• 제목/요약/키워드: sequences

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Phantom-Validated Reference Values of Myocardial Mapping and Extracellular Volume at 3T in Healthy Koreans

  • Lee, Eunjin;Kim, Pan Ki;Choi, Byoung Wook;Jung, Jung Im
    • Investigative Magnetic Resonance Imaging
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    • 제24권3호
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    • pp.141-153
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    • 2020
  • Purpose: Myocardial T1 and T2 relaxation times are affected by technical factors such as cardiovascular magnetic resonance platform/vendor. We aimed to validate T1 and T2 mapping sequences using a phantom; establish reference T1, T2, and extracellular volume (ECV) measurements using two sequences at 3T in normal Koreans; and compare the protocols and evaluate the differences from previously reported measurements. Materials and Methods: Eleven healthy subjects underwent cardiac magnetic resonance imaging (MRI) using 3T MRI equipment (Verio, Siemens, Erlangen, Germany). We did phantom validation before volunteer scanning: T1 mapping with modified look locker inversion recovery (MOLLI) with 5(3)3 and 4(1)3(1)2 sequences, and T2 mapping with gradient echo (GRE) and TrueFISP sequences. We did T1 and T2 mappings on the volunteers with the same sequences. ECV was also calculated with both sequences after gadolinium enhancement. Results: The phantom study showed no significant differences from the gold standard T1 and T2 values in either sequence. Pre-contrast T1 relaxation times of the 4(1)3(1)2 protocol was 1142.27 ± 36.64 ms and of the 5(3)3 was 1266.03 ± 32.86 ms on the volunteer study. T2 relaxation times of GRE were 40.09 ± 2.45 ms and T2 relaxation times of TrueFISP were 38.20 ± 1.64 ms in each. ECV calculation was 24.42% ± 2.41% and 26.11% ± 2.39% in the 4(1)3(1)2 and 5(3)3 protocols, respectively, and showed no differences at any segment or slice between the sequences. We also calculated ECV from the pre-enhancement T1 relaxation time of MOLLI 5(3)3 and the post-enhancement T1 relaxation time of MOLLI 4(1)3(1)2, with no significant differences between the combinations. Conclusion: Using phantom-validated sequences, we reported the normal myocardial T1, T2, and ECV reference values of healthy Koreans at 3T. There were no statistically significant differences between the sequences, although it has limited statistical value due to the small number of subjects studied. ECV showed no significant differences between calculations based on various pre- and post-mapping combinations.

Construction of web-based Database for Haliotis SNP (웹기반 전복류 (Haliotis) SNP 데이터베이스 구축)

  • Jeong, Ji-Eun;Lee, Jae-Bong;Kang, Se-Won;Baek, Moon-Ki;Han, Yeon-Soo;Choi, Tae-Jin;Kang, Jung-Ha;Lee, Yong-Seok
    • The Korean Journal of Malacology
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    • 제26권2호
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    • pp.185-188
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    • 2010
  • The Web-based the genus Haliotis SNP database was constructed on the basis of Intel Server Platform ZSS130 dual Xeon 3.2 GHz cpu and Linux-based (Cent OS) operating system. Haliotis related sequences (2,830 nucleotide sequences, 9,102 EST sequences) were downloaded through NCBI taxonomy browser. In order to eliminate vector sequences, we conducted vector masking step using cross match software with vector sequence database. In addition, poly-A tails were removed using Trimmest software from EMBOSS package. The processed sequences were clustered and assembled by TGICL package (TIGR tools) equipped with CAP3 software. A web-based interface (Haliotis SNP Database, http://www.haliotis.or.kr) was developed to enable optimal use of the clustered assemblies. The Clustering Res. menu shows the contig sequences from the clustering, the alignment results and sequences from each cluster. And also we can compare any sequences with Haliotis related sequences in BLAST menu. The search menu is equipped with its own search engine so that it is possible to search all of the information in the database using the name of a gene, accession number and/or species name. Taken together, the Web-based SNP database for Haliotis will be valuable to develop SNPs of Haliotis in the future.

Terminal Nucleotide Sequences in the Double-stranded RNA Genome Segments of Infectious Pancreatic Necrosis Virus DRT Strain

  • Chung, Hye-Kyung;Park, Hong-Chul;Ichiro Uyeda;Masamichi Isogai;Lee, Hyung-Hoan
    • Journal of Microbiology and Biotechnology
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    • 제6권5호
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    • pp.361-363
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    • 1996
  • The terminal regions of the double-stranded RNA (dsRNA) genome segments of infectious pancreatic necrosis virus (IPNV) DRT strain were sequenced. The dsRNAs, which were $^{32}P$-labelled at their 3'-termini by incubation with [$^{32}P$]pCp and T4 RNA ligase, were separated by 5$%$ polyacrylamide gel electrophoresis, and the segments A and B of IPNV-DRT were sequenced by two-dimensional gel electrophoresis. The 5'-terminal sequences of the IPNV-DRT plus strand from two genome segments were found to have the same conserved nucleotide (5'-CGG(C/A)A-), but the 3'-terminal sequences -CCCCAGGCG-3' and -CGGACCCCG-3' were found in the plus strand from segments A and B, respectively. The inverted oligonucleotide sequences of 3'-terminal of between segments A and B were found and they differ from those of other IPNVs.

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Retrieving Protein Domain Encoding DNA Sequences Automatically Through Database Cross-referencing

  • Choi, Yoon-Sup;Yang, Jae-Seong;Ryu, Sung-Ho;Kim, Sang-Uk
    • Bioinformatics and Biosystems
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    • 제1권2호
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    • pp.95-98
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    • 2006
  • Recent proteomic studies of protein domains require high-throughput and systematic approaches. Since most experiments using protein domains, the modules of protein-protein interactions, require gene cloning, the first experimental step should be retrieving DNA sequences of domain encoding regions from databases. For a large scale proteomic research, however, it is a laborious task to extract a large number of domain sequences manually from several inter-linked databases. We present a new methodology to retrieve DNA sequences of domain encoding regions through automatic database cross-referencing. To extract protein domain encoding regions, it traverses several inter-connected database with validation process. And we applied this method to retrieve all the EGF domain encoding DNA sequences of homo sapiens. This new algorithm was implemented using Python library PAMIE, which enables to cross-reference across distinct databases automatically.

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Categorizing accident sequences in the external radiotherapy for risk analysis

  • Kim, Jonghyun
    • Radiation Oncology Journal
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    • 제31권2호
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    • pp.88-96
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    • 2013
  • Purpose: This study identifies accident sequences from the past accidents in order to help the risk analysis application to the external radiotherapy. Materials and Methods: This study reviews 59 accidental cases in two retrospective safety analyses that have collected the incidents in the external radiotherapy extensively. Two accident analysis reports that accumulated past incidents are investigated to identify accident sequences including initiating events, failure of safety measures, and consequences. This study classifies the accidents by the treatments stages and sources of errors for initiating events, types of failures in the safety measures, and types of undesirable consequences and the number of affected patients. Then, the accident sequences are grouped into several categories on the basis of similarity of progression. As a result, these cases can be categorized into 14 groups of accident sequence. Results: The result indicates that risk analysis needs to pay attention to not only the planning stage, but also the calibration stage that is committed prior to the main treatment process. It also shows that human error is the largest contributor to initiating events as well as to the failure of safety measures. This study also illustrates an event tree analysis for an accident sequence initiated in the calibration. Conclusion: This study is expected to provide sights into the accident sequences for the prospective risk analysis through the review of experiences.

An Efficient Approach to Mining Maximal Contiguous Frequent Patterns from Large DNA Sequence Databases

  • Karim, Md. Rezaul;Rashid, Md. Mamunur;Jeong, Byeong-Soo;Choi, Ho-Jin
    • Genomics & Informatics
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    • 제10권1호
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    • pp.51-57
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    • 2012
  • Mining interesting patterns from DNA sequences is one of the most challenging tasks in bioinformatics and computational biology. Maximal contiguous frequent patterns are preferable for expressing the function and structure of DNA sequences and hence can capture the common data characteristics among related sequences. Biologists are interested in finding frequent orderly arrangements of motifs that are responsible for similar expression of a group of genes. In order to reduce mining time and complexity, however, most existing sequence mining algorithms either focus on finding short DNA sequences or require explicit specification of sequence lengths in advance. The challenge is to find longer sequences without specifying sequence lengths in advance. In this paper, we propose an efficient approach to mining maximal contiguous frequent patterns from large DNA sequence datasets. The experimental results show that our proposed approach is memory-efficient and mines maximal contiguous frequent patterns within a reasonable time.

Characterization and Phylogenetic Analysis of Chitin Synthase Genes from the Genera Sporobolomyces and Bensingtonia subrorea

  • Nam, Jin-Sik
    • Korean Journal of Environmental Biology
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    • 제23권4호
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    • pp.335-342
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    • 2005
  • We cloned seven genes encoding chitin synthases (CHSs) by PCR amplification from genomic DNAs of four strains of the genus Sporobolomyces and of Bensingtonia subrosea using degenerated primers based on conserved regions of the CHS genes. Though amino acid sequences of these genes were shown similar as 176 to 189 amino acids except SgCHS2, DNA sequences were different in size, which was due to various introns present in seven fragments. Alignment and phylogenetic analysis of their deduced amino acid sequences together with the reported CHS genes of basidiomycetes separated the sequences into classes I, II and III. This analysis also permitted the classification of isolated CHSs; SgCHS1 belongs to class I, BsCHS1, SaCHS1, SgCHS2, SpgCHS1, and SsCHS1 belong to class II, and BsCHS2 belongs to class III. The deduced amino acid sequences involving in class II that were discovered from five strains were also compared with those of other basidiomycetes by CLUSTAL X program. The bootstrap analysis and phylogenetic tree by neighbor-joining method revealed the taxonomic and evolutionary position for four strains of the genus Sporobolomyces and for Bensingtonia subrosea which agreed with the previous classification. The results clearly showed that CHS fragments could be used as a valuable key for the molecular taxonomic and phylogenetic studies of basidiomycetes.

Diversity Census of Fecal Microbiome in Horses (말 분변 내 마이크로바이옴 다양성 조사)

  • Lee, Seul;Kim, Minseok
    • Journal of Animal Reproduction and Biotechnology
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    • 제34권3호
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    • pp.157-165
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    • 2019
  • This study was conducted to analyze the diversity census of fecal microbiome in horses using meta-analysis of equine 16S rRNA gene sequences that are available in the Ribosomal Database Project (RDP; Release 11, Update 5). The search terms used were "horse feces (or faeces)" and "equine feces (or faeces)". A total of 842 sequences of equine feces origin were retrieved from the RDP database, where 744 sequences were assigned to 10 phyla placed within Domain Bacteria. Firmicutes (n = 391) and Bacteroidetes (n = 203) were the first and the second dominant phyla, respectively, followed by Verrucomicrobia (n = 58), Proteobacteria (n = 30) and Fibrobacteres (n = 24). Clostridia (n = 319) was the first dominant class placed within Bacteroidetes while Bacteroidia (n = 174) was the second dominant class placed within Bacteroidetes. The remaining 98 sequences were assigned to phylum Euryarchaeota placed within Domain Archaea, where 74 sequences were assigned to class Methanomicrobia. The current results will improve understanding of the diversity of fecal microbiome in horses and may be used to further analyze equine fecal microbiome in future studies.

Trap identification of the constitutive promoter-like sequences from the bacterial fish pathogen, as exemplified by Edwardsiella tarda

  • Lee, Sang-Yoon;Kim, Ki-Hong;Kim, Dong-Soo;Nam, Yoon-Kwon
    • Journal of fish pathology
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    • 제24권3호
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    • pp.297-305
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    • 2011
  • A trap identification system for isolating functional sequences to allow the constitutive expression of foreign protein from Edwardsiella tarda was developed. Using the green fluorescent protein (GFP) reporter-based trap system, various functional sequences to drive heterologous expression of the GFP were selectable in Escherichia coli host. However from the bioinformatic sequence analysis, all the segments predicted as regulatory regions were not native promoters actually existing upstream of endogenous E. tarda genes. Instead, a number of non-authentic sequences, possibly resulted from the random shuffling and/or intermolecular ligation were also proven to be able to display a potent GFP expression in the recombinant E. coli. Further analysis with selected clones showed that both authentic and non-authentic sequences could function in as a constitutive promoter, leading quite a consistent and stable GFP expression after repetitive subcultures. Microscopic examination also confirmed the uniform pattern of GFP expression in every host bacterium. Semi-quantitative assay of GFP showed that there was no clear relationship between expression levels and organizational features of the promoters trapped. Functional promoter-like elements achieved in the present study could be a good starting material for multivalent genetic engineering of E. tarda in order to produce recombinant vaccines in a cost-effective fashion.