bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of Equine Herpesvirus 1 glycoprotein pseudotyped lentiviral particles for the development of serological tests and assessment of lyophilisation for transport and storage
Authors: Genova Cecilia Di , Sutton Gabrielle , Paillot Romain , Temperton Nigel , Pronost Stéphane , Scott Simon D
Published: May 2022

Equine herpesviruses (EHVs) are enveloped DNA viruses predominantly infecting members of the Equidae family. EHVs primarily cause respiratory disease, however EHV-1 can produce cases of a neurological disease, abortion and neonatal death. Thus, these viruses represent a welfare issue for the equine industry and scientific focus for researchers. EHV-1 exhibits a complex array of 12 glycoproteins on its surface envelope, but it is unclear precisely which are important for virus cell entry and the role of each in host immune response. In order to investigate the contribution of these glycoproteins, pseudotype viruses (PVs) could provide a useful study tool. We have successfully generated functional EHV-1 pseudotyped lentiviruses bearing four glycoproteins, gB, gD, gH and gL (sequences derived from an aborted foetus during a large EHV1 outbreak strain in Normandy, France). PVs were employed in a pseudotype virus neutralisation test (PVNT) to measure levels of specific neutralising antibodies serum samples (n=52) taken longitudinally from experimentally infected ponies, compared with uninfected controls.

PVs routinely require -80oC for long term storage and a dry ice cold-chain during transport which can impede dissemination and utilisation in other laboratories. Consequently, we further investigated whether freeze-drying (lyophilisation) of EHV-1 PV could address this issue. PVs were lyophilised and pellets either reconstituted immediately or stored under various temperature conditions, sampling at different timepoints. The recovery and functionality of these lyophilised PVs was compared with standard frozen aliquots in titration and neutralisation tests.
Potentials of Breast Milk Antibodies as a Therapeutic for COVID-19
Authors: Nnaemeka Victory
Published: May 2022

Since the explosion of pneumonia-like symptoms in the province of Hubei, Wuhan in December 2019 over 200 countries have gotten a share of this disease caused by the novel coronavirus disease 2019 (COVID-19). Till date, there exists no modest therapeutic agent to combat this virus. Antibodies in the breast milk of convalescent lactating mothers could be the silver bullet that would deflate the ballooning morbidity and mortality rate caused by the COVID-19 pandemic. Coupled with the fact that breast milk contains a very high amount of Immunoglobulin A which has a desirable higher in vivo stability than other antibodies. This novel approach of purifying antibodies from the breast milk of convalescent lactating mothers is a non-invasive technique relative to the conventional method of using convalescent plasma which had proven effective for generating passive immunity against the seasonal flu. Purified Immunoglobulins would be obtained by adding an equal volume of ammonium sulphate solution to the breast milk sample to induce a lyotropic effect and thereafter passing the partially purified solution through a column chromatographic system impregnated with a Jaclin –lectin, Protein A, L and G. Neutralizing antibodies would by assayed using the Enzyme-Linked Immunosorbent Assay technique. Various statistical tools will be used to analyze a double-blinded randomized clinical trials to ascertain the efficacy of the purified antibodies as it is expected to have clear cut effectiveness over the control and potentially become the invaluable in containing the pandemic.
Embedding 21st century employability into assessment and feedback practice through a student-staff partnership
Authors: Veitch Nicola , Mcgregor Anna , Stubbs Fiona , Broom Miranda , Zainudden Dzachary
Published: May 2022

Although commonly thought to be only a measure of academic performance, assessments can also provide students with an opportunity to apply skills and knowledge acquired at university into written literacies that prepare them for the transition into prospective careers. Within a Level 2 Microbiology and Immunology course, students struggled to engage with standalone timetabled careers-related sessions, yet they showed enthusiasm when employability was embedded into assessments. A staff-student partnership project explored these issues, with the overall aim of understanding how to effectively embed employability skills into assessment and feedback, which supports the theme of supporting students to position themselves for the future.

Through student-run focus groups, this project investigated the reasons for low student engagement with the timetabled employability session and used student views to develop digital initiatives that could be applied to assessment and feedback practice with an emphasis on developing 21st-century competencies. These initiatives were then implemented as pre-session self-directed activities, which helped students link course feedback with employment skills and future career planning, followed by a newly developed in-class reflective feedback session that allowed students time to consider what skills they have developed and make links with future careers. Project evaluation was conducted using a quantitative survey of students involved.

This project aims to make feedback more meaningful and better valued by students. The approaches were designed in partnership with former students from the course, this project possesses the unique ability to deliver a genuine student voice both on employability concerns and the role of assessment.
Genomic epidemiology and temperature dependency of hypermucoviscous Klebsiella pneumoniae in Japan
Authors: Le Mi Nguyen-Tra , Kayama Shizuo , Wyres Kelly L. , Yu Liansheng , Hisatsune Junzo , Suzuki Masato , Yahara Koji , Terachi Tsuneko , Sawa Kana , Takahashi Shin , Okuhara Toshihiko , Kohama Kunihiko , Holt Kathryn E. , Mizutani Tetsu , Ohge Hiroki , Sugai Motoyuki
Published: May 2022

Klebsiella pneumoniae

(Kp) has emerged as a global life-threatening pathogen owing to its multidrug resistance and hypervirulence phenotype. Several fatal outbreaks of carbapenem-resistant hypervirulent Kp have been reported recently. Hypermucoviscosity (HMV) is a phenotype commonly associated with hypervirulence of Kp, which is usually regulated by rmpA or rmpA2 (regulators of the mucoid phenotype). Here, we found that temperature was important in the HMV phenotype of Kp, and the impact of temperature on HMV was not uniform among strains. We investigated the HMV phenotype at 37 °C and room temperature (20–25 °C) in 170 clinically isolated hypermucoviscous Kp strains in Japan and analysed the association between the HMV phenotype, virulence genes and antimicrobial resistance (AMR) genes. String length distribution at different temperatures was correlated with the genomic population of Kp. The strains carrying rmpA/rmpA2 frequently showed the HMV phenotype at 37 °C, while the strains negative for these genes tended to show the HMV phenotype at room temperature. Hypervirulent Kp clusters carrying rmpA/rmpA2 without extended-spectrum beta-lactamases (ESBL)/carbapenemases produced higher string lengths at 37 °C than at room temperature, and were mostly isolated from the respiratory tract. Other HMV strains showed distinct characteristics of not carrying rmpA/rmpA2 but were positive for ESBL/carbapenemases, with a higher string length at room temperature than at 37 °C, and were frequently isolated from bloodstream infections. In total, 21 (13.5 %) HMV isolates carried ESBL and carbapenemases, among which five isolates were carbapenem-resistant hypervirulent Kp with a pLVPK-like plasmid (an epidemic virulence plasmid) and a pKPI-6-like plasmid (an epidemic bla
IMP-6-bearing plasmid in Japan), suggesting the convergence of worldwide hypervirulence and epidemic AMR in Japan.
Target-enrichment sequencing yields valuable genomic data for challenging-to-culture bacteria of public health importance
Authors: Dennis Tristan P. W. , Mable Barbara K. , Brunelle Brian , Devault Alison , Carter Ryan W. , Ling Clare L. , Mmbaga Blandina T. , Halliday Jo E. B. , Oravcova Katarina , Forde Taya L.
Published: May 2022

Genomic data contribute invaluable information to the epidemiological investigation of pathogens of public health importance. However, whole-genome sequencing (WGS) of bacteria typically relies on culture, which represents a major hurdle for generating such data for a wide range of species for which culture is challenging. In this study, we assessed the use of culture-free target-enrichment sequencing as a method for generating genomic data for two bacterial species: (1)Bacillus anthracis,which causes anthrax in both people and animals and whose culture requires high-level containment facilities; and (2)Mycoplasma amphoriforme, a fastidious emerging human respiratory pathogen. We obtained high-quality genomic data for both species directly from clinical samples, with sufficient coverage (>15×) for confident variant calling over at least 80% of the baited genomes for over two thirds of the samples tested. Higher qPCR cycle threshold (Ct) values (indicative of lower pathogen concentrations in the samples), pooling libraries prior to capture, and lower captured library concentration were all statistically associated with lower capture efficiency. TheCtvalue had the highest predictive value, explaining 52 % of the variation in capture efficiency. Samples withCtvalues ≤30 were over six times more likely to achieve the threshold coverage than those with aCt> 30. We conclude that target-enrichment sequencing provides a valuable alternative to standard WGS following bacterial culture and creates opportunities for an improved understanding of the epidemiology and evolution of many clinically important pathogens for which culture is challenging.
The effect of GLP-1RA exenatide on Idiopathic Intracranial Hypertension: Randomised Clinical Trial
Authors: Mitchell James L. , Lyons Hannah S. , Walker Jessica K. , Yiangou Andreas , Grech Olivia , Alimajstorovic Zerin , Greig Nigel H. , Li Yazhou , Tsermoulas Georgios , Brock Kristian , Mollan Susan P. , Sinclair Alexandra J.
Published: May 2022

Therapeutics to reduce intracranial pressure are an unmet need. Pre-clinical data has demonstrated a novel strategy to lower intracranial pressure using glucagon-like peptide-1 receptor signaling.

Here, we translate these findings into patients by conducting a randomized, placebo controlled, double-blind trial to assess the effect of exenatide, a glucagon-like peptide-1 receptor agonist, on intracranial pressure in idiopathic intracranial hypertension. Telemetric intracranial pressure catheters enabled long-term intracranial pressure monitoring. The trial enrolled adult women with active idiopathic intracranial hypertension (intracranial pressure >25 cmCSF and papilloedema) who receive subcutaneous exenatide or placebo. The three primary outcome measures were intracranial pressure at 2.5 hours, 24 hours and 12 weeks and alpha set a priori at less than 0.1.

Among the 16 women recruited, 15 completed the study (mean age 28 ± 9, body mass index 38.1 ± 6.2 kg/m2, intracranial pressure 30.6 ± 5.1 cmCSF). Exenatide significantly and meaningfully lowered intracranial pressure at 2.5 hours -5.7 ± 2.9 cmCSF (p=0.048); 24 hours of -6.4 ± 2.9 cmCSF (p=0.030); and 12 weeks -5.6 ± 3.0 cmCSF (p=0.058). No serious safety signals were noted.

This data provides confidence to proceed to a phase 3 trial in idiopathic intracranial hypertension and highlights the potential to utilise glucagon-like peptide-1 receptor agonist in other conditions characterised by raised intracranial pressure.
Men’s preconception health and the social determinants of health: What are we missing?
Authors: Anakwe Adaobi , Xian Hong , BeLue Rhonda , Xaverius Pamela
Published: May 2022

Background

Life course perspectives suggest that optimizing men’s health before conception is requisite to equitably improve population health, an area of increasing public health focus. Although scholarship on the social determinants of health (SDOH) suggests that men’s health and health behaviors do not occur in a vacuum, preconception health studies have not explicitly examined how these factors influence men’s preconception health.

Objective

To identify latent classes of men’s preconception health and the role of the SDOHs in predicting class membership.

Methods

Pooled data from the 2011-2019 male file of the National Survey of Family Growth were analyzed (n= 10,223). Latent class analysis was used to identify distinct classes of men’s preconception health. Eight manifest variables were used to fit latent class models. A classify-analyze approach was subsequently used to create a preconception health phenotype (PhP) outcome variable. SDOHs (exposure variable) were assessed in four domains (residential context, health access, socioeconomic status, and sociocultural context) to predict class membership. Survey weighted multinomial regression models were fitted to examine the association between the exposure and the outcome.

Results

Three unique PhPs were identified (lowest risk (69%), substance users (22.9%), and sexual risk-takers (8.1%) (SRT)) from the LCA model. Health access, socioeconomic status, and sociocultural contexts were significant predictors of class membership but not residential context. Sexual risk takers were more likely to be uninsured (aOR: 1.25, 95% CI 1.02, 1.52), college-educated (aOR: 1.94 95% CI: 1.34, 2.79), and non-Hispanic Black (aOR: 1.99 95% CI: 1.55, 2.54) while substance users were more likely to have unstable employment (aOR: 1.23 95% CI:1.04, 1.45) and have a high school degree or higher (aOR 1.48 95% CI: 1.15, 1.90) than men in the lowest risk category.

Conclusion

Findings suggest that social determinants may impact men’s preconception health in ways that are not conventionally understood and raises important questions about how preconception health interventions should be created, tailored, and/or retooled. Specifically, studies that examine the sociocultural and political contexts underpinning the relationship between social class, masculinity, and men’s preconception health are needed to provide nuanced insights on factors that shape these outcomes.
SMAD4 suppresses colitis-associated carcinoma through inhibition of CCL20/CCR6-mediated inflammation
Authors: Hanna David N. , Smith Paula Marincola , Novitskiy Sergey V. , Washington M. Kay , Zi Jinghuan , Weaver Connie J. , Hamaamen Jalal A. , Lewis Keeli B. , Zhu Jing , Yang Jing , Liu Qi , Beauchamp R. Daniel , Means Anna L.
Published: May 2022

Background & Aims

Chronic inflammation in the colon is a predisposing factor for colon cancer. We previously reported that colon epithelial cell silencing of Smad4, the central downstream mediator of TGFβ family signaling, increased epithelial expression of inflammatory genes, including the chemokine CCL20, and increased susceptibility to colitis-associated cancer. Here, we examine the role of the chemokine/receptor pair CCL20/CCR6 in mediating colitis-associated colon carcinogenesis induced by SMAD4 loss.

Methods

Mice with conditional, epithelial-specific Smad4 loss with and without germline deletion of the Ccr6 gene were subjected to three rounds of dextran sodium sulfate and followed for up to 3 months. Tumors were quantified histologically, and immune cell populations were analyzed by flow cytometry and immunostaining.

Results

In humans, SMAD4 expression inversely correlated with CCL20 expression. Smad4 loss in mouse colon epithelium led to enlarged gut-associated lymphoid tissues and recruitment of specific immune cell subsets to the mouse colon epithelium and underlying stroma, particularly Treg, Th17, and dendritic cells. Loss of CCR6 abrogated these immune responses and significantly reduced the incidence of colitis-associated tumors observed with loss of SMAD4 alone.

Conclusions

Regulation of mucosal inflammation is a critical role of SMAD4 signaling within the colon epithelium and central to its tumor suppressor function in the colon. A key downstream node in this regulation is suppression of CCL20 signaling by the epithelium to CCR6 in immune cells. Loss of SMAD4 in the colon epithelium increases CCL20 expression and chemoattraction of CCR6+ immune cells, contributing to greater susceptibility to colon cancer.
γ-Protocadherins control synapse formation and peripheral branching of touch sensory neurons
Authors: Meltzer Shan , Comeau Katelyn , Chirila Anda , Osei-Asante Emmanuella , DeLisle Michelle , Zhang Qiyu , Kalish Brian T. , Tasnim Aniqa , Huey Erica , Fuller Leah C. , Flaherty Erin K. , Lefebvre Julie L. , Maniatis Tom , Garrett Andrew M. , Weiner Joshua A. , Ginty David D.
Published: May 2022

Light touch sensation begins with activation of low-threshold mechanoreceptor (LTMR) endings in the skin and propagation of their signals to the spinal cord and brainstem. We found that the clustered protocadherin gamma (Pcdhg) gene locus, which encodes 22 cell-surface homophilic binding proteins, is required in somatosensory neurons for normal behavioral reactivity to a range of tactile stimuli. Developmentally, distinct Pcdhg isoforms mediate LTMR synapse formation through neuron-neuron interactions and peripheral axonal branching through neuron-glia interactions. The Pcdhgc3 isoform mediates homophilic interactions between sensory axons and spinal cord neurons to promote synapse formationin vivo, and is sufficient to induce postsynaptic specializationsin vitro. Moreover, loss of Pcdhgs and somatosensory synaptic inputs to the dorsal horn lead to fewer corticospinal synapses onto dorsal horn neurons. These findings reveal essential roles for Pcdhg isoform diversity in somatosensory neuron synapse formation, peripheral axonal branching, and step-wise assembly of central mechanosensory circuitry.
Variation in glutamate and GABA genes and their association with brain structure and chemistry in autism
Authors: Naaijen Jilly , Arenella Martina , Zöllner Helge J , Puts Nicolaas A , Lythgoe David J , Brandeis Daniel , Durston Sarah , Poelmans Geert , Ruisch I Hyun , Buitelaar Jan K
Published: May 2022

The excitatory/inhibitory (E/I) imbalance hypothesis posits that an imbalance between glutamatergic and GABAergic neurotransmission contributes to autism symptomatology. Whether this is due to altered GABAergic or glutamatergic functioning, or both, remains largely unknown. We integrated genetic, brain structure and brain chemistry data to investigate the relationship between E/I genetic variation and expression, glutamate concentrations and cortical thickness (CT). Participants (60 autism and 104 neurotypical controls, aged 8-13 years) underwent magnetic resonance imaging and spectroscopy for glutamate quantification in the anterior cingulate cortex (ACC) and left dorsal striatum. Genetic involvement in these regional glutamate concentration levels was investigated using competitive gene-set association and polygenic scores (PGS). Further, glutamate as well as GABA gene-set expression profiles were investigated in relation to CT. Aggregated genetic variation in the glutamate gene-set was associated with ACC but not striatal glutamate concentrations. PGS analysis, however, showed a genome-wide PGS for autism to be predictive of striatal but not ACC glutamate levels. Expression profiles of GABAergic-but not glutamatergic genes were associated with differences in cortical thickness between groups. This study showed differential involvement of aggregated glutamatergic and GABAergic genetic variation in brain structure and chemistry in autism, which suggests regional variability in E/I imbalance.
Genetic characterisation of the Theileria annulata cytochrome b locus and its impact on buparvaquone resistance in ruminants
Authors: Ali Qasim , Zahid Osama , Mhadhbi Moez , Jones Ben , Darghouth Mohamed Aziz , Raynes George , Afshan Kiran , Birtles Richard , Sargison Neil D. , Betson Martha , Chaudhry Umer
Published: May 2022

Control of tropical theileriosis depends on the use of a single drug, buparvaquone, the efficacy of which is compromised by the emergence of resistance. The present study was undertaken to improve understanding of the role of mutations conferring buparvaquone resistance in Theileria annulata, and the effects of selection pressures on their emergence and spread. First, we investigated genetic characteristics of the cytochrome b locus associated with buparvaquone resistance in 10 susceptible and 7 resistant T. annulata isolates. The 129G (GGC) mutation was found in the Q01 binding pocket and 253S (TCT) and 262S (TCA) mutations were identified within the Q02 binding pocket. Next, we examined field isolates and identified cytochrome b mutations 129G (GGC), 253S (TCT) and 262S (TCA) in 21/75 buffalo-derived and 19/119 cattle-derived T. annulata isolates, providing evidence of positive selection pressure. Both hard and soft selective sweeps were identified, with striking differences between isolates. For example, 19 buffalo-derived and 7 cattle-derived isolates contained 129G (GGC) and 253S (TCT) resistance haplotypes at a high frequency, implying the emergence of resistance by a single mutation. Two buffalo-derived and 11 cattle-derived isolates contained equally high frequencies of 129G (GGC), 253S (TCT), 129G (GGC)/253S (TCT) and 262S (TCA) resistance haplotypes, implying the emergence of resistance by pre-existing and or recurrent mutations. Phylogenetic analysis further revealed that 9 and 21 unique haplotypes in buffalo and cattle-derived isolates were present in a single lineage, suggesting a single origin. We propose that animal migration between farms is an important factor in the spread of buparvaquone resistance in endemic regions of Pakistan. The overall outcomes will be useful in understanding how drug resistance emerges and spreads, and this information will help design strategies to optimise the use and lifespan of the single most drug use to control tropical theileriosis.
De novo lipogenesis fuels adipocyte autophagosome membrane dynamics
Authors: Rowland Leslie A. , Guilherme Adilson , Henriques Felipe , DiMarzio Chloe , Wetoska Nicole , Kelly Mark , Reddig Keith , Hendricks Gregory , Pan Meixia , Han Xianlin , Ilkayeva Olga R. , Newgard Christopher B. , Czech Michael P.
Published: May 2022

Autophagy is a homeostatic degradative process for cell components that enables stress resilience and can determine cellular fate and function. However, lipid sources for the rapid membrane expansions of autophagosomes, the workhorses of autophagy, are poorly understood. Here, we identify de novo lipogenesis (DNL) as a critical source of fatty acids (FA) to fuel autophagosome dynamics in adipocytes. Adipocyte fatty acid synthase (Fasn) deficiency markedly impairs autophagy, evident by autophagosome accumulation, and severely compromises degradation of the autophagic substrate p62. Autophagy dependence on FA produced by Fasn is not fully alleviated by exogenous FA in cultured adipocytes even though lipid droplet size is restored. Imaging studies reveal that Fasn colocalizes with nascent autophagosomes, while loss of Fasn decreases certain membrane phosphoinositides known to be required for autophagosome assembly. Together, our studies highlight a newly appreciated function for adipocyte DNL in autophagosome membrane formation and provide evidence that localized FA synthesis contributes to autophagosome dynamics.
Ferric reductase-related proteins mediate fungal heme acquisition
Authors: Roy Udita , Yaish Shir , Weissman Ziva , Pinsky Mariel , Dey Sunanda , Horev Guy , Kornitzer Daniel
Published: May 2022

Heme can serve as iron source in many environments, including the iron-poor animal host environment. The fungal pathobiont Candida albicans expresses a family of extracellular CFEM hemophores that capture heme from host proteins and transfer it across the cell wall to the cell membrane, to be endocytosed and utilized as heme or iron source. Here we identified Frp1 and Frp2, two ferric reductase (FRE)-related proteins that lack an extracellular N-terminal substrate-binding domain, as being required for hemoglobin heme utilization and for sensitivity to toxic heme analogs. Frp1/2 redistribute from the ER to the plasma membrane in the presence of hemoglobin, consistent with a direct role in heme trafficking. Expression of Frp1 with the CFEM hemophore Pga7 can promote heme utilization in Saccharomyces cerevisiae as well, confirming the functional interaction between these proteins. Sequence and structure comparison reveals that the CFEM hemophores are related to the FRE substrate-binding domain that is missing in Frp1/2. We conclude that Frp1/2 and the CFEM hemophores form a functional complex that evolved from ferric reductases to enable extracellular heme uptake.
Aurora A and cortical flows promote polarization and cytokinesis by inducing asymmetric ECT-2 accumulation
Authors: Longhini Katrina M , Glotzer Michael
Published: May 2022

In the early C. elegans embryo, cell polarization and cytokinesis are interrelated yet distinct processes. Here, we sought to understand a poorly understood aspect of cleavage furrow positioning. Early C. elegans embryos deficient in the cytokinetic regulator centralspindlin form furrows, due to an inhibitory activity that depends on aster positioning relative to the polar cortices. Here, we show polar relaxation is associated with depletion of cortical ECT-2, a RhoGEF, specifically at the posterior cortex. Asymmetric ECT-2 accumulation requires intact centrosomes, Aurora A (AIR-1), and myosin-dependent cortical flows. Within a localization competent ECT-2 fragment, we identified three putative phospho-acceptor sites in the PH domain of ECT-2 that render ECT-2 responsive to inhibition by AIR-1. During both polarization and cytokinesis, our results suggest that centrosomal AIR-1 breaks symmetry via ECT-2 phosphorylation; this local inhibition of ECT-2 is amplified by myosin-driven flows that generate regional ECT-2 asymmetry. Together, these mechanisms cooperate to induce polarized assembly of cortical myosin, contributing to both embryo polarization and cytokinesis.
Tissue libraries enable rapid determination of conditions that preserve antibody labeling in cleared mouse and human tissue
Authors: Zwang Theodore J. , Bennett Rachel E. , Lysandrou Maria , Woost Benjamin , Zhang Anqi , Lieber Charles M. , Richardson Douglas S. , Hyman Bradley T.
Published: May 2022

Difficulty achieving complete, specific, and homogenous staining is a major bottleneck preventing the widespread use of tissue clearing techniques to image large volumes of human tissue. In this manuscript, we describe a procedure to rapidly design immunostaining protocols for antibody labeling of cleared brain tissue. We prepared libraries of .5-1.0 mm thick tissue sections that are fixed, pre-treated, and cleared via similar, but different procedures to optimize staining conditions for a panel of antibodies. Results from a library of mouse tissue correlate well with results from a similarly prepared library of human brain tissue, suggesting mouse tissue is an adequate substitute for protocol optimization. These data show that procedural differences do not influence every antibody-antigen pair in the same way, and minor changes can have deleterious effects, therefore, optimization should be conducted for each target. The approach outlined here will help guide researchers to successfully label a variety of targets, thus removing a major hurdle to accessing the rich 3D information available in large, cleared human tissue volumes.
Oral cholestyramine prevents enrichment of diverse daptomycin-resistance mutations in intestinal Enterococcus faecium
Authors: Morley Valerie J. , Sim Derek G. , Penkevich Aline , Woods Robert J. , Read Andrew F.
Published: May 2022

Background and Objectives

Previously, we showed proof-of-concept in a mouse model that oral administration of cholestyramine prevented enrichment of daptomycin-resistant Enterococcus faecium in the gastrointestinal (GI) tract during daptomycin therapy. Cholestyramine binds daptomycin in the gut, which removes daptomycin selection pressure and so prevents the enrichment of resistant clones. Here, we investigated two open questions related to this approach: 1) can cholestyramine prevent the enrichment of diverse daptomycin mutations emerging de novo in the gut? 2) how does the timing of cholestyramine administration impact its ability to suppress resistance?

Methodology

Mice with GI E. faecium were treated with daptomycin with or without cholestyramine, and E. faecium was cultured from feces to measure changes in daptomycin susceptibility. A subset of clones was sequenced to investigate the genomic basis of daptomycin resistance.

Results

Cholestyramine prevented the enrichment of diverse resistance mutations that emerged de novo in daptomycin-treated mice. Whole-genome sequencing revealed that resistance emerged through multiple genetic pathways, with most candidate resistance mutations observed in the clsA gene. Additionally, we observed that cholestyramine was most effective when administration started prior to the first dose of daptomycin. However, beginning cholestyramine after the first daptomycin dose reduced the frequency of resistant E. faecium compared to not using cholestyramine at all.

Conclusions and Implications

Cholestyramine prevented the enrichment of diverse daptomycin-resistance mutations in intestinal E. faecium populations during daptomycin treatment, and it is a promising tool for managing transmission of daptomycin-resistant E. faecium.
Uncoupling from transcription protects polyadenylation site cleavage from inhibition by DNA damage
Authors: Sfaxi Rym , Biswas Biswendu , Boldina Galina , Cadix Mandy , Servant Nicolas , Chen Huimin , Larson Daniel R. , Dutertre Martin , Robert Caroline , Vagner Stéphan
Published: May 2022

Pre-mRNA 3’-end processing by cleavage and polyadenylation (CPA) is a nuclear process in which RNA polymerase II (Pol II) transcripts are cleaved at the polyadenylation site (PAS cleavage) before addition of a poly(A) tail. While PAS cleavage is usually coupled to transcription termination, for some pre-mRNAs it occurs post-transcriptionally, i.e. after pre-mRNA release from chromatin to nucleoplasm through a downstream co-transcriptional cleavage (CoTC) event. DNA-damaging agents such as ultraviolet-C (UV) irradiation trigger rapid shutdown of pre-mRNA 3’-end processing. However, specific compensatory mechanisms exist to ensure efficient 3’-end processing for some pre-mRNAs encoding proteins involved in the DNA damage response (DDR), such as the p53 tumor suppressor protein. Here, we show that PAS cleavage of the p53 pre-mRNA occurs in part post-transcriptionally, in a PCF11-independent manner, in the nucleoplasm, following a CoTC-type event. Upon UV-irradiation, cells with an engineered deletion of the p53 CoTC site exhibit impaired 3’-end processing of the p53 pre-mRNA, decreased mRNA and protein levels of p53 and its transcriptional target, p21, and altered cell cycle progression. Finally, using a transcriptome-wide analysis of PAS cleavage, we identified additional-including DDR related-pre-mRNAs whose PAS cleavage is maintained in response to UV and occurs post-transcriptionally. These findings indicate that CoTC-type cleavage of pre-mRNAs, followed by PAS cleavage in the nucleoplasm, allows specific pre-mRNAs to escape 3’-end processing inhibition in response to UV-induced DNA damage.
Representing linguistic communicative goals in the premotor cortex
Authors: Chang Wenshuo , Wang Lihui , Yang Ruolin , Wang Xingchao , Gao Zhixian , Zhou Xiaolin
Published: May 2022

Linguistic communication is often regarded as an action conveying the speaker’s communicative goal to the addressee. With both correlational (an fMRI study) and causal (a lesion study) evidence, we demonstrated that communicative goals are represented in human premotor cortex. Participants read scripts each containing a sentence said by the speaker with a goal of either a promise, a request, or a reply. The fMRI results showed that the premotor cortex represented more information on communicative goals than the perisylvian language regions. The lesion study results showed that, relative to healthy controls, the understanding of communicative goals was impaired in patients with lesions in the premotor cortex, whereas no reliable difference between the healthy controls and lesion controls. These findings convergently suggest that the premotor cortex is crucial for representing the goals conveyed by language, supporting the theoretical view that linguistic communication can be seen as a goal-directed action.
Morphodynamic Atlas for Drosophila Development
Authors: Mitchell Noah P , Lefebvre Matthew F , Jain-Sharma Vishank , Claussen Nikolas , Raich Marion K , Gustafson Hannah J , Bausch Andreas R , Streichan Sebastian J
Published: May 2022

During morphogenesis, diverse cell-scale and tissue-scale processes couple to dynamically sculpt organs. In this coupling, genetic expression patterns and biochemical signals regulate and respond to mechanical deformations to ensure reproducible and robust changes in tissue geometry. A long-standing approach to characterize these interactions has been the construction of expression atlases, and these atlases have necessarily relied on fixed snapshots of embryogenesis. Addressing how expression profiles relate to tissue dynamics, however, requires a scheme for spatiotemporal registration across different classes of data that incorporates both live samples and fixed datasets. Here, we construct a morphodynamic atlas that unifies fixed and live datasets – from gene expression profiles to cytoskeletal components – into a single, morphological consensus timeline. This resource and our computational approach to global alignment facilitate hypothesis testing using quantitative comparison of data both within and across ensembles, with resolution in both space and time to relate genes to tissue rearrangement, cell behaviors, and out-of-plane motion. Examination of embryo kinematics reveals stages in which tissue flow patterns are quasi-stationary, arranged as a sequence of ‘morphodynamic modules’. Temperature perturbations tune the duration of one such module – during body axis elongation – according to a simple, parameter-free scaling in which the total integrated tissue deformation is achieved at a temperature-dependent rate. By extending our approach to visceral organ formation during later stages of embryogenesis, we highlight how morphodynamic atlases can incorporate complex shapes deforming in 3D. In this context, morphodynamic modules are reflected in some, but not all, measures of tissue motion. Our approach and the resulting atlas opens up the ability to quantitatively test hypotheses with resolution in both space and time, relating genes to tissue rearrangement, cell behaviors, and organ motion.
Population History and Genome Wide Association Studies of Birth Weight in a Native High Altitude Ladakhi Population
Authors: Bhandari Sushil , Dolma Padma , Mukerji Mitali , Prasher Bhavana , Montgomery Hugh , Kular Dalvir , Jain Vandana , Dadhwal Vatsla , Williams David J , Bhattacharyaa Aniket , Gilbert Edmund , Cavalleri Gianpiero L , Hillman Sara L
Published: May 2022

Pathological low birth weight due to fetal growth restriction (FGR)is an important predictor of adverse obstetric and neonatal outcomes. It is more common amongst native lowlanders when gestating in the hypoxic environment of high altitude, whilst populations who have resided at high altitude for many generations are relatively protected. Genetic study of pregnant populations at high altitude permits exploration of the role of hypoxic in FGR pathogenesis, and perhaps of FGR pathogenesis more broadly.

We studied the umbilical cord blood DNA of 316 neonates born to pregnant women managed at the Sonam Norboo Memorial Hospital, Ladakh (altitude 3540m) between February 2017-January 2019. Principal component, admixture and genome wide association studies (GWAS) were applied to dense single nucleotide polymorphism (SNP) genetic data, to explore ancestry and genetic predictors of low birth weight.

Our findings support Tibetan ancestry in the Ladakhi population, with subsequent admixture with neighboring Indo-Aryan populations. Fetal growth protection was evident in Ladakhi neonates. Although no variants achieved genome wide significance, we observed nominal association of seven variants across genes (ZBTB38, ZFP36L2, HMGA2, CDKAL1, PLCG1) previously associated with birthweight.
Signaling dynamics distinguish high and low priority neutrophil attractant receptors
Authors: Lundgren Stefan M. , Rocha-Gregg Briana L. , Akdoǧan Emel , Mysore Maya N. , Hayes Samuel L. , Collins Sean R.
Published: May 2022

Human neutrophils respond to multiple chemical attractants to guide their migration from the vasculature to sites of infection and injury, where they clear pathogens and amplify inflammation. To properly focus their responses during this complex navigation, neutrophils distinguish between attractants to modulate their responses. They prioritize pathogen and injury derived signals over long-range inflammatory signals secreted by host cells. Different attractants can also drive qualitatively different modes of migration. As receptors recognizing both classes of attractant couple to Gαi G-proteins, it remains unclear how downstream signaling pathways distinguish and prioritize between the inputs. Here, we use live-cell imaging to demonstrate that the responses differ in their signaling dynamics: low priority attractants cause transient responses, while responses to high priority attractants are sustained. We observe this difference in both primary neutrophils and differentiated HL-60 cells, for signaling outputs of calcium, a major regulator of secretion, and Cdc42, a primary regulator of polarity and cell steering. We find that the rapid attenuation of Cdc42 activation in response to LTB4 depends on the threonine 308 and serine 310 phosphorylation sites in the C-terminal tail of its receptor LTB4R, in a manner independent of endocytosis. Mutation of these residues to alanine impairs attractant prioritization, although it does not affect attractant-dependent differences in migration persistence. Our results indicate that distinct temporal regulation of shared signaling pathways distinguishes receptors and contributes to chemoattractant prioritization.
Crystal structure of an extracellular superoxide dismutase from Onchocerca volvulus and implications for parasite-specific drug development
Authors: Moustafa Amr , Perbandt Markus , Liebau Eva , Betzel Christian , Falke Sven
Published: May 2022

Superoxide dismutases (SODs) are metalloproteins that are responsible for the dismutation of superoxide anion radicals. SODs are consequently protective against oxidative damage to cellular components. Among other protective mechanisms, the filarial parasite Onchocerca volvulus has a well developed defense system to scavenge toxic free radicals using SODs during migration and sojourning of the microfilariae and adult worms in the human body. O. volvulus is responsible for the neglected disease onchocerciasis or `river blindness'. In the present study, an extracellular Cu/Zn-SOD from O. volvulus (OvEC-SOD) was cloned, purified and crystallized to obtain structural insight into an attractive drug target with the potential to combat onchocerciasis. The recombinant OvEC-SOD forms a dimer and the protein structure was solved and refined to 1.55 Å resolution by X-ray crystallography. Interestingly, a sulfate ion supports the coordination of the conserved copper ion. The overall protein shape was verified by small-angle X-ray scattering. The enzyme shows a different surface charge distribution and different termini when compared with the homologous human SOD. A distinct hydrophobic cleft to which both protomers of the dimer contribute was utilized for a docking approach with compounds that have previously been identified as SOD inhibitors to highlight the potential for individual structure-based drug development.
How did the COVID-19 lockdown impact patients with dual diagnoses?
Authors: Ghosh Abhishek , Bn Subodh , Sharma Kshitiz , Roub Fazl e , Mahintamani Tathagata , Basu Debasish , Mattoo Surendra Kumar
Published: May 2022

Purpose

Individuals with dual diagnoses might experience significant clinical and social vulnerabilities during the pandemic and lockdown. This study aims to compare medication adherence, substance use, clinical stability and overall functioning before and during lockdown periods.

Design/methodology/approach

This was a cross-sectional survey among patients registered in dual diagnosis clinic of an addiction psychiatry center in Northern India between March 2019 and February 2020. This study approached 250 patients for telephonic interviews. This study assessed adherence to medications with the brief adherence rating scale (BARS). Global functioning was measured by global assessment of functioning. Clinical interviews assessed substance use and the clinical status of psychiatric disorders.

Findings

One hundred fifty patients were recruited. The mean age of the sample was 35.8 years. The sample had a slight preponderance of alcohol dependence. Depressive disorder was the largest category of psychiatric diagnosis. Compared to prelockdown period, during the lockdown, there were an increased number of days of nonadherence (X2 17.61, p <  0.05), proportion of patients underdosing (X2 8.96, p = 0.003) and lower BARS scores (t = 10.52, df = 144, p < 0.0001). More patients were abstinent from substances during the lockdown (X2 49.02, p < 0.0001). Clinical stability of psychiatric disorders did not differ during the two-time points, but overall functioning decreased during the lockdown (t = 2.118, p = 0.036). This study observed a small positive correlation (r = 0.2, p = 0.02) between functioning and adherence levels.

Originality/value

Lockdown was associated with poor medication adherence, change in substance use patterns and functional impairment. In the future, treatment programs and policies must take preemptive steps to minimize the effects of restrictions.
Idiosyncratic volatility, turnover and the cross-section of stock returns: evidence from the Korean stock market
Authors: Kim Jungmu , Lee Changjun , Lee Woo-Hyuk , Ok Youngkyung , Truong Thuy Thi Thu
Published: May 2022

Purpose

The authors aim to understand the driving forces behind the idiosyncratic volatility puzzle in the Korean stock market. The authors study the Korean stock market because previous works report a strong idiosyncratic volatility puzzle in Korea, and the market for the exchange-traded funds (ETFs) including low volatility ETFs has experienced drastic growth in Korea.

Design/methodology/approach

Using common stocks listed either on KOSPI or KOSDAQ over the period 1997–2016, the authors estimate idiosyncratic volatility using the Fama–French three-factor model. In addition, based on prior literature, the authors use turnover as a proxy for overvaluation. The authors then study the role of turnover in understanding the idiosyncratic volatility puzzle in Korea.

Findings

The authors find that turnover is highly associated with idiosyncratic volatility. Turnover is extremely large among firms with high idiosyncratic volatility and the puzzle disappears after we control for turnover, meaning that turnover subsumes the explanatory power of idiosyncratic volatility for equity returns. The authors also find underperformance of stocks with high turnover and high idiosyncratic volatility exclusively during earnings announcement periods. Overall, our finding implies that the puzzle arises since high idiosyncratic volatility stocks due to high turnover are overvalued and experience correction afterwards.

Originality/value

Literature has suggested explanations based on lottery preferences of investors and market frictions behind the idiosyncratic volatility puzzle. What makes our study distinct from previous work is that we find the role of turnover in understanding the idiosyncratic volatility puzzle using turnover measure as a proxy for overvaluation in the Korean stock market.
Value co-creation and performance within Brazilian innovation environments
Authors: dos Santos Gustavo Piardi Piardi , Schmidt Serje , Gonçalves Manuela Albornoz , Bohnenberger Maria Cristina
Published: May 2022

Purpose

This study aims to analyse value co-creation in innovative firms within innovation environments (IEs) in the south region of Brazil from a processual and dynamic perspective, including its antecedents, initiatives and its outcomes in the multiple facets of the firms’ performance.

Design/methodology/approach

A qualitative and quantitative multi-method study was carried out with the management and support teams of these IEs, as well as with a sample of 91 companies installed.

Findings

The results helped clarify the value co-creation process in IEs of an emerging economy, suggesting under which conditions and how value co-creation practices are performed and its significant role in specific performance dimensions of companies.

Research limitations/implications

The study contributes to companies and IEs within emerging economies to prioritize practices related to the co-creation of value to enhance their results.

Originality/value

In emerging countries, IEs struggle to apply their scarce resources to the development of hosted firms. Having value co-creation as a concept that presupposes the involvement of the beneficiary and other actors to improve the companies’ value proposition, its practice may constitute a valuable ally in this effort. However, the dynamics of value co-creation in such environments, its antecedents and specific outcomes are still unclear.
Online counselling and therapy
Authors: Prescott Julie
Published: May 2022

Purpose

In this edition of digital innovations I will briefly discuss online therapy/counselling.

Design/methodology/approach

The online environment can offer a safe space for many individuals to seek support. The virtual world affords many features the offline world does not.

Findings

In this and the next digital innovations feature I want to look at this online support and how people provide, as well as, seek support virtually.

Originality/value

In this edition I will briefly look at online counselling with a focus on young people, who are a client group, research has found, often prefer to access mental health services online.
Biocrusts increase the resistance to warming‐induced increases in topsoil P pools
Authors: García‐Velázquez Laura , Gallardo Antonio , Ochoa Victoria , Gozalo Beatriz , Lázaro Roberto , Maestre Fernando T.
Published: May 2022

Ongoing global warming and alterations in rainfall patterns driven by climate change are known to have large impacts on biogeochemical cycles, particularly on drylands. In addition, the global increase in atmospheric nitrogen (N) deposition can destabilize primary productivity in terrestrial ecosystems, and phosphorus (P) may become the most limiting nutrient in many terrestrial ecosystems. However, the impacts of climate change on soil P pools in drylands remain poorly understood. Furthermore, it is unknown whether biocrusts, a major biotic component of drylands worldwide, modulate such impacts.

Here we used two long‐term (8–10 years) experiments conducted in Central (Aranjuez) and SE (Sorbas) Spain to test how a ~2.5°C warming, a ~30% rainfall reduction and biocrust cover affected topsoil (0–1 cm) P pools (non‐occluded P, organic P, calcium bound P, occluded P and total P).

Warming significantly increased most P pools—except occluded P—in Aranjuez, whereas only augmented non‐occluded P in Sorbas. The rainfall reduction treatment had no effect on the soil P pools at any experimental site. Biocrusts increased most soil P pools and conferred resistance to simulated warming for major P pools at both sites, and to rainfall reduction for non‐occluded and occluded P in Aranjuez.

Synthesis. Our findings provide novel insights on the responses of soil P pools to warming and rainfall reduction, and highlight the importance of biocrusts as modulators of these responses in dryland ecosystems. Our results suggest that the observed negative impacts of warming on dryland biocrust communities will decrease their capacity to buffer changes in topsoil P driven by climate change.