Comparability of the results of PT-INR with local MNPT and APTTR with MNAPTT on different coagulation analyzers in China

QCM-D providing new horizon in the domain of sensitivity range and information for haemostasis of human plasma

Monitoring of the haemostasis status is significant for proper therapeutic directions and decisions in surgery and innate coagulation disorders. In this regard, to gain a general overview of the plasmatic coagulation, prothrombin time (PT) tests are frequently combined with tests for activated partial thromboplastin time (aPTT). For aPTT we report for the first time that a QCM-D (Quartz Crystal Microbalances with Dissipation) based technique offers a better alternative to the standard coagulometer method in the perspective of range and information. We used heparin as anticoagulant to generate different coagulation times for human plasma. QCM-D astonishingly proved to be more sensitive and reliable than the standard coagulometer for aPTT range of upper limits of coagulation times. The established platform can monitor the fibrinogen concentration ranging from 1-6g/L (yielding R(2)=0.98 in calibration curves) along with aPTT from frequency and dissipation shifts together in a single set of measurements. Additionally the sensor layers have been tested for reusability, demonstrating no loss in sensor characteristics up to ten times measurements.

In vitro protection of adipose tissue-derived mesenchymal stem cells by erythropoietin

Mobilization of stem cells and their differentiation into cardiomyocytes are known to have protective effects after myocardial infarction. The integrity of transplanted mesenchymal stem cells for cardiac regeneration is dependent on cell-cell or cell-matrix interaction, which is adversely affected by reactive oxygen species in an ischemic environment. Treatment with erythropoietin was shown to protect human adipose tissue derived mesenchymal stem cells in an ischemic injury in vitro model. The analyses indicated that expression of erythropoietin receptors played a pivotal role in erythropoietin mediated cell survival. In this study, the anti-apoptotic effect of erythropoietin on stem cells was analyzed in apoptosis-induced human mesenchymal stem cells. Apoptosis was induced in cultured adult human adipose tissue derived mesenchymal stem cells by hydrogen peroxide. A group of cultured cells was also treated with recombinant human erythropoietin in a concentration of 50 ng mL(-1). The degree of apoptosis was analyzed by flow-cytometry and immunohistochemical staining for Caspase 3. The average percentages of apoptotic cells were significantly higher in H2O2-induced stem cells than in cells co-cultured with erythropoietin (63.03 ± 4.96% vs 29 ± 3.41%, p<0.01). We conclude that preconditioning with erythropoietin suppresses apoptosis of mesenchymal stem cells and enhances their survival.