First FSSHH of this year at Homewood!!

Come enjoy the friendly welcome from Homewood at this upcoming FSSHH!

Jake is presenting with food volunteered by Sravanti.

Who: Jake Simson

When: September 17th

Where: Clark 110 Homewood

See you all there!

Title: The application of a chondroitin sulfate-bone marrow adhesive towards

meniscal repair

Abstract: Meniscal injuries may lead to joint degeneration and the development of post-traumatic osteoarthritis. There are few technologies beyond sutures available for surgeons to repair the meniscus, and sutures inherently cause additional damage to the tissue. Adhesives that work to repair meniscus while fixing the tissue in place offer an appealing alternative solution. Here, we demonstrate the use of a NHS-functionalized chondroitin sulfate (CS-NHS) bioadhesive for use in meniscal repair. 10% CS-NHS was mixed with 10% Polyethylene Glycol (PEG) in a 1:1 ratio, and with BM in ratios of 3:7 (70% BM), 1:1 (50% BM), and 7:3 (30% BM). Meniscus cells were encapsulated in gels to quantify in vitro tissue generation, and bovine meniscus explants were glued to observe meniscus cell migration into the adhesive. Constructs were analyzed at one and three weeks using live/dead, H&E staining, and Hoescht dye DNA assays. Glued tissue explants were sectioned and stained with H&E at two and four weeks. Live/dead and Hoescht DNA assays showed statistically significantly higher viability at both time points in CS-BM gels in comparison to CS-PEG. At one week normalized DNA levels increased with BM concentration, but this effect diminished by week three. However, extensive clustering of cells was observed at three weeks in CS-BM gels, indicating cell proliferation. In the explant study cells were observed proliferating on the surface of 70% BM at week two, and at week four cells were seen within the gel proliferating and depositing matrix. These findings indicate that meniscal cell viability in the CS-BM gel remains high after several weeks in culture, they proliferate within the gel, and that meniscal cells are capable of migrating from meniscal tissue first onto the hydrogel surface, and later into BM gels. These are promising preliminary results for the use of CS-BM adhesive in regenerating meniscus tissue.

FSSHH this Friday!

Come to the first FSSHH (Friday Student Seminar and Happy Hour) of the year!

Food and drink and fun; plus learn about the cool work of one of your fellow grad students.

WHO: Matt Fifer, a second year student from Dr. Thakor's lab is giving the talk

WHAT: Decoding grasp kinematics from human electrocorticography (ECoG)

WHERE: Traylor 709

WHEN: 5pm Friday August 27th.

Title:

Decoding grasp kinematics from human electrocorticography (ECoG)

Abstract:

Human electrocorticography (ECoG) is a neural recording modality used for seizure localization in epileptic patients prior to resection surgery. We measured ECoG amplitude in 4 subjects and attempted to predict the degree of grasp aperture during a slow grasping motion of the hand. Decoding accuracy was found to be high (mean r > 0.6), to be relatively invariant to wrist rotation angle, and to require relatively few electrodes to achieve maximal performance. This work is promising for the potential future development of a reliable, low-footprint ECoG-driven neuroprosthetic. Future work is targeting the application of similar methods to more natural reach-to-grasp motions.

FSSHH: Friday April 2 5pm Traylor 709 Med Campus

Presenter: Susan Thompson

Title: Human Embryonic Stem Cell Derived Cardiomyocytes Ameliorate Vulnerability for Arrhythmias in an In Vitro Model of Cardiac Fibrosis

Abstract: Human embryonic stem cells (hESCs) are an attractive candidate for cardiac regeneration because of their potential to supply a large number of differentiated cardiomyocytes that can integrate into the host tissue, thereby replacing the myocytes lost during myocardial aging, disease or damage. Numerous studies have already demonstrated improved myocardial function with grafts of human embryonic stem cell-derived cardiomyocytes (hESC-CMs), alluding to possible roles of paracrine effects and direct myocardial regeneration. However, little attention has been given to the electrophysiological benefit that these cells may have on diseased myocardium, and specifically, on cardiac fibrosis, a pathological condition found in aging, heart failure, and myocardial infarction. We therefore set out to characterize the electrophysiological benefits of adding hESC-CMs to our previously reported, in vitro model of cardiac fibrosis. Following engraftment of hESC-CMs from beating hESC-CMs, LCV and TCV of fibrotic monolayers increased to 39.3±2.7 and 12.5±1.3 cm/s, respectively (n=6). In contrast, addition of hESCs from non-beating EBs suppressed LCV and TCV to 6.5±1.3 and 2.1±1 cm/s, respectively (n=4). We show for the first time that hESC-CMs reverse the loss of conduction velocity and reduce the incidence of spiral waves in an in vitro fibrosis model. This finding is significant in that it suggests that specifically hESC-CMs can directly participate in electrical propagation, perhaps through gap junction coupling, and can ameliorate abnormal conduction in fibrotic myocardium.