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Sirius Red (Siriu + red)
Selected AbstractsSkin Repair Using a Porcine Collagen I/III Membrane,Vascularization and Epithelization PropertiesDERMATOLOGIC SURGERY, Issue 6 2010FALK WEHRHAN MD BACKGROUND Collagen membranes have been developed to overcome the problem of limited availability of skin grafts. Vascularization and restricted functional epithelization limit the success of bioartificial constructs. OBJECTIVE To compare the vascularization, epithelization, and integration of a porcine collagen I/III membrane with that of split-thickness skin grafts on skin wounds. MATERIALS AND METHODS In 21 adult pigs, full-thickness skin defects on the rear side of the ear healed by split-thickness skin grafting, by covering with the membrane, or by free granulation. Skin samples on postoperative days 1, 3, 7, 14, 21, and 28 were evaluated histologically (hematoxylin-eosin, Sirius Red) and using immunohistochemistry (cytokeratin 5/6, transforming growth factor beta receptor (TGF,R-III) and immunoblot (TGF,1,3, Smad2/3). Epithelial thickness and TGF,R-III-positive capillary area were quantitatively assessed. RESULTS Epithelization and vascularization in the membrane group were not significantly different from in the group treated with a split-thickness skin graft. Free granulation showed significantly slower epithelization and vascularization (p<.05). TGF,1 and Smad2/3 complex expression were high during free granulation. Matrix was distinguishable until day 7. CONCLUSIONS This membrane serves as a suitable full-thickness dermal substitute, because the membrane is vascularized faster than free granulation tissue and enables early epithelization. Geistlich Biomaterials (Wolhusen, Switzerland) provided the collagen membrane used in this study [source] 2164: Role of placental growth factor (PIGF) in wound healing after glaucoma filtration surgeryACTA OPHTHALMOLOGICA, Issue 2010T VAN BERGENArticle first published online: 23 SEP 2010 Purpose Failing filtering surgery due to excessive wound healing is a considerable challenge in ophthalmology, and largely contributes to progressive vision loss in glaucoma patients. Anti-VEGF therapy helps to prevent post-surgical scarring by inhibiting angiogenesis and collagen deposition, but does not influence inflammation (which is also an important player in postoperative wound healing). We will check the hypothesis that placental growth factor (PlGF) plays a role in scar formation after glaucoma filtration surgery, and that it may be a(n) (additional) target for improvement of the outcome of this surgery through its known anti-angiogenic and anti-inflammatory, and possibly anti-fibrotic properties. Methods The effect of an anti-PlGF antibody (ThromboGenics) will be investigated in vitro on the proliferation of endothelial cells (HUVEC), inflammatory cells (Jurkat cells) and of Tenon fibroblasts (TF). The effect of the antibody will also be investigated in vivo in a rabbit model for glaucoma surgery by measuring intra-ocular pressure (IOP), filtration bleb function and survival, and by (immuno-)histological analysis of angiogenesis (CD31), inflammation (CD45) and fibrosis (Sirius Red). Conclusion Our proposed research project will elucidate the potential role of PlGF-inhibition in the improvement of filtration surgery outcome, and will highlight any angiostatic, anti-inflammatory, and/or anti-fibrotic effects. PlGF-inhibition as an adjuvant anti-inflammatory therapy to anti-VEGF treatment in glaucoma surgery might open new perspectives for more efficient surgery. In conclusion, our project opens exciting perspectives for the treatment of the blinding condition of glaucoma, and thus might improve the visual prognosis of glaucoma patients. [source] The role of lox and LOXL2 in inflammation and fibrosis in a laser induced mouse modelACTA OPHTHALMOLOGICA, Issue 2009S VAN DE VEIRE Purpose Lysyl oxidase (LOX) and lysyl oxidase-like protein 2 (LOXL2) are involved in the cross-linking of collagen and elastin in the extracellular space. The aim of this study was to investigate the expression LOX and LOXL2 in the eye (choroidea and retina) after laser-induced chroidal neovascularization (CNV). We also want to check the anti-angiogenic, anti-inflammatory and anti-fibrotic efficacy of anti-LOX and anti-LOXL2 antibody in a mouse model of age related macular degeneration (ARMD). Methods CNV will be induced in 8 to 10 weeks old C75Bl/6 mice, by placing 3 laser spots at 9, 12 and 3 o'clock position (50µm, 0.05 s and 400mW). Two daily injection with LOX(L) antibodies or control solution (PBS-Tween 20%) will be given intraperitoneally from day 0 after lasering until day 34. Immediately after death, both eyes will be enucleated. One eye will be used to check RNA-expression of LOX and LOXL. The other eye will be used to perform different immunohistochemical stainings (HE, Sirius Red, Trichrome, CD31, CD45 and LOX(L)). Results Preliminary results showed a significant increase of LOX and LOXL2 in the choroid and retina after lasering compared to control. Conclusion ARMD remains the most common cause of irreversible vision loss in people aged 50 years and older, due to (sub-)retinal neovascularisation and scarring. It is already known that LOX and LOXL are playing a role in the cross linking of collagen and elastin, leading to an increase of fibrosis, and there is growing evidence that these molecules also play a role in neovascularisation. Therefore, a therapeutic potential of anti-LOX and/or anti-LOXL therapy can open new perspectives to treat CNV. [source] Microplasmin improves surgical outcome in a rabbit model for trabeculectomyACTA OPHTHALMOLOGICA, Issue 2009E VANDEWALLE Purpose This study was designed to study the efficacy and safety of Microplasmin as an anti-scarring agent after trabeculectomy in a rabbit model. Methods The effect of Microplasmin was investigated in vivo in a rabbit model for glaucoma surgery. Clinical outcome measures were intra-ocular pressure, bleb area and survival, side effects on slit lamp examination. Moreover, (immuno-) histochemical analysis of the eyes was performed, with quantification of inflammation (CD 45) and collagen deposition (Trichrome and Sirius Red). In the first experiment (n=10), Microplasmin anterior chamber injection was compared to placebo injection. In the second experiment (n=3), topical Microplasmin drops were compared to placebo drops. In the third experiment (n=5) the combination of Microplasmin anterior chamber injection and topical drops was compared to placebo injection and drops. All experiments were conducted in a masked observator way. Results Microplasmin significantly augmented the bleb area and survival in a rabbit model of trabeculectomy after a single anterior chamber injection or combination therapy (injection combined with drops) compared to control. Collagen deposition was borderline reduced after Microplasmin administration compared to control. No significant changes in inflammation were noticed in the anterior chamber or in the conjunctiva. Conclusion Microplasmin single injection or combination with postoperative drops improved the outcome after trabeculectomy. In a rabbit model, larger blebs were produced for a longer period compared to control, and collagen deposition tended to decrease in this small series. [source] Low coronary driving pressure early in the course of myocardial infarction is associated with subendocardial remodelling and left ventricular dysfunctionINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2007Marcia Kiyomi Koike Summary Subendocardial remodelling of the left ventricular (LV) non-infarcted myocardium has been poorly investigated. Previously, we have demonstrated that low coronary driving pressure (CDP) early postinfarction was associated with the subsequent development of remote subendocardial fibrosis. The present study aimed at examining the role of CDP in LV remodelling and function following infarction. Haemodynamics were performed in Wistar rats immediately after myocardial infarction (MI group) or sham surgery (SH group) and at days 1, 3, 7 and 28. Heart tissue sections were stained with HE, Sirius red and immunostained for ,-actin. Two distinct LV regions remote to infarction were examined: subendocardium (SE) and interstitium (INT). Myocyte necrosis, leucocyte infiltration, myofibroblasts and collagen volume fraction were determined. Compared with SH, MI showed lower CDP and LV systolic and diastolic dysfunction. Necrosis was evident in SE at day 1. Inflammation and fibroplasia predominated in SE as far as day 7. Fibrosis was restricted to SE from day 3 on. Inflammation occurred in INT at days 1 and 3, but at a lower grade than in SE. CDP correlated inversely with SE necrosis (r = ,0.65, P = 0.003, at day 1), inflammation (r = ,0.76, P < 0.001, at day 1), fibroplasia (r = ,0.47, P = 0.04, at day 7) and fibrosis (r = ,0.83, P < 0.001, at day 28). Low CDP produced progressive LV expansion. Necrosis at day 1, inflammation at days 3 and 7, and fibroplasia at day 7 correlated inversely with LV function. CDP is a key factor to SE integrity and affects LV remodelling and function following infarction. [source] Effects of the combination of rapamycin with tacrolimus or cyclosporin on experimental intimal hyperplasiaBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 11 2002Dr J. R. Waller Background: Allograft vasculopathy remains the leading cause of late allograft failure following transplantation and can be inhibited by the antiproliferative drug rapamycin. This study assessed the efficacy of combining rapamycin therapy with calcineurin inhibition. Methods: Male Sprague,Dawley rats received rapamycin 0·05 mg/kg daily and either tacrolimus 0·1 mg/kg or cyclosporin 5 mg/kg daily, and findings were compared with those in an untreated control group. Animals underwent left common carotid artery balloon angioplasty; the artery was explanted after 2 weeks. Morphometric analysis was performed on transverse sections and the intima: media ratio was calculated. Profibrotic gene expression was measured with competitive reverse transcriptase,polymerase chain reaction at 14 and 28 days. Proliferation was determined with proliferating cell nuclear antigen at 14 and 28 days. Extracellular matrix deposition was quantified with Sirius red. Results: The combination of rapamycin and tacrolimus was associated with the greatest reduction in intimal thickening. Furthermore, treatment with rapamycin and tacrolimus significantly attenuated extracellular matrix deposition compared with rapamycin and cyclosporin (P < 0·02). Conclusion: The effects of rapamycin in combination with tacrolimus were better than those observed with rapamycin and cyclosporin. © 2002 British Journal of Surgery Society Ltd [source] The effect of microplamin on wound healing after glaucoma filtration surgeryACTA OPHTHALMOLOGICA, Issue 2009T VAN BERGEN Purpose The outcome of trabeculectomy can be diminished due to a decreased bleb function secondary to blood/ fibrin clot in the aqueous outflow pathway. The aim of this study is to investigate whether the administration of Microplasmin (ThromboGenics), a recombinant protein that dissolves clot and fibrin, could lead to a better maintenance of the constructed channel, and thus improve surgical outcome after trabeculectomy. Methods The effect of Microplasmin will be investigated in vivo in a mouse model for conjunctival fibrosis and in a rabbit model for glaucoma surgery. Postoperative follow up of the animals will take place daily during the first week and two-daily until they are scarified. On specific time points animals will be sacrificed and both eyes will be enucleated. Seven-µm thin slides will be (immuno-)stained for CD45 to evaluate inflammation and for Sirius red and Trichrome to evaluate fibrosis. Results Preliminary results showed that Microplasmin significantly improved glaucoma surgery outcome in the rabbit model of aggressive scarring compared to control. Conclusion Our proposed research project will elucidate the potential role of Microplasmin in the improvement of filtration surgery outcome, and will highlight any anti-clotting, anti-inflammatory, and/or anti-fibrotic effects of this molecule. Microplasmin as an adjuvant therapy in glaucoma surgery might open new perspectives for more efficient surgery. [source] | ||||||||||