Durable engraftment of genetically modified FVIII-secreting autologous bone marrow stromal cells in the intramedullary microenvironment.

Genetically modified FVIII-expressing autologous bone marrow-derived mesenchymal stromal cells (BMSCs) could cure haemophilia A. However, culture-expanded BMSCs engraft poorly in extramedullary sites. Here, we compared the intramedullary cavity, skeletal muscle, subcutaneous tissue and systemic circulation as tissue microenvironments that could support durable engraftment of FVIII-secreting BMSC in vivo.

Microarray profiling shows distinct differences between primary tumors and commonly used preclinical models in hepatocellular carcinoma.

Background: Despite advances in therapeutics, outcomes for hepatocellular carcinoma (HCC) remain poor and there is an urgent need for efficacious systemic therapy. Unfortunately, drugs that are successful in preclinical studies often fail in the clinical setting, and we hypothesize that this is due to functional differences between primary tumors and commonly used preclinical models. In this study, we attempt to answer this question by comparing tumor morphology and gene expression profiles between primary tumors, xenografts and HCC cell lines.

Intravoxel incoherent imaging of renal fibrosis induced in a murine model of unilateral ureteral obstruction.

Purpose: To evaluate non-invasive imaging biomarkers for assessing renal fibrosis. DWI is used to assess renal function; intravoxel incoherent motion (IVIM) provides additional measures of perfusion-related diffusion (D*, blood flow; f, perfusion fraction). We aim to determine if reduced ADC seen in renal fibrosis is attributable to perfusion-related diffusion changes or to known reduction in tissue diffusivity (D).

Stepwise training for reconstructive microsurgery: the journey to becoming a confident microsurgeon in singapore.

Microsurgery training in Singapore began in 1980 with the opening of the Experimental Surgical Unit. Since then, the unit has continued to grow and have held microsurgical training courses biannually. The road to becoming a full-fledged reconstructive surgeon requires the mastering of both microvascular as well as flap raising techniques and requires time, patience and good training facilities.

A porcine model of selective retinal capillary closure induced by embolization with fluorescent microspheres.

Purpose: To investigate the feasibility of creating an animal model of selective retinal capillary closure to mimic the capillary closure that occurs in diabetic retinopathy.

Methods: Fluorescent microspheres of 10- or 15-μm diameter were delivered to one eye of anesthetized pigs via a customized cannula advanced through the carotid arterial system to the origin of the external ophthalmic artery that supplies blood to the eye in this species. After preliminary trials in 10 pigs, embolization was performed in one eye of 34 animals that were allowed to survive for 7, 14, or 28 days.

Effective inhibition of xenografts of hepatocellular carcinoma (HepG2) by rapamycin and bevacizumab in an intrahepatic model.

Purpose: Hepatocellular carcinoma (HCC) displays a characteristic hypervascularity and depends on angiogenesis for tumor growth, which thus provides a potential target for therapeutic approaches to HCC. In this study, through the use of combined micro-positron emission tomography (PET)/computed tomography (CT), we investigate if such a combined targeting of vascular endothelial growth factor (VEGF) activity and expression might retard HCC growth in an orthotopic intrahepatic xenograft model.

Procedures: Xenograft models were created by intraportal vein injection of HepG2 cell suspensions in severe combined immunodeficient mice.

Platelet-rich plasma has no effect on increasing free fat graft survival in the nude mouse.

Background: Free fat grafts have an unpredictable survival rate, which may be dependent on host bed vascularity. Therefore, the authors hypothesized that the presence of growth factors in platelet-rich plasma (PRP), may enhance free fat graft survival.

Methods: Free fat grafts and autologous PRP were harvested from a healthy female and processed using the Coleman technique and the Medtronic Magellan system respectively.

Which is the optimal risk stratification system for surgically treated localized primary GIST? Comparison of three contemporary prognostic criteria in 171 tumors and a proposal for a modified Armed Forces Institute of Pathology risk criteria.

Background: This study aims to validate and compare the performance of the National Institute of Health (NIH) criteria, Huang modified NIH criteria, and Armed Forces Institute of Pathology (AFIP) risk criteria for gastrointestinal stromal tumors (GISTs) in a large series of localized primary GISTs surgically treated at a single institution to determine the ideal risk stratification system for GIST.

Methods: The clinicopathological features of 171 consecutive patients who underwent surgical resection for GISTs were retrospectively reviewed. Statistical analyses were performed to compare the prognostic value of the three risk criteria by analyzing the discriminatory ability linear trend, homogeneity, monotonicity of gradients, and Akaike information criteria.

Structural stability of neoangiogenic intramyocardial microvessels supports functional recovery in chronic ischemic myocardium.

We hypothesize that combining angiopoietin-1 (ANG-1) or ANG-2 with vascular endothelial growth factor (VEGF) improves myocardial perfusion and contractile function by modulating vascular adaptation of neoangiogenic microvessels in a chronic ischemic swine model. Four weeks after occlusion of the left circumflex coronary artery (LCx), animals were injected with AdVEGF(165) (n=6), AdVEGF(165)+AdANG-1 (n=6), AdVEGF(165)+AdANG-2 (n=6) or control vector (n=5) into the left ventricular posterolateral wall. Regional perfusion by fluorescent microspheres and segmental myocardial tissue velocity by tissue Doppler imaging (TDI) were assessed at baseline, 4 weeks post occlusion and 4 weeks post therapy.

Intraabdominal schwannomas: a single institution experience.

Introduction: Intraabdominal schwannomas are rare, benign tumors. This study presents a single institution experience with 12 such tumors.

Methods: Between 1991 to 2006, 12 patients with a pathologically proven intraabdominal schwannoma were identified from a series of 216 mesenchymal tumors and were reviewed retrospectively.

Long-term changes in hepatobiliary physiology after Roux-en-Y hepaticojejunostomy.

Hepaticojejunostomy (HJ) is a common operation used to by-pass extrahepatic biliary obstructions and to establish biliary-enteric continuity after resections for benign and malignant diseases. Little is known about the effect of this procedure on hepatobiliary physiology. The aim of the present study was to investigate in a swine model the changes in biliary dynamics, bile composition, and hepatic histology induced by Roux-Y HJ.

A novel biodegradable biliary stent in the normal duct hepaticojejunal anastomosis: an 18-month follow-up in a large animal model.

Creating a well-functioning hepaticojejunostomy (HJ) anastomosis with nondilated bile ducts remains a challenge. Our aim was to study the use in a large animal model of a novel, braided polylactide barium sulfate biodegradable biliary stent (BDBS) without external connection and with no need for later removal. Fifty swine were randomly operated on for Roux-Y HJ with or without BDBS in the anastomosis, and followed up (dynamic biligraphy, x-ray, serum determinations, anastomosis inner diameter, and histology) for 1.

Angiopoietin-1 promotes functional neovascularization that relieves ischemia by improving regional reperfusion in a swine chronic myocardial ischemia model.

This study investigates the long-term angiogenic effects of ANG-1 and VEGF in a swine chronic myocardial ischemia model. Four-weeks after gradual occlusion of the left circumflex coronary artery by ameroid constrictor, animals were injected with recombinant adenoviral vectors carrying either human ANG-1 (n=9), human VEGF(165) (n=10) or empty vector (n=7) into the left ventricle free wall supplied by the constricted artery. Left ventricular perfusion in animals that received AdANG-1 (3.