Indiana University-Purdue University Indianapolis (IUPUI) / Resveratrol has been shown to inhibit cell growth and induce apoptosis, as well as augment chemotherapeutics and irradiation in multiple cancer types. However, it is unknown if resveratrol is beneficial for treating drug-resistant cancer cells. To study the effects of resveratrol in triple negative breast cancer cells that are resistant to the common cancer drug, paclitaxel, a novel paclitaxel-resistant cell line was generated from the MDA-MB-231 breast cancer cell line. The resulting cell line, MDA-MB-231/PacR, exhibited a 12-fold increased resistance to paclitaxel but remained sensitive to resveratrol treatment. Resveratrol treatment reduced cell proliferation and colony formation and increased senescence and apoptosis in both the parental MDA-MB-231 and MDA-MB-231/PacR cell lines. Importantly, resveratrol treatment augments the effects of paclitaxel in both cell lines. The expression of the drug efflux transporter gene, MDR1, and the main metabolizing enzyme of paclitaxel gene, CYP2C8, was increased in the resistant cells. Moreover, pharmacological inhibition of the protein products of these genes, P-glycoprotein and CYP2C8, decreased paclitaxel resistance in the resistant but not in the parental cells, which suggests that the increase of these proteins are important contributors to the resistance of these cells. In conclusion, these studies imply that resveratrol, both alone and in combination with paclitaxel, may be useful in the treatment of paclitaxel-sensitive and paclitaxel-resistant triple negative breast cancers.

Indiana University-Purdue University Indianapolis (IUPUI) / MicroRNAs are small RNA molecules that regulate expression of genes involved in development, cell differentiation, proliferation and death. It has been estimated that in eukaryotes, approximately 0.5 to 1% of predicted genes encode a microRNA, which in humans, regulate at least 30% of genes at an average of 200 genes per miRNA. Some microRNAs are tissue-specific, while others are ubiquitously expressed. In liver, a few microRNAs have been identified that regulate specialized functions. The best known is miR-122, the most abundant liver-specific miRNA, which regulates cholesterol biosynthesis and other genes of fatty acid metabolism; it also regulates the cell cycle through inhibition of cyclin G1. To discover other miRNAs with relevant function in liver, we characterized miRNA profiles in normal tissue and identified miR-709. Our data indicates this is a highly abundant hepatic miRNA and is dysregulated in an animal model of type 2 diabetes. To understand its biological role, miR-709 gene targets were identified by analyzing the transcriptome of primary hepatocytes transfected with a miR-709 mimic. The genes identified fell within four main categories: cytoskeleton binding, extracellular matrix attachment, endosomal recycling and fatty acid metabolism. Thus, similar to miR-122, miR-709 downregulates genes from multiple pathways. This would be predicted, given the abundance of the miRNA and the fact that the estimated number of genes targeted by a miRNA is in the hundreds. In the case of miR-709, these suggested a coordinated response during cell proliferation, when cytoskeleton remodeling requires substantial changes in gene expression. Consistently, miR-709 was found significantly upregulated in an animal model of hepatocellular carcinoma. Likewise, in a mouse model of liver regeneration, mature miR-709 was increased. To study the consequences of depleting miR-709 in quiescent and proliferating cells, primary hepatocytes and hepatoma cells were cultured with antagomiRs (anti-miRs). The presence of anti-miR-709 caused cell death in proliferating cells. Quiescent primary hepatocytes responded by upregulating miR-709 and its host gene, Rfx1. These studies show that miR-709 targets genes relevant to cystokeleton structural genes. Thus, miR-709 and Rfx1 may be needed to facilitate cytoskeleton reorganization, a process that occurs after liver injury and repopulation, or during tumorigenesis.

Indiana University-Purdue University Indianapolis (IUPUI) / Dicalcium phosphate dihydrate (DCPD) cements have been used for bone repair due to its excellent biocompatibility and resorbability. However, DCPD cements are typically weak and brittle. To overcome these limitations, the sodium citrate used as a setting regulator and the coating of poly-L-lactide acid (PLLA) technique have been proposed in this study. The first purpose of this thesis is to develop composite PLLA/DCPD scaffolds with enhanced toughness by PLLA coating. The second purpose is to examine the biocompatibility of the scaffolds. The final purpose is to investigate the degradation behaviors of DCPD and PLLA/DCPD scaffolds. In this experiment, DCPD cements were synthesized from monocalcium phosphate monohydrate (MCPM) and 𝛽-tricalcium phosphate (𝛽 –TCP) by using deionized water and sodium citrate as liquid components. The samples were prepared with powder to liquid ratio (P/L) at 1.00, 1.25 and 1.50. To fabricate the PLLA/DCPD composite samples, DCPD samples were coated with 5 % PLLA. The samples were characterized mechanical properties, such as porosity, diametral tensile strength, and fracture energy. The mechanical properties of DCPD scaffolds with and without PLLA coating after the in vitro static degradation (day 1, week1, 4, and 6) and in vitro dynamic degradation (day 1, week 1, 2, 4, 6, and 8) were investigated by measuring their weight loss, fracture energy, and pH of phosphate buffer solution. In addition, the dog bone marrow stromal stem cells (dBMSCs) adhesion on DCPD and PLLA/DCPD composite samples were examined by scanning electron microscopy. The cell proliferation and differentiation in the medium conditioned with DCPD and PLLA/DCPD composite samples were studied by XTT (2,3-Bis(2-methoxy-4- nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide inner salt), and alkaline phosphatase (ALP) assay, respectively. The addition of sodium citrate and PLLA coating played a crucial role in improving the mechanical properties of the samples by increasing the diametral tensile strength from 0.50 ± 0.15 MPa to 2.70 ± 0.54 MPa and increasing the fracture energy from 0.76 ± 0.18 N-mm to 12.67 ± 4.97 N-mm. The DCPD and PLLA/DCPD composite samples were compatible with dBMSCs and the cells were able to proliferate and differentiate in the conditioned medium. The degradation rate of DCPD and PLLA/DCPD samples were not significant different (p > 0.05). However, the DCPD and PLLA/DCPD composite samples those used sodium citrate as a liquid component was found to degrade faster than the groups that use deionized water as liquid component

Indiana University-Purdue University Indianapolis (IUPUI) / Approximately 2.8% of the world population is currently infected with hepatitis C virus (HCV). Neutralizing antibodies (nAbs) are often generated in chronic hepatitis C patients yet fail to control the infection. In the first two chapters of this study, we focused on two alternative routes of HCV transmission, which may contribute to HCV’s immune evasion and establishment of chronic infection. HCV was transmitted via a cell-cell contact-mediated (CCCM) route and in the form of exosomes. Formation of HCV infection foci resulted from CCCM HCV transfer and was cell density-dependent. Moreover, CCCM HCV transfer occurred rapidly, involved all four known HCV receptors and intact actin cytoskeleton, and led to productive HCV infection. Furthermore, live cell imaging revealed the temporal and spatial details of the transfer process. Lastly, HCV from HCV-infected hepatocytes and patient plasma occurred in both exosome-free and exosome-associated forms and the exosome-associated HCV remained infectious, even though HCV infection did not significantly alter exosome secretion. In the third chapter, we characterized HCV interaction with astrocytes, one of the putative HCV target cells in the brain. HCV infection causes the central nervous system (CNS) abnormalities in more than 50% of chronically infected subjects but the underlying mechanisms are largely unknown. We showed that primary human astrocytes (PHA) were very inefficiently infected by HCV, either in the free virus form or through cell-cell contact. PHA expressed all known HCV receptors but failed to support HCV entry. HCV IRES-mediated translation was functional in PHA and further enhanced by miR122 expression. Nevertheless, PHA did not support HCV replication regardless of miR122 expression. To our great surprise, HCV exposure induced robust IL-18 expression in PHA and exhibited direct neurotoxicity. In summary, we showed that CCCM HCV transfer and exosome-mediated HCV infection constituted important routes for HCV infection and dissemination and that astrocytes did not support productive HCV infection and replication, but HCV interactions with astrocytes and neurons alone might be sufficient to cause CNS dysfunction. These findings provide new insights into HCV infection of hepatocytes and astrocytes and shall aid in the development of new and effective strategies for preventing and treating HCV infection.

The South African education system is in crisis; with low matric pass rates, high dropout rates, teacher strikes, rising pregnancy rates among teenaged learners, and assaults by learners on educators and other learners. The system is unable to cope with the multiple demands placed on it and a number of NGOs are stepping in to aid the system. This study is an evaluation of an NGO aimed at developing learners through the application of the Appreciative Inquiry approach. The Appreciative Inquiry approach is a method for generating change within an organisation by looking at what works in the organisation and facilitating active participation. The main findings from this study were that the programme seems to have positively affected learners‟ performance both academically and behaviourally; the programme was perceived to have raised the general standard of academic performance at the school. / Psychology / M.A. (Psychology)

Submitted by admin tede (tede@pucgoias.edu.br) on 2016-09-02T17:40:18Z No. of bitstreams: 1 CELIA ALVES DE LELES.pdf: 1521803 bytes, checksum: cd3e757bb2130fa009ac8627748b5353 (MD5) / Made available in DSpace on 2016-09-02T17:40:18Z (GMT). No. of bitstreams: 1 CELIA ALVES DE LELES.pdf: 1521803 bytes, checksum: cd3e757bb2130fa009ac8627748b5353 (MD5) Previous issue date: 2015-12-10 / The study aims to investigate questions that hinder the growth of small HEIs (Higher Education Institutions). Through field research and institutional evaluation, we sought to compare the results obtained in an evaluation process in the academic community and local, interpreting the reality of small IES-private, located in the interior of Goiás, FAIT (Alliance School), there are 07 (seven) years operates in the field of higher education, as PMIES, with an approximate capacity of 300 students enrolled. This paper compares the standards and guidelines of the National Assessment of Higher Education Institutions System - SINAES / CONAES, from the data collected and analysis by research conducted by ABMES, between the years 2013-2014, and by analysis of research authors like Ristoff and Sobrinho. The analysis began with the lifting of qualitative comparative profile, matching the CPA's (committee for assessment) internal and external of the same HEI (2013), as well as bibliographic data and documentaries, which provided the mapping references and the reality of small private institution in the city of Itaberaí. Then made up his own field research HEIs (Higher Education Institutions) in 2014, through a detailed, organized that provided the search suggestions, projects as alternative to improve the competitiveness of private small IES and midsize, research object. And, based on field research, completed the CPA (internal) in March and April 2013, analyzed the reality of small HEIs (Higher Education Institutions) and the observation of its influence in the IDH (Índice de Desenvolvimento Humano) (Index Human Development) site. The field research addressed together: the questionnaire, application of complementary interviews by CATI methodology (by telephone) and individually, the representatives of the local community, students and alumni of FAIT (Alliance College); already Institutional Evaluation was carried out by the online system through Web Survey, students and employees FAIT (Alliance College). At first, we tried to understand the reality and the assessment of the scenario of Brazilian higher education in relation to research and the actual phase is the establishment of the small college, in the city and region, higher education institution located in the Central region west Goiano. The results achieved in small IES-FAIT, when comparing to research presented by ABMEIS (2013) suggest greater care and support the permanence of small private HEIs in the municipalities, which are installed in view of the importance of these in the IDH (Índice de Desenvolvimento Humano) (Index Human development), despite the financial difficulties they face. For it is clear the influence of PMIES (Small and Medium Higher Education Institution) to local and regional development, with a tendency to increase per capita income and economic of each region, where they are installed. / O estudo tem como propósito investigar quesitos que dificultam o crescimento das pequenas IES (Instituições de Ensino Superior). Através de uma pesquisa de campo e avaliação institucional, buscamos comparar os resultados apurados em um processo avaliativo junto à comunidade acadêmica e local, interpretando a realidade da pequena IES-privada, situada no interior de Goiás, FAIT (Faculdade Aliança), que há 07 (sete) anos atua no ramo do Ensino Superior, como PMIES, com capacidade aproximada para 300 alunos matriculados. O presente trabalho compara as normas e diretrizes do Sistema Nacional de Avaliação das Instituições de Ensino Superior – SINAES/CONAES, a partir dos dados e análises levantados, por pesquisa realizada pela ABMES, entre os anos de 2013-2014, e mediante análise das pesquisas de autores como Ristoff e Sobrinho. A análise iniciou com o levantamento do perfil comparativo qualitativa, combinando com a CPA´s (Comissão Própria de Avaliação) interna e externa da mesma IES (2013), assim como de dados bibliográficos e documentários, que proporcionaram o mapeamento e referências da realidade da pequena IES privada, no município de Itaberaí. Em seguida fez-se a pesquisa de campo da própria IES (Instituições de Ensino Superior), em 2014, através de uma análise detalhada, organizada que proporcionou a busca de sugestões, projetos como alternativos para a melhoria da competitividade da IES privada de pequeno e médio porte, objeto de pesquisa. E, com base na pesquisa de campo, completada com a CPA (interna), em março e abril de 2013, analisou-se a realidade da pequena IES (Instituições de Ensino Superior), bem como a observação de sua influência no IDH (Índice de Desenvolvimento Humano) local. A pesquisa de campo abordou em conjunto: à aplicação de questionário, aplicação de entrevistas complementares por meio da metodologia CATI (por telefone) e individualmente, a representantes da comunidade local, alunos e ex-alunos da FAIT (Faculdade Aliança); já a Avaliação Institucional foi realizada pelo sistema on-line, através de Web Survey, aos alunos e funcionários da FAIT (Faculdade Aliança). A princípio, buscou-se compreender a realidade e o cenário da avaliação da Educação Superior brasileira no que se refere à pesquisa e a real fase que constitui o estabelecimento da pequena Faculdade, no município e região, instituição de ensino superior localizada na região do Centro Oeste-Goiano. Os resultados realizados na pequena IES-FAIT, ao comparar com a pesquisa apresentada pela ABMEIS (2013) sugerem maior cuidado e apoio a permanência das pequenas IES privadas, nos municípios, que estão instaladas, tendo em vista a importância dessas no IDH (Índice de Desenvolvimento Humano), mesmo diante das dificuldades financeiras que enfrentam. Pois, é nítida a influência das PMIES (Pequena e Média Instituição de Ensino Superior) ao desenvolvimento local e regional, com tendência a aumentar a renda per capita e econômica de cada região, a onde estão instaladas.

The South African education system is in crisis; with low matric pass rates, high dropout rates, teacher strikes, rising pregnancy rates among teenaged learners, and assaults by learners on educators and other learners. The system is unable to cope with the multiple demands placed on it and a number of NGOs are stepping in to aid the system. This study is an evaluation of an NGO aimed at developing learners through the application of the Appreciative Inquiry approach. The Appreciative Inquiry approach is a method for generating change within an organisation by looking at what works in the organisation and facilitating active participation. The main findings from this study were that the programme seems to have positively affected learners‟ performance both academically and behaviourally; the programme was perceived to have raised the general standard of academic performance at the school. / Psychology / M.A. (Psychology)

Indiana University-Purdue University Indianapolis (IUPUI) / Hydrogels prepared from photopolymerization have been used for a variety of tissue engineering and controlled release applications. Polymeric biomaterials with high cytocompatibility, versatile degradation behaviors, and diverse material properties are particularly useful in studying cell fate processes. In recent years, step-growth thiol-ene photochemistry has been utilized to form cytocompatible hydrogels for tissue engineering applications. This radical-mediated gelation scheme utilizes norbornene functionalized multi-arm poly(ethylene glycol) (PEGNB) as the macromer and di-thiol containing molecules as the crosslinkers to form chemically crosslinked hydrogels. While the gelation mechanism was well-described in the literature, the network properties and degradation behaviors of these hydrogels have not been fully characterized. In addition, existing thiol-ene photopolymerizations often used type I photoinitiators in conjunction with an ultraviolet (UV) light source to initiate gelation. The use of cleavage type initiators and UV light often raises biosafety concerns. The first objective of this thesis was to understand the gelation and degradation properties of thiol-ene hydrogels. In this regard, two types of step-growth hydrogels were compared, namely thiol-ene hydrogels and Michael-type addition hydrogels. Between these two step-growth gel systems, it was found that thiol-ene click reactions formed hydrogels with higher crosslinking efficiency. However, thiol-ene hydrogels still contained significant network non-ideality, demonstrated by a high dependency of hydrogel swelling on macromer contents. In addition, the presence of ester bonds within the PEGNB macromer rendered thiol-ene hydrogels hydrolytically degradable. Through validating model predictions with experimental results, it was found that the hydrolytic degradation of thiol-ene hydrogels was not only governed by ester bond hydrolysis, but also affected by the degree of network crosslinking. In an attempt to manipulate network crosslinking and degradation rate of thiol-ene hydrogels, different macromer contents and peptide crosslinkers with different amino acid sequences were used. A chymotrypsin-sensitive peptide was also used as part of the hydrogel crosslinkers to render thiol-ene hydrogels enzymatically degradable. The second objective of this thesis was to develop a visible light-mediated thiol-ene hydrogelation scheme using a type II photoinitiator, eosin-Y, as the only photoinitiator. This approach eliminates the incorporation of potentially cytotoxic co-initiator and co-monomer that are typically used with a type II initiator. In addition to investigating the gelation kinetics and properties of thiol-ene hydrogels formed by this new gelation scheme, it was found that the visible light-mediated thiol-ene hydrogels were highly cytocompatible for human mesenchymal stem cells (hMSCs) and pancreatic MIN6 beta-cells. It was also found that eosin-Y could be repeatedly excited for preparing step-growth hydrogels with multilayer structures. This new gelation chemistry may have great utilities in controlled release of multiple sensitive growth factors and encapsulation of multiple cell types for tissue regeneration.

Indiana University-Purdue University Indianapolis (IUPUI) / The Lyme disease agent, Borrelia burgdorferi, has a complex system that allows it to thrive in the harsh and distinct environments of its tick vector and mammalian host. Although it has been known for some time that the Borrelia oxidative stress regulator protein (BosR) plays a necessary role in mammalian infectivity and functions as a transcriptional regulator of alternative sigma factor RpoS, very little is known about its mechanism of action, other than the suggestion that BosR activates rpoS transcription by binding to certain upstream regions of the gene. In our studies, we performed protein degradation assays and luciferase reporter assays for further understanding of BosR function. Our preliminary findings suggest that BosR is post-transcriptionally regulated by an unknown protease and may not need to bind to any rpoS upstream regions in order to activate transcription. We also describe the construction of luciferase reporter systems that will shed light on BosR’s mechanism of action. We postulate the provocative possibility that unlike its homologs Fur and PerR in other bacterial systems, BosR may not utilize a DNA-binding mechanism in order to fulfill its role as a transcriptional regulator to modulate virulence gene expression.

Indiana University-Purdue University Indianapolis (IUPUI) / Robustness and generalizability of supervised learning algorithms depend on the quality of the labeled data set in representing the real-life problem. In many real-world domains, however, we may not have full knowledge of the underlying data-generating mechanism, which may even have an evolving nature introducing new classes continually. This constitutes a partially-observed setting, where it would be impractical to obtain a labeled data set exhaustively defined by a fixed set of classes. Traditional supervised learning algorithms, assuming an exhaustive training library, would misclassify a future sample of an unobserved class with probability one, leading to an ill-defined classification problem. Our goal is to address situations where such assumption is violated by a non-exhaustive training library, which is a very realistic yet an overlooked issue in supervised learning. In this dissertation we pursue a new direction for supervised learning by defining self-adjusting models to relax the fixed model assumption imposed on classes and their distributions. We let the model adapt itself to the prospective data by dynamically adding new classes/components as data demand, which in turn gradually make the model more representative of the entire population. In this framework, we first employ suitably chosen nonparametric priors to model class distributions for observed as well as unobserved classes and then, utilize new inference methods to classify samples from observed classes and discover/model novel classes for those from unobserved classes. This thesis presents the initiating steps of an ongoing effort to address one of the most overlooked bottlenecks in supervised learning and indicates the potential for taking new perspectives in some of the most heavily studied areas of machine learning: novelty detection, online class discovery and semi-supervised learning.