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1.
Stephen GS Vreden Jeetendra K Jitan Rakesh D Bansie Malti R Adhin 《Memórias do Instituto Oswaldo Cruz》2013,108(8):968-973
The emerging resistance to artemisinin derivatives that has been reported in
South-East Asia led us to assess the efficacy of artemether-lumefantrine as the first
line therapy for uncomplicated Plasmodium falciparum infections in
Suriname. This drug assessment was performed according to the recommendations of the
World Health Organization in 2011. The decreasing number of malaria cases in
Suriname, which are currently limited to migrating populations and gold miners,
precludes any conclusions on artemether efficacy because adequate numbers of patients
with 28-day follow-up data are difficult to obtain. Therefore, a comparison of day 3
parasitaemia in a 2011 study and in a 2005/2006 study was used to detect the
emergence of resistance to artemether. The prevalence of day 3 parasitaemia was
assessed in a study in 2011 and was compared to that in a study in 2005/2006. The
same protocol was used in both studies and artemether-lumefantrine was the study
drug. Of 48 evaluable patients in 2011, 15 (31%) still had parasitaemia on day 3
compared to one (2%) out of 45 evaluable patients in 2005/2006. Overall, 11 evaluable
patients in the 2011 study who were followed up until day 28 had negative slides and
similar findings were obtained in all 38 evaluable patients in the 2005/2006 study.
The significantly increased incidence of parasite persistence on day 3 may be an
indication of emerging resistance to artemether. 相似文献
2.
Susan K. Boehlein Peng Liu Ashley Webster Camila Ribeiro Masaharu Suzuki Shan Wu Jiahn‐Chou Guan Jon D. Stewart William F. Tracy A. Mark Settles Donald R. McCarty Karen E. Koch Larkin C. Hannah Tracie A. Hennen‐Bierwagen Alan M. Myers 《The Plant journal : for cell and molecular biology》2019,99(1):23-40
3.
High-copy transposon mutagenesis is an effective tool for creating gene disruptions in maize. In order to molecularly define transposon-induced disruptions on a genome-wide scale, we optimized TAIL-PCR to amplify genomic DNA flanking maize Robertson’s Mutator insertions. Sample sequencing from 43 Mutator stocks and the W22 inbred line identified 676 non-redundant insertions, and only a small fraction of the flanking sequences showed significant similarity to maize repetitive sequences. We further designed and tested 79 arbitrary primers to identify 12 primers that amplify all Mutator insertions within a DNA sample at 3.1-fold redundancy. Importantly, the products are of sufficient size to use as substrates or probes for hybridization-based identification of gene disruptions. Our adaptation simplifies previously published TAIL-PCR protocols and should be transferable to other high-copy insertional mutagens. 相似文献
4.
The thylakoidal DeltapH-dependent and bacterial twin arginine transport systems are structurally and functionally related protein export machineries. These recently discovered systems have been shown to transport folded proteins but are not known to assemble integral membrane proteins. We determined the translocation pathway of a thylakoidal FtsH homologue, plastid fusion/protein translocation factor, which is synthesized with a chloroplast-targeting peptide, a hydrophobic signal peptide, and a hydrophobic membrane anchor. The twin arginine motif in its signal peptide and its sole integration requirement of a DeltapH suggested that plastid fusion/protein translocation factor employs the DeltapH pathway. Surprisingly, changing the twin arginine to twin lysine or deleting the signal peptide did not abrogate integration capability or characteristics. Nevertheless, three criteria argue that all three forms require the DeltapH pathway for integration. First, integration was competed by an authentic DeltapH pathway precursor. Second, antibodies to DeltapH pathway component Hcf106 specifically inhibited integration. Finally, chloroplasts from the hcf106 null mutant were unable to integrate Pftf into their thylakoids. Thus, DeltapH pathway machinery facilitates both signal peptide-directed and N-tail-mediated membrane integration and does not strictly require the twin arginine motif. 相似文献
5.
Targeting of chloroplast proteins to the thylakoid membrane is analogous to bacterial secretion, and much of what we know has been learned from secretory mechanisms in Escherichia coli. However, chloroplasts also use a ΔpH-dependent pathway to target thylakoid proteins, at least some of which are folded before transport. Previously, this pathway seemed to have no cognate in bacteria, but recent results have shown that the HCF106 gene in maize encodes a component of this pathway and has bacterial homologues. This ΔpH-dependent pathway might be an ancient conserved mechanism for protein translocation that evolved before the endosymbiotic origin of plastids and mitochondria. 相似文献
6.
M. Settles R. Zanella S. D. McKay R. D. Schnabel J. F. Taylor R. Whitlock Y. Schukken J. S. Van Kessel J. M. Smith H. Neibergs 《Animal genetics》2009,40(5):655-662
The purpose of this study was to identify loci associated with Mycobacterium avium subspecies paratuberculosis ( Map ) infection status in US Holsteins using the Illumina BovineSNP50 BeadChip whole genome single nucleotide polymorphism (SNP) assay. Two hundred forty-five cows from dairies in New York, Pennsylvania and Vermont enrolled in longitudinal herd studies between January 1999 and November 2007 were assessed for the presence of Map in both faecal and tissue samples. An animal was considered tissue infected if any sample contained at least one colony forming unit of Map per gram of tissue (CFU/g) and the same definition was employed for faecal samples. Each animal was genotyped with the Illumina BovineSNP50 BeadChip and after quality assurance filtering, 218 animals and 45 683 SNPs remained. We sought to identify loci associated with four different case/control classifications: presence of Map in the tissue, presence of Map in faeces, presence of Map in both tissue and faeces and presence of Map in tissue but not faeces. A case–control genome wide association study was conducted to test the four different classifications of Map infection status (cases) when compared with a Map -negative control group (control). Regions on chromosomes 1, 5, 7, 8, 16, 21 and 23 were identified with moderate significance ( P < 5 × 10−5 ). Two regions, one on chromosome 3 (near EDN2 ) and another on chromosome 9 (no positional gene candidates), were identified with a high level of association to the presence of Map in tissue and both tissue and faeces respectively ( P < 5 × 10−7 , genome-wide Bonferonni P < 0.05). 相似文献
7.
Federico Martin Sarah Dailey A. Mark Settles 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(4):697-704
The genome sequence of the B73 maize inbred enables map-based cloning of genetic variants underlying phenotypes. In parallel
to sequencing efforts, multiple public mutagenesis resources are being developed predominantly in the W22 and B73 inbreds.
Efficient platforms to map mutants in these genetic backgrounds would aid molecular genetic analysis of the public resources.
We screened 505 simple sequence repeat markers for polymorphisms between the B73, Mo17, and W22 inbreds. Using common thermocycling
conditions, 47.1% of the markers showed co-dominant polymorphisms in at least one pair of inbreds. Based on these results,
we identified 85 distributed markers for mapping in all three inbred pairs. For each inbred pair, the distributed set has
64–71 polymorphic markers with a mean distance of 27–29 cM between markers. The distributed markers give nearly complete coverage
of the genetic map for each inbred pair. We demonstrate the utility of the marker set for efficient placement of mutants on
the maize genetic map with an example mapping experiment of a seed mutant from the UniformMu mutagenesis resource. We conclude
that these distributed molecular markers enable rapid mapping of phenotypic variants from public mutagenesis populations. 相似文献
8.
Kumaran Sivagnanam Vijaya GS Raghavan Manesh Shah Robert L Hettich Nathan C Verberkmoes Mark G Lefsrud 《Proteome science》2011,9(1):1-14
Background
Cytokinin is a plant hormone that plays a crucial role in several processes of plant growth and development. In recent years, major breakthroughs have been achieved in the elucidation of the metabolism, the signal perception and transduction, as well as the biological functions of cytokinin. An important activity of cytokinin is the involvement in chloroplast development and function. Although this biological function has already been known for 50 years, the exact mechanisms remain elusive.Results
To elucidate the effects of altered endogenous cytokinin content on the structure and function of the chloroplasts, chloroplast subfractions (stroma and thylakoids) from transgenic Pssu-ipt and 35S:CKX1 tobacco (Nicotiana tabacum) plants with, respectively, elevated and reduced endogenous cytokinin content were analysed using two different 2-DE approaches. Firstly, thykaloids were analysed by blue-native polyacrylamide gel electrophoresis followed by SDS-PAGE (BN/SDS-PAGE). Image analysis of the gel spot pattern thus obtained from thylakoids showed no substantial differences between wild-type and transgenic tobacco plants. Secondly, a quantitative DIGE analysis of CHAPS soluble proteins derived from chloroplast subfractions indicated significant gel spot abundance differences in the stroma fraction. Upon identification by MALDI-TOF/TOF mass spectrometry, these proteins could be assigned to the Calvin-Benson cycle and photoprotective mechanisms.Conclusion
Taken together, presented proteomic data reveal that the constitutively altered cytokinin status of transgenic plants does not result in any qualitative changes in either stroma proteins or protein complexes of thylakoid membranes of fully developed chloroplasts, while few but significant quantitative differences are observed in stroma proteins. 相似文献9.
SUMMARY: OTUbase is an R package designed to facilitate the analysis of operational taxonomic unit (OTU) data and sequence classification (taxonomic) data. Currently there are programs that will cluster sequence data into OTUs and/or classify sequence data into known taxonomies. However, there is a need for software that can take the summarized output of these programs and organize it into easily accessed and manipulated formats. OTUbase provides this structure and organization within R, to allow researchers to easily manipulate the data with the rich library of R packages currently available for additional analysis. AVAILABILITY: OTUbase is an R package available through Bioconductor. It can be found at http://www.bioconductor.org/packages/release/bioc/html/OTUbase.html. 相似文献
10.
Settles M Etzrodt M Kosanke K Schiemann M Zimmermann A Meier R Braren R Huber A Rummeny EJ Weissleder R Swirski FK Wildgruber M 《PloS one》2011,6(10):e25197