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1.
J Cell Physiol ; : e31448, 2024 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-39308045

RESUMEN

N6-methyladenosine (m6A) is known to be crucial in various biological processes, but its role in sepsis-induced circulatory and cardiac dysfunction is not well understood. Specifically, mitophagy, a specialized form of autophagy, is excessively activated during lipopolysaccharide (LPS)-induced myocardial injury. This study aimed to investigate the impact of LPS-induced endotoxemia on m6A-RNA methylation and its role in regulating mitophagy in sepsis-induced myocardial dysfunction. Our research demonstrated that FTO (fat mass and obesity-associated protein), an m6A demethylase, significantly affects abnormal m6A modification in the myocardium and cardiomyocytes following LPS treatment. In mice, cardiac dysfunction and cardiomyocyte apoptosis worsened after adeno-associated virus serotype 9 (AAV9)-mediated FTO knockdown. Further analyses to uncover the cellular mechanisms improving cardiac function showed that FTO reduced mitochondrial reactive oxygen species, restored both basal and maximal respiration, and preserved mitochondrial membrane potential. We revealed that FTO plays a critical role in activating mitophagy by targeting BNIP3. Additionally, the cardioprotective effects of AAV-FTO were significantly compromised by mdivi-1, a mitophagy inhibitor. Mechanistically, FTO interacted with BNIP3 transcripts and regulated their expression in an m6A-dependent manner. Following FTO silencing, BNIP3 transcripts with elevated m6A modification levels in their coding regions were bound by YTHDF2 (YT521-B homology m6A RNA-binding protein 2), leading to mRNA destabilization and decreased BNIP3 protein levels. These findings highlight the importance of FTO-dependent cardiac m6A methylation in regulating mitophagy and enhance our understanding of this critical interplay, which is essential for developing therapeutic strategies to protect cardiac mitochondrial function, alleviate cardiac dysfunction, and improve survival during sepsis.

2.
Chem Commun (Camb) ; 58(98): 13632-13635, 2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36408907

RESUMEN

In this work, we introduce trimethylbromosilane (C3H9SiBr), which can protect lithium metal anodes via an in situ formed SEI layer while catalyzing the decomposition of Li2O2. As a result, lithium-oxygen batteries with C3H9SiBr offer a long cycle life of 110 cycles with a significantly reduced charging/discharging overpotential.

3.
Colloids Surf B Biointerfaces ; 41(2-3): 197-201, 2005 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-15737547

RESUMEN

Under the background of algae removal and growth inhibition by ultrasonic irradiation, the effects of ultrasonic irradiation on removal of Microcystis, the concentration variation of microcystins (MC) produced by Microcystis in Microcystis suspension, and sonochemical degradation of microcystins in water, were studied in the paper. The results showed that ultrasonic irradiation could efficiently inhibit the growth of Microcystis, and ultrasonic irradiation shorter than 5 min would not introduce the increase of microcystins dissolved in Microcystis suspension simultaneity. Also, microcystins dissolved in Microcystis suspension would not increase as ultrasonic power increasing. Further research showed that microcystins were effectively degraded in ultrasonic fields. After 20 min ultrasonic irradiation at 150 kHz and 30 W, the removal rate of microcystins reached 70%.


Asunto(s)
Microcystis/fisiología , Péptidos Cíclicos/biosíntesis , Toxinas Bacterianas/biosíntesis , Toxinas Bacterianas/farmacocinética , Biodegradación Ambiental , Eucariontes/fisiología , Cinética , Microcistinas , Microcystis/efectos de la radiación , Péptidos Cíclicos/farmacocinética , Ultrasonido , Microbiología del Agua
4.
Colloids Surf B Biointerfaces ; 36(2): 115-21, 2004 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-15261016

RESUMEN

Ultrasonic signals propagated through medium were directly applied to unicellular cyanobacterium cell surfaces to investigate the biological effects induced by ultrasound. The gas-vacuolate cyanobacterium Microcystis aeruginosa and the gas-vacuole negative cyanobacterium Synechococcus PCC 7942 responded differently to ultrasound. When M. aeruginosa was irradiated by 1.7 MHz ultrasound at 0.6 W cm(-2) every day, it showed a decrease of nearly 65% in biomass increment, and this group's generation time increased twice as much as the control. While Synechococcus culture irradiated every day still grew as fast as the control, and its final biomass was as much as the control. The value of the electric conductivity change (Deltasigma) sharply increased in Microcystis suspension during the exposure process, which revealed more ultrasonic cavitation yield in liquid related to the gas-vacuolate cyanobacteria. The relative malondialdehyde (MDA) content, a quantitative indicator of lipid peroxidation, increased by 65% in Microcystis cells and 9% in Synechoccus cells after ultrasonic irradiation. Moreover, the membrane permeability, quantified by measuring the relative amount of electrolyte leaking out of cells, increased to more than 60% in the Microcystis cells. The results indicated that Microcystis cells were susceptible to ultrasonic stress. According to Rayleigh-Plesset's bubble activation theory, 1.7 MHz ultrasound approached the eigenfrequency of gas-vacuolate cells. The present investigation suggested the importance of the cavitational effect relative to intracellular gas-vacuoles in the loss of cell viability. In summary, 1.7 MHz ultrasonic irradiation was effective in preventing water-bloom forming cyanobacteria from growing rapidly due to changes in the functioning and integrity of cellular and subcellular structures.


Asunto(s)
Microcystis/efectos de la radiación , Ultrasonido , Vacuolas/efectos de la radiación , Biomasa , Recuento de Células , Membrana Celular/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Conductividad Eléctrica/efectos adversos , Gases/efectos de la radiación , Cinética , Peroxidación de Lípido/efectos de la radiación , Malondialdehído/análisis , Malondialdehído/efectos de la radiación , Microcystis/citología , Microcystis/crecimiento & desarrollo , Permeabilidad/efectos de la radiación , Synechococcus/citología , Synechococcus/crecimiento & desarrollo , Synechococcus/efectos de la radiación
5.
Ultrason Sonochem ; 11(1): 43-6, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14624987

RESUMEN

The degradation process and mechanism of p-chlorophenol in water using high frequency ultrasound (1.7 mHz) was investigated in this paper. The p-chlorophenol was degraded successfully in the high frequency ultrasonic device with low consumption of energy. The degradation effect was improved by increasing the solution concentration. No products or intermediate products were detected in the reaction mixture by the analytic methods of MS and 1H-NMR after ultrasonic irradiation. The dominant degradation mechanism is high temperature pyrolysis in ultrasonic cavities rather than free radical oxidation, and the experimental results can be explained completely according to pyrolysis mechanism.


Asunto(s)
Clorofenoles/efectos de la radiación , Ultrasonido , Abastecimiento de Agua/análisis , Clorofenoles/química , Cinética , Espectrometría de Masas , Oxidación-Reducción , Espectrofotometría Ultravioleta
6.
Ultrasonics ; 54(8): 2178-83, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25001053

RESUMEN

To solve the difficulty of introducing traditional ultrasonic transducers to welding molten pool, high frequency current is used to modulate plasma arc and ultrasonic wave is excited successfully. The characteristics of the excited ultrasonic field are studied. The results show that the amplitude-frequency response of the ultrasonic emission is flat. The modulating current is the main factor influencing the ultrasonic power and the sound pressure depends on the variation of arc plasma stream force. Experimental study of the welding structure indicates grain refinement by the ultrasonic emission of the modulated arc and the test results showed there should be an energy region for the arc ultrasonic to get best welding joints.

7.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 4941-4, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17946663

RESUMEN

Implanted nerve stimulation offers many advantages to improve the QOL (quality of life) of the patients suffering from nervous system diseases such as Parkinson's disease and epilepsy. Secondary battery begins to be used instead of primary secondary, service life of the implanted device is extended and the device becomes smaller and lighter. For charging the secondary battery fit in the body, a transcutaneous charger is designed. Two coupling coils designed specially are used to transmit and receive energy. With the mentioned coupling coils, the charger attains 15 mA charge current and the charge requirement is satisfied.


Asunto(s)
Terapia por Estimulación Eléctrica , Electrodos Implantados , Epilepsia/rehabilitación , Enfermedad de Parkinson/rehabilitación , Piel/patología , Suministros de Energía Eléctrica , Electrónica Médica , Diseño de Equipo , Corazón Artificial , Cuerpo Humano , Humanos , Modelos Estadísticos , Tejido Nervioso/patología , Sistema Nervioso Periférico , Radiación
8.
Environ Toxicol ; 18(6): 413-7, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14608611

RESUMEN

p-Chlorophenol (4-CP) is a recalcitrant organic pollutant that is biologically toxic in industrial wastewater. A high-frequency ultrasonic device operated at 1.7 MHz was designed and used successfully to degrade 4-CP. Iodine liberation in the KI aqueous solution confirmed that effective cavitation occurred under the high-frequency ultrasonic irradiation. No products or intermediate products were detected following the sonochemical degradation by 1H-nuclear magnetic resonance spectrum and mass spectrum after ultrasonic irradiation. It was concluded that the dominant degradation mechanism was high-temperature pyrolysis to inorganic products in ultrasonic cavities rather than free-radical oxidation.


Asunto(s)
Clorofenoles/química , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Residuos Industriales , Yodo/análisis , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ultrasonido
9.
Artículo en Inglés | MEDLINE | ID: mdl-15244327

RESUMEN

Ultrasonic irradiations at high frequency of 1.7 MHz and low frequency of 20 kHz were tested to prevent cyanobacteria Spirulina platensis from bloom. The inhibition effectiveness at 1.7 MHz was much greater than that at 20 kHz. The cyanobacteria biomass was reduced by 63% after 5 min ultrasonic irradiation at 1.7 MHz, whereas three days were needed for the tested cyanobacteria to recover its original density. However, longer exposure time did not significantly enhance the inhibition. It was observed after ultrasonic irradiation that the gas vesicles in cells collapsed, which may result in cyanobacterial precipitation and photosynthetic inhibition. The concentration of chlorophyll a (Chla) was reduced and its biosynthesis was delayed in a 4-day continuous culture. The fluorescence spectra at 77K of phycobilisome (PBS) and absorption spectra of intact cells in vivo showed that light energy transfer in PBS was inhibited and phycocyanin (PC) was damaged much more acutely compared with Chla. These results indicated that 5 min ultrasonic irradiation at 1.7 MHz every third day might be an effective and economic operation mode for practical application.


Asunto(s)
Proteínas Bacterianas , Ultrasonido , Purificación del Agua/métodos , Clorofila/análisis , Clorofila/biosíntesis , Clorofila A , Dinámica Poblacional , Spirulina , Microbiología del Agua
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