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Cryptosporidiosis is a leading cause of life-threatening diarrhea in young children in resource-poor settings. Susceptibility rapidly declines with age, associated with changes in the microbiota. To explore microbial influences on susceptibility, we screened 85 microbiota-associated metabolites enriched in the adult gut for their effects on C. parvum growth in vitro. We identified eight inhibitory metabolites in three main classes: secondary bile salts/acids, a vitamin B6 precursor, and indoles. Growth restriction of C. parvum by indoles did not depend on the host aryl hydrocarbon receptor (AhR) pathway. Instead, treatment impaired host mitochondrial function and reduced total cellular ATP, as well as directly reduced the membrane potential in the parasite mitosome, a degenerate mitochondria. Oral administration of indoles, or reconstitution of the gut microbiota with indole producing bacteria, delayed life cycle progression of the parasite in vitro and reduced severity of C. parvum infection in mice. Collectively, these findings indicate that microbiota metabolites contribute to colonization resistance to Cryptosporidium infection.

INTRODUCTION: Restrained, emotional and intuitive eating were examined in relation to each other and as correlates of participants' weight status, body image and self-esteem. In some past research, restrained and emotional eating have been associated with higher weight status and poorer mental health, while intuitive eating is more frequently linked to lower weight status and more positive well-being. However, these eating styles have rarely been examined together and never in a large cross-country sample. METHOD: Six-thousand two-hundred and seventy-two (6272) emerging adults (M age = 21.54 years, SD = 3.13) completed scales from the Three-Factor Eating Questionnaire, the Eating Disorders Examination Questionnaire, the Intuitive Eating Scale-2, the Multidimensional Body Self Relations Questionnaire, the Rosenberg Self-Esteem Scale, and provided weight and height information that was used to calculate body mass index (BMI). Participants resided in Australia, Belgium, Canada, China, Italy, Japan, Spain and the United States and provided information using an online survey. RESULTS: Path analyses for the entire sample revealed significant pathways between higher intuitive eating and higher body satisfaction and self-esteem, and lower BMIs among participants. Higher levels of restrained and emotional eating were associated with lower body satisfaction and self-esteem, and higher BMIs among participants. Minor cross-country differences were evident in these patterns of relations, but intuitive eating emerged as a consistent predictor across countries. CONCLUSION: Overall, findings suggest that efforts should be made to increase intuitive eating among emerging adults and to support individual and macrolevel interventions to decrease restrained and emotional eating behaviours. ispartof: BRITISH JOURNAL OF HEALTH PSYCHOLOGY vol:28 issue:1 pages:136-155 ispartof: location:England status: published

Background App-based interventions designed to prevent and treat eating disorders have considerable potential to overcome known barriers to treatment seeking. Existing apps have shown efficacy in terms of symptom reduction; however, uptake and retention issues are common. To ensure that apps meet the needs and preferences of those for whom they were designed, it is critical to understand the lived experience of potential users and involve them in the process of design, development, and delivery. However, few app-based interventions are pretested on and co-designed with end users before randomized controlled trials. Objective To address the issue, this study used a highly novel design thinking approach to provide the context and a lived experience perspective of the end user, thus allowing for a deeper level of understanding. Methods In total, 7 young women (mean age 25.83, SD 5.34, range 21-33 years) who self-identified as having a history of body image issues or eating disorders were recruited. Participants were interviewed about their lived experience of body image and eating disorders and reported their needs and preferences for app-based eating disorder interventions. Traditional (thematic analysis) and novel (empathy mapping; visually depicting and empathizing with the user’s personal experience) analyses were performed, providing a lived experience perspective of eating disorders and identifying the needs and preferences of this population in relation to app-based interventions for eating disorders. Key challenges and opportunities for app-based eating disorder interventions were also identified. Results Findings highlighted the importance of understanding and identifying problematic eating disorder symptoms for the user, helpful practices for recovery that identify personal values and goals, the role of social support in facilitating hope, and aspects of usability to promote continued engagement and recovery. Conclusions Practical guidance and recommendations are described for those developing app-based eating disorder interventions. These findings have the potential to inform practices to enhance participant uptake and retention in the context of app-based interventions for this population.

Traumatic brain injury (TBI) patients are at high risk for disruption of the gut microbiome. Previously, we have demonstrated that broad-spectrum antibiotic exposure after TBI drastically alters the gut microbiota and modulates neuroinflammation, neurogenesis, and long-term fear memory. However, these data did not determine if the impact of antibiotic exposure on the brain's response to injury was mediated directly by antibiotics or indirectly via modulation of the gut microbiota. We designed two different approaches to address this knowledge gap utilizing fecal microbiota transplantation (FMT) from control and antibiotic-treated mice (VNAM: vancomycin, neomycin, ampicillin and metronidazole) into germ free (GF) mice prior to injury and exposing single pathogen free (SPF) mice to a 2-week period of antibiotics prior to injury but discontinuing antibiotics 72 hours prior to injury. GF mice receiving FMT from VNAM exposed mice (GF-VNAM) demonstrated reduced gut bacterial alpha diversity and richness compared with GF mice receiving FMT from control. At 7 days post injury, GF-VNAM had increased microglial activation, reduced infiltration of T cells, and decreased neurogenesis 7 days after injury. Similarly, SPF mice exposed to antibiotics prior to but not after injury demonstrated similar alterations in neuroinflammation and neurogenesis compared to control mice. These data support our hypothesis implicating the gut microbiota as an important modulator of the neuroinflammatory process and neurogenesis after TBI and provide an exciting new approach for neuroprotective therapeutics for TBI.

Noroviruses are a leading cause of gastroenteritis worldwide, yet the molecular mechanisms of how host antiviral factors restrict norovirus infection are poorly understood. Here, we present a CRISPR activation screen that identifies mouse genes which inhibit murine norovirus (MNV) replication. Detailed analysis of the major hit Trim7 demonstrates a potent inhibition of the early stages of MNV replication. Leveraging in vitro evolution, we identified MNV mutants that escape Trim7 restriction by altering the cleavage of the viral NS6-7 polyprotein precursor. NS6, but not the NS6-7 precursor, directly binds the substrate-binding domain of Trim7. Surprisingly, the selective polyprotein processing that enables Trim7 evasion inflicts a significant evolutionary burden, as viruses with decreased NS6-7 cleavage are strongly attenuated in viral replication and pathogenesis. Our data provide an unappreciated mechanism of viral evasion of cellular antiviral factors through selective polyprotein processing and highlight the evolutionary tradeoffs in acquiring resistance to host restriction factors. IMPORTANCE To maximize a limited genetic capacity, viruses encode polyproteins that can be subsequently separated into individual components by viral proteases. While classically viewed as a means of economy, recent findings have indicated that polyprotein processing can spatially and temporally coordinate the distinct phases of the viral life cycle. Here, we present a function for alternative polyprotein processing centered on immune defense. We discovered that selective polyprotein processing of the murine norovirus polyprotein shields MNV from restriction by the host antiviral protein Trim7. Trim7 can bind the viral protein NS6 but not the viral precursor protein NS6-7. Our findings provide insight into the evolutionary pressures that define patterns of viral polyprotein processing and uncover a trade-off between viral replication and immune evasion.

Mutations in the macroautophagy/autophagy gene

Interferon-lambda (IFN-λ) protects intestinal epithelial cells (IECs) from enteric viruses by inducing expression of antiviral IFN-stimulated genes (ISGs). Here, we find that bacterial microbiota stimulate a homeostatic ISG signature in the intestine of specific pathogen-free mice. This homeostatic ISG expression is restricted to IECs, depends on IEC-intrinsic expression of IFN-λ receptor (Ifnlr1), and is associated with IFN-λ production by leukocytes. Strikingly, imaging of these homeostatic ISGs reveals localization to pockets of the epithelium and concentration in mature IECs. Correspondingly, a minority of mature IECs express these ISGs in public single-cell RNA sequencing datasets from mice and humans. Furthermore, we assessed the ability of orally-administered bacterial components to restore localized ISGs in mice lacking bacterial microbiota. Lastly, we find that IECs lacking Ifnlr1 are hyper-susceptible to initiation of murine rotavirus infection. These observations indicate that bacterial microbiota stimulate ISGs in localized regions of the intestinal epithelium at homeostasis, thereby preemptively activating antiviral defenses in vulnerable IECs to improve host defense against enteric viruses.

The influence of the gut microbiota on traumatic brain injury (TBI) is presently unknown. This knowledge gap is of paramount clinical significance as TBI patients are highly susceptible to alterations in the gut microbiota by antibiotic exposure. Antibiotic-induced gut microbial dysbiosis established prior to TBI significantly worsened neuronal loss and reduced microglia activation in the injured hippocampus with concomitant changes in fear memory response. Importantly, antibiotic exposure for 1 week after TBI reduced cortical infiltration of Ly6Chigh monocytes, increased microglial pro-inflammatory markers, and decreased T lymphocyte infiltration, which persisted through 1 month post-injury. Moreover, microbial dysbiosis was associated with reduced neurogenesis in the dentate gyrus 1 week after TBI. By 3 months after injury (11 weeks after discontinuation of the antibiotics), we observed increased microglial proliferation, increased hippocampal neuronal loss, and modulation of fear memory response. These data demonstrate that antibiotic-induced gut microbial dysbiosis after TBI impacts neuroinflammation, neurogenesis, and fear memory and implicate gut microbial modulation as a potential therapeutic intervention for TBI. Supplementary Information The online version contains supplementary material available at 10.1186/s40478-021-01137-2.

Mutations in the macroautophagy/autophagy gene EPG5 are responsible for Vici syndrome, a human genetic disease characterized by combined immunodeficiency. Previously, we found that epg5−/- mice exhibit hyperinflammation in the lungs mediated by IL1B/IL-1β and TNF/TNFα, resulting in resistance to influenza. Here, we find that disruption of Epg5 results in protection against multiple enteric viruses including norovirus and rotavirus. Gene expression analysis reveals IFNL/IFN-λ responsive genes as a key alteration. Further, mice lacking Epg5 exhibit substantial alterations of the intestinal microbiota. Surprisingly, germ-free mouse studies indicate Epg5-associated inflammation of both the intestine and lung is microbiota-independent. Genetic studies support IFNL signaling as the primary mediator of resistance to enteric viruses, but not of microbial dysbiosis, in epg5−/- mice. This study unveils an important role, unexpectedly independent of the microbiota, for autophagy gene Epg5 in host organism protection by modulating intestinal IFNL responses. Abbreviations: CTNNB1: catenin (cadherin associated protein), beta 1; DAPI: 4′,6-diamidino-2-phenylindole; EPG5: ectopic P-granules autophagy protein 5 homolog (C. elegans); FT: fecal transplant; IFI44: interferon-induced protein 44; IFIT1: interferon-induced protein with tetratricopeptide repeats 1; IFNG/IFN-γ: interferon gamma; IFNL/IFN-λ: interferon lambda; IFNLR1: interferon lambda receptor 1; IL1B/IL-1β: interleukin 1 beta; ISG: interferon stimulated gene; GF: germ-free; LEfSe: linear discriminant analysis effect size; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MNoV: murine norovirus; MX2: MX dynamin-like GTPase 2; OAS1A: 2’-5’ oligoadenylate synthetase 1A; RV: rotavirus; SPF: specific-pathogen free; SQSTM1/p62: sequestosome 1; STAT1: signal transducer and activator of transcription 1; STING1: stimulator of interferon response cGAMP interactor 1; TBK1: TANK-binding kinase 1; TNF/TNFα: tumor necrosis factor

SUMMARY STING modulates immunity by responding to bacterial and endogenous cyclic dinucleotides (CDNs). Humans and mice with STING gain-of-function mutations develop a syndrome known as STING-associated vasculopathy with onset in infancy (SAVI), which is characterized by inflammatory or fibrosing lung disease. We hypothesized that hyperresponsiveness of gain-of-function STING to bacterial CDNs might explain autoinflammatory lung disease in SAVI mice. We report that depletion of gut microbes with oral antibiotics (vancomycin, neomycin, and ampicillin [VNA]) nearly eliminates lung disease in SAVI mice, implying that gut microbes might promote STING-associated autoinflammation. However, we show that germ-free SAVI mice still develop severe autoinflammatory disease and that transferring gut microbiota from antibiotics-treated mice to germ-free animals eliminates lung inflammation. Depletion of anaerobes with metronidazole abolishes the protective effect of the VNA antibiotics cocktail, and recolonization with the metronidazole-sensitive anaerobe Bacteroides thetaiotaomicron prevents disease, confirming a protective role of a metronidazole-sensitive microbe in a model of SAVI., Graphical abstract, In brief Platt et al. report that oral antibiotics but not germ-free conditions prevent autoinflammatory lung disease in a mouse model of STING-associated vasculopathy with onset in infancy (SAVI). Recolonization of SAVI mice with either Bacteroidales-enriched stool or Bacteroides thetaiotaomicron is protective in this model of STING-associated autoinflammatory lung disease.

Interferons (IFNs) are key controllers of viral replication, with intact IFN responses suppressing virus growth and spread. Using the murine norovirus (MNoV) system, we show that IFNs exert selective pressure to limit the pathogenic evolutionary potential of this enteric virus. In animals lacking type I IFN signaling, the nonlethal MNoV strain CR6 rapidly acquired enhanced virulence via conversion of a single nucleotide. This nucleotide change resulted in amino acid substitution F514I in the viral capsid, which led to >10,000-fold higher replication in systemic organs including the brain. Pathogenicity was mediated by enhanced recruitment and infection of intestinal myeloid cells and increased extraintestinal dissemination of virus. Interestingly, the trade-off for this mutation was reduced fitness in an IFN-competent host, in which CR6 bearing F514I exhibited decreased intestinal replication and shedding. In an immunodeficient context, a spontaneous amino acid change can thus convert a relatively avirulent viral strain into a lethal pathogen., Author summary The evolution of viruses both within a single host and during transmission between hosts often leads to novel characteristics as mutations develop, with increased lethality or transmissibility being particularly concerning potential outcomes. Here, using a novel in vivo experimental evolution strategy with intestinal pathogen murine norovirus (MNoV), we identified a single nucleotide mutation that consistently and exclusively arose when mice lacking interferon signaling, a key aspect of the early innate immune response, were infected intracranially with a nonlethal strain of MNoV. This mutation was both sufficient and necessary for viral virulence, conferring virulence by enhanced infection of immune cells to facilitate systemic spread, representing a shift in the cell types infected by the virus. Conversely, this mutation was also associated with more limited infection in the intestine, suggesting a fitness cost. Our work identifies key immunological constraints on the evolution of virulence and provides specific mechanistic insights into viral pathogenesis.

Summary Rotavirus vaccines (RVVs) have substantially diminished mortality from severe rotavirus (RV) gastroenteritis but are significantly less effective in low- and middle-income countries (LMICs), limiting their life-saving potential. The etiology of RVV’s diminished effectiveness remains incompletely understood, but the enteric microbiota has been implicated in modulating immunity to RVVs. Here, we analyze the enteric microbiota in a longitudinal cohort of 122 Ghanaian infants, evaluated over the course of 3 Rotarix vaccinations between 6 and 15 weeks of age, to assess whether bacterial and viral populations are distinct between non-seroconverted and seroconverted infants. We identify bacterial taxa including Streptococcus and a poorly classified taxon in Enterobacteriaceae as positively correlating with seroconversion. In contrast, both bacteriophage diversity and detection of Enterovirus B and multiple novel cosaviruses are negatively associated with RVV seroconversion. These findings suggest that virome-RVV interference is an underappreciated cause of poor vaccine performance in LMICs., Graphical abstract, Highlights • Longitudinal analysis of microbiota of Ghanaian infants receiving rotavirus vaccine • Streptococcus and Enterobacteriaceae taxa positively associate with RVV seroconversion • Enterovirus B, Cosavirus A, and phage richness negatively associate with RVV serostatus, Rotavirus vaccines have diminished performance in low- and middle-income countries, leaving children vulnerable to life-threatening gastroenteritis. Kim et al. employed unbiased metagenomic sequencing of longitudinally collected fecal samples from 122 Ghanaian infants and found that members of the virome were significantly associated with constrained rotavirus vaccine immunogenicity, potentially explaining this diminished performance.

This study explores the development of self and gender identity within the lived experience of transgender individuals who were assigned female at birth and now identify as male or male spectrum. A psychoanalytically informed interview technique was employed here, involving six participants, aged 20–37 for 3–4 one-hour interviews. Alongside close attention to the content and the manner of representation of self and other across interviews, the analysis was also informed by counter-transference processes. Three core themes emerged from the data: ‘What’s in a Name?’; ‘Rejected, Bullied, Ignored and Forgotten’; and ‘I’m a Boy (not a Girl)’. Recollections of traumatic experiences and the use of laughter were other notable details that appeared across participants. Links are made between the emerging themes and concepts of incongruent mirroring and the development of a false self. Directions for further research and clinical implications for working with transgender clients in a psychotherapeutic context are a...

The influence of the gut microbiota on traumatic brain injury (TBI) is presently unknown. This knowledge gap is of paramount clinical significance as TBI patients are highly susceptible to alterations in the gut microbiota by antibiotic exposure. Antibiotic-induced gut microbial dysbiosis established prior to TBI significantly worsened neuronal loss and reduced microglia activation in the injured hippocampus with concomitant changes in fear memory response. Importantly, microbial dysbiosis after TBI reduced hippocampal infiltration of Ly6Chigh monocytes followed by a decreased presence of CD4+ and CD8+ T cells that persisted through 1 month post-injury, and increase of microglial pro-inflammatory markers. By 3 months, these mice had a larger percentage of microglia with a persistent amoeboid morphology, increased neuronal loss, and a maladaptive fear memory response. These data demonstrate the important role the gut microbiota plays in neuroinflammation and recovery after TBI and implicate gut microbial modulation as a potential therapeutic intervention.

Noroviruses (NoVs) are the leading cause of acute viral gastroenteritis worldwide, causing up to 700 million infections and 200,000 deaths annually, and treatment is limited to supportive care as there are currently no targeted antivirals nor vaccines against NoVs. Therefore, it is critical to discover novel antivirals and develop targeted interventions in order to improve outcomes. Here we have used a novel genome-wide CRISPR activation screening approach to identify host genes that can inhibit murine norovirus (MNoV) infection or replication. A substantial number of high scoring gene candidates acted in interferon and immune regulation signaling networks, but several were not previously associated with antiviral activity or immunity. TRIM7, the strongest screen hit, was a little studied E3 ubiquitin ligase associated with metabolism and some cancers, yet its expression served as a powerful antiviral in an MNoV-infected cell. Since our initial screen, TRIM7 has begun to emerge as a strategic player in both positive and negative regulation of the innate immune response during infection. We have since characterized the antiviral mechanism of action of TRIM7 against MNoV in vitro, and have found TRIM7 to be acting early in the viral life cycle to limit viral protein production. Co-immunoprecipitation and in vitro viral evolution experiments have identified MNoV NS6 (viral protease) and NS7 (RNA-dependent RNA polymerase) as important targets of the antiviral activity of TRIM7, and also point to key residues of interest associated with MNoV resistance to TRIM7. Finally, we have investigated the relevance of TRIM7 during in vivo infection using knock-in mouse lines to determine tissue specificity and potency of the antiviral effect.

Fishes of the New World cyprinodontiform family Fundulidae display a wide variety of tolerance to environmental conditions, making them a valuable model system for comparative, evolutionary, and environmental studies. Despite numerous attempts to resolve the phylogenetic relationships of family Fundulidae, the basal structure of the phylogeny remains unresolved. The lack of a robust and fully resolved phylogeny for family Fundulidae and its most speciose genus Fundulus is an impediment to future research. This study utilized novel RNA-sequencing data for phylogenetic inference among16 members of Fundulidae to better refine the basal nodes of the family and confront long-standing questions regarding (1) the monophyletic status of genus Fundulus, and validity of the Lucania and recently synonymized Adinia genera; (2) the relationship of the west coast endemic Fundulus parvipinnis and F. lima to other Fundulus species; and (3) the validity of subgeneric classifications. In addition, previously published nuclear gene sequences for 32 Fundulidae species were re-analyzed in combination with novel RNA-sequencing data. Maximum likelihood and Bayesian analyses generated identical phylogenies with strong statistical support at nearly all nodes, demonstrating the utility of RNA-sequencing data in constructing robust phylogenies not achievable by previous methods. While many past hypothesized evolutionary relationships for Fundulidae were reinforced, several alternative relationships are hypothesized at basal nodes resulting in a re-analysis of the deeper structure of family Fundulidae. These results reveal family Fundulidae as a paraphyletic grouping of members of genus Fundulus and Lucania and supports the previous synonymy of genus Adinia with genus Fundulus.

The present study examined individual latent changes in posttraumatic stress disorder (PTSD) symptoms over a 60-month period after an industrial disaster. Participants were recruited from survivors of a factory explosion. Participants were assessed retrospectively for peritraumatic reactions and acute stress symptoms. Posttraumatic stress disorder symptoms were then assessed at 6, 15, and 60 months. Using structural equation modeling, the authors tested 3 hypotheses of individual latent change: stability of PTSD symptoms between 6, 15, and 60 months; change between 6 and 15 months; and change between 15 and 60 months. Only one model provided a good fit suggesting that PTSD symptoms evolved between 6 and 15 months after trauma exposure and remained stable at the individual level thereafter.