• Title/Summary/Keyword: Phylogenetic study

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What Characteristics Do Preservice Teachers Show During Trilobite Classification Activities? (예비교사들은 삼엽충 분류활동 중에 어떤 특성을 보이는가?)

  • Lim, Sungman
    • Journal of the Korean Society of Earth Science Education
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    • v.12 no.1
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    • pp.40-53
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    • 2019
  • This study was to analyze the inquiry characteristics of preservice teachers as they classify trilobites. For the study, 70 preservice teachers attending teacher training university participated. The classification tasks used in the study were 9 photos of trilobite fossils. The preservice teachers' inquiry activity was to classify the evolutionary processes of trilobites after observing trilobite fossils by group and then to construct a phylogenetic tree. The results of the study are as follows. First, preservice teachers observed the external features of the trilobites and constructed systematic classification results based on their observed contents. Second, preservice teachers classified trilobites using various classification criteria. Third, the phylogenetic tree of preservice teachers and the phylogenetic tree of scientists were very similar. The preservice teachers constructed a sphylogenetic tree based on the observation and inference of the change from a simple form to a complex form, which is a general evolution process of the trilobite fossil claimed by scientists. These results suggest that group-based inquiry activities with sufficient time are very effective and that the experience of inquiry activities is very important for preservice teachers.

Molecular Phylogenetics of Trichostrongylus Species (Nematoda: Trichostrongylidae) from Humans of Mazandaran Province, Iran

  • Sharifdini, Meysam;Heidari, Zahra;Hesari, Zahra;Vatandoost, Sajad;Kia, Eshrat Beigom
    • Parasites, Hosts and Diseases
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    • v.55 no.3
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    • pp.279-285
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    • 2017
  • The present study was performed to analyze molecularly the phylogenetic positions of human-infecting Trichostrongylus species in Mazandaran Province, Iran, which is an endemic area for trichostrongyliasis. DNA from 7 Trichostrongylus infected stool samples were extracted by using in-house (IH) method. PCR amplification of ITS2-rDNA region was performed, and products were sequenced. Phylogenetic analysis of the nucleotide sequence data was performed using MEGA 5.0 software. Six out of 7 isolates had high similarity with Trichostrongylus colubriformis, while the other one showed high homology with Trichostrongylus axei registered in GenBank reference sequences. Intra-specific variations within isolates of T. colubriformis and T. axei amounted to 0-1.8% and 0-0.6%, respectively. Trichostrongylus species obtained in the present study were in a cluster with the relevant reference sequences from previous studies. BLAST analysis indicated that there was 100% homology among all 6 ITS2 sequences of T. colubriformis in the present study and most previously registered sequences of T. colubriformis from human, sheep, and goat isolates from Iran and also human isolates from Laos, Thailand, and France. The ITS2 sequence of T. axei exhibited 99.4% homology with the human isolate of T. axei from Thailand, sheep isolates from New Zealand and Iran, and cattle isolate from USA.

Mutation Detection of E6 and LCR Genes from HPV 16 Associated with Carcinogenesis

  • Mosmann, Jessica P.;Monetti, Marina S.;Frutos, Maria C.;Kiguen, Ana X.;Venezuela, Raul F.;Cuffini, Cecilia G.
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.3
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    • pp.1151-1157
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    • 2015
  • Human papillomavirus (HPV) is responsible for one of the most frequent sexually transmitted infections. The first phylogenetic analysis was based on a LCR region fragment. Nowadays, 4 variants are known: African (Af-1, Af-2), Asian-American (AA) and European (E). However the existence of sub-lineages of the European variant havs been proposed, specific mutations in the E6 and LCR sequences being possibly related to persistent viral infections. The aim of this study was a phylogenetic study of HPV16 sequences of endocervical samples from C${\acute{o}}$rdoba, in order to detect the circulating lineages and analyze the presence of mutations that could be correlated with malignant disease. The phylogenetic analysis determined that 86% of the samples belonged to the E variant, 7% to AF-1 and the remaining 7% to AF-2. The most frequent mutation in LCR sequences was G7521A, in 80% of the analyzed samples; it affects the binding site of a transcription factor that could contribute to carcinogenesis. In the E6 sequences, the most common mutation was T350G (L83V), detected in 67% of the samples, associated with increased risk of persistent infection. The high detection rate of the European lineage correlated with patterns of human migration. This study emphasizes the importance of recognizing circulating lineages, as well as the detection of mutations associated with high-grade neoplastic lesions that could be correlated to the development of carcinogenic lesions.

Sulzbacheromyces sinensis, an Unexpected Basidiolichen, was Newly Discovered from Korean Peninsula and Philippines, with a Phylogenetic Reconstruction of Genus Sulzbacheromyces

  • Liu, Dong;Wang, Xin Yu;Wang, Li Song;Maekawa, Nitaro;Hur, Jae-Seoun
    • Mycobiology
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    • v.47 no.2
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    • pp.191-199
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    • 2019
  • Most of lichens are formed by Ascomycota, less than 1% are lichenized Basidiomycota. The flora investigation of lichenized Ascomycota of South Korea has been well studied in the past three decades; however, prior to this study, none of basidiolichens was discovered. During the recent excursion, an unexpected clavarioid basidiolichen, Sulzbacheromyces sinensis was collected. Morphology and ecology has been recorded in detail. DNA was extracted, and ITS, 18S, 28S nuclear rDNA were generated. In order to further confirm the systematic position of the Korean specimens, maximum likelihood and Bayesian inference analysis including all the species of the order Lepidostromatales were conducted based on the ITS. As a result, the phylogenetic tree of the order Lepidostromatales was reconstructed, which differed from the previous studies. The inferred phylogenetic tree showed that species of Sulzbacheromyces in three different continents (Asia, South Africa and South America) were separated into three clades with support. In this study, the species worldwide distribution map of Lepidostromatales was illustrated, and S. sinensis had a widest distribution range (paleotropical extend to the Sino-Japanese) than other species (paleotropical or neotropical). Prior to this study, the range of distribution, southernmost and northernmost points and the fruiting time of S. sinensis were recorded, and the genus Sulzbacheromyces was firstly reported from Korean peninsula and Philippines.

Genetic Diversity and Phylogenetic Analysis of the Iranian Leishmania Parasites Based on HSP70 Gene PCR-RFLP and Sequence Analysis

  • Nemati, Sara;Fazaeli, Asghar;Hajjaran, Homa;Khamesipour, Ali;Anbaran, Mohsen Falahati;Bozorgomid, Arezoo;Zarei, Fatah
    • Parasites, Hosts and Diseases
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    • v.55 no.4
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    • pp.367-374
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    • 2017
  • Despite the broad distribution of leishmaniasis among Iranians and animals across the country, little is known about the genetic characteristics of the causative agents. Applying both HSP70 PCR-RFLP and sequence analyses, this study aimed to evaluate the genetic diversity and phylogenetic relationships among Leishmania spp. isolated from Iranian endemic foci and available reference strains. A total of 36 Leishmania isolates from almost all districts across the country were genetically analyzed for the HSP70 gene using both PCR-RFLP and sequence analysis. The original HSP70 gene sequences were aligned along with homologous Leishmania sequences retrieved from NCBI, and subjected to the phylogenetic analysis. Basic parameters of genetic diversity were also estimated. The HSP70 PCR-RFLP presented 3 different electrophoretic patterns, with no further intraspecific variation, corresponding to 3 Leishmania species available in the country, L. tropica, L. major, and L. infantum. Phylogenetic analyses presented 5 major clades, corresponding to 5 species complexes. Iranian lineages, including L. major, L. tropica, and L. infantum, were distributed among 3 complexes L. major, L. tropica, and L. donovani. However, within the L. major and L. donovani species complexes, the HSP70 phylogeny was not able to distinguish clearly between the L. major and L. turanica isolates, and between the L. infantum, L. donovani, and L. chagasi isolates, respectively. Our results indicated that both HSP70 PCR-RFLP and sequence analyses are medically applicable tools for identification of Leishmania species in Iranian patients. However, the reduced genetic diversity of the target gene makes it inevitable that its phylogeny only resolves the major groups, namely, the species complexes.

Study on Molecular Phylogenetics of Korean Arisaema Species Based on Universal DNA Barcodes (범용성 DNA 바코드 분석 기반 한국산 천남성속(Arisaema) 식물의 분자계통학적 연구)

  • Noh, Pureum;Han, Kyeongsuk;Kim, Wook Jin;Yang, Sungyu;Choi, Goya;Ko, Sung Chul;Moon, Byeong Cheol
    • Korean Journal of Plant Resources
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    • v.31 no.1
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    • pp.37-51
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    • 2018
  • Molecular phylogenetic analysis was conducted to evaluate the taxonomic relationships of genus Arisaema L. distributed in Korea and the molecular phylogenetic characteristics of three authentic Arisaema species for the herbal medicine Arisaematis Rhizoma (the rhizomes of A. amurense, A. heterophyllum, and A. erubescens). The sequences of three DNA barcodes (rDNA-ITS, matK, and rbcL) were analyzed using 50 samples of nine taxa consisted of eight Korean and one Chinese Arisaema with one outgroup (Dracunculus vulgaris). Both individual and combined phylogenetic analyses of three DNA barcode sequences revealed that the treated nine taxa are independently classified into six distinct clades (Clade I, A. amurense f. amurense and A. amurense f. serratum; Clade II, A. serratum and A. takesimense; Clade III, A. ringens; Clade IV, A. erubescens; Clade V, A. heterophyllum; Clade VI, A. thunbergii subsp. thunbergii and A. thunbergii subsp. geomundoense). These six clades were reasonably divided into three individual sections, Pedatisecta, Sinarisaema, and Tortuosa. Futhermore, the results of comparative DNA barcode sequences analyses provided a significant information for the taxonomic reconsideration of Arisaema L. at the specific and intraspecific level. However, we could not confirm the taxonomic characteristics or identity among the three authentic medicinal species through the molecular phylogenetic analyses of genus Arisaema L. for Arisaematis Rhizoma.