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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.
1

Expression of PTTG Gene in the Colon-Rectal Carcinoma Cell Line, and the Effect of the Chemotherapeutic Drug 5-FU and Insulin

Hsieh, Cheng-Hsiu 25 June 2006 (has links)
Colorectal cancer (CRC) is the 3rd common cancer in the world. Because the five-year survival rate is below 60 % in the patients with CRC, two important respects in CRC researches are early diagnosis and more effective chemotherapeutic drugs. In fact, the studies on molecular pathology of CRC can resolve these two problems. Insulin has a role in the carcinogenesis and developments of CRC, and 5-FU is a standard chemotherapeutic drug for the patients with stage III CRC. As a human securin, PTTG has a major role in many functions. In our studies of 2-D proteomics, PTTG correlates with the invasiveness of CRC. Besides, it is found to be highly expressed in many types of cancer, but the expression of PTTG is, however, low or undetectable in normal tissues. This character of tumor-specific expression is suitable for drug and target therapy. Therefore, we use cell line HT-29 to study the effects of 5-FU and insulin on the expression of PTTG. We have found that insulin in the physiologic level up-regulates PTTG. In normal physiologic level, insulin up-regulates PTTG, in a dose-dependent manner. On the other hand, the induction of PTTG by insulin more than normal physiologic level is decreased. In the studies with 5-FU, PTTG has a higher level after treatment, but not in dose-dependent manner. The up-regulation of PTTG by 5-FU is decreased in a higher dose. In cancer cells, insulin regulated pathways may contribute to the growth, proliferation, and apoptosis of tumors by activating oncogenic molecular targets such as PTTG. We have showed that insulin of bio-physiologic level can up-regulate PTTG in colon cancer HT-29 cell lines. Induction of PTTG by insulin suggests a mechanism by which insulin may contribute to the development and/or progression of colon cancers. To tumor- specific expression of PTTG, induction of PTTG by insulin, consequently, may be a target of colon cancer treatment. In the studies of 5-FU and PTTG, we have found that 5-FU in HT-29 cells can induce PTTG, with a peak effect in a dose around IC50. Interestingly, the induction of PTTG is decreased in a higher dose of 5-FU. This is a new finding in the effect of 5-FU on PTTG. Accordingly, we can realize why PTTG in some studies is suppressed; the others have a higher level. More importantly, the connection of PTTG expression between sister chromatic separation and DNA repair after DNA damage is more reasonable. Based on this finding, we propose that PTTG connects DNA damage response pathways, sister chromatic separation and apoptosis after DNA damage. Therefore, PTTG has a key role after DNA damage, deciding cells to have DNA repair/cell cycle arrest or to progress to apoptosis.
2

Retrospective Case Series of 15 Patients Treated with Chemoradiation Using 5-FU and Nedaplatin for Gynecological Malignancy: With Regard to Hemotoxicity

ISHIGAKI, TAKEO, NAGANAWA, SHINJI, OKADA, TOHRU, KUBOTA, SEIJI, MURAO, TAKAYUKI, OKUDA, TAKAHITO, ISHIHARA, SHUNICHI, HIRASAWA, NAOKI, IKEDA, MITSURU, ITOH, YOSHIYUKI 02 1900 (has links)
No description available.
3

Long non-coding RNA-based mechanisms for the inhibition of cell growth and development by 5 - Fluorouracil / Mécanismes à base de ARNlnc pour l'inhibition de la croissance cellulaire et le développement par 5 – fluorouracil

Xie, Bingning 03 November 2016 (has links)
Les ARNm codent pour les protéines, tandis qu'un grand nombre d'ARNs nommés longues ARNs non codants (ARNlnc) ne sont pas traduites en protéines. Les deux types d’ARNs existent en isoforms qui se distinguent à cause de l’épissage alternatif. Certains des ARNlnc jouent des rôles importants dans la croissance et différentiation cellulaire. Cependant, leurs fonctions dans la cytotoxicité de la chimiothérapie anti-cancéreuse médicamenteuse utilisant le 5-fluorouracile (5-FU) sont encore inconnues. Pendant mes travaux j'ai trouvé que le traitement par le 5-FU cause l’accumulation des ARNlnc. Ce phénomène est parfois, sous forme d’ARN double brin (ARNds) formé par une paire de transcrits chevauchant, corrélé négativement avec le niveau de la protéine codée par l'ARNm. Cette inhibition potentielle de la traduction des régulateurs du cycle cellulaire clés et les gènes essentiels en formant des l'ARNds peut éventuellement empêcher la progression du cycle cellulaire. Nos analyses prometteuses devraient inspirer des études approfondies des ARNlnc dans la cytotoxicité du 5-FU chez la levure et l’homme afin d’'améliorer la chimiothérapie. J'ai trouvé que la surexpression de RRP6, peut conduire à une résistance accrue au traitement par le 5-FU. Je démontre ensuite que l’ARNlnc MUT1312 forme des ARNds avec RRP6 qui sont négativement corrélés avec le niveau de la protéine Rrp6. Par ailleurs, la surexpression de MUT1312 pendant la mitose et associé avec une diminution d’Rrp6. Ainsi, mon étude suggère que MUT1312 soit impliqué dans la régulation de Rrp6 pendant la differentiation cellulaire. Mes recherches de MUT477/SWI4 indiquent la function importante de la méiose induite à long ARN non codantes en tant que forme d'ARN double brin potentiellement réguler la traduction. J'ai trouvé que SUT200 pourrait inhiber la transcription de CDC6 durant la méiose par read-through. Un cas comparable est MUT1465 et CLN2. J’ai fait un criblage in silico pour trouver des facteurs de transcription qui activent des MUTs durant la méiose. J’ai trouvé que la plupart des MUTs sont induites par Ndt80. MUT1465 est parmi eux : il pourrait être induite par Ndt80 ce qui inhiberait l’expression de CLN2 après l’initiation de la méiose. J’ai trouvé que la répression de certains MUTs par le complexe Ume6/Rpd3 en mitose est différemment régulée entre JHY222 et SK1. MUT100 qui ne possède pas l'élément USR1 fixé par Ume6, et qui est donc une cible indirecte, est déréprimé dans JHY22 ume6 mais pas dans SK1 ume6. Pour la régulation de l'étude de isoforme méiose, Nous avons trouvé que le complexe histone déacétylase Rpd3/Sin3/Ume6, empêche également l'induction de l'isoforme longue de BOI1 dans la mitose par liaison directe de liaison Ume6 à sa cible de URS1. Orc1 est importante pour la réplication de l'ADN. J’ai démontré que mORC1 est une cible directe de l'activateur Ndt80 et que son motif de fixation (MSE) est nécessaire pour l'induction de l’isoforme mORC1 et du gene méiotique SMA2 transcrit de façon divergente. J’ai trouvé qu'une souche incapable d’induire mORC1, contient des niveaux anormalement élevés d’Orc1 pendant la gamétogenèse, ce qui corréle mORC1 avec la baisse de la protéine Orc1. En conclusion, mes études au cours du doctorat révèlent des nouvelles cibles et ainsi offrent des nouvelles perspectives de l’amélioration de la chimiothérapie par le 5-FU. Les mécanismes incluent la formation d'un ARN double brin avec son ARNm anti-sens pour potentiellement inhiber la traduction de l'ARNm, et inhibition en aval de l'ARNm par transcription read-through d’une ARNlnc. Mon travail a également révélé un mécanisme de régulation des ARNlnc et les isoforms d’ARN pendent la croissance et la différentiation cellulaire. / RNAs are molecules with important functions in diverse cellular processes. mRNAs encode proteins, while a large number of RNAs called long noncoding RNAs (lncRNAs) are not translated into proteins. Both types of RNAs exist in various isoforms due to alternative splicing.Some of lncRNA play important roles in cell growth and differentiation. However, their functions in the cytotoxicity of the drug anticancer chemotherapy using 5-fluorouracil (5-FU) are still unknown. During my research I found that treatment with 5-FU causes accumulation of lncRNA. Acuumulated antisense lncRNA form double stranded RNA with the mRNAs , negatively correlated with the level of the protein encoded by the mRNA. This potential inhibition of translation of key cell cycle regulators and essential genes by forming dsRNA may possibly prevent the progression of the cell cycle. My results suggest that lncRNA are likely to play an important role in the cytotoxicity of 5-FU. Our promising testing should inspire in-depth studies of lncRNA in the cytotoxicity of 5-FU in yeast and humans to improve chemotherapy.Rrp6 is a 3'-5 'exoribonuclease, which plays an important role in the regulation and modification of rRNA, mRNA and lncRNA. I found that overexpression of RRP6, the homologue of the yeast EXOSC10 gene in mammals, can lead to increased resistance to treatment with 5-FU. I found that the lncRNA MUT1312 form dsRNA with RRP6 that are negatively correlated with the level of Rrp6 protein. Furthermore, overexpression of MUT1312 during mitosis and associated with a decrease of Rrp6. Thus, my study suggests that MUT1312 may involved in the regulation of Rrp6 during cell differentiation. I further explored the function of the double-stranded RNA in meiosis. My research about SWI4/MUT477 indicates the important function of meiosis induced long noncoding RNA as a form of double-stranded RNA potentially regulate translation. Another aspect of the function of lncRNA is to regulate the transcription of downstream mRNA. I found SUT200 could inhibit transcription of CDC6 during meiosis by read-through. A similar case is CLN2/MUT1465. I did an in silico screening to find transcription factors that activate MUTs during meiosis. I found that most MUTs are induced by Ndt80. MUT1465 is among them: it could be induced by Ndt80 which inhibit the expression of CLN2 after initiation of meiosis. I found that repression of certain MUTs by the Ume6 / Rpd3 complex in mitosis is regulated differently between JHY222 and SK1. MUT100 which does not have the Ume6 binding site URS1 element, and is therefore an indirect target is derepressed in JHY22 ume6 but not in SK1 ume6. For the study about regulation of meiosis isoform, we have found that the histone deacetylase complex Rpd3 / Sin3 / Ume6 prevents the induction of long isoform BOI1 in mitosis by direct binding Ume6 binding to its target URS1.Orc1 is important for DNA replication. I have demonstrated that mORC1 is a direct target of the Ndt80 activator and its binding motif (MSE) is required for induction of isoform mORC1 and meiotic gene SMA2 divergently transcribed. I found that a strain incapable of inducing mORC1 contains abnormally high levels of Orc1 during gametogenesis, which correlates with mORC1 declining Orc1 protein. Since eukaryotic genes often encode multiple transcripts with 5'-UTR of variable length, the findings are likely relevant to gene expression during development and disease in higher eukaryotes. In conclusion, my studies during PhD reveal new targets and thus offer new prospects for improving chemotherapy with 5-FU. Mechanisms include (1) the formation of a double strand with its antisense mRNAs to potentially inhibit translation of mRNA, and (2) downstream inhibition of mRNA transcription read-through of a lncRNA. My work also revealed a lncRNA regulatory mechanism and RNA isoforms dangling growth and cell differentiation.
4

Pharmacogenetics and colorectal cancer / Pharmacogénétique et cancer colorectal

Benhaim, Léonor 19 November 2013 (has links)
Le champ de la pharmacogénétique est d'une importance cruciale en oncologie pour optimiser la sélection du traitement à utiliser en fonction du profil génomique du patient et de la tumeur. En effet, au-delà des caractéristiques spécifiques de la tumeur, le génome de l'individu explique une grande partie de la variation de la réponse du observée à des agents chimiothérapeutiques à la fois en terme d'efficacité et de toxicité. Les patients atteints de cancer colorectal (CCR) sont susceptibles de recevoir une ou plusieurs lignes de chimiothérapie avec une efficacité variable et de faire l'expérience des effets secondaires connexes. Il est donc essentiel d'optimiser l’arsenal thérapeutique pour améliorer l’efficacité des traitements en évitant au maximum les effets indésirables. Le but des études de pharmacogénétique est d'étudier spécifiquement pour chaque médicament les voies métaboliques impliquées et leurs variations interindividuelles potentielles secondaires à des mutations génomiques ou somatiques. Cette recherche vise ainsi à identifier les biomarqueurs pronostiques et prédictifs qui aideront à une meilleure sélection de traitement. Pour les patients atteints de CRC, le bénéfice de survie de l'administration de la chimiothérapie adjuvante chez les patients de stade II et III reste à évaluer. En effet, l'avantage de survie donné par la perfusion de 5-fluorouracile en adjuvant (avec ou sans oxaliplatine) a été montré pour les patients de stade III CRC mais est encore indéterminé pour les patients de stade II CRC. Par définition, les mutations somatiques sont détectées dans le génome des cellules tumorales et ont été associées à la réponse aux agents chimiothérapeutiques. En outre, plusieurs rapports ont suggéré l'importance du rôle des variations héréditaires (génome constitutionnel) pour la réponse aux médicaments et à la prévision des effets secondaires. Dans ce travail, je me suis concentrée sur la relation entre les polymorphismes et la réponse aux chimiothérapies chez les patients de stade II - III CRC. J'ai observé que la cycline D1 (CCND1), les canaux sodique voltage-dépendants (SCN1A), les régulateurs de la voie WNT / β - caténine, KSR et les gènes de cellules souches cancéreuses pouvaient prédire la réponse et la survie de patients traités pour CCR en situation adjuvante. / The pharmacogenetics field is of crucial importance in oncology to optimize the selection of which chemotherapy regimen to use according to the patient’s and tumor’s genomic profile. Indeed, beyond the specific tumor characteristics, the individual’s inherited genome accounts for a large proportion of the variation in patient’s response to chemotherapeutic agents both in term of efficiency and toxicity. Patients with colorectal cancer are likely to receive one or several lines of chemotherapy with variable efficacy and to experience some related side effects. It is therefore critical to tailor the best therapeutic arsenal to improve treatments efficacy meanwhile avoiding adverse reactions susceptible to lead to treatment disruption as much as possible. The purpose of pharmacogenetics studies is to specifically investigate for each drug the implicated metabolic pathways and their potential individual variations related to genomic or somatic mutations. This research aims at identifying both prognostic and predictive biomarkers that will help for the best treatment selection. In CRC, one important issue remains to evaluate the survival benefit of adjuvant chemotherapy administration in patients with stage II and III CRC. In this setting, the survival advantage given by adjuvant 5-fluoruracil-infusion (with or without oxaliplatin) has been shown for patients with stage III CRC but is still undetermined for patients with stage II CRC. By definition somatic mutations can be found in tumor cells genome and have been related with response to chemotherapeutic agents. In addition, several reports suggested the important role of inherited variations (constitutional or germ line) for drug response and side effects prediction.
5

Fabrication and characterization of 5-Fu loaded poly(lactide-Co-Glycolide) millirods: assessment of their suitability for local tumor treatment

Leelakanok, Nattawut 01 August 2017 (has links)
The synthetic chemotherapeutic agent, 5-FU, has been used for the treatment of a variety cancers, with colorectal cancer being among the most susceptible. Administration of 5-FU by continuous intravenous infusion has proven to yield greater antitumor efficacy and lower hematotoxicity compared to administration of 5-FU by intravenous bolus injections. Nevertheless, systemic application of 5-FU is often limited by its narrow therapeutic threshold, and therefore in certain situations, such as tumor resection, it may be more appropriate to provide local rather than systemic delivery of 5-FU. It was therefore proposed that 5-FU loaded PLGA millirods may be capable of providing sustained release of 5-FU at a local level which may have equivalent or greater antitumor activity and less cytotoxicity than the systemic or local delivery of soluble 5-FU. PLGA millirods loaded with 5-FU were successfully fabricated by a hot-melt extrusion technique and characterized for in vitro and in vivo release rates. It was demonstrated that percentage loading by weight of 5-FU could be adjusted to modify its release kinetics. It was also shown that millirods could be stably stored under a variety of conditions for at least 2 months. An optimal millirod formulation (PLGA 50:50 loaded with 5-FU (50% w/w)) was tested for antitumor activity and general toxicity in vivo. At the dose of 120 mg/kg 5-FU, millirods (delivered peritumorally) were efficacious (with 100% survival rates) against solid thymomas in tumor-challenged mice (causing complete regression). Whilst the soluble form of 5-FU (delivered intraperitoneally (IP) at 120 mg/kg) was also highly efficacious (90% survival rates) against thymomas it was also more hematotoxic. In addition, the millirod form provided significantly greater antitumor activity against colorectal tumors in mice compared to the soluble form of 5-FU. In terms of in vivo toxicity, surprisingly, the type of formulation did not have a significant effect on mouse weight despite both IP and subcutaneous (SC) delivery causing death of some mice. Importantly, it was found that 5-FU loaded PLGA millirods were significantly less hematotoxic than soluble 5-FU delivered by either IP or SC injection at the equivalent dose. Thus, locally implanted 5-FU loaded PLGA millirods appeared to be less toxic and possessed overall greater antitumor potency than soluble 5-FU delivered by IP or SC injection. This study further investigated whether the combination of 5-FU loaded PLGA millirods with eniluracil (in both thymoma and colorectal tumor models) or immune checkpoint inhibitors (in the colorectal tumor model) could enhance the antitumor efficacy of 5-FU millirods in mice challenged with colorectal tumors. It was found that the combination of 5-FU loaded PLGA millirods and eniluracil (millirod or solution forms) did not significantly enhance the antitumor efficacy of 5-FU millirods in either tumor models. It was also found that immune checkpoint inhibitors did not enhance the antitumor efficacy of 5-FU loaded PLGA millirods in the colorectal tumor model.
6

Intensification thérapeutique dans les cancers colorectaux par des études pharmacogénétiques et pharmacogénomiques

Capitain, Olivier 09 March 2010 (has links) (PDF)
Le cancer colorectal représente un défi thérapeutique compte tenu de sa fréquence (38 000 nouveaux cas annuels dans notre pays), et de sa gravité (moins de 10 % de survie à 5 ans en situation métastatique). Sa prise en charge adéquate est avant tout multidisciplinaire associant les nouvelles techniques de chirurgie et de radiologie à la chimiothérapie. Celle-ci est représentée par trois cytotoxiques majeurs : le 5-Fluorouracile, pierre angulaire du traitement, l'oxaliplatine (L-OHP) et enfin l'irinotecan (CPT-11), auxquels se sont ajoutées ces dernières années les biothérapies ciblant le facteur angiogénique VEGF (bevacizumab) ou le récepteur épithélial de surface EGFR (cetuximab, panitumumab). Notre travail de Thèse d'Université a cherché à explorer, chez des patients atteints d'un cancer colorectal métastatique, le retentissement sur les taux de réponses, les survies et les toxicités, de génotypes enzymatiques impliqués dans les métabolismes des trois cytotoxiques principalement utilisés dans cette indication. Nos études translationnelles montrent l'optimisation des traitements à base de 5-FU par l'approche pharmacocinétique associée au dépistage préthérapeutique d'une population à haut risque de toxicité (DPYD mutés et/ou rapport UH2/U abaissé). Par ailleurs apparaissent de mauvais pronostic sur la survie globale et en cas de monochimiothérapie par 5-FU, les patients 3R/3R pour TYMS et homozygote sauvage pour MTHFR 1298 A>C ou 677 C>T, facteurs de risques génotypiques disparaissant avec l'adjonction de CPT-11. Concernant ce dernier, un schéma de traitement adapté au statut UGT 1A1, et combiné au cetuximab, aboutit à des taux de maladie contrôlée et de survie sans progression inégalés en deuxième ligne de traitement. Enfin, les patients homozygotes T/T pour ERCC1 118 C>T et C/C XPD 751 A>C apparaissent à risque de neurotoxicité chroniques à l'oxaliplatine. Considérant le génome tumoral, outre Kras et Braf, PI3KCA muté apparaît pour la première fois comme un facteur possible de résistance aux traitements anti-EGFR. En conclusion, la prise en compte des facteurs pharmacogénétiques et pharmacogénomiques devrait permettre à l'avenir une meilleure rationalisation des traitements de chimiothérapies en optimisant leurs efficacités tout en limitant leurs toxicités.
7

Proteomic analysis of differentially expressed proteins in colorectal cancer

Lee, Mau-You 16 August 2005 (has links)
We gathered normal and colorectal cancer tissues from 18 patients after tumor surgery. The tumor tissues represent caner stages from T1 to T4 (TNM system).Two-dimensional electrophoresis and MALDI-TOF techniques were utilized to identify the differentially expressed proteins. Our studies showed that there are about 18 differentially expressed proteins in normal and tumor tissues (p<0.05) which 13 proteins increased in tumor were Keratin 8, Protein disuflde isomerase A3 precursor, Keratin 18, Fractalkine precursor, LDH-B, Tropomyosin alpha 4 chain, Tropomyosin alpha 3 chain, chloride intracellular channel protein 1, PTTG1(Pituitary tumor-transforming protein 1),
8

Role of 5-FU in DNA double strand break repair for improved targets in colorectal cancer therapy

Sai Srinivas, Upadhyayula 07 November 2014 (has links)
No description available.
9

Targeted use of umbilical cord matrix stem cells for cancer therapy

Rachakatla, Rajashekar January 1900 (has links)
Doctor of Philosophy / Department of Anatomy and Physiology / Deryl L. Troyer / Umbilical cord matrix stem (UCMS) cells are derived from Wharton's jelly and have been shown to express genes characteristic of primitive stem cells. They can be isolated in large numbers in a short time and thus potentially represent an abundant source of cells for therapeutic use. We investigated the migratory nature of human UCMS cells towards MDA 231 human breast carcinoma cells in an in vitro model of cell migration; UCMS cells cultured with or without MDA 231 cells for 24 hours. Next, we evaluated the effect of chemokines, stromal derived factor 1 (SDF-1) and vascular endothelial growth factor (VEGF) on human UCMS cells by treating with increasing doses of SDF-1 and VEGF. UCMS cells were found to migrate towards MDA 231 cells in a dose dependent manner. Both SDF-1 and VEGF induced migration of UCMS cells in a dose dependent manner. These results suggest that MDA 231 cells might be releasing chemokine factors, such as SDF-1 and VEGF, which promote UCMS cell migration towards the tumor cells in vitro. Stem cells that migrate to tumors may allow targeted delivery of therapeutic agents that otherwise may have severe side effects. To evaluate the selective engraftment and therapeutic efficiency of human UCMS cells that were engineered to express interferon beta (UCMS-IFN-beta) MDA 231 cells (2,000,000) were intravenously injected into severe combined immune deficient (SCID) mice, followed by three weekly intravenous injections of fluorescently labeled UCMS-IFN-beta cells (500,000). To evaluate the synergistic effect of 5-Fluorouracil (5-FU) and IFN-beta, MDA 231 cells were intravenously injected into SCID mice, followed by three weekly intravenous injections of fluorescently labeled UCMS-IFN-beta cells and three weekly intra peritoneal injections of 5-FU. In both of the above experiments, mice were euthanized one week after the last UCMS cell transplant and lung weights were compared to the controls to determine the differences in tumor burden. After transplantation of UCMS-IFN-beta cells into MDA 231 tumor-bearing mice, UCMS cells were found near or within metastatic lung tumors but not in other tissues, and in these animals, the lung weight was significantly less than MDA 231 tumor-bearing animals that received saline injections. Histologically, there was significant reduction in the tumor area in MDA 231 tumor bearing lungs after UCMS-IFN-beta treatment. When 5-FU was given along with UCMS-IFN-beta cells, there was further reduction in tumor area. These results indicate that UCMS cells can potentially be used for targeted delivery of cancer therapeutics.
10

Metal-organic Frameworks as Drug Delivery System for Cancer Therapy

Lima de Meneses Precker, Rafaella 31 August 2022 (has links)
Die Forschung an porösen Hybridmaterialien hat sich rasch entwickelt, und in letzter Zeit ist die Anzahl neuer Strukturen und Zusammensetzungen aufgrund ihrer vielfältigen Anwendungsmöglichkeiten im Bereich des Kristall-Engineering von großem Interesse. Metall-organische Gerüste (metal-organic frameworks, MOFs) sind eine aufstrebende Klasse von Nanomaterialien, deren Eigenschaften durch Variation der Bausteine, die aus Metallionen und organischen Liganden bestehen und sich koordinativ zu einer dreidimensionale Struktur verbinden lassen, leicht angepasst werden können. Eigenschaften wie eine große Oberfläche und eine hohe Porosität verleihen diesen Materialien vielversprechende Eigenschaften, um als Wirtsmaterial verwendet zu werden. Die vorliegende Arbeit konzentriert sich auf die Synthese der Verbindung [Fe3O(H2O)2(OH)(bdc)3]n (bcd = 1,4-Benzoldicarboxylat; MIL-101(Fe), MIL = Materials of Institut Lavoisier), die aus einem carboxylato-verbrückten, oxido-zentriertem, dreikernigen Fe3+-Komplex besteht. Die Struktur besitzt große Poren (Ø: 29 und 34 Å) und eine große Oberfläche mit der Fähigkeit, zahlreiche Moleküle einzuschließen. In der vorliegenden Arbeit wird MIL-101(Fe) als Arzneimittelabgabesystem verwendet. Curcumin, Capecitabin und 5-Fluorouracil (5-FU) wurden als Modellarzneimittel für die Verkapselung in der MIL-101(Fe)-Struktur ausgewählt. Es wurden verschiedene Freisetzungsregime in unterschiedlichen biologischen Medien untersucht. Nach vielversprechenden ersten Ergebnissen bei der Freisetzung dieser Medikamente aus der MIL-101(Fe)-Struktur wurde anschließend die selektive Lasersintertechnik (SLS) verwendet. Die SLS ist ein additives Schichtbauverfahren, das sich in dieser Arbeit als ressourcenschonende Technologie für die schnelle Herstellung erwiesen hat. Die Möglichkeit, die Größe, Form und Geometrie der hergestellten Proben individuell anzupassen, bot die Gelegenheit, die Wirkstofffreisetzung zu modulieren und den Freisetzungszeitraum zu verlängern. / The field of porous hybrid materials has grown rapidly; recently the number of new structures and compositions are of great interest in the crystal-engineering field, due to their various possible applications. Metal-organic frameworks (MOFs) are an emerging class of nanomaterials, whose properties can be easily adjusted by varying the molecular building blocks, obtained from metal ions and organic ligands that can be combined to three-dimensional structures. Properties such as high surface area and high porosity give these materials promising characteristics to be used as host materials. The present work focuses on the synthesis of [Fe3O(H2O)2(OH)(bdc)3]n (bcd = 1,4-benzenedicarboxylate; MIL-101(Fe), MIL = Materials of Institut Lavoisier), composed of carboxylate-bridged, oxido-centered, trinuclear Fe3+ complexes. The iron-based structure features large pore sizes (Ø: 29 and 34 Å) and high surface area with the ability to encapsulate numerous molecules, for use as a drug delivery system in the present work. The curcumin, capecitabine, and 5-fluorouracil (5-FU) were chosen as model drugs for the encapsulation into the MIL-101(Fe) structure. Different delivery regimes were studied in different biological media. After promising initial results with the release of these drugs from the MIL-101(Fe) structure, the selective laser sintering technique (SLS) was introduced subsequently. The SLS is an additive layer manufacturing technique that has emerged in this work as a resourceful technology for rapid manufacturing, the possibility to customize the size, shape, and geometry of the manufactured samples, thus providing the opportunity to modulate the drug release extending it for even longer periods of time.

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