Objective To establish the method of thin layer chromatography (TLC) for identification and quantitative determination of Shipi Xiaoshui gel plaster. Methods TLC was adopted to qualitatively identify astragalus radix, plantaginis semen, curcumae rhizome, cinnamomi ramulus, polyporus umbellatus and akebia quinata. UPLC-MS was used to determine the content of astragaloside Ⅳ. Results TLC spots were clear and well-separated; RSDs of precision, reproducibility and stability tests were all lower than 3%, the linear range of astragaloside Ⅳ was 2.75-33 μg/ml (r=0.999 9, n=6), and the average recovery was 100.49% (RSD=1.98%, n=6). Conclusion The established method in this study is accurate, reliable and specific, which could be used for the quality control of Shipi Xiaoshui gel plaster.

Antibiotics are a category of chemical compounds used to treat bacterial infections and are widely applied in cultivation,animal husbandry,aquaculture,and pharmacy.Currently,residual antibiotics and their metabolites pose a potential risk of allergic reactions,bacterial resistance,and increased cancer incidence.Residual antibiotics and the resulting bacterial antibiotic resistance have been recognized as a global challenge that has attracted increasing attention.Therefore,monitoring antibiotics is a critical way to limit the ecological risks from antibiotic pollution.Accordingly,it is desirable to devise new analytical platforms to achieve efficient antibiotic detection with excellent sensitivity and specificity.Quantum dots(QDs)are regarded as an ideal material for use in the development of antibiotic detection biosensors.In this review,we characterize different types of QDs,such as silicon,chalcogenide,carbon,and other doped QDs,and summarize the trends in QD-based antibiotic detection.QD-based sensing applications are classified according to their recognition strategies,including molecularly imprinted polymers(MIPs),aptamers,and immunosensors.We discuss the advantages of QD-derived antibiotic sensors,including low cost,good sensitivity,excellent stability,and fast response,and illustrate the current challenges in this field.

ObjectiveTo explore the prevalence rate and related risk factors of anxiety， depression and insomnia symptoms in close contacts of COVID-19 patients undergoing centralized quarantine and observation， so as to provide references for follow-up targeted psychological crisis intervention. MethodsFrom February 6 to 8， 2020， a total of 136 close contacts at designated quarantine sites in four districts and counties of Ya'an city were enrolled， and assessed using the general information questionnaire， Hospital Anxiety and Depression Scale （HAD） and Insomnia Severity Index （ISI）. ResultsA total of 26 quarantined individuals （19.12%） had various degrees of anxiety， depression or insomnia， including 16 cases （11.76%） with anxiety， 9 cases （6.62%） with depression and 16 cases （11.76%） with insomnia. Correlation analysis showed that HAD （A） score was positively correlated with HAD （D） score （r=0.642， P<0.01）. HAD （A） score was positively correlated with ISI score （r=0.590， P<0.01）. HAD （D） score was positively correlated with ISI score （r=0.329， P<0.01）. Multivariate Logistic regression analysis showed that the risk factor of anxiety was the first week of isolation （OR=3.290， P<0.05）， meantime， the risk factors of insomnia included the old age （OR=7.990， P<0.05） and the first week of isolation （OR=4.659， P<0.05）. ConclusionThe close contacts of COVID-19 infections undergoing centralized quarantine and observation in Ya’an have high prevalence rate of anxiety and insomnia， and the symptoms are most severe during the first week of quarantine.

Objective: To investigate the relationship between cervical curvature (CC) and spinal drift distance after laminectomy with lateral mass screw fixation and the influence on the operative effect. Methods: From October 2016 to December 2017, a total of 85 patients with cervical spondylotic myelopathy (CSM) underwent laminectomy with lateral mass screw fixation in handan central hospital, and 78 patients were followed up completely.After the operation, according to the Harrison method, they were divided into 2 groups(Group A (43 cases, 0°≤CC≤16.5°); Group B (35 cases, CC>16.5°)). The spinal drift distance, nerve recovery, axial symptoms and C5 palsy in the groups were recorded and analyzed. Results: The CC was 8.5°±3.8° in group A and 19.6°±3.0° in group B (t=14.071, P=0.000). The laminectomy width in group A was (22.1±1.7) mm, in group B was (21.8±1.5) mm, the difference between the two groups was not statistically significant (P>0.05). The distance of spinal cord backward movement was (1.7±0.4) mm in group A and (3.2±0.7) mm in group B. There was significant difference between the two groups (t=11.879, P<0.001). At the end of one year, the improvement rates of nerve function in the two groups were (63.3±13.1)% and (65.1±13.9)% respectively, there was no significant difference between the two groups (t=0.587, P=0.559). The VAS score of group A was (5.2±1.3) at one week and (3.5±0.6) at one month after operation, and that of group B was (3.8±0.8) and (2.4±0.4) respectively.There were statistically significant differences between groups at different time points (t=5.567, P<0.001; t=9.289, P<0.001). The incidence of C5 paralysis was 7.0% (3/43) in group A and 11.4% (4/35) in group B. There was no significant difference between the two groups (P>0.05). Conclusion The greater the curvature of cervical spine is, the more fully the spinal cord moves backward.The loss of curvature of cervical spine is related to the occurrence of axial symptoms.The curvature of cervical spine is not related to the recovery of nerve function and the occurrence of C5 nerve paralysis.

DNA assembly is the core technology of synthetic biology. With the development of synthetic biology, researchers have developed different DNA assembly technologies that rely on DNA polymerase or DNA ligase, and also have developed some non-enzyme-dependent DNA assembly techniques to facilitate the automation of DNA assembly. The assembly of large fragments of DNA from a few hundred kb to Mb is mostly dependent on microbial recombination. In this paper, the three types of DNA assembly technologies, including enzyme-dependent, non-enzymatic and in vivo homologous recombination, are reviewed.
DNA ; Synthetic Biology

BACKGROUND: The biomechanics of cervical spine is complicated. It is an important way to select the appropriate biomechanical model and research method so as to explore the diagnosis and evaluation mechanism of cervical spine injury and prognosis judgement.OBJECTIVE: To discuss the alternation of cervical biomechanics after the degeneration of cervical disc and the influence of degeneration on cervical stability.METHODS: (1) A three-dimensional finite element model of cervical spine was established from the CT scan images of cervical spine of a healthy male volunteer, Solid-Works2015, HyperMesh and ANSYS11.0. We created a cervical three-dimensional finite element model. To simulate the degenerative disc by modified the mechanical characters and height of the disc model, we observed the biomechanics of the impact on the cervical spine (the range and the stress on intervertabral disc).RESULTS AND CONCLUSION: (1) The entire model with a total of 97705 nodes and 372896 elements. Ligament and joint capsule were also constructed. Face to face contact element was used in the facet joint, with complete structure and high accuracy of measurement of spatial structure. (2) The range of motion of cervical spine increased during degeneration compared with normal cervical segments (P < 0.05). (3) Intervertebral disc degeneration caused angle increase at disc and motion segment. Osteophyte formed on vertebral edge. Intervertebral disc degeneration caused cervical instability. Simultaneously, instability increased the disc degeneration.

Chromosomal integration of heterologous genes or pathways is preferred over the use of episomal plasmids for its inherently stability and thus more desirable in the industrial setting. However, the position of integration of heterologous genes in the genome influences the expression levels. In combination of high throughput transformation of the Yeast Knock-out Collection (YKO) and FACS analysis, the position effect on heterologous reporter gene gfp was identified across the whole genome in yeast. In total 428 high-expressed sites and 444 low-expressed sites were spotted, providing massive data to analyze patterns and reasons for region dependency of gene expression on the genome-wide scale.
Gene Expression Regulation, Fungal ; Gene Knock-In Techniques ; Genes, Reporter ; Genome, Fungal ; Saccharomyces cerevisiae ; genetics

Objective:To review the chemical and pharmacological activities of Codonopsis lanceolata in order to provide reference for the further development of C. lanceolata. Methods:The related literatures at home and abroad in the past 40 years were reviewed and analyzed, and then the chemical components and pharmacological actions of C. lanceolata were summarized. Results: The major chemical constiturents in C. lanceolata were terpenoids, alkaloids, phenylethanoid glycoside and flavonoids. The pharmacological ac-tivities were antioxidation, anti-inflammatory, anti-tumor, antiplatelet aggregation, hypoglycemic and hypolipidemic effects, etc. Con-clusion:The review provides reference for the further development and comprehensive utilization of C. lanceolata. The development of relevant safe and effective agents is still needed, and at present, the definition of mechanism and the extension of clinical application remain as the primary tasks of the exploration of C. lanceolata.

OBJECTIVETo study the regularity of the passive tensile of the masticatory muscles and ligaments by Twin-Block appliance under various bite reconstruction, and to provide some biomechanical references for the clinical use and improvement of Twin-Block appliance.

METHODS"Temporomandibular joint, mandible and Twin-Block appliance" model was set up by the three dimensional finite element method, and the related masticatory muscles and ligaments were added on it. Seven experimental groups were designed according to the clinical and research, the occlusal inclined plate's angles of Twin-Block appliance were 40 degrees, 45 degrees, 50 degrees, 55 degrees, 60 degrees, 65 degrees and 70 degrees. The passive tensile in the masticatory muscles and ligaments were analyzed by the computer.

RESULTSUnder various experimental groups, the passive tensile in the anterior deep masseter (AM), the posterior deep masseter (PM), the anterior temporalis (AT), the posterior temporalis (PT), the stylomandibular ligament and sphenomandibular ligament improved with the increased slant angles of occlusal guide. The maximum value of the passive tensile was 82.57 N, the minimum value was 0.07 N.

CONCLUSION1) In various experimental groups, AT, AM, PM, PT, stylomandibular ligament and sphenomandibular ligament are subject to passive tension force in the process of Twin-Block appliance guiding the mandibular forward and play the important role on the remodeling of the mandible. 2)All groups of occlusal inclined plate's angle are in physiologically tolerable range and can be used in clinic.

Objective To study a correlativity of amplitude of low frequency fluctuation change of restingstate brain activity and aphasia quotient in aphasia patients after stroke and investigate recovery and mechanism of the aphasia.Methods Adopting amplitude of low-frequency fluctuation (ALFF) in blood oxygenation level dependent functional MRI(BOLD-fMRI) and Siemens version 3.0T MR Scanner was used to obtain 12 aphasia patients and 20 normal volunteers of fMRI data.The fMRI data were processed with the software of DPARSF and analyzed by ALFF,and group analysis was performed with two sample t-test by REST software to obtain increased and decreased ALFF map.Brain regions,in which,ALFF of aphasia group was lower than that of normal control group,were done correlation analysis with aphasia quotient.Results As compared with those in normal subjects,the regions showing decreased ALFF in aphasia patients were distributed in left middle temporal gyrus,left medial prefrontal gyrus,right cerebellum,which were positively correlated with aphasia quotient (r Roi1 =0.48,r Roi2 =0.36,r Roi3 =0.28,respectively);while the regions showing increased ALFF covered left occipital lobe,precentral gyrus,insula,right precuneus.Conclusion As compared with those in normal subjects,the regions positively correlated with aphasia quotient show decreased ALFF in aphasia patients,which are one of the mechanisms of aphasia.The regions increased ALFF in aphasia patients may participate in language function of recovery.