Temporal dynamics of human mastadenovirus species in cases of respiratory illness in southern Brazil

Human mastadenovirus (HAdV) genus is related to several diseases, among them upper and lower respiratory tract illness. HAdV species B, C, D, and E are mainly associated with respiratory infections. The goal of this work was to identify the HAdV species associated with respiratory infections in hospitalized patients from southern Brazil. Samples were collected from 1996 to 2004 and 2011 to 2017. During this period, 28,524 samples were collected, and 9983 were positive for respiratory viruses, being 435 for HAdV. From these 435 samples, 57 were selected for characterization of HAdV species. For screening the presence of HAdV, a partial sequence of the DNA polymerase gene (DNApol gene) was amplified by nested PCR. Partial nucleotide sequencing was performed in positive samples, and HAdV (DNApol gene) was detected in 53 samples: species B (28;49.1%), C (16;8.0%), D (2; 3.5%), E (5; 8.7%), and untyped (2; 3.5%). Specie D was found only in 2017 and specie E in 2011 and 2012. The age of the patients ranged from < 1 to 81 years old, and 62.3%were male. No relationship between gender orage and identified HAdV species were observed. In addition, in the period of 2013­2017, 18 samples from patients who died were analyzed: 11 were related to species B, 4 to C, and 2 to D and 1 remained untyped. Circulation of HAdV species D and Evaried over the years, but species B and C were present throughout the evaluated period. In addition, respiratory infections by HAdVaffect elderly and children mainly. (AU)

Cytotoxicity and antiviral activity evaluation of Cymbopogon spp hydroethanolic extracts

Cymbopogon citratus and C. nardus are noteworthy among the several existing plant species displaying medicinal properties, due to the potential pharmacological activity of these species, including antiviral, antibacterial, antifungal and anti-trypanosomal activities. The objective of this study was to carry out in vitro toxicity tests of plant extracts from both species and analyze potential antiviral activity against Human mastadenovirus serotype 5 (HAdV-5). Two cell lines (A549 and VERO) were used and mitochondrial and lysosomal viability were determined by the MTT and neutral red assay, respectively, after two exposure times (24 hours and six days). The aim of these assays was to counteract the behavior of the extracts against the different cell lines and determine their non-toxic concentration range, in order to evaluate possible antiviral activity against HAdV-5. Plaque reduction and inhibition index of viral titer assays were performed using the maximum non-cytotoxic concentrations (MNCC) of each extract. The results indicate MNCC at 625 µg/mL for all extracts, except for Cymbopogon nardus obtained with 80% ethanol (CN80), which showed toxicity at concentrations higher than 312.5 µg/mL. CN80 was the only extract that displayed potential activity against HAdV-5, at a concentration of 75 µg/mL, becoming a candidate for extract fraction purification and/or the isolation of substances related to the observed antiviral activity