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Biology subjects

McBride, D.

Publications and source records attributed to McBride, D..

3 recordsLinked to original sources

Evening blue light exposure during adolescence induces avoidance behaviors and rewires medial amygdala circuit.

Adolescents are being increasingly exposed to artificial blue light from electronic devices, raising concerns about its effects on brain development and mental health. The medial amygdala (MeA), a brain region critical for emotional regulation, is light-sensitive, yet how evening blue light during puberty influences its circuitry and behavior remains unknown. Using a light cycle disruption paradigm, we found that adolescent mice exposed to evening blue light displayed increased avoidance behaviors compared to those exposed to darkness or reduced blue light conditions. Single-nuclei RNA sequencing revealed altered cell-type composition and disrupted synaptic communication pathways in the MeA. In vivo calcium imaging showed increased activity in MeA somatostatin neurons during avoidance behaviors, while chemogenetic inhibition of these neurons reduced these behaviors. Our findings identify the MeA as a key integrator of emotional responses to environmental blue light, suggesting evening blue light exposure during puberty as a potential risk factor for affective disorders. TeaserEvening blue light exposure during adolescence alters medial amygdala functions, leading to anxiety-like behaviors.

neuroscience↗

Surveillance for SARS-CoV-2 in Ohio's wildlife, companion, and agricultural animals

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in humans in late 2019 and spread rapidly to become a global pandemic. A zoonotic spillover event from animal to human was identified as the presumed origin. Subsequently, reports began emerging regarding spillback events resulting in SARS-CoV-2 infections in multiple animal species. These events highlighted critical links between animal and human health while also raising concerns about the development of new reservoir hosts and potential viral mutations that could alter virulence and transmission or evade immune responses. Characterizing susceptibility, prevalence, and transmission between animal species became a priority to help protect animal and human health. In this study, we coalesced a large team of investigators and community partners to surveil for SARS-CoV-2 in domestic and free-ranging animals around Ohio between May 2020 and August 2021. We focused on species with known or predicted susceptibility to SARS-CoV-2 infection, highly congregated or medically compromised animals (e.g. shelters, barns, veterinary hospitals), and animals that had frequent contact with humans (e.g. pets, agricultural animals, zoo animals, or animals in wildlife hospitals). This included free-ranging deer (n=76), mink (n=57), multiple species of bats (n=65), and other wildlife in addition to domestic cats (n=275) and pigs (n= 184). In total, we tested 800 animals (34 species) via rRT-PCR for SARS-CoV-2 RNA. SARS-CoV-2 viral RNA was not detected in any of the tested animals despite a major peak in human SARS-CoV-2 cases that occurred in Ohio subsequent to the peak of animal samplings. Importantly, due to lack of validated tests for animals, we did not test for SARS-CoV-2 antibodies in this study, which limited our ability to assess exposure. While the results of this study were negative, the surveillance effort was critical and remains key to understanding, predicting, and preventing re-emergence of SARS-CoV-2 in humans or animals.

microbiology↗

Immune-responsive biodegradable scaffolds for enhancing neutrophil regeneration

Neutrophils are essential effector cells for mediating rapid host defense and their insufficiency arising from therapy-induced side-effects, termed neutropenia, can lead to immunodeficiency-associated complications. In autologous hematopoietic stem cell transplantation (HSCT), neutropenia is a complication that limits therapeutic efficacy. Here, we report the development and in vivo evaluation of an injectable, biodegradable hyaluronic acid (HA)-based scaffold, termed HA cryogel, with myeloid responsive degradation behavior. In mouse models of immune deficiency, we show that the infiltration of functional myeloid-lineage cells, specifically neutrophils, is essential to mediate HA cryogel degradation. Post-HSCT neutropenia in recipient mice delayed degradation of HA cryogels by up to 3 weeks. We harnessed the neutrophil-responsive degradation to sustain the release of granulocyte colony stimulating factor (G-CSF) from HA cryogels. Sustained release of G-CSF from HA cryogels enhanced post-HSCT neutrophil recovery, comparable to pegylated G-CSF, which, in turn, accelerated cryogel degradation. HA cryogels are a potential approach for enhancing neutrophils and concurrently assessing immune recovery in neutropenic hosts.

bioengineering↗