Amine functionalization of cholecyst-derived extracellular matrix with generation 1 PAMAM dendrimer

This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Biomacromolecules, copyright © American Chemical Society after peer review. To access the final edited and published work, see http://pubs.acs.org/doi/pdf/10.1021/bm701055k.A method to functionalize cholecyst-derived extracellular matrix (CEM) with free amine groups was established in an attempt to improve its potential for tethering of bioactive molecules. CEM was incorporated with Generation-1 polyamidoamine (G1 PAMAM) dendrimer by using N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide and N-hydroxysuccinimide cross-linking system. The nature of incorporation of PAMAM dendrimer was evaluated using shrink temperature measurements, Fourier transform infrared (FTIR) assessment, ninhydrin assay, and swellability. The effects of PAMAM incorporation on mechanical and degradation properties of CEM were evaluated using a uniaxial mechanical test and collagenase degradation assay, respectively. Ninhydrin assay and FTIR assessment confirmed the presence of increasing free amine groups with increasing quantity of PAMAM in dendrimer-incorporated CEM (DENCEM) scaffolds. The amount of dendrimer used was found to be critical in controlling scaffold degradation, shrink temperature, and free amine content. Cell culture studies showed that fibroblasts seeded on DENCEM maintained their metabolic activity and ability to proliferate in vitro. In addition, fluorescence cell staining and scanning electron microscopy analysis of cell-seeded DENCEM showed preservation of normal fibroblast morphology and phenotype

Feminist Relational Theory

Accounts of human beings as essentially social have had a long history in philosophy as reflected in the Ancient Greeks; in African and Asian philosophy; in Modern European thinkers such as Mary Wollstonecraft, David Hume, Adam Smith, and Karl Marx; in continental philosophy; in pragmatism; in Indigenous thought, and in contemporary communitarian theories. It can be said, then, that the language of relational theory has taken a variety of forms. That relational theory is broad and captures various threads in the history of philosophy is captured in the main title of this special issue, Relational Theory. That this special issue zeroes in on the distinctive features and contributions of feminist relational theory is captured in the subtitle, Feminist Approaches, Implications, and Applications, and explained in this introduction. This special issue of Journal of Global Ethics is devoted to exploring, extending, applying, and deepening relational insights emerging from today’s feminist relational theory

Teaching Race and Racial Justice: Developing Students’ Cognitive and Affective Understanding

Effectively addressing both cognitive and affective dimensions of learning is one of the greatest obstacles to teaching race and racial justice in higher education. In this article, we first explore the need to integrate attention to cognitive and affective development, along with evidence-based strategies for doing so. We then provide a case study of an undergraduate sociology course on environmental justice in which the instructor intentionally adopted holistic pedagogical principles of teaching race. Analyzing student responses from a pre- and post- course survey, course assignments, and instructor observations of student participation, we find that both white students and students of color experienced significant growth in their cognitive and affective understanding of the complexities of race and work toward racial justice. However, results also show how challenging it can be to create the conditions for productive multiracial dialogues that produce extensive affective development, particularly interpersonal skills of racial reconciliation. Reflecting on the limitations of the case, we conclude that more holistic teaching approaches are necessary to develop both students’ cognitive and affective abilities to navigate race and work against racism, and we make suggestions for faculty development and administrative support

Teaching Race, Racism, and Racial Justice: Pedagogical Principles and Classroom Strategies for Course Instructors

Teaching on topics of race and racism presents unique challenges to leaders in the university classroom setting. Despite an increasing number of instructors bringing a critical analysis of racial in/justice to their curriculum, many report challenges in teaching this content effectively. In this article, we address these challenges. We define common challenges in teaching racial content and articulate four principles for course planning around topics of race, racism, and racial justice. Then, drawing on a systematic review of scholarship examining issues of difference within a diverse range of disciplinary settings, we introduce a set of five pedagogical strategies, and supporting classroom practices, that will help instructors effectively manage everyday classroom interactions. This article contributes to the vast literature on teaching race and anti-racist education by synthesizing guiding pedagogical principles for course planning and classroom management that are applicable in a wide array of disciplinary contexts and providing concrete strategies that committed instructors, at varying levels of experience, can implement in their courses

A Novel High-Throughput, High-Content Three-Dimensional Assay for Determination of Tumor Invasion and Dormancy

Metastasis accounts for most cancer deaths, while dormancy of tumor cells leads to unexpected cancer recurrence. These two aspects of cancer remain relatively untreatable in part because current two-dimensional (2D) methods of high-throughput drug screening cannot quantify outcomes related to these phenotypes. Three-dimensional (3D) in-vitro tumor models are a promising alternative because they better recreate the tumor microenvironment and relevant phenotypes. However, outcome measures for high-throughput screening of these systems are often limited to single measures such as metabolic activity using assays that are not standardized or optimized for 3D models. To address this gap, the objective of this work to develop an image-based assay to measure tumor cell health, proliferation, invasion, and dormancy for high-throughput drug screening. Drug dosing experiments were performed using a novel 3D pancreatic tumor metastasis model, followed by application of various dye combinations to assess viability, proliferation, metabolic activity, and invasion. We successfully demonstrated that high throughput imaging and analysis can be performed to quantify proliferation, metabolic activity, and invasion in a single multi-output assay. Proof-of-concept experiments also revealed that while gemcitabine does effectively inhibit cancer cell proliferation it does not kill all cells and may contribute to tumor dormancy. Overall, this work using a novel 3D tumor metastasis model coupled with a multi-output assay serves as a first step toward a drug screening platform that will enable researchers to better correlate in-vitro model results with clinical outcomes related to metastasis and dormancy

Modeling the Effect of Land Use Change on Hydrology of a Forested Watershed in Coastal South Carolina

2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Regio

Modeling the Effect of Land Use Change on Hydrology of a Forested Watershed in Coastal South Carolina

2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Regio

In vitro Anticancer Screening of 24 Locally Used Nigerian Medicinal Plants

Background: Plants that are used as traditional medicine represent a relevant pool for selecting plant candidates that may have anticancer properties. In this study, the ethnomedicinal approach was used to select several medicinal plants native to Nigeria, on the basis of their local or traditional uses. The collected plants were then evaluated for cytoxicity. Methods: The antitumor activity of methanolic extracts obtained from 24 of the selected plants, were evaluated in vitro on five human cancer cell lines. Results: Results obtained from the plants screened indicate that 18 plant extracts of folk medicine exhibited promising cytotoxic activity against human carcinoma cell lines. Erythrophleum suaveolens (Guill. & Perr.) Brenan was found to demonstrate potent anti-cancer activity in this study exhibiting IC50 = 0.2-1.3 $\mu$g/ml. Conclusions: Based on the significantly potent activity of some plants extracts reported here, further studies aimed at mechanism elucidation and bio-guided isolation of active anticancer compounds is currently underway.Chemistry and Chemical Biolog

Robust Sex Determination in the Caenorhabditis nigoni Germ Line

Sexual characteristics and reproductive systems are dynamic traits in many taxa, but the developmental modifications that allow change and innovation are largely unknown. A leading model for this process is the evolution of self-fertile hermaphrodites from male/female ancestors. However, these studies require direct analysis of sex-determination in male/female species, as well as in the hermaphroditic species that are related to them. In Caenorhabditis nematodes this has only become possible recently, with the discovery of new species. Here, we use gene editing to characterize major sex-determination genes in C. nigoni, a sister to the widely studied hermaphroditic species C. briggsae. These two species are close enough to mate and form partially fertile hybrids. First, we find that tra-1 functions as the master regulator of sex in C. nigoni, in both the soma and the germ line. Surprisingly, these mutants make only sperm, in contrast to tra-1 mutants in related hermaphroditic species. Moreover, the XX mutants display a unique defect in somatic gonad development that is not seen elsewhere in the genus. Second, the fem-3 gene acts upstream of tra-1 in C. nigoni, and the mutants are females, unlike in the sister species C. briggsae, where they develop as hermaphrodites. This result points to a divergence in the role of fem-3 in the germ line of these species. Third, tra-2 encodes a transmembrane receptor that acts upstream of fem-3 in C. nigoni. Outside of the germ line, tra-2 mutations in all species cause a similar pattern of partial masculinization. However, heterozygosity for tra-2 does not alter germ cell fates in C. nigoni, as it can in sensitized backgrounds of two hermaphroditic species of Caenorhabditis. Finally, the epistatic relationships point to a simple, linear germline pathway in which tra-2 regulates fem-3 which regulates tra-1, unlike the more complex relationships seen in hermaphrodite germ cell development. Taking these results together, the regulation of sex determination is more robust and streamlined in the male/female species C. nigoni than in related species that make self-fertile hermaphrodites, a conclusion supported by studies of interspecies hybrids using sex-determination mutations. Thus, we infer that the origin of self-fertility not only required mutations that activated the spermatogenesis program in XX germ lines, but prior to these there must have been mutations that decanalized the sex-determination process, allowing for subsequent changes to germ cell fates

Deletion of the eIFiso4G subunit of the Arabidopsis eIFiso4F translation initiation complex impairs health and viability

Arabidopsis thaliana knockout lines for the plant-specific eukaryotic translation initiation factors eIFiso4G1 (i4g1) and eIFiso4G2 (i4g2) genes have been obtained. To address the potential for functional redundancy of these genes, homozygous double mutant lines were generated by crossing individual knockout lines. Both single and double mutant plants were analyzed for changes in gross morphology, development, and responses to selected environmental stressors. Single gene knockouts appear to have minimal effect on morphology, germination rate, growth rate, flowering time, or fertility. However, double mutant i4g1/i4g2 knockout plants show reduced germination rates, slow growth rates, moderate chlorosis, impaired fertility and reduced long term seed viability. Double mutant plants also exhibit altered responses to dehydration, salinity, and heat stress. The i4g2 and i4g1/i4g2 double mutant has reduced amounts of chlorophyll a and b suggesting a role in the expression of chloroplast proteins. General protein synthesis did not appear to be affected as the levels of gross protein expression did not appear to change in the mutants. The lack of a phenotype for either of the single mutants suggests there is considerable functional overlap. However, the strong phenotypes observed for the double mutant indicates that the individual gene products may have specialized roles in the expression of proteins involved in plant growth and development