Objective To investigate the sensation of the fingers innervated by the brachial plexus roots and provide the theoretic basis for diagnosis of a brachial plexus injury. Methods From June 2003 to January 2005，10 patients (8 males, 2 females; age,18-47 years) with complete brachial plexus avulsion were involved in this study, who underwent thecontralateral C7 nerve root transfer. The latency and amplitude of the sensory nerve actiopotential(SNAP) were record at the C5 T1 nerve roots when stimulation was given at the fingers.Results When the thumb and the index finger were stimulated and SNAP was recorded at all the roots of the brachial plexus in all the patients, we found that there was a higher amplitude and a shorter latency at the C5-7 roots than at the C8 and T1 roots(P＜0.05). When the middle finger was stimulated and SNAP was recorded at the C7,8 and T1 roots, we found that there was the highest amplitude and the shortest laency at the C7 root(P＜0.01). When the ring finger was stimulated and SNAP was recorded at the C7,8and T1 roots, we found that there was a higher amplitude and a shorter latency at the C8 and T1 roots than at the C7 root(P＜0.01). When the little finger was stimulated and SNAP was recorded at the C7,8and T1 roots, we found that there was the highest amplitude and the shortest latency at the T1 root(P＜0.01). ConclusionThe sense of the thumband the index finger is mainly nnervated by the C5-7 roots, the middle finger sense is mainly innervated by the C7 root, the ring finger sense is mainly innervated by the C8 and T1 roots, and the little finger sense is mainly innervated by the T1 root.
Objective To investigate the effect of extract of ginkgo biloba leaves (EGb50) on the prol iferation of SCs cultured in vitro. Methods The SCs were isolated from 3-day-old SD rats’ sciatic nerves by the method of enzyme gradationdigestion (n=20) and the purified 2nd passage of SCs were divided into 2 groups: the experimental group, in which SCs were cultured in FBS-DMEM medium with EGb50 (terminal concentration: 50 μg/mL); the control group, in which SCs were cultured in the FBS-DMEM medium without EGb50. The absorbance (A) value was detected by the 2, 3-bis- (2-methoxy-4-nitro-5- sulfophenyl)-2H-tetrazol ium-5-carboxanil ide (XTT) method 1, 3, 5, 7 and 9 days after culture, then the growth curves was drawn. Cell cycle was detected by flow cytometry (FCM). Disintegration per minute (DPM) of SCs was detected by the method of 3H-thymine nucleoside (3H-TdR) 2 and 3 days after culture and nerve growth factor (NGF) synthesis in SCs culture media was detected by ELISA method. Results Most SCs were spindle-shaped with a purity above 90%. XTT detection showed that A value of SCs in the control group was gradually increased 3 days after culture, reached the peak 5 days after culture and gradually decreased from then; the A value in the experimental group experienced the similar changes, but it was higher than that in the control group at each time point (P lt; 0.01). 3H-TdR showed that the DPM of the experimental group was 1 961.78 ± 231.13 and 4 601.51 ± 605.08 at 2 and 3 days after culture, while for the control group, the A value was 1 347.15 ± 121.57 and 3 740.42 ± 158.73 at the same time point, indicating a significant difference between two groups (P lt; 0.01). FCM observation indicated that the SCs prol iferation index of the experimental group and the control group was 18.6% ± 3.2% and 9.7% ± 2.9%, indicating a significant difference between two groups (P lt; 0.01). ELISA observation showed that the NGF concentration in the experimental and the control group was (0.065 6 ± 0.003 9) ng/mL and (0.038 6 ± 0.003 6) ng/mL, indicating a significant difference (P lt; 0.01). Conclusion EGb50 is capable of enhancing the prol iferation of SCs cultured in vitro, which may be one of the important mechanisms to promote peripheral nerve regeneration.