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Multidrug resistance proteins type 4 (MRP4) and 5 (MRP5) play pivotal roles in the transport of cyclic nucleotides in various tissues. However, their specific functions within the lower urinary tract remain relatively unexplored. This study aimed to investigate the effect of pharmacological inhibition of MRPs on cyclic nucleotide signaling in isolated pig bladder. The relaxation responses of the bladder were assessed in the presence of the MRP inhibitor, MK571. The temporal changes in intra- and extracellular levels of cAMP and cGMP in stimulated tissues were determined by mass spectrometry. The gene (ABCC4) and protein (MRP4) expression were also determined. MK571 administration resulted in a modest relaxation effect of approximately 26% in carbachol-precontracted bladders. The relaxation induced by phosphodiesterase inhibitors such as cilostazol, tadalafil, and sildenafil was significantly potentiated in the presence of MK571. In contrast, no significant potentiation was observed in the relaxation induced by substances elevating cAMP levels or stimulators of soluble guanylate cyclase. Following forskolin stimulation, both intracellular and extracellular cAMP concentrations increased by approximately 15.8-fold and 12-fold, respectively. Similarly, stimulation with tadalafil + BAY 41-2272 resulted in roughly 8.2-fold and 3.4-fold increases in intracellular and extracellular cGMP concentrations, respectively. The presence of MK571 reduced only the extracellular levels of cGMP. This study reveals the presence and function of MRP4 transporters within the porcine bladder and paves the way for future research exploring the role of this transporter in both underactive and overactive bladder disorders.NEW & NOTEWORTHY This study investigates the impact of pharmacological inhibition of MRP4 and MRP5 transporters on cyclic nucleotide signaling in isolated pig bladders. MK571 administration led to modest relaxation, with enhanced effects observed in the presence of phosphodiesterase inhibitors. However, substances elevating cAMP levels remained unaffected. MK571 selectively reduced extracellular cGMP levels. These findings shed light on the role of MRP4 transporters in the porcine bladder, opening avenues for further research into bladder disorders.
Assuntos
GMP Cíclico , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Bexiga Urinária , Animais , Bexiga Urinária/metabolismo , Bexiga Urinária/efeitos dos fármacos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , GMP Cíclico/metabolismo , Suínos , Quinolinas/farmacologia , AMP Cíclico/metabolismo , Relaxamento Muscular/efeitos dos fármacos , Masculino , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Feminino , Transdução de Sinais , Inibidores de Fosfodiesterase/farmacologia , PropionatosRESUMO
New Psychoactive Substances (NPSs) are defined as a group of substances produced from molecular modifications of traditional drugs. These molecules represent a public health problem since information about their metabolites and toxicity is poorly understood. N-ethyl pentedrone (NEP) is an NPS that was identified in the illicit market for the first time in the mid-2010s, with four intoxication cases later described in the literature. This study aims to evaluate the metabolic stability of NEP as well as to identify its metabolites using three liver microsomes models. To investigate metabolic stability, NEP was incubated with rat (RLM), mouse (MLM) and human (HLM) liver microsomes and its concentration over time evaluated by liquid chromatography-mass spectrometry. For metabolite identification, the same procedure was employed, but the samples were analyzed by liquid chromatography-high resolution mass spectrometry. Different metabolism profiles were observed depending on the model employed and kinetic parameters were determined. The in vitro NEP elimination half-lives (t1/2) were 12.1, 187 and 770 min for the rat, mouse and human models, respectively. Additionally, in vitro intrinsic clearances (Cl int, in vitro) were 229 for rat, 14.8 for mouse, and 3.6 µL/min/mg in the human model, and in vivo intrinsic clearances (Cl int, in vivo) 128, 58.3, and 3.7 mL/min/kg, respectively. The HLM model had the lowest rate of metabolism when compared to RLM and MLM. Also, twelve NEP metabolites were identified from all models, but at different rates of production.
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Cyclic Nucleotides are important in regulating platelet function. Increases in 3'5'-cyclic adenosine monophosphate (cAMP) and 3'5'-cyclic guanosine monophosphate (cGMP) inhibit platelet aggregation and are pharmacological targets for antiplatelet therapy. Here we report an improved method for determining cAMP and cGMP concentrations and, for the first time, in washed platelet supernatants by combining high-performance liquid chromatography and tandem mass spectrometry (LC-MS/MS). Characteristic peaks of the substrates, cGMP or cAMP and their internal standards were identified in negative-ion electrospray ionisation using multiple reaction monitoring. Compared with previously reported methods, the method presented here shows high precision with the lowest lower limit of quantification (LLoQ) to date (10 pg/mL). The effect of a novel catecholamine, 6-nitrodopamine, on cyclic nucleotide levels was quantified. Our results showed that this new method was fast, sensitive, and highly reproducible.
Assuntos
AMP Cíclico , GMP Cíclico , Cromatografia Líquida/métodos , GMP Cíclico/análise , GMP Cíclico/química , AMP Cíclico/análise , Espectrometria de Massas em Tandem/métodos , Agregação Plaquetária , Plaquetas/químicaRESUMO
AIM: In the Roux-en-Y gastric bypass technique, classic laparoscopic surgical retractors are usually rigid, require an additional incision for its installation, or must be handled by an assistant during the surgical procedure, involving a risk of liver injury. The aim of this study was to evaluate and validate a technique of the esophagogastric junction exposure obtained by the flexible liver retractor in bariatric surgery, comparing its efficacy with the retractor classically used for this purpose. METHODS: This study was performed as a randomized, open, prospective, controlled, and comparative design in patients with medical indications of bariatric surgery. The subjects were distributed in the classic (control) and flexible (test) retractor groups. RESULTS: A total of 100 patients (n=50 control group, n=50 test group) were included. No statistically significant difference was observed in the mean duration of surgery. Regarding visibility, 100% of the patients in the flexible retractor group demonstrated an optimal visibility level, although without statistical significance concerning the classic retractor group (94%). Invariably, carrying a trocar was necessary when using the classic retractor. CONCLUSIONS: The flexible liver retractor is safe, effective, ergonomic, and inexpensive. Furthermore, it presented a satisfactory aesthetic profile, and the use of specific instruments, new adaptation curve, and training for its handling were not required.
OBJETIVOS: Os afastadores clássicos de cirurgia laparoscópica são geralmente rígidos, necessitando de uma incisão adicional para sua instalação ou de um auxiliar para manuseio durante o ato cirúrgico e ainda, podem envolvem risco de injúria hepática. Avaliar e validar uma técnica de exposição da junção esofagogástrica obtida pelo afastador flexível de fígado em cirurgia bariátrica comparando sua eficácia com a de afastador classicamente utilizado para este fim. MÉTODOS: Tratou-se de um estudo prospectivo, aberto, controlado e comparativo em pacientes com indicação de cirurgia, distribuídos de forma randomizada em dois grupos: clássico (controle) e afastador flexível (teste). RESULTADOS: Foram incluídos 100 pacientes (n=50 grupo controle, n=50 grupo teste), sem diferença estatística na distribuição por idade e por morbidades, havendo diferença estatística somente no gênero (grupo controle obteve proporção maior de homens, p=0,020). Em relação ao tempo médio de realização das operações, não foi constatada diferença estatística. No quesito visibilidade, verificou-se que 100% dos pacientes do grupo afastador flexível obteve nível de visibilidade ótima, porém sem significância estatística com relação ao grupo clássico (94%). Invariavelmente, foi necessário um portal a mais de trocarte quando do uso do afastador clássico. CONCLUSÃO: O afastador flexível de fígado demonstrou-se seguro, eficaz, ergonômico, de baixo custo, de perfil estético satisfatório, não requerendo instrumental específico para uso ou nova curva de adaptação e aprendizado para manuseio.
Assuntos
Cirurgia Bariátrica , Derivação Gástrica , Obesidade Mórbida , Junção Esofagogástrica/cirurgia , Humanos , Estudos ProspectivosRESUMO
This study predicted dapaconazole clinical drug−drug interactions (DDIs) over the main Cytochrome P450 (CYP) isoenzymes using static (in vitro to in vivo extrapolation equation, IVIVE) and dynamic (PBPK model) approaches. The in vitro inhibition of main CYP450 isoenzymes by dapaconazole in a human liver microsome incubation medium was evaluated. A dapaconazole PBPK model (Simcyp version 20) in dogs was developed and qualified using observed data and was scaled up for humans. Static and dynamic models to predict DDIs following current FDA guidelines were applied. The in vitro dapaconazole inhibition was observed for all isoforms investigated, including CYP1A2 (IC50 of 3.68 µM), CYP2A6 (20.7 µM), 2C8 (104.1 µM), 2C9 (0.22 µM), 2C19 (0.05 µM), 2D6 (0.87 µM), and 3A4 (0.008−0.03 µM). The dynamic (PBPK) and static DDI mechanistic model-based analyses suggest that dapaconazole is a weak inhibitor (AUCR > 1.25 and <2) of CYP1A2 and CYP2C9, a moderate inhibitor (AUCR > 2 and <5) of CYP2C8 and CYP2D6, and a strong inhibitor (AUCR ≥ 5) of CYP2C19 and CYP3A, considering a clinical scenario. The results presented may be a useful guide for future in vivo and clinical dapaconazole studies.
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Introduction: Oral cancer refers to malignant tumors, of which 90% are squamous cell carcinomas (OSCCs). These malignancies exhibit rapid progression, poor prognosis, and often mutilating therapeutical approaches. The determination of a prophylactic and/or therapeutic antitumor role of the polyphenolic extract Polypodium leucotomos(PL) would be relevant in developing new tools for prevention and treatment. Methods: We aimed to determine the antitumor effect of PL by treating OSCC cell lines with PL metabolites and evaluating its action during OSCC progression in vivo. Results: PL treatment successfully impaired cell cycling and proliferation, migration, and invasion, enhanced apoptosis, and modulated macrophage polarization associated with the tumoral immune-inflammatory response of tongue cancer cell lines (TSCC). PL treatment significantly decreased the expression of MMP1 (p < 0.01) and MMP2 (p < 0.001), and increased the expression of TIMP1 (p < 0.001) and TIMP2 (p < 0.0001) in these cells. The mesenchymal-epithelial transition phenotype was promoted in cells treated with PL, through upregulation of E-CAD (p < 0.001) and reduction of N-CAD (p < 0.05). PL restrained OSCC progression in vivo by inhibiting tumor volume growth and decreasing the number of severe dysplasia lesions and squamous cell carcinomas. Ki-67 was significantly higher expressed in tongue tissues of animals not treated with PL(p < 0.05), and a notable reduction in Bcl2 (p < 0.05) and Pcna (p < 0.05) cell proliferation-associated genes was found in dysplastic lesions and TSCCs of PL-treated mice. Finally, N-cad(Cdh2), Vim, and Twist were significantly reduced in tongue tissues treated with PL. Conclusion: PL significantly decreased OSCC carcinogenic processes in vitro and inhibited tumor progression in vivo. PL also appears to contribute to the modulation of immune-inflammatory oral tumor-associated responses. Taken together, these results suggest that PL plays an important antitumor role in processes associated with oral carcinogenesis and may be a potential phytotherapeutic target for the prevention and/or adjuvant treatment of TSCCs.
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In this study, the development and validation of a method for quantification of 6-nitrodopamine in Krebs-Henseleit's solution by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) with positive ion electrospray ionization is described. Aortic rings taken from tortoise were either denuded or left with endothelium intact (15 mm, N = 6) and were incubated for 30 min in 5 mL Krebs-Henseleit's solution in an organ bath. Solid phase extraction (SPE) was performed for aliquots of 1 mL of the supernatant. The separation of 6-nitrodopamine was obtained on a 150 mm × 3 mm Shim-pack GIST-HP C18 column, using 75% of mobile phase A consisted of deionized water with 0.1% formic acid (v/v) and 25% of mobile phase B consisted of acetonitrile/deionized water (50/50, v/v) + 0.1% formic acid at a flow rate of 350 µL/min in an isocratic mode. The method was linear over the concentration range of 0.1-20 ng/mL. The method was sensitive, precise and accurate for the assessment of the basal release of 6-nitrodopamine from Chelonoidis carbonaria aortae in vitro. The mean ± SEM concentrations of 6-nitrodopamine released from endothelium-intact and endothelium-denuded aortae were 0.44 ± 0.06 ng/mL and 0.18 ± 0.05 ng/mL, respectively. These results indicate that tortoise's aortae display a basal endothelium-derived 6-nitrodopamine release.
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PURPOSE: To evaluate the pharmacokinetics and pharmacodynamics of oestriol (E3) and trimegestone (TMG) in healthy women after application of three different vaginal rings over 21 days. The vaginal rings had a nominal delivery rate of 0.413/0.050 mg/day (Test 1), 0.311/0.090 mg/day (Test 2) and 0.209/0.137 mg/day (Test 3) E3/TMG. METHODS: Thirty-five healthy women were randomised to receive a single application of Test 1, 2 or 3 (Clinical Trial NCT03343912). The E3 and TMG plasma concentration was determined by LC-MS/MS. Oestradiol (E2) and progesterone (PG) serum concentrations, and bleeding patern were determined as pharmacodynamic parameters. Safety was assessed by evaluation of adverse events and local tolerability. RESULTS: The total and maximum exposure of E3 and TMG increased in a proportional ratio to dose. However, not in a magnitude which was expected from the dose differences for E3. During Test 2 and 3 treatment all E2 and PG values remained on a well suppressed level until end of treatment. E2 and PG serum levels increased distinctly earlier after ring removal with Test 1 compared to Test 2 and 3. Test 3 achieved 95.24% of "no bleeding" days under treatment followed by Test 1 (91.67%), and Test 2 (86.15%). CONCLUSIONS: The Test 3 formulation presented the best dose combination of E3/TMG for contraception. Moreover, all vaginal rings were well tolerated.
Assuntos
Anticoncepcionais Femininos/administração & dosagem , Dispositivos Anticoncepcionais Femininos , Estriol/farmacologia , Estriol/farmacocinética , Estrogênios/metabolismo , Promegestona/análogos & derivados , Administração Intravaginal , Adulto , Cromatografia Líquida , Estradiol/sangue , Estrogênios/sangue , Feminino , Humanos , Progesterona/sangue , Promegestona/farmacocinética , Promegestona/farmacologia , Espectrometria de Massas em TandemRESUMO
The aim of this study was to develop and validate a UHPLC-MS/MS assay to quantify cyclosporin (CYC), tacrolimus (TAC), sirolimus (SIR) and everolimus (EVE) in human whole blood for therapeutic drug monitoring. Analytes were extracted from 50 µL human whole blood by protein precipitation. The separation of the drugs was performed on an Acquity UPLC BEH C18 column. Analytes were eluted with a mobile phase consisting of 2 mM ammonium acetate with 0.1% formic acid (v/v) in deionised water and 2 mM ammonium acetate with 0.1% formic acid (v/v) in methanol at a flow rate of 300 µL/min in gradient elution. The method performance was evaluated by analysing patient blood samples and/or external quality control samples [proficiency testing (PT) scheme]. The method was linear from 23.75 to 1094.0, 1.3 to 42.4, 1.3 to 47.0 and 1.2-41.6 µg/mL for CYC, TAC, SIR and EVE, respectively. The within- and between-assay reproducibility results were Ë 11%. Results from PT and patient sample quantification were comparable to those obtained previously by an in-house validated method using protein precipitation and liquid-liquid extraction. This method showed good analytical performance for quantifying CYC, TAC, SIR and EVE in whole blood over their respective calibration ranges.
Assuntos
Ciclosporina/sangue , Monitoramento de Medicamentos/métodos , Everolimo/sangue , Imunossupressores/sangue , Sirolimo/sangue , Tacrolimo/sangue , Cromatografia Líquida de Alta Pressão , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas em TandemRESUMO
This study presents, for the first time, the development and validation of a liquid chromatography and time-of-flight mass-spectrometry (LC-TOF-MS) based assay to quantify mycophenolic acid (MPA) in patient samples as part of a routine therapeutic drug monitoring service. MPA was extracted from 50 µl human plasma by protein precipitation, using sulindac as internal standard (IS). Separation was obtained on a Luna™ Omega polar C18 column kept at 40°C. The mobile phase consisted of a mixture of acetonitrile-deionized water (50:50, v/v) with 0.1% formic acid at a flow rate of 350 µl/min. Analyte and IS were monitored on a TOF-MS using a Jet-Stream™ (electrospray) interface running in positive mode. Assay performance was evaluated by analysing patient plasma (N = 69) and external quality assessment (N = 6) samples. The retention times were 2.66 and 2.18 min for MPA and IS, respectively. The lower limit of quantification of MPA was 0.1 µg/ml. The within- and between-assay reproducibility results ranged from 1.81 to 10.72%. Patient and external quality assessment sample results were comparable with those obtained previously by an in-house validated LC-MS/MS method. This method showed satisfactory analytical performance for the determination of MPA in plasma over the calibration range of 0.1-15.0 µg/ml.
Assuntos
Cromatografia Líquida/métodos , Monitoramento de Medicamentos/métodos , Imunossupressores/sangue , Ácido Micofenólico/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Humanos , Imunossupressores/química , Imunossupressores/farmacocinética , Modelos Lineares , Ácido Micofenólico/química , Ácido Micofenólico/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
This study presented for the first time the development and validation of a sensitive method for quantification of dopamine, noradrenaline, and adrenaline in Krebs-Henseleit solution by LC-tandem mass spectrometry. Aliquots of 2.0 mL calibrators, quality controls, and samples of Krebs-Henseleit solution incubated with tortoise's aortic ring for 30 min were extracted by solid-phase extraction. Catecholamine separation was achieved on a 100 × 4.6 mm LiChrospher RP-8 column and the quantification was performed by a mass spectrometer equipped with an electrospray interface operating in positive ion mode. The run time was 4 min and the calibration curve was linear over the range of 0.1-20.0 ng/mL. The method was applied to the measurement of basal release of dopamine, noradrenaline, and adrenaline from the tortoise Chelonoidis carbonaria aortae in vitro. One aortic ring (30 mm) per tortoise (n = 5) was incubated for 30 min in a 5 mL organ bath filled with Krebs-Henseleit solution. The method demonstrated sensitivity, precision, and accuracy enough for its application in the measurement of basal release of these catecholamines from C. carbonaria aortic rings in vitro. The mean (standard deviation) concentrations of dopamine, noradrenaline, and adrenaline were 3.48 (2.55) ng/mL, 1.40 (0.57) ng/mL, and 1.87 (1.09) ng/mL, respectively.
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Aorta/metabolismo , Monoaminas Biogênicas , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Monoaminas Biogênicas/análise , Monoaminas Biogênicas/metabolismo , Monoaminas Biogênicas/farmacocinética , Células Cultivadas , Feminino , Glucose/química , Modelos Lineares , Masculino , Artéria Pulmonar/citologia , Artéria Pulmonar/metabolismo , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Suínos , Trometamina/química , Tartarugas/metabolismoRESUMO
RESUMO - RACIONAL: Os afastadores clássicos de cirurgia laparoscópica são geralmente rígidos, necessitando de uma incisão adicional para sua instalação ou de um auxiliar para manuseio durante o ato cirúrgico e ainda, podem envolvem risco de injúria hepática. OBJETIVOS: Avaliar e validar uma técnica de exposição da junção esofagogástrica obtida pelo afastador flexível de fígado em cirurgia bariátrica comparando sua eficácia com a de afastador classicamente utilizado para este fim. MÉTODOS: Tratou-se de um estudo prospectivo, aberto, controlado e comparativo em pacientes com indicação de cirurgia, distribuídos de forma randomizada em dois grupos: clássico (controle) e afastador flexível (teste). RESULTADOS: Foram incluídos 100 pacientes (n=50 grupo controle, n=50 grupo teste), sem diferença estatística na distribuição por idade e por morbidades, havendo diferença estatística somente no gênero (grupo controle obteve proporção maior de homens, p=0,020). Em relação ao tempo médio de realização das operações, não foi constatada diferença estatística. No quesito visibilidade, verificou-se que 100% dos pacientes do grupo afastador flexível obteve nível de visibilidade ótima, porém sem significância estatística com relação ao grupo clássico (94%). Invariavelmente, foi necessário um portal a mais de trocarte quando do uso do afastador clássico. CONCLUSÃO: O afastador flexível de fígado demonstrou-se seguro, eficaz, ergonômico, de baixo custo, de perfil estético satisfatório, não requerendo instrumental específico para uso ou nova curva de adaptação e aprendizado para manuseio.
ABSTRACT - BACKGROUND: In the Roux-en-Y gastric bypass technique, classic laparoscopic surgical retractors are usually rigid, require an additional incision for its installation, or must be handled by an assistant during the surgical procedure, involving a risk of liver injury. Aim: The aim of this study was to evaluate and validate a technique of the esophagogastric junction exposure obtained by the flexible liver retractor in bariatric surgery, comparing its efficacy with the retractor classically used for this purpose. Methods: This study was performed as a randomized, open, prospective, controlled, and comparative design in patients with medical indications of bariatric surgery. The subjects were distributed in the classic (control) and flexible (test) retractor groups. Results: A total of 100 patients (n=50 control group, n=50 test group) were included. No statistically significant difference was observed in the mean duration of surgery. Regarding visibility, 100% of the patients in the flexible retractor group demonstrated an optimal visibility level, although without statistical significance concerning the classic retractor group (94%). Invariably, carrying a trocar was necessary when using the classic retractor. Conclusions: The flexible liver retractor is safe, effective, ergonomic, and inexpensive. Furthermore, it presented a satisfactory aesthetic profile, and the use of specific instruments, new adaptation curve, and training for its handling were not required.
Assuntos
Humanos , Obesidade Mórbida , Derivação Gástrica , Cirurgia Bariátrica , Estudos Prospectivos , Junção Esofagogástrica/cirurgiaRESUMO
To assess the bioequivalence of two zolpidem hemitartrate formulations in 30 healthy volunteers. Plasma samples were obtained over a 24 h period. Plasma concentrations of zolpidem were analyzed by liquid chromatography coupled to tandem mass spectrometry with positive ion electrospray ionization using multiple reaction monitoring. Values of peak concentration (Cmax ), area under curve (AUC), half-life, elimination constant, volume of distribution and clearance showed statistically significant differences when comparing women (604.34 ng h/ml, 127.36 ng/ml, 4.4 h, 0.18 1/h, 50.56 L and 8.55 L/h, respectively) and men (276.1 ng h/ml, 70.9 ng/ml, 3.3 h, 0.26 1/h, 91.42 L and 24.34 L/h, respectively), receiving the same dose (5 mg), respectively. The geometric means with corresponding 90% confidence interval for Test/Reference percentage ratios were 99.73% (CI 93.69-106.16) for Cmax, 97.44% (90% CI = 91.85-103.37%) for area under curve of plasma concentration until the last concentration observed (AUClast ) and 98.30% (90% CI = 92.48-104.49) for the area under curve between the first sample (pre-dosage) and infinity (AUC0-inf ). Since the 90% CI for AUClast , AUC0-inf and Cmax ratios were within the 80-125% interval proposed by the US Food and Drug Administration, it was concluded that zolpidem hemitartrate formulation (5 mg orodispersible tablet) is bioequivalent to the zolpidem hemitartrate formulation (Patz SL 5 mg sublingual tablet) with regard to both the rate and the extent of absorption. A new formulation of zolpidem 2.5 mg may be useful in women for the same clinical benefits as the 5 mg formulation in men.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Zolpidem/sangue , Zolpidem/farmacocinética , Adulto , Disponibilidade Biológica , Brasil , Feminino , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Comprimidos , Adulto Jovem , Zolpidem/químicaRESUMO
The combination of medroxyprogesterone acetate 25 mg + estradiol cypionate 5 mg is a highly effective, monthly injectable contraceptive. For the first time, this study presents the development and validation of a sensitive method for estradiol cypionate analysis in human plasma by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Aliquots (500 µL) of plasma were extracted with ethyl ether (100%) and derivatized with dansyl chloride. Its separation was performed on a Jones Chromatography Genesis C8 column and the quantification was performed with a mass spectrometer equipped with an electrospray interface operating in negative ion mode. The run time was 6 min and the calibration curve was linear over the range of 0.005-0.15 ng/mL. The method was applied to evaluate the pharmacokinetics of estradiol cypionate in plasma collected up to 1008 h (42 days) after a single intramuscular administration of 25 mg/mL medroxyprogesterone acetate +5 mg/mL estradiol cypionate to healthy female volunteers (n = 12). The estradiol cypionate maximum plasma concentration (Cmax) was 0.14 ± 0.08 ng/mL reached at 16.83 ± 21.07 h and the area under the plasma concentration versus time curve (AUC0-last) was 14.07 ± 6.32 ng.h/mL. Elimination half-life (t½), apparent volume of distribution (Vd/F), apparent clearance (CL/F) and mean residence time (MRT) were 89.65 ± 76.04 h, 28038 ± 9636 L, 49.02 ± 10.62 L/h and 576.05 ± 238.32 h, respectively, showing that the estradiol cypionate release from the administration site was prolonged and there was no drug accumulation.
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Estradiol/análogos & derivados , Estradiol/farmacocinética , Plasma/química , Adulto , Calibragem , Cromatografia Líquida/métodos , Feminino , Voluntários Saudáveis , Humanos , Injeções Intramusculares , Cinética , Acetato de Medroxiprogesterona/farmacocinética , Espectrometria de Massas em Tandem/métodos , Adulto JovemRESUMO
BACKGROUND AND OBJECTIVES: Nanotechnology may increase the speed of penetration into the skin. This study evaluated the efficacy, safety, and pharmacokinetics of a novel topical anesthetic nanocapsule formulation (2 g) containing 2.5% lidocaine and 2.5% prilocaine (nanorap-test formulation) compared to placebo (control formulation) in skin types I-III patients of both sexes submitted to the ablative fractional CO2 laser treatment. METHODS: The patients (n = 120) included in this double-blind, single-center, randomized trial, received topical application of 2 g of the test formulation (50 mg lidocaine + 50 mg prilocaine) and placebo on the forehead region. Efficacy was assessed as pain sensation in four quadrants of each side of the forehead using a visual analogue scale immediately (0 min) and at 30, 60, and 90 minutes after laser application compared to placebo. The safety and tolerability of the test product were evaluated based on the occurrence of systemic adverse events as well as the occurrence of immediate and late skin reactions. Pharmacokinetic evaluation was performed in plasma of eight patients using a validated LC-MS/MS method for drugs quantification. RESULTS: Nanorap induced a clinically significant reduction in the pain assessment at all evaluated times (57.2%, 41.6%, 38.6%, and 37.3% at 0, 30, 60, and 90 minutes after drug application, respectively. Mean values of Cmax were 14.20 and 5.36 ng/ml and tmax were 3.5 and 1.8 hour for lidocaine and prilocaine, respectively. No systemic adverse events were observed. CONCLUSION: The nanorap formulation demonstrated a clinically and statistically significant efficacy providing analgesia after the ablative fractional CO2 laser therapy in the investigated patients, when compared to placebo. The product also presented good safety and tolerability. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.
Assuntos
Anestésicos Locais/administração & dosagem , Lasers de Gás/efeitos adversos , Combinação Lidocaína e Prilocaína/administração & dosagem , Nanocápsulas , Dor Processual/prevenção & controle , Adolescente , Adulto , Idoso , Anestésicos Locais/farmacocinética , Anestésicos Locais/uso terapêutico , Método Duplo-Cego , Feminino , Testa , Humanos , Combinação Lidocaína e Prilocaína/farmacocinética , Combinação Lidocaína e Prilocaína/uso terapêutico , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Medição da Dor , Dor Processual/diagnóstico , Dor Processual/etiologia , Adulto JovemRESUMO
BACKGROUND: Bariatric surgery leads to several anatomo-physiological modifications that may affect pharmacokinetic parameters and consequently alter the therapeutic effect of drugs, such as antibiotics. The pharmacokinetics of oral amoxicillin after Roux-en-Y gastric bypass (RYGB) surgery is unknown. OBJECTIVES: The objective of this study was to evaluate the impact of bariatric surgery on the pharmacokinetics of amoxicillin. METHODS: This study was performed as a randomized, open-label, single-dose clinical trial, with two periods of treatment, in which obese subjects (n = 8) received an amoxicillin 500 mg capsule orally before and 2 months after the RYGB surgery. The amoxicillin plasma concentration was determined by liquid chromatography coupled to mass spectrometry (LC-MS/MS). RESULTS: After the surgery, the mean weight loss was 17.03 ± 5.51 kg, and mean body mass index (BMI) decreased from 46.21 ± 2.82 to 38.82 ± 3.32 kg/m2. The mean amoxicillin area under the plasma concentration versus time curve from time zero to the time of the last quantifiable concentration (AUC0-tlast) increased significantly (3.5-fold); the maximum plasma concentration (Cmax) increased 2.8-fold after the bariatric surgery. No correlation was found between amoxicillin absorption, BMI, and weight loss percentage. CONCLUSION: The alterations observed in the amoxicillin pharmacokinetics suggest that obese subjects included in this trial had a substantially increase in amoxicillin systemic exposure after RYGB surgery. However, despite this increase, its exposure was lower than the values reported for non-obese volunteers. TRIAL REGISTRATION: Identifiers: NCT03588273.
Assuntos
Amoxicilina/farmacocinética , Antibacterianos/farmacocinética , Derivação Gástrica , Obesidade Mórbida/metabolismo , Obesidade Mórbida/cirurgia , Redução de Peso/fisiologia , Administração Oral , Adulto , Amoxicilina/administração & dosagem , Amoxicilina/sangue , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Índice de Massa Corporal , Cromatografia Líquida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/sangue , Espectrometria de Massas em TandemAssuntos
Dispositivos Anticoncepcionais Femininos , Estriol/farmacocinética , Terapia de Reposição Hormonal/métodos , Pós-Menopausa/efeitos dos fármacos , Administração Intravaginal , Idoso , Relação Dose-Resposta a Droga , Esquema de Medicação , Estriol/administração & dosagem , Estriol/efeitos adversos , Feminino , Hormônio Foliculoestimulante/sangue , Voluntários Saudáveis , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Estudos Longitudinais , Hormônio Luteinizante/sangue , Pessoa de Meia-Idade , Pós-Menopausa/sangue , Globulina de Ligação a Hormônio Sexual/análiseRESUMO
BACKGROUND: Riluzole is a benzothiazole anticonvulsant used in the treatment of patients with amyotrophic lateral sclerosis and it is being investigated for clinical use in patients with spinal cord injury. The present study evaluated the pharmacokinetics of riluzole in beagle dogs after oral dose administration. METHODS: The oral doses (1.5, 5, 15 and 50 mg/kg) of riluzole were administered to beagle dogs and blood samples were collected from 0 h to 24 h post drug administration. Riluzole was quantified by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). RESULTS: The method was sensitive, precise, accurate and selective to riluzole quantification in plasma of beagle dogs. The pharmacokinetics following oral administration was linear from 1.5 to 15 mg/kg and the t1/2 was 2.16, 1.5, 1.8 and 3.0 h after oral administration of 1.5, 5.0, 15 and 50 mg/kg riluzole. CONCLUSION: The riluzole pharmacokinetics was linear up to 15 mg/kg and had a significantlyshorter t1/2 in beagle dogs than in humans.
Assuntos
Riluzol/farmacocinética , Administração Oral , Animais , Área Sob a Curva , Cromatografia Líquida/métodos , Cães , Feminino , Masculino , Plasma/metabolismo , Riluzol/sangue , Riluzol/farmacologia , Traumatismos da Medula Espinal/sangue , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Espectrometria de Massas em Tandem/métodosRESUMO
This study describes the development and validation of a method for the analysis of unbound plasma concentrations of oxcarbazepine (OXC) and of the enantiomers of its active metabolite 10-hydroxycarbazepine (MHD) [S-(+)- and R-(-)-MHD] using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Additionally, the free fraction of the drug is described in healthy volunteers (n=12) after the oral administration of 300mg OXC/12h for 5days. Plasma aliquots of 200µL were submitted to ultrafiltration procedure and 50µL of the ultrafiltrate were extracted with a mixture of tert-butyl methyl ether:dichloromethane (2:1, v/v). OXC and the MHD enantiomers were separated on a OD-H chiral phase column. The method was linear in the range of 4.0-2.0µg/mL for OXC and of 20.0-6.0µg/mL plasma for the MHD enantiomers. The limit of quantification was 4ng for OXC and 20ng for each MHD enantiomer/mL plasma. The intra- and inter-day precision and inaccuracy were less than 15%. The free fraction at the time of peak plasma concentration of OXC was 0.27 for OXC, 0.37 for S-(+)-MHD and 0.42 for R-(-)-MHD. Enantioselectivity in the free fraction of MHD was observed, with a higher proportion of R-(-)-MHD compared to S-(+)-MHD.
Assuntos
Anticonvulsivantes/sangue , Carbamazepina/análogos & derivados , Pró-Fármacos/análise , Administração Oral , Adulto , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/química , Anticonvulsivantes/farmacocinética , Carbamazepina/administração & dosagem , Carbamazepina/sangue , Carbamazepina/química , Carbamazepina/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Voluntários Saudáveis , Humanos , Oxcarbazepina , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Reprodutibilidade dos Testes , Estereoisomerismo , Espectrometria de Massas em Tandem/métodos , Adulto JovemRESUMO
Oxcarbazepine is indicated for the treatment of partial or generalised tonic-clonic seizures. Most of the absorbed oxcarbazepine is converted into its active metabolite, 10-hydroxycarbazepine (MHD), which can exist as R-(-)- and S-(+)-MHD enantiomers. Here we describe the influence of the P-glycoprotein (P-gp) inhibitor verapamil, on the disposition of oxcarbazepine and MHD enantiomers, both of which are P-gp substrates. Healthy subjects (n=12) were randomised to oxcarbazepine or oxcarbazepine combined with verapamil at doses of 300mg b.i.d. and 80mg t.i.d., respectively. Blood samples (n=185) were collected over a period of 12h post oxcarbazepine dose. An integrated PK model was developed using nonlinear mixed effects modelling using a meta-analytical approach. The pharmacokinetics of oxcarbazepine was described by a two-compartment model with absorption transit compartments and first-order elimination. The concentration-time profiles of both MHD enantiomers were characterised by a one-compartment distribution model. Clearance estimates (95% CI) were 84.9L/h (69.5-100.3) for oxcarbazepine and 2.0L/h (1.9-2.1) for both MHD enantiomers. The volume of distribution was much larger for oxcarbazepine (131L (97-165)) as compared to R-(-)- and S-(+)-MHD (23.6L (14.4-32.8) vs. 31.7L (22.5-40.9), respectively). Co-administration of verapamil resulted in a modest increase of the apparent bioavailability of oxcarbazepine by 12% (10-28), but did not affect parent or metabolite clearances. Despite the evidence of comparable systemic levels of OXC and MHD following administration of verapamil, differences in brain exposure to both moieties cannot be excluded after P-glycoprotein inhibition.