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Selective aerobic oxidation of alcohols in batch and flow can be realized under light irradiation, utilizing disulfide as the photocatalyst, and a variety of primary and secondary alcohols were converted to the corresponding aldehydes or ketones in up to 99% yield and high selectivity. The reaction efficiency could be increased even further by combining a continuous-flow strategy. Detailed mechanistic studies have also been achieved to determine the role of oxygen and disulfides in this oxidation.
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Rheumatoid arthritis (RA) is an autoimmune disease that is currently incurable. Inhibition of inflammation can prevent the deterioration of RA. 2-[(Aminocarbonyl)amino]-5-(4-fluorophenyl)-3-thiophenecarboxamide (TPCA-1) suppresses inflammation via the inhibition of nuclear factor-κ (NF-κB) signaling pathway. Gold-based therapies have been used to treat inflammatory arthritis since the 1940s. Hyaluronic acid (HA) is a targeting ligand for CD44 receptors overexpressed on activated macrophages. Therefore, a combined therapy based on TPCA-1, gold, and HA was explored for the treatment of RA in this study. We used gold nanocages (AuNCs) to load TPCA-1 and modified the TPCA-1 (T) loaded AuNCs with HA and peptides (P) to construct an anti-inflammatory nanoparticle (HA-AuNCs/T/P). An adjuvant-induced arthritis (AIA) mice model was used to investigate the in vivo anti-inflammatory efficacy of HA-AuNCs/T/P. In vivo distribution results showed that HA-AuNCs/T/P had increased and prolonged accumulation at the inflamed paws of AIA mice. Treatment by the HA-AuNCs/T/P suppressed joint swelling and alleviated cartilage and bone damage. By loading to HA-AuNCs/T/P, the effective concentration of TPCA-1 was greatly reduced from 20 to 0.016 mg/kg mice. This study demonstrated that HA-AuNCs/T/P could effectively suppress inflammation and alleviate the symptoms of AIA mice, suggesting a great potential of HA-AuNCs/T/P for the treatment of RA.
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Amidas/química , Artritis Reumatoide/tratamiento farmacológico , Oro/química , Nanopartículas del Metal/uso terapéutico , Tiofenos/química , Animales , Artritis Experimental/tratamiento farmacológico , Ácido Hialurónico/administración & dosificación , Masculino , Nanopartículas del Metal/administración & dosificación , Nanopartículas del Metal/química , RatonesRESUMEN
A series of C-2' modified cinchonine-derived phase-transfer catalysts were synthesized and used in the enantioselective photo-organocatalytic aerobic oxidation of ß-dicarbonyl compounds with excellent yields (up to 97%) and high enantioselectivities (up to 90% ee). Furthermore, the reaction was carried out in a flow photomicroreactor, in which the heterogeneous gas-liquid-liquid asymmetric photocatalytic oxidation reaction was performed affording good yields (up to 97%) and enantioselectivities (up to 86% ee) within 0.89 min.
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An aerobic photoepoxidation of α,ß-unsaturated ketones driven by visible light in the presence of tetramethylguanidine (3b), tetraphenylporphine (H2TPP), and molecular oxygen under mild conditions was revealed. The corresponding α,ß-epoxy ketones were obtained in yields of up to 94% in 96 h. The reaction time was shortened to 4.6 h by flow synthesis. The mechanism related to singlet oxygen was supported by experiments and density functional theory (DFT) calculations.
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As reported, the persistent toxic and harmful pollutant bisphenol A (BPA) from industrial emissions has been consistently found in aquatic environments inhabited by humans. Periodate (PI)-based advanced oxidation processes (AOPs) have been employed to degrade BPA, although activating PI proves more challenging compared to other oxidants. A novel nano iron metal catalyst, sulfided nanoscale iron-nickel bimetallic nanoparticle supported on biocarbon (S-(nFe0-Ni)/BC) was synthesized and utilized to activate PI for the removal of BPA. The morphology, structure, and composition of S-(nFe0-Ni)/BC were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy-energy dispersive spectrometer (SEM-EDS), and fourier-transform infrared spectrum (FTIR). The catalyst demonstrates an excellent ability to activate PI, achieving a BPA removal efficacy of 86.4%, accompanied by a 33% reduction in total organic carbon (TOC) in the {S-(nFe0-Ni)/BC}/PI system. BPA degradation exhibited a significant change at the 5-min mark. In the first stage (0-5 min), nonlinear dynamic fitting research, combined with scavenging experiments, unveiled the competitive degradation of pollutants primarily driven by iodate radical ( IO 3 · ), singlet oxygen 1 O 2 , and hydroxyl radical ( · OH ). The competitive dynamics aligned with the ExpAssoc model. The contribution rates of different active species during the second stage (5-120 min) were calculated. The contributions of main species to BPA removal follow the order of IO 3 · > 1 O 2 > · OH throughout the entire process. The influence of various parameters, such as the dosage of S-(nFe0-Ni)/BC, initial PI concentration, BPA concentration, pH, temperature, and the presence of coexisting anions, was also examined. Finally, a plausible reaction mechanism in the system is proposed, suggesting that the {S-(nFe0-Ni)/BC}/PI system involves a heterogeneous synergistic reaction occurring primarily on the surface of S-(nFe0-Ni)/BC. Therefore, this study proposes a promising approach for PI-based AOPs to degrade organic pollutants, aiming to mitigate the irreversible harm caused by such pollutants to organisms and the environment.
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Compuestos de Bencidrilo , Hierro , Ácido Peryódico , Fenoles , Contaminantes Químicos del Agua , Humanos , Hierro/química , Temperatura , Contaminantes Químicos del Agua/análisisRESUMEN
Purpose: In this study, we aimed to determine the transmission pattern of multidrug-resistant tuberculosis (MDR-TB) isolates circulating in Jiangxi Province with whole-genome sequencing (WGS). In addition, we also sought to describe mutational resistome of MDR-TB isolates. Patients and Methods: A total of 115 MDR-TB isolates determined by the phenotypic proportion method of drug susceptibility testing between January 2018 and December 2022 from provincial drug surveillance (DRS) in Jiangxi were included in our analysis. The demographic data and treatment history were extracted from the National TB Registry System. WGS was used to analyze the genotypic characteristics of drug resistance and transmissions. Results: About 62.6% of MDR-TB strains were isolated from cases that received previous anti-tuberculosis treatment. According to the WGS results, 96.5% were genotypic MDR-TB, and more than half of MDR-TB isolates tested were also resistant to streptomycin (59.1%), ethambutol (56.5%), and fluroquinolones (53.0%), while resistance to cycloserine and linezolid was lowest, only in two (1.7%) and one (0.9%) isolate, respectively. Ser450Leu in rpoB (57.9%), Ser315Thr in katG (74.1%), Met306Val in embB (40.0%), Lys43Arg in rpsL (75.0%), Ala90Val in gyrA (32.8%) were predominant mutant types among the rifampin-, isoniazid-, ethambutol-, streptomycin-, fluoroquinolones-resistant isolates, respectively. Lineage 2 (East Asian genotype) occurred at the highest frequency with 97 cases (84.3%), followed by lineage 4 (Euro-American genotype) with 18 cases (15.7%). Additionally, 5 clusters consisting of 10 isolates were identified in the present study, demonstrating a clustering rate of 8.7%. Conclusion: MDR/Rifampicin-Resistant (RR)-TB epidemic in this region is driven by lineage 2 clade that also show higher resistance to other anti-tuberculosis drugs. Lower cluster rates compared with a relatively higher proportion of new MDR-TB cases indicate that a considerable number of MDR-TB cases remain undiagnosed.
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OBJECTIVE: Benign nerve sheath tumors (BNSTs) present diagnostic challenges due to their heterogeneous nature. This study aimed to determine the significance of NRG1 as a novel diagnostic biomarker in BNST, emphasizing its involvement in the PI3K-Akt pathway and tumor immune regulation. METHODS: Differential genes related to BNST were identified from the GEO database. Gene co-expression networks, protein-protein interaction networks, and LASSO regression were utilized to pinpoint key genes. The CIBERSORT algorithm assessed immune cell infiltration differences, and functional enrichment analyses explored BNST signaling pathways. Clinical samples helped establish PDX models, and in vitro cell lines to validate NRG1's role via the PI3K-Akt pathway. RESULTS: Nine hundred eighty-two genes were upregulated, and 375 downregulated in BNST samples. WGCNA revealed the brown module with the most significant difference. Top hub genes included NRG1, which was also determined as a pivotal gene in disease characterization. Immune infiltration showed significant variances in neutrophils and M2 macrophages, with NRG1 playing a central role. Functional analyses confirmed NRG1's involvement in key pathways. Validation experiments using PDX models and cell lines further solidified NRG1's role in BNST. CONCLUSION: NRG1 emerges as a potential diagnostic biomarker for BNST, influencing the PI3K-Akt pathway, and shaping the tumor immune microenvironment.
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Neoplasias de la Vaina del Nervio , Fosfatidilinositol 3-Quinasas , Humanos , Proteínas Proto-Oncogénicas c-akt , Algoritmos , Biomarcadores , Microambiente Tumoral , Neurregulina-1/genéticaRESUMEN
The synthesis of low-temperature poly(heptazine imide) (PHI) presents a significant challenge. In this context, we have developed a novel low-temperature synthesis strategy for PHI in this work. This strategy involves the introduction of Na+ ions, which etch and disrupt the conjugated structure of carbon nitride (CN) during assisted thermal condensation. This disruption leads to the partial decomposition of the heptazine ring structure, resulting in the formation of C≡N functionalities on the CN surface, which are enriched with hydroxyl groups and undergo cyano modification. The formation of heterojunctions between CN and ZnO, which facilitate charge transfer along an immobilization pathway, accelerated charge transfer processes and improved reactant adsorption as well as electron utilization efficiency. The resulting catalyst was employed for the room temperature, atmospheric pressure, and solvent-free photocatalytic selective oxidation of cumene (CM), achieving a cumene conversion rate of 28.7% and a remarkable selectivity of 92.0% toward the desired product, cumene hydroperoxide (CHP). Furthermore, this CHP induced oxidative reactions, as demonstrated by the successful oxidation of benzylamine to imine and the oxidation of sulfide to sulfoxide, both yielding high product yields. Additionally, the utilization of a continuous-flow device significantly reduces the reaction time required for these oxidation processes. This work not only introduces an innovative approach to environmentally friendly, sustainable, clean, and efficient PHI synthesis but also underscores the promising potential and advantages of carbon nitride-based photocatalysts in the realm of sustainable and green organic transformations.
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Inflammatory diseases are usually featured with relatively high level of reactive oxygen species (ROS). The excess ROS facilitate the polarization of microphages into proinflammatory M1 phenotype, and cause DNA damage, protein carbonylation, and lipid peroxidation, resulting in further deterioration of inflammatory diseases. Therefore, alleviating oxidative stress by ROS scavenging has been an effective strategy for reversing inflammation. Inspired by the natural antioxidant enzymes, electron transfer-based artificial antioxidant nanozymes have been emerging therapeutics for the treatment of inflammatory diseases. The present review starts with the basic knowledge of ROS and diseases, followed by summarizing the possible active centers for the preparation of antioxidant nanozymes. The strategies for the design of antioxidant nanozymes on the purpose of higher catalytic activity are provided, and the applications of the developed antioxidant nanozymes on the therapy of inflammatory diseases are discussed. A perspective is included for the design and applications of artificial antioxidant nanozymes in biomedicine as well.
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Antioxidantes , Electrones , Antioxidantes/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Estrés OxidativoRESUMEN
The selective oxidation of benzyl C-H bonds of alkyl aromatic hydrocarbons under solvent-free conditions by using heterogeneous catalysis is a challenging task. In this work, we designed a carbon nitride photocatalyst with a high charge separation efficiency and a directed charge transfer path, which was doped with Ni and Br in the carbon nitride skeleton. Br was deposited directionally onto the electron-rich Ni surface traps to form a bond with Ni, which acted as a charge transfer bridge connecting CN and Br, resulting in a bridging effect. Photogenerated electrons were transferred from Ni target to Br, and electrons were aggregated to form a directional charge transfer path, thereby enhancing the photocatalytic performance of CN. The photocatalyst was utilized for the selective oxidation of ethylbenzene at room temperature, atmospheric pressure, and solvent-free conditions. Under batch conditions simulating solar irradiation, the conversion of ethylbenzene was 43.3% and the selectivity of the product acetophenone was up to 92.0%. With the continuous flow strategy, the conversion of ethylbenzene was increased to 52.4 and 48.1%, respectively, while the selectivity reached 92.7 and 91.0%, and the reaction time was reduced from 24 to 2.1 h. The catalyst was also found to be broadly applicable for the selective oxidation of C-H bonds in the benzyl position of alkyl aromatic hydrocarbons.
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At present, with the development of high technology and materials science, the traditional laser processing (NLP) method is no longer sufficient for the preparation of special surface profiles in the field of cutting-edge manufacturing. Ultrasonic vibration assisted laser processing (UVLP) is gradually being developed by researchers, but is largely experimental study in nature. In this paper, a mathematical model of the transverse ultrasonic composite laser ablation trajectory of metals is developed, and the feasibility of the model is verified by numerical simulations and experiments by using aluminum as the base material. Error rates for ablation widths and trajectory cycle times range from 2.18% to 6.50%. The error of the crater lap rate is 3.88%-19.62%. The influence of ultrasonic and laser frequencies on the ablation trajectories is analyzed. The frequency selection rules for the preparation of special morphologies are given. This study presents a theoretical model of a new processing method, which has a guiding significance for the parameters selection of laser processing and the special surface morphology preparation.
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Rayos Láser , Metales , Ondas Ultrasónicas , Ultrasonido , Modelos TeóricosRESUMEN
The mechanism of how oxygen affects cumene autoxidation related to temperature is still bewildering. Kinetic analysis of cumene autoxidation with air at a pressure of 1.0 atm was investigated by experiments and variational transition state theory/DFT. Oxygen was the limiting factor for cumene autoxidation above 100 °C, although it had negligible impacts on cumene autoxidation at 70-100 °C. The kinetic analysis by VTST coupled with DFT calculations proved that {k 6,reverse[ROOâ¢]}/{k 7,forward[RH]0 [ROOâ¢]} > 103 (70-120 °C), suggesting that ROO⢠tended to decompose back to R⢠and O2 rapidly, whereas it was much slower for ROO⢠abstracting a hydrogen atom from RH to form ROOH. When the concentration of oxygen was higher than the critical value ([O2]critical), it could not significantly affect the equilibrium concentration of ROOâ¢, which in turn could not affect the autoxidation rate significantly. Besides, the critical oxygen concentration ([O2]critical) was exponentially related to 1/T, which was consistent with Hattori's experimental results.
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The oxidative cleavage of C=C bonds is an important chemical reaction, which is a popular reaction in the photocatalytic field. However, high catalyst-loading and low turnover number (TON) are general shortcomings in reported visible-light-driven reactions. Herein, the direct oxidative cleavage of C=C bonds through water-soluble CdSe quantum dots (QDs) is described under visible-light irradiation at room temperature with high TON (up to 3.7×104 ). Under the same conditions, water-soluble CdSe QDs could also oxidize sulfides to sulfoxides with 51-84 % yields and TONs up to 3.4×104 . The key features of this photocatalytic protocol include high TONs, wide substrates scope, low catalyst loadings, simple and mild reaction conditions, and molecular O2 as the oxidant.
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BACKGROUND: Early acute kidney injury (AKI) is a frequent fatal complication of severely burned patients. Although significant progress has been made in fluid resuscitation, intensive care, and renal replacement therapy (RRT) technology in recent years, the incidence and mortality rate in severely burned patients with AKI remains considerable. This study aims to provide theoretical evidence for prevention and treatment by investigating the clinical characteristics and risk factors influencing the incidence and severity of early AKI in severely burned patients. METHODS: This 3-year retrospective, single-center study was conducted in critically ill burned patients admitted to the Burn ICU at Guangzhou Red Cross Hospital of Jinan University. Patients whose age is older than 18 years with ≥30% burned total body surface area (TBSA) were enrolled in this study. Those patients who arrived at our burn ICU>72h after injury or died within 48h from arrival were excluded. Data of 128 patients were studied in the final. Demographic and injury details were recorded. KDIGO criteria were used to assess the incidence and severity of early AKI. Factors influencing early AKI were determined using univariate and multiple logistic regression analysis. RESULTS: Between January 2016 and December 2018, Data from 128 critically ill burned patients were available for analysis. The median age was 44.9±16.8 years; 68.8% of the patients were male. The median TBSA% was 60 (IQR, 41.3-80%). According to the KDIGO criteria, 36 patients (28.3%) developed early AKI, as follows: stage 1 AKI, 69.4% (25/36); stage 2 AKI, 13.9% (5/36); and stage 3 AKI, 16.7% (6/36). The incidence of early AKI was associated with TBSA%, full-thickness TBSA%, abbreviated burn severity index on admission (ABSI), inhalation injury, mechanical ventilation, cardiovascular complications, and rhabdomyolysis. Multiple logistic regression analysis indicate that TBSA% (OR=0.224, p=0.007), full-thickness TBSA% (OR=0.254, p=0.014), ABSI (OR=18.326, p=0.009), and rhabdomyolysis (OR=24.036, p=0.000) were independent risk factors for the occurrence of early AKI. Significant factors influencing the severity of early AKI included full-thickness body surface area burns, electrical burns, and rhabdomyolysis. Full-thickness TBSA% (OR=1.437, p=0.041) and rhabdomyolysis (OR=5.401, p=0.035) are associated with mortality. The risk of death due to the occurrence of AKI was 5.407 in the Cox model adjusted for TBSA%, full-thickness body surface area burns, ABSI and rhabdomyolysis. Three patients died, all of whom had stage 3 AKI, accounting for 8.3% (3/36) of AKI patients. The death rate of stage 3 AKI who did and did not receive early RRT was 33.3% and 66.7%, respectively. CONCLUSION: Rhabdomyolysis is an independent risk factor for early AKI and closely related to the severity of early AKI in critically ill burned patients. Although with a high incidence of early AKI in severely burned patients, most of them are mild. Early adequate fluid resuscitation, timely and effective escharotomy, reducing the incidence and severity of rhabdomyolysis, most of them can achieve a relatively good prognosis.
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Lesión Renal Aguda/epidemiología , Quemaduras/terapia , Rabdomiólisis/epidemiología , Lesión Renal Aguda/terapia , Adulto , Superficie Corporal , Quemaduras/complicaciones , Quemaduras/patología , Quemaduras por Electricidad/complicaciones , Quemaduras por Electricidad/patología , Quemaduras por Electricidad/terapia , Enfermedad Crítica , Femenino , Fluidoterapia , Humanos , Unidades de Cuidados Intensivos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Terapia de Reemplazo Renal , Rabdomiólisis/etiología , Factores de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
A novel and facile visible-light-mediated alkylation of indoles and nitroalkenes has been developed. In this protocol, rose bengal acts as a photosensitizer, and environmentally benign water was used as the green and efficient reaction medium. Indoles reacted smoothly with nitroalkenes under the irradiation of visible-light and generated corresponding 3-(2-nitroalkyl)indoles in moderate to good yields (up to 87%).
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Gold nanocages (AuNCs) are biocompatible and porous nanogold particles that have been widely used in biomedical fields. In this study, hyaluronic acid (HA) and peptide- modified gold nanocages (HA-AuNCs/T/P) loaded with 2-[(aminocarbonyl)amino]-5-(4-fluorophenyl)-3-thiophenecarboxamide (TPCA-1) were prepared to investigate their potential for combating inflammation. TPCA-1 was released from AuNCs, intracellularly when HA was hydrolyzed by hyaluronidase. HA-AuNCs/T/P show a much higher intracellular uptake than AuNCs/T/P, and exhibit a much higher efficacy on the suppression of tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) than free TPCA-1, suggesting great improvement to the anti-inflammatory efficacy of TPCA-1 through the application of AuNCs. HA-AuNCs/T/P can also reduce the production of reactive oxygen species in inflammatory cells. This study suggests that HA-AuNCs/T/P may be potential agents for anti-inflammatory treatment, and are worthy of further investigation.
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A visible light-mediated α-functionalization of 1,3-dicarbonyl compounds with switchable selectivity induced by disulfide is disclosed. Upon irradiation with visible light, the metal- and base-free α-hydroxylation or α-hydroxymethylation reaction proceeded smoothly through a disulfide-catalyzed oxidation under mild conditions. The combination of a continuous-flow strategy could further improve the reaction efficiencies.
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In this paper, the kinetics of bisphenol S (BPS) degradation in the presence of peroxydisulfate (PDS) or dissolved oxygen (DO) in ultrasound (US) system were investigated. For PDS (US/PDS), increased PDS concentration result in faster BPS degradation, but the enhancement was not remarkable with multiplying PDS dosages. Therefore, heterogeneous PDS activation model based on a Langmuir-type adsorption mechanism was proposed to explain the trait of BPS abatement. The equilibrium constant of PDS (KPDS) was calculated to be 2.91â¯×â¯10-4/µM, which was much lower than that of BPS, suggesting that PDS was hard to adsorb on the gas-liquid interface of the cavitation bubble following by activation. Besides, the formation of â¢OH and SO4â¢- in US/PDS system was reinvestigated. The result showed that SO4â¢- rather than â¢OH was the predominant radical, which was quite different from previous study. Dissolved oxygen largely improve the degradation of BPS in US system and â¢OH rather than O2â¢- was proved to be the main reactive oxygen species (ROS). The improvement of â¢OH generation possibly caused by the reaction of DO with â¢H so that it cannot recombine with â¢OH. The transformation of the BPS in US system mainly included BPS radical polymerization, hydroxylation and hydrolysis. Frustratingly, the acute toxicity assay of Vibrio fischeri suggests that the degradation products of BPS are more toxic. These results will improve the understanding on the activation mechanisms of PDS and the role of dissolved oxygen play in US. Further investigations may need to explore other treatment ways of BPS and evaluate the acute toxicity of degradation products.
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Oxígeno , Contaminantes Químicos del Agua , Oxidación-Reducción , Fenoles , SulfonasRESUMEN
The highly enantioselective α-hydroxylation of ß-keto esters using cumene hydroperoxide (CHP) as the oxidant was realized by a chiral (1S,2S)-cyclohexanediamine backbone salen-zirconium(IV) complex as the catalyst. A variety of corresponding chiral α-hydroxy ß-keto esters were obtained in excellent yields (up to 99%) and enantioselectivities (up to 98% ee). The zirconium-catalyzed enantioselective α-hydroxylation of ß-keto esters was scalable, and the zirconium catalyst was recyclable. The reaction can be performed in gram scale, and corresponding chiral products were acquired in 95% yield and 99% ee.