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1.
Sci Adv ; 8(11): eabk1538, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35302851

RESUMO

RAF kinases are highly conserved serine/threonine kinases, and among the three RAF isoforms (ARAF, BRAF, and CRAF), the pathophysiological relevance of ARAF is not well defined. Here, we show that patients with lung cancer exhibit low expression of ARAF, which is associated with lymph node metastasis and poor patient survival. We uncover that depletion of ARAF promotes anchorage-independent growth and metastasis through activation of AKT signaling in a subset of lung cancer cells. We identified that loss of ARAF was associated with an increase in ERBB3 expression in a kinase-independent manner. ARAF suppressed the promoter activity of ERBB3, and reconstitution of ARAF in ARAF-depleted cells led to the reversal of enhanced ERBB3-AKT signaling. Furthermore, ARAF inhibited neuregulin 1 (hNRG1)-mediated AKT activation through controlling ERBB3 expression via the transcription factor KLF5. Our results disclose a critical dual role for ARAF kinase in the negative regulation of ERBB3-AKT signaling, thereby suppressing tumor metastasis.


Assuntos
Neoplasias Pulmonares , Quinases raf , Humanos , Neoplasias Pulmonares/genética , Proteínas Serina-Treonina Quinases , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismo , Transdução de Sinais , Quinases raf/metabolismo
2.
J Immunol Res ; 2020: 4832189, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32724828

RESUMO

Nasal polyposis often is characterized by a persistent inflammation of the sinonasal mucosa, disease recurrence after medical or surgical intervention, and asthma comorbidity. Dysregulated complement activation may contribute to immunologic alterations and disease. To date, there is only scattered knowledge on the source and regulation of the central complement factors in the pathogenesis of nasal polyps. Here, we aim to study complement signatures, especially the C3-C3aR axis, and focus on cellular sources and targets in nasal polyps. Expression of complement factors, including C3, C5, and the anaphylatoxin receptors, was analyzed in nasal polyp tissue samples, the corresponding inferior turbinates, and healthy controls using transcriptomic methods and protein measurements. Distinct patterns of complement expression were found in nasal polyps compared to controls, characterized by an increased C3 activation and an increase in C3aR-bearing cells. In contrast, no difference was shown for epithelial-dependent C3 production. Besides low intracellular C3-expression levels for lymphocytes in general, we could identify an enlarged B lymphocyte population in nasal polyps displaying high amounts of intracellular C3. Our data suggest a prominent role for the C3-C3aR-axis in nasal polyps and, for the first time, describe a B cell population containing high levels of intracellular C3, suggesting a new role of B cells in the maintenance of the inflammation by complement.


Assuntos
Linfócitos B/imunologia , Complemento C3/imunologia , Pólipos Nasais/imunologia , Feminino , Humanos , Inflamação/imunologia , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/imunologia , Receptores Acoplados a Proteínas G/imunologia , Transcriptoma/imunologia
3.
Front Pharmacol ; 10: 1160, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31680951

RESUMO

The mycotoxin zearalenone (ZEN) is produced by many plant pathogenic Fusarium species. It is well known for its estrogenic activity in humans and animals, but whether ZEN has a role in plant-pathogen interaction and which process it is targeting in planta was so far unclear. We found that treatment of Arabidopsis thaliana seedlings with ZEN induced transcription of the AtHSP90.1 gene. This heat shock protein (HSP) plays an important role in plant-pathogen interaction, assisting in stability and functionality of various disease resistance gene products. Inhibition of HSP90 ATPase activity impairs functionality. Because HSP90 inhibitors are known to induce HSP90 gene expression and due to the structural similarity with the known HSP90 inhibitor radicicol (RAD), we tested whether ZEN and its phase I metabolites α- and ß-zearalenol are also HSP90 ATPase inhibitors. Indeed, AtHSP90.1 and wheat TaHSP90-2 were inhibited by ZEN and ß-zearalenol, while α-zearalenol was almost inactive. Plants can efficiently glycosylate ZEN and α/ß-zearalenol. We therefore tested whether glucosylation has an effect on the inhibitory activity of these metabolites. Expression of the A. thaliana glucosyltransferase UGT73C6 conferred RAD resistance to a sensitive yeast strain. Glucosylation of RAD, ZEN, and α/ß-zearalenol abolished the in vitro inhibitory activity with recombinant HSP90 purified from Escherichia coli. In conclusion, the mycotoxin ZEN has a very prominent target in plants, HSP90, but it can be inactivated by glycosylation. This may explain why there is little evidence for a virulence function of ZEN in host plants.

4.
Front Genet ; 10: 856, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31608108

RESUMO

Library preparation for whole-exome sequencing is a critical step serving the enrichment of the regions of interest. For Ion Proton, there are only two exome library preparation methods available, AmpliSeq and SureSelect. Although of major interest, a comparison of the two methods is hitherto missing in the literature. Here, we systematically evaluate the performance of AmpliSeq and SureSelect and present an improved variant calling pipeline. We used 12 in-house DNA samples with genome-wide and exome microarray data and a commercially available reference DNA (NA12878) for evaluation. Both methods had a high concordance (>97%) with microarray genotypes and, when validating against NA12878, a sensitivity and positive predictive values of >93% and >80%, respectively. Application of our variant calling pipeline decreased the number of false positive variants dramatically by 90% and resulted in positive predictive value of 97%. This improvement is highly relevant in research as well as clinical setting.

5.
Endocr Pathol ; 29(3): 294-298, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29766416

RESUMO

A 67-year-old man was adrenalectomized due to a tumor measuring 100 mm. Specimens revealed an inflammation with slight fibrosis and moderate infiltrates of lymphocytes and plasmacytes with immunoreactivity for IgG and IgG4 resulting in the diagnosis of an active IgG4-associated adrenalitis. To our knowledge, this is the first reported active adrenalitis of this type. It should be the precursor lesion of the adrenal calcifying fibrous tumor that was reported once before.


Assuntos
Doenças das Glândulas Suprarrenais/patologia , Granuloma de Células Plasmáticas/patologia , Doença Relacionada a Imunoglobulina G4/patologia , Idoso , Humanos , Imunoglobulina G , Masculino
6.
Mov Disord ; 31(4): 555-62, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26879346

RESUMO

BACKGROUND: In a small group of patients, we have previously shown that a combination of electrophysiological tests was able to distinguish functional (psychogenic) tremor and organic tremor with excellent sensitivity and specificity. OBJECTIVES: This study aims to validate an electrophysiological test battery as a tool to diagnose patients with functional tremor with a "laboratory-supported" level of certainty. METHODS: For this prospective data collection study, we recruited 38 new patients with functional tremor (mean age 37.9 ± 24.5 years; mean disease duration 5.9 ± 9.0 years) and 73 new patients with organic tremor (mean age 55.4 ± 25.4 years; mean disease duration 15.8 ± 17.7 years). Tremor was recorded at rest, posture (with and without loading), action, while performing tapping tasks (1, 3, and 5 Hz), and while performing ballistic movements with the less-affected hand. Electrophysiological tests were performed by raters blinded to the clinical diagnosis. We calculated a sum score for all performed tests (maximum of 10 points) and used a previously suggested cut-off score of 3 points for a diagnosis of laboratory-supported functional tremor. RESULTS: We demonstrated good interrater reliability and test-retest reliability. Patients with functional tremor had a higher average score on the test battery when compared with patients with organic tremor (3.6 ± 1.4 points vs 1.0 ± 0.8 points; P < .001), and the predefined cut-off score for laboratory-supported functional tremor yielded a test sensitivity of 89.5% and a specificity of 95.9%. CONCLUSION: We now propose this test battery as the basis of laboratory-supported criteria for the diagnosis of functional tremor, and we encourage its use in clinical and research practice.


Assuntos
Acelerometria/métodos , Eletromiografia/métodos , Exame Neurológico/métodos , Transtornos Psicofisiológicos/diagnóstico , Tremor/diagnóstico , Acelerometria/normas , Adulto , Idoso , Eletromiografia/normas , Medicina Baseada em Evidências , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico/normas , Transtornos Psicofisiológicos/fisiopatologia , Reprodutibilidade dos Testes , Método Simples-Cego , Tremor/fisiopatologia
7.
Parkinsonism Relat Disord ; 20(3): 323-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24345964

RESUMO

BACKGROUND: Previous case series suggested a link between Klinefelter syndrome (KS) and essential tremor (ET) or an ET-like syndrome. METHODS: We investigated three KS-patients with tremor including tremor-analyzes and discuss our data in context to findings from a literature review. The clinical outcome after deep brain stimulation (DBS) is also reviewed. RESULTS: Tremor in KS is predominantly a postural and kinetic tremor that resembles ET. Our patients were further characterized by absent family history for tremor in first degree relatives, lack of subjective alcohol responsiveness inquired by history, and tremor onset in childhood. One of our patients and two cases from literature improved after DBS of the ventral intermediate nucleus (VIM) of the thalamus. CONCLUSIONS: Tremor in KS shares several features with ET. If other characteristics such as family history, alcohol responsiveness, and age at tremor onset may serve as discriminating factors from ET, needs to be further investigated. First observations suggest that VIM-DBS may be efficacious.


Assuntos
Síndrome de Klinefelter/complicações , Síndrome de Klinefelter/diagnóstico , Tremor/complicações , Tremor/diagnóstico , Adulto , Humanos , Síndrome de Klinefelter/genética , Masculino , Pessoa de Meia-Idade , Tremor/genética , Adulto Jovem
8.
J Clin Pharmacol ; 50(2): 160-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19934028

RESUMO

Signals from pharmacovigilance studies indicate that women are at higher risk for adverse drug reactions (ADRs) due to diuretics. Despite the long-term use of torasemide, there are few studies investigating gender differences of torasemide pharmacokinetics in the hospital setting. Therefore, torasemide pharmacokinetics were investigated in 90 patients (45 women, 45 men) during steady-state conditions. Torasemide elimination was significantly reduced in women compared with men (eg, body-weight-normalized area under the concentration-time curve: 42.1 +/- 20.4 vs 30.9 +/- 10.3 kg.h/L; P < .001). Among the investigated genetic factors [SLC22A11(OAT4), SLCO1B1(OATP1B1), CYP2C9], only the SLCO1B1c.521T>C polymorphism had a significant influence on torasemide pharmacokinetics. Using cell lines expressing OATP1B1, the authors identified torasemide as OATP1B1 substrate (K(m) = 6.2 microM) with a significant reduction of uptake by the 521C-variant. Taken together, gender differences in torasemide pharmacokinetics are likely to contribute to a higher rate of ADRs in women, which has, for example, been observed in a German Pharmacovigilance Project with 66% of hospitalizations due to torasemide ADRs occurring in women.


Assuntos
Diuréticos/farmacocinética , Transportadores de Ânions Orgânicos/genética , Sulfonamidas/farmacocinética , Linhagem Celular , Diuréticos/administração & dosagem , Diuréticos/efeitos adversos , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Hipertensão/tratamento farmacológico , Transportador 1 de Ânion Orgânico Específico do Fígado , Masculino , Mutagênese Sítio-Dirigida , Transportadores de Ânions Orgânicos/metabolismo , Polimorfismo Genético , Fatores Sexuais , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Torasemida
9.
Planta Med ; 74(14): 1701-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18975255

RESUMO

Products derived from roots of Leuzea carthamoides (Maral root) are being promoted as dietary supplements with anti-aging, adaptogenic and anabolic activity, without much scientific evidence. We investigated the effects of a lipophilic Leuzea root extract and the major phytoecdysteroid, 20-hydroxyecdysone, in human breast adenocarcinoma MCF-7 cells. Cell proliferation was inhibited by the extract (IC50 = 30 microg/mL) but not by 20-hydroxyecdysone. Genome-wide expression profiling using Affymetrix HG U133 Plus 2.0 microarrays was carried out to analyse effects at the transcriptional level. 241 genes appeared to be differentially expressed after Leuzea treatment, more than after treatment with either 17beta-estradiol or tamoxifen. Transcripts linked to cell cycle regulation and DNA replication were highly over-represented and regulated in an anti-proliferative manner. Genes involved in apoptosis were regulated in a pro-apoptotic manner. Expression levels of several oxidoreductase transcripts were strongly induced, most prominent CYP1A1, known to be regulated via the aryl hydrocarbon receptor pathway. An XRE-dependent reporter gene assay confirmed the AhR-agonistic activity of the Leuzea root extract, whereas 20-hydroxyecdysone was not active. Leuzea extract also inhibited 5alpha-reductase, type II. While the extract significantly modulates cellular activities, the phytoecdysteroids, are most likely not the active principles of L. carthamoides.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias da Mama/metabolismo , Leuzea/química , Extratos Vegetais/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genoma , Humanos , Extratos Vegetais/química , Raízes de Plantas/química
10.
Clin Pharmacokinet ; 47(5): 323-32, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18399713

RESUMO

BACKGROUND: Torasemide is frequently used for the treatment of hypertension and heart failure. However, the determinants of torasemide pharmacokinetics in patients during steady-state conditions are largely unknown. We therefore explored the impact of genetic polymorphisms of cytochrome P450 (CYP) 2C9 (CYP2C9) and organic anion transporting polypeptide (OATP) 1B1 (SLCO1B1), gender, and the effects of losartan and irbesartan comedication on the interindividual variability of steady-state pharmacokinetics of torasemide. PATIENTS AND METHODS: Twenty-four patients receiving stable medication with torasemide 10 mg once daily and with an indication for additional angiotensin II receptor blocker (ARB) treatment to control hypertension or to treat heart failure were selected. Blood samples were taken before torasemide administration and 0.5, 1, 2, 4, 8, 12 and 24 hours after administration. After this first study period, patients received either irbesartan 150 mg (five female and seven male patients aged 69+/-8 years) or losartan 100 mg (two female and ten male patients aged 61+/-8 years) once daily. After 3 days of ARB medication, eight blood samples were again collected at the timepoints indicated above. The patients' long-term medications, which did not include known CYP2C9 inhibitors, were maintained at a constant dose during the study. All patients were genotyped for CYP2C9 (*1/*1 [n=15]; *1/*2 [n = 4]; *1/*3 [n=5]) as well as for SLCO1B1 (c.521TT [n=13]; c.521TC [n=11]). RESULTS: Factorial ANOVA revealed an independent impact of the CYP2C9 genotype (dose-normalized area under the plasma concentration-time curve during the 24-hour dosing interval at steady state [AUC(24,ss)/D]: *1/*1 375.5+/-151.4 microg x h/L/mg vs *1/*3 548.5+/-271.6 microg x h/L/mg, p=0.001), the SLCO1B1 genotype (AUC(24,ss)/D: TT 352.3+/-114 microg x h/L/mg vs TC 487.6+/-218.4 microg x h/L/mg, p<0.05) and gender (AUC(24,ss)/D: males 359.5+/-72.2 microg x h/L/mg vs females 547.3+/-284 microg x h/L/mg, p<0.01) on disposition of torasemide. Coadministration of irbesartan caused a 13% increase in the AUC(24,ss)/D of torasemide (p=0.002), whereas losartan had no effect. CONCLUSION: This study shows that the CYP2C9*3 and SLCO1B1 c.521TC genotype and female gender are significant and independent predictors of the pharmacokinetics of torasemide. Coadministration of irbesartan yields moderate but significant increases in the torasemide plasma concentration and elimination half-life.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/efeitos adversos , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacocinética , Anti-Hipertensivos/farmacocinética , Sulfonamidas/farmacocinética , Idoso , Análise de Variância , Área Sob a Curva , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Calibragem , Cromatografia Líquida de Alta Pressão , Citocromo P-450 CYP2C9 , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Genótipo , Meia-Vida , Humanos , Transportador 1 de Ânion Orgânico Específico do Fígado , Masculino , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo , Farmacogenética , Caracteres Sexuais , Torasemida
11.
Angiology ; 58(2): 185-90, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17495267

RESUMO

Enhanced external counterpulsation (EECP) is a noninvasive counterpulsation technique that reduces angina and improves exercise capacity in patients with coronary artery disease. Diastolic coronary perfusion is augmented by pneumatic compression of 3 sets of cuffs wrapped around the lower extremities. Although central hemodynamic changes are well investigated, almost no data exist about the changes of peripheral circulation during EECP. In this study, 12 patients with angina and angiographic evidence of coronary artery disease were treated for 1 hour with EECP. In these patients, peripheral artery disease was excluded by duplex sonography. The patients rested 1 hour before EECP in supine position, and they remained in that position for 1 hour after the procedure. Changes of flow volumes and flow pattern of the posterior tibial artery and the brachial artery were measured by sonography at the end of all 3 periods. Furthermore, we measured the concentration of circulating prostanoids at these 3 time points. Averaged flow volume of the posterior tibial artery decreased to 69% +/- 23% (P < .05) during EECP and increased to 133% +/- 34% (P < .05) of baseline 1 hour after the procedure. In contrast, the averaged flow volume of the brachial artery increased by 9% +/- 4% (P < .05) during EECP and returned to baseline values after EECP. The flow pattern of the posterior tibial artery showed a second early diastolic antegrade flow caused by the cuff inflation and a reverse end-diastolic flow after the deflation of the cuffs. These flow changes caused an increase of the pulsatility index by Gosling (397% during EECP), returning to baseline values in the recovery period. Plasma concentrations of circulating prostanoids showed no significant change during EECP. Thus, pedal flow volume decreased to approximately two thirds of baseline during EECP followed by reactive hyperemia even 1 hour after the procedure; however, this decreased perfusion triggered no change of the prostacyclin/thromboxane ratio and was well tolerated by all investigated patients. The observed 4-fold increase of the peripheral pulsatility index supports the thesis of increase of shear-stress-related improvement of endothelial function during EECP.


Assuntos
Angina Pectoris/terapia , Doença da Artéria Coronariana/terapia , Contrapulsação/métodos , Perna (Membro)/irrigação sanguínea , Angina Pectoris/diagnóstico por imagem , Angina Pectoris/fisiopatologia , Velocidade do Fluxo Sanguíneo , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Perna (Membro)/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Decúbito Dorsal , Ultrassonografia Doppler Dupla
12.
J Clin Pharmacol ; 47(6): 715-26, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17442681

RESUMO

The aim of this study was to determine the analgesic effect of acetaminophen compared to a combination of both caffeine and acetaminophen or caffeine alone using tonic and phasic pain stimulation. Twenty-four subjects were treated orally with 1000 mg acetaminophen, 130 mg caffeine, and a combination of both in a 4-way crossover, double-blind, placebo-controlled study. Pharmacokinetics and analgesic effects were assessed by means of an experimental pain model based on pain-related cortical potentials after phasic stimulation of the nasal mucosa with CO(2) and based on pain ratings after tonic stimulation with dry air. Analgesic effects of acetaminophen and acetaminophen plus caffeine but not caffeine alone caused a significant reduction of pain-related cortical potentials beginning 30 minutes after medication. The combination demonstrated an enhanced effect throughout the observation time up to 3 hours. Caffeine accelerated acetaminophen absorption, indicated by enhanced early AUCs. Significant analgesic effects of the combination on tonic pain ratings were found throughout the observation time as compared to acetaminophen and placebo. In this study, caffeine enhanced and prolonged the analgesic activity of acetaminophen.


Assuntos
Acetaminofen/farmacocinética , Acetaminofen/uso terapêutico , Analgésicos não Narcóticos/farmacocinética , Analgésicos não Narcóticos/uso terapêutico , Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Dor/tratamento farmacológico , Adolescente , Adulto , Área Sob a Curva , Estudos Cross-Over , Método Duplo-Cego , Sinergismo Farmacológico , Feminino , Humanos , Absorção Intestinal , Masculino , Pessoa de Meia-Idade , Solubilidade
14.
Fundam Clin Pharmacol ; 20(3): 273-82, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16671962

RESUMO

Transporter proteins such as P-glycoprotein are major determinants of intracellular drug concentrations. Moreover, inhibition or induction of transporters is an important mechanism underlying drug interactions in humans. However, very little is known whether beta-adrenoceptor antagonists are substrates and/or inhibitors of P-glycoprotein. Therefore, we investigated the P-glycoprotein-mediated transport of propranolol, metoprolol, bisoprolol, carvedilol and sotalol in P-glycoprotein-expressing Caco-2 monolayers and inhibition of P-glycoprotein-mediated digoxin transport by the beta-adrenoceptor antagonists. A significant inhibition of polarized, basal to apical drug transport by the P-glycoprotein inhibitor PSC-833 was observed for bisoprolol (0.5 and 5 microm) and carvedilol (0.5 microm). Moreover, propranolol and carvedilol inhibited P-glycoprotein-mediated digoxin transport with IC(50) values of 24.8 and 0.16 microm, respectively, whereas metoprolol and sotalol had no effect. Bisoprolol significantly inhibited directional digoxin transport at 50 and 250 microm by 31% and 44%, respectively. Taken together, P-glycoprotein is likely to be one determinant of bisoprolol and carvedilol disposition in humans. In addition, the beta-adrenoceptor antagonists propranolol and carvedilol significantly inhibit P-glycoprotein function thereby possibly contributing to drug interactions in humans (e.g. digoxin-carvedilol and cyclosporine-carvedilol).


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antagonistas Adrenérgicos beta/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antagonistas Adrenérgicos beta/metabolismo , Bisoprolol/metabolismo , Bisoprolol/farmacologia , Células CACO-2 , Carbazóis/metabolismo , Carbazóis/farmacologia , Carvedilol , Ciclosporinas/farmacologia , Digoxina/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Humanos , Propanolaminas/metabolismo , Propanolaminas/farmacologia , Propranolol/metabolismo , Propranolol/farmacologia , Fatores de Tempo
15.
Am J Cardiol ; 95(12): 1531-2, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15950593

RESUMO

During an investigation of the possible pharmacokinetic interactions of cyclooxygenase-2 (COX-2) inhibitors with metoprolol, we observed that rofecoxib caused a significant reduction in heart rate in young healthy volunteers. The effect of valdecoxib did not reach significance. When these drugs were given together with metoprolol, the effect was continued. The latter effect could not be related to pharmacokinetic interactions. In the light of experimental results claiming a cardioprotective effect of possibly COX-2-derived prostaglandins and clinical observations hinting at an increased risk of sudden cardiovascular death in conjunction with the long-term use of selective cyclooxygenase inhibitors, our results may help to increase awareness and to suggest investigation of the impact of coxibs on heart function.


Assuntos
Inibidores de Ciclo-Oxigenase/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Antagonistas Adrenérgicos beta/farmacologia , Combinação de Medicamentos , Interações Medicamentosas , Eletrocardiografia Ambulatorial , Coração/efeitos dos fármacos , Coração/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Isoxazóis/farmacologia , Masculino , Metoprolol/farmacologia , Pirimidinas/farmacologia , Valores de Referência , Sulfadimetoxina/farmacologia , Sulfonamidas/farmacologia
16.
Biomed Chromatogr ; 19(2): 113-8, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15473012

RESUMO

A practicable and selective liquid chromatography-mass spectrometry assay for the determination of two cyclooxygenase-2 inhibitors, etoricoxib and valdecoxib, in human plasma is presented. The analytical technique is based on reversed-phase high-performance liquid chromatography (HPLC) coupled to atmospheric pressure chemical ionisation (APCI) mass spectrometry (Finnigan Mat LCQ ion trap). Mass analysis was performed in the positive ion mode. The ion trap was operated in the tandem MS mode (MS2) and the transitions of etoricoxib (m/z 359.2 --> 280.3) and valdecoxib (m/z 315.1 --> 235.1) were followed by selected reaction monitoring. Retention times of etoricoxib and valdecoxib were 1.05 and 1.08 min, respectively. The method was validated over a linear range 10-2500 and 5-1000 microg/L using the other substrate as internal standard. After validation, the method was used to study the pharmacokinetic pro fi le of etoricoxib or valdecoxib in a healthy volunteer after administration of a single oral dose (valdecoxib, 20 mg; etoricoxib, 90 mg). The presented method was suf fi cient to cover more than 90% of the area under the plasma concentration time curve.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Inibidores de Ciclo-Oxigenase/sangue , Isoxazóis/sangue , Espectrometria de Massas/métodos , Piridinas/sangue , Sulfonamidas/sangue , Sulfonas/sangue , Etoricoxib , Humanos , Isoxazóis/administração & dosagem , Isoxazóis/farmacocinética , Masculino , Piridinas/administração & dosagem , Piridinas/farmacocinética , Sensibilidade e Especificidade , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacocinética , Sulfonas/administração & dosagem , Sulfonas/farmacocinética
17.
Br J Clin Pharmacol ; 59(1): 80-4, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15606444

RESUMO

AIM: Diclofenac-K has been recently launched at low oral doses in different countries for over-the-counter use. However, given the considerable first-pass metabolism of diclofenac, the degree of absorption of diclofenac-K at low doses remained to be determined. The aim of this study was to determine the bioavailability of low-dose diclofenac-K. METHODS: A randomized, three-way, cross-over study was performed in 10 subjects. Each received diclofenac-K, 22.5 mg via short-term i.v. infusion and orally at single doses of 12.5 mg and 25 mg. RESULTS: Mean (+/- SD) times to maximal plasma concentration (t(max)) of diclofenac were 0.48 +/- 0.28 h (12.5 mg) and 0.93 +/- 0.96 h (25 mg). The absolute bioavailability of diclofenac-K after oral administration did not differ significantly in the 12.5-mg and 25-mg dose group (63.1 +/- 12.6%vs. 65.1 +/- 19.4%, respectively). The 90% confidence intervals for the AUC(infinity) and AUC(t) ratios for the two oral regimes were 82.6, 103.4% (point estimate 92.4%) and 86.2, 112.9% (point estimate 98.6%), respectively. These values were within the acceptance criteria for bioequivalence (80-125%). CONCLUSIONS: Our data indicate that diclofenac-K is rapidly and well absorbed at low dose, and are consistent with a rapid onset of action of the drug. Abbreviations AUC, area under plasma concentration-time curve; C(max), peak plasma concentration; CI, confidence interval; COX, cyclooxygenase; D, dose; F, absolute bioavailability; t(max), time to reach C(max).


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Inibidores de Ciclo-Oxigenase/farmacocinética , Diclofenaco/farmacocinética , Adulto , Anti-Inflamatórios não Esteroides/administração & dosagem , Área Sob a Curva , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Inibidores de Ciclo-Oxigenase/administração & dosagem , Diclofenaco/administração & dosagem , Feminino , Humanos , Masculino
18.
Am J Cardiol ; 94(10): 1319-21, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15541258

RESUMO

On average, metoprolol plasma concentration is doubled after an amiodarone loading dose (1.2 g/day over a period of 6 days). However, the individual amount of this drug interaction depends on the CYP2D6 genotype.


Assuntos
Amiodarona/farmacologia , Antiarrítmicos/farmacologia , Fibrilação Atrial/tratamento farmacológico , Metoprolol/farmacocinética , Idoso , Alelos , Antiarrítmicos/farmacocinética , Fibrilação Atrial/sangue , Fibrilação Atrial/genética , Citocromo P-450 CYP2D6/genética , Interações Medicamentosas , Quimioterapia Combinada , Feminino , Genótipo , Humanos , Masculino
19.
J Glaucoma ; 13(2): 158-62, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15097263

RESUMO

PURPOSE: Several studies indicate that calcium channel blockers improve the clinical course of normal tension glaucoma (NTG), whereas the underlying mechanism is not fully investigated. Hemodynamic improvement and neuroprotective effects are discussed. In this study, we measured the hemodynamic effects of nimodipine on retinal circulation. PATIENTS AND METHODS: Sixteen patients with NTG and clinical signs of vasospastic hyperreactivity, such as suffering from extremely cold hands and feet, were consecutively selected out of the local glaucoma registry. Ten healthy age-matched volunteers were included as controls. Retinal capillary blood flow was measured by Scanning Laser Doppler Flowmetry in both eyes before and 90 +/- 10 minutes after a single oral dose of 30 mg nimodipine. RESULTS: Before administration of nimodipine, retinal capillary blood flow was significantly reduced in NTG patients compared with controls (262 +/- 80 vs. 487 +/- 164 AU, P < 0.001). Nimodipine increased retinal capillary blood flow in NTG patients by 91 +/- 73% (P < 0.001) to values of healthy controls (440 +/- 113 vs. 439 +/- 123 AU, P = 0.635). In controls, nimodipine did not show significant effects. CONCLUSIONS: In NTG patients with additional vasospastic symptoms, retinal capillary blood is significantly reduced in comparison with healthy controls. Single-dose nimodipine yields to a normalization of retinal circulation in NTG patients up to values of healthy controls 90 minutes after drug administration.


Assuntos
Bloqueadores dos Canais de Cálcio/administração & dosagem , Glaucoma de Ângulo Aberto/tratamento farmacológico , Nimodipina/administração & dosagem , Doenças Retinianas/tratamento farmacológico , Vasos Retinianos/efeitos dos fármacos , Circulação Sanguínea , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Feminino , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pressão Intraocular/efeitos dos fármacos , Fluxometria por Laser-Doppler , Masculino , Pessoa de Meia-Idade , Disco Óptico/irrigação sanguínea , Fluxo Sanguíneo Regional/efeitos dos fármacos , Doenças Retinianas/fisiopatologia , Vasos Retinianos/fisiopatologia , Vasodilatação/efeitos dos fármacos
20.
Clin Cancer Res ; 9(12): 4324-31, 2003 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-14555502

RESUMO

PURPOSE: We investigated whether a short treatment with the cyclooxygenase-2 (COX-2) inhibitor celecoxib could modulate Ki67 antigen and the caspase cleavage product of keratin 18, recognized as a marker of early apoptosis. The activity of celecoxib on microvessel density (MVD) and angio-power Doppler sonography-derived indices of tumor vascularization was also assessed. Serum levels of squamous cell carcinoma antigen and the proliferative potential and subsets of peripheral T cells before and after celecoxib treatment were also analyzed. EXPERIMENTAL DESIGN: Tumor biopsy specimens from 14 patients with cervical cancer were obtained at baseline and after 10 days of celecoxib treatment (400 mg twice daily). Tumor and stroma COX-2 expression, Ki67, apoptosis, and MVD were assessed by immunohistochemistry, whereas prostaglandin E(2) levels were measured by RIA. RESULTS: At baseline, COX-2 integrated density values in tumor compartment ranged from 10.7 to 60.1 (median, 26.5) and were significantly higher than tumor COX-2 integrated density values after celecoxib treatment (range, 0.6-42.3; median, 12.6; P = 0.0043). The percentages of Ki67-positive tumor cells in pre-celecoxib cases ranged from 39.3 to 87.4 (median, 50.8) and were significantly higher than the percentage in the corresponding posttreatment samples (range, 27.7-83.8; median, 43.1; P = 0.0092). MVD values in pre-celecoxib biopsies ranged from 28.0 to 55.0 (median, 38.5) and were significantly higher than the corresponding values in posttreatment samples (range, 16.0-49.5; median; 27.6; P = 0.012). Also, prostaglandin E(2) levels showed a trend to be reduced after celecoxib treatment (range: 4.7-386.6 pg/mg wet tissue in pretreated cases versus 4.8-91.9 pg/mg wet tissue in posttreated cases (P = 0.092). CONCLUSIONS: In cervical cancer, celecoxib treatment decreases tumor COX-2 expression and markers of proliferation and neoangiogenesis, while being uneffective on stroma COX-2 levels, thus suggesting that selective COX-2 inhibitors may be a promising strategy not only for chemopreventive approaches but also for therapeutic approaches in this neoplasia.


Assuntos
Apoptose , Inibidores de Ciclo-Oxigenase/uso terapêutico , Isoenzimas/metabolismo , Antígeno Ki-67/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Sulfonamidas/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico , Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Adolescente , Adulto , Idoso , Antígenos de Neoplasias/metabolismo , Vasos Sanguíneos/efeitos dos fármacos , Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Celecoxib , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Dinoprostona/metabolismo , Feminino , Humanos , Técnicas Imunoenzimáticas , Linfócitos/metabolismo , Proteínas de Membrana , Pessoa de Meia-Idade , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Projetos Piloto , Pirazóis , Serpinas/metabolismo , Neoplasias do Colo do Útero/irrigação sanguínea , Neoplasias do Colo do Útero/metabolismo
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