Regulation of vesicular nucleotide transporter (VNUT) in pancreatic β cells

2015 CFAES Undergraduate Research Forum Winner. First Place in "Animal Health"2015 Denman Undergraduate Research Forum Honorable Mention in "Health Professions- Laboratory/Cellular"Vesicular nucleotide transporter (VNUT) is a protein found in insulin granules that facilitates the uptake of ATP and release of ATP and insulin. Studies show that suppressed VNUT results in reduced insulin secretion. Currently, the regulation of VNUT expression in β cells is unknown. The objectives of this study were to determine the effect of high fat diet (HFD) on VNUT levels and test if free radicals generated from HFD are involved in HFD modulation of VNUT expression in β cells. A mouse insulin-producing cell line (MIN6) was used for this study. The control group received growth medium treatment, and the test group received growth medium containing fatty acids palmitate, oleate, and linoleate (1:2:1 ratio). The cells were lysed 48 hours after treatment, and protein was extracted for western blot analysis for VNUT. To further determine the effect of HFD in VNUT expression, adult male mice were fed either a control diet or HFD (n=3/group) for one week. We sacrificed the mice and isolated islets from the pancreas for protein content. Western blot was run in both models for VNUT expression, normalized against the housekeeping gene α-tubulin. Results validated a correlation between HFD and reduced VNUT levels compared to control group. Secondly, we introduced the drug BAM15, a mitochondrial uncoupler which has been shown to reduce reactive oxygen species production from mitochondia. Three trials were conducted with MIN6 cells in the following treatment groups: control, HFD, HFD + BAM15, and BAM15 only. After treatment for two days, western blot was run to determine VNUT expression. BAM15 showed a trend to restore VNUT levels in HFD-fed cells. Additional replications are necessary, as results with the drug were not statistically significant. Results of this study and the role of free radicals on modulating VNUT expression could have implications for managing diseases where insulin regulation is impaired.No embargoAcademic Major: Animal Science

Subjective Experience of Autonomy and Psychological Well-Being: A Cross-Cultural Study with Korean American and European American Young Adults

This study aimed to explore whether parenting beliefs and practices that might promote academic or professional achievements also undermine aspects of psychological well-being. Specifically, the study focused on the relationship between the experience of subjective autonomy and psychological well-being measured in terms of self-esteem, flourishing, and life satisfaction. The sample consisted of 86 second-generation Korean Americans (KAs) and 99 European Americans (EAs) ages 25-35. Perceived parental autonomy support (versus psychological control) and perceived parental modernity (versus traditionalism) were also examined for group differences and associations with psychological well-being. As a group, KAs perceived greater parental psychological control and parental traditionalism and lower levels of subjective autonomy. For both KAs and EAs, subjective autonomy was associated with psychological well-being. The connotations of a few parenting dimensions and psychological well-being indicators varied by ethnicity and acculturation; these variations are discussed as are overall implications for future research and practice. The implication of these findings is that the impediment to autonomy may stem from the presence of psychological control rather than the absence of autonomy support. Furthermore, contrary to some studies that regard the effects of parental psychological control as culturally syntonic, the findings of the present study indicate that perceived psychological control is negatively correlated with self-esteem among KAs as well as among EAs. For KAs, the experience of subjective autonomy is correlated with some indicators of psychological well-being, particularly those that pertain to the self as an individual, but less so for aspects of psychological well-being that bear on relationships or subjective standards, values, and aspirations. However, the findings of the present study indicate that the experience of autonomy is relevant to the psychological well-being of KAs, as it is to that of EAs

A stochastic and dynamical view of pluripotency in mouse embryonic stem cells

Pluripotent embryonic stem cells are of paramount importance for biomedical research thanks to their innate ability for self-renewal and differentiation into all major cell lines. The fateful decision to exit or remain in the pluripotent state is regulated by complex genetic regulatory network. Latest advances in transcriptomics have made it possible to infer basic topologies of pluripotency governing networks. The inferred network topologies, however, only encode boolean information while remaining silent about the roles of dynamics and molecular noise in gene expression. These features are widely considered essential for functional decision making. Herein we developed a framework for extending the boolean level networks into models accounting for individual genetic switches and promoter architecture which allows mechanistic interrogation of the roles of molecular noise, external signaling, and network topology. We demonstrate the pluripotent state of the network to be a broad attractor which is robust to variations of gene expression. Dynamics of exiting the pluripotent state, on the other hand, is significantly influenced by the molecular noise originating from genetic switching events which makes cells more responsive to extracellular signals. Lastly we show that steady state probability landscape can be significantly remodeled by global gene switching rates alone which can be taken as a proxy for how global epigenetic modifications exert control over stability of pluripotent states.Comment: 11 pages, 7 figure

Identification of Whole Mitochondrial Genomes from Venezuela and Implications on Regional Phylogenies in South America

Recent studies have expanded and refined the founding haplogroups of the Americas using whole mitochondrial (mtDNA) genome analysis. In addition to pan-American lineages, a number of studies have identified specific variants that show higher frequencies in restricted geographical areas. In order to further characterize Native American maternal lineages and specifically examine local patterns within South America, we analyzed twelve maternally unrelated Yekuana whole mtDNA genomes from one village (Sharamaña) that include the four major Native American haplogroups A2, B2, C1, and D1. Our study proposes a reconfiguration of one subhaplogroup A2 (A2aa) that is specific to South America and identifies other singleton branches across the four haplogroups. Furthermore, we show nucleotide diversity values that increase from north to south for haplogroups C1 and D1. The results from our work add to the growing mitogenomic data that highlight local phylogenies and support the rapid genetic differentiation of South American populations, which has been correlated with the linguistic diversity in the region by previous studies

A study of the relationship between a child's achievement and adjustment in grades one and three.

Thesis (Ed.M.)--Boston Universit

Does training matter? : construction quality for a new start transit system : the case of Tren Urbano

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2002.Includes bibliographical references (p. 99-104).As with many other large-scale infrastructure projects, the construction of a transit project is potentially vulnerable to quality failures, which can lead to completion delays and cost overruns. Especially with technologically advanced, new-start transit projects, a limitation or lack of skilled labor can exacerbate those risks. This thesis examines the case of Tren Urbano in San Juan, Puerto Rico, a rapid rail project currently being constructed in an area with limited on-island experience in the design, construction, operation or maintenance of such a technologically sophisticated transit system. The motivating question for this thesis is, does training matter for construction quality? The research findings of this thesis show that the multiple prime contractors operating under similar contractual arrangements and resource conditions in San Juan exhibit variations in the quality of construction. Research findings also reveal variations in the type of training programs established by the contractors. A limited conclusion is drawn that although training of inexperienced labor does not single-handedly insure high quality of construction, it nevertheless is important to the successful implementation of project design. Thus, this thesis argues that in order to maximize the quality of construction in a new transit system, the client-owners should create an appropriate strategy which carefully assesses and matches three factors: 1) procurement strategy, whether the conventional design-bid-build or innovative design-build arrangement, 2) contractor competence and experience, and 3) the existent local labor skill level or training capacity. A successful procurement strategy for the construction of future extensions to Tren Urbano should therefore consider: 1) choosing best-value bids over low bids, where the contractor has exhibited expertise and 2) training a broad range of skill sets, that includes explicit attention paid to the construction laborers and monitoring inspectors crucial for the quality of construction. Successful training should be tailored to pre-empt potential breakdowns of a particular procurement strategy. Furthermore, the training should also be an intentional, collaborative effort between the public education sector, the private construction sector, and an expanded labor union presence, and should fit within an overall industrial development policy of the government. An important theoretical contribution of this thesis is the expansion of the technology transfer discourse from a focus on an educated managerial class to include the ramping-up of skills for low-skilled, often uneducated, labor in order to expand the labor market for economic development while improving the profitability of the private sector ventures utilizing local labor.by Esther J. Lee.M.C.P

Steklov problem on differential forms

In this paper we study spectral properties of Dirichlet-to-Neumann map on differential forms obtained by a slight modification of the definition due to Belishev and Sharafutdinov. The resulting operator $\Lambda$ is shown to be self-adjoint on the subspace of coclosed forms and to have purely discrete spectrum there.We investigate properies of eigenvalues of $\Lambda$ and prove a Hersch-Payne-Schiffer type inequality relating products of those eigenvalues to eigenvalues of Hodge Laplacian on the boundary. Moreover, non-trivial eigenvalues of $\Lambda$ are always at least as large as eigenvalues of Dirichlet-to-Neumann map defined by Raulot and Savo. Finally, we remark that a particular case of $p$-forms on the boundary of $2p+2$-dimensional manifold shares a lot of important properties with the classical Steklov eigenvalue problem on surfaces.Comment: 18 page

Is a change in mode of travel to school associated with a change in overall physical activity levels in children? Longitudinal results from the SPEEDY study.

BACKGROUND: Children who use active modes of travel (walking or cycling) to school are more physically active than those who use passive (motorised) modes. However, less is known on whether a change in mode of travel to school is associated with a change in children's physical activity levels. The purpose of this analysis was to investigate the association between change in mode of travel to school and change in overall physical activity levels in children. METHODS: Data from 812 9-10 year old British children (59% girls) who participated in the SPEEDY study were analysed. During the summer terms of 2007 and 2008 participants completed a questionnaire and wore an accelerometer for at least three days. Two-level multiple linear regression models were used to explore the association between change in usual mode of travel to school and change in objectively measured time spent in MVPA. RESULTS: Compared to children whose reported mode of travel did not change, a change from a passive to an active mode of travel was associated with an increase in daily minutes spent in MVPA (boys: beta 11.59, 95% CI 0.94 to 22.24; girls: beta 11.92, 95% CI 5.00 to 18.84). This increase represented 12% of boys' and 13% of girls' total daily time spent in MVPA at follow-up. CONCLUSION: This analysis provides further evidence that promoting active travel to school may have a role in contributing to increasing physical activity levels in children.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Teaching health advocacy to medical students: a comparison study.

CONTEXT: Many encourage service learning and health advocacy training in medical student education, but related evaluation is limited. OBJECTIVES: To assess (1) impact of a required community health advocacy training for medical students on student attitudes, knowledge, and skills; (2) student characteristics associated with higher advocacy knowledge and skills; and (3) perspectives of community-based organizations (CBOs). DESIGN: Cross-sectional surveys. SETTING: University of Miami Miller School of Medicine (UMMSM) Regional Medical Campus and main campus. PARTICIPANTS: Medical students at both UMMSM campuses. INTERVENTION: Required community health advocacy training for first- and second-year students including classroom experiences and hands-on project in partnership with a CBO. MAIN OUTCOME MEASURES: Student characteristics, health advocacy-related attitudes, self-reported and objective knowledge, and skills. Scores were compared between campuses, with multivariable modeling adjusting for individual student characteristics. Community-based organization perspectives were assessed via separate surveys. RESULTS: Ninety-eight (77%) regional campus students (intervention group) and 139 (30%) main campus students (comparison group) completed surveys. Versus the comparison group, the intervention group reported greater: mean knowledge of community health needs: 34.6 versus 31.1 (range: 11-44, P \u3c .01), knowledge about CBOs: 3.0 versus 2.7 (range 1-4, P \u3c .01) and knowledge of community resources: 5.4 versus 2.3 (range, 0-11, P \u3c .01), and mean skill scores: 12.7 versus 10.5 (score range: 4-16, P \u3c .01), following the intervention. Using adjusted analysis across both groups, female gender was associated with higher attitudes score. High level of previous community involvement was associated with higher attitude and skill scores. Higher self-reported educational debt was associated with higher skill scores. Community-based organization perspectives included high satisfaction and a desire to influence the training of future physicians. CONCLUSIONS: Medical student advocacy training in partnership with community-based organizations could be beneficial in improving student advocacy knowledge and skills in addressing community health issues and in developing sustainable community partnerships

Synthetic biodegradable hydrogel delivery of demineralized bone matrix for bone augmentation in a rat model

There exists a strong clinical need for a more capable and robust method to achieve bone augmentation, and a system with fine-tuned delivery of demineralized bone matrix (DBM) has the potential to meet that need. As such, the objective of the present study was to investigate a synthetic biodegradable hydrogel for the delivery of DBM for bone augmentation in a rat model. Oligo(poly(ethylene glycol) fumarate) (OPF) constructs were designed and fabricated by varying the content of rat-derived DBM particles (either 1:3, 1:1 or 3:1 DBM:OPF weight ratio on a dry basis) and using two DBM particle size ranges (50–150 or 150–250 μm). The physical properties of the constructs and the bioactivity of the DBM were evaluated. Selected formulations (1:1 and 3:1 with 50–150 μm DBM) were evaluated in vivo compared to an empty control to investigate the effect of DBM dose and construct properties on bone augmentation. Overall, 3:1 constructs with higher DBM content achieved the greatest volume of bone augmentation, exceeding 1:1 constructs and empty implants by 3- and 5-fold, respectively. As such, we have established that a synthetic, biodegradable hydrogel can function as a carrier for DBM, and that the volume of bone augmentation achieved by the constructs correlates directly to the DBM dose