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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.
41

Optimization of Enantiopure tetrahydro-β-carbolines as Potent Antimalarials and Exploration of salicylic acid analogs for combating multidrug-resistant Neisseria gonorrhoeae

AlMolhim, Hanan Suliman 15 May 2023 (has links)
The emergence of drug resistance towards existing drugs is a constant challenge in the fight against many diseases including Malaria and gonorrhoeae. To evade resistance, new targets must be engaged, and to do that, new structural classes of anti-infective must be prepared and evaluated. During the course of my PhD journey, I had the opportunity to investigate and optimize the antimalarial candidate (±)-2-3b, and salicylic acid (4-1a) as an anti-gonorrhea treatment. Malaria is a life-threatening mosquito-borne disease. In 2021, there were 247 million cases of malaria and the estimated number of malaria deaths stood at 619,000. Because of the rapid development of resistance to all current antimalarials, discovery of antimalarials with unexploited mechanisms of action is critical to reduce malaria mortality. In the Carlier group, our initial approach focused on discovery of inhibitors of the methylerythritol phosphate (MEP) pathway for isoprenoid precursor biosynthesis, since this pathway is essential for Plasmodium falciparum and absent in human. Application of the isopentenyl pyrophosphate (IPP) chemical rescue screen to the compounds of the Malaria Box, a collection of 400 antimalaria candidates with unknown mechanisms of action, identified tetrahydro-β-carboline 2-1 (MMV008138) as an inhibitor of the MEP pathway. Chapter 2 of this work discusses similarity searching of the Novartis portion of the hit set (5K compounds), from the original 20K compound hit set of the Malaria Box, and identifying tetrahydro-β-carboline GNF-Pf-5009, designated as (±)-2-3b. Preparation of pure enantiomers, by resolution, demonstrated the pharmacological superiority of (R)-2-3b over (S)-2-3b, which was found to have good asexual blood stage (ABS) inhibition potency against malarial parasites P. falciparum, and low general cytotoxicity. However, (R)-2-3b was found not orally efficacious in a P. berghei mouse model of malaria. We concluded that the lack of oral efficacy of (R)-2-3b was due to its poor drug-like qualities, in particular its high molecular weight and low solubility. Chapter 3 of this work explores modifications of (R)-2-3b ((R)-3-5Aa) that were expected to improve its properties. We show that the new compounds (R)-3-5Gm and (R)-3-5Gk not only are more potent in vitro than (R)-2-3b ((R)-3-5Aa), but also have molecular weights < 500 g/mol. Neisseria gonorrhoeae is the causative agent of the sexually transmitted disease gonorrhea. Due to the increased rates of infection as well as the prevalence of multidrug-resistant N. gonorrhoeae strains worldwide, the World Health Organization (WHO) and the U.S. Centers for Disease Control and Prevention (CDC) list N. gonorrhoeae at the highest possible threat level to public health. Dual therapy of azithromycin (AZM) and ceftriaxone has been the standard-of-care for treatment of gonococcal infections. However, due to increasing resistance to azithromycin (>33% in some regions) the CDC removed AZM from the treatment regimen for gonorrhea in 2020. Therefore, ceftriaxone remains the only recommended antibiotic for treatment of gonococcal infections. However, increasing resistance to this treatment option has been reported, consequently there is an urgent need to identify novel therapeutics against N. gonorrhoeae. Drug repurposing is a popular strategy that explores new therapeutic opportunities for approved drugs with available information on their pharmacokinetic data, dosages, and toxicity. Salicylic acid is a highly privileged chemical scaffold. Also, the use of salicylic acid to treat sexually transmitted diseases (including gonorrhea) was reported as early as the 19th century. Recently, Dr. Mohamed N. Seleem reported that salicylic acid (4-1a) exhibited modest activity against N. gonorrhoeae strains including the AZM-resistant strain (CDC-181). Chapter 4 of this work illustrates how the anti-gonococcal activity in this scaffold is easily lost by inopportune substitution. However, we found that substituted naphthyl analogs (4-3b,o,p) have superior activity to salicylic acid itself. In addition, the three analogs showed high selectivity, compared to AZM, against N. gonorrhoeae over the vaginal microbiota. / Doctor of Philosophy / In the fight against malaria and gonorrhea, two different diseases, we face one common challenge, which is the emergence of drug resistance towards existing drugs. Therefore, there is a pressing need for new antimalarial and anti-gonorrhea compounds with novel mechanisms of action. This dissertation encompasses my research on the investigation and optimization of the antimalarial candidate (±)-2-3b and Salicylic acid (4-1a) as anti-gonorrhea treatment. Malaria is a life-threatening mosquito-borne disease. It is transmitted through the bites of infected female Anopheles mosquitoes. In 2021, there were 247 million cases of malaria and the estimated number of malaria deaths stood at 619,000. Children under 5 accounted for about 80% of all malaria deaths. In the Carlier group, compound 2-1 (MMV008138) was identified and thoroughly studied as antimalaria candidate. It was found to be effective in killing the malaria parasite, P. falciparum, in red blood cells, in vitro. However, when tested on P. berghei mouse model of malaria, it was found not effective. Chapter 2 of this work discusses the discovery of (±)-2-3b after searching for a structurally similar analog of 2-1. The compound (±)-2-3b can exist in two distinct spatial arrangements (enantiomers) R and S. After preparation of pure enantiomers, we confirmed the pharmacological superiority of (R)-2-3b over (S)-2-3b. The compound (R)-2-3b showed good activity in vitro against malarial parasites P. falciparum, and low general cytotoxicity. However when tested orally on P. berghei mouse model of malaria, it was found not effective. We concluded that the lack of oral efficacy of (R)-2-3b was due to its poor drug-like qualities, such as high molecular weight and low solubility. Chapter 3 of this work explore modifications of (R)-2-3b ((R)-3-5Aa) that will improve its properties. We show that the new compounds (R)-3-5Gm and (R)-3-5Gk not only are more active in vitro than (R)-2-3b ((R)-3-5Aa), but also have lower molecular weights (< 500 g/mol). Neisseria gonorrhoeae is the causative agent of the sexually transmitted disease gonorrhea. The World Health Organization (WHO) and the U.S. Centers for Disease Control and Prevention (CDC) list N. gonorrhoeae at the highest possible threat level to public health because of the increased rates of infection and the appearance of multidrug-resistant N. gonorrhoeae strains worldwide. Dual therapy of azithromycin (AZM) and ceftriaxone has been the standard-of-care for treatment of gonococcal infections. However, due to increasing resistance to azithromycin the CDC removed AZM from the treatment regimen. Therefore, ceftriaxone remains the only recommended antibiotic for treatment of gonococcal infections. However, increasing resistance to this treatment option has been reported. Drug repurposing is a popular strategy that explores new therapeutic opportunities for approved drugs with available information on their pharmacokinetic data, dosages, and toxicity. Salicylic acid is a highly privileged chemical scaffold that has been used to treat sexually transmitted diseases (including gonorrhea) since the 19th century. Chapter 4 of this work illustrates our efforts to enhance the potency of salicylic acid (4- 1a). I performed chemical modifications on (4-1a) and concluded that anti-gonococcal activity is easily lost by inopportune substitution. However, we found that substituted naphthyl analogs (4-3b,o,p) have superior activity to salicylic acid itself. In addition, the three analogs showed high selectivity, compared to AZM, against N. gonorrhoeae over the vaginal microbiota.
42

The common ground workshop, caring for industrial heritage

Adamsone, Darta January 2023 (has links)
Historical hydroelectric stations are part of an aging industrial heritage that is still extremely relevant today through its form of generating energy. Many stations built in the 20th c. are categorized as architectural heritage, therefore protected against demolition or radical change, thus also a radical expansion that would allow to modernize the station and allow for bigger energy output. Viskafors power station in Borås (Sweden) built in 1917 for the former local textile factory,  is a small-scale power station that is marked as architectural heritage, currently owned by Vattenfall.  The town of Viskafors is one of many factory towns along the river and as the industry went bankrupt in the 1970-ties it has become a suburb to the city of Borås. The only public buildings in Viskafors are schools. The town once defined by the industry is now left with an inaccessible waterfront and plenty of unused and unattainable space.The former factory grounds and the restricted area around the hydroelectric station, railway and regional road block the waterfront.The latest station renovation happened in 2013, leaving the second floor and the lift tower empty. Forming another void in the total space that Viskafors has to offer.Can this void be used as leverage to explore the potential of formerly unattainable space within the station and in connection to the waterfront? Keeping this in mind, this thesis aims to find meaningful ways to inhabit and repurpose formerly unattainable space as it is today; to find methods of organizing complex landscapes; initiate a discussion of new thinking of potential hybrid scenarios for the complexities of our future settlements.Can the future be a link to the past and vice versa?The project space stretches from the street level approaching the building to the rooftop, extends into the empty space of the station's second floor, and continues over the other side of the river. The existing second-floor space dimensions are  33 m x 11m x 5.5 m forming a box space. In theory, a box space this size holds infinite potential as long as it remains empty and has no walls, this project aims to explore the method of placing programmed pavilions/interventions as a space-organizing method of work and extending the approach to the rest of the project site area.The aim is to keep the hydroelectric station running while inhabiting the empty space surrounding it, and learning how to live with it.
43

WHAT A WASTE : A dialogue between maker and material towards woven textile sculptures

Taken, Joanne Jasmijn January 2024 (has links)
As soon as a material is viewed as waste, the value of this resource diminishes, leading to a lack of concern for its preservation. By presenting alternative perspectives on such materials, their beauty and potential can be shown. In WHAT A WASTE, new light is shone on discarded fishing ropes from the Swedish seas. The project focuses on the unique qualities of these discarded materials, showcasing their worth despite being worn out. A material-driven approach is employed, wherein the selected materials’ behaviour guides the creation of shape and form. In a dialogue between maker and material, the different characters of the collection take form through a playful and intuitive process. Weaving is the main technique combined with a construction principle in which the unique properties of the discarded ropes lead to shape, colour and texture discoveries. Contemplating utilising an unconventional material in the loom to highlight innovative visual and tactile characteristics. This project proposes new design methods for reusing discarded materials and how people can value waste again through textile design. Exploring ways of working with the ropes, such as detangling, in combination with other yarns can create new aesthetics for three-dimensional woven forms. Aiming to create woven sculptures of varying scales and shapes in a spatial context through a material-led process.
44

Simulation modeling and analysis of device-aware network architectures

Koh, Jin Hou 12 1900 (has links)
Approved for public release; distribution in unlimited. / As the popularity of Internet soars, the content on the Internet is increasingly accessed by mobile devices that are usually small in form factor and limited in resources, in terms of processing capability, bandwidth and battery power. With the changing environment, content providers must serve a large number of access devices with different profiles, while the users have access to a large number of services with different content types. A key challenge in such an environment is how to enable the best possible fit between content and capabilities of a specific access device type. The goal of this thesis research is to explore on the concept of a device-aware network (DAN) that can provide the infrastructure support for device-content compatibility matching to avoid the unnecessary wastage of network and device resources that happens in current device-ignorant networks. A more efficient architecture is proposed which encapsulates device profile information in transmitting packets and incorporates content repurposing functionality in existing network entities, such as routers along the data path. Simulation models are developed to statistically evaluate the performance of the proposed architecture in comparison to existing content repurposing frameworks. The results demonstrated the feasibility and suitability of the architecture, with improvement in network bandwidth conservation. / Civilian, Singapore Defence Science and Technology Agency
45

Drug repurposing and market access : conditions and determinants for price, reimbursement and access of reformulated and repositioned drugs in the United States of America and Europe / Réorientation des médicaments et accès au marché : conditions et déterminants des prix, remboursement et accès des médicaments reformulés et repositionnés aux États-Unis et en Europe

Do Monte Fialho Murteira, Susana Claudia 09 June 2014 (has links)
Le développement de novo de médicaments est un processus long et coûteux. De plus en plus, les développeurs de médicaments cherchent à mettre en oeuvre des stratégies rentables et à moindre risque pour le développement de produits pharmaceutiques. Le processus de trouver de nouveaux usages pour des médicaments existants en dehors de l'indication initiale pour laquelle ils ont été initialement approuvé est couramment désigné comme « repositionnement », « réorientation » ou « reprofilage ». Le développement de formulations différentes pour un même médicament pharmaceutique est communément désigné comme « reformulation » et le processus de trouver une autre utilisation thérapeutique d'un médicament déjà connu est dénommé « repositionnement ». Ces deux stratégies sont devenues un courant dominant dans le développement des médicaments. Les principaux objectifs de la recherche menée dans cette thèse sont de parvenir à proposer une nomenclature et la taxonomie solide et valable pour l'identification et la classification des stratégies de « repurposing » de médicaments ; évaluer les voies de régulation de stratégies de repositionnement et de reformulation, par types de stratégies et dans les 2 régions géographiques étudiées ; et déterminer les paramètres qui ont un impact sur la probabilité d'un résultat positif sur le prix, le remboursement et l'accès au marché vis-à-vis des conditions accordées pour le médicament original dans les deux régions géographiques dans l'étude / De novo drug development is a costly and lengthy process. As a result of such market forces, drug developers are increasingly striving to find cost effective and reduced-risk strategies for developing drug products and to protect existing products from competition, as well as to extend their patent protection time. The process of finding new uses for existing drugs outside the scope of the original indication for which they were initially approved is variously referred as repositioning, redirecting, repurposing, or reprofiling. The development of different formulations for a same pharmaceutical drug is commonly designated as “reformulation” and the process of finding a new therapeutic use for an already known drug is referred to as “repositioning”. Both strategies have become a mainstream in drug development. The main objectives of the research conducted in this thesis are to propose a robust and valid nomenclature and taxonomy for identification and classification of drug repurposing strategies, to evaluate which regulatory pathways and trends are taken by drug repositioning and reformulation, by repurposed types and within the Europe and the US and determine which parameters have the most and least impact on the probability of a successful outcome on pricing, reimbursement and market access in repurposing vis-à-vis the conditions granted for the original drug
46

Développement et applications d’un outil bio-informatique pour la détection de similarités de champs d’interaction moléculaire / Development and applications of a bioinformatic tool to detect molecular interaction field similarities

Chartier, Matthieu January 2016 (has links)
Résumé : Les méthodes de détection de similarités de sites de liaison servent entre autres à la prédiction de fonction et à la prédiction de cibles croisées. Ces méthodes peuvent aider à prévenir les effets secondaires, suggérer le repositionnement de médicament existants, identifier des cibles polypharmacologiques et des remplacements bio-isostériques. La plupart des méthodes utilisent des représentations basées sur les atomes, même si les champs d’interaction moléculaire (MIFs) représentent plus directement ce qui cherche à être identifié. Nous avons développé une méthode bio-informatique, IsoMif, qui détecte les similarités de MIF entre différents sites de liaisons et qui ne nécessite aucun alignement de séquence ou de structure. Sa performance a été comparée à d’autres méthodes avec des bancs d’essais, ce qui n’a jamais été fait pour une méthode basée sur les MIFs. IsoMif performe mieux en moyenne et est plus robuste. Nous avons noté des limites intrinsèques à la méthodologie et d’autres qui proviennent de la nature. L’impact de choix de conception sur la performance est discuté. Nous avons développé une interface en ligne qui permet la détection de similarités entre une protéine et différents ensembles de MIFs précalculés ou à des MIFs choisis par l’utilisateur. Des sessions PyMOL peuvent être téléchargées afin de visualiser les similarités identifiées pour différentes interactions intermoléculaires. Nous avons appliqué IsoMif pour identifier des cibles croisées potentielles de drogues lors d’une analyse à large échelle (5,6 millions de comparaisons). Des simulations d’arrimage moléculaire ont également été effectuées pour les prédictions significatives. L’objectif est de générer des hypothèses de repositionnement et de mécanismes d’effets secondaires observés. Plusieurs exemples sont présentés à cet égard. / Abstract : Methods that detect binding site similarities between proteins serve for the prediction of function and the identification of potential off-targets. These methods can help prevent side-effects, suggest drug repurposing and polypharmacological strategies and suggest bioisosteric replacements. Most methods use atom-based representations despite the fact that molecular interaction fields (MIFs) represents more closely the nature of what is meant to be identified. We developped a computational algorithm, IsoMif, that detects MIF similarities between binding sites. We benchmark IsoMif to other methods which has not been previously done for a MIF-based method. IsoMif performed best in average and more consistently accross datasets. We highlight limitations intrinsic to the methodology or to nature. The impact of design choices on performance is discussed. We built a freely available web interface that allows the detection of similarities between a protein and pre-calculated MIFs or user defined MIFs. PyMOL sessions can be downloaded to visualize similarities for the different intermolecular interactions. IsoMif was applied for a large-scale analysis (5,6 millions of comparisons) to predict offtargets of drugs. Docking simulations of the drugs in the binding site of their top hits were performed. The primary objective is to generate hypotheses that can be further investigated and validated regarding drug repurposing opportunities and side-effect mechanisms.
47

Mitochondrial Disorders Linked to mtDNA instability : From Therapy to Mechanism / Les maladies mitochondriales liées à l’instabilité d’ADN mitochondrial : de la thérapie au mécanisme / Penyakit - penyakit Mitokondria terkait ketidakstabilan mtDNA : dari Terapi Obat menuju Mekanisme Molekuler

Pitayu, Laras 28 September 2015 (has links)
L’instabilité d’ADN mitochondrial (ADNmt) peut être quantitative avec la déplétion de l’ADNmt ou qualitative avec des délétions de l’ADNmt. Ces anomalies sont une des causes les plus commmunes des maladies mitochondriales. Un des gènes qui contrôle la stabilité et le maintien de l’ADNmt est POLG. Ce gène code pour la polymerase gamma mitochondriale. Chez l’homme, les mutations dans le gène POLG sont liées aux maladies mitochondriales telle que; l’insuffisance hépatique, le syndrome d’Alpers, le PEO ou Progressive External Ophtalmoplegia, la neuropathie sensorielle et l’ataxie. Des mutations dans le gène POLG sont aussi associées au syndrome de Parkinson. Aujourd’hui, il n’existe aucune thérapie pour ces maladies. Compte tenu de la conservation évolutive de la fonction mitochondriale de la levure à l’homme, nous avons utilisé deux organismes modèles, Saccharomyces cerevisiae et Caenorhabditis elegans, pour identifier des molecules chimiques capables de compenser l’instabilité de l’ADNmt liée à des mutations du gène POLG dans des fibroblastes d’un patient. Nous avons trouvé trois molécules candidates potentielles: MRS2, MRS3 et MRS4, à partir d’un criblage primaire chez la levure, en utilisant une chimiothèque d’environ 2000 molécules chimiques. MRS3 est la molécule candidate la plus efficace pour la stabilization d’ADNmt chez des mutants POLG de la levure, du champignon filamenteux, du nématode et sur des fibroblastes de patients. MRS3, ou clofilium tosylate (CLO), est un agent antiarrhytmique, médicament pour soigner les troubles du rythme cardiaque. Dans cette étude, nous avons aussi montré que deux autres antiarrhythmiques appartenant à la même classe que CLO avaient un effet positive chez un mutant POLG de C. elegans. En utilisant une approche de chemogénomique chez la levure, nous avons identifié Fis1, un acteur de la fission mitochondriale qui pourrait être impliqué dans la mode d’action de CLO. Fis1 est requise pour la viabilité cellulaire en concentration légèrement toxique de CLO et nécesaire pour la stabilization de l’ADNmt par CLO. L’ensemble de ces résultats ont montré que CLO pourrait être la première molécule chimique qui stimule la réplication de l’ADNmt et qui pourrait être développée pour le traitement des maladies liées à des mutations dans le gène POLG. Ces résultats ont aussi permis de mettre en évidence une nouvelle connexion entre replication de l’ADNmt et la fission mitochondriale. / The instability of mitochondrial DNA (mtDNA) in form of mtDNA depletion (quantitative instability) or large deletion (qualitative instability) is one of the most common cause of mitochondrial diseases.. One of the genes responsible for human mtDNA stability, POLG, is exploited in this study. POLG encodes the human mitochondrial polymerase gamma. In human, POLG mutations are a major cause of mitochondrial disorders including hepatic insufficiency; Alpers syndrome, progressive external ophthalmoplegia, sensory neuropathy and ataxia. They are also associated with Parkinsonism. Currently, there is no effective and disease-specific therapy for these diseases. Based on the conservation of mitochondrial function from yeast to human, we used Saccharomyces cerevisiae and Caenorhabditis elegans as first pass filters to identify chemical compounds that suppresses mtDNA instability in cultured fibroblasts of a POLG-deficient patient. We found three potential candidates, MRS2, MRS3 and MRS4, from a chemical screening of nearly 2000 compounds in yeast. MRS3 is the most efficacious in stabilizing mtDNA in yeast, filamentous fungi, worm and patient fibroblasts. This unsuspected compound, clofilium tosylate (CLO), belongs to a class of antiarrhythmic agents for cardiovascular disease. Two other antiarrhythmic agents (FDA-approved) sharing common pharmacological properties and chemical structure with CLO also show potential benefit for POLG deficiency in C. elegans. Using a chemogenomic approach in yeast, we also discovered that a mitochondrial fission actor Fis1 is implicated in the mechanism of action of CLO. Fis1 is important for cellular viability in a slightly toxic concentration of CLO and is required for the mtDNA stabilizing potency of CLO. Our findings provide evidence of the first mtDNA-stabilizing compound that may be an effective pharmacological alternative for the treatment of POLG-related diseases and uncover a new connection between the mitochondrial fission process and mtDNA replication. / Ketidakstabilan DNA mitokondria (mtDNA) dalam bentuk pengurangan kopi mtDNA di dalam sel (ketidakstabilan kuantitatif), atau pun dalam bentuk delesi pada sekuens mtDNA (ketidakstabilan kualitatif) merupakan salah satu penyebab penyakit mitokondria. Salah satu gen yang bertanggung jawab dalam menjamin kestabilan mtDNA adalah POLG. Gen POLG mengkode protein polimerase gamma pada manusia, yang mereplikasi dan mereparasi mtDNA di dalam mitokondria. Mutasi pada gen POLG dapat menyebabkan penyakit kelainan mitokondria pada manusia, seperti gagal ginjal, sindrom Alpers, Progressive External Ophtalmoplegia, neuropati sensorial, ataxia dan bisa dikaitkan dalam beberapa gejala Parkinsonisme. Saat ini, belum ada terapi obat yang dapat mengatasi penyakit – penyakit tersebut. Berdasarkan kesamaan evolutif dari ragi hingga manusia, pada studi ini kami menggunakan Saccharomyces cerevisiae dan Caenorhabditis elegans untuk mengidentifikasi molekul obat yang berpotensi mengatasi ketidakstabilan mtDNA dari fibroblas pasien manusia yang memiliki mutasi gen POLG. Kami mengidentifikasi tiga kandidat potensial, yakni MRS2, MRS3 dan MRS4 dari penapisan kurang lebih 2000 molekul obat dengan menggunakan ragi. MRS3 adalah kandidat yang paling berkhasiat dan mampu mengatasi ketidakstabilan mtDNA pada ragi, Podospora, cacing dan fibroblas manusia. MRS3 adalah alias bagi clofilium tosylate (CLO), sebuah molekul antiaritmia untuk penyakit kardiovaskuler. Pada studi ini, kami juga menguji aktifitas dua molekul antiaritmia lain yang tergabung dalam kelas yang sama dengan CLO, dan menemukan bahwa kedua molekul ini juga berpotensi mengatasi defisit POLG pada cacing C. elegans. Dengan menggunakan metode kemogenomik pada ragi, kami juga mengidentifikasi sebuah aktor prosesus pembelahan mitokondria, Fis1, yang berpotensi terlibat dalam mekanisme seluler CLO. Fis1 dibutuhkan untuk: (1) kelangsungan hidup ragi pada konsentrasi toksik CLO dan (2) efek CLO dalam menstabilkan mtDNA pada ragi. Keseluruhan studi ini membuktikan potensi CLO sebagai molekul penstabil mtDNA yang pertama, yang dapat dikembangkan sebagai salah satu alternatif terapi obat untuk penyakit – penyakit mitokondria terkait mutasi POLG. Melalui studi ini, juga diungkap adanya hubungan antara kestabilan mtDNA dan prosesus pembelahan mitokondria.
48

Μέθοδοι βιοπληροφορικής για τον επαναπροσδιορισμό φαρμάκων στη νόσο Αλτσχάιμερ

Σιαβέλης, Ιωάννης 04 May 2015 (has links)
Η νόσος Αλτσχάιμερ καταλαμβάνει την πρωτοκαθεδρία στις μη αναστρέψιμες άνοιες με τους επιδημιολογικούς της δείκτες να αυξάνονται όσο μεγαλώνει το προσδόκιμο ζωής του ανθρώπου. Η χρήση φαρμάκων, με αρχική στόχευση άλλη πάθηση, στη νόσο Αλτσχάιμερ αποκαλείται φαρμακευτικός επαναπροσδιορισμός και προσφέρει σαφή πλεονεκτήματα στην ασφάλεια, την ταχύτητα και το κόστος ανάπτυξης μίας εν δυνάμει θεραπείας, ιδιαίτερα όταν η μέχρι σήμερα αντιμετώπιση της πάθησης περιορίζεται στην καθυστέρηση εξέλιξης της βλάβης και τις δευτερογενείς εκδηλώσεις. Στην παρούσα εργασία, εκμεταλλευτήκαμε εργαλεία φαρμακευτικής επαναστόχευσης που βασίζονται στις γονιδιακές υπογραφές πέντε μελετών μικροσυστοιχιών της νόσου Αλτσχάιμερ. Καίριο στάδιο στη συγκρότηση γονιδιακών υπογραφών είναι ο προσδιορισμός της διαφορικής έκφρασης των γονιδίων. Εφαρμόζοντας τρεις διαφορετικές τεχνικές (Limma, ChDir, mAP-KL) για το σκοπό αυτό και τοποθετώντας τα αποτέλεσματα σε τέσσερα ξεχωριστά εργαλεία φαρμακευτικής επαναστόχευσης (cMap, SPIEDw, sscMap, LINCS-L1000), αναδείξαμε φάρμακα που συστηματικά αντιστρατεύονται τη νόσο. Η περαιτέρω ανάλυση σε επίπεδο χημικής δομής, λειτουργικών μονοπατιών και δικτυακής θεώρησης προσδιόρισε το μηχανισμό δράσης των φαρμάκων και πρότεινε νέα βιοδραστικά μόρια ως δυνατικές θεραπευτικές επιλογές. / Alzheimer’s disease dominates dementias of irreversible cause with alarming epidemiologic characteristics due to rise of human life expectancy. The use of initially otherwise purposed drugs in Alzheimer is described as drug repositioning and offers clear advantages in terms of safety, speed and cost issues in the development of a potential therapy, particularly when current treatments are limitited to symptoms’ delay and secondary comorbidities. In this study, we exploited drug repurposing tools based on gene signatures from five microarray experiments of Alzheimer’s disease. A fundamental step in constructing gene signatures is to define differential gene expression. For this purpose, we used three different methods (Limma, ChDir, mAP-KL) which we analyzed with four distinct drug repurposing tools (cMap, SPIEDw, sscMap, LINCS-L1000) and found drugs that systematically reverse the disease signature. Further processing of the results with regard to chemical structure, pathway and network analysis revealed the mode of the drugs’ actions and highlighted them as potential therapeutic choices for Alzheimer’s disease.
49

Exploring EV Battery Secondary Life Business models and Reverse Logistic perspectives

Vu, Felix, Rahic, Melanie January 2019 (has links)
In connection to the increasing awareness of vehicles and its impact on the environment, the interest in the electric vehicle market has shown a significant growth in the recent years. According to forecasts, it is also projected to increase further in the future. These electric vehicles are driven by lithium-ion batteries with an expected service life of 5-15 years depending on different technology generations and design concepts. After the given service life, the battery has lost approximately 20 percent of its capacity and is no longer permitted to be used in its original application area again, out of safety reasons. Although the retired battery pack is not suitable for vehicles, its remaining capacity can still be utilized in other applications. Hence, the term second life has become a common subject in the automotive industry, where companies are trying to find new application areas for the retired electric vehicle battery packs. Common methods regarding second life of electric vehicle batteries are processes such as remanufacturing, repurposing and re-use. These presented second life methods are from a reverse logistics perspective. Second life alternatives enable a better sustainability and reduces the environmental impact by re-using and recycling existing materials.   In this thesis, the authors examined different second life concepts with the same prerequisite, an electric vehicle lithium-ion battery pack with an energy capacity of 20 kWh. The project has been conducted in a company that is one of the leading manufacturers in the heavy-duty industrial vehicle industry, which currently is developing their electric vehicle machines. Several different concepts have been generated and analysed to find the most applicable business model concepts from a second life perspective. The purpose has been to investigate and calculate which of these business model concepts are most feasible from an economic and a reverse logistics perspective. In order to fulfil the purpose, the following research questions have been formulated:   RQ1: Which secondary use business model concepts are feasible for battery packs of electrified machines? RQ2: Out of the above identified concepts, which business model concept is economically feasible and how can its reverse logistic be composed?   In order to answer the research questions, the authors have analysed different cost aspects and forecasts based on existing research and case company data. This is performed to develop the most profitable concepts based on the collected data, where the generated ideas concluded in three final concepts. For these concepts, individual business model canvases were created to illustrate all important parts of the concepts. The thesis resulted in an economic analysis of the three concepts, visualizing function diagrams and comparing them to each other, to identify the most applicable concept for the case company. The remanufacturing concept proved to be the most applicable one, where its associated reverse logistics and recycling process were investigated and determined. In conclusion the thesis can firstly contribute to future research by the created process map that companies can use and apply in their second life process, correlated to the managerial implications. Secondly, the remanufacturing concept can be a potential future investment for the case company, considering all valuable factors that have been analysed throughout the thesis.     Keywords: Battery pack, Battery secondary use, Business model, Reverse logistic, ESS, Remanufacturing, Battery repurposing, re-use, Battery second life economic analysis.
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Užití biodegradabilních polymerních konjugátů s vysokou molekulovou hmotností k účinnému/ doručení cytostatických léčiv do solidních nádorů. / Biodegradable high molecular weight polymeric conjugates for efficient delivery of cytostatic drugs into solid tumors.

Černý, Viktor January 2015 (has links)
Cancer remains one of the most pressing issues of contemporary science and medicine. Incidence of malignant diseases is rising worldwide and they represent a major problem for the society due to both economic and ethical issues they cause. Although the progress in cancer biology, therapy and immunology has led to the introduction of many novel therapeutic protocols, approaches and drugs with specificity defined on a molecular level into clinical practice, many malignancies retain their poor prognosis. Therefore, intense research into new ways to increase our therapeutic options is warranted. Unfortunately, bringing a completely novel drug into clinical use takes extremely high amounts of time and money and entails a high risk of failure. Therefore, a promising approach has been recently adopted which lies in repurposing compounds already used in human medicine for cancer treatment. This form of research can advance through clinical trials for a new indication much easier, faster and cheaper than researching completely new drugs. The aim of this study was to examine the anticancer potential of one such drug, mebendazole. An anthelminthic from the family of benzimidazoles, mebendazole has been in common clinical use from the 1970s and is marked by its low toxicity as well as its very low solubility....

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