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1.
Phys Chem Chem Phys ; 26(5): 3869-3879, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38226609

RESUMO

Rare-earth-doped silica-based composite glasses (Re-SCGs) are widely used as high-quality laser gain media in defense, aerospace, energy, power, and medical applications. The variable regional chemical environments of Re-SCGs can induce new photoluminescence properties of rare-earth ions but can cause the selective aggregation of rare-earth ions, limiting the application of Re-SCGs in the field of high-power lasers. Here, topological engineering is proposed to adjust the degree of cross-linking of phase-separation network chains in Re-SCGs. A combination of experimental and theoretical characterization techniques suggested that the selective aggregation of rare-earth ions originates from the formation of phase-separated structures in glasses. The decomposition of nanoscale phase separation structures to the sub-nanometer scale, enabled by incorporating Al3+ ions, not only maintains the high luminescence efficiency of rare earth ions but also increases light transmittance and reduces light scattering. Furthermore, our investigation encompassed the exploration of the inhibitory mechanism of Al3+ ions on phase-separation structures, as well as their influence on the spectral characteristics of Re-SCGs. This work provides a new design concept for composite glass materials doped with rare-earth ions and could broaden their application in the field of high-power lasers.

2.
Molecules ; 28(8)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37110525

RESUMO

A series of 1,4-naphthoquinone derivatives containing were synthesized as anti-cancer agents and the crystal structure of compound 5a was confirmed by X-ray diffraction. In addition, the inhibitory activities against four cancer cell lines (HepG2, A549, K562, and PC-3) were tested, respectively, and compound 5i showed significant cytotoxicity on the A549 cell line with the IC50 of 6.15 µM. Surprisingly, in the following preliminary biological experiments, we found that compound 5i induced autophagy by promoting the recycling of EGFR and signal transduction in the A549 cell, resulting in the activation of the EGFR signal pathway. The potential binding pattern between compound 5i and EGFR tyrosine kinase (PDB ID: 1M17) was also identified by molecular docking. Our research paves the way for further studies and the development of novel and powerful anti-cancer drugs.


Assuntos
Antineoplásicos , Naftoquinonas , Humanos , Células A549 , Linhagem Celular Tumoral , Proliferação de Células , Simulação de Acoplamento Molecular , Naftoquinonas/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Morte Celular , Receptores ErbB/metabolismo , Autofagia , Ensaios de Seleção de Medicamentos Antitumorais , Relação Estrutura-Atividade
3.
Pest Manag Sci ; 80(3): 1026-1038, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37842924

RESUMO

BACKGROUND: Plant bacterial infections and plant viruses seriously affect the yield and quality of crops. Based on the various activities of tryptanthrin, a series of tryptanthrin analogues bearing F and piperazine moieties were designed, synthesized, and evaluated for their biological activities against three plant bacteria and tobacco mosaic virus (TMV). RESULTS: Bioassay results indicated that compounds 6a-6l displayed excellent antibacterial activities in vitro and 6a-6c and 6g exhibited better antiviral activities against TMV than commercial ribavirin. In particular, 6b showed the most effect on Xanthomonas oryzae pv. oryzae (Xoo) with a half-maximal effective concentration (EC50 ) of 1.26 µg mL-1 , compared with the commercial pesticide bismerthiazol (BT; EC50 = 34.3 µg mL-1 ) and thiodiazole copper (TC; EC50 = 73.3 µg mL-1 ). Meanwhile, 6a also had the best antiviral activity at 500 µg mL-1 for curative, protection, and inactivation purposes, compared with ribavirin in vivo. CONCLUSION: Compound 6b could cause changes in bacterial morphology, induce the accumulation of reactive oxygen species, promote apoptosis of bacterial cells, inhibit the formation of biofilm, and block the growth of Xoo cells. Proteomic analysis revealed major differences in the bacterial secretory system pathways T2SS and T6SS, which inhibited membrane transport. Molecular docking revealed that 6a and 6g could interact with TMV coat protein preventing virus assembly. These results suggest that tryptanthrin analogues bearing F and piperazine moieties could be promising candidate agents for antibacterial and antiviral use in agricultural production. © 2023 Society of Chemical Industry.


Assuntos
Oryza , Quinazolinas , Vírus do Mosaico do Tabaco , Xanthomonas , Ribavirina/metabolismo , Ribavirina/farmacologia , Simulação de Acoplamento Molecular , Piperazina/metabolismo , Piperazina/farmacologia , Proteômica , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antivirais/farmacologia , Doenças das Plantas , Relação Estrutura-Atividade
4.
Pest Manag Sci ; 80(6): 2710-2723, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38358029

RESUMO

BACKGROUND: Xanthomonas oryzae pv. oryzae (Xoo) is often considered one of the most destructive bacterial pathogens causing bacterial leaf blight (BLB), resulting in significant yield and cost losses in rice. In this study, a series of novel derivatives containing the isopropanolamine moiety linked to various substituted phenols and piperazines were designed, synthesized and screened. RESULTS: Antibacterial activity results showed that most compounds had good inhibitory effects on Xoo, among which compound W2 (EC50 = 2.74 µg mL-1) exhibited the most excellent inhibitory activity, and W2 also had a certain curative effect (35.89%) on rice compared to thiodiazole copper (TC) (21.57%). Scanning electron microscopy (SEM) results indicated that compound W2 could cause rupture of the Xoo cell membrane. Subsequently, proteomics and quantitative real-time polymerase chain reaction revealed that compound W2 affected the physiological processes of Xoo and may exert antibacterial activity by targeting the two-component system pathway. Interestingly, W2 upregulated Xoo's methyltransferase to impact on its pathogenicity. CONCLUSION: The present study offers a promising phenolic-piperazine-sopropanolamine compound as an innovative antibacterial strategy by specifically targeting the two-component system pathway and inducing upregulation of methyltransferase to effectively impact Xoo's pathogenicity. © 2024 Society of Chemical Industry.


Assuntos
Antibacterianos , Xanthomonas , Xanthomonas/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Fenóis/farmacologia , Fenóis/química , Desenho de Fármacos , Piperazinas/farmacologia , Piperazinas/química , Piperazinas/síntese química , Oryza/microbiologia , Doenças das Plantas/microbiologia
5.
Pest Manag Sci ; 79(2): 537-547, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36193761

RESUMO

BACKGROUND: Plant bacterial diseases have seriously affected the yield and quality of crops, among which rice bacterial leaf blight (BLB), caused by Xanthomonas oryzae pv. oryzae has seriously affected the yield of rice. As plant-pathogenic bacteria gradually become resistant to existing bactericides, it is necessary to find effective bactericides with novel structures. RESULTS: Herein, a series of compounds containing quinazolin-4(3H)-one and disulfide moieties were designed and synthesized using a facile synthetic method. The bioassay results revealed that most target compounds possessed noticeable antibacterial activity against Xanthomonas oryzae pv. oryzae. Particularly, compound 2-(butyldisulfanyl) quinazolin-4(3H)-one (1) exhibited remarkable antibacterial activity with the half effective concentration (EC50 ) of 0.52 µg mL-1 . Additionally, compound 1 was confirmed to inhibit the growth of the bacteria, change the bacterial morphology, and increase the level of reactive oxygen species. Proteomics, and RT-qPCR analysis results indicated that compound 1 could downregulate the expression of Pil-Chp histidine kinase chpA encoded by the pilL gene, and the potting experiments proved that compound 1 exhibits significant protective activity against BLB. CONCLUSIONS: Compound 1 may weaken the pathogenicity of Xanthomonas oryzae pv. oryzae by inhibiting the bacterial growth and blocking the pili-mediated twitching motility without inducing the bacterial apoptosis. This study indicates that such derivatives could be a promising scaffold to develop a bacteriostat to control BLB. © 2022 Society of Chemical Industry.


Assuntos
Oryza , Xanthomonas , Tiram/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Dissulfetos/farmacologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
6.
World J Clin Cases ; 10(14): 4395-4403, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35663071

RESUMO

BACKGROUND: Depression has been reported to be prevalent in patients with pulmonary tuberculosis (PTB). Moreover, several clinical symptoms of PTB and depression overlap, such as loss of appetite and malnutrition. However, the association between depression and malnutrition in TB patients has not been fully elucidated. AIM: To explore the association between depression and malnutrition in patients with PTB. METHODS: This hospital-based cross-sectional study included patients with PTB in Shanghai Pulmonary Hospital Affiliated to Tongji University from April 2019 to July 2019. The Patient Health Questionnaire-9 (PHQ-9) scale was used to evaluate depre-ssion. The cut-off value was set at 10, and the nutritional state was determined by the body mass index (BMI). In addition, the Quality of Life Instruments for Chronic Diseases was employed to establish the quality of life (QOL). Univariable analysis and multivariable analysis (forward mode) were implemented to identify the independent factors associated with depression. RESULTS: A total of 328 PTB patients were screened for analysis. Eight were excluded for missing demographic data, four excluded for missing nutrition status, and sixteen for missing QOL data. Finally, 300 PTB patients were subjected to analysis. We found that depressive state was present in 225 PTB patients (75%). The ratio of malnutrition in the depressive PTB patients was 45.33%. Our results revealed significantly lower BMI, hemoglobin, and prealbumin in the depression group than in the control group (P < 0.05). Moreover, the social status differed significantly (P < 0.05) between the groups. In addition, glutamic pyruvic transaminase and glutamic oxaloacetic transaminase in the depression group were significantly higher than those in the control group (P < 0.05). Multivariable logistic regression analysis showed that BMI [odds ratio (OR) = 1.21, 95% confidence interval (CI): 1.163-1.257, P < 0.001] and poor social function (OR = 0.95, 95%CI: 0.926-0.974, P = 0.038) were independently associated with depression. CONCLUSION: Malnutrition and poor social function are significantly associated with depressive symptoms in PTB patients. A prospective large-scale study is needed to confirm these findings.

7.
Ann Palliat Med ; 9(5): 3304-3312, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33065785

RESUMO

BACKGROUND: In recent years, disasters occurred frequently all over the world, and the role of nurses in public health emergencies and disaster emergencies was highlighted under the background of the covid19 epidemic. However, there was a lack of education and evaluation. Our study aims to cross-cultural adapt the Nurses' Perceptions of Disaster Core Competencies Scale (NPDCC) and evaluate the reliability and validity of the Chinese version. METHODS: We translated the scale following the translation-integration-back translation-expert review procedure, adapted according to Chinese culture. We evaluated the reliability and validity of the scale, and a total sample of 911 nurse data from the Yangtze River Delta Regional Nursing Alliance Hospital was gathered. RESULTS: The Chinese version of NPDCC included 45 items, 5 factors (critical thinking skills, special diagnostic skills, general diagnostic skills, technical skills, and communication skills) were extracted from the analysis, which could explain the 68.289% of the total variance. The content validity index was 0.925. The Cronbach's α of the total NPDCC score was 0.978, and 0.884-0.945 for every factor. The split-half for the scale was 0.930, and every factor was 0.861-0.894. CONCLUSIONS: The Chinese version of NPDCC has excellent reliability and validity, and it is suitable to measure nurses' perceptions of disaster core competencies in China. The next step is to promote the application in a large scale.


Assuntos
COVID-19 , Desastres , China , Comparação Transcultural , Humanos , Percepção , Psicometria , Reprodutibilidade dos Testes , SARS-CoV-2 , Inquéritos e Questionários
8.
Opt Express ; 13(5): 1628-34, 2005 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-19495038

RESUMO

Near infrared broadband emission characteristics of bismuth-doped aluminophosphate glass have been investigated. Broad infrared emissions peaking at 1210nm, 1173nm and 1300nm were observed when the glass was pumped by 405nm laser diode (LD), 514nm Ar+ laser and 808nm LD, respectively. The full widths at half maximum (FWHMs) are 235nm, 207nm and 300nm for the emissions at 1210nm, 1173nm and 1300nm, respectively. Based on the energy matching conditions, it is suggested that the infrared emission may be ascribed to 3P1? 3P0 transition of Bi+. The broadband infrared luminescent characteristics of the glasses indicate that they are promising for broadband optical fiber amplifiers and tunable lasers.

9.
Opt Express ; 13(5): 1635-42, 2005 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-19495039

RESUMO

We report near infrared broadband emission of bismuth-doped barium-aluminum-borate glasses. The broadband emission covers 1.3microm window in optical telecommunication systems. And it possesses wide full width at half maximum (FWHM) of ~200nm and long lifetime as long as 350micros. The luminescent properties are quite sensitive to glass compositions and excitation wavelengths. Based on energy matching conditions, we suggest that the infrared emission may be ascribed to 3P1? 3P0 transition of Bi+. The broad infrared emission characteristics of this material indicate that it might be a promising candidate for broadband optical fiber amplifiers and tunable lasers.

10.
Opt Express ; 13(20): 7893-8, 2005 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-19498818

RESUMO

Visible upconversion luminescence was observed in Cr3+: Al2O3 crystal under focused femtosecond laser irradiation. The luminescence spectra show that the upconversion luminescence originates from the 2E-4A2 transition of Cr3+. The dependence of the fluorescence intensity of Cr3+ on the pump power reveals that a two-photon absorption process dominates in the conversion of infrared radiation to the visible emission. It is suggested that the simultaneous absorption of two infrared photons produces the population of upper excited states, which leads to the characteristic visible emission from 2E state of Cr3+.

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