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1.
Neural Regen Res ; 20(1): 116-129, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38767481

RESUMEN

Acute ischemic stroke is a clinical emergency and a condition with high morbidity, mortality, and disability. Accurate predictive, diagnostic, and prognostic biomarkers and effective therapeutic targets for acute ischemic stroke remain undetermined. With innovations in high-throughput gene sequencing analysis, many aberrantly expressed non-coding RNAs (ncRNAs) in the brain and peripheral blood after acute ischemic stroke have been found in clinical samples and experimental models. Differentially expressed ncRNAs in the post-stroke brain were demonstrated to play vital roles in pathological processes, leading to neuroprotection or deterioration, thus ncRNAs can serve as therapeutic targets in acute ischemic stroke. Moreover, distinctly expressed ncRNAs in the peripheral blood can be used as biomarkers for acute ischemic stroke prediction, diagnosis, and prognosis. In particular, ncRNAs in peripheral immune cells were recently shown to be involved in the peripheral and brain immune response after acute ischemic stroke. In this review, we consolidate the latest progress of research into the roles of ncRNAs (microRNAs, long ncRNAs, and circular RNAs) in the pathological processes of acute ischemic stroke-induced brain damage, as well as the potential of these ncRNAs to act as biomarkers for acute ischemic stroke prediction, diagnosis, and prognosis. Findings from this review will provide novel ideas for the clinical application of ncRNAs in acute ischemic stroke.

2.
J Agric Food Chem ; 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39364925

RESUMEN

In this work, the paraffin oil was first molecularly distilled into two mineral oil saturated hydrocarbons (MOSH) subfractions with their main carbon number range of C20-30 (84.58%) and C30-50 (89.65%), which were determined using a liquid chromatography-gas chromatography-flame ionization detector (LC-GC-FID) technique. Then, both female and male Fischer 344 (F344) rats were fed with the diets containing one of these two MOSH subfractions at the low (1.5 g/kg) or high dose (15 g/kg) for 6 months. It was found that the exposure of MOSH C20-30 subfraction could result in a significant increase of spleen weight index (4.64 ± 0.18 mg/g for female and 3.79 ± 0.31 mg/g for male rats) (P < 0.05), and irregular shape of white medulla, and the macrophage infiltration in mesenteric lymph node for both female and male rats, especially for the 15 g/kg MOSH C20-30-fed rats. Meanwhile, both MOSH C20-30 and C30-50 subfraction promoted inflammation and oxidative stress and had a negative effect on the immune function in both female and male rats. The metabolomics results further supported these observations, and indicated the down-regulation of cysteine and methionine metabolism, and glutathione metabolism pathway in female and male rats, respectively.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39388324

RESUMEN

Event cameras are novel bio-inspired sensors, where individual pixels operate independently and asynchronously, generating intensity changes as events. Leveraging the microsecond resolution (no motion blur) and high dynamic range (compatible with extreme light conditions) of events, there is considerable promise in directly segmenting objects from sparse and asynchronous event streams in various applications. However, different from the rich cues in video object segmentation, it is challenging to segment complete objects from the sparse event stream. In this paper, we present the first framework for continuous-time object segmentation from event stream. Given the object mask at the initial time, our task aims to segment the complete object at any subsequent time in event streams. Specifically, our framework consists of a Recurrent Temporal Embedding Extraction (RTEE) module based on a novel ResLSTM, a Cross-time Spatiotemporal Feature Modeling (CSFM) module which is a transformer architecture with long-term and short-term matching modules, and a segmentation head. The historical events and masks (reference sets) are recurrently fed into our framework along with current-time events. The temporal embedding is updated as new events are input, enabling our framework to continuously process the event stream. To train and test our model, we construct both real-world and simulated event-based object segmentation datasets, each comprising event streams, APS images, and object annotations. Extensive experiments on our datasets demonstrate the effectiveness of the proposed recurrent architecture. Our code and dataset are available at https://sites.google.com/view/ecos-net/.

4.
Artículo en Inglés | MEDLINE | ID: mdl-39395024

RESUMEN

OBJECTIVE: Rab11A is an important molecule for recycling endosomes and is closely related to the proliferation, invasion, and metastasis of tumors. This study investigated the prognostic and immune significance of Rab11A and validated its potential function and mechanism in breast cancer (BRCA). METHODS: RNA sequencing data for 33 tumors were downloaded from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression databases. Correlation analysis was used to evaluate the relationship between Rab11A expression and immune characteristics. Potential pathways were identified using the Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analysis. Immunohistochemical analysis, colony formation assay, bromodeoxyuridine incorporation assay, immunofluorescence, and Western blot were used to explore potential function and mechanism. RESULTS: Analysis of the TCGA database showed significant upregulation of Rab11A expression in a variety of cancers. Rab11A was up-regulated in 82.4% of BRCA. High Rab11A expression is associated with poor survival in cancer patients and is a predictor of poor prognosis. CIBERSORT analysis showed that Rab11A was negatively associated with almost all immune cycle activity scores pan-cancer. The results of the TCGA-BRCA cohort were further confirmed by using pathological samples from clinical BRCA patients. The results showed that Rab11A expression was correlated with estrogen receptor (ER) and progesterone receptor expression in BRCA (p < 0.05). Knockdown and overexpression of Rab11A affected the proliferation of BRCA cells. Further mechanistic studies revealed that down-regulation of ER alpha (ERα) and up-regulation of ER beta (ERß) mediated Rab11A-induced inhibition of BRCA cell proliferation. CONCLUSION: Rab11A expression in pan-cancer is associated with poor prognosis and immune profile. In particular, in BRCA, Rab11A expression regulates cell proliferation by targeting ERα and ERß. High Rab11A expression is tightly associated with immune characteristics, tumor microenvironment, and genetic mutations. These results provide a reference for exploring the role of Rab11A in pan-cancer and provide a new perspective for revealing potential therapeutic targets in BRCA.

5.
Angew Chem Int Ed Engl ; : e202418420, 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39401092

RESUMEN

MXene (Ti3C2Tx) is renowned for its exceptional conductivity and hydrophilicity; however, the low yield of monolayers hinders its industrial scalability. Herein, we present a strategy to substantially enhance the monolayer yield by disrupting the hydrogen-bonding cage confinement of multilayer MXene using high-temperature ultrasound, challenging the conventional belief that monolayer MXene can only be prepared at lower temperatures. At approximately 70 °C, the weakened hydrogen bonding between the oxygen-containing terminal groups of multilayer MXene and surrounding water molecules weakens the hydrogen-bond cage confinement. This enables ultrasonic cavitation to generate more microbubbles that penetrate the interlayers of multilayer MXene, resulting in gentle and thorough delamination into larger monolayer nanosheets. Achieving up to a 95% yield in just tens of minutes, these nanosheets exhibit properties comparable to those produced by traditional ice-bath methods. Furthermore, the high-concentration MXene ink produced on a large scale using this high-yield approach exhibits excellent printing and processing capabilities, and the corresponding products showcase superior infrared stealth and Joule heating characteristics. This work addresses a key technical bottleneck in MXene production, paving the way for its extensive technological and industrial applications.

6.
Front Immunol ; 15: 1459241, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39421753

RESUMEN

Introduction: Systemic lupus erythematosus (SLE) is a complex autoimmune disease, and despite the availability of multiple treatments, striking a balance between long-term efficacy and side effects remains a major clinical challenge. B-cell-directed therapy has attracted much attention because of its unique mechanism of action. Belimumab and obinutuzumab, as representative drugs for B-cell-directed therapy, have shown their respective advantages for SLE treatment. However, data on combination therapy with obinutuzumab and belimumab are currently unavailable. Case presentation: We present the severe case report of a patient who was diagnosed with lupus nephritis (LN) with gastrointestinal involvement and developed acute renal failure. The patient responded to the first dose of obinutuzumab but failed to achieve a complete response to LN. The repeated use of obinutuzumab was limited by persistently low IgG levels and frequent infections. This is a real-world challenge that must be addressed. Therefore, the patient was subsequently treated with a novel sequential regimen of obinutuzumab followed by belimumab. After 18 months of follow-up, the patient achieved a complete clinical response with a favourable safety profile, along with the conversion of all autoantibodies from positive to negative and sustained negativity. To date, the patient has achieved a dual clinical and serological response. Conclusion: There is a reason to believe that this novel combination regimen could be developed as a therapeutic strategy, with the expectation of balancing efficacy and safety.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Inmunosupresores , Lupus Eritematoso Sistémico , Humanos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/complicaciones , Inmunosupresores/uso terapéutico , Inmunosupresores/administración & dosificación , Femenino , Resultado del Tratamiento , Adulto , Nefritis Lúpica/tratamiento farmacológico , Estudios de Seguimiento , Quimioterapia Combinada
7.
Obes Facts ; : 1-28, 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39413746

RESUMEN

BACKGROUND: This systematic scoping review aims to synthesize research findings on the clinical manifestations in patients with non-alcoholic fatty liver disease (NAFLD) and sarcopenia, focusing on studies published between December 2013 and December 2023. SUMMARY: We conducted a comprehensive systematic scoping review of five databases and identified 312 articles, with 9 studies included in the final review. Most were cross-sectional investigations, and 70% were from Asian cohorts. A comparative analysis revealed that patients with both NAFLD and sarcopenia tended to be older, had a higher body mass index, and a higher prevalence among females. These findings emphasize the role of unhealthy lifestyles and obesity. Common comorbidities included metabolic syndrome, hypertension, and diabetes. However, the lack of standardized diagnostic criteria poses a significant challenge in accurately identifying this patient subgroup. KEY MESSAGES: This review highlights distinct clinical characteristics in NAFLD patients with sarcopenia, such as older age, higher body mass index, and a higher prevalence in females. Comorbidities also play a significant role. However, the lack of comprehensive studies limits early detection and intervention. Future research should address these gaps by developing standardized diagnostic criteria and effective management strategies for this patient group.

8.
Materials (Basel) ; 17(19)2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39410478

RESUMEN

In this study, we optimized the traditional composition of AISI 8630 steel and evaluated its corrosion resistance through a series of tests. We conducted corrosion tests in a 3.5% NaCl solution and performed a 720 h fixed-load tensile test in accordance with the NACE TM-0177-2016 standard to assess sulfide stress corrosion cracking (SSCC). To analyze the corrosion products and the structure of the corrosion film, we employed X-ray diffraction and transmission electron microscopy. The corrosion rate, characteristics of the corrosion products, structure of the corrosion film, and corrosion resistance mechanism of the material were investigated. The results indicate that the optimized AISI 8630 material demonstrates excellent corrosion resistance. After 720 h of exposure, the primary corrosion products were identified as chromium oxide, copper sulfide, iron oxide, and iron-nickel sulfide. The corrosion film exhibited a three-layer structure: the innermost layer with a thickness of 200-300 nm contained higher concentrations of alloying elements and formed a dense, cohesive rust layer that hindered the diffusion of oxygen and chloride ions, thus enhancing corrosion resistance. The middle layer was thicker and less rich in alloying elements, while the outer layer, approximately 300-400 nm thick, was relatively loose.

9.
EJNMMI Radiopharm Chem ; 9(1): 71, 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39412702

RESUMEN

BACKGROUND: In the central nervous system, type 2 vesicular monoamine transporters (VMAT2) are responsible for the reuptake of monoamines from synaptic junction back to pre-synaptic terminal vesicles. These transporters are functionally crucial as they reflect the integrity of monoamine neurons. D6-[18F]FP-(+)-DTBZ, a novel deuterated VMAT2 radioligand, has shown promise as a potential PET tracer for the diagnosis of Parkinson's disease (PD). This study evaluates the biodistribution and dosimetry of D6-[18F]FP-(+)-DTBZ and includes a head-to-head comparison with its non-deuterated version, [18F]FP-(+)-DTBZ (AV-133), in healthy individuals and PD patients. RESULTS: The automated synthesis of D6-[18F]FP-(+)-DTBZ using the SPE method was accomplished in 35 min, yielding a high radiochemical purity (> 99%) and high radiochemical yields (35 ± 5%). The biodistribution and dosimetry study indicated an effective dose of 37.1 ± 7.2 µSv/MBq, with the liver receiving the highest radiation dose (289.6 ± 42.1 µGy/MBq), followed by pancreas (185.2 ± 29.1 µGy/MBq). Brain imaging with D6-[18F]FP-(+)-DTBZ exhibited a significantly increased uptake in VMAT2-rich regions, particularly the striatum. In a head-to-head comparison between [18F]FP-(+)-DTBZ and D6-[18F]FP-(+)-DTBZ, the latter exhibited approximately 15% higher SUVR in the caudate, putamen, and nucleus accumbens. Preliminary studies in PD patients showed a substantial reduction in VMAT2 uptake in the striatum, with the most pronounced decrease observed in the putamen (a 53% decline). CONCLUSIONS: D6-[18F]FP-(+)-DTBZ is a safe and improved VMAT2-specific imaging agent, which may be suitable for diagnosing PD by evaluating changes in VMAT2 binding of monoamine neurons in the brain. Trial registration Chinese Clinical Trial Registry, ChiCTR2200057218, Registered 16 August 2021, https://www.chictr.org.cn/bin/project/edit?pid=142725 .

10.
Front Pharmacol ; 15: 1456721, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39415839

RESUMEN

Purpose: Rhubarb (Rheum palmatum L.) and astragalus (Radix astragali) find widespread used in clinical formulations for treating chronic kidney disease (CKD). Notably, the key active components, total rhubarb anthraquinone (TRA) and total astragalus saponin (TAS), exhibit superiority over rhubarb and astragalus in terms of their clear composition, stability, quality control, small dosage, and efficacy for disease treatment. Additionally, astragalus polysaccharides (APS) significantly contribute to the treatment of renal fibrosis by modulating the gut microbiota. However, due to differences in the biopharmaceutical properties of these components, achieving synergistic effects remains challenging. This study aims to develop combined pellets (CPs) and evaluate the potential effect on unilateral ureteral obstruction (UUO)-induced renal fibrosis. Methods: The CPs pellets were obtained by combining TRA/TAS-loaded SNEDDS pellets and APS-loaded pellets, prepared using the fluidized bed coating process. The prepared pellets underwent evaluation for morphology, bulk density, hardness, and flowing property. Moreover, the in vitro release of the payloads was evaluated with the CHP Type I method. Furthermore, the unilateral ureteral obstruction (UUO) model was utilized to investigate the potential effects of CPs pellets on renal fibrosis and their contribution to gut microbiota modulation. Results: The ex-vivo study demonstrated that the developed CPs pellets not only improved the dissolution of TRA and TAS but also delivered TRA/TAS and APS spatiotemporally to the appropriate site along the gastrointestinal tract. In an animal model of renal fibrosis (UUO rats), oral administration of the CPs ameliorated kidney histological pathology, reduced collagen deposition, and decreased the levels of inflammatory cytokines. The CPs also restored the disturbed gut microbiota induced by UUO surgery and protected the intestinal barrier. Conclusion: The developed CPs pellets represent a promising strategy for efficiently delivering active components in traditional Chinese medicine formulas, offering an effective approach for treating CKD.

11.
RSC Adv ; 14(44): 32661-32667, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39416375

RESUMEN

Chlorine (Cl2) is highly toxic and pungent, and can cause irreversible harm to humans even at low concentrations. Therefore, it is significant to develop a sensor that is highly sensitive to trace amounts of Cl2 leakage. In this work, inexpensive peanut shells are used as a biological template to prepare K-doped indium oxide (K-In2O3) porous sheets through a simple three-step process. The characterization results reveal the porous sheet microstructure of the prepared K-In2O3 derived from the peanut shell bio-template, and the obtained material possesses rich oxygen vacancies and a high specific surface area. Gas-sensing tests demonstrate that the K-In2O3 porous sheet sensor exhibits excellent sensitivity to low concentrations of Cl2.

13.
Artículo en Inglés | MEDLINE | ID: mdl-39419848

RESUMEN

PURPOSE: Bisphosphonates are pivotal in managing bone tumors by inhibiting bone resorption. This study investigates the therapeutic potential of [177Lu]Lu-P15-073, a novel bisphosphonate, for radioligand therapy (RLT) in bone metastases. METHODS: Ten patients (age 35 to 75) with confirmed bone metastases underwent therapy with a single dose of [177Lu]Lu-P15-073 (1,225 ± 84 MBq, or 33 ± 2 mCi). Prior to treatment, bone metastases were verified via [99mTc]Tc-MDP bone scans. Serial planar whole-body scans monitored biodistribution over a 14-day period. Dosimetry was assessed for major organs and tumor lesions, while safety was evaluated through blood biomarkers and pain scores. RESULTS: Serial planar whole-body scans demonstrated rapid and substantial accumulation of [177Lu]Lu-P15-073 in bone metastases, with minimal uptake in blood and other organs. The absorbed dose in the critical organ, red marrow, was measured at (0.034 ± 0.010 mSv/MBq), with a notably low normalized effective dose (0.013 ± 0.005 mSv/MBq) compared to other 177Lu-labeled bisphosphonates. Persistent high uptake in bone metastases was observed, resulting in elevated tumor doses (median 3.12 Gy/GBq). Patients exhibited favorable tolerance to [177Lu]Lu-P15-073 therapy, with no new instances of side effects. Additionally, 87.5% (7/8) of patients experienced a significant reduction in pain scale (numerical rating scale, NRS, from 5.1 ± 2.3 to 3.0 ± 1.8). The tumor-background ratio (TBRmean) of [99mTc]Tc-MDP correlated significantly with [177Lu]Lu-P15-073 uptake (P < 0.01), indicating its potential for prediction of absorbed dose. CONCLUSIONS: This study demonstrates the safety, dosimetry, and efficacy of a single therapeutic dose of [177Lu]Lu-P15-073 in bone metastases. The treatment was well-tolerated with no severe adverse events. These findings suggest that [177Lu]Lu-P15-073 holds promise as a novel RLT agent for bone metastases.

14.
Natl Sci Rev ; 11(11): nwae247, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39440264

RESUMEN

Edge detection is a fundamental operation for feature extraction in image processing. The all-optical method has aroused growing interest owing to its ultra-fast speed, low energy consumption and parallel computation. However, current optical edge detection methods are generally limited to static devices and fixed functionality. Herein, we propose a fast-switchable scheme based on a ferroelectric liquid crystal topological structure. The self-assembled chiral lamellar superstructure, directed by the azimuthally variant photo-alignment agent, can be dynamically controlled by the polarity of the external electric field and respectively generates the vector beams with nearly orthogonal polarization distribution. Even after thousands of cycles, the horizontal and vertical edges of the object are selectively enhanced with an ultra-fast switching time of ∼57 µs. Broadband edge-enhanced imaging is efficiently demonstrated. This work extends the ingenious building of topological heliconical superstructures and offers an important glimpse into their potential in the emerging frontiers of optical computing for artificial intelligence.

15.
J Hazard Mater ; 480: 136242, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39442296

RESUMEN

The toxic effects of potentially toxic elements have been observed at low concentrations; however, many studies have focused on single-species toxicity testing. Consequently, it is imperative to quantify toxicity at the community level at environmental concentrations. A microcosm approach was employed in conjunction with the Lotka-Volterra model to ascertain the impact of environmentally relevant concentrations of cadmium (Cd) on plankton abundance, community function, and stability. The results demonstrated that Cd led to a reduction in the abundance of Daphnia magna, yet unexpectedly resulted in an increase in the abundance of Brachionus calyciflorus and Paramecium caudatum. Additionally, Cd was observed to impede primary productivity, metabolic capacity and the stability of the planktonic community. Further model analyses revealed that the environmental concentration of Cd directly reduced intrinsic growth rates and intraspecific interactions. In particular, we found that the predation effects of Daphnia magna on Brachionus calyciflorus were significantly weakened. The findings of this study offer quantitative evidence that Cd exposure exerts an indirect influence on the structure and functioning of plankton ecosystems, mediated by alterations in trophic interactions. The findings indicate that the impact of environmental concentrations of potentially toxic elements may be underestimated in single-species experiments.

16.
J Agric Food Chem ; 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39361353

RESUMEN

The global prevalence of type 2 diabetes mellitus has become a major public health challenge. Dietary intervention is a cornerstone of diabetes management, yet the optimal macronutrient composition remains an open question. In this study, mice were fed a western (W) diet, a moderately high-fat (MHF) diet, a high-protein-high-carbohydrate (HPHC) diet, or a high-protein-low-carbohydrate (HPLC) diet for 22 weeks to compare the effects of different dietary patterns on glucose homeostasis. Our results showed that a MHF diet, under consistent nutrient quality, was most beneficial for glucose metabolism. The MHF diet reduced two key inducers of diabetes─lipid accumulation and inflammation. Downregulation of intestinal CD36 induced by loss of Desulfovibrio colonization restrained lipid absorption and lipopolysaccharide (LPS) transport, which played a crucial role in MHF-mediated resistance to lipid accumulation and inflammation. The findings endorse a dietary pattern featuring MHF of appropriate nutrient quality as an effective strategy for diabetes management.

17.
J Biomed Mater Res A ; 2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-39429059

RESUMEN

Three-dimensional (3D) in vitro models enable us to understand cell behavior that is a better reflection of what occurs in vivo than 2D in vitro models. As a result, developing 3D models for extracellular matrix (ECM) has been growing exponentially. Most of the efforts for these 3D models are geared toward understanding cancer cells. An intricate network of cells that engages with cancer cells and can kill them are the immune cells, particularly cytotoxic T lymphocytes (CTLs). However, limited reports are available for 3D ECM mimics to understand CTL dynamics. Currently, we lack ECM mimetic hydrogels for immune cells, with sufficient control over variables, such as stiffness, to fully understand CTL dynamics in vitro. Here, we developed PEG-based hydrogels as ECM mimics for CTLs. The ECM mimics are targeted to mimic the stiffness of soft tissues where CTLs reside, migrate, and deliver their function. To understand cell-material interaction, we determined the porosity, biocompatibility, and stiffness of the ECM mimics. The ECM mimics have median pore sizes of 10.7 and 13.3 µm, close to the average nucleus size of CTLs (~8.6 µm), and good biocompatibility to facilitate cell migration. The stiffness of the ECM mimics corresponds to biologically relevant microenvironments such as lungs and kidneys. Using time-lapse fluorescence microscopy, 3D cell migration was imaged and measured. CTLs migrated faster in softer ECM mimic with larger pores, consistent with previous studies in collagen (the gold standard ECM mimic for CTLs). The work herein demonstrates that the PEG-based ECM mimic can serve as an in vitro tool to elucidate the cell dynamics of CTLs. Thus, this study opens possibilities to study the mechanics of CTLs in well-defined ECM mimic conditions in vitro.

18.
Nano Lett ; 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39373290

RESUMEN

A common issue with supported metal catalysts is the sintering of metal nanoparticles, resulting in catalyst deactivation. In this study, we propose a theoretical framework for realizing a real-time simulation of the reactivity of supported metal nanoparticles during the sintering process, combining density functional theory calculations, microkinetic modeling, Wulff-Kaichew construction, and sintering kinetic simulations. To validate our approach, we demonstrate its feasibility on α-Al2O3(0001)-supported Ag nanoparticles, where the simulated sintering behavior and ethylene epoxidation reaction rate as a function of time show qualitative agreement with experimental observation. Our proposed theoretical approach can be employed to screen out the promising microstructure feature of α-Al2O3 for stable supported Ag NPs, including the surface orientation and promoter species modified on it. The outlined approach of this work may be applied to a range of different thermocatalytic reactions other than ethylene epoxidation and provide guidance for the development of supported metal catalysts with long-term stability.

19.
Nanomaterials (Basel) ; 14(19)2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39404317

RESUMEN

Foam drainage agents enhance gas production by removing wellbore liquids. However, due to the ultra-high salinity environments of the Hechuan gas field (salinity up to 32.5 × 104 mg/L), no foam drainage agent is suitable for this gas field. To address this challenge, we developed a novel nanocomposite foam drainage system composed of quaternary ammonium and two types of nanoparticles. This work describes the design and synthesis of a quaternary ammonium foam drainage agent and nano-engineered stabilizers. Nonylphenol polyoxyethylene ether sulfosuccinate quaternary ammonium foam drainage agent was synthesized using maleic anhydride, sodium chloroacetate, N,N-dimethylpropylenediamine, etc., as precursors. We employed the Stöber method to create hydrophobic silica nanoparticles. Carbon quantum dots were then prepared and functionalized with dodecylamine. Finally, carbon quantum dots were incorporated into the mesopores of silica nanoparticles to enhance stability. Through optimization, the best performance was achieved with a (quaternary ammonium foam drainage agents)-(carbon quantum dots/silica nanoparticles) ratio of 5:1 and a total dosage of 1.1%. Under harsh conditions (salinity 35 × 104 mg/L, condensate oil 250 cm3/m3, temperature 80 °C), the system exhibited excellent stability with an initial foam height of 160 mm, remaining at 110 mm after 5 min. Additionally, it displayed good liquid-carrying capacity (160 mL), low surface tension (27.91 mN/m), and a long half-life (659 s). These results suggest the effectiveness of nanoparticle-enhanced foam drainage systems in overcoming high-salinity challenges. Previous foam drainage agents typically exhibited a salinity resistance of no more than 25 × 104 mg/L. In contrast, this innovative system demonstrates a superior salinity tolerance of up to 35 × 104 mg/L, addressing a significant gap in available agents for high-salinity gas fields. This paves the way for future development of advanced foam systems for gas well applications with high salinity.

20.
Foods ; 13(20)2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-39456403

RESUMEN

Lactic acid bacteria fermentation is a beneficial bioprocessing method that can improve the flavor, transform nutrients, and maintain the biological activity of foods. The aim of this study is to investigate the effects of Lactiplantibacillus plantarum dy-1 fermentation on the nutritional components, flavor and taste properties, and composition of saponin compounds and their hypolipidemic and antioxidant activities. The results suggested that the total polyphenol content increased, and the soluble polysaccharides and total saponin contents decreased in fermented bitter melon juice (FJ) compared with those in non-fermented bitter melon juice (NFJ). The determination of volatile flavor substances by GC-MS revealed that the response values of acetic acid, n-octanol, sedumol, etc., augmented significantly, and taste analysis with an electronic tongue demonstrated lower bitterness and higher acidity in FJ. Furthermore, UPLC-Q-TOF-MS/MS testing showed a significant decrease in bitter compounds, including momordicines I and II, and a significant increase in the active saponin momordicine U in the fermented bitter melon saponin group (FJBMS). The in vitro assays indicated that FJBMS exhibited similar antioxidant activities as the non-fermented bitter melon saponin group (NFBMS). The in vitro results show that both NFBMS and FJBMS, when used at 50 µg/mL, could significantly reduce fat accumulation and the malondialdehyde (MDA) content and increased the catalase (CAT) activity, while there was no significant difference in the bioactivities of NFBMS and FJBMS. In conclusion, Lactiplantibacillus plantarum dy-1 fermentation is an effective means to lower the bitterness value of bitter melon and preserve the well-known bioactivities of its raw materials, which can improve the edibility of bitter melon.

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