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1.
Environ Res ; 242: 117775, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38029815

RESUMEN

The development of cost-efficient biochar adsorbent with a simple preparation method is essential to constructing efficient wastewater treatment system. Here, a low-cost waste carton biochar (WCB) prepared by a simple two-step carbonization was applied in efficiently removing Rhodamine B (RhB) in aqueous environment. The maximum ability of WCB for RhB adsorption was 222 mg/g, 6 and 10 times higher than both of rice straw biochar (RSB) and broadbean shell biochar (BSB), respectively. It was mainly ascribed to the mesopore structure (3.0-20.4 nm) of WCB possessing more spatial sites compared to RSB (2.2 nm) and BSB (2.4 nm) for RhB (1.4 nm✕1.1 nm✕0.6 nm) adsorption. Furthermore, external mass transfer (EMT) controlled mass transfer resistance (MTR) of the RhB sorption process by WCB which was fitted with the Langmuir model well. Meanwhile, the adsorption process was dominated by physisorption through van der Waals forces and π-π interactions. A mixture of three dyes in river water was well removed by using WCB. This work provides a straightforward method of preparing mesoporous biochar derived from waste carton with high-adsorption capacity for dye wastewater treatment.


Asunto(s)
Carbón Orgánico , Aguas Residuales , Contaminantes Químicos del Agua , Colorantes/química , Eliminación de Residuos Líquidos/métodos , Adsorción , Contaminantes Químicos del Agua/análisis , Cinética
2.
Mikrochim Acta ; 191(5): 265, 2024 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625451

RESUMEN

Sleep deprivation (SD) is highly prevalent in the modern technological world. Emerging evidence shows that sleep deprivation is associated with oxidative stress. At the organelle level, the Golgi apparatus actively participates in the stress response. In this study, to determine whether SD and Golgi apparatus stress are correlated, we rationally designed and fabricated a novel Golgi apparatus-targeted ratiometric nanoprobe called Golgi dots for O2·- detection. This probe exhibits high sensitivity and selectivity in cells and brain slices of sleep-deprived mice. Golgi dots can be readily synthesized by coprecipitation of Golgi-F127, an amphiphilic polymer F127 modified with a Golgi apparatus targeting moiety, caffeic acid (CA), the responsive unit for O2·-, and red emissive carbon nanodots (CDs), which act as the reference signal. The fluorescence emission spectrum of the developed nanoprobe showed an intense peak at 674 nm, accompanied by a shoulder peak at 485 nm. As O2·- was gradually added, the fluorescence at 485 nm continuously increased; in contrast, the emission intensity at 674 nm assigned to the CDs remained constant, resulting in the ratiometric sensing of O2·-. The present ratiometric nanoprobe showed high selectivity for O2·- monitoring due to the specific recognition of O2·- by CA. Moreover, the Golgi dots exhibited good linearity with respect to the O2·- concentration within 5 to 40 µM, and the limit of detection (LOD) was ~ 0.13 µM. Additionally, the Golgi dots showed low cytotoxicity and an ability to target the Golgi apparatus. Inspired by these excellent properties, we then applied the Golgi dots to successfully monitor exogenous and endogenous O2·- levels within the Golgi apparatus. Importantly, with the help of Golgi dots, we determined that SD substantially elevated O2·- levels in the brain.


Asunto(s)
Encéfalo , Ácidos Cafeicos , Polietilenos , Polipropilenos , Privación de Sueño , Animales , Ratones , Aparato de Golgi , Suplementos Dietéticos
3.
Int J Mol Sci ; 25(2)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38255764

RESUMEN

Inflammatory bowel disease (IBD) is a group of intestinal inflammatory diseases characterized by chronic, recurrent, remitting, or progressive inflammation, which causes the disturbance of the homeostasis between immune cells, such as macrophages, epithelial cells, and microorganisms. Intestinal macrophages (IMs) are the largest population of macrophages in the body, and the abnormal function of IMs is an important cause of IBD. Most IMs come from the replenishment of blood monocytes, while a small part come from embryos and can self-renew. Stimulated by the intestinal inflammatory microenvironment, monocyte-derived IMs can interact with intestinal epithelial cells, intestinal fibroblasts, and intestinal flora, resulting in the increased differentiation of proinflammatory phenotypes and the decreased differentiation of anti-inflammatory phenotypes, releasing a large number of proinflammatory factors and aggravating intestinal inflammation. Based on this mechanism, inhibiting the secretion of IMs' proinflammatory factors and enhancing the differentiation of anti-inflammatory phenotypes can help alleviate intestinal inflammation and promote tissue repair. At present, the clinical medication of IBD mainly includes 5-aminosalicylic acids (5-ASAs), glucocorticoid, immunosuppressants, and TNF-α inhibitors. The general principle of treatment is to control acute attacks, alleviate the condition, reduce recurrence, and prevent complications. Most classical IBD therapies affecting IMs function in a variety of ways, such as inhibiting the inflammatory signaling pathways and inducing IM2-type macrophage differentiation. This review explores the current understanding of the involvement of IMs in the pathogenesis of IBD and their prospects as therapeutic targets.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Monocitos , Humanos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/etiología , Macrófagos , Mesalamina , Antiinflamatorios , Inflamación
4.
Appl Opt ; 62(17): 4530-4535, 2023 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-37707147

RESUMEN

Digital holography has transformative potential in measuring stacked-chip microstructures due to its noninvasive, single-shot, full-field characteristics. However, uncertainties in reconstruction distance inevitably lead to resolving blur and reconstruction distortion. Herein, we propose a phase-based reconstruction optimization method that consists of a phase-evaluation function and a structured surface-characterization model. Our proposed method involves setting a reconstruction distance range, obtaining phase information using sliced numerical reconstruction, and optimizing the reconstruction distance by finding the extreme value of the function, which identifies the focal plane of the reconstructed image. The structure of the surface topography is then characterized using the characterization model. We perform simulations of the recording, reconstruction, and characterization to verify the effectiveness of the proposed method. To further demonstrate the approach, a simple holographic recording system is constructed to measure a standard resolution target, and the measurement results are compared with a commercial instrument. The simulation and experiment demonstrate, respectively, 31.16% and 34.41% improvement in step-height characterization accuracy.

5.
Angew Chem Int Ed Engl ; 62(22): e202301382, 2023 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-36988556

RESUMEN

Developing a novel tool capable of real-time monitoring and simultaneously quantifying of both intra/extracellular chemical signals across the large-scale brain is the key bottleneck for understanding the interactions between the molecules inside and outside neurons. Here we built up a high-density intra/extracellular optophysiology platform, together with developing two probes for specific recognition of L-cysteine (Cys) and dopamine (DA), for simultaneously quantifying of both intracellular Cys and extracellular DA with high selectivity and accuracy across the brain of freely moving animals, as well as recording electrical signals. Using this powerful tool, it was found that intracellular Cys regulated extracellular DA through inducing the expression of tyrosine hydroxylase in the depressed mice brain. We also established the functional networks of Cys and DA across 32 brain regions in freely moving animals. More importantly, it was discovered that depression reduced the correlations between adjacent brain regions, which was recovered by the treatment of N-acetyl-l-cysteine.


Asunto(s)
Encéfalo , Dopamina , Ratones , Animales , Encéfalo/metabolismo , Dopamina/química , Acetilcisteína , Neuronas/metabolismo
6.
Angew Chem Int Ed Engl ; 62(23): e202302297, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36914595

RESUMEN

Microplatform with timed automata has been leveraged for guiding the preparation of molecules, whereas the requirement of handling expertise and sophisticated instrument is inevitable in combination with heterogeneous catalysis. Here we report a microfluidic-based autolab with open structures, called Put & Play Automated Microplatform (PPAM). It shows the efficient hydrogenation performance of palladium nanoparticles on the triphenylene-based covalent organic frameworks (Pd/TP-COFs) in which the π-π interactions of TP rings in the vicinity of Pd is optimized by easy change-over of catalyst and simple tuning of reactor geometries in PPAM. Using experiment/simulation of the Pd/TP-COFs coating (PCC) and mixing (PCM) across PPAM with different channel sizes, the turnover frequencies are 60 times the commonly used batch reactor, and aniline productivity of 8.8 g h-1 is achieved in 0.09 cm3 . This work will raise awareness about the benefits of the catalyst-loaded microplatform in future materials performance campaigns.

7.
Inorg Chem ; 61(47): 18979-18989, 2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36375108

RESUMEN

Charge separation and transfer are the dominating factors in achieving high activity of solar energy-based photocatalysis. Here, a plasmonic transition metal nitride, Ni3N, nanosheet was fabricated and employed as an efficient cocatalyst to couple with Cd0.9Zn0.1S (CZS) solid solution via a self-assembly method to form a novel Ni3N/CZS heterojunction with an intimate interface. On one hand, localized surface plasmon resonance of the Ni3N nanosheets endowed the fabricated Ni3N/CZS composite with a wide-spectrum light absorption capacity, even to the near-infrared range. On the other hand, Ni3N as a cocatalyst can not only effectively induce the directional electron transfer from CZS to Ni3N active sites but also enhance the surface charge separation efficiency of the Ni3N/CZS heterojunction by 4.1 times compared to that of pure CZS. Plasmonic Ni3N also provided a photothermal effect to enhance the surface temperature of the composite for boosting the catalytic reaction kinetics. As a result, under visible light irradiation, the optimal Ni3N/CZS composite exhibited simultaneous H2 generation and benzaldehyde formation rates of 35.08 and 16.44 mmol g-1 h-1, which were 9.4 and 5.9 times those of CZS, respectively; and the composite also demonstrated a strong antibacterial ability with a sterilization rate of 99.7% toward Escherichia coli. Besides that, under NIR light, plasmonic Ni3N offered extra hot electrons that can transfer back to CZS to take part in the photocatalytic reaction, leading to the Ni3N/CZS composite still having a high H2 production of 179.6 µmol g-1 h-1. This work focuses on developing and applying novel plasmonic cocatalysts in photocatalysis for achieving adjustable electron transfer and fast charge separation for extensive practical application.


Asunto(s)
Benzaldehídos , Hidrógeno , Hidrógeno/química , Catálisis , Luz
8.
Inorg Chem ; 61(34): 13608-13617, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-35980138

RESUMEN

The construction of an S-scheme charge transfer pathway is considered to be a powerful way to inhibit charge recombination and maintain photogenerated carriers with high redox capacity to meet the kinetic requirements of the carbon dioxide (CO2) photoreduction reaction. For an S-scheme heterojunction, an internal electric field (IEF) is regarded as the main driving force for accelerating the interfacial spatial transfer of photogenerated charges. Herein, we designed a TiO2 hollow-sphere (TH)-based S-scheme heterojunction for efficient CO2 photoreduction, in which WO3 nanoparticles (WP) were applied as an oxidation semiconductor to form an intimate interfacial contact with the TH. The S-scheme charge transfer mode driven by a strong IEF for the TH/WP composite was confirmed by in situ X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy. As a result, abundant photogenerated electrons with strong reducing ability would take part in the CO2 reduction reaction. The combination of surface photovoltage spectra and transient photocurrent experiments disclosed that the IEF intensity and charge separation efficiency of the fabricated TH/WP composite were nearly 16.80- and 1.42-fold higher, respectively, than those of the pure TH. Furthermore, sufficient active sites provided by the hollow-sphere structure also enhanced the kinetics of the catalytic reaction. Consequently, the optimized TH/WP composite showed a peak level of CO production of 14.20 µmol g-1 in 3 h without the addition of any sacrificial agent. This work provides insights into the kinetic studies of the S-scheme charge transfer pathway for realizing high-performance CO2 photoreduction.

9.
Environ Sci Technol ; 56(17): 12613-12624, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-35960689

RESUMEN

In situ growth of nanostructures on substrates is a strategy for designing highly efficient catalytic materials. Herein, multimetallic CuCoNi oxide nanowires are synthesized in situ on a three-dimensional nickel foam (NF) substrate (CuCoNi-NF) by a hydrothermal method and applied to peroxydisulfate (PDS) activation as immobilized catalysts. The catalytic performance of CuCoNi-NF is evaluated through the degradation of organic pollutants such as bisphenol A (BPA) and practical wastewater. The results indicate that the NF not only plays an important role as the substrate support but also serves as an internal Ni source for material fabrication. CuCoNi-NF exhibits high activity and stability during PDS activation as it mediates electron transfer from BPA to PDS. CuCoNi-NF first donates electrons to PDS to arrive at an oxidized state and subsequently deprives electrons from BPA to return to the initial state. CuCoNi-NF maintains high catalytic activity in the pH range of 5.2-9.2, adapts to a high ionic strength up to 100 mM, and resists background HCO3- and humic acid. Meanwhile, 76.6% of the total organic carbon can be removed from packaging wastewater by CuCoNi-NF-catalyzed PDS activation. This immobilized catalyst shows promising potential in wastewater treatment, well addressing the separation and recovery of conventional powdered catalysts.


Asunto(s)
Nanocables , Óxidos , Catálisis , Electrones , Níquel , Oxidación-Reducción , Aguas Residuales
10.
Proc Natl Acad Sci U S A ; 116(38): 18827-18833, 2019 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-31484775

RESUMEN

The exposed active sites of semiconductor catalysts are essential to the photocatalytic energy conversion efficiency. However, it is difficult to directly observe such active sites and understand the photogenerated electron/hole pairs' dynamics on a single catalyst particle. Here, we applied a quasi-total internal reflection fluorescence microscopy and laser-scanning confocal microscopy to identify the photocatalytic active sites at a single-molecule level and visualized the photogenerated hole-electron pair dynamics on a single TiO2 particle, the most widely used photocatalyst. The experimental results and density functional theory calculations reveal that holes and electrons tend to reach and react at the same surface sites, i.e., crystal edge/corner, within a single anatase TiO2 particle owing to the highly exposed (001) and (101) facets. The observation provides solid proof for the existence of the surface junction "edge or corner" on single TiO2 particles. These findings also offer insights into the nature of the photocatalytic active sites and imply an activity-based strategy for rationally engineering catalysts for improved photocatalysis, which can be also applied for other catalytic materials.

11.
J Virol ; 94(17)2020 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-32611755

RESUMEN

Recently, the disease of hepatitis-hydropericardium syndrome (HPS) caused by serotype 4 fowl adenovirus (FAdV-4) has spread widely and resulted in huge economic losses to the poultry industry. Although the genome of FAdV-4 has two fiber genes (fiber-1 and fiber-2), the exact role of the genes in the infection of FAdV-4 is barely known. In this study, through superinfection resistance analysis and an interfering assay, we found that fiber-1, but not fiber-2, was the key factor for directly triggering the infection of FAdV-4. The truncation analysis further revealed that both of the shaft and knob domains of fiber-1 were required for the infection. Moreover, the sera against the knob domain were able to block FAdV-4 infection, and the knob-containing fusion protein provided efficient protection against the lethal challenge of FAdV-4 in chickens. All the data demonstrated the significant roles of fiber-1 and its knob domain in directly mediating the infection of FAdV-4, which established a foundation for identifying the receptor of FAdV-4 and developing efficient vaccines against FAdV-4.IMPORTANCE Among 12 serotypes of fowl adenovirus (FAdV), FAdV-1, FAdV-4, and FAdV-10 all carry two fiber genes (i.e., fiber-1 and fiber-2), whereas other serotypes have only one. As important viral surface proteins, the fibers play vital roles in the infection and pathogenesis of FAdV. However, the importance of the fibers to the infection and pathogenesis of FAdV may be different from each other. Recent studies reveal that fiber-2 is identified as a determinant of virulence, but which fiber triggers the infection of FAdV-4 remains unknown. In this study, fiber-1 was identified as a key factor for directly mediating the infection of FAdV-4 through its shaft and knob domains, whereas fiber-2 did not play a role in triggering FAdV-4 infection. The results suggest that fiber-1 and its knob domain may serve as a target for identifying the receptor of FAdV-4 and developing efficient drugs or vaccines against FAdV-4.


Asunto(s)
Infecciones por Adenoviridae/virología , Adenoviridae/genética , Adenoviridae/metabolismo , Proteínas de la Cápside/genética , Proteínas de la Cápside/metabolismo , Enfermedades de las Aves de Corral/virología , Adenoviridae/patogenicidad , Infecciones por Adenoviridae/inmunología , Infecciones por Adenoviridae/patología , Infecciones por Adenoviridae/prevención & control , Animales , Anticuerpos Antivirales , Línea Celular , Pollos/virología , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Endogámicos BALB C , Enfermedades de las Aves de Corral/inmunología , Enfermedades de las Aves de Corral/patología , Enfermedades de las Aves de Corral/prevención & control , Dominios Proteicos , Serogrupo , Vacunas Virales/inmunología
12.
J Virol ; 94(11)2020 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-32213616

RESUMEN

Different from other subgroups of avian leukosis viruses (ALVs), ALV-J is highly pathogenic. It is the main culprit causing myeloid leukemia and hemangioma in chickens. The distinctiveness of the env gene of ALV-J, with low homology to those of other ALVs, is linked to its unique pathogenesis, but the underlying mechanism remains unclear. Previous studies show that env of ALV-J can be grouped into three species based on the tyrosine motifs in the cytoplasmic domain (CTD) of Gp37, i.e., the inhibitory, bifunctional, and active groups. To explore whether the C terminus or the tyrosine motifs in the CTD of Gp37 affect the pathogenicity of ALV-J, a set of ALV-J infectious clones containing different C termini of Gp37 or the mutants at the tyrosine sites were tested in vitro and in vivo Viral growth kinetics indicated not only that ALV-J with active env is the fastest in replication and ALV-J with inhibitory env is the lowest but also that the tyrosine sites essentially affected the replication of ALV-J. Moreover, in vivo studies demonstrated that chickens infected by ALV-J with active or bifunctional env showed higher viremia, cloacal viral shedding, and viral tissue load than those infected by ALV-J with inhibitory env Notably, the chickens infected by ALV-J with active or bifunctional env showed significant loss of body weight compared with the control chickens. Taken together, these findings reveal that the C terminus of Gp37 plays a vital role in ALV-J pathogenesis, and change from inhibitory env to bifunctional or active env increases the pathogenesis of ALV-J.IMPORTANCE ALV-J can cause severe immunosuppression and myeloid leukemia in infected chickens. However, no vaccine or antiviral drug is available against ALV-J, and the mechanism for ALV-J pathogenesis needs to be elucidated. It is generally believed that gp85 and LTR of ALV contribute to its pathogenesis. Here, we found that the C terminus and the tyrosine motifs (YxxM, ITIM, and ITAM-like) in the CTD of Gp37 of ALV-J could affect the pathogenicity of ALV-J in vitro and in vivo The pathogenicity of ALV-J with Gp37 containing ITIM only was significantly less than ALV-J with Gp37 containing both YxxM and ITIM and ALV-J with Gp37 containing both YxxM and ITAM-like. This study highlights the vital role of the C terminus of Gp37 in the pathogenesis of ALV-J and thus provides a new perspective to elucidate the interaction between ALV-J and its host and a molecular basis to develop efficient strategies against ALV-J.


Asunto(s)
Virus de la Leucosis Aviar/metabolismo , Virus de la Leucosis Aviar/patogenicidad , Leucosis Aviar/metabolismo , Enfermedades de las Aves de Corral/metabolismo , Proteínas del Envoltorio Viral/metabolismo , Secuencias de Aminoácidos , Animales , Leucosis Aviar/genética , Leucosis Aviar/patología , Virus de la Leucosis Aviar/genética , Línea Celular , Pollos , Mutación , Enfermedades de las Aves de Corral/genética , Enfermedades de las Aves de Corral/patología , Dominios Proteicos , Proteínas del Envoltorio Viral/genética
13.
Vet Res ; 52(1): 35, 2021 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-33640033

RESUMEN

Recently, the outbreaks of hydropericardium-hepatitis syndrome (HHS) caused by the highly pathogenic fowl adenovirus serotype 4 (FAdV-4) have resulted in huge economic losses to the poultry industry globally. Although several inactivated or subunit vaccines have been developed against FAdV-4, live-attenuated vaccines for FAdV-4 are rarely reported. In this study, a recombinant virus FA4-EGFP expressing EGFP-Fiber-2 fusion protein was generated by the CRISPR/Cas9 technique. Although FA4-EGFP shows slightly lower replication ability than the wild type (WT) FAdV-4, FA4-EGFP was significantly attenuated in vivo compared with the WT FAdV-4. Chickens infected with FA4-EGFP did not show any clinical signs, and all survived to 14 day post-infection (dpi), whereas those infected with FAdV-4 showed severe clinical signs with HHS and all died at 4 dpi. Besides, the inoculation of FA4-EGFP in chickens provided efficient protection against lethal challenge with FAdV-4. Compared with an inactivated vaccine, FA4-EGFP induced neutralizing antibodies with higher titers earlier. All these data not only provide a live-attenuated vaccine candidate against the highly pathogenic FAdV-4 but also give a potential insertion site for developing FAdV-4-based vaccine vectors for delivering foreign antigens.


Asunto(s)
Infecciones por Adenoviridae/veterinaria , Aviadenovirus/fisiología , Pollos , Enfermedades de las Aves de Corral/prevención & control , Vacunas Virales/administración & dosificación , Infecciones por Adenoviridae/prevención & control , Infecciones por Adenoviridae/virología , Animales , Sistemas CRISPR-Cas , Edición Génica , Genes Virales , Enfermedades de las Aves de Corral/virología , Serogrupo , Vacunas Atenuadas/administración & dosificación
14.
Environ Res ; 197: 111089, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33811867

RESUMEN

The completely biological degradation of Tetrabromobisphenol A (TBBPA) contaminant is challenging. Bio-electrochemical systems are efficient to promote electrons transfer between microbes and pollutants to improve the degradation of refractory contaminants. In particular, three-dimensional biofilm electrode reactors (3DBERs), integrating the biofilm with particle electrodes, represent a novel bio-electrochemical technology with superior treatment performances. In this study, the electroactive biofilm is cultured and acclimated on two types of particle electrodes, granular activated carbon (GAC) and granular zeolite (GZ), to degrade the target pollutant TBBPA in 3DBERs. Compared to GZ, GAC materials are more favorable for biofilm formation in terms of high specific surface area and good conductivity. The genus of Thauera is efficiently enriched on both GAC and GZ particles, whose growth is promoted by the electricity. By applying 5 V voltage, TBBPA can be removed by over 95% in 120 min whether packing GAC or GZ particle electrodes in 3DBERs. The synergy of electricity and biofilm in TBBPA degradation was more significant in GAC packed 3DBER, because the improved microbial activity by electrical stimulation accelerates debromination rate and hence the decomposition of TBBPA. Applying electricity also promotes TBBPA degradation in GZ packed 3DBER mainly due to the enhanced electrochemical effects. Roles of particle electrode materials in TBBPA removal are distinguished in this work, bringing new insights into refractory wastewater treatment by 3DBERs.


Asunto(s)
Reactores Biológicos , Bifenilos Polibrominados , Biopelículas , Electrodos
15.
Angew Chem Int Ed Engl ; 60(39): 21351-21359, 2021 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-34228388

RESUMEN

The imbalance of Cu+ and Cu2+ in the brain is closely related to neurodegenerative diseases. However, it still lacks of effective analytical methods for simultaneously determining the concentrations of Cu+ and Cu2+ . Herein, we created a novel SERS probe (CuSP) to real-time track and accurately quantify extracellular concentrations of Cu+ and Cu2+ in the live brain. The present CuSP probe demonstrated specific ability for recognition of Cu+ and Cu2+ in a dual-recognition mode. Then, a microarray consisting of 8 CuSP probes with high tempo-spatial resolution and good accuracy was constructed for tracking and simultaneously biosensing of Cu+ and Cu2+ in the cerebral cortex of living brain. Using our powerful tool, it was found that that the concentrations of Cu2+ and Cu+ were increased by ≈4.26 and ≈1.80 times upon ischemia, respectively. Three routes were first discovered for understanding the mechanisms of the increased concentrations of Cu+ and Cu2+ during ischemia.


Asunto(s)
Técnicas Biosensibles , Encéfalo/diagnóstico por imagen , Cobre/análisis , Isquemia/diagnóstico por imagen , Animales , Encéfalo/metabolismo , Cobre/metabolismo , Iones/análisis , Iones/metabolismo , Isquemia/metabolismo , Ratones , Espectrometría Raman
16.
Biophys J ; 118(12): 2894-2904, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32416081

RESUMEN

Cell migration is orchestrated by a complicated mechanochemical system. However, few cell migration models take into account the coupling between the biochemical network and mechanical factors. Here, we construct a mechanochemical cell migration model to study the cell tension effect on cell migration. Our model incorporates the interactions between Rac-GTP, Rac-GDP, F-actin, myosin, and cell tension, and it is very convenient in capturing the change of cell shape by taking the phase field approach. This model captures the characteristic features of cell polarization, cell shape change, and cell migration modes. It shows that cell tension inhibits migration ability monotonically when cells are applied with persistent external stimuli. On the other hand, if random internal noise is significant, the regulation of cell tension exerts a nonmonotonic effect on cell migration. Because the increase of cell tension hinders the formation of multiple protrusions, migration ability could be maximized at intermediate cell tension under random internal noise. These model predictions are consistent with our single-cell experiments and other experimental results.


Asunto(s)
Actinas , Polaridad Celular , Citoesqueleto de Actina , Movimiento Celular , Forma de la Célula
17.
Anal Chem ; 92(5): 3990-3997, 2020 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-32020800

RESUMEN

Mercury (Hg), as a highly harmful environmental pollutant, poses severe ecological and health risks even at low concentrations. Accurate and sensitive methods for detecting Hg2+ ions in aquatic environments are highly needed. In this work, we developed a highly sensitive fluorescence sensor for Hg2+ detection with an integrated use of biosynthetic CdSe/CdS quantum dots (QDs) and liposome carrier signal amplification. To construct such a sensor, three single-stranded DNA probes were rationally designed based on the thymine-Hg2+-thymine (T-Hg2+-T) coordination chemical principles and by taking advantage of the biocompatibility and facile-modification properties of the biosynthetic QDs. Hg2+ could be determined in a range from 0.25 to 100 nM with a detection limit of 0.01 nM, which met the requirements of environmental sample detection. The sensor also exhibited a high selectivity for Hg2+ detection in the presence of other high-level metal ions. A satisfactory capacity of the sensor for detecting environmental samples including tap water, river water, and landfill leachate was also demonstrated. This work opens up a new application scenario for biosynthetic QDs and holds a great potential for environmental monitoring applications.


Asunto(s)
Liposomas/química , Mercurio/análisis , Puntos Cuánticos/química , Espectrometría de Fluorescencia/métodos , Compuestos de Cadmio/química , ADN de Cadena Simple/química , Monitoreo del Ambiente , Agua Dulce/análisis , Concentración de Iones de Hidrógeno , Límite de Detección , Compuestos de Selenio/química , Sulfuros/química , Timina/química , Contaminantes Químicos del Agua/análisis
18.
Small ; 16(13): e1906880, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32077593

RESUMEN

It is an important issue that exposed active nitrogen atoms (e.g., edge or amino N atoms) in graphitic carbon nitride (g-C3 N4 ) could participate in ammonia (NH3 ) synthesis during the photocatalytic nitrogen reduction reaction (NRR). Herein, the experimental results in this work demonstrate that the exposed active N atoms in g-C3 N4 nanosheets can indeed be hydrogenated and contribute to NH3 synthesis during the visible-light photocatalytic NRR. However, these exposed N atoms can be firmly stabilized through forming BNC coordination by means of B-doping in g-C3 N4 nanosheets (BCN) with a B-doping content of 13.8 wt%. Moreover, the formed BNC coordination in g-C3 N4 not only effectively enhances the visible-light harvesting and suppresses the recombination of photogenerated carriers in g-C3 N4 , but also acts as the catalytic active site for N2 adsorption, activation, and hydrogenation. Consequently, the as-synthesized BCN exhibits high visible-light-driven photocatalytic NRR activity, affording an NH3 yield rate of 313.9 µmol g-1 h-1 , nearly 10 times of that for pristine g-C3 N4 . This work would be helpful for designing and developing high-efficiency metal-free NRR catalysts for visible-light-driven photocatalytic NH3 synthesis.

19.
Br J Nutr ; 124(3): 296-305, 2020 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-32216845

RESUMEN

Here, we explored the influences of dietary inulin (INU) supplementation on growth performance and intestinal health in a porcine model. Thirty-two male weaned pigs (with an average body weight of 7·10 (sd 0·20) kg) were randomly assigned to four treatments and fed with a basal diet (BD) or BD containing 2·5, 5·0 and 10·0 g/kg INU. After a 21-d trial, pigs were killed for collection of serum and intestinal tissues. We show that INU supplementation had no significant influence on the growth performance in weaned pigs. INU significantly elevated serum insulin-like growth factor-1 concentration but decreased diamine oxidase concentration (P < 0·05). Interestingly, 2·5 and 5·0 g/kg INU supplementation significantly elevated the villus height in jejunum and ileum (P < 0·05). Moreover, 2·5 and 5·0 g/kg INU supplementation also elevated the villus height to crypt depth (V:C) in the duodenum and ileum and improved the distribution and abundance of tight-junction protein zonula occludens-1 in duodenum and ileum epithelium. INU supplementation at 10·0 g/kg significantly elevated the sucrase activity in the ileum mucosa (P < 0·05). INU supplementation decreased the expression level of TNF-α but elevated the expression level of GLUT 2 and divalent metal transporter 1 in the intestinal mucosa (P < 0·05). Moreover, INU increased acetic and butyric acid concentrations in caecum (P < 0·05). Importantly, INU elevated the Lactobacillus population but decreased the Escherichia coli population in the caecum (P < 0·05). These results not only indicate a beneficial effect of INU on growth performance and intestinal barrier functions but also offer potential mechanisms behind the dietary fibre-regulated intestinal health.


Asunto(s)
Alimentación Animal/análisis , Fibras de la Dieta/farmacología , Suplementos Dietéticos , Microbioma Gastrointestinal/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Inulina/farmacología , Ácido Acético/metabolismo , Amina Oxidasa (conteniendo Cobre)/sangre , Animales , Ácido Butírico/metabolismo , Ciego/metabolismo , Duodeno/metabolismo , Escherichia coli/metabolismo , Íleon/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Yeyuno/metabolismo , Lactobacillus/metabolismo , Masculino , Modelos Animales , Porcinos , Destete
20.
J Musculoskelet Neuronal Interact ; 20(2): 265-271, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32481242

RESUMEN

OBJECTIVE: To explore the expression of miR-204 in patients with Osteoarthritis (OA) and its effect on chondrocytes. METHODS: Cartilage tissues of patients with OA, and normal cartilage tissues of patients receiving emergent traumatic amputation were collected. Polymerase chain reaction (PCR) was used to quantify the expressions of miRNAs. Chondrocytes of patients with OA were isolated, cultured, and transfected with miR-204 mimics or miR-204 inhibitor, and cell models of over-expression and knockdown of miR-204 were constructed. MTT assay, clone formation test, trypan blue staining, and TdT-mediated dUTP Nick-End Labeling (TUNEL) staining were used to detect the effect of overexpression or knockdown of miR-204 on viability, proliferation, survival rate and apoptosis of chondrocytes. RESULTS: miR-204 expression increased significantly in cartilage tissue of patients with OA. Results of MTT assay, clone formation test, and trypan blue staining showed that the over-expression of miR-204 inhibited the viability, proliferation, and survival rate, as well as promoted the apoptosis of chondrocytes. Whereas the knockdown of miR-204 improved the viability, proliferation, and survival rate of chondrocytes. CONCLUSION: The expression of miR-204 increased significantly in patients with OA and played a damaging role in chondrocytes. The knockdown of miR-204 may provide new approaches for clinical treatment of OA.


Asunto(s)
Condrocitos/metabolismo , MicroARNs/metabolismo , Osteoartritis/metabolismo , Adulto , Anciano , Apoptosis/fisiología , Cartílago Articular/metabolismo , Cartílago Articular/patología , Proliferación Celular/fisiología , Supervivencia Celular/fisiología , Células Cultivadas , Condrocitos/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/patología
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