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Item The effect of increasing power when grooving using phacoemulsification(2019) Thomson, Rhett S.; Bird, Brian A.; Stutz, Lance A.; Heczko, Joshua B.; Bernhisel, Ashlie A.; Barlow, William R.; Zaugg, Brian; Olson, Randall J.; Pettey, Jeff H.To determine optimal power settings on the Centurion Vision System during the grooving step in cataract surgery. Methods: Intact porcine lenses hardened by formalin and placed in a chamber designed to simulate the anterior chamber of the eye were used to test longitudinal power at 40%, 70%, and 100% and torsional power at 0%. Flow rate was set at 40 mL/min. Vacuum was set at 400 mmHg, intraocular pressure was set at 50 mmHg, and a balanced phacoemulsification tip with a 20 degree tip and a 30 degree bevel was used. Efficiency (time to groove the lens in half) was determined. Results: Increasing longitudinal power from 40% to 70% increased efficiency by 28% (P< 0.05), and by 32% (P<0.05) when increasing longitudinal power from 40% to 100%. There was no statistically significant increase in efficiency from 70% to 100%. Conclusion: For the tested variables, a longitudinal power of 70% was determined to be most efficient during the grooving step of cataract surgery for equivalent 3-4+ nuclei. Further increases in power demonstrated no statistically significant improvement in efficiency.Item Prevalence of Nasal Colonization by Methicillin-Resistant Staphylococcus aureus in Persons Using a Homeless Shelter in Kansas City(2016) Ottomeyer, Megan; Graham, Charles D.; Legg, Avery D.; Cooper, Elizabeth S.; Law, Chad D.; Molani, Mariam; Matevossian, Karine; Marlin, Jerry; Williams, Charlott; Newman, Ramon; Wasserman, Jason A.; Segars, Larry W.; Taylor, Tracey A. H.Nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA) plays an important role in the epidemiology and pathogenesis of disease. Situations of close-quarter contact in groups are generally regarded as a risk factor for community-acquired MRSA strains due to transmission via fomites and person-to-person contact. With these criteria for risk, homeless individuals using shelter facilities, including showers and toilets, should be considered high risk for colonization and infection. The aim of this study was to determine the prevalence of nasal colonization of MRSA in a homeless population compared to established rates of colonization within the public and a control group of subjects from a neighboring medical school campus, and to analyze phylogenetic diversity among the MRSA strains. Nasal samples were taken from the study population of 332 adult participants and analyzed. In addition, participants were surveyed about various lifestyle factors in order to elucidate potential patterns of behavior associated with MRSA colonization. Homeless and control groups both had higher prevalence of MRSA (9.8 and 10.6%, respectively), when compared to the general population reported by previous studies (1.8%). However, the control group had a similar MRSA rate compared to health-care workers (4.6%), while the homeless population had an increased prevalence. Risk factors identified in this study included male gender, age over 50 years, and use of antibiotics within the past 3 months. Phylogenetic relationships between nine of the positive samples from the homeless population were analyzed, showing eight of the nine samples had a high degree of relatedness between the spaA genes of the MRSA strains. This indicates that the same MRSA strain might be transmitted from person-to-person among homeless population. These findings increase our understanding of key differences in MRSA characteristics within homeless populations, as well as risks for MRSA associated with being homeless, such as age and gender, which may then be a useful tool in guiding more effective prevention, treatment, and health care for homeless individuals.Item A Rare Presentation of Drug-induced Liver Injury with Fluticasone and Vilanterol Inhaler Use(2019) Rishi, Mohit; Wagner, Amanda; Ulanja, Mark B.; Beutler, Bryce D.; Singh, KarmjitDrug-induced liver injury (DILI) is a rare and potentially lethal condition associated with the use of many commonly-used medications, including inhaled fluticasone-vilanterol. Therefore, a careful review of medications should always be obtained in the setting of acute onset hepatic dysfunction. We present the first reported case of idiosyncratic drug-induced liver injury associated with the use of this medication.Item Generation of electrophysiologically functional cardiomyocytes from mouse induced pluripotent stem cells(2016) Wang, Hongran; Xi, Yutao; Zheng, Yi; Wang, Xiaohong; Cooney, Austin J.Induced pluripotent stem (iPS) cells can efficiently differentiate into the three germ layers similar to those formed by differentiated embryonic stem(ES) cells. This provides a new source of cells in which to establish preclinical allogeneic transplantation models. Our iPS cells were generated from mouse embryonic fibroblasts (MEFs) transfected with the Yamanaka factors, the four transcription factors (Oct4, Sox2, Klf4 and c-Myc), without antibiotic selection or MEF feeders. After the formation of embryoid bodies (EBs), iPS cells spontaneously differentiated into Flk1-positive cardiac progenitors and cardiomyocytes expressing cardiac-specific markers such as alpha sarcomeric actinin (alpha-actinin), cardiac alpha myosin heavy chain (alpha-MHC), cardiac troponin T (cTnT), and connexin 43 (CX43), as well as cardiac transcription factors Nk2 homebox 5 (Nkx2.5) and gata binding protein 4 (gata4). The electrophysiological activity of iPS cell-derived cardiomyocytes (iPS-CMs) was detected in beating cell clusters with optical mapping and RH237 a voltage-sensitive dye, and in single contracting cells with patch-clamp technology. Incompletely differentiated iPS cells formed teratomas when transplanted into a severe combined immunodeficiency (SCID) mouse model of myocardial infarction. Our results show that somatic cells can be reprogrammed into pluripotent stem cells, which in turn spontaneously differentiate into electrophysiologically functional mature cardiomyocytes expressing cardiac-specific makers, and that these cells can potentially be used to repair myocardial infarction (MI) in the future. (C) 2016 University of Texas at Austin Dell Medical School. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Item Gastric and Duodenal Pseudomelanosis: An Extended Unusual Finding in a Patient with End Stage Kidney Disease(2016) Qureshi, Noor U. A.; Younus, Muhammad F.; Alavi, Kourosh; Sheikh, Muhammad Y.Gastric and duodenal pseudomelanosis is a rare endoscopic mucosal finding, characterized by the accumulation of iron in macrophages of the lamina propria of the stomach and duodenum. The clinical significance and long term sequelae have not been clarified yet. However, this benign condition is associated with a variety of clinical conditions, such as essential hypertension, chronic renal failure, diabetes mellitus, long term intake of iron supplements, and furosemide. Duodenal pseudomelanosis appears to be more common than gastric pseudomelanosis given the fact that a few cases of gastric pseudomelanosis have been reported in the literature so far. We report a case of 88-year-old lady with ESRD who is maintained on hemodialysis and presented with abdominal pain. An upper GI endoscopy showed discoloration of the antrum of the stomach and most portion of her duodenum. Histopathology report confirmed the presence of iron laden macrophages in the lamina propria of both stomach and duodenum.