Dengue fever: a post-epidemic sero-epidemiological survey in an urban setting at a northwestern county of S. Paulo State - Brazil

Objective The objective of this study was to evaluate the real size of the epidemics registered in thr urban area of the county of Santa Barbara D'Oeste, SP Brazil, from April to June, 1995. The measurement of the epidemiological validity of the official surveillance system criteria and its positive predicted value It were adopted as specific goals. Methods A sero-epidemiological sun,ey was carried out over a sample of 1,113 sera from citizens of Santa Barbara D'Oeste, through a systematic random sampling of houses, five months after the end of the epidemics. Infection rates were compared with the infestation indexes by Aedes aegipty and the notified cases amongst the county sections. The importance of submitting patients with clinical suspicion of dengue to laboratory rests was discussed. Results and Discussion it was found that infection rates by dengue virus varied in the same direction and proportion as the presence of Aedes aegipty larvae reported by the 'Breteau Index', as well as the number of cases,reported by the official notifiable diseases surveillance system during the epidemics. A prevalence of 630 by 100 thousand inhabitants was found, a 15-fold rate when compared to rite laboratory positive sera from cases detected by the surveillance system during the epidemics. A retrospective comparison with the surveillance reports, using serological results as a gold standard, also showed that the majority of dengue specific serum-positive individuals were not detected during the epidemics. otherwise cases that did not present serological reaction were notified exhibiting a low positive predictive value of clinical diagnosis (15,6).33656657

Edible Ectomycorrhizal Mushroom Molecular Response to Heavy Metals

Heavy metal pollution poses a significant threat to the environment, public, and soil health. Ectomycorrhizal fungi are thought to enhance mineral nutrition of their host plants and to confer increased tolerance toward toxic metals. The responses of mycorrhizal fungi to toxic metal cations are diverse and may consist of a reduced uptake of metals by extracellular or intracellular chelation or increased efflux out of the cell or into sequestering compartments. Rhizosphere chemistry is critical to understanding the interactions of mycorrhizae with polluted soils. This, linked to the fact that mycorrhizal diversity is normally high, even on highly contaminated sites, suggests that this diversity may have a significant role in colonization of contaminated sites by ectomycorrhizal fungi. However, the molecular mechanisms underlying the response of ectomycorrhizal fungi to heavy metals in general remain poorly understood, although the recent Tuber melanosporum Vittad. genome sequencing and transcriptome analyses have obtained a global view of metal homeostasis-related genes and pathways in this fungus. The focus of this review is to describe and discuss the tolerance of the ectomycorrhizal fungi, in particular the edible ones, under heavy metal stress conditions