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931.
Investigation on the Tribological Behavior and Wear Mechanism of Five Different Veneering Porcelains
Objectives
The primary aim of this research was to investigate the wear behavior and wear mechanism of five different veneering porcelains.Methods
Five kinds of veneering porcelains were selected in this research. The surface microhardness of all the samples was measured with a microhardness tester. Wear tests were performed on a ball-on-flat PLINT fretting wear machine, with lubrication of artificial saliva at 37°C. The friction coefficients were recorded by the testing system. The microstructure features, wear volume, and damage morphologies were recorded and analyzed with a confocal laser scanning microscope and a scanning electron microscope. The wear mechanism was then elucidated.Results
The friction coefficients of the five veneering porcelains differ significantly. No significant correlation between hardness and wear volume was found for these veneering porcelains. Under lubrication of artificial saliva, the porcelain with higher leucite crystal content exhibited greater wear resistance. Additionally, leucite crystal size and distribution in glass matrix influenced wear behavior. The wear mechanisms for these porcelains were similar: abrasive wear dominates the early stage, whereas delamination was the main damage mode at the later stage. Furthermore, delamination was more prominent for porcelains with larger crystal sizes.Significance
Wear compatibility between porcelain and natural teeth is important for dental restorative materials. Investigation on crystal content, size, and distribution in glass matrix can provide insight for the selection of dental porcelains in clinical settings. 相似文献932.
Na-Young Ha Prashant Sharma Gwanghun Kim Yuri Kim Chan-Ki Min Myung-Sik Choi Ik-Sang Kim Nam-Hyuk Cho 《PLoS neglected tropical diseases》2015,9(3)
BackgroundScrub typhus is an acute febrile disease caused by Orientia tsutsugamushi infection. Recently, the rapid increase of scrub typhus incidence in several countries within the endemic region has become a serious public health issue. Despite the wide range of preventative approaches that have been attempted in the past 70 years, all have failed to develop an effective prophylactic vaccine. Currently, the selection of the proper antigens is one of the critical barriers to generating cross-protective immunity against antigenically-variable strains of O. tsutsugamushi.Conclusions/SignificanceImmunization of ScaA proteins provides protective immunity in mice when challenged with the homologous strain and significantly enhanced protective immunity against infection with heterologous strains. To our knowledge, this is the most promising result of scrub typhus vaccination trials against infection of heterologous strains in mouse models thus far. 相似文献
933.
See-Hyoung Park Sang Jae Noh Kyoung Min Kim Jun Sang Bae Keun Sang Kwon Sung Hoo Jung Jung Ryul Kim Ho Lee Myoung Ja Chung Woo Sung Moon Myoung Jae Kang Kyu Yun Jang 《Translational oncology》2015,8(4):239-249
BACKGROUND: Poly(ADP-ribose) polymerase 1 (PARP1), γH2AX, BRCA1, and BRCA2 are conventional molecular indicators of DNA damage in cells and are often overexpressed in various cancers. In this study, we aimed, using immunohistochemical detection, whether the co-expression of PARP1, γH2AX, BRCA1, and BRCA2 in breast carcinoma (BCA) tissue can provide more reliable prediction of survival of BCA patients. MATERIALS AND METHODS: We investigated immunohistochemical expression and prognostic significance of the expression of PARP1, γH2AX, BRCA1, and BRCA2 in 192 cases of BCAs. RESULTS: The expression of these four molecules predicted earlier distant metastatic relapse, shorter overall survival (OS), and relapse-free survival (RFS) by univariate analysis. Multivariate analysis revealed the expression of PARP1, γH2AX, and BRCA2 as independent poor prognostic indicators of OS and RFS. In addition, the combined expressional pattern of BRCA1, BRCA2, PARP1, and γH2AX (CSbbph) was an additional independent prognostic predictor for OS (P < .001) and RFS (P < .001). The 10-year OS rate was 95% in the CSbbph-low (CSbbph scores 0 and 1) subgroup, but that was only 35% in the CSbbph-high (CSbbph score 4) subgroup. CONCLUSION: This study has demonstrated that the individual and combined expression patterns of PARP1, γH2AX, BRCA1, and BRCA2 could be helpful in determining an accurate prognosis for BCA patients and for the selection of BCA patients who could potentially benefit from anti-PARP1 therapy with a combination of genotoxic chemotherapeutic agents. 相似文献
934.
Dong Geon Kim Younggeon Jin Juyoun Jin Heekyoung Yang Kyeung Min Joo Weon Sup Lee Sang Ryeol Shim Sung-Woo Kim Jinsang Yoo Sang Hoon Lee Jin-San Yoo Do-Hyun Nam 《MABS-AUSTIN》2015,7(6):1195-1204
Vascular endothelial growth factor (VEGF) and its receptors are considered the primary cause of tumor-induced angiogenesis. Specifically, VEGFR-2/kinase insert domain receptor (KDR) is part of the major signaling pathway that plays a significant role in tumor angiogenesis, which is associated with the development of various types of tumor and metastasis. In particular, KDR is involved in tumor angiogenesis as well as cancer cell growth and survival. In this study, we evaluated the therapeutic potential of TTAC-0001, a fully human antibody against VEGFR-2/KDR. To assess the efficacy of the antibody and pharmacokinetic (PK) relationship in vivo, we tested the potency of TTAC-0001 in glioblastoma and colorectal cancer xenograft models. Antitumor activity of TTAC-0001 in preclinical models correlated with tumor growth arrest, induction of tumor cell apoptosis, and inhibition of angiogenesis. We also evaluated the combination effect of TTAC-0001 with a chemotherapeutic agent in xenograft models. We were able to determine the relationship between PK and the efficacy of TTAC-0001 through in vivo single-dose PK study. Taken together, our data suggest that targeting VEGFR-2 with TTAC-0001 could be a promising approach for cancer treatment. 相似文献
935.
Dae Won Kim Sung Ho Lee Min Jea Shin Kibom Kim Sae Kwang Ku Jong Kyu Youn Su Bin Cho Jung Hwan Park Chi Hern Lee Ora Son Eun Jeong Sohn Sung-Woo Cho Jong Hoon Park Hyun Ah Kim Kyu Hyung Han Jinseu Park Won Sik Eum Soo Young Choi 《BMB reports》2015,48(11):618-623
FK506 binding protein 12 (FK506BP) is a small peptide with a single FK506BP domain that is involved in suppression of immune response and reactive oxygen species. FK506BP has emerged as a potential drug target for several inflammatory diseases. Here, we examined the protective effects of directly applied cell permeable FK506BP (PEP-1-FK506BP) on corneal alkali burn injury (CAI). In the cornea, there was a significant decrease in the number of cells expressing pro-inflammation, apoptotic, and angiogenic factors such as TNF-α, COX-2, and VEGF. Both corneal opacity and corneal neovascularization (CNV) were significantly decreased in the PEP-1-FK506BP treated group. Our results showed that PEP-1-FK506BP can significantly inhibit alkali burn-induced corneal inflammation in rats, possibly by accelerating corneal wound healing and by reducing the production of angiogenic factors and inflammatory cytokines. These results suggest that PEP-1-FK506BP may be a potential therapeutic agent for CAI. [BMB Reports 2015; 48(11): 618-623] 相似文献
936.
查尔酮合酶(chalcone synthase, CHS)是植物类黄酮化合物合成的关键酶,有关蕨类植物CHS基因的序列及功能信息尚不完善。本研究采用快速扩增cDNA末端(RACE)技术克隆获得了模式蕨类植物——水蕨(Ceratopteris thalictroides)CtCHS基因(GenBank登录号:JX027616.1),其cDNA序列全长为1616 bp,具有3个外显子和2个内含子,开放阅读框(ORF)为1215 bp,编码404个氨基酸。进化树分析表明,CtCHS与问荆(Equisetum arvense)、松叶蕨(Psilotum nudum)和3种薄囊蕨的查尔酮合成酶基因聚为一枝,说明这些蕨类植物亲缘关系较近且为单系起源。通过构建原核表达体系成功获得CtCHS蛋白的多克隆抗体并用于免疫印迹分析,结果表明CtCHS基因的表达明显受紫外光(UV)诱导。CtCHS基因的克隆与表达分析为进一步研究水蕨类黄酮化合物的合成及其调控机制提供了依据。 相似文献
937.
Effect of Bcl‐xL overexpression on sialylation of Fc‐fusion protein in recombinant Chinese hamster ovary cell cultures
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The sialic acid of glycoproteins secreted by recombinant Chinese hamster ovary (rCHO) cells can be impaired by sialidase under culture conditions which promote the extracellular accumulation of this enzyme. To investigate the effect of Bcl‐xL overexpression on the sialylation of glycoproteins produced in rCHO cell culture, two rCHO cell lines producing the same Fc‐fusion protein, which were derived from DUKX‐B11 and DG44, respectively, were engineered to have regulated Bcl‐xL overexpression using the Tet‐off system. For both cell lines, Bcl‐xL overexpression improved cell viability and extended culture longevity in batch cultures. As a result, a maximum Fc‐fusion protein titer increased by Bcl‐xL overexpression though the extent of titer enhancement differed between the two cell lines. With Bcl‐xL overexpression, the sialylation of Fc‐fusion protein, which was assessed by isoelectric focusing gel and sialic acid content analyses, decreased more slowly toward the end of batch cultures. This was because Bcl‐xL overexpression delayed the extracellular accumulation of sialidase activity by reducing cell lysis during batch cultures. Taken together, Bcl‐xL overexpression in rCHO cell culture increased Fc‐fusion protein production and also reduced the impairment of sialylation of Fc‐fusion protein by maintaining high viability during batch cultures. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1133–1136, 2015 相似文献
938.
不同温度条件下香水文心兰花香气的成分分析及感官评定 总被引:1,自引:0,他引:1
Flower aromatic components and their relative contents of Oncidium Sharry Baby ‘Sweet Fragrance ’ at full flowering stage under conditions of 10 ℃, 20 ℃ and 30 ℃ were analyzed by solid phase micro-extr... 相似文献
939.
Min Chen Wenjing Tang Lei Hou Ruozhuo Liu Zhao Dong Xun Han Xiaofei Zhang Dongjun Wan Shengyuan Yu 《PloS one》2015,10(6)
Background and Objective
Conflicting data have been reported on the association between tumor necrosis factor (TNF) –308G>A and nitric oxide synthase 3 (NOS3) +894G>T polymorphisms and migraine. We performed a meta-analysis of case-control studies to evaluate whether the TNF –308G>A and NOS3 +894G>T polymorphisms confer genetic susceptibility to migraine.Method
We performed an updated meta-analysis for TNF –308G>A and a meta-analysis for NOS3 +894G>T based on studies published up to July 2014. We calculated study specific odds ratios (OR) and 95% confidence intervals (95% CI) assuming allele contrast, dominant model, recessive model, and co-dominant model as pooled effect estimates.Results
Eleven studies in 6682 migraineurs and 22591 controls for TNF –308G>A and six studies in 1055 migraineurs and 877 controls for NOS3 +894G>T were included in the analysis. Neither indicated overall associations between gene polymorphisms and migraine risk. Subgroup analyses suggested that the “A” allele of the TNF –308G>A variant increases the risk of migraine among non-Caucasians (dominant model: pooled OR = 1.82; 95% CI 1.15 – 2.87). The risk of migraine with aura (MA) was increased among both Caucasians and non-Caucasians. Subgroup analyses suggested that the “T” allele of the NOS3 +894G>T variant increases the risk of migraine among non-Caucasians (co-dominant model: pooled OR = 2.10; 95% CI 1.14 – 3.88).Conclusions
Our findings appear to support the hypothesis that the TNF –308G>A polymorphism may act as a genetic susceptibility factor for migraine among non-Caucasians and that the NOS3 +894G>T polymorphism may modulate the risk of migraine among non-Caucasians. 相似文献940.
Yongsoo Park Hyunok Kim Leejin Park Dongsoo Min Jinseu Park Sooyoung Choi Moon Hyang Park 《PloS one》2015,10(6)