Martin J. Siemerink

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The functional shift of quiescent endothelial cells into tip cells that migrate and stalk cells that proliferate is a key event during sprouting angiogenesis. We previously showed that the sialomucin CD34 is expressed in a small subset of cultured endothelial cells and that these cells extend filopodia: a hallmark of tip cells in vivo. In the present study,(More)
Angiogenesis is defined as the formation of new blood vessels from the existing vasculature. It is a highly coordinated process occurring during development of the retinal vasculature, ocular wound healing, and in pathological conditions. Complex interactions are involved between non-vascular and microvascular cells, such as endothelial cells and pericytes,(More)
The sialomucins CD34 and podocalyxin (PODXL) are anti-adhesive molecules expressed at the luminal membrane of endothelial cells of small blood vessels and facilitate vascular lumen formation in the developing mouse aorta. CD34 transcript and protein levels are increased during human angiogenesis, its expression is particularly enriched on endothelial tip(More)
Ocular diseases dominated by neovascularization, such as age-related macular degeneration (AMD), retinal vein occlusions, and diabetic retinopathy (DR), often culminate in severe visual loss and ultimately blindness. In most of these conditions, ischemic retinal areas produce abnormal amounts of angiogenic growth factors that induce excessive angiogenesis,(More)
PURPOSE To report presumed Fuchs heterochromic uveitis (FHU) associated with Rubella virus (RV)-specific intraocular antibody production in a child who was not vaccinated against rubella. DESIGN Observational case report. METHODS We examined a 13-year-old boy with chronic anterior uveitis complicated by mature cataract. Two aqueous humor (AH) samples(More)
Endothelial tip cells are leading cells at the tips of vascular sprouts coordinating multiple processes during angiogenesis. In the developing retina, tip cells play a tightly controlled, timely role in angiogenesis. In contrast, excessive numbers of tip cells are a characteristic of the chaotic pathological blood vessels in proliferative retinopathies. Tip(More)
Angiogenesis is essential during development and in pathological conditions such as chronic inflammation and cancer progression. Inhibition of angiogenesis by targeting vascular endothelial growth factor (VEGF) blocks disease progression, but most patients eventually develop resistance which may result from compensatory signalling pathways. In endothelial(More)
PURPOSE To evaluate the refractive accuracy of intraocular lens (IOL) power calculation after phacovitrectomy. SETTING Eye Hospital Zonnestraal and Department of Ophthalmology Academic Medical Center, Amsterdam, the Netherlands. DESIGN Retrospective comparative case series. METHODS Refraction results 1 month after phacovitrectomy or(More)
Orbital inflammatory disease and secondary optic neuropathy is a rare but devastating complication of long-term intranasal cocaine abuse. We describe 2 patients with a history of intranasal cocaine consumption who presented with subacute onset of unilateral vision loss from optic neuropathy and limitation of abduction in the affected eye. Magnetic resonance(More)
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