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Supported alloy catalysts play a pivotal role in many heterogeneous catalytic processes of socioeconomic and environmental importance. But the controlled synthesis of supported alloy nanoparticles with consistent composition and tight size distribution remains a challenging issue. Herein, a simple yet effective method for preparation of highly dispersed, homogeneously alloyed bimetallic nanoparticles on oxide supports is reported. This method is based on solid solution of metal cations in parent oxide and strong electrostatic adsorption of a secondary metal species onto the oxide surface. In the reductive annealing process, hydrogen spillover occurs from the surface metal with a higher reduction potential to the solute metal in solid solution, leading to metal exsolution and homogenous alloying of the metals on the oxide surface. The ceria-supported Ni-Pt alloy is chosen as a model catalyst and hydrazine monohydrate decomposition is chosen as a probe reaction to demonstrate this method, and particularly its advantages over the conventional impregnation and galvanic replacement methods. A systematic application of this method using different oxides and base-noble metal pairs further elucidates its applicability and generality.
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Nanopartículas , Óxidos , Ligas , Oxirredução , Metais , HidrogênioRESUMO
Preparation of biologically relevant 3-hydroxyisoindolinones from readily available 2-alkynylbenzamides is an appealing synthetic approach. However, such kinds of compounds preferably undergo O-attacked 5-exo-dig/6-endo-dig cyclizations. Herein, we report an electrochemically generated amidyl radical proceeding via a highly selective N-attacked 5-exo-dig radical cyclization to form 3-hydroxyisoindolinone derivatives. This reaction features simple operation, good selectivity, and broad substrate scope. Moreover, gram-scale preparation and synthetic elaborations imply the potential applicability of this protocol for the synthesis of diverse isoindolinone derivatives.
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CiclizaçãoRESUMO
Benzoxathiazine dioxide, as a bioisostere of the clinically widely used diazoxide, exhibits interesting biological activity. However, limited success has been achieved in terms of its concise and direct synthesis. We report herein a facile electrochemical migratory cyclization of N-acylsulfonamides to access a diverse array of benzoxathiazine dioxides. The inclusion of electrochemistry is crucial for realizing such a novel transformation, which is substantiated both by the experiments and density-functional-theory calculations.
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Ciclização , EletroquímicaRESUMO
The harmful effects of perfluorooctane sulfonate (PFOS) are of growing international concern. This paper aimed to gain an integrated understanding of fitness-related ecological end points, such as behavior, metabolism and swimming physiology, in juvenile Spinibarbus sinensis in response to PFOS toxicity at different temperatures. The fish were exposed to a range of PFOS concentrations (0, 0.32, 0.8, 2 and 5 mg/L) at different temperatures (18 and 28 °C) for 30 days. The effects on fish behavior, metabolic characteristics and aerobic swimming performance caused by PFOS at different temperatures were investigated. Our results showed that both PFOS and temperature had important influences on spontaneous swimming behavior, social interactions, routine metabolic rate (RMR), net energetic cost of transport (COTnet) and critical swimming speed (U crit) in fish. The lowest observed effect concentration for both U crit and RMR was 5 and 0.8 mg/L at 18 and 28 °C, respectively. We found that PFOS affected various behavioral and social end points and also appeared to affect metabolic rates and reduced U crit, likely as a result of increased COTnet, and that many of these effects also changed with respect to temperature. Our results further the understanding of the metabolic and behavioral toxicity of PFOS to aquatic organisms.
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Ácidos Alcanossulfônicos/toxicidade , Comportamento Animal/efeitos dos fármacos , Cyprinidae/fisiologia , Metabolismo Energético/efeitos dos fármacos , Fluorocarbonos/toxicidade , Natação/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Metabolismo Energético/fisiologia , TemperaturaRESUMO
A palladium-catalyzed enantioselective C-H arylation of N-(o-bromoaryl)-diarylphosphinic amides is described for the synthesis of phosphorus compounds bearing a P-stereogenic center. The method provides good enantioselectivities and high yields. The products were readily transformed into P-chiral biphenyl monophosphine ligands.
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This study aimed to identify gene expression profile in the rat brain resulting from acute alcohol intoxication (AAI). Eighteen SD rats were divided into the alcohol-treated group (n = 9) and saline control group (n = 9). Periorbital blood samples were taken to determine their blood alcohol content by gas chromatography. Tissue sections were analyzed by H and E staining and biochemical assays. Real-time reverse transcription PCR was used to validate microarray data. Statistical analysis was carried out using SPSS18.0 software (Version 18.0, SPSS Inc., Chicago, IL, USA). H and E staining demonstrated that alcohol-treated rats showed no obvious pathological changes in nerve cells compared with those in the control group. Biochemical tests revealed that alcohol-treated rats had lower superoxide dismutase activity than those in the control group (167.3 ± 10.3 U/mg vs. 189.2 ± 5.9 U/mg, P < 0.05). Furthermore, the malondialdehyde levels in alcohol-treated rats were higher than those in the control group (3.48 ± 0.24 mmol/mg vs. 2.51 ± 0.23 mmol/mg, P < 0.05). Microarray data presented 366 up-regulated genes and 300 down-regulated genes in the AAI rat brain. Gene ontology analysis identified 31 genes up-regulated and 39 down-regulated among all differentially expressed genes. Twenty-four pathways showed significant differences, including 12 pathways involved with up-regulated genes and 12 pathways involved with down-regulated genes. Selected genes showed significantly different expression in both alcohol-treated and control groups (P < 0.05). Gene expression analysis enabled clustering of alcohol intoxication-related genes by function. These genes expression may be potential targets for treatment or drug screening for acute alcohol intoxication.
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Concentração de Íons de HidrogênioRESUMO
As one of the most serious types of psoriasis, pathogenesis of erythrodermic psoriasis (EP) is unclear so far. In this study, we aimed to detect the levels of Th1/Th2 cytokine-associated transcription factors and T-lymphocyte clone in peripheral blood mononuclear cells (PBMCs) derived from EP patients, and gene expression level of T-bet/GATA-3 in skin lesion. The potential role of Th1/Th2 reaction pattern played in the pathogenesis of EP was also discussed. Serum levels of IFN-γ, IL-2, IL-4 and IL-10 were quantified by ELISA among 16 EP patients, 20 psoriasis vulgaris (PV) patients and 15 healthy controls. The expression levels of T-bet/GATA-3 in the skin lesion and PBMCs were examined by real-time qPCR. The ratio of Th1/Th2 was measured by flow cytometry. The levels of IFN-γ, IL-2, IL-4 and IL-10 were higher in EP patients than in the healthy controls. The levels of IL-4 and IL-10 were 69.44±11.45 and 12.62±4.57 pg/mL, respectively, in EP patients, significantly higher than those in PV patients and healthy controls (P<0.05). Flow cytometry revealed the levels of both Th1 and Th2 in PBMCs from EP patients were higher than those in healthy controls, and the Th1/Th2 ratio was dramatically lower than in PV patients (P<0.01). The ratios of IFN-γ/IL-4 and T-bet/GATA-3 in EP patients were both less than 1.0, suggesting a reversal when compared with the other two groups. Our study indicated that the EP patients exerted a Th1/Th2 bidirectional response pattern, and the balance of Th cell subsets inclines to Th2, which might be one of the important mechanisms of EP pathogenesis.
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Dermatite Esfoliativa/imunologia , Psoríase/imunologia , Pele/imunologia , Células Th1/imunologia , Células Th2/imunologia , Adulto , Citocinas/imunologia , Dermatite Esfoliativa/patologia , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Masculino , Psoríase/patologia , Pele/patologia , Células Th1/patologia , Células Th2/patologiaRESUMO
Efficient control over several possible reaction pathways of free radicals is the chemical basis of their highly selective transformations. Among various competing reaction pathways, sulfonimidyl radicals generated from the electrolysis of 2-alkynylbenzenesulfonamides undergo cascade migratory or ortho-cyclization cyclization selectively. It is found that the incorporation of an extra 2-methyl substituent biases the selective migration of the acyl- over vinyl-linker of the key spirocyclic cation intermediate and thus serves as an enabling handle to achieve the synthetically interesting yet under-investigated cascade migratory cyclization of spirocyclic cations.
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The preparation of polycyclic aromatic hydrocarbons (PAHs) by the Scholl reaction is typically performed by using superstoichiometric oxidants. Herein, we develop an electrochemical continuous-flow Scholl reaction to access PAHs that features a reduction in the use of supporting electrolytes and easy scale-up without changing the reaction conditions and setups. This reaction allows the synthesis of distorted PAHs containing three [5]helicene units that possess intriguing electronic and optical properties.
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OBJECTIVE: To determine the role of IGF-1/PI3K pathway and investigate the molecular mechanism of Fuzhenghuayu (FZHY) therapy in a spontaneous recovery rat model of liver fibrosis. METHODS: The liver fibrosis model was induced in male Wistar rats by administering 8 weeks of twice weekly CCL4 intraperitoneal injections without (untreated model) or with once daily FZHY (treated model). Normal, untreated rats served as the control group. At weeks 4, 6 and 8 (fibrosis) and 10, 12 and 14 (spontaneous recovery) after modeling initiation, effects on protein (a-SMA, IGF-1, PI3K) and mRNA (IGF-1, PI3K) expression levels were evaluated by immunohistochemistry and RT-PCR, respectively. Serum markers of liver function (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)) and liver cell damage (alkaline hydrolysis, HYP) were measured. Histology was performed to assess the degree of inflammation and fibrosis (Ishak scoring system). RESULTS: In the untreated model group, progression of liver fibrosis (weeks 4, 6 and 8) was accompanied by gradual increases in inflammation, necrosis, serum ALT and AST, and hepatic expression of a-SMA protein and IGF-1 and PI3K protein and mRNA; however, during the spontaneous recovery period (weeks 10, 12 and 14) the IGF-1 and PI3K protein and mRNA levels rapidly decreased and the HYP level, Ishak score, and a-SMA hepatic expression also decreased. The FZHY-treated model group showed significantly lower fibrosis-related up-regulation of IGF-1 and PI3K protein and mRNA expression, HYP level, Ishak score, and a-SMA hepatic expression at each time point (vs. untreated model group). CONCLUSION: The IGF-1/PI3K pathway may contribute to progression of liver fibrosis. The mechanism by which FZHY prevents liver fibrosis in a rat model may involve blocking of the IGF/PI3K pathway and inhibiting HSC activation.
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Medicamentos de Ervas Chinesas/farmacologia , Cirrose Hepática Experimental/metabolismo , Fígado/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Fator de Crescimento Insulin-Like I/metabolismo , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/patologia , Masculino , Fosfatidilinositol 3-Quinases/metabolismo , Ratos , Ratos WistarRESUMO
Electrochemical dearomative spirocyclization serves as a green and sustainable approach to convert the flat, two-dimension aromatic feedstock into the value-added three-dimension spirocyclic architectures. This review highlights the recent advances, emphasizes mechanistic discussions, and showcases synthetic applications of this emerging versatile and powerful transformation.
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OBJECTIVE: To study the toll-like receptor 2 (TLR2) Arg753Gln gene polymorphisms of acne patients of Gan-depression induced qi stagnation syndrome and damp-heat in the interior syndrome, thus laying the foundation for genetics studies on its occurrence. METHODS: The distribution and the frequency of allelic genes were studied in 75 acne patients of damp-heat in the interior syndrome, and 87 acne patients with Gan-depression induced qi stagnation syndrome, as well as 70 healthy subjects (as the normal control group) using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. RESULTS: There was significant difference in the frequency of the genotype Arg/Gln + Gln/Gln in the TLR2 Arg753Gln genetic polymorphisms [26. 44% (23/87) in Gan-depression induced qi stagnation syndrome, 41.33% (31/75) in damp-heat in the interior syndrome, and 12.86% (9/70) in the normal control group] (P < 0.05). CONCLUSION: The existence of 753Gln allele in the Arg753Gln of TLR2 increased the onset risk of acne patients of Gan-depression induced qi stagnation syndrome and damp-heat in the interior syndrome.
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Acne Vulgar/genética , Polimorfismo Genético , Receptor 2 Toll-Like/genética , Acne Vulgar/diagnóstico , Acne Vulgar/etnologia , Adolescente , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Medicina Tradicional Chinesa , Fenótipo , Qi , Adulto JovemRESUMO
The Friedel-Crafts type alkylation of C2-tethered thiophenes has been reported to be nonregioselective. Taking advantage of the highly regioselective 5-exo-trig spirocyclization of an electrochemically generated amidyl radical, we have unraveled an electrochemical dearomative spirocyclization of N-acyl thiophene-2-sulfonamides. Various nucleophilic agents, including carboxylates, alcohols, and fluoride, are readily incorporated to afford the remotely functionalized spirocyclic dihydrothiophenes, and their novel spirocyclic scaffolds have been shown to exhibit promising antitumor activities.
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Sulfonamidas , Tiofenos , Álcoois , Alquilação , EstereoisomerismoRESUMO
In order to study the comprehensive effects of different types of dehydrating agents on the dewatering and solidification of dredged sediments, this study took the dredged sediments of Taihu Lake as the research object and selected microorganisms, polymeric iron aluminum salts, organic polymers, organic-inorganic composites, and aluminum salt microorganisms. These five types of composite dehydrating agents were used to conduct a three-month solidification test on the dredged sediment by means of geotechnical pipe bag solidification. The results of the study showed that the dehydration efficiency of organic polymers and organic-inorganic composite chemicals was better. After one month, the water content of sediment dropped to 61.78% and 63.26%, respectively, which then dropped to 40.56% and 32.16% after three months. Compared with that of the unsolidified sludge, the total nitrogen of the bottom sludge after solidification by the organic-inorganic composite agent was reduced by 74.82%, reaching 591 mg·kg-1, primarily due to the reduction in ammonia nitrogen. The solid sludge contained mainly aluminum-bound phosphorus, calcium-bound phosphorus, and iron-bound phosphorus. Among them, four groups (organic-inorganic composite) had the largest reduction in active phosphorus, with the lowest being 64.3 mg·kg-1. In addition, organic polymer agents had the best curing effect on heavy metals, the comprehensive ecological risk index of heavy metals was reduced by 51.3%, and the leaching toxicity concentration was far below the standard threshold. This study showed that organic polymers and organic-inorganic composite medicaments have a better effect on the dehydration and solidification of bottom sludge and thus have good application prospects.
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Metais Pesados , Poluentes Químicos da Água , Alumínio , Desidratação , Monitoramento Ambiental , Sedimentos Geológicos/química , Humanos , Ferro , Metais Pesados/análise , Nitrogênio/análise , Compostos Orgânicos , Fósforo/análise , Polímeros , Esgotos , Poluentes Químicos da Água/análiseRESUMO
OBJECTIVE: Contrast-enhanced ultrasound (CEUS) is advantageous for evaluating microcirculation, and has been applied to assess arthritis in previous studies. However, CEUS examinations have not been studied for hemophilia arthritis. Hemophilia arthritis is different from other arthritis, because it is induced by spontaneous joint bleeding. Hence, CEUS may have special value in evaluating hemophilia arthritis. The present study assessed the value of CEUS in evaluating synovial hypertrophy and predicting recurrent joint bleeding in severe hemophilia A patients. METHODS: From August 2016 to January 2017, 81 severe hemophilia A patients, who were referred to our hospital for ultrasound joint assessment with conventional ultrasound, were enrolled. Among these 81 patients, 46 patients consented for CEUS examinations on the same day. RESULTS: Compared to color Doppler flow imaging (CDFI), four more joints presented with a blood flow signal under CEUS mode. In addition, the synovial hypertrophy measured by CEUS was thicker than that measured by conventional ultrasound. The ultrasound scores (including the total grey-scale ultrasound score, joint effusion/hemarthrosis, synovial hypertrophy, CDFI semi-quantitative score, and CEUS semi-quantitative score) were significantly higher in the joint bleeding group than in the no joint bleeding group (P<0.05). Furthermore, these ultrasound scores were positively correlated with the joint bleeding frequency, and had the highest correlation with the CEUS score (r=0.620, P<0.05). CONCLUSION: CEUS can more accurately assess the degree of synovial hypertrophy and vascularization, and diagnose synovitis, when compared to conventional ultrasound. In addition, CEUS appears to be essential for evaluating the possibility of recurrent joint bleeding, and providing more reliable evidence for individualized treatment.
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Artrite , Hemofilia A , Sinovite , Artrite/complicações , Artrite/diagnóstico por imagem , Hemartrose/diagnóstico por imagem , Hemartrose/etiologia , Hemofilia A/complicações , Hemofilia A/diagnóstico por imagem , Hemorragia/etiologia , Humanos , Sinovite/complicações , Sinovite/diagnóstico por imagem , Ultrassonografia/métodosRESUMO
Oxidative stress is one of the most important causes of the cellular senescence process. Previous studies showed that ß-catenin can regulate FoxO3a and this association was enhanced in cells exposed to oxidative stress. It has also been reported that ß-catenin can regulate some senescence-related proteins. We propose that ß-catenin may play a crucial role in senescence of normal human primary skin fibroblasts (NHSFs). Here, we explored the roles and mechanisms of ß-catenin on H(2)O(2)-induced senescence in NHSFs. ß-catenin expression was decreased in NHSFs after H(2)O(2) treatment. Overexpression of ß-catenin in NHSFs led to a marked delay of many senescent phenotypes induced by H(2)O(2). Furthermore, overexpression of ß-catenin in NHSFs can antagonise the alteration of reactive oxygen species accumulation and some senescence-related proteins expression induced by H(2)O(2) treatment. Our data demonstrated that ß-catenin can protect NHSFs from H(2)O(2)-induced premature senescence by alleviating oxidative stress and regulating some senescence-related molecules.
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Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Peróxido de Hidrogênio/toxicidade , Pele/efeitos dos fármacos , Pele/metabolismo , beta Catenina/metabolismo , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Estresse Oxidativo , Pele/patologia , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/patologiaRESUMO
BACKGROUND: Inflammatory cytokines such as tumor necrosis factor receptor 2 (TNFR2) and Toll-like receptor 2 (TLR2) are the main responsible mediators of inflammatory acne. Factors affecting their production may possibly influence the degree of inflammatory response and hence may account for the clinical severity of acne. However, the roles of TNFR2 and TLR2 in the pathophysiology of acne vulgaris are poorly understood. We therefore investigated the relationship between acne vulgaris susceptibility and the polymorphisms in the TNFR2 M196R as well as TLR2 Arg753Gln gene. METHODS: A total of 93 acne vulgaris patients and 90 healthy subjects from the Chinese Han ethnic group were enrolled in the study. The polymerase chain reaction restriction fragment length polymorphism technique was adopted to analyze the single-nucleotide polymorphisms of the TNFR2 M196R and TLR2 Arg753Gln gene, and to examine the association between acne vulgaris and the polymorphisms in the TNFR2 M196R as well as TLR2 Arg753Gln gene. The relationship between different genotypes and the susceptibility to acne vulgaris was analyzed. RESULTS: There is a significant difference in the frequency of TNFR2 M196R genetic polymorphisms between the moderate-acne to severe-acne subgroups and the control group (p < 0.05), and there is also a significant difference in the frequency of TLR2 Arg753Gln genetic polymorphisms between the severe-acne subgroup and control group (p < 0.05). CONCLUSION: The 196R allele of TNFR2 M196R as well as the 753Gln allele of TLR2 Arg753Gln are risk factors for acne vulgaris in Chinese Han patients, further supporting the contribution of inflammatory cytokines to the pathogenesis of acne.
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Acne Vulgar/genética , Polimorfismo de Nucleotídeo Único , Receptores Tipo II do Fator de Necrose Tumoral/genética , Receptor 2 Toll-Like/genética , Acne Vulgar/fisiopatologia , Distribuição de Qui-Quadrado , China , Citocinas/fisiologia , Etnicidade/genética , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Índice de Gravidade de DoençaRESUMO
Procalcitonin (PCT) is widely used to diagnose a bacterial infection. An increased serum PCT can also be observed in tumors. We presented an unusual case of a metastatic PNET producing and secreting PCT. Immunohistochemistry was used to demonstrate that PCT can be secreted by PanNET.
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BACKGROUND: Urinary tract infection (UTI) is the most common kind of infection in the early stage after kidney transplantation. Although many studies have investigated the risk factors for UTI following kidney transplantation, few studies have focused on the risk factors for UTI in the early stage after transplantation. METHODS: The early-stage data of patients who underwent kidney transplantation between January 2018 and December 2019 in a first-class tertiary hospital in Suzhou, China, were retrospectively analyzed. The general and UTI information of the recipients was subjected to univariate analysis. Variables with statistical significance in the univariate analysis were included in a multivariate logistic regression model. RESULTS: A total of 129 recipients were recruited, among whom 62 patients had a UTI in the early stage after kidney transplantation (48.1%), and the median (interquartile range) of onset time was 5 (4, 10) days after the surgery. A total of 324 strains of UTI pathogens were detected in the 62 recipients after kidney transplantation, 279 of which were gram-negative bacilli (86.1%). Multivariate logistic regression analysis showed that female sex and delayed graft function (DGF) were independent risk factors for early-stage UTI, with odds ratios of 0.095 and 3.753, respectively. CONCLUSIONS: The incidence of early UTI after kidney transplantation is high. Females and DGF patients are more prone to UTIs. Comprehensive prevention and treatment measures should be taken as early as possible against the risk factors to reduce the incidence of UTI.
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BACKGROUND: In China, the incidence of benign prostatic hyperplasia (BPH) is rising with the average lifespan of men. Transurethral resection of the prostate (TURP) is recognized as the gold standard for surgical treatment of BPH. Continuous bladder irrigation (CBI) is often required after operation. The irrigation rate is often manually adjusted based on the color of the drainage fluid, but it is difficult to know how much to adjust it based on color. To better adjust the irrigation rate and reduce related complications, we developed and evaluated a post-TURP CBI rate adjustment card. METHODS: A total of 103 BPH patients who underwent post-TURP CBI at our hospital between April and July 2020 were enrolled in this study and were assigned to the control group (n=49) or the experimental group (n=54) according to the different hospital areas. In the control group, the CBI rate was adjusted based on the clinical evaluation of the color of the drainage fluid; in the experimental group, the CBI rate was adjusted based on the color of drainage fluid evaluated with our homemade post-TURP CBI rate adjustment card. RESULTS: The incidence of bladder spasm, the incidence of clot-related catheter blockage, the volume of irrigation solution used, and the irrigation time were significantly lower or shorter in the experimental group than in the control group. The patient satisfaction score was significantly higher in the experimental group (P<0.05). CONCLUSIONS: For BPH patients receiving post-TURP CBI, the homemade post-TURP CBI rate adjustment card can provide objective data for clinical care, reduce postoperative complications, and improve patient satisfaction. Therefore, it should be more widely used in clinical practice.