• Journal of Veterinary Clinics
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• v.28 no.5
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• pp.486-496
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• 2011

A special mesenchymal tissue layer called perichondrium has a chondrogenic capacity and is a candidate tissue for engineering of cartilage. To overcome limited potential for chondrocyte proliferation and re-absorption, we studied a method of cartilage tissue engineering comprising chondrocyte-hydrogel pluronic complex (CPC) and cultured perichondrial cell sheet (cPCs) which entirely cover CPC. For effective cartilage regeneration, cell-sheet engineering technique of high-density culture was used for fabrication of cPCs. Hydrogel pluronic as a biomimetic cell carrier used for stable and maintains the chondrocytes. The human cPCs was cultured as a single layer and entirely covered CPC. The tissue engineered constructs were implanted into the dorsal subcutaneous tissue pocket on nude mice (n = 6). CPC without cPCs were used as a controls (N = 6). Engineered cartilage specimens were harvested at 12 weeks after implantation and evaluated with gross morphology and histological examination. Biological analysis was also performed for glycosaminoglycan (GAG) and type II collagen. Indeed, we performed additional in vivo studies of cartilage regeneration using canine large fullthickness chondrial defect model. The dogs were allocated to the experimental groups as treated chondrocyte sheets with perichondrial cell sheet group (n = 4), and chondrocyte sheets only group (n = 4). The histological and biochemical studies performed 12 weeks later as same manners as nude mouse but additional immunofluorescence study. Grossly, the size of cartilage specimen of cPCs covered group was larger than that of the control. On histological examination, the specimen of cPCs covered group showed typical characteristics of cartilage tissue. The contents of GAG and type II collagen were higher in cPCs covered group than that of the control. These studies demonstrated the potential of such CPC/cPCs constructs to support chondrogenesis in vivo. In conclusion, the method of cartilage tissue engineering using cPCs supposed to be an effective method with higher cartilage tissue gain. We suggest a new method of cartilage tissue engineering using cultured perichondrial cell sheet as a promising strategy for cartilage tissue reconstruction.

• Korean Journal of Veterinary Service
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• v.28 no.2
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• pp.121-146
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• 2005

Newcastle disease (ND), infectious bronchitis (IB), low pathogenic avian Influenza (LPAI) and fowl typhoid (FT) have been known as egg drop laying diseases because of the serious layer damage from mass zone layer. In this study, such egg drop laying diseases were investigated. To access this study, we peformed to evaluate antibody titers in serum and isolated bacteria and virus from organs and feces on May, July and September in 2003. The distribution of ND from January to May, IB and LPAI from October to February of the next year, and FT from March to September were inspected by the question survey in 21 farms. ND revealed to be positive rates of 490 to 474 $(96.7\%)$ in May, 510 to 506 $(99.2\%)$ in July and 510 to 510 $(100\%)$ in September with hemagglutination inhibition (HI) test. The mean antibody titers were 10.2, 9.9 and 10.2, respectively. With regard to IB, 484 out of 490 samples $(98.7\%)$ in May, 508 of 510 $(99.6\%)$ in July and 509 of 510 $(99.8\%)$ in September showed positive results and the mean antibody titers were gradually increased with 8.2, 9.0 and 9.4, respectively. According to HI test of LPAI, the positive results were shown in 442 of 480 $(92.1\%)$, 394 of 494 $(79.8\%)$ and 402 of 483 $(83.2\%)$ in May, July and September, respectively The mean antibody titers were decreased with 4.6, 4.3 and 4.0. The distribution of LPAI also elicited the positive rates of 480 to 475 $(99.0\%)$ in May, 494 to 485$(98.2\%)$ in July, 483 to 472 $(97.7\%)$ in September as determined by ELISA and the mean S/P ratio were 2.319, 2.557 and 2.380, respectively. Compared ELISA results with HI test of LPAI the positive results were 480 to 422 $(92.1\%),\;475(99.0\%),\;494\;to\;394 (79.8\%),\;485 (98.2\%)\;and\;483\;to\;402(83.2\%),\;472(97.7\%)$. Therefore, the positive rate determined by ELISA was higher than that of HI test with 6.9, 18.4 and $14.5\%$, respectively. When performed RT-PCR for ND using organ and feces samples, the pathotypes were detected $5(15.6\%)\;in\;May,\; 2(5.3\%) in\;July,\;2(7.1\%)$ in September but there is no samples showing positive band for LPAI. In attempt to isolate Salmonella gallinarum, bacteria were obtained from 4 cases (12.5%) in May, 9 (23.6%) in July, 5 (17.8%) in September. Thus the highest rate for isolation revealed to be shown in July When evaluated the antimicrobial susceptibility to 18 isolated strains of 5. gallinarum, bacteria were sensitive to trimethoprim/sulfamethox$(61.1\%),\;kanamycin\;(55.5\%),\;ampicillin\;(55.5\%)$ and amoxacillin/clavulanic acid $(55.5\%)$, cephalothin $(50.0\%)$, but resistant to penicillin $(88.9\%)$, streptomycin $(88.9\%)$, erythromycin $(83_4\%)$ and tetracycline $(61.1\%)$. According to HI test of ND and LPAI using captured 164 wild Korean tree sparrows (Passer nontanus), the positive rates were $47.6\%\;and\;57.3\%$, and the mean HI titers were 5.32 and 4.02, respectively. 71 $(43.2\%)\;and\;58(35.3\%)$ in captured sparrows also showed more than 4 titers for HI test to ND and LPAI, respectively However, the attempt for isolation of viruses failed in all samples.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.5 no.2
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• pp.174-180
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• 2002

Purpose: Ursodeoxycholic acid (UDCA) is known to decrease hepatic injury by promoting the biliary secretion of retained toxic endogenous bile acids in hepatobiliary diseases complicated by total parenteral nutrition (TPN). However, most studies have focused on treatment for complications after TPN. We investigated the preventive role of early administration of UDCA in TPN-induced hepatobiliary complications by a randomized, double-blind, placebo-controlled trial. Methods: Between May 2000 and May 2002, thirteen patients, who were given TPN more than 10 days in the hospital, were assigned randomly to two groups. One was the case group (7 patients) who were given UDCA simultaneously with TPN regimen, and the other, the control group (6 patients) who were given placebo. Their age ranged from 1 day to 13 years. They were affected with diseases impossible for enteral nutrition, such as prematurity, cerebral palsy, chronic diarrhea, anorexia nervosa, pancreatitis, and cyclic vomiting. The duration of TPN ranged from 10 to 70 days. Hematologic parameters including liver function test were measured at regular intervals, and the duration, composition, administration rate, total calorie of TPN were recorded. The serum levels of total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase were compared between groups after cessation of the study. Results: The autoregressive coefficient of the control group was 0.4419 (p=0.0651) in bilirubin, -0.0431 (p=0.7923) in AST, 0.2398 (p=0.2416) in ALT, and 0.2459 (p=0.1922) in alkaline phosphatase by mixed procedure model when the parameters were referred to the case group. Conclusion: The serum level of total bilirubin did not increase in comparison with that of the control group, but statistically insignificant, when both TPN and UDCA were administered simultaneously from the beginning.

• Pediatric Infection and Vaccine
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• v.4 no.2
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• pp.240-256
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• 1997

Purpose: To evaluate the hepatitis B vaccination program which has been conducted since 1980, Korea. Methods: This study was carry out self reported questionnaire and serologic test covering 2,072 elementary school students who were born between 1980 and 1987, selected by cluster sampling. The HBV serologic markers (HBsAg, Anti-HBs and Anti-HBc) were tested by radioimmunoassay (RIA). The contents of questionnaire include demographic data of students and parents, vaccination status, vaccination frequency, vaccination age, past history of mother's HBV test. Results: 1) The HBsAg positive rates by sex showed 3.7% for male and 2.7% for female, representing an average rate of 3.4%. The HBsAg positive rates by age group showed 5.6% for 13 years and l.5% for 6 years, representing a tendency of lowering rate as ages being younger. 2) The pre-natal HBV test rate was 10.2%, while post-natal HBV test rate was 42.5%. The test showed that the parents' educational level being higher than others, the pre- and post-natal HBV test showed higher rates. In case the fathers occupation being office worker, the post-natal HBV test showed a higher rate compared with other occupation. 3) Overall vaccination rate was 82.6%, complete vaccination rate 69.8%, booster injection rate 42.8%. The vaccination rate, complete vaccination rate and booster injection rate increased as the age being younger. If the educational level of parents were higher, the vaccination rate, complete vaccination rate and booster injection rate showed higher rates. Younger students showed younger vaccination age, and higher educational background of family showed younger vaccination ages. 4. With regard to positive rate of HBV markers by vaccination age, HBsAg and Anti-HBc positive rate showed higher degrees in the following order; preschool age (1-6 years), school age (6-13 years) and infancy (0-1 year). Anti-HBs positive rate was increased as the frequency of vaccination increased. Five years after initial complete vaccination, minimum protective rate was lowest, 69.6%.

• Pediatric Infection and Vaccine
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• v.4 no.2
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• pp.232-239
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• 1997

Purpose: The incidence of hepatitis A virus(HAV) infection has markedly decreased in the last 20 years due to industrialization and improvements in the standard of living and hygiene in Korea. The reduction in seroprevalence rates indicates infection potential for young adult population, and a need for vaccinations in high-risk adults and children groups has been suggested. In this study we evaluated the seroprevalence rates and natural infection rates of hepatitis A in children and adolescent to obtain the basic data for vaccination of hepatitis A. Methods: A total of 334 children and adolescent subjects below 20 years old in Kyonggi-do province were examined for HAV antibody and seroprevalence rates in each age group was investigated. In 584 elementary school students residing in Kyonggi-do province, serum samples collected in 1993 and 1996 from the same subjects for investigation of natural seroconversion rates. Method of testing antibody was enzyme immunoassay. Results: 1) The seropositive rate of HAV in 334 subjects aged below 20 years old was 5.4%. According to age, the seropositive rates were 27.3% in infant group, 0.0% in 1~4 year-old group, 0.0% in 5~9 year-old group, 2.9% in 10~14 year-old group and 15.0% in 15~19 year-old group. 2) In the study of 584 elementary school children, only one subject showed seropositive in 1993, and in 1996 three different subjects showed seropositive results(0.5%); the natural seroconversion rate during 3 years was 0.5%. 3) The seroprevalence rates of below 20 year-old subjects reported in previous studies were 63.8% in 1979 and 47.3% in 1989 while the present study showed the rate at 5.4%. Conclusion: Since natural antibody formation is rarely occurring, there is a high risk for apparent hepatitis A infection in adults. Therefore vaccination in high risk groups is essential at present, and in order to reduce the chance for hepatitis A infection in adults, vaccination in children may be needed.

• Molecules and Cells
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• v.21 no.1
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• pp.52-62
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• 2006

In previous reports we demonstrated that ginsenosides, active ingredients of Panax ginseng, affect some subsets of voltage-dependent $Ca^{2+}$ channels in neuronal cells expressed in Xenopus laevis oocytes. However, the major component(s) of ginseng that affect cloned $Ca^{2+}$ channel subtypes such as ${\alpha}_{1C}$(L)-, ${\alpha}_{1B}$(N)-, ${\alpha}_{1A}$(P/Q)-, ${\alpha}_{1E}$(R)- and ${\alpha}_{1G}$(T) have not been identified. Here, we used the two-microelectrode voltage clamp technique to characterize the effects of ginsenosides and ginsenoside metabolites on $Ba^{2+}$ currents ($I_{Ba}$) in Xenopus oocytes expressing five different $Ca^{2+}$ channel subtypes. Exposure to ginseng total saponins (GTS) induced voltage-dependent, dose-dependent and reversible inhibition of the five channel subtypes, with particularly strong inhibition of the ${\alpha}_{1G}$-type. Of the various ginsenosides, $Rb_1$, Rc, Re, Rf, $Rg_1$, $Rg_3$, and $Rh_2$, ginsenoside $Rg_3$ also inhibited all five channel subtypes and ginsenoside $Rh_2$ had most effect on the ${\alpha}_{1C}$- and ${\alpha}_{1E}$-type $Ca^{2+}$ channels. Compound K (CK), a protopanaxadiol ginsenoside metabolite, strongly inhibited only the ${\alpha}_{1G}$-type of $Ca^{2+}$ channel, whereas M4, a protopanaxatriol ginsenoside metabolite, had almost no effect on any of the channels. $Rg_3$, $Rh_2$, and CK shifted the steady-state activation curves but not the inactivation curves in the depolarizing direction in the ${\alpha}_{1B}$- and ${\alpha}_{1A}$-types. These results reveal that $Rg_3$, $Rh_2$ and CK are the major inhibitors of $Ca^{2+}$ channels in Panax ginseng, and that they show some $Ca^{2+}$ channel selectivity.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.99-128
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• 2018

The cultivation area of rice as staple grains is decreasing in the domestic situation in Korea. Import volume of a duty in foreign rice is 409,000 tons for a year regardless increasing of production per unit area and decreasing of rice consumption. The total stock of rice is increasing cumulatively despite the effort for production mediation of rice. Therefore, maintenance of cultivation area and reduction of production are necessary for national foodstuffs security problems. Development of environment-friendly and low-carbon technology as alternative of global warming and aging of farm labor power is very important responsibility for descendants with creation of sustainable agriculture environment. As alternative for demand and supply stabilization of rice from all angles, first stage: extension of environment-friendly cultivation area as 17% Jeollanam-do level with maintenance of cultivation area under the present circumstances, second stage: extension of environment-friendly cultivation area as 25%, third stage: extension of environment-friendly cultivation area as 35%. From above mentioned scenario, reduction of rice production (60,000 tons), increases of production cost (59,200,000,000 Won), and reduction of income (201,500,000,000 Won) are estimated in first stage. Reduction of rice production (90,000 tons), increases of production cost (122,100,000,000 Won), and reduction of income (313,700,000,000 Won) are estimated in second stage. Reduction of rice production (380,000 tons), increases of production cost (222,000,000,000 Won), and reduction of income (464,500,000,000 Won) are estimated in third stage. From analysis results for partial tillage in transplanting cultivation complex (10ha), rice production is decreased 1.3~1.5 ton by complex. Production cost of rice is decreased and increases of income cultivation type. Gradual extension of environment-friendly agriculture and low-carbon partial tillage could be expected for environment maintenance of the territorial integrity, confidence of consumer, and high-efficiency of low-cost.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.4
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• pp.302-307
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• 2014

To examine the trophic ecology of the ascidian Styela clava in an aquaculture system of Korea, stable carbon and nitrogen isotopes were analyzed monthly in S. clava, coarse ($>20{\mu}m$, CPOM) and fine particulate organic matters ($0.7<<20{\mu}m$, FPOM). CPOM (means: $-18.5{\pm}1.2$‰, $9.3{\pm}0.7$‰) were significantly higher ${\delta}^{13}C$ and ${\delta}^{15}N$ values than those ($-20.5{\pm}1.5$‰, $8.4{\pm}0.5$‰) of FPOM. S. clava had mean ${\delta}^{13}C$ and ${\delta}^{15}N$ values of $-18.9({\pm}1.7)$‰ and $11.6({\pm}0.7)$‰, respectively. S. clava were more similar to seasonal variations in ${\delta}^{13}C$ and ${\delta}^{15}N$ values of FPOM than those of CPOM, suggesting that they rely largely on the FPOM as a dietary source. In addition, our results displayed that the relative importance between CPOM and FPOM as dietary source for the ascidians can be changed according to the availability of each component in ambient environment, probably reflecting their feeding plasticity due to non-selective feeding irrespective of particle size. Finally, our results suggest that dynamics of pico- and nano-size plankton (i.e., FPOM) as an available nutritional source to S. clava should be effectively assessed to maintain and manage their sustainable aquaculture production.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.4
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• pp.255-264
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• 2003

A study was conducted to determine the effects of pig slurry application on forage yield and growth of fazing Hanwoo heifer in a mixed pasture. To each of three treatments 1.4ha were alloted a control applied with only chemical fertilizer (N-P-K=150-150-120kg/ha), two pig slurry lots applied with the amount to allow 100% (150 kg/ha) or 150% (225 kg/ha) of N used in the control. A randomized block design was used without replication. Cattle were allowed to graze continuously during the experimental period. Results obtained were as follows: Total dry matter yield was 16,291, 15,632 and 16,320 kg/ha for chemical fertilizer. pig slurry 100% and 150％, respectively. The pasture was dominated by perenial ryegrass during the first gazing season, but by orchard grass and perenial ryegrass (60∼70%) and red clover (20∼30%) during the second grazing season. Average gazing rate per ha was 2.75∼2.76 animal units and daily weight gain of grazing cattle was not different among treatments ranging from 0.563 to 0.580 kg. Total weight gain of grazing cattle per ha during the grazing period was 541, 541 abd 555 kg for chemical fertilizer, pig -slurry 100 and 150%, respectively. RBC, WBC, total protein and albumin etc. concentrations in blood were normal in all treatments.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.245-251
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• 2013

These experiments are being conducted to obtain data of plant height, panicle length, heading date, number of culm, and fresh and dry weight, crude protein, acid detergent fiber (ADF), neutral detergent fiber (NDF), total digestible nutrients (TDN) by six times seeding of 10 days interval ranging from May 1st to June 21st for two types of barnyard millet from the Suwon area in Korea. In the early-heading type, IT 170609 (Echinochloa crus-galli), the plant height and the number of culm per square meters are decreased by late seeding relatively, and heading date is 7 to 10 days earlier than the late seeding. And the dry weight of forage is rapidly decreased after the June 11th seeding. In the late-heading type, IT 195422 (Echinochloa frumentacea), the plant height and the number of culm per square meters are also decreased by late seeding relatively, and heading date is about 13 days earlier than late seeding. The dry weight of forage was rapidly decreased after the June 11th seeding. In both two types, the nutritive value of ADF, NDF, and TDN are not changed by late seeding, but crude protein is increased by late seeding. The TDN yields of late-heading type, IT 195400, show average amounts in the June 1st seeding, but the TDN yield of early-heading type, IT 170606, indicate safety amounts of dry weight to the March 21st seeding. And these data are available for cropping systems, cultivating barnyard millet in summer and cereals for forage in winter, to get high production of forage in Korea.