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1.
Eur Respir J ; 45(2): 511-24, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25537559

RESUMO

The use of noninferiority randomised trials for patients with advanced non-small cell lung cancer has emerged during the past 10-15 years but has raised some issues related to their justification and methodology. The present systematic review aimed to assess trial characteristics and methodological aspects. All randomised clinical trials with a hypothesis of noninferiority/equivalence, published in English, were identified. Several readers extracted a priori defined methodological information. A qualitative analysis was then performed. We identified 20 randomised clinical trials (three phase II and 17 phase III), 11 of them being conducted in strong collaboration with industry. We highlighted some deficiencies in the reports like the lack of justification for both the noninferiority assumption and the definition of the noninferiority margin, as well as inconsistencies between the results and the authors' conclusions. CONSORT guidelines were better followed for general items than for specific items (p<0.001). Improvement in the reporting of the meth"odology of noninferiority/equivalence trials is needed to avoid misleading interpretation and to allow readers to be fully aware of the assumptions underlying the trial designs. They should be restricted to limited specific situations with a strong justification why a noninferiority hypothesis is acceptable.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Algoritmos , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Humanos , Oncologia/métodos , Reprodutibilidade dos Testes , Projetos de Pesquisa , Risco
2.
Anal Chim Acta ; 672(1-2): 30-9, 2010 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-20579486

RESUMO

Microbiological inhibition screening tests could play an important role to detect residues of antibiotics in the different animal food products, but very few are available for the aquaculture products in general, and for shrimps in particular. A two-plate microbiological method to screen shrimp for residues of the most commonly used antibiotics has been developed and validated according to criteria derived from the European Commission Decision 2002/657/CE. Bacillus subtilis was used as a sensitive strain to target antibiotics. Culture conditions on Petri plates (pH of medium) were selected to enhance the capacity of antibiotic detection. Antibiotic residues were extracted from shrimps using acetonitrile/acetone (70/30, v/v) before application on Petri plates seeded with B. subtilis. The method was validated using spiked blank tissues as well as antibiotic treated shrimps with enrofloxacin and tetracycline, two antibiotics often found to be used in shrimp production. For tetracyclines and (fluoro)quinolones, the detection capability was below the maximum residue limit (MRL), while it was around the MRL for sulfonamides. The specificity of the microbiological screening was 100% in all cases while the sensitivity and accuracy was 100% in almost all cases. The capacity of the method to detect contaminated samples was confirmed on antibiotic treated shrimps, analyzed in parallel with a confirmatory method (Liquid Chromatography coupled to mass spectrometry (LC-MS)).


Assuntos
Antibacterianos/análise , Resíduos de Drogas/análise , Contaminação de Alimentos/análise , Testes de Sensibilidade Microbiana/métodos , Palaemonidae/química , Animais , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Resíduos de Drogas/farmacologia , Sensibilidade e Especificidade
3.
Anal Chim Acta ; 633(2): 293-9, 2009 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-19166736

RESUMO

High performance liquid chromatography coupled to an ultraviolet, diode array or fluorescence detector (HPLC/UV-FLD) has been used to set up a method to detect the 15(+1) EU priority polycyclic aromatic hydrocarbons (PAHs) in food supplements covering the categories of dried plants and plant extracts excluding oily products. A mini validation was performed and the following parameters have been determined: limit of detection, limit of quantification, precision, recovery and linearity. They were in close agreement with quality criteria described in the Commission Regulation (EC) No 333/2007 concerning the PAH benzo[a]pyrene in foodstuffs, except the not fluorescent cyclopenta[c,d]pyrene for which the UV detection leads to a higher limit of detection. Analysis of twenty commercial food supplements covering mainly the class of dried plants was performed to evaluate their PAHs contamination levels and to test the applicability of the method to various plant matrices. Fifty percent of analyzed samples showed concentration exceeding 2 microgkg(-1) for one or more PAHs.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Fracionamento Químico , União Europeia , Reprodutibilidade dos Testes , Solventes/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
4.
Chemosphere ; 77(11): 1577-84, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19836822

RESUMO

The aim of this study was to assess the adverse effects of enrofloxacin (EF) on Tra catfish, Pangasianodon hypophthalmus, in relation with density stress. Fish were held at 40, 80 or 120 fish m(-3) and fed with pellets containing either 1 g kg(-1) EF or no EF. Antibiotic exposure lasted 7d and all fish were fed without EF for another 7-d recovery period. Fish were sampled at 3, 7, 8, 10 and 14 d after the beginning of EF exposure. Lipid peroxidation (LPO) and total glutathione (GSH) levels, catalase (CAT), glutathione-s-transferase (GST) and acetylcholine-esterase (AChE) activities were assessed in gill, brain, liver and muscle. At day 7, LPO levels in gills of EF-fish reared at low or high density were significantly more than 5-fold higher than their respective control. On the contrary, LPO in gills of EF-fish reared at medium density was significantly 3-fold lower than the control fish. Similarly, CAT activities in gills of EF-fish reared under low or high density were higher than in their control groups, while this activity was lower in EF-fish of the medium density group. AChE activities in muscles of EF-fish reared at low or high density were lower than controls at days 3 and 7, respectively. These results suggest that EF exposure may lead to disorders like lipid peroxidation and neural dysfunction in fish. However, when reared under lower stress condition (medium density), they may cope better with EF-induced stress than chronically stressed fish (low or high density).


Assuntos
Antineoplásicos/toxicidade , Peixes-Gato/metabolismo , Fluoroquinolonas/toxicidade , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Catalase/metabolismo , Ciprofloxacina/toxicidade , Enrofloxacina , Exposição Ambiental , Brânquias/enzimologia , Brânquias/metabolismo , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Cinética , Peroxidação de Lipídeos/efeitos dos fármacos
5.
Anal Chim Acta ; 589(2): 159-65, 2007 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-17418176

RESUMO

The number of substances with beta-agonistic activity, illegally introduced in meat production or in sports doping as anabolic or beta-blocking agents is increasing. Analytical methods suited for their multianalyte detection are thus necessary. In this perspective, receptor assays were developed. The research activities undertaken in this study describe the solubilisation of a recombinant human beta(2)-adrenergic receptor produced in the inner membrane of genetically modified Escherichia coli, using the detergent n-dodecyl-beta-d-maltoside. Its potential to detect the presence of beta-agonists or beta-blockers in biological samples was evaluated. The solubilised beta(2)-adrenergic receptor retained its binding affinity in a radio-receptor assay based on the competition for the binding to receptors between a ligand (beta-agonist or antagonist) and the radioligand [(125)I]iodocyanopindolol. The IC(50) values ranged from 5+/-1 x 10(-8) M (clenbuterol) to 8+/-2 x 10(-6) M (isoxsuprine) for the beta-agonists tested and from 1.5+/-0.2 x 10(-10) M (carazolol) to 1.2+/-0.2 x 10(-5) M (metoprolol) for the beta-blockers tested. It was shown to have a lower limit of detection than a radio-receptor assay using the solubilised beta(2)-adrenoceptor expressed in a mammalian cell line. The solubilised recombinant human beta(2)-adrenoreceptor expressed in E. coli would be a useful tool to develop non radioactive multianalyte screening methods.


Assuntos
Agonistas Adrenérgicos beta/análise , Antagonistas Adrenérgicos beta/análise , Receptores Adrenérgicos beta 2/metabolismo , Animais , Escherichia coli/genética , Ligação Proteica , Receptores Adrenérgicos beta 2/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Padrões de Referência , Solubilidade
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