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Oxygen is of fundamental importance for most living organisms, and the maintenance of oxygen homeostasis is a key physiological challenge for all large animals. Oxygen deprivation, hypoxia, is a critical component of many human diseases including cancer, heart disease, stroke, vascular disease, and anaemia. The discovery of oxygen sensing provides fundamental knowledge of a stunningly elegant molecular machinery; it also promises development of new therapeutics for serious diseases such as cancer. As a result of their impressive contributions to our understanding of the mechanisms by which cells sense oxygen and signal in hypoxia, Gregg Semenza, Peter Ratcliffe, and William Kaelin were awarded the Nobel Prize in 2019.  相似文献   
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Platelet Endothelial Cell Adhesion Molecule 1 (PECAM-1) deficient mice in the FVB/n strain exhibit fatal chronic pulmonary fibrotic disease. The illness occurs in the absence of a detectable pro-inflammatory event. PECAM-1 is vital to the stability of vascular permeability, leukocyte extravasation, clotting of platelets, and clearance of apoptotic cells. We show here that the spontaneous development of fibrotic disease in PECAM-1 deficient FVB/n mice is characterized by early loss of vascular integrity in pulmonary capillaries, resulting in spontaneous microbleeds. Hemosiderin-positive macrophages were found in interstitial spaces and bronchoalveolar lavage (BAL) fluid in relatively healthy animals. We also observed a gradually increasing presence of hemosiderin-positive macrophages and fibrin deposition in the advanced stages of disease, corresponding to the accumulation of collagen, IL-10 expression, and myofibroblasts expressing alpha smooth muscle actin (SMA). Together with the growing evidence that pulmonary microbleeds and coagulation play an active part in human pulmonary fibrosis, this data further supports our hypothesis that PECAM-1 expression is necessary for vascular barrier function control and regulation of homeostasis specifically, in the pulmonary environment.  相似文献   
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An easy and efficient route to synthesize gel materials based on polymeric ionic liquids (PILs) is presented. The radical polymerization of imidazolium (Im)‐based ionic liquids (ILs) bearing a vinyl group ([VEIm][Br], [VEIm][Ac], [VBIm][Br], [VBIm][Cl]) with crosslinker (CL) N,N′‐methylenebisacrylamide (Bis) in water results in polyionic liquid hydrogels. Thermal and mechanical properties (tensile and compression tests) are investigated and compared with two different types of hydrogels. One is a polyacrylamide (PAAm) hydrogel having covalent‐type crosslinking. The other is an alginate‐based hydrogel having ionic‐type crosslinking. Prepared IL‐hydrogel materials provide favorable flexibility, adjustable by varying the CL ratio and water content. The higher the CL ratio is, the higher the fragility of the gel matrix. The gelation time of the hydrogels depends on the alkyl chain length, as well as the size of the anion.

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Background:In 2008 a Nordic collaboration was established between the quality registries in Denmark, Iceland, Norway, and Sweden to improve quality of care for children with diabetes. This study aimed to describe those registries and confirm that the registry variables are comparable. Selected variables were used to demonstrate outcome measurements.Methods:The organization of the registries and methodology are described. Cross-sectional data for patients between birth and 14.9 years with type 1 diabetes mellitus in 2009 (n = 6523) from 89 centers were analyzed. Variables were age, gender, and diabetic ketoacidosis at onset, together with age, gender, HbA1c, insulin regimen, and severe hypoglycemia at follow-up in 2009.Results:All 4 registries use a standardized registration at the onset of diabetes and at follow-up, conducted at the local pediatric diabetes centers. Methods for measuring HbA1c varied as did methods of registration for factors such as hypoglycemia. No differences were found between the outcomes of the clinical variables at onset. Significant variations were found at follow-up for mean HbA1c, the proportion of children with HbA1c < 57 mmol/mol (NGSP/DCCT 7.4%), (range 15-31%), the proportion with insulin pumps (range 34-55%), and the numbers with severe hypoglycemia (range 5.6-8.3/100 patient years).Conclusions:In this large unselected population from 4 Nordic countries, a high proportion did not reach their treatment target, indicating a need to improve the quality of pediatric diabetes care. International collaboration is needed to develop and harmonize quality indicators and offers possibilities to study large geographic populations, identify problems, and share knowledge.  相似文献   
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