• Journal of the Korean Institute of Gas
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• v.2 no.2
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• pp.18-25
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• 1998

According to the requirements of ANSI B3l.8, the pipe thickness is determined with hoop stress resulted from internal pressure. And the other loads induced by soil, vehicle, thermal expansion, ground subsidence, etc shall be evaluated rationally. There are two ways of calculating stress of buried gas pipeline. The first is FEM. FEM can calculate the stress regardless of the complexity of pipeline shape and boundary conditions. But it needs high cost and long time. The second is the way to use equation. The reliable equations to calculate the stress of buried gas pipeline was developed and have been used in designing pipeline and evaluating pipeline safety, But these equation are very difficult to understand and use for non-specialist. For easy calculation of non-specialist, the new computer program to calculate stress of buried natural gas pipeline have been developed. The stress is calculated by the equations and extrapolation of the graph resulted from FEM. The full paper is consist of series I and II. In this paper, series I, the calculating equation of the program is explained in detail.

• Applied Microscopy
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• v.39 no.3
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• pp.253-260
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• 2009

GM-CSF is a multipotent growth factor, which also plays an important role during the process of wound healing. rrhGM-CSF was specifically produced from rice cell culture in our laboratory (Hanson Biotech Co., Ltd, Daejeon). The rrhGMCSF contains more oligosaccharide side chains than any other types of GM-CSF. This work was taken to evaluate the influence on wound healing of rrhGM-CSF in male golden hamsters. Full thickness skin defects of 9 mm in diameter were made in the back of hamsters, and 100 ${\mu}L$ ointment containing rrhGM-CSF 50 ${\mu}g/mL$ was applied. Control groups were given ointment without rrhGM-CSF. The wound sizes were relatively reduced and skin was well regenerated in the experimental group compared with the control group. Structurally, reepithelialization and architecture of the skin following injury were well accomplished in the experimental group. And also, positive reaction of PCNA of the skin following injury was more prominent in rrhGM-CSF containing ointment treatment group. Since this type of GM-CSF has highly glycosylated side chains, the effectiveness might be retain longer and stable, regarding acceleration of wound healing in the animal model. The present study has important implications for further development of the therapeutic manipulation of wound healing using rrhGM-CSF.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.126-136
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• 2009

Purpose: We evaluated the correlation of the anatomic parameters of the acromion those represent on the magnetic resonance image (MRI) of impingement syndrome. Materials and Methods: From June, 2004 to December, 2005, 71 cases were surgically proven to be impingement syndrome, and the anterior acromial hooking angle, the lateral acromial hooking angle (AAHA and LAHA) and the acromial hooking index (AHI: the sum of the AAHA and LAHA) were compared to 16 control cases. At the same period, 55 cases were surgically proven to be partial or full thickness rotator cuff tear, and age, gender and twelve anatomic parameters, including the acromial type, the acromial angle, the anterior covering, the acromial slope, the AAHA, the lateral acromial angle, the acromial torsional angle, the lateral acromial angulation, the LAHA, the lateral covering, the acromiohumeral distance and the AHI were assessed. Results: The AAHA and AHI were increased as impingement syndrome proceeded. The acromial type and acromial angle, and the AAHA, LAHA and AHI showed significant differences between the controls and the rotator cuff tear patients on univariant analysis. On multivariant analysis, gender was most strongly correlated with rotator cuff tear. Age, AAHA and the acromial angle showed similar correlation, respectively. Conclusion: The coronal acromial shape is correlated with rotator cuff tear, and it is important to correct the lateral acromial shape when performing acromioplasty.

• Clinics in Shoulder and Elbow
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• v.17 no.2
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• pp.64-67
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• 2014

Background: The purpose of this study was to determine whether in patients with rotator cuff tears a correlation exists between molecular changes and clinical parameters such as age, duration of symptom, range of motion, and tear size. Molecular changes of matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) were assessed by measuring messenger RNA (mRNA) levels of the two proteins. Methods: The rotator cuff tissue from was obtained from the edge of a torn tendon revealed after debridement by a motorized shaver. Using the sample of rotator cuff tissue, the reverse transcription polymerase chain reaction was performed to quantify MMP-2 and TIMP-2 mRNA expression. To determine whether mRNA levels and the clinical variables, such as age, defect size, range of motion (ROM) of shoulder, and duration of symptoms, show any correlation, Spearman's correlation coefficients were used to test for significant differences. Results: There was an inverse correlation between the mRNA levels of MMP-2 and TIMP-2 from the torn rotator cuff tendons regardless of the clinical variables. However, comparison of mRNA levels versus clinical parameters such as age, defect size, range of motion and duration of symptoms revealed a number of findings. We found a significant correlation between age and mRNA levels of MMP-2 from torn cuffs (r = 0.513, p = 0.021). Further, we found a significant correlation between defect size in the full thickness tears and mRNA levels of MMP-2 (r = 0.454, p = 0.045). Conversely, no significant association between mRNA levels of MMP-2 and ROM or duration of symptom was found. Conclusions: Our results suggest that both MMP-2 and TIMP-2 may be involved in the disease process of rotator cuff tears. Although the level of mRNA expression of MMP-2 and TMP-2 remain constant in torn rotator cuffs irrespective of the clinical variables, their levels may be influenced by age and defect size, which could account to change in tendon degradation and the healing process.

• Journal of radiological science and technology
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• v.20 no.2
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• pp.49-55
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• 1997

This study was carried out to investigate radiographical and operating conditions of X-ray units and exposure doses to patients during chest radiography, so that the results could provide basic data used for reducing the exposure dose and for providing the diagnostic information with better quality. The conditions and exposure doses of 100 X-ray units mainly used for chest radiography were examined and also 100 radiological technologists mainly handling those apparatus at 76 medical facilities in Pusan were surveyed using a questionnaire from October 1 to December 31 in 1995. The following results were obtained from the study : 1. It was found that most units were capable of taking a high tube voltage radiography by showing 67% of the units equipped with the maximum tube voltage of 150 kV, 94% with more than 500 mA for the rating capacity and 85% with the full wave type of a signal phase. 2. For actual chest radiographical conditions, however, 80% of the units were operated at $60{\sim}100\;kVp$ and only 14% at 100 kVp and over for the high tube voltage. 3. The average exposure time was less than 0.1 second, and eighty four percent of the units adapted the X-ray tube currents ranging from 200 to 300 mA, 80% the focus-film distances between 180 and 210 cm, and 63% the focus sizes of more than 2.0 mm. 4. Most units(98%) employed additional filters made of aluminum, 75% the thickness of filters less than 2.0 mm, and only 2 units the compound filters. 5. Ortho chromatic system was only adopted in 13% of screen film system for the units, and 73% used the grid ratio at 8 : 1 for the low tube voltage during chest radiography. 6. The average exposure dose of all X-ray units during chest radiography was $371\;{\mu}Sv$ with a difference of about 16 times between the minimum to the maximum, and $386\;{\mu}Sv$ both at hospitals and at health centers, followed by $380\;{\mu}Sv$ at general hospitals and $263\;{\mu}Sv$ at university hospitals without showing any statistically significant differences. In conclusion, since patients during chest radiography at medical facilities in Pusan exposed to high levels of radiation, it is recommended that appropriate added filters and grids necessary for the high tube voltage radiography and high-speed screen systems should be adopted and used as soon as possible in order to reduce exposure dose to the patients.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.576-584
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• 2011

Purpose: The shape and location, the amount of the wound and the characteristics of the remaining tissues are known to influence wound contraction. The previous studies using small animals have not been an appropriate model because the wound healing mechanisms and skin structures are different from those of the human. The purpose of this study is to evaluate wound contraction according to the shape and location of the wound using a $Micropig^{(R)}$. Methods: Four $Micropigs^{(R)}$ (Medikinetics, Pyeongtaek, Korea) that were 10 months of age weighed 25 kg were used. Full thickness skin defects were made by clearing all the tissues above the fascial layer in the shape of square, a regular triangle and a circle of 9 $cm^2$ each on the back around the spine. Eight wounds were created on the back of each pig, 50 mm apart from each other. The randomly chosen wound shapes included 11 squares, 11 regular triangles, and 10 circles. Wound dressing was done every other day with polyurethane foam. The wound size was measured using a Visitrak $Digital^{(R)}$ (Smith & Nephew, Hull, UK) on every other day after surgery from day 2 to day 28. A biopsy was performed on day 3, and 1, 2, 3 and 4 weeks to investigate the degree of acute and chronic inflammation, the number of microvesssel and myofibroblast density using H & E stain and immunohistochemistry. The wound contraction rate was calculated to figure out the differences among each of the shapes and the locations. Results: The ultimate shape of the circle wound was oval, and that of the regular triangle and square were stellate. The maximum contraction rate was obtained on 8 to 10 days for all the shapes, which corresponds with the immunohistochemical finding that myofibroblast increases in the earlier 2 weeks whereas it decreases in the later 2 weeks. Epithelialization was seen in the wound margin on day 7 and afterwards. The final wound contraction rates were highest for the regular triangle shapes; however, there were no statistically significant differences. The wound contraction rates by locations showed statistically significant differences. The wound in the cephalic area presented more contractions than that of the wounds in the caudal area. Conclusion: The location of a wound is more important factor than the wound shape in wound contraction.

• Archives of Plastic Surgery
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• v.37 no.6
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• pp.721-725
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• 2010

Purpose: The survival of composite graft is dependent on three steps, (1) plasmatic imbibitions, (2) inosculation, and (3) neovascularization. Among the many trials to increase the survival rate of composite graft, prostaglandin E1 (PGE1) has beneficial effects on the microcirculatory level with vasodilating, antithrombotic, anti-inflammatory and neoangiogenic properties. Lipo-PGE1 which is lipid microspheres containing PGE1 had developed to compensate the systemic and local side effects of PGE1. This study was proposed to determine whether Lipo-PGE1 administration enhanced the survival of composite graft through neovascularization quantitatively in a rabbit ear model. Methods: Fourteen New Zealand White Rabbits each weighing 3~4 kg were divided in two groups: (1) intravenous Lipo-PGE1 injection group and (2) control group. A $2{\times}1\;cm$ sized, full-thickness rectangular composite graft was harvested in each auricle. Then, the graft was reaaproximated in situ using a 5-0 nylon suture. For the experimental group, $3{\mu}g$/kg/day of Lipo-PGE1 ($5{\mu}g$/mL) was administered intravenously through the marginal vein of the ear for 14 days. The control group was received no pharmacologic treatment. On the 14th postoperative day, composite graft of the ear was harvested and immunochemistry staining used Monoclonal mouse anti-CD 31 antibody was performed. Neoangiogenesis was quantified by counting the vessels that showed luminal structures surrounded by the brown color-stained epithelium and counted from 10 random high-power fields (400x) by independent blinded observer. Statistical analysis (Wilcoxon Signed Ranks test for nonparametric data) was performed using SPSS v12.0, with values of p<0.05 considered significant. Results: The mean number of the microvessels was $15.48{\pm}8.65$ in the experimental group and $9.82{\pm}7.25$ in the control group (p=0.028). Conclusion: The use of Lipo-PGE1 facilitated the neoangiogenesis, resulted in the improvement of the survival rate of graft. On the basis of this results, we could support wider application of Lipo-PGE1 for more effective therapeutic angiogenesis and successful survival in various cases of composite graft in the human.

• Archives of Plastic Surgery
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• v.37 no.4
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• pp.323-328
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• 2010

Purpose: Adipose-derived stromal cells (ADSCs) are multipotent cells that have been found to promote wound healing through the process of angiogenesis and reepithelialization. Generally, it is well known that the antigenicity of ADSCs doesn't affect stem cell therapy. In this study, we investigated the effect of allogeneic ADSCs in the wound healing process by applying allogeneic ADSCs on the wound healing splint model of mice. Methods: Adipose tissue was harvested from the epididymal fat pads of BALB/c and C57BL/6 mice. Twenty four mice BALB/c were divided into three groups; control, isogeneic, and allogeneic groups. Two full thickness defects with 6 mm diameters were created on the back of BALB/c mice. $1{\times}10^6$ ADSCs from BALB/c mice were applied on the isogeneic group. In the allogeneic group, ADSCs from the C57BL/6 mice were applied. No cells were applied to the control group. The sizes of the wounds were evaluated in 3, 5, 7, 10, and 14 days after the wounds were applied, and tissues were harvested in 7 and 14 days for histological analysis. Results: Wound healing rates had showed significant increase in 10, and 14 days when the isogeneic group was compared to the control group, but the allogeneic group showed significantly decrease compared to the isogeneic group (p<0.05). Histological scores in the isogeneic group were significantly high, but significantly lower in the allogeneic group when compared to the isogeneic group in 2 weeks (p<0.05). In the isogeneic group, thick inflammatory cell infiltration with abundant capillaries were observed in 1 week, and thick epithelium with many large capillaries were observed in 2 weeks. Conclusion: When isogeneic ADSCs were applied to wounds, they presented a faster wound healing rate compared to controls and the allogeneic group. Unlike general stem cell therapy, these findings suggest that cell therapy targeted at enhancing wound healing may benefit from the use of ADSCs with identical antigenicity, as opposed to allogeneic or xenogenic ADSCs.

• Journal of Trauma and Injury
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• v.20 no.1
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• pp.52-56
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• 2007

Marjolin's ulcer is a rare and often-aggressive cutaneous malignancy that arises in previously traumatized or chronically inflamed skin, particularly after burns. We experienced two cases after burns. Case I involved a forty eight year-old man who had suffered from a flame burn at the parietal scalp area, where had been initially described three years earlier as a full-thickness wound including the pericranium. The man consulted us for a persistent ulcerative and infected wound on the burned lesion during the last 24 months, which turned out on the contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) to be the squamous cell carcinoma with involving the skull and the dura mater. Although the posterior auricular lymph node was enlarged on the ipsilateral side, recent positron emission tomography (PET) CT did not show any metastatic lesion. It was impossible for us to resect the intracranial involvement of the tumor radically, and the postoperative PET CT still showed a focal fluorodeoxyglucose (FDG) uptake around the wall of the superior sagittal sinus. We think that an aggressive combined approach is essential for treatment in early stages for a high success rate, before the intracranial structures are involved because there is no consensus on the treatment for advanced disease, and the results are generally poor. Case 1 also did not involve a radical resection because of the intracranial invasion to the wall of superior sagittal sinus and the possibility of damage to the major cortical veins. He received adjuvant radiotherapy and must be followed periodically. Case 2 involved an eighty six year-old women who suffered from a painful scalp ulcer lesion after flame burns three years earlier. Unlike case 1, neither tumor infiltration into the dura nor lymph node enlargement was observed on the contrast-enhanced computed tomography (CT), magnetic resonance imaging (MRI), or positron emission tomography (PET) CT. We did a radical resection of the tumor, including the involved bone, and a cranioplasty with bone cement.

• Journal of Animal Environmental Science
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• v.5 no.3
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• pp.157-170
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• 1999

This study was conducted to investigate the effects of Scoria, Quartz porphyry and Oak charcoal powder feeding by 1% level of concentrate on the fattening cross bred bulls(5/8 Korean Native Cattle, 2/8 Charolais, 1/8 Brahman germ plasma) Feeding trial was conducted with 4 treatment groups which were T1(Full feeding of concentrate and roughage for 12 months), T2(T1 and Scoria addition), T3(T1 and Quartz porphyry addition) and T4(Oak charcoal addition) for 360 days, consisting of 32 heads whose initially weights were about 299.7kg. The results obtained are summarized as follows; 1. During the over-all period, average daily gains by T3, T4, T2 and T1 were 1.024, 0.987, 0.977kg and 0.964, respectively, without a significant difference by treatments. 2. Concentrate intakes per body weight and TDN intakes required per unit of kilogram gain were lower in addition agent groups than in control, and in all the treatments feed efficiency was higher at early stage for 360 fattening day than at end stage. 3. Carcass weight, dressing percent, back-fat thickness and loin eye muscle area by treatments were 330.9 to 348.4kg(average 340.3kg), 55.2~56.2(average 55.8%), 0.41~0.55(average 0.46cm)and 76.0~80.9$\textrm{cm}^2$(average 77.6$\textrm{cm}^2$), respectively, and were improved in addition agent groups than in control. 4. Meat quality grade is higher in addition agent groups than in control, and heads of 1st grade by treatments was 3, 2, 1 and none in T4, T2, T3 and T1, respectively. 5. Incidence heads of diseases by treatment were not apparently different, but diseases of digestive system was decreased in addition agent groups than in control. 6. The nitrate nitrogen content of fattening bull dung which collected in rectum were 0.082~0.089% (average 0.084%), and the content in addition agent groups was smaller than in controll. 7. Income was higher in order of T4, T3, T2, and T1 and incomes of treatment groups were grater than that of control group by 21.4 to 33.5 percent. According to the above results it may be concluded that fattening bulls may be required to feed no more than 1% of Scoria, Quartz porphyry and Oak charcoal powder based on the concentrate feeding level during the fattening period(12 to 24 month of age) to produce high quality meat and increase income.