Objective:To evaluate the impact of sample pooling strategy on 2019-nCoV RNA detection results.Methods:Ten negative swabs were stored in 6 ml virus transport medium, mixed thoroughly and diluted 1∶2 and 1∶10. Inactivated 2019-nCoV culture medium was added to simulate pooling samples: 10 pooling samples, 5 pooling samples and 1 swab sample. Extraction and amplification were made using three nucleic acid extraction reagents a, b, and c with different extraction methods and systems, as well as five 2019-nCoV detection reagents A-E with various template loading volumes and sensitivities respectively.Results:For the same sample, the Ct values of extracted templates a were 2.10±0.47 and 3.46±0.62 earlier than extracted templates b and c. For samples with identical amplifying, the Ct valves of N and ORF1ab gene of A reagent were 1.16±0.48 and 2.36±0.54 earlier than that of reagent B. Adding nucleic acid of 10 negative swabs to the amplification system lagged the Ct values of reagent A by about 1.36±0.32 Ct, while Ct values of reagent B were not affected. Extracted by regent a, a lag of 1.66±0.39 Ct on average was observed in C, D, and E reagents in detecting pooling samples of ten swabs as compared with one swab sample. When extracting 400 copies/ml pooling samples of ten swabs by reagent a, N gene could be detected by reagents C and E, but not by reagent D.Conclusion:Large amount of extraneous DNA is introduced by sample pooling, which could interfere the effiency of extraction and amplification. Strategies of using extraction reagents with large loading volume and high effiency, together with amplification reagents with large template volume and low limit of detection are helpful for ensuring detection sensitivity of pooling samples, and greatly reducing the risk of false negative results.

Objective To compare the clinical effects of palpation, ultrasound and electromyography (EMG) guided injection of botuli-num toxin type A (BTX-A) on spastic equinovarus in stroke patients. Methods Stroke patients with equinovarus were randomly assigned to palpation-guided group (n=19), ultrasound-guided group (n=21) and EMG-guided group (n=19). All of the patients received injection of BTX-A 300 U in gastrocnemius, soleus and tibialis posterior, guided in their own ways. They were measured with modified Ashworth Scale (MAS), Physician Rating Scale (PRS), speed of gait, passive range of motion (PROM) of ankle dorsiflexion and eversion before and 2 weeks, 4 weeks, 8 weeks, and 12 weeks after injection. Results Compared with the baseline, all the indexes significantly improved after in-jection in all the groups (P<0.05). Compared with the EMG-guided group, the ultrasound-guided group improved significantly MAS at 4 weeks, PROM of ankle eversion at 4 and 12 weeks (P=0.046, P=0.008, P=0.038). Compared with the palpation-guided group, the ultra-sound-guided group improved significantly in MAS (P=0.015), PRS (P=0.01), PROM of ankle dorsiflexion and eversion (P=0.003, P=0.011) at 4 weeks, in MAS (P=0.002) and PROM of ankle dorsiflexion (P=0.022) at 8 weeks, in MAS (P=0.011) and PROM of ankle ever-sion (P=0.018) at 12 weeks. Compared with the palpation-guided group, the EMG-guided group improved significantly in PRS at 4weeks, PROM of ankle dorsiflexion at 4 and 8 weeks (P=0.048, P=0.08, P=0.026). There was no significantly difference in the variations with the time among 3 groups. Conclusion The correction of equinovarus in stroke patients can be obtained by BTX-A injection with any type of guidance technique. Ultrasound-guided technique is considered a valid alternative, which has a slight advantage over EMG-guided tech-nique. Both the EMG-and ultrasound-guided techniques obtained superior results to palpation-guided technique.

Objective The aim of this study was to analyze the disease burden of cirrhosis and other chronic liver diseases caused by hepatitis B in China,from 1990 to 2016,and to provide evidence for the development of related strategies.Methods Data were collected from the results of the Global Burden of Disease Study 2016 (GBD2016).We analyzed the current epidemiological patterns by calculating the prevalence,mortality,and disability adjusted life year (DALY) of cirrhosis and other chronic liver diseases,caused by hepatitis B during 1990 and 2016 in China.Results Compared with data from 1990,the number of patients and deaths with cirrhosis and other chronic liver diseases caused by hepatitis B in 2016 increased by 79.6％ and 2.4％,respectively.The prevalence increased by 49.2％,higher (50.3％) in males than that (42.3％) in females.Compared with other age groups,the increase (33.2％) of prevalence appeared the fastest,in the 15-49 age group.In males,the number of deaths and DALYs increased by 13.6％ and 2.2％,respectively.In 2016,the five top provinces on age-standardized DALY rates,appeared as Qinghai (314.6 per 100 000),Guizhou (303.1 per 100 000),Yunnan (262.4 per 100 000),Guangxi Zhuang Autonomous Region (239.6 per 100 000) and Taiwan (227.2 per 100 000).Conclusions From 1990 to 2016,the prevalence rates of hepatitis B related cirrhosis and other chronic liver diseases showed an upward trend,particularly in males and in people aged 15 to 49 years old,in China.However,the disease burden of different provinces was unevenly distributed.Based on our findings,we suggested that strategies that related to prevention and management of hepatitis B caused cirrhosis and other chronic liver diseases should be paid more attention to.