Search results for "glycopeptides"
showing 10 items of 74 documents
Unique Microbial Catabolic Pathway for the Human Core N-Glycan Constituent Fucosyl-α-1,6-N-Acetylglucosamine-Asparagine
2020
The survival of commensal bacteria in the human gut partially depends on their ability to metabolize host-derived molecules. The use of the glycosidic moiety of N-glycoproteins by bacteria has been reported, but the role of N-glycopeptides or glycoamino acids as the substrates for bacterial growth has not been evaluated. We have identified in Lactobacillus casei strain BL23 a gene cluster (alf-2) involved in the catabolism of the glycoamino acid fucosyl-α-1,6-N-GlcNAc-Asn (6′FN-Asn), a constituent of the core-fucosylated structures of mammalian N-glycoproteins. The cluster consists of the genes alfHC, encoding a major facilitator superfamily (MFS) permease and the α-l-fucosidase AlfC, and t…
Preparation of Biomolecule Microstructures and Microarrays by Thiol-ene Photoimmobilization
2009
A mild, fast and flexible method for photoimmobilization of biomolecules based on the light-initiated thiol-ene reaction has been developed. After investigation and optimization of various surface materials, surface chemistries and reaction parameters, microstructures and microarrays of biotin, oligonucleotides, peptides, and MUC1 tandem repeat glycopeptides were prepared with this photoimmobilization method. Furthermore, MUC1 tandem repeat glycopeptide microarrays were successfully used to probe antibodies in mouse serum obtained from vaccinated mice. Dimensions of biomolecule microstructures were shown to be freely controllable through photolithographic techniques, and features down to 5 …
Synthetic (glyco-)peptides of the homophilic recognition domain of E-cadherin lead to increased E-cadherin mRNA synthesis and are inductors of cell d…
2010
E-cadherin is one of the critical molecules involved in the metastatic process in many types of cancer. Once combined, E-cadherin exceeds the amount of membranous E-cadherin on the cellular surface by activation of intracellular signaling cascades. Studies on transformed keratinocytes of the HaCat cell line showed induction of differentiation by synthetical partial structures of the homophilic binding region of E-cadherin. The knowledge of effects in lung cancer cells is sparse. Therefore, the effects in primary lung cancer cell lines were investigated. Four primary lung cancer cell lines were incubated for 3, 6, 12, 15, 18, and 24h with synthetic partial structures (peptide and glycopeptid…
Synthesis of glycopeptides and neoglycoproteins containing the fucosylated linkage region of N-glycoproteins.
1994
Abstract N-Glycoproteins fucosylated in the core region occur in tumor membranes and virus envelopes. Partial structures of such N-glycoproteins containing fucosylated chitobiosyl asparagine conjugates were synthesized using the allyloxycarbonyl (Aloc) and the tert-butyl ester protecting groups in the peptide portion. As the α-fucosidic bond of the conjugates revealed to be very sensitive to acids when carrying ether-type protecting groups, a method for exchanging the protecting groups of the fucose portion of saccharides was developed. Conjugates containing O-acetyl protected fucose proved to be stable against acids used in glycopeptide syntheses. These methods were applied in the synthesi…
Chemoenzymatic synthesis of O-glycopeptides carrying the tumor associated TN-antigen structure
1993
Abstract The application of the lipase-catalyzed C-terminal deprotection of heptyl esters for the construction of acid- and base-labile O -glycopeptides carrying the characteristic structural element of the tumor associated T N -antigen (GalNAc α→Ser/Thr) is described
Cardiovascular Mortality in Chest Pain Patients: Comparison of Natriuretic Peptides With Novel Biomarkers of Cardiovascular Stress.
2016
Natriuretic peptides are the standard biomarker for risk stratification in cardiovascular disease. Novel biomarkers of cardiovascular stress might allow refinement in risk stratification for patients with acute coronary syndrome (ACS). We tested the performance of these novel biomarkers for cardiovascular risk stratification in patients who presented with ACS.In the AtheroGene study, 873 patients presented with ACS in the emergency department. Biomarkers measured were: B-type natriuretic peptide (BNP), N-terminal pro BNP (NT-proBNP), midregional proatrial natriuretic peptide, midregional proadrenomedullin (MR-proADM), copeptin, and troponin I. The median follow-up time was 4 years and durin…
Amide-to-triazole switch vs. in vivo NEP-inhibition approaches to promote radiopeptide targeting of GRPR-positive tumors
2017
Abstract Introduction Radiolabeled bombesin (BBN)-analogs have been proposed for diagnosis and therapy of gastrin-releasing peptide receptor (GRPR)-expressing tumors, such as prostate, breast and lung cancer. Metabolic stability represents a crucial factor for the success of this approach by ensuring sufficient delivery of circulating radioligand to tumor sites. The amide-to-triazole switch on the backbone of DOTA-PEG 4 -[Nle 14 ]BBN(7–14) ( 1 ) was reported to improve the in vitro stability of resulting 177 Lu-radioligands. On the other hand, in-situ inhibition of neutral endopeptidase (NEP) by coinjection of phosphoramidon (PA) was shown to significantly improve the in vivo stability and …
Risk stratification of normotensive pulmonary embolism: prognostic impact of copeptin
2015
The prognostic value of copeptin, the C-terminal fragment of the precursor protein of vasopressin which is released upon stress, and hypotension in pulmonary embolism is unknown, especially if combined with biomarkers reflecting different pathophysiological axes such as myocardial injury (high-sensitivity troponin T (hsTnT)) and stretch (N-terminal pro-brain natriuretic peptide (NT-proBNP)).We prospectively studied 268 normotensive pulmonary embolism patients included in a single-centre cohort study.Patients with an adverse 30-day outcome (5.6%) had higher copeptin levels than patients with a favourable course (median (interquartile range) 51.8 (21.6–90.8) versus 13.2 (5.9–39.3) pmol·L−1; p…
Is high-sensitivity troponin, alone or in combination with copeptin, sensitive enough for ruling out NSTEMI in very early presenters at admission? A …
2019
Objectives: Copeptin and high-sensitivity cardiac troponin (HS-cTn) assays improve the early detection of non-ST-segment elevation myocardial infarction (NSTEMI). Their sensitivities may, however, be reduced in very early presenters.Setting: We performed a post hoc analysis of three prospective studies that included patients who presented to the emergency department for chest pain onset (CPO) of less than 6 hours.Participants: 449 patients were included, in whom 12% had NSTEMI. CPO occurred 4 hours in 146 patients. The prevalence of NSTEMI was similar in all groups (9%, 13% and 12%, respectively, p=0.281).Measures: Diagnostic performances of HS-cTn and copeptin at presentation were examined…
High-sensitivity troponin and novel biomarkers for the early diagnosis of non-ST-segment elevation myocardial infarction in patients with atrial fibr…
2015
To evaluate the diagnostic performance of high-sensitivity troponin I (hsTnI) and other novel biomarkers for diagnosing non-ST-segment elevation myocardial infarction (NSTEMI) in patients with atrial fibrillation.In an acute chest pain cohort (N=1673), mean age 61.4±13.6 (34% female), we measured hsTnI and 13 established and novel biomarkers reflecting ischaemia, necrosis, inflammation, myocardial stress, angiogenesis on admission and after three hours in order to investigate their diagnostic accuracy for NSTEMI.In atrial fibrillation patients (N=299) hsTnI on admission had the best discriminatory ability for NSTEMI (area under the curve 0.97) with only two novel biomarkers, copeptin and he…