Species pool size alters species-area relationships during experimental community assembly.

The species pool concept has advanced our understanding for how biodiversity is coupled at local and regional scales. However, it remains unclear how species pool size, the number of species available to disperse to a site, influences community assembly across spatial scales. We provide one of the first studies that assesses diversity across scales after experimentally assembling grassland communities from species pools of different sizes. We show that species pool size causes scale-dependent effects on diversity in grasslands undergoing restoration by altering the shape of the species-area relationship (SAR). Specifically, larger species pools increased the slope of the SAR, but not the intercept, suggesting that dispersal from a larger pool causes species to be more spatially aggregated. This increased aggregation appears to be caused by sampling effects due to fewer individuals arriving per species, rather than stronger species sorting across variation in soil moisture. These scale-dependent effects suggest that studies evaluating species pools at a single, small scale may underestimate their effects, thereby contributing to uncertainty about the importance of regional processes for community assembly and their consequences for ecological restoration.

Hypersensitivity to non-steroidal anti-inflammatory drugs in childhood.

Although largely investigated in adults, the issue of hypersensitivity to non-steroidal anti-inflammatory drugs (NSAIDs) in childhood is unsettled due to lack of sufficient data. The purpose of this study is to examine the clinical syndromes of hypersensitivity to NSAIDs in children and adolescents. We performed a review of relevant papers on cutaneous and respiratory adverse reactions triggered by NSAIDs in pediatric patients, and a recount of our own experience in 43 well-characterized NSAID-sensitive children with cutaneous reactions who were submitted to controlled oral challenges with NSAIDs and the new inhibitors of the enzyme isoform cyclooxygenase-2 (COX-2). Although it has been suggested that allergic and pseudoallergic reactions to NSAIDs in children occur rarely, their prevalence remains largely unknown due to the scarcity of studies. About 23% of NSAID-sensitive patients seen in our institutions are young patients aged 8-18 yr who more frequently develop facial angioedema as their main clinical manifestation. Most patients are atopic and show reactions to more than one drug (cross-reactors). Drugs that inhibit COX-2 with higher specificity than classic NSAIDs are better tolerated in young NSAID-hypersensitive patients.

Aproximación al problema de la alergía al latex en Venezuela / Approach to the problem of the allergy to the latex in Venezuela

Después de una historia breve sobre el latéx, se aplican los posibles síntomas alérgicos que este material puede producir tanto en pacientes como el personal médico y paramédico. Se expone la experiencia personal al respecto