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1.
Yao Xue Xue Bao ; 49(8): 1169-74, 2014 Aug.
Artículo en Zh | MEDLINE | ID: mdl-25322560

RESUMEN

The preliminary metabolic profile of total diterpene acid (TDA) isolated from Pseudolarix kaempferi was investigated by using in vivo and in vitro tests. Pseudolaric acid C2 (PC2) was identified as the predominant metabolite in plasma, urine, bile and feces after both oral and intravenous administrations to rats using HPLC-UV and HPLC-ESI/MS(n), and demethoxydeacetoxypseudolaric acid B (DDPB), a metabolite proposed to be the glucoside of PC2 (PC2G), as well as pseudolaric acid C (PC), pseudolaric acid A (PA), pseudolaric acid A O-beta-D glucopyranoside (PAG), pseudolaric acid B O-beta-D glucopyranoside (PBG) and deacetylpseudolaric acid A (DPA) originated from TDA could also be detected. It was demonstrated by tests that the metabolism of TDA is independent of intestinal microflora, and neither of pepsin and trypsin is in charge of metabolism of TDA, TDA is also stable in both pH environments of gastric tract and intestinal tract. The metabolites of TDA in whole blood in vitro incubation were found to be PC2, DDPB and PC2G, which demonstrated that the metabolic reaction of TDA in vivo is mainly occurred in blood and contributed to be the hydrolysis of plasma esterase to ester bond, as well as the glucosylation reaction. These results clarified the metabolic pathway of TDA for the first time, which is of great significance to the in vivo active form and acting mechanism research of P. kaempferi.


Asunto(s)
Diterpenos/metabolismo , Pinaceae/química , Animales , Cromatografía Líquida de Alta Presión , Glucósidos/metabolismo , Hidrólisis , Espectrometría de Masas , Redes y Vías Metabólicas , Ratas
2.
PLoS One ; 19(5): e0302588, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38748740

RESUMEN

Hebi is located in the northern part of China's Henan Province and is a typical receiving area for China's South-to-North Water Diversion Project. The assessment of habitat quality and water yield over a long time series is important for evaluating the stability of ecosystem services in Hebi and other receiving areas and for maintaining ecological security and promoting sustainable development. This paper aims to evaluate and dynamically analyse habitat quality and water yield in Hebi, and analyses the characteristics of changes in spatial and temporal patterns of land cover types, habitat quality and water yield in Hebi over the past 20 years, using 2000, 2005, 2010, 2015 and 2020 as horizontal years. The results indicate that: (1) During the study period, the overall land use type in Hebi City has been constantly changing, with the most significant conversion from arable land to other land types; combined with its landscape pattern index, Hebi City has a general characteristic of significant landscape fragmentation and complexity in land use. (2) Habitat quality in Hebi shows an overall trend towards better development, with water availability decreasing and then increasing; the zoning of ecosystem services in Hebi is divided into three classes: superior, good and general, with the area covered by the superior and general classes expanding year by year. (3) Correlation analysis by SPSS software shows that the correlation between habitat quality and landscape pattern index is greater than the correlation between habitat quality and climate change. Additionally, the correlation between water availability and climate change is greater than the correlation between water availability and landscape pattern index.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , China , Conservación de los Recursos Naturales/métodos , Abastecimiento de Agua , Agua , Monitoreo del Ambiente/métodos
3.
J Econ Entomol ; 106(1): 36-42, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23448012

RESUMEN

This study evaluates the effect of gamma radiation on the spore activity, toxicity, and crystal structures of two engineered Bacillus thuringiensis (Bt) strains, TnX and TnY, and the reference Bt strain HD-1. We attempted to identify dosages of cobalt-60 gamma radiation that would inactivate Bt spores but not affect its toxicity. In the radiation dosage range of 10-15 kilogray, no viable spore formation and no significant reduction of the efficiency of Bt against lepidopteran larvae were observed. However, further sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) results show that the components of the protoxin are affected by gamma radiation and that some bands are absent after treatment compared with the controls; the change in the protoxin band pattern depends on the type of Bt strain. Furthermore, the spore crystal structure of three Bt strains was studied with scanning electron microscopy and transmission electron microscopy. The results show that there are no changes in the size or shape of the treated Bt spores and crystals compared with the controls. The use of gamma radiation is effective to inactivate the spores of engineered Bt strains while preserving stable Bt toxicity against the target insect larvae.


Asunto(s)
Bacillus thuringiensis/efectos de la radiación , Proteínas Bacterianas/efectos de la radiación , Endotoxinas/efectos de la radiación , Proteínas Hemolisinas/efectos de la radiación , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/química , Proteínas Bacterianas/ultraestructura , Endotoxinas/química , Rayos gamma , Proteínas Hemolisinas/química , Proteínas Hemolisinas/ultraestructura , Microscopía Electrónica de Rastreo , Esporas Bacterianas/efectos de la radiación , Esporas Bacterianas/ultraestructura , Esterilización
4.
Sci Rep ; 13(1): 13149, 2023 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-37573389

RESUMEN

The accurate prediction of monthly runoff in the lower reaches of the Yellow River is crucial for the rational utilization of regional water resources, optimal allocation, and flood prevention. This study proposes a VMD-SSA-BiLSTM coupled model for monthly runoff volume prediction, which combines the advantages of Variational Modal Decomposition (VMD) for signal decomposition and preprocessing, Sparrow Search Algorithm (SSA) for BiLSTM model parameter optimization, and Bi-directional Long and Short-Term Memory Neural Network (BiLSTM) for exploiting the bi-directional linkage and advanced characteristics of the runoff process. The proposed model was applied to predict monthly runoff at GaoCun hydrological station in the lower Yellow River. The results demonstrate that the VMD-SSA-BiLSTM model outperforms both the BiLSTM model and the VMD-BiLSTM model in terms of prediction accuracy during both the training and validation periods. The Root-mean-square deviation of VMD-SSA-BiLSTM model is 30.6601, which is 242.5124 and 39.9835 lower compared to the BiLSTM model and the VMD-BiLSTM model respectively; the mean absolute percentage error is 5.6832%, which is 35.5937% and 6.3856% lower compared to the other two models, respectively; the mean absolute error was 19.8992, which decreased by 136.7288 and 25.7274 respectively; the square of the correlation coefficient (R2) is 0.93775, which increases by 0.53059 and 0.14739 respectively; the Nash-Sutcliffe efficiency coefficient was 0.9886, which increased by 0.4994 and 0.1122 respectively. In conclusion, the proposed VMD-SSA-BiLSTM model, utilizing the sparrow search algorithm and bidirectional long and short-term memory neural network, enhances the smoothness of the monthly runoff series and improves the accuracy of point predictions. This model holds promise for the effective prediction of monthly runoff in the lower Yellow River.

5.
Sci Rep ; 13(1): 15169, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37704827

RESUMEN

Against the backdrop of accelerated global climate change and urbanization, the frequency and severity of flood disasters have been increasing. In recent years, influenced by climate change, the Hai-River Basin (HRB) has experienced multiple large-scale flood disasters. During the widespread extraordinary flood event from July 28th to August 1st, 2023, eight rivers witnessed their largest floods on record. These events caused significant damage and impact on economic and social development. The development of hydrological models with better performance can help researchers understand the impacts of climate change, provide risk information on different disaster events within watersheds, support decision-makers in formulating adaptive measures, urban planning, and improve flood defense mechanisms to address the ever-changing climate environment. This study examines the potential for enhancing streamflow simulation accuracy in the HRB located in Northeast China by combining the physically-based hydrological model with the data-driven model. Three hybrid models, SWAT-D-BiLSTM, SWAT-C-BiLSTM and SWAT-C-BiLSTM with SinoLC-1, were constructed in this study, in which SWAT was used as a transfer function to simulate the base flow and quick flow generation process based on weather data and spatial features, and BiLSTM was used to directly predict the streamflow according to the base flow and quick flow. In the SWAT-C-BiLSTM model, SWAT parameters with P values less than 0.4 in each hydrological station-controlled watershed were calibrated, while the SWAT-D-BiLSTM model did not undergo calibration. Additionally, this study utilizes both 30 m resolution land use and land cover (LULC) map and the first 1 m resolution LULC map SinoLC-1 as input data for the models to explore the impact on streamflow simulation performance. Among five models, the NSE of SWAT-C-BiLSTM with SinoLC-1 reached 0.93 and the R2 reached 0.95 during the calibration period, and both of them stayed at 0.92 even in the validation period, while the NSE and R2 of the other four models were all below 0.90 in the validation period. The potential impact of climate change on streamflow in the HRB was evaluated by using predicted data from five global climate models from CMIP6 as input for the best-performing SWAT-C-BiLSTM with SinoLC-1. The results indicate that climate change exacerbates the uneven distribution of streamflow in the HRB, particularly during the concentrated heavy rainfall months of July and August. It is projected that the monthly streamflow in these two months will increase by 34% and 49% respectively in the middle of this century. Furthermore, it is expected that the annual streamflow will increase by 5.6% to 9.1% during the mid-century and by 6.7% to 9.3% by the end of the century. Both average streamflow and peak streamflow are likely to significantly increase, raising concerns about more frequent urban flooding in the capital economic region within the HRB.

6.
Sci Rep ; 13(1): 19341, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37935789

RESUMEN

To improve the accuracy of runoff forecasting, a combined forecasting model is established by using the kernel extreme learning machine (KELM) algorithm optimised by the butterfly optimisation algorithm (BOA), combined with the variational modal decomposition method (VMD) and the complementary ensemble empirical modal decomposition method (CEEMD), for the measured daily runoff sequences at Jiehetan and Huayuankou stations and Gaochun and Lijin stations. The results show that the combined model VMD-CEEMD-BOA-KELM predicts the best. The average absolute errors are 30.02, 23.72, 25.75, 29.37, and the root mean square errors are 20.53 m3/s, 18.79 m3/s, 18.66 m3/s, and 21.87 m3/s, the decision coefficients are all above 90 percent, respectively, and the Nash efficiency coefficients are all more than 90%, from the above it can be seen that the method has better results in runoff time series prediction.

7.
Sci Rep ; 13(1): 18915, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37919397

RESUMEN

Enhancing flood forecasting accuracy, promoting rational water resource utilization and management, and mitigating river disasters all hinge on the crucial role of improving the accuracy of daily flow prediction. The coupled model of Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN), Sample Entropy (SE), and Bidirectional Long Short-Term Memory (BiLSTM) demonstrates higher stability when faced with nonlinear and non-stationary data, stronger adaptability to various types and lengths of time series data by utilizing sample entropy, and significant advantages in processing sequential data through the BiLSTM network. In this study, in the context of predicting daily flow at the Huayuankou Hydrological Station in the lower reaches of the Yellow River, a coupled CEEMDAN-SE-BiLSTM model was developed and utilized. The results showed that the CEEMDAN-SE-BiLSTM coupled model achieved the utmost accuracy in prediction and optimal fitting performance. Compared with the CEEMDAN-SE-LSTM, CEEMDAN-BiLSTM, and BiLSTM coupled models, the root mean square error (RMSE) of this model is reduced by 42.77, 182.02, and 193.71, respectively; the mean absolute error (MAE) is reduced by 37.62, 118.60, and 126.67, respectively; and the coefficient of determination (R2) is increased by 0.0208, 0.1265, 0.1381.

8.
Sci Rep ; 13(1): 17168, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821598

RESUMEN

In order to enhance the simulation of BMPs (Best Management Practices) reduction effects in unmonitored watersheds, in this study, we combined the physically-based hydrological model Soil & Water Assessment Tool (SWAT) and the data-driven model Bi-directional Long Short-Term Memory (Bi-LSTM), using the very-high-resolution (VHR) Land Use and Land Cover (LULC) dataset SinoLC-1 as data input, to evaluate the feasibility of constructing a water environment model for the Ba-River Basin (BRB) in central China and improving streamflow prediction performance. In the SWAT-BiLSTM model, we calibrated the top five SWAT parameters sorted by P-Value, allowing SWAT to act as a transfer function to convert meteorological data into base flow and storm flow, serving as the data input for the Bi-LSTM model. This optimization improved the Bi-LSTM's learning process for the relationship between the target and explanatory variables. The daily streamflow prediction results showed that the hybrid model had 9 regions rated as "Very good," 2 as "Good," 2 as "Satisfactory," and 1 as "Unsatisfactory" among the 14 regions. The model achieved an NSE of 0.86, R2 of 0.85, and PBIAS of -2.71% for the overall daily streamflow prediction performance during the verification period of the BRB. This indicates that the hybrid model has high predictive accuracy and no significant systematic bias, providing a sound hydrodynamic environment for water quality simulation. The simulation results of different BMPs scenarios showed that in the scenarios with only one BMP measure, stubble mulch had the best reduction effect, with average reductions of 17.83% for TN and 36.17% for TP. In the scenarios with a combination of multiple BMP measures, the combination of stubble mulch, soil testing and formula fertilization, and vegetative filter strip performed the best, achieving average reductions of 42.71% for TN and 50.40% for TP. The hybrid model provides a novel approach to simulate BMPs' reduction effects in regions without measured hydrological data and has the potential for wide application in BMP-related decision-making.

9.
J Hosp Med ; 18(12): 1082-1091, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37933708

RESUMEN

BACKGROUND: Young adults with chronic childhood-onset diseases (CCOD) transitioning care from pediatrics to adult care are at high risk for readmission after hospital discharge. At our institution, we have implemented an inpatient service, the Med-Peds (MP) line, to improve transitions to adult care and reduce hospital utilization by young adults with CCOD. OBJECTIVE: This study aimed to assess the effect of the MP line on length of stay (LOS) and 30-day readmission rates compared to other inpatient services. METHODS: This was an observational, retrospective cohort analysis of patients admitted to the MP line compared to other hospital service lines over a 2-year period. To avoid potential confounding by indication for admission to the MP line, propensity score weighting methods were used. RESULTS: The MP line cared for 302 patients with CCOD from June 2019 to July 2021. Compared to other service lines, there was a 33% reduction in relative risk of 30-day readmission (26.9% compared to 40.3%, risk ratio = 0.67, 95% confidence interval [CI] 0.55-0.81). LOS was 10% longer for the MP line (event time ratio (ETR): 1.10 95% CI 1.0-1.21) with median LOS 4.8 versus 4.5 days. Patients with sickle cell disease had less of a reduction in 30-day readmissions and longer LOS. CONCLUSION: Hospitalization for young adults with CCOD on a MP service line was associated with lower 30-day readmission rates and longer LOS than hospitalization on other services. Further research is needed to assess which components of the line most contribute to decreased utilization.


Asunto(s)
Hospitalización , Readmisión del Paciente , Adulto Joven , Humanos , Niño , Estudios Retrospectivos , Tiempo de Internación , Alta del Paciente , Enfermedad Crónica , Hospitales
10.
J Econ Entomol ; 105(4): 1164-70, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22928294

RESUMEN

We studied the effect of combining microbial pesticides with camptothecin (CPT) on the mortality of two lepidopteran insects: Trichoplusia ni (Hübner) and Spodoptera exigua (Hübner). CPT is an alkaloid that is often used as an anticancer agent. Here, CPT was evaluated as a microbial pesticide synergist of Bacillus thuringiensis (Bt) and insect baculovirus. The toxicity of CPT and its synergistic effects on two microbial pesticides were studied using the diet overlay method. Bioassay results showed that CPT significantly enhances the toxicity of Bt variety kurstaki to S. exigua and T ni. In addition, CPT strongly enhanced the infectivity of Autographa californica (Speyer) multinucleocapsid nucleopolyhedrovirus (AcMNPV) and S. exigua nucleopolyhedrovirus (SeMNPV). Using light microscopy, we found that CPT disrupts the peritrophic membrane of T. ni larvae and severely affects the structure of the midgut, resulting in an abnormal gut lumen morphology. We speculate that CPT increases toxicity by affecting the permeability of the peritrophic membrane.


Asunto(s)
Bacillus thuringiensis , Camptotecina , Nucleopoliedrovirus , Sinergistas de Plaguicidas , Spodoptera , Animales , Agentes de Control Biológico , Camptotecina/farmacología , Tracto Gastrointestinal/efectos de los fármacos , Interacciones Huésped-Patógeno/efectos de los fármacos , Control de Insectos , Larva , Sinergistas de Plaguicidas/farmacología , Spodoptera/efectos de los fármacos
11.
J Econ Entomol ; 105(5): 1503-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23156143

RESUMEN

Baculoviruses and parasitoids are important biological control factors of insects in integrated pest management. Microplitis bicoloratus Chen (Hymenoptera: Braconidae: Microgastrina) is a solitary endoparasitoid of beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) larvae. M. bicoloratus parasitized first to third instars of S. exigua and most effectively parasitized second instars. The survival rate of parasitoids emerging from S. exigua multiple nucleopolyhedrovirus (SeMNPV)-infected hosts decreased with increasing SeMNPV doses at second to fourth instars. In addition, the mortality rate of the host was > 80% when coinfected with SeMNPV and M. bicoloratus, regardless of virus doses or the timing of virus treatment. Occlusion body production was significantly reduced in parasitized hosts. A comparison of host weights showed that hosts coinfected with SeMNPV and M bicoloratus were significantly lighter than those infected with SeMNPV alone, suggesting that the decrease in virus yield resulted from a reduction in larval growth. The viral genome copy number in parasitized host was significantly lower than that in nonparasitized host at 48 and 72 h postinfection. These results suggest that SeMNPV and M. bicoloratus are compatible as S. exigua control agents.


Asunto(s)
Nucleopoliedrovirus/crecimiento & desarrollo , Control Biológico de Vectores , Spodoptera/parasitología , Spodoptera/virología , Avispas/crecimiento & desarrollo , Avispas/virología , Animales , Femenino , Larva/crecimiento & desarrollo , Larva/parasitología , Larva/virología , Oviposición , Reacción en Cadena de la Polimerasa , Spodoptera/crecimiento & desarrollo
12.
Yao Xue Xue Bao ; 46(11): 1361-5, 2011 Nov.
Artículo en Zh | MEDLINE | ID: mdl-22260030

RESUMEN

The metabolic profile of pseudolaric acid B (PB) was investigated by using in vivo and in vitro tests. Pseudolaric acid C2 (PC2) was identified as the specific metabolite of PB in plasma, urine, bile and feces using HPLC and HPLC-ESI/MS(n) after both oral and intravenous administration to rats, and almost no prototype was detected in all kinds of samples. The metabolic behaviors of PB orally administered in rats treated with antibiotics to eliminate intestinal microflora were identical with those in untreated rats, demonstrating that the metabolism of PB is independent of intestinal microflora. PB was stable in 48 h respective incubation with artificial gastric juice and artificial intestinal juice, suggesting that neither pepsin nor trypsin is in charge of metabolism of PB, and also demonstrating that PB is stable in both pH environments of gastric tract and intestinal tract. In vitro research on metabolism of PB in rat liver microsomes incubation revealed that little PB was metabolized and that the proposed metabolites were the demethoxy and demethoxydecarboxy products of the prototype. The amount of metabolites was extremely low compared with the prototype, indicating that liver microsomes are not responsible for the metabolism of PB either. PB was gradually metabolized into PC2 during 1 h in whole blood incubation in vitro, and the metabolic process showed dynamically dependent manner with incubation time. Once absorbed into blood, PB was quickly metabolized into PC2, accordingly, little prototype was detected in all kinds of samples. The metabolism was attributed to the rapid hydrolysis of C-19 ester bond by plasma esterase. These results clarified the metabolic pathway of PB for the first time, which was of great significance to identify the in vivo active form and interpret acting mechanism of the active compounds of P. kaempferi.


Asunto(s)
Diterpenos/metabolismo , Redes y Vías Metabólicas , Pinaceae/química , Administración Intravenosa , Administración Oral , Animales , Bilis/metabolismo , Diterpenos/sangre , Diterpenos/orina , Esterasas/metabolismo , Heces/química , Hidrólisis , Masculino , Microsomas Hepáticos/metabolismo , Corteza de la Planta/química , Plantas Medicinales/química , Ratas , Ratas Sprague-Dawley
13.
Appl Radiat Isot ; 149: 52-59, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31029934

RESUMEN

A fast neutron imaging system, consisting of a deuterium-tritium neutron generator, an associated alpha-particle detector and an arc-shaped array of individual neutron detectors is simulated for fan-beam fast neutron tomography purpose. In this system, the associated particle and time of flight techniques are used to separate transmission neutrons from scattered neutrons by electronically collimating and time tagging the source neutrons. To evaluate factors affecting the system's spatial resolution and image quality, a series of simulations were performed with a GEANT4 based Monte Carlo program. The parameters include neutron detector resolution, system coincidence resolving time and reconstruction algorithm. The simulation results indicate that a reconstructed image resolution of about 2.1 mm can be obtained with an array of two hundred 4 mm resolution neutron detectors. With the aid of electronic collimation and time tagged based event filtering, the reconstructed image quality was significantly improved. Among iterative reconstruction algorithms tested, the Simultaneous Algebraic Reconstruction Technique-Total Variation algorithm showed better overall performance than others.

14.
World Neurosurg ; 126: e1140-e1146, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30880192

RESUMEN

BACKGROUND: Clear cell sarcoma (CCS) is a rare malignant soft tissue tumor with poor prognosis owing to metastasis and insensitive response to chemotherapy and radiotherapy. METHODS: We first searched PubMed and Embase using the terms "clear cell sarcoma," "malignant melanoma of soft tissue," "head," and "neck." In the 15 articles selected for literature review, only 27% (4/15) of patients were diagnosed with primary CCS of the head. Pathologically, those tumors arose from either the scalp or the superficial temporal fascia, but none invaded the skull and brain. Next, the search was performed in the same database using the terms "clear cell sarcoma," "malignant melanoma of soft tissue," and "bone," and only 24 articles were selected. RESULTS: In the case reported here, a 36-year-old woman was found to have a palpable mass located at the left temporal-occipital region, and surgical finding confirmed the invasion into the skull and the brain. The diagnosis of primary CCS was made because of the detection of t(12;22)(q13;q12) in >50% of tumor cells by fluorescence in situ hybridization, and metastasis to the lymph nodes and lungs was discovered by postoperative positron emission tomography-computed tomography. CONCLUSIONS: To the best of our knowledge, this is the first case of primary central nervous system CCS. Primary CCS may involve the skull and should be one of the differential diagnoses for intra-extracranial communicating tumors. Further research on biological characteristics and molecular targeted therapy of CCS are needed to improve its poor prognosis.


Asunto(s)
Neoplasias Encefálicas/patología , Sarcoma de Células Claras/patología , Neoplasias Craneales/patología , Adulto , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Femenino , Humanos , Neoplasias Pulmonares/secundario , Metástasis Linfática/patología , Sarcoma de Células Claras/diagnóstico , Sarcoma de Células Claras/genética , Neoplasias Craneales/diagnóstico , Neoplasias Craneales/genética , Translocación Genética
15.
Artículo en Inglés | MEDLINE | ID: mdl-18603488

RESUMEN

A liquid chromatography-diode array detection-electrospray ionization ion trap mass spectrometry (LC-DAD-ESI-MS(n)) method was established for the analysis of danshensu, caffeic acid, ferulic acid and isoferulic acid in rat plasma, bile, urine and feces after oral administration or intravenous injection. Liquid-liquid extraction was employed for the preparation of biosamples, and the chromatographic separation was carried out using an Agilent Zorbax Extend C(18) reversed phase column and acetonitrile-0.1% formic acid as the mobile phase. Totally nineteen metabolites were detected and identified as prototype, methylated, hydroxylated, sulfated and glucuronized conjugates. The metabolism of the individual phenolic acids in biosamples was investigated, and the metabolic pathway was proposed. By comparing the metabolism of different compounds which shared similar structures, we were able to find that methylation was the main pathway of danshensu metabolism, and the double bond on the side chain was critical for the drug excretion via bile and the formation of glucuronized conjugates. The results proved that the established method was simple, sensitive and reliable, which could be used to detect and identify the structures of metabolites and to better understand their in vivo metabolism.


Asunto(s)
Ácidos Cafeicos/análisis , Cromatografía Liquida/métodos , Cinamatos/análisis , Ácidos Cumáricos/análisis , Lactatos/análisis , Fenoles/metabolismo , Espectrometría de Masas en Tándem/métodos , Animales , Ácidos Cafeicos/metabolismo , Cinamatos/metabolismo , Ácidos Cumáricos/metabolismo , Heces/química , Lactatos/metabolismo , Redes y Vías Metabólicas , Fenoles/sangre , Fenoles/orina , Ratas , Reproducibilidad de los Resultados , Espectrometría de Masa por Ionización de Electrospray/métodos
16.
J Chromatogr Sci ; 46(2): 184-90, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18366881

RESUMEN

A systematic study on pharmacokinetics and tissue distribution of danshensu (one of the major active components from Salvia miltiorrhizae) is conducted using a rapid and sensitive high-performance liquid chromatographic (HPLC) method. Before HPLC analysis, biological samples are pretreated with a liquid-liquid extraction. Separation of danshensu and internal standard is achieved on an Agilent Zorbax C18 column with a mobile phase made up of acetonitrile and 0.05% trifluoracetic acid at a flow rate of 0.8 mL/min. The calibration curves in plasma and tissues are linear in the given concentration ranges, with r2 no less than 0.99. The intra-day and inter-day relative standard deviations in the measurement of quality control samples are less than 15%, and the accuracies are in the range of 86-115%. The recoveries of danshensu in plasma and tissues are among 80% to 118%. Meanwhile, the multi-peaks in pharmacokinetic profiles are observed. The method is successfully applied to the pharmacokinetics and tissue distribution study of danshensu after a single oral administration of 50.0 mg/kg sodium danshensu to rats.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Lactatos/farmacocinética , Animales , Encéfalo/metabolismo , Riñón/metabolismo , Lactatos/administración & dosificación , Lactatos/análisis , Lactatos/sangre , Hígado/metabolismo , Pulmón/metabolismo , Masculino , Miocardio/metabolismo , Ratas , Ratas Sprague-Dawley , Bazo/metabolismo , Distribución Tisular
17.
J Chromatogr B Analyt Technol Biomed Life Sci ; 856(1-2): 100-7, 2007 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-17599847

RESUMEN

A method using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-MS/MS) analysis was established for the identification of metabolites in rat after oral administration of protocatechuic aldehyde, a major bioactive phenolic acid in the roots of Salvia miltiorrhiza. Eleven metabolites in rat plasma and urine were firstly identified as protocatechuic aldehyde, protocatechuic acid and their methylated, glucuronized or glycine conjugates on the basis of their MS fragmentation behaviors, while nine of these metabolites (except protocatechuic aldehyde and protocatechuic acid) were detected in rat bile. In addition, the possible metabolic pathway was proposed for the first time. In the phase I metabolism, protocatechuic aldehyde could be oxidized to protocatechuic acid. The conjugates would be formed in rat intestine, liver and kidney and excreted from rat urine and bile. Enthrohepatic circulation played an important role in the metabolism of protocatechuic aldehyde. The results proved that the established method was simple, reliable and sensitive, revealing that it could be used to rapid screen and identify the structures of active components responsible for pharmacological effects of protocatechuic aldehyde and to better understand its in vivo metabolism.


Asunto(s)
Benzaldehídos/análisis , Catecoles/análisis , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Administración Oral , Animales , Benzaldehídos/administración & dosificación , Benzaldehídos/farmacocinética , Catecoles/administración & dosificación , Catecoles/farmacocinética , Masculino , Ratas , Ratas Sprague-Dawley
18.
J Chromatogr B Analyt Technol Biomed Life Sci ; 858(1-2): 184-98, 2007 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-17875406

RESUMEN

This study was conducted to compare the in vivo metabolites of salvianolic acid B (Sal B) between normal rats and antibiotic-treated rats and to clarify the role of intestinal bacteria on the absorption, metabolism and excretion of Sal B. A valid method using LC-MS(n) analysis was established for identification of rat biliary and fecal metabolites. And isolation of normal rat urinary metabolites by repeated column chromatography was applied in this study. Four biliary metabolites and five fecal metabolites in normal rats were identified on the basis of their MS(n) fragmentation patterns. Meanwhile, two normal rat urinary metabolites were firstly identified on the basis of their NMR and MS data. In contrast, no metabolites were detected in antibiotic-treated rat urine and bile, while the prototype of Sal B was found in antibiotic-treated rat feces. The differences of in vivo metabolites between normal rats and antibiotic-treated rats were proposed for the first time. Furthermore, it was indicated that the intestinal bacteria showed an important role on the absorption, metabolism and excretion of Sal B. This investigation provided scientific evidence to infer the active principles responsible for the pharmacological effects of Sal B.


Asunto(s)
Benzofuranos/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Salvia miltiorrhiza/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Animales , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Benzofuranos/química , Benzofuranos/farmacocinética , Masculino , Estructura Molecular , Neomicina/farmacología , Ratas , Ratas Sprague-Dawley , Estreptomicina/farmacología
19.
Virol Sin ; 30(6): 417-24, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26712716

RESUMEN

The complete genome of Cnaphalocrocis medinalis granulovirus (CnmeGV) from a serious migratory rice pest, Cnaphalocrocis medinalis (Lepidoptera: Pyralidae), was sequenced using the Roche 454 Genome Sequencer FLX system (GS FLX) with shotgun strategy and assembled by Roche GS De Novo assembler software. Its circular double-stranded genome is 111,246 bp in size with a high A+T content of 64.8% and codes for 118 putative open reading frames (ORFs). It contains 37 conserved baculovirus core ORFs, 13 unique ORFs, 26 ORFs that were found in all Lepidoptera baculoviruses and 42 common ORFs. The analysis of nucleotide sequence repeats revealed that the CnmeGV genome differs from the rest of sequenced GVs by a 23 kb and a 17kb gene block inversions, and does not contain any typical homologous region (hr) except for a region of non-hr-like sequence. Chitinase and cathepsin genes, which are reported to have major roles in the liquefaction of the hosts, were not found in the CnmeGV genome, which explains why CnmeGV infected insects do not show the phenotype of typical liquefaction. Phylogenetic analysis, based on the 37 core baculovirus genes, indicates that CnmeGV is closely related to Adoxophyes orana granulovirus. The genome analysis would contribute to the functional research of CnmeGV, and would benefit to the utilization of CnmeGV as pest control reagent for rice production.


Asunto(s)
Genoma Viral , Granulovirus/genética , Granulovirus/aislamiento & purificación , Lepidópteros/virología , Secuencia de Aminoácidos , Animales , Composición de Base , Secuencia de Bases , Replicación del ADN/genética , Genes Virales , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Oryza , Alineación de Secuencia , Análisis de Secuencia de ADN , Proteínas Virales/genética
20.
Appl Radiat Isot ; 82: 293-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24135636

RESUMEN

A depth discrimination method is devised based on a multirow linear array detector for push-broom Compton scatter imaging. Two or more rows of detector modules are placed at different positions towards a sample. An improved parallel-hole collimator is fixed in front of the modules to restrict their fields of view. The depth information could be indicated by comparing the signal differences. In addition, an available detector and several related simulations using GEANT4 are given to support the method well.

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