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1.
Ying Yong Sheng Tai Xue Bao ; 28(4): 1326-1336, 2017 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-29741331

RESUMO

The expansion of built-up area will cause stress effect on the regional natural ecological security pattern during urbanization process. Taking rapid expanding regions of four inland and coastal cities as study areas, including Tongzhou in Beijing, Zhengding in Hebei, Tanggu in Tianjin and Xiamen in Fujian, we constructed regional landscape stress indexes according to the principle of landscape ecology and comparatively analyzed the landscape pattern characteristics of rapid expanding regions and the differences of stress effect of artificial landscapes on four natural landscapes ecological security pattern in the process of rapid urbanization. Results showed that landscape erosion indexes of Tongzhou, Zhengding, Tanggu and Xiamen in 2015 were 1.039, 0.996, 1.239 and 0.945, respectively, which indicated that the natural landscapes were eroded significantly. Natural landscape types of those four regions presented different threatened levels. Among all natural landscape types, unused land and waters were worst threatened in Tongzhou, Zhengding and Tanggu, while in Xiamen cultivated land and waters showed the highest threat levels. The waters threat indexes of those four areas were all more than 0.743. Landscape isolation indexes of waters and unused land of the inland cities were greater than those of coastal cities, which meant water distribution of inland cities in the space was less gathered than that of coastal cities. Besides, compared with the other natural landscape, unused land and waters suffered the largest stress from artificial landscapes.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Urbanização , Pequim , China , Cidades , Ecologia
2.
Cancer Sci ; 100(2): 216-24, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19068094

RESUMO

N,N'-Dinitrosopiperazine (DNP) induces nasopharyngeal carcinoma (NPC) and shows organ specificity to the nasopharyngeal epithelium. To investigate its mechanism, the rat NPC model was induced using DNP. Rat NPC and normal nasopharyngeal cells were obtained from the NPC model using laser capture. The total proteins from these cell samples were separated with two-dimension polyacrylamide gel electrophoresis techniques, and highly expressed proteins (> five-fold) were analyzed using matrix-assisted laser desorption/ionization time of flight and bioinformatics. The results showed that HSP70 and mucin 5B expression increased not only in rat NPC but also in atypical hyperplasia nasopharyngeal tissues, a precancer stage of NPC. High-expression of heat shock protein 70 (HSP70) and mucin 5B was further supported by western blot analysis. The immunofluorescence and western-blotting studies further showed that DNP induced the expression of HSP70 and mucin 5B in a dosage-dependent manner in normal nasopharyngeal epithelia cells. Our data indicate that DNP triggers over-expression of HSP70 and mucin 5B, and is involved in nasopharyngeal tumorigenesis. HSP70 and mucin 5B may be important targets in nasopharyngeal tumorigenesis induced by DNP.


Assuntos
Carcinógenos/toxicidade , Proteínas de Choque Térmico HSP70/metabolismo , Mucina-5B/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Lesões Pré-Cancerosas/metabolismo , Animais , Western Blotting , Proliferação de Células , Eletroforese em Gel Bidimensional , Feminino , Imunofluorescência , Masculino , Neoplasias Nasofaríngeas/induzido quimicamente , Neoplasias Nasofaríngeas/patologia , Nitrosaminas/toxicidade , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/patologia , Proteômica , Ratos , Ratos Wistar , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
3.
Artigo em Inglês | MEDLINE | ID: mdl-18296129

RESUMO

A sensitive, rapid liquid chromatographic-electrospray ionization mass spectrometric method for determination of erythromycylamine in human plasma was developed and validated. Erythromycylamine in plasma (0.2 mL) was extracted with ethyl acetate, the organic phase was transferred to another clear 1.5 mL Eppendorf tube and evaporated to dryness under gentle nitrogen stream at 45 degrees C, and the residue was dissolved in 100 microL of mobile phase. The samples were separated using a Thermo Hypersil HyPURITY C18 reversed-phase column (150 mm x 2.1 mm I.D., 5 microm). A mobile phase containing 10 mM of ammonium acetate (pH = 6.4)-acetonitrile-methanol (50:10:40, v/v/v) was used isocratically eluting at a flow rate of 0.2 mL/min. Erythromycylamine and its internal standard (IS), midecamycin, were measured by electrospray ion source in positive selective ion monitoring mode. The method demonstrated that good linearity ranged from 4.5 to 720 ng/mL with r = 0.9997. The limit of quantification for erythromycylamine in plasma was 4.5 ng/mL with good accuracy and precision. The mean extraction recovery of the method was higher than 75.1% and 72.7% for erythromycylamine and IS, respectively. The intra-day and inter-day precision ranged from 5.2% to 6.4% and 5.6-9.3% (relative standard deviation, RSD), respectively. The established method has been successfully applied to a bioequivalence study of two dirithromycin formulations for 18 healthy volunteers.


Assuntos
Antibacterianos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Eritromicina/análogos & derivados , Espectrometria de Massas por Ionização por Electrospray/métodos , Adulto , Estabilidade de Medicamentos , Eritromicina/sangue , Eritromicina/farmacocinética , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Equivalência Terapêutica
4.
J Pharm Biomed Anal ; 42(4): 480-7, 2006 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-16822633

RESUMO

A sensitive, rapid liquid chromatographic-electrospray ionization mass spectrometric method for determination of azithromycin in human plasma was developed and validated. Azithromycin in plasma (0.2mL) was extracted with methyl tert-butyl ether-hexane (50:50, v/v), organic phase was transferred to another clear 1.5mL Eppendorf tube and evaporated to dryness at 40 degrees C and dissolved in mobile phase, samples were separated using a Thermo Hypersil HyPURITY C18 reversed-phase column (150mmx2.1mm i.d., 5microm), together with a mobile phase containing of 20mM ammonium acetate (pH 5.2)-acetonitrile-methanol (50:40:10, v/v/v) and was isocratically eluted at a flow rate of 0.2mL/min. Azithromycin and its internal standard, clarithromycin, were measured by electrospray ion source in positive selective ion monitoring mode. The method demonstrated that good linearity ranged from 2 to 1000ng/mL with r=0.9977. The limit of quantification for azithromycin in plasma was 2ng/mL with good accuracy and precision. The higher mean extraction recovery, say 81.2% and 75.5% for azithromycin and internal standard (IS), respectively, was obtained in this work. The intra-day and inter-day precision ranged from 4.8% to 8.6% and 6.4% to 10.7% (R.S.D.), respectively. The established method has been successfully applied to bioequivalence study of 2 azithromycin formulations for 24 healthy volunteers.


Assuntos
Azitromicina/química , Azitromicina/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Administração Oral , Adulto , Antibacterianos/química , Antibacterianos/farmacocinética , Azitromicina/administração & dosagem , Azitromicina/sangue , Claritromicina/química , Claritromicina/farmacocinética , Humanos , Masculino , Reprodutibilidade dos Testes , Equivalência Terapêutica
5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 29(5): 577-82, 2004 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16137052

RESUMO

OBJECTIVE: To investigate the inhibitory mechanism of Yiqijiedu granule on the implanted-tumor growth of nasopharyngeal carcinoma in nude mice. METHODS: Twenty nude mice were injected nasopharyngeal carcinoma cells (HNE1), with 5 x 10(6) cells for a nude mouse. Implanted-tumors grew for 20 d, whose volume reached 1 cm x 1 cm x 1 cm. These nude mice were divided into 2 groups: Yiqijiedu group and control group. The Yiqijiedu group was given Yiqijiedu granule, and the control was given normal saline for 30 d, and then were killed. The volume and weight of implanted-tumors were measured. A 100-mg tissue from implanted-tumors was used to extract total protein by current methods, in which the proteins were separated by two-dimension electrophoresis and stained by silver, and protein profiles of implanted-tumors were obtained. Different proteins in the profiles were analyzed by ImageMaster 2D Elite 4.01. Nineteen different proteins, in which 4 expressed in the Yiqijiedu group, 4 expressed in the control, and the other 11 were differently expressed at 5 folds, were identified by MALDI-TOF-MS. RESULTS: The Yiqijiedu granule could inhibit the growth of implanted-tumors. The volume and weight of implanted-tumors in the Yiqijiedu group were (0.207 +/- 0.023) cm3 and (0.132 +/- 0.021) g respectively, and that of the control was (1.342 +/- 0.298) cm3 and (1.017 +/- 0.015) g ( P < 0.05). The inhibitory rate was 84.58%. The analyses of two-dimension electrophoresis and ImageMaster 2D Elite 4.01 showed that there were 567 +/- 49 protein dots in the Yiqijiedu group and 679 +/- 59 in the control. We found 243 proteins were dys-regulated, of which 112 proteins were observed, up-regulated and the other 131 proteins were down-regulated. MALDI-TOF-MS and Database analysis showed that the high expression proteins were HKR2 protein, 10 Phosphoribosyl pyrophosphate synthetase, TNFR superfamily member, and Apoptosis regulator. The lower expression proteins were Fibulin-3, Zinc finger protein 266, Carboxy terminus of HSP70-interacting protein, et al. CONCLUSION: Yiqijiedu granule could inhibit the growth of nasopharyngeal carcinoma, which may be associated with those proteins regulated by itself.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Nasofaríngeas/tratamento farmacológico , Proteínas de Neoplasias/biossíntese , Animais , Regulação para Baixo , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Transplante de Neoplasias
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