A waterborne outbreak and detection of cryptosporidium oocysts in drinking water of an older high-rise apartment complex in seoul.

From May to June 2012, a waterborne outbreak of 124 cases of cryptosporidiosis occurred in the plumbing systems of an older high-rise apartment complex in Seoul, Republic of Korea. The residents of this apartment complex had symptoms of watery diarrhea and vomiting. Tap water samples in the apartment complex and its adjacent buildings were collected and tested for 57 parameters under the Korean Drinking Water Standards and for additional 11 microbiological parameters. The microbiological parameters included total colony counts, Clostridium perfringens, Enterococcus, fecal streptococcus, Salmonella, Shigella, Pseudomonas aeruginosa, Cryptosporidium oocysts, Giardia cysts, total culturable viruses, and Norovirus. While the tap water samples of the adjacent buildings complied with the Korean Drinking Water Standards for all parameters, fecal bacteria and Cryptosporidium oocysts were detected in the tap water samples of the outbreak apartment complex. It turned out that the agent of the disease was Cryptosporidium parvum. The drinking water was polluted with sewage from a septic tank in the apartment complex. To remove C. parvum oocysts, we conducted physical processes of cleaning the water storage tanks, flushing the indoor pipes, and replacing old pipes with new ones. Finally we restored the clean drinking water to the apartment complex after identification of no oocysts.

Evolution of the Araliaceae family involved rapid diversification of the Asian Palmate group and Hydrocotyle specific mutational pressure.

The Araliaceae contain many valuable species in medicinal and industrial aspects. We performed intensive phylogenomics using the plastid genome (plastome) and 45S nuclear ribosomal DNA sequences. A total of 66 plastome sequences were used, 13 of which were newly assembled in this study, 12 from new sequences, and one from existing data. While Araliaceae plastomes showed conserved genome structure, phylogenetic reconstructions based on four different plastome datasets revealed phylogenetic discordance within the Asian Palmate group. The divergence time estimation revealed that splits in two Araliaceae subfamilies and the clades exhibiting phylogenetic discordances in the Asian Palmate group occurred at two climatic optima, suggesting that global warming events triggered species divergence, particularly the rapid diversification of the Asian Palmate group during the Middle Miocene. Nucleotide substitution analyses indicated that the Hydrocotyloideae plastomes have undergone accelerated AT-biased mutations (C-to-T transitions) compared with the Aralioideae plastomes, and the acceleration may occur in their mitochondrial and nuclear genomes as well. This implies that members of the genus Hydrocotyle, the only aquatic plants in the Araliaceae, have experienced a distinct evolutionary history from the other species. We also discussed the intercontinental disjunction in the genus Panax and proposed a hypothesis to complement the previously proposed hypothesis. Our results provide the evolutionary trajectory of Araliaceae and advance our current understanding of the evolution of Araliaceae species.

High-throughput discovery of plastid genes causing albino phenotypes in ornamental chimeric plants.

Chimeric plants composed of green and albino tissues have great ornamental value. To unveil the functional genes responsible for albino phenotypes in chimeric plants, we inspected the complete plastid genomes (plastomes) in green and albino leaf tissues from 23 ornamental chimeric plants belonging to 20 species, including monocots, dicots, and gymnosperms. In nine chimeric plants, plastomes were identical between green and albino tissues. Meanwhile, another 14 chimeric plants were heteroplasmic, showing a mutation between green and albino tissues. We identified 14 different point mutations in eight functional plastid genes related to plastid-encoded RNA polymerase (rpo) or photosystems which caused albinism in the chimeric plants. Among them, 12 were deleterious mutations in the target genes, in which early termination appeared due to small deletion-mediated frameshift or single nucleotide substitution. Another was single nucleotide substitution in an intron of the ycf3 and the other was a missense mutation in coding region of the rpoC2 gene. We inspected chlorophyll structure, protein functional model of the rpoC2, and expression levels of the related genes in green and albino tissues of Reynoutria japonica. A single amino acid change, histidine-to-proline substitution, in the rpoC2 protein may destabilize the peripheral helix of plastid-encoded RNA polymerase, impairing the biosynthesis of the photosynthesis system in the albino tissue of R. japonica chimera plant.

Analysis of the complete plastomes and nuclear ribosomal DNAs from Euonymus hamiltonianus and its relatives sheds light on their diversity and evolution.

Euonymus hamiltonianus and its relatives (Celastraceae family) are used for ornamental and medicinal purposes. However, species identification in Euonymus is difficult due to their morphological diversity. Using plastid genome (plastome) data, we attempt to reveal phylogenetic relationship among Euonymus species and develop useful markers for molecular identification. We assembled the plastome and nuclear ribosomal DNA (nrDNA) sequences from five Euonymus lines collected from South Korea: three Euonymus hamiltonianus accessions, E. europaeus, and E. japonicus. We conducted an in-depth comparative analysis using ten plastomes, including other publicly available plastome data for this genus. The genome structures, gene contents, and gene orders were similar in all Euonymus plastomes in this study. Analysis of nucleotide diversity revealed six divergence hotspots in their plastomes. We identified 339 single nucleotide polymorphisms and 293 insertion or deletions among the four E. hamiltonianus plastomes, pointing to abundant diversity even within the same species. Among 77 commonly shared genes, 9 and 33 were identified as conserved genes in the genus Euonymus and E. hamiltonianus, respectively. Phylogenetic analysis based on plastome and nrDNA sequences revealed the overall consensus and relationships between plastomes and nrDNAs. Finally, we developed six barcoding markers and successfully applied them to 31 E. hamiltonianus lines collected from South Korea. Our findings provide the molecular basis for the classification and molecular taxonomic criteria for the genus Euonymus (at least in Korea), which should aid in more objective classification within this genus. Moreover, the newly developed markers will be useful for understanding the species delimitation of E. hamiltonianus and closely related species.

Diversity and authentication of Rubus accessions revealed by complete plastid genome and rDNA sequences.

Complete plastid genome (plastome) and ribosomal DNA (rDNA) sequences of three Rubus accessions (two Rubus longisepalus and one R. hirsutus) were newly assembled using Illumina whole-genome sequences. Rubus longisepalus Nakai and R. longisepalus var. tozawai, described as different varieties, have identical plastomes and rDNA sequences. The plastomes are 155,957 bp and 156,005 bp and the 45S rDNA transcription unit sizes are 5809 bp and 5811 bp in R. longisepalus and R. hirsutus, respectively. The 5S rDNA transcription unit is an identical 121 bp in three Rubus accessions. We developed three DNA markers to authenticate R. longisepalus and R. hirsutus based on plastome diversity. Phylogenomic analysis revealed that the Rubus species classified as two clades and R. longisepalus, R. hirsutus, and R. chingii are the most closely related species in clade 1.

Immediate implant placement and provisionalization--two case reports.

Endosseous dental implants have traditionally been placed using a two-stage surgical procedure with a 6- to 12-month healing period following tooth extraction. In order to decrease healing time, protocols were introduced that included immediate implant placement and provisionalization following tooth extraction. Although survival rates for this technique are high, postoperative gingival shrinkage and bone resorption in the aesthetic zone are potential limitations. The two case reports described herein present a surgical technique for the preservation of anterior aesthetics that combines minimally invasive extraction, immediate implant placement, provisionalization, and the use of implants with a laser micro-grooved coronal design.

Indium mediated allylation of quinoline and isoquinoline activated by phenyl chloroformate.

Quinoline and isoquinoline activated by phenyl chloroformate were allylated using indium and allyl bromides in THF at room temperature to give the corresponding allyldihydroquinoline and allyldihydroisoquinoline in good to high yields.