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1.
Pak J Pharm Sci ; 36(1): 89-97, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36967501

RESUMO

Development of adjuvant chemotherapy drugs against drug-resistant lung cancer cells is necessary. The use of non-toxic adjuvant natural product combined with chemotherapy drugs will be an important treatment mode in the future. The purpose of the study investigates that fucoidan enhances chemotherapy drug poisoning drug-resistant lung cancer cell. Drug-resistant lung cancer cells are established in the study. Cell culture, MTT assay, wound healing assay, gelatin zymography assay, DNA fragmentation assay, apoptosis assay, reverse transcription polymerase chain reaction (RT-PCR) western blot analysis was adopted. The results showed that fucoidan synergized with doxorubicin increased efficacy of poisoning drug-resistant lung cancer cells and enhanced the ability of doxorubicin to inhibit the migration of drug-resistant lung cancer cells. It was observed that fucoidan synergized with doxorubicin induced the increase of apoptosis and inhibited expression of MMP-9, LC3, Beclin-1 and ß-catenin in drug-resistant lung cancer cells. Fucoidan synergized with doxorubicin significantly inhibited proliferation, migration and metastasis of drug-resistant lung cancer cells. Fucoidan strengthened doxorubicin to induce apoptosis and autophagy of drug-resistant lung cancer cells. This study confirms that the combined use of fucoidan and chemotherapeutic drugs can effectively poison drug-resistant lung cancer cells.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Apoptose , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Proliferação de Células , Linhagem Celular Tumoral
2.
Postepy Dermatol Alergol ; 38(3): 396-403, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34377119

RESUMO

INTRODUCTION: Beta2-adrenoceptors regulate proliferation of keratinocytes. Nitric oxide (NO) produced by keratinocytes through stimulation of nitric oxide synthase (NOS) mediates keratinocyte proliferation. Aim: In this study, the mechanism interaction ß-ARs and NO production on keratinocyte will be explored, and the important for proliferation will be studied. MATERIAL AND METHODS: To understand the relationship among ß2-adrenoceptors, NO production and proliferation in keratinocytes, the experiment is divided to two parts. In the first part of the experiment, keratinocytes are divided into five groups which are treated with 0 M, 10-7 M, 10-6 M, 5 × 10-6 M and 10-5 M isoproterenol, respectively. In the second part of the experiment, the keratinocytes are divided into five groups which are treated with 10-5 M isoproterenol and L-NMMA at doses of 0 M, 10-6 M, 5 × 10-6 M, 10-5 M and 5 × 10-5 M, respectively. We examine NOS expression, NO production, c-AMP level and proliferation in human keratinocytes. RESULTS: The results show that isoproterenol results in iNOS and ncNOS protein raised and the elevation of nitric oxide. L-NMMA can block the increase of iNOS and ncNOS protein expression and the ability to inhibit proliferation caused by isoproterenol. CONCLUSIONS: Beta2-adrenergic receptor agonist mediates nitric oxide synthase to affect keratinocyte proliferation in skin. The physiological and pathological relationship of these discoveries remains to be defined. These results can provide new possibilities in the therapy of integumentary disease conditions linked with the dysfunction of ß-AR-mediated NO production.

3.
Toxicol In Vitro ; 42: 101-104, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28412505

RESUMO

UVB is a potent modulator of cell growth and differentiation in the skin. The UVB irradiation has been used in treating hyperproliferative dermatoses. Otherwise, UVB radiation is also the major risk factor for developing skin cancer. Nitric oxide (NO) has been suggested to be a physiological modulator of cell proliferation. Raf-1 kinase inhibitory protein (RKIP) was involved in cell growth, transformation, and differentiation. The purpose of this study was to search for the possible cause of UVB-inhibited hyperplasia and UVB-resulted hyperproliferation. We evaluated various UVB dose whether affect the expression of RKIP, iNOS, NO and proliferation in keratinocyte. Normal human keratinocytes were treated with UVB dose of 40mJ/cm2, 80mJ/cm2, 120mJ/cm2, 160mJ/cm2 and 0mJ/cm2 (control group) respectively. The results showed that RKIP, iNOS and NO of keratinocytes with doses of 40mJ/cm2 and 80mJ/cm2 UVB treatment significantly higher than control group (P<0.01). The proliferation of keratinocyte with doses of 40mJ/cm2 and 80mJ/cm2 UVB treatment was significantly lower than control group (P<0.01). However, RKIP, iNOS and NO of keratinocytes with doses of 120mJ/cm2 and 160mJ/cm2 UVB treatment significantly lower than control group (P<0.01). The proliferation of keratinocyte with doses of 120mJ/cm2 and 160mJ/cm2 UVB treatment was significantly higher than control group (P<0.01). In conclusion, these results showed that the different UVB dosages induced various alteration of RKIP, NO, iNOS and proliferation may provide important information on the therapeutic molecular mechanism of UVB-inhibited hyperplasia and UVB resulted hyperproliferation.


Assuntos
Queratinócitos/efeitos da radiação , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Raios Ultravioleta , Proliferação de Células/efeitos da radiação , Células Cultivadas , Humanos , Queratinócitos/metabolismo
4.
Environ Toxicol ; 32(3): 1079-1082, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27255443

RESUMO

Arsenic is associated with cancers of kidney and liver. Raf kinase inhibitor protein (RKIP) has been identified as a member of a novel class of molecules that suppress the metastatic spread of tumors. In order to investigate the effect of arsenic to RKIP of liver and kidney, the expression of RKIP of liver and kidney with As (III) was explored in this study. Thirty male mice were chronically fed with 42.5 ppm, 85 ppm NaAsO2 and water for 180 days. The kidney and liver accumulation levels of As (III) in mice were determined by electro-thermal atomic absorption spectrometry. The method of RT-PCR, Western blotting analysis and immunohistochemistry were used to determine gene expression and protein expression of RKIP. The results showed that arsenic level was significantly increased in kidney and liver of As (III)-exposed mice as compared with control group. The gene expression and protein expression of RKIP was significantly decreased in kidney and liver of As (III)-exposed mice in comparison with these of control mice. These data suggested that RKIP decrease of liver and kidney with As (III) may be dangerous index in formation of cancer. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1079-1082, 2017.


Assuntos
Arsênio/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Proteína de Ligação a Fosfatidiletanolamina/genética , Animais , Intoxicação por Arsênico/genética , Intoxicação por Arsênico/metabolismo , Intoxicação por Arsênico/patologia , Western Blotting , Regulação da Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Rim/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
J Appl Toxicol ; 31(8): 730-40, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21437922

RESUMO

Hexavalent chromium (CrVI) is considered to be a risk factor in the formation of human cancer. Raf kinase inhibitor protein (RKIP), Rho-GDIα, galectin, c-Myc and p53 play important roles in cancer formation. The purpose of this study was to determine if Cr(VI) induces the formation of gastrointestinal cancer. We explored the expression of RKIP, Rho-GDIα, galectin, c-Myc and p53 in the colon and stomach in rats exposed to chromium (CrVI). Thirty Wistar rats were divided into six groups which were chronically fed with 250, 500, 750, 1000 and 1250 ppm Na(2) Cr(2) O(7) and water for 60 days. The level of Cr(VI) was determined by electrothermal atomic absorption spectrometry. The expression of RKIP, Rho-GDIα, galectin, c-Myc and p53 of stomach and colon was measured by western blot. The gene expression of RKIP, Rho-GDIα, galectin, c-Myc and p53 of the stomach and colon was determined by RT-PCR. The results showed that the expression of p53 and Rho-GDIα was decreased in the stomach and colon of rats with Cr(VI) treatment. The expression of RKIP was decreased in the stomach and colon of rats treated with high-dose Cr(VI). The expression of c-Myc and gelectin-1 was increased in the stomach and colon of rats with Cr(VI) treatment. We concluded that the anomalous expression of RKIP, Rho-GDIα, galectin, c-Myc and p53 might be a dangerous index of cancer formation in the stomach and colon of rats with Cr(VI) exposure.


Assuntos
Cromo/toxicidade , Galectinas/genética , Trato Gastrointestinal/efeitos dos fármacos , Inibidores de Dissociação do Nucleotídeo Guanina/genética , Proteína de Ligação a Fosfatidiletanolamina/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteína Supressora de Tumor p53/genética , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Galectinas/metabolismo , Trato Gastrointestinal/patologia , Regulação da Expressão Gênica , Inibidores de Dissociação do Nucleotídeo Guanina/metabolismo , Masculino , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ratos , Ratos Wistar , Espectrofotometria Atômica , Proteína Supressora de Tumor p53/metabolismo , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho , Inibidores da Dissociação do Nucleotídeo Guanina rho-Específico
6.
Toxicol In Vitro ; 25(1): 1-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20600800

RESUMO

BACKGROUND: Chromium (Cr) is considered to be a risk factor to the cardiovascular effects of fine particulate matter components to PM2.5 from traffic in highway patrol officers. RKIP (raf kinase inhibitor protein) is a physiological inhibitor of GRK-2 (G-protein-coupled receptor kinase 2) and affects ß-adrenergic signaling and contractile activity in cardiomyocytes. OBJECTIVES: In this study, we explored the change of RKIP in heart of chromium (VI)-exposed rats and cultured myocardial cells with chromium (VI) treatment. METHOD: Wistar rats were divided into six groups which were chronically fed with 250, 500, 750, 1000, and 1250 ppm Na(2)Cr(2)O(7) and water for 60 days, respectively. Na(2)Cr(2)O(7) dose of 0.25, 0.5, 1.5, 3, 4.5, and 0 ppm (control group) was applied in cultured myocardial cells. The level of heart Cr (VI) was determined by electrothermal atomic absorption spectrometry. The expression of RKIP was measured by Western blot method. The MTT assay was used to measure the toxicity of myocardial cells with Cr (VI) treatment. The apoptosis test of myocardial cells was determined by caspase-3 colorimetric assay kit. RESULT: The result showed that the expression of RKIP in heart (in vivo) and myocardial cells (in vitro) was decreased following Cr (VI) dose-dependent treatment. CONCLUSION: We suggested that the decrement of RKIP of heart and myocardial cells with Cr (VI) treatment resulted in the function of cardiovascular system decreased.


Assuntos
Poluentes Atmosféricos/toxicidade , Compostos de Cromo/toxicidade , Regulação para Baixo/efeitos dos fármacos , Coração/efeitos dos fármacos , Miocárdio/metabolismo , Poluentes Atmosféricos/farmacocinética , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromatos/administração & dosagem , Cromatos/farmacocinética , Cromatos/toxicidade , Cromo/análise , Compostos de Cromo/administração & dosagem , Compostos de Cromo/farmacocinética , Relação Dose-Resposta a Droga , Coração/crescimento & desenvolvimento , Masculino , Miocárdio/química , Miocárdio/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Material Particulado/toxicidade , Ratos , Ratos Wistar , Distribuição Tecidual
7.
DNA Cell Biol ; 29(6): 285-93, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20482226

RESUMO

Chemotherapy is an important postsurgery adjuvant therapy in the treatment of breast cancer. However, because of the individual genotype differences of patients, the drug efficacy differs from person to person, even when the same chemotherapy drug is administered. The purpose of this research was to probe the gene expression profiles to predict the efficacy of 5-fluorouracil (5-FU), the common drug used in chemotherapy for various type of cancers, in Taiwanese breast cancer patients. Microarray analysis was conducted on the cancer cell line ZR-75-1 with and without 5-FU stimulation to identify the differentially expressed genes. The significant overexpressed gene groups were selected after bioinformatics software analysis to explore the molecular mechanism of 5-FU. Six strains of breast cancer cell line purchased from American Type Culture Collection were used to analyze the expression profiles of the above target gene groups. IL18, CCL28, CXCL2, SOD1, HRAS, FDXR, and CHI3L1 genes were significantly differentially expressed in 5-FU responder and nonresponder cell lines. The selected gene groups were validated with 20 strains of breast cancer primary cultures established previously in our laboratory. The experimental results demonstrated that FAM46A, IL18, CCL28, TNF, CXCL2, PLEKHA8, HRAS, FDXR, and CHI3L1 genes showed statistically significant differential expression between primary breast cancer culture cells that respond and nonrespond to 5-FU. Six genes, IL18, CCL28, CXCL2, HRAS, FDXR, and CHI3L1, showed significant differential expression pattern in both American Type Culture Collection and primary breast cancer cultured cells. The findings of this study may serve as basis for predicting the effectiveness of 5-FU on breast cancer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/genética , Fluoruracila/farmacologia , Perfilação da Expressão Gênica , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Neoplásicos/genética , Humanos , Concentração Inibidora 50 , Análise de Sequência com Séries de Oligonucleotídeos , Reprodutibilidade dos Testes
8.
Lung Cancer ; 68(1): 51-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19589613

RESUMO

Activating mutation of the K-ras gene was one of the earliest discoveries of genetic alterations in lung cancer. Moreover, K-ras somatic mutations might be suggested for predicting resistance to molecular antibodies targeting the epidermal growth factor receptor (EGFR). However, activated K-ras mutant detection methods are limited to traditional techniques. The techniques are complicated and are used only in tissue samples, which are limited for clinical applications. In a previous study, we established a low-cost, convenient, and easy technique for detecting activated K-ras in a small number of circulating tumor cells by the colorimetric membrane array method (CLMA). However, the sensitivity still needs further improvement. The aim of this study is to develop a new platform with chemiluminescence as reporter and weighted values of target genes on the chip in order to achieve a more sensitive, easier to read, and more accurate platform-weighted chemiluminecent membrane array (WCHMA). In advance, we collected 209 peripheral blood samples of non-small cell lung cancer (NSCLC) from patients to evaluate clinical K-ras activation detection using Activating KRAS Detection Chip both conducted by CLMA and WCHMA. Results show 71 specimens with K-ras mutation, of which 59 were identified as positive through CLMA and 66 were positive through WCHMA. After statistical analysis, the sensitivity of CLMA was found to be 83% and the specificity was 96%. On the other hand, the sensitivity of WCHMA increased to 93% and the specificity remained at 94%. Results of the detection limitation of peripheral blood on two platforms are: 3cancer cells/cm(3) blood using WCHMA, which is better than 5cancer cells/cm(3) blood using CLMA. Further analysis on the correlation between the test results and clinical pathological features shows that the mean score obtained using WCHMA is significantly correlated to TNM stage, tumor size, and metastasis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Colorimetria/métodos , Genes ras/genética , Medições Luminescentes , Neoplasias Pulmonares/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Progressão da Doença , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/fisiopatologia , Metástase Neoplásica , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Sensibilidade e Especificidade , Análise Serial de Tecidos/métodos
9.
Ann Surg Oncol ; 17(2): 624-33, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19937133

RESUMO

BACKGROUND: In 2008, the National Comprehensive Cancer Network suggested conducting a KRAS mutations test in metastatic colorectal cancer (mCRC) patients prior to administering therapy that uses anti-epidermal growth factor receptor (EGFR) monoclonal antibody. However, tests of KRAS mutations have been limited when traditional molecular techniques, such as polymerase chain reaction (PCR) combined direct sequencing, are used to obtain and analyze patients' cancer tissues. If the primary tumor or metastatic tissues of patients with mCRC is unavailable, then such analysis will not be feasible. Our laboratory has successfully established a colorimetric membrane array analysis platform that could detect activating KRAS mutations from the peripheral blood of patients with various malignancies. METHODS: The current research aims to improve the above-mentioned technique not only by using chemiluminescence detection to replace color development, but also to add scores weighted according to the relevance of each gene to activating KRAS mutations. RESULTS: Our results show that the described weighted chemiluminescent membrane array (WCHMA) can detect circulating tumor cells (CTCs) harboring activating KRAS mutations in the peripheral blood in CRC. The sensitivity, specificity, and accuracy were 90.2, 94.9, and 93.5%, respectively, and the detection limitation was three colon tumor cells per millimeter of blood. The current study would significantly improve the detection sensitivity and accuracy over that of our previously designed membrane array method. CONCLUSIONS: These findings also highlight the need to prompt further prospective studies on more cases of CRC to further establish the clinical relevance of activating KRAS mutation detection from peripheral blood in anti- EGFR-based chemotherapy that uses activating KRAS detection chips and the WCHMA analysis method.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Perfilação da Expressão Gênica , Células Neoplásicas Circulantes/metabolismo , Proteínas Proto-Oncogênicas/sangue , Proteínas ras/sangue , Idoso , Biomarcadores Tumorais/genética , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Colorretais/genética , Feminino , Humanos , Luminescência , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Membranas Artificiais , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Sensibilidade e Especificidade , Proteínas ras/genética
10.
Exp Dermatol ; 18(6): 571-3, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19228192

RESUMO

Several reports have focused on the potential of nitric oxide (NO) to influence the proliferation and differentiation cascade in a number of mammalian cells. The purpose of this study was to determine the relationship between expression of raf kinase inhibitor protein (RKIP) and proliferation in keratinocyte with NO treatment. Normal human keratinocytes were treated with SNAP (NO donor) doses of 10(-7), 10(-6), 10(-5), 10(-4) and 0 m (control group) separately. Expression of protein and mRNA of RKIP, cell proliferation and apoptosis have been measured. These results showed that elevated expression of RKIP in keratinocyte with NO treatment may contribute to the pathological and physiological features of NO-inhibited proliferation.


Assuntos
Queratinócitos/efeitos dos fármacos , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico/fisiologia , Proteína de Ligação a Fosfatidiletanolamina/biossíntese , S-Nitroso-N-Acetilpenicilamina/farmacologia , Apoptose/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Relação Dose-Resposta a Droga , Humanos , Queratinócitos/metabolismo , Masculino , Doadores de Óxido Nítrico/administração & dosagem , Proteína de Ligação a Fosfatidiletanolamina/genética , S-Nitroso-N-Acetilpenicilamina/administração & dosagem
11.
Cancer Lett ; 233(1): 165-71, 2006 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-15905022

RESUMO

It has been reported that the mutational inactivation of the adenomatous polyposis coli (APC) and beta-catenin genes play important roles in colorectal carcinogenesis. However, alteration of the components in the Wnt signaling pathway in colorectal cancer (CRC) with microsatellite instability (MSI) has been elucidated. To define the precise role of the Wnt signaling components in CRC and leukemia cell lines with MSI, mutational analyses of the T cell factor 4 (TCF4) genes were performed. Here we describe for the first time a TCF4 MSI+ phenotype in leukemia cell lines except in colon cancer cell lines. Moreover, we found that these cell lines exhibited deletion and insertion of 1-2A in an (A)9 repeat so as to result in (A)7, (A)8, (A)10 and (A)11 repeat, respectively. To characterize the cellular function of these special TCF4 mutant clones, transient transfection and fluorescent microscopy were analyzed and the results revealed that the TCF4 frameshift gene products all localized in nuclei. Surprisingly, these TCF4 frameshift mutants lost transcriptional activity with beta-catenin and down-regulate the target gene expression. These results delineate a novel role for MSI+TCF4 in leukemia and colon cancer progression.


Assuntos
Neoplasias do Colo/genética , Instabilidade Genômica , Leucemia/genética , Repetições de Microssatélites , Fatores de Transcrição TCF/genética , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Humanos , Leucemia/patologia , Mutação , Proteína 2 Semelhante ao Fator 7 de Transcrição , Transcrição Gênica , beta Catenina/genética , beta Catenina/fisiologia
12.
Bioconjug Chem ; 16(5): 1225-31, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16173802

RESUMO

Covalent attachment of poly(ethylene glycol) (PEG) molecules to drugs, proteins, and liposomes is a proven technology for improving their bioavailability, safety, and efficacy. Qualitative and quantitative analysis of PEG-derivatized molecules is important for both drug development and clinical applications. We previously reported the development of a monoclonal IgM antibody (AGP3) to PEG. We now describe a new IgG1 monoclonal antibody (E11) to PEG and show that it can be used in combination with AGP3 to detect and quantify PEG-derivatized molecules. Both antibodies bound the repeating subunits of the PEG backbone and could detect free PEG and PEG-modified proteins by ELISA, immunoblotting, and flow cytometry. Detection sensitivity increased with the length and the number of PEG chains on pegylated molecules. Both antibodies also efficiently accelerated the clearance of a PEG-modified enzyme in vivo. A sandwich ELISA in which E11/AGP3 were employed as the capture/detection antibodies was developed to detect PEG-modified proteins at concentrations as low as 1.2 ng/mL. In addition, the ELISA could also quantify, in the presence of 10% fetal bovine serum, free methoxy-PEG20,000, PEG2,000-quantum dots, and PEG2,000-liposomes at concentrations as low as 20 ng/mL (1.0 nM), 1.4 ng/mL (3.1 pM), and 2.4 ng/mL (3.13 nM phospholipids), respectively. Finally, we show that the sandwich ELISA could accurately measured the in vivo half-life of a PEG-modified enzyme. These antibodies should be generally applicable to the qualitative and quantitative analysis of all PEG-derivatized molecules.


Assuntos
Anticorpos Monoclonais/imunologia , Lipossomos/análise , Lipossomos/química , Nanoestruturas/análise , Polietilenoglicóis/química , Proteínas/análise , Proteínas/química , Animais , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Feminino , Lipossomos/imunologia , Camundongos , Proteínas/imunologia
13.
Food Chem Toxicol ; 43(7): 1117-26, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15833387

RESUMO

Liriodenine was isolated from the leaves of Michelia compressa. This study was designed to assess cell cycle arrest, the production of nitric oxide (NO) and p53 expression in liriodenine-treated human hepatoma cell lines, including wild-type p53 (Hep G2 and SK-Hep-1). As evidenced by flowcytometric studies, liriodenine induced cell cycle G(1) arrest and inhibited DNA synthesis in Hep G2 and SK-Hep-1 cell lines. The p53, iNOS expression and intracellular NO level were markedly increased in Hep G2 cells after liriodenine treatment. A NO inhibitor, carboxy-PTIO inhibited the p53 expression induced by liriodenine. In addition, liriodenine could not induce obvious cytotoxicity in normal human IMR-90 cell line. These results demonstrate that NO production and p53 expression are critical factors in liriodenine-induced growth inhibition in human wild-type p53 hepatoma cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Aporfinas/farmacologia , Carcinoma Hepatocelular/patologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Genes p53/efeitos dos fármacos , Óxido Nítrico/fisiologia , Antimetabólitos , Antineoplásicos Fitogênicos/química , Aporfinas/química , Western Blotting , Bromodesoxiuridina , Cromatografia em Camada Fina , DNA de Neoplasias/biossíntese , Relação Dose-Resposta a Droga , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Magnoliaceae/química , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase Tipo II , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Células Tumorais Cultivadas
14.
Toxicology ; 207(1): 73-80, 2005 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-15590123

RESUMO

For understanding a reversible or irreversible harm of beta-adrenergic system in lead induced cardiovascular disease (hypertension), We set up animal model to estimate the change of blood pressure and sympathetic nervous system after lead exposure withdrawn in the study. We address three topics in this study: (a) the relationship between withdrawal time of lead exposure and beta-adrenergic receptor, plasma catecholamine level, blood pressure, and lead level in heart, aorta, and kidney in lead-induced hypertensive rats after lead exposure stopped; (b) the relationship between blood pressure and beta-adrenergic receptor in heart, aorta, and kidney; (c) the estimation of relationship between lead withdrawn and the variation of beta-adrenergic system. Wistar rats were chronically fed with 2% lead acetate (experimental group) and water (control group) for 2 months. The rats were divided into 8 groups by withdrawal time of lead exposure stopped. Plasma catecholamine level was measured by high-performance liquid chromatography. Radioligand binding assay was measured by a method that fulfilled strict criteria of beta-adrenergic receptor using the ligand [125I]iodocyanopindolol. The levels of lead were determined by electrothermal atomic absorption spectrometry. The results showed that a close relation between reduced lead level and the plasma catecholamine level decreased, aorta beta-adrenergic receptor increased, kidney beta-adrenergic receptor diminished, heart beta-adrenergic receptor increased, and blood pressure dropped after lead exposure withdrawn. The study on the regulation of beta-adrenergic system in lead-induced hypertension after lead withdrawn might also provide insight about the nature of this disease state.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Hipertensão/induzido quimicamente , Compostos Organometálicos/toxicidade , Receptores Adrenérgicos beta/metabolismo , Administração Oral , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Catecolaminas/sangue , Modelos Animais de Doenças , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Miocárdio/metabolismo , Compostos Organometálicos/farmacocinética , Ligação Proteica , Ensaio Radioligante , Ratos , Ratos Wistar , Distribuição Tecidual
15.
Arch Toxicol ; 79(1): 1-6, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15502967

RESUMO

To understanding the reversible or irreversible harm to the beta-adrenergic system in the brain of lead-exposed rats, this study sets up an animal model to estimate the change in the sympathetic nervous system of brain after lead exposure was withdrawn. We address the following topics in this study: (a) the relationship between withdrawal time of lead exposure and brain beta-adrenergic receptor, blood lead level, and brain lead level in lead-exposed rats after lead exposure was stopped; and (b) the relationship between lead level and beta-adrenergic receptor and cyclic AMP (c-AMP) in brain. Wistar rats were chronically fed with 2% lead acetate and water for 2 months. Radioligand binding was assayed by a method that fulfilled strict criteria of beta-adrenergic receptor using the ligand [125I]iodocyanopindolol. The levels of lead were determined by electrothermal atomic absorption spectrometry. The c-AMP level was determined by radioimmunoassay. The results showed a close relationship between decreasing lead levels and increasing numbers of brain beta-adrenergic receptors and brain adenylate cyclase activity after lead exposure was withdrawn. The effect of lead exposure on the beta-adrenergic system of the brain is a partly reversible condition.


Assuntos
Adenilil Ciclases/metabolismo , Encéfalo/metabolismo , Intoxicação por Chumbo/metabolismo , Chumbo/toxicidade , Receptores Adrenérgicos beta/metabolismo , Antagonistas Adrenérgicos beta/farmacologia , Animais , Encéfalo/enzimologia , AMP Cíclico/metabolismo , Modelos Animais de Doenças , Iodocianopindolol/farmacologia , Chumbo/farmacocinética , Intoxicação por Chumbo/enzimologia , Masculino , Radioimunoensaio , Ratos , Ratos Wistar , Fatores de Tempo , Distribuição Tecidual
16.
Arch Dermatol Res ; 295(7): 293-6, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14615895

RESUMO

The importance of nitric oxide (NO) in mediating vasodilation, neurotransmission, and immune and inflammatory responses has been demonstrated. Human keratinocyte express inducible nitric oxide synthase (iNOS) and the neuronal constitutive isoform of NOS (ncNOS). We established an in vitro model in keratinocytes to investigate changes in NO, iNOS and ncNOS expression after UVB exposure. We demonstrated a large induction of NO after UVB exposure and that the source of NO produced in UVB-exposed keratinocytes was increased expression of iNOS and ncNOS. The increased NO production with increased expression of iNOS and ncNOS may contribute to the pathological and physiological features of UVB-induced erythema and skin inflammation.


Assuntos
Queratinócitos/enzimologia , Queratinócitos/efeitos da radiação , Óxido Nítrico Sintase/metabolismo , Raios Ultravioleta , Células Cultivadas , Relação Dose-Resposta à Radiação , Humanos , Queratinócitos/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo II
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