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1.
J Inherit Metab Dis ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795020

RESUMO

BACKGROUND: The most common manifestation of X-linked adrenoleukodystrophy (ALD) is a slowly progressive myeloneuropathy, which leads to imbalance and gait disturbances. The variable progression of the disease complicates evaluation of its progression rate. Wearable sensors allow for easy and frequent balance and gait collection. This study reports baseline data from a longitudinal study on the quantitative assessment of balance and gait with wearable sensors and their clinical relevance. METHODS: Data were collected from adult patients in two institutions. Postural body sway and gait parameters were measured using accelerometers. Disease severity was measured by the Expanded Disability Severity Scale (EDSS). Falling frequency and quality of life (QOL) were collected in men. The relationship between sway and gait variables and EDSS score, participants' use of a walking aid, and falling frequency was evaluated. RESULTS: One hundred twenty individuals with ALD were included. Sway variables significantly differentiate participants' assistive device use. Sway and gait variables were correlated to the EDSS in both sexes. Both gait speed and sway were correlated with falling frequency in men from one institution. Select QOL subscores were correlated with the EDSS in males from one institution. Accelerometry generated comparable results across sites. DISCUSSION: This study confirms the clinical correlation between spinal cord disease and imbalance and gait in ALD. For the first time, this study shows clinically meaningful relationships for sway and gait with use of an assistive device, falling frequency and QOL. Wearable accelerometers are a valid means to measure sway and gait in ALD. These measures are promising outcomes for clinical trial designs to assess myeloneuropathy in ALD and to monitor disease progression in individuals.

2.
Neuropediatrics ; 52(4): 252-260, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34192790

RESUMO

Magnetic resonance imaging (MRI) is the gold standard for the detection of cerebral lesions in X-linked adrenoleukodystrophy (ALD). ALD is one of the most common peroxisomal disorders and is characterized by a defect in degradation of very long chain fatty acids (VLCFA), resulting in accumulation of VLCFA in plasma and tissues. The clinical spectrum of ALD is wide and includes adrenocortical insufficiency, a slowly progressive myelopathy in adulthood, and cerebral demyelination in a subset of male patients. Cerebral demyelination (cerebral ALD) can be treated with hematopoietic cell transplantation (HCT) but only in an early (pre- or early symptomatic) stage and therefore active MRI surveillance is recommended for male patients, both pediatric and adult. Although structural MRI of the brain can detect the presence and extent of cerebral lesions, it does not predict if and when cerebral demyelination will occur. There is a great need for imaging techniques that predict onset of cerebral ALD before lesions appear. Also, imaging markers for severity of myelopathy as surrogate outcome measure in clinical trials would facilitate drug development. New quantitative MRI techniques are promising in that respect. This review focuses on structural and quantitative imaging techniques-including magnetic resonance spectroscopy, diffusion tensor imaging, MR perfusion imaging, magnetization transfer (MT) imaging, neurite orientation dispersion and density imaging (NODDI), and myelin water fraction imaging-used in ALD and their role in clinical practice and research opportunities for the future.


Assuntos
Adrenoleucodistrofia , Adrenoleucodistrofia/diagnóstico por imagem , Adrenoleucodistrofia/terapia , Adulto , Biomarcadores , Criança , Imagem de Tensor de Difusão , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino
3.
J Inherit Metab Dis ; 44(3): 728-739, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33373467

RESUMO

BACKGROUND: Among boys with X-Linked adrenoleukodystrophy, a subset will develop childhood cerebral adrenoleukodystrophy (CCALD). CCALD is typically lethal without hematopoietic stem cell transplant before or soon after symptom onset. We sought to establish evidence-based guidelines detailing the neuroimaging surveillance of boys with neurologically asymptomatic adrenoleukodystrophy. METHODS: To establish the most frequent age and diagnostic neuroimaging modality for CCALD, we completed a meta-analysis of relevant studies published between January 1, 1970 and September 10, 2019. We used the consensus development conference method to incorporate the resulting data into guidelines to inform the timing and techniques for neuroimaging surveillance. Final guideline agreement was defined as >80% consensus. RESULTS: One hundred twenty-three studies met inclusion criteria yielding 1285 patients. The overall mean age of CCALD diagnosis is 7.91 years old. The median age of CCALD diagnosis calculated from individual patient data is 7.0 years old (IQR: 6.0-9.5, n = 349). Ninety percent of patients were diagnosed between 3 and 12. Conventional MRI was most frequently reported, comprised most often of T2-weighted and contrast-enhanced T1-weighted MRI. The expert panel achieved 95.7% consensus on the following surveillance parameters: (a) Obtain an MRI between 12 and 18 months old. (b) Obtain a second MRI 1 year after baseline. (c) Between 3 and 12 years old, obtain a contrast-enhanced MRI every 6 months. (d) After 12 years, obtain an annual MRI. CONCLUSION: Boys with adrenoleukodystrophy identified early in life should be monitored with serial brain MRIs during the period of highest risk for conversion to CCALD.


Assuntos
Adrenoleucodistrofia/diagnóstico , Imageamento por Ressonância Magnética , Criança , Pré-Escolar , Conferências de Consenso como Assunto , Humanos , Lactente , Recém-Nascido , Masculino , Triagem Neonatal/métodos
4.
Int J Dev Neurosci ; 80(1): 52-72, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31909500

RESUMO

Adrenoleukodystrophy (ALD) is a rare X-linked disease caused by a mutation of the peroxisomal ABCD1 gene. This review summarizes our current understanding of the pathogenic cell- and tissue-specific roles of lipid species in the context of experimental therapeutic strategies and provides an overview of critical historical developments, therapeutic trials and the advent of newborn screening in the USA. In ALD, very long-chain fatty acid (VLCFA) chain length-dependent dysregulation of endoplasmic reticulum stress and mitochondrial radical generating systems inducing cell death pathways has been shown, providing the rationale for therapeutic moiety-specific VLCFA reduction and antioxidant strategies. The continuing increase in newborn screening programs and promising results from ongoing and recent therapeutic investigations provide hope for ALD.


Assuntos
Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética , Adrenoleucodistrofia/diagnóstico , Estresse do Retículo Endoplasmático , Humanos , Recém-Nascido , Mutação , Triagem Neonatal
5.
Int J Dev Neurosci ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31778737

RESUMO

Adrenoleukodystrophy (ALD) is a rare X-linked disease caused by a mutation of the peroxisomal ABCD1 gene. This review summarizes our current understanding of the pathogenic cell- and tissue-specific role of lipid species in the context of experimental therapeutic strategies and provides an overview of critical historical developments, therapeutic trials, and the advent of newborn screening in the United States. In ALD, very long chain fatty acid (VLCFA) chain-length-dependent dysregulation of endoplasmic reticulum stress and mitochondrial radical generating systems inducing cell death pathways has been shown, providing the rationale for therapeutic moiety-specific VLCFA reduction and antioxidant strategies. The continuing increase in newborn screening programs and promising results from ongoing and recent therapeutic investigations provide hope for ALD.

6.
Ann Neurol ; 84(3): 452-462, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30069915

RESUMO

OBJECTIVE: X-linked adrenoleukodystrophy (ALD) is a neurodegenerative disorder due to mutations in the peroxisomal very long-chain fatty acyl-CoA transporter, ABCD1, with limited therapeutic options. ALD may manifest in a slowly progressive adrenomyeloneuropathy (AMN) phenotype, or switch to rapid inflammatory demyelinating cerebral disease (cALD), in which microglia have been shown to play a pathophysiological role. The aim of this study was to determine the role of patient phenotype in the immune response of ex vivo monophagocytic cells to stimulation, and to evaluate the efficacy of polyamidoamine dendrimer conjugated to the antioxidant precursor N-acetyl-cysteine (NAC) in modulating this immune response. METHODS: Human monophagocytic cells were derived from fresh whole blood, from healthy (n = 4), heterozygote carrier (n = 4), AMN (n = 7), and cALD (n = 4) patients. Cells were exposed to very long-chain fatty acids (VLCFAs; C24:0 and C26:0) and treated with dendrimer-NAC (D-NAC). RESULTS: Ex vivo exposure to VLCFAs significantly increased tumor necrosis factor α (TNFα) and glutamate secretion from cALD patient macrophages. Additionally, a significant reduction in total intracellular glutathione was observed in cALD patient cells. D-NAC treatment dose-dependently reduced TNFα and glutamate secretion and replenished total intracellular glutathione levels in cALD patient macrophages, more efficiently than NAC. Similarly, D-NAC treatment decreased glutamate secretion in AMN patient cells. INTERPRETATION: ALD phenotypes display unique inflammatory profiles in response to VLCFA stimulation, and therefore ex vivo monophagocytic cells may provide a novel test bed for therapeutic agents. Based on our findings, D-NAC may be a viable therapeutic strategy for the treatment of cALD. Ann Neurol 2018;84:452-462.


Assuntos
Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/metabolismo , Dendrímeros/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Acetilcisteína/metabolismo , Adulto , Idoso , Antioxidantes/metabolismo , Encéfalo/metabolismo , Criança , Feminino , Humanos , Masculino , Microglia/metabolismo , Pessoa de Meia-Idade , Fenótipo , Adulto Jovem
7.
Int Wound J ; 15(6): 914-920, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29956471

RESUMO

Hypertrophic scar formation because of surgical procedures is associated with higher levels of pain, a lower quality of life, and poor cosmetic outcome and requires more resources in follow-up management. An octenidine-based hydrogel has been shown to modulate immunological function in an in vitro wound model, suggesting an improved scar formation. In this prospective, randomised, observer-blinded, and intra-patient-controlled study, 45 patients who underwent abdominoplasty or mastectomy with transverse rectus abdominis muscle (TRAM) flap reconstruction were given both a standard postoperative wound dressing on one wound side and an octenidine-based hydrogel with transparent film dressing, covered with standard postoperative dressing on the other side. Four instances of hypertrophia were reported in the gel side versus 12 in the standard dressing side. Visual Analogue Scale (VAS) pain scores taken during postoperative dressing changes showed reduced scores on the gel side at all time points. Vancouver Scar Scale (VSS) scores showed improvement in the gel side at 3, 6, and 12 months postoperatively. Skin distensibility measured using a cutometer showed significantly improved measures in gel-treated wounds, similar to measures of healthy skin. Trans-epidermal water loss (TEWL), measured using a tewameter, showed improved values on the gel side soon after surgery, with both the control and the gel side normalising after approximately 6 months. The octenidine-based wound dressing demonstrates improved wound healing associated with a lower incidence of hypertrophic scar formation.


Assuntos
Abdominoplastia/métodos , Anti-Infecciosos/uso terapêutico , Cicatriz Hipertrófica/terapia , Hidrogéis/uso terapêutico , Curativos Oclusivos , Piridinas/uso terapêutico , Cicatrização/fisiologia , Adulto , Idoso , Feminino , Humanos , Iminas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
8.
Int Wound J ; 15(1): 84-89, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29057595

RESUMO

Blepharoplasty is the third most common plastic surgical procedure in the USA. Due to the emergence of multiresistant bacteria, optimising the antiseptic procedure is crucial. Choice of antiseptics plays an important role as they may cause skin irritation and colouring of disinfected areas. In this study, the use of the aqueous antiseptic octenisept® (octenidine) was evaluated in the outcome of blepharoplasties: incidence of wound dehiscence; haematoma; and infection in correlation with gender, medication, smoking habits and time of year. This retrospective surveillance study included 352 patients (median age 58·3 years). Skin disinfection was performed thrice prior to blepharoplasty. Sutures were removed on day 6. None of the patients suffered from wound infection. The total rate of wound dehiscence was 6·3%, with a higher ratio among male patients. Smokers and patients on anticoagulant medication showed a significantly higher incidence of wound dehiscence. Throughout the year, rates of wound dehiscence were highest in summer. Aseptic surgical preparation for blepharoplasty via full-face scrub with octenisept® without oral antibiotic prophylaxis is well tolerated, with no report of wound infection, which may improve antibiotic stewardship as well as patient comfort. Elective upper eyelid blepharoplasty may ideally be performed in winter.


Assuntos
Antibacterianos/uso terapêutico , Blefaroplastia/métodos , Pálpebras/cirurgia , Cuidados Pré-Operatórios/métodos , Piridinas/uso terapêutico , Cirurgia Plástica/métodos , Infecção da Ferida Cirúrgica/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Iminas , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Estados Unidos , Cicatrização/fisiologia , Adulto Jovem
9.
Wien Med Wochenschr ; 167(9-10): 219-226, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28493141

RESUMO

Adrenoleukodystrophy (ALD) is an X­linked hereditary disorder due to mutations of the ABCD1 gene, which encodes a peroxisomal transport protein necessary for very long-chain fatty acid degradation (VLCFA). Toxic accumulation thereof is associated with a proinflammatory state and eventual cell death in multiple tissues. ALD may manifest either as a fatal, rapidly progressive demyelinating disease in boys and adult men, or as a slowly progressive adult-onset long-tract myelopathy along with peripheral neuropathy. Our understanding of manifold mechanisms implicated in the disease pathology is currently incomplete, as neither genotype-phenotype correlation nor the trigger for cerebral disease has been described. Therapy objectives are therefore broadly aimed at correcting either the gene mutation or downstream molecular effects, such as oxidative stress. Advancements in disease detection, including the newly implemented newborn screening in the US and imaging modalities, allow for more timely intervention in the form of hematopoietic stem cell transplantation (HSCT), which may only be performed in early cerebral disease states.


Assuntos
Adrenoleucodistrofia/terapia , Adrenoleucodistrofia/diagnóstico , Adrenoleucodistrofia/genética , Adulto , Encefalopatias/diagnóstico , Encefalopatias/genética , Encefalopatias/terapia , Morte Celular/genética , Criança , Cromossomos Humanos X/genética , Análise Mutacional de DNA , Doenças Desmielinizantes/diagnóstico , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/terapia , Progressão da Doença , Transplante de Células-Tronco Hematopoéticas , Humanos , Recém-Nascido , Masculino , Triagem Neonatal
10.
JAMA Neurol ; 74(5): 519-524, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28288261

RESUMO

Importance: X-linked adrenoleukodystrophy (ALD) may switch phenotype to the fatal cerebral form (ie, cerebral ALD [cALD]), the cause of which is unknown. Determining differences in antioxidant capacity and superoxide dismutase (SOD) levels between phenotypes may allow for the generation of a clinical biomarker for predicting the onset of cALD, as well as initiating a more timely lifesaving therapy. Objective: To identify variations in the levels of antioxidant capacity and SOD activity between ALD phenotypes in patients with cALD or adrenomyeloneuropathy (AMN), heterozygote female carriers, and healthy controls and, in addition, correlate antioxidant levels with clinical outcome scores to determine a possible predictive value. Design, Setting, and Participants: Samples of monocytes and blood plasma were prospectively collected from healthy controls, heterozygote female carriers, and patients with AMN or cALD. We are counting each patient as 1 sample in our study. Because adrenoleukodystrophy is an X-linked disease, the affected group populations of cALD and AMN are all male. The heterozygote carriers are all female. The samples were assayed for total antioxidant capacity and SOD activity. The data were collected in an academic hospital setting. Eligibility criteria included patients who received a diagnosis of ALD and heterozygote female carriers, both of which groups were compared with age-matched controls. The prospective samples (n = 30) were collected between January 2015 to January 2016, and existing samples were collected from tissue storage banks at the Kennedy Krieger Institute (n = 30). The analyses were performed during the first 3 months of 2016. Main Outcome and Measures: Commercially available total antioxidant capacity and SOD assays were performed on samples of monocytes and blood plasma and correlated with magnetic resonance imaging severity score. Results: A reduction in antioxidant capacity was shown between the healthy controls (0.225 mmol trolox equivalent) and heterozygote carriers (0.181 mmol trolox equivalent), and significant reductions were seen between healthy controls and patients with AMN (0.102 mmol trolox equivalent; P < .01), as well as healthy controls and patients with cALD (0.042 mmol trolox equivalent; P < .01). Superoxide dismutase activity in human blood plasma mirrored these reductions between prospectively collected samples from healthy controls (2.66 units/mg protein) and samples from heterozygote female carriers (1.91 units/mg protein), patients with AMN (1.39 units/mg protein; P = .01), and patients with cALD (0.8 units/mg protein; P < .01). Further analysis of SOD activity in biobank samples showed significant reductions between patients with AMN (0.89 units/mg protein) and patients with cALD (0.18 units/mg protein) (P = .03). Plasma SOD levels from patients with cALD demonstrated an inverse correlation to brain magnetic resonance imaging severity score (R2 = 0.75, P < .002). Longitudinal plasma SOD samples from the same patients (n = 4) showed decreased activity prior to and at the time of cerebral diagnosis over a period of 13 to 42 months (mean period, 24 months). Conclusions and Relevance: Plasma SOD may serve as a potential biomarker for cerebral disease in ALD following future prospective studies.


Assuntos
Adrenoleucodistrofia/sangue , Antioxidantes/metabolismo , Monócitos/metabolismo , Superóxido Dismutase/metabolismo , Bancos de Tecidos , Adolescente , Adrenoleucodistrofia/diagnóstico por imagem , Adrenoleucodistrofia/genética , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Heterozigoto , Humanos , Lactente , Masculino , Fenótipo , Estudos Prospectivos , Estudos Retrospectivos , Espectrofotometria
11.
Wien Klin Wochenschr ; 129(1-2): 65-69, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27761735

RESUMO

The increasing emigration of graduates of the Medical University of Vienna presents a serious problem. This study examined students' evaluation of clinical rotations, their self-rated performance, and where they felt the most deficits exist. Medical students answered an online questionnaire surveying the following aspects: an evaluation of their internship; supervision; integration in the team and improvement of field-specific knowledge; the qualities of taking a patient's medical history by empathy; patient-centeredness; structure; target orientation; and the ability to integrate field-specific knowledge into anamnesis. The data collected indicate that rotations in Austria, especially in Vienna, were evaluated significantly worse than those abroad. Particularly the lack of supervision and integration in the team were criticized. These data stress a dire need for the reform of curricular structures during clinical rotation in the latter years of medical education.


Assuntos
Centros Médicos Acadêmicos/estatística & dados numéricos , Atitude do Pessoal de Saúde , Competência Clínica/estatística & dados numéricos , Avaliação Educacional/estatística & dados numéricos , Internato e Residência/estatística & dados numéricos , Adulto , Áustria , Emigração e Imigração/estatística & dados numéricos , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde/estatística & dados numéricos , Recursos Humanos
12.
Cancer Chemother Pharmacol ; 78(3): 491-500, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27392790

RESUMO

PURPOSE: Trametinib is a reversible, selective inhibitor of the mitogen-activated extracellular signal-regulated kinase 1 (MEK1) and 2 (MEK2). Cardiotoxicity (congestive heart failure, decreased heart rate, left ventricular dysfunction, and hypertension) related to trametinib is an infrequent, but serious, adverse event (AE). Prolongation of the QT interval increases the risk of life-threatening cardiac arrhythmia. Thus, the risk of trametinib inducing QT prolongation at putative supratherapeutic exposure was evaluated. METHODS: Eligible patients with solid tumours received placebo on day 1, once-daily trametinib 2-mg doses on days 2-14, and a single trametinib 3-mg dose on day 15 to achieve supratherapeutic dosing for QTc measurement. Electrocardiogram was assessed by 12-lead ambulatory 24-h Holter monitoring pre-dose, and on day 1 and day 15. Pharmacokinetic (PK) and pharmacodynamics (PD) parameters were measured. RESULTS: Thirty-two of 35 patients completed the study. There was no effect of trametinib when compared with time-matched placebo on the change from baseline in QTcF, QTcB, or QTcI interval. Mean AUC0-24 and C max following trametinib 2-mg repeat doses were 364 ng.h/mL and 22.9 ng/mL, respectively; the corresponding values for the 3-mg dose were 454 ng.h/mL and 29.2 ng/mL. Median T max was approximately 2 h for both doses. Statistical analysis and PK/PD modelling showed no significant relationship between QTcF interval and trametinib plasma concentrations. AEs were consistent with those reported previously. No electrocardiogram abnormalities were reported as AEs. CONCLUSIONS: The results of this study suggest trametinib has no significant effect on QT prolongation at supratherapeutic exposure.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Piridonas/administração & dosagem , Pirimidinonas/administração & dosagem , Adolescente , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Área Sob a Curva , Cardiotoxicidade/epidemiologia , Eletrocardiografia , Eletrocardiografia Ambulatorial , Feminino , Humanos , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/farmacocinética , Piridonas/efeitos adversos , Piridonas/farmacocinética , Pirimidinonas/efeitos adversos , Pirimidinonas/farmacocinética , Método Simples-Cego , Adulto Jovem
13.
Medicine (Baltimore) ; 94(18): e743, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25950684

RESUMO

The vascular depression (VD) hypothesis postulates that cerebrovascular disease may "predispose, precipitate, or perpetuate" a depressive syndrome in elderly patients. Clinical presentation of VD has been shown to differ to major depression in quantitative disability; however, as little research has been made toward qualitative phenomenological differences in the personality aspects of the symptom profile, clinical diagnosis remains a challenge.We attempted to identify differences in clinical presentation between depression patients (n = 50) with (n = 25) and without (n = 25) vascular disease using questionnaires to assess depression, affect regulation, object relations, aggressiveness, alexithymia, personality functioning, personality traits, and counter transference.We were able to show that patients with vascular dysfunction and depression exhibit significantly higher aggressive and auto-aggressive tendencies due to a lower tolerance threshold. These data indicate that VD is a separate clinical entity and secondly that the role of personality itself may be a component of the disease process. We propose an expanded threshold disease model incorporating personality functioning and mood changes. Such findings might also aid the development of a screening program, by serving as differential criteria, ameliorating the diagnostic procedure.


Assuntos
Transtornos Cerebrovasculares/complicações , Transtorno Depressivo/diagnóstico , Adulto , Idoso , Estudos de Casos e Controles , Transtornos Cerebrovasculares/psicologia , Transtorno Depressivo/etiologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Personalidade , Escalas de Graduação Psiquiátrica , Testes Psicológicos , Autorrelato , Inquéritos e Questionários
14.
J Clin Pharmacol ; 55(6): 661-70, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25612153

RESUMO

A thorough QT study was conducted in healthy volunteers with losmapimod. Four treatment regimens were included: a therapeutic dose (7.5 mg BID for 5 days), a supratherapeutic dose (20 mg QD for 5 days), a positive control (400 mg moxifloxacin single dose on Day 5), and placebo for 5 days. Baseline and on treatment ECGs were measured on Day 1 (3 timepoints predose) and Day 5, respectively. The primary statistical analysis failed to demonstrate a lack of effect of losmapimod on the QT interval leading to a positive finding. However, simulations using the concentration-effect model established for QTcF vs. losmapimod concentration at concentrations 4× the maximum concentration of the therapeutic dose did not exceed the regulatory thresholds of concern of 5 milliseconds for the mean (4.57 milliseconds) and 10 milliseconds for the upper bound of the 90%CI (90%CI 2.88, 6.10). Modeling demonstrated that the discrepant results may have been due to a baseline shift after repeat dosing and baseline differences between the treatments. Considering the results of the concentration-effect modeling, previous losmapimod data, and the high false-positive rate associated with the ICH E14 statistical analysis, the statistical analysis was likely a false-positive.


Assuntos
Ciclopropanos/farmacologia , Eletrocardiografia , Frequência Cardíaca/efeitos dos fármacos , Síndrome do QT Longo/induzido quimicamente , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Adulto , Idoso , Estudos Cross-Over , Ciclopropanos/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Fluoroquinolonas/administração & dosagem , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Moxifloxacina , Inibidores de Proteínas Quinases/administração & dosagem , Piridinas/administração & dosagem , Inibidores da Topoisomerase II/administração & dosagem , Adulto Jovem
15.
J Clin Pharmacol ; 54(9): 995-1005, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24700490

RESUMO

Tafenoquine is being developed for relapse prevention in Plasmodium vivax malaria. This Phase I, single-blind, randomized, placebo- and active-controlled parallel group study investigated whether tafenoquine at supratherapeutic and therapeutic concentrations prolonged cardiac repolarization in healthy volunteers. Subjects aged 18-65 years were randomized to one of five treatment groups (n = 52 per group) to receive placebo, tafenoquine 300, 600, or 1200 mg, or moxifloxacin 400 mg (positive control). Lack of effect was demonstrated if the upper 90% CI of the change from baseline in QTcF following supratherapeutic tafenoquine 1200 mg versus placebo (ΔΔQTcF) was <10 milliseconds for all pre-defined time points. The maximum ΔΔQTcF with tafenoquine 1200 mg (n = 50) was 6.39 milliseconds (90% CI 2.85, 9.94) at 72 hours post-final dose; that is, lack of effect for prolongation of cardiac depolarization was demonstrated. Tafenoquine 300 mg (n = 48) or 600 mg (n = 52) had no effect on ΔΔQTcF. Pharmacokinetic/pharmacodynamic modeling of the tafenoquine-QTcF concentration-effect relationship demonstrated a shallow slope (0.5 ms/µg mL(-1) ) over a wide concentration range. For moxifloxacin (n = 51), maximum ΔΔQTcF was 8.52 milliseconds (90% CI 5.00, 12.04), demonstrating assay sensitivity. In this thorough QT/QTc study, tafenoquine did not have a clinically meaningful effect on cardiac repolarization.


Assuntos
Aminoquinolinas/farmacologia , Antimaláricos/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Adolescente , Adulto , Idoso , Aminoquinolinas/efeitos adversos , Aminoquinolinas/sangue , Aminoquinolinas/farmacocinética , Antimaláricos/efeitos adversos , Antimaláricos/sangue , Antimaláricos/farmacocinética , Eletrocardiografia/efeitos dos fármacos , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Método Simples-Cego , Adulto Jovem
16.
J Clin Pharmacol ; 54(7): 818-27, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24443277

RESUMO

Ofatumumab is a human monoclonal antibody directed at CD20 approved for treatment of chronic lymphocytic leukemia. The population pharmacokinetics of intravenous ofatumumab were characterized in patients with relapsed/refractory chronic lymphocytic leukemia, relapsed/refractory follicular lymphoma, and rheumatoid arthritis, diseases with widely varying CD20⁺ B-cell counts in blood. Serum concentration data from a total of 477 patients who received ofatumumab doses ranging from 100 mg to 2000 mg in different dosing regimens were analyzed to determine the pharmacokinetic characteristics of ofatumumab across different patient groups and to identify factors contributing to the pharmacokinetic variability. Ofatumumab pharmacokinetics were well described by a linear two-compartment model component to represent non-specific monoclonal antibody clearance from the central compartment interacting with a model component representing the target-mediated clearance of ofatumumab by binding to CD20 expressed on B cells. The clearance (7.5 mL/h) and steady-state volume of distribution (5.3 L) for the linear, non-specific component were consistent with results obtained for other monoclonal antibodies. The target-mediated clearance component was related to the disease-specific number of circulating B cells, which will allow simulation of the contribution of target-mediated clearance to ofatumumab pharmacokinetics in untested disease states with data on B-cell counts and turnover.


Assuntos
Anticorpos Monoclonais/farmacocinética , Artrite Reumatoide/imunologia , Linfócitos B/efeitos dos fármacos , Monitoramento de Medicamentos/métodos , Leucemia Linfocítica Crônica de Células B/imunologia , Linfoma Folicular/imunologia , Modelos Biológicos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/sangue , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/sangue , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antígenos CD20/química , Antígenos CD20/metabolismo , Antineoplásicos/administração & dosagem , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Artrite Reumatoide/sangue , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/sangue , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/metabolismo , Linfoma Folicular/sangue , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/metabolismo , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Recidiva , Reprodutibilidade dos Testes
17.
J Clin Pharmacol ; 51(1): 19-28, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20421511

RESUMO

The objective was to characterize the pharmacokinetics (PK) and pharmacodynamics (PD) of argatroban in pediatric patients and derive dosing recommendations. An open-label multicenter trial was conducted in pediatric patients (n = 18 from birth to 16 years). A population modeling approach was used to characterize pharmacokinetics and pharmacodynamics of argatroban in pediatric patients. Simulations were performed to derive a dosing regimen for pediatric patients. The estimated clearance of argatroban in pediatric patients was 2-fold lower than that in healthy adults. Body weight was significant predictor of argatroban clearance. The clearance in a typical 20-kg pediatric patient was 3.1 L/h. In 4 patients with elevated serum bilirubin levels, the estimated clearance was 0.6 L/h. Effect on activated plasma thromboplastin time (aPTT) was found to be concentration dependent. Simulations suggested that a starting dose of 0.75 µg/kg/min in pediatric patients was comparable in performance to 2.0 µg/kg/min approved in adults for attaining target aPTT and risk for bleeding. A dose increment step size of 0.25 µg/kg/min was suitable for titration. The PK/PD of argatroban was reasonably characterized in pediatrics. Plasma concentration-aPTT relationship was used to derive a safe starting dose and titration scheme for the first time in pediatric patients and was incorporated into the US prescribing information for argatroban.


Assuntos
Modelos Biológicos , Ácidos Pipecólicos/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Adolescente , Arginina/análogos & derivados , Bilirrubina/sangue , Peso Corporal , Criança , Pré-Escolar , Simulação por Computador , Relação Dose-Resposta a Droga , Feminino , Hemorragia/etiologia , Humanos , Lactente , Recém-Nascido , Masculino , Tempo de Tromboplastina Parcial , Ácidos Pipecólicos/farmacocinética , Ácidos Pipecólicos/farmacologia , Inibidores da Agregação Plaquetária/farmacocinética , Inibidores da Agregação Plaquetária/farmacologia , Sulfonamidas
18.
Fitoterapia ; 77(5): 406-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16814487

RESUMO

The hydro-alcoholic extract of the aerial parts of Lithraea molleoides, given orally at a dose of 1000 mg/kg, showed significant anti-ulcerogenic activity on ulcer induced by indomethacin and absolute alcohol in rats.


Assuntos
Anacardiaceae/química , Antiulcerosos/análise , Animais , Masculino , Fitoterapia , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Ratos , Ratos Wistar , Úlcera Gástrica/tratamento farmacológico
19.
Am J Cardiol ; 93(11): 1378-83, A6, 2004 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15165918

RESUMO

This novel study evaluated the effects of vardenafil and sildenafil on QT and corrected QT (QTc) duration using a model that minimizes experimental error to obtain the most accurate assessment of observed QTc effects. A placebo-controlled and positive-controlled, period-balanced, double-blinded, 6-way crossover study evaluated therapeutic and supratherapeutic oral doses of vardenafil (10 and 80 mg, respectively) and sildenafil (50 and 400 mg, respectively), therapeutic doses of moxifloxacin (400 mg), and a placebo in 58 healthy men (mean age 53 years), with dosing every 3 days. Six replicate, 12-lead, digital electrocardiograms (ECGs) were recorded at 3 time points before and 5 time points after dosing to cover the time course of maximum exposure to study drugs and their metabolites. An independent laboratory blindly analyzed approximately 17,000 ECGs. For the placebo, mean change in QTcF (Fridericia) duration 1 hour after dose (approximate Tmax of vardenafil and sildenafil) was 0 ms (+/-0.7 SD). QT/QTc variability was small across regimens, indicating statistically powerful results. Moxifloxacin demonstrated an expected 8-ms mean change and was the only drug to prolong absolute QT. Placebo-corrected mean changes in QTcF duration (90% confidence interval) at 1 hour after dose were 8 ms (range 6 to 9) for vardenafil 10 mg and 6 ms (range 5 to 8) for sildenafil 50 mg. QTci (linear and nonlinear per patient) yielded similar trends: 4 ms (range 3 to 6) for vardenafil 10 mg and 4 ms (range 2 to 5) for sildenafil 50 mg. Dose response demonstrated very shallow QTc relations for study drugs. Therapeutic and supratherapeutic doses produced only small increases in the QTcF interval, which were considered to be clinically irrelevant. This well-controlled, statistically powerful study in middle-aged men demonstrated that vardenafil and sildenafil produced no increase of absolute QT and only similar, small increases of the QTc interval, with a shallow dose-response curve. The study design and conduct may serve as a guide for future QT assessment of new drugs.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/antagonistas & inibidores , Eletrocardiografia/efeitos dos fármacos , Coração/efeitos dos fármacos , Imidazóis/farmacologia , Piperazinas/farmacologia , Compostos Aza/administração & dosagem , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Fluoroquinolonas , Humanos , Imidazóis/administração & dosagem , Masculino , Pessoa de Meia-Idade , Moxifloxacina , Piperazinas/administração & dosagem , Purinas , Quinolinas/administração & dosagem , Citrato de Sildenafila , Sulfonas , Fatores de Tempo , Triazinas , Dicloridrato de Vardenafila
20.
Reprod Health Matters ; 10(19): 184-8, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12369325

RESUMO

In strongly patriarchal societies, where the cultural and economic value of sons is at a premium, son preference manifests itself in many ways, ranging from differential allocation of household resources, medical care and neglect of girl children to female infanticide. With the increasing availability of ultrasound in the mid-1980s sex determination followed by sex-selective abortion began to become widespread as well. The following paper introduces this Roundtable and discusses the following questions: Is sex selection a part of women's right to free choice and control over their reproduction? What is the role of the medical profession? Are all manifestations of sex selection equally unethical? Are there solutions? Do the solutions themselves pose new ethical dilemmas? Following this paper, four respondents put different points of view on sex selection as a gender-based preference for a pregnancy; progress in getting the Supreme Court of India to implement a 1994 law regulating the use of antenatal diagnostic technology; why sex selection should be available as a form of reproductive choice; and why sex selection may be empowering for women and justify their actions in the short run, given the demands on them. All agree that only improved status for women and girls will reduce the demand for sex selection.


Assuntos
Pré-Seleção do Sexo , Aborto Induzido , Bioética , Feminino , Humanos , Masculino , Gravidez , Preconceito , Análise para Determinação do Sexo , Razão de Masculinidade , Predomínio Social
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