Imagem longitudinal é usada em estudos pré-clínicos para acompanhar o progresso de uma doença ou medir o efeito de uma terapêutica. Em oncologia, métodos ópticos fornecem ferramentas rigorosa para monitorar o crescimento do tumor e entregar quantificação precisa do crescimento celular ou a expressão de genes em cada momento em tal estudo. Alterações anatômicas pode ser medida utilizando uma técnica de alta resolução, como microCT, mas para imagens longitudinal uma dose de raios-X de baixa deve ser usado para evitar artefatos biológicos. Imagens ópticas e microCT pode ser co-registrados para fornecer uma combinação de dados anatômicos e funcionais garantir que o máximo de informação é extraída do modelo animal. 1. Preparação celular <ol><li> Caliper fornece uma gama de luciferase linhas expressando câncer de células para pesquisa pré-clínica em modelos de mouse. </li><li> MDA-MB-231-luc-D2H2LN é uma linha de células mamárias humanas tumor expressando o gene da luciferase, que pode ser usado como um indicador óptico de tumorgenesis in vivo. Esta linhagem celular é criado a partir de uma metástase ganglionar espontânea que se originou a partir de um tumor mamário pad D3H1 gordura e é conhecido de forma agressiva formar metástases. </li><li> As células são fornecidos como uma cultura isentos de agentes patogénicos congelados que prontamente cresce em mídia padrão sem a necessidade de marcadores de seleção. </li><li> Para verificar a atividade luciferase antes da injeção no animal um frasco de 90% confluentes é colhido por tripsinização. Atividade de luciferase é medido por dispensar 50.000 células em uma placa de microtitulação e execução de diluição serial. </li></ol> 2. Intracardíaca injeção de células em animais <ol><li> Antes da injeção, os animais são anestesiados com isoflurano 3%. </li><li> 1-3000000 células são injetadas no volume 50uL para o ventrículo esquerdo. Suspensão de células contém 150ug/ml D-Luciferina para validar a técnica de injecção. </li><li> Para confirmar uma injeção de ratos correta intracardíacas são gravadas no sistema IVIS. Ratos que mostram sinal de BLI por todo o corpo ter sido injetado corretamente. Se o sinal está localizada as células não foram injetados corretamente no coração. </li></ol> 3. BLI imagem para monitorar metástases <ol><li> O shuttle imaging suporta o mouse para captura de dados em ambos os Spectrum IVIS eo QuantumFX sistema microCT. </li><li> O ônibus ajuda a manter o animal na mesma posição para imagens e incorpora sinais fiducial para ajudar na automática co-registro. A câmara é ligada ao vaporizador isofluorance para manter a anestesia. </li><li> Assistente de imagem no software Image Vivendo 4.1 pode ser usado para selecionar automaticamente o tempo de exposição, f-stop e binning e garantir a coleta de dados quantitativos. </li><li> Várias imagens podem ser adquiridos e comparados em estudos longitudinais que cobrem segundos ou meses, dependendo da natureza do experimento. </li><li> Dia pós-injeção de células 6, BLI imagem com IVIS Spectrum mostra metástases para o osso em sete dos nove camundongos. </li></ol> 4. Acompanhamento longitudinal de lesões osteolíticas usando micro CT <ol><li> Os ratos que mostraram metástases ósseas claro e visível usando BLI foram fotografadas no micro FX Quantum sistema de CT. </li><li> O Quantum FX micro sistema de CT fornece imagens de alta qualidade a uma dose de raios-X de baixa o suficiente para permitir verdadeira longitudinal micro CT em estudos pré-clínicos. </li><li> Degradação óssea em ambas as pernas podem ser monitorados longitudinalmente usando este sistema em menos de um minuto. </li><li> Os ratos são anestesiados com isoflurano 3% e podem ser transferidos diretamente do sistema Spectrum IVIS. </li><li> Duas imagens de 60 milímetros são costuradas juntas para capturar o ponto de vista animal inteiro. </li><li> A FOV 30mm é ideal para imagens de joelho em alta resolução. </li><li> A única digitalização com resolução alta o suficiente para medir e quantificar metástases ósseas leva apenas 18 segundos e oferece uma dose de apenas 13mGy. </li><li> Camundongos foram fotografadas até 8 vezes em 36 dias com o sistema de CT micro, sem afetar o crescimento do tumor ou a saúde do animal. </li><li> O micro tomografia computadorizada mostrou que leisions óssea foram visíveis no dia 10 e progrediu muito rapidamente, o que corresponde ao aumento do sinal de BLI. </li></ol> 5. 3D co-registro e análise de BLI e UCT <ol><li> Uma vez que as imagens foram capturadas em ambos o espectro IVIS e FX Quantum micro dados CT sistema pode ser co-registrados em uma reconstrução 3D. </li><li> MicroCT imagens são exportadas como arquivos DICOM e carregado na ferramenta imagem viva modalidade 4,1 3D Multi. </li><li> No Software imagem viva executar o programa DLIT a três dimensões reconstruir o sinal óptico. </li><li> A ferramenta de referência no software é usado para co-registrar o sinal de BLI óptica para a imagem CT micro. </li><li> Conjuntos de co-registrados os dados podem ser analisados ​​quantitativamente para monitorar vários parâmetros durante a progressão da doença aqui estamos acompanhando o crescimento do tumor metastático juntamente com o desenvolvimento da lesão osteolítica no osso. </li> &lt;/ Ol&gt;

<ol>
	<li>Jenkins, D. E., Hornig, Y. S., Oei, Y., Dusich, J., Purchio, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bioluminescent+Human+Breast+Cancer+Cell+Lines+that+Permit+Rapid+and+Sensitive+in+vivo+Detection+of+Mammary+Tumors+and+Multiple+Metastases+in+Immune+Deficient+Mice.">Bioluminescent Human Breast Cancer Cell Lines that Permit Rapid and Sensitive in vivo Detection of Mammary Tumors and Multiple Metastases in Immune Deficient Mice.</a> Breast Cancer Research. 7, R444-R454 (2005).</li><li>Cowey, S., Szafran, A. A., Kappes, J., Zinn, K. R., Siegal, G. P., Desmond, R. A., Kim, H., Evans, L., Hardy, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Breast+Cancer+Metastasis+to+Bone:+Evaluation+of+Bioluminescent+Imaging+and+MicroSPECT/CT+for+Detecting+Bone+Metastasis+in+Immunodeficient+Mice.">Breast Cancer Metastasis to Bone: Evaluation of Bioluminescent Imaging and MicroSPECT/CT for Detecting Bone Metastasis in Immunodeficient Mice.</a> Clinical and Experimental Metastasis. 24, 389-401 (2007).</li><li>Labrinidis, A., Hay, S., Liapis, V., Ponomarev, V., Findlay, D. M., Evdokiou, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Zoledronic+Acid+Inhibits+Both+the+Osteolytic+and+Osteoblastic+Components+of+Osteosarcoma+Lesions+in+a+Mouse+Model.">Zoledronic Acid Inhibits Both the Osteolytic and Osteoblastic Components of Osteosarcoma Lesions in a Mouse Model.</a> Clinical Cancer Research. 15, (2009).</li><li>Kaijzel, E. L., Pluijm, G. v. a. n. d. e. r., Lowik, C. W. G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Whole-Body+Optical+Imaging+in+Animal+Models+to+Assess+Cancer+Development+and+Progression.">Whole-Body Optical Imaging in Animal Models to Assess Cancer Development and Progression.</a> Clinical Cancer Research. 13, 3490-3497 (2007).</li><li>Minn, A. J., Kang, Y., Serganova, I., Gupta, G. P., Giri, D. D., Doubrovin, M., Ponomarev, V., Gerald, W. L., Blasberg, R., Massague, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distinct+Organ-Specific+Metastatic+Potential+of+Individual+Breast+Cancer+Cells+and+Primary+Tumors.">Distinct Organ-Specific Metastatic Potential of Individual Breast Cancer Cells and Primary Tumors.</a> The Journal of Clinical Investigation. 115, (2005).</li><li>Xu, H., Christensen, A., Kuo, C., Nilson, D., Lim, E., Whalen, J., Kim, J. B., Zhang, N., Singh, R., Oldfield, S., Troy, T., Rice, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Co-registration+of+in+vivo+Optical+Tomography+and+Micro-CT+for+Longitudinal+Studies.">Co-registration of in vivo Optical Tomography and Micro-CT for Longitudinal Studies.</a> Word Molecular Imaging Congress. , (2010).</li></ol>

Os autores são funcionários da Caliper Life Sciences que fazem o instrumento apresentado neste artigo.

Imagem de pequenos animais com microCT tem sido aplicada ao monitoramento lesões osteolíticas em condições patológicas, como o desenvolvimento do tumor (Cowey et al 2007;.. Labrinidis et al, 2009). Como imagem de bioluminescência de luciferase tumores marcada tem sido amplamente adotado pré-clínica, co-registro de imagens bioluminescência e microCT proporcionou uma melhor definição da localização anatômica dos sinais de bioluminescência (Kaijzel et al. 2007). Estudo anterior com um rótulo de linha de mama luciferase das células tumorais MDA-MB-231-luc-D3H2LN mostrou metástases para osso e desenvolvimento de lesões osteolíticas seguintes injeção intra-cardíaca (Jenkins et al 2005;. Minn et al, 2005). Neste estudo, exploramos um estudo longitudinal de metástases do tumor e atividade osteolítica com combinatória óptica e baixa dose de radiação de imagens microCT com o modelo de metástase sistêmica MDA-MB-231-luc-D3H2LN. Realizamos imagem seqüencial com IVIS Spectrum e FX Quantum microCT sistemas e bioluminescência alcançados e CT co-registro com a nossa imagem viva recentemente desenvolvido 4,1 software (Heng et al., 2010). Imagem de bioluminescência com IVIS fornece não-invasivo de detecção das células tumorais com alta sensibilidade, permitindo que os tumores para ser detectado em fase inicial. Imagem com Quantum FX permite a reconstrução 3D preciso das lesões ósseas e informações anatômicas detalhadas. Quantum FX sistema oferece imagem baixa dose de radiação, que permite o monitoramento longitudinal da progressão da doença. Correlação de lesões ósseas e metástases tumorais foi representado na imagem co-registrados, ea vantagem de rastreamento multimodalidade de desenvolvimento da lesão longitudinal foi claramente demonstrado.

monitoring tumor metastases and osteolytic lesions with bioluminescence and micro ct imaging

Entrega intracardíaca seguintes MDA-MB-231-luc-D3H2LN células para Nu / Nu camundongos, metástases sistêmicas desenvolveram nos animais injetados. Imagem de bioluminescência usando Spectrum IVIS foi empregado para monitorar a distribuição e desenvolvimento das células tumorais após o procedimento de entrega, incluindo a reconstrução DLIT para medir o sinal de tumor e sua localização. Desenvolvimento de lesões metastáticas para os tecidos ósseos desencadeia a atividade osteolítica e lesões à tíbia e fêmur foram avaliados longitudinalmente usando micro CT. De imagem foi realizado utilizando um sistema de micro Quantum FX CT com imagens rápidas e dose de raios-X de baixa. A baixa dose de radiação permite múltiplas sessões de imagem a ser realizada com uma dosagem de raios-X cumulativo muito abaixo LD50. Um rato dispositivo de transporte de imagens foi usado para seqüencialmente imagem os ratos com ambos IVIS Spectrum e FX Quantum alcançar o posicionamento exato de animais em ambos os bioluminescência e imagens de TC. O óptico e define CT dados foram co-registradas em 3-dimentions usando a imagem viva 4,1 software. Esta abordagem multi-modo permite acompanhar de perto o crescimento do tumor e do desenvolvimento simultâneo com a atividade osteolítica.

Watch this Scientific Journal Video about Monitoring Tumor Metastases and Osteolytic Lesions with Bioluminescence and Micro CT Imaging at JoVE.com

Monitoring Tumor Metastases and Osteolytic Lesions with Bioluminescence and Micro CT Imaging

Um modelo de camundongo experimental de metástase óssea foi estabelecido após a entrega intracardíaca da luciferase expressando células tumorais mamárias. Desenvolvimento do tumor e resultou lesão osteolítica foram monitorados longitudinalmente, com a bioluminescência e CT micro imagem.

Monitoramento metástases tumorais e lesões osteolíticas com bioluminescência e CT Micro Imagem

Following intracardiac delivery of MDA-MB-231-luc-D3H2LN cells to Nu/Nu mice, systemic metastases developed in the injected animals. Bioluminescence ...

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Medicine

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Vídeo: Monitoring Tumor Metastases and Osteolytic Lesions with Bioluminescence and Micro CT Imaging

In vivo Bioluminescence Imaging of Tumor Hypoxia Dynamics of Breast Cancer Brain Metastasis in a Mouse Model

It is well recognized that tumor hypoxia plays an important role in promoting malignant progression and affecting therapeutic response negatively. There is little knowledge about in situ, in vivo, tumor hypoxia during intracranial development of malignant brain tumors because of lack of efficient means to monitor it in these deep-seated orthotopic tumors. Bioluminescence imaging (BLI), based on the detection of light emitted by living cells expressing a luciferase gene, has been rapidly adopted for cancer research, in particular, to evaluate tumor growth or tumor size changes in response to treatment in preclinical animal studies. Moreover, by expressing a reporter gene under the control of a promoter sequence, the specific gene expression can be monitored non-invasively by BLI. Under hypoxic stress, signaling responses are mediated mainly via the hypoxia inducible factor-1&alpha; (HIF-1&alpha;) to drive transcription of various genes. Therefore, we have used a HIF-1&alpha; reporter construct, 5HRE-ODD-luc, stably transfected into human breast cancer MDA-MB231 cells (MDA-MB231/5HRE-ODD-luc). In vitro HIF-1&alpha; bioluminescence assay is performed by incubating the transfected cells in a hypoxic chamber (0.1% O2) for 24 hr before BLI, while the cells in normoxia (21% O2) serve as a control. Significantly higher photon flux observed for the cells under hypoxia suggests an increased HIF-1&alpha; binding to its promoter (HRE elements), as compared to those in normoxia. Cells are injected directly into the mouse brain to establish a breast cancer brain metastasis model. In vivo bioluminescence imaging of tumor hypoxia dynamics is initiated 2 wks after implantation and repeated once a week. BLI reveals increasing light signals from the brain as the tumor progresses, indicating increased intracranial tumor hypoxia. Histological and immunohistochemical studies are used to confirm the in vivo imaging results. Here, we will introduce approaches of in vitro HIF-1&alpha; bioluminescence assay, surgical establishment of a breast cancer brain metastasis in a nude mouse and application of in vivo bioluminescence imaging to monitor intracranial tumor hypoxia.

In vivo Bioluminescence Imaging of Tumor Hypoxia Dynamics of Breast Cancer Brain Metastasis in a Mouse Model

Bioluminescence imaging of hypoxia inducible factor-1&alpha; activity is applied to monitor intracranial tumor hypoxia development in a breast cancer brain metastasis mouse model.

Na imagem de bioluminescência vivo Tumor de mama Dynamics Hipóxia metástase do cancro cerebral em um modelo de rato

It is well recognized that tumor hypoxia plays an important role in promoting malignant progression and affecting therapeutic response negatively. There ...

Medicina

Osmotic Drug Delivery to Ischemic Hindlimbs and Perfusion of Vasculature with Microfil for Micro-Computed Tomography Imaging

Preclinical research in animal models of peripheral arterial disease plays a vital role in testing the efficacy of therapeutic agents designed to stimulate microcirculation. The choice of delivery method for these agents is important because the route of administration profoundly affects the bioactivity and efficacy of these agents1,2. In this article, we demonstrate how to locally administer a substance in ischemic hindlimbs by using a catheterized osmotic pump. This pump can deliver a fixed volume of aqueous solution continuously for an allotted period of time. We also present our mouse model of unilateral hindlimb ischemia induced by ligation of the common femoral artery proximal to the origin of profunda femoris and epigastrica arteries in the left hindlimb. Lastly, we describe the in vivo cannulation and ligation of the infrarenal abdominal aorta and perfusion of the hindlimb vasculature with Microfil, a silicone radiopaque casting agent. Microfil can perfuse and fill the entire vascular bed (arterial and venous), and because we have ligated the major vascular conduit for exit, the agent can be retained in the vasculature for future ex vivo imaging with the use of small specimen micro-CT3.

We show here the in vivo insertion of an osmotic pump for constant local drug delivery and the creation of hindlimb ischemia in a mouse model. Moreover, the hindlimb vasculature is perfused with Microfil, a silicone radiopaque agent, to prepare for micro-computed tomography (micro-CT) imaging.

Osmótica Drug Delivery para hindlimbs isquêmicos e perfusão da vasculatura com Microfil para Micro-tomografia computadorizada

Preclinical research in animal models of peripheral arterial disease plays a vital role in testing the efficacy of therapeutic agents designed to ...

Bioluminescence Imaging of an Immunocompetent Animal Model for Glioblastoma

In contrast to commonly reported human glioma xenograft animal models, GL261 murine glioma xenografts recapitulate nearly all relevant clinical and histopathologic features of the human disease. When GL261 cells are implanted intracranially in syngeneic C57BL/6 mice, the model has the added advantage of maintaining an intact immune microenvironment. Stable expression of luciferase in GL261 cells allows non-invasive cost effective bioluminescence monitoring of intracranial tumor growth. We have recently demonstrated that luciferase expression in GL261 cells does not affect the tumor growth properties, tumor cell immunomodulatory cytokine expression, infiltration of immune cells into the tumor, or overall survival of animals bearing the intracranial tumor. Therefore, it appears that the GL261 luciferase glioma model can be useful in the study of novel chemotherapeutic and immunotherapeutic modalities. Here we report the technique for generating stable luciferase expression in GL261 cells and how to study the in vitro and in vivo growth of the tumor cells by bioluminescence imaging.

GL261 glioma cells provide a useful immunocompetent animal model of glioblastoma. The goals of this protocol are to demonstrate proper techniques for monitoring intracranial tumor growth using in vivo bioluminescence imaging, and to verify the utility of luciferase-modified GL261 cells for studying tumor immunology and immunotherapeutic approaches for treating glioblastoma.

Bioluminescência imagem de um modelo animal para imunocompetentes Glioblastoma

In contrast to commonly reported human glioma xenograft animal models, GL261 murine glioma xenografts recapitulate nearly all relevant clinical and ...

Bioluminescence-Based Tumor Quantification Method for Monitoring Tumor Progression and Treatment Effects in Mouse Lymphoma Models

Although bioluminescence imaging (BLI) shows promise for monitoring tumor burden in animal models of cancer, these analyses remain mostly qualitative. Here we describe a method for bioluminescence imaging to obtain a semi-quantitative analysis of tumor burden and treatment response. This method is based on the calculation of a luminoscore, a value that allows comparisons of two animals from the same or different experiments. Current BLI instruments enable the calculation of this luminoscore, which relies mainly on the acquisition conditions (back and front acquisitions) and the drawing of the region of interest (manual markup around the mouse). Using two previously described mouse lymphoma models based on cell engraftment, we show that the luminoscore method can serve as a noninvasive way to verify successful tumor cell inoculation, monitor tumor burden, and evaluate the effects of in situ cancer treatment (CpG-DNA). Finally, we show that this method suits different experimental designs. We suggest that this method be used for early estimates of treatment response in preclinical small-animal studies.

Bioluminescence imaging is a well-known tool for localizing tumors and metastases, but quantification of these images often requires complex calculations and particular instruments. We describe the easy-to-use luminoscore method, based on precise acquisition conditions, requiring no calculations, and enabling tumor burden and treatment response to be monitored in mouse models.

Método Tumor Quantificação Baseada em bioluminescência para a progressão do tumor Monitoramento e efeitos do tratamento em modelos de ratos linfoma

Although bioluminescence imaging (BLI) shows promise for monitoring tumor burden in animal models of cancer, these analyses remain mostly qualitative. ...

Combined Near-infrared Fluorescent Imaging and Micro-computed Tomography for Directly Visualizing Cerebral Thromboemboli

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of stroke than relying on indirect measurements, and will be a potent and robust vascular research tool. We use an optical imaging approach that labels thrombi with a molecular imaging thrombus marker&#160;&#8212; a Cy5.5 near-infrared fluorescent (NIRF) probe that is covalently linked to the fibrin strands of the thrombus by the fibrin-crosslinking enzymatic action of activated coagulation factor XIIIa during the process of clot maturation. A micro-computed tomography (microCT)-based approach uses thrombus-seeking gold nanoparticles (AuNPs) functionalized to target the major component of the clot: fibrin. This paper describes a detailed protocol for the combined in vivo microCT and ex vivo NIRF imaging of thromboemboli in a mouse model of embolic stroke. We show that in vivo microCT and fibrin-targeted glycol-chitosan AuNPs (fib-GC-AuNPs) can be used for visualizing both in situ thrombi and cerebral embolic thrombi. We also describe the use of in vivo microCT-based direct thrombus imaging to serially monitor the therapeutic effects of tissue plasminogen activator-mediated thrombolysis. After the last imaging session, we demonstrate by ex vivo NIRF imaging the extent and the distribution of residual thromboemboli in the brain. Finally, we describe quantitative image analyses of microCT and NIRF imaging data. The combined technique of direct thrombus imaging allows two independent methods of thrombus visualization to be compared: the area of thrombus-related fluorescent signal on ex vivo NIRF imaging vs. the volume of hyperdense microCT thrombi in vivo.

This protocol describes the application of combined near-infrared fluorescent (NIRF) imaging and micro-computed tomography (microCT) for visualizing cerebral thromboemboli. This technique allows the quantification of thrombus burden and evolution. The NIRF imaging technique visualizes fluorescently labeled thrombus in excised brain, while the microCT technique visualizes thrombus inside living animals using gold-nanoparticles.

Combinada Near-infrared imagens fluorescentes e tomografia Micro-computado para Diretamente Visualizando Cerebral tromboêmbolos

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of ...

Determining Glucose Metabolism Kinetics Using 18F-FDG Micro-PET/CT

This paper describes the use of 18F-FDG and micro-PET/CT imaging to determine in vivo glucose metabolism kinetics in mice (and is transferable to rats). Impaired uptake and metabolism of glucose in multiple organ systems due to insulin resistance is a hallmark of type 2 diabetes. The ability of this technique to extract an image-derived input function from the vena cava using an iterative deconvolution method eliminates the requirement of the collection of arterial blood samples. Fitting of tissue and vena cava time activity curves to a two-tissue, three compartment model permits the estimation of kinetic micro-parameters related to the 18F-FDG uptake from the plasma to the intracellular space, the rate of transport from intracellular space to plasma and the rate of 18F-FDG phosphorylation. This methodology allows for multiple measures of glucose uptake and metabolism kinetics in the context of longitudinal studies and also provides insights into the efficacy of therapeutic interventions.

Determining Glucose Metabolism Kinetics Using 18F-FDG Micro-PET/CT

This study describes a protocol that uses 18F-FDG and positron emission tomography/computed tomography (PET/CT) imaging, together with kinetic modelling, to quantify the in vivo, real-time uptake of 18F-FDG into tissues.

Determinando Glucose Metabolismo Kinetics Usando<sup&gt; 18</sup&gt; F-FDG Micro-PET / CT

This paper describes the use of 18F-FDG and micro-PET/CT imaging to determine in vivo glucose metabolism kinetics in mice (and is transferable to rats). ...

Induction and Micro-CT Imaging of Cerebral Cavernous Malformations in Mouse Model

Mutations in the CCM1 (aka KRIT1), CCM2, or CCM3 (aka PDCD10) gene cause cerebral cavernous malformation (CCM) in humans. Mouse models of CCM disease have been established by tamoxifen induced deletion of Ccm genes in postnatal animals. These mouse models provide invaluable tools to investigate molecular mechanism and therapeutic approaches for CCM disease. An accurate and quantitative method to assess lesion burden and progression is essential to harness the full value of these animal models. Here, we demonstrate the induction of CCM disease in a mouse model and the use of the contrast enhanced X-ray micro computed tomography (micro-CT) method to measure CCM lesion burden in mouse brains. At postnatal day 1 (P1), we used 4-hydroxytamoxifen (4HT) to activate Cre recombinase activity from the Cdh5-CreErt2 transgene to cleave the floxed allele of Ccm2. CCM lesions in mouse brains were analyzed at P8. For micro-CT, iodine based Lugol&#39;s solution was used to enhance contrast in brain tissue. We have optimized the scan parameters and utilized a voxel dimension of 9.5 &#181;m, which lead to a minimum feature size of approximately 25 &#181;m. This resolution is sufficient to measure CCM lesion volume and number globally and accurately, and provide high-quality 3-D mapping of CCM lesions in mouse brains. This method enhances the value of the established mouse models to study the molecular basis and potential therapies for CCM and other cerebrovascular diseases.

This protocol demonstrates the induction of cerebral cavernous malformation disease in a mouse model and uses contrast enhanced micro computed tomography to measure lesion burden. This method enhances the value of established mouse models to study the molecular basis and potential therapies for cerebral cavernous malformation and other cerebrovascular diseases.

Indução e Micro-CT Imaging de malformações cavernosas cerebrais no modelo de Mouse

Mutations in the CCM1 (aka KRIT1), CCM2, or CCM3 (aka PDCD10) gene cause cerebral cavernous malformation (CCM) in humans. Mouse models of CCM disease have ...

Quantitative Micro-CT Analysis of Aortopathy in a Mouse Model of &#946;-aminopropionitrile-induced Aortic Aneurysm and Dissection

Aortic aneurysm and dissection is associated with significant morbidity and mortality in the population and can be highly lethal. While animal models of aortic disease exist, in vivo imaging of the vasculature has been limited. In recent years, micro-computerized tomography (micro-CT) has emerged as a preferred modality for imaging both large and small vessels both in vivo and ex vivo. In conjunction with a method of vascular casting, we have successfully used micro-CT to characterize the frequency and distribution of aortic pathology in &#946;-aminopropionitrile-treated C57/Bl6 mice. Technical limitations of this method include variations in the quality of the perfusion introduced by poor animal preparation, the application of proper methodologies for vessel size quantification, and the non-survivability of this procedure. This article details a methodology for the intravascular perfusion of a lead-based radiopaque silicone rubber for the quantitative characterization of aortopathy in a mouse model of aneurysm and dissection. In addition to visualizing aortic pathology, this method may be used for examining other vascular beds in vivo or vascular beds removed post-mortem.

Quantitative Micro-CT Analysis of Aortopathy in a Mouse Model of &amp;#946;-aminopropionitrile-induced Aortic Aneurysm and Dissection

This article describes a detailed methodology of using a radiopaque lead-based silicone rubber to perfuse the murine vasculature for aortic diameter quantification in a mouse model of aortic aneurysm and dissection.

Análise quantitativa de Micro-CT de Aortopathy em um modelo do rato de β-aminopropionitrile-induzida de aneurisma da aorta e dissecação

Aortic aneurysm and dissection is associated with significant morbidity and mortality in the population and can be highly lethal. While animal models of ...

Dual Bioluminescence Imaging of Tumor Progression and Angiogenesis

Angiogenesis, as a crucial process of tumor progression, has become a research hotspot and target of anti-tumor therapy. However, there is no reliable model for tracing tumor progression and angiogenesis simultaneously in a visual and sensitive manner. Bioluminescence imaging displays its unique superiority in living imaging due to its advantages of high sensitivity, strong specificity, and accurate measurement. Presented here is a protocol to establish a tumor-bearing mouse model by injecting a Renilla luciferase-labeled murine breast cancer cell line 4T1 into the transgenic mouse with angiogenesis-induced Firefly luciferase expression. This mouse model provides a valuable tool to simultaneously monitor tumor progression and angiogenesis in real-time by dual bioluminescence imaging in a single mouse. This model may be widely applied in anti-tumor drug screening and oncology research.

This protocol describes the establishment of a tumor-bearing mouse model to monitor tumor progression and angiogenesis in real-time by dual bioluminescence imaging.

Imagem de bioluminescência dupla de progressão tumoral e angiogênese

Angiogenesis, as a crucial process of tumor progression, has become a research hotspot and target of anti-tumor therapy. However, there is no reliable ...

Evaluation of Capnography Sampling Line Compatibility and Accuracy when Used with a Portable Capnography Monitor

Capnography is commonly used to monitor patient&#8217;s ventilatory status. While sidestream capnography has been shown to provide a reliable assessment of end-tidal CO2 (ETCO2), its accuracy is commonly validated using commercial kits composed of a capnography monitor and its matching disposable nasal cannula sampling lines. The purpose of this study was to assess the compatibility and accuracy of cross-paired capnography sampling lines with a single portable bedside capnography monitor. A series of 4 bench tests were performed to evaluate the tensile strength, rise time, ETCO2 accuracy as a function of respiratory rate, and ETCO2 accuracy in the presence of supplemental O2. Each bench test was performed using specialized, validated equipment to allow for a full evaluation of sampling line performance. The 4 bench tests successfully differentiated between sampling lines from different commercial sources and suggested that due to increased rise time and decreased ETCO2 accuracy, not all nasal cannula sampling lines provide reliable clinical data when cross-paired with a commercial capnography monitor. Care should be taken to ensure that any cross-pairing of capnography monitors and disposable sampling lines is fully validated for use across respiratory rates and supplemental O2 flow rates commonly encountered in clinical settings.

The goal of this study was to evaluate the accuracy of capnography sampling lines used in conjunction with a portable bedside capnography monitor. Sampling lines from 7 manufacturers were evaluated for tensile strength, rise time, and ETCO2 accuracy as a function of respiratory rate or supplemental oxygen flow rate.

Avaliação da compatibilidade e precisão da linha de amostragem da capnografia quando usado com um monitor de capnografia portátil

Capnography is commonly used to monitor patient&#8217;s ventilatory status. While sidestream capnography has been shown to provide a reliable assessment ...