A novel activation mechanism of cellular Factor XIII in zebrafish retina after optic nerve injury.

Cellular Factor XIII (cFXIII) mRNA is rapidly upregulated in the fish retina after optic nerve injury (ONI). Here, we investigated the molecular mechanism of cFXIII gene activation using genetic information from the A-subunit of cFXIII (cFXIII-A). Real-time PCR that amplified the active site (exons 7-8) of cFXIII-A showed increased cFXIII-A mRNA in the retina after ONI, whereas the PCR that amplified the activation peptide (exons 1-2) showed no change. RT-PCR analysis that amplified exons 1-8 showed two bands, a faint long band in the control retina and a dense short band in the injured retina. Therefore, we conclude that activated cFXIII-A mRNA after ONI is shorter than that of the control retina. Western blot analysis also confirmed an active form of 65 kDa cFXIII-A protein in the injured retina compared to the control 84 kDa protein. 5'-RACE analysis using injured retina revealed that the short cFXIII-A mRNA lacked exons 1, 2 and part of exon 3. Exon 3 has two sites of heat shock factor 1 (HSF-1) binding consensus sequence. Intraocular injection of HSF inhibitor suppressed the expression of cFXIII-A mRNA in the retina 1 day after ONI to 40% of levels normally seen after ONI. Chromatin immunoprecipitation provides direct evidence of enrichment of cFXIII-A genomic DNA bound with HSF-1. The present data indicate that rapid HSF-1 binding to the cFXIII-A gene results in cleavage of activation peptide and an active form of short cFXIII-A mRNA and protein in the zebrafish retina after ONI without thrombin.

Hand Selection in Dribbling Phases: An Analysis of Non-Dominant Hand Usage and Dribble Change in Basketball.

This study investigates the influence of different dribbling phases on hand selection among basketball players across various categories. A total of 33 guard players, including 11 from high school, college, and NBA teams each, were observed. Video data analysis was utilized to determine the frequency of players using their dominant hands (DHs) and non-dominant hands (NDHs) during in-game dribbling phases. The dribbling phases were classified into three categories: First (the initiation of the dribble), Middle (during the dribble but not in First and Last), and Last (the completion of the dribble). Percentage, means, and standard deviations were computed for each category within the First, Middle, and Last measurements. A two-factor analysis of variance (ANOVA) was conducted, considering player category and dribbling phase as factors. The ANOVA revealed significant main effects of player category (p < 0.01) and dribbling phase (p < 0.01). Post hoc multiple comparisons using Holm's method indicated that, in the First phase, players exhibited a 6.5% higher preference for using their NDHs (43.4 ± 11.9%) compared to the Middle phase (36.9 ± 13.9%) (p < 0.05). Similarly, in the Last phase, players displayed a 5.3% greater inclination towards using their NDHs (42.2 ± 11.7%) compared to the Middle phase (p < 0.05). These findings provide quantitative evidence that the specific dribbling phase influences hand selection during gameplay. The implications of these results are significant for basketball coaches, as they can design targeted training programs and drills that simulate game scenarios and encourage NDH usage. By understanding the factors influencing hand choice, players can enhance their versatility and adaptability on the court. Furthermore, these findings contribute to player performance, skill development, and strategic decision making in dribbling phases.