• 한국자원식물학회지
• /
• 제33권6호
• /
• pp.615-623
• /
• 2020

Brassica rapa is one of the most valuable vegetable crops worldwide. Cultivated varieties of B. rapa exhibit diverse developmental and morphological appearances, which includes important vegetables, oilseeds, and fodder crops. In this study, various phenotypes of recombinant inbred lines (RILs) of B. rapa were investigated, including their responses to five different pathogenic Botrytis cinerea isolates, responses to aphid and thrips during flowering stages, days to flowering, and plant heights. Responses of 113 RILs to five different B. cinerea isolates showed variations, suggesting that genetic factors controlling resistance or tolerance against each isolate were dependent on isolate/genotype pairs. Correlation analysis was performed to understand the nature of genetic factors and the relationship among these phenotypes. Although high levels of correlation were not detected between phenotypes assessed in this study, statistically significant correlation was detected for several combinations. Significant positive correlations were found for different B. cinerea isolates, supporting that certain levels of commonality could exist in genetic components controlling resistance against different B. cinerea isolates. Based on correlation analysis using numbers of insects counted on plants, it was speculated that genetic factors responsible for aphid tolerance or repellence might be also involved in the response against thrips. Relationship between vegetative growth and tolerance against B. cinereal or insects is rather more complicated. However, it was observed that shorter plants appeared to have a certain level of tolerance or repellence against both aphids and thrips. Data presented in this study could be used to assist further genetic studies and breeding efforts to obtain Botritis and insect resistance for B. rapa.

• 대한치과보철학회지
• /
• 제42권3호
• /
• pp.307-326
• /
• 2004

Statement of problem. The long-term success of implants is the development of a stable direct connection between bone and implant surface, which must be structural and functional. To improve a direct implant fixation to the bone, various strategies have been developed focusing on the surface of materials. Among them, altering the surface properties can modify cellular responses such as cell adhesion, cell motility and bone deposition. Purpose. This study was to evaluate the cellular behaviors on the surface-modified titanium by morphological observation, cellular proliferation and differentiation. Material and methods. Specimens were divided into five groups, depending on their surface treatment: electropolishing(EP) anoclizing(AN), machining(MA), blasting with hydroxyapatite particle(RBM) and electrical discharge machining(EDM). Physicochemical properties and microstructures of the specimens were examined and the responses of osteoblast-like cells were investigated. The microtopography of specimens was observed by scanning electron microscopy(SEM). Surface roughness was measured by a three-dimensional roughness measuring system. The microstructure was analyzed by X-ray diffractometer(XRD) and scanning auger electron microscopy(AES). To evaluate cellular responses to modified titanium surfaces, osteoblasts isolated from neonatal rat were cultured. The cellular morphology and total protein amounts of osteoblast-like cell were taken as the marker for cellular proliferation, while the expression of alkaline phosphatase was used as the early differentiation marker for osteoblast. In addition, the type I collagen production was determined to be a reliable indicator of bone matrix synthesis. Results. 1. Each prepared specimen showed specific microtopography at SEM examination. The RBM group had a rough and irregular pattern with reticulated appearance. The EDM-treated surface had evident cracks and was heterogeneous consisting of broad sheet or plate with smooth edges and clusters of small grains, deep pores or craters. 2. Surface roughness values were, from the lowest to the highest, electropolished group, anodized group, machined group, RBM group and EDM group. 3. All groups showed amorphous structures. Especially anodized group was found to have increased surface oxide thickness and EDM group had titaniumcarbide(TiC) structure. 4. Cells on electropolished, anodized and machined surfaces developed flattened cell shape and cells on RBM appeared spherical and EDM showed both. After 14 days, the cells cultured from all groups were formed to be confluent and exhibited multilayer proliferation, often overlapped or stratified. 5. Total protein amounts were formed to be quite similar among all the group at 48 hours. At 14 days, the electropolished group and the anodized group induced more total protein amount than the RBM group(P<.05). 6. There was no significant difference among five groups for alkaline phosphatase(ALP) activity at 48 hours. The AN group showed significantly higher ALP activity than any other groups at 14 days(P<.05). 7. All the groups showed similar collagen synthesis except the EDM group. The amount of collagen on the electropolished and anodized surfaces were higher than that on the EDM surface(P<.05).

• The Korean Journal of Physiology and Pharmacology
• /
• 제8권6호
• /
• pp.351-354
• /
• 2004

The cytotoxicological responses to insect growth regulator (IGR), using tebufenozide as ecdysteroid mimic, were investigated in Drosophila Kc cells. Treatment of Kc cells with tebufenozide showed significant growth inhibition and striking morphological changes including aggregation and elongation of the cells. In order to understand the cellular mechanism underlying the response of Drosophila cells to tebufenozide, immunofluorescence microscopy was performed. We found that treatment of Kc cells with tebufenozide enhanced the reorganization of f-actin and stimulated the expression of hsp27. These data suggest a possible association of filamentous actin (f-actin) and hsp27 in the cytotoxicological mechanisms of growth regulators in Drosophila cells.

• 영어어문교육
• /
• 제17권1호
• /
• pp.81-99
• /
• 2011

The role of corrective feedback (CF) has long been discussed in the field of second language acquisition. It has been claimed that CF enables learners to notice the problems in their second language (L2) production. However, it should not be assumed that learners always adequately interpret teachers' responses to their problematic utterance as correction. Especially when feedback is provided in an implicit way, the possibility that CF goes unnoticed should not be excluded. In this regard, the study aims to investigate how learners perceive teachers' corrective feedback in English classrooms in Korea. The study focuses particularly on examining the relationship between type of feedback and target linguistic content with learner interpretation of teacher corrective intention. Nine classrooms were observed and videotaped. Forty-five students and nine teachers participated in stimulated recall interviews. Their comments were analyzed to document the learners' perception and the teachers' intention of feedback. It was found that learner perception of teacher corrective intention was at its greatest when feedback was provided explicitly and was focused on morphological errors.

• 대한핵의학회지
• /
• 제36권1호
• /
• pp.64-73
• /
• 2002

FDG-PET has potential as an effective, non-invasive tool to measure tumor response to anticancer therapy. The changes in tumor FDG uptake may provide an early, sensitive guide to the clinical and subclinical response of tumors to cancer treatment, as well as functional assessment of residual viable tumor. This may allow the evaluation of subclinical response to anticancer drugs in early clinical trials and improvements in patients management. However, monitoring tumor responses with FDG-PET is still in its infancy. The methods of measurement of FDG uptake are currently diverse and timing with respect to anti cancer therapy variable. Therefore, there is a need for larger-scale trials along with standardized methodology and a collection of reproducibility data. The recent guideline from the European group seems to be the most comprehensive. In future, the combination of morphological and metabolic images may improve the quantitative nature of these measurements by relating tumor viability to total tumor mass. More data on sensitivity and specificity of FDG-PET technique are needed along with continued advancement of PET methodology.

• Molecules and Cells
• /
• 제23권2호
• /
• pp.154-160
• /
• 2007

An Arabidopsis hy4 mutant that is specifically impaired in its ability to undergo blue light dependent photomorphogenesis was used to identify cryptochrome 1 signaling-related components. Proteomic analysis revealed about 205 differentially expressed protein spots in the blue light-irradiated hy4 mutant compared to the wild-type. The proteins corresponding to 28 up-regulated and 33 down-regulated spots were identified. Obvious morphological changes in the hy4 mutant were closely related to the expression of various transcription factors. Our findings suggest that blue light signals may be involved in many cellular processes including disease resistance and stress responses.

• Environmental Analysis Health and Toxicology
• /
• 제23권4호
• /
• pp.277-284
• /
• 2008

The ecotoxicological effects of 4-tert-octylphenol were observed on non-biting midge, Chironomus plumosus collected from Anyang stream in Seoul. The survival rate and adult emergence rate on C. plumosus exposed to octylphenol were not significantly affected. However, 4-tert-octylphenol induced developmental delay and disrupted sex ratio in high concentration of octylphenol. The mouth deformity such as tooth deletion or fusion in mentum, and tooth deletion in mandible were observed exposure to 4-tert-octylphenol. The deformity type of the mentum showed deletion (LT, 6.7%), and fusion (LT, 6.3%). Moreover, tooth deletion of mandible was observed in 4-tert-octylphenol treated groups (6.7%, 3 ppm).

• Asian Pacific Journal of Cancer Prevention
• /
• 제17권3호
• /
• pp.1057-1060
• /
• 2016

Background: The tumor suppressor p53 is as a regulator of cell proliferation, apoptosis and many other biological processes as well as external and internal stress responses. Mdm2 SNIP309 is a negative regulator of 53. Therefore, this study aimed to determine the role of the Mdm2 SNIP 309 polymorphism in the gastric mucosal morphological patterns in patients with Helicobacter pylori associated gastritis. Materials and Methods: A prospective cross-sectional study was carried out from November 2014 through November 2015. Biopsy specimens were obtained from patients and infection was proven by positive histology. Gastric mucosa specimens were sent to the Molecular Genetics Unit, Institute of Medicine, Suranaree University of Technology where they were tested by molecular methods to detect the patterns of Mdm2 SNIP 309 polymorphism using the real-time PCR hybridization probe method. The results were analyzed and correlated with gastric mucosal morphological patterns by using C-NBI endoscopy. Results: A total of 300 infected patients were enrolled and gastric mucosa specimens were collected. In this study the percentage of Mdm2 SNIP 309 T/T homozygous and Mdm2 SNIP309 G/T heterozygous was 78% and 19 % respectively whereas Mdm2 SNIP309 G/G homozygous was 3%. Mdm2 SNIP 309 T/T homozygous and Mdm2 SNIP309 G/T heterozygosity correlated with type 1 to type 3 gastric mucosal morphological patterns (P<0.01) whereas Mdm2 SNIP309 G/G homozygous correlated with type 4 and type 5 (P<0.01). Conclusions: Our study finds the frequency of Mdm2 SNIP309 G/G in a Thai population is very low, and suggests that this can explain ae Thailand enigma. Types 1 to type 3 are the most common gastric mucosal morphological patterns according to the unique genetic polymorphism of MDM2 SNIP 309 in the Thai population.

• 생태와환경
• /
• 제52권1호
• /
• pp.13-20
• /
• 2019

인간의 산업활동 증가로 인해 발생하는 크롬과 구리 중금속은 강우와 폐수를 통해 환경으로 유입되어 서식 생물에 유해한 영향을 준다. 본 연구에서는 하천 수생태계 오염 지표 생물인 Chironomus plumosus를 대상으로 크롬과 구리 노출에 따른 생존율, 성장률, 우화율, 성비 등의 생물학적 반응과 하순기절 기형의 형태적 영향을 관찰하였다. C. plumosus의 생존율은 크롬과 구리 노출 시간-농도의존적인 감소를 나타냈다. 성장률은 크롬 노출 후 4일째 감소하였고 구리 노출 시에는 상대적으로 고농도인 $1000mg\;L^{-1}$에서 모든 노출 시간에 감소함을 확인하였다. 또한 $1000mg\;L^{-1}$ 구리 노출에서 대조군에 비해 우화율이 급격히 감소함을 관찰하였다. 크롬 노출 시 성비는 상대적 저농도에서(10과 $50mg\;L^{-1}$) 대조군과 달리 암컷의 비율이 증가했지만 구리 노출 시에는 상대적으로 고농도인 $1000mg\;L^{-1}$에서 수컷의 비율이 눈에 띄게 증가하는 성비불균형을 확인하였다. 나아가 C. plumosus 하순기절 형태적 기형은 크롬과 구리 노출에 따라 노출군에서 발생함을 관찰하였다. 이러한 결과는 크롬과 구리의 수생태계 유입이 서식하는 저서무척추동물인 C. plumosus의 생물학적, 형태적 유해 스트레스를 제공하며 C. plumosus가 크롬과 구리 같은 중금속 독성평가에 민감하게 반응하는 지표종임을 제시한다.

• 한국미생물·생명공학회지
• /
• 제31권1호
• /
• pp.75-82
• /
• 2003

환경 오염원으로서 폭약 hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX)에 대한 RDX 분해세균 Pseudomonas sp. HK-6의 세포반응과 형태변화에 대하여 조사하였다. 아치사조건의 RDX농도와 노출시간에 따른 균주 HK-6의 생존율을 분석한 결과, 이 세균의 생존율은 스트레스 충격 단백질의 생성과 비례하였다. 총세포 지방산 조성분석에서 균주 HK-6는 trypticase soy agar(TSA)에서 자랄 때 보다 RDX배지에서 자랄 때 여러 가지 종류의 지방산이 생성되거나 사라지는 것이 밝혀졌다. Anti-DnaK와 anti-GroEL을 이용하여 SDS-PAGE와 Western blot을 통한 분석으로 균주 HK-6는 70 kDa DanK와 60 kDa GroEL을 포함하는 몇가지 스트레스 충격단백질을 생성하는 것으로 밝혀졌다. RDX에 노출된 HK-6배양에서 수용성 단백질 분획에 대하여 2-D PAGE를 실시하였으며, pH 3에서 pH 10 범위에서 약 300 spots가 silver로 염색된 gel상에서 관찰되었다. 그 결과, RDX에 대한 반응으로 10여개의 spots가 현저히 유도 발현되었다. RDX(0.135mM, 12시간)에 노출된 세포는 구멍이 나타나고 표면의 불규칙적인 형태 변화가 일어나 죽게되는 것이 주사 전자현미경을 통하여 관찰되었다.