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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Efeitos da laserterapia de baixa potência, anti-inflamatório não-esteroidal tópico e atividade física no tratamento de osteoartrite induzida por papaína. / Effects of low-level laser therapy, topical non-steroidal antiinflammatory drug and physical activity on papain-induced osteoarthiritis.

Tomazoni, Shaiane da Silva 30 June 2015 (has links)
Introdução: A osteoartrite (OA) é uma doença que comumente afeta os seres humanos, sendo caracterizada como um processo degenerativo que abrange as articulações. A OA afeta a cartilagem articular, osso subcondral, ligamentos, cápsula articular, membrana sinovial e músculos periarticulares. O tratamento para esta desordem se baseia em terapia farmacológica, não farmacológica e cirúrgica, isoladamente ou em combinação, a fim de maximizar os efeitos benéficos e minimizar os efeitos indesejáveis. O presente estudo tem como objetivo avaliar e comparar os efeitos isolados e combinados da terapia farmacológica com anti-inflamatório não-esteroidal (AINE) de uso tópico, aos efeitos da atividade física, e por fim, aos efeitos da laserterapia de baixa potência (LBP), em um modelo experimental de OA. Materiais e Métodos: A OA foi induzida por injeção de papaína intra-articular no joelho direito de ratos Wistar machos. Após 21 dias os animais começaram a ser tratados com AINE de aplicação tópica e/ou com atividade física (natação) e/ou LBP. Os tratamentos foram realizados 03 vezes por semana, durante 08 semanas, perfazendo um total de 24 sessões de terapia. Foram realizadas análises bioquímicas e morfológicas da articulação do joelho, compreendendo análise histológica, contagem total de células, atividade de mieloperoxidase (MPO), RT-PCR (COX-1, COX-2, IL-1β, IL-6, IL-10, TNF-α, MMP-3 e MMP-13), análise de citocinas pelo método de ELISA (TNF-α, IL-1β, IL-6 e IL-10), PGE2 e por fim, a análise de Western-Blot (COX-1 e COX-2). Resultados, discussão e conclusão: Os resultados do presente estudo indicam que o tratamento com laserterapia de baixa potência é o mais eficiente em diminuir os danos à articulação e modular o processo inflamatório induzido pela injeção de papaína na articulação do joelho de ratos. / Introduction: Osteoarthritis (OA) is a disease that commonly affects humans and it is characterized as a degenerative process that reachs joints. OA affects the articular cartilage, subchondral bone, ligaments, joint capsule, synovial membrane and periarticular muscles. The treatment for this disorder is based on pharmacological therapy, non-pharmacological therapy and surgery, alone or in combination, in order to maximize the beneficial effects and minimize side effects. This research project aims to evaluate and compare the isolated and combined effects of pharmacological therapy with non-steroidal anti-inflammatory drug (NSAID) of topical use, to effects of physical activity and finally to effects of low-level laser therapy (LLLT) in an experimental model of osteoarthritis. Materials and Methods: OA was induced by intra-articular injection of papain in the right knee of male Wistar rats. After 21 days animals started to be treated with topical NSAID and/or physical activity (swimming) and/or LBP. Treatments was performed 3 times per week for 8 weeks, a total of 24 therapy sessions. It was performed morphological and biochemical analysis of the knee joint, including histology, counting of total cells, activity of myeloperoxidase (MPO), RT-PCR (COX-1, COX-2, IL-1β, IL-6, IL-10, TNF-α, MMP-3 and MMP-13) cytokines analysis by ELISA (TNF-α, IL-1β, IL-6 and IL-10), PGE2, and finally Western- Blot analysis (COX-1 and COX-2). Results, discussion and conclusion: The results of this project indicate that treatment with low-level laser therapy is more efficient in order to decrease damage in joint and to modulate inflammatory process induced by papain injection in rats knee join.
92

Avaliação da utilização do diclofenaco sódico isolado ou associado ao carisoprodol, paracetamol e cafeína, como adjuvante no tratamento de disfunções temporomandibulares crônicas / Assessment of administration of isolated sodium diclofenac or associated to carisoprodol, acetaminophen, and caffeine, as an adjuvant in management of chronic temporomandibular disorders

Fernando Kurita Varoli 04 August 2008 (has links)
A palavra DOR é definida como uma percepção consciente do indivíduo de impulsos nociceptivos modulados que originam uma experiência emocional e sensitiva desagradável, associada à lesão tecidual real ou potencial, ou descrita em termos de tal lesão. Considerando-se que a dor é um dos motivos mais comuns que levam um paciente a procurar por atendimento em consultório odontológico, este estudo teve como objetivo quantificar e qualificar a analgesia da musculatura mastigatória e da articulação temporomandibular proporcionada por medicamentos antiinflamatórios não esteroidais, associados ou não a outros agentes terapêuticos. O estudo clínico foi desenvolvido em pacientes que sofriam de algias crônicas na musculatura mastigatória, decorrentes de disfunções temporomandibulares. Foram selecionados, após anamnese e avaliação com a ferramenta RDC/TMD traduzido para a língua Portuguesa (PEREIRA JUNIOR, 2007), 18 voluntários para avaliar o efeito terapêutico (entendendo-se como efeito terapêutico o alívio da sintomatologia dolorosa e do restabelecimento da amplitude dos movimentos bordejantes mandibulares), dos três tratamentos coadjuvantes abaixo-relacionados, sendo dois medicamentos e um placebo para eliminar o efeito psicológico. Os tratamentos avaliados foram: um antiinflamatório não-esteroidal (AINES) Flanaren® (diclofenaco sódico), uma panacéia Sedilax® composta por AINES, miorrelaxante e analgésicos (diclofenaco sódico + carisoprodol + paracetamol + cafeína), ambos produzidos pelo laboratório Teuto® ; e um placebo, que consistia de pílulas preenchidas com 110 g de amido de milho, produzidas pela Faculdade de Ciências Farmacêuticas de Ribeirão Preto - USP. A administração de cada medicamento consistia de 1 unidade a cada 12 horas, durante um período de 10 dias, precedido e sucedido por avaliações de dor dos pacientes. Foi estabelecido um período de washout de 11 dias entre cada troca de tratamento. A avaliação dos tratamentos medicamentosos foi desenvolvida com diferentes ferramentas, como o McGill Pain Questionnaire (VAROLI; PEDRAZZI, 2006), para qualificar e quantificar dor não provocada, a escala visual analógica para dor à palpação, escala numérica para a quantificação da dor durante o tratamento, além de mensurações de amplitude de movimentos excursivos mandibulares. Foram colhidas também informações sobre possíveis efeitos colaterais indesejáveis relacionados aos tratamentos. O projeto foi submetido e aprovado pelo Comitê de Ética em Pesquisa envolvendo Seres Humanos da Faculdade de Odontologia de Ribeirão Preto da USP, Processo n.2006.1.558.58.0, Caae n.0022.0.138.000-06. Os resultados mostraram que a analgesia para a dor em repouso foi melhor com a utilização do Flanaren® e para a dor à palpação, igual para ambos os tratamentos. Os medicamentos Sedilax® e Flanaren® reduziram significantemente a dor após três dias de tratamento, enquanto o placebo, após oito dias. Não foram observadas melhoras na amplitude dos movimentos limítrofes da mandíbula. Também não foram observados efeitos colaterais significantes estatisticamente. Concluiu-se que o tratamento utilizando o diclofenaco sódico como adjuvante reduziu a dor em repouso; todos os tratamentos promoveram analgesia à dor à palpação, mas tanto o diclofenaco isolado como associado agiram no terceiro dia e o placebo, apenas no oitavo. Nenhum efeito colateral observado foi estatisticamente significante. / The word PAIN is defined as a conscious perception of modulated nociceptive input from an unpleasant emotional and sensitive experience, associated to a real or potential, or described in terms of such lesion. Considering that pain is one of main reasons which motivate patients to search for dental treatment, the aim of this study was quantify and qualify analgesia in masticatory muscles and temporomandibular joints by administration of non steroidal anti-inflammatory drugs, isolated or associated to other therapeutic agents. This clinical trial has been developed treating patients who had been suffering with chronic pain in masticatory muscles due to temporomandibular disorders. Eighteen volunteers were selected after anamnesis exam and assessment using RDC/TMD translated to Portuguese (PEREIRA JUNIOR, 2007), to evaluate the therapeutics effect (pain relief and maximum eccentric jaw movement recovery) of three adjuvant treatment: two medicines and one placebo, to eliminate psychological effects. Assessed treatments were: a non steroidal anti-inflammatory Flanaren® (sodium diclofenac), a panacea composed by an anti-inflammatory, muscle relaxant and analgesics (sodium diclofenac + carisoprodol + acetaminophen + caffeine), both produced by pharmaceutical laboratory Teuto® ; and a placebo, that were pills filled by 110 g of corn starch, produced by Faculty of Pharmaceutical Sciences of Ribeirão Preto USP. The dosage of all medicines was one pill every 12 hours, during 10 days, preceded and succeeded by patients` pain assessment. An 11 days washout period among each therapy has been established. The assessment of drug therapies were done using distinct instruments, as McGill Pain Questionnaire (VAROLI; PEDRAZZI, 2006), to qualify and quantify unprovoked pain; visual analogue scale for pain on palpation, numerical scale to quantify pain during treatment, and measurement of range of motion during maximum eccentric jaw movements. It has been obtained information about side effects related to treatments. The research project was submitted and approved by Ethics in Research Committee of Faculty of Dentistry of Ribeirão Preto USP, Lawsuit n.2006.1.558.0, CAAE n. 0022.0.138.000-06. Data analysis has shown that relief of unprovoked pain was better using Flanaren® , and reduction of pain on palpation was equal in all treatments. Both, diclofenac alone, also diclofenac associate to other drugs, reduced significantly pain after three days of treatment, while placebo, after eight days. It has not been observed increase of range of motion during maximum jaw excursive movements, neither statistically significant side-effect. It has been concluded that treatment using diclofenac as an adjuvant reduced unprovoked pain; all therapies relief pain on palpation, but it was observed on third day for diclofenac and diclofenac associated and on eighth day for placebo. There was not any statistically significant side effect.
93

Meloxicam e prednisona: efeito do tratamento oral de curto prazo nos n?veis de press?o intra-ocular de c?es (Canis familiaris) / Meloxican and prednisone: the effect of orally short term treatment on the intra-ocular pressure levels of dogs (Canis familiaris)

Souza, Maria Alice Fusco de 25 August 2006 (has links)
Made available in DSpace on 2016-04-28T20:18:32Z (GMT). No. of bitstreams: 1 2006-Maria Alice Fusco de Souza.pdf: 1870301 bytes, checksum: a5cdc0a6b5d34e7bd2f9f4705c4edc2d (MD5) Previous issue date: 2006-08-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / It is recognized the role of prostaglandins in lowering de intraocular pressure, and more recently, the observation of constitutive expression of COX-2 in the healthy eyes and the absence of this isoenzyme in glaucomatous eyes. These discoveries bring the hypothesis that the use of anti-inflammatory drugs may cause, as unwanted effects, ocular hypertension through the inhibition of COX expression and the reduction of prostaglandins production. The increase of intraocular pressure, even in a transient way, is a risk factor for the development of the glaucoma. In order to observe a possible ocular hypertension associated with the use of anti-inflammatory drugs, 28 beagle dogs were selected from the kennel of the Laboratory of Development of Parasiticide Products, Department of Animal Parasitology, Veterinary Institute, Universidade Federal Rural do Rio de Janeiro. On day 0 (zero) the totality of animals had their intraocular pressure measured using applanation tonometry at 8 a.m. and 4 p.m., for evaluation of intraocular pressure before treatment; on the following day 10 animals received meloxican, associated with wet feeding, on dosage of 0.2 mg Kg-1 and 0.1 mg weight on the remainder of the four days, nine dogs received prednisone, associated with wet feeding, on dosage of 1,0 mg Kg-1 during five days and nine dogs received only wet feeding. On the fifth day of treatment the totality of dogs had their intraocular pressure measured again using applanation tonometry at 8 a.m. and 4 p.m. For all groups, including control-group, the highest average values of intraocular pressure were observed on day 5 (five). The difference between intra-ocular pressure mensurations of the 08 hours and of the 16 hours was significant, independent of treatment and of the considered day. The use of both steroidal or non-steroidal anti-inflammatory were not capable of causing ocular hypertension and some factors can be incriminated, such as route of administration, dosage and duration of therapy chosen, besides genetic inheritance and absence of glaucomatous disorder between the selected dogs. / ? reconhecido o papel hipotensor ocular das prostaglandinas e mais recentemente, a observa??o da express?o de COX-2 constitutiva em olhos saud?veis e aus?ncia desta isoenzima em olhos glaucomatosos. Estas descobertas geram a hip?tese de que o uso de antiinflamat?rios apresente como efeito colateral, a hipertens?o ocular pela inibi??o da express?o da COX e diminui??o da produ??o de prostaglandinas. O aumento de press?o intra-ocular, mesmo que transit?rio, ? um fator de risco para o desenvolvimento do glaucoma. Para poss?vel observa??o da hipertens?o ocular com o uso de antiinflamat?rios, foram selecionados 28 c?es da ra?a beagle pertencentes ao Canil do Laborat?rio de Desenvolvimento de Produtos Parasiticidas do Departamento de Parasitologia Animal do Instituto de Veterin?ria da Universidade Federal Rural do Rio de Janeiro. No dia 0 (zero) todos os animais tiveram a press?o intra-ocular mensurada com o uso do ton?metro de aplana??o ?s 08 horas e ?s 16 horas, para avalia??o da press?o intra-ocular antes do tratamento; no dia seguinte dez c?es receberam meloxicam, junto ? por??o de ra??o ?mida, na dosagem de 0,2 mg/Kg e 0,1mg/Kg nos restantes quatro dias, nove c?es receberam prednisona, junto ? por??o de ra??o ?mida, na dosagem de 1,0 mg/Kg durante cinco dias e nove c?es receberam somente a por??o de ra??o ?mida. No quinto dia do tratamento todos os animais tiveram novamente a press?o intra-ocular mensurada com o uso do ton?metro de aplana??o ?s 08 horas e ?s 16 horas. Em todos os grupos, incluindo o grupo-controle, as maiores m?dias de press?o intra-ocular foram observadas no dia 5 (cinco). A diferen?a dos valores de press?o intra-ocular observada entre as medi??es das 08 horas e das 16 horas foi significativa, independente do tratamento e do dia considerado. O uso dos antiinflamat?rios esteroidal e n?o-esteroidal n?o foi capaz de causar hipertens?o ocular e alguns fatores podem ser incriminados, como via de administra??o, dosagem e dura??o do tratamento utiliz ados, al?m da heran?a gen?tica e aus?ncia de doen?a glaucomatosa nos c?es selecionados.
94

A Drosophila Disease-Model for Transthyretin-associated Amyloidosis

Pokrzywa, Malgorzata January 2008 (has links)
Amyloidoses comprise a group of gain-of-toxic function protein misfolding diseases, in which normally soluble proteins in their functional state undergo conformational changes into highly organized and generally intractable thread-like aggregates, termed amyloid fibrils. These structures accumulate predominantly in the extracellular space but growing evidence suggests that amyloids may start to form intracellularly. At least 26 different human proteins, intact or in fragmented form, are known to form amyloid, which is linked with many debilitating neurodegenerative diseases such as Alzheimer’s disease (AD), Creutzfeldt-Jakob disease, and transthyretin (TTR)-related amyloidosis (ATTR). In this work, we focus on ATTR, which is one of the most frequent systemic amyloid diseases. A functional link was established between hereditary ATTR, a severe and fatal disorder and the enhanced propensity of the human plasma protein transthyretin (TTR) to form aggregates, caused by single point mutations in the TTR gene. The disease is heterogeneous and clinical symptoms vary from cardiomyopathy to progressing sensorimotor polyneuropathy depending on TTR variant involved and the amyloid deposition site. Despite the fact that TTR-derived amyloid accumulates in different organs such as heart, kidney, eyes, and predominantly in the peripheral nerves of ATTR patients, the exact mechanism of the disease development is not understood. In contrast to the case of AD, it has been difficult to generate an animal model for ATTR in transgenic mice that would be useful in understanding TTR aggregation processes and the mechanisms of the associated toxicity as these mice did not develop any neuropathic phenotype besides amyloid deposits. Therefore, we created a disease-model in Drosophila due to its huge repertoire of genetic techniques and easy genotype – phenotype translation, as well as its success in modeling human neurodegeneration. We have generated transgenic flies that over-express the clinical amyloidogenic variant TTRL55P, the engineered variant TTR-A (TTRV14N ⁄ V16E), and the wild-type protein. All TTR variants were found in the secreted form in the hemolymph where misfolding occurred and depending on the pool of toxic species, the fate of the fly was decided. Within a few weeks, both mutants (but not the wild-type TTR) demonstrated a time-dependent aggregation of misfolded molecules in vivo. This was associated with neurodegeneration, change in wing posture, attenuation of locomotor activity including compromised flying ability, and shortened life span. In contrast, expression of the wild-type TTR had no discernible effect on either longevity or fly behavior. In this work, we also addressed the correlation between TTR transgene dosage and thus, protein levels, with the severity of the phenotypes observed in TTR-A flies which developed a “dragged wing” phenotype. Remarkably, we established that degenerative changes such as damage to the retina strictly correlated with increased levels of mutated TTR but inversely with behavioral alterations and the dragged wing phenotype. We characterized formation of aggregates in the form of 20 nm spherules and amyloid filaments intracellularly in the thoracic adipose tissue and brain glia (both tissues that do not express the transgene). Moreover, we detected a fraction of neurotoxic TTR-A in the hemolymph of young but not old flies. We proposed that these animals counteract formation and persistence of toxic TTR-A species by removal from the circulation into intracellular compartments of glial and fat body cells and this is part of a mechanism that neutralizes the toxic effects of TTR. We validated the fly model for ATTR by applying a genetic screen during study of modifier genes. We found Serum amyloid P component (a product of the APCS gene) as a potent modifier of TTR amyloid-induced toxicity that was effective in preventing the apoptotic response in cell culture assay and capable of reducing the dragged wings when co-expressed in TTR-A flies. Finally, we optimized this fly model in order to screen for therapeutic compounds effective against ATTR. Feeding assays showed the effectiveness of several compounds among known native-state kinetic stabilizers of TTR against its aggregation. We described several early endpoints in this model, which can be used as a rapid and cost-effective method for optimizing concentrations and pre-screening of drug candidates. As the proof of principle, by feeding flies with increasing doses of diflunisal analogue (an FDA-approved Non-Steroidal Anti-Inflammatory Drug) a dose-dependent reduction of the dragged wings was observed.
95

Cyclooxygenase-2 inhibitors and knee prosthesis surgery

Meunier, Andreas January 2008 (has links)
Adverse effects of cyclooxygenase (COX) inhibitors on bone healing have previously been demonstrated in diaphyseal fracture models in animals. In spite of that, they are widely used as postoperative analgesics in orthopaedic surgery. After joint replacement, a bone repair process starts at the interface between bone and cement. If this process is disturbed, the prosthesis may never become rigidly fixed to the bone, leading to migration and with time loosening. This thesis investigates the effects of a selective COX-2 inhibitor (parecoxib or celecoxib) on bone healing in metaphyseal bone in a rat model and on knee prosthesis migration after total knee replacement, as measured with radiostereometric analysis. Blood loss, postoperative recovery, and the 2-year subjective outcome, were also measured. In addition, a hemoglobin dilution method for blood loss estimation, used in this thesis, was evaluated. In the first study, pull-out force of a screw inserted in metaphyseal bone of the tibia in rats was only marginally decreased by parecoxib after 7 days but not after 14 days. In the second and third study, celecoxib treatment resulted in less pain postoperatively in conjunction with total knee replacement (TKR), but no effects were seen on blood loss, range of motion, subjective outcome, or prosthesis migration after 2 years. Comparing the true blood loss of blood donors with the blood loss estimated by the hemoglobin dilution method, this method was found to underestimate the true blood loss. It is therefore not suitable for calculation of the absolute blood loss volume, but may be used for a rough estimate. In summary, celecoxib and presumably other cyclooxygenase inhibitors seems not likely to increase the risk of prosthesis loosening.
96

Concentration synoviale et plasmatique de diclofénac après son utilisation topique et orale chez le cheval

Bolduc, Marissa January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
97

Cyclooxygenase-2 inhibitors and knee prosthesis surgery /

Meunier, Andreas, January 2008 (has links) (PDF)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2008. / Härtill 4 uppsatser.
98

SMAD3 in embryonic patterning, mesoderm induction, and colorectal cancer in the mouse

Wieduwilt, Matthew J. January 2003 (has links) (PDF)
Thesis (Ph. D.) -- University of Texas Southwestern Medical Center at Dallas, 2003. / Vita. Bibliography: 180-208.
99

Σχεδιασμός, σύνθεση και αποτίμηση βιολογικής δραστικότητας νέων στεροειδών εστέρων με τροποποιημένους αλκυλιωτικούς παράγοντες

Παπακωνσταντίνου, Ιωάννα 12 April 2013 (has links)
Εξήντα έξη χρόνια μετά την εμφάνιση της πρώτης δημοσίευσης που αφορούσε στη θεραπεία με τη χρήση μουσταρδών αζώτου και ενώσεις που ανήκουν στη θεραπευτική αυτή κατηγορία, όπως το κυκλοφωσφαμίδιο και η μελφαλάνη εξακολουθούν να αποτελούν πρώτης γραμμής χημειοθεραπευτικούς παράγοντες τόσο κατά της λευχαιμίας όσο και έναντι άλλων συμπαγών όγκων. Οι διλειτουργικοί αλκυλιωτικοί παράγοντες, κατηγορία στην οποία ανήκουν και οι μουστάρδες αζώτου, επάγουν το θάνατο των καρκινικών κυττάρων και κατά συνέπεια και την κυτταροτοξική τους δράση μέσω της δημιουργίας διαμοριακών χιαστί τύπου δεσμών μεταξύ των κλώνων του DNA. Οι φαρμακολογικές τους δράσεις σχετίζονται κυρίως με την σύνθεση του DNA των διαιρούμενων κυττάρων, προκαλώντας ουσιαστικά μια γενική αναστολή της κυτταρικής διαίρεσης. Ωστόσο, εκτός από την αναμενόμενη και επιθυμητή θεραπευτική δράση, προκαλούν τοξικές παρενέργειες, οι οποίες σχετίζονται με μεταλλαγή των κυττάρων της αρχέγονης σειράς, εμφάνιση καρκινογένεσης και τερατογένεσης. Το εύρος των μειονεκτημάτων που παρουσιάζουν και ειδικά η συστηματική τοξικότητα σε συνδυασμό με την υψηλή χημική in vivo δραστικότητα τους και την μειωμένη εκλεκτικότητα τους, είχαν ως αποτέλεσμα τον περιορισμό της χρήσης τους. Παρόλα αυτά κατέχουν εξέχουσα θέση στη θεραπευτική έναντι μιας μεγάλης ποικιλίας τύπων καρκίνου, συμπεριλαμβανομένου και των αιματολογικών νεοπλασμάτων. Στην προσπάθεια επίλυσης του προβλήματος της αυξημένης τοξικότητας και της απουσίας εκλεκτικότητας των ενώσεων της κατηγορίας αυτής, διάφορες μουστάρδες αζώτου συζεύχθηκαν μέσω εστερικού δεσμού με ποικίλους στεροειδικούς σκελετούς, στρατηγική που αποδείχθηκε ουσιαστικά ιδιαιτέρως αποτελεσματική. Αποτελέσματα μελετών τόσο της ερευνητικής μας ομάδας όσο και άλλων, υποστηρίζουν πως ο στεροειδικός σκελετός δεν μπορεί πλέον να θεωρηθεί μόνο ως απλός φορέας για την αποτελεσματική μεταφορά της αλκυλιωτικής ομάδας στις θέσεις στόχους του DNA, εφόσον μικρές δομικές τροποποιήσεις του επιφέρουν σημαντικές διαφοροποιήσεις στην αντιλευχαιμική δράση των τελικών στεροειδών εστέρων. Επιπρόσθετα, οι μελέτες αυτές έδειξαν ότι η παρουσία της –NHCO- ομάδας είτε ως ενδοκυκλικής λακταμικής είτε ως εξωκυκλικής αμιδικής στον Δ-δακτύλιο του στεροειδικού τμήματος είναι καθοριστικός παράγοντας για την εμφάνιση κυτταροτοξικής ή αντινεοπλασματικής δράσης στεροειδών εστέρων της χλωραμβουκίλης και αναλόγων αυτής. Μέχρι σήμερα έχει προκύψει ένας εκτεταμένος αριθμός στεροειδών εστέρων, από την σύζευξη απλών και τροποποιημένων στεροειδών με αρκετές διαφορετικές μουστάρδες αζώτου. Η πλειονότητα αυτών των παραγώγων έχουν υποβληθεί σε in vitro και in vivo βιολογικές δοκιμές έναντι των λευχαιμίων Ρ388 και L1210 και αρκετά από αυτά έχουν αποδειχθεί αποτελεσματικοί αντινεοπλασματικοί παράγοντες. Σε μια πρόσφατη 3D-QSAR μελέτη τριάντα οκτώ στεροειδών εστέρων τριών διαφορετικών μουσταρδών αζώτου με απλούς και τροποποιημένους στεροειδικούς σκελετούς, έγινε προσπάθεια διερεύνησης των 3D σχέσεων χημικής δομής-βιολογικής δραστικότητας, με σκοπό την εύρεση των απαραίτητων στερεοηλεκτρονικών χαρακτηριστικών των ενώσεων που συμβάλλουν στην εκδήλωση της αντιλευχαιμικής δράσης των. Η ανάλυση στηρίχθηκε στην χρήση των μεθοδολογιών CoMSIA και CoMFA. Τα δεδομένα που ελήφθησαν από τις 3D-QSAR αναλύσεις αξιοποιήθηκαν στη συνέχεια από ένα υπολογιστικό πρόγραμμα de novo σχεδιασμού και ανακάλυψης νέων βιοδραστικών μορίων, την εφαρμογή LeapFrog. Με βάση τα είκοσι βελτιωμένα στεροειδικά εστερικά παράγωγα που προτάθηκαν από το LeapFrog, επιλέχθηκαν να σχεδιαστούν και να συντεθούν οι ακόλουθες αρωματικές μουστάρδες αζώτου: α) 2-[π-Ν,Ν-δις(2-χλωροαιθυλ)αμινοφαινυλο]βουτυρικό οξύ (7), β) 2-ακεταμιδο-2-[π-Ν,Ν-δις(2-χλωροαιθυλ)αμινοφαινυλο]οξικό οξύ (30), γ) 2-ακεταμιδο-2-[ο-Ν,Ν-δις(2-χλωροαιθυλ)αμινοφαινυλο]οξικό οξύ (31) και δ) το 3-ακεταμιδο-3-[π-Ν,Ν-δις(2-χλωροαιθυλ)αμινοφαινυλο] προπανοϊκό οξύ (42), καθώς και τα εστεροποιημένα παράγωγα αυτών, με επιλεγμένους απλούς και τροποποιημένους στεροειδικούς σκελετούς. Η σύζευξη των νεων μουσταρδών με επιλεγμένες στεροειδικές αλκοόλες απέδωσε δεκαεπτά νέα εστερικά ανάλογα, η σύνθεση των οποίων είχε ως απώτερο σκοπό τη βελτίωση του θεραπευτικού δείκτη των μουσταρδών αζώτου καθώς και τον εμπλουτισμό της βιβλιοθήκης των αποτελεσμάτων που αφορούν στη σχέση χημικής δομής-βιολογικής δραστικότητας των ενώσεων της κατηγορίας αυτής. Συγκεκριμένα, για τη σύνθεση των παραπάνω μουσταρδών αζώτου, εφαρμόστηκε η κλασσική μεθοδολογία σύνθεσης. Ωστόσο, αυτή αποδείχθηκε αποδοτική μονό κατά τη σύνθεση της μουστάρδας 7, παρέχοντας το τελευταίο σε συνολική απόδοση 45%. Για τις υπόλοιπες μουστάρδες ακολουθήθηκαν εναλλακτικές πορείες σύνθεσης λόγω προβλημάτων που παρουσιάστηκαν κατά την εφαρμογή της κλασσικής μεθοδολογίας. Κρίσιμο στάδιο κατά τη σύνθεση των μουσταρδών αζώτου 30 και 31, αποτέλεσε η αρχική προστασία της ελεύθερης αμινομάδας της DL-α-φαινυλγλυκίνης (16) που χρησιμοποιήθηκε ως πρώτη ύλη της συνθετικής πορείας. Η διερεύνηση και η βελτιστοποίηση των πειραματικών συνθηκών ήταν απαραίτητη και κατά το στάδιο της χλωρίωσης των Ν,Ν-δις(2-υδροξυαιθυλ)-παραγώγων 26 και 27 για τον σχηματισμό της χαρακτηριστικής Ν,Ν-δις(2-χλωροαιθυλαμινο)-ομάδας των παραγώγων 30 και 31. Κατά τη σύνθεση του 3-ακεταμιδο-3-[π-Ν,Ν-δις(2-χλωροαιθυλ)αμινοφαινυλο]προπανοϊκού οξέος (42) ήταν απαραίτητη η βελτιστοποίηση παρασκευής των ενδιαμέσων 33 και 37. Μετά από διερευνητικές προσπάθειες κατέστη εφικτή η βελτίωση της απόδοσης σύνθεσης του παραγώγου 33 από 54% σύμφωνα με τη βιβλιογραφία σε 98%, καθώς και η σύνθεση του ακετάμιδο παραγώγου 37 τόσο σε λιγότερα συνθετικά στάδια και σε καλύτερη απόδοση σε σχέση με τα δημοσιευμένα βιβλιογραφικά δεδομένα. Σε επόμενο στάδιο της μελέτης σχεδιάσθηκε η εστεροποίηση των μουστάρδων 7, 30 και 42 με επιλεγμένους στεροειδικούς σκελετούς. Για τη σύνθεση των τελικών εστερικών στεροειδικών παραγώγων εφαρμόστηκε η μέθοδος των μικτών ανυδριτών, η οποία περιλαμβάνει την αντίδραση της αρωματικής μουστάρδας αζώτου με ελαφρά περίσσεια 2,4,6-τριχλωροβενζοϋλοχλωρίδιου παρουσία τριαιθυλαμίνης, το σχηματισμό του αντίστοιχου μικτού ανυδρίτη και στη συνέχεια in situ αντίδρασή του με τη στεροειδική αλκοόλη παρουσία 4-διμεθυλαμινοπυριδίνης. Τελικώς κατέστη εφικτή η σύνθεση δεκαεπτά τελικών στεροειδών εστέρων από τη σύζευξη των μουσταρδών αζώτου, 7 και 42 με επιλεγμένες στεροειδείς αλκοόλες. Παρά τις διερευνητικές προσπάθειες που καταβλήθησαν δεν κατέστη εφικτή η εστεροποίηση της μουστάρδας 30. Το σύνολο των τελικών στεροειδών εστέρων προωθήθηκαν σε βιολογικές μελέτες για την αποτίμηση της αντινεοπλασματικής τους δράσης. Τα διαθέσιμα αποτελέσματα αυτών των μελετών σχετίζονται με τα έντεκα στεροειδικά εστερικά παράγωγα της μουστάρδας 7 (2-PHE-BU). Τα μελετηθέντα αυτά παράγωγα επέδειξαν μειωμένη τοξικότητα και μια οριακή αντινεοπλασματική δραστικότητα έναντι της λευχαιμίας Ρ388, στην οποία είχαν μελετηθεί, συγκριτικά με την ελέυθερη αρωματική μουστάρδα (2-PHE-Bu). Ωστόσο, τα ληφθέντα βιολογικά αποτελέσματα ήταν υποδεέστερα των αντίστοιχων δεδομένων που είχαν συλλεχθεί κατά τη μελέτη του PHE και των στεροειδικών εστέρων αυτού έναντι και πάλι της λευχαιμίας Ρ388. Το γεγονός αυτό πιθανόν να οφείλεται στη μειωμένη ενζυμική υδρόλυση που υφίστανται in vivo τα παράγωγα αυτά, λόγω της στερεοχημικής παρεμπόδισης που προκαλεί η αιθυλική αλυσίδα γύρω από τον εστερικό δεσμό σύνδεσης μουστάρδας-στεροειδούς, γεγονός που συνεπάγεται μειωμένη απελευθέρωση της μουστάρδας αζώτου. Στο σημείο αυτό αξίζει να αναφερθεί πως αν και, τόσο οι νέες αρωματικές μουστάρδες αζώτου, όσο και τα στεροειδικά τους παράγωγα είχαν προταθεί ως υποψήφια παράγωγα με βελτιωμένη βιοδραστικότητα κατά την πραγματοποίηση de novo σχεδιασμού από το υπολογιστικό πρόγραμμα LeapFrog, τα αποτελέσματα των βιολογικών δοκιμών δεν επιβεβαιώσαν τις συγκεκριμένες ποτάσεις. Πιθανότατα, παράμετροι που δεν ελήφθησαν υπόψη κατά τον de novo σχεδιασμό από το LeapFrog, όπως η μεταβολική τροποποίηση των ενώσεων να εμπλέκονται και να καθορίζουν την βιοδραστικότητα του τελικών στεροειδικών εστέρων. Θεωρείται ότι μια αναθεώρηση κρίσιμων παραμέτρων όπως η χημική ποικιλομορφία και ο αριθμός των ενώσεων που εισέρχονται ως δεδομένα στις μελέτες 3D-QSAR μπορεί να αποδώσει μεγαλύτερης αξιοπίστιας μοντέλα CoMFA και CoMSIA. Τα νέα αυτά μοντέλα κατά την εισαγωγή τους σε υπολογιαστικά προγράμματα de novo σχεδιασμού μπορούν να συμβάλλουν στο σχεδιασμό νεών ενώσεων με πιθανά υπέρτερη βιοδραστικότητα. / Sixty-six years after the serendipitous discovery and the first publication referred to nitrogen mustard therapy, nitrogen mustards such as cyclophosphamide and melphalan are still front-line chemotherapeutic agents for the treatment of leukemia and various solid tumors. Several chemotherapeutics act as DNA-damaging agents resulting in cell cycle arrest and cell death of the uncontrollably proliferating cancer cells. Among them, bifunctional DNA alkylating agents, such as the nitrogen mustards, form intrestrand crosslinks (ICLs), extremely cytotoxic lesions, blocking DNA replication and transcription. However, cellular responses triggered by ICLs can cause resistance in tumor cells, limiting the efficacy of such treatment. Cytotoxicity, mutagenesis, and clastogenesis are attributed to their ability to damage DNA. Although, these drugs remain some of the most commonly prescribed chemotherapies for the treatment of various solid and hematological malignancies, particularly in combination with other classical or target therapeutics in multi-agent regimens, severe side effects on normal tissues comprise drawbacks of their use. These are attributed to their low selectivity to alkylate specific DNA bases due to their high inherent reactivity, resulting in the non-specific alkylation of other cellular nucleophilic species such as amino acid residues or low molecular weight thiols. Several approaches have been explored to reduce the toxicity and increase the therapeutic efficacy of nitrogen mustards. Among them, the generation of DNA-directed alkylating agents via the chemical linkage of nitrogen mustards with molecules of increased DNA-binding affinity and the synthesis of nitrogen mustard prodrugs led to interesting results. The chemical linkage of nitrogen mustards to carrier molecules (e.g steroids) with affinity for specific binding sites (nuclear receptors) has been used aiming at the improvement of the antineoplastic treatment. Our ongoing studies in this field have demonstrated that steroidal esteric derivatives of aromatic nitrogen mustards increase the damaging effects on specific DNA sequences and achieve better selectivity and reduced toxicity compared to nitrogen mustards themselves. Steroidal skeletons, which incorporate a –NHCO- moiety are considered more appropriate modules than the common or non-modified steroids, since their esters with aromatic nitrogen mustards, such as chlorambucil and its analogs, have been proved potent antileukemic agents. To this direction, our group has published a series of studies related with steroidal esters of aromatic nitrogen mustards as antineoplastic, especially antileukemic agents. Our efforts have succeeded in the identification of potent and promising derivatives with enhanced activity and reduced toxicity compared to the corresponding nitrogen mustards against in vitro and in vivo experimental tumors. Extensive structure-activity relationship (SAR) studies have demonstrated unique structural features of both the steroidal part and the nitrogen mustard which contribute substantially to the bioactivity of the target steroidal esters Furthermore, recent 3D QSAR/CoMFA and CoMSIA studies led to the generation of related models which indicated the influence of stereoelectronic and physicochemical parameters on the antileukemic activity of target compounds. The reliability of both models was evaluated and their predictive ability on the activity of a test set of compounds proved satisfactory. Furthermore, based on the proposed CoMFA model and using the de novo ligand design routine LeapFrog of SYBYL, a series of candidate molecules with potentially optimal bioactivity was proposed, creating new challenges in further investigation of this class of compounds. Prompted by the aforementioned results and extending our structure-activity relationship studies, we decided to investigate if the incorporation of in silico predictive nitrogen mustards on various simple and modified steroids might result to steroidal esters with improved antineoplastic activity. The selection of the nitrogen mustards which were synthesized and used in this study was based on the predictive antileukemic activity of their corresponding steroidal esters and the synthetic accessibility of the intermediate and target compounds. Thus, we designed and synthesized a new series of steroidal esters containing the aromatic nitrogen mustards 2-[4-N,N-bis(2-chloroethyl)amino-phenyl]butanoic acid (2-PHE-BU, 7), 2-acetamido-2-[p-N,N-bis(2-chloroethyl)amino-phenyl]acetic acid (30), 2-acetamido-2-[o-N,N-bis(2-chloroethyl)amino-phenyl]acetic acid (31) and 3-acetamido-3-[p-N,N-bis(2-chloroethyl)amino-phenyl]propanoic acid (42). The chemical linkage of nitrogen mustards 7 and 42 with simple and modified steroids led to the synthesis of seventeen new steroidal esters aiming at the investigation of new compounds with enhanced antineoplastic activity and higher therapeutic index. The synthesis of the aforementioned nitrogen mustards was based on a classic synthetic approach. However, this procedure proved efficient only for the synthesis of compound 7, in an overall yield of 45%. Key step for the synthesis of nitrogen mustards 30 and 31 was the protection of the free amino-group of DL--phenyglycine. Optimization of the experimental conditions were also necessary for the chlorination of N,N-bis(2-hydroxyethyl) intermediates 26 and 27, which led to the corresponding nitrogen mustards 30 and 31. During the synthesis of the 3-acetamido-3-[p-N,N-bis(2-chloroethyl)amino]propanoic acid (42), optimization of the procedure for the preparation of the intermediates 33 and 37 was also necessary. Our attempts resulted in the preparation of compound 37 in less steps and higher yield (98%) compared to that referred in the literature. The synthesis of the final steroidal esteric derivatives was based on the well established method of mixed anhydrides, which involves the reaction of the aromatic nitrogen mustard with a slight excess of 2,4,6-trichlorobenzoyl chloride in the presence of triethylamine, followed by the addition of steroidal alcohol in the presence of 4-dimethylaminopyridine. The newly synthesized alkylating steroidal esters exhibited reduced toxicity and slightly improved antileukemic activity against P388 leukemia bearing mice compared to the free nitrogen mustard 2-PHE-BU. Nevertheless, they did not prove superior to already synthesized, structurally related steroidal esters of PHE indicating that the enzymatic hydrolysis and the liberation of the nitrogen mustard in vivo is possibly disfavored due to the steric hindrance of the ethyl group around the formed ester bond. Nevertheless, the biological results obtained in the present study clearly indicate that except of the important stereoelectronic requirements which are considered and incorporated as data in LeapFrog routine, other parameters are possibly implicated and determine the bioactivity of the target steroidal esters. We expect that a careful revision of the implicated parameters such as the chemical diversity and the number of the tested compounds will allows us the generation of new CoMFA and CoMSIA models which subsequently will contribute to higher predicted reliability of the in silico design by software packages such as LeapFrog.
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Avaliação farmacocinética, hematológica e espermática de pôneis tratados com meloxicam / Pharmacokinetics, hematological and spermatic parameters in ponies treated with meloxicam

Pozzobon, Ricardo 15 July 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most used drugs in veterinary medicine. Most of the original NSAIDs inhibit primarily cyclooxygenase-1 (COX-1) and cause adverse effects such as gastrointestinal ulcers, kidney and liver damage. When the formerly supposed anti-inflammatory COX-2 enzyme was discovered, NSAIDs were developed to selectively inhibit this enzyme. Today it is known that COX-2 is not exclusively expressed in inflammatory conditions; it also has physiologic functions in tissues such as brain, male and female reproductive tracts. Several horses, such as stallions, are treated with some NSAID, and many times these treatments are prolonged as in osteoarthritis and laminitis. In horses, there is still little information about the effects of COX-1 and COX-2 selective NSAIDs on the reproductive and cardiovascular systems. Pharmacokinetic information of NSAIDs, like meloxicam, in different health conditions and horse breeds may explain differences in efficiency and/or toxicity. This study evaluated meloxicam pharmacokinetics on 3 groups with 3 animals each: a group of ponies with induced synovitis, a group of healthy ponies and a group of healthy horses. All animals were treated with the recommended dosage (0.06 mg/kg, PO) of meloxicam. Plasma was obtained from blood samples collected before (time 0), 15 and 30 minutes, and 1, 2, 4, 8, 12 and 24 hours after medication. The time to reach the maximum plasma concentration (Tmax) was longest (P<0.05) in horses and the maximum concentration (Cmax) was highest (P<0.05) in healthy ponies. The initial plasma concentrations were achieved more quickly (P<0.05) in both ponies groups. In a second study, the effect of meloxicam (preferential COX-2 NSAID) and ketoprofen (unspecific NSAID) was evaluated on hematological and biochemical variables, on the gastric mucosa and on semen quality of 6 healthy pony stallions. The ponies were treated for 30 days and then the experiment was repeated a second time changing the ponies group in a latin square design. The stallions were distributed equally into 3 groups; one was treated with meloxicam (0.6 mg/kg oral administration, PO; n=6), another with ketoprofen (2.2 mg/kg, PO; n=6, positive control) and the negative control group (n=6) received no treatment. Blood samples were obtained once a week for six weeks, beginning before treatment and extending until 1 week after the treatment ended to evaluate hematologic, coagulation and biochemical (AP, AST and GGT) profiles. Gastroscopic evaluation was determined 1 week before and 1 week after the treatment ended. Semen was collected and evaluated twice a week for 16 weeks: before treatment began (week 0), during 4 weeks of treatment (weeks 1-4), and 10 weeks after the treatment ended (weeks 5-15). Concentration of total prostaglandins (PGs) was measured in the seminal plasma of ejaculates collected before (week 0), during (1 to 4 weeks) and after treatment (week 5 and week 15). The treatments did not alter any evaluated hematological and biochemical parameter as well as on the gastric mucosa, but there was a time effect on fibrinogen, pro-thrombin time and activated partial thromboplastin time. Meloxicam treatment caused more (P<0.05) damage to the sperm membrane integrity and decreased (P<0.05) membrane function and total PGs concentration. A significant increase (P<0.05) in tail defects also was observed 2 weeks after treatment ended. In summary, pharmacokinetics differed between healthy ponies and those with synovitis. This may be the result of drug migration to the injury site. Meloxicam absorption was faster in ponies. No influence of the treatments was observed on the hematological or biochemical parameters as well as on gastric mucosa. Thirty day long meloxicam treatment lowered PGs in seminal plasma and affected semen quality. This suggests a physiological function of COX-2 in the stallion s reproductive tract. / Os anti-inflamatórios não esteroidais (AINEs) estão entre os fármacos mais utilizados na medicina veterinária. A maioria deles produz efeitos colaterais, como úlceras gastrointestinais, lesões renais e hepáticas, por inibirem a ciclooxigenase-1 (COX-1). Com a descoberta da COX-2, passaram a ser desenvolvidos AINEs para inibir seletivamente esta enzima, tida até pouco tempo como inflamatória. Porém, hoje se sabe que a COX-2 não é expressa exclusivamente em condições inflamatórias, mas também em funções fisiológicas em vários tecidos, como o cerebral, reprodutivo feminino e masculino. Vários eqüinos, como garanhões, são freqüentemente tratados com algum AINE, e muitas vezes esses tratamentos são prolongados como nos casos de osteoartrite e laminite. Além disto, são escassas as informações sobre os efeitos causados tanto pelos AINEs com inibição inespecífica de COX, como pelos ditos seletivos para a COX-2, especialmente sobre o sistema reprodutivo e cardiovascular de eqüinos. O conhecimento da farmacocinética de novos AINEs, como o meloxicam em diferentes condições de saúde e tamanho de eqüinos poderia explicar a sua eficácia ou efeito tóxico diversos. Desta forma, o estudo da farmacocinética do meloxicam oral foi realizado com três grupos distintos de eqüinos com três animais cada. Um grupo formado por pôneis com sinovite induzida, um grupo com pôneis saudáveis e outro grupo com cavalos saudáveis. Todos os animais foram tratados com a dose indicada (0,6 mg/kg via oral). As amostras de sangue para obtenção do plasma foram coletadas antes (tempo 0), 15, 30 minutos e 1, 2, 4, 8, 12 e 24 horas pós-medicação. O tempo da concentração máxima do fármaco (Tmax) foi mais tardio (P<0,05) nos cavalos e a concentração plasmática máxima (Cmax) foi maior (P<0,05) nos pôneis saudáveis. As primeiras concentrações plasmáticas foram atingidas mais rapidamente (P<0,05) nos grupos de pôneis. Para avaliar o efeito do meloxicam (AINE com ação preferencial sobre a COX-2) sobre os parâmetros hematológicos, bioquímicos, na mucosa gástrica, e sobre a qualidade do sêmen eqüino foram utilizados seis garanhões pôneis. Estes foram distribuídos em três grupos, sendo um tratado com meloxicam (0,6 mg/kg via oral), outro com cetoprofeno como controle positivo (2,2 mg/kg via oral; inibidor inespecífico de COX) durante 30 dias e um terceiro grupo não recebeu nenhum tratamento constituindo o grupo controle negativo. O experimento foi repetido três vezes alternando-se os pôneis de grupos num delineamento quadrado latino. Amostras de sangue foram coletadas antes (semana zero), durante (semanas um a quatro) e uma semana após o fim do tratamento (semana cinco) para determinação dos parâmetros hematológicos (hemograma e coagulograma) e bioquímicos (fosfatase alcalina - AP, aspartato aminotransferase - AST e gama-glutamil transferase - GGT). Também foram realizadas gastroscopias antes (semana zero) e após o final do tratamento (semana cinco). O sêmen foi coletado e avaliado duas vezes por semana antes (semana zero), durante (semanas um a quatro) e por 11 semanas após o final do tratamento (semanas cinco a 15). A concentração de prostaglandinas totais no plasma seminal foi avaliada nas semanas zero a cinco e na semana 15. Os tratamentos não modificaram nenhum parâmetro hematológico, bioquímico e gástrico avaliado, mas o tempo de coleta influenciou o fibrinogênio, tempo de pró-trombina e tempo de tromboplastina parcial ativada. O grupo tratado com meloxicam apresentou mais (P<0,05) espermatozóides com lesões de membrana e com diminuição da funcionalidade da membrana, bem como aumento significativo (P<0,05) de defeitos de cauda e diminuição (P<0,05) na concentração de prostaglandinas totais no plasma seminal, comparado aos grupos cetoprofeno e controle. Os parâmetros da farmacocinética diferiram entre os pôneis saudáveis e com sinovite. Isto pode ser atribuído a uma possível migração do fármaco para o local da lesão. A absorção do meloxicam foi mais rápida nos pôneis. Os tratamentos não influenciaram os parâmetros hematológicos, de coagulação, bioquímicos e na mucosa gástrica. O tratamento por 30 dias com meloxicam diminui a concentração de prostaglandinas totais no plasma seminal e interfere negativamente na qualidade do sêmen, sugerindo uma ação fisiológica da COX-2 no tecido reprodutivo de garanhões.

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