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排序方式: 共有6944条查询结果,搜索用时 15 毫秒
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Sandra De Barros Stéphanie Dehez Emmanuelle Arnaud Corinne Barreau Alexandre Cazavet Guillaume Perez Anne Galinier Louis Casteilla Valérie Planat-Bénard 《Molecular therapy》2013,21(2):399-408
Adipose stroma/stem cells (ASC) represent an ideal source of autologous cells for cell-based therapy. Their transplantation enhances neovascularization after experimental ischemic injury. Aging is associated with a progressive decrease in the regenerative potential of mesenchymal stem cells (MSCs) from bone marrow. This work aims to determine the aging effect on human ASC capacities. First, we show that aging impairs angiogenic capacities of human ASC (hASC) in a mouse ischemic hindlimb model. Although no change in hASC number, phenotype, and proliferation was observed with aging, several mechanisms involved in the adverse effects of aging have been identified in vitro combining a concomitant decrease in (i) ASC ability to differentiate towards endothelial cells, (ii) secretion of proangiogenic and pro-survival factors, and (iii) oxidative stress. These effects were counteracted by a hypoxic preconditioning that improved in vivo angiogenic capacities of hASC from older donors, while hASC from young donors that have a strong ability to manage hypoxic stress were not. Finally, we identified reactive oxygen species (ROS) generation as a key signal of hypoxia on hASC angiogenic capacities. This study demonstrates for the first time that age of donor impaired angiogenic capacities of hASC in ischemic muscle and change in ROS generation by hypoxic preconditioning reverse the adverse effect of aging. 相似文献
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Hand-held echocardiography (HHE) is being explored for use in the intensive care arena as an extension of the physical examination for real time and iterative information. HHE can help assess chamber size, ventricular function, and presence of fluid collections, and thus is useful in determining etiology of shock and measuring volume status. With additional outcomes and cost-effectiveness research, development of appropriate indications for HHE, and multisociety guidelines on competence assessment and quality control, HHE is expected to be increasingly integrated into intensive care medicine. 相似文献
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Marine Gaudry Pierre-Antoine Barral Arnaud Blanchard Sylvie Palazzolo Sonia Bolomey Virgile Omnes Mariangela De Masi Magali Carcopino-Tusoli Olivier Meyrignac Hervé Rousseau Alexis Jacquier Reda Hassen-Khodja Alessandra Bura-Rivière Jean-Michel Bartoli Stéphanie Gentile Philippe Piquet Laurence Bal 《European journal of vascular and endovascular surgery》2021,61(6):930-937
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Matthew J. Douma Christopher Picard Domhnall O’Dochartaigh Peter G. Brindley 《Prehospital emergency care》2019,23(4):538-542
Introduction: Following life-threatening junctional trauma, the goal is to limit blood loss while expediting transfer to operative rescue. Unfortunately, life-threatening abdominal-pelvic or junctional hemorrhage is often not amenable to direct compression and few temporizing strategies are available beyond hemostatic dressings, hypotensive resuscitation, and balanced transfusion. Objectives: In this study, we evaluated proximal external aortic compression to arrest blood flow in healthy adult men. Methods: This was a simulation trial of proximal external aortic compression, for life-threatening abdominal-pelvic and junctional hemorrhage, in a convenience sample of healthy adult male volunteers. The primary end points were cessation of femoral blood flow as assessed by pulse wave Doppler ultrasound at the right femoral artery, caudal to the inguinal ligament. Secondary end points were discomfort and negative sequelae. Results: Aortic blood flow was arrested in 12 volunteers. Median time to blood flow cessation was 12.5?seconds. Median reported discomfort was 5 out of 10. No complications or negative sequelae were reported. Conclusion: This trial suggests that it may be reasonable to attempt temporization of major abdominal-pelvic and junctional hemorrhage using bimanual proximal external aortic compression. In the absence of immediate alternatives for this dangerous and vexing injury pattern, there appear to be few downsides to prehospital proximal external aortic compression while concomitantly expediting definite care. 相似文献
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BACKGROUND: The authors recently pointed out an epidemiological relation between specific anti-Chlamydia pneumoniae antibodies and peripartum cardiomyopathy in Niamey (Republic of Niger). DESIGN: In this work, they studied the prognosis value of such specific antibodies. METHODS: The serological status for specific IgG, IgA and IgM anti-C. pneumoniae antibodies of 50 African women (age, mean+/-SD = 30.2 +/- 7 years) hospitalized in Niamey, with peripartum cardiomyopathy, was determined at the time of diagnosis. The diagnosis was categorized as 'complete remission' (13 patients, age = 29.3 +/- 6.5 years, observation delay = 27 months), 'incomplete remission' (27 patients, age = 30.7 +/- 7.6 years, observation delay = 14 months) and 'deceased' (10 patients, age = 30.3 +/- 6.2 years, observation delay = 13 months). The control group comprised 27 African women (age = 25.2 +/- 4.6 years), living in the same area. The Mann-Whitney and Fisher's exact tests were used for the statistical comparison. RESULTS: The dilution of IgG specific anti-C. pneumoniae antibodies was higher (P = 0.047) in the 'incomplete remission' compared with 'complete remission'. The dilution of IgA specific anti-C. pneumoniae antibodies was higher (P = 0.033) in the patients with a severe evolution ('deceased' + 'incomplete remission') compared with 'complete remission'. There was no significant difference between patients in 'complete remission' compared with 'controls'. CONCLUSIONS: At the time of peripartum cardiomyopathy diagnosis the specific IgG and IgA anti-C. pneumoniae antibodies are of prognosis value: a high dilution is more often associated with a poor prognosis. This is the first identified prognosis factor during the precocious evolution of peripartum cardiomyopathy. 相似文献
80.
Philippe Lévy Arnaud Boruchowicz Patrick Hastier Alexandre Pariente Thierry Thévenot Jean Louis Frossard Louis Buscail Fran?ois Mauvais Jean Claude Duchmann Alain Courrier Philippe Bulois Jean Louis Gineston Marc Barthet Henri Licht Dermot O'Toole Philippe Ruszniewski 《Pancreatology》2005,5(4-5):450-456
BACKGROUND: No study on bioclinical criteria predicting a biliary origin for acute pancreatitis has included endosonography as a reference examination. Re-examination of bioclinical parameters deserves consideration in the era where other causes are known (e.g. hereditary, autoimmune). AIM AND METHODS: To determine the performance of bioclinical markers in predicting a biliary origin of acute pancreatitis where the diagnosis of biliary lithiasis was established or ruled out using endosonography. Only patients with a first acute episode of pancreatitis were included. RESULTS: 213 patients (male: 55%; median age: 56 years) were prospectively included in 14 centres. Causes of acute pancreatitis were: biliary (62%), alcoholic (25%), other (13%). Delay between symptom-onset and admission was <48 h in 80%. Endosonography was the sole method establishing the diagnosis of biliary pancreatitis in 15% of patients. At univariate analysis, age, female sex, declared alcohol consumption, elevated aspartate and alanine transaminases on admission, gammaglutamyl transferase, alkaline phosphatase, total bilirubin, lipase, mean corpuscular volume were predictive of a biliary origin. Only age (p < 0.0001), sex (p < 0.0008) and alanine transaminase (p < 0.0004) remained significant at multivariate analysis. At age 50, the respective sensitivity and specificity were 73 and 65%. With an elevated alanine transaminase at 2 times the upper limit of normal range, the respective sensitivity and specificity were 74 and 84%. The probability of a biliary origin of acute pancreatitis could be estimated by the following formula: = 1/1 + exp(4.6967 - 0.0656 x age + 1.1208 x sex - 0.6909 x alanine transaminase). CONCLUSION: When endosonography is performed to confirm or exclude a biliary origin of acute pancreatitis, age, sex and alanine transaminase at admission are the only factors predictive of a biliary cause. 相似文献