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Item Generation and Exploration of a Novel Low Oxygen Landscape for Hematopoietic Stem and Progenitor Cells(2022-10) Dausinas, Paige Burke; Elmendorf, Jeffrey; O'Leary, Heather; Bidwell, Joseph; Wan, Jun; Zhang, JiHematopoietic stem (HSC) and progenitor (HSPC) cells reside in low oxygen (~1- 4%, low O2) bone marrow niches which provide critical signals for maintenance, selfrenewal, and differentiation. Exposure of HSC/HSPCs to air (~21%) for less than 10 minutes irreversibly diminishes numbers of phenotypic and functional stem cells, a phenomenon termed extra physiologic oxygen stress/shock. Yet, most studies harvest and analyze HSC/HSPCs in air and often in fixed cells, leaving endogenous signaling mechanisms unidentified. To better understand the endogenous mechanisms regulating HSCs and HSPCs, we generated the first low O2 landscape of phenotypic/functional/signaling alterations in live, low O2 harvested/sorted HSC/HSPCs utilizing novel technology. HSC (LSKCD150+) and HSC/HSPC (LSK) expression, frequency, and stem cell maintenance retention were enhanced in low O2 relative to historic data and our air data. Transcriptomics uncovered low O2 differential pathway regulation of HSC/HSPCs and HSCs with analysis identifying low O2 enrichment of genes/pathways including Ca2+ ion binding, altered sodium hydrogen (Na+/H+) activity, viral entry, and transmembrane receptor activity in both HSCs and HSPCs. In exploring the low O2 landscape, we investigated differential low O2 regulation of Ca2+ and SARS-CoV-2 related pathways/mechanisms in HSCs and HSPCs. Differential Ca2+ regulation was observed in our transcriptional/proteomic analysis corroborated by phenotypic/functional data demonstrating increases in low O2 of cytosolic and mitochondrial Ca2+ flux, ABC Transporter (ABCG2) and Na+/H+ (NHE1) expression, discovery of a novel low O2 Ca2+ high HSPC population that enhances HSC maintenance compared to Ca2+ low populations and blunting of this population and subsequent enhanced stem cell maintenance upon NHE1 inhibition (Cariporide). Multi-omics analyses also identified enhancements in COVID19-related pathways in low O2 that corresponded with enhanced expression of SARS-CoV-2 receptors/co-receptors, SARS-CoV-2 spike protein (SP) binding, and expansion of SP-bound HSC/HSPCs in low O2 compared to air, as well as enhanced stem cell maintenance of SP-bound, versus unbound, cells in low O2. Together, these data presented show low O2 harvest/retention of HSC/HSPCs enhances stem cell maintenance, which could be utilized to improve HSC expansion, and leads to differential pathway/signaling regulation of various biological pathways in HSC/HSPCs including Ca2+ and SARS-CoV-2/viral infection that results in phenotypic and functional consequences.Item Implementation of solar powered oxygen delivery in a conflict zone: Preliminary findings from Somalia on feasibility and usefulness(T&F, 2022-06-22) Mian, Qaasim; Rahman Malik, Sk Md Mamunur; Alinor, Mohamed Adam; Hossain, Md Shajib; Sharma, Jitendar Kumar; Hassan, Osman Moallim; Ahmed, Abdiwali Mohamed; Jama, Abdiweli Abdullahi; Okello, Andrew J.; Namasopo, Sophie; Opoka, Robert O.; Conradi, Nicholas; Abdullah, Saleh; Conroy, Andrea L.; Hawkes, Michael T.; Pediatrics, School of MedicineAccess to therapeutic oxygen in low-resource settings remains a significant global problem. Solar powered oxygen (SPO2) delivery is a reliable and cost-effective solution. We followed implementation research methodology to gather data on engineering parameters (remote monitoring), nurse training (before and after knowledge questionnaire), patients treated with SPO2 (descriptive case series), and qualitative user feedback (focus group discussions). In January 2021, SPO2 was installed at Hanano General Hospital in Dusamareb, Galmudug State, Somalia, in a conflict-affected region. Daily photovoltaic cell output (median 8.0 kWh, interquartile range (IQR) 2.6–14) exceeded the electrical load from up to three oxygen concentrators (median 5.0 kWh, IQR 0.90–12). Over the first six months after implementation, 114 patients (age 1 day to 89 years, 54% female) were treated for hypoxaemic illnesses, including COVID-19, pneumonia, neonatal asphyxia, asthma, and trauma. Qualitative end user feedback highlighted SPO2 acceptability. Violent conflict was identified as a contextual factor affecting local oxygen needs. We provide the preliminary findings of this implementation research study and describe the feasibility, fidelity, rapid adoption, usefulness, and acceptability of SPO2 in a low-resource setting characterized by violent conflict during the COVID-19 pandemic. Our findings demonstrated the lifesaving feasibility of SPO2 in volatile settings.