Jun-Gu Kang

New genetic variants of Anaplasma phagocytophilum and Anaplasma bovis from Korean water deer (Hydropotes inermis argyropus).

Wild deer are one of the important natural reservoir hosts of Anaplasma species, which cause granulocytic anaplasmosis in equines, canines, and humans. The objective of the present study was to determine whether and what species of Anaplasma naturally infect Korean water deer (KWD) in the Republic of Korea. A total of 66 spleens from KWD carcasses were collected by the Conservation Genome Resource Bank for Korean Wildlife in Korea between March 2008 and May 2009. Polymerase chain reaction (PCR) was performed using 16S ribosomal (r)RNA, with ankA, groEL, and msp2 gene primers to amplify the genes of Anaplasma and Ehrlichia. Using 16S rRNA-based nested PCR, Anaplasma phagocytophilum and Anaplasma bovis were detected in 42 (63.6%) and 23 (34.8%) of 66 KWD spleens, respectively. The 42 A. phagocytophilum were classified into five genotypes and the 23 A. bovis were classified into two genotypes by sequence analysis. By ankA-, groEL-, and msp2-based nested PCR, A. phagocytophilum was detected in 1 (1.5%), 7 (10.6%), and 3 (4.6%) of 66 samples, respectively. These gene sequences had only one genotype. Five of seven obtained 16S rRNA gene sequences have never been identified. The ankA, groEL, and msp2 obtained gene sequences represented new genotypes. This is the first report of A. phagocytophilum and A. bovis in KWD, suggesting that they may act as reservoirs for anaplasmosis zoonotic pathogens.

Isolation and characterization of equine amniotic fluid-derived multipotent stem cells.

BACKGROUND AIMSnAmniotic fluid (AF) is a well-known source of stem cells. However, there have been no reports regarding equine AF stem cells. We have isolated equine AF-derived multipotent stem cells (MSC) (eAF-MSC) and show that these cells exhibit self-renewal ability and multilineage differentiation.nnnMETHODSnAF was obtained from thoroughbred mares and mononuclear cells (MNC) were isolated by Ficoll-Paque density gradient. We measured the cumulative population doubling level (CPDL) and characterized the immunophenotype by flow cytometry. To investigate differentiation ability, a trilineage differentiation assay was conducted.nnnRESULTSneAF-MSC could be isolated and the proliferation level was high. eAF-MSC presented typical MSC phenotypic markers, as determined by flow cytometry. Moreover, eAF-MSC showed a trilineage differentiation capability.nnnCONCLUSIONSnEquine AF is a good source of MSC. Furthermore, eAF-MSC may be useful as a cell therapy application for horses.

Molecular Detection of Anaplasma, Bartonella, and Borrelia Species in Ticks Collected from Migratory Birds from Hong-do Island, Republic of Korea

Bird migration is a recurring annual and seasonal event undertaken by more than 100 species of birds in the southeast Asian and northeast Palearctic regions that pass through or remain for short periods from April to May and September to November at Hong-do Island, Republic of Korea (ROK). A total of 212 ticks (40 Haemaphysalis flava, 12 H. longicornis, 146 Ixodes turdus, 13 I. nipponensis, and 1 I. ornithophila) were collected from 65/2,161 (3.0%) migratory birds consisting of 21 species that were captured from January, 2008, through December, 2009, as part of the Migratory Birds Center, Hong-do bird banding program for studying bird migration patterns. Adult ticks were assayed individually while larvae and nymphs were pooled (1-22 and 1-6 ticks per pool, respectively) into 31 and 65 pools, respectively. Ticks were assayed for zoonotic pathogens by PCR using 16S rRNA, heat shock protein (groEL), and internal transcribed spacer (ITS) gene primers to amplify genera specific for Anapalsma, Bartonella, and Borrelia PCR amplicons. Using the 16S rRNA-based nested PCR, A. phagocytophilum (n=1) was detected in I. nipponensis collected from Zoothera sibirica and A. bovis (n=1) was detected in I. turdus collected from Emberiza chrysophrys. Borrelia turdi 16S rRNA genes (n=3) were detected in I. turdus and I. nipponensis collected from Turdus pallidus and Zoothera aurea. Borrelia spp. 16S rRNA genes (n=4) were detected in Ixodes ticks collected from Emberiza tristrami, T. pallidus, and Z. aurea. The Bartonella grahamii ITS gene (n=1) was detected by nested PCR assay in I. turdus collected from Z. aurea. These results provide insight into the potential role of migratory birds in the dispersal of ticks and associated tick-borne pathogens throughout their ranges in Asia.

Prevalence of tick-borne encephalitis virus in ticks from southern Korea

The prevalence of tick-borne encephalitis virus (TBEV) in southern Korea was determined by collecting ticks using tick drags. A total of 4,077 of 6,788 ticks collected were pooled (649 pools) according to collection site, species, and developmental stage and assayed for TBEV. The TBEV protein E and NS5 gene fragments were detected using RT-nested PCR in six pools of nymphs collected from Jeju Island (2,491 ticks). The minimum field detection rates for TBEV were 0.17% and 0.14% for Haemaphysalis longicornis and Haemayphysalis flava nymphs, respectively. The 252 bp NS5 and 477 bp protein E gene amplicons were sequenced. Phylogenetic analysis showed that the NS5 and protein E genes of the Jeju strain were clustered with Western subtype (98.0% and 99.4% identity, respectively). The Western subtype of TBEV is endemic in Korea, including Jeju Island. The study of vector and zoonotic host susceptibility to TBEV is required to better understand its potential impact on public health.

Ticks Collected from Selected Mammalian Hosts Surveyed in the Republic of Korea During 2008-2009

A tick survey was conducted to determine the relative abundance and distribution of ticks associated with selected mammals in the Republic of Korea (ROK) during 2008-2009. A total of 918 ticks were collected from 76 mammals (6 families, 9 species) captured at 6 provinces and 3 Metropolitan Cities in ROK. Haemaphysalis longicornis (54.4%) was the most frequently collected tick, followed by Haemaphysalis flava (28.5%), Ixodes nipponensis (7.6%), Ixodes pomerantzevi (4.8%), Ixodes persulcatus (4.6%), and Haemaphysalis japonica (0.1%). Adults (57.0%) and nymphs (28.7%) of Ixodes and Haemaphysalis spp. were collected most frequently from medium or large mammals in this survey, while few larvae (14.3%) were collected. Hydropotes inermis was the most frequently captured mammal (52.6%), with a 16.4 tick index and 5 of 6 species of ticks collected during this survey. H. longicornis (69.7%) was the predominant tick collected from H. inermis, followed by H. flava (22.2%), I. persulcatus (6.1%), I. nipponensis (1.8%), and H. japonica (0.2%).

Characterization and clinical application of mesenchymal stem cells from equine umbilical cord blood.

Tendinitis of the superficial digital flexor tendon (SDFT) is a significant cause of lameness in horses; however, recent studies have shown that stem cells could be useful in veterinary regenerative medicine. Therefore, we isolated and characterized equine umbilical cord blood mesenchymal stem cells (eUCB-MSCs) from equine umbilical cord blood obtained from thoroughbred mares during the foaling period. Horses that had tendinitis of the SDFT were treated with eUCB-MSCs to confirm the therapeutic effect. After eUCB-MSCs transplantation, the core lesion in the SDFT was found to decrease. These results suggest that transplantation using eUCB-MSCs could be another source of cell treatment.

X‐ray photoemission studies of W 4f core levels of electrochromic HxWO3 films

Using x‐ray photoelectron spectroscopy (XPS), W 4f core level spectra of electrochromic HxWO3 films have been investigated as a function of the injected charge. W 4f peaks become broader with increasing injected charge. The line shape analysis of W 4f XPS spectra of amorphous HxWO3 films reveals that each spin‐orbit split component consists of two peaks. It is also found that, as the injected charge increases, the intensity of the low binding energy (BE) peaks, the asymmetry factor of core lines, and the intrinsic lifetime width increase systematically. Composite structures of W 4f peaks have been attributed to the existence of the different final states, screened by different numbers of W 5d electrons. The low BE peaks are considered to correspond to the locally screened final states, with one more W 5d electrons than in the ground state, which arise from midgap state conduction electrons near EF. There is also a possibility that a mixture of fine scale phases contributes to composite structures and broa...

Valence band and Sb 4d core level photoemission of the XMnSb-type Heusler compounds (X=Pt,Pd,Ni)

Electronic structures of the valence band and Sb 4d core levels of the XMnSb-type Heusler alloys (where X=Pt,Pd,Ni) have been investigated systematically using photoemission spectroscopy (PES) and self-consistent spin-polarized band structure calculations. The extracted Mn 3d PSW of XMnSb (where X=Pt, Pd) are found to be almost identical. Interestingly, they are quite different from those of Mn metal, but are analogous to those of MnO, suggesting that the role of the Sb 5p electrons in XMnSb may be similar to that of the O 2p electrons in MnO. A comparison of the PSW with the corresponding theoretical angular momentum projected density of states (PLDOS) shows a fairly good agreement for the Pt and Pd d states, but large discrepancies for the Mn and Ni 3d states. The calculated X d and Mn 3d PLDOS reveal that the hybridization between the Mn 3d and X d states increases from X=Pt to Pd and Ni. In the Sb 4d core level PES spectra, a broader and less structureless line shape is observed for X=Pd than for X=Pt and Ni. A detailed analysis of their line shapes indicates that it is due to a larger lifetime broadening for X=Pd than for X=Pt and Ni.

Photoemission, soft x-ray absorption, and magnetic circular dichroism spectroscopy study of Fe1−xCuxCr2S4 (0.1≤x≤0.5) spinel sulfides

The electronic and magnetic structures of Fe1−xCuxCr2S4 (0.1≤x≤0.5) spinel sulfides have been investigated systematically by performing photoemission spectroscopy (PES), soft x-ray absorption spectroscopy (XAS), and soft x-ray magnetic circular dichroism (XMCD) measurements using synchrotron radiation. Cr and Cu ions are found to be nearly trivalent (Cr3+) and monovalent (Cu+), respectively, and their valence states do not change with x. The Fe 2p XAS spectra of Fe1−xCuxCr2S4 are very similar to that of Fe metal, indicating that the Fe 3d electrons are strongly hybridized to other valence electrons. The Fe and Cr 2p XMCD spectra show that the magnetic moments of Cr ions and Fe ions are aligned antiparallel to each other and that both the Cr and Fe magnetic moments increase with increasing x. The valence-band PES study reveals that the Cr3+ () 3d states are located at ~1.5 eV below EF. The occupied Fe 3d states consist of the broad states, the states at ~4 eV below EF, and the states very close to EF. The filled Cu 3d10 states lie at ~2.5 eV below EF. This study suggests that the hybridized Fe and S 3p states near EF play an important role in determining the transport properties of Fe1−xCuxCr2S4 for x≤0.5.

Molecular Detection of Bartonella grahamii and B. schoenbuchensis-Related Species in Korean Water Deer (Hydropotes inermis argyropus)

We determined the prevalence of Bartonella spp. and investigated which species of Bartonella naturally infects Korean water deer (KWD, Hydropotes inermis argyropus) in the Republic of Korea (ROK). A total of 70 spleens from KWD carcasses were collected by the Conservation Genome Resource Bank for Korean Wildlife (CGRB) in the ROK between 2008 and 2009. Nested PCRs were performed using the rpoB gene and internal transcribed spacer (ITS) region primers to amplify the DNA fragment of Bartonella. Using ITS-based nested PCR, Bartonella grahamii and Bartonella schoenbuchensis-related species were detected in 11 (15.8%) and 9 (12.9%) of 70 KWD spleens, respectively. The 11 B. grahamii amplicons were classified into 2 genotypes by sequence analysis. Using rpoB-based nested PCR, B. grahamii was detected in 5 (7.1%) of 70 KWD spleen samples. This is the first report of B. grahamii and B. schoenbuchensis in KWD, suggesting that KWD may act as reservoirs for the spreading of Bartonella spp. in the ROK.