• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.282-286
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• 1988

Growth kinetic parameters for mass cultivation of Chinese Hamster Ovary (CHO) cells are estimated by measuring oxygen uptake rates. It Is found that there is strong correlation between cell growth and oxygen consumption, showing that correlation factor is 0.83. Derived linear model predicts actual cell density very well. It tells that oxygen uptake rate can play important role in indirectly measuring cell density when conventional method of estimating cell density is no longer meaningful due to heavy cell clumpings. Cell yield per oxygen consumption, $Y_{\chi}o$ and mass transfer coefficient for oxygen, Ka are also estimated as 1.26$\times$10$^4$cells/mmole $O_2$ consumed and 1.01/h, respectively. Average specific growth rate over all runs is 2.891/day for CHO cells with producting 2 grams of tPA per day under continuous perfusion operations.

• Journal of Chest Surgery
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• v.18 no.4
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• pp.692-699
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• 1985

Fifty cases of Open Heart Surgery due to congenital and acquired heart disease were done using the cardiopulmonary bypass in the Department of Thoracic and Cardiovascular surgery, Chosun University Hospital from November, 1980 to June, 1985. 1. The age of the congenital heart disease was from 7 to 29 years, the mean age was 14.5 years. In the acquired heart disease, the age was from 14 to 48 years, and the mean age was 22.3 years. The ratio of male to female was about 1.8:1. 2. The number of congenital cyanotic heart disease were 7 patients, congenital acyanotic heart disease were 17 patients and acquired valvular heart disease were 26 patients. All of the acquired heart disease was one or more valve disease. 3. Preoperative symptoms of the congenital heart disease were exertional dyspnea [cyanotic 100%, acyanotic 70.6%] and palpitation [cyanotic 28.6%, acyanotic 76.1%], and the acquired heart diseases were exertional dyspnea [92.3%], palpitation [34.1 %], and chest discomfort [30.8%]. 4. The method of the myocardial protection during the cardiopulmonary bypass were mild or moderate hypothermia, intermittent coronary perfusion of the cardioplegic solution, topical myocardial hypothermia with 4oC Hartmann`s solution. 5. In the cases of the valve replacement, postoperative oral anticoagulant therapy was started at oral intake of food using the warfarin and persantin, and the prothrombin time was maintained 30-50% of control value during 3-6 months for tissue valve replacement and permanently for metal valve replacement. 6. The postoperative complications were appeared in 24 cases and the complications were wound infection, occipital alopecia, hemorrhage etc. 7. The mortality after open heart surgery was 8 percents and the cause of death was low cardiac output syndrome, right heart failure, DIC, and Left ventricle rupture.

• Journal of Chest Surgery
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• v.31 no.9
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• pp.845-854
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• 1998

Background: S-2-(3 aminoprophlamino) ethylphosphorothioic acid(WR-2721) is one of the radical scavenging thiols. We tested its protective effects in the reperfused heart. Material and Method: The experimental setup was the constant pressure Langendorffs perfusion system. We investigated the radical scavenging properties of this compound in isolated rat hearts which were exposed to 20 minutes ischemia and 20 minutes reperfusion. Four experimental groups were used:group I, control, Amifostine 50 mg(1 mL) peritoneal injection 30 minutes before ischemia(group II), Amifostine 10 mg(0.2 mL) injection during ischemia through coronary artery(group III),and Amifostine 50 mg(1 mL) peritoneal injection 2 hrs before ischemia(group IV). The experimental parameters were the levels of latate, CK-MB, and adenosine deaminase(ADA) in frozen myocardium, the quantity of coronary flow,and left ventricular developed pressure, and it's dp/dt. Statistical analysis was performed using repeated measured analysis of variance and student t-test. Result: The coronary flow of group II and IV were less than group I and III at equilibrium state but recovery of coronary flow at reperfusion state of group II, III, and IV were more increased compared with group I. The change of systolic left ventricular devoloping pressure of group II and IV were less than control group at equilibrium state, which seemed to be the influence of the pharmacological hypotensive effect of amifostine. But it was higher compared with group I at reperfusion state. The lactic acid contents of group II were less than control group in frozen myocardium.(Group I was 0.20 0.29 mM/g vs Group II, which was 0.10 0.11 mM/g). The quantity of CK-MB in myocardial tissue was highest in group IV (P=0.026 I: 120.0 97.8 U/L vs IV: 242.2 79.15 U/L). The adenosine deaminase contents in the coronary flow and frozen myocardium were not significantly different among each group. Conclusion: Amifostine seemed to have significant cardioprotective effect during ischemia and reperfusion injuries of myocardium.

• Journal of Korean Neurosurgical Society
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• v.38 no.6
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• pp.413-418
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• 2005

Objective : Although an encephaloduroarteriosynangiosis procedure using the superficial temporal artery [STA-EDAS] is an effective indirect bypass method in children with moyamoya disease[MMD], there is still a need for an additional bypass operation that can cover the area of the posterior circulation. The goal of this study is to evaluate the efficacy of the EDAS procedure using the occipital arteries [OA-EDAS]. Methods : From August 2003 to April 2004, We performed OA-EDAS in sixteen patients with MMD who have a circulatory insufficiency in the territory of the posterior cerebral artery[PCA]. The medical records were reviewed retrospectively. The surgical outcomes, including the changes in neurological status and imaging studies, with the degree of neovascularization on the cerebral angiogram, and the hemodynamic changes on single-photon emission computed tomography[SPECT], were analyzed. Results : These 16 children consisted of 5 boys and 11 girls aged 2 to 9 years. The clinical outcome of their PCA symptoms, such as visual transient ischemic attacks[TIAs] or visual field defect, was favorable in 14 patients of 16. Nine patients of 11 who underwent follow up magnetic resonance imaging[MRI] showed favorable MRI changes. On angiogram most of the patients exhibited good or fair revascularization of the PCA territory [7 of 8]. The hemodynamic changes on SPECT in the PCA territory after surgery showed improved vascular reserve in 13 of the 16 territories. Conclusion : OA-EDAS is a safe and efficacious revascularization procedure in patients with MMD who have compromised cerebral perfusion in PCA territory, or with visual TIAs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1173-1180
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• 1997

Hepatotoxicity of caffeine and acetaminophen was investigated in this study. Special attention was paid to the effect of vitamins on the reduction of hepatotoxicity caused by the chemicals. Rat hepaocytes isolated by two-step perfusion method were cultured in two differents methods-suspension, monolayer cultures-, and exposed to caffeine and/or acetaminophen for 24hrs. Caffeine or acetaminophen exhibited no significant hepatotoxicity in terms of intracellular glutathione(GSH) level and lipid peroxidation(MDA), but GSH level was significantly decreased after administrated acetaminophen, and the toxicity caused by the chemicals showed a dose-dependent manner. The synergistic effect of caffeine and acetaminophen was observed when both caffeine and acetaminophen were supplemented to culture medium. At the concentration 1mM, caffeine enhanced the intracellular GSH depletion and MDA formation by 63% and 64%, respectively, compared to single supplementation of 10mM acetaminophen in culture medium. This hepatotoxicity induced membrane integrity loss was observed by lightmicroscope on the simultaneous administration of caffeine and acetaminophen in monolayer cultured hepatocytes. Co-supplementation of vitamins with caffeine/acetaminophen to culture medium results in the protection of hepatocytes from hepatotoxic attach by caffeine/acetaminophen. Especially, vitamin E was superior to vitamin C and $\beta$-carotene from the standpoints of GSH depletion and MDA formation. From this results, it has been speculated that vitamin E may play a role of antioxidant scavenging radicals produced from acetaminophen. Taken all together, in vitro culture system like monolayer culture of hepatocytes may be a useful tool for the evaluation of hepatotoxicity or protection ability of food ingredients.

• Tissue Engineering and Regenerative Medicine
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• v.15 no.6
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• pp.781-791
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• 2018

BACKGROUND: Glucosamine hydrochloride (GlcN HCl) has been shown to inhibit cell growth and matrix synthesis, but not with N-acetyl-glucosamine (GlcNAc) supplementation. This effect might be related to an inhibition of critical growth factors (GF), or to a different metabolization of the two glucosamine derivatives. The aim of the present study was to evaluate the synergy between GlcN HCl, GlcNAc, and GF on proliferation and cartilage matrix synthesis. METHOD: Bovine chondrocytes were cultivated in monolayers for 48 h and in three-dimensional (3D) chitosan scaffolds for 30 days in perfusion bioreactors. Serum-free (SF) medium was supplemented with either growth factors (GF) $TGF-{\beta}$ ($5ng\;mL^{-1}$) and IGF-I ($10ng\;mL^{-1}$), GlcN HCl or GlcNAc at 1mM each or both. Six groups were compared according to medium supplementation: (a) SF control; (b) SF + GlcN HCl; (c) SF + GlcNAc; (d) SF + GF; (e) SF + GF + GlcN HCl; and (f) SF + GF + GlcNAc. Cell proliferation, proteoglycan, collagen I (COL1), and collagen II (COL2) synthesis were evaluated. RESULTS: The two glucosamines showed opposite effects in monolayer culture: GlcN HCl significantly reduced proliferation and GlcNAc significantly augmented cellular metabolism. In the 30 days 3D culture, the GlcN HCl added to GF stimulated cell proliferation more than when compared to GF only, but the proteoglycan synthesis was smaller than GF. However, GlcNAc added to GF improved the cell proliferation and proteoglycan synthesis more than when compared to GF and GF/GlcN HCl. The synthesis of COL1 and COL2 was observed in all groups containing GF. CONCLUSION: GlcN HCl and GlcNAc increased cell growth and stimulated COL2 synthesis in long-time 3D culture. However, only GlcNAc added to GF improved proteoglycan synthesis.

• Environmental Mutagens and Carcinogens
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• v.26 no.2
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• pp.53-58
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• 2006

Normally, environmental toxicants are classified as endocrine disruptors if they interfere with regulation of cellular function by endogeneous steroids through inhibition of receptor binding and/or transcriptional activation. So, many studies have been performed about agonist/antagonist of hormone receptor to study mechanisms of endocrine disruptors. If toxicants affect steroid biosynthesis and/or degradation and alter hormone homeostasis, these also are classified as endocrine disruptors. But there are not many studies of the mechanisms of endocrine disruptors on the basis of alteration of steroid biosynthesis and/or degradation. Isolation and culture of Leydig cells from testis is one of methods for the steroidogenesis screening assays to evaluate a substance for altering steroidogenesis. Leydig cells were harvested using the method described by Klinefelter with modifications. Leydig cells were purified by perfusion of testis and incubation ($34^{\circ}C$, 80cycles/minute, 20 minutes) with collagenase (0.25 mg/kg), centrifugal elutriation, percoll gradient centrifugation and BSA multidensity gradient centrifugation. To confirm if this method is one of appropriate tools to evaluate a substance for altering steroidogenesis, ketoconazole, positive control was administered to purified Leydig cells. Ketoconazole ($10^{-8}M$ and above) significantly reduced testosterone production in purified Leydig cells. From above results, we suggest that this method for steroidogenesis screening assay appears to be a appropriate tool to detect suspected compounds for altering steroidogenesis.

• Journal of the Korean Society of Radiology
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• v.13 no.5
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• pp.713-720
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• 2019

The purpose of this study was to propose a new measurement method for accurate measurement of vessel diameter in computed tomography angiography(CTA). CTA test was performed after non-ionic iodine contrast agent was flowed at a constant rate to self-maded perfusion phantom. After obtaining raw data, images were reconstructed with multi-planar reconstruction(MPR) and maximal intensity projection(MIP). Diameters of vascular models were measured for each technique. Relative and conventional measurements were then compared. The mean diameter of the vascular model was closer to the actual measurement when relative measurement was used compared to that when conventional measurement was used both in MPR and MIP. Relative measurements of MPR and MIP were closer to actual measurement than those of conventional measurement (34% VS, 24%, p<0.05). The relative measurement method proposed in this study was closer to the actual measurement than the conventional measurement method. However, both test methods were still larger than actual results. Therefore, further study of relative measurement method is needed using this study as basic data.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.3
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• pp.192-200
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• 2008

To evaluate the hemodynamic changes and the predictive factors of the clinical outcome in pediatric patients with moyamoya disease, we analyzed pre/post basal/acetazolamide stress brain perfusion SPECT with automated volume of interest (VOIs) method. Methods: Total fifty six (M:F = 33:24, age $6.7{\pm}3.2$ years) pediatric patients with moyamoya disease, who underwent basal/acetazolamide stress brain perfusion SPECT within 6 before and after revascularization surgery (encephalo-duro-arterio-synangiosis (EDAS) with frontal encephalo-galeo-synangiosis (EGS) and EDAS only followed on contralateral hemisphere), and followed-up more than 6 months after post-operative SPECT, were included. A mean follow-up period after post-operative SPECT was $33{\pm}21$ months. Each patient's SPECT image was spatially normalized to Korean template with the SPM2. For the regional count normalization, the count of pons was used as a reference region. The basal/acetazolamide-stressed cerebral blood flow (CBF), the cerebral vascular reserve index (CVRI), and the extent of area with significantly decreased basal/acetazolamide- stressed rCBF than age-matched normal control were evaluated on both medial frontal, frontal, parietal, occipital lobes, and whole brain in each patient's images. The post-operative clinical outcome was assigned as good, poor according to the presence of transient ischemic attacks and/or fixed neurological deficits by pediatric neurosurgeon. Results: In a paired t-test, basal/acetazolamide-stressed rCBF and the CVRI were significantly improved after revascularization (p<0.05). The significant difference in the pre-operative basal/acetazolamide-stressed rCBF and the CVRI between the hemispheres where EDAS with frontal EGS was performed and their contralateral counterparts where EDAS only was done disappeared after operation (p<0.05). In an independent student t-test, the pre-operative basal rCBF in the medial frontal gyrus, the post-operative CVRI in the frontal lobe and the parietal lobe of the hemispheres with EDAS and frontal EGS, the post-operative CVRI, and ${\Delta}CVRI$ showed a significant difference between patients with a good and poor clinical outcome (p<0.05). In a multivariate logistic regression analysis, the ${\Delta}CVRI$ and the post-operative CVRI of medial frontal gyrus on the hemispheres where EDAS with frontal EGS was performed were the significant predictive factors for the clinical outcome (p =0.002, p =0.015), Conclusion: With probabilistic map, we could objectively evaluate pre/post-operative hemodynamic changes of pediatric patients with moyamoya disease. Specifically the post-operative CVRI and the post-operative CVRI of medial frontal gyrus where EDAS with frontal EGS was done were the significant predictive factors for further clinical outcomes.

• Journal of Chest Surgery
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• v.39 no.5 s.262
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• pp.354-358
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• 2006

Background: Pulsatile pumps for extracorporeal circulation have been known to be better for tissue perfusion than non-pulsatile pumps but be detrimental to blood corpuscles. This study is intended to examine the risks and benefits of $T-PLS^{TM}$ through the comparison of clinical effects of $T-PLS^{TM}$ (pulsatile pump) and $Bio-pump^{TM}$ (non-pulsatile pump) used for coronary bypass surgery. Material and Method: The comparison was made on 40 patients who had coronary bypass using $T-PLS^{TM}\;and\;Bio-pump^{TM}$ (20 patients for each) from April 2003 to June 2005. All of the surgeries were operated on pump beating coronary artery bypass graft using cardiopulmonary extra-corporeal circulation. Risk factors before surgery and the condition during surgery and the results were compared. Result: There was no significant difference in age, gender ratio, and risk factors before surgery such as history of diabetes, hypertension, smoking, obstructive pulmonary disease, coronary infarction, and renal failure between the two groups. Surgery duration, hours of heart-lung machine operation, used shunt and grafted coronary branch were little different between the two groups. The two groups had a similar level of systolic arterial pressure, diastolic arterial pressure and mean arterial pressure, but pulse pressure was measured higher in the group with $T-PLS^{TM}\;(46{\pm}15\;mmHg\;in\;T-PLS^{TM}\;vs\;35{\pm}13\;mmHg\;in\;Bio-pump^{TM},\;p<0.05)$. The $T-PLS^{TM}$-operated patients tended to produce more urine volume during surgery, but the difference was not statistically significant $(9.7{\pm}3.9\;cc/min\;in\;T-PLS^{TM}\;vs\;8.9{\pm}3.6\;cc/min\;in\;Bio-pump^{TM},\;p=0.20)$. There was no significant difference in mean duration of respirator usage and 24-hour blood loss after surgery between the two groups. Plasma free Hb was measured lower in the group with $T-PLS^{TM}\;(24.5{\pm}21.7\;mg/dL\;in\;T-PLS^{TM}\;versus\;46.8{\pm}23.0mg/dL\;in\;Bio-pump^{TM},\;p<0.05)$. There was no significant difference in coronary infarction, arrhythmia, renal failure and morbidity rate of cerebrovascular disease. There was a case of death after surgery (death rate of 5%) in the group tested with $T-PLS^{TM}$, but the death rate was not statistically significant. Conclusion: Coronary bypass was operated with $T-PLS^{TM}$ (Pulsatile flow pump) using a heart-lung machine. There was no unexpected event caused by mechanical error during surgery, and the clinical process of the surgery was the same as the surgery for which $Bio-pump^{TM}$ was used. In addition, $T-PLS^{TM}$ used surgery was found to be less detrimental to blood corpuscles than the pulsatile flow has been known to be. Authors of this study could confirm the safety of $T-PLS^{TM}$.