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Spider bites cause a range of symptoms from simple swellings to disfiguring necrotic lesions, and occasionally death. While spider bites are not a major medical problem in Korea, it would be of great value to know which species of spiders pose a threat to human health. A middle molecular weight protein, sphingomyelinase D, has been identified in the venom of the brown recluse spider and strong evidence suggests that they have a major role in spider bite necrosis. For the identification of necrotizing species, we have investigated using recently developed non‐radioactive assay of sphingomyelinase for rapidly screening the necrotizing venoms. Here, we demonstrate the fetal toxicity of total 65 species (24 genera, 9 families) of the web‐building spiders among 622 identified spider species in Korea. It has been revealed that four species of the orb‐weaving spider, Araneus ventricosus (family Araneidae, 0.3509), Dipoena castrata (0.2413, family Theridiidae), Argiope minuta (0.1836, family Araneidae), and Paracoelotes spinivulva (0.1760, family Amaurobiidae) have relatively strong activities among themselves. However, comparing to that of the brown recluse spider, Loxosceles recluse (1.814) in North America, the necrotizing shpingomyelinase activities of these Korean web‐building spiders are still very low. Based on our results, we may thus conclude that there would be little possibilities in South Korea to create serious medical problems caused by necrotizing arachnidism.  相似文献   
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To identify putative biomarkers of porcine spermatogonial stem cells (pSSCs), total RNA sequencing (RNA-seq) analysis was performed on 5- and 180-day-old porcine testes and on pSSC colonies that were established under low temperature culture conditions as reported previously. In total, 10,184 genes were selected using Cufflink software, followed by a logarithm and quantile normalization of the pairwise scatter plot. The correlation rates of pSSCs compared to 5- and 180-day-old testes were 0.869 and 0.529, respectively and that between 5- and 180-day-old testes was 0.580. Hierarchical clustering data revealed that gene expression patterns of pSSCs were similar to 5-day-old testis. By applying a differential expression filter of four fold or greater, 607 genes were identified between pSSCs and 5-day-old testis, and 2118 genes were identified between the 5- and 180-day-old testes. Among these differentially expressed genes, 293 genes were upregulated and 314 genes were downregulated in the 5-day-old testis compared to pSSCs, and 1106 genes were upregulated and 1012 genes were downregulated in the 180-day-old testis compared to the 5-day-old testis. The following genes upregulated in pSSCs compared to 5-day-old testes were selected for additional analysis: matrix metallopeptidase 9 (MMP9), matrix metallopeptidase 1 (MMP1), glutathione peroxidase 1 (GPX1), chemokine receptor 1 (CCR1), insulin-like growth factor binding protein 3 (IGFBP3), CD14, CD209, and Kruppel-like factor 9 (KLF9). Expression levels of these genes were evaluated in pSSCs and in 5- and 180-day-old porcine testes. In addition, immunohistochemistry analysis confirmed their germ cell-specific expression in 5- and 180-day-old testes. These finding may not only be useful in facilitating the enrichment and sorting of porcine spermatogonia, but may also be useful in the study of the early stages of spermatogenic meiosis.  相似文献   
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The genus Cidaria Treitschke is revised. Eight species of the genus which occur widely in the Palaearctic and northern India, are recognized, of which one, Cidaria luteata sp. nov. , is described as new while two subspecies of C. fulvata (Forster) are elevated to species, C. nugata Felder stat. rev., and C. distinctata Staudinger stat. nov. C. ochripennis Prout is proposed as a junior synonym of C. ochreata Staudinger. C. deletaria Hampson is excluded from the genus. All species of Cidaria and their genitalia are described and illustrated. The cladistic analysis of these eight species of Cidaria is carried out using two data matrices, the first comprising morphological characters alone and the second morphological and distributional characters. The most parsimonious cladogram of Cidaria is selected, and its monophyly defined. The character analysis shows that some distribution characters contribute to resolving the in group node. The choice of multiple trees is discussed.  相似文献   
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Helicobacter pylori is a causative agent of gastritis and peptic ulceration in humans. As the first step towards development of a vaccine against H. pylori infection, we have attempted to identify protective antigens. A potential target of vaccine development would be a H. pylori specific protein, which is surface-exposed and highly antigenic. We identified a 22 kDa outer-membrane protein (Omp22) from H. pylori, which was highly immunoreactive. By screening a H. pylori genomic DNA library with rabbit anti-H. pylori outer-membrane protein antibodies, the omp22 gene was cloned and 1.4 kb of the nucleotide sequence was determined. One open reading frame, encoding a 179-residue polypeptide, was identified and the amino acid sequence deduced showed homology with peptidoglycan-associated lipoproteins. The sequence was conserved among other H. pylori strains. Omp22 protein is expressed as a precursor polypeptide of 179 residues and undergoes lipid modification and cleavage of an 18 amino acid signal peptide to yield a mature protein. Omp22 protein in H. pylori as well as recombinant Omp22 protein expressed in E. coli was localized into the outer membrane and exposed on the cell surface. Omp22 may have the potential as a target antigen for the development of a H. pylori vaccine.  相似文献   
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ABSTRACT Among forty species of the Korean Cidariini, a tribe of Larentiinae (Lepidoptera, Geometridae), nineteen species of ten genera are revised: Ecliptopera Warren, Lampropteryx Stephens, Eustroma Hübner, Eveeliptopera Inoue, Lobogonodes Bastelberger, Hysterura Warren, Sibatania Inoue, Eulithis Hiibner, Gandaritis Moore, and Electrophaes Prout. The diagnostic characters and monophyly of each genus are provided. Figures of adults including male and female genitalia, and distribution maps in Korea are also provided.  相似文献   
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A cladistic biogeographic analysis for the Holarctic and Indo-Chinese regions was undertaken based on seven genera of the tribe Cidariini: Cidaria Treitschke, Thera Stephens, Pennithera Viidalepp, Heterothera Inoue, Callabraxas Butler, Gandaritis Moore and Eulithis Httbner. Smallest coincident ranges of two species recognized 11 endemic areas. The study has two aims: to construct a hierarchical structure of those areas, and to recognize dispersal events. Under two assumptions [widespread taxa mapped (identical as assumption 0) and widespread taxa not mapped (identical as assumption 1)] the 11 endemic areas were mapped with 72 taxa. The best resolved area cladograms under the two assumptions differ in the placement of one endemic area, northern Europe. Area relationships found in this present analysis are congruent with the current landmass configurations: (North America, (Europe, (northern India, (southwestern Asia, (Baikal area, (south China, (Taiwan, (Russian Far East, Japan)))))))). These area cladograms postulate at least three vicariance events: (1) between North America and the Palaearctic; (2) western-eastern Palaearctic; (3) northern India–the rest of Asia. The approach to recognize dispersed taxa by pruning each taxon suggests that most dispersal events occurred in East Asia: from the Baikal area or south China to the Russian Far East; and from the Russian Far East to Japan. Relationships among endemic areas are briefly discussed.  相似文献   
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