion (50%) of Mycobacterium tuberculosis isolates included in 6 clusters (A–F) in 2 provinces (Panama and Colon). Cluster A corresponded to the Beijing sublineage. Whole-genome sequencing (WGS) differentiated clusters due to active recent transmission, with low single-nucleotide polymorphism–based diversity (cluster C), from clusters involving long-term prevalent strains with higher diversity (clusters A, B). Prospective application in Panama of 3 tailored strain–specific PCRs targeting marker single-nucleotide polymorphisms identified from WGS data revealed that 31.4% of incident cases involved strains A–C and that the Beijing strain was highly represented and restricted mainly to Colon. Rational integration of MIRU-VNTR, WGS, and tailored strain–specific PCRs could be a new model for tuberculosis surveillance in countries without molecular/genomic epidemiology programs.Systematic molecular/genomic epidemiology studies for tuberculosis surveillance cannot be implemented in many countries. We selected Panama as a model for an alternative strategy. Mycobacterial interspersed repetitive unit–variable-number tandem-repeat (MIRU-VNTR) analysis revealed a high proportion (50%) of Mycobacterium tuberculosis isolates included in 6 clusters (A–F) in 2 provinces (Panama and Colon). Cluster A corresponded to the Beijing sublineage. Whole-genome sequencing (WGS) differentiated clusters due to active recent transmission, with low single-nucleotide polymorphism–based diversity (cluster C), from clusters involving long-term prevalent strains with higher diversity (clusters A, B). Prospective application in Panama of 3 tailored strain–specific PCRs targeting marker single-nucleotide polymorphisms identified from WGS data revealed that 31.4% of incident cases involved strains A–C and that the Beijing strain was highly represented and restricted mainly to Colon. Rational integration of MIRU-VNTR, WGS, and tailored strain–specific PCRs could be a new model for tuberculosis surveillance in countries without molecular/genomic epidemiology programs

Avaliação da eficácia da esterilização do instrumental odontológico na clínica de odontologia de Unibe

Introduction: In the field of dentistry, one way to prevent cross-contamination between patients is by eliminating blood waste and other fluids that have been obtained during the use of instruments. The objective of this research was to evaluate the effectiveness of autoclaving dental instruments in the areas of Endodontics and Periodontics. Methods: An in-vitro, experimental and cross-sectional study was performed on a population of 75 students in comprehensive clinics iii, iv and v at the Unibe dental clinic. 60 samples were taken using smears, which were then inoculation on chromo-agar orientation petri plates and subsequently incubated. The sample consisted of: 10 endodontic files in closed boxes before sterilization in the autoclave, the same 10 endodontic files after sterilization in the autoclave, 10 periodontal instruments (curettes and scalers) before and after sterilization in the autoclave with cloths in perforated boxes, and 10 periodontal instruments before and after sterilization in the autoclave with pouches in perforated boxes.  Conclusion: 60% of the endodontic files after sterilization were found not to be contaminated and 69% for both cloths and pouches had no contamination.Introducción: en el área de la odontología, una de las maneras para prevenir que se produzca una contaminación cruzada entre pacientes es eliminando los residuos de sangre y otros fluidos que han sido obtenidos durante la utilización de los instrumentos. El objetivo de esta investigación es evaluar la eficacia de la esterilización en la autoclave del instrumental odontológico del Área de Endodoncia y Periodoncia. Métodos: se realizó un estudio in vitro, experimental y transversal en una población de 75 estudiantes que se encuentran en la clínica integral III, IV y V de la clínica dental de Unibe. Se tomaron 60 muestras, a las cuales se les realizó un frotis; estas fueron inoculadas en placas petris cromo-agar orientación y posteriormente incubadas. La muestra estuvo constituida por 10 limas endodónticas en cajas cerradas antes de esterilizar en la autoclave, 10 limas endodónticas después de esterilizar en la autoclave, 10 instrumentos periodontales (curetas y jaquetes) antes de esterilizar en paños en la autoclave en cajas perforadas, 10 de los mismos instrumentos después de esterilizar en paños en la autoclave, 10 instrumentos periodontales antes de esterilizar en fundas en la autoclave en cajas perforadas y estas mismas 10 después de haber sido esterilizadas en fundas en la autoclave. Conclusión: se determinó que el 60% de las limas, después de esterilizar, no estaba contaminado y que el 69%, para ambos paños y fundas, no presentaba contaminación.  Introdução: na área da odontologia, uma das maneiras para prevenir que se produza uma contaminação cruzada entre pacientes é quando se eliminam os resíduos de sangue e outros fluídos que foram obtidos durante a utilização dos instrumentos. O objetivo desta pesquisa é avaliar a eficácia da esterilização na autoclave do instrumental odon-tológico da Área de Endodontia e Periodontia. Métodos: realizou-se um estudo in vitro, experimental e transversal na população de 75 estudantes que se encontram na clínica integral iii, iv e v da clínica dental de Uni-be. Tomaram-se 60 amostras, nas quais foi realizado um esfregaço; estas foram inoculadas em placas de Petri cromo-agar orientação e, posterior-mente, incubadas. A amostra esteve constituída por 10 limas endodôn-ticas em caixas fechadas antes de esterilizar na autoclave, 10 limas endo-dônticas depois de esterilizar na autoclave, 10 instrumentos periodontais (curetas e jaquetas) antes de esterilizar em panos na autoclave em caixas perfuradas, 10 dos mesmos instrumentos depois de esterilizar em panos autoclave, 10 instrumentos periodontais antes de esterilizar em bolsas de autoclave em caixas perfuradas e estas mesmas 10 depois de terem sido esterilizadas em bolsas na autoclave. Conclusão: determinou-se que 60% das limas, depois de esterilizar, não estavam contaminadas e que 69%, para ambos os panos e bolsas, não apresentavam contaminação