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51.
S.-J. Heo K. Tatebayashi J. Kato H. Ikeda 《Molecular genetics and genomics : MGG》1998,257(2):149-156
The Saccharomyces cerevisiae gene RHC21 is a homologue of the fission yeast rad21 +gene, which affects the sensitivity of cells to γ-irradiation and is essential for cell growth in S. pombe. Disruption of the RHC21 gene showed that it is also essential in S. cerevisiae. To examine its function in cell growth further, we have isolated temperature-sensitive mutants for the RHC21 gene and characterized one of them, termed rhc21-sk16. When this mutant was incubated at 36°?C, the percentage of large-budded cells was increased. Most of the large-budded cells had aberrant nuclear structures, such as unequally extended nuclear DNA with incompletely elongated spindles across the mother-daughter neck or only in a mother cell. Furthermore, a circular minichromosome is more unstable in the mutant than in the wild-type, even at 25°?C. Flow cytometry showed that the bulk of DNA replication takes place normally at the restrictive temperature in the mutant. These results indicated that the RHC21 gene is required for proper segregation of the chromosomes. In addition, we found that the mutant is sensitive not only to UV radiation and γ-rays but also to the antimicrotubule agent nocodazole at 25°?C. This suggests that the RHC21 gene is involved in the microtubule function. We discuss how the RHC21 gene product may be involved in chromosome segregation and microtubule function. 相似文献
52.
53.
Sangbin Han Jong Hwan Lee Gaabsoo Kim Justin Sangwook Ko Soo Joo Choi Ji Hae Kwon Burn Young Heo Mi Sook Gwak 《PloS one》2015,10(5)
BackgroundThermodilution technique using a pulmonary artery catheter is widely used for the assessment of cardiac output (CO) in patients undergoing liver transplantation. However, the unclearness of the risk-benefit ratio of this method has led to an interest in less invasive modalities. Thus, we evaluated whether noninvasive bioreactance CO monitoring is interchangeable with thermodilution technique.MethodsNineteen recipients undergoing adult-to-adult living donor liver transplantation were enrolled in this prospective observational study. COs were recorded automatically by the two devices and compared simultaneously at 3-minute intervals. The Bland–Altman plot was used to evaluate the agreement between bioreactance and thermodilution. Clinically acceptable agreement was defined as a percentage error of limits of agreement <30%. The four quadrant plot was used to evaluate concordance between bioreactance and thermodilution. Clinically acceptable concordance was defined as a concordance rate >92%.ResultsA total of 2640 datasets were collected. The mean CO difference between the two techniques was 0.9 l/min, and the 95% limits of agreement were -3.5 l/min and 5.4 l/min with a percentage error of 53.9%. The percentage errors in the dissection, anhepatic, and reperfusion phase were 50.6%, 56.1%, and 53.5%, respectively. The concordance rate between the two techniques was 54.8%.ConclusionBioreactance and thermodilution failed to show acceptable interchangeability in terms of both estimating CO and tracking CO changes in patients undergoing liver transplantation. Thus, the use of bioreactance as an alternative CO monitoring to thermodilution, in spite of its noninvasiveness, would be hard to recommend in these surgical patients. 相似文献
54.
Gi Byoung Hwang Ki Joon Heo Ji Ho Yun Jung Eun Lee Hee Ju Lee Chu Won Nho Gwi- Nam Bae Jae Hee Jung 《PloS one》2015,10(5)
Controlling bioaerosols has become more important with increasing participation in indoor activities. Treatments using natural-product nanomaterials are a promising technique because of their relatively low toxicity compared to inorganic nanomaterials such as silver nanoparticles or carbon nanotubes. In this study, antimicrobial filters were fabricated from natural Euscaphis japonica nanoparticles, which were produced by nebulizing E. japonica extract. The coated filters were assessed in terms of pressure drop, antimicrobial activity, filtration efficiency, major chemical components, and cytotoxicity. Pressure drop and antimicrobial activity increased as a function of nanoparticle deposition time (590, 855, and 1150 µg/cm2filter at 3-, 6-, and 9-min depositions, respectively). In filter tests, the antimicrobial efficacy was greater against Staphylococcus epidermidis than Micrococcus luteus; ~61, ~73, and ~82% of M. luteus cells were inactivated on filters that had been coated for 3, 6, and 9 min, respectively, while the corresponding values were ~78, ~88, and ~94% with S. epidermidis. Although statistically significant differences in filtration performance were not observed between samples as a function of deposition time, the average filtration efficacy was slightly higher for S. epidermidis aerosols (~97%) than for M. luteus aerosols (~95%). High-performance liquid chromatography (HPLC) and electrospray ionization-tandem mass spectrometry (ESI/MS) analyses confirmed that the major chemical compounds in the E. japonica extract were 1(ß)-O-galloyl pedunculagin, quercetin-3-O-glucuronide, and kaempferol-3-O-glucoside. In vitro cytotoxicity and disk diffusion tests showed that E. japonica nanoparticles were less toxic and exhibited stronger antimicrobial activity toward some bacterial strains than a reference soluble nickel compound, which is classified as a human carcinogen. This study provides valuable information for the development of a bioaerosol control system that is environmental friendly and suitable for use in indoor environments. 相似文献
55.
Seung Yeon Shin Soochahn Lee Il Dong Yun Ho Yub Jung Yong Seok Heo Sun Mi Kim Kyoung Mu Lee 《PloS one》2015,10(12)
In this paper, we present a novel cascaded classification framework for automatic detection of individual and clusters of microcalcifications (μC). Our framework comprises three classification stages: i) a random forest (RF) classifier for simple features capturing the second order local structure of individual μCs, where non-μC pixels in the target mammogram are efficiently eliminated; ii) a more complex discriminative restricted Boltzmann machine (DRBM) classifier for μC candidates determined in the RF stage, which automatically learns the detailed morphology of μC appearances for improved discriminative power; and iii) a detector to detect clusters of μCs from the individual μC detection results, using two different criteria. From the two-stage RF-DRBM classifier, we are able to distinguish μCs using explicitly computed features, as well as learn implicit features that are able to further discriminate between confusing cases. Experimental evaluation is conducted on the original Mammographic Image Analysis Society (MIAS) and mini-MIAS databases, as well as our own Seoul National University Bundang Hospital digital mammographic database. It is shown that the proposed method outperforms comparable methods in terms of receiver operating characteristic (ROC) and precision-recall curves for detection of individual μCs and free-response receiver operating characteristic (FROC) curve for detection of clustered μCs. 相似文献
56.
Jin Il Kim Min-Woong Hwang Ilseob Lee Sehee Park Sangmoo Lee Joon-Yong Bae Jun Heo Donghwan Kim Seok-Il Jang Mee Sook Park Hyung-Joo Kwon Jin-Won Song Man-Seong Park 《Biochemical and biophysical research communications》2014
By nature of their segmented RNA genome, influenza A viruses (IAVs) have the potential to generate variants through a reassortment process. The influenza nonstructural (NS) gene is critical for a virus to counteract the antiviral responses of the host. Therefore, a newly acquired NS segment potentially determines the replication efficiency of the reassortant virus in a range of different hosts. In addition, the C-terminal PDZ-binding motif (PBM) has been suggested as a pathogenic determinant of IAVs. To gauge the pandemic potential from human and avian IAV reassortment, we assessed the replication properties of NS-reassorted viruses in cultured cells and in the lungs of mice and determined their transmissibility in guinea pigs. Compared with the recombinant A/Korea/01/2009 virus (rK09; 2009 pandemic H1N1 strain), the rK09/VN:NS virus, in which the NS gene was adopted from the A/Vietnam/1203/2004 virus (a human isolate of the highly pathogenic avian influenza H5N1 virus strains), exhibited attenuated virulence and reduced transmissibility. However, the rK09/VN:NS-PBM virus, harboring the PBM in the C-terminus of the NS1 protein, recovered the attenuated virulence of the rK09/VN:NS virus. In a guinea pig model, the rK09/VN:NS-PBM virus showed even greater transmission efficiency than the rK/09 virus. These results suggest that the PBM in the NS1 protein may determine viral persistence in the human and avian IAV interface. 相似文献
57.
Jung Woong Choi Seyoung Lim Yong-Seok Oh Eung-Kyun Kim Sun-Hee Kim Yun-Hee Kim Kyun Heo Jaeyoon Kim Jung Kuk Kim Yong Ryul Yang Sung Ho Ryu Pann-Ghill Suh 《Cellular signalling》2010,22(7):1153-1161
Among phospholipase C (PLC) isozymes (β, γ, δ, ε, ζ and η), PLC-β plays a key role in G-protein coupled receptor (GPCR)-mediated signaling. PLC-β subtypes are often overlapped in their distribution, but have unique knock-out phenotypes in organism, suggesting that each subtype may have the different role even within the same type of cells. In this study, we examined the possibility of the differential coupling of each PLC-β subtype to GPCRs, and explored the molecular mechanism underlying the specificity. Firstly, we found that PLC-β1 and PLC-β3 are activated by bradykinin (BK) or lysophosphatidic acid (LPA), respectively. BK-triggered phosphoinositides hydrolysis and subsequent Ca2+ mobilization were abolished specifically by PLC-β1 silencing, whereas LPA-triggered events were by PLC-β3 silencing. Secondly, we showed the evidence that PDZ scaffold proteins is a key mediator for the selective coupling between PLC-β subtype and GPCR. We found PAR-3 mediates physical interaction between PLC-β1 and BK receptor, while NHERF2 does between PLC-β3 and LPA2 receptor. Consistently, the silencing of PAR-3 or NHERF2 blunted PLC signaling induced by BK or LPA respectively. Taken together, these data suggest that each subtype of PLC-β is selectively coupled to GPCR via PDZ scaffold proteins in given cell types and plays differential role in the signaling of various GPCRs. 相似文献
58.
Sangryong Lee Sangtae Lee Kyeongin Heo Seung-Chul Kim 《Journal of plant research》2010,123(6):723-729
Symplocarpus L. (Araceae) is a disjunct genus including S. foetidus (L.) Nutt. var. latissimus (Makino) S. Hara, S. nipponicus Makino, and S. nabekuraensis Otsuka & K. Inoue in temperate eastern Asia; S. egorovii N. S. Pavlova & V. A. Nechaev in the Russian far east; and S. foetidus (L.) Nutt. in temperate northeastern North America. For the first time, pollen morphology of Symplocarpus was investigated by light and scanning electron microscopes. Symplocarpus foetidus var. latissimus and S. foetidus had reticulate surfaces and rounded (obtuse), long, equatorial axis tips, whereas S. nipponicus had microreticulate surfaces and acute tips. Symplocarpus foetidus in North America had larger pollen grains than S.
foetidus var. latissimus in eastern Asia. Thus, based on pollen characteristics, S. foetidus var. latissimus is more closely related to S. foetidus than to S. nipponicus. Other lines of evidence, such as molecular phylogenetic studies and phenology, support the phylogenetic relationships among
these species proposed in this study. The slightly modified acetolysis procedure conducted in this paper is a promising application
to study weak exine or exineless pollen grains. 相似文献
59.
Hyoung-Sam Heo Sanghyuk Lee Yeon Ja Choi S. June Oh 《Biochemical and biophysical research communications》2010,397(1):120-126
Peptide mass fingerprinting (PMF) has become one of the most widely used methods for rapid identification of proteins in proteomics research. Many peaks, however, remain unassigned after PMF analysis, partly because of post-translational modification and the limited scope of protein sequences. Almost all PMF tools employ only known or predicted protein sequences and do not include open reading frames (ORFs) in the genome, which eliminates the chance of finding novel functional peptides. Unlike most tools that search protein sequences from known coding sequences, the tool we developed uses a database for theoretical small ORFs (tsORFs) and a PMF application using a tsORFs database (tsORFdb). The tsORFdb is a database for ORFeome that encompasses all potential tsORFs derived from whole genome sequences as well as the predicted ones. The massProphet system tries to extend the search scope to include the ORFeome using the tsORFdb. The tsORFdb and massProphet should be useful for proteomics research to give information about unknown small ORFs as well as predicted and registered proteins. 相似文献
60.
Kwang Sung Ahn Ji Young Won Jin-Ki Park Alice M. Sorrell Soon Young Heo Jae-Seok Woo Won-Kyong Chang 《Biochemical and biophysical research communications》2010,400(4):667-672
This study was performed to produce transgenic pigs expressing the human complement regulatory protein CD59 (hCD59) using the nuclear transfer (NT) of embryonic germ (EG) cells, which are undifferentiated stem cells derived from primordial germ cells. Because EG cells can be cultured indefinitely in an undifferentiated state, they may provide an inexhaustible source of nuclear donor cells for NT to produce transgenic pigs. A total of 1980 NT embryos derived from hCD59-transgenic EG cells were transferred to ten recipients, resulting in the birth of fifteen piglets from three pregnancies. Among these offspring, ten were alive without overt health problems. Based on PCR analysis, all fifteen piglets were confirmed as hCD59 transgenic. The expression of the hCD59 transgene in the ten living piglets was verified by RT-PCR. Western analysis showed the expression of the hCD59 protein in four of the ten RT-PCR-positive piglets. These results demonstrate that hCD59-transgenic pigs could effectively be produced by EG cell NT and that such transgenic pigs may be used as organ donors in pig-to-human xenotransplantation. 相似文献