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1.
Xenobiotica ; : 1-42, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32174209

RESUMO

1. Coumarins have aroused high interests due to their diverse bioactivities. Understanding of its metabolism contributes to determine the druggability of coumarin in vivo.2. A sensitive and efficient strategy based on ultra-performance liquid chromatography-mass spectrometer (UPLC-MS) analysis combined with various data-processing techniques including metabolomics and multiple mass defect filter (MMDF) was established for the comprehensive screening and elucidation of potential coumarin metabolites.3. Total 20 metabolites of scoparone were identified in this study, including 14 undescribed metabolites. The metabolism of two other similar coumarins scopoletin and esculetin also could be determined using this strategy.4. By the established strategy, this study gives the insights about the major metabolic pathways of scoparone in vivo and in vitro metabolism, including demethylation, hydroxylation, hydration, cysteine conjugation, glucuronide conjugation and sulfate conjugation. Additionally, the metabolic pathways of scopoletin and esculetin were determined as hydroxylation, glucuronidation and sulfation. These results contribute to the understanding of metabolic characterization of coumarins, and demonstrate that the combination of UPLC-MS-based metabolomics and MMDF is a powerful approach to determine the metabolic pathways of coumarin compounds.

2.
J Pharm Biomed Anal ; 180: 113045, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31887668

RESUMO

Nintedanib is a promising tyrosine kinase inhibitor for clinically treating idiopathic pulmonary fibrosis (IPF). Some clinical cases reported that nintedanib treatment can cause hepatotoxicity and myocardial toxicity. U. S. FDA warns the potential drug-drug interaction when it is co-administrated with other drugs. In order to understand the potential toxicity of nintedanib and avoid drug-drug interaction, the metabolism of nintedanib was systematically investigated in human liver microsomes and mice using metabolomics approach, and the toxicity of metabolites was predicted by ADMET lab. Nineteen metabolites were detected in vivo and in vitro metabolism, and 8 of them were undescribed. Calculated partition coefficients (Clog P) were used to distinguish the isomers of nintedanib metabolites in this study. The major metabolic pathways of nintedanib majorly included hydroxylation, demethylation, glucuronidation, and acetylation reactions. The ADMET prediction indicated that nintedanib was a substrate of the cytochrome P450 3A4 (CYP3A4) and P-glycoprotein (P-gp). And nintedanib and most of its metabolites might possess potential hepatotoxicity and cardiotoxicity. This study provided a global view of nintedanib metabolism, which could be used to understand the mechanism of adverse effects related to nintedanib and its potential drug-drug interaction.

3.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3562-3568, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602923

RESUMO

The mass spectrometry-based metabolomics method was used to systematically investigate the formation of celastrol metabolites,and the effect of celastrol on endogenous metabolites. The mice plasma,urine and feces samples were collected after oral administration of celastrol. Ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry( UPLC-QTOF-MS) was applied to analyze the exogenous metabolites of celastrol and its altered endogenous metabolites. Mass defect filtering was adopted to screen for the exogenous metabolites of celastrol. Multivariate statistical analysis was used to identify the endogenous metabolites affected by celastrol. Celastrol and its eight metabolites were detected in urine and feces of mice,and 5 metabolites of them were reported for the first time. The hydroxylated metabolites were observed in the metabolism of both human liver microsomes and mouse liver microsomes. Further recombinant enzyme experiments revealed CYP3 A4 was the major metabolic enzyme involved in the formation of hydroxylated metabolites. Urinary metabolomics revealed that celastrol can affect the excretion of intestinal bacteria-related endogenous metabolites,including hippuric acid,phenylacetylglycine,5-hydroxyindoleacetic acid,urocanic acid,cinnamoylglycine,phenylproplonylglycine and xanthurenic acid. These results are helpful to elucidate the metabolism and disposition of celastrol in vivo,and its mechanism of action.


Assuntos
Metabolômica , Triterpenos/farmacocinética , Animais , Cromatografia Líquida de Alta Pressão , Humanos , Espectrometria de Massas , Camundongos , Microssomos Hepáticos/metabolismo , Triterpenos/metabolismo
4.
Chem Res Toxicol ; 32(10): 1965-1976, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31468958

RESUMO

Elemicin is a constituent of natural aromatic phenylpropanoids present in many herbs and spices. However, its potential to cause toxicity remains unclear. To examine the potential toxicity and associated mechanism, elemicin was administered to mice for 3 weeks and serum metabolites were examined. Enlarged livers were observed in elemicin-treated mice, which were accompanied by lower ratios of unsaturated- and saturated-lysophosphatidylcholines in plasma, and inhibition of stearoyl-CoA desaturase 1 (Scd1) mRNA expression in liver. Administration of the unsaturated fatty acid oleic acid reduced the toxicity of 1'-hydroxylelemicin, the primary oxidative metabolite of elemicin, while treatment with the SCD1 inhibitor A939572 potentiated its toxicity. Furthermore, the in vitro use of recombinant human CYPs and chemical inhibition of CYPs in human liver microsomes revealed that CYP1A1 and CYP1A2 were the primary CYPs responsible for elemicin bioactivation. Notably, the CYP1A2 inhibitor α-naphthoflavone could attenuate the susceptibility of mice to elemicin-induced hepatomegaly. This study revealed that metabolic activation of elemicin leads to SCD1 inhibition in liver, suggesting that upregulation of SCD1 may serve as potential intervention strategy for elemicin-induced toxicity.

5.
J Agric Food Chem ; 67(29): 8243-8252, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31271289

RESUMO

Elemicin, an alkenylbenzene constituent of natural oils of several plant species, is widely distributed in food, dietary supplements, and medicinal plants. 1'-Hydroxylation is known to cause metabolic activation of alkenylbenzenes leading to their potential toxicity. The aim of this study was to explore the relationship between elemicin metabolism and its toxicity through comparing the metabolic maps between elemicin and 1'-hydroxyelemicin. Elemicin was transformed into a reactive metabolite of 1'-hydroxyelemicin, which was subsequently conjugated with cysteine (Cys) and N-acetylcysteine (NAC). Administration of NAC could significantly ameliorate the elemicin- and 1'-hydroxyelemicin-induced cytotoxicity of HepG2 cells, while depletion of Cys with diethyl maleate (DEM) increased cytotoxicity. Recombinant human CYP screening and CYP inhibition experiments revealed that multiple CYPs, notably CYP1A1, CYP1A2, and CYP3A4, were responsible for the metabolic activation of elemicin. This study revealed that metabolic activation plays a critical role in elemicin cytotoxicity.


Assuntos
Pirogalol/análogos & derivados , Ativação Metabólica , Biotransformação , Sobrevivência Celular/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Células Hep G2 , Humanos , Hidroxilação , Estrutura Molecular , Pirogalol/química , Pirogalol/metabolismo , Pirogalol/toxicidade
6.
J Agric Food Chem ; 67(15): 4328-4336, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30912427

RESUMO

Myristicin is widely distributed in spices and medicinal plants. The aim of this study was to explore the role of metabolic activation of myristicin in its potential toxicity through a metabolomic approach. The myristicin- N-acetylcysteine adduct was identified by comparing the metabolic maps of myristicin and 1'-hydroxymyristicin. The supplement of N-acetylcysteine could protect against the cytotoxicity of myristicin and 1'-hydroxymyristicin in primary mouse hepatocytes. When the depletion of intracellular N-acetylcysteine was pretreated with diethyl maleate in hepatocytes, the cytotoxicity induced by myristicin and 1'-hydroxymyristicin was deteriorated. It suggested that the N-acetylcysteine adduct resulting from myristicin bioactivation was closely associated with myristicin toxicity. Screening of human recombinant cytochrome P450s (CYPs) and treatment with CYP inhibitors revealed that CYP1A1 was mainly involved in the formation of 1'-hydroxymyristicin. Collectively, this study provided a global view of myristicin metabolism and identified the N-acetylcysteine adduct resulting from myristicin bioactivation, which could be used for understanding the mechanism of myristicin toxicity.


Assuntos
Compostos de Benzil/metabolismo , Compostos de Benzil/toxicidade , Dioxolanos/metabolismo , Dioxolanos/toxicidade , Hepatócitos/efeitos dos fármacos , Pirogalol/análogos & derivados , Acetilcisteína/química , Acetilcisteína/metabolismo , Ativação Metabólica , Animais , Compostos de Benzil/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocromo P-450 CYP1A1/metabolismo , Dioxolanos/química , Hepatócitos/citologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pirogalol/química , Pirogalol/metabolismo , Pirogalol/toxicidade
7.
Xenobiotica ; 49(6): 655-670, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29897827

RESUMO

To elucidate the metabolism of pazopanib, a metabolomics approach was performed based on ultra-performance liquid chromatography coupled with electrospray ionization quadrupole mass spectrometry. A total of 22 pazopanib metabolites were identified in vitro and in vivo. Among these metabolites, 17 were novel, including several cysteine adducts and aldehyde derivatives. By screening using recombinant CYPs, CYP3A4 and CYP1A2 were found to be the main forms involved in the pazopanib hydroxylation. Formation of a cysteine conjugate (M3), an aldehyde derivative (M15) and two N-oxide metabolites (M18 and M20) from pazopanib could induce the oxidative stress that may be responsible in part for pazopanib-induced hepatotoxicity. Morphological observation of the liver suggested that pazopanib (300 mg/kg) could cause liver injury. The aspartate transaminase and alanine aminotransferase in serum significantly increased after pazopanib (150, 300 mg/kg) treatment; this liver injury could be partially reversed by the broad-spectrum CYP inhibitor 1-aminobenzotriazole (ABT). Metabolomics analysis revealed that pazopanib could significantly change the levels of L-carnitine, proline and lysophosphatidylcholine 18:1 in liver. Additionally, drug metabolism-related gene expression analysis revealed that hepatic Cyp2d22 and Abcb1a (P-gp) mRNAs were significantly lowered by pazopanib treatment. In conclusion, this study provides a global view of pazopanib metabolism and clues to its influence on hepatic function.


Assuntos
Antineoplásicos/toxicidade , Fígado/efeitos dos fármacos , Pirimidinas/toxicidade , Sulfonamidas/toxicidade , Alanina Transaminase/sangue , Animais , Antineoplásicos/metabolismo , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/fisiologia , Fígado/metabolismo , Fígado/patologia , Masculino , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Análise Multivariada , Estresse Oxidativo/efeitos dos fármacos , Pirimidinas/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Sulfonamidas/metabolismo
8.
J Pharm Biomed Anal ; 159: 524-535, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30055476

RESUMO

Regorafenib is a novel tyrosine kinase inhibitor, which has been approved by the United States Food and Drug Administration for the treatment of various tumors. The purpose of the present study was to describe the metabolic map of regorafenib, and investigate its effect on liver function. Mass spectrometry-based metabolomics approach integrated with multiple mass defect filter was used to determine the metabolites of regorafenib in vitro incubation mixtures (human liver microsomes and mouse liver microsomes), serum, urine and feces samples from mice treated with 80 mg/kg regorafenib. Eleven metabolites including four novel metabolites were identified in the present investigation. As halogen substituted drug, reductive defluorination and oxidative dechlorination metabolites of regorafenib were firstly report in present study. By screening using recombinant cytochrome P450 s (CYPs), CYP3A4 was found to be the principal isoforms involved in regorafenib metabolism. The predication with a molecular docking model confirmed that regorafenib had potential to interact with the active sites of CYP3A4, CYP3A5 and CYP2D6. Serum chemistry analysis revealed no evidence of hepatic damage from regorafenib exposure. This study provided a global view of regorafenib metabolism and its potential side-effects.


Assuntos
Metabolômica , Compostos de Fenilureia/farmacocinética , Piridinas/farmacocinética , Animais , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Antineoplásicos/urina , Citocromo P-450 CYP3A/metabolismo , Fezes/química , Humanos , Fígado/efeitos dos fármacos , Espectrometria de Massas , Camundongos , Microssomos Hepáticos/metabolismo , Simulação de Acoplamento Molecular , Compostos de Fenilureia/sangue , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/urina , Piridinas/sangue , Piridinas/farmacologia , Piridinas/urina
10.
Fitoterapia ; 119: 45-50, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28390973

RESUMO

Three new neolignans, lycocernuasides B-D (1-3), three new serratane triterpenoids, lycernuic ketones D (8) and E (9), and lycernuic A (10), together with six known compounds, were isolated from the 75% aqueous EtOH extract of Palhinhaea cernua. Their structures and absolute configurations were established primarily by NMR, HRESIMS and circular dichroism (CD). All compounds were evaluated the inhibitory activities of xanthine oxidase. Compounds 1-3 displayed moderate inhibitory effects on xanthine oxidase with IC50 values of 30.36µM, 42.65µM and 35.33µM, respectively.


Assuntos
Lignanas/química , Lycopodiaceae/química , Triterpenos/química , Xantina Oxidase/antagonistas & inibidores , Animais , Bovinos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Lignanas/isolamento & purificação , Estrutura Molecular , Triterpenos/isolamento & purificação
11.
J Asian Nat Prod Res ; 19(11): 1087-1092, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28303722

RESUMO

A new cyclic diarylheptanoid (1) and a new flavone glucoside (2), along with seven known compounds, were isolated from the green peel of Juglans mandshurica. Their structures were elucidated based on extensive spectroscopic analyses. Moreover, the cytotoxicity against NCI-H460, A549, and K562 cancer cells of compounds 1-6 was evaluated. The results showed that compound 3 exhibited moderate inhibitory potency against the growth of three cell lines.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Diarileptanoides/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Flavonas/isolamento & purificação , Glucosídeos/isolamento & purificação , Juglans/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Diarileptanoides/química , Diarileptanoides/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Flavonas/química , Flavonas/farmacologia , Glucosídeos/química , Glucosídeos/farmacologia , Células Hep G2 , Humanos , Células K562 , Estrutura Molecular , Extratos Vegetais/química
12.
Ying Yong Sheng Tai Xue Bao ; 28(5): 1431-1440, 2017 May 18.
Artigo em Chinês | MEDLINE | ID: mdl-29745177

RESUMO

Soil infiltration, soil physical and chemical properties, root length density and soil fauna diversity were studied in Phyllostachys heterocycla forests with different mulching times in southwest Zhejiang Province, China. Significant differences of soil infiltration capability were found among the forests with different mulching times and among soil layers. Soil infiltration capability generally declined in the deeper soil layers. With mulching management, soil infiltration capability increased under the first mulching, and then declined with the increase of mulching times. The Kostiakov model was suitable for simulating soil infiltration process. With the extending of mulching times (4 to 6 years), soil pH and total/non-capillary porosity decreased, while soil bulk density, soil orga-nic matter and total nitrogen contents increased significantly. Soil initial, steady, and average infiltration rates as well as the cumulative infiltration amount correlated closely with the length density of roots with diameter from 0.5 mm to 5.0 mm, showing a decreasing tendency with the decrease in root length density. Soil fauna density was highest in the forest under the first mulching, and was lowest after third mulching. The decreased numbers of large and meso-arthropods, including Symphyla, Chilopoda, Diplopoda, Hymenoptera and pseudoscorpions, and the micro-arthropods, including Oribatida, Mesostigmata, Onychiuridae, Neanuridae, Cyphoderidae, and Entomobryidae, showed negative effects on soil infiltration. In conclusion, long-term mulching changed soil physical and chemical properties, decreased soil infiltration capability, and suppressed the development of soil fauna, which might cause the decline ofP. heterocycla forests.


Assuntos
Florestas , Poaceae , Animais , China , Nitrogênio , Solo
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(12): 3836-41, 2016 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-30234952

RESUMO

Tissue intrinsic fluorescence spectrum refers to the fluorescence that is not impaired by tissue absorption and scattering which has the ability to reflect tissue biochemical properties. In order to reduce the influence of tissue absorption and scattering properties on tissue fluorescence spectrum, and then recover tissue intrinsic fluorescence spectrum, a tissue spectrum detection system based on fiber-optic probe was developed for the measurement of tissue fluorescence spectrum and diffusion reflectance spectrum at the same place. On the other hand, diffusion theory was introduced to extract the tissue physiological parameters from the measurement tissue diffusion reflectance spectrum, which included blood volume fraction, oxyhemoglobin saturation, melanin content, reduce scattering coefficient at 500 nm and the ratio of rayleigh scattering and the total scattering. Then tissue optical parameters in visible wavelengths were calculated. According to the tissue optical parameters and measured tissue diffusion spectrum, the intrinsic fluorescence spectrum was recovered from the measured fluorescence. Based on this, clinical trials were conducted to measure human skin fluorescence spectrum and diffusion reflectance spectrum, and then to recover skin intrinsic fluorescence spectrum. Finally, the accumulation of Advanced Glycation End products (AGE) in human skin was evaluated and the probability of diabetes mellitus was predicted. The result shows that the sensitivity and specificity were 69% and 0.75% respectively, when the measured fluorescent was used to screening diabetes mellitus. At the same specificity, the sensitivity was 90% when the recovered intrinsic fluorescence was employed to screening diabetes mellitus.


Assuntos
Espectrometria de Fluorescência , Difusão , Tecnologia de Fibra Óptica , Humanos , Espalhamento de Radiação
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(10): 3215-21, 2016 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-30246515

RESUMO

Due to the urgent need for noninvasive detection of skin cholesterol, a portable, intelligent and real-time skin diffuse reflectance spectroscopy measurement system was designed based on a micro-spectrometer. Digitonin-horseradish peroxidase copolymer solution was prepared. According to the properties digitonin binds to the hydroxy of cholesterol molecular specifically and the horseradish peroxidase reacts with TMB color solution (the main component is 3,3',5,5'-tetramethylbenzidine ) a color change was produced, by which the skin cholesterol was identified and instructed with high sensitivity and high specificity, and the concentration of skin cholesterol was quantified by measuring the degree of color change. In order to validate the feasibility of this method, pig skin which is similar to human skin was taken as the experimental subject, and cholesterol samples of gradient concentration were achieved through the extraction. After that the spectroscopy measurement system was adopted to detect the cholesterol concentration. The experiment result showed that, relative diffuse reflectance can distinguish the cholesterol samples with different concentrations, and the diffuse reflectance intensity factor can quantity the concentrations of cholesterol at characteristic wavelengths (442, 450 and 463 nm) and characteristic wavelength band of 442~500 nm. Linear fitting curves were obtained with the determination coefficient R2 were 0.960, 0.959, 0.958 and 0.958, respectively. The study has shown that, using diffuse reflectance spectroscopy technology can realize noninvasive rapid detection of skin cholesterol, and applying it to the risk assessment of atherosclerotic diseases would contribute to the prevention and control of such diseases significantly.


Assuntos
Pele , Análise Espectral , Animais , Colesterol , Humanos , Suínos
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(5): 1327-31, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25095432

RESUMO

Advanced glycation end products (AGEs) are highly associated with hyperglycemia in human skin tissue, and they also have the autofluorescence characteristic. A self-developed optical noninvasive detection device was used to measure the autofluorescence in human skin tissue, and then a neural network pattern recognition model was used to assess the risk of diabetes mellitus of the subject under survey. After the fluorescence spectra were acquired and processed with principal component analysis, four of the leading principal components were chosen to represent a whole spectrum. The established neural network pattern recognition model has 4 input nodes, 6 hidden nodes and 1 output node. A dataset consisting of 487 cases collected in Anhui Provincial Hospital was used to train the model. Seventy percent cases were used as the training set, 15% as the validation set and 15% as the test set. The model can output subject's risk of diabetes mellitus, or a dichotomous judgment. Receiver operating characteristic curve can be drawn with the area under curve of 0. 81, with standard error of 0. 02. When using 0. 5 as the threshold between diabetes mellitus and non-diabetes mellitus, the sensitivity and specificity of this model is 72. 4% and 77. 6% respectively, and the overall accuracy is 74. 9%. The method using human skin autofluorescence spectrum combined with neural network pattern recognition model is proposed for the first time, and the results show that this method has a better screening effect compared with currently used fasting plasma glucose and HbAlc.


Assuntos
Diabetes Mellitus/diagnóstico , Fluorescência , Produtos Finais de Glicação Avançada/análise , Humanos , Hiperglicemia/diagnóstico , Reconhecimento Automatizado de Padrão , Medição de Risco , Sensibilidade e Especificidade , Pele , Espectrometria de Fluorescência
16.
Ying Yong Sheng Tai Xue Bao ; 25(3): 797-802, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24984499

RESUMO

A pot experiment was conducted to study the effects of adding different amounts of wheat straw (0 g x kg(-1), N0; 2.08 g x kg(-1), N1) and phosphorus (0 mg x kg(-1), P0; 100 mg x kg(-1), P1; 200 mg x kg(-1), P2; 400 mg x kg(-1), P3) on microorganism community in a soil of low-phosphorus. Adding straw and phosphorus had significant effects on the soil microbial total biomass (MTB), bacterial biomass (MB), fungal biomass (FB), and fungi to bacteria ratio (F/B), which all decreased in order of N1P1>N1P0>N1P2>N1P3>N0P1>N0P2>N0P3. MTB, MB, FB and F/B ratio of the wheat straw addition treatments were all significantly higher than in the non-straw addition treatments under the same level of phosphorus addition. As for the same wheat straw addition, MTB, MB, FB and F/B ratio increased firstly and then decreased with increasing the level of phosphorus addition, and the combinations of P1 level were optimal.


Assuntos
Fósforo/análise , Caules de Planta/química , Microbiologia do Solo , Solo/química , Triticum , Biomassa
17.
Ying Yong Sheng Tai Xue Bao ; 24(3): 607-13, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23755470

RESUMO

Based on the field survey and laboratory analysis, this paper studied the soil aggregate stability and soil organic carbon characteristics in Quercus variabilis and Pinus tabulaeformis plantations in Beijing area. In the two plantations, the contents of soil macro-aggregates decreased with soil depth. In P. tabulaeformis plantation, soil macro-aggregates (>0.25 mm) occupied the majority, accounting for 71% -77% of the total; whereas in Q. variabilis plantation, no significant difference was observed in the contents of soil macro-aggregates and micro-aggregates (< or =0.25 mm), which accounted for 51% -58% and 42% -49%, respectively. Both the mean mass diameter and the geometrical mean mass diameter of the soil aggregates in P. tabulaeformis plantation were significantly higher than those in Q. variabilis plantation, and the fractal dimension (D) of the soil water-stable aggregates in P. tabulaeformis plantation was lower than that in Q. variabilis plantation, suggesting that P. tabulaeformis plantation was more favorable for the soil aggregate stability than Q. variabilis plantation. Also in the two plantations, the organic carbon content in soil water-stable aggregates decreased with soil depth. The organic carbon content in soil macro-aggregates was significantly higher in P. tabulaeformis plantation (58% -83%) than in Q. variabilis plantation (49% -66% ). It was suggested that in Beijing area, P. tabulaeformis plantation was more beneficial to the soil organic carbon protection, as compared with Q. variabilis plantation.


Assuntos
Carbono/análise , Compostos Orgânicos/análise , Pinus/crescimento & desenvolvimento , Quercus/crescimento & desenvolvimento , Solo/química , China , Ecossistema , Água/análise
18.
Zhonghua Zhong Liu Za Zhi ; 35(11): 828-32, 2013 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-24447480

RESUMO

OBJECTIVE: To detect the expression of prostate cancer antigen-1 (PCA-1) in prostate cancer, and to analyze the effects of downregulation of PCA-1 expression on malignant biological behavior of prostate cancer LNCaP cells, and to explore their possible molecular mechanisms. METHODS: PCA-1-siRNA and control siRNA were transfected into LNCaP cells with lipofectamine 2000. The cell cycle, proliferation and migration were determined by methyl thiazolyl tetrazolium (MTT) assay, flow cytometry and Transwell chambers, respectively. Western blotting was used to detect the expression of cyclin E, matrix metallopeptidase 9 (MMP-9) and p21. Immunohistochemistry was used to detect the expression of PCA-1 protein in 126 cases of prostate cancer and 88 cases of benign prostatic hyperplasia (BPH). RESULTS: The positive rate of PCA-1 expression was 77.8% (98/126) in prostate cancer, and 10.2% (9/88) in BPH, and its expression was not significantly related to age, prostate specific antigen (PSA), Eastern Cooperative Oncology Group (ECOG) score (P > 0.05), and was associated with Gleason score, TNM staging and bone metastasis (P < 0.05). Downregulation of PCA-1 expression inhibited cell proliferation, arrested cell cycle at S phase and decreased cell migration of LNCaP cells. The downregulation of PCA-1 expression decreased the expression of Bcl-xl, cyclin E and MMP-9 proteins, but increased the expression of p21 proteins. CONCLUSIONS: PCA-1 may play an important role in the development of prostate cancer. The downregulation of PCA-1 expression can lead to changes in the proliferation, cell cycle and migration of prostate cancer LNCaP cells, and these effects may be associated with the decrease of Bcl-xl, cyclin E and MMP-9 proteins and increase of p21 protein.


Assuntos
Antígenos de Neoplasias/metabolismo , Ciclo Celular , Movimento Celular , Proliferação de Células , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/genética , Linhagem Celular Tumoral , Ciclina E/metabolismo , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteínas Oncogênicas/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , RNA Interferente Pequeno/genética , Transfecção , Proteína bcl-X/metabolismo
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(1): 230-2, 2010 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-20302120

RESUMO

The necessity to measure advanced glycation endproducts (AGE) was analyzed in the present paper, and the apparatus for measuring skin autofluorescence was also designed making use of the special excitation spectrum and emission spectrum. A portion of tissue at the volar side of the arm of individuals (11 diabetes and 19 control subjects) was illuminated with excitation light, i.e., monochromatic light around 370 nm, and the emission spectrum was detected on the skin of control subjects and diabetic patients respectively. All measurements were performed at room temperature in a semi-dark environment. It can be seen that different sites of an individual could lead to different results, and the color can also affect the results. The technology of fluorescence precorrection was applied in order to get rid of the influence of noise, different site of skin, the color of skin etc. The result indicates that the technology of precorrection is of avail and the repetitiveness is well.


Assuntos
Produtos Finais de Glicação Avançada/química , Pele/química , Análise Espectral , Estudos de Casos e Controles , Diabetes Mellitus , Fluorescência , Humanos
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