• Journal of Digital Contents Society
• /
• v.14 no.2
• /
• pp.255-262
• /
• 2013

Useful applications for English education enable immediate conversion of mobile devices into remote wireless systems for classroom computers. Once the free software has been installed in the main computers in the classroom, using powerpoint, students can operate the computers through their mobile devices by installing Air mouse on them. By using this, the students can draw or write on the "board" to manipulate the educational resources from where they are/from their seats. The study of English language encompasses not only academic study but also language training. Until recently, the issue of the English language learning has been ridden with certain problems-instead of being a tool that facilitates communication, its main purpose has been for school grades, TOEIC, and TOEFL. This study suggests English language learning methodology using various applications such as mobile, VOD English language content, and movie scripts in implementing easy and fun English language learning activities that can be studied regularly. This is operationalized by setting a specific limit on learning and by using various media such as podcast, Apps, to increase interest, motivation, and self-directed learning in a passive learning environment.

• Journal of Korean Biological Nursing Science
• /
• v.3 no.1
• /
• pp.53-61
• /
• 2001

Skin is constantly exposed to air, solar radiation, ozone and other air pollutants formulating free radicals. The reactive oxygen species(ROS), formed under these conditions, are associated with skin cancers, cutaneous photoaging, and cutaneous inflammatory disorders. In this study, we sought to establish an animal model for UVB-induced skin alteration using BALB/c mice. The level of UVB irradiation used in this model was within physiological dose. BALB/c mice were exposed to a single dose of UVB ($200mJ/cm^2$ and were sacrificed at 3, 6, 24, and 48 hours following the irradiation. The effect of a single exposure to UVB irradiation on skin catalase(CAT), superoxide dismutase(SOD), and glutathione peroxidase(GPx) activities were examined. Significant decrease in the activity of all enzymes were observed at 6 hours after irradiation(p<.05). The activity of CAT decreased more sharply than those of SOD and GPx, and then remained depressed until 48 hours after UVB irradiation, whereas the activity of GPx recovered to basal level at 48 h after UVB irradiation. Our results indicate that BALB/c mouse could be an adequate animal model of UVB irradiation experiment. These results will also provide fundamental knowledge for the effective nursing strategies in reducing UV-induced skin disorders.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.1 no.1
• /
• pp.1-6
• /
• 2007

Applying the gyroscopic technology, HeadZmouse has been developed to simulate left and right mouse click, double click, drag and drop, and even a wheel function for navigating web. This device was designed to work on both PC and Macintosh environments using a USB cable. The first time you use this device, you'll find out how much freedom it offers to someone who can't use his or her hands freely. Rather than being tied to your computer, simple manipulation such as blowing an air (breathing) into a sonic sensor can simulate all the functions which standard mouse has, even including a wheel function. Also, a macro-interface device has been developed. By storing repetitive tasks into a memory, you can carry out repetitive tasks just by clicking a button once.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.21 no.1
• /
• pp.49-54
• /
• 2011

In order to develop the methods for exposure assessment and find susceptibility markers for the workers who are exposed to low doses of toluene, xylene and other chemical in petroleum industries, we investigated the application of P-450 expression in human lymphocytes utilizing mouse monoclonal anti-rat CYP2B1/2, the levels of toluene and xylene in air and their metabolite levels in urine with the levels of expressed CYP2B1/2 proteins. The general characteristics such as age, smoking and drinking habit were no significant difference between the control and exposed workers, but the working durations and working hours were significantly different. Workers in exposed group were exposed to the mean of 2.1 ppm (range, 0.00-4.54) of toluene and 0.3 ppm (rang, 0.00-1.23) of xylene. The mean concentration of urinary hippuric acid was low and less than 1/5 of the biological exposure index recommended by the Ministry of Employment and Labor Korea. Methyl hippuric acid in urine was not detected in control and exposed workers. Also, there were no significant differences in the levels of the urinary metabolites between the control and exposed group. When chemiluminescence dot blottings were carried out utilizing mouse monoclonal antibody against CYP2B1/2, the strong density dots corresponding to a mouse monoclonal antibody was observed in the human lymphocytes from the exposed workers. These results suggested that the chemiluminescence dot blot assay for CYP of lymphocytes should be valuable for identifying CYP expression as biomarkers in the workers exposed to toluene and xylene.

• Clinical and Experimental Reproductive Medicine
• /
• v.18 no.2
• /
• pp.153-162
• /
• 1991

The present study was undertaken to clarify the role of calcium ion as a factor for the maturation of follicle-enclosed mouse oocytes. Follicles were isolated with two sharp needles under a stereomicroscope from mouse(ICR) ovaries which were treated PMSG 5 IU 45 hours previously. Isolated follicles were cultured for 14-16 hours in an organ culture system at $37^{\circ}C$, 5% $CO_2$ in air and in a 100% humidified incubator by treatment of hCG, EDTA and $^{45}Ca^{++}$. Culture medium was Modified Hank's Balanced Salt Sol. (MHBS) and addition of hCG (human chorionic gonadotropin) was made into two doses level 0.4 IU and 0.8IU from the stock sol. and also $^{45}Ca^{++}$ was treated in the culture medium. To explain the role of calcium, calcium chelating agent EDTA was treated to the culture of the mouse follicle-enclosed oocytes. Two observations were made in the present study; nucleus phase and $^{45}Ca^{++}$ uptake into the oocyte. HCG induced oocyte maturation in the follicle about two folds as much as the control group, whereas there is no difference in oocyte maturation between 0.4 IU and 0.8 IU of hCG. Optimum level of hCG seems to be 0.4 IU/ml in the mouse follicle culture. HCG stimulated $^{45}Ca^{++}$ uptake into the oocyte of the follicles by two folds. $^{45}Ca^{++}$ uptake in the control group is about 2.5 folds in comparison of the EDTA(1.71mM) treated group. However, calcium uptake in the EDTA treated groups tends to increase depending on the decrease of EDTA concentration. These observations suggest that firstly, hCG stimulates maturation of the oocyte of the follicle, secondly, $Ca^{++}$ influx is induced by hCG and thirdly, $Ca^{++}$ influx by the treatment of EDTA decreases as a dosage-dependent process. This $Ca^{++}$ uptake may take place by the changes of permeability which was induced by hCG treatment. That is, $Ca^{++}$ influx may trigger the resumption of oocyte maturation. It is further necessary in the future study how this $Ca^{++}$ uptake is induced by hCG and increases permeability of the follicle and oocyte.

• Clinical and Experimental Reproductive Medicine
• /
• v.31 no.3
• /
• pp.155-168
• /
• 2004

Objective: Melatonin, which is secreted by pineal gland play an important role in the regulation of ovarian function via seasonal rhythm and sleep in most mammals. It also has a role in the protection of cells by removing toxic oxygen free radicals brought about by metabolism. In the present study, effects of melatonin on the mouse oocyte maturation were examined using two different culture conditions provided with 5% or 21% oxygen concentration. Material and Method: Immature mouse oocytes were obtained from the ovarian follicles of $3{\sim}4$ weeks old ICR strain mice intraperitoneally injected with 5 I.U. PMSG 44 hour before. Under stereomicroscope, morphologically healthy oocytes with distinct germinal vesicle (GV) were liberated from the graafian follicles and collected using mouth-controlled micropipette. They were then cultured for 17 hour at $37^{circ}C$, 5% $CO_2$ and 21% $O_2$ (95% air) or 5% $CO_2$, 5% $O_2$ and 90% $N_2$. New modified Hank's balanced salt solution (New MHBS) was used as a culture medium throughout the experiments. Effects of melatonin were examined at a concentration of $0.0001{\mu}M$, $0.01{\mu}M$ or $1.0{\mu}M$. For the prevention of spontaneous maturation of immature oocytes during culture, dibutyryl cyclic AMP (dbcAMP) and/or hypoxanthine were included in the medium. Results: Under 21% oxygen condition, oocytes cultured in the presence of $0.01{\mu}M$ melatonin showed a significantly higher maturation rates, in terms of germinal vesicle breakdown (95.0% vs 89.0%) and polar body formation (88.1% vs 75.4%), compared to those cultured with $0.0001{\mu}M$ or $1.0{\mu}M$ melatonin. However, no difference was observed in oocytes cultured under 5% oxygen whether they were treated with melatonin or not. In the presence of $0.01{\mu}M$ melatonin, oocytes either cultured under 21% or 5% oxygen exhibited no difference in the polar body formation (85.6% vs 86.7%). However, in the absence of melatonin, oocytes cultured under 21% oxygen exhibited lower polar body formation (74.7%). When oocytes were cultured in the presence of dbcAMP alone or with varying concentrations of melatonin, those treated with both compounds always showed better maturation, i.e., germinal vesicle breakdown and polar body formation, compared to those cultured with dbcAMP alone. At the same concentration of melatonin, however, oocytes exposed to 21% oxygen showed poor maturation than those to 5% oxygen. Similar results were obtained from the experiments using hypoxanthine instead of dbcAMP. Conclusion: Based upon these results, it is suggested that melatonin could enhance the meiotic maturation of mouse oocytes under 21% oxygen concentration, and release oocytes from the meiotic arrest by dbcAMP or hypoxanthine regardless of the concentration of oxygen, probably via the removal of oxygen free radicals.

• Radiation Oncology Journal
• /
• v.13 no.3
• /
• pp.205-214
• /
• 1995

Purpose : To investigate the effect of Ginkgo biloba extract (GBE) on hypoxic cell fraction and metabolic status in fibrosarcoma (FSa II) of C3H mouse. Materials and Methods : Fibrosarcoma (FSa II) 6 mm in diameter, growing in the right hindleg muscle of C3H mouse was used for estimation of hypoxic cell fraction using comparison of $TCD_{50}$. Radiation was given one hour after administration of GBE (100 mg/kg. i.p.) with or without priming dose of GBE (100 mg/kg, i.p.) given 24 hours earlier. Radiation was also given under air breathing condition or clamp hypoxia without GBE as controls. $^{31}p$ NMR spectroscopy was performed before and one hour after administration of GBE with or without priming dose of GBE. Results : $TCD_{50/120's}$ were 81.7 (77.7-86.0) Gy when irradiated under clamped hypoxia 69.6 (66.8-72.5) Gy under air breathing condition. 67.5 (64.1-71.1) Gy with a single dose of GBE (100 mg/kg) given one hour before irradiation, and 62.2 (59.1-65.5) Gy with two doses of GBE given at 25 hours and one hour before irradiation. The hypoxic cell fractions, estimated from $TCD_{50/120's}$, were $10.6{\%}$ under air breathing condition, $7.2{\%}$ after a single dose of GBE, and $2.7{\%}$ after two doses of GBE. The results of $^{31}P$ NMR spectroscopy were as follow. PCr/Pi ratio was $0.27{\pm}0.04$ and $0.40{\pm}0.04$ before and one hour after a single dose of GBE (p<0.05), respectively, without priming dose and $0.30{\pm}0.02$ and $0.71{\pm}0.04$, respectively, with priming dose (p<0.01). These findings indicate that the metabolic status is slightly improved after a single dose and markedly after repeated administrations. Conclusion : GBE decreases the hypoxic cell fraction and imprvoes the meta bolic status of tumor, probably by increasing the blood flow and delivery of oxygen and nutrients, resulting in increased radiosensitivity of tumor.

• Applied Microscopy
• /
• v.23 no.1
• /
• pp.35-55
• /
• 1993

cis-Dichlorodiammineplatinum (II) (cis-Platin), a metallic compound, has widely been used as an effective anticancer chemotherapeutic agent. The precise mechanism of action of this agent is still unknown, but it is postulated that cis-Platin may act on the cancer cell like bifunctional alkylating agents. Although this agent is very beneficial to the patients with cervical cancer, germinoma of testis, neuroblastoma and others, it may also damage to the normal cell so that many side effects; severe hemorrhagic enterocolitis, bone marrow depression, renal damage and liver damage will develope. This experiment has been undertaken to pursue the cytotoxic effects of the cis-Platin on the ultrastructures of the interalveolar septum in the mouse lung. A total of 55 healthy male mice of ICR strain were used as experimental animals and divided into 5 mice of normal control group and 50 mice of cis-Platin treated group. The mice of cis-Platin treated group were sacrificed by carotid exsanguination at 6, 12, 24 hours, 3 days and 7 days after intraperitoneal injection of 6.0 mg of cis-Platin ($Abiplatin^R$ Abic Co. Ltd.) per kg of mouse body weight. The specimen obtained from the lower lobe of left lung were sliced into $1mm^3$ and prefixed with 2% glutaraldehyde -2.5% paraformaldehyde solution prepared with Millonig's phosphatae buffer solution (pH 7.4) at $4^{\circ}C$ for 3-4 hours. After postfixation with 1% osmium tetroxide solution all specimens were embedded in Epon 812. Ultrathin sections about $600-800{\AA}$ in thickness were stained with uranyl acetate and lead citrate and observed with Hitachi-600 electron microscope. The results obtained were as follows: 1. Local swellings with increase of electron density and number of pinocytic vesicles in the cytoplasms of the type I pneumocyte and endothelial cell of the blood air barrier in interalveolar septum of cis-platin treated mice were observed. 2. Cisternae of rough endoplasmic reticulum were dilated and sacculated in association with detachment of membrane bound ribosomes of the type II pneumocyte in interalveolar septum of cis-Platin treated mice. 3. Swollon mitochondria with uneven electron density of their matrix were observed in the type II pneumocyte of interalveolar septum in the cis-Platin treated mice. 4. The lamellae of lammelar bodies in type II pneumocyte of interalveolar septum in cis-Platin treated mice were devoided or transformed into homogeneous electron dense material. It is consequently suggested that cis-Platin would induce the cellular edema of type I pneumocyte and endothelial cell, and degenerative changes of cytoplasmic organelles of the type II pneumocyte in the interalveolar septum of the mouse lung.

• Korean Journal of Animal Reproduction
• /
• v.17 no.2
• /
• pp.113-120
• /
• 1993

To provide the optimal culture conditions for the developm,ent of in vit개 produced embryos, we have been investigated various culture media as well as co-cultrue systems using porcine cumulus cells or mouse fetal fibroblast cells. Porcine ovaries were brought to the laboratory from local slaughter house within 1 hour after slaughtering and cumulus oocytes complexes were recovered from antral follicles(3~5mm) with 23 gauge needle. To maturate follicular oocytes, cumulus oocytes complexes were washed three times with TCM-199 containing 25mM HEPES and incubated(39$^{\circ}C$, 5% CO2 in air) in various maturation media for 42 hrs. Ejaculated and liquid storaged boar spermatozoa capacitated with different sperm capacitation methods and media were rpepared for fertilizing of matured follicular oocytes in vitro. Fertilization was performed by adding 5~10${\mu}\ell$ fo capacitated spermatozoa containing 1~5$\times$105 sperm/ml to droplets. Eighteen to twenty-eight hours after sperm insemination, fertilized eggs were washed three times with culture media and transferred to the various culture media, to the culture media with a monolayer of somatic cells. The in vitro development rates of 1-cell embryos cultured with three times with culture media and transferred to the various culture media, to the culture media with a monolayer of somatic cells. The in vitro development rates of 1-cell embryos cultured with three different media, m-KRB, BECM and TCM-HEPES were 0~1.0%, showing extremely lower rates. Especially, most of embryos were observed to arrest the development beyond 4-cell stages. The rates of embryos developed to 2-, 4-, 8-, 16-, 32-cell and morula or blastocyst stage in co-culture with porcine cumulus cells and mouse fetal fibroblast cells were 61.1~67.0%, 59.0~58.0%, 42.5~43.1%, 28.4~30.2% and 20.4~21.0%, respectively. These development rates upto morula or blastocyst stages were significantly higher than those of the embryos cultured in the basic culture medium(P<0.01). These findings suggest that co-culture of in vitro fertilized eggs with porcine cumulus cells or mouse fetal fibroblast cells enhance the development of fertilized eggs to morula or blastocyst stage in vitro.

• Clinical and Experimental Reproductive Medicine
• /
• v.24 no.3
• /
• pp.377-383
• /
• 1997

The effects of embryo number and incubation volume on the development of mouse embryos were evaluated. The growth rate of two-cell mouse embryos to attached blastocyst stage and the growth rate of blastocysts to early somite stage were assessed after culture in different incubation volumes and embryo densities. Embryos were collected from ICR female mice superovulated with pregnant mare serum gonadotropin and human chorionic gonadotropin and mated by ICR males. In experiment 1, groups of one, five, ten, twenty 2-cell embryos were cultured in 10-, 50-, 500-, 1000-${\mu}l$ drops of BWW media under mineral oil at $37^{\circ}C$ in a humidified atmosphere of 5% $CO_{2}$ and 95% air. As the incubation volume decreased, significantly (p<0.05) higher rates of embryos reached morular and blastocyst stage on day 3 and 4 culture, respectively. In experiment 2, groups of one, five, ten, twenty blastocysts were cultured in 1- and 2-ml volumes of CMRL 1066 media under same condition as in experiment 1. However the reverse was the result. Decreasing the number of embryos incubated per volume from 1 to 20 significantly (p<0.05) increased the number of blastocysts reaching the late egg cylinder (LEC) and early somite (ES) stage on day 6 and 8 culture, respectively, regardless of incubation volume. Blastocysts cultured in 2ml had higher (p<0.05) development rates to LEC and ES stage on day 6 and 8 culture, respectively, than embryos cultured in 1ml. Our results suggest that the effects of embryo number and incubation volume on the development of mouse embryos are stage specific and the shifting point was between hatching and EEC stage.