ZusammenfassungDer Fragebogen „Monitoring of Exacerbation Probability“ (MEP) ist ein neuartiges, ... more ZusammenfassungDer Fragebogen „Monitoring of Exacerbation Probability“ (MEP) ist ein neuartiges, einfaches Instrument zur Unterstützung der Erkennung und semiquantitativen numerischen Dokumentation von Exazerbationen (ECOPD) in der täglichen Routine. In einer prospektiven, multizentrischen Studie an 810 Patienten in 21 Zentren wurde MEP unter realen Bedingungen bewertet und mit der Anwendung des EXACT-Pro-Fragebogen bei 3751 Visiten verglichen. Die in diese Studie eingeschlossene Population von COPD-Patienten ist demografisch und klinisch typisch für die gesamte COPD-Population. Da ein MEP-Wert von 1 oder mehr als positives Testergebnis definiert wurde, ergab sich eine Sensitivität von 91% und eine Spezifität von 66%. Außerdem korrelierten die MEP-Ergebnisse eindeutig mit den EXACT-Pro-Ergebnissen. Dies qualifiziert den MEP-Fragebogen als valides Instrument zur erleichterten Erkennung von ECOPD und zur longitudinalen Charakterisierung von COPD-Patienten.
Introduction In vitro expansion and differentiation of mesenchymal stem cells (MSCs) rely on spec... more Introduction In vitro expansion and differentiation of mesenchymal stem cells (MSCs) rely on specific environmental conditions. One crucial factor is the oxygen tension. Low oxygen tension improves MSC expansion in vitro. Moreover, it accelerates the induction of a chondrogenic phenotype in subsequent 3D differentiation cultures. However, clones of MSCs from the same donor often differ in their in vitro properties. This kind of heterogeneity has been suggested to originate from an individual decline in MSC function called ‘stem cell ageing’. For therapeutic applications of MSCs in cartilage repair understanding the interdependency of environmental regulation and stem cell aging is crucial.
The haematopoietic stem cell (HSC) niche provides essential micro-environmental cues for the prod... more The haematopoietic stem cell (HSC) niche provides essential micro-environmental cues for the production and maintenance of HSCs within the bone marrow. During inflammation, haematopoietic dynamics are perturbed, but it is not known whether changes to the HSC-niche interaction occur as a result. We visualise HSCs directly in vivo, enabling detailed analysis of the 3D niche dynamics and migration patterns in murine bone marrow following Trichinella spiralis infection. Spatial statistical analysis of these HSC trajectories reveals two distinct modes of HSC behaviour: (i) a pattern of revisiting previously explored space, and (ii) a pattern of exploring new space. Whereas HSCs from control donors predominantly follow pattern (i), those from infected mice adopt both strategies. Using detailed computational analyses of cell migration tracks and life-history theory, we show that the increased motility of HSCs following infection can, perhaps counterintuitively, enable mice to cope better i...
This study was self-funded Background: Cleft defects are one of the most frequent birth-deformiti... more This study was self-funded Background: Cleft defects are one of the most frequent birth-deformities of the orofacial region and they are commonly associated with anomalies of the tooth structure, size, shape, formation, eruption, and tooth number. The aim of our study was to evaluate the prevalence, distribution, and potential association of combined hypodontia in cleft-affected patients with regard to all types of teeth in both jaws in the permanent dentition. Material/Methods: This retrospective radiographic analysis included patients with various types of clefts treated orthodontically in the
We study the phase transition of the three-dimensional complex |ψ| 4 theory by considering the ge... more We study the phase transition of the three-dimensional complex |ψ| 4 theory by considering the geometrically defined vortex-loop network as well as the magnetic properties of the system in the vicinity of the critical point. Using high-precision Monte Carlo techniques we examine an alternative formulation of the geometrical excitations in relation to the global O(2)-symmetry breaking, and check if both of them exhibit the same critical behavior leading to the same critical exponents and therefore to a consistent description of the phase transition. Different percolation observables are taken into account and compared with each other. We find that different definitions of constructing the vortex-loop network lead to different results in the thermodynamic limit, and the percolation thresholds do not coincide with the thermodynamic phase transition point.
Background-Diagnosis of phaeochromocytoma is commonly performed by measurements of plasma free no... more Background-Diagnosis of phaeochromocytoma is commonly performed by measurements of plasma free normetanephrine and metanephrine. Plasma deconjugated normetanephrine and metanephrine have been proposed as alternative equivalent, but easier to measure biomarkers. Objective-The aim of this study was to compare the diagnostic performances of plasma free versus deconjugated normetanephrine and metanephrine in patients tested for phaeochromocytoma. Methods-The study population included a reference group of 262 normotensive and hypertensive volunteers, 198 patients with phaeochromocytoma and 528 patients initially suspected of having the tumour, but with negative investigations after at least 2 years of follow up. Measurements were performed using liquid chromatography with electrochemical detection. Results-Median plasma concentrations of free normetanephrine were 17-fold higher in patients with phaeochromocytoma than in the reference population, a 72% larger (p<0.001) difference than that for the 10-fold higher levels of plasma deconjugated normetanephrine. In contrast, relative increases of plasma concentrations of free and deconjugated metanephrine were similar. Using upper cutoffs established in the reference population, measurements of plasma free metabolites provided superior diagnostic performance than deconjugated metabolites according to measures of both sensitivity (97% vs 92%, p=0.002) and specificity (93 vs 89%, p=0.012). The area under the receiver operating characteristic curve for the free metabolites was larger than that for the deconjugated metabolites (0.986 vs 0.965, p<0.001). Conclusion-Measurements of plasma free normetanephrine and metanephrine are superior to the deconjugated metabolites for diagnosis of phaeochromocytoma.
ZusammenfassungDer Fragebogen „Monitoring of Exacerbation Probability“ (MEP) ist ein neuartiges, ... more ZusammenfassungDer Fragebogen „Monitoring of Exacerbation Probability“ (MEP) ist ein neuartiges, einfaches Instrument zur Unterstützung der Erkennung und semiquantitativen numerischen Dokumentation von Exazerbationen (ECOPD) in der täglichen Routine. In einer prospektiven, multizentrischen Studie an 810 Patienten in 21 Zentren wurde MEP unter realen Bedingungen bewertet und mit der Anwendung des EXACT-Pro-Fragebogen bei 3751 Visiten verglichen. Die in diese Studie eingeschlossene Population von COPD-Patienten ist demografisch und klinisch typisch für die gesamte COPD-Population. Da ein MEP-Wert von 1 oder mehr als positives Testergebnis definiert wurde, ergab sich eine Sensitivität von 91% und eine Spezifität von 66%. Außerdem korrelierten die MEP-Ergebnisse eindeutig mit den EXACT-Pro-Ergebnissen. Dies qualifiziert den MEP-Fragebogen als valides Instrument zur erleichterten Erkennung von ECOPD und zur longitudinalen Charakterisierung von COPD-Patienten.
Introduction In vitro expansion and differentiation of mesenchymal stem cells (MSCs) rely on spec... more Introduction In vitro expansion and differentiation of mesenchymal stem cells (MSCs) rely on specific environmental conditions. One crucial factor is the oxygen tension. Low oxygen tension improves MSC expansion in vitro. Moreover, it accelerates the induction of a chondrogenic phenotype in subsequent 3D differentiation cultures. However, clones of MSCs from the same donor often differ in their in vitro properties. This kind of heterogeneity has been suggested to originate from an individual decline in MSC function called ‘stem cell ageing’. For therapeutic applications of MSCs in cartilage repair understanding the interdependency of environmental regulation and stem cell aging is crucial.
The haematopoietic stem cell (HSC) niche provides essential micro-environmental cues for the prod... more The haematopoietic stem cell (HSC) niche provides essential micro-environmental cues for the production and maintenance of HSCs within the bone marrow. During inflammation, haematopoietic dynamics are perturbed, but it is not known whether changes to the HSC-niche interaction occur as a result. We visualise HSCs directly in vivo, enabling detailed analysis of the 3D niche dynamics and migration patterns in murine bone marrow following Trichinella spiralis infection. Spatial statistical analysis of these HSC trajectories reveals two distinct modes of HSC behaviour: (i) a pattern of revisiting previously explored space, and (ii) a pattern of exploring new space. Whereas HSCs from control donors predominantly follow pattern (i), those from infected mice adopt both strategies. Using detailed computational analyses of cell migration tracks and life-history theory, we show that the increased motility of HSCs following infection can, perhaps counterintuitively, enable mice to cope better i...
This study was self-funded Background: Cleft defects are one of the most frequent birth-deformiti... more This study was self-funded Background: Cleft defects are one of the most frequent birth-deformities of the orofacial region and they are commonly associated with anomalies of the tooth structure, size, shape, formation, eruption, and tooth number. The aim of our study was to evaluate the prevalence, distribution, and potential association of combined hypodontia in cleft-affected patients with regard to all types of teeth in both jaws in the permanent dentition. Material/Methods: This retrospective radiographic analysis included patients with various types of clefts treated orthodontically in the
We study the phase transition of the three-dimensional complex |ψ| 4 theory by considering the ge... more We study the phase transition of the three-dimensional complex |ψ| 4 theory by considering the geometrically defined vortex-loop network as well as the magnetic properties of the system in the vicinity of the critical point. Using high-precision Monte Carlo techniques we examine an alternative formulation of the geometrical excitations in relation to the global O(2)-symmetry breaking, and check if both of them exhibit the same critical behavior leading to the same critical exponents and therefore to a consistent description of the phase transition. Different percolation observables are taken into account and compared with each other. We find that different definitions of constructing the vortex-loop network lead to different results in the thermodynamic limit, and the percolation thresholds do not coincide with the thermodynamic phase transition point.
Background-Diagnosis of phaeochromocytoma is commonly performed by measurements of plasma free no... more Background-Diagnosis of phaeochromocytoma is commonly performed by measurements of plasma free normetanephrine and metanephrine. Plasma deconjugated normetanephrine and metanephrine have been proposed as alternative equivalent, but easier to measure biomarkers. Objective-The aim of this study was to compare the diagnostic performances of plasma free versus deconjugated normetanephrine and metanephrine in patients tested for phaeochromocytoma. Methods-The study population included a reference group of 262 normotensive and hypertensive volunteers, 198 patients with phaeochromocytoma and 528 patients initially suspected of having the tumour, but with negative investigations after at least 2 years of follow up. Measurements were performed using liquid chromatography with electrochemical detection. Results-Median plasma concentrations of free normetanephrine were 17-fold higher in patients with phaeochromocytoma than in the reference population, a 72% larger (p<0.001) difference than that for the 10-fold higher levels of plasma deconjugated normetanephrine. In contrast, relative increases of plasma concentrations of free and deconjugated metanephrine were similar. Using upper cutoffs established in the reference population, measurements of plasma free metabolites provided superior diagnostic performance than deconjugated metabolites according to measures of both sensitivity (97% vs 92%, p=0.002) and specificity (93 vs 89%, p=0.012). The area under the receiver operating characteristic curve for the free metabolites was larger than that for the deconjugated metabolites (0.986 vs 0.965, p<0.001). Conclusion-Measurements of plasma free normetanephrine and metanephrine are superior to the deconjugated metabolites for diagnosis of phaeochromocytoma.
Uploads
Papers by Axel Krinner