http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Heterologous Expression of Cholera Toxin B Subunit in Saccharomyces cerevisiae
임정구,진효상 한국생물공학회 2008 Biotechnology and Bioprocess Engineering Vol.13 No.5
The cholera toxin B subunit (CTB), which consists of five identical polypeptides and adopts a pentameric structure, has been shown to bind to the GM1-gangliosides at the cellular surface. Recombinant CTB has attracted much attention due to its non-toxicity and potential as a strong immunogenic antigen and immuno adjuvant for both system and mucosal immune re-sponses. In this study, CTB was expressed in Saccharomyces cerevisiae and the resulting recombinant CTB was exten-sively characterized. PCR and back-transformation into E. coli confirmed the presence of the CTB gene-containing plasmid in the transformants and northern analysis showed the presence of the CTB-specific transcript. Western blot analysis of the yeast-derived protein extract showed the presence of CTB with mobility similar to purified CTB from Vibrio cholerae suggest-ing that the expressed CTB assembled into the desired pentameric form. Quantitative ELISA revealed that the recombinant CTB comprised approximately 0.5~1.3% of the total cell-free extract. In addition, 0.5~2 mg of CTB protein per liter of cul-tured media was detected 1 day, at the earliest after cultivation. The GM1-ganglioside enzyme-linked immunosorbent assay (GM1-ELISA) confirmed that the yeast-derived CTB bound specifically to the GM1-ganglioside receptor, indicating that it re-tained its native function and pentameric form, which is required for binding to intestinal epithelial cell membrane glycolipid receptors. In addition to the development of a yeast-derived edible vaccine against cholera, this study regarding the expres-sion and assembly of recombinant CTB into biologically active oligomers in recombinant S. cerevisiae enables the efficient production of a GRAS microorganism-based adjuvant, as well as the development of carriers for foreign vaccine molecules.
임정구,권기선,Robin E. Dodge 한국항공운항학회 2010 한국항공운항학회지 Vol.18 No.1
Introduction : Head trauma is the main cause of death in aircraft crash. In a Michigan study of structurally survivable, fatal accidents, 80% of the fatally injured had received head trauma. We tried to develop a new helmet for passengers, and perform its efficiency test. Methods : An aircraft helmet requires an excellent protection against head trauma,lightness, and small volumes. In addition, it must be wearable, fire resistant, and non toxic when it is burning. We developed two new helmets made from silicone foam which met all theses requirements. One was thin (2.5cm), and the other was thick (6.3cm). These looked like a motorcycle helmet and had only a soft silicone as liner material without an outer hard shell. Therefore we can carry them easily inside aircrafts. The standard test for helmet is Snell’s drop test. It measures the impact acceleration of head shaped metal wearing helmet during we drop it at certain heights. Impact sites were total 5 sites (front,back, right, left and top) for each helmet. All these sites were impacted twice. Results : The thickness of impact sites varied from 2.5cm to 6.3cm. The impact acceleration of 2.5cm thickness site when it was dropped from 1.0 meter was 379g. But, that of 6.3cm thickness site when it was dropped from 1.5 meter was only 163g. Unfortunately,both helmets didn't meet the Snell Standard for motorcycle helmets. Discussion : If we add suitable outer hard shell, and change its thickness and design, the efficiency will be increased. A study indicated that helmet could reduce the risk of head trauma up to 85%. We made helmet for passengers in aircraft crash for the first time. If we improve its weak points, it will decrease the frequency of head trauma in aircraft craft.
임정구 대한의사협회 2012 대한의사협회지 Vol.55 No.7
Recent reports show that over 2 billion people are travelling via air every year, and the number of countries involved in space exploration is growing. Aerospace medicine, one of the specialty areas in preventive medicine, focuses on the clinical care, research, and operational support of the health, safety, and performance of crewmembers and passengers of air and space vehicles. Flight surgeons are military medical officers who play an important role in these tasks. The civilian equivalent of the flight surgeon is the aviation medical examiner (AME). Among the challenges that we encounter at high altitudes are a change in pressure, noise, spa-tial disorientation, and acceleration. We should also overcome microgravity and radiation in space. The common in-flight medical emergencies are abdominal pain, diarrhea, chest pain, coll-apse,asthma, diabetes, and allergic reactions. There is only one aerospace medical institute, the Aerospace Medical Center, in the Republic of Korea. The Aerospace Medical Association of Korea, established in 1989, continues to grow. In the near future, aerospace medicine will be an important part of preventive medicine in the Republic of Korea.