• Journal of Plant Biotechnology
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• v.33 no.3
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• pp.195-207
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• 2006

Stem cells are the primordial, initial cells which usually divide asymmetrically giving rise to on the one hand self-renewals and on the other hand progenitor cells with potential for differentiation. Zygote (fertilized egg), with totipotency, deserves the top-ranking stem cell - he totipotent stem cell (TSC). Both the ICM (inner cell mass) taken from the 6 days-old human blastocyst and ESC (embryonic stem cell) derived from the in vitro cultured ICM have slightly less potency for differentiation than the zygote, and are termed pluripotent stem cells. Stem cells in the tissues and organs of fetus, infant, and adult have highly reduced potency and committed to produce only progenitor cells for particular tissues. These tissue-specific stem cells are called multipotent stem cells. These tissue-specific/committed multipotent stem cells, when placed in altered environment other than their original niche, can yield cells characteristic of the altered environment. These findings are certainly of potential interest from the clinical, therapeutic perspective. The controversial terminology 'somatic stem cell plasticity' coined by the stem cell community seems to have been proved true. Followings are some of the recent knowledges related to the stem cell. Just as the tissues of our body have their own multipotent stem cells, cancerous tumor has undifferentiated cells known as cancer stem cell (CSC). Each time CSC cleaves, it makes two daughter cells with different fate. One is endowed with immortality, the remarkable ability to divide indefinitely, while the other progeny cell divides occasionally but lives forever. In the cancer tumor, CSC is minority being as few as 3-5% of the tumor mass but it is the culprit behind the tumor-malignancy, metastasis, and recurrence of cancer. CSC is like a master print. As long as the original exists, copies can be made and the disease can persist. If the CSC is destroyed, cancer tumor can't grow. In the decades-long cancer therapy, efforts were focused on the reducing of the bulk of cancerous growth. How cancer therapy is changing to destroy the origin of tumor, the CSC. The next generation of treatments should be to recognize and target the root cause of cancerous growth, the CSC, rather than the reducing of the bulk of tumor, Now the strategy is to find a way to identify and isolate the stem cells. The surfaces of normal as well as the cancer stem cells are studded with proteins. In leukaemia stem cell, for example, protein CD 34 is identified. In the new treatment of cancer disease it is needed to look for protein unique to the CSC. Blocking the stem cell's source of nutrients might be another effective strategy. The mystery of sternness of stem cells has begun to be deciphered. ESC can replicate indefinitely and yet retains the potential to turn into any kind of differentiated cells. Polycomb group protein such as Suz 12 repress most of the regulatory genes which, activated, are turned to be developmental genes. These protein molecules keep the ESC in an undifferentiated state. Many of the regulator genes silenced by polycomb proteins are also occupied by such ESC transcription factors as Oct 4, Sox 2, and Nanog. Both polycomb and transcription factor proteins seem to cooperate to keep the ESC in an undifferentiated state, pluripotent, and self-renewable. A normal prion protein (PrP) is found throughout the body from blood to the brain. Prion diseases such as mad cow disease (bovine spongiform encephalopathy) are caused when a normal prion protein misfolds to give rise to PrP$^{SC}$ and assault brain tissue. Why has human body kept such a deadly and enigmatic protein? Although our body has preserved the prion protein, prion diseases are of rare occurrence. Deadly prion diseases have been intensively studied, but normal prion problems are not. Very few facts on the benefit of prion proteins have been known so far. It was found that PrP was hugely expressed on the stem cell surface of bone marrow and on the cells of neural progenitor, PrP seems to have some function in cell maturation and facilitate the division of stem cells and their self-renewal. PrP also might help guide the decision of neural progenitor cell to become a neuron.

• Journal of agricultural medicine and community health
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• v.30 no.1
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• pp.15-28
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• 2005

Objectives: The purpose of this cross-sectional study was aimed to investigate the status of bowel health behaviors, prevalence of constipation and risk factors related to self-reported constipation in high school students. Methods: The study subjects were 1,882 students of six high schools located in a metropolitan city, who were selected by the accidental sampling from June to August, 2002. We analyzed the data by frequency analysis, chi-square test, and multivariate logistic regression using SPSS ver. 10.0. Results: The result of this study were summarized as follows: 1. A prevalence rate of self-reported constipation was 25.2%. A rate in male students was 13.4% and in female students 36.5%. 2. In regard to therapeutic behavior, 52.1% of study student with change in bowel habit had not find particular counsellor, 38.9% of the student had counselling with parents. 16.3% of students in constipation group had taken laxative medicine for treating the constipation. 73.5% of the student in constipation group had suffered from anal pain during defecation, but 48.0% in normal group. 41.6% of the student in constipation group had a experience of rectal bleeding after defecation, but 23.7% in normal group. So constipation related symptoms distribution had showed statistically significant difference between two group. 3. From the multivariate analysis by self-reported method, the risk factors related to the constipation were sex(female), experience of diet for weight reduction, absence of the breakfast and intake of vegetable more than 3 times per weeks. Conclusions: we had reconfirmed that we should improve eating habits to prevent and treat the constipation in a result of this study. Intervention that is target to girl students, abstain from weight reduction diet, regularity of taking meals, intake more vegetables, stress management should be provided to prevent the constipation especially in Korean high school students. Further prospective designed study are needed to establish the causal-effect relationship between so many risk factors with constipation.

• Tuberculosis and Respiratory Diseases
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• v.40 no.6
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• pp.677-682
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• 1993

Background: Massive hemoptysis is a major clinical problem with high mortality. Bronchial artery embolization is well accepted and widely used for treatment of massive and recurrent hemoptysis, especially in patients with chronic diffuse pulmonary disease who are poor candidates for surgery. We evaluated the therapeutic effect of transcatheter arterial embolization for immediate control and prevention of recurrent hemoptysis. Method: We reviewed 20 cases(M:F=13:7) of bronchial artery embolization for the management of massive hemoptysis from Jun 1989 to Aug 1992 retrospectively. Results: Underlying causes of hemoptysis were pulmonary tuberculosis(n=14), bronchiectasis(n=3), aspergilloma(n=2) and paragonimiasis(n=1). Embolization material was choosed randomly gelfoam(n=7) or Ivalon(n=11) and in 2 cases both were used simultaneously. Target arteries of embolization were bronchial artery only in 15 cases, non-bronchial systemic arteries with or without bronchial artery in 5 cases. After the arterial embolization, immediate cessation of hemoptysis was achieved in 17 cases(85%) and total recurrence rate including 3 cases of immediate treatment failure was 50%. Among recurrences 3 cases were achieved lobectomy, 1 case was expired by asphyxia due to massive hemoptysis and remained 6 were managed by medical conservative treatment with no further recurrence of hemoptysis during follow up periods. Conclusion: Bronchial artery embolization for treatment of massive or recurrent hemoptysis was effective in immediate bleeding control. Despite high recurrence rate the rebleeding after embolization was less severe and controllable by conservative management. Bronchial artery embolization is valuable as primary trial to massive hemoptysis.

• Journal of Life Science
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• v.25 no.4
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• pp.463-472
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• 2015

Adrenomedullin (AM) is a peptide expressed in all body tissues, and its related receptors are increased in liver fibrosis. In this study, we evaluated the effect of AM deficiency on liver fibrogenesis induced by $CCl_4$ using AM heterozygous (HT) mice. The animals received a single injection of $CCl_4$ or olive oil for the acute experiment, and received $CCl_4$ or olive oil three times a week for 6 weeks for the chronic experiment. Fibrosis was accessed using histopathological analysis and the western blot. The AM HT mice showed mild pericentrilobular degeneration when compared to the AM wild type (WT) mice. In the acute experiment, there was no significant difference between the AM WT and AM HT mice. However, in the chronic experiment, the $CCl_4$-treated AM HT mice showed more severe liver fibrosis than that of the CCl₄-treated AM WT mice. The AST and ALT levels of the AM HT $CCl_4$ group were higher than those of the AM WT CCl₄ group. Additionally, the collagen deposition, $\alpha$- SMA protein and TGF-$\beta$ protein were increased in the AM HT $CCl_4$ group when compared to the AM WT $CCl_4$ group. The AM HT mice also exhibited severe lipid peroxidation through the GSH decrement. Taken together, our data suggest that AM deficiency increases the susceptibility to liver fibrosis induced by $CCl_4$, indicating a novel therapeutic target for patients with liver fibrosis.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.1
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• pp.35-41
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• 2019

Objectives : Although delirium is a common complication among patients hospitalized in intensive care units(ICUs), little is known about the roles that diagnostic and therapeutic procedures play in its development. This study investigates the procedure-related risk factors of delirium in ICU patients. Methods : All the consecutive patients admitted to the ICU between June 2016 and May 2017 were routinely evaluated for delirium by psychiatrists. In total, 1156 patients met the inclusion criteria and were retrospectively analyzed. A multiple logistic regression analysis was conducted to investigate independent risk factors of delirium development while adjusting for other characteristics. Results : The age, Acute Physiology and Chronic Health Evaluation (APACHE II) score, proportion of patients who had undergone an operation, and proportion of patients who were foley catheterized, mechanically ventilated, and physically restrained were higher in the delirium group. The multiple logistic regression analysis confirmed that the use of restraint was an independent risk factor of delirium (odds ratio : 10.006 ; 95% confidence interval : 6.120-16.360 ; p<0.001). The patient factors independently associated with delirium were an advanced age and a higher APACHE II score. The incidence of delirium was 15.3%. Conclusions : There is a high prevalence of delirium influenced by potentially harmful procedures in patients in ICU settings. The use of physical restraint had the strongest association with the development of delirium. These findings advocate the need to target procedure-related risk factors such as the use of restraints as preventive intervention measures for ICU delirium.