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51.
Purified chloroplast tRNAs were isolated fromPisum sativum leaves and radioactively labeled at their 3′ end using tRNA nucleotidyl transferase and α32P-labeled CTP. Pea ctDNA was fragmented using a number of restriction endonucleases and hybridized with thein vitro labeled chloroplast tRNAs by DNA transfer method. Genes for tRNAs have been found to be dispersed throughout the chloroplast
genome. A closer analysis of the several hybrid regions using recombinant DNA plasmids have shown that tRNA genes are localized
in the chloroplast genome in both single and multiple arrangements. Two dimensional gel electrophoresis of total ct tRNA have
identified 36 spots. All of them have been found to hybridize withPisum sativum ctDNA. Using recombinant clones, 30 of the tRNA spots have been mapped inPisum sativum ctDNA. 相似文献
52.
R.A. Bojar K.T. Holland J.P. Leeming W.J. Cunliffe 《Journal of applied microbiology》1988,64(6):497-504
In vitro tests using Staphylococcus epidermidis as a model have shown that at pH 5.6 the micro-organisms are sensitive to azelaic acid, whilst at pH 6.0 and 7.0 the cells become progressively resistant, especially with nutrients present. In a simple defined medium the growth rate was reduced at 1 mmol/l and growth inhibited at 25 mmol/l. The uptake of azelaic acid was pH dependant, higher transport at lower pH values, and required viable cells. Azelaic acid, 457 μmol/l gave 50% inhibition of protein synthesis and this mechanism could account for the bactericidal and bacteristatic effects. DNA and RNA were affected slightly by 100 mmol/l azelaic acid, and respiration by 500 mmol/l 相似文献
53.
Background
In recent years, several new hypotheses on phylogenetic relations among arthropods have been proposed on the basis of DNA sequences. One of the challenged hypotheses is the monophyly of hexapods. This discussion originated from analyses based on mitochondrial DNA datasets that, due to an unusual positioning of Collembola, suggested that the hexapod body plan evolved at least twice. Here, we re-evaluate the position of Collembola using ribosomal protein gene sequences. 相似文献54.
Leeming W 《Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences》2005,36(3):538-558
The aim of this paper is to understand how evolving ideas about heredity and genetics influenced new medical interests and practices and, eventually, the formation of 'medical genetics' as a medical specialism in Britain. I begin the paper by highlighting the social and institutional changes through which these ideas passed. I argue that, with time, there was a decisive convergence in thought that combined ideas about the familial aspects of heredity and the health needs of populations with an omnibus 'genetic' approach to health and illness that focused on the structures and activities of chromosomes and genes in individuals. I show how this convergence in thought was spurred on, first, by innovations in genetic science and technology in the years after 1960, and, second, by negotiated protocols and standards of medical practice worked out by bodies such as the relevant royal colleges, the linked associations and societies for medical professionals, affected training and research authorities, and the state. The notion of 'medical genetics' in Britain consequently gained a semblance of unanimity over its basic reference points and arrived at a meaning directly tributary to current acceptance of the term in the context of a medical specialism. 相似文献
55.
Rasmus H. Nielsen Reinout Stoop Diana J. Leeming Marina Stolina Per Qvist Claus Christiansen 《Biomarkers》2013,18(1):79-87
The objective of this work was to investigate whether collagen degradation products in protein extract from joints could provide quantitative information on cartilage damage. Osteoarthritis (OA) was surgically induced in rat knee joints. Joints were isolated 7, 14 and 28 days after surgery for protein extraction and histology. C-terminal telopeptide of type II collagen (CTX-II), CTX-I and hydroxyproline were measured in protein extracts. Matrix metalloproteinase (MMP)-2 and -9 activity was evaluated by gelatinase zymography and joint pathology was visualized by histology and immunohistochemistry. The results showed that levels of CTX-II were significantly increased in anterior cruciate ligament transection (ACLT)-operated compared with sham-operated knee joints on days 7 and 28, whereas the levels of hydroxyproline and CTX-I epitopes showed no difference. MMP activity was slightly increased in ACLT-operated joints. The CTX-II epitope was highly expressed and co-localized to damaged articular cartilage in ACLT-operated joints. We have therefore demonstrated an increased type II collagen degradation in knees after surgical induction of OA, and propose assessment of collagen degradation epitopes as a quantitative measure of cartilage damage. 相似文献
56.
Federica Genovese Morten A. Karsdal Diana J. Leeming Alexandra Scholze Martin Tepel 《PloS one》2014,9(10)
Objective
Cardiovascular diseases are among the most common causes of mortality in renal failure patients undergoing haemodialysis. A high turnover rate of the proteoglycan versican, represented by the increased presence of its fragmentation products in plasma, has previously been associated with cardiovascular diseases. The objective of the study was to investigate the association of versican turnover assessed in plasma with survival in haemodialysis patients.Methods
A specific matrix metalloproteinase-generated neo-epitope fragment of versican (VCANM) was measured in plasma of 364 haemodialysis patients with a 5-years follow-up, using a robust competitive enzyme-linked immunosorbent assays. Association between VCANM plasma concentration and survival was assessed by Kaplan-Meier analysis and adjusted Cox model.Results
Haemodialysis patients with plasma VCANM concentrations in the lowest quartile had increased risk of death (odds ratio, as compared to the highest quartile: 7.1, p<0.001), with a reduced survival of 152 days compared to 1295 days for patients with plasma VCANM in the highest quartile. Multivariate analysis showed that low VCANM (p<0.001) and older age (p<0.001) predicted death in haemodialysis patients.Conclusions
Low concentrations of the versican fragment VCANM in plasma were associated with higher risk of death among haemodialysis patients. A possible protective role for the examined versican fragment is suggested. 相似文献57.
Hashem?A?Shihab Julian?Gough Matthew?Mort David?N?Cooper Ian?NM?Day Tom?R?GauntEmail author 《Human genomics》2014,8(1):11
As the number of non-synonymous single nucleotide polymorphisms (nsSNPs) identified through whole-exome/whole-genome sequencing programs increases, researchers and clinicians are becoming increasingly reliant upon computational prediction algorithms designed to prioritize potential functional variants for further study. A large proportion of existing prediction algorithms are ‘disease agnostic’ but are nevertheless quite capable of predicting when a mutation is likely to be deleterious. However, most clinical and research applications of these algorithms relate to specific diseases and would therefore benefit from an approach that discriminates between functional variants specifically related to that disease from those which are not. In a whole-exome/whole-genome sequencing context, such an approach could substantially reduce the number of false positive candidate mutations. Here, we test this postulate by incorporating a disease-specific weighting scheme into the Functional Analysis through Hidden Markov Models (FATHMM) algorithm. When compared to traditional prediction algorithms, we observed an overall reduction in the number of false positives identified using a disease-specific approach to functional prediction across 17 distinct disease concepts/categories. Our results illustrate the potential benefits of making disease-specific predictions when prioritizing candidate variants in relation to specific diseases. A web-based implementation of our algorithm is available at http://fathmm.biocompute.org.uk. 相似文献
58.
59.
R A Bojar K T Holland J P Leeming W J Cunliffe 《The Journal of applied bacteriology》1988,64(6):497-504
In vitro tests using Staphylococcus epidermidis as a model have shown that at pH 5.6 the micro-organisms are sensitive to azelaic acid, whilst at pH 6.0 and 7.0 the cells become progressively resistant, especially with nutrients present. In a simple defined medium the growth rate was reduced at 1 mmol/l and growth inhibited at 25 mmol/l. The uptake of azelaic acid was pH dependent, higher transport at lower pH values, and required viable cells. Azelaic acid, 457 mumol/l gave 50% inhibition of protein synthesis and this mechanism could account for the bactericidal and bacteristatic effects. DNA and RNA were affected slightly by 100 mmol/l azelaic acid, and respiration by 500 mmol/l. 相似文献
60.
D.J. Leeming N. Willumsen J.M.B. Sand S. Holm Nielsen B. Dasgupta C. Brodmerkel M. Curran C.L. Bager MA. Karsdal 《Biochemistry and Biophysics Reports》2019
ObjectivesLysyl oxidase like 2 (LOXL2) is associated with poor prognosis in idiopathic pulmonary disease (IPF) and cancer. We developed an Enzyme-linked immunosorbent assay (ELISA) targeting the LOXL2 neo-epitope generated through the release of the signal peptide during LOXL2 maturation.Design and methodsAn ELISA targeting the N-terminal site of the human LOXL2 was developed including technical optimization and validation steps. Serum LOXL2 was measured in patients with breast, colorectal, lung, ovarian, pancreatic and prostate cancer, melanoma, IPF and in healthy controls (n = 16).ResultsA technically robust and specific assay was developed. LOXL2 was detectable in serum from healthy controls and showed reactivity towards recombinant LOXL2. Compared to controls, LOXL2 levels were significantly (p < 0.001–0.05) elevated in serum from patients with breast, colerectal, lung, ovarian and pancreatic cancer (mean range: 49–84 ng/mL), but not in prostate cancer (mean: 36 ng/mL) and malignant melanoma patients (41 ng/mL). Serum LOXL2 was elevated in IPF patients compared to healthy controls (mean: 76.5 vs 46.8 ng/mL; p > 0.001)ConclusionsA specific ELISA towards the N-terminal neo-epitope site in LOXL2 was developed which detected significantly elevated serum levels from patients with above-mentioned cancer types or IPF compared to healthy controls. 相似文献