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1.
ACS Sens ; 9(1): 424-432, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38214465

RESUMEN

The biomarker 3-nitrotyrosine (3-NT) is widely recognized as an indicator of renal oxidative stress injury, making its detection crucial for the early identification of renal insufficiency. This study presents the design and synthesis of a tetraphenylstyrene imidazole derivative (TIPE-MI), which is utilized to create a supramolecular probe in conjunction with cucurbit[8]uril (Q[8]) through host-guest interactions. The resulting supramolecular self-assembly exhibits excellent optical properties and has been employed for the specific detection of 3-NT through fluorescence quenching. The introduction of 3-NT resulted in a decreased fluorescence intensity of the yellow fluorescent probe, which gradually transitioned from bright yellow to light yellow and then became colorless as the 3-NT concentration was increased. A portable detection platform was devised to augment the efficiency of detection. In order to facilitate biological applications, we have substantiated the probe's exceptional precision in detecting 3-NT in biological samples, encompassing human serum and plasma. The probe also exhibited negligible cytotoxicity. The accumulation of the probe in renal cells elicited a fluorescence signal, thereby indicating the prospective viability of this system for visual detection with renal cytocompatibility.


Asunto(s)
Hidrocarburos Aromáticos con Puentes , Colorantes Fluorescentes , Tirosina/análogos & derivados , Humanos , Estudios Prospectivos , Espectrometría de Fluorescencia
2.
Chem Commun (Camb) ; 59(93): 13851-13854, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37936519

RESUMEN

Fluorescent carbon quantum dots (CQDs) were synthesized from cucurbit[7]uril (Q[7]) and 2,2-bis(hydroxymethyl)propionic (DMPA) by a hydrothermal method. The Q[7]-DMPA complex was confirmed by X-ray crystallography. The CQDs showed blue fluorescence, photostability, and ionic strength stability. They were used to detect histamine with a low limit of 2.33 × 10-6 M.


Asunto(s)
Histamina , Puntos Cuánticos , Carbono/química , Puntos Cuánticos/química , Colorantes Fluorescentes/química
3.
Inorg Chem ; 62(49): 20467-20476, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38019638

RESUMEN

Solid-state materials with efficient room-temperature phosphorescence (RTP) emission have been widely used in materials science, and organic RTP-emitting systems with heavy-metal doping in aqueous solutions have attracted much attention in recent years. A novel supramolecular interaction was induced by host-guest assembly using cucurbit[7]uril (Q[7]) as the host and brominated naphthalimide phosphor as the guest. This interaction was further enhanced through synergistic chelation stimulated by analytical silver ion complexation. This approach facilitated the system's structural rigidity, intersystem crossing, and oxygen shielding. We achieved deep red phosphorescence emission in aqueous solution and ambient conditions along with quantitative determination of silver ions. The new complex exhibited good reversible thermoresponsive behavior and was successfully applied for the first time to target phosphorescence imaging of silver ions in the mitochondria of A549 cancer cells. These results are beneficial for constructing novel RTP systems with stimulus-responsive luminescence in aqueous solution, contributing to future research in bioimaging, detection, optical sensors, and thermometry materials.

4.
Bioresour Technol ; 389: 129816, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37793553

RESUMEN

This research comprehensively investigates the co-pyrolysis of sewage sludge (SS) and waste tobacco stem (WTS). Various SS and WTS ratios (1:0, 0.75:0.25, 0.50:0.50, 0.25:0.75, and 0:1) were tested over a range of heating rates (30 °C to 800 °C). Apparent activation energies were calculated using model-free methods, and the co-pyrolysis mechanism was described with the master plot method. Results suggest that SS and WTS co-pyrolysis follows power-law models (P3, P4). Among blends, S75W25 exhibited optimal synergy, with the lowest activation energy required for the pyrolysis reactions and inhibits CO2 emissions. S75W25's pyrolysis gas primarily contained acids (e.g., ethylxanthogenacetic acid, acetic acid), hydrocarbons (e.g., supraene, cyclopropyl carbinol), and other compounds (e.g., CO2, pyrazine, pyridine, indole). ANN was utilized to forecast the temperature-mass loss relationships in co-pyrolysis, with the optimal model being ANN21, yielding a high correlation coefficient (R2 = 0.99999). This study offers guidance for the efficient utilization of waste SS and WTS.


Asunto(s)
Nicotiana , Aguas del Alcantarillado , Dióxido de Carbono , Pirólisis , Cinética , Redes Neurales de la Computación
5.
J Control Release ; 362: 58-69, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37595666

RESUMEN

Asthenozoospermia, characterized by poor sperm motility, is a common cause of male infertility. Improving energy metabolism and alleviating oxidative stress through drug regimens are potential therapeutic strategies. In this study, we observed upregulated miR-24-3p levels in asthenozoospermia spermatozoa, contributing to energy metabolism disorder and oxidative stress by reducing GSK3ß expression. Thus, reducing miR-24-3p levels using drugs is expected to improve sperm motility. The blood-testis barrier (BTB) protects the testis from xenobiotics and drugs. In this study, we found that Sertoli cell-derived small extracellular vesicles (SC-sEV) can traverse the BTB and enter germ cells. We successfully loaded miR-24-3p inhibitor into SC-sEV, creating the nano-drug SC-sEV@miR-24-3p inhibitor, which effectively delivers miR-24-3p inhibitor into germ cells. In a gossypol-induced mouse asthenozoospermia model, administration of SC-sEV@miR-24-3p inhibitor significantly improved sperm motility, in vitro fertilization success, and blastocyst formation rates. As anticipated, it also improved the litter size of asthenozoospermia mice. These results suggest that SC-sEV@miR-24-3p inhibitor holds promise as a potential clinical treatment for asthenospermia.


Asunto(s)
Astenozoospermia , Vesículas Extracelulares , MicroARNs , Humanos , Masculino , Ratones , Animales , Células de Sertoli/metabolismo , Astenozoospermia/genética , Astenozoospermia/metabolismo , Motilidad Espermática , Barrera Hematotesticular/metabolismo , Semen/metabolismo , Espermatozoides/metabolismo , Células Germinativas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Vesículas Extracelulares/metabolismo
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 303: 123165, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37490841

RESUMEN

White light emitting materials have broad application prospects in fields such as displays, lighting devices, etc., but developing such materials faces considerable challenges. In this study, 1,3,5-tris[4-(pyridine-4-butyl)phenyl]benzene derivative (BTPY) was synthesized and a supramolecular assembly with AIE properties named BTPY@Q[7] was prepared with cucurbit[7]uril (Q[7]). Furthermore, by adding rhodamine 6G (R6G) to it, and controlling its ratio with R6G, a dual-emission white light system (0.33, 0.33) was synthesized and used for white light emitting materials as well as anti-counterfeiting fields. In addition, based on the BTPY@Q[7]-R6G system, a light harvesting system in aqueous phase was constructed, with an energy transfer efficiency (ΦET) of 26.19 % and an antenna effect (AE) of 10.21. Interestingly, the supramolecular self-assembly can also be used as a fluorescent probe, specifically recognize Fe(CN)63- ions in water, with a detection limit of 2.5 × 10-8 M.

7.
Anal Chim Acta ; 1254: 341095, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37005021

RESUMEN

Picric acid (PA) is a lethal explosive substance that is easily soluble in water and harmful to the environment. Here, a supramolecular polymer material BTPY@Q[8] with aggregation induced emission (AIE) was prepared by supramolecular self-assembly of cucurbit uril (Q[8]) and 1,3,5-tris[4-(pyridin-4-yl) phenyl] benzene derivative (BTPY), which exhibited aggregation-induced fluorescence enhancement. To this supramolecular self-assembly, the addition of a number of nitrophenols was found to have no obvious effect on the fluorescence, however on addition of PA, the fluorescence intensity underwent a dramatic quench. For PA, BTPY@Q[8] had sensitive specificity and effective selectivity. Based on this, a quick and simple on-site visual PA fluorescence quantitative detection platform was developed using smart phones, and the platform was used to monitor temperature. Machine learning (ML) is a popular pattern recognition technology, which can accurately predict the results from data. Therefore, ML has much more potential for analyzing and improving sensing data than the widely used statistical pattern recognition method. In the field of analytical science, the sensing platform offers a reliable method for the quantitative detection of PA that can be applied to other analytes or micropollutant screening.

8.
ACS Appl Mater Interfaces ; 15(3): 4668-4676, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36640109

RESUMEN

The host-guest interaction between hexamethyl cucurbit[5]uril (HmeQ[5]) and 1,4-diaminobenzene (DB) was investigated, and a new low-molecular-weight supramolecular gel was prepared by a simple heating/mixing cooling method. The structure and properties of the supramolecular gel were characterized. Results revealed that DB molecules did not enter the cavity of HmeQ[5] and that hydrogen bonding between the carbonyl group at the HmeQ[5] port and the DB amino groups, together with dipole-dipole interactions and outer wall interactions, were the main driving forces for the formation of the supramolecular gel. The HmeQ[5]/DB gel system exhibits temperature sensitivity. The phosphor 6-bromo-2-naphthol (BrNp) was embedded in the gel to give the gel fluorescent phosphorescence double emission. The double emission ability at room temperature can be attributed to the ordered microstructure of the supramolecular gel, which effectively avoids the nonradiative transition of BrNp. Meanwhile, HmeQ[5]/DB-BrNp has good biocompatibility and low biotoxicity, which is compatible with HeLa cells to achieve cytoplasmic staining of HeLa in the red channel. The supramolecular gels constructed by this supramolecular assembly strategy not only have good temperature sensitivity but also extend the application of Q[n]s in biomedical fields.


Asunto(s)
Hidrogeles , Naftoles , Humanos , Hidrogeles/química , Temperatura , Células HeLa
9.
Bioresour Technol ; 360: 127539, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35777640

RESUMEN

Tobacco stems (TS) are tobacco residues produced, whereby the assessment of the pyrolysis kinetics of TS is critical to realize high-value utilization of agricultural residues. Firstly, a thermogravimetric analyzer was employed to perform the non-isothermal pyrolysis of TS at various heating rates. Then, the deconvolution function by Asym2sig showed that the pyrolysis of TS can be accurately modeled for three parallel decomposition fractions. Furthermore, the pyrolysis product was analyzed using fourier transform infrared spectrometer (FTIR). The results showed that the average activation energy evaluated by the isoconversion methods exhibited the highest average activation energy of 191.762 kJ·mol-1 for lignin (LG), followed by 189.268 kJ·mol-1 for cellulose (CL) and then 176.357 kJ·mol-1 for hemicellulose (HC). Based on the experimental results, the pre-exponential factors and reaction models for HC, CL and LG were also calculated and developed separately. From thermodynamic standpoint, raw materials for bioenergy generation can be derived from TS.


Asunto(s)
Nicotiana , Pirólisis , Biomasa , Celulosa/química , Cinética , Lignina/química , Termogravimetría
10.
J Agric Food Chem ; 70(19): 5784-5793, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35506583

RESUMEN

In order to prevent and control the effects of pesticide residues on human health and the ecological environment, the rapid, highly sensitive, and selective detection of multiple pesticide residues has become an urgent problem to be solved. Herein, a lab-on-a-molecule probe based on a host-guest complex (ThT@Q[8] probe) has been developed to simultaneously analyze multiple aromatic pesticides under single wavelength excitation, such as fuberidazole, thiabendazole, carbendazim, thidiazuron, and tricyclazole. The fluorescence titration spectra of the ThT@Q[8] probe with the five pesticides mentioned above showed that the fluorescence intensity exhibited a good linear correlation with the pesticide concentration and the limit of detection was as low as 10-7 M. Because the ThT@Q[8] probe exhibits diverse fluorescence color changes to the five pesticides studied under a 365 nm ultraviolet lamp, we fabricated a single probe used to detect multiple analytes in the RGB triple channel by extracting the RGB variations. Principal component analysis and linear discriminant analysis proved that the ThT@Q[8] probe can recognize and distinguish five pesticides and can be applied at different concentrations. In real samples, the ThT@Q[8] probe recognized and distinguished five pesticides in tap water and Huaxi River water. The 1H NMR spectra results proved that a charge-transfer complex of ThT and pesticides in the Q[8] cavity may be formed. Moreover, we selected a test strip as a carrier to detect pesticides. The results indicate it can be used to quickly and conveniently detect different pesticides due to the rapid color change. Besides, the ThT@Q[8] probe has good cell permeability and can be used to detect pesticide residues in living cells. This work has laid the foundation for the qualitative and quantitative multitarget detection of pesticide residues.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Humanos , Sondas Moleculares/análisis , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Espectrometría de Fluorescencia/métodos , Agua/análisis
11.
Mol Biol Rep ; 49(6): 4929-4941, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35025029

RESUMEN

N6-methyladenosine (m6A), the methylation targeting the N6 position of adenosine, is the most common internal modification of mRNA in eukaryotes. Considering the roles of m6A in regulating gene expression, the investigation of m6A roles in the biological processes including cell renewal, differentiation, apoptosis, and invasion of cancer cells has become a hot research topic. There are three kinds of protein involved in m6A regulation. The methyltransferases and demethylases cooperatively regulate the m6A levels, while the m6A reading proteins recognize the m6A sites and mediate multiple m6A-dependent biological functions including mRNA splicing, transfer, translation, and degradation. At present, a large number of studies have found that the changes of m6A levels in tumor cells play a very important role in the occurrence and development of tumors, as well as metastasis and invasion of tumor cells. This review summarizes the different roles of m6A modification in the occurrence and development of various cancers, and discusses the possibility of choosing the m6A related proteins as potential therapeutic targets.


Asunto(s)
Adenosina , Neoplasias , Adenosina/análogos & derivados , Adenosina/metabolismo , Humanos , Metilación , Neoplasias/metabolismo , ARN Mensajero/genética
12.
Bioresour Technol ; 347: 126402, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34826563

RESUMEN

The evaluation of pyrolysis kinetics for waste industrial hemp stem (IHS) is essential to achieve the high-value utilization of agricultural waste. In present study, firstly, non-isothermal pyrolysis experiments of IHS were performed at different heating rates using a thermogravimetric analyzer. Then, the kinetic triplets (apparent activation energy, pre-exponential factor, and reaction mechanism) of the three pseudo components for IHS (hemicellulose, cellulose, and lignin) were determined by a three-parallel-reaction model. Moreover, the pyrolysis products were also characterized via FTIR and SEM. The results showed that the apparent activation energies of hemicellulose, cellulose and lignin were 86.523, 113.257 and 197.961 kJ/mol, respectively; the pre-exponential factors were 6.887 × 107, 8.179 × 109 and 1.801 × 1015 s-1, respectively; and the reaction mechanism functions were f(α) = α1.35629(1-α)0.34832[-ln(1-α)]-1.20128, f(α) = α3.42900(1-α)0.01288[-ln(1-α)]-2.84445, f(α) = α0.68738(1-α)3.09313[-ln(1-α)]-1.58522, respectively. The release temperature for volatile products of IHS pyrolysis was mainly between 440 and 840 K. IHS as an agricultural waste is a suitable feedstock to produce renewable energy.


Asunto(s)
Cannabis , Pirólisis , Biomasa , Cinética , Lignina , Termogravimetría
13.
Theranostics ; 11(16): 7640-7657, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34335955

RESUMEN

Background: Since primary prostate cancer (PCa) can advance to the life-threatening metastatic PCa, exploring the molecular mechanisms underlying PCa metastasis is crucial for developing the novel targeted preventive strategies for decreasing the mortality of PCa. RNA N6-methyladenosine (m6A) is an emerging regulatory mechanism for gene expression and its specific roles in PCa progression remains elusive. Methods: Western blotting, quantitative real-time PCR and immunohistochemical analyses were used to detect target gene expression in PCa cells in vitro and prostate tissues from patients. RNA immunoprecipitation was conducted to analyze the specific binding of mRNA to the target protein. Migration and invasion assays were used to assess the migratory capacities of cancer cells. The correlation between target gene expression and survival rate of PCa patients was analyzed based the TCGA database. Results: We found that total RNA N6-methyladenosine (m6A) modification levels were markedly upregulated in human PCa tissues due to increased expression of methyltransferase like 3 (METTL3). Further studies revealed that the migratory and invasive capacities of PCa cells were markedly suppressed upon METTL3 knockdown. Mechanistically, METTL3 mediates m6A modification of USP4 mRNA at A2696, and m6A reader protein YTHDF2 binds to and induces degradation of USP4 mRNA by recruiting RNA-binding protein HNRNPD to the mRNA. Decrease of USP4 fails to remove the ubiquitin group from ELAVL1 protein, resulting in a reduction of ELAVL1 protein. Lastly, downregulation of ELAVL1 in turn increases ARHGDIA expression, promoting migration and invasion of PCa cells. Conclusions: Our findings highlight the role of METTL3 in modulating invasion and metastasis of PCa cells, providing insight into promising therapeutic strategies for hindering PCa progressing to deadly metastases.


Asunto(s)
Metiltransferasas/genética , Neoplasias de la Próstata/metabolismo , Adenosina/análogos & derivados , Adenosina/genética , Adenosina/metabolismo , Movimiento Celular/genética , Proliferación Celular/genética , Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/genética , Silenciador del Gen/fisiología , Humanos , Masculino , Metiltransferasas/metabolismo , Invasividad Neoplásica/genética , Metástasis de la Neoplasia/genética , Próstata/metabolismo , Próstata/patología , Neoplasias de la Próstata/genética , ARN Mensajero/genética , Proteínas de Unión al ARN/metabolismo , Proteasas Ubiquitina-Específicas/genética
14.
Exp Neurol ; 344: 113805, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34242631

RESUMEN

Mild behavioral impairment (MBI), which can include compulsive behavior, is an early sign of Alzheimer's disease (AD), but its underlying neural mechanisms remain unclear. Here, we show that 3-5-month-old APP/PS1 mice display obsessive-compulsive disorder (OCD)-like behavior. The number of parvalbumin-positive (PV) interneurons and level of high gamma (γhigh) oscillation are significantly decreased in the striatum of AD mice. This is accompanied by enhanced ß-γhigh coupling and firing rates of putative striatal projection neurons (SPNs), indicating decorrelation between PV interneurons and SPNs. Local field potentials (LFPs) simultaneously recorded in prefrontal cortex (PFC) and striatum (Str) demonstrate a decrease in γhigh-band coherent activity and spike-field coherence in corticostriatal circuits of APP/PS1 mice. Furthermore, levels of GABAB receptor (GABABR), but not GABAA receptor (GABAAR), and glutamatergic receptors, were markedly reduced, in line with presymptomatic AD-related behavioral changes. These findings suggest that MBI occurs as early as 3-5 months in APP/PS1 mice and that altered corticostriatal synchronization may play a role in mediating the behavioral phenotypes observed.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Conducta Compulsiva/fisiopatología , Cuerpo Estriado/fisiopatología , Interneuronas/fisiología , Vías Nerviosas/fisiopatología , Corteza Prefrontal/fisiopatología , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animales , Conducta Compulsiva/metabolismo , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones , Ratones Transgénicos , Vías Nerviosas/metabolismo , Corteza Prefrontal/metabolismo , Presenilinas/genética , Receptores de GABA-B/metabolismo
15.
Bioresour Technol ; 249: 983-991, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29145126

RESUMEN

In this paper, the effects of temperature and CO2 content on CO2 reduction (utilization) efficiency and physicochemical properties of pyrolysis/gasification biochar briquettes were investigated. The CO2 reduction (utilization) efficiency (CRE) reached the peak value of 74.9% in a 10% CO2/90% N2 atmosphere at 600 °C. The crackings of hydroxyl, CC bonds, methyl and methylene groups of biochars briquette were enhanced by high temperature and CO2. The increase of CO2 concentration was beneficial for developing biochar microporosity, but not conductive to enhance higher heating value, volume density and durability of biochar briquette. To get a higher CRE and make feasible biochar briquettes are the primary goal for this work. Therefore, the optimal introduced CO2 to biomass ratio is calculated to be 135 g/kg for experiments done with 10% CO2 with N2 at 600 °C.


Asunto(s)
Carbón Orgánico , Madera , Biomasa , Dióxido de Carbono , Temperatura
16.
Sci Rep ; 7(1): 2406, 2017 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-28546556

RESUMEN

To improve the recovery of copper, the viscosity of copper molten slag is decreased by the reduction of magnetic iron, which, in turn, accelerates the settling and separation of copper droplets from the slag. A new technology is proposed in which waste cooking oil is used as a reductant to reduce magnetic iron in the copper smelting slag and consequently reduce carbon emissions in the copper smelting process. A kinetic model of the reduction of magnetic iron in copper slag by waste cooking oil was built using experimental data, and the accuracy of the model was verified. The results indicated that the magnetic iron content in the copper slag decreased with increasing reduction time and an increase in temperature more efficiently reduced magnetic iron in the copper slag. The magnetic iron in the copper slag gradually transformed to fayalite, and the viscosity of the copper molten slag decreased as the magnetic iron content decreased during the reduction process. The reduction of magnetic iron in the copper molten slag using waste cooking oil was a first-order reaction, and the rate-limiting step was the mass transfer of Fe3O4 through the liquid boundary layer.


Asunto(s)
Cobre , Grasas Insaturadas en la Dieta/análisis , Hierro , Algoritmos , Cobre/química , Hierro/química , Cinética , Modelos Teóricos , Temperatura , Viscosidad , Difracción de Rayos X
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