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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 325: 125172, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39316861

RESUMO

Nitric oxide (NO) is an important gas signaling molecule, and endoplasmic reticulum (ER) stress induced by NO may be related to the pathogenesis of many diseases. Therefore, the development of ER-targeted fluorescent probes for NO is of great significance to investigate the relationship between ER stress and NO concentration changes in related diseases. Herein, an ER-targeted fluorescent probe (ER-Np) for sensing NO was constructed. ER-Np was served as an excellent tool for detection NO with high selectivity, sensitivity and ER-targetable ability. Moreover, fluorescence imaging experiments indicated that ER-Np is capable of imaging NO in living cells. Impressively, visualization of endogenous NO production during dithiothreitol (DTT)-induced ER stress in living cells was successfully observed. In addition, we found that serum NO levels were upregulated in epilepsy children, which opens up a new avenue for further understanding the relationship between the diagnostic of epilepsy.

2.
Sensors (Basel) ; 24(17)2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39275415

RESUMO

Face morphing attacks disrupt the essential correlation between a face image and its identity information, posing a significant challenge to face recognition systems. Despite advancements in face morphing attack detection methods, these techniques cannot reconstruct the face images of accomplices. Existing deep learning-based face de-morphing techniques have mainly focused on identity disentanglement, overlooking the morphing factors inherent in the morphed images. This paper introduces a novel face de-morphing method to restore the identity information of accomplices by predicting the corresponding de-morphing factor. To obtain reasonable de-morphing factors, a channel-wise attention mechanism is employed to perform feature interaction, and the correlation between the morphed image and the real-time captured reference image is integrated to promote the prediction of the de-morphing factor. Furthermore, the identity information of the accomplice is restored by mapping the morphed and reference images into the StyleGAN latent space and performing inverse linear interpolation using the predicted de-morphing factor. Experimental results demonstrate the superiority of this method in restoring accomplice facial images, achieving improved restoration accuracy and image quality compared to existing techniques.

4.
J Diabetes ; 16(8): e13599, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39155680

RESUMO

BACKGROUND: Beta 2-microglobulin (ß2-MG) is a component of the class I major histocompatibility complex (MHCI) and has recently been reported to be involved in type 2 diabetes mellitus (T2DM) and cardiovascular disease. However, the association of ß2-MG with left ventricular hypertrophy (LVH) in T2DM patients remains unknown. This study aims to investigate the correlation between serum ß2-MG and LVH in T2DM patients. METHODS: The retrospective analysis included 4602 eligible T2DM patients, divided into LVH and non-LVH groups based on echocardiography results. Serum ß2-MG levels were measured, and participants were categorized into four groups (Q1-Q4) by their serum ß2-MG quartile. The relationship of serum ß2-MG level with LVH was evaluated using logistic regression, restricted cubic spline (RCS), subgroup analysis, and machine learning. RESULTS: The prevalence of LVH in T2DM patients was 31.12%. Each standard deviation increase in serum ß2-MG level corresponded to a 1.17-fold increase in the prevalence of LVH [OR = 1.17, (95% CI: 1.05-1.31); p = 0.006]. When considering ß2-MG as a categorical variable (quartile), Q3 [OR = 1.36, (95% CI: 1.09-1.69); p = 0.007] and Q4 [OR = 1.77, (95% CI: 1.36-2.31); p < 0.001] had a significantly higher prevalence of LVH than Q1. RCS analysis found a nonlinear association between ß2-MG and LVH prevalence (p for nonlinearity <0.05). Additionally, machine learning results confirmed the importance of ß2-MG for LVH in T2DM patients. CONCLUSION: Elevated serum ß2-MG levels were likely to be associated with an increased prevalence of LVH in T2DM patients, suggesting its potential role in LVH development.


Assuntos
Diabetes Mellitus Tipo 2 , Hipertrofia Ventricular Esquerda , Microglobulina beta-2 , Humanos , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Hipertrofia Ventricular Esquerda/sangue , Hipertrofia Ventricular Esquerda/epidemiologia , Hipertrofia Ventricular Esquerda/etiologia , Microglobulina beta-2/sangue , Estudos Transversais , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Prevalência , Ecocardiografia , Biomarcadores/sangue , Fatores de Risco
5.
Int J Biol Macromol ; 278(Pt 2): 134372, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39134201

RESUMO

Bone tissue engineering scaffolds are an important means of repairing bone defects, but current solutions do not adequately simulate complex extracellular microenvironment fibrous structures and adjustable mechanical properties. We use template-assisted fiber freeze-shaping technology to construct silk fibroin nanofiber aerogels (SNFAs) with nanofibrous textures and adjustable mechanical properties. The parallel arranged channels, the pores, electrospun nanofibers, and silk protein conformation together constitute the hierarchical structure of SNFAs. Especially, the introduced electrospun nanofibers formed a biomimetic nanofibrous texture similar to the extracellular matrix, providing favorable conditions for cell migration and tissue regeneration. In addition, Young's modulus of SNFAs can be adjusted freely between 7 and 88 kPa. The rationally designed 3D architecture makes SNFAs perfectly mimic the fiber structure of the extracellular matrix and can adjust its mechanical properties to match the bone tissue perfectly. Finally, fiber-containing SNFAs observably promoted cell adhesion, proliferation, and differentiation, accelerating the bone repair process. The bone density in the defect area reached 0.53 g/cm3 and the bone volume/total volume (BV/TV) ratio reached 57 % at 12 weeks, respectively. It can be expected that this kind of tissue engineering scaffold with highly simulating extracellular matrix microenvironment and adjustable mechanical properties will possess broad prospects in the field of bone repair.


Assuntos
Regeneração Óssea , Fibroínas , Nanofibras , Engenharia Tecidual , Alicerces Teciduais , Nanofibras/química , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Animais , Fibroínas/química , Osso e Ossos/fisiologia , Proliferação de Células , Adesão Celular , Diferenciação Celular , Géis/química , Bombyx/química , Seda/química , Fenômenos Mecânicos
6.
Sci Total Environ ; 951: 175758, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39182787

RESUMO

Organosulfur compounds are prevalent in wastewater, presenting challenges for biodegradation, particularly in low-carbon environments. Supplementing additional carbon sources not only provides essential nutrients for microbial growth but also serves as regulators, influencing adaptive changes in biofilm and enhancing the survival of microorganisms in organosulfur-induced stress bioreactors. This study aims to elucidate the biodegradation of organosulfur under varying carbon source levels, placing specific emphasis on functional bacteria and metabolic processes. It has been observed that higher levels of carbon supplementation led to significantly improved total sulfur (TS) removal efficiencies, exceeding 83 %, and achieve a high organosulfur CH3SH removal efficiency of ~100 %. However, in the reactor with no external carbon source added, the oxidation end-product SO42- accumulated significantly, surpassing 120 mEq/m2-day. Furthermore, the TB-EPS concentration consistently increasedwith the ascending glucose concentration. The analysis of bacterial community reveals the enrichment of functional bacteria involved in sulfur metabolism and biofilm formation (e.g. Ferruginibacter, Rhodopeudomonas, Gordonia, and Thiobacillus). Correspondingly, the gene expressions related to the pathway of organosulfur to SO42- were notably enhanced (e.g. MTO increased by 27.7 %). In contrast, extra carbon source facilitated the transfer of organosulfur into amino acids in sulfur metabolism and promoted assimilation. These metabolic insights, coupled with kinetic transformation results, further validate distinct sulfur pathways under different carbon source conditions. The intricate interplay between bacteria growth regulation, pollutant biodegradation, and microbial metabolites underscores a complex network relationship that significantly contributes to efficient operation of bioreactors.


Assuntos
Bactérias , Biodegradação Ambiental , Biofilmes , Carbono , Poluentes Químicos da Água , Carbono/metabolismo , Poluentes Químicos da Água/metabolismo , Bactérias/metabolismo , Reatores Biológicos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Compostos de Enxofre/metabolismo , Águas Residuárias/microbiologia , Fenômenos Fisiológicos Bacterianos
7.
Reprod Sci ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958919

RESUMO

This study aims to assess the effectiveness of pulsed gonadotropin-releasing hormone (GnRH) micropump replacement therapy in the treatment of hypogonadotropic hypogonadism (HH) caused by primary empty sella (PES).The efficacy of pulsed GnRH replacement therapy using the micropump was evaluated in a middle-aged male patient with HH who had experienced the loss of his only child. Relevant literature was also consulted to compare the differences between pulse GnRH treatment and conventional treatment in terms of the development of secondary sexual characteristics, sex hormone levels, sperm production rate, and sperm activity rate in male patient with HH.In this report, a 45-year-old male diagnosed with HH and PES presented with fatigue and decreased libido. The main characteristics included decreased follicle stimulating hormone (FSH) levels of 0.03 mIU/mL, luteinizing hormone (LH) levels of 0.02 mIU/mL, and testosterone (T) levels of 0.72 nmol/L. Magnetic resonance imaging (MRI) revealed an empty sella. Semen analysis showed a small number of normal sperm with reduced motility. During treatment with the micropump pulse GnRH, the patient experienced no side effects and showed improvements in fatigue, reduced libido, sexual urge, anxiety, and feelings of inferiority. LH, FSH, and T levels returned to normal, while sperm activity rate increased to 79.9%. Ultimately, the patient's spouse achieved a natural pregnancy.Pulsed gonadotropin delivery using the micropump demonstrates good efficacy and tolerability, and aligns more closely with the physiological rhythm of GnRH secretion in the human body.

8.
Proc Natl Acad Sci U S A ; 121(32): e2405259121, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39078673

RESUMO

The group of moiré graphene superconductors keeps growing, and by now it contains twisted graphene multilayers as well as untwisted stacks. We analyze here the contribution of long-range charge fluctuations in the superconductivity of twisted double bilayers and helical trilayers, and compare the results to twisted bilayer graphene. A diagrammatic approach which depends on a few, well-known parameters is used. We find that the critical temperature and the order parameter differ significantly between twisted double bilayers and helical trilayers on one hand, and twisted bilayer graphene on the other. This trend, consistent with experiments, can be associated with the role played by moiré Umklapp processes in the different systems.

9.
Scand J Immunol ; : e13399, 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39073054

RESUMO

Oral mucositis (OM) is a severe side effect of anti-cancer therapy, with limited available treatments. Mesenchymal stem cells (MSCs) and their secreted extracellular vesicles (EVs) have demonstrated effective protection against OM. However, the underlying mechanism remains elusive. In the current study, we purified EVs secreted by human umbilical cord MSCs (hUC-MSC-EVs) and investigated their role in lipopolysaccharide (LPS)-induced human oral keratinocytes (HOKs). We observed that treatment with hUC-MSC-EVs significantly reduced the inflammatory response of HOKs to LPS induction. Through small RNA-seq using miRNAs extracted from hUC-MSC-EVs, we identified hsa-let-7e-5p as one of the most highly expressed miRNAs. Bioinformatic analysis data indicated that hsa-let-7e-5p may inhibit the NF-κB signalling pathway by targeting TAB2. Overexpression of the hsa-let-7e-5p inhibitor significantly attenuated the anti-inflammatory effect of hUC-MSC-EVs in LPS-induced HOKs, which could be reversed by the knockdown of TAB2. In addition, we administered hUC-MSC-EVs in a hamster model for OM and observed that these EVs alleviated OM phenotypes. Taken together, our observations suggest that hsa-let-7e-5p in hUC-MSC-EVs could protect the oral mucosa from OM by repressing TAB2 expression.

10.
Sci Total Environ ; 943: 173711, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38857799

RESUMO

Nitrate contamination of surface and ground water is a significant global challenge. Most current treatment technologies separate nitrate from water, resulting in concentrated wastestreams that need to be managed. Membrane Catalyst-film Reactors (MCfR), which utilize in-situ produced nanocatalysts attached to hydrogen-gas-permeable hollow-fiber membranes, offer a promising alternative for denitrification without generating a concentrated wastestream. In hydrogen-based MCfRs, bimetallic nano-scale catalysts reduce nitrate to nitrite and then further to di-nitrogen or ammonium. This study first investigated how different molar ratios of indium-to-palladium (In:Pd) catalytic films influenced denitrification rates in batch-mode MCfRs. We evaluated eleven In-Pd bimetallic catalyst films, with In:Pd molar ratios from 0.0029 to 0.28. Nitrate-removal exhibited a volcano-shaped dependence on In content, with the highest nitrate removal (0.19 mgNO3--N-min-1 L-1) occurring at 0.045 mol In/mol Pd. Using MCfRs with the optimal In:Pd loading, we treated nitrate-spiked tap water in continuous-flow for >60 days. Nitrate removal and reduction occurred in three stages: substantial denitrification in the first stage, a decline in denitrification efficiency in the second stage, and stabilized denitrification in the third stage. Factors contributing to the slowdown of denitrification were: loss of Pd and In catalysts from the membrane surface and elevated pH due to hydroxide ion production. Sustained nitrate removal will require that these factors be mitigated.

11.
Int J Biol Macromol ; 275(Pt 1): 133424, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945330

RESUMO

The absence of effective therapeutic targets poses considerable obstacles to the treatment of triple-negative breast cancer (TNBC). This study aimed to explore the function and mechanism of polysaccharides derived from the aerial parts of Tetrastigma hemsleyanum (THP) for the treatment of TNBC. THP exerts notable anti-TNBC effects when used alone, and its combination with Doxorubicin (DOX) effectively augments the sensitivity of TNBC cells to DOX. Through RNA sequencing, Fe2+ assays, western blotting, and transmission electron microscopy, THP was identified as a natural inducer of ferroptosis and ferritinophagy through the xCT/GSH/GPX4 and Nrf2/NCOA4/FTH1 pathways. Further research revealed that the THP branched-chain hexose directly binds to the xCT protein to inhibit its expression and promotes ferroptosis. In vivo experiments confirmed the role of THP in inducing ferroptosis and showed that THP improves the tumor microenvironment and immune function by increasing the ratio of CD4+ and CD8+ T cells to regulatory T cells and modulating cytokine levels. As demonstrated by electrocardiography, blood chemistry, and histological analyses, THP alleviates organ toxicity caused by DOX. Overall, these results suggest that THP has significant clinical potential as a natural macromolecular drug and may provide a safe and effective treatment strategy for TNBC when combined with DOX.


Assuntos
Doxorrubicina , Ferroptose , Polissacarídeos , Neoplasias de Mama Triplo Negativas , Ferroptose/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Humanos , Doxorrubicina/farmacologia , Polissacarídeos/farmacologia , Polissacarídeos/química , Animais , Feminino , Camundongos , Linhagem Celular Tumoral , Vitaceae/química , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
12.
J Hazard Mater ; 476: 134971, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38908181

RESUMO

Waste activated sludge (WAS) is a critical reservoir for antibiotic resistance genes (ARGs) due to the prevalent misuse of antibiotics. Horizontal gene transfer (HGT) is the primary mechanism for ARGs spread through mobile genetic elements (MGEs). However, the role of non-antibiotic organophosphorus flame retardants (Cl-OFRs) in ARG transmission in the WAS fermentation system remains unclear. This study examines the effects of tris(2-chloroethyl) phosphate (TCEP), a representative Cl-OFR, on ARG dynamics in WAS fermentation using molecular docking and metagenomic analysis. The results showed a 33.4 % increase in ARG abundance in the presence of TCEP. Interestingly, HGT did not appear to be the primary mechanism of ARG dissemination under TCEP stress, as evidenced by a 2.51 % decrease in MGE abundance. TCEP binds to sludge through hydrogen bonds with a binding energy of - 3.6 kJ/mol, leading to microbial damage and an increase in the proportion of non-viable cells. This interaction prompts a microbial shift toward Firmicutes with thick cell walls, which are significant ARG carriers. Additionally, TCEP induces chromosomal mutations through oxidative stress and the SOS response, contributing to ARG formation. Microorganisms also develop multidrug resistance mechanisms to expel TCEP and mitigate its toxicity. This study provides a comprehensive understanding of Cl-OFRs effects on the ARGs fates in WAS fermentation system and offers guidance for the safe and efficient treatment of Cl-OFRs and WAS.


Assuntos
Fermentação , Retardadores de Chama , Mutação , Esgotos , Retardadores de Chama/toxicidade , Esgotos/microbiologia , Compostos Organofosforados/toxicidade , Compostos Organofosforados/química , Resistência Microbiana a Medicamentos/genética , Farmacorresistência Bacteriana/genética , Simulação de Acoplamento Molecular , Genes Bacterianos , Transferência Genética Horizontal , Bactérias/genética , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Organofosfatos/toxicidade , Cromossomos Bacterianos/genética
13.
ACS Nano ; 18(24): 15779-15789, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38833666

RESUMO

The property of being stubborn and degradation resistant makes nanoplastic (NP) pollution a long-standing remaining challenge. Here, we apply a designed top-down strategy to leverage the natural hierarchical structure of waste crayfish shells with exposed functional groups for efficient NP capture. The crayfish shell-based organic skeleton with improved flexibility, strength (14.37 to 60.13 MPa), and toughness (24.61 to 278.98 MJ m-3) was prepared by purposefully removing the inorganic components of crayfish shells through a simple two-step acid-alkali treatment. Due to the activated functional groups (e.g., -NH2, -CONH-, and -OH) and ordered architectures with macropores and nanofibers, this porous crayfish shell exhibited effective removal capability of NPs (72.92 mg g-1) by physical interception and hydrogen bond/electrostatic interactions. Moreover, the sustainability and stability of this porous crayfish shell were demonstrated by the maintained high-capture performance after five cycles. Finally, we provided a postprocessing approach that could convert both porous crayfish shell and NPs into a tough flat sheet. Thus, our feasible top-down engineering strategy combined with promising posttreatment is a powerful contender for a recycling approach with broad application scenarios and clear economic advantages for simultaneously addressing both waste biomass and NP pollutants.


Assuntos
Exoesqueleto , Astacoidea , Animais , Adsorção , Porosidade , Exoesqueleto/química , Microplásticos/química , Tamanho da Partícula , Propriedades de Superfície
14.
Environ Sci Technol ; 58(26): 11514-11524, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38757358

RESUMO

PFAS (poly- and per-fluorinated alkyl substances) represent a large family of recalcitrant organic compounds that are widely used and pose serious threats to human and ecosystem health. Here, palladium (Pd0)-catalyzed defluorination and microbiological mineralization were combined in a denitrifying H2-based membrane biofilm reactor to remove co-occurring perfluorooctanoic acid (PFOA) and nitrate. The combined process, i.e., Pd-biofilm, enabled continuous removal of ∼4 mmol/L nitrate and ∼1 mg/L PFOA, with 81% defluorination of PFOA. Metagenome analysis identified bacteria likely responsible for biodegradation of partially defluorinated PFOA: Dechloromonas sp. CZR5, Kaistella koreensis, Ochrobacterum anthropic, and Azospira sp. I13. High-performance liquid chromatography-quadrupole time-of-flight mass spectrometry and metagenome analyses revealed that the presence of nitrate promoted microbiological oxidation of partially defluorinated PFOA. Taken together, the results point to PFOA-oxidation pathways that began with PFOA adsorption to Pd0, which enabled catalytic generation of partially or fully defluorinated fatty acids and stepwise oxidation and defluorination by the bacteria. This study documents how combining catalysis and microbiological transformation enables the simultaneous removal of PFOA and nitrate.


Assuntos
Biotransformação , Nitratos , Paládio , Nitratos/metabolismo , Paládio/química , Paládio/metabolismo , Catálise , Poluentes Químicos da Água/metabolismo , Fluorocarbonos/metabolismo , Caprilatos/metabolismo , Biodegradação Ambiental
15.
Adv Sci (Weinh) ; 11(24): e2309927, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38498774

RESUMO

The development of efficient and durable non-precious hydrogen evolution reaction (HER) catalysts for scaling up alkaline water/seawater electrolysis is highly desirable but challenging. Amorphous-crystalline (A-C) heterostructures have garnered attention due to their unusual atomic arrangements at hetero-interfaces, highly exposed active sites, and excellent stability. Here, a heterogeneous synthesis strategy for constructing A-C non-homogeneous interfacial centers of electrocatalysts on nanocages is presented. Isolated PdCo clusters on nanoscale islands in conjunction with Co3S4 A-C, functioning as a bifunctional site "island-sea" synergy, enable the dynamic confinement design of metal active atoms, resulting in excellent HER catalytic activity and durability. The hierarchical structure of hollow porous nanocages and nanoclusters, along with their large surface area and multi-dimensional A-C boundaries and defects, provides the catalyst with abundant active centers. Theoretical calculations demonstrate that the combination of PdCo and Co3S4 regulates the redistribution of interface electrons effectively, promoting the sluggish water-dissociation kinetics at the cluster Co sites. Additionally, PdCo-Co3S4 heterostructure nanocages exhibit outstanding HER activity in alkaline seawater and long-term stability for 100 h, which can be powered by commercial silicon solar cells. This finding significantly advances the development of alkaline seawater electrolysis for large-scale hydrogen production.

16.
Int J Biol Macromol ; 265(Pt 1): 130723, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38467227

RESUMO

Polysaccharide-stabilized emulsions have received extensive attention, but emulsifying activity of polysaccharides is poor. In this study, konjac glucomannan (KGM) and tannic acid (TA) complex (KGM-TA) was prepared via non-covalent binding to increase the polysaccharide interfacial stability. The emulsifying stabilities of KGM-TA complex-stabilized emulsions were analyzed under different TA concentrations and oil fractions. The results indicated that hydrogen bonds and hydrophobic bonds were the main binding forces for KGM-TA complex, which were closely related to TA concentrations. The interfacial tension of KGM-TA complex decreased from 20.0 mN/m to 13.4 mN/m with TA concentration increasing from 0 % to 0.3 %, indicating that TA improved the interfacial activity of KGM. Meanwhile, the contact angle of KGM-TA complex was closer to 90° with the increasing TA concentrations. The emulsifying stability of KGM-TA complex-stabilized emulsions increased in an oil mass fraction-dependent manner, reaching the maximum at 75 % oil mass fraction. Moreover, the droplet sizes of KGM-TA complex-stabilized high-internal-phase emulsions (HIPEs) decreased from 82.7 µm to 44.7 µm with TA concentration increasing from 0 to 0.3 %. Therefore, high TA concentrations were conducive to the improvement of the emulsifying stability of KGM-TA complex-stabilized HIPEs. High oil mass fraction promoted the interfacial contact of adjacent droplets, thus enhancing the non-covalent binding of KGM molecules at the interfaces with TA as bridges. Additionally, the high TA concentrations increased the gel network density in the aqueous phase, thus enhancing the emulsifying stability of emulsions. Our findings reveal the mechanisms by which polysaccharide-polyphenol complex stabilized HIPEs. Therefore, this study provides theoretical basis and references for the developments of polysaccharide emulsifier with high emulsifying capability and high-stability emulsions.


Assuntos
Mananas , Polifenóis , Polissacarídeos , Emulsões/química , Tamanho da Partícula , Polissacarídeos/química
17.
Anal Chem ; 96(8): 3480-3488, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38351592

RESUMO

To address the limitations of typical hairpin-structural molecular beacons, exploring the ability of a quasi-molecular beacon (qMB) to create label-free fluorescence biosensors is intriguing and remains a challenge. Herein, we propose the first example of modular qMB with the feature of a stimulation-responsive conformation switch to develop an aggregated Ag nanocluster (aAgNC) in a bifurcated DNA scaffold for fluorescently sensing a specific initiator (I*). This qMB was well designed to program four functional modules: I*-recognizable element adopting metastable stem-loop bihairpin structure and two DNA splits (exposed C3GT4 and locked C4AC4T) of aAgNC template that is separated by a tunable hairpin spacer for the customized combination of selective recognition and signaling readout. When presenting I* in an assay route, the specific hybridization induces the directional disassembly of the bihairpin unit, on which the qMB is configurationally switched to liberate the locked split. Thus, the bifurcated parent template pair of C3GT4/C4AC4T is proximal, affording in situ nucleation and clustering of emissive aAgNC. By collecting the fluorescence signal, the quantitative detection of I* is achieved. Benefiting from the ingenious programming of qMB, the recognizing and signaling integration actuates the construction of a facile and convenient fluorescent biosensor featuring rapid reaction kinetics, a wide linear range, high sensitivity, and specificity. This would provide a new paradigm to exploit versatile qMB-based biosensing platforms via stimulation-responsive conformation switches for developing various DNA-scaffolded Ag clusters.


Assuntos
Técnicas Biossensoriais , DNA , DNA/química , Hibridização de Ácido Nucleico , Corantes , Conformação Molecular
19.
Medicine (Baltimore) ; 103(3): e36858, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38241584

RESUMO

Sacroiliac joint (SIJ) pain leads to abnormal joint loading, and is a key risk factor for joint degeneration. This study aimed to determine the effect of tendon-bone-setting on postpartum women with SIJ pain. Multicenter retrospective review of medical records and electroencephalography reports in 10 academic medical centers. 328 postpartum women with sacroiliac joint pain were divided into 2 groups according to the methods of therapy. Group (A) (n = 203) received acupuncture combined with tendon-bone-setting for twenty days, whereas group (B) (n = 125) received only the same acupuncture for twenty days. The outcome measures were the mean values of numeric pain rating scale (NPRS), present pain intensity (PPI) scale, visual analog scale (VAS) and Japanese orthopedic association (JOA) score to evaluate pain intensity, oswestry disability index (ODI), quebec back pain disability scale (QBPDS), active straight leg raise (ASLR) and back pain function scale (BPFS) to evaluate the functional disability, pressure pain thresholds (PPT) at 5 chosen points in the sacroiliac joint region to assess pain sensitivity. All of them were evaluated before and after treatment. The effectiveness from short to long term, as well as safety was assessed in this study. A comparison of the 2 groups after treatment showed statistically significant increases in the mean values of BPFS, JOA and PPT at the 5 chosen points (P < .05), as well as significant reductions in the scores of QBPDS, ODI, ASLR, NPRS, VAS and PPI (P < .05) in favor of group (B). In addition, after treatment for 2 weeks, the considered effective rate in the group (A) was significantly higher than that in the group (B) (P < .05). Also, the cumulative incidence of pain relief at 24 months in the group (A) was greater compared with the group (B) as determined by Kaplan-Meier analysis (P < .05). Interestingly, none serious adverse event for the participants was reported. Tendon-Bone-Setting is effective and safe in treating sacroiliac joint pain for the postpartum women patients in the short and long terms through decreasing pain sensitivity and intensity, as well as improving functional ability.


Assuntos
Dor Lombar , Articulação Sacroilíaca , Humanos , Feminino , Estudos Retrospectivos , Artralgia/etiologia , Artralgia/terapia , Dor Lombar/terapia , Dor Pélvica , Período Pós-Parto , Resultado do Tratamento
20.
Environ Sci Technol ; 58(2): 1390-1398, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38165826

RESUMO

The efficient transfer of H2 plays a critical role in catalytic hydrogenation, particularly for the removal of recalcitrant contaminants from water. One of the most persistent contaminants, perfluorooctanoic acid (PFOA), was used to investigate how the method of H2 transfer affected the catalytic hydrodefluorination ability of elemental palladium nanoparticles (Pd0NPs). Pd0NPs were synthesized through an in situ autocatalytic reduction of Pd2+ driven by H2 from the membrane. The Pd0 nanoparticles were directly deposited onto the membrane fibers to form the catalyst film. Direct delivery of H2 to Pd0NPs through the walls of nonporous gas transfer membranes enhanced the hydrodefluorination of PFOA, compared to delivering H2 through the headspace. A higher H2 lumen pressure (20 vs 5 psig) also significantly increased the defluorination rate, although 5 psig H2 flux was sufficient for full reductive defluorination of PFOA. Calculations made using density functional theory (DFT) suggest that subsurface hydrogen delivered directly from the membrane increases and accelerates hydrodefluorination by creating a higher coverage of reactive hydrogen species on the Pd0NP catalyst compared to H2 delivery through the headspace. This study documents the crucial role of the H2 transfer method in the catalytic hydrogenation of PFOA and provides mechanistic insights into how membrane delivery accelerates hydrodefluorination.


Assuntos
Caprilatos , Fluorocarbonos , Nanopartículas Metálicas , Paládio , Hidrogênio
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