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To test whether the internal transcribed spacer 2 (ITS2) region is an effective marker for using in authenticating of the Schisandra chinensis at the species and population levels, separately. And the results showed that the wild populations had higher percentage of individuals that had substitution of C→A at site 86-bp than the cultivated populations. At sites 10-bp, 37-bp, 42-bp and 235-bp, these bases of the Schisandra sphenanthera samples differed from that of S. chinensis. Two species showed higher levels of inter-specific divergence than intra-specific divergence within ITS2 sequences. However, 24 populations did not demonstrate much difference as inter-specific and intra-specific divergences were concerned. Both S. chinensis and S. sphenanthera showed monophyly at species level, yet the samples of different populations shown polyphyly at population level. ITS2 performed well when using BLAST1 method. ITS2 obtained 100% identification success rates at the species level for S. chinensis, with no ambiguous identification at the genus level for ITS2 alone. The ITS2 region could be used to identify S. chinensis and S. sphenanthera in the “Chinese Pharmacopoeia”. And it could also correctly distinguish 100% of species and 100% of genera from the 193 sequences of S. chinensis. Hence, the ITS2 is a powerful and efficient tool for species identification of S. chinensis.
Two tapeworm specimens collected in northeast China in 2009 and 2011 were identified as Diphyllobothrium latum based on morphological criteria. Molecular methods were used to confirm their identity and analyze genetic variations compared with published data for this species. Species identity was confirmed by molecular characterization of the 18S rDNA partial sequence, complete sequences of internal transcribed spacers (ITSs) and 5.8S rDNA, and partial sequences of mitochondrial cytochrome c oxidase subunit 1 (cox1) and mitochondrial NADH dehydrogenase subunit 5 (nad5). PCR amplification and sequence analysis of 18S rDNA (1472 bp), ITS regions (1218 bp), cox1 (885 bp), and nad5 (1028 bp) revealed that these four sequences showed more than 99% identity to reference sequences for D. latum, confirming that this species is D. latum. To date, a total of 12 diphyllobothriosis cases have been documented in China. This study represents the first molecular characterization of D. latum in China, providing molecular evidence of human diphyllobothriosis in China.
Seven species of Cylicocyclus Ihle, 1922 (Nematoda: Strongylidae) were collected from donkeys from Henan Province, China. Five samples of each species were selected for sequencing. Sixteen different internal transcribed spacer (ITS) sequences representing the seven species of Cylicocyclus were obtained. Sequence differences in the first internal transcribed spacer (ITS-1) among species was lower than that of the second internal transcribed spacer (ITS-2). Phylogenetic analyses were conducted using the combined ITS-1 and ITS-2 data sets from the present study and using reference sequences from the GenBank database. The MP and ML trees were similar in topology. The phylogenetic trees were divided into two clades. Clade I included 8 species of Cylicocyclus; within this group, Cylicocyclus leptostomus (Kotlan, 1920) is nested between different samples of Cylicocyclus ashworthi (LeRoux, 1924), suggesting C. ashworthi may represent a species complex. Clade II included Cylicocyclus elongatus (Looss, 1900) and Cylicocyclus ultrajectinus (Ihle, 1920); however, these two species always clustered with the comparative species (Petrovinema poculatum (Looss, 1900) and Poteriostomum imparidentatum Quiel, 1919), suggesting that C. elongatus and C. ultrajectinus represent members of other genera.
In this study, two pairs of oligonucleotide primers were designed according to the nucleotide sequence of the internal transcribed spacers (ITSs) of Babesia bigemina and B. bovis isolates from China. The primers were used in a multiplex PCR to detect parasite DNA in blood samples from cattle. There was no cross reactions with B. ovata, B. major, B. sp. Kashi, Theileria annulata, T. sergenti, T. sinensis or normal bovine DNA. The sensitivity of multiplex PCR assay was 1 pg and 10 pg DNA for B. bigemina and B. bovis, respectively. A total of 260 field blood samples collected from cattle in five provinces of China were analyzed by multiplex PCR and light microscopy. PCR testing revealed that 7.3% (19/260) and 5.8% (15/260) of cattle were positive for B. bigemina and B. bovis and 1.2% (3/260) of cattle were co-infected with B. bigemina and B. bovis. Using light microscopy, 2.3% (6/260) and 1.5% (4/260) of cattle were infected by B. bigemina and B. bovis, respectively, and no co-infection was found. The results showed that the multiplex PCR developed in the present study could be an alternative diagnostic tool for the detection of B. bovis and B. bigemina infection in cattle.
Separate and combined analyses of nuclear ribosomal DNA internal transcribed spacer (ITS) and cpDNA rpsl6 provided phylogenetic hypotheses and molecular data for the taxonomy of Chinese Bupleurum species. The phylogenetic results derived from Bayesian and maximum parsimony analyses supported the monophyly of the Bupleurum with strong evidence. The origin of Chinese Bupleurum is likely to be through the Middle East and the Caucasus from the Mediterranean region with the basic chromosome number (8->7->6), and polyploidization. Our molecular data are not consistent with other earlier Chinese Bupleurum classifications and are consistent with the molecular classification proposed by Neves and Watson. The analyses also provide molecular data to elucidate the taxonomic treatments for Bupleurum falcatum from China and Europe.
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