• Molecules and Cells
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• v.45 no.12
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• pp.923-934
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• 2022

Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have great potential in applications such as regenerative medicine, cardiac disease modeling, and in vitro drug evaluation. However, hPSC-CMs are immature, which limits their applications. During development, the maturation of CMs is accompanied by a decline in their proliferative capacity. This phenomenon suggests that regulating the cell cycle may facilitate the maturation of hPSC-CMs. Aurora kinases are essential kinases that regulate the cell cycle, the role of which is not well studied in hPSC-CM maturation. Here, we demonstrate that CYC116, an inhibitor of Aurora kinases, significantly promotes the maturation of CMs derived from both human embryonic stem cells (H1 and H9) and iPSCs (induced PSCs) (UC013), resulting in increased expression of genes related to cardiomyocyte function, better organization of the sarcomere, increased sarcomere length, increased number of mitochondria, and enhanced physiological function of the cells. In addition, a number of other Aurora kinase inhibitors have also been found to promote the maturation of hPSC-CMs. Our data suggest that blocking aurora kinase activity and regulating cell cycle progression may promote the maturation of hPSC-CMs.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4187-4193
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• 2013

Background: Evaluation of Human papilloma virus (HPV) and its association with promoter methylation of candidate genes, p53 and Aurora A in esophageal cancer. Materials and Methods: One hundred forty-one esophageal tissue samples from different pathologies were evaluated for HPV infection by PCR, while the promoter methylation status of p53 and Aurora A was assessed by methylation-specific restriction based PCR assay. Statistical analyses were performed with MedCalc and MDR software. Results: Based on endoscopy and histopathology, samples were categorized: cancers (n=56), precancers (n=7), esophagitis (n=19) and normals (n=59). HPV infection was found to be less common in cancers (19.6%), whereas its prevalence was relatively high in precancers (71.4%), esophagitis (57.8%) and normals (45.7%). p53 promoter methylation did not show any significant difference between cancer and normal tissues, whereas Aurora A promoter methylation demonstrated significant association with disease (p=0.00016, OR:5.6452, 95%CI:2.18 to 14.6) when compared to normals. Aurora A methylation and HPV infection was found in a higher percentages of precancer (66.6%), esophagitis (54.5%) and normal (45.2%) when compared to cancers (14.2%). Conclusions: Aurora A promoter methylation is significantly associated with esophageal cancer, but the effect of HPV infection on this epigenetic alteration is not significant. However MDR analysis showed that the hypostatic effect of HPV was nullified when the cases had Aurora methylation and tobacco exposure. Further HPV sub-typing may give an insight into its reduced prevalence in esophageal cancer verses normal tissue. However, with the present data it is difficult to assign any significant role to HPV in the etiopathology of esophageal cancer.

• Publications of The Korean Astronomical Society
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• v.13 no.1 s.14
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• pp.181-208
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• 1998

We have analyzed the sunspot and aurora data recorded in Go-Ryer-Sa. We have collected 35 records of sunspot observations for 46 days, and 232 records of auroral observations. To objectively estimate the periods of the solar activity appearing in these records a method of calculating the one-dimensional power spectrum from inhomogeneous data is developed, and applied to the sunspot and auroral data. We have found statistically significant 10.5 and 10 year periodicities in the distributions of sunspot and aurora records, respectively. These periods are consistent with the well-known solar activity cycle. There are indications of the long-term variations, but the period is not certain. We have also calculated the cross-correlations between the sunspot and auroral data. In particular, we have divided the aurora data into several subgroups to study their nature. We conclude that the historical records of strong auroral activity correspond to non-recurrent magnetic storms related to the sunspots. On the other hand, the records of weak auroral activity are thought to be related with the recurrent magnetic storms which occur frequently due to the coronal hole near the sunspot minimum.

• Reproductive and Developmental Biology
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• v.35 no.4
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• pp.499-502
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• 2011

Aurora A kinase is a mitotic serine/threonine kinase whose proposed functions include the maturation of centrosomes, G2/M transition, alignment of chromosomes at metaphase, and cytokinesis. In this study, we investigated the effect of MLN8237, an aurora A kinase inhibitor, on the postovulatory aging of oocytes based on the frequency of oocyte fragmentation, cdk1 kinase activity, and cyclin B degradation. The fragmentation of ovulated oocytes during prolonged culture was inhibited by treatment with MLN8237 in a concentration-dependent manner. The frequency of fragmented oocytes was significantly lower in oocytes treated with 2 ${\mu}M$ MLN8237 (13%) than in control oocytes (64%) after two days of culture. Most of the control (non-fragmented) oocytes (91%) were activated after two days of culture. In comparison, only 22% of the MLN8237-treated oocytes were activated; the rest of the oocytes (78%) were still in metaphase with an abnormal spindle and dispersed chromosomes. Next, cdk1 activity and the level of cyclin B were examined. The level of cyclin B and cdk1 activity in MLN8237-treated oocytes were nearly equal to those in control oocytes. Our results indicate that MLN8237 inhibited the fragmentation of ovulated oocytes during prolonged culture, although it blocked the spontaneous decrease in activity of cdk1 and degradation of cyclin B. This mechanism of inhibition is different from that in oocytes treated with nocodazole, which have high levels of cdk1 activity and cyclin B.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.8-14
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• 2011

This study was conducted to investigate the effect of age of transplants, propagated by cutting, of two cut rose (Rosa hybrida Hort.) cultivars on their subsequent growth and yield in an effort to develop an efficient cutting propagation method for domestic rose cultivars. Two cultivars used in this study were a standard type 'Pink Aurora' and a spray type 'Yellow King'. Cuttings were prepared as single node cuttings each with a five-leaflet leaf and were stuck in rockwool cubes ($5cm{\times}5cm{\times}5cm$, UR, Korea) at two different dates. Cuttings rooted for either 30 (stuck on Jan. 20, 2009) or 48 days (stuck on Jan. 2, 2009) were transplanted into a rockwool slabs ($10cm{\times}15cm{\times}100cm$, UR, Korea) on the same date, 18 Feb. 2009. Plant growth and cut flower quality were investigated for two successive harvests during the period of Jan. to July in 2009. In both cultivars, 48 days old plants showed some growth of the shoot and root before transplanting. However, in the case of 30 days old plants before transplanting no noticeable growth of the shoot and root was obserable in 'Pink Aurora', while only shoot growth, but not root growth to the bottom of the rooting medium, was observed in 'Yellow King'. This suggested cultivar-specific responses that in this experiment a spray type 'Yellow King' showed greater growth rate during the rooting stage than a standard type 'Pink Aurora'. In the measurement of growth and cut flower yield after transplanting, the 48 days old standard type 'Pink Aurora' produced greater number of cut flowers per plant than 30 days old plants, whereas their mean stem fresh weight was recorded smaller than that of the 30 days old plants. For 'Yellow King', 30 days old plants showed greater stem length, flower width, number of five-leaflet leaves per stem, stem fresh weight, and number of cut flowers per plant than 48 days old plants. Therefore, growth and yield were significantly affected by cultivar and age of the rooted cutting, and additional research is needed on the effect of age of rooted cuttings in more cultivars.

• Restorative Dentistry and Endodontics
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• v.32 no.5
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• pp.459-468
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• 2007

Protein microarray or protein chips is potentially powerful tools for analysis of protein-protein interactions. APin cDNA was previously identified and cloned from a rat odontoblast cDNA library. The purpose of this study was to investigate the APin-protein interactions during ameloblast differentiation. Protein microarray was carried with recombinant APin protein and MEF2, Aurora kinase A, BMPR-IB and EF-hand calcium binding protein were selected among 74 interacting proteins. Immortalized ameloblast cells (ALCs) were transfected with pCMV-APin construct and U6-APin siRNA construct. After transfection, the expression of the mRNAs for four proteins selected by protein micoarrays were assessed by RT-PCR. The results were as follows: 1. APin expression was increased and decreased markedly after its over-expression and inactivation, respectively. 2. Over-expression of the APin in the ALCs markedly down-regulated the expression of MEF2 and Aurora kinase A, whereas their expression remained unchanged by its inactivation. 3. Expression of BMPR-IB and EF-hand calcium binding protein were markedly increased by the over-expression of the APin in the ALCs, whereas expression of BMPR-IB remained unchanged and expression of EF-hand calcium binding protein was markedly decreased by its inactivation. These results suggest that APin plays an important role in ameloblast differentiation and mineralization by regulating the expression of MEF2, Aurora kinase A, BMPR-IB and EF-hand calcium binding protein.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.11-17
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• 2015

The study was conducted to investigate the effect of rootstock on growth and early yield of stenting-propagated cut roses (Rosa hybrida Hort.) 'Pink Aurora' and 'Yellow King'. The scions, prepared as single-node cuttings, each with a five-leaflet leaf, were grafted onto cuttings of Rosa indica 'Major', Rosa multiflora 'Chille Wonye No. 1', Rosa multiflora 'K-1', or Rosa multiflora 'Burr' as the rootstock. The rootstock cuttings were removed of all leaves and buds before grafting. The base of scion and the top of rootstock were held together and simultaneously cut at a $45^{\circ}$ angle for ease of grafting. Scion-rootstock unions were stuck in rockwool cubes and placed on a misted glasshouse bench for rooting before being transplanted into a rockwool slabs for cultivation. Rooting was the greatest in the 'Pink Aurora' and 'Yellow King' grafted on the rootstock Rosa indica 'Major'. In 'Pink Aurora', stem length, stem diameter, five-leaflet leaves per stem, and stem fresh weight of the harvested cut flowers were not affected by the rootstock. The greatest total yield of 'Pink Aurora' was obtained in plants grafted onto the Rosa indica 'Major' rootstock. Overall growth of 'Yellow King' was the greatest in plants grafted onto Rosa multiflora 'Burr' rootstock, although total yield was not affected by the rootstock. These results suggest that Rosa indica 'Major' is the most effective rootstock not only for rooting, but also for early yield and growth for stenting propagation of these cut roses.

• Journal of Ginseng Research
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• v.46 no.3
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• pp.481-488
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• 2022

Background: Although the tumor-suppressive effects of ginsenosides in cell cycle have been well established, their pharmacological properties in mitosis have not been clarified yet. The chromosomal instability resulting from dysregulated mitotic processes is usually increased in cancer. In this study, we aimed to investigate the anticancer effects of ginsenoside Rg1 on mitotic progression in cancer. Materials and methods: Cancer cells were treated with ginsenoside Rg1 and their morphology and intensity of different protein were analyzed using immunofluorescence microscopy. The level of proteins in chromosomes was compared through chromosomal fractionation and Western blot analyses. The location and intensity of proteins in the chromosome were confirmed through immunostaining of mitotic chromosome after spreading. The colony formation assays were conducted using various cancer cell lines. Results: Ginsenoside Rg1 reduced cancer cell proliferation in some cancers through inducing mitotic arrest. Mechanistically, it inhibits the phosphorylation of histone H3 Thr3 (H3T3ph) mediated by Haspin kinase and concomitant recruitment of chromosomal passenger complex (CPC) to the centromere. Depletion of Aurora B at the centromere led to abnormal centromere integrity and spindle dynamics, thereby causing mitotic defects, such as increase in the width of the metaphase plate and spindle instability, resulting in delayed mitotic progression and cancer cell proliferation. Conclusion: Ginsenoside Rg1 reduces the level of Aurora B at the centromere via perturbing Haspin kinase activity and concurrent H3T3ph. Therefore, ginsenoside Rg1 suppresses cancer cell proliferation through impeding mitotic processes, such as chromosome alignment and spindle dynamics, upon depletion of Aurora B from the centromere.

• Journal of Astronomy and Space Sciences
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• v.38 no.4
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• pp.203-215
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• 2021

The auroral observation has been started at Jang Bogo Station (JBS), Antarctica by using a visible All-sky camera (v-ASC) in 2018 to routinely monitor the aurora in association with the simultaneous observations of the ionosphere, thermosphere and magnetosphere at the station. In this article, the auroral observations are introduced with the analysis procedure to recognize the aurora from the v-ASC image data and to compute the auroral occurrences and the initial results on their spatial and temporal distributions are presented. The auroral occurrences are mostly confined to the northern horizon in the evening sector and extend to the zenith from the northwest to cover almost the entire sky disk over JBS at around 08 MLT (magnetic local time; 03 LT) and then retract to the northeast in the morning sector. At near the magnetic local noon, the occurrences are horizontally distributed in the northern sky disk, which shows the auroral occurrences in the cusp region. The results of the auroral occurrences indicate that JBS is located most of the time in the polar cap near the poleward boundary of the auroral oval in the nightside and approaches closer to the oval in the morning sector. At around 08 MLT (03 LT), JBS is located within the auroral oval and then moves away from it, finally being located in the cusp region at the magnetic local noon, which indicates that the location of JBS turns out to be ideal to investigate the variabilities of the poleward boundary of the auroral oval from long-term observations of the auroral occurrences. The future plan for the ground auroral observations near JBS is presented.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.10a
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• pp.336-345
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• 2004