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1.
Environ Sci Technol ; 58(24): 10515-10523, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38622088

RESUMO

Hydrogen sulfide (H2S), a toxic gas abundant in natural gas fields and refineries, is currently being removed mainly via the Claus process. However, the emission of sulfur-containing pollutants is hard to be prevented and the hydrogen element is combined to water. Herein, we report an electron-mediated off-field electrocatalysis approach (OFEC) for complete splitting of H2S into H2 and S under ambient conditions. Fe(III)/Fe(II) and V(II)/V(III) redox mediators are used to fulfill the cycles for H2S oxidation and H2 production, respectively. Fe(III) effectively removes H2S with almost 100% conversion during its oxidation process. The H+ ions are reduced by V(II) on a nonprecious metal catalyst, tungsten carbide. The mediators are regenerated in an electrolyzer at a cell voltage of 1.05 V, close to the theoretical potential difference (1.02 V) between Fe(III)/Fe(II) and V(II)/V(III). In a laboratory bench-scale plant, the energy consumption for the production of H2 from H2S is estimated to be 2.8 kWh Nm-3 H2 using Fe(III)/Fe(II) and V(II)/V(III) mediators and further reduced to about 0.5 kWh Nm-3 H2 when employing well-designed heteropolyacid/quinone mediators. OFEC presents a cost-effective approach for the simultaneous production of H2 and elemental sulfur from H2S, along with the complete removal of H2S from industrial processes. It also provides a practical platform for electrochemical reactions involving solid precipitation and organic synthesis.


Assuntos
Sulfeto de Hidrogênio , Hidrogênio , Enxofre , Sulfeto de Hidrogênio/química , Hidrogênio/química , Catálise , Enxofre/química , Oxirredução , Eletroquímica , Técnicas Eletroquímicas
2.
J Insect Sci ; 23(4)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37471132

RESUMO

The response of Spodoptera frugiperda genes toward insecticides is crucial for guiding insecticide use. The regulation of the S. frugiperda genes via long noncoding RNAs (lncRNAs) under insecticide treatment should be investigated. In this study, 452 differentially expressed lncRNAs were identified by analyzing RNA-sequencing data of S. frugiperda under 23 pesticide treatments. We found 59 and 43 differentially expressed lncRNAs that could regulate detoxification-related cytochrome P450 and UDP-glucuronosyltransferase genes, respectively. Furthermore, the target genes of differentially expressed lncRNAs were enriched in Pfam, including chitin bind 4 and gene ontology terms such as structural constituent of the cuticle, revealing their potential mechanism of action on the growth inhibition of S. frugiperda larvae. Insecticide-specific expression of lncRNAs highlights the properties and commonalities of different insecticide-induced lncRNA regulatory mechanisms. To conclude, the results of this study provide new insights and perspectives on the use of 23 insecticides via lncRNA regulation of mRNAs.


Assuntos
Inseticidas , Mariposas , Praguicidas , RNA Longo não Codificante , Animais , Inseticidas/farmacologia , Spodoptera , Larva , RNA Longo não Codificante/genética , Mariposas/genética
3.
BMC Genomics ; 24(1): 332, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322453

RESUMO

The rich genetic diversity in Citrullus lanatus and the other six species in the Citrullus genus provides important sources in watermelon breeding. Here, we present the Citrullus genus pan-genome based on the 400 Citrullus genus resequencing data, showing that 477 Mb contigs and 6249 protein-coding genes were absent in the Citrullus lanatus reference genome. In the Citrullus genus pan-genome, there are a total of 8795 (30.5%) genes that exhibit presence/absence variations (PAVs). Presence/absence variation (PAV) analysis showed that a lot of gene PAV were selected during the domestication and improvement, such as 53 favorable genes and 40 unfavorable genes were identified during the C. mucosospermus to C. lanatus landrace domestication. We also identified 661 resistance gene analogs (RGAs) in the Citrullus genus pan-genome, which contains 90 RGAs (89 variable and 1 core gene) located on the pangenome additional contigs. By gene PAV-based GWAS, 8 gene presence/absence variations were found associated with flesh color. Finally, based on the results of gene PAV selection analysis between watermelon populations with different fruit colors, we identified four non-reference candidate genes associated with carotenoid accumulation, which had a significantly higher frequency in the white flesh. These results will provide an important source for watermelon breeding.


Assuntos
Citrullus , Citrullus/genética , Domesticação , Melhoramento Vegetal , Genoma de Planta , Análise de Sequência de DNA
4.
BMC Genomics ; 24(1): 46, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707768

RESUMO

Terpenoids are important compounds associated with the pest and herbivore resistance mechanisms of plants; consequently, it is essential to identify and explore terpene synthase (TPS) genes in maize. In the present study, we identified 31 TPS genes based on a pan-genome of 26 high-quality maize genomes containing 20 core genes (present in all 26 lines), seven dispensable genes (present in 2 to 23 lines), three near-core genes (present in 24 to 25 lines), and one private gene (present in only 1 line). Evaluation of ka/ks values of TPS in 26 varieties revealed that TPS25 was subjected to positive selection in some varieties. Six ZmTPS had ka/ks values less than 1, indicating that they were subjected to purifying selection. In 26 genomes, significant differences were observed in ZmTPS25 expression between genes affected by structural variation (SV) and those not affected by SV. In some varieties, SV altered the conserved structural domains resulting in a considerable number of atypical genes. The analysis of RNA-seq data of maize Ostrinia furnacalis feeding revealed 10 differentially expressed ZmTPS, 9 of which were core genes. However, many atypical genes for these responsive genes were identified in several genomes. These findings provide a novel resource for functional studies of ZmTPS.


Assuntos
Alquil e Aril Transferases , Zea mays , Zea mays/genética , Zea mays/metabolismo , Terpenos/metabolismo , Alquil e Aril Transferases/genética , Plantas/metabolismo
5.
Trials ; 22(1): 701, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34649610

RESUMO

INTRODUCTION: Hepatitis B-related compensated liver cirrhosis is related to a higher risk of hepatocellular carcinoma, and antiviral therapy is the preferred method. As the pathological mechanisms of liver fibrosis are complex, drugs developed for a single target are difficult to be effective in clinical practice, so there are no chemical drugs or biological drugs with clear efficacy available for clinical application at present. Traditional Chinese medicine is a kind of medical science that has been gradually formed during thousands of years and continuously enriched by the people of all ethnic groups in China. Traditional Chinese medicine shows curative effects in the treatment of liver diseases, especially in the field of liver fibrosis prevention and treatment. This study aims to test the integrative medicine (Chinese medicine plus antiviral therapy) effective on lowing hepatocellular carcinoma risk among patients with hepatitis-related compensated liver cirrhosis. METHODS AND ANALYSIS: This is a multi-center randomized controlled trial, and a total of 5 hospitals and 802 patients will be involved in. All the subjects are randomly allocated to the YinQiSanHuang Jiedu decoction (YQSHD) group (n = 401) or the placebo group (n = 401). The YQSHD group receives YQSHD granule with entecavir (ETV), and the placebo group receives YQSHD placebo with ETV. The treatment period will last for 52 weeks, and the follow-up period for 52 ± 2 weeks. The primary outcome measure is the annual incidence of HCC. Outcomes will be assessed at baseline and after treatment. The objective of this trial is "the integrative of YQSHD with ETV reduce the annual incidence of HCC to 1%." ETHICS AND DISSEMINATION: The protocol has been approved by the Medical Ethics Committee of Guang'anmen Hospital, China (No.2019-006-KY), and the other centers in the trial will not begin recruiting until the local ethical approval has been obtained. Trial final results will be disseminated via publication. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900021532 . Registered on February 26, 2019.


Assuntos
Carcinoma Hepatocelular , Medicamentos de Ervas Chinesas , Hepatite B , Neoplasias Hepáticas , Antivirais/efeitos adversos , Carcinoma Hepatocelular/tratamento farmacológico , Método Duplo-Cego , Medicamentos de Ervas Chinesas/efeitos adversos , Hepatite B/diagnóstico , Hepatite B/tratamento farmacológico , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
6.
iScience ; 24(9): 103028, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34522868

RESUMO

p-Methyl benzaldehyde (p-MBA) is a class of key chemical intermediates of pharmaceuticals. Conventional industrial processes for p-MBA production involve the consecutive photochlorination, amination, and acid hydrolysis of petroleum-derived p-xylene, while producing vast pollutants and waste water. Herein, we report a direct, green route for selective synthesis of p-MBA from acetaldehyde using a diphenyl prolinol trimethylsilyl ether catalyst. The optimized p-MBA selectivity is up to 90% at an acetaldehyde conversion as high as 99.8%. Intermediate structure and 18O-isotope data revealed that the conversion of acetaldehyde to p-methylcyclohexadienal intermediates proceeds in an enamine-iminium intermediate mechanism. Then, controlled experiments and D-isotope results indicated that the dehydrogenation of p-methylcyclohexadienal to p-MBA and H2 is catalyzed by the same amines through an iminium intermediate. This is an example that metal-free amines catalyze the dehydrogenation (releasing H2), rather than using metals or stoichiometric oxidants.

7.
Trials ; 21(1): 482, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503608

RESUMO

INTRODUCTION: Chronic hepatitis B (CHB) is a global public health problem. Antiviral therapy is the primary treatment. Studies have shown that a combined therapy of traditional Chinese medicine (TCM) and conventional antiviral drugs has better efficacy than conventional antiviral for treatment of CHB. YinQiSanHuang-antiviral decoction (YQSH) is a TCM compound preparation that has shown an effect on anti-hepatitis B virus and on slowing progression of hepatitis B-related liver diseases. To evaluate the efficacy and safety of YQSH combined with entecavir and its preventive effect on hepatitis B cirrhosis, we designed this randomized, double-blind and placebo-controlled trial. The objective is that the combination of YinQiSanHuang-antiviral decoction with entecavir will reduce the annual incidence of liver fibrosis/cirrhosis to 1%. METHODS: This is a multicenter, randomized, placebo-controlled, double-blinded trial involving five hospitals. A total of 802 patients are randomly allocated to two groups: the YQSH group (n = 401) or the placebo group (n = 401). The YQSH group receives YQSH with entecavir; the placebo group receives granules of placebo with entecavir. Patients receive treatment for 52 weeks and then are followed up for 52 ± 2 weeks. The primary outcome measure is the annual incidence of cirrhosis. The secondary outcome measures are hepatitis B virus DNA negative rate, hepatitis B surface antigen negative rate, hepatitis B e antigen seroconversion rate, liver function (alanine aminotransferase, aspartate aminotransferase , gamma-glutamyl transferase , alkaline phosphatase , serum albumin, and total bilirubin), spleen thickness, evaluation scores of patients' clinical symptoms, and safety assessment. Outcomes will be assessed at baseline and after treatment. DISCUSSION: Combination therapy could become a trend for treatment of CHB, and this trial expects to provide credible clinical evidence for the future combination of TCM and conventional antiviral drugs for the treatment of CHB. TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR1900021521. Registered on 25 February 2019.


Assuntos
Antivirais/uso terapêutico , Medicamentos de Ervas Chinesas/administração & dosagem , Hepatite B Crônica/tratamento farmacológico , Cirrose Hepática/prevenção & controle , Medicina Tradicional Chinesa/métodos , Método Duplo-Cego , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/efeitos adversos , Guanina/análogos & derivados , Guanina/uso terapêutico , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Hepatite B Crônica/complicações , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/virologia , Testes de Função Hepática , Medicina Tradicional Chinesa/efeitos adversos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Resultado do Tratamento
8.
Chem Commun (Camb) ; 55(70): 10420-10423, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31407748

RESUMO

Herein, we have shown that the [Ca-O-P] sites exposed on hydroxyapatite are clearly responsible for C-C formation in ethanol direct-coupling, and their high density accelerates the C-C coupling rate and boosts C6-12 alcohol production. Notably, nanowire-like hydroxyapatite exhibited 30.4% selectivity to n-butanol and 63.9% selectivity to C6-12OH at a conversion of 45.7% at 325 °C, and thereby close to 30% yield of C6-12OH, which is greatly higher than that using the state-of-the-art catalysts (6%).

9.
Ann Transl Med ; 7(22): 692, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31930093

RESUMO

Infantile hemangioma (IH) is a common benign tumor, which mostly resolves spontaneously; however, children with high-risk IH need treatment. Currently, the recognized first-line treatment regimen for IH is oral propranolol, but research on the pathogenesis of IH has led to the identification of new therapeutic targets, which have shown good curative effects, providing more options for disease treatment. This article summarizes the applications of different medications, dosages, and routes of administration for the treatment of IH. In addition to drug therapy, this article also reviews current therapeutic options for IH such as laser therapy, surgical treatment, and observation. To provide the best treatment, therapeutic regimens for IH should be selected based on the child's age, the size and location of the lesion, the presence of complications, the implementation conditions, and the potential outcomes of the treatment.

10.
Angew Chem Int Ed Engl ; 54(47): 13994-8, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26332348

RESUMO

In heterogeneous catalysis, supports play a crucial role in modulating the geometric and electronic structure of the active metal phase for optimizing the catalytic performance. A γ-Al2O3 nanosheet that contains 27% pentacoordinate Al(3+) sites can nicely disperse and stabilize raft-like Pt-Sn clusters as a result of strong interactions between metal and support. Consequently, there are strong electronic interactions between the Pt and Sn atoms, resulting in an increase in the electron density of the Pt sites. When used in the propane dehydrogenation reaction, this catalyst displayed an excellent specific activity for propylene formation with >99% selectivity, and superior anti-coking and anti-sintering properties. Its exceptional ability to maintain the high activity and stability at ultrahigh space velocities further showed that the sheet construction of the catalyst facilitated the kinetic transfer process.

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