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21.
Główka FK Łada MK Grund G Wachowiak J 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,850(1-2):569-574
A direct and selective HPLC method with refractometric detection was worked out for determination of treosulfan in plasma and urine of children. Before injection onto reverse phase column plasma samples with treosulfan and barbital (I.S.) were clarified using filtration. The mobile phase was composed of phosphate buffer, pH 5 and acetonitrile. The linear range of the standard curve of treosulfan spanned concentrations of 10.0-2000.0 microg/ml and 50.0-10000.0 microg/ml in plasma and urine, respectively, and covered the levels found in biological fluids after infusion of the drug. The limit of detection amounted to 5 microg/ml for plasma and 25 microg/ml for urine. Intra- and inter-day precision and accuracy of the measurement fulfilled analytical criteria accepted in pharmacokinetic studies. Recovery of treosulfan as well as stability in biological fluids was also calculated. The validated method was successfully applied in pharmacokinetic studies of treosulfan administered to children prior to haematopoietic stem cell transplantation. Differences between pharmacokinetics of treosulfan in children and adults were also studied. 相似文献
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Marzec-Wróblewska Urszula Kamiński Piotr Łakota Paweł Szymański Marek Wasilow Karolina Ludwikowski Grzegorz Jerzak Leszek Stuczyński Tomasz Woźniak Alina Buciński Adam 《Biological trace element research》2019,188(2):251-260
Biological Trace Element Research - We analyzed cobalt (Co), chromium (Cr), and lead (Pb) concentrations in human semen and catalase CAT activity in seminal plasma and the effects of their... 相似文献
24.
David Fulton Jason Fontana Grzegorz Sowa Jean-Philippe Gratton Michelle Lin Kai-Xun Li Belinda Michell Bruce E Kemp David Rodman William C Sessa 《The Journal of biological chemistry》2002,277(6):4277-4284
The subcellular localization of endothelial nitric-oxide synthase (eNOS) is critical for optimal coupling of extracellular stimulation to nitric oxide production. Because eNOS is activated by Akt-dependent phosphorylation to produce nitric oxide (NO), we determined the subcellular distribution of eNOS phosphorylated on serine 1179 using a variety of methodologies. Based on sucrose gradient fractionation, phosphorylated-eNOS (P-eNOS) was found in both caveolin-1-enriched membranes and intracellular domains. Co-transfection of eNOS with Akt and stimulation of endothelial cells with vascular endothelial growth factor (VEGF) increased the ratio of P-eNOS to total eNOS but did not change the relative intracellular distribution between these domains. The proper localization of eNOS to intracellular membranes was required for agonist-dependent phosphorylation on serine 1179, since VEGF did not increase eNOS phosphorylation in cells transfected with a non-acylated, mistargeted form of eNOS. Confocal imaging of P-eNOS and total eNOS pools demonstrated co-localization in the Golgi region and plasmalemma of transfected cells and native endothelial cells. Finally, VEGF stimulated a large increase in NO localized in both the perinuclear region and the plasma membrane of endothelial cells. Thus, activated, phosphorylated eNOS resides in two cellular compartments and both pools are VEGF-regulated to produce NO. 相似文献
25.
Daniele Arosio Herman E Kwansa Henry Gering Grzegorz Piszczek Enrico Bucci 《Biopolymers》2002,63(1):1-11
We used static and dynamic light scattering for comparing the mass (MW) and hydrodynamic radius (R(h)) of several hemoglobin systems, namely human hemoglobin, bovine hemoglobin, human hemoglobin cross-linked with a sebacyl residue, and bovine hemoglobin cross-linked with an adipoyl residue. We measured the MW and R(h) of these systems in 0.1M phosphate buffer at pH 7.0 in the absence and in the presence of either betaine or glycerol up to 1.7 molal concentrations. The 90 degrees scattering was measured with a photon counting machine equipped with a diode laser at 783 nm. The Rayleigh ratio [R(theta)] of the instrument was estimated using R(theta) = 7.19E-6 cm(-1) for toluene at 783 nm. The refractive index increment of hemoglobin solutions was measured using a laser beam at 750 nm. We estimated a value dn/dc = 0.210 cm3/g in the absence and dn/dc = 0.170 in the presence of 1.7 molal osmolites. For all systems both in liganded and unliganded form, the static light scattering data showed a 16% mass increase with increasing concentration of osmolites. The hydrodynamic radii of all investigated systems in the presence and absence of osmolites were close to 3.17 nm. Assuming a partial specific volume nu = 0.739 for hemoglobin, and using spherical geometry, the estimated average hydration volume of hemoglobin was 32.6 L/mole in the absence of osmolites. It decreased to 23.5 L/mole in the presence of 1.7 molal osmolites. Assuming that the density of water in the hydration volume is D = 1.0 g/cm3, the hydration of Hb was 0.51 gH2O/gHb, with a surface density of 0.20 molH2O/A2. The hydration decreased to 0.33 gH2O/gHb and 0.14 molH2O/A2 in the presence of 1.7 molal osmolites. The decreased hydration was compensated by the increased mass (i.e., decreased surface area per unit volume) so that the thickness of the water shell around these proteins remained close to a single layer of water molecules. These findings indicate that the combination of static and dynamic light scattering offer unique means for investigating the relevance of water activity on the structure and function of biological macromolecules. In the case of hemoglobin, the data suggest that the decreased oxygen affinity in the presence of osmolites reported by Colombo et al. (M. F. Colombo, D. C. Rau, and V. A. Parsegian Science, 1992, Vol. 256, pp. 655-659), as due to ligand linked water binding on hemoglobin surface, is part of a complex phenomenon involving the hydration shell of hemoglobin and the formation of low affinity supertetrameric molecules. 相似文献
26.
Crystal structures of two homologous pathogenesis-related proteins from yellow lupine 总被引:4,自引:0,他引:4
Pathogenesis-related class 10 (PR10) proteins are restricted to the plant kingdom where they are coded by multigene families and occur at high levels. In spite of their abundance, their physiological role is obscure although members of a distantly related subclass (cytokinin-specific binding proteins) are known to bind plant hormones. PR10 proteins are of special significance in legume plants where their expression patterns are related to infection by the symbiotic, nitrogen-fixing bacteria. Here we present the first crystal structures of classic PR10 proteins representing two homologues from one subclass in yellow lupine. The general fold is similar and, as in a birch pollen allergen, consists of a seven-stranded beta-sheet wrapped around a long C-terminal helix. The mouth of a large pocket formed between the beta-sheet and the helix seems a likely site for ligand binding. The shape of the pocket varies because, in variance with the rigid beta-sheet, the helix shows unusual conformational variability consisting in bending, disorder, and axial shifting. A surface loop, proximal to the entrance to the internal cavity, shows an unusual structural conservation and rigidity in contrast to the high glycine content in its sequence. The loop is different from the so-called glycine-rich P-loops that bind phosphate groups of nucleotides, but it is very likely that it does play a role in ligand binding in PR10 proteins. 相似文献
27.
Subspecific relationships of the European beaverCastor fiber have been obscured by failure to follow the rules of the International Code of Zoological Nomenclature and remain an open
issue. Inconsequence in the use of subspecies names caused a nomenclatural as well as a taxonomic confusion. We discuss these
controversial and incorrect nomenclatural decisions, and recognize 9 nominal subspecies of European beaver, bearing 9 available
names:C. f. fiber Linnaeus, 1758,C. f. galliae Geoffroy, 1803, C. f. albicus Matschie, 1907,C. f. vistulanus Matschie, 1907,C. f. pohlei Serebrennikov, 1929,C. f. birulai Serebrennikov, 1929,C. f. tuvinicus Lavrov, 1969,C. f. belorussicus Lavrov, 1981, andC. f. orientoeuropaeus Lavrov, 1981. 相似文献
28.
Although plasmid DNA vectors have been extensively applied in biotechnology, there is still a lack of standard plasmid vector classification. Here, we propose a classification method for commonly used plasmid vectors. Plasmid vectors were classified into different classes based on their replication origin, selection marker and promoter information. The replication origins of plasmid vectors were classified as: prokaryotic replication origin, eukaryotic replication origin and viral replication origin. Selection markers of plasmid vectors were mainly classified as ampicillin, kanamycin, neomycin, chloramphenicol, gentamycin, tetracycline, erythromycin, streptomycin, vancomycin and spectinomycin resistance gene markers. Promoter sequences were also classified as prokaryotic, eukaryotic and viral promoters. Finally, the nomenclature of common plasmid vectors has three determinants. We believe that the classification of plasmid vectors can provide useful information for researchers employing molecular cloning procedures. A web service of the plasmid classification was established and it is available from http://www.computationalmedicalbiology.org/plasclas.aspx. 相似文献
29.
Vanden Wymelenberg A Minges P Sabat G Martinez D Aerts A Salamov A Grigoriev I Shapiro H Putnam N Belinky P Dosoretz C Gaskell J Kersten P Cullen D 《Fungal genetics and biology : FG & B》2006,43(5):343-356
The white-rot basidiomycete Phanerochaete chrysosporium employs extracellular enzymes to completely degrade the major polymers of wood: cellulose, hemicellulose, and lignin. Analysis of a total of 10,048 v2.1 gene models predicts 769 secreted proteins, a substantial increase over the 268 models identified in the earlier database (v1.0). Within the v2.1 'computational secretome,' 43% showed no significant similarity to known proteins, but were structurally related to other hypothetical protein sequences. In contrast, 53% showed significant similarity to known protein sequences including 87 models assigned to 33 glycoside hydrolase families and 52 sequences distributed among 13 peptidase families. When grown under standard ligninolytic conditions, peptides corresponding to 11 peptidase genes were identified in culture filtrates by mass spectrometry (LS-MS/MS). Five peptidases were members of a large family of aspartyl proteases, many of which were localized to gene clusters. Consistent with a role in dephosphorylation of lignin peroxidase, a mannose-6-phosphatase (M6Pase) was also identified in carbon-starved cultures. Beyond proteases and M6Pase, 28 specific gene products were identified including several representatives of gene families. These included 4 lignin peroxidases, 3 lipases, 2 carboxylesterases, and 8 glycosyl hydrolases. The results underscore the rich genetic diversity and complexity of P. chrysosporium's extracellular enzyme systems. 相似文献
30.
Hendrik Klein Grzegorz Niedźwiedzki Sebastian Voigt Abdelouahed Lagnaoui Abdelkbir Hminna Hafid Saber 《Ichnos》2013,20(1):24-30
Early Triassic chirotherian footprint assemblages from Poland, Germany, and Morocco are important for understanding archosaur evolution in the aftermath of the Permian-Triassic crisis. However, their ichnotaxonomy is confusing because various authors have interpreted their diversity differently. After an analysis and ichnotaxonomic re-assessment, the presence of the ichnogenera Brachychirotherium, Isochirotherium, and Chirotherium in these assemblages is not supported. Distant similarities with these ichnotaxa are functions of extra morphological variation and substrate-related factors. Instead, Early Triassic chirotherian footprints described under these names are assigned here to the ichnogenus Protochirotherium and to a more slender morphotype identified as Synaptichnium. In particular, Protochirotherium appears to be more widely distributed in central Pangea as a characteristic morphotype reflecting a distinct stage in archosaur evolution. Trackmakers were nonarchosaurian archosauriforms or, alternatively, stem-group crocodylians. Morphologically and temporally these footprints match the hypothetical ancestor of the Chirotherium barthii trackmaker. Chirotherium barthii appears by the beginning of the Middle Triassic. Because of its restricted stratigraphic range, and its wider distribution in central Pangea, Protochirotherium also has biostratigraphic significance for this region and can be considered as an indicator of Early Triassic-aged strata. 相似文献