The human epidermal growth factor receptor (HER-2) is over-expressed in 20-30% of breast carcinomas and is a prognostic marker for poor patient outcome. We previously identified the transcription/translation factor Y-box binding protein-1 (YB-1) to be a novel substrate of AKT which binds to epidermal growth factor receptor (EGFR) and HER-2 promoters once phosphorylated (Wu J et al. 2006). YB-1 is over-expressed in approximately 40% of breast cancers; its expression is strongly correlated with HER-2 and is associated with poor patient survival. In order to gain a deeper understanding of the functional role of YB-1 in HER-2 over-expressing breast cancer, we silenced the expression of this factor in BT474-m1 and MDA-MB-453 cells. The loss of YB-1 inhibited the growth of BT474-m1 and MDA-MB-453 cells in monolayer and/or in soft agar. Consistent with this, we found a decrease in the expression of YB-1 responsive gene egfr and/or her-2 in BT474-m1 and MDA-MB-453 cells, which could begin to explain how growth is promoted by this factor. Furthermore, loss of YB-1 expression induced apoptosis in BT474-m1 cells. Beyond its role in tumor growth, YB-1 is also strongly linked to drug resistance. We therefore addressed whether it could play a part in Herceptin sensitivity. Herceptin is currently being used to treat patients with HER-2 positive breast cancer; however, only 30% of the patients respond to the therapy and many of them develop resistance within the first year of treatment. Therefore, it is of utmost importance to understand the biology of HER-2 over-expressing breast cancer to develop novel therapies that can benefit more patients. First we established that Herceptin inhibited BT474-m1 cell growth in anchorage-independent conditions whereas MDA-MB-453 cells were resistant to this treatment. We subsequently demonstrated that knock-down of YB-1 increased sensitivity of BT474-m1 cells to Herceptin while MDA-MB-453 cells failed to respond to the combination treatment. The mechanism for Herceptin resistance in MDA-MB-453 cells still remains elusive and requires further investigation. Thus far, we conclude that YB-1 is needed for the growth and survival of HER-2 positive BT474-m1 and MDA-MB-453 breast cancer cells by inducing members of the HER family. / Medicine, Faculty of / Medicine, Department of / Experimental Medicine, Division of / Graduate

Occasionally, a part of the budget of a city, company or other entity has to be allocated among its parts in the form of subsidies or other contributions. The main objective of such an entity is to find such a set of criteria and such a set of their relative weights that estimate the expected cost best. The objective of a sub-entity is subsidy maximization by influencing the criteria and their weights. From this reason, the best budget splitting is a relative term. From the mathematical point of view, such a problem belongs to mathematical optimization or mathematical programming. In this thesis, five quantitative methods are presented. Two of them set the weights without the participation of decision makers. The first allocation method is based on multiple-criteria decision-making and the second one on data envelopment analysis. Together with them, a different mathematical model with maximum and minimum weights for the set of criteria is presented. Two its modifications are discussed too. As the only one presented multi-criteria mathematical model is based on maximization of the relative and absolute profit simultaneously. The aim of this work is to study the known mathematical models for subsidy allocation problem, to invent new ones, to choose suitable ones and subsequently to implement the suitable ones into a standalone GUI application created in the Matlab environment. The presented application proposes several allocation possibilities according to different selected models using mathematical functions taken from Matlab. This user-friendly application is executable on common computers and can be used at the Magistrate of the City of Prague as a support tool in voting decision. Moreover, this application can be extended to new methods or program functions. The selected quantitative methods are used for the budget allocation problem among the city districts for real data of the City of Prague. Experimental results are discussed.

No description available.

Cancer, which is characterised by aggressiveness and increased capacity for metastatic spread still requires basic researchers and clinicians to direct enormous efforts toward the development of novel therapeutic targets. Potential novel targets can be identified and exploited in combination with currently existing therapeutic approaches to improve their efficacy and overcome treatment resistance of tumour cells, protecting the patient from recurrence. To achieve this, different strategies and techniques can be proposed to identify the most promising candidate molecules for further exploitation as therapeutic targets. Human epidermal growth factor receptors (HERs) and NF-E2-related factor 2 (NRF2) are regulators of cellular proliferation and determinants of cancer initiation and progression. NRF2 and HERs confer cancers with resistance to several therapeutic agents. Nevertheless, there is limited understanding of the regulation of HER expression and activation, and the link between NRF2 and HER signalling pathways. This research has demonstrated that pharmacological activation of NRF2 by tert-butyl hydroquinone (tBHQ) upregulates the expression of HER family receptors, HER1 and HER4, elevates phospho protein kinase B (pAKT) levels, and enhances the proliferation of ovarian cancer cells. Pharmacological inhibition using retinoic acid (RA) and bexarotene and genetic inhibition using small interfering RNA (siRNA), did the opposite. Further, tBHQ caused transcriptional induction of HER1 and HER4 with different levels of expression, while siRNA-mediated knockdown of NRF2 prevented this and further caused transcriptional repression. A panel of potent NRF2 inhibitors were screened with the hope of finding the most potent for further investigation. Bexarotene was found to be the most potent and was used either alone, or in combination with lapatinib or erlotinib. The use of these drugs in combination with bexarotene resulted in the repression of HER1, HER2, HER3 and HER4 expression, inhibition of NRF2, elevation of ROS, depletion of glutathione and enhanced cytotoxicity in PEO1, OVCAR3, SKOV3 and MCF7-AREc32 cell lines. This explained the crosstalk mechanism between HER receptor family and NRF2 and the role of NRF2 in drug resistance and as a relevant anti-cancer target which opens up novel avenues of targeting HER receptor kinase family and NRF2 pathways for improving cancer therapy.

Ziel dieser Studie war es, die Häufigkeit der Expression von EGFR, HER-2 sowie COX-2 im Zervixkarzinom zu eruieren. Dabei galt es herauszufinden, ob Unterschiede hinsichtlich des Nachweises dieser drei, möglicherweise therapeutisch relevanten Moleküle zwischen den primären, nicht vortherapierten und operierten Karzinomen und den multimodal vorbehandelten Rezidiven gab. In der vorliegenden retrospektiven Arbeit wurden 45 TMMR-operierte Primärtumoren und 28 LEER-operierte Rezidivtumoren der Universitätsfrauenklinik Leipzig (Triersches Institut) einbezogen und zusätzlich hinsichtlich der prognostischen Überlebensanalyse durch das Tumorstadium, Lymphknotenmetastasen und Rezidivauftreten sowie histologischer Charakteristika untersucht. Dazu wurden Tissue - Microarrays angefertigt mit anschließender immunhistochemischer Untersuchung dieser. Die Ergebnisse zeigten, dass die TMMR-Operation die Überlebensprognose signifikant verbessert, denn lediglich bei den LEER-therapierten Rezidivtumoren erlitten die Patientinnen sowohl Fernmetastasen als auch erneute Rezidive. Weder die Expression der drei untersuchten Moleküle noch die histopathologischen Parameter haben eine prognostische Relevanz. Es gibt keine signifikanten Zusammenhänge zwischen der Häufigkeit der Expression von EGFR, HER-2 sowie COX-2 und Primär-, bzw. Rezidivtumoren, sodass diese Moleküle keine Targets für eine individualisierte, zielgerichtete Therapie beim Zervixkarzinom darstellen.

No description available.

Magnesium (Mg) is the lightest of all structural metals and has tremendous potential for applications in the lightweight industry. However, the corrosion of Mg is a significant barrier towards its wider use. Despite years of research, the fundamental understanding of Mg corrosion still remains short. The enhanced hydrogen evolution reaction (HER) with anodic polarization, the modeling of galvanic corrosion and the impact of hydrogen bubbles for galvanically coupled Mg are important aspects of Mg corrosion that need to be understood before any mitigation measures can be taken. The results presented in this work provide a key step in that direction. In the first part of the project, we explored how the kinetics of reactions involved in the Mg corrosion was influenced by surface changes. A significant difference in Tafel kinetics between a polished Mg surface and a pre-corroded Mg surface was seen. It was also shown that when the concurrent Mg dissolution was accounted for during the cathodic polarization, the absolute value of Tafel slope decreased by a factor of ~2. The enhanced HER on Mg during high anodic dissolution rate was also investigated. The Mg samples were first pre-corroded at different rates until entire Mg surface was corroded. It was found that the surface roughness decreased with an increased rate of corrosion and therefore did not have any influence in enhancing HER at the Mg surface during the anodic dissolution. In order to observe the catalytic effect of anodic dissolution, the potential was immediately dropped to a constant cathodic potential following the pre-corrosion and the current was observed with the time. A peak current, proportional to the prior dissolution rate, was observed. At longer times, the current decayed and converged to similar values irrespective of the prior pre-corrosion rate providing a strong evidence that the enhanced HER is caused due to the catalytic effect provided by the anodic dissolution. Our results provide new mechanistic insights into the current understanding of enhanced HER.In the second part of the project, a numerical simulation was developed to predict the galvanic corrosion rates of Mg coupled to steel. The simulation showed that the kinetics of HER estimated from the cathodic polarization (where significant anodic dissolution rates were absent) underpredicted the experimental HER rates by two orders of magnitude signifying the catalytic effect of anodic dissolution. The simulation allowed us to independently fit the HER kinetics. The simulation also predicted the galvanic current densities and the corrosion potential within 14% error which is a significant improvement of model precision reported previously for galvanic corrosion of Mg corrosion. For the first time, the influence of HER during galvanic corrosion of Mg was reported. Despite substantial hydrogen evolution observed during the experiment, the influence of hydrogen evolution was found to be only 8-9%.

Submitted by PPG Filosofia (filosofia-pg@pucrs.br) on 2018-04-16T17:04:31Z No. of bitstreams: 1 TESE.ALINE ISAIA SPLETTST?SSER.pdf.pdf: 1817826 bytes, checksum: 68144585b7edc10864367eadb8de9af6 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2018-05-03T18:45:07Z (GMT) No. of bitstreams: 1 TESE.ALINE ISAIA SPLETTST?SSER.pdf.pdf: 1817826 bytes, checksum: 68144585b7edc10864367eadb8de9af6 (MD5) / Made available in DSpace on 2018-05-03T18:47:47Z (GMT). No. of bitstreams: 1 TESE.ALINE ISAIA SPLETTST?SSER.pdf.pdf: 1817826 bytes, checksum: 68144585b7edc10864367eadb8de9af6 (MD5) Previous issue date: 2018-03-09 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Our research introduces a critical reflection on the epistemological studies about the nature of wisdom, pointing out gaps in current contemporary theories. We observe the same bibliographical root in all the analyzed works, making the reference to a dichotomous Aristotelian wisdom hinder the incorporation of a concept with both theoretical and practical properties of this knowledge. Another relevant question is the signalization of wisdom as a meta-cognitive virtue, which would denote incorporating, together with new theories, a way of establishing an analytical project associated with ethical presuppositions. We find, in Heraclitus's philosophy, a wisdom of epistemic- ethical imbrication, evidenced even as an instrumental good. From these peculiarities, we selected and interpreted 37 fragments of Heraclitus' work that allowed us to establish new criteria as guides of an integral and dynamic wisdom. From this perspective, we proposed the Founding Theory of Wisdom (FTW), establishing four necessary conditions, or basic principles, to obtain and re-actualize human wisdom, considering that S is wise only if: (i) S is aware of human nature, and motivated to constantly overcome ignorance; (ii) S is committed to an innovative knowledge (at a time t, and in relation to the available resources to access this knowledge); (iii) S masters their cognitive activity through the process of critical understanding; (iv) S structures their intellectual virtues through intellectual sensitivity (IS), and adjusts their moral virtues through harmonious moral guidance (HMG), taking place in its distinctive character. / Nossa pesquisa introduz uma reflex?o cr?tica sobre os estudos epistemol?gicos acerca da natureza da sabedoria, apontando lacunas nas teorias contempor?neas vigentes. Observamos, na totalidade dos trabalhos analisados, a mesma raiz bibliogr?fica, fazendo com que a refer?ncia a uma sabedoria aristot?lica dicot?mica dificulte a incorpora??o de um conceito com propriedades tanto te?ricas quanto pr?ticas desse saber. Outra quest?o relevante ? a sinaliza??o da sabedoria como uma virtude meta-cognitiva, o que denotaria incorporar, junto a novas teorias, uma forma de estabelecer um projeto anal?tico associado a pressupostos ?ticos. Encontramos, na filosofia de Her?clito, uma sabedoria de imbricamento epist?mico-?tico, e evidenciada, inclusive, como bem instrumental. A partir dessas peculiaridades, selecionamos e interpretamos 37 fragmentos da obra heracl?tica que permitiram estabelecer novos crit?rios como orientadores de uma sabedoria integral e din?mica. A partir dessa perspectiva, propomos a elabora??o da Teoria Fundante da Sabedoria (TFS), instituindo quatro condi??es necess?rias, ou princ?pios basilares, para a obten??o e reatualiza??o da sabedoria humana, considerando que S ? s?bio somente se: (i) S ? consciente da natureza humana, e motivado a superar constantemente a ignor?ncia; (ii) S ? comprometido com um conhecimento inovador (em um tempo t, e em rela??o aos recursos dispon?veis de acesso a esse conhecimento); (iii) S domina sua atividade cognitiva atrav?s do processo de entendimento cr?tico; (iv) S estrutura suas virtudes intelectuais atrav?s da sensibilidade intelectual (SI), e ajusta suas virtudes morais, atrav?s da orienta??o moral harm?nica (OMH), realizando-se em seu car?ter distintivo.

<p>To further develop cancer therapy, targeted delivery of cell killing agents directly to tumor cells is an interesting approach. This thesis describes the development of PEG-stabilized liposome conjugates targeting either epidermal growth factor receptor (EGFR) using its natural ligand EGF, or human epidermal growth factor receptor 2 (HER-2) using the antibody trastuzumab. Both receptors are known to be overexpressed on a variety of tumors. The liposomes were loaded with the boronated compounds water soluble boronated acridine (WSA) or water soluble boronated phenantridine (WSP), compounds primarily developed for boron neutron capture therapy, BNCT. </p><p>The liposome conjugates bound specifically to their receptors in cell culture. Because the WSA conjugates exhibited the most favorable boron uptake this compound was chosen for further study. The WSA-loaded liposome conjugates was internalized, an important characteristic for BNCT, and had a long retention inside the cells. The cellular localization of WSA, studied using fluorescence was found to be mainly cytoplasmic. </p><p>To increase the boron uptake studies comparing different incubation methods was performed. It was shown for both EGF and trastuzumab targeted liposomes the uptake could be increased over 10 times by changing from incubation in monolayer culture to incubation in cell suspension in roller flasks. With this treatment the boron concentrations reached after 24 h incubation time was 90 ppm for EGF-liposomes and 132 ppm for trastuzumab-liposomes, levels that are clinically interesting. </p><p>To study the cell-killing efficacy of the liposome-conjugates an experimental BNCT study was performed using EGF-liposome-WSA on cultured glioma cells. About half the number of thermal neutron was needed to inactivate 90% of the cells if the cells had been incubated with EGF-liposome-WSA compared to control cells. When comparing the survival to dose it was shown that to inactivate 90% of the cells 2.9 Gy was needed for EGF-liposome-WSA and neutrons compared to 5.6 Gy with ¹³⁷Cs gamma. </p><p>The biodistribution of EGF-liposomes was also studied in mice. It was compared to EGF and it was found that the addition of a PEG-stabilized liposome to EGF significantly reduced EGF uptake in liver and kidneys, the circulation time in blood was prolonged as well. The reduced liver uptake might be due to inability of the 100 nm liposomes to pass the sinusoidal fenestrations of the liver and bind to the EGFR-rich hepatocytes. The reduced liver uptake potentates the use of EGF-liposome conjugates for systemic injection.</p>

To further develop cancer therapy, targeted delivery of cell killing agents directly to tumor cells is an interesting approach. This thesis describes the development of PEG-stabilized liposome conjugates targeting either epidermal growth factor receptor (EGFR) using its natural ligand EGF, or human epidermal growth factor receptor 2 (HER-2) using the antibody trastuzumab. Both receptors are known to be overexpressed on a variety of tumors. The liposomes were loaded with the boronated compounds water soluble boronated acridine (WSA) or water soluble boronated phenantridine (WSP), compounds primarily developed for boron neutron capture therapy, BNCT. The liposome conjugates bound specifically to their receptors in cell culture. Because the WSA conjugates exhibited the most favorable boron uptake this compound was chosen for further study. The WSA-loaded liposome conjugates was internalized, an important characteristic for BNCT, and had a long retention inside the cells. The cellular localization of WSA, studied using fluorescence was found to be mainly cytoplasmic. To increase the boron uptake studies comparing different incubation methods was performed. It was shown for both EGF and trastuzumab targeted liposomes the uptake could be increased over 10 times by changing from incubation in monolayer culture to incubation in cell suspension in roller flasks. With this treatment the boron concentrations reached after 24 h incubation time was 90 ppm for EGF-liposomes and 132 ppm for trastuzumab-liposomes, levels that are clinically interesting. To study the cell-killing efficacy of the liposome-conjugates an experimental BNCT study was performed using EGF-liposome-WSA on cultured glioma cells. About half the number of thermal neutron was needed to inactivate 90% of the cells if the cells had been incubated with EGF-liposome-WSA compared to control cells. When comparing the survival to dose it was shown that to inactivate 90% of the cells 2.9 Gy was needed for EGF-liposome-WSA and neutrons compared to 5.6 Gy with 137Cs gamma. The biodistribution of EGF-liposomes was also studied in mice. It was compared to EGF and it was found that the addition of a PEG-stabilized liposome to EGF significantly reduced EGF uptake in liver and kidneys, the circulation time in blood was prolonged as well. The reduced liver uptake might be due to inability of the 100 nm liposomes to pass the sinusoidal fenestrations of the liver and bind to the EGFR-rich hepatocytes. The reduced liver uptake potentates the use of EGF-liposome conjugates for systemic injection.