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result(s) for
"Fehrman, Emily A."
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Case-control study of autonomic symptoms in the setting of Long COVID with tilt table testing
2025
Autonomic symptoms and orthostatic syndromes have been reported in Long COVID, but few studies have characterized findings using head up tilt table testing.
To characterize autonomic responses to positional changes among individuals with Long COVID.
We assessed autonomic symptoms using the Composite Autonomic Symptom Scale 31 (COMPASS 31) instrument and performed head up tilt table testing for 30 minutes at 70 degrees among individuals with Long COVID and recovered comparators.
We included 26 participants (median age 56 years, 50% female median 25 months after first COVID): 16 with Long COVID and 10 recovered comparators. COMPASS 31 scores (0-100, higher is worse) were higher among those with Long COVID (median 30.5 vs 8, p = 0.003). Heart rate was 8 beats per minutes higher throughout tilt among those with Long COVID (95% CI 1.1 to 14.4; p = 0.02); there were no differences in blood pressure. Ten (63%) with Long COVID had symptoms during tilt compared to none among recovered participants (p = 0.003). Three (19%) with Long COVID had clinically abnormal findings: one each with orthostatic hypotension, and delayed orthostatic hypotension, and cardioinhibitory/vasovagal presyncope.
Among those with chronic autonomic symptoms in the setting of Long COVID, symptoms were common during tilt testing, and heart rate was increased, but most did not meet diagnostic criteria for a clinically abnormal hemodynamic response. Further research into mechanisms of autonomic symptoms in Long COVID is urgently needed.
Journal Article
Increased Mannosylation of Extracellular Vesicles in Long COVID Plasma as a Binding Target for Galanthus nivalis Agglutinin (GNA) Affinity Resin
by
Kelly, J Daniel
,
Deeks, Steven G
,
Peluso, Michael J
in
COVID-19 - blood
,
COVID-19 - metabolism
,
Disease
2026
There is no proven therapy for Long COVID, a post-acute condition characterized by persistent symptoms following SARS-CoV-2 infection. Extracellular vesicles (EVs) are emerging as mediators of disease pathogenesis through their molecular cargo. We investigated whether EV glycosylation is altered in Long COVID plasma and whether these vesicles can be selectively targeted using a glycan-binding affinity resin. Large (100-500 nm) and small (40-200 nm) EVs were isolated from post-acute COVID-19 plasma and analyzed by nanoparticle flow cytometry to assess surface glycosylation. Small EV capture assays were performed using
agglutinin (GNA) affinity resin. Plasma miRNA profiles before and after GNA treatment were evaluated using NanoString nCounter analysis, and potential downstream pathway effects were computationally inferred using validated miRNA-mRNA interactions and PROGENy. Mannose-positive large EVs were significantly increased in Long COVID compared to recovered controls (
< 0.05). GNA-mediated small EV capture correlated with mannose-positive EV abundance (r = 0.341,
< 0.05), and seven miRNAs were significantly reduced following treatment. Computational pathway analysis suggested modulation of key signaling pathways, including JAK-STAT, Estrogen, VEGF, and PI3K. These findings suggest a glycan-associated EV signature in Long COVID and support further investigation of lectin-based capture as a potential strategy to target vesicle-associated molecular cargo.
Journal Article
Persistence, Magnitude, and Patterns of Postacute Symptoms and Quality of Life Following Onset of SARS-CoV-2 Infection: Cohort Description and Approaches for Measurement
by
Romero, Mariela D
,
Deeks, Steven G
,
Durstenfeld, Matthew S
in
Asymptomatic
,
COVID-19
,
Infections
2022
Abstract
Background
There is mounting evidence for the presence of postacute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (PASC), but there is limited information on the spectrum, magnitude, duration, and patterns of these sequelae as well as their influence on quality of life.
Methods
We assembled a cohort of adults with a documented history of SARS-CoV-2 RNA positivity at ≥2 weeks past onset of coronavirus disease 2019 (COVID-19) symptoms or, if asymptomatic, first positive test. At 4-month intervals, we queried physical and mental health symptoms and quality of life.
Results
Of the first 179 participants enrolled, 10 were asymptomatic during the acute phase of SARS-CoV-2 infection, 125 were symptomatic but not hospitalized, and 44 were symptomatic and hospitalized. During the postacute phase, fatigue, shortness of breath, concentration problems, headaches, trouble sleeping, and anosmia/dysgeusia were most common through 8 months of observation. Symptoms were typically at least somewhat bothersome and sometimes exhibited a waxing-and-waning course. Some participants experienced symptoms of depression, anxiety, and post-traumatic stress, as well as difficulties with performance of usual activities. The median visual analogue scale rating of general health was lower at 4 and 8 months compared with pre-COVID-19. Two clusters of symptom domains were identified.
Conclusions
Many participants report bothersome symptoms following onset of COVID-19 with variable patterns of persistence and impact on quality of life. The substantial variability suggests the existence of multiple subphenotypes of PASC. A rigorous approach to the prospective measurement of symptoms and functional manifestations sets the stage for the next phase of research focusing on the pathophysiologic causes of the various subgroups of PASC.
Journal Article
Characterizing the COVID-19 Illness Experience to Inform the Study of Post-acute Sequelae and Recovery
2022
BackgroundThere is an urgent need to fully understand the impact of variable COVID-19 experiences and the optimal management of post-acute sequelae of SARS-CoV-2 infection. We characterized the variability in the acute illness experience and ongoing recovery process from participants in a COVID-19 recovery cohort study in Northern California in 2020.MethodWe completed 24 semi-structured in-depth interviews with adults with confirmed positive SARV-CoV-2 nucleic acid amplification test result, had recovered or were recovering from acute infection, and underwent serial evaluations. We purposefully sampled English- and Spanish-speaking adults with asymptomatic, mild, and severe symptomatic infection, including those who were hospitalized and those with HIV co-infection. We used a thematic analysis to analyze interviews and identify salient themes.ResultsAfter integrating the thematic analysis with clinical data, we identified key themes: (1) across symptom profiles and severity, experiencing COVID-19 was associated with psychological distress; (2) symptomatic infection carried uncertainty in symptom presentation and ongoing recovery (e.g., long COVID); and (3) health information-seeking behavior was facilitated by access to medical care and uncertainty with the recovery process.ConclusionOur data informs the emerging field of “long COVID” research and shows a need to provide information and continuous support to persons with post-acute sequelae to ensure they feel secure along the path to recovery.
Journal Article
Increased mannosylation of extracellular vesicles in Long COVID plasma provides a potential therapeutic target for Galanthus nivalis agglutinin (GNA) affinity resin
2025
There is no proven therapy for Long COVID, a post-acute illness characterized by a myriad of diverse symptoms including fatigue, dyspnea, and brain fog following SARS-CoV-2 infection. Extracellular vesicles (EVs) have been implicated in Long COVID pathogenesis by promoting viral and inflammatory signaling with their molecular cargo. In this study, we investigated whether EV abundance and glycome characteristics are altered in plasma from people with Long COVID and whether they can be targeted for removal using a glycan-binding affinity resin. Large (100-500 nm) and small (40-200 nm) EVs were isolated from plasma of participants in the post-acute phase of COVID-19 and analyzed by nanoparticle flow cytometry to measure concentration and glycan characteristics. Plasma of those with Long COVID contained elevated levels of both large and small EVs, and mannose-positive large EVs were significantly increased in comparison to recovered controls (p < 0.05). EV capture assays using
agglutinin (GNA) affinity resin demonstrated small EV removal positively correlated with mannose-positive EV abundance (r = 0.341, p < 0.05). NanoString analyses identified seven EV-associated miRNAs significantly depleted by GNA affinity resin treatment of plasma. PROGENy pathway inference of validated miRNA-mRNA interactions suggests these reductions may lead to a downregulation of JAK-STAT signaling and upregulation of Estrogen, VEGF, and PI3K pathways, resulting in a favorable rebalancing of immune and tissue-repair networks. These findings reveal specific glycome EV-miRNA cargo signatures in Long COVID and the potential clinical benefits of a lectin capture therapeutic strategy to remove these pathogenic vesicles and their inflammatory cargo.
Journal Article
First-in-human immunoPET imaging of HIV-1 infection using 89Zr-labeled VRC01 broadly neutralizing antibody
2022
A major obstacle to achieving long-term antiretroviral (ART) free remission or functional cure of HIV infection is the presence of persistently infected cells that establish a long-lived viral reservoir. HIV largely resides in anatomical regions that are inaccessible to routine sampling, however, and non-invasive methods to understand the longitudinal tissue-wide burden of HIV persistence are urgently needed. Positron emission tomography (PET) imaging is a promising strategy to identify and characterize the tissue-wide burden of HIV. Here, we assess the efficacy of using immunoPET imaging to characterize HIV reservoirs and identify anatomical foci of persistent viral transcriptional activity using a radiolabeled HIV Env-specific broadly neutralizing antibody,
89
Zr-VRC01, in HIV-infected individuals with detectable viremia and on suppressive ART compared to uninfected controls (NCT03729752). We also assess the relationship between PET tracer uptake in tissues and timing of ART initiation and direct HIV protein expression in CD4 T cells obtained from lymph node biopsies. We observe significant increases in
89
Zr-VRC01 uptake in various tissues (including lymph nodes and gut) in HIV-infected individuals with detectable viremia (
N
= 5) and on suppressive ART (
N
= 5) compared to uninfected controls (
N
= 5). Importantly, PET tracer uptake in inguinal lymph nodes in viremic and ART-suppressed participants significantly and positively correlates with HIV protein expression measured directly in tissue. Our strategy may allow non-invasive longitudinal characterization of residual HIV infection and lays the framework for the development of immunoPET imaging in a variety of other infectious diseases.
Here, the authors apply positron emission tomography (PET) imaging to visualize HIV tissue-wide burden in infected individuals using a radiolabeled broadly neutralizing antibody,
89
Zr-VRC01, and show that PET tracer lymph node uptake positively correlates with HIV protein levels measured directly from cells obtained from these tissues. This strategy may allow non-invasive characterization of residual HIV infection in the setting of therapeutic interventions.
Journal Article
First-in-human immunoPET imaging of HIV-1 infection using 89 Zr-labeled VRC01 broadly neutralizing antibody
by
Schulte, Brailee
,
Seo, Youngho
,
Deeks, Steven G
in
Antibodies, Neutralizing
,
Broadly Neutralizing Antibodies
,
CD4-Positive T-Lymphocytes
2022
A major obstacle to achieving long-term antiretroviral (ART) free remission or functional cure of HIV infection is the presence of persistently infected cells that establish a long-lived viral reservoir. HIV largely resides in anatomical regions that are inaccessible to routine sampling, however, and non-invasive methods to understand the longitudinal tissue-wide burden of HIV persistence are urgently needed. Positron emission tomography (PET) imaging is a promising strategy to identify and characterize the tissue-wide burden of HIV. Here, we assess the efficacy of using immunoPET imaging to characterize HIV reservoirs and identify anatomical foci of persistent viral transcriptional activity using a radiolabeled HIV Env-specific broadly neutralizing antibody,
Zr-VRC01, in HIV-infected individuals with detectable viremia and on suppressive ART compared to uninfected controls (NCT03729752). We also assess the relationship between PET tracer uptake in tissues and timing of ART initiation and direct HIV protein expression in CD4 T cells obtained from lymph node biopsies. We observe significant increases in
Zr-VRC01 uptake in various tissues (including lymph nodes and gut) in HIV-infected individuals with detectable viremia (N = 5) and on suppressive ART (N = 5) compared to uninfected controls (N = 5). Importantly, PET tracer uptake in inguinal lymph nodes in viremic and ART-suppressed participants significantly and positively correlates with HIV protein expression measured directly in tissue. Our strategy may allow non-invasive longitudinal characterization of residual HIV infection and lays the framework for the development of immunoPET imaging in a variety of other infectious diseases.
Journal Article
Fabrication of a deoxyribonucleic acid polymer ridge waveguide electro-optic modulator by nanoimprint lithography
2014
The purpose of this dissertation is to develop the nanoimprint lithography (NIL) technique for direct patterning of the deoxyribonucleic acid biopolymer DNA-CTMA. The Mach Zehnder modulator was chosen as the test device to demonstrate the NIL patterning technique for DNA-CTMA as well as the unique optical and electrical properties of the DNA-CTMA as a cladding material for poled electro-optic polymers. Towards this goal, a DNA-CTMA clad inverted ridge waveguide is demonstrated at 633 nm and 1550 nm, the structure of which is patterned directly in the DNA-CTMA cladding by NIL. Additionally, EO modulation is demonstrated in a slab waveguide structure with DNA-CTMA cladding and SEO110 EO polymer core. Marine-derived deoxyribonucleic acid biopolymer (DNA-CTMA) is a green, nontoxic, low cost optical polymer material derived from waste products of the salmon fishing industry. It exhibits low optical loss at 1550 nm, forms a thin flexible film, is compatible with existing poled polymer technologies, increases the poling efficiency when used as a low resistivity cladding layer, and is thermally stable to 200 oC. Due to chemical incompatibility with the photoresists and the associated solvents, NIL has been developed for patterning the DNA biopolymer cladding to form an inverted ridge waveguide for the basis of the Mach Zehnder modulator. While DNA-CTMA presents significant advantages over other commonly used cladding materials for the 1550 nm wavelength range, one of the commonly used bands for optical communications, the mechanical properties and environmental susceptibility of the material poses significant fabrication challenges. A study of the effects of optical and mechanical effects of environmental humidity exposure are presented for the DNA-CTMA and SEO110 polymers used in the inverted ridge waveguide. While the soft, flexible nature of the DNA-CTMA is desirable for certain applications, this presents a challenge in producing a clean polished window for optical coupling. Incompatibility with standard polishing techniques has led to the study of focused ion-beam milling (FIB) as a technique for polishing the DNA-CTMA film edge. This dissertation presents a demonstration at 633 nm and 1550 nm of an inverted ridge waveguide patterned by NIL in the DNA-CTMA cladding. Optical modulation in a slab waveguide structure consisting of the same polymer layers as the inverted ridge waveguide is also demonstrated, which together with waveguiding in an inverted ridge waveguide presents the case for the DNA-CTMA clad Mach Zehnder modulator. In this dissertation the FIB polishing technique for DNA-CTMA is demonstrated as a means to overcome the challenges of mechanically polishing the DNA-CTMA polymer. A study of the optical and mechanical effects of environmental exposure for DNA-CTMA and SEO110 is presented along with an analysis polymer film stresses as a result of fabrication processes and environmental exposures. This dissertation represents a significant advancement in fabrication techniques for DNA-CTMA thin films with the development of NIL for DNA-CTMA and is a significant step towards fully patterned DNA-CTMA EO waveguide devices.
Dissertation