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BACKGROUND: Cognitive performance was compared in the genetically and neurobiologically related disorders of Tourette's syndrome (TS) and obsessive-compulsive disorder (OCD), in three domains of executive function: planning, decision-making and inhibitory response control. METHOD: Twenty TS patients, twenty OCD patients and a group of age- and IQ-matched normal controls completed psychometric and computerized cognitive tests and psychiatric rating scales. The cognitive tests were well-characterized in terms of their sensitivity to other fronto-striatal disorders, and included pattern and spatial recognition memory, attentional set-shifting, and a Go/No-go set-shifting task, planning, and decision-making. RESULTS: Compared to controls, OCD patients showed selective deficits in pattern recognition memory and slower responding in both pattern and spatial recognition, impaired extra-dimensional shifting on the set-shifting test and impaired reversal of response set on the Go/No-go test. In contrast, TS patients were impaired in spatial recognition memory, extra-dimensional set-shifting, and decision-making. Neither group was impaired in planning. Direct comparisons between the TS and OCD groups revealed significantly different greater deficits for recognition memory latency and Go/No-go reversal for the OCD group, and quality of decision-making for the TS group. CONCLUSIONS: TS and OCD show both differences (recognition memory, decision-making) and similarities (set-shifting) in selective profiles of cognitive function. Specific set-shifting deficits in the OCD group contrasted with their intact performance on other tests of executive function, such as planning and decision-making, and suggested only limited involvement of frontal lobe dysfunction, possibly consistent with OCD symptomatology. [ABSTRACT FROM AUTHOR]

Rationale . Cystic fibrosis related diabetes (CFRD) is the most common comorbidity in patients with CF. In spite of increased screening, diagnosis, and treatment of CFRD, the mortality rate in patients with CFRD still far exceeds the mortality rate in those without CFRD. Guidelines suggest that screening for CFRD be performed annually using the 2-hour 75-gram oral glucose tolerance test (OGTT). Adherence to recommended screening has been poor, with only approximately one-quarter of adults with CF undergoing OGTT in 2014. Use of continuous glucose monitoring (CGM) for diagnosis may become an alternative. Objectives . Our objective was to determine whether abnormal CGM predicts subsequent development of CFRD, lung function, and body mass index (BMI) decline and increased rate of CF pulmonary exacerbations in adults with CF. Methods . In a prospective single center pilot trial from September 2009 to September 2010, 21 adult patients due for routine OGTT were recruited to complete simultaneous 3-day CGM and 2-hour 75 gram OGTT. Subsequently, clinical information was reviewed from 2008 to 2015. Conclusions . There was a moderate correlation between interpreted results of 2-hour OGTT and CGM ( p = 0.03); CGM indicated a greater level of glucose impairment than OGTT. Glucose >200 mg/dL by CGM predicted development of CFRD ( p = 0.0002)., Competing Interests: The authors have no competing interests with any companies whose products or services may be discussed in this article.

Invading colorectal cancer (CRC) cells have acquired the capacity to break free from their sister cells, infiltrate the stroma, and remodel the extracellular matrix (ECM). Characterizing the biology of this phenotypically distinct group of cells could substantially improve our understanding of early events during the metastatic cascade. Tumor invasion is a dynamic process facilitated by bidirectional interactions between malignant epithelium and the cancer associated stroma. In order to examine cell-specific responses at the tumor stroma-interface we have combined organotypic co-culture and laser micro-dissection techniques. Organotypic models, in which key stromal constituents such as fibroblasts are 3-dimensionally co-cultured with cancer epithelial cells, are highly manipulatable experimental tools which enable invasion and cancer-stroma interactions to be studied in near-physiological conditions. Laser microdissection (LMD) is a technique which entails the surgical dissection and extraction of the various strata within tumor tissue, with micron level precision. By combining these techniques with genomic, transcriptomic and epigenetic profiling we aim to develop a deeper understanding of the molecular characteristics of invading tumor cells and surrounding stromal tissue, and in doing so potentially reveal novel biomarkers and opportunities for drug development in CRC.

The oncogene microRNA-21 (miRNA; miR-21) is overexpressed in most solid organ tumours; however, a recent examination of stage II colorectal cancer (CRC) specimens suggests this may be a stromal phenomenon and not only a feature of cancer cells. In vitro and in vivo studies show that miR-21 has potent pro-metastatic effects in various malignant carcinoma cell lines. The tumour microenvironment has also been identified as a key actor during the metastatic cascade; however to date the significance of deregulated miR-21 expression within the cancer-associated stroma has not been examined. In the present study, a quantitative RT-PCR-based analysis of laser microdissected tissue confirmed that miR-21 expression is associated with a four-fold mean increase in CRC stroma compared with normal tissue. In situ hybridisation using locked nucleic acid probes localised miR-21 expression predominantly to fibroblasts within tumour-associated stroma. To study the molecular and biological impact of deregulated stromal miR-21 in CRC, stable ectopic expression was induced in immortalised fibroblasts. This resulted in upregulated α-smooth muscle actin expression implying miR-21 overexpression is driving the fibroblast-to-myofibroblast transdifferentiation. Conditioned medium from miR-21-overexpressing fibroblasts protected CRC cells from oxaliplatin-induced apoptosis and increased their proliferative capacity. 3D organotypic co-cultures containing fibroblasts and CRC cells revealed that ectopic stromal miR-21 expression was associated with increased epithelial invasiveness. Reversion-inducing cysteine-rich protein with kazal motifs, an inhibitor of matrix-remodelling enzyme MMP2, was significantly downregulated by ectopic miR-21 in established and primary colorectal fibroblasts with a reciprocal rise in MMP2 activity. Inhibition of MMP2 abrogated the invasion-promoting effects of ectopic miR-21. This data, which characterises a novel pro-metastatic mechanism mediated by miR-21 in the CRC stroma, highlights the importance of miRNA deregulation within the tumour microenvironment and identifies a potential application for stromal miRNAs as biomarkers in cancer.

Background: Thalidomide, one of whose activities is to inhibit Tumour Necrosis Factor (TNF)-α production, has been reported to be an effective treatment for refractory inflammatory bowel disease (IBD). TNF-α driven production of matrix metalloproteinase (MMP)-3 by gut lamina propria mononuclear cells (LPMCs) is a major pathway of tissue injury in IBD; however the effect of thalidomide and newer more potent immunomodulatory derivatives on this pathway has not been studied., Aim: To investigate the effect of thalidomide, CC-4047 (pomalidomide), CC-5013 (lenalidomide), and CC-10004 (apremilast) on gut LPMC TNFα and MMP-3 production in patients with IBD., Methods: Gut LPMCs and myofibroblasts were isolated from patients with IBD, and cultured with thalidomide, CC-4047, CC-5013, and CC-10004. MMP-3 and TIMP-1 levels were determined by western blotting and real-time PCR, and TNF-α levels by ELISA., Results: CC-10004 significantly reduced both TNF-α production and MMP-3 production by cultured LPMCs. Thalidomide and CC-4047 and CC-5013 had no significant effect on the production of TNF-α or MMP-3 by LPMCs., Conclusion: These results provides a mechanistic rationale for both the failure of lenalidomide (CC-5013) in a recent randomised controlled trial in Crohn's disease, and for the evaluation of CC-10004 as a novel oral therapy in the treatment of CD and UC.

Background and Aims: In addition to its crucial role in dampening tissue-damaging immune responses in the gut, transforming growth factor beta (TGFbeta) is a potent profibrogenic agent inducing collagen synthesis and regulating the balance between matrix-degrading matrix metalloproteinases (MMPs) and their inhibitors (TIMPs). TGFbeta signalling was investigated by analysis of Smad proteins and MMPs/TIMPs in the mucosa overlying strictures in patients with Crohn's disease (CD)., Methods: Specimens were collected from macroscopically normal mucosa overlying strictured and non-strictured gut of patients with fibrostenosing CD. Isolated myofibroblasts were cultured with anti-TGFbeta blocking antibody or TGF beta 1. TGFbeta transcripts were analysed by quantitative reverse transcription-PCR (RT-PCR). Smad proteins and MMPs were determined by immunoblotting. MMP-12 activity was measured by a real-time MMP-12 activity assay. An in vitro wound-healing scratch assay was used to assess myofibroblast migration., Results: TGFbeta transcripts, phosphorylated Smad2-Smad3 (pSmad2-3) and TIMP-1 proteins were higher in mucosa overlying strictures than in mucosa overlying non-strictured areas. In contrast, mucosa overlying strictured gut had lower expression of Smad7, MMP-12 and MMP-3. Myofibroblasts from mucosa overlying strictured gut showed higher TGFbeta transcripts, a greater pSmad2-3 response to TGFbeta, increased TIMP-1, lower Smad7, increased collagen production and reduced migration ability compared with myofibroblasts from mucosa overlying non-strictured gut. TGFbeta blockade increased myofibroblast MMP-12 production and migration, more obviously in myofibroblasts isolated from mucosa overlying non-strictured compared with strictured gut., Conclusions: Changes in TGF-beta signalling and MMP production were identified in the mucosa overlying strictures in CD which may give a window into the process of fibrosis.

Background and Aims: The role of transforming growth factor beta (TGFbeta) in inhibiting T cell function in the normal gut has been studied in animal models. However, the impact of TGFbeta inhibition on T cells in the normal human gut remains poorly understood. The effect of TGFbeta blockade in normal intestinal biopsies grown ex vivo and lamina propria mononuclear cells (LPMCs) on T-bet, a T-box transcription factor required for T helper cell type (Th)1 differentiation, interferon gamma (IFN gamma) production, T cell apoptosis and matrix metalloproteinase (MMP)-3 production has therefore been tested., Methods: TGFbeta transcripts were determined by quantitative reverse transcription-PCR in laser-captured gut epithelium and lamina propria. Biopsies and LPMCs were cultured with anti-TGFbeta neutralising antibody. After 24 h culture, T-bet was determined by immunoblotting, and T cell apoptosis was assessed by flow cytometry. IFN gamma, tumour necrosis factor alpha (TNFalpha), interleukin (IL) 2, IL6, IL8, IL10, IL12p70 and IL17 were measured by ELISA. MMP-3 and tissue inhibitor of matrix metalloproteinase (TIMP)-1 were assessed by immunoblotting., Results: A higher number of TGFbeta transcripts was found in the lamina propria than in the epithelium in normal gut. T-bet expression was significantly higher in biopsies and LPMCs cultured with anti-TGFbeta antibody than in those cultured with control antibody. TGFbeta blockade downregulated T cell apoptosis, and induced a significant increase in IFN gamma, TNFalpha, IL2, IL6, IL8 and IL17 production. A higher expression of MMP-3, but not TIMP-1, was observed in the tissue and supernatant of biopsies treated with anti-TGFbeta antibody., Conclusions: The findings support a crucial role for TGFbeta in dampening T cell-mediated tissue-damaging responses in the human gut.

Background: In both ulcerative colitis (UC) and Crohn's disease (CD) there is a marked increase in mucosal IgG plasma cells (PC), although their precise role is not well established. In this study we isolated gut PCs from patients with IBD and normal controls and analyzed cytokine production, matrix metalloproteinase (MMP)-3 and tissue inhibitor of metalloproteinase (TIMP)-1 production, and PC longevity ex vivo., Methods: Lamina propria mononuclear cells (LPMCs) were isolated from patients with CD (n = 19), UC (n = 27), and normal controls (n = 42). PCs were further selected by immunomagnetic isolation using CD138 microbeads. Cytokine, MMP-3, and TIMP-1 expression was investigated by Taqman polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), Western blotting, and confocal microscopy. PC lifespan in vitro was studied by ELISpot analysis., Results: PCs from both controls and IBD patients contained high levels of transcripts for TGFbeta, whereas they did not contain significant transcripts for IL-4, IL-5, IL-10, IFNgamma, TNF, or IL-12p40. PCs from patients with CD and UC expressed significantly higher levels of MMP-3 protein and transcripts than controls (P < 0.0001). The vast majority of MMP-3-expressing PCs were IgG+ve. In culture, IgA PCs from both IBD patients and controls persisted for only a few days, but IgG PCs from IBD patients persisted for at least 3 weeks., Conclusions: We have demonstrated that IgG PCs from patients with IBD express large amounts of MMP-3 and that they appear to be long-lived. These results identify a new pathway by which IgG PCs may damage the gut.

Citrobacter rodentium is a natural mouse pathogen related to enteropathogenic and enterohemorrhagic Escherichia coli. We have previously utilized bioluminescence imaging (BLI) to determine the in vivo colonization dynamics of C. rodentium. However, due to the oxygen requirement of the bioluminescence system and the colonic localization of C. rodentium, in vivo localization studies were performed using harvested organs. Here, we report the detection of bioluminescent C. rodentium and commensal E. coli during colonization of the gastrointestinal tract in intact living animals. Bioluminescence was dependent on intact blood circulation, suggesting that the colonic environment is not anaerobic but nanaerobic. In addition, BLI revealed that C. rodentium colonizes the rectum, a site previously unreported for this pathogen.

Infection of mice with the intestinal bacterial pathogen Citrobacter rodentium results in colonic mucosal hyperplasia and a local Th1 inflammatory response similar to that seen in mouse models of inflammatory bowel disease. Matrix metalloproteinases (MMPs) have been shown to mediate matrix remodeling and cell migration during tissue injury and repair in the intestine. We have previously shown enhanced pathology in infected TNFRp55-/-, IL-12p40-/-, and IFN-gamma-/- mice, and here we show that this is associated with an increase in stromelysin-1 (MMP3) transcripts in colonic tissues. We have therefore investigated the role of MMP3 in colonic mucosal hyperplasia and the local Th1 responses using MMP3-/- mice. In MMP3-/- mice, similar mucosal thickening was observed after infection as in wild-type (WT) mice. Colonic tissues from MMP3-/- mice showed a compensatory increase in the expression of other MMP transcripts, such as MMP7 and MMP12. However, MMP3-/- mice showed delayed clearance of bacteria and delayed appearance of CD4+ T lymphocytes into intestinal lamina propria. CSFE-labeled mesenteric lymph node CD4+ T lymphocytes from infected WT mice migrated in fewer numbers into the mesenteric lymph nodes and colon of MMP3-/- mice than into those of WT mice. These studies show that mucosal remodeling can occur in the absence of MMP3, but that MMP3 plays a role in the migration of CD4+ T lymphocytes to the intestinal mucosa.

The indigenous bacterial microflora colonize the gut at birth and remain there throughout life. Approximately 10(14) bacteria are present in the ileum and colon and they are clearly immunogenic. The evidence is strong that the vast majority of IgA plasma cells in normal human gut are responding to the antigens of the flora, and although the flora is also responsible for producing the large numbers of T cells which are present in the gut of healthy individuals, the types of T cell response which the flora elicits are less well understood. A major challenge for the immune system is to distinguish between the antigens of the flora and the antigens of pathogens. There is also a growing realization that the normal flora can also influence gene expression in antigen-presenting cells in the gut and so set the context in which T cells respond to food antigen and vaccines.