The gut bacterium and pathobiont Bacteroides vulgatus activates NF-κB in a human gut epithelial cell line in a strain and growth phase dependent manner

The gut microbiota is increasingly implicated in the pathogenesis of Crohn's disease (CD) and ulcerative colitis (UC) although the identity of the bacteria that underpin these diseases has remained elusive. The pathobiont Bacteroides vulgatus has been associated with both diseases although relatively little is known about how its growth and functional activity might drive the host inflammatory response. We identified an ATP Binding Cassette (ABC) export system and lipoprotein in B. vulgatus ATCC 8482 and B. vulgatus PC510 that displayed significant sequence similarity to an NF-κB immunomodulatory regulon previously identified on a CD-derived metagenomic fosmid clone. Interestingly, the ABC export system was specifically enriched in CD subjects suggesting that it may be important for colonization and persistence in the CD gut environment. Both B. vulgatus ATCC 8482 and PC510 activated NF-κB in a strain and growth phase specific manner in a HT-29/kb-seap-25 enterocyte like cell line. B. vulgatus ATCC 8482 also activated NF-κB in a Caco-2-NF-κBluc enterocyte like and an LS174T-NF-κBluc goblet cell like cell lines, and induced NF-κB-p65 subunit nuclear translocation and IL-6, IL-8, CXCL-10 and MCP-1 gene expression. Despite this, NF-κB activation was not coincident with maximal expression of the ABC exporter or lipoprotein in B. vulgatus PC510 suggesting that the regulon may be necessary but not sufficient for the immunomodulatory effects

Imaging practice in low-grade gliomas among European specialized centers and proposal for a minimum core of imaging

Objective: Imaging studies in diffuse low-grade gliomas (DLGG) vary across centers. In order to establish a minimal core of imaging necessary for further investigations and clinical trials in the field of DLGG, we aimed to establish the status quo within specialized European centers. Methods: An online survey composed of 46 items was sent out to members of the European Low-Grade Glioma Network, the European Association of Neurosurgical Societies, the German Society of Neurosurgery and the Austrian Society of Neurosurgery. Results: A total of 128 fully completed surveys were received and analyzed. Most centers (n=96, 75%) were academic and half of the centers (n=64, 50%) adhered to a dedicated treatment program for DLGG. There were national differences regarding the sequences enclosed in MRI imaging and use of PET, however most included T1 (without and with contrast, 100%), T2 (100%) and TIRM or FLAIR (20, 98%). DWI is performed by 80% of centers and 61% of centers regularly performed PWI.ConclusionA minimal core of imaging composed of T1 (w/wo contrast), T2, TIRM/FLAIR, PWI and DWI could be identified. All morphologic images should be obtained in a slice thickness of 3mm. No common standard could be obtained regarding advanced MRI protocols and PET. Importance of the study: We believe that our study makes a significant contribution to the literature because we were able to determine similarities in numerous aspects of LGG imaging. Using the proposed minimal core of imaging in clinical routine will facilitate future cooperative studies

Increased Gut Permeability and Microbiota Change Associate with Mesenteric Fat Inflammation and Metabolic Dysfunction in Diet-Induced Obese Mice

We investigated the relationship between gut health, visceral fat dysfunction and metabolic disorders in diet-induced obesity. C57BL/6J mice were fed control or high saturated fat diet (HFD). Circulating glucose, insulin and inflammatory markers were measured. Proximal colon barrier function was assessed by measuring transepithelial resistance and mRNA expression of tight-junction proteins. Gut microbiota profile was determined by 16S rDNA pyrosequencing. Tumor necrosis factor (TNF)-α and interleukin (IL)-6 mRNA levels were measured in proximal colon, adipose tissue and liver using RT-qPCR. Adipose macrophage infiltration (F4/80+) was assessed using immunohistochemical staining. HFD mice had a higher insulin/glucose ratio (P = 0.020) and serum levels of serum amyloid A3 (131%; P = 0.008) but reduced circulating adiponectin (64%; P = 0.011). In proximal colon of HFD mice compared to mice fed the control diet, transepithelial resistance and mRNA expression of zona occludens 1 were reduced by 38% (P<0.001) and 40% (P = 0.025) respectively and TNF-α mRNA level was 6.6-fold higher (P = 0.037). HFD reduced Lactobacillus (75%; P<0.001) but increased Oscillibacter (279%; P = 0.004) in fecal microbiota. Correlations were found between abundances of Lactobacillus (r = 0.52; P = 0.013) and Oscillibacter (r = −0.55; P = 0.007) with transepithelial resistance of the proximal colon. HFD increased macrophage infiltration (58%; P = 0.020), TNF-α (2.5-fold, P<0.001) and IL-6 mRNA levels (2.5-fold; P = 0.008) in mesenteric fat. Increased macrophage infiltration in epididymal fat was also observed with HFD feeding (71%; P = 0.006) but neither TNF-α nor IL-6 was altered. Perirenal and subcutaneous adipose tissue showed no signs of inflammation in HFD mice. The current results implicate gut dysfunction, and attendant inflammation of contiguous adipose, as salient features of the metabolic dysregulation of diet-induced obesity

Intestinal microbiota in human health and disease: the impact of probiotics

The complex communities of microorganisms that colonise the human gastrointestinal tract play an important role in human health. The development of culture-independent molecular techniques has provided new insights in the composition and diversity of the intestinal microbiota. Here, we summarise the present state of the art on the intestinal microbiota with specific attention for the application of high-throughput functional microbiomic approaches to determine the contribution of the intestinal microbiota to human health. Moreover, we review the association between dysbiosis of the microbiota and both intestinal and extra-intestinal diseases. Finally, we discuss the potential of probiotic microorganism to modulate the intestinal microbiota and thereby contribute to health and well-being. The effects of probiotic consumption on the intestinal microbiota are addressed, as well as the development of tailor-made probiotics designed for specific aberrations that are associated with microbial dysbiosis

Imaging practice in low-grade gliomas among European specialized centers and proposal for a minimum core of imaging.

OBJECTIVE: Imaging studies in diffuse low-grade gliomas (DLGG) vary across centers. In order to establish a minimal core of imaging necessary for further investigations and clinical trials in the field of DLGG, we aimed to establish the status quo within specialized European centers. METHODS: An online survey composed of 46 items was sent out to members of the European Low-Grade Glioma Network, the European Association of Neurosurgical Societies, the German Society of Neurosurgery and the Austrian Society of Neurosurgery. RESULTS: A total of 128 fully completed surveys were received and analyzed. Most centers (n = 96, 75%) were academic and half of the centers (n = 64, 50%) adhered to a dedicated treatment program for DLGG. There were national differences regarding the sequences enclosed in MRI imaging and use of PET, however most included T1 (without and with contrast, 100%), T2 (100%) and TIRM or FLAIR (20, 98%). DWI is performed by 80% of centers and 61% of centers regularly performed PWI. CONCLUSION: A minimal core of imaging composed of T1 (w/wo contrast), T2, TIRM/FLAIR, PWI and DWI could be identified. All morphologic images should be obtained in a slice thickness of ≤ 3 mm. No common standard could be obtained regarding advanced MRI protocols and PET. IMPORTANCE OF THE STUDY: We believe that our study makes a significant contribution to the literature because we were able to determine similarities in numerous aspects of LGG imaging. Using the proposed "minimal core of imaging" in clinical routine will facilitate future cooperative studies

Calculational and experimental investigations of void effect - A simple theoretical model for space-dependent leakage treatment of heterogeneous assemblies

This method, which takes into account the influence of assembly heterogeneity on neutron leakage, is based on the heterogeneous B1 formalism, which assumes the existence of a fundamental mode in an infinite and regular lattice of heterogeneous assemblies A simplified formalism, TIBERE, is presented that allows one to define directional space-dependent leakage coefficients This method, introduced for two-dimensional x-y geometry in the APOLLO-2 multigroup transport code, uses classical and directional first-flight collision probabilities One can now define leakage cross sections as additional absorption cross sections that have space and energy dependence, as well as all other cross sections Hence, one obtains perfectly consistent reaction and leakage rates used in an equivalence procedure, determining cell-homogenized parameters for a whole core calculation The study of this refined heterogeneous leakage treatment was undertaken because of the insufficiency of the homogeneous leakage model, especially in cases when an assembly contain voided zones or almost voided zones, ie, zones with a long mean free path, so that the streaming effect may become important The fission rate comparison between the EPICURE reactor experimental results and the results of the corresponding whole reactor calculations were accomplished, with leakages calculated by the homogeneous and the TIBERE procedures of the APOLLO-2 cod

ÉTUDE EXPÉRIMENTALE DU RALENTISSEMENT DANS LES GAZ DE L'ÉJECTION DE MATIÈRE INDUITE PAR CHOC

Nous décrivons une méthode expérimentale utilisant simultanément la radiographie X-éclair et la caméra ultra-rapide à image intégrale en ombroscopie dans le but d'étudier le ralentissement de l'éjection de matière induite par choc dans un gaz dense situé en avant de la surface libre. Les expériences ont été réalisées avec de l'étain choqué à 40 GPa par un générateur explosif d'onde plane ou à 16 GPa avec un générateur explosif à relèvement latéral et à différents gaz (argon, azote, hélium) à différentes pressions initiales (de 0 à 0,8 MPa). Avec l'argon, nous notons un ralentissement important des particules éjectées et quelquefois un arrêt (quelques microsecondes après le débouché du choc dans le gaz), qui dépend directement de la pression initiale de l'argon. L'azote, entraîne un ralentissement moins important que l'argon et l'hélium, n'a aucune influence sur le déplacement des particules éjectées.We describe an experimental technique using both flash X-Ray radiography and ultra-high speed framing camera shadowgraphy in order to study the slowing down of shock-induced matter ejection appearing when a dense gaz is put ahead the sample free surface. Experiments have been achieved with tin shocked at 40 GPa by an explosive plane wave generator or at 16 GPa by an explosive lateral wave generator and different gas (argon, nitrogen, helium) at different initial pressures (from 0 to 0.8 MPa). With argon gas, we show up a drastic slowing down of the ejected particles and, sometimes, a quick stopping (a few microseconds after shock bursts into the gas), which directly depends on the argon initial pressure. Nitrogen induces a slowing down less strong than argon, and helium has no influence on the ejected particle motion

MESURE DE LA TEMPÉRATURE RÉSIDUELLE DES MATÉRIAUX SOUMIS À UN CHOC INTENSE

We describe an experimental measurement technique which permits to evaluate the free surface temperature of a shock loaded metallic sample. The radiative infrared emission is carried over from the firing chamber to the pyrometer by a fluoride glass fiber. The pyrometer and the measurement technique are described. The free surface temperature of a shock loaded polished aluminum sample is measured and discussed