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Food Chemistry Jun 2024We propose a co-immobilized chemo-enzyme cascade system to mitigate random intermediate diffusion from the mixture of individual immobilized catalysts and achieve a...
We propose a co-immobilized chemo-enzyme cascade system to mitigate random intermediate diffusion from the mixture of individual immobilized catalysts and achieve a one-pot reaction of multi-enzyme and reductant. Catalyzed by lipase and lipoxygenase, unsaturated lipid hydroperoxides (HPOs) were synthesized. 13(S)-hydroperoxy-9Z, 11E-octadecadienoic acid (13-HPODE), one compound of HPOs, was subsequently reduced to 13(S)-hydroxy-9Z, 11E-octadecadienoic acid (13-HODE) by cysteine. Upon the optimized conditions, 75.28 mg of 13-HPODE and 4.01 mg of 13-HODE were produced from per milliliter of oil. The co-immobilized catalysts exhibited improved yield compared to the mixture of individually immobilized catalysts. Moreover, it demonstrated satisfactory durability and recyclability, maintaining a relative HPOs yield of 78.5% after 5 cycles. This work has achieved the co-immobilization of lipase, lipoxygenase and the reductant cysteine for the first time, successfully applying it to the conversion of soybean oil into 13-HODE. It offers a technological platform for transforming various oils into high-value products.
PubMed: 38950510
DOI: 10.1016/j.foodchem.2024.140187 -
Talanta Jun 2024Tumor spheroids are widely studied for in vitro modeling of tumor growth and responses to anticancer drugs. However, current methods are mostly limited to static and...
Tumor spheroids are widely studied for in vitro modeling of tumor growth and responses to anticancer drugs. However, current methods are mostly limited to static and perfusion-based cultures, which can be improved by more accurately mimicking pathological conditions. Here, we developed a diffusion-based dynamic culture system for tumor spheroids studies using a thin membrane of hydrogel microwells and a microfluidic device. This allows for effective exchange of nutrients and metabolites between the tumors and the culture medium flowing underneath, resulting in uniform tumor spheroids. To monitor the growth and drug response of the spheroids in real-time, we performed spectroscopic analyses of the system's impedance, demonstrating a close correlation between the tumor size and the resistance and capacitance of the system. Our results also indicate an enhanced drug effect on the tumor spheroids in the presence of a low AC electric field, suggesting a weakening mechanism of the spheroids induced by external perturbation.
PubMed: 38950503
DOI: 10.1016/j.talanta.2024.126473 -
Journal of Colloid and Interface Science Jun 2024The diffusion and adsorption properties of the O/HO corpuscles at active sites play a crucial role in the fast photo-electrocatalytic reaction of hydrogen peroxide (HO)...
The diffusion and adsorption properties of the O/HO corpuscles at active sites play a crucial role in the fast photo-electrocatalytic reaction of hydrogen peroxide (HO) production. Herein, SnS nanosheets with abundant interfacial boundaries and large specific areas are encapsulated into hollow mesoporous carbon spheres (CSs) with flexibility, producing a yolk-shell SnS@CSs Z-scheme photocatalyst. The nanoconfined microenvironment of SnS@CSs could enrich O/HO in catalyst cavities, which allows sufficient internal O transfer, improving the surface chemistry of catalytic O to O conversion and increasing reaction kinetics. By shaping the mixture of SnS@CSs and polytetrafluoroethylene (PTFE) on carbon felt (CF) using the vacuum filtration method, the natural air-breathing gas diffusion photoelectrode (AGPE) was prepared, and it can achieve an accumulated concentration of HO about 12 mM after a 10 h stability test from pure water at natural pH without using electrolyte and sacrificial agents. The HO product is upgraded through one downstream route of conversion of HO to sodium perborate. The improved HO production performance could be ascribed to the combination of the confinement effect of SnS@CSs and the rich triple phase interfaces with the continuous hydrophobic layer and hydrophilic layer to synergistically modulate the photoelectron catalytic microenvironment, which enhanced the transfer of O mass and offered a stronger affinity to oxygen bubbles. The strategy of combining the confined material with the air-breathing gas diffusion electrode equips a wide practical range of applications for the synthesis of high-yield hydrogen peroxide.
PubMed: 38950469
DOI: 10.1016/j.jcis.2024.06.198 -
Journal of Colloid and Interface Science Jun 2024The energy storage capacity of porous carbon materials is closely tied to their surface structure and chemical properties. However, developing an innovative and...
The energy storage capacity of porous carbon materials is closely tied to their surface structure and chemical properties. However, developing an innovative and straightforward approach to synthesize yolk-shell carbon spheres (YCs) remains a great challenge till date. Herein, we prepared a series of porous nitrogen-doped yolk-shell carbon spheres (NYCs) via a "pyrolysis-capture" method. This method involves coating the resorcinol-formaldehyde (RF) resin sphere with a layer of compact silica shell induced by 2-methylimidazole (ME) catalysis to produce a confined nano-space. Based on the confined effect of compact silica shell, volatile gases emitted from the RF resin and ME during pyrolysis can not only diffuse into the pores of the RF resin but can also be captured to form an outer carbon shell. This results in the tunable structures of NYCs materials. As the pyrolysis temperature rises, the shell thickness of NYCs reduces, the pore size expands, the roughness increases, and the N/O content of surface elements is enhanced. Notably, as an electrode material used forsupercapacitors,the optimized NYCs-800 exhibits excellent performance with a capacitance of 301.2F g at the current density of 1 A/g and outstanding cycling life stability of 96.1% after 10,000 cycles. These results signify that controlling the surface structure and chemical properties of NYCs materials is an effective approach for constructing advanced energy storage materials.
PubMed: 38950467
DOI: 10.1016/j.jcis.2024.06.143 -
The Journal of Physical Chemistry... Jul 2024The bactericidal potency of ionic liquids (ILs) is well-established, yet their precise mechanism of action remains elusive. Here, we show evidence that the bactericidal...
The bactericidal potency of ionic liquids (ILs) is well-established, yet their precise mechanism of action remains elusive. Here, we show evidence that the bactericidal action of ILs primarily involves the permeabilization of the bacterial cell membrane. Our findings reveal that ILs exert their effects by directly interacting with the lipid bilayer and enhancing the membrane dynamics. Lateral lipid diffusion is accelerated, which in turn augments membrane permeability, ultimately leading to bacterial death. Furthermore, our results establish a significant connection: an increase in the alkyl chain length of ILs correlates with a notable enhancement in both lipid lateral diffusion and antimicrobial potency. This underscores a compelling correlation between membrane dynamics and antimicrobial effectiveness, providing valuable insights for the rational design and optimization of IL-based antimicrobial agents in healthcare applications.
PubMed: 38950375
DOI: 10.1021/acs.jpclett.4c01066 -
Proceedings of the National Academy of... Jul 2024While the intracellular-extracellular distribution of lactate has been suggested to play a critical role in the healthy and diseased brain, tools are lacking to...
While the intracellular-extracellular distribution of lactate has been suggested to play a critical role in the healthy and diseased brain, tools are lacking to noninvasively probe lactate in intracellular and extracellular spaces. Here, we show that, by measuring the diffusion of lactate with diffusion-weighted magnetic resonance (MR) spectroscopy in vivo and comparing it to the diffusion of purely intracellular metabolites, noninvasive quantification of extracellular and intracellular lactate fractions becomes possible. More specifically, we detect alterations of lactate diffusion in the APP/PS1 mouse model of Alzheimer's disease. Data modeling allows quantifying decreased extracellular lactate fraction in APP/PS1 mice as compared to controls, which is quantitatively confirmed with implanted enzyme-microelectrodes. The capability of diffusion-weighted MR spectroscopy to quantify extracellular-intracellular lactate fractions opens a window into brain metabolism, including in Alzheimer's disease.
Topics: Animals; Lactic Acid; Alzheimer Disease; Brain; Mice; Mice, Transgenic; Diffusion Magnetic Resonance Imaging; Extracellular Space; Disease Models, Animal; Magnetic Resonance Spectroscopy; Male; Amyloid beta-Protein Precursor
PubMed: 38950371
DOI: 10.1073/pnas.2403635121 -
Optics Letters Jul 2024While lasers have found their successful applications in various clinical specialties, in clinical dental practice, traditional mechanical drills are still predominantly...
While lasers have found their successful applications in various clinical specialties, in clinical dental practice, traditional mechanical drills are still predominantly utilized. Although erbium-doped lasers have been demonstrated for dental therapy, their clinical performance is still not satisfactory due to the long pulse width, low peak power, and small repetition rate. To attain a smaller thermal diffusion thus better biological safety and surgical precision, as well as more rapid ablation, the advancement of femtosecond laser techniques has opened another route of dental surgery; however, no biological safety investigation has been reported. Here, we present a systematic study of dental ablation by a Yb:CaAlGdO regenerative amplifier with a central wavelength of 1040 nm and pulse width of 160 fs. The in vivo experiment of dental surgery investigating the inflammatory response has been reported, for the first time to the best of our knowledge. It is demonstrated that dental surgery by Yb:CaAlGdO femtosecond laser ablation has better biological safety compared to the turbine drilling, thanks to its non-contact and ultrafast heat dissipation nature.
Topics: Laser Therapy; Animals; Ytterbium; Lasers, Solid-State
PubMed: 38950222
DOI: 10.1364/OL.525402 -
ACS Applied Materials & Interfaces Jul 2024Associative multimodal artificial intelligence (AMAI) has gained significant attention across various fields, yet its implementation poses challenges due to the burden...
Associative multimodal artificial intelligence (AMAI) has gained significant attention across various fields, yet its implementation poses challenges due to the burden on computing and memory resources. To address these challenges, researchers have paid increasing attention to neuromorphic devices based on novel materials and structures, which can implement classical conditioning behaviors with simplified circuitry. Herein, we introduce an artificial multimodal neuron device that shows not only the acquisition behavior but also the extinction and the spontaneous recovery behaviors for the first time. Being composed of an ovonic threshold switch (OTS)-based neuron device, a conductive bridge memristor (CBM)-based synapse device, and a few passive electrical elements, such observed behaviors of this neuron device are explained in terms of the electroforming and the diffusion of metallic ions in the CBM. We believe that the proposed associative learning neuron device will shed light on the way of developing large-scale AMAI systems by providing inspiration to devise an associative learning network with improved energy efficiency.
PubMed: 38950119
DOI: 10.1021/acsami.4c02343 -
Journal of Fish Diseases Jul 2024In this study, the "milky disease" model of Eriocheir sinhensis was constructed via intramuscular injection with the pathogenic yeast Metschnikowia bicuspidata. The...
In this study, the "milky disease" model of Eriocheir sinhensis was constructed via intramuscular injection with the pathogenic yeast Metschnikowia bicuspidata. The dynamic pathological changes of E. sinensis after injection were elucidated with two staining methods (haemotoxylin-eosin and alcian blue periodic acid-Schiff) and fluorescence in situ hybridization technology. Anatomical observation revealed three stages of the "milky disease": no clinical signs (1-4 days after infection), the appearance of signs of disease (5-7 days), and significant liquefaction (10 days). Histological observation also revealed three stages of the disease: yeast diffusion (1-2 days after infection), yeast slow development (3-4 days), and yeast rapid proliferation (5 days). And FISH technique was suitable for the early detection of infection with M. bicuspidata in E. sinensis. We found that M. bicuspidata spread to the whole body of the crab through the haemolymph and developed into fungal septicaemia. These results elucidate the systemic pathological characteristics of "milky disease" in E. sinensis and suggest the pathogenic mechanism of M. bicuspidata.
PubMed: 38950086
DOI: 10.1111/jfd.13993 -
PloS One 2024This study investigates the phenomena of semantic drift through the lenses of language and situated simulation (LASS) and the word frequency effect (WFE) within a timed...
This study investigates the phenomena of semantic drift through the lenses of language and situated simulation (LASS) and the word frequency effect (WFE) within a timed word association task. Our primary objectives were to determine whether semantic drift can be identified over the short time (25 seconds) of a free word association task (a predicted corollary of LASS), and whether more frequent terms are generated earlier in the process (as expected due to the WFE). Respondents were provided with five cue words (tree, dog, quality, plastic and love), and asked to write as many associations as they could. We hypothesized that terms generated later in the task (fourth time quartile, the last 19-25 seconds) would be semantically more distant (cosine similarity) from the cue word than those generated earlier (first quartile, the first 1-7 seconds), indicating semantic drift. Additionally, we explored the WFE by hypothesizing that earlier generated words would be more frequent and less diverse. Utilizing a dataset matched with GloVe 300B word embeddings, BERT and WordNet synsets, we analysed semantic distances among 1569 unique term pairs for all cue words across time. Our results supported the presence of semantic drift, with significant evidence of within-participant, semantic drift from the first to fourth time (LASS) and frequency (WFE) quartiles. In terms of the WFE, we observed a notable decrease in the diversity of terms generated earlier in the task, while more unique terms (greater diversity and relative uniqueness) were generated in the 4th time quartile, aligning with our hypothesis that more frequently used words dominate early stages of a word association task. We also found that the size of effects varied substantially across cues, suggesting that some cues might invoke stronger and more idiosyncratic situated simulations. Theoretically, our study contributes to the understanding of LASS and the WFE. It suggests that semantic drift might serve as a scalable indicator of the invocation of language versus simulation systems in LASS and might also be used to explore cognition within word association tasks more generally. The findings also add a temporal and relational dimension to the WFE. Practically, our research highlights the utility of word association tasks in understanding semantic drift and the diffusion of word usage over a sub-minute task, arguably the shortest practically feasible timeframe, offering a scalable method to explore group and individual changes in semantic relationships, whether via the targeted diffusion of influence in a marketing campaign, or seeking to understand differences in cognition more generally. Possible practical uses and opportunities for future research are discussed.
Topics: Semantics; Humans; Male; Language; Female; Adult; Cues; Young Adult
PubMed: 38950044
DOI: 10.1371/journal.pone.0305568