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1.
Ann Neurol ; 93(1): 131-141, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36222470

RESUMEN

OBJECTIVE: Little is known about residual cognitive function in the earliest stages of serious brain injury. Functional neuroimaging has yielded valuable diagnostic and prognostic information in chronic disorders of consciousness, such as the vegetative state (also termed unresponsive wakefulness syndrome). The objective of the current study was to determine if functional neuroimaging could be efficacious in the assessment of cognitive function in acute disorders of consciousness, such as coma, where decisions about the withdrawal of life-sustaining therapies are often made. METHODS: A hierarchical functional magnetic resonance imaging (fMRI) approach assessed sound perception, speech perception, language comprehension, and covert command following in 17 critically ill patients admitted to the intensive care unit (ICU). RESULTS: Preserved auditory function was observed in 15 patients (88%), whereas 5 (29%) also had preserved higher-order language comprehension. Notably, one patient could willfully modulate his brain activity when instructed to do so, suggesting a level of covert conscious awareness that was entirely inconsistent with his clinical diagnosis at the time of the scan. Across patients, a positive relationship was also observed between fMRI responsivity and the level of functional recovery, such that patients with the greatest functional recovery had neural responses most similar to those observed in healthy control participants. INTERPRETATION: These results suggest that fMRI may provide important diagnostic and prognostic information beyond standard clinical assessment in acutely unresponsive patients, which may aid discussions surrounding the continuation or removal of life-sustaining therapies during the early post-injury period. ANN NEUROL 2023;93:131-141.


Asunto(s)
Lesiones Encefálicas , Trastornos de la Conciencia , Humanos , Trastornos de la Conciencia/diagnóstico , Enfermedad Crítica , Encéfalo/diagnóstico por imagen , Lesiones Encefálicas/diagnóstico por imagen , Estado Vegetativo Persistente/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Neuroimagen Funcional , Neuroimagen
2.
Can J Neurol Sci ; 50(1): 23-27, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-34670638

RESUMEN

BACKGROUND: A one-channel electrocardiogram (ECG) channel is recommended during electroencephalogram (EEG) recordings principally to help establish ECG or pulse wave contamination of the ECG EEG. However, the ECG recording, in itself, provides useful clinical information, principally the detection of arrhythmias, especially atrial fibrillation (AF), which indicates heart disease that can predispose to embolic stroke and systemic embolism. We sought to determine the prevalence of AF routine recordings in our EEG laboratory in a general hospital. METHODS: We reviewed the consecutive EEG reports for the past 7 years to determine how often AF was detected in various age groups. RESULTS: We found AF in 0-0.2% per decade of life until age 60-69 years, 2.7% for 70-79 years, 5% for 80-89 years, and 8% for 90-99 years. CONCLUSION: We suggest that the ECG trace should be carefully analyzed for AF, especially in patients over 60 years of age. When detected, it should be brought to the referring doctor's attention.


Asunto(s)
Fibrilación Atrial , Accidente Cerebrovascular , Humanos , Persona de Mediana Edad , Anciano , Electrocardiografía , Frecuencia Cardíaca , Electroencefalografía , Accidente Cerebrovascular/diagnóstico
3.
Xenobiotica ; : 1-36, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37971300

RESUMEN

Polyethylene glycol (PEG) was introduced into synthetic bilirubin 3α and a PEGylated bilirubin 3α nanoparticle (BX-001N, Brixelle®) was developed for the first time.An in vitro microsomal stability study, in vivo PK studies with intravenous bolus (IV) and subcutaneous injection (SC), and a semi-mass balance study of BX-001N were investigated to evaluate its pharmacokinetic (PK) properties in male Sprague-Dawley (SD) rats using developed liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-qTOF/MS).Following IV administration at 10 or 30 mg/kg, BX-001N showed very low clearance (0.33-0.67 mL/min/kg) with predominant distribution in the vascular system (Vd = 51.73-83.02 mL/kg). BX-001N was also very stable in vitro liver microsomal stability study.Following SC administration at 10 or 30 mg/kg, the bioavailability of BX-001N in plasma at 10 mg/kg was around 43% and showed the less dose-proportionality at 30 mg/kg dose.BX-001N was mainly excreted via the urinary pathway (86.59-92.99% of total amount of parent drug in excreta; urine and feces) not via the biliary one.

4.
Molecules ; 28(7)2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37049985

RESUMEN

There have been many attempts in pharmaceutical industries and academia to improve the pharmacokinetic characteristics of anti-tumor small-molecule drugs by conjugating them with large molecules, such as monoclonal antibodies, called ADCs. In this context, albumin, one of the most abundant proteins in the blood, has also been proposed as a large molecule to be conjugated with anti-cancer small-molecule drugs. The half-life of albumin is 3 weeks in humans, and its distribution to tumors is higher than in normal tissues. However, few studies have been conducted for the in vivo prepared albumin-drug conjugates, possibly due to the lack of robust bioanalytical methods, which are critical for evaluating the ADME/PK properties of in vivo prepared albumin-drug conjugates. In this study, we developed a bioanalytical method of the albumin-conjugated MAC glucuronide phenol linked SN-38 ((2S,3S,4S,5R,6S)-6-(4-(((((((S)-4,11-diethyl-4-hydroxy-3,14-dioxo-3,4,12,14-tetrahydro-1H-pyrano [3',4':6,7] indolizino [1,2-b] quinolin-9-yl)oxy)methyl)(2 (methylsulfonyl)ethyl)carbamoyl)oxy)methyl)-2-(2-(3-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-methylpropanamido)acetamido)phenoxy)-3,4,5-trihydroxytetra-hydro-2H-pyran-2-carboxylic acid) as a proof-of-concept. This method is based on immunoprecipitation using magnetic beads and the quantification of albumin-conjugated drug concentration using LC-qTOF/MS in mouse plasma. Finally, the developed method was applied to the in vivo intravenous (IV) mouse pharmacokinetic study of MAC glucuronide phenol-linked SN-38.


Asunto(s)
Albúminas , Inmunoprecipitación , Irinotecán , Cromatografía Líquida con Espectrometría de Masas , Animales , Humanos , Ratones , Albúminas/química , Albúminas/farmacocinética , Glucuronidasa/metabolismo , Glucurónidos/química , Glucurónidos/metabolismo , Inmunoprecipitación/métodos , Irinotecán/sangre , Irinotecán/química , Irinotecán/metabolismo , Irinotecán/farmacocinética , Cromatografía Líquida con Espectrometría de Masas/métodos , Magnetismo , Fenol/química
5.
Invest New Drugs ; 40(5): 1001-1010, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35802288

RESUMEN

Preclinical models suggest anticancer activity of IM156, a novel biguanide mitochondrial protein complex 1 inhibitor of oxidative phosphorylation (OXPHOS). This first-in-human dose-escalation study enrolled patients with refractory advanced solid tumors to determine the maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D). Eligible patients received oral IM156 every other day (QOD) or daily (QD) and were assessed for safety, dose-limiting toxicities (DLTs), pharmacokinetics, and preliminary signals of efficacy. 22 patients with advanced cancers (gastric, n = 8; colorectal, n = 3; ovarian, n = 3; other, n = 8) received IM156 100 to 1,200 mg either QOD or QD. There were no DLTs. However, 1,200 mg QD was not well tolerated due to nausea; 800 mg QD was determined as the RP2D. The most frequent treatment-related AEs (TRAEs) were nausea (n = 15; 68%), diarrhea (n = 10; 46%), emesis (n = 9; 41%), fatigue (n = 4; 18%) and abdominal pain, constipation, and blood lactate increased (n = 2 each; 9%). Grade 3 nausea (n = 3; 14%) was the only grade ≥ 3 TRAE. Plasma exposures increased dose proportionally; mean Day 27 area under the curve (AUC0-24) values were higher following QD administration compared to the respective QOD regimen. Stable disease (SD), observed in 7 (32%) patients (confirmed in 2 [9%]), was the best response. To our knowledge, this is the first phase 1 study of an OXPHOS inhibitor that established a RP2D for further clinical development in cancer. Observed AEs of IM156 were manageable and SD was the best response.


Asunto(s)
Antineoplásicos , Neoplasias , Antineoplásicos/efectos adversos , Biguanidas/uso terapéutico , Relación Dosis-Respuesta a Droga , Humanos , Dosis Máxima Tolerada , Náusea/inducido químicamente , Neoplasias/metabolismo , Fosforilación Oxidativa
6.
Epilepsia ; 63(12): e172-e177, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36239616

RESUMEN

Anti-Hu-associated neurologic autoimmunity most often occurs in the context of small cell lung cancer and typically presents with peripheral neuropathy, cerebellar ataxia, and/or limbic encephalitis. Extra-limbic encephalitis causing seizures is a rare disease manifestation, with only sparse reports in the literature. Herein we present a patient with seizures in anti-Hu-associated extra-limbic encephalitis, and review the literature for other cases to more fully characterize this entity. Among 27 patients we identified, the median age was 46 years (range: 2-69 years) and 18 of 27 (67%) were female. Focal motor seizures were most common, followed by ictal expressive speech difficulty. Seizure semiologies along with neuroimaging findings most frequently suggested the involvement of the peri-Rolandic cortex, more anterior frontal operculum, and insula, although other cortical regions were rarely affected as well. In contrast to other classical paraneoplastic neurologic syndromes, good response to treatment with attainment of seizure-free survival was often reported, although over one-third still died. A propensity for chronic seizures among children indicated the potential to develop autoimmune-associated epilepsy. The predilection for certain extra-limbic regions, as well as the possibility of good response to treatment, may reflect unique disease mechanisms that would benefit from further study.


Asunto(s)
Encefalitis Límbica , Niño , Humanos , Femenino , Persona de Mediana Edad , Masculino , Encefalitis Límbica/diagnóstico , Encefalitis Límbica/diagnóstico por imagen , Convulsiones/etiología
7.
Molecules ; 27(6)2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35335372

RESUMEN

Daporinad (FK866) is one of the highly specific inhibitors of nicotinamide phosphoribosyl transferase (NAMPT) and known to have its unique mechanism of action that induces the tumor cell apoptosis. In this study, a simple and sensitive liquid chromatography-quadrupole-time-of-flight-mass spectrometric (LC-qTOF-MS) assay has been developed for the evaluation of drug metabolism and pharmacokinetics (DMPK) properties of Daporinad in mice. A simple protein precipitation method using acetonitrile (ACN) was used for the sample preparation and the pre-treated samples were separated by a C18 column. The calibration curve was evaluated in the range of 1.02~2220 ng/mL and the quadratic regression (weighted 1/concentration2) was used for the best fit of the curve with a correlation coefficient ≥ 0.99. The qualification run met the acceptance criteria of ±25% accuracy and precision values for QC samples. The dilution integrity was verified for 5, 10 and 30-fold dilution and the accuracy and precision of the dilution QC samples were also satisfactory within ±25% of the nominal values. The stability results indicated that Daporinad was stable for the following conditions: short-term (4 h), long-term (2 weeks), freeze/thaw (three cycles). This qualified method was successfully applied to intravenous (IV) pharmacokinetic (PK) studies of Daporinad in mice at doses of 5, 10 and 30 mg/kg. As a result, it showed a linear PK tendency in the dose range from 5 to 10 mg/kg, but a non-linear PK tendency in the dose of 30 mg/kg. In addition, in vitro and in vivo metabolite identification (Met ID) studies were conducted to understand the PK properties of Daporinad and the results showed that a total of 25 metabolites were identified as ten different types of metabolism in our experimental conditions. In conclusion, the LC-qTOF-MS assay was successfully developed for the quantification of Daporinad in mouse plasma as well as for its in vitro and in vivo metabolite identification.


Asunto(s)
Plasma , Espectrometría de Masas en Tándem , Animales , Calibración , Cromatografía Liquida/métodos , Ratones , Espectrometría de Masas en Tándem/métodos
8.
Molecules ; 27(23)2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36500706

RESUMEN

The purpose of this study is to investigate the difference of in vitro-in vivo correlation of α-amanitin from clearance perspectives as well as to explore the possibility of extra-hepatic metabolism of α-amanitin. First, a liquid chromatography-quadrupole-time-of-flight-mass spectrometric (LC-qTOF-MS) method for α-amanitin in rat plasma was developed and applied to evaluate the in vitro liver microsomal metabolic stability using rat and human liver microsomes and the pharmacokinetics of α-amanitin in rat. The predicted hepatic clearance of α-amanitin in rat liver microsomes was quite low (5.05 mL/min/kg), whereas its in vivo clearance in rat (14.0 mL/min/kg) was close to the borderline between low and moderate clearance. To find out the difference between in vitro and in vivo metabolism, in vitro and in vivo metabolite identification was also conducted. No significant metabolites were identified from the in vivo rat plasma and the major circulating entity in rat plasma was α-amanitin itself. No reactive metabolites such as GSH-adducts were detected either. A glucuronide metabolite was newly identified from the in vitro liver microsomes samples with a trace level. A semi-mass balance study was also conducted to understand the in vivo elimination pathway of α-amanitin and it showed that most α-amanitin was mainly eliminated in urine as intact which implies some unknown transporters in kidney might play a role in the elimination of α-amanitin in rat in vivo. Further studies with transporters in the kidney would be warranted to figure out the in vivo clearance mechanism of α-amanitin.


Asunto(s)
Alfa-Amanitina , Microsomas Hepáticos , Ratas , Humanos , Animales , Alfa-Amanitina/metabolismo , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Microsomas Hepáticos/metabolismo , Plasma , Cromatografía Líquida de Alta Presión/métodos
9.
Molecules ; 26(4)2021 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-33671835

RESUMEN

Sulfasalazine (SAS), an anti-inflammatory drug with potent cysteine/glutamate antiporter system xc-(SXC) inhibition has recently shown beneficial effects in brain-related diseases. Despite many reports related to central nervous system (CNS) effect of SAS, pharmacokinetics (PK) and metabolite identification studies in the brain for SAS were quite limited. The aim of this study was to investigate the pharmacokinetics and metabolite identification of SAS and their distributions in mouse brain. Using in vivo brain exposure studies (neuro PK), the PK parameters of SAS was calculated for plasma as well as brain following intravenous and oral administration at 10 mg/kg and 50 mg/kg in mouse, respectively. In addition, in vivo metabolite identification (MetID) studies of SAS in plasma and brain were also conducted. The concentration of SAS in brain was much lower than that in plasma and only 1.26% of SAS was detected in mouse brain when compared to the SAS concentration in plasma (brain to plasma ratio (%): 1.26). In the MetID study, sulfapyridine (SP), hydroxy-sulfapyridine (SP-OH), and N-acetyl sulfapyridine (Ac-SP) were identified in plasma, whereas only SP and Ac-SP were identified as significant metabolites in brain. As a conclusion, our results suggest that the metabolites of SAS such as SP and Ac-SP might be responsible for the pharmacological effect in brain, not the SAS itself.


Asunto(s)
Encéfalo/metabolismo , Sulfasalazina/análisis , Sulfasalazina/metabolismo , Animales , Masculino , Espectrometría de Masas , Ratones , Ratones Endogámicos ICR , Sulfasalazina/farmacocinética , Factores de Tiempo
10.
Mol Pharm ; 17(4): 1079-1089, 2020 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-32053381

RESUMEN

Ticagrelor (TCG) has been used as an antiplatelet agent for acute coronary syndrome patients. The aim of this research was to establish a population pharmacokinetic/pharmacodynamic (PK/PD) model of TCG and to apply the model for predicting the PD response of the TCG-loaded self-microemulsifying drug delivery system (TCG-SME) in rats. Pure TCG and TCG-SME (2, 5, and 10 mg/kg of TCG) were orally administered to male Sprague-Dawley rats. Plasma samples were collected at scheduled time-points and then analyzed for TCG plasma concentrations and antiplatelet effects. The inhibition of platelet aggregation of TCG was measured as a PD response. The PK profiles of pure TCG and TCG-SME could be well-explained with a two-compartment PK model. The accuracy of the PK model was assessed with a goodness-of-fit plot and conditional weight residual error (CWRES). Also, the visual predictive check was investigated based on the predictions. A population PK/PD model for pure TCG was established as an indirect response Emax model linked to the two-compartment PK model of pure TCG. The PK/PD model proposed a suitable fitting to link the plasma concentration of TCG simultaneously with platelet aggregation. Based on the PK data of TCG-SME, as well as the established PK/PD model of pure TCG, the PD profiles of TCG-SME were simulated. TCG-SME was more effective in inducing the antiplatelet effect than pure TCG at equivalent doses of TCG. The accuracy of the simulation was verified by comparing the simulated PD profile with the profile observed in rats. The observations were close to the model simulations. In addition, the values of CWRES were almost within ±2. In conclusion, the PK/PD modeling approach can provide a way for predicting mathematically the PD responses from PK profiles of other TCG formulations and a conceptual prediction for future clinical assessment.


Asunto(s)
Plaquetas/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/farmacocinética , Ticagrelor/farmacología , Ticagrelor/farmacocinética , Animales , Sistemas de Liberación de Medicamentos/métodos , Masculino , Modelos Biológicos , Agregación Plaquetaria/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
11.
Biomed Chromatogr ; 34(8): e4855, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32304111

RESUMEN

MMAE is a potent antimitotic drug used as payload of an antibody-drug conjugate which shows potent activity in preclinical and clinical studies against a range of lymphomas, leukemia and solid tumors. Liquid chromatography-high resolution mass spectrometric method was developed for the quantification of MMAE and its preclinical pharmacokinetics. The method consisted of protein precipitation using acetonitrile (ACN) for sample preparation and liquid chromatography - quadrupole - time-of-flight - tandem mass spectrometry (LC-qTOF-MS/MS) analysis in the positive ion mode. A quadratic regression (weighted 1/concentration2 ), with an equation y = ax2 + bx + c, was used to fit calibration curves over the concentration range of 1.01-2,200 ng/mL for MMAE. The qualification run met the acceptance criteria of ±25% accuracy and precision values for QC samples. Recovery was 42.84%. The dilution integrity was determined for 5-fold dilution and the accuracy and precision ranged within ±25%. The stability results indicated that MMAE was stable for the following conditions: short-term (4 h), long-term (4 weeks), freeze/thaw (3 cycles) and post-preparative stability (12 h). This qualified method was successfully applied to a pharmacokinetic study of MMAE in rat as a preclinical animal model. The PK results suggest that MMAE has moderate CL and low BA.Also, these results would be helpful in having a comprehensive understanding of the PK characteristics of MMAE and developing ADC in future.


Asunto(s)
Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Oligopéptidos/sangre , Oligopéptidos/farmacocinética , Animales , Modelos Animales de Enfermedad , Inmunoconjugados , Modelos Lineales , Masculino , Oligopéptidos/administración & dosificación , Oligopéptidos/química , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
Molecules ; 25(9)2020 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-32397307

RESUMEN

5-Amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo(4,3-e)-1,2,4-triazolo(1,5-c) pyrimidine (SCH 58261) is one of the new chemical entities that has been developed as an adenosine A2A receptor antagonist. Although SCH 58261 has been reported to be beneficial, there is little information about SCH 58261 from a drug metabolism or pharmacokinetics perspective. This study describes the metabolism and pharmacokinetic properties of SCH 58261 in order to understand its behaviors in vivo. Rats were used as the in vivo model species. First, an LC-MS/MS method was developed for the determination of SCH 58261 in rat plasma. A GastroPlus™ simulation, in vitro microsomal metabolic stability, and bile duct-cannulated studies were also performed to understand its pharmacokinetic profile. The parameter sensitivity analysis of GastroPlus™ was used to examine the factors that influence exposure when the drug is orally administered. The factors are as follows: permeability, systemic clearance, renal clearance, and liver first-pass effect. In vitro microsomal metabolic stability indicates how much the drug is metabolized. The extrapolated hepatic clearance value of SCH 58261 was 39.97 mL/min/kg, indicating that the drug is greatly affected by hepatic metabolism. In vitro microsomal metabolite identification studies revealed that metabolites produce oxidized and ketone-formed metabolites via metabolic enzymes in the liver. The bile duct-cannulated rat study, after oral administration of SCH 58261, showed that a significant amount of the drug was excreted in feces. These results imply that the drug is not absorbed well in the body after oral administration. Taken together, SCH 58261 showed quite a low bioavailability when administered orally and this was likely due to significantly limited absorption, as well as high metabolism in vivo.


Asunto(s)
Antagonistas de Receptores Purinérgicos P1 , Pirimidinas , Espectrometría de Masas en Tándem , Triazoles , Animales , Disponibilidad Biológica , Cromatografía Liquida , Hígado/metabolismo , Masculino , Microsomas Hepáticos/metabolismo , Antagonistas de Receptores Purinérgicos P1/química , Antagonistas de Receptores Purinérgicos P1/farmacocinética , Antagonistas de Receptores Purinérgicos P1/farmacología , Pirimidinas/química , Pirimidinas/farmacocinética , Pirimidinas/farmacología , Ratas , Ratas Sprague-Dawley , Triazoles/química , Triazoles/farmacocinética , Triazoles/farmacología
13.
Molecules ; 25(7)2020 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-32225092

RESUMEN

The novel prenyl transferase-mediated, site-specific, antibody-drug conjugate LCB14-0110 is comprised of a proprietary beta-glucuronide linker and a payload (Monomethyl auristatin F, MMAF, an inhibitor for tubulin polymerization) attached to human epidermal growth factor receptor 2 (HER2)-targeting trastuzumab. A LC-MS/MS method was developed to quantify the antibody-conjugated drug (acDrug) for in vitro linker stability and preclinical pharmacokinetic studies. The method consisted of affinity capture, enzymatic cleavage of acDrug, and LC-MS/MS analysis in the positive ion mode. A quadratic regression (weighted 1/concentration2), with the equation y = ax2 + bx + c, was used to fit calibration curves over the concentration range of 19.17~958.67 ng/mL for acDrug. The qualification run met the acceptance criteria of ±25% accuracy and precision values for quality control (QC) samples. The overall recovery was 42.61%. The dilution integrity was for a series of 5-fold dilutions with accuracy and precision values ranging within ±25%. The stability results indicated that acDrug was stable at all stability test conditions (short-term: 1 day, long-term: 10 months, Freeze/Thaw (F/T): 3 cycles). This qualified method was successfully applied to in vitro linker stability and pharmacokinetic case studies of acDrug in rats.


Asunto(s)
Cromatografía Liquida , Inmunoconjugados/química , Inmunoconjugados/farmacocinética , Neopreno , Espectrometría de Masas en Tándem , Transferasas , Animales , Monitoreo de Drogas , Estabilidad de Medicamentos , Humanos , Estructura Molecular , Neopreno/química , Ratas , Transferasas/química , Trastuzumab/química , Trastuzumab/farmacocinética
14.
Molecules ; 25(5)2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32131453

RESUMEN

Parkinson's disease is one of the most common neurodegenerative diseases. Adenosine regulates the response to other neurotransmitters in the brain regions related to motor function. In the several subtypes of adenosine receptors, especially, adenosine 2A receptors (A2ARs) are involved in neurodegenerative conditions. ZM241385 is one of the selective non-xanthine A2AR antagonists with high affinity in the nanomolar range. This study describes the in vitro and in vivo pharmacokinetic properties of ZM241385 in rats. A liquid chromatography-quadrupole time-of-flight mass spectrometric (LC-qToF MS) method was developed for the determination of ZM241385 in rat plasma. In vivo IV administration studies showed that ZM241385 was rapidly eliminated in rats. However, the result of in vitro metabolic stability studies showed that ZM241385 had moderate clearance, suggesting that there is an extra clearance pathway in addition to hepatic clearance. In addition, in vivo PO administration studies demonstrated that ZM241385 had low exposure in rats. The results of semi-mass balance studies and the in silico PBPK modeling studies suggested that the low bioavailability of ZM241385 after oral administration in rats was due to the metabolism and by liver, kidney, and gut.


Asunto(s)
Antagonistas del Receptor de Adenosina A2 , Simulación por Computador , Triazinas , Triazoles , Antagonistas del Receptor de Adenosina A2/farmacocinética , Antagonistas del Receptor de Adenosina A2/farmacología , Animales , Masculino , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , Ratas , Ratas Sprague-Dawley , Receptor de Adenosina A2A/metabolismo , Triazinas/farmacocinética , Triazinas/farmacología , Triazoles/farmacocinética , Triazoles/farmacología
15.
N Engl J Med ; 375(8): 730-9, 2016 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-27557301

RESUMEN

BACKGROUND: Uncontrolled pilot studies have suggested the efficacy of focused ultrasound thalamotomy with magnetic resonance imaging (MRI) guidance for the treatment of essential tremor. METHODS: We enrolled patients with moderate-to-severe essential tremor that had not responded to at least two trials of medical therapy and randomly assigned them in a 3:1 ratio to undergo unilateral focused ultrasound thalamotomy or a sham procedure. The Clinical Rating Scale for Tremor and the Quality of Life in Essential Tremor Questionnaire were administered at baseline and at 1, 3, 6, and 12 months. Tremor assessments were videotaped and rated by an independent group of neurologists who were unaware of the treatment assignments. The primary outcome was the between-group difference in the change from baseline to 3 months in hand tremor, rated on a 32-point scale (with higher scores indicating more severe tremor). After 3 months, patients in the sham-procedure group could cross over to active treatment (the open-label extension cohort). RESULTS: Seventy-six patients were included in the analysis. Hand-tremor scores improved more after focused ultrasound thalamotomy (from 18.1 points at baseline to 9.6 at 3 months) than after the sham procedure (from 16.0 to 15.8 points); the between-group difference in the mean change was 8.3 points (95% confidence interval [CI], 5.9 to 10.7; P<0.001). The improvement in the thalamotomy group was maintained at 12 months (change from baseline, 7.2 points; 95% CI, 6.1 to 8.3). Secondary outcome measures assessing disability and quality of life also improved with active treatment (the blinded thalamotomy cohort)as compared with the sham procedure (P<0.001 for both comparisons). Adverse events in the thalamotomy group included gait disturbance in 36% of patients and paresthesias or numbness in 38%; these adverse events persisted at 12 months in 9% and 14% of patients, respectively. CONCLUSIONS: MRI-guided focused ultrasound thalamotomy reduced hand tremor in patients with essential tremor. Side effects included sensory and gait disturbances. (Funded by InSightec and others; ClinicalTrials.gov number, NCT01827904.).


Asunto(s)
Temblor Esencial/terapia , Tálamo/cirugía , Terapia por Ultrasonido , Actividades Cotidianas , Anciano , Método Doble Ciego , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Calidad de Vida , Terapia por Ultrasonido/efectos adversos , Terapia por Ultrasonido/métodos , Ultrasonografía Intervencional
17.
Molecules ; 24(15)2019 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-31362431

RESUMEN

A simple liquid chromatography-quadrupole-time-of-flight-mass spectrometric assay (LC-TOF-MS/MS) has been developed for the evaluation of metabolism and pharmacokinetic (PK) characteristics of monomethyl auristatin F (MMAF) in rat, which is being used as a payload for antibody-drug conjugates. LC-TOF-MS/MS method was qualified for the quantification of MMAF in rat plasma. The calibration curves were acceptable over the concentration range from 3.02 to 2200 ng/mL using quadratic regression. MMAF was stable in various conditions. There were no significant matrix effects between rat and other preclinical species. The PK studies showed that the bioavailability of MMAF was 0% with high clearance. Additionally, the metabolite profiling studies, in vitro/in vivo, were performed. Seven metabolites for MMAF were tentatively identified in liver microsome. The major metabolic pathway was demethylation, which was one of the metabolic pathways predicted by MedChem Designer. Therefore, these results will be helpful to understand the PK, catabolism, and metabolism behavior of MMAF comprehensively when developing antibody-drug conjugates (ADCs) in the future.


Asunto(s)
Cromatografía Liquida , Metabolómica , Oligopéptidos/farmacocinética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Animales , Biomarcadores , Cromatografía Liquida/métodos , Monitoreo de Drogas , Humanos , Masculino , Redes y Vías Metabólicas , Metabolómica/métodos , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Oligopéptidos/química , Oligopéptidos/metabolismo , Ratas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
18.
Molecules ; 24(7)2019 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-30987056

RESUMEN

Tozadenant is one of the selective adenosine A2a receptor antagonists with a potential to be a new Parkinson's disease (PD) therapeutic drug. In this study, a liquid chromatography-mass spectrometry based bioanalytical method was qualified and applied for the quantitative analysis of tozadenant in rat plasma. A good calibration curve was observed in the range from 1.01 to 2200 ng/mL for tozadenant using a quadratic regression. In vitro and preclinical in vivo pharmacokinetic (PK) properties of tozadenant were studied through the developed bioanalytical methods, and human PK profiles were predicted using physiologically based pharmacokinetic (PBPK) modeling based on these values. The PBPK model was initially optimized using in vitro and in vivo PK data obtained by intravenous administration at a dose of 1 mg/kg in rats. Other in vivo PK data in rats were used to validate the PBPK model. The human PK of tozadenant after oral administration at a dose of 240 mg was simulated by using an optimized and validated PBPK model. The predicted human PK parameters and profiles were similar to the observed clinical data. As a result, optimized PBPK model could reasonably predict the PK in human.


Asunto(s)
Benzotiazoles/sangre , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Antagonistas del Receptor de Adenosina A2 , Animales , Benzotiazoles/farmacocinética , Ratas , Verapamilo/sangre , Verapamilo/farmacocinética
19.
Ann Oncol ; 29(8): 1843-1852, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30010756

RESUMEN

Background: Bevacizumab is a recombinant humanised monoclonal antibody to vascular endothelial growth factor shown to improve survival in advanced solid cancers. We evaluated the role of adjuvant bevacizumab in melanoma patients at high risk of recurrence. Patients and methods: Patients with resected AJCC stage IIB, IIC and III cutaneous melanoma were randomised to receive either adjuvant bevacizumab (7.5 mg/kg i.v. 3 weekly for 1 year) or standard observation. The primary end point was detection of an 8% difference in 5-year overall survival (OS) rate; secondary end points included disease-free interval (DFI) and distant metastasis-free interval (DMFI). Tumour and blood were analysed for prognostic and predictive markers. Results: Patients (n=1343) recruited between 2007 and 2012 were predominantly stage III (73%), with median age 56 years (range 18-88 years). With 6.4-year median follow-up, 515 (38%) patients had died [254 (38%) bevacizumab; 261 (39%) observation]; 707 (53%) patients had disease recurrence [336 (50%) bevacizumab, 371 (55%) observation]. OS at 5 years was 64% for both groups [hazard ratio (HR) 0.98; 95% confidence interval (CI) 0.82-1.16, P = 0.78). At 5 years, 51% were disease free on bevacizumab versus 45% on observation (HR 0.85; 95% CI 0.74-0.99, P = 0.03), 58% were distant metastasis free on bevacizumab versus 54% on observation (HR 0.91; 95% CI 0.78-1.07, P = 0.25). Forty four percent of 682 melanomas assessed had a BRAFV600 mutation. In the observation arm, BRAF mutant patients had a trend towards poorer OS compared with BRAF wild-type patients (P = 0.06). BRAF mutation positivity trended towards better OS with bevacizumab (P = 0.21). Conclusions: Adjuvant bevacizumab after resection of high-risk melanoma improves DFI, but not OS. BRAF mutation status may predict for poorer OS untreated and potential benefit from bevacizumab. Clinical Trial Information: ISRCTN 81261306; EudraCT Number: 2006-005505-64.


Asunto(s)
Bevacizumab/administración & dosificación , Melanoma/terapia , Recurrencia Local de Neoplasia/prevención & control , Neoplasias Cutáneas/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante/métodos , Procedimientos Quirúrgicos Dermatologicos , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Melanoma/mortalidad , Melanoma/patología , Persona de Mediana Edad , Mutación , Recurrencia Local de Neoplasia/epidemiología , Estadificación de Neoplasias , Proteínas Proto-Oncogénicas B-raf/genética , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/patología , Análisis de Supervivencia , Factores de Tiempo , Espera Vigilante , Adulto Joven
20.
Haemophilia ; 24(3): 414-419, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29405496

RESUMEN

INTRODUCTION: Although clinical trials have demonstrated extended half-life (EHL) VIII and IX fusion proteins to be safe and efficacious in patients with haemophilia A and B, studies on real-world clinical application have not been performed. AIM: To retrospectively examine the real-world experience of rFVIII Fc and rFIX Fc in patients. METHODS: A retrospective review of existing medical records of patients with haemophilia A or haemophilia B who had been prescribed rFVIII Fc or rFIX Fc was conducted from the Children's Hospital Los Angeles Haemostasis and Thrombosis Centre database. RESULTS: A total of 36 male subjects enroled in the study (17 patients with haemophilia A and 19 patients with haemophilia B; 0-18 years of age, N = 27; >18 years of age, N = 9). Patients had a reduction of their ABR and AJBR following initiation of EHL factors. For patients with haemophilia A, the ABR and ABJR fell from 2.3 and 1.8 to 1.3 and 0.71, respectively. For patients with haemophilia B, the ABR and ABJR fell from 2.5 and 2.1 to 0.82 and 0.37, respectively. Five of 36 patients reverted from EHL back to standard half-life (SHL) factor treatment. Overall, treatment with EHL factors reduced factor consumption by nearly half compared to treatment with SHL factors in patients with haemophilia B. CONCLUSION: This study demonstrates the largely successful transition of 36 patients from SHL to EHL factor products.


Asunto(s)
Factor IX/uso terapéutico , Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Hemofilia B/tratamiento farmacológico , Proteínas Recombinantes de Fusión/uso terapéutico , Adolescente , Niño , Preescolar , Femenino , Hemofilia A/complicaciones , Hemofilia B/complicaciones , Hemorragia/complicaciones , Hemorragia/prevención & control , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Adulto Joven
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