Selective advantage of mutant stem cells in human clonal hematopoiesis is associated with attenuated response to inflammation and aging.

Clonal hematopoiesis (CH) arises when hematopoietic stem cells (HSCs) acquire mutations, most frequently in the DNMT3A and TET2 genes, conferring a competitive advantage through mechanisms that remain unclear. To gain insight into how CH mutations enable gradual clonal expansion, we used single-cell multi-omics with high-fidelity genotyping on human CH bone marrow (BM) samples. Most of the selective advantage of mutant cells occurs within HSCs. DNMT3A- and TET2-mutant clones expand further in early progenitors, while TET2 mutations accelerate myeloid maturation in a dose-dependent manner. Unexpectedly, both mutant and non-mutant HSCs from CH samples are enriched for inflammatory and aging transcriptomic signatures, compared with HSCs from non-CH samples, revealing a non-cell-autonomous effect. However, DNMT3A- and TET2-mutant HSCs have an attenuated inflammatory response relative to wild-type HSCs within the same sample. Our data support a model whereby CH clones are gradually selected because they are resistant to the deleterious impact of inflammation and aging.

Trunk and hip muscle activation during yoga poses: Do sex-differences exist?

OBJECTIVE: To compare core activation during yoga between males and females. METHODS: Surface electromyography was used to quantify rectus abdominis (RA), abdominal obliques (AO), lumbar extensors (LE), and gluteus maximus (GMX) activation during four yoga poses. Data were expressed as 100% of a maximum voluntary isometric contraction. Mixed-model 2 × 2 analyses of variance with repeated measures were used to determine between-sex differences in muscle activity. RESULTS: Females generated greater RA activity than males during the High Plank (P < 0.0001) and Dominant-Side Warrior 1 (P = 0.017). They generated greater AO (P < 0.0001) and GMX (P = 0.004) activity during the High Plank (P < 0.0001). No between-sex EMG activity differences existed for the Chair and Upward Facing Dog. CONCLUSION: Findings have provided preliminary evidence for between-sex differences in muscle activation during yoga poses. Clinicians should consider such differences when prescribing yoga to improve muscle strength and endurance.

Trunk and hip muscle activation during yoga poses: Implications for physical therapy practice.

OBJECTIVE: To determine and compare activation of core muscles during yoga to traditional back exercises. METHODS: Surface electromyography was used to quantify activation of the rectus abdominis (RA), abdominal obliques (AO), lumbar extensors (LE), and gluteus maximus (GMX) during four yoga poses. Data were expressed as 100% of a maximum voluntary isometric contraction. Separate analyses of variance with repeated measures were used to compare muscle activity across each exercise. RESULTS: Subjects generated greater RA (P < 0.0001) and AO (P < 0.0001) activity during the Plank. They generated greater AO activity (P < 0.0001) during the Upward-Facing Dog than the Chair and Dominant-Side Warrior 1. LE activity was greatest (P < 0.0001) during the Chair. GMX activity was similar (P = 0.09) during all exercises. CONCLUSION: Yoga poses may help improve core endurance and strength. Clinicians may use these data when developing and implementing an evidence-based core exercise program for individuals who prefer a yoga treatment strategy.