Selectins are cell membrane glycoproteins that recognize specific glycoconjugates expressed on the surface of cells. Then, selectins adjust cell-cell interactions that are important in inflammation, hemostasis and cancer metastasis. Selectins mediate leukocyte calls to move into the site of inflammation through interactions with activated endothelial cells or endogenous selectin ligands expressed in high endothelial venules. Types of selectins are divided into L-selectin, E-selectin and P-selectin, which are called to CD62L, CD62E, and CD62P, respectively. Each selectin is composed of four regions; the C-type lectin region of N-terminal, the epidermal growth factor (EGF) region, the intracellular C-terminal region, and the hydrophobic transmembrane region. They have similar structures but differ in their binding specificities and tissue distributions. The selectin family commonly recognizes the sialyl Lewis X (sLeX) on carbohydrate structures. Although biological ligands bound to each selectin are different from each other, they commonly bind to P-selectin glycoprotein ligand-1 (PSGL-1) ligand. The PSGL-1 ligand is a glycoprotein promoting cell adhesion in inflammatory responses. If the absence of selectins and their ligands in humans and animals are, should lead to persistent infections and diseases. Selectin family must be considered as a key subject for drug discovery since they have various functions depending on the ligand which they bind to.
페로브스카이트 양자점에 물을 첨가하여 절대양자효율과 안정성이 향상되는 현상에 대해 연구를 수행하였다. 수분에 의해 특성이 저하되는 페로브스카이트 양자점의 일반적인 성질과 다르게 절대양자효율과 안정성이 향상되는 원인을 여러 가지 분석장비를 활용해 분석하였다. 물을 첨가했을 때 결정성이 향상되는 것을 확인하였다.
In order to understand biological phenomena accurately, single molecule techniques using a physical research approach to molecular interactions have been developed, and are now widely being used to study complex biological processes. In this review, we discuss some of the single molecule methods which are composed of two major parts: single molecule spectroscopy and manipulation. In particular, we explain how these techniques work and introduce the current research which uses them. Finally, we present the oral biology research using the single molecule methods.
본 연구에서는 전도성 고분자인 polystyrene sulfonic acid doped poly~3,4-ethylenedioxythiophene (PEDOT:PSS)을 소스/드레인 전극으로 사용한 펜타센 단분자 유기 반도체 기반의 전계효과 트랜지스터를 제작하고, 금을 소스/드레인 전극으로 하는 기준소자와 전기적 특성을 비교하여 평가하였다. 전기적 특성을 측정한 결과, PEDOT:PSS 박막은 금 박막에 비해 상대적으로 낮은 전도도를 가짐에도 불구하고 PEDOT:PSS 소스/드레인 전극을 갖는 펜타센 유기 트랜지스터는 금을 소스/드레인 전극으로 갖는 기준 소자와 비교할 만한 성능을 보였다. 이는 PEDOT:PSS와 펜타센 사이의 접촉저항이 금과 펜타센 사이의 접촉저항보다 낮아 상대적으로 낮은 전기전도도에 의한 성능 저하를 보상하기 때문으로 추측된다.
Programmed cell death (PCD) is decisive in eliminating affected cells in human cancers, whereas there are increasing cases of cancer-related death due to side effects of modern treatment methods. There is an urge for new methods of growth inhibition and elimination of cancer cells with a lower cytotoxicity to normal cells. Irregularity along PCD pathways plays a crucial role in cancer cell carcinogenesis. Apoptosis is a distinct cell death mechanism occurring in multicellular organisms and also called type one programmed cell death. Autophagy and paraptosis are non-apoptotic PCD occurring in multicellular organisms. Natural compounds are the fundament of pharmacological treatments, and flavonoids are natural polyphenolic compounds which are unique due to their diverse chemical structures and various biological active mechanisms like anticancer, anti-inflammatory, antioxidative and much more. This gives an increasing number of studies indicating that some flavonoids from medicinal plants could be promising candidates for new natural anticancer drugs, which attract high interests of academic researchers and advanced users. An understanding of the underlying mechanism of PCD induced by flavonoids in cancer cells is important as it plays a pivotal role in the pathogenesis of many diseases. This systematic review is to report flavonoids and their derivatives as new anticancer candidates to stimulate PCD with a different mechanism based on the pharmacological evidence.
Bovine viral diarrhea virus (BVDV) is a major pathogen that may be one of the main reasons for economic losses in the livestock industry. BVDV is a well-characterized member of Flaviviridae family with plus-stranded RNA viruses. Non-structural NS5B protein is RNA-dependent RNA polymerase, which is responsible for viral RNA synthesis and genome replication of BVDV. Therefore, the NS5B polymerase is a key target for the discovery of anti-BVDV drugs. A number of small-molecule inhibitors against the NS5B polymerase have been reported in literature of which we collected series molecules having various scaffold with their biological data determined by evident experimental conditions, methods and procedures. Then, we constructed database of 655 small-molecule NS5B inhibitors having definitive activity values, structural parameters, and physicochemical properties (such as molecular hydrophobicity, hydrophilicity, polarity, Hbond donors and H-bond acceptors) associated with their absorption and permeability through a cheminformatics approach. The database was opened to provide insight for allosteric NS5B inhibitors of BVDV with an accessible platform on the web (http://nabic.rda.go.kr/chemical genomic database/BVDV RNA dependent RNA polymerase inhibitors). This molecular information in the database would be useful in attempting to identify features and decision factors that enhance anti-BVDV activity or increase selectivity of the allosteric inhibitor. These anti-BVDV molecules could also be screening for the purpose of exploiting potent NS5B inhibitors in the same family (e.g., HCV, CSFV, YFV, WNV, and DENV).
본 연구에서는, F4-ZnPc 광활성층 기반의 저분자 유기태양전지의 성능을 최적화 하기 위해서 다 양한 조건의 홀이동층과 전자이동층을 조합하는 연구를 진행하였다. BF-DPB 호스트 유기물에 C60F36 또 는 NDP9 도펀트를 도핑한 조합을 홀이동층으로 사용하였고, 전자이동층으로는 W2(hpp)4가 도핑된 C60 또는 순수 C60/Bphen 물질을 사용하였다. 다양한 홀/전자이동층의 조합은 유기태양전지의 단락전류밀도와 fill factor, 효율에 영향을 끼치는 것을 관찰할 수 있었다.
Expression of epithelial cell adhesion molecule (EpCAM) in the early phase of hepatocarcinogenesis induced by diethylnitrosamine (DEN) was investigated. At 14 days of age, 60 ICR mice were divided into two groups and treated with saline (group 1) or DEN (group 2, 10 mg/kg of body weight, i.p. injection), and were sacrificed at 6 h and 1, 2, 3, 7, and 28 days after treatment with saline or DEN. During necropsy, half of the liver from saline- or DEN-treated mice was processed for histopathological examination and immunohistochemical staining of EpCAM and apoptosis. The remaining liver tissue was snap-frozen in liquid nitrogen for RNA extraction and analysis of EpCAM mRNA expression. Immunohistochemical examination showed that EpCAM expression was detected only in a small number of hepatocytes from saline-treated mice and its expression was detected in bile duct cells and round cells around portal areas, as well as hepatocytes in the livers of DEN-treated mice. In addition, multiple apoptotic cells were found in the livers of mice treated with DEN. EpCAM mRNA expression was significantly higher in DEN-treated mice at 1, 7, and 28 days compared to saline-treated mice at 6 h (P<0.01). Taken together, EpCAM expression and apoptosis were increased in liver by DEN treatment.
The shortage of human organs for transplantation has induced the research on the possibility of using animal as porcine. However, pig to human transplantation as known as xeno-transplantation has major problem as immunorejection. Recently, the solutions of pig to human xenotransplantation are commonly mentioned as having a genetically modification which include alpha 1, 3 galatosyl transferase knockout (GTKO) and immune-suppressing gene transgenic model. Unfortunately, the expression level of transgenic gene is very low activity. Therefore, development of gene overexpression system is the most urgent issue. Also, the tissue specific overexpression system is very important. Because most blood vessels are endothelial cells, establishment of the endothelial-specific promoter is attractive candidates for the introduction of suppressing immunorejection. In this study, we focus the ICAM2 promoter which has endothelial-specific regulatory region. To detect the regulatory region of ICAM2 promoter, we cloned 3.7 kb size mini-pig ICAM2 promoter. We conduct serial deletion of 5' flanking region of mini-pig ICAM2 promoter then selected promoter size as 1 kb, 1.5 kb, 2 kb, 2.5 kb, and 3 kb. To analyze promoter activity, luciferase assay system was conducted among these vectors and compare endothelial activity with epithelial cells. The reporter gene assay revealed that ICAM2 promoter has critical activity in endothelial cells (CPAE) and 1 kb size of ICAM2 promoter activity was significantly increased. Taken together, our studies suggest that mini-pig ICMA2 promoter is endothelial cell specific overexpression promoter and among above all size of promoters, 1 kb size promoter is optimal candidate to overcome the vascular immunorejection in pig to human xenotransplantation.
The bio-organic thin film transistor (BiOTFT) with the DNA and DNA-surfactant complex as a
dielectric layer shows memory function. In order to investigate the effect of surfactant structure on the OTFT memory device performance, different kinds of surfactant were introduced. The octadecyltrimethylammonium chloride (OTMA), ctyltrimethylammonium chloride (CTMA), or lauroylcholine chloride (Lau) as cationic surfactant as mixed with DNA to prepare the DNA complex through the electrostatic interaction. In addition, the different molecular weight DNA also has been studied to analyze the effect of DNA chain length on the performance of the physical property. Many kinds of methods including UV-vis, Circular dichiroism (CD), I-V characteristic and atomic force microscope (AFM) have been applied to analyze the property of DNA complex. In conclusion, all of DNA complex with CTMA, OTMA and Lau revealed to work as the bio-organic thin film transistor memory, and the device fabricated by Lau has the highest ON current and showed better device performance.