A potent SARS-CoV-2 antibody neutralizes Omicron variant by disassembling the spike trimer

The continuous emergence of novel SARS-CoV-2 variants poses new challenges to the fight against the COVID-19 pandemic. The newly emerging Omicron strain caused serious immune escape and raised unprecedented concern all over the world. The development of antibody targeting conserved and universal epitope is urgently needed. A subset neutralizing antibody(nAbs) against COVID-19 from convalescent patients were isolated in our previous study. Here in this study, we investigated the accommodation of these nAbs to SARS-CoV-2 variants of concerns (VOCs), revealing that IgG 553-49 neutralizes pseudovirus of SARS-CoV-2 Omicron variant. In addition, we determined the cryo-EM structure of SARS-CoV-2 spike complexed with three antibodies targeting different epitopes, including 553-49, 553-15 and 553-60. Notably, 553-49 targets a novel conserved epitope and neutralizes virus by disassembling spike trimers. 553-15, an antibody that neutralizes all the other VOCs except omicron, cross-links two spike trimers to form trimer dimer, demonstrating that 553-15 neutralizes virus by steric hindrance and virion aggregation. These findings suggest the potential to develop 49 and other antibody targeting this highly conserved epitope as promising cocktail therapeutics reagent for COVID-19. ImportanceThe newly emergence of Omicron strain caused higher immune escape, raising unprecedented concerns about the effectiveness of antibody therapies and vaccines. In this study, we identified a SARS-CoV-2 Omicron neutralizing antibody 553-49, which neutralizes Omicron variant by targeting a completely conserved novel epitope. Besides, we revealed that IgG 553-15 neutralizes SARS-CoV-2 by crosslinking virions and 553-60 functions by blocking receptor binding. Comparison of different RBD epitopes revealed that the epitope of 553-49 is hidden in the S trimer and keeps high conservation during SARS-CoV-2 evolution, making 553-49 a promising therapeutics reagent to fight against the emerging Omicron and future variant of SARS-CoV-2.

Rapid analysis and identification of chemical components of ethanol extract from Mongolian medicine Sanzi san by HPLC-Q-Exactive-MS / 中国药房

OBJECTIVE To systematic ally stu dy the chemic al components of ethanol extract from Sanzi san ，and to provide reference for clarifying the pharmacodynamic material basis of the formulation. METHODS HPLC-Q-Exactive-MS technology was adopted. The determination was performed on Shim-pack GIST-HP C 18 column with mobile phase consisted of acetonitrile- 0.1％ formic acid aqueous solution for gradient elution at the flow rate of 1 mL/min. The column temperature was 40 ℃，and sample size was 10 μL. Mass spectrometry conditions included the electrospray spray ion source was used for detection in positive and negative ion detection modes. Full MS/dd-MS 2 detection mode was adopted ，the resolution of Full MS was 70 000 and the resolution of dd-MS2 was 17 500. The scanning range was m/z 110-1 200. The ion peaks were identified by comparing with the information of control substances ，literature references and self-built database. RESULTS A total of 64 components were identified in the ethanol extract of Mongolian medicine Sanzi san ， including 9 flavonoids，13 iridoids，14 organic acids ，18 tannins，3 triterpenes，3 amino acids and 4 fatty acids. CONCLUSIONS The ethanol extract of Mongolian medicine Sanzi san mainly include iridoids ，tannins and flavonoids ，which might be the pharmacodynamic material basis of Sanzi san.

Research on automatic removal of ocular artifacts from single channel electroencephalogram signals based on wavelet transform and ensemble empirical mode decomposition / 生物医学工程学杂志

The brain-computer interface (BCI) systems used in practical applications require as few electroencephalogram (EEG) acquisition channels as possible. However, when it is reduced to one channel, it is difficult to remove the electrooculogram (EOG) artifacts. Therefore, this paper proposed an EOG artifact removal algorithm based on wavelet transform and ensemble empirical mode decomposition. Firstly, the single channel EEG signal is subjected to wavelet transform, and the wavelet components which involve EOG artifact are decomposed by ensemble empirical mode decomposition. Then the predefined autocorrelation coefficient threshold is used to automatically select and remove the intrinsic modal functions which mainly composed of EOG components. And finally the 'clean' EEG signal is reconstructed. The comparative experiments on the simulation data and the real data show that the algorithm proposed in this paper solves the problem of automatic removal of EOG artifacts in single-channel EEG signals. It can effectively remove the EOG artifacts when causes less EEG distortion and has less algorithm complexity at the same time. It helps to promote the BCI technology out of the laboratory and toward commercial application.

Optimization of Ethanol Extraction Technology of Mongolian Medicine Naru- 3 / 中国药房

OBJECTIVE：To optim ize ethanol extraction technology of Mongolian medicine Naru- 3. METHODS ：The L 9（34） orthogonal design was used to optimize ethanol extraction technology of Mongolian medicine Naru- 3 with solid-liquid ratio ，ethanol volume fraction and extraction time as factors ，using comprehensive scores for the contents of benzoylaconitine ，benzoylneoaconitine， benzoylhypoaconitine，aconitine，neoaconitine，hypoaconitine，piperine and gallic acid as indexes. RESULTS ：The optimal ethanol extraction technology was that solid-liquid ratio of 1∶10（g/mL），ethanol volume fraction of 75％，extracting for 1.5 h. After 3 times of validation tests ，average contents of above 8 components in ethanol extract from Naru- 3 were 1.69，1.48，14.69，0.28， 0.05，0.08，26.01，17.33 mg/g（RSDs were 0-4.96％，n＝3），respectively. Average comprehensive score was 19.03（RSD＝1.42％， n＝3）. CONCLUSIONS ：The optimal ethanol extraction technology of Mongolian medicine Naru- 3 is stable and feasible.

A research for single trial detection of error related negativity / 生物医学工程学杂志

Error related negativity (ERN) is generated in frontal and central cortical regions when individuals perceive errors. Because ERN has low signal-to-noise ratio and large individual difference, it is difficult for single trial ERN recognition. In current study, the optimized electroencephalograph (EEG) channels were selected based on the brain topography of ERN activity and ERN offline recognition rate, and the optimized EEG time segments were selected based on the ERN offline recognition rate, then the low frequency time domain and high frequency time-frequency domain features were analyzed based on wavelet transform, after which the ERN single detection algorithm was proposed based on the above procedures. Finally, we achieved average recognition rate of 72.0% ± 9.6% in 10 subjects by using the sample points feature in 0~3.9 Hz and the power and variance features in 3.9~15.6 Hz from the EEG segments of 200~600 ms on the selected 6 channels. Our work has the potential to help the error command real-time correction technique in the application of online brain-computer interface system.

Clinical Retrospective Dermatology Study on 169 Cases of Chronic Actinic Dermatitis / 昆明医科大学学报

Objective To investigate clinical features of chronic actinic dermatitis (CAD) in Kunming of Yunnan Province.Methods From October 2008 to October 2013,CAD in-patients in our hospital were selected and their general conditions,outcomes of photo-sensitive test and photo-patch test were analyzed in details.Results (1) Among 169 CAD patients,gender ratio (male:female) was 8.9:1.The lesions were mainly distributed on the exposed areas.(2) Photo-sensitive tests of 93 patients showed that the average value of UVA-MPPDwas 7.39 JPcm2 and that of UVB-MED was 20.91 mJPcm2.(3) The results of photo-patch test in 83 patients showed that 48 patients (67.8％) had positive reactions in patch test,and the most common contactant was balsam peru.Fifty-eight patients (69.9％) had positive reactions in photo-patch test indicating that the most common contactant in photo-patch test was balsam peru.Conclusions CAD appears mostly in the middle aged and the aged males and the lesions are mainly distributed on exposed areas.The most common contactants in photo-patch test are balsam peru and perfumed compounds.

Role of polycyclic aromatic hydrocarbons and aryl hydrocarbon receptor in the development of tumor / 中国生化药物杂志

Polycyclic aromatic hydrocarbons ( PAHs) are ubiquitous environmental pollutants, whose carcinogenicity is determinated.The mechanism of their carcinogenicity: PAHs are able to combine with aryl hydrocarbon hydrocarbon receptor ( AhR ) , resulting in some toxicity and carcinogenicity.AhR is a ligand-dependent activation transcription factor, which is activated by a large variety of ligands, regulating the expression of a series of gene involved in metabolism, and participating in important biological processes, such as singal transduction, cell proliferation,differentiation and apoptosis,and so on.Besides, it's closely related with the tumor development.Thus, it will provide a new approach for cancer prevention and treatment to study the role of PAHs and AhR in the development of tumor.

Monitoring depth of anesthesia and effect analysis in primary visual cortex of rats based on complexity of local field potential / 生物医学工程学杂志

In the present study carried out in our laboratory, we recorded local field potential (LFP) signals in primary visual cortex (V1 area) of rats during the anesthesia process in the electrophysiological experiments of invasive microelectrode array implant, and obtained time evolutions of complexity measure Lempel-ziv complexity (LZC) by nonlinear dynamic analysis method. Combined with judgment criterion of tail flick latency to thermal stimulus and heart rate, the visual stimulation experiments are carried out to verify the reliability of anesthetized states by complexity analysis. The experimental results demonstrated that the time varying complexity measures LZC of LFP signals of different channels were similar to each other in the anesthesia process. In the same anesthesia state, the difference of complexity measure LZC between neuronal responses before and after visual stimulation was not significant. However, the complexity LZC in different anesthesia depths had statistical significances. Furthermore, complexity threshold value represented the depth of anesthesia was determined using optimization method. The reliability and accuracy of monitoring the depth of anesthesia using complexity measure LZC of LFP were all high. It provided an effective method of realtime monitoring depth of anesthesia for craniotomy patients in clinical operation.

Study on the Quality Standard of Xiaoer Shengxue Granules / 中国中医药信息杂志

Objective To establish a quality standard for Xiaoer Shengxue granules. Method SHU-Dihuang, yam, Chinese data in Xiaoer Shengxue granules were identified by TLC. Ferrous sulfate in the granule was determined by UV with wavelength at 509 nm. Results SHU-Dihuang, yam, Chinese data could be detected by TLC. Ferrous sulfate showed a good linear relationship at the range of 0.50～2.50 mg/mL, r=0.999 9. The average recovery was 101.3% and RSD was 1.48% (n=5). Conclusion The method is available with a good reproducibility and can be used for the quality control of Xiaoer Shengxue granule.