Objective To investigate the possible causes of the different diagnostic sensitivity of voluntary single fiber electromyography (SFEMG) and repetitive nerve stimulation(RNS) in patients with myasthenia gravis (MG). Methods The voluntary SFEMG and RNS at low rates were recorded successively from the same extensor digitorum communis (EDC) muscle on the same day in 67 patients with MG. Results The diagnostic sensitivity of SFEMG and RNS was 92.5% and 50.7%, respectively, with the former statistically significantly higher than the later. The percentage of decrement of RNS was positively correlated with 3 SFEMG parameters, i.e. the mean jitter, percentage of abnormal pairs of potential and percentage of impulse blocking. Among the 34 cases with significant decrement on RNS, 2 had no impulse blocking and the maximum decrement reached 62%, while 33 cases with normal RNS had up to 58% of impulse blocking. Conclusion The voluntary SFEMG was more sensitive than RNS in diagnosing MG even in the same muscle. The blocking phenomenon observed in voluntary SFEMG was not completely corresponding to the decrement in RNS.The possible explanations were partly because that RNS recorded the total muscle fibers response in surface of the muscle and SFEMG examined the increasing or blocking at individual motor end-plates, and partly because that the voluntary SFEMG and RNS might explored endplates belonging to different motor units.

Objective To investigate the effectiveness and safety of low-intensity warfarin anticoagulation in over 80-year-old patients with nonvascular atrial fibrillation (NVAF). Methods The 180 NVAF patients aged over 80 years were randomly assigned into 2 groups: 90 patients in lowintensity warfarin anticoagulation group (target value of INR 1.6-2.0), the other 90 patients in standard-intensity warfarin anticoagulation group (target value of INR 2. 0-3.0). All patients were followed up in outpatient-department for one year. Main outcome measures included the incidence rates of bleeding and thromboembolic events, and secondary outcome measures included the warfarin dosage and times of INR＞3.0. Results The incidence rate of thromboembolic events was 4.4% (4/90) in low-intensity group and 3.3% (3/90) in standard-intensity group with no statistically significant difference between these two groups (P＞0. 05). However, the incidence rate of hemorrhage was significantly lower in low-intensity group than in standard-intensity group [5.6% (5/90) vs. 16.7%(15/90), P＜0. 05]. Meanwhile the warfarin dosage was significantly lower in low-intensity group than in standard-intensity group [(1. 55±0. 63) mg vs. (2.31±0.57) mg, P＜0.05]. The times of INR＞3.0 were less in low-intensity group than in standard-intensity group (P＜0. 05). Conclusions Therapy with low-intensity warfarin anticoagulation in NVAF patients aged over 80 years may be equally effective as, but safer than that with standard-intensity warfarin.

Objective To observe the changes of islet cell apoptosis and oxidation-antioxidation before the transplantation, and to explore the pathways of islet protection. Methods Fifteen human pancreases were perfused with the Hanks solution containing collagenase, then digested and isolated. During the procedure, islet cell apoptosis was detected by TUNEL, SOD and MDA in the pancreas were measured by colorimetric method, and the morphologic changes were observed by H-E staining and dithizone staining. Results In the procedure of human islet isolation, especially in the stage of digestion, the apoptosis of human islet cells occurred. In the stages of perfusion and digestion, the MDA contents reached the high levels (6. 18 ± 2. 38 and 9. 21 ± 2. 75 umol/mg protein respectively),and the structures of the islets and tissues around the islets were damaged. Conclusion In the stages of perfusion and digestion, apoptosis of islet cells can be caused by oxidation. It suggests that antioxidation is a pathway for protection of islets before transplantation.