• Restorative Dentistry and Endodontics
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• 제24권2호
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• pp.299-309
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• 1999

The composite resin, due to its esthetic qualities, is considered the material of choice for restoration of anterior teeth. With respect to shade control, the direct-placement resin composites offer some distinct advantages over indirect restorative procedures. Visible-light-cured (VLC) composites allow dentists to match existing tooth shades or to create new shades and to evaluate them immediately at the time of restoration placement. Optimal intraoral color control can be achieved if optical changes occurring during application are minimized. An ideal VLC composite, then, would be one which is optically stable throughout the polymerization process. The shade guides of the resin composites are generally made of plastic, rather than the actual composite material, and do not accurately depict the true shade, translucency, or opacity of the resin composite after polymerization. So the numerous problems associated with these shade guides lead to varied and sometimes unpredictable results. The aim of this study was to assess the color changes of current resin composite restorative materials which occur as a result of the polymerization process and to compare the color differences between the shade guides provided with the products and the actual resin composites before- and after-polymerization. The results obtained from this investigation should provide the clinician with information which may aid in improved color match of esthetic restoration. Five light activated, resin-based materials (${\AE}$litefil, Amelogen Universal, Spectrum TPH VeridonFil-Photo, and Z100) and shade guides were used in this study. Three specimens of each material and shade combination were made. Each material was condensed inside a 1.5mm thick metal mold with 10mm diameter and pressed between glass plates. Each material was measured immediately before polymerization, and polymerized with Curing Light XL 3000 (3M Dental products, USA) visible light-activation unit for 60 seconds at each side. The specimens were then polished sequentially on wet sandpaper. Shade guides were ground with polishing stones and rubber points (Shofu) to a thickness of approximately 1.5mm. Color characteristics were performed with a spectrophotometer (CM-3500d, Minolta Co., LTD). A computer-controlled spectrophotometer was used to determine CIELAB coordinates ($L^*$, $a^*$ and $b^*$) of each specimen and shade guide. The CIELAB measurements made it possible to evaluate the amount of the color difference values (${\Delta}E{^*}ab$) of resin composites before the polymerization process and shade guides using the post-polishing color of the composite as a control, CIE standard D65 was used as the light source. The results were as follows. 1. Each of the resin composites evaluated showed significant color changes during light-curing process. All the resin composites evaluated except all the tested shades of 2100 showed unacceptable level of color changes (${\Delta}E{^*}ab$ greater than 3.3) between pre-polymerization and post-polishing state. 2. Color differences between most of the resin composites tested and their corresponding shade guides were acceptable but those between C2 shade of ${\AE}$litefil and IE shade of Amelogen Universal and their respective shade guides exceeded what is acceptable. 3. Comparison of the mean ${\Delta}E{^*}ab$ values of materials revealed that Z100 showed the least overall color change between pre-polymerization and post-polishing state followed by ${\AE}$litefil, VeridonFil-Photo, Spectrum TPH, and Amelogen Universal in the order of increasing change and Amelogen Universal. Spectrum TPH, 2100, VeridonFil-Photo and ${\AE}$litefil for the color differences between actual resin and shade guide. 4. In the clinical environment, the shade guide is the better choice than the shade of the actual resin before polymerization when matching colors. But, it is recommended that custom shade guides be made from resin material itself for better color matching.

• 한국수정란이식학회지
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• 제27권2호
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• pp.113-119
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• 2012

Epigenetic modification including genome-wide DNA demethylation is essential for normal embryonic development. Insufficient demethylation of somatic cell genome may cause various anomalies and prenatal loss in the development of nuclear transfer embryos. Hence, the source of nuclear donor often affects later development of nuclear transfer (NT) embryos. In this study, appropriateness of porcine embryonic germ (EG) cells as karyoplasts for NT with respect to epigenetic modification was investigated. These cells follow methylation status of primordial germ cells from which they originated, so that they may contain less methylated genome than somatic cells. This may be advantageous to the development of NT embryos commonly known to be highly methylated. The rates of blastocyst development were similar among embryos from EG cell nuclear transfer (EGCNT), somatic cell nuclear transfer (SCNT), and intracytoplasmic sperm injection (ICSI) (16/62, 25.8% vs. 56/274, 20.4% vs. 16/74, 21.6%). Genomic DNA samples from EG cells (n=3), fetal fibroblasts (n=4) and blastocysts from EGCNT (n=8), SCNT (n=14) and ICSI (n=6) were isolated and treated with sodium bisulfite. The satellite region (GenBank Z75640) that involves nine selected CpG sites was amplified by PCR, and the rates of DNA methylation in each site were measured by pyrosequencing technique. The average methylation degrees of CpG sites in EG cells, fetal fibroblasts and blastocysts from EGCNT, SCNT and ICSI were 17.9, 37.7, 4.1, 9.8 and 8.9%, respectively. The genome of porcine EG cells were less methylated than that of somatic cells (p<0.05), and DNA demethylation occurred in embryos from both EGCNT (p<0.05) and SCNT (p<0.01). Interestingly, the degree of DNA methylation in EGCNT embryos was approximately one half of SCNT (p<0.01) and ICSI (p<0.05) embryos, while SCNT and ICSI embryos contained demethylated genome with similar degrees. The present study demonstrates that porcine EG cell nuclear transfer resulted in hypomethylation of DNA in cloned embryos yet leading normal preimplantation development. Further studies are needed to investigate whether such modification affects long-term survival of cloned embryos.

• Asian-Australasian Journal of Animal Sciences
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• 제21권4호
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• pp.547-554
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• 2008

In performance, digestibility and slaughter trials, a total of forty five male weaned lambs were used to examine the effects of monensin and live yeast supplementations on growth performance, nutrient digestibility, carcass characteristics and ruminal fermentation parameters when the lambs were fed steam-flaked corn-based diets. Animals were allotted to one of three treatment diets in a completely randomized design. The three treatment diets were: (1) basal diet (CON) with steam-flaked corn as a sole grain source, (2) basal diet supplemented with monensin (MO), and (3) basal diet supplemented with live yeast (LY). Total average daily intake (ADI) was unaffected by MO and LY supplementations. LY supplementation increased (p<0.05) average daily gain (ADG) by 13.1% compared with the CON diet. Both MO and LY supplementations resulted in a significant improvement (p<0.05) of feed efficiency over the CON diet (4.47, 4.68 vs. 5.05). Hemicellulose digestibility was higher (p<0.05) for lambs in the LY supplementation group (62.4%) as compared with the CON group (55.7%), but no differences were observed in digestibilities of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF). All carcass traits were not influenced by dietary supplementations. Ruminal pH in lambs fed the LY supplemental diet was more stable than that with the CON diet (6.57 vs. 6.17). Neither MO nor LY supplementation influenced the concentration of ruminal ammonia-N and total volatile fatty acid (VFA), and molar percentages of individual VFA. Plasma urea-N concentration was decreased (p<0.05) by MO and LY supplementations, while plasma ${\beta}$-hydroxybutyrate (BHBA), glucose and other blood parameters were unaffected. In conclusion, while both MO and LY supplementations had a positive impact on feed efficiency and LY supplementation stabilized ruminal pH and improved fiber utilization, none of the supplements had the capacity to significantly enhance the carcass characteristics.

• 식물병연구
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• 제10권4호
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• pp.217-226
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• 2004

한 중 벼 도열병균의 특성 검정과 저항성원의 공동 평가를 통하여 병원균의 특성을 구명하고 주요 저항성원에 대한 정보와 한국 도열병균의 분화 현상이 중국으로부터 유래하였는지를 분석하였다. 각국의 대표균주 각각 100균주씩을 한국, 중국 판별품종 및 단인자 저항성 품종에 접종한 결과, 한국 병원균은 중국 단인자 저항성 품종에서 29개의 반응형을 보였으며, 한국균주 46%가 중국 NIL(LTH/일본품종 저항성 유전자)을 모두 침해하여, 우리나라 벼 육종 시 저항성원으로 적합지 않은 것으로 나타났다. 또한 한국판별품종에 대한 중국균주의 반응결과, KJ-201, KJ-301, KJ-403, KJ-105, KJ-101 레이스가 각각 11%, 10%, 9% , 8%, 7%의 비율로 나타났다. 그러나 RFLP-MGR586 profile은 한국 균주가 중국균주보다 band 수와 양상이 다양하여 변이가 심한 것으로 나타났으며, IRRI에서 육성한 11개의 단인자 저항성 품종에 대하여 한-중균주의 유전자 침해비율은 대체로 비슷한 경향이었다. Pi-z, Pi-3, Pi-5(t)는 한국 균주가 각각 56.6%, 58.1%, 45.4%침해하는 반면, 중국 균주는 각각 85.2%, 75.9%, 75.9%를 침해하여 중국 균주의 침해 비율이 높았고 Pi-b 유전자의 경우, 한국 균주의 82.6%가 침해하는 반면 중국 균주는 59.3%가 침해하여 한국 균주의 침해 비율이 높았다.

• 한국의학물리학회지:의학물리
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• 제15권2호
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• pp.105-111
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• 2004

본 연구에서는 의료용 선형가속기로부터 발생되는 명목상 가속전압 6 MV선의 검출특성을 확인하기 위하여 유전체 물질을 사용한 평행판 검출기를 제작하였다. 제작한 검출기의 전극은 단면이 크롬으로 코팅되어 있는 FEP유전체 필름(두께: 100 $\mu\textrm{m}$)을 사용하였고 두 전극 사이에 PTFE유전체 필름(두께 : 100 $\mu\textrm{m}$)을 삽입하였다. 측정을 위하여 선원-팬텀 표면간의 거리 100 cm, 그리고 팬텀의 표면으로부터 깊이 5 cm되는 지점에 방사선 유도전하를 획득하기 위한 제작검출기를 놓았다. 방사선 조사시 제작검출기의 유용성을 알아보기 위하여, 영점 변동, 누설 전류, 인가전압에 따른 검출기의 반응, 재현성, 선형성, 조직최대선량비 등을 측정하였다. 측정결과 검출기의 영점 변동 전류 (I$_{Z}$ )는 8.3 pA, 누설 전류(I$_{I}$)는 10 pA 이었다. 제작 검출기는 인가전압에 대한 선형성을 보였으며, 또한 재현성실험에서는 조사된 선량에 대하여 1% 오차 범위 내에서 일치하였다. 검출기의 선량에 대한 선형성은 3% 이내의 오차범위에서 일치하면서 선량율 의존성이 있음을 확인하였다. 조직최대선량비분포에 대한 제작 평행판 검출기와 비교검출기간의 선량오차는 팬텀내의 최대 선량점으로부터 7.5 cm까지 3% 이내에서 일치하였다. 본 연구결과 유전체 필름을 이용한 평행판 검출기는 선량계로서의 기본적인 특성들을 허용 가능한 범위에서 만족스러워 상대선량측정을 위한 검출기로 사용할 수 있음을 확인할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권5호
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• pp.661-671
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• 2006

Steers (n = 335) of known genetic backgrounds from four fundamentally different growth types were subjected to two production systems to study the main effects and possible interactive effects on carcass composition. Growth types were animals with genetic potential for large mature weight (LL), intermediate mature weight-late maturing (IL), intermediate mature weight-early maturing (IE), and small mature weight-early maturing (SE). Each year, in a nine year study, calves of each growth type were weaned and five steers of each growth type were developed on pasture or feedlot and harvested at approximately 20 and 14 mo of age, respectively. Data recorded were chilled carcass weight and percentages of forequarter, foreshank, chuck, rib, plate, brisket, hindquarter, round, rump, shortloin, sirloin, flank, lean, fat, bone, and retail cuts. The growth $type{\times}production$ system interaction was an important source of variation in chilled carcass weight (p = 0.0395) and percentage retail cuts (p = 0.001), lean (p = 0.001), fat (p = 0.001), rump (p = 0.0454), shortloin (p = 0.0487), and flank (p = 0.001). The ranking of the growth $type{\times}production$ system means for percentage lean was LL-pasture>IL-pasture = IE-pasture = SE-pasture>LL-feedlot, IL-feedlot>IE-feedlot = SE-feedlot. The growth $type{\times}production$ system interaction was non-significant (p>0.05) for forequarter, foreshank, chuck, rib, plate, brisket, hindquarter, round and bone. Growth types of IE and SE yielded greater (p<0.05) mean forequarter than did growth types of IL and LL ($51.6{\pm}0.3$ and $51.5{\pm}0.3$ vs. $51.1{\pm}0.3$ and $50.8{\pm}0.3%$). Mean bone was highest (p<0.05) for the LL growth type and lowest (p<0.05) for the SE growth type ($19.5{\pm}0.5$ vs. $16.8{\pm}0.5%$). Mean bone was greater (p<0.05) for the pastured steers than for the feedlot steers ($21.8{\pm}0.8$ vs. $14.5{\pm}0.6%$). These data indicate that growth type responded differently in the two production systems and that these results should be helpful in the match of genetics to production resources.

• Fisheries and Aquatic Sciences
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• 제19권3호
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• pp.14.1-14.10
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• 2016

Isoelectric solubilization/precipitation (ISP) processing allows selective, pH-induced water solubility of proteins with concurrent separation of lipids and removal of materials not intended for human consumption such as bone, scales, skin, etc. Recovered proteins retain functional properties and nutritional value. Four roe protein isolates (RPIs) from yellowfin tuna roe were prepared under different solubilization and precipitation condition (pH 11/4.5, pH 11/5.5, pH 12/4.5 and pH 12/5.5). RPIs contained 2.3-5.0 % moisture, 79.1-87.8 % protein, 5.6-7. 4 % lipid and 3.0-3.8 % ash. Protein content of RPI-1 and RPI-2 precipitated at pH 4.5 and 5.5 after alkaline solubilization at pH 11, was higher than those of RPI-3 and RPI-4 after alkaline solubilization at pH 12 (P < 0.05). Lipid content (5.6-7.4 %) of RPIs was lower than that of freeze-dried concentrate (10.6 %). And leucine and lysine of RPIs were the most abundant amino acids (8.8-9.4 and 8.5-8.9 g/100 g protein, respectively). S, Na, P, K as minerals were the major elements in RPIs. SDS-PAGE of RPIs showed bands at 100, 45, 25 and 15 K. Moisture and protein contents of process water as a 2'nd byproduct were 98.9-99.0 and 1.3-1.8 %, respectively. Therefore, yellowfin tuna roe isolate could be a promising source of valuable nutrients for human food and animal feeds.

• 한국식품영양과학회지
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• 제37권9호
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• pp.1095-1100
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• 2008

국내산 밤 일부 품종(단택, 대보, 석추, 옥광, 병고)의 기능성 성분 분석과 이들 물질들의 항산화력 및 밤 추출물이 대식세포 활성에 미치는 영향력을 알아보았다. 국내산 밤 일부 품종의 내피와 과육에서 coumarin, gallic acid 그리고 catechin이 HPLC에 의해 검출되었다. 밤 내피에 가장 풍부한 기능성 성분은 catechin이고 그 다음 gallic acid와 coumarin 순이었으나, 과육에서는 gallic acid만 검출되었다. 따라서 밤의 기능성 성분인 gallic acid와 catechin의 항산화력을 DPPH radical 소거작용과 SOD 유사활성을 통해 알아보았다. Gallic acid과 catechin을 6.0 mg/100 g 처리하였을 때 DPPH radical 소거작용이 각각 69.4%와 38.3%였으며, gallic acid의 DPPH radical 소거작용은 농도 의존적이었다. Gallic acid를 동일한 농도의 catechin과 비교하면 모든 농도 구간에서 catechin보다 gallic acid가 높은 DPPH radical 소거활성을 나타내었다. 그러나 SOD 유사활성은 gallic acid보다 catechin이 높았다. 더하여 밤의 과육, 노란과육 및 흰과육 추출물들이 대식세포 활성에 미치는 영향력을 알아보았다. 병고 흰과육 추출물은 현저하게 대식세포 활성을 증가시켰고, 병고, 단택, 대보 및 옥광의 노란과육 추출물 역시 아무 것도 처리하지 않은 세포와 비교하여 현저히 대식세포를 활성화시켰다. 노란과육 추출물이 흰과육 추출물보다 더욱 더 대식세포 활성을 증가시켰고, 5품종 중 병고가 대식세포 활성을 가장 증가시켰다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권1호
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• pp.86-94
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• 2015

This experiment was conducted to evaluate the chemical composition and amino acid (AA) digestibility of sunflower seed meal (SFSM) and to use this data to develop prediction equations for estimating AA digestibility for growing pigs. Ten SFSM were collected from five provinces in China. Twelve barrows ($38.8{\pm}4.6kg$), fitted with ileal T-cannula were allotted into two $6{\times}6$ Latin square designs. Each of six experimental periods comprised a 5-d adaption period followed by a 2-d collection of ileal digesta. The ten test diets contained 50% SFSM as the sole source of AA. Another nitrogen-free diet was used to measure the basal endogenous losses of crude protein (CP) and AA. Chromic oxide (0.3%) was used as an inert marker in each diet. There was considerable variation (CV>10%) among the ten SFSM in chemical composition (dry matter [DM]). The concentration of CP and ether extract (EE) ranged from 29.33% to 39.09% and 0.88% to 11.33%, respectively. Crude fibre (CF), neutral detergent fibre and acid detergent fibre ranged from 21.46% to 36.42%, 38.15% to 55.40%, and 24.59% to 37.34%, respectively. There was variation among the ten SFSM in apparent ileal digestibility (AID) and standardized ileal digestibility (SID) for lysine and threonine, which ranged from 63.16 to 79.21 and 55.19% to 72.04% for AID and 67.03% to 82.07% and 61.97% to 77.01% for SID, respectively. The variation in CP and methionine ranged from 60.13% to 74.72% and 74.79% to 88.60% for AID and 66.70% to 79.31% and 77.16% to 90.27% for SID, respectively. Methionine was a good indicator to predict AA digestibility. These results indicate that conventional chemical composition of SFSM was variable (CV>10%) among the ten SFSM (DM). The results of AID, SID and prediction equations could be used to evaluate the digestibility of SFSM in growing pigs.

• Asian-Australasian Journal of Animal Sciences
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• 제10권1호
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• pp.79-85
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• 1997

Cage layer waste and sudex grass were ensiled in the proportions of 0:100, 30:70, 40:60 and 50:50 wet basis, respectively. The influence of ensiling cage layer waste on Salmonellae, Shigella, Proteus, and total number of colony forming units (CFU) was investigated. The nutritive value of the silages was evaluated in a digestion trial. The experiment was conducted with 24 wethers allotted to four silages. Initial samples of cage layer waste showed $0.11{\times}10^6$ CFU and salmonellae, Shigella and Proteus were present. Ensiling was effective in complete elimination of all the pathogens. Dry matter, crude protein and ash contents were increased linearly (p < .01) with the increase of cage layer waste in the silages ($358g{\cdot}kg^{-1}$ to $484g{\cdot}kg^{-1}$; $76.3g{\cdot}kg^{-1}$ to $183.2g{\cdot}kg^{-1}$ and $38.5g{\cdot}kg^{-1}$ to $169.4g{\cdot}kg^{-1}$; DM basis, respectively). Water solubles carbohydrate values for silages were 38.3, 22.5, 20.1 and $20.0g{\cdot}kg^{-1}$ DM basis, respectively. Ensiling decreased the pH values for all the silages and the decrease was higher for sudex grass ensiled alone than grass ensiled with cage layer waste. Lactic acid concentration in silages increased linearly (p < .01) with the increase of cage layer waste. The apparent digestibilities of DM, OM and CP for the animals fed sudex grass silage alone were 496.0, 516.1, $496.7g{\cdot}kg^{-1}$ DM basis respectively. However, digestibilities of all the components were higher (p < 0.01) for the animals fed silages containing cage layer waste. Among waste containing diets, the digestibilities of all the components showed quadratic affect (p < 0.01), increased for silages containing 30 and 40% cage layer waste and decreased when the level of waste increased from 40 to 50%. The results indicated that cage layer waste can be used upto 40% in ruminant diet as a source of N without any adverse effect on the health of animals. Ensiling appeared to be feasible and effective method for eliminating the pathogen present in cage layer waste.