Effects of melezitose and stachyose on adult longevity and virus persistence in Culicoides sonorensis (Diptera: Ceratopogonidae)

A wide variety of blood-feeding Diptera feed on extrafloral sugar sources such as homopteran honeydew. The significance of these sugar sources to insect survival and disease transmission is poorly known. Culicoides sonorensis, a biting midge, can survive on plant sugars but might also feed on homopteran honeydew. The survival of C. sonorensis fed 10% melezitose or 10% stachyose was compared to that of C. sonorensis fed 10% sucrose. A significantly greater number of C. sonorensis survived longer when fed melezitose than when fed either stachyose or sucrose. The effect of sugar meals on vector competence was measured using bluetongue and epizootic hemorrhagic disease viruses. There was no significant difference in viral persistence. However, if C. sonorensis feeds on homopteran honeydew in the wild, a larger number of midges could survive to transmit orbiviruses.     

Closing gaps in the human genome with fosmid resources generated from multiple individuals

The human genome sequence has been finished to very high standards; however, more than 340 gaps remained when the finished genome was published by the International Human Genome Sequencing Consortium in 2004. Using fosmid resources generated from multiple individuals, we targeted gaps in the euchromatic part of the human genome. Here we report 2,488,842 bp of previously unknown euchromatic sequence, 363,114 bp of which close 26 of 250 euchromatic gaps, or 10%, including two remaining euchromatic gaps on chromosome 19. Eight (30.7%) of the closed gaps were found to be polymorphic. These sequences allow complete annotation of several human genes as well as the assignment of mRNAs. The gap sequences are 2.3-fold enriched in segmentally duplicated sequences compared to the whole genome. Our analysis confirms that not all gaps within 'finished' genomes are recalcitrant to subcloning and suggests that the paired-end-sequenced fosmid libraries could prove to be a rich resource for completion of the human euchromatic genome.     

Transiting extrasolar planetary candidates in the Galactic bulge

More than 200 extrasolar planets have been discovered around relatively nearby stars, primarily through the Doppler line shifts owing to reflex motions of their host stars, and more recently through transits of some planets across the faces of the host stars. The detection of planets with the shortest known periods, 1.2-2.5 days, has mainly resulted from transit surveys which have generally targeted stars more massive than 0.75 M(o), where M(o) is the mass of the Sun. Here we report the results from a planetary transit search performed in a rich stellar field towards the Galactic bulge. We discovered 16 candidates with orbital periods between 0.4 and 4.2 days, five of which orbit stars of masses in the range 0.44-0.75 M(o). In two cases, radial-velocity measurements support the planetary nature of the companions. Five candidates have orbital periods below 1.0 day, constituting a new class of ultra-short-period planets, which occur only around stars of less than 0.88 M(o). This indicates that those orbiting very close to more-luminous stars might be evaporatively destroyed or that jovian planets around stars of lower mass might migrate to smaller radii.     

Reduction of bovine pulmonary hypertension by normoxia,verapamil and hexaprenaline

Summary In calves with hypoxic pulmonary hypertension, resistance was reduced by 40±3% with normoxia, 19±4% with verapamil, and 60±1% with hexoprenaline. It is possible that the increased resistance during normoxia is due partly to vasoconstriction rather than solely to vascular thickening, and that the vasoconstriction is due to an abnormality in calcium metabolism by the hypertensive vasculature.Acknowledgments. We thank Rosann Glas, Mary Munroe, Diann Smith and Linda Panepinto for technical assistance. This work was supported by the Colorado Heart Association and by the National Institutes of Health Grants HL-05973 and HL-29237. Verapamil (Isoptin) was supplied by Knoll Pharmaceutical Co. Hexoprenaline (ST 1512 HCl, Ipradol) was supplied by Österreichische Stickstoffwerke Linz.     

Ollier disease and Maffucci syndrome are caused by somatic mosaic mutations of IDH1 and IDH2

Ollier disease and Maffucci syndrome are characterized by multiple central cartilaginous tumors that are accompanied by soft tissue hemangiomas in Maffucci syndrome. We show that in 37 of 40 individuals with these syndromes, at least one tumor has a mutation in isocitrate dehydrogenase 1 (IDH1) or in IDH2, 65% of which result in a R132C substitution in the protein. In 18 of 19 individuals with more than one tumor analyzed, all tumors from a given individual shared the same IDH1 mutation affecting Arg132. In 2 of 12 subjects, a low level of mutated DNA was identified in non-neoplastic tissue. The levels of the metabolite 2HG were measured in a series of central cartilaginous and vascular tumors, including samples from syndromic and nonsyndromic subjects, and these levels correlated strongly with the presence of IDH1 mutations. The findings are compatible with a model in which IDH1 or IDH2 mutations represent early post-zygotic occurrences in individuals with these syndromes.     

Extreme reversed sexual size dimorphism in the extinct New Zealand moa Dinornis

The ratite moa (Aves; Dinornithiformes) were massive graviportal browsers weighing up to 250 kg (ref. 1) that dominated the New Zealand biota until their extinction approximately 500 yr ago. Despite an extensive Quaternary fossil record, moa taxonomy remains problematic and currently 11 species are recognized. Three Dinornis species were found throughout New Zealand and differed markedly in size (1-2 m height at back) and mass (from approximately 34 to 242 kg). Surprisingly, ancient mitochondrial DNA sequences show that the three species were genetically indistinguishable within each island, but formed separate North and South Island clades. Here we show, using the first sex-linked nuclear sequences from an extinct species, that on each island the three morphological forms actually represent just one species, whose size varied markedly according to sex and habitat. The largest females in this example of extreme reversed sexual size dimorphism were about 280% the weight and 150% the height of the largest males, which is unprecedented among birds and terrestrial mammals. The combination of molecular and palaeontological data highlights the difficulties of analysing extinct groups, even those with detailed fossil records.