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1.
Proc Natl Acad Sci U S A ; 121(24): e2404205121, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38833470

RESUMEN

The mechanical response of rubbers has been ubiquitously assumed to be only a function of the imposed strain. Using innovative X-ray measurements capturing the three-dimensional spatial volumetric strain fields, we demonstrate that rubbers and indeed many common engineering polymers undergo significant local volume changes. But remarkably, the overall specimen volume remains constant regardless of the imposed loading. This strange behavior which also leads to apparent negative local bulk moduli is due to the presence of a mobile phase within these materials. Combining X-ray tomographic observations with high-speed radiography to track the motion of the mobile phase, we have revised classical thermodynamic frameworks of rubber elasticity. The work opens broad avenues to understand not only the mechanical behavior of rubbers but a large class of widely used engineering polymers.

2.
Anal Chem ; 96(5): 1913-1921, 2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38266028

RESUMEN

2D nanosheets (NSs) have been widely used in drug-related applications. However, a comprehensive investigation into the cytotoxicity mechanism linked to the redox activity is lacking. In this study, with cytochrome c (Cyt c) as the model biospecies, the cytotoxicity of 2D NSs was evaluated systematically based on their redox effect with microfluidic techniques. The interface interaction, dissolution, and redox effect of 2D NSs on Cyt c were monitored with pulsed streaming potential (SP) measurement and capillary electrophoresis (CE). The relationship between the redox activity of 2D NSs and the function of Cyt c was evaluated in vitro with Hela cells. The results indicated that the dissolution and redox activity of 2D NSs can be simultaneously monitored with CE under weak interface interactions and at low sample volumes. Both WS2 NSs and MoS2 NSs can reduce Cyt c without significant dissolution, with reduction rates measured at 6.24 × 10-5 M for WS2 NSs and 3.76 × 10-5 M for MoS2 NSs. Furthermore, exposure to 2D NSs exhibited heightened reducibility, which prompted more pronounced alterations associated with Cyt c dysfunction, encompassing ATP synthesis, modifications in mitochondrial membrane potential, and increased reactive oxygen species production. These observations suggest a positive correlation between the redox activity of 2D NSs and their redox toxicity in Hela cells. These findings provide valuable insight into the redox properties of 2D NSs regarding cytotoxicity and offer the possibility to modify the 2D NSs to reduce their redox toxicity for clinical applications.


Asunto(s)
Citocromos c , Molibdeno , Humanos , Células HeLa , Oxidación-Reducción
3.
Anal Chem ; 96(25): 10256-10263, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38865612

RESUMEN

Assembling small molecules at liquid/solid interfaces is relatively common and contributes to many unique properties of the interface. However, such an assembling process can be dynamic depending on the concentration of the molecule and the properties of the solid and liquid themselves, which poses serious challenges on the accurate evaluation of the assembling processes. Herein, we report a convenient way for in situ and real-time monitoring of assembling-disassembling of small-molecule surfactants on the surface of microchannels using pulsed streaming potential (SP) measurement based on the variation of surface charge. With this technique, five distinctive kinetic regimes, each responsible for a characteristic molecular behavior, can be differentiated during a typical assembling-disassembling cycle. Significant difference of the assembling-disassembling process was clearly reflected for surfactants with hydrophobic tails of only a two -CH2- difference (C16TAB/C18TAB and D10DAB/D12DAB). The relative SP (Er) value is positively correlated with the molecular weight at a concentration of 0.1 mM for the same kinds of surfactants. Moreover, the assembling kinetics of D10DAB exhibits an "overshoot effect" at high concentration, which means morphology adjustment. The consequences of such assembling/disassembling of these molecules for electrophoretic separation, protein immobilization, and photocatalysis in a microchannel were investigated through dynamic characterization, which proves its potential as a tool for dynamic solid/liquid interface characterization.

4.
Small ; 20(26): e2310970, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38243848

RESUMEN

Hypergolicity is a highly desired characteristic for hybrid rocket engine-based fuels because it eliminates the need for a separate ignition system. Introducing hypergolic additives into conventional fuels through physical mixing is a feasible approach, but achieving highly reliable hypergolic ignition and energy release remains a major challenge. Here, the construction of core-shell Al@metal organic framework (MOF) heterostructures is reported as high-performance solid hypergolic propellants. Upon contact with the liquid oxidizer the uniformly distributed hypergolic MOF (Ag-MOF) shell can induce the ignition of hypergolic-inert fuel Al, resulting in Al combustion. Such a synthetic strategy is demonstrated to be favorable in hotspot generation and heat transfer relative to a simple physical mixture of Al/Ag-MOF, thus producing shorter ignition delay times and more efficient combustion. Thermal reactivity study indicated that the functionalization of the Ag-MOF shell changes the energy release process of the inner Al, which is accompanied by a thermite reaction. The synergistic effect of implantation of hypergolic MOF and high energy Al contributes to high specific impulses of 230-270 s over a wide range of oxidizer-to-fuel ratios.

5.
BJOG ; 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38853304

RESUMEN

OBJECTIVE: To evaluate the associations of plasma polybrominated diphenyl ether (PBDE) concentrations in early pregnancy with gestational weight gain (GWG). DESIGN: Prospective cohort study. SETTING: US-based, multicentre cohort of pregnant women. POPULATION: We used data from 2052 women without obesity and 397 women with obesity participating in the NICHD Fetal Growth Studies - Singleton Cohort, with first-trimester plasma PBDE concentrations and weight measurements throughout pregnancy. METHODS: We applied generalised linear models and Bayesian kernel machine regression (BKMR) to evaluate both the individual and joint associations of PBDEs with measures of GWG, adjusting for potential confounders. MAIN OUTCOME MEASURES: Total GWG (kg), total and trimester-specific GWG velocities (kg/week), and GWG categories and trajectory groups. RESULTS: Mean pre-pregnancy BMIs were 23.6 and 34.5 kg/m2 for women without and with obesity, respectively. Among women without obesity, there were no associations of PBDEs with any GWG measure. Among women with obesity, one standard deviation increase in log-transformed PBDE 47 was associated with a 1.87 kg higher total GWG (95% CI 0.39-3.35) and a 0.05 kg/week higher total GWG velocity (95% CI 0.01-0.09). Similar associations were found for PBDE 47 in BKMR among women with obesity, and PBDE 47, 99 and 100 were associated with lower odds of being in the low GWG trajectory group. CONCLUSIONS: PBDEs were not associated with GWG among individuals without obesity. Among those with obesity, only PBDE 47 showed consistent positive associations with GWG measures across multiple statistical methods. Further research is needed to validate this association and explore potential mechanisms.

6.
Environ Res ; 251(Pt 2): 118722, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38499223

RESUMEN

The key to the resource recycling of saline wastes in form of polyhydroxyalkanoates (PHA) is to enrich mixed cultures with salt tolerance and PHA synthesis ability. However, the comparison of saline sludge from different sources and the salt tolerance mechanisms of salt-tolerant PHA producers need to be clarified. In this study, three kinds of activated sludge from different salinity environments were selected as the inoculum to enrich salt-tolerant PHA producers under aerobic dynamic feeding (ADF) mode with butyric acid dominated mixed volatile fatty acid as the substrate. The maximum PHA content (PHAm) reached 0.62 ± 0.01, 0.62 ± 0.02, and 0.55 ± 0.03 g PHA/g VSS at salinity of 0.5%, 0.8%, and 1.8%, respectively. Microbial community analysis indicated that Thauera, Paracoccus, and Prosthecobacter were dominant salt-tolerant PHA producers at low salinity, Thauera, NS9_marine, and SM1A02 were dominant salt-tolerant PHA producers at high salinity. High salinity and ADF mode had synergistic effects on selection and enrichment of salt-tolerant PHA producers. Combined correlation network with redundancy analysis indicated that trehalose synthesis genes and betaine related genes had positive correlation with PHAm, while extracellular polymeric substances (EPS) content had negative correlation with PHAm. The compatible solutes accumulation and EPS secretion were the main salt tolerance mechanisms of the PHA producers. Therefore, adding compatible solutes is an effective strategy to improve PHA synthesis in saline environment.


Asunto(s)
Polihidroxialcanoatos , Salinidad , Tolerancia a la Sal , Polihidroxialcanoatos/biosíntesis , Polihidroxialcanoatos/metabolismo , Aguas del Alcantarillado/microbiología , Bacterias/metabolismo
7.
Molecules ; 29(8)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38675519

RESUMEN

The massive amount of water-soluble urea used leads to nutrient loss and environmental pollution in both water and soil. The aim of this study was to develop a novel lignin-based slow-release envelope material that has essential nitrogen and sulfur elements for plants. After the amination reaction with a hydrolysate of yak hair keratin, the coating formulation was obtained by adding different loadings (2, 5, 8, 14 wt%) of aminated lignin (AL) to 5% polyvinyl alcohol (PVA) solution. These formulations were cast into films and characterized for their structure, thermal stability, and mechanical and physicochemical properties. The results showed that the PVA-AL (8%) formulation had good physical and chemical properties in terms of water absorption and mechanical properties, and it showed good degradation in soil with 51% weight loss after 45 days. It is suitable for use as a coating material for fertilizers. Through high-pressure spraying technology, enveloped urea particles with a PVA-AL (8%) solution were obtained, which showed good morphology and slow-release performance. Compared with urea, the highest urea release was only 96.4% after 30 days, conforming to Higuchi model, Ritger-Peppas model, and second-order dynamic model. The continuous nitrogen supply of PVA-AL coated urea to Brassica napus was verified by potting experiments. Therefore, the lignin-based composite can be used as a coating material to produce a new slow-release nitrogen fertilizer for sustainable crop production.


Asunto(s)
Lignina , Alcohol Polivinílico , Urea , Lignina/química , Alcohol Polivinílico/química , Urea/química , Preparaciones de Acción Retardada/química , Fertilizantes , Polímeros/química
8.
Cell Biochem Funct ; 41(8): 1395-1402, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37842864

RESUMEN

Cervical cancer is one of the foremost common cancers in women. Lactoferrin (LF) has many biological functions, such as antitumor. This study aimed to explore the regulatory effect of bovine lactoferrin (bLF) on the proliferation and apoptosis of cervical cancer HeLa cells and to clarify the potential mechanism of action of bLF against HeLa cells. This study used CCK-8, Trypan blue staining, and colony formation assays to verify the effect of bLF on HeLa cell proliferation. Hoechst 33258 fluorescence staining, AO/EB staining, and western blotting were used to determine the effects of bLF on apoptosis and autophagy in HeLa cells. We discovered that bLF significantly reduced the proliferation of HeLa cells in a dose- and time-dependent manner compared to the control group. Furthermore, bLF primarily induced apoptosis in HeLa cells by increasing the expression of the proapoptotic proteins p53, Bax, and Cleaved-caspase-3 and downregulating the expression of the antiapoptotic protein Bcl-2. In addition, the present study also showed that bLF treatment significantly activated autophagy-related proteins LC3B-II and Beclin I and down regulated the autophagosome transporter protein p62, indicating that bLF treatment can induce autophagy in HeLa cells. After pretreatment with the autophagy inhibitor, 3-MA, which markedly found that autophagy inhibition by 3-MA reversed bLF-induced apoptosis, indicating that bLF can induce apoptosis by activating intracellular autophagy in HeLa cells. In the present study, our results support the theory of bLF significantly inhibited the proliferation of Hela cells by promoting apoptosis and reinforcing autophagy. The study will play an important role in therapying cervical cancer.


Asunto(s)
Lactoferrina , Neoplasias del Cuello Uterino , Femenino , Humanos , Apoptosis , Autofagia , Proliferación Celular , Células HeLa , Lactoferrina/farmacología , Lactoferrina/metabolismo , Neoplasias del Cuello Uterino/patología , Bovinos , Animales
9.
Molecules ; 28(15)2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37570888

RESUMEN

The emergence and fast development of carbon dots (CDs) provide an unprecedented opportunity for applications in the field of photoelectricity, but their practicability still suffers from complicated synthesis procedures and the substrate dependence of solid-state fluorescence. In this study, we design a unique microwave-assisted solid-phase synthesis route for preparing tunable fluorescent CD powders with yellow, orange, and red fluorescence (Y-CDs, O-CDs, R-CDs) by simply adjusting the mass ratio of reactants, a method which is suitable for the large-scale synthesis of CDs. The Y-/O-/R-CDs were systematically characterized using physics and spectroscopy techniques. Based on the perfect solid-state fluorescence performance of the proposed fluorescent CD powders, the Y-/O-/R-CDs were successfully applied for the construction of multi-color and white light-emitting diode devices at low cost. Furthermore, the Y-CDs displayed much higher yield and luminous efficiency than the O-CDs and R-CDs and were further used for fingerprint identification on the surfaces of glass sheets and tinfoil. In addition, the R-CD aqueous solution fluorescence is sensitive to pH, suggesting its use as a pH indicator for monitoring intracellular pH fluctuations. The proposed series of fluorescent powders composed of CDs may herald a new era in the application of optical components and criminal investigation fields.

10.
Entropy (Basel) ; 25(5)2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37238565

RESUMEN

Federated learning protects the privacy information in the data set by sharing the average gradient. However, "Deep Leakage from Gradient" (DLG) algorithm as a gradient-based feature reconstruction attack can recover privacy training data using gradients shared in federated learning, resulting in private information leakage. However, the algorithm has the disadvantages of slow model convergence and poor inverse generated images accuracy. To address these issues, a Wasserstein distance-based DLG method is proposed, named WDLG. The WDLG method uses Wasserstein distance as the training loss function achieved to improve the inverse image quality and the model convergence. The hard-to-calculate Wasserstein distance is converted to be calculated iteratively using the Lipschit condition and Kantorovich-Rubinstein duality. Theoretical analysis proves the differentiability and continuity of Wasserstein distance. Finally, experiment results show that the WDLG algorithm is superior to DLG in training speed and inversion image quality. At the same time, we prove through the experiments that differential privacy can be used for disturbance protection, which provides some ideas for the development of a deep learning framework to protect privacy.

11.
Entropy (Basel) ; 25(12)2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38136487

RESUMEN

Deep learning is one of the most exciting and promising techniques in the field of artificial intelligence (AI), which drives AI applications to be more intelligent and comprehensive. However, existing deep learning techniques usually require a large amount of expensive labeled data, which limit the application and development of deep learning techniques, and thus it is imperative to study unsupervised machine learning. The learning of deep representations by mutual information estimation and maximization (Deep InfoMax or DIM) method has achieved unprecedented results in the field of unsupervised learning. However, in the DIM method, to restrict the encoder to learn more normalized feature representations, an adversarial network learning method is used to make the encoder output consistent with a priori positively distributed data. As we know, the model training of the adversarial network learning method is difficult to converge, because there is a logarithmic function in the loss function of the cross-entropy measure, and the gradient of the model parameters is susceptible to the "gradient explosion" or "gradient disappearance" phenomena, which makes the training of the DIM method extremely unstable. In this regard, we propose a Wasserstein distance-based DIM method to solve the stability problem of model training, and our method is called the WDIM. Subsequently, the training stability of the WDIM method and the classification ability of unsupervised learning are verified on the CIFAR10, CIFAR100, and STL10 datasets. The experiments show that our proposed WDIM method is more stable to parameter updates, has faster model convergence, and at the same time, has almost the same accuracy as the DIM method on the classification task of unsupervised learning. Finally, we also propose a reflection of future research for the WDIM method, aiming to provide a research idea and direction for solving the image classification task with unsupervised learning.

12.
Opt Express ; 30(15): 26581-26596, 2022 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-36236846

RESUMEN

Aspheric cylindrical lenses, including fast axis collimators (FACs), are commonly used to collimate laser beams in the fast axis direction. Precision glass molding (PGM) is applied in the production of these optical lenses due to its high accuracy and efficiency. However, the profile errors and surface topography transferred from the mold reduce the optical performance of aspheric cylindrical lenses. In this paper, the surface errors of a FAC fabricated by combining ultraprecision diamond cutting and precision glass molding are analyzed. An optical simulation model is then established to qualitatively analyze the effects of tool marks on the optical defects, and the numerical calculations are carried out to determine the relative intensity distribution of light spots. Experiments are conducted to verify the theoretical results, which prove that the tool marks cause diffractive fringes and that the geometric parameters of the tool marks that are caused by cutting conditions affect the distribution of the fringe line defects. Finally, the critical conditions to eliminate diffractive fringes and improve the optical performance of the FAC are determined based on the experimental results.

13.
Arch Biochem Biophys ; 731: 109448, 2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-36306919

RESUMEN

Alzheimer's disease (AD), a common neurodegenerative disease, is characterised by the deposition of amyloid-ß (Aß) plaques and neurofibrillary tangles. An increasing number of studies have demonstrated that Aß causes neuronal damage and mitochondrial dysfunction. Herein, we evaluated the neuroprotective effect of sodium butyrate (NaB) against Aß induced neurotoxicity in PC12 cells. The results revealed that 3 mM of NaB promoted the expression of angiotensin-converting enzyme and brain-derived neurotrophic factor, which exert a neuroprotective effect by activating G protein-coupled receptors. Moreover, NaB could significantly improve mitochondrial dysfunction caused by Aß. In conclusion, NaB protected PC12 cells from Aß-induced cell damage, highlighting the potential of NaB in AD treatment.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Fármacos Neuroprotectores , Animales , Ratas , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/toxicidad , Péptidos beta-Amiloides/metabolismo , Antioxidantes/metabolismo , Apoptosis , Ácido Butírico/farmacología , Supervivencia Celular , Potencial de la Membrana Mitocondrial , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Células PC12 , Fragmentos de Péptidos/toxicidad , Fragmentos de Péptidos/metabolismo
14.
Cell Mol Biol (Noisy-le-grand) ; 67(6): 291-297, 2022 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-35818184

RESUMEN

Methotrexate is mainly used to treat diseases such as rheumatoid arthritis (RA), but its potential for nephrotoxicity has always been a significant concern on the use of this medication. This study aimed to determine the rate of renal fibrosis using transient elastography and its relationship with cumulative dose and duration of drug use in patients with rheumatoid arthritis treated with methotrexate. TGFß gene expression was also assessed for further evaluation. Patients with rheumatoid arthritis who received methotrexate for more than six months were included. Renal fibrosis was determined by measuring the stiffness of the kidney by elastography (FiberScan Device). RA patients were divided into two groups based on kidney stiffness measurement with and without renal fibrosis, and demographic, clinical, and biochemical parameters were compared to investigate the relationship between cumulative dose and duration of methotrexate treatment and renal fibrosis. Also, in this study, 50 controls (healthy people) and 50 cases (RA patients) were used to evaluate the expression of the TGFß gene by real-time PCR method. The existence of kidney fibrosis was observed in 10 patients. There was no significant relationship between renal fibrosis and the cumulative dose (P = 0.21) and duration of methotrexate (P = 0.30). Multivariate regression analysis showed that the chances of developing renal fibrosis in patients increase with increasing serum ALT levels (P = 0.01). The results of the TGFß gene expression showed that the expression of this gene in the group of RA patients with fibrosis was higher than the control group (healthy people) and the group of RA patients without fibrosis (P <0.01). These results showed that evaluation of renal fibrosis by elastography method is recommended for scanning RA patients while they are being treated with methotrexate, which is also confirmed by the results of the fibrosis-related-gene expression.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Diagnóstico por Imagen de Elasticidad , Enfermedades Renales , Antirreumáticos/efectos adversos , Artritis Reumatoide/inducido químicamente , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/genética , Fibrosis , Expresión Génica , Humanos , Enfermedades Renales/inducido químicamente , Enfermedades Renales/diagnóstico por imagen , Enfermedades Renales/genética , Cirrosis Hepática/tratamiento farmacológico , Metotrexato/efectos adversos , Factor de Crecimiento Transformador beta/genética
15.
Int J Mol Sci ; 23(10)2022 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-35628248

RESUMEN

JAK3 differs from other JAK family members in terms of tissue distribution and functional properties, making it a promising target for autoimmune disease treatment. However, due to the high homology of these family members, targeting JAK3 selectively is difficult. As a result, exploiting small changes or selectively boosting affinity within the ATP binding region to produce new tailored inhibitors of JAK3 is extremely beneficial. PubChem CID 137321159 was used as the lead inhibitor in this study to preserve the characteristic structure and to collocate it with the redesigned new parent core structure, from which a series of 1,7-dihydro-dipyrrolo [2,3-b:3',2'-e] pyridine derivatives were obtained using the backbone growth method. From the proposed compounds, 14 inhibitors of JAK3 were found based on the docking scoring evaluation. The RMSD and MM/PBSA methods of molecular dynamics simulations were also used to confirm the stable nature of this series of complex systems, and the weak protein−ligand interactions during the dynamics were graphically evaluated and further investigated. The results demonstrated that the new parent core structure fully occupied the hydrophobic cavity, enhanced the interactions of residues LEU828, VAL836, LYS855, GLU903, LEU905 and LEU956, and maintained the structural stability. Apart from this, the results of the analysis show that the binding efficiency of the designed inhibitors of JAK3 is mainly achieved by electrostatic and VDW interactions and the order of the binding free energy with JAK3 is: 8 (−70.286 kJ/mol) > 11 (−64.523 kJ/mol) > 6 (−51.225 kJ/mol) > 17 (−42.822 kJ/mol) > 10 (−40.975 kJ/mol) > 19 (−39.754 kJ/mol). This study may provide a valuable reference for the discovery of novel JAK3 inhibitors for those patients with immune diseases.


Asunto(s)
Enfermedades Autoinmunes , Janus Quinasa 3 , Inhibidores de Proteínas Quinasas , Piridinas , Diseño de Fármacos , Humanos , Janus Quinasa 3/antagonistas & inhibidores , Janus Quinasa 3/química , Janus Quinasa 3/metabolismo , Simulación de Dinámica Molecular , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/química , Piridinas/farmacología
16.
Molecules ; 27(16)2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-36014529

RESUMEN

The abuse of agricultural antibiotics has led to the emergence of drug-resistant phytopathogens. Rifampicin and streptomycin and streptomycin resistance Pectobacterium carotovorum subsp. carotovorum (PccS1) was obtained from pathological plants in a previous experiment. Rheum tanguticum, derived from the Chinese plateau area, exhibits excellent antibacterial activity against PccS1, yet the action mode has not been fully understood. In present text, the cell wall integrity of the PccS1 was tested by the variation of the cellular proteins, SDS polyacrylamide gel electrophoresis (SDS-PAGE), scanning electron microscopy (SEM) and Fourier transform infrared spectrophotometer (FTIR) characteristics. Label-free quantitative proteomics was further used to identify the DEPs in the pathogen response to treatment with Rheum tanguticum Maxim. ex Balf. extract (abbreviated as RTMBE). Based on the bioinformatics analysis of these different expressed proteins (DEPs), RTMBE mainly inhibited some key protein expressions of beta-Lactam resistance, a two-component system and phosphotransferase system. Most of these membrane proteins were extraordinarily suppressed, which was also consistent with the morphological tests. In addition, from the downregulated flagellar motility related proteins, it was also speculated that RTMBE played an essential antibacterial role by affecting the swimming motility of the cells. The results indicated that Rheum tanguticum can be used to attenuate the virulence of the drug-resistant phytopathogenic bacteria.


Asunto(s)
Pectobacterium carotovorum , Rheum , Antibacterianos/metabolismo , Antibacterianos/farmacología , Pared Celular/metabolismo , Pectobacterium , Pectobacterium carotovorum/fisiología , Estreptomicina
17.
Int J Mol Sci ; 22(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33668885

RESUMEN

Lysosomal membrane permeabilization (LMP) has been proposed to precede nanoparticle-induced macrophage injury and NLRP3 inflammasome activation; however, the underlying mechanism(s) of LMP is unknown. We propose that nanoparticle-induced lysosomal hyperpolarization triggers LMP. In this study, a rapid non-invasive method was used to measure changes in lysosomal membrane potential of murine alveolar macrophages (AM) in response to a series of nanoparticles (ZnO, TiO2, and CeO2). Crystalline SiO2 (micron-sized) was used as a positive control. Changes in cytosolic potassium were measured using Asante potassium green 2. The results demonstrated that ZnO or SiO2 hyperpolarized the lysosomal membrane and decreased cytosolic potassium, suggesting increased lysosome permeability to potassium. Time-course experiments revealed that lysosomal hyperpolarization was an early event leading to LMP, NLRP3 activation, and cell death. In contrast, TiO2- or valinomycin-treated AM did not cause LMP unless high doses led to lysosomal hyperpolarization. Neither lysosomal hyperpolarization nor LMP was observed in CeO2-treated AM. These results suggested that a threshold of lysosomal membrane potential must be exceeded to cause LMP. Furthermore, inhibition of lysosomal hyperpolarization with Bafilomycin A1 blocked LMP and NLRP3 activation, suggesting a causal relation between lysosomal hyperpolarization and LMP.


Asunto(s)
Membranas Intracelulares/fisiología , Lisosomas/metabolismo , Potenciales de la Membrana/fisiología , Nanopartículas/toxicidad , Animales , Muerte Celular/efectos de los fármacos , Citosol/metabolismo , Femenino , Concentración de Iones de Hidrógeno , Inflamasomas/metabolismo , Membranas Intracelulares/efectos de los fármacos , Lisosomas/efectos de los fármacos , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Masculino , Potenciales de la Membrana/efectos de los fármacos , Ratones Endogámicos C57BL , Modelos Biológicos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Permeabilidad , Potasio/metabolismo , Reproducibilidad de los Resultados , Dióxido de Silicio/toxicidad
18.
Environ Health ; 19(1): 45, 2020 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-32345324

RESUMEN

BACKGROUND: Subfertile women have higher risk of glucose intolerance during pregnancy. Studies suggest associations between several endocrine disrupting chemicals (EDCs) and pregnancy glucose levels. However, the association between benzophenone-3 (BP-3), an EDC widely found in sunscreen, and pregnancy glucose levels remains unclear. We aimed to assess the association between perinatal exposures to BP-3 and pregnancy glucose levels in subfertile women. METHODS: We evaluated 217 women from a prospective cohort based at a fertility clinic who had urinary BP-3 concentrations measured during 3-month preconception, first and/or second trimesters, and blood glucose measured at glucose load tests (GLTs) during late pregnancy. Multivariable linear and logistic regression models were used to assess associations between time-specific BP-3 in quartiles (Q1 - Q4) and mean glucose levels, as well as odds of abnormal GLT (glucose level ≥ 140 mg/dL), adjusting for potential confounders. Effect modification was assessed by age, season, BMI, infertility diagnosis, sex of fetus (es) and physical activity. RESULTS: Women with higher first trimester BP-3 concentrations had lower mean glucose levels [mean glucose (95% CI) for Q4 vs Q1 = 103.4 (95.0, 112.5) vs. 114.6 (105.8, 124.2) mg/dL]. Women with higher second trimester BP-3 concentrations had lower odds of abnormal GLT [OR (95% CI) for Q3 vs. Q1 = 0.12 (0.01, 0.94)]. The associations between BP-3 and glucose levels were modified by several factors: women with female-factor infertility, urine collected during summer, older age, lower BMI, or carried female fetus (es) had the strongest inverse associations between BP-3 and glucose levels, while no associations were observed in the remaining subgroups. CONCLUSIONS: Time-specific inverse associations between BP-3 and pregnancy glucose levels existed in subfertile women, and especially among certain subgroups of this high-risk-population.


Asunto(s)
Benzofenonas/orina , Glucemia/metabolismo , Índice de Masa Corporal , Ejercicio Físico , Feto/química , Infertilidad/diagnóstico , Exposición Materna , Adulto , Factores de Edad , Boston , Femenino , Clínicas de Fertilidad , Humanos , Persona de Mediana Edad , Embarazo , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Estaciones del Año , Factores Sexuales , Adulto Joven
19.
Chemistry ; 24(29): 7312-7329, 2018 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-29293284

RESUMEN

Carbon based supercapacitors (CSCs), with high output power and long lifespan, are considered as promising power sources for modern electronic devices. The rush to find new approaches for optimizing their electrochemical behaviors is still vibrant, and particularly, widespread enthusiasm was focused on improving the energy density of CSCs through improving the specific capacitance and expanding the operating voltage. In this regard, this article provides a brief review about recent progress and new understanding about the assembly of CSCs with high energy density. Novel applied strategies were highlighted and discussed from the aspects of electrolyte, electrodes, and device modulation. Dynamic and mechanism factors associated with the energy storage process of CSCs are particularly emphasized. Finally, the opportunities and challenges are elaborated in the hope of guiding the promising direction for the design of high-energy CSCs.

20.
Int Heart J ; 59(5): 1086-1095, 2018 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-30158376

RESUMEN

Atherosclerosis is one of the most prevalent and important cardiac diseases, involving the heart and brain. This study aimed to explore the impacts of lncRNA Divergent to GSC induced by TGF-b family signaling (DIGIT) on vascular endothelial cells tube-formation capacity so as to reveal the potentials of DIGIT in atherosclerosis therapy. DIGIT expression in human microvascular endothelial HMEC-1 cells was silenced by transfection with shRNAs-targeted DIGIT. The effects of DIGIT silence on cell viability, migration, apoptosis, and tube formation were then assessed. Additionally, the cross-regulation between DIGIT and miR-134, and between miR-134 and Bmi-1 was detected to further reveal through which mechanism (s) DIGIT mediated HMEC-1 cells. The results showed that DIGIT silence significantly reduced cell viability, migration, tube-like structures formation, and induced apoptosis in HMEC-1 cells. DIGIT worked as a sponge for miR-134, and the anti-growth, anti-migratory, and anti-tube-formation functions of DIGIT silence on HMEC-1 cells were abolished by miR-134 suppression. Bmi-1 was a target of miR-134, and Bmi-1 upregulation abolished miR-134 overexpression-diminished cell growth, migration, and tube formation of HMEC-1 cells. Furthermore, Bmi-1 upregulation activated PI3K/AKT and Notch signaling pathways. In conclusion, our study demonstrated that lncRNA DIGIT accelerated tube formation of vascular endothelial cells through sponging miR-134. Our findings suggest that DIGIT and miR-134 may be promising molecular targets for atherosclerosis therapy.


Asunto(s)
Células Endoteliales/metabolismo , MicroARNs/genética , Complejo Represivo Polycomb 1/genética , ARN Largo no Codificante/genética , Apoptosis/genética , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/metabolismo , Movimiento Celular/genética , Proliferación Celular/genética , Supervivencia Celular/genética , Células Endoteliales/patología , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal/genética , Regulación hacia Arriba/genética
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