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161.
162.
We describe a simple method for locating tryptophanyl-tRNA synthetase (E.C. 6.1.1.2) on cellulose acetate gels (Cellogel) following electrophoresis. Employing electrophoretic conditions which result in the separation of mouse and human tryptophanyl-tRNA synthetases, we have analyzed extracts of a number of independently derived mouse-human somatic cell hybrids and subclones derived from these hybrids for the presence of human tryptophanyl-tRNA synthetase. Electrophoretic patterns of hybrid extracts which contain human tryptophanyl-tRNA synthetase exhibit three bands. This is consistent with published evidence that the enzyme from mammalian cells is a homologous dimer. The electrophoretic patterns derived from some hybrids are unusual in that the human and hybrid bands of activity are more intense than the mouse band from the same hybrid. An analysis of hybrid cells and extracts indicates that human tryptophanyl-tRNA synthetase segregates with human chromosome 14 and with the only enzyme marker which has previously been assigned to this chromosome, nucleoside phosphorylase.R. M. D. was supported by a postdoctoral fellowship from the Damon Runyon Fund for Cancer Research. The work described was supported in part by grants from Cancer Research Campaign, the Medical Research Council, and NATO. 相似文献
163.
Ian M. Morrison 《Phytochemistry》1974,13(7):1161-1165
Lignin-carbohydrate and lignin-hemicellulose complexes were extracted sequentially from four varieties of Lolium perenne which had previously been 相似文献
164.
Electron paramagnetic resonance using site‐directed spin labeling can be used as an approach for determination of protein structures that are difficult to solve by other methods. One important aspect of this approach is the measurement of interlabel distances using the double electron–electron resonance (DEER) method. Interpretation of experimental data could be facilitated by a computational approach to calculation of interlabel distances. We describe an algorithm, PRONOX, for rapid computation of interlabel distances based on calculation of spin label conformer distributions at any site of a protein. The program incorporates features of the label distribution established experimentally, including weighting of favorable conformers of the label. Distances calculated by PRONOX were compared with new DEER distances for amphiphysin and annexin B12 and with published data for FCHo2 (F‐BAR), endophilin, and α‐synuclein, a total of 44 interlabel distances. The program reproduced these distances accurately (r2 = 0.94, slope = 0.98). For 9 of the 11 distances for amphiphysin, PRONOX reproduced the experimental data to within 2.5 Å. The speed and accuracy of PRONOX suggest that the algorithm can be used for fitting to DEER data for determination of protein tertiary structure. © 2011 Wiley Periodicals, Inc. Biopolymers 97: 35–44, 2012. 相似文献
165.
Chromosoma - The high-order structure of metaphase chromosomes remains still under investigation, especially the 30-nm structure that is still controversial. Advanced 3D imaging has provided useful... 相似文献
166.
Edmund Ziomek Neil Kirkpatrick Ian D. Reid 《Applied microbiology and biotechnology》1991,35(5):669-673
Summary Improving the availability of oxygen by adding polydimethylsiloxanes (PDMS) oxygen carriers to Trametes versicolor cultures increased pulp brightening. The presence of the oxygen carriers in cultures of T. versicolor with hardwood kraft pulp increased the growth rate of the fungus, but not the ultimate biomass yield. The PDMS also stimulated brightening of hardwood kraft pulp by it T. versicolor immobilized in polyurethane foam. A threefold increase in the oxygen uptake rate in T. versicolor cultures with PDMS was observed. This increase can be explained by elevated oxygen transfer rate and attributed to the surfactant properties of PDMS.
Offprint requests to: E. ZiomekIssued as NRCC 32760 相似文献
167.
168.
Houtman R Krijgsveld J Kool M Romijn EP Redegeld FA Nijkamp FP Heck AJ Humphery-Smith I 《Proteomics》2003,3(10):2008-2018
A mouse model for nonatopic asthma was employed to study the alterations of the lung proteome to gain insight into the underlying molecular mechanisms of disease pathophysiology post-challenge. Lung samples from asthmatic and control mice were used to generate 24 high quality two-dimensional electrophoresis gels wherein 2115 proteins were examined for disease relevance. In total, 23 proteins were significantly up- or down-regulated following hapten-challenge of dinitro-fluorobenzene-hypersensitive mice. Twenty proteins were identified by mass spectrometry, of which 18 could be linked to asthma related symptoms, such as stress and inflammation, lung detoxification, plasma exudation and/or tissue remodeling. As such, proteomics was clearly vindicated as a means of studying this complex disease phenomenon. The proteins found in this study may not necessarily play a role in the immunological mechanisms and/or pathophysiology of asthma development. However, they may prove useful as surrogate biomarkers for quantitatively monitoring disease state progression or response to therapy. The mathematics of achieving statistical confidence from low numbers of gel replicates containing large numbers of independent variables stress the need for high numbers of replicates to better sample the population of proteins revealed by two-dimensional gel electrophoresis. 相似文献
169.
Lizabeth Rosenbaum M. Houman Fekrazad Ian Rabinowitz Mohammad A. Vasef 《Journal of Hematopathology》2009,2(2):127-131
We report two rare examples of Epstein–Barr virus (EBV)-associated inflammatory pseudotumor of the spleen. One patient presented with night sweats, abdominal pain, and weight loss and was found to have a splenic mass on CT scan suspected of lymphoma. The splenic mass in second patient was found incidentally at the time of work up for kidney stones. The pathologic examination of these splenectomy specimens showed similar histologic features. However, the spindle cells were composed of EBV-infected follicular dendritic cells in one case whereas the second case lacked significant follicular dendritic cell proliferation and showed only focal EBV-infected cells suggesting that these proliferations are heterogenous in nature. 相似文献
170.
John V. Pappachan Tim G. Coulson Nicholas J. A. Child David J. Markham Sarah M. Nour Mark C. K. Pulletz Matthew J. Rose-Zerilli Kim de Courcey-Golder Sheila J. Barton Ian A. Yang John W. Holloway 《Immunogenetics》2009,61(10):657-662
The systemic inflammatory response syndrome (SIRS) is associated with activation of innate immunity. We studied the association between mortality and measures of disease severity in the intensive care unit (ICU) and functional polymorphisms in genes coding for Toll-like receptor 4 (TLR4), macrophage migratory inhibitory factor (MIF), tumour necrosis factor (TNF) and lymphotoxin-alpha (LTA). Two hundred thirty-three patients with severe SIRS were recruited from one general adult ICU in a tertiary centre in the UK. DNA from patients underwent genotyping by 5′ nuclease assay. Genotype was compared to phenotype. Primary outcome was mortality in ICU. Minor allele frequencies were TLR4 +896G 7%, MIF 173C 16%, TNF ?238A 10% and LTA +252G 34%. The frequency of the hypoimmune minor allele TNF ?238A was significantly higher in patients who died in ICU compared to those who survived (p?=?0.0063) as was the frequency of the two haplotypes LTA +252G, TNF ?1031T, TNF ?308G, TNF ?238A and LTA +252G, TNF?1031T, TNF?308A and TNF?238A (p?=?0.0120 and 0.0098, respectively). These findings re-enforce the view that a balanced inflammatory/anti-inflammatory response is the most important determinant of outcome in sepsis. Genotypes that either favour inflammation or its counter-regulatory anti-inflammatory response are likely to influence mortality and morbidity. 相似文献