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1.
ACS Sens ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700898

RESUMO

Early diagnosis of drug-induced kidney injury (DIKI) is essential for clinical treatment and intervention. However, developing a reliable method to trace kidney injury origins through retrospective studies remains a challenge. In this study, we designed ordered fried-bun-shaped Au nanocone arrays (FBS NCAs) to create microarray chips as a surface-enhanced Raman scattering (SERS) analysis platform. Subsequently, the principal component analysis (PCA)-two-layer nearest neighbor (TLNN) model was constructed to identify and analyze the SERS spectra of exosomes from renal injury induced by cisplatin and gentamycin. The established PCA-TLNN model successfully differentiated the SERS spectra of exosomes from renal injury at different stages and causes, capturing the most significant spectral features for distinguishing these variations. For the SERS spectra of exosomes from renal injury at different induction times, the accuracy of PCA-TLNN reached 97.8% (cisplatin) and 93.3% (gentamicin). For the SERS spectra of exosomes from renal injury caused by different agents, the accuracy of PCA-TLNN reached 100% (7 days) and 96.7% (14 days). This study demonstrates that the combination of label-free exosome SERS and machine learning could serve as an innovative strategy for medical diagnosis and therapeutic intervention.

2.
FASEB J ; 38(7): e23599, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38572590

RESUMO

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease globally. Currently, there are no effective drugs for the treatment of DN. Although several studies have reported the therapeutic potential of mesenchymal stem cells, the underlying mechanisms remain largely unknown. Here, we report that both human umbilical cord MSCs (UC-MSCs) and UC-MSC-derived exosomes (UC-MSC-exo) attenuate kidney damage, and inhibit epithelial-mesenchymal transition (EMT) and renal fibrosis in streptozotocin-induced DN rats. Strikingly, the Hedgehog receptor, smoothened (SMO), was significantly upregulated in the kidney tissues of DN patients and rats, and positively correlated with EMT and renal fibrosis. UC-MSC and UC-MSC-exo treatment resulted in decrease of SMO expression. In vitro co-culture experiments revealed that UC-MSC-exo reduced EMT of tubular epithelial cells through inhibiting Hedgehog/SMO pathway. Collectively, UC-MSCs inhibit EMT and renal fibrosis by delivering exosomes and targeting Hedgehog/SMO signaling, suggesting that UC-MSCs and their exosomes are novel anti-fibrotic therapeutics for treating DN.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Exossomos , Células-Tronco Mesenquimais , Humanos , Ratos , Animais , Nefropatias Diabéticas/metabolismo , Exossomos/metabolismo , Receptor Smoothened , Proteínas Hedgehog/metabolismo , Fibrose , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical/metabolismo , Diabetes Mellitus/metabolismo
3.
Phys Chem Chem Phys ; 26(7): 6292-6299, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38305764

RESUMO

Two-dimensional material-supported single metal atom catalysts have been extensively studied and proved effective in electrocatalytic reactions in recent years. In this work, we systematically investigate the OER catalytic properties of single metal atoms supported by the NiN2 monolayer. Several typical transition metals with high single atom catalytic activity, such as Fe, Co, Ru, Rh, Pd, Ir, and Pt, were selected as catalytic active sites. The energy calculations show that transition metal atoms (Fe, Co, Ru, Rh, Pd, Ir, and Pt) are easily embedded in the NiN2 monolayer with Ni vacancies due to the negative binding energy. The calculated OER overpotentials of Fe, Co, Ru, Rh, Pd, Ir and Pt embedded NiN2 monolayers are 0.92 V, 0.47 V, 1.13 V, 0.66 V, 1.25 V, 0.28 V, and 0.94 V, respectively. Compared to the 0.57 V OER overpotential of typical OER noble metal catalysts IrO2, Co@NiN2 and Ir@NiN2 exhibit high OER catalytic activity due to lower overpotential, especially for Ir@NiN2. The high catalytic activity of the Ir embedded NiN2 monolayer can be explained well by the d-band center model. It is found that the adsorption strength of the embedded TM atoms with intermediates follows a linear relationship with their d-band centers. Besides, the overpotential of the Ir embedded NiN2 monolayer can be further reduced to 0.24 V under -2% biaxial strain. Such findings are expected to be employed in more two-dimensional material-supported single metal atom catalyzed reactions.

4.
J Am Chem Soc ; 146(10): 6806-6816, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38422481

RESUMO

The photochemical deprotection of structurally engineered o-nitrobenzylphosphate-caged hairpin nucleic acids is introduced as a versatile method to evolve constitutional dynamic networks, CDNs. The photogenerated CDNs, in the presence of fuel strands, interact with auxiliary CDNs, resulting in their dynamically equilibrated reconfiguration. By modification of the constituents associated with the auxiliary CDNs with glucose oxidase (GOx)/horseradish peroxidase (HRP) or the lactate dehydrogenase (LDH)/nicotinamide adenine dinucleotide (NAD+) cofactor, the photogenerated CDN drives the orthogonal operation upregulated/downregulated operation of the GOx/HRP and LDH/NAD+ biocatalytic cascade in the conjugate mixture of auxiliary CDNs. Also, the photogenerated CDN was applied to control the reconfiguration of coupled CDNs, leading to upregulated/downregulated formation of the antithrombin aptamer units, resulting in the dictated inhibition of thrombin activity (fibrinogen coagulation). Moreover, a reaction module consisting of GOx/HRP-modified o-nitrobenzyl phosphate-caged DNA hairpins, photoresponsive caged auxiliary duplexes, and nickase leads upon irradiation to the emergence of a transient, dissipative CDN activating in the presence of two alternate auxiliary triggers, achieving transient operation of up- and downregulated GOx/HRP biocatalytic cascades.


Assuntos
DNA Catalítico , DNA Catalítico/metabolismo , NAD , DNA/genética , Biocatálise , Oligonucleotídeos
5.
Bioact Mater ; 34: 17-36, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38173843

RESUMO

Abdominal Aortic Aneurysm (AAA) is a life-threatening vascular disease characterized by the weakening and ballooning of the abdominal aorta, which has no effective therapeutic approaches due to unclear molecular mechanisms. Using single-cell RNA sequencing, we analyzed the molecular profile of individual cells within control and AAA abdominal aortas. We found cellular heterogeneity, with increased plasmacytoid dendritic cells and reduced endothelial cells and vascular smooth muscle cells (VSMCs) in AAA. Up-regulated genes in AAA were associated with muscle tissue development and apoptosis. Genes controlling VSMCs aberrant switch from contractile to synthetic phenotype were significantly enriched in AAA. Additionally, VSMCs in AAA exhibited cell senescence and impaired oxidative phosphorylation. Similar observations were made in a mouse model of AAA induced by Angiotensin II, further affirming the relevance of our findings to human AAA. The concurrence of gene expression changes between human and mouse highlighted the impairment of oxidative phosphorylation as a potential target for intervention. Nicotinamide phosphoribosyltransferase (NAMPT, also named VISFATIN) signaling emerged as a signature event in AAA. NAMPT was significantly downregulated in AAA. NAMPT-extracellular vesicles (EVs) derived from mesenchymal stem cells restored NAMPT levels, and offered protection against AAA. Furthermore, NAMPT-EVs not only repressed injuries, such as cell senescence and DNA damage, but also rescued impairments of oxidative phosphorylation in both mouse and human AAA models, suggesting NAMPT supplementation as a potential therapeutic approach for AAA treatment. These findings shed light on the cellular heterogeneity and injuries in AAA, and offered promising therapeutic intervention for AAA treatment.

6.
Adv Mater ; 36(10): e2210885, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37083210

RESUMO

Conjugation of aptamers to homogeneous catalysts ("nucleoapzymes"), heterogeneous nanoparticle catalysts ("aptananozymes"), and photocatalysts ("photoaptazymes") yields superior catalytic/photocatalytic hybrid nanostructures emulating functions of native enzymes and photosystems. The concentration of the substrate in proximity to the catalytic sites ("molarity effect") or spatial concentration of electron-acceptor units in spatial proximity to the photosensitizers, by aptamer-ligand complexes, leads to enhanced catalytic/photocatalytic efficacies of the hybrid nanostructures. This is exemplified by sets of "nucleoapzymes" composed of aptamers conjugated to the hemin/G-quadruplex DNAzymes or metal-ligand complexes as catalysts, catalyzing the oxidation of dopamine to aminochrome, oxygen-insertion into the Ar─H moiety of tyrosinamide and the subsequent oxidation of the catechol product into aminochrome, or the hydrolysis of esters or ATP. Also, aptananozymes consisting of aptamers conjugated to Cu2+ - or Ce4+ -ion-modified C-dots or polyadenine-stabilized Au nanoparticles acting as catalysts oxidizing dopamine or operating bioreactor biocatalytic cascades, are demonstrated. In addition, aptamers conjugated to the Ru(II)-tris-bipyridine photosensitizer or the Zn(II) protoporphyrin IX photosensitizer provide supramolecular photoaptazyme assemblies emulating native photosynthetic reaction centers. Effective photoinduced electron transfer followed by the catalyzed synthesis of NADPH or the evolution of H2 is demonstrated by the photosystems. Structure-function relationships dictate the catalytic and photocatalytic efficacies of the systems.


Assuntos
Indolquinonas , Nanopartículas Metálicas , Fármacos Fotossensibilizantes , Dopamina , Ligantes , Ouro , Oligonucleotídeos , Catálise
7.
World J Emerg Med ; 14(5): 372-379, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37908798

RESUMO

BACKGROUND: It is controversial whether prophylactic endotracheal intubation (PEI) protects the airway before endoscopy in critically ill patients with upper gastrointestinal bleeding (UGIB). The study aimed to explore the predictive value of PEI for cardiopulmonary outcomes and identify high-risk patients with UGIB undergoing endoscopy. METHODS: Patients undergoing endoscopy for UGIB were retrospectively enrolled in the eICU Collaborative Research Database (eICU-CRD). The composite cardiopulmonary outcomes included aspiration, pneumonia, pulmonary edema, shock or hypotension, cardiac arrest, myocardial infarction, and arrhythmia. The incidence of cardiopulmonary outcomes within 48 h after endoscopy was compared between the PEI and non-PEI groups. Logistic regression analyses and propensity score matching analyses were performed to estimate effects of PEI on cardiopulmonary outcomes. Moreover, restricted cubic spline plots were used to assess for any threshold effects in the association between baseline variables and risk of cardiopulmonary outcomes (yes/no) in the PEI group. RESULTS: A total of 946 patients were divided into the PEI group (108/946, 11.4%) and the non-PEI group (838/946, 88.6%). After propensity score matching, the PEI group (n=50) had a higher incidence of cardiopulmonary outcomes (58.0% vs. 30.3%, P=0.001). PEI was a risk factor for cardiopulmonary outcomes after adjusting for confounders (odds ratio [OR] 3.176, 95% confidence interval [95% CI] 1.567-6.438, P=0.001). The subgroup analysis indicated the similar results. A shock index >0.77 was a predictor for cardiopulmonary outcomes in patients undergoing PEI (P=0.015). The probability of cardiopulmonary outcomes in the PEI group depended on the Charlson Comorbidity Index (OR 1.465, 95% CI 1.079-1.989, P=0.014) and shock index >0.77 (compared with shock index ≤0.77 [OR 2.981, 95% CI 1.186-7.492, P=0.020, AUC=0.764]). CONCLUSION: PEI may be associated with cardiopulmonary outcomes in elderly and critically ill patients with UGIB undergoing endoscopy. Furthermore, a shock index greater than 0.77 could be used as a predictor of a worse prognosis in patients undergoing PEI.

9.
J Environ Manage ; 347: 119090, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37793289

RESUMO

Hydrochar from agricultural wastes is regarded as a prospective and low-cost material to activate peroxymonosulfate (PMS) for degrading pollutants. Herein, a novel in-situ N-doped hydrochar composite (RHCM4) was synthesized using montmorillonite and waste reed straw rich in nitrogen as pyrolysis catalyst and carbon source, respectively. The fabricated RHCM4 possessed excellent PMS activation performance for decomposing quinclorac (QC), a refractory herbicide, with a high removal efficiency of 100.0% and mineralization efficiency of 75.1%. The quenching experiments and electron spin resonance (ESR) detection disclosed free radicals (•OH, •SO4-, and •O2-) and non-radicals (1O2) took part in the QC degradation process. Additionally, the catalytic mechanisms were analyzed in depth with the aid of various characterizations. Moreover, the QC degradation intermediates and pathways were clarified by density functional theory calculations and HPLC-MS. Importantly, phytotoxicity experiments showed that RHCM4/PMS could efficaciously mitigate the injury of QC to Solanaceae crops (pepper, tomato, and tobacco). These findings give a new idea for enhancing the catalytic activity of hydrochar from agricultural wastes and broaden its application in the field of agricultural environment.


Assuntos
Solanaceae , Estudos Prospectivos , Peróxidos , Verduras
10.
Medicine (Baltimore) ; 102(38): e34915, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37747002

RESUMO

The aim of this study was to investigate the association between serum uric acid (UA) levels and hypertension in American individuals 20 years of age and older. We used continuous cross-sectional surveys from the National Health and Nutrition Examination Survey in the United States from 2007 to 2016. Our selected population was adults aged 20 years and older in the United States. We examined the association between serum UA and risk of hypertension using weighted univariate logistic regression analysis, weighted multivariate logistic regression analysis, weighted subgroup analysis, and weighted restricted cubic spline analysis. Serum UA was significantly linked with hypertension in a multivariate logistic regression model adjusted for all variables (odds ratio [OR]: 1.22, 95% confidence interval [CI]: 1.15-1.28, P < .001). Furthermore, dividing serum UA into quartiles (Q) revealed an association between elevated serum UA and increased risk of hypertension [Q1 = (OR: 1.00), Q2 = (OR: 1.13, 95% CI: 0.95-1.37, P = .159), Q3 = OR: 1.30, 95% CI: 1.10-1.52, P = .002), Q4 = OR: 1.94, 95% CI: 1.58-2.38, P = .161). Additionally, we conducted subgroup analyses for age, sex, race, education, marital status, diabetes status, smoking, and alcohol use and discovered that these factors had a moderating effect on serum UA and hypertension (P < .05). Last but not least, we looked into the nonlinear link between serum UA and hypertension using weighted restricted cubic splines and discovered that there was no such relationship. The segmental effect of serum UA and hypertension, with an inflection point of 5.079 (mg/dL), was discovered in our gender-stratified study. And in analyses stratified by race and marital status, we similarly found a dose-response relationship between UA and hypertension among Hispanics and unmarried people. Our study showed a positive correlation between serum UA and hypertension.


Assuntos
Hipertensão , Ácido Úrico , Adulto , Humanos , Adulto Jovem , Estudos Transversais , Inquéritos Nutricionais , Hipertensão/epidemiologia , Consumo de Bebidas Alcoólicas
11.
Front Immunol ; 14: 1235982, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37767099

RESUMO

Purpose: Several existing studies have revealed that the occurrence of lichen planus (LP) is relevant to the gut microbiota, and the causal relationship between gut microbiota and LP was analyzed using the Mendelian randomization (MR) method. Methods: Through the two-sample MR method, single nucleotide polymorphisms (SNPs) relevant to gut microbiota were selected as instrument variables (IVs) to evaluate the causal association between gut microbiota and the risk of LP. Results: According to the selection criteria of inverse-variance weighted (IVW), six bacterial genera were found to be significantly linked to the initiation of LP; The IVW results suggested that Oxalobacteraceae, Victivallaceae, and Actinobacteria could restrain the initiation of LP, showing protective effects against LP. Desulfovibrio, Veillonella, and Ruminococcus gauvreauii groups were demonstrated to have casual correlations with the onset of LP. Conclusion: The relationship between gut microbiota and LP was not a single positive or inverse relationship. Investigation of the causal relationship of these gut microbiota with LP could further provide evidence for the intestine-skin axis theory. However, the specific mechanism of microorganisms affecting the skin remains to be clarified. In this paper, the protective effects and mechanisms of Oxalobacteraceae, Victivallaceae, and Actinobacteria on LP require further exploration.

12.
J Am Chem Soc ; 145(40): 22135-22149, 2023 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-37773962

RESUMO

DNA frameworks, consisting of constitutional dynamic networks (CDNs) undergoing fuel-driven reconfiguration, are coupled to a dissipative reaction module that triggers the reconfigured CDNs into a transient intermediate CDNs recovering the parent CDN state. Biocatalytic cascades consisting of the glucose oxidase (GOx)/horseradish peroxidase (HRP) couple or the lactate dehydrogenase (LDH)/nicotinamide adenine dinucleotide (NAD+) couple are tethered to the constituents of two different CDNs, allowing the CDNs-guided operation of the spatially confined GOx/HRP or LDH/NAD+ biocatalytic cascades. By applying two different fuel triggers, the directional transient CDN-guided upregulation/downregulation of the two biocatalytic cascades are demonstrated. By mixing the GOx/HRP-biocatalyst-modified CDN with the LDH/NAD+-biocatalyst-functionalized CDN, a composite CDN is assembled. Triggering the composite CDN with two different fuel strands results in orthogonal transient upregulation of the GOx/HRP cascade and transient downregulation of the LDH/NAD+ cascade or vice versa. The transient CDNs-guided biocatalytic cascades are computationally simulated by kinetic models, and the computational analyses allow the prediction of the performance of transient biocatalytic cascades under different auxiliary conditions. The concept of orthogonally triggered temporal, transient, biocatalytic cascades by means of CDN frameworks is applied to design an orthogonally operating CDN for the temporal upregulated or downregulated transient thrombin-induced coagulation of fibrinogen to fibrin.


Assuntos
DNA Catalítico , DNA Catalítico/metabolismo , NAD , DNA , Biocatálise , Glucose Oxidase/metabolismo
13.
Anal Chem ; 95(39): 14558-14565, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37734161

RESUMO

In this work, the orderly aggregated catalytic hairpin assembly (OA-CHA) was developed for synchronous ultrasensitive detection and high-efficiency colocalization imaging of dual-miRNAs by a carefully designed tetrahedral conjugated ladder DNA structure (TCLDS). Exactly, two diverse hairpin probes were fixed on tetrahedron conjugated DNA nanowires to form the TCLDS without fluorescence response, which triggered OA-CHA in the aid of output DNA 1 and output DNA 2 produced by targets miRNA-217 and miRNA-196a cycle to generate TCLDS with remarkable fluorescence response. Impressively, compared with the traditional CHA strategy, OA-CHA avoided the fluorescence group and quenching group from approaching again because of the spatial confinement effect to significantly enhance the fluorescence signal, resulting in the simultaneous ultrasensitive detection of dual-miRNAs with detection limits of 21 and 32 fM for miRNA-217 and miRNA-196a, respectively. Meanwhile, the TCLDS with lower diffusivity could achieve accurate localization imaging for reflecting the spatial distribution of dual-miRNAs in living cells. The strategy based on OA-CHA provided a flexible and programmable nucleic amplification method for the synchronous ultrasensitive detection and precise imaging of multiple biomarkers and had potential in disease diagnostics..


Assuntos
Técnicas Biossensoriais , DNA Catalítico , MicroRNAs , MicroRNAs/genética , Técnicas Biossensoriais/métodos , DNA/química , Diagnóstico por Imagem , Catálise , Limite de Detecção
14.
Nano Lett ; 23(18): 8664-8673, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37669541

RESUMO

Glucose oxidase-loaded ZIF-90 metal-organic framework nanoparticles conjugated to hemin-G-quadruplexes act as functional bioreactor hybrids operating transient dissipative biocatalytic cascaded transformations consisting of the glucose-driven H2O2-mediated oxidation of Amplex-Red to resorufin or the glucose-driven generation of chemiluminescence by the H2O2-mediated oxidation of luminol. One system involves the fueled activation of a reaction module leading to the temporal formation and depletion of the bioreactor conjugate operating the nickase-guided transient biocatalytic cascades. The second system demonstrates the fueled activation of a reaction module yielding a bioreactor conjugate operating the exonuclease III-dictated transient operation of the two biocatalytic cascades. The temporal operations of the bioreactor circuits are accompanied by kinetic models and computational simulations enabling us to predict the dynamic behavior of the systems subjected to different auxiliary conditions.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Quadruplex G , Estruturas Metalorgânicas , Nanopartículas , Glucose Oxidase/metabolismo , Peróxido de Hidrogênio , Glucose , Reatores Biológicos , Hemina
15.
Angew Chem Int Ed Engl ; 62(43): e202311590, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37675854

RESUMO

The combination of gene therapy and immunotherapy concepts, along recent advances in DNA nanotechnology, have the potential to provide important tools for cancer therapies. We present the development of stimuli-responsive microcapsules, loaded with a viral immunogenetic agent, harnessing the immune response against the Coronavirus Disease 2019, COVID-19, to selectively attack liver cancer cells (hepatoma) or recognize breast cancer or hepatoma, by expression of green fluorescence protein, GFP. The pH-responsive microcapsules, modified with DNA-tetrahedra nanostructures, increased hepatoma permeation by 50 %. Incorporation of a GFP-encoding lentivirus vector inside the tumor-targeting pH-stimulated miRNA-triggered and Alpha-fetoprotein-dictated microcapsules enables the demonstration of neoplasm selectivity, with approximately 5,000-, 8,000- and 50,000-fold more expression in the cancerous cells, respectively. The incorporation of the SARS-CoV-2 spike protein in the gene vector promotes specific recognition of the immune-evading hepatoma by the COVID-19-analogous immune response, which leads to cytotoxic and inflammatory activity, mediated by serum components taken from vaccinated or recovered COVID-19 patients, resulting in effective elimination of the hepatoma (>85 % yield).

16.
J Chem Phys ; 159(6)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37565684

RESUMO

The propensity of water to remain in a metastable liquid state at temperatures below its equilibrium melting point holds significant potential for cryopreserving biological material such as tissues and organs. The benefits conferred are a direct result of progressively reducing metabolic expenditure due to colder temperatures while simultaneously avoiding the irreversible damage caused by the crystallization of ice. Unfortunately, the freezing of water in bulk systems of clinical relevance is dominated by random heterogeneous nucleation initiated by uncharacterized trace impurities, and the marked unpredictability of this behavior has prevented the implementation of supercooling outside of controlled laboratory settings and in volumes larger than a few milliliters. Here, we develop a statistical model that jointly captures both the inherent stochastic nature of nucleation using conventional Poisson statistics as well as the random variability of heterogeneous nucleation catalysis through bivariate extreme value statistics. Individually, these two classes of models cannot account for both the time-dependent nature of nucleation and the sample-to-sample variability associated with heterogeneous catalysis, and traditional extreme value models have only considered variations of the characteristic nucleation temperature. We conduct a series of constant cooling rate and isothermal nucleation experiments with physiological saline solutions and leverage the statistical model to evaluate the natural variability of kinetic and thermodynamic nucleation parameters. By quantifying freezing probability as a function of temperature, supercooled duration, and system volume while accounting for nucleation site variability, this study also provides a basis for the rational design of stable supercooled biopreservation protocols.

17.
ACS Omega ; 8(32): 29836-29846, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37599935

RESUMO

Surface-enhanced Raman scattering (SERS) is a widely used rapid and noninvasive method for detecting biological substances in serum samples and is commonly employed in disease screening and diagnosis. Solid-state nanoarray SERS substrates used in serum detection may cause spectral instability due to imperfections in the detection method. For the purpose of identifying optimal detection conditions, various dilution levels of the serum were tested in this study. The study found that a complete and stable serum SERS spectrum can be obtained when the serum is diluted by a factor of 50. The study reports the successful preparation of an Au nanocone array (Au NCA) plasmonic substrate with a uniform, controllable microstructure and high activity, achieved through a combination of PS colloidal sphere template-assisted reactive ion etching (RIE) process and magnetron sputtering deposition technology. Based on this substrate, a standard detection scheme was developed to obtain highly stable and repeatable serum SERS spectra. The study verified the reliability of the optimized serum detection scheme by comparing the SERS spectra of serum samples from healthy individuals and gastric cancer patients, and confirmed the potential benefits of the scheme for disease screening and diagnosis.

18.
Anal Chem ; 95(34): 12754-12760, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37590171

RESUMO

In this study, a pH-stimulated self-locked DNA nanostructure (SLDN) was developed to efficiently distinguish cancer cells from other cells for the simultaneous detection and imaging of endogenous dual-microRNAs (miRNAs). Impressively, the SLDN was specifically unlocked in the acidic environment of cancer cells to form unlocked-SLDN to disengage the i-motif sequence with a labeled fluorophore for the recovery of a fluorescence signal, resulting in the differentiation of cancer cells from normal cells. Meanwhile, unlocked-SLDN could combine and recognize the targets miRNA-21 and miRNA-155 simultaneously to trigger the hybridization chain reaction (HCR) amplification for sensitive dual-miRNA detection, with detection limits of 1.46 pM for miRNA-21 and 0.72 pM for miRNA-155. Significantly, compared with the current miRNA imaging strategy based on the traditional DNA nanostructure, the strategy proposed here remarkably eliminates the interference of normal cells to achieve high-resolution colocation imaging of miRNAs in tumor cells with an ultralow background signal. This work provided a specific differentiation method for tumor cells to materialize sensitive biomarker detection and distinguishable high-definition live-cell imaging for precise cancer diagnosis and multifactor research of tumor progression.


Assuntos
MicroRNAs , Nanoestruturas , Neoplasias , Sequências Repetitivas de Ácido Nucleico , Diferenciação Celular , Concentração de Íons de Hidrogênio , Neoplasias/diagnóstico por imagem
19.
Food Funct ; 14(17): 7992-8007, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37580964

RESUMO

Procyanidin-amino acid interactions during transmembrane transport cause changes in the structural and physical properties of peptides, which limits further absorption of oligopeptide-advanced glycation end products (AGEs). In this study, glycated casein hydrolysates (GCSHs) were employed to investigate the structure and interaction mechanism of GCSH with lotus seedpod oligomeric procyanidin (LSOPC) complexes in an intestinal environment. LSOPC can interact with GCSH under certain conditions to form hydrogen bonds and hydrophobic interactions to form GCSH-LSOPC complexes. Results showed that procyanidin further leads to the transformation of a GCSH secondary structure and the increase of surface hydrophobicity (H0). The strongest non-covalent interaction between GCSH and (-)-epigallocatechin gallate (EGCG) was due to the polyhydroxy structure of EGCG. Binding site analysis showed that EGCG binds to the internal cavity of P1 to maintain the relative stability of the binding conformation. The antioxidant capacity of GCSH was remarkably elevated by GCSH-LSOPC. This study will provide a new reference for the accurate control of oligopeptide-AGEs absorption by LSOPC in vivo.


Assuntos
Catequina , Lotus , Proantocianidinas , Caseínas/análise , Extratos Vegetais/química , Proantocianidinas/química , Lotus/química , Antioxidantes/análise , Catequina/química , Produtos Finais de Glicação Avançada/metabolismo , Sementes/química , Digestão
20.
Artigo em Inglês | MEDLINE | ID: mdl-37578922

RESUMO

Graph Convolutional Network (GCN) excels at EEG recognition by capturing brain connections, but previous studies neglect the important EEG feature itself. In this study, we propose MSFR-GCN, a multi-scale feature reconstruction GCN for recognizing emotion and cognition tasks. Specifically, MSFR-GCN includes the MSFR and feature-pool characteristically, with the MSFR consisting of two sub-modules, multi-scale Squeeze-and-Excitation (MSSE) and multi-scale sample re-weighting (MSSR). MSSE assigns weights to channels and frequency bands based on their separate statistical information, while MSSR assigns sample weights based on combined channel and frequency information. The feature-pool, which pools across the feature dimension, is applied after GCN to retain EEG channel information. The MSFR-GCN achieves excellent results in emotion recognition when first tested on two public datasets, SEED and SEED-IV. Than the MSFR-GCN is tested on our self-collected Emotion and Cognition EEG dataset (ECED) for both emotion and cognition classification tasks. The results show MSFR-GCN's good performance in emotion and cognition classification tasks and reveal the implicit relationship between the two, which may provide aid in the rehabilitation of people with cognitive impairments from an emotional perspective.


Assuntos
Encéfalo , Cognição , Humanos , Emoções , Reconhecimento Psicológico , Eletroencefalografia
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