• Journal of Chest Surgery
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• v.31 no.8
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• pp.739-748
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• 1998

Background: It has been well documented that transient occlusion of the coronary artery causes myocardial ischemia and finally cell death when ischemia is sustained for more than 20 minutes. Extensive studies have revealed that ischemic myocardium cannot recover without reperfusion by adequate restoration of blood flow, however, reperfusion can cause long-lasting cardiac dysfunction and aggravation of structural damage. The author therefore attempted to examine the effect of postischemic reperfusion on myocardial ultrastructure and to determine the rationales for recanalization therapy to salvage ischemic myocardium. Materials and methods: Young Holstein-Friesian cows(130∼140 Kg body weight; n=40) of both sexes, maintained with nutritionally balanced diet and under constant conditions, were used. The left anterior descending coronary artery(LAD) was occluded by ligation with 4-0 silk snare for 20 minutes and recanalized by release of the ligation under continuous intravenous drip anesthesia with sodium pentobarbital(0.15 mg/Kg/min). Drill biopsies of the risk area (antero-lateral wall) were performed at just on reperfusion(5 minutes), 1-, 2-, 3-, 6-, 12-hours after recanalization, and at 1-hour assist(only with mechanical respiration and fluid replacement) after 12-hour recanalization. The materials were subdivided into subepicardial and subendocardial tissues. Tissue samples were examined with a transmission electron microscope (Philips EM 300) at the accelerating voltage of 60 KeV. Results: After a 20-minute ligation of the LAD, myocytes showed slight to moderate degree of ultrastructural changes including subsarcolemmal bleb formation, loss of nuclear matrix, clumping of chromatin and margination, mitochondrial destruction, and contracture of sarcomeres. However, microvascular structures were relatively well preserved. After 1-hour reperfusion, nuclear and mitochondrial matrices reappeared and intravascular plugging by polymorphonuclear leukocytes or platelets was observed. However, nucleoli and intramitochondrial granules reappeared within 3 hours of reperfusion and a large number of myocytes were recovered progressively within 6 hours of reperfusion. Recovery was apparent in the subepicardial myocytes and there were no distinct changes in the ultrastructure except narrowed lumen of the microvessels in the later period of reperfusion. Conclusions: It is likely that the ischemic myocardium could not be salvaged without adequate restoration of coronary flow and that the microvasculature is more resistant to reversible period of ischemia than subendocardium and subepicardium. Therefore, thrombolysis and/or angioplasty may be a rational method of therapy for coronarogenic myocardial ischemia. However, it may take a relatively longer period of time to recover from ischemic insult and reperfusion injury should be considered.

• Clinical and Experimental Pediatrics
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• v.51 no.4
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• pp.383-390
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• 2008

Purpose : This study was aimed to analyze the clinical characteristics of patients with acute interstitial pneumonia who had presented similar clinical patterns from March to June, 2006 and to describe our experience of treatment and to identify risk factors associated with prognosis. Methods : The clinical characteristics, radiologic and histopathologic findings and response to steroids of 15 patients (non-survival group [n=7] and survival group [control, n=8]) with acute interstitial pneumonia were investigated through the review of medical records. Results : The mean age of the patients was 26 (range: 3-48) months. Cough, cyanosis and fever were frequent symptoms. The most frequent radiologic findings on admission were pneumomediastium and extensive ground glass opacity. Surgical lung biopsy was performed on 8/15 (53.3%) patients and diffuse alveolar damage was found. Mechanical ventilation was applied for 9/15 (60.0%) patients for 40 (range: 1-99) days. Five patients in survival group received steroid treatment and 7 patients in non-survivial group (P=0.20). One patient in survival group received steroid pulse treatment and 4 patients in non-survival group (P=0.12). Seven patients died all of respiratory failure. The survival rate was 53.4%. Conclusion : The patients with acute interstitial pneumonia which occurred on spring 2006 showed high mortality because of rapidly and extensively progressing pulmonary fibrosis and air leakage. Therefore, we should consider surgical lung biopsy and steroid application earlier. We should recognize this acute interstitial pneumonia occurring on spring in domestics and need to investigate the cause and treatment in large scale.

• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.261-265
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• 2010

Lichens, a symbiotic organism of fungi and algae, cause serious damage to national heritages of stone master piece and costly trees for gardening. The present study was conducted to screen effective fungicides against lichen-forming fungi to control the biological agents deteriorating stone heritages and trees. Five commercial fungicides (Fenarimol EC, Etridiazole EC, Iminoctadinetriacetate SL, Difenoconazole+lminocatadinetriacetate ME and Difenoconazole+Azoxystrobin SC) were tested against the lichen-forming fungi (LFF) isolated from seven saxicolous (Caloplaca sp., Ramalina sp., Xanthoparmelia sp., and Xanthoria sp.,) or corticolous (Parmelia sp.,) lichen species. Preliminary screening test showed that no LFF could grow on the MY (malt-yeast extract) agar medium amended with the recommended concentrations of each fungicide. Further screening was conducted at 1%, 10% and 20% of the recommended concentrations of the fungicides. After 7 week incubation at $15^{\circ}C$ in the dark, Difenoconazole+Iminocatadinetriacetate ME and Difenoconazole+Azoxystrobin SC completely inhibited the fungal growth of all the tested LFF, even at 1% of the concentration. Two fungicides of Fenarimol EC and Iminoctadinetriacetate SL exhibited a moderate inhibition activity at the lower concentrations. Etridiazole EC was less effective in the fungal growth inhibition than the other four fungicides. The results suggested that lichens colonizing on precious stone heritages and trees can be eradicated by applying Difenoconazole+Iminocatadinetriacetate ME and Difenoconazole+Azoxystrobin SC even 1% of the recommended concentrations. Selected fungicide application at such a low concentration will facilitate the chemical use to prevent and preserve stone heritages from biological deterioration induced by lichens and the allied microbes.

• Korean journal of applied entomology
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• v.56 no.3
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• pp.301-308
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• 2017

Locusts, Locusta migratoria (Orthoptera: Acrididae) are periodical unpredictable agricultural pests worldwide and cause serious damage to crop production; however, little consideration has been given to the management of this pest. Herein, we constructed a locust-pathogenic fungal library and confirmed that some fungi could be used as resources for locust management. First, the entomopathogenic fungi were collected from sampled soils using a Tenebrio molitor-based baiting system. For the locust assay, a locust colony was obtained from the National Institute of Agricultural Science and Technology. A total of 34 entomopathogenic fungal granules, which were produced by solid cultures, were placed in the plastic insect-rearing boxes (2 g/box) and nymphs of locust were contained in the box. In 3-7 days, mycosis was observed on the membranous cuticles of the head, abdomen, and legs of locusts. In particular, Metarhizium anisopliae, M. lepidiotae, and Clonostachys rogersoniana exhibited high virulence against the locust. Given that the 34 isolates could be used in field applications, their conidial production and stability (thermotolerance) were further characterized. In the thermotolerance assay, Paecilomyces and Purpureocillium isolates had higher thermotolerance than the other isolates. Most of the fungal isolates produced ca. >$1{\times}10^8conidia/g$ on millet grain medium. In a greenhouse trial, the granular application of M. anisopliae isolate on the soil surface resulted in 85.7% control efficacy. This work suggests that entomopathogenic fungi in a granular form can be effectively used to control the migratory locust.

• Journal of Chest Surgery
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• v.32 no.6
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• pp.556-560
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• 1999

Background: The cause of spontaneous pneumothorax is not yet but it is certain that intrathoracic air comes from ruptured bulla. Video-assisted thoracoscopic surgery(VATS) or open thoracotomy is recommended for thoracic incision in recurrent pneumothorax. However, recurrent rate after bullectomy with the VATS is very high compared to mini-thoracotomy, 3% to 20% and below 2%, respectively. Material and Method: This retrospective analysis was performed on 16 re-operated cases among 446 surgically treated pneumothorax of the 737 cases of spontaneous pneumothorax diagnosed at Yongdong Severance Hospital from Nov. 1992 to June 1997. Result: Among the 446 surgically-treated patients in 737 case of spontaneous pneumothorax, 16 patients underwent re-operation, showing a 3.5% re-operation rate. Male-to-female ratio was 15 to 1 and mean age at initial attack was 20.2 years(ranging from 15 to 50). Mean hospital stay was 6.34 days(ranging from 2 to 20 days) and mean chest tube indwelling period was 4.2 days(ranging from 1-10 days). Median follow-up was 46 months(range 10-66 months). Three different surgical methods were applied : video-assisted thoracoscopic surgery(VAST) in 281 cases, of whom 2 underwent local anesthesia; subaxillary mini-thoracotomy in 159 cases and limited lateral thoracotomy in the remaining 6 cases. Three different re-operative surgical methods were applied ; video-assisted thoracoscopic surgery (VAST) in 6 cases, subaxillary mini-thoracotomy in 9 cases, and limited lateral thoracotomy in the remaining 1 case. The underlying etiological factors of the recurrent pneumothorax after bullectomy were o erlooking type(9) and new growing type(7). Mean recurrent period from previous operation was 1 month for overlooking type and 18 months for new growing type. Conclusion: The underlying etiological factors of recurrent pneumothorax lead to re-operation were new-growing and over-looking type. We need additional treatments besides resecting blebs of prevent the recurrence rate and more gentle handling with forceps due to less damage to the pleura.

• The Korean Journal of Air & Space Law and Policy
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• v.31 no.2
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• pp.215-236
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• 2016

This paper is related to a study on safety management of cosmic radiation in the aviation area, and as a comprehensive study encompassing not only aviation crew but also aviation traffic users, presents issues on an exposure to the cosmic radiation which authors predict may be intensified in a time to come. Although the government of the Republic of Korea has recently activated regulations related to the cosmic radiation, the following improvement measures are further urged to be carried out not only as a regulatory improvement for pushing ahead with effectiveness but also as a supplementary tool. Firstly, a dose limit corresponding to the international standard needs to be applied. Since the dose limit imposed by the Korean government is improperly higher than the international dose limit of the cosmic radiation, the present dose limit needs to be re-established in a range of "not exceeding the international recommendation". Secondly, a new methodology is needed such that aviation companies observe a yearly effective dose limit of passengers. A fact that only aviation crew is specified but passengers are excluded in the related regulation is based on a recommendation presented by the International Commission on Radiological Protection (ICRP). According to the recommendation, Korean government excluded passengers in the "Cosmic Radiation Safety Requirements for Crew". Among the present aviation regulations, there exists a protection standard for protecting aviation traffic users. However, it presents a damage protection only for ticket-related issues. Since this regulatory weakness provides a cause of endangering national health, the authors believe that an improvement in the regulation is needed without sticking to the recommendation from the ICRP. To this end, new regulations are strongly demanded from aspects of not only legal but also regulatory areas. The dose limit in accordance with the international standard is established. However, at least a minute amount of cosmic radiation is continuously acting on all people of Korea. Since more and higher level of cosmic ration may exist in the aviation space, an improved method of representing the minute amount of cosmic radiation in figures. As a result, a desirable regulation may be established for protecting not only crew but also aviation traffic users from being exposed to the cosmic radiation via a legislation of the desirable regulation.

• Journal of agricultural medicine and community health
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• v.34 no.1
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• pp.58-66
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• 2009

Objectives: Active participation of poultry breeder in surveillance system of Avian Influenza (AI) is very important. Therefore this study was conducted to present basis data for active report of AI that is affected by media's coverage in poultry breeder. Methods: Subjects were 88 persons, 28 who were poultry breeder at epidemic area of AI and 60 who were general person at non-epidemic area. Data were collected by the trained investigator from Jul. 1 to Aug. 31, 2008. Respondents were interviewed by means of a structured questionnaire. Results: The third-person effect among perceptions of influence in media's report on the AI was higher in breeder (32.1%) than in non-breeder (10.0%). However, Confidence to media report on the AI was lower in breeder than in non-breeder. Intention to report of the AI was 71.4% in breeder respectively, was 90.0% in non-breeder. There was statistically significant lower in breeder than non-breeder. The cause of avoidance of report was 'economic damage' for 87.5%, which acocounted for the majority of cases. Confidence to media report on the AI were positively correlated with concern on the AI and perception on seriousness of the AI, but negatively correlated with the third-person effect. Conclusions: These results showed that intention to report of the AI of breeder was susceptible to influenced by the third person effect and confidence in media's report on the AI. Therefore we should give a special attention to increase active report of poultry breeder during epidemic period of AI which is consideration of reasonable strategy of media's coverage, including mind and emotion state of poultry breeder.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.462-474
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• 1994

Background : In acute lung injury, activated neutrophils play an important role in tissue damage. For neutrophils to participate in lung inflammation, chemotactic factors released from mononuclear phagocytes are needed to bring these cells to the local site of inflammation, with interleukin-8 (IL-8) being one of the most specific and important chemotactic factors for neutrophils. IL-8 also induces the expression of adhesion molecules and activates neutrophils to release various inflammatory mediators. Lipopolysaccharide(LPS) is one of the most important causes of adult respiratory distress syndrome and can cause release of many inflammatory cytokines including IL-8 leading to acute lung injury. But little is known about the regulatory mechanism of LPS-induced IL-8 gene expression in mononuclear phagocytes. Method : Human alveolar macrophages(HAM) and peripleral blood monocytes(PBMC) were isolated from healthy volunteers. Time and dose relationship of LPS-induced IL-8 mRNA expression was observed by Northern blot analysis. To evaluate the regulatory mechanism of LPS-induced IL-8 gene expression, pretreatment of actinomycin D(AD, $5{\mu}g/ml$) and cycloheximide(CHX, $5{\mu}g/ml$) was done and Northern blot analysis for IL-8 mRNA and ELISA for immunoreactive IL-8 protein in culture supernatant were performed. Results : 1) In HAM, dose and time dependent LPS-induced IL-8 mRNA expression was observed with peak mRNA level at 8 hours post-stimulation. 2) In PBMC, dose and time dependent LPS-induced IL-8 mRNA expression was also observed with peak mRNA level at 4 hours post-stimulation. 3) AD decreased expression of LPS-induced IL-8 gene expression at both mRNAand protein levels in both types of cells. 4) CHX decreased expression of LPS-induced IL-8 gene expression at protein level in both cell types but in HAM, superinduction of IL-8 mRNA was observed while decreased expression of IL-8 mRNA was observed in PBMC. Conclusion : Time and dose dependent LPS-induced IL-8 gene expression was observed in mononuclear phagocytes which is at least partly regulated pretranslationally. LPS-induced IL-8 mRNA expression in HAM needs no de novo protein synthesis and may be under the control of a labile repressor protein while de novo protein synthesis may be needed in PBMC.

• Childhood Kidney Diseases
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• v.6 no.2
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• pp.155-168
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• 2002

Purpose; Systemic lupus erythematosus(SLE) is an autoimmune disease with multi-system involvement and renal damage is a major cause of morbidity and mortality in children. Renal involvement is more common and severe in children than in adults. Therefore, renal biopsy plays a crucial role in planning effective therapy. In this study, we investigated the clinical and pathological findings of lupus nephritis in children to aid clinical care of the disease. Methods: The clinical and pathological data of 40 patients who were diagnosed as SLE with renal involvement in Shinchon Severance Hospital from Jan. 1990 to Sep. 2002 were analyzed retrospectively. Results: The ratio of male to female patients was 1:3 and the median age at diagnosis was 12.1(2-18) years old. FANA(95.0%), anti-ds DNA antibody(87.5%), malar rash(80.0%) were the most common findings among the classification criteria by ARA. Microscopic hematuria with proteinuria(75.0%), nephrotic syndrome(55.0%), and microscopic hematuria alone(15.0%) were the most common renal presentations in the respective order at diagnosis. There were 27 cases with WHO class IV lupus nephritis confirmed by renal biopsy and 3 cases with pathological changes of WHO class type. Different treatment modalities were carried out : prednisolone only in 5 cases, prednisol-one+azat-hioprine in 9 cases, prednisolone+azathioprine+intravenous cyclophosphamide in 14 cases, prednisolone+cyclosporine A+intravenous cyclophosphamide in 12 cases, plasma exchange in 9 cases and intravenous gamma-globulin in 2 cases. The average follow-up period was $51.8{\pm}40.5$ months. During $51.8{\pm}40.5$ months. During follow-up, 4 patients expired. The risk factors associated with mortality were male, WHO class IV and acute renal failure at diagnosis. Conclusion: Renal involvement was noted in 63.5% of childhood SLE, and 67.5% of renal lesion was WHO class IV lupus nephritis which is known to be associated with a poor prognosis. Therefore aggressive treatment employing immunosuppressant during the early stages of disease could be helpful in improving long-term prognosis. But careful attention should be given to optimize the treatment due to unique problems associated with growth, psychosocial development and gonadal toxicity, especially in children.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.11 no.2
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• pp.116-121
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• 2008

Purpose: Cricopharyngeal incoordination is a rare cause of swallowing difficulties in newborns and infants; it is characterized by delayed pharyngeal contractions related to cricopharyngeal relaxation. Dysphagia and repeated aspiration are common findings despite normal sucking. We conducted this study to assess the clinical features of cricopharyngeal incoordination in newborns and infants. Methods: An analysis of the clinical data from 17 patients with cricopharyngeal incoordination who were admitted to the Department of Pediatrics, Pusan National University Hospital, between 2000 and 2006 was conducted retrospectively. The diagnosis of cricopharyngeal incoordination was established by the clinical characteristics and the videofluoroscopic swallowing studies. Results: The male to female ratio was 1:1.1 (males 8, females 9) the age range 1 to 60 days. The body weight of 11 patients (64.7%) was less than the $10^{th}$ percentile at diagnosis. Six patients (35.3%) were born prematurely. The associated anomalies or diseases were chromosomal anomaly (2 cases), congenital heart disease (3 cases), and laryngomalacia, hypoxic brain damage or neonatal seizures (1 case each). The chief complaints of patients were recurrent aspiration pneumonia (10 cases), feeding difficulty (9 cases), dyspnea (4 cases), and chocking (4 cases). The severity of aspiration on the videoesophagogram or esophagogram was mild in 12 cases. The correlation between the severity of aspiration and the duration of tube feeding after the diagnosis was significant (p<0.05). Conclusion: Cricopharyngeal incoordination should be considered in the differential diagnosis of newborns and infants, without known risk factors associated with swallowing dysfunction, when they present with unexplained respiratory problems. Although the prognosis of cricopharyngeal incoordination is good, early diagnosis and tube feeding are recommended to prevent the complications associated with this disorder.