Global Health Colloquium

Student Presentations:  Amy Klegarth (Hollocher Lab), Julia Kohn (Hollocher Lab), and Ling Sun (Sucosky Lab)

Julia Kohn (Hollocher Lab) - Genetic population structure in long-tailed macaques (Macaca fascicularis) across Singapore
Julia Kohn is a senior Biological Sciences major at the University of Notre Dame. Her research examines the dynamics of population genetics in macaque monkeys in Singapore. She is hoping to pursue careers in global health or medicine after graduation.
Abstract - Understanding the effects of different anthropogenic landscapes on the population structure of any species allows researchers to examine the impact of landscape changes on gene flow. The long-tailed macaque (Macaca fascicularis) is native to Singapore, a small island city in Southeast Asia. The highly urbanized nature of the city has fragmented forest patches and may affect gene flow between different groups of macaques on the island. Preliminary results from a maximum-likelihood tree indicate that there is no population structure in Singapore’s macaques. Multiple haplotypes appear in the sequence data, some of which represent individuals from multiple sites across the island. This may reflect Singapore’s ecological history, as the island was completely forested with no anthropogenic barriers to gene flow until 1819; it may also reflect macaques’ ability to successfully navigate the urban environment.
Amy Klegarth (Hollocher Lab) - Monkey Management: Using Landscape Genetics & Technology To Inform Management

Bio: I'm a third year graduate student in the Hollocher Lab working with Hope Hollocher and Agustin Fuentes on their collaborative macaque project based in Singapore. My work's primary focus is on Singapore macaques with some comparisons to Balinese macaque populations. I'm a GLOBES fellow, and as such my work has a heavy application, management, and outreach component.

Abstract: Long-tailed macaques are part of the 2nd largest primate radiation trailing only humans. They heavily interface with human populations, especially in the densely populated regions of Southeast Asia. This interface provides opportunities for human-wildlife conflict and even potential parasite sharing. In order to manage conflict and understand disease dynamics my work explores the landscape genetic patterns influencing the macaques. Landscape genetic analyses are complemented by the implementation of technology-based monitoring such as range assessment via GPS satellite collars and behavioral assessments via video-collar monitoring. Here I report on preliminary ranging and genetic data as well as the future analyses that will be carried out.

Ling Sun (Sucosky Lab) - Role of Side-Specific Shear Stress Alterations in Calcific Aortic Valve Disease Pathogenesis
Biosketch: Ling Sun received her B.S. in Biomedical Engineering in 2009 in Zhejiang University, China. She joined the Multi-Scale Cardiovascular Bioengineering Laboratory directed by Dr. Philippe Sucosky in 2009 and is currently investigating the role played by hemodynamics on heart valve pathobiology.
Abstract: Calcific aortic valve disease (CAVD), the most common heart valve disease, follows an active process involving inflammation, ECM remodeling and ossification. Although the disease mechanisms remain largely unknown, studies increasingly suggest that CAVD could result from the presence of abnormal fluid shear stress on the leaflets. The porcine leaflets were exposed to different magnitudes of side-specific shear stress in a novel double cone-and-plate bioreactor.  Endothelial activation was investigated via immunohistochemistry in terms of ICAM-1 and VCAM-1 expressions. Tissue inflammation was examined in terms of pro-inflammatory cytokines (TGF-β and BMP-4). ECM remodeling was characterized in terms of collagenase and proteases (MMPs and Cathepsins). The results demonstrate the supra-physiological magnitude of shear stress activates valvular inflammation and remodeling. This study provides new insights into CAVD pathogenesis.