Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The essential oils obtained from plants used as condiments are an important source of compounds with pharmacologic activity. In the present study, the antiviral activity of the essential oil of Ocimum basilicum L. (basil) and from the monoterpens camphor, 1,8-cineol and timol was tested against the bovine viral diarrhea virus (BVDV), while the essential oil of Rosmarinus officinalis L. (rosemary), Lippia graveolens HBK. (mexican oregano) and Thymus vulgaris L. (thyme) were tested against the feline calicivirus (FCV). The colorimetric test MTT ([3- (4.5-dimetilazol-2-il)-2.5-brometo of difeniltetrazolium]) was applied for the measurement of cytotoxicity, and the antiviral tests were performed by the plaque reduction assay. Three different protocols were applied: a) the virus was incubated with the essential oils or compounds before the inoculation into cells (virucidal assay); b) the cells were treated with the essential oils or compounds prior to virus inoculation; or, c) essential oils and compounds were added to the cells after virus inoculation and maintained for 72 hours. The results were expressed as CC50 (cytotoxic concentration to 50% of the cell culture), IC50 (inhibitory concentration to 50%) and SI (selectivity index = CC50/IC50). The best results were evidenced for the monoterpens camphor (SI=13.88) and the 1,8-cineol (IS=9.05) against BVDV. These results were obtained from the virucidal protocol and these compounds showed also the lower toxicicity towards the bovine kidney cells culture (Madin-Darby bovine kidney cells = MDBK) (CC50 = 4420.12 μg/mL and 2996.10 μg/mL, respectively). Regarding to the tests with FCV, the thyme essential oil showed the best results with SI=8.57 for c treatment. The basil essential oil had a moderate action in the a protocol (SI=6.54) and also for the c protocol (SI=6.86). In addition, the basil essential oil exhibited low levels of cytotoxicity towards the Crandel-Reese feline kidney cells (CRFK), with CC50 of 1300.21 μg/mL. In conclusion, the essential oils and monoterpens examined showed different levels of inhibitory activity on diverse moments of the viral infection. The antiviral activity demonstrated by the essential oils and compounds on BVDV and FCV may suggest a possible action on the hepatitis C virus (HCV) and norovirus (NoVs), respectively; since BVDV ande FCV shows several structural and replicative similarities to HCV and NoVs. / Óleos essenciais obtidos de plantas utilizadas como condimentos constituem uma fonte de compostos com promissoras atividades farmacológicas. No presente estudo, a atividade antiviral do óleo essencial de Ocimum basilicum L. (manjericão) e dos monoterpenos cânfora, 1,8-cineol e timol foi testada frente ao vírus da diarréia viral bovina (BVDV), enquanto que os óleos essenciais de Rosmarinus officinalis L. (alecrim), Lippia graveolens HBK. (orégano mexicano) e Thymus vulgaris L. (tomilho) foram testados frente ao calicivírus felino (FCV). O teste colorimétrico com MTT ([3- (4,5-dimetilazol-2-il)-2,5-brometo de difeniltetrazolium]) foi aplicado para a detecção de citotoxicidade, já os testes de atividade antiviral foram realizados através da metodologia de ensaio de redução de placas. Para este, três diferentes protocolos foram aplicados: o vírus foi incubado com os óleos essenciais ou compostos antes da infecção viral (ensaio virucida); as células foram pré tratadas com os óleos essenciais ou compostos antes da inoculação do vírus; ou as células infectadas foram incubadas com esses após as 2 horas de adsorção viral. Os resultados foram expressos como CC50 (concentração citotóxica para 50% do cultivo celular), CI50 (concentração inibitória para 50%) e IS (índice de seletividade = CC50/CI50). Os resultados de atividade frente ao BVDV evidenciaram, no geral, uma boa ação antiviral exercida pelos monoterpenos, sendo que a cânfora (IS=13,88) seguida do 1,8-cineol (IS=9,05) foram os compostos que apresentaram os mais elevados índices de seletividade obtidos no ensaio virucida, bem como a menor toxicidade frente às células de linhagem de rim bovino (Madin-Darby bovine kidney cells = MDBK) (CC50 = 4420,12 μg/ml e 2996,10 μg/ml, respectivamente). Em relação aos testes com FCV, o óleo essencial de tomilho mostrou os melhores resultados, com índice de 8,57 para o tratamento no qual os óleos essenciais foram adicionados às células antes da inoculação viral. Já o óleo essencial de alecrim, além de apresentar uma moderada ação nos ensaios virucida (IS=6,54) e de pós-tratamento (IS=6,86), exibiu baixos níveis de toxicidade em relação às células de linhagem de rim felino (Crandell-Reese feline kidney = CRFK), com CC50 de 1300,21 μg/ml. Dessa forma, conclui-se que os óleos essenciais e monoterpenos em estudo apresentaram algum nível de atividade inibitória em diferentes momentos da infecção viral.

Made available in DSpace on 2014-07-29T15:16:30Z (GMT). No. of bitstreams: 1 pre textuais aline franca.pdf: 261338 bytes, checksum: 26489ba3dd2eb948a58b73b531aee0b2 (MD5) Previous issue date: 2010-10-05 / The evaluation of the reproductive capacity of stallions and semen cooled and / or frozen is of fundamental importance in practical breeding of horses. Whereas predicting the fertility of a stallion is still a subjective decision, the present study was conducted to evaluate different staining techniques, as well as tests that assess the viability of semen in horses, studying the effects of the addition of cysteine and glutathione in plasma membrane integrity of sperm DNA, and to evaluate the effects of the addition of these antioxidants in preserving the viability of sperm undergoing incubation and refrigerated for short periods. We used semen from six stallions, wich were split into seven samples, one kept as control (Control Group) and other antioxidants cysteine was added at a ratio of 1.0 mM (Group C1, 0), 1.5 mM (Group C1, 5), 2.5 mM (Group C 2.5) and glutathione also at 1.0 mM (Group G1, 0), 1.5 mM (Group G1, 5) and 2.5 mM (Group G 2.5 ). All tests were performed every six hours. The three treatments were: Treatment I cooled to 12 &#8304;C for 12 hours (zero hour; 6h resf.; 12h resf.) Chilled in boxes; Treatment II incubated in a water bath at 37 &#8304;C for 12 hours (6h 37 ° C, 12h 37 ° C) and Treatment III - cooled and subsequently incubated, according to the treatments I and II. The evaluation of plasma membrane integrity was performed by staining eosine-nigrosin; acrosomal membrane by FITC-PSA and DNA by acridine orange. For each analysis were numbered 200 to 500 cells. The evaluation of the viability of sperm was performed by MTT assay according to Mosmann (1983). The results showed that antioxidants were effective (p <0.05) in keeping the DNA intact chromatin, especially glutathione. In the acrosome of antioxidants were protective, at times 18 and 24 hours, and in other treatments, no significant difference (p> 0.05) between control and treated groups. The MTT test showed that groups treated with antioxidants had absorbance values similar to those of control, showing positive effect (p <0.05) only when cooled by six o'clock in the cysteine group 2.5. In relation to the plasma membrane of spermatozoa stained with eosin-nigrosin, no protective effect of antioxidants in the samples. The values of their averages were close to the control group (p> 0.05). One factor was estimated that cooling per se, independent of the addition of antioxidants used, has been effective in protecting the sperm. And the incubation at 37 &#8304; C causes these cells, and the addition of cysteine and glutathione were efficient, if not protect, but to maintain the integrity of the factors evaluated, not causing more damage to sperm. / A avaliação da eficácia reprodutiva do garanhão e do sêmen resfriado e&#8260;ou congelado é de fundamental importância na prática reprodutiva dos eqüinos. Predizer a fertilidade de um garanhão constitui uma decisão subjetiva. O presente estudo foi realizado com o objetivo de testar diferentes técnicas de coloração, assim como testes que avaliem a viabilidade do sêmen de eqüinos, estudando os efeitos da adição de cisteína e glutationa na integridade da membrana plasmática, do DNA espermático, além de avaliar os efeitos da adição desses antioxidantes na preservação da viabilidade dos espermatozóides submetidos à incubação e refrigeração por curtos períodos. Foi utilizado sêmen de seis garanhões, que foram fracionados em sete amostras, sendo uma mantida como controle (Grupo Controle) e às outras foi adicionado os antioxidantes cisteína, na proporção de 1,0mM (Grupo C1,0); 1,5mM (Grupo C1,5); 2,5mM (Grupo C 2,5) e glutationa também na proporção de 1,0mM (Grupo G1,0); 1,5mM (Grupo G1,5) e 2,5mM (Grupo G 2,5). Todas as análises foram realizadas a cada seis horas. Os três tratamentos foram: Tratamento I resfriado a 12 °C, por 12 horas (zero hora; 6h resf.; 12h resf.), em caixas refrigeradas; Tratamento II incubado em banho-maria a 37 °C, por 12 horas (6h 37° C; 12h 37° C) e Tratamento III resfriado e posteriormente incubado, conforme os Tratamentos I e II. A avaliação da integridade da membrana plasmática foi feita pela coloração eosina-nigrosina; da membrana acrossomal pelo FITC-PSA e do DNA pela laranja de acridina. A avaliação da viabilidade do sêmen foi realizada pelo ensaio do MTT, de acordo com Mosmann(1983). Os resultados obtidos mostraram que os antioxidantes foram eficientes (p<0,05) em manter a cromatina do DNA intacta, especialmente a glutationa. Na membrana acrossomal houve proteção dos antioxidantes, nos momentos 18 e 24 horas, sendo que nos demais tratamentos, não houve diferença significativa (p>0,05) entre os grupos tratados e o grupo controle. O teste do MTT mostrou que os grupos tratados com antioxidantes tiveram valores de absorbância próximos aos do controle, mostrando efeito positivo (p<0,05) apenas quando resfriados por seis horas, no grupo cisteína 2,5. Em relação à membrana plasmática dos espermatozóides, corados por eosina-nigrosina, não houve efeito protetor dos antioxidantes nas amostras avaliadas. Um fator avaliado foi que o resfriamento, por si só, independente da adição dos antioxidantes utilizados, já foi eficaz em proteger os espermatozóides. E a incubação a 37&#8304; C causa danos a essas células, e a adição de cisteína e glutationa foi eficiente em, senão proteger, mas manter a integridade dos fatores avaliados, não causando mais danos aos espermatozóides.

Water is considered the most vital resource on earth and its quality is deteriorating. Not all residents living in South Africa‘s rural areas have access to treated drinking water, and use water from rivers, dams, and wells. The quality of these resources is unknown, as well as the effects of the bacteria in the water on human health. The heterotrophic plate count (HPC) method is a globally used test to evaluate microbial water quality. According to South African water quality guidelines, water of good quality may not contain more than a 1 000 coliforming units (CFU)/mℓ. There is mounting evidence that HPC bacteria may be hazardous to humans with compromised, underdeveloped, and weakened immune systems. In this study the pathogenic potential of HPC bacteria was investigated. Samples were collected from boreholes in the North West Province and HPCs were enumerated with a culture-based method. Standard physico-chemical parameters were measured for the water. Different HPC bacteria were isolated and purified and tested for α- or β-haemolysis, as well as the production of extracellular enzymes such as DNase, proteinase, lecithinase, chondroitinase, hyaluronidase and lipase, as these are pathogenic characteristics. The isolates were identified with 16S rRNA gene sequencing. The model for the human intestine, Hutu-80 cells, were exposed to the potentially pathogenic HPC isolates to determine their effects on the viability of the human cells. The isolates were also exposed to different dilutions of simulated gastric fluid (SGF) to evaluate its effect on the viability of bacteria. Antibiotic resistant potential of each isolate was determined by the Kirby-Bauer disk diffusion method. Three borehole samples did not comply with the physico-chemical guidelines. Half of the samples exceeded the microbial water quality guideline and the greatest CFU was 292 350 CFU/mℓ. 27% of the isolate HPC bacteria were α- or β- haemolytic. Subsequent analysis revealed the production of: DNase in 72%, proteinase in 40%, lipase and lecithinase in 29%, hyaluronidase in 25% and least produced was chondroitinase in 25%. The HPC isolates identified included: Alcaligenes faecalis, Aeromonas hydrophila and A. taiwanesis, Bacillus sp., Bacillus thuringiensis, Bacillus subtilis, Bacillus pumilus, Brevibacillus sp., Bacillus cereus and Pseudomonas sp. All the isolates, except Alcaligenes faecalis, were toxic to the human intestinal cells to varying degrees. Seven isolates survived exposure to the most diluted SGF and of these, four isolates also survived the intermediate dilution but, only one survived the highest SGF concentration. Some isolates were resistant to selected antibiotics, but none to neomycin and vancomycin. Amoxillin and oxytetracycline were the least effective of the antibiotics tested. A pathogen score was calculated for each isolate based on the results of this study. Bacillus cereus had the highest pathogen index with declining pathogenicity as follows: Alcaligenes faecalis > B. thuringiensis > Bacillus pumilus > Pseudomonas sp. > Brevibacillus > Aeromonas taiwanesis > Aeromonas hydrophila > Bacillus subtilis > Bacillus sp. The results of this study prove that standard water quality tests such as the physico-chemical and the HPC methods are insufficient to provide protection against the effects of certain pathogenic HPC bacteria. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014

Water is considered the most vital resource on earth and its quality is deteriorating. Not all residents living in South Africa‘s rural areas have access to treated drinking water, and use water from rivers, dams, and wells. The quality of these resources is unknown, as well as the effects of the bacteria in the water on human health. The heterotrophic plate count (HPC) method is a globally used test to evaluate microbial water quality. According to South African water quality guidelines, water of good quality may not contain more than a 1 000 coliforming units (CFU)/mℓ. There is mounting evidence that HPC bacteria may be hazardous to humans with compromised, underdeveloped, and weakened immune systems. In this study the pathogenic potential of HPC bacteria was investigated. Samples were collected from boreholes in the North West Province and HPCs were enumerated with a culture-based method. Standard physico-chemical parameters were measured for the water. Different HPC bacteria were isolated and purified and tested for α- or β-haemolysis, as well as the production of extracellular enzymes such as DNase, proteinase, lecithinase, chondroitinase, hyaluronidase and lipase, as these are pathogenic characteristics. The isolates were identified with 16S rRNA gene sequencing. The model for the human intestine, Hutu-80 cells, were exposed to the potentially pathogenic HPC isolates to determine their effects on the viability of the human cells. The isolates were also exposed to different dilutions of simulated gastric fluid (SGF) to evaluate its effect on the viability of bacteria. Antibiotic resistant potential of each isolate was determined by the Kirby-Bauer disk diffusion method. Three borehole samples did not comply with the physico-chemical guidelines. Half of the samples exceeded the microbial water quality guideline and the greatest CFU was 292 350 CFU/mℓ. 27% of the isolate HPC bacteria were α- or β- haemolytic. Subsequent analysis revealed the production of: DNase in 72%, proteinase in 40%, lipase and lecithinase in 29%, hyaluronidase in 25% and least produced was chondroitinase in 25%. The HPC isolates identified included: Alcaligenes faecalis, Aeromonas hydrophila and A. taiwanesis, Bacillus sp., Bacillus thuringiensis, Bacillus subtilis, Bacillus pumilus, Brevibacillus sp., Bacillus cereus and Pseudomonas sp. All the isolates, except Alcaligenes faecalis, were toxic to the human intestinal cells to varying degrees. Seven isolates survived exposure to the most diluted SGF and of these, four isolates also survived the intermediate dilution but, only one survived the highest SGF concentration. Some isolates were resistant to selected antibiotics, but none to neomycin and vancomycin. Amoxillin and oxytetracycline were the least effective of the antibiotics tested. A pathogen score was calculated for each isolate based on the results of this study. Bacillus cereus had the highest pathogen index with declining pathogenicity as follows: Alcaligenes faecalis > B. thuringiensis > Bacillus pumilus > Pseudomonas sp. > Brevibacillus > Aeromonas taiwanesis > Aeromonas hydrophila > Bacillus subtilis > Bacillus sp. The results of this study prove that standard water quality tests such as the physico-chemical and the HPC methods are insufficient to provide protection against the effects of certain pathogenic HPC bacteria. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014

HIV/AIDS is the most threatening and challenging infectious diseases of our time, with the highest increase of newly infected cases reported. This infectious disease was discovered in the early eighties under homosexual men and was later to be discovered in heterosexuals. HIV is a systemic immunosuppressive disorder which causes a depletion of CD4+ T cells and develops into the acquired immunodeficiency syndrome - AIDS. Africa is the continent most affected by HIV/AIDS with the southern parts of Africa having the highest prevalence rates compared to the rest of Africa. Statistics indicate that AIDS is responsible for 3% of deaths in children worldwide - one in seven people dying of an HIV-related illness is a child under the age of 15 years. It was stated by the WHO that countries should develop improved antiretrovirals regimes for the prevention of mother-to-child transmission. Difficulties in administering antiretrovirals (ARVs) to patients (especially children) are the strict dosage regimes and the severe adverse reactions. These factors complicate patient adherence. The list of problems in treating patients is endless and includes the distribution, stability as well as the low efficacy of these drugs. Most of the above mentioned problems and obstacles related to ARVs and ARV treatment could be minimized or eliminated by the use of a stable and effective drug delivery system. Enhancing ARV treatment may be accomplished by the use of the Pheroid™ drug delivery system. Pheroids™ consists mainly of fatty acids and sterile nitrous oxide gassed water. Pharmacological active substances are entrapped into submicron and micron sized structures called Pheroids™. Research showed promising results and advantages in delivering drugs through oral and transdermal routes using Pheroid™ technology. The focus of this study was to test the possible enhancement of the efficacy of antiretrovirals using Pheroid™ technology. The assays used to study this possible enhancement were a modified neutral red and a modified 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay. These assays confirmed and illustrated the toxic and protective properties of the tested ARVs (stavudine, lamivudine and nevirapine). An MT-2 cell line was used and infected with an HIV-1 strain, SW7-TCL. Applying Pheroid™ technology in these assays resulted in massive cell death, due to increased ARV toxic levels within the cells. Viability tests proved that Pheroids™ had no effect on the viability of cells at the concentration typically used. This confirmed the enhancing properties of Pheroids™ in the delivery of drugs into the cells. The MTT assay was further adapted from a seven day incubation period to a three day incubation period. By using a low concentration series and a three day incubation period the loss of cells through toxicity was partially overcome. One of the problems that arose form this study was the non-reproducibility of the results. Absorbance levels fluctuated at specific concentrations of the same ARV, which cause difficulties in comparing results. This result was repeatedly confirmed in this syncytium forming infection model. In conclusion, Pheroid™ technology enhanced the delivery of ARVs into the cells although it resulted in cell death. Both the neutral red and MTT assays were found to be inaccurate but further development, research and assay optimization could result in improved in vitro studies. The article format was used for this thesis, as described in the general academic rules in section A.13.7.3 of the North West University. Chapter 1 deals with HIV/AIDS related problems, statistics and treatment obstacles. Chapter 2 is a summary of the cell viability assays used in this study. Pheroid™ technology and its application to ARV treatment are dealt with in chapter 3. The proposed article for submission in the journal Cell Death and Differentiation has been included in chapter 4. Some of the results from the study are reported in the article and annexures, whilst other results are shown and discussed in Chapter 5. Chapter 6 gives a conclusion and final summary of this study. All other experimental methods and results are enclosed in the annexures, as is the "Guide for authors" for the article. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2008.

β-sitosterol/poly(ethylene glycol)-block-poly(lactic acid) (PLA-b-PEG) complexes were prepared by solution blending in purified water and ethanol. The mixture of water and ethanol is a suitable solvent system for the two components. The complex was studied by using Nuclear Magnetic Resonance (NMR) spectroscopy and Differential Scanning Calorimetry (DSC). β-sitosterol is a drug that may reduce the swelling of benign prostatic hyperplasia (BPH) and diminishing inflammation. However, it is hydrophobic and difficult to deliver in aqueous solution. Since PLA-b-PEG has amphiphilic properties, the complex described here may enhance delivery of this drug for treatment of BPH. Proton NMR (1HNMR) of the complexes shows that the methylene (CH2) protons of the PEG, the (-O-CH-) of PLA, and (CH3) of PLA are slightly shifted because of its non-covalent interaction with β-sitosterol. The complex formation was supported by 2-D NMR (NOESY) spectroscopy. NOESY spectra show cross peaks, indicating the interaction between the two components. DSC of the complexes shows thermal characteristics that are different from the individual components. In particular, the PEG in the complex shows a lower melting point and decreased crystallinity compared to the pure PEG. The melting point is lowered from 57°C to 55.3 °C for the PEG-b-PLA/β-sitosterol (5%) complex. Under the same condition, the melting point of PLA dropped from 170 °C to 130 °C. Atomic force microscopy shows changes in the surface morphology of the copolymer from crystalline to amorphous when incorporated with the drug. NMR, DSC, AFM, and MTT assay studies suggest the formation of a relatively stable β-sitosterol/poly(lactic acid)-block-poly(ethylene glycol) complex. The cell proliferation assay (MTT assay) suggests significant inhibition of the stimulation of growth of prostate cancer cells upon addition the complex.

Submitted by Ana Rosa Silva (arosa@ufpa.br) on 2012-07-24T16:07:36Z No. of bitstreams: 1 Dissertacao_AvaliacaoInvitroEfeitos.pdf: 1085178 bytes, checksum: 83f435e455b064d961678f20dda86aa1 (MD5) / Approved for entry into archive by Ana Rosa Silva(arosa@ufpa.br) on 2012-07-24T16:23:51Z (GMT) No. of bitstreams: 1 Dissertacao_AvaliacaoInvitroEfeitos.pdf: 1085178 bytes, checksum: 83f435e455b064d961678f20dda86aa1 (MD5) / Made available in DSpace on 2012-07-24T16:23:51Z (GMT). No. of bitstreams: 1 Dissertacao_AvaliacaoInvitroEfeitos.pdf: 1085178 bytes, checksum: 83f435e455b064d961678f20dda86aa1 (MD5) Previous issue date: 2011 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A leishmaniose é considerada um problema de saúde pública, principalmente devido à presença de diferentes espécies enzoóticas de Leishmania, envolvendo muitos hospedeiros e diferentes insetos vetores. Os antimoniais pentavalentes permanecem como as drogas de primeira escolha para o tratamento das leishmanioses há mais de 50 anos, no entanto, sua utilização vem sendo comprometida devido, principalmente, a resistência desenvolvida pelo parasita ao medicamento. Assim, a escolha de drogas derivadas de plantas baseada no estudo e utilização de práticas da medicina tradicional devem aparecer como nova estratégia para o controle da leishmaniose. No entanto, é importante verificar que algumas destas drogas podem ser tóxicas ao organismo, podendo inclusive apresentar propriedades genotóxicas, causando alterações no DNA com conseqüente aumento no risco de carcinogênese. A Julocrotina (2-[N-(2-methylbutanolyl)]- N-phenylethylglutarimide) é um alcalóide glutarimida isolado da espécie Croton pullei var. glabrior Lanj. Euphorbiaceae), encontrada amplamente na Floresta Amazônica e conhecido por possuir potente efeito leishmanicida. Desta forma, no presente estudo avaliamos o efeito citotóxico e genotóxico da Julocrotinaa partir do Ensaio do MTT e Ensaio do Cometa (versão alcalina) em cultura de linfócitos humanos. Como resultado, o alcalóide não demonstrou citotoxicidade em linfócitos humanos nas concentrações testadas. No entanto, a julocrotina mostrou-se genotóxica para linfócitos humanos tratados com a maior concentração (632μM) da substância. Apesar dos resultados de citotoxicidade parecem promissores no que diz respeito ao uso da julocrotina no tratamento da leishmaniose, o efeito genotóxico observado reforça a necessidade de se obter as devidas precauções quanto ao seu uso como fitoterápico leishmanicida. / Leishmaniasis is considered a public health problem, mainly due to the presence of different species of enzootic Leishmania, involving many different hosts and insect vectors. The pentavalent antimony remain the first choice drugs for the treatment of leishmaniasis for more than 50 years, however, its use has been compromised due mainly to the parasite developed resistance to the drug. Thus, the choice of drugs derived from plants based on the study and use of traditional medicine practices should appear as a new strategy for the control of leishmaniasis. However, it is important to note that some of these drugs can be toxic to the body and may even have genotoxic properties, causing changes in DNA with consequent increased risk of carcinogenesis. Julocrotine (2 -[N-(2-methylbutanolyl)]-N-phenylethylglutarimide) is an alkaloid isolated from the species Croton pullei var. glabrior Lanj. (Euphorbiaceae), widely found in the Amazon jungle and known to possess potent leishmanicidal effect. Thus, the present study evaluated the cytotoxic and genotoxic effects of julocrotina using the MTT and the Comet Assays in cultured human lymphocytes. Our results showed that the alkaloid did not show cytotoxicity in human lymphocytes at the concentrations tested. However, julocrotine showed to be genotoxic to human lymphocytes treated with the highest concentration (632μM) of the substance. Although the cytotoxicity results seem promising with respect to the use of julocrotina in the treatment of leishmaniasis, the genotoxic effect observed reinforces the need to obtain the necessary cautions for its use as an herbal leishmanicidal.

Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2018-03-26T15:15:34Z No. of bitstreams: 2 Dissertação - Jéssica Fernanda Bertolino - 2018.pdf: 1738703 bytes, checksum: 494fae0cabd867aa9612c7de9a5f3a96 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-27T12:09:19Z (GMT) No. of bitstreams: 2 Dissertação - Jéssica Fernanda Bertolino - 2018.pdf: 1738703 bytes, checksum: 494fae0cabd867aa9612c7de9a5f3a96 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-03-27T12:09:20Z (GMT). No. of bitstreams: 2 Dissertação - Jéssica Fernanda Bertolino - 2018.pdf: 1738703 bytes, checksum: 494fae0cabd867aa9612c7de9a5f3a96 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-01 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Recent researches in bioscience have been focusing in the development of biocompatible materials to replace parts or function of living organisms. Moreover, versatility, low cost and minimally tissue recctiveness are some of the major interest in biomaterial research. Several synthetic and natural resources have been developed. Biometareial components’ features and particularities must be thoroughly assessed to assure standardization and quality of the final product. The purpose of this research was to develop and assess physicochemical and biological features of a chitosan, pequi oil and gelatine based membrane for use in tissue regeneration. Components were mixed in a proportion that kept homogeneity and integrity of the membrane. Membrane’s thermal analysis, scanning electron microscopy, cytotoxicity and bactericidal/bacteriostatic and fungicidal/fungi- static features were evaluated. It was observed that the membrane presented compatible characteristics to be used in soft tissues and that there was no interaction between the components. The presence of pequi oil did not interfere in the biomaterial cytotoxicity. Tests with microorganisms revealed that there was no death or reduction of microorganism proliferation. It was concluded that the mixture of the components allows to obtain a material in the membrane format, however, new investigations are necessary to understand the mechanisms involved in the presented cytotoxicity, as well as the behavior towards the microorganisms in the presence of enzymes that degrade the material, simulating conditions of the animal organic fluid. / Nas últimas décadas houve aumento nas pesquisas para criação de materiais biocompatíveis que possam substituir parte ou função de organismos vivos, de maneira prática e de baixo custo, sem causar injúrias teciduais. O objetivo desse estudo foi o desenvolvimento, caracterização físico-química e biológica de membrana constituida por quitosana, óleo de pequi e gelatina, visando a possível utilização para auxiliar na regeneração tecidual. Para isto, foram obtidas misturas dos componentes em proporções que mantivessem o material homogêneo e não fragmentado. Para a caracterização, utilizou-se análise térmica, microscopia eletrônica de varredura, testes de citotoxicidade e atividade bactericida/bacteriostática e fungicida/fungiostática das membranas. Observou-se que a membrana apresentou características compatíveis para emprego em tecidos moles e que não houve interação química entres os componentes. A presença do óleo de pequi não interferiu na citotoxicidade do biomaterial. Os testes com microrganismos revelaram que não houve morte e nem redução da proliferação de micro-organismos. Concluiu-se que a mistura dos componentes permite a obtenção de um material no formato de membrana, no entanto são necessárias novas investigações para compreender os mecanismos envolvidos na citotoxicidade apresentada, bem como o comportamento frente aos micro-organismos na presença de enzimas que degradem o material, simulando condições do fluido orgânico animal.

This research focused on the cytotoxic properties of RRR-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) in transformed and cancerous cell lines. We used RAW264.7 macrophage and prostate cancer (LNCaP) cell lines in this study. TPGS caused cell death and decreased cell viability in a dose and time dependent manner. Cell death was evaluated fluorimetrically by employing the nucleic acid-binding fluorophore; propidium iodide. A colorimetric 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay was used to evaluate cell viability. Cell death can occur through necrosis or apoptosis. Our results suggested that TPGS triggered apoptotic cell death. Induction of apoptosis, as measured by caspase 3 enzymatic activity, was dependent upon the TPGS dose and incubation time. Caspase 8 was activated before caspase 9, suggesting the importance of the death receptor pathway in apoptosis. Our results indicated that TPGS cytotoxicity could also be due to one of its products of hydrolysis, alpha-tocopheryl succinate.

Due to the rapid development of telecommunication devices, operating speeds are getting faster and more power is being consumed by those devices. Therefore, there is a big concern on how to prolong the battery life in order to fit consumers’ needs. Power amplifiers (PA) at the front end of wireless equipment have drawn a big concern from engineers because of their large power consumption in the system. There is a lot research conducted on PA solutions for improving power-added efficiency (PAE) of amplifiers. PAE is a figure of merit representing how efficient the PA converts DC power to RF power. With PAE increased, the device is able to output the same amount of power with less DC power consumed. Non-linear Class-F and Class-F-1 PAs have drawn the most attention among all different classes of PAs from engineers because of their capability of outputting high power and providing good PAE. Class-F boosts up PAE by controlling the harmonic content at the output. Advanced Design System (ADS) from Agilent is used for design and simulation based on the ADS model of Cree’s CGH40010 high electron mobility transistor (HEMT). A high efficiency power amplifier is fabricated on RT/duroid 5870 high frequency laminate board. In this design, the harmonics at the input are controlled as well as the harmonics at the output. An input wave-shaping network is designed to shape the waveforms at the gate. In this case, the PAE is boosted 30% higher than the PA with only the output wave-shaping network. By terminating harmonics with proper impedances at the output, a square voltage waveform and a half-sine current waveform are obtained at the transistor drain terminal. The overlapping area between the voltage and current waveforms can be reduced as well as the active device power consumption. The final design operating at 1GHz produced a PAE of 89% with 38.35dBm output power in simulation and PAE of 78% with 38.7dBm output power as the result of the IEEE PA design contest. The thesis has shown the effectiveness of the Class-F PA to boost up PAE by preventing the 2nd and 3rd harmonic power from delivering to the load and shaping the waveforms at the transistor terminals. It also shows the benefit of using radial stubs in wave-shaping networks over open-circuit stubs.