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1.
BMC Cancer ; 23(1): 788, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37612610

RESUMO

BACKGROUND: Glioblastoma (GBM) is the most common primary, malignant brain tumour with a 5-year survival of 5%. If possible, a glioblastoma is resected and further treated with chemoradiation therapy (CRT), but resection is not feasible in about 30% of cases. Current standard of care in these cases is a biopsy followed by CRT. Magnetic resonance (MR) imaging-guided laser interstitial thermal therapy (LITT) has been suggested as a minimally invasive alternative when surgery is not feasible. However, high-quality evidence directly comparing LITT with standard of care is lacking, precluding any conclusions on (cost-)effectiveness. We therefore propose a multicenter randomized controlled study to assess the (cost-)effectiveness of MR-guided LITT as compared to current standard of care (EMITT trial). METHODS AND ANALYSIS: The EMITT trial will be a multicenter pragmatic randomized controlled trial in the Netherlands. Seven Dutch hospitals will participate in this study. In total 238 patients will be randomized with 1:1 allocation to receive either biopsy combined with same-session MR-guided LITT therapy followed by CRT or the current standard of care being biopsy followed by CRT. The primary outcomes will be health-related quality of life (HR-QoL) (non-inferiority) using EORTC QLQ-C30 + BN20 scores at 5 months after randomization and overall survival (superiority). Secondary outcomes comprise cost-effectiveness (healthcare and societal perspective) and HR-QoL of life over an 18-month time horizon, progression free survival, tumour response, disease specific survival, longitudinal effects, effects on adjuvant treatment, ablation percentage and complication rates. DISCUSSION: The EMITT trial will be the first RCT on the effectiveness of LITT in patients with glioblastoma as compared with current standard of care. Together with the Dutch Brain Tumour Patient association, we hypothesize that LITT may improve overall survival without substantially affecting patients' quality of life. TRIAL REGISTRATION: This trial is registered at ClinicalTrials.gov (NCT05318612).


Assuntos
Glioblastoma , Hipertermia Induzida , Humanos , Qualidade de Vida , Glioblastoma/diagnóstico , Glioblastoma/terapia , Biópsia , Adjuvantes Imunológicos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
2.
J Neurooncol ; 164(2): 405-412, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37505379

RESUMO

PURPOSE: Laser interstitial thermal therapy (LITT) is increasingly being used in the treatment of brain tumors, whereas high-quality evidence of its effectiveness is lacking. This pilot examined the feasibility of conducting a randomized controlled trial (RCT) in patients with irresectable newly diagnosed glioblastoma (nGBM), and generated data on technical feasibility and safety. METHODS: We included patients with irresectable nGBM with KPS ≥ 70 and feasible trajectories to ablate ≥ 70% of the tumor volume. Patients were initially randomized to receive either biopsy combined with LITT or biopsy alone, followed by chemoradiation (CRT). Randomization was stopped after 9 patients as the feasibility endpoint with respect to willingness to be randomized was met. Main endpoints were feasibility of performing an RCT, technical feasibility of LITT and safety. Follow-up was 3 months. RESULTS: A total of 15 patients were included, of which 10 patients received a biopsy followed by LITT and 5 patients a biopsy. Most patients were able to complete the follow-up procedures (93% clinical, 86% questionnaires, 78% MRI). Patients were planned within 3 weeks after consultation (median 12 days, range 8-16) and no delay was observed in referring patients for CRT (median 37 days, range 28-61). Two CD ≥ 3 complications occurred in the LITT arm and none in the biopsy arm. CONCLUSION: An RCT to study the effectiveness of LITT in patients with an irresectable nGBM seems feasible with acceptable initial safety data. The findings from this pilot study helped to further refine the design of a larger full-scale multicenter RCT in the Netherlands. Protocol and study identifier: The current study is registered at clinicaltrials.gov (EMITT pilot study, NTR: NCT04596930).


Assuntos
Neoplasias Encefálicas , Glioblastoma , Terapia a Laser , Humanos , Glioblastoma/cirurgia , Terapia a Laser/métodos , Projetos Piloto , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Neoplasias Encefálicas/cirurgia , Resultado do Tratamento
3.
NMR Biomed ; 34(5): e4169, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-31518036

RESUMO

31 P MR spectroscopic imaging (MRSI) is a versatile technique to study phospholipid precursors and energy metabolism in the healthy and diseased human brain. However, mainly due to its low sensitivity, 31 P MRSI is currently limited to research purposes. To obtain 3D 31 P MRSI spectra with improved signal-to-noise ratio on clinical 3 T MR systems, we used a coil combination consisting of a dual-tuned birdcage transmit coil and a 31 P eight-channel phased-array receive insert. To further increase resolution and sensitivity we applied WALTZ4 1 H decoupling and continuous wave nuclear Overhauser effect (NOE) enhancement and acquired high-quality MRSI spectra with nominal voxel volumes of ~ 17.6 cm3 (effective voxel volume ~ 51 cm3 ) in a clinically relevant measurement time of ~ 13 minutes, without exceeding SAR limits. Steady-state NOE enhancements ranged from 15 ± 9% (γ-ATP) and 33 ± 3% (phosphocreatine) to 48 ± 11% (phosphoethanolamine). Because of these improvements, we resolved and detected all 31 P signals of metabolites that have also been reported for ultrahigh field strengths, including resonances for NAD+ , NADH and extracellular inorganic phosphate. T1 times of extracellular inorganic phosphate were longer than for intracellular inorganic phosphate (3.8 ± 1.4s vs 1.8 ± 0.65 seconds). A comparison of measured T1 relaxation times and NOE enhancements at 3 T with published values between 1.5 and 9.4 T indicates that T1 relaxation of 31 P metabolite spins in the human brain is dominated by dipolar relaxation for this field strength range. Even although intrinsic sensitivity is higher at ultrahigh fields, we demonstrate that at a clinical field strength of 3 T, similar 31 P MRSI information content can be obtained using a sophisticated coil design combined with 1 H decoupling and NOE enhancement.


Assuntos
Encéfalo/diagnóstico por imagem , Espectroscopia de Ressonância Magnética , NAD/metabolismo , Trifosfato de Adenosina/metabolismo , Adulto , Feminino , Humanos , Masculino , Metaboloma , Fosfatos/análise , Fosfocreatina/análogos & derivados , Fosfocreatina/metabolismo , Fósforo , Espectroscopia de Prótons por Ressonância Magnética , Processamento de Sinais Assistido por Computador , Fatores de Tempo
4.
Magn Reson Med ; 82(2): 825-832, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30900352

RESUMO

PURPOSE: To demonstrate a 1 H/31 P whole human brain volume coil configuration for 3 Tesla with separate 31 P transmit and receive components that maintains 1 H MRS performance and delivers optimal 31 P MRSI with 1 H decoupling. METHODS: We developed an 8-channel 31 P receive array coil covering the head to be used as an insert for a commercial double-tuned 1 H/31 P birdcage transmit-receive coil. This retains the possibility of using low-power rectangular pulses for 1 H-decoupled 3D 31 P MRSI (nominal resolution 17.6 cm3 ; acquisition duration 13 min) but increases the SNR with the receive sensitivity of 31 P surface coils. The performance of the combined coil setup was evaluated by measuring 1 H and 31 P SNR with and without the 31 P receive array and by assessing the effect of the receive array on the transmit efficiencies of the birdcage coil. RESULTS: Compared to the birdcage coil alone, the 31 P insert in combination with the birdcage achieved an average 31 P SNR gain of 1.4 ± 0.4 in a center partition of the brain. The insert did not cause losses in 1 H MRS performance and transmit efficiency, whereas for 31 P approximately 20% more power was needed to achieve the same γB1. CONCLUSION: The new coil configuration allows 1 H MRSI and optimal 1 H-decoupled 3D 31 P MRSI, with increased SNR of the human brain without patient repositioning, for clinical and research purposes at 3 Tesla.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Adulto , Algoritmos , Encéfalo/diagnóstico por imagem , Desenho de Equipamento , Feminino , Humanos , Masculino , Imagens de Fantasmas
5.
PLoS One ; 17(8): e0268881, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36001537

RESUMO

PURPOSE: To evaluate the value of convolutional neural network (CNN) in the diagnosis of human brain tumor or Alzheimer's disease by MR spectroscopic imaging (MRSI) and to compare its Matthews correlation coefficient (MCC) score against that of other machine learning methods and previous evaluation of the same data. We address two challenges: 1) limited number of cases in MRSI datasets and 2) interpretability of results in the form of relevant spectral regions. METHODS: A shallow CNN with only one hidden layer and an ad-hoc loss function was constructed involving two branches for processing spectral and image features of a brain voxel respectively. Each branch consists of a single convolutional hidden layer. The output of the two convolutional layers is merged and fed to a classification layer that outputs class predictions for the given brain voxel. RESULTS: Our CNN method separated glioma grades 3 and 4 and identified Alzheimer's disease patients using MRSI and complementary MRI data with high MCC score (Area Under the Curve were 0.87 and 0.91 respectively). The results demonstrated superior effectiveness over other popular methods as Partial Least Squares or Support Vector Machines. Also, our method automatically identified the spectral regions most important in the diagnosis process and we show that these are in good agreement with existing biomarkers from the literature. CONCLUSION: Shallow CNNs models integrating image and spectral features improved quantitative and exploration and diagnosis of brain diseases for research and clinical purposes. Software is available at https://bitbucket.org/TeslaH2O/cnn_mrsi.


Assuntos
Doença de Alzheimer , Neoplasias Encefálicas , Doença de Alzheimer/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Humanos , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação
6.
J Gerontol A Biol Sci Med Sci ; 75(11): 2169-2176, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32449919

RESUMO

BACKGROUND: Impaired recovery of blood pressure (BP) after standing has been shown to be related to cognitive function and mortality in people without dementia, but its role in people with Alzheimer's disease (AD) is unknown. The aim of this study was to investigate the association of the orthostatic BP response with cognitive decline and mortality in AD. METHODS: In this post hoc analysis of a randomized controlled trial (Nilvad), we measured the beat-to-beat response of BP upon active standing in mild-to-moderate AD. This included the initial drop (nadir within 40 seconds) and recovery after 1 minute, both expressed relative to resting values. We examined the relationship between a small or large initial drop (median split) and unimpaired (≥100%) or impaired recovery (<100%) with 1.5-year change in Alzheimer's Disease Assessment-cognitive subscale (ADAS-cog) scores and all-cause mortality. RESULTS: We included 55 participants (age 73.1 ± 6.2 years). Impaired BP recovery was associated with higher increases in ADAS-cog scores (systolic: ß [95% confidence interval] = 5.6 [0.4-10.8], p = .035; diastolic: 7.6 [2.3-13.0], p = .006). During a median follow-up time of 49 months, 20 participants died. Impaired BP recovery was associated with increased mortality (systolic: HR [95% confidence interval] = 2.9 [1.1-7.8], p = .039; diastolic: HR [95% confidence interval] = 5.5 [1.9-16.1], p = .002). The initial BP drop was not associated with any outcome. Results were adjusted for age, sex, and intervention group. CONCLUSIONS: Failure to fully recover BP after 1 minute of standing is associated with cognitive decline and mortality in AD. As such, BP recovery can be regarded as an easily obtained marker of progression rate of AD.


Assuntos
Doença de Alzheimer/mortalidade , Disfunção Cognitiva , Hipotensão Ortostática/fisiopatologia , Idoso , Biomarcadores , Progressão da Doença , Feminino , Humanos , Masculino
7.
Hypertension ; 74(2): 413-420, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31203725

RESUMO

Cerebrovascular changes, including reduced cerebral blood flow (CBF), occur early in the development of Alzheimer disease and may accelerate disease progression. This randomized, double-blind, placebo-controlled study investigated how 6 months of treatment with the calcium antagonist nilvadipine would affect CBF in patients with mild-to-moderate Alzheimer disease. CBF was measured with magnetic resonance arterial spin labeling in whole-brain gray matter and in a priori defined regions of interest including the hippocampus. Fifty-eight patients were randomly assigned (29 in each group), of whom 22 in both groups had no magnetic resonance exclusion criteria and were medication compliant over 6 months. Mean age was 72.8±6.2 years, mean mini-mental state examination was 20.4±3.4. Nilvadipine treatment lowered systolic blood pressure (Δ=-11.5 [95% CI, -19.7 to -3.2] mm Hg; P<0.01), while whole-brain gray-matter CBF remained stable (Δ=5.4 [95% CI, -6.4 to 17.2] mL/100 g per minute; P=0.36). CBF in the hippocampus increased (left: Δ=24.4 [95% CI, 4.3-44.5] mL/100 g per minute; P=0.02; right: Δ=20.1 [95% CI, -0.6 to 40.8] mL/100 g per minute; P=0.06). There was no significant change in CBF in the posterior cingulate cortex (Δ=5.2 [95% CI, -16.5 to 27.0] mL/100 g per minute; P=0.63) or other regions of interest. In conclusion, nilvadipine reduced blood pressure and increased CBF in the hippocampus, whereas other regions showed stable or small nonsignificant increases in CBF. These findings not only indicate preserved cerebral autoregulation in Alzheimer disease but also point toward beneficial cerebrovascular effects of antihypertensive treatment. Clinical Trial Registration- URL: http://www.clinicaltrials.gov . Unique identifier: NCT02017340.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Circulação Cerebrovascular/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Nifedipino/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Método Duplo-Cego , Feminino , Humanos , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Países Baixos , Nifedipino/uso terapêutico , Prognóstico , Valores de Referência , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Ultrassonografia Doppler/métodos
8.
Neuroimage Clin ; 18: 254-261, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29876246

RESUMO

In Alzheimer's disease (AD), defects in essential metabolic processes for energy supply and phospholipid membrane function have been implicated in the pathological process. However, post-mortem investigations are generally limited to late stage disease and prone to tissue decay artifacts. In vivo assessments of high energy phosphates, tissue pH and phospholipid metabolites are possible by phosphorus MR spectroscopy (31P-MRS), but so far only small studies, mostly focusing on single brain regions, have been performed. Therefore, we assessed phospholipid and energy metabolism in multiple brain regions of 31 early stage AD patients and 31 age- and gender-matched controls using 31P-MRS imaging. An increase of phosphocreatine (PCr) was found in AD patients compared with controls in the retrosplenial cortex, and both hippocampi, but not in the anterior cingulate cortex. While PCr/inorganic phosphate and pH were also increased in AD, no changes were found for phospholipid metabolites. This study showed that PCr levels are specifically increased in regions that show early degeneration in AD. Together with an increased pH, this indicates an altered energy metabolism in mild AD.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Metabolismo Energético/fisiologia , Fosfolipídeos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Espectroscopia de Ressonância Magnética , Masculino
9.
Alzheimers Res Ther ; 9(1): 51, 2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28747210

RESUMO

BACKGROUND: Synaptic dysfunction contributes to cognitive impairment in Alzheimer's disease and may be countered by increased intake of nutrients that target brain phospholipid metabolism. In this study, we explored whether the medical food Souvenaid affects brain phospholipid metabolism in patients with Alzheimer's disease. METHODS: Thirty-four drug-naive patients with mild Alzheimer's disease (Mini Mental State Examination score ≥20) were enrolled in this exploratory, double-blind, randomized controlled study. Before and after 4-week intervention with Souvenaid or an isocaloric control product, phosphorus and proton magnetic resonance spectroscopy (MRS) was performed to assess surrogate measures of phospholipid synthesis and breakdown (phosphomonoesters [PME] and phosphodiesters [PDEs]), neural integrity (N-acetyl aspartate), gliosis (myo-inositol), and choline metabolism (choline-containing compounds [tCho]). The main outcome parameters were PME and PDE signal intensities and the PME/PDE ratio. RESULTS: MRS data from 33 patients (60-86 years old; 42% males; Souvenaid arm n = 16; control arm n = 17) were analyzed. PME/PDE and tCho were higher after 4 weeks of Souvenaid compared with control (PME/PDE least squares [LS] mean difference [95% CI] 0.18 [0.06-0.30], p = 0.005; tCho LS mean difference [95% CI] 0.01 [0.00-0.02], p = 0.019). No significant differences were observed in the other MRS outcome parameters. CONCLUSIONS: MRS reveals that Souvenaid affects brain phospholipid metabolism in mild Alzheimer's disease, in line with findings in preclinical studies. TRIAL REGISTRATION: Netherlands Trial Register, NTR3346 . Registered on 13 March 2012.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Encéfalo/efeitos dos fármacos , Alimentos Formulados , Nootrópicos/administração & dosagem , Fosfolipídeos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Bebidas , Encéfalo/metabolismo , Colina/metabolismo , Ácidos Docosa-Hexaenoicos/administração & dosagem , Método Duplo-Cego , Ácido Eicosapentaenoico/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Resultado do Tratamento
10.
Alzheimers Res Ther ; 7(1): 51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26213579

RESUMO

INTRODUCTION: Circulating levels of uridine, selenium, vitamins B12, E and C, folate, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have been shown to be lower in patients with Alzheimer's disease (AD) than in healthy individuals. These low levels may affect disease pathways involved in synapse formation and neural functioning. Here, we investigated whether, and to what extent, circulating levels of micronutrients and fatty acids can be affected by oral supplementation with Souvenaid (containing a specific nutrient combination), using data derived from three randomized clinical trials (RCT) and an open-label extension (OLE) study with follow-up data from 12 to 48 weeks. METHODS: Subjects with mild (RCT1, RCT2) or mild-to-moderate AD (RCT3) received active or control product once daily for 12-24 weeks or active product during the 24-week OLE following RCT2 (n = 212-527). Measurements included plasma levels of B vitamins, choline, vitamin E, selenium, uridine and homocysteine and proportions of DHA, EPA and total n-3 long-chain polyunsaturated fatty acids in plasma and erythrocytes. Between-group comparisons were made using t tests or non-parametric alternatives. RESULTS: We found that 12-24-week active product intake increased plasma and/or erythrocyte micronutrients: uridine; choline; selenium; folate; vitamins B6, B12 and E; and fatty acid levels of DHA and EPA (all p < 0.001). In the OLE study, similar levels were reached in former control product/initial active product users, whereas 24-week continued active product intake showed no suggestion of a further increase in nutrient levels. CONCLUSIONS: These data show that circulating levels of nutrients known to be decreased in the AD population can be increased in patients with mild and mild-tomoderate AD by 24-48-week oral supplementation with Souvenaid. In addition, to our knowledge, this is the first report of the effects of sustained dietary intake of uridine monophosphate on plasma uridine levels in humans. Uptake of nutrients is observed within 6 weeks, and a plateau phase is reached for most nutrients during prolonged intake, thus increasing the availability of precursors and cofactors in the circulation that may be used for the formation and function of neuronal membranes and synapses in the brain.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/dietoterapia , Suplementos Nutricionais , Ácidos Graxos/sangue , Alimentos Formulados , Micronutrientes/sangue , Idoso , Método Duplo-Cego , Feminino , Humanos , Inflamação/sangue , Masculino , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/fisiologia , Índice de Gravidade de Doença , Resultado do Tratamento
11.
PLoS One ; 8(9): e75393, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24086523

RESUMO

Recent studies have focused on the use of multi-nutrient dietary interventions in search of alternatives for the treatment and prevention of Alzheimer's disease (AD). In this study we investigated to which extent long-term consumption of two specific multi-nutrient diets can modulate AD-related etiopathogenic mechanisms and behavior in 11-12-month-old AßPPswe-PS1dE9 mice. Starting from 2 months of age, male AßPP-PS1 mice and wild-type littermates were fed either a control diet, the DHA+EPA+UMP (DEU) diet enriched with uridine monophosphate (UMP) and the omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), or the Fortasyn® Connect (FC) diet enriched with the DEU diet plus phospholipids, choline, folic acid, vitamins and antioxidants. We performed behavioral testing, proton magnetic resonance spectroscopy, immunohistochemistry, biochemical analyses and quantitative real-time PCR to gain a better understanding of the potential mechanisms by which these multi-nutrient diets exert protective properties against AD. Our results show that both diets were equally effective in changing brain fatty acid and cholesterol profiles. However, the diets differentially affected AD-related pathologies and behavioral measures, suggesting that the effectiveness of specific nutrients may depend on the dietary context in which they are provided. The FC diet was more effective than the DEU diet in counteracting neurodegenerative aspects of AD and enhancing processes involved in neuronal maintenance and repair. Both diets elevated interleukin-1ß mRNA levels in AßPP-PS1 and wild-type mice. The FC diet additionally restored neurogenesis in AßPP-PS1 mice, decreased hippocampal levels of unbound choline-containing compounds in wild-type and AßPP-PS1 animals, suggesting diminished membrane turnover, and decreased anxiety-related behavior in the open field behavior. In conclusion, the current data indicate that specific multi-nutrient diets can influence AD-related etiopathogenic processes. Intervention with the FC diet might be of interest for several other neurodegenerative and neurological disorders.


Assuntos
Doença de Alzheimer/dietoterapia , Doença de Alzheimer/prevenção & controle , Encéfalo/metabolismo , Cognição/fisiologia , Alimentos Fortificados/análise , Análise de Variância , Animais , Encéfalo/efeitos dos fármacos , Colesterol/sangue , Cognição/efeitos dos fármacos , Primers do DNA/genética , Ácidos Docosa-Hexaenoicos , Ácido Eicosapentaenoico , Ácidos Graxos/metabolismo , Imuno-Histoquímica , Interleucina-1beta/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Mutantes , Reação em Cadeia da Polimerase em Tempo Real , Uridina Monofosfato
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