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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

8-methoxypsoralen-mediated impairment of human lymphocyte proliferation in vitro in the absence of ultraviolet irradiation : immunological and biochemical mechanisms /

Cox, George Warren January 1987 (has links)
No description available.
2

The effect of 8-methoxypsoralen on the cyclic AMP concentration of normal human fibroblasts in vitro /

Albrightson, Christine Ruth January 1983 (has links)
No description available.
3

The disposition of 8-methoxypsoralen in the rat /

Rogers, Sharon Lee January 1984 (has links)
No description available.
4

The pharmacokinetics and metabolism of 8-methoxypsoralen in the rat /

Mays, Dennis Charles , January 1984 (has links)
No description available.
5

Interstrand Crosslinks - Induction and repair

Vare, Daniel January 2012 (has links)
DNA crosslinking agents exhibit a variety of DNA lesions, such as monoadducts, DNA-DNA interstrand or intrastrand crosslinks or DNA-protein crosslinks. Agents that produce interstrand crosslinks (ICLs) exist naturally and are widely used in chemotherapy. Therefore, it is important to understand how the lesions induced by these agents are repaired. In bacteria, the repair is mainly dependent on nucleotide excision repair (NER) together with homologous recombination (HR) or translesion synthesis (TLS). In human cells, it is not clear how these lesions are repaired, and it is believed to be a more complicated process in which NER does not play as important a role as in prokaryotes. Here, we investigated the repair mechanisms mainly after treatment with psoralen but also with acetaldehyde, cisplatin and mitomycin C in some studies. As expected from studies on plasmids and in bacteria, we used new techniques to confirm that various ICL-inducing agents block replication fork elongation in mammalian cells. We also found that the replication fork was unable to bypass these lesions. We confirmed that ERCC1/XPF and the HR proteins BRCA2 and XRCC2/3 are vital for protection against ICL treatments. These proteins were also found to be equally important for the repair of monoadducts. To better understand ICL repair in mammalian cells, we developed a method to study the induction and unhooking of ICL in human fibroblasts. We found that ICLs were repaired and that 50% of the induced ICLs were unhooked within 3 hours following exposure. Additionally, we determined that XPA, but not XPE, is involved in ICL unhooking, although not affecting lethality. A step in ICL repair is the formation of double-strand breaks (DSBs), and we identified a replication-dependent formation of DSBs following ICL treatment. Furthermore, ERCC1/XPF was not necessary for DSB formation. The repair of these DSBs was performed by HR and involved ERCC1/XPF. Additionally, we were able to quantify the ICL unhooking in human fibroblasts and found that they can unhook ~2500 ICL/h. We also determined that a dose of approximately 400 ICL/cell is lethal to 50% of the cells, indicating that ICL unhooking is not the most critical step during the repair process. / DNA-skadande ämnen är vanligt i cancerbehandling, då snabbt växande celler, såsom cancerceller är betydligt känsligare än normala celler för DNA skador. En grupp av ämnen som vanligen används i cancerbehandling är korsbindare av DNA. Dessa ämnen kommer reagera två gånger med DNA och skapa två bindningar mitt emot varandra. DNA strängen, som består av två delar, måste kunna separeras och kopieras (replikation) på ett tillförlitligt sätt för att cellerna ska kunna dela sig och bli flera. DNA strängen måste också kunna dela sig och bli avläst rätt för att nya proteiner ska kunna bildas (transkription). När korsbindarna har bundit till DNA strängarna, hindrar detta deras separation och därigenom förhindras även avläsningen och kopieringen.  För att göra undersökningarna av DNA korsbindande ämnen ännu lite svårare, så ger korsbindare flera olika typer av skador. Dels kan det bli flera olika typer av korsbindningar, både mellan två DNA-strängar (ICL) vilket är den farligaste och mest svårreparerade typen, men det kan också ske inom samma DNA-sträng (intrastrand crosslink) eller mellan en DNA-sträng och ett protein (DNA-protein crosslink). Korsbindare kan även bilda enbindningsskador (monoaddukt), vilket innebär den bara binder en gång till DNA. För att cellen ska kunna överleva, så måste den reparera skadorna och ta bort korsbindningen eller monoaddukten. Hur detta sker i människor är inte helt klarlagt men det verkar som det sker i flera steg. Till att börja med klipps DNA sönder i ena strängen på båda sidorna om korsbindningen, detta gör att den kvarvarande delen av korsbindningen kan böjas bort. Därefter kommer cellen att skapa nytt DNA för att fylla mellanrummet som bildats. Cellen använder sig av den andra DNA strängen som mall för att sätta in rätt DNA baser, men i fallet med korsbindande ämnen så är även den strängen skadad och därför finns det en stor risk för att fel DNA baser sätts in och då uppstår mutationer. Nästa steg är att klippa den kvarvarande delen av korsbindningen, även denna gång skapas ett mellanrum som måste fyllas med nya baser. Den första artikeln i avhandlingen handlar om att försöka reda ut om det är ICLen eller monoaddukten som är orsak till olika effekter som påträffas efter behandling med korsbindande ämnen. Det vi fann var att även om det bara var från ICLs som vi kunde mäta en effekt på replikationen, så fick vi nästan lika stark effekt från monoaddukterna, som från ICL, för en av de vanligast använda markörerna (kännetecknen) för båda DNA strängarna var brutna på samma ställe (dubbelstränsbrott). Detta berodde dock inte på att även monoaddukterna skapade dubbelsträngsbrott, utan på att markören vi använde var ospecifik. Vi fann även att även om ICLs har mycket större effekt än monoaddukten på cellens överlevnad m.m., så kan man inte bortse ifrån effekten av monoaddukten och att den troligen har en betydande roll för de korsbindande ämnen som endast ger en liten del ICLs. I artikel två har vi utvecklat en ny metod, som gör det möjligt att mäta hur många ICLs som bildas vid en viss dos av de korsbindande ämnen vi undersöker. Vi kan även mäta hur fort ICLerna kan repareras i mänskliga celler med hjälp av metoden. Tack vare en kombination av våra mätningar och med hjälp av datorsimuleringar, kunde vi räkna ut hur många ICLs som bildades per dos för tre vanliga korsbindare. Vi kunde även visa att 50 % av ICLen har påbörjat reparationen och kommit så långt att de var bortklippta från ena stängen inom 3 timmar efter behandlingen. I artikel tre undersöker vi vilka proteiner som är inblandade i den tidiga delen av ICL reparationen, alltså fram till och med att celler klipper ut korsbindningen på båda sidorna om skadan i ena strängen. Här visar vi att celler som är defekta i reparationsprotein kallat XPA, har en betydligt långsammare borttagning av ICLer än vad båda normala celler och celler defekta i reparationsprotein XPE har. Vi visar även att detta inte påverkar cellens replikationshastighet, eller har någon effekt på cellens överlevnad. Den fjärde artikeln handlar om acetaldehyd, som bildas när alkohol förbränns i kroppen. Acetaldehyd har föreslagits bilda ICL och därför undersökte vi vilka effekter den har på cellerna. Vi visar i den här artikeln att det krävs nysyntes av DNA för att acetaldehyd ska leda till dubbelsträngsbrott. Celler kan reparera dessa dubbelsträngsbrott med hjälp av reparationssystem, som kallas homolog rekombination, men att reparationen ibland blir felaktig. I den femte och sista artikeln i avhandligen undersöker vi ett av de vanligast föreslagna proteinen för att sköta klippningen av DNA (ERCC1/XPF) och hur den är inblandad i reparationen av korsbindningar. Vi kan här visa att även det krosbindande ämnet mitomycin C bromsar replikationshastigheter och att ERCC1/XPF är nödvändigt för att kunna fullfölja homolog rekombination av ICLs. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Submitted. Paper 2: Manuscript. Paper 3: Manuscript. Paper 4: Submitted.</p>
6

Lipophiliebestimmung Kaliumkanal-blockierender Psoralenderivate mittels Flüssigchromatographie und Kapillarelektrophorese /

Carstens, Inga. January 2005 (has links)
Univ., Diss.--Kiel, 2005.
7

Estudo da eficácia, segurança e tolerabilidade do Brosimum gaudichaudii Trécul em indivíduos adultos portadores de vitiligo / Study of effectiveness, safety and tolerability of Brosimum gaudichaudii Trécul in adults vitiligo holders

Miranda, Amanda Rodrigues 03 December 2014 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2016-09-06T12:14:24Z No. of bitstreams: 2 Dissertação - Amanda Rodrigues Miranda - 2016.pdf: 3245490 bytes, checksum: 810f33abf110260d76f828e568843cfe (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-06T13:30:11Z (GMT) No. of bitstreams: 2 Dissertação - Amanda Rodrigues Miranda - 2016.pdf: 3245490 bytes, checksum: 810f33abf110260d76f828e568843cfe (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-09-06T13:30:11Z (GMT). No. of bitstreams: 2 Dissertação - Amanda Rodrigues Miranda - 2016.pdf: 3245490 bytes, checksum: 810f33abf110260d76f828e568843cfe (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2014-12-03 / Vitiligo is a chronic disease of skin, acquired and idiopathic, characterized by circumscribed depigmented macules or patches. The treatment is still a challenge and don´t have an effective treatment that may improve all patients. The traditional psoralen photosensitizers are options for the treatment of vitiligo. In the Brazilian cerrado is popularly known action of Brosimum gaudichaudii Trécul (BGT), or mamacadela, which is an herbal psoralen. The goal of this study was evaluate the efficacy, safety and tolerability of BGT in adult patients with vitiligo, in topical and systemic presentations. A randomized controlled trial, double-blind and placebo-controlled was conducted. Of the 58 selected patients, 33 were randomized, 17 in the treatment group (G1) and 16 in the placebo group (G2). These remained until the end of the study 10 patients in G1 and G2 in 6 patients. The interventions were 800 mg / day of medication per orally and use of the ointment for 22 weeks, together with graded and daily photoexposure. The effectiveness of the BGT was assessed using the Vitiligo Area Score Index (VASI), applied by a dermatologist at all clinic visits. Already the safety and tolerability were assessed by laboratory tests before and during treatment, and observation of adverse events. All patients were classified with generalized vitiligo. The group that received the medication (G1) improved significantly VASI in intra-group evaluation (p <0.05) and also a higher proportion of repigmentation compared to G2. The VASI don´t have association with the analysis variables (gender, age, skin type, previous treatment, education, emotional stress, time of diagnosis, treatment adherence) (p> 0.05). Adherence to photoexposure was irregular in both groups, and don´t have statistically significant relationship with changes of VASI (p > 0.05). Laboratory tests showed no significant changes. Adverse events were mild and transient and the most common being erythema, and occurred predominantly in G1 patients. Therefore, it can be concluded that the BGT is effective in the treatment of vitiligo, with safe and well tolerated in the long term. / O vitiligo é dermatose crônica adquirida, idiopática, que se manifesta por manchas acrômicas e bem delimitadas. Seu tratamento ainda é um desafio e não existe até o momento intervenção completamente eficaz. Os psoralenos são fotossensibilizantes tradicionais utilizados para o tratamento do vitiligo. No cerrado brasileiro é popularmente conhecida a ação da planta mamacadela (Brosimum gaudichaudii Trécul (BGT)) devido a presença de derivados psoralênicos em sua composição . O presente estudo teve como objetivo avaliar a eficácia, segurança e tolerabilidade de formulações farmacêuticas contendo extrato de raízes de BGT em pacientes adultos portadores de vitiligo, nas apresentações tópica e sistêmica. Foi realizado ensaio clínico randomizado, duplo-cego e placebo-controlado. Dos 58 pacientes selecionados, 33 foram randomizados, sendo 17 no grupo 1 (G1), de tratamento, e 16 no grupo 2 (G2), placebo. Destes, permaneceram até o final do estudo 10 pacientes no G1 e 6 pacientes no G2. Foram administrados 800 mg/dia da medicação, via oral, além da pomada, durante 22 semanas, associados a fotoexposição diária e gradativa. A eficácia do BGT foi avaliada através do Vitiligo Area Score Index (VASI), aplicado por dermatologista em todas as visitas clínicas. Já a segurança e tolerabilidade foram avaliadas pela realização de exames laboratoriais, antes e durante o tratamento, além da observação de eventos adversos. Todos os pacientes foram classificados com vitiligo generalizado. O grupo que recebeu a medicação (G1) apresentou melhora significativa do VASI na avaliação intragrupos (p<0,05) e também maior proporção de repigmentação quando comparado ao G2. O VASI não demonstrou associação com as variáveis de análise (sexo, idade, fototipo, tratamento prévio, escolaridade, estresse emocional, tempo de diagnóstico, adesão ao tratamento) (p>0,05). A adesão à fotoexposição foi irregular em ambos os grupos e não apresentou relação estatisticamente significante com as alterações do VASI (p>0,05). Em consonância, os exames laboratoriais não apresentaram alterações significativas. Os eventos adversos foram leves e transitórios, sendo mais comum o eritema, e ocorreram predominantemente nos pacientes do G1. Portanto, pode-se concluir que o BGT é eficaz no tratamento do vitiligo, sendo seguro e bem tolerado a longo prazo.
8

Identification moléculaire et caractérisation fonctionnelle d'une nouvelle sous-famille de cytochromes P450, CYP71AZ, impliquée dans la synthèse de furanocoumarines et coumarines chez Pastinaca sativa / Molecular isolation and functional characterization of a novel cytochrome P450 subfamily, CYP71AZ, involved in the biosynthesis of furanocoumarins and coumarins in Pastinaca sativa

Krieger, Célia 16 December 2014 (has links)
Les furanocoumarines (FCs) sont des métabolites secondaires principalement synthétisés chez quatre familles botaniques et dérivent de la voie de biosynthèse des phénylpropanoïdes. Ces phytoalexines interviennent dans les processus de défense de la plante et présentent un fort potentiel thérapeutique. Des travaux réalisés dans les années 1960 sur des cultures cellulaires en parallèle de l’utilisation de précurseurs radiomarqués ont permis de démontrer que de nombreuses enzymes impliquées dans cette voie appartenaient à la famille des cytochromes P450 (P450s). Seules deux d’entre elles avaient pu être identifiées d’un point de vue moléculaire au début de ce travail de thèse. Afin de générer des informations concernant le génome de plantes productrices de FCs, nous avons fait séquencer les ARNm extraits de feuilles de Pastinaca sativa, de Ruta graveolens et de Cullen cinereum. L’analyse in silico de ces trois banques de données a permis d’identifier près de 800 fragments d’ADNc codants pour des P450s. Des travaux antérieurs réalisés au laboratoire et l’analyse comparative des transcriptomes de ces 3 plantes nous ont amenés à nous focaliser sur la sous-famille CYP71AZ au travers d’une étude fine de CYP71AZ3 et CYP71AZ4. La caractérisation fonctionnelle de ces enzymes a été réalisée dans un système d’expression hétérologue eucaryote : Saccharomyces cerevisiae. Les résultats obtenus ont permis de montrer que CYP71AZ4 avait une spécificité de substrat assez large puisqu’elle pouvait métaboliser au moins une FC et 4 coumarines. L’analyse et la comparaison des constantes cinétiques pour chacun de ces substrats indiquent néanmoins que le psoralène est le substrat préférentiel. La caractérisation fonctionnelle de CYP71AZ3 a mis en évidence que cette enzyme pouvait hydroxyler l’esculétine, une coumarine, mais ne jouait aucun rôle dans la synthèse de FCs. Ces travaux mettent en évidence la diversité fonctionnelle au sein d’une même sous-famille enzymatique et permettent d’émettre des hypothèses nouvelles quant à l’apparition de cette voie de biosynthèse chez les Apiacées d’une part, et chez les autres familles botaniques d’autre part / Furanocoumarins (FCs) are secondary metabolites mainly synthetized in four botanical families deriving from the phenylpropanoid biosynthetic pathway. These phytoalexins are involved in plant defense mechanisms and present strong therapeutic potential. Early studies in the 1960s based on cell cultures and the use of radiolabeled precursors have shown that many enzymes involved in this pathway belong to the cytochrome P450 family (P450s). Only two of them had been identified from a molecular point of view at the beginning of this thesis. In order to generate information regarding the genome of plants producing FCs, we sequenced the mRNA extracted from leaves of Pastinaca sativa, Ruta graveolens, and Cullen cinereum. In silico analysis of these three libraries identified nearly 800 cDNA fragments encoding for P450s. Previous studies in the laboratory and comparative transcriptome analysis of these three plants have led us to focus on the subfamily CYP71AZ through a detailed study of CYP71AZ3 and CYP71AZ4. Functional characterization of these enzymes was performed in an eukaryote heterologous expression system: Saccharomyces cerevisiae. The results showed that CYP71AZ4 had a broad substrate specificity enough as it could metabolize one FC and 4 coumarins. The analysis and comparison of the kinetic constants for each of these substrates indicate, however, that the preferred substrate is psoralen. The functional characterization of CYP71AZ3 showed that this enzyme could hydroxylate esculetin, a coumarin, but played no role in the synthesis of FCs. This study highlights the functional diversity within a single enzyme subfamily and allows to issue new hypotheses about the emergence of this biosynthetic pathway in Apiaceae on one hand, and among other botanical families on the other hand
9

Optimalizace chromozómových manipulací u jeseterovitých ryb

LEBEDA, Ievgen January 2014 (has links)
Highly profitable black caviar market and the depletion of wild sturgeon stocks warrant improvements in sturgeon aquaculture. Therefore, chromosomal manipulations, particularly gynogenesis, are focused on for increasing the ratio of females over males in progeny. The present study focused on optimizing chromosomal manipulations in sturgeons, particularly gynogenesis. The reasons of low survival rates were analyzed and the critical steps of gynogenesis induction processes were optimized. In addition, alternative ways of DNA inactivation in sperms were investigated, as well as the influence of native light-dependent DNA repair mechanisms on gynogenesis induction. Methods of interspecific gynogenesis usage for simplifying gynogenetic progeny separation were also proposed. Spectrophotometry analysis was used to investigate the ability of UV light, as the most common DNA inactivating agent, to penetrate into sperm. In addition, investigation of UV-irradiated sperm motility and results of partial gynogenesis induction showed that low transparency of sperms for UV-light can cause significant heterogeneity of UV-irradiation. As a result, a proper dilution of sperm was suggested as a critical step for homogeneous UV-irradiation of samples. Gynogenesis in sterlet was induced with chemical agents that damage sperm DNA, as an alternative to UV irradiation for applied in large-scale production of gynogenotes. All tested substances showed ability to inactivate DNA in spermatozoa, and thus producing gynogenotes. Negative impact of treatments with chemical agents on the sperm motility was observed. Subsequently, these treatments had a low efficiency of gynogenesis induction. The highest percentage of produced gynogenetic larvae 19.8 ? 8.9% was obtained by treatment with aminomethyl-4,5?,8-trimethylpsoralen (AMT) at 50 ?M followed by UV-A (360 nm) irradiation at dose of 900 J/m2. Therefore, this treatment could be used as a substitute for commonly used UV-C irradiation, e.g., in the case of large volumes of sperm. Detailed investigation of photoreactivation in sturgeon sperm revealed a significant level of light-dependent DNA restoration in sperms irradiated with high doses of UV-C light. Induction of gynogenesis with UV-C irradiation followed by exposure to visible light resulted in significant deviations from the typical Hertwig effect. In contrast, the red light with a wavelength of more than 600 nm did not result in decreased DNA damage, instead a moderate increase in damage was observed, i.e., it did not induce photoreactivation. Therefore, the use of infrared light to illuminate work stations during the induction of gynogenesis is suggested. The use of interspecific gynogenesis, particularly gametes of sturgeon species with different ploidy levels, was suggested as a way to simplify the separation of gynogenotes. In addition, application of this method allowed studying the effectiveness of DNA-inactivation and ploidy restoration treatments separately, as well as evaluation of fitness parameters and survival rates in each group of progeny without the physical separation of fish. Finally, the protocol for tetraploidization in sterlet was optimized for the prospective using tetraploid individuals for the induction of gynogenesis and androgenesis with diploid eggs and sperm. In conclusion, the described methods and protocols allowed gynogenesis induction in sturgeons with a survival rate sufficient for aquaculture, taking into consideration their high fertility, although further studies of the consequences of this treatment on fish is required.
10

Obtenção de pellets a partir dos extratos líquidos padronizados de Brosimum gaudichaudii Trécul (Moraceae) ou Lafoensia pacari A. St.-Hil. (Lythraceae) / Production of pellets from the liquid extracts standardized Brosimum gaudichaudii Trécul (Moraceae) or Lafoensia pacari A. St. Hil. (Lythraceae)

Silva Filho, Omar Paulino 11 July 2014 (has links)
Submitted by JÚLIO HEBER SILVA (julioheber@yahoo.com.br) on 2017-06-13T20:14:26Z No. of bitstreams: 2 Dissertação - Omar Paulino da Silva Filho - 2014.pdf: 773195 bytes, checksum: 68a3f309ec2cd70a400359919399ad6b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-06-14T15:25:01Z (GMT) No. of bitstreams: 2 Dissertação - Omar Paulino da Silva Filho - 2014.pdf: 773195 bytes, checksum: 68a3f309ec2cd70a400359919399ad6b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-06-14T15:25:02Z (GMT). No. of bitstreams: 2 Dissertação - Omar Paulino da Silva Filho - 2014.pdf: 773195 bytes, checksum: 68a3f309ec2cd70a400359919399ad6b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2014-07-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Pellets are spherical solid oral dosage forms that can be used in the development of new pharmaceutical products with standardized plant extracts. Brosimum gaudichaudii Trécul (Moraceae) and Lafoensia pacari A. St.-Hil. (Lythraceae) are typical species from the Cerrado biome. The extract obtained from the roots of B. gaudichaudii is traditionally used in the treatment of vitiligo, its effectiveness is due to the presence of the chemical markers psoralen and bergapten. As for L. pacari, the barks of the branches and trunk are traditionally used in the treatment of gastric ulcers, highly valued for there anti-inflammatory and wound healing because of there ellagic acid content. For each of these species optimal extractive methods exist to obtain standardized liquid extracts. However there are no studies that propose the development of solid oral dosage forms from them. Thus, the present study is aimed at obtaining pellets from the standardized liquid extract of the B. gaudichaudii roots, furthermore to determine the efficiency of a photoprotector coating on the stability of psoralen and bergapten and also obtaining pellets with standardized liquid extract of the L. pacari barks from the branches and trunk. The B. gaudichaudii roots were collected in the city of Jussara, Goiás, and the L. pacari barks in Niquelândia, Goiás. Separately, the raw materials were cleaned, dried in an oven with forced air circulation, then subsequently milled for the extractive process. After the standard liquid extract of B. gaudichaudii had been obtained, six formulas were developed at bench scale. Among these, one stood out by the homogeneity of the lot and the sphericity of its pellets. This formula had been selected to be sacaled-up and it`s composition had been formed by 49.5% (w/w) of microcrystalline cellulose (MCC), 1% (w/w) of hydroxypropylmethyl cellulose (HPMC) and 49.5% (w/w) of that extract. The pellets obtained from the scaled formula were divided into two portions, one of them had been coated with a photoprotective layer and both were subjected to a photostability test. The degradation of the markers had been evident only in the uncoated pellets. The reduction of 1.87% (w/w) in the content of psoralen and 8.1% (w/w) in bergapten content had been observed after 3 J/cm2 exposure to UVB radiation. After exposing to 30 J/cm2 of UVA, there had been a reduction of 24.1% (w/w) of psoralen and 28.48% (w/w) of bergapten. Therefore, the application of the photoprotective coating had been an effective alternative and ensured the stability of the chemical markers after the test. With respect to the liquid extract of L. pacari, 13 formulas were obtained among which only two formed pellets whose batch homogeneity had been greater than 70%. Among them, only one had been chosen to obtain the first scaled-up model. With the production of the scaled-up batch, it had been observed that formulas prepared with a lower proportion of standardized liquid extract of L. pacari had enabled us to obtaing more homogeneous, spherical and a smoother pellets. Based on these results and due to the innovative character of the studies, this work can be used as a model for future trials designed to obtain pellets with standardized liquid extract of B. gaudichaudii or L. pacari. / Pellets são formas farmacêuticas sólidas orais esféricas que podem ser utilizadas no desenvolvimento de novos produtos farmacêuticos a partir de extratos vegetais padronizados. Brosimum gaudichaudii Trécul (Moraceae) e Lafoensia pacari A. St.-Hil. (Lythraceae) são espécies típicas do bioma Cerrado. O extrato obtido das raízes de B. gaudichaudii é utilizado tradicionalmente no tratamento de vitiligo, cuja eficácia se deve pela presença dos marcadores químicos psoraleno e bergapteno. Quanto à espécie L. pacari, são tradicionalmente utilizados as cascas dos galhos e do tronco no tratamento de úlceras gástricas, cuja ação anti-inflamatória e cicatrizante é atribuída ao ácido elágico. Para cada uma destas espécies existem métodos extrativos otimizados para obtenção de extratos líquidos padronizados nos respectivos marcadores químicos. No entanto, não há estudos que proponham o desenvolvimento de formas farmacêuticas sólida orais a partir destes. Assim, o presente trabalho teve como objetivo obter pellets a partir do extrato hidroalcoólico das raízes de Brosimum gaudichaudii, padronizado em psoraleno e bergapteno, determinar a eficácia do revestimento fotoprotetor na estabilidade do psoraleno e bergapteno, além de obter pellets com o extrato hidroalcoólico das cascas dos galhos e do tronco de Lafoensia pacari, padronizado em ácido elágico. As raízes de B. gaudichaudii foram coletadas no município de Jussara, Goiás, e as cascas dos galhos e do tronco de L. pacari em Niquelândia, Goiás. Separadamente, as matérias-primas vegetais foram limpas, secas em estufa com circulação forçada de ar, posteriormente trituradas para a obtenção dos respectivos extratos líquidos padronizados. A partir do extrato líquido padronizado de B. gaudichaudii, foram obtidas seis fórmulas em escala de bancada. Dentre estas, uma se destacou pela homogeneidade do lote e pela esfericidade dos pellets. Deste modo, a fórmula que se destacou foi selecionada e escalonada, sua composição é formada pela mistura de XX% (m/m) de celulose microcristalina (CMC), X% (m/m) de hidroxipropilmetilcelulose (HPMC) e 49,5% deste extrato. Os pellets obtidos a partir da fórmula escalonada foram divididos em duas partes, em uma foi aplicado o revestimento fotoprotetor e ambas foram submetidas ao ensaio de fotoestabilidade. Desse modo, a degradação dos marcadores foi evidente apenas nos pellets sem o revestimento, cuja redução de no teor de psoraleno e bergapteno foi igual a 1,87% (m/m) e 8,1% (m/m), após a exposição a 3 J/cm2 de radiação UVB. Após a exposição a 30 J/cm2 de UVA, houve a redução de 24,1% (m/m) de psoraleno e 28,48% (m/m) de bergapteno. Portanto, a aplicação do revestimento fotoprotetor foi uma alternativa eficaz e garantiu a estabilidade dos marcadores químicos após o ensaio. Com relação ao extrato líquido de L. pacari, foram obtidas 13 fórmulas, dentre as quais apenas duas formaram pellets cuja homogeneidade dos lotes foi superior a 70% e apenas uma foi escolhida como modelo para a obtenção do lote piloto. Com a produção do lote piloto foi observado que fórmulas elaboradas com menor proporção do extrato padronizado de L. pacari e a mecanização do processo de mistura dos componentes da fórmula, possibilitam a obtenção de pellets mais esféricos, homogêneos e com superfície menos irregular. Diante dos resultados obtidos e devido ao caráter inovador dos estudos realizados, este trabalho pode ser utilizado como modelo para ensaios futuros destinados a obtenção de pellets com o extrato líquido padronizado de B. gaudichaudii ou L. pacari.

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