The influence of fibrin sealant on the healing colonic anastomosis : an experimental study in rats

The experiments described in this thesis were performed in order to find methods to influence and improve colonic anastomotic wound healing. It is known that inflammation may affect the healing of colonic anastomoses. Eicosanoids are known mediators of the inflammatory process, being a part of the healing process. In order to influence the healing process anti inflammatory drugs may be used. To evaluate the possible role of eicosanoids in uncomplicated healing of colon anastomosis we decided to measure eicosanoid synthesis in colon tissue and peritoneal macrophages. Activity of peritoneal macrophages was studied based on the HPLC profile of eicosanoids. Colon tissue was studied as well in order to compare both profiles to establish which cell type is active in the healing colon (Chapter IV). Colonic anastomoses may be covered with fibrin sealant in order to promote wound healing and prevent leakage. Presently, this is already performed in many clinical situations. However data from experimental animal studies are conflicting, and prospective clinical studies are lacking. The influence of human· and rat fibrin sealant on the mechanical strength en collagen metabolism of a sutured colonic anastomoses is investigated (Chapter V). Ischemia of the wound margins is a high-risk condition in the healing colonic anastomosis, with a considerable chance of anastomotic dehiscence. The effect of fibrin sealant on the healing ischemic anastomosis is tested (Chapter VI). Another known risk-factor is the presence of peritonitis. The role of fibrin sealant in the presence of faecal peritonitis is described in Chapter VII. A technical imperfect anastomosis may result in leakage of intestinal contents. In order to examen the effect of fib

Coupled cavities for enhancing the cross-phase modulation in electromagnetically induced transparency

We propose an optical double-cavity resonator whose response to a signal is similar to that of an Electromagnetically Induced Transparency (EIT) medium. A combination of such a device with a four-level EIT medium can serve for achieving large cross-Kerr modulation of a probe field by a signal field. This would offer the possibility of building a quantum logic gate based on photonic qubits. We discuss the technical requirements that are necessary for realizing a probe-photon phase shift of Pi caused by a single-photon signal. The main difficulty is the requirement of an ultra-low reflectivity beamsplitter and to operate a sufficiently dense cool EIT medium in a cavity.Comment: 10 pages, 5 figures, REVTeX, to appear in Phys. Rev. A (v2 - minor changes in discussion of experimental conditions

Dendritic cell immunotherapy followed by cART interruption during HIV-1 infection induces plasma protein markers of cellular immunity and neutrophil recruitment.

OBJECTIVES: To characterize the host response to dendritic cell-based immunotherapy and subsequent combined antiretroviral therapy (cART) interruption in HIV-1-infected individuals at the plasma protein level. DESIGN: An autologous dendritic cell (DC) therapeutic vaccine was administered to HIV-infected individuals, stable on cART. The effect of vaccination was evaluated at the plasma protein level during the period preceding cART interruption, during analytical therapy interruption and at viral reactivation. Healthy controls and post-exposure prophylactically treated healthy individuals were included as controls. METHODS: Plasma marker ('analyte') levels including cytokines, chemokines, growth factors, and hormones were measured in trial participants and control plasma samples using a multiplex immunoassay. Analyte levels were analysed using principle component analysis, cluster analysis and limma. Blood neutrophil counts were analysed using linear regression. RESULTS: Plasma analyte levels of HIV-infected individuals are markedly different from those of healthy controls and HIV-negative individuals receiving post-exposure prophylaxis. Viral reactivation following cART interruption also affects multiple analytes, but cART interruption itself only has only a minor effect. We find that Thyroxine-Binding Globulin (TBG) levels and late-stage neutrophil numbers correlate with the time off cART after DC vaccination. Furthermore, analysis shows that cART alters several regulators of blood glucose levels, including C-peptide, chromogranin-A and leptin. HIV reactivation is associated with the upregulation of CXCR3 ligands. CONCLUSIONS: Chronic HIV infection leads to a change in multiple plasma analyte levels, as does virus reactivation after cART interruption. Furthermore, we find evidence for the involvement of TBG and neutrophils in the response to DC-vaccination in the setting of HIV-infection

Advanced glycation end products as a biomarker for incisional hernia

Background: Incisional hernia is one of the most frequent complications after abdominal surgery, with incidences up to 30%. A reliable biomarker for the prediction of this complication is lacking. Advanced glycosylation end products (AGEs), also known as non-enzymatic collagen crosslinks, are correlated with aging, smoking, hyperglycemia, hyperlipidemia and oxidative stress. In this study the accumulation of AGEs and the relation between AGEs and incisional hernia were investigated. Materials and methods: In an explorato

Dendritic cell immunotherapy followed by cART interruption during HIV-1 infection induces plasma protein markers of cellular immunity and neutrophil recruitment

Objectives To characterize the host response to dendritic cell-based immunotherapy and subsequent combined antiretroviral therapy (cART) interruption in HIV-1-infected individuals at the plasma protein level. Design An autologous dendritic cell (DC) therapeutic vaccine was administered to HIV-infected individuals, stable on cART. The effect of vaccination was evaluated at the plasma protein level during the period preceding cART interruption, during analytical therapy interruption and at viral reactivation. Healthy controls and post-exposure prophylactically treated healthy individuals were included as controls. Methods Plasma marker (‘analyte’) levels including cytokines, chemokines, growth factors, and hormones were measured in trial participants and control plasma samples using a multiplex immunoassay. Analyte levels were analysed using principle component analysis, cluster analysis and limma. Blood neutrophil counts were analysed using linear regression. Results Plasma analyte levels of HIV-infected individuals are markedly different from those of healthy controls and HIV-negative individuals receiving post-exposure prophylaxis. Viral reactivation following cART interruption also affects multiple analytes, but cART interruption itself only has only a minor effect. We find that Thyroxine-Binding Globulin (TBG) levels and late-stage neutrophil numbers correlate with the time off cART after DC vaccination. Furthermore, analysis shows that cART alters several regulators of blood glucose levels, including C-peptide, chromogranin-A and leptin. HIV reactivation is associated with the upregulation of CXCR