Session A: 9AM – 10:30AM
Health and Medicine. Session A – Oral Presentations, Dumke, Alumni House
SESSION A (9:00-10:30AM)
Location: DUmke Room, Alumni House
Preoperative Skin Preparation does not eradicate Deep-Dwelling Microflora; using two models to quantify bioburden from porcine skin
Abbey Blair, University of Utah
Faculty Mentor Dustin Williams, University of Utah
SESSION A 9:00-9:15AM
Dumke, Alumni House
Health and Medicine
Clinical Preoperative Skin Preparation (PSPs) kits are the standard of care for skin disinfection prior to surgery and the most important method of infection prevention. However, we have discovered that the antiseptics contained in these kits do not eradicate the natural flora that live in the deep regions of the skin. FDA approved PSPs fail the 2-3 log10 reduction required by the FDA when full-thickness skin samples are used on Yorkshire pigs [1]. We hypothesized that the method with which the PSP are tested is directly correlated with the log reduction result. To test this, we compared two skin sampling methods: the FDA required process, the cup scrub method, and a new procedure called the tissue blend method. The cup scrub method consists of placing a sterile cylinder on the skin that has been cleaned with antiseptic. Broth is added to the cylinder and the skin is agitated within the cup. The bacteria in the broth is then quantified. In contrast, the tissue blend method is performed by cutting out full-thickness skin samples from the backs of pigs. These tissue samples are blended, and then the homogenized tissue is quantified. We performed the cup scrub and tissue blend methods on the backs of 7 Yorkshire pigs following alternating scrubs of 4% chlorhexidine gluconate (CHG) and alcohol (n=5/pig). The cup scrub and tissue blend methods were also performed on control skin as a relative baseline (n=5/pig). With 4 treatment groups, 20 samples were taken from each animal for a total of 140 samples. The average log reduction for the cup scrub and tissue blend methods were 1.57 +/- 0.45 CFU/cm2and 0.23 +/- 0.48 CFU/cm2, respectively. When analyzing the data, CHG appears to decrease the bioburden following PSP application when using the cup scrub method, however the tissue blend method shows that it is not killing bacteria dwelling deep in the skin, ultimately resulting in infection risk. This research is fundamental for the development of new PSP technology that eradicates deep dwelling flora.
References:
Duffy, H.R.; Godfrey, R.W.; Williams, D.L.; Ashton, N.N. A Porcine Model for the Development and Testing of Preoperative Skin Preparations. Microorganisms 2022, 10, x. https://doi.org/10.3390/xxxxx
Reducing Drug Adsorption in Extracorporeal Membrane Oxygenation (ECMO) Circuits: Propofol Extraction and Analysis
Oliver Hubbard, University of Utah
Faculty Mentor Hamid Ghandehari, University of Utah
SESSION A 9:20-9:35AM
Dumke, Alumni House
Health and Medicine
Background: Extracorporeal membrane oxygenation (ECMO) is a life-saving technology for many critically ill patients. Unfortunately, ECMO has a >40% mortality rate, partly due to lack of established dosing guidelines. Dosing is different in this population due to drug interactions with the ECMO circuit. Drugs can be adsorbed by the ECMO circuit via hydrophobic and electrostatic interactions, thereby decreasing the amount of drug available to the patient. Micellar encapsulation of drugs may prevent adsorption. Methods: Two types of propofol were compared in an ECMO ex-vivo system: the clinical formulation of propofol and micelle-encapsulated propofol. The ECMO system consisted of a reservoir, pump, and oxygenator, as well as ports for drug administration and sample collection. The ECMO systems were dosed with either clinical or micellar propofol, and drug concentrations were measured over time using an optimized High Performance Liquid Chromatography (HPLC) assay. Each drug was measured in triplicate. % Recovery at each timepoint was calculated by comparing the concentration at a given timepoint with initial concentration at 1 minute. Data was reported as the mean percent recovery with 95% confidence intervals. Results: Adsorption of propofol was significantly reduced (P<0.01) in micellar propofol compared to clinical propofol at earlier time points where 40% of the drug was recovered in case of micellar propofol compared to only 24% in case of clinical propofol at 30-minute time point. Conclusion: Micellar encapsulation significantly reduced drug adsorption in the ECMO circuit. The clinical significance of this reduction is not clear. Additional studies to optimize micellar encapsulation and decrease adsorption are needed.
Effects of Blueberries Supplementation on Oral Dysbiosis
Nizhoni Porter, University of Utah
Faculty Mentor Anandh Velayutham , University of Utah
SESSION A 9:40-9:55AM
Dumke, Alumni House
Health and Medicine
The gut and oral cavity are the two most significant microbial habitats and are closely connected through the digestive pathway. Evidence indicates microbial transmission (oral-to-gut and gut-to-oral) regulates the pathogenesis of diseases such as cancer and is mediated through the oral-gut microbiome axis. An imbalance in the oral microbes (dysbiosis) is implicated in oral diseases and systemic diseases such as inflammatory bowel disease, cardiovascular disease, and Alzheimer’s disease. Our lab recently showed that dietary supplementation of blueberries improves diabetes-induced gut dysbiosis. Phytochemicals such as anthocyanins in blueberries act as prebiotics and promote the growth of beneficial gut microbes. Dietary blueberries increased the abundance of commensal microbes and decreased the abundance of opportunistic microbes in diabetic mice. In the proposed study, we will evaluate whether supplementation of blueberry improves a high-fat diet and antibiotics-induced oral dysbiosis in a preclinical model. Mice will be divided into four groups: Control (C), High Fat Diet-fed (HF), High Fat Diet-fed with antibiotics (HFA), and High Fat Diet-fed with blueberry supplementation and antibiotics (HBA). The Antibiotics will be distributed to the mice in the drinking water. The oral and gut microbiomes will be analyzed using 16s rRNA amplification. Due to the probiotic effect of anthocyanins and the translocation of bacteria between the oral and gut microbiota, this correlation could help replenish the gut and oral microbiome once destroyed or altered and, therefore, aid in creating a healthier immune system. Our study will identify whether dietary blueberries improve oral dysbiosis by modulating the oral-gut microbiome axis.
Supplementation of Blueberries Attenuates High-Fat-Diet and Antibiotics Induced Gut Inflammation
Keaton Rosquist, University of Utah
Faculty Mentor Anandh Velayutham, University of Utah
SESSION A 10:00-10:15AM
Dumke, Alumni House
Health and Medicine
Background: Obesity has currently been a growing health concern that has ranged across the world. Diet-induced obesity drives gut inflammation through the production of cytokines and alteration in gut microbiota. High-fat diet (HFD) favors the conditions that lead to gut inflammation with an increased gut epithelial permeability, allowing for higher chances of gastrointestinal disorders. Antibiotic usages interrupt gut symbiosis and further exacerbate HFD-induced complications. Evidence indicates that HFD with antibiotics increases the risk of pre-inflammatory bowel disease (IBD). Blueberries contain bioactive flavonoid compounds called anthocyanins which possess antioxidant and anti-inflammatory properties. We assessed whether dietary blueberry improves HFD- and antibiotics-induced gut inflammation. Methods: Male C57BL/6J mice (7 weeks old) were divided into three groups: (1) control mice consumed standard diet (C), (2) mice consumed HFD and treated with antibiotics in drinking water (HFA), (3) mice consumed blueberry supplemented HFD and treated with antibiotics (HFAB) for 12 weeks. Gut inflammation was assessed by measuring the mRNA expression of inflammatory markers (IL-1β, IL-6, iNOS, and MCP-1) using qPCR. The total RNA was isolated from the colon using RNeasy plus mini kit, cDNA was synthesized using RT-PCR kit, and the expression of inflammatory molecules was measured with qPCR using SYBR green (Qiagen). Results & Discussion: The mRNA expression of inflammatory markers IL-1β, iNOS, and MCP-1 were significantly increased in HFA vs. C mice. However, dietary supplementation of blueberries significantly reduced the expression of IL-1β, iNOS, and MCP-1, indicating the beneficial effect of blueberries on the gut. The mRNA expression of IL-6 was similar among the groups. Our ongoing studies focus on identifying the molecular mechanisms involved in the protective effect of blueberries. Our study suggests consumption of blueberries may be a potential dietary approach to improve gut health.