MCW Research Publication Series: September 2017

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Medical College of Wisconsin

Research Publication Series:

September 2017 2

Adeleye James Afolayan, MD “Domain Mapping of Heat Shock Protein 70 Reveals That Glutamic Acid 446 and Arginine 447 Are Critical for Regulating Superoxide Dismutase 2 Function”

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John Densmore, MD, FACS, FAAP “Lung Injury Pathways: Adenosine Receptor 2B Signaling Limits Development of Ischemic Bronchiolitis Obliterans Organizing Pneumonia”

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Joni S. Williams, MD, MPH “Sex Differences in Healthcare Expenditures Among Adults with Diabetes: Evidence from the Medical Expenditure Panel Survey, 2002-2011”

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Callisia N. Clarke, MD “Implementation of a Standardized Electronic Tool Improves Compliance, Accuracy, and Efficiency of Trainee-to-Trainee Patient Care Handoffs after Complex General Surgical Oncology Procedures”

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David Gazeley, MD “Erosive Osteoarthritis: A Systematic Analysis of Definitions Used in the Literature”

All rights reserved. Contents are the property of the authors and/or journals cited.


Adeleye James Afolayan, MD Assistant Professor of Pediatrics Division of Neonatology Medical College of Wisconsin Children’s Hospital of Wisconsin Children’s Research Institute

I am a Physician Scientist with a broad research goal of improving the care of critically ill newborn infants with respiratory failure in the neonatal intensive care unit (NICU). I have broad background in endothelial biology with specific training, and expertise in the mechanisms regulating mitochondrial oxidative stress in vascular cells. Our group uses a host of cell culture, rodents and fetal lamb model systems to investigate the mechanisms underlying endothelial dysfunction and impaired adaptation of pulmonary circulation in neonatal pulmonary hypertension (PPHN). Existing evidence links oxidative stress to PPHN pathogenesis. My research is focused on understanding the mechanism that is responsible regulating mitochondrial oxidative stress so that better therapeutic targeting this disease can be developed.

“Domain Mapping of Heat Shock Protein 70 Reveals That Glutamic Acid 446 and Arginine 447 Are Critical for Regulating Superoxide Dismutase 2 Function” Journal of Biological Chemistry. 2017;292(6):2369-2378. Mitochondrial superoxide dismutase (SOD2), a member of SOD family of antioxidants, is the primary defense against oxidative damage. SOD2 is a nuclear encoded gene and thus, its product must be imported into the mitochondria. Heat shock protein 70 associates with SOD2 and maintains the antioxidant in an import-competent conformation. Despite SOD2 roles in cell survival, the posttranslational regulation of SOD2 remains poorly understood. In this publication, we used molecular, cell and in vivo models to characterize the structural basis of SOD2 association with hsp70. We showed that as newly made SOD2 emerges from cytosolic ribosomes, its binds to amino acid resides 445-450 constitute a critical sequence within the SOD2-binding interface in hsp70 required for SOD2 interactions. Glutamic acid (E446) and arginine (R447) residues in the SOD2-binding domain are critical for proper chaperone-dependent regulation of SOD2. Figure 4A. Effects of GERAMT peptides on mitochondrial O2 formation. Representative confocal microscopy images showing colocalization of SOD2 with mitochondria. ACh stimulation of PAECs induces SOD2 (green) localization to mitochondria (red). Treatment of PAECs with 10 μM GERAMT peptides reduces localization of SOD2 to the mitochondria at baseline and following ACh stimulation (n=3).

Figure 6. Determination of amino acid residue(s) in hsp70 that is/are critical for SOD2 interactions. A, scatterplots of SOD2 activity following site-directed mutagenesis of the GERAMT-binding site residues. Each amino acid in the GERAMT sequence was replaced stepwise with alanine (A) or more conservative residues, glutamine and asparagine (B). The mutated peptides were incubated individually with aliquots of cell lysates, and SOD2 activity was measured by colorimetric assays (**, p < 0.05 from HBSS-treated controls (CTL), n=4).


John Densmore, MD, FACS, FAAP Associate Professor Department of Surgery Division of Pediatric Surgery Medical College of Wisconsin

My basic science interest has been in areas that affect lung function and lung transplantation. Our lab demonstrated the deleterious effect of endotheliumderived microparticles on lung function and neutrophil activation in rodent models. We also demonstrated clearance of these microparticles from circulation using standard CVVH filters. With my scientific mentor, Elizabeth R. Jacobs, MD we have begun to investigate the roles of mitochondrial dysfunction and ischemia in a novel model of ischemia-induced bronchiolitis obliterans organizing pneumonia, an important precursor to lung allograft failure. This work has spanned rodent models and explanted human lungs utilizing an ex-vivo lung perfusion preparation.

“Lung Injury Pathways: Adenosine Receptor 2B Signaling Limits Development of Ischemic Bronchiolitis Obliterans Organizing Pneumonia” Experimental Lung Research. 2017;43(1):38-48. This work describes the protective effects of Adenosine 2B receptor signaling in mitigating ischemia-induced bronchiolitis obliterans organizing pneumonia in Sprague-Dawley, Dahl SS, and novel adenosine receptor knockout rats. The model involves intubation, selective left pulmonary artery ligation, and animal recovery. Studies were completed at 4h, 24h, and 7 days and ligated lungs were compared to their contralateral control. We found adenosine concentrations from BAL specimens increased in ischemic lungs at 24 hours. A2BAR expression was increased at 24 hours and negatively regulating miR27a was decreased, reflecting a activation of A2BAR in response to the injury. No such changes were seen with A2BAR. These changes were seen in both Dahl SS and Sprague Dawley rats. Finally, Adora2b mutants showed a much greater extent of BOOP by histologic grading as compared to the Dahl SS genetic background. Figure 6. Representative histological images from lung cross sections from SS (a and b) and M1 AdorA2BA mutant rats (c and d) seven days after ischemia. Low power (a and c) shows areas of increased cellularity, which were consistent with BOOP under high power magnification (b and d). The area of BOOP is modestly larger in the image from lungs of M1 mutant rats. The blue arrows in the magnified images (b and d) show typical epithelial changes, whereas the red arrow shows perivascular inflammation (b). In some images from M1 mutants (not shown), areas of inflammation outside sections showing significant epitheliod changes were observed.

C

A

2 mm

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200 µm

200 µm


Joni S. Williams, MD, MPH Assistant Professor Department of Medicine Division of General Internal Medicine Center for Patient Care and Outcomes Research Medical College of Wisconsin

I am an Assistant Professor of Medicine in the Division of General Internal Medicine and the Center for Patient Care and Outcomes Research (PCOR). A native of South Carolina, I attended the University of South Carolina, where I earned a Bachelor of Science in Biology. Shortly thereafter, I attended Drexel University and earned a Master of Public Health with a concentration in Community Health and Prevention. After graduating from the Medical University of South Carolina (MUSC) School of Medicine, I completed a Postdoctoral Fellowship in Health Disparities within the Division of General Internal Medicine and Geriatrics and the Center for Health Disparities Research at MUSC. My research specialties are health disparities and patient-oriented outcomes focused on intervention development to improve outcomes in minority women with chronic diseases.

“Sex Differences in Healthcare Expenditures Among Adults with Diabetes: Evidence from the Medical Expenditure Panel Survey, 2002-2011” BMC Health Services Research. 2017;17(1):259. Evidence assessing differences in medical costs between men and women with diabetes is limited, but suggests women generally have higher healthcare expenditures compared to men. Data were used from 20,442 adults (≥18 years of age) with diabetes from the Medical Expenditure Panel Survey to assess differences in out-of-pocket (OOP) and total healthcare expenditures. After adjusting for covariates, women had higher OOP and total direct costs for prescription services (OOP: $156; 95% CI $87-$225; p<0.001 and total: $184; 95% CI $50-$318; p=0.007) and paid >$50 in OOP and total expenditures for both office-based visits (p<0.001) and home healthcare (p=0.041) compared to men. Our findings show women with diabetes have higher OOP and total direct expenditures compared to men. Additional research is needed to assess the underlying causes and clinical implications associated with this disparity and to inform policies that minimize the higher cost burden for women with diabetes.

Table 3: Two-part regression model-Incremental effects of healthcare expenditures by sex among adults with diabetes Variables

Incremental Cost

95% Confidence Interval

P-value

Out-of-pocket expenses Prescription Office-Based Inpatient Outpatient ER visit Dental Home healthcare Others Pooled

156 53 -0.36 12 -3 19 9 19 242

87–225 24–83 -21–20 1.5–23 -8–2 -7–46 -1–20 7–30 134–350

<0.001*** <0.001*** 0.972 0.026* 0.285 0.156 0.080 0.001** <0.001***

Total direct expenditures Prescription Office-Based Inpatient Outpatient ER visit Dental Home healthcare Others Pooled

184 2 -213 45 -23 25 59 -0.86 232

50–318 -153–158 -563–136 -73–165 -58–11 -17–68 2–116 -21–20 -300–765

0.007** 0.975 0.232 0.454 0.180 0.245 0.041* 0.936 0.392

Reported as dollars in 2014. *Level of significance p< 0.05; ** level of significance p<0.01, ***level of significance p < 0.001. Reference group: men with diabetes. Primary outcome variables in this regression model are out-of-pocket and total direct expenditures controlling for age, sex, race/ethnicity, marital status, education, health insurance, MSA, census region, income, comorbid conditions (hypertension, CVD, stroke, emphysema, joint pain, arthritis, and asthma) and time trend.


Callisia N. Clarke, MD Assistant Professor of Surgery Division of Surgical Oncology Medical College of Wisconsin

I am an Assistant Professor of Surgery in the Division of Surgical Oncology here at MCW. I attended medical school and completed my residency at the University of Cincinnati College of Medicine. I also studied under a fellowship in Complex General Surgical Oncology at the University of Texas MD Anderson Cancer Center. Clinically, I specialize in surgical oncology with a focus on tumors of the upper gastrointestinal tract, sarcomas, melanomas and regional therapies for advanced malignancies. My research interests are centered on personalized cancer care and targeted approaches in oncology.

“Implementation of a Standardized Electronic Tool Improves Compliance, Accuracy, and Efficiency of Trainee-to-Trainee Patient Care Handoffs after Complex General Surgical Oncology Procedures” Surgery. 2017;161(3):869-875. 1 In the study we recently published, we looked into how dosing and drug levels affect response to therapy of fistulas in patients with Crohn’s disease. Unfortunately, many patients with Crohn’s develop fistulas from the intestine to either other internal organs or the skin. This can dramatically affect the quality of life of patients and lead to complications requiring surgery. Fistulas are also very hard to treat. While infliximab (a monoclonal antibody that targets tumor necrosis factor) has been useful in the treatment of Crohn’s disease and fistulas, many patients do not respond to treatment. In this study, we found that a significant amount of patients need higher doses of infliximab and achieve higher serum levels of the drug in order to respond. Until now, many physicians would discontinue infliximab if there was no response to the standard doses. However, after this study, we know that we can induce remission in many of the patients that do not respond by optimizing the drug.

Figure 2. Process mapping demonstrated a circular process starting with the sender (outgoing trainee) handing off to the receiver (on-call trainee). Analysis revealed wide variation in compliance of the trainee handoffs and content, because this nonstructured method of handoff resulted in communication inconsistencies. Several areas were noted to be heavily subjective and are highlighted in the shaded box. These areas were also associated with poor trainee workflow and overall inefficiency.

Figure 3. Implementation of a structured electronic tool resulted in significant improvements of all measured, postintervention outcome metrics. HO, Hand off; POC, post operative check.


David Gazeley, MD Assistant Professor Department of Medicine Division of Rheumatology Medical College of Wisconsin

I joined MCW in 2014 as an Assistant Professor of Medicine. I attended the University of Wisconsin School of Medicine and Public Health graduating in 2006 and completed a medicine residency at Tufts Medical Center in 2009. Following a rheumatology fellowship at MCW, I joined the faculty at UW in 2011 until returning to MCW in 2014. I practice general rheumatology and see patients at both Froedtert Clinics and Westbrook Health Center. I work closely with fellows staffing a weekly clinic and regularly work with other medical learners. Although the majority of my time is spent in the clinic, I felt a systematic review exploring the definition of this poorly described entity called erosive osteoarthritis was needed.

“Erosive Osteoarthritis: A Systematic Analysis of Definitions Used in the Literature� Seminars in Arthritis and Rheumatism. 2017;46(4):395-403. The clinical syndrome known as erosive osteoarthritis (EOA) represents a challenging type of hand osteoarthritis. The epidemiology and clinical symptoms differ from typical hand OA and management strategies are poorly defined and untested. In reviewing the EOA literature, we noted considerable variation in the disease definition. We undertook a systematic review with an objective of assessing the variability of published definitions of EOA. We performed a literature search and 62 studies met our inclusion criteria that included a stated definition of EOA. This systematic review found little uniformity among studies regarding a definition of EOA. The majority (60%) of studies utilized the 1990 ACR hand OA definition though six studies used no clinical definitions and 30% of studies included no exclusion criteria to eliminate EOA mimics. Nearly all studies used a radiographic definition though these varied widely and the majority of authors used their own unique radiographic definitions of EOA. Lack of diagnostic consensus on EOA seriously weakens the impact of clinical studies of therapies for this painful osteoarthritis.

An example of hand radiograph often described as erosive osteoarthritis though, as discovered in our review, radiographic definitions vary widely.



Medical College of Wisconsin Office of Research 8701 W Watertown Plank Road Milwaukee, WI 53226-0509 mcw.edu/office-of-research.htm


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