Pathology 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 …

Recurrent Mutations Of T-Cell Receptor And Co-Stimulatory Signaling Proteins In Peripheral T-Cell Lymphomas, Joseph Rohr

Theses & Dissertations

Peripheral T-cell lymphomas (PTCLs) comprise a heterogeneous group of mature T-cell neoplasms with a poor prognosis. Recently, mutations in TET2 and other epigenetic modifiers as well as RHOA have been identified in these diseases, particularly in angioimmunoblastic T-cell lymphoma (AITL). CD28 is the major co-stimulatory receptor in T-cells which, upon binding ligand, induces sustained T-cell proliferation and cytokine production when combined with T-cell receptor stimulation, through many signaling molecules including VAV1. This thesis identifies recurrent mutations in CD28 in PTCLs, as well as mutations in VAV1. Two residues of CD28 – D124 and T195 – were recurrently mutated in 11.3% …

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, …