• International Journal of Stem Cells
• /
• 제17권1호
• /
• pp.15-29
• /
• 2024

The development and differentiation of endothelial cells (ECs) are fundamental processes with significant implications for both health and disease. ECs, which are found in all organs and blood vessels, play a crucial role in facilitating nutrient and waste exchange and maintaining proper vessel function. Understanding the intricate signaling pathways involved in EC development holds great promise for enhancing vascularization, tissue engineering, and vascular regeneration. Hematopoietic stem cells originating from hemogenic ECs, give rise to diverse immune cell populations, and the interaction between ECs and immune cells is vital for maintaining vascular integrity and regulating immune responses. Dysregulation of vascular development pathways can lead to various diseases, including cancer, where tumor-specific ECs promote tumor growth through angiogenesis. Recent advancements in single-cell genomics and in vivo genetic labeling have shed light on EC development, plasticity, and heterogeneity, uncovering tissue-specific gene expression and crucial signaling pathways. This review explores the potential of ECs in various applications, presenting novel opportunities for advancing vascular medicine and treatment strategies.

• Parasites, Hosts and Diseases
• /
• 제28권1호
• /
• pp.11-24
• /
• 1990

간흡충의 항원성 부위를 규명하기 위하여 간흡충 충체로부터 분리한 체액을 실험 토끼에 주사하여 면역시킨 IgG와 간흡충에 감염된 실험 토끼의 IgG를 간흡충 조직 항원에 반응시키고 면역황금 표식법을 이용하여 전자현미경으로 관찰한 바 그 결과는 다음과 같다. 간흡충의 조직세포 사이의 구성물인 세포간질과 맹관의 내용물, 그리고 맹관 막 구조물은 충체에 감염된 IgG와 체액 항원에 면역된 IgG 모두에서 항원-항체 반응이 관찰되었지만 체액 항원으로 면역된 IgG에서 다소 강한 반응이 나타났다. 표피의 기저층과 난황선의 난황 물질은 충체에 감염된 IgG에서는 반응이 나타나지 않았으나 체액 항원에 면역된 IgG에서는 강한 반응이 나타나 이들을 구 성하는 물질은 체액 반응 IgG에 대한 특이 항원으로 생각되었다. 배설관의 내용물과 막 구조물은 충체에 감염된 IgG에 대한 반응이 특이하였으나 체액 항원에 면역된 IgG에 대한 반응은 매우 미 약 하여 항원성에 차이점이 있는 것으로 생각되었다. 수정낭의 정자세포 간질은 충체 감염 IgG에 반응 하고 정자세포의 두부는 체액 항원으로 면역된 IgG에 반응하여 매우 상이한 항원성이 나타났다. 이상의 결과로 보아 충체의 세포간질과 맹관 구성물은 충체 감염시와 체액 항원에 면역된 IgG에 대하여 반응의 정도 차이는 있으나 항원성으로 관찰되는 것은 동일하였다. 그러나 수정낭의 세포간질과 배설낭의 구성물질은 충체에 감염된 IgG에 대한 특이 항원이며 수정낭 내의 정자들의 두부와 난황을 구성하는 물질은 체액 면역 IgG에 대한 특이 항원인 것으로 생각된다.

• 한국발생생물학회지:발생과생식
• /
• 제23권4호
• /
• pp.367-375
• /
• 2019

Pufferfish (Takifugu spp.) are economically important edible marine fish. Mistakes in pufferfish classification can lead to poisoning; therefore, accurate species identification is critical. In this study, we used the mtDNA cytochrome c oxidase subunit I gene (COI) to design specific primers for six Takifugu species among the 21 domestic or imported pufferfish species legally sold for consumption in Korea. We rapidly and simultaneously identified these pufferfish species using a highly efficient, multiplex polymerase chain reaction (PCR) system with the six species-specific primers. The results showed that species-specific multiplex PCR (multiplex species-specific polymerase chain reaction; MSS-PCR) either specifically amplified PCR products of a unique size or failed. MSS-PCR yielded amplification fragment lengths of 897 bp for Takifugu pardalis, 822 bp for T. porphyreus, 667 bp for T. niphobles, 454 bp for T. poecilonotus, 366 bp for T. rubripes, and 230 bp for T. xanthpterus using the species-specific primers and a control primer (ca. 1,200 bp). We visualized the results using agarose gel electrophoresis to obtain accurate contrasts of the six Takifugu species. MSS-PCR analysis is easily performed and provides identification results within 6 h. This technique is a powerful tool for the discrimination of Takifugu species and will help prevent falsified labeling, protect consumer rights, and reduce the risk of pufferfish poisoning..

• Journal of Microbiology and Biotechnology
• /
• 제14권3호
• /
• pp.450-455
• /
• 2004

A reducing glucose-carrying polymer, called poly [3-O-(4'-vinylbenzyl)-D-glucose］(PVG), was interacted with HepG2 cells including a type-l glucose transporter (GLUT-1) on the cell membrane. The cooperative interaction between a number of GLUT-1s and a number of reducing 3-O-methyl-D-glucose moieties on the PVG polymer chain was found to be responsible for the increase in the interaction with HepG2 cells. The affinity between the cells and the PVG was studied using RITC-labeled glycopolymers. The specific interaction between the GLUT-1 on HepG2 cells and the PVG polymer carrying reducing glucose moieties was suppressed by the inhibitors, phloretin, phloridzin, and cytochalasin B. Direct observation by confocal laser microscopy with the use of RITC-labeled PVG and pretreatment of HepG2 cells with the inhibitors demonstrated that the cells interacted with the soluble form of the PVG polymer via GLUT-1, while fluorescence labeling of the cell surface was prevented after pretreatment with the inhibitors of GLUT-1.

• Journal of Biosystems Engineering
• /
• 제39권2호
• /
• pp.111-114
• /
• 2014

Purpose: This review aims to introduce aptamers and the methods of its development to improve the sensitivity and selectivity to target bacteria. In this review, we have highlighted current developments and directions in the pathogen detection based on aptamers. Background: Aptamers, the specific nucleic acid sequences, can bind to targets with high affinity and specificity. Some of researches on the use of aptamers for the detection of pathogen have been reported in recent years. Aptamers have more applicability than antibodies for the development of pathogen detection using biosensor; such as easy to synthesis and labeling, lack of immunogenicity, and a low cost of production. However, only few reports on the development and use of aptamers for the detection of pathogen have been published. Review: Aptamers specific to pathogen are obtained by whole-cell systematic evolution of ligands by exponential enrichment (SELEX) process. SELEX process is composed of screening random oligonucleotide bound with target cells, multiple separation and amplification of nucleic acids, final identification of the best sequences. For improving those affinity and selectivity to target bacteria, optimization of multiple separating process to remove unbounded oligonucleotides from aptamer candidates and sorting process by flow cytometry are required.

• 한국응용약물학회:학술대회논문집
• /
• 한국응용약물학회 1995년도 춘계학술대회
• /
• pp.80-80
• /
• 1995

T4 Endonuclease V (Mw 16,000) acts as a repair enzyme for UV induced pyrimidine dimers in DNA. Many researchers have studied the biochemical characteristics of the enzyme. However the precise action mechanism of T4 endo V has not fully elucidated yet. In our laboratory NMR spectroscopy technique is being used for the structural study of T4 endo V. Because of its low temperature stability and high content of ${\alpha}$-helix, the conventional $^1$H NMR technique was inapplicable. Therefore we utilized stable isotope labeling technique and so far prepared about 10 amino acid specific labeled proteins. The HSQC spectra of amino acid specific labeled proteins will help us to interpret the triple resonance 3D, 4D data which are under processing, We also studied the behaviors of specific amino acid residues whose roles might be critical. When the enzyme labeled by $\^$15/N-Thr was mixed with the substrate oligonucleotide (semispecific -TT- sequence), one crosspeak in its HSQC spectrum was completely desappeared, which means that one of seven Thr residues is in the binding site of the enzyme with DNA, This result is well consistent with previous report that implicated the Thr 2 residue in the activity of the enzyme. Similar studies were carried on the behaviors of Arg and Tyr residues.

• Nuclear Medicine and Molecular Imaging
• /
• 제40권2호
• /
• pp.74-81
• /
• 2006

Molecular targeting may be defined as the specific concentration of a diagnostic or therapeutic tracer by its Interaction with a molecular species that is distinctly present or absent in a disease state. Monoclonal antibody (mAb) is one of the successful agents for targeted therapy in cancer. To enhance the therapeutic effect, the concept of targeting radionuclides to tumors using radiolabeled mAbs against tumor-associated antigens, radioimmunotherapy, was proposed. The efficacy of radioimmunotherapy, however, has to be further optimized. Several strategies to improve targeting of tumors with radiolabeled mAbs have been developed, such as the use of mAb fragments, the use of high-affinity mAbs, the use of labeling techniques that are stable in vivo, active removal of the radiolabeled mAb from the circulation, and pretargeting strategies. Until now, however, there are many kinds of obstacles to be solved in the use of mAb for the targeted therapy. Major technical challenges to molecular targeting are related to the rapid and specific delivery of tracers to the target, the elimination of unwanted background activity, and the development of more specific targets to create a cytocidal effect. further development of this field will be determined by success in solving these challenges.

• 대한핵의학회지
• /
• 제26권2호
• /
• pp.380-391
• /
• 1992

This study was designed to evaluate a direct method of $^{99m}Tc$ labeling using $\beta-mercaptoethanol$ as a reducing agent, and to investigate whether $^{99m}Tc$ labeled specific monoclonal antibody against carcinoembryonic antigen (CEA-92) can be used for the scintigraphic localization of human colon cancer xenograft. Purified CEA-92 IgG was fragmented into F $(ab')_2$ and then labeled with $^{99m}Tc$ by transchelation method using glucarate as a chelator. Labeling efficiency, immunological reactivity and in vitro stability of $^{99m}Tc$ CEA-92 F $(ab')_2$ were measured and then injected intravenously into nude mice bearing human colon cancer (SNU-C4). Scintigrams were obtained at 24 hour after injection. Then nude mice were sacrificed and the radioactivity was measured Labeling efficiency of injected $^{99m}Tc$ CEA-92 F $(ab')_2$, immunoreative fraction and in vitro stability at 24 hour of injected $^{99m}Tc$ CEA-92 F $(ab')_2$ was 45.2%, 32.8% and 57.4%, respectively. At 24 hour after injection, % ID/g in kidney (46.77) showed high uptake, but %ID/g in tumor (1.65) was significantly higher than spleen (0.69), muscle (0.16), intestine (0.45), stomach (0.75), heart (0.48) and blood (0.45). There was no significant difference between tumor and liver (1.81). Tumor contrast as quantitated by tumor to blood ratio of $^{99m}Tc$ CEA-92 F $(ab')_2$ was increased significantly (p<0.005) until 24 hours (3.70), and there was no statistical differece from tumor to blood ratio of I-131 CEA-92 F $(ab')_2$. The scintigram demonstrated localization of radioactivity over transplanted tumor, but significant background radioactivity was also noted over kidney and abdomen. It is concluded that CEA-92 F $(ab')_2$ can be labeled with $^{99m}Tc$ by a direct transchelation method using $\beta-mercaptoethanol$ as a reducing agent and $^{99m}Tc$ labeled CEA-92 F $(ab')_2$ can be used for the scintigraphic localization of human colon cancer xenograft in nude mice model.

• 한국식품위생안전성학회지
• /
• 제36권3호
• /
• pp.257-263
• /
• 2021

식품별 알레르기 유발물질 표시사항을 모니터링하기 위해 돼지고기, 우유 등 14개의 종 특이 프라이머를 이용한 유전자 검출법(PCR)을 실시하였다. 초등학교 근처 문구점과 수입과자판매점을 대상으로 알레르기 유발물질에 대한 표시사항이 없는 과자, 캔디류, 초콜릿류 등 60건에 대한 검사를 진행하였으며 그 중 30건에서 우유, 밀, 달걀, 토마토, 아몬드, 땅콩이 검출되었다. 특히 수입제품에서는 알레르기 유발물질을 표시하지 않았거나 한글 표시가 없는 경우도 확인되었으며, 표시 항목 이외의 물질이 검출되는 등 표시 사항이 미흡한 제품들이 다수 확인되었다. 소비자들이 안심하고 제품을 구매할 수 있도록 알레르기 유발물질 표시 사항에 대해 국내 제조가공업체와 수입관련 업체의 계도 및 감시 등 관련 기관 간의 긴밀한 협조 체계가 유지되어야 할 것이다.

• 한국축산식품학회지
• /
• 제30권3호
• /
• pp.403-409
• /
• 2010

Accurate methods for the identification of closely related species or breeds in raw and processed meats must be developed in order to protect both consumers and producers from mislabeling and fraud. This paper describes the development of DNA markers for the discrimination and improvement of Korean native pig (KNP) meat. The KIT gene is related to pig coat color and is often used as a candidate marker. A 538 bp fragment comprising intron 19 of the pig KIT gene was amplified by PCR using specific primers, after which the PCR amplicons of a number of meat samples from KNP and three major improved breeds (Landrace, Duroc and Yorkshire) were sequenced in order to find a nucleotide region suitable for PCR-RFLP analysis. Sequence data showed the presence of two nucleotide substitutions, g.276G>A and g.295A>C, between KNP and the improved pig breeds. Digestion of KIT amplicons with AccII enzyme generated characteristic PCR-RFLP profiles that allowed discrimination between meats from KNP and improved pig. KNP showed three visible DNA bands of 264/249, 199, and 75 bp, whereas DNA bands of 249, 199, and 90 bp were detected in the three improved pig breeds. Therefore, the 75 bp DNA fragment was specific only to KNP, whereas the 90 bp DNA fragment was specific to the improved breeds. The breed-specific DNA markers reported here that target the KIT gene could be useful for the identification of KNP meat from improved pig meats, thus contributing to the prevention of falsified breed labeling.