Refine
Is part of the Bibliography
- yes (79)
Year of publication
Document Type
- Doctoral Thesis (49)
- Journal article (30)
Keywords
- Thrombozyt (12)
- platelets (9)
- VASP (7)
- LASP-1 (6)
- Vasodilatator-stimuliertes Phosphoprotein (6)
- Thrombozyten (4)
- endothelial cells (4)
- phosphorylation (4)
- Brustkrebs (3)
- Clopidogrel (3)
- LASP1 (3)
- Maus (3)
- Phosphorylierung (3)
- Signaltransduktion (3)
- actin cytoskeleton (3)
- platelet (3)
- Blutgerinnung (2)
- Blutstillung (2)
- Cyclo-AMP (2)
- Cyclo-GMP (2)
- Cyclo-GMP-Derivate (2)
- Cyclonucleotide (2)
- Endothel (2)
- Endothelzelle (2)
- Endothelzellen (2)
- Genexpression (2)
- Haemostasis (2)
- Kongestive Herzmuskelkrankheit (2)
- Medulloblastom (2)
- Medulloblastoma (2)
- Megakaryozyten (2)
- Molekulargenetik (2)
- NET (2)
- PRRT (2)
- Spred (2)
- Spred Protein (2)
- Stickstoffmonoxid (2)
- Zelladhäsion (2)
- Zellskelett (2)
- aorta (2)
- apoptosis (2)
- atherosclerosis (2)
- cell adhesion (2)
- cell staining (2)
- clopidogrel (2)
- diet (2)
- flow cytometry (2)
- inflammation (2)
- macrophages (2)
- 5-> (1)
- 5C6 (1)
- ADP receptors (1)
- ADP-Rezeptoren (1)
- AMPK (1)
- Actin (1)
- Actin-Polymerisation (1)
- Actin-bindende Proteine (1)
- Adenylatcyclase (1)
- Adenylylcyclase (1)
- Aktin Zytoskelett (1)
- Aktin-Zytoskelett (1)
- Aktivierung (1)
- Angiogenese (1)
- Antigen CD41 (1)
- Apple Domäne (1)
- Apple domain (1)
- Arginine (1)
- Arteriosklerose (1)
- Atherosklerose (1)
- BCR-ABL (1)
- BMP (1)
- BMP-2 (1)
- Blutgefäß (1)
- Bradykinin (1)
- C-terminal-Src-Kinase (1)
- CCM3 (1)
- CHO cell (1)
- CHO-Zelle (1)
- CML (1)
- CRKL (1)
- Cell permeability (1)
- Chronische Herzinsuffizienz (1)
- Cortical Actin Cytoskeleton (1)
- Cyclic nucleotides (1)
- Cyclisches Nucleotid Phosphodiesterase <3 (1)
- DAPI staining (1)
- DCM (1)
- DLD (1)
- DNA double-strand breaks (1)
- Denaturing high-performance liquid chromatography (1)
- Dendritische Zelle (1)
- Desmoplakin (1)
- Diabetes mellitus (1)
- Dihydrolipoamid-Dehydrogenase (1)
- Dipyridamol (1)
- Dissoziationskonstante (1)
- Domäne <Biochemie> (1)
- Drosophila (1)
- Durchflußzytometrie (1)
- EDS (1)
- ERK signaling cascade (1)
- ES-Cells (1)
- EVH-1 (1)
- EVH1 Domäne (1)
- EVH1 domain (1)
- EVH1 domains (1)
- Ehlers-Danlos syndrome (1)
- Eierstockkrebs (1)
- Endothelial Cell-Cell Contacts (1)
- Endotheliale Zell-Zell-Kontakte (1)
- Enzyme immunoassay (1)
- Enzymkinetik (1)
- Epac (1)
- Erbkrankheit (1)
- Ewing-Sarkom (1)
- Extrazelluläre Matrix (1)
- FGF19 (1)
- FRET (1)
- FXI (1)
- FXR (1)
- Faktor V Leiden (1)
- Familiäre dilatative Kardiomyopathie (1)
- Fibroblastenwachstumsfaktor (1)
- Fibrose (1)
- Fluoreszenz-Resonanz-Energie-Transfer (1)
- GAF Domaine (1)
- Gaf domaine (1)
- Gehirn (1)
- Genanalyse (1)
- Genmutation (1)
- Genommutation (1)
- Gerinnungsfaktor XI (1)
- Gerinnungsfaktor XII (1)
- Gerinnungsfaktoren (1)
- Gerinnungsfaktoren in Thrombozytenkonzentraten (1)
- Group B streptococcus (1)
- Harnblasenkarzinom (1)
- Herzinsuffizienz (1)
- Herzkrankheit (1)
- Herzmuskelerkrankung (1)
- Herzmuskelkrankheit (1)
- Hoher Faktor XI (1)
- Hydrolyse (1)
- Hyperkalaemia (1)
- Hämostase (1)
- Immunoblot (1)
- Inhibition (1)
- Inosite (1)
- Insulin (1)
- Insulinrezeptor (1)
- Integrin alphaIIb-beta3 (1)
- Juvenile biventricular cardiomyopathy (1)
- Kallikrein-Kinin-System (1)
- Kallikreine (1)
- Kardiomyopathie (1)
- Kern-Zytosoltranslokation (1)
- Ki67 (1)
- Kind / Onkologie (1)
- Kinin (1)
- Knockout <Molekulargenetik> (1)
- Knockout Mäuse (1)
- Kontaktphasensystem (1)
- Krankheitsgen (1)
- LASP-2 (1)
- LASP1 (LIM and SH3 Protein 1) (1)
- LASP1 (LIM und SH3 Protein 1) (1)
- LNCaP (1)
- Lamellipodium (1)
- Laminopathie (1)
- Laminopathy (1)
- Linear Mixed Inhibition (1)
- Linear mixed inhibition (1)
- Lipidomics (1)
- Lipophilicity (1)
- Lysine (1)
- MAG3 (1)
- MAP Kinase (1)
- MAP kinase (1)
- MAPK (1)
- MMP (1)
- MMP (Matrix-Metalloproteasen) (1)
- MMP (Matrix-Metalloproteases) (1)
- Mammakarzinom (1)
- Matrix-Metalloproteasen (1)
- Matrixmetalloproteinase (1)
- Medaka (1)
- Medizin (1)
- Megakaryocytes (1)
- Megakaryozyt (1)
- Metabolism (1)
- Metabolismus (1)
- Metalloproteasen (1)
- Mikrokalorimetrie (1)
- Missbildung (1)
- Mitochondriopathie (1)
- Mitochondriopathy (1)
- Mutation (1)
- Myc (1)
- NIR3 (1)
- NO (1)
- NONO (1)
- Neutrophile (1)
- Nucleotide (1)
- Ovarkarzinom (1)
- PDEF (1)
- PITPnm2 (1)
- PKA (1)
- PKB (1)
- PKG (1)
- PSA (1)
- Palmoplantar keratoderma (1)
- Phosphatidylinositol Transfer Proteine (1)
- Plakophilin-2 (1)
- Plasmakallikrein (1)
- Plasmakonzentrate (1)
- Platelets (1)
- Platets (1)
- Pluripotency (1)
- Plättchen (1)
- Plättchenaktivierung (1)
- Plättchenhemmung (1)
- Polymorphismus (1)
- Polyphosphate (1)
- Proliferation (1)
- Prostaglandine (1)
- Prostanoid-Rezeptor (1)
- Prostanoide (1)
- Protamin (1)
- Protamine (1)
- Protein interactions (1)
- Proteine (1)
- Proteinkinase A (1)
- Proteinkinase B (1)
- Proteinkinase G (1)
- Proteinphosphorylierung (1)
- Punktmutation (1)
- Purinorezeptor (1)
- RAR (1)
- RNS-Interferenz (1)
- RNS-Spleißen (1)
- ROS (1)
- RXR (1)
- Reaktive Sauerstoffspezies (1)
- Regulation (1)
- Restriktive Herzmuskelkrankheit (1)
- Rezeptor (1)
- Rezeptorregulation (1)
- SNP (1)
- STAT3 (1)
- Sekretion (1)
- Seque (1)
- Sequenzierung (1)
- Skleroproteine (1)
- Spectrin (1)
- Spektrin (1)
- Spleißvarianten (1)
- Spred protein (1)
- Src-Proteine (1)
- Stammzellen (1)
- Staphylococcus aureus (1)
- Stickst (1)
- Streptococcus (1)
- T cells (1)
- TRIP6 (1)
- Therapiekontrolle (1)
- Therapieresistenz (1)
- Thrombin (1)
- Thrombingenerierung (1)
- Thrombocytes (1)
- Thrombose (1)
- Thrombosis (1)
- Thrombozytenkonzentrate (1)
- Transkriptionsfaktor (1)
- Troponin I (1)
- Tumorzelle (1)
- Urothelkarzinom (1)
- Variabilität (1)
- Vasodilatatoren (1)
- Vasodilator-stimulated phosphoprotein (1)
- Vitamin A (1)
- Willebrand-Jürgens-Syndrom (1)
- Wirkmechanismus (1)
- ZO-2 (1)
- Zelldifferenzierung (1)
- Zellkern (1)
- Zwergenwuchs (1)
- Zyxin (1)
- abdominal aortic-aneurysm (1)
- aberrant transcripts (1)
- amino acids (1)
- angiogenesis (1)
- atherosclerotic vascular disease (1)
- autotoxicity (1)
- beta-aminopropionitrile (1)
- biomarker (1)
- bladder cancer (1)
- brain tumor (1)
- breast cancer (1)
- breast cancer cells (1)
- cAMP (1)
- cDNA arrays (1)
- cDNA-Arrays (1)
- cGMP (1)
- cPLA2 (1)
- calcium signaling (1)
- camp signaling pathway (1)
- cancer (1)
- cancer cells (1)
- cancer treatment (1)
- cardiomyopathy (1)
- cell differentiation (1)
- cell membranes (1)
- cerebral small vessel disease (1)
- colorectal cancer (1)
- contact activation system (1)
- csk (1)
- curative resection (1)
- cyclic nucleotides (1)
- cytotoxic T cells (1)
- dependent protein-kinase (1)
- differentiation (1)
- dilation (1)
- dipyridamole (1)
- discrete (1)
- drug-monitoring (1)
- dwarfism (1)
- early onset sepsis (1)
- endothelium (1)
- epithelial cells (1)
- erythrocytes (1)
- factor V Leiden (1)
- factor binding profiles (1)
- familial dilated cardiomyopathy (1)
- fibrosis (1)
- gene expression (1)
- gene targeting (1)
- genetisch bedingte Krankheit (1)
- genome integrity (1)
- haert muscle disease (1)
- heart (1)
- heat shock response (1)
- hematopoietic stem cells (1)
- hemoglobin (1)
- hepatic resection (1)
- high factor XI (1)
- histology (1)
- human osteosarcoma xenografts (1)
- humans (1)
- hypercholesterolemia (1)
- hyperkalemia (1)
- hypoxia inducible factor 1 (1)
- hämatopoetische Stammzellen (1)
- immunity (1)
- immunotherapy (1)
- infection (1)
- innate immunity (1)
- integrin alphaIIb-beta3 (1)
- integrins (1)
- intracellular receptors (1)
- intrinsic coagulation cascade (1)
- intrinsische Gerinnungskaskade (1)
- invadopodia (1)
- ischaemic heart disease (1)
- isothiocyanates (1)
- kidney function (1)
- kinin (1)
- knock-out (1)
- knockout (1)
- knockout mice (1)
- lamellipodium (1)
- lipidomics (1)
- lung resection (1)
- lymphocytes (1)
- mammary carcinoma (1)
- megakaryocytes (1)
- melanin (1)
- melanocytes (1)
- melanoma cells (1)
- melanomas (1)
- membrane proteins (1)
- metastasis (1)
- miRNA 17-92 Cluster (1)
- miRNS (1)
- microRNA (1)
- microdomains (1)
- mir-203 (1)
- monocyte subset (1)
- monocytes (1)
- mouse (1)
- mouse model (1)
- mouse models (1)
- mustard oil bomb (1)
- mutation (1)
- myocardial infarction (1)
- myocarditis (1)
- nardilysin (1)
- neovascularization, physiologic (1)
- neutrophils (1)
- nilotinib (1)
- nitric oxide (1)
- nuclear cytosolic translocation (1)
- nucleo-cytoplasmic (1)
- nutritional deficiencies (1)
- open-access database (1)
- ovarian carcinoma (1)
- p38 MAP kinase (1)
- p53 (1)
- pancreatic cancer (1)
- pathogenic bacteria (1)
- peripheral artery occlusive disease (1)
- phosphatidylinsoitol transfer protein (1)
- plakophilin 2 (1)
- plasma kallikrein (1)
- platelet activation (1)
- platelet aggregation (1)
- platelet dysfunction (1)
- polystyrene (1)
- prediction (1)
- proliferation (1)
- prostanoid receptor (1)
- prostanoids (1)
- prostate cancer (1)
- protein phosphorylation (1)
- pädiatrische Onkologie (1)
- r760c (1)
- r854q (1)
- reactive electrophilic species (1)
- receptor-regulation (1)
- redox homeostasis (1)
- regulatory T cells (1)
- repair and replication (1)
- rupture (1)
- sequencing (1)
- signal transduction (1)
- smooth muscle cells (1)
- solid tumors (1)
- soluble guanylate cyclase (1)
- spleen (1)
- splice variant (1)
- src kinase (1)
- streptococci (1)
- sulforaphane (1)
- surgical oncology (1)
- surgical resection (1)
- t-lymphocytes (1)
- teeth (1)
- therapy non-responder (1)
- thrombin generation (1)
- thrombosis (1)
- tooth eruption (1)
- transcapillary pressure gradient (1)
- transcription factor SPT5 (1)
- transfection (1)
- transitional cell carcinoma (1)
- troponin I (1)
- tumor growth (1)
- tumor microenvironment (1)
- tumor-infiltrating (1)
- tyrosine (1)
- variability (1)
- vascular normalization (1)
- vascular type (1)
- vasodilator-stimulated phosphoprotein (1)
- vasodilators (1)
- vesicles (1)
- vitamin D (1)
- von-willebrand-syndrom (1)
- von-willebrand-syndrome (1)
- xenopus oocytes (1)
- y1146c (1)
- Überexpression (1)
- Überleben (1)
Institute
- Institut für Klinische Biochemie und Pathobiochemie (79) (remove)
Tumors are characterized by a rigid, highly cross-linked extracellular matrix (ECM), which impedes homogeneous drug distribution and potentially protects malignant cells from exposure to therapeutics. Lysyl oxidases are major contributors to tissue stiffness and the elevated expression of these enzymes observed in most cancers might influence drug distribution and efficacy. We examined the effect of lysyl oxidases on drug distribution and efficacy in 3D in vitro assay systems. In our experiments elevated lysyl oxidase activity was responsible for reduced drug diffusion under hypoxic conditions and consequently impaired cytotoxicity of various chemotherapeutics. This effect was only observed in 3D settings but not in 2D-cell culture, confirming that lysyl oxidases affect drug efficacy by modification of the ECM and do not confer a direct desensitizing effect. Both drug diffusion and efficacy were strongly enhanced by inhibition of lysyl oxidases. The results from the in vitro experiments correlated with tumor drug distribution in vivo, and predicted response to therapeutics in murine tumor models. Our results demonstrate that lysyl oxidase activity modulates the physical barrier function of ECM for small molecule drugs influencing their therapeutic efficacy. Targeting this process has the potential to significantly enhance therapeutic efficacy in the treatment of malignant diseases.
Atherosklerose ist eine chronisch-entzündliche Gefäßerkrankung. Dabei sind alle entscheidenden Zellen des angeborenen und adaptiven Immunsystems involviert. Besonders dendritische Zellen (DCs) expandieren subendothelial während der Progression einer Atherosklerose. Diese können Antigene aufnehmen und daraufhin Zytokine produzieren oder andere Immunzellen aktivieren. MicroRNAs (miRNAs) sind kleine nicht-kodierende Stränge aus Ribonukleinsäure, welche als weitere Ebene der Genregulation wichtige Zellvorgänge beeinflussen können. Diese Arbeit zeigt mögliche Zielproteine des miRNA 17-92 Clusters in dendritischen Zellen auf und schlägt mögliche Modelle vor, wie dadurch Zellvorgänge von DCs in der Atherosklerose reguliert werden könnten.
Background
Peptide receptor radionuclide therapy (PRRT) is applied in patients with advanced neuroendocrine tumors. Co-infused amino acids (AA) should prevent nephrotoxicity. The aims of this study were to correlate the incidence of AA-induced hyperkalemia (HK) (≥5.0 mmol/l) and to identify predictors of AA-induced severe HK (>6.0).
Methods
In 38 patients, standard activity of \(^{177}Lu\)-labelled somatostatin analogs was administered. Pre-therapeutic kidney function was assessed by renal scintigraphy and laboratory tests. For kidney protection, AA was co-infused. Biochemical parameters (potassium, glomerular filtration rate, creatinine, blood urea nitrogen (BUN), sodium, phosphate, chloride, and lactate dehydrogenase (LDH)) were obtained prior to 4 and 24 h after the AA infusion. Incidence of HK (≥5.0) was correlated with pre-therapeutic kidney function and serum parameters. Formulas for the prediction of severe hyperkalemia (>6.0) were computed and prospectively validated.
Results
At 4 h, HK (≥5.0) was present in 94.7% with severe HK (>6.0) in 36.1%. Values normalized after 24 h in 84.2%. Pre-therapeutic kidney function did not correlate with the incidence of severe HK.
Increases in K+ were significantly correlated with decreases in phosphate (r = −0.444, p < 0.005) and increases in BUN (r = 0.313, p = 0.056). A baseline BUN of >28 mg/dl had a sensitivity of 84.6% and a specificity of 60.0% (AUC = 0.75) in predicting severe HK of >6.0 (phosphate, AUC = 0.37).
Computing of five standard serum parameters (potassium, BUN, sodium, phosphate, LDH) resulted in a sensitivity of 88.9% and a specificity of 79.3% for the prediction of severe HK >6.0 (accuracy = 81.6%).
Conclusions
A combination of serum parameters predicted prospectively the occurrence of relevant HK with an accuracy of 81.6% underlining its potential utility for identifying ‘high-risk’ patients prone to PRRT.
Distinct functions of specialized dendritic cell subsets in atherosclerosis and the road ahead
(2014)
Atherosclerotic vascular disease is modulated by immune mechanisms. Dendritic cells (DCs) and T cells are present within atherosclerotic lesions and function as central players in the initiation and modulation of adaptive immune responses. In previous years, we have studied the functional contribution of distinct DC subsets in disease development, namely, that of CCL17-expressing DCs as well as that of plasmacytoid DCs that play specialized roles in disease development. This review focuses on important findings gathered in these studies and dissects the multifaceted contribution of CCL17-expressing DCs and pDCs to the pathogenesis of atherosclerosis. Furthermore, an outlook on future challenges faced when studying DCs in this detrimental disease are provided, and hurdles that will need to be overcome in order to enable a better understanding of the contribution of DCs to atherogenesis are discussed, a prerequisite for their therapeutic targeting in atherosclerosis.
Dendritic cells (DCs) can be sub-divided into various subsets that play specialized roles in priming of adaptive immune responses. Atherosclerosis is regarded as a chronic inflammatory disease of the vessel wall and DCs can be found in non-inflamed and diseased arteries. We here performed a systematic analyses of DCs subsets during atherogenesis. Our data indicate that distinct DC subsets can be localized in the vessel wall. In C57BL/6 and low density lipoprotein receptor-deficient (Ldlr−/−) mice, CD11c+ MHCII+ DCs could be discriminated into CD103− CD11b+F4/80+, CD11b+F4/80− and CD11b−F4/80− DCs and CD103+ CD11b−F4/80− DCs. Except for CD103− CD11b− F4/80− DCs, these subsets expanded in high fat diet-fed Ldlr−/− mice. Signal-regulatory protein (Sirp)-α was detected on aortic macrophages, CD11b+ DCs, and partially on CD103− CD11b− F4/80− but not on CD103+ DCs. Notably, in FMS-like tyrosine kinase 3-ligand-deficient (Flt3l−/−) mice, a specific loss of CD103+ DCs but also CD103− CD11b+ F4/80− DCs was evidenced. Aortic CD103+ and CD11b+ F4/80− CD103− DCs may thus belong to conventional rather than monocyte-derived DCs, given their dependence on Flt3L-signalling. CD64, postulated to distinguish macrophages from DCs, could not be detected on DC subsets under physiological conditions, but appeared in a fraction of CD103− CD11b+ F4/80− and CD11b+ F4/80+ cells in atherosclerotic Ldlr−/− mice. The emergence of CD64 expression in atherosclerosis may indicate that CD11b+ F4/80− DCs similar to CD11b+ F4/80+ DCs are at least in part derived from immigrated monocytes during atherosclerotic lesion formation. Our data advance our knowledge about the presence of distinct DC subsets and their accumulation characteristics in atherosclerosis, and may help to assist in future studies aiming at specific DC-based therapeutic strategies for the treatment of chronic vascular inflammation.
Several studies have linked overexpression of the LIM and SH3 domain protein 1 (LASP1) to progression of breast, colon, liver, and bladder cancer. However, its expression pattern and role in human prostate cancer (PCa) remained largely undefined.
Analysis of published microarray data revealed a significant overexpression of LASP1 in PCa metastases compared to parental primary tumors and normal prostate epithelial cells. Subsequent gene-set enrichment analysis comparing LASP1-high and -low PCa identified an association of LASP1 with genes involved in locomotory behavior and chemokine signaling. These bioinformatic predictions were confirmed in vitro as the inducible short hairpin RNA-mediated LASP1 knockdown impaired migration and proliferation in LNCaP prostate cancer cells.
By immunohistochemical staining and semi-quantitative image analysis of whole tissue sections we found an enhanced expression of LASP1 in primary PCa and lymph node metastases over benign prostatic hyperplasia. Strong cytosolic and nuclear LASP1 immunoreactivity correlated with PSA progression. Conversely, qRT-PCR analyses for mir-203, which is a known translational suppressor of LASP1 in matched RNA samples revealed an inverse correlation of LASP1 protein and mir-203 expression. Collectively, our results suggest that loss of mir-203 expression and thus uncontrolled LASP1 overexpression might drive progression of PCa.
Chronic myeloid leukemia (CML) is characterized by a genomic translocation generating a permanently active BCR-ABL oncogene with a complex pattern of atypically tyrosine-phosphorylated proteins that drive the malignant phenotype of CML. Recently, the LIM and SH3 domain protein 1 (LASP1) was identified as a component of a six gene signature that is strongly predictive for disease progression and relapse in CML patients. However, the underlying mechanisms why LASP1 expression correlates with dismal outcome remained unresolved.
Here, we identified LASP1 as a novel and overexpressed direct substrate of BCR-ABL in CML. We demonstrate that LASP1 is specifically phosphorylated by BCR-ABL at tyrosine-171 in CML patients, which is abolished by tyrosine kinase inhibitor therapy. Further studies revealed that LASP1 phosphorylation results in an association with CRKL - another specific BCR-ABL substrate and bona fide biomarker for BCR-ABL activity. pLASP1-Y171 binds to non-phosphorylated CRKL at its SH2 domain. Accordingly, the BCR-ABL-mediated pathophysiological hyper-phosphorylation of LASP1 in CML disrupts normal regulation of CRKL and LASP1, which likely has implications on downstream BCR-ABL signaling. Collectively, our results suggest that LASP1 phosphorylation might serve as an additional candidate biomarker for assessment of BCR-ABL activity and provide a first step toward a molecular understanding of LASP1 function in CML.
von Willebrand factor/ristocetin (vWF/R) induces GPIb-dependent platelet agglutination and activation of αIIbβ3 integrin, which also binds vWF. These conditions make it difficult to investigate GPIb-specific signaling pathways in washed platelets. Here, we investigated the specific mechanisms of GPIb signaling using echicetin-coated polystyrene beads, which specifically activate GPIb. We compared platelet activation induced by echicetin beads to vWF/R. Human platelets were stimulated with polystyrene beads coated with increasing amounts of echicetin and platelet activation by echicetin beads was then investigated to reveal GPIb specific signaling. Echicetin beads induced αIIbβ3-dependent aggregation of washed platelets, while under the same conditions vWF/R treatment led only to αIIbβ3-independent platelet agglutination. The average distance between the echicetin molecules on the polystyrene beads must be less than 7 nm for full platelet activation, while the total amount of echicetin used for activation is not critical. Echicetin beads induced strong phosphorylation of several proteins including p38, ERK and PKB. Synergistic signaling via P2Y12 and thromboxane receptor through secreted ADP and TxA2, respectively, were important for echicetin bead triggered platelet activation. Activation of PKG by the NO/sGC/cGMP pathway inhibited echicetin bead-induced platelet aggregation. Echicetin-coated beads are powerful and reliable tools to study signaling in human platelets activated solely via GPIb and GPIb-triggered pathways.
T cell activation represents a double-edged sword in atherogenesis, as it promotes both pro-inflammatory T cell activation and atheroprotective Foxp3(+) regulatory T cell (Treg) responses. Here, we investigated the role of the co-inhibitory receptor programmed cell death-1 (PD-1) in T cell activation and CD4(+) T cell polarization towards pro-atherogenic or atheroprotective responses in mice. Mice deficient for both low density lipoprotein receptor and PD-1 (Ldlr(-/-)Pd1(-/-)) displayed striking increases in systemic CD4(+) and CD8(+) T cell activation after 9 weeks of high fat diet feeding, associated with an expansion of both pro-atherogenic IFNγ-secreting T helper 1 cells and atheroprotective Foxp3+ Tregs. Importantly, PD-1 deficiency did not affect Treg suppressive function in vitro. Notably, PD-1 deficiency exacerbated atherosclerotic lesion growth and entailed a massive infiltration of T cells in atherosclerotic lesions. In addition, aggravated hypercholesterolemia was observed in Ldlr(-/-)Pd1(-/-) mice. In conclusion, we here demonstrate that although disruption of PD-1 signaling enhances both pro- and anti-atherogenic T cell responses in Ldlr(-/-) mice, pro-inflammatory T cell activation prevails and enhances dyslipidemia, vascular inflammation and atherosclerosis.
Introduction: The aim of our study was to develop a reproducible murine model of elastase-induced aneurysm formation combined with aortic transplantation.
Methods: Adult male mice (n = 6-9 per group) underwent infrarenal, orthotopic transplantation of the aorta treated with elastase or left untreated. Subsequently, both groups of mice were monitored by ultrasound until 7 weeks after grafting.
Results: Mice receiving an elastase-pretreated aorta developed aneurysms and exhibited a significantly increased diastolic vessel diameter compared to control grafted mice at 7 week after surgery (1.11 +/- 0.10 mm vs. 0.75 +/- 0.03 mm; p <= 0.001). Histopathological examination revealed disruption of medial elastin, an increase in collagen content and smooth muscle cells, and neointima formation in aneurysm grafts.
Conclusions: We developed a reproducible murine model of elastase-induced aneurysm combined with aortic transplantation. This model may be suitable to investigate aneurysm-specific inflammatory processes and for use in gene-targeted animals.
Background
Peptide receptor radionuclide therapy (PRRT) is routinely used for advanced or metastasized neuroendocrine tumours (NET). To prevent nephrotoxicity, positively charged amino acids (AA) are co-infused. The aim of this study was to correlate the risk for therapy-related hyperkalaemia with the total amount of AA infused.
Methods
Twenty-two patients undergoing PRRT with standard activities of 177Lu-DOTATATE/-TOC were monitored during two following treatment cycles with co-infusion of 75 and 50 g of AA (L-arginine and L-lysine), respectively. Mean serum levels of potassium and other parameters (glomerular filtration rate [GFR], creatinine, blood urea nitrogen [BUN], phosphate, chloride, lactate dehydrogenase) prior to, 4 h and 24 h after AA infusion were compared.
Results
Self-limiting hyperkalaemia (>5.0 mmol/l) resolving after 24 h occurred in 91% (20/22) of patients in both protocols. Potassium levels, BUN, creatinine, GFR, phosphate, chloride and LDH showed a similar range at 4 h after co-infusion of 75 or 50 g of AA, respectively (p > 0.05). Only GFR and creatinine levels at 24 h varied significantly between the two co-infusion protocols (p < 0.05).
Conclusions
Hyperkalaemia is a frequent side effect of AA infusion in PRRT. Varying the dose of co-infused amino acids did not impact on the incidence and severity of hyperkalaemia.
Die vorliegende Arbeit untersuchte die Veränderungen der wichtigsten hämostatischen Komponenten der plasmatischen Gerinnung in Thrombozyten- und Plasmakonzentraten während der achttägigen Lagerung bei Raumtemperatur. Es wurden keine signifikanten und klinisch relevanten Veränderungen der plasmatischen hämostatischen Kapazität des Plasmas für Fibrinogen, Gerinnungsfaktor XI, XII und XIII, Protein S und C (quantitative Messung), D-Dimere, von Willebrand-Faktor, Kollagenbindungs-aktivität und Ristocetin-Cofaktor nachgewiesen. Es kam jedoch zu einer zeitabhängigen Veränderung während der Lagerung bei PTT, Quick, Thrombinzeit, Gerinnungsfaktoren II, V, VII, VIII, IX, und X, Antithrombin III, Protein S und C (funktionelle Messung), Prothrombinfragmente F1+F2 und APC-Resistenz. Diese Veränderungen fanden sich zudem insbesondere in den gelagerten Thrombozytenkonzentraten. Die wenigen, in der Literatur verfügbaren Untersuchungen zeigen Ergebnisse, die den unseren vergleichbar sind. Erstmal wurden mit dieser Dissertationsarbeit jedoch umfassend alle diese Parameter in einem Ansatz verglichen. Vorausgesetzt, dass hämostaseologische Faktoren auch unter ungünstigen Lagerungsbedingungen weitgehend ihre hämostatische Kapazität behalten, kann bei Infusionen von Früh- oder Neugeborenen praktische Bedeutung erlangen, da die plasmatische hämostatische Kapazität in Thrombozytenkonzentraten nun in den Gesamtbedarf einbezogen werden kann. Ebenso können vereinfachte Lagerbedingungen (Raumtemperatur versus Tiefkühlung) in Krisensituationen enorme logistische Vorteile mit sich bringen. Weitere, insbesondere klinische Transfusionsstudien müssen nun zeigen, ob die ex vivo gewonnenen Erkenntnisse zur Haltbarkeit hämostatischer Gerinnungsfaktoren sich in den klinisch-praktischen Einsatz übertragen lassen. Mit unseren Versuchen wollten wir auch dazu beitragen, zukünftig möglichst schnelle und praktikable Therapievorschläge für Notfälle bereitzustellen. Eine bedeutende Rolle kann das bei Raumtemperatur gelagerten Plasma in der Transfusionsmedizin, Notfallmedizin, bei Operationen und in Kriseneinsätzen spielen. Es bleiben noch viele Fragen zu diesem Thema offen. Diese Arbeit wird zu weiterer Forschung anregen.
p38 Mitogen-activated protein (MAP) kinase is involved in the apoptosis of nucleated cells. Although platelets are anucleated cells, apoptotic proteins have been shown to regulate platelet lifespan. However, the involvement of p38 MAP kinase in platelet apoptosis is not yet clearly defined. Therefore, we investigated the role of p38 MAP kinase in apoptosis induced by a mimetic of BH3-only proteins, ABT-737, and in apoptosis-like events induced by such strong platelet agonists as thrombin in combination with convulxin (Thr/Cvx), both of which result in p38 MAP kinase phosphorylation and activation. A p38 inhibitor (SB202190) inhibited the apoptotic events induced by ABT-737 but did not influence those induced by Thr/Cvx. The inhibitor also reduced the phosphorylation of cytosolic phospholipase \(A_2\) (cPLA2), an established p38 substrate, induced by ABT-737 or Thr/Cvx. ABT-737, but not Thr/Cvx, induced the caspase 3-dependent cleavage and inactivation of cPLA2. Thus, p38 MAPK promotes ABT-737-induced apoptosis by inhibiting the cPLA2/arachidonate pathway. We also show that arachidonic acid (AA) itself and in combination with Thr/Cvx or ABT-737 at low concentrations prevented apoptotic events, whereas at high concentrations it enhanced such events. Our data support the hypothesis that the p38 MAPK-triggered arachidonate pathway serves as a defense mechanism against apoptosis under physiological conditions.
LASP-1, das LIM und SH3 Protein 1, ist ein Aktin-bindendes Gerüstprotein, das in verschiedenen Tumorentitäten überexprimiert ist. Dabei scheint LASP-1 eine wichtig Rolle sowohl bei der Proliferation und Migration von Zellen als auch bei der Tumorgenese und Metastasierung zu spielen.
Ziel dieser Arbeit war es, die Expression von LASP-1 im Urothelkarzinom der Harnblase zu untersuchen und eine daraus abzuleitende klinische Relevanz für die Diagnostik zu evaluieren. Dazu wurden histologische Blasenschnitte immunhistochemisch nach LASP-1 gefärbt und Western Blot-Analysen von Urinproben durchgeführt.
Die Auswertung der immunhistochemisch gefärbten Blasenschnitte ergab, dass Urothelkarzinome signifikant mehr LASP-1 auf Proteinebene exprimieren als gesundes Blasengewebe. Allerdings konnte keine Korrelation zwischen der Stärke der LASP-1-Expression und verschiedener klinisch-pathologischer Parameter nachgewiesen werden.
Mittels Western Blot-Analysen gelang es, LASP-1 eindeutig im Urin und statistisch signifikant häufiger bei Blasenkarzinompatienten zu detektieren. Ohne Berücksichtigung einer Kontamination mit LASP-1-positiven Blut- und Entzündungszellen ist der LASP-1-Nachweis im Western Blot mit einer Gesamtsensitivität von 84,2% derzeit sensitiver als die meisten erhältlichen Tumormarker. Darüber hinaus ergab der Vergleich von Spontanurin und von Harnblasenspülflüssigkeit, dass Spontanurinproben sogar geeigneter zur Diagnostik zu sein scheinen.
Abschließend kann zusammengefasst werden, dass LASP-1 aufgrund der einfachen, nicht invasiven und kostengünstigen Probengewinnung zusammen mit den hohen Werten für Sensitivität und Spezifität als Urin-basierter Tumormarker für das Urothelkarzinom der Harnblase vielversprechend zu sein scheint.
LASP-1 (LIM und SH3 Domänen Protein) ist ein in Zellen ubiquitär vorkommendes Protein, welches in verschiedenen Tumorgeweben eine pathophysiologische Überexpression aufweist. Das Protein besitzt eine LIM Domäne, zwei Aktinbindungsregionen sowie eine SH3 Domäne und bindet einerseits an dynamischen Aktinstrukturen wie den fokalen Kontakten, Lamellopodien und Membranfortsätzen, kann andererseits aber auch in den Zellkern translokalisieren. Für Aktinstrukturen wirkt LASP-1 als Gerüstprotein und ist wichtig für die Migration und Proliferation der Zellen. Die Funktion von LASP-1 im Zellkern ist noch nicht bekannt, da aber in Tumorzellen eine erhöhte nukleare Akkumulation von LASP-1 beobachtet werden konnte, deren Intensität mit der Tumorgröße sowie dem Langzeitüberleben der Patientinnen korreliert, ist LASP-1, zusätzlich zu seiner Funktion als Strukturprotein, vermutlich auch ein Transkriptionsfaktor oder ein transkriptioneller Kofaktor. Eine Herunterregulation von LASP-1 in verschiedenen Tumorentitäten führt zur Inhibition der Proliferation und Migration. In dieser Arbeit konnte der bisher unbekannte Zellkernimport und -export von LASP-1 aufgeklärt werden. Maßgeblich daran beteiligt ist ein durch Pulldown Experimente neu identifizierter LASP-1 Bindungspartner: das Zonula Occludens 2 Protein (ZO-2). Mittels Immunpräzipitationen und Immunfluoreszenzen wurde diese Interaktion bestätigt. Nach Phosphorylierung von LASP-1 an Ser-146 durch Aktivierung der cAMP-abhängigen Proteinkinase (PKA) kommt es zu einer partiellen Ablösung des LASP-1/ZO-2 Komplexes aus den fokalen Kontakten hin zu einer vermehrten Kernlokalisation beider Proteine. Dies lässt sich durch Kern/Zytosol Trennungen belegen. Dabei ist die Bindung von LASP-1 an ZO-2 essentiell für die Translokation in den Zellkern, da bei einem ZO-2 Knockdown auch nach PKA Aktivierung LASP-1 zytosolisch lokalisiert bleibt. Wie Mutationsanalysen zeigen, findet die Interaktion zwischen der C-terminalen SH3 Domäne im LASP-1 und der Prolin-reichen SH3-Bindungssequenz im Bereich der Aminosäuren 1103-1121 am C-Terminus im ZO-2 statt. Die Translokation des Komplexes in den Kern erfolgt dabei über das Kernlokalisationssignal im ZO-2, da die LASP-1 Sequenz selbst keine nukleare Importsequenz aufweist. Im Zellkern konnte die direkte Interaktion von LASP-1 und ZO-2 mittels Duolink® Proximity Ligation Assay sichtbar gemacht werden. Der Export der Proteine erfolgt über das Protein CRM1. Eine Inhibition der Kernexportmaschinerie mit Leptomycin B erhöht die Konzentration beider Proteine im Zellkern. Das nukleare Exportsignal (NES) im LASP-1 konnte durch Punktmutationen N-terminal der Leucin-reichen Aminosäuresequenz 70-77 zugeordnet werden (NLRLKQQS). Im letzten Schritt dieses Zyklus erfolgt die Relokalisation von LASP-1 zurück an die Zellmembranstrukturen. Der neu gefundene Signalweg dient wahrscheinlich zur Weiterleitung von externen Stimuli in den Kern und zur Genregulation - mit LASP-1 als Transkriptionsfaktor oder transkriptionellen Kofaktor.
Prostanoide wirken über Prostanoid-Rezeptoren auf die Aktivierung oder Hemmung der Thrombozyten. In dieser Arbeit wurde die Existenz und Funktionsweise der Prostanoid-Rezeptoren anhand synthetischer Agonisten und Antagonisten in humanen Thrombozyten nachgewiesen. Weiter wurde untersucht, über welche Prostanoid-Rezeptoren die Signaltransduktion der natürlichen Agonisten wie PGE2, PGE1 und PGA1 vermittelt wird, sowie das Zusammenspiel der Prostanoid-Rezeptoren auf die Aktivierung oder Hemmung der Thrombozyten gezeigt. Das Vorhandensein der Prostaglandin E2 Synthase 3 wurde nachgewiesen sowie erste Anhaltspunkte für die Existenz eines Komplexes aus Prostaglandin E2 Synthase 3, Hitzeschockprotein-90 sowie Casein Kinase 2 gezeigt.
Eukaryotic cells form a variety of adhesive structures to connect with their environment and to regulate cell motility. In contrast to classical focal adhesions, podosomes, highly dynamic structures of different cell types, are actively engaged in matrix remodelling and degradation. Podosomes are composed of an actin-rich core region surrounded by a ring-like structure containing signalling molecules, motor proteins as well as cytoskeleton-associated proteins. Lasp-1 is a ubiquitously expressed, actin-binding protein that is known to regulate cytoskeleton architecture and cell migration. This multidomain protein is predominantely present at focal adhesions, however, a second pool of Lasp-1 molecules is also found at lamellipodia and vesicle-like microdomains in the cytosol. In this report, we show that Lasp-1 is a novel component and regulator of podosomes. Immunofluorescence studies reveal a localization of Lasp-1 in the podosome ring structure, where it colocalizes with zyxin and vinculin. Life cell imaging experiments demonstrate that Lasp-1 is recruited in early steps of podosome assembly. A siRNA-mediated Lasp-1 knockdown in human macrophages affects podosome dynamics as well as their matrix degradation capacity. In summary, our data indicate that Lasp-1 is a novel component of podosomes and is involved in the regulation of podosomal function.
Gegenstand dieser Arbeit ist die Erstellung eines sogenannten "Targeting Vektors" zur gezielten Ausschaltung des Gens für Plasmakallikrein in der Maus, als Vorbereitung zur Schaffung einer Plasmakallikrein-defizienten Mauslinie. Plasmakallikrein ist eine im Blut zirkulierende Serinprotease, die Funktionen in Hämostase, Thrombusbildung und Fibrinolyse hat sowie sowohl direkt als auch indirekt mittels Bradykinin an Entzündungsvorgängen beteiligt ist. Zwei 5836 und 3834 bp lange Abschnitte aus dem murinen Plasmakallikrein-Gen wurden durch PCR isoliert und in ein Plasmid kloniert, das neben Resistenzgenen gegen Ampicillin und Neomycin auch das β-Galaktosidase-Gen zum Nachweis einer erfolgreichen Transfektion enthält. Der so entstandene "Targeting Vektor" hat eine Gesamtgröße von 18072 bp, die Basensequenz wurde durch Sequenzierung verifiziert. Der Vektor soll im Plasmakallikrein-Gen einen Teil der Exons 2 und 3 und damit einen Großteil des Signalpeptids und der ersten Proteindomäne funktionsunfähig machen. An den mit dieser Methode erstellten Knockout-Mäusen können die Funktionen von Plasmakallikrein genauer untersucht werden.
Immunoassays are routinely used as research tools to measure intracellular cAMP and cGMP concentrations. Ideally, this application requires antibodies with high sensitivity and specificity. The present work evaluates the cross-reactivity of commercially available cyclic nucleotide analogs with two non-radioactive and one radioactive cAMP and cGMP immunoassay. Most of the tested cyclic nucleotide analogs showed low degree competition with the antibodies; however, with Rp-cAMPS, 8-Br-cGMP and 8-pCPT-cGMP, a strong cross-reactivity with the corresponding cAMP and cGMP, respectively, immunoassays was observed. The determined EIA-binding constants enabled the measurement of the intracellular cyclic nucleotide concentrations and revealed a time- and lipophilicity-dependent cell membrane permeability of the compounds in the range of 10–30% of the extracellular applied concentration, thus allowing a more accurate prediction of the intracellular analog levels in a given experiment.
Two sons of a consanguineous marriage developed biventricular cardiomyopathy. One boy died of severe heart failure at the age of 6 years, the other was transplanted because of severe heart failure at the age of 10 years. In addition, focal palmoplantar keratoderma and woolly hair were apparent in both boys. As similar phenotypes have been described in Naxos disease and Carvajal syndrome, respectively, the genes for plakoglobin (JUP) and desmoplakin (DSP) were screened for mutations using direct genomic sequencing. A novel homozygous 2 bp deletion was identified in an alternatively spliced region of DSP. The deletion 5208_5209delAG led to a frameshift downstream of amino acid 1,736 with a premature truncation of the predominant cardiac isoform DSP-1. This novel homozygous truncating mutation in the isoform-1 specific region of the DSP C-terminus caused Carvajal syndrome comprising severe early-onset heart failure with features of non-compaction cardiomyopathy, woolly hair and an acantholytic form of palmoplantar keratoderma in our patient. Congenital hair abnormality and manifestation of the cutaneous phenotype in toddler age can help to identify children at risk for cardiac death.