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1.
Pharmaceutics ; 15(5)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37242636

RESUMO

Peritonitis is a limiting complication of peritoneal dialysis, which is treated by intraperitoneal administration of antibiotics. Various dosing strategies are recommended for intraperitoneally administered vancomycin, which leads to large differences in intraperitoneal vancomycin exposure. Based on data from therapeutic drug monitoring, we developed the first-ever population pharmacokinetic model for intraperitoneally administered vancomycin to evaluate intraperitoneal and plasma exposure after dosing schedules recommended by the International Society for Peritoneal Dialysis. According to our model, currently recommended dosing schedules lead to possible underdosing of a large proportion of patients. To prevent this, we suggest avoiding intermittent intraperitoneal vancomycin administration, and for the continuous dosing regimen, we suggest a loading dose of 20 mg/kg followed by maintenance doses of 50 mg/L in each dwell to improve the intraperitoneal exposure. Vancomycin plasma level measurement on the fifth day of treatment with subsequent dose adjustment would prevent it from reaching toxic levels in the few patients who are susceptible to overdose.

2.
J Chemother ; 35(7): 614-622, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36715134

RESUMO

The aim of this study was to describe and quantify pharmacokinetics of ampicillin used prophylactically in cardiac surgery both with and without cardiopulmonary bypass (CPB) using population pharmacokinetic analysis in order to propose an optimal dosing strategy. Adult patients undergoing cardiac surgery and treated with prophylactic dose of 2 g ampicillin were enrolled to this prospective study. Blood samples were collected according to the study protocol and ampicillin plasma concentrations were measured using HPLC/UV system. A three-stage population pharmacokinetic model using nonlinear mixed-effects modelling approach was developed. Totally 273 blood samples obtained from 20 patients undergoing cardiac surgery with the use of the CPB and 20 patients without CPB use were analyzed. Two-comparmental model best fits ampicillin concentration-time data. Mean ± SD body weight-normalized ampicillin central and peripheral volume of distribution was 0.12 ± 0.02 L/kg and 0.15 ± 0.03 L/kg, respectively, while mean ± SD ampicillin clearance in typical patient with eGFR of 1.5 mL/s/1.73 m2 was 1.17 ± 0.05 L/h. The use of CPB did not significantly affect the pharmacokinetics of ampicillin. When administering 2 g of ampicillin before surgery, an additional dose should be administered to reach the PK/PD target of fT > MIC = 50% if the operation lasts longer than 430 min in patients with moderate to severe renal impairment, 320 min in patients with mild renal impairment, 220 min in patients with normal renal function status or 140 min in patients with an augmented renal clearance.


Assuntos
Antibacterianos , Procedimentos Cirúrgicos Cardíacos , Adulto , Humanos , Antibacterianos/uso terapêutico , Ponte Cardiopulmonar/efeitos adversos , Ponte Cardiopulmonar/métodos , Estudos Prospectivos , Ampicilina
3.
Br J Clin Pharmacol ; 89(4): 1452-1461, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36422512

RESUMO

AIM: The objective of this study was to evaluate off-label high-dose ceftazidime population pharmacokinetics in cancer patients with suspected or proven extensively drug-resistant (XDR) Pseudomonas aeruginosa infections and then to compare the achievement of the pharmacokinetic/pharmacodynamic (PK/PD) target after standard and off-label high-dose regimens using population model-based simulations. A further aim was to clinically observe the occurrence of adverse effects during the off-label high-dose ceftazidime treatment. METHODS: In patients treated with off-label high-dose ceftazidime (3 g every 6 h), blood samples were collected and ceftazidime serum levels measured using LC-MS/MS. A pharmacokinetic population model was developed using a nonlinear mixed-effects modelling approach and Monte Carlo simulations were then used to compare standard and high-dose regimens for PK/PD target attainment. RESULTS: A total of 14 cancer patients with serious infection suspected of XDR P. aeruginosa aetiology were eligible for PK analysis. XDR P. aeruginosa was confirmed in 10 patients as the causative pathogen. Population ceftazidime volume of distribution was 13.23 L, while clearance started at the baseline of 1.48 L/h and increased by 0.0076 L/h with each 1 mL/min/1.73 m2 of eGFR. High-dose regimen showed significantly higher probability of target attainment (i.e., 86% vs. 56% at MIC of 32 mg/L). This was translated into a very low mortality rate of 20%. Only one case of reversible neurological impairment was observed. CONCLUSION: We proved the superiority of the ceftazidime off-label high-dose regimen in PK/PD target attainment with very low occurrence of adverse effects. The off-label high-dose regimen should be used to optimize treatment of XDR P. aeruginosa infections.


Assuntos
Neoplasias , Infecções por Pseudomonas , Humanos , Ceftazidima/efeitos adversos , Ceftazidima/farmacocinética , Infecções por Pseudomonas/tratamento farmacológico , Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Cromatografia Líquida , Uso Off-Label , Pseudomonas aeruginosa , Espectrometria de Massas em Tandem , Método de Monte Carlo , Testes de Sensibilidade Microbiana , Neoplasias/complicações , Neoplasias/tratamento farmacológico
4.
Artigo em Inglês | MEDLINE | ID: mdl-35147137

RESUMO

AIMS: The neuropeptide galanin is a widely distributed neurotransmitter/neuromodulator that regulates a variety of physiological processes and also participates in the regulation of stress responses. The aims of the present study were to investigate the expression of galanin receptors (GalR1, GalR2, GalR3) in the spinal cords in a murine model of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE) using qPCR analysis and to determine GalR1 cellular localization (oligodendrocytes, microglia, astrocytes, ependymal cells, and endothelial cells in the capillaries) by immunohistochemistry. METHODS: Twelve samples from the EAE group and 14 samples from the control group were analyzed. Spinal cords samples were obtained at the peak of the EAE disease. RESULTS: The GalR1 mRNA level was significantly decreased in the EAE mice compared with the controls (P=0.016), whereas the mRNA levels of GalR2 and GalR3 were not significantly different for the EAE and the control mice. No significant correlations were found between the severity of the EAE disease and the mRNA levels of GalR1, GalR2 and GalR3. Immunochemical detection of the GalR1 revealed its expression in the ependymal and endothelial cells. Additionally, a weak GalR1 immunoreactivity was occasionally detected in the oligodendrocytes. CONCLUSION: This study provides additional evidence of galanin involvement in EAE pathophysiology, but this has to be further investigated.


Assuntos
Encefalomielite Autoimune Experimental , Galanina , Camundongos , Animais , Receptores de Galanina/genética , Receptores de Galanina/metabolismo , Galanina/genética , Galanina/metabolismo , Células Endoteliais , Receptor Tipo 2 de Galanina/genética , Receptor Tipo 2 de Galanina/metabolismo , RNA Mensageiro/metabolismo , Medula Espinal/metabolismo
5.
Antibiotics (Basel) ; 11(11)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36358235

RESUMO

The objectives of this study were to develop a population pharmacokinetic model of prophylactically administered cefazolin in patients undergoing cardiac surgery with and without the use of the cardiopulmonary bypass of both existing types-standard (ECC) and minimallyu invasive extracorporeal circulation (MiECC)-and to propose cefazoline dosing optimization based on this model. A total of 65 adult patients undergoing cardiac surgery were recruited to this clinical trial. A prophylactic cefazolin dose of 2 g was intravenously administered before surgery. Blood samples were collected using a rich sampling design and cefazolin serum concentrations were measured using the HPLC/UV method. The pharmacokinetic population model was calculated using a nonlinear mixed-effects modeling approach, and the Monte Carlo simulation was used to evaluate the PK/PD target attainment. The population cefazolin central volume of distribution (Vd) of 4.91 L increased by 0.51 L with each 1 m2 of BSA, peripheral Vd of 22.07 L was reduced by 0.77 L or 0.79 L when using ECC or MiECC support, respectively, while clearance started at 0.045 L/h and increased by 0.49 L/h with each 1 mL/min/1.73 m2 of eGFR. ECC/MiECC was shown to be covariate of cefazolin Vd, but without relevance to clinical practice, while eGFR was most influential for the PK/PD target attainment. The standard dose of 2 g was sufficient for PK/PD target attainment throughout surgery in patients with normal renal status or with renal impairment. In patients with augmented renal clearance, an additive cefazolin dose should be administered 215, 245, 288 and 318 min after the first dose at MIC of 4, 3, 2 and 1.5 mg/L, respectively.

6.
Physiol Res ; 71(1): 147-157, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35043649

RESUMO

The aim of this study was to evaluate therapeutic potential of edaravone in the murine model of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE) and to expand the knowledge of its mechanism of action. Edaravone (6 mg/kg/day) was administered intraperitoneally from the onset of clinical symptoms until the end of the experiment (28 days). Disease progression was assessed daily using severity scores. At the peak of the disease, histological analyses, markers of oxidative stress (OS) and parameters of mitochondrial function in the brains and spinal cords (SC) of mice were determined. Gene expression of inducible nitric oxide synthase (iNOS), nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha was determined at the end of the experiment. Edaravone treatment ameliorated EAE severity and attenuated inflammation in the SC of the EAE mice, as verified by histological analysis. Moreover, edaravone treatment decreased OS, increased the gene expression of the Nrf2 and HO-1, increased the activity of the mitochondrial complex II/III, reduced the activity of the mitochondrial complex IV and preserved ATP production in the SC of the EAE mice. In conclusion, findings in this study provide additional evidence of edaravone potential for the treatment of multiple sclerosis and expand our knowledge of the mechanism of action of edaravone in the EAE model.


Assuntos
Encefalomielite Autoimune Experimental , Encefalomielite , Animais , Edaravone/farmacologia , Encefalomielite Autoimune Experimental/patologia , Expressão Gênica , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Índice de Gravidade de Doença
7.
Minerva Pediatr (Torino) ; 74(2): 107-115, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33107271

RESUMO

BACKGROUND: The current study uses a population modeling approach to evaluate and quantify the impact of severity of asphyxia and hypoxic-ischemic encephalopathy (HIE) on the pharmacokinetics of phenobarbital in asphyxiated newborns treated with therapeutic hypothermia. METHODS: Included newborns received phenobarbital (the TOBY trial protocol). 120 plasma samples were available from 50 newborns, median (IQR) weight 3.3 (2.8-3.5) kg and gestational age 39 (39-40) weeks. NONMEM® version 7.2 was used for the data analysis. Age, body weight, sex, concomitant medications, kidney and liver function markers, as well as severity parameters of asphyxia and HIE were tested as potential covariates of pharmacokinetics of phenobarbital. Severe asphyxia was defined as pH of arterial umbilical cord blood ≤7.1 and Apgar 5 ≤5, and severe HIE was defined as time to normalization of amplitude-integrated electroencephalography (aEEG) >24 h. RESULTS: Weight was found to be the only statistically significant covariate for the volume of distribution. At weight of 1 kg volume of distribution was 0.91 L and for every additional kg it increased in 0.91 L. Clearance was 0.00563 L/h. No covariates were statistically significant for the clearance of phenobarbital. CONCLUSIONS: Phenobarbital dose adjustments are not indicated in the studied population, irrespective of the severity of asphyxia or HIE.


Assuntos
Asfixia Neonatal , Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Adulto , Asfixia/complicações , Asfixia/tratamento farmacológico , Asfixia Neonatal/complicações , Asfixia Neonatal/tratamento farmacológico , Humanos , Hipotermia Induzida/métodos , Hipóxia-Isquemia Encefálica/terapia , Recém-Nascido , Fenobarbital/farmacocinética , Fenobarbital/uso terapêutico
8.
Eur J Clin Pharmacol ; 78(1): 89-98, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34414464

RESUMO

PURPOSE: Data on the anti-Xa efficacy of fondaparinux in dialysis-dependent chronic kidney disease (DD-CKD) patients are scarce. This study characterizes the pharmacokinetics (PK) and pharmacodynamics (PD) of fondaparinux in DD-CKD patients undergoing renal replacement therapy (RRT), to assess dosing strategies. METHODS: A retrospective, observational study was conducted using data on anti-Xa activity (112 samples) from 12 (3 male and 9 female) DD-CKD patients (median (IQR) age 71 years (63-88), weight 73 kg (59-98.5)). Eleven patients underwent high-flux or low-flux hemodialysis (HD) and one patient underwent peritoneal dialysis. Three patients were also treated with therapeutic plasma exchange (TPE). A non-linear mixed effects analysis was performed using NONMEM 7.3.0. RESULTS: The lab-specific slope of the relationship between fondaparinux concentration and anti-Xa levels was 1.18 IU/µg. In a one-compartment model, clearance (CL) and volume of distribution (Vd) were 0.05289 L/h and 5.55 L, respectively. High-flux HD was found to increase the CL of fondaparinux 2.26 times. TPE also considerably increased CL, but the fold-change could not be accurately estimated. Low-flux HD and peritoneal dialysis did not impact PK parameters. CONCLUSIONS: Model-based simulations showed that standard dosing (2.5 mg three times weekly before HD) results in a median anti-Xa activity of 0.55 IU/mL and 0.98 IU/mL, pre- and post-low-flux HD, respectively. In patients undergoing high-flux HD, these values are approximately 27% lower. Additional caution is warranted with TPE, as this treatment can reduce anti-Xa activity even further.


Assuntos
Inibidores do Fator Xa/farmacocinética , Fondaparinux/farmacocinética , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/terapia , Terapia de Substituição Renal , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Inibidores do Fator Xa/farmacologia , Feminino , Fondaparinux/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Pharmaceutics ; 13(8)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34452118

RESUMO

The aim of this prospective PK study was to evaluate the pharmacokinetics of ciprofloxacin dosed within the first 36 h (early phase) and after 3 days of treatment (delayed phase) using individual and population PK analysis. The secondary aim of the study was to evaluate possible dosing implications of the observed PK differences between early and delayed phases to achieve a PK/PD target for ciprofloxacin of AUC24/MIC ≥ 125. Blood concentrations of ciprofloxacin (1 and 4 h after dose and trough) were monitored in critically ill adults in the early and delayed phases of the treatment. Individual and population PK analyses were performed. Complete concentration-time profiles in the early phase, delayed phase, and both phases were obtained from 29, 15, and 14 patients, respectively. No systematic changes in ciprofloxacin PK parameters between the early and delayed phases were observed, although variability was higher at the early phase. Both individual and population analyses provided similar results. Simulations showed that after standard dosing, it is practically impossible to reach the recommended ciprofloxacin PK/PD target (AUC/MIC ≥ 125) for pathogens with MIC ≥ 0.5 mg/L. A dosing nomogram utilizing patients' creatinine clearance and MIC values was constructed. Both individual and population analyses provided similar results. Therapeutic drug monitoring should be implemented to safeguard the optimal ciprofloxacin exposure.

11.
World J Psychiatry ; 11(7): 277-296, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34327122

RESUMO

Schizophrenia is a severe psychiatric disorder characterized by emotional, behavioral and cognitive disturbances, and the treatment of schizophrenia is often complicated by noncompliance and pharmacoresistance. The search for the pathophysiological mechanisms underlying schizophrenia has resulted in the proposal of several hypotheses to explain the impacts of environmental, genetic, neurodevelopmental, immune and inflammatory factors on disease onset and progression. This review discusses the newest insights into the pathophysiology of and risk factors for schizophrenia and notes novel approaches in antipsychotic treatment and potential diagnostic and theranostic biomarkers. The current hypotheses focusing on neuromediators (dopamine, glutamate, and serotonin), neuroinflammation, the cannabinoid hypothesis, the gut-brain axis model, and oxidative stress are summarized. Key genetic features, including small nucleotide polymorphisms, copy number variations, microdeletions, mutations and epigenetic changes, are highlighted. Current pharmacotherapy of schizophrenia relies mostly on dopaminergic and serotonergic antagonists/partial agonists, but new findings in the pathophysiology of schizophrenia have allowed the expansion of novel approaches in pharmacotherapy and the establishment of more reliable biomarkers. Substances with promising results in preclinical and clinical studies include lumateperone, pimavanserin, xanomeline, roluperidone, agonists of trace amine-associated receptor 1, inhibitors of glycine transporters, AMPA allosteric modulators, mGLUR2-3 agonists, D-amino acid oxidase inhibitors and cannabidiol. The use of anti-inflammatory agents as an add-on therapy is mentioned.

12.
Pharmaceutics ; 13(3)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33668911

RESUMO

Phenobarbital is a first-line treatment of various seizure types in newborns. Dosage individualization maximizing the proportion of patients with drug levels in therapeutic range or sufficient treatment response is still challenging. The aim of this review was to summarize the available evidence on phenobarbital pharmacokinetics in neonates and to identify its possible covariates suitable for individualization of initial drug dosing. Several covariates have been considered: body weight and height, body surface area, gestational and postnatal age, laboratory parameters of renal and hepatic functions, asphyxia, therapeutic hypothermia, extracorporeal membrane oxygenation (ECMO), drug interactions, and genetic polymorphisms. The most frequently studied and well-founded covariate for the estimation of phenobarbital dosing is actual body weight. Loading dose of 15-20 mg/kg followed by a maintenance dose of 3-5 mg/kg/day seems to be accurate. However, the evidence for the other covariates with respect to dosing individualization is not sufficient. Doses at the lower limit of suggested range should be preferred in patients with severe asphyxia, while the upper limit of the range should be targeted in neonates receiving ECMO support.

13.
Prague Med Rep ; 121(4): 244-253, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33270012

RESUMO

The post-mortem toxicological findings may be misinterpreted, if the drug undergoes substantial post-mortem redistribution. As alprazolam is one of the most frequently evaluated drug for legal/forensic reasons in drug-related fatalities, we studied possible changes in alprazolam distribution after death in a rat model. Rats were sacrificed 30 minutes after alprazolam administration. Blood and tissue samples from 8 animals per sampling time were collected at 0, 2, 6, and 24 h after death. The experimental samples were assayed for alprazolam using validated UHPLC-PDA method. Median blood alprazolam concentrations increased approximately 2 times compared with ante-mortem levels due to the redistribution during early post-mortem phase and then slowly decreased with a half-life of 60.7 h. The highest alprazolam tissue concentrations were found in fat and liver and the lowest levels were observed in lungs and brain. The median amount of alprazolam deposited in the lungs was relatively stable over the 24-h post-mortem period, while in heart, liver and kidney the deposited proportion of administered dose increased by 43-48% in comparison with ante-mortem values indicating continuous accumulation of alprazolam into these tissues. These results provide evidence needed for the interpretation of toxicological results in alprazolam-related fatalities and demonstrate modest alprazolam post-mortem redistribution.


Assuntos
Alprazolam , Hipnóticos e Sedativos , Alprazolam/farmacocinética , Animais , Hipnóticos e Sedativos/farmacocinética , Mudanças Depois da Morte , Ratos
14.
Pediatr Crit Care Med ; 21(9): e707-e715, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32639476

RESUMO

OBJECTIVES: This study characterizes the changes in the pharmacokinetics of phenobarbital associated with extracorporeal membrane oxygenation treatment in neonates, to illustrate our findings and provide guidance on dosing. DESIGN: Retrospective pilot population pharmacokinetic analysis. SETTING: Neonatal ICU. PATIENTS: Thirteen critically ill neonates (birth body weight, 3.21 kg [2.65-3.72 kg]; postnatal age at start of treatment: 2 d [0-7 d]; gestational age: 38 wk [38-41 wk]) receiving venovenous or venoarterial extracorporeal membrane oxygenation. INTERVENTIONS: Phenobarbital administered in a loading dose of 7.5 mg/kg (8.5-16 mg/kg) and maintenance dose of 6.9 mg/kg/d (4.5-8.5 mg/kg/d). MEASUREMENTS AND MAIN RESULTS: Therapeutic drug monitoring data were available, yielding 5, 31, and 19 phenobarbital concentrations before, during, and after extracorporeal membrane oxygenation, respectively. Population pharmacokinetic analysis was performed using NONMEM 7.3.0 (ICON Development Solutions, Ellicott City, MD). Maturation functions for clearance and volume of distribution were obtained from literature. In a one-compartment model, clearance and volume of distribution for a typical neonate off extracorporeal membrane oxygenation and with a median birth body weight (3.21 kg) at median postnatal age (2 d) were 0.0096 L/hr (relative SE = 11%)) and 2.72 L (16%), respectively. During extracorporeal membrane oxygenation, clearance was found to linearly increase with time. Upon decannulation, phenobarbital clearance initially decreased and subsequently increased slowly driven by maturation. Extracorporeal membrane oxygenation-related changes in volume of distribution could not be identified, possibly due to sparse data collection shortly after extracorporeal membrane oxygenation start. According to the model, target attainment is achieved in the first 12 days of extracorporeal membrane oxygenation with a regimen of a loading dose of 20 mg/kg and a maintenance dose of 4 mg/kg/d divided in two doses with an increase of 0.25 mg/kg every 12 hours during extracorporeal membrane oxygenation treatment. CONCLUSIONS: We found a time-dependent increase in phenobarbital clearance during the first 12 days of extracorporeal membrane oxygenation treatment in neonates, which results in continuously decreasing phenobarbital exposure and increases the risk of therapeutic failure over time. Due to high unexplained variability, frequent and repeated therapeutic drug monitoring should be considered even with the model-derived regimen.


Assuntos
Oxigenação por Membrana Extracorpórea , Adulto , Estado Terminal , Monitoramento de Medicamentos , Humanos , Recém-Nascido , Fenobarbital , Estudos Retrospectivos
15.
Eur J Pharmacol ; 873: 172973, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32017935

RESUMO

Multiple sclerosis (MS) is a neurologic autoimmune disorder featured by chronic inflammation of the central nervous system, demyelination and axonal damage. Recently, the term "oxinflammation" has been proposed to depict the vicious circle of chronic inflammation and oxidative stress (OS). OS promotes demyelination and neurodegeneration directly, by oxidation of lipids, proteins, and DNA but also indirectly, by inducing a dysregulation of the immunity and favoring the state of pro-inflammatory response. Many of the actors of this delicately tuned network are controlled by Keap1/Nrf2/ARE signaling pathway, a principal regulator of antioxidant and phase II detoxification genes. This pathway also has a pivotal role in inflammation, and therefore possesses a great potential in the treatment of MS. The aim of this review is to provide the newest insights in the preclinical and clinical evidence of Nrf2 induction in the regeneration of the antioxidant response and attenuation of inflammation in MS. Preclinical studies have indicated that activators of this pathway, such as epigallocatechin gallate (EGCG), curcumin, melatonin, resveratrol, and sulforaphane might be a promising therapeutic option in amelioration of MS symptoms, nevertheless, the efficacy and safety of these compounds have to be confirmed in future clinical trials.


Assuntos
Proteína 1 Associada a ECH Semelhante a Kelch/efeitos dos fármacos , Esclerose Múltipla/tratamento farmacológico , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteínas de Transporte Vesicular/efeitos dos fármacos , Animais , Humanos
16.
Pulm Circ ; 10(1): 2045894019898031, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32095231

RESUMO

Pharmacokinetic data for riociguat in patients with chronic thromboembolic pulmonary hypertension (CTEPH) have previously been reported from randomized clinical trials, which may not fully reflect the population encountered in routine practice. The aim of the current study was to characterize the pharmacokinetic of riociguat and its metabolite M1 in the patients from routine clinical practice. A population pharmacokinetic model was developed in NONMEM 7.3, based on riociguat and its metabolite plasma concentrations from 49 patients with CTEPH. One sample with riociguat and M1 concentrations was available from each patient obtained at different time points after last dose. Age, bodyweight, sex, smoking status, concomitant medications, kidney and liver function markers were tested as potential covariates of pharmacokinetic of riociguat and its metabolite. Riociguat and M1 disposition was best described with one-compartment models. Apparent volume of distribution (Vd/F) for riociguat and M1 were assumed to be the same. Total bilirubin and creatinine clearance were the most predictive covariates for apparent riociguat metabolic clearance to M1 (CLf,M1/F) and for apparent riociguat clearance through remaining pathways (CLe,r/F), respectively. CLf,M1/F, CLe,r/F, Vd/F of riociguat and M1, and clearance of M1 (CLe,M1/F) for a typical individual with 70 mL/min creatinine clearance and 0.69 mg/dL total bilirubin were 0.665 L/h (relative standard error = 17%)), 0.66 (18%) L/h, 3.63 (15%) L and 1.47 (19%) L/h, respectively. Upon visual identification of six outlying individuals, an absorption lag-time of 2.95 (6%) h was estimated for these patients. In conclusion, the only clinical characteristics related to riociguat exposure in patients with CTEPH from routine clinical practice are total bilirubin and creatinine clearance. This confirms the findings of the previous population pharmacokinetic studies based on data from randomized clinical trials.

17.
J Strength Cond Res ; 34(10): 2965-2973, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30199454

RESUMO

Michalickova, D, Minic, R, Kotur-Stevuljevic, J, Andjelkovic, M, Dikic, N, Kostic-Vucicevic, M, Slanar, O, and Djordjevic, B. Changes in parameters of oxidative stress, immunity, and behavior in endurance athletes during a preparation period in winter. J Strength Cond Res 34(10): 2965-2973, 2020-The current study monitored markers of immunological and oxidative status in 9 male elite endurance athletes: V[Combining Dot Above]O2max: 68 ± 11 ml·kg·min, age: 24 ± 2.5 years, and training loads: 128 ± 21 metabolic equivalents-h·wk during a 3-month preparation period in winter (January-March). Self-rated state of moods evaluation (by Profile of Mood States questionnaire) was performed, and blood samples were collected at the beginning and end of the study. Spectrophotometric methods and enzyme-linked immunosorbent assay were used for parameters' determination. The level of concanavalin A (ConA)-stimulated interferon-γ (IFN-γ) from peripheral blood mononuclear cells (PBMCs) was increased (562 [147-852] vs. 1,097 [451-1842] pg·ml, p = 0.013). Also, the level of transforming growth factor-1 (TGF-ß1) in serum was elevated (2.5 [1.4-5.1] vs. 7.2 [4.9-8.2] ng·ml, p = 0.015). There was no change in the level of peptidoglycan (PGN)-stimulated interleukin (IL)-10 from PBMCs. There were no significant changes in PBMCs proliferation/viability on stimulation with ConA and PGN during the study. No changes in superoxide dismutase, prooxidative-antioxidative balance, total oxidant status (TOS), and thiobarbituric acid reactive substances were observed along the study. Total antioxidant status (TAS) was increased (910 ± 174 vs. 1,090 ± 102 µmol·L, p = 0.018), and activity of paraoxonase (PON1) was decreased (523 ± 295 vs. 335 ± 183 U·L, p = 0.003) at the end of the study. Advanced oxidation protein products were increased (25 ± 7.9 vs. 42 ± 7.6 µmol·L, p = 0.011). The self-rated sense of vigor significantly declined (20 ± 2.1 vs. 14 ± 3.4, p = 0.045). In conclusion, 3 months of regular training in winter induced prominent changes in cytokines, biomarkers of oxidative stress, and antioxidative enzyme activity. These changes might increase susceptibility of athletes to disease and muscle damage and consequently lead to performance reduction.


Assuntos
Afeto/fisiologia , Atletas , Citocinas/metabolismo , Estresse Oxidativo/fisiologia , Resistência Física/fisiologia , Adolescente , Adulto , Biomarcadores , Ensaio de Imunoadsorção Enzimática , Teste de Esforço , Humanos , Leucócitos Mononucleares/metabolismo , Estudos Longitudinais , Masculino , Equivalente Metabólico/fisiologia , Estado Nutricional , Oxirredução , Consumo de Oxigênio/fisiologia , Resistência Física/imunologia , Adulto Jovem
18.
Plant Foods Hum Nutr ; 74(1): 122-127, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30661220

RESUMO

There is a growing body of evidence that tomato consumption reduces the risk of cardiovascular disease, through antioxidative, anti-inflammatory and hypotensive effects. We compared the effects of polyphenol-enriched and standard tomato juice on parameters of lipid and oxidative status and blood pressure in subjects with stage 1 hypertension. The experimental group (n = 13) was supplemented with 200 g of tomato fruit juice enriched with 1 g of ethanolic extract of whole tomato fruit, while the control group (n = 13) was consuming 200 g tomato fruit juice. Before and after the treatment, blood samples were collected, and blood pressure was measured. Markers of oxidative stress and antioxidative defense: paraoxonase (PON1), thiobarbituric acid reactive substances (TBARS), total antioxidant status (TAS), total oxidant status (TOS), pro-oxidant-antioxidant balance (PAB) and C reactive protein (CRP) were determined in serum. Prothrombin time (PT) was measured in the whole blood samples. Parameters of lipid status, as well as susceptibility to copper-induced oxidation of LDL particles in vitro were also determined. There was a significant reduction in total cholesterol and LDL-C only in the control group at the end of the study. No significant differences were observed in the remainder of the assessed parameters along the study. In conclusion, tomato juice may have favorable effects on lipid metabolism, but polyphenol fortification does not constitute additional beneficial cardiovascular effects.


Assuntos
Antioxidantes/farmacologia , Doenças Cardiovasculares/prevenção & controle , Sucos de Frutas e Vegetais/análise , Hipertensão/prevenção & controle , Polifenóis/farmacologia , Solanum lycopersicum/química , Biomarcadores/análise , Pressão Sanguínea/efeitos dos fármacos , Suplementos Nutricionais , Feminino , Humanos , Lipídeos/análise , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Método Simples-Cego
19.
J Hum Kinet ; 64: 111-122, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30429904

RESUMO

A randomized, double-blind, placebo-controlled study was conducted, in order to evaluate if Lactobacillus helveticus Lafti® L10 (Lallemand Health Solutions, Montreal, Canada) supplementation during three months could influence oxidative markers in the population of elite athletes: triathletes, cyclists and endurance athletes. Twenty-two elite athletes were randomized to either placebo (n = 12) or probiotic (n = 10) groups. The probiotic group received 2x1010 colony forming units of Lafti® L10. Before and after the supplementation serum samples were collected. Markers of oxidative stress and anti-oxidative defense: superoxide dismutase (SOD), paraoxonase (PON), advanced oxidation protein products (AOPP), malondialdehyde (MDA), total antioxidant status, total oxidant status, pro-oxidant-antioxidant balance, oxidative stress index, bilirubin, uric acid and albumin were determined in serum. Parameters of lipid status, as well as susceptibility to copper-induced oxidation of LDL particles in vitro were also determined. There was a significant interaction effect for MDA (p = 0.039), with a decrease in MDA in the probiotic group only (p = 0.049). There was a significant interaction effect for AOPP (p = 0.037), with a significant decrease in the probiotic group (p = 0.045). Interaction effect for SOD was approaching to formal significance (p = 0.108) and the post-hoc test showed a significant decrease in the probiotic group (p = 0.041) only. A significant correlation between AOPP and SOD (p = 0.012, r = -0.40) was found in the probiotic group at the end of the study. PON1 activity was decreased in both the probiotic (p = 0.032) and placebo group (p = 0.035). No significant changes in the remainder of the evaluated parameters were noted. In conclusion, probiotic strain Lafti® L10 exerts certain antioxidant potential, but further research is needed.

20.
PLoS One ; 13(9): e0203665, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30252853

RESUMO

The goal of this work was to elucidate similarities between microorganisms from the perspective of the humoral immune system reactivity in professional athletes. The reactivity of serum IgG of 14 young, individuals was analyzed to 23 selected microorganisms as antigens by use of the in house ELISA. Serum IgM and IgA reactivity was also analyzed and a control group of sex and age matched individuals was used for comparison. The obtained absorbance levels were used as a string of values to correlate the reactivity to different microorganisms. IgM was found to be the most cross reactive antibody class, Pearson's r = 0.7-0.92, for very distant bacterial species such as Lactobacillus and E. coli.High correlation in IgG levels was found for Gammaproteobacteria and LPS (from E. coli) (r = 0.77 for LPS vs. P. aeruginosa to r = 0.98 for LPS vs. E.coli), whereas this correlation was lower in the control group (r = 0.49 for LPS vs. P. aeruginosa to r = 0.66 for LPS vs. E.coli). The correlation was also analyzed between total IgG and IgG subclasses specific for the same microorganism, and IgG2 was identified as the main subclass recognising different microorganisms, as well as recognising LPS. Upon correlation of IgG with IgA for the same microorganism absence of or negative correlation was found between bacteria-specific IgA and IgG in case of Lactobacillus and Staphylococcusgeni, whereas correlation was absent or positive for Candida albicans, Enterococcusfaecalis,Streptococcus species tested in professional athletes. Opposite results were obtained for the control group. Outlined here is a simple experimental procedure and data analysis which yields functional significance and which can be used for determining the similarities between microorganisms from the aspect of the humoral immune system, for determining the main IgG subclass involved in an immune response as well as for the analysis of different target populations.


Assuntos
Anticorpos Antibacterianos/sangue , Especificidade de Anticorpos , Atletas , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunidade Humoral , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino
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