Advances in automatic detection technology for images of thin blood film of malaria parasite / 中国血吸虫病防治杂志

This paper reviews the computer vision and image analysis studies aiming at automated diagnosis or screening of malaria in microscope images of thin blood film smears. On the basis of introducing the background and significance of automatic detection technology,the existing detection technologies are summarized and divided into several steps,including image acqui-sition,pre-processing,morphological analysis,segmentation,count,and pattern classification components. Then,the princi-ples and implementation methods of each step are given in detail. In addition,the promotion and application in automatic detec-tion technology of thick blood film smears are put forwarded as questions worthy of study,and a perspective of the future work for realization of automated microscopy diagnosis of malaria is provided.

Infecção natural de pombos (Columba livia) por Cryptosporidium spp / Natural infection of pigeons (Columba livia) with Cryptosporidium spp

O estudo teve como objetivo diagnosticar microscopicamente e molecularmente a presença de oocistos de Cryptosporidium spp. provenientes de amostras fecais de pombos (Columba livia) no município do Rio de Janeiro. As amostras fecais foram coletadas frescas, logo após as aves defecarem e acondicionadas sob refrigeração e encaminhadas para o processamento e pesquisa de oocistos de Cryptosporidium spp. ao laboratório de Protozoologia do Departamento de Parasitologia, da Universidade Federal Rural do Rio de Janeiro. As amostras foram submetidas a técnica de centrifugação e flutuação com solução saturada de açúcar e as lâminas observadas com objetiva de 40X. Nas amostras positivas para a presença de oocistos de Cryptosporidium spp. foi realizada a extração de ácido desoxirribonucleico (DNA) para uso nas reações em cadeia pela polimerase (PCR) e Nested-PCR. Um total de 387 amostras fecais de pombos foram obtidas, no diagnóstico microscópico foi possível a observação de oocistos deste parasita em 81 amostras (20,93%). Destas, 53 amostras amplificaram DNA específico para Cryptosporidium spp. na reação da Nested-PCR. Mundialmente, Cryptosporidium spp. parasitando pombos é assinalado em apenas quatro países: Turquia, China, Irã e Tailândia. O resultado encontrado neste trabalho, em três bairros populosos do município do Rio de Janeiro, revelou ser preocupante, por serem áreas onde há uma quantidade acentuada da população animal e humana, facilitando a dispersão e contaminação ambiental dos oocistos. Este é o primeiro registro no Brasil de parasitismo de Cryptosporidium spp. tendo como hospedeiro o pombo e estes resultados, não devem ser negligenciados.

The aim of this study was to diagnose microscopically and molecularly the presence of Cryptosporidium spp. oocysts from pigeons (Columba livia) faecal samples in Rio de Janeiro city. The fecal samples were collected fresh, after the birds defecated and conditioned under refrigeration and sent to the processing and research of Cryptosporidium spp. oocysts to the protozoology laboratory of the Parasitology Department, Universidade Federal Rural do Rio de Janeiro. The samples were submitted to centrifugation and flotation with saturated sugar solution technique and the slides observed with a 40X objective. In the positive samples for the Cryptosporidium spp. oocysts the extraction of deoxyribonucleic acid (DNA) for polymerase chain reaction (PCR) and NestedPCR was performed. A total of 387 pigeons faecal samples were obtained, in the microscopic diagnosis it was possible to observe oocysts of this parasite in 81 samples (20.93%). Of these, 53 samples amplified DNA specific for Cryptosporidium spp. in the Nested-PCR reaction. Worldwide, Cryptosporidium spp. parasitizing pigeons is reported in only four countries: Turkey, China, Iran and Thailand. The results found in this study, in three populated neighborhoods of Rio de Janeiro city, were worrisome because they are areas where there is a marked quantity of animal and human population, facilitating the dispersion and environmental contamination of oocysts. This is the first record in Brazil of parasitism of Cryptosporidium spp. having as host the pigeon and these results, should not be neglected.

Importancia del estudio histopatológico en la determinación de las causas de defunción de autopsias médico legales cuya manera de muerte se clasificó como natural / Importance of histopathology in determining the causes of death of medicolegal autopsies whose manner of death was classified as a natural

En este artículo se discute la necesidad de realizar estudios histopatológicos para dilucidar el diagnóstico final en las autopsias médico legales de los casos que hayan sido catalogados como muerte natural. La histología es una herramienta que ayuda a confirmar o refutar los hallazgos macroscópicos, por tanto se ha demostrado su utilidad en los casos en los cuales no se tiene un mecanismo de muerte claro. Se estudiaron todos los protocolos de autopsia durante el año 2011 clasificados como muerte natural y se les realizó estudios histopatológicos para confirmar o descartar el diagnóstico previamente anotado como responsable de la muerte, obteniéndose que solo el 42,62% coincide completamente tanto macroscópicamente como microscópicamente. Por lo que sigue siendo la recomendación, realizar a todas las muertes naturales los análisis histopatológicos, mientras los recursos humanos y materiales así lo permitan.

In this paper it is discussed the need to realice histopathologics studies to explain the final diagnosis in the autopsies of the cases that have been catalogued as natural death. The histology is a tool that helps to confirm or refute the macrocospic findings therefore his usefulness has been demonstrated in the cases in which the mechanism of death is not clear. All the protocols of autopsy during the year 2011 classified as natural death were studied to confirm or to reject the diagnosis before annotated like responsible for the death, being obtained that only the 42,62 % coincides completely, macrocospic and microscopically. For what it continues being the recommendation, to do the histopathologyc studies to all of the natural deaths, while the human and material resources allow it.

Evaluación de la calidad del diagnóstico de la malaria por microscopía óptica en laboratorios provinciales de la República de Angola / Evaluation of the quality of malaria diagnosis by optical microscopy in provincial laboratories of the Republic of Angola

INTRODUCCIÓN: la malaria continúa siendo uno de los más importantes problemas de la salud pública a nivel mundial y afecta severamente al continente africano. OBJETIVO: evaluar el nivel de conocimientos teóricos y prácticos en el diagnóstico de la malaria de un grupo de técnicos dedicados a esta actividad. MÉTODOS: entre los años 2010 y 2012, se realizó un estudio cuasi experimental de evaluación en la red de salud, en 14 laboratorios provinciales de las 18 provincias de la República Angola, donde se entrenaron 243 técnicos que realizan habitualmente el diagnóstico de la malaria. Se hicieron entrenamientos de 10 días (70 horas) cumplimentando un programa que incluyó clases prácticas y teóricas, y sus respectivas evaluaciones inicial y final. RESULTADOS: después de los entrenamientos en cada una de las 14 provincias evaluadas la frecuencia de los técnicos desaprobados en la evaluaciones teóricas y prácticas disminuyó significativamente, (p<0,01). CONCLUSIONES: este es el primer trabajo realizado en Angola donde se demuestra una mejoría cualitativa y cuantitativa tanto en los conocimientos teóricos y habilidades prácticas de los técnicos después de un entrenamiento y readiestramiento, y constituye el primer paso de un esfuerzo encaminado para mejorar el diagnóstico de la malaria en el país(AU)

INTRODUCTION: malaria continues to be one of the main public health problems worldwide, severely affecting the African continent. OBJECTIVE: evaluate the level of theoretical and practical competence in the diagnosis of malaria achieved by a group of technicians engaged in this activity. METHODS: an evaluative quasi-experimental study was conducted from 2010 to 2012 in 14 provincial laboratories from the 18 provinces of the Republic of Angola, where 243 technicians received training in the field of malaria diagnosis. Training extended for 10 days (70 hours) based on a syllabus which included theoretical and practical lessons as well as an initial and a final evaluation. RESULTS: a post-training evaluation conducted in 14 provinces showed a significant decrease in the number of technicians failing their theoretical and practical tests (p<0.01). CONCLUSIONS: this is the first evaluation carried out in Angola in which qualitative and quantitative improvement is observed both in the theoretical knowledge and the practical skills of technicians after receiving training or retraining. It is also a first step in an effort to improve the quality of malaria diagnosis in the country(AU)