• Economic and Environmental Geology
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• v.55 no.4
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• pp.407-419
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• 2022

Soil(vadose zone) gas compositions were measured for about 3 days to suggest a method for monitoring and interpreting soil gas data collected around wells from which methane(CH₄) is outflowing. The vadose zone gas samples were collected within 1 m around two test wells(TB2 and TB3) at Pohang and analyzed for CO₂, CH₄, N₂ and O₂ concentrations in situ. CO₂ flux was measured beside TB2. In addition, gas samples from well head in TB2 and atmospheric air samples were collected for comparison. Carbon isotopes of CO₂(δ¹³C_CO2) of samples collected on the last day of the study period were analyzed in the laboratory. The two test wells (TB2 and 3) were 12.7 m apart and only TB3 was cemented to the surface. According to the bio-geochemical process-based interpretation, the relationships between CO₂ and O₂, N₂, and N₂/O₂ of vadose zone gas were plotted between the lines of CH₄ oxidation and CO₂ dissolution. In addition, the CH₄ concentrations of gas samples from the wellhead of the uncemented well (TB2) were 5.2 times higher than the atmospheric CH₄ concentration. High CO₂ concentrations (average 1.148%) of vadose zone gas around TB2 seemed to be attributed to the oxidation of CH₄. On the other hand, the vadose zone CO₂ around the cemented well(TB3) showed a relatively low concentration(0.136%). This difference indicates that the vadose zone gas(including CO₂) around the CH₄ outflowing well were strongly affected by well completion(cementing). This study result can be used to establish strategies for environmental monitoring of soil around natural gas sites, and can be used to monitor leakage around injection and observation wells for CO₂ geological storage. In addition, the method of this study is useful for soil monitoring in natural gas storage and oil-contaminated sites.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.1
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• pp.44-49
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• 2017

Purpose Radiation exposure management has been strictly regulated for the radiation workers, but there are only a few studies on potential risk of radiation exposure to non-radiation workers, especially nurses in a general ward. The present study aimed to estimate the exact total exposure of the nurse in a general ward by close contact with the patient undergoing nuclear medicine examinations. Materials and Methods Radiation exposure rate was determined by using thermoluminescent dosimeter (TLD) and optical simulated luminescence (OSL) in 14 nurses in a general ward from October 2015 to June 2016. External radiation rate was measured immediately after injection and examination at skin surface, and 50 cm and 1 m distance from 50 patients (PET/CT 20 pts; Bone scan 20 pts; Myocardial SPECT 10 pts). After measurement, effective half-life, and total radiation exposure expected in nurses were calculated. Then, expected total exposure was compared with total exposures actually measured in nurses by TLD and OSL. Results Mean and maximum amount of radiation exposure of 14 nurses in a general ward were 0.01 and 0.02 mSv, respectively in each measuring period. External radiation rate after injection at skin surface, 0.5 m and 1 m distance from patients was as following; $376.0{\pm}25.2$, $88.1{\pm}8.2$ and $29.0{\pm}5.8{\mu}Sv/hr$, respectively in PET/CT; $206.7{\pm}56.6$, $23.1{\pm}4.4$ and $10.1{\pm}1.4{\mu}Sv/hr$, respectively in bone scan; $22.5{\pm}2.6$, $2.4{\pm}0.7$ and $0.9{\pm}0.2{\mu}Sv/hr$, respectively in myocardial SPECT. After examination, external radiation rate at skin surface, 0.5 m and 1 m distance from patients was decreased as following; $165.3{\pm}22.1$, $38.7{\pm}5.9$ and $12.4{\pm}2.5{\mu}Sv/hr$, respectively in PET/CT; $32.1{\pm}8.7$, $6.2{\pm}1.1$, $2.8{\pm}0.6$, respectively in bone scan; $14.0{\pm}1.2$, $2.1{\pm}0.3$, $0.8{\pm}0.2{\mu}Sv/hr$, respectively in myocardial SPECT. Based upon the results, an effective half-life was calculated, and at 30 minutes after examination the time to reach normal dose limit in 'Nuclear Safety Act' was calculated conservatively without considering a half-life. In oder of distance (at skin surface, 0.5 m and 1 m distance from patients), it was 7.9, 34.1 and 106.8 hr, respectively in PET/CT; 40.4, 199.5 and 451.1 hr, respectively in bone scan, 62.5, 519.3 and 1313.6 hr, respectively in myocardial SPECT. Conclusion Radiation exposure rate may differ slightly depending on the work process and the environment in a general ward. Exposure rate was measured at step in the general examination procedure and it made our results more reliable. Our results clearly showed that total amount of radiation exposure caused by residual radioactive isotope in the patient body was neglectable, even comparing with the natural radiation exposure. In conclusion, nurses in a general ward were much less exposed than the normal dose limit, and the effects of exposure by contacting patients undergoing nuclear medicine examination was ignorable.

• 한국유가공학회:학술대회논문집
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• 2007.09a
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• pp.49-58
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• 2007

Inflammatory process leads to the well-known mucosal damage and therefore a further disturbance of the epithelial barrier function, resulting abnormal intestinal wall function, even further accelerating the inflammatory process[1]. Despite of the records, etiology and pathogenesis of IBD remain rather unclear. There are many studies over the past couple of years have led to great advanced in understanding the inflammatory bowel disease(IBD) and their underlying pathophysiologic mechanisms. From the current understanding, it is likely that chronic inflammation in IBD is due to aggressive cellular immune responses including increased serum concentrations of different cytokines. Therefore, targeted molecules can be specifically eliminated in their expression directly on the transcriptional level. Interesting therapeutic trials are expected against adhesion molecules and pro-inflammatory cytokines such as TNF-${\alpha}$. The future development of immune therapies in IBD therefore holds great promises for better treatment modalities of IBD but will also open important new insights into a further understanding of inflammation pathophysiology. Treatment of cytokine inhibitors such as Immunex(Enbrel) and J&J/Centocor(Remicade) which are mouse-derived monoclonal antibodies have been shown in several studies to modulate the symptoms of patients, however, theses TNF inhibitors also have an adverse effect immune-related problems and also are costly and must be administered by injection. Because of the eventual development of unwanted side effects, these two products are used in only a select patient population. The present study was performed to elucidate the ability of TNF-${\alpha}$ antibodies produced in sheep colostrums to neutralize TNF-${\alpha}$ action in a cell-based bioassay and in a small animal model of intestinal inflammation. In vitro study, inhibitory effect of anti-TNF-${\alpha}$ antibody from the sheep was determined by cell bioassay. The antibody from the sheep at 1 in 10,000 dilution was able to completely inhibit TNF-${\alpha}$ activity in the cell bioassay. The antibodies from the same sheep, but different milkings, exhibited some variability in inhibition of TNF-${\alpha}$ activity, but were all greater than the control sample. In vivo study, the degree of inflammation was severe to experiment, despite of the initial pilot trial, main trial 1 was unable to figure out of any effect of antibody to reduce the impact of PAF and LPS. Main rat trial 2 resulted no significant symptoms like characteristic acute diarrhea and weight loss of colitis. This study suggested that colostrums from sheep immunized against TNF-${\alpha}$ significantly inhibited TNF-${\alpha}$ bioactivity in the cell based assay. And the higher than anticipated variability in the two animal models precluded assessment of the ability of antibody to prevent TNF-${\alpha}$ induced intestinal damage in the intact animal. Further study will require to find out an alternative animal model, which is more acceptable to test anti-TNF-${\alpha}$ IgA therapy for reducing the impact of inflammation on gut dysfunction. And subsequent pre-clinical and clinical testing also need generation of more antibody as current supplies are low.

• Journal of Periodontal and Implant Science
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• v.29 no.3
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• pp.483-509
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• 1999

Biodegradable barrier membrane has been demonstrated to have guided bone regeneration capacity on the animal study. The purpose of this study is to evaluate the effects of cultured calvarial cell inoculated on the biodegradable barrier membrane for the regeneration of the artificial bone defect. In this experiment 35 Sprague-Dawley male rats(mean BW 150gm) were used. 30 rats were divided into 3 groups. In group I, defects were covered periosteum without membrane. In group II, defects were repaired using biodegradable barrier membrane. In group III, the defects were repaired using biodegradable barrier membrane seeded with cultured calvarial cell. Every surgical procedure were performed under the general anesthesia by using with intravenous injection of Pentobarbital sodium(30mg/Kg). After anesthesia, 5 rats were sacrificed by decapitation to obtain the calvaria for bone cell culture. Calvarial cells were cultured with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. The number of cell inoculated on the membrane were $1{\times}10^6$ Cells/ml. The membrane were inserted on the artificial bone defect after 3 days of culture. A single 3-mm diameter full-thickness artificial calvarial defect was made in each animal by using with bone trephine drill. After the every surgical intervention of animal, all of the animals were sacrificed at 1, 2, 3 weeks after surgery by using of perfusion technique. For obtaining histological section, tissues were fixed in 2.5% Glutaraldehyde (0.1M cacodylate buffer, pH 7.2) and Karnovsky's fixative solution, and decalcified with 0.1M disodium ethylene diaminetetraacetate for 3 weeks. Tissue embeding was performed in paraffin and cut parallel to the surface of calvaria. Section in 7${\mu}m$ thickness of tissue was done and stained with Hematoxylin-Eosin. All the specimens were observed under the light microscopy. The following results were obtained. 1 . During the whole period of experiment, fibrous connective tissue was revealed at 1week after surgery which meant rapid soft tissue recovery. The healing rate of defected area into new bone formation of the test group was observed more rapid tendency than other two groups. 2 . The sequence of healing rate of bone defected area was as follows ； test group, positive control, negative control group. 3 . During the experiment, an osteoclastic cell around preexisted bone was not found. New bone formation was originated from the periphery of the remaing bone wall, and gradually extended into central portion of the bone defect. 4 . The biodegradable barrier membrane was observed favorable biocompatibility during this experimental period without any other noticeable foreign body reaction. And mineralization in the newly formed osteoid tissue revealed relatively more rapid than other group since early stage of the healing process. Conclusively, the cultured bone cell inoculated onto the biodegradable barrier membrane may have an important role of regeneration of artificial bone defects of alveolar bone. This study thus demonstrates a tissue-engineering the approach to the repair of bone defects, which may have clinical applications in clinical fields of the dentistry including periodontics.

• Journal of Periodontal and Implant Science
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• v.24 no.2
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• pp.321-339
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• 1994

The cytokines released by osteoblasts induce bone resorption via the differentiation of osteoclast precursors. In this process, $interleukin-1{\beta}$($IL-1{\beta}$)-induced bone resorption is mediated by granulocyte macrophage-colony stimulation factor(GM-CSF), interleukin-6 (IL-6), and tumor necrosis factor ${\alpha}$($TNF-{\alpha}$) released from osteoblasts. Since these cytokines (GM-CSF, IL-6, $TNF-{\alpha}$) are produced by not only osteoblasts but also monocytes, and interleukin-10(I1-10) inhibits the secretion of these cytokines from monocytes, it may be speculated that IL 10 could modulate the production of GM-CSF, IL-6, and $TNF-{\alpha}$ by osteoblasts, then control $IL-1{\beta}-induced$ bone resorption. Therefore, the aims of the present study were to examine the effects of IL-10 on bone resorption. The sixten or seventeen-day pregnant ICR mice were injected with $^{45}Ca$ and sacrificed one day after injection. Then fetal mouse calvaria prelabeled with $^{45}Ca$ were dissected out. In order to confirm the degree of bone resorption, mouse calvaria were treated with Lipopolysaccharide(LPS), $TNF-{\alpha}$, $IL-1{\alpha}$, IL-8, $IL-1{\beta}$, and $IL-1{\alpha}$, Then, IL-10 and $interferon-{\gamma}$ ($IFN-{\gamma}$) were added to calvarial medium, in an attempt to evaluate the effect of $IL-1{\beta}-induced$ bone resorption. In addition, osteoclasts formation in bone marrow cell cultures, and the concentration of IL-6, $TNF-{\alpha}$, and GM-CSF produced from mouse calvarial cells were investigated in response to $IL-1{\beta}$ alone and simultaneously adding f $IL-1{\beta}$ and IL-10. The degree of bone resorption was expressed as the ratio of $^{45}Ca$ release(the treated/the control). The osteoclasts in bone marrow cultures were indentified by tartrate resistant acid phosphatase(TRAP) stain and the concentration of the cytokines was quantified using enzyme linked immunosorbent method. As results of these studies, bone resorption was induced by LPS(1 ng/ml ; the ratio of $^{45}Ca$ release, $1.14{\pm}0.07$). Also $IL-1{\beta}$(1 ng/ml), $IL-1{\alpha}$(1 ng/ml), and $TNF-{\alpha}$(1 ng/ml) resulted in bone resorption(the rations of $^{45}Ca$ release, $1.61{\pm}0.26$, $1.77{\pm}0.03$, $1.20{\pm}0.15$ respectively), but IL-8 did not(the ratio of $^{45}Ca$ release, $0.93{\pm}0.21$). The ratios of $^{45}Ca$ release in response to IL-10(400 ng/ml) and $IFN-{\gamma}$(100 ng/ml) were $1.24{\pm}0.12$ and $1.08{\pm}0.04$ respectively, hence these cytokines inhibited $IL-1{\beta}$(1 ng/ml)-induced bone resorption(the ratio of $^{45}Ca$ release $1.65{\pm}0.24$). While $IL-1{\beta}$(1 ng/ml) increased the number of TRAP positive multinulcleated cells in bone marrow cultures($20{\pm}11$), simultaneously adding $IL-1{\beta}$(1 ng/ml) and IL-10(400 ng/ml) decreased the number of these cells($2{\pm}2$). Nevertheless, IL-10(400 ng/ml) did not affect the IL-6, GM-CSF, and $TNF-{\alpha}$ secretion from $IL-1{\beta}$(1 ng/ml)-activated mouse calvarial cells. From the above results, it may be suggested that IL-10 inhibites $IL-1{\beta}-induced$ osteoclast differntiation and bone resorption. However, the inhibitory effect of IL-10 on the osteoclast formation seems to be mediated not by the reduction of IL-6, GM-CSF, and $TNF-{\alpha}$ production, but by other mechanisms.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.7
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• pp.839-845
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• 2009

Colorectal cancer is the third most common malignant neoplasm in the world. Much attention has been focused on reducing colon cancer risk through medical properties of natural compound that could act as anticarcinogens. In this study, we evaluated the antioxidant and antigenotoxic effects of Styela plicata (S. plicata) from in vitro experiments. S. plicata extracts showed antioxidant activity measured by TRAP assay and antigenotoxic effect in $200{\mu}M$ $H_2O_2$ induced DNA damage in human leukocytes. Especially, freeze-dried S. plicata extracted with methanol showed the highest level of TRAP (0.225 mM) and inhibition of DNA damage (66.8%). Additionally we observed the effect of S. plicata on the formation of aberrant crypt foci (ACF) induced by dimethylhydrazine (DMH) and DMH induced DNA damage (by comet assay) in male SD rats. The animals were divided into three groups and fed high-fat and low fiber diet (100 g lard+20 g cellulose/kg diet) without (normal control and DMH control) or with a 3% (w/w) of lyophilized S. plicata powder (DMH+S. plicata). One week after beginning the diets, rats were treated with DMH (30 mg/kg, s.c.) for 6 weeks except for normal control group, which was treated saline instead; dietary treatments were continued for the entire experiment. Nine weeks after DMH injection, administration of S. plicata resulted in reduction of ACF numbers, to 82.7% of the carcinogen control value ($7.67{\pm}2.04$ vs. $1.33{\pm}0.53$: p<0.01). S. plicata supplementation induced antigenotoxic effect on DMH-induced DNA damage in the blood cell (% tail intensity: $6.79{\pm}0.26$ vs. $6.13{\pm}0.22$). These data indicate that S. plicata extract has antigenotoxic and anticarcinogenic effects from in vitro experiments and S. plicata exerts a protective effect on the process of colon carcinogenesis, possibly by suppressing the DMH-induced DNA damage in blood cell and the development of preneoplastic lesions in colon.

• Clinical and Experimental Pediatrics
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• v.48 no.8
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• pp.813-819
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• 2005

Purpose : Medicolegal problems start when the patient asserts the mistake of doctor and doctor does not accept it. The purpose of this study is to assess the actual condition of medicolegal problems and to provide solutions of medicolegal problems in the pediatric field. Methods : There is not official statistical data about medicolegal problems in our country. We gathered data of legal insurance program of Korean Medical Association(KMA) and court cases and other fragmentary data. Results : Between 1981 and 1995, of total 2,338 cases reported to legal problem insurance program of KMA, most common ones were 748 cases of obstetrics and gynecology. Pediatric case was ranked at the 5th, 74 cases(3.1%). According to analysis of 41 medicolegal cases' after 1990, maltreatment of patient had the highest incidence of 14 cases, injection and medication were related to 12 cases, misdiagnosis was 9 cases, patient management were related to 4 cases, and others were 2 cases. The trial result of the medicolegal cases was that 31 cases were compensated, and 8 cases were defeated, and 2 cases were still in the process. Conclusion : The aspect of medical legal problem has the tendency of radicalism and systematization. This brings an economic destitution in the patient and gives damage to a doctor. In order to reduce medicolegal problem, doctor should offer a duty of explanation and efforts to his best to satisfy patient and endeavor to make an intimate doctor-patient relationship.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.2
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• pp.130-139
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• 2000

Serial basic tests were conducted for the determination of fundamental kinetics and for the actual application of kinetic parameter to food waste digestion with precise measurement of methane production under a thermophilic condition. The effects of food particle size, sodium ion concentration, and volatile solid (VS) loading rate on the anaerobic thermophilic food waste digestion process were investigated. Results of serial test for the determination of fundamental kinetic coefficients showed the value of k (maximum substrate utilization rate coefficient) and KS (half-saturation coefficient) as $0.24hr^{-1}$ and $700mg/{\ell}$, respectively, for non-inhibiting organic loading range. No inhibition effect was shown until $5g/{\ell}$ of sodium ion concentration was applied to a serum bottle reactor. However, the volume of methane gas was decreased gradually when the concentrations of more than $5g/{\ell}$ of sodium ion applied. All sizes of food waste particle showed the same constants (A : 0.45) but the maximum substrate utilization rate constant ($k_{HA}$) was inversely proportional to particle size. As an average particle size increased from 1.02 mm to 2.14 mm, $k_{HA}$ decreased from $0.0033hr^{-1}$ to $0.0015hr^{-1}$. The result reveals that particle size is one of the most important factors in anaerobic food waste digestion. There was no inhibition effect of sodium ion when VS loading rate was $30g/{\ell}$. And maximum injection concentration of VS loading rate was determined about $40g/{\ell}$.

• Applied Biological Chemistry
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• v.45 no.1
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• pp.11-17
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• 2002

Fermentation characteristics with/without nitrogen source and quality of the fruit distillate of Opuntia ficus-indica var. saboten were investigated during the manufacturing process of a Korean traditional liquor. As the fermentation period increased, acidity, brix degree, and alcohol concentration increased, whereas pH and contents of reducing sugar decreased. Acidity, pH, and brix degree were higher, whereas the content of reducing sugar lower, in the nitrogen source-added distillate than in the distillate without nitrogen source. The growth of yeast increased, while that of bacteria decreased; this trend was more prominent with the addition of a nitrogen source. Sojues, distilled from two types of mashes and diluted with $H_2O$ and tails of distillate into 22% alcohol concentration, showed pH $3.7{\sim}4.0$, acidity $0.02{\sim}0.10$, and $5.4{\sim}6.1$ $^{\circ}Brix$. Analysis through GC using direct injection methods revealed common volatile flavor compounds in sojues, including acetaldehyde, acetyl acetone, acetic acid ethyl ester, ethyl alcohol, 2-propyl alcohol, acetone, n-propyl alcohol, butanoic acid methyl ester, 2-phenyl ethanol, thymol, acetic acid phenyl ester, and vanillic aldehyde. As revealed through the sensory evaluation, no significant difference (p>0.05) in overall acceptability was shown among four experimental groups, while color and flavor showed significant differences(p<0.05).

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.23 no.2
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• pp.27-40
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• 2010

Background and Objective : Increasing interest in anti-aging and anti-wrinkling agents for the skin has triggered the recent outflow of researches and studies in this field. This study was designed to investigate the effects of bee venom on skin wrinkling and skin aging by testing the skin wrinkling, skin elasticity, trans-epidermal water loss (TEWL), free radical level, anti-oxidative agent level, and skin tissue after infusion of bee venom on hairless mouse. Materials and Methods : Fifteen hairless mice aged between 36~40 weeks were divided randomly into 3 Group; the Bee Venom Syringe Group, the Bee Venom Needle Group, and the control group. The Bee Venom Syringe Group were injected subcutaneously with bee venom (0.1cc in total) using an insulin syringe on three spots in the lumbar spine (one spot on the center and two spots 1~2cm to the side bilaterally). The Bee Venom Needle Group were pricked with bee venom-smeared acupuncture needles on three longitudinal spots in the lumbar spine each 1cm apart, after which the needles were removed 10 minutes later. The Control Group did not receive any form of intervention. All procedures took place thrice a week for four weeks, during which the mice were allowed free access to water and fodder. The mice were measured and compared in the weight, skin wrinkling scale, skin elasticity, and TEWL before and after the experiment. After the experiment, blood samples were taken to measure the free radical and anti-oxidative agent level, and the skin tissue was sliced for examination. Data was analyzed using the SPSS program (ver 12.0). The ANOVA analysis was used to compare and contrast the three groups, and t-test for paired samples was used to evaluate skin-wrinkling before and after experiment. The cut-off p-value of significance was set at p<0.05. Results : 1. Administration of bee venom did not cause serious weight loss or gain. 2. Compared to the control group, the Bee Venom Syringe Group and the Bee Venom Needle Group both showed a decrease in skin wrinkling scale after intervention. Especially, the Bee Venom Syringe Group showed a significant decrease (p<0.05). 3. Compared to the control group, the Bee Venom Syringe Group and the Bee Venom Needle Group both showed an increase in skin elasticity. Especially, the Bee Venom Syringe Group showed a significant increase (p<0.05). 4. No significant change in TEWL was found in the mice in all the three groups before and after experiment. 5. Free radical level was normal in all 15 mice in all the three groups, and anti-oxidative agent was not significantly different across the three groups. 6. The Bee Venom Syringe Group, the Bee Venom Needle Group, and the control group did not show any significant difference in the thickness of epidermis and dermis, infiltration of inflammatory cells, and skin wrinkling. The epidermis layer was relatively better preserved in the Bee Venom Syringe Group as compared to the Bee Venom Needle Group and the control group. Conclusion : Direct injection of bee venom on the hairless mouse using a syringe was found to improve wrinkling of the skin and increase skin elasticity but did not show effectiveness on skin dryness due to water loss. The bee venom appears to have suppressive effects on skin wrinkling, one of the symptoms of skin aging, through a process independent of suppression of free radicals or increase of anti-oxidative agent.