Publications by authors named "Stephen Karlik"

Development of pharmacotherapies that promote remyelination is a high priority for multiple sclerosis (MS), due to their potential for neuroprotection and restoration of function through repair of demyelinated lesions. A novel preparation of clean-surfaced, faceted gold nanocrystals demonstrated robust remyelinating activity in response to demyelinating agents in both chronic cuprizone and acute lysolecithin rodent animal models. Furthermore, oral delivery of gold nanocrystals improved motor functions of cuprizone-treated mice in both open field and kinematic gait studies.

View Article and Find Full Text PDF

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system, in which the release of reactive oxygen species by infiltrating immune cells contributes to demyelination. American ginseng ( Panax quinquefolius ) is a natural health product with numerous beneficial properties, including anti-inflammatory and anti-oxidant effects. The purpose of this study was to determine whether ginseng could influence the course of the disease experimental autoimmune encephalomyelitis (EAE), an animal model of MS.

View Article and Find Full Text PDF

What is the origin of the complex vascular changes that exist in the CNS lesions of Multiple Sclerosis (MS)? From the beginning of the study of the pathological changes in MS in the 19th century, lesions were seen to be associated with veins. On a microscopic level, there have been numerous pathological changes to these vessels including altered structure and permeability, fibrinolysis, iron-related alterations and collagen deposition. Vascular changes in inflammatory conditions outside the CNS are well documented and we hypothesize that angiogenesis (the generation of new blood vessels from existing) is an integral process of lesion development and spread in MS.

View Article and Find Full Text PDF

The precise mechanism-of-action of thalidomide remains uncertain and might differ between diseases and under different clinical condition. With implications in the treatment of a variety of inflammatory and autoimmune diseases, as well as for use as an anticancer agent, alone or in combination with established therapeutics, it is clear that thalidomide and its derivatives deserve further scrutiny. In particular, thalidomide was shown to be effective in a mouse model of multiple sclerosis (MS), an autoimmune inflammatory disorder, called experimental autoimmune encephalomyelitis (EAE).

View Article and Find Full Text PDF

Purpose: To determine the relationship between hemoglobin levels and attenuation measurements of the superior sagittal sinus (SSS) on unenhanced computed tomography (UECT). Secondly, to determine if SSS attenuation values are normally distributed such that measurements below and above certain thresholds are suggestive of pathology, such as anemia or acute venous thrombosis respectively.

Methods: Institutional review board approval was obtained for retrospective review of adult patients having both an UECT head examination and a complete blood count within 24 h of the scan.

View Article and Find Full Text PDF

The present work deals with the synthesis of a new series of thalidomide derivatives for therapeutic applications. These compounds were evaluated in vitro on a human endothelial cell line EA.hy926 for their antiproliferative potential and in vivo on an experimental animal multiple sclerosis model called EAE as angiogenesis inhibitors.

View Article and Find Full Text PDF

Purpose: To determine the contribution of blood-derived macrophages to the signal loss observed in MR images of inflammatory lesions in experimental autoimmune encephalomyelitis (EAE).

Materials And Methods: A relapsing-remitting form of EAE was induced in transgenic mice that express enhanced green fluorescent protein (EGFP) specifically in hematopoietic cells of the myelomonocytic lineage. Animals were injected with Feridex, a superparamagnetic iron oxide (SPIO) nanoparticle, 24 hours prior to in vivo MRI.

View Article and Find Full Text PDF

Objective: Our objective was to present the MR and MR spectroscopy imaging findings of a 3,200-year-old preserved brain from an Egyptian mummy.

Materials And Methods: In this work, the morphology of the intact specimen was examined by MRI at 1.5 T.

View Article and Find Full Text PDF

Purpose: To directly correlate spinal cord pathology of guinea pigs with experimental allergic encephalomyelitis (EAE) to the MRI data obtained at 1.5T.

Materials And Methods: Spinal cords from EAE animals were imaged in vivo with the following MRI sequences: T2-FSE, PD-FSE, fluid-attenuated inversion recovery (FLAIR)-FSE, T2-CSE, T1-CSE, T1-CSE + gadolinium-DTPA (Gd-DTPA), PD-CSE, and short-tau inversion recovery (STIR)-FSE.

View Article and Find Full Text PDF

Purpose: To image and dissect the lumbar spinal cord of guinea pigs with chronic-progressive experimental allergic encephalomyelitis (CP-EAE) and directly correlate the pathology to the magnetic resonance (MR) image data obtained at 4 T and determine if these MR contrasts can accurately differentiate a specific type of pathology from control tissue.

Materials And Methods: The amount of inflammation, demyelination, and axonal pathology were quantified in the whole cord cross sections. The signal intensities (SIs) for 228 individual regions of interest (ROIs) (normal-appearing white matter (NAWM) and tissue containing inflammation with or without demyelination) were measured directly from the corresponding area on the MR images.

View Article and Find Full Text PDF

Characteristic pathological features of multiple sclerosis (MS) include inflammation, demyelination and axonal and oligodendrocyte loss. In addition, lesions can also have a significant vascular component. In this review, morphological, biochemical and radiological evidence is presented suggesting angiogenesis as a potential focus for investigation in MS.

View Article and Find Full Text PDF

Objective: To determine the costs for 1000 randomized interventional angiographic procedures.

Methods: An 9-page paper form was used to manually record the consumables, technologist time, room occupancy time and recovery room time for 80 different procedures collected over a 2-year period. The average cost for expendables per procedure was calculated for procedures that occurred 5 or more times.

View Article and Find Full Text PDF