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21.
So Jeong Kim Sung Wan Byun Seung-Sin Lee 《International journal of clinical and experimental pathology》2013,6(12):2713-2718
Various types of diseases can involve the nasal vestibule. Diagnosis and treatment of a nasal vestibular mass is often challenging due to the anatomical features of the nasal vestibule. Here, we present four cases with nasal vestibular masses. Two cases were diagnosed as squamous papillomas. The others were a trichofolliculoma and pseudoepitheliomatous hyperplasia with hyperkeratosis. Our aim was to discuss the characteristics of each disease and the considerations thought to be necessary for diagnosis and treatment of nasal vestibular tumors from these cases and the related literature. 相似文献
22.
Hui‐Jeong Hwang M.D. Hyae‐Min Lee M.D. In‐Ho Yang M.D. Dong‐Hee Kim M.D. Jong‐Kyu Byun M.D. Il Suk Sohn M.D. 《Echocardiography (Mount Kisco, N.Y.)》2014,31(10):E293-E295
In this report, we introduce a case of thickening of the involved left ventricular apical segment on echocardiography and deep T‐wave inversions in precordial leads on electrocardiography transiently seen in the course of recovery from biventricular takotsubo cardiomyopathy, mimicking apical hypertrophic cardiomyopathy. This result suggests that the echocardiographic finding of transient myocardial edema can be identified by cardiac magnetic resonance imaging in takotsubo cardiomyopathy. Additionally, it persisted a few weeks after full functional recovery. We believe that this case will contribute in part toward clarifying the pathophysiology of takotsubo cardiomyopathy. 相似文献
23.
Jungwon Seo Jee Young Lee Min-Sun Sung Catherine Jeonghae Byun Du-Hyong Cho Hyeon-Ju Lee Jung-Hyun Park Ho-Seong Cho Sung-Jin Cho Inho Jo 《Biomolecules & therapeutics.》2014,22(6):510-518
Chronic (>24 h) exposure of arsenite, an environmental toxicant, has shown the decreased nitric oxide (NO) production in endothelial cells (EC) by decreasing endothelial NO synthase (eNOS) expression and/or its phosphorylation at serine 1179 (eNOS-Ser1179 in bovine sequence), which is associated with increased risk of vascular diseases. Here, we investigated the acute (<24 h) effect of arsenite on NO production using bovine aortic EC (BAEC). Arsenite acutely increased the phosphorylation of eNOS-Thr497, but not of eNOS-Ser116 or eNOS-Ser1179, which was accompanied by decreased NO production. The level of eNOS expression was unaltered under this condition. Treatment with arsenite also induced reactive oxygen species (ROS) production, and pretreatment with a ROS scavenger N-acetyl-L-cysteine (NAC) completely reversed the observed effect of arsenite on eNOS-Thr497 phosphorylation. Although protein kinase C (PKC) and protein phosphatase 1 (PP1) were reported to be involved in eNOS-Thr497 phosphorylation, treatment with PKC inhibitor, Ro318425, and overexpression of various PKC isoforms did not affect the arsenite-stimulated eNOS-Thr497 phosphorylation. In contrast, treatment with PP1 inhibitor, calyculin A, mimicked the observed effect of arsenite on eNOS-Thr497 phosphorylation. Lastly, we found decreased cellular PP1 activity in arsenite-treated cells, which was reversed by NAC. Overall, our study demonstrates firstly that arsenite acutely decreases NO production at least in part by increasing eNOS-Thr497 phosphorylation via ROS-PP1 signaling pathway, which provide the molecular mechanism underlying arsenite-induced increase in vascular disease. 相似文献
24.
25.
Hakmin Lee Minseung Lee Seok-Soo Byun Sang Eun Lee Sung Kyu Hong 《Clinical genitourinary cancer》2019,17(1):e221-e226
Introduction
The American Joint Committee on Cancer (AJCC) tumor, node, metastasis classification system (TNM) staging manual has been updated and provides more specified stage grouping for prostate cancer (PCa). We aimed to validate the updated AJCC stage groups for PCa using a radical prostatectomy (RP) cohort.Patients and Methods
We analyzed the data of 3032 patients previously treated with RP for localized PCa. We stratified patients into stage groups according to the 8th edition of the AJCC manual and compared biochemical recurrence (BCR)-free survival using Kaplan-Meier analyses.Results
There were 217 patients in stage group I, 33 in IIA, 1101 in IIB, 535 in IIC, 129 in IIIA, 781 in IIIB, and 236 in IIIC. There were no significant differences in BCR-free survival between stage groups IIC and IIIA (P = .875). Subsequently, the low–Gleason score (GS) IIIA subgroup (GS ≤ 3 + 4, P = .025) showed superior BCR-free survival than the IIC group, and the high-GS IIIA subgroups (GS ≥ 4 + 3, P = .004) showed a poorer BCR-free survival than the IIC group. Furthermore, there were no significant differences between groups I and IIA (P = 330) and between groups IIA and IIB (P = .942). Our new staging system provided a better ability to discriminate the prognosis of each group. However, our study has several limitations, such as retrospective design, relatively short follow-up period, and need for further validation.Conclusion
The current AJCC prognostic groups show some contradictory results, particularly concerning prognosis of the IIC and IIIA groups. We suggest that GS be given more weight than serum prostate-specific antigen level in stage group stratification. 相似文献26.
27.
Syed Bilal Ahmad Fiona E. McNeill Soo Hyun Byun William V. Prestwich Carmel Mothersill Colin Seymour Andrea Armstrong Cristian Fernandez 《Dose-response》2013,11(4):513-531
In this study, we aimed to establish the emission of UV photons when HPV-G cells and associated materials (such as the cell substrate and cell growth media) are exposed to low LET radiation. The potential role of UV photons in the secondary triggering of biological processes led us to hypothesize that the emission and absorption of photons at this wavelength explain some radiation induced “bystander effects” that have previously been thought to be chemically mediated. Cells were plated in Petri-dishes of two different sizes, having different thicknesses of polystyrene (PS) substrate, and were exposed to β-radiation from 90Y produced by the McMaster Nuclear Reactor. UV measurements were performed using a single photon counting system employing an interference-type filter for selection of a narrow wavelength range, 340±5 nm, of photons. Exposure of the cell substrates (which were made of polystyrene) determined that UV photons were being emitted as a consequence of β particle irradiation of the Petri-dishes. For a tightly collimated β-particle beam exposure, we observed 167 photons in the detector per unit μCi in the shielded source for a 1.76 mm thick substrate and 158 photons/μCi for a 0.878 mm thick substrate. A unit μCi source activity was equivalent to an exposure to the substrate of 18 β-particles/cm2 in this case. The presence of cells and medium in a Petri-dish was found to significantly increase (up to a maximum of 250%) the measured number of photons in a narrow band of wavelengths of 340±5 nm (i.e. UVA) as compared to the signal from an empty control Petri-dish. When coloured growth medium was added to the cells, it reduced the measured count rate, while the addition of transparent medium in equal volume increased the count rate, compared to cells alone. We attribute this to the fact that emission, scattering and absorption of light by cells and media are all variables in the experiment. Under collimated irradiation conditions, it was observed that increasing cell density in medium of fixed volume resulted in a decrease in the observed light output. This followed a roughly exponential decline. We suggest that this may be due to increased scattering at the cell boundary and absorption of the UV in the cells. We conclude that we have measured UVA emitted by cells, cell medium and cell substrates as a consequence of their irradiation by low LET β-particle radiation. We suggest that these secondary UV photons could lead to effects in non-targetted cells. Some effects that had previously been attributed to a chemically mediated “bystander effect” may in fact be due to secondary UV emission. Some radiation bystander effect studies may require re-interpretation as this phenomenon of UV emission is further investigated. 相似文献
28.
Epigenome‐wide DNA methylation changes with development of arsenic‐induced skin lesions in Bangladesh: A case–control follow‐up study 下载免费PDF全文
Wei Jie Seow Molly L. Kile Andrea A. Baccarelli Wen‐Chi Pan Hyang‐Min Byun Golam Mostofa Quazi Quamruzzaman Mahmuder Rahman Xihong Lin David C. Christiani 《Environmental and molecular mutagenesis》2014,55(6):449-456
Studies have found an association between aberrant DNA methylation and arsenic‐induced skin lesions. However, little is known about DNA methylation changes over time in people who develop arsenic‐induced skin lesions. We sought to investigate epigenome‐wide changes of DNA methylation in people who developed arsenic‐induced skin lesions in a 10‐year period. In 2009–2011, we conducted a follow‐up study of 900 skin lesion cases and 900 controls and identified 10 people who developed skin lesions since a baseline survey in 2001–2003. The 10 cases (“New Cases”) were matched with 10 controls who did not have skin lesions at baseline or follow‐up (“Persistent Controls”). Drinking water and blood samples were collected, and skin lesion was diagnosed by the same physician at both time points. We measured DNA methylation in blood using Infinium HumanMethylation450K BeadChip, followed by quantitative validation using pyrosequencing. Two‐sample t‐tests were used to compare changes in percent methylation between New Cases and Persistent Controls. Six CpG (cytosine‐phosphate‐guanine) sites with greatest changes of DNA methylation over time among New Cases were further validated with a correlation of 93% using pyrosequencing. One of the validated CpG site (cg03333116; change of %methylation was 13.2 in New Cases versus ?0.09 in Persistent Controls; P < 0.001) belonged to the RHBDF1 gene, which was previously reported to be hypermethylated in arsenic‐exposed cases. We examined DNA methylation changes with the development of arsenic‐induced skin lesions over time but nothing was statistically significant given the small sample size of this exploratory study and the high dimensionality of data. Environ. Mol. Mutagen. 55:449–456, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
29.
J. H. Kim H. J. Yim E. S. Jung Y. K. Jung J. H. Kim Y. S. Seo J. E. Yeon H. S. Lee S. H. Um K. S. Byun 《Journal of viral hepatitis》2011,18(4):287-293
Summary. Clevudine shows high rates of virologic and biochemical responses in patients with chronic hepatitis B. However, the efficacy and safety of clevudine in patients with cirrhosis are unknown. The aims of this study were to evaluate the safety and to assess the virologic and the biochemical responses to clevudine in patients with cirrhosis with chronic hepatitis B virus (HBV) infection. We reviewed data from treatment‐naïve patients with chronic hepatitis B with and without cirrhosis who started clevudine between April 2007 and March 2008 (n = 52, hepatitis B without cirrhosis n = 21 and chronic hepatitis B with cirrhosis n = 31) at Korea University Ansan/Guro Hospital. All of the patients were treated for more than 48 weeks. The mean age was older in the patients with cirrhosis. Baseline HBV DNA levels were 6.9 and 7.78 log copies/mL (P = 0.042), and alanine aminotransferase (ALT) levels were 104.9 and 147.4 IU/L (P = 0.204), for those with and without cirrhosis, respectively. Virologic response (HBV DNA <1000 copies/mL) (87.1%vs 71.4%, P = 0.24) and biochemical response (83.9%vs 80.9%, P = 0.99) at week 48 were not significantly different between the two groups. Early virologic response at week 12 was even higher in the patients with cirrhosis (61.3%vs 28.6%, P = 0.026). Neither ALT flare nor newly onset hepatic decompensation was found in the patients with cirrhosis, whereas ALT flare was transiently observed in 14.3% of the chronic hepatitis group. In conclusion, although clevudine may produce a transient elevation of ALT during the early treatment period, such findings were not observed in patients with cirrhosis and the virologic and biochemical responses of the groups were comparable. 相似文献
30.
High pesticide exposure events and DNA methylation among pesticide applicators in the agricultural health study 下载免费PDF全文