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1.
Front Oncol ; 13: 1239451, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38205138

RESUMEN

Background: The emergence of immune checkpoint inhibitors (ICIs) has brought about a paradigm shift in the treatment landscape of non-small cell lung cancer (NSCLC). Despite the promising long-term survival outcomes and optimization of pathological complete response (cPR) demonstrated by various studies such as Impower010 and Checkmate-816, the effectiveness of neoadjuvant immunotherapy in advanced resectable NSCLC remains a subject of debate. Although previous research has explored the connection between the efficacy of neoadjuvant therapy and surgical-related safety, limited studies have specifically investigated the surgical-related safety of neoadjuvant immunotherapy. Therefore, our study aims to assess the efficacy and surgical-related safety of neoadjuvant immunotherapy in advanced resectable non-small cell lung cancer. Method: We conducted a retrospective study on a cohort of 93 patients with stage IIIA-IIIC NSCLC who underwent neoadjuvant therapy and surgical resection. Among them, 53 patients received neoadjuvant immunotherapy, 18 patients underwent neoadjuvant chemotherapy while the remaining 22 underwent neoadjuvant targeted therapy. The patients were separated into further groups according to their pathological type. Data analyses were performed using Mann-Whitney U test, chi-square test. Results: All patients were categorized into six distinct groups. Notably, the neoadjuvant immunotherapy squamous carcinoma group exhibited a favorable edge over the neoadjuvant targeted squamous carcinoma group concerning the duration of drainage tube indwelling and the extent of lymph node dissection. Furthermore, the neoadjuvant immunotherapy adenocarcinoma group outperformed neoadjuvant targeted therapy adenocarcinoma counterpart in terms of achieving complete pathological response (cPR). Simultaneously, the neoadjuvant immunotherapy adenocarcinoma group surpassed the neoadjuvant chemotherapy adenocarcinoma group in the incidence of hydrothorax. Nevertheless, no statistically significant disparities were noted between the neoadjuvant immunotherapy squamous carcinoma group and the neoadjuvant chemotherapy carcinoma group. Conclusion: Regarding surgical outcomes, neoadjuvant immunotherapy conferred notable advantages compared to conventional neoadjuvant chemotherapy and neoadjuvant targeted therapy for patients diagnosed with adenocarcinoma. In the case of squamous carcinoma, neoadjuvant immunotherapy exhibited superiority over neoadjuvant targeted therapy, although additional evidence is required to conclusively establish its precedence over neoadjuvant chemotherapy.

2.
Anal Chem ; 90(18): 10803-10811, 2018 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-30129747

RESUMEN

This work reports the first synthesis and characterization of a ferroelectric perovskite oxide-based heterostructure as well as its application for photoelectrochemical (PEC) bioanalytical purposes. Specifically, exemplified by [KNbO3]1- x[BaNi1/2Nb1/2O3-δ] x (KBNNO), the ferroelectric perovskite oxides were prepared by solid-state synthesis, while the TiO2 nanorod (NR) arrays were obtained via a hydrothermal method. Using the technique of pulsed laser deposition (PLD), KBNNO were then deposited on TiO2 NRs to form KBNNO@TiO2 NR heterostructures. Various characterization techniques were applied to reveal compositional and structural information on the as-fabricated sample, and favorable alignment existed between the two components as displayed by the PEC test. In the detection of l-cysteine, the as-fabricated KBNNO@TiO2 NRs demonstrated good performance in terms of sensitivity and selectivity. This work revealed the potential of ferroelectric perovskite oxide and its heterostructures for innovative PEC bioanalytical applications, and we hope it will generate more interest in the development of various ferroelectrics-based heterostructures for advanced PEC bioanalysis.


Asunto(s)
Compuestos de Calcio/química , Técnicas Electroquímicas/métodos , Compuestos Ferrosos/química , Nanotubos/química , Óxidos/química , Procesos Fotoquímicos , Titanio/química , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Espectrometría Raman , Difracción de Rayos X
3.
Biosens Bioelectron ; 39(1): 210-4, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-22884003

RESUMEN

A direct electrochemical DNA biosensor based on zero current potentiometry was fabricated by immobilization of ssDNA onto gold nanoparticles (AuNPs) coated pencil graphite electrode (PGE). One ssDNA/AuNPs/PGE was connected in series between clips of working and counter electrodes of a potentiostat, and then immersed into the solution together with a reference electrode, establishing a novel DNA biosensor for specific DNA detection. The variation of zero current potential difference (ΔE(zcp)) before and after hybridization of the self-assembled probe DNA with the target DNA was used as a signal to characterize and quantify the target DNA sequence. The whole DNA biosensor fabrication process was characterized by cyclic voltammetry and electrochemical impedance spectroscopy with the use of ferricyanide as an electrochemical redox indicator. Under the optimized conditions, ΔE(zcp) was linear with the concentrations of the complementary target DNA in the range from 10nM to 1µM, with a detection limit of 6.9nM. The DNA biosensor showed a good reproducibility and selectivity. Prepared DNA biosensor is facile and sensitive, and it eliminates the need of using exogenous reagents to monitor the oligonucleotides hybridization.


Asunto(s)
Técnicas Biosensibles/instrumentación , ADN/análisis , Hibridación de Ácido Nucleico , Potenciometría/instrumentación , Secuencia de Bases , Sondas de ADN/química , Diseño de Equipo , Oro/química , Grafito/química , Sensibilidad y Especificidad
4.
Talanta ; 85(5): 2620-5, 2011 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-21962692

RESUMEN

In this paper, gold nanoparticle-thionine-reduced graphene oxide (GNP-THi-GR) nanocomposites were prepared to design a label-free immunosensor for the sensitive detection of carcinoembryonic antigen (CEA). The nanocomposites with good biocompatibility, excellent redox electrochemical activity and large surface area were coated onto the glassy carbon electrode (GCE) surface and then CEA antibody (anti-CEA) was immobilized on the electrode to construct the immunosensor. The morphologies and electrochemistry of the formed nanocomposites were investigated by using scanning electron microscopy (SEM), ultraviolet-visible (UV-vis) spectrometry, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). CV and differential pulse voltammetry (DPV) studies demonstrated that the formation of antibody-antigen complexes decreased the peak current of THi in the GNP-THi-GR nanocomposites. The decreased currents were proportional to the CEA concentration in the range of 10-500 pg/mL with a detection limit of 4 pg/mL. The proposed method was simple, fast and inexpensive for the determination of CEA at very low levels.


Asunto(s)
Técnicas Biosensibles , Antígeno Carcinoembrionario/análisis , Electroquímica/instrumentación , Electrodos , Oro , Grafito/química , Nanopartículas del Metal , Microscopía Electrónica de Rastreo , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta
5.
Inorg Chem ; 50(11): 4967-77, 2011 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-21526757

RESUMEN

Density functional theory calculations have been carried out to investigate α-, ß-, γ-, α*-, ß*-, and γ*-[(PO(4))(2)W(18)O(54)](6-) Wells-Dawson isomers, which exhibited stability in the order of α > ß > γ > γ* > ß* > α*, reproduced the experimental observations (α > ß > γ), and confirmed the hypothesis of Contant and Thouvenot (γ* > ß* > α*). Energy decomposition analysis reveals that both the spatial arrangement of the host W(18)O(54) cage (eclipsed or staggered) and its structural distortion induced by the encapsulated guest anions are two dominant factors in control of the stability order, while the influences of host-guest interaction and distortion of the guest anions are very small. A building block decomposition approach is designed and provides an effective means to clarify the detailed relationship between the local distortion and energy. By using this method, it is found that the eclipsed belt, and in particular the staggered belt, significantly distort the two caps inside the Wells-Dawson structure. Notably, there is a direct relationship between the overall stability and distortion in the belts, which is proven to be partly originating from the dominance in the quantity of the belt building blocks over that of the caps (12:6). Besides, half-unit {XW(9)} decomposition confirms that [(XO(4))(2)W(18)O(54)](n-) (X = Si, Ge, Al, and Ga) are thermodynamically instable because of the notable electrostatic repulsion between two {XW(9)} units induced by the highly charged guest anions.


Asunto(s)
Teoría Cuántica , Compuestos de Tungsteno/química , Aniones/química , Modelos Moleculares , Estereoisomerismo , Termodinámica
6.
Inorg Chem ; 49(12): 5472-81, 2010 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-20499855

RESUMEN

Density functional theory calculations have been carried out to investigate the alpha, beta, gamma, delta, and epsilon isomers of [(MnO(4))Me(12)Sb(12)O(24)](6-) (Me = CH(3)) anions, which are simplified Baker-Figgis models of Keggin-type antimonate complexes in experiments. It is found that the stability order of the five isomers (alpha < beta < gamma < delta < epsilon) perfectly reverses to the well-known trend of the classical Keggin [PW(12)O(40)](3-) anions (alpha > beta > gamma > delta > epsilon), despite their significant similarities in frameworks. On the basis of the building block decomposition method, the stabilizing effect of the edge-sharing [Sb(2)(mu-O)(2)Me(2)] fragment inside gamma, delta, and epsilon structures is confirmed and found to originate from its two energy-favorable components rather than itself as an indivisible unit. Similar behavior is also held by the destabilizing [W(2)(mu-O)(2)O(2)] fragment in [PW(12)O(40)](3-); however, the well-accepted electrostatic repulsion between the short W(VI)-W(VI) contacts cannot be taken as direct evidence. Notably, in the assembly of the [(MnO(4))Me(12)Sb(12)O(24)](6-) structure, all of the octahedral building units incline to compress axially and elongate horizontally, and this is exactly opposite to the deformation pattern observed in the building blocks of Keggin tungstates, which tend to elongate axially and compress horizontally, thus giving rise to the inverted stability order. Furthermore, energy decomposition analysis reveals that the intrinsic property of the anion comes from the spatial arrangements of the metal-oxygen cage and does not change significantly with the type and charge of the encapsulated anion.


Asunto(s)
Antimonio/química , Simulación por Computador , Manganeso/química , Modelos Químicos , Compuestos Organometálicos/química , Teoría Cuántica , Isomerismo , Modelos Moleculares , Estructura Molecular , Estereoisomerismo
7.
Yao Xue Xue Bao ; 43(1): 86-90, 2008 Jan.
Artículo en Chino | MEDLINE | ID: mdl-18357739

RESUMEN

To develop a method for the detection of surface-confined peptides containing cysteine residues or oligodeoxynucleotides (ODNs) whose 3' ends modified with thiol groups, and a thiol-specific fluorescent cross-linker, N-(9-acridinyl) maleimide (NAM) was used. The peptides studied herein include both the oxidized and reduced forms of glutathione, and a hexapeptide (FT). Peptides are first attached onto the activated 11-mercaptoundecanoic acid (MUA)-terminated alkanethiol self-assembled monolayers (SAMs) and then derivatized with NAM. The cysteine residues was determined by using electrochemical desorption and fluorescence detection. GSH concentration as low as 40 pmol x L(-1) can be measured. The fluorescence intensity in the case of FT is about 3 times as high as that for GSH, which is consistent with the molar ratio of cysteine residues in these two molecules. The analytical performance of gene analysis was also evaluated through the analyses of a complementary target and targets with varying numbers of mismatching bases. The method described here is simple, sensitive, reproducible, and does not require sophisticated analytical instrumentation and separation procedures.


Asunto(s)
Cisteína/análisis , Electroquímica/métodos , Glutatión/química , Oligodesoxirribonucleótidos/análisis , Técnicas Biosensibles/métodos , Fluorescencia , Glutatión/análisis , Maleimidas/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): m413, 2008 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-21201359

RESUMEN

In the crystal structure of the title compound, {[Fe(2)(C(7)H(3)NO(4))(2)(H(2)O)(6)]·4H(2)O}(n), there are two types of coordination for the Fe(II) atoms. One Fe(II) atom is in a distorted octa-hedral N(2)O(4) environment, with two chelating rings from the pyridine-dicarboxyl-ate ligands and two O atoms from the water mol-ecules, while the other is in a distorted octa-hedral O(6) environment with two O atoms from the pyridine-dicarboxyl-ate ligands and four O atoms from the water mol-ecules. Both Fe(II) atoms lie on crystallographic centers of symmetry. The complex possesses an infinite chain structure running along the [101] direction. These chains are inter-connected by the uncoordinated water mol-ecules through O-H⋯O hydrogen bonds.

9.
Yao Xue Xue Bao ; 40(8): 750-3, 2005 Aug.
Artículo en Chino | MEDLINE | ID: mdl-16268512

RESUMEN

AIM: To establish a polarographic method of parallel catalytic hydrogen wave for determination of glimepiride. METHODS: The catalytic wave of glimepiride in the presence of K2S2O8 was used to improve the analytical sensitivity. The rapid determination of glimepiride was done by linear single sweep polarography. RESULTS: The catalytic hydrogen wave of glimepiride was measured at ca. -1.36 (vs SCE) in 0.09 mol x L(-1) Na2B4O7-KH2PO4 (pH 6.24 +/- 0.1) supporting electrolyte. When 1.0 x 10(-2) mol x L(-1) K2S2O8 was present, the current increased by 25 times, and the peak potentioal was unchanged, producing a more sensitive parallel catalytic hydrogen wave. The peak current of the parallel catalytic hydrogen wave was rectilinear to the glimepiride concentration in the range 1.0 x 10(-7) - 4.2 x 10(-5) mol x L(-1) (r = 0.9990, n = 9). The detection limit was 5.0 x 10(-8) mol x L(-1). CONCLUSION: The proposed method could be applied to the determination of glimepiride in pharmaceuticals without preliminary separation.


Asunto(s)
Polarografía/métodos , Compuestos de Sulfonilurea/análisis , Catálisis , Humanos , Hipoglucemiantes/análisis , Hipoglucemiantes/orina , Masculino , Compuestos de Potasio/análisis , Sulfatos/análisis , Compuestos de Sulfonilurea/orina
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(11): 1407-9, 2004 Nov.
Artículo en Chino | MEDLINE | ID: mdl-15762489

RESUMEN

Benzoic acid with weak fluorescence may react on *OH, and then products with intense fluorescence are made. Extractives of Chinese traditional medicine may eliminate *OH in solution, and reduce the amounts of the products. Then, the increased level of fluorescence of the products in solution will be lowered. Based on this principle, a novel catalysis kinetics fluorimetry system for the determination of eliminating ratio of Chinese traditional medicine for *OH was developed. When the concentration of traditional Chinese herbal drugs was 4.0 mg (dry weight) x mL(-1), the eliminating ratios of Viola yedoensis, Atrctylodes chinensis and Paeonia veitchii were 60.8%, 40.1% and 94.3%, respectively. The results obtained by this method are in good agreement with those obtained by spectrophotometry.


Asunto(s)
Ácido Benzoico/química , Catálisis , Medicamentos Herbarios Chinos/análisis , Fluorometría/métodos , Diagnóstico Diferencial , Medicamentos Herbarios Chinos/química , Radicales Libres , Cinética , Medicina Tradicional China
11.
Yao Xue Xue Bao ; 39(10): 821-5, 2004 Oct.
Artículo en Chino | MEDLINE | ID: mdl-15700824

RESUMEN

AIM: To develop a new method for the determination of clarithromycin. METHODS: The catalytic wave of clarithromycin in the presence of K2S2O8 was used for improving the analytical sensitivity. The rapid determination of clarithromycin has been carried out by linear single sweep polarography. RESULTS: The reduction wave of clarithromycin appeared at ca. -0.79 V (vs SCE) in 0.24 mol x L(-1) KH2PO4-Na2HPO4 (pH 6.81) supporting electrolyte, which was ascribed to the reduction of carbonyl group on C-9 position. In the presence of 0.01 mol x L(-1) K2S2O8, the reduction wave was catalyzed to produce a parallel catalytic wave. The peak current of the catalytic wave was ca. Twenty times higher than that of the corresponding reduction wave. Based on the catalytic wave, a new method for the determination of clarithromycin has been proposed. The peak current of the catalytic wave was rectilinear to clarithromycin concentration in the range of 4.0 x 10(-7)-5.0 x 10(-5) mol x L(-1). The detection limit was 2.0 x 10(-7) mol x L(-1). CONCLUSION: The proposed method could be used for the direct determination of clarithromycin in pharmaceuticals and urine without preliminary separation.


Asunto(s)
Claritromicina/análisis , Polarografía/métodos , Antibacterianos/análisis , Antibacterianos/química , Catálisis , Claritromicina/química , Concentración de Iones de Hidrógeno , Compuestos de Potasio/química , Sulfatos/química
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