76 research outputs found
Influence of the water vapor on the activity of CuO/SBA-15 SOx adsorbents
Both the performance and regenerability of SO2 adsorbents made of CuO supported on SBA-15 ordered mesoporous silica were studied for a cyclic DeSOx process under wet and dry conditions. H2O vapor decreases the performance of a 16 wt% loading CuO/SBA-15 (16CuO/SBA-15) adsorbent along the adsorption/regeneration cycles performed at 400 °C. Indeed, the SO2 breakthrough adsorption capacity of this adsorbent after ten adsorption- regeneration cycles under wet conditions (5 vol% of H2O) decreases of 61% compared to the SO2 performance obtained under dry conditions. The impact of the temperature as well as the CuO loading on the performance and regenerability of CuO/SBA-15 sorbents were also investigated under dry and wet conditions. XRD, TEM/EDX, N2 physisorption characterizations of the adsorbents were performed after the last cycle to correlate the structural and textural properties of the adsorbents and therefore the copper species, with the performance of the adsorbents. Increasing the temperature up to 450 °C with or without water increases the SO2 adsorption capacity of the 16CuO/SBA-15 adsorbent with higher SO2 adsorption capacity at 450 °C with water than without water. In the presence of water vapor, the 8CuO/SBA-15 adsorbent presents the highest average loss of SO2 adsorption capacity at the breakthrough of around 71% when expressed in mgSO2/gCuO , compared to the ones obtained with the 16CuO/SBA-15 and the 26CuO/SBA-15 adsorbents. The increase of the CuO loading up to 26 wt%, shows that the contribution of the surface copper active phase highlighted by the desorption curves, decreases significantly for the highest CuO loading under wet conditions. Moreover, with or without water, the highest total SO2 adsorption capacities obtained after the tenth cycle are observed for the lowest CuO loading (8 wt% of CuO: 547 and 495 mgSO2/gCuO without and with H2O, respectively). These higher total SO2 adsorption capacities could be explained by a better CuO phase dispersion on the SBA-15 support, which makes the copper active species more reactive especially with H2O
Breast cancer incidence highest in the range of one species of house mouse, Mus domesticus
Incidence of human breast cancer (HBC) varies geographically, but to date no environmental factor has explained this variation. Previously, we reported a 44% reduction in the incidence of breast cancer in women fully immunosuppressed following organ transplantation (Stewart et al (1995) Lancet346: 796–798). In mice infected with the mouse mammary tumour virus (MMTV), immunosuppression also reduces the incidence of mammary tumours. DNA with 95% identity to MMTV is detected in 40% of human breast tumours (Wang et al (1995) Cancer Res55: 5173–5179). These findings led us to ask whether the incidence of HBC could be correlated with the natural ranges of different species of wild mice. We found that the highest incidence of HBC worldwide occurs in lands where Mus domesticus is thse resident native or introduced species of house mouse. Given the similar responses of humans and mice to immunosuppression, the near identity between human and mouse MTV DNA sequences, and the close association between HBC incidence and mouse ranges, we propose that humans acquire MMTV from mice. This zoonotic theory for a mouse-viral cause of HBC allows testable predictions and has potential importance in prevention. © 2000 Cancer Research Campaig
ESC Working Group Cellular Biology of the Heart: Position Paper: Improving the pre-clinical assessment of novel cardioprotective therapies
Ischemic heart disease (IHD) remains the leading cause of death and disability worldwide. As a result, novel therapies are still needed to protect the heart from the detrimental effects of acute ischemia-reperfusion injury, in order to improve clinical outcomes in IHD patients. In this regard, although a large number of novel cardioprotective therapies discovered in the research laboratory have been investigated in the clinical setting, only a few of these have been demonstrated to improve clinical outcomes. One potential reason for this lack of success may have been the failure to thoroughly assess the cardioprotective efficacy of these novel therapies in suitably designed pre-clinical experimental animal models. Therefore, the aim of this Position Paper by the European Society of Cardiology Working Group Cellular Biology of the Heart is to provide recommendations for improving the pre-clinical assessment of novel cardioprotective therapies discovered in the research laboratory, with the aim of increasing the likelihood of success in translating these new treatments into improved clinical outcomes
Evaluation of autologous platelet rich plasma for cardiac surgery: outcome analysis of 2000 patients
Persistence of Simian Varicella Virus DNA in CD4+ and CD8+ Blood Mononuclear Cells for Years after Intratracheal Inoculation of African Green Monkeys
AbstractSimian varicella virus (SVV) DNA was detected in blood mononuclear cells (MNCs) of adult African green monkeys 7 days to 23 months after intratracheal inoculation with 103 plaque forming units. Infectious virus was not detected in MNCs at 14 months postinfection (p.i.), and electron microscopic (EM) analysis of MNCs from two monkeys 21 months p.i. did not reveal virus particles. Real-time quantitative PCR analysis of DNA from blood MNCs taken at multiple intervals from SVV-infected monkeys M7 and M8 revealed a 10- to 100-fold decrease, but not clearance of SVV DNA in MNCs between 11 and 17 months p.i. Thereafter, the SVV DNA copy number did not decrease further between 17 and 23 months p.i. PCR analysis of MNCs sorted by flow cytometry revealed SVV DNA in T cells (CD4+, CD8+) and B cells (CD20+), but not in monocyte-macrophages (CD14+), 10 days p.i. At 11 and 23 months p.i., SVV DNA was found exclusively in CD4+ and CD8+ T cells. Whether the detection of SVV DNA in CD4+ and CD8+ MNCs many months after the resolution of acute varicella reflects continued infection of these cells that began at the time of acute varicella or represents infection acquired by MNCs trafficking through infected tissues is unknown
Naturally Acquired Simian Varicella Virus Infection in African Green Monkeys
Simian varicella virus (SVV) infection of primates shares clinical, pathological, immunological, and virological features with varicella-zoster virus infection of humans. Natural varicella infection was simulated by exposing four SVV-seronegative monkeys to monkeys inoculated intratracheally with SVV, in which viral DNA and RNA persist in multiple tissues for more than 1 year (T. M. White, R. Mahalingam, V. Traina-Dorge, and D. H. Gilden, J. Neurovirol. 8:191-205, 2002). The four naturally exposed monkeys developed mild varicella 10 to 14 days later, and skin scrapings taken at the time of the rash contained SVV DNA. Analysis of multiple ganglia, liver, and lung tissues from the four naturally exposed monkeys sacrificed 6 to 8 weeks after resolution of the rash revealed SVV DNA in ganglia at multiple levels of the neuraxis but not in the lung or liver tissue of any of the four monkeys. This animal model provides an experimental system to gain information about varicella latency with direct relevance to the human disease
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