Staining blindly: an update on coloring techniques for fecal smears in parasitology: a scoping review.

Dye application for parasite highlighting in the Ova and Parasite exam is a common practice in parasitology diagnosis. Methods: A scoping review investigated how staining solutions interact with parasite structures. After screening 1334 papers, 35 met eligibility criteria. Results: Differentiating background from foreground in the fecal smear under light microscopy is the core of the research on this topic. Refractivity, unevenness of staining, size and temperature were explored to enhance staining protocols. Cryptosporidium spp. and Microsporidia were the main studied species. Conclusion: Studies on diagnostic efficacy outperform those that elucidate the physical-chemical interaction between dyes and parasites. An alternative approach involves technicians using computational tools to reduce subjectivity in fecal smear interpretation, deviating from conventional methods.

What is this article about? Coloring parasites during fecal exams has been widely used to find parasites in human feces. We searched for articles that could help us to answer the question: 'How do dyes give color to parasites?'. Then, we filtered the information from a total of 1334 articles to 35. What were the results? Cryptosporidium spp. and Microsporidia are microbes that can be seen only through a microscope. Researchers were interested in these two species in the last 40 years. Differentiating parasites from dirt on a glass slide is the main problem researchers are trying to solve. The way the light goes through parasites under a microscope, variation of staining, size and temperature of dyes have been explored to identify what gives better results in coloring protocols. What do the results of the study mean? Little is known about the chemical interaction between dyes and parasites. On the other hand, there are many studies on how good coloring methods are and comparing protocols. An alternative to the conventional approaches in staining parasites is the use of computational tools to reduce doubt in the exam interpretation by technicians.

Toward automating the diagnosis of gastrointestinal parasites in cats and dogs.

Diagnosing gastrointestinal parasites by microscopy slide examination often leads to human interpretation errors, which may occur due to fatigue, lack of training and infrastructure, presence of artifacts (e.g., various types of cells, algae, yeasts), and other reasons. We have investigated the stages in automating the process to cope with the interpretation errors. This work presents advances in two stages focused on gastrointestinal parasites of cats and dogs: a new parasitological processing technique, named TF-Test VetPet, and a microscopy image analysis pipeline based on deep learning methods. TF-Test VetPet improves image quality by reducing cluttering (i.e., eliminating artifacts), which favors automated image analysis. The proposed pipeline can identify three species of parasites in cats and five in dogs, distinguishing them from fecal impurities with an average accuracy of 98,6%. We also make available the two datasets with images of parasites of dogs and cats, which were obtained by processing fecal smears with temporary staining using TF-Test VetPet.

TF-Test techniques for the laboratory diagnosis of gastrointestinal parasites of humans and animals

Intestinal parasites inhabit the intestinal tract of humans and animals, causing damages whose severity depends on several factors related to the parasite and the host. Immunocompromised individuals are more likely to develop severe forms of parasitic infestation. The diagnosis of the gastrointestinal parasitosis is mainly performed by the examination of the feces, which consists of the direct visualization and identification of the parasites eliminated through the feces. These tests are generally low sensitive and the microscope slides contain a large number of impurities, which can impair the result of the diagnosis. In order to improve the diagnostic accuracy, a new parasitological technique called Three Fecal Test (TF­Test) was developed. To further improve its diagnostic accuracy, few modifications of the original protocols have been made with the years. In this study the performance of these new techniques to detect gastrointestinal parasites in human and animal fecal samples was described and discussed in relation to the performance of other conventional coprological tests. It could be concluded that the TF­Test conventional and modified can be used for the diagnosis of several human and animal parasites, with satisfactory results.

Detection of intestinal parasites in human faecal samples using dissolved air flotation.

OBJECTIVE: Ova and parasite (O&P) examination is recommended for the laboratory diagnosis of agents causing parasitic infections; however, this exam requires scientific and technological improvements to enhance its diagnostic validity. Dissolved air flotation (DAF) is an efficient technical principle separating suspended solids in a liquid medium. We aimed to develop and validate a new procedure for intestinal parasite detection with DAF. METHODS: In this study, we collected samples from 500 volunteers, screened them by direct examination, and transferred the material to tubes using the Three Faecal Test (TF-Test) for triplicate DAF tests. We evaluated physical-chemical parameters and DAF prototype components through quantifying parasites recovered from floated and non-floated regions of the flotation column. The DAF operation protocol was validated with the gold standard results. RESULTS: The 10% saturated volume proportion and cationic surfactant showed regularity and high parasite recovery (80%). Modifications of the needle device did not influence parasite recovery (p > 0.05). Sensitivity, specificity, accuracy and kappa agreement obtained with the DAF protocol were 91%, 100%, 93% and substantial (k = 0.64), respectively. CONCLUSION: The DAF principle could be used to process faecal samples in routine laboratory exams, enabling intestinal parasite detection.

Automated Diagnostics: Advances in the Diagnosis of Intestinal Parasitic Infections in Humans and Animals.

The increasingly close proximity between people and animals is of great concern for public health, given the risk of exposure to infectious diseases transmitted through animals, which are carriers of more than 60 zoonotic agents. These diseases, which are included in the list of Neglected Tropical Diseases, cause losses in countries with tropical and subtropical climates, and in regions with temperate climates. Indeed, they affect more than a billion people around the world, a large proportion of which are infected by one or more parasitic helminths, causing annual losses of billions of dollars. Several studies are being conducted in search for differentiated, more sensitive diagnostics with fewer errors. These studies, which involve the automated examination of intestinal parasites, still face challenges that must be overcome in order to ensure the proper identification of parasites. This includes a protocol that allows for elimination of most of the debris in samples, satisfactory staining of parasite structures, and a robust image database. Our objective here is therefore to offer a critical description of the techniques currently in use for the automated diagnosis of intestinal parasites in fecal samples, as well as advances in these techniques.

Dissolved air flotation as potential new mechanism for intestinal parasite diagnosis in feces.

The parasitological examination of feces is recommended for the laboratory diagnosis of intestinal parasites due to its practicality, low-cost, and moderate diagnostic sensitivity. Dissolved Air Flotation (DAF) is an efficient technical principle used in other areas to separate dispersed solids. This study sought the preliminary evaluation of a proof-of-concept prototype as a tool for detecting species of parasites by adjusting DAF. Two DAF prototype units were developed to evaluate microbubbles' generation amidst fecal suspension and parasites' capture. For this evaluation, samples were screened and processed by the TF-Test technique (Control) and simultaneously by DAF device. The dimensional and attachment characteristics in the formation of the microbubbles were evaluated, and the percentage of parasitic recovery in floated and not-floated regions compared by Student's t-test. The second prototype unit proved to be more efficient in forming microbubbles with diameters between 34 and 170µm. The flotation tests showed a recovery of 73.27%, 58.12%, 37.85%, and 91.89% for Ascaris lumbricoides, Hymenolepis diminuta, Giardia duodenalis, and Strongyloides stercoralis, respectively. This study confirmed the selective interaction between microbubbles and parasite eggs and larvae during the flotation process using the DAF principle for the first time through imaging.

A historical review of the techniques of recovery of parasites for their detection in human stools.

Since the early 20th century, the detection of intestinal parasites has improved with the development of several techniques for parasitic structures recovery and identification, which differ in sensitivity, specificity, practicality, cost, and infrastructure demand. This study aims to review, in chronological order, the stool examination techniques and discuss their advantages, limitations, and perspectives, and to provide professionals and specialists in this field with data that lays a foundation for critical analysis on the use of such procedures. The concentration procedures that constitute the main techniques applied in routine research and in parasitological kits are a) spontaneous sedimentation; b) centrifugation-sedimentation with formalin-ethyl acetate; and c) flotation with zinc sulfate solution. While selecting a technique, one should consider the purpose of its application and the technical-operational, biological, and physicochemical factors inherent in the procedures used in stool processing, which may restrict its use. These intrinsic limitations may have undergone procedural changes driven by scientific and technological development and by development of alternative methods, which now contribute to the improvement of diagnostic accuracy.

A historical review of the techniques of recovery of parasites for their detection in human stools

Abstract Since the early 20th century, the detection of intestinal parasites has improved with the development of several techniques for parasitic structures recovery and identification, which differ in sensitivity, specificity, practicality, cost, and infrastructure demand. This study aims to review, in chronological order, the stool examination techniques and discuss their advantages, limitations, and perspectives, and to provide professionals and specialists in this field with data that lays a foundation for critical analysis on the use of such procedures. The concentration procedures that constitute the main techniques applied in routine research and in parasitological kits are a) spontaneous sedimentation; b) centrifugation-sedimentation with formalin-ethyl acetate; and c) flotation with zinc sulfate solution. While selecting a technique, one should consider the purpose of its application and the technical-operational, biological, and physicochemical factors inherent in the procedures used in stool processing, which may restrict its use. These intrinsic limitations may have undergone procedural changes driven by scientific and technological development and by development of alternative methods, which now contribute to the improvement of diagnostic accuracy.

Use of the aqueous biphasic system as an alternative for concentration of Ascaris lumbricoides eggs, with non-toxic separation of faecal residues and fats.

OBJECTIVES: Human enteroparasites are considered a serious public health problem in underdeveloped countries located in world regions with tropical, subtropical and equatorial climates. These parasites are commonly diagnosed by the Parasitological Examination of Faeces (PEF), performed by conventional techniques and/or commercial kits that result in tests with low-to-moderate sensitivity, due to the use of destructive chemical solvents to parasite structures, and to present excess adipose substance and digestive residues in their microscopic slides. In order to improve the efficacy of these tests/examinations, this study aimed to investigate a new alternative for the PEF, with the use of Aqueous Biphasic System (ABS). METHODS: For this, four ABSs containing poly (ethylene glycol), PEG (PEG-4000 and PEG-6000), dipotassium phosphate and sodium citrate at different concentrations in the biphasic systems were evaluated with faecal samples containing eggs of Ascaris lumbricoides. RESULTS: The ABS consisting of PEG-4000 and dipotassium phosphate, at concentrations of 55% w/w and 20% w/w, respectively, achieved 100% satisfactory results compared to the conventional TF-Test technique in terms of preservation and concentration of A. lumbricoides eggs, with adequate separation of digestive residues, without using a centrifuge or chemical solvents that may cause harm to the parasites. CONCLUSIONS: This study presents ABS as a new low-cost technical principle for the detection of parasite eggs in PEF. The new technique is simple, fast, non-toxic, not harmful to the parasite and does not require a centrifuge.

UTILISATION DU SYSTÈME BIPHASIQUE AQUEUX COMME ALTERNATIVE À LA CONCENTRATION DES ŒUFS D'ASCARIS LUMBRICOIDES, AVEC SÉPARATION NON TOXIQUE DES RÉSIDUS FÉCAUX ET DES GRAISSES: OBJECTIFS: Les entéroparasites humains sont considérés comme un sérieux problème de santé publique dans les pays sous-développés situés dans des régions du monde aux climats tropicaux, subtropicaux et équatoriaux. L'examen parasitologique des matières fécales (EPMF) permet généralement de diagnostiquer ces parasites, à l'aide de techniques classiques et/ou de kits commerciaux, conduisant à des tests de sensibilité faible à modérée, dus à l'utilisation de solvants chimiques destructeurs pour les structures du parasite et résultant en excès de substances adipeuses et de résidus digestifs dans leurs lames microscopiques. Afin d'améliorer l'efficacité de ces tests/examens, cette étude visait à étudier une nouvelle alternative à l'EPMF, avec l'utilisation du Système Biphasique Aqueux (SBA). MÉTHODES: Pour cela, quatre SBA contenant du poly (éthylène glycol), du PEG (PEG-4000 et PEG-6000), du phosphate dipotassique et du citrate de sodium à différentes concentrations ont été évalués avec des échantillons de matières fécales contenant des œufs d'Ascaris lumbricoides. RÉSULTATS: Le SBA constitué de PEG-4000 et de phosphate dipotassique, à des concentrations respectives de 55% poids/poids et 20% poids/poids, a obtenu des résultats satisfaisants à 100% par rapport à la technique conventionnelle du TF-Test, en termes de préservation et de concentration des œufs de A. lumbricoides, avec une séparation adéquate des résidus digestifs, sans utiliser de centrifugeuse ni de solvants chimiques pouvant détruire les parasites. CONCLUSIONS: Cette étude présente le SBA comme un nouveau principe technique peu coûteux pour la détection des œufs de parasites dans l'EPMF. La nouvelle technique est simple, rapide, non toxique, n'endommage pas le parasite et ne nécessite pas de centrifugeuse.

An adaptive probabilistic atlas for anomalous brain segmentation in MR images.

PURPOSE: Automated segmentation of brain structures (objects) in MR three-dimensional (3D) images for quantitative analysis has been a challenge and probabilistic atlases (PAs) are among the most well-succeeded approaches. However, the existing models do not adapt to possible object anomalies due to the presence of a disease or a surgical procedure. Post-processing operation does not solve the problem, for example, tissue classification to detect and remove such anomalies inside the resulting segmentation mask, because segmentation errors on healthy tissues cannot be fixed. Such anomalies very often alter the shape and texture of the brain structures, making them different from the appearance of the model. In this paper, we present an effective and efficient adaptive probabilistic atlas, named AdaPro, to circumvent the problem and evaluate it on a challenging task - the segmentation of the left hemisphere, right hemisphere, and cerebellum, without pons and medulla, in 3D MR-T1 brain images of Epilepsy patients. This task is challenging due to temporal lobe resections, artifacts, and the absence of contrast in some parts between the structures of interest. METHODS: In AdaPro, we first build one probabilistic atlas per object of interest from a training set with normal 3D images and the corresponding 3D object masks. Second, we incorporate a texture classifier based on convex optimization which dynamically indicates the regions of the target 3D image where the PAs (shape constraints) should be further adapted. This strategy is mathematically more elegant and avoids problems with post-processing. Third, we add a new object-based delineation algorithm based on combinatorial optimization and diffusion filtering. AdaPro can then be used to locate and delineate the objects in the coordinate space of the atlas or of the test image. We also compare AdaPro with three other state-of-the-art methods: an statistical shape model based on synergistic object search and delineation, and two methods based on multi-atlas label fusion (MALF). RESULTS: We evaluate the methods quantitatively on 3D MR-T1 brain images of 2T and 3T from epilepsy patients, before and after temporal lobe resections, and on the template and native coordinate spaces. The results show that AdaPro is considerably faster and consistently more accurate than the baselines with statistical significance in both coordinate spaces. CONCLUSION: AdaPro can be used as a fast and effective step for brain tissue segmentation and it can also be easily extended to segment subcortical brain structures. By choice of its components, probabilistic atlas, texture classifier, and delineation algorithm, it can also be extended to other organs and imaging modalities.

TF-Test Quantified: a new technique for diagnosis of Schistosoma mansoni eggs.

OBJECTIVES: Laboratory diagnosis of Schistosoma mansoni eggs is routinely performed by conventional quantitative techniques through the parasitological examination of human faeces. However, the diagnostic sensitivity of this type of exam varies from low to moderate. We aimed to develop a new parasitological technique called TF-Test Quantified (TFT-Quant), for the quantitative detection of S. mansoni eggs in human faeces. METHODS: Four study stages were performed using 43 mice infected by S. mansoni cercariae. These experiments allowed the definition of an operational protocol for TFT-Quant and a comparison of this new technique to the conventional Helm-Teste technique. RESULTS: The results show a good diagnostic efficacy of TFT-Quant, which reached 100% in sensitivity and specificity, indicating an 'Almost Perfect' Kappa (k) agreement. CONCLUSIONS: This new technique provided a quantitative gain in the detection of S. mansoni eggs, largely free of faecal debris. The next stage of this study is the field validation of the TFT-Quant technique with the use of human faecal samples from an endemic region for mansonic schistosomiasis in Brazil (Microregion Jequitinhonha, State of Minas Gerais). In parallel to this validation, computational algorithms will be developed to allow the automated quantitative diagnosis of S. mansoni eggs.

OBJECTIFS: Le diagnostic en laboratoire des œufs de Schistosoma mansoni est systématiquement effectué à l'aide de techniques quantitatives conventionnelles faisant appel à l'examen parasitologique de selles humaines. Cependant, la sensibilité diagnostique de ce type d'examen varie de faible à modérée. Nous avons voulu développer une nouvelle technique parasitologique appelée TF-Test Quantified (TFT-Quant), pour la détection quantitative des œufs de S. mansoni dans les selles humaines. MÉTHODES: Quatre étapes de l'étude ont été réalisées sur 43 souris infectées par des cercaires de S. mansoni. Ces expériences ont permis de définir un protocole opérationnel pour TFT-Quant et de comparer cette nouvelle technique à la technique classique Helm-Teste. RÉSULTATS: Les résultats montrent une bonne efficacité diagnostique de TFT-Quant, dont la sensibilité et la spécificité ont atteint 100%, ce qui indique une concordance kappa (k) «presque parfaite¼. CONCLUSIONS: Cette nouvelle technique a permis un gain quantitatif dans la détection des œufs de S. mansoni, largement exempts de débris fécaux. La prochaine étape de cette étude est la validation sur le terrain de la technique TFT-Quant avec l'utilisation d'échantillons de selles humaines provenant d'une région endémique pour la schistosomiase mansonique au Brésil (Microregion Jequitinhonha, dans l'Etat de Minas Gerais). Parallèlement à cette validation, des algorithmes informatiques de calcul seront développés pour permettre le diagnostic quantitatif automatisé des œufs de S. mansoni.

The Residual Center of Mass: An Image Descriptor for the Diagnosis of Alzheimer Disease.

A crucial quest in neuroimaging is the discovery of image features (biomarkers) associated with neurodegenerative disorders. Recent works show that such biomarkers can be obtained by image analysis techniques. However, these techniques cannot be directly compared since they use different databases and validation protocols. In this paper, we present an extensive study of image descriptors for the diagnosis of Alzheimer Disease (AD) and introduce a new one, named Residual Center of Mass (RCM). The RCM descriptor explores image moments and other techniques to enhance brain regions and select discriminative features for the diagnosis of AD. For validation, a Support Vector Machine (SVM) is trained with the selected features to classify images from normal subjects and patients with AD. We show that RCM with SVM achieves the best accuracies on a considerable number of exams by 10-fold cross-validation - 95.1% on 507 FDG-PET scans and 90.3% on 1374 MRI scans.

A study of intestinal parasites in children of an urban region with excellent sanitary condition reveals high occurrence of Blastocystis spp

Intestinal parasites are among the major causative agents of diseases that affect animals and humans, especially children. In view of this, the current study evaluated the occurrence of these parasitic agents in 737 children in an urban region with excellent sanitation condition of the city of Pedreira, São Paulo, Brazil. Fecal samples from the children were processed with the use of a technique of high diagnostic efficiency (TF-Test®). The diagnosis of these samples resulted in the detection of 557 parasitic structures among eleven genera of parasites, and of 46.4% (342/737) infected children. Blastocystis spp. was found in 69.6% (238/342) of the positive samples and the monoparasitism was accompanied by symptoms in 44 children. Furthermore, 67.8% (232/342) of the infected children had close contact with pets, suggesting a possible zoonotic transmission. Lastly, this study allowed to perform health education to the children, aiming the reduction of new intestinal parasitic infections.

Validation of a new technique to detect Cryptosporidium spp. oocysts in bovine feces.

Due to its important zoonotic potential, cryptosporidiosis arouses strong interest in the scientific community, because, it was initially considered a rare and opportunistic disease. The parasitological diagnosis of the causative agent of this disease, the protozoan Cryptosporidium spp., requires the use of specific techniques of concentration and permanent staining, which are laborious and costly, and are difficult to use in routine laboratory tests. In view of the above, we conducted the feasibility, development, evaluation and intralaboratory validation of a new parasitological technique for analysis in optical microscopy of Cryptosporidium spp. oocysts, called TF-Test Coccidia, using fecal samples from calves from the city of Araçatuba, São Paulo. To confirm the aforementioned parasite and prove the diagnostic efficiency of the new technique, we used two established methodologies in the scientific literature: parasite concentration by centrifugal sedimentation and negative staining with malachite green (CSN-Malachite) and Nested-PCR. We observed good effectiveness of the TF-Test Coccidia technique, being statistically equivalent to CSN-Malachite. Thus, we verified the effectiveness of the TF-Test Coccidia parasitological technique for the detection of Cryptosporidium spp. oocysts and observed good concentration and morphology of the parasite, with a low amount of debris in the fecal smear.

HIGH PREVALENCE OF Blastocystis spp. INFECTION IN CHILDREN AND STAFF MEMBERS ATTENDING PUBLIC URBAN SCHOOLS IN SÃO PAULO STATE, BRAZIL.

After a gastroenteritis outbreak of unknown etiology in the municipality of Sebastião da Grama, São Paulo, Brazil, we conducted a parasitological survey to establish the epidemiological profile of enteroparasitosis in children and staff members attending the public urban schools in operation in town. The cross-sectional study evaluated 172 children aged 11 months to 6 years old and 33 staff members aged 19 to 58 years old. Overall, 96 (55.81%) children and 20 (60.61%) staff members were mono-parasitized, while 58 (33.72%) children and 4 (12.12%) workers were poly-parasitized. Protozoa (88.37%; 72.73%) was more prevalent than helminthes (3.48%; 0%) in children and staff members respectively.Blastocystis spp. was the most prevalent parasite in children (86.63%) and staff members (66.67%). The age of 1 year old or less was found to be associated with increased prevalence of giardiasis [OR = 13.04; 95%CI 2.89-58.91; p = 0.00] and public garbage collection was identified as a protective factor against intestinal helminth infections [OR = 0.06; 95%CI 0.00-0.79; p = 0.03]. Although most of the children tested positive for Blastocystis spp. and also presented clinical signs/symptoms (62.2%), this association was not statistically significant [OR = 1.35; 95%CI 0.53-3.44; p = 0.51]. Intestinal parasites still represent a public health concern and this study underscores the importance of further investigations to better understand the pathogenic role of Blastocystis spp.

TF-Test Modified: New Diagnostic Tool for Human Enteroparasitosis.

Intestinal parasitosis is highly prevalent worldwide, being among the main causes of illness and death in humans. Currently, laboratory diagnosis of the intestinal parasites is accomplished through manual technical procedures, mostly developed decades ago, which justifies the development of more sensitive and practical techniques. Therefore, the main objective of this study was to develop, evaluate, and validate a new parasitological technique referred to as TF-Test Modified, in comparison to three conventional parasitological techniques: TF-Test Conventional; Rugai, Mattos & Brisola; and Helm Test/Kato-Katz. For this realization, we collected stool samples from 457 volunteers located in endemic areas of Campinas, São Paulo, Brazil, and statistically compared the techniques. Intestinal protozoa and helminths were detected qualitatively in 42.23% (193/457) of the volunteers by TF-Test Modified technique, against 36.76% (168/457) by TF-Test Conventional, 5.03% (23/457) by Helm Test/Kato-Katz, and 4.16% (19/457) by Rugai, Mattos & Brisola. Furthermore, the new technique presented "almost perfect kappa" agreement in all evaluated parameters with 95% (P < 0.05) of estimation. The current study showed that the TF-Test Modified technique can be comprehensively used in the diagnosis of intestinal protozoa and helminths, and its greater diagnostic sensitivity should help improving the quality of laboratory diagnosis, population surveys, and control of intestinal parasites.

Evolving technologies for growing, imaging and analyzing 3D root system architecture of crop plants.

A plant's ability to maintain or improve its yield under limiting conditions, such as nutrient deficiency or drought, can be strongly influenced by root system architecture (RSA), the three-dimensional distribution of the different root types in the soil. The ability to image, track and quantify these root system attributes in a dynamic fashion is a useful tool in assessing desirable genetic and physiological root traits. Recent advances in imaging technology and phenotyping software have resulted in substantive progress in describing and quantifying RSA. We have designed a hydroponic growth system which retains the three-dimensional RSA of the plant root system, while allowing for aeration, solution replenishment and the imposition of nutrient treatments, as well as high-quality imaging of the root system. The simplicity and flexibility of the system allows for modifications tailored to the RSA of different crop species and improved throughput. This paper details the recent improvements and innovations in our root growth and imaging system which allows for greater image sensitivity (detection of fine roots and other root details), higher efficiency, and a broad array of growing conditions for plants that more closely mimic those found under field conditions.

Comparative study of five techniques for the diagnosis of canine gastrointestinal parasites.

Differences in the efficacy of diagnostic techniques employed in the parasitological examination of feces are a limiting factor of this laboratory procedure in the field of Veterinary Parasitology. To verify advances in this type of examination in dogs, we conducted a study using a new technique (TFGII/Dog). Fifty naturally infected dogs were housed in individual stalls, and their feces were evaluated comparatively using this technique and four other conventional techniques. The TFGII/Dog showed high levels of sensitivity and efficiency, surpassing the diagnostic accuracy of the other techniques with a kappa concordance index of 0.739 (Substantial), as opposed to 0.546 (Moderate), 0.485 (Moderate), 0.467 (Moderate), and 0.325 (Fair) of the Spontaneous-Sedimentation, Centrifugal-Flotation in Saturated Zinc Sulfate Solution, Centrifugal-Flotation in Saturated Sugar Solution, and Spontaneous-Flotation in Saturated Sodium Chloride Solution techniques, respectively. The combination of positive results of all techniques comprises eight genera of parasites, with Ancylostoma spp. predominating among helminths, and Cystoisospora spp. among protozoa. The TFGII/Dog technique showed better diagnostic performance, and can therefore be considered an important tool for optimizing the results of laboratory routines and for the control of canine gastrointestinal parasites.

Comparative study of five techniques for the diagnosis of canine gastrointestinal parasites / Estudo comparativo de cinco técnicas para o diagnóstico de parasitos gastrointestinais caninos

Differences in the efficacy of diagnostic techniques employed in the parasitological examination of feces are a limiting factor of this laboratory procedure in the field of Veterinary Parasitology. To verify advances in this type of examination in dogs, we conducted a study using a new technique (TFGII/Dog). Fifty naturally infected dogs were housed in individual stalls, and their feces were evaluated comparatively using this technique and four other conventional techniques. The TFGII/Dog showed high levels of sensitivity and efficiency, surpassing the diagnostic accuracy of the other techniques with a kappa concordance index of 0.739 (Substantial), as opposed to 0.546 (Moderate), 0.485 (Moderate), 0.467 (Moderate), and 0.325 (Fair) of the Spontaneous-Sedimentation, Centrifugal-Flotation in Saturated Zinc Sulfate Solution, Centrifugal-Flotation in Saturated Sugar Solution, and Spontaneous-Flotation in Saturated Sodium Chloride Solution techniques, respectively. The combination of positive results of all techniques comprises eight genera of parasites, with Ancylostoma spp. predominating among helminths, and Cystoisospora spp. among protozoa. The TFGII/Dog technique showed better diagnostic performance, and can therefore be considered an important tool for optimizing the results of laboratory routines and for the control of canine gastrointestinal parasites.

As diferenças na eficácia de técnicas de diagnóstico empregadas no exame parasitológico das fezes é um factor limitante desse procedimento de laboratório no campo da Medicina Veterinária. Com o objetivo de confirmar avanços desse tipo de examinação em cães, a abordagem desse trabalho foi apresentar um estudo com o uso de uma nova técnica (TFGII/Dog). Cinquenta cães naturalmente infectados foram alojados em baias individuais, e suas fezes foram avaliadas comparativamente, usando-se a nova técnica e outras quatro técnicas convencionais. O TFGII/Dog apresentou altos níveis de sensibilidade e eficiência, superando o diagnóstico de outras técnicas com um índice de concordância kappa de 0,739 (Substancial), em oposição a 0,546 (Moderado), 0,485 (Moderado), 0,467 (Moderado) e 0,325 (Pobre) de Sedimentação-Espontânea, Centrífugo-Flutuação em Solução Saturada de Sulfato de Zinco, Centrífugo-Flutuação em Solução Saturada de Açúcar, e Flutuação-Espontânea em Solução Saturada de Cloreto de Sódio, respectivamente. A combinação de resultados positivos das técnicas mostrou oito gêneros de parasitos, com Ancylostoma spp. predominando entre helmintos, e Cystoisospora spp. entre os protozoários. A técnica de TFGII/Dog apresentou melhor desempenho diagnóstico e, portanto, pode ser considerada uma importante ferramenta para otimizar os resultados de rotinas de laboratório e o controle de parasitos gastrintestinais de cães.

Hybrid approaches for interactive image segmentation using the live markers paradigm.

Interactive image segmentation methods normally rely on cues about the foreground imposed by the user as region constraints (markers/brush strokes) or boundary constraints (anchor points). These paradigms often have complementary strengths and weaknesses, which can be addressed to improve the interactive experience by reducing the user's effort. We propose a novel hybrid paradigm based on a new form of interaction called live markers, where optimum boundary-tracking segments are turned into internal and external markers for region-based delineation to effectively extract the object. We present four techniques within this paradigm: 1) LiveMarkers; 2) RiverCut; 3) LiveCut; and 4) RiverMarkers. The homonym LiveMarkers couples boundary-tracking via live-wire-on-the-fly (LWOF) with optimum seed competition by the image foresting transform (IFT-SC). The IFT-SC can cope with complex object silhouettes, but presents a leaking problem on weaker parts of the boundary that is solved by the effective live markers produced by LWOF. Conversely, in RiverCut, the long boundary segments computed by Riverbed around complex shapes provide markers for Graph Cuts by the Min-Cut/Max-Flow algorithm (GCMF) to complete segmentation on poorly defined sections of the object's border. LiveCut and RiverMarkers further demonstrate that live markers can improve segmentation even when the combined approaches are not complementary (e.g., GCMFs shrinking bias is also dramatically prevented when using it with LWOF). Moreover, since delineation is always region based, our methodology subsumes both paradigms, representing a new way of extending boundary tracking to the 3D image domain, while speeding up the addition of markers close to the object's boundary-a necessary but time consuming task when done manually. We justify our claims through an extensive experimental evaluation on natural and medical images data sets, using recently proposed robot users for boundary-tracking methods.