• 한국수정란이식학회지
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• 제33권4호
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• pp.265-270
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• 2018

Up-to-date artificial insemination (AI) using frozen sperm consider as the most widely using technology for improvement of Korean Native Cow (Hanwoo) embryo production. However, it is time consuming, required at least 15~20 years to make more than 6 generations, and their offspring number is limited. To overcome such limitations, superovulation and in vitro fertilization have been developed. For superovulation, the number of produced embryos are not enough for commercialization and donor cows need rest period. This led to use of slaughterhouse ovary for in vitro fertilization, but it is impossible to repeat the collection from the same individual and it only can improve the genetic merits of offspring for one generation. Production of embryos using Ovum Pick-Up (OPU) technique, where oocytes can be repeatedly collected from living elite donor, might overcome these limitations. In this study, we investigated the possibility of using OPU technique from donors at different age and different session periods for mass-embryo-production. Oocytes were collected from 26 donor cows twice per week, 3 - 4 months per year, between 2013 and 2016. Results showed that, the average number of embryo produced in first year used donor was significantly higher than that in second year used donor ($3.89{\pm}2.85$ vs $3.29{\pm}2.70$), however, there was no significant difference between third year used donor ($3.51{\pm}3.32$) and other groups. Taken together, our data showed that repeated using of donor up to three years is possible for in vitro embryo mass-production. Moreover, OPU can be used as suitable embryo producing technique for livestock breed improvement.

• 한국산림과학회지
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• 제82권3호
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• pp.254-259
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• 1993

이병묘로부터 마이코플라즈마 무병주의 생산법을 확립하기 위하여 대추나무 시험관묘의 액아에서 생장점을 채취하여 기내접목을 실시하였다. 대목으로는 기내에서 발아시킨 대추나무 실생묘의 배축을 사용하였다. 접수중 10%(30점 중 3점씩 2회)가 정상적으로 생장하였고 계속적인 증식과 발근이 가능하여 유식물체로 분화되었다. 마이코플라즈마의 존재여부를 전자현미경과 형광현미경 검경방법을 이용하여 검경한 결과, 접수로 사용한 시험관묘에서는 마이코플라즈마가 관찰되었으나 접목묘에서는 관찰되지 않았다. 이로써 마이코플라즈마를 보균한 시험관묘의 생장점을 접수로 한 기내 미세접목을 통하여 건전묘 생산의 가능성을 보여주었다.

• Journal of Periodontal and Implant Science
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• 제53권5호
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• pp.388-401
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• 2023

Purpose: This study investigated the accuracy of free-hand implant surgery performed by an experienced operator compared to static guided implant surgery performed by an inexperienced operator on an anterior maxillary dental model arch. Methods: A maxillary dental model with missing teeth (No. 11, 22, and 23) was used for this in vitro study. An intraoral scan was performed on the model, with the resulting digital impression exported as a stereolithography file. Next, a cone-beam computed tomography (CBCT) scan was performed, with the resulting image exported as a Digital Imaging and Communications in Medicine file. Both files were imported into the RealGUIDE 5.0 dental implant planning software. Active Bio implants were selected to place into the model. A single stereolithographic 3-dimensional surgical guide was printed for all cases. Ten clinicians, divided into 2 groups, placed a total of 60 implants in 20 acrylic resin maxillary models. Due to the small sample size, the Mann-Whitney test was used to analyze mean values in the 2 groups. Statistical analyses were performed using SAS version 9.4. Results: The accuracy of implant placement using a surgical guide was significantly higher than that of free-hand implantation. The mean difference between the planned and actual implant positions at the apex was 0.68 mm for the experienced group using the free-hand technique and 0.14 mm for the non-experienced group using the surgical guide technique (P=0.019). At the top of the implant, the mean difference was 1.04 mm for the experienced group using the free-hand technique and 0.52 mm for the non-experienced group using the surgical guide technique (P=0.044). Conclusions: The data from this study will provide valuable insights for future studies, since in vitro studies should be conducted extensively in advance of retrospective or prospective studies to avoid burdening patients unnecessarily.

• 한국작물학회지
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• 제45권1호
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• pp.32-37
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• 2000

The in vitro culture of rice panicles is a culturing technique only panicle without other organs in culture solution containing organic substance, so that would be useful to study how assimilate supply affects grain development and maturation. To find the optimum stage for in vitro culture, rice panicles grown in greenhouse were sampled periodically after anthesis and cultured in nutrient medium. The panicles older than 1 weeks after anthesis had produced normal grains. Grain-filling was apparently dependent upon sucrose concentration (8-12 %) in medium, but not affected by nitrogen concentration supplied with glutamine. As far as rice panicle was supplied with sucrose and N in nutrient medium, grains continued accumulation of dry matter and maturation regardless to light condition. Considerably, grain-filling was improved when panicles were positioned horizontally inside flask, so that each grain was partially submerged to nutrient medium.

• 한국자원식물학회지
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• 제30권6호
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• pp.612-617
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• 2017

The preservation of pear germplasm, like that of other clonal germplasms, is difficult because it requires conservation of whole plants or their tissues. Among the currently available methods for long-term conservation of clonal germplasm, cryopreservation of shoot tips is the most reliable and cost- and space-effective option. Alginate-coated axillary shoot tips from in vitro-grown pear were conserved successfully in liquid nitrogen (LN) following dehydration. Shoot recovery from cryopreserved shoot tips was improved greatly after 8 weeks of cold acclimation, but recovery decreased slightly after then. The highest regeneration rate was observed when in vitro shoot tips were preincubated in MS (Murashige and Skoog) medium with 0.3 M sucrose for 48 h, and when alginate-coated shoot tips were precultured in MS medium with increasing sucrose concentrations (0.5 M and 0.7 M) for 8 and 16 h, respectively. When the encapsulated beads were dehydrated for up to 7 h [25% water content (fresh weight basis)] under laminar flow, the highest regeneration rate was observed in "BaeYun No. 3" (55.7%) and "Whanggeum" (43.3%) after warming from LN. This technique is useful as a practical procedure to cryopreserve plant material that is sensitive to freezing of the surrounding cryoprotectant medium. Therefore, this technique appears to be promising for the cryopreservation of shoot tips from in vitro-grown plantlets of pear germplasm.

• Asian-Australasian Journal of Animal Sciences
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• 제9권4호
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• pp.375-379
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• 1996

The experiment investigated the possibility of using effluent from RUSITEC (rumen simulation technique) inoculated with rumen liquor or cow faeces as sources of micro-organisms for in vitro digestion of forages. Nine forages ${\times}3$ sources of inoculum were used in a factorial arrangement of treatments. Rumen liquor was collected from fistulated sheep and faeces was collected from cows. The RUSITEC apparatus consisted of 4 vessels, 2 vessels were charged with faecal liquor and 2 with rumen liquor. On the 8th day of the experiment RUSITEC effluent were collected to use in in vitro studies. In vitro OMD (g/kg) values using three sources of inoculum (fresh rumen liquor, RUSITEC effluent from rumen liquor or cow faeces) were statistically significant (p < 0.001). The regression relationships between OMD using fresh rumen liquor and RUSITEC effluent were highly significant ($R^2>0.90$). The results suggest that RUSITEC effluent either from rumen liquor or cow faeces can be used as a source of micro-organisms for in vitro digestion of forages.

• Asian-Australasian Journal of Animal Sciences
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• 제20권7호
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• pp.1049-1056
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• 2007

This study was conducted to compare the methane ($CH_4$) production estimated by in vivo (sulfur hexafluoride tracer technique ($SF_6$)) with that of two in vitro rumen simulation (RUSITEC) and gas production (IVGPT)) techniques. Four adult dry Holstein cows, aged $7.4{\pm}3.0$ years and weighing $697{\pm}70$ kg, were used for measuring methane production from five diets by the $SF_6$ technique. The experimental diets were alfalfa hay ($D_1$), corn silage + soybean meal (SBM) (910: 90, $D_2$), Italian rye grass hay +SBM (920: 80, $D_3$), rice straw +SBM (910: 90, $D_4$) and Sudan grass hay +SBM (920: 80, $D_5$). Each diet was individually fed to all 4 cows and 5 feeding studies of 17 d each were conducted to measure the methane production. In the RUSITEC, methane production was measured from triplicate vessels for each diet .In vitro gas production was measured for each of the diets in triplicate syringes. The gas produced after 24 and 48 h was recorded and gas samples were collected in vacuum vials and the methane production was calculated after correction for standard temperature and pressure (STP). Compared to the $SF_6$ technique, estimates of methane production using the RUSITEC were lower for all diets. Methane production estimated from 24 h in vitro gas production was higher (p<0.001) on $D_1$ as compared to that measured by $SF_6$, whereas on $D_2$ to $D_5$ it was lower. Compared to $SF_6$, methane production estimated from 48 h in vitro gas production was higher on all diets. However, methane estimated from the mean of the two measurement intervals (24+48 h/2) in IVGPT was very close to that of $SF_6$ (correlation 0.98), except on $D_1$. The results of our study confirmed that IVGPT is reflective of in vivo conditions, so that it could be used to generate a database on methane production potential of various ruminant diets and to examine strategies to modify methane emissions by ruminants.

• 한국식물병리학회지
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• 제13권2호
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• pp.105-112
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• 1997

Didymella bryoniae, gummy stem blight fungus of cucurbits, has been known not to produce its pycnidium in vitro without irradiation. Various methods for producing pycnidiospores of the fungus as an inoculum have been used. However, those methods have not been verified in terms of efficiency of the productivity, activity and synchronous maturation of the inoculum. Therefore, a pycnidiospore production method in vitro that is highly reliable and reproducible has to be developed to obtain a large amount of inoculum for screening disease resistant varieties or effective fungicides. Here we standardized a mass-production technique for pycnidiospores of D. bryoniae in vitro by comprehensively finding the optimal conditions such as kinds and thickness of cultural medium, growing temperature, and quality and duration of irradiation as well as examining the activity and pathogenicity of the pycnidiospores reproduced. In brief, mycelial colony on the PDA plate was cultured at 26$^{\circ}C$ for 2 days under the darkness, and then the plate was irradiated under the UV light (12 hr/a day) for 2~3 days at the same temperature(26$^{\circ}C$). Two days after UV irradiation, a great number of pycnidia was simultaneously formed. This plate was subjected to darkness again for 4~5 days to mature pycnidiospores. We could obtain a large amount of inoculum that is synchronously matured in a short period of time through the above procedures.

• 대한화장품학회지
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• 제21권1호
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• pp.1-18
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• 1995

Amino propane sulfonic acid가 피부에 미치는 영향을 non-invasive technique으로 사람의 피부를 이용하여 비교 분석하여 보았다. 측정변수로는 보습, 탄력, 피부색, 피부주름 등 4가지 측면에서 실험을 수행하였다. In vitro culture에서는 fibroblast의 증식은 촉진하였으나 keratinocyte의 중식에는 영향을 주지 못하였다. 또한 raft culture법을 이용해 APSA를 처리하였을 때도 keratinocyte에서 유사한 결과를 얻을 수 있었으므로 in vitro 상에서 표피보다는 진피 부분에서 영향을 주는 것으로 보인다. 임상시험 결과, 피부 보습에는 영향을 주지 않았으며 피부색, 탄력, 잔주름 등이 개선된 효과를 얻을 수 있었다. 특히 New Opticoprofilometry 법인 Visiometer법을 이용하였을 때 피부 주름 변화에 대해 더 유의한 결과를 얻을 수 있었다.

• 농업생명과학연구
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• 제53권2호
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• pp.15-26
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• 2019

In vivo 측정법은 비용이 많이 들고 연구기간이 길며 동물복지 측면에서 여러 문제점이 있다. 이에 대한 대안으로 지난 수십년간 in vitro 소화율 측정법이 개발되어 왔다. 본 총설에서는 대표적인 단위 동물로써 사양되고 있는 돼지의 소화기관 특징 및 소화작용에 대한 논하였다. 또한, 최근에 개발된 daisy II incubator 를 이용한 in vitro 방법을 통해 돼지에서 주요 곡류사료로 이용되고 있는 옥수수, 쌀, 소맥 및 대맥의 회장 및 전분 건물소화율을 측정하였다.