Preparation of antibacterial microfibre

Three different kinds of antibacterial microfibres (270D, 300D and 330D) have been developed by adding 2-4 wt % nano silver masterbatch in the melt spinning process. The mechanical properties, silver content and morphology have been examined with tensile tester, inductively coupled plasma-optical emission spectrometer and scanning electron microscope respectively. Their antibacterial abilities are also studied with KS K 0693:2011. The results show that the added nano-particles have little influence on mechanical properties of antibacterial microfibres and their max strain and tenacity are similar to that of common manmade fibre. The fineness of the 270D, 300D and 330D samples are found to be 0.23, 0.26 and 0.30 den, and the corresponding added silver contents are 265.5, 231 and 259 ppm respectively. It is also observed that all samples bacteriostatic reduction rates are about 99.9% for both Staphylococcus aureus and Klebsiella pneumonia before washing. But after washing, it drops to 65.4%/75%, 91.9%/97.7% and 94.8%/99.9% respectively for both the bacteria in case of 270D, 300D and 330D samples. It is concluded that 300D and 330D microfibre samples have good antibacterial ability before and after washing

Analysis of tumor-related features of non-small cell lung cancer based on TCR repertoire workflow

Objective·To explore the immune-related characteristics of non-small cell lung cancer (NSCLC), discover potential tumor markers in V-J genes, and lay the foundation for establishing a TCR-antigen recognition prediction model.Methods·A total of 704 NSCLC samples were collected to establish a comprehensive T-cell receptor (TCR) repertoire analysis workflow. The upstream analysis included steps such as raw data processing, quality control, filtering, TCR sequence identification, and extraction. The downstream analysis included repertoire clone distribution, clone typing, V-J gene sharing, CDR3 distribution characteristics, and clone tracking. The sample clone distribution was analyzed by using indices such as Shannon-Weiner index and Chao1 index. Clone typing was performed based on the number of clone amplifications to explore differences among different types. The degree of V-J gene segment sharing was analyzed, and the sharing of low-frequency clone types was determined through clone amplification weight analysis of V-J genes by using two samples of papillary thyroid carcinoma. Finally, analysis of the distribution characteristics of V genes and high-frequency clone type CDR3, and clone tracking analysis were conducted to monitor changes in tumor immune clone frequencies before and after analysis, aiming to identify potential tumor markers.Results·① Significant differences were observed in clone distribution and clone typing among different NSCLC tissues, as well as among different ages and genders. ② Specific highly-shared V-J genes were identified in the analysis of V-J gene sharing, and non-normal distribution of high-clone V genes and amino acid high-frequency clone types were found in the CDR3 distribution analysis. ③ In the analysis of high-frequency clone type clone tracking, highly expressed or newly expressed high-frequency clone types were observed in NSCLC, suggesting that these clone types could serve as potential tumor-associated antigens or bind with CDR3 reference sequences of new antigens. ④ It was found that the expression frequency of TRBJ2-5 gene, originally low-expressed, significantly increased, indicating its potential role as a key low-frequency gene in tumor immune response.Conclusion·The TRAV21 and TRBV6.5 genes show high clone amplification in NSCLC and could serve as potential tumor biomarkers

Verification of the formulation and efficacy of Danggui Buxue Tang (a decoction of Radix Astragali and Radix Angelicae Sinensis): an exemplifying systematic approach to revealing the complexity of Chinese herbal medicine formulae

This article exemplifies a systematic approach to revealing the complexity of Chinese herbal medicine formulae through three levels of scientific research: standardization of herbs, verification of ancient formulae and mechanism studies. We use Danggui Buxue Tang (DBT) as an example for this approach. Among thousands of traditional Chinese medicine herbal formulae, almost all of which consist of multiple herbs, DBT is one of the simplest. Containing only two herbs, namely Radix Astragali (RA) and Radix Angelicae Sinensis (RAS), DBT is traditionally used to treat ailments in women. The weight ratio of RA to RAS in DBT was prescribed to be 5:1 as early as in 1247 AD. In addition to advanced chemical analysis of herbal constituents, DNA genotyping techniques have been developed for reliable standardization of RA and RAS. Chemical evaluation shows that main active constituents in DBT, including astragaloside IV, calycosin, formononetin and ferulic acid, were most abundant after extraction at the RA to RAS ratio of 5:1, whereas other tested RA to RAS ratios only gave sub-optimal levels of the active constituents. Biological evaluation indicates that bioactivities of DBT, e.g. immuno-modulatory, oesteotropic and estrogenic effects are also best exerted at the RA to RAS ratio of 5:1. Correlation analysis demonstrates statistically significant relationship between the tested chemical constituents and tested bioactivities. Up- and down-regulation of expression of some genes as potential biomarkers has been detected by using gene chip technology. This systematic approach on the basis of herbal standardization, chemical and biological verification and mechanism studies, as exemplified in this article, will be useful to reveal the complexity of not only DBT but also other Chinese medicine herbal formulae

A broadly reactive antibody targeting the N-terminal domain of SARS-CoV-2 spike confers Fc-mediated protection

Most neutralizing anti-SARS-CoV-2 monoclonal antibodies (mAbs) target the receptor binding domain (RBD) of the spike (S) protein. Here, we characterize a panel of mAbs targeting the N-terminal domain (NTD) or other non-RBD epitopes of S. A subset of NTD mAbs inhibits SARS-CoV-2 entry at a post-attachment step and avidly binds the surface of infected cells. One neutralizing NTD mAb, SARS2-57, protects K18-hACE2 mice against SARS-CoV-2 infection in an Fc-dependent manner. Structural analysis demonstrates that SARS2-57 engages an antigenic supersite that is remodeled by deletions common to emerging variants. In neutralization escape studies with SARS2-57, this NTD site accumulates mutations, including a similar deletion, but the addition of an anti-RBD mAb prevents such escape. Thus, our study highlights a common strategy of immune evasion by SARS-CoV-2 variants and how targeting spatially distinct epitopes, including those in the NTD, may limit such escape

Cholesterol 25-hydroxylase suppresses SARS-CoV-2 replication by blocking membrane fusion

Cholesterol 25-hydroxylase (CH25H) is an interferon (IFN)-stimulated gene that shows broad antiviral activities against a wide range of enveloped viruses. Here, using an IFN-stimulated gene screen against vesicular stomatitis virus (VSV)-SARS-CoV and VSV-SARS-CoV-2 chimeric viruses, we identified CH25H and its enzymatic product 25-hydroxycholesterol (25HC) as potent inhibitors of SARS-CoV-2 replication. Internalized 25HC accumulates in the late endosomes and potentially restricts SARS-CoV-2 spike protein catalyzed membrane fusion via blockade of cholesterol export. Our results highlight one of the possible antiviral mechanisms of 25HC and provide the molecular basis for its therapeutic development

Measurement of the ratios of branching fractions R(D∗)\mathcal{R}(D^{*}) and R(D0)\mathcal{R}(D^{0})

The ratios of branching fractions $\mathcal{R}(D^{*})\equiv\mathcal{B}(\bar{B}\to D^{*}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(\bar{B}\to D^{*}\mu^{-}\bar{\nu}_{\mu})$ and $\mathcal{R}(D^{0})\equiv\mathcal{B}(B^{-}\to D^{0}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(B^{-}\to D^{0}\mu^{-}\bar{\nu}_{\mu})$ are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0 fb${ }^{-1}$ of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode $\tau^{-}\to\mu^{-}\nu_{\tau}\bar{\nu}_{\mu}$. The measured values are $\mathcal{R}(D^{*})=0.281\pm0.018\pm0.024$ and $\mathcal{R}(D^{0})=0.441\pm0.060\pm0.066$, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is $\rho=-0.43$. Results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the Standard Model.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-039.html (LHCb public pages

Topological perturbations on resilience of the world trade competition network

Abstract Network resilience refers to a system’s capability to adapt its functions to ensure continuity of essential operations amidst external environmental shifts or internal failures. The resilience of the world trade network faces structural disturbances, such as dynamic changes in the internal and external environments, increasing trade barriers and changes in competition between countries, which is an issue worth exploring. In this study, we introduce a world trade competition network that reflects export competition between two countries. We employ a network dynamics model to assess the resilience of this global trade competition network, focusing on the influence of topological disturbances. The eight distinct types of topological perturbations analyzed include nodes representing countries, links symbolizing inter-country competition, and weights indicative of the intensity of this competition. Our findings reveal that the intensity of export competition between countries significantly influences the resilience of the global trade competition network. Specifically, experimental outcomes indicate that network resilience declines more rapidly when nodes are removed sequentially based on higher weighted degrees than when based on lower ones. Similarly, in link perturbation scenarios, removing links associated with higher competition intensity first leads to a more precipitous decrease in network resilience when the network is otherwise stable. Furthermore, in weight alteration scenarios, networks maintaining a higher ratio of high-intensity competition links demonstrate greater stability compared to those with a reduced proportion of such links. Consequently, sustaining a robust level of export competition between countries is crucial for preserving the stability of the network

CoV2-TCR: A web server for screening TCR CDR3 from TCR immune repertoire of COVID-19 patients and their recognized SARS-CoV-2 epitopes

Although multiple vaccines have been developed and widely administered, several severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have been reported to evade immune responses and spread diffusely. Here, 108 RNA-seq files from coronavirus disease 2019 (COVID-19) patients and healthy donors (HD) were downloaded to extract their TCR immune repertoire by MiXCR. Those extracted TCR repertoire were compared and it was found that disease progression was related negatively with diversity and positively with clonality. Specifically, greater proportions of high-abundance clonotypes were observed in active and severe COVID-19 samples, probably resulting from strong stimulation of SARS-CoV-2 epitopes and a continued immune response in host. To investigate the specific recognition between TCR CDR3 and SARS-CoV-2 epitopes, we constructed an accurate classifier CoV2-TCR with an AUC of 0.967 in an independent dataset, which outperformed several similar tools. Based on this model, we observed a huge range in the number of those TCR CDR3 recognizing those different peptides, including 28 MHC-I epitopes from SARS-CoV-2 and 22 immunogenic peptides from SARS-CoV-2 variants. Interestingly, their proportions of high-abundance, low-abundance and rare clonotypes were close for each peptide. To expand the potential application of this model, we established the webserver, CoV2-TCR, in which users can obtain those recognizing CDR3 sequences from the TCR repertoire of COVID-19 patients based on the 9-mer peptides containing mutation site(s) on the four main proteins of SARS-CoV-2 variants. Overall, this study provides preliminary screening for candidate antigen epitopes and the TCR CDR3 that recognizes them, and should be helpful for vaccine design on SARS-CoV-2 variants