• Journal of Chest Surgery
• /
• v.57 no.1
• /
• pp.36-43
• /
• 2024

Background: Coronavirus disease 2019 (COVID-19) can lead to acute respiratory failure, which frequently necessitates invasive mechanical ventilation and extracorporeal membrane oxygenation (ECMO). However, the limited availability of ECMO resources poses challenges to patient selection and associated decision-making. Consequently, this retrospective single-center study was undertaken to evaluate the characteristics and clinical outcomes of patients with COVID-19 receiving ECMO. Methods: Between March 2020 and July 2022, 65 patients with COVID-19 were treated with ECMO and were subsequently reviewed. Patient demographics, laboratory data, and clinical outcomes were examined, and statistical analyses were performed to identify risk factors associated with mortality. Results: Of the patients studied, 15 (23.1%) survived and were discharged from the hospital, while 50 (76.9%) died during their hospitalization. The survival group had a significantly lower median age, at 52 years (interquartile range [IQR], 47.5-61.5 years), compared to 64 years (IQR, 60.0-68.0 years) among mortality group (p=0.016). However, no significant differences were observed in other underlying conditions or in factors related to intervention timing. Multivariable analysis revealed that the requirement of a change in ECMO mode (odds ratio [OR], 366.77; 95% confidence interval [CI], 1.92-69911.92; p=0.0275) and the initiation of continuous renal replacement therapy (CRRT) (OR, 139.15; 95% CI, 1.95-9,910.14; p=0.0233) were independent predictors of mortality. Conclusion: Changes in ECMO mode and the initiation of CRRT during management were associated with mortality in patients with COVID-19 who were supported by ECMO. Patients exhibiting these factors require careful monitoring due to the potential for adverse outcomes.

• Pediatric Infection and Vaccine
• /
• v.24 no.3
• /
• pp.146-151
• /
• 2017

Purpose: We analyzed the risk factors affecting readmission of children with pneumonia. Methods: We retrospectively analyzed the medical records of pediatric patients admitted to the Department of Pediatrics at the Jeonju Presbyterian Medical Center from January 2007 to August 2016. We classified patients who were readmitted with pneumonia within 30 days of discharge as the readmission group and patients who were admitted with pneumonia for the first time as the first admission group. Results: Among 158 patients, the study (readmission) group included 82 patients and the control (first admission) group included 76 patients. Age, the percentage of segmented neutrophils and lymphocytes, the number of admissions in the last 12 months, the associated diseases (respiratory diseases such as asthma), and the affection of the right upper lung were analyzed as risk factors for readmission. However, based on a regression analysis, only age and associated diseases were found to be significant risk factors. The rate of readmission increased with younger age. When there were associated diseases, the rate of readmission also increased. Conclusions: Young age and associated diseases were significant risk factors for readmission for patients with pediatric pneumonia. When pediatric patients are admitted with pneumonia, if they are young and/or have associated diseases, a comprehensive approach is needed to reduce the rate of readmission with careful consideration of precise examination, treatment, timing of discharge, and follow-up.

• Nutritional Sciences
• /
• v.6 no.3
• /
• pp.160-166
• /
• 2003

To examine the evidence that wheat bran is protective against breast cancer development and that its main mechanism of action is by modulating estrogen metabolism. This review explores the role of different experimental factors on the anticancer effects of wheat bran and the relationship of changes to estrogen metabolism by wheat bran on breast cancer risk The timing of the experimental diets in relation to carcinogen administration, the length of feeding of the experimental diets, and the level of dietary fat had an impact on the effectiveness of different doses of wheat bran in reducing breast carcinogenesis. Wheat bran supplementation resulted in significant reductions in human plasma estrogen levels but not in that of animals tested. The change in excretory metabolism of estrogen by wheat bran feeding in animals was not related to any of the tumor indices measured. The protective effect of wheat bran in breast carcinogenesis is greatest at the promotional phase and when supplemented in a high fat diet. Doses of wheat bran in the 9-12% range in diet have been consistently protective. The inconsistency observed with higher doses of wheat bran may be dependent on the animal model used. Although wheat bran's inhibitory effects on tumor growth may involve changes to estrogen metabolism, the fiber and phytochemical components of wheat bran may also act through estrogen-independent mechanisms. For a better understanding of the effect of wheat bran on breast carcinogenesis, studies comparing the effects of different wheat bran components both alone and in combination need to be performed.

• Journal of the Korean Society for Precision Engineering
• /
• v.24 no.9
• /
• pp.52-59
• /
• 2007

Fuel injection system greatly affects the performance of a direct injection diesel engine. A common rail injection system was introduced to satisfy the stringent emission standards, low fuel consumption, and low noise in recent years. The performance of a common-rail fuel injection system is strongly influenced by the injector characteristics. The common rail injector has evolved in order to improve its injection performance. The piezo-actuated injector is more suitable for common rail injection system due to its fast response and is expected to replace current solenoid-operated injector. In this study, nonlinear mathematical models are proposed for the solenoid-operated and the piezo-actuated injectors for control applications. Based on these models, the injection rate, which is one of the most important factors for the injection characteristics, is estimated using sliding mode observer. The simulation results and the experimental data show that the proposed sliding mode observers can effectively estimate the injection timing and the injection rate for both common-rail injectors.

• Radiation Oncology Journal
• /
• v.34 no.4
• /
• pp.290-296
• /
• 2016

Purpose: Radiotherapy (RT) is considered a mainstay of treatment in parameningeal rhabdomyosarcoma (PM-RMS). We aim to determine the treatment outcomes and prognostic factors for PM-RMS patients who treated with RT. In addition, we tried to evaluate the adequate dose and timing of RT. Materials and Methods: Twenty-two patients with PM-RMS from 1995 to 2013 were evaluated. Seven patients had intracranial extension (ICE) and 17 patients had skull base bony erosion (SBBE). Five patients showed distant metastases at the time of diagnosis. All patients underwent chemotherapy and RT. The median radiation dose was 50.4 Gy (range, 40.0 to 56.0 Gy). Results: The median follow-up was 28.7 months. Twelve patients (54.5%) experienced failure after treatment; 4 local, 2 regional, and 6 distant failures. The 5-year local control (LC) and overall survival (OS) were 77.7% and 38.5%, respectively. The 5-year OS rate was 50.8% for patients without distant metastases and 0% for patients with metastases (p < 0.001). Radiation dose (<50 Gy vs. ${\geq}50Gy$) did not compromise the LC (p = 0.645). However, LC was affected by ICE (p = 0.031). Delayed administration (>22 weeks) of RT was related to a higher rate of local failure (40.0%). Conclusion: RT resulted in a higher rate of local control in PM-RMS. However, it was not extended to survival outcome. A more effective treatment for PM-RMS is warranted.

• Journal of Ecology and Environment
• /
• v.31 no.3
• /
• pp.207-211
• /
• 2008

We investigated the leaf demography of a temperate woody liana, Akebia trifoliata, in a temperate forest in Japan, Akebia is semi-evergreen: some leaves are shed before winter, while others remain through the winter. Previous studies of semi-evergreen species found that variation in leaf life span was caused by variation in the timing of leaf emergence, Leaves that appeared just before winter over-wintered, while leaves appearing earlier were shed, However, it is unclear whether leaves of the same cohort (i.e., leaves that appear at the same time within a single site) show variation in life span under the effect of strong seasonality. To separate variation in life span among the leaves in each cohort from variation among cohorts, we propose a new method - the single leaf diagram, which shows the emergence and death of each leaf. Using single leaf diagrams, our study revealed that Akebia leaves within a cohort showed substantial variation in life span, with some over-wintering and some not. In addition, leaves on small ramets in the understory showed great variation in life span, while leaves on large ramets, which typically reach higher positions in the forest canopy, have shorter lives, As a result, small ramets were semi-evergreen, whereas large ramets were deciduous, The longer lives of leaves on small ramets can be interpreted as a shade-adaptive strategy in understory plants.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.22 no.6
• /
• pp.120-127
• /
• 2014

Robustness and controllability are the key factors in internal combustion engine commercialization. This study focuses on the combustion strategy to commercialize the low temperature diesel combustion technology. Various LTC combustion methods such as PPCI, MK and highly diluted mixing controlled LTC were conducted on 6.0L heavy duty diesel engine. To find the best feasible LTC strategy, emission level, fuel consumption and combustion safety during the combustion mode change were considered. Experiments were carried out under various engine operating conditions; engine speed & load, EGR level, injection timing. Finally, this study suggests realizable LTC combustion strategy; moderate EGR level and slight early injection are possible to considerably lower PM, NOx emission and expand LTC operating range up to 50% load without CO and HC emission.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.9 no.5
• /
• pp.89-95
• /
• 2001

Recently GDI(Gasoline Direct Injection) engine is spotlighted to achieve higher thermal efficiency under partial loads and better performance at full loads. To realize this system, it is essential to make both stratified combustion and homogeneous combustion. When compared to PFI(Port Fuel Injection) engine, GDI engine needs more complicated control and optimal design with injection system. In addition, spray pattern must be optimized according to injection timing because ambient pressure in combustion chamber is also varied. Thus spray structure should be analyzed in details to meet various conditions. In this experimental study, two types of visualization system were developed to simulate compression stroke and intake stroke, respectively. With an increase of the ambient pressure, the penetration length tends to decrease due to rising resistance caused by the drag force of the ambient air. Spray characteristics impinged on the piston has a significant effect on mixture stratification around the spark plug. These results provide the information on macroscopic spray structure and design factors far developing GDI injector.

• Korean Journal of Applied Biomechanics
• /
• v.20 no.1
• /
• pp.49-55
• /
• 2010

The purpose of the study was to analyze kinetic factors required to the three-point jump shot of the basketball games through 3-D analysis and ground reaction force(GRF) analysis. Six university male players participated in this study. The results of the study were showed that (1) resultant velocity in the center of mass(COM) was $0.84{\pm}0.27\;m/s$ since a player didn't shot a ball in the highest peak and shot ball at the moment of going up forward and vertical movement. Therefore, it is necessary to find a proper timing to shot a ball; (2) the angular velocity was largely increased in upper arm and fore arm out of the upper-limb segments and the hands had the largest angular velocity since the body is in a fixed situation and angular speed is rapidly increased by the wrist' snap with the rapid movement of upper arm and forearm at the time of release a ball; (3) it is judged that a player can shot a ball at the accurate and high release point when the player collects power vertically to the maximum by keeping GRF to the right and the rear in a proper way and by keeping the body's balance so that a large power may not be dispersed.

• Korean Journal of Clinical Pharmacy
• /
• v.27 no.4
• /
• pp.199-206
• /
• 2017

As the population ages, the life of women after menopause becomes much longer than the past, and the quality of life of old age becomes increasingly principal issue. There is a period that women experience the physical symptoms of menopause, although there are differences in degree, and the management of this period is a suitable time for women to improve their quality of life. According to the menopausal hormone therapy (MHT) and Timing Hypothesis, which has been proven in the Kronos Early Estrogen Prevention Study (KEEPS) and the Early vs Late Intervention Trial with Estradiol (ELITE) study, a relatively young woman before and after menopause can benefit from long-term beneficial effects such as prevention of osteoporosis and cardiovascular disease by early initiation of hormone therapy to alleviate menopausal symptoms. MHT should be considered for all women in healthy (without other important diseases) menopausal years, expecting to improve their quality of life through symptom relief in menopausal women and, in the long term, to prevent cardiovascular disease and osteoporosis. When applying hormone therapy to individuals, it is necessary to establish various treatment strategies according to the menopausal symptoms of individual patients (individualization of treatment) and judge the suitability of clinical application.