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1.
Phytopathology ; 114(1): 102-110, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37432065

RESUMO

Alfalfa Paraphoma root rot (APRR) (Paraphoma radicina) is a recently described alfalfa disease widely distributed in China, first reported in 2020. So far, the resistance levels of 30 alfalfa cultivars to APRR have been characterized; however, the resistance mechanisms among these cultivars remain unknown. In the present study, the alfalfa resistance mechanisms against APRR were investigated by studying the difference of P. radicina infecting susceptible (Gibraltar) and resistant (Magnum II) alfalfa cultivars under the light microscope and scanning electronic microscope. The conidial germination and germ tube growth in the root exudates of different resistant cultivars were also compared. The results revealed that conidial germination, germ tube development, and P. radicina penetration into root tissues of resistant plants were delayed. In susceptible and resistant cultivars, P. radicina infected roots by penetrating epidermal cells and the intercellular space between epidermal cells. During the infection process, germ tubes penetrated the root surface directly or formed appressoria. However, the penetration percentage on the susceptible cultivar was significantly higher than on the resistant cultivar, irrespective of the infection route. Moreover, disintegrated conidia and germ tubes were observed on resistant cultivar roots at 48 h postinoculation. The conidial germination and germ tube growth in root exudates of susceptible cultivars were significantly higher than in resistant cultivars. The current findings implied that the alfalfa resistance mechanism might be related to root exudates. These findings could provide insights into the alfalfa resistance mechanism following P. radicina infection.


Assuntos
Ascomicetos , Medicago sativa , Germinação , Doenças das Plantas
2.
Med Chem ; 16(1): 104-118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30398118

RESUMO

OBJECTIVE: Due to the incidence of resistance, a series of sulfonamide-derived 1,2,4- triazoles were synthesized and evaluated. METHOD: The novel sulfonamide-derived 1,2,4-triazoles were prepared starting from commercial acetaniline and chlorosulfonic acid by sulfonylation, aminolysis, N-alkylation and so on. The antimicrobial activity of the synthesized compounds were evaluated in vitro by two-fold serial dilution technique. RESULTS: In vitro antimicrobial evaluation found that 2-chlorobenzyl sulfonamide 1,2,4-triazole 7c exhibited excellent antibacterial activities against MRSA, B. subtilis, B. typhi and E. coli with MIC values of 0.02-0.16 µmol/mL, which were comparable or even better than Chloromycin. The preliminary mechanism suggested that compound 7c could effectively bind with DNA, and also it could bind with human microsomal heme through hydrogen bonds in molecular docking. Computational chemical studies were performed on compound 7c to understand the structural features that are essential for activity. Additionally, compound 7c could generate a small amount of reactive oxygen species (ROS). CONCLUSION: Compound 7c could serve as a potential clinical antimicrobial candidate.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Sulfonamidas/farmacologia , Triazóis/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Bacillus/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Saccharomyces cerevisiae/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Triazóis/síntese química , Triazóis/química
3.
Eur J Med Chem ; 136: 165-183, 2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28494254

RESUMO

A novel series of benzimidazole-incorporated sulfonamide analogues were designed and synthesized with an effort to overcome the increasing antibiotic resistance. Compound 5c gave potent activities against Gram-positive bacteria and fungi, and 2,4-dichlorobenzyl derivative 5g showed good activities against Gram-negative bacteria. Both of these two active molecules 5c and 5g could effectively intercalate into calf thymus DNA to form compound-DNA complex respectively, which might block DNA replication to exert their powerful antimicrobial activity. Molecular docking experiments suggested that compounds 5c and 5g could insert into base-pairs of DNA hexamer duplex by the formation of hydrogen bonds with guanine of DNA. The transportation behavior of these highly active compounds by human serum albumin (HSA) demonstrated that the electrostatic interactions played major roles in the strong association of active compounds with HSA, and which was also confirmed by the full geometry calculation optimizations.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Benzimidazóis/farmacologia , Desenho de Fármacos , Sulfonamidas/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Benzimidazóis/química , Bovinos , DNA/química , Relação Dose-Resposta a Droga , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Albumina Sérica/química , Relação Estrutura-Atividade , Sulfonamidas/química
4.
Zhong Yao Cai ; 36(9): 1454-6, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24620693

RESUMO

OBJECTIVE: To investigate the chemical constituents of the lichen plants Parmelia tinctorum and Parmelia nimandairana collected from Meng Mountain in Shandong province. METHODS: Various chromatographic techniques were used to isolate and purify the constituents and their structures were elucidated by means of spectral evidence and physiochemical properties. RESULTS: Four compounds were isolated from Parmelia tinctorum and identified as: lecanoric acid (I), evernic acid (II), ethyl orsellinate (III) and 3,5-dihydroxytoluene (IV). Two compounds were isolated from Parmelia nimandairana and identified as: usnic acid (V) and salazinic acid (VI). CONCLUSION: Compounds V and VI are isolated from Parmelia nimandairana for the first time.


Assuntos
Benzofuranos/isolamento & purificação , Lactonas/isolamento & purificação , Líquens/química , Salicilatos/isolamento & purificação , Benzofuranos/química , China , Cromatografia Líquida de Alta Pressão , Hidroxibenzoatos/química , Hidroxibenzoatos/isolamento & purificação , Lactonas/química , Líquens/classificação , Estrutura Molecular , Resorcinóis/química , Resorcinóis/isolamento & purificação , Salicilatos/química , Solventes/química
5.
J Chromatogr A ; 1265: 176-80, 2012 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-23062978

RESUMO

In this paper, we established a new on-line method using micelle to solvent stacking (MSS) technique combining with large amount sample electrokinetic stacking injection (LASEKSI) for the analysis of cationic molecules. In this MSS-LASEKSI, by modulating the integral EOF across the capillary, a equilibrium state was formed and can be maintained for a long time, leading to the continuous stacking of the analytes on the basis of MSS. Thereby, an extremely large amount sample was permitted to be injected into the capillary and then an improved enrichment fold can be achieved comparing with the each case. The variables affecting the performance of MSS-LASEKSI were investigated and discussed. Under the optimized conditions, 6.3 × 10(3)- and 6.4 × 10(2)-fold enrichment in peak heights upon normal CZE method (injected at 0.5 psi for 3 s) and number of plates of 2.9 × 10(6) and 6.5 × 10(5) were attained for berberine and theophylline, respectively. The developed method described here may provide prospects for exploiting a new concentration technique to achieve higher enrichment factor.


Assuntos
Eletroforese Capilar/métodos , Micelas , Solventes/química , Cátions
6.
J Chromatogr A ; 1233: 156-60, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22398383

RESUMO

Many reports have focused on the determination of hydroxyproline (Hyp) in blood plasma, urine sample, meat and meat products, however, there are few concerned with the Hyp assay in dairy products for food quality assurance up to now. In this paper, we described a sensitive and automated approach for the determination of Hyp in milk powder, liquid milk, milk drink and soymilk powder samples by micellar electrokinetic chromatography (MEKC) based on in-capillary derivatization for the first time. Under the optimal conditions, derivatization and separation procedure could be completed within 7 min and the detection limit for Hyp was 1.6±0.5 ng mL(-1). Comparing with the existing alternatives, the present method exhibited some relevant advantages, including full automation, satisfactory sensitivity, and short analysis time for Hyp assay in dairy products.


Assuntos
Cromatografia Capilar Eletrocinética Micelar/métodos , Laticínios/análise , Hidroxiprolina/análise , Espectrometria de Fluorescência/métodos , Lasers , Controle de Qualidade
7.
Midwifery ; 28(2): 222-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21419534

RESUMO

AIM: this study aimed to explore new parents' views and experiences during their transition to parenthood. BACKGROUND: in China the one-child birth policy may bring more stress and challenges for the new parents due to the lack of experience and greater expectations of their new role. China is also at a stage of rapid economic and social development which creates new conditions for parenthood. METHODS: a cross-sectional survey was conducted from February to September 2009 among 232 mothers and fathers, yielding a 83.6% response rate (n=194 couples). The questionnaire included: the Family Assessment Device-General Function Scale, the Family Resources Scale, the Family Adaptation Scale, and the Chinese Perceived Stress Scale. RESULTS: there were no significant differences between mothers' adaptation and fathers' adaptation during the postpartum period, as well as their perceived stress, family function and family resources (p>0.05). Method of childbirth was not related to adaptation. About 29% of variance in mothers' adaptation could be explained by satisfaction with the infant's gender (B=0.295, p<0.001), fathers' adaptation (B=0.236, p<0.001), and family resources (B=0.179, p=0.016). About 42% of variance in fathers' adaptation could be explained by mothers' adaptation (B=0.268, p<0.001), satisfaction with marriage (B=0.248, p=0.002), satisfaction with the infant's gender (B=0.209, p<0.007), and family resources (B=0.206, p=0.002). CONCLUSION: this study highlights the importance of family resources to family adaptation and antenatal and postnatal education programmes as part of family-centred care. The possible influences of culture and policies need to be considered by health-care professionals developing strategies to facilitate family adaptation to the early parenthood.


Assuntos
Adaptação Psicológica , Pai/psicologia , Mães/psicologia , Pais/psicologia , Período Pós-Parto/psicologia , China , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Gravidez , Estresse Psicológico , Inquéritos e Questionários
8.
J Nanosci Nanotechnol ; 11(12): 10387-95, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22408914

RESUMO

Guanidine group (Gnd) functionalized magnetic nanoparticles (Fe3O4@SiO2@NH2-Gnd) were synthesized and characterized in this work for the first time. The characterization of Fe3O4@SiO2@ NH2-Gnd nanoparticles was demonstrated by transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectra, vibration sample magnetometer, and zeta potential analyzer. The novel multifunctional nanoparticles were served as a solid-phase extraction sorbent for easy isolation and preconcentration of acidic protein from aqueous solution only using a magnet. Bovine serum albumin (BSA) was selected as a model protein and the main experimental parameters influencing the adsorption and desorption efficiency were investigated and optimized. Under the optimum conditions, the particles reached saturated adsorption within 20 min and exhibited significant specific recognition for the acidic proteins. Fifteen fold enrichment efficiency was achieved and the detection limits was 45 ng x mL(-1) for BSA by capillary electrophoresis (CE). The practical application of the novel nanoparticles as a sorbent for the isolation and preconcentration of acidic proteins from basic proteins was demonstrated by effective separation and enrichment of bovine serum albumin from lysozyme and cytochrome C mixture, which was assayed by CE.


Assuntos
Ácidos/química , Guanidina/química , Magnetismo , Nanopartículas , Soroalbumina Bovina/isolamento & purificação , Adsorção , Eletroforese Capilar , Microscopia Eletrônica de Transmissão , Soroalbumina Bovina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
9.
Coron Artery Dis ; 22(1): 87-91, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21169815

RESUMO

OBJECTIVES: To investigate the effects of loading dose of atorvastatin on periprocedural myocardial injury and inflammatory reaction in patients with non-ST segment elevation (NSTE) acute coronary syndromes (unstable angina or NSTE acute myocardial infarction). METHODS: A total of 81 patients with NSTE-acute coronary syndromes were randomly divided into the pretreatment with atorvastatin group [80 mg 12 h before percutaneous coronary intervention (PCI), with a further 40 mg preprocedure dose] (n=41) or the placebo group (n=40). The main end point was a 30-day incidence of major adverse cardiac events (cardiac death, nonfatal acute myocardial infarction, or revascularization with either PCI or coronary artery bypass grafting). Creatine kinase-MB, cardiac troponin I, and high-sensitivity C-reactive protein levels were measured at the baseline and at 8 and 24 h after the procedure. RESULTS: Major adverse cardiac events occurred in 2.4% of patients in the atorvastatin group and 22.5% of those in the placebo group (P=0.0161). This difference was mostly because of reduction in the incidence of myocardial infarction (2.4 vs. 20.0%; P=0.0307). Markers of the two groups were elevated after PCI; however, the higher values of creatine kinase-MB, cardiac troponin I, and high-sensitivity C-reactive protein in the atorvastatin treatment group were significantly lower than those in the placebo group (P<0.01). CONCLUSION: Short-term pretreatment with a high dose of atorvastatin significantly reduces procedural myocardial injury in early PCI.


Assuntos
Síndrome Coronariana Aguda/terapia , Angina Instável/terapia , Angioplastia Coronária com Balão/efeitos adversos , Ácidos Heptanoicos/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Infarto do Miocárdio/terapia , Pirróis/administração & dosagem , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/mortalidade , Idoso , Angina Instável/sangue , Angina Instável/mortalidade , Angioplastia Coronária com Balão/mortalidade , Atorvastatina , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Distribuição de Qui-Quadrado , China , Creatina Quinase Forma MB/sangue , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/prevenção & controle , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Prevenção Secundária , Fatores de Tempo , Resultado do Tratamento , Troponina I/sangue
10.
Chem Biodivers ; 6(5): 746-53, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19479840

RESUMO

Three novel fernane-type triterpenoids, lobarialides A-C (1-3, resp.), together with two known ones were isolated by antifungal bioassay-guided fractionation of the lichen Lobaria kurokawae. Their structures including configurations were established on the basis of extensive spectroscopic analyses, and that of 1 was confirmed by a single-crystal X-ray diffraction analysis. Antifungal tests of the five triterpenoids showed that the activity increased with the increment of the number of COO groups.


Assuntos
Antifúngicos/farmacologia , Ascomicetos/química , Líquens/química , Triterpenos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Testes de Sensibilidade Microbiana , Triterpenos/química , Triterpenos/isolamento & purificação , Difração de Raios X
11.
Zhong Yao Cai ; 30(6): 651-5, 2007 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-17918430

RESUMO

Six compounds have been isolated from the lichen plant Lobaria kurokawae and their structures were determined as ergosterol (1) , stictan-3beta, 22alpha-diol (2), retigeric acid B (5), retigeric acid A (6), ethyl orsellinate (3)and 3-O-methyl-1,2: 5,6-bis-O-(1 -mehtylethylidene)-d-chiro-inostiol (4) on the basis of spectral data(MS, 1H-NMR, 13C-NMR and 2D-NMR). Compounds 1-4 were isolated from this plant for the first time.


Assuntos
Medicamentos de Ervas Chinesas/análise , Ergosterol/análise , Líquens/química , Triterpenos/análise , Medicamentos de Ervas Chinesas/isolamento & purificação , Ergosterol/isolamento & purificação , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Triterpenos/isolamento & purificação
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