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The peritoneal tumor is not named after the originating of cancer cells but instead contains all tumors appearing in the region of the peritoneal cavity. There are over 250,000 new cases of malignant diseases originating from organs in the peritoneal cavity annually in the USA, and most of these cases spread by intraperitoneal seeding. Cytoreductive surgery for removal and debulking of metastases in the peritoneal cavity is the primary treatment option. Complete surgical removal of the cancerous tissues, however, is difficult to achieve because positive margins are often left behind, and it is difficult to detect the small metastases in the peritoneal cavity. Methyl aminolevulinate (MAL), a protoporphyrin X (PplX) prodrug, has been clinically used for photodynamic therapy of local malignancies such as Basal Cell Carcinoma and Actinic Keratosis. Its application for cancers in the peritoneal cavity, however, has been limited by its non-specific biodistribution and adverse effects. Since nanoparticles can play an essential role as drug deliver platforms as a result of their loading capacity, sustained drug release profile, and potential targeting ability, I proposed a liposomal delivery system, Folic-modified liposome (FL). The goal of this study is to take advantage of this observation by developing a FL system of MAL for photodynamic diagnosis and therapy of cancers in the peritoneal cavity in a more specific and efficient manner. Based on the results presented, FL has the potential to improve cytoreductive surgery in the following manner: a) A hydrophilic core can encapsulate high amounts of MAL and protect it from metabolic degradation; b) FL systems loaded with MAL can enlarge the gap between PpIX accumulation in tumor cells and normal tissues. c) FL system loaded with MAL can provide photodynamic diagnosis and photodynamic therapy as complementary functions. / Pharmaceutical Sciences

京都大学 / 新制・課程博士 / 博士(薬科学) / 甲第24549号 / 薬科博第166号 / 新制||薬科||18(附属図書館) / 京都大学大学院薬学研究科薬科学専攻 / (主査)教授 髙倉 喜信, 教授 山下 富義, 教授 小野 正博 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM

京都大学 / 新制・課程博士 / 博士(薬学) / 甲第24563号 / 薬博第861号 / 新制||薬||243(附属図書館) / 京都大学大学院薬学研究科薬学専攻 / (主査)教授 髙倉 喜信, 教授 山下 富義, 教授 小野 正博 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM

Η σισπλατίνη αποτελεί ένας ευρέως διαδεδομένο αντικαρκινικό φάρμακο. Ωστόσο προκαλεί σοβαρές παρενέργειες εξαιτίας της έλλειψης εκλεκτικότητας που παρουσιάζει. Για αυτόν το λόγο, γίνεται προσπάθεια ενκαψακίωσης της σισπλατίνης σε νανοφορείς ώστε να επιτευχθεί η εκλεκτική μεταφορά της στον καρκινικό ιστό με μηχανισμούς παθητικής ή ενεργητικής στόχευσης. Στην παρούσα εργασία, παρασκευάστηκαν μαγνητικοί νανοφορείς σισπλατίνας και ελέγχθησαν οι ιδιότητες φόρτωσης με σισπλατίνη και αποδέσμευσης, η κολλοειδής σταθερότητα και η in vitro αντικαρκινική δραστικότητα. Τα νανοσωματίδια (οι μαγνητικοί νανοφορείς) συντέθηκαν με τη σύνδεση του συμπολυμερούς πολυμεθακρυλικό οξύ – πολυαιθυλενογλυκόλη (poly(methacrylic acid)-graft-poly(ethyleneglycol methacrylate)) σε μαγνητικούς νανοκρυσταλλίτες. Ενώ το πολυμεθακρυλικό οξύ παρέχει τις απαραίτητες καρβοξυλομάδες στο σύστημα για τη σύνδεση της σισπλατίνης, οι αλυσίδες πολυαιθυλενογλυκόλης προσφέρουν στερεοχημική σταθεροποίηση στα νανοσωματίδια. Αρχικά παρασκευάστηκαν μαγνητικοί νανοφορείς με διαφορετικούς τύπους p(MAA-g-EGMA) συμπολυμερών τα οποία διέφεραν ως προς το μήκος και την πυκνότητα των αλυσίδων PEG. Τα μαγνητικά νανοσωματίδια παρασκευάστηκαν με τη μέθοδο της υδρολυτικής, αλκαλικής καταβύθισης από μία πρόδρομη ένωση δισθενούς σιδήρου παρουσία των παραπάνω συμπολυμερών. Οι νανοφορείς σε επόμενο στάδιο φορτώθηκαν με τη σισπλατίνη μετά από επώαση τους με το φάρμακο. Επιπλέον διερευνήθηκε η επίδραση του pH στην φόρτωση της σισπλατίνης. Οι νανοφορείς χαρακτηρίστηκαν ως προς την υδροδυναμική τους διάμετρο και το επιφανειακό τους φορτίο μέσω της τεχνικής της δυναμικής σκέδασης φωτός (DLS) και μικροηλεκτροφόρησης αντίστοιχα. Πραγματοποιήθηκαν μελέτες αποδέσμευσης του φαρμάκου από τους νανοφορείς σε διάλυμα φωσφορικών (pH=7.4) στους 37°C. Επιπροσθέτως, διερευνήθηκε η επίδραση της εφαρμογής εξωτερικού εναλλασσόμενου μαγνητικού πεδίου (400 kHz) στην αποδέσμευση της σισπλατίνης από τους νανοφορείς μέσω της πρόκλησης υπερθερμίας. Τέλος, εκτιμήθηκε η κυτταροτοξικότητα των φορτωμένων με σισπλατίνη νανοφορέων και συγκρίθηκε με την κυτταροτοξικότητα των κενών νανοσωματίδιων και του φαρμάκου. Ο έλεγχος κυτταροτοξικότητας πραγματοποιήθηκε μέσω της τεχνικής της κυτταρομετρίας ροής, μετά από χρώση των κυττάρων (Α549, καρκινικά κύτταρα πνεύμονα) με τη χρωστική του ιωδιούχου προπιδίου (PI). Οι p(MAA-g-EGMA) μαγνητικοί φορείς σισπλατίνης που παρασκευάστηκαν στην παρούσα εργασία παρουσίασαν μεγάλη σταθερότητα στο χρόνο ως προς την υδροδυναμική τους διάμετρο και το επιφανειακό τους φορτίο. Επιπλέον παρουσίασαν ικανοποιητική φόρτωση φαρμάκου (6-8%). Η αύξηση του pH (μέχρι 10), η αύξηση των ανιονικών θέσεων (καρβοξυλομάδες) και η μείωση του PEG βρέθηκε να οδηγούν σε αύξηση της φόρτωσης της σισπλατίνης στους νανοφορείς. Παρατηρήθηκε παρατεταμένη αποδέσμευση του φαρμάκου (σισπλατίνης) από τους νανοφορείς, με τον ρυθμό αποδέσμευσης να επηρεάζεται από την πολυμερική σύνθεση των νανοφορέων. Τέλος, οι νανοφορείς παρουσίασαν χαμηλή κυτταροτοξικότητα ενώ οι νανοφορείς φορτωμένοι με σισπλατίνη παρουσίασαν τοξικότητα συγκρίσιμη με αυτήν του φαρμάκου. Με βάση τα ληφθέντα αποτελέσματα, οι p(MAA-g-EGMA) μαγνητικοί νανοφορείς σισπλατίνης έχουν ικανοποιητικές ιδιότητες κολλοειδούς σταθερότητας, φόρτωσης σε φάρμακο και αποδέσμευσης, γεγονός που δικαιολογεί την περαιτέρω διερεύνηση της πιθανής χρησιμοποίησης τους ως φορείς στοχευμένης χορήγησης σισπλατίνας. / Cisplatin is a potent anticacer agent. However, it exhibits serious side effects due to lack of selectivity. Therefore, a more selective cisplatin delivery to tumors is pursued by incorporating cisplatin in targetable nanocarriers. In this work, hybrid magnetic nano-asssemblies loaded with ciplatin were prepared and evaluated in vitro. The nano-assemblies were synthesized through grafting of poly(methacrylic acid)-graft-poly(ethyleneglycol methacrylate) (p(MAA-g-EGMA) on magnetite nanocrystallites. Poly(ethylene glycol) chains confer to the nanocarriers bio-repellent properties. The formation of a distinct second inner polymeric corona with an abundance of carboxylate groups provides the binding sites for cisplatin molecules. Different types of p(MAA-g-EGMA) copolymers with varying length and density of PEG chains were synthesized. Core-shell magnetic nano-assemblies were prepared by hydrolytic alkaline precipitation from a single ferrous molecular precursor in the presence of the above p(MAA-g-EGMA) copolymers . The nano-assemblies were loaded with cisplatin by incubating them with cisplatin solutions of different cisplatin concentration. The nano-assemblies were characterized with regard to their size and zeta potential at different salt concentrations using dynamic light scattering (DLS). The effect of pH on cisplatin loading was investigated. Drug release studies were performed spectrophotometrically in phosphate buffered saline (pH 7.4) at 37°C. The influence of applying an AC magnetic field on the release profile of cisplatin was also investigated using a home-made AC (400 kHz) magnetic field generator 5 mT. The cytotoxicity of blank and cisplatin-loaded nano-assemblies against A549 human lung cancer cell line was assessed by flow cytometric measurement of cellular fluorescence after staining with propidium iodide (PI). The nanocarriers had suitable size properties for intravenous administration and accumulation to tumors based on the enhanced permeability and retention phenomenon (EPR effect). They also were found to exhibit very good colloidal stability, satisfactory cisplatin loading efficiency (around 6% w/w at optimum experimental conditions) and sustained drug release properties, with the rate of release to be significantly increased in response to external AC magnetic fields. Furthermore, the blank nanocarriers did not exhibit cytotoxicity whereas the cisplatin-loaded nanocarriers exhibited comparable to the free ciplatin cytotoxicity against A549 cancer cells. The obtained results justify further evaluation of p(MAA-g-EGMA) nanocarriers as targeted drug delivery system of cisplatin.

L'objectif de cette thèse consiste à développer une approche globale couplant les procédés sol-gel, les propriétés d'auto-assemblage des tensioactifs et l'atomisation séchage afin d'encapsuler directement des principes actifs dans des microsphères nanostructurées. Nous nous attachons en particulier à étudier les variations de la localisation et l'état physique des principes actifs en fonction des paramètres de synthèse. Le but de ce travail est également de mettre en relation les propriétés de libération avec la texture et la composition des microsphères. En parallèle, cette thèse a aussi pour objectifs la découverte de nouvelles familles de matériaux texturés et l'approfondissement des connaissances sur les mécanismes de formation des microsphères mésoporeuses. / For the first time, a new one-pot synthesis approach associating sol-gel, self-assembly andspray-drying allows in forming microspheres with tuneable textures (worm-like mesophases,drug nano-domains, core-shell organisation) and drug delivery properties (from burst todelayed releases). The parameters which control these properties are the surfactant content,the nature of the couples (drug, surfactant) as well as the functionalisation of the siloxanenetwork.

O objetivo deste estudo foi avaliar clinicamente em humanos sistemas semissólidos (géis) e filmes contendo sal de metronidazol e conjugado de benzoato de metronidazol associados à raspagem e alisamento radicular (RAR), para o tratamento de periodontite. Foram avaliados o pH do fluido crevicular, os níveis clínicos de inserção óssea de suporte aos dentes envolvidos no tratamento periodontal, antes e após os tratamentos, além do perfil de liberação dos fármacos por meio de cromatografia líquida de alta eficiência (CLAE). Participaram do estudo 45 pacientes da Faculdade de Odontologia de Ribeirão Preto USP, de ambos os gêneros, os quais possuíam ao menos 2 dentes com periodontite crônica, compondo um total para o estudo de 96 dentes, divididos aleatoriamente em 3 grupos: grupo 1 raspagem e alisamento radicular (RAR) controle ativo; grupo 2 RAR + filme com metronidazol; grupo 3 RAR + gel de metronidazol. As concentrações de metronidazol e o tempo de liberação do fármaco no fluido crevicular gengival foram monitorados, avaliando-se ainda os efeitos dessas formulações com relação a parâmetros clínicos da periodontite. Os efeitos dos tratamentos foram avaliados pelo acompanhamento longitudinal de parâmetros clínicos (profundidade de sondagem, nível clínico de inserção e sangramento à sondagem). Os resultados da análise das concentrações de metronidazol e benzoato de metronidazol na bolsa periodontal dos pacientes foram considerados em avaliação paralela intragrupos e demonstraram que o filme e o gel foram detectados em concentração efetiva até 48 horas após a aplicação in situ, porém não foi observada diferença significante entre os grupos avaliados. Quanto aos valores de pH após o tratamento, eles variaram entre 6 e 8. No nível clínico de inserção houve diferença estatística significante entre os três grupos avaliados, sendo que o grupo que recebeu apenas tratamento periodontal convencional apresentou os melhores valores. Houve redução progressiva do sangramento à sondagem nos tempos T15 e T30 nos três grupos considerados. No que se refere aos parâmetros clínicos, ambas as terapias (gel e filme) foram eficazes em promover a redução na profundidade à sondagem, ganho no nível clínico de inserção e apresentaram melhora na saúde periodontal considerando-se o menor sangramento após a sondagem que o grupo controle (RAR somente). / The objective of this study was to clinically evaluate in humans semisolid (gels) and films systems containing metronidazole and metronidazole benzoate conjugate salts associated with scaling and root planing (SRP) for the treatment of chronic periodontitis. It was evaluated the pH of crevicular fluid and clinical bone attachment levels of the teeth involved in periodontal disease, before and after treatment, in addition to the release profile of drugs by high-performance liquid chromatography (HPLC). The study included 45 patients (both genders), from School of Dentistry of Ribeirão Preto, University of São Paulo, which had at least two teeth with chronic periodontitis, making a total for the study of 96 teeth which were randomly divided into 3 groups: Group 1 - scaling and root planing (SRP) - active control; Group 2 - RAR + film with metronidazole; Group 3 - SRP + gel with metronidazole. The metronidazole concentration and the drug release profile time in gingival crevicular fluid were monitored by evaluating the effects of such formulations, further with respect to clinical parameters of periodontitis. The effects of the treatments were evaluated for longitudinal monitoring of clinical parameters (probing depth, clinical attachment level and bleeding on probing). The results of the analysis of metronidazole and metronidazole benzoate concentrations in periodontal pockets of the patients were considered in a intragroup parallel evaluation and showed that the film and the gel were both detected in effective concentration till 48 hours after in situ application, but there was no difference significant between the groups. As for pH values after treatment, they ranged from 6 to 8. In clinical attachment level it was no statistically significant difference among the three groups, and the group that received only conventional periodontal treatment showed the best values. There was a progressive reduction in bleeding on probing in T15 and T30 times in all the three groups considered. With regard to clinical parameters, both therapies have been effective in promoting reduction in probing depth and gain in clinical attachment level as the control group, and both therapies showed improvement in periodontal health considering minor bleeding after probing that the (SRP alone) control group.

The goal of this thesis was to develop a new drug-delivering material to deliver anti-inflammatory protein for treating OA. Our central hypothesis for this work is that a controlled release/presentation system will more effectively deliver anti-inflammatory protein therapies to the OA joint. The primary goal of this work was to synthesize a block copolymer that could self-assemble into injectable, sub-micron-scale particles and would allow an anti-inflammatory protein, IL-1ra, to be tethered to its surface for efficient protein delivery. The block copolymer incorporated an oligo-ethylene monomer for tissue compatibility and non-fouling behavior, a 4-nitrophenol group for efficient protein tethering, and cyclohexyl methacrylate, a hydrophobic monomer, for particle stability. We engineered the copolymer and tested it in both in vitro culture experiments and an in vivo model to evaluate protein retention in the knee joint. The rationale for this project was that the rational design and synthesis of a new drug- and protein-delivering material can create a modular polymer particle that can deliver multi-faceted therapies to treat OA. This work characterizes the in vitro and in vivo behavior of our polymer particle system. The protein tethering strategy allows IL-1ra protein to be tethered to the surface of these particles. Once tethered, IL-1ra maintains its bioactivity and actively targets synoviocytes, cells crucial to the OA pathology. This binding happens in an IL-1-dependent manner. Furthermore, IL-1ra-tethered particles are able to inhibit IL-1beta-induced NF-kappaB activation. These studies show that this particle system has the potential to deliver IL-1ra to arthritic joints and that it has potential for localizing/targeting drugs to inflammatory cells of interest as a new way to target OA drug treatments.

The use of dense CO2 in polymer processing can provide a response to the need for more environmentally-friendly industrial processes. Products with high-purity, sterility, and porosity can be achieved using dense gas technology (DGT). Currently, DGT has been used in different aspects of polymer processing including polymerization, micronization, and impregnation. Due to its solubility in polymers, CO2 can penetrate and plasticize polymers, while impregnating them with low-molecular weight CO2 -soluble compounds. Biodegradable polymers and other medical-grade polymers have benefited from the application of DGT. Dense CO2 processing properties of inertness, non-toxicity, and affinity for various therapeutic compounds are specifically advantageous to the medical and biomedical industries. In this work, the different applications of DGT in polymer processing are revised, then implemented. The polymerization of polycarbonate (PC) and polycaprolactone (PCL) in dense CO2 are presented. The syntheses of both polymers were successful and were aided by the use of dense CO2 . A multi-stage approach using dense CO2 as a sweep fluid to extract the PC polymerization by-product phenol is reported. Polycaprolactone was synthesized with varying temperatures and dense CO pressures, then impregnated with a CO2 -soluble therapeutic agent. The impregnated PCL acted as a drug reservoir with a drug-loading of 27wt% and a sustained drug release profile was observed for all samples over several days. Polymer blends of PC/PCL have potential industrial and biomedical applications both in vivo and in vitro. The applicability of PCL can be extended by enhancing its mechanical properties by creating a bio-blend with a stronger polymer such as PC. In this work, PC/PCL nonporous and porous blends were produced. Three novel dense CO2 blending techniques were used. The macroporous PC/PCL blend was impregnated with a therapeutic agent using CO2 as the carrier. A drug loading of 20wt% was achieved and sustained drug release was observed over 3 days. The applicability of dense CO2 in polymer processing was further demonstrated by sterilizing macroporous PC/PCL blends and soft hydrogels with dense CO2 . The PC/PCL blends and hydrogels were inoculated with vegetative bacteria and bacterial endospores. Industrial standard sterilization levels were achieved.