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51.
52.
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
53.
Food Biophysics - Caffeic acid phenethyl ester (CAPE) has high cytotoxicity against various cancer cells but has low water solubility and poor bioavailability. The objective of this work was to... 相似文献
54.
Jin YC Kim KJ Kim YM Ha YM Kim HJ Yun UJ Bae KH Kim YS Kang SS Seo HG Lee JH Chang KC 《Experimental biology and medicine (Maywood, N.J.)》2008,233(10):1280-1288
Magnolol, an active component extracted from Magnolia officinalis, has been reported to have protective effect on ischemia and reperfusion (I/R)-induced injury in experimental animals. The aim of the present investigation was to further evaluate the mechanism(s) by which magnolol reduces I/R-induced myocardial injury in rats in vivo. Under anesthesia, left anterior descending (LAD) coronary artery was occluded for 30 min followed by reperfusion for 24 h (for infarct size and cardiac function analysis). In some experiments, reperfusion was limited to 1 h or 6 h for analysis of biochemical and molecular events. Magnolol and DMSO solution (vehicle) were injected intra-peritoneally 1 h prior to I/R insult. The infarct size was measured by TTC technique and heart function was monitored by Millar Catheter. Apoptosis related events such as p-ERK, p-Bad, Bcl-xl and cytochrome c expression were evaluated by Western blot analysis and myocardial caspase-3 activity was also measured. Magnolol (10 mg/kg) reduced infarct size by 50% (P < 0.01 versus vehicle), and also improved I/R-induced myocardial dysfunction. Left ventricular systolic pressure and positive and negative maximal values of the first derivative of left ventricular pressure (dP/dt) were significantly improved in magnolol-treated rats. Magnolol increased the expression of phosphor ERK and Bad which resulted in inhibition of myocardial apoptosis as evidenced by TUNEL analysis and DNA laddering experiments. Application of PD 98059, a selective MEK1/2 inhibitor, strongly antagonized the effect of magnolol. Taken together, we concluded that magnolol inhibits apoptosis through enhancing the activation of ERK1/2 and modulation of the Bcl-xl proteins which brings about reduction of infarct size and improvement of cardiac function in I/R-induced injury. 相似文献
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56.
Bo Yeon Kim Kwang Sik Lee Mi Ri Sohn Soo Dong Woo Sung Sik Yoo Yeon Ho Je Byung Rae Jin 《Journal of Asia》2012,15(1):114-120
The expression of viral antigens in baculovirus-infected insect cells is often ineffective. As an alternative approach, therefore, we developed the recombinant polyhedra technology, which is an efficient strategy for the production of viral subunit vaccine. Here, we report a strategy for the large-scale production of a pseudorabies virus (PRV) gB or gC in the larvae of a baculovirus-infected silkworm, Bombyx mori. We constructed a recombinant B. mori nucleopolyhedrovirus (BmNPV) that expressed recombinant polyhedra together with the epitope regions of PRV gB or heparin-binding domains of PRV gC. Recombinant BmNPV-PRV-gB or BmNPV-PRV-gC-infected silkworm larvae expressed native polyhedrin and fusion protein that was detected using both anti-polyhedrin and anti-PRV gB or anti-PRV-gC antibodies. Electron and confocal microscopy demonstrated that the recombinant polyhedra contained both the fusion protein and native polyhedrin with a normal morphology and that the recombinant polyhedra contained PRV gB or gC. The yield of gB or gC antigen produced in BmNPV-PRV-gB or BmNPV-PRV-gC-infected silkworm larvae reached 0.69 or 0.46 mg per larva, respectively, at 6 days post-infection. These results demonstrate that the recombinant polyhedra strategy can be used for the large-scale production of PRV gB or gC antigen. 相似文献
57.
Yong-ho Lee Mi Hyang Kown Kwang Joon Kim Eun Young Lee Daham Kim Byung-Wan Lee Eun Seok Kang Bong Soo Cha Hyun Chul Lee 《PloS one》2014,9(9)
Background
Glycated albumin (GA) has been increasingly used as a reliable index for short-term glycemic monitoring, and is inversely associated with β-cell function. Because the pathophysiologic nature of type 2 diabetes (T2D) is characterized by progressive decline in insulin secretion, the aim was to determine whether GA levels were affected by diabetes duration in subjects with T2D.Methods
To minimize the effect of glucose variability on GA, subjects with stably maintained HbA1c levels of <0.5% fluctuation across 6 months of measurements were included. Patients with newly diagnosed T2D (n = 1059) and with duration>1 year (n = 781) were recruited and categorized as New-T2D and Old-T2D, respectively. Biochemical, glycemic, and C-peptide parameters were measured.Results
GA levels were significantly elevated in HbA1c-matched Old-T2D subjects compared to New-T2D subjects. Duration of diabetes was positively correlated with GA, whereas a negative relationship was found with C-peptide increment (ΔC-peptide). Among insulin secretory indices, dynamic parameters such as ΔC-peptide were inversely related to GA (r = −0.42, p<0.001). Multiple linear regression analyses showed that duration of diabetes was associated with GA (standardized β coefficient [STDβ] = 0.05, p<0.001), but not with HbA1c (STDβ = 0.04, p<0.095). This association disappeared after additional adjustment with ΔC-peptide (STDβ = 0.02, p = 0.372), suggesting that β-cell function might be a linking factor of close relationship between duration of diabetes and GA values.Conclusions
The present study showed that GA levels were significantly increased in subjects with longer duration T2D and with decreased insulin secretory function. Additional caution should be taken when interpreting GA values to assess glycemic control status in these individuals. 相似文献58.
Park SM Yan BC Park JH Choi JH Yoo KY Lee CH Baek YY Kim YM Kang IJ Won MH 《Cellular and molecular neurobiology》2012,32(3):423-434
Tetanus toxin (TeT), an exotoxin, has been studied to cause tetanus in mammalian brains, and it can block the release of some
neurotransmitters and affect seizure propagation. In the present study, we investigated neuronal damage/death and glial changes
in the mouse hippocampus after systemic administration (intraperitoneal injection) of TeT 10 and 100 ng/kg. In both the 10
and 100 ng/kg TeT-treated groups, no neuronal death occurred in any subregions of the mouse hippocampus until 24 h post-treatment;
however, there were changes in glia in the hippocampus depending on time course and dosage. The morphology of GFAP-immunoreactive
astrocytes and Iba-1-immunoreactive microglia was apparently changed in the 100 ng/kg TeT treated-group compared to the 10 ng/kg
TeT treated-group. In the 100 ng/kg TeT treated-group, they were increased in size and their immunoreactivity was distinctively
increased from 12 h post-treatment. We also found that their protein levels were increased in the hippocampus at 12 h post-treatment
of 100 ng/kg TeT. In conclusion, these results indicate that the systemic administration of 100 ng/kg TeT induced a distinctive
microglia changes in the mouse hippocampus without any neuronal death/damage. 相似文献
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60.
TrkB activation by 7, 8‐dihydroxyflavone increases synapse AMPA subunits and ameliorates spatial memory deficits in a mouse model of Alzheimer's disease 下载免费PDF全文