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1.
BMC Womens Health ; 24(1): 482, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223612

RESUMO

BACKGROUND: Cervical cancer (CC) and breast cancer (BC) threaten women's well-being, influenced by health-related stigma and a lack of reliable information, which can cause late diagnosis and early death. ChatGPT is likely to become a key source of health information, although quality concerns could also influence health-seeking behaviours. METHODS: This cross-sectional online survey compared ChatGPT's responses to five physicians specializing in mammography and five specializing in gynaecology. Twenty frequently asked questions about CC and BC were asked on 26th and 29th of April, 2023. A panel of seven experts assessed the accuracy, consistency, and relevance of ChatGPT's responses using a 7-point Likert scale. Responses were analyzed for readability, reliability, and efficiency. ChatGPT's responses were synthesized, and findings are presented as a radar chart. RESULTS: ChatGPT had an accuracy score of 7.0 (range: 6.6-7.0) for CC and BC questions, surpassing the highest-scoring physicians (P < 0.05). ChatGPT took an average of 13.6 s (range: 7.6-24.0) to answer each of the 20 questions presented. Readability was comparable to that of experts and physicians involved, but ChatGPT generated more extended responses compared to physicians. The consistency of repeated answers was 5.2 (range: 3.4-6.7). With different contexts combined, the overall ChatGPT relevance score was 6.5 (range: 4.8-7.0). Radar plot analysis indicated comparably good accuracy, efficiency, and to a certain extent, relevance. However, there were apparent inconsistencies, and the reliability and readability be considered inadequate. CONCLUSIONS: ChatGPT shows promise as an initial source of information for CC and BC. ChatGPT is also highly functional and appears to be superior to physicians, and aligns with expert consensus, although there is room for improvement in readability, reliability, and consistency. Future efforts should focus on developing advanced ChatGPT models explicitly designed to improve medical practice and for those with concerns about symptoms.


Assuntos
Neoplasias da Mama , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias da Mama/psicologia , Estudos Transversais , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/psicologia , Inquéritos e Questionários , Reprodutibilidade dos Testes , Internet , Adulto , Comportamento de Busca de Informação , Mamografia/psicologia
2.
BMC Cancer ; 23(1): 952, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37814233

RESUMO

BACKGROUND: Mammographic density (MD) is a strong risk factor for breast cancer. We aimed to evaluate the association between MD and breast cancer related risk factors among average-risk women in rural China. METHODS: This is a population-based screening study. 12518 women aged 45-64 years with complete MD data from three maternal and childcare hospitals in China were included in the final analysis. ORs and 95%CIs were estimated using generalized logit model by comparing each higher MD (BI-RADS b, c, d) to the lowest group (BI-RADS a). The cumulative logistic regression model was used to estimate the ORtrend (95%CI) and Ptrend by treating MD as an ordinal variable. RESULTS: Older age (ORtrend = 0.81, 95%CI: 0.79-0.81, per 2-year increase), higher BMI (ORtrend = 0.73, 95%CI: 0.71-0.75, per 2 kg/m2), more births (ORtrend = 0.47, 95%CI: 0.41-0.54, 3 + vs. 0-1), postmenopausal status (ORtrend = 0.42, 95%CI: 0.38-0.46) were associated with lower MD. For parous women, longer duration of breastfeeding was found to be associated with higher MD when adjusting for study site, age, BMI, and age of first full-term birth (ORtrend = 1.53, 95%CI: 1.27-1.85, 25 + months vs. no breastfeeding; ORtrend = 1.45, 95%CI: 1.20-1.75, 19-24 months vs. no breastfeeding), however, the association became non-significant when adjusting all covariates. Associations between examined risk factors and MD were similar in premenopausal and postmenopausal women except for level of education and oral hormone drug usage. Higher education was only found to be associated with an increased proportion of dense breasts in postmenopausal women (ORtrend = 1.08, 95%CI: 1.02-1.15). Premenopausal women who ever used oral hormone drug were less likely to have dense breasts, though the difference was marginally significant (OR = 0.54, P = 0.045). In postmenopausal women, we also found the proportion of dense breasts increased with age at menopause (ORtrend = 1.31, 95%CI: 1.21-1.43). CONCLUSIONS: In Chinese women with average risk for breast cancer, we found MD was associated with age, BMI, menopausal status, lactation, and age at menopausal. This finding may help to understand the etiology of breast cancer and have implications for breast cancer prevention in China.


Assuntos
Densidade da Mama , Neoplasias da Mama , Feminino , Humanos , Lactente , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Mamografia , Fatores de Risco , China/epidemiologia , Hormônios , Mama/diagnóstico por imagem
3.
J Sep Sci ; 46(19): e2300238, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37548129

RESUMO

Gynostemma pentaphyllum (Thunb.) Makino represents the popular health food and supplemental product with broad pharmacological activities. The highly polar glycosides, including flavonoids and saponins, are major effective active components that contain diverse sugar positions and quantities, which result in diverse chemical polarities, making it challenging to separate and isolate these components. The present work described the rapid and efficient linear gradient counter-current chromatography to preparatively separate glycosides from aboveground parts of G. pentaphyllum. Besides, the ethyl acetate and n-butanol binary mobile phases were achieved through adjusting associated proportions. Six glycosides, including quercetin-3-O-neohesperidoside (1), kaempferol-3-O-robinobioside (2), kaempferol-3-O-neohesperidoside (3), gypenoside LVI (4), ginsenoside Rb3 (5), and gypenoside XLVI (6), were isolated at the purities greater than 98%. Moreover, electrospray ionization mass spectrometry and nuclear magnetic resonance tandem mass spectrometry were conducted for structural identification. According to our findings, the established linear gradient counter-current chromatography was an efficient approach to separate the highly polar glycosides from aboveground parts of G. pentaphyllum. Our proposed strategy can be used to separate active compounds from other complex natural products.

4.
J Sep Sci ; 46(16): e2300053, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37376800

RESUMO

In this work, the preparative separation of quinolyridine alkaloids from seeds of T. lanceolata by conventional and pH-zone-refining counter-current chromatography. Traditional counter-current chromatography separation was performed by a flow-rate changing strategy with a solvent system of ethyl acetate-n-butanol-water (1:9:10, v/v) and 200 mg sample loading. Meanwhile, the pH-zone-refining mode was adopted for separating 2.0 g crude alkaloid extracts with the chloroform-methanol-water (4:3:3, v/v) solvent system using the stationary and mobile phases of 40 mM hydrochloric acid and 10 mM triethylamine. Finally, six compounds, including N-formylcytisine (two conformers) (1), N-acetycytisine (two conformers) (2), (-)-cytisine (3), 13-ß-hydroxylthermopsine (4), N-methylcytisine (5), and thermopsine (6) were successfully obtained in the two counter-current chromatography modes with the purities over 96.5%. Moreover, we adopted nuclear magnetic resonance and mass spectrometry for structural characterization. Based on the obtained findings, the pH-zone-refining mode was the efficient method to separate quinolyridine alkaloids relative to the traditional mode.


Assuntos
Alcaloides , Extratos Vegetais , Extratos Vegetais/química , Distribuição Contracorrente/métodos , Concentração de Íons de Hidrogênio , Cromatografia Líquida de Alta Pressão/métodos , Alcaloides/análise , Solventes/química , Água , Sementes/química
5.
J Sep Sci ; 46(9): e2300046, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36853146

RESUMO

As a famous health food, roots of Panax quinquefolium L. possessed immune regulation and enhancement of the central nervous system, in which ginsenosides are the main active component with different numbers and positions of sugars, causing different chemical polarities with a challenge for the separation and isolation. In this study, a fast and effective bilinear gradient counter-current chromatography was proposed for preparative isolation ginsenosides with a broad partition coefficient range from roots of Panax quinquefolium L. In terms of the established method, the mobile phases comprising n-butanol and ethyl acetate were achieved by adjusting the proportion. Coupled with the preparative HPLC, eleven main ginsenosides were successfully separated, including ginsenoside Rg1 (1), Re (2), acetyl ginsenoside Rg1 (3), Rb1 (4), Rc (5), Rg2 (6), Rb3 (7), quinquefolium R1 (8), Rd (9), gypenoside X VII (10) and notoginsenoside Fd (11), with purities exceeding 95% according to the HPLC results. Tandem mass spectrometry and electrospray ionization mass spectrometry were adopted for recognizing the isolated compound architectures. Our study suggests that linear gradient counter-current chromatography effectively separates the broad partition coefficient range of ginsenosides compounds from the roots of Panax quinquefolium L. In addition, it can apply to active compound isolation from other complicated natural products.


Assuntos
Ginsenosídeos , Panax , Ginsenosídeos/química , Cromatografia Líquida de Alta Pressão/métodos , Panax/química , Distribuição Contracorrente/métodos , Raízes de Plantas/química
6.
J Sep Sci ; 46(10): e2300042, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36939191

RESUMO

Cyperus rotundus L. has been extensively used in ancient medication for the treatment of different disorders worldwide, in which sesquiterpenes are the most representative components. In this study, sesquiterpenes were effectively purified by two-dimensional counter-current chromatography in combination with continuous injection and inner-recycling mode with a solvent system of n-hexane/ethyl acetate/methanol/water (1:0.2:1:0.2, v/v/v/v). For one-dimension separation, continuous injection mode was used with three times injection and the inner-recycling mode was adopted for the separation of two mixtures for two-dimensional separation. Finally, four sesquiterpenoids, including scariodione (1), cyperenoic acid (2), scariodione (3), and α-cyperone (4), were obtained with purities over 98%. Mass spectrometry and nuclear magnetic resonance were applied to identify their structures. The results from the anti-inflammation effect with zebrafish demonstrated that cyperenoic acid exhibited stronger anti-inflammation activity. Molecular docking results suggested that cyperenoic acid possessed lower binding energies -9.4545 kcal/mol with 1CX2 to form formed hydrogen bond interaction with ARG120. In general, all the obtained findings proved that the strong anti-inflammation capacity of cyperenoic acid can have the potential of being adopted for treating diseases resulting from inflammation.


Assuntos
Cyperus , Sesquiterpenos , Animais , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Cyperus/química , Distribuição Contracorrente/métodos , Rizoma , Peixe-Zebra , Anti-Inflamatórios
7.
J Sep Sci ; 46(20): e2300306, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37654052

RESUMO

Bergenia ciliata (haw.) Sternb, the renowned pharmaceutical plant in Jammu and Kashmir of Pakistan, is widely applied in treating different illnesses including diabetes, diarrhea, and vomiting. This work employed an efficient one-step inner-recycling counter-current chromatography for preparative separating and purifying compounds with similar partition coefficients from the rhizome of Bergenia ciliate (haw.). Five compounds, including quercetin rhamnodiglucoside (1), quercetin-3-O-rutinoside (2), bergenine (3), kaempferol (4), and palmatic acid (5), were successfully separated using the optimized biphasic solvent system that contained ter-butylmetylether/n-butanol/acetonitrile/water (2:2:1:5, v/v) with the purities over 98%. Mass spectrometry and nuclear magnetic resonance were conducted for structural identification. As a result, our proposed strategy might be applied in separating compounds with similar partition coefficients, which was advantageous with regard to the less solvent and time consumption, and the increased number of theoretical plates.


Assuntos
Distribuição Contracorrente , Plantas Medicinais , Distribuição Contracorrente/métodos , Extratos Vegetais/análise , Rizoma/química , Solventes/análise , Cromatografia Líquida de Alta Pressão
8.
J Med Internet Res ; 25: e43832, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36862499

RESUMO

BACKGROUND: A number of publications have demonstrated that deep learning (DL) algorithms matched or outperformed clinicians in image-based cancer diagnostics, but these algorithms are frequently considered as opponents rather than partners. Despite the clinicians-in-the-loop DL approach having great potential, no study has systematically quantified the diagnostic accuracy of clinicians with and without the assistance of DL in image-based cancer identification. OBJECTIVE: We systematically quantified the diagnostic accuracy of clinicians with and without the assistance of DL in image-based cancer identification. METHODS: PubMed, Embase, IEEEXplore, and the Cochrane Library were searched for studies published between January 1, 2012, and December 7, 2021. Any type of study design was permitted that focused on comparing unassisted clinicians and DL-assisted clinicians in cancer identification using medical imaging. Studies using medical waveform-data graphics material and those investigating image segmentation rather than classification were excluded. Studies providing binary diagnostic accuracy data and contingency tables were included for further meta-analysis. Two subgroups were defined and analyzed, including cancer type and imaging modality. RESULTS: In total, 9796 studies were identified, of which 48 were deemed eligible for systematic review. Twenty-five of these studies made comparisons between unassisted clinicians and DL-assisted clinicians and provided sufficient data for statistical synthesis. We found a pooled sensitivity of 83% (95% CI 80%-86%) for unassisted clinicians and 88% (95% CI 86%-90%) for DL-assisted clinicians. Pooled specificity was 86% (95% CI 83%-88%) for unassisted clinicians and 88% (95% CI 85%-90%) for DL-assisted clinicians. The pooled sensitivity and specificity values for DL-assisted clinicians were higher than for unassisted clinicians, at ratios of 1.07 (95% CI 1.05-1.09) and 1.03 (95% CI 1.02-1.05), respectively. Similar diagnostic performance by DL-assisted clinicians was also observed across the predefined subgroups. CONCLUSIONS: The diagnostic performance of DL-assisted clinicians appears better than unassisted clinicians in image-based cancer identification. However, caution should be exercised, because the evidence provided in the reviewed studies does not cover all the minutiae involved in real-world clinical practice. Combining qualitative insights from clinical practice with data-science approaches may improve DL-assisted practice, although further research is required. TRIAL REGISTRATION: PROSPERO CRD42021281372; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=281372.


Assuntos
Aprendizado Profundo , Neoplasias , Humanos , Neoplasias/diagnóstico por imagem , Algoritmos , Ciência de Dados
10.
J Sep Sci ; 45(11): 1856-1865, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35338696

RESUMO

Paeonia lactiflora Pall., one of the most famous classical herbal medicine, has been used to treat diseases for over 1200 years. In this research, the functional ingredients were purified by online-switch two-dimensional high-speed counter-current chromatography combined with inner-recycling and continuous injection mode. The antioxidant activity was evaluated by investigating the 2,2'-azobis (2-amidinopropane) dihydrochloride-induced oxidant damage in vitro and confirmed through molecular docking. n-Butanol/ethyl acetate/water (2:3:5, v/v) solvent system was used for the first-dimensional separation and optimized the sample loading. Two pure compounds and a polyphenol-enriched fraction were separated. The polyphenol-enriched fraction was separated with a solvent system n-hexane/ethyl acetate/methanol/water (2:8:4:6, v/v) with continuous injection mode. Five compounds were successfully separated, including gallic acid (1), methyl gallate (2), albiflorin (3), paeoniflorin (4), and ethyl gallate (5). Their structures were identified by mass spectrometry and NMR spectroscopy. The results from the antioxidant effect showed that albiflorin had stronger antioxidant activity. Molecular docking results indicated that the affinity energy of the identified compounds ranged from -3.79 to -8.22 kcal/mol and albiflorin showed the lowest affinity energy. Overall, all those findings suggested that the strong antioxidant capacity of albiflorin can be potentially used for the treatment of diseases caused by oxidation.


Assuntos
Paeonia , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Distribuição Contracorrente/métodos , Simulação de Acoplamento Molecular , Paeonia/química , Polifenóis , Solventes , Água
11.
Phytochem Anal ; 33(8): 1198-1204, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36028334

RESUMO

INTRODUCTION: Chaenomeles, including Chaenomeles speciosa (ZP), Chaenomeles sinensis (GP), Chaenomeles tibetica (XZ), and Chaenomeles japonica (RB), has been widely used as food in China for thousands of years. However, only ZP, was recorded to be the authentic medicinal Chaenomeles. Therefore, the rapid and accurate method for the authenticity identification of Chaenomeles species is urgently needed. OBJECTIVE: To develop a method for rapid differentiation of Chaenomeles species. METHODS: The visual volatile components fingerprints based on headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) combined with chemometric analysis, including principal component analysis (PCA), linear discriminant analysis (LDA) and partial least-squares discriminant analysis (PLS-DA), were utilised for the authentication of Chaenomeles species. RESULTS: The visual volatile components fingerprints by the GC-IMS intuitively showed the distribution features of the volatile components for different Chaenomeles samples. The LDA and PLS-DA models successfully discriminated Chaenomeles species with original discrimination accuracy of 100%. Fifteen volatile compounds (VOCs) (peaks 9, 12, 13, 19, 23, 24, 35, 48, 57, 65, 67, 76, 79, 80, 83) were selected as the potential species-specific markers of Chaenomeles via variable importance of projection (VIP > 1.2) and one-way analysis of variance (P < 0.05). CONCLUSIONS: This study showed that the visual volatile components fingerprints by HS-GC-IMS combined with chemometric analysis is a meaningful method in the Chaenomeles species authentication.


Assuntos
Rosaceae , Compostos Orgânicos Voláteis , Espectrometria de Mobilidade Iônica/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise , Quimiometria
12.
Breast Cancer Res Treat ; 181(3): 589-597, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32338323

RESUMO

PURPOSE: As an adjunct to mammography, ultrasound can improve the detection of breast cancer in women with dense breasts. We aimed to evaluate the diagnostic performance of automated breast ultrasound system (ABUS) and handheld ultrasound (HHUS) in Chinese women with dense breasts, both in combination with mammography and separately. METHODS: This is a cross-sectional multicenter clinical research study. Nine hundred and thirty-seven women with dense breasts underwent ABUS, HHUS, and mammography at one of five tertiary-care hospitals. The diagnostic performance of ABUS and HHUS was evaluated in combination with mammography, or separately in women with mammography-negative dense breasts. The agreement between ABUS and HHUS in breast cancer detection was also assessed. RESULTS: The sensitivity of the combination of ABUS or HHUS with mammography was 99.1% (219/221), and the specificities were 86.9% (622/716) and 84.9% (608/716), respectively. The area under the curve was 0.93 for ABUS combined with mammography and 0.92 for that of HHUS combined with mammography. Statistically significant agreement between ABUS and HHUS in breast cancer detection was observed (percent agreement = 0.94, κ = 0.85). The incremental cancer detection rate in mammography-negative dense breasts was 42.8 per 1000 ultrasound examinations. CONCLUSIONS: Both ABUS and HHUS as adjuncts to mammography can significantly improve the breast cancer detection rate in women with dense breasts, and there is a strong correlation between them. Given the high prevalence of dense breasts and the multiple advantages of ABUS over HHUS, such as less operator dependence and reproducibility, ABUS showed great potential for use in breast cancer early detection, especially in resource-limited areas.


Assuntos
Densidade da Mama , Neoplasias da Mama/diagnóstico , Detecção Precoce de Câncer/métodos , Processamento de Imagem Assistida por Computador/métodos , Mamografia/métodos , Ultrassonografia Mamária/métodos , Idoso , Automação , Neoplasias da Mama/diagnóstico por imagem , Estudos Transversais , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Prognóstico
13.
J Sep Sci ; 42(16): 2621-2627, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31166086

RESUMO

Toddalia asiatica (Linn.) Lam. is a medical plant traditionally used to treat coughs, fevers, and various diseases. Alkaloids are the main active ingredients in Toddalia asiatica (Linn.) Lam., but traditional methods for screening and separation are complex and labor-intensive. In this work, an efficient strategy was developed to rapidly screen, identify, and separate neuraminidase inhibitors from Toddalia asiatica (Linn.) Lam. Ultrafiltration, high performance liquid chromatography, and time-of-flight mass spectrometry were employed for rapid screening and identification of neuraminidase inhibitors. A two-phase solvent system comprising n-hexane/ethyl acetate/methanol/water (5:5:3:7, v/v) was then selected for separation by high-speed counter-current chromatography. A sample loading of 200 mg and a stepwise flow rate were achieved by increasing the flow rate from 2 to 4 mL/min after 4 h. Three main fluoroquinoline alkaloids (haplopine, skimmianine, and 5-methoxydictamnine) along with two coumarins were obtained via one-step separation and their structures were determined by mass spectrometry and nuclear magnetic resonance. In vitro assays revealed skimmianine with half-maximal inhibitory concentration of 16.2 ± 0.7 µmol/L was selected as the potential highest neuraminidase inhibitor. The results suggest that ultrafiltration high performance liquid chromatography-mass spectrometry combined with high-speed counter-current chromatography is efficient for the screening and isolation of neuraminidase inhibitors from complex natural products.


Assuntos
Inibidores Enzimáticos/análise , Inibidores Enzimáticos/isolamento & purificação , Neuraminidase/antagonistas & inibidores , Extratos Vegetais/química , Raízes de Plantas/química , Rutaceae/química , Alcaloides/antagonistas & inibidores , Alcaloides/metabolismo , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Inibidores Enzimáticos/farmacologia , Estrutura Molecular , Neuraminidase/metabolismo , Extratos Vegetais/farmacologia
14.
Molecules ; 24(3)2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30754616

RESUMO

Seven diterpene lactones, andrographolide (1), isoandrographolide (2), neo-andrographolide (3), 14-deoxy-11,12-didehydroandrographolide (4), 14-deoxyandrographiside (5), 14-deoxy-11,12-didehydroandrographiside (6), 3,14-dideoxyandrographolide (10), and three flavones, andrographidine C (7), andrographidine A (8), 5-hydroxy-7,8-dimethoxyflavanone (9) have been successfully and efficiently isolated from A. paniculata using an off-line two dimensional (2D) high-speed counter-current chromatography (HSCCC) method for the first time. For the first dimension HSCCC separation, petroleum ether-ethyl acetate-methanol-water 3:7:5:5 (v/v) was employed to isolate 14.4 mg of compound 1, 3.1 mg of compound 2, 7.8 mg of compound 3, and 18.0 mg of compound 4 from 200 mg of the A. paniculata extract. For the second dimension HSCCC separation, petroleum ether-ethyl acetate-methanol-water 2:8:1:9 (v/v) and 5:5:6:4 (v/v) were employed to isolate the collected fractions ranged from 55 to 79 min and the flow out fraction, respectively, which led to 5.1 mg of compound 5, 4.4 mg of compound 6, 2.4 mg of compound 7, 3.3 mg of compound 8, 4.0 mg of compound 9, 7.0 mg of compound 10. The structures of these diterpene lactones and flavones were elucidated by extensive spectroscopic methods.


Assuntos
Andrographis/química , Diterpenos/isolamento & purificação , Flavonas/isolamento & purificação , Lactonas/isolamento & purificação , Cromatografia Líquida , Distribuição Contracorrente , Diterpenos/química , Flavonas/química , Lactonas/química , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
15.
Anal Bioanal Chem ; 409(30): 7087-7096, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29026954

RESUMO

We describe a solid-phase extraction adsorbent based on molecularly imprinted polymers (MIPs), prepared with use of a mimic template. The MIPs were used for the selective extraction and determination of three chlorogenic acids as combined quality markers for Lonicera japonica and Lianhua qingwen granules. The morphologies and surface groups of the MIPs were assessed by scanning electron microscopy, Brunauer-Emmett-Teller surface area analysis, and Fourier transform infrared spectroscopy. The adsorption isotherms, kinetics, and selectivity of the MIPs were systematically compared with those of non-molecularly imprinted polymers. The MIPs showed high selectivity toward three structurally similar chlorogenic acids (chlorogenic acid, cryptochlorogenic acid, and neochlorogenic acid). A procedure using molecularly imprinted solid-phase extraction coupled with high-performance liquid chromatography was established for the determination of three chlorogenic acids from Lonicera japonica and Lianhua qingwen granules. The recoveries of the chlorogenic acids ranged from 93.1% to 101.4%. The limits of detection and limits of quantification for the three chlorogenic acids were 0.003 mg g-1 and 0.01 mg g-1, respectively. The newly developed method is thus a promising technique for the enrichment and determination of chlorogenic acids from herbal medicines. Graphical Abstract Mimic molecularly imprinted polymers for the selective extraction of chlorogenic acids.


Assuntos
Ácido Clorogênico/química , Medicamentos de Ervas Chinesas/química , Lonicera/química , Polímeros/química , Adsorção , Impressão Molecular , Estrutura Molecular , Controle de Qualidade
16.
Molecules ; 23(1)2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29286331

RESUMO

Diaphragma juglandis fructus contains various bioactive constituents. Fourteen compounds were isolated from Diaphragma juglandis fructus by preparative high performance liquid chromatography (pre-HPLC) and high-speed counter-current chromatography (HSCCC). Their structures were identified by nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS). Compounds (+)-dehydrovomifoliol (12), (6R,9R)-9-hydroxymegastigman-4-en-3-one (13) and (6R,9S)-9-hydroxymegastigman-4-en-3-one (14) are found from Juglans regia L. for the first time. Compounds dihydrophaseic acid (2), blumenol B (3) and (4S)-4-hydroxy-1-tetralone (11) are isolated from Diaphragma juglandis fructus for the first time. The anti-inflammatory effects of isolated compounds were evaluated by an in vitro model of lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Compounds gallic acid (1), ethyl gallate (9) and (+)-dehydrovomifoliol (12) exhibited inhibitory activity on the nitric oxide production of RAW 264.7 at a concentration of 25 µM. The result indicated that the combination HSCCC with pre-HPLC is an effective way for compound separation and purification. And Diaphragma juglandis fructus constituents have the potential for the treatment of inflammatory-related diseases.


Assuntos
Acetatos/química , Juglandaceae/química , Óxido Nítrico/biossíntese , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Lipopolissacarídeos , Camundongos , Células RAW 264.7
17.
Molecules ; 22(5)2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28486427

RESUMO

In this work, flavonoid fraction from the leaves of Crataegus pinnatifida was separated into its seven main constituents using a combination of HSCCC coupled with pre-HPLC. In the first step, the total flavonoid extract was subjected to HSCCC with a two-solvent system of chloroform/methanol/water/n-butanol (4:3:2:1.5, v/v), yielding four pure compounds, namely (-)-epicatechin (1), quercetin-3-O-(2,6-di-α-l-rhamnopyranosyl)-ß-d-galactopyranoside (2), 4''-O-glucosylvitexin (3) and 2''-O-rhamnosylvitexin (4) as well as a mixture of three further flavonoids. An extrusion mode was used to rapidly separate quercetin-3-O-(2,6-di-α-l-rhamnopyranosyl)-ß-d-galactopyranoside with a big KD-value. In the second step, the mixture that resulted from HSCCC was separated by pre-HPLC, resulting in three pure compounds including: vitexin (5), hyperoside (6) and isoquercitrin (7). The purities of the isolated compounds were established to be over 98%, as determined by HPLC. The structures of these seven flavonoids were elucidated by ESI-MS and NMR spectroscopic analyses.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Distribuição Contracorrente/métodos , Crataegus/química , Flavonoides/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Apigenina/isolamento & purificação , Catequina/isolamento & purificação , Distribuição Contracorrente/instrumentação , Flavonoides/classificação , Glicosídeos/isolamento & purificação , Quercetina/análogos & derivados , Quercetina/isolamento & purificação , Solventes
18.
J Sep Sci ; 39(11): 2097-104, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27061885

RESUMO

We put forward an efficient strategy based on bioassay guidance for the rapid screening, identification, and purification of the neuraminidase inhibitors from traditional Chinese medicines, and apply to the discovery of anti-influenza components from Lithospermiun erythrorhizon Sieb.et Zucc. Ultrafiltration with high-performance liquid chromatography and electrospray ionization time-of-flight mass spectrometry was employed for the rapid screening and preliminarily identification of anti-influenza components from Zicao. Semipreparative high-performance liquid chromatography was used for the rapid separation and purification of the target compounds. NMR spectroscopy, mass spectrometry, and UV spectroscopy were used for further structural identification, and the activity of the compounds was verified by in vitro assay. Five compounds were found to have neuraminidase inhibitory activity by this method. Subsequently, the five compounds were separated by semipreparative high-performance liquid chromatography with the purity over 98% for all of them by high-performance liquid chromatography test. Combined with the NMR spectroscopy, mass spectrometry, and UV spectroscopy data, they were identified as alkannin, acetylalkannin, isobutyrylalkannin, ß,ß-dimethylacryloylalkannin and isovalerylalkannin. The in vitro assay showed that all five compounds had good neuraminidase inhibitory activities. These results suggested that the method is highly efficient, and it can provide platform and methodology supports for the rapid discovery of anti-influenza active ingredients from complex Chinese herbal medicines.


Assuntos
Inibidores Enzimáticos/farmacologia , Lithospermum/química , Neuraminidase/antagonistas & inibidores , Cromatografia Líquida de Alta Pressão , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Humanos , Estrutura Molecular , Neuraminidase/metabolismo , Espectrometria de Massas por Ionização por Electrospray
19.
J Nat Prod ; 77(2): 234-42, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24547740

RESUMO

Fourteen new dammarane-type triterpenoids (1-14) and 11 known analogues were isolated from the stem bark of Dysoxylum binecteriferum. The absolute configurations were established by comparison with the literature or by Mo2(OAc)4-induced electronic circular dichroism data. All isolates were evaluated for their cytotoxicities against three human cancer cell lines as well as their inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells. Compounds 4 and 8 displayed moderate cytotoxicities against HepG2 with IC50 values of 6.5 and 8.0 µM, respectively.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Meliaceae/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Medicamentos de Ervas Chinesas/química , Células Hep G2 , Humanos , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Casca de Planta/química , Triterpenos/química , Damaranos
20.
Huan Jing Ke Xue ; 45(5): 2548-2557, 2024 May 08.
Artigo em Zh | MEDLINE | ID: mdl-38629520

RESUMO

A total of 18 metal elements in ambient PM2.5 in Zhengzhou were continuously determined using an online heavy metal observation instrument in January and April, 2021, and the changes in element concentrations were analyzed. Metal elements were traced via enrichment factors, positive matrix factorization (PMF), and a characteristic radar chart. The US EPA health risk assessment model was used to assess the health risks of heavy metals, and the backward trajectory method and the concentration-weighted trajectory (CWT) method were used to evaluate the potential source regions of health risks. The results showed that the element concentrations were higher in spring, and the sum of Fe, Ca, Si, and Al concentrations accounted for 89.8% and 87.5% of the total element concentrations in winter and spring, respectively. Cd was enriched significantly, which was related to human activities. The concentrations of Pb, Se, Zn, Ni, Sb, and K in winter and Cr, Ni, Fe, Mn, V, Ba, Ca, K, Si, and Al in spring increased with the increasing pollution level. The results of PMF and the characteristic radar chart showed that the main sources of metal elements in winter and spring were industry, crust, motor vehicles, and mixed combustion, with industry and mixed combustion pollution occurring more often in winter and crust pollution occurring more often in spring. Significant non-carcinogenic risks existed in both winter and spring with more severe health risks in winter, and Mn caused significant non-carcinogenic risks. The health risks in winter were mainly influenced by Zhengzhou and surrounding cities and long-distance transport in the northwest, and the health risks in spring were mainly influenced by Zhengzhou and surrounding cities.


Assuntos
Poluentes Atmosféricos , Metais Pesados , Humanos , Poluentes Atmosféricos/análise , Material Particulado/análise , Monitoramento Ambiental , Metais Pesados/análise , Medição de Risco , China
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