Comparison of clinico-epidemiological and radiological features in paracoccidioidomycosis patients regarding serological classification using antigens from Paracoccidioides brasiliensis complex and Paracoccidioides lutzii.

Genotyping of the genus Paracoccidioides showed its diversity and geographical distribution. Four species constituting the Paracoccidioides brasiliensis complex and Paracoccidioides lutzii are etiological agents of paracoccidioidomycosis (PCM). However, there are no studies comparing the clinical and epidemiological aspects between PCM caused by the P. brasiliensis complex and by P. lutzii. Demographic and clinical data from 81 patients with PCM-confirmed by mycological and/or histopathological examination-from Mato Grosso do Sul state (Brazil) were studied. All patients underwent serology by immunodiffusion with antigens obtained from the P. brasiliensis complex (ExoPb and gp43) and Cell Free Antigens obtained from P.lutzii (CFAPl).The cases were classified regarding their serological profile into three groups: G1: PCM patients seropositive to ExoPb and/or gp43 and seronegative to CFAPl (n = 51), assumed to have PCM caused by P. brasiliensis complex; G2: PCM patients seronegative to gp43 and seropositive to CFAPl (n = 16), with PCM caused by P. lutzii; and G3: PCM patients seropositive to ExoPb or gp43 and seropositive to CFAPl (n = 14), with undetermined serological profile, was excluded from the analyses. The Fisher's exact test or the Mann-Whitney U test, and cluster analysis according to Ward's method and Euclidean distance were used to analyze the results. Patients with serological profile suggestive of P. lutzii lived predominantly in municipalities in the Central and Southern regions of the state, while those with serological profile indicative of the P. brasiliensis complex were distributed throughout the state. No differences were found between the two groups regarding gender, age, schooling, rural work, clinical form, severity, organs involved, intensity of pulmonary involvement, degree of anemia, erythrocyte sedimentation rate values, and therapeutic response. PCM patients with serological profile suggestive of P. lutzii and PCM patients with serological profile indicative of P. brasiliensis complex showed the same clinical and radiological presentations.

The dynamics of intraguild predation in Chrysomya albiceps Wied. (Diptera: Calliphoridae): interactions between instars and species under different abundances of food

The pattern of larval interaction in blowflies confined with Chrysomya albiceps Wied. and C. rufifacies Maquart can be changed in response to the predatory behaviour of the two species to a contest-type process instead of the scramble competition that usually occurs in blowflies. Facultative predation is a frequent behaviour in C. albiceps and C. rufifacies that occurs as an alternative food source during the larval stage. In this study, we investigated the dynamics of intraguild predation by C. albiceps on other fly species in order to analyse interspecific and intraspecific survival in C. albiceps, C. megacephala and C. macellaria Fabricius. The experimental design of the study allowed us to evaluate how factors such as species, density and abundance of food influenced the survival of the calliphorid species. When C. albiceps was confined with C. megacephala or C. macellaria, only adults of C. albiceps survived at different larval densities and abundance of food. In addition, the survival of C. albiceps was higher in two-species experiments when compared to single species experiments. The implications of these results for the dynamics of C. albiceps were discussed.

O padrão de interação larval em moscas-varejeiras na presença de Chrysomya albiceps Wied. e C. rufifacies Maquart pode ser alterado em função do comportamento predatório das duas espécies, mudando a estratégia de competição do tipo explorativa para competição por interferência. A predação facultativa é um comportamento freqüente em C. albiceps e C. rufifacies durante o estágio larval. Neste estudo, investigamos a dinâmica de predação intraguilda por C. albiceps sobre outras espécies de moscas, em experimentos delineados para analisar a sobrevivência interespecífica e intraespecífica em C. albiceps, C. megacephala Fabricius e C. macellaria Fabricius. O delineamento experimental do estudo permitiu avaliar de que modo fatores como, espécies, densidade e abundância de alimento, influenciaram a sobrevivência das espécies em culturas puras e mistas. Quando C. albiceps foi confinada com C. megacephala ou C. macellaria, somente adultos de C. albiceps sobreviveram em diferentes densidades e abundância de alimento. Além disso, a sobrevivência de C. albiceps foi superior em culturas mistas se comparada aos experimentos com culturas puras. As implicações desses resultados para a dinâmica de C. albiceps foram discutidas.