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1.
Sci Adv ; 10(25): eadj9251, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38905347

RESUMEN

Quantum entanglement is crucial for quantum information processing, prominently used in quantum communication, computation, and metrology. Recent studies have shifted toward high-dimensional entangled states, offering greater information capacity and enabling more complex applications. Here, we experimentally prepared a three-photon asymmetric maximally entangled state, comprising two two-dimensional photons and one four-dimensional photon. Using this state, we conducted a proof-of-principle experiment, successfully transferring a four-dimensional quantum state from two photons to another photon with fidelities ranging from 0.78 to 0.86. These results exceed theoretical limits, demonstrating genuine four-dimensional quantum state transfer. The asymmetric entangled state demonstrated here holds promise for future quantum networks as a quantum interface facilitating information transfer across quantum systems with different dimensions.

2.
J Colloid Interface Sci ; 658: 728-738, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38141394

RESUMEN

Seeking cathode materials with high areal capacity and excellent cycling tolerance is a key step to develop aqueous rechargeable zinc-based alkaline batteries with high energy density, power density and excellent stability. Here, the bilayered cathode composite (MCN-LDH@CP) of molybdate intercalated cobalt-nickel layered hydroxide nanosheets (MCN-LDH) grown on cobalt phosphate octahydrate microsheet (CP) was prepared by a two-step hydrothermal process. Molybdate intercalation significantly reduces the thickness of cobalt-nickel layered hydroxide, greatly increases its specific surface area, regulates its pore distribution, increases the crystal plane spacing, promotes the diffusion rate of hydroxide in it, and increases its specific capacity. Meanwhile, the bilayered MCN-LDH@CP electrode significantly improved the areal energy density (2.89 mWh/cm2) and peak power density (111.22 mW/cm2) and cycle stability (97.8 % after 7000 cycles) of the CoNi//Zn battery. The excellent stability is mainly due to the fact that the MCN-LDH overlay inhibits the loss of P element of CP and improves the structural stability of the sample. The quasi-solid-state MCN-LDH@CP//Zn battery can still charge a mobile phone even when hammered and pierced, showing excellent safety and reliability. This work opens a new avenue to develop CoNi//Zn batteries with high energy density, power density and excellent tolerance.

3.
Cells ; 11(22)2022 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-36429080

RESUMEN

Ischemia-reperfusion (I/R) is a common pathological phenomenon that occurs in numerous organs and diseases. It generally results from secondary damage caused by the recovery of blood flow and reoxygenation, followed by ischemia of organ tissues, which is often accompanied by severe cellular damage and death. Currently, effective treatments for I/R injury (IRI) are limited. Ferroptosis, a new type of regulated cell death (RCD), is characterized by iron overload and iron-dependent lipid peroxidation. Mounting evidence has indicated a close relationship between ferroptosis and IRI. Ferroptosis plays a significantly detrimental role in the progression of IRI, and targeting ferroptosis may be a promising approach for treatment of IRI. Considering the substantial progress made in the study of ferroptosis in IRI, in this review, we summarize the pathological mechanisms and therapeutic targets of ferroptosis in IRI.


Asunto(s)
Ferroptosis , Sobrecarga de Hierro , Daño por Reperfusión , Humanos , Daño por Reperfusión/metabolismo , Peroxidación de Lípido , Sobrecarga de Hierro/complicaciones , Hierro/metabolismo
4.
Bosn J Basic Med Sci ; 22(6): 872-881, 2022 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-35699749

RESUMEN

Interleukin-1 receptor-associated kinase 1/4 (IRAK1/4) is the main kinase of the Toll-like receptor (TLR)-mediated pathway, considered a new target for treating inflammatory diseases. Studies showed a significant correlation between TLRs and inflammatory responses in ulcerative colitis (UC). Therefore, in this study, after inducing experimental colitis in mice with 3% dextran sulfate sodium (DSS), different concentrations of IRAK1/4 inhibitors were administered intraperitoneally. Then, the disease activity index was assessed, including the degree of pathological damage, by HE staining. Subsequently, while western blotting detected the TLR4/NF-κB pathway and intestinal barrier protein expression (Zonula-1, Occludin, Claudin-1, JAM-A), real-time polymerase chain reaction (RT-PCR) detected the mRNA expression levels of IRAK1/4 and mucin1/2. Furthermore, the expression levels of Zonula-1 and occludin were detected by immunofluorescence, including the plasma FITC-dextran 4000 concentration, to evaluate intestinal barrier permeability. However, ELISA measured the expression of inflammatory factors to reflect intestinal inflammation in mice. Investigations showed that the IRAK 1/4 inhibitor significantly reduced clinical symptoms and pathological DSS-induced colitis damage in mice and then inhibited the cytoplasmic and nuclear translocation of NF-κB p65, including the phosphorylation of IκBα and reduction in downstream inflammatory factor production. Therefore, we established that the IRAK1/4 inhibitor effectively improves colitis induced by DSS, partly by inhibiting the TLR4/NF-κB pathway, reducing inflammation, and maintaining the integrity of the colonic barrier.


Asunto(s)
Colitis Ulcerosa , Colitis , Animales , Ratones , Claudina-1/metabolismo , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Inflamación , Quinasas Asociadas a Receptores de Interleucina-1/antagonistas & inhibidores , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Inhibidor NF-kappaB alfa/metabolismo , Ocludina/metabolismo , ARN Mensajero , Transducción de Señal , Receptor Toll-Like 4/metabolismo
5.
Oxid Med Cell Longev ; 2022: 3846217, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35656025

RESUMEN

Ferroptosis, a novel form of regulated cell death characterized by disrupted iron metabolism and the accumulation of lipid peroxides, has exhibited enormous potential in the therapy of cancer particularly clear cell renal cell carcinoma (ccRCC). Luteolin (Lut), a natural flavonoid widely existing in various fruits and vegetables, has been proven to exert potent anticancer activity in vitro and in vivo. However, previous studies on the anticancer mechanism of Lut have been shown in apoptosis but not ferroptosis. In the present study, we identified that Lut substantially inhibited the survival of ccRCC in vitro and in vivo, and this phenomenon was accompanied by excessively increased intracellular Fe2+ and abnormal depletion of GSH. In addition, Lut induced the imbalance of mitochondrial membrane potential, classical morphological alterations of mitochondrial ferroptosis, generation of ROS, and occurrence of lipid peroxidation in an iron-dependent manner in ccRCC cells. However, these alterations induced by Lut could be reversed to some extent by the iron ion chelator deferiprone or the ferroptosis inhibitor ferrostatin-1, indicating that ccRCC cells treated with Lut underwent ferroptosis. Mechanistically, molecular docking further established that Lut probably promoted the heme degradation and accumulation of labile iron pool (LIP) by excessively upregulating the HO-1 expression, which led to the Fenton reaction, GSH depletion, and lipid peroxidation in ccRCC, whereas blocking this signaling pathway evidently rescued the Lut-induced cell death of ccRCC by inhibiting ferroptosis. Altogether, the current study shows that the natural compound monomer Lut exerted anticancer efficacy by excessively upregulating HO-1 expression and activating LIP to trigger ferroptosis in ccRCC and could be a promising and potent drug candidate for ccRCC treatment.


Asunto(s)
Carcinoma de Células Renales , Ferroptosis , Neoplasias Renales , Carcinoma de Células Renales/tratamiento farmacológico , Humanos , Hierro/metabolismo , Neoplasias Renales/tratamiento farmacológico , Peroxidación de Lípido , Luteolina/farmacología , Simulación del Acoplamiento Molecular , Especies Reactivas de Oxígeno/metabolismo
6.
J Laparoendosc Adv Surg Tech A ; 32(7): 787-793, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35575748

RESUMEN

Background and Aims: Duodenal endoscopic submucosal dissection (ESD) has been considered to be the most challenging because of its high incidence of complications, which has hindered the development of duodenal ESD. The aim of this study is to discuss operation tips for duodenal ESD and to assess the efficacy and safety of duodenal ESD. Patients and Methods: Eighty-two patients who underwent ESD in the digestive endoscope center for superficial duodenal epithelial tumors (SDETs) from January 2017 to June 2021 were studied. Patients were divided into three groups according to the occurrence of complications, and the clinical characteristics and surgical efficacy of each group were compared. Results: SDETs in 82 patients were completely removed by ESD, with a 97.5% R0 resection rate. The average size of resected lesions was 23.8 ± 6.5 mm. There were significant differences in lesion size and operation time between the normal and intraprocedural complication groups (P < .05). Similarly, between the normal and delayed complication groups, significant differences were noted in lesion location, size, operation time, occupied circumference, and postoperative hospitalization duration (P < .05). Conclusion: Duodenal ESD is prone to complications that increase the complexity of the procedure. By improving the necessary technique and skills, duodenal ESD remains safe and effective.


Asunto(s)
Neoplasias Duodenales , Resección Endoscópica de la Mucosa , Neoplasias Duodenales/cirugía , Duodeno/cirugía , Resección Endoscópica de la Mucosa/efectos adversos , Resección Endoscópica de la Mucosa/métodos , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
7.
Front Oncol ; 11: 644120, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33854976

RESUMEN

BACKGROUND: Given the reported correlation between the oncogene metastasis-associated in colon cancer 1 (MACC1) and nasopharyngeal carcinoma (NPC), as well as between MACC1 and epithelial-mesenchymal transition (EMT), we speculated that EMT is a likely causative link between MACC1 expression and poor NPC prognosis. Thus, we aim to clarify the relationship between MACC1 and EMT in NPC prognosis. MATERIAL AND METHODS: We performed immunohistochemical examination of tissue sections from 128 NPC patients that were divided into six groups corresponding to high and low protein expression of MACC1 and two EMT-related proteins, vimentin and E-cadherin, and Kaplan-Meier (KM) survival analyses were performed. RESULTS: KM survival analysis showed that upregulation of MACC1 and vimentin and downregulation of E-cadherin were significantly associated with reduced survival in NPC. Short hairpin RNA (shRNA) interference and immunoblotting in the NPC cell line HNE-1 led to increased E-cadherin but decreased vimentin levels. MACC1 overexpression was significantly correlated with poor 5-year overall survival, metastasis-free survival, and disease-free survival (P<0.05) but not with poor relapse-free survival (P>0.05). Univariate analyses revealed that MACC1, E-cadherin, and vimentin levels along with T and N tumor classifications and cancer staging are significant prognostic factors of NPC (P<0.05). CONCLUSION: Our findings showed the association between MACC1 and EMT in NPC malignancy and support the role of MACC1 as a prognostic biomarker and molecular target for NPC treatment.

8.
J Biomol Struct Dyn ; 34(4): 870-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26264861

RESUMEN

Cyclosporine (CsA) is widely used in organ transplant patients to help prevent the patient's body from rejecting the organ. CsA has been shown to be a safe and highly effective immunosuppressive drug that binds with the protein Cyclophilin A (CypA) at active sites. However, the exact mechanism of this binding at the molecular level remains unknown. In this project, we elucidate the binding of CsA to CypA at the molecular level by computing their electron structures and revealing their interactions. We employ a novel technique called electron Computer-Aided Drug Design (eCADD) on the protein's full electron structure along with its hydrophobic pocket and the perturbation theory of the interaction between two wave functions. We have identified the wave function of CypA, the biological active residues and active atoms of CypA and CsA, the interaction site between CypA and CsA, and the hydrogen bonds in the ligand CsA binding site. All these calculated active residues, active atoms, and hydrogen bonds are in good agreement with recorded laboratory experiments and provide guidelines for designing new ligands of CypA. We believe that our eCADD framework can provide researchers with a cost-efficient new method of drug design based on the full electron structure of proteins.


Asunto(s)
Ciclofilina A/química , Electrones , Modelos Moleculares , Estructura Molecular , Sitios de Unión , Dominio Catalítico , Ciclofilina A/metabolismo , Diseño de Fármacos , Enlace de Hidrógeno , Ligandos , Simulación de Dinámica Molecular , Unión Proteica , Relación Estructura-Actividad
9.
J Biomol Struct Dyn ; 33(2): 388-94, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24471694

RESUMEN

We present a study of FKBP12/FK506 using an electron structure calculation. These calculations employ a novel technique called eCADD on the protein's full electron structure along with its hydrophobic pocket and the frontier-orbital-perturbation theory. We first obtain the energy bands and orbital coefficients of protein FKBP12. On this basis, we found that the activity atoms and activity residues of FKBP12 were in good agreement with X-ray crystallography experiments. The results indicate that the interactions occur only between the LUMOs of FKBP12 and the HOMO of FK506, not between the HOMOs of FKBP12 and the LUMO of FK506. In other words, the activity sites of protein FKBP12 are located on its LUMOs, not HOMOs. The electron structures of FKBP12/FK506 give us a clearer understanding of their interaction mechanism and will help us design new ligands of FKBP12.


Asunto(s)
Inmunosupresores/química , Proteína 1A de Unión a Tacrolimus/química , Tacrolimus/química , Secuencias de Aminoácidos , Sitios de Unión , Humanos , Simulación de Dinámica Molecular , Unión Proteica , Estructura Terciaria de Proteína , Termodinámica
10.
Eur J Med Chem ; 46(5): 1701-5, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21396746

RESUMEN

Through virtual screening of a rationally built database consisting of 40 peptides, we identified three short peptides. After testing these three synthetic peptides, we found that the peptide Trp-Gly-Pro (WGP) showed comparable inhibitory ability as positive control cyclosporine A (CsA) on CypA-mediated PPIase activity with IC50 values of 33.11 nM and 10.25 nM, respectively. The peptide WGP had same order of CypA-binding affinity as CsA with dissociation equilibrium constant KD of 3.41×10(-6) and 6.42×10(-6) M, respectively. This peptide could also inhibit HIV-1IIIB infection. This study provides a novel strategy for rational design and development of peptidic drugs.


Asunto(s)
Ciclofilina A/antagonistas & inhibidores , Descubrimiento de Drogas , Oligopéptidos/farmacología , Sitios de Unión/efectos de los fármacos , Línea Celular Transformada , Ciclofilina A/metabolismo , Relación Dosis-Respuesta a Droga , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Humanos , Modelos Moleculares , Oligopéptidos/síntesis química , Oligopéptidos/química , Relación Estructura-Actividad , Replicación Viral/efectos de los fármacos
11.
J Comput Biol ; 17(8): 1081-93, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20726794

RESUMEN

This article presents a mathematical model on the design of peptide inhibitors for proteins. This model is a combination of the two rules on protein-ligand interaction, Miyazawa-Jernigan (M-J) matrix and hidden Markov model (HMM). The model is applied to predict peptide inhibitors for the protein cyclophilin A (CypA) and FKBP12, and then validated by the highest occupied molecular orbital calculation, dock process between protein and inhibitor, and biological experiments. The results are encouraging and suggest that we have taken a step forward towards building a mathematical theory on the design of peptide inhibitors for proteins. The mathematical model is rough at present, but if it represents a correct direction of the theoretical trends of biology as we believe, then this theory can be further developed and become more and more precise.


Asunto(s)
Péptidos/química , Péptidos/farmacología , Proteínas/antagonistas & inhibidores , Ciclofilina A/antagonistas & inhibidores , Ciclofilina A/metabolismo , Ligandos , Cadenas de Markov , Modelos Biológicos , Modelos Moleculares , Unión Proteica , Proteínas/metabolismo , Proteína 1A de Unión a Tacrolimus/antagonistas & inhibidores , Proteína 1A de Unión a Tacrolimus/metabolismo
12.
J Biomol Struct Dyn ; 23(6): 603-12, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16615806

RESUMEN

The quasielastic neutron scattering index beta and the modulus of a protein's quasi-electric dipole moment were utilized to quantitate the thermostability of wildtype TC23O and its mutants. Charged residues Arg314, Glu246, Glu291, and some prolines near the C-terminus of the sequence (Pro228, Pro296, and Pro308) were identified to be critical for the thermostability of wildtype TC23O according to these two criteria. By analyzing the molecular conformation changes during the simulation, it was demonstrated how the mutant P228S was destabilized by disrupting two salt-bridges Asp116OD1-Lys215N and Glu210OE1-Lys217N at an adjacent beta-turn. The destabilization of P296S also shown to be intimate correlated with the break down of ion pair Lys188N-Glu291OE1. The sensitivity of its electrostatic network to the local structure is an important feature. It reveals that the 'proline effect' and electrostatic interactions together influences the thermostability of TC23O a lot.


Asunto(s)
Catecol 2,3-Dioxigenasa/química , Simulación por Computador , Modelos Moleculares , Dioxigenasas/química , Estabilidad de Enzimas , Conformación Proteica , Pirazoles/química , Electricidad Estática , Termodinámica
13.
J Biomol Struct Dyn ; 21(5): 657-62, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-14769058

RESUMEN

The thermostability of protein thermostable cathechol 2,3-dixoygenase (TC23O) has been studied by the parallel molecular dynamics simulations. By analysis of the exponent beta, which is related to the scattering spectrum and constant-pressure heat capacity Cp, we reveal the respective contribution of a specific residue 228 proline; a specific salt bridge, Lys188N-Glu291OE1; four ions; and a different water environment to the thermostability of TC23O. The dynamic transition temperature of the mutants, Pro228Ser and Glu291Gly of the TC23O, was decreased about 10 degrees C and 19 degrees C respectively. The displacement of the four ions had no significant effect on the thermostability of TC23O. Water affects the thermostability by influencing the changes of accessible conformation to a certain extent. All these results agree with the known experimental results.


Asunto(s)
Dioxigenasas , Calor , Oxigenasas/química , Catecol 2,3-Dioxigenasa , Interpretación Estadística de Datos , Cinética , Modelos Moleculares
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