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Hashemi, N. N.

Publications and source records attributed to Hashemi, N. N..

2 recordsLinked to original sources

How do neuroglial cells respond to ultrasound induced cavitation?

Reactive astrocytes are known to play a vital role in the overall response of the brain during a traumatic brain injury (TBI). Modern studies have speculated the existence of cavitation in the skull during a TBI, which has alarming potential to cause detrimental damages. Previous studies have confirmed the upregulation of various harmful genes in neurodegenerative diseases. Studying the longitudinal presence of these harmful genes in response to cavitation allows for optimized understanding and treatment methods in cavitation exposure. We seek to characterize the longitudinal genetic expression levels that astrocytes exhibit after exposure to cavitation and further elucidate the startling presence of cranial cavitation. Astrocytic expression levels of various common genes that have been documented in TBI research are our target of interest, like, TNF, IL-1{beta}, and NOS1. Results summarize specific gene trends from 1-48 hours after cavitation. Our data concludes that maximum expression is not consistently exhibited immediately after cavitation exposure, and most genes have individualized genetic trends. IL-1{beta} shows a decreasing expression over 48 hours, and TNF shows upregulation until the 6 hour time point but then begins to decrease in expression. The upregulation of NOS1 has been documented in neurodegenerative diseases, like Alzheimers and Parkinsons disease. This study has shown a consistent upregulation in NOS1 expression from 0-48 hours. These results postulate a possible linkage between cavitation damage and neurodegenerative diseases. This analysis also provides novelty in optimizing treatments for astrocytic function post-TBI and legitimizing the concern of cranial cavitation existence. These results add motivation for future studies of cavitation elimination or minimization via advanced helmet and airbag engineering.

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