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1.
Huan Jing Ke Xue ; 45(3): 1337-1348, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471850

RESUMO

Carbonaceous aerosol, as an important component of atmospheric aerosol, has a significant impact on atmospheric environmental quality, human health, and global climate change. To investigate the characteristics and sources of carbonaceous aerosol in atmospheric fine particulate matter (PM2.5) in Huaxi District of Guiyang, an in-situ observational study was conducted during different seasons in 2020, and the carbonaceous components of PM2.5 were measured using a thermal-optical carbon analyzer (DRI Model 2015). The results of the study showed that the average concentrations of PM2.5, total carbonaceous aerosol (TCA), organic carbon (OC), secondary organic carbon (SOC), and elemental carbon (EC) concentrations during the observation period were (39.7±22.3), (14.1±7.2), (7.6±3.9), (4.4±2.6), and (2.0±1.0) µg·m-3, respectively, and the mean value of OC/EC was (3.9±0.8). ρ(PM2.5), ρ(TCA), ρ(OC), ρ(SOC), and ρ(EC) showed a seasonal variation pattern with the highest in winter [(52.6±28.6), (17.0±9.6), (9.1±5.2), (6.1±3.9), and (2.4±1.2) µg·m-3, respectively] and the lowest in summer [(25.1±7.1), (11.6±3.6), (6.3±1.9), (3.7±1.2), and (1.6±0.6) µg·m-3, respectively]. The seasonal variation in OC/EC showed summer (4.2±0.8) > winter (3.8±0.9) > autumn (3.8±0.5) > spring (3.7±0.9), indicating the presence of SOC generation in all seasons in Huaxi District. SOC showed a significant correlation with OC (R2 =0.9), and the SOC concentration tended to increase with the increase in atmospheric oxidation. OC showed a good correlation with EC in all seasons, with the highest in autumn (R2 =0.9) and lower correlations in the other three seasons (R2 ranged from 0.74 to 0.75), indicating a common source. According to OC/EC ratio range, it was preliminarily determined that carbonaceous aerosol came from vehicle exhaust emissions, coal burning emissions, and biomass combustion emissions. In order to further quantify the contribution of major emission sources to carbonaceous aerosol, the results of this study using PMF to analyze the sources of carbonaceous aerosol showed that the main sources of carbonaceous aerosol in Huaxi District of Guiyang were coal combustion sources (29.3%), motor vehicle emission sources (21.5%), and biomass combustion sources (49.2%).

2.
Surg Radiol Anat ; 39(6): 601-610, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27866248

RESUMO

PURPOSE: To provide the anatomical basis of brachial plexus roots for the diagnosis and treatment of brachial plexus root avulsion injury. METHODS: The morphological features of brachial plexus roots were observed and measured on 15 cervicothoracic spine of adult cadavers. The relationship of brachial plexus nerve roots and the surrounding tissues also were observed, as well as the blood supply of anterior and posterior roots of the brachial plexus. RESULTS: Origination of the nerve roots in the dorsal-ventral direction from the midline was fine-tuned at each level along the spinal cord. The minimum distance of the origin of the nerve root to midline was 2.2 mm at C 5, while the maximum was 3.1 mm at T 1. Inversely, the distance between the origin of the posterior root and the midline of the spinal cord gradually decreased, the maximum being 4.2 mm at C 5 and minimum 2.7 mm at T 1. Meanwhile, there was complicated fibrous connection among posterior roots of the brachial plexus. The C 5-6 nerve roots interlaced with tendons of the scalenus anterior and scalenus medius and fused with the transverse-radicular ligaments in the intervertebral foramina. However, these ligaments were not seen in C 7-8, and T 1. The blood supply of the anterior and posterior roots of the brachial plexus was from the segmental branches of the vertebral artery, deep cervical artery and ascending cervical artery, with a mean outer diameter of 0.61 mm. CONCLUSIONS: The systematic and comprehensive anatomic data of the brachial plexus roots provides the anatomical basis to diagnose and treat the brachial plexus root avulsion injury.


Assuntos
Plexo Braquial/anatomia & histologia , Raízes Nervosas Espinhais/anatomia & histologia , Adulto , Plexo Braquial/irrigação sanguínea , Neuropatias do Plexo Braquial/cirurgia , Cadáver , Vértebras Cervicais/anatomia & histologia , Vértebras Cervicais/irrigação sanguínea , Humanos , Raízes Nervosas Espinhais/irrigação sanguínea , Vértebras Torácicas/anatomia & histologia , Vértebras Torácicas/irrigação sanguínea
3.
PLoS One ; 10(7): e0131696, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26148185

RESUMO

We aimed to investigate whether 1-deoxynojirimycin (DNJ) modulates glycometabolism and has toxicity in Eri silkworm (Samia cynthia ricini, Saturniidae). In this paper, hemolymph metabolites were used to explore metabolic changes after oral administration of DNJ or mulberry latex and to characterize the biological function of DNJ at the metabolic and systemic levels. Hemolymph samples were collected from fourth-instar larvae of Eri silkworm and ex-vivo high-resolution 1H nuclear magnetic resonance (NMR) spectra were acquired from the collected hemolymph samples. Then the obtained spectra were analyzed by principal component analysis (PCA) and independent-samples t-test. Metabolic pattern recognition analysis of hemolymph samples indicated that the groups of 0.25% DNJ, latex, and the mixture of 0.5% DNJ and latex (1:1) were significantly different from the control group. Moreover, compared to the control group, the groups of 0.25% DNJ, latex, and the mixture of 0.5% DNJ and latex (1:1) showed the decreased levels of citrate, succinate, fumarate, malate, and glutamine in hemolymph, the groups of 0.25% DNJ and the mixture of 0.5% DNJ and latex (1:1) showed the increased levels of trehalose and lactate. In addition, mulberry leaves exude latex was highly toxic to Eri silkworm because rich unidentified high-molecular-weight factor (s) acted as toxic substances. In our results, latex caused 20 deaths among 50 fourth-instar larvae of Eri silkmoth, but DNJ or the mixture did not caused death. All these results suggest that DNJ has a positive impact on the reverse glycometabolism by modulating glycometabolism and inhibiting glucogenesis and energy metabolism. DNJ is a secure substance as a single-ingredient antidiabetic medicine due to its nontoxicity and bioactivity.


Assuntos
1-Desoxinojirimicina/farmacologia , Bombyx/efeitos dos fármacos , Bombyx/metabolismo , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Metaboloma/efeitos dos fármacos , Metaboloma/fisiologia , Administração Oral , Animais , Larva/efeitos dos fármacos , Larva/metabolismo , Látex/farmacologia , Metabolômica/métodos , Morus/química , Folhas de Planta/química , Espectroscopia de Prótons por Ressonância Magnética/métodos
5.
Pharmazie ; 67(3): 242-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22530306

RESUMO

Ougan (Citrus suavissima Hort. ex Tanaka) is an important domesticated fruit which is used medicinally in China. To date, a number of methods for its identification and chemical analysis have been studied. However, the effects of Ougan juice on CYP isozymes have not been reported. Therefore, the objective of our study was to evaluate the potential effects of Ougan juice on the CYP isozymes CYP1A2, CYP2C9, CYP2C19 and CYP2D6 in rats using a cocktail approach involving the probe drugs phenacetin, tolbutamide, omeprazole and dextromethorphan. These four probe drugs were simultaneously administered to rats after single and multiple dosing of Ougan juice by gastric irrigation. The pharmacokinetics of the probes in the plasma were simultaneously determined by HPLC-MS. The main pharmacokinetic parameters of the four probe drugs were not significantly different in rats after single dose of Ougan juice. The t1/2 and AUC(0-infinity) of phenacetin and omeprazole increased significantly and their CL(z) decreased markedly after multiple dosing of Ougan juice. However, the t1/2 of tolbutamide decreased notably, while the t1/2 of dextromethorphan was not changed. The findings of this study suggest that a single administration of Ougan juice had little effect on P450 activities while multiple administration of Ougan juice tended to inhibit CYP1A2 and CYP2C19 and induce CYP2C9, but did not influence CYP2D6.


Assuntos
Bebidas , Citrus/química , Sistema Enzimático do Citocromo P-450/metabolismo , Interações Alimento-Droga , Animais , Área Sob a Curva , Calibragem , Cromatografia Líquida de Alta Pressão , Meia-Vida , Indicadores e Reagentes , Isoenzimas/metabolismo , Limite de Detecção , Masculino , Espectrometria de Massas , Preparações Farmacêuticas/metabolismo , Ratos , Ratos Wistar , Padrões de Referência , Análise de Regressão
6.
Phytochem Anal ; 22(5): 411-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21433157

RESUMO

INTRODUCTION: Metabonomic analysis is an important molecular phenotyping method for characterising plant ecotypic variations; hence, it may become a powerful tool for quality control and discrimination of traditional Chinese medicine (TCM). OBJECTIVE: To discriminate and assess the quality of Curcuma phaeocaulis, C. kwangsiensis and C. wenyujin from different ecotypes. The identification of the compositions of essential oils from the three Curcuma species was included in this study. METHODOLOGY: Metabolomics analysis was carried out on all samples by gas chromatography-mass spectrometry (GC-MS) coupled with multivariate statistical analysis. Characterisation of phytochemicals in essential oils was performed by automated matching to the MS library and comparison of their mass spectra (NIST05 database). RESULTS: Principal component analysis (PCA) effectively distinguished the samples from different species and ecotypes. Partial least squares discrimination analysis (PLS-DA) was successfully employed in classifying the GC-MS data of authentic, commercial and introduction cultivation samples. Furthermore, the components contributing significantly to the discrimination, namely curzerenone, germacrone, curdione and epicurzerenone, were screened by PCA and PLS-DA loading plots and further can be used as chemical markers for discrimination and quality control among different groups of samples.


Assuntos
Curcuma/química , Metabolômica/métodos , Óleos de Plantas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Análise dos Mínimos Quadrados , Análise Multivariada , Análise de Componente Principal , Rizoma/química
7.
Pharmazie ; 65(10): 720-2, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21105571

RESUMO

Hypertension has been recognized to be closely related to plasma homocysteine levels (tHcy). Spontaneously hypertensive rats (SHR) are used widely for hypertension research, but it is unclear whether hypertension is related to high levels of tHcy in rat plasma. To test whether hyperhomocysteinemia occurs in SHR we dynamically measured plasma total homocysteine (tHcy) in SHR by liquid chromatography-tandem mass spectrometry (LC-MS). This analytical method has good linearity within the range of 1-100 micromol/L for tHcy in rat plasma with a correlation coefficient of R = 0.9975. After dynamic monitoring (12 weeks) on the plasma tHcy in SHR and Wistar-Kyoto rats, we found that there was no significant difference in tHcy level between SHR and Wistar-Kyoto rats, which was 6.98 +/- 1.82 micromol/L and 8.04 +/- 1.64 micromol/L, respectively. And there was no significantly high level of plasma tHcy in SHR.


Assuntos
Homocisteína/sangue , Hipertensão/sangue , Animais , Calibragem , Cromatografia Líquida , Espectrometria de Massas , Monitorização Fisiológica , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Reprodutibilidade dos Testes
8.
Fa Yi Xue Za Zhi ; 25(2): 123-6, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19537253

RESUMO

OBJECTIVE: To develop a method for determination of clozapine, olanzapine and mirtazapine in human plasma by liquid chromatography-tandem mass spectrometry(LC-MS/MS). METHODS: Clozapine, olanzapine and mirtazapine were extracted from plasma samples by using diethyl ether and separated by Agilent Zorbax SB-C18 column(2.1 mm x 150 mm, 5 microm). Electrospray ionization source was applied, positive ion mode was used to detect and multiple reaction monitoring mode was used to quantify clozapine, olanzapine and mirtazapine. Carbamazepine was the internal standard. RESULTS: The detection limits of clozapine, olanzapine and mirtazapine were within 0.41-0.92 ng/mL. The calibration curve in the concentration range of 10.0-2000.0 ng/mL showed a good linear distribution (r > or = 0.992 4). The average extraction recoveries were within 65.7%-94.2%. Intra-day RSD and inter-day RSD were less than 6% (n = 5). CONCLUSION: This method seems to be quite specific, sensitive and accurate, and can be used to detect clozapine, olanzapine and mirtazapine in forensic and clinical analytic toxicology.


Assuntos
Benzodiazepinas/sangue , Cromatografia Líquida , Clozapina/sangue , Mianserina/análogos & derivados , Espectrometria de Massas em Tandem , Cromatografia Líquida/métodos , Toxicologia Forense , Humanos , Mianserina/sangue , Mirtazapina , Olanzapina , Espectrometria de Massas em Tandem/métodos
9.
Zhongguo Zhong Yao Za Zhi ; 33(18): 2056-60, 2008 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19160782

RESUMO

Gas chromatography/mass spectrometry, chemometric resolution method-Alternative movingwindow factor analysis that were proposed recently and the Kovats retention index were used to analyze the essential components of herbal pair Cinnamomum cassia Presl and Poria cocos (CCP-PC) and compare them with those of single herbal Cinnamomum cassia Presl (CCP). 46 and 42 essential components in essential oil of CCP and CCP-PC have been identified individually. Results shows that the number of essential components of CCP and CCP-PC were almost the same, but extractive ratioes of them have changed significantly, some of them were increased obviously, most of them were declined notably instead and even several ingredients of CCP-PC were disappeared due to CCP PC's interaction probably. The main pharmacodynamic ingredients of CCP-PC, 3-phenyl-2-propenal and Cinnamaldehyde were obviously higher contents than that of single CCP. It suggested that there exist certain interactions of the chemical ingredients in compound medicine rather than their sum effect of single medicines. There is a litter difference in quality and quantity between single medicines and pair medicines, so the application of pair medicines can expand single medicine's adaptive disease and has a good clinical referenced valuation.


Assuntos
Cinnamomum aromaticum/química , Medicamentos de Ervas Chinesas/química , Poria/química , Cromatografia Gasosa-Espectrometria de Massas
10.
Fen Zi Xi Bao Sheng Wu Xue Bao ; 39(2): 103-10, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16944580

RESUMO

Polysaccharide and lipid in the anthers of Lycium barbarurn L. at different stages were examined with cytochemical techniques. At the stage of sporogenous cell, many starches have been storied in parenchyma around vascular bundle, epidermis and endothecium cells but no starches in sporogenous cells, tapetal and middle layer cells. At the stage of tetrad, there were many starches still in epidermis and endothecium, however tapetal cells began to accumulate lipid drops, suggesting that tapetal cells transformed polysaccharides into lipid. Tapetum degenerated at the late stage of microspore and the lipid drops moved into locule. During microspore development neither starches nor lipid drops were accumulated in the cell. After the division of microspore, some lipids drops appeared in 2-cellular pollen, and then some starches also appeared in the pollen. Two days before anthesis, there were many lipid drops and starches located in nearly mature pollen grains, suggesting that pollen of Lycium barbarurn L. has a function of transforming lipid into polysaccharide. The temporal and spatial features of polysaccharide and lipid material accumulated and distributed in anther during its development reflect the transformation of physiological function of the cells consisting of anther. This research will help us to understand the mechanism of anther development.


Assuntos
Flores/metabolismo , Metabolismo dos Lipídeos , Lycium/metabolismo , Pólen/metabolismo , Polissacarídeos/metabolismo , Flores/citologia , Flores/crescimento & desenvolvimento , Gametogênese , Lycium/citologia , Lycium/crescimento & desenvolvimento , Pólen/citologia , Pólen/crescimento & desenvolvimento
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