Tissue engineering has emerged as a promising alternative to conventional orthopaedic grafting therapies. The general paradigm for this approach, in which phenotype-specific cells and/or bioactive growth factors are integrated into polymeric matrices, has been successfully applied in recent years toward the development of bone, ligament, and cartilage tissues in vitro and in vivo. Despite these advances, an optimal cell source for skeletal tissue repair and regeneration has not been identified. Furthermore, the lack of robust, functional orthopaedic tissue interfaces, such as the bone-ligament enthesis, severely limits the integration and biological performance of engineered tissue substitutes. This works aims to address these limitations by spatially controlling the genetic modification and differentiation of fibroblasts into a mineralizing osteoblastic phenotype within three-dimensional polymeric matrices. The overall objective of this project was to investigate transcription factor-based gene therapy strategies for the differentiation of fibroblasts into a mineralizing cell source for orthopaedic tissue engineering applications. Our central hypothesis was that fibroblasts genetically engineered to express Runx2 via conventional and biomaterial-mediated ex vivo gene transfer approaches will differentiate into a mineralizing osteoblastic phenotype. We have demonstrated that a combination of retroviral Runx2 overexpression and glucocorticoid hormone treatment synergistically induces osteoblastic differentiation and biological mineral deposition in primary dermal fibroblasts cultured in monolayer. We report for the first time that glucocorticoids induce osteoblastic differentiation in this model system by modulating the phosphorylation state of a negative regulatory serine residue (Ser125) on Runx2 through an MKP-1-dependent mechanism. Furthermore, we utilized these Runx2-genetically engineered fibroblasts to create mineralized templates for bone repair in vitro and in vivo. Finally, we engineered a heterogeneous bone-soft tissue interface with a novel biomaterial-mediated gene transfer approach. Overall, these results are significant toward the ultimate goal of regenerating complex, higher-order orthopaedic grafting templates which mimic the cellular and microstructural characteristics of native tissue. Cellular therapies based on primary dermal fibroblasts would be particularly beneficial for patients with a compromised ability to recruit progenitors to the sight of injury as result of traumatic injury, radiation treatment, or osteodegenerative disease.

Στην παρούσα διατριβή, μελετήθηκε η χρήση ελαστικών λιποσωμάτων στη διαδερμική χορήγηση υδατοδιαλυτών ουσιών και πραγματοποιήθηκαν επίσης μελέτες προ-μορφοποίησης αντιϋπερτασικών βιοδραστικών ενώσεων για διαδερμική χορήγηση. Αρχικά, πραγματοποιήθηκαν μελέτες της φυσιολογίας του δέρματος με τεχνικές μικροσκοπίας και μέτρησης της απώλειας ύδατος μέσω της επιδερμίδας (TEWL) με σκοπό να διαπιστωθεί η λειτουργία του φραγμού της κεράτινης στοιβάδας, καθώς και η ορθότητα χρήσης των σχετικών τεχνικών προετοιμασίας των δειγμάτων δέρματος που χρησιμοποιήθηκαν. Η οπτική μικροσκοπία ειδικά μας έδωσε πληροφορίες ως προς τη δομή της επιδερμίδας και ως προς τον πιθανό μηχανισμό μεταφοράς ουσιών μέσω της χρήσης λιποσωμάτων. Στη συνέχεια πραγματοποιήθηκε μελέτη και σύγκριση των διαφόρων φυσικοχημικών χαρακτηριστικών ελαστικών λιποσωμάτων που μπορεί να χρησιμοποιηθούν ως πρώτοι δείκτες για πρόγνωση της διαδερμικής απορρόφησης (in vivo) των υδρόφιλων βιοδραστικών ενώσεων. Ως μοντέλα υδρόφιλων βιοδραστικών ενώσεων χρησιμοποιήθηκαν οι φθορίζουσες χρωστικές καλσεΐνη και καρβοξυφλουορεσκεΐνη. Όλες οι λιποσωμικές διασπορές (τόσο τα συμβατικά λιποσώματα-CLs, όσο και τα ελαστικά λιποσώματα τύπου transfersome-TRs και τύπου invasomes-INVs) χαρακτηρίστηκαν ως προς τα εξής φυσικοχημικά χαρακτηριστικά: Την κατανομή μεγέθους, το ζ-δυναμικό, το σφαιρικό σχήμα και τη μορφολογία τους, την ικανότητα εγκλωβισμού υδρόφιλων ουσιών, τη σταθερότητά τους (ως προς τα μορφολογικά χαρακτηριστικά, τη διασπορά μεγέθους και το φορτίο επιφανείας, και τη συγκράτηση της εγκλωβισμένης σε αυτά ουσίας) σε σχέση με το χρόνο, την ελαστικότητα και τέλος ως προς τη δυνατότητα διαπέρασης εγκλωβισμένων σε αυτές υδρόφιλων ουσιών μέσω ανθρώπινου δέρματος in vitro. Το μέγεθος των λιποσωμάτων ήταν παρόμοιο και αρκετά ομοιογενές, ενώ η προσθήκη διαφορετικών τύπων ενισχυτικών διαπέρασης στα ελαστικά λιποσώματα, στα συνήθη εύρη συγκεντρώσεων που χρησιμοποιούνται, δεν επηρεάζει καθόλου το επιφανειακό φορτίο των παραχθέντων λιποσωμάτων. Αύξηση του μεγέθους και αστάθεια ως προς τη συγκράτηση της εγκλωβισμένης ουσίας παρατηρήθηκε στην περίπτωση προσθήκης μεγαλύτερης ποσότητας ενισχυτικού διαπέρασης, η οποία αλλάζει και τα φυσικοχημικά χαρακτηριστικά των λιποσωμάτων. Τα TRs που περιείχαν χολικό νάτριο ήταν πιο ελαστικά από τα αντίστοιχα με Tween 80, τα οποία είχαν συγκριτικά χαμηλές τιμές ελαστικότητας (<40mg/s∙cm2). Οι υψηλότερες τιμές ελαστικότητας από όλους τους τύπους ελαστικών λιποσωμάτων που παρασκευάστηκαν στα πλαίσια αυτής της διατριβής, παρατηρήθηκε στην περίπτωση των INVs με 1% w/w PE και 1% w/w LIM. Επιπλέον, τα περισσότερα λιποσώματα τύπου INVs είχαν υψηλότερες τιμές ελαστικότητας σε σχέση με τα αντίστοιχα χωρίς τερπένια (INVs αναφοράς), εκτός από την περίπτωση των INVs με citral και cineol, όπου η ελαστικότητα σημείωσε μείωση σε σχέση με τα INVs χωρίς τερπένια. Οι διάφοροι τύποι λιποσωμάτων φαίνεται να μεταβάλλουν τη διαπέραση της χρωστικής με την εξής σειρά: Διάλυμα<CLs<TRs<<INVs. H διαπερατότητα (permeability), η ροή (flux) και ο λόγος προσαύξησης (ER) δείχνουν ότι τα συμβατικά λιποσώματα αύξησαν ελάχιστα τη ροή της καλσεΐνης, ενώ τα TRs και INVs κατά 1.8 και 7.2 φορές, αντίστοιχα. Τα αποτελέσματα αυτά επιβεβαιώνουν το γεγονός ότι τα συμβατικά λιποσώματα είναι ανεπαρκή συστήματα μεταφοράς υδρόφιλων μορίων μέσω του δέρματος, ενώ παράλληλα δείχνουν ότι τα ελαστικά λιποσώματα με τη μεγαλύτερη τιμή ελαστικότητας είναι πιο αποτελεσματικά στη μεταφορά της ουσίας μέσω του δέρματος. Σε επόμενα πειράματα μελετήθηκε η δυνατότητα διείσδυσης τόσο υδρόφιλων όσο και λιπόφιλων μορίων στις στοιβάδες του δέρματος, σε μια προσπάθεια να διερευνηθεί ο μηχανισμός αύξησης της διαδερμικής διαπέρασης των υδρόφιλων χρωστικών από τους διάφορους τύπους ελαστικών λιποσωμάτων. Ως μοντέλο υδρόφιλης ουσίας χρησιμοποιήθηκε η φθορίζουσα χρωστική καλσεΐνη, ενώ η λιπιδική ροδαμίνη χρησιμοποιήθηκε ως μοντέλο λιπόφιλης ουσίας (που δεν φεύγει από τα λιποσώματα και ουσιαστικά μας δείχνει το βάθος εις το οποίο εισχωρούν μέσα στο δέρμα τα αντίστοιχα είδη λιποσωμάτων). Τα λιποσώματα τύπου TR φαίνεται ότι επάγουν τη διαπέραση με το να βοηθούν τη χρωστική να προχωρά (υπό μορφή λιποσωμάτων που την εγκλωβίζουν) σε βαθύτερα στρώματα της κεράτινης στιβάδας σε σχέση με τα συμβατικά λιποσώματα όπου σε μεγάλο ποσοστό διαρρηγνύονται και απελευθερώνουν την υδρόφιλη ουσία η οποία στη συνέχεια διέρχεται μόνη της, ως ελεύθερο μόριο, στις στιβάδες του χορίου. Αντίθετα, τα λιποσώματα τύπου INV αποδείχτηκε ότι εισδύουν σε βαθύτερες στιβάδες της επιδερμίδας, φθάνοντας σε αρκετά υψηλά ποσοστά σε στιβάδες του χορίου, παρασύροντας μαζί τους και τα μόρια του εγκλωβισμένου σε αυτά υδρόφιλου φαρμάκου. Τέλος, μελετήθηκε η δυνατότητα μορφοποίησης ενός πειραματικού φαρμάκου με ανάλογη δομή γνωστού φαρμάκου προκειμένου για διαδερμική αντιϋπερτασική θεραπεία. Αρχικά, μελετήσαμε το πειραματικό φάρμακο ως προς τις φυσικοχημικές του ιδιότητες (διαλυτότητα σε διάφορα μέσα, σύνδεση με πρωτεΐνες) και στη συνέχεια μελετήσαμε τη δυνατότητα χορήγησης μιας φαρμακοτεχνικής μορφής μέσω του δέρματος σε κατάλληλο σύστημα διαλυτών. Αφού βρέθηκαν οι κατάλληλες συνθήκες, χρησιμοποιήθηκαν ενισχυτικά διαπέρασης στη φαρμακοτεχνική μορφή για να επιταχυνθεί η διαδερμική απορρόφηση του φαρμάκου, όσο είναι δυνατόν, και να ευρεθεί η βέλτιστη φαρμακοτεχνική μορφή. Τέλος, πραγματοποιήθηκαν πειράματα σύγκρισης μεταξύ του πειραματικού φαρμάκου και γνωστού αντιϋπερτασικού (Los) ως προς τις φυσικοχημικές ιδιότητες και την ικανότητα μεταφοράς τους διαδερμικά. Τα αποτελέσματα έδειξαν ότι το ΠΦ παρουσίασε μεγαλύτερη διαπέραση υπό μορφή ουδέτερου μορίου (σε σχέση με την αντίστοιχη του άλατος με TFA (όπως φάνηκε από τα αρχικά πειράματα αυτής της σειράς) ή του μετά Καλίου άλατος (όπως προκύπτει μετά από σύγκριση των σχετικών τιμών Ροής και Συντελεστή Διαπερατότητας (P). Συγκρίνοντας λοιπόν τις τιμές διαπερατότητα και ροής διαμέσου ανθρώπινης επιδερμίδας με τις αντίστοιχες τιμές του φαρμάκου Los θα πρέπει να λάβουμε υπ’ όψη και τις τιμές για το ουδέτερο μόριο. Η διαπέραση του ουδέτερου μορίου του ΠΦ είναι σημαντικά χαμηλότερη από την αντίστοιχη του μετά καλίου άλατος της los. / In this study, we investigated the use of elastic liposomes in transdermal delivery of hydrophilic substances and we studied the possibility of formulating a new antihypertensive drug for transdermal delivery. Primarily, morphological studies of human skin were conducted by the use of optical microscopy and transepidermal water loss measurements (TEWL), in order to assess the barrier function of stratum corneum (SC), and the integrity of the techniques used in this study. By optical microscopy, in particular, data concerning the skin structure and the possible mechanism by which substances can be delivered through / into the skin, were obtained. Secondly, we studied and compared various physicochemical characteristics of two different types of elastic liposomes, which could help us predict the transdermal absorption (in vivo) of hydrophilic molecules. Fluorescent markers calcein and carboxyfluorescein were used as hydrophilic model drugs. All liposomal dispersions (conventional liposomes CLs, and elastic liposomes i.e. transfersomes TRs and invasomes INVs) were evaluated in means the following physicochemical properties: size distribution, z-potential, stability upon storage, morphology by cryo-electron microscopy and membrane elasticity. Moreover, their ability to encapsulate and also to retain aqueous soluble markers, was investigated. Finally, the permeation of calcein through human skin was tested and compared by use of elastic and conventional rigid liposomes. The mean diameter was found relatively homogenous, similar for most liposomal dispersions, while the addition of different penetration enhancers during the preparation did not influence z-potential. Increase of size average and instability – as far as the retention of the encapsulated substance is concerned – was observed at higher concentrations of penetration enhancers used. Sodium cholate containing TRs were found more elastic compared to Tween 80 containing TRs, which showed relatively low elasticity values (<40mg/s∙cm2). The highest elasticity values among all types of elastic liposomes prepared, were found in the case of INVs with 1%w/w PE and 1% w/w LIM. Furthermore, most INVs showed higher elasticity values compared to the ones without terpenes (control INVs), except from citral and cineol INVs, where elasticity decreased compared to the control ones. It appears that different types of liposomes can alter fluorescent permeation in the following order: Solution<CLs<TRs<<INVs. Permeability, flux and enhancement ratio (ER) show that conventional liposomes increased slightly calcein flux, while TRs and INVs 1.8 and 7.2 times respectively. These findings confirm the fact that CLs are inefficient drug delivery systems for water soluble molecules through human skin, and show that elastic liposomes having the highest elasticity value are more efficient in delivering CF transdermally. In further experiments, the penetration of both hydrophilic and lipophilic molecules in human skin was studied, in order to investigate the mechanism of action by which liposomes could enhance the drug delivery in skin. Fluorescent marker calcein was used as a hydrophilic drug model, while lipid rhodamine-PE was used as a lipophilic model (it shows us how deeply the liposomes penetrate into the skin). Liposomes TRs seem to enhance skin permeation by helping the marker to penetrate (through liposomes) in deeper stratum corneum layers while conventional liposomes the hydrophilic substance which penetrates the skin layers as a free molecule. In contrast, INV liposomes were proved to be able to penetrate in deeper skin layers, and deliver relatively high amounts of the encapsulated substance. In the end, experiments with a new molecule with similar structure to losartan were conducted. This study aimed at discovering a new formulation for this experimental drug in order to be used as a transdermal antihypertensive. First, we studied the physicochemical properties (solubility in PBS, BSA etc, and protein binding). Secondly, we investigated the possibility of preparing a formulation to be used transdermally. After establishing the techniques and drug properties we used penetration enhancers in order to increase the transdermal absorption as possible and help find the right skin formulation. Last, we compared the experimental drug and losartan in terms of physicochemical properties and their ability to be transported through human skin. The results showed that the experimental drug had better permeation rate as a neutral molecule compared to TFA salt, (as shown in preliminary experiments) or K+ (as shown after comparing P and flux values). Therefore, the values given for the neutral molecule should be taken into consideration when comparing the two drugs. (losartan and experimental drug). The permeation of the neutral molecule nevertheless is significantly lower than the one for losartan.

Made available in DSpace on 2016-08-17T18:39:35Z (GMT). No. of bitstreams: 1 3372.pdf: 2042678 bytes, checksum: 9beea5d2ce56b34888b3e4efc74386a4 (MD5) Previous issue date: 2010-09-24 / The gold standard for evaluating skin atrophy is the histological study. When compared to the technique of Fluorescence Spectroscopy (FS), histology requires the physical removal of tissue and their processing in the laboratory, while the FS conducts fast assessments in vivo. The objective of this study was to standardize a methodology for inducing skin atrophy in an experimental model, compare the collagen in normal and atrophic skin, and estimate the potential assessment of FS in skin atrophy. We used 20 adult male Wistar rats, from the UFSCar Central Animal Biotery, kept in a controlled environment. The cutaneous atrophy was induced with topical use of the glucocorticoid Clobetasol propionate 0.05%, 2 times daily for 14 days and evaluated by histological analysis and FS with laser excitation at 532nm and 408nm. We evaluated 96 skin fragments with HE and picrosirius red staining. In biopsies from the first day, the average of epidermal thickness was 44 ± 9&#956;m and, after 14 days of CB, was 16 ± 6&#956;m (p <0.0001), confirming atrophy. This result was confirmed by staining with picrosirius red, which was observed coarsed and disorganized rearrangement of the collagen fibers in the dermis after the use of corticosteroids. For the analysis of results from FS, the spectra have been nominated as "normal" or "atrophic" in correspondence to the histological study. The FS with 408nm laser analysis allowed to distinguish the "normal" and "atrophic" group with fewer spectral parameters. In the future, this technique could be used as a complementary diagnostic method in dermatology. / O padrão ouro para avaliar a atrofia de pele é o estudo histológico. Quando comparada à técnica de Espectroscopia de Fluorescência (EF), a histologia exige a remoção física de tecidos e seu processamento em laboratório; enquanto a EF realiza avaliações rápidas e in vivo. O objetivo dessa pesquisa foi padronizar uma metodologia para indução de atrofia cutânea em modelo experimental; comparar o colágeno na pele normal e atrófica; e estimar o potencial da EF na avaliação da atrofia cutânea. Foram utilizados 20 ratos machos Wistar adultos, provenientes do Biotério Central da UFSCar, mantidos em ambiente controlado. A atrofia cutânea foi induzida com o uso tópico do glicocorticóide propionato de clobetasol a 0,05% (CB), 2 vezes ao dia, por 14 dias, e avaliada por meio de estudo histológico e EF com laser de excitação em 532nm e 408nm. Foram avaliados 96 fragmentos de pele com coloração HE e Picrosirius red. Nas biópsias do primeiro dia, a média de espessura da epiderme foi de 44±9&#956;m e, após 14 dias de CB, foi de 16±6&#956;m (p<0,0001), confirmando a atrofia. Esse resultado foi corroborado pela coloração com Picrosirius red, na qual se observou, após uso de corticóide, rearranjo mais grosseiro e desorganizado das fibras colágenas da derme. Para a análise dos resultados da EF, os espectros foram nomeados como normal ou atrófico , em correspondência ao estudo histológico. A avaliação por EF com laser de 408nm permitiu distinguir os grupos normal e atrófico com menor número de parâmetros espectrais. No futuro, esta técnica poderá ser usada como método de diagnóstico complementar na área da dermatologia.

Made available in DSpace on 2015-05-14T13:00:08Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1948005 bytes, checksum: 96df7a3d564809417a83d020664df9fc (MD5) Previous issue date: 2014-11-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Herpes simplex labialis, one of the most prevalent viral infections worldwide, is a chronic, relapsing incurable disease, persist throughout the lifetime of the host, usually in a latent form. Facing the difficulty of finding an effective therapy to traditional medicine, we seek new possibilities in complementary medicine treatment for this condition. The study aimed to perform non-clinical and clinical phase I and II toxicological tests with topical antiviral celodenina, neoflavonide synthesized from the ethanol extract of the stem bark of Coutarea hexandra (Jacq) K. Shum, topically. Preclinical studies have evaluated the dermal primary skin irritation - acute effect (single dose) and acute eye irritation (single dose) and in both experiments albino rabbits Zealanders, healthy adults were used in number 12, being 6 males and 6 females (control and treated) at a dose of 0.5 g of the cream. The assessment of primary skin irritation demonstrated that the cream does not irritate the skin of rabbits tested in Drug Testing Laboratory of the Federal University of Paraíba, since none showed any degree of erythema and edema throughout the experiment. Regarding eye irritation simple, cream showed low irritant effect, as only 33.3% rabbits showed redness in conjunctiva during the first 24 hours after application of the test substance. Did not identify any changes in the iris and cornea, in any animal throughout the experiment. To investigate the clinical phase I toxicity in humans, the celodenina, 30 volunteers were selected, of both sexes, clinically healthy, aged between 18 and 65 years. Study participants were treated daily, the night shift, by dermal route, with the cream for a period of four weeks and evaluated before the start of the study and after its termination hematology (CBC), biochemical (glucose, urea, creatinine, total cholesterol, AST, ALT, alkaline phosphatase), in order to detect possible changes resulting from use of cream in them, as well as to compare the results before and after the study. No abnormal values for both hematological variables as for biochemical between times and groups were highlighted. During treatment with the cream, some adverse reactions were observed in participants: local dryness (7%), burning (13%), tingling (7%) and erythema (7%), but the number of affected subjects was small, and symptoms and signs reported occurred in the first week of the study, not requiring specific treatment, disappearing spontaneously. Clinical phase II trials were randomized, double-blind, comparing celodenina 4% with placebo in 33 patients with recurrent herpes labialis between 18 and 65 years, who used these substances three times daily for 15 days. Patients were also assessed before and after the study of hematological and biochemical tests, which showed no significant values between times. Few adverse effects were reported, burning (21%) and local dryness (5.3%), both mildly during the first 30 minutes after application in the first five days. Herpes recurrences were evaluated for 30, 60 and 90 days and the participants treated with celodenina 4% had lower percentage of same relative to placebo at all time. These results suggest a low toxicity of the product, satisfactorily efficient control of relapses and indicate that this formulation can be used in Phase III clinical trials, dose and route of administration tested in the treatment of recurrent herpes labialis. / O herpes simples labial, uma das infecções virais mais prevalentes no mundo, é doença crônica, recidivante e incurável, persistindo durante toda a vida do hospedeiro, geralmente sob a forma latente. Frente à dificuldade de se encontrar uma terapia eficaz com a medicina tradicional, busca-se na medicina complementar novas possibilidades de tratamento para esta patologia. O estudo objetivou realizar ensaios toxicológicos, não clínico e clínicos fase I e II, com o antiviral celodenina, neoflavonoide sintetizado, a partir do extrato etanólico das cascas do caule de Coutarea hexandra (Jacq) K. Shum, via tópica. Os estudos dermais não clínicos avaliaram a irritação primária da pele efeito agudo (dose simples) e a irritação ocular aguda (dose simples) e em ambos os experimentos foram utilizados coelhos albinos neozelandeses, sadios, adultos, em número de 12, sendo 6 machos e 6 fêmeas (controle e tratado) para uma dose de 0,5 g do referido creme. A avaliação da irritação primária da pele demonstrou que o creme não é irritante para a pele dos coelhos testados no Laboratório de Ensaios Toxicológicos da Universidade Federal da Paraíba, já que nenhum deles apresentou nenhum grau de eritema e edema durante todo o experimento. Em relação à irritação ocular simples, o creme demonstrou efeito de baixa irritabilidade, porque apenas 33,3% coelhos apresentaram rubor em conjuntiva nas primeiras 24 horas após a aplicação da substância em estudo. Não foi identificada nenhuma alteração na íris e na córnea, em qualquer dos animais em todo o experimento. Para investigar a toxicidade clínica fase I, em seres humanos, da celodenina, foram selecionados 30 voluntários, de ambos os sexos, clinicamente saudáveis, com faixa etária compreendida entre 18 e 65 anos. Os participantes do estudo foram tratados diariamente, no turno da noite, por via dermal, com o creme por um período de 4 semanas e avaliados antes do início do estudo e após o seu término com exames hematológicos (hemograma completo), bioquímicos (glicemia, uréia, creatinina, colesterol total, AST, ALT, fosfatase alcalina), com o objetivo de detectar possíveis alterações decorrentes da utilização do creme nos mesmos, bem como, comparar os resultados antes e após o término do estudo. Não foram evidenciados valores alterados, tanto para as variáveis hematológicas como para as bioquímicas entre os tempos e os grupos. Ao longo do tratamento com o creme, foram observadas algumas reações adversas nos participantes: ressecamento local (7%), ardor (13%), formigamento (7%) e eritema (7%), mas o número de voluntários acometidos foi pequeno, e os sintomas e sinais relatados ocorreram na primeira semana do estudo, não necessitando de tratamento específico, desaparecendo espontaneamente. Os estudos clínicos fase II foi randomizado, duplo-cego, comparando a celodenina 4% com placebo em 33 pacientes portadores de herpes labial recorrente entre 18 e 65 anos, que utilizaram as referidas substâncias 3 vezes ao dia durante 15 dias. Os pacientes também foram avaliados antes e após o término do estudo com exames hematológicos e bioquímicos, os quais não demonstraram valores significativos entre os tempos. Poucos efeitos adversos foram relatados, o ardor (21%) e o ressecamento local (5,3%), ambos, de forma branda, durante os primeiros 30 minutos após a aplicação nos primeiros 5 dias. As recidivas herpéticas foram avaliadas durante 30, 60 e 90 dias e os participantes tratados com celodenina 4% apresentaram menor percentual das mesmas em relação ao placebo em todos os tempos. Estes resultados sugerem a baixa toxicidade do produto, eficiência satisfatória no controle das recidivas e indicam que esta formulação pode ser utilizada para testes clínicos fase III, na dose e via de administração testada no tratamento do herpes labial recorrente.

Made available in DSpace on 2015-05-14T13:00:16Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1932289 bytes, checksum: a18b6ccc194715163ed381d04f52ec3d (MD5) Previous issue date: 2011-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The study aimed to perform toxicological tests and preclinical dermal clinical phase I, the hydrogel obtained from the hydroalcoholic extract from the bark of Anacardium occidentale Linn. The dermal preclinical studies have assessed the primary irritation of the skin - acute (single dose) and acute eye irritation (single dose) and in both experiments were used rabbits albino, New Zealand, healthy adults, numbering 12, with 6 males and 6 females (control and treated) for a dose of 0.5 g of the hydrogel obtained from the alcoholic extract of Anacardium occidentale Linn. The evaluation of primary irritation of the skin demonstrated that the hydrogel from the stem bark of Anacardium occidentale Linn is not irritating to the skin of rabbits tested in our laboratory, since only 25% of the rabbits showed barely perceptible erythema in the initial phase of the experiment (first time), and no degree of swelling was observed in rabbits throughout the experiment. In relation to the simple eye irritation, the hydrogel from the stem bark of Anacardium occidentale Linn also did not showed irritant effect, because only 33,3% and 8,3% rabbits showed, respectively, conjunctival redness and swelling in the first 24 hours after application of test substance. Did not present any change in level of the iris and cornea, in any animal throughout the experiment. To investigate the clinical phase I toxicity in humans, hydrogel from the stem bark of Anacardium occidentale Linn, we selected 28 volunteers, clinically healthy, aged between 18 and 25. Study participants were divided into two groups, male and female, with 14 participants each, and treated daily, on the night shift, via dermal, with the hydrogel from the stem bark of Anacardium occidentale Linn by a period of 4 weeks. The volunteers were tested before the start of the study and eight weeks after the study, haematological (CBC) and biochemical (glucose, urea, creatinine, total cholesterol, AST, ALT, alkaline phosphatase), in order to detect possible changes arising from the use of hydrogel in patients, as well as compare the results before and after the study. There was no evidence values changed for both hematology and for biochemical variables between times and groups. During treatment with the hydrogel from the stem bark of Anacardium occidentale Linn, Some adverse reactions were observed in participants: tingling, redness, and stinging, but the number of volunteers affected was small, and the reported symptoms occurred during the first weeks of the study and did not require specific treatment and disappeared spontaneously. Only 3,5% of the female volunteers reported feeling oily skin in three weeks of the study. In contrast, 10,7% (first week) and 3,5% (second week) of male volunteers reported skin feeling soft, "cleaner". These results suggest and the low toxicity of the product and indicate that this herbal formulation can be used by the population, the dose and route of administration tested. / O estudo objetivou realizar ensaios toxicológicos pré-clínicos dermais e clínicos fase I, com o hidrogel obtido a partir do extrato alcoólico das cascas de Anacardium occidentale Linn. Os estudos dermais pré-clínicos avaliaram a irritação primária da pele efeito agudo (dose simples) e a irritação ocular aguda (dose simples) e em ambos os experimentos foram utilizados coelhos albinos neozelandeses, sadios, adultos, em número de 12, sendo 6 machos e 6 fêmeas (controle e tratado) para uma dose de 0,5 g do hidrogel obtido a partir do extrato alcoólico das cascas de Anacardium occidentale Linn. A avaliação da irritação primária da pele demonstrou que o hidrogel das cascas do caule de Anacardium occidentale Linn não é irritante para a pele dos coelhos testados em nosso laboratório, já que apenas 25% dos coelhos estudados apresentaram eritema apenas perceptível, na fase inicial do experimento (primeira hora), e nenhum grau de edema foi observado nos coelhos durante todo o experimento. Em relação à irritação ocular simples, o hidrogel das cascas do caule de Anacardium occidentale Linn demonstrou também efeito não irritativo, porque apenas 33,3% e 8,3% dos coelhos, respectivamente, apresentaram rubor e edema em conjuntiva nas primeiras 24 horas após a aplicação da substância em estudo. Não foi identificada nenhuma alteração na íris e na córnea, em qualquer dos animais em todo o experimento. Para investigar a toxicidade clínica fase I, em seres humanos, do hidrogel das cascas do caule de Anacardium occidentale Linn, foram selecionados 28 voluntários, clinicamente saudáveis, com faixa etária compreendida entre 18 e 25 anos. Os participantes do estudo foram distribuídos em dois grupos, masculino e feminino, com 14 participantes cada um, e tratados diariamente, no turno da noite, por via dermal, com o hidrogel das cascas do caule de Anacardium occidentale Linn por um período de 4 semanas. Os voluntários foram avaliados antes do início do estudo e 8 semanas após o seu término com exames hematológicos (hemograma completo), bioquímicos (glicemia, uréia, creatinina, colesterol total, AST, ALT, fosfatase alcalina), com o objetivo de detectar possíveis alterações decorrentes da utilização do hidrogel nos pacientes, bem como, comparar os resultados antes e após o término do estudo. Não foram evidenciados valores alterados, tanto para as variáveis hematológicas como para as bioquímicas entre os tempos e os grupos. Ao longo do tratamento com o hidrogel das cascas do caule de Anacardium occidentale Linn, foram observadas algumas reações adversas nos participantes: formigamento, hiperemia, e ardência, mas o número de voluntários acometidos foi pequeno, e os sintomas relatados ocorreram nas primeiras semanas do estudo, não necessitando de tratamento específico, desaparecendo espontaneamente. Apenas 3,5% dos voluntários do sexo feminino relatou sensação de pele oleosa nas 3 últimas semanas do estudo. Em contrapartida, 10,7% (primeira semana) e 3,5% (segunda semana) dos voluntários do sexo masculino referiram sensação de pele macia, mais limpa . Estes resultados sugerem a baixa toxicidade do produto e indicam que esta formulação fitoterápica pode ser utilizada pela população, na dose e via de administração testada.

Objetivo: O objetivo deste estudo clínico, controlado, randomizado, foi comparar duas técnicas cirúrgicas para recobrimento radicular com enxerto de matriz dérmica acelular (EMDA) para avaliar qual procedimento proporcionaria maior recobrimento radicular e quantidade de tecido queratinizado. Materiais e Métodos: Foram selecionados 15 pacientes com retrações gengivais bilaterais Classe I ou II de Miller. Os 15 pares de retrações foram designados e tratados aleatoriamente no grupo teste, e as retrações contralaterais no grupo controle. O EMDA foi utilizado em ambos os grupos. No grupo controle o enxerto e o retalho foram posicionados no nível da junção amelocementária (JAC), e no grupo teste o enxerto foi estabilizado 1 mm apical a JAC e o retalho 1 mm coronal a JAC. Os parâmetros clínicos avaliados foram profundidade de sondagem (PS), nível clínico de inserção relativo (NCIR), altura da retração gengival (RG), e a altura (GQ) e espessura da gengiva queratinizada (EGQ). A área da retração gengival (ARG), um novo parâmetro, foi medida em fotografias padronizadas através da utilização de um aparelho apropriado e um programa de computador. As medidas foram tomadas antes das cirurgias e após 6 meses das mesmas. Resultados: No exame inicial todos os parâmetros foram similares para ambos grupos. Houve diferença estatisticamente significante favorecendo a técnica proposta para todos os parâmetros com exceção da quantidade de tecido queratinizado após 6 meses. Conclusão: A técnica teste proposta se mostrou mais adequada para procedimentos de recobrimento radicular com EMDA, e o novo parâmetro avaliado parece ser apropriado para análises de recobrimento radicular. (Protocolo de registro Clinicaltrials.gov: NCT01175720) / Aim: The aim of this randomized, controlled, clinical study was to compare two surgical techniques for root coverage with the acellular dermal matrix graft (ADMG) to evaluate which procedure could provide better root coverage and greater amounts of keratinized tissue. Materials and Methods: Fifteen patients with bilateral Miller Class I or II gingival recessions were selected. Fifteen pairs of recessions were treated and assigned randomly to the test group, and the contralateral recessions were assigned to the control group. The ADMG was used in both groups. In the control group the graft and flap were positioned at the level of the cemento-enamel junction (CEJ), and in the test group the graft was positioned 1mm apical to the CEJ and the flap 1mm coronal to the CEJ. The clinical parameters evaluated were probing depth (PD), relative clinical attachment level (RCAL), gingival recession height (GR) and the width (KT) and thickness of keratinized tissue (TKT).The gingival recession area (GRA), a new parameter, was measured in standardized photographs through a special device and software. The measurements were taken before the surgeries and after 6 months. Results: At baseline, all parameters were similar for both groups. There were statistically significant differences favouring the proposed technique for all parameters except for the amount of keratinized tissue at 6 months. Conclusions: The proposed test technique is more suitable for root coverage procedures with ADMG, and the new parameter evaluated appears valuable for root coverage analysis.(Clinicaltrials.gov Identifier: NCT01175720).

Ainda que resulte na sobrevida do paciente, o tratamento atual de queimaduras profundas e extensas é imperfeito. A contratura cicatricial e o aspecto rendilhado persistentes na área enxertada produzem resultados estéticos e funcionais pobres. A principal dificuldade no adequado restabelecimento do tegumento destes pacientes é o déficit de derme, decorrente da reposição das perdas com enxertos relativamente finos. Neste trabalho são relatados quatro casos, decorrentes da familiaridade obtida em nossa prática clínica com o emprego de pele preservada em glicerol, nos quais foi utilizada a enxertia combinada, isto é, derme alógena residual sobreposta por enxertos de espessura parcial autógenos, como forma de reposição de matriz dérmica. Os tegumentos resultantes da enxertia combinada mostraram-se estáveis e duráveis, dentro do período de seguimento dos casos apresentados. / Although it results in the patient\'s survival, the current treatment of deep and extensive burns is imperfect. Scar contracture and the persistent lacy aspect in the grafted area produce aesthetic and functional poor results. The main difficulty in the appropriate re-establishment of the tegument of these patients is the deficit of dermis, due to the replacement of the skin losses with relatively thin grafts. In this work, decurrent of the familiarity obtained in our clinical practice with glycerol preserved cadaver skin, four cases are reported, which the combined grafting was used, that is, residual allogeneous dermis put upon by split thickness autogenous grafts, as form of replacement of dermal matrix. The resulting teguments of the combined grafting were shown stable and durable, inside the follow-up period of the presented cases.

L’objectif de ce projet est d’étudier l’interaction de nanoparticules polymères avec les membranes, soit directement sur des cellules entières ou grâce à des modèles membranaires biomimétiques, dans l’optique de valider leur utilisation dans le cadre d’applications biologiques. Des nanoparticules (NPs) polymères cœur/enveloppe avec un diamètre inférieur à 100 nm ont été synthétisés. Cette taille a été choisie afin de leur permettre de pénétrer à travers les membranes plasmiques. Des nanoparticules ayant la même composition chimique mais avec un diamètre hydrodynamique supérieur, de l’ordre de 250 nm, ont été également préparées afin de mettre en évidence l’effet de la taille des particules sur le processus d’internalisation cellulaire. Dans cette thèse, une méthode innovante de synthèse monotope a été développée pour obtenir des NPs coeur-enveloppe, compatibles en milieu aqueux et présentant à leur surface des résidus iniferter. Le coeur est composé de polystyrène avec une taille d’environ 30 nm. Un large éventail de fonctionnalités peut être greffé sur la surface du coeur par polymérisation radicalaire contrôlée en faisant varier différents types de monomères. L’épaisseur de l’enveloppe peut être ajustée en fonction de la concentration en monomère et du temps de polymérisation. Les nanoparticules synthétisées ont été caractérisées par diffusion dynamique de la lumière, par spectroscopie infrarouge à transformée de Fourier, par analyse micro-élémentaire et par microcopie à transmission électronique. Les interactions des NPs à coeur polystyrène et avec des enveloppes de charge neutre et négative ont été étudiées avec des cellules kératinocytes épidermiques humaines néonatales (NHEK), des fibroblastes primaires humains et les cellules HACaT de kératinocytes humains. Les études de cytotoxicité réalisées en utilisant un marquage à l’iodure de propidium et un test à la lactate déshydrogénase n’ont relevé aucune toxicité sur les lignées testées. Cependant, le suivi de la prolifération cellulaire par impédance électrique de substrats cellulaires a indiqué que les nanoparticules anioniques induisent une forte diminution de la prolifération des kératinocytes. L’internalisation cellulaire des NPs a été confirmée par microscopie confocale qui n’indique pas leur colocalisation avec les endosomes précoces, les lysosomes et l’actine. De plus, les données obtenues par triage cellulaire par cytofluorométrie soutiennent qu’un mécanisme énergétiquement-dépendant est mis en œuvre pour l’internalisation des NP neutres, ce qui semble être moins le cas pour les nanoparticules négatives. Les membranes biomimétiques ont été employées afin d’étudier les spécificités des interactions entre nanoparticules et lipides dans des conditions contrôlées. L’étude sur des modèles de vésicules géantes couplée à de la spectroscopie de fluorescence a révélé que les nanoparticules coeur/enveloppe sont capables d’interagir profondément dans la région hydrophobe de la membrane, mais uniquement quand la bicouche lipide est en phase fluide désordonnée. Le mode de pénétration des NPs au travers de la bicouche des vésicules semblent engendrer la formation de pores. Un effet plus prononcé de rigidification de la bicouche a pu être observé lors de l’interaction de nanoparticules chargées négativement avec les bicouches de phosphatidycholines. Cet effet pourrait être attribué à un changement de l’orientation des têtes phosphocholines du à des interactions électrostatiques. En conclusion, les nanoparticules polymère que nous avons synthétisées apparaissent être des outils polyvalents pour les études d’interaction cellulaire et d’imagerie. Ces nanomatériaux peuvent être éventuellement être employés pour la délivrance de médicaments en incorporant les molécules actives dans une enveloppe polymère thermosensible par exemple. / This project’s aim was to study polymeric nanoparticle-membrane interactions using both live cells and biomimetic models with the idea to validate such nanoparticles for use in bio-applications. Core-shell polymeric nanoparticles below 100 nm, as this small size is capable of penetrating plasma membranes, were synthesised. Nanoparticles (NPs) with the same chemical composition but with hydrodynamic diameters of ~250 nm, were also prepared in an effort to highlight any effect of NP size on cell internalisation. In this thesis, an innovative method is presented for the synthesis of water-compatible, iniferter-bound polystyrene core shell NPs (~30 nm) using a one-pot synthetic method. A plethora of functionalities could be added to the nanoparticles via shell grafting from the surface of the polystyrene core in the presence of additional monomers via controlled living radical polymerisation. Shell thickness could be tuned as a function of monomer’s concentration and polymerisation time. The nanoparticles were fully characterised by dynamic light scattering, Fourier transform infra-red spectroscopy, microelemental analysis and transmission electron microscopy. Further, the interactions of polystyrene core NPs possessing neutral and anionic shells were investigated using neonatal human epidermal keratinocytes (NHEK), human primary fibroblasts and HaCaT cells. Cytotoxicity studies performed using propidium iodide and lactate dehydrogenase indicated no evidence of cytotoxicity in either cell line. However, cell proliferation monitored by electric cell substrate impedance sensing (ECIS) protocols indicated that anionic nanoparticles induced a dramatic decrease in cell proliferation in keratinocytes. The cellular internalisation of NPs was confirmed by confocal microscopy and no co-localisation was found with early endosomes, lysosomes or actin. Additionally, fluorescence activated cell sorting (FACS) data support the theory that an energy-dependent mechanism is employed for neutral NP internalisation but less so for negatively charged NPs. Biomimetic membrane models were used to investigate specific nanoparticle-lipid interactions under controlled conditions. Employing giant vesicles coupled with fluorescent spectroscopy techniques revealed that core-shell nanoparticles interact deep in the hydrophobic region of bilayers only when the membrane is in the fluid phase. Their mode of entering artificial cells (i.e giant vesicles) appears to cause the formation of pores. Anionic nanoparticles interact with the choline moiety of phosphatidylcholine and confer a rigidifying effect on phosphocholine containing bilayers. Therefore we conclude that the polymeric nanoparticles that we synthesized are versatile tools for cell interaction and imaging studies. These nanomaterials could eventually be applied to drug delivery studies by incorporation of the drug in for instance a thermoresponsive polymeric shell. Furthermore, it is clear that NPs coated with anionic and neutral polymeric shells present a lower toxicity profile than previously reported cationic nanoparticles. Both nanoparticles increase the order lipid bilayer vesicles composed of POPC (the most common glycerophospholipid) in animal and plants. Anionic nanoparticles in particular exhibit a rigidifying effect on POPC lipid bilayers and their mode of entry into cells may be due to the formation of pores which was determined to not induce cell death.

L'élastine est la protéine matricielle responsable de l'élasticité des tissus retrouvée dans des tissus soumis à de fortes contraintes mécaniques tels que les poumons, les artères ou la peau. La dégradation de cette protéine lors de processus physiopathologiques produit des peptides bologiquement actifs nommés peptides d'élastine portant le motif GXXPG essentiel à leur activité. Ces peptides régulent diverses fonctions biologiques telles que le chimiotactisme, la synthèse de protéases, la prolifération. Tous ces effets dépendent de la fixation des peptides d'élastine au complexe récepteur de l'élastine. Ce complexe est composé de trois sous-unités : une protéine périphérique de 67 kDa, l'Elastin Binding Protein (EBP), et deux protéines associées à la membrane, la Protective Protein/Cathepsin A (PP/CA) et la Neuraminidase-1 (Neu-1) de 55 et 61 kDa respectivement. L'activité sialidase de Neu-1 est responsable de l'activation de ERK 1/2 après fixation des peptides d'élastine au complexe récepteur de l'élastine.Dans cette étude, nous démontrons que l'EBP et les radeaux lipidiques sont colocalisés à la membrane plasmique. Nous montrons, de plus, que la déstructuration de ces microdomaines aussi bien que leur déplétion en glycolipides bloque la signalisation du récepteur. L'utilisation d'un anticorps monoclonal bloquant dirigé contre le GM3 montre qu'il est essentiel à la signalisation. Après traitement par les peptides d'élastine, le contenu cellulaire en GM3 diminue alors que celui en lactosylcéramide augmente suggérant une conversion du GM3 en lactosylcéramide. L'utilisation de lactose ou de siRNA Neu-1 bloque cette conversion ce qui tend à démontrer que le complexe récepteur de l'élastine est impliqué dans ce mécanisme. Une analyse par cytométrie en flux confirme cette production de lactosylcéramide induite par les peptides d'élastine.L'analyse par spectrométrie de masse mettrait en évidence deux lactosylcéramides (C23:0 et C24:1) potentiellement bioactifs dont la synthèse chimique a été entreprise. La purification des radeaux lipidiques par ultracentrifugation différentielle en gradient de saccharose ainsi que leur identification par Dot-blot couplé à la fluorescence montre un changement de densité de ces microdomaines après stimulation par les peptides d'élastine.L'évaluation biologique in vitro de ces lactosylcéramides montre qu'ils miment les effets des peptides d'élastine sur l'activation de ERK 1/2, la prolifération et la synthèse de MMP-1. Enfin, l'évaluation ex vivo des lactosylcéramides démontre une réduction de la zone de tissu cardiaque nécrosé suggérant un rôle cardioprotecteur de ces molécules. Ce travail propose un mécanisme original de transduction du signal à la membrane plasmique et nous laisse envisager le complexe récepteur de l'élastine, les peptides d'élastine et le lactosylcéramide comme de nouveaux agents thérapeutiques potentiels. / Elastin is the matrix protein responsible for the elasticity of tissues where resilience is required such as lung, arteries or skin. Elastin degradation during physiopathological processes produces biologically active peptides named elastin peptides bearing the GXXPG pattern essential for their activity. These peptides regulate various biological functions such as chemotaxis, proteases synthesis and proliferation. These effects are dependent of elastin peptide binding to the elastin receptor complex (ERC). This complex is composed of three subunits: a peripheral protein of 67 kDa called elastin binding protein (EBP) and two membrane-associated proteins, protective protein/cathepsin A (PP/CA) and neuraminidase-1 (Neu-1) of 55 and 61 kDa, respectively. The sialidase activity of Neu-1 is responsible for ERK 1/2 pathway activation following binding of elastin peptide on the elastin receptor complex.In this study, we demonstrate that EBP and lipid rafts colocalize at the plasma membrane. We also show that the disruption of these microdomains and their depletion in glycolipids block the receptor signaling. The use of a monoclonal anti-GM3 blocking antibody shows that this glycosphingolipid is essential for signaling. Following elastin peptide treatment, cellular GM3 level decreases while the lactosylceramide one increases consistently with a GM3/LacCer conversion. The use of lactose or Neu-1 siRNA blocks this process suggesting that the elastin receptor complex is involved in this mechanism. Flow cytometry analysis confirms this elastin peptide-driven LacCer generation.Mass spectrometry analysis of elastin peptide-stimulated cell membrane extracts identified two potentially bioactive lactosylceramides (C23:0 and C24:1) and their synthesis has been realized. Lipid rafts purification by differencial ultracentrifugation in sucrose gradient shows a variation of the microdomains density as well as their identification by fluorescence linked-Dot-blot following elastin peptide stimulation.In vitro biological evaluation of these lactosylceramides shows that they mimic the elastin peptide effects on ERK 1/2 activation, proliferation and MMP-1 synthesis. Finally, ex vivo lactosylceramides evaluation demonstrates a decrease of cardiac tissue necrosis area suggesting that these molecules could be cardioprotective agents. This work proposes an original mechanism of signal transduction at the plasma membrane and let us foresees the elastin receptor complex, elastin peptides and lactosylceramide as new potential therapeutical targets.

Avaliar a biocompatibilidade do fio lifting biológico - fio serrilhado de poliuretana de óleo de mamona - e sua eficácia no rejuvenescimento facial. Na primeira etapa deste trabalho implantamos os fios no dorso de camundongos, que foram sacrificados com 03, 07, 15 e 30 dias com posterior análise histológica por microscopia óptica. Na segunda fase implantamos os fios na face de pacientes com flacidez dérmica e analisamos, fotograficamente e através de uma modelagem numérico-computacional o resultado (rejuvenescimento), com intervalos entre 07 e 60 dias. As análises histológicas demonstraram uma rápida integração do fio ao tecido celular subcutâneo com formação abundante de colágeno e as fotografias dos pacientes revelaram uma maior firmeza da derme e um rejuvenescimento facial, comprovados pela análise computacional. Suas características químicas e físicas e os resultados iniciais nos permitem acreditar que o fio lifting biológico - fio serrilhado de poliuretana do óleo de mamona - apresenta elevada biocompatibilidade com uma rápida integração ao tecido subcutâneo sendo uma excelente opção no rejuvenescimento facial. / Evaluate the biological lifting thread - castor oil polyurethane serrulate thread - bio-compatibility and it´s eficacy on facial rejuvenation. At first we implanted the threads in subcutaneous tissues on mice backs that were sacrificed after 03, 07, 15 and 30 days, followed by histological analysis of material by using optical microscopy. Later, implants were carried out in patients with facial dermal flaccidity, and comparisons were made through photographs between 7 and 60 days, than we made a numerical-computational modelling comparision of this photographs. Histological analysis showed a quick thread integration with the celular subcutaneous tissue by a large amount of colagen syntesis and the patients photographs showed facial rejuvenation with improvement of the skin flaccidity comproved by numerical modelling. It`s chemical and physical characteristics and the initial results allow us belive that the biological lifting thread - castor oil polyurethane serrulate thread - has good bio-compatibility and fast integration with the celular subcutaneous tissue being an excellent option for the facial rejuvenation.