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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.
71

Aloe leaf materials as excipients for controlled release multiple unit drug delivery systems

Jambwa, Nyasha Tafara. January 2011 (has links)
M. Tech. Pharmaceutical Sciences. / Investigates the potential of A. ferox and A. vera gel and whole leaf extract materials alone or in combination with Carbopol® 971P NF and HPMC as excipients in a multi-unit controlled release matrix type system.
72

Micropropagation and acclimatization of Aloe polyphylla and Platycerium bifurcatum.

Chukwujekwu, Jude Chinedu. 11 December 2013 (has links)
Shoot cultures of Aloe polyphylla were initiated from young shoot explants of in vitro grown plants. The basal medium was MS medium (MURASHIGE and SKOOG, 1962), supplemented with 100 mgl ¯¹ myo-inositol, and 30 gl ¯¹ sucrose. Agar (0.8 %) was used as the gelling agent. Different cytokinins, singly or in combination with auxins (IBA and NAA), were tested for shoot proliferation activity. All the cytokinins tested (kinetin, zeatin, iP, and BA) gave a good shoot proliferation response. The optimal concentrations for shoot proliferation of each of the cytokinins tested were: zeatin (0.5 mgl ¯¹), kinetin (1.5 mgl ¯¹), iP (1.0 mg ¯¹) and BA (1.5 mgl ¯¹). In combination with auxins, the optimal combinations were kinetin/NAA (2.0/0.1 mgl ¯¹), kinetin/lBA (1.5/1.0 mgl ¯¹), zeatin/lBA (1.0/0.5 mgl ¯¹), zeatin/NAA (1.0/1.0 mgl ¯¹), BA/IBA (1.0/1.0 mgl ¯¹), BA/NAA (1.5/0.1 mgl ¯¹). Although it gave the highest number of shoots per explant, BA was responsible for hyperhydricity. Temperature and sucrose also influenced shoot proliferation. The optimal temperature was 25°C, while 30 gl ¯¹ was the optimal concentration of sucrose for shoot proliferation. Plants rooted well in plant growth regulator-free MS medium. Amongst the potting mixtures tested, soil: sand: vermiculite (1:1:1 v/v) was the best with 98 % plantlet survival. In the second part of this project, Platycerium bifurcatum cultures were established using leaf explants. The basal medium was MS medium (MURASHIGE and SKOOG, 1962), supplemented with 100 mgl ¯¹ myo-inositol and 30 g l ¯¹ sucrose. For bud initiation, 1.0 mgl ¯¹ BA was used, while 0.8 % agar was used as the gelling agent. Three different strengths of MS medium (full, half, and one-quarter strength) without plant growth regulators were tested for further bud growth and development. Half-strength MS proved to be the best for further bud growth and development. Rooting was best achieved in one-quarter strength MS medium without plant growth regulators. In vitro grown plantlets were successfully acclimatized using peat as the potting medium. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2001.
73

Characterization and control of micropropagation problems in aloe, devil's claw and banana.

Bairu, Michael Wolday. January 2008 (has links)
The development of the science of micropropagation from the very initial concept of totipotency to the modern day advancement and sophistication has been affected by a wide range of problems such as hyperhydricity, shoot-tip necrosis and somaclonal variation. These problems are largely the result of the obvious fact of trying to grow plants in an environment that is different from the one plants are used to naturally. The extent of these problems ranges from minor technical inconvenience to significant economic loss. Characterization and control of micropropagation problems has been one of the priorities of plant tissue culture research due to the enormous contribution of this discipline for plant production, improvement and conservation. The prevalence and severity of these tissue culture problems varies widely among plant species. The rationale of this research project was therefore, to identify plant species most affected by the problems studied, characterize the problem and find mechanism(s) to control or minimize the damage caused by the problem. The literatures reviewed provide sufficient background information for the experimental chapters. Due to the different nature of the problems and variation in the plant species they affect, the model plant, the methodologies used and parameters analysed were also different. The findings of these investigations, in their own different way, addressed certain problems that individually and collectively pose difficulties to the micropropagation industry. The difference in the content of the experimental chapters is therefore the result of the broader objective of the research project to tackle such difficulties. The success and failure of tissue culture system greatly depends on the choice of PGR’s. This choice can be made based on comparative study of their biological activity. Some promising reports on the role of topolins in micropropagation led to the idea of testing these cytokinins for their potential in tissue culture. As a prerequisite to subsequent investigations, the biological activity of some selected topolins and BA derivatives was tested using the soybean callus bioassay. The activity of the cytokinins tested varied significantly. The results demonstrated that the structure of a cytokinin dictates its activity. Modifications of side-chain improved the activity of oT but had no effect on pT. The presence of the methyl group had an enhancing effect on cytokinin activity of topolins or at least it did not reduce it. BA derivatives BA9THP (conjugated at N9 position), 3FBA and 2Cl6(3OHBA)R (halogenated derivatives) also showed good cytokinin activity and hold good promise for future research. In an attempt to alleviate hyperhydricity in Aloe polyphylla and optimize the micropropagation protocol, meta-topolin and its derivatives were tested at various concentrations together with BA and zeatin. Of all the cytokinins tested mT produced the best results in terms of shoot and root growth. Five μM was found to be the optimum concentration at which complete control of hyperhydricity was achieved without compromising shoot and root growth. Plantlets rooted in a multiplication media. BA generally had a negative effect on growth and development both in vitro and ex vitro. Acclimatization of plantlets was achieved easily by initially transferring plantlets to a mist house (for three weeks) followed by transfer to the greenhouse. The type of cytokinin also had an effect on ex vitro growth with BA-treated plants producing the lowest shoot and root biomass. Various experiments were conducted to characterize and control factors affecting STN in Harpagophytum procumbens. Media type and strength, PGR, carbon sources, sub-culturing, calcium and boron were tested. Results indicated that all of the tissue culture components tested affected STN. From the different media types tested, half strength was MS found to be the preferred medium. Increasing cytokinin concentration increased the incidence of STN and the problem was aggravated by the addition of auxin to the multiplication medium. Optimum shoot multiplication was achieved by omitting auxin and using the cytokinin mTR. Plantlets produced basal callus which interfered with rooting. The quantity of this basal callus was minimum when mTR was used. Sub-culturing plantlets onto fresh medium every two weeks helped minimize STN. Off all the sugars tested 3% sucrose was optimum. Other sugars either aggravated STN or inhibited growth when compared at equi-molar concentration. Increasing the concentration of either Ca or B prevented the development of necrotic shoots. When the concentration of both elements is increased simultaneously negative effects on both growth and STN were observed. Using 6 mM Ca in half strength MS medium was optimum. B was toxic at higher concentrations. Plantlets rooted readily in half strength cytokinin-free MS media supplemented with 2.5 μM IAA. Rooted plantlets produced using the optimized protocol were acclimatized successfully by transferring directly to a greenhouse in a 1:1 ratio of sand and soil mixture. The effect of meta-toplins on micropropagation and somaclonal variation of banana was investigated. Tissue cultured explants of cultivars ‘Williams’ and ‘Grand Naine’ were cultured in MS media containing the cytokinins BA, mT, MemT, MemTR and mTR at various concentrations. Results of the investigation revealed that superior multiplication and lower abnormality index was recorded from the mTR and mT treatments at 22.2 μM concentration. These treatments, however, had an inhibitory effect on rooting. The effect of these treatments (22.2 μM mT and mTR) in comparison with equi-molar concentration of BA on somaclonal variation of ‘Williams’ banana was tested using RAPD-PCR at the 7th multiplication cycle. No significant difference was found between the treatments. It should however be highlighted that cultures were initially maintained for three multiplication cycles in media containing BA. The inherent stability and initial effect of BA could have influenced the results. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
74

The phytochemical content and anti-diabetic properties of Aloe ferox and Aloe greatheadii var. davyana / Lisa Botes

Botes, Lisa January 2009 (has links)
Thesis (Ph.D. (Dietetics))--North-West University, Potchefstroom Campus, 2010.
75

The phytochemical content and anti-diabetic properties of Aloe ferox and Aloe greatheadii var. davyana / Lisa Botes

Botes, Lisa January 2009 (has links)
Thesis (Ph.D. (Dietetics))--North-West University, Potchefstroom Campus, 2010.
76

Caracterização físico-química e estrutural de polissacarídeos obtidos de folhas da planta Aloe barbadensis Miller e avaliação de suas atividades antiviral e anti-hemorrágica / Physico-chemical characterization and structural polysaccharides obtained from leaves of the plant Aloe barbadensis Miller and evaluation of their activities antiviral and anti-haemorrhagic

Eloy, Ygor Raphael Gomes January 2012 (has links)
ELOY, Ygor Raphael Gomes. Caracterização físico-química e estrutural de polissacarídeos obtidos de folhas da planta Aloe barbadensis Miller e avaliação de suas atividades antiviral e anti-hemorrágica. 2012. 186 f. Tese (Doutorado em bioquímica)- Universidade Federal do Ceará, Fortaleza-CE, 2012. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-28T15:19:36Z No. of bitstreams: 1 2012_tese_yrgeloy.pdf: 4816746 bytes, checksum: df9405e734ec6c678912a942f68c57ad (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-08-02T14:43:54Z (GMT) No. of bitstreams: 1 2012_tese_yrgeloy.pdf: 4816746 bytes, checksum: df9405e734ec6c678912a942f68c57ad (MD5) / Made available in DSpace on 2016-08-02T14:43:54Z (GMT). No. of bitstreams: 1 2012_tese_yrgeloy.pdf: 4816746 bytes, checksum: df9405e734ec6c678912a942f68c57ad (MD5) Previous issue date: 2012 / 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 °C) 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 â-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. / Este trabalho teve como objetivos caracterizar físico-química e estruturalmente polissacarídeos obtidos de folhas de Aloe barbadensis e avaliar suas atividades antiviral, anti-hemorrágica e pró-coagulante e possíveis sinais de toxicidade. Foi realizada extração aquosa de polissacarídeos totais (PT) de A. barbadensis, seguido de precipitação por etanol e remoção dos contaminantes proteicos com TCA. A cromatografia em DEAE-celulose foi eficiente no fracionamento dos PT, onde foram obtidas as frações PI e PII. A caracterização físico-química mostrou que a fração PI é composta por manose (78,4%), glucose (7,3%), galactose (2,1%), fucose (2,8%) e ácidos urônicos (10,0%), e isenta de grupos éster sulfato. Enquanto, a fração PII é constituída por manose (39,2%), glucose (22,2%), galactose (26,3%), arabinose (3,8%), xilose (1,1%), ácidos urônicos (8,0%) e grupos éster sulfato (12,0%). Na revelação das bandas polissacarídicas da fração PII, obtidas por PAGE e gel de agarose corados com stainsall foi constatado a presença de duas bandas que apresentaram diferentes colorações, roxa e ciana, correspondentes a presença de grupos sulfato e carboxilados, respectivamente. Na análise estrutural das frações PI e PII, por espectroscopia no IR, foi demonstrado que a fração PI apresenta unidades monossacarídicas de â-manose O-acetiladas (812,2 e 960 onda.cm-1) e ácidos urônicos neutros (1738 onda.cm-1) em sua estrutura. Diferentemente, a fração PII, mostrou-se ser constituída por unidades monossacarídicas de manose (1014,7 onda.cm-1), galactose (1078,2 onda.cm-1), ácidos urônicos carregados negativamente (1635 onda.cm-1) e éster sulfato (1329,5 e 1260,9 onda.cm-1). Na avaliação estrutural da fração PII por RMN foi comprovado à presença do grupo éster sulfato. Em relação às atividades biológicas, o teste de citotoxicidade mostrou que os PT e as frações PI e PII não apresentaram toxicidade para a maioria das células testadas e não foram eficientes na inibição de vírus não envelopados Ad-19 e Ad-41. No entanto, os PT e a fração PI foram capazes de inibir a infecção causada por HSV-1 e HSV-2. Em ensaios com metapneumovírus (HMPV), a fração PII apresentou atividade antiviral superior à ribavirina. Embora os PT e as frações PI e PII não terem apresentado atividade contra dengue vírus 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 baço e o número de plaquetas sanguíneas. Pode ser concluído que extratos foliares de A. barbadensis podem apresentar polissacarídeos neutros ou carregados negativamente por grupos carboxilados/sulfatados. Em adição, além de apresentar atividade inibitória contra os vírus HSV-1, HSV-2 e HMPV, podem também apresentar efeito anti-hemorrágico e prócoagulante, propriedades essas, importantes, visto que a complicação de muitas viroses leva a quadros hemorrágicos. Além disso, os PT de A. barbadensis não apresentaram toxicidade expressiva, podendo ser utilizada como agente terapêutico seguro e eficaz.
77

Efeito de extratos vegetais na parasitemia do Trypanosoma cruzi e na biodistribui??o do pertecnetato de s?dio (Na99mTcO4)

Silva, Roseane Pereira da 14 December 2009 (has links)
Made available in DSpace on 2014-12-17T14:13:45Z (GMT). No. of bitstreams: 1 RoseanePS_Dissert.pdf: 3732658 bytes, checksum: 742911363ad84dd9ebc1a2c58e9d1d3f (MD5) Previous issue date: 2009-12-14 / Artemisia vulgaris (AV) is an antihelmintic and antimalarial drug; Aloe vera(babosa) acts as antidiabetic, laxative and anti-inflammatory; Benznidazole (BZ) is a trypanocidal of Trypanosoma cruzi (TC). Technetium-99m (99mTc) has been used in nuclear medicine to obtain diagnostic images. This study evaluated the plant effects in TC parasitemia and in the biodistribution of 99mTc in mice. Twenty mice were infected by TC. At the peak of parasitemia, 5 mice received babosa; 5 received AV and 5 received BZ. The parasitemia was determined in 0, 2, 4 and 6 h of drugs administration. Five infected mice without drugs, 5 mice without TC and the group treated with AV, received 99mTc. The radioactivity was calculated. Infected mice that received babosa reduced significantly (p<0.05) the parasitemia. The percentage of activity (%ATI) decreased significantly in the AV group. These results indicate that babosa possibly is an anti-TC drug and AV reduces the %ATI probably due to its biological effects / Artemisia vulgaris (AV) ? um vegetal com propriedades antihelm?ntica e antimal?rica; Aloe vera (babosa) tem ??o antidiab?tica, laxante e anti-inflamat?ria; Benzonidazol (BZ) ? um tripanomicida. O tecn?cio-99m (99mTc), na forma de pertecnetato de s?dio (Na99mTcO4), tem sido usado na medicina nuclear para obten??o de imagens diagn?sticas. Este estudo avaliou o efeito de plantas na parasitemia do T. cruzi e na biodistribui??o do 99mTc em camundongos. Vinte camundongos foram infectados por T. cruzi. No pico da parasitemia, 5 camundongos foram tratados com extrato aquoso de babosa, 5 AV e 5 BZ. A parasitemia foi determinada durante os tempos 0, 2, 4 e 6 horas ap?s administra??o das drogas. Cinco camundongos infectados e que n?o receberam drogas, 5 camundongos n?o infectados e o grupo tratado com AV receberam Na99mTcO4. O percentual de Atividade Total Injetada nos ?rg?os (%ATI/g), correspondente ? energia gama emitida ou radioatividade, foi calculada no contador gama. Os camundongos infectados que receberam babosa reduziram significativamente (p<0,05) a parasitemia. A porcentagem da radiatividade total (%ATI/g) diminuiu significativamente no grupo tratado com AV. Estes resultados indicam que a babosa possivelmente ? uma droga anti-T. cruzi e a AV reduz a %ATI/g provavelmente devido seus efeitos biol?gicos. Este trabalho teve a participa??o de pesquisadores das ?reas de Parasitologia, Estat?stica, Cirurgia, Medicina Nuclear e An?lises Cl?nicas, atestando seu car?ter multidisciplinar
78

Avaliação toxicológica pré-clínica e atividade laxantede Aloe ferox Miller

Ribeiro Leite, Vanessa 31 January 2010 (has links)
Made available in DSpace on 2014-06-12T16:27:15Z (GMT). No. of bitstreams: 2 arquivo1193_1.pdf: 802111 bytes, checksum: 2138eacdcd88ad8c201968b734c5b81f (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Aloe ferox, Asphodelaceae, é uma planta que se desenvolve em terras com chuvas mais ou menos moderadas e secas e solos menos férteis; possui ampla distribuição em toda a África do Sul, tendo maior concentração nas Províncias do Cabo Leste e Oeste. No Brasil, esta planta é encontrada no interior de São Paulo, Santa Catarina e na região nordeste; sendo esta última a que possui melhores condições de cultivo. Aloe ferox é popularmente utilizada como laxante, porém existe uma carência de estudos referentes à eficácia de seu uso como laxante bem como de informações toxicológicas detalhadas sobre a espécie. Neste contexto, o trabalho teve como objetivo avaliar o efeito da resina de Aloe ferox Miller sobre o trânsito intestinal em ratos e investigar a segurança de seu uso. Para isso foram realizados o teste de motilidade intestinal em camundongos, nas doses de 0.05, 0.1 e 0.2 g/kg, teste de toxicidade aguda em ratos e avaliou-se a influência da administração crônica (13 semanas) por via oral do extrato da resina de Aloe ferox, nas doses de 0.1, 0.5 e 1.5 g/kg, sobre os parâmetros bioquímicos, hematológicos e morfológicos em ratos. Os resultados mostraram que na toxicidade aguda, Aloe ferox não produziu morte dos animais em doses de até 5 g/kg. Para a atividade laxante, observou-se que após 30 minutos da administração Aloe ferox aumentou a motilidade intestinal em camundongos em mais de 90% em todas as doses administradas. No entanto, a administração crônica promoveu alterações em vários parâmetros bioquímicos, hematológicos e morfológicos. No que se diz respeito aos parâmetros hematológicos, Aloe ferox, na dose de 1.5 g/kg induziu uma redução nos valores de eritrócitos, hematócrito e hemoglobina nos primeiros trinta dias de tratamento e aumento dos valores desses parâmetros no último mês de tratamento para ambos os sexos e promoveu o aumento do RDW em fêmeas tratadas com a mesma dose (1.5 g/kg). Com relação aos parâmetros bioquímicos, os animais tratados com Aloe ferox na dose de 1.5 g/kg sofreram uma redução nos níveis de creatinina e aumento de bilirrubina total e indireta em ambos os sexos. Nas fêmeas verificou-se uma redução nos níveis de HDL e triglicerídeos e aumento de bilirrubina direta. Os machos apresentaram aumento de fosfatase alcalina e ALT. A análise morfológica de vísceras, encéfalo e órgãos reprodutivos bem como a massa absoluta e relativa destes órgãos apresentou alterações nos animais que sobreviveram ao tratamento com Aloe ferox na dose de 1.5 g/kg. As principais alterações observadas foram massa absoluta e relativa diminuída do baço em fêmeas e do intestino nos machos. Os resultados encontrados nos levam a concluir que Aloe ferox é eficaz no tratamento da constipação intestinal, porém induz alterações significativas em vários parâmetros bioquímicos, hematológicos e morfológicos em ratos Wistar de ambos os sexos, indicando que a administração desta planta pode exercer efeito tóxico ao ser humano
79

Efeitos terapêuticos do homogeinado de Aloe vera e mel sobre o crescimento e atividade celular do carcinossarcomia de Walker 256 / Effects of Aloe vera and honey on tumor growth evolution in rats

Tomasin, Rebeka, 1985- 16 August 2018 (has links)
Orientador: Maria Cristina Cintra Gomes Marcondes / Dissertação (mestrado) - Universidade Estadual de Campinas,I nstituto de Bi9ologia / Made available in DSpace on 2018-08-16T07:02:19Z (GMT). No. of bitstreams: 1 Tomasin_Rebeka_M.pdf: 6922959 bytes, checksum: 859d99a4ec9c7b0f3a25f971d31f8645 (MD5) Previous issue date: 2010 / Resumo: O câncer é responsável pela morte de oito milhões de pessoas todos os anos, sendo que anualmente são diagnosticados mais de onze milhões de novos casos. O estudo de tratamentos alternativos e coadjuvantes é, portanto, de grande valia. Aventa-se que tanto Aloe vera quanto o mel contém efeitos anti-câncer. O objetivo deste trabalho foi verificar a ação do homogeneizado de Aloe vera e mel sobre o crescimento tumoral e caquexia em ratos Wistar portadores de carcinossarcoma de Walker 256. Visando avaliar o impacto da administração de Aloe vera e mel sobre a proliferação celular e apoptose no decorrer do desenvolvimento tumoral, foram coletados tecido hepático e tumoral de animais sacrificados após 7, 14 e 20 dias de implantação tumoral. As análises imunohistoquímicas de tumores provenientes de animais tratados com homogeneizado de Aloe vera e mel revelaram, ao longo do desenvolvimento tumoral, queda na taxa de proliferação celular (Ki-67) e aumento na susceptibilidade à apoptose (relação Bax/Bcl-2) além de menor peso relativo do tumor, quando comparados aos tumores de animais que receberam soro fisiológico. Paralelamente, a análise do tecido hepático desses animais mostrou queda na susceptibilidade à apoptose (relação Bax/Bcl-2) em relação aos animais que não foram tratados com Aloe vera e mel. A fim de se avaliar o efeito terapêutico do homogeneizado de Aloe vera e mel sobre parâmetros relacionados ao estresse oxidativo e à caquexia, ratos Wistar tratados ou não anteriormente à indução tumoral foram redistribuídos de forma a iniciar (CWA), interromper (AW), manter (AWA) ou não receber tratamento (CW) com Aloe vera e mel após a indução de tumor. Os animais foram monitorados quanto ao ganho de peso, consumo de dieta e peso calculado do tumor. Após 21 dias de evolução tumoral, as análises morfométricas associadas à quantificação de proteínas séricas, bem como avaliação de estresse oxidativo (envolvendo análise da atividade de catalase, superoxido dismutase, glutationa S tranferase e fostatase alcalina, além do teor de proteína e MDA), em órgãos como fígado, músculo e coração, sugerem que o tratamento com homogeneizado de Aloe vera e mel auxiliou na modulação do estresse oxidativo, espoliação e caquexia, especialmente quando administrado de forma terapêutica (CWA). Em contrapartida, foi observada tendência a estresse oxidativo bem como queda na atividade de enzimas antioxidantes no tecido tumoral, em animais tratados com Aloe vera e mel. Os dados obtidos sugerem que a administração de Aloe vera e mel preserva a integridade dos tecidos hospedeiros enquanto provoca detrimento do tecido tumoral / Abstract: Cancer is diagnosed in approximately 11 million people and is responsible for approximately 8 million deaths every year. Research in cancer control has shown the importance of co-adjuvant therapies. Aloe vera may reduce tumour mass and metastasis rates, while honey may inhibit tumour growth. This study verified the influence of Aloe vera and honey on tumour growth and cachexia in tumour-bearing rats. The influence of Aloe vera and honey on tumour growth evolution was assessed through tumour cell proliferation rate (Ki67-LI) and Bax/Bcl-2 ratio at 7, 14 and 20 days after the implant of Walker 256 carcinoma (sc) in adult rats. The effect of Aloe vera and honey against tumour growth was observed through a decrease in tumour cell proliferative rates and an increase in apoptosis susceptibility (Bax/Bcl-2 ratio) in tumours of treated group compared to untreated group. In contrast, it was observed a decrease in apoptosis susceptibility (Bax/Bcl-2 ratio) in livers of Aloe vera and honey-treated group, showing a possible protective effect in liver tissue. In order to elucidate the therapeutic effects of Aloe vera and honey solution on oxidative stress and cachexia development, Aloe vera and honey-treated and untreated rats before tumour induction were distributed into the following groups: tumour-bearing rats treated after tumour implant (CWA), treated before tumour implant (AW), treated before and after tumour implant (AWA) with Aloe vera and honey solution and untreated tumour-bearing rats (CW). After 21 days of tumour implant, morphometric analyses, serum proteins content and oxidative stress assays (catalase, superoxide dismutase, glutathione-Stransferase, alkaline phosphatase activities and protein and MDA content) were evaluated in liver, muscle and myocardium. The Aloe vera and honey treatment modulated oxidative stress, tissue wasting and cachexia, especially as therapeutic way (CWA). On the other hand, tumour of Aloe vera and honey-treated rats tended to increase oxidative stress and/or decrease antioxidant enzymes activities. These data suggested Aloe vera and honey treatment affected tumour and host in a different way, by preserving host tissues while promoted damages in tumour tissue / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular
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Abordagens terapÃuticas na mucosite oral experimental induzida por 5-Fluorouracil: papel dos extratos de Aloe barbadensis (Babosa) e de Myracrodruon urundeuva (Aroeira do sertÃo) / Protective effects of Aloe barbadensis and Myracrodruon urundeuva on experimental oral mucositis induced by 5-fluorouracil

Rosane Oliveira de Sant Ana 21 December 2006 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / INTRODUÃÃO: A mucosite oral (MO) à um efeito colateral frequente em pacientes sob tratamento oncolÃgico, em especial à quimioterapia (QT). Caracteriza-se por hiperemia, edema e Ãlceras em toda a cavidade oral e faringe. A importÃncia da MO à devido à dor, alteraÃÃes do paladar e infecÃÃes locais. Surge incapacidade de alimentar-se, ingerir lÃquidos, risco de infecÃÃes sistÃmicas, necessidade de interrupÃÃo da QT, necessidade de hospitalizaÃÃo, tornando o tratamento mÃrbido, dispendioso, doloroso e muitas vezes impossÃvel ou ineficaz. Ainda nÃo hà terapÃutica totalmente eficaz, com nÃvel de evidÃncia que torne a MO manejÃvel. OBJETIVOS: Avaliar os efeitos do tratamento tÃpico com duas plantas medicinais, a Myracrodruon urundeuva (aroeira) e a Aloe barbadensis (babosa) sobre o desfecho da MO experimental induzida por 5-Fluorouracil (5-FU) em hamsters, atravÃs de escores macro e microscÃpicos e avaliaÃÃo de perda ponderal. Investigar os possÃveis mecanismos envolvidos nesses efeitos, atravÃs de anÃlise da atividade de mieloperoxidase (MPO) e expressÃo tissular de TNF-alfa e iNOS. MATERIAIS E MÃTODOS: Hamsters Goldem siriam receberam injeÃÃes i. p. de 60 e 40 mg/Kg de 5-FU, nos dias 1 e 2, respectivamente. No dia 4 os animais eram anestesiados, tinham suas mucosas jugais submetidas a trauma mecÃnico (TM) com agulha de ponta romba. Em seguida, eram tratadas com gel inerte (controle), gel de aroeira a 5, 10 ou 20% (AR) ou gel de babosa (ALOE) a 25, 50 e 100% . Tais tratamentos eram realizados 2xdia atà o dia 9. Os animais eram pesados diariamente. No dia 10, ocorriam os sacrifÃcios para: 1. AnÃlise macroscÃpica das mucosas; 2. Retiradas de amostras para histopatologia, imunohistoquÃmica para e dosagem de MPO. RESULTADOS: Na anÃlise macroscÃpica, AR determinou inibiÃÃo significativa da MO (AR 5% - Md 2; AR 10% - Md 3; Controle â Md 4), ALOE tambÃm inibiu a MO (ALOE 25% - Md 1; ALOE 50% - Md 1,5; ALOE 100% - Md 1; Controle â Md 4). à histopatologia confirmou-se inibiÃÃo significativa da MO pela AR (p < 0,01) e pela ALOE a 50 e 100% ( p< 0,01). Houve tambÃm inibiÃÃo dos nÃveis de MPO pelos extratos das duas drogas e a expressÃo de TNF-alfa e iNOS tambÃm foi reduzida. Houve uma tendÃncia a uma menor perda ponderal nos grupos experimentais. CONCLUSÃES: Extratos de ALOE e AR foram capazes de inibir a MO experimental induzida por 5-FU atravÃs de aplicaÃÃes tÃpicas e tal efeito pode ser modulado por suas atividades anti-inflamatÃrias sobre a produÃÃo de citocinas envolvidas com o processo e de NO. / INTRODUCTION: Oral mucositis (OM) is a frequent dose-limiting and costly complication of antineoplastic chemotherapy. Itâs caractherized by ulcerative lesions and causes pain, restrict food and fluids oral intake and causes substancial risk for sepsis. In severe cases, hospitalization, parenteral nutrition and opiode analgesics are required. OBJECTIVES: Evaluate the effects of extracts of two herbal medicines, Aloe barbadensis Miller (Ab) and Myracrodruon urundeuva AllemÃo (Mu) on 5-fluorouracil-induced OM in hamsters. To evaluate the possible mechanisms by the extracts act, it was performed analysis of intensity of activity of myeloperoxidase (MPO) and analysis of immunohistochemistry for TNF-alpha and iNOS in mucosa specimens. METHODS: Golden siriam hamsters were submitted to intra-peritoneal 60 and 40 mg/Kg injections of 5-fluorouracil (5-FU) in day 1 and 2, respectively. On day 4, animals were submitted to anaesthesia, followed by mecanic trauma with needle to potenciate the effect of 5-FU. After that, the mucosas were treated with topical gel containing Mu extracts at 5, 10 or 20%, Ab extracts at 25, 50 or 100% (experimental groups) or carbapol gel (control group). The treatments above were mantained twice daily until day 9. On day 10 the animals were sacrified. Diferent parameters were evaluated: macroscopic and microscopic scores of OM, body mass variation and immunohistochemistry for TNF-alpha e iNOS. RESULTS: Mu significantly inhibited macroscopic oral mucositis at 5 and 10% concentrations (5% Mu â Md 2; 10% Mu â Md 3; control â Md 4, p < 0,01). Ab also inhibited OM (25% Ab â Md 1; 50% Ab â Md 1,5; 100% Ab â Md 1; control â Md 4, p < 0,001). These results were confirmed by histological analysis (5% Mu â Md 1,5; 10% Mu â Md 1; 25% Ab â Md 1; 50% Ab â Md 1,5; 100% Ab â Md 1; control â Md 2, p < 0,01). MPO activity was significantly decreased by Mu and Ab compared to control animals. Both Mu and Ab decreased expression of TNF-alpha and iNOS on tissue. It was observed a decrease on ponderal lost in experimental groups. CONCLUSIONS: Myracrodruon urundeuva and Aloe barbadensis cause important inhibitory effects in oral mucositis 5-FU induced probably by their antiinflamatory properties.

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