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1.
J Neurophysiol ; 122(3): 994-1001, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31291140

RESUMO

High-frequency burstlike electrical conditioning stimulation (HFS) applied to human skin induces an increase in mechanical pinprick sensitivity of the surrounding unconditioned skin (a phenomenon known as secondary hyperalgesia). The present study assessed the effect of frequency of conditioning stimulation on the development of this increased pinprick sensitivity in humans. In a first experiment, we compared the increase in pinprick sensitivity induced by HFS, using monophasic non-charge-compensated pulses and biphasic charge-compensated pulses. High-frequency stimulation, traditionally delivered with non-charge-compensated square-wave pulses, may induce a cumulative depolarization of primary afferents and/or changes in pH at the electrode-tissue interface due to the accumulation of a net residue charge after each pulse. Both could contribute to the development of the increased pinprick sensitivity in a frequency-dependent fashion. We found no significant difference in the increase in pinprick sensitivity between HFS delivered with charge-compensated and non-charge-compensated pulses, indicating that the possible contribution of charge accumulation when non-charge-compensated pulses are used is negligible. In a second experiment, we assessed the effect of different frequencies of conditioning stimulation (5, 20, 42, and 100 Hz) using charge-compensated pulses on the development of increased pinprick sensitivity. The maximal increase in pinprick sensitivity was observed at intermediate frequencies of stimulation (20 and 42 Hz). It is hypothesized that the stronger increase in pinprick sensitivity at intermediate frequencies may be related to the stronger release of substance P and/or neurokinin-1 receptor activation expressed at lamina I neurons after C-fiber stimulation.NEW & NOTEWORTHY Burstlike electrical conditioning stimulation applied to human skin induces an increase in pinprick sensitivity in the surrounding unconditioned skin (a phenomenon referred to as secondary hyperalgesia). Here we show that the development of the increase in pinprick sensitivity is dependent on the frequency of the burstlike electrical conditioning stimulation.


Assuntos
Condicionamento Psicológico/fisiologia , Hiperalgesia/fisiopatologia , Nociceptividade/fisiologia , Pele/fisiopatologia , Percepção do Tato/fisiologia , Adolescente , Adulto , Estimulação Elétrica , Feminino , Humanos , Masculino , Adulto Jovem
2.
Clin Pharmacol Ther ; 100(6): 594-597, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27530105

RESUMO

Adaptive pathways for medicines have gained momentum and, in Europe, adaptive pathways have recently been introduced into the European Medicines Agency (EMA) processes after a successful 2-year pilot. Although the concept, as initially proposed, contained several elements that would have required regulatory reforms, the adaptive pathways program has developed a more pragmatic scope (Box 1). In this article, we explore the main challenges and opportunities adaptive pathways pose from a European health technology assessment (HTA) perspective.


Assuntos
Aprovação de Drogas/legislação & jurisprudência , Órgãos Governamentais , Avaliação da Tecnologia Biomédica/métodos , Europa (Continente) , Humanos , Projetos Piloto
3.
Clin Pharmacol Ther ; 98(5): 534-41, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26080745

RESUMO

Conditional marketing authorization (CMA) in the European Union (EU) is an early access pathway for medicines that show promising therapeutic effects, but for which comprehensive data are not available. Using a mixed quantitative-qualitative research design, we evaluated how CMA has been used in marketing authorization of oncology medicines in the period 2006 to 2013. We show that compared to full marketing authorization, CMA is granted based on less comprehensive data. However, this is accompanied by significantly longer assessment times and less consensus among regulators about marketing authorization. Moreover, development time from first-in-human testing to marketing authorization did not differ between full marketing authorization and CMA, but was significantly longer for CMA compared to accelerated approved products in the United States (US). Results indicate that CMA is not used by companies as a prospectively planned pathway to obtain early access, but as a "rescue option" when submitted data are not strong enough to justify full marketing authorization.


Assuntos
Antineoplásicos/uso terapêutico , Aprovação de Drogas/métodos , União Europeia , Marketing/métodos , Estudos de Coortes , Aprovação de Drogas/legislação & jurisprudência , Europa (Continente) , Humanos , Marketing/legislação & jurisprudência
5.
Clin Pharmacol Ther ; 93(5): 433-42, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23549148

RESUMO

We analyzed the cost-effectiveness of all Periodic Safety Update Reports (PSURs) submitted for biologicals in Europe from 1995 to 2009 by comparing two regulatory scenarios: full regulation (PSUR reporting) and limited regulation (no PSUR reporting, but all other parts of the pharmacovigilance framework remain in place). During this period, PSUR reporting resulted in the detection of 2 out of a total of 24 urgent safety issues for biologicals: (i) distant spread of botulinum toxin and (ii) edema/fluid collection associated with off-label use of dibotermin-alfa. We used Markov-chain life tables to calculate costs and health effects of PSURs. The incremental cost-effectiveness ratio (ICER) of full regulation (PSUR reporting) vs. limited regulation (no PSUR reporting) for the base-case scenario was \[euro]342,110 per quality-adjusted life year (QALY) gained. It is possible to assess the cost-effectiveness of regulatory requirements using the same methods as those used in assessing the cost-effectiveness of medical interventions.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/economia , Produtos Biológicos/efeitos adversos , Legislação de Medicamentos , Farmacovigilância , Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Produtos Biológicos/uso terapêutico , Proteína Morfogenética Óssea 2/efeitos adversos , Proteína Morfogenética Óssea 2/uso terapêutico , Toxinas Botulínicas/efeitos adversos , Toxinas Botulínicas/uso terapêutico , Análise Custo-Benefício , Europa (Continente) , União Europeia , Humanos , Cadeias de Markov , Uso Off-Label , Anos de Vida Ajustados por Qualidade de Vida
6.
Acta Neurol Scand ; 127(5): 351-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23278859

RESUMO

OBJECTIVE: To assess the cost-effectiveness of endovascular treatment against intravenous thrombolysis (IVT) when varying assumptions concerning its effectiveness. METHODS: We developed a health economic model including a hypothetical population consisting of patients with ischemic stroke, admitted within 4.5 h from onset, without contraindications for IVT or intra-arterial treatment (IAT). A decision tree and life table were used to assess 6-month and lifetime costs (in Euros) and effects in quality-adjusted life years treatment with IVT alone, IAT alone, and IVT followed by IAT if the patient did not respond to treatment. Several analyses were performed to explore the impact of considerable uncertainty concerning the clinical effectiveness of endovascular treatment. RESULTS: Probabilistic sensitivity analysis demonstrated a 54% probability of positive incremental lifetime effectiveness of IVT-IAT vs IVT alone. Sensitivity analyses showed significant variation in outcomes and cost-effectiveness of the included treatment strategies at different model assumptions. CONCLUSIONS: Acceptable cost-effectiveness of IVT-IAT compared to IVT will only be possible if recanalization rates are sufficiently high (>50%), treatment costs of IVT-IAT do not increase, and complication rates remain similar to those reported in the few randomized studies published to date. Large randomized studies are needed to reduce the uncertainty concerning the effects of endovascular treatment.


Assuntos
Isquemia Encefálica/economia , Revascularização Cerebral/economia , Simulação por Computador , Procedimentos Endovasculares/economia , Fibrinolíticos/economia , Custos de Cuidados de Saúde , Modelos Econômicos , Terapia Trombolítica/economia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/reabilitação , Isquemia Encefálica/cirurgia , Revascularização Cerebral/métodos , Análise Custo-Benefício , Árvores de Decisões , Gerenciamento Clínico , Fibrinolíticos/administração & dosagem , Serviços de Assistência Domiciliar/economia , Custos Hospitalares , Humanos , Tábuas de Vida , Anos de Vida Ajustados por Qualidade de Vida , Tomografia Computadorizada por Raios X/economia , Resultado do Tratamento
7.
Clin Pharmacol Ther ; 91(2): 281-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22205197

RESUMO

We analyzed the cost-effectiveness of the International Conference on Harmonisation (ICH) E14 guideline that requires a thorough QT/QTc (TQT) study for all drugs under development. We compared two pharmacoeconomic scenarios: the health effects and costs resulting from implementing ICH E14 ("regulation" scenario) vs. not implementing ICH E14 ("no regulation" scenario). We used a dynamic population model to calculate the cost-effectiveness of ICH E14 for a prototype QT-prolonging antipsychotic drug entering the US and European markets. The incremental cost-effectiveness ratios of regulation vs. no regulation were ~€2.4 million per sudden cardiac death prevented and ~€187,000 per quality-adjusted life year (QALY) gained in users of antipsychotic drugs. The main driver of cost was the requirement for electrocardiogram (ECG) monitoring of users of QTc-prolonging drugs. Even when several of the assumptions in the model were varied, there were no results in favor of regulation. Our study shows that cost-effectiveness analysis of drug regulatory measures is feasible and should be considered before developing such measures.


Assuntos
Antipsicóticos/economia , Análise Custo-Benefício/estatística & dados numéricos , Controle de Medicamentos e Entorpecentes/economia , Eletrocardiografia/economia , Antipsicóticos/efeitos adversos , Humanos , Modelos Econômicos
9.
Eur J Clin Microbiol ; 5(6): 655-6, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3803377

RESUMO

A case is reported of a fifty-seven year old man with fever, who was admitted to hospital after a recent visit to Southeast Asia. Among the clinical findings prostatitis and broncho-pneumonia were noted. Within twenty-four hours irreversible fulminant sepsis developed although he was treated with cefotaxime, tobramycin and erythromycin. Post mortem Pseudomonas pseudomallei was cultured from blood and aspirate collected by bronchoscopy. It is important to consider melioidosis as a cause of septic illness in patients who have been visiting Southeast Asia.


Assuntos
Melioidose , Sepse , Humanos , Indonésia , Masculino , Pessoa de Meia-Idade , Países Baixos , Pseudomonas/isolamento & purificação , Tailândia , Viagem
10.
Semin Oncol ; 13(3 Suppl 3): 97-103, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3020707

RESUMO

Sixty patients with inoperable non-small-cell lung cancer (NSCLC) were entered into a phase II study that tested the combination of cisplatin (80 mg/m2, day, etoposide intravenously (IV) (100 mg, days 1 and etoposide orally (200 mg/m2, days 3 and 5). The regimen was repeated every 28 days for six courses, after which patients were allowed to receive additional treatment at the discretion of their physician. Overall objective response rate in 51 evaluable patients was 69% (95% confidence interval: range, 56% to 81%), with 16% sustaining complete remission (CR), 53% partial remission (PR), 17% stable disease (SD), and 14% progressive disease (PD). CR was pathologically confirmed by bronchoscopy and biopsy. One patient with a clinical PR underwent surgery and was shown to have a pathologic CR. Median survival of all evaluable patients was 52 weeks, greater than 75 weeks for CR patients, 52 weeks for PR patients, 42 weeks for SD patients, and 13 weeks for PD patients. Eleven patients (21.5%) developed CNS metastases, which resulted in the deaths of ten. Survival was significantly correlated with extent of disease, performance status, and albumin level, but not with histology or weight loss. Tumor response was significantly correlated only with histology (squamous-cell and large-cell undifferentiated carcinoma greater than adenocarcinoma). Side effects were nausea, vomiting, anorexia, alopecia, bone marrow suppression, and nephrotoxicity. One patient died from leukopenia and sepsis. Pharmacokinetic studies in ten patients showed the continuous presence of etoposide in plasma for six days at a level of at least 220 to 480 ng/mL. In order to investigate whether this very effective combination of cisplatin and etoposide can prolong survival in NSCLC, it will be tested as preoperative chemotherapy in a randomized trial in operable patients with T1N1 and T2N0-1 disease.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Administração Oral , Cisplatino/administração & dosagem , Avaliação de Medicamentos , Etoposídeo/administração & dosagem , Humanos , Prognóstico , Indução de Remissão
12.
J Neurol Sci ; 40(1): 39-51, 1979 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-762593

RESUMO

Deficiency of carnitine palmitoyltransferase II (CPT II), was found to be the cause of the syndrome of muscle pain and myoglobinuria following strenuous exercise in an otherwise healthy young man. During fasting, serum creatine kinase remained low and ketogenesis was normal. The clearance of a fat emulsion and the activity of extrahepatic lipoprotein lipase was lowered, while the hepatic lipoprotein lipase was normal. A skeletal muscle biopsy did not show abnormal lipid storage. CPT II was deficient in skeletal muscle and leucocytes, while CPT I activity was normal and exhibited normal kinetic properties. CPT I has a higher affinity for palmitoylcarnitine than CPT II, and is more inhibited at increasing palmitoylcarnitine concentrations. In erythrocytes only CPT I is present.


Assuntos
Aciltransferases/deficiência , Carnitina O-Palmitoiltransferase/deficiência , Isoenzimas/metabolismo , Leucócitos/enzimologia , Músculos/enzimologia , Adulto , Carnitina O-Palmitoiltransferase/metabolismo , Membrana Eritrocítica/enzimologia , Humanos , Lipase Lipoproteica/metabolismo , Fígado/enzimologia , Masculino , Microscopia Eletrônica , Músculos/ultraestrutura
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