FOREST SYSTEMS, SOIL FAUNA, AND SOIL FEATURES: HOW FIELD MANAGEMENT CHANGE THIS RELATIONSHIP?

The objective of this study was to identify differences in land use systems and forest management on the diversity of soil fauna and Collembola eco-morphotypes, and their relationship with physical-chemical attributes of the soil. Sampling was carried out in Native Forest (NF), Araucaria Reforestation (AR) and Eucalyptus (ER). In all, 19 taxonomic groups were identified, of which Formicidae and Collembola were the most abundant, in addition to 21 morphotypes of springtail. For TSBF, AR presented the highest abundance and NF the highest values of wealth and diversity of groups. Potassium and magnesium contents, total porosity, pore volume, penetration resistance (Rpen), organic matter, and pH were the environmental variables that contributed to explain the distribution of the soil fauna. In pitfalls traps, ER showed the greatest abundance, NF the greatest richness and AR the greatest diversity. Rpen and soil moisture contributed to explain the distribution of soil fauna. NF provided greater abundance, diversity, and richness of Collembola eco-morphotypes and biopores, macropores, clay, manganese and copper levels affected the community structure. Different forest systems affect the structure of the soil community, showing improvement in biological indicators in the Native Forest areas, Araucaria, and Eucalyptus Reforestation, under the influence of physical and chemical attributes

Saprochaete clavata invasive infection: characterization, antifungal susceptibility, and biofilm evaluation of a rare yeast isolated in Brazil

Rare emerging pathogens such as Saprochaete clavata are associated with invasive fungal diseases, high morbidity, mortality, rapidly fatal infections, and outbreaks. However, little is known about S. clavata infections, epidemiology, risk factors, treatment, biofilms, and disease outcomes. The objective of this study was to describe a new case of severe S. clavata infection in a patient diagnosed at a referral children’s hospital in Brazil, including antifungal minimal inhibitory concentration, S. clavata biofilm characterization, and molecular characterization. The S. clavata isolated from an immunocompromised 11-year-old male patient was characterized using MALDI-TOF, Gram staining, scanning electron microscopy (SEM), and next generation sequencing (NGS) of genomic DNA. Biofilm production was also evaluated in parallel with determining minimal inhibitory concentration (MIC) and biofilm sensitivity to antifungal treatment. We observed small to medium, whitish, farinose, dry, filamentous margin colonies, yeast-like cells with bacillary features, and biofilm formation. The MALDI-TOF system yielded a score of ≥ 2,000, while NGS confirmed S. clavata presence at the nucleotide level. The MIC values (in mg L-1) for tested drugs were as follows: fluconazole = 2, voriconazole ≤ 2, caspofungin ≥ 8, micafungin = 2, amphotericin B = 4, flucytosine ≤ 1, and anidulafungin = 1. Amphotericin B can be active against S. clavata biofilm and the fungus can be susceptible to new azoles. These findings were helpful for understanding the development of novel treatments for S. clavata-induced disease, including combined therapy for biofilm-associated infections

Os primeiros turbiditos do Brasil

No sul do Paraná e boa parte do estado de Santa Catarina aflora uma sucessão de arenitos e ritmitos de idade eopermiana, cuja gênese está relacionada à ação de correntes de turbidez. Esses depósitos foram identificados por Salamuni e colaboradores em 1966, sendo assim os primeiros turbiditos descritos no Brasil. No entanto, esse trabalho pioneiro tem sido esquecido na literatura geológica brasileira. O intervalo turbidítico situa-se no Membro Rio Segredo da Formação Taciba, terço superior do Grupo Itararé, Bacia do Paraná. As fácies incluem desde turbiditos delgados em camadas centimétricas de arenito muito fino que grada para folhelho até camadas mais espessas, até mesmo métricas, de arenitos tabulares, frequentemente amalgamados. Estruturas de sobrecarga, marcas basais de arraste e impacto de detritos, turboglifos, aspecto dominantemente maciço, feições de escape de fluidos, estrados gradados e deformação plástica penecontemporânea formam conjunto de evidências que corrobora a atividade de fluxos gravitacionais. Além disso, a associação repousa sobre o folhelho Lontras, cujas fácies, atributos geoquímicos e conteúdo fossilífero indicam deposição em ambiente marinho restrito, de baixa oxigenação e relativamente profundo. A sucessão acima dos turbiditos registra ainda a progradação de taludes deltaicos suscetíveis a escorregamentos, que culminam com sedimentação fluvial e costeira já pertencente à Formação Rio Bonito. As relações estratigráficas permitem concluir que os turbiditos compõem um complexo com no mínimo 220 km de extensão lateral, desenvolvido durante a progradação de deltas que preencheram a bacia após seu máximo afogamento causado pela deglaciação do final do Pensilvaniano. Em subsuperfície, os arenitos turbidíticos são potenciais reservatórios para hidrocarboneto gerado em folhelhos do Devoniano da Bacia do Paraná. Podem ainda constituir bons análogos de afloramento para reservatórios turbidíticos inseridos em cunhas progradacionais de outras bacias

Genotypic Diversity of <i>Candida parapsilosis</i> Complex in Invasive Candidiasis at a Pediatric Tertiary Hospital: A 5-Year Retrospective Study

Invasive candidiasis (IC) contributes to the morbidity and mortality of hospitalized patients and represents a significant burden to the healthcare system. Previous Brazilian studies have reported the presence of endemic Candida parapsilosis sensu stricto genotypes causing candidemia and clonal transmission involving fluconazole-resistant isolates. We performed a 5-year retrospective analysis of IC cases in a Brazilian tertiary pediatric hospital and conducted a molecular investigation of C. parapsilosis sensu stricto. Non-duplicate C. parapsilosis sensu stricto genotyping was performed by microsatellite analysis. Antifungal susceptibility and biofilm formation were also evaluated. A total of 123 IC episodes were identified, with an IC incidence of 1.24 cases per 1000 hospital admissions and an overall mortality of 34%. The main species were the C. parapsilosis complex (35.8%), Candida albicans (29.2%), and Candida tropicalis (21.9%). All C. parapsilosis sensu stricto were recovered from blood cultures, and 97.5% were biofilm producers. Microsatellite typing identified high genotypic diversity among the isolates. We observed that all isolates were sensitive to amphotericin B, and although one isolate was non-sensitive to fluconazole, only a silent mutation on ERG11 gene was identified. No clear evidence of clonal outbreak or emergence of fluconazole-resistant isolates was found, suggesting that multiple sources may be involved in the epidemiology of IC in children