Publications by authors named "Ian Mcdowell"

Article Synopsis
  • Lewy bodies (LBs), which are linked to Parkinson's disease (PD), can be formed in human dopaminergic neurons derived from induced pluripotent stem cells (iPSCs) when exposed to α-synuclein fibrils and immune challenges.
  • Immune response factors like interferon-γ and interleukin-1β, along with activated microglia, play a critical role in promoting this inclusion formation and impair lysosomal function.
  • The study suggests that LB-like inclusions may arise from disruptions in autophagy, highlighting a possible connection between immune dysfunction and PD development.
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CRISPR-Cas systems have proven effective in a variety of applications due to their ease of use and relatively high editing efficiency. Yet, any individual CRISPR-Cas system has inherent limitations, necessitating a diversity of RNA-guided nucleases to suit applications with distinct needs. We searched through metagenomic sequences to identify RNA-guided nucleases and found enzymes from diverse CRISPR-Cas types and subtypes, the most promising of which we developed into gene-editing platforms.

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Antibodies are critical reagents to detect and characterize proteins. It is commonly understood that many commercial antibodies do not recognize their intended targets, but information on the scope of the problem remains largely anecdotal, and as such, feasibility of the goal of at least one potent and specific antibody targeting each protein in a proteome cannot be assessed. Focusing on antibodies for human proteins, we have scaled a standardized characterization approach using parental and knockout cell lines (Laflamme et al.

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Evidence has long suggested that epidermal growth factor receptor (EGFR) may play a prominent role in triple-negative breast cancer (TNBC) pathogenesis, but clinical trials of EGFR inhibitors have yielded disappointing results. Using a candidate drug screen, we identified that inhibition of cyclin-dependent kinases 12 and 13 (CDK12/13) dramatically sensitizes diverse models of TNBC to EGFR blockade. This combination therapy drives cell death through the 4E-BP1-dependent suppression of the translation and translation-linked turnover of driver oncoproteins, including MYC.

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Objectives: To synthesize evidence relevant for informed decisions concerning cognitive testing of older physicians.

Methods: Relevant literature was systematically searched in Medline, EMBASE, PsycInfo, and ERIC, with key findings abstracted and synthesized.

Results: Cognitive abilities of physicians may decline in an age range where they are still practicing.

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Profilin-1, a member of the Profilin family, is a ubiquitously expressed protein that controls actin polymerization in a concentration-dependent manner. As mutations in the Profilin-1 gene have potential implications in neurodegenerative disease progression, well-characterized anti-Profilin-1 antibodies would be beneficial to the scientific community. In this study, we characterized sixteen Profilin-1 commercial antibodies for Western blot, immunoprecipitation, and immunofluorescence applications, using a standardized experimental protocol based on comparing read-outs in knockout cell lines and isogenic parental controls.

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Article Synopsis
  • - Antibodies are essential for detecting and studying proteins, but many commercial antibodies may not effectively target their intended proteins, a problem that remains mostly anecdotal; this study evaluates the performance of 614 commercial antibodies on 65 neuroscience-related proteins to quantify the issue.
  • - The research found that over 50% of tested antibodies failed in various assessments, yet around 50-75% of the protein targets had at least one high-performing antibody available, indicating a significant coverage of human proteins despite the issues.
  • - Notably, recombinant antibodies outperformed traditional monoclonal and polyclonal antibodies, and the study identified many poorly performing antibodies that had been widely used in publications, prompting manufacturers to reassess and improve their products
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Ubiquilin-2, a member of the ubiquilin protein family, plays a role in the regulation of various protein degradation pathways, and is mutated in some neurodegenerative diseases. Well-characterized anti-Ubiquilin-2 antibodies would advance reproducible research for Ubiquilin-2 and in turn, benefit the scientific community. In this study, we characterized ten Ubiquilin-2 commercial antibodies for Western Blot, immunoprecipitation, and immunofluorescence using a standardized experimental protocol based on comparing read-outs in knockout cell lines and isogenic parental controls.

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Article Synopsis
  • - The VOL4002 study evaluated the effects of volanesorsen on triglyceride levels and safety in 22 adults with familial chylomicronaemia syndrome (FCS) in the UK, combining data from both treatment-naive and previously treated patients.
  • - Participants receiving volanesorsen showed significant triglyceride reductions (up to 55% after 15 months) and a 74% decrease in pancreatitis events compared to a 5-year period before treatment, indicating the medication's efficacy in managing FCS symptoms.
  • - Safety assessments indicated that platelet counts remained stable, and no serious adverse effects were reported related to prolonged use, supporting the long-term use of volanesorsen for patients with FCS.
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Background: Mechanisms governing the diversity of CFTR gene expression throughout the body are complex. Multiple intronic and distal regulatory elements are responsible for regulating differential CFTR expression across tissues.

Methods: Drawing on published data, 18 high-priority genomic regions were identified and interrogated for CFTR-enhancer function using CRISPR/dCas9-based epigenome editing tools.

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Gene regulatory network inference is essential to uncover complex relationships among gene pathways and inform downstream experiments, ultimately enabling regulatory network re-engineering. Network inference from transcriptional time-series data requires accurate, interpretable, and efficient determination of causal relationships among thousands of genes. Here, we develop Bootstrap Elastic net regression from Time Series (BETS), a statistical framework based on Granger causality for the recovery of a directed gene network from transcriptional time-series data.

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Background And Aims: The UK Simon Broome (SB) familial hypercholesterolaemia (FH) register previously reported 3-fold higher standardised mortality ratio for cardiovascular disease (CVD) in women compared to men from 2009 to 2015. Here we examined sex differences in CVD morbidity in FH by national linkage of the SB register with Hospital Episode Statistics (HES).

Methods: Of 3553 FH individuals in the SB register (aged 20-79 years at registration), 2988 (52.

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Purpose Of Review: The role of non-HDL-C in the identification and management of lipid disorders is not clearly defined, although UK guidelines recommend its wider use in assessing the need for lipid-lowering therapy and as a treatment target.

Recent Findings: We examined the implications of the use of non-HDL-C as opposed to LDL-C in 253 people with hypercholesterolaemia before treatment and 573 after treatment in whom fasting total serum cholesterol, HDL-C and LDL-C had been recorded and the diagnosis of heterozygous familial hypercholesterolemia (heFH) was investigated by genetic testing. The difference and the limits of agreement between non-HDL-C and LDL-C calculated using the Friedewald formula were assessed in those with and without heFH-causing mutations.

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Objectives: Protests, riots and revolutions have long been a part of human history and are increasing globally, yet their impact on mental health remains largely unknown. We therefore systematically reviewed studies on collective actions and mental health.

Method: We searched PubMed, Web of Science, PsycINFO and CINAHL Plus for published studies from their inception until 1 January 2018.

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Environmental stimuli commonly act via changes in gene regulation. Human-genome-scale assays to measure such responses are indirect or require knowledge of the transcription factors (TFs) involved. Here, we present the use of human genome-wide high-throughput reporter assays to measure environmentally-responsive regulatory element activity.

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Background And Aims: The International Atherosclerosis Society (IAS) has proposed that patients with "severe" FH (SFH) would warrant early and more aggressive cholesterol-lowering treatment such as with PCSK9 inhibitors. SFH is diagnosed if LDL-cholesterol (LDLC) > 10 mmol/L, or LDLC >8.0 mmol/L plus one high-risk feature, or LDLC >5 mmol/L plus two high-risk features.

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Glucocorticoids are potent steroid hormones that regulate immunity and metabolism by activating the transcription factor (TF) activity of glucocorticoid receptor (GR). Previous models have proposed that DNA binding motifs and sites of chromatin accessibility predetermine GR binding and activity. However, there are vast excesses of both features relative to the number of GR binding sites.

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Background And Aim: Familial hypercholesterolaemia is caused by variants in the low-density lipoprotein cholesterol metabolic pathway involving LDLR, APOB and PCSK9 genes. A national genetic testing service in Wales, UK has observed that no familial hypercholesterolaemia variant is found in almost 80% patients with the familial hypercholesterolaemia phenotype. It has recently been suggested that some adult patients with a familial hypercholesterolaemia phenotype may have cholesteryl ester storage disease which can also present as a mixed hyperlipidaemia.

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The glucocorticoid receptor (GR) is a hormone-inducible transcription factor involved in metabolic and anti-inflammatory gene expression responses. To investigate what controls interactions between GR binding sites and their target genes, we used in situ Hi-C to generate high-resolution, genome-wide maps of chromatin interactions before and after glucocorticoid treatment. We found that GR binding to the genome typically does not cause new chromatin interactions to target genes but instead acts through chromatin interactions that already exist prior to hormone treatment.

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Transcriptome-wide time series expression profiling is used to characterize the cellular response to environmental perturbations. The first step to analyzing transcriptional response data is often to cluster genes with similar responses. Here, we present a nonparametric model-based method, Dirichlet process Gaussian process mixture model (DPGP), which jointly models data clusters with a Dirichlet process and temporal dependencies with Gaussian processes.

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Gene co-expression networks capture biologically important patterns in gene expression data, enabling functional analyses of genes, discovery of biomarkers, and interpretation of genetic variants. Most network analyses to date have been limited to assessing correlation between total gene expression levels in a single tissue or small sets of tissues. Here, we built networks that additionally capture the regulation of relative isoform abundance and splicing, along with tissue-specific connections unique to each of a diverse set of tissues.

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Gene regulation is fundamentally important for the coordination of diverse biologic processes including homeostasis and responses to developmental and environmental stimuli. Transcription factor (TF) binding sites are one of the major functional subunits of gene regulation. They are arranged in cis-regulatory modules (CRMs) that can be more active than the sum of their individual effects.

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Background: Transversions (Tv's) are more likely to alter the amino acid sequence of proteins than transitions (Ts's), and local deviations in the Ts:Tv ratio are indicative of evolutionary selection on genes. Whether the two different types of mutations have different effects in non-protein-coding sequences remains unknown. Genetic variants primarily impact gene expression by disrupting the binding of transcription factors (TFs) and other DNA-binding proteins.

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Objective: This study investigated genetic determinants of adiponectin during pregnancy to reveal novel biology of adipocyte regulation.

Methods: A genome-wide association study was conducted in 1,322 pregnant women from the Hyperglycemia and Adverse Pregnancy Outcome Study with adiponectin measured at ∼28 weeks of gestation. Variants reaching P < 5×10 for de novo genotyping in two replication cohorts (Genetics of Glycemic regulation in Gestation and Growth N = 522; ECOGENE-21 N = 174) were selected.

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