• Asian-Australasian Journal of Animal Sciences
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• v.20 no.12
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• pp.1887-1894
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• 2007

In this paper, a rapid and reliable gene-targeted species-specific polymerase chain reaction (PCR) technique based on a two-step process was established to identify bifidobacteria in dairy products. The first step was the PCR assay for genus Bifidobacterium with genus specific primers followed by the second step, which identified the species level with species-specific primer mixtures. Ten specific primer pairs, designed from nucleotide sequences of the 16-23S rRNA region, were developed for the Bifidobacterium species including B. angulatum, B. animalis, B. bifidum, B. breve, B. catenulatum, B. infantis, B. longum, B. minimum, B. subtile, and B. thermophilum. This technique was applied to the identification of Bifidobacterium species isolated from 6 probiotic products, and four different Bifidobacterium spp. (B. bifidum, B. longum, B. infantis, and B. breve) were identified. The findings indicated that the 16S-23S rDNA gene-targeted species-specific PCR technique is a simple and reliable method for identification of bifidobacteria in probiotic products. PCR combined with Denaturing Gradient Gel Electrophoresis (DGGE) for identification of the bifidobacteria was also evaluated and compared with the gene-targeted species-specific technique. Results indicated that for fermented milk products consistency was found for both species-specific PCR and PCR-DGGE in detecting species. However, in some lyophilized products, the bands corresponding to these species were not visualized in the DGGE profile but the specific PCR gave a positive result.

• Proceedings of the ESK Conference
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• 1996.10a
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• pp.197-205
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• 1996

Unification of neural network with a hierarchical pattern recognition is presented for recognizing large set of objects. A two-step identification procedure is developed for pattern recognition: coarse and fine identification. The coarse identification is designed for finding a class of object while the fine identification procedure is to identify a specific object. During the training phase a course neural network is trained for clustering larger set of reference objects into a number of groups. For training a fine neural network, expert neural network is also trained to identify a specific object within a group. The presented idea can be interpreted as two step identification. Experimental results are given to verify the proposed methodology.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.5
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• pp.1755-1777
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• 2022

The development of wireless communication technology has led to the underutilization of radio spectra. To address this limitation, an intelligent cognitive radio network was developed. Specific emitter identification (SEI) is a key technology in this network. However, in realistic non-cooperative scenarios, the system may detect signal classes beyond those in the training database, and only a few labeled signal samples are available for network training, both of which deteriorate identification performance. To overcome these challenges, a meta-learning-based open-set identification system is proposed for SEI. First, the received signals were pre-processed using bi-spectral analysis and a Radon transform to obtain signal representation vectors, which were then fed into an open-set SEI network. This network consisted of a deep feature extractor and an intrinsic feature memorizer that can detect signals of unknown classes and classify signals of different known classes. The training loss functions and the procedures of the open-set SEI network were then designed for parameter optimization. Considering the few-shot problems of open-set SEI, meta-training loss functions and meta-training procedures that require only a few labeled signal samples were further developed for open-set SEI network training. The experimental results demonstrate that this approach outperforms other state-of-the-art SEI methods in open-set scenarios. In addition, excellent open-set SEI performance was achieved using at least 50 training signal samples, and effective operation in low signal-to-noise ratio (SNR) environments was demonstrated.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.205-209
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• 2003

Recently, we introduced a new method for rapid screening of bacterial species- or subspecies-specific DNA probes, named “inverted dot blot hybridization screening method”. We then applied this method to develop species- or strain- specific DNA probes for Prevotella intermedia and Prevotella nigrescens. In those studies, among 96 candidate DNA probes which were screened by the new method, 5 probes were confirmed as being putatively strain-specific : 3 probes for P. nigrescens 9336 (ATCC 33563), one for each p. intermedia ATCC 25611 and one for P. nigrescens G8-9K-3 (ATCC 49046). In the present study, we evaluated by Southern blot analysis a DNA probe Pi29-L, one of the 96 candidate probes described above, whether it is specific for the strain ATCC 25611 off. intermedia. Our data show that the probe Pi29-L is potentially P. intermedia ATCC 25611-specific, which can be useful for the detection and identification of the strain, particularly in maintenance of the strain.

• KIPS Transactions on Software and Data Engineering
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• v.10 no.12
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• pp.547-554
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• 2021

Cancer patients can have different kinds of cancer driver genes, and identification of these patient-specific cancer driver genes is an important step in the development of personalized cancer treatment and drug development. Several bioinformatic methods have been proposed for this purpose, but there is room for improvement in terms of accuracy. In this paper, we propose NPD (Network based Patient-specific Driver gene identification) for identifying patient-specific cancer driver genes. NPD consists of three steps, constructing a patient-specific gene network, applying the modified PageRank algorithm to assign scores to genes, and identifying cancer driver genes through a score comparison method. We applied NPD on six cancer types of TCGA data, and found that NPD showed generally higher F1 score compared to existing patient-specific cancer driver gene identification methods.

• Fisheries and Aquatic Sciences
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• v.26 no.11
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• pp.678-688
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• 2023

Flatfish are one of the largest families in the order Pleuronectiformes and are economically important edible marine fish species. However, they have similar morphological characteristics leading to challenges in classifying correctly, which may result in mislabeling and illegal sales, such as fraudulent labeling of processed food. Therefore, accurate identification is important to ensure the quality and safety of domestic markets in Korea. Species-specific primers were prepared from the mainly consumed eleven species of the order Pleuronectiformes. To rapidly identify the 11 flatfish species, a highly efficient, rapid, multiplex polymerase chain reaction (PCR) with species-specific primers was developed. Species-specific primer sets were designed for the mitochondrial DNA cytochrome c oxidase subunit I gene. Species-specific multiplex PCR (MSS-PCR) either specifically amplified a PCR product of a unique size or failed. This MSS-PCR analysis is easy to perform and yields reliable results in less time than the previous Sanger sequencing methods. This technique could be a powerful tool for the identification of the 11 species b the family Pleuronectidae and can contribute to the prevention of falsified labeling and protection of consumer rights.

• Mycobiology
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• v.31 no.4
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• pp.196-199
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• 2003

A very reliable and specific method for the identification of fungi in ectotrophic mycorrhizal symbiosis was developed using a specific PCR assay based on the amplification of the ITS1 region. To obtain specific data, an ITS-diagnostic assay was carried out that reveals genera and species specific sequences. Here, an application of one method is presented, which covers the identification of pure mycelia, basidiocarps as well as mixed samples such as ectomycorrhizal roots that were mingled with remains of the host plant. For this purpose a protocol was established that allowed the extraction of DNA from single mycorrhizal roots. In order to perform a specific ITS analysis we generated a new ITS-primer(ITS8) by a multiple alignment of five different genera and species of mycorrhizal fungi. The utilization of ITS1 and ITS8 resulted in specific PCR amplicons, which were characterized by sequencing without purification steps, even when the template DNA was associated with roots.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.4 no.4
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• pp.154-158
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• 2023

The Asiatic black bear, Ursus thibetanus, is among the most threatened or endangered species in Asia. For its conservation and management, sex identification of U. thibetanus using non-invasive samples (e.g., hair and/or feces) is potentially valuable. In this study, a non-invasive molecular method for sex identification of U. thibetanus samples collected from various countries was first utilized, and it was based on polymerase chain reaction (PCR) amplification of the amelogenin gene via PCRs. Thirty-three bear DNA samples, extracted not only from blood (n=9) but also from hair (n=18) and feces (n=6), were used. We performed sex-specific PCR amplifications of the amelogenin gene using a primer set, SE47 and SE48. The primer set could successfully amplify a single X-specific band for females and both X- and Y-specific bands for males from all blood (100%) and hair (100%) samples. In addition, the primer set could distinguish the sex of bears in four out of a total of six fecal samples (approximately 67%). This study's findings suggest that this molecular method can be applied to sex identification of Asiatic black bears from various Asian regions using non-invasive samples, such as hair and feces.

• Development and Reproduction
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• v.23 no.4
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• pp.367-375
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• 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
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• v.27 no.5
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• pp.909-915
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• 2017

Bifidobacterium bifidum BGN4 (BGN4) has many proven beneficial effects, including antiallergy and anticancer properties. It has been commercialized and used in several probiotic products, and thus strain-specific identification of this strain is very valuable for further strain-dependent physiological study. For this purpose, we developed novel multiplex polymerase chain reaction (PCR) primer sets for strain-specific detection of BGN4 in commercial products and fecal samples of animal models. The primer set was tested on seven strains of B. bifidum and 75 strains of the other Bifidobacterium species. The BGN4-specific regions were derived using megaBLAST against genome sequences of various B. bifidum databases and four sets of primers were designed. As a result, only BGN4 produced four PCR products simultaneously whereas the other strains did not. The PCR detection limit using BGN4-specific primer sets was $2.8{\times}10^1CFU/ml$ of BGN4. Those primer sets also detected and identified BGN4 in the probiotic products containing BNG4 and fecal samples from a BGN4-fed animal model with high specificity. Our results indicate that the PCR assay from this study is an efficient tool for the simple, rapid, and reliable identification of BGN4, for which probiotic strains are known.