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1.
J Cancer Res Clin Oncol ; 150(2): 98, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38381215

RESUMEN

OBJECTIVE: The initial therapeutic approach for diffuse large B-cell lymphoma (DLBCL) entails a rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) regimen. However, 40% of patients exhibit suboptimal responses, with some experiencing relapse and refractory conditions. This study aimed to explore novel therapeutic strategies and elucidate their underlying mechanisms in DLBCL. METHODS: Bioinformatics techniques were employed to scrutinize correlations between the HDAC1, HDAC2, HDAC3, HDAC10, BTK, MYC, TP53, and BCL2 genes in DLBCL. In vitro experiments were conducted using DB and SU-DHL-4 cells treated with chidamide, orelabrutinib, and a combination of both. Cell viability was assessed by cell counting kit-8. Cell apoptosis and the cell cycle were determined using flow cytometry. Reactive oxygen species (ROS) production and mitochondrial function were assessed through ROS and JC-1 staining. RNA sequencing and western blot analyses were conducted to elucidate the molecular mechanisms underlying the combined action of chidamide and orelabrutinib in DLBCL cells. RESULTS: This investigation revealed markedly enhanced antiproliferative effects when chidamide was combined with orelabrutinib. Compusyn software analysis indicated a synergistic effect of chidamide and orelabrutinib in inhibiting DLBCL cell proliferation, with a combination index (CI) < 1. This synergy further manifested as augmented cell cycle arrest, apoptosis induction, the downregulation of cell cycle-associated and antiapoptotic proteins, and the upregulation of proapoptotic proteins. Furthermore, the western blot and RNA-Seq findings suggested that combining chidamide and orelabrutinib modulated the PI3K/AKT/mTOR signaling pathway, thereby promoting DLBCL cell cycle arrest and apoptosis. CONCLUSION: The findings of this study provide a compelling justification for the clinical utilization of chidamide and orelabrutinib to treat relapsed/refractory DLBCL.


Asunto(s)
Aminopiridinas , Benzamidas , Linfoma de Células B Grandes Difuso , Fosfatidilinositol 3-Quinasas , Piperidinas , Piridinas , Humanos , Proteínas Proto-Oncogénicas c-akt , Especies Reactivas de Oxígeno , Recurrencia Local de Neoplasia , Apoptosis , Puntos de Control del Ciclo Celular , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/genética , Serina-Treonina Quinasas TOR , Histona Desacetilasas
2.
Nanoscale ; 10(46): 21703-21711, 2018 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-30431037

RESUMEN

Promoting surface strains in heterogeneous catalysts and heteroatomic interactions in alloying offer an effective strategy for the development of electrocatalysts with greatly enhanced activity. In this work, we design platinum-silver nanotubes (PtAg NTs) with tunable surface compositions by a controlled galvanic replacement reaction of well-defined Ag nanowires (NWs). The optimized and porous PtAg NTs (PtAg-4 NTs), with the Pt5Ag3 surface composition and (111) facet-dominant surface features, exhibit an extraordinary oxygen reduction reaction (ORR) activity that reaches a specific activity of 1.13 mA cm-2 and a mass activity of 0.688 A mg-1Pt at 0.9 V versus a reversible hydrogen electrode (RHE), which are 4.5 times and 4.3 times those of commercial Pt/C catalysts (0.25 mA cm-2 and 0.16 A mg-1Pt). Moreover, PtAg-4 NTs/C can endure under the ORR conditions over the course of 10 000 cycles with negligible activity decay. Remarkably, density functional theory simulations reveal that the porous PtAg-4 NTs exhibit enhanced adsorption interaction with adsorbates, attributed to the catalytically active sites on high-density (111) facets and modulation of the surface strain, further boosting the ORR activity and durability.

3.
Chem Asian J ; 12(12): 1272-1276, 2017 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-28406550

RESUMEN

The development of a facile strategy for conversion of graphene quantum dots (GQDs) into crystalline graphite is of great practical significance and still remains challenging. Herein, rationally assembled crystalline-intercrossed graphite nanocapsules (CI-GNCs) have been realized by a one-step electrochemically induced strategy with the assistance of a soft template, in which the GQDs act as the initial building blocks. The as-prepared CI-GNCs exhibit highly crystalline graphitic nanostructures. Moreover, they possess promising electrocatalytic activity for the oxygen reaction reduction (ORR) in alkaline medium. This simple fabrication technology presents a great advance for synthesizing CI-GNCs composite catalysts, which have potential as new metal-free catalysts for efficient ORR applications.

4.
Adv Mater ; 28(17): 3305-12, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26932679

RESUMEN

Functional graphene bulks are developed by a general and simple approach for largescale preparation. This method shows promise for energy-related applications.

5.
J Phys Chem A ; 110(3): 944-50, 2006 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-16419994

RESUMEN

The potential energy surfaces of isomerization, dissociation, and elimination reactions for CH3CH2COCl in the S0 and S1 states have been mapped with the different ab initio calculations. Mechanistic photodissociation of CH3CH2COCl at 266 nm has been characterized through the computed potential energy surfaces, the optimized surface crossing structure, intrinsic reaction coordinate, and ab initio molecular dynamics calculations. Photoexcitation at 266 nm leads to the CH3CH2COCl molecules in the S1 state. From this state, the C-Cl bond cleavage proceeds in a time scale of picosecond in the gas phase. The barrier to the C-Cl bond cleavage on the S1 surface is significantly increased by effects of the matrix and the internal conversion to the ground state prevails in the condensed phase. The HCl eliminations as a result of internal conversion to the ground state become the dominant channel upon photodissociation of CH3CH2COCl in the argon matrix at 10 K.

6.
Luminescence ; 21(1): 20-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16078306

RESUMEN

A simple electrogenerated chemiluminescence (ECL) analysis method for the determination of norfloxacin (NFLX) is reported. It is based on ECL produced by Na(2)SO(3), which is sensitized by the Tb-NFLX complex. The relative ECL intensity of the Tb(3+)-NFLX-Na(2)SO(3) system is proportional to the amount of NFLX. The optimized experimental conditions were investigated. The linear range and detection limit for NFLX were 1.0 x 10(-10)-8.0 x 10(-7) mol/L and 2.8 x 10(-11) mol/L, respectively. This method was successfully applied to the determination of NFLX in a capsule. NFLX in urine can be directly detected without pretreatment or separation.


Asunto(s)
Antibacterianos/química , Mediciones Luminiscentes/métodos , Norfloxacino/química , Terbio/química , Sulfatos/química
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 64(1): 130-5, 2006 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-16098798

RESUMEN

The electrochemiluminescence (ECL) of Tb3+-enoxacin-Na2SO3 system (ENX system) and Tb3+-ofloxacin-Na2SO3 system (OFLX system) in aqueous solution is reported. ECL is generated by the oxidation of Na2SO3, which is enhanced by Tb3+-fluoroquinolone (FQ) complex. The ECL intensity peak versus potential corresponds to oxidation of Na2SO3, and the ECL emission spectra (the peaks are at 490, 545, 585 and 620 nm) match the characteristic emission spectrum of Tb3+, indicating that the emission is from the excited state of Tb3+. The mechanism of ECL is proposed and the difference of ECL intensity between ENX system and OFLX system is explained. Conditions for ECL emission were optimized. The linear range of ECL intensity versus concentrations of pharmaceuticals is 2.0 x 10(-10) -8.0 x 10(-7)mol l(-1) for ENX and 6.0 x 10(-10) -6.0 x 10(-7)mol l(-1) for OFLX, respectively. A theoretical limit of detection is 5.4 x 10(-11)mol l(-1) for ENX and 1.6 x 10(-10)mol l(-1) for OFLX, respectively. The ECL was satisfactorily applied to the determination of the two FQs in dosage form and urine sample.


Asunto(s)
Enoxacino/química , Luminiscencia , Ofloxacino/química , Sulfitos/química , Terbio/química , Electroquímica , Soluciones , Agua/química
8.
Anal Sci ; 21(4): 373-5, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15844328

RESUMEN

A novel method for determination of trace amounts of tosufloxacin (TFLX) based on electrochemiluminescence (ECL) has been developed. The calibration graphs for TFLX were linear in the range of 5.0 x 10(-11)-3.5 x 10(-7) mol/L, with the detection limit of 1.3 x 10(-11) mol/L. Key factors affecting the determination of TFLX were investigated. TFLX amounts in capsule and serum samples were successfully detected by this method. A possible mechanism of energy transfer, and thus the explanation of ECL in the Tb3+-TFLX-Na2S2O4 system are discussed.


Asunto(s)
Antibacterianos/análisis , Fluoroquinolonas/análisis , Naftiridinas/análisis , Terbio/química , Calibración , Cápsulas , Electroquímica , Concentración de Iones de Hidrógeno , Indicadores y Reactivos , Mediciones Luminiscentes , Espectrofotometría Ultravioleta
9.
Anal Sci ; 20(7): 1075-8, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15293405

RESUMEN

A simple, rapid and highly sensitive fluorometric method for the determination of pazufloxacin mesilate (PZFX) is described. It is based on the formation of the complex [Tb(PZFX)2](3+), which shows the intensive characteristic bands of Tb3+. Optimum conditions for the determination were investigated. Under the optimum experimental condition, the fluorescence intensity responds linearly to the PZFX concentration in the range of 2.0 x 10(-8) - 5.0 x 10(-6) mol/l with a detection limit of 6.2 x 10(-9) mol/l. The method has been successfully applied to the determination of PZFX in urine and serum samples.


Asunto(s)
Antibacterianos/farmacocinética , Fluoroquinolonas/análisis , Oxazinas/análisis , Espectrometría de Fluorescencia/métodos , Terbio/análisis , Antibacterianos/análisis , Antituberculosos/análisis , Calibración , Fluoroquinolonas/farmacocinética , Humanos , Concentración de Iones de Hidrógeno , Modelos Químicos , Oxazinas/farmacocinética , Sensibilidad y Especificidad , Orina
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 59(11): 2541-6, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12963449

RESUMEN

A novel flow injection chemiluminescence (CL) system is developed to determine DNA. According to the fact that DNA linearly quenches the CL intensity of Ce(IV)-Na(2)SO(3)-Tb(III)-fluoquinolone antibiotic (FLUQ) system, DNA concentration is determined. The calibration graphs are linear in the range of 0.04-10 microg/ml (for both natural and denatured DNA), and the 3sigma limits of detection are 7.8 ng/ml (natural DNA) and 9.5 ng/ml (denatured DNA). According to fluorescence spectrum and CL spectrum, and through studying the reaction of Ce(IV)-Na(2)SO(3)-Tb(III)-FLUQ with nucleotides and bases, we conclude that DNA counteracts the energy transfer from FLUQ to Tb(III), and this function is related to both bases and phosphate groups in DNA.


Asunto(s)
Cerio/química , ADN/química , Fluoroquinolonas/química , Sulfatos/química , Sulfitos/química , Terbio/química , Cerio/metabolismo , ADN/metabolismo , Análisis de Inyección de Flujo , Mediciones Luminiscentes , Sondas Moleculares , Terbio/metabolismo
11.
Talanta ; 61(3): 403-9, 2003 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-18969200

RESUMEN

A simple, rapid and sensitive method for the determination of two fluoquinolones (FQs), enoxacin (ENX) and ofloxacin (OFLX) is described by using flow injection analysis with potassium permanganate-sodium sulfite chemiluminescence detection. The calibration graphs for ENX and OFLX are linear in the range of 8.0x10(-10)-1.0x10(-5) and 1.0x10(-9)-1.0x10(-6) mol l(-1), respectively. The 3sigma limits of detection are 2.4x10(-10) mol l(-1) for ENX and 5.6x10(-10) mol l(-1) for OFLX. The method is applied satisfactorily to the determination of the two FQs in dosage form and urine sample. The possible mechanism is also proposed.

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