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1.
Biosens Bioelectron ; 197: 113758, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34798499

RESUMO

In this work, a "signal-off" electrochemical biosensor was established for sensitive detection of adenosine triphosphate (ATP) based on Fe3O4@covalent organic framework-immobilized gold nanoparticles (Fe3O4@COF-Au NPs) porous composite material as a nanocarrier. The proposed Fe3O4@COF-Au NPs could effectively confine Au NPs in the uniform channels of the Fe3O4@COF, which successfully avoided Au NPs aggregation to a certain extent and provided a comparatively independent and stable micro-environment via its hydrophobic porous nanochannels, thereby owning excellent electro-catalytic performance for the reduction of 4-nitrophenol. Moreover, the Fe3O4@COF-Au NPs nanomaterials were served as functional platform for immobilizing DNA substrate (S0), which was used to bind with the conversion product (S1) of the target ATP for subsequent branched hybridization chain reaction (b-HCR) to form dendritic DNA strands to hinder electron transfer between Fe3O4@COF-Au NPs and 4-nitrophenol, finally achieving sensitive detection of ATP with a wide linear range of 5 pM-50 µM and a low detection limit of 1.6 pM. Such strategy provides a multifunctional immobilized platform for the sensitive detection of ATP and a versatile strategy for monitoring other biomolecules.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Trifosfato de Adenosina , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Porosidade
2.
Biochim Biophys Acta Biomembr ; 1864(1): 183782, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34555418

RESUMO

Transient receptor potential vanilloid 1 (TRPV1) is a voltage-dependent non-selective cation channel activated by capsaicin, the main pungent ingredient of chili peppers, and noxious heat. Although TRPV1 channels produce outwardly rectifying currents even in the absence of capsaicin, little is known about the regulation mechanism of the TRPV1 currents. In the present study, we found that intracellular ATP regulates the basal activities of TRPV1 channels in a concentration-dependent manner. The ATP-dependent regulation of TRPV1 channels was mediated by phosphoinositides. Moreover, an increase in intracellular ATP concentration negatively shifted voltage-dependent activation of TRPV1 channels. These results suggest that the ATP-dependent production of phosphoinositides regulates the voltage-dependent gating of the basal TRPV1 channel activities in the absence of capsaicin.


Assuntos
Capsaicina/metabolismo , Fosfatidilinositóis/química , Canais de Cátion TRPV/química , Trifosfato de Adenosina/metabolismo , Capsicum/química , Fosfatidilinositóis/genética , Canais de Cátion TRPV/genética
3.
Biochim Biophys Acta Proteins Proteom ; 1870(1): 140720, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597835

RESUMO

Kinases play central roles in many cellular processes, transferring the terminal phosphate groups of nucleoside triphosphates (NTPs) onto substrates. In the absence of substrates, kinases can also hydrolyse NTPs producing NDPs and inorganic phosphate. Hydrolysis is usually much less efficient than the native phosphoryl transfer reaction. This may be related to the fact that NTP hydrolysis is metabolically unfavorable as it unproductively consumes the cell's energy stores. It has been suggested that substrate interactions could drive changes in NTP binding pocket, activating catalysis only when substrates are present. Structural data show substrate-induced conformational rearrangements, however there is a lack of corresponding functional information. To better understand this phenomenon, we developed a suite of isothermal titration calorimetry (ITC) kinetics methods to characterize ATP hydrolysis by the antibiotic resistance enzyme aminoglycoside-3'-phosphotransferase-IIIa (APH(3')-IIIa). We measured Km, kcat, and product inhibition constants and single-turnover kinetics in the presence and absence of non-substrate aminoglycosides (nsAmgs) that are structurally similar to the native substrates. We found that the presence of an nsAmg increased the chemical step of cleaving the ATP γ-phosphate by at least 10- to 20-fold under single-turnover conditions, supporting the existence of interactions that link substrate binding to substantially enhanced catalytic rates. Our detailed kinetic data on the association and dissociation rates of nsAmgs and ADP shed light on the biophysical processes underlying the enzyme's Theorell-Chance reaction mechanism. Furthermore, they provide clues on how to design small-molecule effectors that could trigger efficient ATP hydrolysis and generate selective pressure against bacteria harboring the APH(3')-IIIa.


Assuntos
Trifosfato de Adenosina/metabolismo , Domínio Catalítico , Canamicina Quinase/metabolismo , Regulação Alostérica , Aminoglicosídeos/metabolismo , Hidrólise , Canamicina Quinase/química , Cinética , Ligação Proteica
4.
Meat Sci ; 183: 108641, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34365254

RESUMO

The aim of this study was to investigate the course of glycogenolysis, ATP breakdown and fragmentation of myofibrillar proteins in the semitendinosus muscle of a progeny of Limousin×Holstein-Friesian (LMx) and Charolaise×Holstein-Friesian (CHx) (bulls and steers) and to describe the changes in the above parameters over time and its relationship with beef texture. The hypothesis that beef from bulls and steers of different crossbreeds required the same ageing time to achieve satisfactory tenderness was also tested. Cattle crossbreeding did not affect the amount of muscle glycogen, and castration did not differentiate it until 3 h post-mortem. The interaction between crossbreeding and castration was found, and the highest shear force values were observed in CHx bulls, whereas the lowest was in CHx steers. Beef obtained from CHx was found to be more predestined to short ageing, and LMx required longer ageing to achieve good tenderness. The R-values more strongly influenced subsequent beef texture than pH values.


Assuntos
Músculo Esquelético/química , Carne Vermelha/análise , Resistência ao Cisalhamento , Trifosfato de Adenosina/metabolismo , Animais , Bovinos , Manipulação de Alimentos/métodos , Glicogênio/análise , Hibridização Genética , Concentração de Íons de Hidrogênio , Masculino , Proteínas Musculares/metabolismo , Miofibrilas/química , Orquiectomia/veterinária , Fatores de Tempo
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 265: 120341, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492515

RESUMO

Adenosine triphosphate (ATP) is an energy molecule of significant importance, and, the monitoring of ATP in living cells is considerable for the clinical diagnosis of many related diseases, including cancer. Upconversion nanoparticles (UCNPs) have recently been attracting widespread interest in biomedical applications due to their chemical and thermal stability, high sensitivity, good biocompatibility, and excellent tissue penetration. Herein, a Cy3-aptamer-cDNA- UCNPs nanosensor was synthesized, based on the luminescence resonance energy transfer (LRET) between UCNPs and Cy3 for monitoring ATP in living cells. It showed a selective sensing ability for ATP levels by changes of fluorescence intensity of UNCPs at 536 nm. The investigated biosensor showed a precise, efficient detection with sufficient selectivity which was achieved through the optimization of conditions. In the range of 1-1000 µM, the ATP-induced changes of the fluorescence intensity were linearly proportional to the ATP concentrations. Furthermore, the cytotoxicity assay revealed that the UCNPs sensor exhibited favorable biocompatibility, implicating the use of UCNPs in vivo imaging. This study highlights the potential of using a combination of UCNPs and ATP-binding aptamer to design an ATP-activatable probe for fluorescence-mediated imaging in living cells. These results implied that the nanosensor can be applicable for the monitoring of intracellular ATP by fluorescence imaging and the quantitative analysis of biological liquids.


Assuntos
Técnicas Biossensoriais , Nanopartículas , Trifosfato de Adenosina , Transferência Ressonante de Energia de Fluorescência , Luminescência
6.
Endocrinology ; 163(1)2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34718519

RESUMO

Pancreatic ß-cells can secrete insulin via 2 pathways characterized as KATP channel -dependent and -independent. The KATP channel-independent pathway is characterized by a rise in several potential metabolic signaling molecules, including the NADPH/NADP+ ratio and α-ketoglutarate (αKG). Prolyl hydroxylases (PHDs), which belong to the αKG-dependent dioxygenase superfamily, are known to regulate the stability of hypoxia-inducible factor α. In the current study, we assess the role of PHDs in vivo using the pharmacological inhibitor dimethyloxalylglycine (DMOG) and generated ß-cell-specific knockout (KO) mice for all 3 isoforms of PHD (ß-PHD1 KO, ß-PHD2 KO, and ß-PHD3 KO mice). DMOG inhibited in vivo insulin secretion in response to glucose challenge and inhibited the first phase of insulin secretion but enhanced the second phase of insulin secretion in isolated islets. None of the ß-PHD KO mice showed any significant in vivo defects associated with glucose tolerance and insulin resistance except for ß-PHD2 KO mice which had significantly increased plasma insulin during a glucose challenge. Islets from both ß-PHD1 KO and ß-PHD3 KO had elevated ß-cell apoptosis and reduced ß-cell mass. Isolated islets from ß-PHD1 KO and ß-PHD3 KO had impaired glucose-stimulated insulin secretion and glucose-stimulated increases in the ATP/ADP and NADPH/NADP+ ratio. All 3 PHD isoforms are expressed in ß-cells, with PHD3 showing the most distinct expression pattern. The lack of each PHD protein did not significantly impair in vivo glucose homeostasis. However, ß-PHD1 KO and ß-PHD3 KO mice had defective ß-cell mass and islet insulin secretion, suggesting that these mice may be predisposed to developing diabetes.


Assuntos
Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Prolil Hidroxilases/metabolismo , Isoformas de Proteínas/química , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Apoptose , Regulação da Expressão Gênica , Glucose/metabolismo , Teste de Tolerância a Glucose , Homeostase , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ácidos Cetoglutáricos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADP/metabolismo , Fosforilação Oxidativa , Consumo de Oxigênio , Fenótipo , Domínios Proteicos
7.
Methods Mol Biol ; 2387: 219-230, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34643916

RESUMO

The oxidative phosphorylation (OxPhos) pathway has emerged as an attractive pathway for the development of anti-mycobacterial drugs. The OxPhos pathway is essential for ATP resynthesis and maintenance of the electrochemical transmembrane gradient. The bioenergetic parameters of the pathway such as oxygen consumption rate and ATP levels are quantifiable using current technology. Measuring these parameters are useful tools to gauge rapidly the impact of drug candidates on their capacity to inhibit the OxPhos pathway in Mycobacterium ulcerans.


Assuntos
Mycobacterium ulcerans , Trifosfato de Adenosina , Úlcera de Buruli , Metabolismo Energético , Humanos
8.
Nanoscale ; 14(1): 26-34, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34897352

RESUMO

Most current biosensors were designed for the detection of individual analytes, or a group of chemically similar analytes. We reason that sensors designed to track both reactants and products might be useful for following chemical reactions. Adenosine triphosphate (ATP) is a key biomolecule that participates in various biochemical reactions, and its hydrolysis plays a fundamental role in life. ATP can be converted to adenosine diphosphate (ADP) and inorganic phosphate (Pi) via the dephosphorylation process. ATP can also be hydrolyzed to adenosine monophosphate (AMP) and pyrophosphate (PPi) through depyrophosphorylation, depending on where the bond is cleaved. The detection of ATP-related hydrolysates would enable a better understanding of the different reaction pathways with a high level of robustness and confidence. Herein, we prepared a fluorescent sensor array based on a series of bimetallic zeolite imidazole frameworks M/ZIF-8 (M = Ni, Mn, Cu) and ZIF-67 to discriminate ATP hydrolysis and detect ATP hydrolysis related analytes. A fluorescently-labeled DNA oligonucleotide was used for signaling. Interestingly, Cu/ZIF-8 exhibited an ultrahigh selectivity for recognizing pyrophosphate with a detection limit of 2.5 µM. Moreover, the practicality of this sensor array was demonstrated in fetal bovine serum, clearly discriminating ATP hydrolysis products.


Assuntos
Trifosfato de Adenosina , Zeolitas , DNA , Hidrólise , Fosfatos
9.
Viruses ; 13(12)2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34960780

RESUMO

Broad-spectrum antiviral therapies hold promise as a first-line defense against emerging viruses by blunting illness severity and spread until vaccines and virus-specific antivirals are developed. The nucleobase favipiravir, often discussed as a broad-spectrum inhibitor, was not effective in recent clinical trials involving patients infected with Ebola virus or SARS-CoV-2. A drawback of favipiravir use is its rapid clearance before conversion to its active nucleoside-5'-triphosphate form. In this work, we report a synergistic reduction of flavivirus (dengue, Zika), orthomyxovirus (influenza A), and coronavirus (HCoV-OC43 and SARS-CoV-2) replication when the nucleobases favipiravir or T-1105 were combined with the antimetabolite 6-methylmercaptopurine riboside (6MMPr). The 6MMPr/T-1105 combination increased the C-U and G-A mutation frequency compared to treatment with T-1105 or 6MMPr alone. A further analysis revealed that the 6MMPr/T-1105 co-treatment reduced cellular purine nucleotide triphosphate synthesis and increased conversion of the antiviral nucleobase to its nucleoside-5'-monophosphate, -diphosphate, and -triphosphate forms. The 6MMPr co-treatment specifically increased production of the active antiviral form of the nucleobases (but not corresponding nucleosides) while also reducing levels of competing cellular NTPs to produce the synergistic effect. This in-depth work establishes a foundation for development of small molecules as possible co-treatments with nucleobases like favipiravir in response to emerging RNA virus infections.


Assuntos
Antimetabólitos/farmacologia , Antivirais/farmacologia , Vírus de RNA/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Amidas/farmacologia , Animais , Linhagem Celular , Sinergismo Farmacológico , Guanosina Trifosfato/metabolismo , Humanos , Metiltioinosina/farmacologia , Mutação/efeitos dos fármacos , Fosforribosil Pirofosfato/metabolismo , Pirazinas/farmacologia , Vírus de RNA/classificação , Vírus de RNA/genética , RNA Viral/efeitos dos fármacos , RNA Viral/genética , Replicação Viral/efeitos dos fármacos
10.
Cells ; 10(12)2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34944107

RESUMO

Mitochondria move along the microtubule network and produce bioenergy in the cell. However, there is no report of a relationship between bioenergetic activity of mitochondria and microtubule stability in mammalian cells. This study aimed to investigate this relationship. We treated HEK293 cells with microtubule stabilizers (Taxol and Epothilone D) or a microtubule disturber (vinorelbine), and performed live-cell imaging to determine whether mitochondrial morphology and bioenergetic activity depend on the microtubule status. Treatment with microtubule stabilizers enhanced the staining intensity of microtubules, significantly increased ATP production and the spare respiratory capacity, dramatically increased mitochondrial fusion, and promoted dynamic movement of mitochondria. By contrast, bioenergetic activity of mitochondria was significantly decreased in cells treated with the microtubule disturber. Our data suggest that microtubule stability promotes mitochondrial functional activity. In conclusion, a microtubule stabilizer can possibly recover mitochondrial functional activity in cells with unstable microtubules.


Assuntos
Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Trifosfato de Adenosina/biossíntese , Proliferação de Células , Respiração Celular , Forma Celular , Sobrevivência Celular , Regulação da Expressão Gênica , Células HEK293 , Humanos , Potencial da Membrana Mitocondrial , Consumo de Oxigênio , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
11.
Cell Mol Life Sci ; 79(1): 7, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34936028

RESUMO

Amyotrophic lateral sclerosis is a fatal neurodegenerative disorder that leads to progressive degeneration of motor neurons and severe muscle atrophy without effective treatment. Most research on the disease has been focused on studying motor neurons and supporting cells of the central nervous system. Strikingly, the recent observations have suggested that morpho-functional alterations in skeletal muscle precede motor neuron degeneration, bolstering the interest in studying muscle tissue as a potential target for the delivery of therapies. We previously showed that the systemic administration of the P2XR7 agonist, 2'(3')-O-(4-benzoylbenzoyl) adenosine 5-triphosphate (BzATP), enhanced the metabolism and promoted the myogenesis of new fibres in the skeletal muscles of SOD1G93A mice. Here we further corroborated this evidence showing that intramuscular administration of BzATP improved the motor performance of ALS mice by enhancing satellite cells and the muscle pro-regenerative activity of infiltrating macrophages. The preservation of the skeletal muscle retrogradely propagated along with the motor unit, suggesting that backward signalling from the muscle could impinge on motor neuron death. In addition to providing the basis for a suitable adjunct multisystem therapeutic approach in ALS, these data point out that the muscle should be at the centre of ALS research as a target tissue to address novel therapies in combination with those oriented to the CNS.


Assuntos
Esclerose Amiotrófica Lateral/metabolismo , Esclerose Amiotrófica Lateral/fisiopatologia , Atividade Motora/fisiologia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Receptores Purinérgicos P2X7/metabolismo , Trifosfato de Adenosina/administração & dosagem , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Animais , Axônios/patologia , Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Denervação , Modelos Animais de Doenças , Progressão da Doença , Feminino , Membro Posterior/patologia , Humanos , Inflamação/patologia , Injeções Intramusculares , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos Transgênicos , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/patologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/inervação , Atrofia Muscular/patologia , Fenótipo , Células Satélites de Músculo Esquelético/efeitos dos fármacos , Células Satélites de Músculo Esquelético/patologia , Células de Schwann/patologia , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/patologia
12.
Anal Chim Acta ; 1188: 339180, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34794559

RESUMO

CRISPR-Cas12a system exhibits tremendous potential in accurate recognition and quantitation of nucleic acids and non-nucleic-acid targets thanks to the discovery of its cleavage capability toward single-stranded DNA (ssDNA). In this study, we developed an efficient electrochemiluminescence (ECL) sensing platform based on CRISPR-Cas12a for the analysis of adenosine triphosphate (ATP). In the presence of the target, the successful release of the DNA activator is specially recognized by Cas12a-crRNA duplex and activates the cleavage of ferrocene (Fc) labeled-ssDNA (Fc-ssDNA) modified on the cathode of bipolar electrode (BPE), resulting in a decrease of ECL intensity of [Ru(bpy)3]2+/TPrA in the anodic cell of BPE. By means of the unique combination of Cas12a with ECL technique based on BPE, it can convert the recognition of target ATP into a detectable ECL signal. The detection limit of ATP was determined to be 0.48 nM under the optimal conditions. This work will expand the application of CRISPR-Cas detection system and propose a potential method for the analysis of non-nucleic-acid targets.


Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas , Trifosfato de Adenosina , DNA , Eletrodos , Medições Luminescentes
13.
Anal Chim Acta ; 1188: 339167, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34794583

RESUMO

ATP-sensitive potassium (KATP) channels couple intracellular metabolism to the electrical activity by regulating K+ flux across the plasma membrane, thus playing an important role in both normal and pathophysiology. To understand the mechanism of ATP regulating biological ion channels, developing an ATP-responsive artificial nanochannel is an appealing but challenging topic because KATP channel is a heteromultimer of two subunits (potassium channel subunit (Kir6.x) and sulfonylurea receptor (SUR)) and exhibit dynamic functions with adjustability and reversibility. Inspired by the structure of KATP channels, we designed a smart copolymer modified nanochannel that may address the challenge. In the tricomponent poly(N-isopropylacrylamide) (PNIPAAm, PNI)-based copolymer system, phenylthiourea was used to bind the phosphate units of nucleotides and phenylboronic acid was introduced to combine the pentose ring of the nucleoside unit. Besides, a -COOH group with electron-withdrawing property was added into the phenylthiourea units, which may promote the hydrogen-bond-donating ability of thiourea. Specially, the smart copolymer not only provided static binding sites for recognition but also translated the recognition of ATP into their dynamic conformational transitions by changing the hydrogen-bonding environments surrounding PNIPAAm chains, thus achieving the gating function of nanochannel, which resembled the integration and coordination of Kir6.x and SUR units in active KATP. The ATP-regulated ion channel exhibited excellent stability and reversibility. This study is the first example showing how to learn from nature to assemble the ATP-responsive artificial nanochannel and demonstrate the possible mechanism of ATP gating.


Assuntos
Trifosfato de Adenosina , Biomimética , Sítios de Ligação , Nucleotídeos , Receptores de Sulfonilureias
14.
Front Cell Infect Microbiol ; 11: 724912, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34796124

RESUMO

We previously demonstrated the immunostimulatory efficacy of Pseudomonas aeruginosa flagellar hook protein FlgE on epithelial cells, presumably via ectopic ATP synthases or subunits ATP5B on cell membranes. Here, by using recombinant wild-type FlgE, mutant FlgE (FlgEM; bearing mutations on two postulated critical epitopes B and F), and a FlgE analog in pull-down assay, Western blotting, flow cytometry, and ELISA, actual bindings of FlgE proteins or epitope B/F peptides with ATP5B were all confirmed. Upon treatment with FlgE proteins, human umbilical vein endothelial cells (HUVECs) and SV40-immortalized murine vascular endothelial cells manifested decreased proliferation, migration, tube formation, and surface ATP production and increased apoptosis. FlgE proteins increased the permeability of HUVEC monolayers to soluble large molecules like dextran as well as to neutrophils. Immunofluorescence showed that FlgE induced clustering and conjugation of F-actin in HUVECs. In Balb/c-nude mice bearing transplanted solid tumors, FlgE proteins induced a microvascular hyperpermeability in pinna, lungs, tumor mass, and abdominal cavity. All effects observed in FlgE proteins were partially or completely impaired in FlgEM proteins or blocked by pretreatment with anti-ATP5B antibodies. Upon coculture of bacteria with HUVECs, FlgE was detectable in the membrane and cytosol of HUVECs. It was concluded that FlgE posed a pathogenic ligand of ectopic ATP5B that, upon FlgE-ATP5B coupling on endothelial cells, modulated properties and increased permeability of endothelial layers both in vitro and in vivo. The FlgE-ectopic ATP5B duo might contribute to the pathogenesis of disorders associated with bacterial infection or ectopic ATP5B-positive cells.


Assuntos
Proteínas de Bactérias , Flagelos , Trifosfato de Adenosina , Animais , Proteínas de Bactérias/genética , Células Endoteliais , Camundongos , Camundongos Nus
15.
Anal Chem ; 93(46): 15331-15339, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34756034

RESUMO

DNA logic nanodevices have prospects in molecular recognitions but still face challenges in achieving DNA computation-controlled regulation in specific compartments of living cells. By incorporating the i-motif sequence and ATP aptamers into a Y-shaped DNA (Y-DNA) structure, and applying gold nanoparticles (AuNPs) as the transporting carrier, herein we present a new type of DNA logic nanodevices to monitor the ATP levels in lysosomes of living cells. Triple energy transfers including dual fluorescent resonance energy transfers (FRETs) and a nanometal surface energy transfer (NSET) occurred in the DNA logic nanodevices. It was identified that the proposed nanodevices perform an AND logic operation to output FRET signals only when an endogenous proton and ATP simultaneously exist in the cellular microenvironment. Owing to the use of the i-motif sequence, the nanodevices have lysosome-recognizing capacity without causing alkalization of the acidic organelle, making DNA computation-controlled regulation at the level of cellular organelles achievable. These DNA logic nanodevices show high application prospects in lysosome-related cellular function and disease treatment.


Assuntos
Ouro , Nanopartículas Metálicas , Trifosfato de Adenosina , DNA , Lógica , Lisossomos
16.
Radiol Technol ; 93(2): 141-149, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34728576

RESUMO

PURPOSE: To explore the level of bioburden and the effectiveness of the manufacturers' recommended cleaning methods on lead apparel in a radiology department. METHODS: A 2-phase experiment at a level II trauma center during a 2-year period assessed the level of bioburden on radiology lead apparel. Adenosine triphosphate swabs and a luminometer were used to measure cleanliness of high-touch areas. Cleanliness was measured before and after 3 cleaning methods were used: cleaning with a mild detergent and water; cleaning with a mild detergent, water, and then a disinfectant; and scrubbing with cleaning wipes. RESULTS: Average bioburden levels exceeded facility thresholds for all areas and types of lead apparel examined. All tested cleaning methods significantly reduced bioburden. DISCUSSION: Monthly cleaning of lead apparel provides improved cleanliness when compared with quarterly cleaning. Daily cleaning of lead apparel that will be used in a sterile environment is recommended. Future research might include examining other patient care and ancillary equipment found in the imaging department for potential bioburden and surveying technologists to examine practices for routine removal of bioburden from equipment. CONCLUSION: Health care professionals must be aware of the potential bioburden on clinical equipment and maintain an effective cleaning practice and schedule to reduce the possibility of spreading infection.


Assuntos
Infecção Hospitalar , Desinfecção , Trifosfato de Adenosina , Humanos , Controle de Infecções
18.
Biomater Sci ; 9(22): 7456-7470, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34609385

RESUMO

Severe hypoxia in solid tumors limits the efficacy of oxygen (O2)-dependent photodynamic therapy (PDT). The overexpressed heat shock proteins (HSPs) in tumor cells hamper the effect of photothermal therapy (PTT). Herein, a tumor oxygenation-enhanced and ATP-reduced gelatin nanoreactor (MCGPD ∼ RGD NPs) for PDT/PTT-augmented combination cancer therapy is reported. In this nanosystem, the Arg-Gly-Asp (RGD) peptides of MCGPD ∼ RGD NPs can ensure accurate recognition and sufficient accumulation in the tumor site. After accumulation, doxorubicin (DOX) can be released from MCGPD ∼ RGD NPs in a mild acidic tumor microenvironment (TME) for highly efficient chemotherapy. Upon 808 nm laser irradiation, the overexpressed matrix metalloproteinase-2 (MMP-2) in the TME and the heat produced from the PDA coating trigger Gel NP degradation to expose chlorin e6 (Ce6) and Met from the cavity of MCGPD ∼ RGD NPs. The exposed Met elevates the O2 content and reduces ATP production in tumor sites to spur the successful O2-dependent PDT and HSP-mediated PTT. The heat generated by the PDA coating directly kills the tumor cells to ensure PTT and amplifies the chemotherapeutic effect. In vitro and in vivo assays indicate that MCGPD ∼ RGD NPs have excellent ability to promote cell apoptosis and to inhibit tumor growth. Overall, this smart responsive hydrogel nanosystem with hypoxia-relieving capacity and ATP-decreasing performance provides a promising strategy against cancer.


Assuntos
Metformina , Nanopartículas , Neoplasias , Fotoquimioterapia , Trifosfato de Adenosina , Linhagem Celular Tumoral , Humanos , Hipóxia , Metaloproteinase 2 da Matriz , Nanotecnologia , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Microambiente Tumoral
19.
Rom J Morphol Embryol ; 62(1): 179-190, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34609420

RESUMO

Testicular torsion is a urological problem that causes subfertility and testicular damage in males. Testis torsion and detorsion lead to ischemia-reperfusion (IR) injury in the testis. Testicular IR injury causes the increase of reactive oxygen species (ROS), oxidative stress (OS) and germ cell-specific apoptosis. In this study, we aimed to investigate whether Carvacrol has a protective effect on testicular IR injury and its effects on Kir6.2 channels, which is a member of adenosine triphosphate (ATP)-dependent potassium channels. In the study, 2-4 months old 36 albino Wistar rats were used. For experimental testicular IR model, the left testis was rotated counterclockwise at 720° for two hours, and after two hours following torsion, detorsion was performed. Carvacrol was dissolved in 5% Dimethyl Sulfoxide (DMSO) at a dose of 73 mg∕kg and half an hour before detorsion, 0.2 mL was administered intraperitoneally. In testicular tissues, caspase 3 and Kir6.2 immunoexpressions were examined. Serum malondialdehyde (MDA) and testosterone levels were measured. Apoptotic cells and serum MDA levels were significantly decreased and Kir6.2 activation was significantly increased in Carvacrol-administrated IR group. As a result of our study, Carvacrol may activates Kir6.2 channels and inhibits apoptosis and may have a protective effect on testicular IR injury.


Assuntos
Traumatismo por Reperfusão , Torção do Cordão Espermático , Trifosfato de Adenosina , Animais , Apoptose , Cimenos , Humanos , Masculino , Malondialdeído , Potássio , Canais de Potássio , Ratos , Traumatismo por Reperfusão/tratamento farmacológico , Torção do Cordão Espermático/tratamento farmacológico , Testículo
20.
Nat Commun ; 12(1): 5911, 2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34625545

RESUMO

Immune cells at sites of inflammation are continuously activated by local antigens and cytokines, and regulatory mechanisms must be enacted to control inflammation. The stepwise hydrolysis of extracellular ATP by ectonucleotidases CD39 and CD73 generates adenosine, a potent immune suppressor. Here we report that human effector CD8 T cells contribute to adenosine production by releasing CD73-containing extracellular vesicles upon activation. These extracellular vesicles have AMPase activity, and the resulting adenosine mediates immune suppression independently of regulatory T cells. In addition, we show that extracellular vesicles isolated from the synovial fluid of patients with juvenile idiopathic arthritis contribute to T cell suppression in a CD73-dependent manner. Our results suggest that the generation of adenosine upon T cell activation is an intrinsic mechanism of human effector T cells that complements regulatory T cell-mediated suppression in the inflamed tissue. Finally, our data underscore the role of immune cell-derived extracellular vesicles in the control of immune responses.


Assuntos
5'-Nucleotidase/metabolismo , Adenosina/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Vesículas Extracelulares/metabolismo , Proteínas Ligadas por GPI/metabolismo , 5'-Nucleotidase/genética , Trifosfato de Adenosina , Animais , Autoimunidade , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Vesículas Extracelulares/imunologia , Humanos , Inflamação , Ativação Linfocitária , Camundongos , Linfócitos T , Linfócitos T Reguladores/imunologia
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