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1.
PLoS One ; 17(6): e0265712, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35749431

RESUMO

The FDA's Accelerated Approval program (AA) is a regulatory program to expedite availability of products to treat serious or life-threatening illnesses that lack effective treatment alternatives. Ideally, all of the many stakeholders such as patients, physicians, regulators, and health technology assessment [HTA] agencies that are affected by AA should benefit from it. In practice, however, there is intense debate over whether evidence supporting AA is sufficient to meet the needs of the stakeholders who collectively bring an approved product into routine clinical care. As AAs have become more common, it becomes essential to be able to determine their impact objectively and reproducibly in a way that provides for consistent evaluation of therapeutic decision alternatives. We describe the basic features of an approach for evaluating AA impact that accommodates stakeholder-specific views about potential benefits, risks, and costs. The approach is based on a formal decision-analytic framework combining predictive distributions for therapeutic outcomes (efficacy and safety) based on statistical models that incorporate findings from AA trials with stakeholder assessments of various actions that might be taken. The framework described here provides a starting point for communicating the value of a treatment granted AA in the context of what is important to various stakeholders.


Assuntos
Aprovação de Drogas , Avaliação da Tecnologia Biomédica , Humanos , Resultado do Tratamento , Estados Unidos , United States Food and Drug Administration
2.
Neuro Oncol ; 24(6): 951-963, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34850166

RESUMO

BACKGROUND: Veledimex (VDX)-regulatable interleukin-12 (IL-12) gene therapy in recurrent glioblastoma (rGBM) was reported to show tumor infiltration of CD8+ T cells, encouraging survival, but also up-regulation of immune checkpoint signaling, providing the rationale for a combination trial with immune checkpoint inhibition. METHODS: An open-label, multi-institutional, dose-escalation phase I trial in rGBM subjects (NCT03636477) accrued 21 subjects in 3 dose-escalating cohorts: (1) neoadjuvant then ongoing nivolumab (1mg/kg) and VDX (10 mg) (n = 3); (2) neoadjuvant then ongoing nivolumab (3 mg/kg) and VDX (10 mg) (n = 3); and (3) neoadjuvant then ongoing nivolumab (3 mg/kg) and VDX (20 mg) (n = 15). Nivolumab was administered 7 (±3) days before resection of the rGBM followed by peritumoral injection of IL-12 gene therapy. VDX was administered 3 hours before and then for 14 days after surgery. Nivolumab was administered every two weeks after surgery. RESULTS: Toxicities of the combination were comparable to IL-12 gene monotherapy and were predictable, dose-related, and reversible upon withholding doses of VDX and/or nivolumab. VDX plasma pharmacokinetics demonstrate a dose-response relationship with effective brain tumor tissue VDX penetration and production of IL-12. IL-12 levels in serum peaked in all subjects at about Day 3 after surgery. Tumor IFNγ increased in post-treatment biopsies. Median overall survival (mOS) for VDX 10 mg with nivolumab was 16.9 months and for all subjects was 9.8 months. CONCLUSION: The safety of this combination immunotherapy was established and has led to an ongoing phase II clinical trial of immune checkpoint blockade with controlled IL-12 gene therapy (NCT04006119).


Assuntos
Antineoplásicos Imunológicos , Glioblastoma , Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Terapia Genética , Glioblastoma/tratamento farmacológico , Glioblastoma/terapia , Humanos , Inibidores de Checkpoint Imunológico , Imunoterapia , Interleucina-12/genética , Nivolumabe/uso terapêutico
3.
Clin Cancer Res ; 15(4): 1428-34, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19228743

RESUMO

PURPOSE: This was a phase I trial to determine the maximum tolerated dose and toxicity of deforolimus (AP23573, MK-8669), an inhibitor of mammalian target of rapamycin (mTOR). The pharmacokinetics, pharmacodynamics, and antineoplastic effects were also studied. EXPERIMENTAL DESIGN: Deforolimus was administered intravenously over 30 min every 7 days according to a flat dosing schedule. Dose was escalated according to an accelerated titration design. Patients remained on study until disease progression as long as they tolerated the drug without significant toxicities. RESULTS: Forty-six patients were enrolled on the study. Common side effects included fatigue, anorexia, and mucositis. The maximum tolerated dose was 75 mg and mucositis was the dose-limiting toxicity. Similar to other mTOR inhibitors, deforolimus exhibited nonlinear pharmacokinetics and a prolonged half-life. Among 34 patients evaluable for response, 1 patient had a partial response, 21 patients had stable disease, and 12 had progressed. Percent change in tumor size was significantly associated with AUC (P=0.015). A significant association was also detected for maximum change in cholesterol within the first two cycles of therapy and change in tumor size (r=-0.38; P=0.029). CONCLUSIONS: Deforolimus was well tolerated on the schedule tested in this trial with toxicity and pharmacokinetic profiles that were similar to that of other mTOR inhibitors. Additional phase II studies are needed to determine if deforolimus is superior to other mTOR inhibitors in terms of efficacy. The change in serum cholesterol as a potential biomarker of activity should be studied further.


Assuntos
Neoplasias/tratamento farmacológico , Proteínas Quinases/efeitos dos fármacos , Sirolimo/análogos & derivados , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Proteínas de Ciclo Celular , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Mucosite/induzido quimicamente , Fosfoproteínas/metabolismo , Fosforilação , Sirolimo/efeitos adversos , Sirolimo/farmacocinética , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR
4.
Ther Innov Regul Sci ; 51(2): 190-199, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30231727

RESUMO

Adaptive design clinical trial methodologies offer both opportunities and challenges for observing basic ethical principles in human subject research. Using both published and unpublished adaptive design clinical trials, we have selected and reviewed examples of clinical trials with different design adaptations to discuss the ethical obstacles presented and often successfully resolved by these approaches, including (1) confirmatory trials for treatments widely accepted on the basis of uncontrolled case series or open-label trials (clinical equipoise and "justice" in the sense of which trial groups will "receive the benefits of research and bear its burdens") (infantile hemangioma/propranolol); (2) interim results analysis by unblinded data monitoring committees ("withholding information necessary to make a considered judgment" ["respect for persons"] versus compromising the trial's scientific basis) (BIG 1-98); (3) adaptations involving sample size reassessment or dose adjustment via dropping or adding treatment arms, allowing fewer subjects to produce statistically significant results, fewer subjects treated with ineffective/toxic doses, and more subjects given doses showing tolerance and treatment activity ("beneficence" or "protecting from harm and making efforts to secure wellbeing") (ECMO, Neuromyelitis Optica); (4) adaptive randomization inferential problems balanced against ethical benefits (trastuzumab vs taxane in advanced gastric cancer; ADVENT); (5) more efficient allocation of societal resources for research, in both public and commercial realms, versus uncertain regulatory acceptance (indicaterol; VALOR); and (6) platform, umbrella, and basket trials offering additional efficiencies (I-SPY II, BATTLE, Lung-MAP). The importance of careful design, meticulous planning, and rigorous ethical review of adaptive design trials on a case-by-case basis cannot be overemphasized.

5.
IEEE Trans Biomed Eng ; 53(5): 800-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16686402

RESUMO

Analysis of synovial fluid by infrared (IR) clinical chemistry requires expert interpretation and is susceptible to subjective error. The application of automated pattern recognition (APR) may enhance the utility of IR analysis. Here, we describe an APR method based on the fuzzy C-means cluster adaptive wavelet (FCMC-AW) algorithm, which consists of two parts: one is a FCMC using the features from an M-band feature extractor adopting the adaptive wavelet algorithm and the second is a Bayesian classifier using the membership matrix generated by the FCMC. A FCMC-cross-validated quadratic probability measure (FCMC-CVQPM) criterion is used under the assumption that the class probability density is equal to the value of the membership matrix. Therefore, both values of posterior probabilities and selection criterion MFQ can be obtained through the membership matrix. The distinctive advantage of this method is that it provides not only the 'hard' classification of a new pattern, but also the confidence of this classification, which is reflected by the membership matrix.


Assuntos
Artrite/diagnóstico , Artrite/metabolismo , Inteligência Artificial , Diagnóstico por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Espectrofotometria Infravermelho/métodos , Líquido Sinovial/química , Algoritmos , Lógica Fuzzy , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
JAMA ; 293(13): 1617-25, 2005 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-15811981

RESUMO

CONTEXT: Alcohol dependence is a common disorder associated with significant morbidity and mortality. Naltrexone, an opioid antagonist, has been shown to be effective for treatment of alcohol dependence. However, adherence to daily oral pharmacotherapy can be problematic, and clinical acceptance and utility of oral naltrexone have been limited. OBJECTIVE: To determine efficacy and tolerability of a long-acting intramuscular formulation of naltrexone for treatment of alcohol-dependent patients. DESIGN, SETTING, AND PARTICIPANTS: A 6-month, randomized, double-blind, placebo-controlled trial conducted between February 2002 and September 2003 at 24 US public hospitals, private and Veterans Administration clinics, and tertiary care medical centers. Of the 899 individuals screened, 627 who were diagnosed as being actively drinking alcohol-dependent adults were randomized to receive treatment and 624 received at least 1 injection. INTERVENTION: An intramuscular injection of 380 mg of long-acting naltrexone (n = 205) or 190 mg of long-acting naltrexone (n = 210) or a matching volume of placebo (n = 209) each administered monthly and combined with 12 sessions of low-intensity psychosocial intervention. MAIN OUTCOME MEASURE: The event rate of heavy drinking days in the intent-to-treat population. RESULTS: Compared with placebo, 380 mg of long-acting naltrexone resulted in a 25% decrease in the event rate of heavy drinking days (P = .02) [corrected] and 190 mg of naltrexone resulted in a 17% decrease (P = .07). Sex and pretreatment abstinence each showed significant interaction with the medication group on treatment outcome, with men and those with lead-in abstinence both exhibiting greater treatment effects. Discontinuation due to adverse events occurred in 14.1% in the 380-mg and 6.7% in the 190-mg group and 6.7% in the placebo group. Overall, rate and time to treatment discontinuation were similar among treatment groups. CONCLUSIONS: Long-acting naltrexone was well tolerated and resulted in reductions in heavy drinking among treatment-seeking alcohol-dependent patients during 6 months of therapy. These data indicate that long-acting naltrexone can be of benefit in the treatment of alcohol dependence.


Assuntos
Alcoolismo/tratamento farmacológico , Naltrexona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Adulto , Alcoolismo/reabilitação , Método Duplo-Cego , Portadores de Fármacos , Feminino , Humanos , Injeções Intramusculares , Ácido Láctico , Masculino , Microesferas , Pessoa de Meia-Idade , Naltrexona/administração & dosagem , Antagonistas de Entorpecentes/administração & dosagem , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros , Psicoterapia Breve
7.
Radiographics ; 24(5): 1257-67; discussion 1267-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15371606

RESUMO

The presence of an implanted pacemaker is widely regarded as an absolute contraindication to magnetic resonance (MR) imaging; however, this viewpoint is based largely on safety concerns in the 1982-1996 period. Since 1996, changes in pacemaker electronics including decreased ferromagnetic content, increased sophistication of the circuitry, and onboard computer capabilities suggest that the absolute contraindication of MR imaging for pacemaker patients should be reconsidered. In addition, there are now data from prospective trials of 232 patients with demand pacemakers who underwent MR imaging at 0.5-1.5 T. Although a variety of pacemaker parameters were evaluated before, during, immediately after, and 3 months after MR imaging, no significant pacemaker changes were identified. No patients reported abnormal sensations such as pacemaker movement or irregular heartbeats even at direct questioning. These results suggest that peripheral locations such as the brain and knee may be considered for MR imaging. Thus, pacemaker patients should be assessed individually for their suitability for MR imaging, which may be performed safely under defined conditions.


Assuntos
Imageamento por Ressonância Magnética , Marca-Passo Artificial , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/prevenção & controle , Artefatos , Ensaios Clínicos como Assunto , Contraindicações , Condutividade Elétrica , Eletrodos Implantados , Eletrônica , Desenho de Equipamento , Falha de Equipamento , Alemanha , Temperatura Alta , Humanos , Imageamento por Ressonância Magnética/métodos , Magnetismo , Movimento (Física) , Oklahoma , Especificidade de Órgãos , Estudos Prospectivos , Estudos Retrospectivos , Risco
8.
Ther Innov Regul Sci ; 48(3): 316-326, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-30235541

RESUMO

Adaptive clinical trials require access to interim data to carry out trial modification as allowed by a prespecified adaptation plan. A data monitoring committee (DMC) is a group of experts that is charged with monitoring accruing trial data to ensure the safety of trial participants and that in adaptive trials may also play a role in implementing a preplanned adaptation. In this paper, we summarize current practices and viewpoints and provide guidance on evolving issues related to the use of DMCs in adaptive trials. We describe the common types of adaptive designs and point out some DMC-related issues that are unique to this class of designs. We include 3 examples of DMCs in late-stage adaptive trials that have been implemented in practice. We advocate training opportunities for researchers who may be interested in serving on a DMC for an adaptive trial since qualified DMC members are fundamental to the successful execution of DMC responsibilities.

9.
Ther Innov Regul Sci ; 47(4): 495-502, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30235521

RESUMO

In this paper, the authors express their views on a range of topics related to data monitoring committees (DMCs) for adaptive trials that have emerged recently. The topics pertain to DMC roles and responsibilities, membership, training, and communication. DMCs have been monitoring trials using the group sequential design (GSD) for over 30 years. While decisions may be more complicated with novel adaptive designs, the fundamental roles and responsibilities of a DMC will remain the same, namely, to protect patient safety and ensure the scientific integrity of the trial. It will be the DMC's responsibility to recommend changes to the trial within the scope of a prespecified adaptation plan or decision criteria and not to otherwise recommend changes to the study design except for serious safety-related concerns. Nevertheless, compared with traditional data monitoring, some additional considerations are necessary when convening DMCs for novel adaptive designs. They include the need to identify DMC members who are familiar with adaptive design and to consider possible sponsor involvement in unique situations. The need for additional expertise in DMC members has prompted some researchers to propose alternative DMC models or alternative governance model. These various options and authors' views on them are expressed in this article.

10.
J Clin Oncol ; 31(19): 2485-92, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23715582

RESUMO

PURPOSE: Aberrant mammalian target of rapamycin (mTOR) signaling is common in sarcomas and other malignancies. Drug resistance and toxicities often limit benefits of systemic chemotherapy used to treat metastatic sarcomas. This large randomized placebo-controlled phase III trial evaluated the mTOR inhibitor ridaforolimus to assess maintenance of disease control in advanced sarcomas. PATIENTS AND METHODS: Patients with metastatic soft tissue or bone sarcomas who achieved objective response or stable disease with prior chemotherapy were randomly assigned to receive ridaforolimus 40 mg or placebo once per day for 5 days every week. Primary end point was progression-free survival (PFS); secondary end points included overall survival (OS), best target lesion response, safety, and tolerability. RESULTS: A total of 711 patients were enrolled, and 702 received blinded study drug. Ridaforolimus treatment led to a modest, although significant, improvement in PFS per independent review compared with placebo (hazard ratio [HR], 0.72; 95% CI, 0.61 to 0.85; P = .001; median PFS, 17.7 v 14.6 weeks). Ridaforolimus induced a mean 1.3% decrease in target lesion size versus a 10.3% increase with placebo (P < .001). Median OS with ridaforolimus was 90.6 weeks versus 85.3 weeks with placebo (HR, 0.93; 95% CI, 0.78 to 1.12; P = .46). Adverse events (AEs) more common with ridaforolimus included stomatitis, infections, fatigue, thrombocytopenia, noninfectious pneumonitis, hyperglycemia, and rash. Grade ≥ 3 AEs were more common with ridaforolimus than placebo (64.1% v 25.6%). CONCLUSION: Ridaforolimus delayed tumor progression to a small statistically significant degree in patients with metastatic sarcoma who experienced benefit with prior chemotherapy. Toxicities were observed with ridaforolimus, as expected with mTOR inhibition. These data provide a foundation on which to further improve control of sarcomas.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Quimioterapia de Manutenção , Sarcoma/tratamento farmacológico , Sarcoma/secundário , Sirolimo/análogos & derivados , Serina-Treonina Quinases TOR/antagonistas & inibidores , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibióticos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Esquema de Medicação , Feminino , Humanos , Cooperação Internacional , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Sirolimo/administração & dosagem , Sirolimo/uso terapêutico , Resultado do Tratamento
11.
Clin Genitourin Cancer ; 10(4): 232-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22695254

RESUMO

BACKGROUND: Few options are available after taxane-based therapy in men with CRPC. Genetic alterations involving the mTOR pathway have been associated with CRPC development, raising the hypothesis that blocking mTOR signaling may be an effective targeted approach to treatment. PATIENTS AND METHODS: In this open-label phase II study, the mTOR inhibitor Ridaforolimus was administered at a dose of 50 mg intravenous once weekly to 38 patients with taxane-treated CRPC. The primary end point was best overall response according to modified Response Evaluation Criteria in Solid Tumors guidelines. Serum prostate-specific antigen levels were prospectively monitored as a biomarker for cancer activity. RESULTS: No objective responses were observed, but 18 patients (47.4%) had stable disease as their best response. Based on progression-free survival analysis, median time to progression with Ridaforolimus was 28 days (95% confidence interval, 27-29). Eight patients (21.1%) had stable disease as their best overall prostate-specific antigen response. The median number of days from first to last dose was 109.5 days (range, 1-442 days). Ridaforolimus was generally well tolerated, with a safety profile similar to that observed in patients with advanced malignancies. The most common side effects were typically mild or moderate in severity. CONCLUSIONS: Ridaforolimus was generally well tolerated. Treatment did not produce objective responses, but stable disease was observed in some patients with taxane-treated CRPC. Alternative treatment regimens, such as combination therapy with a taxane or in a maintenance treatment paradigm, should be considered for further evaluation in this patient population.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/administração & dosagem , Neoplasias da Próstata/tratamento farmacológico , Sirolimo/análogos & derivados , Serina-Treonina Quinases TOR/antagonistas & inibidores , Taxoides/administração & dosagem , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Intervalo Livre de Doença , Esquema de Medicação , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Masculino , Pessoa de Meia-Idade , Orquiectomia , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Sirolimo/administração & dosagem , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo , Taxoides/uso terapêutico , Resultado do Tratamento
12.
J Clin Oncol ; 30(1): 78-84, 2012 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-22067397

RESUMO

PURPOSE: Ridaforolimus is an inhibitor of mammalian target of rapamycin, an integral component of the phosphatidyl 3-kinase/AKT signaling pathway, with early evidence of activity in sarcomas. This multicenter, open-label, single-arm, phase II trial was conducted to assess the antitumor activity of ridaforolimus in patients with distinct subtypes of advanced sarcomas. PATIENTS AND METHODS: Patients with metastatic or unresectable soft tissue or bone sarcomas received ridaforolimus 12.5 mg administered as a 30-minute intravenous infusion once daily for 5 days every 2 weeks. The primary end point was clinical benefit response (CBR) rate (complete response or partial response [PR] or stable disease ≥ 16 weeks). Safety, progression-free survival (PFS), overall survival (OS), time to progression, and duration of response were also evaluated. RESULTS: A total of 212 patients were treated in four separate histologic cohorts. In this heavily pretreated population, 61 patients (28.8%) achieved CBR. Median PFS was 15.3 weeks; median OS was 40 weeks. Response Evaluation Criteria in Solid Tumors (RECIST) confirmed response rate was 1.9%, with four patients achieving confirmed PR (two with osteosarcoma, one with spindle cell sarcoma, and one with malignant fibrous histiocytoma). Archival tumor protein markers analyzed were not correlated with CBR. Related adverse events were generally mild or moderate and consisted primarily of stomatitis, mucosal inflammation, mouth ulceration, rash, and fatigue. CONCLUSION: Single-agent ridaforolimus in patients with advanced and pretreated sarcomas led to PFS results that compare favorably with historical metrics. A phase III trial based on these data will further define ridaforolimus activity in sarcomas.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Sarcoma/tratamento farmacológico , Sirolimo/análogos & derivados , Serina-Treonina Quinases TOR/antagonistas & inibidores , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Biomarcadores Tumorais/sangue , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Sarcoma/metabolismo , Sarcoma/patologia , Fatores Sexuais , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Sirolimo/uso terapêutico , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/sangue
13.
Can Assoc Radiol J ; 56(1): 40-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15835590

RESUMO

OBJECTIVE: To evaluate different imaging protocols, especially with respect to radio frequency (RF) receiver coil location, for their suitability in providing least squares derived quantitative T2 values of ovarian follicular fluid for investigations of basic ovarian physiology. METHODS: The ovaries of 10 women were imaged via magnetic resonance imaging (MRI) using externally positioned and intravaginally placed RF receiver coils. Half-Fourier acquisition with single-shot turbo spin-echo (HASTE), multiple-echo T2, Dixon, turbo spin-echo, and 3-dimensional (3D) fast imaging with steady-state precession (FISP) and time-reversed FISP (PSIF) sequences were used. Quantitative T2 nuclear spin relaxation rate information from the ovarian follicles between data acquired with the external and intravaginal coils were compared. Additionally, the amount of ovarian follicle and corpora lutea structural detail visible was qualitatively assessed. RESULTS: The T2 computations indicated that there was no difference in the follicular fluid T2 values or in the heterogeneity (spatial variance) of the T2 values between data acquired with the external RF coil and data acquired with the intravaginal RF coil. The best sequences for the visualization of ovarian internal structure were the 3D PSIF sequences and the multiple-echo T2-weighted images, confirming our earlier imaging work on excised cow ovaries. CONCLUSION: It is best to use an externally placed RF coil for quantitative MRI study of ovarian physiology given the lack of difference in quantitative T2 information and the difficulty associated with imaging the ovaries using an intravaginal RF probe.


Assuntos
Líquido Folicular , Imageamento por Ressonância Magnética/métodos , Ovário/fisiologia , Adulto , Feminino , Humanos , Imageamento Tridimensional , Análise dos Mínimos Quadrados , Imageamento por Ressonância Magnética/instrumentação , Ondas de Rádio , Vagina
14.
MAGMA ; 16(4): 182-93, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15007746

RESUMO

OBJECTIVE: The objective of the study was to determine the feasibility of using apparent diffusion coefficient (ADC) measurement for the differential diagnosis of malignancy in ovarian masses. MATERIALS AND METHODS: Twelve cases involving ovarian masses were imaged using spin echo diffusion magnetic resonance imaging (MRI). Five cases involved malignant ovarian masses, on the basis of postoperative histologic examination, and the rest involved benign masses. The ovarian masses were imaged in vivo (10 cases) before surgery and ex vivo (8 cases) after surgical resection. Diffusion-weighted data were corrected for motion using the phase data from unweighted data in nine cases. Multifactorial analysis of variance was used to evaluate the effects of malignancy, location (in vivo versus ex vivo), and motion correction on the measurement of ADC intensity and texture. RESULTS: Motion correction caused an undesirable spatial smoothing of the ADC maps and a significant interaction (p=0.047) was found between location and motion correction. ADC value (p=0.028) and texture (p=0.001) differences were found between malignant and nonmalignant ovarian masses. CONCLUSION: Measurement of ADC intensity and texture has the potential to differentially diagnose malignancy in individual ovarian masses if the problem of image motion artifact can be eliminated through the use of faster imaging sequences.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Ovarianas/classificação , Neoplasias Ovarianas/diagnóstico , Adulto , Idoso , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Alcohol Clin Exp Res ; 28(9): 1356-61, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15365306

RESUMO

BACKGROUND: : Oral naltrexone is currently used as part of a treatment regimen for alcohol-dependent patients, but its clinical utility is hampered by poor patient adherence. A long-acting injectable naltrexone formulation (Vivitrex) was designed to facilitate patient adherence by providing an extended duration of therapeutic naltrexone over 1 month, thereby eliminating the need for daily dosing. METHODS: : A multicenter, randomized, double-blind, placebo-controlled pilot study was conducted to evaluate the safety and tolerability of intramuscular repeat dose administration of this extended-release naltrexone formulation in DSM-IV alcohol-dependent patients. Thirty patients were randomized to treatment with injectable naltrexone (400 mg; n = 25) or a matching placebo injection (n = 5) and were dosed once every 28 days over 4 months. Psychosocial treatment was offered to patients in both treatment groups. Outcome measures related to drinking activity and trough plasma concentrations of naltrexone and its primary metabolite, 6-beta-naltrexol, were evaluated. RESULTS: : Injectable naltrexone was generally safe and well tolerated. Reported adverse events were mild to moderate and resolved without intervention; only two patients discontinued due to adverse events. The most common adverse events (nausea and headache) occurred at a similar rate for patients in both treatment groups. Pharmacokinetic analysis confirmed that therapeutic levels of naltrexone were delivered throughout the four 1-month treatment cycles. CONCLUSIONS: : The results of this pilot study provide the basis and methods for a larger, more definitive trial to determine the utility of this long-acting injectable naltrexone formulation in the treatment of alcohol-dependent patients.


Assuntos
Alcoolismo/tratamento farmacológico , Naltrexona/administração & dosagem , Naltrexona/efeitos adversos , Adulto , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/efeitos adversos , Método Duplo-Cego , Avaliação de Medicamentos/métodos , Feminino , Gastroenteropatias/induzido quimicamente , Humanos , Masculino , Projetos Piloto
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