William J. Sullivan, Jr.

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https://hdl.handle.net/1805/42993
Bill Sullivan is the author of Pleased to Meet Me: Genes, Germs, and the Curious Forces That Make Us Who We Are (National Geographic Books), which has been translated into a dozen languages. Sullivan is the Showalter Professor at the Indiana University School of Medicine, where he studies infectious disease. He received his Ph.D. in Cell & Molecular Biology from the University of Pennsylvania and has published over 100 papers in scientific journals. An award-winning researcher, teacher, and science communicator, Sullivan has been featured in a wide variety of outlets, including CNN, Fox & Friends, CBS News, ESPN, The Doctors, New York Post, Wall Street Journal, TEDx, The Scientist, and many more. He has written popular science articles for National Geographic, Discover, Scientific American, Washington Post, WIRED, Psychology Today, The Conversation, and more. He is an editor and writer at PLOS SciComm, chairs the Editorial Advisory Board for ASBMB Today, and serves as a board member of the John Shaw Billings Medical History Society.

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Browsing William J. Sullivan, Jr. by Subject "Acanthamoeba"

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    Repositioning of Guanabenz in Conjugation with Gold and Silver Nanoparticles against Pathogenic Amoebae Acanthamoeba castellanii and Naegleria fowleri
    (ACS, 2019-10) Anwar, Areeba; Mungroo, Mohammad Ridwane; Anwar, Ayaz; Sullivan, William J., Jr.; Khan, Naveed Ahmed; Siddiqui, Ruqaiyyah; Pharmacology and Toxicology, School of Medicine
    Brain-eating amoebae cause devastating infections in the central nervous system of humans, resulting in a mortality rate of 95%. There are limited effective therapeutic options available clinically for treating granulomatous amoebic encephalitis and primary amoebic meningoencephalitis caused by Acanthamoeba castellanii (A. castellanii) and Naegleria fowleri (N. fowleri), respectively. Here, we report for the first time that guanabenz conjugated to gold and silver nanoparticles has significant antiamoebic activity against both A. castellanii and N. fowleri. Gold and silver conjugated guanabenz nanoparticles were synthesized by the one-phase reduction method and were characterized by ultraviolet–visible spectrophotometry and atomic force microscopy. Both metals were facilely stabilized by the coating of guanabenz, which was examined by surface plasmon resonance determination. The average size of gold nanoconjugated guanabenz was found to be 60 nm, whereas silver nanoparticles were produced in a larger size distribution with the average diameter of around 100 nm. Guanabenz and its noble metal nanoconjugates exhibited potent antiamoebic effects in the range of 2.5 to 100 μM against both amoebae. Nanoparticle conjugation enhanced the antiamoebic effects of guanabenz, as more potent activity was observed at a lower effective concentration (2.5 and 5 μM) compared to the drug alone. Moreover, encystation and excystation assays revealed that guanabenz inhibits the interconversion between the trophozoite and cyst forms of A. castellanii. Cysticdal effects against N. fowleri were also observed. Notably, pretreatment of A. castellanii with guanabenz and its nanoconjugates exhibited a significant reduction in the host cell cytopathogenicity from 65% to 38% and 2% in case of gold and silver nanoconjugates, respectively. Moreover, the cytotoxic evaluation of guanabenz and its nanoconjugates revealed negligible cytotoxicity against human cells. Guanabenz is already approved for hypertension and crosses the blood–brain barrier; the results of our current study suggest that guanabenz and its conjugated gold and silver nanoparticles can be repurposed as a potential drug for treating brain-eating amoebic infections.