In order to assess the efficiency of Percoll gradient centrifugation(PGC) as a method of sperm selection, we have examined morphological characteristics of spermatozoa from 40 teratozoospermic patients attending the Infertility Clinic of Inchon Gil Gerneral Hospital. Patients were divided into three groups according to percentage normal morphology in the fresh sample : group A(n=5), < 5% normal morphology : group B(n=21), 5~14% normal morphology : and group C(n=14), > 14% normal morphology. Morphology slides were perpared using Diff-Quik staining techniques and evaulated by Kruger strict criteria, under oil immersion at a magnification of X 1000, specific defects, head, neck and tail were assesed individualy. The results were as follows. 1. Following PGC, sperm samples with enhanced morphology were recovered for all groups. 2. For group A, PGC did not select a sample with significantly improved morphological characteristics. 3. Usually, sperm defects affected by PGC was head and neck. No significant difference was found for tail abnormality. In conclusion, Percoll gradient centrifugation is an efficient sperm preparation technique when the semen sample exhibits teratozoospermia, especially head or neck abnormality. However, in sample with < 5% normal form or tail abnormality, There is not significant improvement following PGC.
Centrifugation* ; Equidae ; Head ; Humans* ; Immersion ; Incheon ; Infertility ; Neck ; Semen ; Spermatozoa*

Several theories emphasize that aging is closely related to oxidative stress and disease. The formation of excess ROS can lead to DNA damage and the acceleration of aging. Vigna angularis is one of the important medicinal plants in Korea. We isolated vitexin from V. angularis and elucidated the lifespan-extending effect of vitexin using the Caenorhabditis elegans model system. Vitexin showed potent lifespan extensive activity and it elevated the survival rates of nematodes against the stressful environments including heat and oxidative conditions. In addition, our results showed that vitexin was able to elevate antioxidant enzyme activities of worms and reduce intracellular ROS accumulation in a dose-dependent manner. These studies demonstrated that the increased stress tolerance of vitexin-mediated nematode could be attributed to increased expressions of stress resistance proteins such as superoxide dismutase (SOD-3) and heat shock protein (HSP-16.2). In this work, we also studied whether vitexin-mediated longevity activity was associated with aging-related factors such as progeny, food intake, growth and movement. The data revealed that these factors were not affected by vitexin treatment except movement. Vitexin treatment improved the body movement of aged nematode, suggesting vitexin affects healthspan as well as lifespan of nematode. These results suggest that vitexin might be a probable candidate which could extend the human lifespan.
Acceleration ; Aging ; Caenorhabditis elegans* ; Caenorhabditis* ; DNA Damage ; Eating ; Heat-Shock Proteins ; Hot Temperature ; Humans ; Korea ; Longevity ; Oxidative Stress ; Plants, Medicinal ; Superoxide Dismutase ; Survival Rate

Background/Aims: For patients hospitalized with coronavirus disease 2019 (COVID-19) who require supplemental oxygen, the evidence of the optimal duration of corticosteroid is limited. This study aims to identify whether long-term use of corticosteroids is associated with decreased mortality. Methods: Between February 10, 2020 and October 31, 2021, we analyzed consecutive hospitalized patients with COVID-19 with severe hypoxemia. The patients were divided into short-term (≤ 14 days) and long-term (> 14 days) corticosteroid users. The primary outcome was 60-day mortality. We performed propensity score (PS) analysis to mitigate the effect of confounders and conducted Kaplan-Meier curve analysis. Results: There were 141 (52%) short-term users and 130 (48%) long-term corticosteroid users. The median age was 68 years and the median PaO2/FiO2 at admission was 158. Of the patients, 40.6% required high-flow nasal cannula, 48.3% required mechanical ventilation, and 11.1% required extracorporeal membrane oxygenation. The overall 60-day mortality rate was 23.2%, and that of patients with hospital-acquired pneumonia (HAP) was 22.9%. The Kaplan-Meier curve for 60- day survival in the PS-matched cohort showed that corticosteroid for > 14 days was associated with decreased mortality (p = 0.0033). There were no significant differences in bacteremia and HAP between the groups. An adjusted odds ratio for the risk of 60-day mortality in short-term users was 5.53 (95% confidence interval, 1.90–18.26; p = 0.003). Conclusions For patients with severe COVID-19, long-term use of corticosteroids was associated with decreased mortality, with no increase in nosocomial complications. Corticosteroid use for > 14 days can benefit patients with severe COVID-19.