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21.
Lovell PJ Blaney FE Goodacre CJ Scott CM Smith PW Starr KR Thewlis KM Vong AK Ward SE Watson JM 《Bioorganic & medicinal chemistry letters》2007,17(4):1033-1036
Investigation of halogen substitution in lead compound 1 has led to the identification of analogues which combine high affinity for 5-HT(1A) receptors and potent serotonin reuptake inhibitory activity. Several compounds show an improved selectivity over 5-HT(1B) and 5-HT(1D) receptors and a superior pharmacokinetic profile in the rat. 相似文献
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Lloyd AJ William Allwood J Winder CL Dunn WB Heald JK Cristescu SM Sivakumaran A Harren FJ Mulema J Denby K Goodacre R Smith AR Mur LA 《The Plant journal : for cell and molecular biology》2011,67(5):852-868
In Arabidopsis, resistance to the necrotrophic fungus Botrytis cinerea is conferred by ethylene via poorly understood mechanisms. Metabolomic approaches compared the responses of the wild‐type, the ethylene‐insensitive mutant etr1‐1, which showed increased susceptibility, and the constitutively active ethylene mutants ctr1‐1 and eto2 both exhibited decreased susceptibility to B. cinerea. Fourier transform–infrared (FT‐IR) spectroscopy demonstrated reproducible biochemical differences between treatments and genotypes. To identify discriminatory mass‐to‐charge ratios (m/z) associated with resistance, discriminant function analysis was employed on spectra derived from direct injection electrospray ionisation‐mass spectrometry on the derived principal components of these data. Ethylene‐modulated m/z were mapped onto Arabidopsis biochemical pathways and many were associated with hydroxycinnamate and monolignol biosynthesis, both linked to cell wall modification. A high‐resolution linear triple quadrupole‐Orbitrap hybrid system confirmed the identity of key metabolites in these pathways. The contribution of these pathways to defence against B. cinerea was validated through the use of multiple Arabidopsis mutants. The FT‐IR microspectroscopy indicated that spatial accumulation of hydroxycinnamates and monolignols at the cell wall to confine disease was linked ot ethylene. These data demonstrate the power of metabolomic approaches in elucidating novel biological phenomena, especially when coupled to validation steps exploiting relevant mutant genotypes. 相似文献
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Dupuytren's disease (DD) is an ill-defined fibroproliferative disorder of the palm of the hands leading to digital contracture.
DD commonly occurs in individuals of northern European extraction. Cellular components and processes associated with DD pathogenesis
include altered gene and protein expression of cytokines, growth factors, adhesion molecules, and extracellular matrix components.
Histology has shown increased but varying levels of particular types of collagen, myofibroblasts and myoglobin proteins in
DD tissue. Free radicals and localised ischaemia have been suggested to trigger the proliferation of DD tissue. Although the
existing available biological information on DD may contain potentially valuable (though largely uninterpreted) information,
the precise aetiology of DD remains unknown. Systems biology combines mechanistic modelling with quantitative experimentation
in studies of networks and better understanding of the interaction of multiple components in disease processes. Adopting systems
biology may be the ideal approach for future research in order to improve understanding of complex diseases of multifactorial
origin. In this review, we propose that DD is a disease of several networks rather than of a single gene, and show that this
accounts for the experimental observations obtained to date from a variety of sources. We outline how DD may be investigated
more effectively by employing a systems biology approach that considers the disease network as a whole rather than focusing
on any specific single molecule. 相似文献
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Metabolite profiling of industrially important suspension-cultured mammalian cells is being increasingly used for rational improvement of bioprocesses. This requires the generation of global metabolite profiles that cover a broad range of metabolites and that are representative of the cells at the time of sampling. The protocol described here is a validated method for recovery of physiologically relevant amounts of key metabolites from suspension-cultured mammalian cells. The method is a two-step process consisting of initial quenching of the cells (to stop cellular metabolism and allow isolation of the cells) followed by extraction of the metabolites. The cells are quenched in 60% methanol supplemented with 0.85% (wt/vol) ammonium bicarbonate at -40 °C. Metabolites are then extracted from the quenched cells using two 100% methanol extractions followed by a single water extraction. Metabolite samples generated using this protocol are amenable to analysis by mass spectrometry-based techniques (e.g., gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry), NMR spectroscopy and enzymatic assays. 相似文献
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Parsons CE Young KS Parsons E Dean A Murray L Goodacre T Dalton L Stein A Kringelbach ML 《PloS one》2011,6(10):e25897
Cleft lip and palate is the most common of the congenital conditions affecting the face and cranial bones and is associated with a raised risk of difficulties in infant-caregiver interaction; the reasons for such difficulties are not fully understood. Here, we report two experiments designed to explore how adults respond to infant faces with and without cleft lip, using behavioural measures of attractiveness appraisal ('liking') and willingness to work to view or remove the images ('wanting'). We found that infants with cleft lip were rated as less attractive and were viewed for shorter durations than healthy infants, an effect that was particularly apparent where the cleft lip was severe. Women rated the infant faces as more attractive than men did, but there were no differences in men and women's viewing times of these faces. In a second experiment, we found that the presence of a cleft lip in domestic animals affected adults' 'liking' and 'wanting' responses in a comparable way to that seen for human infants. Adults' responses were also remarkably similar for images of infants and animals with cleft lip, although no gender difference in attractiveness ratings or viewing times emerged for animals. We suggest that the presence of a cleft lip can substantially change the way in which adults respond to human and animal faces. Furthermore, women may respond in different ways to men when asked to appraise infant attractiveness, despite the fact that men and women 'want' to view images of infants for similar durations. 相似文献
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Introduction: BK virus nephropathy is an emerging cause of renal transplant failure accounting for allograft loss in 45–50% of recipients between 2–60 months post‐transplantation. The Renal Transplant Unit in Royal Free Hospital has devised a local surveillance programme for screening renal transplant patients at weekly intervals by urinary cytology (UC) and electron microscopy (EM), and confirmation of positive results by plasma PCR and allograft biopsy. Objective: (i) To monitor the implementation of local guidelines; (ii) To compare UC with EM and (iii) To identify areas for improvement. Methods: Decoy cell and EM positive cases were retrieved from the WinPath database for new renal transplant recipients (n = 55) during 1st November 2004 to 31st October 2005 in Royal Free Hospital. Plasma PCR was retrieved for positive cases. Results: Up to eight samples were sent for UC at random intervals from 47 patients, and up to 7 were sent for EM from 42 patients. Eleven were UC‐positive and one was EM‐positive. PCR was not requested in UC‐positive cases and 3 out of 10 were positive retrospectively. The EM‐positive case was PCR‐positive but UC‐negative. Discussion: Urine Cytology is more appropriate and cost effective for screening than Electron Microscopy. During the period covered by this audit, samples were sent in an inconsistent fashion after allograft dysfunction rather than for screening. A screening protocol has been agreed and a re‐audit is planned. 相似文献