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At least 415 records · Page 23

Conclusions of a Mini Technical Interchange Meeting on Mechanisms and Pathways Common Between Adverse Health Outcomes from Exposures to Space Radiation

To enable deep space exploration and sustained human presence in space, the NASA Human Research Program’s (HRP) Space Radiation Element (SRE) funds research to characterize and mitigate adverse health outcomes from exposure to space radiation that include risks of carcinogenesis, cardiovascular disease (CVD) and central nervous system (CNS) decrements. Over the past decade, a growing body of compelling experimental evidence suggests shared mechanisms and pathophysiological processes for CVD, neurodegenerative effects, and cancer development and progression, which are traditionally managed as separate disease processes. Additionally, epidemiological studies have identified cross-sectional and longitudinal associations between some specific types of cancer and CVD, and accumulating evidence indicates that the pathogenesis of neurodegenerative diseases such as Alzheimer’s disease may overlap with CVD and cancer pathogenesis. Identifying the mechanisms and pathways common to these important health decrements will not only accelerate development of effective countermeasures and improve management of spaceflight-induced risk, it will also help to develop new treatment strategies for patients on Earth. To identify common pathways and mechanisms of disease induction and progression from current SR-funded studies and to inform future work and solicitations, the SRE organizes themed sessions at annual HRP Investigators’ Workshops (IWS). These technical interchange meetings (TIMs) provide a venue for the scientific community to present ongoing work and engage in open discussion on results, limitations of current approaches, and incorporation of novel experimental strategies, model systems, and other innovative techniques. Here a summary and lessons learned from the SRE-sponsored mini-TIM titled “mechanisms and pathways common between adverse health outcomes” held at HRP IWS 2023 will be communicated. The 90-min TIM had 30-min dedicated to discussing and developing potential collaboration and tissue sharing opportunities among investigators. The SRE facilitated the discussion using a set of pressing questions and gaps in knowledge that need to be addressed by the scientific community. This poster presents the outcomes of the session along with proposed future workshops and other SRE initiatives.

Janapriya Saha↗

Biological Space Radiation Countermeasures to Enable Long Duration Exploration Missions

NASA’s career radiation limit for astronauts is 600 mSv. Currently planned missions beyond low Earth orbit (LEO) will expose crew to at least double that amount of radiation (for Mars missions). Therefore, to enable long duration exploration, countermeasures need to be deployed to reduce the long-term health outcomes of space radiation exposure. Limitations to the ability of spacecraft to shield against the high energy charged particles of the space radiation environment necessitate alternative methods to reduce overall space radiation risk for carcinogenesis. Recent successes in the arenas of Acute Radiation Syndrome (ARS) and clinical radiotherapy have demonstrated the efficacy of compound-based/biologicals in reducing the detrimental long term health outcomes associated with space radiation exposure. In recent years, the Space Radiation Element has funded the investigation of several such compounds including Avasopasem Manganese, CDDO-Me, Metformin, and γ-tocotrienol. The demonstrated efficacy of these compounds in reducing carcinogenesis, central nervous system, and cardiovascular disease risks demonstrate the need for, and potential benefit of, a robust countermeasure identification and development program with an initial starting suite of compounds available to validate others. The authors would also like to present highlights of a recent Space Radiation Element sponsored issue of Life Sciences in Space Research entitled “Breaking the Limit” on this specific topic.

Space Radiation↗

Automated Fluidics Device for Extraction and Quantification of miRNA Biomarkers From Blood

Radiation Assessment DuRing Exposure And long-Duration Spaceflight (RADREADS) demonstrates space-compatible point-of-care technology for quantitative biological monitoring of blood miRNA biomarkers in response to long-term low dose radiation exposure. This individualized monitoring approach will inform targeted treatment strategies to maximize medical resource utilization by accounting for individual susceptibility to radiation-related illnesses. As human spaceflight progresses beyond Earth’s magnetic shielding, radiation exposure poses a significant risk to astronaut health and safety. Extended operation in this environment comes with an increased risk of radiation exposure, leading to higher risks of radiation sickness, cancer, central nervous system effects, and degenerative diseases. While conventional physical dosimetry techniques capture radiation dose, individualistic susceptibility to radiation damage is varied. Multiple characteristics, including age, body weight, sex, genetics, and immune status, have been found to influence radiosensitivity (Liu et al. 2011, and Bouffler 2016). This differential response necessitates individualized monitoring and targeted treatment strategies to maximize medical resource utilization; however, a practical diagnostic platform for quantifying long-term, low dose radiation-induced tissue damage does not currently exist. MicroRNAs (miRNAs) are a class of small, non-coding RNAs that regulate gene expression by mediating the degradation of messenger RNA. The levels of particular miRNAs are influenced by biological processes such as inflammation and serve as biomarkers for a variety of conditions including cancer (Singh et al. 2017). MicroRNAs are found in various bodily fluids and are amenable to collection via liquid biopsies, providing a minimally invasive and easily quantifiable readout for a variety of radiosensitive reporters. A preliminary signature of 15 spaceflight sensitive miRNA has been identified in rodent and human studies, including miR-21-5p, miR-24-3p, miR-92a-3p, miR-17-5p, miR-16a-3p, miR-34a-3p, and miR-223-3p. These targets generally increased expression with radiation dose and linear energy transfer, though variation between individuals is not yet described. Current gaps in the field include a lack of understanding of longitudinal biological responses to long-term, low dose radiation exposure and the absence of space-compatible point-of-care technology for quantitative biological monitoring. In this body of work, we aim to develop an automated bleed-to-read system to process whole blood for the detection of miRNA biomarkers in order to monitor individualistic responses to radiation exposure. This will be achieved via separating serum (or plasma) from whole blood, followed by extraction, amplification, and quantification of the miRNA using a RT-qPCR reaction. Previously, the WetLab-2 hardware enabled execution of a RT-qPCR reaction aboard ISS; however, it is a manual system that requires crew manipulation and bulky components (Parra et al. 2017). To address these issues, automated fluid handling hardware was developed for each stage of sample preparation. Extraction of total RNA is achieved by sequentially pumping reagents through an off-the-shelf nucleic acid binding column (miRNeasy Serum/Plasma Advanced Kit, Qiagen). This approach eliminates several manual pipetting and centrifuging steps and limits the use of toxic chemicals commonly found in other sample processing techniques. The resulting elution will then be automatically dispensed for RT-qPCR analysis using a compact rotary qPCR (Mic qPCR Cycler, Bio Molecular Systems) that will improve spaceflight compatibility by removing bubbles from the detection region, another challenge highlighted by WetLab-2 (Parra et al. 2017). Efforts are also being made to simplify the RT-qPCR reaction to a 1-step air-dryable mix to improve long-term reagent stability at room temperature and reduce system complexity. By automating the RT-qPCR processes via microfluidic manipulation, RADREADS will reduce crewmember hands-on time and enable the personalized detection of radiation-induced tissue damage during long duration missions. Minimally invasive, longitudinal monitoring of individual’s response to radiation exposure will inform how the physiological system responds to long-term low dose space radiation and enables development of targeted countermeasures by the medical team. Ultimately, this portable technology will require minimal technical expertise and can also be used to monitor miRNA biomarkers associated with other diseases.

Tristen Head↗

Conclusions of a Mini Technical Interchange Meeting on Mechanisms and Pathways Common Between Adverse Health Outcomes from Exposures to Space Radiation

To enable deep space exploration and sustained human presence in space, the NASA Human Research Program’s (HRP) Space Radiation Element (SRE) funds research to characterize and mitigate adverse health outcomes from exposure to space radiation that include risks of carcinogenesis, cardiovascular disease (CVD) and central nervous system (CNS) decrements. Over the past decade, a growing body of compelling experimental evidence suggests shared mechanisms and pathophysiological processes for CVD, neurodegenerative effects, and cancer development and progression, which are traditionally managed as separate disease processes. Additionally, epidemiological studies have identified cross-sectional and longitudinal associations between some specific types of cancer and CVD, and accumulating evidence indicates that the pathogenesis of neurodegenerative diseases such as Alzheimer’s disease may overlap with CVD and cancer pathogenesis. Identifying the mechanisms and pathways common to these important health decrements will not only accelerate development of effective countermeasures and improve management of spaceflight-induced risk, it will also help to develop new treatment strategies for patients on Earth. To identify common pathways and mechanisms of disease induction and progression from current SR-funded studies and to inform future work and solicitations, the SRE organizes themed sessions at annual HRP Investigators’ Workshops (IWS). These technical interchange meetings (TIMs) provide a venue for the scientific community to present ongoing work and engage in open discussion on results, limitations of current approaches, and incorporation of novel experimental strategies, model systems, and other innovative techniques. Here a summary and lessons learned from the SRE-sponsored mini-TIM titled “mechanisms and pathways common between adverse health outcomes” held at HRP IWS 2023 will be communicated. The 90-min TIM had 30-min dedicated to discussing and developing potential collaboration and tissue sharing opportunities among investigators. The SRE facilitated the discussion using a set of pressing questions and gaps in knowledge that need to be addressed by the scientific community. This poster presents the outcomes of the session along with proposed future workshops and other SRE initiatives.

Janapriya Saha↗

Comparison of Radiation-Induced Damage Between Livers From Control and Chimeric Mice

Assessment of human health risks associated with space radiation exposure is based largely on the knowledge gained from studies in which animals, mostly rodents, are exposed to high-LET radiation on the ground. It has been recognized that translation of animal results to meaningful implications for human disease can be challenging, particularly for certain risk categories such as the high-LET radiation effects in the central nervous system (CNS). Considering limitations in utilizing non-human primates and clinical studies in humans, chimeric animals can potentially bridge the knowledge gap between rodents and humans. In a chimeric animal, a specific organ or a cell type is replaced with respective human cells that are functional. In this pilot study, we used PXB mice whose livers contain >90% human cells. These mice were exposed to gamma rays to investigate DNA damage and transcriptomics changes in the chimeric livers. Results obtained from PXB mice were compared to non-engrafted control animals from the same background strain that were exposed to identical conditions. Staining of the liver tissues with H&E indicated that the human liver tissue in chimeric mice responded differently than the mouse liver tissue to gamma radiation on the cellular level, as evidenced by differences in inflammation and cellular damage seen on histopathology. The gene expression data collected from the liver samples will also be presented, which potentially offers an explanation for the differential responses.

Honglu Wu↗

Biological Space Radiation Countermeasures to Enable Long Duration Exploration Missions

NASA’s career radiation limit for astronauts is 600 mSv. Currently planned missions beyond low Earth orbit (LEO) will expose crew to at least double that amount of radiation (for Mars missions). Therefore, to enable long duration exploration, countermeasures need to be deployed to reduce the long-term health outcomes of space radiation exposure. Limitations to the ability of spacecraft to shield against the high energy charged particles of the space radiation environment necessitate alternative methods to reduce overall space radiation risk for carcinogenesis. Recent successes in the arenas of Acute Radiation Syndrome (ARS) and clinical radiotherapy have demonstrated the efficacy of compound-based/biologicals in reducing the detrimental long term health outcomes associated with space radiation exposure. In recent years, the Space Radiation Element has funded the investigation of several such compounds including Avasopasem Manganese, CDDO-Me, Metformin, and γ-tocotrienol. The demonstrated efficacy of these compounds in reducing carcinogenesis, central nervous system, and cardiovascular disease risks demonstrate the need for, and potential benefit of, a robust countermeasure identification and development program with an initial starting suite of compounds available to validate others. The authors would also like to present highlights of a recent Space Radiation Element sponsored issue of Life Sciences in Space Research entitled “Breaking the Limit” on this specific topic.

Space Radiation↗

Comparison of Radiation-Induced Damage Between Livers From Control and Chimeric Mice

Assessment of human health risks associated with space radiation exposure is based largely on the knowledge gained from studies in which animals, mostly rodents, are exposed to high-LET radiation on the ground. It has been recognized that translation of animal results to meaningful implications for human disease can be challenging, particularly for certain risk categories such as the high-LET radiation effects in the central nervous system (CNS). Considering limitations in utilizing non-human primates and clinical studies in humans, chimeric animals can potentially bridge the knowledge gap between rodents and humans. In a chimeric animal, a specific organ or a cell type is replaced with respective human cells that are functional. In this pilot study, we used PXB mice whose livers contain >90% human cells. These mice were exposed to gamma rays to investigate DNA damage and transcriptomics changes in the chimeric livers. Results obtained from PXB mice were compared to non-engrafted control animals from the same background strain that were exposed to identical conditions. Staining of the liver tissues with H&E indicated that the human liver tissue in chimeric mice responded differently than the mouse liver tissue to gamma radiation on the cellular level, as evidenced by differences in inflammation and cellular damage seen on histopathology. The gene expression data collected from the liver samples will also be presented, which potentially offers an explanation for the differential responses.

Honglu Wu↗

Neurobiological Outcomes of Mice Exposed to Combined Spaceflight Stressors

As NASA plans for exploration beyond Low-Earth Orbit, it is imperative to understand how deep spaceflight stressors impact human physiology. Deep space exposes crew members to multiple NASA-defined risks, including altered gravity, ionizing radiation, and social isolation. While the effects of individual stressors have been studied, there are still gaps in our understanding of their combined effects. In this study, we utilized the simulated five-ion galactic cosmic radiation (GCR) and isolation to assess the combinatorial effects of space stressors on the central nervous system (CNS) in mice. Our study captures sexually dimorphic responses by quantifying CNS outcomes in crewage-matched male and female mice. We assessed CNS responses in mice exposed to four days of isolation, followed by three different dosage of acute radiation exposure (5 cGy, 15 cGy, and 50 cGy 5-ion GCRsim). Comprehensive hippocampal cytokine biomarker analyses were conducted in both males and females at two weeks post-irradiation (intermediate cohort) and 124 days post-irradiation (delayed cohort). Proteomics on hippocampal lysates were conducted in the delayed cohort. Our results provide evidence for sex-specific differentially regulated hippocampal cytokines and proteomic profiles. Immunohistochemical analysis of the mice brain from intermediate and delayed cohorts is currently underway for multiple protein markers, including microglial activation, astrocytes, and dopaminergic neuronal population, among others. This project closely aligns with NASA’s efforts to characterize sex-specific risks associated with deep space exploration. We anticipate the results from this project will aid in our understanding of spaceflight stressors to ensure crew health and performance.

spaceflight↗

Long-term effects of acute irradiation and isolation on crew age-matched mice

The future of space missions beyond low-Earth orbit presents exciting opportunities but may come with formidable health challenges. Astronauts face a unique combination of space stressors capable of exerting effects on the central nervous system (CNS) with possible sex-dependent differences. The interaction of these combined spaceflight stressors may induce oxidative stress, thereby altering brain integrity and behavioral performance. Understanding these changes is critical for safeguarding astronaut health and enabling successful exploration. By understanding the physiological responses to the combined effects of ionizing radiation (IR) and social isolation in the brain through immunohistochemistry (IHC), proteomics and cytokine expression analyses, we aim to identify CNS pathways ripe for countermeasure development to mitigate adverse brain changes with future deep space exploration. Here, we study the combined effects of simulated 5-ion galactic cosmic radiation (GCRsim) at acute dosage (5, 15, and 50 cGy) and social isolation on crew age-matched male and female mice at 124 days post-irradiation. We conducted analyses of hippocampal cytokine biomarkers and proteomic profiling on hippocampal lysates. Our findings reveal sex-specific regulation of hippocampal cytokines and proteomic profiles. Ongoing immunohistochemistry findings on the hippocampus will provide qualitative information regarding key protein expression and cellular changes such as microglial activation, blood brain barrier integrity, and neuroinflammation. With future plans for long-duration space missions, such as Mars exploration, understanding CNS changes over extended periods in mice can provide insights into potential long-term health impacts on astronauts. This project will provide us with valuable insights into sex-differences in neurobiological processes and disease mechanisms impacting men and women in space.

space radiation↗

Conclusions of a Mini Technical Interchange Meeting on New Cross Risk Integration Projects Managed by the NASA Space Radiation Element

To enable deep space exploration and sustained human presence in space, the NASA Human Research Program’s (HRP) Space Radiation Element (SRE) funds research to characterize and mitigate adverse health outcomes from exposure to space radiation that include risks of carcinogenesis, cardiovascular disease, and central nervous system decrements. Recently, the SRE was tasked with supporting multiple HRP Elements with innovative and enabling projects to inform risk characterization, facilitate mitigation activities, and support crew health and performance. These projects, such as precision health initiative, NASA Omics Archive (NOA) and human sample repositories, are agnostic to any HRP Element, hence the name, Cross-Risk Integration Projects (CRIP). CRIP serves 3 broad purposes: - Services: Generate samples and data and manage the receipt, inventory, archive, and ultimate redistribution of biospecimens created in HRP-funded spaceflight and analog research activities—includes NASA Omics Archive project and various human and animal sample repositories. - Method Development: Identify and evaluate new-to-NASA research or analysis methods or techniques that could fundamentally improve existing or planned research efforts—includes the Translational Radiation Research and Countermeasures Project. - Enabling Capabilities: Demonstrate real-world application by adapting, adopting, and/or developing capabilities to benefit crew health and performance and improve risk mitigation—includes Precision Health Initiative (Pharmacogenomics) and advanced biological systems and engineered tissue microsystems initiative (tissue chips, organ-on-a-chip). To identify new technologies, future work, and solicitations, the SRE organizes themed sessions at annual HRP Investigators’ Workshops (IWS). These technical interchange meetings (TIMs) provide a venue for the scientific community to present ongoing work and engage in open discussion of results, limitations of current approaches, and incorporation of novel experimental strategies, model systems, and other innovative techniques. Here, a summary of the studies presented at the SRE-sponsored mini-TIM at the HRP IWS along with the goals and objectives of the CRIP projects is communicated. The 90-min TIM had 6 speakers who presented impressive novel ideas and work, some of which are funded under CRIP by the Space Radiation Element.

Janapriya Saha↗

yippee like 3 (ypel3) is a novel gene required for myelinating and perineurial glia development

Hypomyelination, a neurological disorder characterized by a decrease in the production of myelin sheets by glial cells, often has no known etiology. Elucidating the genetic causes of hypomyelination provides a better understanding of myelination, as well as means to diagnose, council, and treat patients. Here, we present evidence that YIPPEE LIKE 3 (YPEL3), a gene whose developmental role was previously unknown, is required for central and peripheral glial cell development. We identified a child with a constellation of clinical features including cerebral hypomyelination, abnormal peripheral nerve conduction, hypotonia, areflexia, and hypertrophic peripheral nerves. Exome and genome sequencing revealed a de novo mutation that creates a frameshift in the open reading frame of YPEL3 , leading to an early stop codon. We used zebrafish as a model system to validate that YPEL3 mutations are causative of neuropathy. We found that ypel3 isexpressed in the zebrafish central and peripheral nervous system. Using CRISPR/Cas9 technology, we created zebrafish mutants carrying a genomic lesion similar to that of the patient. Our analysis revealed that Ypel3 is required for specification and migration of myelinating oligodendrocytes, timely exit of the perineurial glial precursors from the central nervous system (CNS), formation of the perineurium, and Schwann cell maturation. Consistent with these observations, zebrafish ypel3 mutants have metabolomic signatures characteristic of oligodendrocyte and Schwann cell differentiation defects, show decreased levels of Myelin basic protein in the central and peripheral nervous system, and develop defasciculated peripheral nerves. Locomotion defects were observed in adult zebrafish ypel3 mutants. These studies demonstrate that Ypel3 is a novel gene required for perineurial cell differentiation and glial myelination.

59 BASIC BIOLOGICAL SCIENCES↗

A Ranked-Orbital Approach to Select Active Spaces for High-Throughput Multireference Computation

The past decade has seen a great increase in the application of high-throughput computation to a variety of important problems in chemistry. However, one area which has been resistant to the high-throughput approach is multireference wave function methods, in large part due to the technicalities of setting up these calculations and in particular the not always intuitive challenge of active space selection. As we look toward a future of applying high-throughput computation to all areas of chemistry, it is important to prepare these methods for large-scale automation. Here, we propose a ranked-orbital approach to select active spaces with the goal of standardizing multireference methods for high-throughput computation. This method allows for the meaningful comparison of different active space selection schemes and orbital localizations, and we demonstrate the utility of this approach across 1120 multireference calculations for the excitation energies of small molecules. Our results reveal that it is helpful to distinguish the method used to generate orbitals from the method of ranking orbitals in terms of importance for the active space. Additionally, we propose our own orbital ranking scheme that estimates the importance of an orbital for the active space through a pair-interaction framework from orbital energies and features of the Hartree–Fock exchange matrix. Here, we call this new scheme the “approximate pair coefficient” (APC) method and we show that it performs quite well for the test systems presented.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Behavioral and Physiological Effects of Hindlimb Unloading in Rats

The overarching objective of this project was to identify changes in neural and biochemical systems of the central and peripheral nervous systems (the CNS and PNS) that are related to disruptions of functional motor responses, or motor control. The identification of neural and biochemical changes that are related to sensory-motor adaptation elicited as animals react to changes in the gravitational field was of particular interest. Thus, the major objective of this work was to study disruptions of motor responses that arise after (sic. due to) chronic exposure to altered gravity (G). To do this, parallel studies investigating changes in neural, sensory, and neuromuscular systems were conducted after animals (rats) experienced chronic exposure to conditions of altered-G. Conditions of altered-G included hyper-G produced by centrifugation, micro-G produced by orbital flight, and simulated micro-G produced by hind limb suspension. A second major interest was to examine the contribution of putative changes in sensory systems to disruptions of motor responses. To do this, motor responses and reflexes of rats were studied following chronic treatment with streptomycin sulfate (STP, an ototoxic chemical) to damage the vestibular hair cells.

Fox, Robert A.↗

Long-term changes in amphetamine-induced reinforcement and aversion in rats following exposure to 56Fe particle

Exposing rats to heavy particles produces alterations in the functioning of dopaminergic neurons and in the behaviors that depend upon the integrity of the dopaminergic system. Two of these dopamine-dependent behaviors include amphetamine-induced reinforcement, measure using the conditioned place preference procedure, and amphetamine-induced reinforcement, measured using the conditioned place preference procedure, and amphetamine-induced aversion, measured using the conditioned taste aversion. Previous research has shown that exposing rats to 1.0 Gy of 1GeV/n 56Fe particles produced a disruption of an amphetamine-induced taste aversion 3 days following exposure, but produced an apparent enhancement of the aversion 112 days following exposure. The present experiments were designed to provide a further evaluation of these results by examining taste aversion learning 154 days following exposure to 1.0 Gy 56Fe particles and to establish the convergent validity of the taste aversion results by looking at the effects of exposure on the establishment of an amphetamine-induced conditioned place preference 3, 7, and 16 weeks following irradiation. The taste aversion results failed to confirm the apparent enhancement of the amphetamine-induced CTA observed in the prior experiment. However, exposure to 56Fe particles prevented the acquisition of amphetamine-induced place preference at all three-time intervals. The results are interpreted as indicating that exposure to heavy particles can produce long-term changes in behavioral functioning. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Non-NASA Center↗

Galactic cosmic ray simulation at the NASA space radiation laboratory – Progress, challenges and recommendations on mixed-field effects

For missions beyond low Earth orbit to the moon or Mars, space explorers will encounter a complex radiation field composed of various ion species with a broad range of energies. Such missions pose significant radiation protection challenges that need to be solved in order to minimize exposures and associated health risks. An innovative galactic cosmic ray simulator (GCRsim) was recently developed at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL). The GCRsim technology is intended to represent major components of the space radiation environment in a ground analog laboratory setting where it can be used to improve understanding of biological risks and serve as a testbed for countermeasure development and validation. The current GCRsim consists of 33 energetic ion beams that collectively simulate the primary and secondary GCR field encountered by humans in space over the broad range of particle types, energies, and linear energy transfer (LET) of interest to health effects. A virtual workshop was held in December 2020 to assess the status of the NASA baseline GCRsim. Workshop attendees examined various aspects of simulator design, with a particular emphasis on beam selection strategies. Experimental results, modeling approaches, areas of consensus, and questions of concern were also discussed in detail. This report includes a summary of the GCRsim workshop and a description of the current status of the GCRsim. This information is important for future advancements and applications in space radiobiology.

79 ASTRONOMY AND ASTROPHYSICS↗

OzMALDI: A Gas-Phase, In-Source Ozonolysis Reaction for Efficient Double-Bond Assignment in Mass Spectrometry Imaging with Matrix-Assisted Laser Desorption/Ionization

Lipids make up an important class of biomolecules with diverse structures and varied chemical functions. This diversity is a major challenge in chemical analysis and limits our understanding of biological functions and regulation. A major way lipid isomers differ is by double-bond (db) position, and analyzing db-isomers is especially challenging for mass spectrometry imaging (MSI). Ozonolysis can be used to determine the dbposition and has been paired with MSI before. However, previous techniques require increased analysis time to allow for gas-phase reactions within an ion trap or ion mobility cell or additional sample preparation time to allow for offline ozonation. Here, we introduce a new ozonolysis method inside the matrix-assisted laser desorption-ionization (MALDI) source, termed OzMALDI, that simultaneously produces ozonides from all unsaturated lipids. This allows us to determine db-positions without adding additional reaction time while maintaining the high mass resolution provided by Orbitrap MS. This new technique is especially effective at determining multiple db-positions in lipids containing polyunsaturated fatty acids, which is a limitation of many previous techniques. OzMALDI-MSI was applied to the analysis of rat brain and genetically engineered Camelina and soybean seed samples, demonstrating the utility of this method and uncovering novel biological information.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Statistically Driven Metabolite and Lipid Profiling of Patients from the Undiagnosed Diseases Network

Advancements in molecular separations coupled with mass spectrometry have enabled large-scale metabolome analyses for clinical cohorts. A population of interest for metabolome profiling are patients with rare disease for which abnormal metabolic signatures may yield clues into the genetic bases, as well as mechanistic drivers of the disease and possible treatment options. We undertook the metabolome profiling of a large cohort of patients with mysterious conditions characterized through the Un-diagnosed Diseases Network (UDN). Due to the size and enrollment procedures, collection of the metabolomes for UDN pa-tients took place over three years. We describe the study design to adjust for measurements collected over a long time-scale and how this enabled statistical analyses to summarize the metabolome of individual patients. We demonstrate the removal of time-based batch effects, overall statistical characteristics of the UDN population, and two case-studies of interest that demonstrate the utility of metabolome profiling for rare diseases.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗