• Korean journal of applied entomology
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• v.55 no.3
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• pp.235-243
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• 2016

The winter cherry bug, Acanthocoris sordidus (Thunberg), is an insect pest hat damages plants from Solanaceae and Convolvulaceae. The developmental period from egg to adult averages 76 days at $25^{\circ}C$. Adult egg-laying occurred irregularly via spawning, averaging 195 (up to 468) eggs per individual on the abaxial leaf surface of the host plant. Results of linear regression indicated that the lower developmental threshold temperature was $13.9^{\circ}C$ and the effective accumulated temperature was 526.3 DD. Data from a pepper field in 2015 indicated that overwintering adults first appeared during late June (daily average temperature = $25.7^{\circ}C$), reaching maximum density by early September. A choice test examining colonization preferences using a net cage and a Y-tube olfactometer revealed that females gravitated toward conspecifics (other females, males, or both), whereas males moved toward empty areas. Finally, we found that communal breeding results in a longer developmental period and higher eclosion rates than solitary breeding. Developmental periods and eclosion rates were also for colonies in a large space than for those in a small space. This outcome suggests that colonization effects on insect development are stronger in a smaller area.

• Journal of Environmental Health Sciences
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• v.44 no.5
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• pp.468-479
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• 2018

Objectives: Recently, a report was published that the humidifier disinfectant CMIT/MIT did not cause developmental toxicity and was not detected in systemic circulation as a result of an inhalation toxicity test. Therefore, this study was carried out to investigate any associations between CMIT/MIT exposure and developmental toxicity using the in vivo apical toxicity test method. Methods: Groups of pregnant ICR mice were instilled in the trachea with chloromethylisothiazolinone/methylisothiazolinone (CMIT/MIT) using a visual instillobot over a period of seven days from days 11 to 17 days post-coitum. For the in vivo apical toxicity test method, an $LD_{50}$-based dose-range finding model was applied to decide the dose range for inducing developmental toxicity. Results: Among the groups of 0, 0.1, 0.5, 1.0, and 1.5 mg ai/kg/day CMIT/MIT, the exposure groups of 0.5 mg and 1.0 ai/kg/day CMIT/MIT were estimated to reflect the thresholds for the stillbirth and death of pregnant mice, respectively. The groups of 0.5, 1.0, and 1.5 mg ai/kg/day CMIT/MIT induced stillbirth rates of 2.57, 10, and 53.8%, respectively. Another exposure group of 0.75 mg ai/kg/day CMIT/MIT did not induce any deaths of pregnant mice and resulted in a stillbirth rate of 8% in only one of six pregnant mice. Conclusions: CMIT/MIT can induce stillbirth in pregnant mice. It was also concluded that CMIT/MIT moves through the pulmonary circulation system and then continues on through systemic circulation and the placenta. There is a possibility of stillbirth and other health causalities in humans beyond the lungs caused by CMIT/MIT exposure.

• Journal of Korean society of Dental Hygiene
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• v.9 no.3
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• pp.357-368
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• 2009

The purpose of this study was to examine the state of dental treatment among disabled patients by the type of disability. After the medical records of 531 disabled patients who received treatment at the pediatric dentistry in K university hospital, the following findings were given: 1. As for age distribution by year, the rate of patients aged 10 or down rose to 42.5 from 5.1 percent, and the 16-20 age group increased from 16.7 to 24.8 percent. But the rates of patients aged between 11 and 15 and aged 21 and up were on the rise(p<.05). 2. Concerning the type of disability by year, there was an increase in the number of patients with brain lesions, mental retardation, developmental disorder and Down's syndrome(p<.05). As to the number of dental caries by the type of disability, the patients with heart diseases had the most dental caries that numbered 8.49, followed by Down's syndrome, metal retardation, brain lesions, the other disabilities and developmental disorder. 3. In relation to dental treatment experiences by the type of disability, the patients with developmental disorder(57.5%) received the most dental treatment, followed by mental retardation, the other disabilities, brain lesions, Down's syndrome and heart diseases(p<.05). 4. Regarding general anesthesia experience by the type of disability, the patients with mental retardation(31.6%) were put under general anesthesia the most, followed by developmental disorder, brain lesions, the other disabilities, heart diseases and Down's syndrome(p<.05). In conclusion, nationwide efforts to nurture separate dental personnels responsible for the disabled, to expand relevant facilities and to improve the health care insurance are required to promote the oral health of disabled children.

• Journal of Embryo Transfer
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• v.24 no.2
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• pp.115-119
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• 2009

In the present study, effects of concentration of cryoprotectant solutions on the nuclear maturation of vitrifiedthawed porcine oocytes were examined. Oocytes were cultured in TCM-199 medium supplemented with 5% FBS at $38^{\circ}$C in 5% $C0_2$ and air. The percentage of monospermy in the toxicity group and vitrification group (22.0 ${\pm}$ 3.0% and 31.5 ${\pm}$ 3.5%) was decreased compared with that of the control group (44.0 ${\pm}$ 4.0%). The percentage of in vitro development to blastocyst in the toxicity group and vitrification group (12.0 ${\pm}$ 2.5% and 14.8 ${\pm}$ 2.8%) was decreased compared with that of the control group (28.0 ${\pm}$ 3.0%, p<0.05). The survival and in vitro developmental rate of oocytes vitrification-thawed with EDS and EDT + TCM-199 medium supplemented with 0.1% PVA were 46.3 ${\pm}$ 3.0%, 54.5 ${\pm}$ 3.8% and 14.8 ${\pm}$ 2.5%, 16.4 ${\pm}$ 2.7%, respectively. This results were lower than the control group (28.0 ${\pm}$ 3.5%). The in vitro developmental rate of embryos vitrified with EDS and EDT supplemented PVA did not have a significant difference. The survival and in vitro developmental rate of vitrified-thawed morula and blastocyst embryos were 44.2 ${\pm}$ 3.5%, 17.3 ${\pm}$ 3.0% and 48.1 ${\pm}$ 4.2%, 18.5 ${\pm}$ 3.5%, respectively. Vitrified morulae and blastcyst embryos had a lower survival and developmental rates than their control counterparts.

• Clinical and Experimental Reproductive Medicine
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• v.20 no.1
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• pp.31-36
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• 1993

The effects of freezing and 1,2-propanediol on early and late pronucleate stage mouse ova were investigated in terms of survival after thawing and development in vitro. The samples were divided into two groups according to different age in pronucleate ova: ova in(1) early pronuclear stage with two distant pronuclei at 18h after hCG injection, and (2) late pronuclear stage with adjacent pronuclei at 30h. Zygotes in the late pronuclear stage have been proven to be more resistant to 1,2-propanediol, showing a significantly higher developmental rate than zygotes in early stage (80.3 versus 66.3%, <0.05), but survival rate was similar in the two groups (91.0 versus 93.5%). After freezing and thawing, survival and developmental rates were decreased in both groups when compared to the control group (54.3 versus 92.3%, 47.7 versus 73.3%. respectively). And developmental rate in the late pronuclear stage zygotes showed significantly higher than in early (55.4 versus 40.0%) after thawing. In conclusion, early pronucleate mouse ova have a lower developmental capacity in vitro and a lower survival rate after freezing and thawing than late ova. These findings suggest that the timing of freezing could be important for survival and further development in vitro in cryopreservation of human pronucleate ova.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.110-110
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• 2003

The high incidence of polyspermic fertilization is one of the major causes lowering the overall efficiency of porcine IVF. The common procedure for IVF involves the co-culture of both gametes in the medium drop, which increases sperm concentration and incidence of polyspermy. Therefore, the present study was carried out to increase the efficiency of porcine IVF by reducing polyspermy using a modified swim-up method. This method modifies conventional swim-up washing by placing oocytes directly at the time of washing. Sperm pellet was prepared in the tube and mature oocytes were placed on cell strainer with $70 \mu m$ pore size (Falcon 2350) at the top of the tube. After insemination, the oocytes were stained for examination. Also, the developmental potential of fertilized embryos was measured to evaluate for the feasibility of this method. While having similar penetration rates in both methods ($86.67 \pm 2.36% to 83.33 \pm 1.36%$), there was a significant reduction of polyspermy in modified swim-up method ($17.50 \pm 1.60%$) compare to the control ($44.1 \pm 3.70%$ (p<0.05). Subsequent culture showed higher rate of blastocyst formation in modified swim-up method (20.44$\pm$0.99%) than the control ($15.73 \pm 3.26%$) (P<0.05), even though there was no significant difference. These results suggest that, by controlling the number of spermatozoa reaching the oocytes, porcine oocytes might be protected from polyspermy in vitro. Also, the developmental potential of the fertilized embryos using this method could be improved by increasing the pool of spermatozoa with better quality. Further optimization of the procedure required to implicate this method in routine porcine IVF.

• Journal of Embryo Transfer
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• v.9 no.2
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• pp.145-152
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• 1994

The suitable electric stimulation is essential for activation and fusion of oocytes before or after nuclear transplantation The present study was undertaken to determine the optirnal condition for the parthenogenetic activation of in vitro rnatured(IVM) bovine oocytes by electric stimulation. Different direct current(DC) electric voltage of 1.0, 1.5 and 2.0 kV/cm and pulse duration of 30, 60 and 120 $\mu$sec were applied to the JVM nocytes in 0.3 M mannitol solution containing each 100 $\mu$M CaCl$_2$ and MgCl$_2$. IVM occytes at 24, 28 and 32 hours Post-maturation(hpm) were also electrically stimulated at 1.5 kV /cm, for 60 $\mu$ sec. The stimulated nocytes were then co-cultured in TCM-199 solution containing 10% fetal calf serum with bovine oviductal epithelial cells for 7~9 days in a 5% $CO_2$ incubator at 39$^{\circ}C$ ~ Their activation and in vitro development to morula and blastocyst were assessed under an inverted microscope. The higher activation rates 62.8 and 63.4% and in vitro de- velopment rates to morula and blastocyst 5.1 and 10.9% were shown in the oocytes stimulated at the voltage of 1.0 and 1.5 kV/cm than 2.0 kV/cm, respectively. No signifi- cantly(P<0.05) different activation rate was shown in JVM oocytes stimulated for 30, 60 and 120 $\mu$sec, but developmental rates to morula and blastocyst was significantly(P<0.05) higher in the oocytes stimulated for 30 $\mu$sec(6~3%) and 60 $\mu$sec(10~0%) than 120 $\mu$sec(0~ 0%). The aged oocytes at 28 and 30 hpm showed significantly(P<0.05) higher activation rates(72~7 and 79.7%) than the oocytes at 24 hpm(50~9%)~ Also, their developmental rates to morula and blastocyst were significantly(P<0.05) higher in the nocytes at 28(14.3%) and 32 hpm(15.9%) than 24 hpm(3.6%). From these results, it can be suggested that the optimal electric stimulation for IVM bovine occytes is a DC voltage between 1.0 and 1.5 kV/cm, pulse duration of 30 or 60 $\mu$sec, and the optimal age of IVM oocytes for electric activation is at 32 hpm.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.278-278
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• 2004

The purpose of this study was to establish the convenient freezing method for more cheap and simple. Semen quality was evaluated the motility, viability, abnormality, acrosome intactness and membrane integrity. And there were also examined the developmental rates of IVM/IVF embryos using frozen-thawed boar semen in each treatment group. (omitted)

• Development and Reproduction
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• v.17 no.4
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• pp.337-343
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• 2013

Post-thawed larval rearing in Pacific oyster Crassostrea gigas was performed to investigate the survival rate with time course in three kinds of larvae cryopreserved. The highest survival rate and larval activity index (LAI) of post-thawed larvae were obtained from the permeation in 0.2 M sucrose and 2.0 M ethylene glycol (EG) at $-1^{\circ}C/min$ in freezing speed showing the survival rates just after thawing of 63.8% in trochophore, 84.1% in D-shaped veliger and 56.3% in early umbo veliger. In post-thawed larval rearing with food supply, the larvae lasted their lives until 24 hours in trochophore, 75 hours in D-shaped veliger and 57 hours in early umbo veliger. The results suggested that each larval stage post-thawed revealed no more further development to subsequent respective stage.

• Korean Journal of Veterinary Research
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• v.30 no.2
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• pp.231-241
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• 1990

The present study was carried out to investigate the viability of frozen-thawed aggregated mouse embryos and to produce the chimeras. Different phenotypic embryos were obtained by mating ICR female mice with ICR or CBA male mice. The aggregated morulae were produced following aggregation of embryos at 4-, 8- and 12- to 16-cell stage. The desirable stage for the aggregation of the mouse embryos was 8- to 16-cell stage. The post-thawed in vitro survival rates of aggregated embryos in glycerol, DMSO and ethylene glycerol were 51.5, 78.6 and 69.4%, respectively. Although the higher survival was obtained in DMSO, there were no significant differences in the survival rates among the three cryoprotectants. A total of 155 frozen-thawed aggregated embryos were transferred to 11 recipient mice, 3 out of 7 offsprings were born to overt chimera. These experiments have proven that mouse chimeras can be obtained from frozen-thawed aggregated embryos.