Evolución del uso de nanopartículas en diagnóstico y tratamiento del cáncer

The use of nanoparticles in the health area is a research topic that has been increasing in recent years, from that perspective this work focused on making a characterization of nanoparticles, their evolution and interaction with blood, aspect addressed through the description of the biomagnetic fluid, focusing on characteristics such as viscosity and geometry. Also, the evolution of the applications or techniques in which nanoparticles have been used is presented, focusing the review on cancer treatments, for which the four progressive generations of this research field were considered, as well as the use of nanoparticles in diagnostic imaging. Finally, some fields of implementation and study in Colombia were identified. The review carried out allows concluding that the evolution of the use of nanoparticles in medical applications has made possible the realization of targeted cancer treatments; in this sense, the incidence of SPIONs in the advances achieved recently is recognized, as well as the importance of deepening the study of the movement of these particles.El uso de nanopartículas en el área de la salud es un tema de investigación que ha venido incrementándose en los últimos años, desde esa perspectiva este trabajo se centró en hacer una caracterización de las nanopartículas, su evolución e interacción con la sangre, aspecto abordado a través de la descripción del fluido biomagnético, centrándonos en características como viscosidad y la geometría. También, se da a conocer la evolución de las aplicaciones o técnicas en las cuales se han venido empleando las nanopartículas, enfocando la revisión realizada en tratamientos contra el cáncer, para lo cual se consideraron las cuatro generaciones progresivas de este campo investigativo, así como el uso de las nanopartículas en imágenes diagnósticas. Finalmente se identificaron algunos campos de implementación y estudio en Colombia. La revisión realizada permite concluir que la evolución del empleo de las nanopartículas en aplicaciones médicas ha posibilitado la realización de tratamientos de cáncer focalizados; en ese sentido se reconoce la incidencia de los SPIONs en los avances logrados recientemente, así como la importancia de profundizar en el estudio del movimiento de estas partículas

Avances en electrodos y biosensores elaborados con nanotubos de carbono

Continuous improvement in manufacturing processes of electrodes and biosensors, facilitates the generation of new implementations in various fields of science and engineering where required applied. An extensive search of scientific articles unpublished research results, databases and journals reveal new trends in the inclusion of Carbon Nanotubes (cnt) as a base material of new electrodes and biosensors highly sensitive and less susceptible to noise. Compression of new construction methodologies including cnt and final operation constitute an opportunity for the generation of new applications and the improvement of actual construction techniques.El mejoramiento continuo en los procesos de fabricación de electrodos y biosensores facilita la generación de nuevas implementaciones en diversos sectores de la ciencia, tales como la física, la química y la biología, así como de la ingeniería, la electrónica, la biomédica y la bioingeniería, en las que se requiere aplicar. Una amplia búsqueda en artículos científicos, bases de datos y revistas especializadas revela las nuevas tendencias en la inclusión de nanotubos de carbono (cnt) como material base de nuevos electrodos y biosensores altamente sensibles y menos susceptibles al ruido. La compresión de las nuevas metodologías de construcción que incluyen cnt y su funcionamiento final constituyen una oportunidad para la generación de aplicaciones y el mejoramiento de las técnicas de construcción actuales

Classification of squamous cell cervical cytology

Cervical cancer occurs significantly in women in developing countries every day and produces a high number of casualties, with a large economic and social cost. The World Health Organization, in the right against cervical cancer, promotes early detection screening programs by difeerent detection techniques such as conventional cytology (Pap), cytology liquid medium (CML), DNA test Human Papillomavirus (HPV), staining with dilute acetic acid and Lugol's iodine solution. Conventional cytology is the most used technique, being widely accepted, inexpensive, and with quality control mechanisms. The test has shown a sensitivity of 38% to 84% and a specificity of 90% in multiple studies and has been considered as the choice test for screening [14]. The cervical cancer is not a public health problems in developed countries since more than three decades, among others because of implementation of other tests such as the CML which has increased the sensitivity to a figures that vary between 76% and 99 %. This test in particular produces a thin monolayer of cells that are examined. In our countries this technique is really far from being applied because of its high cost. In consequence, the conventional cytology has remained in practice as the only possible examination of the cervix pathology. In this technique, a sample of cells from the transformation zone of the cervix is taken, using a brush or wooden spatula, spread onto a slide and fixed with a preservative solution. This sample is then sent to a laboratory for staining and microscopic examination to determine whether cells are normal or not. This task requires time and expertise for the diagnosis. Attempting to alleviate the work burden from the number of examinations in clinical routine scenario, some researchers have proposed the development of computational tools to detect and classify the cells of the transformation cervix zone. In the present work the transformation zone is firstly characterized using color and texture descriptors defined in the MPEG-7 standard, and the tissue descriptors are used as the input to a bank of binary classifiers, obtaining a precision of 90% and a sensitivity of 83 %. Unlike traditional approaches that extract cell features from previously segmented cells, the present strategy is completely independent of the particular shape. Yet most works in the domain report higher precision rates, the images used in these works for training and evaluation are really different from what is obtained in the cytology laboratories in Colombia. Overall, most of these methods are applied to monolayer techniques and therefore the recognition rates are better from what we found in the present investigation. However, the main aim of the present work was thus to develop a strategy applicable to our real conditions as a pre-screening method, case in which the method should be robust to many random factors that contaminate the image capture. A segmentation strategy is very easily misleaded by all these factor so that our method should use characteristics independently of the segmentation quality, while the reading time is minimized, as well as the intra-observer variability, facilitating thereby real application of such screening tools.Maestrí

Estudo fotofísico de novas hexahidroquinolinas como potenciais sensores para biomoléculas em solução

Hexahidroquinolinas são heterociclos nitrogenados reconhecidos pela sua ampla aplicação biológica. Este trabalho apresenta a caracterização fotofísica de novas hexahidroquinolinas, obtidas através do método de síntese multicomponente de Hantzsch, sob catalise pela exposição à radiação de micro-ondas, a fim de melhor entender suas propriedades eletrônicas para fins de aplicação como sensores ópticos. Os compostos foram obtidos com bons rendimentos e possibilitando a preparação de 10 novos derivados de hexahidroquinolina. Esta etapa foi realizada em colaboração com o Departamento de Química Farmacêutica da Universidade de Hacettepe, Turquia. Os estudos para caracterização fotofísica em solução em solventes com diferentes constantes dielétricas utilizando espectroscopia de absorção na região do UV-Vis e de emissão de fluorescência. Os estudos fotofísicos indicaram que os compostos absorvem na região do UV sem apresentar efeito solvatocrômico significativo. Baseado na relação de Strickler-Berg conclui-se que as transições eletrônicas são permitidas por spin e por simetria, relacionadas a transições do tipo π→π*. As bandas de emissão localizam-se em torno de 400-500 nm com um efeito solvatocrômico considerável. A analise estrutural mostra que não há grandes mudanças entre os estados fundamental e excitado. Também foram realizados estudos teóricos em colaboração com o Grupo de Química Teórica do IQ/UFRGS para melhor compreender as propriedades eletrônicas destes compostos obtidas experimentalmente. Por fim, com base nas suas propriedades fotofísicas, estudos preliminares dos compostos como sensores para o estudo de interação com albumina sérica bovina (BSA) foram realizados, indicando forte interação com esta biomacromolécula.Hexahydroquinolines are nitrogen heterocycles recognized for their wide biological application. This work presents the photophysical characterization of these compounds, obtained through the Hantzsch multicomponent synthesis method, under catalysis by exposure to microwave radiation, in order to better understand their electronic properties for application purposes as optical sensors. The compounds were obtained in good yields and enabling the preparation of 10 new hexahydroquinoline derivatives. This step was carried out in collaboration with the Department of Pharmaceutical Chemistry at the University of Hacettepe, Turkey. Studies for photophysical characterization in solution in solvents with different dielectric constants using absorption spectroscopy in the UV-Vis and fluorescence emission regions. Photophysical studies indicated that the compounds exhibit absorption in the UV region without showing any significant solvatochromism. Based on the Strickler-Berg relation it is concluded that the transitions are of the π→π* type. The emission bands are located around 400-500 nm and a considerable solvatochromic effect. It is also observed that there was no change in the emission band profile. Structural analysis shows that there are no major changes between ground and excited states. Theoretical studies were also carried out in collaboration with the Theoretical Chemistry Group (IQ/UFRGS) to better understand the electronic properties of these compounds obtained experimentally. Finally, based on their photophysical properties, preliminary studies were carried out with the compounds as optical sensors for the study of interaction with bovine serum albumin (BSA), indicating a strong interaction with this biomacromolecule

Políticas afirmativas e construção da identidade em universitários afrobrasileiros

En la última década las políticas de acción afirmativa han proporcionado transformaciones significativas en la sociedad brasileña fomentando el debate y la consolidación de la democratización en el acceso a la Educación Superior. Este estudio analiza las implicaciones de las políticas de acción afirmativa en la construcción de la identidad de los estudiantes afro-brasileños. Analizando el testimonio de veintidós estudiantes de la Universidad Federal de Paraná, que ingresaron en la universidad a través del sistema de cuotas raciales y participaron en el Proyecto Afroatitude, observándose un cambio significativo en la configuración de la identidad racial. Por lo tanto, si antes de su participación en el mencionado proyecto sus discursos mostraban una concepción naturalista de la constitución de la identidad racial y ocultaba las actitudes sociales sesgadas, después fue posible observar una redefinición de las dimensiones de la identidad racial, identidad académica, cuota identidad titular y la identidad del grupo. Esta redefinición de la identidad dio lugar a una mayor integración en el aparato institucional y en la cultura universitaria, a la apropiación de los conocimientos y lugares sociales, a la comprensión de los múltiples factores determinantes en el proceso de constitución social de la identidad y de la autonomía de los individuos, a la experiencia de la formación política capaz de movilizar a las fuerzas de cambio, a la sustitución de la inercia de la identidad mediante la participación activa del sujeto como un ser histórico en la construcción de la sociedad .In the last decade, affirmative action policies have provided significant transformations in Brazilian society by fostering debate and consolidating the democratization of access to higher education. This study analyzes the implications of affirmative action policies in the construction of the identity of Afro-Brazilian students. Analyzing the testimony of twenty-two students at the Federal University of Parana, which entered the university through the system of racial quotas and participated in the Project Afroatitude, we observed a significant change in the configuration of racial identity. Thus, if prior to their participation in the project mentioned his speeches showed a naturalisticconception of the racial constitution of identity and hiding biased social attitudes, after it was possible to observe a redefinition of the dimensions of racial identity, academic identity, quota holder identity and group identity. This redefinition of identity led to greater integration into the institutional apparatus and the university culture, appropriation of knowledge and social places, understanding of the multiple determinants in the process of social constitution of identity and empowerment of individuals, experience of political formation capable of mobilizing forces of change, replacing the inertia of stagnation identity through active participation of the subject as a historical being in the building society.Na última década as políticas de ações afirmativas vêm proporcionando transformações significativas na sociedade brasileira ao promoverem o debate e consolidando a democratização de acesso ao ensino superior. O presente estudo de caso analisa implicações das políticas de ação afirmativa na construção da identidade de universitários afrobrasileiros. Analisando os depoimentos de vinte e dois estudantes da Universidade Federal do Paraná que ingressaram pelo sistema de cotas raciais e participaram do Projeto Afroatitude, observou-se uma mudança significativa na configuração da identidade racial. Assim, se anteriormente à sua participação no mencionado Projeto seus discursos evidenciaram uma concepção naturalizante sobre a questão racial da constituição da identidade e do ocultamento de atitudes sociais preconceituosas, após a mesma pôde-se observar uma ressignificação das dimensões da identidade racial, da identidade universitária, da identidade de cotista e da identidade de grupo. Essa ressignificação identitária propiciou maior integração ao aparelho institucional universitário e à cultura, apropriação de saberes e de lugares sociais, compreensão das múltiplas determinações sociais no processo de constituição da identidade e de emancipação dos indivíduos, experiência de formação política capaz de mobilizar forças de transformação, substituindo a inércia de uma estagnação identitária pela participação ativa do sujeito enquanto ser histórico na construção da sociedade

Simulación de la presión plantar en adultos mayores

To understand the behavior of the plantar pressure in elderly people, and the factors that influence on it, this is of interest to several researchers, due to the accelerated aging of the population and the consequences that this phenomenon carries. In this work, a simulation in 3D of the human foot has been done during the march, using the finite elements method. This study used the data of several elders, the national average of elders and a young individual as control. The peak pressure and the contact area were obtained, finding the existence of intrinsic parameters which modified the footprint of an elder, such as the weight and height; the greater weight, the greater peak pressure, and the greater height, the lower contact region. Men, unlike women, present the major contact area during the march. This study found values of average peak pressure in elders, 7,325 ± 3,97 psi in the heel support stage, 14,25 ± 1,60 psi in the charge transference stage and 16 ± 7,77 psi in the takeoff stage of the heel.Comprender el comportamiento de la presión plantar en adultos mayores y los factores que influyan sobre la misma es de interés considerando el acelerado envejecimiento de la población. En este trabajo se realizó una simulación 3D del pie humano durante la marcha utilizando el método de los elementos finitos, para el estudio se utilizaron los datos de varios adultos mayores, el promedio nacional de adultos mayores y un individuo joven como control. Se obtuvo la presión pico y el área de contacto, encontrando que existen parámetros intrínsecos que modifican la huella plantar en un adulto mayor, como el peso y la estatura, a mayor peso mayor presión pico, y a mayor estatura menor región de contacto. Los hombres presentan mayor área de contacto durante la marcha que las mujeres. Este estudio encontró valores de presión pico promedio en los adultos mayores, 7,325 ± 3,97 psi en la fase de apoyo de talón, 14,25 ± 1,60 psi en la fase de transferencia de carga y 16 ± 7,77 psi en la fase de despegue de talón

Social practice communities and debate about psychology education

Este artículo presenta algunas reflexiones sobre la aplicación del concepto de comunidad de práctica social, específicamente a los estudiantes de psicología en un proceso de reflexión acerca de su educación universitaria. Participaron los estudiantes de cuarto y quinto año de Psicología de la Universidad Federal de Paraná (UFPR) y Universidad Tuiuti de Paraná (UTP). El objetivo principal de esta actividad fue aproximar estudiantes de diferentes instituciones de Educación Superior, una pública y una privada, para que juntos reflexionasen acerca de su formación profesional. Como consecuencia de la perspectiva teórica adoptada por la Psicología histórico-cultural, se da por supuesto que cuando los sujetos de diferentes culturas (por lo tanto incorporado en comunidades con prácticas sociales específicas) desarrollan actividades comunes con oportunidades de compartir significados, estos establecerán relaciones personales, y compartirán las vivencias de su mundo. Las diferencias que aparecen en esa relación son claves para impulsar un aprendizaje participativo, significativo, emotivo-expresivo y reflexivo para el desarrollo de sujetos envueltos en esa experiencia. Respecto a la metodología tenemos como principio que el proceso de grupo de intercambio de experiencias, recuerdos y reflexiones sobre años anteriores, y las reflexiones compartidas sobre la formación profesional de psicólogos rseulta tan importante respecto a los resultados de las actividades que deberían ser planeadas por los propios estudiantes. El análisis interpretativo de los resultados indica una orientación predominante hacia la formación en práctica clínica, en el caso de la UTP, y hacia la investigación en la UFPR. Una formación más generalista y basada fuertemente en presupuestos epistemológicos y teóricos en la UFPR. Respecto a la UTP la formación está más enfocada al mercado de trabajo para la aplicación práctica de la psicología clínica. Los propios estudiantes de las dos universidades concluyeron que no se sentían seguros y suficientemente preparados para enfrentarse al ejercicio autónomo como psicólogos profesionales. Consideramos que la participación en este proyecto de investigación ha permitido una reflexión crítica sobre la formación de psicólogos, afectando al desarrollo de su identidad profesional.This article presents reflections upon application of the concept of a social practice community, specifically involving psychology students in a reflective process about their university educations. Students from the fourth and fifth years of the psychology programs at the Federal University of Parana (UFPR) and Tuiuti University of Parana (UTP) participated. The primary objective of this activity was to unite students from two different higher education institutions, one public and one private, so that they could combine their thoughts about their professional educations. Stemming from the theoretical perspective of historical-cultural psychology, the assumption was that when subjects from different cultures (hence embedded into communities with specific social practices) develop common activities with opportunities for sharing meanings, establishing personal relationships, and sharing life experiences, differences would spur involved subjects into further reflection, self-awareness, learning, and development. The principle behind the methodology consisted of our belief that the group process where subjects shared their experiences, memories, and reflections about previous years in the respective programs and their education as psychologists is as important as the final result of these activities. Interpretive analysis of the results indicates an overall orientation towards clinical practice and training at UTP and towards research at UFPR. The education at UFPR is more general and strongly based upon epistemological and theoretical assumptions, while that at UTP is aimed more at the job market and practical application of clinical psychology. The students from the two universities themselves concluded that they didn’t feel confident and sufficiently prepared enough to act autonomously as professional psychologists. We consider that participation in this research project enabled students to have a more critical reflection about psychology education, affecting development of their professional identities.Este artigo apresenta reflexões sobre a aplicação do conceito de comunidade de prática social junto a estudantes de Psicologia em um processo de reflexão sobre a formação universitária. Participaram estudantes do quarto e quinto ano dos cursos de Psicologia da Universidade Federal do Paraná e da Universidade Tuiuti do Paraná. Esta atividade teve como objetivo principal aproximar alunos de duas diferentes instituições de ensino (uma pública e outra particular) para que em conjunto refletissem sobre sua formação profissional. Decorrente da perspectiva teórica adotada da Psicologia histórico-cultural o pressuposto foi o de que quando sujeitos de culturas diferentes, portanto, inseridos em comunidades de práticas sociais singulares, desenvolvem atividades comuns com oportunidade de partilharem significados, estabelecerem relações pessoais, compartilharem suas vivências no mundo. As diferenças que aparecem nessa relação são mobilizadoras para uma aprendizagem participativa, significativa, emotiva-expressiva e reflexiva e para o desenvolvimento dos sujeitos envolvidos nessa experiência. Em relação à metodologia tínhamos como princípio que o processo do grupo de trocar experiências, recordações sobre os anos anteriores do curso e as reflexões partilhadas sobre a formação profissional de psicólogos era tão importante quanto o resultado das atividades as quais deveriam ser planejadas pelos próprios estudantes. A análise interpretativa dos resultados indicou orientação predominante para a formação e prática clínica no caso da UTP e para a pesquisa na UFPR; uma formação mais generalista e fortemente embasada em pressupostos epistemológicos e teóricos na UFPR, enquanto na UTP uma formação mais voltada para o mercado de trabalho e para a aplicação prática da Psicologia clínica. Os próprios estudantes das duas universidades concluíram não se sentirem seguros e com formação suficiente para enfrentarem o exercício autônomo da profissão de psicólogos. Consideraram que a participação nesse projeto possibilitou uma reflexão crítica sobre a formação do psicólogo, com efeitos na constituição de suas identidades profissionais.peerReviewe

Color descriptors for cytology smear images analysis

The technique Pap conventional cytology is used as a means of screening to identify normal and abnormal cells, which can prevent cervical cancer. However, a high level of expertise by the cytopathologist performing screening is required, and considering the number of samples to be examined in a working day, increasing the possibility of error. Therefore, several strategies have been implemented to automate this process by taking the original image and converting to grayscale, but this way the information related to the color is lost, a feature that provides a high discriminative power of the elements of interest (nucleus and cytoplasm). In this work images obtained in a database of public domain cell cervical cytology, a step of preprocessing was applied to correct lighting and eliminate image noise, then color two descriptors were implemented; the Dominant Color Descriptor (DCD) and the Descriptor of the Distribution of Color (DDC) for characterizing the content of the images. As a result of this study the implementation of a preprocessing stage in the cell image analysis of cervical cytology combined with the use of information related to the color achieved effectively make detection nucleus and cytoplasm, able to develop a method automatic detection of abnormal cells and thus prevent cervical cancer