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1.
Adv Sci (Weinh) ; : e2403028, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946620

RESUMO

Superhydrophobic surfaces (SHS) exhibit a pronounced ability to resist wetting. When immersed in water, water does not penetrate between the microstructures of the SHS. Instead, a thin layer of trapped gas remains, i.e., plastron. This fractional wetting is also known as the Cassie-Baxter state (CB). Impairment of superhydrophobicity occurs when water penetrates the plastron and, when complete wetting is achieved, a Wenzel state (W) results. Subsequent recovery back to CB state is one of the main challenges in the field of SHS wetting. Current methods for plastron recovery require complex mechanical or chemical integration, are time-consuming or lack spatial control. Here an on-demand, contact-less approach for performing facile transitions between these wetting states at micrometer length scales is proposed. This is achieved by the use of acoustic radiation force (ARF) produced by high-intensity focused ultrasound (HIFU). Switching from CB to W state takes <100 µs, while the local recovery back to CB state takes <45 s. To the best of authors knowledge, this is the first demonstration of ARF-induced manipulation of the plastron enabling facile two-way controlled switching of wetting states.

2.
Int Marit Health ; 75(2): 89-102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38949219

RESUMO

BACKGROUND: Saturation diving is a standard method of intervention for commercial diving during offshore operations. Current saturation procedures achieve a high level of safety with regards to decompression sickness but still put the divers under multiple stressors: 1) Environmental stress (long confinement, heat/cold, dense gases, high oxygen levels), 2) Work stress (muscular fatigue, psychological pressure, breathing equipment, etc.), 3) venous gas emboli associated with decompression, 4) Inflammation related to oxidative stress and microparticles. We present the results of a saturation divers monitoring campaign performed in the North Sea Danish sector, on the Tyra field, during 2022. The study was supported by TotalEnergies, the field operator, and performed by Boskalis Subsea Services, the diving contractor, onboard the diving support vessel Boka Atlantis. The objective was twofold: document the level of diving stress during saturation operations in the Danish sector, and compare the performances of two saturation procedures, the Boskalis and the NORSOK procedures. MATERIALS AND METHODS: Fourteen divers volunteered for the study. The monitoring package include weight and temperature measurements, psychomotor tests (objective evaluation) and questionnaires (subjective evaluation), Doppler bubble detection and bioimpedance. The results were presented in a radar diagram that provides a general view of the situation. RESULTS: The data were analysed along 3 dimensions: work and environmental, desaturation bubbles, oxidative stress and inflammation. The results showed little or no variations from the reference values. No bubbles were detected after excursion dives and the final decompression, except for two divers with a grade 1 after arriving at surface. No statistical difference could be found between the Boskalis and the NORSOK saturation procedures. CONCLUSIONS: At a depth of 40-50 msw corresponding to the Danish sector, the two saturation procedures monitored induce no or little stress to the divers. The divers know how to manage their diet, equilibrate their hydration and pace their effort. Data available on divers' post saturation period show a recovery over the 24-48 hours following the end of the decompression. Further research should focus on diving deeper than 100 msw where a greater stress can be anticipated.


Assuntos
Doença da Descompressão , Mergulho , Humanos , Mergulho/efeitos adversos , Mergulho/fisiologia , Mar do Norte , Adulto , Masculino , Saturação de Oxigênio/fisiologia , Pessoa de Meia-Idade , Estresse Fisiológico , Dinamarca , Monitorização Fisiológica/métodos
3.
Adv Sci (Weinh) ; : e2403366, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953394

RESUMO

Bubbles and foams are often removed via chemical defoamers and/or mechanical agitation. Designing surfaces that promote chemical-free and energy-passive bubble capture is desirable for numerous industrial processes, including mineral flotation, wastewater treatment, and electrolysis. When immersed, super-liquid-repellent surfaces form plastrons, which are textured solid topographies with interconnected gas domains. Plastrons exhibit the remarkable ability of capturing bubbles through coalescence. However, the two-step mechanics of plastron-induced bubble coalescence, namely, rupture (initiation and location) and subsequent absorption (propagation and drainage) are not well understood. Here, the influence of 1) topographical feature size and 2) gas fraction on bubble capture dynamics is investigated. Smaller feature sizes accelerate rupture while larger gas fractions markedly improve absorption. Rupture is initiated solely on solid domains and is more probable near the edges of solid features. Yet, rupture time becomes longer as solid fraction increases. This counterintuitive behavior represents unexpected complexities. Upon rupture, the bubble's moving liquid-solid contact line influences its absorption rate and equilibrium state. These findings show the importance of rationally minimizing surface feature sizes and contact line interactions for rapid bubble rupture and absorption. This work provides key design principles for plastron-induced bubble coalescence, inspiring future development of industrially-relevant surfaces for underwater bubble capture.

4.
Environ Technol ; : 1-11, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955504

RESUMO

As volatile organic compounds (VOCs), gaseous ethylbenzene has adverse effects on human health and ecology. Therefore, an effective degradation process is highly desirable. The Fenton process under UV 365 nm was selected as the first option to remove gaseous ethylbenzene in a bubble column reactor. The main parameters for the batch experiments were systematically studied, including H2O2 concentration, [H2O2]/[Fe2+], pH, UV wavelength, UV intensity, gaseous ethylbenzene concentration, gas flow rate, and process stability towards removal efficiency. The optimum conditions were found to be H2O2 concentration of 100 mmol·L-1, [H2O2]/[Fe2+] of 4, pH of 3.0, UV wavelength of 365 nm, UV power of 5 W, gas flow rate of 900 mL·min-1, and gaseous ethylbenzene concentration of 30 ppm, resulting in a removal efficiency of 76.3%. The study found that the Fenton process, when coupled with UV 365 nm, was highly effective in removing gaseous ethylbenzene. The degradation mechanism of gaseous ethylbenzene was proposed in the UV365/Fenton process based on EPR, radical quenching experiments, iron analysis, carbon balance, and GC-MS analysis. The results indicated that •OH played a crucial role in the process.

5.
Heliyon ; 10(12): e32671, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975126

RESUMO

Microbially induced nitrogen (N2) gas bubbles can desaturate subsurface areas and thus have been considered as an alternative ground improvement technique for mitigating soil liquefaction potential caused by earthquakes. However, the detailed mechanisms of subsurface N2 bubbles are not well understood and remain a subject of ongoing research. In this study, a transparent microfluidic device was utilized to mimic biological N2 gas bubble formation by nitrate-reducing bacteria and to visually characterize the entire process. During N2 gas formation, a limited number of bubble nucleation sites were identified, which gradually expanded upward through the preferential pore channels. N2 gas bubbles tended to create interconnected gas pockets rather than existing as evenly distributed small gas cavities. The degree of water saturation gradually reduced over a week as the bubbles were produced. The gas ganglia repeatedly grew until they reached the top boundary, which triggered a drastic expulsion of bubbles by ebullition. Despite fluctuations in saturation level, the residual saturation was maintained at around 73 %. Comparative experimental case studies of CO2 gas bubble formation were conducted to identify contrasting gas formation mechanisms. CO2 gas bubbles were generated via the abiotic decompression of a supersaturated CO2 solution under two distinct rates of pressure reduction. Rapid CO2 bubble formation led to uniform nucleation and 41 % residual saturation, while slower formation yielded 35 % due to stable liquid displacement by the gas front. This study highlights the potential of the microfluidic device as an experimental tool for visualizing subsurface gas formation mechanisms. The insights gained could further enhance and optimize geotechnical applications involving gas formation in highly saturated soils.

6.
Sci Rep ; 14(1): 14525, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914642

RESUMO

To achieve high-efficiency combustion of heavy fuel oil (HFO), this study investigated the combustion characteristics of methanol/HFO droplets with methanol content from 10 to 30% using the suspension method under ambient temperature from 923 to 1023 K. The combustion of methanol/HFO droplets was summarized as a two-phase process consisting of six typical stages, emphasizing liquid phase. Especially, the fluctuation evaporation stage, induced by frequent and intense puffing, was identified as prominent character. Both the ignition delay and lifetime of HFO and methanol/HFO droplets decreased with increasing ambient temperatures. For the methanol/HFO droplet, the ignition delay and droplet lifetime increased with the increasing methanol content. Prominently, compared to HFO, HM10 had the most significant reduction in droplet lifetime and TINL under the same operating conditions, which indicated that the addition of 10% methanol accelerated the combustion process and reduced soot generation. Additionally, the thermos-dynamic characteristics of methanol/HFO droplets were investigated. Puffing was primarily attributed to superheating of methanol and pyrolysis of heavy components in HFO, which resulted in active and passive rupture of bubbles. Similarity and maximum deformation were employed to qualitatively distinguish between them. The obtained findings aimed to develop a promising alternative fuel to reduce emissions and preserve energy.

7.
Ultrason Sonochem ; 107: 106942, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850641

RESUMO

The jet dynamics of a cavitation bubble near unequal-sized dual particles is investigated employing OpenFOAM, and the effects of the jets on the particles are quantitatively analyzed in terms of their pressure impacts. Different from single-particle cases, the necks that evolve between dual particles are closely linked to the formation mechanism of the jets. Based on the simulation results, the jet dynamics can be divided into five scenarios: (1) the contraction of the annular depression produced by the collision of the two necks causes the bubble to split into two daughter bubbles and generates a single jet inside each daughter bubble; (2) the annular depression impacts the particle, leading to the bubble to fracture and producing a single jet inside a daughter bubble; (3) the bubble is split by a single neck constriction and produces a single jet; (4) the bubble is split by a single neck constriction and generates two jets; and (5) the bubble is split by the contraction of two necks and produces four jets together with three daughter bubbles. As the bubble-particle distance or the radius ratio of the dual particles increases, the maximum force on the small particle generated by the bubble decreases.

8.
ACS Appl Mater Interfaces ; 16(26): 33336-33346, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38907693

RESUMO

Developing earth-abundant transition metal electrodes with high activity and durability is crucial for efficient and cost-effective hydrogen production. However, numerous studies in the hydrogen evolution reaction (HER) primarily focus on improving the inherent activity of catalysts, and the critical influence of gas-liquid countercurrent transport behavior is often overlooked. In this study, we introduce the concept of separate-path gas-liquid transport to alleviate mass transport losses for the HER by developing a novel hierarchical porous Ni-doped cobalt phosphide electrode (CoNix-P@Ni). The CoNix-P@Ni electrodes with abundant microvalleys and crack structures facilitate the gas-liquid cotransport by separating the bubble release and water supply paths. Visualization and numerical simulation results demonstrate that cracks primarily serve as water supply paths, with capillary pressure facilitating the transport of water from the cracks to the microvalleys. This process ensures the continuous wetting of electrolytes in the electrode, reduces hydrogen supersaturation near the active site, and increases hydrogen transport flux to the microvalleys for accelerating bubble growth. Additionally, the microvalleys act as preferential sites for bubble evolution, preventing bubble coverage on other active sites. By regulating the amount of nickel, the CoNi1-P@Ni electrode exhibited the smallest and densest microvalleys and cracks, achieving superior HER performance with an overpotential of 51 mV at 10 mA cm-2. The results offer a promising direction for constructing high-performance HER electrodes.

9.
Ultrason Sonochem ; 108: 106952, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38878714

RESUMO

The mechanism of generation of shock waves by the collapse of a cavitation bubble near a single particle or dual particles is numerically investigated using OpenFOAM. For the single-particle case, shock waves during bubble inception and jet impacting on the particle surface are revealed in detail. The pressure induced on the particle by the inception shock wave of the bubble decreases with increasing bubble-particle distance, and the pressure is proportional to 1/r1.26 (r being the distance from the center of the shock wave). For the dual particles, the evolution of the neck structure is closely related to the generation mechanism of the shock wave. At extremely close particle-bubble distances, two shock waves propagating in opposite directions are emitted outside and inside the bubble after two necks collide. At long particle-bubble distances, a shock wave is emitted after the neck contracts, and simultaneously the bubble splits into two daughter bubbles. The energy of the shock wave generated by the neck constriction (i.e., the pressure at its generation location) first increases and then decreases with increasing bubble-particle distance. For unequal-sized double particles, the size of the daughter bubble depends on the bubble-particle distance and the particle size. These findings provide new perspectives for understanding the damage sustained by hydro-mechanical components operating in sand-laden water flows.

10.
Nano Lett ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847360

RESUMO

In laser-based additive manufacturing (AM), porosity and unmelted metal powder are typically considered undesirable and harmful. Nevertheless in this work, precisely controlling laser parameters during printing can intentionally introduce controllable porosity, yielding a porous electrode with enhanced catalytic activity for the oxygen evolution reaction (OER). This study demonstrates that deliberate introduction of porosity, typically considered a defect, leads to improved gas molecule desorption, enhanced mass transfer, and increased catalytically active sites. The optimized P-93% electrode displays superior OER performance with an overpotential of 270 mV at 20 mA cm-2. Furthermore, it exhibits remarkable long-term stability, operating continuously for over 1000 h at 10 mA cm-2 and more than 500 h at 500 mA cm-2. This study not only provides a straightforward and mass-producible method for efficient, binder-free OER catalysts but also, if optimized, underscores the potential of laser-based AM driven defect engineering as a promising strategy for industrial water splitting.

11.
Nanomaterials (Basel) ; 14(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38869572

RESUMO

The alkaline oxygen evolution reaction (OER) remains a bottleneck in green hydrogen production owing to its slow reaction kinetics and low catalytic efficiencies of earth abundant electrocatalysts in the alkaline OER reaction. This study investigates the OER performance of hierarchically porous cobalt electrocatalysts synthesized using the dynamic hydrogen bubble templating (DHBT) method. Characterization studies revealed that electrocatalysts synthesized under optimized conditions using the DHBT method consisted of cobalt nanosheets, and hierarchical porosity with macropores distributed in a honeycomb network and mesopores distributed between cobalt nanosheets. Moreover, X-ray photoelectron spectroscopy studies revealed the presence of Co(OH)2 as the predominant surface cobalt species while Raman studies revealed the presence of the cubic Co3O4 phase in the synthesized electrocatalysts. The best performing electrocatalyst required only 360 mV of overpotential to initiate a current density of 10 mA cm-2, exhibited a Tafel slope of 37 mV dec-1, and stable OER activity over 24 h. The DHBT method offers a facile, low cost and rapid synthesis approach for preparation for highly efficient cobalt electrocatalysts.

12.
Ultrasonics ; 142: 107374, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38875881

RESUMO

This study investigates the size-dependent dynamics of bubbles and their interaction with soft boundaries under various ultrasound (US) conditions. We found that bubble behavior is influenced by size, with smaller bubbles displaying reduced inertial motion in similar ultrasound environments. Detailed analyses of three bubble sizes (1.5 µm, 15 µm, and 150 µm) next to a soft 1 kPa boundary revealed distinct patterns in radial oscillation, bubble center displacement, and boundary deflection for different ultrasound frequencies (5 kHz - 4 MHz). The smallest bubble maintained a spherical shape, while the largest experienced significant shape changes, indicative of impending jet formation. Investigating interactions at various frequencies highlighted the collapse tendency of the larger bubbles, showcasing maximum radial amplitude, displacement, and bubble wall velocity around its natural frequency. The presence of a soft boundary minimally affected radial amplitude and velocity, while the bubble displacement was contingent on the soft boundary modulus. Furthermore, boundary responses demonstrated that softer boundaries experienced less stress during bubble oscillations, exhibiting sharper peaks at resonance frequencies for larger bubbles. These findings provide valuable insights into optimizing ultrasound conditions for a variety of applications, highlighting the influence of bubble size and boundary properties on outcomes.

13.
J Environ Manage ; 363: 121328, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850916

RESUMO

Antibiotics and organic residues from Tetracycline (TC) and other pharmaceuticals administered to aquatic living organism have negative impacts on aquatic environment by killing-off non-target living organisms and developing antibiotic-resistant bacteria. In this study, Micro-Nano Bubble (MNB) system was used to remove TC residues. MNB system demonstrated good level of degradation efficiency, as resulted in experiment where in time of 100 min, the TC degraded at rate of 82.66% from its initial concentration of TC when the initial concentration was 1 mg/L. When the initial concentration was increased to 10 mg/L, MNB system degraded TC at 64.35% of their initial, this means MNB system demonstrated good level of efficiency for TC removal and indicated that it is more efficient in TC degradation under the conditions of low initial TC concentration and high availability of dissolved oxygen (DO). In the system as the temperature increased there was a significant decrease in DO saturation which was related to the TC complex structure that contain multiple function groups such as amino groups, hydroxyl and carboxyl which possess high strong affinity with oxygen that leads to their adsorption onto bubble surface. This study provides significant insights into the application of MNB system for the removal of organic residues within aquatic ecosystem and underscores the need for further exploration of MNB technology for environmental remediation.


Assuntos
Tetraciclina , Tetraciclina/química , Tetraciclina/análise , Poluentes Químicos da Água/química , Adsorção , Oxigênio/química , Antibacterianos/química
14.
FEBS Lett ; 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38880762

RESUMO

This study investigated how membrane thickness and tension modify the gating of KcsA potassium channels when simultaneously varied. The KcsA channel undergoes global conformational changes upon gating: expansion of the cross-sectional area and longitudinal shortening upon opening. Thus, membranes impose differential effects on the open and closed conformations, such as hydrophobic mismatches. Here, the single-channel open probability was recorded in the contact bubble bilayer, by which variable thickness membranes under a defined tension were applied. A fully open channel in thin membranes turned to sporadic openings in thick membranes, where the channel responded moderately to tension increase. Quantitative gating analysis prompted the hypothesis that tension augmented the membrane deformation energy when hydrophobic mismatch was enhanced in thick membranes.

15.
Plant Dis ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885024

RESUMO

Wet bubble disease (WBD) in Agaricus bisporus caused by Mycogone species imposes a substantial economic loss to mushroom production in China. Currently, fungicide application is the main method to control WBD. However, excessive use of fungicide is challenged by the appearance of resistance and food safety. Therefore, it is necessary to explore safe and efficient strategies to control WBD. Strain 9-13, isolated from the rhizosphere soil of Taxus chinensis, showed strong inhibitory activity against three Mycogone species. According to morphological and biochemical characteristics, and multilocus phylogenetic analysis, the strain was identified as Streptomyces nojiriensis. In addition, strain 9-13 extracts significantly inhibited mycelial growth and spore germination of M. perniciosa, M. rosea and M. xinjiangensis in vitro. Strain 9-13 and its extracts also exhibited broad-spectrum antifungal activities against 12 selected plant pathogenic fungi. Scanning electron microscopic observations showed that extracts destroyed mycelial structure, inducing mycelia to twist and shrink. Moreover, transmission electron microscopy revealed that extracts resulted in severe plasmolysis, rupture of cell membrane and a decrease in cell inclusions, and the cell wall appeared a rough and uneven surface. Notably, the extracts obviously reduced disease severity and incidence of WBD by from 83.85% to 87.32% in fruiting bodies and 77.36% in mushroom beds, and maintained fruiting time and color on harvested mushroom. Collectively, these results clearly indicate that S. nojiriensis 9-13 is a promising biocontrol agent to control WBD on A. bisporus.

16.
Phys Med Biol ; 69(13)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38843808

RESUMO

Objective.Super-resolution ultrasonography offers the advantage of visualization of intricate microvasculature, which is crucial for disease diagnosis. Mapping of microvessels is possible by localizing microbubbles (MBs) that act as contrast agents and tracking their location. However, there are limitations such as the low detectability of MBs and the utilization of a diluted concentration of MBs, leading to the extension of the acquisition time. We aim to enhance the detectability of MBs to reduce the acquisition time of acoustic data necessary for mapping the microvessels.Approach.We propose utilizing phase patterned waves (PPWs) characterized by spatially patterned phase distributions in the incident beam to achieve this. In contrast to conventional ultrasound irradiation methods, this irradiation method alters bubble interactions, enhancing the oscillation response of MBs and generating more significant scattered waves from specific MBs. This enhances the detectability of MBs, thereby enabling the detection of MBs that were undetectable by the conventional method. The objective is to maximize the overall detection of bubbles by utilizing ultrasound imaging with additional PPWs, including the conventional method. In this paper, we apply PPWs to ultrasound imaging simulations considering bubble-bubble interactions to elucidate the characteristics of PPWs and demonstrate their efficacy by employing PPWs on MBs fixed in a phantom by the experiment.Main results.By utilizing two types of PPWs in addition to the conventional ultrasound irradiation method, we confirmed the detection of up to 93.3% more MBs compared to those detected using the conventional method alone.Significance.Ultrasound imaging using additional PPWs made it possible to increase the number of detected MBs, which is expected to improve the efficiency of bubble detection.


Assuntos
Microbolhas , Imagens de Fantasmas , Ultrassonografia , Ultrassonografia/métodos , Meios de Contraste/química
17.
Chemosphere ; 362: 142582, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871192

RESUMO

This investigation elucidates the influence of micron-scale aeration bubbles on the improvement of anti-fouling characteristics within submerged membrane bioreactors (sMBRs). A systematic examination of sludge properties, hydraulic dynamics, and fouling tendencies revealed that the application of microbubble aeration, specifically at dimensions of 100 µm, 80 µm, and 30 µm, significantly reduced sludge electrostatic repulsion and augmented particle size distribution, as opposed to the utilization of coarse bubble aeration of 1 mm. Notably, the employment of 100 µm bubbles achieved a significant reduction in the proportion of smaller particles (<10 µm) and sludge viscosity, thereby facilitating a more homogenous and vigorous turbulence at the membrane interface. These optimized conditions were instrumental in the substantial reduction of membrane fouling, which was corroborated by the diminished rate of fouling, reduced resistance accumulation, and lesser foulant deposition. The investigation identified sludge particle size, turbulent kinetic energy, and shear stress as the predominant factors influencing the development of membrane fouling. The findings underscore the pronounced advantages of employing 100 µm-sized bubbles in aeration strategies, providing enhanced understanding for the optimization of aeration parameters to improve sMBR efficiency and maintenance.

18.
Cogn Neurodyn ; 18(3): 1167-1181, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38826667

RESUMO

This study explored selective exposure and confirmation bias in the choices participants made about which political videos to watch, and whether their political positions changed after they watched videos that either agreed with or opposed their positions on two controversial issues in South Korea: North Korea policy and social welfare policy. The participants completed questionnaires before and after they watched the videos, were asked to select thumbnails of videos before they watched any, and had their brain wave activity measured through electroencephalogram (EEG) as they watched both types of videos. The participants demonstrated selective exposure as they primarily selected video thumbnails with content that matched their political orientations, and they demonstrated confirmation bias as their questionnaire responses after they watched the videos indicated that their positions had hardened. There were also statistically significant differences in alpha, beta, sensory motor rhythm, low beta, mid beta, and fast alpha activity depending on the political orientation consistency between the participants and the videos. Future studies could expand this line of research beyond college students and beyond Asia, and longitudinal work could also be conducted to determine if the obtained patterns remain constant over time.

19.
Biol Pharm Bull ; 47(6): 1106-1112, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38839361

RESUMO

Ultrafine bubbles (UFBs), which are bubbles with diameters of less than 1 µm, are widely recognized for their ability to exist stably in liquid as a result of the effects of Brownian motion. In this study, we focused on hydrogen, known for its antioxidant potential, and explored the function of H2-filled UFBs, which encapsulate hydrogen, to determine their potential use as oral carriers for the delivery bioactive gases to living organisms. To this end, rats were orally administered ethanol to induce hepatic oxidative stress, and the effects of drinking H2-filled UFBs (H2 NanoGAS®) water for two weeks were evaluated to assess the reduction of oxidative stress. Continuous alcohol consumption was found to significantly increase the blood lipid peroxidation levels in the control group, confirming the induction of oxidative stress. An increase in blood lipid peroxidation was significantly inhibited by the consumption of concentrated H2 NanoGAS® (C-HN) water. Furthermore, the measurement of mitochondrial activity in the liver revealed that drinking H2 NanoGAS® water helped to maintain at a normal level and/or boosted the functional activity of the electron transport system in mitochondria affected by ethanol intake. To our knowledge, this study is the first to provide evidence for the use of orally ingested UFBs as carriers for the delivery gases to tissues, thereby exerting their physiological activity in the body. Our findings highlight the potential for the application of UFBs to various physiologically active gases and their utilization in the medical field in the future.


Assuntos
Etanol , Hidrogênio , Peroxidação de Lipídeos , Fígado , Estresse Oxidativo , Animais , Estresse Oxidativo/efeitos dos fármacos , Etanol/administração & dosagem , Hidrogênio/farmacologia , Hidrogênio/administração & dosagem , Masculino , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Administração Oral , Ratos , Ratos Wistar , Água , Antioxidantes/farmacologia , Antioxidantes/administração & dosagem
20.
Methods Mol Biol ; 2796: 1-21, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38856892

RESUMO

Cell membranes are highly intricate systems comprising numerous lipid species and membrane proteins, where channel proteins, lipid molecules, and lipid bilayers, as continuous elastic fabric, collectively engage in multi-modal interplays. Owing to the complexity of the native cell membrane, studying the elementary processes of channel-membrane interactions necessitates a bottom-up approach starting from forming simplified synthetic membranes. This is the rationale for establishing an in vitro membrane reconstitution system consisting of a lipid bilayer with a defined lipid composition and a channel molecule. Recent technological advancements have facilitated the development of asymmetric membranes, and the contact bubble bilayer (CBB) method allows single-channel current recordings under arbitrary lipid compositions in asymmetric bilayers. Here, we present an experimental protocol for the formation of asymmetric membranes using the CBB method. The KcsA potassium channel is a prototypical model channel with huge structural and functional information and thus serves as a reporter of membrane actions on the embedded channels. We demonstrate specific interactions of anionic lipids in the inner leaflet. Considering that the local lipid composition varies steadily in cell membranes, we `present a novel lipid perfusion technique that allows rapidly changing the lipid composition while monitoring the single-channel behavior. Finally, we demonstrate a leaflet perfusion method for modifying the composition of individual leaflets. These techniques with custom synthetic membranes allow for variable experiments, providing crucial insights into channel-membrane interplay in cell membranes.


Assuntos
Bicamadas Lipídicas , Canais de Potássio , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Canais de Potássio/química , Canais de Potássio/metabolismo , Membrana Celular/metabolismo , Membrana Celular/química , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo
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