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Probiotic bacteria have been proposed as an alternative to antibiotics for the control of antimicrobial resistant enteric pathogens. The mechanistic details of this approach remain unclear, in part because pathogen reduction appears to be both strain and ecology dependent. Here we tested the ability of five probiotic strains, including some from common probiotic genera Lactobacillus and Bifidobacterium, to reduce binding of Salmonella enterica sv. Typhimurium to epithelial cells in vitro. Bifidobacterium longum subsp. infantis emerged as a promising strain; however, S. Typhimurium infection outcome in epithelial cells was dependent on inoculation order, with B. infantis unable to rescue host cells from preceding or concurrent infection. We further investigated the complex mechanisms underlying this interaction between B. infantis, S. Typhimurium, and epithelial cells using a multi-omics approach that included gene expression and altered metabolism via metabolomics. Incubation with B. infantis repressed apoptotic pathways and induced anti-inflammatory cascades in epithelial cells. In contrast, co-incubation with B. infantis increased in S. Typhimurium the expression of virulence factors, induced anaerobic metabolism, and repressed components of arginine metabolism as well as altering the metabolic profile. Concurrent application of the probiotic and pathogen notably generated metabolic profiles more similar to that of the probiotic alone than to the pathogen, indicating a central role for metabolism in modulating probiotic-pathogen-host interactions. Together these data imply crosstalk via small molecules between the epithelial cells, pathogen and probiotic that consistently demonstrated unique molecular mechanisms specific probiotic/pathogen the individual associations.
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Feline chronic gingivostomatitis (FCGS) is a debilitating inflammatory oral mucosal disease with a multifactorial etiology. The clinical diagnosis of FCGS is made based on inspection of severe inflammatory lesions and histological confirmation rather than a molecular diagnostic outcome. This gap limits the ability to provide an early diagnosis. In this report, we seek to provide additional diagnostic tools using genomics to aid in providing clinically relevant information. The use of in-depth diagnostic tools, like transcriptomics of diseased tissues, to diagnose FCGS and stratify patients into predictive treatment response groups would dramatically improve both clinical decisions and patient outcomes. In this study, we addressed the gap in diagnostic options using transcriptomic analysis of caudal oral mucosal swab specimens coupled to detailed medical record linkage of FCGS-affected cats undergoing tooth extractions and in some cases administration of mesenchymal stromal cells (MSCs). To better identify markers of disease and potential response to treatment, the transcriptomes of FCGS-afflicted cats were compared to those of healthy cats and those with chronic periodontitis to clearly establish diagnostic biomarker signal transduction connections. Phosphatidylinositol 3-kinase/Ak strain transforming (PI3K/AKT) and stress-activated protein kinases/Jun N-terminal kinase (SAP/JNK) signaling pathways were significantly differentially regulated in FCGS-afflicted cats. Activation of these pathways also differed in the treatment response groups. In conjunction, the enzymes Caspase 4 (CASP4), matrix metalloproteinase-8 (MMP8), and prostaglandin-endoperoxide synthase 2 (PTGS2) were identified as potential biomarkers for the prediction of treatment response outcomes. The observations in the case study support the use of transcriptomics of FCGS patients to contribute to improved molecular diagnostics for the diagnosis and treatment of FCGS.
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Background: Individual Placement and Support (IPS) is a specialist intervention to help people attain employment in the open competitive labour market. IPS has been developed in severe mental illness and other disabilities, but it is of unknown effectiveness for people with alcohol and drug dependence. The Individual Placement and Support-Alcohol and Drug (IPS-AD) is the first superiority trial to evaluate effectiveness and cost-effectiveness. Methods: IPS-AD was a pragmatic, parallel-group, multi-centre, randomised, controlled, phase 3 trial of standard employment support (treatment-as-usual [TAU]) versus IPS. IPS was offered as a single episode for up to 13 months. The study was done at seven community treatment centres for alcohol and drug dependence in England. Study participants were adults (18-65 years), who had been enrolled for at least 14 days in treatment for alcohol use disorder (AUD), opioid use disorder (OUD), or another drug use disorder (DUD; mostly cannabis and stimulants); were unemployed or economically inactive for at least six months; and wished to attain employment in the open competitive labour market. After random allocation to study interventions, the primary outcome was employment during 18-months of follow-up, analysed by mixed-effects logistic regression, using multiple imputation for the management of missing outcome data. There were two cost-effectiveness outcomes: a health outcome expressed as a quality adjusted life year (QALY) using £30,000 and £70,000 willingness-to-pay [WTP] thresholds; and additional days of employment, with a WTP threshold of £200 per day worked. The study was registered with ISRCTN (ISRCTN24159790) and is completed. Findings: Between 8 May 2018 and 30 September 2019, 2781 potentially eligible patients were identified. 812 were excluded before screening, and 1720 participants were randomly allocated to TAU or IPS. In error, nine participants were randomised to study interventions on two occasions-so data for their first randomisation was analysed (modified intention-to-treat). A further 24 participants withdrew consent for all data to be used (full-analysis set therefore 1687 participants [70.1% male; mean age 40.8 years]; TAU, n = 844; IPS, n = 843 [AUD, n = 610; OUD, n = 837; DUD, n = 240]). Standard employment support was received by 559 [66.2%] of 844 participants in the TAU group. IPS was received by 804 [95.37%] of 843 participants in the IPS group. IPS was associated with an increase in attainment of employment compared with TAU (adjusted odds ratio [OR] 1.29; 95% CI 1.02-1.64; p-value 0.036). IPS was effective for the AUD and DUD groups (OR 1.48; 95% CI 1.14-1.92; p-value 0.004; OR 1.45, 95% CI 1.03-2.04, p-value 0.031, respectively), but not the OUD group. IPS returned an incremental QALY outcome gain of 0.01 (range 0.003-0.02) per participant with no evidence of cost-effectiveness at either WTP threshold-but QALY gains were cost-effective for the AUD and DUD groups at the £70,000 WTP threshold (probability 0.52 and 0.97, respectively). IPS was cost-effective for additional days of employment (probability 0.61), with effectiveness relating to the AUD group only (probability >0.99). Serious Adverse Events were reported by 39 participants (13 [1.5%] of 844 participants in the TAU group and 23 [2.7%] of 43 participants in the IPS group). There was a total of 25 deaths (1.5%; 9 in the TAU group and 16 in the IPS group)-none judged related to study interventions. Interpretation: In this first superiority randomised controlled trial of IPS in alcohol and drug dependence, IPS helped more people attain employment in the open competitive labour market than standard employment support. IPS was cost-effective for a QALY health outcome (£70,000 WTP threshold) for the AUD and DUD groups, and for additional days of employment for the AUD group (£200 per day worked WTP threshold). Funding: UK government Work and Health Unit.
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Methicillin-resistant Staphylococcus aureus (MRSA) is a pervasive and persistent threat that requires the development of novel therapies or adjuvants for existing ones. Aptamers, small single-stranded oligonucleotides that form 3D structures and can bind to target molecules, provide one possible therapeutic route, especially when presented in combination with current antibiotic applications. BALB/c α-1, 3-galactosyltransferase (-/-) knockout (GTKO) mice were infected with MRSA via tail vein IV and subsequently treated with the αSA31 aptamer (n = 4), vancomycin (n = 12), or αSA31 plus vancomycin (n = 12), with split doses in the morning and evening. The heart, lungs, liver, spleen, and kidneys were harvested upon necropsy for histological and qPCR analysis. All mice treated with αSA31 alone died, whereas 5/12 mice treated with vancomycin alone and 7/12 mice treated with vancomycin plus αSA31 survived the course of the experiment. The treatment of MRSA-infected mice with Vancomycin and an adjuvant aptamer αSA31 reduced disease persistence and dispersion as compared to treatment with either vancomycin SA31 alone, indicating the combination of antibiotic and specifically targeted αSA31 aptamer could be a novel way to control MRSA infection. The data further indicate that aptamers may serve as a potential therapeutic option for other emerging antibiotic resistant pathogens.
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The gut microbiome provides the host access to otherwise indigestible nutrients, which are often further metabolized by the microbiome into bioactive components. The gut microbiome can also shift the balance of host-produced compounds, which may alter host health. One precursor to bioactive metabolites is the essential aromatic amino acid tryptophan. Tryptophan is mostly shunted into the kynurenine pathway but is also the primary metabolite for serotonin production and the bacterial indole pathway. Balance between tryptophan-derived bioactive metabolites is crucial for neurological homeostasis and metabolic imbalance can trigger or exacerbate neurological diseases. Alzheimer's, depression, and schizophrenia have been linked to diverging levels of tryptophan-derived anthranilic, kynurenic, and quinolinic acid. Anthranilic acid from collective microbiome metabolism plays a complex but important role in systemic host health. Although anthranilic acid and its metabolic products are of great importance for host-microbe interaction in neurological health, literature examining the mechanistic relationships between microbial production, host regulation, and neurological diseases is scarce and at times conflicting. This narrative review provides an overview of the current understanding of anthranilic acid's role in neurological health and disease, with particular focus on the contribution of the gut microbiome, the gut-brain axis, and the involvement of the three major tryptophan pathways.
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The potential of mesenchymal stem cells (MSCs) for tissue repair and regeneration has garnered great attention. While MSCs are likely to interact with microbes at sites of tissue damage and inflammation, like in the gastrointestinal system, the consequences of pathogenic association on MSC activities have yet to be elucidated. This study investigated the effects of pathogenic interaction on MSC trilineage differentiation paths and mechanisms using model intracellular pathogen Salmonella enterica ssp enterica serotype Typhimurium. The examination of key markers of differentiation, apoptosis, and immunomodulation demonstrated that Salmonella altered osteogenic and chondrogenic differentiation pathways in human and goat adipose-derived MSCs. Anti-apoptotic and pro-proliferative responses were also significantly upregulated (p < 0.05) in MSCs during Salmonella challenge. These results together indicate that Salmonella, and potentially other pathogenic bacteria, can induce pathways that influence both apoptotic response and functional differentiation trajectories in MSCs, highlighting that microbes have a potentially significant role as influencers of MSC physiology and immune activity.
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Two-component systems are ubiquitous signaling mechanisms in bacteria that enable intracellular changes from extracellular cues. These bacterial regulatory systems couple external stimuli to control genetic expression via an autophosphorylation cascade that transduces membrane signals to intracellular locations, thereby allowing bacteria to rapidly adapt to the changing environmental conditions. Well known to control basic cellular processes, it is evident that two-component systems also exercise control over virulence traits, such as motility, secretion systems, and stress responses that impact the complex cascade of networks that alter virulence traits. In the gastrointestinal system, cues for activation of virulence-related two-component systems include metal ions, host-derived metabolites, and gut conditions. The diversity and origin of these cues suggest that the host can exert control over enteric pathogenicity via regulation in the gastrointestinal system. With the rise in multi-drug resistant pathogens, the potential control of pathogenicity with host cues via two-component systems presents a potential alternative to antimicrobials. Though the signaling mechanism itself is well studied, to date there is no systematic review compiling the host-associated cues of two-component systems and virulence traits. This review highlights the direct link between the host gastrointestinal environment and pathogenicity by focusing on two-component systems that are associated with the genetic expression of virulence traits, and that are activated by host-derived cues. The direct link between the host gastrointestinal environment, metabolites, and pathogenicity established in this review both underscores the importance of host-derived cues on bacterial activity and presents an enticing therapeutic target in the fight against antimicrobial resistant pathogens.
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Sinais (Psicologia) , Regulação Bacteriana da Expressão Gênica , Bactérias , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Trato Gastrointestinal/microbiologia , Virulência/genéticaRESUMO
The rumen harbors a complex microbial mixture of archaea, bacteria, protozoa, and fungi that efficiently breakdown plant biomass and its complex dietary carbohydrates into soluble sugars that can be fermented and subsequently converted into metabolites and nutrients utilized by the host animal. While rumen bacterial populations have been well documented, only a fraction of the rumen eukarya are taxonomically and functionally characterized, despite the recognition that they contribute to the cellulolytic phenotype of the rumen microbiota. To investigate how anaerobic fungi actively engage in digestion of recalcitrant fiber that is resistant to degradation, we resolved genome-centric metaproteome and metatranscriptome datasets generated from switchgrass samples incubated for 48 h in nylon bags within the rumen of cannulated dairy cows. Across a gene catalog covering anaerobic rumen bacteria, fungi and viruses, a significant portion of the detected proteins originated from fungal populations. Intriguingly, the carbohydrate-active enzyme (CAZyme) profile suggested a domain-specific functional specialization, with bacterial populations primarily engaged in the degradation of hemicelluloses, whereas fungi were inferred to target recalcitrant cellulose structures via the detection of a number of endo- and exo-acting enzymes belonging to the glycoside hydrolase (GH) family 5, 6, 8, and 48. Notably, members of the GH48 family were amongst the highest abundant CAZymes and detected representatives from this family also included dockerin domains that are associated with fungal cellulosomes. A eukaryote-selected metatranscriptome further reinforced the contribution of uncultured fungi in the ruminal degradation of recalcitrant fibers. These findings elucidate the intricate networks of in situ recalcitrant fiber deconstruction, and importantly, suggest that the anaerobic rumen fungi contribute a specific set of CAZymes that complement the enzyme repertoire provided by the specialized plant cell wall degrading rumen bacteria.
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Fungos/metabolismo , Proteoma , Rúmen/microbiologia , Anaerobiose , Animais , Bovinos , Feminino , Fungos/genética , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Proteoma/metabolismo , Rúmen/metabolismoRESUMO
Cyanobacteria are found in most illuminated environments and are key players in global carbon and nitrogen cycling. Although significant efforts have been made to advance our understanding of this important phylum, still little is known about how members of the cyanobacteria affect and respond to changes in complex biological systems. This lack of knowledge is in part due to our dependence on pure cultures when determining the metabolism and function of a microorganism. We took advantage of the Culture Collection of Microorganisms from Extreme Environments (CCMEE), a collection of more than 1,000 publicly available photosynthetic co-cultures maintained at the Pacific Northwest National Laboratory, and assessed via 16S rRNA amplicon sequencing if samples readily available from public culture collection could be used in the future to generate new insights into the role of microbial communities in global and local carbon and nitrogen cycling. Results from this work support the existing notion that culture depositories in general hold the potential to advance fundamental and applied research. Although it remains to be seen if co-cultures can be used at large scale to infer roles of individual organisms, samples that are publicly available from existing co-cultures depositories, such as the CCMEE, might be an economical starting point for such studies. Access to archived biological samples, without the need for costly field work, might in some circumstances be one of the few remaining ways to advance the field and to generate new insights into the biology of ecosystems that are not easily accessible. The current COVID-19 pandemic, which makes sampling expeditions almost impossible without putting the health of the participating scientists on the line, is a very timely example.
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Anaerobic fungi (AF) play an essential role in feed conversion due to their potent fiber degrading enzymes and invasive growth. Much has been learned about this unusual fungal phylum since the paradigm shifting work of Colin Orpin in the 1970s, when he characterized the first AF. Molecular approaches targeting specific phylogenetic marker genes have facilitated taxonomic classification of AF, which had been previously been complicated by the complex life cycles and associated morphologies. Although we now have a much better understanding of their diversity, it is believed that there are still numerous genera of AF that remain to be described in gut ecosystems. Recent marker-gene based studies have shown that fungal diversity in the herbivore gut is much like the bacterial population, driven by host phylogeny, host genetics and diet. Since AF are major contributors to the degradation of plant material ingested by the host animal, it is understandable that there has been great interest in exploring the enzymatic repertoire of these microorganisms in order to establish a better understanding of how AF, and their enzymes, can be used to improve host health and performance, while simultaneously reducing the ecological footprint of the livestock industry. A detailed understanding of AF and their interaction with other gut microbes as well as the host animal is essential, especially when production of affordable high-quality protein and other animal-based products needs to meet the demands of an increasing human population. Such a mechanistic understanding, leading to more sustainable livestock practices, will be possible with recently developed -omics technologies that have already provided first insights into the different contributions of the fungal and bacterial population in the rumen during plant cell wall hydrolysis.
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BACKGROUND AND OBJECTIVES: Cognitively impaired individuals are at increased risk for functional and behavioral difficulties at mealtimes, leading to compromised eating performance, low food and fluid intake, and negative functional and nutritional outcomes. Nursing assistants are the most critical front-line care staff and best positioned to manage the personal and environmental factors that influence resident eating performance. Identifying nursing assistants' perceptions of barriers and facilitators to engaging residents in eating will provide important experientially based foundation for developing and testing evidence-driven interventions to promote mealtime care. METHODS: A qualitative descriptive study was conducted in three sites: two nursing homes and one hospital gero-psychiatric inpatient unit. Six focus groups were conducted with a purposive sample of 23 nursing assistants who regularly provided mealtime care to residents with cognitive impairment. Interview questions addressed barriers and facilitators at resident, caregiver, environmental (facility), and policy levels in optimizing mealtime care. Audio recordings of focus groups were transcribed and analyzed using qualitative descriptive content analysis. Both barriers and facilitators were organized into a hierarchical taxonomy based on similarities and differences framed by the Social Ecological Model. RESULTS: The majority of barriers and facilitators were at the caregiver level. Caregiver-level barriers included lack of preparation and training, competing work demands, time pressure, and frustration. Caregiver-level facilitators included caregiver preparation and motivational, technical, informational, and instrumental assistance. Environmental-level barriers and facilitators related to the physical, social, and cultural environment and facility practices. Only barriers to optimizing mealtime care were identified at resident and policy levels. CONCLUSIONS: Nursing assistants identified multilevel barriers as well as a wide range of caregiver and environmental facilitators to optimizing dementia mealtime care. Findings can inform the development and implementation of multifaceted innovative mealtime assistance and staff training programs to promote resident eating performance while fostering person-centered individualized mealtime care practice.
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Demência , Ingestão de Alimentos , Assistentes de Enfermagem , Idoso , Humanos , Refeições , Assistentes de Enfermagem/psicologia , Casas de Saúde , Pesquisa QualitativaRESUMO
Attempts to alter intestinal dysbiosis via administration of probiotics have consistently shown that colonization with the administered microbes is transient. This study sought to determine whether provision of an initial course of Bifidobacterium longum subsp. infantis (B. infantis) would lead to persistent colonization of the probiotic organism in breastfed infants. Mothers intending to breastfeed were recruited and provided with lactation support. One group of mothers fed B. infantis EVC001 to their infants from day 7 to day 28 of life (n = 34), and the second group did not administer any probiotic (n = 32). Fecal samples were collected during the first 60 postnatal days in both groups. Fecal samples were assessed by 16S rRNA gene sequencing, quantitative PCR, mass spectrometry, and endotoxin measurement. B. infantis-fed infants had significantly higher populations of fecal Bifidobacteriaceae, in particular B. infantis, while EVC001 was fed, and this difference persisted more than 30 days after EVC001 supplementation ceased. Fecal milk oligosaccharides were significantly lower in B. infantis EVC001-fed infants, demonstrating higher consumption of human milk oligosaccharides by B. infantis EVC001. Concentrations of acetate and lactate were significantly higher and fecal pH was significantly lower in infants fed EVC001, demonstrating alterations in intestinal fermentation. Infants colonized by Bifidobacteriaceae at high levels had 4-fold-lower fecal endotoxin levels, consistent with observed lower levels of Gram-negative Proteobacteria and Bacteroidetes. IMPORTANCE The gut microbiome in early life plays an important role for long-term health and is shaped in large part by diet. Probiotics may contribute to improvements in health, but they have not been shown to alter the community composition of the gut microbiome. Here, we found that breastfed infants could be stably colonized at high levels by provision of B. infantis EVC001, with significant changes to the overall microbiome composition persisting more than a month later, whether the infants were born vaginally or by caesarean section. This observation is consistent with previous studies demonstrating the capacity of this subspecies to utilize human milk glycans as a nutrient and underscores the importance of pairing a probiotic organism with a specific substrate. Colonization by B. infantis EVC001 resulted in significant changes to fecal microbiome composition and was associated with improvements in fecal biochemistry. The combination of human milk and an infant-associated Bifidobacterium sp. shows, for the first time, that durable changes to the human gut microbiome are possible and are associated with improved gut function.
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BACKGROUND AND PURPOSE: Sleep hygiene is one factor that contributes to poor sleep in breast cancer survivors but is poorly measured. The purposes of this study were to (a) evaluate the psychometric properties of the Sleep Hygiene Awareness and Practice Scale (SHAPS) and (b) compare SHAPS scores between midlife women with and without breast cancer. METHODS: Cross-sectional, descriptive data from a single-blinded, controlled hot flash intervention trial. RESULTS: 194 women (88 breast cancer survivors; 106 menopausal women). Reliability of the three sections of the SHAPS was inadequate with Cronbach's alphas ranging from 0.23 to 0.67. Sleep hygiene practices were modestly correlated with global sleep quality in both groups. CONCLUSIONS: Findings suggest the SHAPS would need to be revised to be a psychometrically sound measure of sleep hygiene awareness and practice.