• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.27 no.4
• /
• pp.371-384
• /
• 1982

Highly cold tolerant varieties are requested not only at high latitute cool area but also tropical high elevated areas, and the required tolerance is different from location to location. IRRI identified 6 different types of cold tolerance required in the world for breeding purpose; a) Hokkaido type, b) Suweon type, c) Taipei 1st season type, d) Taipei 2nd season type, e) Tropical alpine type and, f) Bangladesh type. The cold tolerance requested in Korea is more eargent in Tongil group cultivars and their required tolerance is the one such as the physiological activities at low temperature are as active as in Japonica group cultivars at least during young seedling stage and reproduction stage. With conventional Japonica cultivars, such cold tolerant characters are requested as short growth duration but stable basic vegetative growth, less sensitive to high temperature and less prolonged growth duration at low temperature. The methods screening for cold tolerance were developed rapidly after the Tongil cultivar was reliesed. The facilities of screening for cold tolerance, such as, low temperature incubator, cold water tank, growth cabinet, phytotron, cold water nursery in Chuncheon, breeding nursery located in Jinbu, Unbong and Youngduk, are well established. Foreign facilities such as, cold water tank with the rapid generation advancement facilities, cold nurseries located in Banaue, Kathmandu and Kashimir may be available for the screening of some limitted breeding materials. For the reference, screening methods applied at different growth stages in Japan are introduced. The component characters of cold tolerance are not well identified, but the varietal differences in a) germinability, b) young seedling growth, c) rooting, d) tillering, e) discolation, f) nutrition uptake, g) photosynthesis rate, h) delay in heading, i) pollen sterility, and j) grain fertility at low temperature are reported to be distinguishable. Relationships among those traits are not consistent. Reported studies on the inheritance of cold tolerance are summarized. Four or more genes are controlling low temperature germinability, one or several genes are controlling seedling tolerance, and four or more genes are responsible for the pollen fertility of the rice treated with cold air or grown in the cold water nursery. But most of those data indicate that the results may come out in different way if those were tested at different temperature. Many cold tolerant parents among Japonicas, Indicas and Javanicas were identified as the results of the improvement of cold tolerance screening techniques and IRTP efforts and they are ready to be utilized. Considering a) diversification of germ plasm, b) integration of resistances to diseases and insects, c) identification of adaptability of recommending cultivars and, d) systematic control of recommending cultivars, breeding strategies for short term and long term are suggested. For short term, efforts will be concentrated mainly to the conventional cultivar group. Domestic cultivars will be used as foundation stock and ecologically different foreign introductions such as from Hokkaido, China or from Taiwan, will be used as cross parents for the adjustment of growth durations and synthsize the prototype of tolerances. While at the other side, extreme early waxy Japonicas will be crossed with the Indica parents which are identified for their resistances to the diseases and insects. Through the back corsses to waxy Japonicas, those Indica resistances will be transfered to the Japonicas and these will be utilized to the crosses for the improvement of resistances of prototype. For the long term, efforts will be payed to synthsize all the available tolerances identified any from Japonicas, Indicas and Javanicas to diversify the germ plasm. The tolerant cultivars newly synthsized, should be stable and affected minimum. to the low temperature at all the growing stages. The resistances to the diseases and insects should be integrated also. The rapid generation advancement, pollen culture and international cooperations were emphasized to maximize the breeding efficiency.

• Journal of the Mineralogical Society of Korea
• /
• v.21 no.3
• /
• pp.227-237
• /
• 2008

Arsenic has recently become of the most serious environmental concerns, and the worldwide regulation of arsenic fur drinking water has been reinforced. Arsenic contaminated groundwater and soil have been frequently revealed as well, and arsenic contamination and its treatment and measures have been domestically raised as one of the most important environmental issues. Arsenic behavior in geo-environment is principally affected by oxides and clay minerals, and particularly iron (oxy)hydroxides have been well known to be most effective in controlling arsenic. Among a number of iron (oxy)hydroxides, for this reason, 2-line ferrihydrite was selected in this study to investigate its effect on arsenic behavior. Adsorption of 2-line ferrihydrite was characterized and compared between As(III) and As(V) which are known to be the most ubiquitous species among arsenic forms in natural environment. Two-line ferrihydrite synthesized in the lab as the adsorbent of arsenic had $10\sim200$ nm for diameter, $247m^{2}/g$ for specific surface area, and 8.2 for pH of zero charge, and those representative properties of 2-line ferrihydrite appeared to be greatly suitable to be used as adsorbent of arsenic. The experimental results on equilibrium adsorption indicate that As(III) showed much stronger adsorption affinity onto 2-line ferrihydrite than As(V). In addition, the maximum adsorptions of As(III) and As(V) were observed at pH 7.0 and 2.0, respectively. In particular, the adsorption of As(III) did not show any difference between pH conditions, except for pH 12.2. On the contrary, the As(V) adsorption was remarkably decreased with increase in pH. The results obtained from the detailed experiments investigating pH effect on arsenic adsorption show that As(III) adsorption increased up to pH 8.0 and dramatically decreased above pH 9.2. In case of As(V), its adsorption steadily decreased with increase in pH. The reason the adsorption characteristics became totally different depending on arsenic species is attributed to the fact that chemical speciation of arsenic and surface charge of 2-line ferrihydrite are significantly affected by pH, and it is speculated that those composite phenomena cause the difference in adsorption between As(III) and As(V). From the view point of adsorption kinetics, adsorption of arsenic species onto 2-line ferrihydrite was investigated to be mostly completed within the duration of 2 hours. Among the kinetic models proposed so for, power function and elovich model were evaluated to be the most suitable ones which can simulate adsorption kinetics of two kinds of arsenic species onto 2-line ferrihydrite.

• The Korean Journal of Nuclear Medicine
• /
• v.39 no.4
• /
• pp.252-256
• /
• 2005

Purpose: Thyroglobulin (Tg) is a valuable and sensitive tool as a marker for diagnosis and follow-up for several thyroid disorders, especially, in the follow-up of patients with differentiated thyroid cancer (DTC). Often, clinical decisions rely entirely on the serum Tg concentration. But the Tg assay is one of the most challenging laboratory measurements to perform accurately owing to antithyroglobulin antibody (Anti-Tg). In this study, we have compared the degree of Anti-Tg effects on the measurement of Tg between availale Tg measuring kits. Materials and Methods: Measurement of Tg levels for standard Tg solution was performed with two different kits commercially available (A/B kits) using immunoradiometric assay technique either with absence or presence of three different concentrations of Anti-Tg. Measurement of Tg for patient's serum was also performed with the same kits. Patient's serum samples were prepared with mixtures of a serum containing high Tg levels and a serum containg high Anti-Tg concentrations. Results: In the measurements of standard Tg solution, presence of Anti-Tg resulted in falsely lower Tg level by both A and B kits. Degree of Tg underestimation by h kit was more prominent than B kit. The degree of underestimation by B kit was trivial therefore clinically insignificant, but statistically significant. Addition of Anti-Tg to patient serum resulted in falsely lower Tg levels with only A kit. Conclusion: Tg level could be underestimated in the presence of anti-Tg. Anti-Tg effect on Tg measurement was variable according to assay kit used. Therefore, accuracy test must be performed for individual Tg-assay kit.

• Tuberculosis and Respiratory Diseases
• /
• v.45 no.3
• /
• pp.509-518
• /
• 1998

Background: Short-course chemotherapy for 6 months is well established for pulmonary tuberculosis. However, little is known about the efficacy of the short-course chemotherapy for tuberculous pleural effusion. Tuberculous pleural effusion itself may be self-limiting without any treatment, but about two thirds of the patients with tuberculous pleural effusion may subsequently develop pulmonary tuberculosis within 5 years. After completing treatment for tuberculous pleural effusion. prolonged follow-up is necessary for evaluating the efficacy of the treatment There is still no report on the efficacy of 6-month regimens for tuberculous pleural effusion in Korea, where the incidence of tuberculous disease and drug resistance is high. We studied the efficacy of 6 month short-course chemotherapy comparing with 9 month chemotherapy. Method : Retrospective study was done through medical record review in 238 patients with tuberculous pleural effusion who admitted to Asan Medical Center during May 1989-May 1993. The diagnosis of tuberculous pleural effusion was made by bacteriologic or histopathologic study. Results: Among 238 patients, 38 patients were dropped out during follow-up period. In 2 patients, second line drugs were prescribed according to known drug resistance results. And, in 23 patients, treatment longer than 9 months was done due to accompanying extrapulmonary tuberculosis or durg resistance. In 8 patients, treatment regimen was changed due to hepatotoxicity. Remaining 167 cases (70.2%) completed the treatment as scheduled ; 6 month chemotherapy in 88 cases and 9 month chemotherapy in 79 cases. In 60 patients (35.9%) with pleural effusion only in chest X-ray finding, sputum smear or culture for M.tuberculosis was positive in 6 cases (10.0%), and in 63 patients (37.7%) with radiologically inactive pulmonary tuberculosis, sputum smear or culture was positive in 18 cases (28.6%). In 44 patients (26.3%) with radiologically active pulmonary tuberculosis, the sputum smear or culture was positive in 24 cases (54.5%). In 6-month chemotherapy group (n=88), during mean 23 months (range; 1~61months) follow-up period, pulmonary tuberculosis developed in 1 case (1.4%). In 9-month chemotherapy group(n=79), during mean 23 months (range; 3~70months) follow-up period, pulmonary tuberculosis developed in 2 cases (2.5%). All the cases who developed pulmonary tuberculosis also showed active pulmonary tuberculosis on initial chest X-ray before treatment Conclusion: In patients with tuberculous pleural effusion, the incidence of pulmonary tuberculosis after 6 month chemotherapy showed no difference from that after 9 month chemotherapy. Thus, 6 month short-course chemotherapy seems to be an effective treatment for tuberculous pleural effusion.

• Tuberculosis and Respiratory Diseases
• /
• v.51 no.3
• /
• pp.248-259
• /
• 2001

Background : In diagnosis or monitor of the airway obstruction in bronchial asthma, the measurement of $FEV_1$ in the standard method because of its reproducibility and accuracy. But the measurement of peak expiratory flow(PEF) by peak flow meter is much simpler and easier than that of $FEV_1$ especially in children. Yet there have been still no data of the predicted normal values of PEF measured by peak flow meter in Korean children. This study was conducted to provide equations to predict the normal value of PEF and correlation between PEF and $FEV_1$ in healthy children. Method : PEF was measured by MiniWright peak flow meter, and the forced expiratory volume and the maximum expiratory flow volume curves were measured by Microspiro HI 501(Chest Co.) in 346 healthy children(age:5-16 years, 194 boys and 152 girls) without any respiratory symptoms during 2 weeks before the study. The regression equations for various ventilatory parameters according to age and/or height, and the regression equations of $FEV_1$ by PEF were derived. Results : 1. The regression equation for PEF(L/min) was: $12.6{\times}$age(year)+$3.4{\times}$height(cm)-263($R^2=0.85$) in boys, and $6{\times}$age(year)+$3.9{\times}$height(cm)-293($R^2=0.82$) in girls. 2. The value of FEFmax(L/sec) derived from the maximum expiratory flow volume curves was multiplied by 60 to compare with PEF(L/min), and PEF was faster by 125 L/min in boys and 118 L/min in girls, respectively. 3. The regression equation for $FEV_1$(ml) by PEF(L/min) was:$7{\times}$PEF-550($R^2=0.82$) in boys, and $5.8{\times}$PEF-146 ($R^2=0.81$) in girls, respectively. Conclusion : This study provides regression equations predicting the normal values of PEF by age and/or height in children. And the equations for $FEV_1$, a gold standard of ventilatory function, was predicted by PEF. So, in taking care of children with airway obstruction, PEF measured by the peak flow meter can provide useful information.

• Journal of Nutrition and Health
• /
• v.45 no.6
• /
• pp.562-576
• /
• 2012

Han-sik is a term in Korean that may indicate any Korean dish or food. At present, there is no general consensus on the definition of Han-sik among scholars or professionals in related fields. The aim of this study was to investigate perceptions of Han-sik by professionals in the fields of food, nutrition, and culinary arts using 512 dishes and foods commonly consumed by Koreans using the 4th Korean National Health and Nutrition Survey. A total of 117 professionals out of 185 initially contacted professionals participated in this online survey. We calculated the rate of respondents with a positive answer, that is "It is Han-sik', on each dish and food from the 512 items in 28 dish groups. Items were categorized into five groups according to their Han-sik perception rate: over 90%, 75-89%, 50-74%, 25-49%, and below 25%. Most items in the three dish groups 'Seasoned vegetables, cooked (Namul Suk-chae)', 'Kimchis', and 'Salt-fermented foods (Jeotgal)' showed high perception rates of Han-sik, with a higher than 90% positive response. Items in 'Soups', 'Stews', and 'Steamed foods' dish groups also showed high perception rates of Han-sik. However, no item showed a greater than 90% Han-sik perception rate in 'Fried foods (Twigim)', 'Meat, poultry and fishes', 'Legumes, nuts, and seeds', 'Milk and milk products', 'Sugars and confectioneries', and 'Soup'. Most items in the 'Milk and milk products', 'Sugars and confectioneries', and 'Soup' groups belonged to the lowest perception rate of below 25%. There was a significant difference in the proportion of items perceived as Han-sik by the length of living abroad to (p < 0.05). In summary, the perception rate of Han-sik seemed to be affected by the cooking method, ingredients, and length of time living abroad by the professionals. Further studies targeting subjects with different characteristics and socioeconomic status are warranted to define the concept of Han-sik.

• Korean Journal of Poultry Science
• /
• v.35 no.3
• /
• pp.291-302
• /
• 2008

To acquire essentially necessary basic data to establish feeding system by verifying appropriate dietary energy and protein level for the growth of commercial slow growing broiler chicks within the country, two experiments were conducted for 5 weeks. One day old, 1,404 male and female broiler chicks were used for the experiments, and 26 chicks were placed at each pen. The energy level of feed was maintained about 3,000 or 3,100 kg/kcal for whole breeding period of 5 weeks, and protein content was adjusted about 20, 21, and 22% during the first two weeks and the content was adjusted to 18, 19, 20, 21, and 22% from the 3 to 5 weeks old of the experiment. The categories of body weight and feed intake amount were monitored to calculate the productivity and blood sampling was conducted for the analysis at the end of each experiment. Experiment 1:Although the productivity by the ME content difference during $0{\sim}2$ weeks did not have significant difference and the body weight increase by the difference of CP content and feed intake amount did not have much difference, the feed requirement rate was statistically improved in CP 21 and 22% treatment groups compared to the CP 20% group (P<0.05). The feed ME 3,100 kcal/kg treated group during $3{\sim}5$ weeks after starting the experiment revealed to show improved feed requirement rate (P<0.05). Within the period of experiment, the CP 22% treated group resulted to show significant body weight increase compared to the groups treated with low levels of CP (P<0.05) and the feed requirement rate was improved in high CP treated group compared to low CP treated groups, but the feed intake amount did not show significant difference between treated groups. During the experiment period, the body weight increase and feed requirement rate revealed to interact between ME and CP (P<0.05). During the whole experiment period of the 5 weeks, the feed requirement rate was improved in ME 3,100 kcal/kg treated group than the groups treated with ME 3,000 kcal/kg, and the CP (20) 18% treatment groups resulted to show higher values than other treatment groups (P<0.05). Body weight increase was high in CP (22) 22% treated groups than those of CP (21) 21% and (20) 18% treated groups, and the interaction between ME and CP was found at body weight increase and feed requirement rate (P<0.05). Although blood albumin and total cholesterol levels were elevated in ME 3,100 kcal/kg treated group than ME 3,000 kcal/kg treated group, but neutral fat content was reduced (P<0.05). On the other hand, the total cholesterol content was increased in CP (22) 21% treated group than CP (22) 20% and CP (20) 18% treated groups (P<0.05). Experiment 2: The body weight increase in 0-2 weeks was higher in ME 3,100 kcal/kg treated group than ME 3,000 kcal/kg treated group, and it was highly improved in CP 22% treated group than CP 20% treated group by showing the interaction between CP and ME (P<0.05). The significant improvement of feed requirement rate was observed in CP 21% and 22% treated groups compared to CP 20% treated group (P<0.05). The productivity between the growth period from 3 to 5 weeks of age and whole growth period resulted to show no significant difference. Although no difference was observed in blood composition between treated groups, the interaction of ME and CP on cholesterol content was accepted at the range of P<0.05). Therefore, it is considered that the appropriate dietary protein level within feed for the physiology of growing broiler chicks was 22% or more for the first two weeks and protein level of 21% or 20% from 3 to 5 weeks old for the maximization of productivity. Even if the energy level within feed had some partial effects on the productivity, but did not show consistency. So, further experiments needto be conducted by differentiating the energy level.

• Childhood Kidney Diseases
• /
• v.9 no.2
• /
• pp.222-230
• /
• 2005

Purpose : ARC syndrome refers to an association of arthrogryposis, renal tubular dysfunction, and cholestasis. The VPS33B gene was recently identified as the causative gene. So far, 41 cases of ARC syndrome have been reported worldwide, and it has rarely been reported in Korea. This study was conducted to report the clinical findings of seven ARC syndrome cases in Korean children, focusing especially on renal tubular dysfunction. Methods : The hospital records of 7 cases diagnosed as ARC syndrome at Severance Hospital between Mar. 1995 and Aug. 2005 were reviewed and analyzed. Results : Of the 7 cases, 4 were boys and 3 were girls. Six patients(85$\%$) were born with normal birth weight at term, and one was born at preterm. All cases presented with cholestasis and severe jaundice. According to the type of arthrogryposis described by Brown et al, type 3 and 4 were found in 2 patients and type,6, 7, and the undistributed type in one patient respectively. Other associated clinical findings were as follows : failure to thrive in 6(85$\%$), lax skin in 5(71$\%$), and gray platelet syndrome in 4(57$\%$). Urine analysis revealed 6 cases(85$\%$) with proteinuria, 3(43$\%$) with hematuria, 5(71$\%$) with glycosuria, 2(29$\%$) with phosphaturia and 2(29$\%$) with calciuria. Serum electrolytes showed 4 cases(57$\%$) with hyponatremia, 3(43$\%$) with hypokalemia, and 1(14$\%$) with creatinine elevation. Renal tubular dysfunctions were diagnosed as renal tubular acidosis in 6 cases(85$\%$), nephrogenic diabetes insipidus in 2(29$\%$), and Fanconi syndrome in 2(29$\%$). During the follow-up period, 2(29$\%$) had no treatment, 5(85$\%$) had continuous supplementation to correct the electrolyte imbalance and acidosis, and 1(14$\%$) had dialysis. Only one patient had a family history of ARE syndrome in a sibling. Four cases(57$\%$) were diagnosed at the mean age of 8.2 months, and one case was lost during follow-up. Ages of the survived 2 cases were 13 and 25 months, respectively. Conclusion : The rare disease of ARC syndrome Is associated with severe renal dysfunction. However, this study revealed that the renal manifestation of ARC syndrome in Korean children is relatively mild and survival rate is higher than that of previous studies. Contrary to previous reports, this study showed that familial cases are rare and sporadic occurence is possible in Korea. Thus, the diagnosis of this syndrome requires a careful evaluation of the venal function in cases of congenital arthrogryposis, and a mandatory genetic counseling of affected family for prevention of familial occurance. (J Korean Soc Pediatr Nephrol 2005;9:222-230)

• Journal of Chest Surgery
• /
• v.41 no.5
• /
• pp.598-604
• /
• 2008

Background: The improvements in endoscopic equipment and surgical robots has encouraged the performance of minimally invasive cardiac operations. Yet only a few Korean studies have compared this procedure with the sternotomy approach. Material and Method: Between December 2005 and July 2007, 48 patients (group A) underwent minimally invasive cardiac surgery with AESOP through a small right thoracotomy. During the same period, 50 patients (group B) underwent conventional surgery. We compared the operative time, the operative results, the post-operative pain and the recovery of both groups. Result: There was no hospital mortality and there were no significant differences in the incidence of operative complications between the two groups. The operative $(292.7{\pm}61.7\;and\;264.0{\pm}47.9min$, respectively; p=0.01) and CPB times ($128.4{\pm}37.6\;and\;101.7{\pm}32.5min$, respectively; <0.01) were longer for group A, whereas there was no difference between the aortic cross clamp times ($82.1{\pm}35.0\;and\;87.8{\pm}113.5min$, respectively; p=0.74) and ventilator times ($18.0{\pm}18.4\;and\;19.7{\pm}9.7$ hr, respectively; p=0.57) between the groups. The stay on the ICU $(53.2{\pm}40.2\;and\;72.8{\pm}42.1hr$, respectively; p=0.02) and the hospitalization time ($9.7{\pm}7.2\;and\;14.8{\pm}11.9days$, respectively; p=0.01) were shorter for group A. The Patients in group B had more transfusions, but the difference was not significant. For the overall operative intervals, which ranged from one to four weeks, the pair score was significantly lower for the patients of group A than for the patients of group B. In terms of the postoperative activities, which were measured by the Duke Activity Scale questionnaire, the functional status score was clearly higher for group A compared to group B. The analysis showed no difference in the severity of either post-repair of mitral ($0.7{\pm}1.0\;and\;0.9{\pm}0.9$, respectively; p=0.60) and tricuspid regurgitation ($1.0{\pm}0.9\;and\;1.1{\pm}1.0$, respectively; p=0.89). In both groups, there were no valve related complications, except for one patient with paravalvular leakage in each group. Conclusion: These results show that compared with the median sternotomy patients, the patients who underwent minimally invasive surgery enjoyed significant postoperative advantages such as less pain, a more rapid return to full activity, improved cosmetics and a reduced hospital stay. The minimally invasive surgery can be done with similar clinical safety compared to the conventional surgery that's done through a median sternotomy.

• Clinical and Experimental Pediatrics
• /
• v.48 no.8
• /
• pp.832-838
• /
• 2005

Purpose : Mycoplasma pneumoniae infection is relatively common in childhood. Its extrapulmonary manifestations have been reported so much, but hepatitis associated with it has been reported rarely in Korea. Methods : A clinical study was performed on 556 patients of M. pneumoniae pneumonia diagnosed serologically at Gil hospital from January 2001 to December 2004. We reviewed 65 cases among these patients, who had elevated level of serum AST and ALT greater than 50 IU/L respectively without evidence of hepatitis A, B, C, Cytomegalovirus and Ebstein-Barr virus infections. Results : Hepatitis occurred in 11.7% of Mycoplasma pneumoniae pneumonia, especially in fall and winter times. Male to female ratio was 1.2 : 1 and the mean age was 4 years and 3 months. Besides hepatitis, cough(95.4%), sputum(52.3%) and dyspnea(12.3%) were common as pulmonary manifestations. And among gastrointestinal manifestations, nausea/vomiting(26.2%) was the most common symptom, followed by poor oral intake(12.3%), diarrhea(12.3%) and abdominal pain(6.2%). In addition to hepatomegaly(4.6%) and splenomegaly(4.6%), coarse breathing sound was the most common physical manifestation, followed by rale(63.1%), pharyngeal injection(26.2%), and rash(10.8%). Anemia was noted in 20.0%, neutrophilia in 10.8%, eosinphilia in 38.5% and thrombocytosis in 6.2%, respectively. Mean level of ESR and CRP was 32.02 mm/hr and 6.69 mg/dL, respectively. Mean level of AST and ALT was 293.80 IU/L and 181.48 IU/L, respectively. Hyperbilirubinemia was noted in 7.7% and hypoalbuminemia was noted in 58.5%. Lobar or lobular pneumonia(78.5%) was the most common finding in chest X-ray and left lower lobe(39.2%) was most commonly affected. Pleural effusion was noted in 26.2%. Mean duration of hospitalization was 9.91 days. Serum AST/ALT level was normalized within 9.94 days and pulmonary consolidation resolved within 14.29 days. Conclusion : The prognosis of M. pneumoniae hepatitis is good. However, liver function should be considerately checked in M. pneumoniae infection because its incidence is not so low.