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51.
Hyung‐Ju Cho Jae Young Choi Yu‐Mi Yang Jeong Hee Hong Chang‐Hoon Kim Heon Young Gee Hyun Jae Lee Dong Min Shin Joo‐Heon Yoon 《Journal of cellular biochemistry》2010,109(6):1254-1263
Adequate fluid secretion from airway mucosa is essential for maintaining mucociliary clearance, and fluid hypersecretion is a prominent feature of inflammatory airway diseases such as allergic rhinitis. House dust mite extract (HDM) has been reported to activate protease‐activated receptors (PARs), which play various roles in airway epithelia. However, the role of HDM in regulating ion transporters and fluid secretion has not been investigated. We examined the effect of HDM on ion transport in human primary nasal epithelial cells. The Ca2+‐sensitive dye Fura2‐AM was used to determine intracellular Ca2+ concentration ([Ca2+]i) by means of spectrofluorometry in human normal nasal epithelial cells (NHNE). Short‐circuit current (Isc) was measured using Ussing chambers. Fluid secretion from porcine airway mucosa was observed by optical measurement. HDM extract (10 µg/Ml) effectively cleaved the PAR‐2 peptide and induced an increase of [Ca2+]i that was abolished by desensitization with trypsin, but not with thrombin. Apical application of HDM‐induced Isc sensitive to both a cystic fibrosis transmembrane conductance regulator (CFTR) inhibitor and a Ca2+‐activated Cl? channel (CaCC) inhibitor. HDM extract also stimulated fluid secretion from porcine airway mucosa. HDM extract activated PAR‐2 and apical Cl? secretion via CaCC and CFTR, and HDM‐induced fluid secretion in porcine airway mucosa. Our results suggest a role for PAR‐2 in mucociliary clearance and fluid hypersecretion of airway mucosa in response to air‐borne allergens such as HDM. J. Cell. Biochem. 109: 1254–1263, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
52.
Background
To investigate the hemodynamic characteristics of glaucoma eyes with disc hemorrhage (DH) by disc fluorescein angiography, and its relationship with glaucomatous changes of the optic disc and surrounding retinal nerve fiber layer (RNFL).Methods
This study included 35 glaucoma eyes with DH who were followed up at least 5 years and had DH at presentation. Eyes were classified as eyes with DH at the border of localized RNFL defects and eyes with DH not related to localized RNFL defects. Prevalence of DH and location of the proximal border were recorded from disc photographs. Fluorescein angiography was performed 3 months after detecting the DH. Arm-retina time, arteriovenous transit time, disc filling time, choroidal filling time, and venous filling time were measured as retinal circulation parameters. The presence of disc filling defects and disc leaks were evaluated.Results
There were 19 (54.3%) eyes with DH accompanying localized RNFL defects. The arm-retina time was prolonged in eyes with DH not related to RNFL defects (P = 0.044) and the arteriovenous transit time was prolonged in eyes with DH accompanying RNFL defects (P = 0.029). Among eyes with DH accompanying RNFL defects, 11 (57.9%) had vessel filling defects or delayed filling indicating blood flow stasis at the cup margin proximal to where DH occurred. Eyes with DH not related to RNFL defects did not show vessel filling defects or delayed filling.Conclusions and Relevance
Eyes with DH related to RNFL defects showed prolonged arteriovenous transit time and had frequent vessel filling defects or delayed filling indicating blood flow stasis and thrombus formation at the site DH occurred. These findings suggest that vascular and hemodynamic changes due to glaucomatous structural changes cause DH in relation to localized RNFL defects. 相似文献53.
A focal visual stimulus outside the classical receptive field (RF) of a V1 neuron does not evoke a spike response by itself, and yet evokes robust changes in the local field potential (LFP). This subthreshold LFP provides a unique opportunity to investigate how changes induced by surround stimulation leads to modulation of spike activity. In the current study, two identical Gabor stimuli were sequentially presented with a variable stimulus onset asynchrony (SOA) ranging from 0 to 100 ms: the first (S1) outside the RF and the second (S2) over the RF of primary visual cortex neurons, while trained monkeys performed a fixation task. This focal and asynchronous stimulation of the RF surround enabled us to analyze the modulation of S2-evoked spike activity and covariation between spike and LFP modulation across SOA. In this condition, the modulation of S2-evoked spike response was dominantly facilitative and was correlated with the change in LFP amplitude, which was pronounced for the cells recorded in the upper cortical layers. The time course of covariation between the SOA-dependent spike modulation and LFP amplitude suggested that the subthreshold LFP evoked by the S1 can predict the magnitude of upcoming spike modulation. 相似文献
54.
YR Kim JS Kim YH Min DH Yoon HJ Shin YC Mun Y Park YR Do SH Jeong JS Park SY Oh S Lee EK Park JS Jang WS Lee HW Lee H Eom JS Ahn J Jeong SK Baek SJ Kim WS Kim C Suh 《Journal of hematology & oncology》2012,5(1):49
ABSTRACT: BACKGROUND: The objective of this study was to identify prognostic factors for survival in patients with primary diffuse large B-cell lymphoma (DLBCL) of the adrenal gland. METHODS: Thirty one patients diagnosed with primary adrenal DLBCL from 14 Korean institutions and treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) were analyzed. RESULTS: Complete remission (CR) and overall response rate after R-CHOP chemotherapy were 54.8% and 87.0%. The 2-year estimates of overall survival (OS) and progression-free survival (PFS) were 68.3% and 51.1%. In patients achieving CR, significant prolongations of OS (P = 0.029) and PFS (P = 0.005) were observed. Ann Arbor stage had no influence on OS. There was no significant difference in OS between patients with unilateral involvement of adrenal gland and those with bilateral involvement. When staging was modified to include bilateral adrenal involvement as one extranodal site, early stage (I or II) significantly correlated with longer OS (P = 0.021) and PFS (P <0.001). CONCLUSIONS: Contrary to prior reports, our data suggests that outcomes of primary adrenal DLBCL are encouraging using a regimen of R-CHOP, and that achieving CR after R-CHOP is predictive of survival. Likewise, our modified staging system may have prognostic value. 相似文献
55.
Kim DM Yun NR Neupane GP Shin SH Ryu SY Yoon HJ Wie SH Kim WJ Lee CY Choi JS Yang TY 《PloS one》2011,6(8):e22731
Background
Scrub typhus is an infectious disease caused by Orientia tsutsugamushi. The differences in virulence of O. tsutsugamushi prototypes in humans are still unknown. We investigated whether there are any differences in the clinical features of the Boryoung and Karp genotypes.Methodology/Principal Findings
Patients infected with O. tsutsugamushi, as Boryoung and Karp clusters, who had visited 6 different hospitals in southwestern Korea were prospectively compared for clinical features, complications, laboratory parameters, and treatment responses. Infected patients in the Boryoung cluster had significantly more generalized weakness, eschars, skin rashes, conjunctival injection, high albumin levels, and greater ESR and fibrinogen levels compared to the Karp cluster. The treatment response to current antibiotics was significantly slower in the Karp cluster as compared to the Boryoung cluster.Conclusion
The frequency of occurrence of eschars and rashes may depend on the genotype of O. tsutsugamushi. 相似文献56.
Soowan Kim Minhyung Jung Yoon‐Jae Song Se Chan Kang BaeYong Kim I‐Jin Choi Hong Geun Kim Doo‐Hyung Lee 《Entomological Research》2017,47(3):208-216
The sweetpotato whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), is a major pest on greenhouse crops including sweet pepper (Capsicum annuum L.), which is one of the leading greenhouse crops in South Korea. Synthetic insecticides, especially the neonicotinoids, have been used to conventionally control this pest. There have been continuous efforts to develop plant‐derived compounds as insecticides, deterrents, and repellents to reduce spraying synthetic insecticides. To develop new plant‐extract insecticides, we investigated the insecticidal effects of Perilla sp. (Perilla frutescens var. crispa) extract on B. tabaci in laboratory conditions. The Perilla sp. extract induced 90 % mortality within one hour, but phytotoxicity symptoms on sweet pepper leaves were also observed. We monitored the population change and spatial distribution of adult B. tabaci in an experimental sweet pepper greenhouse using yellow sticky traps, and analyzed distribution patterns by spatial analysis with distance indices (SADIE). Based on monitoring data and SADIE analysis, we concluded that B. tabaci aggregated near the greenhouse entrances, and it showed aggregation and association pattern as time passed. Therefore, we recommend spraying Perilla sp. extract near the entrances or wild host before the pest population penetrates. It will be one of the alternative pest management strategies to reduce B. tabaci population with fewer negative effects from chemical insecticide. Further study is required to reduce the phytotoxicity symptoms from Perilla sp. extract spray and insecticidal effect should be evaluated under field conditions. 相似文献
57.
58.
Structural chemoproteomics and drug discovery 总被引:1,自引:0,他引:1
Shin D Heo YS Lee KJ Kim CM Yoon JM Lee JI Hyun YL Jeon YH Lee TG Cho JM Ro S 《Biopolymers》2005,80(2-3):258-263
Our laboratories have developed several technologies to accelerate drug discovery process on the basis of structural chemoproteomics. They include SPS technology for the efficient determination of protein structures, SCP technology for the rapid lead generation and SDF technology for the productive lead optimization. Using these technologies, we could determine many 3D structures of target proteins bound with biologically active chemicals including the structure of phosphodiesterase 5/Viagra complex and obtain highly potent compounds in animal models of obesity, diabetes, cancer and inflammation. In this paper, we will discuss concepts and applications of structural chemoproteomics for drug discovery. 相似文献
59.
Yoon YS Yoon DS Lim IK Yoon SH Chung HY Rojo M Malka F Jou MJ Martinou JC Yoon G 《Journal of cellular physiology》2006,209(2):468-480
Enlarged or giant mitochondria have often been documented in aged tissues although their role and underlying mechanism remain unclear. We report here how highly elongated giant mitochondria are formed in and related to the senescent arrest. The mitochondrial morphology was progressively changed to a highly elongated form during deferoxamine (DFO)-induced senescent arrest of Chang cells, accompanied by increase of intracellular ROS level and decrease of mtDNA content. Interestingly, under exposure to subcytotoxic doses of H2O2 (200 microM), about 65% of Chang cells harbored elongated mitochondria with senescent phenotypes whereas ethidium bromide (EtBr) (50 ng/ml) only reformed the cristae structure. Elongated giant mitochondria were also observed in TGF beta1- or H2O2-induced senescent Mv1Lu cells and in old human diploid fibroblasts (HDFs). In all senescent progresses employed in this study Fis1 protein, a mitochondrial fission modulator, was commonly downexpressed. Overexpression of YFP-Fis1 reversed both mitochondrial elongation and appearance of senescent phenotypes induced by DFO, implying its critical involvement in the arrest. Finally, we found that direct induction of mitochondrial elongation by blocking mitochondrial fission process with Fis1-DeltaTM or Drp1-K38A was sufficient to develop senescent phenotypes with increased ROS production. These data suggest that mitochondrial elongation may play an important role as a mediator in stress-induced premature senescence. 相似文献
60.
Kim ND Yoon J Kim JH Lee JT Chon YS Hwang MK Ha I Song WJ 《Bioorganic & medicinal chemistry letters》2006,16(14):3772-3776
Mental retardation is the most common and debilitating condition for individuals with Down syndrome (DS). The hyper-activation of DYRK1A by overexpression causes significant learning and memory deficits in DS-model mice. Thus far, no mechanism-based drug has been developed to address this. After a combination of in silico and in vitro screenings, two DYRK1A inhibitors were isolated that are active in a cell-based assay. Further optimization could lead to a novel drug discovery that could address DS learning and memory deficits. 相似文献