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1.
J Magn Reson Imaging ; 57(6): 1676-1695, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36912262

RESUMO

Preoperative clinical MRI protocols for gliomas, brain tumors with dismal outcomes due to their infiltrative properties, still rely on conventional structural MRI, which does not deliver information on tumor genotype and is limited in the delineation of diffuse gliomas. The GliMR COST action wants to raise awareness about the state of the art of advanced MRI techniques in gliomas and their possible clinical translation. This review describes current methods, limits, and applications of advanced MRI for the preoperative assessment of glioma, summarizing the level of clinical validation of different techniques. In this second part, we review magnetic resonance spectroscopy (MRS), chemical exchange saturation transfer (CEST), susceptibility-weighted imaging (SWI), MRI-PET, MR elastography (MRE), and MR-based radiomics applications. The first part of this review addresses dynamic susceptibility contrast (DSC) and dynamic contrast-enhanced (DCE) MRI, arterial spin labeling (ASL), diffusion-weighted MRI, vessel imaging, and magnetic resonance fingerprinting (MRF). EVIDENCE LEVEL: 3. TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias Encefálicas , Glioma , Imageamento por Ressonância Magnética , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Meios de Contraste , Glioma/diagnóstico por imagem , Glioma/cirurgia , Glioma/patologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Período Pré-Operatório
2.
J Magn Reson Imaging ; 57(6): 1655-1675, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36866773

RESUMO

Preoperative clinical magnetic resonance imaging (MRI) protocols for gliomas, brain tumors with dismal outcomes due to their infiltrative properties, still rely on conventional structural MRI, which does not deliver information on tumor genotype and is limited in the delineation of diffuse gliomas. The GliMR COST action wants to raise awareness about the state of the art of advanced MRI techniques in gliomas and their possible clinical translation or lack thereof. This review describes current methods, limits, and applications of advanced MRI for the preoperative assessment of glioma, summarizing the level of clinical validation of different techniques. In this first part, we discuss dynamic susceptibility contrast and dynamic contrast-enhanced MRI, arterial spin labeling, diffusion-weighted MRI, vessel imaging, and magnetic resonance fingerprinting. The second part of this review addresses magnetic resonance spectroscopy, chemical exchange saturation transfer, susceptibility-weighted imaging, MRI-PET, MR elastography, and MR-based radiomics applications. Evidence Level: 3 Technical Efficacy: Stage 2.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Imageamento por Ressonância Magnética/métodos , Glioma/diagnóstico por imagem , Glioma/cirurgia , Glioma/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Espectroscopia de Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética
3.
AAPS PharmSciTech ; 19(3): 1274-1286, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29313262

RESUMO

Praziquantel (PZQ) is the recommended, effective, and safe treatment against all forms of schistosomiasis. Solid dispersions (SDs) in water-soluble polymers have been reported to increase solubility and bioavailability of poorly water-soluble drugs like PZQ, generally due to the amorphous form stabilization. In this work, poloxamer (PLX) 237 and poly(vinylpyrrolidone) (PVP) K30 were evaluated as potential carriers to revert PZQ crystallization. Binary and ternary SDs were prepared by the solvent evaporation method. PZQ solubility increased similarly with PLX either as binary physical mixtures or SDs. Such unpredicted data correlated well with crystalline PZQ and PLX as detected by solid-state NMR (ssNMR) and differential scanning calorimetry in those samples. Ternary PVP/PLX/PZQ SDs showed both ssNMR broad and narrow superimposed signals, thus revealing the presence of amorphous and crystalline PZQ, respectively, and exhibited the highest PZQ dissolution efficiency (up to 82% at 180 min). SDs with PVP provided a promising way to enhance solubility and dissolution rate of PZQ since PLX alone did not prevent recrystallization of amorphous PZQ. Based on ssNMR data, novel evidences on PLX structure and molecular dynamics were also obtained. As shown for the first time using ssNMR, propylene glycol and ethylene glycol constitute the PLX amorphous and crystalline components, respectively.


Assuntos
Anti-Helmínticos/química , Portadores de Fármacos/química , Poloxâmero/química , Povidona/química , Praziquantel/química , Anti-Helmínticos/administração & dosagem , Varredura Diferencial de Calorimetria , Cristalização , Praziquantel/administração & dosagem , Solubilidade
4.
Br J Clin Pharmacol ; 83(3): 540-553, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27763682

RESUMO

AIMS: To compare the levodopa/carbidopa (LC) and levodopa/benserazide (LB) pharmacokinetic profiles following repeated doses of opicapone (OPC) administered apart from levodopa. METHODS: Two randomized, double blind, sex-balanced, placebo-controlled studies in four groups of 12 or 18 healthy subjects each. In each group, enrolled subjects received a once-daily morning (5, 15 and 30 mg) or evening (5, 15 and 50 mg) administration of OPC or placebo for up to 28 days. On the morning of Day 11, 12 h after the OPC or placebo evening dose, or the morning of Day 21, 1 h after the OPC or placebo dose, a single dose of immediate-release 100/25 mg LC was administered. Similarly, on Day 18 morning, 12 h after the OPC or placebo evening dose, or Day 28 morning, 1 h after the OPC or placebo dose, a single dose of immediate-release 100/25 mg LB was administered. RESULTS: All OPC treatments, in relation to the placebo group, presented a higher extent of exposure (AUC) to levodopa following either LC or LB doses. A relevant but not dose-dependent increase in the levodopa AUC occurred with all OPC dose groups in relation to placebo. All active treatments significantly inhibited both peak (Emax ) and extent (AUEC) of the catechol-O-methyltransferase activity in relation to placebo. The tolerability profile was favourable. CONCLUSION: Opicapone, as once-daily oral evening regimen and/or 1 h apart from levodopa therapy, increases the bioavailability of levodopa associated with its pronounced, long-lasting and sustained catechol-O-methyltransferase inhibition. The tolerability profile was favourable and similar between OPC and placebo.


Assuntos
Benserazida/farmacocinética , Levodopa/farmacocinética , Oxidiazóis/farmacologia , Oxidiazóis/farmacocinética , Adulto , Antiparkinsonianos/farmacocinética , Benserazida/efeitos adversos , Benserazida/sangue , Benserazida/farmacologia , Disponibilidade Biológica , Carbidopa/efeitos adversos , Carbidopa/farmacologia , Inibidores de Catecol O-Metiltransferase/efeitos adversos , Inibidores de Catecol O-Metiltransferase/sangue , Inibidores de Catecol O-Metiltransferase/farmacocinética , Inibidores de Catecol O-Metiltransferase/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Levodopa/efeitos adversos , Levodopa/sangue , Levodopa/farmacologia , Masculino , Pessoa de Meia-Idade , Oxidiazóis/efeitos adversos , Oxidiazóis/sangue
5.
J Environ Sci (China) ; 53: 122-131, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28372736

RESUMO

In summer 2010, twenty eight (14 PM2.5 samples plus 14 samples PM2.5-10) smoke samples were collected during wildfires that occurred in central Portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse (PM2.5-10) and fine (PM2.5) smoke samples. The carbonaceous content (elemental and organic carbon) of particulate matter was analysed by a thermal-optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatography into three different classes of organic compounds (aliphatics, polycyclic aromatic hydrocarbons (PAHs) and carbonyl compounds). The organic speciation was performed by gas chromatography-mass spectrometry (GC-MS). Emissions were dominated by the fine particles, which represented around 92% of the PM10. A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon (OC/EC) ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone 6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between OC and both aliphatic and PAH compounds. Pyrogenic processes, thermal release of biogenic compounds and secondary processing accounted for 97% of the apportioned PM2.5 levels.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Incêndios , Hidrocarbonetos/análise , Material Particulado/análise , Aerossóis/análise , Hidrocarbonetos Policíclicos Aromáticos , Portugal , Estações do Ano
6.
Cephalalgia ; 36(14): 1370-1378, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26826092

RESUMO

BACKGROUND: Haemodialysis arteriovenous fistulas have common local and regional complications, but are rarely associated with neurological symptoms. CASE REPORT: A 43-year-old woman presented with short acute episodes of unilateral, non-throbbing, severe headache, vertigo and left lateropulsion. She had undergone renal transplantation and had a still-functioning left brachial arteriovenous fistula. No abnormality was detected on neurological examination or on brain parenchymal imaging. Colour Doppler ultrasonography showed a subclavian steal syndrome of the left vertebral artery and reversed flow in the left internal jugular vein. Ligation of the arteriovenous fistula had to be delayed as a result of renal graft dysfunction. Six months later she developed a headache attributed to intracranial hypertension. All symptoms subsided after ligation of the arteriovenous fistula. LITERATURE REVIEW: We identified 16 case reports of central neurological complications attributed to haemodialysis brachial fistulas. Headache descriptions were scarce and were not fully detailed. CONCLUSIONS: The case of our patient suggests that unilateral, episodic, non-throbbing, non-postural headache with transient neurological symptoms can be caused by combined arterial and venous flow abnormalities secondary to a high-flow arteriovenous brachial fistula. In this setting, this pattern of headache may precede overt signs of intracranial hypertension and may be used as a warning sign of cerebral venous congestion.


Assuntos
Fístula Arteriovenosa/complicações , Fístula Arteriovenosa/diagnóstico por imagem , Artéria Braquial/diagnóstico por imagem , Cefaleia/diagnóstico por imagem , Cefaleia/etiologia , Hemodinâmica/fisiologia , Veias Jugulares/diagnóstico por imagem , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Humanos , Ultrassonografia Doppler em Cores
7.
Eur J Public Health ; 26(5): 887-889, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27335325

RESUMO

The rate of invasive pneumococcal disease has markedly declined after the introduction of pneumococcal conjugated vaccines. In spite of the high effectiveness of this vaccine, there are some reports of vaccine failure and vaccine breakthroughs. Data on children with pneumococcal pneumonia in a European tertiary Hospital, from 2012 to 2014, were retrospectively collected before the implementation of pneumococcal conjugated vaccines in our country. We found four cases of pneumococcal serotype 3 vaccine failure and three cases of vaccine breakthroughs (two with serotype 3 and one with serotype 19A). All of these children were previously healthy.


Assuntos
Vacinas Pneumocócicas/uso terapêutico , Pneumonia Pneumocócica/prevenção & controle , Streptococcus pneumoniae/efeitos dos fármacos , Centros de Atenção Terciária/estatística & dados numéricos , Vacinas Conjugadas/uso terapêutico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Masculino , Pneumonia Pneumocócica/epidemiologia , Portugal/epidemiologia , Prevalência , Estudos Retrospectivos
8.
Epilepsia ; 56(2): 244-53, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25528898

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of adjunctive eslicarbazepine acetate (ESL) in patients with refractory partial-onset seizures. METHODS: This randomized, placebo-controlled, double-blind, parallel-group, phase III study was conducted at 173 centers in 19 countries, including the United States and Canada. Eligible patients were aged ≥16 years and had uncontrolled partial-onset seizures despite treatment with 1-2 antiepileptic drugs (AEDs). After an 8-week baseline period, patients were randomized to once-daily placebo (n = 226), ESL 800 mg (n = 216), or ESL 1,200 mg (n = 211). Following a 2-week titration period, patients received ESL 800 or 1,200 mg once-daily for 12 weeks. Seizure data were captured and documented using event-entry or daily entry diaries. RESULTS: Standardized seizure frequency (SSF) during the maintenance period (primary end point) was reduced with ESL 1,200 mg (p = 0.004), and there was a trend toward improvement with ESL 800 mg (p = 0.06), compared with placebo. When data for titration and maintenance periods were combined, ESL 800 mg (p = 0.001) and 1,200 mg (p < 0.001) both reduced SSF. There were no statistically significant interactions between treatment response and geographical region (p = 0.38) or diary version (p = 0.76). Responder rate (≥50% reduction in SSF) was significantly higher with ESL 1,200 mg (42.6%, p < 0.001) but not ESL 800 mg (30.5%, p = 0.07) than placebo (23.1%). Incidence of treatment-emergent adverse events (TEAEs) and TEAEs leading to discontinuation increased with ESL dose. The most common TEAEs were dizziness, somnolence, nausea, headache, and diplopia. SIGNIFICANCE: Adjunctive ESL 1,200 mg once-daily was more efficacious than placebo in adult patients with refractory partial-onset seizures. The once-daily 800 mg dose showed a marginal effect on SSF, but did not reach statistical significance. Both doses were well tolerated. Efficacy assessment was not affected by diary format used.


Assuntos
Anticonvulsivantes/uso terapêutico , Dibenzazepinas/uso terapêutico , Convulsões/tratamento farmacológico , Adolescente , Adulto , Idoso , Dibenzazepinas/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
9.
Mol Pharm ; 11(3): 727-37, 2014 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-24499472

RESUMO

Statins have been widely used as cholesterol-lowering agents. However, low aqueous solubility of crystalline statins and, consequently, reduced biovailability require seeking for alternative forms and formulations to ensure an accurate therapeutic window. The objective of the present study was to evaluate the stability of amorphous simvastatin by probing molecular dynamics using two nondestructive techniques: solid-state NMR and dielectric relaxation spectroscopy. Glassy simvastatin was obtained by the melt quench technique. (13)C cross-polarization/magic-angle-spinning (CP/MAS) NMR spectra and (1)H MAS NMR spectra were obtained from 293 K up to 333 K (Tg ≈ 302 K). The (13)C spin-lattice relaxation times in the rotating frame, T1ρ, were measured as a function of temperature, and the correlation time and activation energy data obtained for local motions in different frequency scales revealed strong dynamic heterogeneity, which appears to be essential for the stability of the amorphous form of simvastatin. In addition, the (1)H MAS measurements presented evidence for mobility of the hydrogen atoms in hydroxyl groups which was assigned to noncooperative secondary relaxations. The complex dielectric permittivity of simvastatin was monitored in isochronal mode at five frequencies (from 0.1 to 1000 kHz), by carrying out a heating/cooling cycle allowing to obtain simvastatin in the supercooled and glassy states. The results showed that no dipolar moment was lost due to immobilization, thus confirming that no crystallization had taken place. Complementarily, the present study focused on the thermal stability of simvastatin using thermogravimetric analysis while the thermal events were followed up by differential scanning calorimetry and dielectric relaxation spectroscopy. Overall, the results confirm that the simvastatin in the glass form reveals a potential use in the solid phase formulation on the pharmaceutical industry.


Assuntos
Espectroscopia Dielétrica , Inibidores de Hidroximetilglutaril-CoA Redutases/química , Espectroscopia de Ressonância Magnética , Sinvastatina/química , Varredura Diferencial de Calorimetria , Cristalização , Estabilidade de Medicamentos , Humanos , Simulação de Dinâmica Molecular , Termodinâmica , Termogravimetria
10.
Br J Clin Pharmacol ; 77(6): 1017-26, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24168152

RESUMO

AIMS: Etamicastat is a reversible dopamine-ß-hydroxylase inhibitor that decreases noradrenaline levels in sympathetically innervated tissues and slows down sympathetic nervous system drive. In this study, the disposition, metabolism and excretion of etamicastat were evaluated following [(14)C]-etamicastat dosing. METHODS: Healthy Caucasian males (n = 4) were enrolled in this single-dose, open-label study. Subjects were administered 600 mg of unlabelled etamicastat and 98 µCi weighing 0.623 mg [(14)C]-etamicastat. Blood samples, urine and faeces were collected to characterize the disposition, excretion and metabolites of etamicastat. RESULTS: Eleven days after administration, 94.0% of the administered radioactivity had been excreted; 33.3 and 58.5% of the administered dose was found in the faeces and urine, respectively. Renal excretion of unchanged etamicastat and its N-acetylated metabolite (BIA 5-961) accounted for 20.0 and 10.7% of the dose, respectively. Etamicastat and BIA 5-961 accounted for most of the circulating radioactivity, with a BIA 5-961/etamicastat ratio that was highly variable both for the maximal plasma concentration (19.68-226.28%) and for the area under the plasma concentration-time curve from time zero to the last sampling time at which the concentration was above the limit of quantification (15.82- 281.71%). Alongside N-acetylation, metabolism of etamicastat also occurs through oxidative deamination of the aminoethyl moiety, alkyl oxidation, desulfation and glucuronidation. CONCLUSIONS: Etamicastat is rapidly absorbed, primarily excreted via urine, and its biotransformation occurs mainly via N-acetylation (N-acetyltransferase type 2), although glucuronidation, oxidation, oxidative deamination and desulfation also take place.


Assuntos
Benzopiranos/metabolismo , Dopamina beta-Hidroxilase/antagonistas & inibidores , Inibidores Enzimáticos/metabolismo , Imidazóis/metabolismo , Adulto , Arilamina N-Acetiltransferase/genética , Radioisótopos de Carbono , Fezes/química , Genótipo , Humanos , Isoenzimas/genética , Masculino , Pessoa de Meia-Idade
11.
Pharm Res ; 31(11): 3136-49, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24842662

RESUMO

PURPOSE: To prepare and thoroughly characterize a new polymorph of the broad-spectrum antibiotic minocycline from its hydrochloride dehydrate salts. METHODS: The new minocycline hydrochloride polymorph was prepared by means of the antisolvent effect caused by carbon dioxide. Minocycline recrystallized as a red crystalline hydrochloride salt, starting from solutions or suspensions containing CO2 and ethanol under defined conditions of temperature, pressure and composition. RESULTS: This novel polymorph (ß-minocycline) revealed characteristic PXRD and FTIR patterns and a high melting point (of 247 ºC) compared to the initial minocycline hydrochloride hydrates (α-minocycline). Upon dissolution the new polymorph showed full anti-microbial activity. Solid-state NMR and DSC studies evidenced the higher chemical stability and crystalline homogeneity of ß-minocycline compared to the commercial chlorohydrate powders. Molecular structures of both minocyclines present relevant differences as shown by multinuclear solid-state NMR. CONCLUSIONS: This work describes a new crystalline structure of minocycline and evidences the ability of ethanol-CO2 system in removing water molecules from the crystalline structure of this API, at modest pressure, temperature and relatively short time (2 h), while controlling the crystal habit. This process has therefore the potential to become a consistent alternative towards the control of the solid form of APIs.


Assuntos
Dióxido de Carbono/química , Minociclina/química , Polímeros/química , Anti-Infecciosos/química , Cristalização/métodos , Etanol/química , Pós/química , Solubilidade , Soluções/química , Suspensões/química , Temperatura , Água/química
12.
Eur J Clin Pharmacol ; 70(3): 279-86, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24271646

RESUMO

PURPOSE: Opicapone (OPC) is a novel catechol-O-methyltransferase (COMT) inhibitor to be used as adjunctive therapy in levodopa-treated patients with Parkinson's disease. The purpose of this study was to evaluate the effect of moderate liver impairment on the pharmacokinetics (PK) and pharmacodynamics (PD; effect on COMT activity) of OPC. METHODS: An open-label, parallel-group study in patients (n = 8) with moderate liver impairment (Child-Pugh category B, score of 7 to 9) and matched healthy subjects (n = 8, control) with normal liver function. All subjects received a single 50-mg oral dose of OPC, with plasma and urine concentrations of opicapone and its metabolites measured up to 72 h post-dose, including soluble COMT (S-COMT) activity. A one-way analysis of variance (ANOVA) was used to compare the main PK and PD parameters between groups. Point estimates (PE) of geometric mean ratios (GMR) and corresponding 90 % confidence intervals (90%CI) for the ratio hepatic/control subjects of each parameter were calculated and compared with the reference interval (80-125 %). RESULTS: Exposure to opicapone (AUC and Cmax) increased significantly in patients with moderate hepatic impairment (PE [90%CI]: AUC0-∞, 184 % [135-250 %]; Cmax, 189 % [144-249 %]). Although apparent total clearance (CL/F) of opicapone was decreased by ∼35 %, similar elimination half-life and unbound/bound fractions of opicapone were observed between the two groups. Both rate and extent of exposure to BIA 9-1103 were higher in the hepatically impaired group, but not statistically significant compared with the control group. Similar to the parent (opicapone), the observed increase in exposure to BIA 9-1106 was statistically significant in the hepatically impaired group over the control group. BIA 9-1106 was the only metabolite detected in urine and its urine PK parameters were in accordance with plasma data. Maximum S-COMT inhibition (Emax) occurred earlier for the hepatically impaired group with values of 100 % and 91.2 % for the hepatically impaired and control groups respectively. Both Emax and AUEC for the hepatically impaired group reached statistical significance over the control group. OPC was well tolerated in both hepatically impaired and control groups. CONCLUSION: The bioavailability of an orally administered single dose of 50 mg OPC was significantly higher in patients with moderate chronic hepatic impairment, perhaps by a reduced first-pass effect. As the tolerability profile of OPC was favourable under the conditions of this study and its exposure is completely purged from systemic circulation before the subsequent dose administration, no OPC dose adjustment is needed in patients with mild to moderate chronic hepatic impairment. However, as OPC is under clinical development for use as adjunctive therapy in levodopa-treated patients with Parkinson's disease, an adjustment of levodopa and/or OPC regimens in patients should be carefully considered based on a potentially enhanced levodopa dopaminergic response and the associated tolerability.


Assuntos
Antiparkinsonianos/farmacocinética , Inibidores de Catecol O-Metiltransferase , Hepatopatias/fisiopatologia , Oxidiazóis/farmacocinética , Administração Oral , Adulto , Análise de Variância , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/farmacologia , Área Sob a Curva , Disponibilidade Biológica , Estudos de Casos e Controles , Feminino , Meia-Vida , Humanos , Masculino , Pessoa de Meia-Idade , Oxidiazóis/efeitos adversos , Oxidiazóis/farmacologia
13.
Eur J Clin Pharmacol ; 70(9): 1059-71, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24925090

RESUMO

BACKGROUND AND OBJECTIVES: Opicapone is a novel third generation catechol-O-methyltransferase (COMT) inhibitor. The purpose of this study was to compare the levodopa pharmacokinetic profile throughout a day driven by the COMT inhibition either following repeated doses of opicapone or concomitant administration with entacapone. METHODS: A randomized, double-blind, gender-balanced, parallel-group study was performed in 4 groups of 20 healthy subjects each. Four subjects in each group received placebo during the entire study. Sixteen subjects in one group received placebo once daily for 11 days and on day 12, 200 mg entacapone concomitantly with each levodopa/carbidopa dose (three times separated by a 5-h interval). Sixteen subjects in each of the remaining three groups received respectively 25, 50, and 75 mg opicapone once daily for 11 days and on day 12, placebo concomitantly with each levodopa/carbidopa dose. RESULTS: Levodopa minimum plasma concentration (Cmin) for each levodopa/carbidopa dose and for the mean of all levodopa/carbidopa doses increased substantially with all active treatments (entacapone and opicapone) when compared to the control group (placebo), with values ranging from 1.7-fold (200 mg entacapone) to 3.3-fold (75 mg opicapone). No statistical difference was found for levodopa peak of systemic exposure (as assessed by maximum observed plasma concentration (Cmax)) between all active treatments and placebo. A significant increase in the levodopa extent of systemic exposure (as assessed by concentration-time curve (AUC)) occurred with all opicapone treatments in relation to placebo. No statistical difference was found for levodopa AUC when entacapone was compared to placebo. When compared to entacapone, both 50 and 75 mg opicapone presented a significant increase for the levodopa AUC. All active treatments significantly inhibited both peak (as assessed by Emax) and extent (as assessed by effect-time curve (AUEC)) of the COMT activity in relation to placebo. When compared to entacapone, all opicapone treatments significantly decreased the extent (AUEC) of the COMT activity due to a long-lasting and sustained effect. The tolerability profile was favorable for all active treatments. CONCLUSION: Opicapone, a novel third generation COMT inhibitor, when compared to entacapone, provides a superior response upon the bioavailability of levodopa associated to more pronounced, long-lasting, and sustained COMT inhibition. The tolerability profile was favorable. On the basis of the results presented in this study and along with the earlier pharmacology studies, it is anticipated that opicapone adjunct therapy at the dosages of 25 and 50 mg will provide an enhancement in levodopa availability that will translate into clinical benefit for Parkinson's disease patients.


Assuntos
Antiparkinsonianos/farmacocinética , Inibidores de Catecol O-Metiltransferase/farmacologia , Catecóis/farmacologia , Levodopa/farmacocinética , Nitrilas/farmacologia , Oxidiazóis/farmacologia , Adulto , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/sangue , Antiparkinsonianos/farmacologia , Área Sob a Curva , Catecol O-Metiltransferase/metabolismo , Inibidores de Catecol O-Metiltransferase/efeitos adversos , Catecóis/efeitos adversos , Método Duplo-Cego , Esquema de Medicação , Interações Medicamentosas , Feminino , Humanos , Levodopa/administração & dosagem , Levodopa/efeitos adversos , Levodopa/sangue , Masculino , Pessoa de Meia-Idade , Nitrilas/efeitos adversos , Oxidiazóis/efeitos adversos , Adulto Jovem
14.
Sci Total Environ ; 918: 170598, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38340837

RESUMO

Indoor air quality is crucial for human health due to the significant time people spend at home, and it is mainly affected by internal sources such as solid fuel combustion for heating. This study investigated the indoor air quality and health implications associated with residential coal burning covering gaseous pollutants (CO, CO2 and total volatile organic compounds), particulate matter, and toxicity. The PM10 chemical composition was obtained by ICP-MS/OES (elements), ion chromatography (water-soluble ions) and thermal-optical analysis (organic and elemental carbon). During coal combustion, PM10 levels were higher (up to 8.8 times) than background levels and the indoor-to-outdoor ratios were, on average, greater than unity, confirming the existence of a significant indoor source. The chemical characterisation of PM10 revealed increased concentrations of organic carbon and elemental carbon during coal combustion as well as arsenic, cadmium and lead. Carcinogenic risks associated with exposure to arsenic exceeded safety thresholds. Indoor air quality fluctuated during the study, with varying toxicity levels assessed using the Aliivibrio fischeri bioluminescence inhibition assay. These findings underscore the importance of mitigating indoor air pollution associated with coal burning and highlight the potential health risks from long-term exposure. Effective interventions are needed to improve indoor air quality and reduce health risks in coal-burning households.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Arsênio , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Arsênio/análise , Carbono/análise , Carvão Mineral/análise , Monitoramento Ambiental , Material Particulado/análise
15.
Epilepsia ; 54(1): 108-16, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22812691

RESUMO

PURPOSE: To evaluate the pharmacokinetics and tolerability of once-daily eslicarbazepine acetate (ESL) and twice-daily oxcarbazepine (OXC) and their metabolites in cerebrospinal fluid (CSF) and plasma following repeated oral administration. METHODS: Single-center, open-label, randomized, parallel-group study in healthy volunteers. Volunteers in ESL group (n = 7) received 600 mg on days 1-3 and 1,200 mg on days 4-9, once daily. Volunteers in the OXC group (n = 7) received 300 mg on days 1-3 and 600 mg on days 4-9, twice daily. Plasma and CSF sampling was performed following the last dose. KEY FINDINGS: Eslicarbazepine was the major drug entity in plasma and CSF, accounting for, respectively, 93.84% and 91.96% of total exposure in the ESL group and 78.06% and 76.42% in the OXC group. The extent of exposure to drug entities R-licarbazepine and oxcarbazepine was approximately four-fold higher with OXC as compared with ESL. There was relatively little fluctuation from peak-to-trough (ratio) in the CSF for both eslicarbazepine (ESL = 1.5; OXC = 1.2) and R-licarbazepine (ESL = 1.2; OXC = 1.2). In contrast, oxcarbazepine showed larger differences between peak and trough (ESL = 3.1; OXC = 6.4). A total of 84 and 24 treatment-emergent adverse events (TEAEs) were reported with OXC and ESL, respectively. SIGNIFICANCE: In comparison to OXC, administration of ESL resulted in more eslicarbazepine, less R-licarbazepine, and less oxcarbazepine in plasma and CSF, which may correlate with the tolerability profile reported with ESL. The smaller peak-to-trough fluctuation of eslicarbazepine in CSF (a measure of sustained delivery to the brain) than in plasma supports once-daily dosing of ESL.


Assuntos
Anticonvulsivantes/farmacocinética , Carbamazepina/análogos & derivados , Dibenzazepinas/farmacocinética , Administração Oral , Adulto , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/sangue , Anticonvulsivantes/líquido cefalorraquidiano , Carbamazepina/administração & dosagem , Carbamazepina/sangue , Carbamazepina/líquido cefalorraquidiano , Carbamazepina/farmacocinética , Dibenzazepinas/administração & dosagem , Dibenzazepinas/sangue , Dibenzazepinas/líquido cefalorraquidiano , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Epilepsia ; 54(8): 1453-61, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23758485

RESUMO

PURPOSE: Investigate the pharmacokinetics of once-daily (QD; 900 mg) and twice-daily (BID; 450 mg) regimens of eslicarbazepine acetate (ESL) and BID (450 mg) regimen of oxcarbazepine (OXC) at steady state in healthy volunteers. METHODS: Single-center, open-label, randomized, three-way (n = 12) crossover studies in healthy volunteers. KEY FINDINGS: Mean eslicarbazepine Cmax,ss (in µm) following ESL QD (87.3) was 33.3% higher (p < 0.05) compared to ESL BID (65.5) and 82.1% higher (p < 0.05) compared to OXC BID (48.0). The mean area under the curve (AUC)ss,0-τ (in µmol h/L) following the last dose of an 8-day repeated dosing was 1156.3, 1117.6, and 968.4 for ESL QD, ESL BID, and OXC BID, respectively. The ratio eslicarbazepine plasma exposure (µmol h/L) to ESL daily-dose (µmol) was 0.381 (1156.3:3037.3), 0.368 (1117.6:3037.3), and 0.271 (968.4:3567.6) for ESL-QD, ESL-BID, and OXC-BID, respectively, which translates into a 40.6% increase in the ability of ESL-QD compared to OXC-BID to deliver into the plasma their major active entity eslicarbazepine. The extent of plasma exposure to ESL minor metabolites: (R)-licarbazepine and oxcarbazepine after ESL-QD was 71.5% and 61.1% lower, respectively, than after OXC-BID. Twenty, 24 and 38 treatment emergent adverse events were reported with ESL-QD, ESL-BID, and OXC-BID, respectively. SIGNIFICANCE: ESL-QD resulted in 33.3% higher peak plasma concentration (Cmax,ss ) of eslicarbazepine and similar extent of plasma exposure (AUCss,0-τ ) when compared to ESL-BID, which may contribute to the efficacy profile reported with once-daily ESL. In comparison to OXC-BID, administration of ESL-QD resulted in 40.6% increase in the delivery of eslicarbazepine into the plasma as well as a significantly lower systemic exposure to (R)-licarbazepine and oxcarbazepine.


Assuntos
Anticonvulsivantes/farmacocinética , Carbamazepina/análogos & derivados , Dibenzazepinas/farmacocinética , Adulto , Anticonvulsivantes/sangue , Anticonvulsivantes/química , Anticonvulsivantes/urina , Área Sob a Curva , Carbamazepina/sangue , Carbamazepina/química , Carbamazepina/farmacocinética , Carbamazepina/urina , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Dibenzazepinas/sangue , Dibenzazepinas/química , Dibenzazepinas/urina , Relação Dose-Resposta a Droga , Eletrocardiografia , Eletroquímica , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Oxcarbazepina , Fatores de Tempo
17.
Epilepsia ; 54(1): 98-107, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22882018

RESUMO

PURPOSE: To evaluate the efficacy and safety profile of eslicarbazepine acetate (ESL) added to stable antiepileptic therapy in adults with partial-onset seizures. METHODS: Data from 1,049 patients enrolled from 125 centers, in 23 countries, in three phase III double-blind, randomized, placebo-controlled studies were pooled and analyzed. Following a 2-week titration period, ESL was administered at 400 mg, 800 mg, and 1,200 mg once-daily doses for 12 weeks. KEY FINDINGS: Seizure frequency was significantly reduced with ESL 800 mg (p < 0.0001) and 1,200 mg (p < 0.0001) compared to placebo. Median relative reduction in seizure frequency was, respectively, 35% and 39% (placebo 15%) and responder rate was 36% and 44% (placebo 22%). ESL was more efficacious than placebo regardless of gender, geographic region, epilepsy duration, age at time of diagnosis, seizure type, and number and type of concomitant antiepileptic drugs (AEDs). Incidence of adverse events (AEs) and AEs leading to discontinuation were dose dependent. AEs occurred mainly during the first weeks of treatment, with no difference between groups after 6 weeks. Most common AEs (>10% patients) were dizziness, somnolence, and headache. The incidence of AEs in ESL groups compared to placebo was generally consistent among different subpopulations. SIGNIFICANCE: Once-daily ESL 800 mg and 1,200 mg showed consistent results across all efficacy and safety end points. Results were independent of study population characteristics and type and number of concomitant AEDs.


Assuntos
Anticonvulsivantes/uso terapêutico , Dibenzazepinas/uso terapêutico , Epilepsias Parciais/tratamento farmacológico , Adulto , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/efeitos adversos , Dibenzazepinas/administração & dosagem , Dibenzazepinas/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino
18.
Br J Clin Pharmacol ; 76(5): 763-75, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23336248

RESUMO

AIMS: The aim of this study was to assess the tolerability, pharmacokinetics and inhibitory effect on erythrocyte soluble catechol-O-methyltransferase (S-COMT) activity following repeated doses of opicapone. METHODS: This randomized, placebo-controlled, double-blind study enrolled healthy male subjects who received either once daily placebo or opicapone 5, 10, 20 or 30 mg for 8 days. RESULTS: Opicapone was well tolerated. Its systemic exposure increased in an approximately dose-proportional manner with an apparent terminal half-life of 1.0 to 1.4 h. Sulphation was the main metabolic pathway. Opicapone metabolites recovered in urine accounted for less than 3% of the amount of opicapone administered suggesting that bile is likely the main route of excretion. Maximum S-COMT inhibition (Emax ) ranged from 69.9% to 98.0% following the last dose of opicapone. The opicapone-induced S-COMT inhibition showed a half-life in excess of 100 h, which was dose-independent and much longer than plasma drug exposure. Such a half-life translates into a putative underlying rate constant that is comparable with the estimated dissociation rate constant of the COMT-opicapone complex. CONCLUSION: Despite its short elimination half-life, opicapone markedly and sustainably inhibited erythrocyte S-COMT activity making it suitable for a once daily regimen.


Assuntos
Antiparkinsonianos/administração & dosagem , Inibidores de Catecol O-Metiltransferase , Inibidores Enzimáticos/administração & dosagem , Oxidiazóis/administração & dosagem , Adulto , Antiparkinsonianos/farmacocinética , Antiparkinsonianos/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Meia-Vida , Humanos , Masculino , Pessoa de Meia-Idade , Oxidiazóis/farmacocinética , Oxidiazóis/farmacologia , Adulto Jovem
19.
Sci Total Environ ; 778: 146090, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34030360

RESUMO

The aim of this study was a detailed chemical characterisation of the particles released during the preparation of popular Portuguese dishes. PM2.5 samples were collected from the exhaust stacks on the roofs of a university canteen, a charcoal-grilled chicken restaurant and a wood-oven roasted piglet restaurant. The speciation of organic compounds was carried out by gas chromatography-mass spectrometry. The canteen was responsible for the lowest emissions of PM2.5, while emissions from the roasted piglet restaurant were the highest. Naphthalene was quantified as the most abundant aromatic compound in particle emissions from the canteen, while phenanthrene, fluoranthene, pyrene and chrysene were the dominant polycyclic aromatic hydrocarbons in samples from the other establishments. Benzo[a]pyrene equivalent concentrations obtained for the charcoal-grilled chicken and piglet restaurant indicate a dangerous carcinogenic potential to human health. Cholesterol was the prevalent sterol. Its highest values were obtained in particles from the charcoal-grilled chicken restaurant (621 ± 233 µg g-1 PM2.5). Oleic and palmitoleic were the unsaturated fatty acids identified at highest concentrations (from trace levels to 34.4 and to 6.89 mg g-1 PM2.5, respectively). Resin acids, such as dehydroabietic and abietic, were detected in all samples from the wood-oven roasted piglet restaurant. Nicotinamide was the amide detected at highest amount in emissions from the university canteen during the preparation of stews (7.67 mg g-1 PM2.5). Levoglucosan and its isomers were identified in all samples from the roasted piglet restaurant, but only the first monosaccharide anhydride was present in emissions from the university canteen and the charcoal-grilled chicken restaurant. Additionally, emission rates were estimated for the most representative compounds, taking into account the specific activity of each restaurant.

20.
Sci Total Environ ; 754: 142045, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916490

RESUMO

A one-year aerosol sampling campaign, between 2016 and 2017, was conducted in a suburban area of León city, Spain. An association between the Positive Matrix Factorization (PMF) results and air masses through circulation weather types was carried out, through the construction of linear models from the PM10 concentrations and its chemical composition. The aerosol sources, identified by PMF six-factor solution, were: traffic (29%), aged sea salt (26%), secondary aerosols (16%), dust (13%), marine aerosol (7%) and biomass burning (3%). Traffic and secondary factors showed the highest PM10 contribution in the hybrid cyclonic types with wind component from the first and second quadrant. Anticyclonic types with wind component from the first quadrant exhibited high values of secondary, aged sea salt and dust factors. The highest contributions of the dust factor were also associated with northerly types. The linear models built for estimating the source apportionment of PM10, from aerosol chemical composition and geostrophic flow, showed positive coefficients for: westerly flows (WF) in marine factor, southerly flows (SF) in secondary and traffic factors, and shear southerly vorticities (ZS) in dust factor. Negative dependences were observed for ZS in aged sea salt factor and for SF in dust factor. The PM10 mass concentration calculated by the linear models and by the PMF model were strongly correlated. This can be very useful to determine the contribution of a specific source to PM10 in León, only by knowing some meteorological and chemical variables.

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