Differences in Cardiometabolic Biomarkers between Elementary School-Age Latinx Children with Obesity versus Healthy Weight.

OBJECTIVES: Low-income Latinx youth are disproportionately affected by obesity, which results in an increased risk of cardiometabolic abnormalities. Biomarker tracking may be useful for the early identification of obesity comorbidities in young Latinx children. Hence, we aimed to compare cardiometabolic biomarkers between age- and sex-matched pairs of elementary school-aged Latinx children with obesity versus healthy weight. METHODS: This case-control study compared cardiometabolic biomarkers between 13 pairs of age- and sex-matched elementary school-age (median 6.5 years) Latinx children with obesity (body mass index for age ≥ 95th percentile) as compared with their healthy weight (between the 5th and 85th percentiles) counterparts. Anthropometric measures and a fasted venous blood sample were taken for the analysis of lipids, glycemic, inflammatory, endocrine, and hepatic markers. Group differences were tested by the Mann-Whitney U or χ2 test. RESULTS: Cases had higher insulin (P = 0.003), hemoglobin A1c (P = 0.002), triglycerides (P = 0.023), and C-reactive protein (P < 0.001) and lower high-density lipoprotein (P = 0.002). Hepatic markers were similar, with alanine aminotransferase elevated among both groups. CONCLUSIONS: The aforementioned biomarkers may be more sensitive to higher adiposity risk in this young Latinx population; however, elevated hepatic markers may indicate an ethnic/genetic predisposition to abnormal liver function. Research should be replicated in a larger group to confirm these findings.

Bidirectional Associations between Physical Activity and Sleep in Early-Elementary-Age Latino Children with Obesity.

Low-income Latino children are at high risk for obesity and associated comorbidities. Considering the health benefits of proper sleep habits and physical activity, understanding the patterns, or the relationship between these modifiable factors may help guide intervention strategies to improve overall health in this population. Thus, the purpose was to investigate bidirectional associations between physical activity and sleep among Latino children who are overweight/obese. Twenty-three children (boys, 70%; overweight, 17%; obese, 83%) (age 7.9 ± 1.4 years) wore activity monitors on their wrist for 6 consecutive days (comprising 138 total observations). Hierarchical linear modeling evaluated temporal associations between physical activity (light physical activity, LPA; moderate to vigorous activity, MVPA) and sleep (duration and efficiency). Although there was no association between MVPA and sleep (p > 0.05), daytime LPA was negatively associated with sleep duration that night (estimate ± SE = -10.77 ± 5.26; p = 0.04), and nighttime sleep efficiency was positively associated with LPA the next day (estimate ± SE = 13.29 ± 6.16; p = 0.03). In conclusion, increased LPA may decrease sleep duration that night, but increasing sleep efficiency may increase LPA the following day. Although further investigation is required, these results suggest that improving sleep efficiency may increase the level of physical activity reached among Latino children who are overweight/obese.

The structure of human CST reveals a decameric assembly bound to telomeric DNA.

The CTC1-STN1-TEN1 (CST) complex is essential for telomere maintenance and resolution of stalled replication forks genome-wide. Here, we report the 3.0-angstrom cryo-electron microscopy structure of human CST bound to telomeric single-stranded DNA (ssDNA), which assembles as a decameric supercomplex. The atomic model of the 134-kilodalton CTC1 subunit, built almost entirely de novo, reveals the overall architecture of CST and the DNA-binding anchor site. The carboxyl-terminal domain of STN1 interacts with CTC1 at two separate docking sites, allowing allosteric mediation of CST decamer assembly. Furthermore, ssDNA appears to staple two monomers to nucleate decamer assembly. CTC1 has stronger structural similarity to Replication Protein A than the expected similarity to yeast Cdc13. The decameric structure suggests that CST can organize ssDNA analogously to the nucleosome's organization of double-stranded DNA.