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Kathryn L. Butler Vijayakrishnan Ambravaneswaran Nitin Agrawal Maryelizabeth Bilodeau Mehmet Toner Ronald G. Tompkins Shawn Fagan Daniel Irimia 《PloS one》2010,5(7)
Thermal injury triggers a fulminant inflammatory cascade that heralds shock, end-organ failure, and ultimately sepsis and death. Emerging evidence points to a critical role for the innate immune system, and several studies had documented concurrent impairment in neutrophil chemotaxis with these post-burn inflammatory changes. While a few studies suggest that a link between neutrophil motility and patient mortality might exist, so far, cumbersome assays have prohibited exploration of the prognostic and diagnostic significance of chemotaxis after burn injury. To address this need, we developed a microfluidic device that is simple to operate and allows for precise and robust measurements of chemotaxis speed and persistence characteristics at single-cell resolution. Using this assay, we established a reference set of migration speed values for neutrophils from healthy subjects. Comparisons with samples from burn patients revealed impaired directional migration speed starting as early as 24 hours after burn injury, reaching a minimum at 72–120 hours, correlated to the size of the burn injury and potentially serving as an early indicator for concurrent infections. Further characterization of neutrophil chemotaxis using this new assay may have important diagnostic implications not only for burn patients but also for patients afflicted by other diseases that compromise neutrophil functions. 相似文献
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Zhaohua Zhang LiLi Ge Shanshan Zhang Jue Wang Wen Jiang Qian Xin Yun Luan 《Journal of cellular and molecular medicine》2020,24(23):13938
The aim of the study was to explore the mechanism of mesenchymal stem cell‐derived exosomes (MSC‐EXO) to protect against experimentally induced pulmonary hypertension (PH). Monocrotaline (MCT)‐induced rat model of PH was successfully established by a single intraperitoneal injection of 50 mg/kg MCT, 3 weeks later the animals were treated with MSC‐EXO via tail vein injection. Post‐operation, our results showed that MSC‐EXO could significantly reduce right ventricular systolic pressure (RVSP) and the right ventricular hypertrophy index, attenuate pulmonary vascular remodelling and lung fibrosis in vivo. In vitro experiment, the hypoxia models of pulmonary artery endothelial cell (PAEC) and pulmonary vascular smooth muscle cell (PASMC) were used. We found that the expression levels of Wnt5a, Wnt11, BMPR2, BMP4 and BMP9 were increased, but β‐catenin, cyclin D1 and TGF‐β1 were decreased in MSC‐EXO group as compared with MCT or hypoxia group in vivo or vitro. However, these increased could be blocked when cells were transfected with Wnt5a siRNA in vitro. Taken together, these results suggested that the mechanism of MSC‐EXO to prevent PH vascular remodelling may be via regulation of Wnt5a/BMP signalling pathway. 相似文献
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Hyperthermic treatment at 43 degrees C suppressed the growth of Ehrlich ascites tumor (EAT) cells in vitro. Incubation of EAT cells at 43 degrees C for as little as 1.5 h totally abolished the transplantability of the tumor. At the same time, the rate of cellular glucose uptake, the density of glucose transporter on the cells as well as the extent of thymidine, uridine and leucine incorporation were significantly reduced. 相似文献
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The Invisibility of Disability: Using Dance to Shake from Bioethics the Idea of ‘Broken Bodies’ 下载免费PDF全文
Shawn H.E. Harmon 《Bioethics》2015,29(7):488-498
Complex social and ethical problems are often most effectively solved by engaging them at the messy and uncomfortable intersections of disciplines and practices, a notion that grounds the InVisible Difference project, which seeks to extend thinking and alter practice around the making, status, ownership, and value of work by contemporary dance choreographers by examining choreographic work through the lenses of law, bioethics, dance scholarship, and the practice of dance by differently‐abled dancers. This article offers a critical thesis on how bioethics has come to occupy a marginal and marginalizing role in questions about the differently‐abled body. In doing so, it has rendered the disabled community largely invisible to and in bioethics. It then defends the claim that bioethics – as a social undertaking pursued collaboratively by individuals from different disciplines – must take much better notice of the body and the embodied individual if it is to better achieve its ends, which include constructing a moral and just society. Finally, this article considers how the arts, and specifically dance (and here dance by differently‐abled dancers), provides us with rich evidence about the body and our ability to respond positively to normally ‘othered’ bodies. It concludes that greater attention to empirical evidence like that being generated in InVisible Difference will help to expand the reach and significance of bioethics, and thereby its relevance to (and consciousness of) important questions about the status of bodies and bodily differences, which must be considered as central to its ambitions. 相似文献