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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Analyzing support of postnatal transition in term infants after c-section

Konstantelos, Dimitrios, Ifflaender, Sascha, Dinger, Jürgen, Burkhardt, Wolfram, Rüdiger, Mario 18 May 2015 (has links)
Background: Whereas good data are available on the resuscitation of infants, little is known regarding support of postnatal transition in low-risk term infants after c-section. The present study was performed to describe current delivery room (DR) management of term infants born by c-section in our institution by analyzing videos that were recorded within a quality assurance program. Methods: DR- management is routinely recorded within a quality assurance program. Cross-sectional study of videos of term infants born by c-section. Videos were analyzed with respect to time point, duration and number of all medical interventions. Study period was between January and December 2012. Results: 186 videos were analyzed. The majority of infants (73%) were without support of postnatal transition. In infants with support of transition, majority of infants received respiratory support, starting in median after 3.4 minutes (range 0.4-14.2) and lasting for 8.8 (1.5-28.5) minutes. Only 33% of infants with support had to be admitted to the NICU, the remaining infants were returned to the mother after a median of 13.5 (8-42) minutes. A great inter- and intra-individual variation with respect to the sequence of interventions was found. Conclusions: The study provides data for an internal quality improvement program and supports the benefit of using routine video recording of DR-management. Furthermore, data can be used for benchmarking with current practice in other centers.
182

Fingolimod in a patient with heart failure on the background of pulmonary arterial hypertension and coronary artery disease

Thomas, Katja, Schrötter, Hagen, Halank, Michael, Ziemssen, Tjalf 18 May 2015 (has links)
Background: Fingolimod is the first oral immunomodulatory therapy approved for highly active relapsing remitting multiple sclerosis. Based on the distribution pattern of fingolimod interacting sphingosine-1-phosphat receptors in organism including immune system and cardiovascular system clinical monitoring of patients and evaluation of adverse events are recommended. Despite extensive data on cardiovascular safety, experience with fingolimod in patients with concomitant cardiological disease, especially within the pulmonary circulation, is rare. Case presentation: We report the case of a 46-year-old woman presented with relapsing remitting multiple sclerosis and severe idiopathic pulmonary arterial hypertension. Fingolimod was initiated because of disease activity of multiple sclerosis with two relapses and gadolinium-enhancing lesions in MRI. The patient demonstrated stable disease course of idiopathic pulmonary arterial hypertension when fingolimod was started. Fingolimod therapy did not alter or even worsen the pulmonary or cardiovascular conditions during first dose application as well as follow up of nine months. Conclusion: In this report, we present the first case of fingolimod treatment in a patient with highly active multiple sclerosis and severe idiopathic pulmonary arterial hypertension. We suggest an interdisciplinary approach with detailed cardiopulmonary monitoring for safety in such patients.
183

Temporary loss of moral behavior in a patient undergoing chemotherapy with cisplatin - breaking bad

Barlinn, Kristian, Lehrbach, Hans, Siepmann, Timo, Brauer, David, Buntrock, Ulrich, Sassim, Norbert 28 July 2015 (has links)
Background: Behavioral disturbances following chemotherapy with cisplatin are rare. Here, we report a patient with temporary loss of moral behavior in the setting of cisplatin-based chemotherapy for treatment of tonsillar cancer. Case presentation: A 66-year-old Caucasian male with no psychiatric or violent history was started on chemotherapy with cisplatin for treatment of tonsillar cancer. During the following weeks, the patient developed profound personality changes involving volatile emotions and impulsive aggression with verbal and physical assaults on others. Admitted to the hospital, the patient lacked any awareness that his behavior was wrong. Chemotherapy was discontinued and the patient was prescribed risperidone. Aside from mild cognitive impairment, comprehensive neuropsychological, neuroradiological and lab testing were unremarkable. Three weeks following cessation of chemotherapy, the patient had recovered to his original mental state and he was completely aware of his wrongdoing and social misconduct. Conclusion: Since neurotoxic effects of chemotherapeutics on the brain are not yet sufficiently elucidated, our case emphasizes that early signs of behavioral abnormalities in patients receiving chemotherapy should trigger comprehensive psychiatric evaluation and ongoing monitoring of the patients’ mental state.
184

Effect of surgical experience on imageless computer-assisted femoral component positioning in hip resurfacing – a preclinical study

Stiehler, Maik, Goronzy, Jens, Kirschner, Stephan, Hartmann, Albrecht, Schäfer, Torsten, Günther, Klaus-Peter 17 July 2015 (has links)
Background: The clinical outcome of hip resurfacing (HR) as a demanding surgical technique associated with a substantial learning curve depends on the position of the femoral component. The aim of the study was to investigate the effects of the level of surgical experience on computer-assisted imageless navigation concerning precision of femoral component positioning, notching, and oversizing rate, as well as operative time. Methods: Three surgeons with different levels of experience in both HR and computer-assisted surgery (CAS) prepared the femoral heads of 54 synthetic femurs using the Durom TM Hip Resurfacing (Zimmer, Warsaw, IN, USA) system. Each surgeon prepared a total of 18 proximal femurs using the Navitrack® system (ORTHOsoft Inc., Montreal, Canada) or the conventional free-hand Durom TM K-wire positioning jig. The differences between planned and postoperative stem shaft angle (SSA) and anteversion angle in standardized x-rays were measured and the operative time, not including the time for calibrating the CAS-system, was documented. Notching was evaluated by the three surgeons in a randomized manner. Oversizing was determined by the difference of the preoperative determined cap and the cap size advised by the CAS-system. Results: CAS significantly reduced the overall mean deviation between planned and postoperative SSA in comparison with the conventional procedure (mean ± SD, 1 ± 1.7° vs. 7.4 ± 4.4°, P <0.01) regardless of the surgeon’s level of experience. The incidence of either varus or valgus SSA deviations exceeding 5° were 1/27 for CAS and 15/27 for the conventional method, respectively (P<0.001), corresponding to a reduction by 97%. Using CAS, the rate of notching was reduced by 100%. Conclusions: The accuracy of femoral HR component orientation is significantly increased by use of CAS regardless of the surgeon’s level of experience in our preclinical study. Thus, imageless computer-assisted navigation can be a valuable tool to improve implant positioning in HR for surgeons at any stage of their learning curve.
185

Role of ALADIN in Human Adrenocortical Cells for Oxidative Stress Response and Steroidogenesis

Jühlen, Ramona, Idkowiak, Jan, Taylor, Angela E., Kind, Barbara, Arlt, Wiebke, Huebner, Angela, Koehler, Katrin 27 July 2015 (has links)
Triple A syndrome is caused by mutations in AAAS encoding the protein ALADIN. We investigated the role of ALADIN in the human adrenocortical cell line NCI-H295R1 by either over-expression or down-regulation of ALADIN. Our findings indicate that AAAS knock-down induces a down-regulation of genes coding for type II microsomal cytochrome P450 hydroxylases CYP17A1 and CYP21A2 and their electron donor enzyme cytochrome P450 oxidoreductase, thereby decreasing biosynthesis of precursor metabolites required for glucocorticoid and androgen production. Furthermore we demonstrate that ALADIN deficiency leads to increased susceptibility to oxidative stress and alteration in redox homeostasis after paraquat treatment. Finally, we show significantly impaired nuclear import of DNA ligase 1, aprataxin and ferritin heavy chain 1 in ALADIN knock-down cells. We conclude that down-regulating ALADIN results in decreased oxidative stress response leading to alteration in steroidogenesis, highlighting our knock-down cell model as an important in-vitro tool for studying the adrenal phenotype in triple A syndrome.
186

The in vivo kinetics of RNA polymerase II elongation during co-transcriptional splicing

Shav-Tal, Yaron, Neufeld, Noa, Bieberstein, Nicole, Causse, Sebastien Z., Böhnlein, Eva-Maria, Neugebauer, Karla M., Darzacq, Xavier 06 January 2016 (has links)
RNA processing events that take place on the transcribed pre-mRNA include capping, splicing, editing, 3′ processing, and polyadenylation. Most of these processes occur co-transcriptionally while the RNA polymerase II (Pol II) enzyme is engaged in transcriptional elongation. How Pol II elongation rates are influenced by splicing is not well understood. We generated a family of inducible gene constructs containing increasing numbers of introns and exons, which were stably integrated in human cells to serve as actively transcribing gene loci. By monitoring the association of the transcription and splicing machineries on these genes in vivo, we showed that only U1 snRNP localized to the intronless gene, consistent with a splicing-independent role for U1 snRNP in transcription. In contrast, all snRNPs accumulated on intron-containing genes, and increasing the number of introns increased the amount of spliceosome components recruited. This indicates that nascent RNA can assemble multiple spliceosomes simultaneously. Kinetic measurements of Pol II elongation in vivo, Pol II ChIP, as well as use of Spliceostatin and Meayamycin splicing inhibitors showed that polymerase elongation rates were uncoupled from ongoing splicing. This study shows that transcription elongation kinetics proceed independently of splicing at the model genes studied here. Surprisingly, retention of polyadenylated mRNA was detected at the transcription site after transcription termination. This suggests that the polymerase is released from chromatin prior to the completion of splicing, and the pre-mRNA is post-transcriptionally processed while still tethered to chromatin near the gene end.
187

Formalizing biomedical concepts from textual definitions

Petrova, Alina, Ma, Yue, Tsatsaronis, George, Kissa, Maria, Distel, Felix, Baader, Franz, Schroeder, Michael 07 January 2016 (has links)
BACKGROUND: Ontologies play a major role in life sciences, enabling a number of applications, from new data integration to knowledge verification. SNOMED CT is a large medical ontology that is formally defined so that it ensures global consistency and support of complex reasoning tasks. Most biomedical ontologies and taxonomies on the other hand define concepts only textually, without the use of logic. Here, we investigate how to automatically generate formal concept definitions from textual ones. We develop a method that uses machine learning in combination with several types of lexical and semantic features and outputs formal definitions that follow the structure of SNOMED CT concept definitions. RESULTS: We evaluate our method on three benchmarks and test both the underlying relation extraction component as well as the overall quality of output concept definitions. In addition, we provide an analysis on the following aspects: (1) How do definitions mined from the Web and literature differ from the ones mined from manually created definitions, e.g., MeSH? (2) How do different feature representations, e.g., the restrictions of relations' domain and range, impact on the generated definition quality?, (3) How do different machine learning algorithms compare to each other for the task of formal definition generation?, and, (4) What is the influence of the learning data size to the task? We discuss all of these settings in detail and show that the suggested approach can achieve success rates of over 90%. In addition, the results show that the choice of corpora, lexical features, learning algorithm and data size do not impact the performance as strongly as semantic types do. Semantic types limit the domain and range of a predicted relation, and as long as relations' domain and range pairs do not overlap, this information is most valuable in formalizing textual definitions. CONCLUSIONS: The analysis presented in this manuscript implies that automated methods can provide a valuable contribution to the formalization of biomedical knowledge, thus paving the way for future applications that go beyond retrieval and into complex reasoning. The method is implemented and accessible to the public from: https://github.com/alifahsyamsiyah/learningDL.
188

Regeneration of Cryoinjury Induced Necrotic Heart Lesions in Zebrafish Is Associated with Epicardial Activation and Cardiomyocyte Proliferation

Weidinger, Gilbert, Schnabel, Kristin, Wu, Chi-Chung, Kurth, Thomas 07 January 2016 (has links)
In mammals, myocardial cell death due to infarction results in scar formation and little regenerative response. In contrast, zebrafish have a high capacity to regenerate the heart after surgical resection of myocardial tissue. However, whether zebrafish can also regenerate lesions caused by cell death has not been tested. Here, we present a simple method for induction of necrotic lesions in the adult zebrafish heart based on cryoinjury. Despite widespread tissue death and loss of cardiomyocytes caused by these lesions, zebrafish display a robust regenerative response, which results in substantial clearing of the necrotic tissue and little scar formation. The cellular mechanisms underlying regeneration appear to be similar to those activated in response to ventricular resection. In particular, the epicardium activates a developmental gene program, proliferates and covers the lesion. Concomitantly, mature uninjured cardiomyocytes become proliferative and invade the lesion. Our injury model will be a useful tool to study the molecular mechanisms of natural heart regeneration in response to necrotic cell death.
189

Formalizing biomedical concepts from textual definitions: Research Article

Tsatsaronis, George, Ma, Yue, Petrova, Alina, Kissa, Maria, Distel, Felix, Baader, Franz, Schroeder, Michael 04 January 2016 (has links)
Background Ontologies play a major role in life sciences, enabling a number of applications, from new data integration to knowledge verification. SNOMED CT is a large medical ontology that is formally defined so that it ensures global consistency and support of complex reasoning tasks. Most biomedical ontologies and taxonomies on the other hand define concepts only textually, without the use of logic. Here, we investigate how to automatically generate formal concept definitions from textual ones. We develop a method that uses machine learning in combination with several types of lexical and semantic features and outputs formal definitions that follow the structure of SNOMED CT concept definitions. Results We evaluate our method on three benchmarks and test both the underlying relation extraction component as well as the overall quality of output concept definitions. In addition, we provide an analysis on the following aspects: (1) How do definitions mined from the Web and literature differ from the ones mined from manually created definitions, e.g., MeSH? (2) How do different feature representations, e.g., the restrictions of relations’ domain and range, impact on the generated definition quality?, (3) How do different machine learning algorithms compare to each other for the task of formal definition generation?, and, (4) What is the influence of the learning data size to the task? We discuss all of these settings in detail and show that the suggested approach can achieve success rates of over 90%. In addition, the results show that the choice of corpora, lexical features, learning algorithm and data size do not impact the performance as strongly as semantic types do. Semantic types limit the domain and range of a predicted relation, and as long as relations’ domain and range pairs do not overlap, this information is most valuable in formalizing textual definitions. Conclusions The analysis presented in this manuscript implies that automated methods can provide a valuable contribution to the formalization of biomedical knowledge, thus paving the way for future applications that go beyond retrieval and into complex reasoning. The method is implemented and accessible to the public from: https://github.com/alifahsyamsiyah/learningDL.
190

Soil Chemical and Microbial Properties in a Mixed Stand of Spruce and Birch in the Ore Mountains (Germany)—A Case Study

Schua, Karoline, Wende, Stefan, Wagner, Sven, Feger, Karl-Heinz 12 February 2016 (has links)
A major argument for incorporating deciduous tree species in coniferous forest stands is their role in the amelioration and stabilisation of biogeochemical cycles. Current forest management strategies in central Europe aim to increase the area of mixed stands. In order to formulate statements about the ecological effects of mixtures, studies at the stand level are necessary. In a mixed stand of Norway spruce (Picea abies (L.) Karst.) and silver birch (Betula pendula Roth) in the Ore Mountains (Saxony, Germany), the effects of these two tree species on chemical and microbial parameters in the topsoil were studied at one site in the form of a case study. Samples were taken from the O layer and A horizon in areas of the stand influenced by either birch, spruce or a mixture of birch and spruce. The microbial biomass, basal respiration, metabolic quotient, pH-value and the C and N contents and stocks were analysed in the horizons Of, Oh and A. Significantly higher contents of microbial N were observed in the Of and Oh horizons in the birch and in the spruce-birch strata than in the stratum containing only spruce. The same was found with respect to pH-values in the Of horizon and basal respiration in the Oh horizon. Compared to the spruce stratum, in the birch and spruce-birch strata, significantly lower values were found for the contents of organic C and total N in the A horizon. The findings of the case study indicated that single birch trees have significant effects on the chemical and microbial topsoil properties in spruce-dominated stands. Therefore, the admixture of birch in spruce stands may distinctly affect nutrient cycling and may also be relevant for soil carbon sequestration. Further studies of these functional aspects are recommended.

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