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1.
Clin Oral Investig ; 23(1): 187-197, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29582152

RESUMEN

OBJECTIVES: Since early childhood caries (ECC) is a major disease in the public health sector, an interdisciplinary prevention concept to avert this disease was developed, launched in a project region, and evaluated. It was examined whether the emergence of ECC could be prevented or curbed with the newly developed program. MATERIALS AND METHODS: The program encompasses seven pulses of information from an interdisciplinary team (gynecologists, midwives, pediatricians, dentists, municipal social services, and the public health office). The primary dependent variables were caries experience and prevalence among the 3- to 4-year-olds who took part in the ECC prevention program, compared to children of the same age without such measures. The effect of the prevention program was assessed by means of a "historical" comparison. The dental diagnoses were performed by two calibrated dentists based on the "ICDAS collapsed." Data on diet and preventive behavior were gathered using a standardized parental questionnaire. The significance was tested using the nonparametric Mann-Whitney U test. RESULTS: There were 661 3- to 4-year-olds in the control group and 706 in the test group. The mean d3-6mf-t for the control group (0.92) was significantly higher than that for the test group (0.46). While 78.8% of the children examined in the control group exhibited predominantly sound primary dentition, this was the case for 86.3% of the test group. The proportion of children with S-ECC was 7.9% in the test group and 14.5% in the control group. The test group differed significantly from the control group both in terms of reported diet and dental hygiene habits. CONCLUSIONS AND CLINICAL RELEVANCE: The interdisciplinary prevention program presented here is an effective concept for preventing ECC and considerably helps reduce problems in the treatment of small children.


Asunto(s)
Atención Dental para Niños/organización & administración , Caries Dental/prevención & control , Prevención Primaria , Preescolar , Femenino , Alemania , Humanos , Masculino , Evaluación de Programas y Proyectos de Salud , Diente Primario , Resultado del Tratamiento
2.
Transfus Med Hemother ; 40(2): 109-16, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23652982

RESUMEN

BACKGROUND: Secretion of ADP and ATP is an essential prerequisite for platelet aggregation. Impaired nucleotide secretion can cause aggregation defects and increased bleeding risk. Quantitative determination of platelet nucleotide content and exocytosis is thus of importance for the characterization and diagnosis of bleeding phenotypes. For transgenic animal models with hemostatic defects analysis of potential secretion defects is as well imperative. METHODS: Supernatants of washed platelets and platelet-rich plasma were analyzed by HPLC for ADP and ATP concentration. Calibration of the HPLC data was accomplished with an internal standard compensating for loss of analyte, detection sensitivity, and interference of the biomatrix. RESULTS: HPLC analysis of nucleotide secretion was carried out with human and mouse platelets. Detection limits were determined for washed platelet and platelet-rich plasma samples. In the physiological concentration range linearity with respect to the peak area is maintained. CONCLUSION: The method combines reasonable sensitivity with robustness. The internal standard ensures reliable quantification of nucleotide concentrations even in presence of otherwise interfering substances. The low sample consumption renders possible the application to analysis of small samples like in mouse experiments.

3.
Ecol Evol ; 9(3): 1437-1451, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30805172

RESUMEN

We used an information theoretic approach to assess the effects of an ecologically adjusted sediment management scheme on grayling (Thymallus thymallus L. 1758) populations. Additionally to reservoir operation, candidate models included a variety of parameters and processes that may influence grayling populations such as flow, temperature, density dependence, and bird predation. Population parameters analyzed included total densities, young of the year numbers, and larval densities. These analyses were supplemented by a characterization of sediments and sedimentation patterns in the reach. Investigations were carried out in six sites affected by flushing and in one control site. A total of thirteen flushing operations have been undertaken within the study period leading to considerable remobilization of fine sediments and gravel. Due to seasonal and hydrological restrictions, not every flood could be used for flushing. These limitations led to an interrupted management throughout the chain of reservoirs as well as to long time intervals between flushing events with possible effects on spawning habitat quality. None of the investigated population parameters was affected by flushing, and thus, the study generally supports the current reservoir management scheme. Our analyses revealed the magnitude and timing of high water events, temperature, and density-dependent effects, that is, population densities the year before, as the most influential variables for grayling population dynamics in the investigated stretch. The siltation of reservoirs is a significant problem for reservoir storage, flood protection, river deltas, and coastal zones. Its management-which is inevitable to safeguard river deltas and secure flood protection-poses also the challenge to safeguard riverine ecosystems below reservoirs. Based on our experience, we propose a periodic flushing regime in concordance with the hydrograph thereby mimicking the timing, magnitude, frequency, and duration of natural SSC pulses and gravel transport. This flushing regime minimizes adverse downstream environmental impacts and maximizes benefits.

4.
Eur Heart J Cardiovasc Imaging ; 20(4): 467-474, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30102319

RESUMEN

AIMS: Although mortality rate is very high, diagnosis of acute myocarditis remains challenging with conventional tests. We aimed to elucidate the potential role of longitudinal 2-Deoxy-2-18F-fluoro-D-glucose (18F-FDG) positron emission tomography (PET) inflammation monitoring in a rat model of experimental autoimmune myocarditis. METHODS AND RESULTS: Autoimmune myocarditis was induced in Lewis rats by immunizing with porcine cardiac myosin emulsified in complete Freund's adjuvant. Time course of disease was assessed by longitudinal 18F-FDG PET imaging. A correlative analysis between in- and ex vivo18F-FDG signalling and macrophage infiltration using CD68 staining was conducted. Finally, immunohistochemistry analysis of the cell-adhesion markers CD34 and CD44 was performed at different disease stages determined by longitudinal 18F-FDG PET imaging. After immunization, myocarditis rats revealed a temporal increase in 18F-FDG uptake (peaked at week 3), which was followed by a rapid decline thereafter. Localization of CD68 positive cells was well correlated with in vivo18F-FDG PET signalling (R2 = 0.92) as well as with ex vivo18F-FDG autoradiography (R2 = 0.9, P < 0.001, respectively). CD44 positivity was primarily observed at tissue samples obtained at acute phase (i.e. at peak 18F-FDG uptake), while CD34-positive staining areas were predominantly identified in samples harvested at both sub-acute and chronic phases (i.e. at 18F-FDG decrease). CONCLUSION: 18F-FDG PET imaging can provide non-invasive serial monitoring of cardiac inflammation in a rat model of acute myocarditis.


Asunto(s)
Inflamación/diagnóstico por imagen , Miocarditis/diagnóstico por imagen , Tomografía de Emisión de Positrones , Enfermedad Aguda , Animales , Enfermedades Autoinmunes/complicaciones , Modelos Animales de Enfermedad , Femenino , Fluorodesoxiglucosa F18 , Miocarditis/etiología , Radiofármacos , Ratas , Ratas Endogámicas Lew
5.
J Nucl Med ; 57(12): 1985-1990, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27390159

RESUMEN

Myocarditis represents a major cause of dilated cardiomyopathy and sudden cardiac death in younger adults. Currently, definitive diagnosis of myocarditis requires endomyocardial biopsy, which is highly invasive and has the drawback of variable sensitivity due to inherent sampling error. Therefore, reliable noninvasive methods to detect and monitor cardiac inflammation are clinically relevant. In this study, we explored the potential of radiolabeled methionine to assess myocardial inflammatory activity in a rat model of experimental autoimmune myocarditis (EAM). METHODS: Autoimmune myocarditis was induced by immunizing Lewis rats twice with porcine cardiac myosin and Freund complete adjuvant. Control animals were treated with adjuvant alone. Dual-tracer autoradiography was performed to assess 14C-methionine uptake and to compare the distributions of 14C-methionine versus 18F-FDG. Hematoxylin and eosin staining and anti-CD68 macrophage staining were performed for histologic analysis. Additionally, cardiac 11C-methionine PET was performed to evaluate the feasibility of in vivo imaging. 18F-FDG PET was also conducted to compare the in vivo uptake of 11C-methionine and 18F-FDG. RESULTS: Multiple focal cardiac inflammatory lesions were histologically identified in myosin-immunized rats, whereas no cardiac lesions were observed in the controls. Autoradiographic images clearly showed a high-density accumulation of 14C-methionine in inflammatory lesions of EAM rats, whereas no significant uptake was observed in the control animals. 14C-methionine uptake was significantly higher in inflammatory lesions than in remote noninflammatory areas and control rat hearts. The distribution of 14C-methionine correlated well with that of 18F-FDG and with macrophage density. The contrast between inflammatory and noninflammatory areas was higher for 18F-FDG than for 14C-methionine (3.45 ± 0.68 vs. 2.07 ± 0.21, respectively; P < 0.05). In the PET imaging study, the regional 11C-methionine uptake (percentage injected dose per cubic centimeter) observed in EAM rats was significantly higher than the values obtained for control animals (0.64 ± 0.09 vs. 0.28 ± 0.02, respectively; P < 0.001). A good positive correlation between 11C-methionine and 18F-FDG uptake was found. CONCLUSION: In a rat model of autoimmune myocarditis, we demonstrated the colocalization of radiolabeled methionine accumulation with 18F-FDG uptake in histologically proven inflammatory lesions. These data suggest that 11C-methionine might represent a promising candidate for the noninvasive detection and monitoring of myocarditis.


Asunto(s)
Enfermedades Autoinmunes/diagnóstico por imagen , Radioisótopos de Carbono , Metionina , Miocarditis/diagnóstico por imagen , Tomografía de Emisión de Positrones , Animales , Enfermedades Autoinmunes/metabolismo , Transporte Biológico , Modelos Animales de Enfermedad , Femenino , Metionina/química , Metionina/metabolismo , Miocarditis/metabolismo , Ratas
6.
Ecol Evol ; 5(22): 5230-5239, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30151126

RESUMEN

In this study, we aim to gain a better insight on how habitat filtering due to urbanization shapes bird communities of Vienna city parks. This may help to derive implications for urban planning in order to promote and maintain high diversity and ecosystem function in an increasing urbanized environment. The structure of wintering bird communities of 36 Vienna city parks - surveyed once a month in January 2009, December 2009, December 2012, and January 2013 - was described by species richness and the functional diversity measurements FRic (functional richness), FEve (functional evenness), and FDiv (functional divergence). Environmental filtering was quantified by park size, canopy heterogeneity within the park, and the proportion of sealed area surrounding each park. Species richness, FRic, and FDiv increased with increasing park size. Sealed area had a strong negative effect on species richness and FDiv. Canopy heterogeneity played a minor role in explaining variance in FDiv data. FEve did not respond to any of these park parameters. Our results suggest a loss of species richness and functional diversity, hence most likely indicate a decline in ecosystem function, with decreasing park size and increasing sealed area of the surrounding urban landscape matrix.

7.
Proteins ; 55(3): 711-23, 2004 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-15103633

RESUMEN

The fact that hydrogen bonds (HBs) can provide major stabilization to transition states (TSs) of enzymatic reactions is well known. However, the nature of HB stabilization has been the subject of a significant controversy. It is not entirely clear if this stabilization is associated with electrostatic effects of preorganized dipoles or with delocalized resonance effects of the so-called low barrier hydrogen bond (LBHB). One of the best test cases for the LBHB proposal is the complex of chymotrypsin and trifluoromethyl ketone (TFK). It has been argued that the pK(a) shift in this system provides an experimental evidence for the LBHB proposal. However, this argument could not be resolved by experimental studies. Here we explore the nature of the Asp102-His57 pair in the chymotrypsin-TFK complex by a systematic computational and conceptual study. We start by defining the LBHB proposal in a unique energy-based way. We show that a consistent analysis must involve a description in terms of the energy of the two resonance structures and their mixing. It is clarified that LBHBs cannot be defined according to strength or distance, because ionic HBs can also be strong and short. Similarly, NMR chemical shifts and fractionation factors cannot be used to identify LBHBs in a conclusive way. It is also clarified that HBs with a significant asymmetry cannot be classified as LBHBs, because this contradicts the assumption of equal pK(a) of the donor and acceptor. Thus, the main issue is the DeltapK(a) and the corresponding energy difference. With this definition in mind, we calculate the free energy surface of proton transfer in this pair and evaluate the energetics of the different ionization states of this system. The calculations are done by both the semimacroscopic version of the protein dipoles Langevin dipoles (PDLD/S-LRA) model and by the empirical valence bond (EVB) method. The calculations establish that the LBHB proposal is not valid in the chymotrypsin-TFK complex and in other serine proteases. Although previous theoretical studies reached similar conclusion, this is the first time that the same set of free energy calculations reproduce all the known pK(a) values and pK(a) changes in the system, while evaluating the energetics and covalent character of the His-Asp system. The present study provides a support to the idea that enzymes work by creating a preorganized polar environment.


Asunto(s)
Ácido Aspártico/química , Histidina/química , Modelos Químicos , Serina Endopeptidasas/química , Sitios de Unión , Catálisis , Quimotripsina/química , Enlace de Hidrógeno , Modelos Moleculares , Serina Endopeptidasas/metabolismo
8.
Mol Biosyst ; 10(8): 2082-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24852796

RESUMEN

A kinetic description of the fragile equilibrium in thrombozytes regulating blood flow would be an important basis for rational medical interventions. Challenges for such a model include regulation by a complex bistability switch that determines the transition from reversible to irreversible aggregation and sparse data on the kinetics. A so far scarcely applied technique is given by the derivation of ordinary differential equations from Boolean expressions, which are called logic ODEs. We employ a combination of light-scattering based thrombocyte aggregation data, western blot and calcium measurements to compare three different ODE approaches regarding their suitability to achieve a data-consistent model of the switch. Our analysis reveals the standardized qualitative dynamical system approach (SQUAD) to be a better choice than classical mass action formalisms. Furthermore, we analyze the dynamical properties of the platelet aggregation threshold as a basis for medical interventions such as novel platelet aggregation inhibitors.


Asunto(s)
Simulación de Dinámica Molecular , Agregación Plaquetaria , Algoritmos , Biología Computacional/métodos , Humanos , Inhibidores de Agregación Plaquetaria
9.
Neuropsychopharmacology ; 39(5): 1196-205, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24247043

RESUMEN

The single-nucleotide polymorphism (SNP) rs1344706 in ZNF804A is one of the best-supported risk variants for psychosis. We hypothesized that this SNP contributes to the development of schizophrenia by affecting the ability to understand other people's mental states. This skill, commonly referred to as Theory of Mind (ToM), has consistently been found to be impaired in schizophrenia. Using functional magnetic resonance imaging, we previously showed that in healthy individuals rs1344706 impacted on activity and connectivity of key areas of the ToM network, including the dorsomedial prefrontal cortex, temporo-parietal junction, and the posterior cingulate cortex, which show aberrant activity in schizophrenia patients, too. We aimed to replicate these results in an independent sample of 188 healthy German volunteers. In order to assess the reliability of brain activity elicited by the ToM task, 25 participants performed the task twice with an interval of 14 days showing excellent accordance in recruitment of key ToM areas. Confirming our previous results, we observed decreasing activity of the left temporo-parietal junction, dorsomedial prefrontal cortex, and the posterior cingulate cortex with increasing number of risk alleles during ToM. Complementing our replication sample with the discovery sample, analyzed in a previous report (total N=297), further revealed negative genotype effects in the left dorsomedial prefrontal cortex as well as in the temporal and parietal regions. In addition, as shown previously, rs1344706 risk allele dose positively predicted increased frontal-temporo-parietal connectivity. These findings confirm the effects of the psychosis risk variant in ZNF804A on the dysfunction of the ToM network.


Asunto(s)
Encéfalo/fisiología , Factores de Transcripción de Tipo Kruppel/genética , Polimorfismo de Nucleótido Simple , Teoría de la Mente , Adulto , Alelos , Mapeo Encefálico , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Técnicas de Genotipaje , Alemania , Humanos , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/fisiología , Pruebas Neuropsicológicas , Trastornos Psicóticos/genética , Reproducibilidad de los Resultados , Factores de Riesgo , Análisis y Desempeño de Tareas
11.
J Proteome Res ; 8(4): 1818-27, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19249851

RESUMEN

In fish of the genus Xiphophorus, different grades of pigment cell lesions from nevi to melanoma can be gained by simple crossbreeding. With this model, one can easily access tissues of different malignancies from animals with highly identical genetic background. To find protein expression differences between healthy, benign and malignant tissues, we performed 2D PAGE and DIGE and found among regulated proteins antioxidant proteins that were overexpressed with increasing malignancy.


Asunto(s)
Transformación Celular Neoplásica , Ciprinodontiformes/metabolismo , Melanoma Experimental/metabolismo , Proteoma/metabolismo , Neoplasias Cutáneas/metabolismo , Animales , Biomarcadores de Tumor/metabolismo , Electroforesis en Gel Bidimensional , Humanos
12.
J Proteome Res ; 7(2): 526-34, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18088087

RESUMEN

Beside their main physiological function in hemostasis, platelets are also highly involved in pathological processes, such as atherothrombosis and inflammation. During hemostasis, binding of adhesive substrates to tyrosine-kinase-linked adhesion receptors and/or soluble agonists to G-protein coupled receptors leads to a cascade of intracellular signaling processes based on substrate (de)phosphorylation. The same mechanisms are involved in platelet activation at sites of atherosclerotic plaque rupture, contributing to vessel occlusion and consequently to pathologic states, such as myocardial infarction, stroke, or peripheral artery disease. To gain a deeper insight into platelet function, we analyzed the phosphoproteome of resting platelets and identified 564 phosphorylation sites from more than 270 proteins, of which many have not been described in platelets before. Among those were several unknown potential protein kinase A (PKA) and protein kinase G (PKG) substrates. Because platelet inhibition is tightly regulated especially by PKA and PKG activity, these proteins may represent important new targets for cardiovascular research. Thus, our finding that GPIbalpha is phosphorylated at Ser603 in resting platelets may represent a novel mechanism for the regulation of one of the most important platelet receptor (GPIb-IX-V) mediated signaling pathways by PKA/PKG.


Asunto(s)
Plaquetas/metabolismo , Fosfoproteínas/sangre , Proteoma/metabolismo , Fase de Descanso del Ciclo Celular/fisiología , Plaquetas/citología , Cromatografía de Afinidad , Cromatografía por Intercambio Iónico , Humanos , Fosfopéptidos/sangre , Fosfopéptidos/clasificación , Fosfoproteínas/clasificación , Fosforilación , Activación Plaquetaria/fisiología , Espectrometría de Masas en Tándem
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