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Background Platelets play a pivotal role in the pathogenesis of the thrombotic complications in cardiovascular disease (CVD). Abnormal
platelet activation indices are evolving as potentially useful markers in CVD risk stratification. Whilst there has been some
investigation into the effects of storage time on several of these indices, the effects of underlying disease severity on
these temporal changes have not been previously studied.
Methods Using the ADVIATM120 haematology analyser, we assessed the effects of time-dependent storage of whole blood in EDTA, on a number of platelet
activation indices: mean platelet volume (MPV), mean platelet component (MPC, measure of platelet density) and platelet component
distribution width (PCDW, a marker of platelet shape change. We studied three age- and sex-matched patient groups: (i) healthy
controls (n = 10), (ii) stable patients with coronary artery disease (CAD, n = 9); and (iii) patients with acute myocardial infarction (n = 8). Whole blood samples were processed at exactly 5 min following venesection and at 15, 30, 60 and 120 min later in storage
in EDTA tubes at room temperature.
Results There was a significant and stepwise increase in MPV (P = 0.01) and decrease in PCDW (P = 0.03), with a non-significant trend to increasing MPM and decreasing MPC with increasing underlying disease (that is healthy,
‘stable’ and ‘acute’ artery disease). There was a significant time-dependent increase in MPV and decrease in MPC and PCDW
(all P < 0.05), which were all significant on ‘post-hoc’ analyses by 30 min. There were no significant changes in platelet count
or MPM with time. There was no interaction of underlying disease with whole-blood storage time for any of the platelet indices
reported (P = NS).
Conclusion There is a temporal increase in MPV and decrease in MPC and PCDW in venous blood stored over 2 h in EDTA. These changes are
not influenced by the underlying CVD disease severity. 相似文献
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Cutaneous vasculitis associated with rifampin therapy 总被引:1,自引:0,他引:1
Immune complex-mediated vasculitis is a well-recognized form of idiosyncratic drug reaction. We report cutaneous vasculitis in association with therapy with rifampin (rifampicin). To our knowledge, this has not previously been documented. Rifampin is widely used, and such reactions are therefore important to note. 相似文献
16.
K. Balu 《Journal of Indian Prosthodontic Society》2013,13(4):621-626
Loss of maxillo facial structures due to neoplasm, trauma and accidents gives inconsolable mental, physical and psychological agony to a person’s dignified life in his living society. Surgical reconstruction was not feasible for all cases and certain cases needs prosthetic rehabilitation. In this clinical case report, an innovative, simple three part maxillo orbital prosthesis fabrication using magnets was explained. 相似文献
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Buer Sen Christopher R Paradise Zhihui Xie Jeyantt Sankaran Gunes Uzer Maya Styner Mark Meyer Amel Dudakovic Andre J van Wijnen Janet Rubin 《Journal of bone and mineral research》2020,35(6):1149-1162
During bone marrow stromal cell (BMSC) differentiation, both Wnt signaling and the development of a rigid cytoskeleton promote commitment to the osteoblastic over adipogenic lineage. β-catenin plays a critical role in the Wnt signaling pathway to facilitate downstream effects on gene expression. We show that β-catenin was additive with cytoskeletal signals to prevent adipogenesis, and β-catenin knockdown promoted adipogenesis even when the actin cytoskeleton was depolymerized. β-catenin also prevented osteoblast commitment in a cytoskeletal-independent manner, with β-catenin knockdown enhancing lineage commitment. Chromatin immunoprecipitation (ChIP)-sequencing demonstrated binding of β-catenin to the promoter of enhancer of zeste homolog 2 (EZH2), a key component of the polycomb repressive complex 2 (PRC2) complex that catalyzes histone methylation. Knockdown of β-catenin reduced EZH2 protein levels and decreased methylated histone 3 (H3K27me3) at osteogenic loci. Further, when EZH2 was inhibited, β-catenin's anti-differentiation effects were lost. These results indicate that regulating EZH2 activity is key to β-catenin's effects on BMSCs to preserve multipotentiality. © 2020 American Society for Bone and Mineral Research. 相似文献
19.
The concentration-activity profiles for insulin and insulin-like growth factor I (IGF-I; in the presence of and insulin-like growth factor I (IGF-I; in the presence of hydrocortisone and PRL) have been compared in terms of the accumulation of beta-casein mRNA, total casein synthesis, and alpha-lactalbumin and basal carrier-mediated glucose transport activities in mammary epithelial cells from midpregnant mice. For the accumulation of the casein mRNA and the induction of casein synthesis and alpha-lactalbumin activity, the insulin ED50 is 1-2 ng/ml, while that for IGF-I is 10- to 20-fold greater. The effects of insulin and IGF-I are not additive in these instances. For the induction of basal carrier-mediated glucose transport, the insulin ED50 is 8 ng/ml, and that for IGF-I is 16 ng/ml. Either factor can induce transport activity up to the level present in the cells from 2-day lactating mice. In this instance the effects are additive; insulin and IGF-I together can induce the transport up to the 10-day lactating level. 相似文献
20.
Weiss BP Kim SS Kirschvink JL Kopp RE Sankaran M Kobayashi A Komeili A 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(22):8281-8284
Transmission electron microscopy studies have been used to argue that magnetite crystals in carbonate from Martian meteorite ALH84001 have a composition and morphology indistinguishable from that of magnetotactic bacteria. It has even been claimed from scanning electron microscopy imaging that some ALH84001 magnetite crystals are aligned in chains. Alignment of magnetosomes in chains is perhaps the most distinctive of the six crystallographic properties thought to be collectively unique to magnetofossils. Here we use three rock magnetic techniques, low-temperature cycling, the Moskowitz test, and ferromagnetic resonance, to sense the bulk composition and crystallography of millions of ALH84001 magnetite crystals. The magnetic data demonstrate that although the magnetite is unusually pure and fine-grained in a manner similar to terrestrial magnetofossils, most or all of the crystals are not arranged in chains. 相似文献