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1.
Biomater Sci ; 12(7): 1630-1642, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38404259

RESUMEN

To meet the demand for precision medicine, researchers are committed to developing novel strategies to reduce systemic toxicity and side effects in cancer treatment. Targeting peptides are widely applied due to their affinity and specificity, and their ability to be high-throughput screened, chemically synthesized and modified. More importantly, peptides can form ordered self-assembled structures through non-covalent supramolecular interactions, which can form nanostructures with different morphologies and functions, playing crucial roles in targeted diagnosis and treatment. Among them, in targeted immunotherapy, utilizing targeting peptides to block the binding between immune checkpoints and ligands, thereby activating the immune system to eliminate cancer cells, is an advanced therapeutic strategy. In this mini-review, we summarize the screening, self-assembly, and biomedical applications of targeting peptide-based nanomaterials. Furthermore, this mini-review summarizes the potential and optimization strategies of targeting peptides.


Asunto(s)
Nanoestructuras , Neoplasias , Péptidos/química , Nanoestructuras/química , Medicina de Precisión , Neoplasias/tratamiento farmacológico , Neoplasias/diagnóstico
2.
ACS Omega ; 7(48): 43531-43547, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36506165

RESUMEN

The Zhuozishan coalfield at the western margin of the Ordos Basin is one of the main coal-mining areas in China, and recent explorations have revealed the great potential for coalbed methane (CBM) resources in its Carboniferous and Permian strata. In this paper, the controlling factors of CBM enrichment of the major coals are studied in this coalfield and the CBM resources are estimated based on the analysis of the coal petrology and compilation of literature data on the gas content. The result of the coal petrology analysis of 10 samples shows that the vitrinite content of No. 16 coal (71.9-77.3%) is higher than that of No. 9 coal (59.1-65.1%), and the inertinite content of No. 16 coal (18.9-23.5%) is lower than that of No. 9 coal (30.1-34.9%). The R o,max value of No. 16 coal (1.18-1.35%) is higher than that of No. 9 coal (1.04-1.13%), and both coals are of medium rank. Due to greater thickness, deeper burial depth, and better coal petrology characteristics, the No. 16 coal seam of the Taiyuan Formation is selected as the major coal seam for CBM resource estimation, which has a thickness of 1-6 m and a present-day burial depth of 200-1100 m. The gas content of this coal seam varies mostly between 4 and 10 m3/t. Positive correlation between the coal seam thickness as well as present-day burial depth and the gas content suggests that the thick and deeply buried coal seams are favorable for CBM preservation. The ash yield shows an insignificant negative correlation with the gas content, indicating that ash yield is not an important factor for CBM enrichment. The syncline hinges located below the thrust zones show higher gas content due to greater burial depths. In contrast, the anticline hinges at shallower depths tend to have lower gas contents. Based on the combined information about sedimentary environments, structural patterns, and hydrogeology, two CBM accumulation models are put forward in the study area that include syncline-hydraulic plugging below thrust nappe and fault-confined aquifer plugging. The volumetric method is used to estimate the CBM resources, and results indicate that the CBM resource in the whole coalfield is 428.78 × 108 m3, and the total resource abundance is 0.74 × 108 m3/km2. Two favorable areas for the CBM exploration are optimized based on the resource amount and resource abundance. One of the favorable areas is the Kabuqi area in the northern part of the coalfield, and another is the Baiyunwusu area in the central part of the coalfield. These two areas will be the CBM priority exploration areas at the western margin of the Ordos Basin.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 272: 120947, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35144080

RESUMEN

Fly ash (-FA) from seven typical power plants in Shanxi province (North China) were collected to explore the effect of carbon residues (-CR) structures on their burnout characteristic. Burnout characteristic is expressed by the loss on ignition (LOI) content in fly ash. Raman spectroscopy and Fourier Transform infrared (FTIR) spectroscopy are used to characterize the structure of CR. The structure parameters include Raman parameter (the full width at half maxima (FWHM) ratio of D1 and G, ID1/IG) and FTIR parameter (asymmetric stretching intensity ratio of CH2 and CH3 groups, A(CH2)/A(CH3)). Three samples come from circulating fluidized bed (CFB), and four samples are from pulverized coal boilers (PC). Then two types of power plants are numbered from one to three according to the increasing degree of feed coal (-C) metamorphism. The CFB-1-FA, CFB-2-FA, and CFB-3-FA have loss on ignition (LOI) of 9.01%, 16.4%, and 21.6% respectively, while the LOI contents are 1.99%, 4.62%, 23.7%, and 5.00% for the PC-1-FA, PC-2-FA, PC-3-FA, and PC-4-FA. The results show that carbon residues in the PC fly ash mainly have the shorter and branched aliphatic side chains with lower A(CH2)/A(CH3) value. While carbon residues in the CFB fly ash have relatively longer aliphatic chains, and intramolecular aromatization is the main reaction during combustion. The ID1/IG of the CFB carbon residues are generally higher than it for the PC samples, indicating a more ordered structure. Oxygen-deficient environment and the longer residence time at temperature around 900 °C in the CFB boiler promote the ordering progress of the CR. The ordered CR suppresses its burnout and leads to an increase LOI content in fly ash. In turn, sufficient oxygen and temperature around 1200 °C in the PC boiler make the CR further oxidize and decompose. The CR become less ordered and are prone to burn out, resulting in a reduction of the LOI content.


Asunto(s)
Carbono , Espectrometría Raman , Agotamiento Psicológico , Carbón Mineral/análisis , Ceniza del Carbón/análisis , Análisis de Fourier , Espectroscopía Infrarroja por Transformada de Fourier
4.
J Biotechnol ; 341: 146-154, 2021 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-34599994

RESUMEN

Bio-desilication of fly ash containing a large amount of crystalline and amorphous silicate compound by silicate bacteria had the advantages of energy-saving, environment-friendly, and controllable cost. In this study, a bacteria strain with desilication ability on fly ash was isolated from the soil and identified as Bacillus amyloliquefaciens by 16sRNA and named ZGW-12. Through the bio-leaching treatment of fly ash by ZGW-12, it was found that the concentration of Si was 306.26 mg/L and the concentration of Al3+ was 0.5 mg/L in the pulp. The mechanism of bio-leaching using ZGW-12 was investigated by XRD, HPLC, SEM, and FTIR. The organic acid and amino acid in the bacteria culture medium and the pulp were detected, and it was found that the content of the acidic metabolites in the pulp was much larger than that of the bacteria culture medium. The ore sample particles adsorbed a large number of bacteria cells and took place obvious corrosion. The surface of the ore sample undergone hydroxylation reaction, and the diffraction peak of the silicate crystal compound was unchanged. ZGW-12 exhibits good performance in retaining aluminum and extracting silicon aspect. AVAILABILITY OF DATA AND MATERIAL (DATA TRANSPARENCY): All data were true and valid.


Asunto(s)
Bacillus amyloliquefaciens , Metales Pesados , Aluminio , Carbono , Ceniza del Carbón , Suelo
5.
J Phys Chem A ; 124(37): 7340-7345, 2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32786963

RESUMEN

J-aggregates are widely used in studies of light-matter interaction and organic optoelectronic devices. Although J-aggregate films can be fabricated on salt by epitaxial growth method, the size is limited to hundreds of nanometer. In this work, with hexagonal boron nitride (h-BN) as a substrate, highly crystalline J-aggregate ultrathin films of N,N'-ditridecylperylene 3,4,9,10-tetracarboxylic diimide (PTCDI-C13) are achieved by physical vapor transport (PVT) method. Significant bathochromically shifted absorption band and narrowed 0-0 transition are observed in the monolayer PTCDI-C13 crystal on h-BN. The exciton coherence number Ncoh of monolayer J-aggregate film extracted from the photoluminescence (PL) spectrum is up to 15 at T = 140 K, which is higher than that of the epitaxially grown layer on salt. Beyond the first molecular layer, the multilayer crystal on h-BN is dominated by H-aggregates. Further study shows that that the first molecular layer on h-BN adopts the highly ordered face-on configuration, while the overlayers adopt the edge-on motif. As a comparison, only H-aggregate PTCDI-C13 ultrathin films are found on SiO2 substrates, but no J-aggregates. The results suggest that high-quality J-aggregates can be prepared by utilizing appropriate substrates via physical vapor transport.

6.
Antioxidants (Basel) ; 8(11)2019 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-31766125

RESUMEN

Current research has identified S-nitrosoglutathione reductase (GSNOR) as the central enzyme for regulating protein S-nitrosylation. In addition, the dysregulation of GSNOR expression is implicated in several organ system pathologies including respiratory, cardiovascular, hematologic, and neurologic, making GSNOR a primary target for pharmacological intervention. This study demonstrates the kinetic activation of GSNOR by its substrate S-nitrosoglutathione (GSNO). GSNOR kinetic analysis data resulted in nonhyperbolic behavior that was successfully accommodated by the Hill-Langmuir equation with a Hill coefficient of +1.75, indicating that the substrate, GSNO, was acting as a positive allosteric affector. Docking and molecular dynamics simulations were used to predict the location of the GSNO allosteric domain comprising the residues Asn185, Lys188, Gly321, and Lys323 in the vicinity of the structural Zn2+-binding site. GSNO binding to Lys188, Gly321, and Lys323 was further supported by hydrogen-deuterium exchange mass spectroscopy (HDXMS), as deuterium exchange significantly decreased at these residues in the presence of GSNO. The site-directed mutagenesis of Lys188Ala and Lys323Ala resulted in the loss of allosteric behavior. Ultimately, this work unambiguously demonstrates that GSNO at large concentrations activates GSNOR by binding to an allosteric site comprised of the residues Asn185, Lys188, Gly321, and Lys323. The identification of an allosteric GSNO-binding domain on GSNOR is significant, as it provides a platform for pharmacological intervention to modulate the activity of this essential enzyme.

7.
Sci Bull (Beijing) ; 64(22): 1700-1706, 2019 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36659784

RESUMEN

Monolayer molybdenum disulfide (MoS2) is considered to be a promising candidate for field-effect transistors and photodetectors due to its direct bandgap and atomically thin properties. However, the MoS2 devices are impeded by the intrinsic surface defects and environmental adsorption such as H2O and O2. Here, we demonstrated a highly ordered, ultrathin (<5 nm) and scalable N,N'-ditridecylperylene-3,4,9,10-tetracarboxylic diimide (PTCDI-C13) passivation layer that can be epitaxially grown on MoS2. The van der Waals interface between PTCDI-C13 and MoS2 can efficiently reduce the surface traps and isolate MoS2 from ambient. As a result, the passivated devices exhibit huge improvement in both carrier mobility (from 0.5 to 8.3 cm2/(V s)) and sub-threshold swing (from 16.7 to 1.6 V/dec). Also, the photodetector made on MoS2 after passivation has a much faster response speed (from 3 s to 10 ms) without significant sacrifice of the responsivity. Our method provides a facile approach to realize high-performance two-dimensional electronic and optoelectronic devices.

8.
J Nanosci Nanotechnol ; 18(6): 4176-4181, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29442759

RESUMEN

Pd-SnO2 composite nanoceramics have been prepared from SnO2 and Pd nanoparticles through traditional pressing and sintering. Their responses to CO at room temperature are found to depend greatly on the content of Pd. For those samples with 1.0 and 5.0 mol% Pd, their resistance increases dramatically upon being exposed to CO in air; while for samples of 0.2 mol% Pd, their resistance decreases greatly upon being exposed to CO in air, and extraordinary room-temperature CO sensing capabilities, including high sensitivities around 15, short response time of 20 s and recovery time of 60 s for 100 ppm CO in air, a high selectivity against H2, have been observed for them. X-ray photoelectron spectroscopy analyses showed that Pd2+ was formed in samples of 1 mol% Pd, while both Pd2+ and Pd4+ were formed in samples of 0.2 mol% Pd. It is proposed that for Pd-SnO2 composite nanoceramics, Pd2+ is responsible for CO-induced increase while Pd4+ is responsible for CO-induced decrease in resistance.

9.
Nanotechnology ; 27(41): 415202, 2016 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-27595326

RESUMEN

Graphene (G), TiO2 fusiform nanorods (TiO2NRs) adsorbed with Au nanoparticles (AuNPs) are prepared and blended as multifunctional materials into TiO2 nanocrystalline film to form a novel ternary (G-TiO2NRs-Au) composite photoanode in dye-sensitized solar cells (DSSCs). The effects of G-TiO2NRs-Au on the properties of the photoanode and DSSC are investigated. Results show that, by blending G-TiO2NRs-Au, the light absorption and scattering of the photoanode are obviously improved, and the charge transfer resistance R2 and electron recombination are decreased, resulting in a significant enhancement in the short-circuit current density (J sc) and the photoelectric conversion efficiency (PCE) of the DSSCs. The maximum J sc of 17.66 mA cm(-2) and PCE of 8.56% are obtained in the optimal G-TiO2NRs-Au-based DSSC, about 33.6% and 35.0% higher than that obtained in the conventional TiO2-based DSSC. This significant improvement in the performance of the DSSC can be attributed to the ternary composite complementary effects of multi-functions from the surface plasmon resonance of AuNPs, light scattering of TiO2NRs, and the improved dye loading and fast electron transmission channel from graphene. This study provides an effective way of ternary composite complementary enhancement of the J sc and PCE of the DSSCs.

10.
World J Gastroenterol ; 21(9): 2629-37, 2015 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-25759530

RESUMEN

AIM: To investigate GATA5, SFRP2, and ITGA4 methylation in plasma DNA as noninvasive biomarkers for colorectal cancer (CRC) or adenomas. METHODS: There were 57 CRC patients, 30 adenomas patients, and 47 control patients enrolled in this study. Methylation-specific polymerase chain reaction was used to determine the promoter methylation status of GATA5, SFRP2, and ITGA4 genes in plasma DNA, and their association with clinical outcome in CRC. The predictive ability of GATA5, SFRP2, and ITGA4 methylation, individually or in combination, to detect CRC or adenomas was further analyzed. RESULTS: Hypermethylated GATA5 was detected in plasma in 61.4% (35/57) of CRC cases, 43.33% (13/30) of adenoma cases, and 21.28% (10/47) of control cases. The hypermethylation of SFRP2 was detected in 54.39% (31/57), 40.00% (12/30), and 27.66% (13/47) in plasma samples from CRC, adenomas, and controls, respectively. ITGA4 methylation was detected in 36.84% (21/57) of plasma samples of CRC patients and in 30.00% (9/30) of plasma samples from patients with colorectal adenomas, and the specificity of this individual biomarker was 80.85% (9/47). Moreover, GATA5 methylation in the plasma was significantly correlated with larger tumor size (P = 0.019), differentiation status (P = 0.038), TNM stage (P = 0.008), and lymph node metastasis (P = 0.008). SFRP2 and ITGA4 methylation in plasma significantly correlated with differentiation status (SFRP2, P = 0.012; ITGA4, P = 0.007), TNM stage (SFRP2, P = 0.034; ITGA4, P = 0.021), and lymph node metastasis (SFRP2, P = 0.034; ITGA4, P = 0.021). From the perspective of predictive power and cost-performance, using GATA5 and SFRP2 together as methylation markers seemed the most favorable predictor for CRC (OR = 8.06; 95%CI: 2.54-25.5; P < 0.01) and adenomas (OR = 3.35; 95%CI: 1.29-8.71; P = 0.012). CONCLUSION: A combination of GATA5 and SFRP2 methylation could be promising as a marker for the detection and diagnosis of CRC and adenomas.


Asunto(s)
Adenoma/genética , Biomarcadores de Tumor/genética , Neoplasias Colorrectales/genética , Metilación de ADN , Factor de Transcripción GATA5/genética , Proteínas de la Membrana/genética , Adenoma/sangre , Adenoma/patología , Anciano , Biomarcadores de Tumor/sangre , Estudios de Casos y Controles , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/patología , Femenino , Factor de Transcripción GATA5/sangre , Humanos , Integrina alfa4/sangre , Integrina alfa4/genética , Metástasis Linfática , Masculino , Proteínas de la Membrana/sangre , Persona de Mediana Edad , Estadificación de Neoplasias , Oportunidad Relativa , Reacción en Cadena de la Polimerasa , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Carga Tumoral
11.
Oncol Lett ; 8(4): 1745-1750, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25202403

RESUMEN

Gastric cancer (GC) is one of the most frequently diagnosed malignancies in East Asia, particularly in China, and remains the second leading cause of cancer-associated mortality worldwide. However, no effective plasma biomarkers have been identified for the diagnosis of patients with GC. The aim of this study was to investigate the DNA methylation status of the ring finger protein 180 (RNF180), secreted frizzled-related protein 2 (SFRP2) and death-associated protein kinase 1 (DAPK1) genes in the plasma samples of 57 GC patients and 42 control individuals with no malignant disease, and to evaluate the clinical utility of these makers. A significantly higher level of methylation was observed in the plasma DNA of GC patients when compared with that of controls for the three genes investigated (RNF180, 57.89% vs. 23.81%; DAPK1, 49.12% vs. 28.57%; and SFRP2, 71.93% vs. 42.86%). No association was identified between the DAPK1 or SFRP2 methylation level in the plasma DNA and the clinicopathological parameters of patients. Notably, RNF180 methylation was found to positively correlate with tumor size (P=0.018), histological type (P=0.025), TNM stage (P=0.002), lymph node metastasis (P=0.008) and distant metastasis (P=0.018). Overall, 50 cancer patients (87.72%) exhibited methylation of at least one of the three markers, while 26 normal subjects presented methylation in plasma DNA [specificity, 38.1%; odds ratio (OR), 4.4]. The combined use of RNF180 and SFRP2 as methylation markers appeared to be the most preferable predictor with regard to predictive power and cost-performance (OR, 5.57; P=0.0002). The results of the present study indicate that aberrant promoter methylation of genes in the plasma may be detected in a substantial proportion of GC patients and thus, these genes must be evaluated in the screening and surveillance of GC.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(9): 2446-9, 2009 Sep.
Artículo en Chino | MEDLINE | ID: mdl-19950649

RESUMEN

The Raman spectroscopic analysis for eleven different rank coals (57.58% to 94.01% of Cdaf, %) indicated that two distinct bands, i.e., D band (1340-1380 cm(-1)) and G band (1580-1600 cm(-1)), exist in the first order of Raman spectra, with the former being broader and the latter rather sharp. As the two bands were overlapped each other, each spectrum was fitted with two Lorentz peaks and the Raman information about position, intensity and FWHM of each band was thus obtained. The relation of these Raman parameters with Cdaf% showed that with the increase in C%, the position of D band and G band shifts to lower and higher frequency, respectively; the separation of the two band positions increases with the increase in C%; FWHM-D, FWHM-G and I(D)/I(G) have linear relationship with Cdaf% in the range of Cdaf% 75%-94%. The coal structural parameters, d002 and Lc from XRD are related with the position and FWHM of G band; the comparison of La from XRD and both from the Cancado and the KW equation indicated that the values from Cancado and the KW equation are unreasonable.

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