• Environmental Analysis Health and Toxicology
• /
• 제22권3호
• /
• pp.271-277
• /
• 2007

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are fully flurorinated organic compounds which are highly persistent in environment and accumulated in organism. These chemicals are released to the environment at their manufacture, during their use in industrial and consumer applications and from disposal after their use. The purpose of this study was to determine the effects of PFOA and PFOS on the freshwater flea (Moina macrocopa). Acute toxicity test and chronic toxicity test were performed for 2 days and 10 days, respectively. Acute toxicity was assessed on the basis of mortality, while chronic toxicity was assessed by fecundity as well as mortality. The acute toxicity studies on PFOA and PFOS showed that the values of $LC_{50}$ were $73.9\;mg/L\;and\;27.7\;mg/L$ respectively. In the chronic toxicity test, fecundity was reduced significantly at 24.1 mg/L of PFOA and 9.3 mg/L of PFOS, respectively. Conclusively, the results of this work suggest that Moina macrocopa could be a suitable model organism for screening and assessing of environmental pollutants in water.

• 한국토양비료학회지
• /
• 제39권5호
• /
• pp.280-284
• /
• 2006

농경지에 과거에 사용했거나 사용중인 살균제 14종에 대하여 농경지에 뿌려지는 추천사용량을 기준으로 토양표토처리법, 침지법, 여지접촉법으로 실험을 수행하였다. 그 결과 추천사용량에서 14종의 농약이 무처리와 통계적으로 유의성이 없는 것으로 나타나, 이런 농약들은 줄지렁이 치사에 영향을 주지 않는 것으로 판단되었다. 그러나 benomyl, Thiophanate-methyl, carbendazim 농약은 지렁이에게 독성이 높은 것으로 보고되어 있어 추가적인 검토가 필요하다고 생각된다.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제20권1호
• /
• pp.13-17
• /
• 2010

Ten numbers of plants, based on their medicinal value, were used to test their efficacy against virosis (caused by cytoplassmic polyhedrosis virus) in tasar silkworm, Antheraea mylitta Drury. in indoor rearing conditions. The aqueous extracts of leaf of Azadirichita indica (neem), Acharanthus aspera, Psoralea corylifolia, Asparagus racemosus, Adhatoda zelanica (Basak), Andrographis paniculata (Kalmegh), Moringa oilephera (sahjan), whole plant of Phyllanthus urinaria (Bhuiamla), Centella asiatica (Veng sag) and Curcuma longa (Haldi powder) in different concentrations were used for containment of virosis in silkworm larvae. The tasar silkworm larvae were orally inoculated with PIBs ($1\times10^6$) of AmCPV in $2^{nd}$ instar and treated with plant extracts in each instar ($2^{rd}$ instar onwards). The mortality due to virosis was recorded during larval period. The plant extracts, irrespective of their concentrations, were found effective in suppressing the virosis where P. urinaria reduced the virosis to 56.90% followed by A. paniculata (53.82%) and least in C. asiatica (5.15%). The lowest pooled larva mortality 36.99% was recorded in the treatment of P. urinaria. Comparatively higher larva mortality 39.91% was observed with the treatment of A. paniculata. The highest larva mortality in treatment was with C. asiatica (81.99%). In treated control larva mortality was 86.50%.

• 보건행정학회지
• /
• 제18권4호
• /
• pp.49-65
• /
• 2008

The single-item question of self-assessed health status has consistently been reported to be associated with mortality in some developed countries, even after controlling for a wide range of health measurements and known risk factors for. mortality. It was intended in this study to find out whether or not such a relationship would also be valid in Korea. This study examined the effect of point of reference year on. the, predictive validity of self-assessed health for mortality in 6-year follow-up period. we need to test the validity of the self-assessed health, as an indicator for assessing health status using Cox's proportional hazard model. For the analysis, we used the data from the 2nd (1999) to the 7th survey of "Korean Labor and Income Panel Study," and assessed relative risk of death based on subjective health state by tracing 11,366 people who replied to the question of self-assessed health state in the 2nd year. According to the result, those who reported poor self assessed health state in the 2nd year showed a relatively high death rate, and their relative risk of death was significantly higher. Such a relationship was accentuated if the predictive value of the 2nd survey result would be replaced by the average of the cumulative data on the past six years. Thus, it can be concluded that self-assessed health state is valid as an index for assessing Korean people's health status.

• 한국환경복원기술학회지
• /
• 제14권2호
• /
• pp.107-115
• /
• 2011

The purpose of the study is to analyze the environmental characteristics of fish acute toxicity that is dependent on the harmfulness of ACQ (Alkaline Copper Quat)-Treated Wood and Oryzias latipes mortality in a comprehensive way, provide objective verification method on the eco-toxicity and environment-friendliness of landscaping materials and methods, and utilize it as a basic datum for evaluation criteria. The main results are summarized as follows : 1. As a result of analysis on the harmfulness characteristics, each experimental plot showed different values respectively. In particular, it has been found that in proportion to the volume of testing materials, COD and Cu increases at a constant rate, compared to the input water. In the plot C with three testing materials, COD increased 67 times more than that of the input water, and Cu increased up to 12.36mg/L. 2. In case of fish toxicity, plot C, B, A all showed a mortality rate of 100%, indicating that fish toxicity is strong. In particular, the mortality rate of each plot within the initial time of one and a half hour showed clearly, which suggests that the fish toxicity is influenced by the increased concentration of hazardous substances depending on the volume ratio of testing materials. 3. As a result of comparison and analysis on the harmfulness and fish toxicity, the harmfulness showed different values on each experimental plot but, we found that the changing rate of values of toxicity of COD and Cu is mutually similar to that of mortality in the initial hour according to the experiment of fish toxicity, which shows that COD and Cu are major factors to increase fish toxicity.

• Journal of Korean Medical Science
• /
• 제33권50호
• /
• pp.299.1-299.13
• /
• 2018

Background: Sarcopenia is associated with a poor prognosis in patients with liver cirrhosis. However, it is not known whether the rate of skeletal muscle depletion is also associated with a poor prognosis. We investigated the prognostic impact of the rate of skeletal muscle depletion in patients with liver cirrhosis. Methods: We included retrospectively all patients with liver cirrhosis who underwent both multiple computed tomography scans and hepatic venous pressure gradient (HVPG) measurements. Results: A total of 131 patients with liver cirrhosis were enrolled. The mean age of the patients was 53.7 years and alcoholic liver disease was the most common cause (61.8%). Sixty-four patients (48.9%) were diagnosed with sarcopenia. The median changes in skeletal muscle area per year (${\Delta}SMA/y$) were -0.89%. During a median follow-up period of 46.2 months (range, 3.4-87.6), 45 patients (34.4%) died. In multivariate analyses, age, Child-Pugh score, HVPG, presence of sarcopenia and ${\Delta}SMA/y$ were independently associated with mortality. Cumulative mortality was significantly higher in patients with ${\Delta}SMA/y$ < -2.4% than those with ${\Delta}SMA/y{\geq}-2.4%$ (log-rank test, P < 0.001). Conclusion: Both the presence and rate of change of sarcopenia are independently associated with long-term mortality in patients with liver cirrhosis.

• 대한응급의학회지
• /
• 제29권5호
• /
• pp.455-464
• /
• 2018

Objective: Machine learning is not yet widely used in the medical field. Therefore, this study was conducted to compare the performance of preexisting severity prediction models and machine learning based models (random forest [RF], gradient boosting [GB]) for mortality prediction in pneumonia patients. Methods: We retrospectively collected data from patients who visited the emergency department of a tertiary training hospital in Seoul, Korea from January to March of 2015. The Pneumonia Severity Index (PSI) and Sequential Organ Failure Assessment (SOFA) scores were calculated for both groups and the area under the curve (AUC) for mortality prediction was computed. For the RF and GB models, data were divided into a test set and a validation set by the random split method. The training set was learned in RF and GB models and the AUC was obtained from the validation set. The mean AUC was compared with the other two AUCs. Results: Of the 536 investigated patients, 395 were enrolled and 41 of them died. The AUC values of PSI and SOFA scores were 0.799 (0.737-0.862) and 0.865 (0.811-0.918), respectively. The mean AUC values obtained by the RF and GB models were 0.928 (0.899-0.957) and 0.919 (0.886-0.952), respectively. There were significant differences between preexisting severity prediction models and machine learning based models (P<0.001). Conclusion: Classification through machine learning may help predict the mortality of pneumonia patients visiting the emergency department.

• Hip & pelvis
• /
• 제34권1호
• /
• pp.25-34
• /
• 2022

Purpose: Mortality rates following hip fracture surgery have been well-studied. This study was conducted to examine mortality rates in asymptomatic patients presenting for treatment of acute hip fractures with concurrent positive COVID-19(+) tests compared to those with negative COVID-19(-) tests. Materials and Methods: A total of 149 consecutive patients undergoing hip fracture surgery during the COVID-19 pandemic at two academic medical centers were reviewed retrospectively. Patients were divided into two groups for comparative analysis: one group included asymptomatic patients with COVID-19+ tests versus COVID-19- tests. The primary outcome was mortality at 30-days and 90-days. Results: COVID-19+ patients had a higher mortality rate than COVID-19- patients at 30-days (26.7% vs 6.0%, P=0.005) and 90-days (41.7% vs 17.2%, P=0.046) and trended towards an increased length of hospital stay (10.1±6.2 vs 6.8±3.8 days, P=0.06). COVID-19+ patients had more pre-existing respiratory disease (46.7% vs 11.2%, P=0.0002). Results of a Cox regression analysis showed an increased risk of mortality at 30-days and 90-days from COVID-19+ status alone without an increased risk of death in patients with pre-existing chronic respiratory disease. Conclusion: Factors including time to surgery, age, preexisting comorbidities, and postoperative ambulatory status have been proven to affect mortality and complications in hip fracture patients; however, a positive COVID-19 test result adds another variable to this process. Implementation of protocols that will promote prompt orthogeriatric assessments, expedite patient transfer, limit operating room traffic, and optimize anesthesia time can preserve the standard of care in this unique patient population.

• The Korean journal of internal medicine
• /
• 제39권2호
• /
• pp.295-305
• /
• 2024

Background/Aims: The prognosis of patients with idiopathic pulmonary fibrosis (IPF) and respiratory failure requiring mechanical ventilation is poor. Therefore, mechanical ventilation is not recommended. Recently, outcomes of mechanical ventilation, including those for patients with IPF, have improved. The aim of this study was to investigate changes in the use of mechanical ventilation in patients with IPF and their outcomes over time. Methods: This retrospective, observational cohort study used data from the National Health Insurance Service database. Patients diagnosed with IPF between January 2011 and December 2019 who were placed on mechanical ventilation were included. We analyzed changes in the use of mechanical ventilation in patients with IPF and their mortality using the Cochran-Armitage trend test. Results: Between 2011 and 2019, 1,227 patients with IPF were placed on mechanical ventilation. The annual number of patients with IPF with and without mechanical ventilation increased over time. However, the ratio was relatively stable at approximately 3.5%. The overall hospital mortality rate was 69.4%. There was no improvement in annual hospital mortality rate. The overall 30-day mortality rate was 68.7%, which did not change significantly. The overall 90-day mortality rate was 85.3%. The annual 90-day mortality rate was decreased from 90.9% in 2011 to 83.1% in 2019 (p = 0.028). Conclusions: Despite improvements in intensive care and ventilator management, the prognosis of patients with IPF receiving mechanical ventilation has not improved significantly.

• Journal of Trauma and Injury
• /
• 제24권2호
• /
• pp.89-94
• /
• 2011

Purpose: A few studies have assessed the factors affecting the prognoses for major trauma patients and those improving the circumstances when dealing with the trauma system. In that light, we analyzed factors, such as pre-hospital factors, the time to admission, the length of stay in the emergency department (ED) and emergency operation, influencing the outcomes for trauma patients. Methods: The patients who visited our emergency department from April 1, 2009, to February 29, 2011, due to major trauma were enrolled in the study. The inclusion criterion was a revised trauma score (RTS) < 7 or injury severity score (ISS) ${\geq}$ 16. We used reviews of medical records, to analyze each step of emergency medical care with respect to patients' sex, age, visit time and visit date. Continuous variables were described as a median with an interquartile range, and we compared the variables between the survival and the mortality groups by using the Mann-Whitney U test. Fisher's exact test was used for nominal variables. Using the variables that showed statistical significance in univariate comparisons, we performed a logistic regression analysis, and we tested the model's adequacy by the using the Hosmer-Lemeshow method. Results: A total of 261 patients with major trauma satisfied either the RTS score criterion or the ISS score criterion. Excluding 12 patients with missing data, 249 patients were included in this study. The overall mortality rate was 16.9%. Time to ED arrival, time to admission, time of ED stay, RTS, ISS, and visit date being a holiday showed statistically significant differences between the survival and the mortality groups in the univariate analysis. RTS, ISS, length of ED stay, and visit date being a holiday showed statistical significance in the multivariate analysis. Conclusion: The mortality rate did not show a significant relationship with the time to ED arrival, use of 119, on time to admission. Rather, it elicited a quite significant correlation with the trauma scoring system (RTS and ISS), the time of ED stay, and the visit date being a holiday.