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1.
BMC Chem ; 18(1): 91, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724989

RESUMEN

To improve the thermal and combustion properties of nanothermites, a design theory of changing the state of matter and structural state of the reactants during reaction was proposed. The Al/MoO3/KClO4 (Kp) nanothermite was prepared and the Al/MoO3 nanothermite was used as a control. SEM and XRD were used to characterize the nanothermites; DSC was used to test thermal properties; and constant volume and open combustion tests were performed to examine their combustion performance. Phase and morphology characterization of the combustion products were performed to reveal the mechanism of the aluminothermic reaction. The results show that the Al/MoO3/Kp nanothermite exhibited excellent thermal properties, with a total heat release of 1976 J·g- 1, increasing by approximately 33% of 1486 J·g- 1 of the Al/MoO3 nanothermite, and activation energy of 269.66 kJ·mol- 1, which demonstrated higher stability than the Al/MoO3 nanothermite (205.64 kJ·mol- 1). During the combustion test, the peak pressure of the Al/MoO3/Kp nanothermite was 0.751 MPa, and the average pressure rise rate was 25.03 MPa·s- 1, much higher than 0.188 MPa and 6.27 MPa·s- 1 of the Al/MoO3 nanothermite. The combustion products of Al/MoO3 nanothermite were Al2O3, MoO, and Mo, indicating insufficient combustion and incomplete reaction, whereas, the combustion products of Al/MoO3/Kp nanothermite were Al2O3, MoO, and KCl, indicating complete reaction. Their "coral-like" morphology was the effect of reactants solidifying after melting during the combustion process. The characterization of reactants and pressure test during combustion reveals the three stages of aluminothermic reaction in thermites. The excellent thermal and combustion performance of Al/MoO3/Kp nanothermite is attributed to the melt and decomposition of Kp into O2 in the third stage. This study provides new ideas and guidance for the design of high-performance nanothermites.

3.
Plants (Basel) ; 13(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38202450

RESUMEN

High temperature is the most important environmental factor limiting potato (Solanum tuberosum L.) yield. The tuber yield has been used to evaluate the heat tolerance of some potato cultivars, but potato yield was closely correlated with the maturation period. Therefore, it is necessary to employ different parameters to comprehensively analyze and evaluate potato tolerance to heat stress. This study aimed to investigate physiologic changes during growth and development, and develop accurate heat tolerance evaluation methods of potato cultivars under heat stress. About 93 cultivars (including foreign elite lines, local landraces and cultivars) were screened using an in vitro tuber-inducing system (continuous darkness and 8% sucrose in the culture medium) under heat stress (30 °C) and normal (22 °C) conditions for 30 days. The tuber yield and number decreased significantly under heat stress compared to the control. A total of 42 cultivars were initially selected depending on tuber formation, after in vitro screening, further testing of selected cultivars was conducted in ex vitro conditions. The screened cultivars were further exposed to heat stress (35 °C/28 °C, day/night) for 60 days. Heat stress led to an increase in the plant height growth rate, fourth internode growth rate, and membrane damage, and due to heat-induced damage to chloroplasts, decrease in chlorophyll biosynthesis and photosynthetic efficiency. Three principal components were extracted by principal component analysis. Correlation and regression analysis showed that heat tolerance is positively correlated with the plant height growth rate, fourth internode growth rate, the content of chlorophyll b, photosynthetic rate, stomatal conductance, transpiration rate, tuber number, and tuber yield, and negatively correlated with the cell membrane injury level. The nine traits are accurate and representative indicators for evaluating potato tolerance to heat stress and could determine a relatively high mean forecast accuracy of 100.0% for the comprehensive evaluation value. Through cluster analysis and screening, cultivar FA, D73, and C132 had the highest heat comprehensive evaluation value, which could be further selected as heat-resistant varieties. This study provides insights into the different physiological mechanisms and accurate evaluation methods of potato cultivars under heat stress, which could be valuable for further research and breeding.

4.
Plant Physiol Biochem ; 202: 107983, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37611488

RESUMEN

Gene regulation via intragenic sequences is becoming more recognized in many eukaryotes. However, the intragenic sequences mediated gene expressions in response to environmental stimuli have been largely uncharacterized. Here, we showed that the first intron of RrKSN from the Rosa rugosa cultivar 'Purple branch' had a positive effect on RrKSN expression, and the effect depends on its position and orientation. Further analyses revealed that the four adjacent cis-elements (T)CGATT/AATCG(A) within the first intron were critical for the positive regulation, and the RrKSN promotion was significantly suppressed with mutations of these elements. These cis-elements were further evidenced as binding sites for RrARR1, the homologous of Arabidopsis type-B ARABIDOPSIS RESPONSE REGULATOR 1 (ARR1) transcription factor. The first intron-mediated RrKSN expression was enhanced with over-expressing of RrARR1, but abolished with RrARR1 silencing in rose seedlings. Moreover, the expression difference of RrKSN between 16°C and 28°C was eliminated along with RrARR1-silencing. Taken together, these results suggested both RrARR1 and its binding elements are required for the first intron-mediated RrKSN expression in response to varying temperatures. Therefore, our results reveal a unique intragenic regulation mechanism of gene expression by which plants perceive the signal of ambient temperature in rose.


Asunto(s)
Rosa , Rosa/genética , Rosa/fisiología , Intrones , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas , Transcripción Genética , Regulación de la Expresión Génica de las Plantas , Temperatura , Citocininas/metabolismo , Factores de Transcripción/metabolismo , Flores/metabolismo
5.
CNS Neurosci Ther ; 29(12): 4043-4058, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37401033

RESUMEN

AIMS: Epidemiological studies in patients with neuropathic pain have demonstrated a strong association between neuropathic pain and psychiatric conditions such as anxiety. Preclinical and clinical work has demonstrated that electroacupuncture (EA) effectively alleviates anxiety-like behaviors induced by chronic neuropathic pain. In this study, a potential neural circuitry underlying the therapeutic action of EA was investigated. METHODS: The effects of EA stimulation on mechanical allodynia and anxiety-like behaviors in animal models of spared nerve injury (SNI) were examined. EA plus chemogenetic manipulation of glutamatergic (Glu) neurons projecting from the rostral anterior cingulate cortex (rACCGlu ) to the dorsal raphe nucleus (DRN) was used to explore the changes of mechanical allodynia and anxiety-like behaviors in SNI mice. RESULTS: Electroacupuncture significantly alleviated both mechanical allodynia and anxiety-like behaviors with increased activities of glutamatergic neurons in the rACC and serotoninergic neurons in the DRN. Chemogenetic activation of the rACCGlu -DRN projections attenuated both mechanical allodynia and anxiety-like behaviors in mice at day 14 after SNI. Chemogenetic inhibition of the rACCGlu -DRN pathway did not induce mechanical allodynia and anxiety-like behaviors under physiological conditions, but inhibiting this pathway produced anxiety-like behaviors in mice at day 7 after SNI; this effect was reversed by EA. EA plus activation of the rACCGlu -DRN circuit did not produce a synergistic effect on mechanical allodynia and anxiety-like behaviors. The analgesic and anxiolytic effects of EA could be blocked by inhibiting the rACCGlu -DRN pathway. CONCLUSIONS: The role of rACCGlu -DRN circuit may be different during the progression of chronic neuropathic pain and these changes may be related to the serotoninergic neurons in the DRN. These findings describe a novel rACCGlu -DRN pathway through which EA exerts analgesic and anxiolytic effects in SNI mice exhibiting anxiety-like behaviors.


Asunto(s)
Ansiolíticos , Electroacupuntura , Neuralgia , Ratas , Humanos , Ratones , Animales , Hiperalgesia/terapia , Giro del Cíngulo , Núcleo Dorsal del Rafe/metabolismo , Ratas Sprague-Dawley , Neuralgia/terapia , Neuralgia/metabolismo , Analgésicos , Ansiedad/terapia , Modelos Animales de Enfermedad
6.
Sci Adv ; 9(27): eadf6621, 2023 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-37406115

RESUMEN

Nuclear receptors (NRs) are implicated in the regulation of tumors and immune cells. We identify a tumor-intrinsic function of the orphan NR, NR2F6, regulating antitumor immunity. NR2F6 was selected from 48 candidate NRs based on an expression pattern in melanoma patient specimens (i.e., IFN-γ signature) associated with positive responses to immunotherapy and favorable patient outcomes. Correspondingly, genetic ablation of NR2F6 in a mouse melanoma model conferred a more effective response to PD-1 therapy. NR2F6 loss in B16F10 and YUMM1.7 melanoma cells attenuated tumor development in immune-competent but not -incompetent mice via the increased abundance of effector and progenitor-exhausted CD8+ T cells. Inhibition of NACC1 and FKBP10, identified as NR2F6 effectors, phenocopied NR2F6 loss. Inoculation of NR2F6 KO mice with NR2F6 KD melanoma cells further decreased tumor growth compared with NR2F6 WT mice. Tumor-intrinsic NR2F6 function complements its tumor-extrinsic role and justifies the development of effective anticancer therapies.


Asunto(s)
Linfocitos T CD8-positivos , Melanoma , Animales , Ratones , Inmunoterapia , Melanoma/genética , Proteínas Represoras/metabolismo
7.
Sensors (Basel) ; 23(10)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37430702

RESUMEN

Damping is an important factor contributing to errors in the measurement of rotational inertia using the torsion pendulum method. Identifying the system damping allows for minimizing the measurement errors of rotational inertia, and accurate continuous sampling of torsional vibration angular displacement is the key to realizing system damping identification. To address this issue, this paper proposes a novel method for measuring the rotational inertia of rigid bodies based on monocular vision and the torsion pendulum method. In this study, a mathematical model of torsional oscillation under a linear damping condition is established, and an analytical relationship between the damping coefficient, torsional period, and measured rotational inertia is obtained. A high-speed industrial camera is used to continuously photograph the markers on a torsion vibration motion test bench. After several data processing steps, including image preprocessing, edge detection, and feature extraction, with the aid of a geometric model of the imaging system, the angular displacement of each frame of the image corresponding to the torsion vibration motion is calculated. From the characteristic points on the angular displacement curve, the period and amplitude modulation parameters of the torsion vibration motion can be obtained, and finally the rotational inertia of the load can be derived. The experimental results demonstrate that the proposed method and system described in this paper can achieve accurate measurements of the rotational inertia of objects. Within the range of 0-100 × 10-3 kg·m2, the standard deviation of the measurements is better than 0.90 × 10-4 kg·m2, and the absolute value of the measurement error is less than 2.00 × 10-4 kg·m2. Compared to conventional torsion pendulum methods, the proposed method effectively identifies damping using machine vision, thereby significantly reducing measurement errors caused by damping. The system has a simple structure, low cost, and promising prospects for practical applications.

8.
Nature ; 620(7974): 651-659, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37468627

RESUMEN

Even among genetically identical cancer cells, resistance to therapy frequently emerges from a small subset of those cells1-7. Molecular differences in rare individual cells in the initial population enable certain cells to become resistant to therapy7-9; however, comparatively little is known about the variability in the resistance outcomes. Here we develop and apply FateMap, a framework that combines DNA barcoding with single-cell RNA sequencing, to reveal the fates of hundreds of thousands of clones exposed to anti-cancer therapies. We show that resistant clones emerging from single-cell-derived cancer cells adopt molecularly, morphologically and functionally distinct resistant types. These resistant types are largely predetermined by molecular differences between cells before drug addition and not by extrinsic factors. Changes in the dose and type of drug can switch the resistant type of an initial cell, resulting in the generation and elimination of certain resistant types. Samples from patients show evidence for the existence of these resistant types in a clinical context. We observed diversity in resistant types across several single-cell-derived cancer cell lines and cell types treated with a variety of drugs. The diversity of resistant types as a result of the variability in intrinsic cell states may be a generic feature of responses to external cues.


Asunto(s)
Antineoplásicos , Células Clonales , Resistencia a Antineoplásicos , Neoplasias , Humanos , Células Clonales/efectos de los fármacos , Células Clonales/metabolismo , Células Clonales/patología , Código de Barras del ADN Taxonómico , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/patología , RNA-Seq , Análisis de Expresión Génica de una Sola Célula , Células Tumorales Cultivadas , Antineoplásicos/farmacología
9.
Artículo en Inglés | MEDLINE | ID: mdl-37159978

RESUMEN

Qing Fei Yi Huo tablets (QFYHT) can relieve the clinical symptoms of acute bronchitis, and is widely prescribed in China. However, the quality standard of QFTHT lacks quantitative assessment. Therefore, it is crucial to develop an effective method for the extraction and analyses of its bioactive components.This study aimed to optimize the ultrasonic extraction of QFYHT and establish a method for the simultaneous quantification of 15 components. Box-Behnken Design (BBD) experiment was employed with three factors (solvent volume, extraction time and ultrasonic power) to optimize the extraction conditions, and the total content of 15 components was measured by high-performance liquid chromatography-diode array detector (HPLC-DAD) method. The total extracted content of 15 components was the highest when 100% methanol was used as the solvent, and the solvent volume was 22 mL, extraction time was 30 min and ultrasonic power was 350 w. The 15 components showed a good linear relationship (r ≥ 0.9998) within a concentration range. The precision, stability and repeatability of this method were satisfactory, and the average recovery rates ranged from 98.08% ∼ 102.87%. These findings demonstrate that optimization of extraction conditions by RSM can significantly improve the ultrasonic extraction rate of the 15 bioactive components of QFYHT. The quantification method is simple, accurate, reliable and practical, and can provide reference for improving the quality control of QFYHT.


Asunto(s)
Metanol , Extractos Vegetales , Solventes , Cromatografía Líquida de Alta Presión/métodos , Ultrasonido
10.
Proc Natl Acad Sci U S A ; 120(8): e2206878120, 2023 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-36791099

RESUMEN

SET is a multifunctional histone-binding oncoprotein that regulates transcription by an unclear mechanism. Here we show that SET enhances estrogen-dependent transcription. SET knockdown abrogates transcription of estrogen-responsive genes and their enhancer RNAs. In response to 17ß-estradiol (E2), SET binds to the estrogen receptor α (ERα) and is recruited to ERα-bound enhancers and promoters at estrogen response elements (EREs). SET functions as a histone H2 chaperone that dynamically associates with H2A.Z via its acidic C-terminal domain and promotes H2A.Z incorporation, ERα, MLL1, and KDM3A loading and modulates histone methylation at EREs. SET depletion diminishes recruitment of condensin complexes to EREs and impairs E2-dependent enhancer-promoter looping. Thus, SET boosts E2-induced gene expression by establishing an active chromatin structure at ERα-bound enhancers and promoters, which is essential for transcriptional activation.


Asunto(s)
Cromatina , Histonas , Cromatina/genética , Histonas/genética , Histonas/metabolismo , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Línea Celular Tumoral , Estrógenos/metabolismo , Estradiol/farmacología , Proteínas Oncogénicas/metabolismo , Transcripción Genética
11.
bioRxiv ; 2023 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-36711814

RESUMEN

Resistance to combination BRAF/MEK inhibitor (BRAFi/MEKi) therapy arises in nearly every patient with BRAFV600E/K melanoma, despite promising initial responses. Achieving cures in this expanding BRAFi/MEKi-resistant cohort represents one of the greatest challenges to the field; few experience additional durable benefit from immunotherapy and no alternative therapies exist. To better personalize therapy in cancer patients to address therapy relapse, umbrella trials have been initiated whereby genomic sequencing of a panel of potentially actionable targets guide therapy selection for patients; however, the superior efficacy of such approaches remains to be seen. We here test the robustness of the umbrella trial rationale by analyzing relationships between genomic status of a gene and the downstream consequences at the protein level of related pathway, which find poor relationships between mutations, copy number amplification, and protein level. To profile candidate therapeutic strategies that may offer clinical benefit in the context of acquired BRAFi/MEKi resistance, we established a repository of patient-derived xenograft models from heavily pretreated patients with resistance to BRAFi/MEKi and/or immunotherapy (R-PDX). With these R-PDXs, we executed in vivo compound repurposing screens using 11 FDA-approved agents from an NCI-portfolio with pan-RTK, non-RTK and/or PI3K-mTOR specificity. We identify dasatinib as capable of restoring BRAFi/MEKi antitumor efficacy in ~70% of R-PDX tested. A systems-biology analysis indicates elevated baseline protein expression of canonical drivers of therapy resistance (e.g., AXL, YAP, HSP70, phospho-AKT) as predictive of MAPKi/dasatinib sensitivity. We therefore propose that dasatinib-based MAPKi therapy may restore antitumor efficacy in patients that have relapsed to standard-of-care therapy by broadly targeting proteins critical in melanoma therapy escape. Further, we submit that this experimental PDX paradigm could potentially improve preclinical evaluation of therapeutic modalities and augment our ability to identify biomarker-defined patient subsets that may respond to a given clinical trial.

12.
J Ethnopharmacol ; 303: 115894, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36356715

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Shuangshen Pingfei formula (SSPF), a Chinese medicine prescription, has been prescribed to alleviate PF. However, little is known about the molecular mechanism underlying PF progression and the regulatory mechanism in SSPF. AIMS OF THE STUDY: To discriminate the molecular alterations underlying the development of pulmonary fibrosis (PF) and reveal the regulatory mechanism of Shuangshen Pingfei formula (SSPF). MATERIALS AND METHODS: An integrated analysis of a time-course pathology combined with proteomics and metabolomics was performed to investigate changes in body weight, survival rate, lung coefficient, histopathology, proteins, and metabolites of lung tissues at different time points upon bleomycin (BLM) exposure and SSPF treatment. RESULTS: The results showed that PF progression was characterized by gradually aggravated fibrosis accompanied by inflammation with extended exposure (7, 14, and 21 days). SSPF significantly attenuated lung fibrosis, as evidenced by increased weight, and reduced lung coefficients and fibrosis scores. Moreover, 368 common differentially expressed proteins (DEPs) were identified, and 102 DEPs were continuously and monotonically upregulated via proteomics among the three BLM treatments. The DEPs were principally involved in extracellular matrix (ECM) remodeling and arginine and proline (AP) metabolic reprogramming. Additionally, metabolomics analyses revealed that BLM exposure mainly affected six metabolism pathways, including 34 differentially regulated metabolites (DRMs). Furthermore, correlation analysis found that several DEPs and DRMs, including L-ornithine, S-adenosyl-L-methionine, ARG, and AOC1, were associated with arginine and proline metabolism, and 8,9-EET, 8,9-DHET, CYP2B, etc., were involved in arachidonic acid (AA) metabolism, suggesting that these two pathways play a critical role in the development of fibrosis. After SSPF treatment, the related protein expression and metabolic disorders were regulated, implying that SSPF provides potential solutions to target these pathways for benefit in the treatment of PF. CONCLUSION: Our data suggest that ECM remodeling, and metabolic reprogramming of AP and AA are distinctive features of PF development. Simultaneously, we confirmed that SSPF could effectively regulate metabolic disorders, indicating its potential clinical application for PF therapy. Our findings using multiple approaches provide a molecular-scale perspective on the mechanisms of PF progression and the amelioration of SSPF.


Asunto(s)
Fibrosis Pulmonar , Humanos , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/metabolismo , Proteómica , Bleomicina , Metabolómica , Prolina , Arginina
13.
Int J Mol Sci ; 23(13)2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35806340

RESUMEN

Pseudo-response regulators (PRRs) are the important genes for flowering in roses. In this work, clock PRRs were genome-wide identified using Arabidopsis protein sequences as queries, and their evolutionary analyses were deliberated intensively in Rosaceae in correspondence with angiosperms species. To draw a comparative network and flow of clock PRRs in roses, a co-expression network of flowering pathway genes was drawn using a string database, and their functional analysis was studied by silencing using VIGS and protein-to-protein interaction. We revealed that the clock PRRs were significantly expanded in Rosaceae and were divided into three major clades, i.e., PRR5/9 (clade 1), PRR3/7 (clade 2), and TOC1/PRR1 (clade 3), based on their phylogeny. Within the clades, five clock PRRs were identified in Rosa chinensis. Clock PRRs had conserved RR domain and shared similar features, suggesting the duplication occurred during evolution. Divergence analysis indicated the role of duplication events in the expansion of clock PRRs. The diverse cis elements and interaction of clock PRRs with miRNAs suggested their role in plant development. Co-expression network analysis showed that the clock PRRs from Rosa chinensis had a strong association with flowering controlling genes. Further silencing of RcPRR1b and RcPRR5 in Rosa chinensis using VIGS led to earlier flowering, confirming them as negative flowering regulators. The protein-to-protein interactions between RcPRR1a/RcPRR5 and RcCO suggested that RcPRR1a/RcPRR5 may suppress flowering by interfering with the binding of RcCO to the promoter of RcFT. Collectively, these results provided an understanding of the evolutionary profiles as well as the functional role of clock PRRs in controlling flowering in roses.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Rosa , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ritmo Circadiano/fisiología , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Rosa/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
14.
Mol Neurobiol ; 59(9): 5299-5311, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35696012

RESUMEN

Chronic pain, such as neuropathic pain, causes anxiety and other negative emotions, which aggravates the pain sensation and increases the risk of chronic pain over time. Dopamine receptor D1 (DRD1) and dopamine receptor D2 (DRD2) in the basolateral amygdala (BLA) have been implicated in mediating anxiety-related behaviors, but their potential roles in the BLA in neuropathic pain-induced anxiety have not been examined. Electroacupuncture (EA) is commonly used to treat chronic pain and emotional disorders, but it is still unclear whether EA plays a role in analgesia and anxiety relief through DRD1 and DRD2 in the BLA. Here, we used western blotting to examine the expression of DRD1 and DRD2 and pharmacological regulation combined with behavioral testing to detect anxiety-like behaviors. We observed that injection of the DRD1 antagonist SCH23390 or the DRD2 agonist quinpirole into the BLA contributed to anxiety-like behaviors in naive mice. EA also activated DRD1 or inhibited DRD2 in the BLA to alleviate anxiety-like behaviors. To further demonstrate the role of DRD1 and DRD2 in the BLA in spared nerve injury (SNI) model-induced anxiety-like behaviors, we injected the DRD1 agonist SKF38393 or the DRD2 antagonist sulpiride into the BLA. We found that both activation of DRD1 and inhibition of DRD2 could alleviate SNI-induced anxiety-like behaviors, and EA had a similar effect of alleviating anxiety. Additionally, neither DRD1 nor DRD2 in the BLA affected SNI-induced mechanical allodynia, but EA did. Overall, our work provides new insights into the mechanisms of neuropathic pain-induced anxiety and a possible explanation for the effect of EA treatment on anxiety caused by chronic pain.


Asunto(s)
Complejo Nuclear Basolateral , Dolor Crónico , Electroacupuntura , Neuralgia , Animales , Ansiedad/complicaciones , Ansiedad/terapia , Complejo Nuclear Basolateral/metabolismo , Dolor Crónico/terapia , Ratones , Neuralgia/metabolismo , Neuralgia/terapia , Receptores de Dopamina D1/metabolismo
15.
Dalton Trans ; 51(22): 8680-8687, 2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35607823

RESUMEN

Carbon dots (CDs), emerging as promising materials for optoelectronic and biomedical applications, are widely investigated due to their distinct merits of facile preparation, biocompatibility, and environment-friendliness. Here, a unique strategy based on surface engineering is proposed to modulate the photoluminescence (PL) of CDs in both aqueous solution and the solid state with good thermal cycling stability. For the typical blue emissive CD solution derived from citric acid and ethylenediamine, an intense green emission can be induced by adding Bi3+ due to the strong coordination ability of Bi3+ ions with carboxyl groups on the surface of CDs. A super facile synthesis approach (ultrafast at room-temperature) has been developed to fabricate the CDs@NaBiF4 nanocomposite, whose chemical structure and composition have been investigated in detail. For the solid nanocomposite, it not only preserves the strong blue emission from the intrinsic core state of CDs, but exhibits a new green emission from the surface state. The solid-state CDs@NaBiF4 nanocomposite exhibits good thermal stability and high resistance to thermal degradation under blue light excitation. The strategy via metal ion-mediated PL of CDs represents a new approach to control the optical properties of CDs, and provides more opportunities in solid-state lighting and biomedical applications.

16.
Artículo en Inglés | MEDLINE | ID: mdl-35397413

RESUMEN

Our previous studies showed that Shuangshen Pingfei Formula (SSPF) exhibited anti-fibrosis effect, but its biochemical changes at the metabolic level remain unclear. In this study, an integrative approach of gas chromatography-mass spectrometry (GC-MS) and ultra performance liquid chromatography-Q Exactive-mass spectrometry (UPLC-QE-MS)-based non-targeted metabolomics and multivariate statistical analysis was employed to explore the metabolic changes of serum samples from different stages of bleomycin-induced pulmonary fibrosis (PF) rats (PFRs: M7, M14, M21 and M28) treated with SSPF extracts. Potential biomarkers for PF were screened. Benzenebutanoic acid, pyroglutamic acid, cholic acid, 1-monopalmitin, succinic acid and palmitoleic acid may be potential biomarkers of the early inflammation stage of PF (M7-M14). 3,4-dimethylbenzoic acid, glutamic acid, glycine, proline, serine, taurine, etc. may be potential biomarkers for the advanced pulmonary fibrosis stage (M21-M28) of PF. The disturbance was mainly related to the disorder of lipid, amino acid metabolism. After SSPF treatment, the disorder was regulated and 67 metabolites were restored to a certain extent. Serine, proline, glutamine, 4-guanidinobutyric acid, phosphatidylethanolamine, lecithin and 9,10-epoxyoctadecene acids may be useful as biomarkers of the anti-fibrosis effect of SSPF.


Asunto(s)
Fibrosis Pulmonar , Animales , Biomarcadores , Bleomicina/efectos adversos , Cromatografía Líquida de Alta Presión/métodos , Metabolómica/métodos , Prolina , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/tratamiento farmacológico , Ratas , Serina/efectos adversos
17.
ACS Omega ; 7(8): 6834-6842, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35252677

RESUMEN

The development of red emission carbon dots with bright solid-state fluorescence would significantly broaden their application in optoelectronic devices and sensors. Herein, a red-emissive carbon dot-based nanocomposite has been synthesized through chemical bonding with cellulose films. The red emission originating from the surface states of carbon dots was maintained in the cellulose films. Due to the stable chemical bonding, the photoluminescence intensity and emission wavelength remained unchanged for 12 months, and the quantum yield of the composite was enhanced over 4 times. It also showed outstanding stability in water or weak acid-base environments under pHs ranging from 2 to 11. Therefore, the mechanism of chemical bonding that eliminated the defects and preserved the efficient radiative process through surface states was proposed.

18.
Small ; 18(13): e2106863, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35076167

RESUMEN

Carbonized polymer dots (CPDs) have received tremendous attention during the last decade due to their excellent fluorescent properties and catalytic performance. Doping CPDs with transition metal atoms accelerates the local electron flow in CPDs and improves the fluorescent properties and catalytic performance of the CPDs. However, the binding sites and the formation mechanisms of the transition-metal-atom-doped CPDs remain inconclusive. In this work, Mn2+ -ion-doped CPDs (Mn-CPDs) are synthesized by the hydrothermal method. The Mn2+ ions form MnO bonds that bridge the sp2 domains of carbon cores and increases the effective sp2 domains in the Mn-CPDs, which redshifts the fluorescence emission peak of the Mn-CPDs slightly. The Mn2+ ions form covalent bonds in the CPDs and remedy the oxygen vacancies of the CPDs, which cuts off the non-radiative-recombination process of the Mn-CPDs and increases the quantum yield of the Mn-CPDs to 70%. Furthermore, the MnO bonds accelerate the electron flow between adjacent sp2 domains and enhances the electron transport in the Mn-CPDs. Thus, the Mn-CPDs demonstrate excellent catalytic performance to activate hydrogen peroxide (H2 O2 ) and produce hydroxyl radicals (•OH) to degrade methylene blue (MB) and rhodamine B (RhB).


Asunto(s)
Polímeros , Puntos Cuánticos , Carbono/química , Transporte de Electrón , Fluorescencia , Polímeros/química , Puntos Cuánticos/química
19.
Cell Rep ; 37(5): 109913, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34731618

RESUMEN

Opiates produce a strong rewarding effect, but abstinence from opiate use emerges with severe negative emotions. Depression is one of the most frequent emotion disorders associated with opiate abstinence, which is thought to be a main cause for relapse. However, neurobiological bases of such an aversive emotion processing are poorly understood. Here, we find that morphine abstinence activates κ-opioid receptors (KORs) by increasing endogenous KOR ligand dynorphin expression in the amygdala, which in turn facilitates glutamate transporter 1 (GLT1) expression by activation of p38 mitogen-activated protein kinase (MAPK). Upregulation of GLT1 expression contributes to opiate-abstinence-elicited depressive-like behaviors through modulating amygdalar glutamatergic inputs to the nucleus accumbens (NAc). Intra-amygdala injection of GLT1 inhibitor DHK or knockdown of GLT1 expression in the amygdala significantly suppresses morphine-abstinence-induced depressive-like behaviors. Pharmacological and pharmacogenetic activation of amygdala-NAc projections prevents morphine-abstinence-induced behaviors. Overall, our study provides key molecular and circuit insights into the mechanisms of depression associated with opiate abstinence.


Asunto(s)
Amígdala del Cerebelo/metabolismo , Conducta Animal , Depresión/metabolismo , Transportador de Glucosa de Tipo 1/metabolismo , Ácido Glutámico/metabolismo , Morfina , Núcleo Accumbens/metabolismo , Receptores Opioides kappa/metabolismo , Síndrome de Abstinencia a Sustancias/metabolismo , Amígdala del Cerebelo/fisiopatología , Animales , Depresión/inducido químicamente , Depresión/fisiopatología , Depresión/psicología , Modelos Animales de Enfermedad , Dinorfinas/metabolismo , Potenciales Postsinápticos Excitadores , Transportador de Glucosa de Tipo 1/genética , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Vías Nerviosas/metabolismo , Vías Nerviosas/fisiopatología , Núcleo Accumbens/fisiopatología , Receptores Opioides kappa/genética , Transducción de Señal , Síndrome de Abstinencia a Sustancias/fisiopatología , Síndrome de Abstinencia a Sustancias/psicología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
20.
J Phys Chem Lett ; 12(19): 4530-4536, 2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-33961442

RESUMEN

Aggregation-induced luminescence quenching of carbon nanodots (CDs) is the main obstacle for their applications in solid-state light emitting devices. Herein, we developed a one-step synthesis of solid-state emissive CDs with surface aluminum-based polymerization by adding AlCl3 in citric acid and urea via a microwave-heating dehydration process. Due to the strong coordination ability of Al ions with N and O atoms, considerable steric hindrance of Al-based cross-linked polymerization was introduced on the surface of the CDs, which not only avoided aggregation of the green emissive carbon cores but also facilitated efficient energy transfer from the blue emissive polymerized surface to the green emissive carbon cores in aggregates, leading to enhanced green emissions with a photoluminescence quantum yield (PLQY) of 72.7% in the solid state.

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