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1.
Molecules ; 24(4)2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30813299

RESUMO

The aim of this study was to assess the effect of temperature, solvent (hydroethanolic mixtures) and pH on the recovery of individual phenolic compounds from "horchata" by-products. These parameters were optimized by response surface methodology and triple-TOF-LC-MS-MS was selected as the analytical tool to identify and quantify the individual compounds. The optimum extraction conditions were 50% ethanol, 35 °C and pH 2.5, which resulted in values of 222.6 mg gallic acid equivalents (GAE)/100 g dry matter and 1948.1 µM trolox equivalent (TE)/g of dry matter for total phenolic content (TPC) and trolox equivalent antioxidant capacity (TEAC), respectively. The extraction of phenolic compounds by the conventional solvent method with agitation was influenced by temperature (p = 0.0073), and more strongly, by the content of ethanol in the extraction solution (p = 0.0007) while the pH did not show a great impact (p = 0.7961). On the other hand, the extraction of phenolic acids was affected by temperature (p = 0.0003) and by ethanol amount (p < 0.0001) but not by the pH values (p = 0.53). In addition, the percentage of ethanol influenced notably the extraction of both 4-vinylphenol (p = 0.0002) and the hydroxycinnamic acids (p = 0.0039). Finally, the main individual phenolic extracted with hydroethanolic mixtures was 4-vinylphenol (303.3 µg/kg DW) followed by spinacetin3-O-glucosyl-(1→6)-glucoside (86.2 µg/kg DW) and sinensetin (77.8 µg/kg DW).


Assuntos
Antioxidantes/análise , Cyperus/química , Fenóis/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/isolamento & purificação , Flavonoides/isolamento & purificação , Concentração de Íons de Hidrogênio , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/química , Solventes , Espectrometria de Massas em Tandem , Temperatura
2.
Cephalalgia ; 38(8): 1493-1497, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29020806

RESUMO

Background Transcranial static magnetic field stimulation (tSMS) reduces cortical excitability in humans. Methods The objective of this study was to determine whether tSMS over the occipital cortex is effective in reducing experimental photophobia. In a sham-controlled double-blind crossover study, tSMS (or sham) was applied for 10 minutes with a cylindrical magnet on the occiput of 20 healthy subjects. We assessed subjective discomfort induced by low-intensity and high-intensity visual stimuli presented in a dark room before, during and after tSMS (or sham). Results Compared to sham, tSMS significantly reduced the discomfort induced by high-intensity light stimuli. Conclusions The visual cortex may contribute to visual discomfort in experimental photophobia, providing a rationale for investigating tSMS as a possible treatment for photophobia in migraine.


Assuntos
Fotofobia/terapia , Estimulação Magnética Transcraniana/métodos , Córtex Visual/fisiologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
Br J Clin Pharmacol ; 84(1): 142-152, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28888218

RESUMO

AIMS: Dual-urate-lowering therapy (ULT) with xanthine oxidase inhibitor and uricosuric medications is a treatment option for severe gout. Uricosuric agents can cause hyperuricosuria, a risk factor for nephrolithiasis and acute uric acid nephropathy. The aims of the present study were to simulate the relationship between suboptimal drug adherence and efficacy, and to quantify the risk of hyperuricosuria in gout patients receiving mono- and dual-ULTs. METHODS: The impact of poor medication adherence was studied using two-compartment pharmacokinetic (PK) models based on published evidence, and a semi-mechanistic four-compartment pharmacodynamic (PD) model. The PKPD model was used to simulate mono and dual-ULT in gout patients with either under-excretion (lowered clearance) or overproduction of uric acid, with suboptimal adherence modelled as either a single drug holiday of increasing duration or doses taken at random. RESULTS: Simulation results showed a surge in urinary uric acid occurring when dosing is restarted following missed doses. For under-excreters taking a 20-day drug holiday, the addition of 200 mg (or 400 mg) lesinurad to 80 mg febuxostat increased the percentage of patients experiencing hyperuricosuria from 0% to 1.4% (or 3.1%). In overproducers, restarting ULTs following drug holidays of more than 5 days leads to over 60% of patients experiencing hyperuricosuria. CONCLUSIONS: Suboptimal medication adherence may compromise the safety and efficacy of mono- and dual-ULTs, especially in patients with gout resulting from an overproduction of uric acid. Clinicians and pharmacists should consider counselling patients with respect to the risks associated with partial adherence, and offer interventions to improve adherence or tailor treatments, where appropriate.


Assuntos
Supressores da Gota/farmacologia , Gota/tratamento farmacológico , Adesão à Medicação , Modelos Biológicos , Ácido Úrico/sangue , Simulação por Computador , Quimioterapia Combinada , Febuxostat/farmacologia , Febuxostat/uso terapêutico , Gota/sangue , Supressores da Gota/uso terapêutico , Humanos , Masculino , Medição de Risco/métodos , Tioglicolatos/farmacologia , Tioglicolatos/uso terapêutico , Resultado do Tratamento , Triazóis/farmacologia , Triazóis/uso terapêutico , Xantina Oxidase/antagonistas & inibidores
4.
Value Health ; 21(12): 1373-1381, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30502780

RESUMO

BACKGROUND: Dual urate-lowering therapy (ULT) with lesinurad in combination with either allopurinol or febuxostat is an option for patients with gout unsuccessfully treated on either monotherapy. Treatment failure is often a result of poor medication adherence. Imperfect adherence in clinical trials may lead to biased estimates of treatment effect and confound the results of cost-effectiveness analyses. OBJECTIVES: To estimate the impact of varying medication adherence on the cost effectiveness of lesinurad dual therapy and estimate the value-based price of lesinurad at which the incremental cost-effectiveness ratio is equal to £20,000 per quality-adjusted life-year (QALY). METHODS: Treatment effect was simulated using published pharmacokinetic-pharmacodynamic models and scenarios representing adherence in clinical trials, routine practice, and perfect use. The subsequent cost and health impacts, over the lifetime of a patient cohort, were estimated using a bespoke pharmacoeconomic model. RESULTS: The base-case incremental cost-effectiveness ratios comparing lesinurad dual ULT with monotherapy ranged from £39,184 to £78,350/QALY gained using allopurinol and £31,901 to £124,212/QALY gained using febuxostat, depending on the assumed medication adherence. Results assuming perfect medication adherence imply a per-quarter value-based price of lesinurad of £45.14 when used in dual ULT compared with allopurinol alone and £57.75 compared with febuxostat alone, falling to £25.41 and £3.49, respectively, in simulations of worsening medication adherence. CONCLUSIONS: The estimated value-based prices of lesinurad only exceeded that which has been proposed in the United Kingdom when assuming both perfect drug adherence and the eradication of gout flares in sustained treatment responders.


Assuntos
Alopurinol/economia , Análise Custo-Benefício , Febuxostat/economia , Gota/economia , Adesão à Medicação , Tioglicolatos/economia , Triazóis/economia , Ácido Úrico/sangue , Alopurinol/uso terapêutico , Estudos de Coortes , Quimioterapia Combinada , Farmacoeconomia , Febuxostat/uso terapêutico , Gota/sangue , Gota/tratamento farmacológico , Supressores da Gota/economia , Supressores da Gota/uso terapêutico , Custos de Cuidados de Saúde , Humanos , Modelos Biológicos , Modelos Econômicos , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Tioglicolatos/uso terapêutico , Resultado do Tratamento , Triazóis/uso terapêutico , Reino Unido
5.
J Pharmacol Exp Ther ; 354(1): 55-64, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25948593

RESUMO

The current work integrates cell-cycle dynamics occurring in the bone marrow compartment as a key element in the structure of a semimechanistic pharmacokinetic/pharmacodynamic model for neutropenic effects, aiming to describe, with the same set of system- and drug-related parameters, longitudinal data of neutropenia gathered after the administration of the anticancer drug diflomotecan (9,10-difluoro-homocamptothecin) under different dosing schedules to patients (n = 111) with advanced solid tumors. To achieve such an objective, the general framework of the neutropenia models was expanded, including one additional physiologic process resembling cell cycle dynamics. The main assumptions of the proposed model are as follows: within the stem cell compartment, proliferative and quiescent cells coexist, and only cells in the proliferative condition are sensitive to drug effects and capable of following the maturation chain. Cell cycle dynamics were characterized by two new parameters, FProl (the fraction of proliferative [Prol] cells that enters into the maturation chain) and kcycle (first-order rate constant governing cell cycle dynamics within the stem cell compartment). Both model parameters were identifiable as indicated by the results from a bootstrap analysis, and their estimates were supported by date from the literature. The estimates of FProl and kcycle were 0.58 and 1.94 day(-1), respectively. The new model could properly describe the neutropenic effects of diflomotecan after very different dosing scenarios, and can be used to explore the potential impact of dosing schedule dependencies on neutropenia prediction.


Assuntos
Antineoplásicos/farmacologia , Camptotecina/análogos & derivados , Ciclo Celular , Modelos Biológicos , Neoplasias/tratamento farmacológico , Neutropenia/induzido quimicamente , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/patologia , Camptotecina/administração & dosagem , Camptotecina/farmacocinética , Camptotecina/farmacologia , Proliferação de Células , Ensaios Clínicos Fase I como Assunto , Esquema de Medicação , Humanos , Neoplasias/patologia , Neutropenia/sangue , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/patologia
6.
Br J Clin Pharmacol ; 77(3): 509-21, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24102758

RESUMO

AIMS: The aims of this study were to develop a population pharmacokinetic (PK) model of ampicillin and sulbactam, to identify patient characteristics influencing the PK, and to explore the relationship between dose regimen and degree of renal impairment with exposure and time above minimum inhibitory concentration (MIC). METHODS: This analysis was performed on PK data for ampicillin and sulbactam and MIC data from a clinical trial in Japanese patients with community acquired pneumonia. Simulations were performed to investigate the effects of different dosing intervals on exposure and time above MIC in various degrees of renal impairment. RESULTS: The plasma concentrations from 47 patients were adequately described by a two compartment model with simultaneous fit of ampicillin and sulbactam PK data, where creatinine clearance on clearance and body weight on volume in the peripheral compartment were identified as covariates for both drugs. Creatinine clearance contributed to reducing inter-individual variability of clearance by 16%. Mean clearance (inter-individual variability) for ampicillin and sulbactam was estimated to be 10.7 l h(-1) (14.8%) and 10.4 l h(-1) (15.2%), respectively. The time above MIC for each pathogen was generally > 50% of the treatment period. Simulations for exposure and time above MIC supported currently recommended dose adjustments. CONCLUSIONS: This study provided a PK model for ampicillin and sulbactam, the time above MICs for identified pathogens and associated simulation results. These findings provide useful information and augment evidence for the established dosage regimens in patients with various degrees of renal impairment.


Assuntos
Ampicilina/farmacocinética , Antibacterianos/farmacocinética , Infecções Comunitárias Adquiridas/tratamento farmacológico , Nefropatias/complicações , Rim/fisiopatologia , Pneumonia Bacteriana/tratamento farmacológico , Sulbactam/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Ampicilina/administração & dosagem , Ampicilina/sangue , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Infecções Comunitárias Adquiridas/sangue , Infecções Comunitárias Adquiridas/complicações , Infecções Comunitárias Adquiridas/microbiologia , Simulação por Computador , Esquema de Medicação , Combinação de Medicamentos , Cálculos da Dosagem de Medicamento , Feminino , Humanos , Infusões Intravenosas , Japão , Nefropatias/sangue , Nefropatias/fisiopatologia , Masculino , Taxa de Depuração Metabólica , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Modelos Biológicos , Pneumonia Bacteriana/sangue , Pneumonia Bacteriana/complicações , Pneumonia Bacteriana/microbiologia , Sulbactam/administração & dosagem , Sulbactam/sangue
7.
J Clin Med ; 12(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36675452

RESUMO

This study aimed to examine the presence of neuropsychological deficits and their relationships with clinical, pharmacological, and neuropsychiatric characteristics in chronic migraine (CM) patients assessed during a headache-free period. We enrolled 39 CM patients (mean age: 45.4 years; male/female ratio: 3/36) and 20 age-, sex-, and education-matched healthy controls (HCs, mean age: 45.5 years; male/female ratio: 2/18) in a case-control study. All CM patients underwent a full and extensive clinical, neuropsychiatric, and neuropsychological evaluation to evaluate cognitive domains, including sustained attention (SA), information processing speed (IPS), visuospatial episodic memory, working memory (WM), and verbal fluency (VF), as well as depressive and anxiety symptoms. CM patients exhibited higher scores than HCs for all clinical and neuropsychiatric measures, but no differences were found in personality characteristics. Although more than half of the CM patients (54%) showed mild-to-severe neuropsychological impairment (NI), with the most frequent impairments occurring in short- and long-term verbal episodic memory and inhibitory control (in approximately 90% of these patients), almost half of the patients (46%) showed no NI. Moreover, the severity of NI was positively associated with the number of pharmacological treatments received. Remarkably, disease-related symptom severity and headache-related disability explained global neuropsychological performance in CM patients. The presence of cognitive and neuropsychiatric dysfunction during the interictal phase occurred in more than half of CM patients, increasing migraine-related disability and possibly exerting a negative impact on health-related quality of life and treatment adherence.

8.
Front Aging Neurosci ; 15: 1258315, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869372

RESUMO

Background and objectives: Intermittent theta-burst stimulation (iTBS) is a patterned form of excitatory transcranial magnetic stimulation that has yielded encouraging results as an adjunctive therapeutic option to alleviate the emergence of clinical deficits in Parkinson's disease (PD) patients. Although it has been demonstrated that iTBS influences dopamine-dependent corticostriatal plasticity, little research has examined the neurobiological mechanisms underlying iTBS-induced clinical enhancement. Here, our primary goal is to verify whether iTBS bilaterally delivered over the primary motor cortex (M1) is effective as an add-on treatment at reducing scores for both motor functional impairment and nonmotor symptoms in PD. We hypothesize that these clinical improvements following bilateral M1-iTBS could be driven by endogenous dopamine release, which may rebalance cortical excitability and restore compensatory striatal volume changes, resulting in increased striato-cortico-cerebellar functional connectivity and positively impacting neuroglia and neuroplasticity. Methods: A total of 24 PD patients will be assessed in a randomized, double-blind, sham-controlled crossover study involving the application of iTBS over the bilateral M1 (M1 iTBS). Patients on medication will be randomly assigned to receive real iTBS or control (sham) stimulation and will undergo 5 consecutive sessions (5 days) of iTBS over the bilateral M1 separated by a 3-month washout period. Motor evaluation will be performed at different follow-up visits along with a comprehensive neurocognitive assessment; evaluation of M1 excitability; combined structural magnetic resonance imaging (MRI), resting-state electroencephalography and functional MRI; and serum biomarker quantification of neuroaxonal damage, astrocytic reactivity, and neural plasticity prior to and after iTBS. Discussion: The findings of this study will help to clarify the efficiency of M1 iTBS for the treatment of PD and further provide specific neurobiological insights into improvements in motor and nonmotor symptoms in these patients. This novel project aims to yield more detailed structural and functional brain evaluations than previous studies while using a noninvasive approach, with the potential to identify prognostic neuroprotective biomarkers and elucidate the structural and functional mechanisms of M1 iTBS-induced plasticity in the cortico-basal ganglia circuitry. Our approach may significantly optimize neuromodulation paradigms to ensure state-of-the-art and scalable rehabilitative treatment to alleviate motor and nonmotor symptoms of PD.

9.
Behav Neurol ; 2022: 1213393, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35586201

RESUMO

Background: Neuropsychiatric symptoms (NPS) are a common and potentially serious manifestation of Parkinson's disease (PD) but are frequently overlooked in favor of a focus on motor symptomatology. Here, we conducted a literature review of the prevalence and type of NPS experienced by PD patients with a clinically defined course of their illness. Methods: We identified reports of NPS in patients with PD and mean disease duration over 3 years. Three databases-PubMed, Scopus, and Dialnet-were searched for relevant literature published between 2010 and 2020. Predefined exclusion criteria were applied prior to a descriptive analysis of the literature base. Results: In all, 87 unique reports were identified and 30 met inclusion and exclusion criteria. These included 7142 patients with PD (male: 67.3%; mean age: 66.2 years; mean disease duration: 6.7 years). The most frequent NPS were mood disorders (apathy, depression, and anxiety), psychosis, and impulse control disorders (ICD). Treatment with dopamine agonists was identified as an important risk factor for ICD. Co-occurrence of NPS and cognitive dysfunction was also evidenced in a number of studies. Patients with more significant cognitive deficits and higher levels of NPS appeared to be of older age with a longer disease duration and to have more severe motor symptoms. Conclusions: NPS, most commonly mood disorders (apathy, depression, and anxiety), psychosis, and ICDs are frequent manifestations of PD. The results of this review reflect the need to develop unified validated assessment protocols for NPS in PD, as well as to improve their management in clinical practice.


Assuntos
Apatia , Transtornos Cognitivos , Transtornos Disruptivos, de Controle do Impulso e da Conduta , Doença de Parkinson , Idoso , Ansiedade/psicologia , Transtornos Cognitivos/psicologia , Transtornos Disruptivos, de Controle do Impulso e da Conduta/complicações , Humanos , Masculino , Doença de Parkinson/complicações , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/epidemiologia
10.
Front Neurol ; 13: 799696, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401426

RESUMO

Background: Excessive oscillations at beta frequencies (13-35 Hz) in the subthalamic nucleus (STN) represent a pathophysiological hallmark of Parkinson's disease (PD), which correlates well with parkinsonian symptoms and is reduced in response to standard disease treatments. However, the association of disease-specific regional gray matter (GM) atrophy or cortical thickness (CT) with the presence of STN beta oscillatory activity has been poorly investigated but is of relevance given the potential of these variables for extracting information about PD pathophysiology. This exploratory study investigated the involvement of regional GM volume and CT in the basal ganglia-cortical network and its potential association with the presence of STN beta oscillatory activity in PD. Methods: We acquired preoperative GM densities on T1-weighted magnetic resonance imaging scans and we carried out regional estimation of GM volume and CT. LFP activities from the STN were recorded post-operatively in 7 cognitively preserved PD patients off dopaminergic medication undergoing deep-brain stimulation surgery. Oscillatory beta power was determined by power spectral density of 4-min resting state STN LFP activity. Spearman partial correlations and regression analysis were used to screen the presence of STN beta power for their relationship with GM volume and CT measurements. Results: After controlling for the effects of age, educational level, and disease duration, and after correcting for multiple testing, enhanced STN beta power showed significant and negative correlations between, first, volume of the right putamen and left caudate nucleus, and second, smaller CT in frontal regions involving the left rostral middle frontal gyrus (MFG) and left medial orbitofrontal gyrus. A lower volume in the right putamen and a lower CT in the left MFG demonstrated the strongest associations with increased STN beta power. Conclusions: These tentative results seem to suggest that STN LFP beta frequencies may be mainly linked to different but ongoing parallel neurodegenerative processes, on the one hand, to GM volume reduction in dorsal striatum, and on the other hand, to CT reduction of prefrontal-"associative" regions. These findings could further delineate the brain structural interactions underpinning the exaggerated STN beta activity commonly observed in PD patients.

11.
Invest New Drugs ; 29(5): 984-95, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20449627

RESUMO

In cancer chemotherapy neutropenia is a common dose-limiting toxicity. An ability to predict the neutropenic effects of cytotoxic agents based on proposed trial designs and models conditioned on previous studies would be valuable. The aim of this study was to evaluate the ability of a semi-mechanistic pharmacokinetic/pharmacodynamic (PK/PD) model for myelosuppression to predict the neutropenia observed in Phase I clinical studies, based on parameter estimates obtained from prior trials. Pharmacokinetic and neutropenia data from 5 clinical trials for diflomotecan and from 4 clinical trials for indisulam were used. Data were analyzed and simulations were performed using the population approach with NONMEM VI. Parameter sets were estimated under the following scenarios: (a) data from each trial independently, (b) pooled data from all clinical trials and (c) pooled data from trials performed before the tested trial. Model performance in each of the scenarios was evaluated by means of predictive (visual and numerical) checks. The semi-mechanistic PK/PD model for neutropenia showed adequate predictive ability for both anti-cancer agents. For diflomotecan, similar predictions were obtained for the three scenarios. For indisulam predictions were better when based on data from the specific study, however when the model parameters were conditioned on data from trials performed prior to a specific study, similar predictions of the drug related-neutropenia profiles and descriptors were obtained as when all data were used. This work provides further indication that modeling and simulation tools can be applied in the early stages of drug development to optimize future trials.


Assuntos
Antineoplásicos/efeitos adversos , Camptotecina/análogos & derivados , Descoberta de Drogas , Modelos Biológicos , Neutropenia/induzido quimicamente , Sulfonamidas/efeitos adversos , Adulto , Idoso , Antineoplásicos/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Neutropenia/sangue , Valor Preditivo dos Testes , Sulfonamidas/administração & dosagem , Resultado do Tratamento
12.
Artigo em Inglês | MEDLINE | ID: mdl-34465616

RESUMO

BACKGROUND AND OBJECTIVES: To determine the relative importance of global or regional MRI and blood markers of neurodegeneration and neuroaxonal injury in predicting cognitive performance for recently diagnosed patients with multiple sclerosis (MS). METHODS: Thirty-five newly diagnosed patients with relapsing-remitting MS (RRMS) and 23 healthy controls (HCs) simultaneously completed a full clinical and neuropsychological assessment, structural brain MRI, and serum neurofilament light chain (sNfL) level test. Linear regression analyses were performed to determine which global or regional measures of gray matter (GM) atrophy and cortical thickness (CT), in combination with sNfL levels and clinical scores, are most strongly related to neuropsychological impairment. RESULTS: Compared with HCs, patients with MS showed bilateral thalamic GM atrophy (left, p = 0.033; right, p = 0.047) and diminished CT, particularly in the right superior and transverse temporal gyri (p = 0.045; p = 0.037). Regional atrophy failed to add predictive variance, whereas anxiety symptoms, sNfL, and global CT were the best predictors (R2 = 0.404; p < 0.001) of cognitive outcomes, with temporal thickness accounting for greater variance in cognitive deficits than global CT. DISCUSSION: Thalamic GM atrophy and thinning in temporal regions represent a distinctive MRI trait in the early stages of MS. Although sNfL levels alone do not clearly differentiate HCs and patients with RRMS, in combination with global and regional CT, sNfL levels can better explain the presence of underlying cognitive deficits. Hence, cortical thinning and sNfL increases can be considered 2 parallel neurodegenerative markers in the pathogenesis of progression in newly diagnosed patients with MS.


Assuntos
Córtex Cerebral/patologia , Disfunção Cognitiva , Esclerose Múltipla Recidivante-Remitente , Proteínas de Neurofilamentos/sangue , Tálamo/patologia , Adolescente , Adulto , Córtex Cerebral/diagnóstico por imagem , Disfunção Cognitiva/sangue , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/sangue , Esclerose Múltipla Recidivante-Remitente/complicações , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Esclerose Múltipla Recidivante-Remitente/patologia , Tálamo/diagnóstico por imagem , Adulto Jovem
13.
Arch Clin Neuropsychol ; 36(4): 475-484, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33067616

RESUMO

OBJECTIVE: This retrospective observational study aimed to define neuropsychological impairment (NI) profiles and determine the influence of clinical, demographic, and neuropsychiatric measures in specific cognitive domains in a cohort of relapsing-remitting multiple sclerosis (RRMS) patients. METHODS: Ninety-one RRMS patients underwent a neurological examination and a brief neuropsychological assessment. Patients were classified according to the disease-modifying therapies (DMTs) received (platform or high-efficacy). Differences between groups and multiple regression analyses were performed to determine the predictive value of the assessed measures in cognitive performance. RESULTS: More than two-thirds of the patients showed NI. Specifically, mild to moderate NI was presented in approximately half of the participants. Paced Auditory Serial Addition Test (PASAT-3) and Symbol Digit Modalities Test (SDMT) were the most frequently impaired cognitive tests (45.3% and 41.3%, respectively) followed by phonemic verbal fluency (PVF) (27.8%). Expanded Disability Status Scale (EDSS), age, depressive symptoms, and disease duration were the best predictors of SDMT (R2 = .34; p < .01), whereas disease duration, EDSS, and anxiety-state levels predicted PASAT-3 (R2 = .33, p < .01). Educational level, age, EDSS, and depressive symptoms demonstrated the strongest association with PVF (R2 = .31, p < .01). CONCLUSIONS: Our results indicated a significant prevalence of NI in RRMS patients that was not dependent on the DMT type. In addition to the meaningful working memory (PASAT-3) and information processing speed (SDMT) impairments found, PVF deficits may also be an important marker of cognitive impairment in RRMS patients. This study supports the relevance of standard clinical measures and reinforces the importance of quantifying clinical and neuropsychiatric symptoms to predict subsequent cognitive performance on a similar multiple sclerosis phenotype and disease stage.


Assuntos
Transtornos Cognitivos , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Neuropsiquiatria , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Humanos , Esclerose Múltipla Recidivante-Remitente/complicações , Testes Neuropsicológicos
14.
Pharm Res ; 27(2): 340-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20039105

RESUMO

PURPOSE: To establish an in vitro-in vivo level A correlation (IVIVC) for pramipexole slow-release formulations. METHODS: The IVIVC was developed based on data from an immediate-release (IR) and three slow-release (SR) formulations of pramipexole; a fourth SR formulation was used for validation purposes. In vitro dissolution profiles were obtained from all SR formulations. Fifteen volunteers received all pramipexole formulations in a randomized cross-over trial. Data were analyzed using the population modelling approach as implemented in NONMEM VI. RESULTS: Dissolution profiles of the SR formulations were described by the Weibull model. The pharmacokinetics of the IR formulation were described by a two-compartment disposition model with first-order absorption. Difference between the in vivo and in vitro estimates of the release rate constants (k(d)) from the Weibull function suggests the release process occurs faster in vivo. Pharmacokinetic profiles for SR formulations were described based on the in vitro release model with k(d) increased in 0.058 h(-1) and the population pharmacokinetic model developed from the IR formulation. CONCLUSION: A level A IVIVC was established and evaluated for the pramipexole SR formulations, which can be used in the future as a surrogate to avoid certain bioequivalence studies.


Assuntos
Benzotiazóis/administração & dosagem , Benzotiazóis/farmacocinética , Modelos Químicos , Administração Oral , Adolescente , Benzotiazóis/sangue , Química Farmacêutica , Estudos Cross-Over , Preparações de Ação Retardada , Humanos , Pessoa de Meia-Idade , Pramipexol , Solubilidade
15.
CPT Pharmacometrics Syst Pharmacol ; 9(10): 553-560, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32830463

RESUMO

The oral Janus kinase 1 (JAK1) inhibitor abrocitinib reduced signs and symptoms of atopic dermatitis (AD) in a placebo-controlled, randomized, double-blind, phase IIb trial (dose range 10-200 mg). A kinetic-pharmacodynamic (K-PD) model consisting of proliferation, maturation, and blood circulation compartments was developed to characterize platelet count changes during the study. The K-PD model consisted of a drug elimination constant, four system parameters describing platelet dynamics, variance terms, correlation, and residual errors. Overall, these patients exhibited mean transit time from progenitor cells to platelets of 8.2 days (longer than the reported megakaryocyte life span), likely arising from JAK1-induced perturbations of platelet progenitor homeostasis. The final model described dose-related platelet count declines until nadir at treatment week 4 and return to baseline levels thereafter. The model was deemed suitable to support the design of subsequent abrocitinib AD trials and indicated limited clinically relevant platelet reductions in the range of doses studied.


Assuntos
Plaquetas/efeitos dos fármacos , Dermatite Atópica/tratamento farmacológico , Janus Quinase 1/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/farmacocinética , Sulfonamidas/farmacocinética , Administração Oral , Adulto , Desenho de Fármacos , Homeostase , Humanos , Cinética , Células Progenitoras de Megacariócitos/efeitos dos fármacos , Placebos/administração & dosagem , Contagem de Plaquetas/estatística & dados numéricos , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/administração & dosagem , Pirimidinas/uso terapêutico , Índice de Gravidade de Doença , Sulfonamidas/administração & dosagem , Sulfonamidas/uso terapêutico
16.
Foods ; 9(3)2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32143400

RESUMO

Increase in allergenicity towards cow's milk, lactose intolerance, the prevalence of hypercholesterolemia, and flexitarian choice of food consumption have increased the market for cow's milk alternatives. Non-dairy plant-based beverages are useful alternatives because of the presence of bioactive components with health-promoting properties, which attract health-conscious consumers. However, the reduced nutritional value and sensory acceptability of the plant-based beverages (such as flavor, taste, and solubility) compared to cow's milk pose a big threat to its place in the market. Thermal treatments are commonly used to ensure the quality of plant-based beverages during storage. However, the application of high temperatures can promote the degradation of thermolabile compounds and some detrimental reactions, thus reducing protein digestibility and amino acid availability of non-dairy plant-based beverages substitutes. New and advanced food processing technologies, such as high-pressure processing, high-pressure homogenization, pulsed electric fields, and ultrasound, are being researched for addressing the issues related to shelf life increase, emulsion stability, preservation of nutritional content and sensorial acceptability of the final product. However, the literature available on the application of non-thermal processing technologies on the physicochemical and nutritional properties of plant-based beverages is scarce. Concerted research efforts are required in the coming years in the functional plant-based beverages sector to prepare newer, tailor-made products which are palatable as well as nutritionally adequate.

17.
Clin Pharmacol Ther ; 106(3): 652-660, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30993686

RESUMO

Linked pharmacometric and pharmacoeconomic models provide a structured approach for assessing the value of candidate drugs in development. The aim of this study was to assess the utility of such an approach for identifying the properties of xanthine oxidase inhibitors (XOi) providing improved forgiveness to nonadherence and estimate the maximum reimbursement price. The pharmacometric and pharmacoeconomic models were used to simulate the time course of serum uric acid concentrations and estimate quality-adjusted life years and costs for the XOi febuxostat and a range of hypothetical analogues. Compounds with reduced clearance or increased potency were more forgiving to missed doses, however, even following relatively large changes in these properties the predicted maximum reimbursement prices represented an increase of only 19% above febuxostat 80 mg. Linked pharmacometric and pharmacoeconomic modeling methods have the potential to inform early drug development by providing an indication of pricing options that may permit reimbursement.


Assuntos
Febuxostat/farmacocinética , Supressores da Gota/farmacocinética , Gota/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Xantina Oxidase/antagonistas & inibidores , Alopurinol/economia , Alopurinol/uso terapêutico , Simulação por Computador , Análise Custo-Benefício , Custos e Análise de Custo , Monitoramento de Medicamentos , Farmacoeconomia , Febuxostat/economia , Febuxostat/uso terapêutico , Supressores da Gota/economia , Supressores da Gota/uso terapêutico , Humanos , Reembolso de Seguro de Saúde/estatística & dados numéricos , Anos de Vida Ajustados por Qualidade de Vida , Ácido Úrico/sangue
18.
Food Res Int ; 120: 888-894, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31000310

RESUMO

The effect of supercritical carbon dioxide (SC-CO2) (10-40 MPa) and conventional extraction (CE) to recover oil from by-products obtained during "horchata" production was assessed. To evaluate both extraction techniques, the fatty acid composition, polyphenols, α-tocopherol, antioxidant capacity and lipid oxidation parameters of the extracts obtained were analysed. A linear relationship between extraction pressure and oil yield was observed. However, the highest oil yield was obtained under conventional extraction. The by-products from "horchata" presented a profile where monounsaturated fatty acids (MUFA) were the predominant, representing ≈ 70% of total fatty acids. The amount of saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA) was higher and MUFA lower at 10 MPa samples compared to the oils extracted using SC-CO2 at 20, 30 or 40 MPa, where no differences were detected. The content of α-tocopherol was significantly higher after SC-CO2 treatments compared to conventional extraction, independently of the applied treatment. On the other hand, the values of phenolic compounds and total antioxidant activity (TAC) increased as the pressure conditions of the SC-CO2 extraction increased, presenting a linear adjustment of the data. Regarding lipid oxidation, the lower oxidation indexes were obtained when the SC-CO2 pressure increased. Finally, our results confirmed that the application of SC-CO2 could be a potential alternative to conventional extraction in order to obtain oils from "horchata" by-products rich in high-added value compounds without the use of organic solvents which can be toxic.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Cyperus , Ácidos Graxos/análise , Fenóis/análise , Óleos de Plantas/análise , alfa-Tocoferol/análise , Dióxido de Carbono , Oxirredução , Pressão
19.
Food Chem ; 274: 865-871, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30373021

RESUMO

In this study, the effect of different supercritical CO2 (SC-CO2) pressures (10-40 MPa) on phenolic compounds extraction in oils obtained from "horchata" by-products was evaluated, and the results were compared to those obtained after conventional oil extraction (CE). Moreover, the relationship between the individual phenolic compounds and the total antioxidant capacity as well as oil oxidative quality parameters was compared. The phenolic profile and contents were largely influenced by extracting conditions. The main phenolic compound obtained by SC-CO2 was the isohydroxymatairesinol, particularly at 30 and 40 MPa, while 3-vinylphenol was the predominant compound in oils extracted by CE procedure. Increasing SC-CO2 extraction pressures enhanced the extraction of phenolic compounds, along with improving the antioxidant capacity and oxidative quality of extracted oil. The principal component analysis indicated that the main phenolic compounds associated with TEAC values were those extracted by SC-CO2, which were inversely correlated to oxidative indexes.


Assuntos
Antioxidantes/farmacologia , Fracionamento Químico/métodos , Lipídeos/química , Fenóis/análise , Óleos de Plantas/química , Antioxidantes/química , Dióxido de Carbono , Cromatografia Líquida/métodos , Indústria de Processamento de Alimentos , Oxirredução , Pressão , Análise de Componente Principal , Espectrometria de Massas em Tandem/métodos , Resíduos
20.
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