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Previous research has established that SAT scores and high school grade point average (HSGPA) differ in their predictive power and in the size of mean differences across racial/ethnic groups. However, the SAT is scaled nationally across all test takers while HSGPA is scaled locally within a school. In this study, the researchers propose that this difference in how SAT scores and HSGPA are scaled partially explains differences in validity and subgroup differences. Using a large data set consisting of 170,390 students each of whom matriculated at one of 114 separate colleges, the researchers find that awarding SAT scores by ranking SAT within a high school generally results in substantial reduction in the size of subgroup mean differences for this predictor. However, validity for predicting first-year GPA is also reduced by a small amount. Conversely, placing HSGPA onto a nationally normed metric through the use of multiple regression procedures results in a moderate increase in the size of subgroup mean differences, while also producing a small increase in validity. Taken together, these findings suggest that differences in predictor scaling can partially explain differences in the size of subgroup mean differences between HSGPA and SAT scores and have implications for predictive power.

Aims: The genetic aspect of degenerative joint disease (DJD) of the temporomandibular joint is poorly understood. The prevalence of the estrogen receptor alpha (ER-alpha) gene polymorphism in patients with and without DJD using xbal and pvull restriction fragment length polymorphisms (RFLPs) was studied.Methodology: DNA samples from 42 DJD⁺ and 36 DJD⁻ subjects were amplified. A 346-base pair long ER-alpha gene fragment containing the two sites of polymorphism in intron 1 was analyzed for xbal and pvull RFLP. Statistical analysis was carried out using Fisher's exact test and two-group t-test.Results: Five different ER-alpha genotypes were found in both groups. These were PXPX, pxpx, pxPX, PxPX, and pxPx.Discussion: There was a higher number of pxpx and pxPX genotypes in the DJD⁺ samples compared to the DJD⁻ group, which suggests the presence of polymorphism possibly modulates the ER-alpha activity in bone and contributes to the degenerative process in the joint. [ABSTRACT FROM AUTHOR]

To investigate the role of bone morphogenetic protein (BMP) signaling in osteoclastogenesis in vivo, we eliminated BMPRII in osteoclasts by creating a BMPRIIfl/fl;lysM-Cre mouse strain. Conditional knock-out (cKO) mice are osteopetrotic when compared with WT controls due to a decrease in osteoclast activity. Bone marrow macrophages (BMMs) isolated from cKOmice are severely inhibited in their capacity to differentiate into mature osteoclasts in the presence of M-CSF and receptor activator of NF-κB (RANK) ligand. We also show that BMP noncanonical (MAPK) and canonical (SMAD) pathways are utilized at different stages of osteoclast differentiation. BMP2 induces p38 phosphorylation in pre-fusion osteoclasts and increases SMAD phosphorylation around osteoclast precursor fusion. Phosphorylation of MAPKs was decreased in differentiated BMMs from cKO animals. Treating BMMs with the SMAD inhibitor dorsomorphin confirms the requirement for the canonical pathway around the time of fusion. These results demonstrate the requirement for BMP signaling in osteoclasts for proper bone homeostasis and also explore the complex signaling mechanisms employed by BMP signaling during osteoclast differentiation. [ABSTRACT FROM AUTHOR]

Aims: The genetic aspect of degenerative joint disease (DJD) of the temporomandibular joint is poorly understood. The prevalence of the estrogen receptor alpha (ER-alpha) gene polymorphism in patients with and without DJD using xbal and pvull restriction fragment length polymorphisms (RFLPs) was studied., Methodology: DNA samples from 42 DJD⁺ and 36 DJD⁻ subjects were amplified. A 346-base pair long ER-alpha gene fragment containing the two sites of polymorphism in intron 1 was analyzed for xbal and pvull RFLP. Statistical analysis was carried out using Fisher's exact test and two-group t-test., Results: Five different ER-alpha genotypes were found in both groups. These were PXPX, pxpx, pxPX, PxPX, and pxPx., Discussion: There was a higher number of pxpx and pxPX genotypes in the DJD⁺ samples compared to the DJD⁻ group, which suggests the presence of polymorphism possibly modulates the ER-alpha activity in bone and contributes to the degenerative process in the joint.