• Parasites, Hosts and Diseases
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• v.27 no.2
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• pp.101-108
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• 1989

This study was performed to observe the role of Pneumocystis carinii as an etiologic agent of interstitial pneumonia in immunocompromised hosts. Total 90 male Sprague-Dawley rats, approxi. mately 150-180 g, were used. Fifteen of them were used as control group and remaining 75 (5 groups) were as immunosuppression groups; group 1 received prednisolone (25 mg/kg twice weekly) only; group 2 Prednisolone and tetracycline (75 mk/kg/day) ; group 3 Prednisolone, tetracycline and trimethoprim-sulfamethoxasole (50~250 mg/kg/day) : group 4 prednisolone and trimethoprim-sulfamethoxasole; and group 5 prednisolone and griseofulvin (300 mg/kg/day) until death. The survival days of each group rat were calculated, and upon death their lungs were removed immediately and then stamp smears were prepared and stained by Giemsa or toluidine blue O. For histopathologic observation, lungs were fixed in 10% formalin, cut into sections and stained with Gomori's methenamine silvei, hematoxylin-rosin, and Brovkn & Brenn stain. The results obtained were as follows: 1. The mean survival time of each group rat was 19.3$\pm$5.2 days (group 1), 41.1$\pm$14.0 days (group 2), 50.5$\pm$18.4 days (group 3), 43.0$\pm$22.9 days (group 4) or 21.8$\pm$5.1 days (group 5). Significant differences were noted between group 1 and group 2(p<0.01), group 1 and group 3 (p<0.01), and group 1 and group 4 (p<0.01), which represented bacterial infections were most fatal in immunocompromised rats. Group 5 revealed no difference in the survival day from group 1, while significant differences were noted between group 2 and group 5(P<0.01), group 3 and group 5(p<0.01), and group 4 and group 5(p<0, 01), which represented little importance of fungal infection as the cause of death of the rats. 2. The first fatality due to p. carinii pneumonia occurred 17 days after the beginning of the immunosuppression. The occurrence rate of P. carinii pneumonia in the decreasing order was 92.9% (group 3), 80.0% (group 2 and group 5), 78.6% (group 4) and 33.3% (group 1). With regard to the pathological stage of P. carinii pneumonia, the stage 1 was 11.3%, the stage 2, 28.3%, and the stage 3, 60.4%. 3. Viewing from the duration of immunosuppression, bacterial pneumonia chieay appeared in 1 month, mixed infections (P. carinii and bacteria, or p. carinii and fungi) in 1~2 months, and pure P. carinii pneumonia after 2 months. The present study revealed that P. carinii pneumonia was the most important cause of death of immunocompromised rats later than 1 month after the start of immunosuppression.

• The Korean Journal of Pesticide Science
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• v.18 no.1
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• pp.14-20
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• 2014

This study is aimed to search the possibility of developmental toxicity test using the zebrafish from the pesticide. We selected herbicides alachlor and butachlor, reported for fish toxicity, and insecticide fipronil reported for the high fish toxicity and the honey bee risk among the pesticides with high usability for the examples of the pesticides in this experiment. In this study, we showed those effects on the zebrafish embryo development by exposing different kinds of pesticide with different concentration and exposed time periods. As a result, the rates of hatching and abnormality of the zebrafish embryo after treatments of alachlor were increased in 24-48 hpf group, and the juvenile fishes in every group exposed to $40{\mu}M$ or more of alachlor displayed sever morphological changes such as bent tails, edema and activity failures. In case of the butachlor, the rates of hatching and the abnormality in 24-48 hpf group were higher than the other groups exposed in different time periods. The fatality before hatching was high in $40{\mu}M$ or more of butachlor treatment, and entire zebrafish embryos in 48 hpf group died before hatching. All the living juvenile fishes showed morphological changes as like as the treatment of alachlor. The rate of hatching and the survival of the zebrafish embryo by the fipronil were higher than other pesticides. However, morphological changes such as bent tails were observed from the most of living juvenile fishes. Therefore, the effects of three different pesticides with different concentrations and exposing time periods on the development of zebrafish embryos showed that all the pesticides effects were proportional to the concentration, and exposing time periods may cause the morphological abnormality.

• Tuberculosis and Respiratory Diseases
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• v.47 no.2
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• pp.184-194
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• 1999

Backgrounds : The advent of penicillin has led to the marked reduction in the mortality from pneumococcal bacteremia, however, the mortality is still relatively high in this post-antibiotic era. Actually the prevalence of infection due to penicillin-resistant penumococci is increasing worldwide, and it is especially high in Korea due to irrelevant use of antibiotics. So, the high mortality of pneumococcal sepsis might be related to the emergence of penicillin-resistant strains, however, many other antibiotics, which eradicate pneumococci effectively, are available in these days. This has led us to suspect the role of penicillin-resistance in the high mortality rate. In this study, we evaluated the effect of penicillin resistance on the mortality of patients with penumococcal bacte remia. Methods: The study population consisted of 50 adult patients with penumococcal bacteremia who were admitted between Jan, 1990 and July, 1997. Medical records were analyzed retrospectively. Results: Most of the patients (96%) had underlying diseases. The most common local disease associated with pneumococcal bacteremia was pneumonia (42%), which was followed by spontaneous bacterial peritonitis (14%), cholangitis (10%), meningitis (8%), liver abscess (4%), pharyngotonsillitis (4%), sinusitis (2%) and cellulitis (2%). While the overall case-fatality rate in this study was 24%, it was higher when peumococcal bacteremia was associated with pneumonia (42%) or meningitis (50%). The rate of penicillin resistance was 40%, which was increased rapidly from 1991. The rate of penicillin resistance was significantly higher in patients with the history of recent antibiotics use and hospitalization within 3 months respectively. The clinical manifestations, that is, age, severity of underlying diseases, nosocomial infection, associated local diseases, and the presence of shock or acute renal failure were not statistically different between the patients with penicillin-resistant and -sensitive pneumococcal bacteremia. The mortality of patients infected with penicillin-resistant pneumococci was not statistically different from those with penicillin-sensitive pneumococcal bacteremia. Conclusion: Penicillin resistance is not associated with high mortality in adult patients with pneumococcal bacteremia. As the overall mortality is high, active penumococcal vaccination is recommended in patients with high risk of infection.

• Pediatric Infection and Vaccine
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• v.10 no.2
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• pp.208-214
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• 2003

Purpose : We performed a retrospective study on bacterial meningitis in children, pertaining to the causative organisms, bacterial resistance to antibiotics and the effect of recent introduction of Haemophilus influenzae type b(Hib) vaccine. Methods : We analysed the forty-three cases of bacterial meningitis which had been treated at the Inha University Hospital from June 1996 to June 2003. Results : Nineteen cases(44.2%) of them were infants younger than 2 months of age, and 29 cases(67.5%) younger than 1 year of age. The common causative organisms under 2 months of age were group B streptococcus(GBS)(47.4%), E. coli(21.1%), and Klebsiella pneumoniae(21.1%). In the age group beyond 2 months of age, S. pneumoniae were seen in 50 %, H. influenzae in 16.7% and N. meningitidis in 16.7%. All of the five cases of Hib meningitis had not been vaccinated for Hib. There has been no Hib meningitis cases since 2001. Overall fatality rate was 4.5%, and complication occurred in 39%. Complications was significantly less frequent in patients resumed to be treated within 48 hours after onset compared to after 48 hours after onset. Penicillin resistance of S. pneumoniae and GBS isolated among bacterial meningitis cases was high. Conclusion : Timing of treatment after the onset of the disease appeared the most important factor for prognosis of bacterial meningitis. The cases of H. influenzae meningitis have decreased probably due to Hib vaccination.

• Journal of Trauma and Injury
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• v.20 no.2
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• pp.57-64
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• 2007

Purpose: Clinically, acute respiratory distress syndrome (ARDS) occurs within 72 hours after acute exposure of risk factors. Because of its high fatality rate once ARDS progresses, early detection and management are essential to reduce the mortality rate. Accordingly, studies on early changes of ARDS were started, and serum ferritin, as well the as injury severity score (ISS), which has been addressed in previous studies, thought to be an early predictive indicator for ARDSMethods: From March 2003 to March 2005, we investigated 50 trauma patients who were admitted to the intensive care unit in Dongguk University Medical Center, Gyeongju. The patients were characterized according to age, sex, ISS, onset of ARDS, time onset of ARDS, serum ferritin level (posttraumatic $1^{st}\;&\;2^{nd}$ day), amount of transfused blood, and death. Abdominal computed topography was performed as an early diagnostic tool to evaluate the onset of ARDS according to its diagnostic criteria. The serum ferritin was measured by using a $VIDAS^{(R)}$ Ferritin (bioMeriux, Marcy-1' Etoile, France) kit with an enzyme-linked fluorescent assay method. For statistical analysis, Windows SPSS 13.0 and MedCalc were used to confirm the probability of obtaining a predictive measure from the receiver operating characteristics (ROC) curve. Results: The ISS varied from 14 to 66 (mean: 33.8) whereas the onset of ARDS could be predicted with the score above 30 (sensitivity: 90.0%, specificity: 60.0%, p<0.05). On the posttraumatic $1^{st}$ day, the serum ferritin levels were measured to be from 31 mg/dL to 1,200 mg/dL (mean: 456 mg/dL), and the onset of ARDS could be predicted when the value was over 340 mg/dL (sensitivity: 80.0%, specificity: 65.0%, p<0.05). On the posttraumatic $2^{nd}$ day, the serum ferritin levels were measured to be from 73 mg/dL to 1,200 mg/dL (mean: 404 mg/dL), and the onset of ARDS could be predicted when the value was over 627 mg/dL (sensitivity: 60.0%, specificity: 92.5%, p<0.05). The serum ferritin levels and the ISS were significantly higher on the posttraumatic $1^{st}$ and $2^{nd}$ day in the ARDS group, suggesting that they are suitable indices predicting the onset of ARDS, however relationship between the serum ferritin levels and the ISS was not statistically significant. Conclusion: In this study, we discovered increasing serum ferritin levels in multiple- trauma patients on the posttraumatic $1^{st}$ & $2^{nd}$ day and concluded that both the serum ferritin level and the ISS were good predictors of ARDS. Although they do not show statistically significant relationship to each other, they can be used as independent predictive measures for ARDS. Since ARDS causes high mortality, further studies, including the types of surgery and the methods of anesthesia on a large number of patients are essential to predict the chance of ARDS earlier and to reduce the incidence of death.

• Pediatric Infection and Vaccine
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• v.24 no.3
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• pp.160-167
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• 2017

Purpose: Because children with asplenia have an increased risk of fulminant infection associated with a high fatality, chemoprophylaxis, and vaccinations against encapsulated bacteria are recommended. However, there have been few reports of the burden of severe bacterial infection and the current status of chemoprophylaxis and immunization among children with asplenia in Korea. Methods: We conducted a retrospective study including children with asplenia who were treated at our institute between January 1997 and December 2016. Results: From a total of 213 children with asplenia, 114 (53.5%) had congenital asplenia and 58 (27.2%) had functional asplenia. The remaining 41 (19.3%) had acquired asplenia with the median age at splenectomy being 12.2 years (range, 5.0 to 16.9 years); the most common cause of splenectomy was hereditary spherocytosis (39.0%). The chemoprophylaxis rate was 16.4%. The immunization rates were 44.1% for pneumococcus, 53.0% for Haemophilus influenzae type B, and 10.7% for meningococcus. The incidence of invasive bacterial infection among children with asplenia was 0.28/100 person-year; a total of six episodes (2.8%) were observed in five patients with congenital asplenia and one patient with functional asplenia. The median age for these infections was 15 months (range, 4 to 68 months). Five of the six episodes were bacteremia, and the other was meningitis. The most common pathogen was Streptococcus pneumoniae (n=3), followed by H. influenzae (n=1). Three of the six patients (50.0%) died, all of whom had pneumococcal bacteremia. None of the six had chemoprophylaxis or proper vaccinations. Conclusions: Although there is an increased risk of a severe infection proper vaccinations and chemoprophylaxis are still lacking. Physicians should be encouraged to implement appropriate chemoprophylaxis and immunizations for patients with asplenia.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.5
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• pp.815-825
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• 2017

Visibility of lane marking is impaired at night or in the rain, which thereby threatens traffic safety. Recently, various studies and technologies have been developed to improve lane marking visibility, such as the extension of lane marking life expectancy (up to 1.5 times), improvement of lane marking equipment productivity, improvement of lane marking visibility by applying phosphorescent material mixed paint. Cost-benefit analysis was performed with considering various benefit items that can be expected. About 45% of traffic accidents would be prevented by improving lane marking visibility. Additionally, accident reduction benefit and traffic congestion reduction benefit were calculated as much as 246 billion KRW per year and 12 billion KRW per year, respectively, by reducing repaint cycle due to enhanced durability. 45 billion KRW per year is expected to reduced with improved lane detection performance of autonomous vehicle. Meanwhile, total increased cost when introducing phosphorescent material mixed paint to 91,195km of nationwide road is identified as 1922 billion KRW per year. However, economic feasibility could not be secured with 0.16 of cost-benefit ratio when applied to the road network as a whole. In case of "Accident Hot Spot" analyzing section window (400m), one or more fatality or two or more injured (one or more injured in case of less than 2 lanes per direction) per year were caused by pavement marking related accident, economic feasibility was secured. In detail, 3.91 of cost-benefit ratio is estimated with comparison of the installation cost for 5,697 of accident hot spot and accident reduction benefit. Some limitations and future research agenda have also been discussed.

• Journal of agricultural medicine and community health
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• v.26 no.1
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• pp.65-79
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• 2001

Cerebrovascular disease(CVD) is one of the major causes of death in Korea as well as most countries in the world and the disease gives great burden to humans socio-economically due to its high fatality and common occurrence of disability as the sequelae. This study was performed to investigate the utilization of western hospital(WH) or oriental hospital(OH) due to CVD and compare the type and the clinical characteristics of patients with CVD between WH and OH located in Kwangju City, Chonnam Province and Chonbuk Province. We reviewed the medical records of 1,070 patients who were discharged from 12 WIT and 6 OH from January to March, 2000 and confirmed for the diagnosis of CVD. Fifty-one percent of the subjects were treated at WH and forty-nine percent at OH. Females were more prevalent than males. As well, the most common age group among these subjects was found to be 70 years and older. About 92% in W~H and 80% in OH received brain imaging diagnostic procedures such as CT or MRI. The cerebral infarction was the most common type of CVD when compared by the kind of utilized hospitals, sex, age group except patient Group who was treated at WH and whose age was lower than 50 years old. The cerebral hemorrhage was more frequent than cerebral infarction among this group. The proportion of cerebral hemorrhage was decreasing and that of cerebral infarction was increasing with age. The most common clinical manifestations of undetermined type of CVD was paralysis of lower extremity in WIT and paralysis of upper extremity in OH. In cerebral hemorrhage loss of consciousness in WIT and dysarthria in OH were most frequently manifested, while in the case of cerebral infarction hemiplegia in WIT and dysarthria in OH were the most common complaints. The interval from the onset of disease to admission to the hospital was 5.5 days in WH arid 31.4 days in OH and the difference was statistically significant. Average admission duration of patients at OH was longer than WH, but it was not statistically significant. In conclusion these results suggest that the effort for systematic and efficient management of CVD patients was necessary for close co-operation and role arrangement between WH and OH considering the positive and negative points of western and oriental medicines.

• Pediatric Infection and Vaccine
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• v.24 no.2
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• pp.71-78
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• 2017

Purpose: The aim of this study was to identify the pathogens of blood stream infection (BSI) in children with hemato-oncologic disorders, to analyze susceptibility patterns of microorganisms to guide empirical antimicrobial therapy, and to compare temporal trends of the pathogen and antimicrobial susceptibility with those of previous studies. Methods: We retrospectively analyzed the medical records of children with hemato-oncologic disorders whose blood culture grew pathogens at the Seoul National University Children's Hospital between 2011 and 2015. Results: A total of 167 patients developed 221 episodes of bacteremia. Among 229 pathogens, gram-negative bacteria (GNB) accounted for 69.0% (64.0% in 2002 to 2005, 63.4% in 2006 to 2010); gram-positive bacteria (GPB) accounted for 28.8% (31.3% in 2002 to 2005, 34.6% in 2006 to 2010); and fungus accounted for 2.2%. Among GNB, Klebsiella species (53.2%, 84/158) and Escherichia coli (19.6%, 31/158) were common. Staphylococcus aureus (48.5%, 32/66) and viridans streptococci (21.2%, 14/66) were frequently isolated among GPB. The susceptibilities of oxacillin and vancomycin in GPB were 54.8% and 96.9% (51.5% and 95.5% in 2002 to 2005; 34.1% and 90.5% in 2006 to 2010), respectively, whereas in GNB, the susceptibilities of cefotaxime, piperacillin/tazobactam, and imipenem were 73.2%, 77.2%, and 92.6% (75.9%, 82.8%, and 93.4% in 2002 to 2005; 62.8%, 82.9%, 93.8% and in 2006 to 2010), respectively. There were no significant differences in the proportion of etiologic agents or the antimicrobial susceptibilities between the current study and that of the previous two studies from 2002 to 2010. Overall fatality rate was 13.1%. Conclusions: GNB predominated in BSI among children with hemato-oncologic disorders. The etiology of bacteremia and antimicrobial susceptibility were comparable to those of the previous studies. Thus, piperacillin/tazobactam can be used as the initial empirical antimicrobial agent in febrile neutropenia.

• Journal of Food Hygiene and Safety
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• v.21 no.4
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• pp.213-217
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• 2006

The halophilic bacterium Vibrio vulnificus is known to be a foodborne pathogen that causes septicemia in human. V. vulnificus infection is characterized by the high fatality rates and the primary attack against a person who have underlying diseases such as liver cirrhosis. However, there is no effective treatment for V. vulnificus septicemia except for classical treatments such as antibiotics. Recently, it has been known that lipoprotein (LDL) plays a major role in the protection against infection and inflammation. Consequently in this paper we analyzed the effects of LDL on V. vulnificus septicemia. We purified V. vulnificus cytolysin, a major virulent factor of V. vulnificus infection and measured inhibitory effects of mouse serum, cholesterol, and LDL on its hemolytic activity. Next experiments were performed to investigate whether LDL has a protective role against septicemia induced by V. vulnificus in mice. Intraperitoneal injection of LDL (1mg as protein) into mice 3hr before V. vulnificus $(1\times10^6\;CFU)$ injection, and V. vulnificus -induced lethality was determined. For the determination the relationship between LDL or cholesterol and prognosis, we determined serum levels of cholesterol and lipoprotein from V. vulnificus septicemia patients (n=15) who had visited the Chonbuk National University Hospital in Chonju. V. vulnificus cytolysin -induced hemolysis of mice erythrocytes was completely inhibited by serum, cholesterol, and low-density lipoprotein. V. vulnificus- induced lethality of mice injected with LDL showed only 40% compared to 100% of control. In survival groups (n=4) of V. vulnificus septicemia patients (n=15), their serum LDL and cholesterol revealed normal levels ($153.3{\pm}40.7,\;LDL;\;190.8{\pm}16.3$, Total cholesterol). However, in death groups (n=11) showed very low levels ($35.6{\pm}13.9,\;LDL;\;59.2{\pm}15.1$, Total cholesterol). Our study indicates that cholesterol and LDL are a prognosis indicator of V. vulnificus septicemia as well as an inhibitor of virulent action of V. vulnificus cytolysin. We suggested that the serum levels of cholesterol or LDL would be major index in the treatment and prevention of V. vulnificus septicemia.