Micro-CT Based Experimental Liver Imaging Using a Nanoparticulate Contrast Agent: A Longitudinal Study in Mice

BACKGROUND: Micro-CT imaging of liver disease in mice relies on high soft tissue contrast to detect small lesions like liver metastases. Purpose of this study was to characterize the localization and time course of contrast enhancement of a nanoparticular alkaline earth metal-based contrast agent (VISCOVER ExiTron nano) developed for small animal liver CT imaging. METHODOLOGY: ExiTron nano 6000 and ExiTron nano 12000, formulated for liver/spleen imaging and angiography, respectively, were intravenously injected in C57BL/6J-mice. The distribution and time course of contrast enhancement were analysed by repeated micro-CT up to 6 months. Finally, mice developing liver metastases after intrasplenic injection of colon carcinoma cells underwent longitudinal micro-CT imaging after a single injection of ExiTron nano. PRINCIPAL FINDINGS: After a single injection of ExiTron nano the contrast of liver and spleen peaked after 4-8 hours, lasted up to several months and was tolerated well by all mice. In addition, strong contrast enhancement of abdominal and mediastinal lymph nodes and the adrenal glands was observed. Within the first two hours after injection, particularly ExiTron nano 12000 provided pronounced contrast for imaging of vascular structures. ExiTron nano facilitated detection of liver metastases and provided sufficient contrast for longitudinal observation of tumor development over weeks. CONCLUSIONS: The nanoparticulate contrast agents ExiTron nano 6000 and 12000 provide strong contrast of the liver, spleen, lymph nodes and adrenal glands up to weeks, hereby allowing longitudinal monitoring of pathological processes of these organs in small animals, with ExiTron nano 12000 being particularly optimized for angiography due to its very high initial vessel contrast

Three-Dimensional In Vivo Imaging of the Murine Liver: A Micro-Computed Tomography-Based Anatomical Study

Various murine models are currently used to study acute and chronic pathological processes of the liver, and the efficacy of novel therapeutic regimens. The increasing availability of high-resolution small animal imaging modalities presents researchers with the opportunity to precisely identify and describe pathological processes of the liver. To meet the demands, the objective of this study was to provide a three-dimensional illustration of the macroscopic anatomical location of the murine liver lobes and hepatic vessels using small animal imaging modalities. We analysed micro-CT images of the murine liver by integrating additional information from the published literature to develop comprehensive illustrations of the macroscopic anatomical features of the murine liver and hepatic vasculature. As a result, we provide updated three-dimensional illustrations of the macroscopic anatomy of the murine liver and hepatic vessels using micro-CT. The information presented here provides researchers working in the field of experimental liver disease with a comprehensive, easily accessable overview of the macroscopic anatomy of the murine liver

Evaluation of evidence within occupational therapy in stroke rehabilitation

Evidence-based practice creates practice that integrates research-driven evidence with clinical expertise and patients' preferences in clinical decision-making. Aim: The aim of this study was to investigate and evaluate the quality and applicability of scientific research in occupational therapy intervention related to the use of everyday life occupations and client-centred practice within stroke rehabilitation. Design: Systematic searches of research studies published in English during 2000-2007 in peer-reviewed journals were undertaken. Thirty-nine articles and one Cochrane review were appraised and the quality evaluated using an evidence taxonomy and an evidence hierarchy. Results: Evidence arose providing support for a client-centred approach, entailing outcome related to better ability to recall goals, the patients feeling more involved and able to manage more everyday life occupations after rehabilitation. There is also considerable evidence for the use of everyday life occupations in occupational therapy. Occupational therapy was evaluated as an important aspect of stroke rehabilitation improving outcomes in everyday life occupations including activities of daily living (ADL) and participation. Discussion: As research of relevance for the profession to a large extent includes qualitative research it gives rise to reflection on including more tools than the evidence hierarchy while evaluating evidence within occupational therapy

Biologically based design of an actuator system for a knee–ankle–foot orthosis

Knee–ankle–foot orthosis are systems used to restore human gait, providing stability during stance phase. A concept of actuator for knee–ankle–foot orthosis was developed based on biomechanical data. The actuator is conceived to provide mechanical means to reproduce the normal kinematics during human gait at joint level. Behaviour of the joints of the lower limb was approximated by elastic means and an actuator for each joint was designed and constructed. The rationale of the design process is presented, considering the functional aspects and aiming at a lightweight solution with low power demand. Tests performed with one patient suffering from post-poliomyelitis syndrome are presented and evidence of functional compensation during stance and swing phases with the proposed solution is given.The work presented in this paper has been partially funded through Grant IST-2001-37751 of the European Commission. The authors thank Ossur hf and Roessingh Research and Development for their contributions in materials and experimentation. The work presented in this paper has been partially funded by the European Commission.Peer reviewe