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71.
Kozic D Medic-Stojanoska M Ostojic J Popovic L Vuckovic N 《Neuro endocrinology letters》2007,28(5):560-564
MR spectroscopy (MRS) of hormonally active pituitary adenomas has not been published in literature. We report MR imaging and spectroscopy findings in a 41-year-old man with extrapituitary growth hormone-secreting adenoma. Application of the single voxel proton MRS, SE 135 technique, with voxel size 11x11x11 mm, revealed the elevated choline peak (resonance at 3.2 ppm) in the paramedial aspect of the tumor, while no metabolic activity in the mentioned region was noted using the same method 11 months after Lanreotide treatment. Elevation of choline peak in functional pituitary adenomas could represent an active marker of cellular proliferation, compatible with increased hormonal activity. 相似文献
72.
Matthew-Wood syndrome is caused by truncating mutations in the retinol-binding protein receptor gene STRA6 总被引:3,自引:0,他引:3
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73.
Lozo J Jovcic B Kojic M Dalgalarrondo M Chobert JM Haertlé T Topisirovic L 《Current microbiology》2007,55(3):266-271
Screening the collection of natural isolates from semi-hard homemade cheese resulted in isolation and characterization of
strain Lactobacillus paracasei subsp. paracasei BGSJ2-8. The strain BGSJ2-8 harbors several important phenotypes, such as bacteriocin production, aggregation phenomenon,
and production of proteinase. Bacteriocin SJ was purified by three-step chromatography. Mass spectrometry established molecular
mass of the active peptide at 5372 Da. The auto-aggregation phenotype of wild-type (WT) strain was mediated by secreted aggregation-promoting
factor (protein of molecular mass > 200 kDa), probably acting in cooperation with other cell surface protein(s). Comparative
study of WT and its spontaneous nonaggregating derivative revealed that aggregation factor was responsible for the observed
differences in the bacteriocin and proteinase activities. Bacteriocin SJ activity and resistance to different stresses were
higher in the presence of aggregating factor. In contrast, proteinase activity was stronger in the nonaggregating derivative. 相似文献
74.
Fluorescent fructose derivatives for imaging breast cancer cells 总被引:1,自引:0,他引:1
Levi J Cheng Z Gheysens O Patel M Chan CT Wang Y Namavari M Gambhir SS 《Bioconjugate chemistry》2007,18(3):628-634
Breast cancer cells are known to overexpress Glut5, a sugar transporter responsible for the transfer of fructose across the cell membrane. Since Glut5 transporter is not significantly expressed in normal breast cells, fructose uptake can potentially be used to differentiate between normal and cancerous cells. Fructose was labeled with two fluorophores at the C-1 position: 7-nitro-1,2,3-benzadiazole (NBD) and Cy5.5. The labeling site was chosen on the basis of the presence and substrate specificity of the key proteins involved in the first steps of fructose metabolism. Using fluorescence microscopy, the uptake of the probes was studied in three breast cancer cell lines: MCF 7, MDA-MB-435, and MDA-MB-231. Both fluorescent fructose derivatives showed a very good uptake in all tested cell lines. The level of uptake was comparable to that of the corresponding glucose analogs, 2-NBDG and Cy5.5-DG. Significant uptake of 1-NBDF derivative was not observed in cells lacking Glut5 transporter, while the uptake of the 1-Cy5.5-DF derivative was independent of the presence of a fructose-specific transporter. While 1-NBDF showed Glut5-specific accumulation, the coupling of a large fluorophore such as Cy5.5 likely introduces big structural and electronic changes, leading to a fructose derivative that does not accurately describe the uptake of fructose in cells. 相似文献
75.
Stankovic S Soldo B Beric-Bjedov T Knezevic-Vukcevic J Simic D Lazarevic V 《Systematic and applied microbiology》2007,30(1):8-15
A collection of 212 gram-positive bacilli isolated from natural habitats was screened for the presence of intervening sequences (introns and intein-coding sequences) in the SPbeta prophage-related ribonucleotide reductase genes bnrdE and bnrdF. Three novel configurations were identified on the basis of the presence of (i) intervening sequences in bnrdE and bnrdF, and (ii) an ORF in the bnrdE-bnrdF spacer. Analysis of the cell wall genetic determinants as well as of the incorporation of radio-labelled glycerol into cell wall allowed newly and previously identified B. subtilis strains with different configurations of bnrdE/bnrdF intervening sequences to be assigned to one of two subspecies. Strains apparently belonging to the subsp. subtilis contain three intervening sequences many of which are associated with the putative homing endonuclease activity. Strains of the subsp. spizizenii contain only one or two ORF-less group I introns. Introns occupying bnrdF are confined to the subspecies subtilis. 相似文献
76.
BelAiba RS Djordjevic T Petry A Diemer K Bonello S Banfi B Hess J Pogrebniak A Bickel C Görlach A 《Free radical biology & medicine》2007,42(4):446-459
NADPH oxidases have been identified as sources of reactive oxygen species (ROS) in vascular cells. In addition to the initially described enzyme containing gp91phox (NOX2), several homologues to NOX2 have been identified. Whereas NOX1, NOX2, and NOX4 are expressed in endothelial cells, a functional role of NOX5 containing additional N-terminal calcium-binding domains of varying sequences has not been reported in these cells. NOX5 protein was found in the endoplasmic reticulum of human microvascular endothelial cells (HMEC-1) and in the vascular wall. HMEC-1 cells expressed NOX5beta and NOX5delta as well as a variant lacking calcium-binding domains (NOX5S). NOX5beta and NOX5S increased basal ROS levels. Ionomycin exclusively enhanced NOX5beta-mediated ROS production. Although p22phox, when overexpressed, interacted with both NOX5 proteins, it was not essential for NOX5-mediated ROS production. NOX5 proteins stimulated endothelial cell proliferation and the formation of capillary-like structures whereas depletion of NOX5 by siRNA prevented these responses to thrombin. These data show that endothelial cells express different NOX5 variants including NOX5S lacking calcium-binding domains. NOX5 proteins are functional, promoting endothelial ROS production, proliferation, and the formation of capillary-like structures and contribute to the endothelial response to thrombin. These findings suggest that NOX5 variants play a novel role in controlling ROS-dependent processes in the vasculature. 相似文献
77.
Performance analysis of MPI collective operations 总被引:1,自引:0,他引:1
Jelena Pješivac-Grbović Thara Angskun George Bosilca Graham E. Fagg Edgar Gabriel Jack J. Dongarra 《Cluster computing》2007,10(2):127-143
Previous studies of application usage show that the performance of collective communications are critical for high-performance
computing. Despite active research in the field, both general and feasible solution to the optimization of collective communication
problem is still missing.
In this paper, we analyze and attempt to improve intra-cluster collective communication in the context of the widely deployed
MPI programming paradigm by extending accepted models of point-to-point communication, such as Hockney, LogP/LogGP, and PLogP,
to collective operations. We compare the predictions from models against the experimentally gathered data and using these
results, construct optimal decision function for broadcast collective. We quantitatively compare the quality of the model-based
decision functions to the experimentally-optimal one. Additionally, in this work, we also introduce a new form of an optimized
tree-based broadcast algorithm, splitted-binary.
Our results show that all of the models can provide useful insights into various aspects of the different algorithms as well
as their relative performance. Still, based on our findings, we believe that the complete reliance on models would not yield
optimal results. In addition, our experimental results have identified the gap parameter as being the most critical for accurate
modeling of both the classical point-to-point-based pipeline and our extensions to fan-out topologies.
相似文献
Jack J. DongarraEmail: |
78.
Djordjevic MA Oakes M Li DX Hwang CH Hocart CH Gresshoff PM 《Journal of proteome research》2007,6(9):3771-3779
Molecular signaling interactions in the plant apoplast are important for defense and developmental responses. We examined the soybean proteome of the apoplastic conduit of root-to-shoot communication, the xylem stream, using gel electrophoresis combined with two types of tandem mass spectrometry. We examined soybeans for the presence of a Bradyrhizobium japonicum-induced, long distance developmental signal that controls autoregulation of nodulation (AON) to determine if xylem proteins (XPs) were involved directly or indirectly in AON. The xylem and apoplast fluids collected in hypocotyl, epicotyl, and stem tissue contained a highly similar set of secreted proteins. The XPs were different from those secreted from imbibing seed implying they play important basic roles in xylem function. The XPs of wild-type and nts1007 plants were indistinguishable irrespective of plant age, inoculation status, or time after inoculation suggesting that none was directly involved in AON. XPs were continuously loaded into the xylem stream, as they were present even 28 h after shoot decapitation. These results were consistent with semiquantitative RT-PCR studies that examined the expression of genes corresponding to the XPs under inoculated or uninoculated conditions. Monitoring the expression of XP genes by RT-PCR showed that four possessed root biased expression. This suggested that the corresponding protein products could be produced in roots and travel long distances to shoots. Of these, a species of lipid transfer protein is a candidate for a water-soluble, long-distance signal-carrier due to the presence of hydrophobic clefts that bind known plant signals in vitro. Two soybean XPs identified in this study, lipid transfer protein and Kunitz trypsin inhibitor (KTI), have known roles in plant signaling. 相似文献
79.
Radović Jelena Suručić Relja Niketić Marjan Kundaković-Vasović Tatjana 《Molecular and cellular biochemistry》2022,477(7):1893-1903
Molecular and Cellular Biochemistry - Alchemilla viridiflora Rothm., Rosaceae is a herbaceous plant widespread in central Greece, Bulgaria, North Macedonia and Serbia with Kosovo. Liquid... 相似文献
80.
Ivanovic Nevena Dj Radosavljevic Branimir Zekovic Milica Korcok Davor Ignjatovic Svetlana Djordjevic Brizita Milinkovic Neda 《Biometals》2022,35(2):267-283
BioMetals - This study aimed to investigate the short-term effects of three magnesium (Mg) dietary supplements containing mineral immediately available for absorption on Mg biochemical status... 相似文献