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1.
Proc Natl Acad Sci U S A ; 120(33): e2305928120, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37552758

RESUMEN

The Sangdanlin section in southern Tibet represents a geologic Rosetta stone to constrain the initiation of the India-Asia collision from its sedimentary and paleomagnetic records. However, geoscientists have arrived at fundamentally divergent interpretations surrounding the age of the strata and its paleomagnetic record. Here, we report paleontologic, petrographic, and paleomagnetic data from the Sangdanlin section that recognize the sequence as a thrust complex containing interlaced Barremian-Albian (Early Cretaceous) and Paleocene strata, each separated by thrust faults. Recognizing two complexly interwoven formations of distinctly different ages contradicts a continuous stratigraphic superposition. Assigning an Early Cretaceous, instead of Paleocene, age to the units collected for paleomagnetic data revises paleogeographic models thereby supporting a large (2,000 to 3,000 km) extent of Greater India, with collision initiating at 55 ± 5 Ma in the western Himalayas. A contiguous plate in the Neotethys Ocean precludes that Asia's southern margin was built through a succession of accreted terrains.

2.
Nano Lett ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958407

RESUMEN

Piwi-interacting RNAs (piRNAs) are small noncoding RNAs that repress transposable elements to maintain genome integrity. The canonical catalytic hairpin assembly (CHA) circuit relies on random collisions of free-diffused reactant probes, which substantially slow down reaction efficiency and kinetics. Herein, we demonstrate the construction of a spatial-confined self-stacking catalytic circuit for rapid and sensitive imaging of piRNA in living cells based on intramolecular and intermolecular hybridization-accelerated CHA. We rationally design a 3WJ probe that not only accelerates the reaction kinetics by increasing the local concentration of reactant probes but also eliminates background signal leakage caused by cross-entanglement of preassembled probes. This strategy achieves high sensitivity and good specificity with shortened assay time. It can quantify intracellular piRNA expression at a single-cell level, discriminate piRNA expression in tissues of breast cancer patients and healthy persons, and in situ image piRNA in living cells, offering a new approach for early diagnosis and postoperative monitoring.

3.
Nano Lett ; 24(21): 6312-6319, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38752550

RESUMEN

We present a dimensional regulating charge transfer strategy to achieve an enhanced electrochemiluminescence (ECL) by constructing a one-dimensional pyrene-based covalent organic framework (1D-COF). The dual-chain-like edge architecture in 1D-COF facilitates the stabilization of aromatic backbones, the enhancement of electronic conjugations, and the decrease of energy loss. The 1D-COF generates enhanced anodic (92.5-fold) and cathodic (3.2-fold) signals with tripropylamine (TPrA) and K2S2O8 as the anodic and cathodic coreactants, respectively, compared with 2D-COF. The anodic and cathodic ECL efficiencies of 1D-COF are 2.08- and 3.08-fold higher than those of 2D-COF, respectively. According to density functional theory (DFT), the rotational barrier energy (ΔE) of 1D-COF enhances sharply with the increase of dihedral angle, suggesting that the architecture in 1D-COF restrains the intramolecular spin of aromatic chains, which facilitates the decrease of nonradiative transitions and the enhancement of ECL. Furthermore, 1D-COF can be used to construct an ECL biosensor for sensitive detection of dopamine.

4.
Nano Lett ; 24(7): 2360-2368, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38347661

RESUMEN

Accurate and sensitive analysis of circulating tumor cells (CTCs) in human blood provides a non-invasive approach for the evaluation of cancer metastasis and early cancer diagnosis. Herein, we demonstrate the controllable assembly of a quantum dot (QD)-based aptasensor guided by CRISPR/Cas12a for direct measurement of CTCs in human blood. We introduce a magnetic bead@activator/recognizer duplex core-shell structure to construct a multifunctional platform for the capture and direct detection of CTCs in human blood, without the need for additional CTC release and re-identification steps. Notably, the introduction of magnetic separation ensures that only a target-induced free activator can initiate the downstream catalysis, efficiently avoiding the undesired catalysis triggered by inappropriate recognition of the activator/recognizer duplex structure by crRNAs. This aptasensor achieves high CTC-capture efficiency (82.72%) and sensitive detection of CTCs with a limit of detection of 2 cells mL-1 in human blood, holding great promise for the liquid biopsy of cancers.


Asunto(s)
Células Neoplásicas Circulantes , Puntos Cuánticos , Humanos , Células Neoplásicas Circulantes/patología , Puntos Cuánticos/química , Sistemas CRISPR-Cas/genética , Biopsia Líquida
5.
J Am Chem Soc ; 146(11): 7734-7742, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38447042

RESUMEN

Precisely controlling the architecture and spatial arrangement of plasmonic heterostructures offers unique opportunities to tailor the catalytic property, whereas the lack of a wet-chemistry synthetic approach to fabricating nanostructures with high-index facets limits their practical applications. Herein, we describe a universal synthetic strategy to construct Au/Rh freestanding superstructures (SSs) through the selective growth of ordered Rh nanoarrays on high-index-faceted Au nanobipyramids (NBPs). This synthetic strategy works on various metal nanocrystal substrates and can yield diverse Au/Rh and Pd/Rh SSs. Especially, the obtained Au NBP/Rh SSs exhibit high photocatalytic activity toward N2 fixation as a result of the spatially separated architecture, local electric field enhancement, and the antenna-reactor mechanism. Both theoretical and experimental results reveal that the Au NBPs can function as nanoantennas for light-harvesting to generate hot charge carriers for driving N2 fixation, while the Rh nanoarrays can serve as the active sites for N2 adsorption and activation to synergistically promote the overall catalytic activity in the Au NBP/Rh SSs. This work offers new avenues to rationally designing and constructing spatially separated plasmonic photocatalysts for high-efficiency catalytic applications.

6.
Anal Chem ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953495

RESUMEN

Long noncoding RNAs (lncRNAs) act as the dynamic regulatory molecules that control the expression of genes and affect numerous biological processes, and their dysregulation is associated with tumor progression. Herein, we develop a fluorescent light-up aptasensor to simultaneously measure multiple lncRNAs in living cells and breast tissue samples based on the DNAzyme-mediated cleavage reaction and transcription-driven synthesis of light-up aptamers. When target lncRNAs are present, they can be recognized by template probes to form the active DNAzyme structures, initiating the T4 PNK-catalyzed dephosphorylation-triggered extension reaction to generate double-strand DNAs with the T7 promoter sequences. The corresponding T7 promoters can initiate the transcription amplification catalyzed by the T7 RNA polymerase to generate abundant Broccoli aptamers and malachite green aptamers, which can bind DFHBI-1T and MG to generate strong fluorescence signals. Taking advantage of the good selectivity of DNAzyme-mediated cleavage of lncRNAs, high amplification efficiency of T7 transcription-driven amplification reaction, and bright fluorescence of the RNA aptamer-fluorophore complex, this method exhibits high sensitivity with a detection limit of 21.4 aM for lncRNA HOTAIR and 18.47 aM for lncRNA MALAT1, and it can accurately measure multiple lncRNAs in both tumor cell lines and breast tissue samples, providing a powerful paradigm for biomedical research and early clinic diagnostics.

7.
Anal Chem ; 96(11): 4487-4494, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38451469

RESUMEN

O6-Methylguanine-DNA-methyltransferase (MGMT) is a demethylation protein that dynamically regulates the O6-methylguanine modification (O6 MeG), and dysregulated MGMT is implicated in various malignant tumors. Herein, we integrate demethylation-activated DNAzyme with a single quantum dot nanosensor to sensitively detect MGMT in breast tissues. The presence of MGMT induces the demethylation of the O6 MeG-caged DNAzyme and the restoration of catalytic activity. The activated DNAzyme then specifically cleaves the ribonucleic acid site of hairpin DNA to expose toehold sequences. The liberated toehold sequence may act as a primer to trigger a cyclic exponential amplification reaction for the generation of enormous signal strands that bind with the Cy5/biotin-labeled probes to form sandwich hybrids. The assembly of sandwich hybrids onto 605QD obtains 605QD-dsDNA-Cy5 nanostructures, inducing efficient FRET between the 605QD donor and Cy5 acceptor. Notably, the introduction of a mismatched base in hairpin DNA can greatly minimize the background and improve the signal-to-noise ratio. This nanosensor achieves a dynamic range of 1.0 × 10-8 to 0.1 ng/µL and a detection limit of 155.78 aM, and it can screen MGMT inhibitors and monitor cellular MGMT activity with single-cell sensitivity. Moreover, it can distinguish the MGMT level in tissues of breast cancer patients and healthy persons, holding great potential in clinical diagnostics and epigenetic research studies.


Asunto(s)
Carbocianinas , ADN Catalítico , Guanina/análogos & derivados , Puntos Cuánticos , Humanos , ADN Catalítico/metabolismo , O(6)-Metilguanina-ADN Metiltransferasa/metabolismo , ADN/química , Desmetilación
8.
Anal Chem ; 96(5): 2191-2198, 2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38282288

RESUMEN

N6-Methyladenine (6mdA) and N4-methylcytosine (4mdC) are the two most dominant DNA modifications in both prokaryotes and eukaryotes, but standard hybridization-based techniques cannot be applied for the 6mdA/4mdC assay. Herein, we demonstrate the silver-coordinated Watson-Crick pairing-driven three-dimensional (3D) DNA walker for locus-specific detection of genomic 6mdA/4mdC at the single-molecule level. 6mdA-DNA and 4mdC-DNA can selectively hybridize with the binding probes (BP1 and BP2) to form 6mdA-DNA-BP1 and 4mdC-DNA-BP2 duplexes. The 6mdA-C/4mdC-A mismatches cannot be stabilized by AgI, and thus, 18-nt BP1/BP2 cannot be extended by the catalysis of KF exonuclease. Through toehold-mediated strand displacement (TMSD), the signal probe (SP1/SP2) functionalized on the gold nanoparticles (AuNPs) can competitively bind to BP1/BP2 in 6mdA-DNA-BP1/4mdC-DNA-BP2 duplex to obtain SP1-18-nt BP1 and SP2-18-nt BP2 duplexes. The resulting DNA duplexes can act as the substrates of lambda exonuclease, leading to the cleavage of SP1/SP2 and the release of Cy3/Cy5 and 18-nt BP1/BP2. The released 18-nt BP1/BP2 can subsequently serve as the walker DNA, moving along the surface of the AuNP to activate dynamic 3D DNA walking and releasing abundant Cy3/Cy5. The released Cy3/Cy5 can be quantified by single-molecule imaging. This nanosensor exhibits high sensitivity with a limit of detection (LOD) of 9.80 × 10-15 M for 6mdA-DNA and 9.97 × 10-15 M for 4mdC-DNA. It can discriminate 6mdA-/4mdC-DNA from unmodified genomic DNAs, distinguish 0.01% 6mdA-/4mdC-DNA from excess unmethylated DNAs, and quantify 6mdA-/4mdC-DNA at specific sites in genomic DNAs of liver cancer cells and Escherichia coli plasmid cloning vector, providing a new platform for locus-specific analysis of 6mdA/4mdC in genomic DNAs.


Asunto(s)
Adenina/análogos & derivados , Carbocianinas , Citosina/análogos & derivados , Nanopartículas del Metal , Plata , Oro , Nanopartículas del Metal/química , ADN , Genómica , Exonucleasas
9.
Anal Chem ; 96(1): 599-605, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-38156620

RESUMEN

Circular RNAs (circRNAs) represent an emerging category of endogenous transcripts characterized by long half-life time, covalently closed structures, and cell-/tissue-specific expression patterns, making them potential disease biomarkers. Herein, we demonstrate the construction of fluorescent G-quadruplex nanowires for label-free and accurate monitoring of circular RNAs in breast cancer cells and tissues by integrating proximity ligation-rolling circle amplification cascade with lighting up G-quadruplex. The presence of target circRNA facilitates the SplintR ligase-mediated ligation of the padlock probe. Upon the addition of primers, the ligated padlock probe can serve as a template to initiate subsequent rolling circle amplification (RCA), generating numerous long G-quadruplex nanowires that can incorporate with thioflavin T (ThT) to generate a remarkably improved fluorescence signal. Benefiting from good specificity of SplintR ligase-mediated ligation reaction and exponential amplification efficiency of RCA, this strategy can sensitively detect target circRNA with a limit of detection of 4.65 × 10-18 M. Furthermore, this method can accurately measure cellular circRNA expression with single-cell sensitivity and discriminate the circRNA expression between healthy para-carcinoma tissues and breast cancer tissues, holding great potential in studying the pathological roles of circRNA and clinic diagnostics.


Asunto(s)
Neoplasias de la Mama , Nanocables , Humanos , Femenino , ARN Circular , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Colorantes Fluorescentes/química , Ligasas , Técnicas de Amplificación de Ácido Nucleico/métodos
10.
Anal Chem ; 96(19): 7738-7746, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38690966

RESUMEN

Telomerase is an important biomarker for early diagnosis of cancers, but current telomerase assays usually rely on measuring the extension products of telomerase substrates, which increases the assay complexity. More evidence indicates that human telomerase RNA (hTR), as a core component of telomerase, is positively correlated with the telomerase activity. Herein, we demonstrate the development of a duplex-specific nuclease (DSN)-propelled 3D quantum dot (QD) nanoassembly with two-step Föster resonance energy transfer (FRET) for the one-step sensing of hTR in breast cancer cells and tissues. This assay involves only one hairpin probe modified with a Cy5 at the sixth base from the 5'-biotin end and a BHQ2 at the 3'-terminus, which integrates three functions of target recognition, target recycling amplification, and signal readout. The anchoring of the hairpin probe on the 605QD surface results in the formation of a 3D 605QD-Cy5-probe-BHQ2 nanoassembly in which two-step FRET occurs among the 605QD, Cy5, and BHQ2 quencher. Notably, the formation of 605QD-Cy5-probe-BHQ2 nanoassembly facilitates the reduction of background signal and the increase of signal-to-background ratio due to its dense, highly oriented nucleic acid shell-induced steric hindrance effect. This assay can achieve one-step and rapid detection of hTR with a detection limit of 2.10 fM, which is the simplest and most rapid hTR assay reported so far. Moreover, this assay can efficiently distinguish single-base mismatched sequences, and it can discriminate the hTR level between breast cancer patients and healthy donors with a high accuracy of 100%, with great prospects for early diagnosis of cancers.


Asunto(s)
Neoplasias de la Mama , Transferencia Resonante de Energía de Fluorescencia , Puntos Cuánticos , ARN , Telomerasa , Humanos , Telomerasa/metabolismo , Telomerasa/análisis , Puntos Cuánticos/química , ARN/metabolismo , ARN/análisis , Femenino , Carbocianinas/química , Técnicas Biosensibles/métodos
11.
Anal Chem ; 96(13): 5323-5330, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38501982

RESUMEN

Oxidative DNA damage is closely associated with the occurrence of numerous human diseases and cancers. 8-Oxo-7,8-dihydroguanine (8-oxoG) is the most prevalent form of DNA damage, and it has become not only an oxidative stress biomarker but also a new epigenetic-like biomarker. However, few approaches are available for the locus-specific detection of 8-oxoG because of the low abundance of 8-oxoG damage in DNA and the limited sensitivity of existing assays. Herein, we demonstrate the elongation and ligation-mediated differential coding for label-free and locus-specific analysis of 8-oxoG in DNA. This assay is very simple without the involvement of any specific labeled probes, complicated steps, and large sample consumption. The utilization of Bsu DNA polymerase can specifically initiate a single-base extension reaction to incorporate dATP into the opposite position of 8-oxoG, endowing this assay with excellent selectivity. The introduction of cascade amplification reaction significantly enhances the sensitivity. The proposed method can monitor 8-oxoG with a limit of detection of 8.21 × 10-19 M (0.82 aM), and it can identify as low as 0.001% 8-oxoG damage from a complex mixture with excessive undamaged DNAs. This method can be further applied to measure 8-oxoG levels in the genomic DNA of human cells under diverse oxidative stress, holding prospect potential in the dynamic monitoring of critical 8-oxoG sites, early clinical diagnosis, and gene damage-related biomedical research.


Asunto(s)
ADN Polimerasa Dirigida por ADN , ADN , Guanina/análogos & derivados , Humanos , ADN/genética , ADN Polimerasa Dirigida por ADN/metabolismo , Daño del ADN , Biomarcadores , Reparación del ADN
12.
Anal Chem ; 96(11): 4647-4656, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38441540

RESUMEN

Telomerase is a basic reverse transcriptase that maintains the telomere length in cells, and accurate and specific sensing of telomerase in living cells is critical for medical diagnostics and disease therapeutics. Herein, we demonstrate for the first time the construction of an enzymatically controlled DNA nanomachine with endogenous apurinic/apyrimidinic endonuclease 1 (APE1) as a driving force for one-step imaging of telomerase in living cells. The DNA nanomachine is designed by rational engineering of substrate probes and reporter probes embedded with an enzyme-activatable site (i.e., AP site) and their subsequent assembly on a gold nanoparticle (AuNP). Upon recognition and cleavage of the AP site in the substrate probe by APE1, the loop of the substrate probe unfolds, exposing telomeric primer (TP) with the 3'-OH end. Subsequently, the TP is elongated by telomerase at the 3'-OH end to generate a long telomeric product. The resultant telomeric product acts as a swing arm that can hybridize with a reporter probe to initiate the APE1-powered walking reaction, ultimately generating a significantly enhanced fluorescence signal. Notably, endogenous APE1 is used as the driving force of the DNA nanomachine, avoiding the introduction of exogenous auxiliary cofactors into the cellular microenvironment. Owing to the high kinetics and high amplification efficiency of the APE1-powered DNA nanomachine, this strategy enables one-step sensitive sensing of telomerase in vitro and in vivo. It can successfully discriminate telomerase activity between cancer cells and normal cells, screen telomerase inhibitors, and monitor the variations of telomerase activity in living cells, offering a prospective platform for molecular diagnostics and drug discovery.


Asunto(s)
Nanopartículas del Metal , Telomerasa , Humanos , Telomerasa/metabolismo , Oro/química , Nanopartículas del Metal/química , ADN/química , Células HeLa , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo
13.
Small ; : e2310289, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597769

RESUMEN

The high exciton binding energy (Eb) and sluggish surface reaction kinetics have severely limited the photocatalytic hydrogen production activity of carbon nitride (CN). Herein, a hybrid system consisting of nitrogen defects and Pt single atoms is constructed through a facile self-assembly and photodeposition strategy. Due to the acceleration of exciton dissociation and regulation of local electron density of Pt single atoms along with the introduction of nitrogen defects, the optimized Pt-MCT-3 exhibits a hydrogen production rate of 172.0 µmol h-1 (λ ≥ 420 nm), ≈41 times higher than pristine CN. The apparent quantum yield for the hydrogen production is determined to be 27.1% at 420 nm. The experimental characterizations and theoretical calculations demonstrate that the nitrogen defects act as the electron traps for the exciton dissociation, resulting in a decrease of Eb from 86.92 to 43.20 meV. Simultaneously, the stronger interaction between neighboring nitrogen defects and Pt single atoms directionally drives free electrons to aggregate around Pt single atoms, and tailors the d-band electrons of Pt, forming a moderate binding strength between Pt atoms and H* intermediates.

14.
Cell Commun Signal ; 22(1): 227, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38610001

RESUMEN

BACKGROUND: Laryngeal squamous cell carcinoma (LSCC) is one of the most common malignant tumors of the head and neck. Vasculogenic mimicry (VM) is crucial for tumor growth and metastasis and refers to the formation of fluid channels by invasive tumor cells rather than endothelial cells. However, the regulatory mechanisms underlying VM during the malignant progression of LSCC remain largely unknown. METHODS: Gene expression and clinical data for LSCC were obtained from the TCGA and Gene GEO (GSE27020) databases. A risk prediction model associated with VM was established using LASSO and Cox regression analyses. Based on their risk scores, patients with LSCC were categorized into high- and low-risk groups. The disparities in immune infiltration, tumor mutational burden (TMB), and functional enrichment between these two groups were examined. The core genes in LSCC were identified using the machine learning (SVM-RFE) and WGCNA algorithms. Subsequently, the involvement of bone morphogenetic protein 2 (BMP2) in VM and metastasis was investigated both in vitro and in vivo. To elucidate the downstream signaling pathways regulated by BMP2, western blotting was performed. Additionally, ChIP experiments were employed to identify the key transcription factors responsible for modulating the expression of BMP2. RESULTS: We established a new precise prognostic model for LSCC related to VM based on three genes: BMP2, EPO, and AGPS. The ROC curves from both TCGA and GSE27020 validation cohorts demonstrated precision survival prediction capabilities, with the nomogram showing some net clinical benefit. Multiple algorithm analyses indicated BMP2 as a potential core gene. Further experiments suggested that BMP2 promotes VM and metastasis in LSCC. The malignant progression of LSCC is promoted by BMP2 via the activation of the PI3K-AKT signaling pathway, with the high expression of BMP2 in LSCC resulting from its transcriptional activation by runt-related transcription factor 1 (RUNX1). CONCLUSION: BMP2 predicts poor prognosis in LSCC, promotes LSCC VM and metastasis through the PI3K-AKT signaling pathway, and is transcriptionally regulated by RUNX1. BMP2 may be a novel, precise, diagnostic, and therapeutic biomarker of LSCC.


Asunto(s)
Proteína Morfogenética Ósea 2 , Neoplasias de Cabeza y Cuello , Humanos , Subunidad alfa 2 del Factor de Unión al Sitio Principal , Células Endoteliales , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Transducción de Señal
15.
Mol Pharm ; 21(6): 2813-2827, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38752564

RESUMEN

Psoriasis, affecting 2-3% of the global population, is a chronic inflammatory skin condition without a definitive cure. Current treatments focus on managing symptoms. Recognizing the need for innovative drug delivery methods to enhance patient adherence, this study explores a new approach using calcipotriol monohydrate (CPM), a primary topical treatment for psoriasis. Despite its effectiveness, CPM's therapeutic potential is often limited by factors like the greasiness of topical applications, poor skin permeability, low skin retention, and lack of controlled delivery. To overcome these challenges, the study introduces CPM in the form of nanosuspensions (NSs), characterized by an average particle size of 211 ± 2 nm. These CPM NSs are then incorporated into a trilayer dissolving microneedle patch (MAP) made from poly(vinylpyrrolidone) and w poly(vinyl alcohol) as needle arrays and prefrom 3D printed polylactic acid backing layer. This MAP features rapidly dissolving tips and exhibits good mechanical properties and insertion capability with delivery efficiency compared to the conventional Daivonex ointment. The effectiveness of this novel MAP was tested on Sprague-Dawley rats with imiquimod-induced psoriasis, demonstrating efficacy comparable to the marketed ointment. This innovative trilayer dissolving MAP represents a promising new local delivery system for calcipotriol, potentially revolutionizing psoriasis treatment by enhancing drug delivery and patient compliance.


Asunto(s)
Administración Cutánea , Calcitriol , Sistemas de Liberación de Medicamentos , Agujas , Psoriasis , Ratas Sprague-Dawley , Psoriasis/tratamiento farmacológico , Animales , Calcitriol/análogos & derivados , Calcitriol/administración & dosificación , Ratas , Sistemas de Liberación de Medicamentos/métodos , Absorción Cutánea/efectos de los fármacos , Piel/metabolismo , Piel/efectos de los fármacos , Piel/patología , Tamaño de la Partícula , Masculino , Nanopartículas/química , Imiquimod/administración & dosificación , Suspensiones , Fármacos Dermatológicos/administración & dosificación , Fármacos Dermatológicos/farmacocinética , Parche Transdérmico
16.
Mol Biol Rep ; 51(1): 507, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622406

RESUMEN

BACKGROUND: Our previous research has demonstrated that hypoxic preconditioning (HPC) can improve spatial learning and memory abilities in adult mice. Adult hippocampal neurogenesis has been associated with learning and memory. The Neurogenic locus notch homolog protein (Notch) was involved in adult hippocampal neurogenesis, as well as in learning and memory. It is currently unclear whether the Notch pathway regulates hippocampal neuroregeneration by modifying the DNA methylation status of the Notch gene following HPC. METHOD: The HPC animal model and cell model were established through repeated hypoxia exposure using mice and the mouse hippocampal neuronal cell line HT22. Step-down test was conducted on HPC mice. Real-time PCR and Western blot analysis were used to assess the mRNA and protein expression levels of Notch1 and hairy and enhancer of split1 (HES1). The presence of BrdU-positive cells and Notch1 expression in the hippocampal dental gyrus (DG) were examined with confocal microscopy. The methylation status of the Notch1 was analyzed using methylation-specific PCR (MS-PCR). HT22 cells were employed to elucidate the impact of HPC on Notch1 in vitro. RESULTS: HPC significantly improved the step-down test performance of mice with elevated levels of mRNA and protein expression of Notch1 and HES1 (P < 0.05). The intensities of the Notch1 signal in the control group, the H group and the HPC group were 2.62 ± 0.57 × 107, 2.87 ± 0.84 × 107, and 3.32 ± 0.14 × 107, respectively, and the number of BrdU (+) cells in the hippocampal DG were 1.83 ± 0.54, 3.71 ± 0.64, and 7.29 ± 0.68 respectively. Compared with that in C and H group, the intensity of the Notch1 signal and the number of BrdU (+) cells increased significantly in HPC group (P < 0.05). The methylation levels of the Notch1 promoter 0.82 ± 0.03, 0.65 ± 0.03, and 0.60 ± 0.02 in the C, H, and HPC groups, respectively. The methylation levels of Notch1 decreased significantly (P < 0.05). The effect of HPC on HT22 cells exhibited similarities to that observed in the hippocampus. CONCLUSION: HPC may confer neuroprotection by activating the Notch1 signaling pathway and regulating its methylation level, resulting in the regeneration of hippocampal neurons.


Asunto(s)
Metilación de ADN , Hipocampo , Ratones , Animales , Metilación de ADN/genética , Bromodesoxiuridina/metabolismo , Hipocampo/metabolismo , Hipoxia/genética , Hipoxia/metabolismo , Receptores Notch/metabolismo , ARN Mensajero/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo
17.
Eur J Nutr ; 63(4): 1187-1201, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38366270

RESUMEN

PURPOSE: The aim of this study was to evaluate the effects of vitamin D and/or calcium supplementation on sleep quality in individuals with prediabetes. METHODS: A 24-week randomized controlled trial (RCT) was conducted in a 212 Chinese population with prediabetes. Participants were randomly assigned to four groups: vitamin D + calcium group (1600 IU/day + 500 mg/day, n = 53), vitamin D group (1600 IU/day, n = 54), calcium group (500 mg/day, n = 51), and control group (placebo, n = 54). The Pittsburgh Sleep Quality Index (PSQI) was used as the primary outcome to assess sleep quality. Questionnaires and fasting blood samples were collected at baseline and post-intervention for demographic assessment and correlation index analysis. RESULTS: After a 24-week intervention, a significant difference was observed in serum 25(OH)D concentration among the four groups (P < 0.05), and the total PSQI score in vitamin D + calcium group was lower compared to the preintervention levels. Subgroup analyses revealed improved sleep quality with calcium supplementation (P < 0.05) for specific groups, including women, individuals with a low baseline 25(OH)D level (< 30 ng/mL), and individuals in menopause. Moreover, correlation analysis revealed a negative correlation between the extent of change in sleep efficiency scores before and after the calcium intervention and the degree of change in insulin efficiency scores (r = - 0.264, P = 0.007), as well as the magnitude of change in islet beta cell function (r = - 0.304, P = 0.002). CONCLUSIONS: The combined intervention of vitamin D and calcium, as well as calcium interventions alone, exhibits substantial potential for improving sleep quality in individuals with prediabetes. CLINICAL TRIAL REGISTRATION: The trial was registered in August 2019 as ChiCTR190002487.


Asunto(s)
Suplementos Dietéticos , Estado Prediabético , Calidad del Sueño , Vitamina D , Humanos , Estado Prediabético/complicaciones , Estado Prediabético/dietoterapia , Estado Prediabético/sangre , Femenino , Vitamina D/sangre , Vitamina D/administración & dosificación , Masculino , Persona de Mediana Edad , Calcio de la Dieta/administración & dosificación , Adulto , Anciano , China , Método Doble Ciego , Vitaminas/administración & dosificación , Vitaminas/farmacología
18.
J Nat Prod ; 87(1): 132-140, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38157445

RESUMEN

Mylnudones A-G (1-7), unprecedented 1,10-seco-aromadendrane-benzoquinone-type heterodimers, and a highly rearranged aromadendrane-type sesquiterpenoid (8), along with four known analogs (9-12), were isolated from the liverwort Mylia nuda. Compounds 1-6 and 7, bearing tricyclo[6.2.1.02,7] undecane and tricyclo[5.3.1.02,6] undecane backbones, likely formed via a Diels-Alder reaction and radical cyclization, respectively. Their structures were determined by spectroscopic analysis, computational calculation, and single-crystal X-ray diffraction analysis. Dimeric compounds displayed cytoprotective effects against glutamic acid-induced neurological deficits.


Asunto(s)
Alcanos , Hepatophyta , Sesquiterpenos de Guayano , Sesquiterpenos , Hepatophyta/química , Estructura Molecular , Sesquiterpenos/farmacología , Sesquiterpenos/química , China
19.
Bioorg Chem ; 147: 107384, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38643568

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is a malignant tumor that is highly susceptible to metastasis, recurrence and resistance, and few therapeutic targets have been identified and proven effective. Herein, we demonstrated for the first time that Rap1b can positively regulate ESCC cell stemness, as well as designed and synthesized a novel class of Pt(IV) complexes that can effectively inhibit Raplb. In vitro biological studies showed that complex-1 exhibited stronger cytotoxicity than cisplatin and oxaliplatin against a variety of ESCC cells, and effectively reversed cisplatin-induced resistance of TE6 cells by increasing cellular accumulation of platinum and inhibiting cancer cell stemness. Significantly, complex-1 also exhibited strong ability to reversal cisplatin-induced cancer cell resistance and inhibit tumor growth in TE6/cDDP xenograft mice models, with a tumor growth inhibition rate of 73.3 % at 13 mg/kg and did not show significant systemic toxicity. Overall, Rap1b is a promising target to be developed as an effective treatment for ESCC. Complex-1, as the first Pt(IV) complex that can strongly inhibit Rap1b, is also worthy of further in-depth study.


Asunto(s)
Antineoplásicos , Proliferación Celular , Cisplatino , Resistencia a Antineoplásicos , Ensayos de Selección de Medicamentos Antitumorales , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Cisplatino/farmacología , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/patología , Animales , Resistencia a Antineoplásicos/efectos de los fármacos , Ratones , Proliferación Celular/efectos de los fármacos , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/patología , Relación Estructura-Actividad , Estructura Molecular , Relación Dosis-Respuesta a Droga , Ligandos , Ratones Desnudos , Proteínas de Unión al GTP rap/metabolismo , Proteínas de Unión al GTP rap/antagonistas & inhibidores , Ratones Endogámicos BALB C , Compuestos Organoplatinos/farmacología , Compuestos Organoplatinos/química , Compuestos Organoplatinos/síntesis química , Línea Celular Tumoral , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Neoplasias Experimentales/metabolismo , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química
20.
Cryobiology ; 115: 104864, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38387752

RESUMEN

The aim of this study was to investigate the therapeutic effect of cryoablation treatment in advanced NSCLC patients who had failed first-line chemotherapy. Eighty-seven patients from ten hospitals in China were enrolled into the study, forty-four patients received cryoablation treatment plus basic treatment (experimental group), and forty-three patients had basic treatment alone (control group). Follow-up was performed once every three months until the end of the study or the death of the patient. The primary endpoints were overall and post-intervention survival; secondary endpoints included tumor markers, solid tumor efficacy, and symptom changes before and after treatment. There was no significant difference in median OS between the two groups of patients (9.0 months vs 11.2 months, P = 0.583). The disease control rate (DCR) and living quality of the experimental group was higher than that of the control group. In terms of OS, indiscriminate use of cryoablation for such patients was not beneficial, though it could improve symptoms of patients. Cryoablation had a significant effect on selected advanced NSCLC patients after the failure of first-line chemotherapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Criocirugía , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Criocirugía/métodos , Masculino , Femenino , Persona de Mediana Edad , Neoplasias Pulmonares/cirugía , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Anciano , Estudios Prospectivos , Adulto , Resultado del Tratamiento , Insuficiencia del Tratamiento
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