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Kidd, S.

Publications and source records attributed to Kidd, S..

3 recordsLinked to original sources

Peripheral Neuropathy After Chronic Alcohol Exposure in Mice: Impact of sex, total intake and duration and alcohol metabolism.

Alcohol induced peripheral neuropathy (AIPN) is a neurodegenerative disease caused by chronic alcohol intake and is associated with peripheral nerve damage and somatosensory symptoms, such as allodynia. Current treatments lack efficacy and do not target underlying pathology emphasizing the need for preclinical models of AIPN to elucidate mechanisms and novel targets. Thus, we performed a detailed characterization of a mouse model of AIPN and candidate mechanistic associations including the role of neuroinflammation and acetaldehyde. Our studies showed chronic alcohol induced mechanical and cold hypersensitivity and deficits in spontaneous behaviors in EtOH concentration-, time- and sex-dependent manners. Female mice drank more alcohol and developed more rapid and severe hypersensitivity but less robust deficits of spontaneous behaviors. The grimace test demonstrated chronic alcohol promoted spontaneous pain independent of sex. Duration of intake impacted alcohol-induced deficits in peripheral nerve electrophysiology amplitude and intra-epidermal nerve fiber density. We characterized an extensive time-course of chronic alcohol-induced neuroinflammation in the DRG and spinal cord and found significant time, sex and tissue effects. Polymorphisms of ALDH2 have been associated with alcohol-induced neuroinflammation, alcohol-related pain, and alcohol-induced peripheral neuropathy. We investigated the role of acetaldehyde, via inhibition of ALDH2, in the development of AIPN and showed that ALDH2 inhibition accelerated and exacerbated development of chronic alcohol-induced hypersensitivity in male and female mice. Overall, our studies in a well-controlled model of AIPN strongly point to neuroinflammation and inflammatory modulators such as acetaldehyde as important mechanistic targets for possible intervention in AIPN.

pharmacology and toxicology↗

Tango-seq: overlaying transcriptomics on connectomics to identify neurons downstream of Drosophila clock neurons

Knowing how neural circuits change with neuronal plasticity and differ between individuals is important to fully understand behavior. Connectomes are typically assembled using electron microscopy, but this is low throughput and impractical for analyzing plasticity or mutations. Here, we modified the trans-Tango genetic circuit-tracing technique to identify neurons synaptically downstream of Drosophila s-LNv clock neurons, which show 24hr plasticity rhythms. s-LNv target neurons were labeled specifically in adult flies using a nuclear reporter gene, which facilitated their purification and then single cell sequencing. We call this Tango-seq, and it allows transcriptomic data - and thus cell identity - to be overlayed on top of anatomical data. We found that s-LNvs preferentially make synaptic connections with a subset of the CNMa+ DN1p clock neurons, and that these are likely plastic connections. We also identified synaptic connections between s-LNvs and mushroom body Kenyon cells. Tango-seq should be a useful addition to the connectomics toolkit.

neuroscience↗

SARS-CoV-2 genomics beyond the consensus sequence: evidence for circulating mixed viral populations

Extensive global sampling and whole genome sequencing of the pandemic virus SARS-CoV-2 have enabled researchers to characterise its spread, and to identify mutations that may increase transmission or enable the virus to escape therapies or vaccines. Two important components of viral spread are how frequently variants arise within individuals, and how likely they are to be transmitted. Here, we characterise the within-host diversity of SARS-CoV-2, and the extent to which genetic diversity is transmitted, by quantifying variant frequencies in 1390 clinical samples from the UK, many from individuals in known epidemiological clusters. We show that SARS-CoV-2 infections are characterised by low levels of within-host diversity across the entire viral genome, with evidence of strong evolutionary constraint in Spike, a key target of vaccines and antibody-based therapies. Although within-host variants can be observed in multiple individuals in the same phylogenetic or epidemiological cluster, highly infectious individuals with high viral load carry only a limited repertoire of viral diversity. Most viral variants are either lost, or occasionally fixed, at the point of transmission, consistent with a narrow transmission bottleneck. These results suggest potential vaccine-escape mutations are likely to be rare in infectious individuals. Nonetheless, we identified Spike variants present in multiple individuals that may affect receptor binding or neutralisation by antibodies. Since the fitness advantage of escape mutations in highly-vaccinated populations is likely to be substantial, resulting in rapid spread if and when they do emerge, these findings underline the need for continued vigilance and monitoring.

genomics↗