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Objective To analyze the status of quality indicators(QI) on specimen acceptability and establish preliminary qual ity specification.Methods Web based External Quality Assessment system was used to collect data of laboratories partici pated in "Medical quality control indicators in clinical laboratory" from 2015 to 2017,including once in 2015 and 2017 and twice in 2016.Rate and sigma scales were used to evaluate incorrect sample type,incorrect sample container,incorrect fill level and anticoagulant sample clotted.The 25th percentile (P25) and 75th percentile (P75) of the distribution of each QI were employed to establish the high,medium and low specification.Results 5 346,7 593,5 950 and 6 874 laboratories sub mitted the survey results respectively.The P50 of biochemistry (except incorrect fill level),immunology and microbiology reach to 6σ.The P50 of clinical laboratory is 4 to 6σ except for incorrect sample container.There is no significant change of the continuous survey results.Based on results in 2017 to establish the quality specification,the P25 and P75 of the four QIs is 0 and 0.084 4 ％,0 and 0.047 6 ％,0 and 0.114 2 ％,0 and 0.078 4 ％,respectively.Conclusion According to the results of the survey,most laboratories had a faire performance in biochemistry,immunology and microbiology,and clinical laboratory needs to be strengthened.Laboratories should strengthen the laboratory information system construction to ensure the actual and reliable data collection,and make a long time monitoring to achieve a better quality.
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Brain microvascular endothelial cells form the interface between nervous tissue and circulating blood, and regulate central nervous system homeostasis. Brain microvascular endothelial cells differ from peripheral endothelial cells with regards expression of specific ion transporters and receptors, and contain fewer fenestrations and pinocytotic vesicles. Brain microvascular endothelial cells also synthesize several factors that influence blood vessel function. This review describes the morphological characteristics and functions of brain microvascular endothelial cells, and summarizes current knowledge regarding changes in brain microvascular endothelial cells during stroke progression and therapies. Future studies should focus on identifying mechanisms underlying such changes and developing possible neuroprotective therapeutic interventions.
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OBJECTIVE: To investigate the protective effect of ferulic acid on neuronal apoptosis of the spinal cord after aortic blood cross-clamping and its mechanism in rabbits. METHODS: Twenty-four rabbits were randomly divided into sham operation group, ischemia/reperfusion (I/R) injury group and ferulic acid group. Spinal cord I/R injury model was replicated by clamping blood of the infrarenal aorta for 40 minutes followed reperfusion for 7 days. Ferulic acid 50 mg/kg was injected 15 minutes before aortic clamping in ferulic acid group. The aorta was not clamped in sham operation group. Contents of malondialdehyde (MDA) and superoxide dismutase (SOD) in plasma were assayed at 10 minutes before clamping (C-10), before removal of occlusion (C40), at 60 minutes (R60) and on the 7 th day (R7d) after reperfusion. Apoptosis of neurones of spinal cord and the expressions of Bax and Bcl-2 protein were assayed by immunohistochemical technique. Neurologic function score of hind limb was observed after operation. RESULTS: (1)The activity of MDA after I/R in I/R injury group was increased significantly compared with those before clamping and those in sham operation group (P<0.05 or P<0.01). The activity of MDA in ferulic acid group was significantly higher than that at C-10 (P<0.05), while significantly lower than those in I/R injury group at any time point (P<0.05 or P<0.01), but showed no significant difference compared with sham operation group. Changes in SOD activities were opposite to that of MDA. (2)The expression of Bax protein in I/R injury group was increased significantly (P<0.05), but the expression of Bcl-2 protein was decreased significantly compared with that in sham operation group (P<0.01). In ferulic acid group, the expression of Bax protein was significantly lower than that in I/R injury group and higher than that in sham operation group (P<0.01 and P<0.05), and the expression of Bcl-2 protein was higher than those in I/R injury group and sham operation group (both P<0.01). (3)The index of neuronal apoptosis in I/R injury group was significantly higher than that in sham operation group (P<0.01), and that in ferulic acid group was much lower than that in I/R injury group, but higher than sham operation group (P<0.01 and P<0.05). (4)The degree of paralysis in ferulic acid group was significantly lower than that in I/R injury group, and a higher neurologic score was observed (both P<0.01). CONCLUSION: Ferulic acid can reduce the spinal cord neuronal apoptosis as a result of aortic occlusion in rabbits. The possible mechanism is that it decreases protein expression of Bax, increases that of Bcl-2 and enhances antioxidation.
