Search

Your search keyword '"Stark, Terra"' showing total 15 results
Start Over Author "Stark, Terra"
15 results on '"Stark, Terra"'

9. Dysregulated energy metabolism impairs chondrocyte function in osteoarthritis.

Author

Wu, X., Liyanage, C., Plan, M., Stark, T., McCubbin, T., Barrero, R.A., Batra, J., Crawford, R., Xiao, Y., Prasadam, I., Wu, Xiaoxin, Liyanage, Chamikara, Plan, Manuel, Stark, Terra, McCubbin, Tim, Barrero, Roberto A, Batra, Jyotsna, Crawford, Ross, Xiao, Yin, and Prasadam, Indira

Abstract

Objectives: Metabolic pathways are a series of chemical reactions by which cells take in nutrient substrates for energy and building blocks needed to maintain critical cellular processes. Details of chondrocyte metabolism and how it rewires during the progression of osteoarthritis (OA) are unknown. This research aims to identify what changes in the energy metabolic state occur in OA cartilage.Methods: Patient matched OA and non-OA cartilage specimens were harvested from total knee replacement patients. Cartilage was first collected for metabolomics, proteomics, and transcriptomics analyses to study global alterations in OA metabolism. We then determined the metabolic routes by tracking [U-13C] isotope with liquid chromatography-mass spectrometry (LC-MS). We further evaluated cellular bioenergetic profiles by measuring oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) and investigated the effects of low-dose and short-term effects of 2-deoxyglucose (2DG) on chondrocytes.Results: OA chondrocytes showed increased basal ECAR and more lactate production compared to non-OA chondrocytes. [U-13C] glucose labelling revealed that less glucose-derived carbon entered the tricarboxylic acid (TCA) cycle. On the other hand, mitochondrial respiratory rates were markedly decreased in the OA chondrocytes compared to non-OA chondrocytes. These changes were accompanied by decreased cellular ATP production, mitochondrial membrane potential and disrupted mitochondrial morphology. We further demonstrated in vitro that short-term inhibition of glycolysis suppressed matrix degeneration gene expression in chondrocytes and bovine cartilage explants cultured under inflammatory conditions.Conclusion: This study represents the first comprehensive comparative analysis of metabolism in OA chondrocytes and lays the groundwork for therapeutic targeting of metabolism in OA. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

12. Hybridization of ZSM-5 with spinel oxides for biomass vapour upgrading

Author

Atanda, Luqman, Batalha, Nuno, Stark, Terra, Tabulo, Ben, Perkins, Greg, Wang, Zhiliang, Odedairo, Taiwo, Wang, Lianzhou, Konarova, Muxina, Atanda, Luqman, Batalha, Nuno, Stark, Terra, Tabulo, Ben, Perkins, Greg, Wang, Zhiliang, Odedairo, Taiwo, Wang, Lianzhou, and Konarova, Muxina

Abstract

In this study, we report catalytic fast pyrolysis of biomass using multifunctional hybrid spinel-oxide@zeolite catalysts prepared by using the steam-assisted crystallization (SAC) method to create the mesoporous zeolite followed by urea hydrolysis of metal nitrates to deposit spinel-oxides. This hybrid catalyst was quite effective in the deoxygenation of pinewood sawdust pyrolysis vapours, while avoiding over cracking of the lignin precursors, which are already ideal as chemical and fuel precursors. In the first step, multiple spinel oxides MgB2O4 (where B=Fe, Al, Ce, Ga, Cr) were screened as catalysts for the pyrolysis of pinewood sawdust and the resultant bio-oil (bio-oil on the water-free basis) was assessed in terms of carbon efficiency, oxygen content and chemical composition. While all the tested spinel oxides deoxygenated the pyrolysis vapour, MgAl2O4 and MgFe2O4 were found to provide a well-balanced deoxygenation degree and producing bio-oil with acceptable carbon efficiency. Catalytic activity and product distribution were affected by the density and strength of the acid sites of the spinel oxides. Subsequently, CFP over MgFe2O4@ZSM5 and MgAl2O4@ZSM5 was investigated under similar condition. The better performance of the hybrid catalyst was attributed to the deposition of small particles of MgFe2O4 in the external surface of the zeolite. The presence of this spinel oxide on the external surface depolymerized bulky oxygenates to lighter fractions that could easily access the active sites within the mesoporous structure of the zeolite, thus providing the catalytic function needed for the oxygen removal after aromatic ring saturation.

Published
2020

15. Terra Firma: Finding Solid Ground for Migrant Children and Families.

Author

Shapiro A, Stark B, and de la Peña CM

Subjects
Humans, Child, United States, Transients and Migrants
Abstract

Competing Interests: Declaration of Competing Interest None of the authors have any conflicts of interest and the work has no corporate sponsors. This article was published as part of a supplement sponsored by the Robert Wood Johnson Foundation.

Published
2024
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results