• 제목/요약/키워드: Molecular techniques

검색결과 882건 처리시간 0.025초

Synthesis of Various Functional Block Copolymers via Controlled Ring Opening Metathesis Polymerization and the Subsequent Chemical Modifications

  • Kang, Min-Hyuk;Moon, Bong-Jin
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.200-200
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    • 2006
  • Several polynorbornene or poly(norbornene-7-oxide) based functional block copolymers were synthesized by ring opening metathesis polymerization (ROMP) with good molecular weight and polydispersity control. Some representative functional groups in these polymers are a nitrobenzoyl group or ferrocene. These polymers were subjected to various chemical modification reactions to give other block copolymers that contain novel functionality such as amine, diazonium salt, and diazo groups. The resulting polymers were characterized by various techniques such as GPC, NMR, UV-VIS, AFM, and cyclovotammography (CV).

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Gene Therapy for Oral Cancer

  • Chung, In-Jae
    • Biomolecules & Therapeutics
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    • 제15권4호
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    • pp.273-280
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    • 2007
  • New treatment approaches are needed to improve the effectiveness of oral cancer treatment, since surgical resection of the tumor in oral region causes various oral dysfunctions. The molecular biology of oral cancer has been progressively delineated. Concurrently, gene therapy techniques have been developed that allow targeting or replacement of dysfunctional genes in cancer cells, offering the potential to treat a wide range of cancer. Oral carcinoma is attractive target for gene therapy because of its accessibility. In this article, we review the current status of gene therapy as applied to oral carcinoma.

L-PHA 렉틴의 분리 정제및 면역학적 연구 (Purification and Immunochemical Studies on L-PHA Lectin)

  • 정시련;서영아;소명숙;전경희
    • 약학회지
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    • 제28권3호
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    • pp.139-147
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    • 1984
  • L-PHA, a lectin having lymphoagglutinating activity but devoid of erythroagglutinability which is contained in Korean white kidney bean (Phaseolus vulgaris L.), was isolated and purified through several techniques such as ion exchange chromatography, hydroxyapatite column and affinity chromatography. Purified L-PHA was identified as a single band by polyacrylamide disc gel electrophoresis. The molecular weight of the L-PHA was estimated about 125, 000 daltons by polyacrylamide gel electrophoresis and it was turned out having one subunit (probably dimer of the Yachnin's model) of Mr~60, 000. Immunochemical studies also tried and these results reconfirmed the purity of this L-PHA.

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Light-Microscopy-Based Sparse Neural Circuit Reconstruction: Array Tomography and Other Methods

  • Rah, Jong-Cheol
    • Applied Microscopy
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    • 제46권4호
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    • pp.176-178
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    • 2016
  • Efficient neural circuit reconstruction requires sufficient lateral and axial resolution to resolve individual synapses and map a large enough volume of brain tissue to reveal the molecular identity and origin of these synapses. Sparse circuit reconstruction using array tomography meets many of these requirements but also has some limitations. In this minireview, the advantages and disadvantages of applicable imaging techniques will be discussed.

Neural and Genetic Basis of Evasion, Approach and Predation

  • Park, Seahyung;Ryoo, Jia;Kim, Daesoo
    • Molecules and Cells
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    • 제45권2호
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    • pp.93-97
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    • 2022
  • Evasion, approach and predation are examples of innate behaviour that are fundamental for the survival of animals. Uniting these behaviours is the assessment of threat, which is required to select between these options. Far from being comprehensive, we give a broad review over recent studies utilising optic techniques that have identified neural circuits and genetic identities underlying these behaviours.

하천수 내 생물학적 안정성에 따른 유기물 특성변화와 오존산화기반 전처리 연구 (Biological stability in the ozone and peroxone pretreatment systems in river water)

  • 박세희;노진형;박지원;맹승규
    • 상하수도학회지
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    • 제32권2호
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    • pp.159-168
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    • 2018
  • Climate change is believed to increase the amount of dissolved organic matter in surface water, as a result of the release of bulk organic matter, which make difficult to achieve a high quality of drinking water via conventional water treatment techniques. Therefore, the natural water treatment techniques, such as managed aquifer recharge (MAR), can be proposed as a alternative method to improve water quality greatly. Removal of bulk organic matter using managed aquifer recharge system is mainly achieved by biodegradation. Biodegradable dissolved organic carbon (BDOC) and assimilable organic carbon (AOC) can be used as water quality indicators for biological stability of drinking water. In this study, we compared the change of BDOC and AOC with respect to pretreatment methods (i.e., ozone or peroxone). The oxidative pretreatment can transform the recalcitrant organic matter into readily biodegradable one (i.e., BDOC and AOC). We also investigated the differences of organic matter characteristics between BDOC and AOC. We observed the decreases in dissolved organic carbon (DOC) and the tryptophan-like fluorescence intensities. Liquid chromatographic - organic carbon detection (LC-OCD) analysis also showed the reduction of the low molecular weight (LMW) fraction (15% removed, less than 500 Da), which is known to be easily biodegradable, and the biopolymers, high molecular weight fractions (66%). Therefore, BDOC consists of a broad range of organic matter characteristics with respect to molecular weight. In AOC, low molecular weight organic matter and biopolymers fraction was reduced by 11 and 6%, respectively. It confirmed that biodegradation by microorganisms as the main removal mechanism in AOC, while BDOC has biodegradation by microorganism as well as the sorption effects from the sand. $O_3$ and $O_3+H_2O_2$ were compared with respect to biological stability and dissolved organic matter characteristics. BDOC and AOC were determined to be about 1.9 times for $O_3$ and about 1.4 times for $O_3+H_2O_2$. It was confirmed that $O_3$ enhanced the biodegradability by increasing LMW dissolved organic matter.

SARS-CoV-2의 진단기술 (Diagnostic Techniques for SARS-CoV-2 Detection)

  • 김종식;강나경;박선미;이은주;정경태
    • 생명과학회지
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    • 제30권8호
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    • pp.731-741
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    • 2020
  • 코로나바이러스감염증-19(COVID-19)는 SARS-CoV-2에 의해 발병된다. 지금까지 인간에게 감염되는 7 가지 종류의 코로나 바이러스가 보고되었다. 그 중, HCoV-229E, HCoV-OC43, HCoV-NL63, 그리고 HCoV-HKU1 등 4종류의 코로나바이러스는 감기와 같은 단순 호흡기 질환을 유발한다고 보고되었다. 반면, SARS-CoV는 2002년에, MERS-CoV는 2012년에 각각 대유행을 일으킨 바 있다. 가장 최근에는 2019년 12월 중국 우한에서 처음 보고된 SARS-CoV-2가 전세계적인 대유행의 원인이 되고 있다. 이러한 SARS-CoV-2를 진단하고, 치료하고, 예방하기 위해서는 신속 정확한 진단키트, 치료제, 그리고 안전한 백신의 개발의 필수적으로 요구된다. 이러한 강력한 도구들을 개발하기 위해서는 SARS-CoV-2의 표현형, 유전자형, 그리고 생활주기 등의 연구가 선행되어야 한다. SARS-CoV-2의 진단기술은 현재 크게 두가지의 큰 분야인 분자진단과 면역혈청학적 진단으로 구분할 수 있다. 분자진단의 경우 SARS-CoV-2의 유전체를 대상으로 하며, 면역혈청학적 진단은 SARS-CoV-2의 항원 단백질 혹은 SARS-CoV-2에 대한 항체를 대상으로 한다. 본 총설에서는 SARS-CoV-2의 표현형, 유전체 구조, 그리고 유전자 발현에 대해서 정리하고, SARS-CoV-2에 대한 다양한 진단 기술 등에 대한 기초지식을 제공하고자 한다.

Cellular and Molecular Pathology of Fungi on Plants Studied by Modern Electron Microscopy

  • Sanwald, Sigrun-Hippe
    • 한국식물병리학회:학술대회논문집
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    • 한국식물병리학회 1995년도 Proceedings of special lectures on Molecular Biological Approaches to Plant Disease National Agricultural Science and Technology Institute Suwon, Korea
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    • pp.27-53
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    • 1995
  • In plant pathology there is an increasing necessity for improved cytological techniques as basis for the localization of cellular substances within the dynamic fine structure of the host-(plant)-pathogen-interaction. Low temperature (LT) preparation techniques (shock freezing, freeze substitution, LT embedding) are now successfully applied in plant pathology. They are regarded as important tools to stabilize the dynamic plant-pathogen-interaction as it exists under physiological conditions. - The main advantage of LT techniques versus conventional chemical fixation is seen in the maintenance of the hydration shell of molecules and macromolecular structures. This results in an improved fine structural preservation and in a superior retention of the antigenicity of proteins. - A well defined ultrastructure of small, fungal organisms and large biological samples such as plant material and as well as the plant-pathogen (fungus) infection sites are presented. The mesophyll tissue of Arabidopsis thaliana is characterized by homogeneously structured cytoplasm closely attached to the cell wall. From analyses of the compatible interaction between Erysiphe graminis f. sp. hordei on barley (Hordeum vulgare), various steps in the infection sequence can be identified. Infection sites of powdery mildew on primary leaves of barley are analysed with regard to the fine structural preservation of the haustoria. The presentation s focussed on the ultrastructure of the extrahaustorial matrix and the extrahaustorial membrane. - The integration of improved cellular preservation with a molecular analysis of the infected host cell is achieved by the application of secondary probing techniques, i.e. immunocytochemistry. Recent data on the characterization of freeze substituted powdery mildew and urst infected plant tissue by immunogold methodology are described with special emphasis on the localization of THRGP-like (threonine-hydrxyproline-rich glycoprotein) epitopes. Infection sites of powdery mildew on barley, stem rust as well as leaf rust (Puccinia recondita) on primary leaves of wheat were probed with a polyclonal antiserum to maize THRGP. Cross-reactivity with the anti-THRGP antiserum was observed over the extrahaustorial matrix of the both compatible and incompatible plant-pathogen interactions. The highly localized accumulation of THRGP-like epitopes at the extrahaustorial host-pathogen interface suggests the involvement of structural, interfacial proteins during the infection of monocotyledonous plants by obligate, biotrophic fungi.

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PHA-Induced Peripheral Blood Cytogenetics and Molecular Anslysis : a Valid Diagnostic and Follow-up Modality For Acute Primyelocytic Leukemia Patients Treated With ATRA and/or Arsenic Tri-oxide

  • Baba, Shahid M;Azad, Niyaz A;Shah, Zaffar A;Afroze, Dil;Pandith, Arshad A;Jan, Aleem;Aziz, Sheikh A;Dar, Fayaz A
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권4호
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    • pp.1999-2006
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    • 2016
  • Background: Acute promyelocytic leukemia (APML) is characterized by the reciprocal translocation t(15;17) (p22;p12) resulting in the PML-$RAR{\alpha}$ fusion gene. A dual diagnostic and follow up approach was applied including cytogenetic demonstration of the t(15;17) translocation and detection dg PML-$RAR{\alpha}$ chimeric transcripts by molecular means. Purpose: Conventional cytogenetics involving bone marrow is beset with high probability of poor metaphase index and was substituted with phytohemagglutinin (PHA)-induced peripheral blood culture based cytogenetic analysis as a diagnostic & follow up modality in APML patients of Kashmir (North India). Both qualitative (RT-PCR) and quantitative (Q-PCR) tests were simultaneously carried out to authenticte the modified cytogenetics. Materials and Method: Patient samples were subjected to the said techniques to establish their baseline as well as follow-up status. Results: Initial cytogenetics revealed 30 patients (81%) Positive for t(15;17) whereas 7 (19%) had either cryptic translocation or were negative for t(15;17). Two cases had chromosome 16q deletion and no hallmark translocation t(15;17). Q-PCR status for PML-$RAR{\alpha}$ was found to be positive for all patients. All the APML patients were reassessed at the end of consolidation phase and during maintenance phase of chemotherapy where 6 patients had molecular relapse, wherein 4 also demonstrated cytogenetic relapse. Conclusions: It was found that PHA-induced peripheral blood cytogenetics along with molecular analysis could prove a reliable modality in the diagnosis and assessment of follow up response of APML patients.

Nano Bio Imaging for NT and BT

  • Moon, DaeWon
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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    • pp.51.2-51.2
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    • 2015
  • Understanding interfacial phenomena has been one of the main research issues not only in semiconductors but only in life sciences. I have been trying to meet the atomic scale surface and interface analysis challenges from semiconductor industries and furthermore to extend the application scope to biomedical areas. Optical imaing has been most widely and successfully used for biomedical imaging but complementary ion beam imaging techniques based on mass spectrometry and ion scattering can provide more detailed molecular specific and nanoscale information In this presentation, I will review the 27 years history of medium energy ion scattering (MEIS) development at KRISS and DGIST for nanoanalysis. A electrostatic MEIS system constructed at KRISS after the FOM, Netherland design had been successfully applied for the gate oxide analysis and quantitative surface analysis. Recenlty, we developed time-of-flight (TOF) MEIS system, for the first time in the world. With TOF-MEIS, we reported quantitative compositional profiling with single atomic layer resolution for 0.5~3 nm CdSe/ZnS conjugated QDs and ultra shallow junctions and FINFET's of As implanted Si. With this new TOF-MEIS nano analysis technique, details of nano-structured materials could be measured quantitatively. Progresses in TOF-MEIS analysis in various nano & bio technology will be discussed. For last 10 years, I have been trying to develop multimodal nanobio imaging techniques for cardiovascular and brain tissues. Firstly, in atherosclerotic plaque imaging, using, coherent anti-stokes raman scattering (CARS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) multimodal analysis showed that increased cholesterol palmitate may contribute to the formation of a necrotic core by increasing cell death. Secondly, surface plasmon resonance imaging ellipsometry (SPRIE) was developed for cell biointerface imaging of cell adhesion, migration, and infiltration dynamics for HUVEC, CASMC, and T cells. Thirdly, we developed an ambient mass spectrometric imaging system for live cells and tissues. Preliminary results on mouse brain hippocampus and hypotahlamus will be presented. In conclusions, multimodal optical and mass spectrometric imaging privides overall structural and morphological information with complementary molecular specific information, which can be a useful methodology for biomedical studies. Future challenges in optical and mass spectrometric imaging for new biomedical applications will be discussed.

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