• The Journal of Korean Academy of Prosthodontics
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• v.44 no.1
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• pp.51-62
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• 2006

Purpose: The purpose of this study was to evaluate the pattern and the magnitude of stress distribution in the supporting tissues surrounding three different types of implants(ITI, 3i. and Bicon implant system) Material and method: Photoelastic models were made with PL-2 resin(Measurements Group, Raleigh, USA) and three implants of each kind were placed in the mandibular posterior edentulous area distal to the canine. For non-splinted restorations, individual crowns were fabricated on three titanium abutments. For splinted restorations, 3-unit axed partial dentures were fabricated. Photoelastic stress analyses were carried out to measure the fringe order around the implant supporting structure under simulated loaded conditions(15 lb. 30 lb). Conclusion: The results were as follows; 1 Regardless of the implant design, stresses were increased in the apex region of loaded implant when non-splinted restorations were loaded. While relatively even stress distribution occurred with splinted restorations. Splinting was effective in the second implant. 2. Strain around Bicon implant were lower than those of other implants, which confirmed the splinting effect. The higher the load, the more the stress occurred in supporting tissue, which was most obvious in the Bicon system. 3. Stress distribution in the supporting tissue was favorable in the ITI system. while the other side of 3i system tended to concentrate the stress in some parts.

• The Journal of Korean Society for Radiation Therapy
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• v.8 no.1
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• pp.55-61
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• 1996

A radiation beam incident on irregular or sloping surface produces an inhomogeneity of absorbed dose. The use of a tissue compensator can partially correct this dose inhomogeneity. The tissue compensator should be made based on experimentally measured thickness ratio. The thickness ratio depends on beam energy, distance from the tissue compensator to the surface of patient, field size, treatment depth, tissue deficit and other factors. In this study, the thickness ratio was measured for various field size of $5cm{\times}5cm,\;10cm{\times}10cm,\;15cm{\times}15cm,\;20cm{\times}20cm$ for 4MV X-ray beams. The distance to the compensator from the X-ray target was fixed, 49cm, and measurement depth was 3, 5, 7, 9 cm. For each measurement depth, the tissue deficit was changed from 0 to(measurement depth-1)cm by 1cm increment. As a result, thickness ratio was decreased according to field size and tissue deficit was increased. Use of a representative thickness ratio for tissue compensator, there was $10\%$ difference of absorbed dose but use of a experimentally measured thickness ratio for tissue compensator, there was $2\%$ difference of absorbed dose. Therefore, it can be concluded that the tissue compensator made by experimentally measured thickness ratio can produce good distribution with acceptable inhomogeneity and such tissue compensator can be effectively applied to clinical radiotherapy.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.375-379
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• 1997

Pulsed Er:YAG and $CO_2$ lasers induced temperature rise of tissue are studied using axisymmetric, two-dimensional, and transient Pennes' bio-heat equation or the implications of skin resurfacing. Model results indicate that Er:YAG laser induced temperature has much higher but more shallow distribution in tissue than that of the $CO_2$ laser because of its higher absorption coefficient. The increase of repetition rate does not affect the temperature rise too much because these laser modalities have much shorter heat diffusion time than the temporal length of each off-pulse. This model works as a tool to understand the photothermal effect in the laser-tissue interaction.

• Journal of Photoscience
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• v.5 no.1
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• pp.39-43
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• 1998

Pulsed Er: YAG and CO$_2$ lasers induced temperature rise of tissue is studied using axisymmetric, two-dimensional, and transient Pennes bio-heat equation for elucidating the implications of skin resurfacing. Modeling indicates that Er:YAG laser induced temperature has much higher but more shallow distribution in tissue than that of the CO$_2$ laser because of much higher absorption coefficient. The increase of repetition rate does not much affect on temperature rise because these laser modalities have much shorter heat diffusion time than the temporal length of each off-pulse. This model works as a tool to understand the photothermal effect in the laser-tissue interaction.

• The Journal of the Korean bone and joint tumor society
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• v.9 no.1
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• pp.69-76
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• 2003

Purpose: This study was designed to provide the data base for the diagnosis and treatment of the foot tumor by investigation of the clinical and pathological characteristics and distribution of the foot tumor. Materials and Methods: 142 foot tumors of 141 patients were studied. All patients were diagnosed with surgical biopsy. We investigated clinical and pathological characteristics and epidemiologic distribution of the foot tumor by reviewing the medical records and imaging materials. The location of the tumors were classified with zone of Kirby et al. Results: 75 patients were female and 66 were male. The average age of the patients was 33.2 years old. Benign soft tissue tumors were the most as 68 cases, and followed by 57 benign bone tumors, 12 malignant soft tissue tumors and 5 malignant bone tumors. Ganglia were the most in benign soft tissue tumors as 36 cases, subungual exostoses in benign bone tumors as 18, squamous cell carcinomas in malignant soft tissue tumors as 7, and metastatic lung cancers in malignant bone tumors as 2. The rate of pain complaints was the highest in malignant bone tumors, the duration of symptom was longest in benign soft tissue tumors, and the size of the tumor was the biggest in malignant bone tumors. Neurological symptoms were found in only 3 benign soft tissue tumors. For the zonal distribution, zone 5 was the most in 59 cases and zone 4 was the least as 10. The most numbers of the benign bone tumors located in zone 5, of benign soft tissue tumors in zone 1, of malignant bone tumors in zone 1 and 2, and of malignant soft tissue tumors in zone 5. The methods of surgical treatment included intralesional or marginal resection, curettage with or without bone graft, toe amputation, below knee amputation and limb salvage. Conclusion: The tumors of the foot were rare and various, and mostly benign (88%), but we can do proper treatment of those tumors without excluding malignant tumors by considering the age of patients, pain, duration of symptom, size of the tumors, and zonal distribution.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1577-1582
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• 2006

Cartilage tissue engineering has emerged as an alternative approach for reconstruction or repair of injured cartilage tissues. In this study, rabbit chondrocytes were cultured in a three-dimensional environment to fabricate a new cartilaginous tissue with the application of tissue engineering strategies based on biodegradable PLGA microspheres. Chondrocytes were seeded on PLGA microspheres and cultured on a rocking platform for 5 weeks. The PLGA microspheres provided more surface area to adhere chondrocytes compared with PLGA sponge scaffolds. The novel system facilitated uniform distribution of the cells on the whole of the PLGA microspheres, thus forming a new cartilaginous construct at 4 weeks of culture. The histological and immunohistochemical analyses verified that the number of chondrocytes and the amount of extracellular matrix components such as proteoglycans and type II collagen were significantly greater on the PLGA microspheres constructs as compared with those on the PLGA sponge scaffolds. Therefore, PLGA microspheres enhanced the function of chondrocytes compared with PLGA sponge scaffolds, and thus might be useful for formation of cartilage tissue in vitro.

• Applied Microscopy
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• v.24 no.4
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• pp.41-51
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• 1994

The topology of the enzyme has been investigated by biochemical studies including chemical labeling and cross linking. Thirteen subunits(polypeptides) of the cytochrome-c-oxidase have localistic characteristics of existing in the matrix side or cytoplasmic side in the mitochondria. In order to observe the distribution of the enzyme subunit on the mitochondria membrane, immunogold-labeling methods were employed. Antibody was obtained from the serum of immunized rabbit with enzyme subunit antigen which was obtained from cytochrome-c-oxidase of the beef heart muscle mitochondria. Beef heart muscle tissue as a tissue antigen was stained with immunized rabbit IgG and protein A gold complex. Electron microscopy has identified the existance of cytochrome-c-oxidase subunit $Mt_I,\;Mt_{II}\;and\;Mt_{III}$ on the membrane of cristae and outer chamber of mitochondria and the subunit $C_{IV}$ on the membrane of cristae and matrix of mitochondria. Particularly, the subunit $C_{IV}$ was also observed to exist in the sarcoplasm of muscle tissue.

• Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.291-301
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• 2013

The genomic organization, tissue distribution, and developmental expression of two paralogous GAPDH isoforms were characterized in the mud loach Misgurnus mizolepis (Cypriniformes). The mud loach gapdh isoform genes (mlgapdh-1 and mlgapdh-2) had different exon-intron organizations: 12 exons in mlgapdh-1 (spanning to 4.88 kb) and 11 in mlgapdh-2 (11.78 kb), including a non-translated exon 1 in each isoform. Southern blot hybridization suggested that the mud loach might possess the two copies of mlgapdh-1 and a single copy of mlgapdh-2. The mlgapdh-1 transcript levels are high in tissues requiring high energy flow, such as skeletal muscle and heart, whereas mlgapdh-2 is expressed abundantly in the brain. Both isoforms are differentially regulated during embryonic and larval development, during which their expression is upregulated with the progress of development. Lipopolysaccharide challenge preferentially induced mlgapdh-2 transcripts in the liver. Therefore, the two isoforms have diversified functionally; mlgapdh-1 is associated more closely with energy metabolism, while mlgapdh-2 is related more to stress/immune responses, in the mud loach.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.19-30
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• 1982

This study was performed to elucidate the histopathologic distribution of immunoglobulins, particularly IgA, IgG and IgM in the periapical lesions, including 22 periapical granulomas and 18 periapical cysts. The immunoperoxidase staining method using reagents manufactured and supplied by Danish DAKO company was employed in this study. In comparison with the immunohistochemical methods, this method was proved to be reliable and convinient one to detect immunoglobulins in the tissue. The following results were obtained: 1. In the 22 periapical granulomas, IgG was found in 20 cases (90.9%), IgA in 16 cases (72.7%) and IgM in 19 cases (86.3%). 2. In the 18 periapical cysts, IgG was found in 16 cases (88.8%), IgA in 13 cases (72.2%) and IgM in 15 cases (83.3%). 3. The distribution of immunoglobulins both in periapical granulomas and periapical cysts was in great diversity according to the lesion and area. 4. More immunoglobulins were found in the exudative area with moderate or severe infiltrations of plasma cells and lymphocytes and less concentration of immunoglobulins were seen in the area with leukocytes infiltration and tissue destruction. 5. The area with collagenolysis and reparative activity contained more abundant IgG and IgM than IgA in periapical granulomas. 6. IgG was dominant in the granulomatous connective tissue and immunoglobulins were not easily found in the fibrous capsule in periapical cysts.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.57-63
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• 1997

Animal and clinical investigations have shown that fluoroquinolones, new quinolone antibacterial agents (NQs), are well absorbed across the intestinal tract, with a bioavailability of 60-90% after oral administration. Although some types of carrier-mediated intestinal transport mechanisms have been reported for enoxacin (ENX), ofloxacin (OFLX) and sparfloxacin (SPFX), recent results using a human intestinal epithelial cell line, Caco-2, indicated a passive or nonsaturable transport of SPFX, one of the most hydrophobic NQs. The mechanism underlying the intestinal absorption of NQs is still largely unknown. The distribution of NQs into peripheral tissues including erythrocytes is very rapid and their tissue-to-plasma concentration ratios (Kp) are considerably larger than those of inulin (an extracellular fluid space marker), in spite of almost complete ionization of NQs at the physiological pH. Our findings suggest that OFLX and lomefloxacin (LFLX) are taken up by rat erythrocytes via a transport system common to that of a water-soluble vitamin, nicotinic acid.