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Biology subjects

Tani, Y.

Publications and source records attributed to Tani, Y..

3 recordsLinked to original sources

Biomechanical characteristics of scapula and glenohumeral movements during pitching motion in injury-prone college baseball pitchers

Coordination of glenohumeral and scapular movements plays an important role in the injury prevention of baseball pitchers. However, there is no objective data establishing the direct relationship between pitching injuries and associated glenohumeral and scapular movements. Therefore, the objectives of the present study were to demonstrate biomechanical differences in scapular and glenohumeral movements during pitching between injury-prone pitchers and healthy college baseball pitchers. Thirty collegiate baseball pitchers were classified into two groups according to their injury status: injury-prone group (N=15, 20.7{+/-}1.4 years, 180.1{+/-}6.5 cm, 78.9{+/-}5.4 kg) and control group (N=15, 20.9{+/-}1.1 years, 177.1{+/-}6.6 cm, 72.3{+/-}6.7 kg). We obtained the pitching motion data using the three-dimensional motion analysis technique with four high-speed cameras. The horizontal abduction angles of the glenohumeral joint during cocking and acceleration phases were significantly greater in injury-prone pitchers [19.0{degrees} (95% CI: 14.4-23.6) at foot contact, -4.0{degrees} (95% CI: -7.7 to -0.2) at maximum external rotation (MER), and -0.3{degrees} (95% CI: -4.8 to -4.2) at ball release] than in healthy controls [11.7 {degrees}(95%CI:7.1 to 16.3) at foot contact, -10.0{degrees}(95%CI: -13.7 to -6.3) at MER, and -6.9{degrees}(95%CI: -11.4 to -2.4)](p<0.01). In addition, the external rotation angle (ER) of the scapula at MER was significantly greater in the injury-prone group [-0.1{degrees} (95% CI: -5.0 to 4.8)] than in the control group [-12.3{degrees} (95% CI: -17.2 to -7.4)] (p<0.01), but there was no difference in the scapular ER during foot contact between the two groups. These results suggests that injury-prone pitchers have less internal rotation of the scapula and more horizontal abduction of the glenohumeral joint during cocking and acceleration phases. Therefore, sports medicine practitioners may need to pay more attention to coordination of scapular and glenohumeral movements during the cocking and acceleration phases of pitching for prevention of shoulder injuries.

physiology↗

Development of novel potent ligands for GPR85, an orphan G protein-coupled receptor expressed in the brain

GPR85 is a member of the G protein-coupled receptor and is a super-conserved receptor expressed in the brain sub-family (SREB) with GPR27 and GPR173. These three receptors are "orphan receptors"; however, their endogenous ligands have not been identified. SREB has garnered the interest of many scientists because it is expressed in the central nervous system and is evolutionarily conserved. In particular, brain mass is reported to be increased and learning and memory are improved in GPR85 knockout mice (Matsumoto et al., 2008). In this study, we characterized newly synthesized compounds using a GPR85-Gs fusion protein and the [35S]GTP{gamma}S binding assay and identified novel GPR85 inverse-agonists with IC50 values of approximately 1 {micro}M. To analyze the neurochemical character of the compounds and investigate the physiological significance of GPR85, we used cerebellar Purkinje cells expressing GPR85 and an electrophysiological technique. Based on the results, the inverse-agonist compound for GPR85 modulated potassium channel opening. Together with the results of previous gene analysis of GPR85, we expect that the development of the GPR85 ligand will provide new insights into a few types of neurological disorders.

pharmacology and toxicology↗

Erythrocyte CD55 mediates the internalization of Plasmodium falciparum parasites

Invasion of human erythrocytes by the malaria parasite Plasmodium falciparum is a multi-step process. Previously, a forward genetic screen for P. falciparum host factors identified erythrocyte CD55 as essential for invasion, but its specific role and how it interfaces with the other factors that mediate this complex process are unknown. Using CRISPR-Cas9 editing, antibody-based inhibition, and live cell imaging, here we show that CD55 is specifically required for parasite internalization. Pre-invasion kinetics, erythrocyte deformability, and echinocytosis were not influenced by CD55, but entry was inhibited when CD55 was blocked or absent. Visualization of parasites attached to CD55-null erythrocytes point to a role for CD55 in progression of the moving junction. Our findings demonstrate that CD55 acts after discharge of the parasites rhoptry organelles, and plays a unique role relative to all other invasion receptors. As the requirement for CD55 is strain-transcendent, these results suggest that CD55 or its interacting partners may hold potential as therapeutic targets for malaria.

microbiology↗