Objective To investigate the effect of glucose metabolism alteration induced by alloxan intraventricular injection on learning and memory abilities of mice, and its role in the development of AD. Methods Mice were randomly divided into high-dose alloxan intraventricular injection group (n=7, 4 mg/kg) and low-dose alloxan intraventricular injection group (n=7, 1.5 mg/kg)and control group (n=7, physiological saline); intraventricular injection of alloxan, the O-GLcNAc transferase inhibitor, was performed in the high-dose and low-dose alloxan intraventricular injection groups to interfere the brain glucose metabolism. Morris water maze was used to detect the learning and memory abilities of mice. Western blotting and immunohistochemistry were used to analyze the alterations of phosphorylation and O-Glycosylation of neurofilament in mice brain induced by alloxan intraventricular injection. Results In the located navigation tests, the swimming time and distance to find the platform in the mice of alloxan administration were significantly increased as compared with those in the control group (P＜ 0.05); in space exploration experiments, compared with those in the control mice, the number of crossing the hidden platform was decreased and the initial angle of entry to water was increased in the mice of alloxan administration (P＜0.05). Western blotting and immunohistochemistry displayed that phosphorylation was obviously increased and the O-Glycosylation was significantly reduced in the cytoskletal neurofilament of the mice with alloxan administration as compared with those in the control group (P＜0.05), which was similar to the alteration of neurofilament's modification in AD brain. Conclusion The inventricular injection of alloxan could impair the learning and memory of mice, which might have a relation with the dysregulation of phosphorylation and O-Glycosylation in neurofilament caused by the impaired glucose metabolism, which is similar to the alteration of phosphorylation and O-Glycosylation in neurofilament in AD brain.

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.