Mary Osbakken

Dr. Osbakken graduated from the University of Illinois with her undergraduate degree and Master’s degree in Physiology before coming to Jefferson to complete a PhD in Physiology. After graduating in 1969 she began teaching at Beaver College (now Arcadia University) and concurrently pursuing a Master’s in Biomedical Engineering from Drexel University. She then went on to earn an M.D. from Temple University Medical School. Dr. Osbakken completed her internship at Pennsylvania Hospital before taking fellowships in Cardiology and Nuclear Magnetic Resonance at Temple University Medical School, University of Pennsylvania Medical School, and Massachusetts General Hospital. After her fellowships she worked at Hershey Medical Center and later at University of Pennsylvania. Dr. Osbakken then entered the biotech and pharmaceutical fields working at Bristol-Myer-Squibb, Covance, Sanofi-Aventis, and Inotek. She currently runs her own consulting firm working with biotechs, startups, and pharmaceutical companies

Gendered Intersections: Negotiating Power, Status, and Identity in Interdisciplinary Science.

Interdisciplinary solutions are increasingly touted as essential to solve intractable problems in health research, but recent studies have shown that perceptions of scientific status shape how science is negotiated in interdisciplinary groups, threatening the potential of these boundary-breaking mergers. To date, however, existing studies focus exclusively on epistemological differences, failing to consider how other dimensions of difference and inequality shape the process and products of interdisciplinary science. Gender as an analytic category and marker of difference, for example, is all but ignored in this canon, even though a parallel research program demonstrates the multiple barriers women face in the sciences. This project seeks to fill this gap and bridge these two research areas. This qualitative study draws from over 90 hours of ethnographic observation and 23 semi-structured qualitative interviews to inductively explore how nurses, engineers, and doctors, working together in an interdisciplinary group in the academic health sciences, negotiate gender and other differences as they collaborate on a shared problem in women’s health. I show that the nurses felt marginalized in the group from the beginning as they faced multiple structural and cultural obstacles to equality. Intersecting status markers, many of which were gendered, shaped their experiences in the group, and ultimately the process and products of the group’s collaboration. Finally, I highlight the identity processes involved in interdisciplinary collaboration, showing how the nurses adopted various strategies to manage their experiences of inequality in the group, strategies that often and ironically exacerbated their unequal position. This research highlights the importance of considering power and status differences, and especially the effects of gender, in interdisciplinary collaborations in the sciences. Some individuals, especially those who suffer from multiple, intersecting low-status markers, may face particular risks in interdisciplinary research groups. Moreover, this project reveals that even successful groups can unconsciously privilege certain perspectives and scientific approaches, thereby limiting the potential of interdisciplinary collaborations.PHDSociologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/108804/1/osbakken_1.pd

The Role of Sodium in Diabetic Cardiomyopathy

Cardiovascular complications are the major cause of mortality and morbidity in diabetic patients. The changes in myocardial structure and function associated with diabetes are collectively called diabetic cardiomyopathy. Numerous molecular mechanisms have been proposed that could contribute to the development of diabetic cardiomyopathy and have been studied in various animal models of type 1 or type 2 diabetes. The current review focuses on the role of sodium (Na+) in diabetic cardiomyopathy and provides unique data on the linkage between Na+ flux and energy metabolism, studied with non-invasive 23Na, and 31P-NMR spectroscopy, polarography, and mass spectroscopy. 23Na NMR studies allow determination of the intracellular and extracellular Na+ pools by splitting the total Na+ peak into two resonances after the addition of a shift reagent to the perfusate. Using this technology, we found that intracellular Na+ is approximately two times higher in diabetic cardiomyocytes than in control possibly due to combined changes in the activity of Na+–K+ pump, Na+/H+ exchanger 1 (NHE1) and Na+-glucose cotransporter. We hypothesized that the increase in Na+ activates the mitochondrial membrane Na+/Ca2+ exchanger, which leads to a loss of intramitochondrial Ca2+, with a subsequent alteration in mitochondrial bioenergetics and function. Using isolated mitochondria, we showed that the addition of Na+ (1–10 mM) led to a dose-dependent decrease in oxidative phosphorylation and that this effect was reversed by providing extramitochondrial Ca2+ or by inhibiting the mitochondrial Na+/Ca2+ exchanger with diltiazem. Similar experiments with 31P-NMR in isolated superfused mitochondria embedded in agarose beads showed that Na+ (3–30 mM) led to significantly decreased ATP levels and that this effect was stronger in diabetic rats. These data suggest that in diabetic cardiomyocytes, increased Na+ leads to abnormalities in oxidative phosphorylation and a subsequent decrease in ATP levels. In support of these data, using 31P-NMR, we showed that the baseline β-ATP and phosphocreatine (PCr) were lower in diabetic cardiomyocytes than in control, suggesting that diabetic cardiomyocytes have depressed bioenergetic function. Thus, both altered intracellular Na+ levels and bioenergetics and their interactions may significantly contribute to the pathology of diabetic cardiomyopathy

Use of DES-treated rats as an animal model for assessment of pituitary adenoma imaging agents

Prolactin (PRL) secreting pituitary adenomas are the most common type of pituitary tumors. An imaging agent which specifically localized in prolactinomas would be of considerable clinical value for both initial detection and also for monitoring the effects of dopamine agonist therapy. Tritiated spiroperidol (3HSp) was selected for initial evaluation as a possible imaging agent based on: (1) demonstrated localization in the pituitary and (2) demonstrated binding to human PRL-secreting tumor tissue. DES was implanted in Fischer F344 rats and induced prolactinoma formation was evidenced by increased pituitary weight, elevated serum PRL levels and by an increase in the proportion of PRL-secreting cells in the pituitary. 3HSp concentrations in pituitary and other tissues of DES-treated rats were assessed in female rats and correlation studies showed that a 5-fold increase in serum PRL was associated with a 6-fold increase in both pituitary weight and % dose/organ accumulation of 3HSp. The number of pituitary D2 receptors per mg of protein in tissue homogenates was similar in both normal and DES-treated females. A blocking study with (+)-butaclamol demonstrated a D2 receptor-mediated component to 3HSp localization. In summary, an animal model for prolactinoma was characterized. An assessment of 3HSp accumulation indicates that radiolabelled spiroperidol shows excellent potential for detecting PRL-secreting tumors of the pituitary.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26426/1/0000514.pd

Cardiovascular monitoring during elective aortic surgery.

We designed a prospective study to determine whether cardiac ejection fraction as measured noninvasively could isolate a subset undergoing aortic surgery for whom central venous pressure (CVP) predicted pulmonary artery wedge pressure (PAWP). Sixteen patients were studied. Simultaneous values of PAWP and CVP were analyzed, using linear regression analysis. A significant correlation between CVP and PAWP was found for the entire patient population and for each of four time periods: preoperative, before and after aortic cross-clamping, during aortic cross-clamping, and postoperative. A significant correlation between PAWP and CVP was found during the entire perioperative period for 14 of the 16 patients. However, the slope of the regression line, or the sensitivity of the CVP in reflecting changes in PAWP, was greater than 0.5 in only seven of the 16 patients. There was no correlation between the preoperative ejection fraction and the CVP/PAWP. We conclude that the CVP is an insensitive indicator of left ventricular filling pressure in most patients accepted for elective infrarenal aortic surgery, and monitoring of the PAWP is recommended