Targeting essential pathways in trypanosomatids gives insights into protozoan mechanisms of cell death.

Apoptosis is a normal component of the development and health of multicellular organisms. However, apoptosis is now considered a prerogative of unicellular organisms, including the trypanosomatids of the genera Trypanosoma spp. and Leishmania spp., causative agents of some of the most important neglected human diseases. Trypanosomatids show typical hallmarks of apoptosis, although they lack some of the key molecules contributing to this process in metazoans, like caspase genes, Bcl-2 family genes and the TNF-related family of receptors. Despite the lack of these molecules, trypanosomatids appear to have the basic machinery to commit suicide. The components of the apoptotic execution machinery of these parasites are slowly coming into light, by targeting essential processes and pathways with different apoptogenic agents and inhibitors. This review will be confined to the events known to drive trypanosomatid parasites to apoptosis.

Origine des populations de rainette verte (Hyla spp.) de l'ouest de la Suisse

DNA-based techniques are important tools for species assignment, in particular when identification with morphological criteria is difficult. The aim of this study was to genetically determine the species identity of tree frogs (Hyla spp.) populations from western and northern Switzerland (Swiss Plateau), this area being frequently subjected to introductions of species or sub-species from south of the Alps. We sequenced 261 base pairs of the mitochondrial DNA cytochrome b gene from 24 samples of tree frogs from the Swiss Plateau, Ticino (southern Switzerland) and the Dombes region (Ain, France), and compared them with homologous sequences retrieved from DNA databases. The phylogenetic analyses revealed two distinct clades. The first one is represented by samples of Green tree frog (Hyla arborea) from the Swiss Plateau, France, Germany and Greece, confirming the current knowledge about the species' distribution. The second clade includes samples belonging to the Italian tree frog (Hyla intermedia) from south of the Alps (Ticino and Italy), and unexpectedly from the Grangettes site in western Switzerland. These results suggest the introduction of the Italian tree frog H. intermedia north of the Alps, and raise questions about the management of the Grangettes protected area.

Cardenolides, induced responses, and interactions between above- and belowground herbivores of milkweed (Asclepias spp.).

Theory has long predicted allocation patterns for plant defense against herbivory, but only recently have both above- and belowground plant defenses been considered simultaneously. Milkweeds in the genus Asclepias are a classic chemically defended clade of plants with toxic cardenolides (cardiac glycosides) and pressurized latex employed as anti-herbivore weapons. Here we combine a comparative approach to investigate broadscale patterns in allocation to root vs. shoot defenses across species with a species-specific experimental approach to identify the consequences of defense allocational shifts on a specialist herbivore. Our results show phylogenetic conservatism for inducibility of shoot cardenolides by an aboveground herbivore, with only four closely related tropical species showing significant induction; the eight temperate species examined were not inducible. Allocation to root and shoot cardenolides was positively correlated across species, and this relationship was maintained after accounting for phylogenetic nonindependence. In contrast to long-standing theoretical predictions, we found no evidence for a trade-off between constitutive and induced cardenolides; indeed the two were positively correlated across species in both roots and shoots. Finally, specialist root and shoot herbivores of common milkweed (A. syriaca) had opposing effects on latex production, and these effects had consequences for caterpillar growth consistent with latex providing resistance. Although cardenolides were not affected by our treatments, A. syriaca allocated 40% more cardenolides to shoots over roots. We conclude that constitutive and inducible defenses are not trading off across plant species, and shoots of Asclepias are more inducible than roots. Phylogenetic conservatism cannot explain the observed patterns of cardenolide levels across species, but inducibility per se was conserved in a tropical clade. Finally, given that above- and belowground herbivores can systemically alter the defensive phenotype of plants, we concur with recent calls for a whole-plant perspective in testing models of plant defense allocation.

ESCMID* guideline for the diagnosis and management of Candida diseases 2012: prevention and management of invasive infections in neonates and children caused by Candida spp.

Invasive candidiasis (IC) is a relatively common syndrome in neonates and children and is associated with significant morbidity and mortality. These guidelines provide recommendations for the prevention and treatment of IC in neonates and children. Appropriate agents for the prevention of IC in neonates at high risk include fluconazole (A-I), nystatin (B-II) or lactoferrin ± Lactobacillus (B-II). The treatment of IC in neonates is complicated by the high likelihood of disseminated disease, including the possibility of infection within the central nervous system. Amphotericin B deoxycholate (B-II), liposomal amphotericin B (B-II), amphotericin B lipid complex (ABLC) (C-II), fluconazole (B-II), micafungin (B-II) and caspofungin (C-II) can all be potentially used. Recommendations for the prevention of IC in children are largely extrapolated from studies performed in adults with concomitant pharmacokinetic data and models in children. For allogeneic HSCT recipients, fluconazole (A-I), voriconazole (A-I), micafungin (A-I), itraconazole (B-II) and posaconazole (B-II) can all be used. Similar recommendations are made for the prevention of IC in children in other risk groups. With several exceptions, recommendations for the treatment of IC in children are extrapolated from adult studies, with concomitant pharmacokinetic studies. Amphotericin B deoxycholate (C-I), liposomal amphotericin B (A-I), ABLC (B-II), micafungin (A-I), caspofungin (A-I), anidulafungin (B-II), fluconazole (B-I) and voriconazole (B-I) can all be used.

Genotype-level interactions determine the degree of reduction of leaf rust on wheat by seed application of beneficial Pseudomonas spp.

Some bacteria have the capacity to reduce incidence and severity of plant diseases either by inhibiting the pathogen or by modulating the resistance response of the plant. Plants dispose of different resistance mechanisms that are influenced by the biotic and abiotic environment. The present experiments explored the effects of biocontrol strains of Pseudomonas fluorescens on the resistance of wheat varieties against brown rust disease caused by Puccinia triticina. Root inoculation with biocontrol pseudomonads reduced the disease severity on the leaves. The plant response depended on the genotype of both the microbes and the wheat varieties, suggesting a straight interaction at the molecular level.