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101.
Kris Gillis Gezim Bala Bram Roosens Isabel Remory Sophie Hernot Steven Droogmans Bernard Cosyns 《PloS one》2016,11(2)
Purpose
Calcification is an important prognostic factor in aortic valve stenosis. However, there is no ultrasound (US) method available to accurately quantify calcification in this setting to date. We aimed to validate a new US method for measuring the amount of calcium in an in vitro model, and compare it to computed tomography (CT), the current imaging gold standard.Materials and Methods
An agar phantom (2% agar) was made, containing 9 different amounts of calcium-hydroxyapatite Ca5(PO4)3OH (2 to 50mg). The phantoms were imaged with micro-CT and US (10 MHz probe). The calcium area (areacalcium) and its maximum pixel value (PVmax) were obtained. These values were summed to calculate CT and US calcium scores (∑(areacalcium × PVmax)) and volumes (∑areacalcium). Both US- and CT-calcium scores were compared with the calcium amounts, and with each other.Results
Both calcium scores correlated significantly with the calcium amount (R2 = 0.9788, p<0.0001 and R2 = 0.8154, p<0.0001 for CT and US respectively). Furthermore, there was a significant correlation between US and CT for calcium volumes (R2 = 0.7392, p<0.0001) and scores (R2 = 0.7391, p<0.0001).Conclusion
We developed a new US method that accurately quantifies the amount of calcium in an in vitro model. Moreover it is strongly correlated with CT. 相似文献102.
Jason B. Bram Jenifer E. Dugan 《Journal of experimental marine biology and ecology》2005,317(2):223-237
The effects of selected physical and biological factors on the early development of a subtidal invertebrate assemblage were examined at an offshore oil platform in the Santa Barbara Channel (California, USA). The effects of date, year, length, and depth of submersion were investigated by replacing sets of ceramic tiles with new tiles at frequencies of 2, 4, 6, 12, and 24 months at three depths (6, 12, and 18 m) over a period of 24 months. The effects of existing colonists and depth were explored in a second experiment by removing selected early colonists from ceramic tiles deployed at the same three depths over a period of 12 months. More than 40 invertebrate taxa from seven phyla colonized the tiles. Colonial tunicates and encrusting bryozoans appeared early in the successional sequence (∼2 months), in cover ranging from <5% to 80% and from <5% to 55%, respectively. Tubiculous amphipods, barnacles, and sponges could also appear early, but in low cover (<20%). Composition of the assemblage changed over time with barnacles, sponges, and mussels becoming the principal space holders on tiles submerged for 24 months. When potential competitors were removed monthly, variation in the cover of dominant taxa (i.e., bryozoans, amphipods, barnacles) was maintained to 12 months, suggesting that other factors, such as larval availability or post-settlement mortality, were responsible for these patterns. Development of this assemblage appeared to fit a pattern of early succession that was largely predictable in terms of the composition and sequence of occurrence of dominant taxa, but variable in rate of development, depending on date of submersion, year, and depth. 相似文献
103.
Teuntje M. J. C. Andriessen Bram Jacobs Pieter E. Vos 《Journal of cellular and molecular medicine》2010,14(10):2381-2392
Traumatic brain injury (TBI) is a frequent and clinically highly heterogeneous neurological disorder with large socioeconomic consequences. TBI severity classification, based on the hospital admission Glasgow Coma Scale (GCS) score, ranges from mild (GCS 13–15) and moderate (GCS 9–12) to severe (GCS ≤ 8). The GCS reflects the risk of dying from TBI, which is low after mild (∼1%), intermediate after moderate (up to 15%) and high (up to 40%) after severe TBI. Intracranial damage can be focal, such as epidural and subdural haematomas and parenchymal contusions, or diffuse, for example traumatic axonal injury and diffuse cerebral oedema, although this distinction is somewhat arbitrary. Study of the cellular and molecular post-traumatic processes is essential for the understanding of TBI pathophysiology but even more to find therapeutic targets for the development of neuroprotective drugs to be eventually used in human beings. To date, studies in vitro and in vivo, mainly in animals but also in human beings, are unravelling the pathological TBI mechanisms at high pace. Nevertheless, TBI pathophysiology is all but completely elucidated. Neuroprotective treatment studies in human beings have been disappointing thus far and have not resulted in commonly accepted drugs. This review presents an overview on the clinical aspects and the pathophysiology of focal and diffuse TBI, and it highlights several acknowledged important events that occur on molecular and cellular level after TBI. 相似文献
104.
P. Baudy S. Bram D. Vastel J. Lepault A. Kitzis 《Biochemical and biophysical research communications》1976,72(1):176-183
The small angle neutron scattering radii of gyration of 185 base pair subunits have been determined in H2O and D2O These values suggest that the outer diameter is 120 to 150Å. The results are not consistent with models in which all of the DNA is in an external shell. The neutron scattering profiles are in good agreement with a model based upon freeze etching electron microscopy (4) having two concentric coils of DNA with 80Åand 150Åexternal diameters. 相似文献
105.
Hayo H. W. Velthuis Bram Mabelis M. J. Sommeijer 《Entomologia Experimentalis et Applicata》1991,59(1):101-104
Book reviewed in this article: W. Engels (Ed.): Social Insects, an evolutionary approach to castes and reproduction. Hölldobler, B & E. O. Wilson, 1990. The ants The biology of the vespine wasps. By Makoto Matsuura and Seiki Yamane. 相似文献
106.
Heylen K Vanparys B Gevers D Wittebolle L Boon N De Vos P 《Environmental microbiology》2007,9(4):1072-1077
Gene sequence analysis of cnorB and qnorB, both encoding nitric oxide reductases, was performed on pure cultures of denitrifiers, for which previously nir genes were analysed. Only 30% of the 227 denitrifying strains rendered a norB amplicon. The cnorB gene was dominant in Alphaproteobacteria, and dominantly coexisted with the nirK gene, coding for the copper-containing nitrite reductase. Both norB genes were equally present in Betaproteobacteria but no linked distributional pattern of nir and norB genes could be observed. The overall cnorB phylogeny was not congruent with the widely accepted organism phylogeny based on 16S rRNA gene sequence analysis, with strains from different bacterial classes having identical cnorB sequences. Denitrifiers and non-denitrifiers could be distinguished through qnorB gene phylogeny, without further grouping at a higher taxonomic resolution. Comparison of nir and norB phylogeny revealed that genetic linkage of both genes is not widespread among denitrifiers. Thus, independent evolution of the genes for both nitrogen oxide reductases does also occur. 相似文献
107.
Prevalence of Coinfection with Gastric Non‐Helicobacter pylori Helicobacter (NHPH) Species in Helicobacter pylori‐infected Patients Suffering from Gastric Disease in Beijing,China 下载免费PDF全文
Jie Liu Lihua He Freddy Haesebrouck Yanan Gong Bram Flahou Qizhi Cao Jianzhong Zhang 《Helicobacter》2015,20(4):284-290
108.
van der Eerden BC Weissgerber P Fratzl-Zelman N Olausson J Hoenderop JG Schreuders-Koedam M Eijken M Roschger P de Vries TJ Chiba H Klaushofer K Flockerzi V Bindels RJ Freichel M van Leeuwen JP 《Journal of cellular physiology》2012,227(5):1951-1959
Bone is the major store for Ca(2+) in the body and plays an important role in Ca(2+) homeostasis. During bone formation and resorption Ca(2+) must be transported to and from bone by osteoblasts and osteoclasts, respectively. However, little is known about the Ca(2+) transport machinery in these bone cells. In this study, we examined the epithelial Ca(2+) channel TRPV6 in bone. TRPV6 mRNA is expressed in human and mouse osteoblast-like cells as well as in peripheral blood mononuclear cell-derived human osteoclasts and murine tibial bone marrow-derived osteoclasts. Also other transcellular Ca(2+) transport genes, calbindin-D(9k) and/or -D(28K), Na(+)/Ca(2+) exchanger 1, and plasma membrane Ca(2+) ATPase (PMCA1b) were expressed in these bone cell types. Immunofluorescence and confocal microscopy on human osteoblasts and osteoclasts and mouse osteoclasts revealed TRPV6 protein at the apical domain and PMCA1b at the osteoidal domain of osteoblasts, whereas in osteoclasts TRPV6 was predominantly found at the bone-facing site. TRPV6 was dynamically expressed in human osteoblasts, showing maximal expression during mineralization of the extracellular matrix. 1,25-Dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) did not change TRPV6 expression in both mineralizing and non-mineralizing SV-HFO cultures. Lentiviral transduction-mediated overexpression of TRPV6 in these cells did not alter mineralization. Bone microarchitecture and mineralization were unaffected in Trpv6(D541A/D541A) mice in which aspartate 541 in the pore region was replaced with alanine to render TRPV6 channels non-functional. In summary, TRPV6 and other proteins involved in transcellular Ca(2+) transport are dynamically expressed in bone cells, while TRPV6 appears not crucial for bone metabolism and matrix mineralization in mice. 相似文献
109.
Zane NA Gundelach JH Lindquist LD Bram RJ 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(7):3009-3018
Calcium-modulating cyclophilin ligand (CAML) is a ubiquitously expressed protein that is important during thymopoiesis. However, whether it serves a function in mature lymphocytes is unknown. In this article, we show that CAML is essential for survival of peripheral follicular (Fo) B cells. Conditional deletion of CAML in CD19-Cre transgenic mice caused a significant reduction in Fo cell numbers and increased rates of homeostatic proliferation. CAML-deficient Fo cells showed increased cellular turnover and normal proliferative ability. Although CAML-deficient Fo cells responded to AgR stimulation and to B cell activating factor, they displayed decreased survival and increased apoptosis following stimulation with LPS and IL-4 in vitro. Failure to survive was not due to aberrant B cell development in the absence of CAML, because induced deletion of the gene in mature cells resulted in a similar phenotype. These data establish an essential and ongoing role for CAML in the long-term survival of mature B cells. 相似文献
110.
Conservation agriculture, increased organic carbon in the top-soil macro-aggregates and reduced soil CO2 emissions 总被引:1,自引:0,他引:1
Mariela Fuentes Claudia Hidalgo Jorge Etchevers Fernando De León Armando Guerrero Luc Dendooven Nele Verhulst Bram Govaerts 《Plant and Soil》2012,355(1-2):183-197