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901.
Background
Electron paramagnetic resonance (EPR) spectroscopy (also known as electron spin resonance, ESR, spectroscopy) is widely considered to be the “gold standard” for the detection and characterisation of radicals in biological systems.Scope of review
The article reviews the major positive and negative aspects of EPR spectroscopy and discusses how this technique and associated methodologies can be used to maximise useful information, and minimise artefacts, when used in biological studies. Consideration is given to the direct detection of radicals (at both ambient and low temperature), the use of spin trapping and spin scavenging (e.g. reaction with hydroxylamines), the detection of nitric oxide and the detection and quantification of some transition metal ions (particularly iron and copper) and their environment.Major conclusions
When used with care this technique can provide a wealth of valuable information on the presence of radicals and some transition metal ions in biological systems. It can provide definitive information on the identity of the species present and also information on their concentration, structure, mobility and interactions. It is however a technique that has major limitations and the user needs to understand the various pitfalls and shortcoming of the method to avoid making errors.General significance
EPR remains the most definitive method of identifying radicals in complex systems and is also a valuable method of examining radical kinetics, concentrations and structure. This article is part of a Special Issue entitled Current methods to study reactive oxygen species — pros and cons and biophysics of membrane proteins. Guest Editor: Christine Winterbourn. 相似文献902.
Cristina D. Castilhos Jamila MezzaliraMariana P.S. Goldim Vanessa V. DaitxCristina da S. Garcia Carla V. AndradeAna C. Breier Jaqueline CéAlexandre S. Mello Janice C. Coelho 《Gene》2014
This study aimed to determine the enzymatic activity in dried blood samples collected on filter paper (DBS) for the diagnosis of the following diseases: Fabry, Pompe, Mucopolysaccharidosis type I (MPS I) and Mucopolysaccharosis type VI (MPS VI). DBS was used for high risk patientscreening, according to clinical suspicion. Plasma, leukocytes and cultured fibroblasts were used to confirm the diagnosis when necessary. Among the 529 DBS samples sent to the laboratory, 164 had abnormal results. Confirmatory materials of 73 individuals were rerouted. The frequency of diagnosis for lysosomal storage disorders was 5.9%. DBS is an alternative screening technique used in high risk populations, which should lead to earlier diagnosis for lysosomal storage disorders (LSDs), help patients get treatment sooner and improve the outcome of the disease. 相似文献
903.
904.
905.
Tae-Joon Park Jeong-Hyun Kim Ho Jin Kim Joon Seol Bae Hyun Sub Cheong Byung Lae Park Hyoung Doo Shin 《Gene》2014
Multiple sclerosis (MS) and neuromyelitis optica (NMO) are demyelinating autoimmune inflammatory diseases that affect the central nervous system (CNS). Previous genome-wide or candidate gene studies have suggested that genetic variants might be associated with the risk of MS or NMO. Aquaporin 4 (AQP4) is a commonly distributed water channel in astrocytes of the CNS, and its expression is decreased in NMO lesions due to astrocyte cytotoxicity. Previous studies have suggested the associations of AQP4 single nucleotide polymorphisms (SNPs) with MS and/or NMO. However, there have been few replication studies in various ethnic populations. This study, as the first of its kind performed in an Asian population, investigated associations of AQP4 SNPs with the risk of inflammatory demyelinating disease (IDD), including MS and NMO, in a Korean population. A total of seven common AQP4 SNPs were selected based on status of linkage disequilibrium (LD), and then genotyped in 178 IDD cases (79 MS and 99 NMO patients) and 237 normal controls. Statistical analyses showed no significant associations between AQP4 SNPs/haplotypes and development of IDD, including MS and NMO (P > 0.05). Further replications in larger cohorts and other ethnic groups are needed. 相似文献
906.
907.
Dorothea Haas Hongying Gan-Schreier Claus-Dieter Langhans Alexandros Anninos Gisela Haege Peter Burgard Andreas Schulze Georg F. Hoffmann Jürgen G. Okun 《Gene》2014
Biochemical detection of inborn errors of creatine metabolism or transport relies on the analysis of three main metabolites in biological fluids: guanidinoacetate (GAA), creatine (CT) and creatinine (CTN). Unspecific clinical presentation of the diseases might be the cause that only few patients have been diagnosed so far. We describe a LC–MS/MS method allowing fast and reliable diagnosis by simultaneous quantification of GAA, CT and CTN in urine, plasma and cerebrospinal fluid (CSF) and established reference values for each material. 相似文献
908.
To evaluate the physiological importance of cytosolic ascorbate peroxidase (APX) in the reactive oxygen species (ROS)-scavenging system, a full-length cDNA clone, named LmAPX, encoding a cytosolic ascorbate peroxidase was isolated from Lycium chinense Mill. using homologous cloning, then the expression of LmAPX under salt stress was investigated. After sequencing and related analysis, the LmAPX cDNA sequence was 965 bp in length and had an open reading frame (ORF) of 750 bp coding for 250 amino acids. Furthermore, the LmAPX sequence was sub-cloned into prokaryotic expression vector pET28a and the recombinant proteins had a high expression level in Escherichia coli. Results from a southern blot analysis indicated that three inserts of this gene existed in the tobacco genome encoding LmAPX. Compared with the control plants (wild-type and empty vector control), the transgenic plants expressing the LmAPX gene exhibited lower amount of hydrogen peroxide (H2O2) and relatively higher values of ascorbate peroxidase activity, proline content, and net photosynthetic rate (Pn) under the same salt stress. These results suggested that overexpression of the LmAPX gene could decrease ROS production caused by salt stress and protect plants from oxidative stress. 相似文献
909.
Deepika Lodha Nisha Rathore Vinod Kataria N. S. Shekhawat 《Physiology and Molecular Biology of Plants》2014,20(3):375-383
Ephedra foliata Boiss. & Kotschy ex Boiss., (family – Ephedraceae), is an ecologically and economically important threatened Gymnosperm of the Indian Thar Desert. A method for micropropagation of E. foliata using nodal explant of mature female plant has been developed. Maximum bud-break (90 %) of the explant was obtained on MS medium supplemented with 1.5 mg l−1 of benzyl adenine (BA) + additives. Explant produces 5.3 ± 0.40 shoots from single node with 3.25 ± 0.29 cm length. The multiplication of shoots in culture was affected by salt composition of media, types and concentrations of plant growth regulators (PGR’s) and their interactions, time of transfer of the cultures. Maximum number of shoots (26.3 ± 0.82 per culture vessel) were regenerated on MS medium modified by reducing the concentration of nitrates to half supplemented with 200 mg l−1 ammonium sulphate {(NH4) 2SO4} (MMS3) + BA (0.25 mg l−1), Kinetin (Kin; 0.25 mg l−1), Indole-3-acetic acid (IAA; 0.1 mg l−1) and additives. The in vitro produced shoots rooted under ex vitro on soilrite moistened with one-fourth strength of MS macro salts in screw cap bottles by treating the shoot base (s) with 500 mg l−1 of Indole-3-butyric acid (IBA) for 5 min. The micropropagated plants were hardened in the green house. The described protocol can be applicable for (i) large scale plant production (ii) establishment of plants in natural habitat and (iii) germplasm conservation of this endemic Gymnosperm of arid regions. 相似文献
910.
Meiyao Wang Martin Misakian Hua-Jun He Peter Bajcsy Fatima Abbasi Jeffrey M Davis Kenneth D Cole Illarion V Turko Lili Wang 《Clinical proteomics》2014,11(1)