Constitutive TL1A (TNFSF15) Expression on Lymphoid or Myeloid Cells Leads to Mild Intestinal Inflammation and Fibrosis

TL1A is a member of the TNF superfamily and its expression is increased in the mucosa of inflammatory bowel disease patients. Moreover, a subset of Crohn's disease (CD) patients with the risk TL1A haplotype is associated with elevated TL1A expression and a more severe disease course. To investigate the in vivo role of elevated TL1A expression, we generated two transgenic (Tg) murine models with constitutive Tl1a expression in either lymphoid or myeloid cells. Compared to wildtype (WT) mice, constitutive expression of Tl1a in either lymphoid or myeloid cells showed mild patchy inflammation in the small intestine, which was more prominent in the ileum. In addition, mice with constitutive Tl1a expression exhibited enhanced intestinal and colonic fibrosis compared to WT littermates. The percentage of T cells expressing the gut homing chemokine receptors CCR9 and CCR10 was higher in the Tl1a Tg mice compared to WT littermates. Sustained expression of Tl1A in T cells also lead to increased Foxp3+ Treg cells. T cells or antigen presenting cells (APC) with constitutive expression of Tl1a were found to have a more activated phenotype and mucosal mononuclear cells exhibit enhanced Th1 cytokine activity. These results indicated an important role of TL1A in mucosal T cells and APC function and showed that up-regulation of TL1A expression can promote mucosal inflammation and gut fibrosis

X-ray Absorption and Reflection in Active Galactic Nuclei

X-ray spectroscopy offers an opportunity to study the complex mixture of emitting and absorbing components in the circumnuclear regions of active galactic nuclei, and to learn about the accretion process that fuels AGN and the feedback of material to their host galaxies. We describe the spectral signatures that may be studied and review the X-ray spectra and spectral variability of active galaxies, concentrating on progress from recent Chandra, XMM-Newton and Suzaku data for local type 1 AGN. We describe the evidence for absorption covering a wide range of column densities, ionization and dynamics, and discuss the growing evidence for partial-covering absorption from data at energies > 10 keV. Such absorption can also explain the observed X-ray spectral curvature and variability in AGN at lower energies and is likely an important factor in shaping the observed properties of this class of source. Consideration of self-consistent models for local AGN indicates that X-ray spectra likely comprise a combination of absorption and reflection effects from material originating within a few light days of the black hole as well as on larger scales. It is likely that AGN X-ray spectra may be strongly affected by the presence of disk-wind outflows that are expected in systems with high accretion rates, and we describe models that attempt to predict the effects of radiative transfer through such winds, and discuss the prospects for new data to test and address these ideas.Comment: Accepted for publication in the Astronomy and Astrophysics Review. 58 pages, 9 figures. V2 has fixed an error in footnote

The effect of cigarette smoke exposure on the development of inflammation in lungs, gut and joints of TNFΔARE mice

The inflammatory cytokine TNF-alpha is a central mediator in many immune-mediated diseases, such as Crohn's disease (CD), spondyloarthritis (SpA) and chronic obstructive pulmonary disease (COPD). Epidemiologic studies have shown that cigarette smoking (CS) is a prominent common risk factor in these TNF-dependent diseases. We exposed TNF Delta ARE mice; in which a systemic TNF-alpha overexpression leads to the development of inflammation; to 2 or 4 weeks of air or CS. We investigated the effect of deregulated TNF expression on CS-induced pulmonary inflammation and the effect of CS exposure on the initiation and progression of gut and joint inflammation. Upon 2 weeks of CS exposure, inflammation in lungs of TNF Delta ARE mice was significantly aggravated. However, upon 4 weeks of CS-exposure, this aggravation was no longer observed. TNF Delta ARE mice have no increases in CD4+ and CD8+ T cells and a diminished neutrophil response in the lungs after 4 weeks of CS exposure. In the gut and joints of TNF Delta ARE mice, 2 or 4 weeks of CS exposure did not modulate the development of inflammation. In conclusion, CS exposure does not modulate gut and joint inflammation in TNF Delta ARE mice. The lung responses towards CS in TNF Delta ARE mice however depend on the duration of CS exposure

Endoscopic treatment of prepatellar bursitis

Operative treatment of prepatellar bursitis is indicated in intractable bursitis. The most common complication of surgical treatment for prepatellar bursitis is skin problems. For traumatic prepatellar bursitis, we propose a protocol of outpatient endoscopic surgery under local anaesthesia. From September 1996 to February 2001, 60 cases of failed nonoperative treatment for prepatellar bursitis were included. The average age was 33.5 ± 11.1 years (range 21–55). The average operation duration was 18 minutes. Two to three mini-arthroscopic portals were used in our series. No sutures or a simple suture was needed for the portals after operation. After follow-up for an average of 36.3 months, all patients are were symptom-free and had regained knee function. None of the population had local tenderness or hypo-aesthesia around their wound. Their radiographic and sonographic examinations showed no recurrence of bursitis. Outpatient arthroscopic bursectomy under local anaesthesia is an effective procedure for the treatment of post-traumatic prepatellar bursitis after failed conservative treatments. Both the cosmetic results and functional results were satisfactory

Steroid-refractory ulcerative colitis treated with corticosteroids, metronidazole and vancomycin: a case report

BACKGROUND: Increasing evidence elucidating the pathogenic mechanisms of ulcerative colitis (UC) has accumulated and the disease is widely assumed to be the consequence of genetic susceptibility and an abnormal immune response to commensal bacteria. However evidence regarding an infectious etiology in UC remains elusive. CASE PRESENTATION: We report a provocative case of UC with profound rheumatologic involvement directly preceded by Clostridium difficile infection and accompanying fever, vomiting, bloody diarrhea, and arthritis. Colonic biopsy revealed a histopathology suggestive of UC. Antibiotic treatment eliminated detectable levels of enteric pathogens but did not abate symptoms. Resolution of symptoms was procurable with oral prednisone, but tapering of corticosteroids was only achievable in combination therapy with vancomycin and metronidazole. CONCLUSIONS: An infectious pathogen may have both precipitated and exacerbated autoimmune disease attributes in UC, symptoms of which could be resolved only with a combination of corticosteroids, vancomycin and metronidazole. This may warrant the need for more perceptive scrutiny of C. difficile and the like in patients with UC

TL1A Selectively Enhances IL-12/IL-18-Induced NK Cell Cytotoxicity against NK-Resistant Tumor Targets

# The Author(s) 2010. This article is published with open access at Springerlink.com Introduction TL1A (TNFSF15) augments IFN-γ production by IL-12/IL-18 responsive human T cells. Its ligand, death domain receptor 3 (DR3), is induced by activation on T and NK cells. Although IL-12/IL-18 induces DR3 expression on most NK cells, addition of TL1A minimally increases IFN-

Serological Markers for Inflammatory Bowel Disease in AIDS Patients with Evidence of Microbial Translocation

Background: Breakdown of the gut mucosal barrier during chronic HIV infection allows translocation of bacterial products such as lipopolysaccharides (LPS) from the gut into the circulation. Microbial translocation also occurs in inflammatory bowel disease (IBD). IBD serological markers are useful in the diagnosis of IBD and to differentiate between Crohn's disease (CD) and ulcerative colitis (UC). Here, we evaluate detection of IBD serological markers in HIV-infected patients with advanced disease and their relationship to HIV disease markers.Methods IBD serological markers (ASCA, pANCA, anti-OmpC, and anti-CBir1) were measured by ELISA in plasma from AIDS patients (n = 26) with low CD4 counts (<300 cells/$\mu$l) and high plasma LPS levels, and results correlated with clinical data. For meta-analysis, relevant data were abstracted from 20 articles. Results: IBD serological markers were detected in approximately 65% of AIDS patients with evidence of microbial translocation. An antibody pattern consistent with IBD was detected in 46%; of these, 75% had a CD-like pattern. Meta-analysis of data from 20 published studies on IBD serological markers in CD, UC, and non-IBD control subjects indicated that IBD serological markers are detected more frequently in AIDS patients than in non-IBD disease controls and healthy controls, but less frequently than in CD patients. There was no association between IBD serological markers and HIV disease markers (plasma viral load and CD4 counts) in the study cohort. Conclusions: IBD serological markers may provide a non-invasive approach to monitor HIV-related inflammatory gut disease. Further studies to investigate their clinical significance in HIV-infected individuals are warranted

Biventricular Myocardial Fibrosis and Sudden Death in Patients With Brugada Syndrome.

BACKGROUND: Electrophysiological, imaging, and pathological studies have reported the presence of subtle structural abnormalities in hearts from patients with Brugada syndrome (BrS). However, data concerning disease involvement outside of the right ventricular outflow tract are limited. OBJECTIVES: This study sought to characterize the presence and distribution of ventricular myocardial fibrosis in a cohort of decedents experiencing sudden cardiac death caused by BrS. METHODS: The authors evaluated 28 whole hearts from consecutive sudden cardiac death cases attributed to BrS and 29 hearts from a comparator group comprised of noncardiac deaths (control subjects). Cardiac tissue from 6 regions across the right and left ventricle were stained with Picrosirius red for collagen and tissue composition was determined using image analysis software. Postmortem genetic testing was performed in cases with DNA retained for analysis. RESULTS: Of 28 BrS decedents (75% men; median age of death 25 years), death occurred in sleep or at rest in 24 of 28 (86%). The highest proportion of collagen was observed in the epicardial right ventricular outflow tract of the BrS group (23.7%; 95% CI: 20.8%-26.9%). Ventricular myocardium from BrS decedents demonstrated a higher proportion of collagen compared with control subjects (ratio 1.45; 95% CI: 1.22-1.71; P < 0.001), with no significant interactions with respect to sampling location or tissue layer. There was insufficient evidence to support differences in collagen proportion in SCN5A-positive cases (n = 5) when compared with control subjects (ratio 1.23; 95% CI: 0.75-1.43; P = 0.27). CONCLUSIONS: Brugada syndrome is associated with increased collagen content throughout right and left ventricular myocardium, irrespective of sampling location or myocardial layer