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151.
152.
N Bachner-Hinenzon O Ertracht A Malka M Leitman Z Vered O Binah D Adam 《American journal of physiology. Heart and circulatory physiology》2012,303(5):H549-H558
Myocardial infarction (MI) injury extends from the endocardium toward the epicardium. This phenomenon should be taken into consideration in the detection of MI. To study the extent of damage at different stages of MI, we hypothesized that measurement of layer-specific strain will allow better delineation of the MI extent than total wall thickness strain at acute stages but not at chronic stages, when fibrosis and remodeling have already occurred. After baseline echocardiography scans had been obtained, 24 rats underwent occlusion of the left anterior descending coronary artery for 30 min followed by reperfusion. Thirteen rats were rescanned at 24 h post-MI and eleven rats at 2 wk post-MI. Next, rats were euthanized, and histological analysis for MI size was performed. Echocardiographic scans were postprocessed by a layer-specific speckle tracking program to measure the peak circumferential strain (S(C)(peak)) at the endocardium, midlayer, and epicardium as well as total wall thickness S(C)(peak). Linear regression for MI size versus S(C)(peak) showed that the slope was steeper for the endocardium compared with the other layers (P < 0.001), meaning that the endocardium was more sensitive to MI size than the other layers. Moreover, receiver operating characteristics analysis yielded better sensitivity and specificity in the detection of MI using endocardial S(C)(peak) instead of total wall thickness S(C)(peak) at 24 h post-MI (P < 0.05) but not 2 wk later. In conclusion, at acute stages of MI, before collagen deposition, scar tissue formation, and remodeling have occurred, damage may be nontransmural, and thus the use of endocardial S(C)(peak) is advantageous over total wall thickness S(C)(peak). 相似文献
153.
Padler-Karavani V Song X Yu H Hurtado-Ziola N Huang S Muthana S Chokhawala HA Cheng J Verhagen A Langereis MA Kleene R Schachner M de Groot RJ Lasanajak Y Matsuda H Schwab R Chen X Smith DF Cummings RD Varki A 《The Journal of biological chemistry》2012,287(27):22593-22608
DNA and protein arrays are commonly accepted as powerful exploratory tools in research. This has mainly been achieved by the establishment of proper guidelines for quality control, allowing cross-comparison between different array platforms. As a natural extension, glycan microarrays were subsequently developed, and recent advances using such arrays have greatly enhanced our understanding of protein-glycan recognition in nature. However, although it is assumed that biologically significant protein-glycan binding is robustly detected by glycan microarrays, there are wide variations in the methods used to produce, present, couple, and detect glycans, and systematic cross-comparisons are lacking. We address these issues by comparing two arrays that together represent the marked diversity of sialic acid modifications, linkages, and underlying glycans in nature, including some identical motifs. We compare and contrast binding interactions with various known and novel plant, vertebrate, and viral sialic acid-recognizing proteins and present a technical advance for assessing specificity using mild periodate oxidation of the sialic acid chain. These data demonstrate both the diversity of sialic acids and the analytical power of glycan arrays, showing that different presentations in different formats provide useful and complementary interpretations of glycan-binding protein specificity. They also highlight important challenges and questions for the future of glycan array technology and suggest that glycan arrays with similar glycan structures cannot be simply assumed to give similar results. 相似文献
154.
Maytal-Kivity V Pick E Piran R Hofmann K Glickman MH 《The international journal of biochemistry & cell biology》2003,35(5):706-715
The COP9 signalosome (CSN), the lid subcomplex of the proteasome and translational initiation factor 3 (eIF3) share structural similarities and are often referred to as the PCI family of complexes. In multicellular eukaryotes, the CSN is highly conserved as an 8-subunit complex but in Saccharomyces cerevisiae the complex is rather divergent. We further characterize the composition and properties of the CSN in budding yeast and its interactions with these related complexes. Using the generalized profile method we identified CSN candidates, four with PCI domains: Csn9, Csn10, Pci8/Csn11, and Csn12, and one with an MPN domain, Csn5/Rri1. These proteins and an additional interactor, Csi1, were tested for pairwise interactions by yeast two-hybrid and were found to form a cluster surrounding Csn12. Csn5 and Csn12 cofractionate in a complexed form with an apparent molecular weight of roughly 250kDa. However, Csn5 migrates as a monomer in Deltacsn12 supporting the pivotal role of Csn12 in stabilizing the complex. Confocal fluorescence microscopy detects GFP-tagged Csn5 preferentially in the nucleus, whereas in absence of Csn12, Csn10, Pci8/Csn11, or Csi1, Csn5 is delocalized throughout the cell, indicating that multiple subunits are required for nuclear localization of Csn5. Two CSN subunits, Csn9 and Csi1, interact with the proteasome lid subunit Rpn5. Pci8/Csn11 has previously been shown to interact with eIF3. Together, these results point to a network of interactions between these three structurally similar, yet functionally diverse, complexes. 相似文献
155.
Caburet S Zavadakova P Ben-Neriah Z Bouhali K Dipietromaria A Charon C Besse C Laissue P Chalifa-Caspi V Christin-Maitre S Vaiman D Levi G Veitia RA Fellous M 《PloS one》2012,7(3):e33412
Background
The human condition known as Premature Ovarian Failure (POF) is characterized by loss of ovarian function before the age of 40. A majority of POF cases are sporadic, but 10–15% are familial, suggesting a genetic origin of the disease. Although several causal mutations have been identified, the etiology of POF is still unknown for about 90% of the patients.Methodology/Principal Findings
We report a genome-wide linkage and homozygosity analysis in one large consanguineous Middle-Eastern POF-affected family presenting an autosomal recessive pattern of inheritance. We identified two regions with a LODmax of 3.26 on chromosome 7p21.1-15.3 and 7q21.3-22.2, which are supported as candidate regions by homozygosity mapping. Sequencing of the coding exons and known regulatory sequences of three candidate genes (DLX5, DLX6 and DSS1) included within the largest region did not reveal any causal mutations.Conclusions/Significance
We detect two novel POF-associated loci on human chromosome 7, opening the way to the identification of new genes involved in the control of ovarian development and function. 相似文献156.
M Vered Y Burstein A Gertler 《International journal of peptide and protein research》1985,25(1):76-84
Elastin was fully solubilized by digestion with elastase I or elastase II. Each digest was separated into high-molecular weight and low-molecular weight fractions that were characterized by the correspondence to their amino acid content, N-terminal sequence and C-terminal amino acids. It was found that although the relative amount of amino acids in the low-molecular weight fraction obtained by digestion with elastase I was lower than in digestion with elastase II, no major difference in the type of bonds cleaved in the low- or high-molecular weight fractions of each digest could be seen. There is, however, a remarkable difference in the type of bond cleaved by the two enzymes. While elastase I cleaves mostly Ala-Ala and also Ala-Gly bonds, elastase II hydrolyzes Leu-Ala, Leu-Gly, Phe-Ala, Phe-Gly and Tyr-Ala, Tyr-Gly bonds. Theoretical calculations led us to suggest both digests are composed of cross-linked peptides that vary not only in the molecular size but also in the number of cross-links found in peptides of the same size. 相似文献
157.
158.
Plant response to stress meets dedifferentiation 总被引:1,自引:0,他引:1
159.
The Negev Desert is characterized by low soil-water availability and organic matter content, as well as important factors significantly influencing soil biological activity. In order to overcome the xeric environment, plant and soil biota have evolutionarily developed, over time, ecophysiological abilities that help them fulfill their biological role and function. Microorganisms are known as a major part of the ecosystem's total biomass and play an important role in decomposition processes and the nutrient cycle. Perennial shrubs have been found to play an important role as organic matter suppliers and as a physical barrier prolonging biological activity of microbial communities. Soil samples were collected monthly, from November 2006 to November 2007, from a 0 to 10-cm depth under the canopies of Reaumuria negevensis and from open areas (control) in order to evaluate abiotic components and microbial variables on a temporal basis. H' values, evenness, and β diversity (S?rensen's similarity) were determined by a molecular method based on sequencing. Water availability, organic matter content, and total soluble nitrogen were higher in soil samples collected in the vicinity of R. negevensis than in samples collected in open areas. Our study also indicated that, in spite of the similarity between H' values of soil samples collected in the vicinity of R. negevensis and the open area, a low percentage of similarity was found between the soil bacterial populations. These results support the hypothesis that distribution of resources in the environment under R. negevensis shrubs varies in space and time and also influences soil microbial diversity and the abiotic environmental role. 相似文献
160.
Callus induction and formation were successfully achieved using stem segments of grapevine cv. Chardonnay. Nodal stem segments
from in vitro plantlets and internodal segments from field-grown plants of grapevine were used. The segments were placed in
an inverted and upright position in hormone-free medium or in medium supplemented with 1.1 mg/l naphthalene acetic acid and
0.45 mg/l benzyladenine. Firm, compact callus with pro-meristematic clusters was induced on the inverted segments within 10–20 days,
while only small calluses and roots appeared on the upright segments. Vascular cells (xylem and phloem) were differentiated
and maintained for more than 2 years in consecutive subcultures. The results show that inverting the position of grapevine
stem segments in vitro is a simple method for producing firm callus with pro-meristematic clusters. 相似文献