ObjectiveTo observe the hindlimb motor end-plate morphology and activity of acetyl cholinesterase (AChE) in different types of muscle fiber end-plate areas after spinal cord injury and spinal cord reconstruction tubes inducing spinal cord regeneration. Methods43 adult Wistar rats were randomly divided into spinal cord transected group at T8 (Cx group), spinal cord transected with transplantation of reconstruction tubes group (CxTp group) and control group (Co group). 2 weeks, 4 weeks, 3 months, 6 months and 12 months after operation, gastrocnemius, soleus and extensor digitorum longus were dissected respectively, and stained with gold chloride to observe the motor end-plate and stained with Karnovsky-Roots to detect AChE. ResultsIn Cx group, the end-plates degenerated since 3 months after operation, while the AChE activity declined. In CxTp group, end-plate structure and morphology were relatively stable and there were no signs of degeneration. ConclusionAfter spinal cord injury, motor end-plates undergo degeneration. The spinal cord reconstruction tubes graft can prevent end-plate degeneration and benefit for AChE reactivation and motor end-plate morphological and structural plasticity towards the direction of neurological rehabilitation.

Methods The maximum tolerated dose( MTD)of water and ethanol extracts of Radix millettiae speciosae were measured for the safety evaluation. Results Maximal tolerated dose( MTD)of water extract was higher than 1 000 g·kg-1 ,which equaled to 110 times the dose for human adults(60 kg). MTD of ethanol extract was higher than 1 700 g·kg-1 ,which equaled to 186 times the dose for human adults(60 kg). Conclusion Radix millettiae speciosae does not have obvious toxicity,thus its routine clinical dose is safe and feasible.

Objective To evaluate the safety of Solanumprocumbens by studying its acute toxicity to mice. Methods The dosage of 100% death ( Dm) and 100% survive ( Dn) were determined. Five groups were set between the dosage of Dm and Dn in a 1:0.8 ratio, and then were intragastrically administrated once at the dosage of 250,200,160,128,102.4 g·kg-1 respectively.Toxicity and mortality of mice after intragastricly administration of Solanumprocumbens were observed for 14 days continuously. Results After four hours of administration, there were death in each group except the lowest dosage group (102.4 g·kg-1).Number of death of the groups 250,200,160 and 128 g·kg-1 were 10,8,6 and 3 respectively.LD50 of Solanumprocumbens was 153. 02 g · kg-1 , the 95% confidence interval was ( 136. 55, 171. 47 ) g · kg-1 . Conclusion Solanumprocumbens has a certain toxicity.More attention should be payed to its toxicity for clinical rational drug use.

Objective:To compare the consistency and detection capability of seven 2019-nCoV nucleic acid detection kits, and provide reference for detection method selection of clinical laboratory and diagnosis of new coronavirus pneumonia.Methods:Two batches of pharyngeal swab samples were collected from tenpatients with confirmed infection of 2019-nCoV and 10 suspected patients with negative 2019-nCoV test results during January 29 to February 5, 2020 in Shenzhen Luohu People′s Hospital. Seven kinds of kits were labeled as ato g and used for nucleic acid detection respectively to evaluate the consistency of the test results of the clinical samples. A 2019-nCoV positive specimen was selected and diluted to 5-concentration gradient plates (Level-1 to 5) with RNase-free water. The positive detection rate and intra-batch repeatability of different brands of kits were compared.Results:The negative and positive coincidence rates of twenty clinical samples tested by six kinds of kits were 100%, and the positive and negative coincidence rate was 8/10 and 10/10 for the other kit, respectively. The results of intra-batch repeatability showed the CVs of viral loads tested by these seven kits were all less than 5%. In the concentration range of Level-1 to 3, the detection capability for open reading frame (ORF)1ab gene of Kit b,d and f was lower than Kit a,c,e and g, and the detection capability of kit e and g was the highest (14/15). The detection capability for N gene of Kit a (15/15) was higher than the other 5 kits. The comprehensive analysis of the detection capability for ORF1ab and N gene showedthat Kit d had the lowest detection capability (ORF1ab:40%,N:53%), and there was no significant difference in the detection capability of Kit a, b, c, e, and f.Conclusions:There was no significant difference in the accuracy and repeatability of the seven kits for positive samples with high viral loads, and the detection performance was good; but some kits had poor detection capability for weak positive samples. It is suggested that the weak positive samples should be rechecked by at least two manufacturers′ kits to ensure the accuracy of the results.