• Development and Reproduction
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• v.12 no.1
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• pp.19-30
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• 2008

Proper development of fertilized oocyte to blastocyst is a key step in mammalian development to implantation. During development of preimplantation embryos, the mammalian embryo needs supply the energy substrate for keep viability. Usually mammalian oocyte get substrate especially energy substrate from oviduct and uterus, because it does not store much substrate into cytoplasm during oogenesis. Carbohydrates are known as a main energy substrate for preimplantation stage embryos. Glucose, lactate and pyruvate are essential component in preimplantation embryo culture media and there are stage specific preferences to them. Glucose transporter and $H^+$-monocarboxylate cotransporter are a main mediator for carbohydrate transport and those expression levels are primarily under the control of intrinsic or extrinsic factors like insulin and glucose. Other organic substances, amino acids, lipids and nucleotides are used as energy substance and cellular regulation factor. Though since 1960s, successful development of fertilized embryo to blastocyst has been accomplished with chemically defined medium for example BWW and give rise to normal offspring in mammals, the role of metabolites and the regulation of intermediary metabolism are still poorly understood. Glucose may permit expression of metabolic enzymes and transporters in compacting morula, capable of generating the energy required for blastocyst formation. In addition, it has been suggested that the cytokines can modulate the metabolic rate of carbohydrate in embryos and regulate the preimplantation embryonic development through control the metabolic rate. Recently we showed that lactate can be used as a mediator for preimplantation embryonic development. Those observations indicate that metabolites of carbohydrate are required by the early embryo, not only as an energy source, but also as a key substrate for other regulatory and biosynthetic pathways. In addition metabolites of carbohydrate may involve in cellular activity during development of preimplantation embryos. It is suggested that through these regulation and with other regulation mechanisms, embryo and uterus can prepare the embryo implantation and further development, properly.

• Environmental Analysis Health and Toxicology
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• v.15 no.4
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• pp.131-137
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• 2000

The release of hazardous waste materials into the environment poses serious risks in humans and ecosystems. The risk assessment of environmental pollutants including hazardous chemicals requires a comprehensive measurement of hazard and exposure of the chemicals that can be achieved by toxicity evaluation using a biological system such as biomarkers. In this report we have tried to develop a biomarker used to elucidate a molecular basis of, and to monitor abnormal behaviors caused by diazinon in Japanese medaka (Oryzias latipes) as a model organism. First, an attempt was made to clone tyrosine hydroxylase gene from Japanese medaka that would be a candidate for a biomarker for neuronal modulations and behaviors. For monitoring experiments at behavioral and molecular biological levels, the fish were treated under different sublethal conditions of diazinon and their behavioral responses were observed . In this study we have successfully cloned a partial TH gene from the medaka fish through PCR screening of an ovary cDNA library. DNA sequencing analysis revealed that the amplified fragment was 327 bp encoding 109 amino acids. Comparing the DNA sequence of medaka TH with other species, TH gene revealed the DNA sequence was completely identical to that of rat TH. In the RT-PCR, 330 Up of mRNA was consistently amplified in all the treated samples including control There were no significant differences in the TH expression level regardless of treating concentrations (1∼5,000 ppb) and time (0∼48 hr) The reason appeared to be that RT-PCR was not performed using through a quantitative analysis normalized against an actin gene expression. Organ or tissue - specific detection of TH activity and mRNA as biomarkers will be a useful monitoring tool for neurobehavioral changes in fish influenced by toxic chemicals. Furthermore, quantitative analysis of locomotive patterns and its correlation with the neurochemical and molecular data would be highly useful in measuring toxicity and hazard ofvarious environmental pollutants.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.4
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• pp.358-383
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• 2015

The concept of 'carbon footprint' has been developed as a means of quantifying the specific emissions of the greenhouse gases (GHGs) that cause global warming. Although there are still neither clear definitions of the term nor rules for units or the scope of its estimation, it is broadly accepted that the carbon footprint is the total amount of GHGs, expressed as $CO_2$ equivalents, emitted into the atmosphere directly or indirectly at all processes of the production by an individual or organization. According to the ISO/TS 14067, the carbon footprint of a product is calculated by multiplying the units of activity of processes that emit GHGs by emission factor of the processes, and by summing them up. Based on this, 'carbon labelling' system has been implemented in various ways over the world to provide consumers the opportunities of comparison and choice, and to encourage voluntary activities of producers to reduce GHG emissions. In the agricultural sector, as a judgment basis to help purchaser with ethical consumption, 'low-carbon agricultural and livestock products certification' system is expected to have more utilization value. In this process, the 'cradle to gate' approach (which excludes stages for usage and disposal) is mainly used to set the boundaries of the life cycle assessment for agricultural products. The estimation of carbon footprint for the entire agricultural and forestry sector should take both removals and emissions into account in the "National Greenhouse Gas Inventory Report". The carbon accumulation in the biomass of perennial trees in cropland should be considered also to reduce the total GHG emissions. In order to accomplish this, tower-based flux measurements can be used, which provide a direct quantification of $CO_2$ exchange during the entire life cycle. Carbon footprint information can be combined with other indicators to develop more holistic assessment indicators for sustainable agricultural and forestry ecosystems.

• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.319-326
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• 1999

Recently, it is continuously rising to concern about the health risk being induced by microorganisms in food such as Escherichia coli O157:H7 and Listeria monocytogenes. Various organizations and regulatory agencies including U.S.FPA, U.S.DA and FAO/WHO are preparing the methodology building to apply microbial quantitative risk assessment to risk-based food safety program. Microbial risks are primarily the result of single exposure and its health impacts are immediate and serious. Therefore, the methodology of risk assessment differs from that of chemical risk assessment. Microbial quantitative risk assessment consists of tow steps; hazard identification, exposure assessment, dose-response assessment and risk characterization. Hazard identification is accomplished by observing and defining the types of adverse health effects in humans associated with exposure to foodborne agents. Epidemiological evidence which links the various disease with the particular exposure route is an important component of this identification. Exposure assessment includes the quantification of microbial exposure regarding the dynamics of microbial growth in food processing, transport, packaging and specific time-temperature conditions at various points from animal production to consumption. Dose-response assessment is the process characterizing dose-response correlation between microbial exposure and disease incidence. Unlike chemical carcinogens, the dose-response assessment for microbial pathogens has not focused on animal models for extrapolation to humans. Risk characterization links the exposure assessment and dose-response assessment and involve uncertainty analysis. The methodology of microbial dose-response assessment is classified as nonthreshold and thresh-old approach. The nonthreshold model have assumption that one organism is capable of producing an infection if it arrives at an appropriate site and organism have independence. Recently, the Exponential, Beta-poission, Gompertz, and Gamma-weibull models are using as nonthreshold model. The Log-normal and Log-logistic models are using as threshold model. The threshold has the assumption that a toxicant is produce by interaction of organisms. In this study, it was reviewed detailed process including risk value using model parameter and microbial exposure dose. Also this study suggested model application methodology in field of exposure assessment using assumed food microbial data(NaCl, water activity, temperature, pH, etc.) and the commercially used Food MicroModel. We recognized that human volunteer data to the healthy man are preferred rather than epidemiological data fur obtaining exact dose-response data. But, the foreign agencies are studying the characterization of correlation between human and animal. For the comparison of differences to the population sensitivity: it must be executed domestic study such as the establishment of dose-response data to the Korean volunteer by each microbial and microbial exposure assessment in food.

• Journal of Food Hygiene and Safety
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• v.23 no.3
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• pp.264-270
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• 2008

Phytic acid(PA) (Inositol hexaphosphate, $IP_6$) is a naturally occurring polyphosphorylated carbohydrate that is present in substantial amounts in almost all plants and mammalian cells. Recently PA has received much attention for its role in anticancer activity. In the present study, the preventive effects of PA on colon carcinogenesis were investigated. Six-week old Fisher 344 male rats were fed a AIN-93G purified diet and PA(0.5% or 2% PA in water) for 8 weeks. The animals received two ($1^{st}\;and\;2^{nd}$ week) injections of azoxymethane(AOM, 15 mg/kg b.w.) to induce colonic aberrant crypt foci(ACF). After sacrifice, the total numbers of aberrant crypts(AC) and ACF in colonic mucosa were examined after staining with methylene blue. Blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. AOM induced the total numbers of $142.3{\pm}22.3$ ACF/colon and $336.6{\pm}55.1$ AC/colon. PA at the doses of 0.5 and 2% decreased the numbers of ACF and AC/colon in a dose-dependent manner. The numbers of ACF/colon and AC/colon by PA at the dose of 0.5% were $124.4{\pm}28.5\;and\;302.7{\pm}67.3$, respectively. PA at the dose of 2% significantly decreased the ACF and AC numbers to $109{\pm}18.1\;and\;254.8{\pm}50.6$, respectively(p<0.01). Especially, 2% PA significantly reduced the number of large ACF(${\geq}4$ AC/ACF) from $26.8{\pm}6.2$ ACF/colon to $15{\pm}6.7$ ACF/colon(p<0.01). Although some parameters in blood counts and serum chemistry were changed compared with the control, no specific toxicity was found. These findings suggest that phytic acid can be a chemopreventive agent for colon carcinogenesis resulting from inhibition of the development of ACF in the F344 rat.

• The Journal of the Korean Society for Microbiology
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• v.21 no.3
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• pp.311-329
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• 1986

The experimental exposure of animals to sources of ultraviolet radiation (UVR) which emit their energy primarily in the UVB region (280-320nm) is known to result in a number of well-described changes in the recipient's immune competence. Two such changes include a depressed capacity to effectively respond immunologically to transplants of syngeneic UVR tumors and a markedly reduced responsiveness to known inducers of delayedtype (DTH) and contact hypersensitivity (CH) reactions. The results of experiments that were designed to elucidate the mechanisms responsible for UVR-induced immunomodulation have implicated: 1) an altered pattern of lymphocyte recirculation, 2) suppressor T cells(Ts), 3) deviations in systemic antigen presenting cell (APC) potential. 4) changes in the production of interleukin-1-like molecules, and 5) the functional inactivation of epidermal Langerhans cells in this process. The exposure of skin to UVR, therefore, causes a number of both local and systemic alterations to the normal host immune system. In spite of this seeming complexity and diversity of responses, our recent studies have established that each of the UVR-mediated changes is probably of equal importance to creating the UVR-induced immunocompromised state. Normal animals were exposed to low dose UVR radiation on their dorsal surfaces under conditions where a $3.0\;cm^2$ area of skin was physically protected from the light energy. Contact sensitization of these animals with DNFB, to either the irradiated or protected back skin, resulted in markedly reduced CH responses. This was observed in spite of a normal responsiveness following the skin sensitization to ventral surfaces of the UVR-exposed animals. Systemic treatment of the low dose UVR recipients with the drug indomethacin (1-3 micrograms/day) during the UVR exposures resulted in a complete reversal of the depressions observed following DNFB sensitization to "protected" dorsal skin while the altered responsiveness found in the group exposed to the skin reactive chemical through directly UVR-exposed sites was maintained. These studies implicate the importance of EC as effective APC in the skin and also suggest that some of the systemic influences caused by UVR exposure involve the production of prostaglandins. This concept was further supported by finding that indomethacin treatment was also capable of totally reversing the systemic depressions in CH responsiveness caused by high dose UVR exposure (30K joules/$m^2$) of mice. Attempts to analyze the cellular mechanisms responsible established that the spleens of all animals which demonstrated altered CH responses, regardless of whether sensitization was through a normal or an irradiated skin site, contained suppressor cells. Interestingly, we also found normal levels of T effector cells in the peripheral lymph nodes of the UVR-exposed mice that were contact sensitized through normal skin. No effector cells were found when skin sensitization took place through irradiated skin sites. In spite of such an apparent paradox, insight into the probable mechanisms responsible for these observations was provided by establishing that UVR exposure of skin results in a striking and dose-dependent blockade of the efferent lymphatic vessels in all peripheral lymph nodes. Therefore, the afferent phases of immune responses can apparently take place normally in UVR exposed animals when antigen is applied to normal skin. The final effector responses, however, appear to be inhibited in the UVR-exposed animals by an apparent block of effector cell mobility. This contrasts with findings in the normal animals. Following contact sensitization, normal animals were also found to simultaneously contain both antigen specific suppressor T cells and lymph node effector cells. However, these normal animals were fully capable of mobilizing their effector cells into the systemic circulation, thereby allowing a localization of these cells to peripheral sites of antigen challenge. Our results suggest that UVR is probably not a significant inducer of suppressor T-cell activity to topically applied antigens. Rather, UVR exposure appears to modify the normal relationship which exists between effector and regulatory immune responses in vivo. It does so by either causing a direct reduction in the skin's APC function, a situation which results in an absence of effector cell generation to antigens applied to UVR-exposed skin sites, inhibiting the capacity of effector cells to gain access to skin sites of antigen challenge or by sequestering the lymphocytes with effector cell potential into the draining peripheral lymph nodes. Each of these situations result in a similar effect on the UVR-exposed host, that being a reduced capacity to elicit a CH response. We hypothesize that altered DTH responses, altered alloresponses, and altered graft-versus-host responses, all of which have been observed in UVR exposed animals, may result from similar mechanisms.

• The Journal of the Korean Society for Microbiology
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• v.22 no.1
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• pp.79-93
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• 1987

The result of various researches mainly in search of 194 Shigella strains, isolated by the Health Research Centers(situated in Seoul city, Inchon city, Pusan city, Kyonggi-Do, Kangwon-Do, Chungchongnam and Buk-Do, Kyongsangnam and Buk-Do, Jollanam and Buk-Do, and Jaeju-Do) in addition to those clinical laboratories of all the general hospitals situated down twon Seoul, conducted during the month of Jan. through Dec. 85, through the reisolating-activity program following its transportation into the laboratory, particularly for a complete check on its correctiveness, are as follows: 1. Isolation processes were performed with the 194 strains obtained from each placeduring the period of investigation: 164 Strains(84.5%) of Sh. flexneri, B group; 6 Strains(3.1%) of Sh. boydii, C group; 24 Strains(12.3%) of Sh. sonnei, D group, which means there's quite a lot in B group while Sh. dysenteriae, A group was not isolated at all. 2. The isolation rate of the 164, B group for subserotype was 1b, 84(51.2%) the highest one, 2(1.2%) on 3a the lowest one, 4, on C group; In D group subserotype II showed 14(58.4%) more than subserotype I. 3. The biological data on sexuality regarding the isolation-strain showed traditional particularity. But the subserotype 1b in B group 2(2.4%) showed gas-growth from glucose. In subserotype 1a, the indole-growth was 88.9% on masculine which was considerably a good one. In the test of arginine dihydrolase subserotype I among D group showed 100% masculine rate. The subserotype 6 among B group showed 92.5% masculine. In the dissolution test of manitol, all subserotypes showed 100% maculine except subserotype 1b. In the dissolutioning test of rhamnose, the subserotype I among D group showed 100% masculine which is the unusual one. 4. Interms of the area among 13 districts examined, Kangwon-Do had 41(21.1%) which is the highest one on its ratio. 5. In terms of season on the strain isolation category, 44(22.7%) is the number isolated in April which is the highest one. 6. In terms of ages, the strain isolation ratio was notably high above the ages of 60 which was 34(17.5%). Next one was 29(14.9%) which was under the ages of 4. 7. In terms of sex, female was 113 or 58.2% while male was 74 or 38.2%, which means the female had more than the male. 8. The result of the resisting capability on the usage of 12 antibiotic medication was; 100% on chloramphenicol; 94.3% on tetracycline, 82.0% on streptomycin, 76.3% on carbenicillin, 74.7% on ampicillin, in regular order. The strain source bearing multimedication resisivity against the 5 antibiotic medication is as many as 117 or 60.3%. Of which 43.3% of 1b sub serotype, B group was the best one, and thus the resistivity against the antistrain medication seems the tendency is being changed. The summing up of the above result shows the total specific strains isolated in each branch in Korea is 194, of which the main type is Sh. flexneri 84.5%. The isolating rate is almost evenly spreading, although the Kangwon-Do showed the highest rate on the above data. It also shows female is higher than male on its statistics. The tendency on age category showed both on old and infancy generations high. However, the resistant capability against antibacteria medication or vaccine was still remaining on habitual one, particularly tending towards multimedication or vaccine trend.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.183-187
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• 2004

Radioactivity in foodstuffs was surveyed for reference in amending regulation on the maximum permitted levels of radioactive contamination of foodstuffs. Most domestic and imported (?) foodstuffs were sampled, some domestic items collected around nuclear power plants to compare site-specific contamination. The collected samples were dried and ashed. Radioactivity in foodstuffs was measured using HPGe gamma spectrometer, Cs-137 activity ranged from 0.025-0.053, 0.045-0.500, 0.062-0.105, 0.025-1.151, 0.021-0.145 and 0.046-0.155 Bq/kg-fresh in cereals, pulses, mot vegetables (potato), ginsengs, meat, and marine products, respectively, with imported dried ginseng showing the highest radioactivity, Results reveal radioactivity in foodstuffs collected in 2002 is far below the maximum permitted levels of 370 Bq/kg. No significant differences were observed in radioactivity among sampling sites and between domestic and imported foodstuffs.

• Horticultural Science & Technology
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• v.17 no.5
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• pp.572-577
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• 1999

Research was initiated to evaluate plant growth regulator effects on the vertical shoot growth of Korean lawngrass and to determine desirable growth regulator and its rate. The experiments were conducted twice at different sites in 1995. All the tested growth regulators inhibited the growth, but the inhibition period was variable among the product in Experiments I and II. During the first week after treatment, there was approximately 10 to 20% growth reduction in most of the treated plots. In the amidochlor-treated plots, growth suppression was effective for 3 to 4 weeks at low to medium rates ($0.60mL{\cdot}m^{-2}$). A Type II growth regulator, trinexapac-ethyl exceeding the medium rate of $0.08mL{\cdot}m^{-2}$ consistently tended to suppress vertical shoot growth for 8 weeks, being above 35% reduction in both experiments. In the plots applied with mefluidide, growth suppression appeared with foliar discoloration 3 or 4 days earlier than the other growth regulators and continued to work till the 8 weeks after treatment. Suppression intensity on vertical shoot growth increased with time after treatment up to a certain period of time, depending on growth regulators. Generally, the higher the application rate, the greater the suppression intensity. Seasonal variation of activity and effectiveness of growth regulators was observed, resulting in lower suppression intensity in July than in June. It is expected to reduce mowing requirements by 30 to up to 60% for a certain period with a specific growth regulator. In low to medium maintenance of Korean lawngrass turf, a long-term suppression may be more effectively accomplished with trinexapac-ethyl rather than mefluidide and amidochlor in terms of vertical shoot growth inhibition. Therefore, turf managers will need to select proper growth regulator and determine optimum rate of application for turfgrass management, based on a defined period of mowing reduction.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.1
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• pp.77-82
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• 2008

Objective: This study was performed to investigate the efficacy and safety of radiofrequency (RF) myolysis under transvaginal ultrasound guidance. Methods: Transvaginal RF myolysis had been performed in one hundred nine women with uterine leiomyoma at Chung-Ang University hospital between Dec. 2004 and Mar. 2007. All patients, mean aged $42.8{\pm}5.8$ years, desired their uterine conservation. Patients underwent physical examination, transvaginal pelvic ultrasound for measurement of the lesions preoperatively. Follow up was done at 1 week, 1 month, 3 months, 6 months after RF myolysis by same physician and measurement of size and volume of myoma and improvement of myoma specific symptoms such as menorrhagia and dysmenorrhea were checked at each visit. Results: The mean maximal diameter of myomas treated by RF myolysis was $6.1{\pm}0.5\;cm$ and average time of the procedure was $16.3{\pm}8.5$ minutes. A significant decrease of myoma size and volume was observed at 1 month after myolysis. Mean reduction in maximal diameter was $29.9{\pm}4.8%$ at 1 week (p<0.001), $41.5{\pm}1.5%$ at 1 month (p=0.05), $46.2{\pm}3.9%$ at 3 months (p=0.003), $54.6{\pm}6.1%$ at 6 months (p<0.001) after RF myolysis respectively. Mean reduction in volume was $44.4{\pm}8.3%$ (p=0.001), $68.1{\pm}4.2%$ (p=0.035), 73.9$73.9{\pm}4.8%$ (p=0.042), $84.5{\pm}5.1%$ (p<0.001) at the same follow up period respectively. Significant improvement of symptom was observed at 3 months after RF myolysis. Transient low abdominal pain and prolonged vaginal bleeding were detected in 3 patients each but spontaneously resolved and no serious complication has been noticed or found. Conclusion: This study shows transvaginal RF myolysis could be a safe and effective method to treat uterine leiomyoma, allowing uterine conservation with significant volume reduction and rapid return to normal activity.