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1.
Phys Rev Lett ; 132(8): 080201, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38457732

RESUMEN

Entanglement in bipartite systems has been applied to generate secure random numbers, which are playing an important role in cryptography or scientific numerical simulations. Here, we propose to use multipartite entanglement distributed between trusted and untrusted parties for generating randomness of arbitrary dimensional systems. We show that the distributed structure of several parties leads to additional protection against possible attacks by an eavesdropper, resulting in more secure randomness generated than in the corresponding bipartite scenario. Especially, randomness can be certified in the group of untrusted parties, even when there is no randomness in either of them individually. We prove that the necessary and sufficient resource for quantum randomness in this scenario is multipartite quantum steering when each untrusted party has a choice between only two measurements. However, the sufficiency no longer holds with more measurement settings. Finally, we apply our analysis to some experimentally realized states and show that more randomness can be extracted compared with the existing analysis.

2.
Phys Rev Lett ; 131(20): 200202, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-38039483

RESUMEN

The geometric phase is a fundamental quantity characterizing the holonomic feature of quantum systems. It is well known that the evolution operator of a quantum system undergoing a cyclic evolution can be simply written as the product of holonomic and dynamical components for the three special cases concerning the Berry phase, adiabatic non-Abelian geometric phase, and nonadiabatic Abelian geometric phase. However, for the most general case concerning the nonadiabatic non-Abelian geometric phase, how to separate the evolution operator into holonomic and dynamical components is a long-standing open problem. In this Letter, we solve this open problem. We show that the evolution operator of a quantum system can always be separated into the product of holonomy and dynamic operators. Based on it, we further derive a matrix representation of this separation formula for cyclic evolution, and give a necessary and sufficient condition for a general evolution being purely holonomic. Our finding is not only of theoretical interest itself, but also of vital importance for the application of quantum holonomy. It unifies the representations of all four types of evolution concerning the adiabatic/nonadiabatic Abelian/non-Abelian geometric phase, and provides a general approach to realizing purely holonomic evolution.

3.
Phys Rev Lett ; 131(9): 090201, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37721810

RESUMEN

The fact that quantum mechanics predicts stronger correlations than classical physics is an essential cornerstone of quantum information processing. Indeed, these quantum correlations are a valuable resource for various tasks, such as quantum key distribution or quantum teleportation, but characterizing these correlations in an experimental setting is a formidable task, especially in scenarios where no shared reference frames are available. By definition, quantum correlations are reference-frame independent, i.e., invariant under local transformations; this physically motivated invariance implies, however, a dedicated mathematical structure and, therefore, constitutes a roadblock for an efficient analysis of these correlations in experiments. Here we provide a method to directly measure any locally invariant property of quantum states using locally randomized measurements, and we present a detailed toolbox to analyze these correlations for two quantum bits. We implement these methods experimentally using pairs of entangled photons, characterizing their usefulness for quantum teleportation and their potential to display quantum nonlocality in its simplest form. Our results can be applied to various quantum computing platforms, allowing simple analysis of correlations between arbitrary distant qubits in the architecture.

4.
Pak J Med Sci ; 39(2): 485-490, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36950397

RESUMEN

Objective: To evaluate the effect of butylphthalide combined with oxiracetam on cognitive function, intellectual recovery and serum inflammatory factors in patients with cognitive impairment after cerebral infarction. Methods: This is a Clinical comparative study. A total of 80 patients with cognitive impairment after cerebral infarction who visited Renmin Hospital, Hubei University of Medicine from January 2020 to January 2022 were enrolled and randomly divided into two groups. Patients in the control group were treated with oral oxiracetam combined with routine treatment. Patients in the study group were given butylphthalide combined with oxiracetam on the basis of routine treatment. Compare the clinical effect, cognitive function and intellectual recovery, inflammatory factor level changes, CBV, CBF, MTT and other cerebral blood flow perfusion indicators, as well as post-treatment incidence of adverse drug reactions in the two groups of patients. Results: The efficacy of the study group was significantly higher than that of the control group (p=0.03). After treatment, the levels of CBV and CBF in the study group were higher than those in the control group, the levels of TNF-α, CRP and IL-6 were significantly lower than those of the control group, while MTT was shorter than that in the control group, with statistically significant difference (p=0.00). Furthermore, there was a statistically significant difference that the MMSE score and MOCA score of the study group were higher than those of the control group (p=0.00). Conclusion: Butylphthalide combined with oxiracetam has an obvious curative effect in the treatment of patients with cognitive impairment after cerebral infarction. It is a safe and effective therapeutic option that can significantly recover cognitive function and intelligence, improve cerebral blood flow perfusion and reduce inflammatory factors, without an obvious increase in adverse reactions.

5.
Anal Chem ; 93(2): 1200-1208, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33301293

RESUMEN

Engineered nanopipette tools have recently emerged as a powerful approach for electrochemical nanosensing, which has major implications in both fundamental biological research and biomedical applications. Herein, we describe a generic method of target-triggered assembly of aptamers in a nanopipette for nanosensing, which is exemplified by sensitive and rapid electrochemical single-cell analysis of adenosine triphosphate (ATP), a ubiquitous energy source in life and important signaling molecules in many physiological processes. Specifically, a layer of thiolated aptamers is immobilized onto a Au-coated interior wall of a nanopipette tip. With backfilled pairing aptamers, the engineered nanopipette is then used for probing intracellular ATP via the ATP-dependent linkage of the split aptamers. Due to the higher surface charge density from the aptamer assembly, the nanosensor would exhibit an enhanced rectification signal. Besides, this ATP-responsive nanopipette tool possesses excellent selectivity and stability as well as high recyclability. This work provides a practical single-cell nanosensor capable of intracellular ATP analysis. More generally, integrated with other split recognition elements, the proposed mechanism could serve as a viable basis for addressing many other important biological species.


Asunto(s)
Adenosina Trifosfato/análisis , Aptámeros de Nucleótidos/química , Técnicas Biosensibles , Técnicas Electroquímicas , Análisis de la Célula Individual , Células Cultivadas , Oro/química , Humanos
6.
Small ; 17(26): e2100503, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34101356

RESUMEN

Though significant advances are made in the arena of single-cell electroanalysis, quantification of intracellular amino acids of human cells remains unsolved. Exemplified by l-histidine (l-His), this issue is addressed by a practical electrochemical nanotool synergizing the highly accessible nanopipette with commercially available synthetic DNAzyme. The fabricated nanotools are screened before operation of a single-use manner, and the l-His-provoked cleavage of the DNA molecules can be sensibly transduced by the ionic current rectification response, the intrinsic property of nanopipette governed by its interior surface charges. Regional distribution of cytosolic l-His level in human cells is electrochemically quantified for the first time, and time-dependent drug treatment effects are further revealed. This work unveils the possibility of electrochemistry for quantification of cytosolic amino acids of a spatial- and time-based manner and ultimately enables a better understanding of amino acid-involved events in living cells.


Asunto(s)
Aminoácidos , ADN Catalítico , ADN , Histidina , Humanos
7.
Phys Rev Lett ; 126(14): 140503, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33891460

RESUMEN

A typical concept in quantum state analysis is based on the idea that states in the vicinity of some pure entangled state share the same properties, implying that states with a high fidelity must be entangled. States whose entanglement can be detected in this way are also called faithful. We prove a structural result on the corresponding fidelity-based entanglement witnesses, resulting in a simple condition for faithfulness of a two-party state. For the simplest case of two qubits faithfulness can directly be decided and for higher dimensions accurate analytical criteria are given. Finally, our results show that faithful entanglement is, in a certain sense, useful entanglement; moreover, they establish connections to computational complexity and simplify several results in entanglement theory.

8.
Phys Rev Lett ; 127(6): 060504, 2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34420346

RESUMEN

For the certification and benchmarking of medium-size quantum devices, efficient methods to characterize entanglement are needed. In this context, it has been shown that locally randomized measurements on a multiparticle quantum system can be used to obtain valuable information on the so-called moments of the partially transposed quantum state. This allows one to infer some separability properties of a state, but how to use the given information in an optimal and systematic manner has yet to be determined. We propose two general entanglement detection methods based on the moments of the partially transposed density matrix. The first method is based on the Hankel matrices and provides a family of entanglement criteria, of which the lowest order reduces to the known p_{3}-positive-partial-transpose criterion proposed in A. Elben et al. [Phys. Rev. Lett. 125, 200501 (2020)PRLTAO0031-900710.1103/PhysRevLett.125.200501]. The second method is optimal and gives necessary and sufficient conditions for entanglement based on some moments of the partially transposed density matrix.

9.
Anal Chem ; 92(3): 2722-2730, 2020 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-31916755

RESUMEN

Microfluidic paper analytical devices (µPADs) are smart and accessible substituents to traditional counterparts in point-of-care tests (POCT), which exploited delicate control over passive fluid in microscale for rich functions. In this work, we are extending such control by introducing novel ways to generate 1D and 2D gradients on µPADs. It is achieved by using paper-capillary-based serial sampling. The paper capillary is composed of a concaved paper channel sealed with tape, with test pads properly distributed aside. In such a structure, the liquid can not only quickly and automatically flow along the capillary but also be continuously consumed by the peripheral test pads. Thus, when we do serial sampling, an abnormal liquid chasing effect can be observed, where the later liquid sample chases and surpasses the earlier parts in the paper capillary, leading to reversely ordered sample distribution compared with that in a typical glass capillary. This specialty allows for fast, ordered, and tunable sequential sampling and enables efficient generation of 1D and 2D concentration gradient with one, two, and even three components on µPADs. Besides, we verified the applicability of this technique for arrayed assays, including 1D serial dilution-based metal ion colorimetry and a 2D bacterial antibiotic susceptibility test for synergic effect evaluations, which paves the way for high-throughput sample analysis and information-rich condition screening on µPADs.

10.
Phys Rev Lett ; 122(13): 130404, 2019 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-31012612

RESUMEN

Resource theories can be used to formalize the quantification and manipulation of resources in quantum information processing such as entanglement, asymmetry and coherence of quantum states, and incompatibility of quantum measurements. Given a certain state or measurement, one can ask whether there is a task in which it performs better than any resourceless state or measurement. Using conic programming, we prove that any general robustness measure (with respect to a convex set of free states or measurements) can be seen as a quantifier of such outperformance in some discrimination task. We apply the technique to various examples, e.g., joint measurability, positive operator valued measures simulable by projective measurements, and state assemblages preparable with a given Schmidt number.

11.
Int J Syst Evol Microbiol ; 69(5): 1459-1464, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30882295

RESUMEN

A novel Gram-stain-negative, motile, rod-shaped (0.4-0.5×1.0-2.0 µm) strain with one polar flagellum, designated SY39T, was isolated from seawater in Sanya, China. Strain SY39T was able to grow at 15-40 °C (optimum, 35-37 °C), pH 6.5-8.5 (pH 8.0) and 0.5-6.0 % (w/v) NaCl (3.5 %). Chemotaxonomic analysis showed that the isoprenoid quinones were Q-8 (88.6 %) and Q-7 (11.4 %). The dominant fatty acids were C16 : 0 and summed feature 3 (C16 : 1ω7c/C16 : 1ω6c). The polar lipids of strain SY39T consisted of diphosphatidyglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unknown phosphoglycolipid, one unknown glycolipid and two unknown aminophosphoglycolipids. The DNA G+C content of the genomic DNA was 66.5 mol%. The phylogenetic analysis of 16S rRNA gene sequences showed that strain SY39T belongs to the genus Azoarcus with similarity ranging from 92.3 to 95.2 %. Based on the phenotypic, chemotaxonomic and phylogenetic features, strain SY39T is concluded to represent a novel species of the genus Azoarcus, for which the name Azoarcus pumilus sp. nov. is proposed. The type strain is SY39T (=KCTC 62157T=MCCC 1K03430T).


Asunto(s)
Azoarcus/clasificación , Filogenia , Agua de Mar/microbiología , Azoarcus/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Glucolípidos/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química
12.
Int J Syst Evol Microbiol ; 69(5): 1490-1495, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30893030

RESUMEN

A Gram-stain-negative, motile, aerobic, rod-shaped bacterium with flagella, designated ZX-21T, was isolated from surface seawater of the East Sea in Zhoushan, China. Growth of strain ZX-21T was observed at 10--35 o°C (optimum, 30 °C), at pH 6.0-8.5 (pHoptimum 6.5-7.0) and in the presence of 0.5-8 % (w/v) NaCl (optimum 3-4 %). It was positive for oxidase and catalase activity. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZX-21T constituted an independent lineage within the family Spongiibacteraceae and was most closely related to Zhongshania guokunii (96.83 %). Strain ZX-21T contained ubiquinone-8 (Q-8) as the sole isoprenoid quinone and summed feature 3 (C16 : 1ω77c and/or C16 : 1ω66c), summed feature 8 (C18 : 1ω77c and/or C18 : 1ω66c) and C16 : 0 as the major fatty acids. Phosphatidylglycerol (), phosphatidylethanolamine (), diphosphatidylglycerol () and an unidentified glycolipid were the major cellular polar lipids. The DNA G+C content was 49.1 mol%. Based on itsthe morphological, physiological and chemotaxonomic characteristics, strain ZX-21Tis described as a novel species in a novel genus for whichwith the name Marortus luteolus gen. nov., sp. nov. (type strain ZX-21T = MCCC 1K03431T=KCTC 62160T) is proposed.


Asunto(s)
Gammaproteobacteria/clasificación , Filogenia , Agua de Mar/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Gammaproteobacteria/aislamiento & purificación , Glucolípidos/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química
13.
Fish Shellfish Immunol ; 94: 861-870, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31585246

RESUMEN

The main advantage of antimicrobial peptides (AMPs) used as the effectors in the innate immunity system of invertebrates is that the high specificity is not indispensable. And they play important roles in the systemic defenses against microbial invasion. In this study, a new full-length cDNA of the crustins molecule was identified in red swamp crayfish, P. clarkii (named Pc-crustin 4). The ORF of Pc-crustin 4 contained 369 bp which encoded a protein of 122 amino acids, with a 20-amino-acid signal peptide sequence. On the base of the classification method established by Smith et al., Pc-crustin 4 belonged to Type Ⅰ crustin molecule. The Pc-crustin 4 transcripts were expressed in hemocytes at relatively high level, and relatively low level in hepatopancreas, gills, and intestine in normal crayfish. After respectively challenged with S. aureus or E. ictaluri, the expression levels of Pc-crustin 4 showed up-regulation trends at different degrees in the hemocytes, hepatopancreas, gills, and intestine tissues. Besides, the results of liquid antibacterial assay showed that rPc-crustin 4 inhibited obviously the growth of S. aureus and E. ictaluri. The results of bacteria binding assay showed that rPc-crustin 4 could bind strongly to S. aureus and E. ictaluri. Finally, RNAi assay was performed to study the immunity roles of Pc-crustin 4 in crayfish in vivo. Taken together, Pc-crustin 4 is an important immunity effector molecule, which plays crucial roles in defending against bacterial infection in crayfish.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/inmunología , Astacoidea/genética , Astacoidea/inmunología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata/genética , Secuencia de Aminoácidos , Animales , Péptidos Catiónicos Antimicrobianos/química , Proteínas de Artrópodos/química , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/inmunología , Secuencia de Bases , Edwardsiella ictaluri/fisiología , Perfilación de la Expresión Génica , Filogenia , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/inmunología , Alineación de Secuencia , Staphylococcus aureus/fisiología
14.
Fish Shellfish Immunol ; 91: 19-28, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31077848

RESUMEN

Dopa decarboxylase (DDC) is responsible for the synthesis of dopamine, which acts as an important modulator in the nervous systems of vertebrates and invertebrates. Recent studies have indicated that DDC also plays crucial roles in the insect innate immune system. However, the functions of DDC in immunomodulation in crustaceans have not been thoroughly elucidated to date. In this study, a new full-length cDNA of the DDC protein was identified from red swamp crayfish, Procambarus clarkii (named Pc-ddc). The ORF of Pc-ddc encoded 474 amino acids, which possessed a 377-amino-acid domain. Pc-ddc was expressed at a relatively high level in the hemocytes and gills of crayfish. This protein was expressed at a relatively low level in the hepatopancreas and intestine. The expression level of Pc-ddc was clearly upregulated in hemocytes, hepatopancreas, gills, and intestine tissues after challenge with S. aureus or E. ictaluri. The results of the enzyme catalysis assay showed that the enzyme catalysis activity of rPc-DDC was 35 ±â€¯2.8 ng h-1 mg-1 (n = 3). In addition, the results of the mimetic crayfish hemocytes encapsulation assay showed that the encapsulation rate of beads coated with rPc-DDC was clearly increased. The results of the bacterial binding assay showed that rPc-DDC strongly binds to S. aureus and E. ictaluri. Finally, when Pc-ddc was knocked down, the number of surviving crayfish clearly decreased after S. aureus or E. ictaluri was injected. All of these results indicate that Pc-DDC is an important immunomodulating enzyme in the neuroendocrine-immune (NEI) system of crayfish.


Asunto(s)
Dopa-Decarboxilasa/genética , Dopa-Decarboxilasa/inmunología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata/genética , Penaeidae/genética , Penaeidae/inmunología , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/química , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/inmunología , Secuencia de Bases , Dopa-Decarboxilasa/química , Edwardsiella ictaluri/fisiología , Perfilación de la Expresión Génica , Filogenia , Distribución Aleatoria , Alineación de Secuencia , Staphylococcus aureus/fisiología
15.
Fish Shellfish Immunol ; 84: 733-743, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30381264

RESUMEN

Crustins play important roles in defending against bacteria in the innate immunity system of crustaceans. In present study, we identified a crustin gene in Scylla paramamosain, which was named as SpCrus6. The ORF of SpCrus6 possessed a signal peptide sequence (SPS) at the N-terminus and a WAP domain at the C-terminus. And there were 5 Proline residues, 5 Glycine and 4 Cysteine residues between SPS and WAP domain in SpCrus6. These features indicated that SpCrus6 was a new member of crustin family. The SpCrus6 mRNA transcripts were up-regulated obviously after bacteria or virus challenge. These changes showed that SpCrus6 was involved in the antimicrobial and antiviral responses of Scylla paramamosain. Recombinant SpCrus6 (rSpCrus6) showed strong inhibitory abilities against Gram-positive bacteria (Bacillus megaterium, Staphylococcus aureus, and Bacillus subtilis). But the inhibitory abilities against four Gram-negative bacteria (Vibrio parahemolyticus, Vibrio alginolyticus, Vibrio harveyi and Escherichia coli) and two fungi (Pichia pastoris and Candida albicans) were not strong enough. Besides, rSpCrus6 could strongly bind to two Gram-positive bacteria (B. subtilis and B. megaterium) and three Gram-negative bacteria (V. alginolyticus, V. parahemolyticus, and V. harveyi). And the binding levels to S. aureus and two fungi (P. pastoris and C. albicans) were weak. The polysaccharides binding assays' results showed rSpCrus6 had superior binding activities to LPS, LTA, PGN and ß-glucan. Through agglutinating assays, we found rSpCrus6 could agglutinate well three Gram-positive bacteria (S. aureus, B. subtilis and B. megaterium). And the agglutinating activities to Gram-negative bacteria and fungi were not found. In the aspect of antiviral functions, rSpCrus6 could bind specifically to the recombinant envelop protein 26 (rVP26) of white spot syndrome virus (WSSV) but not to recombinant envelop protein 28 (rVP28), whereas GST protein could not bind to rVP26 or rVP28. Besides, rSpCrus6 could suppress WSSV reproduction to some extent. Taken together, SpCrus6 was a multifunctional immunity effector in the innate immunity defending response of S. paramamosain.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/inmunología , Braquiuros/genética , Braquiuros/inmunología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata/genética , Secuencia de Aminoácidos , Animales , Péptidos Catiónicos Antimicrobianos/química , Proteínas de Artrópodos/química , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/inmunología , Secuencia de Bases , Candida albicans/fisiología , Perfilación de la Expresión Génica , Bacterias Gramnegativas/fisiología , Bacterias Grampositivas/fisiología , Filogenia , Pichia/fisiología , Alineación de Secuencia
16.
Mikrochim Acta ; 186(5): 284, 2019 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-30982138

RESUMEN

Photocathodic methods in photoelectrochemical (PEC) analysis are based on the use of functional photocathodes. Heterojunction cathodes consisting of different kinds of semiconductors are being considered as favorite schemes when compared to the single-component ones. A semiconductor heterojunction between CuBi2O4 (CBO) and other semiconductors has not been exploited in PEC assays so far. Herein, CBO nanospheres were initially electrochemically deposited on a fluorine-doped tin oxide (FTO) conductive glass and then coupled to chemically deposited AgI nanoparticles to obtain an electrode of type AgI/CBO/FTO. It was applied as a cathode in the PEC detection of L-cysteine as a model analyte. The sensor can selectively detect L-cysteine, and it is assumed that this is due to the selective interaction between the L-cysteine and both copper and silver via the formation of Cu-S and Ag-S bonds. The photocurrent of the electrode increases linearly with the logarithm of the cysteine concentration in the range from 0.1 and 50 µM, and the detection limit is 0.1 µM. Graphical abstract Schematic presentation of the preparation of an AgI/CuBi2O4 (AgI/CBO) heterojunction on a fluorine-doped tin oxide (FTO) electrode and its application to the cathodic photoelectrochemical detection of L-cysteine.


Asunto(s)
Bismuto/química , Cisteína/análisis , Electroquímica/instrumentación , Flúor/química , Yoduros/química , Procesos Fotoquímicos , Compuestos de Plata/química , Compuestos de Estaño/química , Cisteína/química , Electrodos , Límite de Detección , Semiconductores
17.
J Cell Biochem ; 119(9): 7719-7728, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29878401

RESUMEN

During the progression of osteoarthritis, dysregulation of extracellular matrix (ECM) anabolism, abnormal generation of reactive oxygen species, and proteolytic enzymes have been shown to accelerate the degradation process of cartilage. The purpose of the current study was to investigate the functional role of bromodomain-containing protein 4 (BRD4) in hydrogen peroxide (H2 O2 )-stimulated chondrocyte injury and delineate the underlying molecular mechanisms. We observed that the expression BRD4 was markedly elevated in rat chondrocytes after H2 O2 stimulation. Additionally, inhibition of BRD4 using small interfering RNA or JQ1 (a selective potent chemical inhibitor) led to repression of H2 O2 -induced oxidative stress, as revealed by a decrease in the reactive oxygen species production accompanied by a decreased malondialdehyde content, along with increased activities of antioxidant markers superoxide dismutase, catalase, and glutathione peroxidase on exposure of chondrocytes to H2 O2 . Meanwhile, depletion of BRD4 led to repress the oxidative stress-induced apoptosis of chondrocytes triggered by H2 O2 accompanied by an increase in the expression of anti-apoptotic Bcl-2 and a decrease in the expression of pro-apoptotic Bax and caspase 3 as well as attenuated caspase 3 activity. Moreover, knockdown of BRD4 or treatment with JQ1 markedly attenuated ECM deposition, reflected in a marked upregulation of proteoglycans collagen type II and aggrecan as well as downregulation of ECM-degrading enzymes matrix metalloproteinase 13 and A disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5). More importantly, inhibition of BRD4-activated NF-E2-related factor 2 (Nrf2)-heme oxygenase-1 signaling. Mechanistically, the protective effect of BRD4 inhibition on H2 O2 -stimulated apoptosis and cartilage matrix degeneration was markedly abrogated by Nrf2 depletion. Altogether, we concluded that the protective effect of BRD4 inhibition against oxidative stress-mediated apoptosis and cartilage matrix degeneration occurred through Nrf2-heme oxygenase-1 signaling, implying that BRD4 inhibition may be a more effective therapeutic strategy against osteoarthritis.


Asunto(s)
Condrocitos/citología , Peróxido de Hidrógeno/efectos adversos , Proteínas Nucleares/antagonistas & inhibidores , Estrés Oxidativo/efectos de los fármacos , Factores de Transcripción/antagonistas & inhibidores , Animales , Azepinas/farmacología , Supervivencia Celular , Células Cultivadas , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Matriz Extracelular/metabolismo , Hemo Oxigenasa (Desciclizante)/genética , Hemo Oxigenasa (Desciclizante)/metabolismo , Masculino , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Proteínas Nucleares/genética , ARN Interferente Pequeño/farmacología , Ratas , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Transcripción/genética , Triazoles/farmacología , Regulación hacia Arriba/efectos de los fármacos
18.
Anal Chem ; 90(4): 2749-2755, 2018 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-29359937

RESUMEN

Herein we report the strategy of liposome-mediated Cu2+-induced exciton trapping upon CdS quantum dots (QDs) for amplified photoelectrochemical (PEC) bioanalysis application. Specifically, the Cu nanoclusters (NCs)-encapsulated liposomes were first fabricated and then processed with antibodies bound to their external surfaces. After the sandwich immunocomplexing, the confined liposomal labels were subjected to sequential lysis treatments for the release of Cu NCs and numerous Cu2+ ions, which were then directed to interact with the CdS QDs electrode. The interaction of Cu2+ ions with CdS QDs could generate CuxS and form the trapping sites to block the photocurrent generation. Since the photocurrent inhibition is closely related with the Cu NCs-loaded liposomal labels, a novel and general "signal-off" PEC immunoassay could thus be tailored with high sensitivity. Meanwhile, a complementary "signal-on" fluorescent detection could be accomplished by measuring the fluorescence intensity originated from the Cu NCs. This work features the first use of Cu NCs in PEC bioanalysis and also the first NCs-loaded liposomal PEC bioanalysis. More importantly, by using other specific ions/reagents-semiconductors interactions, this protocol could serve as a common basis for the general development of a new class of liposome-mediated PEC bioanalysis.


Asunto(s)
Técnicas Biosensibles , Cobre/química , Técnicas Electroquímicas , Inmunoensayo , Liposomas/química , Nanopartículas del Metal/química , Compuestos de Cadmio/química , Electrodos , Tamaño de la Partícula , Procesos Fotoquímicos , Puntos Cuánticos/química , Sulfuros/química , Propiedades de Superficie
19.
Anal Chem ; 90(16): 9687-9690, 2018 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-30078328

RESUMEN

This work reports the development of three-dimensional (3D) semiconducting polymer/graphene (SP/G) networks toward sensitive photocathodic enzymatic bioanalysis. Specifically, the porous 3D graphene was first synthesized via the hydrothermal and freeze-dry processes and then mixed with semiconducting polymer to obtain the designed hierarchical structure with unique porosity and large surface area. Afterward, the as-prepared hybrid was immobilized onto the indium tin oxide (ITO) for further characterizations. Exemplified by sarcosine oxidase (SOx) as a model biocatalyst, an innovative 3D SP/G-based photocathodic bioanalysis capable of sensitive and specific sarcosine detection was achieved. The suppression of cathodic photocurrent was observed in the as-developed photocathodic enzymatic biosystem due to the competition of oxygen consumption between the enzyme-biocatalyst process and O2-dependent photocathodic electrode. This work not only presented a unique protocol for 3D SP/G-based photocathodic enzymatic bioanalysis but also provided a new horizon for the design, development, and utilization of numerous 3D platforms in the broad field of general photoelectrochemical (PEC) bioanalysis.


Asunto(s)
Fluorenos/química , Grafito/química , Maleatos/química , Polímeros/química , Poliestirenos/química , Sarcosina-Oxidasa/química , Sarcosina/análisis , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Electrodos , Enzimas Inmovilizadas/química , Fluorenos/efectos de la radiación , Grafito/síntesis química , Luz , Maleatos/efectos de la radiación , Procesos Fotoquímicos , Polímeros/efectos de la radiación , Poliestirenos/efectos de la radiación , Porosidad , Compuestos de Estaño/química
20.
Phys Rev Lett ; 120(17): 170501, 2018 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-29756821

RESUMEN

Quantifying coherence has received increasing attention, and considerable work has been directed towards finding coherence measures. While various coherence measures have been proposed in theory, an important issue following is how to estimate these coherence measures in experiments. This is a challenging task, since the state of a system is often unknown in practical applications and the accessible measurements in a real experiment are typically limited. In this Letter, we put forward an approach to estimate coherence measures of an unknown state from any limited experimental data available. Our approach is not only applicable to coherence measures but can be extended to other resource measures.

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