• Journal of Embryo Transfer
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• v.19 no.3
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• pp.245-255
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• 2004

In recent years, an increasing number of studies on pig in vitro maturation(IVM) and in vitro fertilization(IVF) have been separated. the wide range of new technologies, including that in applied molecular genetics, has increased this interest. the production of viable porcine embryos in vitro is a prerequisites for the successful production of transgenic pigs to date. The efficiency of IVM/IVF techniques in the porcine is lower than that obtained in other species such as cattle and mouse. The several problems are generally thought to be the cause of poor results: the low rate of MPN formation derived from inadequate IVM of oocytes, the high incidence of polyspermy after IVF and cell blocking at 4 cell during embryos culture. For there reasons overcoming, many studies have been conducted to improve in vitro embryo-genic competence of oocytes. In the last several years, many maturation culture media have been evaluated and various exogenous factors such as hormones and grows factors have been tested to improve the efficiency of porcine in vitro system. In the study several antioxidants have been examined to improve in vitro fertilization and development of porcine oocytes. In this study, several antioxidants were examined to determine the effects on the development of oocytes to the cleavage, morula and blastocyst stage when added at the maturation(IVM) or in vitro fertilization(IVF) or in vitro culture(IVC) of porcine embryos. Porcine oocytes were matured, fertilized and embryos were cultured in defind conditioned medium in vitro with or without supplementation with the antioxidents of cysteine, catalase and glutathione. 1. Significant improvement of blastocyst rate (27.2％ versus 15.4％, p<0.05) were achieved when catalase(500U/$m\ell$) were added to TCM-199 medium and morula rate(72.0％ versus 53.9％, p<0.05) were significantly higher when glutathione(1.0mM/$m\ell$) were added to TCM-199 medium than those of control. 2. In mTBM medium for oocytes fertilization, the addition of cysteine, catalase and glutathione had no positive effect on embryonic development. glutathione had no positive effect on embryonic development. In conclusion, this study shows that addition of catalase, gluththione during IVM improved the rate of porcine embryo development.

• International Journal of Highway Engineering
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• v.6 no.3 s.21
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• pp.1-7
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• 2004

Roads, like bikeways, parkways and walks, are to be just capable of supporting light traffic and traveling public, but they are required to be human friendly and environmental-oriented. Lately soil-solidifier mixture, a kind of soil-cement, has developed and has been applied to the recycling and environment-oriented pavement as the surfacing material. Soil-solidifier pavement structure has been designed by only experience. To design this pavement mechanically, it is necessary to find out basic engineering properties of soil-solidifier mixture. This study focuses on finding out mechanical characteristics of the mixture according to mixture proportions and aging. Test molds with various mixture proportions are made, and then unconfined strength tests are performed for test molds with aging of the mixture. As the result of this study, it is found that the strength of the mixture increases with amount of cement and that maximum strength is achieved at 6%$\sim$8% of the ratio of solidifier and water. The strength increase rapidly until 14 days, after then slowly. After 28 days the strength of the mixture approaches to the constant value. The heat of hydration during curing of the mixture is measured no significantly. It also shows that temperature characteristics of the mixture is similar to that of soil. Since this mixture is mixed with soil and is able to improve engineering problems in pavement due to temperature, this mixture is expected to use effectively in the environment-oriented pavement for light traffic.

• Parasites, Hosts and Diseases
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• v.24 no.2
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• pp.115-120
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• 1986

This study was carried out to reveal the effect of temperature, salinity and aeration on maturation and hatching of Fibricola seoulensis eggs. The eggs were incubated and were observed daily for the appearance of eyespots and hatching. The results were summarized as follows. 1. From $4{\sim}5$ days after incubation in distilled water at $28^{\circ}C$ or at $11{\sim}26^{\circ}C$, the eyespots began to appear and the rates of eggs with eyespots were over 90% in $28^{\circ}C$ on the 7th or 8th day. However, eyespots did not appear in $5{\sim}15^{\circ}C$ or $4^{\circ}C$ by the 18th day. 2. The mature eggs began to hatch at the 8th day, and hatching rate 2 weeks after incubation was over 90% at $28^{\circ}C$, but it was below 5% at $11{\sim}26^{\circ}C$, and 0% at $5{\sim}15^{\circ}C$ and at $4^{\circ}C$. 3. Aeration did not influence the appearance of eyes pots nor hatching. 4. In salines under 0.6%, the rates of eyespots appearance were over 90% on the 7th day. The rate was 55.0% in 0.9% at 20 days, and 0% in 1.2%. 5. The hatching rates in salines below 0.3% concentration were over 90% by 14 days of incubation. However, the rate decreased to 44% in 0.6% saline and to 0% over 0.9% salinity. 6. The eggs incubated in the dark hatched in 12.5% on the 10th day, but hatching rate of mature eggs increased to 85.7% within 2 hours after exposure to light. Above results demonstrated that the best temperature for maturation and hatching of F. seoulensis eggs was $28^{\circ}C$, and the miracidia began to hatch at $8{\sim}9$ days after incubation. In the field, hatching and invasion into snails of the miracidia may occur from May to September in Korea. In salines under 0.3% concentration maturation and hatching were not influenced, but as salinity increased hatching was inhibited more than maturation was.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.235-244
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• 2004

In this study, we compared the levels of methylotrophic bacterial community diversity in the leaf samples of 19 rice cultivars collected from three regions of Korea. Nineteen pink pigmented isolates showing characteristic growth on methanol were obtained. Physiological and biochemical characters of each isolate were examined according to methods described in Bergey's Manual of Systematic Bacteriology. When phylotypes were defined by performing numerical analysis of 37 characteristics, four distinct clusters were formed. The two reference strains, Methylobacterium extorquens AM1 and Methylobacterium fujisawaense KACC10744 were found to group under cluster IV and cluster III respectively. Cluster I diverged on the basis of nitrate reduction and four isolates showed tolerance upto 0.5 M NaCl concentrations. Two strains in cluster I and III were found to possess methane utilizing properties. Most of the isolates in all the four clusters utilized monosaccharides, disaccharide and polyols as carbon source. When the isolates were subjected for indole-3-acetic acid (IAA) analysis in the presence of L-tryptophan, only 8 isolates exhibited IAA production. In addition, the nitrogen source in the medium was found to influence the IAA production. Addition of $(NH_4)_2SO_4$ in the medium led to a 2 to 30 fold increase in the indole synthesis. However, $KNO_3$, $NH_4NO_3$ and $NH_4Cl$ substitution did not significantly stimulate the synthesis of IAA in the growth medium. Result of gnotobiotic root elongation assay significantly increased roots and shoots lengths, and number of lateral roots, which is mediated by IAA production in the culture medium. The rice seedlings primary roots from seeds treated with methylotrophic isolates were on average 27 to 56% longer than the roots from seeds treated with the uninoculated seeds. In addition, application of different high concentrations of authentic IAA ($400g\;mL^{-1}$) to roots of rice seedlings inhibited root growth. However, the IAA concentration from 10 to $200g\;mL^{-1}$, IAA promoted root growth of rice seedlings. These results suggest that bacterial IAA plays a major role in the development of the host plant root system.

• Tuberculosis and Respiratory Diseases
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• v.64 no.4
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• pp.285-292
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• 2008

Background: A diagnosis of malignant pleural effusion is clinically important, as the prognosis of lung cancer patients with malignant pleural effusion is poor. The diagnosis will be difficult if a cytological test is negative. This study was performed to investigate whether the detection of hypermethylation of the p16 (CDKN2A) and retinoic acid receptor b2 (RARB2) genes in pleural fluid is useful for a diagnosis of malignant pleural effusion. Methods: Pleural effusion was collected from 43 patients and was investigated for the aberrant promoter methylation of the RARB2 and CDKN2A genes by use of methylation-specific PCR. Results were compared with findings from a pleural biopsy and from pleural fluid cytology. Results: Of 43 cases, 17 cases of pleural effusion were due to benign diseases, and 26 cases were from lung cancer patients with malignant pleural effusion. Hypermethylation of the RARB2 and CDKN2A genes was not detected in the case of benign diseases, independent of whether or not the patients had ever smoked. In 26 cases of malignant pleural effusion, hypermethylation of RARB2, CDKN2A or either of these genes was detected in 14, 5 and 15 cases, respectively. The sensitivities of a pleural biopsy, pleural fluid cytology, hypermethylation of RARB2, hypermethylation of CDKN2A, or hypermethylation of either of the genes were 73.1%, 53.8%, 53.8%, 19.2%, and 57.7%, respectively; negative predictive values were 70.8%, 58.6%, 58.6%, 44.7%, and 60.7%, respectively. If both genes are considered together, the sensitivity and negative predictive value was lower than that for a pleural biopsy, but higher than that for pleural fluid cytology. The sensitivity of hypermethylation of the RARB2 gene for malignant pleural effusion was lower in small cell lung cancers than in non-small cell lung cancers. Conclusion: These results demonstrate that detection of hypermethylation of the RARB2 and CDKN2A genes showed a high specificity, and sensitivity was higher than for pleural fluid cytology. With a better understanding of the pathogenesis of lung cancer according to histological types at the molecular level, and if appropriate genes are selected for hypermethylation testing, more precise results may be obtained.

• Journal of Periodontal and Implant Science
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• v.37 no.sup2
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• pp.447-463
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• 2007

Periodontal ligament (PDL) cells have been known as multipotential cells, and as playing an important rolesin periodontal regeneration. The PDL cells are composed of heterogeneous cell populations which have the capacity to differentiate into either cementoblasts or osteoblasts, depending on needs and conditions. Therefore, PDL cells have the capacity to produce mineralized nodules in vitro in mineralization medium which include ascorbic acid, ${\beta}$-glycerophosphate and dexamethasone. In spite of these well-known osteoblast like properties of PDL cells, very little is known about the molecules involved in the formation of the mineralized nodules in the PDL cells. In the present study, we analysed gene-expression profiles during the mineralization process of cultured PDL cells by means of a cDNA microarray consisting of 3063 genes. Nodules of mineralized matrix were strongly stained with alizarin red S on the PDL cells cultured in the media with mineralization supplements. Among 3,063 genes analyzed, 35 were up-regulated more than two-fold at one or more time points in cells that developed matrix mineralization nodules, and 38 were down-regulated to less than half their normal level of expression. In accord with the morphological change we observed, several genes related to calcium-related or mineral metabolism were induced in PDL cells during osteogenesis, such as IGF-II and IGFBP-2. Proteogycan 1, fibulin-5, keratin 5, ,${\beta}$-actin, ${\alpha}$-smooth muscle actin and capping protein, and cytoskeleton and extracellular matrix proteins were up-regulated during mineralization. Several genes encoding proteins related to apoptosis weredifferentially expressed in PDL cells cultured in the medium containing mineralization supplements. Dkk-I and Nip3, which are apoptosis-inducing agents, were up-regulated, and Btf and TAXlBP1, which have an anti-apoptosis activity, were down-regulated during mineralization. Also periostin and S100 calciumbinding protein A4 were down-regulated during mineralization.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 1999.06a
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• pp.97-117
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• 1999

This study was performed to investigate the effect of pork on the cadmium detoxification in rats. Ninety male Sprague-Dawley rats weighing $125.3{\pm}1.4g$ were divided into five groups based on cadmium treatment(0, 25, 50, 100, 250ppm) and five levels of Cd in AIN-76 purified diet had been fed for 8 weeks. Cadmium was supplemented with a form of $CdCl_2$.. During following 8 weeks of intoxication, casein was replaced by pork and the effect of pork on cadmium- detoxification was compared with casein. After 8 weeks of Cd intake had resulted in apparent cadmium intoxication; reduced growth rate, enlarged kidney and testis, decreased hematocrit value and hemoglobin content in response to the supplemented Cd levels in the diets. Discontinuing cadmium feeding, the body weights were relieved. Pork-fed groups seemed to have higher body weight than casein-fed groups. Hemoglobin content and hematocrit value became normal range at detoxification stage. The weights of liver, kidney, and testis were decreased along with cadmium intake. However, organ weight ratio was not affected by cadmium. Cadmium accumulation in liver and kidney showed a tendency to increase in the cadmium-exposed groups. The levels of metallothionein were also significantly elevated in the tissues of liver in response to the levels of Cd supplemented(p<0.05). Cadmium concentration in kidney was two times higher than that in liver. Cadmium removal rate of liver was higher than that of kidney. Cadmium accumulation of the pork-fed group was lower than that of casein. Especially, the factors which affected the cadmium contents in kidney were $Cd^{***}$ and $Cd{\times}pork^{***}$. Metallothionein(MT) was increased with cadmium, and MT was not likely to be affected by pork. Based on the findings from gross lesion, rats fed 250ppm of Cd were externally emaciated, had exposed penis and observed atrophies of kidney and testis. Histopathological observation seemed that the liver of groups feeding Cd supplemented diets showed cellular degeneration and accumulation of eosinophilic materials in the capillaries. In kidney, rats fed Cd diets had shown tubular epithelium degeneration and lesions of basophilic materials, while testis were weakened in numbers of spermatid and sporadically enlarged of giant cells. But the rats administered cadmium-detoxified diet supplemented pork for 7 weeks were shown individually decreased lesions compared with the rats supplied with casein diet.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.80-86
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• 2007

This experiment was conducted to investigate the changes of pork meat quality characteristics exposed to ozone gas for 5, 10, and 15 min and then vacuum packaged during storage for 0, 5, 10, 15, and 20 day at $4^{\circ}C$. The ozone gas exposed groups of pork loin cuts (OZM) had slightly higher pH value compared to the control at day 0 and 5 (p<0.01). The 15 min exposure of ozone gas groups showed significantly (p<0.01) higher TBARS value than that of control at the day 15 and 20. However, there was no significant difference in all groups at day 0,5, and 10. The CIE $L^*$ and $b^*$ values of OZM showed no significant difference between control and ozone gas treated groups during storage. The loin cut color of ozone gas exposure for 15 min had significantly lower CIE $a^*$ values than the other groups at day 0,5, and 15 (p<0.01). The aerobic plate count and coliform bacteria count of pork loin cuts exposed ozone gas significantly (p<0.01) was reduced at day 0 by about $0.45-1.04\;log_{10}CFU/g$ and $0.26-0.30\;log_{10}CFU/g$, respectively. As ozone gas exposure time extended, the aerobic plate count and coliform bacteria count of OZM were increased at day 0, 5, and 10 (p<0.01). However, there were no significant differences observed among groups at day 20 in the counts of aerobic and coliform bacteria. In conclusion, the meat cuts exposed to ozone gas for 5 and 10 min before packing may be a reasonable packing method regarding the effects of ozone level on meat oxidation, color change and microbial reduction.

• Radiation Oncology Journal
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• v.13 no.4
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• pp.321-330
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• 1995

Purpose : To evaluate whether the early pulmonary irradiation can prevent or decrease the pulmonary damage and contribute to improve ultimate survival in paraquat lung. Materials and Methods : From Jun. 1987 to Aug. 1993, thirty patients with paraquat poisoning were evaluated. Fourteen of these patients were received pulmonary irradiation(RT). All of the patients were managed with aggressive supportive treatment such as gastric lavage, forced diuresis, antioxidant agents and antifibrosis agents. Ingested amounts of paraquat were estimated into three groups(A : minimal 50cc). Pulmonary irradiation was started within 24 hours after admission(from day 1 to day 11 after ingestion of paraquat). Both whole lungs were irradiated with AP/PA parallel opposing fields using Co-60 teletherapy machine. A total of 10Gy(2Gy/fr. x 5days) was delivered without correction of lung density. Results : In group A, all patients were alive regardless of pulmonary irradiation and in group C, all of the patients were died due to multi-organ failure, especially pulmonary fibrosis regardless of pulmonary irradiation. However, in group B, six of 7 patients($86{\%}$) with no RT were died due to respiratory failure, but 4 of 8 patients with RT were alive and 4 of 5 patients who were received pulmonary irradiation within 4 days after ingestion of paraquat were all alive though radiological pulmonary change. One patient who refused RT after 2Gy died due to pulmonary fibrosis. All 3 patients who were received pulmonary irradiation after 4 days after ingestion were died due to pulmonary fibrosis in spite of recovery from renal and hepatic toxicity Conclusion : It is difficult to find out the effect of pulmonary irradiation on the course of the paraquat lung because the precise plasma and urine paraquat concentration were not available between control and irradiation groups. But early pulmonary irradiation within 4 days after paraquat poisoning with aggresive supportive treatment appears to decrease Pulmonary toxicity and contribute survival in patients with mouthful ingestion of paraquat who are destined to have reversible renal and hepatic damage but irreversible pulmonary toxicity.

• Korean Journal of Microbiology
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• v.40 no.4
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• pp.286-294
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• 2004

Between 1997 and 1998 in Korea, 56 isolates of Escherichia coli were obtained from pig suffering diarrhea. Among those, 38 isolates that showed the hemolytic activity, antimicrobial resistance, and toxin production were studied. Among 38 isolates, thirty-six isolates $(94.7\%)$ were resistant to tetracycline, 27 isolates $(71.0\%)$ were resistant to ampicillin, 26 isolates $(68.4\%)$ were resistant to chloramphenicol, and 21 isolates $(55.2\%)$ were resistant to trimethoprim, while none was resistant to aztreonam, amikacin, and norfloxacin. Among these iso­lates, 21 isolates $(55.3\%)$ were multiple drug resistant to at least four different class antimicrobial agents. Extended spectrum $\beta-lactamase$ producing isolates were not detected in the double disk synergy test. In these hemolytic Escherichia coli, heat-stable enterotoxin $(89.5\%)$ was the most prevalent toxin, followed by vero­toxins $(47.4\%),$ and then heat-labile enterotoxin $(31.6\%).$ Except 8 isolates $(21.0\%)$ which produced ST only, 12 isolates $(31.6\%)$ produced ST and LT, 13 isolates $(34.2\%)$ produced ST, VT, and VTe, and 5 isolates $(13.2\%)$ produced VT and VTe. However, none produced all 4 types of toxin, simultaneously. The predominant serotype could not be determined by the agglutination method. Sixteen isolates $(42.1\%)$ were strongly adhered to T-24 bladder cell and 17 isolates $(44.7\%)$ were to Caco-2 intestinal cell. Especially, 11 strains $(28.9\%)$ were evaluated as strongly adhesive to both T-24 cells and Caco-2 cells. Genes for toxin and the antimicrobial resistance were transferred to clinical isolates of Escherichia coli from human urine by the filter mating method. Results suggest the possibility that antimicrobial resistance and toxin can be transferred from animals to humans by direct con­tact of resistant bacteria as well as gene transfer, although there was no correlation between toxin production, adherent activity, and antimicrobial resistance among hemolytic E. coli isolated from pig suffering diarrhea.