Browsing by Author "Schiff, Steven J."

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    Approaches in cooling of resistive coil-based low-field Magnetic Resonance Imaging (MRI) systems for application in low resource settings
    (BMC Biomedical Engineering, 2021) Natukunda, Faith; Twongyirwe, Theodora M.; Schiff, Steven J.; Obungoloch, Johnes
    Magnetic Resonance Imaging (MRI), a non-invasive method for the diagnosis of diverse health conditions has experienced growing popularity over other imaging modalities like ultrasound and Computer Tomography. Initially, proof-of-concept and earlier MRI systems were based on resistive and permanent magnet technology. However, superconducting magnets have long held monopoly of the market for MRI systems with their high-field (HF) strength capability, although they present high construction, installation, and siting requirements. Such stringent prerequisites restrict their availability and use in low-middle income countries. Resistive coil-based magnet, albeit low-field (LF) in capacity, represent a plausible boost for the availability and use of MRI systems in resource constrained settings. These systems are characterized by low costs coupled with substantial image quality for diagnosis of some conditions such as hydrocephalus common is such regions. However, the nature of resistive coils causes them to heat up during operation, thus necessitating a dedicated cooling system to improve image quality and enhance system longevity. This paper explores a range of cooling methods as have been applied to resistive magnets, citing their pros and cons and areas for improvement.
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    The Bacterial and Viral Complexity of Postinfectious Hydrocephalus in Uganda
    (Science translational medicine, 2020) Paulson, Joseph N.; Williams, Brent L.; Hehnly, Christine; Mishra, Nischay; Sinnar, Shamim A.; Zhang, Lijun; Ssentongo, Paddy; Kabachelor, Edith Mbabazi; Wijetunge, Dona S. S.; Bredow, Benjamin von; Mulondo, Ronnie; Kiwanuka, Julius; Bajunirwe, Francis; Bazira, Joel; Bebell, Lisa M.; Burgoine, Kathy; Couto-Rodriguez, Mara; Ericson, Jessica E.; Erickson, Tim; Ferrari, Matthew; Gladstone, Melissa; Guo, Cheng; Haran, Murali; Hornig, Mady; Isaacs, Albert M.; Kaaya, Brian Nsubuga; Kangere, Sheila M.; Kulkarni, Abhaya V.; Kumbakumba, Elias; Li, Xiaoxiao; Limbrick, David D.; Magombe, Joshua; Morton, Sarah U.; Mugamba, John; Ng, James; Olupot, Peter Olupot; Onen, Justin; Peterson, Mallory R.; Roy, Farrah; Sheldon, Kathryn; Townsend, Reid; Weeks, Andrew D.; Whalen, Andrew J.; Quackenbush, John; Ssenyonga, Peter; Galperin, Michael Y.; Almeida, Mathieu; Atkins, Hannah; Warf, Benjamin C.; Lipkin, W. Ian; Broach, James R.; Schiff, Steven J.
    Postinfectious hydrocephalus (PIH), often following neonatal sepsis, is the most common cause of pediatric hydrocephalus world-wide, yet the microbial pathogens remain uncharacterized. Characterization of the microbial agents causing PIH would lead to an emphasis shift from surgical palliation of cerebrospinal fluid (CSF) accumulation to prevention. We examined blood and CSF from 100 consecutive cases of PIH and control cases of non-postinfectious hydrocephalus (NPIH) in infants in Uganda. Genomic testing was undertaken for bacterial, fungal, and parasitic DNA, DNA and RNA sequencing for viral identification, and extensive bacterial culture recovery. We uncovered a major contribution to PIH from Paenibacillus, upon a background of frequent cytomegalovirus (CMV) infection. CMV was only found in CSF in PIH cases. A facultatively anaerobic isolate was recovered. Assembly of the genome revealed a strain of P. thiaminolyticus. In mice, this isolate designated strain Mbale, was lethal in contrast with the benign reference strain. These findings point to the value of an unbiased pan-microbial approach to characterize PIH in settings where the organisms remain unknown, and enables a pathway towards more optimal treatment and prevention of the proximate neonatal infections.