An optimized microarray platform for assaying genomic variation in <Emphasis Type="Italic">Plasmodium falciparum</Emphasis> field populations

We present an optimized probe design for copy number variation (CNV) and SNP genotyping in the Plasmodium falciparum genome. We demonstrate that variable length and isothermal probes are superior to static length probes. We show that sample preparation and hybridization conditions mitigate the effects of host DNA contamination in field samples. The microarray and workflow presented can be used to identify CNVs and SNPs with 95% accuracy in a single hybridization, in field samples containing up to 92% human DNA contamination.     

Aerobic fitness and performance in elite female futsal players

Despite its growing popularity, few studies have investigated specific physiological demands for elite female futsal. The aim of this study was to determine aerobic fitness in elite female futsal players using laboratory and field testing. Fourteen female futsal players from the Venezuelan National team (age =21.2±4.0 years; body mass =58.6±5.6 kg; height =161±5.0 cm) performed a progressive maximal treadmill test under laboratory conditions. Players also performed a progressive intermittent futsal-specific field test for endurance, the Futsal Intermittent Endurance Test (FIET), until volitional fatigue. Outcome variables were exercise heart rate (HR), VO₂, post-exercise blood lactate concentrations ([La]b) and running speeds (km · h^-1). During the treadmill test, VO₂max, maximal aerobic speed (MAS), HR and peak [La]b were 45.3±5.6 ml · kg^-1 · min^-1, 12.5±1.77 km · h^-1, 197±8 beats · min^-1 and 11.3±1.4 mmol · l^-1, respectively. The FIET total distance, peak running velocity, peak HR and [La]b were 1125.0±121.0 m, 15.2±0.5 km · h^-1, 199±8 beats · min^-1 and 12.5±2.2 mmol · l^-1, respectively. The FIET distance and peak speed were strongly associated (r= 0.85-87, p < 0.0001) with VO₂max and MAS, respectively. Peak HR and [La]b were not significantly different between tests. Elite female futsal players possess moderate aerobic fitness. Furthermore, the FIET can be considered as a valid field test to determine aerobic fitness in elite level female futsal players.     

Sleep deprivation sensitizes human craniofacial muscles

It is unknown whether and how sleep deprivation influences craniofacial muscle sensitivity in healthy humans. We investigated whether total sleep deprivation (TSD) and one night of recovery sleep (RS) can alter mechanical pain sensitivity in temporal and masseter muscles. Fifteen healthy volunteers participated in three consecutive sessions. Pressure pain thresholds were measured on the temporal and masseter muscles. Both temporal and masseter muscles became sensitized after 24?h of TSD. RS reversed the muscle sensitization.     

Deregulated Nras Expression in Knock-In Animals Harboring a Gammaretroviral Long Terminal Repeat at the Nras/Csde1 Locus

To investigate mechanisms and phenotypic effects of insertional mutagenesis by gammaretroviruses, we have developed mouse lines containing a single Akv 1-99 long terminal repeat (LTR) and a floxed PGK/Tn5 neomycin cassette at the Nras proto-oncogene at positions previously identified as viral integration sites in Akv 1-99 induced tumors. The insert did not compromise the embryonic development, however, the cassette had an effect on Nras expression in all tissues analyzed. Cre-mediated excision of the PGK/Tn5 neomycin cassette in two of the lines caused upregulation of Nras. Altogether, the knock-in alleles are characterized by modulation of expression of the target gene from more than ten-fold upregulation to three-fold downregulation and exemplify various mechanisms of deregulation by insertional mutagenesis. LTR knock-in mice may serve as a tool to investigate mechanisms of retroviral insertional mutagenesis and as a way of constitutive or induced modulation of expression of a target gene.     

DNA hybridization evidence for the principal lineages of hummingbirds (Aves:Trochilidae)

The spectacular evolutionary radiation of hummingbirds (Trochilidae) has served as a model system for many biological studies. To begin to provide a historical context for these investigations, we generated a complete matrix of DNA hybridization distances among 26 hummingbirds and an outgroup swift (Chaetura pelagica) to determine the principal hummingbird lineages. FITCH topologies estimated from symmetrized delta TmH-C values and subjected to various validation methods (bootstrapping, weighted jackknifing, branch length significance) indicated a fundamental split between hermit (Eutoxeres aquila, Threnetes ruckeri; Phaethornithinae) and nonhermit (Trochilinae) hummingbirds, and provided strong support for six principal nonhermit clades with the following branching order: (1) a predominantly lowland group comprising caribs (Eulampis holosericeus) and relatives (Androdon aequatorialis and Heliothryx barroti) with violet-ears (Colibri coruscans) and relatives (Doryfera ludovicae); (2) an Andean-associated clade of highly polytypic taxa (Eriocnemis, Heliodoxa, and Coeligena); (3) a second endemic Andean clade (Oreotrochilus chimborazo, Aglaiocercus coelestis, and Lesbia victoriae) paired with thorntails (Popelairia conversii); (4) emeralds and relatives (Chlorostilbon mellisugus, Amazilia tzacatl, Thalurania colombica, Orthorhyncus cristatus and Campylopterus villaviscensio); (5) mountain-gems (Lampornis clemenciae and Eugenes fulgens); and (6) tiny bee-like forms (Archilochus colubris, Myrtis fanny, Acestrura mulsant, and Philodice mitchellii). Corresponding analyses on a matrix of unsymmetrized delta values gave similar support for these relationships except that the branching order of the two Andean clades (2, 3 above) was unresolved. In general, subsidiary relationships were consistent and well supported by both matrices, sometimes revealing surprising associations between forms that differ dramatically in plumage and bill morphology. Our results also reveal some basic aspects of hummingbird ecologic and morphologic evolution. For example, most of the diverse endemic Andean assemblage apparently comprises two genetically divergent clades, whereas the majority of North American hummingbirds belong a single third clade. Genetic distances separating some morphologically distinct genera (Oreotrochilus, Aglaiocercus, Lesbia; Myrtis, Acestrura, Philodice) were no greater than among congeneric (Coeligena) species, indicating that, in hummingbirds, morphological divergence does not necessarily reflect level of genetic divergence.