Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
J Mass Spectrom ; 59(8): e5073, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38989767

RESUMEN

The fruits of Forsythia suspensa (F. suspensa) have been used as a traditional Chinese medicine for 2000 years. Currently, the quality control of F. suspensa strictly follows the instructions of Chinese Pharmacopeia, which mainly controls the content of forsythoside A, phillyrin, and volatile oil. In this study, air pressure MALDI mass spectrometry imaging (AP-MALDI MSI) was used to evaluate the quality of F. suspensa fruits and the distribution of dozens of active ingredients. The variation of active ingredients was measured for more than 30 batches of samples, regarding harvest time, cultivated environment, shelf-life, and habitat. Fifty-three active ingredients could be detected in F. suspensa fruits with AP-MALDI MSI. Seven active ingredients were upregulated, four ingredients downregulated, and 15 ingredients did not change in ripe fruits. A sharp variation of active ingredients in late September was observed for the Caochuan fruits harvested in 2019, which is closely related to the appearance of the ginger color of the pericarp under the microscope observation. The microscope observation is a reliable way to classify ripe and green fruits instead of outlook. Just considering forsythoside A and phillyrin, it is found that wild fruits are better than cultivated fruits, but cultivated fruits have high contents of other ingredients. The shelf-life of F. suspensa fruits is proposed to be 3 years, considering the 26 ingredients investigated. It was found that Luoning wild fruits are better than those from Caochuan with a new evaluation method. Mass spectrometry imaging is an easy, objective, and effective method to evaluate the quality of F. suspensa fruits.


Asunto(s)
Forsythia , Frutas , Glicósidos , Control de Calidad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Forsythia/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Frutas/química , Glicósidos/análisis , Glucósidos/análisis , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Aceites Volátiles/análisis , Aceites Volátiles/química
2.
J Chromatogr A ; 1722: 464846, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38579612

RESUMEN

In forensic science, glyphosate (GLYP) and glufosinate (GLUF), a class of non-selective broad-spectrum herbicides, have been frequently encountered in many fatal poisoning and suicide cases due to their widespread availability. Therefore, it is essential to develop an effective method for detecting these compounds. Some conventional methods, such as gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC-MS), have been reported to detect these compounds. However, these methods are not ideal for their time-consuming and non-sensitive feature. Herein, probe electrospray ionization (PESI) tandem mass spectrometry (MS/MS), a fast and sensitive technique, was applied for the determination of GLYP and GLUF in human blood, which can obtain analytical results within 0.5 min without derivatization and chromatographic separation. After protein precipitation of blood samples, the supernatant was mixed with isopropanol and ultra-pure water (1:1 v/v). Then, 8 µL of the mixture was introduced into the plastic sample plate for PESI-MS/MS analysis. The limits of detection (LODs) of the method were 0.50 µg/mL and 0.25 µg/mL for two analytes, and the limits of quantitation (LOQs) were both 1.00 µg/mL, which are higher than the concentration of reported poisoning and fatal cases. In the linear range of 1-500 µg/mL, the regression coefficients (r2) for GLYP and GLUF were over 0.99. The matrix effects ranged from 94.8 % to 119.5 %, and the biases were below 4.3 %. The recoveries ranged between 84.8 % and 107.4 %, and the biases were below 7.6 %. Meanwhile, the method was effectively utilized to detect and quantify the blood, urine, and other samples. Consequently, the results suggest that PESI-MS/MS is a straightforward, fast, and sensitive method for detecting GLUF and GLYP in forensics. In the future, PESI-MS/MS will become an indispensable technique for polar substances in grassroots units of public security where rapid detection is essential.


Asunto(s)
Aminobutiratos , Glicina , Glifosato , Herbicidas , Límite de Detección , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem , Humanos , Glicina/análogos & derivados , Glicina/sangre , Espectrometría de Masa por Ionización de Electrospray/métodos , Aminobutiratos/sangre , Espectrometría de Masas en Tándem/métodos , Herbicidas/sangre , Herbicidas/envenenamiento , Reproducibilidad de los Resultados
3.
J Mass Spectrom ; 57(6): e4831, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35562642

RESUMEN

Frozen section examination could provide pathological diagnosis for surgery of thyroid nodules, which is time-consuming, skill- and experience-dependent. This study developed a rapid classification method for thyroid nodules and machine learning. Total 69 tissues were collected including 43 nodules and 26 nodule-adjacent tissues. Intraoperative frozen section was first performed to give accurate diagnosis, and the rest frozen specimen were pretreated for probe electrospray ionization mass measurement. By multivariate analysis of mass scan data, a series compounds were found downregulated in the extraction solution of papillary thyroid carcinoma (PTC), but some were found upregulated by mass spectrometry imaging. m/z 758.5713 ([PC[34:2] + H]+ ), m/z 772.5845 ([PC[32:0] + K]+ ), and m/z 786.6037 ([PC[36:2] + H]+ ) were firstly identified as potential biomarkers for nodular goiter (NG). Machine learning was employed by means of support vector machine (SVM) and random forest (RF) algorithms. For classification of PTC from NG, SVM and RF algorithms exhibited the same performance and the concordance was 94.2% and 94.4% between prediction and pathological diagnosis with positive and negative mass dataset, respectively. For the classification of PTC from PTC adjacent tissues, SVM was better than RF and the concordance was 93.8% and 83.3% with positive and negative mass dataset, respectively. With the identified compounds as training features, the sensitivity and specificity are 87.5% and 88.9% for the test set. The developed method could also correctly predict the malignancy of one medullary thyroid carcinoma and one adenomatous goiter (benign). The diagnosis time is about 10 min for one specimen, and it is very promising for the intraoperative diagnosis of papillary thyroid carcinoma.


Asunto(s)
Neoplasias de la Tiroides , Nódulo Tiroideo , Humanos , Aprendizaje Automático , Espectrometría de Masa por Ionización de Electrospray , Cáncer Papilar Tiroideo/diagnóstico , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/patología , Nódulo Tiroideo/patología
4.
Zhongguo Zhong Yao Za Zhi ; 42(2): 370-377, 2017 Jan.
Artículo en Chino | MEDLINE | ID: mdl-28948746

RESUMEN

The methods of literature metrology and data mining were used to study the research topics and social network analysis of traditional Chinese medicine for constipation. The major Chinese databases were searched to include the research studies of traditional Chinese medicine for constipation. BICOMS analysis software was used to extract and collect the main information and produce co-occurrence Matrix; gCLUTO software was used for cluster analysis. Data analysis was conducted by using SPSS 19.0 software. The results showed that the number of studies on traditional Chinese medicine for constipation was constantly increased, with two literature volume peaks respectively in 2003 and 2006. Related studies have been published in 31 provinces, autonomous regions and municipalities have published, but the studies in developed areas were more than those in developing areas. There was little cooperation between research institutions and the authors, especially the cooperation between different areas. At present, the research field of Chinese medicine for constipation is divided into five research topics. In terms of specific traditional Chinese medicine, angelica sinensis is in the core position. The results showed regional imbalance in the number of studies on Chinese medicine treatment for constipation, as well as little cooperation between researchers and research institutions. The research topics mainly focused on the evaluation of clinical efficacy, but the research on optimizing the prescriptions was still not enough, so the future researchers shall pay more attention to the studies of constipation prescriptions with Angelica sinensis as the core herb.


Asunto(s)
Estreñimiento/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Angelica sinensis , Análisis por Conglomerados , Minería de Datos , Humanos , Medicina Tradicional China , Programas Informáticos
5.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 33(6): 558-563, 2017 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-29931908

RESUMEN

OBJECTIVE: To observe the therapeutic effects and mechanism of Dunhuang Liaofengxushouruo decoction (LXD) (Traditional Chinese Medicine) on chronic heart failure(CHF) in rats. METHODS: Forty-eight male Wistar rats were randomly divided into normal group(n=8):model group, captopril group and LXD(Traditional Chinese Medicine) high, medium and low dose group. Except the normal group, the rats were intravenous injected with adriamycin 2.5 mg/kg in one day for 6 weeks, the captopril rats were intragastric administrated by captopril 25 mg/kg, LXD high, medium and low dose groups were intragastric administrated by LXD of 80, 40, 20 g/kg for 6 consecutive weeks. The rats breathing, coat color, activity, body weight(BW) and time of exhaustive swimming were measured; Heart rate, mean arterial pressure (MAP), left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), maximal rate of left ventricular pressure (+dp/dtmax or -dp/dtmax)of each rat were examined by Power Lab. The levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were measured; The rats were sacrificed and hearts removed for separation of left and right ventricle, the antioxidant activity and ventricular mass index were measured, left ventricular myocardium was administrated by 4% paraformaldehyde, HE staining, morphological changes were observed under microscope. RESULTS: Body weight of each group decreased, and time of exhaustive swimming decreased after modeling (P<0.01). At 28 days after administration, BW in high and middle dose of LXD groups were increased and the swimming time of rats in LXD high dose group was increased (P<0.05).At 42 days, BW in all of LXD groups were increased and the exhaustive swimming time of high and middle dose of LXD were prolonged (P<0.05), MAP was decreased and LVSP, +dp/dtmax or -dp/dtmax were increased in LXD high and middle groups. The LVEDP was decreased in high dose of LXD group(P<0.05,P<0.01). The levels of creatine kinase (CK) and aspartate aminotransferase (AST) in middle and low dose of LXD groups were decreased(P<0.05,P<0.01), and the serum levels of IL-6, TNF-α and malondialdehyde (MDA) in serum in LXD high and middle dose groups were lower. The activities of superoxide dismutase (SOD) in serum were increased in all of LXD groups, and the LVMI and RVMI were decreased in high and middle dose of LXD groups(P<0.05,P<0.01). The pathological results showed that myocardial fiber arrangement and myocardial interstitial edema phenomenon were obviously improved in high dose of LXD group and CMD decreased. CONCLUSIONS: Therapeutic effect of LXD on CHF by doxorubicin-induced in rats is confirmed, the mechanisms are associated with improved hemodynamics and myocardial tissue.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Insuficiencia Cardíaca/tratamiento farmacológico , Corazón/efectos de los fármacos , Animales , Presión Sanguínea , Captopril/farmacología , Doxorrubicina , Frecuencia Cardíaca , Interleucina-6/sangre , Masculino , Malondialdehído/sangre , Miocardio , Ratas , Ratas Wistar , Superóxido Dismutasa/sangre , Factor de Necrosis Tumoral alfa/sangre
6.
ACS Appl Mater Interfaces ; 5(15): 6937-45, 2013 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-23808655

RESUMEN

Polyethylenimine (PEI)-impregnated resins with high CO2 adsorption capacity were successfully prepared in this study. The nonpolar resin HP20 was suitable for PEI loading to achieve high CO2 adsorption, and the optimal PEI loading was 50 wt %. On the basis of the pore-size distribution of the resin before and after PEI modification, it can be found that mesopores of <43 nm were mainly responsible for PEI loading and pores in the range of 43-68 nm were probably favorable for CO2 diffusion. The adsorbed amount of CO2 on HP20/PEI-50 decreased with increasing adsorption temperature because of the dominant role of exothermic reaction of CO2 adsorption. The adsorption of CO2 on the adsorbent was very fast, and sorption equilibrium was achieved within 6 min at 75 °C. HP20/PEI-50 almost kept a stable adsorption capacity for CO2 at concentrations of 15 vol % and 400 ppm in the consecutive adsorption-desorption cycles, and its adsorption capacity was 181 mg/g from pure CO2 and 99.3 mg/g from 400 ppm CO2 at 25 °C, higher than all PEI-modified materials reported. The high volume-based amount of CO2 adsorbed on HP20/PEI-50 (96.0 mg/cm(3) at 25 °C and 84.5 mg/cm(3) at 75 °C for pure CO2) is beneficial to reducing the required volume of the adsorption bed for CO2 capture. This spherical and stable HP20/PEI-50 adsorbent with high and fast CO2 adsorption exhibits a very promising application in CO2 capture from flue gas and ambient air.

7.
ChemSusChem ; 5(12): 2354-60, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23132775

RESUMEN

Cost-effective biomass-derived activated carbons with a high CO(2) adsorption capacity are attractive for carbon capture. Bamboo was found to be a suitable precursor for activated carbon preparation through KOH activation. The bamboo size in the range of 10-200 mesh had little effect on CO(2) adsorption, whereas the KOH/C mass ratio and activation temperature had a significant impact on CO(2) adsorption. The bamboo-derived activated carbon had a high adsorption capacity and excellent selectivity for CO(2) , and also the adsorption process was highly reversible. The adsorbed amount of CO(2) on the granular activated carbon was up to 7.0 mmol g(-1) at 273 K and 1 bar, which was higher than almost all carbon materials. The pore characteristics of activated carbons responsible for high CO(2) adsorption were fully investigated. Based on the analysis of narrow micropore size distribution of several activated carbons prepared under different conditions, a more accurate micropore range contributing to CO(2) adsorption was proposed. The volume of micropores in the range of 0.33-0.82 nm had a good linear relationship with CO(2) adsorption at 273 K and 1 bar, and the narrow micropores of about 0.55 nm produced the major contribution, which could be used to evaluate CO(2) adsorption on activated carbons.


Asunto(s)
Dióxido de Carbono/aislamiento & purificación , Carbón Orgánico/química , Sasa/química , Adsorción , Biomasa , Calor , Microscopía Electrónica de Rastreo , Porosidad , Propiedades de Superficie
8.
IEEE Trans Syst Man Cybern B Cybern ; 39(3): 658-71, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19188125

RESUMEN

Robust feature tracking is a requirement for many computer vision tasks such as indoor robot navigation. However, indoor scenes are characterized by poorly localizable features. As a result, indoor feature tracking without artificial markers is challenging and remains an attractive problem. We propose to solve this problem by constraining the locations of a large number of nondistinctive features by several planar homographies which are strategically computed using distinctive features. We experimentally show the need for multiple homographies and propose an illumination-invariant local-optimization scheme for motion refinement. The use of a large number of nondistinctive features within the constraints imposed by planar homographies allows us to gain robustness. Also, the lesser computation cost in estimating these nondistinctive features helps to maintain the efficiency of the proposed method. Our local-optimization scheme produces subpixel accurate feature motion. As a result, we are able to achieve robust and accurate feature tracking.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA