• Journal of Plant Biology
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• v.9 no.1_2
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• pp.7-16
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• 1966

In order to determine the factors related to site quality, 13 areas of Larch growing in the Kwangung and its vicinity forest as sample plots, were examined. Sample plots included various site classes as well as age classes. Three were divided into two groups (major and minor trees). Average height of dominant trees was determined through messurement of 5 to 6 dominant tree in each sample plots. Average height of dominant 30 year-old trees was the basis for site index. A Standard Yield Table for the larch produced in Kwangnung forest was made by various data, which included age class 5, ranging from 10 to 45 years. The relationship of the height of the trees, the site conditions, and ground vegetation are investigated in this paper. The site indexes of 40 forest class age in 28-B and 28-G forest classes of the larch associations for ground vegetation had comparatively rarge differences due to the sampled areas. The relation of the direction of forest communities to the height and the diameter of the tree shwoed that its communiteis of northest and northwest parts appeared higher valueof the height and the diameter. The diameter and the height of trees were closely realted to each other. The samller the occupied area per tree and the smaller the average distance among trees, the more density was increased. The larger the density was the lower height of the trees. In the ground vegetation of the larch communities, there seems to be a definite correlation between the height of trees and the occupied area per tree or the average distance among the trees. The height of trees and site index of two larch communities were as follow: 28-B forest class site index 20.8, height 24.0m, 28-G forest class site index 18.4, height 20.9m. The ground layer was analyzed by the method of Quadrat(20/20sq. cm) with an interval of 1M. It set up 40 Quadrats of the larch communiteis. The community structure of the ground vegetation of two larch was analyzed, and important value was calculated and then evaluated. The ground vegetation under the larch had developed Burmannii Beauv stratal society below the 28-B and 28-G the forest class. Accordingly, the first important value of Burmannii Beauv was found in two ground vegetation below the larch. Therefore, this species could be quantitatively considered as the forest indicator species. Common species of each community appeared 18 species out of 34 species in the ground vegetation under two larch communities. The ground vegetation of the 28-B forest class showed more than that of the 28-G forest class. the similarity of the ground vegetation was measrued by the Frequency Index Community Coefficient. The differences between the associations were lcearly manifested by the ground vegetation tested by Gleason's Frequency Index of Community Coefficient for the analysis of each stratal society of all associations. According to F.I.C.C. the ground vegetation under two larch(28-B and 28-G) forest classes showed higher value. An investigation into the relationship of physical and chemical properties of soil and site was considered the next step to be taken in the study of the larch site classification.

• Advances in pediatric surgery
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• v.2 no.1
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• pp.33-41
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• 1996

This report present the result of the national survey of pediatric surgeons' preferences on diagnosis and treatment of Hirschsprung's disease(HD) carried out in 1993. The questionnaires were sent to twenty-seven members of the Korean Association of Pediatric Surgeons (KAPS) working in twenty-four institutions. The questionnaires were designed to determine the individual surgeon's preference for the methods of diagnosis and treatment of the disease. Twenty-three pediatric surgeons from twenty institutions returned completed forms. The total number of patients diagnosed with HD in 1992 was 190 in this group. The estimated incidence of HD was 1/3,900. The most important symptom was delayed meconium passing and the most preferred diagnostic procedure was barium study. Anorectal manometric examination was carried out by 13 pediatric surgeons and 19 confirmed the diagnosis before operation by rectal biopsy, 12 with full-thickness biopsy and 7 with suction. Frozen section biopsy during operation was done by 22 surgeons. Eight surgeons did one stage operation if the age of the patient is suitable. Definitive operation was usually done at the age of 6 to 11 months. The most preferred operation was Duhamel procedure done by 19. Enterocolitis was the most serious complication of HD. Most of patients had normal continence within 6 to 12 months after operation. The follow-up period was less than 6 years in 16 surgeons. The results were presented at the 9th annual meeting of KAPS in June of 1993. This is the first national survey of HD and it can provide guidelines of diagnosis and treatment of Hirschprung's disease even though it is not a detailed study of patient data.

• Clinical Psychopharmacology and Neuroscience
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• v.16 no.4
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• pp.398-406
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• 2018

Objective: Hospitalization of patients with delirium after visiting the emergency department (ED) is often required. However, the readmission risk after discharge from the ED should also be considered. This study aimed to explore whether (i) immediate hospitalization influences the readmission risk of patients with delirium; (ii) the readmission risk is affected by various risk factors; and (iii) the healthcare cost differs between groups within 28 days of the first ED visit. Methods: Using the National Health Insurance Research Database, the data of 2,780 subjects presenting with delirium at an ED visit from 2000 to 2008 were examined. The readmission risks of the groups of patients (i.e., patients who were and were not admitted within 24 hours of an ED visit) within 28 days were compared, and the effects of the severities of different comorbidities (using Charlson's comorbidity index, CCI), age, gender, diagnosis and differences in medical healthcare cost were analyzed. Results: Patients without immediate hospitalization had a higher risk of readmission within 3, 7, 14, or 28 days of discharge from the ED, especially subjects with more severe comorbidities ($CCI{\geq}3$) or older patients (${\geq}65years$). Subjects with more severe comorbidities or older subjects who were not admitted immediately also incurred a greater healthcare cost for re-hospitalization within the 28-day follow-up period. Conclusion: Patients with delirium with a higher CCI or of a greater age should be carefully considered for immediate hospitalization from ED for further examination in order to reduce the risk of re-hospitalization and cost of healthcare.

• Clinical and Molecular Hepatology
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• v.24 no.4
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• pp.374-383
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• 2018

Background/Aims: There have been numerous efforts to reduce mother-to-child transmission (MTCT) of hepatitis B virus (HBV) with antiviral agents during pregnancy. However, there are limited data regarding the outcomes of pregnant women after delivery. This study was performed to evaluate the efficacy of antiviral agents in preventing MTCT of HBV and maternal long-term outcomes. Methods: The HBV-infected pregnant women treated with antiviral agents to prevent MTCT were retrospectively reviewed. Forty-one pregnant women who received telbivudine or tenofovir during late pregnancy (28-34 week) were analyzed. Hepatitis B virus surface antibody (HBsAb) positivity was tested in 43 infants after 7 months of birth. Eleven mothers were followed >1 year after delivery. Results: The mean HBV DNA titer before antiviral therapy was 8.67 (6.60-9.49) log copies/mL, and the median age at delivery was 32 years (range, 22-40). Eleven patients were treated with tenofovir and 30 with telbivudine. The median duration was 57 days (range, 23-100), and the median HBV DNA titer at birth was 5.06 log copies/mL (range, 2.06-6.50). Antiviral treatments were associated with significant HBV DNA reduction (P<0.001). Among 43 infants (two cases of twins), HBsAb was not detected in two, subsequently confirmed to have HBV infection. Biochemical flare was observed in two of 11 mothers followed >12 months, and an antiviral agent was administered. Conclusions: Antiviral treatment during late pregnancy effectively reduced MTCT. Long-term follow-up should be required in such cases. In addition, given that maternal biochemical flare occurred in 18% of mothers, re-administration of antiviral agents might be required.

• Journal of Korean Neurosurgical Society
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• v.64 no.4
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• pp.592-607
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• 2021

Objective : Few studies exist on primary spinal cord tumors (PSCTs) in pediatric patients. The purpose of this study was to perform descriptive analysis and detailed survival analysis for PSCTs. Methods : Between 1985 and 2017, 126 pediatric patients (male : female, 56 : 70) with PSCTs underwent surgery in a single institution. We retrospectively analyzed data regarding demographics, tumor characteristics, outcomes, and survival statistics. Subgroup analysis was performed for the intramedullary (IM) tumors and extradural (ED) tumors separately. Results : The mean age of the participants was 6.4±5.04 years, and the mean follow-up time was 69.5±46.30 months. The most common compartment was the ED compartment (n=57, 45.2%), followed by the IM (n=43, 34.1%) and intradural extramedullary (IDEM; n=16, 12.7%) compartments. Approximately half of PSCTs were malignant (n=69, 54.8%). The most common pathologies were schwannomas (n=14) and neuroblastomas (n=14). Twenty-two patients (17.5%) died from the disease, with a mean disease duration of 15.8±15.85 months. Thirty-six patients (28.6%) suffered from progression, with a mean period of 22.6±30.81 months. The 10-year overall survival (OS) rates and progression-free survival (PFS) rates were 81% and 66%, respectively. Regarding IM tumors, the 10-year OS rates and PFS rates were 79% and 57%, respectively. In ED tumors, the 10-year OS rates and PFS rates were 80% and 81%, respectively. Pathology and the extent of resection showed beneficial effects on OS for total PSCTs, IM tumors, and ED tumors. PFS was affected by both the extent of removal and pathology in total PSCTs and ED tumors; however, pathology was a main determinant of PFS rather than the extent of removal in IM tumors. The degree of improvement in the modified McCormick scale showed a trend towards improvement in patients with IM tumors who achieved gross total removal (p=0.447). Conclusion : Approximately half of PSCTs were malignant, and ED tumors were most common. The most common pathologies were schwannomas and neuroblastomas. Both the pathology and extent of resection had a decisive effect on OS. For IM tumors, pathology was a main determinant of PFS rather than the extent of removal. Radical excision of IM tumors could be a viable option for better survival without an increased risk of worse functional outcomes.

• Korean Journal of Radiology
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• v.22 no.3
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• pp.324-333
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• 2021

Objective: The clinical course of an individual patient with heart failure is unpredictable with left ventricle ejection fraction (LVEF) only. We aimed to evaluate the prognostic value of cardiac magnetic resonance (CMR)-derived myocardial fibrosis extent and to determine the cutoff value for event-free survival in patients with non-ischemic cardiomyopathy (NICM) who had severely reduced LVEF. Materials and Methods: Our prospective cohort study included 78 NICM patients with significantly reduced LV systolic function (LVEF < 35%). CMR images were analyzed for the presence and extent of late gadolinium enhancement (LGE). The primary outcome was major adverse cardiac events (MACEs), defined as a composite of cardiac death, heart transplantation, implantable cardioverter-defibrillator discharge for major arrhythmia, and hospitalization for congestive heart failure within 5 years after enrollment. Results: A total of 80.8% (n = 63) of enrolled patients had LGE, with the median LVEF of 25.4% (19.8-32.4%). The extent of myocardial scarring was significantly higher in patients who experienced MACE than in those without any cardiac events (22.0 [5.5-46.1] %LV vs. 6.7 [0-17.1] %LV, respectively, p = 0.008). During follow-up, 51.4% of patients with LGE ≥ 12.0 %LV experienced MACE, along with 20.9% of those with LGE ≤ 12.0 %LV (log-rank p = 0.001). According to multivariate analysis, LGE extent more than 12.0 %LV was independently associated with MACE (adjusted hazard ratio, 6.71; 95% confidence interval, 2.54-17.74; p < 0.001). Conclusion: In NICM patients with significantly reduced LV systolic function, the extent of LGE is a strong predictor for long-term adverse cardiac outcomes. Event-free survival was well discriminated with an LGE cutoff value of 12.0 %LV in these patients.

• Korean Journal of Radiology
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• v.23 no.2
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• pp.172-179
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• 2022

Objective: We aimed to evaluate the ostium of right coronary artery of anomalous origin from the left coronary sinus (AORL) with an interarterial course throughout the cardiac cycle on CT and analyze the clinical significance of the ostial findings. Materials and Methods: From January 2011 to December 2015, 68 patients (41 male, 57.3 ± 12.1 years) with AORL with an interarterial course and retrospective cardiac CT data were included. AORL was classified as high or low ostial location based on the pulmonary annulus in the diastolic and systolic phases on cardiac CT. In addition, the height, width, height/width ratio, area, and angle of the ostium were measured in both cardiac phases. After cardiac CT, patients were followed until December 31, 2020 for major adverse cardiac events (MACE). Clinical and CT characteristics associated with MACE were explored using Cox regression analysis. Results: During a median follow-up period of 2071 days (interquartile range, 1180.5-2747.3 days), 13 patients experienced MACE (19.1%, 13/68). Seven (10.3%, 7/68) had the ostial location change from high in the diastolic phase to low in the systolic phase. In the univariable analysis, younger age (hazard ratio [HR] = 0.918, p < 0.001), high ostial location (HR = 4.008, p = 0.036), larger height/width ratio (HR = 5.621, p = 0.049), and smaller ostial angle (HR = 0.846, p = 0.048) in the systolic phase were significant predictors of MACE. In multivariable cox regression analysis, younger age (adjusted HR = 0.917, p = 0.002) and high ostial location in the systolic phase (adjusted HR = 4.345, p = 0.026) were independent predictors of MACE. Conclusion: The ostial location of AORL with an interarterial course can change during the cardiac cycle, and high ostial location in the systolic phase was an independent predictor of MACE.

• Journal of Chest Surgery
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• v.38 no.5 s.250
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• pp.357-365
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• 2005

Background: Patients with mitral regurgitation (MR) in the setting of coronary artery disease have a dismal long-term prognosis whether treated medically or surgically. Moreover, the optimal management of moderate ischemic MR at the time of coronary artery bypass grafting (CABG) remains the subjects of controversy. Thus, the present retrospective study was undertaken to determine whether mitral valve surgery for moderate ischemic MR at the time of CABG would be preferable to CABG alone in terms of clinical outcome. Material and Method: Between January 1997 and December 2003, 34 patients with moderate (Gr 3/4) ischemic MR underwent CABG alone (Group I, n=23) or CABG plus mitral valve surgery (Group II, n=11). Operative mortality, long-term survival and echocardiographic parameters were used to evaluate the efficacy of mitral valve surgery in patients with moderate ischemic MR. The mean follow-up durations of each group were $69.3\pm4.3$ months and $53.1\pm4.9$ months respectively. Result: There was no hospital mortality in both groups. There was one case of late mortality in Group I. The mean number of bypass graft was similar ($3.8\pm1.2\;vs\;3.7\pm1.3$ respectively). Cardiopulmonary bypass time was longer in group II (p=0.014). In group II, all of the patients received mitral annuloplasty using ring. On immediate postoperative echo-cardiogram, mitral regurgitation was reduced more in group II (p=0.002). Echocardiogram performed at last follow-up state showed no difference except the grade of MR between the two groups. Actuarial survival of both groups at 5 years was similar ($95.5\%\;vs\;100\%$, p=0.48). Conclusion: This study shows that in selected patients with moderate ischemic MR, CABG without mitral valve surgery might be sufficient. However, patients with low EF and NYHA functional class pre-operatively had tendency of significant residual MR, so mitral valve surgery should be necessary in these patients, and moreover, MR severity and left ventricle volume decreased more in mitral valve surgery group. Therefore, more large-scale studies are necessary to determine these effects on the ventricular function and long-term survival.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.9 no.2
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• pp.210-217
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• 2006

Purpose: Crohn disease (CD) in children is frequently complicated by malnutrition and growth retardation. Conventional treatment with corticosteroid may also affect the growth of children, which may be alleviated by nutritional therapy. Therefore, we performed this study to evaluate the role of nutritional therapy in the treatment of CD in children. Methods: The study cohort consisted of thirty children under the age of 17 years, admitted to the Asan Medical Center from 2001 to 2005. While 11 children received nutritional therapy (NT) with an elemental diet, 19 received conventional corticosteroid therapy (ST). Comparative analysis was performed for the rate of the induction of remission, recurrence, disease activity index of pre and post-treatment, and changes of the growth using mean standard deviation score for weight (zW) and height (zH). Results: Ten of 11 children with NT and 18 of 19 children with ST completed the therapy. Two of them were lost to follow-up during the treatment. All 10 children with NT and 15 of 18 children with ST achieved remission. While there was no recurrence in children with NT, 7 with ST showed recurrence within 1 year. Pre- and post treatment Pediatric Crohn disease Activity Index (PCDAI) did not show a difference between the two groups. There were no differences in zW and zH between the two groups after 1 year of follow-up. Conclusion: This study showed that nutritional therapy could be considered instead of steroid therapy for treatment of children with CD. However, a long-term study will be needed to determine the long-term efficacy.

• Tuberculosis and Respiratory Diseases
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• v.50 no.4
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• pp.484-492
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• 2001

Background : Pulmonary tuberculosis with a remaining cavitary lesion is considered to be a problem with the course of treatment. In particular, re-treatment cases tend to respond poorly to current anti-tuberculosis agents. Therefore the factors that are related with the poor closure of a cavitary lesion in pulmonary tuberculosis during treatment were evaluated. Methods : A retrospective review of the medical records and chest X -ray films of 68 patients who had chemotherapy for the pulmonary tuberculosis with cavitary lesions was made. All the patients had been followed up for more than 12 months at National Masan Tuberculosis Hospital as of Aug. 2000. Results : The male to female ratio was 3.9:1.72.4% of the patients were between 20 to 50 years of age. 66.2% of the cavitary lesions on the chest X-ray films were confined to the upper lung fields : 36.8% in the right upper lung field and 29.4% in the left upper lung field. 82.4% of the cavities were less than 40 mm in their size, and 83.8% were less than 6 mm thick. The cavitary lesions were closed in 48 cases and remained in 20 cases during a follow-up period of more than 12 months. The factors that are thought to affect to the outcomes of the cavities were age, past medication history, the number of unused drugs, and the number of sensitive drugs. Conclusion : In the treatment courses of pulmonary tuberculosis with cavitary lesions, the following factors are associated with less desirable outcome:an age over 45, a past medication history of more than 2 courses of treatment, The number of unused drugs not exceeding average 6 and the number of sensitive drugs not exceeding average 7.