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1.
J Lesbian Stud ; : 1-14, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38783535

ABSTRACT

Britain has recently gained notoriety as a global hotspot for anti-trans politics and 'gender critical' feminism. But what is the relationship between British 'gender critical' politics and the transnational 'anti-gender' movement? Does Britain's gender critical feminism directly align with the global trends of anti-gender mobilisations, including the latter's authoritarian and neofascist tendencies? This commentary argues for a context-specific analysis of the British gender-critical movement which is attentive to its divergent political orientations. While some strands of gender-critical politics are openly allied with far-right politics and are explicitly anti-feminist, others include prominent figures from left-wing positions, including left feminists and lesbians. Challenging gender-critical politics in Britain requires a reckoning with its cross-political nature and an analysis of the factors that unite these different strands across left and right.

2.
EClinicalMedicine ; 36: 100910, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34124634

ABSTRACT

BACKGROUND: Antimicrobial resistance (AMR) in Enterobacterales is a global health threat. Capacity for individual-level surveillance remains limited in many countries, whilst population-level surveillance approaches could inform empiric antibiotic treatment guidelines. METHODS: In this exploratory study, a novel approach to population-level prediction of AMR in Enterobacterales clinical isolates using metagenomic (Illumina) profiling of pooled DNA extracts from human faecal samples was developed and tested. Taxonomic and AMR gene profiles were used to derive taxonomy-adjusted population-level AMR metrics. Bayesian modelling, and model comparison based on cross-validation, were used to evaluate the capacity of each metric to predict the number of resistant Enterobacterales invasive infections at a population-level, using available bloodstream/cerebrospinal fluid infection data. FINDINGS: Population metagenomes comprised samples from 177, 157, and 156 individuals in Kenya, the UK, and Cambodia, respectively, collected between September 2014 and April 2016. Clinical data from independent populations included 910, 3356 and 197 bacterial isolates from blood/cerebrospinal fluid infections in Kenya, the UK and Cambodia, respectively (samples collected between January 2010 and May 2017). Enterobacterales were common colonisers and pathogens, and faecal taxonomic/AMR gene distributions and proportions of antimicrobial-resistant Enterobacterales infections differed by setting. A model including terms reflecting the metagenomic abundance of the commonest clinical Enterobacterales species, and of AMR genes known to either increase the minimum inhibitory concentration (MIC) or confer clinically-relevant resistance, had a higher predictive performance in determining population-level resistance in clinical Enterobacterales isolates compared to models considering only AMR gene information, only taxonomic information, or an intercept-only baseline model (difference in expected log predictive density compared to best model, estimated using leave-one-out cross-validation: intercept-only model = -223 [95% credible interval (CI): -330,-116]; model considering only AMR gene information = -186 [95% CI: -281,-91]; model considering only taxonomic information = -151 [95% CI: -232,-69]). INTERPRETATION: Whilst our findings are exploratory and require validation, intermittent metagenomics of pooled samples could represent an effective approach for AMR surveillance and to predict population-level AMR in clinical isolates, complementary to ongoing development of laboratory infrastructures processing individual samples.

3.
Nat Commun ; 9(1): 5034, 2018 11 28.
Article in English | MEDLINE | ID: mdl-30487573

ABSTRACT

Some of the most common infectious diseases are caused by bacteria that naturally colonise humans asymptomatically. Combating these opportunistic pathogens requires an understanding of the traits that differentiate infecting strains from harmless relatives. Staphylococcus epidermidis is carried asymptomatically on the skin and mucous membranes of virtually all humans but is a major cause of nosocomial infection associated with invasive procedures. Here we address the underlying evolutionary mechanisms of opportunistic pathogenicity by combining pangenome-wide association studies and laboratory microbiology to compare S. epidermidis from bloodstream and wound infections and asymptomatic carriage. We identify 61 genes containing infection-associated genetic elements (k-mers) that correlate with in vitro variation in known pathogenicity traits (biofilm formation, cell toxicity, interleukin-8 production, methicillin resistance). Horizontal gene transfer spreads these elements, allowing divergent clones to cause infection. Finally, Random Forest model prediction of disease status (carriage vs. infection) identifies pathogenicity elements in 415 S. epidermidis isolates with 80% accuracy, demonstrating the potential for identifying risk genotypes pre-operatively.


Subject(s)
Skin Diseases/microbiology , Staphylococcal Infections/microbiology , Staphylococcus epidermidis/genetics , Staphylococcus epidermidis/pathogenicity , Genome, Bacterial/genetics , Genome-Wide Association Study , Genotype , Humans , Interleukin-8/metabolism
4.
Mol Ecol ; 27(7): 1524-1540, 2018 04.
Article in English | MEDLINE | ID: mdl-29509989

ABSTRACT

Bacterial plasmids can vary from small selfish genetic elements to large autonomous replicons that constitute a significant proportion of total cellular DNA. By conferring novel function to the cell, plasmids may facilitate evolution but their mobility may be opposed by co-evolutionary relationships with chromosomes or encouraged via the infectious sharing of genes encoding public goods. Here, we explore these hypotheses through large-scale examination of the association between plasmids and chromosomal DNA in the phenotypically diverse Bacillus cereus group. This complex group is rich in plasmids, many of which encode essential virulence factors (Cry toxins) that are known public goods. We characterized population genomic structure, gene content and plasmid distribution to investigate the role of mobile elements in diversification. We analysed coding sequence within the core and accessory genome of 190 B. cereus group isolates, including 23 novel sequences and genes from 410 reference plasmid genomes. While cry genes were widely distributed, those with invertebrate toxicity were predominantly associated with one sequence cluster (clade 2) and phenotypically defined Bacillus thuringiensis. Cry toxin plasmids in clade 2 showed evidence of recent horizontal transfer and variable gene content, a pattern of plasmid segregation consistent with transfer during infectious cooperation. Nevertheless, comparison between clades suggests that co-evolutionary interactions may drive association between plasmids and chromosomes and limit wider transfer of key virulence traits. Proliferation of successful plasmid and chromosome combinations is a feature of specialized pathogens with characteristic niches (Bacillus anthracis, B. thuringiensis) and has occurred multiple times in the B. cereus group.


Subject(s)
Bacillus cereus/genetics , Bacillus thuringiensis/genetics , Phylogeny , Plasmids/genetics , Alleles , Bacillus cereus/isolation & purification , Bacillus thuringiensis Toxins , Bacterial Proteins/genetics , Bacterial Toxins/metabolism , Chromosomes, Bacterial/genetics , Endotoxins/genetics , Genetic Variation , Genome, Bacterial , Hemolysin Proteins/genetics
5.
Genome Biol Evol ; 9(4): 830-842, 2017 04 01.
Article in English | MEDLINE | ID: mdl-28338786

ABSTRACT

Staphylococcus aureus are globally disseminated among farmed chickens causing skeletal muscle infections, dermatitis, and septicaemia. The emergence of poultry-associated lineages has involved zoonotic transmission from humans to chickens but questions remain about the specific adaptations that promote proliferation of chicken pathogens. We characterized genetic variation in a population of genome-sequenced S. aureus isolates of poultry and human origin. Genealogical analysis identified a dominant poultry-associated sequence cluster within the CC5 clonal complex. Poultry and human CC5 isolates were significantly distinct from each other and more recombination events were detected in the poultry isolates. We identified 44 recombination events in 33 genes along the branch extending to the poultry-specific CC5 cluster, and 47 genes were found more often in CC5 poultry isolates compared with those from humans. Many of these gene sequences were common in chicken isolates from other clonal complexes suggesting horizontal gene transfer among poultry associated lineages. Consistent with functional predictions for putative poultry-associated genes, poultry isolates showed enhanced growth at 42 °C and greater erythrocyte lysis on chicken blood agar in comparison with human isolates. By combining phenotype information with evolutionary analyses of staphylococcal genomes, we provide evidence of adaptation, following a human-to-poultry host transition. This has important implications for the emergence and dissemination of new pathogenic clones associated with modern agriculture.


Subject(s)
Adaptation, Physiological/genetics , Poultry Diseases/genetics , Staphylococcal Infections/genetics , Staphylococcus aureus/genetics , Animals , Chickens/genetics , Chickens/microbiology , Gene Transfer, Horizontal/genetics , Genome, Bacterial , Genotype , Humans , Poultry Diseases/microbiology , Poultry Diseases/transmission , Species Specificity , Staphylococcal Infections/microbiology , Staphylococcal Infections/transmission , Staphylococcus aureus/pathogenicity
6.
Stroke ; 48(3): 762-769, 2017 03.
Article in English | MEDLINE | ID: mdl-28193834

ABSTRACT

BACKGROUND AND PURPOSE: Circulating microRNAs (miRNAs) are emerging biomarkers for stroke because of their high stability in the bloodstream and association with pathophysiologic conditions. However, the circulating whole-genome miRNAs (miRNome) has not been characterized comprehensively in the acute phase of stroke. METHODS: We profiled the circulating miRNome in mouse models of acute ischemic and hemorrhagic stroke by next-generation sequencing. Stroke models were compared with sham-operated and naive mice to identify deregulated circulating miRNAs. Top-ranked miRNAs were validated and further characterized by quantitative reverse transcription polymerase chain reaction. RESULTS: We discovered 24 circulating miRNAs with an altered abundance in the circulation 3 hours after ischemia, whereas the circulating miRNome was not altered after intracerebral hemorrhage compared with sham-operated mice. Among the upregulated miRNAs in ischemia, the top-listed miR-1264/1298/448 cluster was strongly dependent on reperfusion in different ischemia models. A time course experiment revealed that the miR-1264/1298/448 cluster peaked in the circulation around 3 hours after reperfusion and gradually decreased thereafter. CONCLUSIONS: Alteration of the miRNome in the circulation is associated with cerebral ischemia/reperfusion, but not hemorrhage, suggesting a potential to serve as biomarkers for reperfusion in the acute phase. The pathophysiological role of reperfusion-inducible miR-1264/1298/448 cluster, which is located on chromosome X within the introns of the serotonin receptor HTR2C, requires further investigation.


Subject(s)
Brain Ischemia/genetics , MicroRNAs/blood , Multigene Family , Reperfusion Injury/genetics , Stroke/genetics , Animals , Biomarkers/analysis , Cerebral Hemorrhage/genetics , Genome-Wide Association Study , Male , Mice , Mice, Inbred C57BL , Reperfusion , Up-Regulation
7.
Nat Commun ; 8: 14048, 2017 01 16.
Article in English | MEDLINE | ID: mdl-28091603

ABSTRACT

Repo-Man is a protein phosphatase 1 (PP1) targeting subunit that regulates mitotic progression and chromatin remodelling. After mitosis, Repo-Man/PP1 remains associated with chromatin but its function in interphase is not known. Here we show that Repo-Man, via Nup153, is enriched on condensed chromatin at the nuclear periphery and at the edge of the nucleopore basket. Repo-Man/PP1 regulates the formation of heterochromatin, dephosphorylates H3S28 and it is necessary and sufficient for heterochromatin protein 1 binding and H3K27me3 recruitment. Using a novel proteogenomic approach, we show that Repo-Man is enriched at subtelomeric regions together with H2AZ and H3.3 and that depletion of Repo-Man alters the peripheral localization of a subset of these regions and alleviates repression of some polycomb telomeric genes. This study shows a role for a mitotic phosphatase in the regulation of the epigenetic landscape and gene expression in interphase.


Subject(s)
Carrier Proteins/metabolism , Cell Cycle Proteins/metabolism , Heterochromatin/metabolism , Interphase , Nuclear Proteins/metabolism , Carrier Proteins/genetics , Cell Cycle Proteins/genetics , Cell Line , Chromatin/genetics , Chromatin/metabolism , Chromatin Assembly and Disassembly , Heterochromatin/genetics , Histones/genetics , Histones/metabolism , Humans , Nuclear Proteins/genetics , Phosphorylation
8.
Genome Biol Evol ; 7(5): 1313-28, 2015 Apr 16.
Article in English | MEDLINE | ID: mdl-25888688

ABSTRACT

The opportunistic pathogens Staphylococcus aureus and Staphylococcus epidermidis represent major causes of severe nosocomial infection, and are associated with high levels of mortality and morbidity worldwide. These species are both common commensals on the human skin and in the nasal pharynx, but are genetically distinct, differing at 24% average nucleotide divergence in 1,478 core genes. To better understand the genome dynamics of these ecologically similar staphylococcal species, we carried out a comparative analysis of 324 S. aureus and S. epidermidis genomes, including 83 novel S. epidermidis sequences. A reference pan-genome approach and whole genome multilocus-sequence typing revealed that around half of the genome was shared between the species. Based on a BratNextGen analysis, homologous recombination was found to have impacted on 40% of the core genes in S. epidermidis, but on only 24% of the core genes in S. aureus. Homologous recombination between the species is rare, with a maximum of nine gene alleles shared between any two S. epidermidis and S. aureus isolates. In contrast, there was considerable interspecies admixture of mobile elements, in particular genes associated with the SaPIn1 pathogenicity island, metal detoxification, and the methicillin-resistance island SCCmec. Our data and analysis provide a context for considering the nature of recombinational boundaries between S. aureus and S. epidermidis and, the selective forces that influence realized recombination between these species.


Subject(s)
Gene Transfer, Horizontal , Staphylococcus aureus/genetics , Staphylococcus epidermidis/genetics , Ecological and Environmental Phenomena , Evolution, Molecular , Genes, Fungal , Genetic Variation , Genome, Fungal , Homologous Recombination
9.
BMC Biotechnol ; 13: 104, 2013 Nov 20.
Article in English | MEDLINE | ID: mdl-24256843

ABSTRACT

BACKGROUND: The Nextera protocol, which utilises a transposome based approach to create libraries for Illumina sequencing, requires pure DNA template, an accurate assessment of input concentration and a column clean-up that limits its applicability for high-throughput sample preparation. We addressed the identified limitations to develop a robust workflow that supports both rapid and high-throughput projects also reducing reagent costs. RESULTS: We show that an initial bead-based normalisation step can remove the need for quantification and improves sample purity. A 75% cost reduction was achieved with a low-volume modified protocol which was tested over genomes with different GC content to demonstrate its robustness. Finally we developed a custom set of index tags and primers which increase the number of samples that can simultaneously be sequenced on a single lane of an Illumina instrument. CONCLUSIONS: We addressed the bottlenecks of Nextera library construction to produce a modified protocol which harnesses the full power of the Nextera kit and allows the reproducible construction of libraries on a high-throughput scale reducing the associated cost of the kit.


Subject(s)
DNA Primers/isolation & purification , Gene Library , High-Throughput Nucleotide Sequencing/methods , Automation, Laboratory , Clostridioides difficile/genetics , DNA Primers/genetics , Sequence Analysis, DNA/methods , Workflow
10.
PLoS Genet ; 8(12): e1003074, 2012.
Article in English | MEDLINE | ID: mdl-23236289

ABSTRACT

ß-III spectrin is present in the brain and is known to be important in the function of the cerebellum. Heterozygous mutations in SPTBN2, the gene encoding ß-III spectrin, cause Spinocerebellar Ataxia Type 5 (SCA5), an adult-onset, slowly progressive, autosomal-dominant pure cerebellar ataxia. SCA5 is sometimes known as "Lincoln ataxia," because the largest known family is descended from relatives of the United States President Abraham Lincoln. Using targeted capture and next-generation sequencing, we identified a homozygous stop codon in SPTBN2 in a consanguineous family in which childhood developmental ataxia co-segregates with cognitive impairment. The cognitive impairment could result from mutations in a second gene, but further analysis using whole-genome sequencing combined with SNP array analysis did not reveal any evidence of other mutations. We also examined a mouse knockout of ß-III spectrin in which ataxia and progressive degeneration of cerebellar Purkinje cells has been previously reported and found morphological abnormalities in neurons from prefrontal cortex and deficits in object recognition tasks, consistent with the human cognitive phenotype. These data provide the first evidence that ß-III spectrin plays an important role in cortical brain development and cognition, in addition to its function in the cerebellum; and we conclude that cognitive impairment is an integral part of this novel recessive ataxic syndrome, Spectrin-associated Autosomal Recessive Cerebellar Ataxia type 1 (SPARCA1). In addition, the identification of SPARCA1 and normal heterozygous carriers of the stop codon in SPTBN2 provides insights into the mechanism of molecular dominance in SCA5 and demonstrates that the cell-specific repertoire of spectrin subunits underlies a novel group of disorders, the neuronal spectrinopathies, which includes SCA5, SPARCA1, and a form of West syndrome.


Subject(s)
Cerebellum , Spectrin/genetics , Spinocerebellar Ataxias , Adult , Animals , Cerebellum/growth & development , Cerebellum/pathology , Chromosome Mapping , Cognition Disorders/genetics , Humans , Mice , Mice, Knockout , Mutation , Neurons/metabolism , Neurons/pathology , Purkinje Cells/pathology , Spinocerebellar Ataxias/genetics , Spinocerebellar Ataxias/physiopathology
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