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Adjusting the electronic state of noble metal catalysts on a nanoscale is crucial for optimizing the performance of nanocatalysts in many important environmental catalytic reactions, particularly in volatile organic compound (VOC) combustion. This study reports a novel strategy for optimizing Pt catalysts by modifying their electronic structure to enhance the electron density of Pt. The research illustrates the optimal 0.2Pt-0.3W/Fe2O3 heterostructure with atomic-thick WO3 layers as a bulking block to electronically modify supported Pt nanoparticles. Methods such as electron microscopy, X-ray photoelectron spectroscopy, and in situ Fourier transform infrared spectroscopy confirm Pt's electron-enriched state resulting from electron transfer from atomic-thick WO3. Testing for benzene oxidation revealed enhanced low-temperature activity with moderate tungsten incorporation. Kinetic and mechanistic analyses provide insights into how the enriched electron density benefits the activation of oxygen and the adsorption of benzene on Pt sites, thereby facilitating the oxidation reaction. This pioneering work on modifying the electronic structure of supported Pt nanocatalysts establishes an innovative catalyst design approach. The electronic structure-performance-dependent relationships presented in this study assist in the rational design of efficient VOC abatement catalysts, contributing to clean energy and environmental solutions.
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The saponin-enriched extract from Celosiae Semen is a promising resource owing to its lipid-lowering activity. However, triterpenoid saponins are difficult to extract owing to their high molecular weight and strong water solubility. The aim of this paper was to explore an eco-friendly and effective technology of extraction and enrichment of total triterpenoid saponins to obtain high lipid-lowering fractions. Initially, Box-Behnken design experiments were employed to optimize the heat reflux extraction process on the basic of mono-factor experiments. Afterwards, the crude extract was further purified using D-101 resin, and the purification parameters were investigated based on adsorption/desorption experiments and biological activity assay. Under optimal conditions, the purity of the finally obtained total triterpenoid saponins was increased by 7.28-fold. The lipid-lowering activities of the six main triterpenoid saponins were evaluated in HepG2 cells induced by palmitic acid. The results of Oil Red O staining showed that the compounds all exhibited potential lipid-lowering activity. The structure-activity relationship analysis suggested that the oligosaccharide chain at C-28 played an essential role in their lipid-lowering activity and the substituent group at C-23 site also showed important effects. The optimal extraction and purification methods may facilitate the utilization of Celosiae Semen for the industrial production as a functional food and drug.
Assuntos
Amaranthaceae , Metabolismo dos Lipídeos , Saponinas/química , Saponinas/farmacologia , Triterpenos/química , Amaranthaceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Humanos , Células Hep G2 , Etanol/químicaRESUMO
BACKGROUND: Toxic components frequently exhibit unique characteristics and activities, offering ample opportunities for the advancement of anti-cancer medications. As the main hepatotoxic component of Dioscorea bulbifera L. (DB), Diosbulbin B (DIOB) has been widely studied for its anti-tumor activity at nontoxic doses. However, the effectiveness and mechanism of DIOB against non-small cell lung cancer (NSCLC) remains unclear. PURPOSE: To evaluate the anti-NSCLC activity of DIOB and to elucidate the specific mechanism of action. METHOD: The effect of DIOB on NSCLCL in vitro was evaluated through CCK8, colony formation, and flow cytometry. The in vivo efficacy and safety of DIOB in treating NSCLC were assessed using various techniques, including HE staining, tunel staining, immunohistochemistry, and biochemical index detection. To understand the underlying mechanism, cell transfection, western blotting, molecular docking, cellular thermal shift assay (CESTA), and surface plasmon resonance (SPR) were employed for investigation. RESULTS: DIOB effectively hindered the progression of NSCLC both in vitro and in vivo settings at a no-observed-adverse-effect concentration (NOAEC) and a safe dosage. Specifically, DIOB induced significant G0/G1 phase arrest and apoptosis in A549, PC-9, and H1299 cells, while also notably inhibiting the growth of subcutaneous tumors in nude mice. Mechanistically, DIOB could directly interact with oncogene Yin Yang 1 (YY1) and inhibit its expression. The reduction in YY1 resulted in the triggering of the tumor suppressor P53, which induced cell cycle arrest and apoptosis in NSCLC cells by inhibiting the expression of Cyclin A2, B2, CDK1, CDK2, CDK4, BCL-2, and inducing the expression of BAX. In NSCLC cells, the induction of G0/G1 phase arrest and apoptosis by DIOB was effectively reversed when YY1 was overexpressed or P53 was knocked down. Importantly, we observed that DIOB exerted the same effect by directly influencing the expression of YY1-regulated c-Myc and BIM, particularly in the absence of P53. CONCLUSION: For the inaugural investigation, this research unveiled the anti-NSCLC impact of DIOB, alongside its fundamental mechanism. DIOB has demonstrated potential as a treatment agent for NSCLC due to its impressive efficacy in countering NSCLC.
Assuntos
Apoptose , Carcinoma Pulmonar de Células não Pequenas , Pontos de Checagem do Ciclo Celular , Compostos Heterocíclicos de 4 ou mais Anéis , Neoplasias Pulmonares , Camundongos Nus , Fator de Transcrição YY1 , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Apoptose/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Animais , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Antineoplásicos Fitogênicos/farmacologia , Dioscorea/química , Camundongos , Camundongos Endogâmicos BALB C , Masculino , Simulação de Acoplamento Molecular , Células A549 , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
An estimated 694,550 United States service members were actively deployed to the Persian Gulf from 1990-1991. Many veterans who were deployed developed Persian Gulf War Syndrome along with chronic gastrointestinal symptoms after returning from the Persian Gulf. Our objective in this study was to determine the phenotypic expression of gastrointestinal symptom complexes in previously healthy veterans who had been stationed in the Persian Gulf. One hundred and four consecutive veterans (88 males, 16 females) who had previously been deployed in 1990-91 were evaluated for their bowel habits and gastrointestinal symptoms. A workup was completed to find identifiable causes of their symptoms and all veterans were asked to do a modified version of the Bowel Disease Questionnaire symptom survey. None of the veterans reported gastrointestinal symptoms before deployment. During deployment to the Persian Gulf: 22 veterans (21%) developed irritable bowel syndrome; 17 (16%) developed dyspepsia; 50 (48%) developed diarrhea; 11 (11%) developed bloating; and 4 (4%) developed constipation. The results of the current study suggest that the development of irritable bowel syndrome, dyspepsia, diarrhea, bloating, and constipation is frequently seen in deployed Gulf War Veterans and the gastrointestinal symptoms commonly persist upon returning home. These novel findings are very important for currently deployed veterans who are serving in the Middle East and are at a high risk of developing gastrointestinal disorders.
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The gut microbiome plays pivotal roles in various physiological and pathological processes, with key metabolites including short chain fatty acids (SCFAs), bile acids (BAs), and tryptophan (TRP) derivatives gaining significant attention for their diverse physiological roles. However, quantifying these metabolites presents challenges due to structural similarity, low abundance, and inherent technical limitations in traditional detection methods. In this study, we developed a precise and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method utilizing a chemical isotope derivatization technique employing 4-(aminomethyl)-N,N-dimethylaniline-d0/d6 (4-AND-d0/d6) reagents to quantify 37 typical gut microbiome-derived metabolites. This method achieved an impressive 1500-fold enhancement in sensitivity for detecting metabolites, compared to methods using non-derivatized, intact molecules. Moreover, the quantitative accuracy of our chemical isotope derivatization strategy proved comparable to the stable isotope labeled internal standards (SIL-IS) method. Subsequently, we successfully applied this newly developed method to quantify target metabolites in plasma, brain, and fecal samples obtained from a neonatal hypoxic-ischemic encephalopathy (HIE) rat model. The aim was to identify crucial metabolites associated with the progression of HIE. Overall, our sensitive and reliable quantification method holds promise in elucidating the role of gut microbiome metabolites in the pathogenesis of various diseases.
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Fezes , Microbioma Gastrointestinal , Hipóxia-Isquemia Encefálica , Animais , Masculino , Ratos , Animais Recém-Nascidos , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/química , Encéfalo/metabolismo , Modelos Animais de Doenças , Ácidos Graxos Voláteis/metabolismo , Ácidos Graxos Voláteis/análise , Fezes/microbiologia , Fezes/química , Microbioma Gastrointestinal/fisiologia , Hipóxia-Isquemia Encefálica/metabolismo , Marcação por Isótopo/métodos , Espectrometria de Massa com Cromatografia Líquida , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem/métodosRESUMO
Fulvic acid (FA) is a representative photosensitive dissolved organic matter (DOM) compound that occurs naturally in paddy soils. In this study, the effect of a FA + nitrate treatment (0, 4 and 8 mg/L FA + 20 mmol/L nitrate) on denitrification and As(III) immobilization in flooded paddy soils was assessed under dark and intermittently illuminated conditions (12 h light+12 h dark). The FA input stimulated denitrification in illuminated soils (~100 % of nitrate removal within 6 days) compared to dark conditions (~92 % nitrate removal after 6 days). Meanwhile, As(III) (initial concentration of 0.1 mmol/L) was nearly completely immobilized (~100 %) under illuminated conditions after 4 days for the FA + nitrate treatment compared to 90- 93 % retention in the dark. Denitrification and As immobilization were positively related to the FA dosage in the illuminated assays. The stronger denitrification in illuminated soils was ascribed to denitrifiers harvesting photoelectrons from photosensitive substrates/semiconducting minerals. FA addition also increased the activities of denitrifying enzymes (e.g., NAR, NIR and NOR) and the denitrification electron transport system by nearly 0.6-0.7 and 1.5-1.8 times that of the nitrate-alone treatment under illuminated and dark conditions, thereby fostering stronger denitrification. Upon irradiation, As(III) immobilization was not only stimulated by the interactions with the denitrification pathway whereby As(III) acts as an electron donor for denitrifiers, but was also modulated by Fe(III)/oxidative reactive species-derived photooxidation of As(III). Moreover, the FA + nitrate treatment promoted the enrichment of metal-oxidizing bacteria (e.g., Stenotrophomonas and Acidovorax) that are responsible for nitrate-dependent As(III)/Fe(II) oxidation. The results of this study enhance our understanding of interactions among the biogeochemical cycles of As, Fe, N and C, which are intricately linked by a biophotoelectrochemical pathway in flooded paddy soils.
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Benzopiranos , Desnitrificação , Nitratos , Nitratos/metabolismo , Compostos Férricos , Solo/química , OxirreduçãoRESUMO
This study aimed to characterize the composition of intestinal and nasal microbiota in septic patients and identify potential microbial biomarkers for diagnosis. A total of 157 subjects, including 89 with sepsis, were enrolled from the affiliated hospital. Nasal swabs and fecal specimens were collected from septic and non-septic patients in the intensive care unit (ICU) and Department of Respiratory and Critical Care Medicine. DNA was extracted, and the V4 region of the 16S rRNA gene was amplified and sequenced using Illumina technology. Bioinformatics analysis, statistical processing, and machine learning techniques were employed to differentiate between septic and non-septic patients. The nasal microbiota of septic patients exhibited significantly lower community richness (P = 0.002) and distinct compositions (P = 0.001) compared to non-septic patients. Corynebacterium, Staphylococcus, Acinetobacter, and Pseudomonas were identified as enriched genera in the nasal microbiota of septic patients. The constructed machine learning model achieved an area under the curve (AUC) of 89.08, indicating its efficacy in differentiating septic and non-septic patients. Importantly, model validation demonstrated the effectiveness of the nasal microecological diagnosis prediction model with an AUC of 84.79, while the gut microecological diagnosis prediction model had poor predictive performance (AUC = 49.24). The nasal microbiota of ICU patients effectively distinguishes sepsis from non-septic cases and outperforms the gut microbiota. These findings have implications for the development of diagnostic strategies and advancements in critical care medicine.IMPORTANCEThe important clinical significance of this study is that it compared the intestinal and nasal microbiota of sepsis with non-sepsis patients and determined that the nasal microbiota is more effective than the intestinal microbiota in distinguishing patients with sepsis from those without sepsis, based on the difference in the lines of nasal specimens collected.
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Bactérias , Biomarcadores , Fezes , Unidades de Terapia Intensiva , Microbiota , RNA Ribossômico 16S , Sepse , Humanos , Sepse/diagnóstico , Sepse/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , RNA Ribossômico 16S/genética , Biomarcadores/análise , Bactérias/isolamento & purificação , Bactérias/genética , Bactérias/classificação , Fezes/microbiologia , Adulto , Aprendizado de Máquina , Microbioma Gastrointestinal , Nariz/microbiologia , Corynebacterium/isolamento & purificação , Corynebacterium/genética , Acinetobacter/isolamento & purificação , Acinetobacter/genética , Idoso de 80 Anos ou mais , Staphylococcus/isolamento & purificação , Staphylococcus/genética , Pseudomonas/isolamento & purificação , Pseudomonas/genéticaRESUMO
Abstract Objective: To observe the effects of preoperative right stellate ganglion block on perioperative atrial fibrillation in patients undergoing lung lobectomy. Methods: Two hundred patients who underwent a scheduled lobectomy were randomly divided into the S and C groups. The S group was injected with 4 mL of 0.2% ropivacaine under ultrasound guidance, and the C group did not receive stellate ganglion block. The patients underwent continuous ECG monitoring, and the incidences of atrial fibrillation and other types of arrhythmias were recorded from the start of surgery to 24 hours after surgery. Results: The respective incidences of atrial fibrillation in the S group and the C group were 3% and 10% (p = 0.045); other atrial arrhythmias were 20% and 38% (p = 0.005); and ventricular arrhythmia were 28% and 39% (p = 0.09). Conclusions: The results of the study indicated that preoperative right stellate ganglion block can effectively reduce the incidence of intraoperative and postoperative atrial fibrillation.
Resumo Objetivo: Observar os efeitos do bloqueio do gânglio estrelado na fibrilação atrial no período perioperatório em pacientes submetidos a lobectomia pulmonar. Método: Duzentos pacientes programados para lobectomia foram divididos aleatoriamente nos grupos S e C. O grupo S recebeu infusão de 4 mL de ropivacaína a 0,2% orientada por ultrassom e o grupo C não foi submetido a bloqueio do gânglio estrelado. Os pacientes foram submetidos à monitoração contínua de ECG, e as incidências de fibrilação atrial e outros tipos de arritmias foram registradas do início da cirurgia até 24 horas depois da cirurgia. Resultados: As incidências de fibrilação atrial no grupo S e no grupo C foram 3% e 10%, respectivamente (p = 0,045); as de outras arritmias atriais foram 20% e 38% (p = 0,005); e de arritmias ventriculares, 28% e 39% (p = 0,09). Conclusões: Os resultados do estudo indicaram que o bloqueio do gânglio estrelado no pré-operatório pode ser efetivo na redução da incidência de fibrilação atrial nos períodos intra- e pós-operatório.