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1.
Proc Natl Acad Sci U S A ; 121(11): e2319390121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437562

RESUMO

Water-energy sustainability will depend upon the rapid development of advanced pressure-driven separation membranes. Although energy-efficient, water-treatment membranes are constrained by ubiquitous fouling, which may be alleviated by engineering self-cleaning membrane interfaces. In this study, a metal-polyphenol network was designed to direct the armorization of catalytic nanofilms (ca. 18 nm) on inert polymeric membranes. The chelation-directed mineralized coating exhibits high polarity, superhydrophilicity, and ultralow adhesion to crude oil, enabling cyclable crude oil-in-water emulsion separation. The in-place flux recovery rate exceeded 99.9%, alleviating the need for traditional ex situ cleaning. The chelation-directed nanoarmored membrane exhibited 48-fold and 6.8-fold figures of merit for in-place self-cleaning regeneration compared to the control membrane and simple hydraulic cleaning, respectively. Precursor interaction mechanisms were identified by density functional theory calculations. Chelation-directed armorization offers promise for sustainable applications in catalysis, biomedicine, environmental remediation, and beyond.

2.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34969860

RESUMO

Mixed matrix membranes (MMMs) are one of the most promising solutions for energy-efficient gas separation. However, conventional MMM synthesis methods inevitably lead to poor filler-polymer interfacial compatibility, filler agglomeration, and limited loading. Herein, inspired by symbiotic relationships in nature, we designed a universal bottom-up method for in situ nanosized metal organic framework (MOF) assembly within polymer matrices. Consequently, our method eliminating the traditional postsynthetic step significantly enhanced MOF dispersion, interfacial compatibility, and loading to an unprecedented 67.2 wt % in synthesized MMMs. Utilizing experimental techniques and complementary density functional theory (DFT) simulation, we validated that these enhancements synergistically ameliorated CO2 solubility, which was significantly different from other works where MOF typically promoted gas diffusion. Our approach simultaneously improves CO2 permeability and selectivity, and superior carbon capture performance is maintained even during long-term tests; the mechanical strength is retained even with ultrahigh MOF loadings. This symbiosis-inspired de novo strategy can potentially pave the way for next-generation MMMs that can fully exploit the unique characteristics of both MOFs and matrices.

3.
Ann Surg Oncol ; 31(6): 3830-3838, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38245649

RESUMO

BACKGROUND: The study aimed to evaluate the efficacy of using near-infrared fluorescent imaging (NIRF) imaging with indocyanine green as an intraoperative tool for achieving complete mediastinal lymph node (LN) resection. PATIENTS AND METHODS: Between September 2019 and July 2021, patients with potential for esophagectomy due to middle and lower thoracic esophageal cancer were enrolled in this study. All patients were scheduled for NIRF-guided mediastinal lymphadenectomy during esophageal cancer surgery and were appropriately assigned to the NIRF group. Patients who underwent esophagectomy between September 2017 and September 2019 were assigned to the historical control group upon satisfying the inclusion/exclusion criteria. Surgical outcomes and the number of removed LNs were compared between the two groups using 1:1 propensity score matching. RESULTS: Of 67 eligible patients, 59 patients were included in the NIRF group after postsurgical exclusions. The operative time was significantly shorter in the NIRF group than in the historical control group [180 (140-420) min versus 202 (137-338) min; P < 0.001]. The incidence of postoperative chylothorax and hoarseness were significantly lower in the NIRF group than in the historical control group (0% versus 10.2 %; P = 0.036, 3.4% versus 13.6%; P = 0.047). The number of dissected total LNs, mediastinal LNs, and negative LNs was significantly larger in the NIRF group than in the historical control group. The number of overall metastatic LNs and abdominal LNs was comparable between the two groups. CONCLUSIONS: NIRF imaging can assist in the thorough and complete mediastinal LNs dissections without increasing complications in patients undergoing esophagectomy.


Assuntos
Neoplasias Esofágicas , Esofagectomia , Verde de Indocianina , Excisão de Linfonodo , Mediastino , Humanos , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/diagnóstico por imagem , Masculino , Excisão de Linfonodo/métodos , Feminino , Esofagectomia/métodos , Esofagectomia/efeitos adversos , Pessoa de Meia-Idade , Mediastino/cirurgia , Mediastino/patologia , Complicações Pós-Operatórias , Seguimentos , Idoso , Imagem Óptica/métodos , Prognóstico , Cirurgia Assistida por Computador/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos
4.
J Clin Nurs ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38867609

RESUMO

AIMS: To investigate the prevalence of physical inactivity in older adults living in nursing homes and explore the determinants of physical inactivity by using the Capability, Opportunity, Motivation-Behaviour model. DESIGN: A multisite, cross-sectional study was performed by convenience sampling and questionnaire survey. METHODS: A total of 390 nursing home residents were recruited from three nursing homes in Southern China from May 2022 to April 2023. The participants completed a self-designed general information questionnaire, Physical Activity Scale for the Elderly, Self-Efficacy for Exercise Scale, Exercise Benefits Scale, Patient Health Questionnaire-9 and the Short Physical Performance Battery test. Descriptive statistics, univariate analysis, Spearman correlation analysis, and ordinal logistic regression were applied for data analysis. RESULTS: The prevalence of physical inactivity among the nursing home residents reached 88.46%. Ordinal logistic regression results showed that exercise self-efficacy, perceived exercise benefits, physical function, availability of physical activity instruction, having depression, number of chronic diseases and living with spouse were the main influencing determinants of physical inactivity and explained 63.7% of the variance. CONCLUSIONS: Physical inactivity was considerable in nursing home residents in China and influenced by complex factors. Tailored measures should be designed and implemented based on these factors to enhance physical activity while considering the uniqueness of Chinese culture. IMPLICATIONS FOR THE PROFESSION AND PATIENT CARE: Healthcare professionals should enhance physical activity of residents by increasing benefits understanding, boosting self-efficacy, improving physical function, alleviating depression and integrating personalized physical activity guidance into routine care services. And more attention should be paid to the residents who had more chronic diseases or did not live with spouse. IMPACT: Physical inactivity is a significant problem in nursing home residents. Understanding physical inactivity and its determinants enables the development of tailored interventions to enhance their physical activity level. REPORTING METHOD: This study was reported conforming to the STROBE statement. PATIENTS OR PUBLIC CONTRIBUTION: Nursing home residents who met the inclusion criteria were recruited.

5.
Geriatr Nurs ; 58: 104-110, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38788557

RESUMO

This study explored the status of adverse event reporting attitudes and its predictors among nursing staff in Chinese nursing homes. A cross-sectional study was conducted with 475 nursing staff, and they completed sociodemographic and facility-related questionnaire, Incident Reporting Attitude Scale, Adverse Event Reporting Awareness Scale, and Nursing Home Survey on Patient Safety Culture. Univariate analysis and multiple linear regression models were performed. The mean score for adverse event reporting attitude was 125.87 (SD=15.35). The predictors included individual variables, such as education level (ß=0.129, p = 0.001) and working years (ß=-0.102, p = 0.007), and organizational variables, such as patient safety culture (ß=0.503, p < 0.001) and adverse event reporting awareness (ß=0.261, p < 0.001). These factors explained 35.3 % of total variance. Managers in nursing homes should strengthen team-targeted education and training for nursing staff with longer working years and lower educational backgrounds. Meanwhile, a simplified and non-punitive reporting system should be established to create positive safety management climate.

6.
Angew Chem Int Ed Engl ; 63(1): e202315607, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37983684

RESUMO

Membrane technology is rapidly gaining broad attraction as a viable alternative for carbon capture to mitigate increasingly severe global warming. Emerging CO2 -philic membranes have become crucial players in efficiently separating CO2 from light gases, leveraging their exceptional solubility-selectivity characteristics. However, economic and widespread deployment is greatly dependent on the boosted performance of advanced membrane materials for carbon capture. Here, we design a unique gel membrane composed of CO2 -philic molecules for accelerating CO2 transportation over other gases for ultrapermeable carbon capture. The molecular design of such soft membranes amalgamates the advantageous traits of augmented permeation akin to liquid membranes and operational stability akin to solid membranes, effectively altering the membrane's free volume characteristics validated by both experiments and molecular dynamics simulation. Surprisingly, gas diffusion through the free-volume-tuned gel membrane undergoes a 9-fold improvement without compromising the separation factor for the superior solubility selectivity of CO2 -philic materials, and CO2 permeability achieves a groundbreaking record of 5608 Barrer surpassing the capabilities of nonfacilitated CO2 separation materials and exceeding the upper bound line established in 2019 even by leading-edge porous polymer materials. Our designed gel membrane can maintain exceptional separation performance during prolonged operation, enabling the unparalleled potential of solubility-selective next-generation materials towards sustainable carbon capture.

7.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(1): 155-160, 2023 Feb.
Artigo em Zh | MEDLINE | ID: mdl-36861170

RESUMO

Extracellular signal-regulated kinase 1/2 (ERK1/2) is a serine/threoninekinase involved in the signal transduction cascade of Ras-Raf-mitogen-activated protein kinase (MEK)-ERK.It participates in the cell growth,proliferation and even invasion by regulating gene transcription and expression.The occurrence of a variety of diseases such as lung cancer,liver cancer,ovarian cancer,cervical cancer,endometriosis,and preeclampsia,as well the metastasis and disease progression,is closely associated with the regulation of cell invasion by ERK1/2 signaling pathway.Therefore,exploring the regulation of ERK1/2 signaling on cell invasion and its role in pathogenesis of diseases may help to develop more effective treatment schemes.This article introduces recent progress in the regulation of ERK1/2 signaling on cell invasion and the role of such regulation in diseases,with a view to give new insights into the clinical treatment of ERK 1/2-related diseases.


Assuntos
Proteínas Quinases Ativadas por Mitógeno , Transdução de Sinais , Feminino , Gravidez , Humanos , Proteína Quinase 3 Ativada por Mitógeno , Ciclo Celular , Proliferação de Células
8.
Angew Chem Int Ed Engl ; 62(23): e202302931, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37015013

RESUMO

Two-dimensional graphene oxide (GO) membranes are gaining popularity as a promising means to address global water scarcity. However, current GO membranes fail to sufficiently exclude angstrom-sized ions from solution. Herein, a de novo "posterior" interfacial polymerization (p-IP) strategy is reported to construct a tailor-made polyamide (PA) network in situ in an ultrathin GO membrane to strengthen size exclusion while imparting a positively charged membrane surface to repel metal ions. The electrostatic repulsion toward metal ions, coupled with the reinforced size exclusion, synergistically drives the high-efficiency metal ion separation through the synthesized positively charged GO framework (PC-GOF) membrane. This dual-mechanism-driven PC-GOF membrane exhibits superior metal ion rejection, anti-fouling ability, good operational stability, and ultra-high permeance (five times that of pristine GO membranes), enabling a sound step towards a sustainable water-energy-food nexus.

9.
Org Biomol Chem ; 20(19): 3902-3906, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35502883

RESUMO

A photoexcited sulfenylation of C(sp3)-H bonds in amides is developed for the synthesis of sulfenyl amides using thiosulfonates as a sulfur source. In the presence of easily available and inexpensive Na2-eosin Y, TBHP and K2CO3, various sulfenyl amides can be obtained under the irradiation of blue light at room temperature.


Assuntos
Amidas , Enxofre , Amidas/química , Enxofre/química
10.
Support Care Cancer ; 30(6): 5259-5267, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35274190

RESUMO

PURPOSE: Resilience plays an important role in helping individuals to adapt to adversity and improve their psychosocial outcomes. This study aims to examine the mediating role of coping in the relationship between family function and resilience in adolescents and young adults (AYAs) who have a parent with lung cancer. METHOD: A total of 135 AYAs with a lung cancer parent were recruited from a tertiary grade A cancer center in southern China, and investigated using a self-designed general information questionnaire, the Resilience Scale for Chinese Adolescents, the Simplified Coping Style Questionnaire, and the Family Adaptation, Partnership, Growth, Affection, Resolve index. RESULTS: The mean score of AYAs' resilience was (3.61 ± 0.49), and its influencing factors included AYAs' years in work, family function, and positive coping. The total effect of family function on resilience was significant (total effect = 0.38, 95% CI [0.048-0.115]), and a positive indirect effect was identified for family function on resilience via positive coping (indirect effect = 0.10, 95% CI [0.005-0.043]). CONCLUSION: Family functioning can facilitate resilience either directly or by promoting positive coping. This study suggests that individualized interventions can be made to improve resilience by promoting family function, or by enhancing positive coping in AYAs with a lung cancer parent.


Assuntos
Neoplasias Pulmonares , Resiliência Psicológica , Adaptação Psicológica , Adolescente , Humanos , Pais , Inquéritos e Questionários , Adulto Jovem
11.
Int J Nurs Pract ; 28(4): e13045, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35274411

RESUMO

AIM: The purpose of this study was to translate the Stoma-quality of life into Chinese and evaluate its psychometric properties in Chinese patients. BACKGROUND: Quality of life is an important issue for patients with colostomy, and its appropriate and precise measurement is beneficial to promoting better care. The Stoma-quality of life questionnaire has been widely used; however, the validity and reliability of its Chinese version has not been determined. DESIGN: A cross-sectional validation study was conducted. METHODS: We translated the Stoma-quality of life into Chinese using standardized methods. Then it was psychometrically tested on a convenience sample of 513 patients with colostomy. Construct validity was evaluated via exploratory factor analysis and confirmatory factor analysis. Reliability was measured with Cronbach's alpha and the split-half Spearman-Brown coefficient. RESULTS: The content validity, the Cronbach's α coefficient and the Spearman-Brown split-half reliability coefficient indicated adequate validity and reliability. The exploratory factor analysis yielded four common factors, and the cumulative variance contribution rate was 67.5%. Moreover, the confirmatory factor analysis showed a good model fit. CONCLUSION: This study confirmed that the Chinese version of Stoma-quality of life is an effective and reliable measurement for evaluating the quality of life of patients with colostomy.


Assuntos
Qualidade de Vida , Neoplasias Retais , China , Colostomia , Estudos Transversais , Humanos , Psicometria/métodos , Reprodutibilidade dos Testes , Inquéritos e Questionários
12.
Angew Chem Int Ed Engl ; 61(46): e202212816, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36148532

RESUMO

Organic solvent nanofiltration (OSN) is an emerging membrane separation technology, which urgently requires robust, easily processed, OSN membranes possessing high permeance and small solutes-selectivity to facilitate enhanced industrial uptake. Herein, we describe the use of two 2,2'-biphenol (BIPOL) derivatives to fabricate hyper-crosslinked, microporous polymer nanofilms through IP. Ultra-thin, defect-free polyesteramide/polyester nanofilms (≈5 nm) could be obtained readily due to the relatively large molecular size and ionized nature of the BIPOL monomers retarding the rate of the IP. The enhanced microporosity arises from the hyper-crosslinked network structure and monomer rigidity. Specifically, the amino-BIPOL/PAN membrane exhibits extraordinary permselectivity performances with molecular weight cut-off as low as 233 Da and MeOH permeance of ≈13 LMH/bar. Precise separation of small dye mixtures with similar M.W. based on both their charge and molecular size are achieved.

13.
Mar Drugs ; 19(11)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34822471

RESUMO

Crustins are widely distributed among different crustacean groups. They are characterized by a whey acidic protein (WAP) domain, and most examined Crustins show activity against Gram-positive bacteria. This study reports two Crustins, Al-crus 3 and Al-crus 7, from hydrothermal vent shrimp, Alvinocaris longirostris. Al-crus 3 and Al-crus 7 belong to Crustin Type IIa, with a similarity of about 51% at amino acid level. Antibacterial assays showed that Al-crus 3 mainly displayed activity against Gram-positive bacteria with MIC50 values of 10-25 µM. However, Al-crus 7 not only displayed activity against Gram-positive bacteria but also against Gram-negative bacteria Imipenem-resistant Acinetobacter baumannii, in a sensitive manner. Notably, in the effective antibacterial spectrum, Methicillin-sensitive Staphylococcus aureus, Escherichia coli (ESBLs) and Imipenem-resistant A. baumannii were drug-resistant pathogens. Narrowing down the sequence to the WAP domain, Al-crusWAP 3 and Al-crusWAP 7 demonstrated antibacterial activities but were weak. Additionally, the effects on bacteria did not significantly change after they were maintained at room temperature for 48 h. This indicated that Al-crus 3 and Al-crus 7 were relatively stable and convenient for transportation. Altogether, this study reported two new Crustins with specific characteristics. In particular, Al-crus 7 inhibited Gram-negative imipenem-resistant A. baumannii.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Penaeidae , Animais , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Organismos Aquáticos , Farmacorresistência Bacteriana/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Fontes Hidrotermais , Testes de Sensibilidade Microbiana
14.
BMC Genomics ; 21(1): 245, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32188400

RESUMO

BACKGROUND: Sheath blight (SB), caused by Rhizoctonia solani, is a common rice disease worldwide. Currently, rice cultivars with robust resistance to R. solani are still lacking. To provide theoretic basis for molecular breeding of R. solani-resistant rice cultivars, the changes of transcriptome profiles in response to R. solani infection were compared between a moderate resistant cultivar (Yanhui-888, YH) and a susceptible cultivar (Jingang-30, JG). RESULTS: In the present study, 3085 differentially express genes (DEGs) were detected between the infected leaves and the control in JG, with 2853 DEGs in YH. A total of 4091 unigenes were significantly upregulated in YH than in JG before infection, while 3192 were significantly upregulated after infection. Further analysis revealed that YH and JG showed similar molecular responses to R. solani infection, but the responses were earlier in JG than in YH. Expression levels of trans-cinnamate 4-monooxygenase (C4H), ethylene-insensitive protein 2 (EIN2), transcriptome factor WRKY33 and the KEGG pathway plant-pathogen interaction were significantly affected by R. solani infection. More importantly, these components were all over-represented in YH cultivar than in JG cultivar before and/or after infection. CONCLUSIONS: These genes possibly contribute to the higher resistance of YH to R. solani than JG and were potential target genes to molecularly breed R. solani-resistant rice cultivar.


Assuntos
Oryza/genética , Oryza/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , Rhizoctonia , Transcriptoma/genética , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas
16.
J Med Virol ; 90(11): 1675-1680, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29574888

RESUMO

The first three cases of confirmed infection with the virus in China were documented between May 10 and May 15, 2009. Although the clinical characteristics of the H1N1 pneumonia were described in clinical reports, the therapy has few been described. Therefore, we report our experiences of 53 cases of the H1N1 pneumonia with treatment. We describe clinical characteristic of 53 patients who were hospitalized for laboratory-confirmed H1N1 pneumonia at the 2nd Clinical College of Harbin Medical University. In addition, we measure the role of corticosteroid, mechanical ventilation, and non-corticosteroid antiviral therapy in the management of pneumonia patients with novel H1N1 infection. Real-time reverse-transcriptase-polymerase chain (RT-PCR) testing was used to confirm infection. The outcome of therapy was compared in scores of PaO2 and CT. The data was statistical analyzed by the Shapiro-Wilk, anova, Student-Newman-Keuls Test, and Kruskal-Wallis Test. The most common symptoms were dyspnea. In moderate ill patients, the changes in the increased PaO2 were lower in the non-corticosteroid antiviral therapy group than in the combination of corticosteroid and non-corticosteroid antiviral therapy after 5 days' therapy. The therapy protocol of non-corticosteriod + mechanical ventilation played important role in the recovery of severe ill patients.


Assuntos
Corticosteroides/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/complicações , Influenza Humana/virologia , Pneumonia/tratamento farmacológico , Adolescente , Adulto , China , Feminino , Hospitais Universitários , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/patologia , Masculino , Pessoa de Meia-Idade , Pneumonia/patologia , Pneumonia/virologia , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Resultado do Tratamento , Adulto Jovem
17.
Mar Drugs ; 16(3)2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-29510563

RESUMO

N-acetylneuraminic acid (Neu5Ac) based novel pharmaceutical agents and diagnostic reagents are highly required in medical fields. However, N-acetylneuraminate lyase(NAL)for Neu5Ac synthesis is not applicable for industry due to its low catalytic efficiency. In this study, we biochemically characterized a deep-sea NAL enzyme (abbreviated form: MyNal) from a symbiotic Mycoplasma inhabiting the stomach of a deep-sea isopod, Bathynomus jamesi. Enzyme kinetic studies of MyNal showed that it exhibited a very low Km for both cleavage and synthesis activities compared to previously described NALs. Though it favors the cleavage process, MyNal out-competes the known NALs with respect to the efficiency of Neu5Ac synthesis and exhibits the highest kcat/Km values. High expression levels of recombinant MyNal could be achieved (9.56 mol L-1 culture) with a stable activity in a wide pH (5.0-9.0) and temperature (40-60 °C) range. All these features indicated that the deep-sea NAL has potential in the industrial production of Neu5Ac. Furthermore, we found that the amino acid 189 of MyNal (equivalent to Phe190 in Escherichia coli NAL), located in the sugar-binding domain, GX189DE, was also involved in conferring its enzymatic features. Therefore, the results of this study improved our understanding of the NALs from different environments and provided a model for protein engineering of NAL for biosynthesis of Neu5Ac.


Assuntos
Proteínas de Bactérias/química , Isópodes/microbiologia , Mycoplasma/química , Ácido N-Acetilneuramínico/biossíntese , Oxo-Ácido-Liases/química , Sequência de Aminoácidos , Animais , Organismos Aquáticos/química , Organismos Aquáticos/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Biotecnologia/métodos , Clonagem Molecular , Ensaios Enzimáticos , Mutagênese , Oxo-Ácido-Liases/genética , Oxo-Ácido-Liases/isolamento & purificação , Oxo-Ácido-Liases/metabolismo , Domínios Proteicos , Engenharia de Proteínas/métodos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Simbiose
18.
New Phytol ; 215(4): 1490-1502, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28675474

RESUMO

In petunia, the production of volatile benzenoids/phenylpropanoids determines floral aroma, highly regulated by development, rhythm and ethylene. Previous studies identified several R2R3-type MYB trans-factors as positive regulators of scent biosynthesis in petunia flowers. Ethylene response factors (ERFs) have been shown to take part in the signal transduction of hormones, and regulation of metabolism and development processes in various plant species. Using virus-induced gene silencing technology, a negative regulator of volatile benzenoid biosynthesis, PhERF6, was identified by a screen for regulators of the expression of genes related to scent production. PhERF6 expression was temporally and spatially connected with scent production and was upregulated by exogenous ethylene. Up-/downregulation of the mRNA level of PhERF6 affected the expression of ODO1 and several floral scent-related genes. PhERF6 silencing led to a significant increase in the concentrations of volatiles emitted by flowers. Yeast two-hybrid, bimolecular fluorescence complementation and co-immunoprecipitation assays indicated that PhERF6 interacted with the N-terminus of EOBI, which includes two DNA binding domains. Our results show that PhERF6 negatively regulates volatile production in petunia flowers by competing for the binding of the c-myb domains of the EOBI protein with the promoters of genes related to floral scent.


Assuntos
Flores/metabolismo , Petunia/metabolismo , Proteínas de Plantas/metabolismo , Núcleo Celular/metabolismo , Regulação para Baixo/genética , Ensaio de Desvio de Mobilidade Eletroforética , Etilenos/metabolismo , Flores/genética , Fluorescência , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Genes de Plantas , Odorantes , Petunia/genética , Proteínas de Plantas/química , Regiões Promotoras Genéticas , Propanóis/metabolismo , Ligação Proteica , Domínios Proteicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Frações Subcelulares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/genética , Volatilização
19.
Neurochem Res ; 42(4): 997-1005, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27995497

RESUMO

Chemotherapy has always been one of the most effective ways in combating human glioma. However, the high metastatic potential and resistance toward standard chemotherapy severely hindered the chemotherapy outcomes. Hence, searching effective chemotherapy drugs and clarifying its mechanism are of great significance. Salinomycin an antibiotic shows novel anticancer potential against several human tumors, including human glioma, but its mechanism against human glioma cells has not been fully elucidated. In the present study, we demonstrated that salinomycin treatment time- and dose-dependently inhibited U251 and U87 cells growth. Mechanically, salinomycin-induced cell growth inhibition against human glioma was mainly achieved by induction of G1-phase arrest via triggering reactive oxide species (ROS)-mediated DNA damage, as convinced by the activation of histone, p53, p21 and p27. Furthermore, inhibition of ROS accumulation effectively attenuated salinomycin-induced DNA damage and G1 cell cycle arrest, and eventually reversed salinomycin-induced cytotoxicity. Importantly, salinomycin treatment also significantly inhibited the U251 tumor xenograft growth in vivo through triggering DNA damage-mediated cell cycle arrest with involvement of inhibiting cell proliferation and angiogenesis. The results above validated the potential of salinomycin-based chemotherapy against human glioma.


Assuntos
Dano ao DNA/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Glioma/metabolismo , Piranos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Dano ao DNA/fisiologia , Relação Dose-Resposta a Droga , Pontos de Checagem da Fase G1 do Ciclo Celular/fisiologia , Glioma/tratamento farmacológico , Glioma/patologia , Humanos , Masculino , Camundongos , Camundongos Nus , Piranos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
20.
Org Biomol Chem ; 15(3): 649-661, 2017 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-27973631

RESUMO

A diastereoselective approach to trans-4-hydroxy-5-substituted 2-pyrrolidinones 1 (P1 = TBS, P2 = H) has been developed through a stereoselective tandem Barbier process of (R,SRS)-8 with alkyl and aryl bromide. The stereochemistry at the C-5 stereogenic center of the trans-4-hydroxy-5-substituted 2-pyrrolidinones was solely controlled by α-alkoxy substitution. This effective approach was successfully used to prepare a variety of substituted (3R,4S)-statines 2. In addition, two bioactive natural products of (+)-preussin 4 and hapalosin 5 were effectively synthesized through this stereoselective tandem Barbier process.


Assuntos
Aminoácidos/síntese química , Anisomicina/análogos & derivados , Depsipeptídeos/síntese química , Lactamas/síntese química , Lactonas/síntese química , Pirrolidinonas/síntese química , Aminoácidos/química , Anisomicina/síntese química , Anisomicina/química , Depsipeptídeos/química , Lactamas/química , Lactonas/química , Conformação Molecular , Pirrolidinonas/química , Estereoisomerismo
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