• Geomechanics and Engineering
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• v.36 no.4
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• pp.355-366
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• 2024

The original elastoplastic Hardening Soil model is formulated actually partly under hexagonal pyramidal Mohr-Coulomb failure criterion, and can be only used in specific stress paths. It must be completely generalized under Mohr-Coulomb criterion before its usage in engineering practice. A set of generalized constitutive equations under this criterion, including shear and volumetric yield surfaces and hardening laws, is proposed for Hardening Soil model in principal stress space. On the other hand, a Mohr-Coulumb type yield surface in principal stress space comprises six corners and an apex that make singularity for the normal integration approach of constitutive equations. With respect to the isotropic nature of the material, a technique for processing these singularities by means of Koiter's rule, along with a transforming approach between both stress spaces for both stress tensor and consistent stiffness matrix based on spectral decomposition method, is introduced to provide such an approach for developing generalized Hardening Soil model in finite element analysis code ABAQUS. The implemented model is verified in comparison with the results after the original simulations of oedometer and triaxial tests by means of this model, for volumetric and shear hardenings respectively. Results from the simulation of oedometer test show similar shape of primary loading curve to the original one, while maximum vertical strain is a little overestimated for about 0.5% probably due to the selection of relationships for cap parameters. In simulation of triaxial test, the stress-strain and dilation curves are both in very good agreement with the original curves as well as test data.

• IMMUNE NETWORK
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• v.21 no.2
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• pp.17.1-17.10
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• 2021

Abdominal aortic aneurysm (AAA) is a chronic dilation of the aorta with a tendency to enlarge and eventually rupture, which constitutes a major cause of cardiovascular mortality. Although T-cell infiltrates have been observed in AAA, the cellular, phenotypic, and functional characteristics of these tissue-infiltrating T cells are not fully understood. Here, we investigated the proportional changes of T-cell subsets-including CD4⁺ T cells, CD8⁺ T cells, and γδ T cells-and their effector functions in AAAs. We found that Vδ2⁺ T cells were presented at a higher frequency in aortic aneurysmal tissue compared to normal aortic tissue and PBMCs from patients with AAA. In contrast, no differences were observed in the frequencies of CD4⁺, CD8⁺, and Vδ1⁺ T cells. Moreover, we observed that the Vδ2⁺ T cells from AAA tissue displayed immunophenotypes indicative of CCR5⁺ non-exhausted effector memory cells, with a decreased proportion of CD16⁺ cells. Finally, we found that these Vδ2⁺ T cells were the main source of IL-17A in abdominal aortic aneurysmal tissue. In conclusion, our results suggest that increased Vδ2⁺ T cells that robustly produce IL-17A in aortic aneurysmal tissue may contribute to AAA pathogenesis and progression.

• Anatomy and Cell Biology
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• v.57 no.1
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• pp.45-60
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• 2024

Morphologic changes in the brain through aging, as a physiologic process, may involve a wide range of variables including ventricular dilation, and sulcus widening. This study reports normal ranges of these changes as standard criteria. Normal brain computed tomography scans of 400 patients (200 males, 200 females) in every decade of life (20 groups each containing 20 participants) were investigated for subcortical/cortical atrophy (bicaudate width [BCW], third ventricle width [ThVW], maximum length of lateral ventricle at cella media [MLCM], bicaudate index [BCI], third ventricle index [ThVI], and cella media index 3 [CMI3], interhemispheric sulcus width [IHSW], right hemisphere sulci diameter [RHSD], and left hemisphere sulci diameter [LHSD]), ventricular symmetry. Distribution and correlation of all the variables were demonstrated with age and a multiple linear regression model was reported for age prediction. Among the various parameters of subcortical atrophy, BCW, ThVW, MLCM, and the corresponding indices of BCI, ThVI, and CMI3 demonstrated a significant correlation with age (R²≥0.62). All the cortical atrophy parameters including IHSW, RHSD, and LHSD demonstrated a significant correlation with age (R²≥0.63). This study is a thorough investigation of variables in a normal brain which can be affected by aging disclosing normal ranges of variables including major ventricular variables, derived ventricular indices, lateral ventricles asymmetry, cortical atrophy, in every decade of life introducing BW, ThVW, MLCM, BCI, ThVI, CMI3 as most significant ventricular parameters, and IHSW, RHSD, LHSD as significant cortical parameters associated with age.

• Journal of Digestive Cancer Research
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• v.7 no.1
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• pp.18-21
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• 2019

Serine protease inhibitor Kazal-type 1 (SPINK1) is a gene expressed from pancreatic acinar cell which its mutation is known to be associated with chronic pancreatitis (CP) and pancreatic cancer. We report a case of a 47-years-old female with nausea and weight loss with yellow discoloration of skin. Initial imaging and endoscopic study led us to an impression of chronic pancreatitis with pancreatic cancer with common bile-duct dilation. Biopsy result was confirmed with pancreatic adenocarcinoma and additional imaging revealed lymph node and bone metastasis. Our genetic analysis revealed 194+2T>C mutation of SPINK1. Biliary obstruction was successfully decompressed by stent insertion and underwent chemotherapy and radiotherapy. Although there is accumulating evidence of association between SPINK1 mutation and CP, the relationship between SPINK1 mutation and pancreatic cancer in CP patient is an emerging concept. Genetic analysis should be considered in patients with young age especially when diagnosed with both CP and pancreatic cancer.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.2
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• pp.88-93
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• 2011

Purpose: As to analytical method of data, the AutoQUANT software in which it is used quantitative rating of the myocardial perfusion SPECT are reported that there is a difference. Therefore the measured value error of the mutual program is expected to be generated even if the quantitative analysis is made data of the same patient. The purpose of this study is to offer the comparative analysis of myocardial extract method in Quantitative Perfusion SPECT. Materials and methods: We analyzed the 51 patients who were examined by Tc-99m MIBI gated myocardial SPECT in nuclear medicine department of Pusan National University Hospital from June to December 2010(34 men, 17 women, mean age $66.5{\pm}9.9$). We acquired the extracted image in myocardial extract protocol. QPS program that uses the AutoQUANT software measured TID(Transient Ischemic Dilation), ESD(Extent of Stress Defect), SSS(Summed Stress Score). Then analyzed the results. Results: The correlation of appyling myocardial extract is TID(r=0.98), ESD(r=0.99), SSS(r=0.99). In the 95% confidence limit, there was no satistically significant difference(TID p=0.78, ESD p=0.31, SSS p=0.19). After blinding test with a physician for making a qualitative analysis, there was no difference. Conclusion: Quantitative indices in QPS program showed good correlation and the results showed no statistically signigicant difference. The variance between method was small. therefore, the functional parameters by each method can be used interchangeably. Also, we expect patient's satisfaction.

• Journal of Veterinary Clinics
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• v.31 no.2
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• pp.85-89
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• 2014

Arterial thromboembolism (ATE) is a common and fatal complication of hypertrophic cardiomyopathy (HCM) in cats. Therefore in this study, we evaluated the hypercoagulability (using plasma concentration of D-dimer) in HCM cats with different stage of heart failure and left atrial enlargement and also investigated the any correlation with echocardiographic indices (including left free wall thickness at diastole, interventricular septal thickness at diastole, LA to Ao ratio, heart failure stage, existence of systolic anterior motion of mitral valve). The median plasma D-dimer concentration in this study population was $0.51{\pm}0.70$ (range 0 to 2.50) ug/mL in the control group, $1.47{\pm}1.29$ (range 0.3 to 5.79) ug/mL in the HCM group, $1.48{\pm}1.65$ (range 0.3 to 5.79) ug/mL in the ISACHC I group, $1.62{\pm}0.4$ (range 1.31 to 2.07) ug/mL in the ISACHC II group, $1.36{\pm}0.91$ (range 0.3 to 2.31) ug/mL in the ISACHC III group, $1.90{\pm}1.60$ (range 0.3 to 5.79) ug/mL in the cat with LA dilation, $1.72{\pm}0.72$ (range 0.6 to 2.31) ug/mL in cats with SEC-T, $1.19{\pm}0.70$ (range 0.3 to 2.31) ug/mL in the cats with SAM, and $1.63{\pm}0.80$ (range 0.6 to 2.31) ug/mL in the cats with ATE. Our study found the median and mean concentration of plasma D-dimer was higher in cat with HCM, ATE, SECT and SAM and clearly provides evidence of hypercoagulability in cats with HCM, although the severity was not correlated to the dilation of LA and the presence of heart failure. This is the first study evaluating the hypercoagulability in cats with HCM in Korea.

• Journal of Chest Surgery
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• v.36 no.12
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• pp.921-927
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• 2003

Arterial switch operation (ASO) has been the most effective surgical option for transposition of the great arteries. But, the inappropriate dilation of the neoaortic root has been reported and its effect on neoaortic valve function and growth of aorta has not been well documented. Material and Method: Forty-eight patients who underwent cardiac catheterization during follow up after arterial switch operation were included in this study. Arterial switch operation was performed at a median age of 18 days (range 1∼211 days). Preoperative cardiac catheterization was performed in 26 patients and postoperative catheterization was performed in all patients at 15.8$\pm$9.6 months after ASO. Postoperative ratios of the diameters of neoaortic annulus, root and aortic anastomosis against the descending aorta were compared to the size of preoperative pulmonary annular, root and sinotubular junction. Preoperative and operative parameters were analyzed for the risk factors of neoaortic insufficiency. Result: There were two clinically significant neoaortic insufficiencies (grade$\geq$II/IV) during follow up, one of which required aortic valve replacement. Another patient required reoperation due to aortic stenosis on the anastomosis site. Post-operatively, neoaortic annulus/DA ratio increased from 1.33$\pm$0.28 to 1.52$\pm$.033 (p=0.01) and neoaortic root/DA ratio increased form 2.02$\pm$0.40 to 2.56$\pm$0.38 (p<0.0001). However, the aortic anastomosis/DA ratio showed no statistically significant difference (p=0.06). There was no statistically significant correlation between the occurrence of neoaortic insufficiency and neoaortic annulus/DA ratio and neoaortic root/DA ratio. Non-neonatal repair (age>30days) (p=0.02), preopeative native pulmonaic valve stenosis (p=0.01), and bisuspid pulmonic valve (p=0.03) were the risk factors for neoaortic insufficiency in univariate risk factor analysis. Conclusion: After ASO, aortic anastomosis site showed normal growth pattern proportional to the descending aorta, but neoaortic valve annulus and root were disproportionally dilated. Significant neoaortic valve insufficiency rarely developed after ASO and neoaortic annulus and root size do not correlate with the presence of postoperative neoarotic insufficiency. ASO after neonatal period, preoperative native pulmonary valve stenosis, and bicuspid native pulmonic valve are risk factors for the development of neoaortic insufficiency.

• Journal of radiological science and technology
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• v.30 no.2
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• pp.95-104
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• 2007

In this study, the analysis on findings from simple chest radiography(CXR) test with total 1,669 subjects without any special clinical symptom came to the following conclusions : 1. In terms of the general characteristics of subjects hereof, male and female group accounted for 55.2% and 44.8% respectively out of all 1,669 people. 2. Pulmonary disease cases amounted to 249 persons(14.9%) out of all subjects. 3. In the analysis on prevalence rate by age distribution, it was noted that the older age led to the more number of diseases, which was demonstrated by age 34 or younger(6.1%), age $35{\sim}39(9.7%)$, age $40{\sim}49(13.3\;%)$, and age 50 or older(30.8%). 4. In regard of pulmonary disease alone, the region of onset was represented primarily by right upper lobe, which was followed by both upper lobe and left upper lobe, respectively. 5. In terms of disease types, it was found that most cases were represented by pulmonary nodule(55.0%), which was followed by cardiomegaly(24.5%), CP angle blunting(4.8%), scoliosis(4.6%), tortuous aorta(2.8%), bronchial luminal dilatation(2.4%), and pleural thickening(2.0%). However, dextrocardia, cystic dilation of bronchus, cavitary lesion, and lung collapse accounted for relatively low rate(0.4% respectively). 6. In terms of disease types by sex, it was found that male group accounted for higher percentage of having pulmonary nodule than female group, while the latter accounted for higher percentage of having cardiomegaly, tortuous aorta and scoliosis than the former. 7. In terms of disease types by age distribution, it was noted that age 34 or younger group accounted for higher percentage of scoliosis than any other age groups, while age $40{\sim}49$ group, age $35{\sim}39$ group, and age 50 or older group represented the case of CP angle blunting, pulmonary nodule, and cardiomegaly/tortuous aorta, respectively.

• Clinical and Experimental Pediatrics
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• v.49 no.4
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• pp.368-374
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• 2006

Purpose : The prevalence of obesity in children is increasing rapidly. Epidemiologic studies suggest that obesity induced atherosclerosis may start in childhood. We investigated whether obese children show early abnormalities of the arterial wall and endothelial dysfunction. Methods : Thirty-eight obese children(14-16 years old of age, male, body mass index $29.40{\pm}3.18kg/m^2$) and forty-five age and sex-matched healthy control children(body mass index $18.43{\pm}1.01kg/m^2$) were enrolled. Their carotid artery intima-media thickness(IMT) and brachial artery flowmediated dilation(FMD) response were measured by high-quality ultrasound system, and compliance, distensibility, stiffness index, incremental elastic modulus and wall stress were calculated by equation. In addition, we looked at the relations between these arterial features and metabolic cardiovascular risk factors. Results : The obese children had significantly increased IMT($0.52{\pm}0.09mm$ vs $0.40{\pm}0.07mm$, P< 0.001) and markedly impaired FMD($7.35{\pm}7.78$ percent vs $20.34{\pm}16.81$ percent, P<0.001) than the healthy controls. But the compliance and distensibility were lower, and the stiffness index, incremental elastic modules and wall stress were higher in the obese group than the control group, but not statistically significantly. Body mass index was highly associated with increased IMT(r=0.612, P<0.001) and reduced FMD(r=-0.414, P<0.001). Conclusion : We showed the deleterious effect of child obesity on both early functional and structural atherosclerotic markers. The ultrasonic findings will be used for screening and follow up markers to identify high-risk patients among obese children.

• Applied Microscopy
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• v.26 no.4
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• pp.465-477
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• 1996

The influence of dehydrocholic acid, cholesterol and phosphstidylcholie to the fine structure of vacuolar apparatus was investigated to better understand the mechanism of intracellular transport of bile constituents in the hepatocytes of rats. The cis Golgi cisterns faced toward the bile canaliculi both in normal and experimental groups. In the hepatocytes from the rats of experimental groups, the primary organic solutes in bile influence the Gogi apparatus, ER and lysosome in the way of increase, cisternal dilation or budding to form the vacuoles. In the dehydrocholic acid group, the cis Golgi cisterns appeared to be sacculated and showed buds, which were probably separated to be vacuoles. Some of the vacuoles appeared to be fused to the bile canaliculi. In the cholesterol and phosphatidylcholine groups, the Golgi cisterns appeared to be dilated and lysosomes were increased in the vicinity of bile canaliculi. The cis Golgi cisterns showing linear saccular fashions were occasonally observed. The increase of lysosomes were more predominant in the cholesterol group. The evidence suggests that dehydrocholic acid is mainly transported through the ER and cis Golgi cisterns, and cholesterol and phosphatidylcholine are mainly transported through the ER and lysosomes via the trans Golgi cisterns, but the cholesterols are frequently transported via the lysosomes.