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991.
992.
Up-regulation of cell adhesion molecules and proinflammatory cytokines contributes to enhanced monocyte adhesiveness and infiltration into the skin, during the pathogenesis of various inflammatory skin diseases, including atopic dermatitis. In this study, we examined the anti-inflammatory effects of butein, a tetrahydroxychalcone, and its action mechanisms using TNF-α-stimulated keratinocytes. Butein significantly inhibited TNF-α-induced ICAM-I expression and monocyte adhesion in human keratinocyte cell line HaCaT. Butein also decreased TNF-α-induced pro-inflammatory mediators, such as IL-6, IP-10 and MCP-1, in HaCaT cells. Butein decreased TNF-α-induced ROS generation in a dose-dependent manner in HaCaT cells. In addition, treatment of HaCaT cells with butein suppressed TNF-α-induced MAPK activation. Furthermore, butein suppressed TNF-α-induced NF-kappaB activation. Overall, our results indicate that butein has immunomodulatory activities by inhibiting expression of proinflammatory mediators in keratinocytes. Therefore, butein may be used as a therapeutic agent for the treatment of inflammatory skin diseases. [BMB Reports 2015; 48(9): 495-500] 相似文献
993.
Seng Jin Choi Min-Hye Kim Jinseong Jeon Oh Youn Kim Youngwoo Choi Jihye Seo Sung-Wook Hong Won-Hee Lee Seong Gyu Jeon Yong Song Gho Young-Koo Jee Yoon-Keun Kim 《PloS one》2015,10(9)
Staphylococcus aureus is an important pathogenic bacterium that causes various infectious diseases. Extracellular vesicles (EVs) released from S. aureus contain bacterial proteins, nucleic acids, and lipids. These EVs can induce immune responses leading to similar symptoms as during staphylococcal infection condition and have the potential as vaccination agent. Here, we show that active immunization (vaccination) with S. aureus-derived EVs induce adaptive immunity of antibody and T cell responses. In addition, these EVs have the vaccine adjuvant ability to induce protective immunity such as the up-regulation of co-stimulatory molecules and the expression of T cell polarizing cytokines in antigen-presenting cells. Moreover, vaccination with S. aureus EVs conferred protection against lethality induced by airway challenge with lethal dose of S. aureus and also pneumonia induced by the administration of sub-lethal dose of S. aureus. These protective effects were also found in mice that were adoptively transferred with splenic T cells isolated from S. aureus EV-immunized mice, but not in serum transferred mice. Furthermore, this protective effect of S. aureus EVs was significantly reduced by the absence of interferon-gamma, but not by the absence of interleukin-17. Together, the study herein suggests that S. aureus EVs are a novel vaccine candidate against S. aureus infections, mainly via Th1 cellular response. 相似文献
994.
Chang Hee Jung Gi Hyeon Seo Sunghwan Suh Ji Cheol Bae Mee Kyoung Kim You-Cheol Hwang Jae Hyeon Kim Byung-Wan Lee 《PloS one》2015,10(6)
Background
Whether diabetic patients without a history of coronary heart disease (CHD) have the same risk of CHD events as non-diabetic patients with a history of CHD remains controversial. This study aimed to determine whether type 2 diabetes mellitus (T2DM) is a coronary heart disease (CHD) equivalent in the need for coronary revascularization procedures (RVs) in the Korean population.Methodology/Principal Findings
We followed 2,168,698 subjects who had oral anti-diabetic drugs (OADs)-taking T2DM in 2008 and/or CHD in 2007–2008 (i.e., recent CHD). We used systematic datasets from the nationwide claims database of the Health Insurance Review and Assessment service of Korea, which is representative of the whole population of Korea, from January 2007 to December 2012. The primary study endpoint was the development of need for RVs (i.e., incident CHD) after January 2009 among three groups based on their status of T2DM and recent CHD, i.e., T2DM only, recent CHD only, and both T2DM and recent CHD. After adjustment for age and sex, patients with recent CHD only had 2.14 times the risk of incident CHD (95% CI, 2.11–2.18, P<0.001) compared with patients with T2DM only. Patients with both T2DM and recent CHD demonstrated approximately 2-fold increased risk of incident CHD compared with subjects with recent CHD only (95% CI, 1.75-1.82), while 4-fold increased risk compared with subjects with T2DM only (95% CI, 3.71-3.87). The risk of incident CHD also differed according to sex and age.Conclusions/Significance
This analysis of data from the nationwide claims database revealed that T2DM did not have a recent CHD equivalent risk in the Korean population. These results suggest that an appropriate strategy for the CHD risk stratification in diabetic patients should be adopted to manage this population. 相似文献995.
996.
997.
Biyun Ching Jia M. Woo Kum C. Hiong Mel V. Boo Celine Y. L. Choo Wai P. Wong Shit F. Chew Yuen K. Ip 《PloS one》2015,10(3)
This study aimed to obtain the coding cDNA sequences of Na+/K+-ATPase α (nkaα) isoforms from, and to quantify their mRNA expression in, the skeletal muscle (SM), the main electric organ (EO), the Hunter’s EO and the Sach’s EO of the electric eel, Electrophorus electricus. Four nkaα isoforms (nkaα1c1, nkaα1c2, nkaα2 and nkaα3) were obtained from the SM and the EOs of E. electricus. Based on mRNA expression levels, the major nkaα expressed in the SM and the three EOs of juvenile and adult E. electricus were nkaα1c1 and nkaα2, respectively. Molecular characterization of the deduced Nkaα1c1 and Nkaα2 sequences indicates that they probably have different affinities to Na+ and K+. Western blotting demonstrated that the protein abundance of Nkaα was barely detectable in the SM, but strongly detected in the main and Hunter’s EOs and weakly in the Sach’s EO of juvenile and adult E. electricus. These results corroborate the fact that the main EO and Hunter’s EO have high densities of Na+ channels and produce high voltage discharges while the Sach’s EO produces low voltage discharges. More importantly, there were significant differences in kinetic properties of Nka among the three EOs of juvenile E. electricus. The highest and lowest V
max of Nka were detected in the main EO and the Sach’s EO, respectively, with the Hunter’s EO having a V
max value intermediate between the two, indicating that the metabolic costs of EO discharge could be the highest in the main EO. Furthermore, the Nka from the main EO had the lowest Km (or highest affinity) for Na+ and K+ among the three EOs, suggesting that the Nka of the main EO was more effective than those of the other two EOs in maintaining intracellular Na+ and K+ homeostasis and in clearing extracellular K+ after EO discharge. 相似文献
998.
999.
Freeze-Dried Targeted Mannosylated Selenium-Loaded Nanoliposomes: Development and Evaluation 总被引:1,自引:0,他引:1
Susanne R. Youngren Rohit Mulik Byoung Jun Peter R. Hoffmann Kenneth R. Morris Mahavir B. Chougule 《AAPS PharmSciTech》2013,14(3):1012-1024
The aim of this investigation was to develop and evaluate freeze-dried mannosylated liposomes for the targeted delivery of selenium. Dipalmitoylphosphatidylcholine, distearoylphosphatidylglycerol, and cholesterol were dissolved in a chloroform and methanol mixture and allowed to form a thin film within a rotatory evaporator. This thin film was hydrated with a sodium selenite (5.8 μM) solution to form multilamellar vesicles and homogenized under high pressure to yield unilamellar nanoliposomes. Se-loaded nanoliposomes were mannosylated by 0.1% w/v mannosamine (Man-Lip-Se) prior to being lyophilized. Mannosamine concentration was optimized with cellular uptake studies in M receptor expressing cells. Non-lyophilized and lyophilized Man-Lip-Se were characterized for size, zeta potential, and entrapment efficiency. The influence of liposomal composition on the characteristics of Man-Lip-Se were evaluated using acidic and basic medium for 24 h. Thermal analysis and powder X-ray diffraction were used to determine the interaction of components within the Man-Lip-Se. The size, zeta potential and entrapment efficiency of the optimum Man-Lip-Se were observed to be 158 ± 28.9 nm, 33.21 ± 0.89 mV, and 77.27 ± 2.34%, respectively. An in vitro Se release of 70–75% up to 24 h in PBS pH 6.8 and <8% Se release in acidic media (0.1 N HCl) in 1 h was observed. The Man-Lip-Se were found to withstand gastric-like environments and showed sustained release. Stable freeze-dried Man-Lip-Se were successfully formulated with a size of <200 nm, ∼75% entrapment, and achieved controlled release of Se with stability under acidic media, which may be of importance in the targeted delivery of Se to the immune system.
Electronic supplementary material
The online version of this article (doi:10.1208/s12249-013-9988-3) contains supplementary material, which is available to authorized users.Key words: mannosylation, nanoliposome, selenium, thermal properties 相似文献1000.
Abstract Kaempferia galanga is a monocotyledonous plant of the Zingiberaceae family, commonly utilized for medicinal purposes. This study evaluates the effect of different concentrations of sucrose, benzylaminopurine (BA) and photoperiod on in vitro propagation of K. galanga. Murashige and Skoog (MS) medium supplemented with 5 mg L?1 BA and 30 g L?1 sucrose, and a photoperiod with 4 h of light induced the highest shoot proliferation (7.4 ± 1.0 shoots/explant) and the highest number of roots/shoot (31.3 ± 3.2). On the contrary, the maximum shoot height (4.7 ± 0.7 cm) and the highest number of leaves/shoot (4.7 ± 0.2) were obtained from cultures using MS medium supplemented with 30 g L?1 sucrose but without BA, and exposed to 16 h of light. Hence MS medium supplemented with 5 mg L?1 BA and 30 g L?1 sucrose, and incubated under a 4 h light/20 h dark photoperiod was chosen as the optimal protocol for mass multiplication of K. galanga. This in-vitro technique can facilitate the production of a large number of uniform plants of K. galanga, irrespective of the seasonal factor, and could be used as a tool for conservation of the species. 相似文献