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1.
J Genet Genomics ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39293510

RESUMEN

Over the past decade, nanopore sequencing has experienced significant advancements and changes, transitioning from an initially emerging technology to a significant instrument in the field of genomic sequencing. However, as advancements in next-generation sequencing technology persist, nanopore sequencing also improves. This paper reviews the developments, applications, and outlook on nanopore sequencing technology. Currently, nanopore sequencing supports both DNA and RNA sequencing, making it widely applicable in areas such as telomere-to-telomere (T2T) genome assembly, direct RNA sequencing (DRS), and metagenomics. The openness and versatility of nanopore sequencing have established it as a preferred option for an increasing number of research teams, signaling a transformative influence on life science research. As nanopore sequencing technology advances, it provides a faster, more cost-effective approach with extended read lengths, demonstrating the significant potential for complex genome assembly, pathogen detection, environmental monitoring, and human disease research, offering a fresh perspective in sequencing technologies.

2.
Phytochem Anal ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39233523

RESUMEN

INTRODUCTION: Insight into comparing key active ingredients of Radix Bupleuri (RB) based on different processing technologies is a key step to reveal the material basis of drug efficacy and a challenging task for developing traditional Chinese medicine (TCM). OBJECTIVE: This work aims to establish a comprehensive comparative analysis method of TCM and its processed products, which can be used to analyze the changing trend of active components of RB before and after processing. METHODS: First, RB was processed with rice vinegar, rice wine, and honey. Then, ultra-high-performance liquid chromatography (UHPLC) and gas chromatography (GC) coupled with mass spectrometry (MS) technology as well as multiple statistical analyses were used to comprehensively evaluate the compositional variation of polar and volatile compounds in RB under different processing processes. Meanwhile, in UHPLC-MS, a sequential window acquisition of all theoretical fragment ion spectral and information-dependent acquisition mutual authentication (SIMA) was developed. RESULTS: A total of 30 polar components and 33 volatile components were identified as chemical markers (mainly type II saikosaponins, terpenes, and fatty acid esters). These may be the material basis for giving unique pharmacological activities to RB and its processed products. CONCLUSIONS: These findings provided a solid foundation for the differentiated clinical application of RB, and the SIMA method held great potential for achieving accurate analysis of TCM processing ingredients.

3.
Ying Yong Sheng Tai Xue Bao ; 35(6): 1681-1688, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-39235027

RESUMEN

Rhizosphere is a vital area for substance exchange and energy transfer between roots and soil microorganisms. Therefore, diazotrophs in the rhizosphere play a pivotal role in facilitating plant nitrogen acquisition. We investigated the variability in the abundance and community structure of soil diazotrophs and the influencing factors across rhizosphere soils of Cunninghamia lanceolata in three locations: Baisha State-owned Forest Farm in Longyan City (BS), Sanming Forest Ecosystem and Global Change Research Station (SM), and Wuyishan National Forest Park in Nanping City (WYS), located in the western region of Fujian Province, quantified the diazotrophic abundance by using real-time quantitative PCR, and assessed the community structure by high-throughput sequencing. The results showed that soil pH, C:N ratio, and C:(N:P) stoichiometry in SM were notably lower compared to those in BS and WYS. In SM, the abundance of the nifH gene was 6.38×108 copies·g-1, significantly lower than 1.35×109 copies·g-1 in BS and 1.10×109 copies·g-1 in WYS. Additionally, α diversity index of diazotrophs was lower in SM compared to BS and WYS, while the community structure of diazotrophs in rhizosphere soils of BS and WYS was similar, which differed significantly from that in SM. The diazotrophic sequences in the three forest farms could be divided into 5 phylum, 8 classes, 15 orders, 23 families and 33 genera, with Proteobacteria, α-proteobacteria, and Bradyrhizobium as the dominant phylotypes. Soil pH, available phosphorus, NO3--N and C:(N:P) ratio were identified as significant factors influencing both the abundance and community structure of nifH genes, with soil pH performing the greatest. Taken together, there were spatial variations in the distribution of diazotrophic abundance and community structure in C. lanceolata rhizosphere soils, with soil pH as the primary driving factor.


Asunto(s)
Cunninghamia , Rizosfera , Microbiología del Suelo , Cunninghamia/crecimiento & desarrollo , China , Suelo/química , Nitrógeno/análisis , Nitrógeno/metabolismo , Fijación del Nitrógeno , Bacterias Fijadoras de Nitrógeno/metabolismo , Bacterias Fijadoras de Nitrógeno/clasificación , Bacterias Fijadoras de Nitrógeno/aislamiento & purificación , Bacterias Fijadoras de Nitrógeno/genética , Clima Tropical
4.
Food Chem ; 463(Pt 2): 141221, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39276555

RESUMEN

Allergy to novel food proteins, due to diverse ingredients and innovative food processing technologies employed to achieve desired functional properties, is a major safety concern. Current allergy testing methods (ELISA and mass spectrometry) depend on high-quality protein extracts, meaning existing methods are often tailored to specific matrices. Therefore, a more efficient and general protein extraction method is desirable for comprehensive allergy risk assessment. Here, we developed a highly efficient and reproducible protein extraction method which achieved at least 80 % efficiency across several food matrices. Proteomics analysis of a plant-based meat using our optimized extraction method showed that higher extraction efficiency improved reproducibility of identified proteins. Moreover, higher protein extraction efficiency resulted in increased abundances of individual allergenic proteins. This underscores the relevance of our method for more accurate measurements of allergenic protein concentrations in allergy risk assessments.

5.
Theranostics ; 14(12): 4622-4642, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39239516

RESUMEN

Rationale: Consumption of a high-fat diet (HFD) has been implicated in cognitive deficits and gastrointestinal dysfunction in humans, with the gut microbiota emerging as a pivotal mediator of these diet-associated pathologies. The introduction of plant-based polysaccharides into the diet as a therapeutic strategy to alleviate such conditions is gaining attention. Nevertheless, the mechanistic paradigm by which polysaccharides modulate the gut microbiota remains largely undefined. This study investigated the mechanisms of action of Eucommiae cortex polysaccharides (EPs) in mitigating gut dysbiosis and examined their contribution to rectifying diet-related cognitive decline. Methods: Initially, we employed fecal microbiota transplantation (FMT) and gut microbiota depletion to verify the causative role of changes in the gut microbiota induced by HFD in synapse engulfment-dependent cognitive impairments. Subsequently, colonization of the gut of chow-fed mice with Escherichia coli (E. coli) from HFD mice confirmed that inhibition of Proteobacteria by EPs was a necessary prerequisite for alleviating HFD-induced cognitive impairments. Finally, supplementation of HFD mice with butyrate and treatment of EPs mice with GW9662 demonstrated that EPs inhibited the expansion of Proteobacteria in the colon of HFD mice by reshaping the interactions between the gut microbiota and colonocytes. Results: Findings from FMT and antibiotic treatments demonstrated that HFD-induced cognitive impairments pertaining to neuronal spine loss were contingent on gut microbial composition. Association analysis revealed strong associations between bacterial taxa belonging to the phylum Proteobacteria and cognitive performance in mice. Further, introducing E. coli from HFD-fed mice into standard diet-fed mice underscored the integral role of Proteobacteria proliferation in triggering excessive synaptic engulfment-related cognitive deficits in HFD mice. Crucially, EPs effectively counteracted the bloom of Proteobacteria and subsequent neuroinflammatory responses mediated by microglia, essential for cognitive improvement in HFD-fed mice. Mechanistic insights revealed that EPs promoted the production of bacteria-derived butyrate, thereby ameliorating HFD-induced colonic mitochondrial dysfunction and reshaping colonocyte metabolism. This adjustment curtailed the availability of growth substrates for facultative anaerobes, which in turn limited the uncontrolled expansion of Proteobacteria. Conclusions: Our study elucidates that colonocyte metabolic disturbances, which promote Proteobacteria overgrowth, are a likely cause of HFD-induced cognitive deficits. Furthermore, dietary supplementation with EPs can rectify behavioral dysfunctions associated with HFD by modifying gut microbiota-colonocyte interactions. These insights contribute to the broader understanding of the modulatory effects of plant prebiotics on the microbiota-gut-brain axis and suggest a potential therapeutic avenue for diet-associated cognitive dysfunction.


Asunto(s)
Disfunción Cognitiva , Dieta Alta en Grasa , Disbiosis , Trasplante de Microbiota Fecal , Microbioma Gastrointestinal , Ratones Endogámicos C57BL , Polisacáridos , Microbioma Gastrointestinal/efectos de los fármacos , Animales , Dieta Alta en Grasa/efectos adversos , Ratones , Disfunción Cognitiva/terapia , Polisacáridos/farmacología , Masculino , Disbiosis/terapia , Colon/microbiología , Escherichia coli , Butiratos/metabolismo , Proteobacteria/aislamiento & purificación , Proteobacteria/efectos de los fármacos , Modelos Animales de Enfermedad
6.
Carbohydr Polym ; 346: 122644, 2024 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-39245531

RESUMEN

A complex heteropolysaccharide SCP-2 named schisanan B (Mw = 1.005 × 105 g/mol) was obtained from water extracts of Schisandra chinensis fruits, and its planar structure was finally deduced as a galacturonoglucan by a combination of monosaccharide compositions, methylation analysis, partial acid hydrolysis, enzymatic hydrolysis and 1D/2D-nuclear magnetic resonance spectroscopy. The conformation of SCP-2 exhibited a globular shape with branching in ammonium formate aqueous solutions. The rheological properties of SCP-2 were investigated on concentrations, temperature, pH and salts. The in vitro immunomodulatory activity assay demonstrated that SCP-2 significantly enhanced the production of nitric oxide (NO) and stimulated the secretion of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in macrophages. Through a combination of high-resolution live-cell imaging, surface plasmon resonance, and molecular docking techniques, SCP-2 exhibited a strong binding affinity with the Toll-like receptor 4 (TLR4). Moreover, western blot analysis revealed that SCP-2 effectively induced downstream signaling proteins associated with TLR4 activation, thereby promoting macrophage activation. The evidence strongly indicates that TLR4 functions as a membrane protein target in the activation of macrophages and immune regulation induced by SCP-2.


Asunto(s)
Frutas , Reología , Schisandra , Receptor Toll-Like 4 , Schisandra/química , Ratones , Frutas/química , Células RAW 264.7 , Animales , Receptor Toll-Like 4/metabolismo , Simulación del Acoplamiento Molecular , Óxido Nítrico/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Pectinas/química , Factor de Necrosis Tumoral alfa/metabolismo , Glucanos/química , Interleucina-6/metabolismo
7.
J Org Chem ; 89(17): 12508-12513, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39135492

RESUMEN

Thioesters make up an important class of bioactive compounds. Due to their chemoselectivity, they have been widely used in the synthesis of a wide range of complex bioactive molecules and natural products. At present, chemists have developed a variety of methods for the preparation of thioester compounds. However, these methods usually require the use of transition metal catalysis or harsh reaction conditions. The strategy of synthesizing thioester compounds via visible light-induced electron donor-acceptor (EDA) complex reactions avoids the problems associated with conventional methods through the development of photocatalysis. Here we report a sustainable method for thiocarbonylating aryl sulfonium salts via a visible light-induced EDA complex process without transition metals.

8.
Imeta ; 3(4): e210, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39135693

RESUMEN

Within dynamic agroecosystems, microbes can act as key intermediaries, facilitating spatiotemporal communication among plants. Future research could categorize key plant genes involved in plant-microbe interactions into microbiome-shaping genes (Ms genes) and microbiome-responsive genes (Mr genes), potentially leading to the construction of spatiotemporal molecular networks with microbes as intermediaries.

9.
Ann Hematol ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39129028

RESUMEN

Bariatric surgery is increasingly performed to treat severe obesity. As a result of anatomical and physiological changes in the gastrointestinal tract, the pharmacokinetics (PK) of oral drugs can be altered, affecting their efficacy and safety. This includes the class of tyrosine kinase inhibitors (TKIs) which are used to treat chronic myeloid leukemia (CML). This case series describes the clinical course of four CML cases with a history of bariatric surgery. The patients used various TKIs (nilotinib, dasatinib, bosutinib, ponatinib, and imatinib) for which 15 drug levels were measured. The measured TKI concentrations were in part subtherapeutic, and highly variable when compared to mean levels measured in the general population. Multiple drug levels were measured in these patients, as the clinicians were aware of the possible impact of bariatric surgery. The drug levels were used as additional input for clinical decision-making. All four patients required TKI switches and/or dose modifications to achieve an effective and tolerable treatment. Eventually, adequate clinical and molecular remissions were achieved in all cases. In summary, TKI concentrations of patients undergoing bariatric surgery may be subtherapeutic. Moreover, there is substantial interindividual and intraindividual variation, which may be explained by the complex interference of bariatric surgery and associated weight loss. For clinical practice, therapeutic drug monitoring is advised in patients with a history of bariatric surgery in case of suboptimal response or loss of response.

10.
Neuropharmacology ; 259: 110100, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39117105

RESUMEN

Stinels are a novel class of N-methyl-d-aspartate glutamate receptor (NMDAR) positive allosteric modulators. We explored mechanism of action and NR2 subtype specificity of the stinel zelquistinel (ZEL) in HEK 293 cells expressing recombinant NMDARs. ZEL potently enhanced NMDAR current at NR2A (EC50 = 9.9 ± 0.5 nM) and NR2C-containing (EC50 = 9.7 ± 0.6 nM) NMDARs, with a larger ceiling enhancement at NR2B-NMDAR (EC50 = 35.0 ± 0.7 nM), while not affecting NR2D-containing NMDARs. In cells expressing NR2A and NR2C-containing NMDARs, ZEL exhibited an inverted-U dose-response relation, with a low concentration enhancement and high concentration suppression of NMDAR currents. Extracellular application of ZEL potentiated NMDAR receptor activity via prolongation of NMDAR currents. Replacing the slow Ca2+ intracellular chelator EGTA with the fast chelator BAPTA blocked ZEL potentiation of NMDARs, suggesting an action on intracellular Ca2+-calmodulin-dependent inactivation (CDI). Consistent with this mechanism of action, removal of the NR1 intracellular C-terminus, or intracellular infusion of a calmodulin blocking peptide, blocked ZEL potentiation of NMDAR current. In contrast, BAPTA did not prevent high-dose suppression of current, indicating this effect has a different mechanism of action. These data indicate ZEL is a novel positive allosteric modulator that binds extracellularly and acts through a unique long-distance mechanism to reduce NMDAR CDI, eliciting enhancement of NMDAR current. The critical role that NMDARs play in long-term, activity-dependent synaptic plasticity, learning, memory and cognition, suggests dysregulation of CDI may contribute to psychiatric disorders such as depression, schizophrenia and others, and that the stinel class of drugs can restore NMDAR-dependent synaptic plasticity by reducing activity-dependent CDI.


Asunto(s)
Calcio , Receptores de N-Metil-D-Aspartato , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Humanos , Células HEK293 , Calcio/metabolismo , Relación Dosis-Respuesta a Droga , Regulación Alostérica/efectos de los fármacos , Regulación Alostérica/fisiología , Sesterterpenos/farmacología , Animales
11.
Metab Eng ; 85: 35-45, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39019251

RESUMEN

Colistin, also known as polymyxin E, is a lipopeptide antibiotic used to treat infections caused by multidrug-resistant gram-negative bacteria. It is considered a "last-line antibiotic", but its clinical development is hindered by low titer and impurities resulting from the presence of diverse homologs in microbial fermentation. To ensure consistent pharmaceutical activity and kinetics, it is crucial to have high-purity colistin active pharmaceutical ingredient (API) in the pharmaceutical industry. This study focused on the metabolic engineering of a natural colistin producer strain to produce colistin with a high titer and purity. Guided by genome mining, we identified Paenibacillus polymyxa ATCC 842 as a natural colistin producer capable of generating a high proportion of colistin A. By systematically inactivating seven non-essential biosynthetic gene clusters (BGCs) of peptide metabolites that might compete precursors with colistin or inhibit colistin production, we created an engineered strain, P14, which exhibited an 82% increase in colistin titer and effectively eliminated metabolite impurities such as tridecaptin, paenibacillin, and paenilan. Additionally, we engineered the L-2,4-diaminobutyric acid (L-2,4-DABA) pathway to further enhance colistin production, resulting in the engineered strain P19, which boosted a remarkable colistin titer of 649.3 mg/L - a 269% improvement compared to the original strain. By concurrently feeding L-isoleucine and L-leucine, we successfully produced high-purity colistin A, constituting 88% of the total colistin products. This study highlights the potential of metabolic engineering in improving the titer and purity of lipopeptide antibiotics in the non-model strain, making them more suitable for clinical use. These findings indicate that efficiently producing colistin API in high purity directly from fermentation can now be achieved in a straightforward manner.


Asunto(s)
Antibacterianos , Colistina , Ingeniería Metabólica , Paenibacillus polymyxa , Colistina/metabolismo , Colistina/biosíntesis , Paenibacillus polymyxa/genética , Paenibacillus polymyxa/metabolismo , Antibacterianos/biosíntesis , Antibacterianos/metabolismo , Familia de Multigenes
12.
Zhen Ci Yan Jiu ; 49(7): 700-706, 2024 Jul 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-39020488

RESUMEN

OBJECTIVES: To observe the efficacy and safety of ginger-partitioned moxibustion combined with ringheaded thumb-tack needle stimulation in the prevention and treatment of chemotherapy-induced nausea and vomiting (CINV) in patients with malignant tumors. METHODS: Patients with malignant tumors and suffering from chemotherapy were randomly divided into control group (35 cases, 4 cases dropped off) and observation group (35 cases, 2 cases dropped off). The patients of the control group were treated by orally taking ondansetron hydrochloride tablets 8 mg/time, 3 times a day for 3 d, and those of the observation group treated by ginger-partitioned moxibustion combined with ringheaded thumb-tack needle stimulation of Zusanli(ST36), Neiguan(PC6), Tianshu(ST25), Zhongwan(CV12) and Guanyuan(CV4) once a day for a total of 3 d, based on the treatment of the control group. The patients' gastrointestinal reaction degree after the 1st , 2nd and the 3rd day of treatment were recorded. The Karnofsky performance status (KPS) score (0-100 points) was used for assessing the patients' quality of life. The TCM syndrome score (4 grades:no, mild, medium and severe, i.e. 0, 2, 4 and 6 points) was given according to the patients' severity of symptoms of spleen (stomach) qi deficiency (nausea and vomiting, abdominal distension after eating, belching, loss of appetite, weakness and laziness to speak, fatigue, and loose stool). The safety of the treatment was assessed by examining the patients' blood routine, liver function and kidney function, and the adverse reactions including blisters, allergies, burns and fainting during acupuncture treatment. RESULTS: After the 2nd and 3rd day of treatment, the patients conditions of vomiting and nausea in the observation group were significantly better than those of the control group (P<0.05). The TCM syndrome score and KPS score were significantly decreased in comparison with those of pre-treatment in both groups (P<0.05), and the TCM syndrome score was obviously lower in the observation group than in the control group (P<0.05). No significant differences were found between the two groups in the KPS score after the treatment , and in the levels of white blood cells (WBC), hemoglobin (HGB), platelets (PLT), absolute neutrophil count (ANC), alanine transaminase (ALT), aspartate aminotransferase (AST), creatinine(Cr), and blood urea nitrogen (BUN). CONCLUSIONS: The use of ginger-partitioned moxibustion combined with ringheaded thumb-tack needle stimulation is safe for CINV patients, and can effectively relieve nausea and vomiting and alleviate digestive symptoms.


Asunto(s)
Moxibustión , Náusea , Neoplasias , Vómitos , Zingiber officinale , Humanos , Masculino , Persona de Mediana Edad , Femenino , Zingiber officinale/química , Adulto , Neoplasias/terapia , Neoplasias/tratamiento farmacológico , Anciano , Náusea/terapia , Náusea/etiología , Náusea/prevención & control , Vómitos/terapia , Puntos de Acupuntura , Adulto Joven , Terapia por Acupuntura , Antineoplásicos/efectos adversos , Tracto Gastrointestinal/fisiopatología
13.
Cell ; 187(16): 4272-4288.e20, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39013469

RESUMEN

Vesicle trafficking is a fundamental process that allows for the sorting and transport of specific proteins (i.e., "cargoes") to different compartments of eukaryotic cells. Cargo recognition primarily occurs through coats and the associated proteins at the donor membrane. However, it remains unclear whether cargoes can also be selected at other stages of vesicle trafficking to further enhance the fidelity of the process. The WDR11-FAM91A1 complex functions downstream of the clathrin-associated AP-1 complex to facilitate protein transport from endosomes to the TGN. Here, we report the cryo-EM structure of human WDR11-FAM91A1 complex. WDR11 directly and specifically recognizes a subset of acidic clusters, which we term super acidic clusters (SACs). WDR11 complex assembly and its binding to SAC-containing proteins are indispensable for the trafficking of SAC-containing proteins and proper neuronal development in zebrafish. Our studies thus uncover that cargo proteins could be recognized in a sequence-specific manner downstream of a protein coat.


Asunto(s)
Microscopía por Crioelectrón , Transporte de Proteínas , Pez Cebra , Humanos , Animales , Endosomas/metabolismo , Células HEK293 , Células HeLa , Proteínas de Pez Cebra/metabolismo , Proteínas de Pez Cebra/química , Unión Proteica
14.
Acta Pharmacol Sin ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992119

RESUMEN

The escalating obesity epidemic and aging population have propelled metabolic dysfunction-associated steatohepatitis (MASH) to the forefront of public health concerns. The activation of FXR shows promise to combat MASH and its detrimental consequences. However, the specific alterations within the MASH-related transcriptional network remain elusive, hindering the development of more precise and effective therapeutic strategies. Through a comprehensive analysis of liver RNA-seq data from human and mouse MASH samples, we identified central perturbations within the MASH-associated transcriptional network, including disrupted cellular metabolism and mitochondrial function, decreased tissue repair capability, and increased inflammation and fibrosis. By employing integrated transcriptome profiling of diverse FXR agonists-treated mice, FXR liver-specific knockout mice, and open-source human datasets, we determined that hepatic FXR activation effectively ameliorated MASH by reversing the dysregulated metabolic and inflammatory networks implicated in MASH pathogenesis. This mitigation encompassed resolving fibrosis and reducing immune infiltration. By understanding the core regulatory network of FXR, which is directly correlated with disease severity and treatment response, we identified approximately one-third of the patients who could potentially benefit from FXR agonist therapy. A similar analysis involving intestinal RNA-seq data from FXR agonists-treated mice and FXR intestine-specific knockout mice revealed that intestinal FXR activation attenuates intestinal inflammation, and has promise in attenuating hepatic inflammation and fibrosis. Collectively, our study uncovers the intricate pathophysiological features of MASH at a transcriptional level and highlights the complex interplay between FXR activation and both MASH progression and regression. These findings contribute to precise drug development, utilization, and efficacy evaluation, ultimately aiming to improve patient outcomes.

15.
ACS Appl Mater Interfaces ; 16(32): 42332-42342, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39084210

RESUMEN

Lithium metal anode has attracted wide attention due to its ultrahigh theoretical specific capacity, lowest reduction potential, and low density. However, uncontrollable dendritic growth and volume change caused by uneven Li+ deposition still seriously hinder the large-scale commercial application of lithium metal batteries, even causing serious battery explosions and other safety problems. Hence, gold nanoparticles with a gradient distribution anchored on 3D carbon fiber paper (CP) current collectors followed by the encapsulation of polydopamine (PDA) (CP/Au/PDA) are constructed for stable and dendrite-free Li metal anodes for the first time. Significantly, lithiophilic Au nanoparticles showing a gradient distribution in the carbon fiber paper could guide the transfer of Li+ from the outside to the inside of the CP/Au/PDA electrode as well as lower the nucleation overpotential of Li, thereby obtaining the uniform Li deposition. Meanwhile, the PDA layer could in situ be converted to Li-PDA which could serve as an efficient Li+ conductor to further facilitate uniform Li+ transport among the whole CP/Au/PDA electrode. Besides, 3D carbon fiber paper could effectively accommodate the volume change during the plating/stripping process of Li metal. As a result, CP/Au/PDA electrodes deliver a low nucleation overpotential (∼9 mV) and a high Coulombic efficiency (mean value of ∼98.8%) at a current density of 1 mA cm-2 with the capacity of 1 mA h cm-2. Furthermore, Li@CP/Au/PDA electrodes also can demonstrate an ultralow voltage hysteresis (∼20 mV) and a long cycle life (1000 h) in symmetric cells. Finally, with LiFePO4 (LFP) as the cathode, the Li@CP/Au/PDA-LFP full cell delivers a high discharge capacity of 136 mA h g-1 even after 350 cycles at 1C, exhibiting a per cycle loss as low as 0.01%. This gradient lithium ion regulation current collector is of great significance for the development of lithium metal anodes.

18.
Int J Biol Macromol ; 276(Pt 1): 133272, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38906352

RESUMEN

This study aims to investigate the effect of pulsed electric field (PEF) assisted OSA esterification treatment on the multi-scale structure and digestive properties of cassava starch and structure-digestion relationships. The degree of substitution (DS) of starch dually modified at 1.5-4.5 kV/cm was 37.6-55.3 % higher than that of starch modified by the conventional method. Compared with native starch, the resistant starch (RS) content of esterified starch treated with 3 kV/cm significantly increased by 17.13 %, whereas that of starch produced by the conventional method increased by only 5.91 %. Furthermore, assisted esterification at low electric fields (1.5-3 kV/cm) promotes ester carbonyl grafting on the surface of starch granules, increases steric hindrance and promotes the rearrangement of the amorphous regions of starch, which increases the density of the double-helical structure. These structural changes slow down starch digestion and increase the RS content. Therefore, this study presents a potential method for increasing the RS content of starch products using PEF to achieve the desired digestibility.


Asunto(s)
Electricidad , Manihot , Almidón , Manihot/química , Esterificación , Almidón/química , Almidón Resistente
19.
Int J Pharm ; 660: 124298, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-38825172

RESUMEN

One of the most common forms of controlled release technology for oral drug delivery comprises an active ingredient dispersed in a hydrophilic matrix forming polymer such as hydroxypropyl methylcellulose (HPMC), which is tableted via direct compression. However, HPMC may pose problems in direct compression due to its poor flowability. Hence, mannitol syrup was spray-coated over fluidized HPMC particles to produce co-processed HPMC-mannitol at ratios of 20:80, 50:50, and 70:30. Particles of pure HPMC, co-processed HPMC-mannitol, and their respective physical mixtures were evaluated for powder flowability, compression profiles, and controlled release performance. It was found that co-processed HPMC-mannitol consisted of particles with improved flow compared to pure HPMC particles. Sufficiently strong tablets of >2 MPa could be produced at moderate to high compression forces of 150-200 MPa. The dissolution profile could be tuned to obtain desired release profiles by altering HPMC-mannitol ratios. Co-processed HPMC-mannitol offers an interesting addition to the formulator's toolbox in the design of controlled release formulations for direct compression.


Asunto(s)
Preparaciones de Acción Retardada , Liberación de Fármacos , Excipientes , Derivados de la Hipromelosa , Manitol , Comprimidos , Manitol/química , Derivados de la Hipromelosa/química , Excipientes/química , Preparaciones de Acción Retardada/química , Solubilidad , Composición de Medicamentos/métodos , Química Farmacéutica/métodos , Polvos
20.
Nat Commun ; 15(1): 5376, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918409

RESUMEN

Kagome lattice has been actively studied for the possible realization of frustration-induced two-dimensional flat bands and a number of correlation-induced phases. Currently, the search for kagome systems with a nearly dispersionless flat band close to the Fermi level is ongoing. Here, by combining theoretical and experimental tools, we present Sc3Mn3Al7Si5 as a novel realization of correlation-induced almost-flat bands in the kagome lattice in the vicinity of the Fermi level. Our magnetic susceptibility, 27Al nuclear magnetic resonance, transport, and optical conductivity measurements provide signatures of a correlated metallic phase with tantalizing ferromagnetic instability. Our dynamical mean-field calculations suggest that such ferromagnetic instability observed originates from the formation of nearly flat dispersions close to the Fermi level, where electron correlations induce strong orbital-selective renormalization and manifestation of the kagome-frustrated bands. In addition, a significant negative magnetoresistance signal is observed, which can be attributed to the suppression of flat-band-induced ferromagnetic fluctuation, which further supports the formation of flat bands in this compound. These findings broaden a new prospect to harness correlated topological phases via multiorbital correlations in 3d-based kagome systems.

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