Exploiting Nucleotide Composition to Engineer Promoters

The choice of promoter is a critical step in optimizing the efficiency and stability of recombinant protein production in mammalian cell lines. Artificial promoters that provide stable expression across cell lines and can be designed to the desired strength constitute an alternative to the use of viral promoters. Here, we show how the nucleotide characteristics of highly active human promoters can be modelled via the genome-wide frequency distribution of short motifs: by overlapping motifs that occur infrequently in the genome, we constructed contiguous sequence that is rich in GC and CpGs, both features of known promoters, but lacking homology to real promoters. We show that snippets from this sequence, at 100 base pairs or longer, drive gene expression in vitro in a number of mammalian cells, and are thus candidates for use in protein production. We further show that expression is driven by the general transcription factors TFIIB and TFIID, both being ubiquitously present across cell types, which results in less tissue- and species-specific regulation compared to the viral promoter SV40. We lastly found that the strength of a promoter can be tuned up and down by modulating the counts of GC and CpGs in localized regions. These results constitute a “proof-of-concept” for custom-designing promoters that are suitable for biotechnological and medical applications

Mastery Motivational Climate: Influencing Vocational Students\u27 Enjoyment of Physical Activity

Background/Purpose: Physical activity in children declines more than a third from 9-15 years of age (Nader et al., 2008). Consequently, drug abuse and smoking have taken a backseat to obesity the top health concern for parents in the United States because of its link to disease (American Heart Association, 2010). Children of particular concern are vocational high school students, because their career lifestyle may be linked to poor health habits, such as low physical activity (AHA, 2010; Pampel, et al., 2010). Exposing these students to a mastery motivational climate classroom (e.g., Duda, 1996; Grasten, et al., 2012, Ntoumanis & Biddle, 1999) may increase physical activity enjoyment, thus physical activity during adolescence and perhaps lifelong physical activity habits. The purpose of this study was to investigate the effects of a mastery motivational physical education classroom climate on vocational students\u27 physical activity enjoyment. Method: Eight-four (males = 53, females = 31) first year students who attended a New England vocational school were randomly selected as participants. Institutional review board approval was obtained from Bridgewater State University prior to conducting research. A hybrid of the Sport Education Model and Teaching Games for Understanding Model was used to create a mastery motivational climate. Pre and post measures of the participants\u27 perceptions of motivational climate and physical activity enjoyment were assessed using the Perceived Motivational in Sport Questionnaire (Newton, Duda, & Yin, 2000) and the five question Physical Activity Enjoyment Scale (Raedeke, T.D. & Amorose, A.J., 2013). A series of paired samples t-test with appropriate Bonferroni corrections determined significant post-intervention changes. Analysis/Results: Findings suggested that students perceived a significantly greater mastery motivational climate (post = 3.72+1.03; pre = 3.44+1.08 {p = .032} and a significantly higher level of physical activity enjoyment (post = 4.98+1.68; pre = 4.28+1.98 {p = \u3c .001} compared to the pre-tests. Females (4.25+0.94) perceived a significantly greater {p = .008} mastery motivational climate than males (3.69+1.05); both had significantly higher {female p = .008; male p = .001} physical activity enjoyment levels (female 4.99+1.67; male 5.01+1.67). Conclusions: Mastery motivational climate created through the hybrid SEM/TGFU Models effectively increased vocational students\u27 physical activity enjoyment levels, especially for female students. Future vocational student health may benefit from exposure to a mastery motivational climate in physical education as it could influence the development of lifelong physical activity habits

KINETIC ANALYSIS OF LANDING A GRAND JETÉ BETWEEN BAREFOOT AND POINTE SHOE FOOTWEAR FOR DOMINANT AND NON-DOMINANT LEGS

The purpose of this study was to examine the vertical ground reaction force in the skill of a Grand Jeté between barefoot and pointe shoes for both dominant and non-dominant legs. Seven female college dancers participated in the the study, and the results showed that there were no statistically significant differences between the landing legs or footwear conditions. However, there was an observable difference between the landing forces of the dominant and non-dominant legs, indicating that the dancers may be able to dissipate landing forces more effectively when landing on their dominant leg. This study provides a preliminary understanding on the effects of footwear between dominant and non-dominant legs. Future studies are warranted to evaluate the kinematics of lower body extremity to acquire a comprehensive understanding on the skill of Grand Jeté

The Effects of Load Mass on the Kinematics of Stiff-legged Deadlift

The purpose of this study was to investigate the effects of load mass on the kinematics of lower extremity joint movements during the stiff-legged deadlift (SLD) lift exercise. Five participants performed the SLD at 40%, 60%, and 80% of their estimated 1 repetition maximum. Measurements of the joint angle and angular velocity of the spine, hip, knee, and ankle were analyzed to understand the influence of various load masses in the SLD lifting technique. No statistical significant differences were found in the joint angles and angular velocities of the spine and lower extremity between different loads. Therefore, this study suggests that performing stiff-legged exercise up to 80% is safe to perform as long as the participants are experienced with this lifting technique

Investigation of the postcure reaction and surface energy of epoxy resins using time-of-flight secondary ion mass spectrometry and contact-angle measurements

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to investigate correlations between the molecular changes and postcuring reaction on the surface of a diglycidyl ether of bisphenol A and diglycidylether of bisphenol F based epoxy resin cured with two different amine-based hardeners. The aim of this work was to present a proof of concept that ToF-SIMS has the ability to provide information regarding the reaction steps, path, and mechanism for organic reactions in general and for epoxy resin curing and postcuring reactions in particular. Contact-angle measurements were taken for the cured and postcured epoxy resins to correlate changes in the surface energy with the molecular structure of the surface. Principal components analysis (PCA) of the ToFSIMS positive spectra explained the variance in the molecular information, which was related to the resin curing and postcuring reactions with different hardeners and to the surface energy values. The first principal component captured information related to the chemical phenomena of the curing reaction path, branching, and network density based on changes in the relative ion density of the aliphatic hydrocarbon and the C7H7O+ positive ions. The second principal component captured information related to the difference in the surface energy, which was correlated to the difference in the relative intensity of the CxHyNz+ ions of the samples. PCA of the negative spectra provided insight into the extent of consumption of the hardener molecules in the curing and postcuring reactions of both systems based on the relative ion intensity of the nitrogen-containing negative ions and showed molecular correlations with the sample surface energy.<br /

Humanised xenograft models of bone metastasis revisited: novel insights into species-specific mechanisms of cancer cell osteotropism

The determinants and key mechanisms of cancer cell osteotropism have not been identified, mainly due to the lack of reproducible animal models representing the biological, genetic and clinical features seen in humans. An ideal model should be capable of recapitulating as many steps of the metastatic cascade as possible, thus facilitating the development of prognostic markers and novel therapeutic strategies. Most animal models of bone metastasis still have to be derived experimentally as most syngeneic and transgeneic approaches do not provide a robust skeletal phenotype and do not recapitulate the biological processes seen in humans. The xenotransplantation of human cancer cells or tumour tissue into immunocompromised murine hosts provides the possibility to simulate early and late stages of the human disease. Human bone or tissue-engineered human bone constructs can be implanted into the animal to recapitulate more subtle, species-specific aspects of the mutual interaction between human cancer cells and the human bone microenvironment. Moreover, the replication of the entire "organ" bone makes it possible to analyse the interaction between cancer cells and the haematopoietic niche and to confer at least a partial human immunity to the murine host. This process of humanisation is facilitated by novel immunocompromised mouse strains that allow a high engraftment rate of human cells or tissue. These humanised xenograft models provide an important research tool to study human biological processes of bone metastasis