Neonates are at high risk for central line associated bloodstream infections (CLABSI). Biofilm formation is universal on indwelling catheters but why some biofilms seed the bloodstream to cause ...CLABSI is not clearly understood. With the objective to test the hypothesis that catheter biofilm microbiome in neonates with CLABSI differs than those without infection, we prospectively enrolled neonates (n = 30) with infected and uninfected indwelling central catheters. Catheters were collected at the time of removal, along with blood samples and skin swabs at the catheter insertion sites. Microbiomes of catheter biofilms, skin swabs and blood were evaluated by profiling the V4 region of the bacterial 16S rRNA gene using Illumina MiSeq sequencing platform. The microbial DNA load was higher from catheter biofilms of CLABSI patients without differences in alpha diversity when compared to that of the non-CLABSI neonates. Proteus and unclassified Staphylococcaceae were more abundant in infected catheter biofilms while Bradyrhizobium, Cloacibacterium, and Sphingomonas were more abundant in the uninfected catheters. A blood microbiome was detected in uninfected samples. The blood microbiome in CLABSI neonates clustered separately from the uninfected blood samples in beta diversity plots. We found that the microbiome signature in catheter biofilm and blood of neonates with CLABSI is different than the microbiomes of non-CLABSI neonates.
Gut microbiome in adolescent depression Thapa, Santosh; Sheu, Jessica C.; Venkatachalam, Alamelu ...
Journal of affective disorders,
09/2021, Letnik:
292
Journal Article
Recenzirano
Odprti dostop
•The role of the microbiome-gut-brain axis in psychopathology is gaining attention.•Adolescents with and without major depression showed no gut microbiome differences.•Also, no significant effect of ...selective serotonin reuptake inhibitors was found.
To examine the association of major depressive disorder (MDD) and selective serotonin reuptake inhibitor (SSRI) use with gut microbiome in older adolescents and younger adults.
Fifteen to 20-year-old participants within a month of starting an SSRI and unmedicated controls were enrolled in a longitudinal study. They underwent a diagnostic evaluation comprising self-completed and rater-administered questionnaires and clinical interview. They also provided a stool sample, which was stored at -80°C until DNA extraction. Microbial DNA was extracted with the MoBio PowerSoil kit, and the V4 region of the 16S rRNA was amplified and sequenced. Raw sequence data was processed with the LotuS pipeline. Only samples with no antibiotic exposure in the last 6 months and with >1000 quality filtered reads were included in the analysis.
160 participants (57.5% female, mean age 20.0±1.9 years, 29% taking SSRIs) were enrolled, comprising 110 MDD patients (60% in acute episode), 27 healthy controls, and 23 psychiatric controls. No significant group differences were observed in bacterial richness or alpha and beta diversity. Differential abundance analysis of bacterial taxa found no significant group differences at the phylum and genus levels. Neither being in a major depressive episode vs. remission nor using SSRIs was associated with differential bacterial composition.
In this sizeable sample of older adolescents, neither MDD nor SSRI use was associated with differences in gut bacterial microbiome. In this age group, the bi-directional interaction between the gut bacteria and brain may be more nuanced than in adults, requiring further investigation.
Gastrointestinal problems affect the health and quality of life of individuals with Rett syndrome (RTT) and pose a medical hardship for their caregivers. We hypothesized that the variability in the ...RTT phenotype contributes to the dysbiosis of the gut microbiome and metabolome in RTT, predisposing these individuals to gastrointestinal dysfunction.
We characterized the gut bacterial microbiome and metabolome in girls and young women with RTT (n = 44) and unaffected controls (n = 21), and examined the relation between the composition of the microbiome and variations in the RTT phenotype.
Demographics and clinical information, including growth and anthropometric measurements, pubertal status, symptoms, clinical severity score, bowel movement, medication use, and dietary intakes were collected from the participants. Fecal samples were collected for analysis of the gut microbiome using Illumina MiSeq-based next-generation sequencing of the 16S rRNA gene followed by bioinformatics analysis of microbial composition, diversity, and community structure. Selected end-products of microbial protein metabolism were characterized by liquid chromatography-mass spectrometry.
The gut bacterial microbiome differed within the RTT cohort based on pubertal status (p<0.02) and clinical severity scores (p<0.02) of the individuals and the type of diet (p<0.01) consumed. Although the composition of the gut microbiome did not differ between RTT and unaffected individuals, concentrations of protein end-products of the gut bacterial metabolome, including γ-aminobutyric acid (GABA) (p<0.001), tyrosine (p<0.02), and glutamate (p<0.06), were lower in the RTT cohort. Differences in the microbiome within RTT groups, based on symptomatic anxiety, hyperventilation, abdominal distention, or changes in stool frequency and consistency, were not detected.
Although variability in the RTT phenotype contributes to the dysbiosis of the gut microbiome, we presently cannot infer causality between gut bacterial dysbiosis and gastrointestinal dysfunction. Nevertheless, alterations in the gut metabolome may provide clues to the pathophysiology of gastrointestinal problems in RTT.
Accumulating studies have defined a role for the intestinal microbiota in modulation of host behavior. Research using gnotobiotic mice emphasizes that early microbial colonization with a complex ...microbiota (conventionalization) can rescue some of the behavioral abnormalities observed in mice that grow to adulthood completely devoid of bacteria (germ-free mice). However, the human infant and adult microbiomes vary greatly, and effects of the neonatal microbiome on neurodevelopment are currently not well understood. Microbe-mediated modulation of neural circuit patterning in the brain during neurodevelopment may have significant long-term implications that we are only beginning to appreciate. Modulation of the host central nervous system by the early-life microbiota is predicted to have pervasive and lasting effects on brain function and behavior. We sought to replicate this early microbe-host interaction by colonizing gnotobiotic mice at the neonatal stage with a simplified model of the human infant gut microbiota. This model consortium consisted of four "infant-type" Bifidobacterium species known to be commensal members of the human infant microbiota present in high abundance during postnatal development. Germ-free mice and mice neonatally-colonized with a complex, conventional murine microbiota were used for comparison. Motor and non-motor behaviors of the mice were tested at 6-7 weeks of age, and colonization patterns were characterized by 16S ribosomal RNA gene sequencing. Adult germ-free mice were observed to have abnormal memory, sociability, anxiety-like behaviors, and motor performance. Conventionalization at the neonatal stage rescued these behavioral abnormalities, and mice colonized with Bifidobacterium spp. also exhibited important behavioral differences relative to the germ-free controls. The ability of Bifidobacterium spp. to improve the recognition memory of both male and female germ-free mice was a prominent finding. Together, these data demonstrate that the early-life gut microbiome, and human "infant-type" Bifidobacterium species, affect adult behavior in a strongly sex-dependent manner, and can selectively recapitulate the results observed when mice are colonized with a complex microbiota.
Background & Aims Emerging data on the gut microbiome in autism spectrum disorder (ASD) suggest that altered host–microbe interactions may contribute to disease symptoms. Although gut microbial ...communities in children with ASD are reported to differ from individuals with neurotypical development, it is not known whether these bacteria induce pathogenic neuroimmune signals. Methods Because commensal clostridia interactions with the intestinal mucosa can regulate disease-associated cytokine and serotonergic pathways in animal models, we evaluated whether microbiome-neuroimmune profiles (from rectal biopsy specimens and blood) differed in ASD children with functional gastrointestinal disorders (ASD-FGID, n = 14) compared with neurotypical (NT) children with FGID (NT-FGID, n = 15) and without abdominal pain (NT, n = 6). Microbial 16S ribosomal DNA community signatures, cytokines, and serotonergic metabolites were quantified and correlated with gastrointestinal symptoms. Results A significant increase in several mucosa-associated Clostridiales was observed in ASD-FGID, whereas marked decreases in Dorea and Blautia , as well as Sutterella , were evident. Stratification by abdominal pain showed multiple organisms in ASD-FGID that correlated significantly with cytokines (interleukin IL6, IL1, IL17A, and interferon-γ). Group comparisons showed that IL6 and tryptophan release by mucosal biopsy specimens was highest in ASD children with abdominal pain, whereas serotonergic metabolites generally were increased in children with FGIDs. Furthermore, proinflammatory cytokines correlated significantly with several Clostridiales previously reported to associate with ASD, as did tryptophan and serotonin. Conclusions Our findings identify distinctive mucosal microbial signatures in ASD children with FGID that correlate with cytokine and tryptophan homeostasis. Future studies are needed to establish whether these disease-associated Clostridiales species confer early pathogenic signals in children with ASD and FGID.
Background
Hispanic people with cystic fibrosis (CF) have decreased life expectancy and earlier acquisition of Pseudomonas aeruginosa compared to non‐Hispanic white individuals with CF. Racial and ...ethnic differences in the airway microbiome of CF may contribute to known health disparity, but have not been studied. The objective was to describe differences in the upper airway microbial community in Hispanic and non‐Hispanic white children with CF.
Methods
This prospective, observational cohort study of 59 Hispanic and non‐Hispanic white children with CF, ages 2−10 years old, was performed at Texas Children's Hospital (TCH) from February 2019 to January 2020. Oropharyngeal swabs were collected from the cohort during clinic visit. Swab samples underwent sequencing (16S V4 rRNA), diversity analysis, and taxonomic profiling. Key demographic and clinical data were collected from the electronic medical record and the CF Foundation Patient Registry (CFFPR). Statistical analysis compared sequencing, demographic, and clinical data.
Results
We found no significant difference in Shannon diversity or relative abundance of bacterial phyla between Hispanic and non‐Hispanic children with CF. However, a low abundant taxa‐ “uncultured bacterium” belonging to the order Saccharimonadales was significantly higher in Hispanic children (mean relative abundance = 0.13%) compared to the non‐Hispanic children (0.03%). Hispanic children had increased incidence of P. aeruginosa (p = 0.045) compared to non‐Hispanic children.
Conclusion
We did not find a significant difference in the airway microbial diversity between Hispanic and non‐Hispanic white children with CF. However, we found a greater relative abundance of Saccharimonadales and higher incidence of P. aeruginosa in Hispanic children with CF.
Hospital-acquired infections pose significant costly global challenges to patient care. Rapid and sensitive methods to identify potential outbreaks are integral to infection control measures. ...Whole-genome sequencing (WGS)-based bacterial strain typing provides higher discriminatory power over standard nucleotide banding pattern–based methods such as repetitive sequence-based PCR (rep-PCR). However, integration of WGS into clinical epidemiology is limited by the lack of consensus in methodology and data analysis/interpretation. In this study, WGS was performed on genomic DNA extracted from 22 multidrug-resistant Pseudomonas aeruginosa (MDR-PA) isolates using next-generation sequencing. Resulting high-quality reads were analyzed for phylogenetic relatedness using a whole-genome multilocus sequence typing (wgMLST)-based software program and single-nucleotide variant phylogenomics (SNVPhyl). WGS-based results were compared with conventional MLST and archived rep-PCR results. Rep-PCR identified three independent clonal clusters of MDR-PA. Only one clonal cluster identified by rep-PCR, an endemic strain within the pediatric cystic fibrosis population at Texas Children's Hospital, was concordantly identified using wgMLST and SNVPhyl. Results were highly consistent between the three sequence-based analyses (conventional MLST, wgMLST, and SNVPhyl), and these results remained consistent with the addition of 74 MDR-PA genomes. These WGS-based methods provided greater resolution for strain discrimination than rep-PCR or standard MLST classification, and the ease of use of wgMLST software renders it clinically viable for analysis, interpretation, and reporting of WGS-based strain typing.
Hypervirulent disease due to group A Streptococcus (GAS) can result from strains with mutations that enhance virulence gene expression but reduce subsequent transmission. We used whole-genome ...sequencing to investigate intrafamilial spread among 4 siblings of infection due to a hypervirulent GAS strain that resulted in a fatality. All invasive and pharyngeal GAS isolates had an identical mutation in a gene encoding a key regulatory protein that yielded a hyperinvasive phenotype. These data challenge the prevailing theory of reduced transmission induced by mutations that lead to hypervirulent GAS by showing that spread of hypervirulent GAS may lead to clusters of invasive disease.
Ambulatory staffing to workload based on visit volume in an outpatient setting is an elusive formula, and the literature describing such processes is limited. One health system tasked a ...multidisciplinary team with developing an ambulatory staffing to workload tool to meet the needs of staff, management, and leadership. The resultant tool includes an automated dashboard for determining staffing needs on the basis of quantified workload, prospective modeling, and historical dashboards to demonstrate actual staffing (full-time equivalents) to workload (outpatient volumes) compared with budget.
Global estimations of 4 billion people living on plant-based diets signify tremendous diversity in plant consumption and their assorted miRNAs, which presents a challenging model to experimentally ...address how plant-based miRNAs impact the microbiome. Here we establish baseline gut microbiome composition for a mouse model deficient in the specific mammalian miR-146a shown to alter gut microbiomes. We then asses the effect on the gut microbiome when miR-146a-deficient mice are fed a transgenic plant-based diet expressing the murine-derived miR-146a. Mice deficient in miR-146a were maintained either on a baseline diet until 7 weeks of age (day 0) and then fed either vector or miR-146a-expressing plant-based diets for 21 days. The gut microbiomes of mice were examined by comparing the V4 region of 16S rRNA gene sequences of DNA isolated from fecal samples at days 0 (baseline diet) and 21 (vector or miR-146a expressing plant-based diets).
Beta-diversity analysis demonstrated that the transition from baseline chow to a plant-based diet resulted in significant longitudinal shifts in microbial community structure attributable to increased fiber intake. Bipartite network analysis suggests that miR-146a-deficient mice fed a plant diet rich in miR-146a have a microbiome population modestly different than mice fed an isogenic control plant diet deficient in miR-146a.
A mouse diet composed of a transgenic plant expressing a mouse miR-146a may fine tune microbial communities but does not appear to have global effects on microbiome structure and composition.