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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.
591

Extratos de Coccoloba alnifolia Casar e suas atividades biol?gicas

Melo, Luciana Fentanes Moura de 08 March 2018 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-04-02T15:02:43Z No. of bitstreams: 1 LucianaFentanesMouraDeMelo_DISSERT.pdf: 1510669 bytes, checksum: f402172547ca541fafef3500e5ce47a8 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-04-05T14:12:02Z (GMT) No. of bitstreams: 1 LucianaFentanesMouraDeMelo_DISSERT.pdf: 1510669 bytes, checksum: f402172547ca541fafef3500e5ce47a8 (MD5) / Made available in DSpace on 2018-04-05T14:12:02Z (GMT). No. of bitstreams: 1 LucianaFentanesMouraDeMelo_DISSERT.pdf: 1510669 bytes, checksum: f402172547ca541fafef3500e5ce47a8 (MD5) Previous issue date: 2018-03-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O uso de plantas medicinais ? uma pr?tica comum da humanidade desde a antiguidade. Tal conhecimento baseado na experi?ncia tem sido repassado por muitas comunidades e grupos ?tnicos, e serve como ponto de partida para estudos bioqu?micos e farmacol?gicos dos princ?pios ativos presentes nas plantas. Para isto, neste trabalho foram avaliados o potencial antioxidante e tamb?m biol?gico, utilizando sistemas in vitro e in vivo dos diferentes extratos obtidos de folhas da planta Coccoloba alnifolia. Foram obtidos inicialmente seis extratos: hexano (EH), clorof?rmio (EC), etan?lico (EE), metan?lico (EM), ?gua final (EAF) e aquoso (EA) a partir das folhas frescas da planta. Posteriormente, foram avaliados o teor de a??car, prote?nas e compostos fen?licos. Os resultados obtidos na triagem fitoqu?mica sugerem a presen?a de fen?is, flavonoides, saponinas, n?cleo triterp?nicos e esteroidais e n?cleo esteroidal insaturado, j? com a metodologia de cromatografia em camada delgada (CCD), foi observado uma abund?ncia de flavonoides. Foram realizados quatro ensaios: Teste do Poder Redutor, Quela??o de ?ons Metais, Quela??o de Cobre e Atividade Sequestradora de Radical Hidroxila. Estes ensaios permitiram verificar que os extratos apresentaram atividade antioxidante nas concentra??es avaliadas de 100, 250 e 500 ?g/mL. Foi verificado principalmente para os extratos EE, EM e EA as atividades antioxidante nos ensaios poder redutor e sequestro do radical hidroxila. A correla??o de Pearson mostrou que estes dados est?o associados aos compostos fen?licos e a??cares. E com o modelo das linhagens celulares foi observado que a maioria dos extratos avaliados neste trabalho n?o mostrou-se citot?xico para as linhagens celulares. Os extratos tamb?m n?o inibiram o crescimento da levedura Candida parapsilosis. Os extratos obtidos da folha de C. alnifolia apresenta um potencial antioxidante interessante, e os resultados obtidos tanto nos modelos in vitro, como as linhagens celulares, refor?am que s?o necess?rios mais estudos para compreender o potencial destes extratos in vivo e identificar quais s?o as biomol?culas associadas com estas atividades e seus respectivos potenciais biotecnol?gicos. / The use of medicinal plants has been a common practice in folk medicine. This knowledge has been based on the experience that it has been passed though many generations. However, many times this knowledge do not have any scientific base. The molecules responsive for these activities are the secondary metabolic produce as a response to environmental conditions (biotic or abiotic stress). The Mata atl?ntica biome has a rich flora, which needs to be studied for its biological activities, and its potential to identify new biomolecules. In order to do this, six extracts (HE, CE, EE, ME, WEE e WE) were obtained from Coccoloba alnifolia leaves and then it was evaluated the antioxidant and the biological potential using different in vitro and in vivo systems. First, it was measured the sugar content, proteins and phenolic compounds. Based on these results, qualitative experiments were carried out to determine the secondary metabolites present in these extracts. It was detected the presence of phenols, flavonoids, saponins, triterpenic, and steroidal nuclei and unsaturated steroidal nuclei. After that, it was evaluated the antioxidant potential by four in vitro assay: Redution Power test, Metal Ion Chelation, Copper Chelation and Hydroxyl Radical Scavenging Activity. These assays allowed us verify that the extracts presented antioxidant activity at extract concentrations: 100, 250 and 500 ?g/mL. It was observed the ethanolic, methanolic and aqueous extracts had activity in reducing power and scavenging of the hydroxyl radical. The Pearson?s correlation showed that these results may be associated to the presence of phenolic compounds and sugars. The third in vitro model used in this work was cell culture. When it was used the 3T3 lineage it was observed that these extracts were not cytotoxic. However, it was not observed any antiproliferative activity in tumor cell lineages. In sumary, the data obtained here showed that using in vitro assays that these extracts in special ethanolic and aqueous had an interesting antioxidant potential and it will be important to go further in this research.
592

Acetilcolinesterase, butirilcolinesterase, carboxilesterase e a resistência de peixes neotropicais aos pesticidas organofosforados / Acetylcholinesterase, butyrylcholinesterase, carboxylesterase and the resistenance of neotropical fishes to organophosphorus pesticides

Aline Simões Fraga 04 March 2010 (has links)
Todos os agrupamentos humanos que se organizam para o trabalho usam rios, lagos ou lagoas como depósitos para a decomposição de matéria indesejável. A contaminação do meio aquático por herbicidas e agrotóxicos derivados de práticas agrícolas se tornou, faz tempo, um problema de importância mundial. Precisamos de informações detalhadas sobre a bioquímica da intoxicação de peixes nativos para avaliarmos quais os efeitos de agrotóxicos sobre os processos bioquímicos que mantêm o ciclo de vida dos peixes em águas do Brasil. Organofosfatos, que são agrotóxicos de uso disseminado, podem interagir com as B-esterases butirilcolinesterase (EC 3.1.1.8) e carboxilesterase (EC 3.1.1.1) presentes no fígado e no plasma. Tanto a butirilcolinesterase (BChE) como a carboxilesterase (CarbE), se presentes em concentrações relativamente elevadas, agem como limpadores estequiométricos (scavengers moleculares) por ligarem o átomo de fósforo do grupo P=O com a hidroxila de uma serina presente nos seus sítios ativos. Em nossos resultados observamos que curimbatá possui a CarbE plasmática (IC50 74 ηM) mais sensível ao organofosfato metilparaoxon quando comparado ao pacu (IC50 691 ηM). Isolamos CarbE dos plasmas de curimbatá e pacu. Piavussu não possui uma atividade expressiva de CarbE no sangue, por isso não a isolamos. O tipo e a distribuição das esterases nos tecidos são particulares da espécie. Curimbatá tem alta atividade de CarbE no fígado (237,8 U.g-1) e no sangue (29,85 U.mL-1), pacu é dotado de alta atividade de BChE (134,0 U.g-1) e CarbE (149,6 U.g-1) no fígado, mas o piavussu conta apenas com a BChE do sangue (17,87 U.g-1). Este arsenal enzimático foi suficiente para proteger as AChE de cérebro, músculo e coração das três espécies e evitar a sua intoxicação leve por 0,2 mg metilparation/L. A abordagem cinético-bioquímica para conhecer a inibição das esterases presentes nos tecidos de diferentes espécies de peixes por / Every human group who organizes to work together uses rivers, lakes or ponds as places in which undesirable substances are deposited for decomposition. Contamination of the aquatic environment with herbicides and pesticides derived from agricultural practices has become a problem of global importance since a long ago. We need detailed information on the biochemistry of the poisoning of native fish to assess the effects of pesticides on the biochemical processes that maintain fishes life cycle in waters of Brazil. Organophosphates, which are widely used pesticides, can interact with the B-esterases butyrylcholinesterase (EC 3.1.1.8) and carboxylesterase (EC 3.1.1.1) in plasma and liver. Butyrylcholinesterase (BChE) and carboxylesterase (CarbE) in relatively high concentrations act as stoichiometric scavengers by linking the phosphorus atom of the P=O group with the serines hydroxyl they have in their active site. Our results show that the CarbE of curimbata plasma (IC50 74 ηm) is more sensitive to the organophosphate metilparaoxon than CarbE of pacu plasma (IC50 691 ηm). We isolated CarbE from curimbata and pacus plasma. Piavussu does not have an expressive activity of CarbE in plasma, so we did not isolate it. The type and distribution of esterases in tissues are peculiar to a species. Curimbata has high CarbE activity in the liver (237.8 U.g-1) and blood (29.85 U.mL-1), pacu is equipped with high activities of BChE (134.0 U.g-1) and CarbE (149.6 U.g-1) in the liver and piavussu relies only on BChE of blood (17.87 U.g-1). This enzymatic arsenal was sufficient to protect AChE from brain, muscle and heart of the three species and protect them against mild intoxication by methylparathion (0.2 mg / L). The biochemical kinetic approach that allows understanding of the inhibition of the esterases in tissues of different fish species is a good tool capable of anticipating the harmful consequences of these drugs.
593

Efeito da restrição protéica materna durante a lactação sobre a resposta de timócitos da prole jovem de ratos Wistar / Maternal protein deprivation during lactation increases leptin activity and inhibits apoptosis of thymic cells from young offspring

Carolina Salama Rodrigues 16 March 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste estudo investigamos as consequências da restrição protéica materna durante a lactação sobre a resposta de timócitos da prole jovem de ratos Wistar (grupo D), identificando o papel da leptina nas alterações encontradas. Observamos que, quando comparados ao grupo controle, os animais do grupo D apresentaram, aos 30 dias de vida, uma diminuição significativa tanto do peso corporal quanto do timo. Contudo, não observamos alterações no número de timócitos, no perfil de células CD4/CD8 ou na resposta proliferativa destas células. Sistemicamente, o grupo D não apresentou alterações nos níveis séricos de corticosterona ou no conteúdo nuclear do seu receptor (GR) em timócitos. Apesar dos animais D não apresentarem alterações nos níveis circulantes de leptina, a expressão do seu receptor, ObRb, estava aumentada nos timócitos. Esta alteração foi acompanhada pela amplificação da resposta de sinalização da leptina nestas células, observada por um aumento na ativação de JAK2 e STAT3 após a incubação com leptina. Os timócitos isolados do grupo D apresentaram uma diminuição significativa na taxa de apoptose espontânea quando comparados ao grupo controle. Corroborando estes resultados, demonstramos que os timócitos dos animais D apresentam um aumento na expressão da proteína antiapoptótica Bcl-2 e uma redução da expressão da proteína próapoptótica Bax, além de um maior conteúdo de Pró-caspase-3, entretanto, não encontramos alterações no conteúdo de Bad. Além disso, timócitos do grupo D apresentaram um maior conteúdo da subunidade p65 do NFĸB no núcleo, associado a uma menor expressão de IĸBα no citoplasma. Finalmente, observamos um aumento na expressão do RNAm para o gene ob (leptina) mas não para o gene db (receptor) no microambiente tímico dos animais D. Em conjunto, nossos dados mostram que a restrição protéica durante a lactação afeta a homeostase tímica, induzindo uma maior atividade de leptina, que protege os timócitos da apoptose na prole jovem, sugerindo que esses animais poderiam ser mais suscetíveis a alterações na resposta imune na vida aduta. / In this study, we investigated the consequences of maternal protein deprivation during lactation on thymocyte responses of the offspring Wistar rats (PD group) and the role of leptin in these alterations. Compared to group C, PD animals showed at 30 days of age, lower body and thymus weights, with no alteration in the thymocyte number or any difference in the profile of T cell subsets, or in their proliferative response. Similar circulating levels of corticosterone and GR nuclear contents were detected in thymic cells of PD or control groups. In contrast, despite the rats from PD group did not present alterations in leptin circulating levels, the expression of leptin receptor ObRb was enhanced in their thymocytes. This change was accompanied by an amplification in leptin signaling response of thymocytes from PD rats, which showed an increase in JAK2 and STAT3 phosphorylation after stimulation with leptin. Moreover, the thymic cells from PD rats presented a decreased rate of spontaneous apoptosis when compared to controls. Accordingly, higher expression of both the anti-apoptotic protein Bcl-2 and Procaspase-3 and lower expression of pro-apoptotic protein Bax were detected in PD thymocytes, however, the pro-apoptotic protein bad expression was similar between the groups. Thymocytes from PD group also exhibited a constitutive higher nuclear content of p65 NFkB associated to a lower IkB content in the cytoplasm. Finally, although there was no change in db genic (leptin receptor) expression in PD thymocytes, a higher expression of mRNA for ob gene (leptin) was observed in the thymic microenvironment from PD animals. Taken together, the results show that maternal protein deprivation during lactation affects thymic homeostasis, inducing leptin activity, which protect thymocytes from apoptosis in young progeny and, perhaps,may prone these animals for alterations in immune response in adult life.
594

Obten??o e avalia??o do potencial imunoadjuvante de nanopart?culas de quitosana na produ??o de antissonoros contra venenos de serpentes e escorpi?es

Soares, Karla Samara Rocha 31 May 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-10T15:32:21Z No. of bitstreams: 1 KarlaSamaraRochaSoares_TESE.pdf: 2883085 bytes, checksum: 02667bee72d9ca986a7f49f759803663 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-11T15:56:53Z (GMT) No. of bitstreams: 1 KarlaSamaraRochaSoares_TESE.pdf: 2883085 bytes, checksum: 02667bee72d9ca986a7f49f759803663 (MD5) / Made available in DSpace on 2017-01-11T15:56:53Z (GMT). No. of bitstreams: 1 KarlaSamaraRochaSoares_TESE.pdf: 2883085 bytes, checksum: 02667bee72d9ca986a7f49f759803663 (MD5) Previous issue date: 2016-05-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Acidentes com animais pe?onhentos representam um s?rio problema de sa?de p?blica em diversos pa?ses, destacando-se os acidentes of?dicos e escorpi?nicos. No Brasil, as serpentes do g?nero Bothrops e os escorpi?es pertencentes ao g?nero Tityus, s?o as de maior relev?ncia cl?nica. O tratamento para o envenenamento consiste em administra??o de soros antiof?dico e antiescorpi?nico. Vacinas que utilizam ant?genos puros e vias de administra??o alternativa requerem o uso de adjuvantes potentes e um sistema de entrega de ant?geno eficaz. Nanossistemas v?m sendo investigados como sistemas de libera??o para macromol?culas terap?uticas. A quitosana, devido as suas propriedades, tem sido extensivamente investigada na formula??o de nanocarreadores, particularmente de genes e prote?nas. Este estudo teve como objetivo a obten??o de nanopart?culas de quitosana (CNP) com base na gelifica??o i?nica para carrear prote?nas/pept?deos terap?uticos utilizados na imunoterapia e avalia??o do potencial imunoadjuvante dessas nanopart?culas na produ??o de soros antivenenos. CNP foram obtidas por gelifica??o i?nica, com tamanho m?dio de 160 nm, caracterizadas f?sico-quimicamente e o perfil de libera??o avaliado, demonstrando se tratar de um sistema de libera??o modificado. A estabilidade dos sistemas foi avaliada por 7 semanas, observando-se uma maior estabilidade dos sistemas associados aos venenos. Animais experimentais foram imunizados durante 6 semanas com 100 ?L de veneno das serpentes atrav?s inje??es subcut?neas, em diferentes concentra??es (5,0 ou 10,0%), encapsuladas em CNP ou associados ao hidr?xido de alum?nio (HA). Os resultados demonstram que os t?tulos de anticorpos obtidos para os animais vacinados com os nanossistemas foram equivalentes ou maiores aos obtidos para os animais vacinados com o HA, com a vantagem desses serem menos inflamat?rios que o HA, exigindo uma menor quantidade de ant?geno a ser administrada, por se tratar de um sistema de liberta??o modificada, revelando a obten??o de um novo sistema nanoparticulado com potencial aplica??o na soroterapia. / Accidents with venomous animals represent a serious public health problem in many countries of the world, with emphasis to snake and scorpion accidents. In Brazil, Bothrops snakes are the most clinically relevant. Regarding scorpions, the genus Tityus includes the species of higher medical importance. Treatment for envenomation consists mainly in the administration of antivenom sera. Vaccines using pure antigens in alternative administration routes require the use of potent adjuvants and an effective antigen delivery system. Nanosystems are being investigated as delivery systems for therapeutic macromolecules. Chitosan, due to its properties, has been extensively investigated in nanocarriers formulations, particularly for genes and proteins. This study aimed to obtain chitosan nanoparticles (CNP) based on ionic gelation for the delivery of therapeutic proteins/peptides used in immunotherapy, as well as to evaluate the immunoadjuvant potential of these nanoparticles in the production of antivenom serums. CNP were obtained by ionic gelation, with an average size of 160 nm. Physicochemical characterization and evaluation of the release profile demonstrated that it is a modified release system. The stability of different systems was evaluated for 7 weeks, observing a greater stability of the systems associated with venoms. Experimental animals were immunized subcutaneously for 6 weeks with 100 uL snake venoms at different concentrations (5.0 or 10.0%), either encapsulated in CNP or associated with aluminum hydroxide (AH). The results demonstrate that the antibody titers observed for animals vaccinated with the studied nanosystems were equivalent or higher than those observed for animals vaccinated with HA. Further advantages of the nanosystems were to be less inflammatory, and to require smaller amounts of antigen to be administered, because it is a modified-release system, with potential application in anti-venom serum therapy.
595

Atividade antiviral de extratos brutos, ricos em polissacar?deos sulfatados, obtidos de macroalgas marrons e verdes contra o v?rus dengue 2

Bezerra, Fabiana Lima 14 June 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-27T13:32:41Z No. of bitstreams: 1 FabianaLimaBezerra_TESE.pdf: 4985146 bytes, checksum: ce1c1005e6775f052912c875b1d39910 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-31T13:32:42Z (GMT) No. of bitstreams: 1 FabianaLimaBezerra_TESE.pdf: 4985146 bytes, checksum: ce1c1005e6775f052912c875b1d39910 (MD5) / Made available in DSpace on 2017-01-31T13:32:42Z (GMT). No. of bitstreams: 1 FabianaLimaBezerra_TESE.pdf: 4985146 bytes, checksum: ce1c1005e6775f052912c875b1d39910 (MD5) Previous issue date: 2016-06-14 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A dengue ? a mais importante arbovirose que afeta o homem e constitui-se em um grave problema de sa?de p?blica. A doen?a ? end?mica em regi?es tropicais e subtropicais, abrangendo mais de 100 pa?ses, correspondendo ? metade da popula??o mundial. As epidemias s?o recorrentes e estima-se que os v?rus da dengue causem 390 milh?es de infec??es a cada ano, sendo uma importante causa de morbidade. Apesar desse cen?rio, atualmente, ainda n?o se disp?e de um antiviral contra a dengue. Neste contexto, diversos estudos relatam a atividade antiviral dos polissacar?deos sulfatados obtidos das algas marinhas contra v?rus envelopados, cuja a??o est? associada ? interfer?ncia nas etapas iniciais do processo de infec??o viral. Neste estudo, avaliou-se a potencial atividade antiviral de extratos brutos ricos em polissacar?deos sulfatados obtidos das algas marrons Dictyota menstrualis (EBDMens) e Dictyota mertensii (EBDM) e das algas verdes Codium isthmocladum (EBCI) e Caulerpa sertularioides (EBCS) contra o v?rus dengue 2 (DENV-2), em linhagem de c?lulas Vero, usando diferentes estrat?gias metodol?gicas (tratamento simult?neo, tratamento p?s-infec??o, pr?-tratamento da c?lula, pr?tratamento do v?rus, adsor??o, p?s-adsor??o e penetra??o). A citotoxicidade dos extratos foi analisada pelo ensaio de redu??o do MTT. O estudo da atividade antiviral foi determinado pela quantifica??o do n?mero de c?pias do RNA viral por RT-qPCR ap?s 120 h de infec??o. Nenhum extrato exibiu toxicidade para as c?lulas Vero no ensaio de redu??o do MTT na concentra??o de 100 ?g/mL. Todos os extratos exibiram atividade antiviral quando adicionados durante os primeiros 90 minutos de infec??o, demonstrando redu??o significativa no n?mero de c?pias do RNA viral ap?s 120 horas. Os extratos EBDMens e EBDM foram mais eficazes nos ensaios de pr?-tratamento da c?lula e do v?rus, e o primeiro exerceu atividade antiviral superior ao EBDM durante a adsor??o viral. Os extratos EBCI e EBCS apresentaram atividade antiviral semelhante no ensaio de pr?-tratamento da c?lula. O EBCI foi mais eficaz na redu??o da adsor??o do DENV-2 em c?lulas Vero. Por?m, o EBCS se mostrou mais eficiente nos ensaios de pr?-tratamento do v?rus e penetra??o. Dentre os extratos avaliados, o EBCS parece ser o mais efetivo no combate ao DENV-2. Estes resultados revelam o potencial desses extratos ricos em polissacar?deos sulfatados como compostos com a??o antiviral, sugerindo que eles atuam nos est?gios iniciais da infec??o por DENV-2. / Dengue is considered the most important human arboviruses, and is a serious public health problem. This disease is endemic in tropical and subtropical regions, reaching more than 100 countries, which means the half of world population, and those epidemies have been appellant. It is estimated that Dengue virus could cause 390 millions of infections each year, and is an important cause of morbidity. Although this scenario, actually doesn?t exist a dengue antivirals still. Sorts of studies have showed antivirus activity of seaweed sulfated polysaccharides against enveloped viruses, which action seems to be associated to initials steps of infection process. In this study, was evaluated the potential antiviral activity of crude extracts rich in sulfated polysaccharides obtained from the brown algae Dyctiota menstrualis (EBDMens) and Dyctiota mertensii (EBDM), and green algae Codium isthmocladium (EBCl) and Caulerpa sertularioides (EBCS), tested against Dengue virus 2 (DENV-2) in Vero cell line, by using different methodological strategies (simultaneous treatment, post-infection treatment, cell pre-treatment, virus pre-treatment, adsorption, post-adsorption and penetration). The extracts cytotoxicity was evaluated by MTT reduction assay. The study of antiviral activity was determinated by quantifying viral RNA load using RT-qPCR, after 120 hours of infection. None extract has showed toxicity against Vero Cells in MTT reduction assay with 100 ?g/mL concentration. All extracts have shown antiviral activity when added during the first 90 minutes of infection, and a significant reduction of viral RNA number of copies after 120 hours. The EBDMens and EBDM extracts were more efficient to cell and virus pretreatment assays, and the first has showed higher antiviral activity than EBDM during viral adsorption. The EBCI and EBCS extracts have presented antiviral activity very similar in cell pre-treatment assay. EBCI was more efficient in the reduction of DENV-2 adsorption in Vero cell. However, EBCS has showed more efficient in cell pre-treatment and penetration assays. Between the extracts evaluated, EBCS seems to be more effective against DENV-2. These results have showed potential action of extracts rich in sulfated polysaccharides with antivirus activity, suggesting that they act in the initials steps of infection process of DENV-2.
596

Estado nutricional bioqu?mico de vitamina A de parturientes atendidas na cidade de Natal-RN

Gurgel, Cristiane Santos S?nzio 28 June 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-10T16:42:15Z No. of bitstreams: 1 CristianeSantosSanzioGurgel_TESE.pdf: 4190612 bytes, checksum: 773e7fec68bad460acc07eb6d8f76c81 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-10T21:19:07Z (GMT) No. of bitstreams: 1 CristianeSantosSanzioGurgel_TESE.pdf: 4190612 bytes, checksum: 773e7fec68bad460acc07eb6d8f76c81 (MD5) / Made available in DSpace on 2017-02-10T21:19:07Z (GMT). No. of bitstreams: 1 CristianeSantosSanzioGurgel_TESE.pdf: 4190612 bytes, checksum: 773e7fec68bad460acc07eb6d8f76c81 (MD5) Previous issue date: 2016-06-28 / Este estudo objetivou avaliar o estado de vitamina A de pu?rperas atendidas durante o parto na cidade de Natal/RN. Foram recrutadas no estudo 793 mulheres, 60.1% (n=485) da rede p?blica e 39.0% (n=310) a rede privada. Amostras de soro (n=619) e leite colostro (n=656) foram coletadas em ambiente hospitalar, ap?s jejum noturno. O leite maduro (n=154) foi coletado trinta dias ap?s o parto, em visita domiciliar. Os indicadores bioqu?micos (retinol no soro e leite materno) foram avaliados por local de moradia (capital vs interior) e por rede de atendimento em sa?de (p?blico vs privado). O consumo de vitamina A foi avaliado referente ao ?ltimo trimestre gestacional. Para avaliar as diferentes formas de suplementa??o materna com vitamina A e suas associa??es com os indicadores bioqu?micos (soro e leite materno) formaram-se subgrupos baseados nas suplementa??es que ocorreram durante a gesta??o: GC, F1, F2, F3 e no p?s-parto: GM. O retinol das amostras foi quantificado por cromatografia l?quida de alta efici?ncia (CLAE). Para o total de mulheres, a concentra??o m?dia de retinol s?rico foi de 41.8 ? 12.9?g/dL e a preval?ncia da DVA foi de 5.3% (n= 33) com retinol (<20 ?g/dL), com diferen?a significativa entre o retinol s?rico das mulheres provenientes da capital e do interior (p<0,01). Em Natal, as preval?ncias de defici?ncia encontradas nas regi?es norte, sul, leste e oeste foram respectivamente: 4.3% (n=6), 5.6% (n=7), 2.9% (n=3) e 11.9% (n=8). A m?dia de retinol no colostro no grupo total foi de 95,3+ 53.7?g/dL, entretanto 27.3% (n=179) apresentaram valores inadequados (<60 ?g/dL). Os valores m?dios estimados de retinol fornecido aos rec?m-nascidos atrav?s do colostro, n?o atingiram a recomenda??o m?nima de 400?g/RAE/dia da AI (Adequate Intake) para rec?m-nascidos, considerando a ingest?o de 396mL/dia. Houve diferen?a significativa entre o retinol no colostro das mulheres da capital e aquelas provenientes do interior (p<0.01). Ambos os grupos n?o forneceram a AI de vitamina A para o rec?m-nascido e tamb?m o mesmo foi observado com as lactantes das regi?es norte e oeste da cidade de Natal. No leite maduro, nenhum dos grupos de mulheres das diferentes regi?es atingiu a recomenda??o, considerando a ingest?o de 780mL/dia pelos rec?m-nascidos. Ao avaliar as pu?rperas separadamente por rede de atendimento em sa?de (p?blico vs privado) foi encontrada diferen?a significativa entre o retinol s?rico e retinol no colostro (p<0.0001), mas n?o houve diferen?a para o leite maduro (p>0.05). Na estimativa do fornecimento de retinol atrav?s do colostro e leite maduro, as mulheres da rede p?blica n?o forneceram vitamina A dentro da recomenda??o m?nima para o rec?m-nascido (AI=400?g/RAE/dia), ao contr?rio das mulheres da rede privada, que forneceram. O consumo diet?tico m?dio total de vitamina A das parturientes foi de 987.1 + 674.4 ?gRAE/dia, sendo 872.2 + 639.2 ?gRAE/dia na da rede p?blica e 1169.2 + 695.2 ?gRAE/dia na rede privada, com diferen?a altamente significativa (p<0,00001). Na avalia??o individual, 38.4% (n=100) e 17.3% (n=28) das mulheres das redes p?blica e privada tinham ingest?o abaixo da ideal. Ao se estudar as diferentes formas de suplementa??o com vitamina A, n?o foram encontrados casos de DVA nos grupos suplementados com F1, F2 e F3. Ao se analisar o efeito da suplementa??o sobre o retinol do colostro, o grupo F2 (betacaroteno) apresentou mais casos de inadequa??o (40%). Os grupos F2 e GM n?o forneceram a quantidade de retinol m?nima recomendada pela AI aos rec?m-nascidos. No retinol do leite maduro n?o houve diferen?a entre os grupos GC, F1, F2, F3 e GM e com percentuais de inadequa??o mais baixos no GM (14.3%) e os grupos GC e F2 n?o forneceram a quantidade de retinol m?nima recomendada pela AI para os rec?m-nascidos. Concluiu-se que a preval?ncia de DVA entre as pu?rperas atendidas em Natal foi considerada um problema "leve" de sa?de p?blica na popula??o em geral. Os grupos de alto risco neste estudo viviam em cidades do interior, eram atendidos na rede p?blica de sa?de e n?o tomavam vitamina A, como o suplemento regular durante a gesta??o. / This study aimed to evaluate the vitamin A status of women who delivered in Natal/RN. A total of 795 women were enrolled in the study. Serum (n=619) and colostrum (n=656) samples were collected in the hospital after an overnight fast. Mature milk samples (n=15) were collected at the women?s house thirty days after delivery. Biochemical indicators were evaluated according to home location (capital city vs. country towns) and type of health care system (public vs. private). Vitamin A intake was assessed using a food-frequency questionnaire (FFQ) corresponding to the last trimester of pregnancy. In order to evaluate the different forms of maternal supplementation with vitamin A and their associations with biochemical markers (maternal serum and breast milk), subgroups were formed based on the type of supplementation that occurred during pregnancy: GC, F1, F2, F3 and postpartum: GM. Retinol concentrations in the biological samples were quantified by high performance liquid chromatography (HPLC). For the total sample, the mean serum retinol concentration was 41.8 ?12.9?g/dL and the prevalence of VAD was 5.3% (n=33) of women presenting retinol concentrations (<20 ?g/dL), evidencing a significant difference in serum retinol concentrations between women from the capital city and from the countryside (p <0.01). In Natal, the prevalence of disability found in the north, south, east and west were, respectively, 4.3% (n= 6), 5.6% (n= 7), 2.9% (n= 3) and 11.9% (n= 8). The overall mean retinol concentration in colostrum was 95.3 ? 53.7?g/dL; however, 27.3% (n=179) of women presented inadequate values (<60 ?g/dL). The average estimated amounts of retinol provided to newborns through colostrum did not meet the minimum recommendation of 400 ?g/RAE/day of AI (Adequate Intake) for newborns in both groups, considering the intake of 396mL/day. It was found a significant difference in colostrum retinol concentrations between women from the capital city and from the countryside (p<0.01). In Natal, colostrum milk of women from the northern and western regions did not meet the AI. For mature milk, none of the groups from the different regions met the recommendation, considering the intake of 780mL/day. Evaluating the sample separately by childbirth care system (public vs. private), it was found a significant difference in serum and colostrum retinol concentrations between the groups (p <0.0001); there was no difference for the mature milk (p>0.05). Estimating the retinol supply through colostrum and mature milk, women attending the public health system did not provide the minimum vitamin A amount recommended for newborns (AI= 400?g/RAE/day), unlike women's private network, which provided. The average total dietary vitamin A intake of pregnant women was 987.1 ? 674.4 ?gRAE/day, was 872.2 + 639.2 ?gRAE/day for women attending the public health system and 1169.2 + 695.2 ?gRAE/day for those attending the private system, evidencing a highly significant difference (p<0.001). Individually assessing the participants, 38.4% (n=100) e 17.3% (n=28) of women in the public and private systems had vitamin A intakes below the ideal. There was no difference in serum retinol concentrations between the CG, F1, F2, F3 and MG groups (p<0.05), although only the supplemented groups F1, F2 and F3 had no cases of VAD. Regarding colostrum retinol levels, the F2 group (beta-carotene) presented the highest number of inadequate cases (40%). The F2 and MG groups did not provide the minimum amount of retinol recommended by AI for newborns. Regarding retinol concentrations in mature milk, there was no difference between the CG, F1, F2, F3 and MG groups, and the MG group presented the lowest percentage of inadequacy (14.3%), while the CG and F2 groups did not provide the minimum amount of retinol recommended by the AI for infants. It was concluded that the prevalence of VAD among mothers who delivered in Natal was considered a ?mild? public health problem in the overall population. High-risk groups in this study lived in towns, were attended in the public health system and did not take vitamin A as regular supplement during pregnancy.
597

Characterization of RadA/Sms from Chromobacterium violaceum and discovery of a new episome

Lima, Daniel Chaves de 23 September 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-17T19:43:31Z No. of bitstreams: 1 DanielChavesDeLima_TESE.pdf: 22514409 bytes, checksum: 31f3c8faf388b52b979837aa634b9a04 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-20T18:50:56Z (GMT) No. of bitstreams: 1 DanielChavesDeLima_TESE.pdf: 22514409 bytes, checksum: 31f3c8faf388b52b979837aa634b9a04 (MD5) / Made available in DSpace on 2017-02-20T18:50:56Z (GMT). No. of bitstreams: 1 DanielChavesDeLima_TESE.pdf: 22514409 bytes, checksum: 31f3c8faf388b52b979837aa634b9a04 (MD5) Previous issue date: 2016-09-23 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Chromobacterium violaceum is a ?-proteobacteria commonly found around tropical and subtropical regions throughout the globe. It produces many metabolites with biotechnological properties such as antitumoral peptides, antibiotics and polymers that have potential to replace the oil-based ones. Although it has been extensively studied over the past 40 years, there are many aspects of C. violaceum that remains unclear until today. We have conducted a biochemical study on the homologous recombination (HR) machinery of C. violaceum, mainly in RecA and its paralog, RadA/Sms. We performed in vitro assays from initial and late steps of HR such as D-loop formation and branch migration, respectively, with their corresponding molecular actors and how RadA/Sms influenced each one. We observed cvRadA/Sms influences negatively D-loop formation promoted by cvRecA and through pull-down assay we have observed an interaction between these two proteins. We also observed the DNA-binding preference of cvRadA/Sms and cvRecA and observed that this protein binds preferentially to dsDNA instead ssDNA, unlike cvRecA. No involvement of cvRadA/Sms on branch migration reactions was detected. In this work, we also described, for the first time, the isolation, sequencing and annotation of a new plasmid from C. violaceum, which we named ChVi1 and has 44,236 base pairs, 39 predicted open reading frames (ORFs) and, possibly, two origins of replication. Most of the ORFs codes for hypothetical and structural bacteriophage proteins. By using restriction digestion and Next-generation sequencing (NGS) we also looked for the presence of a similar plasmid in other seven C. violaceum strains isolated from amazon region. Our analysis suggest the presence of a plasmid similar to ChVi1 in two of these strains. The present work describes for the first time a biochemical characterization of RadA/Sms and RecA from C. violaceum which have different roles in HR. Moreover, the discovery of ChVi1 opens a path to further explore C. violaceum?s biology.
598

Produ??o, purifica??o e caracteriza??o de uma celulase termost?vel e halotolerante de uma linhagem marinha de Bacillus sp.

Santos, Yago Queiroz dos 16 June 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-21T00:14:47Z No. of bitstreams: 1 YagoQueirozDosSantos_DISSERT.pdf: 1419350 bytes, checksum: 3ae7b369d8ed52af2d85454e8aa5fdbb (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-03T21:49:39Z (GMT) No. of bitstreams: 1 YagoQueirozDosSantos_DISSERT.pdf: 1419350 bytes, checksum: 3ae7b369d8ed52af2d85454e8aa5fdbb (MD5) / Made available in DSpace on 2017-03-03T21:49:40Z (GMT). No. of bitstreams: 1 YagoQueirozDosSantos_DISSERT.pdf: 1419350 bytes, checksum: 3ae7b369d8ed52af2d85454e8aa5fdbb (MD5) Previous issue date: 2016-06-16 / A atual demanda por fontes de energia renov?veis tem impulsionado a busca de alternativas capazes de substituir o uso de combust?veis f?sseis. Uma das inova??es mais promissoras para impactar positivamente o cen?rio mundial de energia ? a produ??o de bioetanol de segunda gera??o (B2G), derivado de monossacar?deos obtidos a partir da degrada??o enzim?tica de material lignocelul?sico que normalmente ? descartado nos atuais processos agroindustriais. No presente trabalho, uma celulase halotolerante secretada por uma linhagem marinha Bacillus sp. SR22 com grande resist?ncia ?s mudan?as de temperatura e pH foi isolada e caracterizada. A endoglucanase de massa aproximada de 37.35 kDa nomeada como Bc22Cel foi purificada por precipita??o de sulfato de am?nio, cromatografia de gel filtra??o e extra??o do gel ap?s eletroforese em gel de poliacrilamida em condi??es nativas. O valor ideal de pH e temperatura de Bc22Cel foram 6,5 e 60 ? C, respectivamente. A enzima purificada demonstrou consider?vel propriedade halof?lica ao manter mais de 70% de atividade residual mesmo quando pr?-incubadas com 1,5 M de NaCl durante 1 hora. Ap?s a an?lise cin?tica de enzima purificada os valores de Km e Vmax foram estabelecidos em 0,3953 nmol.ml-1 e 0,0167 ?mol.ml-1.min-1, respectivamente. Avaliados conjuntamente, os presentes dados apontam a Bc22Cel como uma candidata potencial para aplica??es industriais de degrada??o de celulose. / The current demand for environment-friendly renewable energy sources has driven the search for alternatives capable of replacing the use of fossil fuels. One of the most promising innovations to positively impact the world energy scenario is the second-generation bioethanol production (B2G) from reducing sugars derived from enzymatic degradation of lignocellulosic material that is ordinarily discarded at agroindustrial processes. In this work, a salt-tolerant cellulase secreted by a marine Bacillus sp. SR22 strain with wide resistance to temperature and pH was isolated and characterized. The 37.35 kDa endoglucanase named as Bc22Cel was purified by ammonium sulphate precipitation, gel filtration chromatography and extraction from the gel after non-reducing sodium dodecylsufate-polyacrylamide gel electrophoresis. The optimal pH value and temperature of Bc22Cel were 6.5 and 60 ?C, respectively. The purified Bc22Cel showed a considerable halophilic property being able to maintain more than 70% of residual activity even when pre-incubated with 1.5 M NaCl for 1 hour. Kinetic analysis of purified enzyme showed the Km and Vmax to be 0,3953 nmol ml-1 and 0,0167 ?mol ml-1 min-1, respectively. Taking together, the present data indicates the Bc22Cel as a potential and useful candidate for industrial applications.
599

Obten??o de polissacar?deos sulfatados da alga vermelha comest?vel Gracilaria birdiae e sua influ?ncia na forma??o e morfologia de cristais de oxalato de c?lcio

Santos, Pablo de Castro 30 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T20:08:05Z No. of bitstreams: 1 PabloDeCastroSantos_TESE.pdf: 3735284 bytes, checksum: 5bc846ee3890e15ca33dc1e32e7349d8 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-13T20:05:04Z (GMT) No. of bitstreams: 1 PabloDeCastroSantos_TESE.pdf: 3735284 bytes, checksum: 5bc846ee3890e15ca33dc1e32e7349d8 (MD5) / Made available in DSpace on 2017-03-13T20:05:04Z (GMT). No. of bitstreams: 1 PabloDeCastroSantos_TESE.pdf: 3735284 bytes, checksum: 5bc846ee3890e15ca33dc1e32e7349d8 (MD5) Previous issue date: 2016-08-30 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A urolit?ase afeta aproximadamente 10% da popula??o mundial e est? associada fortemente a presen?a de cristais de oxalato de c?lcio (OxCa). Atualmente n?o existe nenhum composto eficiente que pode ser utilizado para prevenir esta doen?a. No entanto, alguns polissacar?deos sulfatados (PS) de algas marinhas marrons demonstraram capacidade de inibir a forma??o de cristais de OxCa e alterar a morfologia destes in vitro. Os PS da alga vermelha Gracilaria birdiae t?m atividades biol?gicas importantes, mas at? o presente momento n?o foi avaliada como inibidora da forma??o de cristais de OxCa. O presente estudo teve como objetivo obter PS e verificar seu efeito na forma??o do OxCa. Para tal, extratos ricos em polissacar?deos foram obtidos utilizando extra??o alcalina, sonica??o, digest?o proteol?tica, seguida por precipita??o com etanol. Esses extratos ricos em PS (EB) foram separados em 5 fra??es (F-0.25; F-0.5; F-0.75; F-1.0 e F-1.25) atrav?s de cromatografia de troca i?nica DEAE-celulose. A eletroforese em gel de agarose, infra vermelho e an?lises qu?micas mostraram que essas fra??es cont?m o mesmo pool de polissacar?deos sulfatados ricos em galactose. F-0.25; F-0.5; F-0.75; F-1.0 foram capazes de inibir etapas importantes da forma??o dos cristais de OxCa, como a nuclea??o e agrega??o, no entanto a F-0.25 promoveu a maior inibi??o da nuclea??o em 76,92% e da agrega??o em 68,57%. As fra??es F-0.25 e F-0.5 foram capazes de inibir em 6 e 7 vezes, respectivamente, o n?mero de cristais OxCa monohidratados (COM) formados in vitro, enquanto que as fra??es F-0.75 e F-1.0, reduziram apenas em 1,5 vezes. A morfologia dos cristais de OxCa foi afetada principalmente pelas amostras, EB, F-0.25; F-0.5 e F-0.75, pois promoveram as varia??es mais destoantes em rela??o ao controle. A an?lise do potencial zeta (?) dos cristais formados na presen?a das amostras, constatou um aumento de cargas negativas em suas superf?cies. Atrav?s das imagens obtidas por microscopia de fluoresc?ncia, foi constatado que os PS est?o distribu?dos de forma homog?nea nos cristais dihidratados (COD) e de forma perif?rica nos COM. Os dados obtidos atrav?s da microscopia eletr?nica de varredura(MEV) e espectroscopia de energia dispersiva (EDS) revelaram grandes varia??es na distribui??o de ?tomos de oxig?nio e c?lcio na superf?cie dos cristais na presen?a das F-0.25 e F-0.5. A c?lulas renais HEK-293, MDCK e 786-0 tiveram baixa toxicidade na presen?a do extrato bruto e das fra??es F-0.25; F-0.5; F-0.75. Estas amostras protegeram c?lulas renais MDCK e verificou-se um efeito reparador contra danos causados pelo H2O2 e OxCa. Por fim, as c?lulas MDCK submetidas ao tratamento pr?vio e simult?neo com a F-0.25 e a F-0.5 na presen?a de H2O2 e OxCa, reduziram a atividade das enzimas super?xido dismutase (SOD) e catalase (CAT). Com isto, verifica-se que PS da G. birdiae podem ser potenciais alvos farmacol?gicos do ponto de vista preventivo, terap?utico e reparador de danos causados pela urolit?ase, por?m ? importante que outros estudos sejam realizados in vivo, bem como, sejam realizados experimentos para elucidar os mecanismos precisos de a??o, pelos quais estes PS protegem as c?lulas contra danos por H2O2. / The urolithiasis disease affects approximately 10% of the world's population and is strongly associated calcium oxalate crystals (CaOx). Until now, there is not an efficient compound that can be used to prevent this disease. However, some sulfated polysaccharides (SP) from brown seaweeds exhibited an ability to inhibit the formation of CaOx crystals and change the morphology in vitro. SP from the red seaweed Gracilaria birdiae has important biological activities, but they have not been evaluated as inhibitor of CaOx crystals formation. This study aimed to obtain SP from this seaweed and evaluate their effect on CaOx crystals formation. Thus, sulfated polysaccharide-rich extract (EC) was obtained using alkaline extraction, sonication, proteolytic digestion followed by ethanol precipitation. This extract was fractionated into five fractions (F-0.25; F-0.5; F-0.75; F-1.0; F-1.25) by DEAE-cellulose ion-exchange chromatography. Agarose gel electrophoresis, infrared and chemical analysis showed that these fractions contain the same pool of sulfated galactose-rich polysaccharides. F-0.25; F-0.5; F, 0.75; F-1.0 were able to inhibit important formation steps of the CaOx crystals, as nucleation and aggregation, we highlight F-0.25 that promoted the highest inhibition of nucleation in 76.92% and aggregation in 68.57%. The F-0.25 and F-0.5 fractions were able to reduce approximately 6 and 7 times, respectively, the number of these CaOx monohydrated crystals (COM) formed in vitro, whereas F-0.75 and F-1.0 fractions reduced this number only 1.5 times. The morphology of CaOX crystals was mainly affected by the samples EC, F-0.25; F-0.5 and F-0.75, they promoted the most discordant variations in the control. The analysis of the zeta potential (?) of the crystals formed in the presence of the samples was found an increase of negative charges on their surfaces. Through the images obtained by fluorescence microscopy revealed that the PS are distributed homogeneously in the dehydrated crystals (COD) and peripherally in COM. The data obtained by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) revealed wide variations in the distribution of oxygen and calcium atoms on the surface of the crystals in the presence of F-0.25 and F-0.5. The kidney cells HEK-293, MDCK and 786-0 showed low toxicity in the presence of EC and fractions F-0.25; F-0.5; F, 0.75. These samples protected kidney MDCK cells against damage caused by H2O2 and CaOx. Finally, the MDCK cells treated beforehand and concomitant with both F-0.25 and F-0.5 in the presence of H2O2 and CaOx, reduced the activity of superoxide dismutase and catalase enzymes. Overall, the data showed that PS G. birdiae may be potential pharmacological targets for preventive, therapeutic and repairing damage caused by urolithiasis. However, it is important that to make set in vivo experiments, as well as, experiments to elucidate the precise mechanism of action by which these PS protect the H2O2 damage on cells.
600

Purifica??o e caracteriza??o de uma nova lectina com atividade imunomoduladora da esponja Aplysina fulva

Santos, Paula Ivani Medeiros dos 10 July 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T20:08:05Z No. of bitstreams: 1 PaulaIvaniMedeirosDosSantos_TESE.pdf: 2576570 bytes, checksum: ad723940125128ab00057ee1698f195a (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-13T20:16:47Z (GMT) No. of bitstreams: 1 PaulaIvaniMedeirosDosSantos_TESE.pdf: 2576570 bytes, checksum: ad723940125128ab00057ee1698f195a (MD5) / Made available in DSpace on 2017-03-13T20:16:47Z (GMT). No. of bitstreams: 1 PaulaIvaniMedeirosDosSantos_TESE.pdf: 2576570 bytes, checksum: ad723940125128ab00057ee1698f195a (MD5) Previous issue date: 2015-07-10 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / As esponjas marinhas se apresentam como uma rica fonte de novos compostos bioativos de grande interesse biotecnol?gico, vimos, neste trabalho, relatar a purifica??o e caracteriza??o de uma lectina da esp?cie Aplysina fulva, denominada AFL com atividade imunomoduladora, bem como avaliar se a mesma possue efeito citot?xico sobre c?lulas em cultura (normais, tumorais e leishmanias). As prote?nas totais foram extra?das da esponja com tamp?o Tris-HCl 20 mM, pH 7,5, e fracionadas por precipita??o com acetona. A fra??o obtida com 1 volume de acetona possu?a maior atividade hemaglutinante e foi submetida a uma cromatografia em matriz de goma guar com tamp?o tetraborato de s?dio 20 mM, pH 7,5. Em seguida foi aplicada em uma coluna de Superdex 75 (FPLC-AKTA) contendo tamp?o Tris- HCl 20 mM, pH 7,5. A pureza da lectina foi atestada em uma coluna HILIC (HPLC). A sequ?ncia de 15 res?duos de amino?cidos do N-terminal da lectina foi determinada por degrada??o de Edman e n?o apresentou similaridade com nenhuma outra prote?na dos bancos de dados mais conhecidos. A massa foi estabelecida em 62 kDa, por gel filtra??o em Superdex 75. An?lise ap?s tratamento com agentes redutores permitiu deduzir que AFL ? uma prote?na homotetram?rica. Sua atividade hemaglutinante foi reduzida quando a lectina foi exposta em meio ?cido (pH < 4) ou quando submetida a temperaturas acima de 60 ?C. AFL apresentou especificidade para lactose e parcial para D-glicose e D-galactose. A lectina purificada AFL n?o apresentou efeito citot?xico para as linhagens de c?lulas cancer?genas (PANC, HeLa, HT-29, Bf16F10, A549) e de fibroblastos (MRC5). AFL foi capaz de aglutinar formas promastigotas vivas de Leishmania amazonensis e Leishmania. braziliensis,e teve sua atividade revertida pela adi??o de lactose ao ensaio. AFL n?o diminuiu de forma significante a viabilidade de Leishmania amazonensis. A lectina AFL apresentou atividade mitog?nica em concentra??es a partir de 40 ?g/mL para c?lula mononucleares do sangue perif?rico (mon?citos e linf?citos). A lectina AFL foi capaz de induzir na linhagem de macr?fagos (RAW264.7) de murinos a libera??o de TNF- ?, mas n?o de IL-6, na concentra??o de 10,0 ?g/mL. Quando AFL foi incubada com c?lulas espl?nicas de camundongos BALB/c, foi capaz de estimular a produ??o de IFN-? e promover a diferencia??o de c?lulas T para uma resposta imune celular do tipo Th1. A capacidade de modular a resposta imune do tipo Th1 jamais foi relatada em lectinas de esponjas marinhas. Todos os resultados corroboram com o alto potencial que a lectina AFL apresenta como uma nova mol?cula capaz de modular o sistema imune, podendo ser utilizada como adjuvante de vacinas contra microrganismos, dentre eles, os do g?nero leishmania. / Marine sponges are presented as a rich source of new bioactive compounds of great biotechnological interest. Here in this research we report the purification and characterization of a lectin from Aplysina fulva species, called AFL, that presents immunomodulatory activity, and it was also evaluated whether it possesses cytotoxic effects on cultured cells (normal, tumor and Leishmania). Total proteins were extracted from the sponge with Tris-HCl buffer 20 mM, pH 7.5, and fractionated by precipitation with acetone. The fraction obtained with 1 volume of acetone had greater hemagglutinating activity and was subjected to a column chromatography on guar gum matrix with 20 mM sodium tetraborate buffer, pH 7.5. It was then applied to a Superdex 75 column (AKTA-FPLC) containing 20 mM Tris-HCl buffer, pH 7.5. The purity of the lectin was attested in a HILIC (HPLC) column. The sequence of 15 residues of N-terminal amino acid of the lectin was determined by Edman degradation and showed no similarity to any other protein of the known databases. The molecular mass was set at 62 kDa by gel filtration on Superdex 75. Analysis after treatment with reducing agents enabled to deduce that the AFL is a homotetrameryc protein. Their hemagglutinating activity was reduced when the lectin was exposed in an acidic medium (pH <4) or when subjected to temperatures above 60 ? C. AFL showed specificity for partial lactose and D-glucose and D-galactose. The purified lectin LFA showed no cytotoxic effect on cancer cell lines (PANC, HeLa, HT-29, Bf16F10, A549) and fibroblast (MRC5). AFL was able to agglutinate living promastigotes of Leishmania amazonensis and Leishmania braziliensis, and had their activity reversed by the addition of lactose to the test. AFL did not decrease significantly the viability of Leishmania amazonensis. The AFL lectin showed mitogenic activity at concentrations from 40 ug / ml for mononuclear peripheral blood cells (lymphocytes and monocytes). The AFL lectin was able of induce the macrophage murine lineage (RAW264.7) release of TNF-?, but not IL-6 at a concentration of 10.0 mg / mL. When LPA was incubated with spleen cells from BALB / c mice was able to stimulate the production of IFN-? and to promote the differentiation of T cells to a cellular Th1 immune response. The ability to modulate the immune response of the Th1-type lectins has never been reported in marine sponges. All results confirm the high potential that the lectin AFL, that appears as a new molecule capable of modulating the immune system and can be used as an adjuvant for vaccines against microorganisms, including the gender Leishmania.

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