Mucosa-associated biohydrogenating microbes protect the simulated colon microbiome from stress associated with high concentrations of poly-unsaturated fat

Polyunsaturated fatty acids (PUFAs) may affect colon microbiome homeostasis by exerting (specific) antimicrobial effects and/or interfering with mucosal biofilm formation at the gut mucosal interface. We used standardized batch incubations and the Mucosal-Simulator of the Human Microbial Intestinal Ecosystem (M-SHIME) to show the in vitro luminal and mucosal effects of the main PUFA in the Western diet, linoleic acid (LA). High concentrations of LA were found to decrease butyrate production and Faecalibacterium prausnitzii numbers dependent on LA biohydrogenation to vaccenic acid (VA) and stearic acid (SA). In faecal batch incubations, LA biohydrogenation and butyrate production were positively correlated and SA did not inhibit butyrate production. In the M-SHIME, addition of a mucosal environment stimulated biohydrogenation to SA and protected F. prausnitzii from inhibition by LA. This was probably due to the preference of two biohydrogenating genera Roseburia and Pseudobutyrivibrio for the mucosal niche. Co-culture batch incubations using Roseburia hominis and F. prausnitzii validated these observations. Correlations networks further uncovered the central role of Roseburia and Pseudobutyrivibrio in protecting luminal and mucosal SHIME microbiota from LA-induced stress. Our results confirm how cross-shielding interactions provide resilience to the microbiome and demonstrate the importance of biohydrogenating, mucosal bacteria for recovery from LA stress.

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Genome-centric resolution of microbial diversity, metabolism and interactions in anaerobic digestion

Our understanding of the complex interconnected processes performed by microbial communities is hindered by our inability to culture the vast majority of microorganisms. Metagenomics provides a way to bypass this cultivation bottleneck and recent advances in this field now allow us to recover a growing number of genomes representing previously uncultured populations from increasingly complex environments. In this study, a temporal genomecentric metagenomic analysis was performed of lab-scale anaerobic digesters that host complex microbial communities fulfilling a series of interlinked metabolic processes to enable the conversion of cellulose to methane. In total, 101 population genomes that were moderate to near-complete were recovered based primarily on differential coverage binning. These populations span 19 phyla, represent mostly novel species and expand the genomic coverage of several rare phyla. Classification into functional guilds based on their metabolic potential revealed metabolic networks with a high level of functional redundancy as well as niche specialization, and allowed us to identify potential roles such as hydrolytic specialists for several rare, uncultured populations. Genome-centric analyses of complex microbial communities across diverse environments provide the key to understanding the phylogenetic and metabolic diversity of these interactive communities.

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Successful strategy to treat a solitary cystic melanoma brain metastasis

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Perspectives for microbial community composition in anaerobic digestion : from abundance and activity to connectivity

Microbial management in anaerobic digestion is mainly focused on physically present and metabolically active species. Because of its complexity and operation near the thermodynamic equilibria, it is equally important to address functional regulation, based on spatial organisation and interspecies communication. Further establishment of the knowledge on microbial communication in anaerobic digestion through quorum sensing and nanowires is needed. Methods to detect centres of concentrated activity, related to the presence of highly active and well-connected species that take a central role in the anaerobic digestion process, have to be optimized. Bioaugmentation could serve as a crucial tool to introduce keystone species that may create or sustain such centres. Functional stability can be maintained by keeping the microbial community active. This results in a clear trade-off between functionally active and redundant microorganisms as primary basis for microbial community organization. Finally, a microbial community based prediction strategy for advanced process control is formulated.

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Association of Modified Frailty Index Score With Perioperative Risk for Patients Undergoing Total Laryngectomy.

Association of Modified Frailty Index Score With Perioperative Risk for Patients Undergoing Total Laryngectomy.

JAMA Otolaryngol Head Neck Surg. 2017 Jun 08;:

Authors: Wachal B, Johnson M, Burchell A, Sayles H, Rieke K, Lindau R, Lydiatt W, Panwar A

Abstract
Importance: Objective preoperative risk assessment tools, such as the Modified Frailty Index (mFI), may inform patient and physician decision making when considering total laryngectomy. Estimation of outcomes may help to set realistic expectations about recovery and outcomes and facilitate optimal resource management.
Objective: To evaluate the association between the mFI score as a measure of frailty and outcomes following total laryngectomy.
Design, Setting, and Participants: Retrospective evaluation using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP), a risk- and case-mix-adjusted national quality assessment program. The ACS NSQIP database identified 595 patients who underwent total laryngectomy between 2006 and 2012. Patients were assessed for demographics and comorbidity and were stratified on the basis of calculated mFI score. Outcomes, including postoperative complications, length of hospitalization, and discharge destination, were evaluated as a function of increasing frailty using multivariable logistic regression and Cox proportional hazards regression models.
Main Outcomes and Measures: Risk of postoperative complications, length of hospitalization, and discharge disposition.
Results: After exclusion of patients who experienced significant deviation from standard care protocols and those with missing or incomplete data, 343 individuals were included in the analysis. Of these, 278 (81.0%) were men, and the mean age was 63 years (95% CI, 61.9-64.4 years). Increasing frailty resulted in a nonlinear but progressive rise in incidence of postoperative adverse events. Overall, 96 (28.0%) patients experienced a postoperative complication, and patients with an mFI score of 3 or higher were more likely to develop postoperative complications than were patients with an mFI score of 0 (50.0% vs 16.7%; OR, 3.83; 95% CI, 1.72- 8.51). Patients in the highest frailty group experienced a longer mean duration of hospitalization (14.2 vs 9.5 days; difference, 4.7; 95% CI, 1.3-8.1 days) and were more likely to require skilled care after discharge (33.3% vs 3.2%; difference, 30.1%; 95% CI, 7.4%-52.9%).
Conclusions and Relevance: An mFI score of 3 or higher is associated with increased risk for postoperative complications, longer hospitalization, and need for postdischarge skilled care following total laryngectomy. The mFI provides a personalized risk assessment to better inform patients, physicians, and payers when planning a total laryngectomy.

PMID: 28594992 [PubMed - as supplied by publisher]

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Cognitive Training Program to Treat Tinnitus.

Cognitive Training Program to Treat Tinnitus.

JAMA Otolaryngol Head Neck Surg. 2017 Jun 08;:

Authors: Stevelink R

PMID: 28594988 [PubMed - as supplied by publisher]

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Cognitive Training Program to Treat Tinnitus-Reply.

Cognitive Training Program to Treat Tinnitus-Reply.

JAMA Otolaryngol Head Neck Surg. 2017 Jun 08;:

Authors: Kallogjeri D, Piccirillo JF

PMID: 28594981 [PubMed - as supplied by publisher]

http://ift.tt/2t1TTxU