Úlceras são alterações que ocorrem na integridade da pele como consequência de lesões diversas, constituindo a dificuldade de sua cura um grave problema de saúde pública. A fototerapia com laser de baixa intensidade (LLLT), através de seus efeitos biomoduladores, vem sendo apontada como uma técnica prática, rápida e eficaz para esses casos. Entretanto, aplicações de LLLT podem, em alguns casos, estimular a proliferação de microrganismos patogênicos presentes na lesão, resultando numa piora da infecção e maior retardo no processo de reparo. Nesses casos, o uso de quimioterapia fotodinâmica antimicrobiana (PACT) pode ser uma alternativa. O presente estudo testou a eficácia da PACT com Ftalocianina Cloro-Alumínio (FC-ClAl) e da LLLT na inativação de microrganismos, com uma dose energética adequada para não prejudicar o processo de cicatrização. Em biofilmes de P. aeruginosa e S. aureus previamente cultivados por um período de 24 h em microplacas de 24 e 96 poços, realizou-se etapa única de aplicação da fototerapia LLLT e PACT com 4 diferentes formulações para inativação de microrganismos: formulação vazia (ausência de fármaco fotossensível FV), formulação catiônica vazia (com alteração em sua polaridade FCV), formulação aniônica com fármaco fotossensível (apenas Ftalocianina Cloro-alumínio FC-ClAl FAPc), formulação catiônica com fármaco fotossensível (FC-ClAl + formulação com polaridade alterada FCPc). Foram feitas análises quantitativas através da contagem de células viáveis e medidas de absorbância em leitora de ELISA com sal tetrazólio, 3-(4,5-dimethylthiazol-2-yl)-2,5-difenil brometo de tetrazólio (MTT), associado. Os dados obtidos foram comparados através de análise de variância (ANOVA) com nível de confiança de 95%. Os resultados obtidos permitiram concluir que a PACT com FC-ClAl sozinha (FAPc) não apresenta ação bactericida satisfatória sobre a P. aeruginosa e a S. aureus, mostrando resultados estimulatórios a esses microrganismos quando comparada às outras 3 formulações utilizadas. A ação antimicrobiana só foi observada ao se ter a associação da PACT Ftalocianina cloro-alumínio com a formulação catiônica (FCPc), a qual mostrou intensa interação com os biofilmes microbianos, principalmente com a S. aureus, mesmo na ausência de Ftalocianina (FCV). / Ulcers are changes on the skin integrity as a consequence of several lesions, and its cure represents a serious public health problem. Phototherapy based on low level laser therapy (LLLT), through its biomodulatory effects, has been pointed as a fast, practical and effective therapy for these cases. However, LLLT applications may, in some cases, stimulate pathogenic microorganisms proliferation present in the lesion, resulting in a worst infection and longer delay on the healing process. For such cases the use of Photodynamic Antimicrobial Chemotherapy (PACT) can be an alternative. The present study tested the PACT effectiveness with a phthalocyanine-derived photosensitizer and LLLT on microorganism inactivation, with an adequate energy dose in order to not damage all the healing process. On P. aeruginosa and S. aureus mature biofilms, previously cultivated for a period of 24 h in 24 and 96 wells-plate, a single application of phototherapy based on LLLT and PACT to inactivate bacteria was performed, with four different formulations: blank formulation (FV - no photosensitive drug), cationic empty formulation (FCV - formulation with an inverted polarity), formulation with anionic photosensitive drug (FAPc - only Chloro-aluminum Phthalocyanine) and cationic formulation with photosensitive drug (FCPc - Chloro-aluminum Phthalocyanine associated with an inverted polarity formulation). Quantitative analyses were performed through the counting of colony forming units (CFU) and the absorbance analysis with MTT associated. The data were compared through variance analysis test (ANOVA), with a confidence level of 95%. The results showed that PACT with Chloro-aluminum Phthalocyanine itself does not present satisfactory bactericidal effect against P. aeruginosa and S. aureus. This photosensitizer (FAPc) presented a microorganism stimulatory action when compared with the other three formulations used. The bactericidal effect was seen only with the PACT with cationic formulation association, which demonstrated an intense interaction with microbial biofilms, especially with S. aureus, even in the absence of Phthalocyanine (FCV).

Submitted by Nadir Basilio (nadirsb@uninove.br) on 2018-06-15T14:58:15Z No. of bitstreams: 1 Vinicius de Oliveira Cardoso.pdf: 848877 bytes, checksum: fe763aa5d3e08d692e2c53a7d7bb14cb (MD5) / Made available in DSpace on 2018-06-15T14:58:15Z (GMT). No. of bitstreams: 1 Vinicius de Oliveira Cardoso.pdf: 848877 bytes, checksum: fe763aa5d3e08d692e2c53a7d7bb14cb (MD5) Previous issue date: 2015-12-02 / The skeletal muscle cells are constant target for damage the exercise, direct trauma, inflammatory processes, among others. In order to contain or reset the loss of muscle mass, begins a highly organized repair process with activation, proliferation and differentiation of satellite cells. The use of phototherapy resources that can promote faster and efficient repair as the Low Level Laser Therapy (LLLT) has shown good results in the regeneration of skeletal muscle. The use of herbal medicines has also been described in the literature and has shown promising results with regard to tissue repair. The objective of the study was to evaluate the effects of treatment with LED on cell viability, Nitric Oxide (NO) synthesis and total protein dosage in C2C12 muscle cells cultured with Melaleuca armillaris extract in differentiation medium. We analyzed eight experimental groups: (1) Control C2C12; (2) LED 0,2J; (3) LED 2,0J; (4) LED 4,0J; (5) 1% Melaleuca; (6) Melaleuca 1% + LED 0,2J; (7) Melaleuca 1% + LED 2,0J; (8) Melaleuca 1% + LED 4,0J. Cells received Melaleuca extract at a concentration of 1.0% (v/v) and were irradiated with infrared LED (850nm, 30mW power for 7, 67 and 134 seconds at full power 0,2J, and 2,0J 4,0J, respectively) according to the group. Cell viability was assessed by MTT method, the synthesis of NO by the Griess method and total protein determination was performed using the Bradford method after periods of 1, 2 and 3 days of incubation. The results showed that cell viability increased TLED the three periods energies and tested without changing the total concentration of protein and NO. Since the herbal remedy promoted a significant reduction in cell viability compared to control small a reduction in the dosage of NO after 24 hours and no change in the protein assay. However, the combined use of the two resources, the energy value of 0.2 and showed viability 2,0J, NO and protein similar to the group treated only with 1% Melaleuca a tendency to increase in these levels in the group irradiated with 2,0J energy. However, the group associated 4,0J showed a growth recovery in cell viability in the three periods analyzed and behavior similar to nitric oxide and total protein compared to the control. In conclusion, the TLED positively modulated the proliferation of C2C12 cells without deterioration in nitric oxide synthesis and total protein, while incubation with associated or not to TLED Melaleuca needs more specific analyzes to elucidate their contribution in this context. / As células do músculo esquelético sofrem constantes lesões provocadas por exercício, traumas diretos, processos inflamatórios entre outros. A fim de conter ou repor a perda de massa muscular, inicia-se um processo de reparo altamente organizado com ativação, proliferação e diferenciação das células satélites. A utilização de recursos fototerápicos que possam promover um reparo mais rápido e eficiente como o Laser de Baixa Potência (LBP) tem apresentado bons resultados na regeneração do músculo esquelético. O uso de fitoterápicos também tem sido descrito na literatura e tem evidenciado resultados promissores no que diz respeito ao reparo tecidual. Assim, o objetivo do estudo foi avaliar os efeitos do tratamento com LED sobre a viabilidade celular, síntese de Óxido Nítrico (NO) e dosagem total de proteínas em células musculares C2C12 cultivadas com extrato de Melaleuca armillaris em meio de diferenciação. Foram analisados 8 grupos experimentais, sendo: (1) Controle C2C12; (2) LED 0,2J; (3) LED 2,0J; (4) LED 4,0J; (5) Melaleuca 1%; (6) Melaleuca 1%+LED 0,2J; (7) Melaleuca 1%+LED 2,0J; (8) Melaleuca 1%+LED 4,0J. As células receberam extrato de Melaleuca na concentração de 1,0% (v/v) e foram irradiadas com LED Infravermelho (850nm, potência de 30mW) por 7, 67 e 134 segundos, com energia total de 0,2J, 2,0J e 4,0J, respectivamente de acordo com o grupo. A viabilidade celular foi avaliada pelo método de MTT, a síntese de NO pelo método de Griess e a dosagem total de proteínas foi feita utilizando o método de Bradford após os períodos de 1, 2 e 3 dias de incubação. Os resultados demonstraram que a TLED aumentou a viabilidade celular nas três energias e períodos testados sem alterar a concentração de proteína total e NO. Já o recurso fitoterápico promoveu uma grande redução da viabilidade celular comparada ao controle, pequena redução na dosagem de NO após 24h e nenhuma alteração na dosagem de proteína. Contudo, o uso associado dos dois recursos, na energia de 0,2 e 2,0J apresentaram valor de viabilidade, NO e proteína semelhante ao grupo tratado somente com Melaleuca 1% com uma tendência no aumento destes níveis no grupo irradiado com 2,0J de energia. Entretanto, o grupo 4,0J associado evidenciou uma retomada de crescimento na viabilidade celular nos três períodos analisados e comportamento semelhante para óxido nítrico e proteína total comparados ao controle. Em conclusão, o TLED modulou positivamente a proliferação das células C2C12 sem apresentar alterações na síntese de óxido nítrico e proteína total, enquanto que a incubação com Melaleuca associada ou não ao TLED necessita de análises mais específicas para elucidar sua contribuição neste contexto.

Submitted by Nadir Basilio (nadirsb@uninove.br) on 2018-07-18T21:12:26Z No. of bitstreams: 1 Carla Bernardo Soldera.pdf: 1125219 bytes, checksum: a9bf43bd0d44898b4a48ec77b3f45001 (MD5) / Made available in DSpace on 2018-07-18T21:12:26Z (GMT). No. of bitstreams: 1 Carla Bernardo Soldera.pdf: 1125219 bytes, checksum: a9bf43bd0d44898b4a48ec77b3f45001 (MD5) Previous issue date: 2017-12-15 / Peripheral nerve lesions (LNP) do not clinically present a risk of death to the individual but may result in motor and sensory disturbances altering the function of the affected limb. Phototherapy using low level laser has demonstrated positive effects for the nervous and muscle repair process after different types of injury and little is known about the effects of light emitting diode (LED) therapy. Objective: To analyze the effects of LED on the nervous and muscular repair of Wistar rats after sciatic nerve crush injury. Methodology: 85 Wistar rats, weighing 200-250g, in 5 groups: Control: without any procedure; Injury: carried out only the crushing of the Left Sciatic Nerve (LSN); Injury + LEDn: LSN crushing and LED irradiation in the area corresponding to the nerve injury; Injury + LEDmm: LSN and LED crushing in Tibial Anterior muscle; Injury + LEDn + LEDmm: NSE crushing and LED irradiation in the area corresponding to nerve injury and muscle. The application of the LED in the nervous region was performed with the following parameters: wavelength of 808nm, beam area 1 cm2, average power 40Mw, power density 0.04 W/cm2, energy density 0.8 J/cm2, energy per point 0.8J , total of points 4, time per point 20sec, total time 80sec, energy per point 3.2J and in muscle region was used wavelength of 808nm, beam area 1 cm2, average power 40Mw, power density 0.04 W/ cm2, density of energy 0.4 J/ cm2, energy per point 0.4J, total of points 8, time per point 10sec, total time 80sec, energy per point 3.2J. At the end of the experimental periods, the gait analysis and the mechanical hyperalgesia test were performed. At the end of the experimental periods, gait analysis was performed using the Sciatic Function Index (IFC), as well as the analysis of mechanical hyperalgesia using the von Frey test using the pressure analgesimeter with transducer. After the euthanasia of the animals, the tibial muscles, left and right, were removed and weighed in a semi-analytical balance to determine the degree of muscular atrophy and the muscle mass ratio was calculated. Result: After the IFC, within 7 days, all groups treated with LED showed an improvement in gait compared to the lesion group. The group LEDn was the one that presented the best result compared to the control group. After 14 days, the group LEDn and LEDnm presented similar values to the control group. Regarding the muscular atrophy index, in the 7-day period, all the groups treated with LED showed a decrease of the index in relation to the Control group. In 14 days, the LED groups showed an increase in relation to the Injury group. At 21 and 28 days, the injured groups showed a decrease in relation to the Control group. Only the LEDnm group showed a decrease compared to the Injury group. Regarding mechanical hyperalgesia, the results showed that in 7 days, the LEDn group was the one that presented the best result compared to the control group. At 14 days, the LEDn and LEDm groups showed an increase in the threshold, requiring a greater pressure to promote an allergic response compared to the control group, making them more resistant to the stimuli. At 28 days, all lesioned and treated groups showed an increase in hyperalgesia in relation to the control group. Conclusion: We can conclude that LED increased gait functionality assessed by IFC after 1 and 2 weeks post LNP, especially when it was used in the nerve region associated or not to the muscle region, induced an increase in muscle mass in relation to the animals that did not receive treatment in the period of 2 weeks post LNP and in the 2 week period post LNP provided an increase in the pain threshold compared to the control group, requiring a nociceptive stimulus of greater intensity to generate the pain stimulus indicating a better recovery. / As lesões nervosas periféricas (LNP) não apresentam clinicamente um risco de morte ao indivíduo, porém podem resultar em distúrbios motores e sensoriais alterando a funcionalidade do membro afetado. A fototerapia utilizando laser de baixa potência (LBP) tem demonstrado efeitos positivos para o processo de reparo nervoso e muscular após diferentes tipos de lesão e pouco se conhece a respeito dos efeitos da terapia com diodo emissor de luz (LED, do inglês light emitting diode). Objetivo: Analisar os efeitos do LED sobre o reparo nervoso e muscular de ratos Wistar pós lesão por esmagamento do nervo ciático. Metodologia: foram utilizados 85 ratos Wistar, pesando 200-250g, em 5 grupos: Controle: sem nenhum procedimento; Lesão: realizado apenas o esmagamento do Nervo Ciático Esquerdo (NCE); Lesão+LEDn: esmagamento do NCE e irradiação LED na área correspondente à lesão nervosa; Lesão+LEDm: esmagamento do NCE e LED no músculo Tibial Anterior; Lesão+LEDnm: esmagamento do NCE e irradiação LED na área correspondente à lesão nervosa e músculo. A aplicação do LED em região nervosa foi realizada com os seguintes parâmetros: comprimento de onda de 808nm, área do feixe 1cm2, potência média 40Mw, densidade de potência 0.04W/ cm2, densidade de energia 0.8 J/cm2, energia por ponto 0.8J, total de pontos 4, tempo por ponto 20seg, tempo total 80seg, energia por ponto 3.2J e em região muscular foi utilizado comprimento de onda de 808nm, área do feixe 1cm2, potência média 40Mw, densidade de potência 0.04W/ cm2, densidade de energia 0.4 J/cm2, energia por ponto 0.4J, total de pontos 8, tempo por ponto 10seg, tempo total 80seg, energia por ponto 3.2J. Ao término dos períodos experimentais, foi realizada a análise de marcha utilizando o Índice Funcional Ciático (IFC), bem como a análise da hiperalgesia mecânica através do teste de von Frey utilizando o analgesímetro de pressão com transdutor. Após a eutanásia dos animais os músculos Tibial Anterior direito e esquerdo foram removidos e pesados em uma balança semi-analítica para determinação do grau de atrofia muscular sendo calculada a relação de massa muscular. Resultado: Após a realização do IFC, no período de 7 dias, todos os grupos tratados com LED apresentaram uma melhora da marcha em relação ao grupo Lesão. O grupo LEDn foi o que apresentou o melhor resultado comparado ao grupo controle. Após 14 dias, o grupo LEDn e LEDnm apresentaram valores semelhantes ao grupo controle. Já em relação ao índice de atrofia muscular, no período de 7 dias, todos os grupos tratados com LED demonstraram uma diminuição do índice em relação ao grupo Controle. Em 14 dias, os grupos LED demonstraram um aumento em relação ao grupo Lesão. Em 21 e 28 dias, os grupos lesionados demonstraram uma diminuição em relação ao grupo Controle. Apenas o grupo LEDnm apresentou uma diminuição em relação ao grupo Lesão. No que diz respeito a hiperalgesia mecânica, os resultados obtidos demonstraram que em 7 dias, o grupo LEDn foi o que apresentou o melhor resultado comparado ao grupo controle. Em 14 dias, os grupos LEDn e LEDm apresentaram um aumento no limiar sendo necessário uma pressão maior para promover uma resposta álgica comparados ao grupo controle, tornando-os mais resistentes aos estímulos. Em 28 dias todos os grupos lesionados e tratados apresentaram um aumento da hiperalgesia em relação ao grupo controle. Conclusão: O LED aumentou a funcionalidade da marcha avaliada pelo IFC após 1 e 2 semanas pós LNP, especialmente quando foi usado na região nervosa associada ou não à região muscular, induziu um aumento na massa muscular em relação aos animais que não receberam tratamento no período de 2 semanas pós LNP e proporcionou um aumento no limiar álgico comparado ao grupo controle no período de 2 semanas pós LNP, sendo necessário um estímulo nociceptivo de maior intensidade para gerar o estímulo doloroso indicando uma melhor recuperação.

La synthèse contrôlée de nanoparticules métalliques (NPM) selon des morphologies et dimensions particulières est un domaine de recherche interdisciplinaire en raison des nouvelles propriétés physiques variées, riches et complexes des NPM. Ces propriétés sont principalement régies par les oscillations collectives des électrons de conductions appelées « plasmons ». Ce phénomène se traduit optiquement par une sensibilité des NPM au moindre changement d’indice de réfraction par déplacement de leur bande de résonance plasmon. Ce phénomène en fonction de la morphologie des NPM est mis à profit dans applications assez modernes telles que la photothérapie contre le cancer et l’élaboration de capteurs ultrasensibles basés sur la Résonance Plasmon de Surface (SPR) ou sur la Spectroscopie d’Exaltation Raman de Surface (SERS). La sensibilité des NPM en tant que capteurs est directement liée à la nature chimique et cristalline du métal mais également à leur capacité à adsorber les molécules cibles, à absorber ou/et confiner et exalter la lumière incidente. Cette dernière propriété est généralement d’autant plus remarquable que la distance séparant les NPM est petite. Ainsi, le contrôle de la taille, forme et densité des NPM présente un intérêt majeur et les travaux visant à développer de nouvelles méthodes de fabrication ou de nano-structuration sont toujours d’actualité. D’ailleurs, la fabrication de nanoparticules métalliques (NPM) uniformes se fait principalement par synthèse colloïdale particulièrement par « seed mediated growth ». En revanche, cette méthode présente toujours certaines limitations dans le temps de préparation et la contrôle de taille et de forme. Dans ce contexte, nous avons, dans cette thèse, développé une nouvelle méthode de fabrication de nanoparticules métalliques (NPM) de différentes formes. Le principe consiste à structurer un polymère (PMMA) sous forme d’un film nanoporeux et d’utiliser les nanopores comme réacteur de synthèse de NPM. C'est ainsi que l’objectif de cette thèse était d’exploiter la méthode de fabrication ainsi proposée afin d’élaborer de nouveaux nano-capteurs de détection basés sur le SERS. Les travaux dans le cadre de cette thèse ont été réparties sur trois grands volets : Le premier consiste à étudier le mécanisme de synthèse afin d’optimiser le processus de formation des structures métalliques uniformes. Le 2ème vise à faire évoluer la forme des NPM en jouant sur les paramètres de synthèse. En parallèle à ces deux volets, une tâche importante a été consacrée à l’analyse morphologique en utilisant les techniques d’analyses structurales, et à la détermination et la modélisation des réponses optiques de ces NPMs notamment par la technique d’ellipsométrie spectroscopique / Controlled synthesis of metallic nanoparticles (MNPs), according to particular morphologies and dimensions, is an interdisciplinary field of research because of the new, varied, rich and complex physical properties of MNPs. These properties are mainly governed by the collective oscillations of conduction electrons called plasmons. This phenomenon is optically reflected by the sensitivity of the MNPs to the change in the surrounding refractive index and by the shift of their plasmon resonance band. This feature, according to the morphology of MNPs, is used in fairly modern applications such as cancer phototherapy and the development of the ultrasensitive sensors based on Surface Plasmon Resonance (SPR) or Surface Enhanced Raman Spectroscopy (SERS). The sensitivity of MNPs as sensors is not only directly related to the chemical and crystalline nature of the metal but also to their ability to adsorb target molecules, absorb and/or confine and enhance incident light. This last property is generally more remarkable as the distance separating the MNPs is small. Thus, the control of the size, shape and density of the MNPs is of major interest. Therefore, the development of new synthesis methods of MNPs is still relevant. Moreover, the fabrication of uniform metallic nanoparticles is mainly achieved by colloidal synthesis particularly by "seed mediated growth". On the other hand, this method always has certain limitations in the preparation time and the control of the size and shape. In this context, we have, in this thesis, developed a new fabrication method of MNPs of different shapes. The idea is to structure a polymer (PMMA) in the form of a nanoporous film and to use the nanopores as synthesis reactor for MNPs. Thus, the objective of this thesis was to investigate the proposed synthesis method in order to develop new detection nanosensors based on SERS phenomenon. The work in this thesis has been divided into three main parts: the first is to study the synthesis mechanism in order to optimize the formation process of uniform metallic structures. The second aims to change the shape of the MNPs by playing on the parameters of synthesis. In parallel with these two aspects, an important task was devoted to morphological analysis using structural analysis techniques, and to the determination and the modelling of the optical responses of these MNPs particularly by the technique of spectroscopic ellipsometry

Einleitung: Fibroblasten bilden essentielle Komponenten des Bindegewebes und reagieren auf Bestrahlung mit langwelligem Licht. In der Zellkultur lässt sich durch Lichtsignale eine gerichtete Migration (= Phototaxis) induzieren. Da die Migration von Fibroblasten eine zentrale Rolle für die Wundheilung und Regeneration des Bindegewebes spielt, hat die Phototherapie mit langwelligem, nicht-thermischem Licht besondere klinische Bedeutung erlangt. Eindeutige Vorgaben für phototherapeutische Anwendungsparameter existieren bisher jedoch nicht. Fragestellung: Frühere Versuchsanordnungen zur vitalmikroskopischen Untersuchung der Phototaxis von 3T3-Fibroblasten arbeiteten in geschlossenen Kulturflaschen mit Latex- Kügelchen als Lichtquellen, die von externen Strahlungsquellen aktiviert wurden. Die vorliegende Arbeit beschreibt die Entwicklung einer faseroptischen Anordnung mit freier Positionierbarkeit in der offenen Kulturschale. Die primäre Fragestellung war die Eignung der Methode zur Erstellung eines Aktionsspektrums für Phototaxis photoresponsiver, adhärent wachsender Zellen. Material und Methoden: Die Versuche wurden mit NIH-3T3-Zellen der Schweizer Maus durchgeführt. Um die Ergebnisse nicht durch Fremd-Chromophore zu verfälschen, wurden native Zellen ohne Färbemethoden vitalmikroskopisch untersucht. Eine speziell entwickelte Faseroptik und LED-Lichtquellen mit verschiedenen Wellenlängen ermöglichten die direkte Einbringung und Positionierung der Lichtsignale auf dem Boden der Kulturschale. Ein wissenschaftliches Bildbearbeitungsprogramm wurde durch ein Plug-In so modifiziert, dass die Bewegungs- und Zeitparameter halbautomatisch erfasst werden konnten. Ergebnisse: Bei 18 von 44 Langzeitversuchen konnte eindeutiges phototaktisches Verhalten mit Zellkontakt zur Lichtquelle induziert werden. In 16 Fällen kam es zur migratorischen Annäherung und in 10 Fällen zu keiner Reaktion bzw. einer diskret negativen Phototaxis. Das positive phototaktische Verhalten der beiden reagierenden Gruppen war hochsignifikant, der zweiseitige p-Wert des Binomialtests beträgt 0,000388. Bei 77,3 % der Versuche konnte positive Phototaxis demonstriert werden. Schlussfolgerungen: Das neu entwickelte Verfahren eignet sich zur Untersuchung einer Phototaxis und kann damit prinzipiell zur Erstellung von phototaktischen Aktionsspektren eingesetzt werden. Im Vergleich zu bisherigen Methoden können die Bestrahlungsstärken direkt am Lichtwellenleiter gemessen und unerwünschte Fremdkörper-induzierte Wechselwirkungen eliminiert werden. Durch die freie Positionierbarkeit der Lichtquelle in der Kulturschale können die zu beobachtenden Zellen beliebig ausgewählt werden.:INHALTSVERZEICHNIS IV ABBILDUNGSVERZEICHNIS VII TABELLENVERZEICHNIS IX ABKÜRZUNGSVERZEICHNIS X 1. EINLEITUNG 1 2. DEFINITIONEN UND STAND DER FORSCHUNG 5 2.1 LICHT 5 2.1.1 Sonnenlicht 5 2.1.2 Licht in der Physik 5 2.1.3 Licht in der Biologie 6 2.1.3.1 Taxis 7 2.1.4 Licht in der Medizin 8 2.1.4.1 Historischer Überblick 8 2.2 PHOTOBIOLOGIE VON ROT UND NAHINFRAROT 10 2.2.1 Photochemische Grundlagen 10 2.2.2 Haut 11 2.2.2.1 Aufbau und Funktion 11 2.2.2.2 Optische Eigenschaften 12 2.2.3 Fibroblasten 13 2.2.4 Zellmigration 15 2.2.5 Mitochondrien 16 2.3 PHOTOTAXIS BEI 3T3-FIBROBLASTEN 17 3. FRAGESTELLUNG 23 4. MATERIAL UND METHODEN 25 4.1 GERÄTE, LABORMATERIALIEN UND SOFTWARE 25 4.2 ZELLMATERIAL UND KULTURBEDINGUNGEN 25 4.3 ZELLPRÄPARATION 27 4.4 VERSUCHSAUFBAU 27 4.5 SHUTTER-SIMULATION DER OBJEKTBELEUCHTUNG 32 4.6 ZUFUHR VON DESTILLIERTEM WASSER 33 4.7 VERSUCHSABLAUF 33 4.8 VERMESSUNG DES BEWEGUNGSVERHALTENS 35 4.9 STATISTISCHE BERECHNUNG 36 5. ERGEBNISSE 37 5.1 AUSWAHLKRITERIEN FÜR GÜLTIGE VERSUCHE 37 5.2 GRUPPENEINTEILUNG DER GÜLTIGEN VERSUCHE 38 5.2.1 Die Gruppe "Touchdown" (TD) 38 5.2.2 Die Gruppe "Annäherung/Closer" (CL) 39 5.2.3 Die Gruppe "still/entf./no reaction" (NO) 39 5.2.4 Zusammenfassung des Gruppenverhaltens 40 5.3 GRAFISCHE DARSTELLUNGEN DER AUSGEWERTETEN VERSUCHE 41 5.4 PRIMÄRE FRAGESTELLUNG: PHOTOTAKTISCHE REAKTION 49 5.5 FRAGESTELLUNG 2: EINFLUSS DER MIGRATIONSMODALITÄT 49 5.6 EINFLUSS VON WELLENLÄNGE UND LICHTMODULATION 51 5.6.1 Fragestellung 3: Einfluss der Wellenlänge 51 5.6.2 Fragestellung 4: Einfluss der Pulsationsfrequenz 52 5.7 FRAGESTELLUNG 5: ROLLE DER AUSGANGSPOSITION 53 5.8 LOKOMOTORISCHE PARAMETER 54 5.8.1 Fragestellung 6: Zurückgelegte Wegstrecke 54 5.8.2 Fragestellung 7: Migrationsgeschwindigkeit 56 5.9 FRAGESTELLUNG 8: EINFLUSS DER VITALITÄT 57 5.9.1 Definition der mittleren Vitalität vitmean 57 5.9.2 Definition der relativen Vitalität vitrel 57 5.9.3 Die relative Vitalität vitrel der Zellen FBc, FB1 und FB2 58 5.9.4 Die mittlere Vitalität vitmean in den Versuchsgruppen 59 5.9.5 Die relative Vitalität vitrel des zentralen Fibroblasten 60 5.10 ATYPISCHES ZELLVERHALTEN 61 5.10.1 Atypisches Verhalten in Versuchen mit normalen 3T3-Zellen 61 5.10.1.1 Hohe Geschwindigkeit und große Wegstrecke 61 5.10.1.3 "Überfall" eines Fibroblasten 63 5.10.1.2 Zentraler Fibroblast migriert unter den Lichtwellenleiter 64 5.10.2 Atypisches Verhalten bei frischen humanen Monozyten 66 6. DISKUSSION 68 6.1 ERGEBNISSE 68 6.1.1 Primäre Fragestellung: Phototaktische Reaktion 68 6.1.2 Fragestellung 2: Einfluss der Migrationsmodalität 70 6.1.3 Fragestellung 3: Einfluss der Wellenlänge 71 6.1.4 Fragestellung 4: Einfluss der Pulsationsfrequenz 74 6.1.5 Fragestellung 5: Rolle der Ausgangsposition 78 6.1.6 Fragestellung 6: Zurückgelegte Wegstrecke 79 6.1.6.1 Differenz Startposition - Minimalposition zum LWL 79 6.1.6.2 Insgesamt zurückgelegte Wegstrecke 80 6.1.7 Fragestellung 7: Migrationsgeschwindigkeit 80 6.1.8 Fragestellung 8: Einfluss der Vitalität 81 6.1.9 Atypisches Zellverhalten 83 6.1.9.1 Versuche mit 3T3-Zellen 83 6.1.9.1.1 Hohe Geschwindigkeit und große Wegstrecke 83 6.1.9.1.2 "Überfall" eines Fibroblasten 84 6.1.9.1.3 Phototaxis bei hyperosmotischem Stress 85 6.1.9.2 Atypisches Verhalten bei frischen humanen Monozyten 86 6.1.10 Zusätzliche Fragestellungen 87 6.1.10.1 Wie lange ist die maximale Versuchsdauer im offenen System 88 6.1.10.2 Spielt der Aspekt der potentiellen Verkeimung eine relevante Rolle? 88 6.1.10.3 Spielt die Dimension der Lichtquelle eine objektivierbare Rolle 88 6.1.10.4 Kann die Bestrahlungsstärke gemessen anstatt geschätzt werden 89 6.1.10.5 Können Rückschlüsse auf das "Auge der Zelle" gezogen werden? 90 6.2 SCHLUSSFOLGERUNG 93 6.3 AUSBLICK 94 7. ZUSAMMENFASSUNG 96 7.1 SUMMARY 97 8. LITERATURVERZEICHNIS 98 9. ANLAGEN 117 9.1 LABORGERÄTE UND MATERIALIEN 117 9.1.1 Mikroskope 117 9.1.2 Software: 117 9.1.3 Geräte: 118 9.1.4 Verbrauchsmaterialien 118 9.1.5 Medien, Puffer, Lösungen 119 9.2 EIGENE GERÄTSCHAFTEN 120 9.2.1 Frequenzgenerator 120 9.2.2 Halbleiter-Lichtquellen 121 9.2.2.1 Modulierbare Lichtquelle 121 9.2.2.2 Kohärente Lichtquelle 122 9.2.2.3 Photon Micro-Light LED-Lichtquellen mit Pulsmodus f = 1Hz 124 9.2.2.4 Bestrahlungsstärken der verwendeten Lichtquellen 124 9.2.3 Systemträger 125 9.2.4 LWL und Optokoppler 126 9.2.5 Modifizierte Microsoft-Maus 126 9.2.6 Eigene Software 127 10. DANKSAGUNG 128 11. EIDESSTATTLICHE ERKLÄRUNG 130 / Background: Fibroblasts are essential constituents of connective tissue and react upon irradiation with long-wavelength light. In cell culture, directed migration (= phototaxis) can be induced by light stimuli. Fibroblast migration and activity play a central role for wound healing and connective tissue regeneration. In consequence, phototherapy with non-thermal, long wavelength light obtained increasing clinical importance. However, accepted guidelines for phototherapeutical treatment parameters are still lacking. Objective: Existing assays for microscopic observation of phototactic reaction of 3T3- fibroblasts in a live cell chamber use closed cell culture flasks with small light-scattering latex particles attached to the surface of the flask bottom prior to cell seeding, which can be illuminated by an external light source. The present work describes the development of a fiberoptic assembly providing free positioning of the light source in an open culture dish. The primary objective is the eligibility of this method for determination of a phototactic action spectrum for photoresponsive adherent cell species. Materials and Methods: Experiments were conducted using Swiss mouse NIH-3T3-cells. Native cells without staining were used for elimination of potential dye-induced cell-light interferences. A light microscope with field illumination shutter simulation and live cell chamber was used in combination with a specially devised LED-light-fed fiberoptic assembly providing different wavelengths, which could be directly positioned on the inner bottom of the culture dish. A scientific image processing application was modified by a special plug-in for semi-automatic acquisition of cellular locomotion parameters and temporal data token. Results: A total of 44 experiments were conducted. 18 essays resulted in full phototactic reaction characterized by pseudopodium contact with the fiberoptic aperture, another 16 essays showed migratory approximation without direct contact with the light source. 10 essays displayed no reaction or discrete negative phototaxis. The positive phototaxis of the two responding groups was highly significant in the two-sided binomial test (p = 0.000388). For 77.3 % of the experiments positive phototaxis could be demonstrated. Conclusions: The newly developed assay is appropriate for the induction of phototactic behaviour and can be utilized for the determination of phototactic action spectra. In contrast to existing methods the irradiances can be measured directly at the aperture of the optical fiber and biasing foreign object-induced effects can be eliminated. Due to arbitrary positioning of the light source the cells can be chosen freely for examination.:INHALTSVERZEICHNIS IV ABBILDUNGSVERZEICHNIS VII TABELLENVERZEICHNIS IX ABKÜRZUNGSVERZEICHNIS X 1. EINLEITUNG 1 2. DEFINITIONEN UND STAND DER FORSCHUNG 5 2.1 LICHT 5 2.1.1 Sonnenlicht 5 2.1.2 Licht in der Physik 5 2.1.3 Licht in der Biologie 6 2.1.3.1 Taxis 7 2.1.4 Licht in der Medizin 8 2.1.4.1 Historischer Überblick 8 2.2 PHOTOBIOLOGIE VON ROT UND NAHINFRAROT 10 2.2.1 Photochemische Grundlagen 10 2.2.2 Haut 11 2.2.2.1 Aufbau und Funktion 11 2.2.2.2 Optische Eigenschaften 12 2.2.3 Fibroblasten 13 2.2.4 Zellmigration 15 2.2.5 Mitochondrien 16 2.3 PHOTOTAXIS BEI 3T3-FIBROBLASTEN 17 3. FRAGESTELLUNG 23 4. MATERIAL UND METHODEN 25 4.1 GERÄTE, LABORMATERIALIEN UND SOFTWARE 25 4.2 ZELLMATERIAL UND KULTURBEDINGUNGEN 25 4.3 ZELLPRÄPARATION 27 4.4 VERSUCHSAUFBAU 27 4.5 SHUTTER-SIMULATION DER OBJEKTBELEUCHTUNG 32 4.6 ZUFUHR VON DESTILLIERTEM WASSER 33 4.7 VERSUCHSABLAUF 33 4.8 VERMESSUNG DES BEWEGUNGSVERHALTENS 35 4.9 STATISTISCHE BERECHNUNG 36 5. ERGEBNISSE 37 5.1 AUSWAHLKRITERIEN FÜR GÜLTIGE VERSUCHE 37 5.2 GRUPPENEINTEILUNG DER GÜLTIGEN VERSUCHE 38 5.2.1 Die Gruppe "Touchdown" (TD) 38 5.2.2 Die Gruppe "Annäherung/Closer" (CL) 39 5.2.3 Die Gruppe "still/entf./no reaction" (NO) 39 5.2.4 Zusammenfassung des Gruppenverhaltens 40 5.3 GRAFISCHE DARSTELLUNGEN DER AUSGEWERTETEN VERSUCHE 41 5.4 PRIMÄRE FRAGESTELLUNG: PHOTOTAKTISCHE REAKTION 49 5.5 FRAGESTELLUNG 2: EINFLUSS DER MIGRATIONSMODALITÄT 49 5.6 EINFLUSS VON WELLENLÄNGE UND LICHTMODULATION 51 5.6.1 Fragestellung 3: Einfluss der Wellenlänge 51 5.6.2 Fragestellung 4: Einfluss der Pulsationsfrequenz 52 5.7 FRAGESTELLUNG 5: ROLLE DER AUSGANGSPOSITION 53 5.8 LOKOMOTORISCHE PARAMETER 54 5.8.1 Fragestellung 6: Zurückgelegte Wegstrecke 54 5.8.2 Fragestellung 7: Migrationsgeschwindigkeit 56 5.9 FRAGESTELLUNG 8: EINFLUSS DER VITALITÄT 57 5.9.1 Definition der mittleren Vitalität vitmean 57 5.9.2 Definition der relativen Vitalität vitrel 57 5.9.3 Die relative Vitalität vitrel der Zellen FBc, FB1 und FB2 58 5.9.4 Die mittlere Vitalität vitmean in den Versuchsgruppen 59 5.9.5 Die relative Vitalität vitrel des zentralen Fibroblasten 60 5.10 ATYPISCHES ZELLVERHALTEN 61 5.10.1 Atypisches Verhalten in Versuchen mit normalen 3T3-Zellen 61 5.10.1.1 Hohe Geschwindigkeit und große Wegstrecke 61 5.10.1.3 "Überfall" eines Fibroblasten 63 5.10.1.2 Zentraler Fibroblast migriert unter den Lichtwellenleiter 64 5.10.2 Atypisches Verhalten bei frischen humanen Monozyten 66 6. DISKUSSION 68 6.1 ERGEBNISSE 68 6.1.1 Primäre Fragestellung: Phototaktische Reaktion 68 6.1.2 Fragestellung 2: Einfluss der Migrationsmodalität 70 6.1.3 Fragestellung 3: Einfluss der Wellenlänge 71 6.1.4 Fragestellung 4: Einfluss der Pulsationsfrequenz 74 6.1.5 Fragestellung 5: Rolle der Ausgangsposition 78 6.1.6 Fragestellung 6: Zurückgelegte Wegstrecke 79 6.1.6.1 Differenz Startposition - Minimalposition zum LWL 79 6.1.6.2 Insgesamt zurückgelegte Wegstrecke 80 6.1.7 Fragestellung 7: Migrationsgeschwindigkeit 80 6.1.8 Fragestellung 8: Einfluss der Vitalität 81 6.1.9 Atypisches Zellverhalten 83 6.1.9.1 Versuche mit 3T3-Zellen 83 6.1.9.1.1 Hohe Geschwindigkeit und große Wegstrecke 83 6.1.9.1.2 "Überfall" eines Fibroblasten 84 6.1.9.1.3 Phototaxis bei hyperosmotischem Stress 85 6.1.9.2 Atypisches Verhalten bei frischen humanen Monozyten 86 6.1.10 Zusätzliche Fragestellungen 87 6.1.10.1 Wie lange ist die maximale Versuchsdauer im offenen System 88 6.1.10.2 Spielt der Aspekt der potentiellen Verkeimung eine relevante Rolle? 88 6.1.10.3 Spielt die Dimension der Lichtquelle eine objektivierbare Rolle 88 6.1.10.4 Kann die Bestrahlungsstärke gemessen anstatt geschätzt werden 89 6.1.10.5 Können Rückschlüsse auf das "Auge der Zelle" gezogen werden? 90 6.2 SCHLUSSFOLGERUNG 93 6.3 AUSBLICK 94 7. ZUSAMMENFASSUNG 96 7.1 SUMMARY 97 8. LITERATURVERZEICHNIS 98 9. ANLAGEN 117 9.1 LABORGERÄTE UND MATERIALIEN 117 9.1.1 Mikroskope 117 9.1.2 Software: 117 9.1.3 Geräte: 118 9.1.4 Verbrauchsmaterialien 118 9.1.5 Medien, Puffer, Lösungen 119 9.2 EIGENE GERÄTSCHAFTEN 120 9.2.1 Frequenzgenerator 120 9.2.2 Halbleiter-Lichtquellen 121 9.2.2.1 Modulierbare Lichtquelle 121 9.2.2.2 Kohärente Lichtquelle 122 9.2.2.3 Photon Micro-Light LED-Lichtquellen mit Pulsmodus f = 1Hz 124 9.2.2.4 Bestrahlungsstärken der verwendeten Lichtquellen 124 9.2.3 Systemträger 125 9.2.4 LWL und Optokoppler 126 9.2.5 Modifizierte Microsoft-Maus 126 9.2.6 Eigene Software 127 10. DANKSAGUNG 128 11. EIDESSTATTLICHE ERKLÄRUNG 130

Orientador: Aldo Eloizo Job / Resumo: As vantagens do uso de dispositivos ópticos na área das ciências da vida são amplamente exploradas, especialmente para o diagnóstico médico e protocolos de tratamento em uma prática de cuidados de saúde. Além disso, alguns pesquisadores têm atraído muita atenção ao desenvolvimento de materiais biocompatíveis e vestíveis para melhorar a segurança de dispositivos médicos, bem como para estabelecer novos procedimentos para monitorar a resposta de terapia e diagnóstico clínico. O presente trabalho tem como objetivo desenvolver uma membrana biocompatível-luminescente não invasiva para reduzir os erros mais comuns relatados em fototerapia convencional de luz azul para icterícia neonatal. Dentre estes erros destacam-se: intensidade de irradiância que chega ao recém-nascido bem como seu posicionamento frente a fonte de radiação e qualidade das lâmpadas dos aparelhos fototerápicos. Neste contexto, a membrana foi confeccionada como um filme de sensor de luz azul, fluorescente e colorimétrico a partir de polímeros: poli [2-metoxi, 5-(2'etilhexyloxy)-pfenilenovileno (MEH-PPV) em uma matriz de borracha natural. Para tal, as membranas de borracha natural (BN) foram obtidas utilizando o látex, extraído das árvores Hevea brasiliensis (clone RRIM 600), por casting, com posterior tratamento térmico em estufa. Em seguida, também por casting, a solução de MEH-PPV/BN, razão igual a 4000, foi depositada na membrana BN para fazer uma camada fina de material luminescente. A membrana de MEH-PPV/BN fo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The advantages of optical devices in the life sciences are widely exploited, especially for medical diagnosis and treatment protocols in a health care practice. In addition, some researchers have attracted much attention to development flexible and biocompatible materials to improve security of medical devices, as well as to establish new procedures for monitoring therapy response and clinical diagnosis. The present paper aims to develop a new noninvasive biocompatible-luminescent membrane to reduce the most common user errors with conventional blue-light phototherapy of neonatal jaundice. The membrane was design based on a polymer-based fluorescent and colorimetric blue-light sensor film. This material was based on poly[2-methoxy,5-(2'etilhexyloxy)-p-fenilenovileno (MEH-PPV) in a natural rubber matrix. Natural rubber membranes (BN) were obtained using latex from Hevea brasiliensis trees (clone RRIM 600) by casting, with the time and temperature of thermal treatment fixed on 65°C for 10h. Then, also by casting, MEH-PPV/NR solution, ratio equal to 4000, was deposited on NR membrane for make thin-layer of luminescent material. The MEH-PPV/NR membrane was submitted to the same conditions used for neonatal hyperbilirubinemia treatment (Blue light phototherapy, 40 µW/m2 /nm, 460nm). The proprieties of membranes were characterized by optical (UV-Vis, PL) and infrared (FTIR) spectroscopy confocal microscopy (MC), scanning electron microscopy (SEM) and atomic force microscopy (AFM) a... (Complete abstract click electronic access below) / Doutor

Orientador: Ana Liz Garcia Alves / Coorientador: Roberto Calderon Gonçalves / Banca: Monica de Oliveira Orsi Gameiro / Banca: Celso Antonio Rodrigues / Resumo: Este projeto teve como objetivo avaliar os efeitos da fototerapia na cicatrização do tendão usando diodos superluminosos fixados em 890nm. Foram induzidas lesões cirúrgicas de 0,2cm de largura x 0,5cm de comprimento, realizadas no segundo terço do Tendão Flexor Digital Superficial de 10 ovelhas saudáveis que foram divididos em dois grupos: grupo tratado com diodos superluminosos com o comprimento de onda acima mencionado e grupo controle, tratado com placebo. A Cinesioterapia foi realizada em ambos os grupos. Os exames ultrassonográficos Modo B e Doppler foram realizados durante os primeiros 14 dias após a cirurgia e, em seguida, nos dias 21 e 28, a fim de avaliar o processo de cicatrização do tendão. A biópsia foi realizada no dia 28 para avaliar a neovascularização e o padrão tendão de fibra no exame histopatológico. Ausência de claudicação e uma melhoria significativa (p < 0,05) na dor após palpação foram observadas no grupo tratado. Além disso, no modo B foi evidenciada uma redução significativa do edema (p < 0,05) nestes animais. Não foi encontrada diferença estatística em relação à evolução da lesão. Houve diferença histológica (p < 0,05) para a neovascularização no grupo tratado. Fototerapia com diodos superluminosos de 890nm minimiza os efeitos do processo inflamatório / Abstract: This project aimed to evaluate the effects of phototherapy on tendon healing using superluminous diodes set at 890nm. Surgical lesions were induced by 0.2 cm wide x 0.5 cm long, made in the second third of the superficial digital flexor tendon of 10 healthy sheep were divided into two groups: group treated with superluminous diodes with the wavelength mentioned above and control group treated with placebo. The Kinesiotherapy was performed in both groups. The B mode ultrasound examination and Doppler were performed during the first 14 days after surgery and then on days 21 and 28, to evaluate the healing of the tendon. A biopsy was performed on day 28 to evaluate neovascularization and tendon fiber pattern on histopathological examination. No lameness and a significant improvement (p <0.05) in pain after palpation were observed in the treated group. Furthermore, in the mode B was observed a significant reduction in edema (p <0.05) in these animals. No statistical difference was found in relation to the evolution of the lesion. Significant difference was seen (p <0.05) for neovascularization in the treated group. Phototherapy with 890nm superluminous diodes minimizes the effects of the inflammatory process / Mestre

La thérapie photo-dynamique (PDT) est une thérapeutique applicable à de nombreuses spécialités. Elle consiste en l'administration d'un photosensibilisateur qui se concentre dans un délai variable dans la lésion à traiter puis l'éclairage de la lésion (par une lumière de longueur d'onde déterminée par le spectre d'absorption du photosensibilisateur) qui conduit finalement à la destruction de la lésion [1]. Le but de mon projet d'étude est de faire l'étude et control des propriétés des membranes. nous allons utiliser des bactéries comme des membranes artificielles. Nous allons utiliser les molécules azobenzenique dans des milieux réels où il y'a des bactéries ou d'autres cellules vivantes. Des bactéries ont des impacts sur la santé humaine. plusieurs bactéries ont besoin de se déplacer vers des sites spécifiques. Le moyen de locomotion le plus commun est le moteur flagellaire. Les bactéries flagellaires ont un moteur rotatif ancré dans leur membrane qui transmet sa rotation à un long filament en forme d'hélice se trouvant à l'extérieur de la bactérie via un joint universel se nommant le crochet. De plus, les moteurs flagellaires jouent un rôle très important durant les infections bactériennes. En effet, les bactéries se déplacent souvent dans des milieux anisotropes, où les propriétés physiques dépendent de la direction. La motilité des bactéries (vitesse de nage) est définie par l'électro-conductivité de sa membrane. Si nous ajoutons des azobenzènes et si les azobenzène s'incorpore à la membrane (attachement à la surface ou pénétration dans la membrane) alors nous pouvons essayer de perturber les membranes avec la lumière en excitant les azobenzènes. Cela devrait nous permettre de de développer des nouvelles techniques de la photo-thérapie pour contrôler la motilité des bactéries ou d'autres cellules vivantes / Photodynamic therapy (PDT) is a therapy applicable to many medico-surgical specialties. It consists of the administration of a photosensitizer which concentrates with in a variable time in the lesion to be treated then the illumination of the lesion (by a light of wavelength determined by the absorption spectrum of the photosensitizer) which leads finally to thedestruction of the lesion [1]. The goal of my study project is to study and control the properties of membranes. we are going to use bacteria as artificial membranes. We will use azobenzene molecules in real environments where there are bacteria or otherliving cells. Bacteria have impacts on human health. several bacteria need to move tospecific sites. The most common means of locomotion is the flagellar motor. flagellar bacteria have a rotary motor anchored in their membrane which transmits its rotation to a long filament in the form of a helix lying outside the bacterium via a universal joint called the hook. In addition, flagellar motors play a very important role during bacterial infections. Indeed, bacteria often move in an isotropic media, where the physical properties depend on the direction. the motility of bacteria (swimming speed) is defined by the electro-conductivity of its membrane. If we add azobenzenes and if the azobenzenes become incorporated into the membrane (attachment to the surface or penetration into the membrane) then we can try to perturb the membranes with light by exciting the azobenzenes. This should allow us to develop new phototherapy techniques to control the motility of bacteria or other living cells

Current chemotherapeutics exhibit debilitating side effects as a result of their toxicity to healthy tissues. Reducing these side effects by developing chemotherapeutics with selectivity for cancer cells is an active area of research. Phototherapy is one promising modality for selective treatment, where drug molecules are “turned on” when irradiated with light, reducing damage to healthy tissues by spatially restricting the areas exposed to irradiation. A second approach to improve selectivity is to exploit the differences in cancerous versus healthy cells, such as increased metabolism and/or upregulation of cell surface receptors. Ruthenium(II) polypyridyl complexes are candidates for phototherapy due to their highly tunable photophysical and photochemical properties. The addition of strain to the metal center is a general approach used to render complexes susceptible to light-induced ligand loss. Upon ejection of a ligand, the Ru(II) center is capable of covalently binding biomolecules within cells to produce a cytotoxic effect. The ligands surrounding the metal center are amenable to chemical modification through the incorporation of pendent functional groups as chemical “handles”, allowing for different directing molecules to be attached. Nucleic acids are important targets for drug discovery, and the development of selective probes to either visualize or selectively damage nucleic acids within the cell is an ongoing area of research. Specifically, G-rich regions are abundant in the human genome, and the presence of G-quadruplexes in telomeres and promoter regions of oncogenes make them potential therapeutic targets. Ru(II) complexes are known to bind nucleic acids, and some have been shown to induce and/or stabilize G-quadruplex Structures. Multiple series of Ru(II) compounds have been synthesized and tested to improve the functional range for Ru(II) complexes for in vivo applications, where they act as “light switches” for DNA. These molecules are “off” when in an aqueous environment but turned “on” in the presence of DNA. Several hit compounds were identified that showed selectivity for specific G-quadruplex structures.

No description available.