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Todos os procedimentos que envolvem seres animais foram aprovados pelo Comitê Institucional Hospital Animal Care University. 1. Inoculação bacteriana intra-articular <ol><li> Antes da injecção, anestesiar coelhos através de uma injecção intramuscular de cetamina (30 mg / kg de peso corporal) misturado com xilazina (4 mg / kg) no músculo eretor espinhal. Certifique-se de animais são totalmente anestesiado, verificando que eles não conseguem responder a pitada pata. Este protocolo proporciona anestesia suficiente para a injecção intra-articular da articulação do joelho. Coloque os animais sob máscara de oxigênio durante a anestesia. </li><li> Raspar o joelho dos animais. Preparar o joelho por injecção asséptica por três toalhetes alternados de esfrega de povidona-iodo e álcool, seguido pela aplicação de uma solução de iodo-povidona. </li><li> Identificar manualmente o tendão patelar, uma estrutura elástica, na face anterior do joelho utilizando uma ponta de agulha estéril imediata ou uma sonda estéril. </li><li&gt; com controlo visual e usando uma abordagem anterior, o lugar de uma agulha 25 G por via percutânea no joelho direito de cada um dos 12 coelhos através do tendão patelar. </li><li> Injectar cada joelho com 1 ml de uma suspensão bacteriana de S. aureus (estirpe Neumann), a uma concentração de 10 6 UFC / ml. Uma injecção sem resistência confirma o local intra-articular da ponta da agulha. </li><li> Após os procedimentos de injeção, manter o animal sob fonte de convecção, para evitar a perda de calor e monitorar a frequência respiratória, observando o movimento do tórax. Uma vez acordado, manter os animais em gaiolas com livre acesso a água e comida. </li><li> Controlar a dor através da administração de uma injeção intramuscular de 0,1 mg / kg de buprenorfina a cada 8 horas. </li><li> Clinicamente observar coelhos cada dia, o controlo quantidades consumidas de água e comida, perda de peso, a temperatura, e o comportamento geral. </li><li> Para a imagem da fase aguda da infecção realizar a primeira sessão de imagens MR, logocomo um animal apresenta uma perda de peso significativa (10%), em geral isto ocorre após cerca de 2 dias. </li><li> Se for necessária a administração de drogas intravenosas antes do exame de ressonância magnética, um acesso venoso auricular pode ser instalado (cf. abaixo). </li></ol> 2. Exame de ressonância magnética Quando os animais vivem de imagem, a instalação de animais cuidado é uma característica fundamental para garantir o conforto dos animais e anestesia ideal. Isto permitirá obter os melhores resultados de imagem e assegurar a aquisição de uma imagem de reprodução para os estudos longitudinais. Devido ao tamanho do animal, a utilização de uma unidade MR clínico de tamanho (1,5 T ou T 3) é o mais adequado. 8 canais bobina clínica do joelho é usada como ela fornece resolução adequada e taxa de contraste-ruído para exploração do joelho de coelho. <ol><li> Antes da instalação do sistema de imagem, instale um acesso venoso periférico através de uma veia auricular. Este acesso vai servir para injectar o agente de contraste. <ol><li> Raspar e desinfectar a orelha. </li><li&gt; Realizar a anestesia local por injecção subcutânea de lidocaína. </li><li> Inserir um cateter de 25 G no interior da veia auricular lateral. </li><li> Avaliar a permeabilidade pela injeção de 1 ml de soro fisiológico estéril. </li><li> Manter o cateter com tapping adesiva. </li></ol></li><li> Anestesiar animais por meio de injecção intramuscular de cetamina (30 mg / kg de peso corporal) misturado com xilazina (4 mg / kg). Os animais são totalmente anestesiado, uma vez que não respondem ao aperto da pata. Coloque uma máscara facial, no coelho, dando-lhe oxigénio com uma taxa de fluxo de 200 ml / min. </li><li> Depois de completamente anestesiado, levar os animais para a unidade de ressonância magnética. Colocar animais de modo que os joelhos estão localizadas no centro da bobina de MR. Coloque as pernas dos animais em extensão completa, de modo que o eixo longitudinal da tíbia é paralela à mesa unidade de imagens MR. Use velcro ou sacos de areia para manter a posição da perna ideal. </li><li> Monitorização cardio-respiratória dos animais não é necessário que oprotocolo de anestesia permite anestesia profunda em respiração espontânea, mas os animais têm que ser cobertos para evitar a perda de calor anestesia induzida. </li><li> Protocolo de MR está detalhado na Tabela 1. O tempo médio para a aquisição total, incluindo instalação ideal é de cerca de 20 min. </li><li> Realizar ressonância magnética em diferentes planos. No entanto, o plano transversal dos joelhos (ortogonal à tíbia) é o plano de referência, uma vez que assegura a reprodutibilidade anatómica da posição da imagem para exames longitudinais sequenciais e permite a correlação óptima com fatias histológicas. </li><li> Ao término das seqüências não melhorada, injetar o agente de contraste UPSIO através do acesso venoso auricular. Lentamente administrar as partículas de óxido de ferro em uma dose única de 150 mol de Fe / kg. Lavar o cateter por injecção de 1 ml de soro fisiológico estéril. </li><li> Repetir a sequência reforçada GRE ponderada 24 horas após a injecção. Este atraso permite que as partículas a serem fagocitadas pelosos macrófagos. </li><li> Para os estudos longitudinais avaliando efeito de drogas (antibióticos, esteróides, anticorpos anti-macrófago, etc.), Repetir os exames de RM seqüenciais usando o protocolo acima descrito. </li></ol> 3. Análise de Imagem <ol><li> Para a avaliação longitudinal realizar medições no mesmo nível anatômico, e definir um marco facilmente identificáveis. Por exemplo, a aquisição através do plano axial que o maior diâmetro da patela é observada é uma forma fiável para se obter a medição reprodutível (Figura 1). </li><li> Realizar análise de imagem usando um software baseado em DICOM (como Osirix) ou um software de processamento de imagem (ImageJ). </li><li> Usando o software ImageJ, realizar a segmentação da área sinovial que demonstra a perda de sinal de imagem ponderada em T2 USPIO-enhanced GRE usar a &quot;área irregular&quot; ferramenta de desenho em. Uma vez que a membrana sinovial com sinal escuro é descrito, clique em &quot;Analisar&quot; para obter a área /número de pixels (Figura 2). </li></ol>

<ol>
	<li>Madri, J., Kissane, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inflammation+and+healing.">Inflammation and healing.</a> Anderson's Pathology. , 67-110 (1990).</li><li>Sephel, G., Woodward, S., Rubin, R., Strayer, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Repair,+regeneration,+and+fibrosis.">Repair, regeneration, and fibrosis.</a> Rubin's Pathology. , 71-98 (2008).</li><li>Verdrengh, M., Tarkowski, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+macrophages+in+Staphylococcus+aureus-induced+arthritis+and+sepsis.">Role of macrophages in Staphylococcus aureus-induced arthritis and sepsis.</a> Arthritis Rheum. 43 (10), 2276-2282 (2000).</li><li>Heale, J., Speert, D., Burke, B., Lewis, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophages+in+bacterial+infection.">Macrophages in bacterial infection.</a> The Macrophage. , 210-252 (2008).</li><li>Bierry, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophage+activity+in+infected+areas+of+an+experimental+vertebral+osteomyelitis+model:+USPIO-enhanced+MR+imaging--feasibility+study.">Macrophage activity in infected areas of an experimental vertebral osteomyelitis model: USPIO-enhanced MR imaging--feasibility study.</a> Radiology. 248 (1), 114-123 (2008).</li><li>Bierry, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MRI+of+macrophages+in+infectious+knee+synovitis.">MRI of macrophages in infectious knee synovitis.</a> AJR Am. J. Roentgenol. 194 (6), W521-W526 (2010).</li><li>Lutz, A. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+of+synovial+macrophages+in+an+experimental+rabbit+model+of+antigen-induced+arthritis:+ultrasmall+superparamagnetic+iron+oxide-enhanced+MR+imaging.">Detection of synovial macrophages in an experimental rabbit model of antigen-induced arthritis: ultrasmall superparamagnetic iron oxide-enhanced MR imaging.</a> Radiology. 233 (1), 149-1457 (2004).</li><li>Weissleder, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrasmall+superparamagnetic+iron+oxide:+an+intravenous+contrast+agent+for+assessing+lymph+nodes+with+MR+imaging.">Ultrasmall superparamagnetic iron oxide: an intravenous contrast agent for assessing lymph nodes with MR imaging.</a> Radiology. 175 (2), 494-498 (1990).</li><li>Lefevre, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Septic+arthritis:+monitoring+with+USPIO-enhanced+macrophage+MR+imaging.">Septic arthritis: monitoring with USPIO-enhanced macrophage MR imaging.</a> Radiology. 258 (3), 722-728 (2011).</li><li>Sigovan, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid-clearance+iron+nanoparticles+for+inflammation+imaging+of+atherosclerotic+plaque:+initial+experience+in+animal+model.">Rapid-clearance iron nanoparticles for inflammation imaging of atherosclerotic plaque: initial experience in animal model.</a> Radiology. 252 (2), 401-409 (2009).</li></ol>

Os autores não têm nada a revelar.

Enquanto agentes de contraste à base de gadolínio inespecíficos fornecer informações sobre o volume ea perfusão do espaço extracelular, macrófagos imagem por USPIO-enhanced MR permite a localização anatômica precisa e uma avaliação qualitativa da infiltração de macrófagos no synovium infectado, sem a necessidade de amostras de tecido 9. Devido à sua alta sensibilidade, USPIO pode demonstrar se infiltrar até mesmo sutil celular presente nas fases iniciais da infecção. Sob terapia antibióti...

A ressonância magnética (MRI) é considerada a modalidade de escolha para a demonstração da sinovite infecciosa, devido à sua alta resolução espacial e de contraste de tecido mole. As alterações dos sinais observados na ressonância magnética na artrite baixo sinal T1 e T2 alta refletindo o aumento da presença de teor de água extracelular, e uma melhoria acentuada após a administração do agente baseado em gadolínio, de acordo com os resultados de histologicamente aumento da vascularização devido a vasodilatação ea angiogênese 1. No entanto, é muitas vezes incapaz de MRI para demonstrar a resolução da infecção durante a terapia com antibióticos como reforço persistente pode ser observada nas articulações de pacientes com doença sistémica e artrite séptica biologicamente curado devido à persistência do espaço extracelular alargado (tecido de granulação, cicatriz fibrótica) 2. Além das alterações extracelulares, as células inflamatórias, incluindo o recrutamento de uma intensa infiltração de macrófagos na massivamente atadas sinóvia. Os macrófagos desempenham um papel importante, tanto para a fase aguda e crónica da infecção bacteriana 3. Eles induzir a reacção inflamatória necessária para erradicar microorganismos patogénicos, e coordenar resolução da inflamação, tal como a inflamação induzida por macrófago persiste enquanto tecidos necróticos não são removidos, evitando reparação para começar 4. Assim, a redução de infiltração de macrófagos na sinóvia infectado após a terapia eficiente pode ser um indicador fiável da resolução da infecção. Celular de imagem é capaz de demonstrar a infiltração celular específica dentro do tecido patológico. Específica de macrófagos RM usando direcionados agente de contraste tem sido amplamente investigado e demonstrou a sua capacidade para demonstrar inflamação ou infecção 5-7 conjunta. Depois de injecção intravenosa, tais agentes de contraste específicos, tais como (USPIO ultrasmall óxidos de ferro superparamagnéticos) partículas são tomadas por células fagocíticas, tais como macrófagos e,devido às suas propriedades magnéticas, induzem alterações de sinal nos tecidos que apresentam infiltração de macrófagos 8. O acompanhamento longitudinal dos MR sinal de mudanças terapia permite uma avaliação não invasiva em vivo de infiltração de macrófagos, e uma redução de USPIO carregados-macrófagos mudanças de sinal relacionados demonstraria o sucesso da terapia. O objetivo deste relatório é apresentar como realizar macrófagos ressonância magnética para monitorar de forma não invasiva a artrite séptica, demonstrando a redução da infiltração de macrófagos dentro da sinóvia.

<table border="1">
	<tbody>
		<tr>
			<td>Name of Reagent/Material</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>P904</td>
			<td>Guerbet</td>
			<td></td>
			<td>Dose: 150 &#956;mol Fe/kg</td>
		</tr>
		<tr>
			<td>Ketamine (500 mg/ml ketamine)</td>
			<td>Virbac</td>
			<td></td>
			<td>Dose: 30 mg/kg</td>
		</tr>
		<tr>
			<td>Rompun (20 mg/ml Xylazine)</td>
			<td>Axience</td>
			<td></td>
			<td>Dose: 4 mg/kg</td>
		</tr>
		<tr>
			<td>Buprenorphine</td>
			<td>Vetoquinol</td>
			<td></td>
			<td>Dose: 0.1 mg/kg/8 hr</td>
		</tr>
		<tr>
			<td>BD 22 G, 1 inch</td>
			<td>BD Biosciences</td>
			<td>381423</td>
			<td></td>
		</tr>
		<tr>
			<td>BD 25 G, 5/8 inch</td>
			<td>BD Biosciences</td>
			<td>305122</td>
			<td></td>
		</tr>
	</tbody>
</table>

in vivo macrophage imaging using mr targeted contrast agent for longitudinal evaluation of septic arthritis

Os macrófagos são células-chave na iniciação, o desenvolvimento e a regulação da resposta inflamatória a uma infecção bacteriana. Os macrófagos são intensivamente e cada vez mais recrutados nas articulações sépticos desde as primeiras fases da infecção e a infiltração é suposto a regredir vez remoção eficiente dos patógenos é obtido. A capacidade de identificar em atividade dos macrófagos in vivo em uma articulação infectada pode, portanto, fornecer duas aplicações principais: a detecção precoce de sinovite aguda e monitorização da terapêutica. In vivo, a detecção não invasiva de macrófagos pode ser realizada por meio da ressonância magnética, utilizando nanopartículas de ferro, tais como óxido de ferro superparamagnético ultrasmall (USPIO). Após administração intravenosa ou intra-articular, USPIO são especificamente fagocitadas por macrófagos ativados e, devido às suas propriedades magnéticas, induzir mudanças de sinal em tecidos que apresentam infiltração de macrófagos. A quantitative avaliação do infiltrado é viável, já que a área com a perda de sinal (número de pixels escuros) observado em imagens de eco de gradiente MR após a injecção de partículas está correlacionado com a quantidade de ferro no tecido e, portanto, reflecte o número de células de USPIO-carregados. Apresentamos aqui um protocolo para realizar imagem macrófagos usando USPIO avançada ressonância magnética em um modelo animal de artrite séptica, permitindo uma inicial e longitudinal na avaliação não invasiva vivo infiltração de macrófagos e uma avaliação das medidas de terapia.

Nas imagens não melhorada, a membrana sinovial de joelhos infectados apresenta um inchaço difuso sinal intermediário que não é distinguível de tecido mole circundante, enquanto fémur e da patela aparecer como estruturas de sinal baixo (Figura 1). Nas imagens USPIO avançada, 24 horas após a administração do agente de contraste, que contém a área sinovial macrófagos USPIO-loaded irá demonstrar a perda de sinal (Figuras 1 e 2). <...

Watch this Scientific Journal Video about In vivo Macrophage Imaging Using MR Targeted Contrast Agent for Longitudinal Evaluation of Septic Arthritis at JoVE.com

In vivo Macrophage Imaging Using MR Targeted Contrast Agent for Longitudinal Evaluation of Septic Arthritis

Nós demonstramos como realizar macrófagos RM usando ultrasmall agente de contraste superparamagnético (USPIO) na artrite séptica, permitindo uma inicial e longitudinal<em&gt; In vivo</em&gt; Avaliação não-invasiva da infiltração de macrófagos e uma avaliação da eficácia terapêutica.

In vivo macrófagos Imagem Usando MR alvejado agente de contraste para avaliação longitudinal de artrite séptica

Macrophages are key-cells in the initiation, the development and the regulation of the inflammatory response to bacterial infection. Macrophages are ...

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Research

JoVE Journal

Medicine

In vivo Macrophage Imaging Using MR Targeted Contrast Agent for Longitudinal Evaluation of Septic Arthritis

9.3K visualizações.  University Hospital of Strasbourg. Nós demonstramos como realizar macrófagos RM usando ultrasmall agente de contraste superparamagnético (USPIO) na artrite séptica, permitindo uma inicial e longitudinal In vivo Avaliação não-invasiva da infiltração de macrófagos e uma avaliação da eficácia terapêutica.

Vídeo: In vivo Macrophage Imaging Using MR Targeted Contrast Agent for Longitudinal Evaluation of Septic Arthritis

Contrast Enhanced Vessel Imaging using MicroCT

Microscopic computed tomography (microCT) offers high-resolution volumetric imaging of the anatomy of living small animals. However, the contrast between different soft tissues and body fluids is inherently poor in micro-CT images 1. Under these circumstances, visualization of blood vessels becomes a nearly impossible task. To overcome this and to improve the visualization of blood vessels exogenous contrast agents can be used. Herein, we present a methodology for visualizing the vascular network in a rodent model. By using a long-acting aqueous colloidal polydisperse iodinated blood-pool contrast agent, eXIA 160XL, we optimized image acquisition parameters and volume-rendering techniques for finding blood vessels in live animals. Our findings suggest that, to achieve a superior contrast between bone and soft tissue from vessel, multiple-frames (at least 5-8/ frames per view), and 360-720 views (for a full 360&deg; rotation) acquisitions were mandatory. We have also demonstrated the use of a two-dimensional transfer function (where voxel color and opacity was assigned in proportion to CT value and gradient magnitude), in visualizing the anatomy and highlighting the structure of interest, the blood vessel network. This promising work lays a foundation for the qualitative and quantitative assessment of anti-angiogenesis preclinical studies using transgenic or xenograft tumor-bearing mice.

Contrast enhanced small animal vessel imaging by microCT is a rapid, cost-effective and high-throughput technique for serial in situ examination for tumor development, for analyzing the network of blood vessels that nourish them, and for following the response of tumors to preclinical therapeutic intervention(s).

Contraste de imagem aprimorada navio usando MicroCT

Microscopic computed tomography (microCT) offers high-resolution volumetric imaging of the anatomy of living small animals. However, the contrast between ...

Medicina

Evaluation of Nanoparticle Uptake in Tumors in Real Time Using Intravital Imaging

Current technologies for tumor imaging, such as ultrasound, MRI, PET and CT, are unable to yield high-resolution images for the assessment of nanoparticle uptake in tumors at the microscopic level1,2,3, highlighting the utility of a suitable xenograft model in which to perform detailed uptake analyses. Here, we use high-resolution intravital imaging to evaluate nanoparticle uptake in human tumor xenografts in a modified, shell-less chicken embryo model. The chicken embryo model is particularly well-suited for these in vivo analyses because it supports the growth of human tumors, is relatively inexpensive and does not require anesthetization or surgery 4,5. Tumor cells form fully vascularized xenografts within 7 days when implanted into the chorioallantoic membrane (CAM) 6. The resulting tumors are visualized by non-invasive real-time, high-resolution imaging that can be maintained for up to 72 hours with little impact on either the host or tumor systems. Nanoparticles with a wide range of sizes and formulations administered distal to the tumor can be visualized and quantified as they flow through the bloodstream, extravasate from leaky tumor vasculature, and accumulate at the tumor site. We describe here the analysis of nanoparticles derived from Cowpea mosaic virus (CPMV) decorated with near-infrared fluorescent dyes and/or polyethylene glycol polymers (PEG) 7, 8, 9,10,11. Upon intravenous administration, these viral nanoparticles are rapidly internalized by endothelial cells, resulting in global labeling of the vasculature both outside and within the tumor7,12. PEGylation of the viral nanoparticles increases their plasma half-life, extends their time in the circulation, and ultimately enhances their accumulation in tumors via the enhanced permeability and retention (EPR) effect 7, 10,11. The rate and extent of accumulation of nanoparticles in a tumor is measured over time using image analysis software. This technique provides a method to both visualize and quantify nanoparticle dynamics in human tumors.

We present a novel approach to quantify nanoparticle localization in the vasculature of human xenografted tumors using dynamic, real-time intravital imaging in an avian embryo model.

Avaliação de Captação de nanopartículas em tumores em tempo real usando imagens intravital

Current technologies for tumor imaging, such as ultrasound, MRI, PET and CT, are unable to yield high-resolution images for the assessment of nanoparticle ...

Longitudinal Evaluation of Mouse Hind Limb Bone Loss After Spinal Cord Injury using Novel, in vivo, Methodology

Spinal cord injury (SCI) is often accompanied by osteoporosis in the sublesional regions of the pelvis and lower extremities, leading to a higher frequency of fractures 1. As these fractures often occur in regions that have lost normal sensory function, the patient is at a greater risk of fracture-dependent pathologies, including death. SCI-dependent loss in both bone mineral density (BMD, grams/cm2) and bone mineral content (BMC, grams) has been attributed to mechanical disuse 2, aberrant neuronal signaling 3 and hormonal changes 4. The use of rodent models of SCI-induced osteoporosis can provide invaluable information regarding the mechanisms underlying the development of osteoporosis following SCI as well as a test environment for the generation of new therapies 5-7 (and reviewed in 8). Mouse models of SCI are of great interest as they permit a reductionist approach to mechanism-based assessment through the use of null and transgenic mice. While such models have provided important data, there is still a need for minimally-invasive, reliable, reproducible, and quantifiable methods in determining the extent of bone loss following SCI, particularly over time and within the same cohort of experimental animals, to improve diagnosis, treatment methods, and/or prevention of SCI-induced osteoporosis.
An ideal method for measuring bone density in rodents would allow multiple, sequential (over time) exposures to low-levels of X-ray radiation. This study describes the use of a new whole-animal scanner, the IVIS Lumina XR (Caliper Instruments) that can be used to provide low-energy (1-3 milligray (mGy)) high-resolution, high-magnification X-ray images of mouse hind limb bones over time following SCI. Significant bone density loss was seen in the tibiae of mice by 10 days post-spinal transection when compared to uninjured, age-matched control (na&iuml;ve) mice (13% decrease, p&lt;0.0005). Loss of bone density in the distal femur was also detectable by day 10 post-SCI, while a loss of density in the proximal femur was not detectable until 40 days post injury (7% decrease, p&lt;0.05). SCI-dependent loss of mouse femur density was confirmed post-mortem through the use of Dual-energy X-ray Absorptiometry (DXA), the current "gold standard" for bone density measurements. We detect a 12% loss of BMC in the femurs of mice at 40 days post-SCI using the IVIS Lumina XR. This compares favorably with a previously reported BMC loss of 13.5% by Picard and colleagues who used DXA analysis on mouse femurs post-mortem 30 days post-SCI 9. Our results suggest that the IVIS Lumina XR provides a novel, high-resolution/high-magnification method for performing long-term, longitudinal measurements of hind limb bone density in the mouse following SCI.

Longitudinal Evaluation of Mouse Hind Limb Bone Loss After Spinal Cord Injury using Novel, in vivo, Methodology

A longitudinal examination of bone loss in the femurs and tibiae of adult mice was performed following spinal cord injury using sequential low-dose X-ray scans. Tibia bone loss was detected throughout the study, while bone loss in the femur was not detected until 40 days post injury.

Avaliação longitudinal do rato Perda Hind Limb óssea após lesão medular usando Novel, In vivo Metodologia,

Spinal cord injury (SCI) is often accompanied by osteoporosis in the sublesional regions of the pelvis and lower extremities, leading to a higher ...

Transplantation into the Anterior Chamber of the Eye for Longitudinal, Non-invasive In vivo Imaging with Single-cell Resolution in Real-time

Intravital imaging has emerged as an indispensable tool in biological research. In the process, many imaging techniques have been developed to study different biological processes in animals non-invasively. However, a major technical limitation in existing intravital imaging modalities is the inability to combine non-invasive, longitudinal imaging with single-cell resolution capabilities. We show here how transplantation into the anterior chamber of the eye circumvents such significant limitation offering a versatile experimental platform that enables non-invasive, longitudinal imaging with cellular resolution in vivo. We demonstrate the transplantation procedure in the mouse and provide representative results using a model with clinical relevance, namely pancreatic islet transplantation. In addition to enabling direct visualization in a variety of tissues transplanted into the anterior chamber of the eye, this approach provides a platform to screen drugs by performing long-term follow up and monitoring in target tissues. Because of its versatility, tissue/cell transplantation into the anterior chamber of the eye not only benefits transplantation therapies, it extends to other in vivo applications to study physiological and pathophysiological processes such as signal transduction and cancer or autoimmune disease development.

Transplantation into the Anterior Chamber of the Eye for Longitudinal, Non-invasive In vivo Imaging with Single-cell Resolution in Real-time

A new approach combining intraocular transplantation and confocal microscopy enables longitudinal, non-invasive real-time imaging with single-cell resolution within grafted tissues in vivo. We demonstrate how to transplant pancreatic islets into the anterior chamber of the mouse eye.

Transplante para a câmara anterior do olho para longitudinal, não-invasivo<em&gt; Em vivo</em&gt; Imaging com uma única célula de resolução em tempo real

Intravital imaging has emerged as an indispensable tool in biological research.  In the process, many imaging techniques have been developed to study ...

MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent

Tumor extracellular matrix has abundance of cancer related proteins that can be used as biomarkers for cancer molecular imaging. In this work, we demonstrated effective MR cancer molecular imaging with a small molecular peptide targeted Gd-DOTA monoamide complex as a targeted MRI contrast agent specific to clotted plasma proteins in tumor stroma. We performed the experiment of evaluating the effectiveness of the agent for non-invasive detection of prostate tumor with MRI in a mouse orthotopic PC-3 prostate cancer model. The targeted contrast agent was effective to produce significant tumor contrast enhancement at a low dose of 0.03 mmol Gd/kg. The peptide targeted MRI contrast agent is promising for MR molecular imaging of prostate tumor.

To demonstrate MR cancer molecular imaging with a small peptide targeted MRI contrast agent specific to clotted plasma proteins in tumor stroma in a mouse prostate cancer model.

MR Imagem Molecular do cancro da próstata com um pequeno Molecular CLT1 Peptide alvejado agente de contraste

Tumor extracellular  matrix has abundance of cancer related proteins that can be used as biomarkers  for cancer molecular imaging. In this work,  we ...

In Vivo Optical Imaging of Brain Tumors and Arthritis Using Fluorescent SapC-DOPS Nanovesicles

We describe a multi-angle rotational optical imaging (MAROI) system for in vivo monitoring of physiopathological processes labeled with a fluorescent marker. Mouse models (brain tumor and arthritis) were used to evaluate the usefulness of this method. Saposin C (SapC)-dioleoylphosphatidylserine (DOPS) nanovesicles tagged with CellVue Maroon (CVM) fluorophore were administered intravenously. Animals were then placed in the rotational holder (MARS) of the in vivo imaging system. Images were acquired in 10&#176; steps over 380&#176;. A rectangular&#160;region of interest (ROI) was placed across the full image width at the model disease site. Within the ROI, and for every image, mean fluorescence intensity was computed after background subtraction. In the mouse models studied, the labeled nanovesicles were taken up in both the orthotopic and transgenic brain tumors, and in the arthritic sites (toes and ankles). Curve analysis of the multi angle image ROIs determined the angle with the highest signal. Thus, the optimal angle for imaging each disease site was characterized. The MAROI method applied to imaging of fluorescent compounds is a noninvasive, economical, and precise tool for in vivo quantitative analysis of the disease states in the described mouse models.

In Vivo Optical Imaging of Brain Tumors and Arthritis Using Fluorescent SapC-DOPS Nanovesicles

We describe a multi-angle rotational optical imaging (MAROI) system for in vivo quantitation of a fluorescent marker delivered by saposin C (SapC)-dioleoylphosphatidylserine (DOPS) nanovesicles. Employing mouse models of cancer and arthritis, we demonstrate how the MAROI signal curve analysis can be used for the precise mapping and biological characterization of disease processes.

In Vivo Imagem Óptico de tumores cerebrais e artrite Usando fluorescente SAPC-DOPS nanovesículas

We describe a multi-angle rotational optical imaging (MAROI) system for in vivo monitoring of physiopathological processes labeled with a fluorescent ...

Longitudinal In Vivo Imaging of the Cerebrovasculature: Relevance to CNS Diseases

Remodeling of the brain vasculature is a common trait of brain pathologies. In vivo imaging techniques are fundamental to detect cerebrovascular plasticity or damage occurring overtime and in relation to neuronal activity or blood flow. In vivo two-photon microscopy allows the study of the structural and functional plasticity of large cellular units in the living brain. In particular, the thinned-skull window preparation allows the visualization of cortical regions of interest (ROI) without inducing significant brain inflammation. Repetitive imaging sessions of cortical ROI are feasible, providing the characterization of disease hallmarks over time during the progression of numerous CNS diseases. This technique accessing the pial structures within 250 &#956;m of the brain relies on the detection of fluorescent probes encoded by genetic cellular markers and/or vital dyes. The latter (e.g., fluorescent dextrans) are used to map the luminal compartment of cerebrovascular structures. Germane to the protocol described herein is the use of an in vivo marker of amyloid deposits, Methoxy-O4, to assess Alzheimer&#39;s disease (AD) progression. We also describe the post-acquisition image processing used to track vascular changes and amyloid depositions. While focusing presently on a model of AD, the described protocol is relevant to other CNS disorders where pathological cerebrovascular changes occur.

Longitudinal In Vivo Imaging of the Cerebrovasculature: Relevance to CNS Diseases

This manuscript describes a procedure to track the remodeling of the cerebrovasculature during amyloid plaque accumulation in vivo using longitudinal two-photon microscopy. A thinned-skull preparation enables the visualization of fluorescent dyes to assess the progression of cerebrovascular damage in a mouse model of Alzheimer&#39;s disease.

Longitudinal<em&gt; In Vivo</em&gt; Imagens do Cerebrovasculature: Relevância para doenças do SNC

Remodeling of the brain vasculature is a common trait of brain pathologies. In vivo imaging techniques are fundamental to detect cerebrovascular ...

Phase Contrast Magnetic Resonance Imaging in the Rat Common Carotid Artery

Phase contrast magnetic resonance imaging (PC-MRI) is a noninvasive approach that can quantify flow-related parameters such as blood flow. Previous studies have shown that abnormal blood flow may be associated with systemic vascular risk. Thus, PC-MRI can facilitate the translation of data obtained from animal models of cardiovascular diseases to pertinent clinical investigations. In this report, we describe the procedure for measuring blood flow in the common carotid artery (CCA) of rats using cine-gated PC-MRI and discuss relevant analysis methods. This procedure can be performed in a live, anesthetized animal and does not require euthanasia after the procedure. The proposed scanning parameters yield repeatable measurements for blood flow, indicating excellent reproducibility of the results. The PC-MRI procedure described in this article can be used for pharmacological testing, pathophysiological assessment, and cerebral hemodynamics evaluation.

The overall goal of this procedure is to measure the blood flow in the rat common carotid artery by using noninvasive phase contrast magnetic resonance imaging.

Imagens de ressonância magnética fase contraste na artéria carótida comum de rato

Phase contrast magnetic resonance imaging (PC-MRI) is a noninvasive approach that can quantify flow-related parameters such as blood flow. Previous ...

Quantitative [18F]-Naf-PET-MRI Analysis for the Evaluation of Dynamic Bone Turnover in a Patient with Facetogenic Low Back Pain

Imaging techniques that reflect dynamic bone turnover may aid in characterizing a wide range of bone pathologies. Bone is a dynamic tissue undergoing continuous remodeling with the competing activity of osteoblasts, which produce the new bone matrix, and osteoclasts, whose function is to eliminate mineralized bone. [18F]-NaF is a positron emission tomography (PET) radiotracer that enables visualization of bone metabolism. [18F]-NaF is chemically absorbed into hydroxyapatite in the bone matrix by osteoblasts and can thus noninvasively detect osteoblastic activity, which is occult to conventional imaging techniques. Kinetic modeling of dynamic [18F]-NaF-PET data provides detailed quantitative measures of bone metabolism. Conventional semi-quantitative PET data, which utilizes standardized uptake values (SUVs) as a measure of radiotracer activity, is referred to as a static technique due to its snapshot of tracer uptake in time.&#160; Kinetic modeling, however, utilizes dynamic image data where tracer levels are continuously acquired providing tracer uptake temporal resolution. From the kinetic modeling of dynamic data, quantitative values like blood flow and metabolic rate (i.e., potentially informative metrics of tracer dynamics) can be extracted, all with respect to the measured activity in the image data. When combined with dual modality PET-MRI, region-specific kinetic data can be correlated with anatomically registered high-resolution structural and pathologic information afforded by MRI. The goal of this methodological manuscript is to outline detailed techniques for performing and analyzing dynamic [18F]-NaF-PET-MRI data. The lumbar facet joint is a common site of degenerative arthritis disease and a common cause for axial low back pain.&#160; Recent studies suggest [18F]-NaF-PET may serve as a useful biomarker of painful facetogenic disease.&#160; The human lumbar facet joint will, therefore, be used as a prototypical region of interest for dynamic [18F]-NaF-PET-MRI analysis in this manuscript.

Quantitative [18F]-Naf-PET-MRI Analysis for the Evaluation of Dynamic Bone Turnover in a Patient with Facetogenic Low Back Pain

Imaging techniques that reflect dynamic bone turnover may aid in characterizing a wide range of bone pathologies. We present detailed methodologies for performing and analyzing dynamic [18F]-NaF-PET-MRI data in a patient with facetogenic low back pain using the lumbar facet joints as a prototypical region of interest.

Análise quantitativa [18F]-NAF-PET-RM para avaliação da rotatividade óssea dinâmica em paciente com dor nas costas Facetogênica

Imaging techniques that reflect dynamic bone turnover may aid in characterizing a wide range of bone pathologies. Bone is a dynamic tissue undergoing ...

Quantitative Mapping of Specific Ventilation in the Human Lung using Proton Magnetic Resonance Imaging and Oxygen as a Contrast Agent

Specific ventilation imaging (SVI) is a functional magnetic resonance imaging technique capable of quantifying specific ventilation &#8213; the ratio of the fresh gas entering a lung region divided by the region&#8217;s end-expiratory volume &#8213; in the human lung, using only inhaled oxygen as a contrast agent. Regional quantification of specific ventilation has the potential to help identify areas of pathologic lung function. Oxygen in solution in tissue shortens the tissue&#8217;s longitudinal relaxation time (T1), and thus a change in tissue oxygenation can be detected as a change in T1-weighted signal with an inversion recovery acquired image. Following an abrupt change between two concentrations of inspired oxygen, the rate at which lung tissue within a voxel equilibrates to a new steady-state reflects the rate at which resident gas is being replaced by inhaled gas. This rate is determined by specific ventilation. To elicit this sudden change in oxygenation, subjects alternately breathe 20-breath blocks of air (21% oxygen) and 100% oxygen while in the MRI scanner. A stepwise change in inspired oxygen fraction is achieved through use of a custom three-dimensional (3D)-printed flow bypass system with a manual switch during a short end-expiratory breath hold. To detect the corresponding change in T1, a global inversion pulse followed by a single shot fast spin echo sequence was used to acquire two-dimensional T1-weighted images in a 1.5&#160;T MRI scanner, using an eight-element torso coil. Both single slice and multi-slice imaging are possible, with slightly different imaging parameters. Quantification of specific ventilation is achieved by correlating the time-course of signal intensity for each lung voxel with a library of simulated responses to the air/oxygen stimulus. SVI estimations of specific ventilation heterogeneity have been validated against multiple breath washout and proved to accurately determine the heterogeneity of the specific ventilation distribution.

Specific ventilation imaging is a functional magnetic resonance imaging technique that allows for quantification of regional specific ventilation in the human lung, using inhaled oxygen as a contrast agent. Here, we present a protocol to collect and analyze specific ventilation imaging data.

Mapeamento quantitativo de ventilação específica no pulmão humano usando ressonância magnética de prótons e oxigênio como agente de contraste

Specific ventilation imaging (SVI) is a functional magnetic resonance imaging technique capable of quantifying specific ventilation &#8213; the ratio of ...