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Pemathilaka, R. L.

Publications and source records attributed to Pemathilaka, R. L..

2 recordsLinked to original sources

Behavior of Neural Cells Post Manufacturing and After Prolonged Encapsulation within Conductive Graphene-Laden Alginate Microfibers

Engineering conductive 3D cell scaffoldings offer unique advantages towards the creation of physiologically relevant platforms with integrated real-time sensing capabilities. Toward this goal, rat dopaminergic neural cells were encapsulated into graphene-laden alginate microfibers using a microfluidic fiber fabrication approach, which is unmatched for creating continuous, highly tunable microfibers. Incorporating graphene increases the conductivity of the alginate microfibers 148%, creating a similar conductivity to native brain tissue. Graphene leads to an increase in the cross-sectional sizes and porosities of the fibers, while reducing the roughness of the fiber surface. The cell encapsulation procedure has an efficiency rate of 50%, and of those cells, approximately 30% remain for the entire 6-day observation period. To understand how encapsulation effects cell genetics, the genes IL-1{beta}, TH, TNF-, and TUBB-3 are analyzed, both after manufacturing and after encapsulation for six days. The manufacturing process and combination with alginate leads to an upregulation of TH, and the introduction of graphene further increases its levels; however, the inverse trend is true of TUBB-3. Long-term encapsulation shows continued upregulation of TH and of TNF-, and six-day exposure to graphene leads to the upregulation of TUBB-3 and IL-1{beta}, which indicates increased inflammation.

bioengineering

Maternally administered naltrexone and its major active metabolite 6β-naltrexol transport across the placental barrier in vitro

Opioid use disorder (OUD) has become a growing concern in the U.S. and has been a dominant presence among pregnant women, resulting in an unprecedented amount of prescription medications, particularly naltrexone (NTX), prescribed for pregnant women. Because of unknown potential harm that NTX can impose on the fetus and its premature brain, the needs for safety and regulation of NTX are still undetermined. To address this issue, a microfluidic device is fabricated to mimic structural phenotypes and physiological characteristic of an in vivo placental barrier to evaluate near-transport simulations of NTX and its primary metabolite, 6{beta}-naltrexol, across the placental barrier. Following transport analysis, cell layers are evaluated for possible gene-expressions released by an in vivo human placenta during NTX and 6{beta}-naltrexol placental exposure. When a 100 ng/mL dose of NTX and 6{beta}-naltrexol (1:1) is administered to the maternal channel, the mean fetal concentration for co-culture models exhibited ~2.5 % of NTX and ~2.2% of 6{beta}-naltrexol of the initial maternal concentration. To prototype and simulate fetal-brain exposure, perfusate from a fetal channel is directed to cultured N27 cells that are then evaluated for gene-expression.

bioengineering