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1.
Anal Chem ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946419

RESUMO

Apurinic/apyrimidinic endonuclease 1 (APE1), as a vital base excision repair enzyme, is essential for maintaining genomic integrity and stability, and its abnormal expression is closely associated with malignant tumors. Herein, we constructed an electrochemiluminescence (ECL) biosensor for detecting APE1 activity by combining nanoconfined ECL silver nanoclusters (Ag NCs) with X-shaped DNA recognizer-triggered cascade amplification. Specifically, the Ag NCs were prepared and confined in the glutaraldehyde-cross-linked chitosan hydrogel network using the one-pot method, resulting in a strong ECL response and exceptional stability in comparison with discrete Ag NCs. Furthermore, the self-assembled X-shaped DNA recognizers were designed for APE1 detection, which not only improved reaction kinetics due to the ordered arrangement of recognition sites but also achieved high sensitivity by utilizing the recognizer-triggered cascade amplification of strand displacement amplification (SDA) and DNAzyme catalysis. As expected, this biosensor achieved sensitive ECL detection of APE1 in the range of 1.0 × 10-3 U·µL-1 to 1.0 × 10-10 U·µL-1 with the detection limit of 2.21 × 10-11 U·µL-1, rendering it a desirable approach for biomarker detection.

2.
Anal Chem ; 96(24): 9961-9968, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38838250

RESUMO

In this study, a novel europium dual-ligand metal-organic gel (Eu-D-MOGs) with high-efficient anodic annihilation electrochemiluminescence (ECL) was synthesized as an ECL emitter to construct a biosensor for ultrasensitive detection of microRNA-221 (miR-221). Impressively, compared to the ECL signal of europium single-ligand metal-organic gels (Eu-S-MOGs), the ECL signal of Eu-D-MOGs was significantly improved since the two organic ligands could jointly replace the H2O and coordinate with Eu3+, which could remarkably reduce the nonradiative vibrational energy transfer caused by the coordination between H2O and Eu3+ with a high coordination demand. In addition, Eu-D-MOGs could be electrochemically oxidized to Eu-D-MOGs•+ at 1.45 V and reduced to Eu-D-MOGs•- at 0.65 V to achieve effective annihilation of ECL, which overcame the side reaction brought by the remaining emitters at negative potential. This benefited from the annihilation ECL performance of the central ion Eu3+ caused by its redox in the electrochemical process. Furthermore, the annihilation ECL signal of Eu3+ could be improved by sensitizing Eu3+ via the antenna effect. In addition, combined with the improved rolling circle amplification-assisted strand displacement amplification strategy (RCA-SDA), a sensitive biosensor was constructed for the sensitive detection of miR-221 with a low detection limit of 5.12 aM and could be successfully applied for the detection of miR-221 in the lysate of cancer cells. This strategy offered a unique approach to synthesizing metal-organic gels as ECL emitters without a coreactant for the construction of ECL biosensing platforms in biomarker detection and disease diagnosis.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Európio , Géis , Medições Luminescentes , MicroRNAs , Európio/química , MicroRNAs/análise , Técnicas Eletroquímicas/métodos , Ligantes , Géis/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Humanos
3.
Cereb Cortex ; 34(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38771245

RESUMO

Arterial spin-labeled perfusion and blood oxygenation level-dependent functional MRI are indispensable tools for noninvasive human brain imaging in clinical and cognitive neuroscience, yet concerns persist regarding the reliability and reproducibility of functional MRI findings. The circadian rhythm is known to play a significant role in physiological and psychological responses, leading to variability in brain function at different times of the day. Despite this, test-retest reliability of brain function across different times of the day remains poorly understood. This study examined the test-retest reliability of six repeated cerebral blood flow measurements using arterial spin-labeled perfusion imaging both at resting-state and during the psychomotor vigilance test, as well as task-induced cerebral blood flow changes in a cohort of 38 healthy participants over a full day. The results demonstrated excellent test-retest reliability for absolute cerebral blood flow measurements at rest and during the psychomotor vigilance test throughout the day. However, task-induced cerebral blood flow changes exhibited poor reliability across various brain regions and networks. Furthermore, reliability declined over longer time intervals within the day, particularly during nighttime scans compared to daytime scans. These findings highlight the superior reliability of absolute cerebral blood flow compared to task-induced cerebral blood flow changes and emphasize the importance of controlling time-of-day effects to enhance the reliability and reproducibility of future brain imaging studies.


Assuntos
Encéfalo , Circulação Cerebrovascular , Imageamento por Ressonância Magnética , Descanso , Humanos , Masculino , Feminino , Adulto , Circulação Cerebrovascular/fisiologia , Reprodutibilidade dos Testes , Descanso/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Encéfalo/irrigação sanguínea , Adulto Jovem , Imageamento por Ressonância Magnética/métodos , Imagem de Perfusão/métodos , Desempenho Psicomotor/fisiologia , Ritmo Circadiano/fisiologia , Nível de Alerta/fisiologia
4.
Anal Chem ; 96(19): 7516-7523, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38691765

RESUMO

Herein, single-atom iron doped carbon dots (SA Fe-CDs) were successfully prepared as novel electrochemiluminescence (ECL) emitters with high ECL efficiency, and a biosensor was constructed to ultrasensitively detect microRNA-222 (miRNA-222). Importantly, compared with the conventional without single-atom doped CDs with low ECL efficiency, SA Fe-CDs exhibited strong ECL efficiency, in which single-atom iron as an advanced coreactant accelerator could significantly enhance the generation of reactive oxygen species (ROS) from the coreactant S2O82- for improving the ECL efficiency. Moreover, a neoteric amplification strategy combining the improved strand displacement amplification with Nt.BbvCI enzyme-induced target amplification (ISDA-EITA) could produce 4 output DNAs in every cycle, which greatly improved the amplification efficiency. Thus, a useful ECL biosensor was built with a detection limit of 16.60 aM in the range of 100 aM to 1 nM for detecting traces of miRNA-222. In addition, miRNA-222 in cancer cell lysate (MHCC-97L) was successfully detected by using the ECL biosensor. Therefore, this strategy provides highly efficient single-atom doped ECL emitters for the construction of sensitive ECL biosensing platforms in the biological field and clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Carbono , Técnicas Eletroquímicas , Ferro , Medições Luminescentes , MicroRNAs , Pontos Quânticos , MicroRNAs/análise , Carbono/química , Ferro/química , Técnicas Eletroquímicas/métodos , Pontos Quânticos/química , Humanos , Técnicas Biossensoriais/métodos , Limite de Detecção
5.
Biosens Bioelectron ; 254: 116193, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38479342

RESUMO

Herein, a new electrochemiluminescence (ECL) biosensor was constructed with highly efficient polymerized carbon dots (PCDs) as ECL emitter and the improved localized catalytic hairpin assembly (L-CHA) as signal amplifier for ultrasensitive detection of microRNA-222 (miRNA-222). Impressively, compared to the traditional carbon dots with inefficient blue region ECL emission, PCDs with N, O co-dope and large conjugated π-system showed high electrical conductivity, narrow band gap and strong radiative transition, which could exhibit high ECL efficiency to improve the sensitivity of detection and long wavelength ECL emission to achieve deep tissue penetration for reducing biological damage. Furthermore, the trace target miRNA-222 could be efficiently converted into large amounts of output DNA labelled with the quencher dopamine (S-DA) through the L-CHA reaction to significantly enhance the target amplification efficiency for further improving the sensitivity of detection. Thus, the ECL biosensor could achieve the ultrasensitive detection of miRNA-222 from 100 aM to 100 pM with the detection limit of 76 aM. Therefore, this work proposed a novel CDs with high ECL efficiency and long wavelength ECL emission, which not only was used to build an ultrasensitive biosensor for biomolecules detection in clinical diagnosis, but also served as a potential emitter for ECL bioimaging.


Assuntos
Técnicas Biossensoriais , MicroRNAs , MicroRNAs/genética , Carbono , Medições Luminescentes/métodos , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção
6.
Anal Chem ; 96(11): 4589-4596, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38442212

RESUMO

Herein, novel europium metal-organic gels (Eu-MOGs) with excellent cathode electrochemiluminescence (ECL) emission are first used to construct biosensors for the ultrasensitive detection of miRNA-222. Impressively, N and O elements of organic ligand 2,2':6,2″-terpyridine 4,4',4″-tricarboxylic acid (H3-tctpy) can perfectly coordinate with Eu3+ to form Eu-MOGs, which not only reduce nonradiative transition caused by the intramolecular free rotation of phenyl rings in other MOGs to enhance the ECL signal with extraordinary ECL efficiency as high as 37.2% (vs the [Ru(bpy)3]2+/S2O82- ECL system) but also reinforce ligand-to-metal charge transfer (LMCT) by the strong affinity between Eu3+ and N and O elements to greatly improve the stability of ECL signals. Besides, an improved nucleic acid cascade amplification reaction is developed to greatly raise the conversion efficiency from target miRNA-222 to a DNAzyme-mediated dual-drive DNA walker as output DNA, which can simultaneously shear the specific recognition sites from two directions. In that way, the proposed biosensor can further enhance the detection sensitivity of miRNA-222 with a linear range of 10 aM-1 nM and a detection limit (LOD) of 8.5 aM, which can also achieve an accurate response in cancer cell lysates of MHCC-97L and HeLa. Additionally, the biosensor can be self-regenerated by the folding/unfolding of related triplets with pH changes to simplify experimental operations and reduce the cost. Hence, this work proposed novel MOGs with stable and intense ECL signals for the construction of a renewable ECL biosensor, supplying a reliable detection method in biomarker analysis and disease diagnosis.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , MicroRNAs , Humanos , Európio , Ligantes , DNA/química , Medições Luminescentes/métodos , MicroRNAs/análise , Técnicas Biossensoriais/métodos , Géis , Técnicas Eletroquímicas/métodos , Limite de Detecção
7.
Chem Sci ; 15(9): 3255-3261, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38425534

RESUMO

Here we report for the first time the phenomenon of continuously color-tunable electrochemiluminescence (ECL) from individual gold nanoclusters (Au NCs) confined in a porous hydrogel matrix by adjusting the concentration of the co-reactant. Specifically, the hydrogel-confined Au NCs exhibit strong dual-color ECL in an aqueous solution with triethylamine (TEA) as a co-reactant, with a record-breaking quantum yield of 95%. Unlike previously reported Au NCs, the ECL origin of the hydrogel-confined Au NCs is related to both the Au(0) kernel and the Au(i)-S surface. Surprisingly, the surface-related ECL of Au NCs exhibits a wide color-tunable range of 625-829 nm, but the core-related ECL remains constant at 489 nm. Theoretical and experimental studies demonstrate that the color-tunable ECL is caused by the dynamic surface reconstruction of Au NCs and TEA radicals. This work opens up new avenues for dynamically manipulating the ECL spectra of core-shell emitters in biosensing and imaging research.

8.
Anal Chem ; 96(9): 3837-3843, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38384162

RESUMO

Herein, an antibody-protein-aptamer electrochemical biosensor was designed by highly efficient proximity-induced DNA hybridization on a tetrahedral DNA nanostructure (TDN) for ultrasensitive detection of human insulin-like growth factor-1 (IGF-1). Impressively, the IGF-1 antibody immobilized on the top vertex of the TDN could effectively capture the target protein with less steric effect, and the ferrocene-labeled signal probe (SP) bound on the bottom vertex of the TDN was close to the electrode surface for generating a strong initial signal. In the presence of target protein IGF-1 and an aptamer strand, an antibody-protein-aptamer sandwich could be formed on the top vertex of TDN, which would trigger proximity-induced DNA hybridization to release the SP on the bottom vertex of TDN; therefore, the signal response would decrease dramatically, enhancing the sensitivity of the biosensor. As a result, the linear range of the proposed biosensor for target IGF-1 was 1 fM to 1 nM with the limit of detection down to 0.47 fM, which was much lower than that of the traditional TDN designs on electrochemical biosensors. Surprisingly, the use of this approach offered an innovative approach for the sensitive detection of biomarkers and illness diagnosis.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Humanos , Peptídeos Semelhantes à Insulina , Fator de Crescimento Insulin-Like I , DNA/química , Anticorpos , Oligonucleotídeos , Nanoestruturas/química , Técnicas Eletroquímicas , Limite de Detecção
9.
J Virol ; 98(1): e0166423, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38054618

RESUMO

Pseudorabies virus (PRV) is the causative agent of Aujeszky's disease in pigs. The low-density lipoprotein receptor (LDLR) is a transcriptional target of the sterol-regulatory element-binding proteins (SREBPs) and participates in the uptake of LDL-derived cholesterol. However, the involvement of LDLR in PRV infection has not been well characterized. We observed an increased expression level of LDLR mRNA in PRV-infected 3D4/21, PK-15, HeLa, RAW264.7, and L929 cells. The LDLR protein level was also upregulated by PRV infection in PK-15 cells and in murine lung and brain. The treatment of cells with the SREBP inhibitor, fatostatin, or with SREBP2-specific small interfering RNA prevented the PRV-induced upregulation of LDLR expression as well as viral protein expression and progeny virus production. This suggested that PRV activated SREBPs to induce LDLR expression. Furthermore, interference in LDLR expression affected PRV proliferation, while LDLR overexpression promoted it. This indicated that LDLR was involved in PRV infection. The study also demonstrated that LDLR participated in PRV invasions. The overexpression of LDLR or inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9), which binds to LDLR and targets it for lysosomal degradation, significantly enhanced PRV attachment and entry. Mechanistically, LDLR interacted with PRV on the plasma membrane, and pretreatment of cells with LDLR antibodies was able to neutralize viral entry. An in vivo study indicated that the treatment of mice with the PCSK9 inhibitor SBC-115076 promoted PRV proliferation. The data from the study indicate that PRV hijacks LDLR for viral entry through the activation of SREBPs.IMPORTANCEPseudorabies virus (PRV) is a herpesvirus that primarily manifests as fever, pruritus, and encephalomyelitis in various domestic and wild animals. Owing to its lifelong latent infection characteristics, PRV outbreaks have led to significant financial setbacks in the global pig industry. There is evidence that PRV variant strains can infect humans, thereby crossing the species barrier. Therefore, gaining deeper insights into PRV pathogenesis and developing updated strategies to contain its spread are critical. This study posits that the low-density lipoprotein receptor (LDLR) could be a co-receptor for PRV infection. Hence, strategies targeting LDLR may provide a promising avenue for the development of effective PRV vaccines and therapeutic interventions.


Assuntos
Herpesvirus Suídeo 1 , Lipoproteínas LDL , Pseudorraiva , Doenças dos Suínos , Animais , Humanos , Camundongos , Herpesvirus Suídeo 1/fisiologia , Lipoproteínas LDL/metabolismo , Pró-Proteína Convertase 9 , Pseudorraiva/virologia , Suínos , Doenças dos Suínos/virologia , Internalização do Vírus , Linhagem Celular
10.
Psychophysiology ; 61(4): e14465, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37905305

RESUMO

Sleep loss impacts a broad range of brain and cognitive functions. However, how sleep deprivation affects risky decision-making remains inconclusive. This study used functional MRI to examine the impact of one night of total sleep deprivation (TSD) on risky decision-making behavior and the underlying brain responses in healthy adults. In this study, we analyzed data from N = 56 participants in a strictly controlled 5-day and 4-night in-laboratory study using a modified Balloon Analogue Risk Task. Participants completed two scan sessions in counter-balanced order, including one scan during rested wakefulness (RW) and another scan after one night of TSD. Results showed no differences in participants' risk-taking propensity and risk-induced activation between RW and TSD. However, participants showed significantly reduced neural activity in the anterior cingulate cortex and bilateral insula for loss outcomes, and in bilateral putamen for win outcomes during TSD compared with RW. Moreover, risk-induced activation in the insula negatively correlated with participants' risk-taking propensity during RW, while no such correlations were observed after TSD. These findings suggest that sleep loss may impact risky decision-making by attenuating neural responses to decision outcomes and impairing brain-behavior associations.


Assuntos
Tomada de Decisões , Privação do Sono , Adulto , Humanos , Tomada de Decisões/fisiologia , Encéfalo , Cognição , Giro do Cíngulo , Imageamento por Ressonância Magnética , Assunção de Riscos
11.
Anal Chem ; 95(45): 16625-16630, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37908115

RESUMO

Herein, a novel photocathodic nanocomposite poly{4,8-bis[5-(2-ethylhexyl)-thiophen-2-yl] benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4-b]thiophene-4,6-diyl}/phthalocyanine zinc (PTB7-Th/ZnPc) with high photoelectric conversion efficiency under long-wavelength illumination was prepared to construct an ultrasensitive biosensor for the detection of microRNA-21 (miRNA-21), accompanied by a prominent anti-interference capability toward reductive substances. Impressively, the new heterojunction PTB7-Th/ZnPc nanocomposite could not only generate a strong cathodic photocurrent to improve the detection sensitivity under long-wavelength illumination (660 nm) but also effectively avoid the high damage of biological activity caused by short-wavelength light stimulation. Accordingly, by coupling with rolling circle amplification (RCA)-triggered DNA amplification to form functional biquencher nanospheres, a PEC biosensor was fabricated to realize the ultrasensitive analysis of miRNA-21 in the concentration range of 0.1 fM to 10 nM with a detection limit as low as 32 aM. This strategy provided a novel long-wavelength illumination-induced photocurrent enhancement photoactive material for a sensitive and low-damage anti-interference bioassay and early clinical disease diagnosis.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Nanocompostos , Iluminação , Técnicas Eletroquímicas , MicroRNAs/análise
12.
Nat Sci Sleep ; 15: 823-838, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37850195

RESUMO

Purpose: Many studies have investigated the cognitive, emotional, and other impairments caused by sleep restriction. However, few studies have explored the relationship between cognitive performance and changes in sleep structure and electroencephalography (EEG) during sleep. The present study aimed to examine whether changes in sleep structure and EEG can account for cognitive impairment caused by sleep restriction. Patients and Methods: Sixteen young adults spent five consecutive nights (adaptation 9h, baseline 8h, 1st restriction 6h, 2nd restriction 6h, and recovery 10h) in a sleep laboratory, with polysomnography recordings taken during sleep. Throughout waking periods in each condition, participants completed the psychomotor vigilance test (PVT), which measures vigilant attention, and the Go/No-Go task, which measures inhibition control. Results: The results showed that sleep restriction significantly decreased the proportion of N1 and N2 sleep, increased the proportion of N3 sleep, and reduced the time spent awake after sleep onset (WASO) and sleep onset latency. Poorer performance on the PVT and Go/No Go task was associated with longer WASO, a larger proportion of N3 sleep, and a smaller proportion of N2 sleep. Additionally, the power spectral density of delta waves significantly increased after sleep restriction, and this increase predicted a decrease in vigilance and inhibition control the next day. Conclusion: These findings suggest that sleep architecture and EEG signatures may partially explain cognitive impairment caused by sleep restriction.

13.
Anal Chem ; 95(34): 12768-12775, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37587155

RESUMO

Herein, a surface-enhanced Raman scattering (SERS) biosensor was constructed by gold nanobipyramid (Au NBP) hotspot aggregation-induced SERS (HAI-SERS) for the ultrasensitive detection of microRNA-221 (miRNA-221). Impressively, compared with single Au NBP, the multiple Au NBPs assembled by tetrahedral DNA nanostructures (TDNs) could increase hotspot aggregation to significantly enhance the SERS signal of Raman molecule methylene blue (MB). Meanwhile, in the aid of Exo-III assisted target cycle amplification and TDNs-induced catalytic hairpin assembly (CHA) amplification, the biosensor could achieve the sensitive detection of miRNA-221 with a linear range of 1 fM-10 nM, and the limit of detection (LOD) was 0.59 fM, which could be used for practical application in MHCC-97L and MCF-7 cell lysates. This work provided a method for hotspot aggregation to enhance SERS for the detection of biomarkers and disease diagnosis.


Assuntos
MicroRNAs , Análise Espectral Raman , Catálise , Ouro , Limite de Detecção
14.
Anal Chem ; 95(35): 13156-13162, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37606955

RESUMO

Herein, by introducing gold nanostars (AuNSs) as fuel core, a near-infrared-driven nanorocket (NIDNR) with pretty fast walking was exploited for ultrasensitive miRNA detection. Compared with traditional nanomaterials-comprised nanomachines (NMs), the NIDNR possesses much better kinetic and thermodynamic performance owing to the extra photothermal driving force from localized surface plasmon (LSP). Impressively, the whole reaction time of NIDNR down to 15 min was realized, which is almost more than 8 times beyond those of conventional DNA-based NMs. This way, the inherent obstacle of traditional NMs, including long reaction time and low efficiency, could be easily addressed. As a proof of concept, the NIDNR was successfully applied to develop an electrochemical biosensing platform for rapid and sensitive detection of miRNA with an LOD down to 2.95 aM and achieved the real-time assay of real biological samples from human hepatocellular carcinoma cells (MHCC97L) and HeLa, thus providing an innovative insight to design more versatile DNA nanomachines for ultimate application in biosensing platform construction and clinical sample detection.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho/métodos , MicroRNAs/química , Fatores de Tempo , Ouro , Nanopartículas Metálicas/química , Técnicas Biossensoriais , Técnicas Reprodutivas , Humanos , Linhagem Celular Tumoral
15.
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
16.
Anal Chim Acta ; 1274: 341447, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37455065

RESUMO

Herein, we developed a novel three-dimensional (3D) self-accelerated DNA walker (SADW) which progressively expedite walking rate by unlocking the more walking arm continuously in walker process to construct electrochemical biosensor for ultrasensitive detection of microRNA. Particularly, we skillfully introduced a target analogue sequence in the double-loop hairpin, which could be released in the walking process of SADW, then rapidly activating more silenced walking strands to achieve the continuous self-acceleration, resulting in the expedited reaction rate. Surprisingly, the average reaction rate of SADW was quite higher than that of traditional 3D self-circulating DNA walkers (DW) under pretty low target miRNA concentration, which is ascribed to the outstanding acceleration process of the SADW, readily conquering the major predicaments of DW in detecting target with traces concentration: slow reaction rate and low sensitivity. This way, the elaborated SADW is favorably applied in the ultrasensitive and rapid detection of miRNA-21 in tumor cancer cell lysates with a detection limit down to 5.81 aM which was far from lower than the detection limit of DW. This approach develops the novel generation of widespread strategy for the applications in clinic diagnose, biosensing assay, and DNA nanobiotechnology.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Neoplasias , Humanos , MicroRNAs/genética , Limite de Detecção , Técnicas Eletroquímicas/métodos , DNA/genética , Técnicas Biossensoriais/métodos
17.
Proc Natl Acad Sci U S A ; 120(26): e2214505120, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37339227

RESUMO

Sleep loss robustly disrupts mood and emotion regulation in healthy individuals but can have a transient antidepressant effect in a subset of patients with depression. The neural mechanisms underlying this paradoxical effect remain unclear. Previous studies suggest that the amygdala and dorsal nexus (DN) play key roles in depressive mood regulation. Here, we used functional MRI to examine associations between amygdala- and DN-related resting-state connectivity alterations and mood changes after one night of total sleep deprivation (TSD) in both healthy adults and patients with major depressive disorder using strictly controlled in-laboratory studies. Behavioral data showed that TSD increased negative mood in healthy participants but reduced depressive symptoms in 43% of patients. Imaging data showed that TSD enhanced both amygdala- and DN-related connectivity in healthy participants. Moreover, enhanced amygdala connectivity to the anterior cingulate cortex (ACC) after TSD associated with better mood in healthy participants and antidepressant effects in depressed patients. These findings support the key role of the amygdala-cingulate circuit in mood regulation in both healthy and depressed populations and suggest that rapid antidepressant treatment may target the enhancement of amygdala-ACC connectivity.


Assuntos
Transtorno Depressivo Maior , Adulto , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/tratamento farmacológico , Privação do Sono/diagnóstico por imagem , Tonsila do Cerebelo/diagnóstico por imagem , Giro do Cíngulo/diagnóstico por imagem , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Imageamento por Ressonância Magnética/métodos
18.
Anal Chem ; 95(24): 9314-9322, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37277958

RESUMO

Herein, the novel alloyed silver gold sulfur quantum dots (AgAuS QDs) with highly efficient near-infrared (NIR) electrochemiluminescence (ECL) emission at 707 nm were successfully prepared to construct a biosensing platform for ultrasensitive detection of microRNA-222 (miRNA-222). Interestingly, AgAuS QDs revealed excellent ECL efficiency (34.91%) compared to that of Ag2S QDs (10.30%), versus the standard [Ru(bpy)3]2+/S2O82- system, which benefited from the advantages of abundant surface defects and narrow bandgaps by Au incorporation. Additionally, an improved localized catalytic hairpin self-assembly (L-CHA) system was developed to display an increased reaction speed by improving the local concentration of DNA strands, which addressed the obstacles of time-consuming traditional CHA systems. As a proof of concept, based on AgAuS QDs as an ECL emitter and improved localized CHA systems as a signal amplification strategy, a "signal on-off" ECL biosensor was developed to exhibit a superior reaction rate and excellent sensitivity with a detection limit of 10.5 aM for the target miRNA-222, which was further employed for the analysis of miRNA-222 from cancer cell (MHCC-97L) lysate. This work advances the exploration of highly efficient NIR ECL emitters to construct an ultrasensitive biosensor for the detection of biomolecules in disease diagnosis and NIR biological imaging.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Pontos Quânticos , MicroRNAs/análise , Medições Luminescentes/métodos , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Ouro , Enxofre , Limite de Detecção
19.
Trends Cogn Sci ; 27(9): 814-832, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37286432

RESUMO

Depression is a common mental disorder characterized by heterogeneous cognitive and behavioral symptoms. The emerging research paradigm of functional connectomics has provided a quantitative theoretical framework and analytic tools for parsing variations in the organization and function of brain networks in depression. In this review, we first discuss recent progress in depression-associated functional connectome variations. We then discuss treatment-specific brain network outcomes in depression and propose a hypothetical model highlighting the advantages and uniqueness of each treatment in relation to the modulation of specific brain network connectivity and symptoms of depression. Finally, we look to the future promise of combining multiple treatment types in clinical practice, using multisite datasets and multimodal neuroimaging approaches, and identifying biological depression subtypes.


Assuntos
Conectoma , Humanos , Conectoma/métodos , Imageamento por Ressonância Magnética/métodos , Depressão/terapia , Encéfalo/diagnóstico por imagem , Neuroimagem
20.
Anal Chem ; 95(17): 7021-7029, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37081730

RESUMO

In this study, nitrogen-, sulfur-, and fluorine-codoped carbon dots (NSF-CDs) with high electrochemiluminescence (ECL) efficiency were developed as novel emitters to fabricate an ECL biosensor for sensitive detection of matrix metalloproteinase 2 (MMP-2). Impressively, compared to previously reported CDs, NSF-CDs with narrow band gap not only decreased the excitation voltage to reduce the side reaction and the damage on biomolecules but also had hydrogen bonds to vastly enhance the ECL efficiency. Furthermore, an improved exonuclease III (Exo III)-assisted nucleic acid amplification method was established to convert trace MMP-2 into a mass of output DNA, which greatly improved the target conversion efficiency and ECL signal. Hence, the ECL biosensor has realized the sensitive detection of MMP-2 proteins from 10 fg/mL to 10 ng/mL with a limit of detection of 6.83 fg/mL and has been successfully applied in the detection of MMP-2 from Hela and MCF-7 cancer cells. This strategy offered neoteric CDs as ECL emitters for sensitive testing of biomarkers in medical research.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Humanos , Metaloproteinase 2 da Matriz , Flúor , Medições Luminescentes/métodos , Nitrogênio/química , Carbono/química , Técnicas Biossensoriais/métodos , Enxofre/química , Pontos Quânticos/química , Técnicas Eletroquímicas/métodos , Limite de Detecção
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