• Journal of Life Science
• /
• v.17 no.2 s.82
• /
• pp.198-203
• /
• 2007

DNA transfection is a powerful tool for studying gene functions. The $Ca^{2+}$-phosphate precipitation remains one of the most popular and cost-effective transfection techniques. Mature neurons are more resistant to transfection than young ones and most other cell types, and easy to die if microenvironment changes. Here, we report a transfection protocol for mature neurons. The critical modifications are inclusion of glial cells in culture and careful control of $Ca^{2+}$-phosphate precipitation under microscope. Cerebral glial cells were grown until ${\sim}70-80%$ confluence in DMEM/10% horse serum, which was thereafter replaced with serum-free Neurobasal/Ara-C, and 319 hippocampal neurons were plated onto the glial layer Formation of fine $DNA/Ca^{2+}$-phosphate precipitates was induced using Clontech $CalPhos^{TM}$ Mammalian Transfection Kit, and the size ($0.5-1\;{\mu}m$ in diameter) and density(about 10 particles/$100\;{\mu}m^2$) were carefully controlled by the time of incubation in the medium. This modified protocol can be reliably applied for transfection of mature neurons that are maintained longer than two weeks in vitro, resulting in 10-15 healthy transfected neurons per a well of 24-well plates. The efficacy of the protocol was verified by punctate expression of $pEGFP-CaMKII{\alpha}$, a synaptic protein, and diffuse expression of pDsRed2. Our protocol provides a reliable method for transfection of mature neurons in vitro.

• The Journal of Korean Medicine
• /
• v.18 no.1
• /
• pp.480-498
• /
• 1997

This study was to investigate the protective and anticirrhotic effects of Mockhyangjokisan and Haewooljoweetang on the liver cirrhosis or fibrosis induced by prolonged bile duct ligation; a new experimental model for cirrhosis and the intraperitoneal injection of dimethylnitrosamine in the rat. The development of fibrosis or cirrhosis and its inhibition by the two prescriptions were examined by the chemical analysis of AST, ALT, and hydroxyproline. The results obtained were as follows. 1. The increase of serum asparate aminotransferase induced by bile duct ligation was inhibited by the administration of Mockhyangjokisan and Haewooljoweetang extract. 2. The increase of serum alanine aminotransferase induced by bile duct ligation was inhibited by the administration of Mockhyangjokisan and Haewooljoweetang extract. 3. The increased level of serum AST and AL T induced by the intraperitoneal injection of dimethylnitrosamine was inhibited by the administration of Mockhyangjokisan and Haewooljoweetang extract. 4. The increasing level of hydroxyproline volume in the damaged liver tissues in the rat was decreased by the oral administration of Mockhyangjokisan and Haewooljoweetang extract. But there were no significant differences in the inhibition rate between the two experimental groups.

• Journal of Korean Home Economics Education Association
• /
• v.25 no.4
• /
• pp.29-46
• /
• 2013

The concepts of core competencies and achievement standards were newly introduced within national curriculum documents since the 2009 Revised National Curriculum. The purpose of this introduction was to develop a curriculum that reflects unique characteristics of each subject and for the effectiveness of student evaluation. The purpose of this study was to suggest a direction for the future national curriculum and achievement standards development through comparing the national curriculum and standards between South Korea and the U.S. In particular, this study focused on two aspects: 1) the hierarchical relationships and the structural system of achievement standards in the curricula of two countries, and 2) the details of differences in two countries' achievement standards of a specific content area, 'family'. The results are as follows: the Korean national curriculum includes core competencies was included in the objective statement, and standards were provided as a lower-level system, while the U.S. national standards was composed of hierarchical system of comprehensive standards(higher-level), contents standards(middle-level), and competencies(lower-level). This may be attributable to the difference in the definition of competencies. The analysis results of detailed contents of the curriculum was related to the terminologies used in curriculum documents of the two countries. For example, work and family balance was frequently mentioned in Korean document, while the U.S. national curriculum just displayed multiple roles of individuals rather than using the term explicitly. Also, terms such as happiness and welfare were frequently mentioned in Korean curriculum, while 'well-being' was more frequently used in the U.S. curriculum. These differences in usage of terms reflects the differences in cultural values and perspectives of the two countries.

• The Korean Journal of Air & Space Law and Policy
• /
• v.33 no.1
• /
• pp.261-284
• /
• 2018

The current international legal system does not provide a safeguard against the militarization and the weaponization of outer space. Although the term "peaceful use of outer space" in the 1967 Outer Space Treaty(OST) appears in official government statements or in multilateral space treaties, it is still without an authoritative definition in reviewing national practices. The ambiguous ban on weapons in Article IV of the OST allows countries to loophole on the deployment of other weapons other than nuclear weapons. Meanwhile "Draft Treaty on the Prevention of the Placement of Weapon in Outer Space and of the Threat or Use of Force against Outer Space Objects(PPWT)" to Conference on Disarmament (CD) commissioned by the UN General Assembly's Special Session jointly submitted by China and Russia in 2008 and later revised in 2014, attempting to define and prohibit the proliferation of weapons in outer space and provided definitions of prohibited weapons, are opposed by the US on the grounds that currently there is no arms race in outer space. Some experts support a hard law approach in which binding laws aimed at ultimately creating integrated and binding legal instruments in all aspects of the use of outer space should be adopted to regulate the military use of space. However as a temporary measure the soft law guidelines should be developed for the non liquiet, a situation where there is no applicable law. The soft law could be used to create support for the declaration of the treaties and to create international customary law. For example, the 1963 Declaration of Legal Principles Governing the Activities of States in the Exploration and Use of Outer Space that regulates the activities of the state in the exploration and use of the universe, and the 1992 Principles Relevant to the Use of Nuclear Power Sources in Outer Space will illustrated. While substantial portions of the former was codified later in the 1967 OST, the latter which, although written in somewhat mandatory terms, have been consistently complied with by states, have arguably become part of customary international law. On November 12, 1974, the General Assembly reaffirmed that the development of international law may be reflected inter alia, by declarations and resolutions of the General Assembly which may to that extent be taken into consideration by the International Court of Justice.

• Tuberculosis and Respiratory Diseases
• /
• v.48 no.4
• /
• pp.522-529
• /
• 2000

Backgrounds : Assessment of the presence and degree of reversibility of airflow obstruction is clinically important in patients with asthma or chronic obstructive pulmonary disease. The measurement of peak expiratory flow(PEF) is a simple, fast, and cheap method to assess the severity of obstruction and its degree of reversibility. Assessing the reversibility of airflow obstruction by peak expiratory flow(PEF) measurements is practicable in general practice, but its usefulness has not been well investigated. We compared PEF and $FEV_1$ in assessing reversibility of airflow obstruction in patients with chronic obstructive pulmonary disease or asthma and developed a practical criterion for assessing the presence of reversibility in general practice. Methods : PEF measurements were performed (Spirometry) in 80 patients(aged 24-78) with a history of asthma or chronic obstructive lung disease before and after the inhalation of 200 g salbutamol. The change in PEF was compared with the change in forced expiratory volume in one second($FEV_1$). Reversible airflow obstruction was analyzed according to American Thoracic Society(ATS) criteria. Results : A 12% increase above the prebronchodilator value and a 200ml increase in either FVC or $FEV_1$ reversibility were observed in 45%(36) of the patients. Relative operating characteristic(ROC) analysis showed that an absolute improvement in PEF of 30 l/min gave optimal discrimination between patients with reversible and irreversible airflow obstruction(the sensitivity and specificity of an increase of 30 l/min in detecting a 12% increase above the prebronchodilator value and a 200ml increase in either FVC or $FEV_1$ were 72.2% and 72.7% respectively, with a positive predictive value of 68.4%). Conclusions : Absolute changes in PEF can be used to diagnose reversible airflow obstruction.

• Tuberculosis and Respiratory Diseases
• /
• v.46 no.6
• /
• pp.826-835
• /
• 1999

Background : The $\beta_2$ adrenergic receptor ($\beta_2$ AR) polymorphisms occurring at amino acid position 16 (Arg to Gly), 27 (Gln to Glu), 34 (Val to Met), and 164 (Thr to Ile) are known to be functionally relevant and also disease-modifying in subjects with asthma. However the contribution of these polymorphisms to the development of the asthmatic phenotype or other markers for allergic disease remains to be established. Methods : 109 patients with bronchial asthma and 42 healthy person were included. Serum total IgE, allergen specific IgE, and skin prick test were performed to all of the subjects. $\beta_2$ AR polymorphisms were checked by mutated allele specific amplification (MASA) method. Results : The results were as follows. The frequencies of $\beta_2$ AR polymorphisms in asthmatic patients and healthy person were not statistically different(p>0.05). There was no association between $\beta_2$ AR polymorphisms of amino acid position 16, 27, 34 and the existence of atopy among asthmatic patients(p>0.05). Between asthmatic patients with or without elevated IgE level and $\beta_2$ AR polymorphisms of amino acid position 16, 27, 34, there was no statistically significant association(p>0.05). Conclusion : There was no difference in frequency of the $\beta_2$ AR polymorphism between asthmatic patients and healthy person. In the bronchial asthma, association of $\beta_2$ AR polymorphism and atopy/serum total IgE was not found.

• Tuberculosis and Respiratory Diseases
• /
• v.51 no.5
• /
• pp.437-447
• /
• 2001

Background: TNF-alpha is related to the generation of lung fibrosis in patients with UIP. The precise mechanism leading to lung fibrosis by TNF-alpha is unknown. However, the activation of a transcription factor like AP-1(down stream of c-jun N-terminal kinase, JNK) by TNF-alpha may be related to the induction of fibrogenic cytokines like PDGF or IGF-I. Furthermore, JNK was reported to be activated in the radiation-induced lung fibrosis model. This study examined JNK activity in patients with UIP. Methods : The expression of phosphorous JNK(p-JNK), macrophage/monocyte specific markers, CD68, and cytokeratin was evaluated by immunohistochemical(IHC) staining of lung tissues from patients with UIP and lung cancer. An in vitro kinase assay was performed with alveolar macrophages obtained by a bronchol-avleolar lavage from patients with UIP and healthy persons as the control. Results : The IHC stain showed that p-JNK is expressed in the almost all of the alveolar macrophages and smooth muscle cells in patients with UIP. In case of the normal areas of the lung from patients with lung cancer, the alveolar macrophages showed little p-JNK expression. Interestingly, increased JNK activity was not found in the in vitro kinase assay of the alveolar macrophages obtained from both patients with UIP and healthy persons as the control. Furthermore, 10 ng/mL of TNF-alpha failed to increase the JNK activity of the alveolar macrophages in both patients with UIP and healthy people. Conclusion : The JNK was activated constitutionally in patients with UIP. However, the role of JNK in the pathogenesis of lung fibrosis needs to be clarified.

• Tuberculosis and Respiratory Diseases
• /
• v.54 no.4
• /
• pp.378-385
• /
• 2003

Background : Wheezing is an important clue in the diagnosis of asthma. Previously, a Korean National asthma survey used a written questionnaire, containing the question, "Have you ever experienced a breathing sound-like 'sack-sack' or a flute sound (the Korean description for wheezing) during the last 12 months?" The response to this question showed a large discrepancy between the prevalence of wheezing and physician diagnosed asthma. This might have resulted partly from a misunderstanding of the question, due to an inadequate description for wheezing. This study was aimed at finding how well the layman understands the term "wheezing" when described as a breathing sound-like 'sack-sack', a whistle or a flute. Subjects and method : Sixty subjects, without experience of wheezing(group I), and 45 subjects, with chronic cough alleging wheezing(group II), were recruited from the Hallym University's Sacred Heart Hospital, in Anyang, Korea. Four different breathing sounds; vesicular, wheezing, tracheobronchial and crackle, were played for the subjects, without any experience with wheezing, and they were asked "which sound is most like that you would imagine when asked about a breathing sound-like 'sack-sack', a whistle or a flute?" This was followed by replaying the true wheezing sound, and then a global assessment was requested for the concordance between the real wheezing sound and the imagined wheezing sound. The wheezing sound was played for those subjects alleging wheezing, and they were asked, "have you really experienced that sound". Results : Only 46.7% of group I answered correctly, with 13.3% choosing the vesicular sound, 16.7% the tracheobronchial sound, 5.0% the crackle and 18.3% failed to answer. The concordance between their imagined wheezing and the real sound was $69.3{\pm}22.4%(mean{\pm}S.D.)$. 77.8% of group II recognized the correct sound as the one they had experienced. Conclusions : Language is not sufficient to the layman for describing natural sounds, such as wheezing.

• Tuberculosis and Respiratory Diseases
• /
• v.65 no.4
• /
• pp.301-307
• /
• 2008

Background: The triggering receptor expressed on myeloid cells-1 (TREM-1) is an activating receptor that is expressed on the surface of neutrophils and mature monocytes when stimulated with several microbial components, which can amplify the inflammatory response. This study analyzed the prognostic value of the sTREM-1 levels in patients with acute respiratory distress syndrome (ARDS). Methods: The bronchoalveolar lavage (BAL) fluid and blood was collected prospectively from 32 patients with ARDS, 15 survivors and 17 nonsurvivors. An enzyme-linked immunosorbent assay was performed to measure the sTREM-1. The following data was obtained: APACHE II score, Clinical Pulmonary Infection Score (CPIS), BAL fluid analysis, C-reative protein. Mortality in the ICU was defined as the end point. Results: The serum sTREM-1 level was significantly higher in the nonsurvivors than survivors ($54.3{\pm}10.3pg/ml$ vs. $22.7{\pm}2.3pg/ml$, p<0.05). The sTREM-1 level in the serum, but not in the BAL fluid, was an independent predictor of the ICU mortality (OR: 22.051, 95% CI: 1.780~273.148, p<0.016), and a cut-off value of ${\geq}33pg/ml$ yielded a diagnostic sensitivity of 71% and specificity of 93%. Conclusion: The serum sTREM-1 level may be a useful predictor of the outcome of ARDS patients.

• KDI Journal of Economic Policy
• /
• v.31 no.1
• /
• pp.105-138
• /
• 2009

Although the decline in fertility rate is generally observed along the history of economic development throughout the world, the continuing decline hitting below the replacement level in Korea over the recent years gathered serious social concerns on the ground that it accelerates the process of population aging. The total fertility rate in Koreareached 2.08 in 1983, and gradually fell to the levels of 1.08 in 2005 and 1.26 in 2007. The policy debate over the role of the government has been focused mainly on the level of theoretical discussion without substantial basis on firm empirical evidence and the determinants of fertility. The objective of the paper is to empirically investigate the fertility effect of the female wage, which is understood as one of the most important determinants of fertility in Koreasince 1980 focusing on one aspect of fertility, namely birth spacing. Using the Korean National Fertility Survey conducted in 2006, I estimate a duration model of first and second births taking into account individual heterogeneity, which turned out to be an important factor to control for. Compared with previous studies in the literature on the Korean fertility, the study has an advantage of using the complete pregnancy history of women in a more representative sample. Unlike the previous studies, the analysis also deals with the endogeneity of marriage by treating a certain age, rather than age at marriage, as the time in which a woman becomes exposed to the risk of pregnancy. The study shares the common problem in the literature on birth spacing of lacking relevant wage information for respondents in a retrospective survey. I estimate the wage series as a function of the basic characteristics using the annual Wage Structure Survey from 1980 to 2005, which is considered as a nationally representative sample for wage information of employees. The results suggest that the increase in female wage by 10 percent leads to a decrease in second birth hazard by 0.56~0.92 percentage points and that the increase in spouse's wage by the equal amount is accompanied by the increase in second birth hazard by 0.36~1.13 percentage points. These estimates are more precisely estimated and of smaller magnitude than those presented by the previous studies. The results are robust to the different specifications of the wage equation. The simulation analysis based on the predicted values shows that about 17% of the change in the second birth hazard over the period 1980 to 2005 was due to the change in the female wage. Although there is some limitation in data, the results can be viewed as one estimate of the role of female wage on the recent fertility decline in Korea. The question raised by the paper is not a normative one of whether a government should promote childbearing but a positive one thatexplains fertility decline. Therefore, if there is a wide consensus on promoting childbearing, the finding suggests that the policies designed to reduce the opportunity cost of women in the labor market would be effective. The recent movement of implementing a wide range of family-friendly policies including child care support, maternity leave, parental leave and tax benefit in developed countries should be understood in this context.