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The mitigation of environmental and energy crises could be advanced by reclaiming platinum group precious metals (PGMs) from decommissioned air purification catalysts. However, the complexity of catalyst composition and the high chemical inertness of PGMs significantly impede this process. Consequently, recovering PGMs from used industrial catalysts is crucial and challenging. This study delves into an environmentally friendly approach to selectively recover PGMs from commercial air purifiers using photocatalytic redox technology. Our investigation focuses on devising a comprehensive strategy for treating three-way catalysts employed in automotive exhaust treatment. By meticulously pretreating and modifying reaction conditions, we achieved noteworthy results, completely dissolving and separating rhodium (Rh), palladium (Pd), and platinum (Pt) within a 12-h time frame. Importantly, the solubility selectivity persists despite the remarkably similar physicochemical properties of Rh, Pd, and Pt. To bolster the environmental sustainability of our method, we harness sunlight as the energy source to activate the photocatalysts, facilitating the complete dissolution of precious metals under natural light irradiation. This eco-friendly recovery approach demonstrated on commercial air purifiers, exhibits promise for broader application to a diverse range of deactivated air purification catalysts, potentially enabling implementation on a large scale.
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OBJECTIVES: Amyloid ß-protein (Aß)-induced apoptosis and oxidative stress of human brain microvascular endothelial cells(BMECs) are contributors to the development of Alzheimer's disease (AD). Acteoside has shown its therapeutic potential for AD treatment. Therefore, this study investigated the effect of acteoside on Aß-induced blood-brain barrier damage, oxidative stress and apoptosis as well as to explore the underlying mechanisms through network pharmacology. METHODS: The study used Aß to induce human BMECs to construct an in-vitro injury model. Following treatment with acteoside, transendothelial electrical resistance (TEER), RT-qPCR and Western blot were used to evaluate the permeability of BMECs. The apoptosis level was detected by TUNEL and Western blot, ROS assay kit was used for the detection of reactive oxygen species (ROS) expression. The let-7g-5p expression level was detected by RT-qPCR. After additional treatment with let-7g-5p inhibitor, corresponding assays were performed again. Finally, network pharmacology was used to verify the mechanism. RESULTS: Acteoside decreased the permeability, oxidative stress and cell apoptosis of Aß-stimulated cells. More importantly, acteoside-activated let-7g-5p and additional treatment with let-7g-5p inhibitor abated the effects of acteoside on Aß-induced permeability, oxidative stress and apoptosis of Aß-stimulated BMECs. According to network pharmacology, 233 targeted genes of acteoside and 122 potential targets of let-7g-5p were determined by screening several databases, and two targets called Casp-3 and ITGB3 were obtained after taking the intersection. CONCLUSION: In conclusion, these results reveal that acteoside-activated let-7g-5p attenuating Aß-induced increased permeability and apoptosis of human BMECs.
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Doença de Alzheimer , MicroRNAs , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/farmacologia , Apoptose , Encéfalo/metabolismo , Células Endoteliais/metabolismo , Glucosídeos , Humanos , MicroRNAs/metabolismo , Farmacologia em Rede , Permeabilidade , Polifenóis , Espécies Reativas de Oxigênio/metabolismoRESUMO
OBJECTIVE: The proteoglycan versican (VCAN) plays an important role in extracellular matrix (ECM) assembly, and diminished maintenance of the ECM has been increasingly regarded as an important factor in the development of intracranial aneurysms (IAs). Previous studies have revealed that single-nucleotide polymorphisms (SNPs) of the VCAN gene are associated with susceptibility to IAs in European or Japanese populations. However, the association between IA susceptibility and VCAN SNPs in the Eastern Chinese population remains unclear. This study aimed to investigate the associations of the SNPs rs251124, rs2287926, and rs173686 with IA susceptibility in the Eastern Chinese population. METHODS: A total of 162 patients with IA and 182 controls were enrolled in this study. The study was conducted between January 2017 and December 2020. SNP genotyping for rs251124, rs2287926, and rs173686 was performed using Kompetitive Allele Specific PCR (KASP) after DNA extraction. The SNP data were analysed with CFX Manager Software version 3.1 (Bio-Rad). RESULTS: rs251124 and rs173686 were significantly associated with susceptibility to IA. The frequency of rs251124-TT in IA was higher than in controls (OR =1.26, 95% CI: 1.07-1.49; P<0.01), and its risk mainly came from the T allele. Furthermore, logistic regression analysis showed that the T/T genotype and T allele of rs251124 were independent risk factors for IA (OR=1.726, 95% CI: 1.136-2.263; P=0.011). Moreover, the G/G genotype and G allele of rs173686 were associated with increased IA susceptibility (OR=2.52, 95% CI: 1.261-5.037; P=0.009). CONCLUSION: The SNPs rs251124 and rs173686 were strongly associated with genetic susceptibility to IA in the Eastern Chinese population; however, no such association was found in the SNP rs2287926 of VCAN. Our findings suggest that the VCAN gene is an IA susceptible gene that should be further studied as a screening marker for IAs.
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The design of highly efficient and stable photocatalysts to utilize solar energy is a significant challenge in photocatalysis. In this work, a series of novel p-n heterojunction photocatalysts, Li2SnO3/g-C3N4, was successfully prepared via a facile calcining method, and exhibited superior photocatalytic activity toward the photodegradation of Rhodamine B solution under visible light irradiation as compared with pure Li2SnO3 and g-C3N4. The maximum kinetic rate constant of photocatalytic degradation of Rhodamine B within 60 min was 0.0302 min-1, and the composites still retained excellent performance after four successive recycles. Chemical reactive species trapping experiments and electron paramagnetic resonance demonstrated that hydroxyl radicals (·OH) and superoxide ions ( · O 2 - ) were the dominant active species in the photocatalytic oxidation of Rhodamine B solution, while holes (h+) only played a minor role. We demonstrated that the enhancement of the photocatalytic activity could be assigned to the formation of a p-n junction photocatalytic system, which benefitted the efficient separation of photogenerated carriers. This study provides a visible light-responsive heterojunction photocatalyst with potential applications in environmental remediation.
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Density functional theory (DFT) calculations have been performed to investigate the mechanism of alkaline-earth-metal-catalyzed hydroboration of pyridines with borane. In this reaction, the active catalytic species is considered to be an alkaline earth metal hydride complex when the corresponding alkaline earth metal is used as the catalyst. The theoretical results reveal that initiation of the catalytic cycle is hydride transfer to generate a magnesium hydride complex when ß-diimine alkylmagnesium is used as a pre-catalyst. The magnesium hydride complex can undergo coordination of the pyridine reactant followed by hydride transfer to form a dearomatized magnesium pyridine intermediate. Coordination of borane and hydride transfer from borohydride to magnesium then give the hydroboration product and regenerate the active magnesium hydride catalyst. The rate-determining step of the catalytic cycle is hydride transfer to pyridine with a free energy barrier of 29.7 kcal/mol. Other alkaline earth metal complexes, including calcium and strontium complexes, were also considered. The DFT calculations show that the corresponding activation free energies for the rate-determining step of this reaction with calcium and strontium catalysts are much lower than with the magnesium catalyst. Therefore, calcium and strontium complexes can be used as the catalyst for the reaction, which could allow mild reaction conditions.
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Although microRNA-155 (miR-155) is implicated in the pathogenesis of several fibrotic diseases, information regarding its functional role in renal fibrosis is limited. The current study aims to investigate the effects of miR-155 on renal fibrosis in unilateral ureteral occlusion (UUO) mice. MiR-155 level was significantly increased in renal tissues of UUO mice and TGF-ß1-treated HK2 cells. Masson's trichrome staining showed that delivery of adeno-associated virus encoding miR-155 inhibitor led to a decrease in renal fibrosis induced by UUO. The increased expression of plasminogen activator inhibitor type 1, collagen III and collagen IV was also inhibited after miR-155 inhibition. In addition, miR-155 knockdown also prevented TGF-ß1-induced epithelial-mesenchymal transition, concomitantly with a restoration of E-cadherin expression and a decrease of vimentin expression. Computational analysis revealed that miR-155 directly targets at 3'UTR of PDE3A. Overexpression of miR-155 suppressed the luciferase activity and protein expression of PDE3A, whereas inhibition of miR-155 increased PDE3A luciferase activity and expression. Furthermore, miR-155 inhibited TGF-ß1-induced the increase of TGF-ß1 expression and Smad-2/3 phosphorylation in HK2 cells. In contrast, knockdown of PDE3A reversed the effect of miR-155 inhibition on TGF-ß1 expression. This study demonstrates that knockdown of miR-155 attenuates renal fibrosis via inhibiting TGF-ß1/Smad signaling activation by targeting the upstream molecule PDE3A. This study suggests that miR-155 inhibition may be a novel therapeutic approach for preventing fibrotic kidney diseases.
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Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/metabolismo , Nefropatias/genética , Nefropatias/patologia , Rim/patologia , MicroRNAs/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Sequência de Bases , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/genética , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal , Fibrose , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Reprodutibilidade dos Testes , Obstrução Ureteral/genética , Obstrução Ureteral/patologiaRESUMO
Biomass energy is being industrialized rapidly in China in recent years, whereas, research on energy grass is still in primary stage. Only if near-infrared spectroscopy mode was constructed which was used to predict the lignin, cellulose and hemicellulose contents in energy crop, the varieties screening, performance evaluation and on-line control of industrialization would be facilitated. In this study, the prediction model for quality indices (cellulose, hemicellulose, lignin and ash) of four energy grass (Miscanthus) was built using Fourier transform near-infrared (FT-NIR) spectroscopy combined with partial least squares regression (PLSR), and the impacts exerted by particle size on the model were also revealed. The results showed that (1) the root mean error of cross validation (RMSECV) of cellulose, hemicelluloses and lignin contents were 1.35% (R = 0.88), 0.39% (R = 0.91) and 0.35 (R2 = 0.80), respectively in stalk and 0.72% (R = 0.88), 0.85% (R2 = 0.85) and 0.44 (R2 = 0.87), respectively in leaf. The model showed good performance in prediction of corresponding contents in unknown samples, however, no satisfying performance in ash content. (2) Both 2 mm and 0.5 mm grades of particle size can meet accuracy requirements of the model. But considering the time and labor cost, 2 mm grade was suggested for model building.
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Biocombustíveis , Celulose/química , Lignina/química , Polissacarídeos/química , China , Produtos Agrícolas/química , Espectroscopia de Luz Próxima ao InfravermelhoRESUMO
OBJECTIVE: To summarize the clinical characteristics of Bartter syndrome and investigate its pathogenesis. METHODS: The clinical data of 6 cases of Bartter syndrome at our hospital from November 2006 to May 2010 were analyzed retrospectively. RESULTS: The onset age of Bartter syndrome was 13-35 years old. The main symptoms included weakness (6/6), paralysis (1/6), numbness (5/6) and tetany (4/6). All patients had normal blood pressure. The biochemical tests showed persistent hypokalemia, metabolic alkalosis (6/6) and hyperreninemia. The pathological examination of deltoid muscle biopsy showed the swelling, degeneration and necrosis of myocytes and the deposition of immunocomplex in myolemma. And the pathological examination of renal biopsy showed the hyperplasia of juxtaglomerular apparatus (5/6) and the deposition of immunocomplex. All symptoms were relieved after a therapy of potassium supplementation or a combination of indomethacin, spironolactone and immunosuppressant. CONCLUSION: When such clinical features as weakness, paralysis, tetany, hypokalemic alkalosis and normotension are encountered, Bartter syndrome should be suspected. Serum electrolytes, blood gas analysis and activation of the renin-angiotensin-aldosterone system should be examined for a definite diagnosis. The treatment of choice includes potassium and magnesium supplementation or in combination with prostaglandin synthetase inhibitor, aldosterone antagonist and immunosuppressant. Immunologic mechanism may participate in the course of Bartter syndrome.
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Síndrome de Bartter/patologia , Adolescente , Adulto , Biópsia , Feminino , Humanos , Masculino , Sistema Renina-Angiotensina , Estudos Retrospectivos , Adulto JovemRESUMO
OBJECTIVE: To determine the possible myocilin molecular genetic defect underlying POAG in China and to identify the pathogenic mutation causing the disease. METHODS: The majority of 1 branch of a large Chinese POAG family were personally examined by two senior ophthalmologists. The diagnoses were made by both doctors according to the signs of elevated intraocular pressure, glaucomatous optic neuropathy and glaucomatous visual field defect. All coding sequences of the myocilin gene plus the flanking sites were amplified by polymerase chain reaction (PCR) using genomic DNA from all examined family members followed by sequencing of the PCR products. One hundred normal control subjects were screened by single strand confirmational polymorphism analysis for the mutation. RESULTS: This Chinese pedigree exhibited autosomal dominant mode of inheritance. The onset age ranged from 26 to 59 years. A novel disease-causing missense mutation T455K in the third exon of the myocilin gene was identified in all affected family members, all glaucoma suspects and 4 individuals who have not shown apparently signs of glaucoma. None of the subjects without the mutation had glaucoma. Affected individuals with the T455K mutation showed variable onset between 26 and 59 years of age. Filtering surgery was performed on all of 7 affected family members. The T455K mutation in myocilin gene was not found in the normal controls. A previously reported polymorphism IVS2+35(A to G)was detected in 4 individuals. CONCLUSION: The novel myocilin sequence alteration T455K that is highly associated with the development of glaucoma and locates in a very conserved residue is proven to be a disease-causing missence mutation. All affected individuals and all POAG suspects in this family are identified to have this mutation. The mutation in this family is associated with a phenotype characterized by mix-onset open angle glaucoma and associated with a high penetrance. It is important for the mutation screening and periodical checkups of presymptomatic individuals belonging to the family of a POAG patient with T455K mutation.