Browsing by Author "Childers, Christopher"

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    Brown marmorated stink bug, Halyomorpha halys (Stål), genome: putative underpinnings of polyphagy, insecticide resistance potential and biology of a top worldwide pest
    Sparks, Michael E.; Bansal, Raman; Benoit, Joshua B.; Blackburn, Michael B.; Chao, Hsu; Chen, Mengyao; Cheng, Sammy; Childers, Christopher; Dinh, Huyen; Doddapaneni, Harsha V.; Dugan, Shannon; Elpidina, Elena N.; Farrow, David W.; Friedrich, Markus; Gibbs, Richard A.; Hall, Brantley; Han, Yi; Hardy, Richard W.; Holmes, Christopher J.; Hughes, Daniel S. T.; Ioannidis, Panagiotis; Cheatle Jarvela, Alys M.; Johnston, J. Spencer; Jones, Jeffery W.; Kronmiller, Brent A.; Kung, Faith; Lee, Sandra L.; Martynov, Alexander G.; Masterson, Patrick; Maumus, Florian; Munoz-Torres, Monica; Murali, Shwetha C.; Murphy, Terence D.; Muzny, Donna M.; Nelson, David R.; Oppert, Brenda; Panfilio, Kristen A.; Paula, Débora P.; Pick, Leslie; Poelchau, Monica F.; Qu, Jiaxin; Reding, Katie; Rhoades, Joshua H.; Rhodes, Adelaide; Richards, Stephen; Richter, Rose; Robertson, Hugh M.; Rosendale, Andrew J.; Tu, Zhijian Jake; Velamuri, Arun S.; Waterhouse, Robert M.; Weirauch, Matthew T.; Wells, Jackson T.; Werren, John H.; Worley, Kim C.; Zdobnov, Evgeny M.; Gundersen-Rindal, Dawn E. (2020-03-14)
    Background Halyomorpha halys (Stål), the brown marmorated stink bug, is a highly invasive insect species due in part to its exceptionally high levels of polyphagy. This species is also a nuisance due to overwintering in human-made structures. It has caused significant agricultural losses in recent years along the Atlantic seaboard of North America and in continental Europe. Genomic resources will assist with determining the molecular basis for this species’ feeding and habitat traits, defining potential targets for pest management strategies. Results Analysis of the 1.15-Gb draft genome assembly has identified a wide variety of genetic elements underpinning the biological characteristics of this formidable pest species, encompassing the roles of sensory functions, digestion, immunity, detoxification and development, all of which likely support H. halys’ capacity for invasiveness. Many of the genes identified herein have potential for biomolecular pesticide applications. Conclusions Availability of the H. halys genome sequence will be useful for the development of environmentally friendly biomolecular pesticides to be applied in concert with more traditional, synthetic chemical-based controls.
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    Catheter-based Medical Device Biofilm Ablation Using Histotripsy: A Parameter Study
    Morse, Ryan; Childers, Christopher; Nowak, Elizabeth; Rao, Jayasimha; Vlaisavljevich, Eli (Elsevier, 2023-07-01)
    OBJECTIVE: Biofilm formation in medical catheters is a major source of hospital-acquired infections which can produce increased morbidity and mortality for patients. Histotripsy is a non-invasive, non-thermal focused ultrasound therapy and recently has been found to be effective at removal of biofilm from medical catheters. Previously established histotripsy methods for biofilm removal, however, would require several hours of use to effectively treat a full-length medical catheter. Here, we investigate the potential to increase the speed and efficiency with which biofilms can be ablated from catheters using histotripsy. METHODS: Pseudomonas aeruginosa (PA14) biofilms were cultured in in vitro Tygon catheter mimics and treated with histotripsy using a 1 MHz histotripsy transducer and a variety of histotripsy pulsing rates and scanning methods. The improved parameters identified in these studies were then used to explore the bactericidal effect of histotripsy on planktonic PA14 suspended in a catheter mimic. RESULTS: Histotripsy can be used to remove biofilm and kill bacteria at substantially increased speeds compared with previously established methods. Near-complete biofilm removal was achieved at treatment speeds up to 1 cm/s, while a 4.241 log reduction in planktonic bacteria was achieved with 2.4 cm/min treatment. CONCLUSION: These results represent a 500-fold increase in biofilm removal speeds and a 6.2-fold increase in bacterial killing speeds compared with previously published methods. These findings indicate that histotripsy shows promise for the treatment of catheter-associated biofilms and planktonic bacteria in a clinically relevant time frame.
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    Focused Ultrasound Biofilm Ablation: Investigation of Histotripsy for the Treatment of Catheter-Associated Urinary Tract Infections (CAUTIs)
    Childers, Christopher; Edsall, Connor; Gannon, Jessica; Whittington, Abby R.; Muelenaer, Andre A.; Rao, Jayasimha; Vlaisavljevich, Eli (IEEE, 2021-09-01)
    Urinary catheters often become contaminated with biofilms, resulting in catheter-associated urinary tract infections (CAUTIs) that adversely affect patient outcomes. Histotripsy is a non-invasive focused ultrasound therapy previously developed for the non-invasive ablation of cancerous tumors and soft tissues. Histotripsy has also previously shown the ability to treat biofilms on glass slides and surgical meshes. Here, we investigate the potential of histotripsy for the treatment of CAUTIs for the first time in vitro. Clinically relevant catheter materials (Tygon, Silicone, and latex catheter mimics) and commonly used clinical catheters were tested to determine the feasibility of producing luminal histotripsy bubble clouds. A Pseudomonas aeruginosa (strain PA14) biofilm model was developed and tested to produce luminal biofilms in an in vitro Tygon catheter mimic. This model was treated with histotripsy to determine the ability to remove a luminal biofilm. Finally, the bactericidal effects of histotripsy were tested by treating PA14 suspended inside the Tygon catheter mimic. Results showed that histotripsy produced precise luminal cavitation within all tested catheter mimics and clinical catheters. Histotripsy treatment of a PA14 biofilm with histotripsy reduced luminal biofilm OD590 signal down to background levels. Further, the treatment of suspended PA14 in LB showed a 3.45±0.11 log10 reduction in CFU/mL after 6 histotripsy scans across the catheter mimics. Overall, the results of this study demonstrate the potential of histotripsy to provide a new modality for removing bacterial biofilms from catheter-based medical devices and suggest that additional work is warranted to investigate histotripsy for the treatment of CAUTIs and other biomaterial-associated infections.
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    Particle-mediated Histotripsy for the Targeted Treatment of Intraluminal Biofilms in Catheter-based Medical Devices
    Childers, Christopher; Edsall, Connor; Mehochko, Isabelle; Mustafa, Waleed; Yuksel Durmaz, Yasemin; Klibanov, Alexander L.; Rao, Jayasimha; Vlaisavljevich, Eli (American Association for the Advancement of Science (AAAS), 2022-08-09)
    Objective: This paper is an initial work towards developing particle-mediated histotripsy (PMH) as a novel method of treating catheter-based medical device (CBMD) intraluminal biofilms. Impact Statement: CBMDs commonly become infected with bacterial biofilms leading to medical device failure, infection, and adverse patient outcomes. Introduction: Histotripsy is a noninvasive focused ultrasound ablation method that was recently proposed as a novel method to remove intraluminal biofilms. Here, we explore the potential of combining histotripsy with acoustically active particles to develop a PMH approach that can noninvasively remove biofilms without the need for high acoustic pressures or real-time image guidance for targeting. Methods: Histotripsy cavitation thresholds in catheters containing either gas-filled microbubbles (MBs) or fluid-filled nanocones (NCs) were determined. The ability of these particles to sustain cavitation over multiple ultrasound pulses was tested after a series of histotripsy exposures. Next, the ability of PMH to generate selective intraluminal cavitation without generating extraluminal cavitation was tested. Finally, the biofilm ablation and bactericidal capabilities of PMH were tested using both MBs and NCs. Results: PMH significantly reduced the histotripsy cavitation threshold, allowing for selective luminal cavitation for both MBs and NCs. Results further showed PMH successfully removed intraluminal biofilms in Tygon catheters. Finally, results from bactericidal experiments showed minimal reduction in bacteria viability. Conclusion: The results of this study demonstrate the potential for PMH to provide a new modality for removing bacterial biofilms from CBMDs and suggest that additional work is warranted to develop histotripsy and PMH for treatment of CBMD intraluminal biofilms.
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    Unique features of a global human ectoparasite identified through sequencing of the bed bug genome
    Benoit, Joshua B.; Adelman, Zach N.; Reinhardt, Klaus; Dolan, Amanda M.; Poelchau, Monica; Jennings, Emily C.; Szuter, Elise M.; Hagan, Richard W.; Gujar, Hemant; Shukla, Jayendra Nath; Zhu, Fang; Mohan, M.; Nelson, David R.; Rosendale, Andrew J.; Derst, Christian; Resnik, Valentina; Wernig, Sebastian; Menegazzi, Pamela; Wegener, Christian; Peschel, Nicolai; Hendershot, Jacob M.; Blenau, Wolfgang; Predel, Reinhard; Johnston, Paul R.; Ioannidis, Panagiotis; Waterhouse, Robert M.; Nauen, Ralf; Schorn, Corinna; Ott, Mark-Christoph; Maiwald, Frank; Johnston, J. Spencer; Gondhalekar, Ameya D.; Scharf, Michael E.; Peterson, Brittany F.; Raje, Kapil R.; Hottel, Benjamin A.; Armisen, David; Crumiere, Antonin Jean Johan; Refki, Peter Nagui; Santos, Maria Emilia; Sghaier, Essia; Viala, Severine; Khila, Abderrahman; Ahn, Seung-Joon; Childers, Christopher; Lee, Chien-Yueh; Lin, Han; Hughes, Daniel S. T.; Duncan, Elizabeth J.; Murali, Shwetha C.; Qu, Jiaxin; Dugan, Shannon; Lee, Sandra L.; Chao, Hsu; Dinh, Huyen; Han, Yi; Doddapaneni, Harshavardhan; Worley, Kim C.; Muzny, Donna M.; Wheeler, David; Panfilio, Kristen A.; Jentzsch, Iris M. Vargas; Vargo, Edward L.; Booth, Warren; Friedrich, Markus; Weirauch, Matthew T.; Anderson, Michelle A. E.; Jones, Jeffery W.; Mittapalli, Omprakash; Zhao, Chaoyang; Zhou, Jing-Jiang; Evans, Jay D.; Attardo, Geoffrey M.; Robertson, Hugh M.; Zdobnov, Evgeny M.; Ribeiro, Jose M. C.; Gibbs, Richard A.; Werren, John H.; Palli, Subba R.; Schal, Coby; Richards, Stephen (Nature, 2016-02-02)
    The bed bug, Cimex lectularius, has re-established itself as a ubiquitous human ectoparasite throughout much of the world during the past two decades. This global resurgence is likely linked to increased international travel and commerce in addition to widespread insecticide resistance. Analyses of the C. lectularius sequenced genome (650Mb) and 14,220 predicted protein-coding genes provide a comprehensive representation of genes that are linked to traumatic insemination, a reduced chemosensory repertoire of genes related to obligate hematophagy, host–symbiont interactions, and several mechanisms of insecticide resistance. In addition, we document the presence of multiple putative lateral gene transfer events. Genome sequencing and annotation establish a solid foundation for future research on mechanisms of insecticide resistance, human–bed bug and symbiont–bed bug associations, and unique features of bed bug biology that contribute to the unprecedented success of C. lectularius as a human ectoparasite