Late Onset of the Serological Response against the 18 kDa Small Heat Shock Protein of Mycobacterium ulcerans in Children

A previous survey for clinical cases of Buruli ulcer (BU) in the Mapé Basin of Cameroon suggested that, compared to older age groups, very young children may be less exposed to Mycobacterium ulcerans. Here we determined serum IgG titres against the 18 kDa small heat shock protein (shsp) of M. ulcerans in 875 individuals living in the BU endemic river basins of the Mapé in Cameroon and the Densu in Ghana. While none of the sera collected from children below the age of four contained significant amounts of 18 kDa shsp specific antibodies, the majority of sera had high IgG titres against the Plasmodium falciparum merozoite surface protein 1 (MSP-1). These data suggest that exposure to M. ulcerans increases at an age which coincides with the children moving further away from their homes and having more intense environmental contact, including exposure to water bodies at the periphery of their villages.     

Methodological problems related to spotlight count as a census technique for Lepus europaeus in an alpine environment

Population estimations are necessary for effective conservation management. In Italy, brown hare populations are commonly censused by spotlighting, but this method does not seem to suit an alpine environment due to its vegetational and orographical complexity. The aim of this study is to evaluate the critical aspects related to spotlight census method in an alpine environment. Spotlight was carried out along two transects of a typical alpine environment. Observed animals were used to define density (number of animal seen/100 ha) and method precision (coefficient of variation (CV) applied to monthly repeated observations). Animal detectability was evaluated using half-normal function with cosine expansion (Distance 5.0®). Animal observability was evaluated by analyzing density estimates related to habitat conformation (unseen areas or full visibility). The exact surface surveyed by spotlighting was evaluated, defining the observation spotlight beam range (OTA) and the land useful sighting (LUS). In the end, LUS was classified in three patches according to hare presence: no hares, occasional hare presence, and constant hare presence. To evaluate habitat influence onto CV, we used a bootstrap simulation. The results show that spotlighting alone is not the most suitable method to apply in the alpine environment because habitat structure highly influences census results. Recommendations to improve spotlight surveys for monitoring European brown hare populations are given.     

Oxygen and carbon isotope variations in Chamelea gallina shells: Environmental influences and vital effects

Stable isotopes in mollusc shells, together with variable growth rates and other geochemical properties, can register different environmental clues, including seawater temperature, salinity and primary productivity. However, the strict biological control over the construction of biominerals exerted by many calcifying organisms can constrain the use of these organisms for paleoenvironmental reconstructions. Biologically controlled calcification is responsible for the so called vital effects that cause a departure from isotopic equilibrium during shell formation, resulting in lower shell oxygen and carbon compared to the equilibrium value. We investigated shell oxygen and carbon isotopic composition of the bivalve Chamelea gallina in six sites along with a latitudinal gradient on the Adriatic Sea (NE Mediterranean Sea). Seawater δ¹⁸O and δ¹³C_DIC varied from North to South, reflecting variations in seawater temperature, salinity, and chlorophyll concentration among sites. Shell δ¹⁸O and δ¹³C differed among sites and exhibited a wide range of values along with the ~400 km latitudinal gradient, away from isotopic equilibrium for both isotopes. These results hampered the utilization of this bivalve as a proxy for environmental reconstructions, in spite of C. gallina showing promise as a warm temperature proxy. Rigorous calibration studies with a precise insight of environment and shell growth are crucial prior to considering this bivalve as a reliable paleoclimatic archive.     

Ectopic expression of Kxhkn5 in the viviparous species Kalanchoe?��?Houghtonii induces a novel pattern of epiphyll development

KxhKN5 (class 1 KNOX gene) was cloned from Kalanchoe × houghtonii with strong tendency to form epiphylls on leaves. KxhKN5 appear to be homologue of BP of A. thaliana on the basis of phylogeny, expression and phenotype analysis. Beside the modification of several plant and leaf traits, the appearance of epiphylls was drastically reduced by both the silencing and the over-expression of KxhKN5 in most of the generated clones. In silenced clones, epiphyll production followed the morphogenetic pathway of the WT plants: somatic embryos outbreak in the centre of each leaf-pedestal, grown in the notch between leaf indentations and were supported by a suspensor. The connection between the epiphyll and the mother plant did not include any vasculature and as a result, the epiphylls dropped easily from the mother plant. The most represented category of over expressor clones, disclosed a novel pattern of epiphyll development: the leaf-pedestals were absent and single bud outbreaks in each leaf notch. Buds developed into shoots which remained attached to the maternal plant by a strong vascular connection. The leaves supporting shoots, produced a thickened midrib and veins, and their lamina ceased expanding. Finally, the leaf/shoot structure resembles a lateral branch. The ectopic expression of KxhKN5 in K. × houghtonii induces a process comparable to the alternation of leaf and shoot formation in other species and support the idea, that it is the variation in shared molecular and developmental processes which produces the growth of specific structures.