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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.
61

The therapeutic value of Aloe Ferox Mill

Mhaladi, Refilwe January 2014 (has links)
Thesis (M. Tech. (Biomedical Technology)) -- Central University of Technology, 2014 / The rising costs of health care, the outbreak of drug resistant organisms, health depleting lifestyles and the risky side effects of currently used drugs are world-wide problems. This has led to the search for novel drugs and drug leads. Traditional healers and other individuals across the globe possess unlimited knowledge on the healing powers of different plants that has been passed on through generations. This knowledge together with scientific investigations can lead to the eradication of most of the diseases either by treatment or prevention. Aloe ferox Mill. is one of the plants that have gained a lot of interest from the pharmaceutical industry. The plant has over 80 documented medicinal uses. These include treatment of impotence and infertility, sexually transmitted infections, arthritis, hypertension, leukaemia, bacterial and fungal infections. It is also known as a blood purifier, widely used as a laxative and anti- inflammatory agent. More research is required to discover more about A. ferox and its benefits to health as well as to investigate its potential for the development of novel drugs. The current study was focused at investigating the anti- cancer, anti- microbial antidiabetic, cytotoxic activities and phytochemical composition of leaf extracts of A. ferox. Three cancer cell lines namely: breast (MCF7), colon (HCT116) and prostate (PC3) cancer cell lines were used to investigate the anticancer activity of the extracts using the Sulforhodamine B (SRB) method. To determine the anti- diabetic activity of the plant extracts the C2C12 and Chang cell in- vitro models of glucose uptake were used. The micro- dilution technique was IV used to evaluate the antibacterial and antifungal activity of the extract. The safety of these extracts against normal human foetal lung fibroblasts (W138), Chang and C2C12 cells was done by through the SRB and the MTT methods. To determine the phytochemical profile of A. ferox the DPPH radical scavenging and the Folin Ciocalteu methods were used to test the antioxidant activity and the total phenolic content of the different extracts respectively. Different methods were used to determine the presence of phytochemicals such as steroids, saponins, alkaloids, carbohydrates and flavonoids. LCMS was also done to detect the elemental composition of the plant extracts. According to the CSIR criteria A. ferox was inactive against the cancer cell lines used. It however exhibited antioxidant activity even at low concentrations, with an EC50 of 0.865 ± 0.783. The methanol extract showed more phenolic content than the dichloromethane and aqueous extracts at a concentration of 5mg/ml. It is believed that the antioxidant activity correlates with the phenolic content and quality of the phenols present in the plant and more assays have to be done to prove this hypothesis. Other phytochemicals found in the extract included saponins, steroids, alkaloids as well as flavonoids. Both the methanol and aqueous extracts of A. ferox caused a significant increase in glucose uptake by C2C12 cells but caused a slightly decreased uptake by the Chang cells. The plant extracts inhibited the growth of Staphylococcus epidermidis, Streptococcus pneumonia, Escherichia coli and Candida albicans at a concentration of 15mg/ml extract. Candida tropicalis and Escherichia faecalis were resistant to A. ferox extracts. Finally the extracts showed no toxic activity against the normal foetal lung fibroblasts, Chang and C2C12 cells validating the safety of this plant for human use. V The results in conjunction with literature findings show A. ferox to be a promising source of drugs and therapeutic agents. Due to the fact that traditional healers already rely on it as treatment for different ailments, it is important that the safety of the plant for use has been validated though other studies and clinical trial still need to be done to fully confirm this. All the information gathered also showed this plant to be of great benefit against major health problems, responsible for millions of deaths each year such as cancer, cardiovascular and inflammatory diseases, and diabetes. There is however still a great need for more investigation to be done on this plant against a vast majority of organisms and diseases so as to fully benefit from it.
62

CARATTERIZZAZIONE FITOCHIMICA ED ATTIVITA' BIOLOGICA DI PIANTE DEL GENERE ALOE / Phytochemical characterization and biological activity of plants of the genus Aloe

PELLIZZONI, MARCO 23 February 2012 (has links)
In questo lavoro scientifico è stato studiato il contenuto di aloine e beta-polisaccaridi in piante di Aloe barbadensis (Aloe vera) ed Aloe arborescens, in relazione ad alcuni fattori di variabilità quali la specie, l’età, la tipologia di tessuto vegetale analizzato e le condizioni di coltivazione. Ulteriori analisi hanno permesso di studiare la loro stabilità in differenti matrici, il loro potere antiossidante ed antimicrobico, mediante studi in vitro. E’ stato inoltre effettuato un ulteriore studio, in vivo, somministrando un omogeneizzato d’Aloe arborescens fresco a bovine da latte in periparto, con lo scopo di valutare l’eventuale assorbimento di aloina, correlandolo ad eventuali effetti benefici. Nel derma è concentrata l’aloina, molto abbondante in piante di tre anni, mentre nella porzione fogliare interna gelatinosa, i beta-polisaccaridi. Il profilo fitochimico inoltre pare essere influenzato dalle condizioni di stress cui la coltura viene sottoposta, in particolare sembra che lo stress salino e la scarsa disponibilità in azoto, promuovano la sintesi delle principali bio-componenti studiate. Lo stesso contenuto inoltre è stato positivamente correlato al grado di luminosità percepita dalla coltura. Entrambe le componenti sono poco stabili e molto sensibili alle alte temperature, presentano inoltre ridotta capacità antiossidante. In sinergia con altre biocomponenti, pare possiedano proprietà antimicrobiche contro alcuni batteri patogeni, mentre entro certe dosi mostrano effetti pre-biotici, nei confronti di alcuni lattobacilli. E’ stato infine dimostrato dalla sperimentazione in vivo un assorbimento ematico di aloina, dimostrando in questo modo la sua sistemicità. / The relationship between Aloe main active components and plant age, specie and grow conditions has been investigated in Aloe barbadensis and A. arborescens, the commercially most used species of the genus. Aloin was mainly located in leaves outer green rid while beta-polysaccharides in inner parenchyma. Aloin concentration was higher in younger plants. Plants grown under decrising light intensities showed lower aloin and beta-polysaccharides concentrations. The content of these substances is improved by stress condition. The most antioxidant activity is located in the outer green rid of the leaves and it was slightly correlated to the total phenolic compounds content. Aloin and beta-polysaccharides stability in leaf homogenate was poor and temperature seemed to be quite more effective in reducing degradation. Antimicrobial effect against to phatogen microorganisms of anthraquinones aloin and alo-emodin and different Aloe extracts was confirmed. Prebiotic effects to Lactobacillus were discovered and a synergistic effect of several compounds was supposed. Systemic effect of aloin was explained by vivo experiments (on cows) because aloin is observed until 24 h after the oral administration of Aloe, thus metabolic and physiologic effects may be expected.
63

Otimização de protocolos de criopreservação do sêmen de catetos (Pecari tajacu LINNEAUS, 1758) / Cryopreservation protocols optimization of semen collared peccaries (Pecari tajacu Linneaus, 1976)

Souza, Ana Liza Paz 10 February 2015 (has links)
Made available in DSpace on 2016-08-15T20:27:56Z (GMT). No. of bitstreams: 1 AnaLPS_DISSERT.pdf: 2906365 bytes, checksum: 9332744a34f68778b08f8668337ce882 (MD5) Previous issue date: 2015-02-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present thesis had as objective optimized peccaries semen cryopreservation protocols (Pecari tajacu). Therefore, adult animals were used originated from the Multiplication Center of Wild Animals (CEMAS) of the Federal Rural University of the Semi-Arid (UFERSA), which semen was collected by electroejaculation and immediately evaluated. The first experiment aimed at evaluating the effect of low-density lipoprotein (LDL) purified in relation to egg yolk (G) and defines the ideal concentration (20%, 10% and 5%) for semen cryopreservation in peccaries. After the data analysis it was found that LDL (20%) can be used to replace egg yolk having been verified 36.4 ± 5.3 and 21.8 ± 6.9% of the total sperm motility after thawing, respectively. The second experiment evaluated the action of Aloe vera gel (AV) both refrigeration and in the peccaries of semen freezing in different concentrations (20%, 10%, 5%) or associated with egg yolk (10%:10%). It was found that Aloe vera gel (20%) proved to be efficient cooling at 5 ° C, maintaining the longevity of sperm for up to 48 hours of total motility assessment having a 54.2 ± 21.3%; as the cryopreservation process, it was found that the use of Aloe vera 20% can replace egg yolk, but its association with gem promoted better preservation of viability (32.7 ± 2.3%), osmotic response (37.8 ± 4.2%) and membrane integrity (40.2 ± 3.1). In the third experiment evaluated the addition of the action (0.5% and 1.0%) of base detergent sodium dodecyl sulfate (SDS), Equex ® STM, the peccaries of semen. However, it was observed that, at any concentration proposal was effective in increasing the longevity of sperm cell peccaries over 15 minutes as previously described for the species. The experiments have been sufficient to answer the hypotheses and are useful for the improvement of semen cryopreservation protocols of collared peccary (Pecari tajacu) / A presente tese teve como objetivo aperfeiçoar protocolos de criopreservação de sêmen de catetos (Pecari tajacu). Para tanto, foram utilizados animais adultos oriundos do Centro de Multiplicação de Animais Silvestres (CEMAS) da Universidade Federal Rural do Semi-Árido (UFERSA), cujo sêmen foi coletado por eletroejaculação e imediatamente avaliado. O primeiro experimento objetivou avaliar o efeito da lipoproteína de baixa densidade (LDL) purificada, em relação à gema de ovo (G) e determinar a concentração ideal (20%, 10% e 5%) para criopreservação de sêmen em catetos. Após a análise dos dados verificou-se que a LDL (20%) pode ser utilizada em substituição à gema de ovo, tendo sido verificados 36.4±5.3% e 21.8±6.9 de motilidade espermática total após a descongelação, respectivamente. No segundo experimento, avaliou-se a ação do gel de Aloe vera (AV) tanto na refrigeração quanto na congelação do sêmen de catetos, em diferentes concentrações (20%, 10%, 5%) ou associado à gema de ovo (10%:10%). Verificou-se que o gel de Aloe vera (20%) se mostrou eficiente para a refrigeração a 5°C, mantendo a longevidade espermática por até 48 horas de avaliação apresentando uma motilidade total de 54.2±21.3%; quanto ao processo de criopreservação, verificou-se que o uso de Aloe vera a 20% pode substituir a gema de ovo, porém a associação desta com a gema promoveram a melhor preservação da viabilidade (32.7±2.3%), resposta osmótica (37.8±4.2%) e integridade de membrana (40.2±3.1). No terceiro experimento verificou-se a ação da adição (0,5% e 1,0%) do detergente a base de dodecil sulfato de sódio (SDS), Equex ® STM, no sêmen de catetos. Entretanto, observou-se que este, em nenhuma concentração proposta, foi eficiente em aumentar a longevidade da célula espérmática de catetos além dos 15 minutos, conforme previamente descrito para a espécie. Os experimentos realizados foram suficientes a responder as hipóteses propostas, sendo úteis para o aperfeiçoamento de protocolos de criopreservação de sêmen de catetos (Pecari tajacu). Palavra Chave: Cateto, Criopreservação de sêmen, Lipoproteína de baixa Densidade, Dodecil Sulfato de Sódio, Gel de Aloe vera
64

CaracterizaÃÃo fÃsico-quÃmica e estrutural de polissacarÃdeos obtidos de folhas da planta Aloe barbadensis Miller e avaliaÃÃo de suas atividades antiviral e anti-hemorrÃgica / Physico-chemical characterization and structural polysaccharides obtained from leaves of the plant Aloe barbadensis Miller and evaluation of their activities antiviral and anti-haemorrhagic

Ygor Raphael Gomes Eloy 22 March 2012 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Este trabalho teve como objetivos caracterizar fÃsico-quÃmica e estruturalmente polissacarÃdeos obtidos de folhas de Aloe barbadensis e avaliar suas atividades antiviral, anti-hemorrÃgica e prÃ-coagulante e possÃveis sinais de toxicidade. Foi realizada extraÃÃo aquosa de polissacarÃdeos totais (PT) de A. barbadensis, seguido de precipitaÃÃo por etanol e remoÃÃo dos contaminantes proteicos com TCA. A cromatografia em DEAE-celulose foi eficiente no fracionamento dos PT, onde foram obtidas as fraÃÃes PI e PII. A caracterizaÃÃo fÃsico-quÃmica mostrou que a fraÃÃo PI à composta por manose (78,4%), glucose (7,3%), galactose (2,1%), fucose (2,8%) e Ãcidos urÃnicos (10,0%), e isenta de grupos Ãster sulfato. Enquanto, a fraÃÃo PII à constituÃda por manose (39,2%), glucose (22,2%), galactose (26,3%), arabinose (3,8%), xilose (1,1%), Ãcidos urÃnicos (8,0%) e grupos Ãster sulfato (12,0%). Na revelaÃÃo das bandas polissacarÃdicas da fraÃÃo PII, obtidas por PAGE e gel de agarose corados com stainsall foi constatado a presenÃa de duas bandas que apresentaram diferentes coloraÃÃes, roxa e ciana, correspondentes a presenÃa de grupos sulfato e carboxilados, respectivamente. Na anÃlise estrutural das fraÃÃes PI e PII, por espectroscopia no IR, foi demonstrado que a fraÃÃo PI apresenta unidades monossacarÃdicas de Ã-manose O-acetiladas (812,2 e 960 onda.cm-1) e Ãcidos urÃnicos neutros (1738 onda.cm-1) em sua estrutura. Diferentemente, a fraÃÃo PII, mostrou-se ser constituÃda por unidades monossacarÃdicas de manose (1014,7 onda.cm-1), galactose (1078,2 onda.cm-1), Ãcidos urÃnicos carregados negativamente (1635 onda.cm-1) e Ãster sulfato (1329,5 e 1260,9 onda.cm-1). Na avaliaÃÃo estrutural da fraÃÃo PII por RMN foi comprovado à presenÃa do grupo Ãster sulfato. Em relaÃÃo Ãs atividades biolÃgicas, o teste de citotoxicidade mostrou que os PT e as fraÃÃes PI e PII nÃo apresentaram toxicidade para a maioria das cÃlulas testadas e nÃo foram eficientes na inibiÃÃo de vÃrus nÃo envelopados Ad-19 e Ad-41. No entanto, os PT e a fraÃÃo PI foram capazes de inibir a infecÃÃo causada por HSV-1 e HSV-2. Em ensaios com metapneumovÃrus (HMPV), a fraÃÃo PII apresentou atividade antiviral superior à ribavirina. Embora os PT e as fraÃÃes PI e PII nÃo terem apresentado atividade contra dengue vÃrus sorotipo 1 (DENV-1), os PT puderam inibir a hemorragia em ratos, diminuindo o tempo de sangramento e o tempo de protrombina. Os PT nÃo apresentaram toxicidade em camundongos, mas aumentaram o tamanho do baÃo e o nÃmero de plaquetas sanguÃneas. Pode ser concluÃdo que extratos foliares de A. barbadensis podem apresentar polissacarÃdeos neutros ou carregados negativamente por grupos carboxilados/sulfatados. Em adiÃÃo, alÃm de apresentar atividade inibitÃria contra os vÃrus HSV-1, HSV-2 e HMPV, podem tambÃm apresentar efeito anti-hemorrÃgico e prÃcoagulante, propriedades essas, importantes, visto que a complicaÃÃo de muitas viroses leva a quadros hemorrÃgicos. AlÃm disso, os PT de A. barbadensis nÃo apresentaram toxicidade expressiva, podendo ser utilizada como agente terapÃutico seguro e eficaz. / The aim of this study was to investigate the physicochemical and structural parameters of polysaccharides obtained from Aloe barbadensis leaves and to evaluate the antiviral and cytotoxic activities and procoagulant, anti-bleeding effects. In addition, toxicological analysis was carried out. The pulp was submitted to aqueous extraction (70 ÂC) and the total polysaccharides (PT) obtained by ethanol precipitation, TCA was used to remove the protein contamination. The fractionation of PT with DEAE-celulose resulted in two fractions (PI and PII). The physicochemical characterization showed that PI fraction presents mannose (78,4%), glucose (7,3%), galactose (2,1%), fucose (2,8%) and uronic acid (10,0%). Sulfate esters were not detected in PI fraction. On the other hand, PII fraction presents the monosaccharides mannose (39,2%), glucose (22,2%), galactose (26,3%), arabinose (3,8%), xylose (1,1%), uronic acids (8,0%) and sulfate esters groups (12,0%). The polysaccharidics of PII obtained by PAGE and agarose gel electrophoresis were revealed with toluidine blue and stainsall dye showing the presence of two different bands, one purple (indicative of sulfate) and another cyan (indicative of carboxilated groups). Structural analysis of PI and PII fractions by IR spectroscopy demonstrated that PI fraction is composed of residues of Ã-mannose O-acetylated (812.2 and 960 cm-1) and uronic acids (1738 cm-1). In contrast, the PII fraction is composed of mannose (1014.7 cm-1), galactose (1078.2 cm-1), negatively charged uronic acids (1635 cm-1) and sulfate ester (1329.5 and 1260.9 cm-1). These results corroborate with NMR analyses that suggest the presence of sulfate groups in PII structure. The cytotoxicity evaluation showed that PT and the fractions PI and PII did not show toxicity against most of tested cells and the same fractions were not effective against non-enveloped virus (Ad 19 and Ad 41) inhibition. However, the PT and PI fraction were able to inhibit the infection caused by HSV-1 and HSV-2. In addition, PII fraction presents antiviral activity against metapneumovirus. Although the PT and the fractions PI and PII did not show activity against dengue virus serotype 1 (DENV-1), PT could inhibit the bleeding effects in rats, reducing the bleeding and prothrombin time. The PT showed no toxicity in mice, but increased spleen size and number of blood platelets. In conclusion, A. barbadensis leaves contain neutral or negatively charged carboxylated/sulfated polysaccharides. In addition, besides having inhibitory activity against HSV-1, HSV-2 and HMPV, they can also anti-bleeding and procoagulant effect. Moreover, the PT of A. barbadensis showed no significant toxicity and can be used as a safe and effective therapeutic agent.
65

Propriedades físico-químicas de cimentos Portland e à base de MTA associados ao Aloe vera / Physicochemical properties of MTA-based and Portland cements associated to Aloe vera

Zina, Omar 13 September 2013 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-11-25T10:17:54Z No. of bitstreams: 2 Tese - Omar Zina - 2013.pdf: 1884367 bytes, checksum: ac70615bb4bc9a680a17fead9dac004b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-11-25T12:28:09Z (GMT) No. of bitstreams: 2 Tese - Omar Zina - 2013.pdf: 1884367 bytes, checksum: ac70615bb4bc9a680a17fead9dac004b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-11-25T12:28:09Z (GMT). No. of bitstreams: 2 Tese - Omar Zina - 2013.pdf: 1884367 bytes, checksum: ac70615bb4bc9a680a17fead9dac004b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-09-13 / The aim of this study was to determine the solution-powder ration and to evaluate the setting time, solubility, dimensional change, pH and radiopacity of White structural and non-structural Portland cement, ProRoot MTA® and MTA BIO® associated to 2% glycolic solution of Aloe vera. Five samples of each material were used for each test according to American National Standards Institute/American Dental Association specification 57. Statistical analyses were carried out using ANOVA and Tukey’s test at 5% level of significance. When sample distribution was non-normal, nonparametric analysis of variance were performed with Kruskal-Wallis test (α=0.05). The results revealed no statistical difference in the water-powder ratio among the tested materials. ProRoot MTA® had the longest setting time (116.50 ± 4.08) (P<0.05). White structural and nonstructural Portland cements did not have means values on the radiopacity test (109.76 ± 10.40 and 118.75 ± 15.44, respectively) in accordance with ANSI/ADA, being significantly different from the MTA-based cements (P<0.05), and demonstrated higher mean solubility values (2.30 ± 0.36 and 2.81 ± 0.40, respectively) (P<0.05). The values for dimensional change of all tested materials were considered acceptable by ANSI/ADA. There were no significant differences between the mean pH values recorded for the materials (p>0.05). It was alkaline from the beginning to the end of the tests. MTA BIO presented lower setting time and lower solubility. The cements did not showed a higher solubility than 3%. All the assessed cements showed acceptable values of dimensional variation and high pH during the test time. MTA BIO and ProRoot MTA had adequate radiopacity values. / Esse estudo teve como objetivo determinar propriedades físico-químicas dos cimentos Portland branco estrutural e não estrutural, ProRoot MTA® e MTA BIO® associados à solução glicólica de Aloe vera a 2%. Após o estabelecimento da proporção pó/líquido para cada cimento, foram analisadas as propriedaes físicoquímicas: tempo de endurecimento, alteração dimensional, pH e radiopacidade. Cinco amostras de cada cimento foram usadas para cada teste, seguindo a especificação n. 57 da American National Standards Institute/American Dental Association (ANSI/ADA). A análise estatística foi realizada usando ANOVA e o teste de Tukey em nível de significância de 5%. Quando a distribuição das amostras foi não normal, a análise de variância não paramétrica foi realizada com o teste de Kruskal-Wallis (α=0,05). Os resultados não mostraram diferenças estatisticamente significantes (p>0,05) entre os cimentos em relação à proporção pó/líquido, que variou de 3,14 a 3,52 gramas. O ProRoot MTA® apresentou o tempo de endurecimento mais longo (116,50 min) e o MTA BIO® o menor (66,75 min) (p<0,05). Os cimentos Portland brancos estrutural e não estrutural apresentaram valores médios de solubilidade mais elevados (2,30 e 2,81%, respectivamente) (p<0,05). Todos os cimentos testados apresentaram valores de alteração dimensional semelhantes entre si (1,00%). O pH dos cimentos manteve-se elevado do início ao final do experimento, não havendo diferenças significantes entre os valores médios obtidos (cimento Portland branco estrutural, 11,96; cimento Portland branco não estrutural, 11,80; MTA BIO® 12,07; ProRoot MTA® 11,77) (p>0,05). Os cimentos Portland branco estrutural e não estrutural não apresentaram valores médios em conformidade com ANSI/ADA no teste de radiopacidade (109,76 e 118,75 mmAl, respectivamente), significantemente diferentes dos cimentos MTA BIO® (156,83 mmAl) e ProRoot MTA® (157,95 mmAl) (p<0,05), que apresentaram valores de densidade radiográfica acima do degrau 3 do penetrômetro de alumínio. O MTA BIO® evidenciou menor tempo de endurecimento e menor percentual de solubilidade. Nenhum cimento apresentou solubilidade maior que 3%. Todos os xiv cimentos analisados mostraram valores aceitáveis de alteração dimensional e pH elevado durante todo o período de teste. O MTA BIO® e o ProRoot MTA® apresentaram valores de radiopacidade adequados..
66

Estudo da evolução tumoral, caquexia e metástase em diferentes modelos animais in vivo e in vitro = Tumour growth, cachexia and metastasis in vivo and in vitro / Tumour growth, cachexia and metastasis in vivo and in vitro

Tomasin, Rebeka, 1985- 26 August 2018 (has links)
Orientador: Maria Cristina Cintra Gomes Marcondes / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T00:25:10Z (GMT). No. of bitstreams: 1 Tomasin_Rebeka_D.pdf: 4368331 bytes, checksum: 33a1f49902e0d1a423b1a4b7ebe757e9 (MD5) Previous issue date: 2014 / Resumo: Câncer é um nome genérico para um grupo de mais de cem doenças que compartilham algumas características. Talvez a característica mais marcante das neoplasias malignas seja a rápida proliferação de células anormais para além de suas fronteiras usuais, invasão de tecidos adjacentes e finalmente dispersão para órgãos distantes. Anualmente, cerca de oito milhões de pessoas morrem devido ao câncer e outros doze milhões de novos casos são diagnosticados. Dentre os eventos associados à progressão neoplásica, destacam-se as metástases e a caquexia. Metástases são tumores em sítios secundários, sendo responsáveis por cerca de 90% do total de mortes por câncer. Já a caquexia, uma síndrome paraneoplásica, é caracterizada por extensa espoliação de gordura e massa magra, fadiga e alterações metabólicas, prejudicando a qualidade de vida e a sobrevida de cerca de 50-85% dos pacientes, dependendo do tipo de tumor. Com relação às terapias, o grande desafio ainda é combater o tumor sem prejudicar o hospedeiro, o que acredita-se ser possível através de terapias-alvo para genes específicos e/ou tratamentos coadjuvantes, incluindo aqueles que empregam suplementação e/ou drogas derivadas de produtos naturais, que muitas vezes tem menor efeito tóxico ao hospedeiro. Desse modo, este trabalho teve dois objetivos: (1) avaliar a ação da administração oral de Aloe vera e mel sobre o tecido tumoral e o hospedeiro portador de carcinosarcoma de Walker 256; e (2) identificação de genes supressores de metástase através de screen funcional in vivo empregando-se biblioteca de shRNA em modelo de câncer de mama triplo negativo. Em relação ao primeiro objetivo, os resultados sugerem que a associação entre Aloe vera e mel pode modular a proteólise e o estresse oxidativo de maneira diferencial preservando o hospedeiro em detrimento do tecido tumoral. Ainda, o tratamento com Aloe vera e mel parece ser capaz de diminuir a propensão metastática das células tumorais in vivo, através de aumento na expressão de caderina-E e redução na expressão de caderina-N, bem como inibição da angiogênese. Outros experimentos sugerem que os efeitos antitumorais observados in vivo estão, em parte, relacionados à ação imunomodulatória de alguns componentes da Aloe vera. Com relação ao segundo objetivo, foram identificados dezenas de candidatos a genes supressores de metástase. Dentre esses genes, que estão sendo validados, Mnat1, Snd1, Cul5, Gabbr1, Rorb, Adk, Ccnd3, Gdnf, Nr1d1, Ptprs e Ltah4 são os genes-candidatos de maior confiabilidade por cumprirem um ou mais dos seguintes requisitos: (a) diminuição significativa do nível de DNA e RNA em canceres de mama humanos agressivos, sendo assim relacionados à pior prognostico, (b) papel biológico sugestivo, (c) fenótipo marcante durante o screen ou ainda (d) decréscimo significativo na expressão em linhagens de câncer de mama mais agressivas / Abstract: Cancer is a generic name for a group of over a hundred diseases which share some features. The most remarkable feature in cancer disease is the fast proliferation of abnormal cells beyond their usual boundaries, invasion of surrounding tissues and finally spread to distant organs. Every year, cancer is responsible for over eight million deaths and twelve million new cases are diagnosed. Among all the events associated with the neoplastic progression, metastasis and cachexia are major issues. Metastases, which are tumours growing in secondary sites, account for 90% of all cancer deaths. Cachexia, a paraneoplastic syndrome, is characterized by severe fat and lean mass waste, fatigue and metabolic alterations, jeopardizing the quality of life and reducing the survival of about 50-85% of the cancer patients, depending on the tumour type. Regarding to the therapies, the biggest challenge is still fighting the tumour without harming the host, which is believed to be possible by targeted therapies to specific genes and/or adjuvant treatments, including supplementation and drugs derived from natural compounds, which usually have lower side effects in the host. Knowing these points, this work had two aims: (1) evaluate the effects of Aloe vera and honey in both tumour and host tissues in Walker 256-tumour bearing rats; and, (2) identification of metastasis suppressor genes using a functional in vivo shRNA screen in a triple negative breast cancer syngeneic model. Regarding to the first aim, the results suggested that the combination of Aloe vera and honey selectively modulate proteolysis and oxidative stress, damaging the tumour tissue while protected the host. Moreover, the Aloe vera and honey treatment apparently decreases the metastatic potential in vivo, by simultaneous increase in E-cadherin and decrease in N-cadherin expression, while decreased tumour vascularization. Finally, our results suggested the antitumoral effects observed in vivo are, at least partially, related to the immunomodulatory activity of some Aloe vera¿s compounds. Regarding to the second aim, dozens of putative metastasis suppressor genes were identified. High confidence candidates, which would be further analysed are Mnat1, Snd1, Cul5, Gabbr1, Rorb, Adk, Ccnd3, Gdnf, Nr1d1, Ptprs e Ltah4. Their selection was based on meeting the following requirements: (a) significant decrease at DNA or RNA level in highly aggressive human breast cancer carcinomas and thus, worse prognosis, (b) suggestive biological role, (c) occurrence of a remarkable phenotype during the screen, and (d) significant decrease in expression in more aggressive cancer cell lines / Doutorado / Biologia Celular / Doutora em Biologia Celular e Estrutural
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Efeito antinociceptivo, antiinflamatório e antioxidante da Aloe saponaria Haw em modelos de queimadura em ratos / Antinociceptive, anti-inflammatory and antioxidant effects of Aloe saponaria Haw in a model of burn in rats

Silva, Mariane Arnoldi da 19 December 2013 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / In Brazil, the plant Aloe saponaria Haw, popularly known as babosa pintadinha , has been empirically used for its potential effect on skin burn injury, there are no scientific data confirming its popular use. Thus, the aim of the present study was to investigate the effects of Aloe saponaria on nociceptive, inflammatory and antioxidants parameters in rat models of thermal injury. Adult male Wistar rats were subjected to a thermal injury (immersion in water at 70 or 37 ºC, respectively, for 5 or 8 seconds) or sunburn (induced by UVB irradiation), in both experiments the animals were anesthetized. Burned animals were topically treated with vehicle (base cream), sulfadiazine 1% (positive control) or Aloe saponaria cream (0.3-30%) once a day for 2 or 6 days. Each day, 30 min before the treatment, we measured nociceptive (static and dynamic mechanical allodynia, thermal allodynia and spontaneous pain), inflammatory (paw edema) parameters and oxidative stress (increases in H2O2, protein carbonyl levels and lipid peroxidation and a decrease in thiol content). In addition, was also evaluated infiltration of leukocytes in injured tissue (for histology or by measuring the activity of myeloperoxidase (MPO), N - acetyl - glucosaminidase (NAGase) and eosinoperoxidase (EPO), for neutrophils, macrophages, and eosinophils infiltration, respectively), were also determined 2 or 6 days after the thermal injury. With different efficacies time of action, the topical treatment with the Aloe saponaria cream (10%) and sulfadiazine (1%) decreased nociception, edema and leukocyte infiltration in animals induced by either thermal injury scald burn), or by UVB radiation. Moreover, the treatment with A. saponaria reduced the oxidative stress of the skin of animals irradiated with UVB, an effect that appears to be due to the antioxidant action produced by both the extract of A. saponaria, and by some of these constituents (rutin and aloin). Thus, our results demonstrate that topical application of A. saponaria showed antinociceptive, anti-inflammatory and antioxidant models of thermal injury (scald burn or solar radiation), which confirms the benefits of its traditional use for burn injuries effects. / Apesar da planta Aloe saponaria Haw, conhecida popularmente como "babosa pintadinha", ser utilizada na medicina popular brasileira devido ao seu efeito benéfico sobre lesões por queimaduras de pele, não existem dados científicos que confirmem o seu uso popular. Dessa forma o objetivo do presente estudo foi investigar os efeitos da A. saponaria em relação aos parâmetros nociceptivos, inflamatórios e oxidantes em modelos de lesão térmica em ratos. Para isso foram utilizados ratos Wistar machos adultos submetidos ou não à lesão térmica (causada pela imersão da pata em água a 37 ou 70 ºC durante 8 ou 5 segundos em animais anestesiados) ou queimaduras solares (induzida por radiação ultravioleta B (UVB) em animais anestesiados). Os animais foram topicamente tratados com o veículo (creme base - Lanete), sulfadiazina de 1% (controle positivo) ou com extrato de A. saponaria (0,3-30%) uma vez por dia, durante 2 ou 6 dias. Cada dia, 30 minutos antes do próximo tratamento, foram avaliados parâmetros nociceptivos (alodínia mecânica estática e dinâmica, alodínia térmica e dor espontânea), parâmetros inflamatórios (edema da pata) e estresse oxidativo (aumento dos níveis de peróxido de hidrogênio-H2O2, proteína carbonilada ou peroxidação lipídica e redução dos níveis de tióis). Além disso, em alguns tempos após os diferentes estímulos também foi avaliado a infiltração de leucócitos no tecido lesado (por análise histológica ou pela medida das atividades da mieloperoxidase - MPO, N-acetil-glucosaminidase - NAGase e eosinoperoxidase - EPO para neutrófilos, macrófagos e eosinófilos, respectivamente). Com diferentes eficácias temporais de ação, o tratamento tópico com o creme de Aloe saponaria (10%) ou de sulfadiazina (1%) reduziu a nocicepção, o edema e a infiltração de leucócitos nos animais com lesão térmica induzida tanto por água aquecida, quanto por radiação UVB. Além disso, o tratamento com A. saponaria reduziu o estresse oxidativo da pele de animais irradiada com UVB, um efeito que parece ser devido a ação antioxidante produzida tanto pelo extrato de A. saponaria, quanto por alguns de seus constituintes (aloína e rutina). Dessa forma, os nossos resultados demonstram que a aplicação tópica de A. saponaria apresentou efeitos antinociceptivos, antiinflamatórios e antioxidantes em modelos de lesão térmica (água aquecida ou radiação solar), o que confirma os benefícios do seu uso tradicional para lesões por queimaduras.
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Dihydroisocoumarins, Naphthalenes, and Further Polyketides from Aloe vera and A. plicatilis: Isolation, Identification and Their 5-LOX/COX-1 Inhibiting Potency

Rauwald, Hans Wilhelm, Maucher, Ralf, Dannhardt, Gerd, Kuchta, Kenny 05 May 2023 (has links)
The present study aims at the isolation and identification of diverse phenolic polyketides from Aloe vera (L.) Burm.f. and Aloe plicatilis (L.) Miller and includes their 5-LOX/COX-1 inhibiting potency. After initial Sephadex-LH20 gel filtration and combined silica gel 60- and RP18-CC, three dihydroisocoumarins (nonaketides), four 5-methyl-8-C-glucosylchromones (heptaketides) from A. vera, and two hexaketide-naphthalenes from A. plicatilis have been isolated by means of HSCCC. The structures of all polyketides were elucidated by ESI-MS and 2D 1H/13C-NMR (HMQC, HMBC) techniques. The analytical/preparative separation of 3R-feralolide, 3′-O-β-d-glucopyranosyl- and the new 6-O-β-d-glucopyranosyl-3R-feralolide into their respective positional isomers are described here for the first time, including the assignment of the 3R-configuration in all feralolides by comparative CD spectroscopy. The chromones 7-O-methyl-aloesin and 7-O-methyl-aloeresin A were isolated for the first time from A. vera, together with the previously described aloesin (syn. aloeresin B) and aloeresin D. Furthermore, the new 5,6,7,8-tetrahydro-1-O-β-d-glucopyranosyl- 3,6R-dihydroxy-8R-methylnaphtalene was isolated from A. plicatilis, together with the known plicataloside. Subsequently, biological-pharmacological screening was performed to identify Aloe polyketides with anti-inflammatory potential in vitro. In addition to the above constituents, the anthranoids (octaketides) aloe emodin, aloin, 6′-(E)-p-coumaroyl-aloin A and B, and 6′-(E)-p-coumaroyl-7-hydroxy-8-O-methyl-aloin A and B were tested. In the COX-1 examination, only feralolide (10 µM) inhibited the formation of MDA by 24%, whereas the other polyketides did not display any inhibition at all. In the 5-LOX-test, all aloin-type anthranoids (10 µM) inhibited the formation of LTB4 by about 25–41%. Aloesin also displayed 10% inhibition at 10 µM in this in vitro setup, while the other chromones and naphthalenes did not display any activity. The present study, therefore, demonstrates the importance of low molecular phenolic polyketides for the known overall anti-inflammatory activity of Aloe vera preparations.
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AVALIAÇÃO DO EFEITO CICATRIZANTE DE FILMES DE ALGINATO CONTENDO GEL DE BABOSA - Aloe vera (L.) Burm. f. / Avaliação do efeito cicatrizante de filmes de alginato contendo gel de babosa Aloe vera (L.) Burmx

Koga, Adriana Yuriko 23 February 2017 (has links)
Made available in DSpace on 2017-07-21T14:35:57Z (GMT). No. of bitstreams: 1 ADRIANA YURIKO KOGA.pdf: 2085290 bytes, checksum: 04ba643fa625913ec2b768408faac0ab (MD5) Previous issue date: 2017-02-23 / Alginate is a polymer extracted from seaweed and traditionally used in various types of wound dressings. It is a polysaccharide which has bioadhesive and swelling characteristics. The ability of alginate to form gel and films provides a favorable environment for healing and re-epithelialization of the injured tissue. Aloe vera (L.) Burm. f., or simply Aloe, is a medicinal plant with analgesic, anti-inflammatory and healing properties. The purpose of this study was to develop an alginate film containing Aloe gel and examine its cutaneous healing effect in vivo. The film was obtained by casting of the aqueous sodium alginate solution containing glycerin and Aloe gel, followed by crosslinking with calcium chloride. The film was characterized by mechanical tensile strength, hydration degree, FTIR spectroscopy, scanning electron microscopy, polysaccharide and calcium release. The wound healing effect was studied by performing surgical wounds in the back of Wistar rats. The animals (n = 60) were divided into three groups: gauze dressings (control), dressing with alginate film and dressing with alginate-aloe film. The retraction of wounds was measured every 3 days. On days 3, 7, 14, 22 five animals from each group were euthanized and samples of skin were removed and fixed in formalin 10%. The samples for histological analysis were stained with hematoxylin-eosin and analyzed for quantification of inflammatory infiltrate, angiogenesis and macrophages. Collagen fibers were evaluated using a picrosirius red staining for differentiation of type I and III fibers. The alginate-aloe film exhibited desirable physical and mechanical characteristics for the wound dressing application. In vivo animal test revealed there was no significant difference among the three groups in wound retraction. The results of histological analysis showed a beneficial effects of alginate-aloe (p=0.04) and alginate films (p=0.05) decreasing the inflammatory infiltrate at 14th days, in relation to the control group. On the 7th day, there was an increased angiogenesis in the control group compared to the group treated with alginate-aloe films (p = 0.04) and alginate (p = 0.024). Treatment with alginate-aloe film increased the number of blood vessels on the 14th day, when compared to the control group (p = 0.004); in addition, it caused decrease of macrophages on day 22, when compared to the other groups (alginate film (p = 0,0) and control (p = 0.007). The evaluation of the collagen fibers showed a significant difference between the alginate-aloe film and control group, with evident decrease of type III fibers (p = 0.05) and increase of type I fibers (p = 0.024) between days 14 and 22, suggesting an improvement in the progression of the healing process. / O alginato é um polímero extraído de algas marinhas e tradicionalmente utilizado na fabricação de curativos. A propriedade de formar géis e filmes faz com que o alginato proporcione um ambiente favorável à cicatrização e a re-epitelização do tecido lesado. Aloe vera (L.) Burm. f., popularmente conhecida como babosa, é uma planta medicinal que apresenta propriedades analgésica, anti-inflamatória e cicatrizante. O objetivo deste trabalho foi desenvolver um filme de alginato contendo gel de babosa e avaliar o seu efeito cicatrizante in vivo. O filme foi obtido por evaporação de uma solução aquosa de alginato de sódio contendo glicerina, gel de babosa e reticulado com cloreto de cálcio. O filme foi caracterizado por ensaios de resistência mecânica a tração, hidratação, espectroscopia no infravermelho (FTIR), microscopia eletrônica de varredura e liberação de polissacarídeos e íons cálcio. Na avaliação do efeito cicatrizante, foi utilizado o modelo de lesão cirúrgica na pele da região cérvico-lombar de ratos Wistar. Os animais (n=60) foram divididos em três grupos: curativos com gaze (controle), curativos com filme de alginato e curativos com filme alginato-babosa. As medidas da retração das feridas foram realizadas a cada 3 dias. Nos dias 3, 7, 14 e 22 cinco animais de cada grupo foram eutanasiados e um fragmento de pele foi retirado e fixado em formol 10%. As análises histológicas dos tecidos foram realizadas utilizando-se coloração hematoxilina eosina para quantificação de infiltrado inflamatório, avaliação da angiogênese e contagem de macrófagos. As fibras colágenas foram avaliadas utilizando a coloração picrosirius red para diferenciação das fibras de tipo I e III. As análises físico-químicas do filme evidenciaram características ideais para a aplicação como curativos. No ensaio do efeito cicatrizante, não houve diferença significativa entre os grupos na avaliação da retração da lesão. Os resultados das análises histológicas mostraram uma diminuição do infiltrado inflamatório com os filmes alginato-babosa (p=0,04) e alginato (p=0,05) no 140 dia, em relação ao grupo controle. No 70 dia, observou-se uma maior angiogênese no grupo controle comparado aos grupos filme alginato-babosa (p=0,04) e alginato (p=0,024). O tratamento com o filme alginato-babosa aumentou o número de vasos sanguíneos no dia 14, quando comparado ao grupo controle (p=0,004); além disso, ocasionou uma diminuição mais expressiva de macrófagos no dia 22, quando comparado aos demais grupos (filme alginato (p=0,0) e controle (p=0,007)). A avaliação das fibras colágenas mostrou uma diferença significativa entre os grupos filme alginato-babosa e controle, com evidente diminuição das fibras tipo III (p=0,05) e aumento das fibras tipo I (p=0,024) entre os dias 14 e 22, sugerindo uma melhora na progressão do processo de cicatrização.
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Naturstoffe aus Zell- und Wurzelkulturen von Triphyophyllum peltatum, Experimente zur Biosynthese der Naphthylisochinolin-Alkaloide sowie Kalluskulturen und Sekundärmetabolite aus Aloe saponaria / Natural products from cell and root cultures of Triphyophyllum peltatum, experiments on the biosynthesis of naphthyl isoquinoline alkaloids and callus cultures and secondary metobolites from Aloe saponaria

Irmer, Andreas January 2012 (has links) (PDF)
Beschrieben ist die Isolierung und Strukturaufklärung von Naturstoffen (Naphthochinone, dimere Naphthaline und Naphthylisochinolin-Alkaloide) aus Zell- und Wurzelkulturen von Triphyophyllum peltatum. Darüber hinaus wurden Experimente zur Biosynthese der Naphthylisochinolin-Alkaloide mit 13C2-markierten Vorstufen durchgeführt. Ebenso Bestandteil der Arbeit war die Etablierung von Kalluskulturen von Aloe saponaria, aus der ebenfalls Sekundärmetabolite isoliert wurden. / The isolation and structure elucidation of natural products (naphthoquinones, dimeric naphthalenes and naphthyl isoquinoline alkaloids) from cell and root cultures of Triphyophyllum peltatum is described. Furthermore, experiments on the biosyntheses of the naphthyl isoquinoline alkaloids using 13C2 labeled precursors are reported. Additionally, callus cultures of Aloe saponaria were established and secondary metabolites were isolated.

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