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101.
As an emerging disease, the porcine epidemic diarrhoea virus has caused substantial economic losses to the pork industry in Mexico, leading to piglet mortality rates of up to 100%. For detection, sequencing and genetic characterization of the virus, 68 samples of one‐week‐old piglets from pork farms in 17 states of Mexico were analysed. In total, 53 samples were positive by real‐time RT‐PCR, confirming the presence of the virus in 15 states. Twenty‐eight samples from 10 states were amplified by endpoint RT‐PCR, and 20 sequences of the spike gene were obtained. A phylogenetic analysis based on the spike gene demonstrated that all Mexican strains are in Group II and are classified as non‐Indel‐S emerging variants. Three strains showed amino acid insertions: PEDv/MEX/GTO/LI‐DMZC15/2015 and PEDv/MEX/QRO/LI‐DMZC45/2016 showed one amino acid insertion (424Y425 and 447D448, respectively), and PEDv/MEX/QRO/LI‐DMZC49/2019 showed one and two amino acid insertions (422C423 and 537SQ538), with the second insertion in the COE region. These results provide evidence of the prevalence of emerging, non‐Indel‐S strains of the virus are currently circulating in Mexico during 2016–2018, when three of which have amino acid insertions: PEDv/MEX/GTO/IN‐DMZC15/2015 and PEDv/MEX/QRO/IN‐DMZC45/2016 have one amino acid insertion each (424Y425 and 447D448, respectively), and PEDv/MEX/QRO/IN‐DMZC49/2019 has one (422C423) and two amino acid insertions (537SQ538), the latter being in the COE region, which could generate new antigenic variants.  相似文献   
102.
The degradation of organic pollutants in wastewaters assisted by oxide semiconductor nanostructures has been the focus of many research groups over the last decades, along with the synthesis of these nanomaterials by simple, eco-friendly, fast, and cost-effective processes. In this work, porous zinc oxide (ZnO) nanostructures were successfully synthesized via a microwave hydrothermal process. A layered zinc hydroxide carbonate (LZHC) precursor was obtained after 15 min of synthesis and submitted to different calcination temperatures to convert it into porous ZnO nanostructures. The influence of the calcination temperature (300, 500, and 700 °C) on the morphological, structural, and optical properties of the ZnO nanostructureswas investigated. All ZnO samples were tested as photocatalysts in the degradation of rhodamine B (RhB) under UV irradiation and natural sunlight. All samples showed enhanced photocatalytic activity under both light sources, with RhB being practically degraded within 60 min in both situations. The porous ZnO obtained at 700 °C showed the greatest photocatalytic activity due to its high crystallinity, with a degradation rate of 0.091 and 0.084 min−1 for UV light and sunlight, respectively. These results are a very important step towards the use of oxide semiconductors in the degradation of water pollutants mediated by natural sunlight.  相似文献   
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104.
BackgroundPatient blood management (PBM) is an evidence-based care bundle with proven ability to improve patients’ outcomes by managing and preserving the patient’s own blood. Since 2010, the World Health Organisation has urged member states to implement PBM. However, there has been limited progress in developing PBM programmes in hospitals due to the implicit challenges of implementing them. To address these challenges, we developed a Maturity Assessment Model (MAPBM) to assist healthcare organisations to measure, benchmark, assess in PBM, and communicate the results of their PBM programmes. We describe the MAPBM model, its benchmarking programme, and the feasibility of implementing it nationwide in Spain.Materials and methodsThe MAPBM considers the three dimensions of a transformation effort (structure, process and outcomes) and grades these within a maturity scale matrix. Each dimension includes the various drivers of a PBM programme, and their corresponding measures and key performance indicators. The structure measures are qualitative, and obtained using a survey and structured self-assessment checklist. The key performance indicators for process and outcomes are quantitative, and based on clinical data from the hospitals’ electronic medical records. Key performance indicators for process address major clinical recommendations in each PBM pillar, and are applied to six common procedures characterised by significant blood loss.ResultsIn its first 5 years, the MAPBM was deployed in 59 hospitals and used to analyse 181,826 hospital episodes, which proves the feasibility of implementing a sustainable model to measure and compare PBM clinical practice and outcomes across hospitals in Spain.ConclusionThe MAPBM initiative aims to become a useful tool for healthcare organisations to implement PBM programmes and improve patients’ safety and outcomes.  相似文献   
105.
Identification of the hemangioblast in postnatal life   总被引:28,自引:11,他引:28  
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106.
This study analyses the clinical course of five patients who developed acute ascending aortic dissection 45.8 months (17-87 months) after aortic valve replacement (AVR) and underwent reoperation in our Department. All except one had aortic insufficiency with mild dilatation of the ascending aorta. No evidence of aortic wall degeneration was present at the time of AVR. Prostheses implanted were: Hancock 2, St. Jude 2, Bjork-Shiley 1. Associated procedures (coartectomy, coronary artery by-pass) were carried out in two patients. The dilated aorta was managed at the first operation by longitudinal resection in 3 of them. Emergent aortic dissection repair was performed: in 3 cases with composite graft according to the Bentall procedure, in one case with non valved dacron conduit and in the last case with teflon patch. Histological examination of the dissected aortic wall showed elastic fiber degeneration like cystic medial necrosis. Three patients survived surgical repair and are doing well at 22.4 months of mean post-operative follow-up. Surgical strategy of this complication is discussed; particular emphasis is given to the method of treatment of ascending aorta dilatation during AVR.  相似文献   
107.
Postprandial state is a pro-inflammatory condition associated with a transient impairment of endothelial function. Recent evidence suggests that myeloperoxidase (MPO) and matrix metalloproteinase-9 (MMP-9) are involved in the pathogenesis of inflammatory vascular diseases such as atherosclerosis. The present study was carried out to investigate whether a fat meal induces polymorphonuclear (PMN) activation and increases the plasma activity of MPO and MMP-9 and whether postprandial serum exerts pro-apoptotic effects on endothelial cells. Fifteen healthy young men underwent a high-fat challenge containing 60g butter. Blood samples were drawn before, and 1, 2, and 4h after the meal. Leukocyte reactive oxygen species (ROS) production, plasma MPO and MMP-9 activity, endothelial-derived soluble CD146 levels, and advanced oxidation protein product (AOPP) levels were determined. Human umbilical vein endothelial cells (HUVECs) were treated with human sera to evaluate mitochondrial membrane potential, ROS production, annexin PI staining, and caspase-3 activity. Triglycerides, ROS production, MPO activity, AOPP levels, pro-MMP-9 zymographic activity, and soluble CD146 levels significantly increased during the 4h after the test meal. Postprandial serum significantly decreased the mitochondrial membrane potential, and increased the rate of ROS production, the percentage of annexin-positive HUVECs, and caspase-3 activity. A strong relationship was observed between postprandial increase in PMN-derived MPO and pro-MMP-9 activity, and the increased rate of apoptosis of endothelial cells exposed to postprandial serum. Data show that postprandial serum exerts pro-apoptotic effects on endothelial cells. The close relationships between markers of endothelial cell apoptosis and MPO and pro-MMP-9 activity suggest that the latter may contribute to the development of fat meal induced endothelial damage.  相似文献   
108.
A novel nonmyeloablative conditioning regimen was investigated in 44 patients with hematologic malignancies. The median patient age was 41 years. Many of the patients had high-risk features, including 19 patients with a previous failed transplant. Recipient conditioning consisted of CAMPATH-1H, 20 mg/day on days -8 to -4; fludarabine, 30 mg/m(2) on days -7 to -3; and melphalan, 140 mg/m(2) on day -2. Thirty-six recipients received unmanipulated granculocyte colony-stimulating factor-mobilized peripheral blood stem cells from HLA-identical siblings, and 8 received unmanipulated marrow from matched unrelated donors. GVHD prophylaxis was with cyclosporine A alone for 38 patients and cyclosporine A plus methotrexate for 6 sibling recipients. Forty-two of the 43 evaluable patients had sustained engraftment. Results of chimerism analysis using microsatellite polymerase chain reaction indicate that 18 of 31 patients studied were full-donor chimeras while the other patients were mixed chimeras in one or more lineages. At a median follow-up of 9 months (range 3 to 29 months), 33 patients remain alive in complete remission or with no evidence of disease progression. Seven patients relapsed or progressed post-transplantation, and 4 of them subsequently died. Four patients died of regimen-related complications. There were no cases of grades III-IV acute GVHD. Only 2 patients developed grade II acute GVHD, and only 1 had chronic GVHD. The estimated probability of nonrelapse mortality was 11%. Although longer follow-up is needed to establish the long-term remission rates, this study demonstrates that this nonmyeloablative preparative regimen is associated with durable engraftment, minimal toxicity, and low incidence of GVHD.  相似文献   
109.
Maternal obesity and gestational diabetes mellitus (GDM) are associated with obesity and diabetes risk in offspring. We tested whether maternal insulin resistance, which frequently coexists with GDM and obesity, could independently contribute to dysregulation of offspring metabolism. Female mice haploinsufficient for insulin receptor substrate-1 (IRS1-het) are hyperinsulinemic and insulin resistant during pregnancy, despite normal plasma glucose and body weight, and thus serve as a model of isolated maternal insulin resistance. Wild-type (WT) offspring of IRS1-het dams insulin resistance-exposed [IR-exposed] were compared with WT offspring of WT dams. Despite no differences in adiposity, male IR-exposed pups were glucose intolerant (P = 0.04) and hyperinsulinemic (1.3-fold increase, P = 0.02) by 1 month of age and developed progressive fasting hyperglycemia. Moreover, male IR-exposed pups challenged with high-fat diet exhibited insulin resistance. Liver lipidomic analysis of 3-week-old IR-exposed males revealed increases in the 16:1n7 fraction of several lipid classes, suggesting increased Scd1 activity. By 6 months of age, IR-exposed males had increased lipid accumulation in liver as well as increased plasma refed fatty acids, consistent with disrupted lipid metabolism. Our results indicate that isolated maternal insulin resistance, even in the absence of hyperglycemia or obesity, can promote metabolic perturbations in male offspring.  相似文献   
110.
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