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1.
Phytother Res ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225243

RESUMEN

Exosomes, extracellular vesicles secreted by various cells, actively participate in intercellular communication by facilitating the exchange of crucial molecular information such as DNA, RNA, and lipids. Within this intricate network, microRNAs, endogenous non-coding small RNAs, emerge as pivotal regulators of post-transcriptional gene expression, significantly influencing the development of neurodegenerative diseases. The historical prominence of traditional Chinese medicine (TCM) in clinical practice in China underscores its enduring significance. Notably, TCM monomers, serving as active constituents within herbal medicine, assume a critical role in the treatment of neurodegenerative diseases, particularly in mitigating oxidative stress, inhibiting apoptosis, and reducing inflammation. This comprehensive review aims to delineate the specific involvement of exosomal microRNAs in various neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, stroke, and amyotrophic lateral sclerosis. Furthermore, the exploration extends to the application of TCM monomers, elucidating their efficacy as therapeutic agents in these conditions. Additionally, the review examines the utilization of exosomes as drug delivery carriers in the context of neurodegenerative diseases, providing a nuanced understanding of the potential synergies between TCM and modern therapeutic approaches. This synthesis of knowledge aims to contribute to the advancement of our comprehension of the intricate molecular mechanisms underlying neurodegeneration and the potential therapeutic avenues offered by TCcom interventions.

2.
Oral Oncol ; 158: 106980, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39151333

RESUMEN

OBJECTIVE: The early response to concurrent chemoradiotherapy in patients with locally advanced nasopharyngeal carcinoma (LA-NPC) is closely correlated with prognosis. In this study, we aimed to predict early response using a combined model that combines sub-regional radiomics features from multi-sequence MRI with clinically relevant factors. METHODS: A total of 104 patients with LA-NPC were randomly divided into training and test cohorts at a ratio of 3:1. Radiomic features were extracted from subregions within the tumor area using the K-means clustering method, and feature selection was performed using LASSO regression. Four models were established: a radiomics model, a clinical model, an Intratumor Heterogeneity (ITH) score-based model and a combined model that integrates the ITH score with clinical factors. The predictive performance of these models was evaluated using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). RESULTS: Among the models, the combined model incorporating the ITH score and clinical factors exhibited the highest predictive performance in the test cohort (AUC=0.838). Additionally, the models based on ITH score showed superior prognostic value in both the training cohort (AUC=0.888) and the test cohort (AUC=0.833). CONCLUSION: The combined model that integrates the ITH score with clinical factors exhibited superior performance in predicting early response following concurrent chemoradiotherapy in patients with LA-NPC.


Asunto(s)
Imagen por Resonancia Magnética , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Masculino , Femenino , Imagen por Resonancia Magnética/métodos , Carcinoma Nasofaríngeo/diagnóstico por imagen , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/patología , Persona de Mediana Edad , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/terapia , Neoplasias Nasofaríngeas/patología , Adulto , Quimioradioterapia/métodos , Anciano , Pronóstico , Resultado del Tratamiento , Curva ROC
3.
Heliyon ; 10(12): e32184, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39021897

RESUMEN

Poly(N-isopropylacrylamide) (PNIPAM) nanogels are promising responsive colloidal particles that can be used in pharmaceutical applications as drug carriers. This work investigates the temperature-dependent morphological changes and agglomeration of PNIPAM nanogels in the presence of mono- and multi-valent cationic electrolytes. We described the deswelling, flocculation, thermal reversibility behaviour and aggregated morphology of PNIPAM nanogels over a range of electrolyte concentrations and temperatures revealing the critical transition points from stable suspension to spontaneous agglomeration. We demonstrated that the flocculating ability and the rate of aggregate formation follow the order of deswelling behaviour. Transmission electron microscopy and atomic force microscopy analysis revealed the presence of a shell-like layer with varying density in the multivalent electrolyte solutions when compared to those in aqueous medium. We identified a concentration threshold of the thermally induced reversible aggregation/dispersion for the PNIPAM nanogels in the presence of Na+ and K+ ions at 10 mM, for Mg2+ and Ca2+ ions at 1 mM and for Al3+ ions at 0.1 mM concentrations. Such concentration thresholds indicated the effective destabilization of the electrolyte system with multivalency following the Schulze-Hardy rule. Our findings were supported by applying a Debye screening model that accounts for the shielding effect of multivalent cationic electrolytes on these nanogel systems. Our experiments and the models confirmed the compression of the electric double layer as the valency and ionic strength increased, except for Al3+ at higher concentrations which seemed to disrupt the electrical double layer and cause reversal of zeta potential. Our work highlights the significant impact the presence of multivalent cations can impose on the stability and morphology of nanogels, and this understanding will help in designing responsive nanogel systems based on PNIPAM nanogels.

4.
Oral Oncol ; 154: 106865, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823173

RESUMEN

OBJECTIVE: The aim of this study is to evaluate the efficacy and cost-effectiveness of various induction chemotherapy (IC) regimens as first-line treatment for Locoregionally advanced nasopharyngeal carcinoma (LA-NPC), aiming to provide clinicians and patients with informed insights to aid in treatment decision-making. PATIENTS AND METHODS: We conducted a network meta-analysis (NMA) and cost-effectiveness analysis (CEA) based on data from 10 clinical trials investigating IC regimens for the treatment of LA-NPC. A Bayesian NMA was performed, with the primary outcomes being hazard ratios (HRs) for disease-free survival (DFS) and overall survival (OS). To model the disease progression of LA-NPC, we developed a dynamic partitioned survival model consisting of three disease states: progression-free survival (PFS), progression disease (PD), and death. The model was run on a 3-week cycle for a research period of 10 years, with quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs) serving as outcome measures. RESULTS: According to the surface under the cumulative ranking curve (SUCRA) estimates derived from the NMA, TPC and TP, as IC regimens, appear to exhibit superior efficacy compared to other treatment modalities. In terms of CEA, concurrent chemoradiotherapy (CCRT), TPF + CCRT, and GP + CCRT were found to be dominated (more costs and less QALYs). Comparatively, TPC + CCRT emerged as a cost-effective option with an ICER of $1260.57/QALY when compared to PF + CCRT. However, TP + CCRT demonstrated even greater cost-effectiveness than TPC + CCRT, with an associated increase in costs of $3300.83 and an increment of 0.1578 QALYs per patient compared to TPC + CCRT, resulting in an ICER of $20917.62/QALY. CONCLUSION: Based on considerations of efficacy and cost-effectiveness, the TP + CCRT treatment regimen may emerge as the most favorable first-line therapeutic approach for patients with LA-NPC.


Asunto(s)
Análisis Costo-Beneficio , Quimioterapia de Inducción , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Metaanálisis en Red , Humanos , Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/economía , Carcinoma Nasofaríngeo/mortalidad , Quimioterapia de Inducción/economía , Quimioterapia de Inducción/métodos , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/economía , Años de Vida Ajustados por Calidad de Vida , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/economía , Análisis de Costo-Efectividad
5.
Medicine (Baltimore) ; 103(23): e38418, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847680

RESUMEN

BACKGROUND: Previous findings on the effect of general versus spinal anesthesia on postoperative delirium in elderly people with hip fractures are somewhat controversial. This article included the latest randomized controlled study for meta-analysis to evaluate the effect of general anesthesia (GA) and spinal anesthesia (SA) on delirium after hip fracture surgery in the elderly, so as to guide the clinical. METHODS: Cochrane Library, PubMed, Web Of Science, and Embase were searched from inception up to January 16, 2024. Randomized controlled trial (RCT) was included to evaluate the postoperative results of GA and SA in elderly patients (≥50 years old) undergoing hip fracture surgery. Two researchers independently screened for inclusion in the study and extracted data. Heterogeneity was assessed by the I²and Chi-square tests, and P < .1 or I² ≥ 50% indicated marked heterogeneity among studies. The Mantel-Haenszel method was used to estimate the combined relative risk ratio (RR) and the corresponding 95% confidence interval (CI) for the binary variables. RESULTS: Nine randomized controlled trials were included. There was no significant difference (RR = 0.93, 95% CI = 0.774-1.111, P > .05) in the incidence of postoperative delirium between the GA group and the SA group. In intraoperative blood transfusion (RR = 1.0, 95% CI = 0.77-1.28, Z = 0.04, P = .971), pulmonary embolism (RR = 0.795, 95% CI = 0.332-1.904, Z = 0.59, P = .606), pneumonia (RR = 1.47, 95% CI = 0.75-2.87, P = .675), myocardial infarction (RR = 0.97, 95% CI = 0.24-3.86, Z = 0.05, P = .961), heart failure (RR = 0.80, 95% CI = 0.26-2.42, Z = 0.40, P = .961), urinary retention (RR = 1.42, 95% CI = 0.77-2.61, Z = 1.11, P = .267) were similar between the 2 anesthetic techniques. CONCLUSION: There is no significant difference in the effect of GA and SA on postoperative delirium in elderly patients with hip fracture, and their effects on postoperative complications are similar.


Asunto(s)
Anestesia General , Anestesia Raquidea , Delirio , Fracturas de Cadera , Complicaciones Posoperatorias , Ensayos Clínicos Controlados Aleatorios como Asunto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Anestesia General/efectos adversos , Anestesia General/métodos , Anestesia Raquidea/efectos adversos , Anestesia Raquidea/métodos , Delirio/etiología , Delirio/epidemiología , Delirio/prevención & control , Delirio del Despertar/epidemiología , Delirio del Despertar/prevención & control , Delirio del Despertar/etiología , Fracturas de Cadera/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Persona de Mediana Edad
6.
Anal Chim Acta ; 1307: 342619, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719412

RESUMEN

BACKGROUND: The micro gas chromatography column (µGCC) is one of the key components of the miniaturized gas chromatography system. However, light alkanes are difficult to be separated by a micro gas chromatography column, especially for methane and ethane, because the length of µGCC is limited by the area of a silicon substrate. More importantly, the heterogeneous microchannel surface formed by silicon glass bonding causes uneven stationary phase coating and the forces between the untreated microchannel surfaces and the stationary phase materials are weak, which will prevent the improvement of separation performance. RESULTS: In this paper, a micro gas chromatography column (µGCC) with uniform HKUST-1 stationary phase is reported. Significantly, an alumina film prepared by the atomic layer deposition (ALD) technique is used to homogenize the heterogeneous microchannels. The alumina is a hydrophilic material and the alumina made by the ALD technique is uniform. The forces between hydrophilic alumina film and HKUST-1 are strong, which can greatly improve the coating uniformity of the hydrophilic stationary phase HKUST-1. The test results show that the µGCC could baseline separate the light alkane mixtures (CH4, C2H6, C3H8, and C4H10) at the high testing temperature of 120 °C. The maximum resolution of the difficult-separated methane and ethane reached 19.2, which is 108 % higher than the µGCC using the same stationary phase without homogenizing the microchannel inner surface. SIGNIFICANCE: The µGCC uses ALD alumina film to homogenize the microchannel inner surface; meanwhile, hydrophilic ALD alumina has a strong electrostatic attraction with the hydrophilic stationary phase HKUST-1. Homogeneous microchannel surface and strong electrostatic attraction are favorable to obtain uniform stationary phase which greatly improves the separation performance, resulting in a large resolution for methane and ethane. The µGCC has broad application prospects in light alkane separation.

7.
Foods ; 13(10)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38790822

RESUMEN

Cereal and legume proteins, pivotal for human health, significantly influence the quality and stability of processed foods. Despite their importance, the inherent limited functional properties of these natural proteins constrain their utility across various sectors, including the food, packaging, and pharmaceutical industries. Enhancing functional attributes of cereal and legume proteins through scientific and technological interventions is essential to broadening their application. Cold plasma (CP) technology, characterized by its non-toxic, non-thermal nature, presents numerous benefits such as low operational temperatures, lack of external chemical reagents, and cost-effectiveness. It holds the promise of improving proteins' functionality while maximally retaining their nutritional content. This review delves into the pros and cons of different cold plasma generation techniques, elucidates the underlying mechanisms of protein modification via CP, and thoroughly examines research on the application of cold plasma in augmenting the functional properties of proteins. The aim is to furnish theoretical foundations for leveraging CP technology in the modification of cereal and legume proteins, thereby enhancing their practical applicability in diverse industries.

8.
Small Methods ; : e2400179, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38763915

RESUMEN

Interface strain significantly affects the band structure and electronic states of metal-nanocrystal-2D-semiconductor heterostructures, impacting system performance. While transmission electron microscopy (TEM) is a powerful tool for studying interface strain, its accuracy may be compromised by sample overlap in high-resolution images due to the unique nature of the metal-nanocrystals-2D-semiconductors heterostructure. Utilizing digital dark-field technology, the substrate influence on metal atomic column contrasts is eliminated, improving the accuracy of quantitative analysis in high-resolution TEM images. Applying this method to investigate Pt on MoS2 surfaces reveals that the heterostructure introduces a tensile strain of ≈3% in Pt nanocrystal. The x-directional linear strain in Pt nanocrystals has a periodic distribution that matches the semi-coherent interface between Pt nanocrystals and MoS2, while the remaining strain components localize mainly on edge atomic steps. These results demonstrate an accurate and efficient method for studying interface strain and provide a theoretical foundation for precise heterostructure fabrication.

9.
Cancer Control ; 31: 10732748241255535, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38773761

RESUMEN

The current standard treatment for locally advanced squamous cell carcinoma of the head and neck (LASCCHN) comprises concurrent radiotherapy (CRT) alongside platinum-based chemotherapy. However, innovative therapeutic alternatives are being evaluated in phase II/III randomized trials. This study employed a Bayesian network meta-analysis (NMA) using fixed effects to provide both direct and indirect comparisons of all existing treatment modalities for unresectable LASCCHN. METHODS: We referenced randomized controlled trials (RCTs) from January 2000 to July 2023 by extensively reviewing PubMed, EMBASE, and Web of Science databases, adhering to the Cochrane methodology. Relevant data, including summary estimates of overall survival (OS) and progression-free survival (PFS), were extracted from these selected studies and recorded in a predefined database sheet. Subsequently, we conducted a random effects network meta-analysis using a Bayesian framework. RESULTS: Based on the Surface Under the Cumulative Ranking (SUCRA) values, the league table organizes the various treatments for OS in the following order: IC + RT&MTT, MTT-CRT, IC + CRT&MTT, CRT, IC + CRT, MTT-RT, IC + MTT-RT, and RT. In a similar order, the treatments rank as follows according to the league table: IC + CRT&MTT, MTT-CRT, IC + CRT, IC + RT&MTT, CRT, IC + MTT-RT, MTT-RT, and RT. Notably, none of these treatments showed significant advantages over concurrent chemoradiotherapy. CONCLUSION: Despite concurrent chemoradiotherapy being the prevailing treatment for LASCCHN, our findings suggest the potential for improved outcomes when concurrent chemoradiotherapy is combined with targeted therapy or induction chemotherapy.


The current standard treatment for advanced head and neck cancer involves combining radiation therapy with chemotherapy. However, there are ongoing trials exploring alternative therapies. In this study, we conducted a comprehensive analysis of existing treatments using a statistical method called network meta-analysis. Our analysis included data from randomized controlled trials published between January 2000 and July 2023. We focused on overall survival and progression-free survival as key outcome measures. The results of our analysis showed that none of the alternative treatments demonstrated significant advantages over the standard concurrent chemoradiotherapy. Nevertheless, there is potential for improved outcomes when targeted therapy or induction chemotherapy is combined with concurrent chemoradiotherapy.


Asunto(s)
Neoplasias de Cabeza y Cuello , Metaanálisis en Red , Carcinoma de Células Escamosas de Cabeza y Cuello , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/terapia , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Quimioradioterapia/métodos , Teorema de Bayes , Ensayos Clínicos Controlados Aleatorios como Asunto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
10.
Food Chem ; 452: 139282, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38723562

RESUMEN

Acrylamide (AA) is a neoformed compound in heated foods, mainly produced between asparagine (Asn) and glucose (Glc) during the Maillard reaction. Galacturonic acid (GalA), the major component of pectin, exhibits high activity in AA formation. This study investigated the pathway for AA formation between GalA and Asn. Three possible pathways were proposed: 1) The carbonyl group of GalA directly interacts with Asn to produce AA; 2) GalA undergoes an oxidative cleavage reaction to release α-dicarbonyl compounds, which subsequently leads to AA production; 3) 5-formyl-2-furancarboxylic acid, the thermal degradation product of GalA, reacts with Asn to generate AA. Structural analysis revealed that the COOH group in GalA accelerated intramolecular protonation and electron transfer processes, thereby increasing the formation of AA precursors such as decarboxylated Schiff base and α-dicarbonyl compounds, promoting AA formation. This study provides a theoretical basis and new insights into the formation and control of AA.


Asunto(s)
Acrilamida , Ácidos Hexurónicos , Acrilamida/química , Ácidos Hexurónicos/química , Reacción de Maillard , Asparagina/química , Calor , Pectinas/química , Estructura Molecular
11.
Nanomaterials (Basel) ; 14(5)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38470730

RESUMEN

Polydimethylsiloxane (PDMS) has emerged as a promising candidate for the dielectric layer in implantable sensors due to its exceptional biocompatibility, stability, and flexibility. This study introduces an innovative approach to produce graphene-reinforced PDMS (Gr-PDMS), where graphite powders are exfoliated into mono- and few-layer graphene sheets within the polymer solution, concurrently forming cross-linkages with PDMS. This method yields a uniformly distributed graphene within the polymer matrix with improved interfaces between graphene and PDMS, significantly reducing the percolation threshold of graphene dispersed in PDMS from 10% to 5%. As-synthesized Gr-PDMS exhibits improved mechanical and electrical properties, tested for potential use in capacitive pressure sensors. The results demonstrate an impressive pressure sensitivity up to 0.0273 kpa-1, 45 times higher than that of pristine PDMS and 2.5 times higher than the reported literature value. The Gr-PDMS showcases excellent pressure sensing ability and stability, fulfilling the requirements for implantable intracranial pressure (ICP) sensors.

12.
Zhongguo Zhong Yao Za Zhi ; 49(1): 55-61, 2024 Jan.
Artículo en Chino | MEDLINE | ID: mdl-38403338

RESUMEN

The theory of kidney storing essence storage, an important part of the basic theory of traditional Chinese medicine(TCM), comes from the Chapter 9 Discussion on Six-Plus-Six System and the Manifestations of the Viscera in the Plain Questions, which says that "the kidney manages closure and is the root of storage and the house of Jing(Essence)". According to this theory, essence is the fundamental substance of human life activities and it is closely related to the growth and development of the human body. Alzheimer's disease(AD) is one of the common neurodegenerative diseases, with the main pathological features of Aß deposition and Tau phosphorylation, which activate neurotoxic reactions and eventually lead to neuronal dysfunction and cell death, severely impairing the patient's cognitive and memory functions. Although research results have been achieved in the TCM treatment of AD, the complex pathogenesis of AD makes it difficult to develop the drugs capable of curing AD. The stem cell therapy is an important method to promote self-repair and regeneration, and bone marrow mesenchymal stem cells(BMSCs) as adult stem cells have the ability of multi-directional differentiation. By reviewing the relevant literature, this paper discusses the association between BMSCs and the TCM theory of kidney storing essence, and expounds the material basis of this theory from the perspective of molecular biology. Studies have shown that TCM with the effect of tonifying the kidney in the treatment of AD are associated with BMSCs. Exosomes produced by such cells are one of the main substances affecting AD. Exosomes containing nucleic acids, proteins, and lipids can participate in intercellular communication, regulate cell function, and affect AD by reducing Aß deposition, inhibiting Tau protein phosphorylation and neuroinflammation, and promoting neuronal regeneration. Therefore, discussing the prevention and treatment of exosomes and AD based on the theory of kidney storing essence will provide a new research idea for the TCM treatment of AD.


Asunto(s)
Enfermedad de Alzheimer , Exosomas , Adulto , Humanos , Enfermedad de Alzheimer/prevención & control , Enfermedad de Alzheimer/tratamiento farmacológico , Exosomas/metabolismo , Exosomas/patología , Riñón/patología , Medicina Tradicional China , Neuronas
13.
ACS Appl Mater Interfaces ; 16(8): 10764-10773, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38349253

RESUMEN

Poly(glycerol monomethacrylate) (PGMA) prepared by reversible addition-fragmentation chain transfer polymerization was investigated as an additive for high-loading iron oxide nanoparticle (IOP) 3D printable inks. The effect of adjusting the molar mass and loading of PGMA on the rheology of IOP suspensions was investigated, and an optimized ink formulation containing 70% w/w IOPs and 0.25% w/w PGMA98 at pH 10 was developed. This ink was successfully 3D printed onto various substrates and into several structures, including rectangles, high aspect ratio cylinders, letters, spiral- and comb-shaped structures, and thin- and thick-walled toroids. The effect of sintering on the mechanical properties of printed artifacts was investigated via four-point flexural and compressive testing, with higher sintering temperatures resulting in improved mechanical properties due to changes in the particle size and microstructure. The printed toroids were fabricated into inductors, and their electrical performance was assessed via impedance spectroscopy at a working frequency range of 0.001-13 MHz. There was a clear trade-off between electrical properties and sintering temperature due to a phase change between γ-Fe2O3 and α-Fe2O3 upon heating. Nevertheless, the optimized devices had a Q factor of ∼40 at 10 MHz, representing a superior performance compared to that of other inductors with iron oxide cores previously reported. Thus, this report represents a significant step toward the development of low-cost, fully aqueous, high loading, and 3D printable ceramic inks for high-performance inductors and functional devices.

14.
Analyst ; 149(5): 1579-1585, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38288594

RESUMEN

A semi-packed gas chromatographic column has the advantages of high specific surface area and low column pressure. We report that the stagnation regions formed in the adjacent posts along the channel of the semi-packed columns can decrease the area and height of chromatographic peaks, which makes it difficult to detect low-concentration mixed gases. A semi-packed column with staggered elliptic cylindrical post arrays (SC-S) made using a micro-electro-mechanical system technique is presented, and the separation performance of SC-S is compared with that of a semi-packed column with aligned elliptic cylindrical post arrays (SC-A). The simulation results show that the width of stagnation regions in SC-S is 86.89% smaller than that in SC-A. The experimental results indicate that the area and height of chromatographic peaks increased as stagnation regions reduced. In the separation of the alkane mixture from C8 through C10 with 10 ppm concentration, the chromatographic peak of decane was hardly identified in SC-A while the chromatographic peak in SC-S was still clearly visible. The chromatographic peak heights of octane and nonane were increased by 65.06% and 130.00%, respectively, in SC-S. The peak areas of octane and nonane were increased by 120.45% and 168.18%, respectively.

15.
Anal Chim Acta ; 1287: 342057, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38182335

RESUMEN

BACKGROUND: The gas chromatography column is one of the key components of the gas chromatograph and typically be miniaturized using micro-electro-mechanical system (MEMS) technology. Due to the limited area of the Si wafer, the column length of micro gas chromatographic column (µGCC) is usually much smaller than that of commercial chromatographic columns. Therefore, it is always difficult to use µGCCs to separate small molecule gas components such as light hydrocarbons. More importantly, the heterogeneous microchannel surface formed by silicon glass bonding causes uneven stationary phase coating, further preventing the improvement of separation performance. RESULTS: In this paper, a novel all-glass based µGCC with 2 m length for the separation of light hydrocarbons is proposed. The microchannels of the µGCC were directly prepared in the glass substrate by ultrafast laser assisted chemical etching (ULAE). The all-glass microchannels make the coating of the hydrophilic metal-organic frameworks (MOFs) stationary phase continuously because of the homogeneous material composition. Therefore, a widely used copper based hydrophilic MOFs HKUST-1 was used as stationary phase for coating and testing. The test results show that the µGCC which is an open tubular column can realize the baseline separation of light hydrocarbons at 100 °C. And the resolution of difficult separated compounds, methane and ethane, can reach 12.98, which is 201.86 % higher than the silica-based monolithic capillary column in the relevant research. The resolution of ethane and ethylene reaches 6.81 at 120 °C. SIGNIFICANCE: The µGCC fabricated by ULAE method is composed of all-glass and has the uniform stationary phase coating because of the homogeneous microchannel surface which greatly improve the separation performance, resulting in a large resolution for methane and ethane. The all-glass µGCC has broad application prospects in light hydrocarbon separation.

16.
Sci Total Environ ; 915: 170159, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38242449

RESUMEN

A pilot project for groundwater recharge from rivers is currently being carried out in North China Plain. To investigate the influence of river recharge on groundwater hydrochemical characteristics, dynamic monitoring and analysis of groundwater samples were conducted at a typical recharge site in the Hutuo River alluvial-pluvial fan in the North China Plain from 2019 to 2021. Hydrochemical, isotopic, and multivariate statistical analyses were used to systematically reveal the spatiotemporal variation of groundwater chemistry and its driving factors during groundwater recharge process. The results showed that the groundwater hydrochemical types and characteristics in different recharge areas and recharge periods exhibited obvious spatiotemporal differences. The groundwater type varied from HCO3·SO4-Na·Mg to HCO3·SO4-Ca·Mg in an upstream ecological area, while the groundwater type changed from SO4·HCO3-Mg·Ca to HCO3·SO4-Ca·Mg in the downstream impacted by reclaimed water. Changes in the contents of Ca2+, Mg2+ and HCO3- were mostly controlled by the water-rock interactions and mixing-dilution of recharge water, while the increases in Na+, NO3-, Cl-, SO42- and NO3- contents were mainly due to the infiltration of reclaimed water. Nitrogen and oxygen isotope (δ15N and δ18O) tests and the Bayesian isotope mixing model results further demonstrated that nitrate pollution mainly originated from anthropogenic sources, and the major contribution came from manure and sewage, with an average proportion of 64.6 %. Principal component analysis indicated that water-rock interactions, river-groundwater mixing and redox environment alternation were dominant factors controlling groundwater chemical evolution in groundwater recharge process.

17.
Front Endocrinol (Lausanne) ; 14: 1265152, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37929036

RESUMEN

Background: Polycystic ovary syndrome (PCOS) is a multifaceted disorder that impacts metabolism, reproduction, as well as endocrine function, characterized by excessive levels of androgen and insulin resistance. The gut microbiota has been implicated in the pathogenesis of PCOS. However, the precise mechanisms through which the gut microbiota influences PCOS still require further elucidation. Methods: The PCOS mouse model was established through the administration of letrozole to both conventional and antibiotics-treated mice. The evaluation of glucose metabolism, sex hormone levels, and ovarian morphology was conducted. Furthermore, the fecal samples from each group of mice were subjected to 16S rRNA gene sequencing, and functional prediction of gut microbiota was proceeded using PICRUSt2 to explore potential mechanisms. Results: By using letrozole-induced PCOS mice model, we manifested that antibiotic intervention significantly reduced the serum total testosterone level and ameliorated glucose intolerance. Antibiotic treatment reduced the number of amplicon sequence variants (ASVs), as well as the Shannon and Simpson index. Meanwhile, letrozole induced a significant increase in the Shannon and Simpson index instead of ASVs. Through random forest model analysis, the results revealed significant alterations in three distinct groups of microbiota, namely Clostridia_vadinBB60_group, Enterorhabdus, and Muribaculaceae after letrozole treatment. Further correlation analysis revealed a positive association between alterations in these microbiota and both serum total testosterone levels and the area under the curve (AUC) of blood glucose in IPGTT. The administration of antibiotics led to a decrease in the absolute abundance of 5 ASVs belonging to unclassified Clostridia_vadinBB60_group, unclassified Enterorhabdus, and unclassified Muribaculaceae, which exhibited a positive correlation with the levels of total testosterone in mice serum, as well as the area under the curve of blood glucose in IPGTT. Moreover, 25 functional pathways of gut microbiome were significantly discrepant between the letrozole-treated mice with and without antibiotics. Conclusion: These results suggest that disturbance of the gut microbiota may take participate in the progression of PCOS and manipulating the composition of the gut microbiota may be a therapeutic approach for managing PCOS.


Asunto(s)
Microbioma Gastrointestinal , Hiperandrogenismo , Síndrome del Ovario Poliquístico , Femenino , Humanos , Ratones , Animales , Síndrome del Ovario Poliquístico/metabolismo , Letrozol/uso terapéutico , Hiperandrogenismo/complicaciones , Glucemia/metabolismo , ARN Ribosómico 16S , Testosterona , Antibacterianos/efectos adversos
18.
Nano Lett ; 23(23): 11360-11367, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38010863

RESUMEN

The crystal growth kinetics is crucial for the controllable preparation and performance modulation of metal nanocrystals (NCs). However, the study of growth mechanisms is significantly limited by characterization techniques, and it is still challenging to in situ capture the growth process. Real-time and real-space imaging techniques at the atomic scale can promote the understanding of microdynamics for NC growth. Herein, the growth of Pd NCs on monolayer MoS2 under different atmospheres was in situ studied by environmental transmission electron microscopy. Introducing carbon monoxide can modulate the diffusion of Pd monomers, resulting in the epitaxial growth of Pd NCs with a uniform orientation. The electron energy loss spectroscopy and theoretical calculations showed that the CO adsorption assured the specific exposed facets and good uniformity of Pd NCs. The insight into the gas-solid interface interaction and the microscopic growth mechanism of NCs may shed light on the precise synthesis of NCs on two-dimensional (2D) materials.

19.
J Chromatogr A ; 1710: 464418, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37797421

RESUMEN

A composite material was synthesized at room temperature by performing modification of the copper benzene-1,3,5-tricarboxylate (HKUST-1) metal-organic framework material by multilayer fluorinated graphene (FG). The FG-HKUST-1 composite was used as a stationary phase for a micro gas chromatography column (µGCC) fabricated using micro-electro-mechanical system (MEMS) technology. The separation results showed that the µGCC with the FG-HKUST-1 composite stationary phase achieved a baseline separation of C1-C4 in 8 min. The retention factors for C2-C4 were 2.13, 7.14, and 12.04, respectively. The maximum relative standard deviation (RSD) of the retention times was 0.14 %. The difference in the retention time between methane and ethane was 1.11 min, with a resolution of 9.2 for methane and ethane. The retention factor of ethane and the resolution of methane and ethane were increased by 166 % and 114 %. Therefore, this µGCC is promising for separating light hydrocarbons with widely differing concentrations.


Asunto(s)
Benceno , Grafito , Grafito/química , Cobre , Cromatografía de Gases/métodos , Gases , Etano , Metano
20.
Front Endocrinol (Lausanne) ; 14: 1239276, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37693357

RESUMEN

Background: The metabolic profile of bile acids and their potential role as biomarkers in the pathogenesis of polycystic ovary syndrome (PCOS) have not been thoroughly characterized. Assessing their predictive value for PCOS is of significant importance. Methods: In this study, we enrolled 408 women with PCOS and 204 non-PCOS controls. The serum bile acid profile was measured using high-performance liquid chromatography-tandem mass spectrometry (LC/MS). We analyzed the differences in serum bile acid profiles between PCOS patients using the OPLS-DA model. Additionally, we examined the relationship between bile acid profiles and parameters related to glucose metabolism and hyperandrogenism. ROC analysis was employed to identify potential biomarkers for PCOS pathogenesis. XGboost was utilized for cross-validation. Results: The bile acid profile was found to be altered in PCOS patients. Specifically, the primary and secondary unconjugated bile acid fractions were significantly higher in the PCOS population. We identified five bile acid metabolite candidates that exhibited the most significant differences between PCOS and non-PCOS controls. DCA was associated with deposition index, fasting and postprandial insulin but was influenced by testosterone. CDCA and LCA combined with testosterone showed potential as biomarkers for the pathogenesis of PCOS. Conclusion: The circulating bile acid profile undergoes changes in PCOS. DCA is associated with deposition index, fasting and postprandial insulin and its level is influenced by testosterone. CDCA and LCA combined with testosterone have the potential to serve as biomarkers for the pathogenesis of PCOS.


Asunto(s)
Síndrome del Ovario Poliquístico , Humanos , Femenino , Síndrome del Ovario Poliquístico/diagnóstico , Testosterona , Ácidos y Sales Biliares , Cromatografía Líquida de Alta Presión , Insulina
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