Publications by authors named "R W Keunen"

Objective: The aim of the work described here was to assess the diagnostic accuracy of a new algorithm (SGA-a) for time-domain analysis of transcranial Doppler audio signals to discriminate presumed solid and gaseous microembolic signals and artifacts (SGAs).

Methods: SGA-a was validated by human experts in an artifact cohort of 20 patients subjected to a 1-h transcranial Doppler exam before cardiac surgery (cohort 1). Emboli were validated in a cohort of 10 patients after aortic valve replacement in a 4-h monitoring period (cohort 2).

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Nanoparticles (NPs) designed for biomedical applications are coated with protein-repellent polymers. Here, we examine the penetration of rodlike NPs with narrow size distributions ( = 170 nm, = 12 nm) into multicellular tumor spheroids prepared from two human cancer cell lines. Two types of NPs with different core materials [polyferrocenylsilane and cellulose nanocrystals (CNC)] were coated with a dense brush of poly(oligoethyleneglycol methacrylate) (POEGMA), while a second CNC NP sample was coated with a linear polyethylene glycol (PEG) brush.

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We are interested in developing lanthanide nanoparticles (LnNPs) of the general formula NaLnF as high-sensitivity reagents for mass cytometry. These LnNPs must be coated to provide colloidal stability in aqueous buffer and functionality for detecting cellular biomarkers. Lipid bilayer coatings are a promising approach, but one requires an analytical technique to enable characterization of the NP coating composition as opposed to the composition of the lipid formulation used in the coating process.

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A complication of ventriculoperitoneal (VP) shunting is overdrainage or overshunting of cerebrospinal fluid, which can cause formation of hygroma but in rare cases also cervical myelopathy at a later stage. In this article, we describe a very late complication of VP shunting. We present a 75-year-old man, previously given a VP shunt at the age of 46, who developed a progressive gait disturbance and ataxia of the limbs after 27 years.

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Background: Patients with myasthenia gravis (MG) are at a higher risk of developing Takotsubo cardiomyopathy (TTC), particularly during a myasthenic crisis. Myasthenic crisis-associated TTC occurs predominantly in women. In this case report, we present a man with metastasized prostate carcinoma who developed TTC after new-onset MG.

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