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1.
Front Oncol ; 14: 1404706, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38817905

RESUMO

Background: Operable triple-negative breast cancer (TNBC) is an unfavorable subtype of breast cancer, which usually requires an aggressive perioperative systemic treatment. When TNBC presents as a second primary cancer after cured acute leukemia, its management might be challenging. Case presentation: We present a case report of a young postmenopausal woman with an operable TNBC who had a history of the B-cell acute lymphoblastic leukemia (B-ALL) and graft versus host disease (GVHD) after allogeneic stem cell transplantation (allo-SCT). A history of previous treatment with anthracyclines and radiotherapy and GVHD limited the use of doxorubicin for treatment of her TNBC. Due to the history of GVHD, perioperative treatment with pembrolizumab was omitted. Genetic testing was challenging due to the possible contamination of her tissues with the donor's cells after allo-SCT. In samples of our patient's buccal swab, peripheral blood, and tumor tissue, a pathogenic variant in the partner and localizer of BRCA2 (PALB2) gene was found. With neoadjuvant chemotherapy which included carboplatin, a pathologic complete response was achieved. Although our patient has a low risk for recurrence of TNBC, her risk for the development of new primary cancers remains substantial. Conclusion: This case highlights challenges in the systemic treatment, genetic testing, and follow-up of patients with operable TNBC and other solid cancers who have a history of acute leukemia.

2.
J Geriatr Oncol ; 14(7): 101594, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37482497

RESUMO

INTRODUCTION: Sarcopenia is a common skeletal muscle disorder in older people. Here we explore the prevalence of sarcopenia and its impact on men with prostate cancer. MATERIALS AND METHODS: We searched PubMed, Embase, and Web of Science databases for relevant studies with an explicit definition of sarcopenia in men with prostate cancer which were published between years 2000 and 2022. Prevalence of sarcopenia and its association with time to biochemical recurrence (BCR), progression-free survival (PFS), non-cancer mortality, overall survival (OS), and treatment-related complications in men with prostate cancer were explored. The summary prevalence, hazard ratios (HRs), and 95% confidence intervals (CIs) were calculated. RESULTS: A total of 24 studies comprising 3,616 patients with early and advanced prostate cancer were included. The prevalence of sarcopenia and sarcopenic obesity was 43.8% (95% CI 19.2%-68.5%) and 24.0% (95% CI 5.0%-43.1%), respectively. Sarcopenia was not associated with a shorter time to BCR (HR 0.89, 95% CI 0.64-1.23, p = 0.48), a shorter PFS (HR 1.20, 95% CI 0.73-1.97, p = 0.48), or a shorter OS (HR 1.29, 95% CI 0.90-1.85, p = 0.16). In contrast, sarcopenia was significantly associated with a higher non-cancer mortality (HR 1.85, 95% CI 1.23-2.80, p = 0.003). In four out of five studies eligible for assessment, sarcopenia was not associated with an increased risk of treatment-related complications. DISCUSSION: Sarcopenia increases the risk of death from other causes in men with prostate cancer. Patients with prostate cancer should be assessed and managed for sarcopenia in everyday clinical practice.


Assuntos
Neoplasias da Próstata , Sarcopenia , Masculino , Humanos , Idoso , Sarcopenia/complicações , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/complicações , Obesidade/complicações , Modelos de Riscos Proporcionais , Prognóstico
3.
J Magn Reson ; 310: 106649, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31778887

RESUMO

A method for characterising water and oil in a rock core plug using correlations between diffusion decay in internal magnetic gradient and transverse relaxation time (DG02-T2) is presented. The method is evaluated at different saturation levels and is compared with the measurement of correlations between diffusion and transverse relaxation time (D-T2). It is shown how signals from water and oil can be separated based on their difference in diffusion decay in internal gradients. The obtained results show that the impact from heterogeneity in pore geometry and mineralogy on the individual liquids is revealed in more detail in DG02-T2 correlations compared to the more established D-T2 correlations. Measurements of DG02-T2 correlations should be included in the toolbox of NMR experiments performed in the laboratory analysis of rock core plugs, and could then potentially lead to more detailed estimations of saturation levels and surface wettability properties.

4.
Acta Physiol (Oxf) ; 225(3): e13199, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30300965

RESUMO

AIM: Epac1-/- mice, but not Epac2-/- mice have elevated baseline permeability to albumin. This study extends the investigations of how Epac-dependent pathways modulate transvascular exchange in response to the classical inflammatory agent histamine. It also evaluates the limitations of models of blood-to-tissue exchange in transgenic mice in DCE-MRI measurements. METHODS: We measured DCE-MRI signal intensity in masseter muscle of wt and Epac1-/- mice with established approaches from capillary physiology to determine how changes in blood flow and vascular permeability contribute to overall changes of microvascular flux. We used two tracers, the high molecular weight tracer (Gadomer-17, MW 17 kDa, apparent MW 30-35 kDa) is expected to be primarily limited by diffusion and therefore less dependent on changes in blood flow and the low molecular weight tracer (Dotarem (MW 0.56 kDa) whose transvascular exchange is determined by both blood flow and permeability. Paired experiments in each animal combined with analytical methods provided an internally consistent description of microvascular transport. RESULTS: Epac1-/- mice had elevated baseline permeability relative to wt control mice for Dotarem and Gadomer-17. In contrast to wt mice, Epac1-/- mice failed to increase transvascular permeability in response to histamine. Dotarem underestimated blood flow and vascular volume and Gadomer-17 has limited sensitivity in extravascular accumulation. CONCLUSION: The study suggests that the normal barrier loosening effect of histamine in venular microvessels do not function when the normal barrier tightening effect of Epac1 is already compromised. The study also demonstrated that the numerical analysis of DCE-MRI data with tracers of different molecular weight has significant limitations.


Assuntos
Permeabilidade Capilar/fisiologia , Fatores de Troca do Nucleotídeo Guanina/deficiência , Histamina/metabolismo , Imageamento por Ressonância Magnética , Peso Molecular , Animais , Meios de Contraste/metabolismo , Imageamento por Ressonância Magnética/métodos , Camundongos Knockout , Microvasos/metabolismo
5.
Magn Reson Imaging ; 46: 10-20, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29066294

RESUMO

OBJECTIVE: An extension of single- and multi-channel blind deconvolution is presented to improve the estimation of the arterial input function (AIF) in quantitative dynamic contrast enhanced magnetic resonance imaging (DCE-MRI). METHODS: The Lucy-Richardson expectation-maximization algorithm is used to obtain estimates of the AIF and the tissue residue function (TRF). In the first part of the algorithm, nonparametric estimates of the AIF and TRF are obtained. In the second part, the decaying part of the AIF is approximated by three decaying exponential functions with the same delay, giving an almost noise free semi-parametric AIF. Simultaneously, the TRF is approximated using the adiabatic approximation of the Johnson-Wilson (aaJW) pharmacokinetic model. RESULTS: In simulations and tests on real data, use of this AIF gave perfusion values close to those obtained with the corresponding previously published nonparametric AIF, and are more noise robust. CONCLUSION: When used subsequently in voxelwise perfusion analysis, these semi-parametric AIFs should give more correct perfusion analysis maps less affected by recording noise than the corresponding nonparametric AIFs, and AIFs obtained from arteries. SIGNIFICANCE: This paper presents a method to increase the noise robustness in the estimation of the perfusion parameter values in DCE-MRI.


Assuntos
Meios de Contraste/farmacocinética , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Algoritmos , Animais , Artérias/patologia , Simulação por Computador , Meios de Contraste/química , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Perfusão , Reprodutibilidade dos Testes
6.
PLoS One ; 10(8): e0135220, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26252891

RESUMO

BACKGROUND: Orthotopic endometrial cancer models provide a unique tool for studies of tumour growth and metastatic spread. Novel preclinical imaging methods also have the potential to quantify functional tumour characteristics in vivo, with potential relevance for monitoring response to therapy. METHODS: After orthotopic injection with luc-expressing endometrial cancer cells, eleven mice developed disease detected by weekly bioluminescence imaging (BLI). In parallel the same mice underwent positron emission tomography-computed tomography (PET-CT) and magnetic resonance imaging (MRI) employing 18F-fluorodeoxyglocose (18F-FDG) or 18F- fluorothymidine (18F-FLT) and contrast reagent, respectively. The mice were sacrificed when moribund, and post-mortem examination included macroscopic and microscopic examination for validation of growth of primary uterine tumours and metastases. PET-CT was also performed on a patient derived model (PDX) generated from a patient with grade 3 endometrioid endometrial cancer. RESULTS: Increased BLI signal during tumour growth was accompanied by increasing metabolic tumour volume (MTV) and increasing MTV x mean standard uptake value of the tumour (SUVmean) in 18F-FDG and 18F-FLT PET-CT, and MRI conspicuously depicted the uterine tumour. At necropsy 82% (9/11) of the mice developed metastases detected by the applied imaging methods. 18F-FDG PET proved to be a good imaging method for detection of patient derived tumour tissue. CONCLUSIONS: We demonstrate that all imaging modalities enable monitoring of tumour growth and metastatic spread in an orthotopic mouse model of endometrial carcinoma. Both PET tracers, 18F-FDG and 18F-FLT, appear to be equally feasible for detecting tumour development and represent, together with MRI, promising imaging tools for monitoring of patient-derived xenograft (PDX) cancer models.


Assuntos
Carcinoma/patologia , Neoplasias do Endométrio/patologia , Imagem Multimodal , Idoso , Animais , Linhagem Celular Tumoral , Meios de Contraste , Didesoxinucleosídeos/química , Modelos Animais de Doenças , Progressão da Doença , Feminino , Fluordesoxiglucose F18/química , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Metástase Neoplásica , Transplante de Neoplasias , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X
7.
Undersea Hyperb Med ; 42(1): 57-64, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26094305

RESUMO

AIMS: The main objectives of the present study was to establish an animal model of decompression sickness (DCS) after heliox saturation diving, and to use this model to evaluate possible morphological changes in the CNS induced by DCS using structural MRI. METHODS: Two groups of rats were pressurized with heliox to 5 bar (pO2 = 50 kPa). The saturation time was three hours; decompression rate was 1 bar/10 seconds or 1 bar/20 seconds. A 7.0 Tesla small animal MRI scanner was used for detection of possible morphological changes in the brain and spinal cord, two hours and one week after the dive, compared to one week prior to the dive. RESULTS: Neurological symptoms of DCS were observed in seven out of 10 animals. MRI of the brain and spinal cord did not reveal any morphological CNS injuries. CONCLUSION: This diving procedure was successful in causing DCS in a large proportion of the animals. However, despite massive neurological signs of DCS, no visible CNS injuries were observed in the MRI scans.


Assuntos
Encéfalo/patologia , Doença da Descompressão/patologia , Modelos Animais de Doenças , Hélio , Oxigênio , Medula Espinal/patologia , Animais , Descompressão/métodos , Doença da Descompressão/etiologia , Doença da Descompressão/terapia , Feminino , Síndrome Neurológica de Alta Pressão/etiologia , Oxigenoterapia Hiperbárica , Imageamento por Ressonância Magnética , Pressão Parcial , Ratos , Ratos Wistar
8.
Adv Drug Deliv Rev ; 76: 98-115, 2014 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-25078721

RESUMO

The vast majority of malignant gliomas relapse after surgery and standard radio-chemotherapy. Novel molecular and cellular therapies are thus being developed, targeting specific aspects of tumor growth. While histopathology remains the gold standard for tumor classification, neuroimaging has over the years taken a central role in the diagnosis and treatment follow up of brain tumors. It is used to detect and localize lesions, define the target area for biopsies, plan surgical and radiation interventions and assess tumor progression and treatment outcome. In recent years the application of novel drugs including anti-angiogenic agents that affect the tumor vasculature, has drastically modulated the outcome of brain tumor imaging. To properly evaluate the effects of emerging experimental therapies and successfully support treatment decisions, neuroimaging will have to evolve. Multi-modal imaging systems with existing and new contrast agents, molecular tracers, technological advances and advanced data analysis can all contribute to the establishment of disease relevant biomarkers that will improve disease management and patient care. In this review, we address the challenges of glioma imaging in the context of novel molecular and cellular therapies, and take a prospective look at emerging experimental and pre-clinical imaging techniques that bear the promise of meeting these challenges.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Glioma/diagnóstico , Glioma/terapia , Imagem Multimodal , Animais , Terapia Baseada em Transplante de Células e Tecidos , Humanos , Terapia de Alvo Molecular , Neuroimagem
9.
Cancer Res ; 73(4): 1276-86, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23233739

RESUMO

The ability to visualize reporter gene expression in vivo has revolutionized all facets of biologic investigation and none more so than imaging applications in oncology. Near-infrared reporter gene imaging may facilitate more accurate evaluation of chemotherapeutic response in preclinical models of orthotopic and metastatic cancers. We report the development of a cell permeable, quenched squarine probe (CytoCy5S), which is reduced by Escherichia coli nitroreductase (NTR), resulting in a near-infrared fluorescent product. Time-domain molecular imaging of NTR/CytoCy5S reporter platform permitted noninvasive monitoring of disease progression in orthotopic xenografts of disseminated leukemia, lung, and metastatic breast cancer. This methodology facilitated therapeutic evaluation of NTR gene-directed enzymatic prodrug therapy with conventional metronidazole antibiotics. These studies show NTR/CytoCy5S as a near-infrared gene reporter system with broad preclinical and prospective clinical applications within imaging, and gene therapy, of cancer.


Assuntos
Carbocianinas/metabolismo , Neoplasias/metabolismo , Nitrorredutases/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Anti-Infecciosos/farmacologia , Carbocianinas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Luciferases/genética , Luciferases/metabolismo , Imageamento por Ressonância Magnética/métodos , Metronidazol/metabolismo , Metronidazol/farmacologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Microscopia de Fluorescência/métodos , Metástase Neoplásica , Neoplasias/tratamento farmacológico , Neoplasias/genética , Nitroimidazóis/metabolismo , Nitroimidazóis/farmacologia , Nitrorredutases/química , Nitrorredutases/genética , Reprodutibilidade dos Testes , Transfecção
10.
PLoS One ; 8(12): e84162, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24386344

RESUMO

In multiple sclerosis (MS), the correlation between lesion load on conventional magnetic resonance imaging (MRI) and clinical disability is weak. This clinico-radiological paradox might partly be due to the low sensitivity of conventional MRI to detect gray matter demyelination. Magnetization transfer ratio (MTR) has previously been shown to detect white matter demyelination in mice. In this study, we investigated whether MTR can detect gray matter demyelination in cuprizone exposed mice. A total of 54 female C57BL/6 mice were split into one control group () and eight cuprizone exposed groups ([Formula: see text]). The mice were exposed to [Formula: see text] (w/w) cuprizone for up to six weeks. MTR images were obtained at a 7 Tesla Bruker MR-scanner before cuprizone exposure, weekly for six weeks during cuprizone exposure, and once two weeks after termination of cuprizone exposure. Immunohistochemistry staining for myelin (anti-Proteolopid Protein) and oligodendrocytes (anti-Neurite Outgrowth Inhibitor Protein A) was obtained after each weekly scanning. Rates of MTR change and correlations between MTR values and histological findings were calculated in five brain regions. In the corpus callosum and the deep gray matter a significant rate of MTR value decrease was found, [Formula: see text] per week ([Formula: see text]) and [Formula: see text] per week ([Formula: see text]) respectively. The MTR values correlated to myelin loss as evaluated by immunohistochemistry (Corpus callosum: [Formula: see text]. Deep gray matter: [Formula: see text]), but did not correlate to oligodendrocyte density. Significant results were not found in the cerebellum, the olfactory bulb or the cerebral cortex. This study shows that MTR can be used to detect demyelination in the deep gray matter, which is of particular interest for imaging of patients with MS, as deep gray matter demyelination is common in MS, and is not easily detected on conventional clinical MRI.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Cuprizona/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/patologia , Imageamento por Ressonância Magnética , Animais , Doenças Desmielinizantes/diagnóstico , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Tempo
11.
Int J Neuropsychopharmacol ; 15(2): 163-79, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21854679

RESUMO

Metabolic adverse effects such as weight gain and dyslipidaemia represent a major concern in treatment with several antipsychotic drugs, including olanzapine. It remains unclear whether such metabolic side-effects fully depend on appetite-stimulating actions, or whether some dysmetabolic features induced by antipsychotics may arise through direct perturbation of metabolic pathways in relevant peripheral tissues. Recent clinical and preclinical studies indicate that dyslipidaemia could occur independently of weight gain. Using a rat model, we showed that subchronic treatment with olanzapine induces weight gain and increases adipose tissue mass in rats with free access to food. This effect was also observed for aripiprazole, considered metabolically neutral in the clinical setting. In pair-fed rats with limited food access, neither olanzapine nor aripiprazole induced weight gain. Interestingly, olanzapine, but not aripiprazole, induced weight-independent elevation of serum triglycerides, accompanied by up-regulation of several genes involved in lipid biosynthesis, both in liver and in adipose tissues. Our findings support the existence of tissue-specific, weight-independent direct effects of olanzapine on lipid metabolism.


Assuntos
Antipsicóticos/farmacologia , Benzodiazepinas/farmacologia , Lipogênese/efeitos dos fármacos , Piperazinas/farmacologia , Quinolonas/farmacologia , Triglicerídeos/sangue , Aumento de Peso/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Antipsicóticos/toxicidade , Aripiprazol , Benzodiazepinas/toxicidade , Peso Corporal/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica , Hiperfagia/sangue , Hiperfagia/induzido quimicamente , Metabolismo dos Lipídeos/efeitos dos fármacos , Olanzapina , Piperazinas/toxicidade , Quinolonas/toxicidade , Ratos , Ratos Sprague-Dawley
12.
Lab Anim ; 45(1): 31-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21047888

RESUMO

Non-invasive imaging methods like echocardiography and magnetic resonance imaging (MRI) are very valuable in longitudinal follow-up studies of cardiac function in small animals. To be able to compare results from studies using different methods, and explain possible differences, it is important to know the agreement between these methods. As both self-gated high-field MRI and high-frequency echocardiography (hf-echo) M-mode are potential methods for evaluation of left ventricular (LV) function in healthy mice, our aim was to assess the agreement between these two methods. Fifteen healthy female C57BL/6J mice underwent both self-gated MRI and hf-echo during the same session of light isoflurane anaesthesia. LV dimensions were estimated offline, and agreement between the methods and reproducibility for the two methods assessed using Bland-Altman methods. In summary, hf-echo M-mode had better inter-observer repeatability than self-gated MRI for all measured parameters. Compared with hf-echo, systolic posterior wall thicknesses were significantly higher when measured by MRI, while diastolic anterior wall thicknesses were found to be significantly smaller. MRI measurements of diastolic LV diameter were also higher using MRI, resulting in larger fractional shortening values compared with the values obtained by hf-echo. In conclusion, hf-echo M-mode is easy to apply, has high temporal and spatial resolution, and good reproducibility. Self-gated MRI might be advantageous in cases of abnormal LV geometry and heterogeneous regional myocardial function, especially with improvements in spatial resolution. The moderate agreement between the methods must be taken into account when comparing studies using the two modalities.


Assuntos
Ecocardiografia/métodos , Imagem Cinética por Ressonância Magnética/métodos , Imagem Cinética por Ressonância Magnética/veterinária , Camundongos , Anestesia por Inalação/veterinária , Anestésicos Inalatórios/farmacologia , Animais , Ecocardiografia/instrumentação , Ecocardiografia/veterinária , Feminino , Cardiopatias/diagnóstico , Isoflurano , Imagem Cinética por Ressonância Magnética/instrumentação , Camundongos Endogâmicos C57BL , Modelos Animais , Distribuição Aleatória , Reprodutibilidade dos Testes , Função Ventricular Esquerda
13.
Magn Reson Imaging ; 23(2): 329-31, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15833638

RESUMO

In this work we present measurements of permeability, effective porosity and tortuosity on a variety of rock samples using NMR/MRI of thermal and laser-polarized gas. Permeability and effective porosity are measured simultaneously using MRI to monitor the inflow of laser-polarized xenon into the rock core. Tortuosity is determined from measurements of the time-dependent diffusion coefficient using thermal xenon in sealed samples. The initial results from a limited number of rocks indicate inverse correlations between tortuosity and both effective porosity and permeability. Further studies to widen the number of types of rocks studied may eventually aid in explaining the poorly understood connection between permeability and tortuosity of rock cores.


Assuntos
Espectroscopia de Ressonância Magnética , Permeabilidade , Isótopos de Xenônio , Fenômenos Geológicos , Geologia , Porosidade
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