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1.
Anal Chem ; 96(24): 9953-9960, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38850235

RESUMEN

In traditional luminol electrochemiluminescence (ECL) systems, hydrogen peroxide (H2O2) and dissolved oxygen (DO) are the commonly used coreactants to generate reactive oxygen species (ROS) for ECL emission. However, the self-decomposition of hydrogen peroxide and the limited solubility and content of oxygen in solution undoubtedly restrict the luminescence efficiency and stability of the luminol ECL system. Inspired by the ROS-mediated ECL mechanism, we pioneered hydroxide ion as an advanced luminol ECL coreactant using nickel-doped and carbon nanotube-modified tungsten oxide (Ni-WOx-CNT) as the coreactant accelerator. Owing to the excellent catalytic activity of Ni-WOx-CNT, amounts of ROS were generated from OH- at a low excitation voltage, which subsequently reacted with luminol anion radicals and triggered intense ECL signals. Experiments confirmed an impressive ECL behavior in terms of high luminescent intensity (85,563 a.u.) and super stability over 1300 consecutive tests; both are superior to those recently reported luminol-H2O2 and luminol-DO systems with smaller ECL intensities and consecutive tests less than 25 times. To validate the feasibility and versatility of the developed system in sensor, traditional three-electrodes system and closed bipolar electrodes system with various sensing strategies of direct oxidation, "gate-effect" of molecularly imprinted polymer, immune reaction, and enzyme-catalyzed reaction were proposed to monitor uric acid (UA), C-reactive protein (CRP), immunoglobulin G (IgG), and glucose (Glu). The superior sensing performances confirmed the great application potential of the developed ROS-mediated ECL system.

2.
Environ Geochem Health ; 46(4): 129, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483651

RESUMEN

The issue of potentially toxic elements (PTEs) contamination of regional soil caused by mining activities and tailings accumulation has attracted wide attention all over the world. The East Qinling is one of the three main molybdenum mines in the world, and the concentration of PTEs such as Hg, Pb and Cu in the slag is high. Quantifying the amount of PTEs contamination in soil and identifying potential sources of contamination is vital for soil environmental management. In the present investigation, the pollution levels of 8 PTEs in the Qinling molybdenum tailings intensive area were quantitatively identified. Additionally, an integrated source-risk method was adopted for resource allocation and risk assessment based on the PMF model, the ecological risk, and the health risk assessment model. The mean concentrations of Cu, Ni, Pb, Cd, Cr, Zn, As, and Hg in the 80 topsoil samples ranged from 0.80 to 13.38 times the corresponding background values; notably high levels were observed for Pb and Hg. The source partitioning results showed that PTEs were mainly affected by four pollution sources: natural and agricultural sources, coal-burning sources, combined transport and mining industry sources, and mining and smelting sources. The health risk assessment results revealed that the risks of soil PTEs for adults are acceptable, while the risks for children exceeded the limit values. The obtained results will help policymakers to obtain the sources of PTEs of tailing ponds intensive area. Moreover, it provides priorities for the governance of subsequent pollution sources and ecological restoration.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes del Suelo , Niño , Adulto , Humanos , Suelo , Metales Pesados/toxicidad , Metales Pesados/análisis , Molibdeno/análisis , Plomo/análisis , Estanques , Monitoreo del Ambiente/métodos , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Mercurio/análisis , Medición de Riesgo , China
3.
Opt Express ; 31(8): 13073-13083, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37157453

RESUMEN

Chaos generation from a novel single-loop dispersive optoelectronic oscillator (OEO) with a broadband chirped fiber Bragg grating (CFBG) is numerically and experimentally investigated. The CFBG has much broader bandwidth than the chaotic dynamics such that its dispersion effect rather than filtering effect dominates the reflection. The proposed dispersive OEO exhibits chaotic dynamics when sufficient feedback strength is guaranteed. Suppression of chaotic time-delay signature (TDS) is observed as the feedback strength increases. The TDS can be further suppressed as the amount of grating dispersion increases. Without compromising bandwidth performance, our proposed system extends the parameter space of chaos, enhances the robustness to modulator bias variation, and improves TDS suppression by at least five times comparing to the classical OEO. Experimental results qualitatively agree well with numerical simulations. In addition, the advantage of dispersive OEO is further verified by experimentally demonstrating random bit generation with tunable rate up to 160 Gbps.

4.
Opt Lett ; 48(8): 2006-2009, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-37058628

RESUMEN

Photonic time-delay reservoir computing (TDRC) using a self-injection locked semiconductor laser under optical feedback from a narrowband apodized fiber Bragg grating (AFBG) is proposed and numerically demonstrated. The narrowband AFBG suppresses the laser's relaxation oscillation and provides self-injection locking in both the weak and strong feedback regimes. By contrast, conventional optical feedback provides locking only in the weak feedback regime. The TDRC based on self-injection locking is first evaluated by the computational ability and memory capacity, then benchmarked by the time series prediction and channel equalization. Good computing performances can be achieved using both the weak and strong feedback regimes. Interestingly, the strong feedback regime broadens the usable feedback strength range and improves robustness to feedback phase variations in the benchmark tests.

5.
Artículo en Inglés | MEDLINE | ID: mdl-36790415

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) have been recognized as a potential health risk and are widespread in nature due to their intrinsic chemical stability and high recalcitrance to degradation. A taxonomic study was carried out on strain P9T, which was isolated from a PAH-degrading consortium, enriched from the mangrove sediment from Zhangzhou, PR China. The isolate was chemoheterotrophic, aerobic, Gram-stain-negative, short-rod shaped, and motile by one polar flagellum. Growth was observed at salinities from 0.5-6.0 % (optimum, 3 %), at pH 4-9 (optimum, pH 7) and at 10-41 °C (optimum, 25-30 °C). It did not synthesize bacteriochlorophyll a. Catalase and oxidase activities were positive. Acid was produced from starch, amygdalin, arbutin, cellobiose, d-fructose, maltose, d-mannitol, melezitose, melibiose, raffinose, d-ribose, sucrose, trehalose, d-xylose, aesculin ferric citrate, gentiobiose, glycogen, l-arabinose, l-rhamnose, methyl α-d-glucopyranoside, methyl ß-d-xylopyranoside, N-acetylglucosamine and salicin, and weakly positive for d-arabitol, d-galactose, lactose, turanose and glycerol. Phylogenetic analysis revealed that strain P9T fell within the clade comprising the type strains of Salipiger species and formed an independent cluster with Salipiger profundus, which was distinct from other members of the family Rhodobacteraceae. The 16S rRNA gene sequence comparisons showed that strain P9T was most closely related to Salipiger bermudensis HTCC 260T (96.7 %), and other species of the genus Salipiger (95.7-94.2 %). Strain P9T had the highest digital DNA-DNA hybridization value with S. profundus CGMCC 1.12377T (25.0 %) and the highest average nucleotide identity (ANIb and ANIm) values with S. profundus CGMCC 1.12377T(80.3 and 85.8 %, respectively). The sole respiratory quinone was quinone 10. The dominant fatty acids were C18 : 1 ω7c (61.4 %), C16 : 0 (17.5 %) and C19 : 0 ω8c cyclo (7.6 %). The G+C content of the chromosomal DNA was 65.8 mol%. In the polar lipid profile, phospholipid, phosphatidylglycerol, aminolipid, glycolipid and phosphatidylethanolamine were the major compounds. Based on the phenotypic and phylogenetic data, strain P9T represents a novel species of the genus Salipiger, for which the name Salipiger pentaromativorans sp. nov. is proposed. The type strain is P9T (=CCTCC AB 209290T=LMG 25701T=MCCC 1F01055T).


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Rhodobacteraceae , Ácidos Grasos/química , Agua de Mar/microbiología , Filogenia , ARN Ribosómico 16S/genética , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Composición de Base , Análisis de Secuencia de ADN , Fosfolípidos/química , Quinonas
6.
J Biochem Mol Toxicol ; 37(3): e23274, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36536496

RESUMEN

BACKGROUND: Circular RNA (circRNA) has been confirmed to be a key regulator for pancreatic cancer (PC) progression, but the role of circ_0000284 in PC development remains unclear. METHODS: Quantitative real-time PCR was used to measure the expression of circ_0000284, microRNA (miR)-1179, and rhophilin 2 (RHPN2). PC cell proliferation, metastasis, angiogenesis, and apoptosis were assessed by EdU assay, transwell assay, tube formation assay, and flow cytometry. Relative protein expression was determined by western blot analysis. The interaction between miR-1179 and circ_0000284 or RHPN2 was confirmed by dual-luciferase reporter assay and RNA pull-down assay. RESULTS: Circ_0000284 was significantly upregulated in PC tissues and cells, and its knockdown inhibited PC cell proliferation, migration, invasion, and angiogenesis while promoting apoptosis. MiR-1179 was downregulated in PC tissues and cells, and it could be sponged by circ_0000284. Moreover, the miR-1179 inhibitor reversed the regulation of circ_0000284 knockdown on PC cell progression. The highly expressed RHPN2 was found in PC tissues and cells, and it could be targeted by miR-1179. Also, circ_0000284 sponged miR-1179 to regulate RHPN2 expression. Overexpressed RHPN2 could reverse the regulation of circ_0000284 knockdown on PC cell progression. In addition, interference of circ_0000284 was discovered to repress PC tumor growth by regulating miR-1179/RHPN2.RHPN2. CONCLUSION: To sum up, our data confirmed that circ_0000284 facilitated PC malignant progression depending on the regulation of miR-1179/RHPN2 axis, suggesting that circ_0000284 might be a potential target for PC treatment.


Asunto(s)
MicroARNs , Neoplasias Pancreáticas , Humanos , Páncreas , Proliferación Celular , Proteínas Adaptadoras Transductoras de Señales , Neoplasias Pancreáticas
7.
Anim Biotechnol ; 34(1): 1-7, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34097574

RESUMEN

For its role in the mediation of myoblast proliferation, fibroblast growth factor receptor 1 (FGFR1) was considered a functional candidate gene for growth performance in Tibetan sheep. Via the polymerase chain reaction-restriction fragment length polymorphism (PCR-PFLP) approach, four single nucleotide polymorphisms (SNPs) including g.14752C > T (intron 1), g.45361A > G (intron 7), g.49400A > G (3'UTR region) and g.49587A > T (3'UTR region), were identified in 422 ewes. The association analysis demonstrated that individuals carrying the AA genotype of g.49400A > G had significantly greater withers height, length than those with GG genotype (p < 0.05). Individuals with genotype AA of g.49587A > T had significantly greater weight and chest circumference than those with genotype TT (p < 0.01). Additionally, the individuals with Hap1/1 diplotypes (CAAA-CAAA) were highly significantly associated with weight and chest circumference than Hap1/2 diplotypes (CAAA-CAAT) (p < 0.05). The quantitative real-time polymerase chain reaction (qPCR) analysis revealed that the FGFR1 was detectable expressed in muscle tissues within three different age stage. Remarkably higher mRNA expression was detected at fetal lamb stage as compared with adult ewes (p < 0.01). The outcome of this research confirmed that both g.49400A > G and g.49587A > T of FGFR1 were involved in growth-related traits, which may be considered to be genetic markers for improving the growth traits of Tibetan sheep.


Asunto(s)
Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos , Oveja Doméstica , Ovinos/genética , Animales , Femenino , Oveja Doméstica/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Regiones no Traducidas 3' , Fenotipo , Mutación , Genotipo , Polimorfismo de Nucleótido Simple
8.
Sensors (Basel) ; 23(7)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37050552

RESUMEN

A multi-sensor medical-image fusion technique, which integrates useful information from different single-modal images of the same tissue and provides a fused image that is more comprehensive and objective than a single-source image, is becoming an increasingly important technique in clinical diagnosis and treatment planning. The salient information in medical images often visually describes the tissue. To effectively embed salient information in the fused image, a multi-sensor medical image fusion method is proposed based on an embedding bilateral filter in least squares and salient detection via a deformed smoothness constraint. First, source images are decomposed into base and detail layers using a bilateral filter in least squares. Then, the detail layers are treated as superpositions of salient regions and background information; a fusion rule for this layer based on the deformed smoothness constraint and guided filtering was designed to successfully conserve the salient structure and detail information of the source images. A base-layer fusion rule based on modified Laplace energy and local energy is proposed to preserve the energy information of these source images. The experimental results demonstrate that the proposed method outperformed nine state-of-the-art methods in both subjective and objective quality assessments on the Harvard Medical School dataset.

9.
Int J Syst Evol Microbiol ; 72(11)2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36367518

RESUMEN

An aerobic denitrifying bacterium, designated as strain CPY4T, was isolated from activated sludge treating urban sewage under alternating aerobic/anaerobic conditions by an enrichment culture technique. Cells of strain CPY4T were Gram-stain-negative, aerobic, long rod-shaped, motile by means of single polar flagellum and capable of aerobic denitrification with citrate as the carbon source. Growth of strain CPY4T was observed at 10-45 °C (optimum, 30-35 °C), at pH 6.0-10.5 (optimum, pH 8.0-8.5) and in 0-5 % NaCl (optimum, 0-3 %; w/v). The 16S rRNA gene sequence of strain CPY4T showed the highest similarity to Zobellella denitrificans ZD1T (97.9 %), followed by Zobellella endophytica 59N8T (97.6 %), Zobellella aerophila JC2671T (97.2 %), Zobellella taiwanensis ZT1T (97.1 %) and Zobellella maritima 102-Py4T (96.3 %). Genome comparisons between CPY4T and other Zobellella species showed highest digital DNA-DNA hybridization with Z. denitrificans ZD1T (43.8 %) and highest average nucleotide identity (ANIb and ANIm) of genome nucleotide sequences with Z. denitrificans ZD1T(90.7 and 92 %, respectively). Phylogenetic analysis revealed that strain CPY4T fell within the clade comprising the type strains of Zobellella species and formed a phyletic line with them, which was distinct from other members of the family Aeromonadaceae. The sole respiratory ubiquinone was quinone 8. The predominant fatty acids (>10 % of the total fatty acids) of strain CPY4T were summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c), summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c) and C16 : 0. The genomic DNA G+C content was 62.7 mol %. In the polar lipid profile, diphosphatidylglycerol, phosphatidylglycerol, phosphatidyl ethanolamine, phospholipids and aminolipids were the major compounds. Based on the genotypic and phenotypic data, strain CPY4T represents a novel species of the genus Zobellella, for which the name Zobellella iuensis sp. nov. is proposed. The type strain is CPY4T (=JCM 34456T=CGMCC 1.18722T).


Asunto(s)
Aeromonadaceae , Aguas del Alcantarillado/microbiología , ARN Ribosómico 16S/genética , Filogenia , Composición de Base , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Ácidos Grasos/química , Análisis de Secuencia de ADN , Fosfolípidos/química , Ubiquinona/química
10.
Acta Biochim Biophys Sin (Shanghai) ; 54(10): 1518-1527, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36239354

RESUMEN

CD70 is overexpressed in a variety of solid and hematological tumors and plays a role in tumor proliferation and evasion of immune surveillance. Targeting and blocking its binding to the receptor CD27 have the potential to treat CD70-dependent tumors. To generate novel CD70 blocking agents, we screen a human CD70-immunized camel VHH phage display library and isolate two blocking nanobodies against human CD70 targeting different epitopes. Upon enrichment by three rounds of biopanning, two strategies are employed to identify CD70 blockers. One named affinity selection is used for detecting clones with CD70 binding by conventional PE-ELISA. However, no clone with a blocking effect is obtained from 188 enriched clones by this method. The alternative strategy named competitive selection is based on the inhibiting capacity of CD70-CD27 binding by enriched VHHs. By this method, two clones, Nb-2B3 and Nb-3B6, with strong blocking capacity are obtained from 20 enriched VHHs, suggesting the efficiency of this strategy. Furthermore, Nb-2B3 and Nb-3B6 specifically bind to CD70-positive SKOV3 and Raji cells at low concentrations. Meanwhile, Nb-2B3 has no competitive effect on the binding of Nb-3B6 to CD70, and vice versa, indicating that they target two different epitopes on CD70. Our data show that nanobodies Nb-2B3 and Nb-3B6 are potential attractive theranostic agents for CD70-expressing cancers.


Asunto(s)
Neoplasias , Anticuerpos de Dominio Único , Humanos , Anticuerpos de Dominio Único/farmacología , Epítopos , Biblioteca de Genes , Ensayo de Inmunoadsorción Enzimática , Ligando CD27
11.
J Am Chem Soc ; 143(6): 2545-2551, 2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33465309

RESUMEN

Pressure processing is efficient to regulate the structural and physical properties of two-dimensional (2D) halide perovskites which have been emerging for advanced photovoltaic and light-emitting applications. Increasing numbers of studies have reported pressure-induced and/or enhanced emission properties in the 2D halide perovskites. However, no research has focused on their photoresponse properties under pressure tuning. It is also unclear how structural change affects their excitonic features, which govern the optoelectronic properties of the halide perovskites. Herein, we report significantly enhanced photocurrents in the all-inorganic 2D perovskite Cs2PbI2Cl2, achieving over 3 orders of magnitude increase at the industrially achievable level of 2 GPa in comparison with its initial photocurrent. Lattice compression effectively regulates the excitonic features of Cs2PbI2Cl2, reducing the exciton binding energy considerably from 133 meV at ambient conditions to 78 meV at 2.1 GPa. Impressively, such a reduced exciton binding energy of 2D Cs2PbI2Cl2 is comparable to the values of typical 3D perovskites (MAPbBr3 and MAPbI3), facilitating the dissociating of excitons into free carriers and enhancing the photocurrent. Further pressurization leads to a layer-sliding-induced phase transition and an anomalous negative linear compression, which has not been observed so far in other halide perovskites. Our findings reveal the dramatically enhanced photocurrents in the 2D halide perovskite by regulating its excitonic features and, more broadly, provide new insights into materials design toward extraordinary properties.

12.
Artículo en Inglés | MEDLINE | ID: mdl-33492207

RESUMEN

A bisphenol A-degrading bacterium, designated as strain H4T, was isolated from surface seawater, which was sampled from the Jiulong River estuary in southeast PR China. Strain H4T is Gram-stain-negative, aerobic, short rod-shaped, lacking bacteriochlorophyll a, motile with multifibrillar stalklike fascicle structures and capable of degrading bisphenol A. Growth of strain H4T was observed at 24-45 °C (optimum, 32 °C), at pH 5.5-9 (optimum, pH 7.0) and in 0-7 % NaCl (optimum, 2 %; w/v) . The 16S rRNA gene sequence of strain H4T showed highest similarity to Croceicoccus pelagius Ery9T (98.7 %), Croceicoccus sediminis (98.3 %), Croceicoccus naphthovorans PQ-2T (98.1 %) and Croceicoccus ponticola GM-16T (97.6 %), followed by Croceicoccus marinus E4A9T (96.7 %) and Croceicoccus mobilis Ery22T (96.0 %). Phylogenetic analysis revealed that strain H4T fell within a clade comprising the type strains of Croceicoccus species and formed a phyletic line with them that was distinct from other members of the family Erythrobacteraceae. The sole respiratory quinone was quinone 10 (Q-10). The predominant fatty acids (>5 % of the total fatty acids) of strain H4T were summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c), summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c), C17 : 1 ω6c and C14 : 02-OH. The genomic DNA G+C content was 62.8 mol%. In the polar lipid profile, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, two unidentified phospholipids, two sphingoglycolipids and three unknown lipids were the major compounds. Based on the genotypic and phenotypic data, strain H4T represents a novel species of the genus Croceicoccus, for which the name Croceicoccus bisphenolivorans sp. nov. is proposed. The type strain is H4T (=DSM 102182T=MCCC1 K02301T).


Asunto(s)
Alphaproteobacteria/clasificación , Compuestos de Bencidrilo/metabolismo , Fenoles/metabolismo , Filogenia , Agua de Mar/microbiología , Alphaproteobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Estuarios , Ácidos Grasos/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/análogos & derivados , Ubiquinona/química
13.
BMC Musculoskelet Disord ; 22(1): 174, 2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33573620

RESUMEN

BACKGROUND: This study aimed to investigate the effect of abnormal Core binding factor-ß expression on proliferation, differentiation and apoptosis of chondrocytes, and elucidate the relationship between Core binding factor-ß and osteoarthritis-related markers and degenerative joint disease. METHODS: Cartilage tissues, from healthy subjects and patients with osteoarthritis, were collected for histology and expression of Core binding factor-ß, MMP-13, IL-1ß, COMP, and YKL-40. Human articular chondrocytes were cultured in vitro, and a viral vector was constructed to regulate cellular Core binding factor-ß expression. Cellular proliferation and apoptosis were observed, and osteoarthritis-related inflammatory factor expression and cartilage metabolite synthesis assayed. RESULTS: Human osteoarthritis lesions had disordered cartilage structure and cellular arrangement, and increased emptying of cartilage lacunae. Normal cell counts were significantly reduced, cartilage extracellular matrix was obviously damaged, and type II collagen expression was significantly decreased. Core binding factor-ß was highly expressed in the osteoarthritis cartilage (p < 0.001), and MMP-13, IL-1ß, COMP and YKL-40 expression were greater than found in normal cartilage (p < 0.001). Cellular proliferation in the Core binding factor-ß high-expression group was reduced and the total apoptosis rate was increased (p < 0.05), while the opposite was found in the Core binding factor-ß inhibition group (p < 0.01). Compared with normal chondrocytes, high Core binding factor-ß expression (Osteoarthritis and CBFB/pCDH groups) was associated with significantly increased MMP13, IL-1ß, COMP and YKL-40 protein expression (p < 0.01), while Core binding factor-ß inhibition (CBFB/pLKO.1 group) was associated with significantly decreased COMP, MMP13, IL-1ß and YKL-40 expression in osteoarthritis cells (p < 0.001). CONCLUSIONS: Abnormal Core binding factor-ß expression might play an upstream regulatory role in mediating abnormal chondrocyte apoptosis and the inflammatory response. On inhibiting Core binding factor-ß expression, a delay in cartilage degeneration was expected. TRIAL REGISTRATION: The study was registered for clinical trials in ChiCTR: ChiCTR1800017066 (Reg. Date-2018/7/10).


Asunto(s)
Cartílago Articular , Osteoartritis , Apoptosis , Células Cultivadas , Condrocitos , Colágeno Tipo II , Humanos , Interleucina-1beta
14.
J Cell Biochem ; 121(8-9): 3941-3951, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31696964

RESUMEN

The proliferation of hepatic progenitor cells (HPCs) is observed in reactive conditions of the liver and primary liver cancers. Ring1 as a member of polycomb-group proteins which play vital roles in carcinogenesis and stem cell self-renewal was increased in HCC patients and promoted proliferation and survival of cancer cell by degrading p53. However, the mechanisms of Ring1 driving the progression of hepatocarcinogenesis have not been elucidated. In this study, forced expression Ring1 and Ring1 siRNA lentiviral vectors were utilized to stably overexpression and silence Ring1 in HPC cell line (WB-F344), respectively. Our finding indicated that overexpression of Ring1 in HPCs promoted colony formation, cell multiplication, and invasion in vitro, conversely depletion of Ring1 repressed the biological functions of HPCs relative to controls. The expression of ß-catenin was upregulated in the HPCs with overexpression of Ring1, and the correlation analysis also showed that ß-catenin and Ring1 had a significant correlation in the liver cancer tissues and adjacent tissues. The activation of the Wnt/ß-catenin signaling pathway significantly increased the expression of liver cancer stem cells related (LCSCs)-related molecular markers CD90 and EpCAM, which led to the transformation of HPCs into LCSCs. Most importantly, the injection of HPCs with overexpressed Ring1 into the subcutaneous of nude mice leads to the formation of poorly differentiated HCC neoplasm. Our findings elucidate that overexpression of Ring1 the activated Wnt/ß-catenin signaling pathway and drove the transformation of HPCs into cancer stem cell-like cells, suggesting Ring1 has extraordinary potential in early diagnosis of HCC.

15.
Ecotoxicol Environ Saf ; 195: 110463, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32182531

RESUMEN

Microbial treatment for vanadium contamination of soils is a favorable and environment-friendly method. However, information of the resistant mechanism of the strains in soils to vanadium, especially to tetravalent vanadium [vanadium(IV)], is still limited. Herein, potential of the vanadium(IV) biosorption and biotransformation of the strains (4K1, 4K2, 4K3 and 4K4) which were capable of tolerating vanadium(IV) was determined. For biosorption, the bioadsorption and the bioabsorption of vanadium(IV) occur on the bacterial cell wall and within the cell, respectively, were taken into consideration. Comparison of the vanadium(IV) adsorbed on the bacterial cell walls and remained in the cells after sorption indicated the major bacterial vanadium(IV) sorption role of the bioadsorption which was at least one order of magnitude higher than the bioabsorption amount. Isotherm study using various isotherm models revealed a monolayer and a multilayer vanadium(IV) biosorption by 4K2 and the others (4K1, 4K3 and 4K4), respectively. Higher biosorption was observed in acidic conditions than in alkaline conditions, and the maximum biosorption was 2.41, 9.35, 7.76 and 8.44 mg g-1 observed at pH 6 for 4K1, at pH 3 for 4K2, and at pH 4 for 4K3 and 4K4, respectively. At the present experimental range of the initial vanadium(IV) concentration, optimal biosorption capacity of the bacteria was observed at the vanadium(IV) level of 100-250 mg L-1. Different biotransformation level of vanadium(IV) in soils by the stains was observed during a 28-d pot incubation of the soils mixed with the strains, which can be attributed to the discrepancy of both soil properties and bacterial species. Present study can help to fill up the gaps of the insufficient knowledge of the vanadium(IV) resistant mechanism of the strains in soils.


Asunto(s)
Bacterias/metabolismo , Contaminantes del Suelo/metabolismo , Vanadio/metabolismo , Adsorción , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Biotransformación , Óxido Ferrosoférrico , Concentración de Iones de Hidrógeno , Minería , Suelo/química , Microbiología del Suelo , Contaminantes del Suelo/toxicidad , Titanio , Vanadio/toxicidad
16.
Cytometry A ; 95(6): 683-690, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30422397

RESUMEN

Described is the new cytometric approach do detect either stimulation or a collapse of lysosomal proton pump (lysosomes rupture) combined with activation of transglutaminase 2 (TG2) during induction of apoptosis. Apoptosis of human lymphoblastoid TK6 cells was induced by combination of 2-deoxyglucose with the isoquinoline alkaloid berberine, by DNA topoisomerase I inhibitor camptothecin, its analog topotecan, topoisomerase II inhibitors etoposide or mitoxantrone, as well as by the cytotoxic anticancer ribonuclease ranpirnase (onconase). Activity of the proton pump of lysosomes was assessed by measuring entrapment and accumulation of the basic fluorochrome acridine orange (AO) resulting in its metachromatic red luminescence (F>640 ) within these organelles. Activation of TG2 was detected in the same cell subpopulation by the evidence of crosslinking of cytoplasmic proteins revealed by the increased intensity of the side light scatter (SSC) as well as following cell lysis by detergent, by its red fluorescence after staining by sulforhodamine 101. Because at low AO concentration nuclear DNA of the lysed cells was stoichiometrically stained green (F530 ) its quantity provided information on effects of the drug treatments on cell cycle in relation to activation of TG2. The data reveal that activation of lysosomal proton pump was evident in subpopulations of cells treated with 2-deoxyglucose plus berberine, topotecan, etoposide and mitoxantrone but not with ranpirnase. The collapse of lysosomal proton pump possibly reporting rupture of these organelles was observed in definite cell subpopulations after treatment with each of the studied drugs. Because regardless of the inducer of apoptosis TG2 activation invariably was correlated with lysosomes rupture it is likely that it was triggered by calcium ions or protons released from the ruptured lysosomes. This new methodological approach offers the means to investigate mechanisms and factors affecting autophagic lysosomes proton pump activity vis-à-vis TG2 activation that are common in several pathological states. © 2019 International Society for Advancement of Cytometry.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proteínas de Unión al GTP/metabolismo , Citometría de Imagen/métodos , Lisosomas/enzimología , Bombas de Protones/efectos de los fármacos , Transglutaminasas/metabolismo , Naranja de Acridina/metabolismo , Autofagosomas/efectos de los fármacos , Autofagosomas/enzimología , Ciclo Celular/efectos de los fármacos , Fluorescencia , Células HL-60 , Humanos , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Proteína Glutamina Gamma Glutamiltransferasa 2 , Bombas de Protones/metabolismo
17.
Brain Behav Immun ; 80: 825-838, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31125710

RESUMEN

Psychological stress promotes tumor progression and has a large impact on the immune system, particularly the spleen. The spleen plays an important role in tumor behavior. However, the role and mechanism of the spleen in hepatocellular carcinoma progression induced by stress is unclear. Here, we showed that the spleen plays a critical role in hepatocellular carcinoma growth induced by restraint stress. Our results demonstrated that restraint stress promoted hepatocellular carcinoma growth, changed the spleen structure, and redistributed splenic myeloid cells to tumor tissues. Interestingly, we found that splenectomy could inhibit hepatocellular carcinoma growth and prevent increases in myeloid cells and macrophages in tumor tissues in stressed mice. Restraint stress significantly elevated the concentration of norepinephrine in the spleen, serum and tumor tissues. Meanwhile, propranolol, an inhibitor of ß-adrenergic signaling, could inhibit hepatocellular carcinoma growth and prevent the redistribution of splenic myeloid cells induced by restraint stress, suggesting that restraint stress promotes hepatocellular carcinoma growth and redistributes splenic myeloid cells through ß-adrenergic signaling. Mechanistic studies revealed that restraint stress upregulated the expressions of CXCL2/CXCL3 in tumor tissues and changed the expression of CXCR2 in myeloid cells. SB225002, an inhibitor of CXCR2, could prevent the recruitment of myeloid cells in tumor tissues and inhibit tumor growth in stressed mice. Together, these data indicate that chronic restraint stress promotes hepatocellular carcinoma growth by mobilizing splenic myeloid cells to tumor tissues via activating ß-adrenergic signaling. The CXCR2-CXCL2/CXCL3 axis contributed to the recruitment of myeloid cells in tumor tissues induced by restraint stress.


Asunto(s)
Carcinoma Hepatocelular/inmunología , Bazo/inmunología , Estrés Psicológico/metabolismo , Adrenérgicos , Animales , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Proliferación Celular , Quimiocina CXCL2 , Quimiocinas CXC , Neoplasias Hepáticas/metabolismo , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Células Mieloides/inmunología , Células Mieloides/patología , Propranolol/farmacología , Receptores Adrenérgicos beta/metabolismo , Receptores de Interleucina-8B , Restricción Física , Transducción de Señal/efectos de los fármacos , Bazo/patología , Estrés Fisiológico/inmunología , Estrés Psicológico/patología
18.
J Am Chem Soc ; 140(35): 11085-11090, 2018 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-30081628

RESUMEN

The two-dimensional Ruddlesden-Popper (RP) phases are an important class of halide perovskites with versatile optoelectronic properties. So far, only organic-inorganic hybrid RP phases involving long organic spacers were reported in this class. Here, we report an all-inorganic RP phase lead halide perovskite, Cs2PbI2Cl2 (1, I4/ mmm space group; a = 5.6385(8) Å, c = 18.879(4) Å), synthesized by a solid-state method. The compound exhibits a band gap of Eg ∼ 3.04 eV and photoconductivity. We find an anomalous band gap evolution in Cs2Pb1- xSn xI2Cl2 solid solutions. Our combined density functional theory and experimental study supports the thermodynamically stable nature of 1 as a unique ordered phase in the Cs2PbX4 (X = Cl, Br, I) system. The calculations suggest that 1 is a direct bandgap semiconductor with relatively small effective carrier mass along the in-plane direction, consistent with the experimentally observed in-plane UV-light photoresponse. We also demonstrate that 1 is promising for radiation detection capable of α-particle counting. Moreover, 1 shows markedly ambient and thermal stability.

19.
Dig Dis Sci ; 63(7): 1860-1867, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29721775

RESUMEN

BACKGROUND: Hematopoietic abnormality is a common cause of cirrhotic hypersplenism (CH) complications and death; it causes serious adverse effects and is associated with bleeding, anemia, infection in CH patients. However, the underlying mechanism is unclear. AIMS: We aimed to investigate the effects of the spleen on hematopoiesis and hematopoietic stem/progenitor cells (HSPCs) in CH patients. METHODS: Eleven CH patients were enrolled to assess the effects of the spleen on HSPC functions. Hematopoietic changes were examined by flow cytometry analysis. HSPC functions were detected with colony-forming assays and in vitro cell cultures. Enzyme-linked immunosorbent assay (ELISA) was used to test the concentration of epithelial growth factor (EGF). RESULTS: The number of HSPCs was decreased in CH patients and was rescued after splenectomy. Serum from CH patients dysregulated HSPCs function, and serum from splenectomy patients restored the dysregulated HSPC function in vitro. The concentration of EGF was decreased in CH patients and was restored to normal level after splenectomy. EGF rescued the dysregulated HSPCs function in vitro. CONCLUSIONS: The spleen can regulate the functions of HSPCs in CH patients by regulating EGF signaling. EGF may be a therapeutic target for CH treatment.


Asunto(s)
Factor de Crecimiento Epidérmico/metabolismo , Hematopoyesis Extramedular , Células Madre Hematopoyéticas/metabolismo , Hiperesplenismo/etiología , Cirrosis Hepática/complicaciones , Bazo/metabolismo , Proliferación Celular , Células Cultivadas , Factor de Crecimiento Epidérmico/sangre , Femenino , Células Madre Hematopoyéticas/patología , Humanos , Hiperesplenismo/metabolismo , Hiperesplenismo/patología , Hiperesplenismo/cirugía , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad , Transducción de Señal , Bazo/patología , Bazo/cirugía , Esplenectomía , Factores de Tiempo , Resultado del Tratamiento
20.
Apoptosis ; 22(2): 229-238, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27796611

RESUMEN

Utilizing a variety of flow cytometric methods evidence was obtained indicating that a combination of the glucose analog 2-deoxy-D-glucose (2-dG) and the plant alkaloid berberine (BRB) produces synergistic effect in the induction of apoptosis in human lymphoblastoid TK6 cells. The synergistic effect is seen at concentrations of the drugs at which each of them alone shows no cytotoxicity at all. The data suggest that the combination of these drugs, which are known in terms of their overall toxicity, side effects and pharmacokinetics may be considered for further studies as chemopreventive and cancer treatment modalities. Of interest are results indicating that rapamycin, which similarly to BRB, suppresses mTOR signaling, when combined with 2-dG shows no synergistic properties. Metformin, on other hand, requires much higher concentration to show the synergy with 2-dG. Also of interest are the findings pertaining to the methodology of the present study. Specifically, dynamic assessment of cellular viability was performed by using the DRAQ7 cell exclusion fluorochrome present in cultures from 0 to 72 h. Concurrent measurement of lysosomal proton pump using acridine orange as the probe shows activation of lysosomes in the cells treated with 2-dG or BRB alone as well as with the drugs combined. Apoptosis was assessed by measuring DNA fragmentation, cell cycle, activation of caspase-3 and tissue transglutaminase (Tgase). A novel cytometric method was developed based on analysis of lysosomal (acidic vesicles) proton pump in live cells followed by cell lysis with detergent and fluorochrome labeling of proteins and DNA to analyze Tgase activation concurrently with cell cycle, in same population of cells. The data show that the cell subpopulation undergoing apoptosis has increased side (right-angle) light scatter likely due to the presence of the crosslinked (solid state) proteins, the consequence Tgase activation.


Asunto(s)
Apoptosis/efectos de los fármacos , Berberina/farmacología , Desoxiglucosa/farmacología , Transglutaminasas/genética , Apoptosis/genética , Autofagia/efectos de los fármacos , Autofagia/genética , Línea Celular , Supervivencia Celular/efectos de los fármacos , Sinergismo Farmacológico , Citometría de Flujo , Humanos , Lisosomas/efectos de los fármacos , Lisosomas/genética , Metformina/farmacología , Bombas de Protones/genética
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