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1.
Clin Exp Med ; 23(7): 3883-3893, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37395895

RESUMO

Metabolic reprogramming in breast cancer involves changes in steroid hormone synthesis and metabolism. Alterations in estrogen levels in both breast tissue and blood may influence carcinogenesis, breast cancer growth, and response to therapy. Our aim was to examine whether serum steroid hormone concentrations could predict the risk of recurrence and treatment-related fatigue in patients with breast cancer. This study included 66 postmenopausal patients with estrogen receptor-positive breast cancer who underwent surgery, radiotherapy, and adjuvant endocrine treatment. Serum samples were collected at six different time points [before the start of radiotherapy (as baseline), immediately after radiotherapy, and then 3, 6, 12 months, and 7-12 years after radiotherapy]. Serum concentrations of eight steroid hormones (cortisol, cortisone, 17α-hydroxyprogesterone, 17ß-estradiol, estrone, androstenedione, testosterone, and progesterone) were measured using a liquid chromatography-tandem mass spectrometry-based method. Breast cancer recurrence was defined as clinically proven relapse/metastatic breast cancer or breast cancer-related death. Fatigue was assessed with the QLQ-C30 questionnaire. Serum steroid hormone concentrations measured before and immediately after radiotherapy differed between relapse and relapse-free patients [(accuracy 68.1%, p = 0.02, and 63.2%, p = 0.03, respectively, partial least squares discriminant analysis (PLS-DA)]. Baseline cortisol levels were lower in patients who relapsed than in those who did not (p < 0.05). The Kaplan-Meier analysis showed that patients with high baseline concentrations of cortisol (≥ median) had a significantly lower risk of breast cancer recurrence than patients with low cortisol levels (

Assuntos
Neoplasias da Mama , Cortisona , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Cortisona/análise , Hidrocortisona/análise , Recidiva Local de Neoplasia , Esteroides , Recidiva
2.
Eur J Clin Pharmacol ; 77(12): 1901-1908, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34327552

RESUMO

PURPOSE: Remifentanil has been shown to increase the bioavailability of nasally administered naloxone. The aim of this study was to explore the nature of this observation. METHODS: We analysed samples from three pharmacokinetic studies to determine the serum concentrations of naloxone-3-glucuronide (N3G), the main metabolite of naloxone, with or without exposure to remifentanil. To enable direct comparison of the three studies, the data are presented as metabolic ratios (ratio of metabolite to mother substance, N3G/naloxone) and dose-corrected values of the area under the curve and maximum concentration (Cmax). RESULTS: Under remifentanil exposure, the time to maximum concentration (Tmax) for N3G was significantly higher for intranasal administration of 71 min compared to intramuscular administration of 40 min. The dose-corrected Cmax of N3G after intranasal administration of naloxone under remifentanil exposure was significantly lower (4.5 ng/mL) than in subjects not exposed to remifentanil (7.8-8.4 ng/mL). The metabolic ratios after intranasal administration rose quickly after 30-90 min and were 2-3 times higher at 360 min compared to intravenous and intramuscular administration. Remifentanil exposure resulted in a much slower increase of the N3G/naloxone ratio after intranasal administration compared to intranasal administration with the absence of remifentanil. After remifentanil infusion was discontinued, this effect gradually diminished. From 240 min there was no significant difference between the ratios observed after intranasal naloxone administration. CONCLUSION: Remifentanil increases the bioavailability of naloxone after nasal administration by reducing the pre-systemic metabolism of the swallowed part of the nasal dose.


Assuntos
Analgésicos Opioides/farmacologia , Naloxona/análogos & derivados , Naloxona/farmacocinética , Antagonistas de Entorpecentes/farmacocinética , Remifentanil/farmacologia , Administração Intranasal , Área Sob a Curva , Relação Dose-Resposta a Droga , Voluntários Saudáveis , Humanos , Injeções Intramusculares , Taxa de Depuração Metabólica , Naloxona/administração & dosagem , Naloxona/sangue , Antagonistas de Entorpecentes/administração & dosagem
3.
Tidsskr Nor Laegeforen ; 139(13)2019 Sep 24.
Artigo em Norueguês, Inglês | MEDLINE | ID: mdl-31556537

RESUMO

BACKGROUND: Bystander administration with naloxone nasal spray can prevent deaths from opioid overdose. To achieve optimal nasal absorption of naloxone, the spray must be administered at low volume with high concentration of the drug. The study aimed to investigate the bioavailability and absorption pattern for a new naloxone nasal spray. MATERIAL AND METHOD: In an open, randomised, two-way crossover study undertaken in five healthy men, naloxone 2 mg (20 mg/ml) in nasal spray was compared with 1 mg intravenously administered naloxone. A total of 15 blood samples were taken over a period of six hours after administration. The drug concentration was determined using liquid chromatography tandem-mass spectrometry. Pharmacokinetic variables were calculated using non-compartmental analysis. RESULTS: Bioavailability for intranasal naloxone was 47 % (minimum-maximum values 24-66 %). Maximum concentration (Cmax) was 4.2 (1.5-7.1) ng/ml, and this was achieved (Tmax ) after 16 (5-25) minutes. INTERPRETATION: The nasal spray resulted in a rapid systemic absorption with higher serum concentrations than intravenous naloxone 10-240 minutes after intake. The pilot study indicated that the highly concentrated nasal spray may provide a therapeutic dose of naloxone with a single spray actuation. The findings led to further commercial development of the medication.


Assuntos
Antídotos , Naloxona , Sprays Nasais , Administração Intravenosa , Adulto , Analgésicos Opioides/intoxicação , Antídotos/administração & dosagem , Antídotos/farmacocinética , Disponibilidade Biológica , Estudos Cross-Over , Overdose de Drogas/tratamento farmacológico , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Naloxona/administração & dosagem , Naloxona/farmacocinética , Projetos Piloto , Espectrometria de Massas em Tandem , Adulto Jovem
4.
Eur J Clin Pharmacol ; 74(12): 1547-1553, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30143830

RESUMO

PURPOSE: Pharmacodynamic studies of naloxone require opioid agonism. Steady state condition may be achieved by remifentanil TCI (target controlled infusion). Opioid agonism can be measured by pupillometry. It is not known whether there are arteriovenous concentration differences for naloxone. The aim was thus to further develop a model for studying pharmacokinetic/pharmacodynamic aspects of naloxone and to explore whether a significant arteriovenous concentration difference for naloxone in humans was present. METHODS: Relevant authorities approved this study. Healthy volunteers (n = 12) were given 1.0 mg intravenous (IV) naloxone after steady state opioid agonism was obtained by TCI of remifentanil (1.3 ng/ml). Opioid effect was measured by pupillometry. Arterial and venous samples were collected simultaneously before and for 2 h after naloxone administration for quantification of naloxone and remifentanil. RESULTS: Arterial remifentanil was in steady state at 12 min. One milligram IV naloxone reversed the effect of remifentanil to 93% of pre-opioid pupil-size within 4 min. The estimated duration of antagonism was 118 min. At that time, the concentration of naloxone was 0.51 ng/ml. The time course of arterial and venous serum concentrations for naloxone was similar, although arterial AUC (area under the curve) was slightly lower (94%) than the venous AUC (p = 0.03). There were no serious adverse events. CONCLUSION: Onset of reversal by IV naloxone was rapid and lasted 118 min. The minimum effective concentration was 0.5 ng/ml. Using TCI remifentanil to obtain a steady-state opioid agonism may be a useful tool to compare new naloxone products.


Assuntos
Analgésicos Opioides/farmacologia , Naloxona/farmacocinética , Antagonistas de Entorpecentes/farmacocinética , Remifentanil/farmacologia , Adulto , Artérias/metabolismo , Interações Medicamentosas , Feminino , Voluntários Saudáveis , Humanos , Infusões Intravenosas , Masculino , Naloxona/administração & dosagem , Antagonistas de Entorpecentes/administração & dosagem , Pupila/efeitos dos fármacos , Veias/metabolismo , Adulto Jovem
5.
Eur J Clin Pharmacol ; 74(7): 873-883, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29568976

RESUMO

PURPOSE: This study aimed to develop a model for pharmacodynamic and pharmacokinetic studies of naloxone antagonism under steady-state opioid agonism and to compare a high-concentration/low-volume intranasal naloxone formulation 8 mg/ml to intramuscular 0.8 mg. METHODS: Two-way crossover in 12 healthy volunteers receiving naloxone while receiving remifentanil by a target-controlled infusion for 102 min. The group were subdivided into three different doses of remifentanil. Blood samples for serum naloxone concentrations, pupillometry and heat pain threshold were measured. RESULTS: The relative bioavailability of intranasal to intramuscular naloxone was 0.75. Pupillometry showed difference in antagonism; the effect was significant in the data set as a whole (p < 0.001) and in all three subgroups (p < 0.02-p < 0.001). Heat pain threshold showed no statistical difference. CONCLUSIONS: A target-controlled infusion of remifentanil provides good conditions for studying the pharmacodynamics of naloxone, and pupillometry was a better modality than heat pain threshold. Intranasal naloxone 0.8 mg is inferior for a similar dose intramuscular. Our design may help to bridge the gap between studies in healthy volunteers and the patient population in need of naloxone for opioid overdose. TRIAL REGISTRATION: clinicaltrials.gov : NCT02307721.


Assuntos
Analgésicos Opioides/administração & dosagem , Modelos Biológicos , Naloxona/administração & dosagem , Antagonistas de Entorpecentes/administração & dosagem , Piperidinas/administração & dosagem , Administração Intranasal , Adulto , Analgésicos Opioides/farmacologia , Estudos Cross-Over , Feminino , Voluntários Saudáveis , Humanos , Injeções Intramusculares , Masculino , Miose/induzido quimicamente , Miose/tratamento farmacológico , Naloxona/sangue , Naloxona/farmacocinética , Naloxona/farmacologia , Antagonistas de Entorpecentes/sangue , Antagonistas de Entorpecentes/farmacocinética , Antagonistas de Entorpecentes/farmacologia , Dor/tratamento farmacológico , Piperidinas/farmacologia , Pupila/efeitos dos fármacos , Remifentanil , Adulto Jovem
6.
Eur J Clin Pharmacol ; 73(5): 555-562, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28144724

RESUMO

PURPOSE: Nasal naloxone is wanted for bystander administration in opioid overdose and as a needle-free alternative for emergency medical personnel. Epidemiologic studies have indicated a therapeutic effect of bystander administration of low-concentration/high-volume formulations. The objective for this study was to describe the nasal pharmacokinetics of a new high-concentration/low-volume nasal formulation of naloxone. METHODS: This was an open, randomized triple crossover trial in healthy, human volunteers (n = 12) where two doses of nasal naloxone (0.8 and 1.6 mg) and one intravenous dose (1.0 mg) were compared. Fifteen serum samples were collected before and until 6 h after naloxone administration. Quantification of naloxone was performed by a validated liquid chromatography-tandem mass spectrometry method. RESULTS: Bioavailability was 0.54 (0.45-0.63) for the 0.8 mg and 0.52 (0.37-0.67) for the 1.6 mg nasal naloxone formulation. Maximum concentration levels (C max) were 1.45 ng/ml (1.07-1.84) for 0.8 mg and 2.57 ng/ml (1.49-3.66) for the 1.6 mg. Time to maximum concentrations (T max) were reached at 17.9 min (11.4-24.5) and 18.6 min (14.4-22.9) for the 0.8 mg and the 1.6 mg doses, respectively. CONCLUSION: This nasal naloxone formulation had a rapid, systemic uptake and higher bioavailability than naloxone formulations not designed for IN use. This indicates that an optimized high-concentration/low-volume nasal spray formulation may deliver a therapeutic dose. The 1.6 mg nasal dose provided serum concentrations that surpassed those of 1.0 mg IV after 15-20 min and stayed above for the rest of the study period.


Assuntos
Naloxona/farmacocinética , Antagonistas de Entorpecentes/farmacocinética , Administração Intranasal , Adolescente , Adulto , Área Sob a Curva , Disponibilidade Biológica , Cromatografia Líquida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Naloxona/administração & dosagem , Naloxona/efeitos adversos , Naloxona/sangue , Antagonistas de Entorpecentes/administração & dosagem , Antagonistas de Entorpecentes/efeitos adversos , Antagonistas de Entorpecentes/sangue , Espectrometria de Massas em Tandem , Adulto Jovem
7.
Scand Cardiovasc J ; 40(5): 291-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17012140

RESUMO

OBJECTIVE: To investigate oxidative stress and myocardial injury at different stages of coronary artery bypass grafting (CABG). DESIGN: Twenty patients underwent CABG with use of cardiopulmonary bypass (CPB) and with intermittent sampling of plasma and urine. Main markers were: 8-iso-PGF2alpha (oxidative stress); troponin T (myocardial injury); and 15-keto-dihydro-PGF2alpha and hsCRP (inflammation). RESULTS: Plasma 8-iso-PGF2alpha increased after start of surgery, but there was no further rise during CPB or after aortic cross-clamp release and no significant myocardial arterio-venous differences. An increase in troponin T was seen early after the operation, but no relationship was established between 8-iso-PGF2alpha and troponin T. 8-iso-PGF2alpha levels were elevated by preoperative withdrawal of acetylsalicylic acid (ASA) but reduced by intraoperative use of heparin. 15-keto-dihydro-PGF2alpha was elevated during operation and hsCRP following operation. CONCLUSIONS: In the present study oxidative stress was multifactorial in origin with main impacts from surgical trauma, less from CPB and little if any from myocardial ischemia-reperfusion events. In addition, cardiovascular drugs in common use like ASA and heparin seemed to influence the pro- and antioxidant balance, a finding that has to be confirmed in future studies.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/métodos , Estresse Oxidativo , Idoso , Biomarcadores , Dinoprosta/análogos & derivados , Dinoprosta/análise , Tratamento Farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reperfusão Miocárdica , Estresse Oxidativo/efeitos dos fármacos , Troponina T/análise
8.
Free Radic Res ; 39(6): 629-36, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16036341

RESUMO

BACKGROUND: In acute myocardial infarction (AMI) treated with percutaneous coronary intervention (PCI), myocardial injury results from complex processes during both ischemia and reperfusion. Release of reactive oxygen species (ROS) may contribute to the accumulated myocardial damage. AIMS: To examine by frequent sampling of peripheral blood oxidative stress and early inflammation in patients undergoing primary PCI for AMI. Secondly, to assess whether a correlation exists between these parameters and the extent of myocardial damage. METHODS: Sixteen patients undergoing primary PCI within 6 h of AMI onset were included. Peripheral blood was sampled at start of procedure (t0) and repeatedly over 24 h following reperfusion. Main plasma analyses were: 8-iso-PGF2alpha (oxidative stress), 15-keto-dihydro-PGF2alpha (cyclooxygenase-mediated inflammation); and troponin-T (myocardial injury). Additional analyses included: total antioxidant status (TAS); vitamins; hsCRP and lipids. RESULTS: 8-Iso-PGF2alpha increased following restoration of blood flow, returned to t0 values after 3 h and was reduced below t0 the following day. TAS decreased significantly from t0 to the next day. There was no significant correlation between 8-iso-PGF2alpha and troponin T values. 15-Keto-dihydro-PGF2alpha was elevated during the first hour. There was a major rise in hsCRP after 24 h. CONCLUSION: Following reperfusion by primary PCI in AMI, oxidative stress and an inflammatory response are induced immediately. A rise in 8-iso-PGF2a during ischemia indicate that ROS generation may also take place during severely reduced coronary blood flow and hypoxia. No direct relationship between 8-iso-PGF2alpha or 15-keto-dihydro-PGF2alpha and troponin T was evident. The present study adds to the increasingly complex pathophysiological roles of ROS acting both as signal molecules and as mediators of tissue injury.


Assuntos
Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Estresse Oxidativo , Doença Aguda , Adulto , Idoso , Vasos Coronários/metabolismo , Dinoprosta/química , Dinoprosta/metabolismo , Feminino , Humanos , Hidroxilação , Inflamação/metabolismo , Metabolismo dos Lipídeos , Masculino , Pessoa de Meia-Idade , Albumina Sérica/metabolismo , Troponina T/metabolismo
9.
Magn Reson Med ; 52(3): 506-14, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15334568

RESUMO

The efficacy of manganese ions (Mn2+) as intracellular (ic) contrast agents was assessed in rat myocardium. T1 and T2 and Mn content were measured in ventricular tissue excised from isolated perfused hearts in which a 5-min wash-in with 0, 30, 100, 300, or 1000 microM of Mn dipyridoxyl diphosphate (MnDPDP) was followed by a 15-min wash-out to remove extracellular (ec) Mn2+. An inversion recovery (IR) analysis at 20 MHz revealed two T1 components: an ic and short T1-1 (650-251 ms), and an ec and longer T1-2 (2712-1042 ms). Intensities were about 68% and 32%, respectively. Tissue Mn content correlated particularly well with ic R1-1. A two-site water-exchange analysis of T1 data documented slow water exchange with ic and ec lifetimes of 11.3 s and 7.5 s, respectively, and no differences between apparent and intrinsic relaxation parameters. Ic relaxivity induced by Mn2+ ions in ic water was as high as 56 (s mM)(-1), about 8 times and 36 times higher than with Mn2+ aqua ions and MnDPDP, respectively, in vitro. This value is as high as any reported to date for any synthetic protein-bound metal chelate. The increased rotational correlation time (tauR) between proton and electron (Mn2+) spins, and maintained inner-sphere water access, might make ic Mn2+ ions and Mn2+ -ion-releasing contrast media surprisingly effective for T1-weighted imaging.


Assuntos
Meios de Contraste/farmacocinética , Manganês/farmacocinética , Miocárdio/metabolismo , Análise de Variância , Animais , Meios de Contraste/administração & dosagem , Liofilização , Coração/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Técnicas In Vitro , Análise dos Mínimos Quadrados , Masculino , Manganês/administração & dosagem , Ratos , Ratos Wistar
10.
Free Radic Res ; 38(5): 517-25, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15293560

RESUMO

The role of oxidative stress in clinical cardiology is still controversial. The aims of the present study were to examine if minor ischaemic episodes as may occur during elective percutaneous coronary intervention (PCI) induce oxidative stress and, eventually, if oxygen stress correlates with myocardial injury. Thirty eight and nine patients underwent PCI and diagnostic coronary angiography, respectively. Peripheral blood was sampled at different time points for plasma analyses of: 8-iso-PGF2alpha (free radical-mediated oxidative stress); 15-keto-dihydro-PGF2alpha (cyclooxygenase-mediated inflammation); troponin-T (myocardial injury); hsCRP, vitamin A and vitamin E; and, total antioxidants status (TAS). In both groups 8-iso-PGF2alpha increased transiently by approximately 80% (p < 0.001) during the procedure. There was a minor troponin-T release (p < 0.001) after PCI, but no correlation with 8-iso-PGF2alpha. Troponin-T did not increase after angiography. 15-keto-dihydro-PGF2alpha decreased by 50% after ended procedure, but increased by 100% after 24 h compared to baseline. hsCRP increased significantly (p < 0.001) from baseline to the next day in the PCI-group, but not in the angiography group. Vitamins and TAS decreased slightly after the procedures. It is concluded that a moderate oxidative stress was induced by both elective PCI and coronary angiography but that no correlation was found between oxidative stress and myocardial injury in this setting. This indicates that other mechanisms than ischaemia-reperfusion episodes caused an elevation in plasma isoprostane such like the injury at a vascular site mutual for both procedures. A secondary finding from the study was elevated markers of early inflammatory response, not only after PCI, but also after angiography.


Assuntos
Angioplastia Coronária com Balão , Biomarcadores/sangue , Dinoprosta/análogos & derivados , Infarto do Miocárdio/terapia , Estresse Oxidativo , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão a Laser , Antioxidantes/metabolismo , Proteína C-Reativa/metabolismo , Angiografia Coronária , Dinoprosta/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Troponina T/sangue , Vitamina A/sangue , Vitamina E/sangue
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