• Korean Journal of Poultry Science
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• v.28 no.2
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• pp.135-142
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• 2001

A novel sterategy has been established to determine the origin of the Primordial Germ Cells (PGCs) in avian embryos directly and the developmental fate of the PGCs for the application to Poultry biotechnology. Cells were removed from 1) the centre of area pellucida, 2) the outer of area pellucida and 3) the area opaca of the stage X blastoderm (Eyal-Giladi & Kochav, 1976). When the cells were removed from the centre of area pellucida, the mean number of circulating PGCs in blood was significantly decreased in the embryo at stage 15 (Hamburger & Hamilton, 1951) as compared to intact embryos. When the cells were replenished with donor cells, no reduction in the PGCs number was observed. The removal of cells at the outer of area pellucida or at the area opaca had no effect on the number of PGCs. In case, another set of the manipulated embryos were cultured ex vivo to the hatching and reared to the sexual maturity, the absence of germ cells and degeneration of seminiferous tubules was observed in resulting chickens derived from the blastoderm in which the cells were removed from the centre of the area pellucida. It was concluded that the avian Primordial Germ cells are originated at the center of area pellucida. Developmental ability of the cells to differentiate into somatic cells and germ cells in chimeras were analyzed. Somatic chimerism was detected as black feather attributed from donor cells. Molecular identification by use of female - specific DNA was performed. It was confirmed that the donor cells could be differentiated into chimeric body and erythrocytes. Donor cells retained the ability to differentiate into germline in chimeric gonads. More than 70% of the generated chimeras transmitted donor derived gametes to their offspring indicating that the cells at the center of area pellucida had the high ability to differentiate into germ cells. A molecular technique to identify germline chimerism has been developed by use of gene scan analysis. Strain specific DNA fragments were amplified by the method. It would be greatly contributed for the detection of germline chimerism. Mixed- sex chimeras which contained both male and female cells were produced to investigate the developmental fate of male and female cells in ovary and testes. The sex combinations of donor and recipient of the resulting chimeras were following 4 pairs; (1) chimeras (ZZ/ZZ) produced by a male donor (ZZ) and a male recipient (ZZ), (2) chimeras (ZW/ZW) produced by a female donor (ZW) and a female recipient (ZW), (3) chimeras (ZZ/ZW) Produce by a male donor (ZZ) and a female recipient (ZW), (4) chimeras (ZW/ZZ) produced by a female donor (ZW) and a male recipient (ZZ). It was found that genetically male avian germ cells could differentiate into functional ova and that genetically female germ cells can differentiate into functional spermatozoa in the gonad of the mixed- sex chimeras. An ability for introduction of exogenous DNA into the PGCs from stage X blastoderms were analyzed. Two reporter genes, SV-$\beta$gal and RSV-GFP, were introduced into the PGCs. Expression of bacterial/gal was improved by complexing DNA with liposome detectedcc in 75% of embryos at 3 days embryos. At the embryos incubated for 1 day, expression of the GFP was observed all the embryos. At day 3 of incubation, GFP was detected in about 70% of the manipulated embryos. In case of GFP, expression of the transgene was detected in 30 %e of the manipulated embryos. These results suggested that the cells is one of the most promising vectors for transgenesis. The established strategy should be very powerfull for application to poultry biotechnology.

• Journal of Life Science
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• v.34 no.2
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• pp.86-93
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• 2024

Since replication of plasmids must be strictly controlled, plasmids that generally perform rolling circle replication generally maintain a constant copy number by strictly controlling the replication initiator Rep at the transcriptional and translational levels. Plasmid pJB01 contains three orfs (copA, repB, repC or repABC) consisting of a single operon. From analysis of amino acid sequence, pJB01 CopA was homologous to the Cops, as a copy number control protein, of other plasmids. When compared with a CopG of pMV158, CopA seems to form the RHH (ribbon-helix-helix) known as a motif of generalized repressor of plasmids. The result of gel mobility shift assay (EMSA) revealed that the purified fusion CopA protein binds to the operator region of the repABC operon. To examine the functional role of CopA on transcriptional level, 3 point mutants were constructed in coding frame of copA such as CopA R16M, K26R and E50V. The repABC mRNA levels of CopA R16M, K26R and E50V mutants increased 1.84, 1.78 and 2.86 folds more than that of CopA wt, respectively. Furthermore, copy numbers owing to mutations in three copA genes also increased 1.86, 1.68 and 2.89 folds more than that of copA wt, respectively. These results suggest that CopA is the transcriptional repressor, and lowers the copy number of pJB01 by reducing repABC mRNA and then RepB, as a replication initiator.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.228-235
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• 2010

This study was performed to investigate the memory enhancing effect of Poria cocos Wolf (Hoelen cum radix) against scopolamine-induced amnesia in Sprague-Dawley (SD) rats. To induce amnesia, scopolamine (0.75 mg/kg) was intraperitonically injected into SD rats 30 min before starting behavior tests. We have conducted Morris water-maze and Y-maze tests to monitor learning and memory functions. Poria cocos effectively reversed scopolamine-induced memory impairment in SD rats which was represented by an improvement of mean escape latency in water-maze test and spontaneous alterations in Y-maze test. To elucidate possible molecule mechanism, we have measured mRNA as well as protein expression of acetylcholine esterase (AchE), choline acetyltransferase (ChAT), muscarinic acetylcholine receptor (mAchR), and brain-derived neurotrophic factor (BDNF) using RT-PCR and Western blot analysis, respectively. Poria cocos increased mRNA levels of ChAT and mAchR in rat hippocampus compared with those in the scopolamine-injected amnesic group. In addition, protein expression of ChAT and BDNF was also elevated by Poria cocos intake. Furthermore, as an upstrem regulator, the activation of cAMP response element-binding protein (CREB) was assessed by immunohistochemistry. In this immunohistochemical analysis, the phosphorylation of CREB (p-CREB) was reduced by scopolamine injection, which was restored back to control levels by administration of Poria cocos. These results suggest that Poria cocos may improve memory and cognitive deficit in amnesia and have therapeutic potentials through up-regulation of ChAT, mAchR, and BDNF, which seemed to be mediated by activation of CREB.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.317-322
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• 2005

The cycloinulooligosaccharide fructanotransferase (CFTase) gene (cft) from Paenibacillus macerans was subcloned into an E. coli-yeast shuttle vector, pYES2.0, resulting in pYGECFTN. The plasmid pYGECFTN (8.6 kb) was introduced into Saccharomyces cerevisiae SEY2102 cells and then the transformants were selected on the synthetic defined media lacking uracil. The cft gene expression in yeast transformant was demonstrated by the analyses cyclofructan (CF) spots on thin-layer chromatogram. The recombinant CFTase was not secreted into the medium and localized in the periplasmic space. The production of CF was observed after 5 min of the enzymatic reaction with inulin. The optimun pH and temperature for CF production were found to be at pH 8.0 and $45^{\circ}C$, respectively. Enzyme activity was stably maintained up to $55^{\circ}C$. The CF was produced from all inulin sources and was most efficiently produced from dahlia tubers and Jerusalem artichokes.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.105-109
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• 2007

This study was carried out to investigate the biological effects oak wood vinegar. Antimicrobial activity was tested in five microbial species at the concentration of 5 to $50{\mu}l$ of oak wood vinegar by paper disc method. Growth of P. oleovoranse, P. vulgaris, E. coli, S. aureus and Prevotella intermedia was inhibited at a dose of as low as $50{\mu}l$ of oak wood vinegar. Antioxidant activities were measured by using DPPH radical scavenging and SOD-like activity. DPPH radical scavenging and SOD-like activities were 90% and 65% at the concentration of $25{\mu}l\;and\;50{\mu}l$ of oak wood vinegar, respectively. Stimulation of the macrophages RAW264.7 cells with lipopolysaccharide (LPS) resulted in increased production of nitric oxide (NO) in the medium. However, the oak wood vinegar showed marked inhibition of NO synthesis in a dose-dependent manner. This result suggest that oak wood vinegar plays significant role for activation of immune system in the pathogenesis of inflammatory diseases.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.378-384
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• 2012

In aquatic invertebrates, particularly marine gastropods, organotin compounds induce irreversible sexual abnormality in females, which is termed imposex, at very low concentrations. Organotin compounds are agonists for nuclear receptors such as RXRs and $PPAR{\gamma}$. However, the imposex phenomenon has not been reported to act as an antagonist on estrogen receptors in other species, including vertebrates and invertebrates. In order to gain insights into the antagonistic activity of organotin compounds on estrogen receptors (ERs), we examined the inhibitive effect of these compounds on estradiol-dependent ${\beta}$-galactosidase activity using the yeast two-hybrid detection system consisting of a combination of the human estrogen receptor ($hER{\beta}$) ligand-binding domain and the co-activator steroid receptor co-activator-1 (SRC1). Tributyltin-hydroxide (TBT-OH) and triphenyltin-chlorine (TPT-Cl) exhibited an inhibitive effect on $E_2$-dependent transcriptional activity, similar to antagonistic chemicals such as 4-hydroxytamoxifen (OHT) or ICI 182,780, at a very low concentration of $10^{-14}$ M TBT or $10^{-10}$ M TPT, respectively. The yeast growth and transcriptional activity with transcriptional factor GAL4 did not exhibit any effect at the tested concentration of TBT or TPT. Moreover, the yeast two-hybrid system using the interaction between p53 and the T antigen of SV40 large did not describe any effect at the tested concentration of OHT or ICI 182,780. However, the interaction between p53 and T antigen was inhibited at a TBT or TPT concentration of $10^{-9}$ M, respectively. These results indicate that TBT and TPT act as inhibitors of ER-dependent reporter gene transcriptional activation and of the interaction between $hER{\beta}$ LBD and the co-activator SRC1 in the yeast two-hybrid system. Consequently, our data could partly explain the occurrence of organotin compound-induced imposex on the endocrine system of mammals, including humans.

• Korean Journal of Microbiology
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• v.43 no.4
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• pp.256-263
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• 2007

We performed the biochemical characteristics, molecular epidemiologocal analysis, and drug susceptibility test on V. vulnificus isolated from environmental sources in Incheon. For this study, 233 strains were isolated from seawater, sediment, shellfish. V. vulnificus isolates were divided into 15 biochemical groups, which were positive for ONPG and Amygdalin test. Among the 209 strains, 206 (98.6%) strains and 110 (52.6%) strains revealed positive for vvhA and viuB gene, and the viuB gene detection rates of V. vulnificus from seawater, shellfish and sediment were 48%, 48.5% and 61.6%, respectively. From disc diffusion test on 175 isolates, most of strains were sensitive to Imipenem (100.0%), Sulfamethoxazole/trimethoprim (98.9%), Tetracycline, Ciprofloxacin (98.3%), Ampicillin/sulbactam (97.1%), Ohloramphenicol (96.6%), Cefepime (94.9%) and Ceftriaxone (94.8%), multi-drug resistance rates was 31.5% of seawater, 34.4% of sediment and 29.2% of shellfish. PFGE was performed on 233 V. vulnificus isolates with the objective of investigating the extent of genetic diversity of these isolates in our region. We could find that at least 126 different PFGE patterns were generated according by 90% of similarity and 13 clusters by 58% of similarity. The major cluster was type I (44.6%) during the most of the year, and type J was frequent pattern in June and October. There were 9 distinct PFGE types in July, 8 types in August, 7 types in June, 6 types in September, 5 types in October 3 types in May and 1 type in March.

• Tuberculosis and Respiratory Diseases
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• v.52 no.6
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• pp.597-607
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• 2002

Background : Even though it is well known that pulmonary rehabilitation (PR) improves exercise capacity, and the quality of life, in patients with chronic lung diseases, not many patients can attend hospital based intensive PR in Korea. The purpose of this study was to develop a method for a home-based PR program, and study its effectiveness. Materials and Methods : Twenty patients with chronic lung diseases were randomly divided into two groups : a home PR group comprising of 10 male patients, with a mean age of 70 years, and a control group comprising of 10 male patients, with a mean age of 65 years. We developed exercise programs, depending on the exercise capacity of each patient, which were easy to do at home. The PR program consisted of a 12 week period of enforced aerobic (mostly walking) and muscle strengthening exercises, as prescribed by the exercise specialist, in accordance with the functional capacity of the patient. In addition to the education, nutritional and psychiatric consultation was undertaken, and respiratory muscle training arranged. Patients visited hospital every 2 weeks for evaluation and exercise prescription. Results : All patients finished the 12 week course of therapy. Following the home PR, the endurance times and work capacity of the upper and lower extremities were significantly increased in the treatment group in comparison to the controls. The six minute working (Eds note:should) 'working' read "walking"?) distance was increased from $465{\pm}60m$ to $508{\pm}37m$ and the maximal inspiratory pressure from $72.8{\pm}27.2cmH_2O$ to $91.4{\pm}30.9cmH_2O$. The quality of life, as assessed by St Georges Respiratory Questionnaire (SGRQ), was also improved following PR. (Eds note:do you have figures for before and after, and a reference for the SGRQ?i.e. for the main paper.) Conclusion : The home PR program we developed seemed to be applicable, and effective, to most of the patients with chronic lung diseases in this study.

• Journal of Life Science
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• v.33 no.11
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• pp.915-922
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• 2023

Lactic acid bacteria (LAB) are widespread in a variety of environments including fermented dairy products, gastroinstetinal and urogenital tracts of human and animals, plant, soil and water. Leuconostoc mesenteroides DB3 was detected by the strongest antibacterial activities among 24 Leuconostoc strains isolated from Camellia japonica flowers. Acid tolerance of L. mesenteroides DB3 existed up to pH 2.5, but the resistance did not show at pH 2.0, which relatively excellent acid resistance existed. Bile acid tolerance was very stable within the test range to 1.2%. L. mesenteroides DB3 exhibited the optimal growth at 30℃, and showed a slight slow growth when compared with L. mesenteroides KCTC3505, which reached a stationary phase at 18 hr. The pH was changed along with the growth curve, but was maintained above pH 3.98. L. mesenteroides DB3 had higher initial antibacterial activities when compared to L. mesenteroides KCTC3505, but it showed similar activities with the standard strain after the latter part of the logarithmic growth phase. Although lactic acid production in L. mesenteroides DB3 was induced by lower amount in the initial part to the standard strain, it was exhibited by similar amounts after the late logarithmic growth phase. Muicin adhesion of L. mesenteroides DB-3 maintained superior to L. mesenteroides KCTC3505. Both strains showed excellent emulsification ability for kerosene. In summary, we evaluate that L. mesenteroides DB-3 has a high potential for application as probiotics owing to its excellent antibacterial activity, acid resistance, bile acid resistance, and muicin adhesion.

• Journal of Life Science
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• v.33 no.10
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• pp.808-819
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• 2023

This study was conducted to develop a selection marker for the identification of the Bacillus licheniformis K12 strain in microbial communities. The strain not only demonstrates good growth at moderate temperatures but also contains enzymes that catalyze the decomposition of various polymer materials, such as proteases, amylases, cellulases, lipases, and xylanases. To identify molecular markers appropriate for use in a microbial community, a search was conducted to identify variable gene regions that show considerable genetic mutations, such as recombinase, integration, and transposase sites, as well as phase-related genes. As a result, five areas were identified that have potential as selection markers. The candidate markers were two recombinase sites (BLK1 and BLK2), two integration sites (BLK3 and BLK4), and one phase-related site (BLK5). A PCR analysis performed with different Bacillus species (e.g., B. licheniformis, Bacillus velezensis, Bacillus subtilis, and Bacillus cereus) confirmed that PCR products appeared at specific locations in B. licheniformis: BLK1 in recombinase, BLK2 in recombinase family protein, and BLK3 and BLK4 as site-specific integrations. In addition, BLK1 and BLK3 were identified as good candidate markers via a PCR analysis performed on subspecies of standard B. licheniformis strains. Therefore, the findings suggest that BLK1 can be used as a selection marker for B. licheniformis species and subspecies in the microbiome.