Characterization of the Core and Caste-Specific Microbiota in the Termite, Reticulitermes flavipes

The hindgut of the termite Reticulitermes flavipes harbors a complex symbiotic community consisting of protists, bacteria, and archaea. These symbionts aid in the digestion of lignocellulose from the termite’s wood meal. Termite hindguts were sampled and the V4 hyper-variable region of the 16S rRNA gene was sequenced and analyzed from individual termites. The core microbiota of worker termites consisted of 69 OTUs at the 97% identity level, grouped into 16 taxa, and together accounted for 67.05% of the sequences from the bacterial community. The core was dominated by Treponema, which contained 36 different OTUs and accounted for ~32% of the sequences, which suggests Treponema spp have an important impact on the overall physiology in the hindgut. Bray-Curtis beta diversity metrics showed that hindgut samples from termites of the same colony were more similar to each other than to samples from other colonies despite possessing a core that accounted for the majority of the sequences. The specific tasks and dietary differences of the termite castes could have an effect on the composition of the microbial community. The hindgut microbiota of termites from the alate castes differed from the worker caste with significantly lower abundances of Treponema and Endomicrobia, which dominated the hindgut microbiota in workers and soldiers. Protist abundances were also quantified in the same samples using qPCR of the 18S rRNA gene. Parabasalia abundances dropped significantly in the winged alates and the Oxymonadida abundances dropped in both alate castes. These data suggest that the changes in diet or overall host physiology affected the protist and bacterial populations in the hindgut. The in-depth bacterial characterization and protist quantification in this study sheds light on the potential community dynamics within the R. flavipes hindgut and identified a large and complex core microbiota in termites obtained from multiple colonies and castes

Early benefit assessment (EBA) in Germany: analysing decisions 18 months after introducing the new AMNOG legislation

Since the introduction of the German health care reform in January 2011, an early benefit assessment (EBA) is required for all new medicines. Pharmaceutical manufacturers have to submit a benefit dossier for evaluation by the Institute for Quality and Efficiency in Health Care (IQWiG). A final decision is made by the Federal Joint Committee (G-BA). The aim of this investigation was to analyse the outcomes 18 months after introduction of the new legislation and to identify critical areas requiring further discussion and development. All EBAs commenced prior to June 2012 were included. The G-BA website was used to obtain manufacturers' benefit dossiers, IQWiG assessments, and G-BA decisions. Four areas of interest were analysed: levels of additional benefit, appropriate comparative therapy (ACT), patient-relevant endpoints, and adverse events. Twenty-seven EBAs were analysed. IQWiG stated a benefit in 50 % of EBAs, whereas G-BA stated a benefit in 63 %, but only in 50 % of identified subgroups and 40 % of patients involved. In 12 EBAs, the ACT suggested by G-BA differed from the comparator used in phase III trials. The G-BA reported no benefits on health-related quality of life. Discrepancies arose in morbidity outcomes such as 'progression-free survival' and 'sustained virological response'. Categorisation and balancing of adverse events was conducted within various assessments. Considerable variance was observed in the levels of additional benefit reported by pharmaceutical manufacturers, IQWiG and G-BA. The areas of disagreement included ACT selection, definition of subgroups and patient-relevant endpoints, and classification and balancing of adverse events.Roche Pharma A

Identification and X-ray Co-crystal Structure of a Small-Molecule Activator of LFA-1-ICAM-1 Binding

The integrin Leucocyte function associated antigen 1 (LFA-1) is a heterodimeric immune receptor ubiquitously expressed on all leucocytes. Its interaction with Intercellular adhesion molecule 1 (ICAM-1) provides a critical recognition event between T-cells and antigen presenting cells in the immune systems efforts to pull off an early stage cell mediated immune response.[1–3] The LFA-1/ICAM-1 axis has thus been explored as a target interaction for drug discovery.[4–7] Furthermore, the structural changes of LFA-1 upon activation and interaction with ICAM-1 also make the LFA-1/ICAM-1 interaction an interesting example of protein-protein interaction (PPI) inhibition by small molecule inhibitors.[8,9] While protein-protein interaction inhibition by small molecules is considered to be the ultimate art in drug design, even fewer examples of true agonists of PPIs have been reported.[10–12] As for LFA-1, such activators would have interesting applications in rare hereditary genetic disorders called Leucocyte adhesion deficiency (LAD) or as potential enhancers of tumour immunotherapy.[13,14] Although, one such activator has been described recently, closer biological investigation has shown that it ultimately worked as an inhibitor on a cellular level by locking the LFA-1/ICAM-1 interaction when reversibility was needed for detachment of immune cells from endothelial surfaces and tissue infiltration.[15] Herein we describe the identification and structural biology of IBE-667, an ICAM-1 binding enhancer for LFA-1 from on-bead screening of tagged one-bead one-compound combinatorial libraries by confocal nanoscanning and bead picking (CONA).[16] Cellular assays demonstrate the activity of IBE-667 in promoting the binding of LFA-1 on activated immune cells to ICAM-1. X-ray structure based analysis did not only allow us to explain the molecular features of IBE-667 binding to LFA-1 but also offers an explanation for its mode of action

Complex Evolutionary History of the Aeromonas veronii Group Revealed by Host Interaction and DNA Sequence Data

Aeromonas veronii biovar sobria, Aeromonas veronii biovar veronii, and Aeromonas allosaccharophila are a closely related group of organisms, the Aeromonas veronii Group, that inhabit a wide range of host animals as a symbiont or pathogen. In this study, the ability of various strains to colonize the medicinal leech as a model for beneficial symbiosis and to kill wax worm larvae as a model for virulence was determined. Isolates cultured from the leech out-competed other strains in the leech model, while most strains were virulent in the wax worms. Three housekeeping genes, recA, dnaJ and gyrB, the gene encoding chitinase, chiA, and four loci associated with the type three secretion system, ascV, ascFG, aexT, and aexU were sequenced. The phylogenetic reconstruction failed to produce one consensus tree that was compatible with most of the individual genes. The Approximately Unbiased test and the Genetic Algorithm for Recombination Detection both provided further support for differing evolutionary histories among this group of genes. Two contrasting tests detected recombination within aexU, ascFG, ascV, dnaJ, and gyrB but not in aexT or chiA. Quartet decomposition analysis indicated a complex recent evolutionary history for these strains with a high frequency of horizontal gene transfer between several but not among all strains. In this study we demonstrate that at least for some strains, horizontal gene transfer occurs at a sufficient frequency to blur the signal from vertically inherited genes, despite strains being adapted to distinct niches. Simply increasing the number of genes included in the analysis is unlikely to overcome this challenge in organisms that occupy multiple niches and can exchange DNA between strains specialized to different niches. Instead, the detection of genes critical in the adaptation to specific niches may help to reveal the physiological specialization of these strains

Progressive skin fibrosis is associated with a decline in lung function and worse survival in patients with diffuse cutaneous systemic sclerosis in the European Scleroderma Trials and Research (EUSTAR) cohort.

Objectives To determine whether progressive skin fibrosis is associated with visceral organ progression and mortality during follow-up in patients with diffuse cutaneous systemic sclerosis (dcSSc). Methods We evaluated patients from the European Scleroderma Trials and Research database with dcSSc, baseline modified Rodnan skin score (mRSS) ≥7, valid mRSS at 12±3 months after baseline and ≥1 annual follow-up visit. Progressive skin fibrosis was defined as an increase in mRSS >5 and ≥25% from baseline to 12±3 months. Outcomes were pulmonary, cardiovascular and renal progression, and all-cause death. Associations between skin progression and outcomes were evaluated by Kaplan-Meier survival analysis and multivariable Cox regression. Results Of 1021 included patients, 78 (7.6%) had progressive skin fibrosis (skin progressors). Median follow-up was 3.4 years. Survival analyses indicated that skin progressors had a significantly higher probability of FVC decline ≥10% (53.6% vs 34.4%; p<0.001) and all-cause death (15.4% vs 7.3%; p=0.003) than non-progressors. These significant associations were also found in subgroup analyses of patients with either low baseline mRSS (≤22/51) or short disease duration (≤15 months). In multivariable analyses, skin progression within 1 year was independently associated with FVC decline ≥10% (HR 1.79, 95% CI 1.20 to 2.65) and all-cause death (HR 2.58, 95% CI 1.31 to 5.09). Conclusions Progressive skin fibrosis within 1 year is associated with decline in lung function and worse survival in dcSSc during follow-up. These results confirm mRSS as a surrogate marker in dcSSc, which will be helpful for cohort enrichment in future trials and risk stratification in clinical practice

Relationship between the Clinical Frailty Scale and short-term mortality in patients ≥ 80 years old acutely admitted to the ICU: a prospective cohort study.

BACKGROUND: The Clinical Frailty Scale (CFS) is frequently used to measure frailty in critically ill adults. There is wide variation in the approach to analysing the relationship between the CFS score and mortality after admission to the ICU. This study aimed to evaluate the influence of modelling approach on the association between the CFS score and short-term mortality and quantify the prognostic value of frailty in this context. METHODS: We analysed data from two multicentre prospective cohort studies which enrolled intensive care unit patients ≥ 80 years old in 26 countries. The primary outcome was mortality within 30-days from admission to the ICU. Logistic regression models for both ICU and 30-day mortality included the CFS score as either a categorical, continuous or dichotomous variable and were adjusted for patient's age, sex, reason for admission to the ICU, and admission Sequential Organ Failure Assessment score. RESULTS: The median age in the sample of 7487 consecutive patients was 84 years (IQR 81-87). The highest fraction of new prognostic information from frailty in the context of 30-day mortality was observed when the CFS score was treated as either a categorical variable using all original levels of frailty or a nonlinear continuous variable and was equal to 9% using these modelling approaches (p < 0.001). The relationship between the CFS score and mortality was nonlinear (p < 0.01). CONCLUSION: Knowledge about a patient's frailty status adds a substantial amount of new prognostic information at the moment of admission to the ICU. Arbitrary simplification of the CFS score into fewer groups than originally intended leads to a loss of information and should be avoided. Trial registration NCT03134807 (VIP1), NCT03370692 (VIP2)