Medicine and Health Sciences Commons^™

Membrane-Active Epithelial Keratin 6a Fragments (Kamps) Are Unique Human Antimicrobial Peptides With A Non-Αβ Structure., Judy T.Y. Lee, Guangshun Wang, Yu Tong Tam, Connie Tam

Journal Articles: Pathology and Microbiology

Antibiotic resistance is a pressing global health problem that threatens millions of lives each year. Natural antimicrobial peptides and their synthetic derivatives, including peptoids and peptidomimetics, are promising candidates as novel antibiotics. Recently, the C-terminal glycine-rich fragments of human epithelial keratin 6A were found to have bactericidal and cytoprotective activities. Here, we used an improved 2-dimensional NMR method coupled with a new protocol for structural refinement by low temperature simulated annealing to characterize the solution structure of these kerain-derived antimicrobial peptides (KAMPs). Two specific KAMPs in complex with membrane mimicking sodium dodecyl sulfate (SDS) micelles displayed amphipathic conformations with only …

Il-10 Plays An Important Role In The Control Of Inflammation But Not In The Bacterial Burden In S. Epidermidis Cns Catheter Infection., Yenis M. Gutierrez-Murgas, Gwenn Skar, Danielle Ramirez, Matthew Beaver, Jessica N. Snowden

Journal Articles: Pathology and Microbiology

BACKGROUND: Shunt infection is a frequent and serious complication in the surgical treatment in hydrocephalus. Previous studies have shown an attenuated immune response to these biofilm-mediated infections. We proposed that IL-10 reduces the inflammatory response to Staphylococcus epidermidis (S. epidermidis) CNS catheter infection.

METHODS: In this study, a murine model of catheter-associated S. epidermidis biofilm infection in the CNS was generated based on a well-established similar model for S. aureus. The catheters were pre-coated with a clinically derived biofilm-forming strain of S. epidermidis (strain 1457) which were then stereotactically implanted into the lateral left ventricle of 8-week-old C57BL/6 and IL-10 …

Nox2-Derived Oxidative Stress Results In Inefficacy Of Antibiotics Against Post-Influenza S. Aureus Pneumonia., Keer Sun, Vijaya Kumar Yajjala, Christopher Bauer, G. Talmon, Karl J. Fischer, Tammy Kielian, Dennis W. Metzger

Journal Articles: Pathology and Microbiology

Clinical post-influenza Staphylococcus aureus pneumonia is characterized by extensive lung inflammation associated with severe morbidity and mortality even after appropriate antibiotic treatment. In this study, we show that antibiotics rescue nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2)-deficient mice but fail to fully protect WT animals from influenza and S. aureus coinfection. Further experiments indicate that the inefficacy of antibiotics against coinfection is attributable to oxidative stress-associated inflammatory lung injury. However, Nox2-induced lung damage during coinfection was not associated with aggravated inflammatory cytokine response or cell infiltration but rather caused by reduced survival of myeloid cells. Specifically, oxidative stress increased …

Moving Towards Effective Therapeutic Strategies For Neuronal Ceroid Lipofuscinosis., Ryan D. Geraets, Seung Yon Koh, Michelle L. Hastings, Tammy Kielian, David A. Pearce, Jill M. Weimer

Journal Articles: Pathology and Microbiology

The Neuronal Ceroid Lipofuscinoses (NCLs) are a family of autosomal recessive neurodegenerative disorders that annually affect 1:100,000 live births worldwide. This family of diseases results from mutations in one of 14 different genes that share common clinical and pathological etiologies. Clinically, the diseases are subcategorized into infantile, late-infantile, juvenile and adult forms based on their age of onset. Though the disease phenotypes may vary in their age and order of presentation, all typically include progressive visual deterioration and blindness, cognitive impairment, motor deficits and seizures. Pathological hallmarks of NCLs include the accumulation of storage material or ceroid in the lysosome, …