Perfil epidemiológico das enteroparasitoses em pré-escolares e escolares da rede municipal de ensino de Sinop - MT / Epidemiological profile of endoparasitoses in preschoolers and school children of the school district of Sinop - state of Mato Grosso

ntrodução: As enteroparasitoses são causadas por protozoários e helmintos e representam um importante proble-ma de saúde pública. As crianças em idade pré-escolar e escolar apresentam maior vulnerabilidade à contaminação por enteroparasitas pelo fato de estarem mais expostas a fatores de risco, tais como hábitos precários de higiene e aglomeração em locais fechados, e por não apresentarem o sistema imunológico totalmente desenvolvido. Os para-sitas mais comumente encontrados nessa faixa etária compreendem Giardia lamblia, Ascaris lumbricoides, Trichuris trichiura e ancilostomídeos. Objetivos: Avaliar a prevalência de enteroparasitos em crianças pré-escolares e escola-res e em caixas de areia de instituições públicas de ensino no município de Sinop-MT. Métodos: O estudo realizado foi transversal, quantitativo com delineamento experimental. Foi realizado no período de julho de 2015 a setembro de 2016. Foram avaliadas crianças pré-escolares e escolares de 3 a 12 anos escolhidas por amostragem de conveniência de quatro instituições da rede municipal de ensino localizadas na região central de Sinop ­ MT e sete afastadas do centro da cidade e que atendem novos bairros e a zona rural. As amostras de fezes foram coletadas pelos responsá-veis das crianças que encaminharam para as instituições de ensino e, posteriormente, foram transportadas ao labo-ratório para realização do exame parasitológico. As amostras de areia foram coletadas a partir de caixas das áreas de recreações de todas as instituições de ensino, sendo coletada 100 gramas de areia da raspagem superficial e pro-funda dos quatro quadrantes e do centro, totalizando 10 amostras/caixa. Os métodos parasitológicos utilizados para análises das amostras de fezes e areia foram Hoffmann, migração ativa, centrífugo-flutuação espontânea por Faust e flutuação espontânea por Willis. Resultados: Foram avaliadas 646 amostras de fezes de crianças pré-escolares e escolares de 3 a 12 anos, apresentando 21,05% de positividade para parasitos intestinais. Giardia lamblia apresentou maior prevalência, seguida de Entamoeba coli, Endolimax nana,Ascaris lumbricoides, Enterobius vermicularis, Hy-menolepis nana, ancilostomídeo e Entamoeba hartmanni. As 80 amostras de areia das caixas das áreas de recreação infantil avaliadas, apresentaram 100% de positividade para G. lamblia, seguida de 66,66% para Toxocara sp. nas areias das áreas centrais e 100% nas periféricas, 66,66% para Toxoplasma gondii nas centrais e 80% nas periféricas, 33,33% para A. lumbricoides nas centrais e 60% nas periféricas e 33,33% de Strongyloides stercoralis somente nas areias das áreas centrais. Conclusão: A faixa etária mais acometida foi verificada entre as crianças de 6 a 12 anos e pode estar relacionada aos precários hábitos de higiene e assim, maior risco de contaminação. Pode-se concluir que os resultados estão de acordo com a maioria dos estudos epidemiológicos realizados no Brasil, demonstrando elevada prevalência de enteroparasitoses em crianças em idade escolar (AU)

Introduction: Protozoa and helminths cause enteroparasitoses, which constitute an important public health issue. Preschoolers and school children, who do not have a fully developed immune system, are more vulnerable to con-tamination by intestinal parasites because they are more exposed to risk factors, such as poor hygiene habits and crowding in closed places. The most common parasites affecting this age group include Giardia lamblia, Ascaris lumbricoides, Trichuris trichiura, and hookworms. Objectives: To evaluate the prevalence of intestinal parasites in preschoolers, school children, and sandboxes of government schools in the city of Sinop ­ state of Mato Gros-so (MT). Methods: This cross-sectional, quantitative study with an experimental design was carried out from July 2015 to September 2016 and included preschoolers and school children aged 3 to 12 years, chosen by convenience sampling from government schools in the school district of the city of Sinop ­ MT; four schools were in the central region of Sinop, whereas seven schools, attended by children living in the suburban and rural areas, were far from the city center. Fecal samples were collected by the children's family and sent to the schools, from where they were transported to the laboratory for parasitological examination. Sand samples were collected from sandboxes in the play areas of the schools. More specifically,100 g of sand was collected by scraping one of the four quadrants or the center of the sandbox surface or deeper into the sandbox, totaling 10 samples/box. The parasitological methods spontaneous sedimentation described by Hoffmann, active migration described by Rugai, centrifugal-spontaneous flotation described by Faust, and spontaneous flotation described by Willis were used to analyze the fecal and sand samples. Results: A total of 646 fecal samples obtained from preschoolers and school children aged 3 to 12 years were evaluated; 21.05% of the samples tested positive for intestinal parasites. As for the sand samples, 100% tested positive for intestinal parasites. In all the fecal and sand samples that tested positive for intestinal parasites, G. lamblia predominated, followed by Toxacara sp, Toxoplasma gondii, A. lumbricoides, Enterobius vermicularis, Hymenolepis nana, Strongyloides stercoralis, hookworm, Entamoeba coli, Endolimax nana, and Entamoeba hart-manni, commensal amoebae of the large intestine, were also identified. Conclusion: Children aged 6 to 12 years were the most affected by enteroparasitoses. This may be related to poor hygiene habits, which puts these children at greater risk of contamination. The results agree with most epidemiological studies conducted in Brazil and show a high prevalence of enteroparasitoses in children (AU)

Epidemiology of dermatomycoses in children in Northern Mato Grosso 2015-2020.

OBJECTIVES: Dermatomycoses, fungal diseases that affect the superficial layers of skin, hair or nails, are a public health concern due to their high prevalence. In Brazil, dermatomycoses are not notifiable diseases, so only fragmented epidemiological studies have been reported in the national literature. To evaluate the epidemiological profile of dermatomycoses in preschoolers and school children in Sinop, Mato Grosso (MT), Brazil. METHODS: Classic methods were used to perform 782 mycological examinations to identify dermatophytosis, cutaneous candidosis and pityriasis versicolor in preschoolers and school children aged between 6 months and 12 years in 11 educational institutions in Sinop, MT. RESULTS: Among the evaluated clinical specimens, 5.2% tested positive for dermatophytosis, with 58.45% of these cases corresponding to tinea capitis, followed by skin (tinea corporis and tinea pedis) and toenail (tinea unguium) lesions; zoophilic fungi predominated. Microsporum canis and Trichophyton mentagrophytes complex were isolated in 53.66% and 24.39% of the cases, respectively. Regarding cutaneous candidosis, 9.1% of the specimens tested positive for this disease, with 59.16% and 12.7% of the cases corresponding to toenails and interdigitoplantar lesions, respectively. Candida albicans caused 70.43% of the lesions. The remaining specimens (85.7%) tested positive for pityriasis versicolor; children aged between 6 and 12 were the most affected (71.79%). CONCLUSION: Our results agree with most epidemiological studies carried out in Brazil and demonstrate the high frequency of mycoses in preschoolers and school children, a result of poor personal hygiene and favourable weather conditions in Northern Mato Grosso, Brazil.

Development and statistical assessment of a paper-based immunoassay for detection of tumor markers.

Paper-based assays are an attractive low-cost option for clinical chemistry testing, due to characteristics such as short time of analysis, low consumption of samples and reagents, and high portability of assays. However, little attention has been given to the evaluation of the performance of these simple tests, which should include the use of a statistical approach to define the choice of best cut-off value for the test. The choice of the cut-off value impacts on the sensitivity and specificity of the bioassay. Here, we developed a paper-based immunoassay for the detection of the carcinoembryonic antigen (CEA) and performed a statistical assessment to establish the assay's cut-off value using the Youden's J index (68.28 A.U.), what allowed for a gain in sensibility (0.86) and specificity (1.0). We also discuss about the importance of defining a gray zone as a safety margin for test (±12% over the cut-off value), eliminating all false positives and false negatives outcomes and avoiding misleading results. The test accuracy was calculated as the area under the curve (AUC) of the receiver operating characteristic (ROC) curve, presenting a value of 0.97, what classifies this test as highly accurate. We propose here a low-cost method capable of detecting carcinoembryonic antigen (CEA) in human serum samples, highlighting the importance of statistical tools to evaluate a new low-cost diagnostic method.

Paper-Based Microfluidics Immunoassay for Detection of Canine Distemper Virus

ABSTRACT Paper-based devices present low-cost and are versatile, making them very attractive for clinical analysis. To manufacture those devices wax patterns are printed on paper surface and upon heating the wax permeates through the entire thickness of the paper, creating hydrophobic barriers that delimit test areas. Antibodies produced in rabbits against canine distemper virus (CDV) were physically adsorbed on the surface of gold nanoparticles (AuNPs) and incubated with CDV viral antigens, forming the immunocomplex. Anti-CDV antibodies were immobilized into the microchannels by physical adsorption, forming the test region. The test solution containing conjugated AuNPs was applied at the bottom of the microchannel and it was eluted with a phosphate buffer solution 0.01 M pH 7.4. When the solution containing the AuNPs reached the test zone the recognition of antigens contained on the immunocomplex occurred with the consequent development of a red line, which represents a positive outcome for the test. This method demonstrated the success of physical immobilization of antibodies on AuNPs and the physical immobilization of antibodies on cellulose's surface. This colorimetric assay brings simplicity and versatility to clinical analyses, presenting potential for CDV diagnosis.

Enolase from Paracoccidioides brasiliensis: isolation and identification as a fibronectin-binding protein.

Paracoccidioides brasiliensis yeast cells can enter mammalian cells and may manipulate the host cell environment to favour their own growth and survival. Moreover, fibronectin and several other host extracellular matrix proteins are recognized by various components of the yeast cell extracts. The present study was designed to isolate and characterize a fibronectin-binding protein from P. brasiliensis. We also compared P. brasiliensis strain 18, tested before (Pb18a) and after (Pb18b) animal passage, in relation to its adhesion and invasion processes. Extracts from both samples, when cultured on blood agar solid medium, showed higher levels of protein expression than when the same samples were cultured on Fava-Netto solid medium, as demonstrated by two-dimensional electrophoresis and SDS-PAGE. Also, both Pb18a and Pb18b exhibited stronger adhesion to A549 epithelial cells when cultured on blood agar medium than when cultured on Fava-Netto medium. Ligand affinity binding assays revealed a protein of 54 kDa and pI 5.6 in P. brasiliensis cell-free extracts with the properties of a fibronectin-binding adhesin, which was characterized by tryptic digestion and mass spectroscopy as a homologue of enolase from P. brasiliensis. Antibody raised against this 54 kDa protein abolished 80 % of P. brasiliensis adhesion to A549 epithelial cells. Our results demonstrate that P. brasiliensis produces a fibronectin-binding adhesin, irrespective of the culture medium, and that this activity can be inhibited by a specific antibody and is involved in the adhesion of the fungus to pulmonary epithelial cells.

Interactions of Paracoccidioides brasiliensis with host cells: recent advances.

Host-fungal interactions are inherently complex and dynamic. In order to identify new microbial targets and develop more effective antifungal therapies, it is important to understand the cellular and molecular mechanisms of disease. Paracoccidioidomycosis provokes a variety of clinical symptoms, and Paracoccidioides brasiliensis can reach many tissues, but primarily attacks the lungs. The ability of the pathogen to interact with the host surface structures is essential to further colonization, invasion, and growth. Epithelial cells may represent the first host barrier or the preferential site of entry of the fungus. For this reason, interactions between P. brasiliensis and Vero/A549 epithelial cells were evaluated, with an emphasis on the adherence, induction of cytoskeletal alterations, and differential signaling activity of the various surface molecules. The adhesion to and invasion of epithelial cells by P. brasiliensis may represent strategies employed to thwart the initial host immune response, and may help in the subsequent dissemination of the pathogen throughout the body.