Search results for "Pathogen"
showing 10 items of 1657 documents
From Immunogenic Mechanisms to Novel Therapeutic Approaches in Inflammatory Bowel Disease
2006
Crohn’s disease (CD) and ulcerative colitis (UC) are the two most common forms of chronic inflammatory bowel disease (IBD). The etiology of IBD is still unclear and should be considered as multi-factorial according to recent studies.1 Genetic factors seem to play a pathogenetic role as well as environmental, infectious and immulogical factors. Substantial progress, however, has been made in the understanding of the pathogenesis of IBD during the past years persuing the view, that IBD could result from disturbances of the intestinal barrier and a pathologic activation of the intestinal immune response towards luminal, bacterial antigens. This paradigm has led to the identification of key pla…
Pathogenesis of inflammatory bowel disease: transcription factors in the spotlight.
1998
See article on page 477 Dysregulated cytokine production by mucosal lymphocytes and macrophages has been implicated in the pathogenesis of both Crohn’s disease and ulcerative colitis, the two major forms of human inflammatory bowel disease (IBD).1 Over the past few years, various murine models of chronic intestinal inflammation resembling IBD have been discovered which have provided important clues as to the nature of this dysregulation and to its possible treatment with cytokines.2 Thus, in studies of several of the models most closely resembling Crohn’s disease it has been shown that production of large amounts of Th1-type cytokines—for example, interferon γ, by T cells is a major and ess…
Importance of HLA-DR+ and CD1a+ Epidermal Cells for Cytokine Production in Psoriasis
1995
Psoriasis is an inflammatory skin disease characterised by marked hyperproliferation of keratinocytes in association with vascular expansion, leukocyte infiltration and lymphocyte activation1. Cytokines are thought to play a pivotal role in the pathogenesis. It is speculated that a dysregulation of the cytokine network involving tumor-necrosis-factor-a (TNF-α), interleukin-6 (IL-6) and interleukin-8 (IL-8) might be the basic mechanism of the psoriatic inflammatory response2. TNF-α is the prototype of a proinflammatory peptide exerting immunomodulatory effects. IL-6 is a multifunctional cytokine with a broad range of biological functions in both acute and chronic inflammatory reactions. IL-8…
Sepsis in head and neck cancer patients treated with chemotherapy and radiation: literature review and consensus
2015
Abstract: The reporting of infection/sepsis in chemo/radiation-treated head and neck cancer patients is sparse and the problem is underestimated. A multidisciplinary group of head and neck cancer specialists from Italy met with the aim of reaching a consensus on a clinical definition and management of infections and sepsis. The Delphi appropriateness method was used for this consensus. External expert reviewers then evaluated the conclusions carefully according to their area of expertise. The paper contains seven clusters of statements about the clinical definition and management of infections and sepsis in head and neck cancer patients, which had a consensus. Furthermore, it offers a revie…
Data from: Temporal dynamics of Puumala hantavirus infection in cyclic populations of bank voles
2017
Understanding the dynamics of zoonotic pathogens in their reservoir host populations is a prerequisite for predicting and preventing human disease epidemics. The human infection risk of Puumala hantavirus (PUUV) is highest in northern Europe, where populations of the rodent host (bank vole, Myodes glareolus) undergo cyclic fluctuations. We conducted a 7-year capture-mark-recapture study to monitor seasonal and multiannual patterns of the PUUV infection rate in bank vole populations exhibiting a 3-year density cycle. Infected bank voles were most abundant in mid-winter months during years of increasing or peak host density. Prevalence of PUUV infection in bank voles exhibited a regular, seas…
Repression of Human Papillomavirus Oncogene Expression under Hypoxia Is Mediated by PI3K/mTORC2/AKT Signaling
2019
Oncogenic HPV types are major human carcinogens. Under hypoxia, HPV-positive cancer cells can repress the viral E6/E7 oncogenes and induce a reversible growth arrest. This response could contribute to therapy resistance, immune evasion, and tumor recurrence upon reoxygenation. Here, we uncover evidence that HPV oncogene repression is mediated by hypoxia-induced activation of canonical PI3K/mTORC2/AKT signaling. AKT-dependent downregulation of E6/E7 is only observed under hypoxia and occurs, at least in part, at the transcriptional level. Quantitative proteome analyses identify additional factors as candidates to be involved in AKT-dependent E6/E7 repression and/or hypoxic PI3K/mTORC2/AKT ac…
The Role of Lectins in Finfish: A Review
2019
The immune system of vertebrates involves both innate and acquired immune responses. The innate immunity is more generalized with robust response whereas the other has a highly specific response to infectious pathogens. Because of the lack of specialized lymphatic organs, innate immunity is an important mode of defense in fishes. The less specific innate immune system acts mainly through complement pathway which depends on pattern-based recognition of “self” and “non-self” targets by host lectins and associated proteins. This ultimately results in the clearance of target cells. Lectins are glycoproteins which possess at least one carbohydrate recognition domain (CRD) that specifically and r…
Laccases: structure, reactions, distribution
2004
Laccases (EC 1.10.3.2, p-diphenol: dioxygen oxidoreductases) are multi-copper proteins that use molecular oxygen to oxidize various aromatic and non-aromatic compounds by a radical-catalyzed reaction mechanism. The enzymes are involved in the pathogenicity, immunity and morphogenesis of organisms and in the metabolic turnover of complex organic substances such as lignin or humic matter. Owing to their high non-specific oxidation capacity, laccases are useful biocatalysts for diverse biotechnological applications. Until recently, laccases were only found in eukaryotes (fungi, higher plants, insects), but now there is strong evidence for their widespread distribution in prokaryotes and the fi…
Identification and role of inflammatory oxygen free radicals in cardiac ischemia and reperfusion injury
2003
Prolonged myocardial ischemia results in a variety of severe cellular, metabolic and ultra-structural damages. It is therefore generally accepted that reperfusion is an absolute prerequisite for the survival of ischemic tissue. However, reperfusion may precipitate arrhythmias, cause myocardial stunning and accelerate necrotic process. Oxygen free radicals have been suggested as possible mediators of reperfusioninduced injury and there is circumstantial evidence that supports this hypothesis. Indirect evidence in support of this concept derives from studies in which antioxidant enzymes, enzyme inhibitors, free radical scavengers and iron chelators are able to protect against reperfusion inju…
ChemInform Abstract: Omphalotins E-I, Five Oxidatively Modified Nematicidal Cyclopeptides from Omphalotus olearius.
2009
Omphalotins E–I, oxidatively modified cyclic dodecapeptides, were isolated from mycelial extracts of the basidiomycete Omphalotus olearius, and their structures were determined by NMR spectroscopic and MS methods. Four of the five omphalotins contained an unprecedented N-hydroxylated tricyclic tryptophan derivative. All compounds exhibited strong and selective nematicidal activity against the plant pathogen Meloidogyne incognita with LD90 values between 2 and 5 μg mL–1. Cytotoxic activities were not detected up to 50 μg mL–1. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)