ABSTRACT
Bacterial double-stranded DNA (dsDNA) cytosine deaminase DddAtox-derived cytosine base editor (DdCBE) and its evolved variant, DddA11, guided by transcription-activator-like effector (TALE) proteins, enable mitochondrial DNA (mtDNA) editing at TC or HC (H = A, C, or T) sequence contexts, while it remains relatively unattainable for GC targets. Here, we identified a dsDNA deaminase originated from a Roseburia intestinalis interbacterial toxin (riDddAtox) and generated CRISPR-mediated nuclear DdCBEs (crDdCBEs) and mitochondrial CBEs (mitoCBEs) using split riDddAtox, which catalyzed C-to-T editing at both HC and GC targets in nuclear and mitochondrial genes. Moreover, transactivator (VP64, P65, or Rta) fusion to the tail of DddAtox- or riDddAtox-mediated crDdCBEs and mitoCBEs substantially improved nuclear and mtDNA editing efficiencies by up to 3.5- and 1.7-fold, respectively. We also used riDddAtox-based and Rta-assisted mitoCBE to efficiently stimulate disease-associated mtDNA mutations in cultured cells and in mouse embryos with conversion frequencies of up to 58% at non-TC targets.
Subject(s)
Gene Editing , Trans-Activators , Mice , Animals , Trans-Activators/metabolism , Cytosine , Mutation , DNA, Mitochondrial/genetics , CRISPR-Cas SystemsABSTRACT
With its estrogenic activity, (S)-equol plays an important role in maintaining host health and preventing estrogen-related diseases. Exclusive production occurs through the transformation of soy isoflavones by intestinal bacteria, but the reasons for variations in (S)-equol production among different individuals and species remain unclear. Here, fecal samples from humans, pigs, chickens, mice, and rats were used as research objects. The concentrations of (S)-equol, along with the genetic homology and evolutionary relationships of (S)-equol production-related genes [daidzein reductase (DZNR), daidzein racemase (DDRC), dihydrodaidzein reductase (DHDR), tetrahydrodaidzein reductase (THDR)], were analyzed. Additionally, in vitro functional verification of the newly identified DDRC gene was conducted. It was found that approximately 40% of human samples contained (S)-equol, whereas 100% of samples from other species contained (S)-equol. However, there were significant variations in (S)-equol content among the different species: rats > pigs > chickens > mice > humans. The distributions of the four genes displayed species-specific patterns. High detection rates across various species were exhibited by DHDR, THDR, and DDRC. In contrast, substantial variations in detection rates among different species and individuals were observed with respect to DZNR. It appears that various types of DZNR may be associated with different concentrations of (S)-equol, which potentially correspond to the regulatory role during (S)-equol synthesis. This enhances our understanding of individual variations in (S)-equol production and their connection with functional genes in vitro. Moreover, the newly identified DDRC exhibits higher potential for (S)-equol synthesis compared to the known DDRC, providing valuable resources for advancing in vitro (S)-equol production. IMPORTANCE: (S)-equol ((S)-EQ) plays a crucial role in maintaining human health, along with its known capacity to prevent and treat various diseases, including cardiovascular diseases, metabolic syndromes, osteoporosis, diabetes, brain-related diseases, high blood pressure, hyperlipidemia, obesity, and inflammation. However, factors affecting individual variations in (S)-EQ production and the underlying regulatory mechanisms remain elusive. This study examines the association between functional genes and (S)-EQ production, highlighting a potential correlation between the DZNR gene and (S)-EQ content. Various types of DZNR may be linked to the regulation of (S)-EQ synthesis. Furthermore, the identification of a new DDRC gene offers promising prospects for enhancing in vitro (S)-EQ production.
Subject(s)
Equol , Isoflavones , Animals , Humans , Mice , Rats , Swine , Equol/genetics , Equol/metabolism , Racemases and Epimerases , Chickens/metabolism , Isoflavones/metabolism , Oxidoreductases/metabolismABSTRACT
The genetic identification of skeletal remains from Chinese People's Volunteers (CPVs) of the Korean War has been challenging because of the degraded DNA samples and the lack of living close relatives. This study established a workflow for identifying CPVs by combining Y-chromosome short tandem repeats (Y-STRs), mitochondrial DNA (mtDNA) hypervariable regions I and II, autosomal STRs (aSTRs), and identity-informative SNPs (iiSNPs). A total of 20 skeletal remains of CPVs and 46 samples from their alleged relatives were collected. The success rate of DNA extraction from human remains was 100%. Based on Y-STRs, six remains shared the same male lineages with their alleged relatives. Meanwhile, mtDNA genotyping supports two remains sharing the same maternal lineages with their alleged relatives. Likelihood ratios (LRs) were further obtained from 27 aSTRs and 94 iiSNPs or 1936 iiSNPs to confirm their relationship. All joint pedigree LRs were >100. Finally, six remains were successfully identified. This pilot study for the systematic genetic identification of CPVs from the Korean War can be applied for the large-scale identification of CPVs in the future.
Subject(s)
Asian People , Chromosomes, Human, Y , DNA, Mitochondrial , Korean War , Microsatellite Repeats , Polymorphism, Single Nucleotide , Humans , DNA, Mitochondrial/genetics , DNA, Mitochondrial/analysis , Male , Microsatellite Repeats/genetics , Chromosomes, Human, Y/genetics , Asian People/genetics , Body Remains , Forensic Genetics/methods , Female , Pedigree , Pilot ProjectsABSTRACT
The ABO blood group plays an important role in blood transfusion, linkage analysis, individual identification, etc. Serologic methods of blood typing are gold standards for the time being, which require stable typing antisera and fresh blood samples and are labor intensive. At present, reliable determination of ABO blood group genotypes based on single-nucleotide polymorphisms (SNPs) among A, B, and O alleles remains necessary. Thus, in this work, CRISPR/Cas13a-mediated genotyping for the ABO blood group by detecting SNPs between different alleles was proposed. The ABO*O.01.01(c.261delG) allele (G for the A/B allele and del for the O allele) and ABO*B.01(c.796C > A) allele (C for the A/O allele and A for the B allele) were selected to determine the six genotypes (AA, AO, BB, BO, OO, and AB) of the ABO blood group. Multiplex PCR was adapted to simultaneously amplify the two loci. CRISPR/Cas13a was then used to specifically differentiate ABO*O.01.01(c.261delG) and ABO*B.01(c.796C > A) of A, B, and O alleles. Highly accurate determination of different genotypes was achieved with a limit of detection of 50 pg per reaction within 60 min. The reliability of this method was further validated based on its applicability in detecting buccal swab samples with six genotypes. The results were compared with those of serological and sequencing methods, with 100% accuracy. Thus, the CRISPR/Cas13a-mediated assay shows great application potential in the reliable identification of ABO blood group genotypes in a wide range of samples, eliminating the need to collect fresh blood samples in the traditional method.
Subject(s)
ABO Blood-Group System , Polymorphism, Single Nucleotide , ABO Blood-Group System/genetics , Reproducibility of Results , Clustered Regularly Interspaced Short Palindromic Repeats , Genotype , Multiplex Polymerase Chain ReactionABSTRACT
Chronic Hepatitis B virus (CHB) infection is a global health challenge, causing damage ranging from hepatitis to cirrhosis and hepatocellular carcinoma. In our study, single-cell RNA sequencing (scRNA-seq) analysis was performed in livers from mice models with chronic inflammation induced by CHB infection and we found that endothelial cells (ECs) exhibited the largest number of differentially expressed genes (DEGs) among all ten cell types. NF-κB signaling was activated in ECs to induce cell dysfunction and subsequent hepatic inflammation, which might be mediated by the interaction of macrophage-derived and cholangiocyte-derived VISFATIN/Nampt signaling. Moreover, we divided ECs into three subclusters, including periportal ECs (EC_Z1), midzonal ECs (EC_Z2), and pericentral ECs (EC_Z3) according to hepatic zonation. Functional analysis suggested that pericentral ECs and midzonal ECs, instead of periportal ECs, were more vulnerable to HBV infection, as the VISFATIN/Nampt- NF-κB axis was mainly altered in these two subpopulations. Interestingly, pericentral ECs showed increasing communication with macrophages and cholangiocytes via the Nampt-Insr and Nampt-Itga5/Itgb1 axis upon CHB infection, which contribute to angiogenesis and vascular capillarization. Additionally, ECs, especially pericentral ECs, showed a close connection with nature killer (NK) cells and T cells via the Cxcl6-Cxcr6 axis, which is involved in shaping the microenvironment in CHB mice livers. Thus, our study described the heterogeneity and functional alterations of three subclusters in ECs. We revealed the potential role of VISFATIN/Nampt signaling in modulating ECs characteristics and related hepatic inflammation, and EC-derived chemokine Cxcl16 in shaping NK and T cell recruitment, providing key insights into the multifunctionality of ECs in CHB-associated pathologies.
Subject(s)
Endothelial Cells , Hepatitis B, Chronic , Single-Cell Analysis , Animals , Hepatitis B, Chronic/virology , Hepatitis B, Chronic/genetics , Hepatitis B, Chronic/metabolism , Mice , Endothelial Cells/metabolism , Endothelial Cells/virology , Sequence Analysis, RNA , Hepatitis B virus/genetics , Hepatitis B virus/physiology , Signal Transduction , Liver/metabolism , Liver/virology , Liver/pathology , NF-kappa B/metabolism , Male , Nicotinamide Phosphoribosyltransferase/metabolism , Nicotinamide Phosphoribosyltransferase/genetics , Disease Models, Animal , Mice, Inbred C57BL , HumansABSTRACT
Human bocavirus 1 (HBoV1), an autonomous human parvovirus, causes acute respiratory tract infections in young children. HBoV1 infects well-differentiated (polarized) human airway epithelium cultured at an air-liquid interface (HAE-ALI). HBoV1 expresses a large nonstructural protein, NS1, that is essential for viral DNA replication. HBoV1 infection of polarized human airway epithelial cells induces a DNA damage response (DDR) that is critical to viral DNA replication involving DNA repair with error-free Y-family DNA polymerases. HBoV1 NS1 or the isoform NS1-70 per se induces a DDR. In this study, using the second-generation proximity-dependent biotin identification (BioID2) approach, we identified that Ku70 is associated with the NS1-BioID2 pulldown complex through a direct interaction with NS1. Biolayer interferometry (BLI) assay determined a high binding affinity of NS1 with Ku70, which has an equilibrium dissociation constant (KD) value of 0.16 µM and processes the strongest interaction at the C-terminal domain. The association of Ku70 with NS1 was also revealed during HBoV1 infection of HAE-ALI. Knockdown of Ku70 and overexpression of the C-terminal domain of Ku70 significantly decreased HBoV1 replication in HAE-ALI. Thus, our study provides, for the first time, a direct interaction of parvovirus large nonstructural protein NS1 with Ku70. IMPORTANCE Parvovirus infection induces a DNA damage response (DDR) that plays a pivotal role in viral DNA replication. The DDR includes activation of ATM (ataxia telangiectasia mutated), ATR (ATM- and RAD3-related), and DNA-PKcs (DNA-dependent protein kinase catalytic subunit). The large nonstructural protein (NS1) often plays a role in the induction of DDR; however, how the DDR is induced during parvovirus infection or simply by the NS1 is not well studied. Activation of DNA-PKcs has been shown as one of the key DDR pathways in DNA replication of HBoV1. We identified that HBoV1 NS1 directly interacts with Ku70, but not Ku80, of the Ku70/Ku80 heterodimer at high affinity. This interaction is also important for HBoV1 replication in HAE-ALI. We propose that the interaction of NS1 with Ku70 recruits the Ku70/Ku80 complex to the viral DNA replication center, which activates DNA-PKcs and facilitates viral DNA replication.
Subject(s)
Human bocavirus/physiology , Ku Autoantigen/metabolism , Respiratory Mucosa/virology , Viral Nonstructural Proteins/metabolism , Virus Replication , DNA Damage , DNA Replication , DNA, Viral/biosynthesis , Genome, Viral , HEK293 Cells , Human bocavirus/metabolism , Humans , Ku Autoantigen/genetics , Protein Binding , Protein Domains , Respiratory Mucosa/metabolism , Viral Nonstructural Proteins/genetics , Viral Replication Compartments/metabolismABSTRACT
Baicalin (7-d-glucuronic acid-5, 6-dihydroxyflavone) derived from the root of Scutellaria baicalensis used as Traditional Chinese Medicine (TCM) has been revealed to exert potential antiviral activity via various pathways, while the molecular mechanisms have not been fully understood. Pyroptosis, an inflammatory form of programmed cell death (PCD), is reported to play a crucial role in host cell fate during viral infection. In this study, transcriptome analysis of mice lung tissue reveals that baicalin reverses the alterations of the mRNA levels of PCD-associated genes upon H1N1 challenge, with a concomitant decrease in the population of H1N1-induced propidium iodide (PI)+ and Annexin â ¤+ cells. Intriguingly, we find that baicalin contributes to the survival of infected lung alveolar epithelial cells partly through its inhibition of H1N1-induced cell pyroptosis, which is manifested by reduced bubble-like protrusion cells and lactate dehydrogenase (LDH) release. Moreover, the antipyroptosis effect of baicalin in response to H1N1 infection is found to be mediated by its repression on caspase-3/Gasdermin E (GSDME) pathway. Cleaved caspase-3 and N-terminal fragment of GSDME (GSDME-N) are detected in H1N1-infected cell lines and mice lung tissues, which are markedly reversed by baicalin treatment. Furthermore, inhibition of caspase-3/GSDME pathway by caspase-3 inhibitor or siRNA exerts an antipyroptosis effect equal to that of baicalin treatment in infected A549 and BEAS-2B cells, indicating a pivotal role of caspase-3 in the antiviral activities of baicalin. Conclusively, for the first time, we demonstrate that baicalin could effectively suppress H1N1-induced pyroptosis of lung alveolar epithelial cells via caspase-3/GSDME pathway both in vitro and in vivo.
Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza, Human , Animals , Mice , Humans , Pyroptosis , Alveolar Epithelial Cells/metabolism , Influenza, Human/drug therapy , Caspase 3/genetics , Caspase 3/metabolism , Lung/metabolism , Antiviral Agents/pharmacologyABSTRACT
Achromatic metalenses formed using previous design methods face a compromise between diameter, numerical aperture, and working wave band. To address this problem, the authors coat the refractive lens with a dispersive metasurface and numerically demonstrate a centimeter-scale hybrid metalens for the visible band of 440-700â nm. By revisiting the generalized Snell law, a universal design of a chromatic aberration correction metasurface is proposed for a plano-convex lens with arbitrary surface curvatures. A highly precise semi-vector method is also presented for large-scale metasurface simulation. Benefiting from this, the reported hybrid metalens is carefully evaluated and exhibits 81% chromatic aberration suppression, polarization insensitivity, and broadband imaging capacity.
ABSTRACT
BACKGROUND: Insertion and deletion (InDel) polymorphisms have considerable potential in the field of forensic genetics because of their low mutation rate and small amplicons. At present, InDel polymorphisms detection based on the technique of capillary electrophoresis is the main technique used in forensic DNA laboratory. However, this method is complicated and time-consuming, and is not suitable for rapid on-site paternity and personal identification. Next-generation sequencing analysis of InDels polymorphisms requires expensive instruments, large upfront reagent and supply costs, computational requirements and complex bioinformatics, increased the time to obtain results. Thus, there is an urgent need to establish a method to provide reliable, rapid, sensitive and economical genotyping for InDels. METHOD: A rapid InDels (32 InDels) panel was established using fluorogenic probes-based multiplex real-time PCR with microfluidic test cartridge and portable real-time PCR instrument. Then, we performed several validation studies including concordance, accuracy, sensitivity, stability, species specificity. RESULTS: It showed that the complete genotypes could be obtained from ≥100 pg of input DNA and from a series of challenging samples with high accuracy and specificity within 90 min. CONCLUSION: This method provides a rapid and cost-effective solution for InDels genotyping and personal identification in portable format.
Subject(s)
Forensic Anthropology , Polymorphism, Genetic , Humans , Genotype , Real-Time Polymerase Chain Reaction , DNA/analysisABSTRACT
Tumor necrosis factor alpha (TNF-α) is a critical pro-inflammatory cytokine in a wide range of tumors and infectious diseases. This study showed for the first time that TNF-α could specifically bind to certain intracellular or circulating inflammation-related microRNAs both in vitro and in vivo. The binding sites of TNF-α to microRNAs are located at the N-terminal of TNF-α and the 3'-GGUU motif of microRNAs. TNF-α could deliver exogenous unmodified single-stranded microRNAs into recipient cells through the TNF-α receptors (TNFRs) and stabilize them from being degraded by RNase in cells. Exogenous miR-146a or let-7c delivered into HCT116 cells by TNF-α could escape from lysosomes and specifically downregulate their target genes and then affect cell proliferation and migration in vitro, as well as tumorigenesis in vivo. Based on the above findings, the concept of "non-conjugated ligand-mediated RNA delivery (ncLMRD)" was proposed, which may serve as a promising strategy for therapeutic microRNA delivery in the future.
Subject(s)
MicroRNAs , Tumor Necrosis Factor-alpha , Cells, Cultured , Cytokines , Humans , Inflammation , MicroRNAs/genetics , MicroRNAs/metabolism , Tumor Necrosis Factor-alpha/metabolismABSTRACT
The outbreak of the monkeypox virus (MPXV) worldwide in 2022 highlights the need for a rapid and low-cost MPXV detection tool for effectively monitoring and controlling monkeypox disease. In this study, we developed a flexible lateral flow immunoassay (LFIA) with strong colorimetric and enhanced fluorescence dual-signal output for the rapid, on-site, and highly sensitive detection of the MPXV antigen in different scenarios. A multilayered SiO2-Au core dual-quantum dot (QD) shell nanocomposite (named SiO2-Au/DQD), which consists of a large SiO2 core (~ 200 nm), one layer of density-controlled gold nanoparticles (AuNPs, 20 nm), and thousands of small QDs, was fabricated instead of a traditional colorimetric nanotag (i.e., AuNPs) and a fluorescent nanotag (QD nanobead) to simultaneously provide good stability, strong colorimetric ability and superior fluorescence intensity. With the dual-signal output LFIA, we achieved the specific screening of the MPXV antigen (A29L) in 15 min, with detection limits of 0.5 and 0.0021 ng/mL for the colorimetric and fluorometric modes, respectively. Moreover, the colorimetric mode of SiO2-Au/DQD-LFIA exhibits the same sensitivity as the traditional AuNP- LFIA, whereas the overall sensitivity of this method on the basis of the fluorescent signal can achieve 238- and 3.3-fold improvements in sensitivity for MPXV compared with the AuNP-based LFIA and ELISA methods, respectively, indicating the powerful performance and good versatility of the dual-signal method in the point-of-care testing of the MPXV.
Subject(s)
Metal Nanoparticles , Monkeypox virus , Gold , Silicon Dioxide , Immunoassay/methods , Limit of DetectionABSTRACT
Liver injury caused by hepatitis is the pathological basis of varied hepatic diseases with high morbidity and mortality. Although siRNA appears promising in therapeutics of hepatitis, efficient and safe delivery remains a challenge. In this study, we developed a new strategy of incorporating glycyrrhizic acid (GA) and polyene phosphatidylcholine (PPC) into lipid nanoparticles (GA/PPC-modified LNPs), which was capable of promoting cellular uptake, enhancing gene-silencing, reducing cytotoxicity and improving siRNA stability. GA/PPC-modified LNP and siRNA lipoplex targeting NF-κB, a key mediator of inflammation, mitigates acute liver injury, as assessed by liver histology, hematological and pro-inflammatory cytokine analysis. Furthermore, GA/PPC-modified LNPs reveal efficiently intracellular delivery of antisense oligonucleotides (ASOs) and mRNA inhibiting viral infection. In conclusion, GA/PPC-modified LNPs could be used as a promising delivery system for nucleic acid-based therapy.
Subject(s)
Glycyrrhizic Acid , Nanoparticles , RNA, Small Interfering , Glycyrrhizic Acid/pharmacology , Glycyrrhizic Acid/metabolism , LiverABSTRACT
Heat stress leads to milk production losses and mammary gland inflammation, which may be associated with mammary epithelium damage. Taurine is one of the most abundant free amino acids in mammals which has anti-inflammatory properties. This study aimed to explore the effect of taurine pretreatment on heat stress-induced mammary epithelial integrity disruption and inflammatory damage. In our first experiment on dairy cows our results showed that compared with animals under autumn thermoneutral condition (THI = 62.99 ± 0.71), summer heat stress (THI = 78.01 ± 0.39) significantly reduced milk yield and disrupted mammary epithelial integrity as revealed by increased concentrations of serotonin and lactose in plasma, and increased levels of SA and Na+/K+ in milk. In our second study, 36 lactating mice were randomly divided into three groups (n = 12) for a 9d experiment using a climate chamber to establish a heat stress model. Our findings suggest taurine pretreatment could attenuate heat stress-induced mammary histopathological impairment, inflammation response, and enhance mammary epithelium integrity, which was mainly achieved by promoting the secretion of ZO-1, Occludin, and Claudin-3 through inhibiting activation of the ERK1/2-MLCK signaling pathway in the mammary gland. Overall, our findings indicated that heat stress induced mammary epithelium dysfunction in dairy cows, and emphasized the protective effect of taurine on mammary health under heat stress conditions using a mouse model, which may be achieved by alleviating the mammary epithelium integrity damage and inflammation response.
Subject(s)
Lactation , MAP Kinase Signaling System , Animals , Cattle , Female , Heat-Shock Response , Inflammation/drug therapy , Inflammation/metabolism , Mammals , Mammary Glands, Animal/physiology , Milk/chemistry , Signal Transduction , MiceABSTRACT
The exceptionally widespread outbreak of human monkeypox, an emerging zoonosis caused by the monkeypox virus (MPXV), with more than 69,000 confirmed cases in 100 non-endemic countries since 2022, is a major public health concern. Codon usage patterns reflect genetic variation and adaptation to new hosts and ecological niches. However, detailed analyses of codon usage bias in MPXV based on large-scale genomic data, especially for strains responsible for the 2022 outbreak, are lacking. In this study, we analyzed codon usage in MPXV and its relationship with host adaptation. We confirmed the ongoing outbreak of MPXVs belonging to the West Africa (WA) lineage by principal component analysis based on their codon usage patterns. The 2022 outbreak strains had a relatively low codon usage bias. Codon usage of MPXVs was shaped by mutation and natural selection; however, different from past strains, codon usage in the 2022 outbreak strains was predominantly determined by mutation pressure. Additionally, as revealed by the codon adaptation index (CAI), relative codon deoptimization index (RCDI), and similarity index (SiD) analyses, the codon usage patterns of MPXVs were also affected by their hosts. In particular, the 2022 outbreak strains showed slightly but significantly greater adaptation to many primates, including humans, and were subjected to stronger selection pressure induced by hosts. Our results suggest that MPXVs contributing to the 2022 outbreak have unique evolutionary features, emphasizing the importance of sustained monitoring of their transmission and evolution.
Subject(s)
Codon Usage , Host Adaptation , Animals , Humans , Monkeypox virus/genetics , Phylogeny , Evolution, Molecular , Codon/genetics , Selection, Genetic , Disease OutbreaksABSTRACT
Skeleton and teeth are important biological samples. Due to their special structure and strong ability to resist degradation, they are ideal biological materials to retain DNA under natural condition. In many cases, such as historical figure identification, aged skeleton and teeth are usually the only biological samples. However, their DNA is in a state of trace, damage and degradation to different degrees, which requires special experimental treatment to achieve identification. This paper reviews the sample selection, DNA extraction, DNA enrichment and analysis approaches based on relevant research reports in recent years, aiming to promote the further development and improvement of the aged skeleton and teeth identification system.
Subject(s)
Body Remains , Tooth , Humans , Aged , DNA/genetics , DNA/analysis , DNA Fingerprinting , Sequence Analysis, DNAABSTRACT
To rapidly identify individuals infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and control the spread of coronavirus disease (COVID-19), there is an urgent need for highly sensitive on-site virus detection methods. A clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas)-based molecular diagnostic method was developed for this purpose. Here, a CRISPR system-mediated lateral flow assay (LFA) for SARS-CoV-2 was established based on multienzyme isothermal rapid amplification, CRISPR-Cas13a nuclease, and LFA. To improve the limit of detection (LoD), the crispr RNA, amplification primer, and probe were screened, in addition to concentrations of various components in the reaction system. The LoD of CRISPR detection was improved to 0.25 copy/µl in both fluorescence- and immunochromatography-based assays. To enhance the quality control of the CRISPR-based LFA method, glyceraldehyde-3-phosphate dehydrogenase was detected as a reference using a triple-line strip design in a lateral flow strip. In total, 52 COVID-19-positive and 101 COVID-19-negative clinical samples examined by reverse transcription polymerase chain reaction (RT-PCR) were tested using the CRISPR immunochromatographic detection technique. Results revealed 100% consistency, indicating the comparable effectiveness of our method to that of RT-PCR. In conclusion, this approach significantly improves the sensitivity and reliability of CRISPR-mediated LFA and provides a crucial tool for on-site detection of SARS-CoV-2.
Subject(s)
COVID-19 , CRISPR-Associated Proteins , COVID-19/diagnosis , CRISPR-Associated Proteins/genetics , Humans , Nucleic Acid Amplification Techniques/methods , RNA , Reproducibility of Results , SARS-CoV-2/genetics , Sensitivity and SpecificityABSTRACT
Zoom metalens doublets, featuring ultra-compactness, strong zoom capability, and CMOS compatibility, exhibit unprecedented advantages over the traditional refractive zoom lens. However, the huge chromatic aberration narrows the working bandwidth, which limits their potential applications in broadband systems. Here, by globally optimizing the phase profiles in the visible, we designed and numerically demonstrated a moiré lens based zoom metalens doublet that can achromatically work in the band of 440-640â nm. Such a doublet can achieve a continuous zoom range from 1× to 10×, while also maintaining a high focusing efficiency up to 86.5% and polarization insensitivity.
ABSTRACT
BACKGROUND: TaqMan probe-based real-time PCR (qPCR/RT-qPCR) has been widely used in various fields because of its high sensitivity and specificity. However, TaqMan probes are associated with a relatively higher background signal, and hence negatively affect the detection results. METHODS: Double-stranded probes (DSPs) were designed for the high sensitive detection of hepatitis B virus (HBV) DNA and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA using qPCR/RT-qPCR. Old DSPs (ODSPs) consist of different lengths of positive and negative strands with complementary oligonucleotides. We systematically optimized ODSPs length, the free energy of hybridization (ΔG) between complementary oligonucleotides, and the length of sticky ends, and the novel DSPs performances were evaluated in comparison with other types of probes. RESULTS: By using similar length positive and negative strands, controlling ΔG between complementary oligonucleotides to approximately -30 kcal/mol, and maintaining the sticky end length at 4-6 nt, the analytical performances of DSPs were significantly improved. Compared with other types of probes, DSPs are advantageous in fluorescence signal intensity and sensitivity. CONCLUSION: DSPs can further improve the detection sensitivity and the detection rate of low-concentration samples in molecular diagnosis.
Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnosis , Humans , Oligonucleotides , RNA, Viral/analysis , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction/methods , SARS-CoV-2/genetics , Sensitivity and SpecificityABSTRACT
Accurately predicting the binding affinity of protein-ligand pairs is an essential part of drug discovery. Since wet laboratory experiments to determine the binding affinity are expensive and time-consuming, several computational methods for binding affinity prediction have been proposed. In the representation of compounds, most methods only focus on the structural properties such as SMILES and ignore the bioactive properties. In this study, we proposed a novel model named PLA-MoRe to predict protein-ligand binding affinity, which represents compounds based on both structural and bioactive properties and mainly contains three feature extractors. First, a structure feature extractor based on the graph isomorphism network was constructed to learn the representations of the molecular graphs. Second, we designed an Autoencoder-based bioactive feature extractor to integrate the multisource bioactive information including chemical, target, network, cellular, and clinical. The above two parts aimed to learn representations of compounds in terms of structures and bioactivities, respectively. Then, we constructed a sequence feature extractor to learn embeddings for protein sequences. The output of the three extractors was concatenated and fed into a fully connected network for affinity prediction. We compared PLA-MoRe with three state-of-the-art methods, and an ablation study was conducted to test the role of each part of the model. Further attention visualization showed that our model had the potential to locate the binding sites, which might help explain the mechanism of interaction. These results prove that PLA-MoRe is competitive and reliable. The resource codes are freely available at the GitHub repository https://github.com/QingyuLiaib/PLA-MoRe.
Subject(s)
Polyesters , Proteins , Amino Acid Sequence , Binding Sites , Ligands , Proteins/chemistryABSTRACT
Microorganisms residing in the human respiratory tract can be exhaled, and they constitute a part of environmental microbiotas. However, the expiratory microbiota community and its associations with environmental microbiotas remain poorly understood. Here, expiratory bacteria and fungi and the corresponding microbiotas from the living environments were characterized by DNA amplicon sequencing of residents' exhaled breath condensate (EBC) and environmental samples collected from 14 residences in Nanjing, China. The microbiotas of EBC samples, with a substantial heterogeneity, were found to be as diverse as those of skin, floor dust, and airborne microbiotas. Model fitting results demonstrated the role of stochastic processes in the assembly of the expiratory microbiota. Using a fast expectation-maximization algorithm, microbial community analysis revealed that expiratory microbiotas were differentially associated with other types of microbiotas in a type-dependent and residence-specific manner. Importantly, the expiratory bacteria showed a composition similarity with airborne bacteria in the bathroom and kitchen environments with an average of 12.60%, while the expiratory fungi showed a 53.99% composition similarity with the floor dust fungi. These differential patterns indicate different relationships between expiratory microbiotas and the airborne microbiotas and floor dust microbiotas. The results here illustrated for the first time the associations between expiratory microbiotas and indoor microbiotas, showing a potential microbial exchange between the respiratory tract and indoor environment. Thus, improved hygiene and ventilation practices can be implemented to optimize the indoor microbial exposome, especially in indoor bathrooms and kitchens.