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91.
Glenn A. Marsh Carol de Jong Jennifer A. Barr Mary Tachedjian Craig Smith Deborah Middleton Meng Yu Shawn Todd Adam J. Foord Volker Haring Jean Payne Rachel Robinson Ivano Broz Gary Crameri Hume E. Field Lin-Fa Wang 《PLoS pathogens》2012,8(8)
The genus Henipavirus in the family Paramyxoviridae contains two viruses, Hendra virus (HeV) and Nipah virus (NiV) for which pteropid bats act as the main natural reservoir. Each virus also causes serious and commonly lethal infection of people as well as various species of domestic animals, however little is known about the associated mechanisms of pathogenesis. Here, we report the isolation and characterization of a new paramyxovirus from pteropid bats, Cedar virus (CedPV), which shares significant features with the known henipaviruses. The genome size (18,162 nt) and organization of CedPV is very similar to that of HeV and NiV; its nucleocapsid protein displays antigenic cross-reactivity with henipaviruses; and it uses the same receptor molecule (ephrin- B2) for entry during infection. Preliminary challenge studies with CedPV in ferrets and guinea pigs, both susceptible to infection and disease with known henipaviruses, confirmed virus replication and production of neutralizing antibodies although clinical disease was not observed. In this context, it is interesting to note that the major genetic difference between CedPV and HeV or NiV lies within the coding strategy of the P gene, which is known to play an important role in evading the host innate immune system. Unlike HeV, NiV, and almost all known paramyxoviruses, the CedPV P gene lacks both RNA editing and also the coding capacity for the highly conserved V protein. Preliminary study indicated that CedPV infection of human cells induces a more robust IFN-β response than HeV. 相似文献
92.
Hannon RM Kelly SA Middleton KM Kolb EM Pomp D Garland T 《The Journal of heredity》2008,99(4):349-354
From outbred Hsd:ICR mice, we selectively bred 4 replicate lines for high running (High-Runner [HR] lines) on wheels while maintaining 4 nonselected lines as controls (C lines). An apparent Mendelian recessive, the "mini-muscle" (MM) allele, whose main phenotypic effect is to reduce hindlimb muscle mass by 50%, was discovered in 2 HR lines and 1 C line. This gene of major effect has gone to fixation in one selected line, remains polymorphic in another, and is now undetectable in the one C line. Homozygotes exhibit various pleiotropic effects, including a doubling of mass-specific muscle aerobic capacity, and larger hearts, livers, and spleens. To create a population suitable for mapping the genomic location of the MM allele and to better characterize its pleiotropic effects, we crossed females fixed for the MM allele with male C57BL/6J. F(1) males were then backcrossed to the MM parent females. Backcross (BC) mice (N = 404) were dissected, and a 50:50 ratio of normal to MM phenotype was observed with no overlap in relative muscle mass. In the BC, analysis of covariance revealed that MM individuals ran significantly more on days 5 and 6 of a 6-day exposure to running wheels (as in the routine selective-breeding protocol), were smaller in body mass, and had larger ventricles and spleens. 相似文献
93.
Qian Y Banerjee S Grossman CE Amidon W Nagy G Barcza M Niland B Karp DR Middleton FA Banki K Perl A 《The Biochemical journal》2008,415(1):123-134
TAL (transaldolase) was originally described in the yeast as an enzyme of the PPP (pentose phosphate pathway). However, certain organisms and mammalian tissues lack TAL, and the overall reason for its existence is unclear. Recently, deletion of Ser(171) (TALDeltaS171) was found in five patients causing inactivation, proteasome-mediated degradation and complete deficiency of TAL. In the present study, microarray and follow-up Western-blot, enzyme-activity and metabolic studies of TALDeltaS171 TD (TAL-deficient) lymphoblasts revealed co-ordinated changes in the expression of genes involved in the PPP, mitochondrial biogenesis, oxidative stress, and Ca(2+) fluxing. Sedoheptulose 7-phosphate was accumulated, whereas G6P (glucose 6-phosphate) was depleted, indicating a failure to recycle G6P for the oxidative branch of the PPP. Nucleotide analysis showed depletion of NADPH and NAD(+) and accumulation of ADP-ribose. TD cells have diminished Deltapsi(m) (mitochondrial transmembrane potential) and increased mitochondrial mass associated with increased production of nitric oxide and ATP. TAL deficiency resulted in enhanced spontaneous and H(2)O(2)-induced apoptosis. TD lymphoblasts showed increased expression of CD38, which hydrolyses NAD(+) into ADP-ribose, a trigger of Ca(2+) release from the endoplasmic reticulum that, in turn, facilitated CD20-induced apoptosis. By contrast, TD cells were resistant to CD95/Fas-induced apoptosis, owing to a dependence of caspase activity on redox-sensitive cysteine residues. Normalization of TAL activity by adeno-associated-virus-mediated gene transfer reversed the elevated CD38 expression, ATP and Ca(2+) levels, suppressed H(2)O(2)- and CD20-induced apoptosis and enhanced Fas-induced cell death. The present study identified the TAL deficiency as a modulator of mitochondrial homoeostasis, Ca(2+) fluxing and apoptosis. 相似文献
94.
Marie-José Gaillard Shinya Sugita M. Jane Bunting Richard Middleton Anna Broström Christopher Caseldine Thomas Giesecke Sophie E. V. Hellman Sheila Hicks Kari Hjelle Catherine Langdon Anne-Birgitte Nielsen Anneli Poska Henrik von Stedingk Sim Veski 《Vegetation History and Archaeobotany》2008,17(5):419-443
Information on past land cover in terms of absolute areas of different landscape units (forest, open land, pasture land, cultivated
land, etc.) at local to regional scales is needed to test hypotheses and answer questions related to climate change (e.g.
feedbacks effects of land-cover change), archaeological research, and nature conservancy (e.g. management strategy). The palaeoecological
technique best suited to achieve quantitative reconstruction of past vegetation is pollen analysis. A simulation approach
developed by Sugita (the computer model POLLSCAPE) which uses models based on the theory of pollen analysis is presented together
with examples of application. POLLSCAPE has been adopted as the central tool for POLLANDCAL (POLlen/LANdscape CALibration),
an international research network focusing on this topic. The theory behind models of the pollen–vegetation relationship and
POLLSCAPE is reviewed. The two model outputs which receive greatest attention in this paper are the relevant source area of
pollen (RSAP) and pollen loading in mires and lakes. Six examples of application of POLLSCAPE are presented, each of which
explores a possible use of the POLLANDCAL tools and a means of validating or evaluating the models with empirical data. The
landscape and vegetation factors influencing the size of the RSAP, the importance of pollen productivity estimates (PPEs)
for the model outputs, the detection of small and rare patches of plant taxa in pollen records, and quantitative reconstructions
of past vegetation and landscapes are discussed on the basis of these examples. The simulation approach is seen to be useful
both for exploring different vegetation/landscape scenarios and for refuting hypotheses. 相似文献
95.
Hughes TV Emanuel SL O'Grady HR Connolly PJ Rugg C Fuentes-Pesquera AR Karnachi P Alexander R Middleton SA 《Bioorganic & medicinal chemistry letters》2008,18(18):5130-5133
A novel series of 7-[1H-indol-2-yl]-2,3-dihydro-isoindol-1-ones designed to be inhibitors of VEGF-R2 kinase was synthesized and found to potently inhibit VEGF-R2 and Aurora-A kinases. The structure-based design, synthesis, and initial SAR of the series are discussed. 相似文献
96.
Xu G Searle LL Hughes TV Beck AK Connolly PJ Abad MC Neeper MP Struble GT Springer BA Emanuel SL Gruninger RH Pandey N Adams M Moreno-Mazza S Fuentes-Pesquera AR Middleton SA Greenberger LM 《Bioorganic & medicinal chemistry letters》2008,18(12):3495-3499
We herein disclose a novel series of 4-aminopyrimidine-5-carbaldehyde oximes that are potent and selective inhibitors of both EGFR and ErbB-2 tyrosine kinases, with IC(50) values in the nanomolar range. Structure-activity relationship (SAR) studies elucidated a critical role for the 4-amino and C-6 arylamino moieties. The X-ray co-crystal structure of EGFR with 37 was determined and validated our design rationale. 相似文献
97.
JK Sugden 《Biotechnic & histochemistry》2004,79(2):71-90
An overview of the basic principles of photochemistry is presented to facilitate discussion of fluorescence, quenching and quantum yields. These topics in turn provide the foundation for an account of fluorescence spectroscopy and its application to microscopy. A brief overview of light microscopy and the application of fluorescence microscopy is given. The influences of molecular features, such as aromatic character and substitution patterns, on color and fluorescence are described. The concept of color fading is considered with particular reference to its effect on microscopic preparations. A survey of representative fluorescent probes is provided, and their sensitivity, application, and limitations are described. The phototoxicity of fluorescent molecules is discussed using biomembranes and DNA as examples of targets of toxicity. Photodynamic therapy, a relatively new clinical application of phototoxicity, is described. Both anticancer and antimicrobial applications are noted, and an assessment is given of the current ideas on the ideal physicochemical properties of the sensitizing agents for such applications. 相似文献
98.
Angela M Patterson Caroline Schmutz Scott Davis Lucy Gardner Brian A Ashton Jim Middleton 《Arthritis research & therapy》2001,4(3):209
In chronic inflammatory foci, such as the rheumatoid joint, there is enhanced recruitment of phagocytes from the blood into the tissues. Chemokines are strongly implicated in directing the migration of these cells, although little is known regarding the chemokine receptors that could mediate their chemotaxis into the joint tissue. Therefore the objective of the study was to identify chemokine binding sites on macrophages and neutrophils within the rheumatoid synovium using radiolabeled ligand binding and in situ autoradiography. Specific binding sites for CCL3 (macrophage inflammatory protein-1α), CCL5 (RANTES), CCL2 (monocyte chemoattractant protein-1) and CXCL8 (IL-8) were demonstrated on CD68+ macrophages in the subintimal and intimal layers. The number and percentage of intimal cells that bound chemokines were greater in inflamed regions compared to noninflamed regions. The intensity of intimal binding varied between chemokines with the rank order, CCL3 > CCL5 > CCL2 > CXCL8. Neutrophils throughout the synovium bound CXCL8 but did not show any signal for binding CCL2, CCL3 or CCL5. 相似文献
99.
Plant collecting spread and densities: their potential impact on biogeographical studies in Thailand 总被引:2,自引:0,他引:2
J. A. N. Parnell D. A. Simpson J. Moat D. W. Kirkup P. Chantaranothai P. C. Boyce P. Bygrave S. Dransfield M. H. P. Jebb J. Macklin C. Meade D. J. Middleton A. M. Muasya A. Prajaksood C. A. Pendry R. Pooma S. Suddee P. Wilkin 《Journal of Biogeography》2003,30(2):193-209
Aims To produce representative aggregate maps of plant collection locations in Thailand and discuss their impact on biogeographical studies in Thailand and the surrounding region. Location Thailand. Methods A representative data set comprising 6593 plant specimen records for Thailand has been assembled. The data set contains ± all known collections for fifteen representative plant families and further records for another 104. All records are localized to Changwat (province), 6441 to at least quarter degree square. Results Analysis shows that the spread of collecting activity in Thailand is markedly uneven; 20% of collections come from a single Changwat (Chiang Mai) and 53% of Changwat have fifty or fewer collections. The distribution of collections by Changwat and by quarter degree square is erratic with most squares and Changwat having few collections, both in proportionate and absolute terms. Some of the most densely forested Changwats and squares appear undercollected. Distribution maps for common, easily recognized tree species in the genus Syzygium show distributional gaps. Conclusions Thailand is defined as an undercollected country. Even within the few well‐collected quarter degree squares the spread of collecting is still poor; almost all collections being localized to one of three mountain ranges or their foothills. There are many gaps in collecting activity which make impossible a straightforward interpretation of biogeographical pattern. It is argued that targeted collecting activity is needed, that assembly of this type of data set is therefore essential and that our data set and its interpretation is a model for all countries in the region. 相似文献