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1.
Cell ; 187(9): 2129-2142.e17, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38670071

RESUMO

Interspecies blastocyst complementation (IBC) provides a unique platform to study development and holds the potential to overcome worldwide organ shortages. Despite recent successes, brain tissue has not been achieved through IBC. Here, we developed an optimized IBC strategy based on C-CRISPR, which facilitated rapid screening of candidate genes and identified that Hesx1 deficiency supported the generation of rat forebrain tissue in mice via IBC. Xenogeneic rat forebrain tissues in adult mice were structurally and functionally intact. Cross-species comparative analyses revealed that rat forebrain tissues developed at the same pace as the mouse host but maintained rat-like transcriptome profiles. The chimeric rate of rat cells gradually decreased as development progressed, suggesting xenogeneic barriers during mid-to-late pre-natal development. Interspecies forebrain complementation opens the door for studying evolutionarily conserved and divergent mechanisms underlying brain development and cognitive function. The C-CRISPR-based IBC strategy holds great potential to broaden the study and application of interspecies organogenesis.


Assuntos
Prosencéfalo , Animais , Prosencéfalo/metabolismo , Prosencéfalo/embriologia , Camundongos , Ratos , Blastocisto/metabolismo , Feminino , Sistemas CRISPR-Cas/genética , Transcriptoma , Organogênese , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Masculino , Camundongos Endogâmicos C57BL
2.
Cell ; 181(3): 590-603.e16, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32272060

RESUMO

Conversion of glial cells into functional neurons represents a potential therapeutic approach for replenishing neuronal loss associated with neurodegenerative diseases and brain injury. Previous attempts in this area using expression of transcription factors were hindered by the low conversion efficiency and failure of generating desired neuronal types in vivo. Here, we report that downregulation of a single RNA-binding protein, polypyrimidine tract-binding protein 1 (Ptbp1), using in vivo viral delivery of a recently developed RNA-targeting CRISPR system CasRx, resulted in the conversion of Müller glia into retinal ganglion cells (RGCs) with a high efficiency, leading to the alleviation of disease symptoms associated with RGC loss. Furthermore, this approach also induced neurons with dopaminergic features in the striatum and alleviated motor defects in a Parkinson's disease mouse model. Thus, glia-to-neuron conversion by CasRx-mediated Ptbp1 knockdown represents a promising in vivo genetic approach for treating a variety of disorders due to neuronal loss.


Assuntos
Neurogênese/fisiologia , Neuroglia/metabolismo , Células Ganglionares da Retina/metabolismo , Animais , Sistemas CRISPR-Cas/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Modelos Animais de Doenças , Dopamina/metabolismo , Regulação da Expressão Gênica/genética , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças do Sistema Nervoso/metabolismo , Neurônios/metabolismo , Doença de Parkinson/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Células Ganglionares da Retina/fisiologia
3.
J Biol Chem ; : 107556, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39002683

RESUMO

Diversity, a hallmark of G protein-coupled receptor (GPCR) signaling, partly stems from alternative splicing of a single gene generating more than one isoform for a receptor. Additionally, receptor responses to ligands can be attenuated by desensitization upon prolonged or repeated ligand exposure. Both phenomena have been demonstrated and exemplified by the deuterostome tachykinin (TK) signaling system, although the role of phosphorylation in desensitization remains a subject of debate. Here, we describe the signaling system for tachykinin-related peptides (TKRPs) in a protostome, mollusk Aplysia. We cloned the Aplysia TKRP precursor, which encodes three TKRPs (apTKRP-1, apTKRP-2a, and apTKRP-2b) containing the FXGXR-amide motif. In situ hybridization and immunohistochemistry showed predominant expression of TKRP mRNA and peptide in the cerebral ganglia. TKRPs and their post-translational modifications were observed in extracts of CNS ganglia using mass spectrometry. We identified two Aplysia TKRP receptors (TKRPRs), named apTKRPR-A and apTKRPR-B. These receptors are two isoforms generated through alternative splicing of the same gene and differ only in their intracellular C-termini. Structure-activity relationship analysis of apTKRP-2b revealed that both C-terminal amidation and conserved residues of the ligand are critical for receptor activation. C-terminal truncates and mutants of apTKRPRs suggested that there is a C-terminal phosphorylation-independent desensitization for both receptors. Moreover, apTKRPR-B also exhibits phosphorylation-dependent desensitization through the phosphorylation of C-terminal Ser/Thr residues. This comprehensive characterization of the Aplysia TKRP signaling system underscores the evolutionary conservation of the TKRP and TK signaling systems, while highlighting the intricacies of receptor regulation through alternative splicing and differential desensitization mechanisms.

4.
Genome Res ; 32(2): 228-241, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35064006

RESUMO

The pathogenesis of COVID-19 is still elusive, which impedes disease progression prediction, differential diagnosis, and targeted therapy. Plasma cell-free RNAs (cfRNAs) carry unique information from human tissue and thus could point to resourceful solutions for pathogenesis and host-pathogen interactions. Here, we performed a comparative analysis of cfRNA profiles between COVID-19 patients and healthy donors using serial plasma. Analyses of the cfRNA landscape, potential gene regulatory mechanisms, dynamic changes in tRNA pools upon infection, and microbial communities were performed. A total of 380 cfRNA molecules were up-regulated in all COVID-19 patients, of which seven could serve as potential biomarkers (AUC > 0.85) with great sensitivity and specificity. Antiviral (NFKB1A, IFITM3, and IFI27) and neutrophil activation (S100A8, CD68, and CD63)-related genes exhibited decreased expression levels during treatment in COVID-19 patients, which is in accordance with the dynamically enhanced inflammatory response in COVID-19 patients. Noncoding RNAs, including some microRNAs (let 7 family) and long noncoding RNAs (GJA9-MYCBP) targeting interleukin (IL6/IL6R), were differentially expressed between COVID-19 patients and healthy donors, which accounts for the potential core mechanism of cytokine storm syndromes; the tRNA pools change significantly between the COVID-19 and healthy group, leading to the accumulation of SARS-CoV-2 biased codons, which facilitate SARS-CoV-2 replication. Finally, several pneumonia-related microorganisms were detected in the plasma of COVID-19 patients, raising the possibility of simultaneously monitoring immune response regulation and microbial communities using cfRNA analysis. This study fills the knowledge gap in the plasma cfRNA landscape of COVID-19 patients and offers insight into the potential mechanisms of cfRNAs to explain COVID-19 pathogenesis.


Assuntos
COVID-19 , Ácidos Nucleicos Livres , RNA/sangue , COVID-19/sangue , COVID-19/genética , Ácidos Nucleicos Livres/sangue , Síndrome da Liberação de Citocina , Humanos , SARS-CoV-2
5.
Nature ; 571(7764): 275-278, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31181567

RESUMO

Recently developed DNA base editing methods enable the direct generation of desired point mutations in genomic DNA without generating any double-strand breaks1-3, but the issue of off-target edits has limited the application of these methods. Although several previous studies have evaluated off-target mutations in genomic DNA4-8, it is now clear that the deaminases that are integral to commonly used DNA base editors often bind to RNA9-13. For example, the cytosine deaminase APOBEC1-which is used in cytosine base editors (CBEs)-targets both DNA and RNA12, and the adenine deaminase TadA-which is used in adenine base editors (ABEs)-induces site-specific inosine formation on RNA9,11. However, any potential RNA mutations caused by DNA base editors have not been evaluated. Adeno-associated viruses are the most common delivery system for gene therapies that involve DNA editing; these viruses can sustain long-term gene expression in vivo, so the extent of potential RNA mutations induced by DNA base editors is of great concern14-16. Here we quantitatively evaluated RNA single nucleotide variations (SNVs) that were induced by CBEs or ABEs. Both the cytosine base editor BE3 and the adenine base editor ABE7.10 generated tens of thousands of off-target RNA SNVs. Subsequently, by engineering deaminases, we found that three CBE variants and one ABE variant showed a reduction in off-target RNA SNVs to the baseline while maintaining efficient DNA on-target activity. This study reveals a previously overlooked aspect of off-target effects in DNA editing and also demonstrates that such effects can be eliminated by engineering deaminases.


Assuntos
DNA/genética , Edição de Genes/métodos , Mutagênese , Mutação , Nucleosídeo Desaminases/genética , Engenharia de Proteínas , RNA/genética , Adenina/metabolismo , Aminoidrolases/genética , Aminoidrolases/metabolismo , Citosina/metabolismo , Citosina Desaminase/genética , Citosina Desaminase/metabolismo , Células HEK293 , Humanos , Nucleosídeo Desaminases/metabolismo , Especificidade por Substrato , Transfecção
6.
Inhal Toxicol ; 36(2): 100-105, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38368594

RESUMO

OBJECTIVE: The gram-negative bacterial cell wall component endotoxin (lipopolysaccharide, LPS) is a key component of particulate matter (PM). PM exposure is associated with cardiovascular morbidity and mortality. However, the contribution of individual components of PM to acute and chronic cardiovascular measures is not clear. This study examines whether systemic inflammation induced by LPS inhalation causes acute changes in cardiovascular physiology measures. MATERIALS AND METHODS: In this double blinded, placebo-controlled crossover study, fifteen adult volunteers underwent inhalation exposure to 20,000 EU Clinical Center Reference Endotoxin (CCRE). Peripheral blood and induced sputum neutrophils were obtained at baseline and six hours post-exposure. Blood pressure, measures of left ventricular function (ejection fraction (LVEF) and global longitudinal strain (LVGLS)), and indices of endothelial function (flow mediated dilation (FMD) and velocity time integral during hyperemia (VTIhyp)) were measured before and after treatment. Wilcoxon sign-rank tests and linear mixed models were used for statistical analysis. RESULTS: In comparison with normal saline, LPS inhalation resulted in significant increases in peripheral blood and sputum neutrophils but was not associated with significant alterations in blood pressure, LVGLS, LVEF, FMD, or VTIhyp. DISCUSSION AND CONCLUSIONS: In healthy adults, systemic inflammation after LPS inhalation was not associated with acute changes in cardiovascular physiology. Larger studies are needed to investigate the effects of other PM components on inflammation induced cardiovascular dysfunction.


Assuntos
Endotoxinas , Neutrófilos , Adulto , Humanos , Endotoxinas/toxicidade , Lipopolissacarídeos/toxicidade , Estudos Cross-Over , Inflamação , Material Particulado
7.
Nucleic Acids Res ; 50(3): e15, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-34792175

RESUMO

Recombineering assisted multiplex genome editing generally uses single-stranded oligonucleotides for site directed mutational changes. It has proven highly efficient for functional screens and to optimize microbial cell factories. However, this approach is limited to relatively small mutational changes. Here, we addressed the challenges involved in the use of double-stranded DNA substrates for multiplex genome engineering. Recombineering is mediated by phage single-strand annealing proteins annealing ssDNAs into the replication fork. We apply this insight to facilitate the generation of ssDNA from the dsDNA substrate and to alter the speed of replication by elevating the available deoxynucleoside triphosphate (dNTP) levels. Intracellular dNTP concentration was elevated by ribonucleotide reductase overexpression or dNTP addition to establish double-stranded DNA Recombineering-assisted Multiplex Genome Engineering (dReaMGE), which enables rapid and flexible insertional and deletional mutagenesis at multiple sites on kilobase scales in diverse bacteria without the generation of double-strand breaks or disturbance of the mismatch repair system. dReaMGE can achieve combinatorial genome engineering works, for example, alterations to multiple biosynthetic pathways, multiple promoter or gene insertions, variations of transcriptional regulator combinations, within a few days. dReaMGE adds to the repertoire of bacterial genome engineering to facilitate discovery, functional genomics, strain optimization and directed evolution of microbial cell factories.


Assuntos
DNA , Engenharia Genética , Bactérias/genética , DNA de Cadeia Simples/genética , Genoma Bacteriano/genética , Oligonucleotídeos/genética
8.
Biochem Genet ; 62(1): 504-529, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37386336

RESUMO

Although immunotherapy is a valuable treatment for gastric cancer (GC), identifying the patients who would benefit most from this approach presents a challenge. In this study, GC patients were divided into two subtypes by consensus clustering according to T cell-mediated tumor killing related genes (TTKRGs), and there were significant differences in tumor-infiltrating immune cells, signaling pathways, and gene expression of immunomodulators and inhibitory immune checkpoints between the two subtypes. Then, we developed an individualized signature based on TTKRGs, and its clinical and predictive value in GC patients for chemotherapeutic and immunotherapeutic responses was assessed. We confirmed the expression levels of signature genes in GC tumor tissue using quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, to improve the accuracy of GC prognosis predictions, we established a nomogram. We further identified some compounds as sensitive drugs targeting GC risk groups. The signature showed significant predictive ability across RNA-seq, microarray, and qRT-PCR cohorts, which could assist in predicting survival, immunotherapeutic and chemotherapeutic outcomes in GC patients.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Prognóstico , Linfócitos T , Análise por Conglomerados , RNA-Seq
9.
Folia Biol (Praha) ; 70(1): 74-83, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38830125

RESUMO

Chlamydia psittaci pneumonia (CPP) is a lung disease caused by the infection with the Chla-mydia psittaci bacterium, which can lead to severe acute respiratory distress syndrome and systemic symptoms. This study explored the specific mechanisms underlying the impact of reactive oxygen species (ROS) on the Th17/Treg balance in CPP. The levels of ROS and the differentiation ratio of Th17/Treg in the peripheral blood of healthy individuals and CPP patients were measured using ELISA and flow cytometry, respectively. The association between the ROS levels and Th17/Treg was assessed using Pearson correlation analysis. The ROS levels and the Th17/Treg ratio were measured in CD4+ T cells following H2O2 treatment and NLRP3 inhibition. The effects of H2O2 treatment and NLRP3 inhibition on the NLRP3/IL-1ß/caspase-1 pathway were observed using immunoblotting. Compared to the healthy group, the CPP group exhibited increased levels of ROS in the peripheral blood, an elevated ratio of Th17 differentiation, and a decreased ratio of Treg differentiation. ROS levels were positively correlated with the Th17 cell proportion but negatively correlated with the Treg cell proportion. The ROS levels and NLRP3/IL-1ß/caspase-1 expression were up-regulated in CD4+ T cells after H2O2 treatment. Furthermore, there was an increase in Th17 differentiation and a decrease in Treg differentiation. Conversely, the NLRP3/IL-1ß/caspase-1 pathway inhibition reversed the effects of H2O2 treatment, with no significant change in the ROS levels. ROS regulates the Th17/Treg balance in CPP, possibly through the NLRP3/IL-1ß/caspase-1 pathway. This study provides a new perspective on the development of immunotherapy for CPP.


Assuntos
Caspase 1 , Diferenciação Celular , Chlamydophila psittaci , Interleucina-1beta , Proteína 3 que Contém Domínio de Pirina da Família NLR , Espécies Reativas de Oxigênio , Linfócitos T Reguladores , Células Th17 , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Linfócitos T Reguladores/imunologia , Caspase 1/metabolismo , Diferenciação Celular/efeitos dos fármacos , Interleucina-1beta/metabolismo , Transdução de Sinais , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Peróxido de Hidrogênio/metabolismo , Psitacose
10.
J Allergy Clin Immunol ; 151(6): 1577-1584.e4, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36708816

RESUMO

BACKGROUND: Rhinoviruses (RVs) are the most common trigger for asthma exacerbations, and there are currently no targeted therapies for viral-induced asthma exacerbations. RV infection causes neutrophilic inflammation, which is often resistant to effects of glucocorticoids. IL-1 receptor antagonist (IL-1RA) treatment reduces neutrophilic inflammation in humans challenged with inhaled endotoxin and thus may have therapeutic potential for RV-induced asthma exacerbations. OBJECTIVE: We sought to test the hypothesis that IL-1RA treatment of airway epithelium reduces RV-mediated proinflammatory cytokine production, which is important for neutrophil recruitment. METHODS: Human bronchial epithelial cells from deceased donors without prior pulmonary disease were cultured at air-liquid interface and treated with IL-13 to approximate an asthmatic inflammatory milieu. Human bronchial epithelial cells were infected with human RV-16 with or without IL-1RA treatment. RESULTS: RV infection promoted the release of IL-1α and the neutrophil-attractant cytokines IL-6, IL-8, and CXCL10. Proinflammatory cytokine secretion was significantly reduced by IL-1RA treatment without significant change in IFN-ß release or RV titer. In addition, IL-1RA reduced MUC5B expression after RV infection without impacting MUC5AC. CONCLUSIONS: These data suggest that IL-1RA treatment significantly reduced proinflammatory cytokines while preserving the antiviral response. These results provide evidence for further investigation of IL-1RA as a novel targeted therapy against neutrophil-attractant cytokine release in RV-induced airway inflammatory responses.


Assuntos
Asma , Infecções por Enterovirus , Infecções por Picornaviridae , Humanos , Rhinovirus/fisiologia , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Receptores de Interleucina-1 , Asma/tratamento farmacológico , Citocinas/metabolismo , Epitélio/metabolismo , Células Epiteliais/metabolismo , Inflamação/tratamento farmacológico , Infecções por Picornaviridae/tratamento farmacológico
11.
Int J Mol Sci ; 25(3)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38339148

RESUMO

Pseudomonas aeruginosa is a clinically challenging pathogen due to its high resistance to antibiotics. Quorum sensing inhibitors (QSIs) have been proposed as a promising strategy to overcome this resistance by interfering with the bacterial communication system. Among the potential targets of QSIs, PqsR is a key regulator of quorum sensing in Pseudomonas aeruginosa. However, the current research on PqsR inhibitors is limited by the lack of diversity in the chemical structures and the screening methods. Therefore, this study aims to develop a multidimensional screening model for PqsR inhibitors based on both ligand- and receptor-based approaches. First, a pharmacophore model was constructed from a training set of PqsR inhibitors to identify the essential features and spatial arrangement for the activity. Then, molecular docking and dynamics simulations were performed to explore the core interactions between PqsR inhibitors and their receptor. The results indicate that an effective PqsR inhibitor should possess two aromatic rings, one hydrogen bond acceptor, and two hydrophobic groups and should form strong interactions with the following four amino acid residues: TYR_258, ILE_236, LEU_208, and GLN_194. Moreover, the docking score and the binding free energy should be lower than -8 kcal/mol and -40 kcal/mol, respectively. Finally, the validity of the multidimensional screening model was confirmed by a test set of PqsR inhibitors, which showed a higher accuracy than the existing screening methods based on single characteristics. This multidimensional screening model would be a useful tool for the discovery and optimization of PqsR inhibitors in the future.


Assuntos
Simulação de Dinâmica Molecular , Farmacóforo , Simulação de Acoplamento Molecular , Percepção de Quorum , Antibacterianos/química
12.
J Biol Chem ; 298(10): 102440, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36049520

RESUMO

The protostome leucokinin (LK) signaling system, including LK peptides and their G protein-coupled receptors, has been characterized in several species. Despite the progress, molecular mechanisms governing LK peptide-receptor interactions remain to be elucidated. Previously, we identified a precursor protein for Aplysia leucokinin-like peptides (ALKs) that contains the greatest number of amidated peptides among LK precursors in all species identified so far. Here, we identified the first ALK receptor from Aplysia, ALKR. We used cell-based IP1 activation assays to demonstrate that two ALK peptides with the most copies, ALK1 and ALK2, activated ALKR with high potencies. Other endogenous ALK-derived peptides bearing the FXXWX-amide motif also activated ALKR to various degrees. Our examination of cross-species activity of ALKs with the Anopheles LK receptor was consistent with a critical role for the FXXWX-amide motif in receptor activity. Furthermore, we showed, through alanine substitution of ALK1, the highly conserved phenylalanine (F), tryptophan (W), and C-terminal amidation were each essential for receptor activation. Finally, we used an artificial intelligence-based protein structure prediction server (Robetta) and Autodock Vina to predict the ligand-bound conformation of ALKR. Our model predicted several interactions (i.e., hydrophobic interactions, hydrogen bonds, and amide-pi stacking) between ALK peptides and ALKR, and several of our substitution and mutagenesis experiments were consistent with the predicted model. In conclusion, our results provide important information defining possible interactions between ALK peptides and their receptors. The workflow utilized here may be useful for studying other ligand-receptor interactions for a neuropeptide signaling system, particularly in protostomes.


Assuntos
Aplysia , Inteligência Artificial , Neuropeptídeos , Receptores de Neuropeptídeos , Animais , Amidas , Aplysia/genética , Aplysia/metabolismo , Ligantes , Mutagênese , Neuropeptídeos/química , Neuropeptídeos/genética , Conformação Proteica , Receptores de Neuropeptídeos/química , Receptores de Neuropeptídeos/genética
13.
Nat Prod Rep ; 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37873660

RESUMO

Covering: 2005 to August, 2023Polyamine-containing natural products (NPs) have been isolated from a wide range of terrestrial and marine organisms and most of them exhibit remarkable and diverse activities, including antimicrobial, antiprotozoal, antiangiogenic, antitumor, antiviral, iron-chelating, anti-depressive, anti-inflammatory, insecticidal, antiobesity, and antioxidant properties. Their extraordinary activities and potential applications in human health and agriculture attract increasing numbers of studies on polyamine-containing NPs. In this review, we summarized the source, structure, classification, bioactivities and biosynthesis of polyamine-containing NPs, focusing on the biosynthetic mechanism of polyamine itself and representative polyamine alkaloids, polyamine-containing siderophores with catechol/hydroxamate/hydroxycarboxylate groups, nonribosomal peptide-(polyketide)-polyamine (NRP-(PK)-PA), and NRP-PK-long chain poly-fatty amine (lcPFAN) hybrid molecules.

14.
Anal Chem ; 95(35): 13101-13112, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37526338

RESUMO

A new lateral flow immunoassay strip (LFIA) combining sensitive detection and identification of multiple bacteria remains a huge challenge. In this study, we first developed multifunctional urchin-shaped Au-Ag@Pt nanoparticles (UAA@P NPs) with a unique combination of colorimetric-SERS-photothermal-catalytic (CM/SERS/PT/CL) properties and integrated them with LFIA for multiplexed detection and specific discrimination of pathogenic bacteria in blood samples. Unlike the conventional LFIA that relied on antibody (Ab), this novel LFIA introduced 4-mercaptophenylboronic acid (4-MPBA) as an ideal Ab replacer that was functionalized on UAA@P NPs (UAA@P/M NPs) with outstanding binding and enrichment capacities toward bacteria. Taking Staphylococcus aureus (S. aureus) as model bacteria, the limit of detection (LOD) was 3 CFU/mL for SERS-LFIA, 27 CFU/mL for PT-LFIA, and 18 CFU/mL for CL-LFIA, three of which were over 330-fold, 37-fold, and 55-fold more sensitive than ordinary visual CM-LFIA, respectively. Besides, this SERS-LFIA is capable of identifying three types of bacterial spiked blood samples (E. coli, S. aureus, and P. aeruginosa) effectively according to specific bacterial Raman "fingerprints" by partial least-squares-discriminant analysis (PLS-DA). More importantly, this LFIA was successfully applied to blood samples with satisfactory recoveries from 90.3% to 108.8% and capable of identifying the infected patients (N = 4) from healthy subjects (N = 2) with great accuracy. Overall, the multimodal LFIA incorporates bacteria discrimination and quantitative detection, offering an avenue for early warning and diagnosis of bacterial infection.


Assuntos
Infecções Bacterianas , Nanopartículas Metálicas , Humanos , Escherichia coli , Staphylococcus aureus , Imunoensaio , Bactérias , Anticorpos , Infecções Bacterianas/diagnóstico , Limite de Detecção , Nanopartículas Metálicas/química , Ouro/química
15.
Anal Chem ; 95(14): 5955-5966, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36916246

RESUMO

Ultra-sensitive detection of cancer-related biomarkers in serum is of great significance for early diagnosis, treatment, prognosis, and staging of cancer. In this work, we proposed a surface-enhanced Raman scattering and fluorescence (SERS/FL) dual-mode biosensor for hepatocellular carcinoma (HCC)-related miRNA (miR-224) detection using the composition of well-arranged Au nanoarrays (Au NAs) substrate coupled with the target-catalyzed hairpin assembly (CHA) strategy. The hot spots densely and uniformly distributed on the Au array offers considerably enhanced and reproducible SERS signals, along with their wide and open surface to facilitate miR-224 adsorption. By this sensing strategy, the target miR-224 can be detected in a wide linear range (1 fM to 1 nM) with a limit of detection of 0.34 fM in the SERS mode and 0.39 fM in the FL mode. Meanwhile, this biosensor with exceptional specificity and anti-interference ability can discriminate target miR-224 from other interference miRNAs. Practical analysis of human blood samples also demonstrated considerable reliability and repeatability of our developed strategy. Furthermore, this biosensor can distinguish HCC cancer subjects from normal ones and monitor HCC patients before and after hepatectomy as well as guide the distinct Barcelona clinic liver cancer (BCLC) stages. Overall, benefiting from a well-arranged Au nanoarray, CHA amplification strategy, and SERS/metal enhanced fluorescence effect, this established biosensor opens new avenues for the early prediction, warning, monitoring, and staging of HCC.


Assuntos
Técnicas Biossensoriais , Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanopartículas Metálicas , MicroRNAs , Humanos , Carcinoma Hepatocelular/diagnóstico , Ouro/química , Limite de Detecção , Neoplasias Hepáticas/diagnóstico , Nanopartículas Metálicas/química , Nanoestruturas , Reprodutibilidade dos Testes , Análise Espectral Raman , Corantes Fluorescentes/química
16.
Mol Genet Genomics ; 298(4): 823-836, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37059908

RESUMO

Coronavirus 2019 (COVID-19) is a complex disease that affects billions of people worldwide. Currently, effective etiological treatment of COVID-19 is still lacking; COVID-19 also causes damages to various organs that affects therapeutics and mortality of the patients. Surveillance of the treatment responses and organ injury assessment of COVID-19 patients are of high clinical value. In this study, we investigated the characteristic fragmentation patterns and explored the potential in tissue injury assessment of plasma cell-free DNA in COVID-19 patients. Through recruitment of 37 COVID-19 patients, 32 controls and analysis of 208 blood samples upon diagnosis and during treatment, we report gross abnormalities in cfDNA of COVID-19 patients, including elevated GC content, altered molecule size and end motif patterns. More importantly, such cfDNA fragmentation characteristics reflect patient-specific physiological changes during treatment. Further analysis on cfDNA tissue-of-origin tracing reveals frequent tissue injuries in COVID-19 patients, which is supported by clinical diagnoses. Hence, our work demonstrates and extends the translational merit of cfDNA fragmentation pattern as valuable analyte for effective treatment monitoring, as well as tissue injury assessment in COVID-19.


Assuntos
COVID-19 , Ácidos Nucleicos Livres , Humanos , COVID-19/diagnóstico , Ácidos Nucleicos Livres/genética
17.
Biometrics ; 79(2): 1145-1158, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35146750

RESUMO

An estimated quadratic inference function method is proposed for correlated failure time data with auxiliary covariates. The proposed method makes efficient use of the auxiliary information for the incomplete exposure covariates and preserves the property of the quadratic inference function method that requires the covariates to be completely observed. It can improve the estimation efficiency and easily deal with the situation when the cluster size is large. The proposed estimator which minimizes the estimated quadratic inference function is shown to be consistent and asymptotically normal. A chi-squared test based on the estimated quadratic inference function is proposed to test hypotheses about the regression parameters. The small-sample performance of the proposed method is investigated through extensive simulation studies. The proposed method is then applied to analyze the Study of Left Ventricular Dysfunction (SOLVD) data as an illustration.


Assuntos
Interpretação Estatística de Dados , Simulação por Computador
18.
Dig Dis Sci ; 68(7): 3009-3017, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36961670

RESUMO

BACKGROUND: The incidence of gastric cancer has long been at a high level in China, seriously affecting the health of Chinese people. AIMS: This case‒control study was performed to identify gene methylation biomarkers of gastric cancer susceptibility. METHODS: A total of 393 gastric cancer cases and 397 controls were included in this study. Gene methylation in peripheral blood leukocytes was detected by a methylation-sensitive high-resolution melting method, and the Helicobacter pylori antibody presence was semi-quantified in serum by ELISA. RESULTS: Individuals with total methylation of CDKN2B/P15 had a 1.883-fold (95%CI: 1.166-3.040, P = 0.010) risk of gastric cancer compared with unmethylated individuals. Individuals with both CDKN2B/P15 and NEUROG1 methylation had a higher risk of gastric cancer (OR = 2.147, 95% CI: 1.137-4.073, P = 0.019). The interaction between CDKN2B/P15 and NEUROG1 total methylation on gastric cancer risk was affected by the pattern of adjustment. In addition, the joint effects between CDKN2B/P15 total methylation and environmental factors, such as freshwater fish intake (OR = 6.403, 95% CI = 2.970-13.802, P < 0.001), irregular diet (OR = 5.186, 95% CI = 2.559-10.510, P < 0.001), unsanitary water intake (OR = 2.238, 95% CI = 1.144-4.378, P = 0.019), smoking (OR = 2.421, 95% CI = 1.456-4.026, P = 0.001), alcohol consumption(OR = 2.163, 95% CI = 1.309-3.576, P = 0.003), and garlic intake(OR = 0.373, 95% CI = 0.196-0.709, P = 0.003) on GC risk were observed, respectively. However, CDKN2B/P15 and NEUROG1 total methylation were not associated with gastric cancer prognosis. CONCLUSION: CDKN2B/P15 methylation in peripheral blood may be a potential biomarker for evaluating susceptibility to gastric cancer. The joint effects between CDKN2B/P15 methylation and environmental factors may also contribute to gastric cancer susceptibility.


Assuntos
Metilação de DNA , Neoplasias Gástricas , Humanos , Biomarcadores , Estudos de Casos e Controles , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Neoplasias Gástricas/etiologia , Neoplasias Gástricas/genética
19.
Eur Arch Otorhinolaryngol ; 280(2): 839-845, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36066668

RESUMO

OBJECTIVES: The aim of this study was to investigate the relationship between matrix metalloproteinase-7 (MMP-7) expression and the clinical and pathological characteristics of salivary adenoid cystic carcinomas (SACC) of the palatal minor salivary gland. METHODS: In this study, 58 samples of SACC and 10 samples of normal salivary gland tissue were examined. Immunohistochemistry was used to detect MMP-7 and vascular endothelial growth factor A (VEGF-A) expression in SACC and normal tissues. The clinical and pathological characteristics of the patients with SACC were collected. RESULTS: Of the 58 SACC samples, 44 were positive for MMP-7, and the expression rate was 75.9%. No expression was detected in the 10 normal salivary gland tissues. The level of MMP-7 expression in the SACC and normal samples was significantly different. The level of expression of MMP-7 in the SACC samples did not correlate with age, sex or pathological type but did correlate with pathological grade, nerve infiltration and clinical stage. There was a positive correlation between VEGF-A and MMP-7 expression. CONCLUSIONS: The SACC samples showed high expression of MMP-7, which was associated with tumour differentiation, invasiveness and clinical stage. The detection of MMP-7 positively correlated with the detection of VEGF-A in SACC.


Assuntos
Carcinoma Adenoide Cístico , Metaloproteinase 7 da Matriz , Neoplasias das Glândulas Salivares , Humanos , Carcinoma Adenoide Cístico/patologia , Linhagem Celular Tumoral , Metaloproteinase 7 da Matriz/metabolismo , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares Menores/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
J Hand Surg Am ; 48(4): 407.e1-407.e11, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35131113

RESUMO

PURPOSE: We performed a systematic review and meta-analysis to determine an optimal rehabilitation protocol following surgical repair for flexor tendon injury in zone II of the hand. METHODS: Records from PubMed, Embase, and Cochrane were retrieved from their establishment to January 12, 2020. Seven studies were included in the final analysis. A total of 569 digits with a flexor tendon injury in zone II of the hand were included in this meta-analysis: 135 in a place and hold group; 161 in an active flexion and extension group; and 273 in an early passive motion group. RESULTS: There was no significant difference between the place and hold and early passive motion regimes in the incidence of rupture. There was a significant difference between the active flexion and extension and early passive motion regimes in the incidence of rupture. In the early active motion group, the possibility of 1 or more grades of improvement on the Strickland grading system was increased. CONCLUSIONS: The early active motion group obtained greater total active motion than the early passive motion group. A higher risk of rupture was noted in the active flexion and extension subgroup repaired by 2-strand core suture. The 2-strand technique was not sufficient for active flexion and extension protocols. Further study in multistrand tendon repair technique with early active exercise in zone II should be undertaken to determine its efficacy. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Assuntos
Traumatismos dos Dedos , Traumatismos dos Tendões , Humanos , Traumatismos dos Dedos/cirurgia , Traumatismos dos Tendões/cirurgia , Tendões/cirurgia , Ruptura , Extremidade Superior , Amplitude de Movimento Articular
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