Over 200,000 cases of breast cancer are diagnosed every year. Nearly 20% of these patients supplement their diets with some form of vitamin D. This high frequency of vitamin D supplement use may be due in part to research suggesting that cancer patients with higher serum vitamin D3 levels have better prognoses than patients with low serum vitamin D3. However, double-blind clinical trials on the efficacy of vitamin D3 supplementation in breast cancer have been inconclusive. A recent meta-analysis showed evidence of reduced cancer recurrence in patients taking vitamin D3 supplements who had ‘estrogen receptor positive’ (ERα66+) breast cancer, but not those who had estrogen receptor negative’ (ERα66-) breast cancer. Once ingested, vitamin D3 is metabolized in the liver into the circulating pre-hormone 25(OH)D3, which is then further metabolized into 1a,25(OH)2D3 and 24R,25(OH)2D3. 24R,25(OH)2D3 has been shown to activate a number of membrane signaling pathways, some of which overlap with 17b-estradiol (E2) signaling through ERα36, a membrane isoform of ERα66. The central hypothesis of this thesis was that 24R,25(OH)2D3 is tumorigenic in certain cancers and that this tumorigenicity is mediated in part by ERa isoforms. E2 signaling through ERa36 has been described in the ERa66-, ERa36+ breast cancer cell line HCC381. Specific aim 1 determined whether E2 signaling through ERa36 was tumorigenic other cancers with different ERa profiles. Specific aim 2 determined how 24R,25(OH)2D3 affected tumorigenicity in breast cancer using the common breast cancer cell line MCF7 (ERa66+, ERa36+) as a model. Specific aim 3 investigated the role of ERa isoforms in 24R,25(OH)2D3 signaling in breast cancer cell lines by comparing the tumorigenic effects of 24R,25(OH)2D3 in MCF7 cells (ERa66+, ERa36+) and HCC38 cells (ERa66-, ERa36+). To determine whether ERa66 regulates the effects of 24R,25(OH)2D3, ERa66 was expressed in two ERα66- cell lines. The effect of 24R,25(OH)2D3 on apoptosis was assessed in wild-type and ERa-expressing cell lines.

Food choice has intrigued generations of scholars seeking insight into the rituals that characterize the cultural and sub-cultural values of various nations and eras. Among the more recent cultural phenomena to influence theories about the body is food choice. Perhaps there is no argumentative issue more pervasive than that of food choice, because everyone must eat. The morsels that people consume are chosen as often as not for their symbolic value. A review of the literature of dietary discourse and representation reveals a gap where studies of vegetarian and vegan identity, mass media, and mass markets are concerned. This dissertation utilizes theories of representation, cultural studies, and discourse analysis to uncover culturally specific attitudes in the marketing of food with regard to vegetable-based diets, the foods that they consist of, and the people who eat them.

Human mesenchymal stem cells (MSC) have attracted a great deal of interest for their potential use in regenerative medicine and suppression of the inflammation. Nevertheless, all known therapy protocols require large amounts of MSCs, which can be obtained only by in vitro expansion. One of the most important methodological problems is associated with the use of animal-derived components in the cell culture medium. The main aim of the current research was to elucidate the influence of different serum substitutes on the proliferation, differentiation, expression of cell surface markers, and total protein expression of mesenchymal stem cells derived from human adipose tissue. In addition we were aiming to determine the features of mesenchymal stem cell populations from an exfoliated deciduous tooth (SHED) and their response to the multifunctional proinflammatory protein alpha1-antitrypsin. Our results indicate that adipose tissue derived MSCs cultivated in the presence of fetal calf serum and allogeneic human serum display similar properties, while synthetic serum substitute induces increase in growth and differentiation potential of MSCs. Moreover, our results indicate, that synthetic serum substitute also activates transcription of genes related to adipogenic and osteogenic differentiation and diminishes expression of cell surface marker CD146. In the present study, we used a proteomic approach that allowed us to compare protein expression signatures between primary cell... [to full text] / Žmogaus suaugusio organizmo mezenchiminės kamieninės ląstelės (MKL) pradėtos sėkmingai naudoti pažeistų audinių regeneracijai ir uždegiminio proceso slopinimui. Šiuolaikiniams terapijos protokolams yra reikalingi dideli ląstelių kiekiai, todėl prieš naudojimą yra būtina jas padauginti in vitro. Tačiau naudojant skirtingus MKL išskyrimo, in vitro kultivavimo ir padauginimo protokolus, yra sunku lyginti mokslinių tyrimų duomenis ir klinikinių tyrimų rezultatus. Nevienodos kultivavimo sąlygos gali įtakoti MKL funkcines savybes (augimo greitį, gebėjimą diferencijuotis, migracinį aktyvumą ir kt.). Šiame disertaciniame darbe tyrėme auginimo terpių, praturtintų skirtingais serumais (gyvulinės kilmės serumai, žmogaus alogeninis serumas, sintetinis serumas), poveikį žmogaus riebalinio audinio MKL. Taip pat charakterizavome MKL išskirtas iš žmogaus pieninių dantų pulpos ir palyginome šių ląstelių kultūros bei jų dukterinių klonų savybės. Kompleksiškai tyrėme uždegimo antiproteinazės alfa1-antitripsino (AAT) poveikį šioms ląstelėms. Nustatėme, kad, lyginant su kitais tyrime naudotais serumais, sintetinis serumo pakaitalas geriausiai skatino MKL augimą bei gebėjimą diferencijuotis adipogenine ir osteogenine kryptimis. Taip pat, skirtingai nuo kitų naudotų gyvulinės kilmės ir žmogaus serumų, sintetinis serumo pakaitalas veikė kaip adipogeninės ir osteogeninės diferenciacijos indukcijai svarbių genų PPARγ ir Msx2 transkripcijos aktyvatorius. Be to, sintetinis serumo pakaitalas slopino... [toliau žr. visą tekstą]

Background: A significant increase in the global food demand is expected to occur in the near future. Since the currently implied food system will not be able to meet this demand without impacting the environment negatively, it is crucial to consider alternative ways of producing food. Entomophagy thereby presents an approach that could be deployed to meet the future demand in an environmental and sustainable way. However, whereas multiple studies investigate consumers’ acceptance of insect-based products, little is known about their purchase intentions. Purpose: The purpose of this study is to explore the underlying factors affecting Swedish university-attending Generation Y consumers’ purchase intentions towards insect-based products. In order to fulfill the purpose of this study, two research questions have been developed. Thereby, the Theory of Planned Behavior was chosen as a theoretical framework. Method: The research philosophy of this study adopted elements of both constructionism and interpretivism. Further, this study applied an abductive approach and a qualitative research design with an exploratory purpose. A total of three focus groups were conducted in order to explore purchase intentions towards insect-based products. In addition, a taste test was incorporated in each focus group to explore the participants’ reactions when given the opportunity to try an insect-based product. To adequately reach the selected target population, a combination of a self-selection sampling technique and a convenience sampling technique was employed. Lastly, a content analysis following a directed approach was applied in order to properly analyze the collected data. Conclusion: The empirical findings of this study suggest that eleven factors are contributing to the target populations’ purchase intentions towards insect-based products. Thereby, ten of these factors are connected to the components of attitude, subjective norm, and perceived behavioral control of the theoretical framework whereas the remaining factor was not categorized within these components. Regarding the conducted taste test, it was found that the large majority of the participants were willing to try. Further, the taste test showed that all participants followed their initial intentions.

The steroid/thyroid hormone receptor superfamily is a large class of ligand-dependent transcription factors that plays a critical role in regulating the expression of genes involved in a broad range of physiological functions, including development, homeostasis, and reproduction. In the absence of cognate hormone, several receptors are able to repress transcription below the basal level via the recruitment of the nuclear receptor corepressors SMRT and NCoR. Upon hormone binding by the receptor, the corepressor complex is dissociated and a coactivator complex is subsequently recruited. This thesis details the mechanisms by which receptor-associated coactivator 3 (RAC3) interacts with nuclear receptors, particularly the vitamin D, estrogen, and retinoid receptors, and modulates their transcriptional activity. It was discovered that these receptors interact with different α-helical LXXLL motifs of RAC3 in vitro. Mutation of specific motifs differentially impairs the ability of RAC3 to enhance transcription by the receptors in vivo. In addition, the intrinsic transcriptional activation function of RAC3 was also characterized. Here, a single LXXLL motif, NR box v, was found to be essential to activation by serving as a binding surface for the general transcriptional integrator CBP/p300. Finally, the cofactor binding pocket of retinoid receptors was characterized. It was demonstrated that, to a large extent, the coactivator pocket of RARα overlaps with the corepressor pocket, with the exception of helix 12, which is required for coactivator, but not corepressor binding. Recruitment of RAC3 or SMRT also correlates directly with the ability of RARα to activate or repress transcription, respectively. Intriguingly, it was discovered that the AF-2 domain of RXRα inhibited cofactor binding to RXRα heterodimers, for deletion of this domain dramatically enhanced RAC3 and SMRT binding. In addition, it was demonstrated that the RXRα cofactor binding pocket contributed minimally to recruitment of cofactors. Conversely, the AF-2 domain of the partnering monomer and its cofactor pocket were required for these interactions. These findings suggest that the partner of RXRα is the primary docking point for cofactors at RXRα heterodimeric complexes. Taken together, this work contributes significantly to the field of nuclear receptor function in detailing the mechanisms by which the coactivator RAC3 is recruited to nuclear receptors and regulates their transcriptional activity.

The synapse is the primary locus of cell-cell communication in the nervous system. The elaboration of a functional synapse requires both a specialized structure and an efficient communication system. For my thesis work, I studied proteins implicated in each of these functions: the structural molecules dystroglycan and dystrophin, and the signaling elements Insulin Receptor Substrate p58/53 and insulin receptor. The α/β-dystroglycan complex, believed to be the heart of cellmatrix adhesion in muscle and other tissues, provides a link between dystrophin, a cytoskeletal protein at the base of the muscle cell's Dystrophin Associated Protein Complex, and the extracellular matrix. In addition, dystrophin is found at central synapses, tightly associated with the postsynaptic density. The absence of dystrophin and the secondary loss of its associated proteins causes the genetic disease Duchenne Muscular Dystrophy. DMD affects both muscle and brain, causing a severe muscular dystrophy and lower IQs than control groups. In the first portion of my thesis work, I sought to determine the role of dystroglycan, dystrophin's peripheral partner, at central synapses. I probed Northern blots of brain regions to delineate the distribution of brain β-dystroglycan mRNA and to uncover any β-dystroglycan-related transcripts in brain. Then, using subcellular brain fractions, and cultured hippocampal neurons, I determined that whereas α-dystroglycan is associated with central synapses, β-dystroglycan is not. This discovery is surprising, and differs from the finding that dystrophin and α- and β-dystroglycan colocalize at the presynaptic membrane of retinal photoreceptors. In the course of the above mentioned work, using the anti-β-dystroglycan antiserum Ab98, I discovered a pair of proteins that were tightly associated with the postsynaptic density. These polypeptides of 58 kDa and 53 kDa (p58/53) were highly enriched in postsynaptic density (PSD) fractions from rat cerebral cortex, hippocampus, and cerebellum. In pursuit of a potential synapse-specific dystroglycan relative, I purified p58 and p53 by a combination of hydrophobic interaction chromatography and two-dimensional gel electrophoresis. Mass spectroscopy and peptide microsequencing revealed that p58/53 is identical to the insulin receptor tyrosine kinase substrate p58/53 (IRSp53). Whereas IRSp58/53 has no significant homology to β-dystroglycan other than the one span of peptides that confers its antibody cross-reactivity, its localization to the PSD newly implicates insulin signaling at synapses. Analysis of IRSp58/53 mass profiles, peptides, and mRNA indicated that IRSp58 and IRSp53 are the product of the same coding sequence. Immunolocalization showed that IRSp58/53 is expressed in the synapserich molecular layer of the cerebellum. Immunostaining of cultured hippocampal neurons showed that both IRSp58/53 and insulin receptor are highly concentrated at synapses. Like IRSp58/53, insulin receptors are a component of the PSD fraction. Together, these data suggest that the synapse is a specialized site for insulin signaling in the brain.

One important objective of prostate cancer (PCa) research is to understand the molecular basis underlying the progression of these cancers from an androgen dependent to an androgen independent state. Hypermethylation of the promoter CpG islands is associated with the transcriptional silencing of specific gene sets in each tumor type and subtype. Transcriptional silencing of antitumor genes via CpG island hypermethylation could be a mechanism mediating PCa progression from an androgen-dependent to an androgen-independent state. Hypermethylation associated gene silencing has been reported for a great number of genes in PCa with the exception of the genes that undergo methylation associated silencing specifically during cancer development to androgen independence. The first aim of this thesis is to identify novel glenes which undergo DNA hypermethylation associated gene silencing during the cancer progression. The androgen-dependent (AD, as defined as the inability of celill to proliferate in the absence of androgen) PCa cell line LNCaP gives rise to the androgen-independent (AI) subline LNCaPcs generated by maintaining LNCaP in medium with charcoal-stripped (CS) serum for over 30 passages. This LNCaP cell model was used to identify differentially methylated sequences between the two genomes using the Methylation-Sensitive Restriction Fingerprinting (MSRF) technique. One sequence identified is located in a 5' CpG island, which encompasses part of the promoter, exon 1, and part of intron 1, of the Peroxisomal Membrane Protein 24 KD (PMP24) gene. PMP24 is silenced in concert with the hypermethylation of its CpG island in AI LNCaPcsand PC-3 cell lines. The silencing is reactivated by the treatment with a DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine (5AZAdC). PMP24 is specifically silenced in PCa cancer cell lines and shows potential antitumor properties. These results demonstrate the utility of MSRF in the identification of novel, differentially methylated DNA sequences in the genome and suggest that hypermethylation-mediated silencing of PMP24 is an epigenetic event involved in PCa progression to androgen independence. The next study investigated the molecular mechanism for DNA methylation associated gene silencing of PMP24 in AI LNCaPcs and PC-3 cell lines. We demonstrated that PMP24 transcription is repressed by the disruption of transcription factor binding to a critical cis-element by hypermethylation of its promoter CpG island. We found a CpG containing activator protein 2 (AP-2) cis-element in the intron 1 of PMP24 whose first CpG dinucleotidle is essential for the sequence-specific protein binding and the promoter activity of the gene. We presented first in cellulo evidence that the methylation of AP-2 cis-element alone but not the whole CpG island, using a newly developed methylated oligonucleotides treatment, is sufficient for the downregulation of PMP24. Our study is the first to report that the silencing mechanism for PMP24 in AI LNCaPcs and PC-3 is mediated by the complete methylation of a single GpG site of AP-2 cis-element in the intron 1 part of the CpG island, which interferes with transcription factor binding. Most interestingly, the promoter CpG island of PMP24 is hypermethylated in AD LNCaP cells with the incomplete methylation specifically at the AP-2 cis-element. The silencing of PMP24 in AD LNCaP cells was reactivated not by the 5AZAdC treatment but by the treatment with Trichostatin A (TSA), a histone deacetylase inhibitor. An alternative silencing mechanism for PMP24 other than the interference with transcription factor binding by methylation is therefore likely involved at this androgen-dependent stage. During the androgen ablation process, this mechanism is either evolved by the spread of methylation in the promoter CpG island or selected against, leading to the methylation-dominant silencing mechanism in the AI cells as seen in LNCaPcsand PC-3 cells. Taken together, this thesis emphasized the important role of DNA methylation in the progression of PCa into androgen independence. Particular respect should be paid to the specific CpG dinucleotides in cis-elements critical for the promoter activity, whose complete methylation could dominate the silencing mechanism which is independent of androgen. This thesis also pointed to the importance of monitoring the effects of cell culture on the methylation status of genes. Most importantly, this thesis raised the possibility that the silencing mechanisms for PMP24 could be different in AD LNCaP cells as compared to AI LNCaPcs and PC-3 cells. Either the evolution of such mechanism or the selectivity against it during the androgen ablation process would result in a methylation-dominant silencing mechanism of the genes such as PMP24 in AI cells and may contribute to the overall androgen independence of the cells.

The insulin/IGF-1 signaling pathway plays a pivotal role in life span regulation in diverse organisms. In Caenorhabditis elegans, a PI 3-kinase signaling cascade downstream of DAF-2, an ortholog of the mammalian insulin and insulin-like growth factor-1 (IGF-1) receptor, negatively regulates DAF-16/forkhead transcription factor. DAF-16 then regulates a wide variety of genes involved in longevity, stress response, metabolism and development. DAF-16 also receives signals from other pathways regulating life span and development. However, the precise mechanism by which DAF-16 directs multiple functions is poorly understood. First, in Chapter II, we demonstrate that JNK is a novel positive regulator of DAF-16 in both life span regulation and stress resistance. Our genetic analysis suggests that the JNK pathway acts in parallel with the insulin-like signaling pathway to regulate life span and both pathways converge onto DAF-16. We also show that JNK-1 directly interacts with and phosphorylates DAF-16. Moreover, in response to heat stress, JNK-1 promotes the translocation of DAF-16 into thc nucleus. Our findings define a novel interaction between the stress response pathway (JNK) and the master regulator of life span (DAF-16), and provide a mechanism by which JNK regulates longevity and stress resistance. Next, in Chapter III, we focus on the downstream targets of DAF-16. Here, we used a modified chromatin immunoprecipitation (ChIP) method to identify direct target promoters of DAF-16. We cloned 103 target sequences containing consensus DAF-16 binding sites and randomly selected 33 targets for further analysis. The expression of majority of these genes is regulated in a DAF-16-dependent manner. Moreover, inactivation of more than 50% of these genes significantly altered DAF-16-dependent functions such as longevity, fat storage and dauer diapause. Our results show that the ChIP-based cloning strategy leads to greater enrichment of DAF-16 target genes, compared to previous studies using DNA micro array or bioinformatics. We also demonstrate that DAF-16 is recruited to multiple promoters to coordinate regulation of its downstream target genes. In summary, we identified the JNK signaling pathway as a novel input into DAF-16 to adapt animals to the environmental stresses. We also revealed a large number of novel outputs of DAF-16. Taken together, these studies provide insight into the complex regulation by DAF-16 to control diverse biological functions and eventually broaden our understanding of aging.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aims to analyze the performance of Brazilian exports, disaggregated by aggregate factor (Basic, Semi-manufactured and Manufactured), to Asia and Trade Partners NAFTA and the European Union, based on monthly data for the period January 1999 to June 2013. For this, were identified based on theoretical grounds, the main determinants and, through statistical tools, equations of short and long run for Brazilian sector exports were estimated, so that they could evaluate the elasticities quantum exported from the country. Still, were analyzed the performance and structure of Brazilian exports sector, their relationships with selected trade partners as well as their participation in world trade. For this, from an extension of the traditional theoretical model of imperfect substitutes, elaborated by Goldstein and Khan (1978), we use the method of Johansen cointegration and Error Correction Model (ECM) for determining the elasticities. Through the traditional literature of foreign trade, it was inferred that the determinants of exports are pegged to an index of income from trading partners, to index relative price of exports and the exchange rate. The results showed that the elasticities are greater than the long term to short term. Facing the sectorial impacts, the elasticities of trade with Asia and NAFTA show that the class of basic goods is more sensitive to income, while the other classes are more sensitive to exchange rate variations. On the other hand, exports to the European Union, income is the main determinant of the classes of manufactured and semimanufactured goods, while basics goods are more sensitive to exchange rates. In reference to average sectorial elasticities, one can say that income is the main determinant of basic products exports, while the classes of semi-manufactured and manufactured goods are more sensitive to changes in price levels. Finally, the negative effect of exchange rate volatility, verified is be a dynamic mainly short run. / O presente estudo tem como objetivo analisar o desempenho das exportações brasileiras, desagregadas por fator agregado (Básicos, Semimanufaturados e Manufaturados), para a Ásia e os Blocos Econômicos Nafta e União Europeia, a partir de dados mensais para o período de janeiro de 1999 a junho de 2013. Para isso, foram identificados, com base nos fundamentos teóricos, os principais determinantes e, através do ferramental estatístico, foram estimadas equações de curto e longo prazo para as exportações setoriais brasileiras, para que se pudesse avaliar as elasticidades do quantum exportado do país. Ainda, foram analisados o desempenho e a estrutura das exportações setoriais brasileiras, suas relações com os parceiros comerciais selecionados, bem como sua participação no comércio mundial. Para tanto, a partir de uma extensão do tradicional modelo teórico de substitutos imperfeitos, elaborado por Goldstein e Khan (1978), utiliza-se o método de cointegração de Johansen e o Modelo de Correção de Erros (ECM) para a determinação das elasticidades. Através da literatura tradicional de comércio exterior, inferiu-se que os determinantes das exportações estão atrelados a um índice de renda dos parceiros comerciais, ao índice de preço relativo das exportações e a taxa de câmbio. Os resultados mostraram que as elasticidades de longo prazo são superiores às de curto prazo. Frente aos impactos setoriais, as elasticidades do comércio com a Ásia e o Nafta mostram que a classe de produtos básicos é mais sensível à renda, enquanto que as demais classes são mais sensíveis às variações cambiais. Por outro lado, nas exportações para a União Europeia, a renda é o principal determinante das classes de manufaturados e semimanufaturados, enquanto que os produtos básicos são mais sensíveis ao câmbio. Em referência às elasticidades setoriais médias, pode-se dizer que a renda é o principal determinante das exportações de produtos básicos, enquanto que as classes de semimanufaturados e manufaturados são mais sensíveis às variações dos níveis de preços. Por fim, quanto ao impacto negativo da volatilidade cambial, verificou-se ser uma dinâmica, principalmente, de curto prazo.

Introdução: A busca por um substituto ósseo que faça prescindível a obtenção de enxerto autólogo é uma necessidade do cirurgião ortopédico. O aspirado de medular óssea possui células tronco do sistema mesenquimal capazes de se diferenciarem em osteoblastos, sendo assim considerado um material osteogênico. O plasma rico em plaquetas possui os chamados fatores plaquetários de crescimento, que possuem a capacidade de promover e estimular a diferenciação de células tronco do sistema mesenquimal em osteoblastos, acelerando o processo de consolidação óssea. Objetivo: O objetivo deste estudo foi avaliar a ocorrência de consolidação e o tempo para tal nas osteotomias de cunha de abertura na tíbia, comparando o enxerto autólogo de ilíaco, ao plasma rico em plaquetas associado a medular óssea. Métodos: Foram estudados 25 pacientes submetidos a osteotomia tibial de cunha de abertura medial. Os pacientes foram divididos em dois grupos, de forma randomizada. O grupo controle formado por 14 pacientes submetidos à osteotomia com a utilização de enxerto autólogo do ilíaco, e o grupo de estudo formado por 11 pacientes submetidos à osteotomia com utilização de um composto de plasma rico em plaquetas e medular óssea. Resultados: Quanto à ocorrência de consolidação da osteotomia, as Introdução: A busca por um substituto ósseo que faça prescindível a obtenção de enxerto autólogo é uma necessidade do cirurgião ortopédico. O aspirado de medular óssea possui células tronco do sistema mesenquimal capazes de se diferenciarem em osteoblastos, sendo assim considerado um material osteogênico. O plasma rico em plaquetas possui os chamados fatores plaquetários de crescimento, que possuem a capacidade de promover e estimular a diferenciação de células tronco do sistema mesenquimal em osteoblastos, acelerando o processo de consolidação óssea. Objetivo: O objetivo deste estudo foi avaliar a ocorrência de consolidação e o tempo para tal nas osteotomias de cunha de abertura na tíbia, comparando o enxerto autólogo de ilíaco, ao plasma rico em plaquetas associado a medular óssea. Métodos: Foram estudados 25 pacientes submetidos a osteotomia tibial de cunha de abertura medial. Os pacientes foram divididos em dois grupos, de forma randomizada. O grupo controle formado por 14 pacientes submetidos à osteotomia com a utilização de enxerto autólogo do ilíaco, e o grupo de estudo formado por 11 pacientes submetidos à osteotomia com utilização de um composto de plasma rico em plaquetas e medular óssea. Resultados: Quanto à ocorrência de consolidação da osteotomia, asIntrodução: A busca por um substituto ósseo que faça prescindível a obtenção de enxerto autólogo é uma necessidade do cirurgião ortopédico. O aspirado de medular óssea possui células tronco do sistema mesenquimal capazes de se diferenciarem em osteoblastos, sendo assim considerado um material osteogênico. O plasma rico em plaquetas possui os chamados fatores plaquetários de crescimento, que possuem a capacidade de promover e estimular a diferenciação de células tronco do sistema mesenquimal em osteoblastos, acelerando o processo de consolidação óssea. Objetivo: O objetivo deste estudo foi avaliar a ocorrência de consolidação e o tempo para tal nas osteotomias de cunha de abertura na tíbia, comparando o enxerto autólogo de ilíaco, ao plasma rico em plaquetas associado a medular óssea. Métodos: Foram estudados 25 pacientes submetidos a osteotomia tibial de cunha de abertura medial. Os pacientes foram divididos em dois grupos, de forma randomizada. O grupo controle formado por 14 pacientes submetidos à osteotomia com a utilização de enxerto autólogo do ilíaco, e o grupo de estudo formado por 11 pacientes submetidos à osteotomia com utilização de um composto de plasma rico em plaquetas e medular óssea. Resultados: Quanto à ocorrência de consolidação da osteotomia, as Introdução: A busca por um substituto ósseo que faça prescindível a obtenção de enxerto autólogo é uma necessidade do cirurgião ortopédico. O aspirado de medular óssea possui células tronco do sistema mesenquimal capazes de se diferenciarem em osteoblastos, sendo assim considerado um material osteogênico. O plasma rico em plaquetas possui os chamados fatores plaquetários de crescimento, que possuem a capacidade de promover e estimular a diferenciação de células tronco do sistema mesenquimal em osteoblastos, acelerando o processo de consolidação óssea. Objetivo: O objetivo deste estudo foi avaliar a ocorrência de consolidação e o tempo para tal nas osteotomias de cunha de abertura na tíbia, comparando o enxerto autólogo de ilíaco, ao plasma rico em plaquetas associado a medular óssea. Métodos: Foram estudados 25 pacientes submetidos a osteotomia tibial de cunha de abertura medial. Os pacientes foram divididos em dois grupos, de forma randomizada. O grupo controle formado por 14 pacientes submetidos à osteotomia com a utilização de enxerto autólogo do ilíaco, e o grupo de estudo formado por 11 pacientes submetidos à osteotomia com utilização de um composto de plasma rico em plaquetas e medular óssea. Resultados: Quanto à ocorrência de consolidação da osteotomia, as Introdução: A busca por um substituto ósseo que faça prescindível a obtenção de enxerto autólogo é uma necessidade do cirurgião ortopédico. O aspirado de medular óssea possui células tronco do sistema mesenquimal capazes de se diferenciarem em osteoblastos, sendo assim considerado um material osteogênico. O plasma rico em plaquetas possui os chamados fatores plaquetários de crescimento, que possuem a capacidade de promover e estimular a diferenciação de células tronco do sistema mesenquimal em osteoblastos, acelerando o processo de consolidação óssea. Objetivo: O objetivo deste estudo foi avaliar a ocorrência de consolidação e o tempo para tal nas osteotomias de cunha de abertura na tíbia, comparando o enxerto autólogo de ilíaco, ao plasma rico em plaquetas associado a medular óssea. Métodos: Foram estudados 25 pacientes submetidos a osteotomia tibial de cunha de abertura medial. Os pacientes foram divididos em dois grupos, de forma randomizada. O grupo controle formado por 14 pacientes submetidos à osteotomia com a utilização de enxerto autólogo do ilíaco, e o grupo de estudo formado por 11 pacientes submetidos à osteotomia com utilização de um composto de plasma rico em plaquetas e medular óssea. Resultados: Quanto à ocorrência de consolidação da osteotomia, as porcentagens de consolidação foram de 100% no grupo Ilíaco e 91% no grupo PRP (p=0,440). Em relação ao tempo para consolidação não se observou diferença entre os grupos (p=0,129). Conclusão: Nas osteotomias proximais por cunha de adição medial a utilização do plasma rico em plaquetas associado ao aspirado de medular óssea foi efetiva no que se refere à ocorrência de consolidação e no tempo necessário para a ocorrência de tal evento, quando estudamos e comparamos este enxerto ao enxerto autólogo do ilíaco / Introduction: The search for a bone substitute that makes unnecessary the harvest of autologous bone graft is a necessity of the orthopaedic surgeon. Bone marrow aspirate is rich in mesenquimal stem cells. The bone marrow aspirate contain mesenquimal stem cells that can differenciate in osteoblasts, being considered an osteogenic material. Platelet rich plasma contain several growth factors that have the capacity to promote and stimulate the differenciation of mesenquimal stem cells in osteoblasts improving the bone healing process, in other words platelet rich plasma has osteoinductive property. Objective: The aim of this study was to compare the occurrence of consolidation and the time taken to achieve this in cases of opening wedge osteotomy of the tibia, between autologous iliac grafts and platelet rich plasma with bone marrow aspirate. Methods: Twenty-five patients who underwent opening wedge osteotomy were studied. They were randomly divided into two groups: a control group of 14 patients wich received autologous iliac grafts and a study group of 11 patients wich received a compound of platelet rich plasma and bone marrow aspirate. Results: The consolidation rates achieved were 100% in the iliac group and 91% in the platelet-rich plasma group (p = 0.440). There was no difference in the time taken to achieve consolidation between the groups (p = 0.129). Conclusion: The use of platelet rich plasma with bone marrow aspirate as a bone substitute was shown to be effective in achieving consolidation in tibial osteotomies and in the time necessary to achieve this when compared to autologous iliac graft .