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1.
J Org Chem ; 88(20): 14659-14669, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37787482

RESUMO

An efficient palladium-catalyzed intermolecular selective C-H silylation of boronic acids is described. The combination of palladium catalyst with copper oxidant enables ortho-selective C-H silylation by employing hexamethyldisilane as the trimethylsilyl source, which relies on the control of NBE derivatives as a switch, thus providing straightforward access to divergent organosilicon compounds.

2.
Org Biomol Chem ; 21(8): 1662-1666, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36734361

RESUMO

As an efficient and green synthesis method, the electrocatalysis hydrogen evolution coupling reaction has been widely used by chemists to realize the combining of two nucleophiles. In this work, an alternative method to synthesize 6-phosphorylated phenanthridines has been developed by synergistically utilizing electrocatalysis and Mn catalysis, with moderate to relatively good yields achieved. Mild and oxidant-free conditions make this synthetic method applicable in various settings.

3.
Phys Chem Chem Phys ; 25(27): 18454-18464, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37401748

RESUMO

The health hazards caused by low concentrations of Pb2+ ions in drinking water systems are of significant concern. In order to remove Pb2+ ions and retain Na+, K+, Ca2+ and Mg2+ as harmless competitive ions without simultaneous removal, nickel foam (NF)/Mn2CoO4@tannic acid (TA)-Fe3+ electrodes were prepared by a hydrothermal method and a coating method and an asymmetric capacitive deionization (CDI) system is established using the prepared electrodes and a graphite paper positive electrode. The designed asymmetric CDI system exhibited a high Pb2+ adsorption capacity of 375 mg g-1 with high removal efficiency and significant regeneration behavior at 1.4 V at neutral pH. When the asymmetric CDI system is used to enrich a hydrous solution of mixed Na+, K+, Ca2+, Mg2+ and Pb2+ ions each with a concentration of 10 ppm and 100 ppm by electrosorption at a 1.4 V operating voltage, the removal rate of Pb2+ is as high as 100% and 70.8% respectively, and the relative selectivity coefficients are 4.51-43.22. According to the different adsorption mechanisms of lead ions and coexisting ions, the separation and recovery of ions can be realized by a two-step desorption process, thereby providing a new method for removing Pb2+ ions from drinking water with excellent application potential.

4.
Plant Cell ; 31(1): 172-188, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30610168

RESUMO

To defend against pathogens, plants have developed complex immune systems, including plasma membrane receptors that recognize pathogen-associated molecular patterns, such as chitin from fungal cell walls, and mount a defense response. Here, we identify a chitinase, MoChia1 (Magnaporthe oryzae chitinase 1), secreted by M. oryzae, a fungal pathogen of rice (Oryza sativa). MoChia1 can trigger plant defense responses, and expression of MoChia1 under an inducible promoter in rice enhances its resistance to M. oryzae MoChia1 is a functional chitinase required for M. oryzae growth and development; knocking out MoChia1 significantly reduced the virulence of the fungus, and we found that MoChia1 binds chitin to suppress the chitin-triggered plant immune response. However, the rice tetratricopeptide repeat protein OsTPR1 interacts with MoChia1 in the rice apoplast. OsTPR1 competitively binds MoChia1, thereby allowing the accumulation of free chitin and re-establishing the immune response. Overexpressing OsTPR1 in rice plants resulted in elevated levels of reactive oxygen species during M. oryzae infection. Our data demonstrate that rice plants not only recognize MoChia1, but also use OsTPR to counteract the function of this fungal chitinase and regain immunity.


Assuntos
Magnaporthe/patogenicidade , Oryza/metabolismo , Quitinases/genética , Quitinases/metabolismo , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno , Imunidade Vegetal/genética , Imunidade Vegetal/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
BMC Health Serv Res ; 22(1): 417, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35351121

RESUMO

BACKGROUND: A nationwide campaign for rational proton pump inhibitor (PPI) use launched in 2015 had a positive impact for hospitalized patients PPI use. But there were few studies focusing on the rational use of PPIs in outpatients. In 2018, the PPI management committee conducted a year-long intervention on the appropriate use of PPIs in outpatient and emergency departments, including clinical pharmacist interventions and stewardship interventions. The purpose of this study was to examine the impact of the PPI management committee's multifaceted interventions by comparing the real-world acid suppressant prescribing patterns for outpatients before (2017) and after intervention (2019) at a Chinese tertiary teaching hospital. METHODS: Prescriptions containing any acid suppressant in outpatient and emergency departments in baseline (2017) and postintervention (2019) periods were extracted from the hospital information system and the prescription automatic screening system. Acid suppressant prescribing patterns were evaluated based on primary diagnoses and patient demographics. The prescribed acid suppressants stratified using age groups (< 7, 7-17, 18-45, 46-65, 66-85 and > 85 years) were also examined. RESULT: The utilization rate of acid suppressant in 2017 and 2019 was 2.5% (41,165/1,619,366) and 2.2% (49,550/2,236,471), respectively (P < 0.0001). 60,135 acid suppressant prescriptions were obtained in 2017 and 73,275 in 2019. The rate of acid suppressant prescriptions for the approved indications significantly increased from 62.6% (2017) to 65.4% (2019) (P < 0.0001). Prescriptions diagnosed as abnormal symptoms, signs and clinical manifestations, decreased in 2019 (13.0% vs. 16.5%, P < 0.0001). The most frequently prescribed PPIs differed between 2017 and 2019 (rabeprazole 2017 vs. esomeprazole 2019). Omeprazole was the most common PPI and cimetidine was the most common H2RA prescribed to patients aged < 18 years in 2017 and 2019. A total of CNY11.83 million was spent on acid suppressants in 2019, accounting for about 48.7% of total medication cost, increased by 11.3% from 2017 (37.4%). CONCLUSION: The proportion of acid suppressant prescriptions for approved indications was enhanced after the PPI management committee's multifaceted interventions, but there were still some problems in the selection of acid suppressants.


Assuntos
Pacientes Ambulatoriais , Inibidores da Bomba de Prótons , Adolescente , Idoso de 80 Anos ou mais , Serviço Hospitalar de Emergência , Humanos , Omeprazol/uso terapêutico , Farmacêuticos , Inibidores da Bomba de Prótons/uso terapêutico
6.
Anal Chem ; 93(32): 11298-11304, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34369142

RESUMO

Small extracellular vesicles (sEVs), often referred to as exosomes, are potential biomarkers for noninvasive cancer diagnosis. However, because of their phenotype heterogeneity, precise detection of tumor-derived sEVs is a great challenge. Herein, a dual-aptamer-assisted AND logic gate was fabricated for sensitive electrochemical detection of tumor-derived sEVs based on a cyclic enzymatic signal amplification strategy. Four different tumor-derived sEVs were used to verify the feasibility of the AND logic gate, and CCRF-CEM sEVs were successfully detected by this assay. The electrochemical assay shows a good linear response from 4 × 103 to 8 × 107 particles/µL, with a detection limit of 920 particles/µL, for CCRF-CEM sEVs, indicating potential application in accurate cancer diagnostics.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Exossomos , Vesículas Extracelulares , Neoplasias , Humanos , Neoplasias/diagnóstico
7.
Anal Chem ; 92(7): 5302-5310, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32148013

RESUMO

MicroRNAs (miRNAs) in cancer cell-derived exosomes are important cancer biomarkers. Herein, a sensitive hybridization chain reaction (HCR) electrochemical assay was fabricated for the detection of exosomal microRNA-122 (miR-122). The hairpin DNA (hpDNA) probes were first immobilized on the surface of a gold electrode. In the presence of miR-122, the hairpin structure of the hpDNA could be opened and triggered the HCR through the cross-opening and hybridization of two helper DNA hairpins. Long nicked double helixes generated from HCR are used to capture more RuHex and increase the signal of differential pulse voltammetry (DPV). In this assay, the density of the hpDNA probes on the surface of the gold electrode was precisely controlled by the simultaneous immobilization of hpDNA and short 12 nucleotides single-stranded DNA (S-12), providing a very high amplification efficiency. More importantly, the false positive signal could be reduced or completely eliminated by applying exonuclease I (Exo I) before the introduction of target miR-122. Under optimal conditions, the assay offers very high sensitivity with an attomolar level detection limit, a linear range with 9 orders of magnitude, and specificity in single mismatch discrimination. This sensitive electrochemical assay could successfully evaluate the miR-122 concentration in different cancer-derived exosomes, indicating its potential use in cancer diagnostics.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Exossomos/química , MicroRNAs/análise , Hibridização de Ácido Nucleico , Reações Falso-Positivas , Células Hep G2 , Humanos , Células MCF-7 , MicroRNAs/genética , Células Tumorais Cultivadas
8.
Nanotechnology ; 31(38): 385703, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32464605

RESUMO

Graphene that consists of less than 10 layers is expensive; moreover, it tends to agglomerate. These disadvantages restrict its utility. In this regard, the present study aimed to reduce the number of layers of a functionalized graphene (FG) with 10-30 layers to less than 10 layers by using an ultrasonic processor. We prepared nanocomposite films of polyvinyl alcohol (PVA) incorporated with FG by a simple hydrothermal method and ultrasonic dispersion. Oxygen transmission rate and water vapor permeability were considerably increased on account of modifying PVA with FG. Furthermore, the mechanical properties, thermostability, and barrier properties were improved. The barrier efficiency of the nanocomposites at different temperatures remained high for long periods of operation because of the network bonding. A simple procedure involving relatively low-cost nanomaterials could unlock the potential of nanocomposite FG/PVA films in the fields of coating, packaging, and semiconductor materials.

9.
J Org Chem ; 84(11): 7449-7458, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31083904

RESUMO

A highly efficient and practical synthesis of benzofulvenes was developed via ketone-directed Cp*Co(III)-catalyzed sequential C-H activation, addition, cyclization, and dehydration cascade processes between simple aromatic ketones and alkynes. The reaction tolerates a variety of functional groups, and various benzofulvenes were efficiently synthesized in 42-92% yields.

10.
J Org Chem ; 84(17): 11195-11202, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31407909

RESUMO

A novel and efficient synthesis of sulfones was developed via a silver-promoted decarboxylative sulfonylation reaction between aromatic carboxylic acids and sodium sulfinates for the first time. The approach features operational simplicity and good functional group compatibility and uses readily available starting materials. Furthermore, mechanistic studies reveal that the decarboxylative sulfonylation reaction is likely to proceed via a radical mechanism.

11.
Med Sci Monit ; 25: 7306-7311, 2019 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-31563919

RESUMO

BACKGROUND The ultrasonography-guided technique is superior to the traditional palpation technique for artery cannulation. However, considering the complexity of assembling the ultrasonography machine, this technique has not been extensively used. Here, we compared the ultrasonography-guided technique with the traditional palpation technique in adult patients in the pre-anesthesia room. MATERIAL AND METHODS A total of 66 patients were enrolled and divided into 2 groups: the ultrasonography group and the palpation group. Anesthesiologists then cannulated the radial artery via either method. The primary outcomes included the first-attempt success and total success rates, as well as the cannulation duration and total procedure duration. The secondary outcome was the rate of complications attributable to cannulation. RESULTS Overall, 60 patients were analyzed in the present study. The first-attempt success rate in the ultrasonography group (96.6%) was significantly higher than that in the palpation group (73.3%; P=0.03). There was no significant difference in the cannulation duration and the total procedure duration between the 2 groups. The rate of complications caused by cannulation in 2 groups was similar. CONCLUSIONS The ultrasonography-guided radial artery cannulation technique is more efficient for arterial cannulation in the pre-anesthesia room compared with the traditional palpation method.


Assuntos
Cateterismo/métodos , Palpação/métodos , Artéria Radial/diagnóstico por imagem , Adulto , Anestesia , Artérias/diagnóstico por imagem , Cateterismo Periférico/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ultrassonografia/métodos , Ultrassonografia de Intervenção
12.
Plant J ; 89(2): 338-353, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27701783

RESUMO

Ethylene plays diverse roles in plant growth, development and stress responses. However, the roles of ethylene signaling in immune responses remain largely unknown. In this study, we showed that the blast fungus Magnaporthe oryzae infection activated ethylene biosynthesis in rice. Resistant rice cultivars accumulated higher levels of ethylene than susceptible ones. Ethylene signaling components OsEIN2 and the downstream transcription factor OsEIL1 positively regulated disease resistance. Mutation of OsEIN2 led to enhanced disease susceptibility. Whole-genome transcription analysis revealed that responsive genes of ethylene, jasmonates (JAs) and reactive oxygen species (ROS) signaling as well as phytoalexin biosynthesis genes were remarkably induced. Transcription of OsrbohA/B, which encode NADPH oxidases, and OsOPRs, the JA biosynthesis genes, were induced by M. oryzae infection. Furthermore, we demonstrated that OsEIL1 binds to the promoters of OsrbohA/OsrbohB and OsOPR4 to activate their expression. These data suggest that OsEIN2-mediated OsrbohA/OsrbohB and OsOPR transcription may play essential roles in ROS generation, JA biosynthesis and the subsequent phytoalexin accumulation. Therefore, the involvement of ethylene signaling in disease resistance is probably by activation of ROS and phytoalexin production in rice during M. oryzae infection.


Assuntos
Etilenos/metabolismo , Oryza/metabolismo , Oryza/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/metabolismo , Resistência à Doença/fisiologia , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Magnaporthe/patogenicidade , Mutação , Oryza/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Transdução de Sinais , Fitoalexinas
13.
J Org Chem ; 83(15): 8556-8566, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-29923724

RESUMO

An efficient protocol for the synthesis of internal aryl alkynes was achieved via Cu-catalyzed decarboxylative cross-coupling reactions, and to the best of our knowledge, this is the first example of a Cu-catalyzed decarboxylative alkynylation of benzoic acids with terminal alkynes. This approach utilizes simple Cu salt as catalyst and O2, an abundant, clean, and green material, as the oxidant. The reaction tolerates various functional groups, and a variety of internal aryl alkynes were synthesized in 46-83% yields.

14.
Org Biomol Chem ; 15(27): 5674-5679, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28654110

RESUMO

A novel copper-catalyzed decarboxylative methylthiolation of arenecarboxylate salts has been realized using DMSO as the methylthiolation source. Various potassium aryl carboxylates underwent decarboxylative methylthiolation under air to furnish the corresponding aryl methyl thioethers in moderate to excellent yields. The reaction tolerated a wide variety of functional groups. Notably, the synthesis of ethylthioethers was also successfully achieved directly from diethyl sulfoxide under similar reaction conditions.

15.
PLoS One ; 19(6): e0306055, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38913683

RESUMO

Agricultural socialized service is gradually emerging as a new stimulus for enhancing the agricultural production environment. However, their precise impact on improving the agricultural ecological environment and promoting the green development of agriculture remains incompletely understood. Therefore, leveraging panel data spanning from 2003 to 2020 across 31 provinces in China, this study utilizes the bidirectional fixed effect model, moderating effect model, and spatial Durbin model to systematically assess the influence of agricultural socialized services on agricultural green development and its spatial ramifications. The findings show that (I) agricultural socialized services significantly contribute to promoting agricultural green development, particularly in regions with lower aging demographics. (II) The application of the spatial Durbin model reveals that this promotional effect does not exhibit significant spatial spillover effect. (III) The role of agricultural socialized services in fostering agricultural green development can be significantly enhanced by advancements in land transfer, agricultural technological innovations, and the improvement of rural human capital. In conclusion, the study provides a set of policy recommendations that include government financial support, facilitating land transfer, improving rural education and technical training, and promoting green production technologies to effectively promote agricultural green development.


Assuntos
Agricultura , Agricultura/métodos , Humanos , China , População Rural , Conservação dos Recursos Naturais
16.
Chem Asian J ; 19(4): e202301040, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38019114

RESUMO

A palladium-catalyzed reaction for intermolecular selective C-H cyclocarbonylation of 2-iodobiphenyls is described. Intriguingly, the vinylene carbonate acts as a carbon monoxide transfer agent to enable the annulation reaction. Moreover, as a versatile synthon, fluoren-9-one can be transformed into a variety of functionalized organic molecules, such as [1,1'-biphenyl]-2-carboxylic acid, 1'H,3'H-spiro[fluorene-9,2'-perimidine] and N-tosylhydrazones.

17.
Org Lett ; 26(26): 5506-5510, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38900141

RESUMO

A palladium(II)-catalyzed norbornene-mediated remote selective meta-C-H silylation of primary benzamides was developed for the synthesis of arylsilanes. Such a conversion provides access to a range of arylsilanes with exclusive selectivity using norbornene (NBE) as the meta-C-H activator. The amide directing group can be detached simultaneously through C-C bond cleavage or undergo a dehydration reaction pathway to form nitriles.

18.
Polymers (Basel) ; 16(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38674991

RESUMO

To enhance the various properties of polyvinyl alcohol (PVA), varying concentrations of carboxy-functionalized graphene (CFG) were employed in the preparation of CFG/PVA nanocomposite films. FTIR and XRD analyses revealed that CFG, in contrast to graphene, not only possesses carboxylic acid group but also exhibits higher crystallinity. Mechanical testing indicated a notable superiority of CFG addition over graphene, with optimal mechanical properties such as tensile and yield strengths being achieved at a 3% CFG concentration. Relative to pure PVA, the tensile strength and yield strength of the composite increased by 2.07 and 2.01 times, respectively. XRD analysis showed distinct changes in the crystalline structure of PVA with the addition of CFG, highlighting the influence of CFG on the composite structure. FTIR and XPS analyses confirmed the formation of ester bonds between CFG and PVA, enhancing the overall performance of the material. TGA results also demonstrated that the presence of CFG enhanced the thermal stability of CFG/PVA nanocomposite films. However, analyses using scanning electron microscopy and transmission electron microscopy revealed that a 3% concentration of CFG was uniformly dispersed, whereas a 6% concentration of CFG caused aggregation of the nanofiller, leading to a decrease in performance. The incorporation of CFG significantly enhanced the water vapor and oxygen barrier properties of PVA, with the best performance observed at a 3% CFG concentration. Beyond this concentration, barrier properties were diminished owing to CFG aggregation. The study further demonstrated an increase in electrical conductivity and hydrophobicity of the nanocomposites with the addition of CFG. Antibacterial tests against E. coli showed that CFG/PVA nanocomposites exhibited excellent antibacterial properties, especially at higher CFG concentrations. These findings indicate that CFG/PVA nanocomposites, with an optimized CFG concentration, have significant potential for applications requiring enhanced mechanical strength, barrier properties, and antibacterial capabilities.

19.
Org Lett ; 26(6): 1143-1147, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38299994

RESUMO

A palladium/norbornene (NBE)-catalyzed regioselective C-H silylation of free NH-indoles is reported. This protocol uses Pd(OAc)2 as the catalyst and Cu(OAc)2 as the oxidant, and the reaction relies on the control of NBE as a switch. The reaction tolerates various functional groups, and a series of silicon-containing indoles were directly synthesized in 30%-94% yields.

20.
Sci Rep ; 13(1): 8111, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208381

RESUMO

In order to assess the effectiveness of the Special Antimicrobial Stewardship Campaign launched by Ministry of Health of China in 2011, this study focused on the effectiveness and trends in the clinical use of antimicrobial drugs in selected hospitals in Southern Sichuan, China. This study collected and analyzed antibiotic data from 9 hospitals in Southern Sichuanin 2010, 2015, and 2020, including the rate of antibiotic use, expense, the intensity of antibiotic use and antibiotic use during the type I incisions of perioperative period. After 10 years of continuous improvement, the utilization rate of antibiotics in outpatients of the 9 hospitals continued to decline and was controlled below 20% by 2020, while the utilization rate in inpatients also significantly decreased, most were controlled within 60%. The use intensity of antibiotics (DDD (defined daily doses) per 100 bed-days) decreased from an average of 79.95 in 2010 to 37.96 in 2020. The prophylactic use of antibiotics decreased significantly in type I incision. The proportion of use within 30 min-1 h before operation was significantly increased. After the special rectification and sustained development of the clinical application of antibiotics, the relevant indicators of antibiotics tend to be stable, indicating that this Administration of antimicrobial drugs is conducive to improving the level of rational clinical application of antibiotics.


Assuntos
Gestão de Antimicrobianos , Ferida Cirúrgica , Humanos , Antibacterianos/uso terapêutico , Uso de Medicamentos , Hospitais , China , Ferida Cirúrgica/tratamento farmacológico
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