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For several years, we have conducted a series of studies on the patterns of ancient parasitism prevailing in the soil of rural and urban areas of past Kingdom of Korea. Actually, during our survey of paleoparasitology in archaeological sites of Korean peninsula, numerous ancient parasite eggs were discovered in the samples from the city districts of Hansung (Joseon) and Buyeo (Baikje), the palace moat at Gyeongju (Silla), shell-midden site at Bonghwang-dong (Silla to Joseon), and the reservoir found in Hwawangsansung fortress (Silla). By the paleoparasitological studies, with respect to parasitism in the high-density populations of ancient towns and cities, we have managed to catch glimpses of the patterns prevalent therein: a serious parasitic contamination of the soil in ancient urban areas, but not in rural areas of the past. Our historical research also proposed the plausible mechanism of parasite infection very serious indeed among urban populations in Korean history. Although city dwelling doubtless has accrued significant benefits for people and populations with agriculture, it can be equally supposed that living in such highly populated areas might have facilitated the spread of parasite infection.  相似文献   
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This study aimed to develop a multiplex-touchdown PCR method to simultaneously detect 3 species of protozoan parasites, i.e., Cryptosporidium parvum, Giardia lamblia, and Cyclospora cayetanensis, the major causes of traveler’s diarrhea and are resistant to standard antimicrobial treatments. The target genes included the Cryptosporidium oocyst wall protein for C. parvum, Glutamate dehydrogenase for G. lamblia, and 18S ribosomal RNA (18S rRNA) for C. cayetanensis. The sizes of the amplified fragments were 555, 188, and 400 bps, respectively. The multiplex-touchdown PCR protocol using a primer mixture simultaneously detected protozoa in human stools, and the amplified gene was detected in >1×103 oocysts for C. parvum, >1×104 cysts for G. lamblia, and >1 copy of the 18S rRNA gene for C. cayetanensis. Taken together, our protocol convincingly demonstrated the ability to simultaneously detect C. parvum, G. lamblia, and C. cayetanenesis in stool samples.  相似文献   
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The mitochondrial genome (mitogenome) can provide important information for understanding molecular evolution and phylogenetic analyses. The complete mitogenome of Spodoptera frugiperda (Lepidoptera:Noctuidae) was determined to be 15,365 bp in length and has the typical gene order found in Noctuidae mitogenomes, it includes 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes and a A+T-rich region. The nucleotide composition was biased toward A+T nucleotides (81.09 %) and the AT skew of this mitogenome was slightly positive (0.004). All PCGs were initiated by ATN codons, except for cytochrome c oxidase subunit 1 (cox1) gene which was initiated by CGA. Eight of the 13 PCGs have the incomplete termination codon, T or TA. All the tRNA genes displayed the typical clover-leaf structure of mitochondrial tRNAs, with the exception of trnS1 (AGN). The A+T-rich region was 328 bp in length and consisted of several features common to the Noctuidae insects. Phylogenetic analysis showed that the S. frugiperda was within the Noctuidae.  相似文献   
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We performed a systematic review of genome‐wide gene expression datasets to identify key genes and functional modules involved in the pathogenesis of systemic lupus erythematosus (SLE) at a systems level. Genome‐wide gene expression datasets involving SLE patients were searched in Gene Expression Omnibus and ArrayExpress databases. Robust rank aggregation (RRA) analysis was used to integrate those public datasets and identify key genes associated with SLE. The weighted gene coexpression network analysis (WGCNA) was adapted to identify functional modules involved in SLE pathogenesis, and the gene ontology enrichment analysis was utilized to explore their functions. The aberrant expressions of several randomly selected key genes were further validated in SLE patients through quantitative real‐time polymerase chain reaction. Fifteen genome‐wide gene expression datasets were finally included, which involved a total of 1,778 SLE patients and 408 healthy controls. A large number of significantly upregulated or downregulated genes were identified through RRA analysis, and some of those genes were novel SLE gene signatures and their molecular roles in etiology of SLE remained vague. WGCNA further successfully identified six main functional modules involved in the pathogenesis of SLE. The most important functional module involved in SLE included 182 genes and mainly enriched in biological processes, including defense response to virus, interferon signaling pathway, and cytokine‐mediated signaling pathway. This study identifies a number of key genes and functional coexpression modules involved in SLE, which provides deepening insights into the molecular mechanism of SLE at a systems level and also provides some promising therapeutic targets.  相似文献   
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