• Journal of Embryo Transfer
• /
• v.18 no.2
• /
• pp.85-90
• /
• 2003

This study examined the viability of canine oocytes following storage at 4 or 38$^{\circ}C$ for 5 h. Cumulus intact oocytes were collected from domestic dog following ovariohysterectomy at local veterinary clinics. In Exp I, the oocytes that collected from ovary transport different temperatures (4 or 38$^{\circ}C$) for 5 h, were cultured for (24 or 48 h). Survivability of oocytes judged by morphological appearance and PI (propidium iodide) staining. The survival rates at 4$^{\circ}C$ ovary transport group showed significantly lower than control group (0%; 0/129 vs. 72.9%; 129/177) 48 h after culture (P<0.05). In Exp II, to assess nuclear maturation of control group oocytes (ovary transported at 38$^{\circ}C$) after in vitro cultured for 24, 48 or 96 h. After 24 h and 48 h of culture, the metaphase I to metaphase II stages (MI to MII) was 8.3% (6/72) and 8.9% (9/101), and which was not increased at 96h (9.5%; 8/84). These results show that canine oocytes remarkably sensitive to low temperature and the percentage of oocytes reaching MI to MII did not increase 96 h after culture.

• Bulletin of the Korean Chemical Society
• /
• v.25 no.4
• /
• pp.549-552
• /
• 2004

A sensitive, selective and rapid method has been developed for the determination of mercury based on the rapid reaction of mercury(II) with p-sulfobenzylidenethiorhodanine (SBDTR) and the solid phase extraction of the colored chelate with $C_{18}$ disks. In the presence of pH 3.5 sodium acetate-acetic acid buffer solution and Emulsifier-OP medium, SBDTR reacts with mercury(II) to form a red chelate of a molar ratio 1 : 2 (mercury to SBDTR). This chelate was prconcentrated by solid phase extraction with $C_{18}$ disks. An enrichment factor of 50 was achieved. The molar absorptivity of the chelate is $1.28{\times}10^5 L{\cdot}mol^{-1}{\cdot}cm^{-1}$ at 545 nm in measured solution. Beer's law is obeyed in the range of 0.01-3 ${\mu}$g/mL. The relative standard deviation for eleven replicates sample of 0.01 ${\mu}$g/mL is 1.65%. This method was applied to the determination of mercury in tobacco and tobacco additive with good results.

• Journal of Microbiology and Biotechnology
• /
• v.5 no.2
• /
• pp.80-86
• /
• 1995

The bacterial strain WC-17 able to produce chitinase was isolated from soil using an enrichment technique. The isolated strain was identified as Acinetobacter sp. judging by their morphological and physiological characterisitics. The optimal culture conditions for the production of chitinase of Acinetobacter sp. WC -17 are 1.5% colloidal chitin and 1 % tryptone at $30^{\circ}C$ with pH 6.5. Since the enzyme was rapidly produced in a culture supplied with chitin, glucose, or N-acetylglucosamine but not with other polymers and monosaccharide, the enzyme was considered to be an inducible enzyme. Notably N- acetylglucosamine and glucose were found to be effective inducers at low concentrations but repressors at excessive concentrations. The cultural supernatant of Acinetobacter sp. WC-17 inhibited the growth of phytopathogenic fungi such as P.oryzae, R.solani, and F.solani. Among the phytopathogenic fungi tested, P.oryzae was the most sensitive. The conventional agar plate (PDA containing 1 % colloidal chitin) method also produced the same result.

• The Korean Journal of Ecology
• /
• v.19 no.3
• /
• pp.201-207
• /
• 1996

Selection of Al tolerant woody plants, and possibility of reforestation with the Al tolerant plants in soil conditions with different Al content, topography and slope exposures were studied on the slopes around Yeocheon Industrial Complex. Root growth in length of plants grown in 1/2 Steinberg solution decreased with increased Al concentrations of the solution. Relative root length showed that Paulownia coreana, Celtis sinensis and Firmiana simplex were sensitive to $500\muM$ Al, Pinus koraiensis, Alnus japonica and Ligustrum japonicum were intermediate, and Pinus rigida, P. densiflora and P. thunbergii were tolerant to $1, 000\muM$ Al. Coniferous plants appeared to be more tolerant to Al than deciduous ones. Soil pH was 4.2 and Al content was 509 ppm in average around the Yeocheon industrial complex. Al content and soil acidity were more deteriorated on the foothill and slope facing to the pollution source from the industrial complex than on the ridge and opposite slope.

• The Journal of Korean Academy of Prosthodontics
• /
• v.24 no.1
• /
• pp.91-103
• /
• 1986

Using imprint cultures and epithelial smears, the density and prevalence of colonization of oral mucosal sites and denture surfaces by Candida albicans has been determined in 28 healthy dentate subjects and 20 denture wearers. With questionnaire, oral and denture examination, the relationship between the carrier rates and several factors; DMFT, oral hygiene index, salivary pH & denture plaque score were studied. But these factors have not significant relationship to the carrier rates. Imprint culture appears to be sensitive technique for detecting candidal carriers and be useful for distinguishing between the healthy carrier state and candidal infection. Cigarette smokers had a significantly increased carrier state (P<0.05) compared with nonsmoker in male dentate subjects. Female were more frequent carriers than male in dentate and denture group, but these differences were not significant. In denture wearers, there was a higher density and frequency of candidal colonization of all mucosal sites sampled, compared with that of healthy dentate group especially anterior palate and posterior palate showed highly significant differences in frequency of candidal colonization (P<0.05). The distribution of Candida albicans is not uniform throughout the mouth. The tongue in the healthy dentate subjects and the impression surfaces of upper dentures are the primary oral reservoirs for the fungus. Overnight wearing of dentures was associated with increased density and frequency of candidal colonization and density.

• Biomolecules & Therapeutics
• /
• v.3 no.4
• /
• pp.256-259
• /
• 1995

Antinociceptive and desensitizing effects of systemically administered capsaicinoids (capsaicin and KR25018) were investigated in guinea pig. Nociceptive sensitivity to chemical stimulus was examined to test sensory function, and the content of substance P-like immunorractivity (SP-LI) in bronchi was determined as a peripheral marker of capsaicin-sensitive primary afferent neurons. Guinea pigs were pretreated s.c. with several doses of capsaicin (1,2.5,5, 10 mg/kg) or KR25018 (1, 2.5, 5, 10 mg/kg) one week prior to the experiments. Frequency of eye wiping was significantly decreased by capsaicin and KR25018 in a pretreatment dosedependent manner. In capsaicin- or KR25018-pretreated guinea pigs, there was a significant loss of SP-LI in bronchial tissue extracts. In summary, a newly synthesized capsaicin analogue H725018 exhibited antinociceptive effect against chemical stimulus in guinea pig, with comparable potency to capsaicin. This desensitizing activity of capsaicin or KR25018 might be related to the loss of SP-LI in peripheral afferent nerves.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.8
• /
• pp.663-672
• /
• 2009

In this studies, the adsorption test using Chlorella pyrenoidosa was conducted to examine the effect of Pb adsorption according to various immobilized methods such as Ca-alginate, K-carrageenan, and Polyacrylamide. From the results, the duration to need to reach adsorption equilibrium was delayed according to the immobilization. And, the higher adsorption capacity of immobilized Chlorella pyrenoidosa was represented in the higher concentration of Pb, the smaller amount of immobilizing agent, and the higher pH of solution. The maximum adsorption capacity of Pb was shown in the adsorption test using Chlorella pyrenoidosa immobilized with Ca-alginate even though it was sensitive pH. The adsorption results properly represented with Freundlich isotherm equations. And, pseudo second-order chemisorption kinetic rate equation was applicable to all the biosorption data over the entire time range. The FT-IR analysis showed that the mechanism involved in biosorption of Pb by Chlorella pyrenoidosa was mainly attributed to Pb binding of carbo-acid and amide group. Adsorbed Pb on immobilized Chlorella prenoidosa was easily desorbed in the higher concentration of desorbents(NTA, HCl, EDTA, $H_2SO_4,\;Na_2CO_3$). Among the several desorbents, NTA showed the maximum desoption capacities of Pb from Chlorella pyrenoidosa immobilized with Ca-alginate and K-carrageenan and EDTA was the most effective in Chlorella pyrenoidosa immobilized with polyacrylamide. The desoprtion efficiency in the optimum condition was 90.0, 83.0, and 80.0%, respectively.

• Microbiology and Biotechnology Letters
• /
• v.26 no.4
• /
• pp.297-302
• /
• 1998

$\beta$-Xylosidase B was produced by Escherichia coli HB101/pKMG12 carrying the xylB gene of Bacillus stearothermophilus No.236 on its recombinant plasmid. The $\beta$-xylosidase B produced was purified by ammonium sulfate fractionation, DEAE-Sepharose CL-6B, Sephacryl S-200 and Superdex 200 HR gel filtration. The purified enzyme showed the highest activity at pH 6.5 and 5$0^{\circ}C$. But, the enzyme was observed to be very sensitive to the pH and temperature of the reaction mixture. The enzyme was activated about 35% of its original activity in the presence of 1 mM of $Mn^{2+}$ but it was completely inhibited by $Ag^{+}$, $Cu^{2+}$and $Hg^{2+}$ions. In contrast with the $\beta$-xylosidase A, the B enzyme was found to have $\alpha$-arabinofuranosidase activity though the activity was fairly low compared with the $\alpha$-arabinofuranosidase produced from the arfI gene of the same Bacillus stearothermophilus. Therefore, $\beta$-xylosidase B is considered to be more suitable than $\beta$-xylosidase A at least for the biodegradation of arabinoxylan. The $K_{m}$ and V$_{max}$ values of the $\beta$-xylosidase B for o-nitrophenyl-$\alpha$-D-xylopyranoside were 6.43 mM and 1.45 $\mu$mole/min, respectively. Molecular mass of the enzyme was determind to be about 54 kDa by SDS-PAGE and 160 kDa by Superdex 200HR gel filtration, indicating that the functional $\beta$-xylosidase B was composed of three identical subunits.s.

• Tuberculosis and Respiratory Diseases
• /
• v.44 no.3
• /
• pp.470-478
• /
• 1997

Background : Phagocytosis is probably the first step for mycobacteria to be virulent in host because virulent strains are more readily phagocytosed by macrophage than attenuated strains. According to the traditional concept, multi-drug resistant strains have been regarded as less virulent. However, this concept has been challenged, since recent studies(reported) showed that the degree of virulence and drug-resistance is not related. The purpose of this study is to evaluate whether the phagocytic activity of M.tuberculosis by peripheral blood mononuclear cells(PBMC) is different according to drug-resistance or host factor. To evaluate this, we estimated the difference of phagocytic activity of drug-resistant and drug-sensitive M.tuberculosis and also estimated the phagocytic activity of PBMC from intractable tuberculosis patients and healthy controls. Methods : PBMC from ten intractable tuberculosis patients and twelve healthy control, and three different strains of heat-killed M.tuberculosis, ie, ADS(all drug sensitive), MDR(multi-drug resistant), and ADR(all drug resistant) were used. After incubation of various strains of M.tuberculosis with PBMC, the phagocytic activity was evaluated by estimating proportion of PBMC which have phagocytosed M.tuberculosis. Results : Drug-resistant strains of M.tuberculosis were phagocytosed easily than drug sensitive strains(Percentage of PBMC phagocytosed M.tuberculosis in healthy control : ADS : $32.3{\pm}2.9%$, ADR : $49.6{\pm}3.4%$, p = 0.0022, Percentage of PBMC phagocytosed M.tuberculosis in intractable tuberculosis patients : ADS : $34.9{\pm}3.6%$, ADR : $50.7{\pm}4.5%$, p = 0.0069). However, there was no difference in phagocytic activity of PBMC from healthy control and intractable tuberculosis patients. Conclusion : Drug-resistant strains of M.tuberculosis were phagocytosed easily than drug sensitive strains and host factors does not seems to influence the phagocytosis of M.tuberculosis.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.13 no.3
• /
• pp.156-158
• /
• 2009

Purpose: Since radiopharmaceuticals are intended for human administration, it is imperative that we should undergo quality control very strictly. Now almost all the PET laboratories have adopted Bacterial Endotoxin Test as the stand quality control method to monitor whether pyrogen is free or not in the product vial containing crude solution. The aim of this study is to find out the reason why false positive result is observed when using commercially available test vial. Materials and Methods: For this experiment, we used commercially available single test kit (Associates of Cape Code. Inc. USA) and we made pH samples by mixing each buffer whose pH ranges are 1.0 to 12.0. Otherwise we made Ethanol samples diluted with distilled water. After making test samples, it added 0.2 mL to the test vial. Assay mixture in the test vial was incubated in a water bath (Chang Shin Co. KOR) for 60 min at $35{\pm}2^{\circ}C$. Results: After incubation period ($60{\pm}1^{\circ}C$), we inverted the test vial about $180^{\circ}$ To know what pH and how many percentage of Ethanol (Fisher Scientific Korea. Ltd) will affect the reaction. With pH buffer, false positive result was observed at pH 1.0 to 5.0 and 7.7 to 12.6 but at pH 5.2 to.7.5, the test results show negative. It's very strange that we couldn't observe negative test result with Tris buffer at pH 8.4, 8.6, 8.8, 9.0. in other case Ethanol, the test result was seen with 5 to 10% Ethanol. But to my surprise we could see very thick gel formation with 100% Ethanol. Conclusions: In this study, we could notice that pH which is too much acidic or alkalic or high concentrated Ethanol would affect Bacterial Endotoxin Test result. As you know, LAL test is sensitive and very reliable method. Therefore, we are needed to elicit the accurate test result as possible as we can.