Raphael Guzman

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We found mouse neural progenitor cells (NPCs) to have a secretory protein profile distinct from other brain cells and to modulate microglial activation, proliferation and phagocytosis. NPC-derived vascular endothelial growth factor was necessary and sufficient to exert at least some of these effects in mice. Thus, neural precursor cells may not only be(More)
No treatment currently exists to restore lost neurological function after stroke. A growing number of studies highlight the potential of stem cell transplantation as a novel therapeutic approach for stroke. In this review we summarize these studies, discuss potential mechanisms of action of the transplanted cells, and emphasize the need to determine(More)
OBJECT Moyamoya disease (MMD) is a rare cerebrovascular disease mainly described in the Asian literature. To address a lack of data on clinical characteristics and long-term outcomes in the treatment of MMD in North America, the authors analyzed their experience at Stanford University Medical Center. They report on a consecutive series of patients treated(More)
Noninvasive monitoring of stem cells, using high-resolution molecular imaging, will be instrumental to improve clinical neural transplantation strategies. We show that labeling of human central nervous system stem cells grown as neurospheres with magnetic nanoparticles does not adversely affect survival, migration, and differentiation or alter neuronal(More)
Moyamoya disease is characterized by a chronic stenoocclusive vasculopathy affecting the terminal internal carotid arteries. The clinical presentation and outcome of moyamoya disease remain varied based on angiographic studies alone, and much work has been done to study cerebral hemodynamics in this group of patients. The ability to measure cerebral blood(More)
The aim of this study was to evaluate the impact of preoperative devascularization of spinal metastases in relation to the preembolization tumor vascularization degree and in relation to the intraoperative blood loss. Twenty-four patients underwent preoperative transarterial embolization of hypervascular spinal metastases. Each tumor was assigned a(More)
BACKGROUND AND PURPOSE The inflammatory response is a critical component of ischemic stroke. In addition to its physiological role, the mechanisms behind transendothelial recruitment of immune cells also offer a unique therapeutic opportunity for translational stem cell therapies. Recent reports have demonstrated homing of neural stem cells (NSC) into the(More)
OBJECT Brain abscesses and other purulent brain processes represent potentially life-threatening conditions for which immediate correct diagnosis is necessary to administer treatment. Distinguishing between cystic brain tumors and abscesses is often difficult using conventional imaging methods. The authors' goal was to study the ability of(More)
The aim of this retrospective study was to evaluate the clinical outcome of patients with spinal dural arteriovenous fistulas (SDAVFs) that were treated with surgery, catheter embolization, or surgery after incomplete embolization. The study included 21 consecutive patients with SDAVFs of the thoracic, lumbar, or sacral spine who were treated in our(More)
Moyamoya disease is an uncommon cerebrovascular condition characterized by progressive stenosis of the bilateral internal carotid arteries with compensatory formation of an abnormal network of perforating blood vessels providing collateral circulation. The etiology and pathogenesis of moyamoya disease remain unclear. Evidence from histological studies,(More)