As distrofias musculares são doenças genéticas causadas por mutações em diferentes genes caracterizadas por degeneração muscular, prejuízos locomotores e, geralmente, morte precoce. Dentre elas, a de Duchenne, causada por mutações no gene que codifica para a proteína distrofina, é a mais comum e grave, tendo os camundongos MDX como modelo experimental mais utilizado. O objetivo do presente estudo foi testar quatro abordagens terapêuticas potencias neste modelo animal, divididas em dois experimentos: 1. treinamento físico voluntário em roda de atividade e/ou drogas agonistas das proteínas AMPK e PPAR em dias alternados (AICAR: 100 mg.Kg-1.dia-1, ip; GW 1516: 5 mg.Kg-1.dia-1, gavagem); 2. células-tronco estromais humanas provenientes de lipoaspiração (um milhão a cada injeção intravenosa; uma injeção a cada 10 dias nos dois primeiros meses de tratamento e injeções mensais nos quatro meses subsequentes) e/ou suplementação com os aminoácidos alanina e glutamina (10 mg.kg-1.dia-1, injeção diária intraperitoneal). Em relação ao primeiro experimento, o principal achado foi que os animais submetidos ao treinamento físico associado às drogas apresentaram índices de função muscular superiores aos outros grupos. Já em relação ao segundo grupo de análises, foi observado que os animais submetidos à terapia celular apresentaram tempo de vida significativamente maior quando comparados aos animais não tratados e aos tratados com ambas as terapias. Tais resultados, nunca demonstrados previamente pela literatura científica, podem contribuir para o entendimento da fisiopatologia das distrofias musculares e para o avanço de potenciais abordagens terapêuticas. / Muscular dystrophies are genetic diseases caused by mutations in different genes. They are characterized by muscle degeneration, motor prejudices and, generally, early death. Among them, Duchenne muscular dystrophy (DMD) is the most common and severe form and it is caused by mutations in the dystrophin gene. The most widely used animal model of DMD is the MDX mouse. The aim of this study was to test four potential therapeutic approaches assigned in two experiments: 1. voluntary exercise training in activity road and/or AMPK and PPAR agonists drugs every other day in MDX mice (AICAR: 100 mg.Kg-1.day-1, IP; GW 1516: 5 mg.Kg-1.day-1, gavage); 2. Intravenous injection of stromal stem cells from human adipose tissue (106 cells every 10 days in the first two months and monthly injections in the following four months) and/or alanine and glutamine amino acids supplementation (10 mg.Kg-1.day-1, daily IP injections). In the first experiment we demonstrated that mdx mice submitted to exercise training associated to drugs presented improved muscle function when compared to the other groups. In the second experiment, on the other hand, it was observed that the animals submitted to cell therapy presented increased survival when compared to non injected animals and animals treated with both approaches. These results, here demonstrated for the first time, can contribute to understand the physiopathology of muscular dystrophies and may give insights for future therapeutic approaches

Made available in DSpace on 2014-10-09T12:28:52Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:06Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP; Faculdade de Odontologia, Universidade de Sao Paulo, Sao Paulo

Made available in DSpace on 2014-10-09T12:33:18Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:16Z (GMT). No. of bitstreams: 0 / Este trabalho tem por objetivo a comparação das propriedades da superfície da poliamida 6.6 tratada por plasma e por radiação ionizante, assim como determinar qual a melhor técnica e condição para ativação da superfície, visando a adesão da mesma e borracha poliacrílica utilizada na fabricação de retentores automotivos. O tratamento da poliamida 6.6 por plasma foi realizado utilizando um equipamento Electronic DIENER Plasma Surface- Technology LFG40, com gás nitrogênio à pressão de 1,40 kg/cm2. As amostras de poliamida 6.6 também foram tratadas por radiação ionizante, à pressão atmosférica e em vácuo, utilizando um acelerador industrial de elétrons, Dynamitron JOB 188, com dose de radiação de 5, 10, 20, 40, 50, 100, 200, 300, 400 e 500kGy com taxa de dose de 11,22 kGy/s para todas as doses e taxa de 11,22 kGy/s e 22,38 kGy/s para a dose de 20kGy. Após os processos de modificação da superfície da poliamida 6.6, parte das amostras não tratadas, tratadas por plasma e por radiação ionizante foram incorporadas à borracha poliacrílica, e outra parte foi destinada a caracterização da superfície utilizando as técnicas de MEV/EDS, FT-IR, PIXE/RBS, AFM e ângulo de contato. As amostras não tratadas e as amostras irradiadas não aderiram à borracha poliacrílica. As amostras tratadas por plasma aderiram à borracha poliacrílica com eficiência e apresentaram diferenças de rugosidade, nas análises de MEV e AFM, e aumento no ângulo de contato quando comparado com as amostras não tratadas. As amostras irradiadas não apresentaram diferenças significativas de propriedades nas análises utilizadas neste trabalho, quando comparadas com as amostras não tratadas. A radiação ionizante não foi eficiente na modificação da superfície da poliamida 6.6 para aderência à borracha poliacrílica. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:26:38Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:27Z (GMT). No. of bitstreams: 1 13948.pdf: 4835457 bytes, checksum: 91031ccf645e496d6c45cf541eb91a26 (MD5) / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP; Faculdade de Odontologia, Universidade de Sao Paulo, Sao Paulo

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This research work studies the influence of zinc on surface treatments such as mechanical polishing, anodic alkaline etching, alkaline etching and electropolishing. Solid-solution binary alloys containing 0.6, 1.0 and 1.9at.%Zn were investigated using scanning and transmission electron microscopies and ion beam analysis. Initially, the near-surface composition of the surface pretreated aluminium alloys were determined using Rutherford backscattering spectroscopy (RBS), medium energy ion scattering (MEIS) and glow discharge optical spectroscopy (GDOES). Subsequently, the surface morphologies of the pretreated specimens were characterized by secondary electron microscopy (SEM) and atomic force microscopy (AFM). Further related work was undertaken on the effect of the employed surface treatments on the anodic behaviour of aluminium-zinc alloys. A final analysis was carried out on the influence of grain orientation on zinc enrichment and surface morphologies of aluminium-zinc alloys developed during alkaline etching.The results reveal that surface pretreatments of aluminium-zinc alloys lead to zinc enrichment at the alloy/film interface. The number of zinc atoms contained in the enriched layer depends upon the employed surface pretreatment and the alloy composition. Surface pretreatments influence the topography of Al-Zn alloys. In particular, for electropolishing, alkaline etching and anodic alkaline etching, the resultant surface morphologies were associated with the oxidation-dissolution-precipitation mechanisms occurring at the alloy/film interface and at the film/solution interface. Anodizing of Al-Zn alloys shows that the anodic films growth on Al-Zn alloys in rolled condition and after surface treatment becomes detached from the substrate independently of the surface treatment employed, although detachment of the anodic film occur earlier on surface pre-treated Al-Zn alloys that developed zinc enrichment. The final studies correlated the mechanisms of oxidation and dissolution with the grain orientation. The result revealed that the (111) grain dissolves faster than other grains, while the higher number of zinc enriched atoms were measured on the (001) grain.

Basal area and dominant height growth and survival models incorporating general response to silvicultural treatments for loblolly pine stands were developed using data from various silvicultural experiments across Southern United States. Growth models for treated stands were developed by multiplying base-line growth models with modifier response functions/multipliers accounting for effects of thinning, fertilization, and control of competing vegetation. Chapman-Richards functions were used to model the base-line growth. Separate response functions to mid-rotation thinning and fertilization effects were developed. The thinning response function was based on duration and rate parameters and is sensitive to stand age at the time of thinning, time since thinning, and intensity of thinning. The fertilization response functions were based on Weibull distribution and the magnitude of responses varies with time since application of fertilizers, type of fertilizer elements applied, and rate of application. Response functions were integrated as a multiplier to base-line models. Response to early control of competing vegetation was incorporated into base-line models through multiplier factors. Multiplier factors were calculated based on growth difference between treated and untreated stands. A difference function, derived from differential equation with age, initial stand density, and site index served as the base-line survival model. The survival model was adjusted for thinning treatment by including an additional independent variable that represents thinning intensity. No adjustment was required for survival model in response to fertilization and competing vegetation control. All growth models were unbiased and had adequate performance in predicting basal area and dominant height following treatments. Models were developed to represent general growth trends in response to treatments. The response functions developed here can be viewed as general response functions. / Ph. D.

Chloroquine was one of the main malarial treatments until the late 1960s when resistance began to emerge. This antimalarial targets haemozoin formation which causes a cytotoxic accumulation of free haem in the malaria parasite leading to parasite death. This is still one of the most promising pathways for treatment of the most prevalent species of malaria parasite, Plasmodium falciparum to date but, owing to growing resistance to chloroquine and other current antimalarial drugs, there is a dire need for new drugs. One strategy is to investigate non-chloroquine haemozoin inhibitors. High-throughput screening (HTS) was previously used to investigate novel β-haematin (synthetic haemozoin) inhibitors with promising P. falciparum growth inhibition activities. Of the 144 330 compounds screened, two hit compounds were selected for investigation in this project with two different scaffolds, namely benzimidazole and carbazole indole. In order to preselect benzimidazole derivatives for synthesis, Discovery Studio and Pipeline Pilot where used in tandem to enumerate 325 728 in silico compounds. These were filtered according to predicted β-haematin inhibition activities, followed by predicted malaria parasite growth activities using previously developed models based on Bayesian statistics. The predicted active compounds were further subjected to an in silico aqueous solubility model and separated according to predicted solubility values however, only 68 out of the 35 124 active compounds showed moderate solubility whilst the rest were poorly soluble. From this data, eighteen compounds were chosen for synthesis with varying functional groups. Using the same Bayesian models, biological activities for seven fragment compounds derived from the benzimidazole hit compound were predicted. Six out of seven were predicted to be β-haematin inhibitors while five out of seven were predicted active against the malaria parasite growth inhibition model. Similar Bayesian predictions were carried out on the seven proposed carbazole indole compounds with three compounds predicted to be β-haematin inhibitors while six compounds were predicted to be active against the malaria parasite growth inhibition model. The eighteen benzimidazole compounds were synthesized using a two-step synthesis, via a condensation reaction using polyphosphoric acid (PPA), 4-aminobenzoic acid and o-phenylenediamine to form the primary amine benzimidazole intermediate after which ani acylation reaction with the appropriate acid chloride furnished the desired compounds. β-haematin inhibition analysis revealed a 78% hit rate compared to the Bayesian predictions which resulted in a 24-fold enrichment compared to random screening. SAR analysis revealed an activity trend related to the position of substituents on the ring system as follows: para < ortho < meta. The type of ring system was also investigated, with a trend of phenyl < furan < pyrrole < thiophene < pyridyl found. The fragment compounds were either purchased or synthesized via standard acylation conditions using acid chlorides or acetic anhydride with primary amines as before. β-haematin inhibition analysis showed all these compounds to be inactive at the 100 µM cut-off but these compounds were still carried through to the next stage of testing in spite of these results. Molecular docking was carried out on all eighteen benzimidazole compounds in Materials Studio using the (001) and (011) β-haematin crystal faces for adsorption, together with a modified CVFF force-field. This showed a correlation between adsorption energies of the (011) β-haematin crystal face with the experimental β-haematin inhibition values. This indicated that the (011) β-haematin crystal face was the most important for β-haematin inhibition. Analysis of the benzimidazole compounds and their π-π and hydrogen bonding interactions was performed. The number of π-π interactions were found to be important for β-haematin inhibition activity. Both sets of benzimidazole compounds were tested against the NF54 chloroquine sensitive malaria parasite using growth inhibition assays with a 50% hit rate shown for the benzimidazole compounds and a 71% hit rate for the fragment study leading to a 26-fold and 36-fold enrichments compared to random screening. SAR analysis of the benzimidazole compounds revealed a trend for activity in relation to substituent position of para ≈ ortho < meta and a ring system trend of phenyl < pyridyl < thiophene < furan < pyrrole. The benzimidazole compounds were further tested against the chloroquine resistant Dd2 P. falciparum strain which showed that disubstituted compounds were more active against this strain. Cellular haem fractionation studies revealed an increase in free haem and decrease in haemozoin confirming that haemozoin inhibition is the mode of action for the benzimidazole compounds. QSAR analysis of these compounds revealed a correlation between the -Log(P. falciparum IC50) which is also known as pLog(P. falciparum IC50) and 1/βhaematin IC50, number of hydrogen bond donors and molecular depth with 1/β-haematin IC50 the most dominant term. iv The first four carbazole indole compounds were synthesized using a two-step synthesis via deprotonation of carbazole and reaction with epichlorohydrin or 1,3-dibromopropane to furnish the epoxide or alkylbromine intermediates. These intermediates underwent a further SN2 reaction using deprotonated indole to furnish four final compounds. Synthesis of another three derivatives required benzyl protection of 7-hydroxyindole alcohol first, followed by reaction with the epoxide intermediates via an SN2 mechanism to furnish the final three compounds. Analysis using the turbidimetric solubility assay revealed the best aqueous solubility range of this series of compounds to be 10-20 µM (moderately soluble). β-haematin inhibition studies were carried out on this series of compounds with a 100% hit rate found when compared to the Bayesian model data which lead to 30-fold enrichment when compared to random screening. SAR analysis showed an increase in the number of hydroxyl groups led to an increase in β-haematin inhibition activity. Docking studies were performed on these seven compounds and showed that hydrogen bonding played a role in anchoring the molecules in the binding pocket on the crystal surface with increased adsorption energies seen with an increase in the number of hydroxyl groups. Malaria parasite growth inhibition studies showed no compounds to be active against the NF54 and Dd2 strains at the 2 µM cut-off. Cellular haem fractionation studies on the carbazole indole compounds showed that this series of compounds acts via a mechanism that results in inhibition of haemoglobin uptake into the food vacuole and not via haemozoin inhibition.

Thesis (M.S.)--Boston University / This study was designed to determine whether education, marital status, sex, age and religion are factors influencing the time lapse between onset of symptoms and the seeking of medical attention with cancer of the colon.

Artemisinin is produced in the leaves of Artemisia annua and is currently one of the most valuable antimalarial treatments. A. annua is of Asian origin but many other family members have been identified worldwide. A. annua however, is the only one that produces artemisinin. Synthetic production of artemisinin is not yet feasible, not to mention very expensive and the product yields are relatively low. The aims of this study were threefold: 1) To regenerate callus, cell cultures and plants from genetically modified root cultures of A. afra into which an artemisinin biosynthetic gene was inserted from A. annua 2) To investigate the probability that fungal endophytes are responsible for the production of artemisinin and 3) To establish two fields of high yielding varieties of A. annua plants and evaluate whether artemisinin production of these two locations will remain high. Callus and cell cultures of the genetically modified A. afra root cultures were established, but no shoots have been produced as of yet and this is an on-going investigation. Fungal endophytes were sampled and none of the endophytes produced artemisinin. Five different lines of A. annua were cultivated, successfully grown and harvested. Measurements were taken at different stages of processing, these were compared and analysed using various methods such as height and mass comparisons. Comparisons revealed that the production of artemisinin is correlated to local sets of conditions rather than the variety of individual lines. The genetic potential to produce high quantities of artemisinin appears to have been lost, instead of being maintained. We confirmed that secondary compound production and specifically, artemisinin, is enhanced by certain stress factors on the plants. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Plant Science / unrestricted