• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.3
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• pp.180-185
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• 2005

Cytosine deaminase (cytosine aminohydrolase, EC 3.5.4.1) stoichiometrically catalyzes the hydrolytic deamination of cytosine and 5-fluorocytosine to uracil and 5-fluorouracil, respectively. Amino acid residues located in or near the active sites of the intracellular cytosine deaminase from chromobacterium violaceum YK 391 were identified by chemical modification studies. The enzymic activity was completely inhibited by chemical modifiers, such as 1mM NBS, chloramine-T, $\rho-CMB,\;\rho-HMB$ and iodine, and was strongly inhibited by 1mM PMSF and pyridoxal 5'-phosphate. This chemical deactivation of the enzymic activity was reversed by a high concentration of cytosine. Furthermore, the deactivation of the enzymic activity by $\rho-CMB$ was also reversed by 1mM cysteine-HCI, DTT and 2-mercaptoethanol. These results suggested that cysteine, tryptophan and methionine residues might be located in or near the active sites of the enzyme, while serine and lysine were indirectly involved in the enzymic activity. The intracellular cytosine deaminase from C violaceum YK 391 was assumed to be a thiol enzyme.

• Biomolecules & Therapeutics
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• v.17 no.3
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• pp.305-310
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• 2009

The aim of this study was to determine if a meloxicam hydrogel could be administered in vivo via phonophoretic transdermal delivery using pulsed ultrasound by examining its anti-hyperalgesic effects in a rat carrageenan inflammation model. Carrageenan (1%) was injected into the plantar surface of the right hindpaw, and meloxicam hydrogel was administered via phonophoretic transdermal delivery. Changes in the mechanical and thermal hyperalgesia, as well as swelling, showed that phonophoretic delivery of meloxicam exhibited significantly better anti-hyperalgesic and anti-inflammatory effects than pulsed ultrasound. Topical and systemic application of meloxicam hydrogel using phonophoresis showed similar anti-hyperalgesic effects. These findings suggest that the transdermal administration of a meloxicam hydrogel using phonophoresis by pulsed ultrasound might be useful for treating acute inflammation.

• Korean Journal of Materials Research
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• v.24 no.12
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• pp.700-703
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• 2014

Calcium phosphate minerals are biologically important because of their application in the fields of orthopaedics and dentistry. Herein we have tried to synthesize calcium phosphate minerals from biowaste clam shells. A simple microwave method was used to synthesize a mixture of calcium phosphate minerals such as hydroxyapatite, tri-calcium phosphate, and monetite. The microwave induces vibration of the dipole ions in the reagent. The heating and rearrangement of ions and atoms occurs during the process. The phases obtained in the final powder were ascertained by X-ray diffraction; the morphology of each sample was checked using a scanning electron microscope. We were able to obtain a mixture of calcium phosphate minerals using the microwave method; the calcined powder showed a brick like morphology, which is different from the rod shape morphology of the hydroxyapatite obtained using the hydrothermal process.

• Journal of the Korean Society for Nondestructive Testing
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• v.31 no.5
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• pp.508-515
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• 2011

Bovine incisor was investigated using active infrared thermography(IRT) to visualize crack on bovine teeth. An artificial crack was carefully created in bovine incisor sample by compression load of universal tensile machine. While applying a sinusoidal heat wave to the cracked bovine incisor through halogen lamp, consecutive digital infrared images was captured from the sample surface at a frequency synchronized with heat excitation. Phase information of thermal image was calculated by four-point correlation method and processed to produce the phase image of bovine incisor. This phase image showed clearly the crack on the incisor, which was hardly detected in traditional passive thermography.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.957-963
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• 2001

Bacillus subtilis YL-1004 was isolated from soil for the development of agents to control dental caries. This strain produced an extracellular lytic enzyme that hydrolyzed the Streptococcus mutans cell wall. The lytic enzyme was purified to homogeneity by affinity chromatography and gel permeation chromatography to give a single band on SDS-PAGE and non-denaturing polyacrylamide gel electrophoresis. The molecular weight of the enzyme was deduced from SDS-PAGE and gel chromatography to be 38 kDa and the PI to be 4.3 from isoelectric focusing. Sirty $\%$ of its lytic activity remained after incubation at $50^{\circ}C$ for 30 min, and its optimal temperature was $37^{\circ}C$ . The enzyme showed its highest activity at pH 8.0 and was stable at pHs ranging from 4.0 to 9.0. Treatment with several modifiers showed that a cysteine residue was involved in the active site of the enzyme. This lytic enzyme from Bacillus subtilis YL-1004 exhibited specificity towards Streptococci and also showed autolytic activity on Bacillus subtilis YL-1004.

• Journal of environmental and Sanitary engineering
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• v.24 no.4
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• pp.39-48
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• 2009

This paper investigated an overview of awareness for fluoride in the young christian association. 30% of men and 70% of women knew well the prevention of caries for fluoride and water fluoridation program and showed of 90% in 20's, 10% in 30's and 0.00% in 40's. 54%-known people for fluoride had each 37% of men and 63% of woman, then 46%-unknown people for fluoride had each 56.52% of man and 43.48% of women. This showed women knew well awareness for fluoride than men. This showed high level above 50% awareness for fluoride as 54% of comprehension for fluoride and 50% of water fluoridation program. Awareness of fluoride of the subjects known for fluoride, prevention of caries, effects of tooth and water fluoridation program appeared above 50% level as 54%, 47%, 45% and 50%, individually. Thus, tooth management in christian showed high level. But, awareness for fluoride of women in third condition 'unknown for mottled tooth' showed each 38%, 34% and 37%. The mottled tooth from an excessive fluoride appeared low level awareness for fluoride of women. It suggested hard scientific contents made woman subjects unknown the effects of fluoride for tooth.

• The Journal of Advanced Prosthodontics
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• v.7 no.1
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• pp.32-38
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• 2015

PURPOSE. The aim of this study was to compare the durability and retention of 4 types of attachments placed over computer aided design/computer aided manufacturing (CAD/CAM) titanium bars when subjected to different pH conditions. MATERIALS AND METHODS. Four commercially available attachments were investigated: Hader Yellow, Hader Red, Ackerman Gold and Ackerman Stainless Steel. These attachments and Ackerman CAD/CAM titanium bars were placed in 2 vessels containing different artificial saliva solutions (pH 7/pH 4) at $37^{\circ}C$ for one month to simulate corrosion conditions, and they were then subjected to mechanical testing (5400 cycles of insertion and removal). RESULTS. The results revealed that there were significant differences in the average values of insertion/removal force due to the pH (F (1, 24)=9.207, P<.05) and the type of attachment (F (3, 24)=11.742, P<.05). CONCLUSION. More acidic pH values were found to have a negative influence on the retention capacity of the attachments.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.32-34
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• 2002

Over the past two decades there has been a tremendous growth in the number of synchrotron radiation facilities in the world and also in Japan. The high flux and brightness radiation which derive from the third generation low emittance rings provide an ideal source for many applications in the medical sciences. The application of synchrotron radiation to medical imaging started in the early 80's in U.S.A, followed by European countries such as Germany and Russia. In Japan, researchs on intravenous coronary angiography started in 1884 at the Institute for High Energy Phisics(KEK) in Tsukuba. At present, it is the only application of syncrotron radiation which is at the stage of human study. In '90s, newer techniques such as phase and refraction contrast imaging appeared which are at the in vitro or animal study stage. Various types of x-ray CT have also been developed for three-dimensional imaging of the subjects. The present status of medical applications of synchrotron radiation in Japan is reviewed.

• International Journal of Oral Biology
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• v.39 no.4
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• pp.187-192
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• 2014

Nonthermal atmospheric pressure plasma has attracted great interest for biomedical applications. The plasma consists of charged particles, radicals, and a strong electric field as the fourth state of matter. This study evaluated the change in the surface roughness after tooth bleaching by plasma in combination with a low concentration (15%) of carbamide peroxide, specifically whether the application of plasma produced detriments, such as demineralization and structural change, with the goal of efficient and safe tooth bleaching. After being combined with plasma and 15% carbamide peroxide, the hydroxyapatite surface was significantly smoother with a low roughness average value. Tooth bleaching with 15% carbamide peroxide alone produced an irregular surface and increased the surface roughness with high roughness average value. Tooth bleaching with plasma resulted in no significant variations in hydroxyapatite in terms of change in surface roughness and surface topography. The application of tooth bleaching with plasma is not deleterious to dental hard tissue, implicating it as a safe tooth bleaching technique.

• Journal of the Korean Society for Heat Treatment
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• v.15 no.2
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• pp.76-81
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• 2002

The melt-spun amorphous $Fe_{77-X}P_{13}C_4B_4Al_2Mo_X$(x=4~10) and $Fe_{82-X}P_XC_4B_4Al_2Mo_8$(x=9~15) alloys were found to exhibit a large supercooled liquid region(${\Delta}T_x$) exceeding 40 K before crystallization. The largest ${\Delta}T_x$ for the glassy alloys containing Mo reaches as large as 65 K for the $Fe_{69}P_{13}C_4B_4Al_2Mo_8$ alloy. The corrosion behavior of the amorphous $Fe_{77-X}P_{13}C_4B_4Al_2Mo_X$(x=4~15) and $Fe_(82-X)P_XC_4B_4Al_2Mo_8$ (x=9~17) alloys were examined by electrochemical measurements in 9M $H_2SO_4$ solution at 303 K. The addition of Mo(or P) for replacing some portion of Fe is effective in improving the corrosion resistance of the investigated Fe-based glassy alloys. They are spontaneously passivated and have a wide passive region with low passive current density.