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241.
Bacillus Calmette-Guérin vaccination reduces the severity and progression of tuberculosis in badgers
Chambers MA Rogers F Delahay RJ Lesellier S Ashford R Dalley D Gowtage S Davé D Palmer S Brewer J Crawshaw T Clifton-Hadley R Carter S Cheeseman C Hanks C Murray A Palphramand K Pietravalle S Smith GC Tomlinson A Walker NJ Wilson GJ Corner LA Rushton SP Shirley MD Gettinby G McDonald RA Hewinson RG 《Proceedings. Biological sciences / The Royal Society》2011,278(1713):1913-1920
Control of bovine tuberculosis (TB) in cattle has proven particularly challenging where reservoirs of infection exist in wildlife populations. In Britain and Ireland, control is hampered by a reservoir of infection in Eurasian badgers (Meles meles). Badger culling has positive and negative effects on bovine TB in cattle and is difficult, costly and controversial. Here we show that Bacillus Calmette-Guérin (BCG) vaccination of captive badgers reduced the progression, severity and excretion of Mycobacterium bovis infection after experimental challenge. In a clinical field study, BCG vaccination of free-living badgers reduced the incidence of positive serological test results by 73.8 per cent. In common with other species, BCG did not appear to prevent infection of badgers subjected to experimental challenge, but did significantly reduce the overall disease burden. BCG vaccination of badgers could comprise an important component of a comprehensive programme of measures to control bovine TB in cattle. 相似文献
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Waltemath D Adams R Beard DA Bergmann FT Bhalla US Britten R Chelliah V Cooling MT Cooper J Crampin EJ Garny A Hoops S Hucka M Hunter P Klipp E Laibe C Miller AK Moraru I Nickerson D Nielsen P Nikolski M Sahle S Sauro HM Schmidt H Snoep JL Tolle D Wolkenhauer O Le Novère N 《PLoS computational biology》2011,7(4):e1001122
245.
Michael B. Jackson Paul A. Attwood Robert W. Brailsford David Coupland Mark A. Else Philippa J. English Jacky E. Summers 《Plant and Soil》1994,167(1):99-107
Two aspects of root to shoot communication in flooded plants are discussed (i) the formation of porous aerenchyma that enhances the passage of oxygen, and other gases, from shoots to roots and (ii) the movement of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) from roots to shoots in the transpiration stream, and the effect of this on ethylene production and epinastic curvature in the shoots. For aerenchyma studies a highly sensitive photoacoustic laser detector for ethylene was used to avoid interference associated with other methods of ethylene measurement that require tissue excision. ACC concentrations in xylem sap were measured by physico-chemical means to ensure correct identification and account for processing losses. Solute concentrations, e.g., abscisic acid (ABA), in xylem sap are shown to be distorted by temporary contamination caused by the method used to collect sap. Concentrations of solutes in xylem sap (e.g., ACC) are also altered by changes in sap flow brought about by conventional methods of sap collection or by experimental treatments such as flooding the soil. Ways of for overcoming these problems are described together with a summary of preliminary results. 相似文献
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Barry GD Suen JY Low HB Pfeiffer B Flanagan B Halili M Le GT Fairlie DP 《Bioorganic & medicinal chemistry letters》2007,17(20):5552-5557
Protease activated receptor 2 (PAR(2)) is a G protein-coupled receptor implicated in inflammation and cancer. Only a few peptide agonists are known with greater potency than the native agonist SLIGRL-NH(2). Here we report 52 peptide agonists of PAR(2), 26 with activity at sub-micromolar concentrations, and one being iodinated for radioligand experiments. Potency was highest when the N- or C-termini of SLIGRL-NH(2) were modified, pointing to a new ligand pharmacophore model that may aid development of drug-like PAR(2) modulators. 相似文献
249.
A set of tools for the genetic manipulation of the osmotolerant yeast Zygosaccharomyces rouxii was developed. Auxotrophic mutants (ura3 leu2, ura3 ade2, ura3 leu2 ade2) derived from the CBS 732 type strain were prepared. Centromeric and episomal Z. rouxii/Escherichia coli shuttle plasmids with different marker genes (ScURA3, ZrLEU2, ZrADE2) and with multiple cloning sites were constructed, together with a plasmid enabling green fluorescent protein-tagging. A system for repeatable targeted gene deletion in Z. rouxii was established, involving first the integration of a PCR-generated loxP-kanMX-loxP cassette and second the removal of kanMX from the genome using a Z. rouxii plasmid harbouring cre recombinase. 相似文献
250.
Cytogenetic investigations of the domestic dog, Canis familiaris, were performed on the Doberman pinscher and two Boxer dogs. Conventional homogeneously stained and G-banded metaphases from peripheral blood lymphocyte cultures synchronized with amethopterin and bromodeoxyuridine were studied. These procedures permitted the unequivocal identification of all canine chromosomes. A canine chromosome idiogram was constructed on the basis of the G-banding pattern at the haploid 327-band resolution level. The secondary constrictions and tapering of the telomeric regions characteristic of several canine chromosomes are described. Q-, C-, and NOR-banding were also performed and the salient features are described. This karyotype should enhance the value of the canine species in cytogenetic investigations. 相似文献