Dr. Aaron Barnes, MD, PhD - University of Minnesota Medical School - Postdoc, Dunny Lab (Dept of Microbiology & Immunology)

Dr. Aaron Barnes

MD, PhD

University of Minnesota Medical School

Postdoc, Dunny Lab (Dept of Microbiology & Immunology)

Minneapolis, MN | United States

Main Specialties: Infectious Disease, Medical Microbiology, Pathology-Anatomic & Clinical

Additional Specialties: Clinical Pathology (Micro, Molecular)

ORCID logohttps://orcid.org/0000-0002-7014-7556

Dr. Aaron Barnes, MD, PhD - University of Minnesota Medical School - Postdoc, Dunny Lab (Dept of Microbiology & Immunology)

Dr. Aaron Barnes

MD, PhD

Introduction

Primary Affiliation: University of Minnesota Medical School - Minneapolis, MN , United States

Specialties:

Additional Specialties:

Research Interests:


View Dr. Aaron Barnes’s Resume / CV

Education

Mar 2020
University of Minnesota School of Medicine
Postdoc - Dunny Lab
Microbiology
Jul 2019
University of Minnesota School of Medicine
Resident, Clinical Pathology
Lab Medicine
Jul 2005 - May 2014
University of Minnesota Medical School Twin Cities
M.D.
Medicine
May 2014
UMN - Dept of Microbiology
Postdoc Fellow (Dunny Lab)
Microbiology (T32 training grant)
Oct 2012
University of Minnesota Medical School
Ph.D.
Microbiology

Experience

Jan 2018
MSACL (US): Best Poster Presentation Award
Presenter
Palm Springs, CA
Jun 2017
Strandjord Young Investigators Award (Grand Award finalist)
Awardee
Academy of Clinical Laboratory Physicians
Aug 2012
Presidential Scholar Award
Awardee
Microscopy Society of America (Phoenix, AZ)

Publications

14Publications

246Reads

12Profile Views

171PubMed Central Citations

Widespread Lichtheimia Infection in a Patient with Extensive Burns: Opportunities for Novel Antifungal Agents.

Mycopathologia 2019 Feb 2;184(1):121-128. Epub 2018 Jul 2.

Department of Medicine (Division of Infectious Diseases and International Medicine), University of Minnesota School of Medicine, Minneapolis, MN, 55455, USA.

The Mucorales fungi-formerly classified as the zygomycetes-are environmentally ubiquitous fungi, but generally rare causes of clinical infections. In the immunocompromised host, however, they can cause invasive, rapidly spreading infections that confer a high risk of morbidity and mortality, often despite surgical and antifungal therapy. Patients with extensive burn injuries are particularly susceptible to skin and soft-tissue infections with these organisms. Here, we present a case of Lichtheimia infection in a patient with extensive full-thickness burns that required significant and repeated surgical debridement successfully treated with isavuconazole and adjunctive topical amphotericin B washes. We also review the available literature on contemporary antifungal treatment for Lichtheimia species and related Mucorales fungi.

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http://dx.doi.org/10.1007/s11046-018-0281-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6445638PMC
February 2019
11 Reads
1.528 Impact Factor

Enterococcus faecalis readily colonizes the entire gastrointestinal tract and forms biofilms in a germ-free mouse model.

Virulence 2017 04 25;8(3):282-296. Epub 2016 Aug 25.

a Departments of Microbiology & Immunology , University of Minnesota Medical School , Minneapolis , MN , USA.

The mammalian gastrointestinal (GI) tract is a complex organ system with a twist-a significant portion of its composition is a community of microbial symbionts. The microbiota plays an increasingly appreciated role in many clinically-relevant conditions. It is important to understand the details of biofilm development in the GI tract since bacteria in this state not only use biofilms to improve colonization, biofilm bacteria often exhibit high levels of resistance to common, clinically relevant antibacterial drugs. Here we examine the initial colonization of the germ-free murine GI tract by Enterococcus faecalis-one of the first bacterial colonizers of the naïve mammalian gut. We demonstrate strong morphological similarities to our previous in vitro E. faecalis biofilm microcolony architecture using 3 complementary imaging techniques: conventional tissue Gram stain, immunofluorescent imaging (IFM) of constitutive fluorescent protein reporter expression, and low-voltage scanning electron microscopy (LV-SEM). E. faecalis biofilm microcolonies were readily identifiable throughout the entire lower GI tract, from the duodenum to the colon. Notably, biofilm development appeared to occur as discrete microcolonies directly attached to the epithelial surface rather than confluent sheets of cells throughout the GI tract even in the presence of high (>10) fecal bacterial loads. An in vivo competition experiment using a pool of 11 select E. faecalis mutant strains containing sequence-defined transposon insertions showed the potential of this model to identify genetic factors involved in E. faecalis colonization of the murine GI tract.

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http://dx.doi.org/10.1080/21505594.2016.1208890DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5411234PMC
April 2017
39 Reads
12 Citations
4.775 Impact Factor

Evaluation of the Enterococcus faecalis Biofilm-Associated Virulence Factors AhrC and Eep in Rat Foreign Body Osteomyelitis and In Vitro Biofilm-Associated Antimicrobial Resistance.

PLoS One 2015 15;10(6):e0130187. Epub 2015 Jun 15.

Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States of America; Division of Infectious Diseases, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America.

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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0130187PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4467866PMC
April 2016
29 Reads
6 Citations
3.234 Impact Factor

Multiple roles for Enterococcus faecalis glycosyltransferases in biofilm-associated antibiotic resistance, cell envelope integrity, and conjugative transfer.

Antimicrob Agents Chemother 2015 Jul 27;59(7):4094-105. Epub 2015 Apr 27.

Department of Microbiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA

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http://dx.doi.org/10.1128/AAC.00344-15DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4468649PMC
July 2015
16 Reads
12 Citations
4.480 Impact Factor

AhrC and Eep are biofilm infection-associated virulence factors in Enterococcus faecalis.

Infect Immun 2013 May 4;81(5):1696-708. Epub 2013 Mar 4.

Department of Microbiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA.

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http://dx.doi.org/10.1128/IAI.01210-12DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3648002PMC
May 2013
37 Reads
14 Citations
3.731 Impact Factor

Ultrastructure of a novel bacterial form located in Staphylococcus aureus in vitro and in vivo catheter-associated biofilms.

J Histochem Cytochem 2012 Oct 21;60(10):770-6. Epub 2012 Jul 21.

Department of Surgery, University of Minnesota, Minneapolis, MN 55455, USA.

Bacterial biofilms are ubiquitous in nature, industry, and medicine, and understanding their development and cellular structure is critical in controlling the unwanted consequences of biofilm growth. Here, we report the ultrastructure of a novel bacterial form observed by scanning electron microscopy in the luminal vegetations of catheters from patients with active Staphylococcus aureus bacteremia. This novel structure had the general appearance of a normal staphylococcal cell but up to 10 to 15 times as large. Transmission electron microscopy indicated that these structures appeared as sacs enclosing multiple normal-sized (~0.6 µm) staphylococcal forms. Using in vitro cultivated biofilms, cytochemical studies using fluorescent reagents revealed that these structures were rich in lipids and appeared within 15 min after S. aureus inoculation onto clinically relevant abiotic surfaces. Because they appeared early in biofilm development, these novel bacterial forms may represent an unappreciated mechanism for biofilm surface adherence, and their prominent lipid expression levels could explain the perplexing increased antimicrobial resistance of biofilm-associated bacteria.

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http://dx.doi.org/10.1369/0022155412457573DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3524562PMC
October 2012
12 Reads
2.370 Impact Factor

Enterococcus faecalis produces abundant extracellular structures containing DNA in the absence of cell lysis during early biofilm formation.

mBio 2012 24;3(4):e00193-12. Epub 2012 Jul 24.

Department of Microbiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA.

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http://dx.doi.org/10.1128/mBio.00193-12DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3413405PMC
October 2012
16 Reads
39 Citations
6.790 Impact Factor

Relation between antibiotic susceptibility and ultrastructure of Staphylococcus aureus biofilms on surgical suture.

Surg Infect (Larchmt) 2011 Aug;12(4):297-305

Department of Laboratory Medicine & Pathology, University of Minnesota, Minneapolis 55455, USA.

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http://dx.doi.org/10.1089/sur.2010.104DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3192185PMC
August 2011
16 Reads
7 Citations
1.721 Impact Factor

Bacterial contamination of surgical suture resembles a biofilm.

Surg Infect (Larchmt) 2010 Oct;11(5):433-9

Department of Laboratory Medicine and Pathology, University of Minnesota , Minneapolis, MN, USA.

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http://dx.doi.org/10.1089/sur.2010.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2967823PMC
October 2010
15 Reads
14 Citations
1.721 Impact Factor

Development and use of an efficient system for random mariner transposon mutagenesis to identify novel genetic determinants of biofilm formation in the core Enterococcus faecalis genome.

Appl Environ Microbiol 2008 Jun 11;74(11):3377-86. Epub 2008 Apr 11.

Department of Microbiology, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA.

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http://dx.doi.org/10.1128/AEM.02665-07DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2423031PMC
June 2008
18 Reads
32 Citations
3.670 Impact Factor

Conformational Behavior of Guest Chains in Uniaxially Stretched Poly(diethylsiloxane) Elastomers:  2H NMR and SANS

Macromolecules. 2003 36(25):9458.

Macromolecules

2H nuclear magnetic resonance (NMR) and small angle neutron scattering (SANS) data are reported for deuterated guest chains of polydiethysiloxane (PDES) in end-linked PDES networks as a function of the molecular weight of guest chains relative to that of the network elastic chains. We exploit the ability of PDES networks to form a strain-induced mesophase to demonstrate the tendency of longer guest chains to phase separate or partition selectively to the amorphous phase and the tendency of smaller guest chains to remain distributed between the mesophase and the amorphous phase. The segmental orientation of the guest chains measured via 2H NMR peak splitting can be interpreted in terms of an enthalpic orientational coupling of the chain segments in the amorphous state. SANS results show that the radius of gyration of guest chains in the unstretched networks and in the networks stretched below the mesomorphic transition remains essentially unchanged from that in the melt state. The scattering intensity from SANS patterns for networks with guest chains of any size has a peak in the direction parallel to the stretch direction that reflects the domain spacing of the lamellae in the mesophase.

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December 2003

14 Citations

Impact Factor 5.914

17 Reads

Top co-authors

Gary M Dunny
Gary M Dunny

University of Minnesota

12
Carol L Wells
Carol L Wells

University of Minnesota

5
Dawn A Manias
Dawn A Manias

University of Minnesota

4
Donavon J Hess
Donavon J Hess

University of Minnesota

3
Patrick M Schlievert
Patrick M Schlievert

University of Minnesota Medical School

3
Kristi L Frank
Kristi L Frank

Mayo Clinic College of Medicine

3
Robin Patel
Robin Patel

Mayo Clinic

2