Study of the H-Ras-Rb Axis in Oncogene Induced Senescence

Denman Undergraduate Research Forum - 3rd Place Biological SciencesDysregulation of the oncogene H-Ras pathway is widely found in human superficial bladder cancer, while a Rb mutation co-exists with H-Ras mutation in the majority of invasive tumors. Preliminary data on mice with bladder-specific H-Ras activation and other previous reports on in vitro cell line assays have indicated that cellular senescence, a defense response that leads to irreversible cell cycle arrest and provides a barrier for tumor progression, can be induced by H-Ras activation. Extra mutations in tumor suppressors such as Rb could contribute to the breaking of senescence and tumor progression. Investigation into senescence began with immunohistochemistry on human bladder samples for phosphoERK and Rb, which found that phosphoERK was more commonly involved with the initiation of bladder cancer while Rb was more involved with its progression. With this data, a double transgenic mouse model was created with constitutively activated H-Ras and knocked out Rb, which was hypothesized to break the senescence response. The mice were bred and euthanized, with their bladders’ senescent activity bladders analyzed using beta-galactosidase and p15. Interestingly, we found a significant correlation between the H&E/beta-galactosidase of the double transgenic and H-Ras mice as compared to the normal mice, showing that an extra mutation was not sufficient to break senescence at the age of 6-months. Additionally, p15 was not found to not be an effective senescent indicator, with no patterns seen between the three genotypes of mice. Further analysis includes assessment of our 1-year-old mice and investigation towards other tumor suppressors that may drive tumor progressionPelotonia Undergraduate Fellowship ProgramOSUCCC Solid Tumor Biology ProgramNo embarg

Development of shape memory metal as the actuator of a fail safe mechanism

A small, compact, lightweight device was developed using shape memory alloy (SMA) in wire form to actuate a pin-puller that decouples the flanges of two shafts. When the SMA is heated it contracts producing a useful force and stroke. As it cools, it can be reset (elongated in this case) by applying a relatively small force. Resistive heating is accomplished by running a current through the SMA wire for a controlled length of time. The electronics to drive the device are not elaborate or complicated, consisting of a timed current source. The total available contraction is 3 percent of the length of the wire. This device, the engineering properties of the SMA, and the tests performed to verify the design concept are described

Chaidez v. United States - You Can\u27t Go Home Again

This article examines a 2013 Supreme Court decision, Chaidez v. United States, in which the Court declined to apply retroactively another recent decision, Padilla v. Kentucky. To many observers, Chaidez appears to be a discrete departure from previous Sixth Amendment right to counsel jurisprudence. On a personal level, noncitizens who pled guilty to a crime without being apprised of the plea’s removal risks are now unable to seek redress under Padilla and return to their homes in the United States. This article examines relevant Sixth Amendment and retroactivity jurisprudence and proposes an explanation for the Court’s apparent aboutface

Adolescent Midfacial Growth in Macaca nemestrina and Papio Cynocephalus

Samples of 40 Macaca nemestrina and 12 Papio cynocephalus were tested for positive midfacial growth spurts. Relative growth rates were calculated for the sella-prosthion (S-Pr) and first incisor-first molar (P-M1) dimensions and trunk height using 6 observations between 2 and 7 years of age. Paired t-tests between chronologically adjacent rates revealed significant increases for S-Pr of male M. nemestrina but not for other comparisons. Individual growth rate curves for all three dimensions were examined to detect growth spurts of variable onset. The majority of male and female macaques and of male baboons showed positive growth spurts in S-Pr when individual rates were compared. The majority of both sexes of both species had growth spurts for trunk height. Growth spurts for P-M1 were most frequently absent in females of both species. Peak growth rates and growth rate increases were uniformly greater for males than females. S-Pr rate increases were more frequently present in conjunction with trunk height spurts than with P-M\u27 growth accelerations. As with human samples, there exists a variable age of onset and duration of the midfacial growth spurt

The beginning public speaking course for engineers

There is no abstract available for this research paper.Thesis (M.A.

Educational administration today

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