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1.
Nature ; 584(7821): 377-381, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32814890

RESUMEN

Interfaces in heterostructures have been a key point of interest in condensed-matter physics for decades owing to a plethora of distinctive phenomena-such as rectification1, the photovoltaic effect2, the quantum Hall effect3 and high-temperature superconductivity4-and their critical roles in present-day technical devices. However, the symmetry modulation at interfaces and the resultant effects have been largely overlooked. Here we show that a built-in electric field that originates from band bending at heterostructure interfaces induces polar symmetry therein that results in emergent functionalities, including piezoelectricity and pyroelectricity, even though the component materials are centrosymmetric. We study classic interfaces-namely, Schottky junctions-formed by noble metal and centrosymmetric semiconductors, including niobium-doped strontium titanium oxide crystals, niobium-doped titanium dioxide crystals, niobium-doped barium strontium titanium oxide ceramics, and silicon. The built-in electric field in the depletion region induces polar structures in the semiconductors and generates substantial piezoelectric and pyroelectric effects. In particular, the pyroelectric coefficient and figure of merit of the interface are over one order of magnitude larger than those of conventional bulk polar materials. Our study enriches the functionalities of heterostructure interfaces, offering a distinctive approach to realizing energy transduction beyond the conventional limitation imposed by intrinsic symmetry.

2.
Anal Bioanal Chem ; 416(17): 3859-3867, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38613684

RESUMEN

Electrochemiluminescence (ECL) is a luminescence production technique triggered by electrochemistry, which has emerged as a powerful analytical technique in bioanalysis and clinical diagnosis. During ECL, charge transfer (CT) is an important process between electrochemical excitation and luminescent emission, and dramatically affects the efficiency of exciton generation, playing a pivotal role in the light-emitting properties of nanomaterials. Reticular framework materials with intramolecular/intermolecular interactions offer a promising platform for regulating CT pathways and enhancing luminescence efficiency. Deciphering the role of intramolecular/intermolecular CT processes in reticular framework materials allows for the targeted design and synthesis of emitters with precisely controlled CT properties. This sheds light on the microscopic mechanisms of electro-optical conversion in ECL, propelling advancements in their efficiency and breakthrough applications. This mini-review focuses on recent advancements in engineering CT within reticular frameworks to boost ECL efficiency. We summarized strategies including intra-reticular charge transfer, CT between the metal and ligands, and CT between guest molecules and frameworks within reticular frameworks, which holds promise for developing next-generation ECL devices with enhanced sensitivity and light emission.

3.
Org Biomol Chem ; 22(1): 159-168, 2023 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-38051231

RESUMEN

Peroxynitrite (ONOO-) and glutathione (GSH) play mutually regulating roles in the oxidant-antioxidant balance of organisms, which has a profound relationship with people's health and disease. In this study, we designed a two-photon fluorescent probe CD-NA that could simultaneously detect ONOO- and GSH via dual-fluorophore and dual-site properties. CD-NA shows different fluorescence responses to ONOO- (annihilated red fluorescence) and GSH (enhanced green emission) with high specificity and sensitivity. Notably, the response of CD-NA to ONOO- was unaffected by GSH, and the reverse is also true. It allows the ONOO-/GSH cross-talk to be successfully imaged. Given these excellent properties, CD-NA has been favorably employed in detecting ONOO- and GSH in living cells with the ability to target mitochondria. Therefore, CD-NA offers an efficient method for understanding the oxidant-antioxidant balance and interrelated physiological functions of ONOO- and GSH in living systems, and provides a new strategy to sort out the complex relationships and roles of various analytes in complex physiological processes.


Asunto(s)
Antioxidantes , Colorantes Fluorescentes , Humanos , Ácido Peroxinitroso , Oxidantes , Glutatión
4.
J Nanobiotechnology ; 21(1): 362, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37794449

RESUMEN

PURPOSE: Endothelial cell dysfunction is a major cause of early atherosclerosis. Although the role of extracellular vesicles in stabilizing atherosclerotic plaques is well established, the effect of circulating exosomes on plaque formation is still unknown. Here, we explored the effect of exosomes on atherosclerosis based on the function that exosomes can act on intercellular communication. PATIENTS AND METHODS: We extracted serum exosomes from the blood of CHD patients (CHD-Exo) and healthy individuals (Con-Exo). The obtained exosomes were co-cultured with human umbilical vein endothelial cells (HUVECs) in vitro. In addition, we determined that circ_0001785 functions as a competing endogenous RNA (ceRNAs) in coronary artery disease by dual luciferase reporter gene analysis. The protective effect of circ_0001785 against endothelial cell injury was also verified using over-expression lentiviral transfection functional assays. In vivo experiments, we injected over-expressed circ_0001785 lentivirus into the tail vein of mice to observe its therapeutic effect on a mouse model of atherosclerosis. RESULTS: The vitro co-cultured results showed that the amount of plasma-derived exosomes have an increase in patients with coronary artery disease, and the inflammation and apoptosis of endothelial cells were exacerbated. Over-expression of circ_0001785 reduced endothelial cell injury through the ceRNA network pathway of miR-513a-5p/TGFBR3. Quantitative reverse transcription-polymerase chain reaction identified that the expressed amount of circ_0001785 was reduced in the circulating peripheral blood of CHD patients and increased within human and mouse atherosclerotic plaque tissue. The results of in vivo experiments showed that circ_0001785 reduced aortic endothelial cell injury and the formation of intraplaque neo-vascularization, and enhanced left ventricular diastolic function, thereby delaying the development of atherosclerosis in mice. CONCLUSION: Our results demonstrated a new biomarker, exosome-derived circ_0001785, for atherogenesis, which can reduce endothelial cell injury and thus delay atherogenesis through the miR-513a-5p/TGFBR3 ceRNA network mechanism, providing an exosome-based intervention strategy for atherosclerosis.


Asunto(s)
Aterosclerosis , Enfermedad de la Arteria Coronaria , Exosomas , MicroARNs , Placa Aterosclerótica , Humanos , Animales , Ratones , Aterosclerosis/genética , Células Endoteliales de la Vena Umbilical Humana , MicroARNs/genética , Proliferación Celular
5.
Molecules ; 28(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36903566

RESUMEN

A batch of Fe-modified biochars MS (for soybean straw), MR (for rape straw), and MP (for peanut shell) were prepared by impregnating biochars pyrolyzed from three different raw biomass materials, i.e., peanut shell, soybean straw, and rape straw, with FeCl3 solution in different Fe/C impregnation ratios (0, 0.112, 0.224, 0.448, 0.560, 0.672, and 0.896) in this research. Their characteristics (pH, porosities, surface morphologies, crystal structures, and interfacial chemical behaviors) and phosphate adsorption capacities and mechanisms were evaluated. The optimization of their phosphate removal efficiency (Y%) was analyzed using the response surface method. Our results indicated that MR, MP, and MS showed their best phosphate adsorption capacity at Fe/C ratios of 0.672, 0.672, and 0.560, respectively. Rapid phosphate removal was observed within the first few minutes and the equilibrium was attained by 12 h in all treatment. The optimal conditions for phosphorus removal were pH = 7.0, initial phosphate concentration = 132.64 mg L-1, and ambient temperature = 25 °C, where the Y% values were 97.76, 90.23, and 86.23% of MS, MP, and MR, respectively. Among the three biochars, the maximum phosphate removal efficiency determined was 97.80%. The phosphate adsorption process of three modified biochars followed a pseudo-second-order adsorption kinetic model, indicating monolayer adsorption based on electrostatic adsorption or ion exchange. Thus, this study clarified the mechanism of phosphate adsorption by three Fe-modified biochar composites, which present as low-cost soil conditioners for rapid and sustainable phosphate removal.


Asunto(s)
Fosfatos , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico/química , Fósforo , Contaminantes Químicos del Agua/química
6.
Molecules ; 28(24)2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38138644

RESUMEN

Two isostructural lanthanide complexes were synthesized by solvent evaporation with 3-dimethylaminobenzoic acid and 5,5'-dimethyl-2,2'-bipyridine as ligands. The general formula of the structure is a [Ln(3-N,N-DMBA)3(5,5'-DM-2,2'-bipy)]2·2(3-N,N-DMHBA), Ln = (Gd(1), Tb(2)), 3-N,N-DMBA = 3-Dimethylamino benzoate, 5,5'-DM-2,2'-bipy = 5,5'-dimethyl-2,2' bipyridine. Both complexes exhibited dimeric structures based on X-ray diffraction analysis. At the same time, infrared spectroscopy and Raman spectroscopy were used to measure the spectra of the complex. A thermogravimetric infrared spectroscopy experiment was performed to investigate the thermal stability and decomposition mechanism of the complexes. Measurements of the low-temperature heat capacity of the complexes were obtained within the temperature range of 1.9 to 300 K. The thermodynamic function was calculated by heat capacity fitting. In addition, the fluorescence spectra of complex 2 were studied and the fluorescence lifetime values were determined, and the energy transfer mechanism of complex 2 was elucidated.

7.
BMC Genomics ; 23(1): 698, 2022 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-36209069

RESUMEN

BACKGROUND: The dried stem of Cistanche, is a famous Chinese traditional medicine. The main active pharmacodynamic components are phenylethanol glycosides (PhGs). Cistanche tubulosa produces higher level of PhGs in its stems than that of Cistanche deserticola. However, the key genes in the PhGs biosynthesis pathway is not clear in C. tubulosa. RESULTS: In this study, we performed the full-length transcriptome sequencing and gene expression profiling of C. tubulosa using PacBio combined with BGISEQ-500 RNA-seq technology. Totally, 237,772 unique transcripts were obtained, ranging from 199 bp to 31,857 bp. Among the unique transcripts, 188,135 (79.12%) transcripts were annotated. Interestingly, 1080 transcripts were annotated as 22 enzymes related to PhGs biosynthesis. We measured the content of echinacoside, acteoside and total PhGs at two development stages, and found that the content of PhGs was 46.74% of dry matter in young fleshy stem (YS1) and then decreased to 31.22% at the harvest stage (HS2). To compare with YS1, 13,631 genes were up-regulated, and 15,521 genes were down regulated in HS2. Many differentially expressed genes (DEGs) were identified to be involved in phenylpropanoid biosynthesis pathway, phenylalanine metabolism pathway, and tyrosine metabolism pathway. CONCLUSIONS: This is the first report of transcriptome study of C. tubulosa which provided the foundation for understanding of PhGs biosynthesis. Based on these results, we proposed a potential model for PhGs biosynthesis in C. tubulosa.


Asunto(s)
Cistanche , Alcohol Feniletílico , Cistanche/genética , Cistanche/metabolismo , Perfilación de la Expresión Génica , Glicósidos , Fenilalanina/metabolismo , Alcohol Feniletílico/metabolismo , Tirosina/metabolismo
8.
Lupus ; 31(8): 985-997, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35588147

RESUMEN

PURPOSE: Ferroptosis, characterized by iron accumulation and lipid peroxidation, is a newly demonstrated form of programed cell death. Present studies reveal that ferroptosis is involved in tumor and neurodegenerative disease. Regarding its roles in the development of LN, it is least interrogated. In this study, we explored whether ferroptosis is activated and how does it change at transcriptomic level in LN. METHODS: 4-Hydroxynonenal (4-HNE) was stained to explore whether ferroptosis is activated. Subsequently, by using bioinformatic methods, public GSE32591 dataset was analyzed. Ferroptosis-related differentially expressed genes (FR-DEGs) were identified in both glomeruli and tubulointerstitium. Immune cell infiltration was evaluated. Correlation between FR-DEGs and infiltrated immune cells was also calculated. Finally, dataset of GSE113342, qPCR, and immunofluorescence staining were also used or performed to validate the results. RESULTS: Expression of 4-HNE was significantly increased in both glomeruli and tubulointerstitium. At transcriptomic level, 19 FR-DEGs in glomeruli and 15 FR-DEGs in tubulointerstitium including genes of iron metabolism, antioxidant system inhibitors, and ferroptosis suppressors were significantly altered in LN. Of which, LTF, CYBB, and CCL5 were upregulated and G0S2 and AKR1C1 were downregulated in both glomeruli and tubulointerstitium of LN. qPCR further validated the alteration of LTF, CYBB, CCL5, G0S2, and AKR1C1 in the whole kidney. Correlation analysis showed that CYBB positively correlated with monocyte infiltration in glomeruli and positively correlated with response to therapy. CONCLUSION: Lipid peroxidation was aberrantly activated in LN, suggesting the activation of ferroptosis. LTF, CYBB, CCL5, G0S2, and AKR1C1, especially CYBB, might be good biomarkers of ferroptosis in LN.


Asunto(s)
Ferroptosis , Lupus Eritematoso Sistémico , Nefritis Lúpica , Enfermedades Neurodegenerativas , Biomarcadores , Ferroptosis/genética , Humanos , Hierro , Nefritis Lúpica/patología
9.
Ecotoxicol Environ Saf ; 226: 112817, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34563888

RESUMEN

Changes in the types and contents of metabolites in plants can occur in response to environmental stress. In this study, pumpkin seeds were cultivated in a cadmium ion solution (cadmium sulfate) for 7 days, and growth parameters, antioxidant enzyme activities, and metabolites in the root, stem, and leaf were analyzed. The results showed that cadmium accumulation characteristics were in the order of root > stem > leaf. Cadmium restrained root growth and promoted superoxide dismutase, peroxidase, catalase activities in the root, but inhibited their activities in the leaf. Cadmium did not change the total biomass of pumpkin seedlings. Orthogonal partial least squares (OPLS) analyses were conducted to detect the relationships between fresh weight and metabolites. These analyses revealed that maltose had significantly positive relationships with the fresh weight of the root, stem, and leaf. Cadmium influenced glyoxylate and dicarboxylate metabolism, aminoacyl-tRNA biosynthesis, sulfur metabolism, butanoate metabolism, alanine, aspartate and glutamate metabolism, glutathione metabolism, glycine, serine and threonine metabolism in the root; glycolysis/gluconeogenesis in the stem; and biosynthesis of unsaturated fatty acids, galactose metabolism, cutin, suberine and wax biosynthesis in the leaf. It is important that cadmium inhibited root growth by inhibiting carbohydrate transport from the leaf to the root and promoted leaf growth by the accumulation of carbohydrates in the leaf. Furthermore, cadmium also restrained amino acid metabolism in the root of pumpkin seedlings. These results provide new information about how pumpkin seedlings respond to cadmium stress.


Asunto(s)
Cucurbita , Plantones , Antioxidantes , Cadmio/toxicidad , Raíces de Plantas , Superóxido Dismutasa
10.
Ecotoxicol Environ Saf ; 212: 111998, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33540339

RESUMEN

Metabolomics is an implement for testing the toxicity of antibiotics, and provides a comprehensive view of the overall response to stress; however, the connections between metabolites and biologic endpoints keep unclear in response to antibiotics. In this study, wheat seeds were exposed to tetracycline for 5 days. The results proved that tetracycline restrained growth, reduced chlorophyl and carotinoid contents and cell permeability, and increased reactive oxygen species (ROS) levels and malondialdehyde (MDA) content. Orthogonal partial least squares (OPLS) was used to analyze the connections between metabolites and biologic endpoints, which discovered that 11 metabolic pathways were significantly affected by tetracycline, and amino acid metabolism could largely apply to root growth and ROS accumulation, while carbohydrate metabolism could have a ruling effect on tetracycline-induced cell permeability. 13 metabolites all played active roles in mediating tetracycline's effects on root length, root fresh weight and cell permeability but had no significant effects on ROS levels. The majority of metabolites with passive effects on root length, root fresh weight and cell permeability had active effects on ROS levels. These results offer a view about stress reaction of wheat to tetracycline.


Asunto(s)
Antibacterianos/toxicidad , Redes y Vías Metabólicas/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Tetraciclina/toxicidad , Triticum/efectos de los fármacos , Análisis de los Mínimos Cuadrados , Malondialdehído/metabolismo , Metabolómica/métodos , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Triticum/crecimiento & desarrollo , Triticum/metabolismo
11.
Pharmazie ; 76(4): 172-174, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33849703

RESUMEN

Triple-negative breast cancer (TNBC) is the most aggressive type of breast cancers. Chemotherapy is the most important therapeutic option for TNBC, and chemotherapy-induced nausea and vomiting (CINV) is inevitable. Metoclopramide is a good and cost-effective therapeutic option for chemotherapy-induced nausea and vomiting. However, it is not commonly used in breast cancer because it can increase serum prolactin levels by blocking dopamine D2 receptor. This study aimed at elucidating the effect of metoclopramide on triple-negative breast cancer, MDA-MB-231 cells were treated with various concentrations of metoclopramide, the cell proliferation was detected by MTT method, the apoptosis rate was detected by Annexin V/PI double staining method, the expression change of death-related protein was detected by Western Blot. We found that metoclopramide inhibits cell proliferation and induces cell apoptosis of MDA-MB-231 in a concentration-dependent manner, and the Bcl family was involved in this process.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Metoclopramida/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Antineoplásicos/administración & dosificación , Línea Celular Tumoral , Antagonistas de los Receptores de Dopamina D2/administración & dosificación , Antagonistas de los Receptores de Dopamina D2/farmacología , Relación Dosis-Respuesta a Droga , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Metoclopramida/administración & dosificación , Neoplasias de la Mama Triple Negativas/patología
12.
Small ; 16(42): e2004136, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32970394

RESUMEN

High-quality crystalline micro- and nanostructures based on inorganic semiconductors including zinc oxide (ZnO) have attracted considerable interest in electronic and optoelectronic applications due to their outstanding properties. ZnO micro- and nanocrystals can be fabricated by the moderate and high throughput hydrothermal synthesis. Yet it is restricted by patterning large-area ZnO crystals with high-quality and programmable geometries through the hydrothermal process for the optoelectronic integration. Here, a capillary-bridge manipulation approach is demonstrated to control the dewetting process of ZnO precursor solution for patterning precursor arrays. Based on precursor arrays, vertically aligned high-quality ZnO microrod arrays with homogeneous morphology and pure crystallographic orientation are fabricated via a hydrothermal epitaxial method. Statistical results and crystallization theories guide the experimental optimization and discussion of the crystallization mechanism, dominated by the competition between homogeneous nucleation and heterogeneous nucleation. High-quality ZnO microbelt arrays are achieved through a surfactant-mediated hydrothermal method after ZnO microrod arrays are transferred to a polydimethylsiloxane substrate. Photodetectors based on ZnO microbelts exhibit a high responsivity of 2.3 × 104 A W-1 , a light on-off ratio exceeding 105 , and stable recyclability. It is anticipated that this work provides new insights into patterning inorganic high-quality micro- and nanostructures for multi-functional integrated devices.

13.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(5): 536-541, 2020 May 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-32879103

RESUMEN

OBJECTIVES: Since the outbreak of coronavirus disease 2019 (COVID-19), it has spread rapidly in China and many other countries. The rapid increase in the number of cases has caused widespread panic among people and has become the main public health problem in the world. Severe patients often have difficult breathing and/or hypoxemia after 1 week of onset. A few critically ill patients may not only rapidly develop into acute respiratory distress syndrome, but also may cause coagulopathy, as well as multiple organs failure (such as heart, liver and kidney) or even death. This article is to analyze the predictive role of clinical features in patients with COVID-19 for severe disease, so as to help doctor monitor the severity-related features, restrain the disease progress, and provide a reference for improvement of medical treatment. METHODS: The clinical data of 208 patients with COVID-19 who were isolated and treated in Changsha Public Health Treatment Center from January 17, 2020 to March 14, 2020 were collected. All patients were the mild and ordinary adult patients on admission, including 105 males and 103 females from 19 to 84 (median age 44) years old. According to the "Program for the diagnosis and treatment of novel coronavirus (COVID-19) infected pneumonia (Trial version 7)" issued by the General Office of National Health Committee and Office of State Administration of Traditional Chinese Medicine as the diagnostic and typing criteria. According to progression from mild to severe disease during hospitalization, the patients were divided into a mild group (n=183) and a severe transformation group (n=25). The clinical features such as age, underlying disease, blood routine, coagulation function, blood biochemistry, oxygenation index, and so on were analyzed. Among them, laboratory tests included white blood cell (WBC), lymphocytes (LYM), neutrophil (NEU), hemoglobin (Hb), platelet (PLT), prothrombin time (PT), plasma fibrinogen (Fib), activated partial prothrombin time (APTT), thrombin time (TT), D-dimer, total bilirubin (TBIL), albumin (ALB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), serum creatinine (Cr), creatine kinase (CK), creatine kinase isoenzyme-MB (CK-MB), lactate dehydrogenase (LDH), C-reactive protein (CRP), and oxygen partial pressure in arterial blood. Partial pressure of oxygen in arterial blood/fractional concentration of inspiratory oxygen (PaO2/FiO2) was calculated. The variables with statistical significance were analyzed by logistic regression analysis. RESULTS: Patients in the severe transformation group had more combined underlying diseases than those in the mild group (P<0.05). From the perspective of disease distribution, patients in the severe transformation group had more combined hypertension (P<0.05). In the severe transformation group, PT was significantly longer, the levels of Fib, ALT, AST, CK, LDH, and CRP were significantly higher than those in the mild group (P<0.05 or P<0.001), while LYM, ALB, and PaO2/FiO2 were significantly lower than those in the mild group (P<0.05 or P<0.001). Logistic regression analysis was performed on clinical features with statistically significant differences. Combined with hypertension, LYM, PT, Fib, ALB, ALT, AST, CK, LDH, and CRP as independent variables, and having severe disease or not was the dependent variable. The results show that combined hypertension, decreased LYM, longer PT, and increased CK level were independent risk factors that affected the severity of COVID-19 (P<0.05). CONCLUSIONS: The patients with mild COVID-19 who are apt to develop severe diseases may be related to combined hypertension, decreased LYM, and longer PT, and increased CK level. For the mild patients with these clinical features, early intervention may effectively prevent the progression to severe diseases.


Asunto(s)
Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Betacoronavirus , COVID-19 , China , Infecciones por Coronavirus/fisiopatología , Progresión de la Enfermedad , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/fisiopatología , Estudios Retrospectivos , SARS-CoV-2 , Adulto Joven
14.
Bioconjug Chem ; 29(3): 786-794, 2018 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-29382195

RESUMEN

A simple and effective strategy was developed to enrich ubiquitinated proteins (UPs) from cancer cell lysate using the α-Al2O3 nanoparticles covalently linked with ubiquitin binding protein (Vx3) (denoted as α-Al2O3-Vx3) via a chemical linker. The functionalized α-Al2O3-Vx3 showed long-term stability and high efficiency for the enrichment of UPs from cancer cell lysates. Flow cytometry analysis results indicated dendritic cells (DCs) could more effectively phagocytize the covalently linked α-Al2O3-Vx3-UPs than the physical mixture of α-Al2O3 and Vx3-UPs (α-Al2O3/Vx3-UPs). Laser confocal microscopy images revealed that α-Al2O3-Vx3-UPs localized within the autophagosome of DCs, which then cross-presented α-Al2O3-Vx3-UPs to CD8+ T cells in an autophagosome-related cross-presentation pathway. Furthermore, α-Al2O3-Vx3-UPs enhanced more potent antitumor immune response and antitumor efficacy than α-Al2O3/cell lysate or α-Al2O3/Vx3-UPs. This work highlights the potential of using the Vx3 covalently linked α-Al2O3 as a simple and effective platform to enrich UPs from cancer cells for the development of highly efficient therapeutic cancer vaccines.


Asunto(s)
Óxido de Aluminio/uso terapéutico , Nanopartículas/uso terapéutico , Neoplasias/prevención & control , Proteínas Ubiquitinadas/uso terapéutico , Óxido de Aluminio/química , Óxido de Aluminio/inmunología , Animales , Autofagosomas/inmunología , Línea Celular Tumoral , Células Dendríticas/citología , Células Dendríticas/inmunología , Femenino , Proteínas Inmovilizadas/química , Proteínas Inmovilizadas/inmunología , Proteínas Inmovilizadas/uso terapéutico , Ratones Endogámicos BALB C , Nanopartículas/química , Neoplasias/inmunología , Fagocitosis , Proteínas Ubiquitinadas/química , Proteínas Ubiquitinadas/inmunología
15.
Plasmid ; 98: 52-55, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-30201136

RESUMEN

RNA interference (RNAi), based on hairpin RNA (hpRNA) expression, plays an important role in functional analysis of plant genes. Traditional methods for making RNAi constructs usually involve multiple time-consuming cloning steps. We have developed a Gateway-compatible binary vector for RNAi-mediated gene knockdown in plants from pCAMBIA2301 and pHANNIBAL vectors. The new plant RNAi binary vector, named pCAMBIA2301-GW-RNAi, has two inverted repeated Gateway cassettes driven by the cauliflower mosaic virus 35S (CaMV 35S) promoter. This enables site-specific recombination at two sites by one Gateway LR reaction without restriction enzymes and ligases. The pCAMBIA2301-GW-RNAi vector's effectiveness was evaluated by Agrobacterium-mediated transient co-expression assays of overexpression and silencing constructs of HvCEBiP in Nicotiana benthamiana followed by western blot analysis. Obtained results show that the developed RNAi vector successfully knocked down 35S-driven expression of HvCEBiP, as expression levels of the encoded HvCEBiP protein were significantly reduced.


Asunto(s)
Agrobacterium/genética , Técnicas de Silenciamiento del Gen/métodos , Genes de Plantas , Vectores Genéticos , Nicotiana/genética , Plásmidos/genética , Interferencia de ARN , Nicotiana/microbiología
16.
Bioconjug Chem ; 28(4): 1166-1175, 2017 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-28191958

RESUMEN

d-Amino acid oxidases (DAAOs) are flavor enzymes and have been used in resolution of racemic amino acids and manufacturing of pharmaceuticals. However, the evolved H2O2 during the catalysis has deleterious and inhibitory effects. Decomposition of the hydrogen peroxide by catalase (CAT) can eliminate the negative effects. DAAO and CAT are dimeric and tetrameric proteins, respectively. Here, the N-terminus of the DAAO subunits has been specifically ligated to the C-terminus of the CAT subunits with native peptides through intein-mediated in vivo protein splicing. The in vivo splicing has little effect on the secondary structures of the enzymes as confirmed by circular dichroism (CD) spectra, and fluorescence spectra showed that the spliced product DAAO&CAT has a higher stability than DAAO. In the spliced product DAAO&CAT, the DAAO subunits are in close proximity to the CAT subunits, facilitating immediate transfer of H2O2 from one catalytic site to the other, enabling efficient decomposition of the generated H2O2. The reduced cofactors of the DAAO subunits were reoxidized by the evolved molecular oxygen around. Kinetics analysis showed that the d-alanine substrate follows Michaelis-Menten kinetics. The catalytic efficiency of DAAO&CAT is 22.4-fold that of DAAO. Furthermore, the spliced product DAAO&CAT has been encapsulated within a coordination polymer with an encapsulation efficiency of 91.3 ± 2.7%. The encapsulated DAAO&CAT has retained 98.1 ± 3.1% and 94.9 ± 2.9% of the activity of free DAAO&CAT at 30 and 40 °C, respectively.


Asunto(s)
Aminoácido Oxidorreductasas/química , Catalasa/química , Péptidos/química , Aminoácido Oxidorreductasas/metabolismo , Catalasa/metabolismo , Peróxido de Hidrógeno/síntesis química , Peróxido de Hidrógeno/metabolismo , Cinética , Empalme de Proteína , Subunidades de Proteína
17.
Virol J ; 12: 192, 2015 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-26577955

RESUMEN

BACKGROUND: HBV X protein (HBX) is associated with cell apoptosis mediated by TNF-α related apoptosis inducing ligand (TRAIL), while the role of HBX on the expressions of TRAIL receptors death receptor 4 (DR4) and DR5 are unclear. In this study, we detected the cell apoptosis induced by TRAIL as well as gene and protein expressions of DR4 and DR5 in Huh-7 cells steadily transfected with HBX (Huh-7-HBX cells). In addition, we investigated the activation of different pathways associated with the expressions of TRAIL receptors in Huh-7-HBX cells. METHODS: The apoptosis of Huh-7-HBX cells induced by TRAIL was evaluated by flow cytometry analysis. The levels of DR4 and DR5 expression in cells were determined by real-time PCR and western blotting analysis. The activities of JNK pathway and NF-kappaB (NF-κB) pathway were demonstrated by western blotting assay. RESULTS: Compared to control cells, the percentage of cell apoptosis was increased in Huh-7-HBX cells. The increased expressions of DR4 and DR5 on gene and protein levels were observed in Huh-7-HBX cells. Further researches suggested that activation of JNK pathway was increased but not involved in the expression of TRAIL receptors in HBX positive cells. The activation of NF-κB pathway increased and was responsible for DR5 expression and cell apoptosis in HBX positive cells. CONCLUSIONS: These results demonstrate that increased apoptosis induced by TRAIL is associated with increased expression of DR5 that mediated by HBX through NF-κB pathway. This finding provides a critical insight into the mechanism of hepatocyte apoptosis mediated by HBX in HBV infection.


Asunto(s)
Apoptosis , Virus de la Hepatitis B/fisiología , Hepatocitos/virología , FN-kappa B/metabolismo , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/biosíntesis , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Transactivadores/metabolismo , Western Blotting , Línea Celular , Citometría de Flujo , Hepatocitos/fisiología , Interacciones Huésped-Patógeno , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Reguladoras y Accesorias Virales
18.
J Immunother ; 47(2): 33-48, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37982646

RESUMEN

Tumor-associated macrophages (TAMs) are highly infiltrated in the tumor microenvironment (TME) of colorectal cancer (CRC) and play a vital role in CRC's development as well as prognosis. The required data were obtained from the Gene Expression Omnibus database and The Cancer Genome Atlas. Univariate Cox regression and least absolute shrinkage operator analyses were executed for model construction. TME assessment and immune prediction were performed using the ESTIMATE software package and the single sample genome enrichment analysis algorithm. The results show patients with low a TAMs risk score (TRS) had a better prognosis in both The Cancer Genome Atlas and Gene Expression Omnibus cohorts. Patients with low TRS were more sensitive to 3 chemotherapeutic agents: oxaliplatin, paclitaxel, and cisplatin ( P <0.05). TME assessment showed that the low TRS group had less infiltration of M2 macrophages and regulatory T cells, but CD4 + T cells, NK cells, and dendritic cells occupy a greater proportion of TME. Low TRS group patients have a low StromalScore and ImmuneScore but have high TumorPurity. The immune checkpoint TIM-3 gene HAVCR2 expression was significantly higher in the high TRS group. Finally, we created a nomogram including TRS for forecasting survival, and TRS was significantly associated with the clinical stage of the patients. In conclusion, the TRS serves as a reliable prognostic indicator of CRC; it predicts patient outcomes to immunotherapy and chemotherapy and provides genomic evidence for the subsequent development of modulated TAMs for treating CRC.


Asunto(s)
Macrófagos , Neoplasias , Humanos , Resultado del Tratamiento , Macrófagos Asociados a Tumores , Linfocitos T CD4-Positivos , Microambiente Tumoral , Pronóstico
19.
Chemistry ; 19(30): 10017-23, 2013 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-23775816

RESUMEN

Dual-mesoporous ZSM-5 zeolite with highly b axis oriented large mesopores was synthesized by using nonionic copolymer F127 and cationic surfactant CTAB as co-templates. The product contains two types of mesopores--smaller wormlike ones of 3.3 nm in size and highly oriented larger ones of 30-50 nm in diameter along the b axis--and both of them interpenetrate throughout the zeolite crystals and interconnect with zeolite microporosity. The dual-mesoporous zeolite exhibits excellent catalytic performance in the condensation of benzaldehyde with ethanol and greater than 99 % selectivity for benzoin ethyl ether at room temperature, which can be ascribed to the zeolite lattice structure offering catalytically active sites and the hierarchical and oriented mesoporous structure providing fast access of reactants to these sites in the catalytic reaction. The excellent recyclability and high catalytic stability of the catalyst suggest prospective applications of such unique mesoporous zeolites in the chemical industry.

20.
Cell Signal ; 112: 110928, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37844714

RESUMEN

Heat shock proteins (HSP) are a large family of peptide proteins that are widely found in cells. Studies have shown that the expression and function of HSPs in cells are very complex, and they can participate in cellular physiological and pathological processes through multiple pathways. Multiple heat shock proteins are associated with cancer cell growth, proliferation, metastasis, and resistance to anticancer drugs, and they play a key role in cancer development by ensuring the correct folding or degradation of proteins in cancer cells. As research hotspots, HSP90, HSP70 and HSP27 have been extensively studied in cancer so far. However, HSP20, also referred to as HSPB6, as a member of the small heat shock protein family, has been shown to play an important role in the cardiovascular system, but little research has been conducted on HSP20 in cancer. This review summarizes the current cellular functions of HSP20 in different cancer types, as well as its effects on cancer proliferation, progression, prognosis, and its other functions in cancer, to illustrate the close association between HSP20 and cancer. We show that, unlike most HSPs, HSP20 mainly plays an active anticancer role in cancer development, which is expected to provide new ideas and help for cancer diagnosis and treatment and research.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Proteínas de Choque Térmico/metabolismo , Neoplasias/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas del Choque Térmico HSP20/metabolismo
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