On the dynamics of nitrite, nitrate and other biomarkers of nitric oxide production in inflammatory bowel disease

Nitrite and nitrate are frequently used surrogate markers of nitric oxide (NO) production. Using rat models of acute and chronic DSS-induced colitis we examined the applicability of these and other NO-related metabolites, in tissues and blood, for the characterization of inflammatory bowel disease. Global NO dynamics were assessed by simultaneous quantification of nitrite, nitrate, nitroso and nitrosyl species over time in multiple compartments. NO metabolite levels were compared to a composite disease activity index (DAI) and contrasted with measurements of platelet aggregability, ascorbate redox status and the effects of 5-aminosalicylic acid (5-ASA). Nitroso products in the colon and in other organs responded in a manner consistent with the DAI. In contrast, nitrite and nitrate, in both intra- and extravascular compartments, exhibited variations that were not always in step with the DAI. Extravascular nitrite, in particular, demonstrated significant temporal instabilities, ranging from systemic drops to marked increases. The latter was particularly evident after cessation of the inflammatory stimulus and accompanied by profound ascorbate oxidation. Treatment with 5-ASA effectively reversed these fluctuations and the associated oxidative and nitrosative stress. Platelet activation was enhanced in both the acute and chronic model. Our results offer a first glimpse into the systemic nature of DSS-induced inflammation and reveal a greater complexity of NO metabolism than previously envisioned, with a clear dissociation of nitrite from other markers of NO production. The remarkable effectiveness of 5-ASA to abrogate the observed pattern of nitrite instability suggests a hitherto unrecognized role of this molecule in either development or resolution of inflammation. Its possible link to tissue oxygen consumption and the hypoxia that tends to accompany the inflammatory process warrants further investigation

Moderate performance of serum S100A12, in distinguishing inflammatory bowel disease from irritable bowel syndrome

<p>Abstract</p> <p>Background</p> <p>S100A12, a calcium-binding proinflammatory protein secreted by granulocytes, has been associated with different diseases of inflammatory origin, including inflammatory bowel disease (IBD). In this study, the utility of serum S100A12, in discriminating IBD from irritable bowel syndrome (IBS), was tested.</p> <p>Methods</p> <p>S100A12 serum levels were determined in 64 patients with ulcerative colitis (UC), 64 with Crohn's disease (CD) and 73 with IBS, by means of an enzyme-linked immunosorbent assay. S100A12 serum levels were evaluated with respect to the levels of known inflammatory markers and patients' characteristics.</p> <p>Results</p> <p>The median values of serum S100A12 levels were 68.2 ng/mL (range: 43.4-147.4) in UC, 70 ng/mL (41.4-169.8) in CD and 43.4 ng/mL (34.4-74.4) in IBS patients. UC and CD patients had significantly higher serum S100A12 levels compared to IBS patients (<it>P </it>= 0.001 for both comparisons). Moreover, a cut-off for serum S100A12 levels of 54.4 ng/mL could predict both UC and CD with a 66.7% sensitivity and a 64.4% specificity. The area under curve was estimated at 0.67 with a 95% confidence interval of 0.60-0.75 (<it>P </it>< 0.001). Considering standard activity indices, higher serum S100A12 levels in active compared to inactive IBD were observed, although the recorded difference did not reach statistical significance. C-reactive protein (CRP) and serum amyloid A (SAA) levels, showed a statistically significant positive correlation with S100A12 (r = 0.39, <it>P </it>= 0.001 and r = 0.23, <it>P </it>= 0.02 respectively).</p> <p>Conclusions</p> <p>Increased levels of circulating S100A12 are found in IBD, compared to IBS. When used to distinguish IBD from IBS adult patients, serum S100A12 levels exhibit moderate performance. On the other hand, serum S100A12 may serve as an inflammatory marker in IBD, since it is well correlated with CRP and SAA.</p

Enhanced platelet adhesion induces angiogenesis in intestinal inflammation and inflammatory bowel disease microvasculature

Although angiogenesis is viewed as a fundamental component of inflammatory bowel disease (IBD) pathogenesis, we presently lack a thorough knowledge of the cell type(s) involved in its induction and maintenance in the inflamed intestinal mucosa. This study aimed to determine whether platelet (PLT) adhesion to inflamed intestinal endothelial cells of human origin may favour angiogenesis. Unstimulated or thrombin-activated human PLT were overlaid on resting or tumour necrosis factor (TNF)-α-treated human intestinal microvascular endothelial cells (HIMEC), in the presence or absence of blocking antibodies to either vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule (ICAM)-1, integrin αvβ3, tissue factor (TF) or fractalkine (FKN). PLT adhesion to HIMEC was evaluated by fluorescence microscopy, and release of angiogenic factors (VEGF and soluble CD40L) was measured by ELISA. A matrigel tubule formation assay was used to estimate PLT capacity to induce angiogenesis after co-culturing with HIMEC. TNF-α up-regulated ICAM-1, αvβ3 and FKN expression on HIMEC. When thrombin-activated PLT were co-cultured with unstimulated HIMEC, PLT adhesion increased significantly, and this response was further enhanced by HIMEC activation with TNF-α. PLT adhesion to HIMEC was VCAM-1 and TF independent but ICAM-1, FKN and integrin αvβ3 dependent. VEGF and sCD40L were undetectable in HIMEC cultures either before or after TNF-α stimulation. By contrast, VEGF and sCD40L release significantly increased when resting or activated PLT were co-cultured with TNF-α-pre-treated HIMEC. These effects were much more pronounced when PLT were derived from IBD patients. Importantly, thrombin-activated PLT promoted tubule formation in HIMEC, a functional estimate of their angiogenic potential. In conclusion, PLT adhesion to TNF-α-pre-treated HIMEC is mediated by ICAM-1, FKN and αvβ3, and is associated with VEGF and sCD40L release. These findings suggest that inflamed HIMEC may recruit PLT which, upon release of pro-angiogenic factors, actively contribute to inflammation-induced angiogenesis

Inhibitory effect of genistein on the invasive potential of human cervical cancer cells via modulation of matrix metalloproteinase-9 and tissue inhibitiors of matrix metalloproteinase-1 expression

Background: One of the most challenging stumbling blocks for the treatment of cancer is the ability of cancer cells to break the natural barriers and spread from its site of origin to non-adjacent regional and distant sites, accounting for high cancer mortality rates. Gamut experimental and epidemiological data advocate the use of pharmacological or nutritional interventions to inhibit or delay various stage(s) of cancer such as invasion and metastasis. Genistein, a promising chemopreventive agent, has gained considerable attention for its powerful anti-carcinogenic, anti-angiogenic and chemosensitizing activities. Methods: In this study, the cytotoxic potential of genistein on HeLa cells by cell viability assay and the mode of cell death induced by genistein were determined by nuclear morphological examination, DNA laddering assay and cell cycle analysis. Moreover, to establish its inhibitory effect on migration of HeLa cells, scratch wound assay was performed and these results were correlated with the expression of genes involved in invasion and migration (MMP-9 and TIMP-1) by RT-PCR. Results: The exposure of HeLa cells to genistein resulted in significant dose- and time-dependent growth inhibition, which was found to be mediated by apoptosis and cell cycle arrest at G2/M phase. In addition, it induced migration-inhibition in a time-dependent manner by modulating the expression of MMP-9 and TIMP-1. Conclusion: Our results signify that genistein may be an effective anti-neoplastic agent to prevent cancer cell growth and invasion and metastasis. Therefore therapeutic strategies utilizing genistein could be developed to substantially reduce cancer morbidity and mortality. © 2012 Elsevier Ltd

Autoimmunogenicity of the helix-loop-helix DNA-binding domain

Nonimmunogenic character of native DNA, and its high immunogenicity when presented in complex with the DNA-binding proteins indicate that the latter might contain molecular triggers of anti-DNA response. To find if this is the case, we have evaluated the autoimmunogenic potential of the main DNA-binding domain of HIV-1 reverse transcriptase that belongs to the canonical helix-loop-helix type. BALB/c mice were immunized with a peptide representing the domain, alone or in complex with the fragmented human DNA in the presence of an adjuvant. Mice were assessed for specific antibodies, autoantibodies against a panel of self-antigens; glomerular immunoglobulin deposition; and for the signs of autoimmune disease, such as proteinuria, and changes in the blood compoments. Immunization with the adjuvanted peptide-DNA complex induced autoantibodies against double-stranded DNA, histones, heterochromatin, and kidney proteins; glomerular IgG and IgA deposition; proteinuria; thrombocytopenia, and anemia. Altogether, this identifies the helix-loop-helix DNA-binding domain as one of the molecular triggers of autoimmunity to DNA and DNA-associated proteins. The experiments cast new light on the role of the DNA-binding retroviral proteins in the induction of autoimmunity, and on the origins of autoimmune complications in the microbial infections in general. It also implies that choosing the DNA-binding proteins as vaccine candidates should be done with precaution

A comparative study of virtual reality hand-tracking and controllers

In recent years the popularity of virtual reality has grown immensely and with it have come some interesting technologies such as hand-tracking. Even though the virtual reality genre is still dominated by the standard input system, the controller, whether it is for entertainment or educational purposes, there seems to be a growing desire for alternatives. The goal of this Bachelor’s thesis was to find and compare the advantages and the disadvantages of the controller and hand-tracking. The theoretical part of this paper includes topics such as what is virtual reality, hand-tracking and what devices can utilize it and the requirements for the practical part. The practical part includes topics like the implementation, the player interview analysis and the in-game data analysis. For the purposes of this thesis, two identical games were created, one supporting controllers and the other one supporting hand-tracking. The game takes place in a ship’s control room and the player is given a set of tasks that need to be completed. While the participants were playing, their in-game actions were video recorded and once they finished playing, the participants were interviewed. According to the data, hand-tracking has a competitive advantage over controllers. Out the of nine participants, close to 90% of the players felt one of the positive experiences of hand-tracking is the freedom and the natural feeling of it

Kokemuksia Ihmeelliset vuodet -ryhmänhallintamenetelmän käytöstä Rauman varhaiskasvatuksessa

Opinnäytetyön tarkoituksena oli selvittää, millaisia kokemuksia Rauman varhaiskasvatuksen työntekijöillä on Ihmeelliset vuodet -ryhmänhallintamenetelmästä. Tavoitteena oli saada mahdollisimman monipuolisesti tietoa ja kokemuksia Ihmeelliset vuodet -ryhmänhallintamenetelmästä ja koulutuksesta sekä menetelmän käytöstä Rauman varhaiskasvatuksessa. Tutkimus toteutettiin laadullisena kyselytutkimuksena, joka kohdistettiin niille Rauman varhaiskasvatuksen työntekijöille, jotka olivat käyneet Ihmeelliset vuodet -ryhmänhallintamenetelmä koulutuksen. Ihmeelliset vuodet -ryhmänhallintamenetelmä on osa Ihmeelliset vuodet -ohjelmakokonaisuutta, joka on tarkoitettu lasten käytöshäiriöiden ennaltaehkäisyyn ja hoitoon. Menetelmä on tarkoitettu varhaiskasvatuksen henkilöstölle sekä muille lasten kanssa työskenteleville ammattilaisille. Ihmeelliset vuodet -ryhmänhallintamenetelmä antaa työkaluja toteuttaa sellaista varhaiskasvatusta, joka tukee lasten sosiaalista kehitystä, vähentää käytösongelmia ryhmässä ja vahvistaa oikeanlaista kasvatusilmapiiriä. Tutkimus osoitti, että työntekijät kokevat menetelmän vaikuttavan positiivisesti sekä lapsien että työntekijöiden toimintaan. Menetelmästä koettiin olevan myös paljon hyötyä arkityössä monissa eri tilanteissa. Kaikki tutkimukseen osallistuneet myös suosittelisivat koulutusta muille varhaiskasvatuksen ammattilaisille. Menetelmän käytössä nähtiin kuitenkin myös haasteita. Yhtenä merkittävänä haasteena koettiin uusien toimintatapojen omaksuminen osaksi arkea. Myös henkilöstön ylikuormittuminen ja koulutuksen liian vähäinen tarjonta nähtiin menetelmän käyttöä rajoittavina tekijöinä. Tutkimuksen tulokset olivat kuitenkin pääosin erittäin positiivissävytteisiä. Opinnäytetyötämme voitaisiin hyödyntää tulevaisuudessa Rauman varhaiskasvatuksen lisäkoulutuksen suunnittelussa ja resurssien jakamisessa