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Biology subjects

Young, B. E.

Publications and source records attributed to Young, B. E..

6 recordsLinked to original sources

Insect Pollinators: The Time is Now for Identifying Species of Greatest Conservation Need

Severe declines in the abundance of insects, including economically and ecologically important pollinators are alarming conservationists and the public. Yet despite these increasingly well documented declines, relatively few pollinating insects other than some butterflies and bumble bees have appeared as Species of Greatest Conservation Need (SGCN) in State Wildlife Action Plans, decadal-scale blueprints for wildlife conservation efforts across the United States that require updating in 2025. Species absent from SGCN lists are ineligible for congressionally appropriated State Wildlife Grants that direct millions of dollars annually for their conservation. In the past, knowledge about the distribution and abundance of many insect pollinators was too poor to identify those meeting state guidelines for inclusion as SGCN. Using case studies from 4 northeastern states, we demonstrate that sufficient conservation status data now exists for many pollinators, including bees, butterflies, moths, beetles, and flower flies, to identify at-risk species meriting inclusion on SGCN lists in many states. Doing so will increase funding available for surveys, habitat protection and enhancement, and other conservation activities that will benefit this vitally important guild.

ecology↗

Continuous optical detection of small-molecule analytes in complex biomatrices

Current technology for measuring specific biomarkers - continuously in complex samples, without sample preparation - is limited to just handful of molecules such as glucose and blood oxygen. In this work, we present the first optical biosensor system that enables continuous detection of a wide range of biomarkers in complex samples, such as human plasma. Our system employs a modular duplex-bubble switch (DBS) architecture that converts aptamers into structure-switching fluorescence probes whose affinity and kinetics can be readily tuned. These DBS constructs are coupled to a fiber-optic detector that measures the fluorescence change only within an evanescent field, thereby minimizing the impact of background autofluorescence and enabling direct detection of analytes at physiologically relevant concentrations even in interferent-rich sample matrices. Using our system, we achieved continuous detection of dopamine in artificial cerebrospinal fluid for >24 hours with sub-second resolution and a limit of detection (LOD) of 1 {micro}M. We subsequently demonstrated the systems generalizability by configuring it to detect cortisol with nanomolar sensitivity in undiluted human plasma. Both sensors achieved LODs orders of magnitude lower than the KD of the DBS element, highlighting the potential to achieve sensitive detection even when using aptamers with modest affinity.

biophysics↗

Data-driven analysis of COVID-19 reveals specific severity patterns distinct from the temporal immune response

Key immune signatures of SARS-CoV-2 infection may associate with either adverse immune reactions (severity) or simply an ongoing anti-viral response (temporality); how immune signatures contribute to severe manifestations and/or temporal progression of disease and whether longer disease duration correlates with severity remain unknown. Patient blood was comprehensively immunophenotyped via mass cytometry and multiplex cytokine arrays, leading to the identification of 327 basic subsets that were further stratified into more than 5000 immunotypes and correlated with 28 plasma cytokines. Low-density neutrophil abundance was closely correlated with hepatocyte growth factor levels, which in turn correlated with disease severity. Deep analysis also revealed additional players, namely conventional type 2 dendritic cells, natural killer T cells, plasmablasts and CD16+ monocytes, that can influence COVID-19 severity independent of temporal progression. Herein, we provide interactive network analysis and data visualization tools to facilitate data mining and hypothesis generation for elucidating COVID-19 pathogenesis.

immunology↗

Early induction of SARS-CoV-2 specific T cells associates with rapid viral clearance and mild disease in COVID-19 patients

Virus-specific humoral and cellular immunity act synergistically to protect the host from viral infection. We interrogated the dynamic changes of virological and immunological parameters in 12 patients with symptomatic acute SARS-CoV-2 infection from disease onset to convalescence or death. We quantified SARS-CoV-2 viral RNA in the respiratory tract in parallel with antibodies and circulating T cells specific for various structural (NP, M, ORF3a and spike) and non-structural proteins (ORF7/8, NSP7 and NSP13). We observed that while rapid induction and quantity of humoral responses were associated with increased disease severity, an early induction of SARS-CoV-2 specific T cells was present in patients with mild disease and accelerated viral clearance. These findings provide further support for a protective role of SARS-CoV-2 specific T cells over antibodies during SARS-CoV-2 infection with important implications in vaccine design and immune-monitoring.

immunology↗

Whole blood immunophenotyping uncovers immature neutrophil-to-VD2 T-cell ratio as an early prognostic marker for severe COVID-19

SARS-CoV-2 is the novel coronavirus responsible for the current COVID-19 pandemic. Severe complications are observed only in a small proportion of infected patients but the cellular mechanisms underlying this progression are still unknown. Comprehensive flow cytometry of whole blood samples from 54 COVID-19 patients revealed a dramatic increase in the number of immature neutrophils. This increase strongly correlated with disease severity and was associated with elevated IL-6 and IP-10 levels, two key players in the cytokine storm. The most pronounced decrease in cell counts was observed for CD8 T-cells and VD2 {gamma}{delta} T-cells, which both exhibited increased differentiation and activation. ROC analysis revealed that the count ratio of immature neutrophils to CD8 or VD2 T-cells predicts pneumonia onset (0.9071) as well as hypoxia onset (0.8908) with high sensitivity and specificity. It would thus be a useful prognostic marker for preventive patient management and improved healthcare resource management.

immunology↗

Potent neutralizing antibodies in the sera of convalescent COVID-19 patients are directed against conserved linear epitopes on the SARS-CoV-2 spike protein

The ongoing SARS-CoV-2 pandemic demands rapid identification of immunogenic targets for the design of efficient vaccines and serological detection tools. In this report, using pools of overlapping linear peptides and functional assays, we present two immunodominant regions on the spike glycoprotein that were highly recognized by neutralizing antibodies in the sera of COVID-19 convalescent patients. One is highly specific to SARS-CoV-2, and the other is a potential pan-coronavirus target.

immunology↗