Résumé
Objective:To explore solutions to the "grey zone" of activated partial thromboplastin time (APTT) mixing study, and establish the clinical application pathway of it.Methods:Patients treated in West China Hospital of Sichuan University from January 1, 2018, to December 31, 2019, with a prolonged APTT were included in this study. The ROC curve was used to analyze the"cut-off"of different methods and explore solutions to the "grey zone" by combination of the 1∶1 and 4∶1 mixing study. Similar samples from January 1, 2020 to December 31, 2020 were included to verify the diagnostic efficiency of the clinical application pathway.Results:The traditional Rosner index criterion had a low diagnostic accuracy in differentiating factor deficiencies from inhibitors. A total of 49 cases (15%) in the establishment group and validation group were located in the "grey zone". The optimal cut-off value of the Rosner index in our 1∶1 mixing study for determining factor deficiency was 5.0%, and inhibitor was 9.1%. The sample between 5.0% and 9.0% needed 4∶1 mixing studies, which could significantly improve the detection sensitivity of inhibitors. The percentage of extended time after incubation-P (1∶1 mixing>10.8% and 4∶1 mixing>13.5%) was better than the traditional criterion mentioned by"consensus"in determining whether the inhibitor was time-dependent. The sensitivity, specificity, positive predictive value and negative predictive value of combined the 1∶1 and 4∶1 mixing study in differentiating factor deficiencies from inhibitors all attained more than 90%. Only 7% (3/43)of inhibitors were incorrectly classified into the factor deficiency group by the combination, which was 20.9% (9/43) by traditional criterion. The specificity for detecting time-dependent inhibitor was increased from 54.2% to 100%, and accuracy was increased from 63.3% to 97.4%.Conclusions:The combination of 1∶1 and 4∶1 mixing study can better resolve the "grey zone". The established clinical application pathway is beneficial for the further promotion and clinical application of APTT mixing study.
Résumé
@#Objective To investigate the effect of different administration methods of tranexamic acid on postoperative pulmonary inflammation response during cardiopulmonary bypass (CPB). Methods A total of 64 SD rats were included in the study. They were randomly divided into eight different groups. CPB model was established for the operation groups. The rats in the operation groups were given tranexamic acid at low (25 mg/kg), medium (50 mg/kg) or high (100 mg/kg) concentrations before or after the CPB. Blood cells count and coagulation function were assessed 1 hour after surgery. The concentration of interleukin (IL)-1β、IL-6 and tumor necrosis factor (TNF)-α in blood and lung lavage fluid were measured. The infiltration of inflammatory cells in lungs was observed by hematoxylin-eosin (HE) staining. Results The concentration of inflammatory cells in the operation groups was higher than that in the control group (P<0.05). The use of tranexamic acid inhibited the increase of IL-6 and TNF-α in whole blood and lung lavage fluid due to CPB (P<0.05), but there was no significant difference among the experimental groups (P>0.05). Tranexamic acid could reduce the exudation of inflammatory cells in the lungs. Conclusion The use of tranexamic acid can effectively reduce the release of inflammatory factors and reduce acute lung injury caused by CPB in rat models. But simply increasing the dose or changing the timing of administration is not more effective in reducing the intensity of the inflammatory response.
Résumé
Objective·To make clear the role of cerebral microbleeds (CMBs) for early cognitive impairment in small vessel disease (SVD). Methods·Fifty-seven consecutive SVD patients without dementia were strictly recruited. All participants were examined with a comprehensive battery of neuropsychological tests, SWI and DTI. According to the amount of CMBs, the patients were divided into CMBs group and non-CMBs group, or divided into multiple CMBs group (CMBs ≥ 3) and non-multiple CMBs group (CMBs<3). The mean diffusivity (MD) and fractional anisotropy (FA) in periventricular, central semiovale and subcortical white matter was analyzed with a region-of-interest method. Results·The score of multiple CMBs group in attention and memory function was significantly lower than that of the non-multiple CMBs group. Correlation analysis showed that the count of CMBs in the whole brain was significantly correlated with periventricular white matter MD, subcortical white matter MD, periventricular white matter FA and subcortical white matter FA. The count of CMBs in the whole brain adjusted by age, gender, education was significantly correlated with attention/executive function. After adjustment of subcortical/ periventricular white matter FA and MD and locations of CMBs they still had significant correlation. Conclusion·CMBs can reflect the degree of destruction of white matter integrity, and have independent effects on injury of brain parenchyma, resulting in early cognitive impairment. The research also suggests the role of CMBs in cognitive impairment may exist threshold value effect.