Meeting update: faecal microbiota transplantation––bench, bedside, courtroom?

A group of stakeholders met, under the aegis of the British Society of Gastroenterology, to discuss the current landscape of faecal microbiota transplant- ation (FMT) within the UK and beyond. The meeting covered a wide range of topics, ranging from the practical aspects of establishing an FMT service and regu- latory issues relating to its delivery, to research implications and likely future directions

Star-forming galaxies versus low- and high-excitation radio AGN in the VLA-COSMOS 3GHz Large Project

We study the composition of the faint radio population selected from the VLA-COSMOS 3GHz Large Project, a radio continuum survey performed at 10 cm wavelength. The survey covers the full 2 square degree COSMOS field with mean $rms\sim2.3$ $\mu$Jy/beam, cataloging 10,899 source components above $5\times rms$. By combining these radio data with UltraVISTA, optical, near-infrared, and Spitzer/IRAC mid-infrared data, as well as X-ray data from the Chandra Legacy, and Chandra COSMOS surveys, we gain insight into the emission mechanisms within our radio sources out to redshifts of $z\sim5$. From these emission characteristics we classify our souces as star forming galaxies or AGN. Using their multi-wavelength properties we further separate the AGN into sub-samples dominated by radiatively efficient and inefficient AGN, often referred to as high- and low-excitation emission line AGN. We compare our method with other results based on fitting of the sources' spectral energy distributions using both galaxy and AGN spectral models, and those based on the infrared-radio correlation. We study the fractional contributions of these sub-populations down to radio flux levels of $\sim$10 $\mu$Jy. We find that at 3 GHz flux densities above $\sim$400 $\mu$Jy quiescent, red galaxies, consistent with the low-excitation radio AGN class constitute the dominant fraction. Below densities of $\sim$200 $\mu$Jy star-forming galaxies begin to constitute the largest fraction, followed by the low-excitation, and X-ray- and IR-identified high-excitation radio AGN.Comment: 7 pages, 3 figures, The many facets of extragalactic radio surveys: towards new scientific challenges, Bologna 20-23 October 201

Hepatobiliary surgeons meet immunologists : the case of colorectal liver metastases patients

The burgeoning field of cancer immunology demands a change in the paradigm of cancer patient management. The understanding of the course of a given malignant disease should also include the host immune system as one of the key factors in determining the patient's prognosis. Surgical and medical oncologists need to understand the basic and advanced applications of immunotherapies, which are rapidly evolving, and are nowadays an integral part of the armamentarium for the treatment of cancer patients. In the present work, we review the current knowledge concerning the immune landscape of colorectal cancer (CRC) patients with liver metastases, as recently discovered

The prevalence and predictors of comorbid bipolar disorder and obsessive-compulsive disorder: A systematic review and meta-analysis

Abstract Background: Although some authors have recently investigated the co-occurrence of anxiety and bipolar disorders, the topic remains insufficiently studied. Defining the prevalence and predictors of BD-OCD comorbidity has important nosological, clinical and therapeutic implications. Methods: A systematic review and meta-analysis was conducted on the prevalence and predictors of comorbid BD-OCD. Relevant papers published through March 30th, 2015 were identified searching the electronic databases MEDLINE, Embase, PsycINFO and the Cochrane Library. Results: 46 articles met inclusion criteria. The pooled prevalence of OCD in BD was 17.0% (95% CI 12.7-22.4%), which was comparable to the results reported by the pooled prevalence of BD in OCD (18.35%, 95% CI 13.2-24.8%). With regard to OCD-BD predictors, a higher mean age predicted a lower prevalence of OCD in BD patients. Sub group meta-analyses reported higher OCD prevalence rates in BD children and adolescents (24.2%, compared to 13.5% in adults), in BD-I patients (24.6%, compared to 13.6% in mixed BD patients), and among population-based studies (22.2%, compared to 13.2% in hospital-based studies). Limitations: Most studies use retrospective assessment scales with low sensitivity in discriminating true ego-dystonic obsessions from depressive ruminations that may bias results towards an overestimation of obsessive symptom prevalence. Conclusions: This first systematic review and meta-analysis of the prevalence and predictors of comorbid BD-OCD confirms that BD-OCD comorbidity is a common condition in psychiatry with children and adolescents and BD-I patients as the most affected subgroups

Dissimilarity of the gut-lung axis and dysbiosis of the lower airways in ventilated preterm infants.

BACKGROUND: Chronic lung disease of prematurity (CLD), also called bronchopulmonary dysplasia, is a major consequence of preterm birth but the role of the microbiome in its development remains unclear. We, therefore, assessed the progression of the bacterial community in ventilated preterm infants over time in the upper and lower airways, and assessed the gut-lung axis by comparing the upper and lower airways bacterial communities with the stool findings. Finally, we assessed if the bacterial communities were associated with lung inflammation to suggest dysbiosis. METHODS: We serially sampled multiple anatomical sites including the upper airway (nasopharyngeal aspirates, NPA), lower airways (tracheal aspirate fluid, TAF, and bronchoalveolar lavage fluid, BAL) and the gut (stool) of ventilated preterm-born infants. Bacterial DNA load was measured in all samples and sequenced using the V3-V4 region of the 16S rRNA gene RESULTS: From 1102 (539 NPA, 276 TAF, 89 BAL, 198 stool) samples from 55 preterm infants, 352 (32%) amplified suitably for 16 s RNA gene sequencing. Bacterial load was low at birth, quickly increased with time but was associated with predominant operational taxonomic units (OTUs) in all sample types. There was dissimilarity in bacterial communities between the upper and lower airways and the gut with a separate dysbiotic inflammatory process occurring in the lower airways of infants. Individual OTUs were associated with increased inflammatory markers. CONCLUSIONS: Taken together, these findings suggest that targeted treatment of the predominant organisms, including those not routinely treated such as Ureaplasma spp., may decrease the development of CLD in preterm-born infants

Bilevel programming methods for computing single-leader-multi-follower equilibria in normal-form and polymatrix games

The concept of leader-follower (or Stackelberg) equilibrium plays a central role in a number of real-world applications bordering on mathematical optimization and game theory. While the single-follower case has been investigated since the inception of bilevel programming with the seminal work of von Stackelberg, results for the case with multiple followers are only sporadic and not many computationally affordable methods are available. In this work, we consider Stackelberg games with two or more followers who play a (pure or mixed) Nash equilibrium once the leader has committed to a (pure or mixed) strategy, focusing on normal-form and polymatrix games. As customary in bilevel programming, we address the two extreme cases where, if the leader\u2019s commitment originates more Nash equilibria in the followers\u2019 game, one which either maximizes (optimistic case) or minimizes (pessimistic case) the leader\u2019s utility is selected. First, we show that, in both cases and when assuming mixed strategies, the optimization problem associated with the search problem of finding a Stackelberg equilibrium is NP-hard and not in Poly-APX unless P= NP. We then consider different situations based on whether the leader or the followers can play mixed strategies or are restricted to pure strategies only, proposing exact nonconvex mathematical programming formulations for the optimistic case for normal-form and polymatrix games. For the pessimistic problem, which cannot be tackled with a (single-level) mathematical programming formulation, we propose a heuristic black-box algorithm. All the methods and formulations that we propose are thoroughly evaluated computationally

The properties of the AGN torus as revealed from a set of unbiased NuSTAR observations

The obscuration observed in active galactic nuclei (AGN) is mainly caused by dust and gas distributed in a torus-like structure surrounding the supermassive black hole (SMBH). However, properties of the obscuring torus of the AGN in X-ray have not been fully investigated yet due to the lack of high-quality data and proper models. In this work, we perform a broadband X-ray spectral analysis of a large, unbiased sample of obscured AGN (with line-of-sight column density 23$\le$log(NH)$\le$24) in the nearby universe which has high-quality archival NuSTAR data. The source spectra are analyzed using the recently developed borus02 model, which enables us to accurately characterize the physical and geometrical properties of AGN obscuring tori. We also compare our results obtained from the unbiased Compton thin AGN with those of Compton-thick AGN. We find that Compton thin and Compton-thick AGN may possess similar tori, whose average column density is Compton thick (N$\rm _{H,tor,ave}$ $\sim$1.4$\times$10$^{24}$ cm$^{-2}$), but they are observed through different (under-dense or over-dense) regions of the tori. We also find that the obscuring torus medium is significantly inhomogeneous, with the torus average column densities significantly different from their line-of-sight column densities (for most of the sources in the sample). The average torus covering factor of sources in our unbiased sample is c$_f$=0.67, suggesting that the fraction of unobscured AGN is $\sim$33%. We develop a new method to measure the intrinsic line-of-sight column density distribution of AGN in the nearby universe, which we find the result is in good agreement with the constraints from recent population synthesis models.Comment: 16 pages, 14 figures, 7 tables; accepted by A&

Ethnicity associated microbial and metabonomic profiling in newly diagnosed ulcerative colitis

Introduction: Ulcerative colitis (UC) differs across geography and ethnic groups. Gut microbial diversity plays a pivotal role in disease pathogenesis and differs across ethnic groups. The functional diversity in microbial-driven metabolites may have a pathophysiologic role and offer new therapeutic avenues. Methods: Demographics and clinical data were recorded from newly diagnosed UC patients. Blood, urine and faecal samples were collected at three time points over one year. Bacterial content was analysed by 16S rRNA sequencing. Bile acid profiles and polar molecules in three biofluids were measured using liquid-chromatography mass spectrometry (HILIC) and nuclear magnetic resonance spectroscopy. Results: We studied 42 patients with a new diagnosis of UC (27 South Asians; 15 Caucasians) with 261 biosamples. There were significant differences in relative abundance of bacteria at the phylum, genus and species level. Relative concentrations of urinary metabolites in South Asians were significantly lower for hippurate (positive correlation for Ruminococcus) and 4-cresol sulfate (Clostridia) (p<0.001) with higher concentrations of lactate (negative correlation for Bifidobacteriaceae). Faecal conjugated and primary conjugated bile acids concentrations were significantly higher in South Asians (p=0.02 and p=0.03 respectively). Results were unaffected by diet, phenotype, disease severity and ongoing therapy. Comparison of time points at diagnosis and at 1 year did not reveal changes in microbial and metabolic profile. Conclusion: Ethnic-related microbial metabolite associations were observed in South Asians with UC. This suggests a predisposition to UC may be influenced by environmental factors reflected in a distinct gene-environment interaction. The variations may serve as markers to identify risk factors for UC and modified to enhance therapeutic response

Resolving the cosmic X-ray background with a next-generation high-energy X-ray observatory

The cosmic X-ray background (CXB), which peaks at an energy of ~30 keV, is produced primarily by emission from accreting supermassive black holes (SMBHs). The CXB therefore serves as a constraint on the integrated SMBH growth in the Universe and the accretion physics and obscuration in active galactic nuclei (AGNs). This paper gives an overview of recent progress in understanding the high-energy (>~10 keV) X-ray emission from AGNs and the synthesis of the CXB, with an emphasis on results from NASA's NuSTAR hard X-ray mission. We then discuss remaining challenges and open questions regarding the nature of AGN obscuration and AGN physics. Finally, we highlight the exciting opportunities for a next-generation, high-resolution hard X-ray mission to achieve the long-standing goal of resolving and characterizing the vast majority of the accreting SMBHs that produce the CXB.Comment: Science White paper submitted to Astro2020 Decadal Survey; 5 pages, 3 figures, plus references and cover pag