• 생명과학회지
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• 제24권1호
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• pp.86-91
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• 2014

Trichoplusia ni (T. ni) 세포는 사람 당 수송체를 이성질적으로 많은 양 생산하려 할 때 유용하게 사용되는, baculovirus 발현 시스템의 숙주세포로서 이용된다. 그러나 T. ni 세포에 존재하는 내재된 당 수송체의 높은 활동은, 발현된 외재적 당 수송체의 수송활성과 같은 직접적 증거 제시에 장애가 된다. 뿐만 아니라 곤충세포에 내재하는 당 수송체계의 특성에 대해서는 밝혀진 바가 거의 없다. 그래서 본 연구에서는 baculovirus 발현 시스템을 보다 잘 활용하기 위해 T. ni 세포의 2dGlc기질 수송에 D-fructose가 미치는 영향을 살펴 보았으며, T. ni 세포에 발현된 사람 당 수송체의 생물학적 활성을 보다 용이하게 검증하기 위해 발현된 수송체를 [$^3H$] cytochalasin B를 이용하여 photolabelling 하였다. 우선 감염되지 않은 세포와 recombinant AcMPV-GTL 감염시킨 T. ni 세포의 2dGlc uptake를 300 mM D-fructose가 있을 때와 없을 때, 그리고 $20{\mu}M$ cytochalasin B가 있을 때와 없을 때의 상황에서 살펴보았다. 감염되지 않은 세포에서의 육탄당 uptake는 D-fructose에 의해 강력하게 억제 되었으나 cytochalasin B에 의해서는 단지 미미한 억제 효과만을 보여주었다. 흥미롭게도 AcMPV-GTL 바이러스 감염된 T. ni 세포에서는 비록 2dGlc uptake율은 감염되지 않은 세포와 비교해 다소 낮았지만 육탄당 수송 억제 반응은 근본적으로 동일함을 보여 주었다. 또한 [$^3H$] cytochalasin B를 이용한 발현단백질 photolabelling에서는, L-glucose가 존재하는 상황 하에만 하나의 날카롭게 표지된 peak가, 바이러스 감염된 세포에서 관찰되었다. 감염되지 않은 세포에서는 이러한 peak는 관찰되지 않았다. 게다가 D-glucose 존재 하에서는 발현된 단백질의 photolabelling이 완전히 억제되어짐을 보여주어, labelling의 입체선택성(stereoselectivity)을 입증하였다.

• 한국수정란이식학회지
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• 제5권1호
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• pp.1-20
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• 1990

Follicular atresia is a universal and characteristic phenomenon of both non-mammalian and mammalian vertebrates. Generally it is estimated that greater than 99% of follicles become atretic in higher domestic animals and human. The number of selected follicles developing to the preovulatory stage are thus fewer. Follicles can become atretic at any stage of development. The previous studies emphasized on descriptive and retrospect aspects of a limited population of the fully grown preovulatory follicle. The main efforts in ovarian physilogical researches are focused on follicular development culminating in ovulation but recent advances have resulted in a better understanding of atresia. Nowadays, recent studies are concentrated on the induction of atresia in a selected population of follicles and of the associated cellular, endocrine, biochemical and molecular changes. The factors initiating atresia and follicle selections are worthy of investigations. Another intriguing question is whether one can predict when a follicle will become atretic, i.e., what biochemical markers indicate that a follicle is destined for atresia. It is generally agreed that atretic process may vary even in antral follicles at different stages of their differentiations and among species. The dicisive factors are follicular responsiveness and the hormonal milieu. Some generalizations can be made on the basis of experimental induction of atresia. Alteration of the pattern of follicular steroid production is associated with the initiation stage of atretic process. Atresia appears to be a process unfolding gradually and affecting progressively in increasing number of functions and components of the follicle. The oocyte may be the latest to be afflicted in the atretic process. The high steroidogenic activity of atretic follicles lends support to the notion that atresia is not necessarily a degenerative process and that atretic follicles may play an essential role in ovarian physiology. The simultaneous occurence of growth and atretic processes may render the search for regulatory mechanisms involved in atresia difficult extremely. The questions such as how follicles are selected to undergo ovulation rather than atresia or what the mechanism of atresia is remain unanswered. However, the factors regulating or modifying ovarian hormonal milieu for the initiation of follicular growth and maturation or of atresia are being elucidated.

• 한국축산식품학회지
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• 제33권5호
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• pp.595-602
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• 2013

As a major inhibitory neurotransmitter of the central nervous system in animals, ${\gamma}$-aminobutyric acid (GABA) has several physiological functions, such as anti-hypertensive, diuretic, tranquilizer and anti-stress effects in human. In order to determine strains with high GABA producing ability and glutamate decarboxylase (GAD) activity, 273 bacteria were isolated from various types of Kimchi. Strain K255 contained $386.37{\mu}g/mL$ of GABA in MRS broth containing 1% MSG, $600.63{\mu}g/mL$ of GABA in MRS broth containing 2% MSG and $821.24{\mu}g/mL$ of GABA in MRS broth containing 3% MSG. It showed that K255 had the highest GABA production ability compared to other commercial lactic acid bacteria. K255 was identified as Lactobacillus plantarum based on its API carbohydrate fermentation pattern and 16S rDNA sequence. K255 was investigated for its physiological characteristics. The optimum growth temperature of K255 was $37^{\circ}C$and cultures took 13 h to reach the pH 4.4. K255 showed more sensitive to bacitracin in a comparison of fifteen different antibiotics, and showed most resistance to kanamycin and vancomycin. Moreover, it was comparatively tolerant to bile juice and acid and displayed resistance to Escherichia coli, Salmonella Typhimurium, Staphylococcus aureus, with rates of 30.8%, 29.7%, and 23.4% respectively. These results demonstrate that K255 could be an excellent strain for the production of functional products.

• BMB Reports
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• 제53권9호
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• pp.484-489
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• 2020

Epilepsy is a neurological disorder characterized by unpredictable seizures, which are bursts of electrical activity that temporarily affect the brain. Cereblon (CRBN), a DCAFs (DDB1 and CUL4-associated factors), is a well-established protein associated with human mental retardation. Being a substrate receptor of the cullin-RING E3 ubiquitin ligase (CRL) 4 complex, CRBN mediates ubiquitination of several substrates and conducts multiple biological processes. In the central nervous system, the large-conductance Ca²⁺-activated K⁺ (BK_Ca) channel, which is the substrate of CRBN, is an important regulator of epilepsy. Despite the functional role and importance of CRBN in the brain, direct injection of pentylenetetrazole (PTZ) to induce seizures in CRBN knock-out mice has not been challenged. In this study, we investigated the effect of PTZ in CRBN knock-out mice. Here, we demonstrate that, compared with WT mice, CRBN knock-out mice do not show the intensification of seizures by PTZ induction. Moreover, electroencephalography recordings were also performed in the brains of both WT and CRBN knockout mice to identify the absence of significant differences in the pattern of seizure activities. Consistently, immunoblot analysis for validating the protein level of the CRL4 complex containing CRBN (CRL4^Crbn) in the mouse brain was carried out. Taken together, we found that the deficiency of CRBN does not affect PTZ-induced seizure.

• 지적과 국토정보
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• 제47권1호
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• pp.27-35
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• 2017

농경지, 공업지역 개발, 주거지 확장과 같은 인간의 활동은 갯벌생태계에 중요한 위협이 되어 왔고, 연안갯벌 감소의 가장 중요한 원인이었다. 가로림만은 가장 중요한 습지 서식처 중에 하나이며, 해양수산부는 가로림만을 2016년 7월 해양생태계보호구역으로 지정하였다. 본 연구의 목적은 Landsat 5 (TM), Landsat 7 (ETM+), Landsat 8 (OLI & TIRS)의 위성영상을 통해 가로림만의 공간적인 패턴을 분석하는 것이다. 가로림만의 표층온도와 NDVI는 공간분석기법에 의해 처리하였고, 시계열분석이 25년 동안의 Landsat 영상을 통해 적용되었다. 시계열 온도/식생 분포지도는 위성영상에 의해 몇 개의 갯벌 습지 서식처로 비교되었다. Landsat영상은 1988년부터 2014년까지 습지식생의 변화를 보여주었고, 가로림만 남부지역은 갯벌이 분포된 지역에 연안 습지에서 식생의 공간분포 변화되었음을 보여주고 있다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권21호
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• pp.9211-9216
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• 2014

CXCR7 is involved in tumor development and metastasis in multiple malignancies. However, the function and molecular mechanisms of action of CXCR7 in human cervical cancer are still unclear. In the present study a loss of-function approach was used to observe the effects of recombinant CXCR7 specific small interfering RNA pBSilence1.1 plasmids on biological behavior including proliferative activity and invasive potential, as indicated by MTT assays with the cervical cancer SiHa cell line in vitro. Reverse transcription polymerase chain reaction and Western blotting revealed that CXCR7 was downregulated in transfected compared with control cells, associated with inhibited cell growth, invasiveness and migration. The expression of CXCR7 and CXCL12 was also determined immunohistochemically in 152 paraffin-embedded, cervical squamous cell carcinoma (CSCC) and cervical intraepithelial neoplasia (CIN), or normal cervical epithelial to assess clinico-pathological pattern and CXCR7 status with respect to cell differentiation and lymph node metastasis in Uighur patients with CSCC. CXCR7 and CXCL12 expression was higher in cervical cancer than CIN and normal cervical mucosa, especially in those with higher stage and lymph node metastasis. CXCL12 appeared to be positively regulated by CXCR7 at the post-transcriptional level in CSCC. We propose that aberrant expression of CXCR7 plays a role in carcinogenesis, differentiation and metastasis of CSCC, implying its use as a potential target for clinical biomarkers in differentiation and lymph node metastasis.

• BMB Reports
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• 제38권5호
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• pp.624-631
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• 2005

Tuberculosis, caused by Mycobacterium tuberculosis, continues to be one of the main diseases to mankind. It is urgent to discover novel drug targets for appropriate antimicrobial agents against this human pathogen. The shikimate pathway is onsidered as an attractive target for the discovery of novel antibiotics for its essentiality in bacteria and absence in mammalian cells. The Mycobacterium tuberculosis aroE-encoded shikimate dehydrogenase was cloned, expressed and purified. Sequence alignment analysis shows that shikimate dehydrogenase of Mycobacterium tuberculosis exhibit the pattern of G-X-(N/S)-V-(T/S)-X-PX-K, which is highly conserved within the shikimate dehydrogenase family. The recombinant shikimate dehydrogenase spectrum determined by CD spectroscopy showed that the percentages for $\alpha$-helix, $\beta$-sheet, $\beta$-turn, and random coil were 29.2%, 9.3%, 32.7%, and 28.8%, respectively. The enzymatic characterization demonstrates that it appears to be fully active at pH from 9.0 to 12, and temperature $63^{\circ}C$. The apparent Michaelis constant for shikimic acid and $NADP^+$ were calculated to be about $29.5\;{\mu}M$ and $63\;{\mu}M$. The recombinant shikimate dehydrogenase catalyzes the substrate in the presence of $NADP^+$ with an enzyme turnover number of $399\;s^{-1}$. Zymological studies suggest that the cloned shikimate dehydrogenase from M. tuberculosis has a pretty activity, and the work should help in the discovery of enzyme inhibitors and further of possible antimicrobial agents against Mycobacterium tuberculosis.

• 한국정밀공학회지
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• 제30권3호
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• pp.331-339
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• 2013

The Interest in disease prevention and rehabilitation is increasing depending on increase of patients with spinal. This is being developed using the spine stabilization device is being studied. So far studies have only evaluated the effect on trunk stabilization exercises but analysis of human movement patterns for active movement and passive movement did not. We assessed the muscle activity of trunk and leg muscle during passive and active tilt mode on eight tilt directions at tilt angle of $30^{\circ}$ using 3-D dynamic postural balance training system. We performed experimental study on the muscular activities of trunk muscle about rectus abdominis, external obliques, latissimus dorsi, erector spinae, and leg muscle about rectus femoris, Biceps femoris, Tibialis Anterior, gastrocnemius. As a result, muscle activation was different depending on the direction of movement and pattern. The results indicate that various patterns of spinal stabilization exercise system could be applied to an effective training of chronic low back pain patients.

• Molecules and Cells
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• 제40권10호
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• pp.761-772
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• 2017

Glioblastoma is the most frequent and most aggressive brain tumor in adults. Solute carrier family 8 member 2 (SLC8A2) is only expressed in normal brain, but not present in other human normal tissues or in gliomas. Therefore, we hypothesized that SLC8A2 might be a glioma tumor suppressor gene and detected the role of SLC8A2 in glioblastoma and explored the underlying molecular mechanism. The glioblastoma U87MG cells stably transfected with the lentivirus plasmid containg SLC8A2 (U87MG-SLC8A2) and negative control (U87MG-NC) were constructed. In the present study, we found that the tumorigenicity of U87MG in nude mice was totally inhibited by SLC8A2. Overexpression of SLC8A2 had no effect on cell proliferation or cell cycle, but impaired the invasion and migration of U87MG cells, most likely through inactivating the extracellular signal-related kinases (ERK)1/2 signaling pathway, inhibiting the nuclear translocation and DNA binding activity of nuclear factor kappa B ($NF-{\kappa}B$), reducing the level of matrix metalloproteinases (MMPs) and urokinase-type plasminogen activator (uPA)-its receptor (uPAR) system (ERK1/2-$NF-{\kappa}B$-MMPs/uPA-uPAR), and altering the protein levels of epithelial to mesenchymal transitions (EMT)-associated proteins E-cardherin, vimentin and Snail. In addition, SLC8A2 inhibited the angiogenesis of U87MG cells, probably through combined inhibition of endothelium-dependent and endothelium-nondependent angiogenesis (vascular mimicry pattern). Totally, SLC8A2 serves as a tumor suppressor gene and inhibits invasion, angiogenesis and growth of glioblastoma.

• 한국운동역학회지
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• 제26권1호
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• pp.135-142
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• 2016

Objective: The purpose of this study was to investigate the acute effect of walking on high heels on the behavior of fascicle length and activation of the lower limb muscles. Methods: Twelve healthy inexperienced high heel wearers (age: $23.1{\pm}2.0yr$, height: $162.4{\pm}4.9cm$, weight: $54.4{\pm}8.5kg$) participated in this study. They walked in high heels (7 cm) and barefoot on a treadmill at their preferred speed. During the gait analysis, the lower limb joint kinematics were obtained using a motion analysis system. In addition, the changes in fascicle length and the level of activation of the medial gastrocnemius (MG) were simultaneously monitored using a real-time ultrasound imaging technique and surface electromyography, respectively. Results: The results of this study show that the MG fascicle operates at a significantly shorter length in high heel walking ($37.64{\pm}8.59mm$ to $43.99{\pm}8.66mm$) in comparison with barefoot walking ($48.26{\pm}9.02mm$ to $53.99{\pm}8.54mm$) (p < .05). In addition, the MG fascicle underwent lengthening during high heel walking with relatively low muscle activation while it remained isometric during barefoot walking with relatively high muscle activation. Conclusion: Wearing high heels alters the operating range of the MG fascicle length and the pattern of muscle activation, suggesting that prolonged wearing of high heels might induce structural alterations of the MG that, in turn, hinder normal functioning of the MG muscle during walking.