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1.
Rev Sci Instrum ; 92(1): 013507, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33514259

RESUMO

Optical emission spectroscopy is widely used in semiconductor and display manufacturing for plasma process monitoring. However, because of the contamination of the viewport, quantitative analysis is extremely difficult; therefore, qualitative analysis is used to detect species in the process. To extend plasma monitoring in advanced precise processes, the contamination problem of the viewport must be solved. We propose a new spectrum monitoring apparatus with a roll-to-roll transparent film window for optical diagnostics of a plasma system. By moving a transparent film in front of the viewport, contamination in the emission light path becomes negligible. However, the speed of the film should be optimized to reduce the maintenance period and to minimize measurement errors. We calculated the maximum thickness of SiO2, Si3N4, ITO, and the Ar/CHF3 plasma contaminant to suppress the electron temperature error measured by the line-intensity-ratio within 2% at 2 eV. The thickness of the Si3N4, ITO, and Ar/CHF3 plasma contaminant should be thinner than 12.5 nm, 7.5 nm, and 100 nm, respectively.

2.
Mol Cell Biochem ; 410(1-2): 247-54, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26359088

RESUMO

Obesity is a serious medical condition causing various diseases such as heart disease, type-2 diabetes, and cancer. Fat cells (adipocytes) play an important role in the generation of energy through hydrolysis of lipids they accumulate. Therefore, induction of lipolysis (breakdown of lipids into fatty acids and glycerol), is one of the ways to treat obesity. In the present study, we investigated the lipolytic effect of widdrol in 3T3-L1 adipocytes and its mechanism. Widdrol considerably increased the amount of glycerol released from 3T3-L1 adipocytes into the medium in a time- and dose-dependent manner. To determine the mechanism of this effect, we investigated the alterations in glycerol release and protein expression in 3T3-L1 adipocytes treated with widdrol alone or widdrol and inhibitors of proteins involved in the cAMP-dependent pathway or cAMP-independent PKC-MAPK pathway, which are known to induce lipolysis in adipocytes. The adenylyl cyclase inhibitor SQ-22536, PLA2 inhibitor dexamethasone, PI3K inhibitor wortmannin, and PKA inhibitor H-89, which were used to investigate the involvement of the cAMP-dependent pathway, did not affect the lipolytic effect of widdrol. Widdrol-induced phosphorylation of PKC, MEK, and ERK, which are related to the PKC-MAPK pathway, and their phosphorylation was inhibited by their inhibitors (H-7, U0126, and PD-98059, respectively). Moreover, the increase in glycerol release induced by widdrol was almost completely blocked by PKC, MEK, and ERK inhibitors. These results suggest that widdrol induces lipolysis through activation of the PKC-MEK-ERK pathway.


Assuntos
Adipócitos/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Benzocicloeptenos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Lipólise/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteína Quinase C/metabolismo , Células 3T3-L1 , Adipócitos/enzimologia , Animais , Relação Dose-Resposta a Droga , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Glicerol/metabolismo , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Fosforilação , Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
3.
Oncol Rep ; 34(3): 1178-84, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26133679

RESUMO

Widdrol is an odorous compound derived from Juniperus chinensis that is widely used in traditional medicine to treat fever, inflammation and cancer. It was previously reported that widdrol has antitumor activity by apoptosis induction in cancer cells in vitro. However, its anti-angiogenic activity remains elusive. In the present study, we investigated the anti­angiogenic activity of widdrol and the molecular mechanisms involved. Widdrol inhibited cell proliferation via G1 phase arrest induction in human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner. Additionally, it was associated with a decreased expression of cyclin-dependent kinase 2 (CDK2) and an increased expression of p21, a CDK inhibitor. Widdrol significantly inhibited the cell migration and tube formation of HUVECs using an in vitro angiogenesis assay. The results showed that widdrol suppressed phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2) and its downstream proteins, such as AKT, focal adhesion kinase (FAK) and endothelial nitric oxide synthase (eNOS). Moreover, widdrol effectively reduced tumor growth and blood vessel formation in colon tumor xenograft mice. Collectively, these results suggested that widdrol may act as a potential anti-angiogenic agent by inhibiting vessel sprouting and growth, which may have implications for angioprevention.


Assuntos
Inibidores da Angiogênese/farmacologia , Benzocicloeptenos/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Juniperus/química , Transdução de Sinais/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Western Blotting , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Patológica/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Med Chem ; 58(4): 2036-41, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-25658656

RESUMO

We performed a virtual screen of ∼340 000 small molecules against the active site of proteasomes followed by in vitro assays and subsequent optimization, yielding a proteasome inhibitor with pyrazole scaffold. The pyrazole-scaffold compound displayed excellent metabolic stability and was highly effective in suppressing solid tumor growth in vivo. Furthermore, the effectiveness of this compound was not negatively impacted by resistance to bortezomib or carfilzomib.


Assuntos
Antineoplásicos/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Neoplasias Experimentais/tratamento farmacológico , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/farmacologia , Pirazóis/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Domínio Catalítico/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Simulação por Computador , Relação Dose-Resposta a Droga , Humanos , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Moleculares , Estrutura Molecular , Neoplasias Experimentais/patologia , Inibidores de Proteassoma/administração & dosagem , Inibidores de Proteassoma/química , Pirazóis/administração & dosagem , Pirazóis/química , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
5.
Arch Pharm Res ; 37(6): 713-20, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24014306

RESUMO

Fucosterol is a sterol metabolite of brown algae and regulates genes involved with cholesterol homeostasis. As a part of our continuous search for anti-obesity agents from natural marine sources, the anti-adipogenic activities of Ecklonia stolonifera and its sterol, fucosterol, were evaluated for the inhibition of adipocyte differentiation and lipid formation. Oil Red O staining was used to evaluate triglyceride contents in 3T3-L1 pre-adipocytes primed by differentiation medium (DM) I and DM II. The methanolic extract of E. stolonifera showed strong anti-adipogenic activity, and was thus fractionated with several solvents. Among the tested fractions, the dichloromethane (CH2Cl2) fraction was found to be the most active fraction, with significant inhibition (40.5 %) of intracellular lipid accumulation at a non-toxic concentration, followed by the ethyl acetate fraction (30.2 %) at the same concentration, while the n-butanol and water fractions did not show inhibitory activity within the tested concentrations. The strong anti-adipogenic CH2Cl2-soluble fraction was further purified by a repeated chromatography to yield fucosterol. Fucosterol reduced lipid contents in a concentration-dependent manner without showing any cytotoxicity. Fucosterol treatment also yielded a decrease in the expression of the adipocyte marker proteins peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα) in a concentration-dependent manner. Taken together, these results suggest that fucosterol inhibits expression of PPARγ and C/EBPα, resulting in a decrease of lipid accumulation in 3T3-L1 pre-adipocytes, indicating that the potential use of E. stolonifera and its bioactive fucosterol as an anti-obesity agent.


Assuntos
Células 3T3-L1/efeitos dos fármacos , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Phaeophyceae , Estigmasterol/análogos & derivados , Células 3T3-L1/fisiologia , Adipócitos/fisiologia , Adipogenia/fisiologia , Animais , Fármacos Antiobesidade/química , Fármacos Antiobesidade/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Camundongos , Estigmasterol/química , Estigmasterol/isolamento & purificação , Estigmasterol/farmacologia
6.
Fitoterapia ; 92: 260-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24334103

RESUMO

The dramatic increase in obesity-related diseases emphasizes the need to elucidate the cellular and molecular mechanisms underlying fat metabolism. Inhibition of adipocyte differentiation has been suggested to be an important strategy for preventing or treating obesity. In our previous study, we characterized an Ecklonia stolonifera extract and non-polar fractions thereof, including dichloromethane and ethyl acetate fractions. We showed that these fractions inhibited adipocyte differentiation and lipid formation/accumulation in 3T3-L1 preadipocytes, as assessed by Oil Red O staining. As part of our ongoing search for anti-obesity agents derived from E. stolonifera, in this work, we characterized five known phlorotannins, including phloroglucinol, eckol, dieckol, dioxinodehydroeckol, and phlorofucofuroeckol A, all of which were isolated from the active ethyl acetate fraction of E. stolonifera. We determined the chemical structures of these phlorotannins through comparisons of published nuclear magnetic resonance (NMR) spectral data. Furthermore, we screened these phlorotannins for their abilities to inhibit adipogenesis over a range of concentrations (12.5-100 µM). Of these five phlorotannins, phloroglucinol, eckol, and phlorofucofuroeckol A significantly concentration-dependently inhibited lipid accumulation in 3T3-L1 cells without affecting cell viability. In addition, the five isolated phlorotannins also significantly reduced the expression levels of several adipocyte marker genes, including proliferator activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), although they did so to different extents. These results suggest that the molecular weight of a phlorotannin is an important factor affecting its ability to inhibit adipocyte differentiation and modulate the expression levels of adipocyte marker genes.


Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Obesidade/metabolismo , PPAR gama/metabolismo , Phaeophyceae/química , Taninos/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Fármacos Antiobesidade/química , Fármacos Antiobesidade/isolamento & purificação , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Dioxinas/química , Dioxinas/isolamento & purificação , Dioxinas/farmacologia , Dioxinas/uso terapêutico , Regulação para Baixo , Camundongos , Obesidade/genética , Obesidade/prevenção & controle , PPAR gama/genética , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Taninos/química , Taninos/isolamento & purificação , Taninos/uso terapêutico
7.
PLoS One ; 8(10): e75144, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24130685

RESUMO

Development of drug-resistant mutations has been a major problem with all currently developed Hepatitis C Virus (HCV) NS3/4A inhibitors, including the two FDA approved drugs, significantly reducing the efficacy of these inhibitors. The high incidence of drug-resistance mutations and the limited utility of these inhibitors against only genotype 1 highlight the need for novel, broad-spectrum HCV therapies. Here we used high-throughput screening (HTS) to identify low molecular weight inhibitors against NS3/4A from multiple genotypes. A total of 40,967 compounds from four structurally diverse molecular libraries were screened by HTS using fluorescence-based enzymatic assays, followed by an orthogonal binding analysis using surface plasmon resonance (SPR) to eliminate false positives. A novel small molecule compound was identified with an IC50 value of 2.2 µM against the NS3/4A from genotype 1b. Mode of inhibition analysis subsequently confirmed this compound to be a competitive inhibitor with respect to the substrate, indicating direct binding to the protease active site, rather than to the allosteric binding pocket that was discovered to be the binding site of a few recently discovered small molecule inhibitors. This newly discovered inhibitor also showed promising inhibitory activity against the NS3/4As from three other HCV genotypes, as well as five common drug-resistant mutants of genotype 1b NS3/4A. The inhibitor was selective for NS3 from multiple HCV genotypes over two human serine proteases, and a whole cell lysate assay confirmed inhibitory activity in the cellular environment. This compound provides a lead for further development of potentially broader spectrum inhibitors.


Assuntos
Antivirais/farmacologia , Hepacivirus/enzimologia , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Sequência de Aminoácidos , Avaliação Pré-Clínica de Medicamentos/métodos , Hepacivirus/efeitos dos fármacos , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos
8.
J Korean Soc Coloproctol ; 28(2): 111-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22606652

RESUMO

Primary ovarian lymphoma is a rare malignancy whose symptoms or signs are usually nonspecific. In this article, we report a very rare case initially presenting as a rectal submucosal-tumor-like lesion with a defecation disturbance caused by primary ovarian lymphoma with bilateral involvement. A 42-year-old woman visited chungnam national university hospital complaining of persistent defecation disturbance for 6 months. Colonoscopy demonstrated compression of the rectum by an extrinsic mass mimicking a rectal submucosal tumor. Magnetic resonance imaging detected bilateral ovarian tumors, 9.3 cm and 5.4 cm each in diameter, compressing the rectum without enlarged lymph nodes. The diagnosis was established following a bilateral adnexectomy and histological studies of the excised tissue. The tumor was classified as a diffuse large B-cell lymphoma. The patient was prescribed six cycles of standard CHOP (cyclophosphamide, hydroxydaunorubicin, vincristine, prednisolone) regimen and is presently on treatment.

9.
J Microbiol Biotechnol ; 22(6): 806-13, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22573158

RESUMO

Adipocyte differentiation is strongly associated with obesity, which causes metabolic disorders. In this study, we investigated the inhibitory effects of widdrol on 3T3- L1 preadipocyte growth and differentiation. Widdrol decreased lipid droplet accumulation and down-regulated adipogenic transcription factors such as C/EBPalpha, C/EBPbeta, and PPARgamma. Widdrol blocked preadipocyte proliferation and differentiation through the inhibition of mitotic clonal expansion, which was accompanied by the failure of degradation of p21, a cyclin-dependent kinase inhibitor. Cell-cycle analysis clearly indicated that widdrol actively induces cell-cycle arrest at the G1-S phage transition, causing cells to remain in the preadipocyte state. Moreover, widdrol increased p21 expression and inhibited Rb phosphorylation in preadipocyte incubated in a hormone medium. Therefore, these findings clearly suggest that widdrol blocks preadipocyte growth and differentiation through the inhibition of mitotic clonal expansion by p21- and Rb-dependent G1 arrest and can be developed as a potent anti-adipogenic agent for reducing obesity.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/fisiologia , Benzocicloeptenos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidores do Crescimento/metabolismo , Animais , Linhagem Celular , Camundongos , Mitose/efeitos dos fármacos
10.
Br J Clin Pharmacol ; 69(2): 160-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20233179

RESUMO

AIMS: The aim of the study was to determine the effects of oral clotrimazole troches on the pharmacokinetics of oral and intravenous midazolam in the plasma. METHODS: We conducted a randomized, open-label, four-way crossover study in 10 healthy volunteers. Each volunteer received oral midazolam 2 mg or intravenous midazolam 0.025 mg kg(-1) with and without oral clotrimazole troches 10 mg taken three times daily for 5 days. Each study period was separated by 14 days. Serial blood samples were collected up to 24 h after oral midazolam and 6 h after intravenous midazolam. Plasma concentrations for midazolam and its metabolite 1-hydroxymidazolam were measured and fitted to a noncompartmental model to estimate the pharmacokinetic parameters. RESULTS: Ten healthy volunteers aged 21-26 years provided written informed consent and were enrolled into the study. Clotrimazole decreased the apparent oral clearance of midazolam from 57 +/- 13 l h(-1)[95% confidence interval 48, 66] to 36 +/- 9.8 l h(-1) (95% confidence interval 29, 43) (P= 0.003). These changes were accompanied by a decrease in the area under the concentration-time curve (mean difference 22 microg h(-1) l(-1), P= 0.001) and bioavailability (mean difference 0.21, P= NS). There were no significant differences in the systemic clearance of midazolam with or without clotrimazole troches. CONCLUSIONS: Oral clotrimazole troches decreased the apparent oral clearance of midazolam; no significant differences in the systemic clearance of midazolam were found.


Assuntos
Ansiolíticos/farmacocinética , Antifúngicos/farmacocinética , Clotrimazol/farmacologia , Citocromo P-450 CYP3A/metabolismo , Midazolam/farmacocinética , Administração Oral , Adolescente , Adulto , Análise de Variância , Ansiolíticos/administração & dosagem , Antifúngicos/administração & dosagem , Área Sob a Curva , Clotrimazol/administração & dosagem , Estudos Cross-Over , Interações Medicamentosas , Feminino , Humanos , Injeções Intravenosas , Masculino , Taxa de Depuração Metabólica , Midazolam/administração & dosagem , Pessoa de Meia-Idade
11.
Eur J Clin Pharmacol ; 65(7): 651-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19357842

RESUMO

PURPOSE: We conducted a prospective, open-label study in 54 adult subjects with sickle cell disease to determine the relationship between morphine concentrations, cytochrome P450 (CYP) 2D6 genotype, and clinical outcomes. METHODS: A blood sample was obtained for genotyping and serial blood samples were drawn to measure codeine and its metabolites in the plasma before and after oral codeine sulfate 30 mg. Codeine and its metabolites were measured by liquid chromatography-tandem mass spectrometry (LC-MS). CYP2D6 genetic testing included four single nucleotide polymorphisms (SNP) indicative of three variant alleles: *17 (1023T); *29 (1659A, 3183A); and *41 (2988A) alleles. RESULTS: Thirty subjects (group I) had a mean (standard deviation) maximal morphine concentration of 2.0 (1.0) ng/ml. Morphine was not measurable in the remaining 24 subjects (group II). Nine (30%) subjects in group I and 11 (46%) subjects in group II carried a variant *17, *29, or *41 allele (p = 0.23); one (3%) subject in group I and 5 (21%) subjects in group II were homozygous for *17 or *29 allele (p = 0.07). Emergency room visits (group I 1.5 +/- 1.8 vs. group II 2.1 +/- 4.3, p = NS) did not differ based on metabolic status, but more hospital admissions (0.9 +/- 1.4 vs. 2.2 +/- 4.1, p = 0.05) were documented in patients with no measurable morphine concentrations. CONCLUSIONS: We conclude that Blacks with sickle cell disease without measurable plasma morphine levels after a single dose of codeine were not more likely to be a carrier of a single variant allele commonly associated with reduced CYP2D6 metabolic capacity; however, homozygosity for a variant CYP2D6 allele may result in reduced metabolic capacity. Furthermore, it appears that subjects without measurable morphine concentrations were more likely to be admitted to the hospital for an acute pain crisis.


Assuntos
Analgésicos Opioides/farmacocinética , Anemia Falciforme/genética , População Negra/estatística & dados numéricos , Codeína/farmacocinética , Morfina/farmacocinética , Adulto , Alelos , Analgésicos Opioides/química , Analgésicos Opioides/metabolismo , Área Sob a Curva , Codeína/química , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Feminino , Genótipo , Meia-Vida , Heterozigoto , Homozigoto , Humanos , Masculino , Taxa de Depuração Metabólica , Estrutura Molecular , Morfina/química , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Valores de Referência
13.
Cancer Lett ; 184(1): 117-21, 2002 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-12104055

RESUMO

The clinical significance of osteonectin in human stomach cancer was examined immunohistochemically and molecular biologically in 31 differentiated and eight undifferentiated stomach adenocarcinomas and 19 non-cancer stomach tissues. Osteonectin-mAb-stained cells were observed in stroma of 90% differentiated and 63% undifferentiated adenocarcinomas, and of 26% non-cancer stomach tissues. Competitive reverse transcriptase polymerase chain reaction results generally coincided with immunohistochemical data. The present results suggest that osteonectin is highly expressed in reactive stroma associated with invasive differentiated adenocarcinomas and that it may serve as a useful clinical diagnostic marker for stomach cancer.


Assuntos
Adenocarcinoma/metabolismo , Osteonectina/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Primers do DNA/química , Humanos , Técnicas Imunoenzimáticas , Osteonectina/genética , RNA Neoplásico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia
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