An inhibitor of FtsZ with potent and selective anti-staphylococcal activity     

Haydon DJ  Stokes NR  Ure R  Galbraith G  Bennett JM  Brown DR  Baker PJ  Barynin VV  Rice DW  Sedelnikova SE  Heal JR  Sheridan JM  Aiwale ST  Chauhan PK  Srivastava A  Taneja A  Collins I  Errington J  Czaplewski LG 《Science (New York, N.Y.)》2008,321(5896):1673-1675

FtsZ is an essential bacterial guanosine triphosphatase and homolog of mammalian beta-tubulin that polymerizes and assembles into a ring to initiate cell division. We have created a class of small synthetic antibacterials, exemplified by PC190723, which inhibits FtsZ and prevents cell division. PC190723 has potent and selective in vitro bactericidal activity against staphylococci, including methicillin- and multi-drug-resistant Staphylococcus aureus. The putative inhibitor-binding site of PC190723 was mapped to a region of FtsZ that is analogous to the Taxol-binding site of tubulin. PC190723 was efficacious in an in vivo model of infection, curing mice infected with a lethal dose of S. aureus. The data validate FtsZ as a target for antibacterial intervention and identify PC190723 as suitable for optimization into a new anti-staphylococcal therapy.  相似文献   

Demographic histories and patterns of linkage disequilibrium in Chinese and Indian rhesus macaques     

Hernandez RD  Hubisz MJ  Wheeler DA  Smith DG  Ferguson B  Rogers J  Nazareth L  Indap A  Bourquin T  McPherson J  Muzny D  Gibbs R  Nielsen R  Bustamante CD 《Science (New York, N.Y.)》2007,316(5822):240-243

To understand the demographic history of rhesus macaques (Macaca mulatta) and document the extent of linkage disequilibrium (LD) in the genome, we partially resequenced five Encyclopedia of DNA Elements regions in 9 Chinese and 38 captive-born Indian rhesus macaques. Population genetic analyses of the 1467 single-nucleotide polymorphisms discovered suggest that the two populations separated about 162,000 years ago, with the Chinese population tripling in size since then and the Indian population eventually shrinking by a factor of four. Using coalescent simulations, we confirmed that these inferred demographic events explain a much faster decay of LD in Chinese (r(2) approximately 0.15 at 10 kilobases) versus Indian (r(2) approximately 0.52 at 10 kilobases) macaque populations.  相似文献   

Natural daylight restricted to twilights delays the timing of testicular regression but does not affect the timing of the daily activity rhythm of the house sparrow (Passer domesticus)     

Amit K Trivedi  Sangeeta Rani  Vinod Kumar 《Journal of circadian rhythms》2006,4(1):5-7

Background  

A stable and systematic daily change in light levels at dawn and dusk provides the most reliable indicator of the phase of the day. It is likely that organisms have evolved mechanisms to use these twilight transitions as the primary zeitgeber to adjust their circadian phases. In this study, we investigated under natural illumination conditions the effects of daylight exposure restricted to twilights on the timing of testicular regression and locomotor activity of the house sparrow (Passer domesticus), which possesses a strongly self-sustaining circadian system.  相似文献   

Segmental inertial properties in dogs determined by magnetic resonance imaging     

Amit T  Gomberg BR  Milgram J  Shahar R 《Veterinary journal (London, England : 1997)》2009,182(1):94-99

Data regarding the segmental inertial properties of the dog are currently unavailable, although such parameters are needed for dynamic analyses of canine motion. The purpose of this study was to measure the segmental inertial properties in three medium sized dogs of average build using magnetic resonance imaging. The parameters included the mass, location of centre of mass and moments of inertia for each body segment. The normalised results will serve as a preliminary foundation for various biomechanical studies in dogs, although further study is required to characterise them for specific dog breeds and to determine how they may be affected by age and gender.  相似文献