Publications by authors named "Rad R"

Epidemiological and experimental data demonstrate, that inflammation contributes significantly to pancreatic carcinogenesis. IL1beta, a pleiotropic cytokine produced by inflammatory cells and tumor cells, promotes cancer progression. Single nucleotide polymorphisms (SNPs) of the IL1beta promoter were found to be associated with an increased risk for certain cancers.

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Purpose: Ileal carcinoids are gut epithelial tumors originating from serotonin-containing enterochromaffin (EC) cells. Therapeutic options for effectively inhibiting the growth and spread of metastatic carcinoids are still limited. We aimed to identify the role of matrix metalloproteinases (MMPs) and their endogenous tissue inhibitors (TIMPs) during tumor development and metastasis.

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Background & Aims: Recognition of infection leads to induction of adaptive immunity through activation of antigen-presenting cells (APCs). Among APCs, dendritic cells (DCs) have the unique capacity to deliver antigens from the periphery to T cells in secondary lymphoid organs.

Methods: We analyzed molecular mechanisms of the Helicobacter pylori-induced APC activation in vitro and investigated the influence of Myd88 signaling on the phenotype of adaptive immunity to H pylori in a murine infection model.

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Regulatory T cells (Treg) are vital in maintaining the homeostasis of immune reactions. In chronic infections, such as schistosomiasis, it remains unclear whether engagement of the TLR family is required to induce Treg activity. Thus, we performed in vivo studies using TLR2-/- mice infected with Schistosoma mansoni and found elevated immunopathology, decreased egg burden and extended antigen-specific Th1 responses.

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Background: Regulatory T cells (T-reg cells) have been described as an important cell population in the UV treatment of inflammatory skin diseases.

Methods: We have treated five patients with generalized atopic eczema (AE) using medium-dose (15 cycles of 50 J/cm(2), total dose of 750 J/cm(2)) UVA1 therapy and have analyzed the skin-infiltrating T-cellular subsets before and after therapy. Skin biopsies were split for immunohistochemistry and Real-time PCR and analyzed for CD4, Fox-P3, GATA-3, and IL-10 transcription as well as for CD3, CD4, CD152, Fox-P3, and GITR staining.

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Background & Aims: Helicobacter pylori colonizes the human gastric mucosa of >50% of the world's population. Most of the patients have no overt clinical symptoms. However, the infection is invariably associated with the development of active chronic gastritis, leading in some cases to the development of peptic ulcer disease, distal gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma.

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Academic and industrial research continues to be focused on discovering new classes of compounds based on HTS. Post-HTS analyses need to prioritize compounds that are progressed to chemical probe or lead status. We report trends in probe, lead and drug discovery by examining the following categories of compounds: 385 leads and the 541 drugs that emerged from them; "active" (152) and "inactive" (1488) compounds from the Molecular Libraries Initiative Small Molecule Repository (MLSMR) tested by HTS; "active" (46) and "inactive" (72) compounds from Nature Chemical Biology (NCB) tested by HTS; compounds in the drug development phase (I, II, III and launched), as indexed in MDDR; and medicinal chemistry compounds from WOMBAT, separated into high-activity (5,784 compounds with nanomolar activity or better) and low-activity (30,690 with micromolar activity or less).

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Many strains of Helicobacter pylori are naturally competent for transformation and able to transfer chromosomal DNA among different isolates using a conjugation-like mechanism. In this study, we sought to determine whether H. pylori can transfer DNA into Campylobacter jejuni, a closely related species of the Campylobacterales group.

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Background: Expression of the Helicobacter pylori outer membrane protein HopH is regulated by phase variation within a CT dinucleotide repeat motif of the hopH gene.

Methods: To investigate the importance of HopH for bacterial pathogenicity, we performed a detailed functional genomic and population-based genetic characterization of this contingency locus.

Results: Sequencing of hopH in H.

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It has been proposed that the transcription factor RUNX3 is the product of a gastric tumour suppressor gene. We examined RUNX3 expression in gastric biopsies from 105 patients with different histological presentations. Surprisingly, immunohistochemical staining detected RUNX3 protein expression only in infiltrating leukocytes but not in the gastric epithelium.

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Background & Aims: Helicobacter pylori infects more than half of the world's population. In contrast to most other pathogens, the microbe persists for the virtual life of its host. It is unclear why the immune system is unable to eliminate the infection, but recent studies suggested that CD4+/CD25+/Foxp3+ regulatory T cells may be involved in this process.

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Chronic Helicobacter pylori infection is characterized by dense infiltration of the mucosa with neutrophilic granulocytes, lymphocytes, and monocytes/macrophages. Among these different cell types, T-lymphocytes are the most intriguing and crucial cells for the elimination of the bacteria. Previous studies have elucidated possible mechanisms on how bacteria could interfere with the human immune response and claimed that especially the secreted vacuolating toxin VacA may be responsible for the chronic persistence of the bacteria.

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Alternative splicing is emerging as a major new mechanism of functional regulation in mammals, and there is increasing evidence that human cancers often involve significant changes in alternative splicing. In some cases, these changes contribute functionally to the maintenance of the transformed state and could be useful as novel targets for anticancer therapy. In other cases, they reflect changes due to tumorigenesis and could be useful for diagnostic purposes.

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Background & Aims: Although Helicobacter pylori is recognized by the human immune system, the bacteria are not eliminated and lead to a chronic inflammation of the gastric mucosa.

Methods: We investigated the interaction of H. pylori with human lymphocytes.

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Helicobacter pylori strains harboring the vacAs1, cagA and babA2 have been associated with ulcer disease (UD). We compared the prevalence of these different genotypes and adhesive properties in H. pylori infected patients with UD in four European countries.

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Background: Infection of the gastric mucosa with Helicobacter pylori leads to increased apoptosis. Cytokines and receptors of the tumor necrosis factor (TNF) family are known to be involved in this process. The role that the death-inducing TNF- alpha -related apoptosis-inducing ligand (TRAIL) and its receptors play, in the context of H.

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Aim And Methods: Enterochromaffin (EC) cells, interspersed throughout the gastrointestinal mucosa, provide most of the serotonin of the body and control intestinal motility, secretion and absorption. We purified EC cells from the rat ileum by a combination of elutriation and density gradient centrifugation in order to characterize the function of this important cell type.

Results: Immunostaining showed that there were 84% serotonin-positive cells in the highly enriched EC fraction as compared with 12% in unfractionated cells, yielding a approximately sevenfold enrichment.

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Background And Aims: Recent studies linked cytokine gene polymorphisms to H pylori related gastric cancer development. The current study evaluated the role of cytokine gene polymorphisms for mucosal cytokine expression, the gastric inflammatory response, and bacterial colonisation during H pylori infection.

Patients And Methods: In 207 H pylori infected patients with chronic gastritis, polymorphisms at different loci of the interleukin (IL)-10, IL-1B, IL-1 receptor antagonist (IL-1RN), tumour necrosis factor (TNF)-A, and interferon (IFN)-G genes were genotyped by polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) analysis, and allelic discriminating TaqMan PCR.

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Helicobacter pylori infection leads to chronic gastric inflammation. The current study determined the response of human APCs, NK cells, and T cells toward the bacteria in vitro. Human monocyte-derived dendritic cells (DC) were incubated with bacteria for 48 h.

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Background And Aims: Gastric extranodal marginal zone B cell lymphoma of the mucosa associated lymphoid tissue (MALT)-type (MZBL) is a rare complication of Helicobacter pylori infection. Currently, no bacterial factor has been associated with the development of this disease. Our aim was to identify genes associated with lymphoma development.

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Cultured primary human keratinocytes were screened for their expression of various members of the toll-like receptor (TLR) family. Keratinocytes were found to constitutively express TLR1, TLR2, TLR3, TLR5, and TLR9 but not TLR4, TLR6, TLR7, TLR8, or TLR10 as shown by polymerase chain reaction analysis. The expression of the crucial receptor for signaling of staphylococcal compounds TLR2 was also confirmed by immunohistochemistry, in contrast to TLR4, which showed a negative staining pattern.

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