The vitamin D analog, 1alpha-fluoro-16-ene-20-epi-23-ene-26,27-bishomo-25-hydroxyvitamin D(3) (Ro-26-9228) is tissue selective, with a gene regulation preference for bone over duodenum in vivo. In the human osteoblast-like cells, hFOB, the vitamin D receptor (VDR)-mediated transcriptional potencies of Ro-26-9228 and 1,25-dihydroxyvitamin D(3) (1,25D(3)) were similar, but in the intestinal cells, Caco-2, transcriptional potency of Ro-26-9228 was 10-50 times lower. We hypothesized that transcriptional activation of the VDR by Ro-26-9228 in the two cell types is regulated differently, and compared VDR extracted from hFOB or Caco-2 cells for their abilities to interact with a p160 coactivator [glucocorticoid receptor-interacting protein (GRIP)] and with retinoid X receptor (RXR) by pull-down assays. 1,25D(3) had similar potencies to induce interactions of VDR from the two cell types with these partners of transcription. In contrast, Ro-26-9228 induced interaction of osteoblastic VDR with RXR and GRIP but did not induce these interactions with VDR from Caco-2 cells. Further studies revealed that in hFOB cells the unoccupied VDR was cytoplasmic and proteasome sensitive, and that ligand treatment caused a rapid accumulation of the VDR in the chromatin. Both cytoplasmic and chromatin-associated ligand-bound VDR from hFOB cells had the abilities to interact with GRIP. In contrast, in Caco-2 cells, unoccupied VDR was localized in both the cytoplasm (70%) and the chromatin (30%). In Caco-2 cells, the cytoplasmic VDR was proteasome resistant, and neither 1,25D(3) nor Ro-26-9228 induced its binding to GRIP. Only a small fraction of the chromatin-associated VDR was proteasome sensitive, and this fraction was distinguishable by a faster electrophoretic mobility. 1,25D(3) induced an accumulation of the proteasome-sensitive VDR in the chromatin of Caco-2 cells and binding to GRIP. Ro-26-9228 failed to induce accumulation of the proteasome-sensitive VDR in the chromatin or binding to GRIP, but a coincubation of Caco-2 cells with the analog and a proteasome inhibitor restored these abilities. These results suggest that Ro-26-9228 has poor ability to promote the accumulation of a proteasome-sensitive, transcriptionally active VDR isoform in Caco-2 cells, whereas it does not have this limitation in hFOB cells.

Background: Clinical methods for assessing quality of movement and functional tests are important to clinicians. Typical deviations from normal kinematics during the clinical test of Forward Step Down Test (FSDT) are pelvic tilt and hip adduction which are associated with the risk of knee pain.Objectives: (1) to examine the correlation between clinical assessment of the FSDT and joint angle measurements of pelvis, hip, knee and ankle joints in males and females; (2) to examine the differences in joint angles between individuals rated as good, fair or poor in a FSDT performance test.Methods: Ninety-two healthy individuals performing FSDT were video-taped with two-dimensional digital video cameras. The clinical assessment of the FSDT was rated by two experienced physical therapists as good, fair, or poor based on a Crossley et al. (2011) validated scale. Measurements of pelvic drop, hip adduction and knee valgus were taken using Image J software.Results: Out of 177 lower limbs, 74 (37 in each limb) were clinically rated as “good/fair” (41.80%) while 103 (52 in the dominant leg and 51 in the non-dominant leg) were rated as “poor” (58.19%). No significant differences were observed between dominant and non-dominant legs or between males and females in clinical rating of the FSDT. Pelvic drop angle was significantly higher and hip adduction angle was significantly lower for “poor” clinical rating compared to “good/fair” in both dominant and non-dominant legs (p < 0.001) in males and females. Females demonstrated higher pelvic drop, lower hip adduction and higher knee valgus angles compared with males (p < 0.05).Conclusions: This study showed that the clinical rating of FSDT is correlated with joint angle measurements suggesting that this assessment can be utilized in clinical practice. Individuals with poor quality performance of FSDT showed higher pelvic drop and hip adduction movement. Further studies examining different populations with diverse disorders or pathologies are essential.

Background: Isokinetic studies of wrist flexion and extension (WFE) have been conducted mostly in the concentric mode. However, the eccentric counterpart is of specific importance in strength profiling while both modes are differently expressed in women and men. Objective: to characterize the isokinetic concentric and eccentric isokinetic strength of the dominant side WFE, in a group of healthy young women and men and explore their respective internal and external relationships. Methods: 20 women and 20 men were tested while standing with forearm in neutral position, using a RoM of 60° and a speed of 120°/s for both contraction modes. Isometric grip strength was measured using a standard apparatus. Results: Men were significantly stronger than women, the flexors significantly stronger than the extensors and the eccentric strength significantly higher than its concentric counterpart. A correlation matrix based on the concentric and eccentric peak moments of the WFE revealed that men had significantly higher correlation coefficients compared to women. Conclusions: While supporting the efficiency of the test position, the significant sex-related difference in the strength correlations pattern may reflect an acquired-adaptive trait but this assumption requires further research.

The training of near-peer (NP) teachers and junior faculty instructors received major attention as a possible solution for the shortage of experienced anatomy instructors in faculties of medicine and health professions. Several studies described the training of NP teachers and junior instructors (≤ 2 years of teaching experience) using various methods. However, few publications include On the Job Training (OJT), which enables reflection and performance evaluation and encourages professionals to cope with their blind spots. Previous publications describing OJT did not include formal observation of the NP teacher or junior instructor. Therefore, this study aimed to present a novel approach to OJT inclusion during prosection laboratories based on the Lewinian experiential model. Eight physical therapy (PT) graduates were recruited as junior anatomy instructors into the prosection laboratories. All participated in a unique training program during two consecutive academic years (2017, 2018) and received OJT during the teaching sessions. Two questionnaires were filled out to evaluate the educational impact of the training program. Eighty-three first-year PT students participated in prosection laboratories in anatomy taught by junior instructors, and filled out a questionnaire evaluating the performance of both junior and senior instructors. In addition, we compared the final grades in anatomy obtained by students taught by senior instructors to the grades of those taught by junior instructors. Each junior anatomy instructor participated in four OJT sessions. Based on self-reported measures, all professional and didactic aspects of the training program received a median score of 4.5 or higher on a five-point Likert scale. Students obtained similar grades in anatomy when taught by junior instructors compared with senior ones, and were similarly satisfied from the teaching performance of both senior and junior anatomy instructors. OJT is applicable in a small-sized PT program facing a shortage of anatomy instructors. Including junior anatomy instructors in prosection laboratories for PT students is a viable solution to the shortage of experienced anatomy instructors. Further study, involving a larger cohort with a longer follow up will strengthen the preliminary results presented here.

Performance fatigability is characterized by a decline in the capacity to maintain force or power during sustained or repeated activity. This exploratory study quantified knee-extensor mechanical performance and rectus femoris surface electromyographic (sEMG) changes during repeated maximal isokinetic knee extensions and explored sex-related differences. Twenty-nine healthy adults (20 men, 9 women; 20–31 years) performed 30 maximal concentric knee extensions at 180°·s⁻¹. Mechanical outcomes were analyzed in all 29 participants, whereas rectus femoris sEMG outcomes were analyzed in 23 participants. Peak torque (PT) decreased by 32.75 ± 11.66% (adjusted p = 6.08 × 10⁻¹¹), work per repetition by 33.35 ± 11.97% (adjusted p = 2.12 × 10⁻¹¹), and mean frequency (MNF) by 23.44 ± 8.33% (adjusted p = 6.08 × 10⁻¹¹). RMS increased significantly from Start to End (adjusted p = 0.000639), with a mean FI-RMS of −17.12 ± 23.11%. FI-PT and FI-work were very strongly associated (ρ = 0.938, adjusted p = 3.71 × 10⁻¹³), whereas no association involving rectus femoris MNF or RMS remained statistically significant after Holm–Bonferroni correction. No statistically significant sex-related differences were detected. Repeated maximal knee extensions reduced mechanical performance and rectus femoris MNF while increasing RMS. FI summarizes Start-to-End change across the measured outcomes; its reliability and validity require further investigation.