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1.
J Neural Eng ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38986468

RESUMO

OBJECTIVE: Electroencephalography (EEG) is widely recognized as an effective method for detecting fatigue. However, practical applications of EEG for fatigue detection in real-world scenarios are often challenging, particularly in cases involving subjects not included in the training datasets, owing to bio-individual differences and noisy labels. This study aims to develop an effective framework for cross-subject fatigue detection by addressing these challenges. APPROACH: In this study, we propose a novel framework, termed DP-MP, for cross-subject fatigue detection, which utilizes a Domain-Adversarial Neural Network (DANN)-based prototypical representation in conjunction with Mix-up pairwise learning. Our proposed DP-MP framework aims to mitigate the impact of bio-individual differences by encoding fatigue-related semantic structures within EEG signals and exploring shared fatigue prototype features across individuals. Notably, to the best of our knowledge, this work is the first to conceptualize fatigue detection as a pairwise learning task, thereby effectively reducing the interference from noisy labels. Furthermore, we propose the Mix-up pairwise learning (MixPa) approach in the field of fatigue detection, which broadens the advantages of pairwise learning by introducing more diverse and informative relationships among samples. RESULTS: Cross-subject experiments were conducted on two benchmark databases, SEED-VIG and FTEF, achieving state-of-the-art performance with average accuracies of 88.14% and 97.41%, respectively. These promising results demonstrate our model's effectiveness and excellent generalization capability. SIGNIFICANCE: This is the first time EEG-based fatigue detection has been conceptualized as a pairwise learning task, offering a novel perspective to this field. Moreover, our proposed DP-MP framework effectively tackles the challenges of bio-individual differences and noisy labels in the fatigue detection field and demonstrates superior performance. Our work provides valuable insights for future research, promoting the application of brain-computer interfaces for fatigue detection in real-world scenarios. .

2.
Chem Commun (Camb) ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007923

RESUMO

O-GlcNAcase (OGA) is implicated in several important biological and disease-relevant processes. Here, we synthesized fluorogenic probes for OGA by grafting GlcNAc directly or using a self-immolative linker to the hydroxyl position of 4-hydroxylisoindoline (BHID), a typical excited-state intramolecular proton transfer (ESIPT) probe. The probe was used for a fluorogenic assay to determine the half maximal inhibitory concentration of a known OGA inhibitor and differentiate between OGA and hexosaminidase when GlcNAc is replaced by GlcNPr, where a propionyl group is used instead of an acetyl group.

3.
Cardiology ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38437799

RESUMO

INTRODUCTION: Amyloidosis caused by TTR mutations (ATTRv) is a rare inherited and autosomal dominant disease. More than 150 mutants of TTR have been reported, whereas some of them remain to be investigated. METHODS: A 52-year-old male presented with heart failure and clinically diagnosed ATTR cardiac amyloidosis (ATTR-CA) was recruited. Whole exome sequencing (WES) was performed. Biochemical and biophysical experiments characterized protein stability using urea-mediated tryptophan fluorescence. Drug response was analyzed by fibril formation assay. Finally, tetramer TTR concentration in patient' serum sample was measured by ultra-performance liquid chromatography (UPLC). RESULTS: For the proband, whole exome sequencing revealed a mutation (c.200G>T; p.Gly67Val and referred to as G47V) in TTR gene. Biochemical and biophysical kinetics study showed that the thermodynamic stability of G47V-TTR (Cm = 2.4 M) was significantly lower than that of WT-TTR (Cm = 3.4 M) and comparable to that of L55P-TTR (Cm = 2.3 M), an early age-of-onset mutation. G47V:WT-TTR heterozygous tetramers kinetic stability (t1/2 = 1.4 h) was further compromised compared to that of the homozygous G47V-TTR (t1/2 = 3.1 h). Among three small molecule stabilizers, AG10 exhibited the best inhibition of the fibrillation of G47V-TTR homozygous protein. Using a UPLC assay, nearly 40% of TTR in this patient was calculated to be non-tetrameric. CONCLUSION: In this work, we reported a patient presented early onset of clinically typical ATTR-CM due to G47V-TTR mutation. Our work not only for the first time characterized the biochemical properties of G47V-TTR mutation, but also provided hints for the pathogenicity of this mutation.

4.
Chem Rev ; 124(5): 2699-2804, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38422393

RESUMO

The ability to gain spatiotemporal information, and in some cases achieve spatiotemporal control, in the context of drug delivery makes theranostic fluorescent probes an attractive and intensely investigated research topic. This interest is reflected in the steep rise in publications on the topic that have appeared over the past decade. Theranostic fluorescent probes, in their various incarnations, generally comprise a fluorophore linked to a masked drug, in which the drug is released as the result of certain stimuli, with both intrinsic and extrinsic stimuli being reported. This release is then signaled by the emergence of a fluorescent signal. Importantly, the use of appropriate fluorophores has enabled not only this emerging fluorescence as a spatiotemporal marker for drug delivery but also has provided modalities useful in photodynamic, photothermal, and sonodynamic therapeutic applications. In this review we highlight recent work on theranostic fluorescent probes with a particular focus on probes that are activated in tumor microenvironments. We also summarize efforts to develop probes for other applications, such as neurodegenerative diseases and antibacterials. This review celebrates the diversity of designs reported to date, from discrete small-molecule systems to nanomaterials. Our aim is to provide insights into the potential clinical impact of this still-emerging research direction.


Assuntos
Corantes Fluorescentes , Medicina de Precisão , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Fluorescência , Nanomedicina Teranóstica
5.
BMC Plant Biol ; 24(1): 157, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38424498

RESUMO

BACKGROUND: D-type cyclins (CYCD) regulate the cell cycle G1/S transition and are thus closely involved in cell cycle progression. However, little is known about their functions in rice. RESULTS: We identified 14 CYCD genes in the rice genome and confirmed the presence of characteristic cyclin domains in each. The expression of the OsCYCD genes in different tissues was investigated. Most OsCYCD genes were expressed at least in one of the analyzed tissues, with varying degrees of expression. Ten OsCYCD proteins could interact with both retinoblastoma-related protein (RBR) and A-type cyclin-dependent kinases (CDKA) forming holistic complexes, while OsCYCD3;1, OsCYCD6;1, and OsCYCD7;1 bound only one component, and OsCYCD4;2 bound to neither protein. Interestingly, all OsCYCD genes except OsCYCD7;1, were able to induce tobacco pavement cells to re-enter mitosis with different efficiencies. Transgenic rice plants overexpressing OsCYCD2;2, OsCYCD6;1, and OsCYCD7;1 (which induced cell division in tobacco with high-, low-, and zero-efficiency, respectively) were created. Higher levels of cell division were observed in both the stomatal lineage and epidermal cells of the OsCYCD2;2- and OsCYCD6;1-overexpressing plants, with lower levels seen in OsCYCD7;1-overexpressing plants. CONCLUSIONS: The distinct expression patterns and varying effects on the cell cycle suggest different functions for the various OsCYCD proteins. Our findings will enhance understanding of the CYCD family in rice and provide a preliminary foundation for the future functional verification of these genes.


Assuntos
Ciclinas , Oryza , Ciclinas/genética , Ciclinas/metabolismo , Oryza/genética , Oryza/metabolismo , Fosforilação , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Ciclo Celular/genética , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Mitose
6.
Chem Sci ; 15(2): 757-764, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38179535

RESUMO

Drug-induced liver injury (DILI) is the most common cause for acute liver failure in the USA and Europe. However, most of DILI cases can recover or be prevented if treatment by the offending drug is discontinued. Recent research indicates that peroxynitrite (ONOO-) can be a potential indicator to diagnose DILI at an early stage. Therefore, the establishment of an assay to detect and track ONOO- in DILI cases is urgently needed. Here, a FRET-based ratiometric nano fluorescent probe CD-N-I was developed to detect ONOO- with high selectivity and excellent sensitivity. This probe consists of carbon dots and a naphthalimide-isatin peroxynitrite sensing system assembled based on electrostatic interactions. Using CD-N-I we were able to detect exogenous ONOO- in live cells and endogenous ONOO- in APAP-induced liver injury of HepG2 cells.

7.
Plants (Basel) ; 13(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38256728

RESUMO

Salt stress is one of the most important factors limiting rice growth and yield increase. Salt tolerance of rice at the bud burst (STB) stage determines whether germinated seeds can grow normally under salt stress, which is very important for direct seeding. However, reports on quantitative trait loci (QTLs) and candidate genes for STB in rice are very limited. In this study, a natural population of 130 indica and 81 japonica rice accessions was used to identify STB-related QTLs and candidate genes using a genome-wide association study (GWAS). Nine QTLs, including five for relative shoot length (RSL), two for relative root length (RRL), and two for relative root number (RRN), were identified. Five of these STB-related QTLs are located at the same site as the characterized salt tolerance genes, such as OsMDH1, OsSRFP1, and OsCDPK7. However, an important QTL related to RSL, qRSL1-2, has not been previously identified and was detected on chromosome 1. The candidate region for qRSL1-2 was identified by linkage disequilibrium analysis, 18 genes were found to have altered expression levels under salt stress through the RNA-seq database, and 10 of them were found to be highly expressed in the shoot. It was also found that, eight candidate genes (LOC_Os01g62980, LOC_Os01g63190, LOC_Os01g63230, LOC_Os01g63280, LOC_Os01g63400, LOC_Os01g63460, and LOC_Os01g63580) for qRSL1-2 carry different haplotypes between indica and japonica rice, which exactly corresponds to the significant difference in RSL values between indica and japonica rice in this study. Most of the accessions with elite haplotypes were indica rice, which had higher RSL values. These genes with indica-japonica specific haplotypes were identified as candidate genes. Rice accessions with elite haplotypes could be used as important resources for direct seeding. This study also provides new insights into the genetic mechanism of STB.

8.
Acad Radiol ; 31(2): 605-616, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37586940

RESUMO

RATIONALE AND OBJECTIVES: This study aimed to develop and validate a magnetic resonance imaging (MRI)-based radiomics nomogram combining radiomics signatures and clinical factors to differentiate between benign and malignant vertebral compression fractures (VCFs). MATERIALS AND METHODS: A total of 189 patients with benign VCFs (n = 112) or malignant VCFs (n = 77) were divided into training (n = 133) and validation (n = 56) cohorts. Radiomics features were extracted from MRI T1-weighted images and short-TI inversion recovery images to develop the radiomics signature, and the Rad score was constructed using least absolute shrinkage and selection operator regression. Demographic and MRI morphological characteristics were assessed to build a clinical factor model using multivariate logistic regression analysis. A radiomics nomogram was constructed based on the Rad score and independent clinical factors. Finally, the diagnostic performance of the radiomics nomogram, clinical model, and radiomics signature was validated using receiver operating characteristic and decision curve analysis (DCA). RESULTS: Six features were used to build a combined radiomics model (combined-RS). Pedicle or posterior element involvement, paraspinal mass, and fluid sign were identified as the most important morphological factors for building the clinical factor model. The radiomics signature was superior to the clinical model in terms of the area under the curve (AUC), accuracy, and specificity. The radiomics nomogram integrating the combined-RS, pedicle or posterior element involvement, paraspinal mass, and fluid sign achieved favorable predictive efficacy, generating AUCs of 0.92 and 0.90 in the training and validation cohorts, respectively. The DCA indicated good clinical usefulness of the radiomics nomogram. CONCLUSION: The MRI-based radiomics nomogram, combining the radiomics signature and clinical factors, showed favorable predictive efficacy for differentiating benign from malignant VCFs.


Assuntos
Fraturas por Compressão , Fraturas da Coluna Vertebral , Humanos , Radiômica , Fraturas por Compressão/diagnóstico por imagem , Nomogramas , Fraturas da Coluna Vertebral/diagnóstico por imagem , Imageamento por Ressonância Magnética , Estudos Retrospectivos
9.
Talanta ; 270: 125526, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38091748

RESUMO

Logic gate-based fluorescent probes are powerful tools for the discriminative sensing of multiple signaling molecules that are expressed in concert during the progression of many diseases such as inflammation, cancer, aging, and other disorders. To achieve logical sensing, multiple functional groups are introduced to the different substitution sites of a single fluorescent dye, which increases the complexity of chemical synthesis. Herein, we report a simple strategy that incorporates just one responsive unit into a hemicyanine dye achieving the logic gate-based sensing of two independent analytes. We introduce boronic acid to hemicyanine to quench the fluorescence, and in the presence of hydrogen peroxide (H2O2), the fluorescence is recovered due to removal of the boronate. Interestingly, the subsequent decrease in pH turned the red fluorescence of hemicyanine to green emissive because of protonation of the phenolic alcohol. This unique feature of the probe enables us to construct "INHIBIT" and "AND" logical gates for the accurate measuring of intracellular H2O2 and acidic pH in tandem. This study offers insight into the simple construction of logic-gate based fluorescent probes for the tandem sensing of multiple analytes that are correlatively produced during disease progression.


Assuntos
Corantes Fluorescentes , Peróxido de Hidrogênio , Corantes Fluorescentes/química , Carbocianinas/química , Concentração de Íons de Hidrogênio
10.
Circulation ; 149(8): 605-626, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38018454

RESUMO

BACKGROUND: A better understanding of the molecular mechanism of aortic valve development and bicuspid aortic valve (BAV) formation would significantly improve and optimize the therapeutic strategy for BAV treatment. Over the past decade, the genes involved in aortic valve development and BAV formation have been increasingly recognized. On the other hand, ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) gene family members have been reported to be able to modulate cardiovascular development and diseases. The present study aimed to further investigate the roles of ADAMTS family members in aortic valve development and BAV formation. METHODS: Morpholino-based ADAMTS family gene-targeted screening for zebrafish heart outflow tract phenotypes combined with DNA sequencing in a 304 cohort BAV patient registry study was initially carried out to identify potentially related genes. Both ADAMTS gene-specific fluorescence in situ hybridization assay and genetic tracing experiments were performed to evaluate the expression pattern in the aortic valve. Accordingly, related genetic mouse models (both knockout and knockin) were generated using the CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeat-associated 9) method to further study the roles of ADAMTS family genes. The lineage-tracing technique was used again to evaluate how the cellular activity of specific progenitor cells was regulated by ADAMTS genes. Bulk RNA sequencing was used to investigate the signaling pathways involved. Inducible pluripotent stem cells derived from both BAV patients and genetic mouse tissue were used to study the molecular mechanism of ADAMTS. Immunohistochemistry was performed to examine the phenotype of cardiac valve anomalies, especially in the extracellular matrix components. RESULTS: ADAMTS genes targeting and phenotype screening in zebrafish and targeted DNA sequencing on a cohort of patients with BAV identified ADAMTS16 (a disintegrin and metalloproteinase with thrombospondin motifs 16) as a BAV-causing gene and found the ADAMTS16 p. H357Q variant in an inherited BAV family. Both in situ hybridization and genetic tracing studies described a unique spatiotemporal pattern of ADAMTS16 expression during aortic valve development. Adamts16+/- and Adamts16+/H355Q mouse models both exhibited a right coronary cusp-noncoronary cusp fusion-type BAV phenotype, with progressive aortic valve thickening associated with raphe formation (fusion of the commissure). Further, ADAMTS16 deficiency in Tie2 lineage cells recapitulated the BAV phenotype. This was confirmed in lineage-tracing mouse models in which Adamts16 deficiency affected endothelial and second heart field cells, not the neural crest cells. Accordingly, the changes were mainly detected in the noncoronary and right coronary leaflets. Bulk RNA sequencing using inducible pluripotent stem cells-derived endothelial cells and genetic mouse embryonic heart tissue unveiled enhanced FAK (focal adhesion kinase) signaling, which was accompanied by elevated fibronectin levels. Both in vitro inducible pluripotent stem cells-derived endothelial cells culture and ex vivo embryonic outflow tract explant studies validated the altered FAK signaling. CONCLUSIONS: Our present study identified a novel BAV-causing ADAMTS16 p. H357Q variant. ADAMTS16 deficiency led to BAV formation.


Assuntos
Doença da Válvula Aórtica Bicúspide , Cardiopatias Congênitas , Doenças das Valvas Cardíacas , Humanos , Animais , Camundongos , Peixe-Zebra/genética , Doenças das Valvas Cardíacas/metabolismo , Células Endoteliais/metabolismo , Desintegrinas/genética , Desintegrinas/metabolismo , Hibridização in Situ Fluorescente , Valva Aórtica/metabolismo , Cardiopatias Congênitas/complicações , Matriz Extracelular/metabolismo , Trombospondinas/metabolismo , Metaloproteases/metabolismo , Proteínas ADAMTS/genética , Proteínas ADAMTS/metabolismo
13.
Ecotoxicol Environ Saf ; 266: 115532, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37806131

RESUMO

Benzene poisoning can cause acute myeloid leukemia (AML) through a variety of passways. Tim-3 has gained prominence as a potential candidate in mediating immunosuppression in tumor microenvironments. The macrophage polarization is also related to immune escape. Herein, we reported that Tim-3 and macrophage M2 polarization play a vital role in benzene-induced AML. First, the benzene-induced AML C3H/He mouse model was constructed by subcutaneously injecting 250 mg/kg of benzene. After six months, macrophage phenotype, cytokines, and Tim-3 expression levels were investigated. Flow cytometry assay revealed that the T-cell inhibitory receptor Tim-3 was significantly upregulated in both bone marrow and spleen of the benzene-induced AML mouse model. Elisa's results displayed a decreased serum level of IL-12 while increased TGF-ß1. Mechanistically, changes in cytokine secretion promote the growth of M2-type macrophages in the bone marrow and spleen, as determined by immunofluorescence assay. The increased levels of PI3K, AKT, and mTOR in the benzene-exposure group further proved the crucial role of Tim-3 in regulating the functional status of macrophages in the AML microenvironment. These results demonstrate that Tim-3 and macrophage polarization may play a vital role during the immune escape of the benzene-induced AML. This study provides a new potential intervention site for immune checkpoint-based AML therapeutic strategy.


Assuntos
Benzeno , Receptor Celular 2 do Vírus da Hepatite A , Leucemia Mieloide Aguda , Animais , Camundongos , Benzeno/toxicidade , Benzeno/metabolismo , Modelos Animais de Doenças , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Leucemia Mieloide Aguda/induzido quimicamente , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Macrófagos/metabolismo , Camundongos Endogâmicos C3H , Microambiente Tumoral
14.
BMC Cardiovasc Disord ; 23(1): 399, 2023 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-37568094

RESUMO

OBJECTIVES: Long QT syndrome (LQTS) is one of the primary causes of sudden cardiac death (SCD) in youth. Studies have identified mutations in ion channel genes as key players in the pathogenesis of LQTS. However, the specific etiology in individual families remains unknown. METHODS: Three unrelated Chinese pedigrees diagnosed with LQTS or Jervell and Lange-Nielsen syndrome (JLNS) were recruited clinically. Whole exome sequencing (WES) was performed and further validated by multiplex ligation-dependent probe amplification (MLPA) and Sanger sequencing. RESULTS: All of the probands in our study experienced syncope episodes and featured typically prolonged QTc-intervals. Two probands also presented with congenital hearing loss and iron-deficiency anemia and thus were diagnosed with JLNS. A total of five different variants in KCNQ1, encoding a subunit of the voltage-gated potassium channel, were identified in 3 probands. The heterozygous variants, KCNQ1 c.749T > C was responsible for LQTS in Case 1, transmitting in an autosomal dominant pattern. Two patterns of compound heterozygous variants were responsible for JLNS, including a large deletion causing loss of the exon 16 and missense variant c.1663 C > T in Case 2, and splicing variant c.605-2 A > G and frame-shift variant c.1265del in Case 3. To our knowledge, the compound heterozygous mutations containing a large deletion and missense variant were first reported in patients with JLNS. CONCLUSION: Our study expanded the LQTS genetic spectrum, thus favoring disease screening and diagnosis, personalized treatment, and genetic consultation.


Assuntos
Síndrome de Jervell-Lange Nielsen , Síndrome do QT Longo , Adolescente , Humanos , Síndrome de Jervell-Lange Nielsen/diagnóstico , Síndrome de Jervell-Lange Nielsen/genética , Canal de Potássio KCNQ1/genética , Síndrome do QT Longo/diagnóstico , Síndrome do QT Longo/genética , Mutação , Éxons , Mutação de Sentido Incorreto , Linhagem
15.
Chem Sci ; 14(28): 7762-7769, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37476709

RESUMO

Inspired by natural enzymes that possess multiple catalytic activities, here we develop a bifunctional metal-organic frame-work (MOF) for biosensing applications. Ultrasmall gold nano-particles (AuNPs) are grown in the internal cavities of an iron (Fe) porphyrin-based MOF to produce a hybridized nanozyme, AuNPs@PCN-224(Fe), in which AuNPs and PCN-224(Fe) exhibit the catalytic activity of glucose oxidase (GOx) and horseradish peroxidase (HRP), respectively. We established that the bifunctional nanozyme was capable of a cascade reaction to generate hydrogen peroxide in the presence of d-glucose and oxygen in situ, and subsequently activate a colorimetric or chemiluminescent substrate through HRP-mimicking catalytic activity. The nanozyme was selective over a range of other saccharides, and 93% of the catalytic activity was retained after being recycled five times.

16.
J Am Chem Soc ; 145(31): 17377-17388, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37497917

RESUMO

The five-year survival rate of hepatocellular carcinoma (HCC) remains unsatisfactory. This reflects, in part, the paucity of effective methods that allow the target-specific diagnosis and therapy of HCC. Here, we report a strategy based on engineered human serum albumin (HSA) that permits the HCC-targeted delivery of diagnostic and therapeutic agents. Covalent cysteine conjugation combined with the exploitation of host-guest chemistry was used to effect the orthogonal functionalization of HSA with two functionally independent peptides. One of these peptides targets glypican-3 (GPC-3), an HCC-specific biomarker, while the second reduces macrophage phagocytosis through immune-checkpoint stimulation. This orthogonally engineered HSA proved effective for the GPC-3-targeted delivery of near-infrared fluorescent and phototherapeutic agents, thus permitting target-specific optical visualization and photodynamic ablation of HCC in vivo. This study thus offers new insights into specificity-enhanced fluorescence-guided surgery and phototherapy of HCC through the orthogonal engineering of biocompatible proteins.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/metabolismo , Carcinoma Hepatocelular/terapia , Fototerapia/métodos , Albuminas , Albumina Sérica Humana , Macrófagos/metabolismo , Fagocitose
17.
Chem Commun (Camb) ; 59(53): 8278-8281, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37318211

RESUMO

A nitroreductase (NTR) responsive fluorescent probe with long wavelength fluorescence emission was used to determine the NTR activity of a selection of bacterial species under a range of different bacterial growth conditions ensuring applicability under multiple complex clinical environments, where sensitivity, reaction time, and the detection accuracy were suitable for planktonic cultures and biofilms.


Assuntos
Corantes Fluorescentes , Nitrorredutases , Microscopia de Fluorescência
18.
Org Biomol Chem ; 21(22): 4661-4666, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37212349

RESUMO

Peroxynitrite (ONOO-) is an important oxygen/nitrogen reactive species implicated in a number of physiological and pathological processes. However, due to the complexity of the cellular micro-environment, the sensitive and accurate detection of ONOO- remains a challenging task. Here, we developed a long-wavelength fluorescent probe based on the conjugation between a TCF scaffold and phenylboronate; the resulting conjugate is capable of supramolecular host-guest assembly with human serum albumin (HSA) for the fluorogenic sensing of ONOO-. The probe exhibited an enhanced fluorescence over a low concentration range of ONOO- (0-9.6 µM), whist the fluorescence was quenched when the concentration of ONOO- exceeded 9.6 µM. In addition, when human serum albumin (HSA) was added, the initial fluorescence of the probe was significantly enhanced, which enabled the more sensitive detection of low-concentrations of ONOO- in aqueous buffer solution and in cells. The molecular structure of the supramolecular host-guest ensemble was determined using small-angle X-ray scattering.


Assuntos
Corantes Fluorescentes , Ácido Peroxinitroso , Humanos , Ácido Peroxinitroso/química , Corantes Fluorescentes/química , Espécies Reativas de Oxigênio , Estrutura Molecular , Limite de Detecção
20.
J Am Chem Soc ; 145(16): 8917-8926, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37040584

RESUMO

Chemical tools capable of classifying multidrug-resistant bacteria (superbugs) can facilitate early-stage disease diagnosis and help guide precision therapy. Here, we report a sensor array that permits the facile phenotyping of methicillin-resistant Staphylococcus aureus (MRSA), a clinically common superbug. The array consists of a panel of eight separate ratiometric fluorescent probes that provide characteristic vibration-induced emission (VIE) profiles. These probes bear a pair of quaternary ammonium salts in different substitution positions around a known VIEgen core. The differences in the substituents result in varying interactions with the negatively charged cell walls of bacteria. This, in turn, dictates the molecular conformation of the probes and affects their blue-to-red fluorescence intensity ratios (ratiometric changes). Within the sensor array, the differences in the ratiometric changes for the probes result in "fingerprints" for MRSA of different genotypes. This allows them to be identified using principal component analysis (PCA) without the need for cell lysis and nucleic acid isolation. The results obtained with the present sensor array agree well with those obtained using polymerase chain reaction (PCR) analysis.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Genótipo , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia , Antibacterianos
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