A significant body of research has documented the profound changes in global atmospheric conditions during the COVID-19 pandemic. However, there is still an inadequate comprehensive comparison and assessment of countries before, during, and after the pandemic. Variations in restriction policies, human behaviors, and national traits lead to significant differences in how restriction policies affect atmospheric pollution.
View Article and Find Full Text PDFInt J Antimicrob Agents
August 2024
Phage therapy offers a promising approach to combat the growing threat of antimicrobial resistance. Yet, key questions remain regarding dosage, administration routes, combination therapy, and the causes of therapeutic failure. In this study, we focused on a novel lytic phage, ФAb4B, which specifically targeted the Acinetobacter baumannii strains with KL160 capsular polysaccharide, including the pan-drug resistant A.
View Article and Find Full Text PDFT-cell acute lymphoblastic leukemia (T-ALL) is an aggressive subtype of ALL characterized by its high heterogeneity and unfavorable clinical features. Despite improved insights in genetic and epigenetic landscapes of T-ALL, the molecular mechanisms that drive malignant T-cell development remain unclear. BTB and CNC homology 2 (BACH2) is a lymphoid-specific transcription repressor recognized as a tumor suppressor in B-cell malignancies, but little is known about its function and regulatory network in T-ALL.
View Article and Find Full Text PDFSeminoma is the most common malignant solid tumor in 14 to 44 year-old men. However, its molecular features and tumor microenvironment (TME) is largely unexplored. Here, we perform a series of studies via genomics profiling (single cell multi-omics and spatial transcriptomics) and functional examination using seminoma samples and a seminoma cell line.
View Article and Find Full Text PDFSince bacteriophages (phages) were firstly reported at the beginning of the 20th century, the study on them experiences booming-fading-emerging with discovery and overuse of antibiotics. Although they are the hotspots for therapy of antibiotic-resistant strains nowadays, natural phage applications encounter some challenges such as limited host range and bacterial resistance to phages. Synthetic biology, one of the most dramatic directions in the recent 20-years study of microbiology, has generated numerous methods and tools and has contributed a lot to understanding phage evolution, engineering modification, and controlling phage-bacteria interactions.
View Article and Find Full Text PDFActivating transcription factor 3 (ATF3) is a stress-inducible gene reported with anti-inflammatory response effects against bacterial infections. This study focuses on the function of ATF3 in alveolar epithelial type II cells (A549) following Mycobacterium tuberculosis (MTB) infection. First, RT-qPCR results detected reduced ATF3 expression in broncho-alveolar lavage fluid (BALF) of MTB-infected patients, whereas the ATF3 level was upregulated in A549 cells at early stages after MTB infection but decreased later.
View Article and Find Full Text PDFOverexpressed Mdm2 and its 7homolog MdmX impair p53 activity in many cancers. Small molecules mimicking a p53 peptide can effectively inhibit Mdm2 but not MdmX. Here, we show a strategy for improving lead compounds for Mdm2 and MdmX inhibition based on the multivalency of the p53 peptide.
View Article and Find Full Text PDFAntimicrobial resistance (AMR) is a global crisis for human public health which threatens the effective prevention and control of ever-increasing infectious diseases. The advent of pandrug-resistant bacteria makes most, if not all, available antibiotics invalid. Meanwhile, the pipeline of novel antibiotics development stagnates, which prompts scientists and pharmacists to develop unconventional antimicrobials.
View Article and Find Full Text PDFThe present study aimed to investigate the regulatory mechanism of chemokine (C-X-C motif) receptor 4 (CXCR4) on endothelial progenitor cells (EPCs) through the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway under hypoxic conditions. Mononuclear cells were isolated from the bone marrow (BM) of young Sprague-Dawley (SD) rats. Bone marrow-derived endothelial progenitor cells (BM-EPCs) were characterized by using Dil-labeled acetylated low-density lipoprotein (Dil-ac-LDL) and fluorescein isothiocyanate-labeled UEA (FITC-UEA-1).
View Article and Find Full Text PDFBackground: The importance of microRNAs (miRs) has been documented in infections. This study estimated the role of miR-340-5p in (Mtb)-infected alveolar type II cells.
Methods: The microarray of GEO database was analyzed to find the differentially expressed miRs caused by Mtb infection, and miR-340-5p was selected as the research object.
Tau is a microtubule-associated protein involved in regulation of assembly and spatial organization of microtubule in neurons. However, in pathological conditions, tau monomers assemble into amyloid filaments characterized by the cross-β structures in a number of neurodegenerative diseases known as tauopathies. In this review, we summarize recent progression on the characterization of structures of tau monomer and filament, as well as the dynamic liquid droplet assembly.
View Article and Find Full Text PDFSignal Transduct Target Ther
August 2020
The global Coronavirus disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 has affected more than eight million people. There is an urgent need to investigate how the adaptive immunity is established in COVID-19 patients. In this study, we profiled adaptive immune cells of PBMCs from recovered COVID-19 patients with varying disease severity using single-cell RNA and TCR/BCR V(D)J sequencing.
View Article and Find Full Text PDFIn preclinical and phase I and II clinical studies, 2'-deoxy-2'-β-fluoro-4'-azidocytidine (FNC) displays a potent and long-lasting inhibition of HIV-1 infection. To investigate its mechanism of action, we compared it with the well-documented lamivudine (3TC). Pharmacokinetic studies revealed that the intracellular retention of FNC triphosphate in peripheral blood mononuclear cells was markedly longer than that of the 3TC triphosphate.
View Article and Find Full Text PDFThe αβ T cell receptor (TCR), in association with the CD3γε-CD3δε-CD3ζζ signalling hexamer, is the primary determinant of T cell development and activation, and of immune responses to foreign antigens. The mechanism of assembly of the TCR-CD3 complex remains unknown. Here we report a cryo-electron microscopy structure of human TCRαβ in complex with the CD3 hexamer at 3.
View Article and Find Full Text PDFCyclization of the polypeptide backbone has proven to be a powerful strategy for enhancing protein stability for fundamental research and pharmaceutical application. The use of such an approach is restricted by how well a targeted polypeptide can be efficiently ligated. Recently, an Asx-specific peptide ligase identified from a tropical cyclotide-producing plant and named butelase 1 exhibited excellent cyclization kinetics that cannot be matched by other known ligases, including intein, PATG, PCY1, and sortase A.
View Article and Find Full Text PDFThe RNA-guided endonucleases of the CRISPR-Cas9 system, including the most widely used Cas9 from Streptococcus pyogenes (SpCas9), are becoming a robust genome editing tool in model organisms and hold immense promise for therapeutic applications. Many strategies have been employed to overcome the limitations caused by SpCas9's off-target effects and its stringent requirement for the protospacer adjacent motif (PAM) sequence. However, the structural mechanisms underlying these strategies remain undefined.
View Article and Find Full Text PDFThe CRISPR-Cas systems, as exemplified by CRISPR-Cas9, are RNA-guided adaptive immune systems used by bacteria and archaea to defend against viral infection. The CRISPR-Cpf1 system, a new class 2 CRISPR-Cas system, mediates robust DNA interference in human cells. Although functionally conserved, Cpf1 and Cas9 differ in many aspects including their guide RNAs and substrate specificity.
View Article and Find Full Text PDFThe human immunodeficiency virus (HIV)-1 protein Vif has a central role in the neutralization of host innate defences by hijacking cellular proteasomal degradation pathways to subvert the antiviral activity of host restriction factors; however, the underlying mechanism by which Vif achieves this remains unclear. Here we report a crystal structure of the Vif-CBF-β-CUL5-ELOB-ELOC complex. The structure reveals that Vif, by means of two domains, organizes formation of the pentameric complex by interacting with CBF-β, CUL5 and ELOC.
View Article and Find Full Text PDFInt J Bioinform Res Appl
March 2014
Subcellular localisation is a key functional characteristic of proteins. In this paper, we apply Haralick texture analysis and Curvelet Transform for feature description and propose a cascade Random Subspace (RS) ensemble with rejection options for subcellular phenotype classification. Serial fusions of RS classifier ensembles much improve classification reliability.
View Article and Find Full Text PDFPorcine epidemic diarrhea virus (PEDV) is the cause of an economically important swine disease. Previous studies suggested that PEDV does not elicit a robust IFN response, but the mechanism(s) used to evade or block this innate immune response was not known. In this study, we found that PEDV infection blocked synthetic dsRNA-induced IFN-β production by interfering with the activation of interferon regulatory factor 3 (IRF3).
View Article and Find Full Text PDFDiagn Microbiol Infect Dis
April 2013
BMC Bioinformatics
April 2011
Background: Automated, image based high-content screening is a fundamental tool for discovery in biological science. Modern robotic fluorescence microscopes are able to capture thousands of images from massively parallel experiments such as RNA interference (RNAi) or small-molecule screens. As such, efficient computational methods are required for automatic cellular phenotype identification capable of dealing with large image data sets.
View Article and Find Full Text PDFJ Neurosci Methods
October 2007
The molecular and cellular bases of neuronal cell death that underpin a wide range of neurodegenerative disorders are still not well understood. One approach to investigating neuronal death is through systematic studies of the changing morphology of cultured brain neurons in response to cellular challenges. Image segmentation methods developed to date to analyze such changes have been limited by the low contrast of cells in unstained neuronal cultures and the unimodal histograms generated by these analyses.
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