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Bergstrom, L.

Publications and source records attributed to Bergstrom, L..

2 recordsLinked to original sources

LubriShieldTM - a unique permanent coating for indwelling urinary catheters that impedes surface-associated uropathogens from forming biofilm

Catheter-associated urinary tract infection (CAUTI) is one of the most common healthcare-associated infections and biofilm formation plays a key role in its pathogenesis. Indwelling medical devices introduce ideal pathways inside the body for invading pathogens and feature surfaces conducive to biofilm development. These devices are the root cause of severe clinical infections often recalcitrant to antimicrobials. When bacteria and fungi switch to biofilm mode of growth, they produce a matrix in the form of extracellular polymeric substances (EPS). This creates a unique environment for growing virulent colonizers and persisting cells while also forming a shielding barrier against immune system attacks, antimicrobial agents and mechanical removal by fluid shear forces. To address this challenge, LubriShield TM - a novel permanent coating was invented, and evenly applied to both the internal and external surfaces of indwelling urinary Foley catheters. Without releasing active substances, it effectively prevented pathogens from producing biofilm. The coating was superhydrophilic and incorporated a proprietary anti-fouling ligand, which created a surface that significantly inhibited up to 99% of colonizing uropathogens from forming biofilm for the duration of use without any microbial killing (p< 0.001). The predominant uropathogens, including Gram-positive and Gram-negative as well as Candida albicans, were inhibited from forming biofilm on the LubriShieldTM coated surfaces for up to 14 days in artificial urine medium. After challenging the adhering bacteria in a glass bladder flow model, the coating still significantly reduced biofilm formation by 83% (p<0.001). The growth mode and emergent properties of adhering bacteria on uncoated silicone catheter surfaces were compared with those on LubriShieldTM coated surfaces. RNA-seq analysis revealed that gene expression associated with microbial EPS formation was significantly downregulated on the coated surfaces. Additionally, microorganisms adhering to LubriShieldTM coated catheters were 46% more susceptible to antibiotics compared to those on uncoated silicone catheters (p<0.01).

microbiology↗

TeoNAM: a nested association mapping population for domestication and agronomic trait analysis in maize

Recombinant inbred lines (RILs) are an important resource for mapping genes controlling complex traits in many species. While RIL populations have been developed for maize, a maize RIL population with multiple teosinte inbred lines as parents has been lacking. Here, we report a teosinte nested association mapping population (TeoNAM), derived from crossing five teosinte inbreds to the maize inbred line W22. The resulting 1257 BC1S4 RILs were genotyped with 51,544 SNPs, providing a high-density genetic map with a length of 1540 cM. On average, each RIL is 15% homozygous teosinte and 8% heterozygous. We performed joint linkage mapping (JLM) and genome-wide association study (GWAS) for 22 domestication and agronomic traits. A total of 255 QTLs from JLM were identified with many of these mapping to known genes or novel candidate genes. TeoNAM is a useful resource for QTL mapping for the discovery of novel allelic variation from teosinte. TeoNAM provides the first report that PROSTRATE GROWTH1, a rice domestication gene, is also a QTL associated with tillering in teosinte and maize. We detected multiple QTLs for flowering time and other traits for which the teosinte allele contributes to a more maize-like phenotype. Such QTL could be valuable in maize improvement.

genetics↗