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1.
J Biol Chem ; 298(12): 102703, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36395886

RESUMO

During prolonged mitotic arrest induced by antimicrotubule drugs, cell fate decision is determined by two alternative pathways, one leading to cell death and the other inducing premature escape from mitosis by mitotic slippage. FBWX7, a member of the F-box family of proteins and substrate-targeting subunit of the SKP1-CUL1-F-Box E3 ubiquitin ligase complex, promotes mitotic cell death and prevents mitotic slippage, but molecular details underlying these roles for FBWX7 are unclear. In this study, we report that WDR5 (WD-repeat containing protein 5), a component of the mixed lineage leukemia complex of histone 3 lysine 4 methyltransferases, is a substrate of FBXW7. We determined by coimmunoprecipitation experiments and in vitro binding assays that WDR5 interacts with FBXW7 in vivo and in vitro. SKP1-CUL1-F-Box-FBXW7 mediates ubiquitination of WDR5 and targets it for proteasomal degradation. Furthermore, we find that WDR5 depletion counteracts FBXW7 loss of function by reducing mitotic slippage and polyploidization. In conclusion, our data elucidate a new mechanism in mitotic cell fate regulation, which might contribute to prevent chemotherapy resistance in patients after antimicrotubule drug treatment.


Assuntos
Proteína 7 com Repetições F-Box-WD , Histona-Lisina N-Metiltransferase , Peptídeos e Proteínas de Sinalização Intracelular , Humanos , Proteínas de Ciclo Celular/metabolismo , Proteína 7 com Repetições F-Box-WD/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisina/metabolismo , Proteínas Ligases SKP Culina F-Box/genética , Proteínas Ligases SKP Culina F-Box/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
2.
Neurobiol Learn Mem ; 132: 1-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27108599

RESUMO

Navigation through an environment is a fundamental human activity. Although group differences in navigational ability are documented (e.g., gender), little is known about traits that predict these abilities. Apart from a well-established link between mental rotational abilities and navigational learning abilities, recent studies point to an influence of trait anxiety on the formation of internal cognitive spatial representations. However, it is unknown whether trait anxiety affects the processing of information obtained through externalized representations such as maps. Here, we addressed this question by taking into account emerging evidence indicating impaired performance in executive tasks by high trait anxiety specifically in individuals with lower executive capacities. For this purpose, we tested 104 male participants, previously characterised on trait anxiety and mental rotation ability, on a newly-designed map-based route learning task, where participants matched routes presented dynamically on a city map to one presented immediately before (same/different judgments). We predicted an interaction between trait anxiety and mental rotation ability, specifically that performance in the route learning task would be negatively affected by anxiety in participants with low mental rotation ability. Importantly, and as predicted, an interaction between anxiety and mental rotation ability was observed: trait anxiety negatively affected participants with low-but not high-mental rotation ability. Our study reveals a detrimental role of trait anxiety in map-based route learning and specifies a disadvantage in the processing of map representations for high-anxious individuals with low mental rotation abilities.


Assuntos
Ansiedade/fisiopatologia , Personalidade/fisiologia , Aprendizagem Espacial/fisiologia , Navegação Espacial/fisiologia , Adulto , Humanos , Imaginação , Masculino , Rotação , Adulto Jovem
3.
Scand J Gastroenterol ; 47(12): 1429-35, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23110405

RESUMO

OBJECTIVES AND AIMS: Histological Barrett's esophagus, defined as specialized intestinal metaplasia (SIM+) at the cardia without endoscopic suspicion of columnar epithelium, is found frequently in biopsies at the gastro-esophageal junction although its clinical relevance is unknown. The authors aim was to evaluate prospectively the progression of SIM+ to macroscopically evident Barrett's esophagus (BE/SIM+), and to identify risk factors for this progression. METHODS: Data were obtained from a sub-group of patients (no visible BE at presentation, but SIM+) included in the ProGERD study, a prospective evaluation of the clinical course of GERD under routine clinical care. They had esomeprazole 20-40 mg/day for 2-8 weeks. Symptom assessment was performed annually, and endoscopy with biopsy was planned at baseline, after healing treatment and after 2 and/or 5 years. RESULTS: 128 of 171 (74.8%) patients with unequivocal SIM at the z-line after healing were biopsied again after 2 and/or 5 years. At follow-up, 33 (25.8%) of these patients showed progression to BE/SIM+. Factors significantly associated with progression were smoking, a long history of GERD and severe esophagitis at baseline. Patients who had progressed to BE/SIM+ already at 2 years showed consistent findings at 5 years. CONCLUSION: More than 20% of GERD patients with SIM+ in this study were found to have BE/SIM+ within 2-5 years. This finding supports the hypothesis that SIM+ at the cardia could be the missing link explaining increased cancer risk in GERD patients without overt BE and merits further investigation in a prospective study.


Assuntos
Esôfago de Barrett/patologia , Cárdia/patologia , Junção Esofagogástrica/patologia , Refluxo Gastroesofágico/patologia , Adulto , Idoso , Esôfago de Barrett/etiologia , Biópsia , Intervalos de Confiança , Endoscopia Gastrointestinal , Esomeprazol/uso terapêutico , Esofagite/etiologia , Feminino , Seguimentos , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/tratamento farmacológico , Humanos , Masculino , Metaplasia , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Inibidores da Bomba de Prótons/uso terapêutico , Fumar , Fatores de Tempo
4.
Phys Chem Chem Phys ; 13(15): 7136-41, 2011 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-21399810

RESUMO

Recently we developed an access to metal- and metal-oxide colloids based on thermal evaporation of metals into ionic liquids (ILs). Here we present systematic studies on the long-time stability of gold and copper nanoparticles (NPs) in different ILs. The influence of metal concentration and temperature on the ripening of the as-prepared gold NPs in different ILs was investigated by transmission electron microscopy (TEM) and UV-vis absorption measurements. Short alkyl chain-length-methyl-imidazolium salts with weakly coordinating perfluorinated counter anions (PF(6), BF(4) or Tf(2)N, bis(trifluoromethanesulfonyl)amide) were found to be better stabilizers compared to ILs with cations bearing long alkyl chains (trihexyltetradecylphosphonium, 1-octyl-3-methylimidazolium) and anions of higher coordination strength (DCA, dicyanamide). In the latter ILs fast particle growth and agglomeration was observed. In the well-stabilizing ILs initially very small NPs form which undergo a similar ripening process at room temperature as at higher temperatures. The final particle size depends largely on the used IL and the metal and to a minor extent on the temperature. The metal concentration seems to be an unimportant factor.

5.
Cell Death Differ ; 27(2): 758-772, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31285543

RESUMO

Cell fate decision upon prolonged mitotic arrest induced by microtubule-targeting agents depends on the activity of the tumor suppressor and F-box protein FBXW7. FBXW7 promotes mitotic cell death and prevents premature escape from mitosis through mitotic slippage. Mitotic slippage is a process that can cause chemoresistance and tumor relapse. Therefore, understanding the mechanisms that regulate the balance between mitotic cell death and mitotic slippage is an important task. Here we report that FBXW7 protein levels markedly decline during extended mitotic arrest. FBXO45 binds to a conserved acidic N-terminal motif of FBXW7 specifically under a prolonged delay in mitosis, leading to ubiquitylation and subsequent proteasomal degradation of FBXW7 by the FBXO45-MYCBP2 E3 ubiquitin ligase. Moreover, we find that FBXO45-MYCBP2 counteracts FBXW7 in that it promotes mitotic slippage and prevents cell death in mitosis. Targeting this interaction represents a promising strategy to prevent chemotherapy resistance.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas F-Box/metabolismo , Proteína 7 com Repetições F-Box-WD/metabolismo , Mitose , Ubiquitina-Proteína Ligases/metabolismo , Morte Celular , Humanos , Células Tumorais Cultivadas
6.
Chem Commun (Camb) ; (3): 301-3, 2009 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-19209309

RESUMO

The environmentally friendly ionic liquid N-(2-hydroxyethyl)ammonium formate works as a reaction medium, reducing and templating agent in the mild microwave synthesis (5 min, 80 degrees C) of a macroporous silver framework from AgNO(3).

7.
Cogn Res Princ Implic ; 4(1): 5, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30758681

RESUMO

Navigation systems are ubiquitous tools to assist wayfinders of the mobile information society with various navigational tasks. Whenever such systems assist with self-localization and path planning, they reduce human effort for navigating. Automated navigation assistance benefits navigation performance, but research seems to show that it negatively affects attention to environment properties, spatial knowledge acquisition, and retention of spatial information. Very little is known about how to design navigation systems for pedestrian navigation that increase both navigation performance and spatial knowledge acquisition. To this end, we empirically tested participants (N = 64) using four different navigation system behaviors (between-subject design). Two cognitive processes with varying levels of automation, self-localization and allocation of attention, define navigation system behaviors: either the system automatically executes one of the processes (high level of automation), or the system leaves the decision of when and where to execute the process to the navigator (low level of automation). In two experimental phases, we applied a novel empirical framework for evaluating spatial knowledge acquisition in a real-world outdoor urban environment. First, participants followed a route assisted by a navigation system and, simultaneously, incidentally acquired spatial knowledge. Second, participants reversed the route using the spatial knowledge acquired during the assisted phase, this time without the aid of the navigation system. Results of the route-following phase did not reveal differences in navigation performance across groups using different navigation system behaviors. However, participants using systems with higher levels of automation seemed not to acquire enough spatial knowledge to reverse the route without navigation errors. Furthermore, employing novel methods to analyze mobile eye tracking data revealed distinct patterns of human gaze behavior over time and space. We thus can demonstrate how to increase spatial knowledge acquisition without harming navigation performance when using navigation systems, and how to influence human navigation behavior with varying navigation system behavior. Thus, we provide key findings for the design of intelligent automated navigation systems in real-world scenarios.

8.
Lancet Respir Med ; 6(2): 117-126, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29331313

RESUMO

BACKGROUND: The peripheral blood eosinophil count might help identify those patients with chronic obstructive pulmonary disease (COPD) who will experience fewer exacerbations when taking inhaled corticosteroids (ICS). Previous post-hoc analyses have proposed eosinophil cutoffs that are both arbitrary and limited in evaluating complex interactions of treatment response. We modelled eosinophil count as a continuous variable to determine the characteristics that determine both exacerbation risk and clinical response to ICS in patients with COPD. METHODS: We analysed data from three AstraZeneca randomised controlled trials of budesonide-formoterol in patients with COPD with a history of exacerbations and available blood eosinophil counts. Patients with any history of asthma were excluded. Negative binomial regression analysis was done using splines for modelling of continuous variables to study the primary outcome of annual exacerbation rate adjusted for exposure time and study design. The trials are registered with ClinicalTrials.gov, NCT00206167, NCT00206154, and NCT00419744. FINDINGS: 4528 patients were studied. A non-linear increase in exacerbations occurred with increasing eosinophil count in patients who received formoterol alone. At eosinophil counts of 0·10 × 109 cells per L or more, a significant treatment effect was recorded for exacerbation reduction with budesonide-formoterol compared with formoterol alone (rate ratio 0·75, 95% CI 0·57-0·99; pinteraction=0·015). Interactions were observed between eosinophil count and the treatment effects of budesonide-formoterol over formoterol on St George's Respiratory Questionnaire (pinteraction=0·0043) and pre-bronchodilator FEV1 (linear effect p<0·0001, pinteraction=0·067). Only eosinophil count and smoking history were independent predictors of response to budesonide-formoterol in reducing exacerbations (eosinophil count, pinteraction=0·013; smoking history, pinteraction=0·015). INTERPRETATION: In patients with COPD treated with formoterol, blood eosinophil count predicts exacerbation risk and the clinical response to ICS. FUNDING: AstraZeneca.


Assuntos
Broncodilatadores/uso terapêutico , Budesonida/uso terapêutico , Eosinófilos , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Broncodilatadores/efeitos adversos , Broncodilatadores/sangue , Budesonida/efeitos adversos , Budesonida/sangue , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Terapêutica
9.
Respir Med ; 101(10): 2065-75, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17643277

RESUMO

The safety and tolerability of indacaterol, a novel once-daily beta(2)-agonist bronchodilator with a fast onset of action, were assessed in 156 asthma patients in a multicentre, randomized, double-blind, placebo-controlled study. Patients received indacaterol 200, 400 or 600 microg or placebo once daily for 28 days. Adverse events (AEs), laboratory assessments, vital signs, electrocardiograms, spirometry and physical examinations were monitored. Indacaterol pharmacokinetics were assessed. There was no evidence of dose-related increases in AE incidence or clinically significant hypokalaemia or hyperglycaemia in indacaterol-treated patients. Mean pulse rate changes were minor in any group, with maximum 1-h post-dose changes from baseline of -3.7, -3.3 and -2.2 bpm for indacaterol 200, 400 and 600 microg, respectively, and -2.9 bpm for placebo. Mean QTc interval was similar between groups; change from baseline >60 ms occurred in only two patients. Mean FEV(1) increased after the first indacaterol dose; baseline-adjusted pre-dose (trough) values remained >or=166 mL higher than placebo at all subsequent visits, supporting a 24-h bronchodilator effect. Pre-dose (but not post-dose) serum indacaterol concentrations indicated a slight trend for accumulation. Once-daily indacaterol 200-600 microg has a favourable therapeutic index. It is well tolerated, and is not associated with any adverse cardiac or metabolic effects, while providing effective 24-h bronchodilation.


Assuntos
Asma/tratamento farmacológico , Broncodilatadores/farmacocinética , Indanos/farmacocinética , Quinolonas/farmacocinética , Adolescente , Adulto , Idoso , Broncodilatadores/administração & dosagem , Broncodilatadores/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Indanos/administração & dosagem , Indanos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Quinolonas/administração & dosagem , Quinolonas/efeitos adversos , Espirometria/métodos , Resultado do Tratamento
10.
Cell Cycle ; 15(24): 3419-3431, 2016 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-27754753

RESUMO

Topoisomerase IIα is an essential enzyme that resolves topological constraints in genomic DNA. It functions in disentangling intertwined chromosomes during anaphase leading to chromosome segregation thus preserving genomic stability. Here we describe a previously unrecognized mechanism regulating topoisomerase IIα activity that is dependent on the F-box protein Fbxo28. We find that Fbxo28, an evolutionarily conserved protein, is required for proper mitotic progression. Interfering with Fbxo28 function leads to a delay in metaphase-to-anaphase progression resulting in mitotic defects as lagging chromosomes, multipolar spindles and multinucleation. Furthermore, we find that Fbxo28 interacts and colocalizes with topoisomerase IIα throughout the cell cycle. Depletion of Fbxo28 results in an increase in topoisomerase IIα-dependent DNA decatenation activity. Interestingly, blocking the interaction between Fbxo28 and topoisomerase IIα also results in multinucleated cells. Our findings suggest that Fbxo28 regulates topoisomerase IIα decatenation activity and plays an important role in maintaining genomic stability.


Assuntos
Antígenos de Neoplasias/metabolismo , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Mitose , Proteínas Ligases SKP Culina F-Box/metabolismo , Sequência de Aminoácidos , Cromossomos Humanos/metabolismo , Sequência Conservada , Regulação para Baixo , Evolução Molecular , Deleção de Genes , Células HEK293 , Células HeLa , Humanos , Ligação Proteica , Proteínas Ligases SKP Culina F-Box/química
11.
Lancet Respir Med ; 4(10): 797-806, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27574788

RESUMO

BACKGROUND: Airway neutrophilic inflammation is a pathological feature in some patients with severe asthma. Stimulation of the chemokine receptor CXCR2 mediates neutrophil migration into the airways. We investigated the safety and efficacy of AZD5069, a CXCR2 antagonist, as an add-on therapy in patients with uncontrolled severe asthma. METHODS: In this multicentre, randomised, double-blind, placebo-controlled, dose-finding trial, we enrolled patients aged 18 years or older with uncontrolled asthma despite combination therapy with long-acting ß2 agonists and medium-dose or high-dose inhaled corticosteroids. Patients were randomised in a 1:1:1:1 ratio via an interactive voice-response or web-response system to receive 5, 15, or 45 mg oral AZD5069 twice daily or matched placebo. The primary endpoint was the number of severe asthma exacerbations in 6 months. Safety was assessed in the 6-month treatment period and an optional 6-month safety extension. This trial is registered with ClinicalTrials.gov, number NCT01704495. FINDINGS: 640 patients with a mean age of 52 (SD 11·8) years were randomised, 478 to receive AZD5069 (5 mg n=160, 15 mg n=156, and 45 mg n=162) and 162 placebo. No dose of AZD5069 reduced the rate of severe exacerbations compared with placebo (rate ratio for 5 mg 1·29, 90% CI 0·79-2·11; for 15 mg 1·53, 0·95-2·46; and for 45 mg 1·56, 0·98-2·49). Treatment with AZD5069 was generally well tolerated. The most commonly reported adverse event overall was nasopharyngitis, seen in 18 (11·5%) receiving 5 mg, 13 (8·5%) receiving 15 mg, and 18 (11·2%) receiving 45 mg AZD5069, and 31 (19·5%) of those receiving placebo. INTERPRETATION: Treatment with this selective CXCR2 antagonist did not reduce the frequency of severe exacerbations in patients with uncontrolled severe asthma. These findings bring into question the role of CXCR2-mediated neutrophil recruitment in the pathobiology of exacerbations in severe refractory asthma. FUNDING: AstraZeneca.


Assuntos
Corticosteroides/administração & dosagem , Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Pirimidinas/administração & dosagem , Sulfonamidas/administração & dosagem , Administração por Inalação , Corticosteroides/efeitos adversos , Adulto , Antiasmáticos/efeitos adversos , Progressão da Doença , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringite/induzido quimicamente , Pirimidinas/efeitos adversos , Sulfonamidas/efeitos adversos , Resultado do Tratamento
12.
Chest ; 128(3): 1168-78, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16162703

RESUMO

STUDY OBJECTIVES: We have previously shown that tiotropium at 18 mug reduces lung hyperinflation and dyspnea during exercise and improves exercise tolerance in patients with COPD. The present study was designed to gain further insight into the duration of improvements. DESIGN, PATIENTS, AND INTERVENTIONS: A randomized, double-blind, placebo-controlled, parallel-group study was conducted in 261 COPD patients (mean age, 62.5 +/- 7.4 years [+/- SD]; 189 men and 72 women; mean FEV1, 1.2 +/- 0.4 L [43 +/- 12.7% predicted]). On day 0 (first dose), day 21, and day 42 of treatment, pulmonary function tests were performed before and 1 h 20 min after dosing, followed by a constant work rate cycle ergometry test (75% maximum work capacity) to symptom limitation at 2.25 h after dosing. On day 42, an additional constant work rate cycle ergometry test was performed at 8 h after dosing. RESULTS: Adjusted mean (+/- SE) endurance time (ET) on day 42 was 803 +/- 40 s (tiotropium), vs 568 +/- 42 s (placebo) at 2.25 h after dosing (primary end point; treatment difference, 236 +/- 58 s; p = 0.0001) and 665 +/- 40 s (tiotropium) vs 494 +/- 42 s (placebo) at 8 h after dosing (treatment difference, 171 +/- 58 s; p = 0.0035). Adjusted mean dyspnea intensity at isotime on day 42 was 4.60 +/- 0.16 Borg units (tiotropium), vs 5.65 +/- 0.16 Borg units (placebo) at 2.25 h after dosing (p < 0.001), and 5.54 +/- 0.17 Borg units (tiotropium) vs 6.51 +/- 0.18 Borg units (placebo) at 8 h after dosing (p < 0.001). Adjusted mean pre-exercise inspiratory capacity (IC) on day 42 was 2.41 +/- 0.03 L (tiotropium) vs 2.19 +/- 0.03 L (placebo) at 2.25 h after dosing (p < 0.001), and 2.31 +/- 0.03 L (tiotropium) vs 2.16 +/- 0.03 L (placebo) at 8 h after dosing (p < 0.001). The significant increase in IC with tiotropium compared with placebo was maintained throughout exercise. CONCLUSIONS: The present study confirms that tiotropium reduces lung hyperinflation at rest and during exercise, reduces exertional dyspnea, and improves symptom-limited exercise tolerance in COPD patients. Furthermore, this study shows that this improvement is present at 2.25 h and at 8 h after dosing after 6 weeks of treatment.


Assuntos
Broncodilatadores/farmacologia , Tolerância ao Exercício/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Derivados da Escopolamina/farmacologia , Idoso , Broncodilatadores/uso terapêutico , Método Duplo-Cego , Teste de Esforço , Feminino , Humanos , Masculino , Testes de Função Respiratória , Derivados da Escopolamina/uso terapêutico , Fatores de Tempo , Brometo de Tiotrópio , Resultado do Tratamento
13.
J Clin Pharmacol ; 45(2): 146-52, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15647406

RESUMO

Ciclesonide is a novel inhaled corticosteroid that is converted in the lungs to its active metabolite, desisobutyryl-ciclesonide (des-CIC). The aim of this study was to compare the deposition of ciclesonide, as well as its conversion to des-CIC, in the oropharyngeal cavity with fluticasone propionate (FP) following inhalation via hydrofluoroalkane-propelled metered-dose inhalers (HFA-MDIs). Eighteen asthmatics inhaled ciclesonide 800 microg followed by FP 1000 microg or vice versa in an open, randomized, 2-treatment, 2-sequence study design. The oropharynx was washed out immediately and at 15, 30, 45, and 60 minutes after inhalation. Samples were analyzed for ciclesonide, des-CIC, and FP using liquid chromatography with tandem mass-spectrometric detection. Concentration-time curves and area under the concentration-time curve (AUC) were calculated for each drug. Ciclesonide and FP were recovered in almost all samples. Within 60 minutes after inhalation, the amounts of both ciclesonide and FP decreased sharply, and low residual levels were detected after 30 minutes. des-CIC was detected in relatively low concentrations, with maximum concentration 30 minutes following inhalation. The AUC(0-60 min) for ciclesonide (250.4 nmol x h/L) and des-CIC (37.8 nmol x h/L) were found to be significantly lower compared with FP (636.2 nmol.h/L, P < .001). Approximately 50% less ciclesonide and 90% less metabolite were present in the oropharynx compared with FP. Less than 20% of the residual ciclesonide in the oropharynx was metabolized to des-CIC. These findings indicate that oropharyngeal deposition of ciclesonide is only half that of FP following inhalation from an HFA-MDI. Furthermore, there is little activation of ciclesonide to its active metabolite in the oropharynx, suggesting a decreased likelihood of inhaled ciclesonide-associated oropharyngeal side effects.


Assuntos
Administração por Inalação , Androstadienos/administração & dosagem , Androstadienos/metabolismo , Orofaringe/efeitos dos fármacos , Orofaringe/metabolismo , Pregnenodionas/administração & dosagem , Pregnenodionas/metabolismo , Adulto , Androstadienos/uso terapêutico , Área Sob a Curva , Asma/diagnóstico , Asma/tratamento farmacológico , Cromatografia Líquida/métodos , Tosse/induzido quimicamente , Esquema de Medicação , Etanol/química , Feminino , Fluticasona , Humanos , Masculino , Espectrometria de Massas/métodos , Inaladores Dosimetrados , Pregnenodionas/uso terapêutico , Soluções/química , Irrigação Terapêutica/métodos , Fatores de Tempo
14.
J Clin Pharmacol ; 45(5): 498-503, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15831772

RESUMO

This study aimed to test the utility of the ozone challenge model for profiling novel compounds designed to reduce airway inflammation. The authors used a randomized, double-dummy, double-blind, placebo-controlled 3-period crossover design alternating single orally inhaled doses of fluticasone propionate (inhaled corticosteroids, 2 mg), oral prednisolone (oral corticosteroids, 50 mg), or matched placebo. At a 2-week interval, 18 healthy ozone responders (>10% increase in sputum neutrophils) underwent a 3-hour ozone (250 ppb)/intermittent exercise challenge starting 1 hour after drug treatment. Airway inflammation was assessed at 2 hours (breath condensate) and 3 hours (induced sputum) after ozone challenge. Compared to placebo, pretreatment with inhaled corticosteroids or oral corticosteroids resulted in a significant reduction (mean [95% confidence interval]) of sputum neutrophils by 62% (35%, 77%) and 64% (39%, 79%) and of sputum supernatant myeloperoxidase by 55% (41%, 66%) and 42% (25%, 56%), respectively. The authors conclude that an optimized ozone challenge model (including ozone responders and ensuring adequate drug levels during exposure) may be useful for testing novel anti-inflammatory compounds in early development.


Assuntos
Testes de Provocação Brônquica/métodos , Avaliação de Medicamentos/métodos , Ozônio , Administração por Inalação , Administração Oral , Adulto , Androstadienos/administração & dosagem , Androstadienos/farmacologia , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Fluticasona , Humanos , Masculino , Modelos Biológicos , Prednisolona/administração & dosagem , Prednisolona/farmacologia , Testes de Função Respiratória , Escarro/citologia , Escarro/metabolismo
15.
Pharmacoeconomics ; 23(7): 723-31, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15987228

RESUMO

OBJECTIVES: To compare the costs and effectiveness of adjustable maintenance dosing with budesonide/formoterol in a single inhaler versus fixed dosing in adults with asthma. METHODS: In this prospective, randomised, open-label, parallel-group, multicentre trial conducted in Germany, patients with asthma received budesonide/formoterol 160 microg/4.5 microg in a single inhaler (Symbicort Turbuhaler with two inhalations twice daily for a 4-week run-in period. Patients were then randomised to either adjustable maintenance dosing (one inhalation twice daily, stepping up to four inhalations twice daily for 1 week if asthma worsened; n=1679) or fixed dosing (two inhalations twice daily; n=1618) for 12 weeks. The primary efficacy variable was the change in health-related quality of life (HR-QOL), measured using the Asthma Quality of Life Questionnaire (standardised) during the randomised treatment period. Resource utilisation data were collected in parallel and combined with German unit costs to estimate direct and indirect costs (year 2001 values). RESULTS: Both treatment regimens were equally effective in maintaining HR-QOL and asthma control during the randomised treatment period. However, overall, patients in the adjustable maintenance dosing group took fewer daily inhalations of budesonide/formoterol than those in the fixed-dosing group (mean: 2.63 vs 3.82 inhalations; p<0.001). Adjustable maintenance dosing was associated with significantly lower asthma-related direct costs compared with fixed dosing (mean: 221 euro vs 292 euro; p<0.001). This pattern was maintained when patients were stratified into those with peak expiratory flow (PEF) of 60% to <80% predicted normal and those with PEF of>/=80% predicted normal and when total costs were considered. CONCLUSION: Adjustable maintenance dosing with budesonide/formoterol in a single inhaler maintained HR-QOL in adult patients with asthma at a significantly lower cost than fixed dosing.


Assuntos
Asma/tratamento farmacológico , Asma/economia , Broncodilatadores/economia , Broncodilatadores/uso terapêutico , Budesonida/economia , Etanolaminas/economia , Atenção Primária à Saúde/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Broncodilatadores/administração & dosagem , Budesonida/administração & dosagem , Budesonida/uso terapêutico , Análise Custo-Benefício , Esquema de Medicação , Combinação de Medicamentos , Etanolaminas/administração & dosagem , Etanolaminas/uso terapêutico , Feminino , Fumarato de Formoterol , Alemanha , Humanos , Masculino , Inaladores Dosimetrados , Pessoa de Meia-Idade , Qualidade de Vida
17.
Biol Open ; 4(3): 370-7, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25701666

RESUMO

Duplication of centrioles, namely the formation of a procentriole next to the parental centriole, is regulated by the polo-like kinase Plk4. Only a few other proteins, including STIL (SCL/TAL1 interrupting locus, SIL) and Sas-6, are required for the early step of centriole biogenesis. Following Plk4 activation, STIL and Sas-6 accumulate at the cartwheel structure at the initial stage of the centriole assembly process. Here, we show that STIL interacts with Plk4 in vivo. A STIL fragment harboring both the coiled-coil domain and the STAN motif shows the strongest binding affinity to Plk4. Furthermore, we find that STIL is phosphorylated by Plk4. We identified Plk4-specific phosphorylation sites within the C-terminal domain of STIL and show that phosphorylation of STIL by Plk4 is required to trigger centriole duplication.

18.
Respir Med ; 98 Suppl B: S22-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15481285

RESUMO

Effective inhalation therapy using pressurised metered dose inhalers (pMDIs) and dry powder inhalers (DPIs) is the cornerstone of asthma management. Previous studies have demonstrated difficulties in the usage of pMDIs in certain patient groups, especially as pMDis require the co-ordination of inhaler activation with dose inhalation. Almost all DPIs are breath-activated and preclude the need to co-ordinate activation with inspiration. Three key parameters for successful inhaler use should be considered when evaluating existing or future DPI devices: (1) compliance; (2) fine particle distribution and dependency on inspiratory flow and; (3) clinical efficacy. A threshold mechanism which controls for a minimal inspiratory flow rate is desirable in order to support formation of an optimal fine particle fraction (FPF) which in turn improves lung deposition. Additionally, in order to enhance patient compliance an optimal multidose DPI should feature a visual or acoustic feedback of a correct inhalation. The Novolizer is a multidose refillable DPI. It has multiple feedback mechanisms and a trigger flow valve system, which helps to ensure correct inhalation that allows adequate lung deposition, helps to reassure the patient that medication has been taken and might therefore improve patient compliance. The low-to-medium airflow resistance translates into higher peak inspiratory flow (PIF) and makes the Novolizer DPI particularly suitable for the use in patients with reduced inspiratory flow rates. Clinical studies have shown that children, elderly patients, adults with moderate-to-severe asthma and COPD patients (stage IIa-III) are able to generate sufficient inspiratory flow to operate the Novolizer effectively. In contrast previous studies with other MDPIs (e.g. Turbuhaler or Aerolizer) demonstrated that in patient groups with severe obstructive lung disease or in children with asthma optimal inspiratory flow rates are not achieved in all patients.


Assuntos
Asma/tratamento farmacológico , Inaladores Dosimetrados/normas , Administração por Inalação , Retroalimentação , Humanos , Tamanho da Partícula , Cooperação do Paciente , Pós/administração & dosagem
19.
J Expo Anal Environ Epidemiol ; 13(2): 152-60, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12679795

RESUMO

Measurements of biocontaminants in settled house dust once a year are commonly used to assess long-term exposure. To examine stability over time and seasonal variation, we measured concentrations of mite and cat allergens, endotoxin and mold spores in living room floor dust in 745 German homes collected twice a year in two different seasons. The study population consisted of adults and children living in five different areas in Germany. All dust samples were collected in a standardized manner from the living room floor and taken during the years 1995 to 1998. The median interval between the two dust samplings was approximately 7 months. Mite and cat allergens were measured in settled house dust by monoclonal antibodies, endotoxin by the limulus amebocyte lysate method, and total spore counts by cultural methods. Crude Pearson's correlation coefficients between log-transformed concentrations in the first and second dust samples ranged between 0.65 and 0.75 for allergens, 0.59 for endotoxin and only 0.06 for total spore counts. The strongest and most consistent seasonal effects were observed for fungi with highest levels in July-September. Cat allergen concentrations were found consistently to be increased in January-March. Mite allergens did not show a strong and consistent seasonal pattern. We conclude that repeated measurements of mite and cat allergens and endotoxin in settled house dust improve the estimate for annual mean concentrations. However, even a single observation of these biocontaminants may be a good proxy for a 1-year exposure since repeated measures were highly correlated. However, repeated measurements of fungi levels were only weakly correlated and thus repeated observations for assessment of annual means of total spore counts are needed.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Alérgenos/análise , Endotoxinas/análise , Exposição Ambiental , Monitoramento Ambiental/normas , Fungos , Animais , Poeira , Monitoramento Ambiental/estatística & dados numéricos , Habitação , Humanos , Ácaros , Reprodutibilidade dos Testes , Medição de Risco , Estações do Ano
20.
Pulm Pharmacol Ther ; 21(1): 61-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17239638

RESUMO

OBJECTIVES: Histamine and cysteinyl leukotrienes play an important role in early (EAR) and late (LAR) allergen reactions. Although protection by anti-histamines and anti-leukotrienes has been studied extensively, little is known about the effect of their combination. We, therefore, assessed the effect of clinically recommended doses of azelastine and montelukast alone and in combination on EAR and LAR. METHODS: Seventeen patients (mean age 31 years, 14 m/3 f) with asthma and proven EAR and LAR received an oral dose of 4 mg azelastine twice daily, or 10mg montelukast once daily, or both for 1 week, in a double-blind, double-dummy, cross-over fashion. FEV(1) was measured after single-dose allergen challenges during EAR (0-2h) and LAR (2-9h). RESULTS: Azelastine, montelukast and their combination protected against both EAR and LAR (p<0.004, each) by 46% and 43%, 76% and 59%, and 89% and 78%, respectively. Azelastine was not as effective during EAR but equally effective to montelukast during LAR. The combination was superior to each drug alone during both EAR and LAR (p<0.05, each). CONCLUSION: The combination of azelastine and montelukast in clinically recommended doses has a greater effect in suppressing early and late allergen reactions than each drug alone.


Assuntos
Acetatos/uso terapêutico , Antialérgicos/uso terapêutico , Asma/tratamento farmacológico , Broncoconstrição/efeitos dos fármacos , Ftalazinas/uso terapêutico , Quinolinas/uso terapêutico , Acetatos/administração & dosagem , Adulto , Antialérgicos/administração & dosagem , Testes de Provocação Brônquica , Estudos Cross-Over , Ciclopropanos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ftalazinas/administração & dosagem , Quinolinas/administração & dosagem , Testes de Função Respiratória , Sulfetos
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