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Background: This study aims to assess the role of ductoscopy for detecting intraductal anomalies in patients with nipple discharge in comparison to conventional tests and to find an effective combination of both approaches. Materials and Methods: Prior to duct excision, ductoscopy was performed in 97 women. Histologic and all other diagnostic results were compared. Sensitivity, specificity, and efficiency were calculated for all methods. These parameters were also calculated for all possible test combinations in 12 patients who had completed all tests. Results: Breast sonography reached the highest sensitivity (64.1%) and efficiency (64%); mammography had the highest specificity (100%). The sensitivity of ductoscopy was 53.2%, its specificity 60%, and its efficiency 55.1%. Among combinations of all methods, the combination ductoscopy + galactography was the most sensitive (80%). Mammography, magnetic resonance imaging, and ductoscopy were each 100% specific. Ductoscopy was the most efficient (75%) single method. Conclusion: Ductoscopy is a valuable test for diagnosing intraductal lesions in patients with nipple discharge. It is more efficient than conventional tests in patients undergoing all tests.
Sealing ability of ProRoot MTA when placed as an apical barrier using three different techniques
(2013)
A one-visit apexification protocol with Mineral Trioxide Aggregate (MTA) can be seen as an alternative to the traditional treatment practices with calcium hydroxide. The aim of this study was to investigate the sealing ability of ProRoot MTA when placed as an apical barrier using three different techniques. Sixty freshly extracted single-rooted human teeth were decoronated and standardized to a root length of 15mm. The root segments were prepared with Gates Glidden burs (size 1-6) to simulate the clinical situation of an open apex and randomly assigned into 3 experimental groups of 20 samples each. 5mm MTA was placed by pluggers (Group 1) paper points (Group 2) or ultrasonic tips (Group 3). Radiographs were taken to verify the placement of the apical barriers. After obturation of all samples with warm gutta-percha (Obtura) and AH26 sealer, the coronal portion of all samples was sealed with Cavit. The root segments were then double coated with nail varnish except for the open apex and were exposed to methylene blue dye for 48 hours at room temperature. Afterwards, the samples were sectioned longitudinally and the extent of dye penetration was measured with a stereomicroscope. The mean depth of dye leakage for Group 1 was 1.34mm (±0.5 SD) Group 2 1.25mm (±0.4 SD) and Group 3 1.14mm (± 0.4 SD). Statistical analysis showed that there were no significant differences among the 3 experimental groups (0.178<p<0.552). In conclusion, ProRoot MTA has a similar sealing ability when placed as an apical barrier with pluggers, paper points or ultrasonic tips.
Until now proximal caries is still a significant problem in the clinical dentistry in spite of the caries decline recently. As resin infiltration offers a new micro-invasive treatment to arrest the progression of proximal initial carious lesions, this study aimed to evaluate its clinical applicability, safety and effect. In the study population of 50 children, adolescents and young adults (mean age 17.9 years ± 6.8), ten dentists at University of Greifswald applied the infiltration material ICON® (DMG, Germany) on non-cavitated proximal lesions in permanent and primary teeth as described in the manual instructions from the producer. The results showed good patient satisfaction with the procedure. The time for the infiltration (24.3 min ± 7.4), which included rubber dam application (7.7 min ± 4), and the effort were perceived as comparable to a composite filling by the dentist or as even easier. In three patients (6%), it was not possible to gain sufficient proximal space for the application of an infiltration. The location of the infiltrated tooth, separation problems as well as the routine of the dentists with the infiltration technique had an effect on the duration of the infiltration. A clear learning curve with a reduction of treatment time for subsequent treatments was observed (P < 0.001). Within the follow-up interval of 12 months, vitality of all infiltrated teeth was still positive and no relevant differences in plaque accumulation or gingival status were recorded. In addition, the infiltrated surfaces showed smooth margins and considerable decrease in the discoloration. In the radiographic evaluation after one year, only two lesions (4.7%) have progressed. Thus, caries infiltration is an applicable method for the treatment of initial non-cavitated proximal lesions without prior temporary tooth separation. Even without special training it can be applied easily by dentist and they experience a clear learning curve within the first 5-10 applications. In addition, the infiltration technique shows a high acceptance by the patients. Furthermore, caries infiltration lead to very good results regarding safety and preventing the lesion progression of non-cavitated proximal caries lesions located in the enamel or in the outer third of dentin.
There is a growing interest in the application of non-thermal atmospheric pressure plasma for the treatment of wounds. Due to the generation of various ROS and RNS, UV radiation and electric fields plasma is a very promising tool which can stimulate skin and immune cells. However, not much is known about the mammalian cell responses after plasma treatments on a molecular level. The present work focusses on the impact of plasma on cell signaling in the human keratinocyte cell line HaCaT by using the methods DNA microarray, qPCR, ELISA and flow cytometry. Here, cell signaling mediators such as cytokines and growth factors which could promote wound healing by enhancing angiogenesis, reepithelization, migration and proliferation were of major interest. Additionally, the crosstalk between keratinocytes and monocytes was studied using a co-culture. For the first time extensive investigations on the impact of plasma on cell signaling in human keratinocytes were conducted. The most prominent cytokines and growth factors which were regulated by plasma at gene and protein level were VEGF-A, GM-CSF, HB-EGF, IL-8, and IL-6. The latter was not activated due to the JAK/STAT-pathway but probably by a combined activation of MAPK- and PI3K/Akt-pathways. By the use of conditioned medium it was found out that ROS and RNS generated directly after plasma treatment induced larger effects on cell signaling in keratinocytes than the subsequently secreted growth factors and cytokines. Furthermore, monocytes and keratinocytes hardly altered their secretion profiles in co-culture. From these results it is deduced that the plasma generated reactive species are the main actors during cell signaling. In order to differentiate the impact of ROS and RNS on the cellular response the ambience of the plasma effluent was controlled, varying the ambient gas composition from pure nitrogen to pure oxygen. Thereby a first step towards the attribution of the cellular response to specific plasma generated reactive species was achieved. While IL-6 expression correlated with ROS generated by the plasma source, the cell signaling mediators VEGF-A, GM-CSF and HB-EGF were significantly changed by RONS. Above all hydrogen peroxide was found to play a dominant role for observed cell responses. In summary, plasma activates wound healing related cell signaling mediators as cytokines and growth factors in keratinocytes. It was also shown that the generated reactive species mainly induced cell signaling. For the first time cell responses can be correlated to ROS and RONS in plasma treated cells. These results underline the potential of non-thermal atmospheric pressure plasma sources for their applications in wound treatment.
Abstract
Many processes in nature are governed by the interaction of electro-magnetic radiation with matter. New tools such as femtosecond and free-electron lasers allow one to study the interaction in unprecedented detail with high temporal and spatial resolution. In addition, much work is devoted to the exploration of novel target systems that couple to radiation in an effective and controllable way or that could serve as efficient sources of energetic particles when being subjected to intense laser fields. The interaction between matter and radiation fields as well as their mutual modification via correlations constitutes a rich field of research that is impossible to cover exhaustively. The papers in this focus issue represent a selection that largely reflects the program of the international conference on ‘Correlation Effects in Radiation Fields’ held in 2011 in Rostock, Germany.
Background/Aims: Only a small percentage of pathological gamblers utilizes professional treatment for gambling problems. Little is known about which social and gambling-related factors are associated with treatment utilization. The aim of this study was to look for factors associated with treatment utilization for pathological gambling. Methods: The study followed a sampling design with 3 different recruitment channels, namely (1) a general population-based telephone sample, (2) a gambling location sample and (3) a project telephone hotline. Pathological gambling was diagnosed in a telephone interview. Participants with pathological gambling (n = 395) received an in-depth clinical interview concerning treatment utilization, comorbid psychiatric disorders and social characteristics. Results: Variables associated with treatment were higher age [odds ratio (OR) 1.05, 95% confidence interval (CI) 1.03-1.08], an increased number of DSM-IV criteria for pathological gambling (OR 1.34, 95% CI 1.06-1.70), more adverse consequences from gambling (OR 1.10, 95% CI 1.03-1.16) and more social pressure from significant others (OR 1.17, 95% CI 1.07-1.27). Affective disorders were associated with treatment utilization in the univariate analysis (OR 1.81, 95% CI 1.19-2.73), but multivariate analysis showed that comorbid psychiatric disorders were not independently associated. Conclusion: These results indicate that individuals with more severe gambling problems utilize treatment at an older age when more adverse consequences have occurred. Further research should focus on proactive early interventions.
Background: Primary angiitis of the central nervous system (PACNS) is a rare but serious condition. A fraction of patients suffering from PACNS concurrently exhibit pronounced cerebral amyloid angiopathy (CAA) which is characterized by deposits of amyloid-β (Aβ) in and around the walls of small and medium-sized arteries of the brain. PACNS with CAA has been identified as a distinct disease entity, termed Aβ-related angiitis (ABRA). Evidence points to an immune reaction to vessel wall Aβ as the trigger of vasculitis. Objective: To investigate whether the inflammatory response to Aβ has (1) any effect on the status of immune activation in the brain parenchyma and (2) leads to clearance of Aβ from brain parenchyma. Methods: We studied immune activation and Aβ load by quantitative immunohistochemical analysis in brain parenchyma adjacent to affected vessels in 11 ABRA patients and 10 matched CAA controls. Results: ABRA patients showed significantly increased immune activation and decreased Aβ loads in the brain parenchyma adjacent to affected vessels. Conclusion: Our results are in line with the hypothesis of ABRA being the result of an excessive immune response to Aβ and show that this can lead to enhanced clearance of Aβ from the brain parenchyma by immune-mediated mechanisms.
Reactive oxygen species (ROS) can damage all cellular macromolecules and also produce secondary reactive intermediates, like reactive electrophilic species (RES) that include quinones or aldehydes. Low molecular weight (LMW) thiols are small thiol-containing compounds that play essential roles in the defense against ROS and RES in all organisms. The best studied LMW thiol is the tripeptide glutathione (GSH). Firmicutes bacteria including Bacillus und Staphylococcus species have been recently discovered to utilize the redox buffer bacillithiol (BSH). LMW thiols function as redox buffers to maintain the reduced state of the cytoplasm. Under conditions of oxidative stress, LMW thiols also react with protein thiols to form mixed LMW thiol – protein disulfides, termed S-thiolations, as major protection mechanism. Investigating the role of BSH in oxidative stress response and ROS-induced S-thiolations in Firmicutes bacteria was one subject of this PhD thesis. Specifically, the regulatory mechanisms and post-translational thiol-modifications in response to NaOCl stress were studied in the model bacterium for low-GC Gram-positive bacteria Bacillus subtilis. The transcriptome profile after NaOCl stress was indicative of disulfide stress and overlapped strongly with the response to diamide. NaOCl stress caused induction of the thiol- and oxidative stress-specific Spx, CtsR, PerR and OhrR regulons. Thiol redox proteomics identified only few NaOCl-sensitive proteins with reversible thiol-oxidations. Using mass spectrometry, eleven proteins were identified that were oxidized to mixed BSH protein disulfides (S-bacillithiolated) in B. subtilis cells after NaOCl-exposure. Methionine synthase MetE is the most abundant S-bacillithiolated protein in B. subtilis and other Bacillus species after NaOCl exposure. S-bacillithiolation of OhrR repressor leads to upregulation of the OhrA peroxiredoxin that confers together with BSH specific protection against NaOCl. S-bacillithiolation of MetE, YxjG, PpaC, and SerA causes hypochlorite-induced methionine starvation as supported by the induction of the S-box regulon. To further assess the conservation of targets for S-bacillithiolations in other Firmicutes bacteria, we studied the S-bacillithiolomes of Bacillus megaterium, Bacillus pumilus, Bacillus amyloliquefaciens, and Staphylococcus carnosus under NaOCl stress conditions. In total, 54 S-bacillithiolated proteins were identified, including 29 unique proteins and 8 conserved proteins involved in amino acid and cofactor biosynthesis, nucleotide metabolism, translation, protein quality control, redox and antioxidant functions. Together our data support a major role of BSH redox buffer in redox control and thiol protection of conserved and essential proteins against irreversible oxidation by S-bacillithiolations in Firmicutes bacteria. In response to ROS and RES, bacteria also activate the expression of antioxidant and detoxification enzymes, such as catalases, peroxidases, thiol-dependent peroxiredoxins and other specific oxidoreductases to detoxify ROS and RES. These defense mechanisms are often controlled by redox-sensitive transcription factors. B. subtilis encodes redox-sensing MarR-type regulators belonging to the OhrR and DUF24-families that are conserved among bacteria. Hence, we were further interested in this PhD thesis to study at the molecular and structural level the redox-sensing mechanisms of novel redox-sensing MarR/DUF24-type regulators in B. subtilis. We have characterized the regulatory mechanisms of HypR, YodB and CatR that sense and respond to hypochlorite, diamide and quinones stress. HypR is the first DUF24-family regulator whose crystal structure was resolved. HypR senses specifically disulfide stress and controls positively expression of the flavin oxidoreductase HypO after NaOCl and diamide stress. HypR resembles a 2-Cys-type regulator with a reactive nucleophilic N-terminal Cys14 and a second C-terminal Cys49. Besides HypR, B. subtilis encodes further MarR/DUF24-family members including the paralogous YodB and CatR repressors that sense quinones and diamide. YodB controls the azoreductase AzoR1, the nitroreductase YodC, and the Spx regulator. YodB resembles a 2-Cys-type MarR/DUF24-family regulator with three Cys residues (Cys6, Cys101, and Cys108) that form intermolecular disulfides in vivo under oxidative stress. YodB and its paralog CatR were further identified as repressors of the catDE operon encoding a catechol-2,3-dioxygenase that also contributes to quinone resistance. Although CatR is a 1-Cys-type regulator, our data showed that CatR also forms intermolecular disulfide in response to diamide and quinones in vitro. Thus, HypR, YodB and CatR are controlled by 2-Cys-type thiol-disulfide redox switches to sense disulfide and RES stress conditions, and to control specific RES detoxification enzymes.
In terms of climate change and climate change mitigation, the quantitative knowledge of global carbon pools is important information. On the one hand, knowledge on the amount of carbon cycling among – and stored in – global pools (i.e. Atmosphere, Biosphere, Cryosphere, Hydrosphere, and Lithosphere) may improve the reliability of models predicting atmospheric CO2 concentrations in terms of fossil fuel combustion. On the other hand, the carbon sequestration potential of specific ecosystems allows for estimating their feasibility regarding carbon trade mechanisms such as the Clean Development Mechanism or the Reducing Emissions from Deforestation and Degradation Program (REDD+). However, up to date, the majority of terrestrial carbon assessments have focused on forests and peatlands, leaving a data gap open regarding the remaining ecosystems. This data gap is likely to be explained by the relatively high carbon densities and/or productivities of forests and peatlands. Nevertheless, to get a precise as possible global picture, information on carbon pools and sequestration of other ecosystems is needed. Although desert ecosystems generally express low carbon densities, they may absolutely store a remarkable amount of carbon due to their large areal extent. In this context, Central Asian Deserts (in particular within the Turanian Deserts, i.e. Karakum, Kysylkum, Muyunkum) likely inhibit comparably high carbon pools as they express a sparse vegetation cover due to an exceptionally high annual precipitation if compared to the World’s deserts. In this dissertation, three important woody plant species – Populus euphratica and Haloxylon aphyllum and Haloxylon persicum – of Central Asian Deserts were investigated for their carbon pools and carbon sequestration potential. These species were chosen as they I) locally express high carbon densities, II) are dominant species, III) have a rather large spatial distribution, and IV) have experienced a strong degradation throughout the 20th century. Thus, they likely show a remarkable potential for carbon re-sequestration through restoration and thus for an application of carbon trade mechanisms (CHAPTER I). P. euphratica was investigated in the nature reserve Kabakly at the Amu Darya, Turkmenistan and in Iminqak at the Tarim He, Xinjiang, China. The assessment of Haloxylon species was restricted to the Turanian deserts west of the Tain Shan. To achieve a first scientific basis for large scale estimates, different methodologies, ranging from allometric formulas, over dendrochronology to remote sensing were combined (CHAPTERS II-V). In CHAPTER II allometric formulas were successfully developed for Haloxylon aphyllum and Haloxylon persicum and applied to six study sites distributed over the Turanian Deserts to represent the allometric variability of Haloxylon species in Central Asia. CHAPTER III derives another allometric formula (only based on canopy area) for H. aphyllum and combines it with a remote sensing analysis from the nature reserve Repetek. Thereby, a first large scale estimate covering the Northeastern Karakum Desert of carbon pools related to mono specific H. aphyllum stands is achieved. CHAPTER IV describes the wood structure of Populus euphratica forests in the nature reserve Kabakly (Turkmenistan) and in Iminqak (Xinjiang, China). In CHAPTER V a dendrochronological approach derives models for predicting the Net Primary Productivity (NPP) and the age of P. euphratica in the nature reserve Kabakly. Thereby, a first feasibility assessment regarding remote sensing analyses and the upscaling of the obtained NPP results is carried out. First estimates based on these local studies (CHAPTER VI), reveal carbon densities ranging from 0.1 – 26.3 t C ha 1 for the three investigated species. Highest maximum and median carbon densities were found for P. euphratica, but Haloxylon aphyllum expressed remarkable maximum carbon densities (13.1 t C ha-1), too. The total carbon pools were estimated at 6480 kt C for P. euphratica, 520 kt C for H. aphyllum stands and 6900 kt C for Haloxylon persicum shrubland. Accounting for the extent of degraded areas, the total re-sequestration potentials of the respective species were estimated at 4320 kt C, 1620 kt C and 21900 kt C, this highlighting the remarkable absolute re-sequestration potential of H. persicum shrubland despite its low average carbon densities. In the end, the main results were put into a broader context (CHAPTER VI), discussing the general feasibility of reforestations both in ecological terms as well as in terms of carbon trade mechanisms. A short example highlights the strong connection between the feasibility of reforestations and the global carbon market. Finally, open research questions are brought forth revealing the yet large research potential of Central Asian Desert ecosystems in general and in terms of carbon sequestration.
Inflammation is an adaptive response that is triggered by noxious stimuli and conditions, such as infection and tissue injury. Neutrophils, eosinophils, monocytes, tissue macrophages and dendritic cells can all ingest bacteria, tissues debris and apoptotic cells after injury or infection. These cells derived from bone marrow progenitors, circulate in the blood and migrate to peripheral tissues. Macrophages produce and secrete a cascade of pro-inflammatory and anti-inflammatory cytokines, such as interleukin-6 (IL-6), IL-10, and IL-12 that are trafficked and secreted by constitutive exocytosis. IL-10 and IL-6 are known to be rapidly induced during infection and / or injury, which make them possible mediators of early phagocyte recruitment. This thesis work aimed at detailed investigation of role of these cytokines in peritoneal inflammation. Under normal physiological conditions peritoneal cavity of normal BALB/c mice contains mainly CD45+ lymphocytes and CD11b+ myeloid cells with typical macrophage phenotype. The resident peritoneal cells play an important role in organismal homeostasis by taking part in innate and adaptive immunity. To explore this in detail, the physiological properties of peritoneal resident macrophage populations were studied under steady state and during inflammation conditions. Upon rapid induction of sterile inflammation by thioglycollate or lipopolysaccharide, the resident peritoneal cells could no longer be recovered in a peritoneal wash 6h after treatment. During ceacal content (CC) peritonitis, these cells were lost even more rapidly. Neutrophils, monocytes and lymphocytes replace the resident peritoneal phagocyte populations. During sepsis the absence of peritoneal macrophages decreases neutrophils recruitment to the inflammatory site and subsequently increases sepsis. Upon peritoneal wash cell transfer, total peritoneal cells could be recovered from the peritoneum of non infected mice, whereas these cells disappeared after CC infection in mice. The fate of resident peritoneal cells and their migration into lymphoid organs such as omentum and parathymic lymph nodes was further studied following induction of peritoneal infection. The CC infection induced lost cells from peritoneum were emigrated into omentum and parathymic lymph nodes but not in mesenteric lymph nodes. R1 cells were mostly observed in parathymic lymph nodes after 72h of infection but not after 1h, whereas, R2 cells were selectively observed in omentum just 1h after infection and 72h as well. These results were further confirmed by adoptive transfer showing emigration of R2 cells into omentum 1h after infection. Additionally, analysis of cytokine production after CC peritonitis showed early production of IL-10 and IL-6, which is in agreement with earlier findings and further supports the importance of these cytokines in phagocyte recruitment. The role of IL-10, IL-6 and other cytokines as possible mediators of early inflammation and in the recruitment of monocytes, neutrophils or eosinophils to the peritoneum during inflammation was determined by cytokine application. The intraperitoneal application of IL-10 recruited monocytes, neutrophils, T cells, B cells and eosinophils to the peritoneum. However, IL-10 knockout mice showed even increased recruitment of leucocytes to the peritoneal cavity in CC infection suggesting their IL-10 independent recruitment with the exception of eosinophils. Even though eosinophils are effector cells which are recruited to the site of inflammation; during homeostasis eosinophils constitute an abundant leukocyte population in the gastrointestinal tract. Therefore, possible role of eosinophils in bacterial infection was further studied using Δdbl GATA mice which lack mature eosinophils. In the absence of eosinophils, the monocyte and neutrophil recruitment was unaffected after CC infection, while there was increased T and B cell recruitment at the same time. The Δdbl GATA mice also showed reduced production of IL-4, 18h after infection. The eosinophils secrete IL 4 which may induce alternative macrophage activation. These results together with cytokine administration and IL-10 ko mouse data suggest a novel and major role of IL-10 in attracting and in recruiting eosinophils after peritoneal infection. Altogether, present thesis work demonstrates a new aspect of IL-10 interaction with eosinophils in mouse peritoneal environment during peritonitis. It gives a new insight for understanding the possible role of eosinophils in modulating the peritoneal environment in resolution of bacterial infection and can be useful in designing new approaches for therapeutic strategies in combating sepsis and peritoneal inflammation.