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Characterization and Distribution of Glycoconjugates in Human Pulmonary Tubercles by Lectin Histochemistry (폐결핵 결절에서 복합당질의 분포에 관한 Lectin 조직화학적 연구)

  • Yoon, Sik;Kim, Ji-Hong;Shin, Cheol-Shik;Jeong, Suk;Son, Mal-Hyun;Song, Sun-Dae;Kim, Jin-Jeong
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.3
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    • pp.248-261
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    • 1994
  • Background: Lectins are proteins or glycoproteins of non-immune origin that recognize a specific sequence of sugar residues. The availability of a large number of lectins has provided the capacity to identify selectively glycoconjugates possessing distinctive chemical structure in diverse sites of highly specialized biological activity. The purpose of the present study was to investigate the lectin binding patterns of various components in human pulmonary tubercles. Method: Biopsy specimens of tuberculous lung were obtained from male adult patients who underwent a surgical resection for severe pulmonary tuberculosis. The specimens were processed and stained with 13 kinds of biotinylated lectins according to some modification of Hsu and Raine's methods. Results: 1) In the caseous necrotic lesions, BS $I-B_4$ showed negative reaction and BS I were also negative except some irregularly-shaped cells located in the marginal zone. All other lectins, however, showed a positive reaction with various binding patterns. 2) The epithelioid cells were broadly divided into three groups according to the reaction patterns in the cytoplasms and cell membranes. 3) WGA, ECL, PHA-L, PHA-E and LCA showed strong staining in the lymphocytes. 4) SBA showed a different binding patterns between the endothelial layers located in the region beyond the fibrous layers and those located within the fibrous layers. 5) PNA showed a positive reaction in the outer 1/3 to 1/2 of the fibrous layer, but showed no staining in the inner 1/2 to 2/3 of the fibrous layers. Conclusion: The present lectin histochemical study provided a useful information to assess the characterization and distribution of various glycoconjugates in each constituent of human pulmonary tubercles. The results demonstrate structural differences in the glycoconjugate composition of various components of the tubercles and reveal changes in glycosylation in the components during soft tubercle formation. This study provides a new data useful for the studies on the pathogenesis and pathology of human pulmonary tubercles.

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Repeated Pulmonary Metastasectomy in Patients with Osteosarcoma (골육종 환자의 반복적 폐전이 절제술)

  • Lee, Jin-Gu;Shin, Kyoo-Ho;Park, In-Kyu;Chung, Kyung-Young;Song, Seung-Jun;Kim, Dae-Joon
    • Journal of Chest Surgery
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    • v.40 no.9
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    • pp.607-612
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    • 2007
  • Background: Surgical resection is a standard treatment for pulmonary metastases in patients with osteosarcoma, but the role of performing repeated resections is not clear. This study was designed to clarify the feasibility of performing a repeated pulmonary metastasectomy and the prognostic factors for pulmonary metastases in patients with osteosarcoma. Material and Method: Between January 1990 and July 2005, 62 patients with osteosarcoma were diagnosed with pulmonary metastases and 36 patients underwent pulmonary resection. We reviewed the patients retrospectively. Result: The total number of pulmonary metastasectomies was 62 in 30 patients. Among 36 patients, 18 had a second metastasectomy, 7 had a third metastasectomy, and one patient had a fourth metastasectomy. There was no distinctive difference between the first and second metastatectomy in terms of median survival time, and the 3-year and 5-year survival rate (first resection: 20.5 months, 32.0% and 29,4%; second resection: 11.3 months, 34.9% and 34.%). However, the median survival time (7.1 months) was shorter in patients with a third metastatectomy than in patients with one metastatectomy (p=0.01). In long-term survivors, the number of female patients, patients with a disease free time longer than 12 months, patients with a single metastasis and patients with anatomic resection was larger when compared to non-long term survivors, but showed no statistical significance. Conclusion: Repeated pulmonary metastasectomy is expected to prolong survival time in patients with osteosarcoma, and is expected to increase long-term survival in selected cases. Further studies with a large number of patients are necessary.

Recent research activities on hybrid rocket in Japan

  • Harunori, Nagata
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.04a
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    • pp.1-2
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    • 2011
  • Hybrid rockets have lately attracted attention as a strong candidate of small, low cost, safe and reliable launch vehicles. A significant topic is that the first commercially sponsored space ship, SpaceShipOne vehicle chose a hybrid rocket. The main factors for the choice were safety of operation, system cost, quick turnaround, and thrust termination. In Japan, five universities including Hokkaido University and three private companies organized "Hybrid Rocket Research Group" from 1998 to 2002. Their main purpose was to downsize the cost and scale of rocket experiments. In 2002, UNISEC (University Space Engineering Consortium) and HASTIC (Hokkaido Aerospace Science and Technology Incubation Center) took over the educational and R&D rocket activities respectively and the research group dissolved. In 2008, JAXA/ISAS and eleven universities formed "Hybrid Rocket Research Working Group" as a subcommittee of the Steering Committee for Space Engineering in ISAS. Their goal is to demonstrate technical feasibility of lowcost and high frequency launches of nano/micro satellites into sun-synchronous orbits. Hybrid rockets use a combination of solid and liquid propellants. Usually the fuel is in a solid phase. A serious problem of hybrid rockets is the low regression rate of the solid fuel. In single port hybrids the low regression rate below 1 mm/s causes large L/D exceeding a hundred and small fuel loading ratio falling below 0.3. Multi-port hybrids are a typical solution to solve this problem. However, this solution is not the mainstream in Japan. Another approach is to use high regression rate fuels. For example, a fuel regression rate of 4 mm/s decreases L/D to around 10 and increases the loading ratio to around 0.75. Liquefying fuels such as paraffins are strong candidates for high regression fuels and subject of active research in Japan too. Nakagawa et al. in Tokai University employed EVA (Ethylene Vinyl Acetate) to modify viscosity of paraffin based fuels and investigated the effect of viscosity on regression rates. Wada et al. in Akita University employed LTP (Low melting ThermoPlastic) as another candidate of liquefying fuels and demonstrated high regression rates comparable to paraffin fuels. Hori et al. in JAXA/ISAS employed glycidylazide-poly(ethylene glycol) (GAP-PEG) copolymers as high regression rate fuels and modified the combustion characteristics by changing the PEG mixing ratio. Regression rate improvement by changing internal ballistics is another stream of research. The author proposed a new fuel configuration named "CAMUI" in 1998. CAMUI comes from an abbreviation of "cascaded multistage impinging-jet" meaning the distinctive flow field. A CAMUI type fuel grain consists of several cylindrical fuel blocks with two ports in axial direction. The port alignment shifts 90 degrees with each other to make jets out of ports impinge on the upstream end face of the downstream fuel block, resulting in intense heat transfer to the fuel. Yuasa et al. in Tokyo Metropolitan University employed swirling injection method and improved regression rates more than three times higher. However, regression rate distribution along the axis is not uniform due to the decay of the swirl strength. Aso et al. in Kyushu University employed multi-swirl injection to solve this problem. Combinations of swirling injection and paraffin based fuel have been tried and some results show very high regression rates exceeding ten times of conventional one. High fuel regression rates by new fuel, new internal ballistics, or combination of them require faster fuel-oxidizer mixing to maintain combustion efficiency. Nakagawa et al. succeeded to improve combustion efficiency of a paraffin-based fuel from 77% to 96% by a baffle plate. Another effective approach some researchers are trying is to use an aft-chamber to increase residence time. Better understanding of the new flow fields is necessary to reveal basic mechanisms of regression enhancement. Yuasa et al. visualized the combustion field in a swirling injection type motor. Nakagawa et al. observed boundary layer combustion of wax-based fuels. To understand detailed flow structures in swirling flow type hybrids, Sawada et al. (Tohoku Univ.), Teramoto et al. (Univ. of Tokyo), Shimada et al. (ISAS), and Tsuboi et al. (Kyushu Inst. Tech.) are trying to simulate the flow field numerically. Main challenges are turbulent reaction, stiffness due to low Mach number flow, fuel regression model, and other non-steady phenomena. Oshima et al. in Hokkaido University simulated CAMUI type flow fields and discussed correspondence relation between regression distribution of a burning surface and the vortex structure over the surface.

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