HERV1-env Induces Unfolded Protein Response Activation in Autoimmune Liver Disease: A Potential Mechanism for Regulatory T Cell Dysfunction.

Regulatory T cells (Tregs) are not terminally differentiated but can acquire effector properties. Here we report an increased expression of human endogenous retrovirus 1 (HERV1-env) proteins in Tregs of patients with de novo autoimmune hepatitis and autoimmune hepatitis, which induces endoplasmic reticulum (ER) stress. HERV1-env-triggered ER stress activates all three branches (IRE1, ATF6, and PERK) of the unfolded protein response (UPR). Our coimmunoprecipitation studies show an interaction between HERV1-env proteins and the ATF6 branch of the UPR. The activated form of ATF6α activates the expression of RORC and STAT3 by binding to promoter sequences and induces IL-17A production. Silencing of HERV1-env results in recovery of Treg suppressive function. These findings identify ER stress and UPR activation as key factors driving Treg plasticity (species: human).

Skin colonization by circulating neoplastic clones in cutaneous T-cell lymphoma.

Mycosis fungoides (MF) is a mature T-cell lymphoma currently thought to develop primarily in the skin by a clonal expansion of a transformed, resident memory T cell. However, this concept does not explain the key characteristics of MF, such as the debut with multiple, widespread skin lesions or inability of skin-directed therapies to provide cure. The testable inference of the mature T-cell theory is the clonality of MF with respect to all rearranged T-cell receptor (TCR) genes. Here, we used a whole-exome sequencing approach to detect and quantify TCR-α, ß, and γ clonotypes in tumor cell clusters microdissected from MF lesions. This method allowed us to calculate the tumor cell fraction of the sample and therefore an unequivocal identification of the TCR clonotypes as neoplastic. Analysis of TCR sequences from 29 patients with MF stage I to IV proved the existence of multiple T-cell clones within the tumor cell fraction, with a considerable variation between patients and between lesions from the same patient (median, 11 clones; range, 2-80 clones/sample). We have also detected multiple neoplastic clones in the peripheral blood in all examined patients. Based on these findings, we propose that circulating neoplastic T-cell clones continuously replenish the lesions of MF, thus increasing their heterogeneity by a mechanism analogous to the consecutive tumor seeding. We hypothesize that circulating neoplastic clones might be a promising target for therapy and could be exploited as a potential biomarker in MF.

Impact of sequencing depth and technology on de novo RNA-Seq assembly.

BACKGROUND: RNA-Seq data is inherently nonuniform for different transcripts because of differences in gene expression. This makes it challenging to decide how much data should be generated from each sample. How much should one spend to recover the less expressed transcripts? The sequencing technology used is another consideration, as there are inevitably always biases against certain sequences. To investigate these effects, we first looked at high-depth libraries from a set of well-annotated organisms to ascertain the impact of sequencing depth on de novo assembly. We then looked at libraries sequenced from the Universal Human Reference RNA (UHRR) to compare the performance of Illumina HiSeq and MGI DNBseq™ technologies. RESULTS: On the issue of sequencing depth, the amount of exomic sequence assembled plateaued using data sets of approximately 2 to 8 Gbp. However, the amount of genomic sequence assembled did not plateau for many of the analyzed organisms. Most of the unannotated genomic sequences are single-exon transcripts whose biological significance will be questionable for some users. On the issue of sequencing technology, both of the analyzed platforms recovered a similar number of full-length transcripts. The missing "gap" regions in the HiSeq assemblies were often attributed to higher GC contents, but this may be an artefact of library preparation and not of sequencing technology. CONCLUSIONS: Increasing sequencing depth beyond modest data sets of less than 10 Gbp recovers a plethora of single-exon transcripts undocumented in genome annotations. DNBseq™ is a viable alternative to HiSeq for de novo RNA-Seq assembly.

Effect of Oral Capsule- vs Colonoscopy-Delivered Fecal Microbiota Transplantation on Recurrent Clostridium difficile Infection: A Randomized Clinical Trial.

Importance: Fecal microbiota transplantation (FMT) is effective in preventing recurrent Clostridium difficile infection (RCDI). However, it is not known whether clinical efficacy differs by route of delivery. Objective: To determine whether FMT by oral capsule is noninferior to colonoscopy delivery in efficacy. Design, Setting, and Participants: Noninferiority, unblinded, randomized trial conducted in 3 academic centers in Alberta, Canada. A total of 116 adult patients with RCDI were enrolled between October 2014 and September 2016, with follow-up to December 2016. The noninferiority margin was 15%. Interventions: Participants were randomly assigned to FMT by capsule or by colonoscopy at a 1:1 ratio. Main Outcomes and Measures: The primary outcome was the proportion of patients without RCDI 12 weeks after FMT. Secondary outcomes included (1) serious and minor adverse events, (2) changes in quality of life by the 36-Item Short Form Survey on a scale of 0 (worst possible quality of life) to 100 (best quality of life), and (3) patient perception on a scale of 1 (not at all unpleasant) to 10 (extremely unpleasant) and satisfaction on a scale of 1 (best) to 10 (worst). Results: Among 116 patients randomized (mean [SD] age, 58 [19] years; 79 women [68%]), 105 (91%) completed the trial, with 57 patients randomized to the capsule group and 59 to the colonoscopy group. In per-protocol analysis, prevention of RCDI after a single treatment was achieved in 96.2% in both the capsule group (51/53) and the colonoscopy group (50/52) (difference, 0%; 1-sided 95% CI, -6.1% to infinity; P < .001), meeting the criterion for noninferiority. One patient in each group died of underlying cardiopulmonary illness unrelated to FMT. Rates of minor adverse events were 5.4% for the capsule group vs 12.5% for the colonoscopy group. There was no significant between-group difference in improvement in quality of life. A significantly greater proportion of participants receiving capsules rated their experience as "not at all unpleasant" (66% vs 44%; difference, 22% [95% CI, 3%-40%]; P = .01). Conclusions and Relevance: Among adults with RCDI, FMT via oral capsules was not inferior to delivery by colonoscopy for preventing recurrent infection over 12 weeks. Treatment with oral capsules may be an effective approach to treating RCDI. Trial Registration: clinicaltrials.gov Identifier: NCT02254811.

SOAPdenovo-Trans: de novo transcriptome assembly with short RNA-Seq reads.

MOTIVATION: Transcriptome sequencing has long been the favored method for quickly and inexpensively obtaining a large number of gene sequences from an organism with no reference genome. Owing to the rapid increase in throughputs and decrease in costs of next- generation sequencing, RNA-Seq in particular has become the method of choice. However, the very short reads (e.g. 2 × 90 bp paired ends) from next generation sequencing makes de novo assembly to recover complete or full-length transcript sequences an algorithmic challenge. RESULTS: Here, we present SOAPdenovo-Trans, a de novo transcriptome assembler designed specifically for RNA-Seq. We evaluated its performance on transcriptome datasets from rice and mouse. Using as our benchmarks the known transcripts from these well-annotated genomes (sequenced a decade ago), we assessed how SOAPdenovo-Trans and two other popular transcriptome assemblers handled such practical issues as alternative splicing and variable expression levels. Our conclusion is that SOAPdenovo-Trans provides higher contiguity, lower redundancy and faster execution. AVAILABILITY AND IMPLEMENTATION: Source code and user manual are available at http://sourceforge.net/projects/soapdenovotrans/.

Modeling the yew tree tubulin and a comparison of its interaction with paclitaxel to human tubulin.

PURPOSE: To explore possible ways in which yew tree tubulin is naturally resistant to paclitaxel. While the yew produces a potent cytotoxin, paclitaxel, it is immune to paclitaxel's cytotoxic action. METHODS: Tubulin sequence data for plant species were obtained from Alberta 1000 Plants Initiative. Sequences were assembled with Trinity de novo assembly program and tubulin identified. Homology modeling using MODELLER software was done to generate structures for yew tubulin. Molecular dynamics simulations and molecular mechanics Poisson-Boltzmann calculations were performed with the Amber package to determine binding affinity of paclitaxel to yew tubulin. ClustalW2 program and PHYLIP package were used to perform phylogenetic analysis on plant tubulin sequences. RESULTS: We specifically analyzed several important regions in tubulin structure: the high-affinity paclitaxel binding site, as well as the intermediate binding site and microtubule nanopores. Our analysis indicates that the high-affinity binding site contains several substitutions compared to human tubulin, all of which reduce the binding energy of paclitaxel. CONCLUSIONS: The yew has achieved a significant reduction of paclitaxel's affinity for its tubulin by utilizing several specific residue changes in the binding pocket for paclitaxel.

Metagenomics Versus Metatranscriptomics of the Murine Gut Microbiome for Assessing Microbial Metabolism During Inflammation.

Shotgun metagenomics studies have improved our understanding of microbial population dynamics and have revealed significant contributions of microbes to gut homeostasis. They also allow in silico inference of the metagenome. While they link the microbiome with metabolic abnormalities associated with disease phenotypes, they do not capture microbial gene expression patterns that occur in response to the multitude of stimuli that constantly ambush the gut environment. Metatranscriptomics closes that gap, but its implementation is more expensive and tedious. We assessed the metabolic perturbations associated with gut inflammation using shotgun metagenomics and metatranscriptomics. Shotgun metagenomics detected changes in abundance of bacterial taxa known to be SCFA producers, which favors gut homeostasis. Bacteria in the phylum Firmicutes were found at decreased abundance, while those in phyla Bacteroidetes and Proteobacteria were found at increased abundance. Surprisingly, inferring the coding capacity of the microbiome from shotgun metagenomics data did not result in any statistically significant difference, suggesting functional redundancy in the microbiome or poor resolution of shotgun metagenomics data to profile bacterial pathways, especially when sequencing is not very deep. Obviously, the ability of metatranscriptomics libraries to detect transcripts expressed at basal (or simply low) levels is also dependent on sequencing depth. Nevertheless, metatranscriptomics informed about contrasting roles of bacteria during inflammation. Functions involved in nutrient transport, immune suppression and regulation of tissue damage were dramatically upregulated, perhaps contributed by homeostasis-promoting bacteria. Functions ostensibly increasing bacteria pathogenesis were also found upregulated, perhaps as a consequence of increased abundance of Proteobacteria. Bacterial protein synthesis appeared downregulated. In summary, shotgun metagenomics was useful to profile bacterial population composition and taxa relative abundance, but did not inform about differential gene content associated with inflammation. Metatranscriptomics was more robust for capturing bacterial metabolism in real time. Although both approaches are complementary, it is often not possible to apply them in parallel. We hope our data will help researchers to decide which approach is more appropriate for the study of different aspects of the microbiome.

Cation and Anion Channelrhodopsins: Sequence Motifs and Taxonomic Distribution.

Cation and anion channelrhodopsins (CCRs and ACRs, respectively) primarily from two algal species, Chlamydomonas reinhardtii and Guillardia theta, have become widely used as optogenetic tools to control cell membrane potential with light. We mined algal and other protist polynucleotide sequencing projects and metagenomic samples to identify 75 channelrhodopsin homologs from four channelrhodopsin families, including one revealed in dinoflagellates in this study. We carried out electrophysiological analysis of 33 natural channelrhodopsin variants from different phylogenetic lineages and 10 metagenomic homologs in search of sequence determinants of ion selectivity, photocurrent desensitization, and spectral tuning in channelrhodopsins. Our results show that association of a reduced number of glutamates near the conductance path with anion selectivity depends on a wider protein context, because prasinophyte homologs with a glutamate pattern identical to that in cryptophyte ACRs are cation selective. Desensitization is also broadly context dependent, as in one branch of stramenopile ACRs and their metagenomic homologs, its extent roughly correlates with phylogenetic relationship of their sequences. Regarding spectral tuning, we identified two prasinophyte CCRs with red-shifted spectra to 585 nm. They exhibit a third residue pattern in their retinal-binding pockets distinctly different from those of the only two types of red-shifted channelrhodopsins known (i.e., the CCR Chrimson and RubyACRs). In cryptophyte ACRs we identified three specific residue positions in the retinal-binding pocket that define the wavelength of their spectral maxima. Lastly, we found that dinoflagellate rhodopsins with a TCP motif in the third transmembrane helix and a metagenomic homolog exhibit channel activity. IMPORTANCE Channelrhodopsins are widely used in neuroscience and cardiology as research tools and are considered prospective therapeutics, but their natural diversity and mechanisms remain poorly characterized. Genomic and metagenomic sequencing projects are producing an ever-increasing wealth of data, whereas biophysical characterization of the encoded proteins lags behind. In this study, we used manual and automated patch clamp recording of representative members of four channelrhodopsin families, including a family in dinoflagellates that we report in this study. Our results contribute to a better understanding of molecular determinants of ionic selectivity, photocurrent desensitization, and spectral tuning in channelrhodopsins.

Pet dogs (Canis lupus familiaris) release their trapped and distressed owners: Individual variation and evidence of emotional contagion.

Domestic dogs have assisted humans for millennia. However, the extent to which these helpful behaviors are prosocially motivated remains unclear. To assess the propensity of pet dogs to actively rescue distressed humans without explicit training, this study tested whether sixty pet dogs would release their seemingly trapped owners from a large box. To examine the causal mechanisms that shaped this behavior, the readiness of each dog to open the box was tested in three conditions: 1) the owner sat in the box and called for help (distress test), 2) an experimenter placed high-value food rewards in the box (food test), and 3) the owner sat in the box and calmly read aloud (reading test). Dogs were as likely to release their distressed owner as to retrieve treats from inside the box, indicating that rescuing an owner may be a highly rewarding action for dogs. After accounting for opening ability, dogs released the owner more often when the owner called for help than when the owner read aloud calmly. In addition, opening latencies decreased with test number in the distress test but not the reading test. Thus, rescuing the owner could not be attributed solely to social facilitation, stimulus enhancement, or social contact-seeking behavior. Dogs displayed more stress behaviors in the distress test than in the reading test, and stress scores decreased with test number in the reading test but not in the distress test. This evidence of emotional contagion supports the hypothesis that rescuing the distressed owner was an empathetically-motivated prosocial behavior. Success in the food task and previous (in-home) experience opening objects were both strong predictors of releasing the owner. Thus, prosocial behavior tests for dogs should control for physical ability and previous experience.

Biofiltration of oil sands process water in fixed-bed biofilm reactors shapes microbial community structure for enhanced degradation of naphthenic acids.

Naphthenic acids (NAs) are a complex mixture of carboxylic acids present in oil sands process water (OSPW). Their recalcitrant nature makes them difficult to be removed from the environment using conventional remediation strategies. This study hypothesized that, upon continuous operation, biofiltration of OSPW in fixed-bed biofilm reactors would allow the development of NA-degrading microbial community within the biofilter following successful removal. Both raw and ozonated OSPW were treated in the biofilters and changes in microbial community were tested via 16S/18S amplicon sequencing and metatranscriptomics. Through switch from suspended growth to attached growth, a shift in indigenous microbial community was seen following by an increase in alpha diversity. Concomitantly, improved degradation of NAs was monitored, i.e., 35.8% and 69.4% of NAs were removed from raw and ozonated OSPW, respectively. Metatranscriptomics analysis suggested the presence of genes involved in the degradation of organic acids and petroleum-related compounds. Specifically, functional abundance of aromatic compounds' metabolism improved from 0.05% to 0.76%; whereas abundance of benzoate transport and degradation pathway increased from 0.04% to 0.64%. These changes conclude that continuous operation of OSPW in the bioreactors was in favor of shaping the overall microbiome towards better NA degradation.

Independent evolution of cutaneous lymphoma subclones in different microenvironments of the skin.

Mycosis fungoides (MF) is the most common cutaneous T-cell lymphoma. Lesions of MF are formed by hematogenous seeding the skin with polyclonal (clonotypically diverse) neoplastic T-cells which accumulate numerous mutations and display a high degree of mutational, intratumoral heterogeneity (ITH). A characteristic but poorly studied feature of MF is epidermotropism, the tendency to infiltrate skin epithelial layer (epidermis) in addition to the vascularized dermis. By sequencing the exomes of the microdissected clusters of lymphoma cells from the epidermis and the dermis, we found that those microenvironments comprised different malignant clonotypes. Subclonal structure witnessed the independent mutational evolution in the epidermis and dermis. Thus, the epidermal involvement in MF could not be explained by gradual infiltration from the dermis but was caused by a separate seeding process followed by a quasi-neutral, branched evolution. In conclusion, tissue microenvironments shape the subclonal architecture in MF leading to "ecological heterogeneity" which contributes to the total ITH. Since ITH adversely affects cancer prognosis, targeting the microenvironment may present therapeutic opportunities in MF and other cancers.

Branched evolution and genomic intratumor heterogeneity in the pathogenesis of cutaneous T-cell lymphoma.

Mycosis fungoides (MF) is a slowly progressive cutaneous T-cell lymphoma (CTCL) for which there is no cure. In the early plaque stage, the disease is indolent, but development of tumors heralds an increased risk of metastasis and death. Previous research into the genomic landscape of CTCL revealed a complex pattern of >50 driver mutations implicated in more than a dozen signaling pathways. However, the genomic mechanisms governing disease progression and treatment resistance remain unknown. Building on our previous discovery of the clonotypic heterogeneity of MF, we hypothesized that this lymphoma does not progress in a linear fashion as currently thought but comprises heterogeneous mutational subclones. We sequenced exomes of 49 cases of MF and identified 28 previously unreported putative driver genes. MF exhibited extensive intratumoral heterogeneity (ITH) of a median of 6 subclones showing a branched phylogenetic relationship pattern. Stage progression was correlated with an increase in ITH and redistribution of mutations from stem to clades. The pattern of clonal driver mutations was highly variable, with no consistent mutations among patients. Similar intratumoral heterogeneity was detected in leukemic CTCL (Sézary syndrome). Based on these findings, we propose a model of MF pathogenesis comprising divergent evolution of cancer subclones and discuss how ITH affects the efficacy of targeted drug therapies and immunotherapies for CTCL.

Clonotypic heterogeneity in cutaneous T-cell lymphoma (mycosis fungoides) revealed by comprehensive whole-exome sequencing.

Mycosis fungoides (MF), the most common type of cutaneous T-cell lymphoma, is believed to represent a clonal expansion of a transformed skin-resident memory T cell. T-cell receptor (TCR) clonality (ie, identical sequences of rearranged TCRα, TCRß, and TCRγ), the key premise of this hypothesis, has been difficult to document conclusively because malignant cells are not readily distinguishable from the tumor-infiltrating reactive lymphocytes that contribute to the TCR clonotypic repertoire of MF. Here, we have successfully adopted targeted whole-exome sequencing (WES) to identify the repertoire of rearranged TCR genes in tumor-enriched samples from patients with MF. Although some of the investigated MF biopsies had the expected frequency of monoclonal rearrangements of TCRγ corresponding to that of tumor cells, the majority of the samples presented multiple TCRγ, TCRα, and TCRß clonotypes by WES. Our findings are compatible with the model in which the initial malignant transformation in MF does not occur in mature memory T cells but rather at the level of T-lymphocyte progenitors before TCRß or TCRα rearrangements. We have also shown that WES can be combined with whole-transcriptome sequencing in the same sample, which enables comprehensive characterization of the TCR repertoire in relation to tumor content. WES/whole-transcriptome sequencing might be applicable to other types of T-cell lymphomas to determine clonal dominance and clonotypic heterogeneity in these malignancies.

Effective fecal microbiota transplantation for recurrent Clostridioides difficile infection in humans is associated with increased signalling in the bile acid-farnesoid X receptor-fibroblast growth factor pathway.

The mechanisms of efficacy for fecal microbiota transplantation (FMT) in treating recurrent Clostridioides difficile infection (rCDI) remain poorly defined, with restored gut microbiota-bile acid interactions representing one possible explanation. Furthermore, the potential implications for host physiology of these FMT-related changes in gut bile acid metabolism are also not well explored. In this study, we investigated the impact of FMT for rCDI upon signalling through the farnesoid X receptor (FXR)-fibroblast growth factor (FGF) pathway. Herein, we identify that in addition to restoration of gut microbiota and bile acid profiles, FMT for rCDI is accompanied by a significant, sustained increase in circulating levels of FGF19 and reduction in FGF21. These FGF changes were associated with weight gain post-FMT, to a level not exceeding the pre-rCDI baseline. Collectively, these data support the hypothesis that the restoration of gut microbial communities by FMT for rCDI is associated with an upregulated FXR-FGF pathway, and highlight the potential systemic effect of FMT.

A Survey of Molecular Heterogeneity in Hepatocellular Carcinoma.

Understanding the heterogeneity of dysregulated pathways associated with the development of hepatocellular carcinoma (HCC) may provide prognostic and therapeutic avenues for disease management. As HCC involves a complex process of genetic and epigenetic modifications, we evaluated expression of both polyadenylated transcripts and microRNAs from HCC and liver samples derived from two cohorts of patients undergoing either partial hepatic resection or liver transplantation. Copy number variants were inferred from whole genome low-pass sequencing data, and a set of 56 cancer-related genes were screened using an oncology panel assay. HCC was associated with marked transcriptional deregulation of hundreds of protein-coding genes. In the partially resected livers, diminished transcriptional activity was observed in genes associated with drug catabolism and increased expression in genes related to inflammatory responses and cell proliferation. Moreover, several long noncoding RNAs and microRNAs not previously linked with HCC were found to be deregulated. In liver transplant recipients, down-regulation of genes involved in energy production and up-regulation of genes associated with glycolysis were detected. Numerous copy number variants events were observed, with hotspots on chromosomes 1 and 17. Amplifications were more common than deletions and spanned regions containing genes potentially involved in tumorigenesis. Colony stimulating factor 1 receptor (CSF1R), fibroblast growth factor receptor 3 (FGFR3), fms-like tyrosine kinase 3 (FLT3), nucleolar phosphoprotein B23 (NPM1), platelet-derived growth factor receptor alpha polypeptide (PDGFRA), phosphatase and tensin homolog (PTEN), G-protein-coupled receptors-like receptor Smoothened (SMO), and tumor protein P53 (TP53) were mutated in all tumors; another 26 cancer-related genes were mutated with variable penetrance. Conclusion: Our results underscore the marked molecular heterogeneity between HCC tumors and reinforce the notion that precision medicine approaches are needed for management of individual HCC. These data will serve as a resource to generate hypotheses for further research to improve our understanding of HCC biology. (Hepatology Communications 2018; 00:000-000).

Novel mutations involving ßI-, ßIIA-, or ßIVB-tubulin isotypes with functional resemblance to ßIII-tubulin in breast cancer.

Tubulin is the target for very widely used anti-tumor drugs, including Vinca alkaloids, taxanes, and epothilones, which are an important component of chemotherapy in breast cancer and other malignancies. Paclitaxel and other tubulin-targeting drugs bind to the ß subunit of tubulin, which is a heterodimer of α and ß subunits. ß-Tubulin exists in the form of multiple isotypes, which are differentially expressed in normal and neoplastic cells and differ in their ability to bind to drugs. Among them, the ßIII isotype is overexpressed in many aggressive and metastatic cancers and may serve as a prognostic marker in certain types of cancer. The underpinning mechanisms accounting for the overexpression of this isotype in cancer cells are unclear. To better understand the role of ß-tubulin isotypes in cancer, we analyzed over 1000 clones from 90 breast cancer patients, sequencing their ß-tubulin isotypes, in search of novel mutations. We have elucidated two putative emerging molecular subgroups of invasive breast cancer, each of which involve mutations in the ßI-, ßIIA-, or ßIVB isotypes of tubulin that increase their structural, and possibly functional, resemblance to the ßIII isotype. A unifying feature of the first of the two subgroups is the mutation of the highly reactive C239 residue of ßI- or ßIVB-tubulin to L239, R239, Y239, or P239, culminating in probable conversion of these isotypes from ROS-sensitive to ROS-resistant species. In the second subgroup, ßI, ßIIA, and ßIVB have up to seven mutations to the corresponding residues in ßIII-tubulin. Given that ßIII-tubulin has emerged as a pro-survival factor, overexpression of this isotype may confer survival advantages to certain cancer cell types. In this mini-review, we bring attention to a novel mechanism by which cancer cells may undergo adaptive mutational changes involving alternate ß-tubulin isotypes to make them acquire some of the pro-survival properties of ßIII-tubulin. These "hybrid" tubulins, combining the sequences and/or properties of two wild-type tubulins (ßIII and either ßI, ßIIA, or ßIVB), are novel isotypes expressed solely in cancer cells and may contribute to the molecular understanding and stratification of invasive breast cancer and provide novel molecular targets for rational drug development.

Characterization of the Gut Microbiome Using 16S or Shotgun Metagenomics.

The advent of next generation sequencing (NGS) has enabled investigations of the gut microbiome with unprecedented resolution and throughput. This has stimulated the development of sophisticated bioinformatics tools to analyze the massive amounts of data generated. Researchers therefore need a clear understanding of the key concepts required for the design, execution and interpretation of NGS experiments on microbiomes. We conducted a literature review and used our own data to determine which approaches work best. The two main approaches for analyzing the microbiome, 16S ribosomal RNA (rRNA) gene amplicons and shotgun metagenomics, are illustrated with analyses of libraries designed to highlight their strengths and weaknesses. Several methods for taxonomic classification of bacterial sequences are discussed. We present simulations to assess the number of sequences that are required to perform reliable appraisals of bacterial community structure. To the extent that fluctuations in the diversity of gut bacterial populations correlate with health and disease, we emphasize various techniques for the analysis of bacterial communities within samples (α-diversity) and between samples (ß-diversity). Finally, we demonstrate techniques to infer the metabolic capabilities of a bacteria community from these 16S and shotgun data.

Cerebrospinal Fluid in a Small Cohort of Patients with Multiple Sclerosis Was Generally Free of Microbial DNA.

Multiple sclerosis (MS) is a common cause of non-traumatic neurologic disability with high incidence in many developed countries. Although the etiology of the disease remains elusive, it is thought to entail genetic and environmental causes, and microbial pathogens have also been envisioned as contributors to the phenotype. We conducted a metagenomic survey in cerebrospinal fluid (CSF) from 28 MS patients and 15 patients suffering other type of neurological conditions. We detected bacterial reads in eight out of the 15 non-MS patients and in a single MS patient, at an abundance >1% of total classified reads. Two patients were of special interest: one non-MS patient harbored ~73% bacterial reads, while an MS patient had ~83% bacterial reads. In the former case, Veillonella parvula, a bacterium occasionally found associated with meningitis was the predominant species, whilst Kocuria flava, apparently an environmental bacterium, predominated in the latter case. Thirty-four out of 43 samples contained <1% bacterial reads, which we regard as cross- or environmental contamination. A few viral reads corresponding to Epstein-Barr virus, cytomegalovirus, and parvovirus were also identified. Our results suggest that CSF of MS patients is often (but not always) free of microbial DNA.

Simulation and rubrics: technology and grading student performance in nurse anesthesia education.

The use of simulation technology has introduced a challenge for simulation nurse educators: evaluation of student performance. The subjectivity of student performance evaluation has been in need of improvement. It is imperative to provide clear and consistent information to the learner of expectations for their performance. Educators use objectives to define for the learner what the primary focus will be in the learning activities. Creation of rubrics to replace checklists to evaluate learner performance is a team task. Improved rubrics assist instructors in providing valuable, immediate, and postactivity feedback and consistency among instructors, and improved inter-rater reliability.

Fecal Microbial Transplant After Ileocolic Resection Reduces Ileitis but Restores Colitis in IL-10-/- Mice.

BACKGROUND: Ileocolic resection (ICR) is frequently performed for Crohn's disease; however, disease commonly recurs early in the neoterminal ileum. The aim of this study was to use the IL-10(-/-) mouse to determine the effects of ICR on gut microbiome and immune function and if postoperative fecal microbial transplant (FMT) would improve disease. METHODS: ICR was performed in 129S1/SvlmJ IL10(-/-) mice followed by FMT using stool from wild-type mice. Sham-transplant mice received their own stool. Stool samples were collected on day 0, day 13 (after ICR), and day 27 (after FMT) for whole metagenome shot-gun sequencing. Mucosal-associated bacteria were quantified with quantitative PCR and visualized by fluorescent in situ hybridization. Tissue cytokines were measured with multiplex arrays and mononuclear phagocyte populations by flow cytometry. RESULTS: Surgery induced microbial functional and taxonomic shifts, decreased diversity, and depleted Bacteroidia and Clostridia. ICR mice had reduced colitis but worse ileitis with bacterial overgrowth, increased translocation, and reduction in tissue macrophages. FMT prevented ileitis but restored colitis and allowed for a bloom of γ-proteobacteria. In the colon, ICR and sham transplant were associated with recruitment of tolerogenic dendritic cells, whereas FMT shifted these immune cell subsets to control profiles along with increasing cytokine levels. CONCLUSIONS: This study suggests that surgical-induced immune dysfunction and microbial dysbiosis with impaired clearance may be the underlying cause of the early ulcerations found in the ileum of patients with Crohn's disease after ICR. FMT has an immunostimulatory effect on the postoperative intestine, which was beneficial in preventing ileitis, but detrimental in restoring colonic injury after surgery.