Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 111
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Am Chem Soc ; 146(28): 18979-18988, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38950132

RESUMO

Two-dimensional (2D) hierarchically porous metal-organic framework (MOF) nanoarchitectures with tailorable meso-/macropores hold great promise for enhancing mass transfer kinetics, augmenting accessible active sites, and thereby boosting performance in heterogeneous catalysis. However, achieving the general synthesis of 2D free-standing MOF nanosheets with controllable hierarchical porosity and thickness remains a challenging task. Herein, we present an ingenious "hard" emulsion-induced interface super-assembly strategy for preparing 2D hierarchically porous UiO-66-NH2 nanosheets with highly accessible pore channels, tunable meso-/macropore sizes, and adjustable thicknesses. The methodology relies on transforming the geometric shape of oil droplet templates within appropriate oil-in-water emulsions from conventional zero-dimensional (0D) "soft" liquid spheres to 2D "hard" solid sheets below the oil's melting/freezing point. Subsequent surfactant exchange on the surface of 2D "hard" emulsions facilitates the heterogeneous nucleation and interfacial super-assembly of in situ formed mesostructured MOF nanocomposites, serving as structural units, in a loosely packed manner to produce 2D MOF nanosheets with multimodal micro/meso-/macroporous systems. Importantly, this strategy can be extended to prepare other 2D hierarchically porous MOF nanosheets by altering metal-oxo clusters and organic ligands. Benefiting from fast mass transfer and highly accessible Lewis acidic sites, the resultant 2D hierarchically porous UiO-66-NH2 nanosheets deliver a fabulous catalytic yield of approximately 96% on the CO2 cycloaddition of glycidyl-2-methylphenyl ether, far exceeding the yield of approximately 29% achieved using conventional UiO-66-NH2 microporous crystals. This "hard" emulsion-induced interface super-assembly strategy paves a new path toward the rational construction of elaborate 2D nanoarchitecture of hierarchical MOFs with tailored physicochemical properties for diverse potential applications.

2.
Small ; 20(21): e2309956, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38145329

RESUMO

Lateral-flow assay (LFA) is one of the most commonly used detection technologies, in which the chromatographic membranes are currently used as the lateral-flow membrane (e.g., nitrocellulose membrane, NC Mem). However, several disadvantages of existing chromatographic membranes limit the performance of LFA, including relatively low flow velocity of sample solution and relatively more residuals of sample on membrane, which increase detection time and detection noise. Herein, a surface structure membrane (SS Mem) is proposed, which enables fast self-transport of water with a convection manner and realizes low residuals of sample on membrane surface after the flow. On SS Mem, the flow velocity of water is 7.1-fold higher, and the residuals of sample are decreased by 60-67%, comparing those in NC Mem. SS Mem is used as lateral-flow membrane to prepare lateral-flow strips of nanogold LFA and fluorescence LFA for rapid detection of SARS CoV-2 nucleocapsid protein. These LFAs require 210 s per detection, with limits of detection of 3.98 pg mL-1 and 53.3 fg mL-1, sensitivity of 96.5%, and specificity of 90%. The results suggest that SS Mem enables ultrafast, highly sensitive lateral-flow immunoassays and shows great potential as a new type of lateral-flow membrane to broaden the application of LFA.


Assuntos
SARS-CoV-2 , Água , Água/química , SARS-CoV-2/isolamento & purificação , Membranas Artificiais , COVID-19 , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Humanos
3.
Small ; 20(13): e2307040, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37967337

RESUMO

The practical application of Li-S batteries is still severely restricted by poor cyclic performance caused by the intrinsic polysulfides shuttle effect, which is even more severe under the high-temperature condition owing to the inevitable increase of polysulfides' solubility and diffusion rate. Herein, tungsten-doped vanadium dioxide (W-VO2) micro-flowers are employed with first-order metal-insulator phase transition (MIT) property as a robust and multifunctional modification layer to hamper the shuttle effect and simultaneously improve the thermotolerance of the common separator. Tungsten doping significantly reduces the transition temperature from 68 to 35 °C of vanadium dioxide, which renders the W-VO2 easier to turn from the insulating monoclinic phase into the metallic rutile phase. The systematic experiments and theoretical analysis demonstrate that the temperature-induced in-suit MIT property endows the W-VO2 catalyst with strong chemisorption against polysulfides, low energy barrier for liquid-to-solid conversion, and outstanding diffusion kinetics of Li-ion under high temperatures. Benefiting from these advantages, the Li-S batteries with W-VO2 modified separator exhibit significantly improved rate and long-term cyclic performance under 50 °C. Remarkably, even at an elevated temperature (80 °C), they still exhibit superior electrochemical performance. This work opens a rewarding avenue to use phase-changing materials for high-temperature Li-S batteries.

4.
Small ; : e2403710, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884192

RESUMO

Topological materials carrying topological surface states (TSSs) have extraordinary carrier mobility and robustness, which provide a new platform for searching for efficient hydrogen evolution reaction (HER) electrocatalysts. However, the majority of these TSSs originate from the sp band of topological quantum catalysts rather than the d band. Here, based on the density functional theory calculation, it is reported a topological semimetal Pd3Sn carrying TSSs mainly derived from d orbital and proposed that optimizing surface state electrons of Pd3Sn by introduction heteroatoms (Ni) can promote hybridization between hydrogen atoms and electrons, thereby reducing the Gibbs free energy (ΔGH) of adsorbed hydrogen and improving its HER performance. Moreover, this is well verified by electrocatalytic experiment results, the Ni-doped Pd3Sn (Ni0.1Pd2.9Sn) show much lower overpotential (-29 mV vs RHE) and Tafel slope (17 mV dec-1) than Pd3Sn (-39 mV vs RHE, 25 mV dec-1) at a current density of 10 mA cm-2. Significantly, the Ni0.1Pd2.9Sn nanoparticles exhibit excellent stability for HER. The electrocatalytic activity of Ni0.1Pd2.9Sn nanoparticles is superior to that of commercial Pt. This work provides an accurate guide for manipulating surface state electrons to improve the HER performance of catalysts.

5.
Diabetes Obes Metab ; 26(3): 840-850, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37994378

RESUMO

AIMS: To characterize the comparative contributions of different glycaemic indicators to cognitive dysfunction, and further investigate the associations between the most significant indicator and cognitive function, along with related cerebral alterations. MATERIALS AND METHODS: We performed a cross-sectional study in 449 subjects with type 2 diabetes who completed continuous glucose monitoring and cognitive assessments. Of these, 139 underwent functional magnetic resonance imaging to evaluate cerebral structure and olfactory neural circuit alterations. Relative weight and Sobol's sensitivity analyses were employed to characterize the comparative contributions of different glycaemic indicators to cognitive dysfunction. RESULTS: Complexity of glucose time series index (CGI) was found to have a more pronounced association with mild cognitive impairment (MCI) compared to glycated haemoglobin, time in range, and standard deviation. The proportion and multivariable-adjusted odds ratios (ORs) for MCI increased with descending CGI tertile (Tertile 1: reference group [≥4.0]; Tertile 2 [3.6-4.0] OR 1.23, 95% confidence interval [CI] 0.68-2.24; Tertile 3 [<3.6] OR 2.27, 95% CI 1.29-4.00). Decreased CGI was associated with cognitive decline in executive function and attention. Furthermore, individuals with decreased CGI displayed reduced olfactory activation in the left orbitofrontal cortex (OFC) and disrupted functional connectivity between the left OFC and right posterior cingulate gyrus. Mediation analysis demonstrated that the left OFC activation partially mediated the associations between CGI and executive function. CONCLUSION: Decreased glucose complexity closely relates to cognitive dysfunction and olfactory brain activation abnormalities in diabetes.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Adulto , Humanos , Glucose , Fatores de Tempo , Estudos Transversais , Automonitorização da Glicemia , Glicemia , Cognição , Disfunção Cognitiva/etiologia , Imageamento por Ressonância Magnética/métodos , Encéfalo/patologia
6.
J Thromb Thrombolysis ; 57(4): 558-565, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38393676

RESUMO

It is controversial whether hemodialysis affects the efficacy of the antiplatelet agents. We aimed to investigate the impact of hemodialysis on efficacies of the antiplatelet agents in coronary artery disease (CAD) patients complicated with end-stage renal disease (ESRD). 86 CAD patients complicated with ESRD requiring hemodialysis were consecutively enrolled. After 5-day treatment with aspirin and clopidogrel or ticagrelor, the platelet aggregations induced by arachidonic acid (PLAA) or adenosine diphosphate (PLADP), and the P2Y12 reaction unit (PRU) were measured before and after hemodialysis. The propensity matching score method was adopted to generate a control group with normal renal function from 2439 CAD patients. In patients taking aspirin, the PLAA remained unchanged after hemodialysis. In patients taking clopidogrel, the PLADP (37.26 ± 17.04 vs. 31.77 ± 16.09, p = 0.029) and corresponding clopidogrel resistance (CR) rate (23 [48.9%] vs. 14 [29.8%], p = 0.022) significantly decreased after hemodialysis, though PRU remained unchanged. Subgroup analysis indicated that PLADP significantly decreased while using polysulfone membrane (36.8 ± 17.9 vs. 31.1 ± 14.5, p = 0.024). In patients taking ticagrelor, PLADP, and PRU remained unchanged after hemodialysis. ESRD patients had higher incidences of aspirin resistance (AR) and CR compared to those with normal renal function (AR: 16.1% vs. 0%, p = 0.001; CR: 48.4% vs. 24.8%, p = 0.024). Hemodialysis does not have negative effect on the efficacies of aspirin, clopidogrel and ticagrelor in ESRD patients with CAD. ESRD patients have higher incidences of AR and CR compared with those with normal renal function.Trial registration ClinicalTrials.gov Identifier: NCT03330223, first registered January 4, 2018.


Assuntos
Doença da Artéria Coronariana , Falência Renal Crônica , Humanos , Inibidores da Agregação Plaquetária , Clopidogrel , Ticagrelor , Doença da Artéria Coronariana/terapia , Ticlopidina , Aspirina , Falência Renal Crônica/complicações , Diálise Renal , Difosfato de Adenosina
7.
Bioessays ; 44(12): e2200135, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36207289

RESUMO

Meiotic defects cause abnormal chromosome segregation leading to aneuploidy in mammalian oocytes. Chromosome segregation is particularly error-prone in human oocytes, but the mechanisms behind such errors remain unclear. To explain the frequent chromosome segregation errors, recent investigations have identified multiple meiotic defects and explained how these defects occur in female meiosis. In particular, we review the causes of cohesin exhaustion, leaky spindle assembly checkpoint (SAC), inherently unstable meiotic spindle, fragmented kinetochores or centromeres, abnormal aurora kinases (AURK), and clinical genetic variants in human oocytes. We mainly focus on meiotic defects in human oocytes, but also refer to the potential defects of female meiosis in mouse models.


Assuntos
Cinetocoros , Oócitos , Camundongos , Animais , Humanos , Feminino , Fuso Acromático , Meiose , Segregação de Cromossomos , Aneuploidia , Microtúbulos , Mamíferos
8.
Biol Res ; 57(1): 13, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561846

RESUMO

BACKGROUND: Endometrial fibrosis, a significant characteristic of intrauterine adhesion (IUA), is caused by the excessive differentiation and activation of endometrial stromal cells (ESCs). Glutaminolysis is the metabolic process of glutamine (Gln), which has been implicated in multiple types of organ fibrosis. So far, little is known about whether glutaminolysis plays a role in endometrial fibrosis. METHODS: The activation model of ESCs was constructed by TGF-ß1, followed by RNA-sequencing analysis. Changes in glutaminase1 (GLS1) expression at RNA and protein levels in activated ESCs were verified experimentally. Human IUA samples were collected to verify GLS1 expression in endometrial fibrosis. GLS1 inhibitor and glutamine deprivation were applied to ESCs models to investigate the biological functions and mechanisms of glutaminolysis in ESCs activation. The IUA mice model was established to explore the effect of glutaminolysis inhibition on endometrial fibrosis. RESULTS: We found that GLS1 expression was significantly increased in activated ESCs models and fibrotic endometrium. Glutaminolysis inhibition by GLS1 inhibitor bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl) ethyl sulfide (BPTES or glutamine deprivation treatment suppressed the expression of two fibrotic markers, α-SMA and collagen I, as well as the mitochondrial function and mTORC1 signaling in ESCs. Furthermore, inhibition of the mTORC1 signaling pathway by rapamycin suppressed ESCs activation. In IUA mice models, BPTES treatment significantly ameliorated endometrial fibrosis and improved pregnancy outcomes. CONCLUSION: Glutaminolysis and glutaminolysis-associated mTOR signaling play a role in the activation of ESCs and the pathogenesis of endometrial fibrosis through regulating mitochondrial function. Glutaminolysis inhibition suppresses the activation of ESCs, which might be a novel therapeutic strategy for IUA.


Assuntos
Glutamina , Mitocôndrias , Feminino , Camundongos , Humanos , Animais , Glutamina/metabolismo , Fibrose , Mitocôndrias/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , RNA/metabolismo , Endométrio/metabolismo , Endométrio/patologia
9.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33753478

RESUMO

Species in a shared environment tend to evolve similar adaptations under the influence of their phylogenetic context. Using snowfinches, a monophyletic group of passerine birds (Passeridae), we study the relative roles of ancestral and species-specific adaptations to an extreme high-elevation environment, the Qinghai-Tibet Plateau. Our ancestral trait reconstruction shows that the ancestral snowfinch occupied high elevations and had a larger body mass than most nonsnowfinches in Passeridae. Subsequently, this phenotypic adaptation diversified in the descendant species. By comparing high-quality genomes from representatives of the three phylogenetic lineages, we find that about 95% of genes under positive selection in the descendant species are different from those in the ancestor. Consistently, the biological functions enriched for these species differ from those of their ancestor to various degrees (semantic similarity values ranging from 0.27 to 0.5), suggesting that the three descendant species have evolved divergently from the initial adaptation in their common ancestor. Using a functional assay to a highly selective gene, DTL, we demonstrate that the nonsynonymous substitutions in the ancestor and descendant species have improved the repair capacity of ultraviolet-induced DNA damage. The repair kinetics of the DTL gene shows a twofold to fourfold variation across the ancestor and the descendants. Collectively, this study reveals an exceptional case of adaptive evolution to high-elevation environments, an evolutionary process with an initial adaptation in the common ancestor followed by adaptive diversification of the descendant species.


Assuntos
Aclimatação/genética , Tamanho Corporal/genética , Taxa de Mutação , Seleção Genética , Altitude , Substituição de Aminoácidos , Animais , Reparo do DNA , Proteínas Nucleares/genética , Filogenia , Especificidade da Espécie , Tibet
10.
J Am Chem Soc ; 145(30): 16498-16507, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37477359

RESUMO

As a unique class of modular nanomaterials, metal-organic framework (MOF) nanoparticles have attracted widespread interest for use in various fields because of their diverse chemical functionalities, intrinsic microporosity, and three-dimensional (3D) nanoarchitectures. However, endowing MOF nanomaterials with precisely controlled structural symmetries and hierarchical macro/mesoporosities remains a formidable challenge for the researchers. Herein, we report a facile noncentrosymmetric pore-induced anisotropic assembly strategy to prepare a series of 3D dendritic MOF (UiO-66) nanomaterials with highly controllable structural symmetries and hierarchical macro/meso/microporosities. The synthetic route of these nanomaterials depends on the anisotropic nucleation of MOF spherical nanocones with noncentrosymmetric center-radial channels and their oriented growth to isotropic nanospheres through a continuous increase in radius and solid angle. This strategy enables the controllable fabrication of asymmetric MOF nanostructures with abundant geometries and porous structures by regulating the concentration of amphiphilic triblock copolymer templates. Furthermore, the average pore diameter of the resultant MOF nanospheres can be systematically manipulated in a wide range from 35 to 130 nm by finely tuning the reaction temperature. Meanwhile, the strategy can also be extended to synthesize other MOF nanoparticles with similar architectures. Compared with microporous UiO-66 nanocrystals, the MOF nanoparticles with controllable structural symmetries and macro/meso/microporosities show enhanced catalytic activity in the CO2 cycloaddition reaction. The methodology provides new insights into the rational construction of sophisticated asymmetric open nanostructures of hierarchically porous MOFs for many potential applications.

11.
Am J Physiol Heart Circ Physiol ; 325(5): H1178-H1192, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37737736

RESUMO

Methods to augment Na+ current in cardiomyocytes hold potential for the treatment of various cardiac arrhythmias involving conduction slowing. Because the gene coding cardiac Na+ channel (Nav1.5) is too large to fit in a single adeno-associated virus (AAV) vector, new gene therapies are being developed to enhance endogenous Nav1.5 current (by overexpression of chaperon molecules or use of multiple AAV vectors) or to exogenously introduce prokaryotic voltage-gated Na+ channels (BacNav) whose gene size is significantly smaller than that of the Nav1.5. In this study, based on experimental measurements in heterologous expression systems, we developed an improved computational model of the BacNav channel, NavSheP D60A. We then compared in silico how NavSheP D60A expression vs. Nav1.5 augmentation affects the electrophysiology of cardiac tissue. We found that the incorporation of BacNav channels in both adult guinea pig and human cardiomyocyte models increased their excitability and reduced action potential duration. When compared with equivalent augmentation of Nav1.5 current in simulated settings of reduced tissue excitability, the addition of the BacNav current was superior in improving the safety of conduction under conditions of current source-load mismatch, reducing the vulnerability to unidirectional conduction block during premature pacing, preventing the instability and breakup of spiral waves, and normalizing the conduction and ECG in Brugada syndrome tissues with mutated Nav1.5. Overall, our studies show that compared with a potential enhancement of the endogenous Nav1.5 current, expression of the BacNav channels with their slower inactivation kinetics can provide greater anti-arrhythmic benefits in hearts with compromised action potential conduction.NEW & NOTEWORTHY Slow action potential conduction is a common cause of various cardiac arrhythmias; yet, current pharmacotherapies cannot augment cardiac conduction. This in silico study compared the efficacy of recently proposed antiarrhythmic gene therapy approaches that increase peak sodium current in cardiomyocytes. When compared with the augmentation of endogenous sodium current, expression of slower-inactivating bacterial sodium channels was superior in preventing conduction block and arrhythmia induction. These results further the promise of antiarrhythmic gene therapies targeting sodium channels.


Assuntos
Canal de Sódio Disparado por Voltagem NAV1.5 , Canais de Sódio Disparados por Voltagem , Humanos , Animais , Cobaias , Suínos , Potenciais de Ação , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Canais de Sódio Disparados por Voltagem/genética , Canais de Sódio Disparados por Voltagem/metabolismo , Arritmias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Sódio/metabolismo
12.
Pharmacol Res ; 187: 106607, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36509316

RESUMO

BACKGROUND: As a pathological myocardial remodeling process in a variety of cardiovascular diseases, cardiac hypertrophy still has no effective treatment. Human mesenchymal stem cells (hMSCs) derived extracellular vesicles (EVs) has been recognized as a promising treatment strategy for cardiac disease. METHODS: In this study, the inhibitory effects on cardiac hypertrophy are compared between normoxia-conditioned hMSC-derived EVs (Nor-EVs) and hypoxia-conditioned hMSC-derived EVs (Hypo-EVs) in neonatal rat cardiomyocytes (NRCMs) after angiotensin II (Ang II) stimulation and in a mouse model of transverse aortic constriction (TAC). RESULTS: We demonstrate that Hypo-EVs exert an increased inhibitory effect on cardiac hypertrophy compared with Nor-EVs. Parkinson disease protein 7 (PARK7/DJ-1) is identify as a differential protein between Nor-EVs and Hypo-EVs by quantitative proteomics analysis. Results show that DJ-1, which is rich in Hypo-EVs, alleviates mitochondrial dysfunction and excessive mitochondrial reactive oxygen species (mtROS) production as an antioxidant. Mechanistic studies demonstrate for the first time that DJ-1 may suppress cardiac hypertrophy by inhibiting the activity of proteasome subunit beta type 10 (PSMB10) through a direct physical interaction. This interaction can inhibit angiotensin II type 1 receptor (AT1R)-mediated signaling pathways resulting in cardiac hypertrophy through alleviating ubiquitination degradation of AT1R-associated protein (ATRAP). CONCLUSIONS: When taken together, our study suggests that Hypo-EVs have significant potential as a novel therapeutic agent for the treatment of cardiac hypertrophy.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Camundongos , Ratos , Humanos , Animais , Cardiomegalia/metabolismo , Proteólise , Transdução de Sinais , Vesículas Extracelulares/metabolismo , Miócitos Cardíacos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína Desglicase DJ-1/metabolismo , Proteína Desglicase DJ-1/farmacologia
13.
J Nanobiotechnology ; 21(1): 421, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37957640

RESUMO

BACKGROUND: Myocardial ischemia-reperfusion (I/R) injury is accompanied by an imbalance in the cardiac autonomic nervous system, characterized by over-activated sympathetic tone and reduced vagal nerve activity. In our preceding study, we pioneered the development of the magnetic vagus nerve stimulation (mVNS) system. This system showcased precise vagus nerve stimulation, demonstrating remarkable effectiveness and safety in treating myocardial infarction. However, it remains uncertain whether mVNS can mitigate myocardial I/R injury and its specific underlying mechanisms. In this study, we utilized a rat model of myocardial I/R injury to delve into the therapeutic potential of mVNS against this type of injury. RESULTS: Our findings revealed that mVNS treatment led to a reduction in myocardial infarct size, a decrease in ventricular fibrillation (VF) incidence and a curbing of inflammatory cytokine release. Mechanistically, mVNS demonstrated beneficial effects on myocardial I/R injury by inhibiting NLRP3-mediated pyroptosis through the M2AChR/OGDHL/ROS axis. CONCLUSIONS: Collectively, these outcomes highlight the promising potential of mVNS as a treatment strategy for myocardial I/R injury.


Assuntos
Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Estimulação do Nervo Vago , Animais , Ratos , Fenômenos Magnéticos , Infarto do Miocárdio/terapia , Traumatismo por Reperfusão Miocárdica/terapia , Traumatismo por Reperfusão Miocárdica/etiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Espécies Reativas de Oxigênio
14.
Molecules ; 28(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37241832

RESUMO

Crystalline/crystalline blends of polymer have shown advantages in the preparation of new polymeric materials. However, the regulation of co-crystallization in a blend is still full of challenges due to the preferential self-crystallization driven by thermodynamics. Here, an inclusion complex approach is proposed to facilitate the co-crystallization between crystalline polymers, because the crystallization process displays a prominent kinetics advantage when polymer chains are released from the inclusion complex. Poly(butylene succinate) (PBS), poly(butylene adipate) (PBA) and urea are chosen to form co-inclusion complexes, where PBS and PBA chains play as isolated guest molecules and urea molecules construct the host channel framework. The coalesced PBS/PBA blends are obtained by fast removing the urea framework and systematically investigated by differential scanning calorimetry, X-ray diffraction, proton nuclear magnetic resonance and Fourier transformation infrared spectrometry. It is demonstrated that PBA chains are co-crystallized into PBS extended-chain crystals in the coalesced blends, while such a phenomenon has not been detected in simply co-solution-blended samples. Though PBA chains could not be totally accommodated in the PBS extended-chain crystals, their co-crystallized content increases with the initial feeding ratio of PBA. Consequently, the melting point of the PBS extended-chain crystal gradually declines from 134.3 °C to 124.2 °C with an increasing PBA content. The PBA chains playing as defects mainly induce lattice expansion along the a-axis. In addition, when the co-crystals are soaked in tetrahydrofuran, some of the PBA chains are extracted out, leading to damage to the correlative PBS extended-chain crystals. This study shows that co-inclusion complexation with small molecules could be an effective way to promote co-crystallization behavior in polymer blends.

15.
Int Wound J ; 20(8): 2964-2972, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36965159

RESUMO

A meta-analysis study to assess the influence of instant surgery (IS) compared with conservative therapy (CT) on paediatric complicated acute appendicitis (CAA) post-surgery wounds. A comprehensive literature examination until January 2023 was implemented, and 2098 linked studies were appraised. The picked studies contained 66 674 subjects with paediatric CAA post-surgery wounds in the picked studies' baseline; 64 643 of them were using IS, and 2031 were using CT. The odds ratio (OR) in addition to 95% confidence intervals (CIs) were used to calculate the consequence of the IS compared with the CT on paediatric CAA post-surgery wounds using the dichotomous and continuous styles and a fixed or random model. The IS had a significantly higher wound infection (OR, 4.97; 95% CI, 2.35-10.54, P < .001) with moderate heterogeneity (I2  = 57%) compared with the CT in a paediatric CAA post-surgery wound. However, no significant difference was found between IS and CT in total antibiotic duration (MD, -5.34; 95% CI,-12.67 to -1.98, P = .15) with high heterogeneity (I2  = 95%) in paediatric CAA post-surgery wounds. The IS had a significantly higher wound infection; however, no significant difference was found in total antibiotic duration compared with the CT in paediatric CAA post-surgery wounds. Although precautions should be taken when commerce with the consequences because most of the studies picked for this meta-analysis had low sample sizes.


Assuntos
Apendicite , Infecção dos Ferimentos , Humanos , Criança , Apendicite/cirurgia , Tratamento Conservador , Antibacterianos/uso terapêutico , Razão de Chances , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/terapia
16.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(7): 967-978, 2023 Jul 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-37724399

RESUMO

OBJECTIVES: Trans-fatty acids (TFAs), primarily derived from the food industry's production processes, have become a globally recognized public health issue due to the detrimental impact they have on human well-being. Secoisolariciresinol diglucoside (SDG) is a polyphenolic compound derived from flax lignans, possessing antioxidative properties. This study aims to investigate the protective effect of SDG on kidney oxidative damage in offspring of mice caused by maternal exposure to TFA during pregnancy and lactation. METHODS: A total of 30 c57BL/6 female rats were randomly divided into 5 groups: a control group, a TFA-exposed group, a low-(TFA+LSDG) group, a medium-(TFA+MSDG) group, and a high-(TFA+HSDG) group (n=6 in each group). With the exception of the control group, the maternal mice in the remaining 4 groups received a daily oral gavage of TFA at a dosage of 60 mg/(kg·BW) throughout the experimental period. The mothers in the control group were administered physiological saline via oral gavage once daily. Meanwhile, the 3 SDG intervention groups were provided with ad libitum access to SDG feed containing 10 mg/kg (low), 20 mg/kg (medium), and 30 mg/kg (high) of SDG. The female mice were conceived overnight. If the vaginal plug appeared in the next morning, the female mice were conceived and included in the experimental stage until the end of the 21th day lactation period. The body weight and kidney mass of offspring were recorded, and the kidney coefficient was calculated. The kidney was detected by HE staining to observe the histopathological changes, and the level of reactive oxidative species (ROS) was detected by fluorescence probe-dihydroethidium (DHE) staining; the expression levels of total superoxide dismutase (T-SOD) and malondialdehyde (MDA) in renal homogenate were detected, and the expression of nuclear factor E2-related fator2 (Nrf2) and hemeoxygenase-1 (HO-1) protein was analyzed by immunohistochemistry (IHC) staining. The mRNA expressions of Nrf2 and HO-1 were detected by real-time PCR, and the protein expression of Cu/Zn-superoxide dismutase (Cu/Zn-SOD), Mn-superoxide dismutase (Mn-SOD), glutathione peroxidase-1 (GPx-1), Nrf2 and HO-1 were detected by Western blotting. RESULTS: Compared with the control group, the kidney coefficient in the TFA-exposed group was increased, the morphology and structure of kidney tissue was abnormal; the activity of T-SOD enzyme was decreased, and the content of MDA was increased, the level of ROS was increased; the expressions of Cu/Zn-SOD, Mn-SOD, GPx1 protein were decreased, and the mRNA and protein expressions of Nrf2 and HO-1 were decreased, there were all significant difference (all P<0.05). Compared with the TFA-exposed group, the ROS levels were reduced, and the T-SOD enzyme activity as well as the protein expression of Cu/Zn-SOD, GPx-1, Mn-SOD, Nrf2 and HO-1 were up-regulated in the low, middle and high dose SDG intervention groups; the kidney coefficient and MDA content were decreased in the middle and high dose SDG groups; the Nrf2 mRNA expression in the high dose SDG group was up-regulated, there were all significant difference (all P<0.05). CONCLUSIONS: Maternal exposure to TFA during pregnancy and lactation can lead to oxidative damage in the kidney of offspring, and the SDG intervention may alleviate TFA-induced oxidative damage by up-regulating the expression of Nrf2 and HO-1 signal pathway.


Assuntos
3,4-Metilenodioxianfetamina , Ácidos Graxos trans , Humanos , Gravidez , Feminino , Camundongos , Ratos , Animais , Ácidos Graxos trans/toxicidade , Exposição Materna , Fator 2 Relacionado a NF-E2 , Espécies Reativas de Oxigênio , Rim , Superóxido Dismutase , Estresse Oxidativo
17.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(5): 750-759, 2023 May 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-37539578

RESUMO

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease caused by inflammatory cells. Various inflammatory cells involved in RA include fibroblast-like synoviocytes, macrophages, CD4+T-lymphocytes, B lymphocytes, osteoclasts and chondrocytes. The close interaction between various inflammatory cells leads to imbalance of immune response and disorder of the expression of mRNA in inflammatory cells. It helps to drive production of pro-inflammatory cytokines and stimulate specific antigen-specific T- and B-lymphocytes to produce autoantibodies which is an important pathogenic factor for RA. Competing endogenous RNA (ceRNA) can regulate the expression of mRNA by competitively binding to miRNA. The related ceRNA network is a new regulatory mechanism for RNA interaction. It has been found to be involved in the regulation of abnormal biological processes such as proliferation, apoptosis, invasion and release of inflammatory factors of RA inflammatory cells. Understanding the ceRNA network in 6 kinds of RA common inflammatory cells provides a new idea for further elucidating the pathogenesis of RA, and provides a theoretical basis for the discovery of new biomarkers and effective therapeutic targets.


Assuntos
Artrite Reumatoide , MicroRNAs , Sinoviócitos , Humanos , Artrite Reumatoide/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Sinoviócitos/metabolismo , Sinoviócitos/patologia , Citocinas/metabolismo , RNA Mensageiro/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Proliferação de Células
18.
Int J Med Sci ; 19(2): 233-241, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35165509

RESUMO

Ovarian cancer is the second leading cause of cancer-related deaths in women, with low five-year survival rates. Therefore, it is essential to seek new treatment options. Olaparib, a PARP inhibitor, has benefited many ovarian cancer patients, but olaparib is much less effective as a single agent in 50% of patients with high grade severe tumors. Proguanil, which was originally developed as an anti-malarial drug, has gained attention due to its anti-tumor effects. Here, we evaluated the anti-tumor effect of the combination of olaparib and proguanil on ovarian cancer cells, aimed to develop a potential medical option for treating ovarian cancer patients. We examined the effect on proliferation by MTT and colony formation assays, while cell migration was measured by the transwell assay. The effect on apoptosis was measured by flow cytometry and AO/EB staining assays. Western blotting was used to detect protein expression levels in cells treated with olaparib and/or proguanil. In addition, the synergistic effect of these two drugs is calculated by CompuSyn software. The combination of olaparib and proguanil significantly increased growth suppression and apoptosis in ovarian cancer cells, compared to either single agent alone. Furthermore, results showed that the combination of olaparib and proguanil synergistically increased olaparib-induced apoptosis and DNA damage and reduced the efficiency of DNA homologous recombination repair. Our findings indicate that combination of olaparib with proguanil will be a novel potential administration route for treating ovarian cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Ftalazinas/farmacologia , Piperazinas/farmacologia , Proguanil/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Humanos , Neoplasias Ovarianas/genética
19.
Molecules ; 27(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36296685

RESUMO

Co-crystallization plays a crucial role in the integration and regulation of thermal and mechanical properties in polymer blends, but the poor compatibility of the components in the crystal phase has always been a major obstacle to co-crystallization, which puts forward stricter requests for linkage and interaction between different entities. On the basis of the hydrogen-bonding interaction that can promote chain stacking and thus improve miscibility, we propose that crystalline/crystalline blends of 2-ureido-4[1H]-pyrimidinone (UPy)-functionalized poly(butylene succinate) and poly(butylene fumarate) (PBS-UPy/PBF-UPy) where UPy groups with quadruple hydrogen-bonding interaction are employed to connect different chain ends, could inhibit phase separation and improve co-crystallization. PBS-UPy/PBF-UPy blends exhibit complex component-dependent and cooling-rate-dependent co-crystallization behavior. A high level of co-crystallization occurs in the range of PBS-UPy-rich fractions, and the proportion could approach over 98% under optimized conditions with the aid of UPy quadruple hydrogen bonds interaction. This work enriches the understanding of co-crystallization in crystalline/crystalline polymer blends and provides more possibility for the design of structures and properties of polymer materials.


Assuntos
Fumaratos , Polímeros , Cristalização , Polímeros/química , Pirimidinonas , Hidrogênio
20.
J Biol Chem ; 295(15): 5152-5162, 2020 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-32139507

RESUMO

Protein prenylation is an essential posttranslational modification and includes protein farnesylation and geranylgeranylation using farnesyl diphosphate or geranylgeranyl diphosphate as substrates, respectively. Geranylgeranyl diphosphate synthase is a branch point enzyme in the mevalonate pathway that affects the ratio of farnesyl diphosphate to geranylgeranyl diphosphate. Abnormal geranylgeranyl diphosphate synthase expression and activity can therefore disrupt the balance of farnesylation and geranylgeranylation and alter the ratio between farnesylated and geranylgeranylated proteins. This change is associated with the progression of nonalcoholic fatty liver disease (NAFLD), a condition characterized by hepatic fat overload. Of note, differential accumulation of farnesylated and geranylgeranylated proteins has been associated with differential stages of NAFLD and NAFLD-associated liver fibrosis. In this review, we summarize key aspects of protein prenylation as well as advances that have uncovered the regulation of associated metabolic patterns and signaling pathways, such as Ras GTPase signaling, involved in NAFLD progression. Additionally, we discuss unique opportunities for targeting prenylation in NAFLD/hepatocellular carcinoma with agents such as statins and bisphosphonates to improve clinical outcomes.


Assuntos
Farnesiltranstransferase/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Fosfatos de Poli-Isoprenil/metabolismo , Prenilação de Proteína , Processamento de Proteína Pós-Traducional , Animais , Progressão da Doença , Humanos , Hepatopatia Gordurosa não Alcoólica/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA