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Interval training under hypoxia (IHT) is commonly used to enhance endurance exercise performance. However, previous studies examining hematologic changes related to the immune system that affect health and conditioning are lacking. This study aimed to evaluate the effects of IHT for 6-weeks on hematological parameters, hemodynamic function, and endurance exercise performance in amateur Korean female runners. Twenty healthy amateur Korean female runners (age: 24.85 ± 3.84 years) were equally assigned to normoxic training group (NTG) for interval training under normoxia (760 mmHg) and hypoxic training group (HTG) for interval training under hypobaric hypoxia (526 mmHg, 3000 m simulated altitude) according to their body composition and endurance exercise performance. All participants performed 120-min of training sessions, consisting of 20-min of warm-up, 60-min of interval training, and 20-min of cool-down. The training program was performed 3-days per week for 6-weeks. Warm-up and cool-down were performed for 20-min at 60% maximal heart rate (HRmax). The interval training sessions comprised 10 repetitions of interval exercise (5-min of exercise corresponding to 90–95% HRmax and 1-min of rest) on a treadmill. All participants underwent measurements of hematological parameters, hemodynamic function, and endurance exercise performance before and after training. Both groups showed a significant increase in erythropoietin (EPO) level and a decrease in monocyte abundance, with EPO showing a greater increase in the HTG than in the NTG. B cell abundance significantly increased in the NTG; hematocrit and neutrophil counts significantly increased, and lymphocyte counts significantly decreased in the HTG. The HTG showed a significant improvement in oxygen uptake, stroke volume index, and end-diastolic volume index compared to the NTG. In addition, both groups showed significant improvements in heart rate, end-systolic volume index, and cardiac output index. The maximal oxygen uptake and 3000 m time trial record were significantly improved in both groups, and the HTG showed a tendency to improve more than the NTG. In conclusion, the IHT was effective in enhancing endurance exercise performance through improved hemodynamic function. Furthermore, hematological parameters of immune system showed a normal range before and after training and were not negatively affected. [ABSTRACT FROM AUTHOR]

Background: As the population of Korea ages, interest in healthcare has increased. In particular, there is an increasing demand for immune-function improvement to prevent infectious diseases. Phellinus linteus (PL) has previously been shown to exert immune-enhancing and anticancer effects. We aim to evaluate whether PL mycelium extract, cultured from the PL KCTC0399BP strain, can increase immune function, as measured using blood-test indicators. This clinical trial protocol is designed as the main trial and is based on the results of a pilot study.Methods: This clinical trial is a randomized, double-blinded, placebo-controlled trial. Ninety-eight participants are enrolled and randomly divided into two groups: the experimental group (PL 1000 mg) and the control group (placebo). Participants are administered with experimental food or placebo for eight weeks. Blood tests are performed before trial initiation and 8 weeks later, at trial completion. Laboratory evaluation items are as follows: natural killer cell activity, tumor necrosis factor-α, interferon-γ, interleukin (IL)-1β, IL-2, IL-6, IL-12, immunoglobulin (Ig)G1, IgG2, and IgM. We will mainly use the full analysis dataset to statistically analyze the effectiveness of the treatment.Discussion: This study evaluates the effects of PL extract on immune function and will contribute to knowledge on the value of PL as an immune-function-boosting functional food.Trial Registration: Clinical Research Information Service (CRIS) of Korea CRIS-KCT0005460 . Registered on 12 October 2020. [ABSTRACT FROM AUTHOR]

Background: Although a significant number of the clinical features and pathophysiologic mechanisms of chronic rhinosinusitis (CRS) have been described, only a few studies have been published on characterization of CRS in the field of aging. Objective: We investigated the prevalence and risk factors of CRS in elderly (≥65 years old) Koreans using large-scale nationwide epidemiological data and compared the risk factors of elderly with those of younger adult participants (19–64 years old). Methods: Data from 25 529 participants who completed the 2008–2012 Korean National Health and Nutrition Examination Survey were analyzed. Diagnosis of CRS was done according to the EP3OS 2012 guideline for epidemiologic study. Risk factors of CRS were compared in the aspects of sociodemographics, general health behaviors, clinical characteristics, and comorbidities of participants. Results: The prevalence of CRS was significantly higher in 5590 elderly than in 19 939 younger adults (6.55% vs 5.69%; P =.016. Some variables of socioeconomic status and mental health in the adult group were associated with increased risk of CRS but did not show association in the elderly group. We observed a significant association between CRS prevalence and comorbid allergic rhinitis, asthma, and atopic dermatitis in both groups (P <.05). However, in the elderly group, the associations were significantly weaker with regard to allergic rhinitis (P -interaction =.03) and asthma (P -interaction =.002). Conclusion: These results suggest that elderly populations have distinct pathophysiology and clinical presentations from adult CRS, and management for elderly patients with CRS may require different or additional therapeutic approaches. [ABSTRACT FROM AUTHOR]

Abstract: Surf clam, Mactra veneriformis is one of the crucial fishery resources in Korea. This study was performed to examine the immune functions of the surf clam under the stress of water temperature changes at 10°C, 20°C or 30°C for 24h. Viable bacterial counts (VBC), total haemocyte count (THC), phagocytic activity, lysozyme activity, NRR times and SOD activity were assessed in three different water temperature groups. Clams held at 10°C decreased in THC, lysozyme activity and NRR times, but phagocytic activity was increased. The highest temperature (30°C) significantly increased in THC, whereas it decreased in phagocytic activity, lysozyme activity and NRR times. In clams maintained at 20°C, phagocytic activity, lysozyme activity and NRR times were increased whereas THC was somewhat decreased with respect to clams held at 30°C. However, water temperature changes did not elicit any alteration of VBC and SOD activity. The present study demonstrates that acute water temperature change affects the haemocytic and haemolymphatic functions, reducing immunosurveillance in stressed surf clam, M. veneriformis. [Copyright &y& Elsevier]