• BMB Reports
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• v.37 no.4
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• pp.387-393
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• 2004

The L-asparaginase (E. C. 3. 5. 1. 1) enzyme was purified to homogeneity from Pseudomonas aeruginosa 50071 cells that were grown on solid-state fermentation. Different purification steps (including ammonium sulfate fractionation followed by separation on Sephadex G-100 gel filtration and CM-Sephadex C50) were applied to the crude culture filtrate to obtain a pure enzyme preparation. The enzyme was purified 106-fold and showed a final specific activity of 1900 IU/mg with a 43% yield. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the purified enzyme revealed it was one peptide chain with $M_r$ of 160 kDa. A Lineweaver-Burk analysis showed a $K_m$ value of 0.147 mM and $V_{max}$ of 35.7 IU. The enzyme showed maximum activity at pH 9 when incubated at $37^{\circ}C$ for 30 min. The amino acid composition of the purified enzyme was also determined.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.150-155
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• 1992

- Some properties of an extracellular cytosine deaminase excreted from an isolate from soil samples were examined after 20~80%' ammonium sulfate fractionation. The enzyme catalyzed the conversion of cytosine and 5-fluorocytosine into uracil and 5-fluorouracil by substrate specificity, respectively. The optimum temperature and storage time on the stability of the enzvme preparation were below $50^{\circ}C$ keeping above 90% of the residual activity and near 4 days keeping above 80% of the residual one in Tris-HCI buffer. The maximum activity was also obtained at 8.0 in pH and 37'C in temperature. The pHs and temperatures for enzyme activity ranged from 8.0~8.5 and from 37~$45^{\circ}C$. respectively. The presence of $Ag^-,Hg^{2-}, Zn^{2-}, Cu^{2-}, Sn^{2-}, \; or\; Pb^{2-}$ in the reaction mixture resulted in the marked inhibition in enzyme activity, but 1 mM of $K^+, Fe^[3+}, Mg^{2+}, \; or \; Na^+$. slightly increased the activity. The enzyme preparation was heavily affected by most of inhibitors tested such as 1 mM of EIITA, NaCN and pentachlorophenol, and completely inactivated by p-CMB and TCA of 1 mM, or 10 mM.

• The Transactions of the Korea Information Processing Society
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• v.6 no.9
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• pp.2460-2469
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• 1999

Recently, appearing of various wireless telecommunications services, the competitive power of paging service is requested. In this paper, two-way paging earth station for satellite was proposed and designed to enhance the competitive power of cost and technique, and the link budget of this two-way paging networks using Koreas at was discussed. To reduce the cost of remote station, the antenna and HPA size of Hub and remote station were differently designed, and an idea of power allocations of inbound and outbound carriers was proposed and utilized in this link budget of two-way earth station for using satellite. The results of this link budget were follows. At the 0.043% time rate of rain, antenna size of Hub and remote station were 3.7m and 1.2m, the HPA size of Hub and remote station were 10.37W and 2.0W, and power allocations of outbound and inbound were 84% and 16% respectively. At the 0.02% time rate of rain, the antenna size of Hub and remote station were 3.7m and 1.8m and power allocations of outbound and inbound were 63% and 37% respectively.

• The Korean Journal of Physiology
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• v.14 no.1
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• pp.25-30
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• 1980

It has been well known that beta-adrenoceptor is responsible for the renin release stimulatory and alpha-adrenoceptor may be inhibitory. It has been observed accidently that alpha-adrenergic agonist can inhibit renin release by just changing the medium temperature in Vitro experiment in this laboratory. A series of experiments were performed to clarify this interesting phenomena in Vitro experiment. Rat renal slices were incubated in PSS medium under gas phase at $37^{\circ}C$. The following results were observed. 1) Isoproterenol and norepinephrine resulted in renin release stimulatory in dose-dependent by the concentrations of $10^{-9}$ to $10^{-5}\;M/L$ at $37^{\circ}C$. 2) Norepinephrine resulted in renin release inhibitory in dose dependent by the concentrations of $10^{-7}$ to $10^{-5}\;M/L$, and almost no effect by isoproterenol $10^{-6}\;M/L$ at $20^{\circ}C$. 3) Phenoxybenzamine pretreatment at $37^{\circ}C$ accentuated isoproterenol stimulatory effect at $37^{\circ}C$. 4) Phenoxybenzamine pretreatment at $20^{\circ}C$ attenuated isoproterenol stimulatory effect at $37^{\circ}C$. These data suggest that the renal adrenoceptor(s) related to renin release maybe a single entity, and can be interconverted different forms in certain conditions.

• Korean Journal of Materials Research
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• v.10 no.12
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• pp.799-806
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• 2000

Cu$_{6}$Sn$_{5}$-dispersed 63Sn-37Pb solder bumps of 760$\mu\textrm{m}$ size were fabricated on Au(0.5$\mu\textrm{m}$)/Ni(5$\mu\textrm{m}$)/Cu(27$\pm$20$\mu\textrm{m}$) BGA substrates by screen printing process, and their shear strength were characterized with variations of dwell time at reflow peak temperature and aging time at 15$0^{\circ}C$ . With dwell time of 30 seconds at reflow peak temperature, the solder bumps with Cu$_{6}$Sn$_{5}$ dispersion exhibited higher shear strength than the value of the 63Sn-37Pb solder bump. With increasing the dwell time longer than 60 seconds, however the shear strength of the Cu$_{6}$Sn$_{5}$-dispersed solder bumps became lower than that the 63Sn-37Pb solder bumps. The failure surface of the solder bumps could be divided into two legions of slow crack propagation and critical crack propagation. The shear strength of the solder bumps was inversely proportional to the slow crack propagation length, regardless of the dwell time at peak temperature, aging time at 150 $^{\circ}C$ and the volume fraction of Cu$_{6}$Sn$_{5}$ dispersion.> 5/ dispersion.

• Korean Journal of Microbiology
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• v.47 no.4
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• pp.289-294
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• 2011

We investigated the cold shock sensitivity of DEAD-box RNA helicase gene deleted strains of in Bacillus subtilis CU1065. To understand cold shock effects, cells were cultivated at $37^{\circ}C$ to log phase ($O.D_{600}$=0.5-0.6) and then temperature was shifted to $15^{\circ}C$. Cold shock slow down the growth rate of wild type and deleted strains of DEAD-box RNA helicase gene (ydbR, yfmL, yqfR, deaD). The growth rate of ydbR deleted strain is 5 times severely reduced compared to that of wild type strain (CU1065). But the growth rate of other three (yfmL, yqfR, deaD) deleted strains is nearly equal to the growth rate of wild type. Compared to $37^{\circ}C$, the amount of ydbR and yqfR mRNA transcripts are increased at the growth temperature of $15^{\circ}C$. On the other hands the mRNA transcripts of yfmL and deaD are not changed at both conditions of $37^{\circ}C$ and $15^{\circ}C$. Upon cold shock treatment ydbR mRNA transcript is clearly increased. After treatment of rifampicin (bacteria transcription inhibitor) the amount of ydbR mRNA was measured. Temperature shift from $37^{\circ}C$ to $15^{\circ}C$ and rifampicin treatment showed slowly decay of ydbR mRNA. But at $37^{\circ}C$ and rifampicin treatment ydbR mRNA is rapidly reduced. These results showed that cold shock induction of ydbR mRNA resulted from the stability of ydbR mRNA and not from the transcription induction of ydbR. In relation to these results, we found the cold box element of csp (cold shock protein gene) in 5' untranslated region of ydbR gene. Cold shock induction of ydbR is caused by the stability of ydbR mRNA like the stability of csp mRNA.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.67-74
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• 2018

Thermoelectric thin film modules were fabricated by electroplating p-type $Sb_2Te_3$and n-type $Bi_2Te_3$ thin film legs with the same thickness of $20{\mu}m$ and different diameters of $100{\mu}m$, $300{\mu}m$, and $500{\mu}m$, respectively. The output voltage and output power of thin film modules were measured and compared as a function of the leg diameter. The modules processed with thin film legs of $100{\mu}m$, $300{\mu}m$, and $500{\mu}m$-diameter exhibited open circuit voltages of 365 mV at ${\Delta}T=36.7K$, 142 mV at ${\Delta}T=37.5K$, and 53 mV at ${\Delta}T=36.1K$, respectively. Maximum output powers of $845{\mu}W$ at ${\Delta}T=36.7K$, $631{\mu}W$ at ${\Delta}T=37.5K$, and $276{\mu}W$ at ${\Delta}T=36.1K$ were obtained for the modules fabricated with the thin film legs of $100{\mu}m$, $300{\mu}m$, and $500{\mu}m$-diameter, respectively.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.6
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• pp.451-455
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• 2008

Purpose: Lymphoscintigraphy and sentinel node biopsy has become a standard method for detection of axillary lymph node metastasis in breast cancer patients, but the standard radiopharmaceutical was not prepared. About detection of axillary lymph node metastasis by lymphoscintigraphy and sentinel node biopsy in breast cancer patient, we compared the results of Tc-99m Tin-colloid and Tc-99m Phytate by subareolar injection. Materials and Methods: This study included 382 breast cancer patients who were performed operation during 2001-2008. Three hundred forty nine patients was injected 0.8ml of Tc-99m Tin-colloid (37-185 MBq) by subareolar injection. Thirty three patients was injected 0.8ml of Tc-99m Phytate (37-185 MBq). Lymphoscintigraphy was performed in supine position and sentinel node localization was performed by hand-held gamma probe in operation. Result: Among 349 patients by Tc-99m Tin-colloid, 312 cases (89.4%) localized the sentinel node by lymphoscintigraphy, 304 cases (87.1%) localized by gamma probe. Among 33 patients by Tc-99m Phytate, 32 cases (97.0%) localized by lymphoscintigraphy, 33 cases (100%) localized by gamma probe. Detection rate by lymphoscintigraphy and gamma probe was superior for Tc-99m Phytate compared to that with Tc-99m Tin-colloid, with a statistically significant difference. (p<0.05, p<0.05) Conclusion: Tc-99m Phytate is a better choice for localization of sentinel node than Tc-99m Tin-colloid in breast cancer patients.

• BMB Reports
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• v.37 no.2
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• pp.229-233
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• 2004

A haemagglutinating protein from the saline extracts of Kalanchoe crenata leaves, which agglutinate all human blood types, was purified to homogeneity by ion-exchange chromatography on a DEAE-Cellulose column followed by gel filtration on a Sephadex G-100 column. The purified protein showed one band, both in non-denaturing PAGE and SDS-PAGE. The $M_r$ that was determined by SDS-PAGE was 44,000 Da and that estimated from gel filtration was 47,000. Treatment of the haemagglutinating protein with 5 mM EDTA diminished the haemagglutinating activity to 50% of the original level. The addition of divalent cations, 10 mM $Mg^{2+}$, 10 mM $Mn^{2+}$, or 10 mM $Ba^{2+}$, totally restored and enhanced the activity. The protein showed maximum activity over the 3-7 pH range and was heat-resistant. It was also a glycoprotein containing about 1.5% carbohydrate.

• Journal of Life Science
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• v.8 no.4
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• pp.400-409
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• 1998

Formation of adduct was studied in benzo(a)pyrene(BP)- and doxorubicin(Dx)-treated human NC-37 cells and isolated nuclei. Major adducts formed were determined by fluorescence absorption spectrophotometery and DNA-lin-ked protein assay. When isolated nuclei were exposed to carcinogens BP and DMBA, and anticancer drugs m-AMSA, ellipticine and Dx, varying degrees of adduct formation occured between DNA-protein complex and these drugs. When the mixture was centrifuged 1.7 M sucrose solution, binding BP and DMBA appeared to be similar between the sediment and the supernatant. When the sediment was centrifuged again with 0.35% polymin-P, the amount of BP bound was 2-fold greater in the protein(1077$\pm$55cpm) than in DNA fraction (470$\pm$20cpm), whereas that of DMBA was 1.6-fold greater in the DNA than in protein fraction. In the case of m-AMSA, ellipticine and Dx, the amount of binding was slightly greater in supernatant than in sediment in centrifugation with 1.7 M sucrose, and more than 3 times greater in the DNA- than in protein- fraction in centrifugation with 0.35% polymin P. DNA fractions which associated with a subset of nonhistone chromosomal protein were isolated from NC-37 cells exposed to $^{3}$H-BP and $^{14}$C-Dx. They were separated into two distince components DNA-S and DNA-P by centrifugation with 2M Nacl chromatin extraction. The results indicated that the amount of $^{3}$H-BP bound was 6.0-fold greater in DNA-P as compared with DNA-S, while that of $^{14}$C-Dx binding appreaed to be 6.2-fold greater in DNA-S than in DNA-P fraction. When $^{3}$H-BP binding wasdetermined in the presence of cold Dx, the amount of binding was reduced only in the DNA-P fraction, indicating that the interaction between DNA and protein is decreased. Gene expression by these drugs, BP treated cells were increased to compare with nomal cells but reduced by treatment with BP-Dx. These results suggest that the protein moiety which tightly bound to DNA-P fraction may play an important role in the regulation of gene expression.