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1.
Pestic Biochem Physiol ; 202: 105913, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879317

RESUMO

Bacterial leaf blight, caused by Xanthomonas oryzae pv. oryzae (Xoo), poses a significant threat to rice cultivation across diverse regions. Growing concerns about pesticide resistance and environmental impact underscore the urgent necessity for eco-friendly biopesticides. Here, the complete genome sequence of Streptomyces albidoflavus strain ML27 revealed substantial antimicrobial activity and secondary metabolite production potential through genome mining. 3,4-dimethoxyphenol (purity 97%) was successfully isolated from the fermentation broth of S. albidoflavus strain ML27, exhibiting broad and pronounced inhibitory effects on the growth of seven different fungi and five tested bacteria. The efficacy of 3,4-dimethoxyphenol in controlling rice bacterial leaf blight was evaluated through pot tests, demonstrating substantial therapeutic (69.39%) and protective (84.53%) effects. Application of 3,4-dimethoxyphenol to Xoo resulted in cells displayed notable surface depressions, wrinkles, distortions, or even ruptures compared to their typical morphology. Transcriptome analysis revealed significant inhibition of membrane structures, protein synthesis and secretion, bacterial secretion system, two-component system, flagellar assembly, as well as various metabolic and biosynthetic pathways by 3,4-dimethoxyphenol. Notably, the down-regulation of the type III secretion system (T3SS) expression was a pivotal finding. Furthermore, validation via quantitative real-time polymerase chain reaction (qRT-PCR) analysis confirmed significant downregulation of 10 genes related to T3SS upon 3,4-dimethoxyphenol treatment. Based on these results, it is promising to develop 3,4-dimethoxyphenol as a novel biopesticide targeting the T3SS of Xoo for controlling bacterial leaf blight in rice.


Assuntos
Streptomyces , Xanthomonas , Xanthomonas/efeitos dos fármacos , Xanthomonas/genética , Streptomyces/genética , Streptomyces/metabolismo , Doenças das Plantas/microbiologia , Perfilação da Expressão Gênica , Oryza/microbiologia , Antibacterianos/farmacologia
2.
Public Health Nurs ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940530

RESUMO

OBJECTIVE: To explore their perceptions and attitudes toward condom use and the underlying reasons for the low usage frequency among Chinese older adults. METHODS: A qualitative study design utilizing interpretive phenomenological analysis was employed. Data were collected through field observation and face-to-face in-depth interviews among older adults aged 50 years or above and having engaged in sexual activities within the previous year. RESULTS: Three main themes emerged: perceiving unnecessary due to misconceptions and low awareness, interactive stereotypes rooted in sociocultural beliefs, and stigmatized social norms including gender inequity and economic unbalance. CONCLUSIONS: Tailored interventions focusing on addressing misconceptions, increasing awareness, and reducing culturally ingrained stereotypes and stigma surrounding condom use are essential to promote condom use among older adults in order to prevent HIV transmission in China.

3.
Pestic Biochem Physiol ; 195: 105534, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37666587

RESUMO

Ring rot induced by Botryosphaeria dothidea is a major cause of growth and postharvest losses in various fruits. There is an urgent need to develop green fungicides due to pesticide resistance and environmental pressure. Here, we demonstrated the efficacy of dictamnine (DIC, 4-methoxyfuro [2,3-ß] quinoline, purity 98%), a compound isolated from the stems and leaves of Clausena lansium, in effectively suppressing pear ring rot by inhibiting the mycelial growth of B. dothidea. The median effective concentration of DIC was 15.48 µg/mL. Application of DIC to B. dothidea resulted in structural disruption of the cell wall and plasma membrane, leading to mycelial deformation, breakage, and cell death. Transcriptome analysis revealed significant inhibition of the synthetic pathways for fungal cell wall and membrane components by DIC. Particularly, the expression of chitin synthase, a key enzyme of chitin synthesis, was prominently down-regulated. Moreover, the chitin content in DIC-treated B. dothidea mycelia exhibited a substantial dose-dependent reduction. Based on these results, it is promising to develop DIC as an antifungal pesticide for controlling ring rot disease in pear fruits. Our study provides new insights into the underlying mechanism through which DIC inhibits the mycelial growth of B. dothidea.


Assuntos
Pyrus , Quinolinas , Quitina
4.
Acta Radiol ; 63(4): 536-544, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33745294

RESUMO

BACKGROUND: Most commonly used diffusion-weighted imaging (DWI) models include intravoxel incoherent motion (IVIM), diffusion kurtosis imaging (DKI), stretched exponential model (SEM), and mono-exponential model (MEM). Previous studies of the four models were inconsistent on which model was more effective in distinguishing cervical cancer from normal cervical tissue. PURPOSE: To assess the performance of four DWI models in characterizing cervical cancer and normal cervical tissue. MATERIAL AND METHODS: Forty-seven women with suspected cervical carcinoma underwent DWI using eight b-values before treatment. Imaging parameters, calculated using IVIM, SEM, DKI, and MEM, were compared between cervical cancer and normal cervical tissue. The diagnostic performance of the models was evaluated using independent t-test, Mann-Whitney U test, receiver operating characteristic (ROC) curve analysis, and multivariate logistic regression analysis. RESULTS: All parameters except pseudo-diffusion coefficient (D*) differed significantly between cervical cancer and normal cervical tissue (P < 0.001). Through logistic regression analysis, all combined models showed a significant improvement in area under the ROC curve (AUC) compared to individual DWI parameters. The model with combined IVIM parameters had a larger AUC value compared to those of other combined models (P < 0.05). CONCLUSION: All four DWI models are useful for differentiating cervical cancer from normal cervical tissue and IVIM may be the optimal model.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Colo do Útero/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Plant Dis ; 2022 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35253487

RESUMO

Solanum muricatum is native to South America and well known for its sweet, attractive, nutritious fruits. S. muricatum has been cultivated in China since the 1980s and increasingly popular (Li et al. 2015). In November 2021, an unknown fruit rot was observed in Shilin County of Yunnan Province (24.77 °N, 103.28 °E). The incidence of this disease was about 16% of 500 postharvest S. muricatum fruits after 7 d in storage room (25°C, 90% relative humidity). The initial symptoms were small brown spots on the fruit surface, which gradually expanded into irregular brown or black lesions, and gray-white mold developed in the center of the lesions, eventually the fruit turned rot. To isolate the pathogen, ten fruits with typical symptoms were collected and surface-sterilized with 75% ethanol for 45 s. Small fragments (5 × 5 mm) from the margin of lesions on fruit were disinfected with 1% sodium hypochlorite for 60 s, washed three times with sterile water then transferred to potato dextrose agar (PDA), and incubated at 28 ± 1℃ for 3 days (Li et al. 2022). Two fungal isolates with the same morphology were obtained and purified by single-spore isolation method. The colony was covered with thick fluffy aerial mycelia and the center was dark brown or black with white margins. Conidia were brown, pyriform or ellipsoid, with 1 to 3 longitudinal and 2 to 6 transverse septa, 15.12 to 34.01 × 6.90 to 12.73 µm (21.22 × 9.69 µm on average, n=50) in size. These morphological characteristics were consistent with Alternaria alternata (Li et al. 2015; Xiang et al. 2021; Alberto. 1992). For molecular identification, genomic DNA was extracted from a representative isolate, and primers ITS1/ITS4 (Gardes et al. 1993), TEF-F/TEF-R (Lawrence et al. 2013), Alt-F/Alt-R (Hong et al. 2005), GPD-F/GPD-R (Berbee et al. 1999) and EPG-F/EPG-R (Peever et al. 2004) were used to amplify the internal transcribed spacer (ITS), translation elongation factor 1-alpha (TEF), Alternaria major allergen (Alt a1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and endo-polygalacturonase (endoPG), respectively. The obtained DNA sequences (ITS: OM049821; TEF: OM069656; Alt a1: OM069655; GAPDH: OM069654 and endoPG: OM069653) showed over 99% homology with that of A. alternata (GenBank Accession No. MN856355.1 (565/573 bp); MN258023.1 (267/267 bp); KY923227.1 (491/501 bp); LC131645.1 (608/609 bp) and MN698284.1 (452/454 bp)). A phylogenetic tree based on the combined ITS, TEF, Alt a1, GAPDH, and endoPG sequences using the maximum likelihood methods with Kimura 2-parameter model, bootstrap nodal support for 1000 replicates in MEGA7.0 (Li et al. 2019) revealed that the isolate was assigned to A. alternata. To confirm pathogenicity, 10 µL spore suspension (1.0 × 106 conidia/ml) obtained from 7-day-old PDA cultures of each isolate were inoculated on 15 needle-wounded and 15 non-wounded surface-disinfected fruits, respectively. Healthy fruits were inoculated with sterile water as controls and the experiment was repeated 3 times. All fruit were incubated at 25 ± 1℃, 90% relative humidity. After 7 days, all the wounded and non-wounded fruit inoculated with A. alternata showed similar symptoms to those observed on the previously fruits, while the control fruits remained healthy. The same pathogen was again isolated from the inoculated fruits, thus Koch's postulates were fulfilled. A. alternata causing fruit rot of Prunus avium and Mangifera indica in China were reported in previous studies (Ahmad et al. 2020; Liu et al. 2019). As far as we know, this is the first report of postharvest fruit rot on S. muricatum caused by A. alternata in southwest China. This work provides a basis for the development of control strategies of the disease in the future.

6.
Plant Dis ; 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35380465

RESUMO

Begonia lanternaria Irmsch., an ornamental plant endemic in China, which is commonly used in landscape and interior decoration. In March 2021, an estimated 30% B. lanternaria plants were observed with anthracnose-like symptoms at a botanical garden conservation greenhouse in Mengla County of Yunnan Province (21.91° N, 101.21°E). Initially, small black spots developed on the disease leaves, which gradually expanded into irregular necrotic lesions surrounded by a yellowish halo, eventually turned wilting and defoliating. Twenty diseased leaves were collected and surface-disinfested with 75% ethanol for 30 s. Small fragments (5 × 5 mm) from the margin of lesions were disinfected with 1% NaClO for 120 s, washed with sterile water three times, and cultured on potato dextrose agar (PDA) at 28 ± 1℃. After 3 days single spores from four fungal colonies with identical morphology were isolated. Colonies on PDA were 70-75 mm diam in 7 d (7.5-10.6 mm/d), with dense white to gray-white mycelia attached with brown to black-brown acervulus. The underside of the culture was yellow to yellowish-brown concentric circle. Conidia were single-celled, hyaline, straight to slightly curved, cylindrical, 12.88 to 16.66 × 6.25 to 7.97 µm (av=14.65 µm × 7.22 µm, n=50) in size. For molecular identification, genomic DNA was extracted from a representative isolate, and the internal transcribed spacer, glyceraldehyde-3-phosphate dehydrogenase, calmodulin gene, ß-tublin, actin, and chitin synthase 1 genes were amplified with ITS1/ITS4 (Gardes et al, 1993), GDF/GDR (Templeton et al, 1992), CL1C/CL2C (Li et al, 2018), Bt2a/Bt2b (Prihastuti et al, 2009), ACT-512F/ACT-783R and CHS-79F/CHS-345R (Carbone et al, 1999) primers, respectively. The obtained DNA sequences showed over 99% homology with Colletotrichum karsti (GenBank Accession No. ITS: NR144790; GAPDH: KX578772; CAL: KY039988; TUB2: KX578804; ACT: LC412408; CHS1: KU251855), and the results of sequences were deposited into GenBank with accession No. MZ496954 (522/522 bp), MZ504978 (238/238 bp), MZ504979 (737/737 bp), MZ504982 (472/472 bp), MZ504981 (273/273 bp), MZ504980 (282/284 bp). The phylogenetic tree combined with ITS-ACT-GAPDH-CHS 1-CAL-TUB2 concatenated sequences using the maximum likelihood methods showed that the isolate was C. karsti. To confirm pathogenicity, Koch's postulates were conducted on intact plants, 10 µl spore suspension (1.0 × 106 conidia/ml) of each of four isolates (7-day-old culture on PDA) was inoculated on 15 wounded with a sterilized needle or non-wounded healthy living leaves, and 15 wounded leaves were inoculated with sterile water as controls. All leaves were incubated at 28 ± 1°C and 90% relative humidity (12 h/12 h light/dark). After 5 days, all wounded leaves inoculated with C. karsti showed symptoms similar to those previously observed, while the control and non-wounded leaves remained healthy. Colletotrichum karsti was re-isolated from inoculated leaves. C. karsti was previously reported to cause disease on Nicotiana tabacum L. (Zhao et al, 2020), Stylosanthes guianensis (Jia et al, 2017) and Fatsia japonica (Xu et al, 2020) in China. To our knowledge, this is the first report of C. karsti causing anthracnose of B. lanternaria Irmsch. in China. This disease reduces the ornamental and economic value of B. lanternaria Irmsch., and this work will provide a basis for the prevention and treatment of the disease in the future.

7.
Fetal Pediatr Pathol ; 41(1): 77-86, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32479132

RESUMO

Objective: We determined the prevalence and relationship of glycoprotein B (gB), glycoprotein N (gN), and glycoprotein H (gH) genotypes of cytomegalovirus (CMV) in CMV-associated thrombocytopenia (CAP). Methods: CMV gB, gN, and gH strains were determined by nested PCR and restriction length polymorphism from 24 CAP and 20 asymptomatic CMV infected infants. Results: The order of prevalence was gB1 (70.8%,17/24), gN4 (45.8%,11/24) and gH2 (54.2%,13/24). There was a greater prevalence of gB1(75.0%,15/20), gN4(50.0%,10/20) and gN2 (35.0%,7/20) in moderate to severe infection (p = 0.014 and p = 0.003). By logistic regression, gH2 (p = 0.031) had an elevated risk of thrombocytopenia. Reduced risks of thrombocytopenia were associated with gB2 (p = 0.020), gN1 (p = 0.018) and gN3 (p = 0.008). The most virulent were gB1 (p = 0.033) and gN2 (p = 0.038). Conclusions: There may be a potential association between the gH2 genotype of CMV and infantile thrombocytopenia.


Assuntos
Infecções por Citomegalovirus , Trombocitopenia , Citomegalovirus/genética , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/epidemiologia , Feminino , Genótipo , Humanos , Lactente , Polimorfismo de Fragmento de Restrição , Gravidez , Trombocitopenia/genética
8.
Molecules ; 26(17)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34500738

RESUMO

The inhibition of α-glucosidase is a clinical strategy for the treatment of type 2 diabetes mellitus (T2DM), and many natural plant ingredients have been reported to be effective in alleviating hyperglycemia by inhibiting α-glucosidase. In this study, the α-glucosidase inhibitory activity of fisetin extracted from Cotinus coggygria Scop. was evaluated in vitro. The results showed that fisetin exhibited strong inhibitory activity with an IC50 value of 4.099 × 10-4 mM. Enzyme kinetic analysis revealed that fisetin is a non-competitive inhibitor of α-glucosidase, with an inhibition constant value of 0.01065 ± 0.003255 mM. Moreover, fluorescence spectrometric measurements indicated the presence of only one binding site between fisetin and α-glucosidase, with a binding constant (lgKa) of 5.896 L·mol-1. Further molecular docking studies were performed to evaluate the interaction of fisetin with several residues close to the inactive site of α-glucosidase. These studies showed that the structure of the complex was maintained by Pi-Sigma and Pi-Pi stacked interactions. These findings illustrate that fisetin extracted from Cotinus coggygria Scop. is a promising therapeutic agent for the treatment of T2DM.


Assuntos
Flavonóis/química , Flavonóis/farmacologia , alfa-Glucosidases/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Simulação de Acoplamento Molecular
9.
J Cell Physiol ; 234(10): 18361-18370, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30887511

RESUMO

Long noncoding RNA maternally expressed gene 3 (lncRNA-MEG3) is an important regulator in multiple biological functions. However, lncRNA-MEG3's function in cattle growth and regulatory mechanism on bovine skeletal muscle development has not yet been well studied. In this project, we first investigated lncRNA-MEG3's expression profile and detected that it was highly expressed in bovine skeletal muscle tissue and its RNA level was kept increasingly during the early phase of bovine primary myoblast differentiation. Using luciferase reporter assays, we identified the lncRNA-MEG3 core promoter containing putative transcription factor binding site for myocyte enhancer factor 2C (MEF2C). Interestingly, we found that LncRNA-MEG3 could significantly upregulate and downregulate myosin heavy chain ( MHC), myogenin ( MyoG), and MEF2C through overexpression and RNAi strategies, respectively. Using luciferase reporter assays, we also verified lncRNA-MEG3 as a miR-135 sponge. Overexpression of miR-135 markedly inhibited the wild type of lncRNA-MEG3, but not the mutant lncRNA-MEG3 reporter. The luciferase activity of miR-135 sensor could be rescued by lncRNA-MEG3 via competing for miRNA-135. In addition, the luciferase activity of MEF2C was significantly upregulated by the wild type of lncRNA-MEG3. This study, for the first time, revealed that lncRNA-MEG3 could promote bovine skeletal muscle differentiation via interacting with miRNA-135 and MEF2C. The results were valuable for further studies and applications of lncRNA related roles in beef molecular breeding.


Assuntos
Diferenciação Celular/genética , MicroRNAs/genética , Mioblastos/fisiologia , RNA Longo não Codificante/genética , Animais , Apoptose/genética , Bovinos , Diferenciação Celular/fisiologia , Proliferação de Células/genética , Regulação para Baixo/genética , Fatores de Transcrição MEF2/genética , Desenvolvimento Muscular/genética , Músculo Esquelético/fisiologia , Interferência de RNA/fisiologia , Ativação Transcricional/genética , Regulação para Cima/genética
10.
Molecules ; 24(17)2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31466274

RESUMO

Clausena lansium Lour. Skeels (Rutaceae) is widely distributed in South China and has historically been used as a traditional medicine in local healthcare systems. Although the characteristic components (carbazole alkaloids and coumarins) of C. lansium have been found to possess a wide variety of biological activities, little attention has been paid toward the other components of this plant. In the current study, phytochemical analysis of isolates from a water-soluble stem and leaf extract of C. lansium led to the identification of 12 compounds, including five aromatic glycosides, four sesquiterpene glycosides, two dihydrofuranocoumarin glycosides, and one adenosine. All compounds were isolated for the first time from the genus Clausena, including a new aromatic glycoside (1), a new dihydrofuranocoumarin glycoside (6), and two new sesquiterpene glycosides (8 and 9). The phytochemical structures of the isolates were elucidated using spectroscopic analyses including NMR and MS. The existence of these compounds demonstrates the taxonomic significance of C. lansium in the genus Clausena and suggests that some glycosides from this plant probably play a role in the anticancer activity of C. lansium to some extent.


Assuntos
Clausena/química , Compostos Fitoquímicos/análise , Estrutura Molecular , Especificidade de Órgãos , Compostos Fitoquímicos/química , Folhas de Planta/química , Caules de Planta/química
11.
J Sep Sci ; 39(19): 3700-3708, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27601197

RESUMO

Yonkenafil is a promising drug for treatment of male erectile dysfunction. Previous studies showed that the piperazine-N,N'-deethylation metabolite, piperazine-N-deethylation metabolite, and piperazine-N-deethylation-N,N'-deethylation metabolite were the major metabolites of yonkenafil after extensive metabolism. We developed a sensitive and selective method for the simultaneous quantification of yonkenafil and its major metabolites using high-throughput liquid chromatography with tandem mass spectrometry. Analytes and internal standard were extracted from a small quantity of plasma (50 µL) using liquid-liquid extraction with diethyl ether/dichloromethane (60:40, v/v), and the baseline separation was achieved on Zorbax SB-C18 column using ammonia/water/methanol (0.2:20:80, v/v/v) as the mobile phase. The assay was performed with an electrospray positive ionization mass spectrometry through the multiple-reaction monitoring mode within 2 min. Calibration curve of the method was linear within the range of 1.00-1000 ng/mL for all the analytes with the intra- and interday precisions of 4.0-5.2 and 4.0-5.3% for yonkenafil, 3.1-4.9 and 3.1-5.2% for the piperazine-N,N'-deethylation metabolite, 4.8-6.8 and 4.8-7.3% for the piperazine-N-deethylation metabolite, and 2.9-6.1 and 5.4-6.3% for the piperazine-N-deethylation-N,N'-deethylation metabolite, respectively. The recoveries were above 90% with low matrix effects. The validated assay was successfully applied to support a preclinical pharmacokinetic study in six rats using a single oral dose of yonkenafil (8 mg/kg).


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Pirimidinonas/sangue , Pirróis/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Estrutura Molecular , Plasma/química , Pirimidinonas/química , Pirimidinonas/metabolismo , Pirróis/química , Pirróis/metabolismo , Ratos , Ratos Wistar , Sensibilidade e Especificidade
12.
J Sep Sci ; 38(21): 3803-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26315362

RESUMO

Lobaplatin, consisting of two diastereoisomers, is a third-generation platinum antineoplastic agent that has shown encouraging anticancer activity in a variety of tumor types. To investigate any stereospecificity in the pharmacokinetics of lobaplatin, a novel, simple, rapid and sensitive supercritical fluid chromatography with tandem mass spectrometry method was developed for the simultaneous quantitation of lobaplatin diastereoisomers in rat plasma. After a simple protein precipitation with methanol, the analytes and dexpantoprazole (internal standard) were chromatographed on an Acquity UPC(2) system with a Chiralcel OZ-RH column using a mobile phase consisting of carbon dioxide and methanol (65:35, v/v) at 40°C over 6 min. The assay was linear over a concentration range of 25-15,000 ng/mL for both diastereoisomers using 100 µL of rat plasma for sample preparation. The lower limit of quantification was 25 ng/mL for both compounds, which was sufficient to detect the diastereoisomers in the incurred samples within this study. Intra- and inter-day precisions were below 11.8% and the accuracies were below 4.5%. The validated method was successfully applied to a pharmacokinetic study after an intravenous administration of 7.6 mg/kg lobaplatin to rats. There was no apparent stereospecificity in the pharmacokinetics between the two diastereoisomers of lobaplatin.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Ciclobutanos/sangue , Compostos Organoplatínicos/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Área Sob a Curva , Ciclobutanos/farmacocinética , Meia-Vida , Limite de Detecção , Compostos Organoplatínicos/farmacocinética , Ratos , Reprodutibilidade dos Testes , Estereoisomerismo
13.
Org Biomol Chem ; 12(41): 8336-45, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25216100

RESUMO

A new class of 9-amino-(9-deoxy)cinchona alkaloid-derived chiral phase-transfer catalysts bearing amino groups was developed by using known cinchona alkaloids as the starting materials. Due to the transformation of the 9-hydroxyl group into a 9-amino functional group, the catalytic performances were significantly improved in comparison with the corresponding first generation phase-transfer catalysts, and excellent yields (92-99%) and high enantioselectivities (87-96% ee) were achieved in the benchmark asymmetric α-alkylation of glycine Schiff base. Based on the special contribution of the amino group to the high yield and enantioselectivity, the possible catalytic mechanism was conjectured.


Assuntos
Alcaloides de Cinchona/química , Alcaloides Indólicos/química , Quinuclidinas/química , Catálise , Alcaloides de Cinchona/síntese química , Alcaloides Indólicos/síntese química , Estrutura Molecular , Transição de Fase , Quinuclidinas/síntese química , Estereoisomerismo
14.
Yao Xue Xue Bao ; 49(12): 1689-93, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25920198

RESUMO

A new phenethanol, (2'R)-4-(2', 3'-dihydroxy-3'-methyl-butanoxy)-phenethanol (1), along with other eleven known benzene derivatives (2-12) were isolated from the roots, stems and leaves of Clausena excavata (Rutaceae). Compounds 3 and 4 are new natural products, and compounds 5-8, 10-12 were isolated from C. excavata for the first time. Their structures were elucidated on the basis of MS, 1D and 2D NMR spectroscopic analyses including HSQC, COSY and HMBC experiments. 1 was tested for its cytotoxicities against A549, HeLa and BGC-823 cancer cell lines, and antimicrobial activities against Candida albicans and Staphylococcus aureus. The results showed that 1 did not exhibit cytotoxic and antimicrobial activities.


Assuntos
Derivados de Benzeno/química , Clausena/química , Candida albicans/efeitos dos fármacos , Linhagem Celular Tumoral , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , Staphylococcus aureus/efeitos dos fármacos
15.
Zhongguo Zhong Yao Za Zhi ; 39(9): 1620-4, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25095372

RESUMO

To investigate monoterpenes and sesquiterpenes of the stems and leaves of Clausena excavata, an AcOEt fraction of the methanol extract was subjected on column chromatographies including silica gel and RP-18, as well as preparative HPLC. The structures of compounds isolated were identified on the basis of spectroscopic data as excamonoterpene (1), (6R, 9S)-9, 10-dihydroxy-4-megastigmen-3-one (2), (3R, 6R, 7E) -3-hydroxy-4, 7-megastigmadien-9-one (3), (3S) -3-hydroxy-7, 8-dihydro-beta-ionone (4), (3S, 5R, 6S) -3-hydroxy-5,6-epoxy-beta-ionone (5), (6R, 9R) -9-hydroxy-4-megastigmen-3-one (6), (3S, SR) -dihydroxy-6, 7-megstigmadien-9-one(7), (-)-loliolide(8), caryolane-1, 9alpha-diol(9) and 2, 6-dihydroxyhumula-3 (12), 7 (13), 9(E)-triene (10), were isolated from the stems and leaves of C. excavata. Compound 1 is a new monoterpene, named as excamonoterpene. Compounds 2-10 were isolated from this plant for the first time.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Clausena/química , Monoterpenos/análise , Sesquiterpenos/análise , Espectroscopia de Ressonância Magnética , Metanol/química , Estrutura Molecular , Monoterpenos/química , Folhas de Planta/química , Caules de Planta/química , Sesquiterpenos/química , Espectrometria de Massas por Ionização por Electrospray
16.
Front Public Health ; 12: 1259634, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384881

RESUMO

Background: Menstrual symptoms were the common complaints of international female students during the acculturation period, and the symptoms negatively affected the daily life and school performance of those women. The present study aimed to evaluate the effectiveness of the traditional Chinese Baduanjin exercise on reducing menstrual symptoms for international female students studying in China during the acculturation period. Methods: We conducted a randomized controlled trial among 62 international female students who suffered menstrual symptoms during the first 6 months after arriving in China. The study was carried out at three campuses of the two largest universities in the capital of a province in south-central China from March to October 2021. After screening, participants were randomly assigned to a control or intervention group. The intervention group engaged in 24 weeks of Baduanjin exercise for at least 30 min per day. The menstrual symptoms, sociocultural adaptation, perceived stress, and sleep quality were evaluated at baseline, the 12th week, and the 24th week. The chi-square test or Fisher's exact test, paired sample t-test, and multivariate analysis of variance (MANOVA)were adopted to analyze the data using SPSS 25.0. Results: Totally, 62 participants were enrolled in this study from 30 countries. Their mean age was 27.87 ± 5.58 years. None of the participants reported an adverse event. The results of the MANOVA test showed that the traditional Chinese Baduanjin exercise reduced the total score of MSQ among international female students (intervention: 47.83 ± 8.71 vs. control: 65.12 ± 16.86; F = 19.49, P < 0.01). In addition, the results of the MANOVA indicated statistically significant decreases in scores for the two subscales of MSQ: premenstrual symptoms (intervention: 17.07 ± 3.33 vs. control: 28.42 ± 7.56; F = 44.70, P < 0.01)and menstrual pain (16.03 ± 4.53 vs. 19.58 ± 5.14; F = 6.50, P < 0.05). Moreover, the results showed that traditional Chinese Baduanjin exercise reduced the scores of the sociocultural adaptation level, the perceived stress level, and sleep quality and improved the blood progesterone hormone and blood estrogen hormone. Conclusion: Regular Baduanjin exercise is a safe, acceptable, and effective form of exercise to promote international female students' menstrual health, reduce stress levels, and improve sleep quality. Trial registration: www.chictr.org.cn, Chinese Clinical Trial Registry: ChiCTR2300072376.


Assuntos
Terapia por Exercício , Exercício Físico , Humanos , Feminino , Adulto Jovem , Adulto , China , Terapia por Exercício/métodos , Estudantes , Hormônios
17.
Chem Biodivers ; 10(7): 1317-21, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23847076

RESUMO

One new carbazole alkaloid, excavatine A (1), and two additional new alkaloids, excavatine B (2) and excavatine C (3), were isolated from the stems and leaves of Clausena excavata Burm.f. (Rutaceae). Their structures were determined on the basis of detailed spectroscopic analyses, especially 2D-NMR and HR-EI-MS data. Compounds 1-3 were tested for their cytotoxic activities against A549, HeLa, and BGC-823 cancer cell lines, and for their antimicrobial activities against Candida albicans and Staphylococcus aureus. Only 1 exhibited cytotoxicity against A549 and HeLa cell lines with the IC50 values of 5.25 and 1.91 µg/ml, respectively.


Assuntos
Alcaloides/química , Anti-Infecciosos/química , Anti-Infecciosos/toxicidade , Carbazóis/química , Clausena/química , Alcaloides/isolamento & purificação , Alcaloides/toxicidade , Anti-Infecciosos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Carbazóis/isolamento & purificação , Carbazóis/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Folhas de Planta/química , Caules de Planta/química , Staphylococcus aureus/efeitos dos fármacos
18.
J Asian Nat Prod Res ; 15(3): 215-20, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23327112

RESUMO

Two new coumarins, clauexcavatins A (1) and B (2), along with seven known ones (3-9), were isolated from the roots of Clausena excavata Burm. f. (Rutaceae). Their structures were elucidated on the basis of spectral data.


Assuntos
Clausena/química , Cumarínicos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Carbazóis/química , Carbazóis/isolamento & purificação , Cumarínicos/química , Medicamentos de Ervas Chinesas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química
19.
Pharmazie ; 68(5): 333-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23802430

RESUMO

This study aimed to clarify the rationality of herbaceous compatibility of a rhubarb peony decoction (DaHuang-Mu-Dan-Tang, RPD) by comparing the pharmacokinetics of aloe-emodin, rhein and emodin in rats' plasma after oral administration of RPD and rhubarb extract. A rapid, sensitive LC-MS method was developed and validated for the determination of the plasma concentrations of the three analytes after oral administration RPD and rhubarb extract. The developed method was successfully applied to a pharmacokinetic study of aloe-emodin, rhein and emodin in rats' plasma after oral administration. Compared with administration of single rhubarb, the C(max) of rhein in RPD was decreased significantly (p < 0.05). Meanwhile, the T1/2 of aloe-emodin and emodin were increased significantly (p < 0.05) after administration of RPD. In addition, the T(max) of rhein and emodin were also increased significantly (p < 0.05) in RPD. These results indicated that the absorption of rhein in rats was suppressed after oral administration RPD. Moreover, The time for rhein and emodin to reach the peak concentration was delayed and the elimination of aloe-emodin and emodin was also postponed in RPD. This study could provide a meaningful basis for evaluating the clinical application of traditional Chinese medicine in terms of pharmacokinetics.


Assuntos
Aloe/química , Antraquinonas/farmacocinética , Catárticos/farmacocinética , Paeonia/química , Rheum/química , Animais , Antraquinonas/análise , Área Sob a Curva , Calibragem , Catárticos/análise , Cromatografia Líquida de Alta Pressão , Modelos Lineares , Masculino , Espectrometria de Massas , Organização e Administração , Extratos Vegetais/farmacocinética , Controle de Qualidade , Ratos , Ratos Sprague-Dawley , Padrões de Referência , Reprodutibilidade dos Testes
20.
Zhongguo Zhong Yao Za Zhi ; 38(1): 60-3, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23596878

RESUMO

OBJECTIVE: To study the chemical constituents of the unmatured fruits of Citrus aurantium. METHOD: The AcOEt fraction of the methanol extracts of the unmatured fruits of C. aurantium were subjected on column chromatographies including silica gel, RP-18 and HPLC. Compound structures isolated were determined on the basis of spectroscopic data. RESULT: Three compounds were isolated from the unmatured fruits of C. aurantium, which were identified as citrauranoside (1), limonexin (2) and limonin (3). CONCLUSION: Compound 1 is a new chroman glycoside derivative, named as citrauranoside.


Assuntos
Cromanos/química , Citrus/química , Medicamentos de Ervas Chinesas/química , Frutas/química , Glicosídeos/química , Extratos Vegetais/química , Cromanos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Glicosídeos/isolamento & purificação , Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/isolamento & purificação
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