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1.
Int J Biol Macromol ; 269(Pt 2): 132279, 2024 Jun.
Article En | MEDLINE | ID: mdl-38734344

Aptasensors for detection of ochratoxin A (OTA) have been extensively studied, but the majority of them require costly and large-scale equipment as signal readers. Herein, a photothermal aptasensor capable of portable detection of OTA through a thermometer was developed on basis of aptamer structural switching and rolling circle amplification (RCA)-enriched DNAzyme. Oligonucleotides and alkaline phosphatase (ALP) modified magnetic beads were prepared. The binding of aptamers to OTA led to the release of ALP labeled complementary DNA. After magnetic separation, ALP catalyzed the padlock dephosphorylation, inhibiting the subsequent RCA reaction. This process converted the OTA concentration into the amount of the photothermal reagent oxTMB produced from the catalytic reaction induced by RCA-enriched DNAzyme. Under the optimal conditions, the detection limit (LOD) of this aptasensor was 2.28 nM in a clean buffer, while the LOD reached 2.43 nM in 2 % grape juice. The good performance of the photothermal aptasensor makes it possible to measure OTA pollution in low resource environments.


Aptamers, Nucleotide , Biosensing Techniques , DNA, Catalytic , Fruit and Vegetable Juices , Limit of Detection , Nucleic Acid Amplification Techniques , Ochratoxins , Vitis , Ochratoxins/analysis , DNA, Catalytic/chemistry , DNA, Catalytic/metabolism , Aptamers, Nucleotide/chemistry , Nucleic Acid Amplification Techniques/methods , Fruit and Vegetable Juices/analysis , Biosensing Techniques/methods , Vitis/chemistry , Food Contamination/analysis
2.
Phys Chem Chem Phys ; 26(19): 14364-14373, 2024 May 15.
Article En | MEDLINE | ID: mdl-38712391

Using density functional theory calculations we investigate the formation, structure and electronic properties of gh-C3N4-supported Ni-Co (Ni-Co/gh-C3N4) dual-atom catalysts and Ni1(Co1) single-metal catalysts, as a paradigmatic example of single-atom versus few-atom catalysts. An inverted mold assumption is proposed to identify the factors determining the number, shape and packing manner of metal atoms inside the pores of gh-C3N4. The area matching between virtual fragments and metal fillers and lattice inheritance from N coordination and metal aggregates allow for a stable Ni-Co/gh-C3N4, which would possess more active sites and a more complex structure-activity relation than single-atom doping. The hydrogen production behavior and catalytic activity of this catalyst are comprehensively discussed. Ni-Co/gh-C3N4 exhibits higher hydrogen evolution activity than Ni1(Co1)/gh-C3N4 at an appropriate H coverage, which is comparable to Pt under analogous conditions. This strategy, derived from the inverted mold assumption, is deemed to be a simple and easy-to-operate method for designing and building metal aggregates confined inside the pores of two-dimensional materials and in the cavities of nanoparticles for few-atom catalysts.

3.
Adv Sci (Weinh) ; : e2401269, 2024 May 17.
Article En | MEDLINE | ID: mdl-38757665

Tumor microenvironment (TME) plays an important role in the tumor progression. Among TME components, cancer-associated fibroblasts (CAFs) show multiple tumor-promoting effects and can induce tumor immune evasion and drug-resistance. Regulating CAFs can be a potential strategy to augment systemic anti-tumor immunity. Here, the study observes that hydrogen treatment can alleviate intracellular reactive oxygen species of CAFs and reshape CAFs' tumor-promoting and immune-suppressive phenotypes. Accordingly, a controllable and TME-responsive hydrogen therapy based on a CaCO3 nanoparticles-coated magnesium system (Mg-CaCO3) is developed. The hydrogen therapy by Mg-CaCO3 can not only directly kill tumor cells, but also inhibit pro-tumor and immune suppressive factors in CAFs, and thus augment immune activities of CD4+ T cells. As implanted in situ, Mg-CaCO3 can significantly suppress tumor growth, turn the "cold" primary tumor into "hot", and stimulate systematic anti-tumor immunity, which is confirmed by the bilateral tumor transplantation models of "cold tumor" (4T1 cells) and "hot tumor" (MC38 cells). This hydrogen therapy system reverses immune suppressive phenotypes of CAFs, thus providing a systematic anti-tumor immune stimulating strategy by remodeling tumor stromal microenvironment.

4.
Article En | MEDLINE | ID: mdl-38757680

Human moral reactions to artificial intelligence (AI) agents' behavior constitute an important aspect of modern-day human-AI relationships. Although previous studies have mainly focused on autonomy ethics, this study investigates how individuals judge AI agents' violations of community ethics (including betrayals and subversions) compared with human violations. Participants' behavioral responses, event-related potentials (ERPs), and individual differences were assessed. Behavioral findings reveal that participants rated AI agents' community-violating actions less morally negative than human transgressions, possibly because AI agents are commonly perceived as having less agency than human adults. The ERP N1 component showed the same pattern with moral rating scores, indicating the modulation effect of human-AI differences on initial moral intuitions. Moreover, the level of social withdrawal correlated with a smaller N1 in the human condition but not in the AI condition. The N2 and P2 components were sensitive to the difference between the loyalty/betrayal and authority/subversion domains but not human/AI differences. Individual levels of moral sense and autistic traits also influenced behavioral data, especially on the loyalty/betrayal domain. In our opinion, these findings offer insights for predicting moral responses to AI agents and guiding ethical AI development aligned with human moral values.

5.
J Hazard Mater ; 473: 134600, 2024 May 12.
Article En | MEDLINE | ID: mdl-38759409

Microbiologically induced calcite precipitation (MICP), as a newly developing bioremediation technology, could redeem heavy metal contamination in diverse scenarios. In this study, MICP bacterium Sporosarcina ureilytica ML-2 was employed to suppress the pollution of Pb, Cd and Zn in municipal sludge nutrient soil. After MICP remediation, the exchangeable Cd and Zn in sludge nutrient soil were correspondingly reduced by 31.02 % and 6.09 %, while the carbonate-bound Pb, Cd and Zn as well as the residual fractions were increased by 16.12 %, 6.63 %, 13.09 % and 6.10 %, 45.70 %, 3.86 %, respectively. In addition, the extractable Pb, Cd and Zn either by diethylenetriaminepentaacetic acid (DTPA) or toxicity characteristic leaching procedure (TCLP) in sludge nutrient soil were significantly reduced. These results demonstrated that the bio-calcite generated via MICP helped to immobilize heavy metals. Furthermore, MICP treatment improved the abundance of functional microorganisms related to urea cycle, while reduced the overall abundance of metal resistance genes (MRGs) and antibiotic resistance genes (ARGs). This work confirmed the feasibility of MICP in remediation of heavy metal in sludge nutrient soil, which expanded the application field of MICP and provided a promising way for heavy metal pollution management.

6.
Women Health ; 64(5): 440-449, 2024.
Article En | MEDLINE | ID: mdl-38755523

Female-specific reproductive factors might contribute to increased risk of cardiovascular disease, and the American Heart Association (AHA) recently proposed Life's Essential 8 (LE8) score to quantify cardiovascular health (CVH). The study aimed to examine the relationships between reproductive factors and the LE8 score among post-menopause women in the United States. We enrolled 3223 post-menopause women from National Health and Nutrition Examination Survey (NHANES). CVH groups based on LE8 score were low (0-49), moderate (50-79), and high good CVH levels (80-100). Multivariate ordinal logistic regressions were applied to estimate the associations between reproductive factors and the LE8 score. In multivariate model, early menarche (OR: 0.69, 95 percent CI: 0.51-0.93) and early menopause (OR: 0.57, 95 percent CI: 0.43-0.77) were associated with LE8 score compared with normal menarche and menopause; Meanwhile, ages at menarche and menopause were positively correlated with LE8 score. The number of pregnancies and full-term pregnancies were negatively associated with LE8 (OR for per pregnancy increase and 95 percent CI, 0.93 (0.88, 0.98), 0.93 (0.87, 0.99), separately). Overall, natural menopausal women with early age at menarche and menopause, and a higher number of pregnancies may have a high risk of lower CVH, and need to focus on their CVH.


Cardiovascular Diseases , Menarche , Menopause , Nutrition Surveys , Postmenopause , Humans , Female , Middle Aged , Cardiovascular Diseases/epidemiology , Postmenopause/physiology , United States/epidemiology , Menopause/physiology , Risk Factors , Aged , Cross-Sectional Studies , Reproductive History , Pregnancy , Logistic Models , Age Factors
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 318: 124517, 2024 May 23.
Article En | MEDLINE | ID: mdl-38801790

The effects of common migration substances in milk packaging on digestive protease were studied. We choose the common migrants found in eight types of multi-layer composite milk packaging. Enzyme activity experiments revealed that pepsin activity decreased by approximately 18 % at 500 µg/mL of stearic acid and stearamide treatment, while trypsin activity decreased by approximately 18 % only by stearic acid treatment (500 µg/mL). Subsequently, fluorescence spectroscopy, circular dichroism spectroscopy, and molecular docking technology were employed to investigate the inhibition mechanism of protease activity by migrating substances in three systems: stearic acid-trypsin, stearic acid-pepsin, and stearamide-pepsin. Results showed that the inhibitory effect of stearic acid on trypsin is a reversible mixed inhibition, whereas the inhibitory effects of stearic acid and stearamide on pepsin are non-competitive. In all three systems, ΔH < 0, ΔS < 0, and ΔG < 0, indicating the binding process between the migrant and the protease is a spontaneous exothermic process primarily driven by hydrogen bonding and van der Waals forces. In addition, their binding constants are all around 104 L/moL, indicating that there are moderate binding affinities exist between migrants and proteases. The binding process results in the quenching of the protease's endogenous fluorescence and induces alterations in the enzyme's secondary structure. Synchronized fluorescence spectroscopy showed that stearic acid enhanced the hydrophobicity near the Tyr residue of trypsin. The molecular docking results indicated that the binding affinity of stearic acid-trypsin, stearic acid-pepsin, and stearamide-pepsin was -22.51 kJ/mol, -12.35 kJ/mol, -19.28 kJ/mol respectively, which consistent with the trend in the enzyme activity results. This study can provide references for the selection of milk packaging materials and the use of processing additives, ensuring food health and safety.

8.
Talanta ; 276: 126145, 2024 Apr 26.
Article En | MEDLINE | ID: mdl-38723473

Due to the common contamination of multiple mycotoxins in food, which results in stronger toxicity, it is particularly important to simultaneously test for various mycotoxins for the protection of human health. In this study, a disposable immunosensor array with low-cost was designed and fabricated using cellulose paper, polydimethylsiloxane (PDMS), and semiconducting single-walled carbon nanotubes (s-SWCNTs), which was modified with specific antibodies for mycotoxins AFB1 and FB1 detection. The strategy for fabricating the immunosensor array with two individual channels involved a two-step protocol starting with the form of two kinds of carbon films by depositing single-wall carbon nanotubes (SWCNTs) and s-SWCNTs on the cellulose paper as the conductive wire and sensing element, followed by the assembly of chemiresistive biosensor with SWCNTs strip as the wire and s-SWCNTs as the sensing element. After immobilizing AFB1-bovine serum albumin (AFB1-BSA) and FB1-bovine serum albumin (FB1-BSA) separately on the different sensing regions, the formation of mycotoxin-BSA-antibody immunocomplexes transfers to electrochemical signal, which would change with the different concentrations of free mycotoxins. Under optimal conditions, the immunosensor array achieved a limit of detection (LOD) of 0.46 pg/mL for AFB1 and 0.34 pg/mL for FB1 within a wide dynamic range from 1 pg/mL to 20 ng/mL. Furthermore, the AFB1 and FB1 spiked in the ground corn and wheat extracts were detected with satisfactory recoveries, demonstrating the excellent practicality of this established method for simultaneous detection of mycotoxins.

9.
Oral Dis ; 2024 May 02.
Article En | MEDLINE | ID: mdl-38696357

OBJECTIVE: This study aimed to clarify the relationship between FADD amplification and overexpression and the tumor immune microenvironment. METHODS: Immunohistochemical staining and bioanalysis were used to analyze the association between FADD expression in tumor cells and cells in tumor microenvironment. RNA-seq analysis was used to detect the differences in gene expression upon FADD overexpression. Flow cytometry and multicolor immunofluorescence staining (mIHC) were used to detect the differences in CD8+ T-cell infiltration in FADD-overexpressed cells or tumor tissues. RESULTS: Overexpression of FADD significantly promoted tumor growth. Cells with high FADD expression presented high expression of CD276 and FGFBP1 and low expression of proinflammatory factors (such as IFIT1-3 and CXCL8), which reduced the percentage of CD8+ T cells and created a "cold tumor" immune microenvironment, thus promoting tumor progression. In vivo and in vitro experiment confirmed that tumor tissues with excessive FADD expression exhibited CD8+ T-cell exclusion in the microenvironment. CONCLUSION: Our preliminary investigation has discovered the association between FADD expression and the immunosuppressive microenvironment in HNSCC. Due to the high frequent amplification of the chromosomal region 11q13.3, where FADD is located, targeting FADD holds promise for improving the immune-inactive state of tumors, subsequently inhibiting HNSCC tumor progression.

10.
Adv Sci (Weinh) ; : e2309992, 2024 May 22.
Article En | MEDLINE | ID: mdl-38774946

Radiotherapy demonstrates a synergistic effect with immunotherapy by inducing a transformation of "immune cold" tumors into "immune hot" tumors in triple negative breast cancer (TNBC). Nevertheless, the effectiveness of immunotherapy is constrained by low expression of tumor-exposed antigens, inadequate inflammation, and insufficient tumor infiltrating lymphocyte (TILs). To address this predicament, novel lutecium-based rare earth nanoparticles (RENPs) are synthesized with the aim of amplifying radiation effect and tumor immune response. The nanoprobe is characterized by neodymium-based down-conversion fluorescence, demonstrating robust photostability, biocompatibility, and targetability. The conjugation of RENPs with a CXCR4 targeted drug enables precise delineation of breast tumors using a near-infrared imaging system and improves radiation efficacy via lutetium-based radio-sensitizer in vivo. Furthermore, the study shows a notable enhancement of immune response through the induction of immunogenic cell death and recruitment of TILs, resulting in the inhibition of tumor progression both in vitro and in vivo models following the administration of nanoparticles. Hence, the novel multifunctional nanoprobes incorporating various lanthanide elements offer the potential for imaging-guided tumor delineation, radio-sensitization, and immune activation post-radiation, thus presenting an efficient radio-immunotherapeutic approach for TNBC.

11.
Food Chem ; 453: 139697, 2024 Sep 30.
Article En | MEDLINE | ID: mdl-38788652

Spiropidion developed by Syngenta shows high insecticidal and acaricidal activity against a wide range of sucking pests. In this study, according to the structure of spiropidion, two haptens were synthesized by introducing carboxyl groups from the ester group. After cell fusion, a monoclonal antibody (mAb 8B5) of spiropidion was obtained. The IC50 of the established heterologous indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) was 7.36 ng/mL, and its working range was 1.75-34.92 ng/mL. The average recoveries were 76.05-124.78% in the Yangtze River and citrus samples. Moreover, the ic-ELISA results of 15 citrus samples agreed well with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Overall, the established ic-ELISA could be applied for the spiropidion residue monitor in food and agricultural samples.


Antibodies, Monoclonal , Enzyme-Linked Immunosorbent Assay , Haptens , Pesticide Residues , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , Haptens/chemistry , Haptens/immunology , Animals , Pesticide Residues/analysis , Pesticide Residues/chemistry , Tandem Mass Spectrometry , Food Contamination/analysis , Mice, Inbred BALB C , Mice , Citrus/chemistry , Insecticides/chemistry , Insecticides/analysis
12.
Photodiagnosis Photodyn Ther ; : 104230, 2024 May 29.
Article En | MEDLINE | ID: mdl-38821236

BACKGROUND: Primary membranous nephropathy (PMN) patients may experience retinal microvascular changes. However, current diagnostic methods for PMN are not accurate in analyzing these modifications. In the present study, optical coherence tomography angiography (OCTA) was used for quantitative measurement of microvascular changes in the eyes of PMN patients. METHODS: A total of 26 patients with PMN and 26 healthy control (HC) were evaluated in this cross-sectional study. Optical coherence tomography (OCT) and OCTA were used to collect retinal thickness (RT) and microvascular parameters in the macula and optic disk in the superficial capillary plexus (SCP) of all subjects. Clinical data were collected from the PMN group. The OCT and OCTA data for PMN and HC group were compared, and the correlation between the OCTA and clinical data in the PMN group was determined. RESULTS: Vascular density (VD) and perfusion density (PD) in the macular area of the PMN group were significantly lower than those of the HC group, especially in the temporal quadrant. No significant difference in the foveal avascular zone (FAZ), optic disc microvascular parameters, RT, and retinal nerve fiber layer (RNFL) thickness was observed between the two groups. Correlation was noted between VD and PD in the macular area and clinical indicators, such as serum creatinine, serum urea nitrogen, 24-hour urine volume and urinary protein concentration. CONCLUSION: Microvascular alterations in PMN patients occurred before ocular symptoms. The present quantitative study proposed a measurement method for detecting early retinal vascular injury in PMN patients.

13.
Cancer Res ; 2024 May 08.
Article En | MEDLINE | ID: mdl-38718319

Metabolic reprogramming is a hallmark of cancer. In addition to metabolic alterations in the tumor cells, multiple other metabolically active cell types in the tumor microenvironment (TME) contribute to the emergence of a tumor-specific metabolic milieu. Here, we defined the metabolic landscape of the TME during progression of head and neck squamous cell carcinoma (HNSCC) by performing single-cell RNA sequencing (scRNA-seq) on 26 human patient specimens, including normal tissue, pre-cancerous lesions, early-stage cancer, advanced-stage cancer, lymph node metastases, and recurrent tumors. The analysis revealed substantial heterogeneity at the transcriptional, developmental, metabolic, and functional levels in different cell types. SPP1+ macrophages were identified as a pro-tumor and pro-metastatic macrophage subtype with high fructose and mannose metabolism, which was further substantiated by integrative analysis and validation experiments. An inhibitor of fructose metabolism reduced the proportion of SPP1+ macrophages, reshaped the immunosuppressive TME, and suppressed tumor growth. In conclusion, this work delineated the metabolic landscape of HNSCC at a single-cell resolution and identified fructose metabolism as a key metabolic feature of a pro-tumor macrophage subpopulation.

14.
Ecol Lett ; 27(5): e14415, 2024 May.
Article En | MEDLINE | ID: mdl-38712683

The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large-scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass-loss rates and stabilization factors of plant-derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy-to-degrade components accumulate during early-stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass-loss rates and stabilization, notably in colder locations. Using TBI improved mass-loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early-stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.


Plant Leaves , Carbon Cycle , Carbon/metabolism
15.
Immunology ; 2024 Apr 01.
Article En | MEDLINE | ID: mdl-38561001

Radiation-induced fibrosis (RIF) is a severe chronic complication of radiotherapy (RT) manifested by excessive extracellular matrix (ECM) components deposition within the irradiated area. The lung, heart, skin, jaw, pelvic organs and so on may be affected by RIF, which hampers body functions and quality of life. There is accumulating evidence suggesting that the immune microenvironment may play a key regulatory role in RIF. This article discussed the synergetic or antagonistic effects of immune cells and mediators in regulating RIF's development. Several potential preventative and therapeutic strategies for RIF were proposed based on the immunological mechanisms to provide clinicians with improved cognition and clinical treatment guidance.

16.
Zookeys ; 1196: 271-283, 2024.
Article En | MEDLINE | ID: mdl-38586078

A new species of pomatiopsid freshwater snail, Fenouiliaundata Chen & He, sp. nov., is described from Guangxi, China, based on morphological and molecular evidence. The new species can be distinguished from its congeners by the following combination of characters: shell with low, prosocline, rounded axial ribs and fine spiral striae, broader than high; aperture broader than shell height; radula with lateral teeth have only two or three faint, wavy ridges on inner side. A molecular analysis of partial mitochondrial COI and 16S DNA sequences supports the systematic position of the new taxon.

17.
MedComm (2020) ; 5(4): e520, 2024 Apr.
Article En | MEDLINE | ID: mdl-38576455

Ferroptosis has been confirmed to be associated with various diseases, but the relationship between ferroptosis and atherosclerosis (AS) remains unclear. Our research detailly clarified the roles of ferroptosis in three continuous and main pathological stages of AS respectively (injury of endothelial cells [ECs], adhesion of monocytes, and formation of foam cells). We confirmed that oxidized low-density lipoprotein (ox-LDL), the key factor in the pathogenesis of AS, strongly induced ferroptosis in ECs. Inhibition of ferroptosis repressed the adhesion of monocytes to ECs by inhibiting inflammation of ECs. Ferroptosis also participated in the formation of foam cells and lipids by regulating the cholesterol efflux of macrophages. Further research confirmed that ox-LDL repressedthe activity of glutathione peroxidase 4 (GPX4), the classic lipid peroxide scavenger. Treatment of a high-fat diet significantly induced ferroptosis in murine aortas and aortic sinuses, which was accompanied by AS lesions and hyperlipidemia. Treatment with ferroptosis inhibitors significantly reduced ferroptosis, hyperlipidemia, and AS lesion development. In conclusion, our research determined that ox-LDL induced ferroptosis by repressing the activity of GPX4. Antiferroptosis treatment showed promising treatment effects in vivo. Ferroptosis-associated indexes also showed promising diagnostic potential in AS patients.

18.
Appl Microbiol Biotechnol ; 108(1): 289, 2024 Apr 08.
Article En | MEDLINE | ID: mdl-38587649

Rumen microbial urease inhibitors have been proposed for regulating nitrogen emission and improving nitrogen utilization efficiency in ruminant livestock industry. However, studies on plant-derived natural inhibitors of rumen microbial urease are limited. Urease accessory protein UreG, plays a crucial role in facilitating urease maturation, is a new target for design of urease inhibitor. The objective of this study was to select the potential effective inhibitor of rumen microbial urease from major protoberberine alkaloids in Rhizoma Coptidis by targeting UreG. Our results showed that berberine chloride and epiberberine exerted superior inhibition potential than other alkaloids based on GTPase activity study of UreG. Berberine chloride inhibition of UreG was mixed type, while inhibition kinetics type of epiberberine was uncompetitive. Furthermore, epiberberine was found to be more effective than berberine chloride in inhibiting the combination of nickel towards UreG and inducing changes in the second structure of UreG. Molecular modeling provided the rational structural basis for the higher inhibition potential of epiberberine, amino acid residues in G1 motif and G3 motif of UreG formed interactions with D ring of berberine chloride, while interacted with A ring and D ring of epiberberine. We further demonstrated the efficacy of epiberberine in the ruminal microbial fermentation with low ammonia release and urea degradation. In conclusion, our study clearly indicates that epiberberine is a promising candidate as a safe and effective inhibitor of rumen microbial urease and provides an optimal strategy and suitable feed additive for regulating nitrogen excretion in ruminants in the future. KEY POINTS: • Epiberberine is the most effective inhibitor of rumen urease from Rhizoma Coptidis. • Urease accessory protein UreG is an effective target for design of urease inhibitor. • Epiberberine may be used as natural feed additive to reducing NH3 release in ruminants.


Berberine , Berberine/analogs & derivatives , Animals , Berberine/pharmacology , Urease , Ammonia , Chlorides , Rumen , Enzyme Inhibitors/pharmacology , Nitrogen , Ruminants
19.
Chem Sci ; 15(15): 5775-5785, 2024 Apr 17.
Article En | MEDLINE | ID: mdl-38638235

Bacterial infections, as the second leading cause of global death, are commonly treated with antibiotics. However, the improper use of antibiotics contributes to the development of bacterial resistance. Therefore, the accurate differentiation between bacterial and non-bacterial inflammations is of utmost importance in the judicious administration of clinical antibiotics and the prevention of bacterial resistance. However, as of now, no fluorescent probes have yet been designed for the relevant assessments. To this end, the present study reports the development of a novel fluorescence probe (CyQ) that exhibits dual-enzyme responsiveness. The designed probe demonstrated excellent sensitivity in detecting NTR and NAD(P)H, which served as critical indicators for bacterial and non-bacterial inflammations. The utilization of CyQ enabled the efficient detection of NTR and NAD(P)H in distinct channels, exhibiting impressive detection limits of 0.26 µg mL-1 for NTR and 5.54 µM for NAD(P)H, respectively. Experimental trials conducted on living cells demonstrated CyQ's ability to differentiate the variations in NTR and NAD(P)H levels between A. baumannii, S. aureus, E. faecium, and P. aeruginosa-infected as well as LPS-stimulated HUVEC cells. Furthermore, in vivo zebrafish experiments demonstrated the efficacy of CyQ in accurately discerning variations in NTR and NAD(P)H levels resulting from bacterial infection or LPS stimulation, thereby facilitating non-invasive detection of both bacterial and non-bacterial inflammations. The outstanding discriminatory ability of CyQ between bacterial and non-bacterial inflammation positions it as a promising clinical diagnostic tool for acute inflammations.

20.
ACS Sens ; 9(5): 2421-2428, 2024 May 24.
Article En | MEDLINE | ID: mdl-38644577

A core-shell nanostructure of gold nanoparticles@covalent organic framework (COF) loaded with palladium nanoparticles (AuNPs@COF-PdNPs) was designed for the rapid monitoring of catalytic reactions with surface-enhanced Raman spectroscopy (SERS). The nanostructure was prepared by coating the COF layer on AuNPs and then in situ synthesizing PdNPs within the COF shell. With the respective SERS activity and catalytic performance of the AuNP core and COF-PdNPs shell, the nanostructure can be directly used in the SERS study of the catalytic reaction processes. It was shown that the confinement effect of COF resulted in the high dispersity of PdNPs and outstanding catalytic activity of AuNPs@COF-PdNPs, thus improving the reaction rate constant of the AuNPs@COF-PdNPs-catalyzed hydrogenation reduction by 10 times higher than that obtained with Au/Pd NPs. In addition, the COF layer can serve as a protective shell to make AuNPs@COF-PdNPs possess excellent reusability. Moreover, the loading of PdNPs within the COF layer was found to be in favor of avoiding intermediate products to achieve a high total conversion rate. AuNPs@COF-PdNPs also showed great catalytic activities toward the Suzuki-Miyaura coupling reaction. Taken together, the proposed core-shell nanostructure has great potential in monitoring and exploring catalytic processes and interfacial reactions.


Gold , Metal Nanoparticles , Palladium , Spectrum Analysis, Raman , Gold/chemistry , Spectrum Analysis, Raman/methods , Palladium/chemistry , Metal Nanoparticles/chemistry , Catalysis , Metal-Organic Frameworks/chemistry , Surface Properties , Hydrogenation
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