Relationship Between Low Handgrip Strength and Chronic Kidney Disease: KNHANES 2014-2017.

OBJECTIVE: Accelerated loss of muscle mass is common in patients with chronic kidney disease (CKD). Various factors associated with CKD, such as nutritional deficiencies, metabolic acidosis, and chronic inflammation, contribute to muscle wasting. This study aimed to investigate the relationship between CKD and handgrip strength (HGS) in the Korean population. DESIGN AND METHODS: This is a population-based, cross-sectional study of a nationally representative sample of 18,765 patients aged ≥19 years from the Korea National Health and Nutrition Examination Survey in 2014-2017. We measured HGS using a digital hand dynamometer and determined the cutoff for low HGS by deriving -2 standard deviation values of sex-matched healthy young adults (19-39 years old). We defined CKD as eGFR <60 mL/min/1.73 m2 or the presence of CKD based on a self-reported questionnaire. RESULTS: The prevalence of CKD was 4.0% in the total population. The cutoff values for the low HGS were 29.5 kg for men and 16.8 kg for women. The prevalence of low HGS was 6.2% in patients without CKD, and 25.2% in patients with CKD. There was a significant correlation between HGS and eGFR in both men and women. In multivariate logistic regression adjusted by age group, diabetes, hypertension, and obesity, CKD showed an independent relationship with low HGS in both men (odds ratio [OR] 1.910, 95% confidence interval [CI] 1.468-2.485) and women (OR 1.570, 95% CI 1.202-2.052). CONCLUSIONS: The prevalence of low HGS was higher in patients with CKD. We suggest that the sarcopenia should be evaluated in patients with CKD.

Mononeuropathy multiplex associated with systemic vasculitis: A case report.

BACKGROUND: Vasculitis, a systemic disorder with inflammation of blood vessel walls, can develop broad spectrum of signs and symptoms according to involvement of various organs, and therefore, early diagnosis of vasculitis is challenging. We herein describe a patient who developed a special case of systemic vasculitis with mononeuropathy multiplex, rectal perforation and antiphospholipid syndrome (APS) presented with pulmonary embolism. CASE SUMMARY: A 61-year-old woman visited hospital with complaints of myalgia and occasional fever. She was initially diagnosed as proctitis and treated with antibiotics, however, there was no improvement. In addition, she also complained right foot drop with hypesthesia, and left 2nd and 3rd finger tingling sensation. She underwent nerve conduction study for evaluation, and it revealed sensorimotor polyneuropathy in the left arm and bilateral legs. Subsequent sural nerve biopsy strongly suggested vasculitic neuropathy. Based on nerve biopsy and clinical manifestation, she was diagnosed with vasculitis and treated with immuno-suppressive therapy. During treatment, sudden rectal perforation and pulmonary thromboembolism occurred, and further laboratory study suggested probable concomitant APS. Emergency Hartmann operation was performed for rectal perforation, and anti-coagulation therapy was started for APS. After few cycles of immunosuppressive therapy, tingling sensation and weakness in her hand and foot had been partially recovered and vasculitis was considered to be stationary. CONCLUSION: Vasculitis can be presented with a variety of signs and symptoms, therefore, clinicians should always consider the possibility of diagnosis.

Handgrip Strength in the Korean Population: Normative Data and Cutoff Values.

BACKGROUND: We aimed to report the age- and sex-specific normative data of Korean handgrip strength (HGS) and to establish the cutoffs values of low HGS in Korean populations. METHODS: We analyzed the HGS data of 23,716 Koreans (10,793 men and 12,923 women) from the Korea National Health and Nutrition Examination Survey from 2014 to 2017. The means with standard deviations (SDs) of HGS were calculated for each 5-year interval starting from 10 years of age. To determine the relationship between HGS and body mass index (BMI), correlation analysis was also performed. The sex-specific cutoff values for low HGS were presented by deriving the -2 SD values of healthy young adults. RESULTS: The mean HGS was 39.5±9.3 kg in men and 24.4±5.3 kg in women. The mean HGS increased from 10 to 39 years and peaked at 35-39 years in both men (46.0±7.2 kg) and women (27.2±4.6 kg). Men showed a higher correlation between HGS and BMI (r=0.378) than did women (r=0.134). The cutoff values for low HGS were 29.6 kg for men and 16.8 kg for women for -2 SD below the reference for healthy young adults. CONCLUSION: In Koreans, the mean HGS peaked at 35-39 years in both men and women, and the aging curve of HGS was steeper in men than in women. The cutoff values for low HGS were 29.6 kg and 16.8 kg for men and women, respectively.

Transcriptional response according to strength of calorie restriction in Saccharomyces cerevisiae.

To characterize gene expression that is dependent on the strength of calorie restriction (CR), we obtained transcriptome at different levels of glucose, which is a major energy and carbon source for budding yeast. To faithfully mimic mammalian CR in yeast culture, we reconstituted and grew seeding yeast cells in fresh 2% YPD media before inoculating into 2%, 1%, 0.5% and 0.25% YPD media to reflect different CR strengths. We collected and characterized 160 genes that responded to CR strength based on the rigorous statistical analyses of multiple test corrected ANOVA (adjusted p0.7). Based on the individual gene studies and the GO Term Finder analysis of 160 genes, we found that CR dose-dependently and gradually increased mitochondrial function at the transcriptional level. Therefore, we suggest these 160 genes are markers that respond to CR strength and that might be useful in elucidating CR mechanisms, especially how stronger CR extends life span more.

A cargo-sorting DNA robot.

Two critical challenges in the design and synthesis of molecular robots are modularity and algorithm simplicity. We demonstrate three modular building blocks for a DNA robot that performs cargo sorting at the molecular level. A simple algorithm encoding recognition between cargos and their destinations allows for a simple robot design: a single-stranded DNA with one leg and two foot domains for walking, and one arm and one hand domain for picking up and dropping off cargos. The robot explores a two-dimensional testing ground on the surface of DNA origami, picks up multiple cargos of two types that are initially at unordered locations, and delivers them to specified destinations until all molecules are sorted into two distinct piles. The robot is designed to perform a random walk without any energy supply. Exploiting this feature, a single robot can repeatedly sort multiple cargos. Localization on DNA origami allows for distinct cargo-sorting tasks to take place simultaneously in one test tube or for multiple robots to collectively perform the same task.

Association between Exposure to Smartphones and Ocular Health in Adolescents.

PURPOSE: Smartphone use has dramatically increased in recent years. Smartphones may have adverse health effects, particularly on the eyes, because users stare at the screen for a much longer time than they do with ordinary mobile phones. The objective of this study was to elucidate the relationship between smartphone use and ocular symptoms among adolescents. METHODS: Information on smartphone use and ocular symptoms (blurring, redness, visual disturbance, secretion, inflammation, lacrimation and dryness) related to eye fatigue and strain from 715 adolescent subjects from three cities in Korea was obtained using a structured questionnaire. Ocular health was scored using number of ocular symptoms. Odds ratios (ORs), 95% confidence intervals (95% CIs) and p-values for ocular symptoms were calculated with binomial and multinomial logistic regression models. RESULTS: Higher prevalence rates for ocular symptoms were observed in groups with greater exposure to smartphones (p < 0.05). Longer daily smartphone use was associated with a higher likelihood of having multiple ocular symptoms (5-7 symptoms out of 7 symptoms; p = 0.005). Excessive/intermittent use (>2 hours daily and ≤2 hours continuously) and excessive/persistent use (>2 hours daily and >2 hours continuously) compared to shorter use (<2 hours daily) were associated with multiple ocular symptoms (OR 2.18, 95% CI 1.09-4.39; OR 2.26, 95% CI 1.11-4.57, respectively). A higher lifetime exposure to smartphones was associated with a higher likelihood of having multiple ocular symptoms (OR 3.05, 95% CI 1.51-6.19; p = 0.001). CONCLUSION: Increasing exposure to smartphones can have a negative impact on ocular health in adolescents.