RESUMO
BACKGROUND: The concentration of MTX in blood is often measured quickly and easily by immunoassays. Thus, immunoassays may facilitate the easy determination of the concentration of MTX in the cerebrospinal fluid (CSF). In this study, we measured methotrexate (MTX) concentrations in the CSF using a high-performance liquid chromatography (HPLC) method intended for analyzing CSF matrices and a chemiluminescence immunoassay (CLIA) method intended for assessing serum and plasma matrices and verified the differences in the results of the two methods. METHODS: HPLC analysis for MTX in the CSF was performed using a Prominence UFLC system with a C18 column. The HPLC method was validated in accordance with the 2018 FDA guideline. The CLIA method was performed using an ARCHITECT i1000SR system intended for serum and plasma matrices. A total of 47 CSF samples (14 clinical and 33 spiked specimens) were analyzed using the two methods. RESULTS: The HPLC method passed the validation criteria. The concentration of MTX in the same sample, determined using the HPLC and CLIA methods, differed proportionally; the percent difference in the concentrations averaged -23.0% (95% confidence interval: -36.9% to -9.1%) as revealed by the Bland-Altman plot. The relationship between the measured values, evaluated using the Passing-Bablok regression, was as follows: HPLC = 1.205 × CLIA - 0.024. CONCLUSION: The equation deduced in this study can be used to correct the concentration of MTX measured using the CLIA method.
Assuntos
Imunoensaio/métodos , Metotrexato/líquido cefalorraquidiano , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Limite de Detecção , Medições Luminescentes , Reprodutibilidade dos TestesRESUMO
We examined the role of aldosterone-sensitive neurons in the nucleus tractus solitarius (NTS) in the arterial baroreceptor reflex (baroreflex) function. Baroreflex sensitivity was induced by phenylephrine in high sodium-loaded rats and was significantly reduced. This baroreflex sensitivity was reversed by microinjection of the mineralocorticoid receptor (MR) antagonist eplerenone into the NTS. 11beta-Hydroxysteroid dehydrogenase type 2 neurons and MR were also identified in the NTS. These data suggest that the aldosterone-sensitive neurons in the NTS may have an important role in baroreflex function.
Assuntos
Aldosterona/farmacologia , Neurônios/efeitos dos fármacos , Pressorreceptores/efeitos dos fármacos , Sódio/administração & dosagem , Núcleo Solitário/efeitos dos fármacos , Animais , Ratos , Núcleo Solitário/citologiaRESUMO
Objective: Tacrolimus is administered to patients undergoing haematopoietic stem cell transplantation (HSCT) as prophylaxis for graft-versus-host disease. As a high blood tacrolimus concentration within a narrow therapeutic range must be maintained after HSCT, therapeutic drug monitoring (TDM) is necessary. We investigated the correlation between blood tacrolimus concentration and blood cell count in HSCT patients to assess how changes in blood cell count affect tacrolimus TDM. Methods: A retrospective analysis was performed for 24 patients who underwent allogeneic HSCT and received tacrolimus. The correlation between variations in blood tacrolimus concentration and blood cell count was evaluated for three consecutive weeks, starting 1 week after HSCT. Results: Variations in blood tacrolimus concentration were significantly correlated with variations in red blood cell (RBC) count, haemoglobin level and haematocrit value, but not with variations in white blood cell or platelet counts. Further, the above variations were significantly correlated in patients undergoing cord blood transplantation and peripheral blood stem cell transplantation, but not in those undergoing bone marrow transplantation. Conclusions: These findings demonstrate that RBC count is associated with variations in blood tacrolimus concentration, with the relevance of this association depending on the source of transfused stem cells. Thus, variations in RBC count might be useful for tacrolimus TDM.
Assuntos
Contagem de Células Sanguíneas/métodos , Monitoramento de Medicamentos/métodos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Imunossupressores/sangue , Tacrolimo/sangue , Adulto , Idoso , Feminino , Doença Enxerto-Hospedeiro/sangue , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tacrolimo/uso terapêutico , Transplante HomólogoRESUMO
Helicobacter cinaedi is an emerging pathogen causing bacteraemia and cellulitis. Nosocomial transmission of this microbe has been described, but detailed molecular-epidemiological analyses have not been performed. Here, we describe the results of a multi-step genome-wide phylogenetic analysis of a suspected intra-hospital outbreak of H. cinaedi that occurred in a hospital in Japan. The outbreak was recognized by the infectious control team (ICT) of the hospital as a sudden increase in H. cinaedi bacteraemia. ICT defined this outbreak case based on 16S rRNA sequence data and epidemiological information, but were unable to determine the source and route of the infections. We therefore re-investigated this case using whole-genome sequencing (WGS). We first performed a species-wide analysis using publicly available genome sequences to understand the level of genomic diversity of this under-studied species. The clusters identified were then separately analysed using the genome sequence of a representative strain in each cluster as a reference. These analyses provided a high-level phylogenetic resolution of each cluster, identified a confident set of outbreak isolates, and discriminated them from other closely related but distinct clones, which were locally circulating and invaded the hospital during the same period. By considering the epidemiological data, possible strain transmission chains were inferred, which highlighted the role of asymptomatic carriers or environmental contamination. The emergence of a subclone with increased resistance to fluoroquinolones in the outbreak was also recognized. Our results demonstrate the impact of the use of a closely related genome as a reference to maximize the power of WGS.
Assuntos
Bacteriemia , Surtos de Doenças , Genômica , Infecções por Helicobacter , Helicobacter/genética , Filogenia , Bacteriemia/epidemiologia , Bacteriemia/genética , Feminino , Helicobacter/patogenicidade , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/genética , Humanos , Japão/epidemiologia , Masculino , Sequenciamento Completo do GenomaRESUMO
In this study, we examined the effects of an intracerebroventricular (i.c.v.) administration of prostaglandin E2 (PGE2) and of selective agonists for PGE2 receptor subtypes, EP1, EP2, EP3 and EP4, on central cardiovascular regulation and renal sympathetic nerve activity (RSNA) in urethane-anesthetized rats. The central administration of PGE2 (0.01-1.0 nmol) resulted in increases in blood pressure, heart rate (HR) and RSNA in a dose-dependent manner. Cardiovascular responses to PGE2 (0.5 nmol, i.c.v.) were attenuated by pretreatment with ganglionic and adrenoceptor blocking agents, but not with SC-19220 (20 nmol, i.c.v.), an EP1 receptor antagonist. An i.c.v. administration of the EP3 agonist ONO-AE-248 (50.0 nmol) resulted in an increase in RSNA with pressor and tachycardia responses, while administration of the EP2 agonist ONO-AE1-259 and the EP4 agonist ONO-AE1-329 caused transient hypotension and slight increases in HR and RSNA. The administration of the selective EP1 agonist ONO-DI-004 showed no effect. These results suggest that the central PGE2-induced activation of the sympathetic nerve activity with hypertension and tachycardia may depend on stimulation of the EP3 receptors in the central nervous system.
Assuntos
Fibras Adrenérgicas/metabolismo , Pressão Sanguínea/fisiologia , Sistema Nervoso Central/metabolismo , Dinoprostona/metabolismo , Frequência Cardíaca/fisiologia , Neurônios/metabolismo , Receptores de Prostaglandina E/metabolismo , Fibras Adrenérgicas/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Ácido Dibenzo(b,f)(1,4)oxazepina-10(11H)-carboxílico, 8-cloro-, 2-acetilidrazida/farmacologia , Dinoprostona/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Masculino , Neurônios/efeitos dos fármacos , Antagonistas de Prostaglandina/farmacologia , Prostaglandinas Sintéticas/farmacologia , Ratos , Ratos Wistar , Receptores de Prostaglandina E/agonistas , Receptores de Prostaglandina E/antagonistas & inibidores , Receptores de Prostaglandina E Subtipo EP1 , Receptores de Prostaglandina E Subtipo EP2 , Receptores de Prostaglandina E Subtipo EP3 , Receptores de Prostaglandina E Subtipo EP4RESUMO
In the liver, carboxylesterase (CES) converts irinotecan (CPT-11) to its active metabolite SN-38, which exerts anticancer effects. SN-38 is metabolized to an inactive metabolite SN-38 glucuronide by uridine 5'-diphospho-glucuronosyltransferase 1A1 (UGT1A1). Therefore, single nucleotide polymorphisms (SNPs) of the UGT1A1 gene are responsible for the severe adverse effects associated with the disruption of SN-38 metabolism. However, despite having SNPs of the UGT1A1 gene, many patients metabolize SN-38 sufficiently to avoid severe adverse effects. Among these patients, we found individuals with elevated serum concentrations of hepatocyte growth factor (HGF). The aim of this study was to evaluate whether HGF alters the metabolism of CPT-11, resulting in a reduction in the anticancer effect of CPT11. The cytotoxicity of CPT-11 and SN-38 was evaluated in HepG2 cells pretreated with HGF. Furthermore, we explored the level of expression and mechanisms of activity of CES and UGT1A1. HGF suppressed the cytotoxicity of CPT-11 by decreasing intracellular SN-38 levels that resulted from a decrease in CES2 and an increase in UGT1A1. Furthermore, this HGF-induced suppression was improved by pretreatment with an inhibitor of HGF receptor c-Met, and the improvement was synergistically potentiated by epidermal growth factor receptor (EGFR) inhibitors. Moreover, HGF induced phosphorylation of signal transducer and activator of transcription 3 and transactivated EGFR. These results suggest that HGF is a possible causative agent of acquired clinical resistance in chemotherapy with CPT-11 and could be useful as a predictor of clinical resistance. Additional treatment using c-Met and/or EGFR inhibitors could be a novel strategy to overcome resistance.
Assuntos
Antineoplásicos/farmacologia , Camptotecina/análogos & derivados , Fator de Crescimento de Hepatócito/fisiologia , Antineoplásicos/metabolismo , Camptotecina/metabolismo , Camptotecina/farmacologia , Carboxilesterase/metabolismo , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/genética , Glucuronosiltransferase/metabolismo , Células Hep G2 , Fator de Crescimento de Hepatócito/farmacologia , Humanos , Irinotecano , Fosforilação , Proteínas Proto-Oncogênicas c-met/genética , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Ativação TranscricionalRESUMO
Statins have pleiotropic vascular protective effects that are independent of their cholesterol-lowering effects. The aim of the present study was to determine if statins have anti-flushing actions in an animal model of forced exercise-induced temperature dysregulation in menopausal hot flushes, and to clarify the critical role of statins in regulating vascular reactivity in the tail arteries of ovariectomized rats. Administration of fluvastatin or pravastatin (3mg/kg/day for 7days, p.o.) significantly ameliorated the flushing of tail skin in ovariectomized mice, and the effect of each statin was comparable with that of estrogen replacement (1mg/kg/week for 3weeks, i.m.). In phenylephrine-pre-contracted rat-tail arteries, ovariectomy inhibited acetylcholine-induced relaxation, but augmented sodium nitroprusside-induced relaxation. These ovariectomy-altered vasodilator responses were restored by fluvastatin treatment as well as by estrogen replacement. Nitrite/nitrate levels in the plasma of ovariectomized animals showed significantly lower values than those in sham-operated animals; this ovariectomy-reduced production of nitric oxide was improved by fluvastatin treatment. These data provide the first experimental evidence that statins such as fluvastatin and pravastatin exert anti-flushing effects by improving vasomotor dysfunction through nitric oxide-mediated mechanisms in ovariectomized animals. Thus, therapeutic methods that target improvement of vasomotor dysfunction could be novel strategies for reducing menopausal hot flushes.
Assuntos
Ácidos Graxos Monoinsaturados/farmacologia , Fogachos/tratamento farmacológico , Indóis/farmacologia , Óxido Nítrico/metabolismo , Ovariectomia , Pravastatina/farmacologia , Sistema Vasomotor/efeitos dos fármacos , Sistema Vasomotor/fisiopatologia , Animais , Artérias/efeitos dos fármacos , Artérias/metabolismo , Artérias/fisiopatologia , Peso Corporal/efeitos dos fármacos , Terapia de Reposição de Estrogênios , Ácidos Graxos Monoinsaturados/uso terapêutico , Feminino , Fluvastatina , Fogachos/sangue , Fogachos/metabolismo , Fogachos/fisiopatologia , Indóis/uso terapêutico , Menopausa/sangue , Menopausa/metabolismo , Camundongos , Óxido Nítrico/sangue , Tamanho do Órgão/efeitos dos fármacos , Condicionamento Físico Animal/efeitos adversos , Pravastatina/uso terapêutico , Ratos , Pele/irrigação sanguínea , Útero/efeitos dos fármacos , Útero/patologia , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Sistema Vasomotor/metabolismoRESUMO
We examined endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxation of mesenteric arteries in high-sodium loaded streptozotocin (STZ)-induced diabetic rats. The study shows that acetylcholine (ACh)-induced, EDHF-mediated relaxation is relatively maintained in STZ-induced diabetic rats, but after a high-sodium diet was given, the function was significantly impaired in STZ-induced diabetic rats.
Assuntos
Fatores Biológicos/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Sódio na Dieta/efeitos adversos , Vasodilatação/efeitos dos fármacos , Acetilcolina , Animais , Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Masculino , Artérias Mesentéricas/fisiopatologia , Fenilefrina , Ratos , Ratos Wistar , Sódio na Dieta/administração & dosagem , EstreptozocinaRESUMO
In this paper, we directly demonstrate, for the first time, the activation of Ca(2+)-dependent protein kinase C (PKC) in the spinal cord of diabetic mice. In streptozotocin (STZ)-treated (200 mg/kg, i.v.) diabetic mice, hypersensitivity (allodynia) to mechanical stimulation appeared 7 d after STZ injection. This mechanical allodynia was inhibited by intrathecal injection of the PKC inhibitors 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7) and calphostin C, but not the protein kinase A inhibitor N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide (H-89). The activity of membrane-associated Ca(2+)-dependent PKC in the spinal cords of STZ-induced diabetic mice was significantly higher than that observed in non-diabetic mice. These results suggest that activation of Ca(2+)-dependent PKC in the spinal cord, contributes to the mechanical allodynia in the pain associated with diabetic neuropathy.