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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.
231

Opposite associations of age-dependent insulin-like growth factor-I standard deviation scores with nutritional state in normal weight and obese subjects

Schneider, Harald Jörn, Saller, Bernhard, Klotsche, Jens, März, Winfried, Erwa, Wolfgang, Wittchen, Hans-Ulrich, Stalla, Günter Karl 01 February 2013 (has links) (PDF)
Objective: Insulin-like growth factor-I (IGF-I) has been suggested to be a prognostic marker for the development of cancer and, more recently, cardiovascular disease. These diseases are closely linked to obesity, but reports of the association of IGF-I with measures of obesity are divergent. In this study, we assessed the association of age-dependent IGF-I standard deviation scores with body mass index (BMI) and intra-abdominal fat accumulation in a large population. Design: A cross-sectional, epidemiological study. Methods: IGF-I levels were measured with an automated chemiluminescence assay system in 6282 patients from the DETECT study. Weight, height, and waist and hip circumference were measured according to the written instructions. Standard deviation scores (SDS), correcting IGF-I levels for age, were calculated and were used for further analyses. Results: An inverse U-shaped association of IGF-I SDS with BMI, waist circumference, and the ratio of waist circumference to height was found. BMI was positively associated with IGF-I SDS in normal weight subjects, and negatively associated in obese subjects. The highest mean IGF-I SDS were seen at a BMI of 22.5–25 kg/m2 in men (+0.08), and at a BMI of 27.5–30 kg/m2 in women (+0.21). Multiple linear regression models, controlling for different diseases, medications and risk conditions, revealed a significant negative association of BMI with IGF-I SDS. BMI contributed most to the additional explained variance to the other health conditions. Conclusions: IGF-I standard deviation scores are decreased in obesity and underweight subjects. These interactions should be taken into account when analyzing the association of IGF-I with diseases and risk conditions.
232

Comparative risk assessment of carcinogens in alcoholic beverages using the margin of exposure approach

Lachenmeier, Dirk W., Przybylski, Maria C., Rehm, Jürgen 06 August 2012 (has links) (PDF)
Alcoholic beverages have been classified as carcinogenic to humans. As alcoholic beverages are multicomponent mixtures containing several carcinogenic compounds, a quantitative approach is necessary to compare the risks. Fifteen known and suspected human carcinogens (acetaldehyde, acrylamide, aflatoxins, arsenic, benzene, cadmium, ethanol, ethyl carbamate, formaldehyde, furan, lead, 4-methylimidazole, N-nitrosodimethylamine, ochratoxin A and safrole) occurring in alcoholic beverages were identified based on monograph reviews by the International Agency for Research on Cancer. The margin of exposure (MOE) approach was used for comparative risk assessment. MOE compares a toxicological threshold with the exposure. MOEs above 10,000 are judged as low priority for risk management action. MOEs were calculated for different drinking scenarios (low risk and heavy drinking) and different levels of contamination for four beverage groups (beer, wine, spirits and unrecorded alcohol). The lowest MOEs were found for ethanol (3.1 for low risk and 0.8 for heavy drinking). Inorganic lead and arsenic have average MOEs between 10 and 300, followed by acetaldehyde, cadmium and ethyl carbamate between 1,000 and 10,000. All other compounds had average MOEs above 10,000 independent of beverage type. Ethanol was identified as the most important carcinogen in alcoholic beverages, with clear dose response. Some other compounds (lead, arsenic, ethyl carbamate, acetaldehyde) may pose risks below thresholds normally tolerated for food contaminants, but from a cost-effectiveness point of view, the focus should be on reducing alcohol consumption in general rather than on mitigative measures for some contaminants that contribute only to a limited extent (if at all) to the total health risk.
233

RNA-binding proteins in yeast mitochondria / RNA-bindende Proteine in Hefemitochondrien

Deumer, Claudia D. 06 December 2002 (has links) (PDF)
This work focused on the further characterisation of Idhp and of the Krebs cycle enzymes citrate synthase 1 (Cit1p) and malate dehydrogenase 1 (Mdh1p) both of which have been identified as RNA-binding proteins without known RNA recognition motifs. Besides analysing their effects on mitochondrial translation and their organisation in protein complexes the work focused on the characterisation of the RNA-binding properties of recombinant Cit1p and Mdh1p: · Cit1p and Mdh1p play no essential role in mitochondrial protein synthesis. · Idhp is in a complex of molecular weight larger than the cytochrome c oxidase (250 kDa). · Cit1p and Mdh1p are in mitochondrial complexes smaller than 250 kDa. · 1000-fold molar excess of tRNA referring to COX2 leader RNA did not inhibit the RNA-binding of Cit1p and Mdh1p. · Cit1p and Mdh1p bind mitochondrial mRNAs (sense and antisense). The influence of cofactors and substrates on RNA-binding was analysed in order to reveal a possible link between the enzymatic function and the property of RNA-binding: · Acetyl-CoA and ATP inhibited the RNA-binding of Cit1p and Mdh1p at a concentration of 5 mM.
234

Engineering of a bifunctional anti-Kv10.1 antibody for cancer therapy / Herstellung und Charakterisierung eines bifunktionalen anti-Kv10.1 Antikörpers für die Krebstherapie

Hartung, Franziska 18 August 2011 (has links)
No description available.
235

An Extremely Rare, Remote Intracerebral Metastasis of Oral Cavity Cancer: A Case Report

Leimert, Mario, Juratli, Tareq A., Lindner, Claudia, Geiger, Kathrin D., Gerber, Johannes, Schackert, Gabriele, Kirsch, Matthias 06 February 2014 (has links) (PDF)
Distant brain metastases from oral squamous cell carcinomas (OSCC) are extremely rare. Here we describe a case of a 53-year-old man with a primary OSCC who referred to the neurosurgical department because of epileptic seizures. MR imaging revealed an enhancing lesion in the right parietal lobe. A craniotomy with tumor removing was performed. Histopathological examination verified an invasive, minimally differentiated metastasis of the primary OSCC. The patient refused whole brain radiation therapy and died from pulmonary metastatic disease 10 months after the neurosurgical intervention without any cerebral recurrence. To the authors’ knowledge, only two similar cases have been previously reported.
236

Serotonin and Melatonin Do Not Play a Prominent Role in the Growth of Prostate Cancer Cell Lines

Pirozhok, Igor, Meye, Axel, Hakenberg, Oliver W., Füssel, Susanne, Wirth, Manfred P. 14 February 2014 (has links) (PDF)
Objectives: To investigate the effects of serotonin and melatonin (MLT) on the regulation of malignant growth and the activity of serotonin receptors (5HTR1a/-1b) in prostate cancer (PCa) cell lines. Materials and Methods: In four PCa cell lines (LNCaP, 22RV1, PC3, DU145) and two reference cell lines 5HTR1a and -1b, relative mRNA expression levels were assessed. Different serotonin and MLT receptor agonists and antagonists were used in stimulation and inhibition experiments. Results: mRNA expression of 5HTR1b was higher than that of 5HTR1a in all PCa cell lines. Serotonin showed a significant growth stimulatory effect in all PCa lines. The 5HTR1a and -1b agonists/antagonists did not significantly affect viability. MLT inhibited viability only in PC3 cells. Similarly, the 5HTR1a antagonist induced apoptotic changes in PC3 cells only at 10–4M, while the 5HTR1b antagonist induced necrosis at 10–4M in all cell lines. Cell cycle alterations were seen in PC3 and DU145 cells under the influence of the 5HTR1a antagonist. Conclusions: Serotonin receptor antagonists and agonists as well as MLT influence viability and apoptosis of PCa cell lines at supraphysiologic concentrations. In contrast to other reports, our results do not support a regulatory role of serotonin or MLT receptor activation or inhibition in PCa growth. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
237

"Es ist, ja, Battlefield – Man(n) kämpft ums Überleben"

Lindner, Anne 21 December 2011 (has links) (PDF)
Wenn das eigene Kind an Krebs erkrankt, werden die Eltern mit massiven organisatorischen und psychosozialen Belastungen konfrontiert. Die Frage nach der Situation der Väter wurde in wissenschaftlichen Untersuchungen dabei bisher vernachlässigt, in aktuellen Fachdiskussionen zeigt sie aber mehr und mehr Präsenz. Ziel dieser Studie ist deshalb, zu erforschen, wie Väter die Krebserkrankung und die damit verbundenen – oft stark veränderten – Lebensumstände erleben. Gleichzeitig liegt der Fokus auf dem (männlichen) Bewältigungsverhalten, woraus schließlich auf mögliche psychosoziale Unterstützungsleistungen geschlossen werden soll. Die Studie stützt sich dabei auf theoretische Grundlagen aus den Themenfeldern „Krebs im Kindes- und Jugendalter“, „Lebenssituation betroffener Familien“, „Väterforschung“ sowie „Bewältigung kritischer Lebensereignisse“. Die Forschungsarbeit umfasst vier Interviews, welche mit der Methode des Problemzentrierten Interviews nach Witzel erhoben wurden. Darunter befinden sich ein Vater, dessen Kind erfolgreich therapiert wurde, zwei Väter, deren Kinder sich seit über zwei Jahren in Behandlung befinden, sowie ein Vater, dessen Kind an der Krebserkrankung verstorben ist. Die Interviews wurden nach der Methode des zirkulären Dekonstruierens von Jaeggi, Faas und Mruck einer Auswertung unterzogen. Die Ergebnisse eröffnen einen vielseitigen Einblick in das Erleben und das Bewältigungsverhalten der interviewten Väter. Neben dem „Kampf“ als zentraler Umgangsform werden verschiedenste Lebensbereiche der Väter deutlich, welche durch die Krebserkrankung des Kindes negativen, aber auch positiven Änderungen unterliegen. Zudem konnten vielfältige Formen (männlicher) Bewältigung erarbeitet werden. Auch Aspekte, die den Bewältigungsprozess fördern bzw. hindern, wurden ersichtlich. Aus den Ergebnissen lässt sich schließen, dass Väter oftmals einer Vielzahl organisatorischer und psychosozialer Belastungen ausgesetzt sind. Spezifische psychosoziale Angebote für Väter eröffnen dabei die Möglichkeit einer gezielten Unterstützung im Bewältigungsprozess. / When their child becomes ill with cancer, parents suddenly have to deal with great organizational and psychosocial burdens. The question of the situation of fathers has been neglected in scientific research for a long time, but present technical discussions give this specific issue more and more weight. The aim of this qualitative study is to research how fathers experience their child‟s cancer and the personal circumstances which are associated with the illness. In addition the focus of the study is on how fathers deal with this critical life event. As a result of the analysis possible methods of psychosocial support shall be worked out. The study is based on theoretical foundations of the topic areas “cancer at the age of childhood and youth”, “life situation of affected families”, “research on fathers” and “theories on how to overcome with critical life events”. The study comprises four interviews with fathers. These interviews were conducted based on the method of problem focused interview from Witzel. The sampling includes one father, whose child was successfully cured, two fathers, whose children are in therapy since more than two years and one father, whose child died of cancer. The interviews were analyzed with the method of circular deconstruction from Jaeggi, Faas and Mruck. The results give a complex insight into how the interviewed fathers experienced the cancer of their child and how they cope with this illness and the resulting personal circumstances. The different areas of life which were changed negatively as well as positively are shown. Furthermore it becomes clear that besides other (male) coping strategies the father`s central way of mastering their fate is by “fighting”. Moreover the results show aspects which promote or stop the coping process. According to the results of this study there are a lot of organizational and psychosocial burdens on fathers who have a child with cancer. Specific psychosocial offers for fathers open up possibilities of a targeted support in the coping process.
238

Prostate Cancer Diagnosis : experimental and Clinical Studies With HRMAS NMR Spectroscopy

Stenman, Katarina January 2011 (has links)
A few abnormal cells found in a small piece of prostate tissue are most consequential for a man’s future. The prevalence of prostate cancer (PCa) is increasing globally. The main instigating factor for this cancer is not yet known, but it appears to be the consequence of many variables such as an increasingly older population, more frequent PSA-testing, and factors involving lifestyle. Prostate cancer screening, as an equivalent for breast cancer screening, has been suggested but unfortunately there are no accurate diagnostic tools available for this type of screening. The reason for this is simply that the prostate is one of the most difficult organs to diagnose and, consequently, PCa screening would generate far too many false-positive and false-negative results.  The prostate is not easily accessible as it is deeply-seated in the male pelvic area, wrapped around the urethra and surrounded by sensitive vital organs.  Furthermore, PCa is frequently multi-focal, and the cancer cells have a tendency of assimilating among normal cells and, thus, do not always form solid lumps.  Therefore, prostate tumors are often not felt by digital rectal examination (DRE) or identified by imaging.  The PSA-test is not reliable as it is more prostate-specific than cancer-specific.  Due to increasing prostate awareness, more early-stage and locally confined PCa are being detected. This is saving lives, although there is a high risk of over treatment and unnecessary side-effects.  The increased detection of PCa requires sophisticated diagnostic methods and highly skilled clinicians who can discern between indolent and aggressive cancers.  The current “gold-standard” for PCa diagnosis is biopsy grading by pathologists using the Gleason score system, which is a difficult task.  Therefore, innovative methods to improve the precision of prostate diagnosis, by increased biopsy sensitivity and tumor localization, are of essence. In light of these difficulties, the metabolomic approach using 1D and 2D high-resolution magic angle spinning (HRMAS) NMR spectroscopy combined with histopathology on intact prostatectomy specimens was evaluated in this research project.  The non-destructive nature of HRMAS NMR enables spectroscopic analysis of intact tissue samples with consecutive histological examinations under light microscope. Metabolomics aids in the unraveling and the discovery of organ-specific endogenous metabolites that have the potential to be reliable indicators of organ function and viability, extrinsic and intrinsic perturbations, as well as valuable markers for treatment response. The results may, therefore, be applied clinically to characterize an organ by utilizing biomarkers that have the capacity to distinguish between disease and health. The aim was to characterize the human and the rat prostate in terms of its intermediary metabolism, which I show here to differ between species and anatomical regions.  Furthermore, the aim is to seek the verification of HRMAS NMR derived metabolites which are known to be a part of the prostate metabolome such as, citrate, choline, and the polyamines which were performed, but also the identification of metabolites not previously identified as part of the local prostate metabolism, such as Omega-6, which was detected in tumors.  The extended aim was to elucidate novel bio-markers with clinical potential. In this study, the common phyto-nutrient, inositol, which appears to possess protective properties, was identified as being a potentially important PCa bio-marker for the distinction between the more indolent Gleason score 6 and the more aggressive Gleason score 7 in non-malignant prostate tissues with tumors elsewhere in the organ. Further studies in this area of PCa research are therefore warranted.
239

In Silico Identification of Novel Cancer Drugs with 3D Interaction Profiling

Salentin, Sebastian 01 August 2018 (has links) (PDF)
Cancer is a leading cause of death worldwide. Development of new cancer drugs is increasingly costly and time-consuming. By exploiting massive amounts of biological data, computational repositioning proposes new uses for old drugs to reduce these development hurdles. A promising approach is the systematic analysis of structural data for identification of shared binding pockets and modes of action. In this thesis, I developed the Protein-Ligand Interaction Profiler (PLIP), which characterizes and indexes protein-ligand interactions to enable comparative analyses and searching in all available structures. Following, I applied PLIP to identify new treatment options in cancer: the heat shock protein Hsp27 confers resistance to drugs in cancer cells and is therefore an attractive target with a postulated drug binding site. Starting from Hsp27, I used PLIP to define an interaction profile to screen all structures from the Protein Data Bank (PDB). The top prediction was experimentally validated in vitro. It inhibits Hsp27 and significantly reduces resistance of multiple myeloma cells against the chemotherapeutic agent bortezomib. Besides computational repositioning, PLIP is used in docking, binding mode analysis, quantification of interactions and many other applications as evidenced by over 12,000 users so far. PLIP is provided to the community online and as open source.
240

Die Palliativversorgung in Deutschland im Spiegel der Gesundheitsökonomie / Health Economic Reflections on Palliative Care in Germany

Plaul, Cornelius 07 March 2018 (has links) (PDF)
Die Palliativversorgung (PV) verfolgt das Ziel, die Lebensqualität in der noch verbleibenden Lebenszeit von Patienten mit lebensbedrohlichen Erkrankungen zu maximieren. Deutschland verfügt mittlerweile über ein umfassendes PV-System im ambulanten und stationären Sektor und einen Anspruch auf PV als Teil der Regelversorgung. Im Rahmen dieser Untersuchung soll überprüft werden, ob die Inanspruchnahme der PV-Institutionen der vom Gesetzgeber und medizinischen Experten intendierten Reihenfolge entspricht und ob es Überlebenszeit- oder Gesundheitsausgabenunterschiede gibt (jeweils im Vergleich zu Nicht-Palliativpatienten). Dazu wird ein Paneldatensatz der AOK PLUS (Sachsen und Thüringen) mit Patienten verwendet, die zwischen 2009 und 2012 an einer Krebserkrankung litten (n=447.191). PV-Patienten werden entsprechend ihres Inanspruchnahmeverhaltens in vier Interventionsgruppen eingeteilt, von denen jeder mittels Propensity Score Matchings eine eigene Kontrollgruppe zugeordnet wird. Als statistische Werkzeuge werden v.a. Übergangswahrscheinlichkeiten, Kaplan-Meier-Überlebensfunktionen sowie lineare und nicht-lineare Regressionsmodelle verwendet. Die Ergebnisse legen nahe, dass die Reihenfolge der Inanspruchnahme im Einklang mit Gesetzen und Richtlinien ist. Überlebensnachteile der PV-Patienten können nicht festgestellt werden. Die Gesundheitsausgaben steigen nach erstmaliger Inanspruchnahme einer PV-Institution in allen Stichproben stark an. Dieses Ergebnis ist sehr robust gegenüber Änderungen der Modellspezifikation, des Modelltyps und der Stichprobe. Die Ergebnisse lassen auf eine hohe Struktur- und Prozessqualität der PV-Angebote schließen. Jedoch führt die Inanspruchnahme von PV in ihrer derzeitigen Form offenbar nicht zu Einsparungen. Ein weiterer Ausbau des PV-Systems finanziert sich demnach nicht „von selbst“. Aufgrund der sehr kurzen Nachbetrachtungszeiträume bleibt die gesundheitsökonomische Analyse der PV weiterhin herausfordernd. / Palliative Care (PC) is an approach for patients with life-threatening diseases that focuses on improving quality of life rather than maximizing the remaining life time. Meanwhile, Germany possesses a comprehensive PC system in the ambulatory and inpatient sector where PC treatments are part of standard care. The objective of this research is to evaluate whether patients are using PC institutions as intended by law and medical experts and whether PC patients differ in terms of survival time or health care expenditures (HCE) in comparison to non-PC patients. For this purpose, a panel data set from the statutory health insurance AOK PLUS (covering the German federal states Thuringia and Saxony) is used, that includes all deceased cancer patients between 2009 and 2012 (n=447,191). According to their usage of PC institutions, PC patients were grouped into four different intervention groups and thus each of them was paired with a control group derived from a propensity score matching. A variety of statistical tools has been used, e.g. transition probabilities, Kaplan-Meier survival functions as well as linear and non-linear regression models. Results show that the intended sequences of PC usage are in accordance with law and medical guidelines. There are no disadvantages in survival of PC patients. In all four samples, HCE of PC patients are higher after the initial contact with a PC institution. This result is very robust against adjustments to the model specification, the model type and the sample. Results suggest that structural and process quality of PC is high. However, no saving effect can be identified for PC in its current form. A further extension of the PC system is therefore not “self-financing”. Due to the very short post treatment time, health economic analysis of PC remains challenging.

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