PRONATE GLOBALLY BUT SUPINATE LOCALLY: EVIDENCE OF RADIO-ULNAR SUPINATION AT BALL RELEASE

The purpose of this study was to investigate the radio-ulnar longitudinal rotation during baseball pitching. We captured movements of nine skilled pitchers during pitching by using a system with 16 high-speed cameras (Vicon MX, 1000 Hz). Ten fastest trials which hit a target were averaged to obtain representative data for each participant. We found that the radio-ulnar joint supinated at around the moment of ball release (BRL), although the wrist continued rotating in the direction of pronation at around BRL in the global coordinate. The supination occurred due to the influence of the combination of elbow extension and shoulder internal rotation

STERNOCLAVICULAR JOINT MOVEMENT DURING BACKSWING IN BASEBALL PITCHING MAY BE A GOOD INDICATOR OF SHOULDER INJURY

The purpose of this study was to demonstrate the characteristics of joint movements performed by the pitchers who suffered from throwing shoulder injuries. Fourteen semiprofessional baseball pitchers participated in our longitudinal study. We captured their pitching using an optical motion capture system. We investigated their disease history once a year, for 5 years, in order to investigate the relationship between baseball-related throwing injuries and pitching mechanics. T w of the players suffered from shoulder pain and had to take a "no throw" rest for several weeks during the season. Both pitchers had a reduced range of motions for retraction at the sternoclavicular joint during backswing. However, they presented the same range of motions for shoulder horizontal abduction, as the other healthy pitchers

Redundant roles of EGFR ligands in the ERK activation waves during collective cell migration

Epidermal growth factor receptor (EGFR) plays a pivotal role in collective cell migration by mediating cell-to-cell propagation of extracellular signal-regulated kinase (ERK) activation. Here, we aimed to determine which EGFR ligands mediate the ERK activation waves. We found that epidermal growth factor (EGF)–deficient cells exhibited lower basal ERK activity than the cells deficient in heparin-binding EGF (HBEGF), transforming growth factor alpha (TGFα) or epiregulin (EREG), but all cell lines deficient in a single EGFR ligand retained the ERK activation waves. Surprisingly, ERK activation waves were markedly suppressed, albeit incompletely, only when all four EGFR ligands were knocked out. Re-expression of the EGFR ligands revealed that all but HBEGF could restore the ERK activation waves. Aiming at complete elimination of the ERK activation waves, we further attempted to knockout NRG1, a ligand for ErbB3 and ErbB4, and found that NRG1-deficiency induced growth arrest in the absence of all four EGFR ligand genes. Collectively, these results showed that EGFR ligands exhibit remarkable redundancy in the propagation of ERK activation waves during collective cell migration

Knockout of all ErbB-family genes delineates their roles in proliferation, survival, and migration

The ErbB-family receptors play pivotal roles in the proliferation, migration, and survival of epithelial cells. Because our knowledge on the ErbB-family receptors was obtained largely by the exogenous application of their ligands, it remains unknown to which extent each of the ErbB contributes to these outputs. We here knocked out each ErbB gene, various combinations of ErbB genes, or all in Madin-Darby canine kidney cells to delineate the contribution of each gene. ERK activation waves during collective cell migration were mediated primarily by ErbB1 and secondarily by the ErbB2/ErbB3 heterodimer. Either ErbB1 or the ErbB2/ErbB3 complex was sufficient for the G1/S progression. The saturation cell density was markedly reduced in cells deficient in all ErbB-proteins, but not cells retaining only ErbB2, which cannot bind to ligands. Thus, the ligand-independent ErbB2 activity is sufficient for preventing apoptosis at high cell density. In short, systematic knockout of ErbB-family genes delineated the roles of each ErbB receptor

Experimental study on vertical void for improving natural ventilation in midrise double-loaded apartments

Affordable apartments in tropical developing countries generally have double-loaded corridors to maximise the total floor areas. Building designs with double-loaded corridors often suffer from poor environmental conditions. Passive design using a vertical void can help improve the natural ventilation in the such building design. This study investigates the effectiveness of vertical voids in enhancing the wind speed in the building. An experimental building with a vertical void, open pilotis, penthouse at rooftop and wind fin on the ground floor to help direct air to the void was constructed in Tegal, Indonesia. Five cases were considered by controlling the window openings, louver openings on the roof and change in fin size at pilotis. Wind speed and direction were recorded at one-second intervals. High wind speed was experienced in the pilotis and void when the wind direction is from the north and the wind speed in the void improved due to the wind fin being placed on the south corridor of the building. The results show the average wind speed in the void is twice as high as compared to the corridors. The building design performed best with high wind speeds in the void and corridores when all windows were kept open