• Title/Summary/Keyword: Molecular techniques

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Some Molecular Characteristics and Improving Methods for Thermal Stability of Enzyme (효소단백질 열안정성의 분자구조적 특성 및 증진기법)

  • 김남수;김수일
    • Microbiology and Biotechnology Letters
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    • v.19 no.1
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    • pp.100-108
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    • 1991
  • Molecular characteristics and improving methods for thermal stability of enzyme have been considered. Intrinsic and extrinsic stabilizing mechanisms are two governing principles for enhanced thermal stability of enzyme in molecular basis. Factors contributing to the former and the latter mechanisms may be involved in the enhanced thermal stability of enzyme complementarily. Also, the methods for improving thermal stability of enzyme which comprise reaction in organic solvent system, chemical modification, immobilization, sequential unfolding and refolding, gene manipulation techniques and enzyme-antibody complexing are reviewed.

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Conductance Difference of Single Molecular Junctions between Experiments and Computational Simulations

  • Choi, Ji Il;Kim, Hu Sung;Kim, Young-Hoon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.184.2-184.2
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    • 2014
  • Recent advances in the synthesis and characterization of nanoscale objects provided us with the atomistic understanding of charge transport through single molecular junctions. The representative examples are the mechanically controlled break junction technique and STM or conducting AFM junction techniques. Theoretical studies have been reported on the dependence of electronic charge transport on the geometry of molecule-electrode contacts, the critical element toward the realization of molecular electronics. In this report, we will clarify the puzzling discrepancies between theoretical predictions and experiments.

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Microplate hybridization assay for detection of isoniazid resistance in Mycobacterium tuberculosis

  • Han, Hye-Eun;Lee, In-Soo;Hwang, Joo-Hwan;Bang, Hye-Eun;Kim, Yeun;Cho, Sang-Nae;Kim, Tae-Ue;Lee, Hye-Young
    • BMB Reports
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    • v.42 no.2
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    • pp.81-85
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    • 2009
  • Early and accurate detection of drug resistant Mycobacterium tuberculosis can improve both the treatment outcome and public health control of tuberculosis. A number of molecular-based techniques have been developed including ones using probe molecules that target drug resistance-related mutations. Although these techniques are highly specific and sensitive, mixed signals can be obtained when the drug resistant isolates are mixed with drug susceptible isolates. In order to overcome this problem, we developed a new drug susceptibility test (DST) for one of the most effective anti-tuberculosis drug, isoniazid. This technique employed a microplate hybridization assay that quantified signals from each probe molecule, and was evaluated using clinical isolates. The evaluation analysis clearly showed that the microplate hybridization assay was an accurate and rapid method that overcame the limitations of DST based on conventional molecular techniques.

Fibrolytic Rumen Bacteria: Their Ecology and Functions

  • Koike, Satoshi;Kobayashi, Yasuo
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.1
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    • pp.131-138
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    • 2009
  • Among rumen microbes, bacteria play important roles in the biological degradation of plant fiber due to their large biomass and high activity. To maximize the utilization of fiber components such as cellulose and hemicellulose by ruminant animals, the ecology and functions of rumen bacteria should be understood in detail. Recent genome sequencing analyses of representative fibrolytic bacterial species revealed that the number and variety of enzymes for plant fiber digestion clearly differ between Fibrobacter succinogenes and Ruminococcus flavefaciens. Therefore, the mechanism of plant fiber digestion is also thought to differ between these two species. Ecology of individual fibrolytic bacterial species has been investigated using pure cultures and electron microscopy. Recent advances in molecular biology techniques complement the disadvantages of conventional techniques and allow accurate evaluation of the ecology of specific bacteria in mixed culture, even in situ and in vivo. Molecular monitoring of fibrolytic bacterial species in the rumen indicated the predominance of F. succinogenes. Nutritive interactions between fibrolytic and non-fibrolytic bacteria are important in maintaining and promoting fibrolytic activity, mainly in terms of crossfeeding of metabolites. Recent 16S rDNA-based analyses suggest that presently recognized fibrolytic species such as F. succinogenes and two Ruminococcus species with fibrolytic activity may represent only a small proportion of the total fibrolytic population and that uncultured bacteria may be responsible for fiber digestion in the rumen. Therefore, characterization of these unidentified bacteria is important to fully understand the physiology and ecology of fiber digestion. To achieve this, a combination of conventional and modern techniques could be useful.

Imaging Evaluation of Peritoneal Metastasis: Current and Promising Techniques

  • Chen Fu;Bangxing Zhang;Tiankang Guo;Junliang Li
    • Korean Journal of Radiology
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    • v.25 no.1
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    • pp.86-102
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    • 2024
  • Early diagnosis, accurate assessment, and localization of peritoneal metastasis (PM) are essential for the selection of appropriate treatments and surgical guidance. However, available imaging modalities (computed tomography [CT], conventional magnetic resonance imaging [MRI], and 18fluorodeoxyglucose positron emission tomography [PET]/CT) have limitations. The advent of new imaging techniques and novel molecular imaging agents have revealed molecular processes in the tumor microenvironment as an application for the early diagnosis and assessment of PM as well as real-time guided surgical resection, which has changed clinical management. In contrast to clinical imaging, which is purely qualitative and subjective for interpreting macroscopic structures, radiomics and artificial intelligence (AI) capitalize on high-dimensional numerical data from images that may reflect tumor pathophysiology. A predictive model can be used to predict the occurrence, recurrence, and prognosis of PM, thereby avoiding unnecessary exploratory surgeries. This review summarizes the role and status of different imaging techniques, especially new imaging strategies such as spectral photon-counting CT, fibroblast activation protein inhibitor (FAPI) PET/CT, near-infrared fluorescence imaging, and PET/MRI, for early diagnosis, assessment of surgical indications, and recurrence monitoring in patients with PM. The clinical applications, limitations, and solutions for fluorescence imaging, radiomics, and AI are also discussed.

Looking Inside the Cell for Mechanisms of Immunotoxicity: Experimental Design and Approaches Aimed Toward Elucidation of 2,3,7,8-Tetrachlor- dibenzo-p-dioxin-mediated B Cell Dysfunction

  • Norbert E. Kaminski;Kang, Jong-Soon
    • Toxicological Research
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    • v.17
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    • pp.205-210
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    • 2001
  • One of the major focuses and perhaps the greatest challenges during the past decade in the discipline of immunotoxicology has been the elucidation of the molecular mechanisms responsible for immunotoxicity by specific agents. Much is currently understood about the basic underlying intracellular processes that control leukocyte effector function. This fundamental information in cell biology can now be applied toward developing systematic approaches, through the application of cell and molecular biology techniques, to identify the intracellular targets and processes disrupted by immunotoxicants. The objective of this paper is two fold. First to discuss fundamental principles of experimental design aimed at elucidation of cellular mechanisms in immunotoxicology; and second to discuss the application of molecular biology techniques in characterizing the mechanism of TCDD-induced B cell dysfunction as a working example.

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Breast Cancer in Morocco: A Literature Review

  • Slaoui, Meriem;Razine, Rachid;Ibrahimi, Azeddine;Attaleb, Mohammed;El Mzibri, Mohammed;Amrani, Mariam
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.3
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    • pp.1067-1074
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    • 2014
  • In Morocco, breast cancer is the most prevalent cancer in women and a major public health problem. Several Moroccan studies have focused on studying this disease, but more are needed, especially at the genetic and molecular levels. It is therefore interesting to establish the genetic and molecular profile of Moroccan patients with breast cancer. In this paper, we will highlight some pertinent hypotheses that may enhance breast cancer care in Moroccan patients. This review will give a precise description of breast cancer in Morocco and propose some new markers for detection and prediction of breast cancer prognosis.

Single Molecule Method for Molecular Biology

  • Kim, Jeong Hee;Jeong, Cherlhyun
    • International Journal of Oral Biology
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    • v.43 no.2
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    • pp.53-59
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    • 2018
  • 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.

Advances and Applications of Mass Spectrometry Imaging in Neuroscience: An Overview

  • Bharath S. Kumar
    • Mass Spectrometry Letters
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    • v.14 no.3
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    • pp.57-78
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    • 2023
  • Understanding the chemical composition of the brain helps researchers comprehend various neurological processes effectively. Understanding of the fundamental pathological processes that underpin many neurodegenerative disorders has recently advanced thanks to the advent of innovative bioanalytical techniques that allow high sensitivity and specificity with chemical imaging at high resolution in tissues and cells. Mass spectrometry imaging [MSI] has become more common in biomedical research to map the spatial distribution of biomolecules in situ. The technique enables complete and untargeted delineation of the in-situ distribution characteristics of proteins, metabolites, lipids, and peptides. MSI's superior molecular specificity gives it a significant edge over traditional histochemical methods. Recent years have seen a significant increase in MSI, which is capable of simultaneously mapping the distribution of thousands of biomolecules in the tissue specimen at a high resolution and is otherwise beyond the scope of other molecular imaging techniques. This review aims to acquaint the reader with the MSI experimental workflow, significant recent advancements, and implementations of MSI techniques in visualizing the anatomical distribution of neurochemicals in the human brain in relation to various neurogenerative diseases.

Development of new agrochemicals by quantitative structure-activity relationship (QSAR) methodology. III. 3D QSAR methodologies and computer-assisted molecular design (CAMD) (정량적인 구조-활성상관 (QSAR) 기법에 의한 새로운 농약의 개발. III. 3D QSAR 기법들과 컴퓨터를 이용한 분자설계(CAMD))

  • Sung, Nack-Do
    • The Korean Journal of Pesticide Science
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    • v.7 no.1
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    • pp.1-11
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    • 2003
  • Acoording to improvement of HTOS (high throughput organic synthesis) and HTS (high throughput screening) technique, the CoMFA (comparative molecular field analysis), CoMSIA (comparative molecular similarity indeces analysis) and molecular HQSAR (hologram quantitative structure-activity relationship) analysis techniques as methodology of computer assisted molecular design (CAMD) were introduced generally and summarized for some application cases.