Search results for "Intracellular signal transduction"
showing 10 items of 11 documents
Expression of the tumor necrosis factor receptor—associated factors 1 and 2 and regulation of the nuclear factor—kB antiapoptotic activity in human g…
2005
Object. Tumor necrosis factor receptor (TNFR)—associated factors (TRAFs) are a recently established group of proteins involved in the intracellular signaling of the TNFR superfamily members. The TRAFs have been implicated in promoting cell survival through the activation of transcription factor nuclear factor (NF)—κB. The authors investigated the expression of NF-κB, caspase 3, TRAF1, TRAF2, and TRAF-associated NF-κB activator/TRAF—interacting protein (TANK/I-TRAF), a regulator of TRAF activity, in human gliomas. Methods. Tumor samples were obtained in 27 adult patients harboring seven low-grade gliomas, nine anaplastic astrocytomas, and 11 glioblastomas multiforme. The NF-κB activation was…
Intracellular signal transduction pathways in sponges.
1990
Abstract Sponges are the lowest multicellular eukaryotic organisms. Due to the relatively low specialization, and concomitantly the high differentiation and dedifferentiation potency of their cells, the sponge cell system has proven to be a useful model to study the mechanism of cell-cell adhesion on molecular levels. Results of detailed biochemical and cell biological studies with the main cell adhesion molecules, the aggregation factor (AF) and the aggregation receptor, led to the formation of the modulation theory of cell adhesion. The events of cell adhesion are contigent on a multiplicity of precisely coordinated intracellular signal transduction pathways. Using the marine sponge Geodi…
Microcirculatory dysfunction in sepsis: a pathogenetic basis for therapy?
2000
Sepsis is a frequent complication of multiple organ dysfunction syndrome and remains a major problem of intensive care medicine. It is also a common factor in the final cause of death in hospital populations. Clinical observations, assisted by invasive monitoring techniques as well as pathological-anatomical studies, clearly indicate that microcirculatory dysfunction lies at the centre of sepsis pathogenesis. Numerous animal models, from rodents to primates, many of which employ bacteria or their toxins, especially endotoxins, have helped to shed light on the pathomechanisms leading to this dysregulation in the peripheral circulation. Among these are activation of humoral and cellular infla…
Differential TNF-Signaling in Chronic Inflammatory Disorders
2004
TNF-alpha is a pleiotropic cytokine with strong proinflammatory and immunomodulatory properties. TNF-alpha plays a critical role in many acute or chronic inflammatory diseases and anti-TNF-strategies have proven to be clinically effective. Two TNF-specific cell surface receptors TNF-R1 and TNF-R2 have been identified and the function of these receptors and the downstream intracellular signal transduction pathways have been extensively studied in vitro. For a long time TNF-R1 was considered to be the predominant mediator of TNF-signaling, whereas TNF-R2 was ascribed only auxilliary function. However, there is increasing clinical and experimental evidence for an important independent role of …
Lactoferricin B-derived peptides with inhibitory effects on ECE-dependent vasoconstriction
2010
Endothelin-converting enzyme (ECE), a key peptidase in the endothelin (ET) system, cleaves inactive big ET-1 to produce active ET-1, which binds to ET(A) receptors to exert its vasoconstrictor and pressor effects. ECE inhibition could be beneficial in the treatment of hypertension. In this study, a set of eight lactoferricin B (LfcinB)-derived peptides, previously characterized in our laboratory as angiotensin-converting enzyme (ACE) inhibitory peptides, was examined for their inhibitory effects on ECE. In vitro inhibitory effects on ECE activity were assessed using both the synthetic fluorogenic peptide substrate V (FPS V) and the natural substrate big ET-1. To study vasoactive effects, an…
Effects of Kaempferol and Myricetin on Inducible Nitric Oxide Synthase Expression and Nitric Oxide Production in Rats
2010
Abstract: When administered as drugs or consumed as food components, polyphenolic compounds synthesized in plants interfere with intracellular signal transduction pathways, including pathways of nitric oxide synthase expression. However, effects of these compounds in vivo do not always correlate with nitric oxide synthase-inhibiting activities revealed in experiments with cultured cells. The initial goal of this work was to compare effects of flavonoids kaempferol and myricetin on inducible nitric oxide synthase mRNA and protein expression monitored by real-time RT-PCR and immunohistochemistry and to evaluate the impact of these effects on nitric oxide production in rat organs measured by …
Review: How was metazoan threshold crossed? The hypothetical Urmetazoa.
2001
The origin of Metazoa remained — until recently — the most enigmatic of all phylogenetic problems. Sponges [Porifera] as ‘living fossils’, positioned at the base of multicellular animals, have been used to answer basic questions in metazoan evolution by molecular biological techniques. During the last few years, cDNAs/genes coding for informative proteins have been isolated and characterized from sponges, especially from the marine demosponges Suberites domuncula and Geodia cydonium. The analyses of their deduced amino acid sequences allowed a molecular biological resolution of the monophyly of Metazoa. Molecules of the extracellular matrix/basal lamina, with the integrin receptor, fibronec…
The role of mucin 1 in respiratory diseases
2020
Recent evidence has demonstrated that mucin 1 (MUC1) is involved in many pathological processes that occur in the lung. MUC1 is a transmembrane protein mainly expressed by epithelial and hematopoietic cells. It has a receptor-like structure, which can sense the external environment and activate intracellular signal transduction pathways through its cytoplasmic domain. The extracellular domain of MUC1 can be released to the external environment, thus acting as a decoy barrier to mucosal pathogens, as well as serving as a serum biomarker for the diagnosis and prognosis of several respiratory diseases such as lung cancer and interstitial lung diseases. Furthermore, bioactivated MUC1-cytoplasmi…
Chemogenetic Suppression of the Subthalamic Nucleus Induces Attentional Deficits and Impulsive Action in a Five-Choice Serial Reaction Time Task in M…
2020
The subthalamic nucleus (STN), a key component of the basal ganglia circuitry, receives inputs from broad cerebral cortical areas and relays cortical activity to subcortical structures. Recent human and animal studies have suggested that executive function, which is assumed to consist of a set of different cognitive processes for controlling behavior, depends on precise information processing between the cerebral cortex and subcortical structures, leading to the idea that the STN contains neurons that transmit the information required for cognitive processing through their activity, and is involved in such cognitive control directly and dynamically. On the other hand, the STN activity also …
The unique skeleton of siliceous sponges (Porifera; Hexactinellida and Demospongiae) that evolved first from the Urmetazoa during the Proterozoic: a …
2007
Abstract. Sponges (phylum Porifera) had been considered as an enigmatic phylum, prior to the analysis of their genetic repertoire/tool kit. Already with the isolation of the first adhesion molecule, galectin, it became clear that the sequences of the sponge cell surface receptors and those of the molecules forming the intracellular signal transduction pathways, triggered by them, share high similarity to those identified in other metazoan phyla. These studies demonstrated that all metazoan phyla, including the Porifera, originate from one common ancestor, the Urmetazoa. The sponges evolved during a time prior to the Ediacaran-Cambrian boundary (542 million years ago (myr)). They appeared du…