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1.
Adv Sci (Weinh) ; : e2402645, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738739

RESUMEN

The photocatalytic reduction of CO2 represents an environmentally friendly and sustainable approach for generating valuable chemicals. In this study, a thiophene-modified highly conjugated asymmetric covalent triazine framework (As-CTF-S) is developed for this purpose. Significantly, single-component intramolecular energy transfer can enhance the photogenerated charge separation, leading to the efficient conversion of CO2 to CO during photocatalysis. As a result, without the need for additional photosensitizers or organic sacrificial agents, As-CTF-S demonstrates the highest photocatalytic ability of 353.2 µmol g-1 and achieves a selectivity of ≈99.95% within a 4 h period under visible light irradiation. This study provides molecular insights into the rational control of charge transfer pathways for high-efficiency CO2 photoreduction using single-component organic semiconductor catalysts.

2.
Inorg Chem ; 62(39): 15963-15970, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37725073

RESUMEN

Solar-driven high-efficiency conversion of CO2 with water vapor into high-value-added alcohols is a promising approach for reducing CO2 emissions and achieving carbon neutrality. However, the rapid recombination of photogenerated carriers and low CO2 adsorption capacity of photocatalysts are usually the factors that limit their applicability. Herein, a series of low-cost Z-scheme heterostructures Cu2O/PCN-250-x are constructed by in situ growth of ultrasmall Cu2O nanoparticles on PCN-250. A systematic investigation revealed that there is a strong interaction between Cu2O nanoparticles and PCN-250. The resulting Cu2O/PCN-250-2 exhibits excellent photogenerated carrier separation efficiency and CO2 adsorption capacity, which dramatically promote the conversion of CO2 into alcohols. Notably, the total yield of 268 µmol gcat-1 for the production of CH3OH and CH3H2OH is superior to that of isolated PCN-250 and Cu2O. This study provides a new perspective for the design of a Cu2O nanoparticle/metal-organic framework Z-scheme heterojunction for the reduction of CO2 to alcohols with water vapor.

3.
Int J Ophthalmol ; 14(9): 1441-1448, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34540623

RESUMEN

Thyroid-associated ophthalmopathy (TAO) is an autoimmune disease. Recent studies have found the aberrant epigenetics in TAO, including DNA methylation, non-coding RNAs, and histone modification. Many genes have an aberrant level of methylation in TAO. For example, higher levels are found in CD14, MBP, ANGLE1, LYAR and lower levels in DRD4 and BOLL. Non-coding RNAs are involved in the immune response (miR-146a, miR-155, miR-96, miR-183), fibrosis regulation (miR-146a, miR-21, miR-29), adipogenesis (miR-27) and are thought to play roles in TAO. MicroRNA is also related to the clinical activity score (miR-Let7d-5p) and may be a predictor of glucocorticoid therapy (miR-224-5p). The quantities of H4 in TAO are increased compared with euthyroid control subjects, and the role of histone modifications in Graves' disease may lead to better understanding of its role in TAO. More studies are needed to explain the role of epigenetics in TAO and provide potential therapeutic strategies.

4.
Ying Yong Sheng Tai Xue Bao ; 32(5): 1854-1862, 2021 May.
Artículo en Chino | MEDLINE | ID: mdl-34042382

RESUMEN

To understand the decomposition of cattle dung in Seriphidium-dominated desert, the changes of dung physical and chemical properties were determined by setting different stacking times (0, 7, 29, 48, 58 h) in May (spring) and September (autumn), respectively. Mesh cage with different openings (no mesh cage, opening up and down, opening up, totally enclosed) were set up to explore the effects of different ecological functional groups of dung beetles on decomposition. The results showed that species richness of dung beetles in spring was significantly higher than that in autumn, and that the abundance of dung beetles in autumn was significantly higher than that in spring. The losses of moisture, total carbon, total nitrogen and total phosphorus in dung were mainly concentrated during 0-29 h in spring, being decreased by 39.4%, 13.9%, 32.1% and 26.7% at 29 h, respectively. Neutral detergent fiber and acid detergent fiber of the dung stacked for 58 h decreased significantly by 8.0% and 16.0% respectively. In autumn, moisture, neutral detergent fiber and acid detergent fiber decreased most rapidly during 0-7 h, being decreased by 85.6%, 10.2% and 20.2% at 7 h, respectively. The concentrations of neutral detergent fiber and acid detergent fiber increased during 7-58 h by 20.0% and 13.7%, respectively. The decomposition of total carbon, total nitrogen and total phosphorus mainly concentrated during 0-29 h, being reduced by17.5%, 55.0% and 64.8%, respectively. The mesh cage with different openings effectively prevented the entering of dung beetles from the corresponding ecological functional groups. With the increases of functional groups of dung beetles, the decomposition rate accelerated, with cattle dung of no mesh cage being significantly higher than other treatments. The species richness and abundance of dung beetles and the stacking time of dung significantly affected the decomposition of cattle dung.


Asunto(s)
Escarabajos , Animales , Bovinos , China , Heces , Nitrógeno , Estaciones del Año
5.
J Clin Endocrinol Metab ; 106(8): e2866-e2886, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-33877318

RESUMEN

CONTEXT: The activation of orbital fibroblasts, the prime targets in thyroid eye disease (TED), is central to its underlying pathogenesis. OBJECTIVE: We aimed to investigate the mechanism of TED orbital fibroblast activation from the perspective of noncoding RNA regulation. METHODS: Immunofluorescence (IF) staining was applied to evaluate the fibrotic changes in target cells. Cell proliferation was evaluated by 5-ethoxy 2-deoxyuridine and colony-formation assays. Collagen I concentration was determined by enzyme-linked immunosorbent assay. Human microarray analysis was performed on 3 TED and 3 healthy control orbital tissue samples. RESULTS: Bioinformatics analysis showed that cell adhesion signaling factors were differentially expressed in TED tissues, including intercellular adhesion molecule (ICAM)-1, ICAM-4, vascular cell adhesion molecule, and CD44, which were all upregulated in diseased orbital tissues. Long noncoding RNA LPAL2 level was also upregulated in orbital tissues and positively correlated with ICAM-1 and ICAM-4 expression. Stimulation of the TED orbital fibroblasts by transforming growth factor-ß1 (TGF-ß1) significantly increased the expression of ICAM-1, ICAM-4, and LPAL2. Knockdown of LPAL2 in orbital fibroblasts inhibited TGF-ß1-induced increases in cell adhesion factor levels and orbital fibroblast activation. Microarray profiling was performed on TED and normal orbital tissues to identify differentially expressed microRNAs, and miR-1287-5p was remarkably reduced within diseased orbital samples. miR-1287-5p was directly bound to the epidermal growth factor receptor (EGFR) 3' untranslated region and LPAL2, and LPAL2 modulated EGFR/protein kinase B (AKT) signaling through targeting miR-1287-5p. CONCLUSION: The LPAL2/miR-1287-5p axis modulated TGF-ß1-induced increases in cell adhesion factor levels and TED orbital fibroblast activation through EGFR/AKT signaling.


Asunto(s)
Adhesión Celular/fisiología , Fibroblastos/metabolismo , Oftalmopatía de Graves/metabolismo , MicroARNs/metabolismo , Órbita/metabolismo , ARN Largo no Codificante/metabolismo , Adulto , Anciano , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Femenino , Fibroblastos/efectos de los fármacos , Oftalmopatía de Graves/genética , Humanos , Masculino , Persona de Mediana Edad , Órbita/efectos de los fármacos , ARN Largo no Codificante/genética , Transducción de Señal/fisiología , Factor de Crecimiento Transformador beta1/farmacología , Adulto Joven
6.
Acta Haematol ; 132(2): 200-10, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24662949

RESUMEN

BACKGROUND: Increased circulating endothelial microparticles (EMPs) have been shown to associate with endothelial dysfunction. We explored the effect of iron on EMP generation by human umbilical vein endothelial cells (HUVECs) and the potential protective effect of carvedilol. METHODS: FeCl 3 was added to HUVEC culture. Iron entry into cells was monitored using fluorescent microscopic imaging, while the quantity of EMPs that was released was determined by flow cytometry. The apoptosis of HUVECs was assessed by annexin V/propidium iodide assay and caspase-3 expression. Membrane bleb formation was visualized using electron microscopy. Intracellular production of reactive oxygen species (ROS) was also monitored. The effects of beta-blockers, carvedilol and propranolol on these processes were determined by co-incubation in a dose-dependent manner. Iron entry into HUVECs was not blocked by either beta-blocker. Iron induced the generation of EMPs, the formation of membrane blebs, the apoptosis of HUVECs and the production of ROS, each in a dose-dependent manner. Carvedilol, but not propranolol, ameliorated all of these processes. RESULTS: Our result indicates that iron induces EMP generation and apoptosis of endothelial cells in association with increased oxidative stress. CONCLUSION: The protective effects of carvedilol, via its antioxidant effect, may have therapeutic potential in patients with iron overload.


Asunto(s)
Antagonistas Adrenérgicos beta/farmacología , Apoptosis/efectos de los fármacos , Carbazoles/farmacología , Micropartículas Derivadas de Células/efectos de los fármacos , Cloruros/farmacología , Compuestos Férricos/farmacología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Propanolaminas/farmacología , Anexina A5/análisis , Carvedilol , Caspasa 3/análisis , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Citometría de Flujo , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/ultraestructura , Humanos , Quelantes del Hierro/farmacología , Sobrecarga de Hierro , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Estrés Oxidativo/efectos de los fármacos , Propranolol/farmacología , Especies Reactivas de Oxígeno/metabolismo
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