• International Journal of Stem Cells
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• v.16 no.1
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• pp.1-15
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• 2023

Liver organoids have gained much attention in recent years for their potential applications to liver disease modeling and pharmacologic drug screening. Liver organoids produced in vitro reflect some aspects of the in vivo physiological and pathological conditions of the liver. However, the generation of liver organoids with perfusable luminal vasculature remains a major challenge, hindering precise and effective modeling of liver diseases. Furthermore, vascularization is required for large organoids or assembloids to closely mimic the complexity of tissue architecture without cell death in the core region. A few studies have successfully generated liver organoids with endothelial cell networks, but most of these vascular networks produced luminal structures after being transplanted into tissues of host animals. Therefore, formation of luminal vasculature is an unmet need to overcome the limitation of liver organoids as an in vitro model investigating different acute and chronic liver diseases. Here, we provide an overview of the unique features of hepatic vasculature under pathophysiological conditions and summarize the biochemical and biophysical cues that drive vasculogenesis and angiogenesis in vitro. We also highlight recent progress in generating vascularized liver organoids in vitro and discuss potential strategies that may enable the generation of perfusable luminal vasculature in liver organoids.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.649-660
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• 2011

The purpose of this study was to compare the dietary life and nutrient intakes among elderly persons residing at nursing homes and their homes in order to provide fundamental data for improved foodservice and dietary management. We recruited 150 subjects at a nursing home stay and 150 home stay elderly persons for a survey. The results were as follows. There was no significant difference in frequency of napping between the two groups. The frequency of going out was higher in the home stay subjects, but regular exercise was higher in nursing home stay subjects. Subjects possessed the following diseases: dementia and digestive disorders for nursing home stay elderly men, blood vessel disorder and diabetes for home stay elderly men, digestive and blood vessel disorders for nursing home stay elderly women, and blood vessel and heart disease for home stay elderly women. In a health-related assessment, smoking, drinking, and teeth condition of nursing home stay subjects were not higher than those of home stay subjects. The ratio of subjects who ate meals everyday was higher in nursing home stay elderly women than in home stay women. While most nursing home subjects ate adequate amount of meals, home stay subjects ate until they were full. The daily energy intakes of men and women were 2,229.9 kcal and 2,302.1 kcal for nursing home subjects and 1,894.0 kcal and 1,885.9 kcal for home subjects, respectively. Nutrient intake was also higher in nursing home than home stay subjects. In summary, the dietary life of elderly persons residing in a nursing home was higher than that of elderly persons residing at their home from the view point of meal frequency, meal intake, and nutrient intakes. Therefore, systematic assessment and management of nutrition for elderly staying at a nursing home or at home alone should be conducted continually.

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.503-527
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• 1993

This paper describes a new method to create an animal model for TMJ internal derangement in the New Zealand white rabbits and the light and electron microscopical changes of posterior attachment of them. Twenty six rabbits(2.5-3.0kg), four normal and twenty two experimental, were used. The right disc of experimental animal was displaced anteriorly without sectioning the posterior attachment and tied to the zygomatic arch with nylon not to be reduced to the original position. The left TMJ was sham-operated to be compared with its right experimental one. Normal animals were sacrificed one day and eight weeks after experiment. Experimental animals were sacrificed one day, ten days, three weeks, five weeks and eight weeks after surgery respectively. They were fixed intravenously with $2\%$ glutaldehyde under general anesthesia and the samples of them were processed for light and electron microscopic examination. The purpose of this experiment is to make a suitable animal model of disc displacement without reduction for studying and understanding the cellular and morphologic events in posterior attachment of TMJ including early changes which were difficult to be observed in human TMJs. The results of this investigation suggest the following conclusions : 1. Authors induced anterior disc displacement surgically in rabbits with new method to examine histologic changes of posterior attachment. Tissue reactions of this model seem to be similar to those observed in human disc displacement. We think this animal model for anterior disc displacement may be used to explore and evaluate objectively the effects of many treatment modalities in disc displacements. 2. The animal disease model showed inflammation at early stage(one and ten days). At this stage there were mild-to-severe mononuclear inflammatory cell infiltration, numerous newly formed vessels, vessel dilatation and engormement and many fibroblasts. 3. At middle stage(three weeks), fibrosis occurred, where fibroblasts decreased in number, but their cytoplasm was profuse indicating high activity. Collagen fibers increased in number and the tissue looked more dense. 4. At late stage(five weeks and eight weeks) showed degenerative changes including perforation of posterior attachment, disintegration of collagen fiber bundles, degeneration of fibroblasts, metastatic ossification, and dystrophic calcification.

• Journal of Acupuncture Research
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• v.26 no.3
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• pp.115-131
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• 2009

Objectives: This survey was done in order to find out how Korean medical doctors derive pattern identification for acupuncture prescriptions in treating low back pain in real clinical practice. Methods : The survey questionnaire was developed by the committee of experts who major in acupuncture & moxibustion or statistics for acupuncture clinical trial protocol development. The questionnaires were distributed via e-mail to 75 members of Korean Acupuncture & moxibustion society from March 26th to April 14th in 2009. 57 members completed answers, and the computerized data were analyzed by SPSS 17.0 statistical program. Results : 1.57 Korean medical doctors selected meridian pattern identification based on the course of the meridians(44.6%), visceral pattern identification(32.1%), pattern identification based on cause of disease(14.3%) as the most commonly used pattern identification methods for acupuncture prescription when treating low back pain patients in real clinical practice. 2. In meridian pattern identification based on the course of the meridians, gallbladder meridian of hypochondriac region(13.0%), bladder meridian of lateral low back region(11.2%), governer vessel of central low back region(11.7%) were selected 3. In visceral pattern identification, yang deficiency of kidney(20.2%), deficiency of kidney(19.3%), liver(16.7%), yin deficiency of kidney(14.0%), violence qi of kidney(8.8%), small intestine(7.9%) were selected. Conclusions : In our e-mail survey, Korean medical doctors answered that Meridian Pattern Identification based on the course of the meridians is the most often used diagnosis method. Visceral pattern identification, pattern identification based on cause of disease, meridian pattern identification based on symptom and pattern identification based on qi-blood-yin-yang theory in order of frequency used, were selected for low back pain diagnosis in real clinical practice.

• The Korean Journal of Nuclear Medicine
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• v.34 no.6
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• pp.487-496
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• 2000

Purpose: The aim of this study is to investigate the reproducibility of the quantitative assessment of segmental wall motion and systolic thickening provided by an automatic quantitation algorithm. Materials and Methods: Tc-99m-MIBI gated myocardial SPECT with dipyridamole stress was performed in 31 patients with known or suspected coronary artery disease (4 with single, 6 with two, 11 with triple vessel disease; ejection fraction $51{\pm}14%$) twice consecutively in the same position. Myocardium was divided into 20 segments. Segmental wall motion and systolic thickening were calculated and expressed in mm and % increase respectively, using $AutoQUANT^{TM}$ software. The reproducibility of this quantitative measurement of wall motion and thickening was tested. Results: Correlations between repeated measurements on consecutive gated SPECT were excellent for wall motion (r=0.95) and systolic thickening (r=0.88). On Bland-Altman analysis, two standard deviation was 2 mm for repeated measurement of segmental wall motion, and 20% for that of systolic thickening. The weighted kappa values of repeated measurements were 0.807 for wall motion and 0.708 for systolic thickening. Sex, perfusion, or segmental location had no influence on reproducibility. Conclusion: Segmental wall motion and systolic thickening quantified using $AutoeUANT^{TM}$ software on gated myocardial SPECT offers good reproducibility and is significantly different when the change is more than 2 mm for wall motion and more than 20% for systolic thickening.

• The Korean Journal of Nuclear Medicine
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• v.29 no.4
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• pp.478-483
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• 1995

We compared the influences of reconstruction methods using $180^{\circ}$ or $360^{\circ}$ data upon contrasts and discriminating capability and diagnostic accuracy in $^{99m}Tc-MIBI$ stress/rest myocardial SPECT. We reviewed SPECT images reconstructed only with $180^{\circ}$ projection data or with $360^{\circ}$ data in 18 patients and in 11 normal subjects. To compare counts of surface structures and deep structures, we measured ape# posterior wall ratios in 11 normal subjects. To compare the contrasts of images, we measured apex/ventricle ratios. To compare contrasts between normal and diseased myocardial segments, we measured count ratios of defect and normal segments in 4 patients who had single coronary artery diseases. To compare diagnostic accuracy, we scored SPECT images made with $180^{\circ}$ and $360^{\circ}$ data segmentally. Sensitivity and specificity for the diagnosis of coronary artery disease and for the revelation of diseased arteries with both $180^{\circ}$ and $360^{\circ}$ SPECT images. If involved coronary arteries had more narrowing than 50% In coronary angiogram, we considered them as diseased arteries Apex/posterior wall ratios were not different significantly in normal subjects. Apex/ ventricle ratios in normal subjects were different significantly between $180^{\circ}$ and $360^{\circ}$ SPECT images. Defect/normal ratios were different significantly between $180^{\circ}$ and $360^{\circ}$ SPECT images in single vessel disease patients. The overall diagnostic accurracy was the same between $180^{\circ}$ and $360^{\circ}$ data collection. Sensitivity was 94% and specificity was 91% for both types of data collection in this sample population. Sensitivity and specificity of each coronary artery territory were not significantly different between the images made with $180^{\circ}$ and $360^{\circ}$ data. The images made with $180^{\circ}$ data had better contrast between ventricle and myocardium and between hypoperfused and normal myocardium, though no difference was found between the ratios of the myocardial counts of surface and deep structures. However, diagnostic sensitivities of diseased artery territories were not different significantly and so were overall diagnostic accuracy between both methods of making images with $180^{\circ}$ and $360^{\circ}$ data.

• The Korean Journal of Nuclear Medicine
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• v.27 no.1
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• pp.59-64
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• 1993

To evaluate the usefulness and differences in diagnosing coronary artery disease (CAD) between men and women of intravenous dipyridamole $^{99m}Tc$-MIBI myocardial SPECT, we obtained $^{99m}Tc$-MIBI myocardial SPECT and compared with the findings of coronary angiographies. Ninety eight male and 37 female patients who underwent dipyridamole $^{99m}Tc$-MIBI myocardial imaging within one month of cardiac catheterization were studied. Scans were considered abnormal if perfusion defect was detected and the defect size was more than 12% for left anterior descending artery (LAD) and circumflex (LCX) and 8% for right coronary artery (RCA) territories. Lesions${\geqq}$50% luminal diameter narrowing were considered significant CAD. Overall sensitivity for detection of CAD was 94.3% in men and 96.4% in women; specificity was 70% in men and 52.6% in women (P=not significant, ns). Vessel-matched sensitivity was 75.3% in men and 72.7% in women (P=ns): specificity was 84.6% in men and 67.9% in women (P < 0.025). For individual coronary artery, the sensitivity in men and women was 87.7%, 81.8% for LAD; 78%, 83.3% for RCA and 52.2%, 46.7% for LCX (P=ns): the specificity was 80%, 40% for LAD (P<0.01), 82.5%, 68.4% for RCA, 88.9%, 86.4% for LCX (P=ns). The hemodynamic parameter after intravenous dipyridamole in men and women were significantly changed; the heart rate was increased and systolic, diastolic blood pressure was decreased. Adverse effects were reported in 58.8% of men and 72.7% in women (P=ns). The incidence of chest pain and headache were higher in women. There was no significant difference in the incidences of nausea, abdominal pain, dizziness, facial flushing, dyspnea. In conclusion, dipyridamole $^{99m}Tc$-MIBI myocardial SPECT is a safe, noninvasive test for evaluation of CAD. There was no gender difference to detect CAD, but more false-positive rate in women especially in the territory of LAD.

• Journal of Chest Surgery
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• v.41 no.2
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• pp.277-280
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• 2008

Tuberculous aortitis is a very rare disease. Furthermore, it is all the more rare for it to be complicated by the development of an aortic aneurysm or the formation of aorto-bronchial fistula. If it is complicated by rupture of the aorta, mortality is very high. If the patient didn't contract tuberculosis, but was expectorating blood, we would have to carry out a chest CT promptly, in order to make a rapid and accurate diagnosis of this disease. A 46-year-old male patient was admitted due to the sudden onset of intermittent hemoptysis and chest discomfort. CT scans of the chest showed an aneurysmal change to the descending thoracic aorta, and the formation of an aorto-bronchial fistula, which originated from this aneurysm and communicated with its left lower lobe. We operated with an artificial vessel graft interposition of the descending thoracic aorta and a left lower lobectomy. Because the diagnosis was of tuberculosis, we started anti-Tbc medication and long term anti-Tbc medication was recommended.

• Korean Journal of Veterinary Research
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• v.46 no.3
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• pp.177-184
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• 2006

Experimental autoimmune encephalomyelitis (EAE) is a disease model of multiple sclerosis (MS) that is characterized by remittance and relapse of the disease and autoimmune and demyelinating lesions in the central nervous system (CNS). Autoimmune inflammation is maintained by secretion of a large number of protein. Previous studies have suggested that transcripts encoding osteopontin (OPN) are frequently detected in the mRNA population of MS plaques. To elucidate the functional role of OPN in initiation and development of EAE, we examined the expression and localization of OPN in the spinal cord during acute EAE. We demonstrated that OPN significantly increased at the early stage of EAE and slightly declined thereafter by western blot analysis. An immunohistochemical study revealed that OPN was constitutively expressed in some glial cells (microglia, astrocytes) of white matter and neurons in the CNS of control rats. OPN expression was shown to be increased in the same cells at the early and peak stage of EAE. To identity cells expressing OPN by double-immunofluorescence labeling, we labeled rat spinal cord sections for OPN with a monoclonal OPN antibody and with mAbs for astrocyte (GFAP), microglia/macrophage (OX42)-specific markers. The major cell types of OPN-expressing cells were activated astrocytes and microglia in the adjacent inflammatory lesions. Interestingly, OPN was mainly expressed in the end feet of astrocytes around vascular cell adhesion molecule-1 (VCAM-1) expressing endothelial cells of CNS blood vessel. These findings suggest that increased levels of OPN in activated glial cell may play an important role in the recruitment of inflammatory cells into the CNS parenchyma during EAE.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.2
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• pp.69-78
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• 2016

Ischemic stroke is a disease that the brain tissues cannot function by reducing blood flow due to thrombosis or embolisms. Due to the nature of the disease, it is most important to identify the status of cerebral vessel and the medical images are necessarily used for its diagnosis. Among many indicators, brain MRI is most widely utilized because experts can effectively obtain the semantic information such as cerebral anatomy aiding the diagnosis with it. However, in case of emergency diseases like ischemic stroke, even though a intelligent system is required for supporting the prompt diagnosis and treatment, the current systems have some difficulties to provide the information of medical images intuitively. In other words, as the current systems have managed the medical images based on the basic meta-data such as image name, ID and so on, they cannot consider semantic information inherent in medical images. Therefore, in this paper, to provide core information like cerebral anatomy contained in brain MRI, we suggest a template-driven medical images mapping method. The key idea of the method is defining the mapping characteristics between anatomic feature and representative images by using template images that can be representative of the whole brain MRI image set and revealing the semantic relations that only medical experts can check between images. With our method, it will be possible to manage the medical images based on semantic.