Purpose: It has previously been reported that repeated exposure to hypoxia increases spleen size and haemoglobin (HGB) level and recent reports on the effect apnoea has on spleen size and haematological parameters are contradictory. Therefore, this study aims to evaluate the effect apnoea training has on spleen size and haematological parameters.Methods: The breath-holding (BH) group was comprised of 12 local student-athletes with no BH exercise experience who performed BH jogging and BH jumping rope dynamic apnoea protocols, five times weekly for 8 weeks. The BH event duration was progressively increased as the apnoea tolerance of the athletes improved (20 to 35 s). The same training task was performed by the control group (n = 10) without BH. Spleen sizes were measured with an ultrasound system and a complete blood cell analysis was performed on the median cubital venous blood.Results: Spleen volume in the BH group increased from 109 ± 13 ml to 136 ± 13 ml (p < 0.001), and bulky platelets decreased from 70.50 ± 5.83 to 65.17 ± 5.87 (p = 0.034), but no changes were recorded for erythrocytes (p = 0.914), HGB (p = 0.637), PLTs (p = 0.346) and WBC (p = 0.532). No changes were recorded for the control group regarding spleen size or haematological parameters.Conclusion: Eight weeks of dry dynamic apnoea training increased spleen size and decreased the number of circulating bulky platelets in the athletes who were assessed in this study. However, the baseline RBC counts and HGB levels of the athletes were not altered by the training programme.

Chiral bipyridine/phenanthroline ligands have been applied as a class of unique ligands due to their rich coordination chemistry in catalysis. Herein, we synthesize 13 new C₂-symmetric chiral phenanthroline-bipyrroloimidazolone ligands (Phen-BPI) and 5 new C₂-symmetric chiral bipyridine-bipyrroloimidazolone ligands (BPy-BPI). These Bpy/Phen-BPI pincer ligands performed successfully in nickel-catalyzed asymmetric Friedel–Crafts alkylation of indoles with 2-enoylpyridine-1-oxides, affording the chiral products with up to 93% yield and 99% ee. The control experiment and metal complex L1–Ni crystal supported the dual activation manner, in which the tridentate Bpy/Phen-BPI ligand contained two nitrogen atoms of the pyridine unit and one tertiary amine group of the pyrroloimidazolone moiety coordinating with Ni(II) to activate the 2-enoylpyridine-1-oxides, and the tertiary amine group of the additional pyrroloimidazolone moiety as the H-bond acceptor activated the indoles through a NH-bonding interaction, resulting in the asymmetric transformation. This represented the first example showing that the Bpy/Phen ligand contained three nitrogen atoms coordinating with the metal, and the additional nitrogen atom acted as the H-bond acceptor.