• Journal of Microbiology and Biotechnology
• /
• v.13 no.6
• /
• pp.841-845
• /
• 2003

In order for engineered tissues to find clinical utility, the engineered tissues must function appropriately. However, smooth muscle (SM) tissues engineered in vitro with a conventional tissue engineering technique may not exhibit contractile functions, because smooth muscle cells (SMCs) cultured in vitro typically revert from a contractile, differentiated phenotype to a synthetic, nondifferentiated phenotype and lose their ability to contract. SMCs in vivo typically reside in mechanically dynamic environments. We hypothesized that cyclic mechanical stretch induces the features of SMCs in in vitro engineered tissues to be similar to those of SMCs in native tissues. To test the hypothesis, aortic SMCs were seeded onto elastic, three-dimensional scaffolds and cultured in vitro under a cyclic mechanical stretching condition for 4 weeks. A significant cell alignment in a direction parallel to the cyclic stretching direction was found in the SM tissues exposed to cyclic stretching. The cellular alignment and alignment direction were consistent with those of native vascular SM tissues, in which SMCs in vivo align in the radial direction (parallel to stretching direction). In control tissues (SM tissues engineered without stretching), cells randomly aligned. The expression of SM ${\alpha}-actin$ and SM myosin heavy chain, phenotypic markers of SMCs in a contractile state, was upregulated in the stretched tissues by 2.5- and 2.0-fold, respectively, compared to SMCs in the control tissues. The cellular features of alignment and contractile phenotype of SMCs in the SM tissues engineered under a mechanically dynamic environment could allow the engineered SM tissues to exhibit contractile functions.

• Journal of Applied Biological Chemistry
• /
• v.61 no.2
• /
• pp.151-155
• /
• 2018

In this study, cinnamon essential oil (CEO) was formulated as emulsifiable concentrate (EC) and a granule. For the evaluation of their negative effects on the ecosystem, acute toxicities against Cyprinus carpio was determined in a static condition. The formulations were made using CEOs extracted by 3 different methods (steam distillation (SD), solvent extraction and supercritical fluid extraction (SFE)) and were tested to obtain $LC_{50}$ values. Among the ECs, EC including CEO extracted by SFE showed highest acute toxicity against C. carpio. Among the granules, a granule including CEO extracted by SD showed highest acute toxicity against C. carpio. Nevertheless, $LC_{50}$ of EC and a granule formulation with CEOs was higher than toxicity level III of pesticide standardized by Korea rural development administration. These results were similar to those using zebrafishes. Chronic toxicities were not found for 45 days in zebrafishes until $500{\mu}gL^{-1}$ level of EC formulation including CEO obtained by the SD. Based on these results, EC formulation of CEOs may be considered to be used as environmental-friendly natural insecticides in accordance with the standards.

• The Journal of the Korean Society for Microbiology
• /
• v.21 no.3
• /
• pp.363-373
• /
• 1986

We developed a giant colony test system with rapidly growing mycobacteria by stab-culture with a loopful inoculum of cells into Middlebrook 7H10 agar medium containing soluble extracts of the fruits of Gardenia jasminoides(7H10-crocin agar medium) and assessed the significance of the giant colony test with 28 strains of 10 clusters of rapidly growing mycobacteria classified by the simple biological 5-test characters. Of the 10 clusters of mycobacteria tested, some of strains which belonged to cluster No. 1a, 5a and 11a did grow as gravis types, whereas most of other clusters gave mitis or intermedius types in their colonial sizes at 12 days culture. By this test, pathogenic strains of M. fortuitum-chelonei complex which belonged to cluster No. 5a, b, 7a and 8a, b could be divided into gravis, intermedius and mitis colony types and the gravis ones were characterized by bluish-white "mushroom-shaped" colonies with central complexes in the texture, whereas the intermedius gave grayish-white "flower-shaped" colonies with radiated folds, but without any central complexes. The mitis colonies were characterized by grayish-white smooth or smooth mucoid colonies and were common among the clusters in their shapes. The colony of M. chelonei was bluish-white mitis type and was characterized by its hilly rhizoid colony. The gravis colony of cluster No. 1a identified as M. phlei was characterized by yellow "round straw- mat-shaped" or "chrysanthemum-shaped" colony with whole complexes in the texture, and the gravis colonies of the cluster No. 11a gave grayish-white "flower-shaped" colonies with central stamens, radiating trough and fine cup-shaped strands in the texture. The four colony types of pathogenic species of M. fortuitum-chelonei complex on 7H10-crocin agar medium were distinctive from those of other clusters of rapidly growing mycobacteria and these results indicated that the giant colony test, in conjunction with the simple 5-test characters, would be of value in the differentiation of M. fortuitum complex from other clusters of rapidly growing mycobacteria.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.22 no.6
• /
• pp.723-730
• /
• 2016

Domestic Manila clam production has been reduced due to coastline changes and environmental degradation, but aquaculture industry is facing difficulties caused by an increase in imports. It is important to recognize the integral habitat environment in order to do sustainable aquaculture. The habitat environment of Manila clams (Ruditapes philippinarum) is closely related to the productivity of aquaculture farms. This study investigated 3 indexes, survival (sediment type, hydrodynamic), growth (Chlorophyll a, DIN, DIP) and environment (water temperature, dissolved oxygen, sediment chemical oxygen demand, ignition loss) as indicators of habitat characteristics for a tidal flat farm in Geunso Bay (Pado and Beopsan) from June 2015 to May 2016. As a result, Pado (maximums.; sand 48.76 %, hydrodynamic 10.59 cm/s, Chlorophyll a 12.70 ug/L, exposure time 3 hours, DO 18.65 mg/L) had a higher sand content, faster current speed, more abundant nutrients and DO, providing more favorable conditions for Manila clams than Beopsan (maximums.; sand 37.40 %, hydrodynamic 6.02 cm/s, Chlorophyll a 6.41 ug/L, exposure time 7 hour, DO 14.81 mg/L). In fact, Pado showed a higher density than Beopsan. This study considered the habitat environments of Pado and Beopsan to provide a basis for optimal management practices and potential suitable sites in Geunso bay.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.6
• /
• pp.434-441
• /
• 2009

The effect of varying sulfate concentration on continuous fermentative hydrogen production was studied using enriched mixed microflora in continuously fed reactor. Glucose was used as a model substrate for carbohydrates, and hydraulic retention time (HRT) was maintained at 1, 0.5, 0.25 day, respectively. Sulfate concentration was 0${\sim}$20,000 mg/L and the operating pH was maintained at 5.5. The experimental results indicate that hydrogen production is not affected by high sulfate concentration and shorter HRT of 0.25 day enhance hydrogen production. At HRT 1, 0.5, 0.25 day, the hydrogen production rate and hydrogen yield were 2.6, 4.6, 9.4 L/day, and 2.0, 1.8, 1.6 mol $H_2$/mol glucose, respectively. Residual sulfate content was 96${\sim}$98, 95${\sim}$97, and 94${\sim}$97% at HRT 1, 0.5, 0.25 day which show that no sulfate reduction occurred in the reactor during the experiments. Results of Fluorescence In Situ Hybridization (FISH) may indicate the presence of HPB (hydrogen producing bacteria) under all experimental conditions. However, SRB (sulfate reducing bacteria) were not found.

• Reproductive and Developmental Biology
• /
• v.33 no.1
• /
• pp.35-40
• /
• 2009

The objectives of this study was to evaluate the efficiency of the bacteria eliminated sperm by percoll gradient method on sperm quality and embryo cleavage in vitro in pig. The semen of miniature pig collected by gloved-hand method pre-warmed ($37^{\circ}C$) in thermos bottle, and separated by 65% percoll. Analysis of sperm ability was estimated by examining viability, capacitation and acrosome reaction using chlortetracycline (CTC) and the abnormality. Also, fertility of sperm was monitored with cleavage rate of embryo after IVF using separated and un-separated sperm by percoll. The result, viability of separated sperm was significantly(p<0.05) higher($83.6{\pm}$2.0 vs $59.0{\pm}4.4%$) than un-separated sperm. The results of CTC analysis showed the percentage of F- and B-patterned separated sperm was higher in separated that than un-separated sperm. On the contrary, the percentage of AR-patterned form unseparaed sperm was significantly(p<0.05) higher($13.6{\pm}0.8$ vs $8.1{\pm}0.6%$) than separated sperm. Also, abnormality of un-separated sperm was significantly(p<0.05) higher($2.2{\pm}0.4$ vs $16.8{\pm}2.8%$) than separated sperm. However, the cleavage rates of embryo using separated sperm by percoll and un-separated sperm had not significantly difference on 2 cell stage(9.25 vs 11.88%), 4 cell stage(26.76 vs 24.51%) and >4 cell stage(63.99 vs 63.61%) at 48h of IVF. Therefore, the sperm separated by percoll method showed improvement in sperm quality than un-separated sperm in miniature pig.

• Analytical Science and Technology
• /
• v.31 no.5
• /
• pp.185-194
• /
• 2018

At the end of November 2010, livestock infected with foot and mouth disease (FMD) were buried, increasing concern about secondary pollution of drinking water and groundwater with odor. Hence, measures to reduce pollution of drinking water and groundwater are needed. In this study, based on livestock type and soil texture, five pilot-scale burial sites were monitored for the past three years from Feb 2012 to 2015. Leachate from the site was analyzed for 90 compounds. A detailed investigation has been completed, looking into organic matter decomposition characteristics of the buried bodies, relevant trace elements thereof, and in particular metabolite concentration changes such as the degree of decomposition of a carcass. From the results, no detectable heavy metals, including cadmium and arsenic, were measured. Among animal types, the rate of cattle decomposition is faster than swine decomposition, and the decomposition of the bodies were performed in sequence from sand, clay loam, sandy loam.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.53 no.2
• /
• pp.237-243
• /
• 2020

Listeria sp. is one of the pathogenic bacteria causes the infection listeriosis, through mainly raw food such as fishery food, dairy food and vegetables. Listeria sp. is a Gram-positive, non-spore-forming, motile, and facultative anaerobic bacterium. Because of the tolerance of Listeria sp. to low temperature and high salt concentration, it is very difficult to prevent them contaminated in the food, which do not require heating, especially, such as raw fishery products. So prevention and removal of bacterial contamination at the food manufacturing stage is the best method. In this study, therefore, several natural products including Psidium guajava and Geranium thunbergii were screened to investigate the antibacterial activity against Listeria sp., with expectation of fewer side effects and fewer resistance problems. Significant effects of two extracts were confirmed by well diffusion assay, MIC assay, and growth inhibition assay. P. guajava and G. thunbergii showed MIC values at 64-256 ㎍/mL meaning strong antibacterial activities against 6 kind of Listeria sp. tested. And the growth of Listeria sp. in the liquid media was actually inhibited by the addition of these two extracts.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.5
• /
• pp.711-717
• /
• 2007

In this study, two cell types from porcine females, namely fetal fibroblasts (pFFs) and adult ear fibroblasts (pAEFs) and two passages (3-4 and 7-8) were investigated by evaluating the development rate, blastocyst cell number and the incidence of apoptosis. No significant differences were observed in the cleavage rates of cloned and IVF embryos. The blastocyst rates between the embryos cloned with pFFs ($15.1{\pm}3.2$) and pAEFs ($10.4{\pm}2.6$) did not differ significantly but was significantly (p<0.05) lower in pAEFs than that in IVF ($22.5{\pm}4.5$) embryos. Total cell number in pFFs ($28.4{\pm}4.3$) and pAEFs cloned blastocysts ($24.2{\pm}5.1$) was significantly (p<0.05) lesser than IVF control ($35.4{\pm}3.2$). Apoptosis rates between cloned blastocysts differed significantly (p<0.05) and were significantly (p<0.05) higher than IVF embryos. The blastocyst rates between the cloned embryos cloned with different cell passages did not differ significantly but in embryos cloned with 7-8 cell passage was significantly (p<0.05) lower than the IVF control. Apoptosis signals were detected in IVF and cloned embryos as early as day 3 and the rates of apoptosis increased concurrently with the embryo development. In conclusion, high apoptosis during in vitro preimplantation development resulted in low development rate and total cell number of cloned embryos. Moreover, based on the apoptotic incidence in cloned blastocysts, fetal fibroblasts are more suitable for production of cloned embryos in porcine.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.15 no.3
• /
• pp.177-185
• /
• 2012

Wave field measurements were made over a period of 18 days to study the spatial distribution of incident wave on seaweed tarm field around Gumil-up Sea, Wando, Korea. These measured data were compared with data from the Geomun-do ocean weather/wave observation buoy. A numerical simulation model that combined the offshore design wave with the seasonal normal incoming wave was used to study the incident wave distribution surrounding a seaweed farm. The results are summarized as follows. (1) On-site wave measurements showed that the major relationship between maximum and significant wave height was $H_{max}=1.6H_{1/3}$. (2) Offshore incident wave energy reaching the coast was greatly influenced by the wind direction. A north wind reduced the incident wave energy and a south wind increased it. (3) The calculated maximum wave height under the design wave boundany conditions was in the range of 4~5 m and the reduction in the incident wave height ratio ranged from approximately 38.1% to 47.6% at Gumil-up Sea. Under normal wave conditions, the maximum wave heights were 3.6~4.0 m in summer and 2.3~2.7 m in winter while the reduction in the incident wave height ratio was about 41.8% to 49.1%. (4) The sea state in the southern area of Gumil-up was the most affected by ocean waves, whereas the sea state in the northern area was very stable. The significant wave ratio in the south was about six times that in the north.