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We study the noncommutativity of different orders of zero energy-momentum limit pertaining to the axial chemical potential in the chiral magnetic effect. While this noncommutativity issue originates from the pinching singularity at one-loop order, it cannot be removed by introducing a damping term to the fermion propagators. The physical reason is that modifying the propagator alone would violate the axial-vector Ward identity and as a result a modification of the longitudinal component of the axial-vector vertex is required, which contributes to chiral magnetic effect (CME). The pinching singularity with free fermion propagators was then taken over by the singularity stemming from the dressed axial-vector vertex. We show this mechanism by a concrete example. Moreover, we proved, in general, the vanishing CME in the limit order that the static limit was taken prior to the homogeneous limit in the light of Coleman-Hill theorem for a static external magnetic field. For the opposite limit that the homogeneous limit is taken first, we show that the nonvanishing CME was a consequence of the nonrenormalization of chiral anomaly for an arbitrary external magnetic field.

Background: A research priority in finding a cure for HIV is to establish methods to accurately locate and quantify where and how HIV persists in people living with HIV (PLWH) receiving suppressive antiretroviral therapy (ART). Infusing copper-64 (Cu-64) radiolabelled broadly neutralising antibodies targeting HIV envelope (Env) with CT scan and positron emission tomography (PET) identified HIV Env in tissues in SIV infected non-human primates . We aimed to determine if a similar approach was effective in people living with HIV (PLWH). Methods: Unmodified 3BNC117 was compared with 3BNC117 bound to the chelator MeCOSar and Cu-64 (Cu-64-3BNC117) in vitro to assess binding and neutralization. In a clinical trial Cu-64-3BNC117 was infused into HIV uninfected (Group 1), HIV infected and viremic (viral load, VL >1000 c/mL; Group 2) and HIV infected aviremic (VL <20 c/mL; Group 3) participants using two dosing strategies: high protein (3mg/kg unlabeled 3BNC117 combined with <5mg Cu-64-3BNC117) and trace (<5mg Cu-64-3BNC117 only). All participants were screened for 3BNC117 sensitivity from virus obtained from viral outgrowth. Magnetic resonance imaging (MRI)/PET and pharmacokinetic assessments (ELISA for serum 3BNC117 concentrations and gamma counting for Cu-64) were performed 1, 24-and 48-hours post dosing. The trial (clincialtrials.gov NCT03063788) primary endpoint was comparison of PET standard uptake values (SUVs) in regions of interest (e.g lymph node groups and gastrointestinal tract). Findings: Comparison of unmodified and modified 3BNC117 in vitro demonstrated no difference in HIV binding or neutralisation. 17 individuals were enrolled of which 12 were dosed including Group 1 (n=4, 2 high protein, 2 trace dose), Group 2 (n=6, 2 high protein, 4 trace) and Group 3 (n=2, trace only). HIV+ participants had a mean CD4 of 574 cells/microL and mean age 43 years. There were no drug related adverse effects and no differences in tissue uptake in regions of interest (e.g lymph node gut, pharynx) between the 3 groups. In the high protein dosing group, serum concentrations of 3BNC117 and gamma counts were highly correlated demonstrating that Cu-64-3BNC117 remained intact in vivo. Interpretation: In PLWH on or off ART, the intervention of infusing Cu-64-3BNC117 and MRI/PET imaging over 48 hours, was unable to detect HIV-1 env expression in vivo. Future studies should investigate alternative radiolabels such as zirconium which have a longer half-life in vivo. Funding: Funded by the Alfred Foundation, The Australian Centre for HIV and Hepatitis Virology Research with additional support from the Division of AIDS, National Institute of Allergy and Infectious Disease, US National Institutes of Health (USAI126611). JHM and SRL are supported by the Australian National Health and Medical Research Council. (C) The Author(s). Published by Elsevier B.V.

Raw vegetables are a key food for a healthy diet, but their increased consumption brings a higher risk for foodborne disease. Contamination of salad greens with Shiga toxin-producing Escherichia coli (STEC) O157:H7 has caused severe disease and important economic losses almost yearly in the United States over the last 10 years. To curb the risk of infections from contaminated produce, approaches based on bacterial virus - commonly known as bacteriophage or phage - have recently started to draw interest among other antimicrobial strategies. Phages enter bacterial cells to reproduce and cause cellular lysis to release their phage progeny at the end of their infection cycle. This lytic effect is caused by lysins, phage-encoded enzymes that have evolved to degrade the bacterial cell wall resulting in hypotonic lysis. When applied externally in their purified form, such enzymes are able to kill sensitive bacteria on contact in a similar way. Their unique bactericidal properties have made lysins effective antimicrobial agents in a variety of applications, from treating multidrug-resistant infections in humans to controlling bacterial contamination in several areas, including microbiological food safety. Here we describe a novel lysin, namely PlyEc2, with potent bactericidal activity against key gram-negative pathogens including E. coli, Salmonella, Shigella, Acinetobacter and Pseudomonas. PlyEc2 displayed high bactericidal activity against STEC to a concentration of 12.5 mu g/ml under different pH conditions. This lysin was also able to reduce the bacterial titer of several pathogenic strains in vitro by more than 5 logarithmic units, resulting in complete sterilization. Importantly, PlyEc2 proved to be a powerful produce decontamination agent in its ability to clear 99.7% of contaminating STEC O157:H7 in our Romaine lettuce leaf model. PlyEc2 was also able to eradicate 99.8% of the bacteria contaminating the washing solution, drastically reducing the risk of cross-contamination during the washing process. A sensory evaluation panel found that treatment with PlyEc2 did not alter the visual and tactile quality of lettuce leaves compared to the untreated leaves. Our study is the first to describe a highly effective lysin treatment to control gram-negative pathogenic contamination on fresh lettuce without the addition of membrane destabilizing agents.

The formation of cellular microtubule networks is regulated by the gamma-tubuhn ring complex (gamma-TuRC). This similar to 2.3 MD assembly of >31 proteins includes y-tubuhn and GCP2-6, as well as MZT1 and an actin-like protein in a "lumenal bridge" (LB). The challenge of reconstituting the gamma-TuRC has limited dissections of its assembly and function. Here, we report a biochemical reconstitution of the human gamma-TuRC (gamma-TuRC-GFP) as a similar to 35 S complex that nucleates microtubules in vitro. In addition, we generate a subcomplex, gamma-TuRC(Delta LB)-GFP, which lacks MZT1 and actin. We show that gamma-TuRC(Delta LB)-GFP nucleates microtubules in a guanine nucleotide-dependent manner and with similar efficiency as the holocomplex. Electron microscopy reveals that gamma-TuRC-GFP resembles the native gamma-TuRC architecture, while gamma-TuRC(Delta LB)-GFP adopts a partial cone shape presenting only 8-10 gamma-tubulin subunits and lacks a well-ordered lumenal bridge. Our results show that the gamma-TuRC can be reconstituted using a limited set of proteins and suggest that the LB facilitates the self-assembly of regulatory interfaces around a microtubule-nucleating "core" in the holocomplex.

The high-throughput phenotypic screen (HTPS) has become an emerging technology to discover synthetic small molecules that regulate stem cell fates. Here, we review the application of HTPS to identify small molecules controlling stem cell renewal, reprogramming, differentiation, and lineage conversion. Moreover, we discuss the use of HTPS to discover small molecules/polymers mimicking the stem cell extracellular niche. Furthermore, HTPSs have been applied on whole-animal models to identify small molecules regulating stem cell renewal or differentiation in vivo. Finally, we discuss the examples of the utilization of HTPS in stem cellbased disease modeling, as well as in the discovery of novel drug candidates for cancer, diabetes, and infectious diseases. Overall, HTPSs have provided many powerful tools for the stem cell field, which not only facilitate the generation of functional cells/tissues for replacement therapy, disease modeling, and drug screening, but also help dissect molecular mechanisms regulating physiological and pathological processes.

SARS-CoV-2 is responsible for the ongoing world-wide pandemic which has already taken more than two million lives. Effective treatments are urgently needed. The enzymatic activity of the HECT-E3 ligase family members has been implicated in the cell egression phase of deadly RNA viruses such as Ebola through direct interaction of its VP40 Protein. Here we report that HECT-E3 ligase family members such as NEDD4 and WWP1 interact with and ubiquitylate the SARS-CoV-2 Spike protein. Furthermore, we find that HECT family members are overexpressed in primary samples derived from COVID-19 infected patients and COVID-19 mouse models. Importantly, rare germline activating variants in the NEDD4 and WWP1 genes are associated with severe COVID-19 cases. Critically, I3C, a natural NEDD4 and WWP1 inhibitor from Brassicaceae, displays potent antiviral effects and inhibits viral egression. In conclusion, we identify the HECT family members of E3 ligases as likely novel biomarkers for COVID-19, as well as new potential targets of therapeutic strategy easily testable in clinical trials in view of the established well-tolerated nature of the Brassicaceae natural compounds.

Ichneumonoidea is one of the most diverse lineages of animals on the planet with >48,000 described species and many more undescribed. Parasitoid wasps of this superfamily are mostly beneficial insects that attack and kill other arthropods and are important for understanding diversification and the evolution of life history strategies related to parasitoidism. Further, some lineages of parasitoids within Ichneumonoidea have acquired endogenous virus elements (EVEs) that are permanently a part of the wasp's genome and benefit the wasp through host immune disruption and behavioral control. Unfortunately, understanding the evolution of viral acquisition, parasitism strategies, diversification, and host immune disruption mechanisms, is deeply limited by the lack of a robust phylogenetic framework for Ichneumonoidea. Here we design probes targeting 541 genes across 91 taxa to test phylogenetic relationships, the evolution of parasitoid strategies, and the utility of probes to capture polydnavirus genes across a diverse array of taxa. Phylogenetic relationships among Ichneumonoidea were largely well resolved with most higher-level relationships maximally supported. We noted codon use biases between the outgroups, Braconidae, and Ichneumonidae and within Pimplinae, which were largely solved through analyses of amino acids rather than nucleotide data. These biases may impact phylogenetic reconstruction and caution for outgroup selection is recommended. Ancestral state reconstructions were variable for Braconidae across analyses, but consistent for reconstruction of idiobiosis/koinobiosis in Ichneumonidae. The data suggest many transitions between parasitoid life history traits across the whole superfamily. The two subfamilies within Ichneumonidae that have polydnaviruses are supported as distantly related, providing strong evidence for two independent acquisitions of ichnoviruses. Polydnavirus capture using our designed probes was only partially successful and suggests that more targeted approaches would be needed for this strategy to be effective for surveying taxa for these viral genes. In total, these data provide a robust framework for the evolution of Ichneumonoidea.

Previously, we proposed the hypothesis that similarities in the inflammatory response observed in acne vulgaris and degenerative disc disease (DDD), especially the central role of interleukin (IL)-1 beta, may be further evidence of the role of the anaerobic bacterium Cutibacterium (previously Propionibacterium) acnes in the underlying aetiology of disc degeneration. To investigate this, we examined the upregulation of IL-1 beta, and other known IL-1 beta-induced inflammatory markers and neurotrophic factors, from nucleus-pulposus-derived disc cells infected in vitro with C. acnes for up to 48 h. Upon infection, significant upregulation of IL-1 beta, alongside IL-6, IL-8, chemokine (C-C motif) ligand 3 (CCL3), chemokine (C-C motif) ligand 4 (CCL4), nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), was observed with cells isolated from the degenerative discs of eight patients versus non-infected controls. Expression levels did, however, depend on gene target, multiplicity and period of infection and, notably, donor response. Pre-treatment of cells with clindamycin prior to infection significantly reduced the production of pro-inflammatory mediators. This study confirms that C. acnes can stimulate the expression of IL-1 beta and other host molecules previously associated with pathological changes in disc tissue, including neo-innervation. While still controversial, the role of C. acnes in DDD remains biologically credible, and its ability to cause disease likely reflects a combination of factors, particularly individualised response to infection.

During the COVID-19 pandemic, the scientific community developed predictive models to evaluate potential governmental interventions. However, the analysis of the effects these interventions had is less advanced. Here, we propose a data-driven framework to assess these effects retrospectively. We use a regularized regression to find a parsimonious model that fits the data with the least changes in the Rt parameter. Then, we postulate each jump in Rt as the effect of an intervention. Following the do-operator prescriptions, we simulate the counterfactual case by forcing Rt to stay at the pre-jump value. We then attribute a value to the intervention from the difference between true evolution and simulated counterfactual. We show that the recommendation to use facemasks for all activities would reduce the number of cases by 200,000 (95% CI 190,000-210,000) in Connecticut, Massachusetts, and New York State. The framework presented here might be used in any case where cause and effects are sparse in time.

Staphylococcus saprophyticus is a primary cause of community-acquired urinary tract infections (UTIs) in young women. S. saprophyticus colonizes humans and animals but basic features of its molecular epidemiology are undetermined. We conducted a phylogenomic analysis of 321 S. saprophyticus isolates collected from human UTIs worldwide during 1997-2017 and 232 isolates from human UTIs and the pig-processing chain in a confined region during 2016-2017. We found epidemiologic and genomic evidence that the meat-production chain is a major source of S. saprophyticus causing human UTIs; human microbiota is another possible origin. Pathogenic S. saprophyticus belonged to 2 lineages with distinctive generic features that are globally and locally disseminated. Pangenome-wide approaches identified a strong association between pathogenicity and antimicrobial resistance, phages, platelet binding proteins, and an increased recombination rate. Our study provides insight into the origin, transmission, and population structure of pathogenic S. saprophyticus and identifies putative new virulence factors.