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991.
K Nam  HY Nam  PH Kim  SW Kim 《Biomaterials》2012,33(32):8122-8130
We developed a paclitaxel-conjugated polymeric micelle, ABP-PEG(3.5k)-Paclitaxel (APP) consisting of poly (ethylene glycol) (PEG) and arginine-grafted poly (cystaminebisacrylamide-diaminohexane) (ABP) for the co-delivery of gene and drug. The APP polymer self-assembled into cationic polymeric micelles with a critical micelle concentration (CMC) value of approximately 0.062?mg/mL, which was determined from measurements of the UV absorption of pyrene. The micelles have an average size of about 3?nm and a zeta potential of about?+14?mV. Due to the positive surface charge, APP micelles formed polyplexes with plasmid DNA approximately 200?nm in diameter. The luciferase gene and mouse interleukin-12 (IL-12) gene was used to monitor gene delivery potency. APP polyplexes showed increased gene delivery efficiency and cellular uptake with higher anticancer potency than paclitaxel alone. These results demonstrate that an APP micelle-based delivery system is well suitable for the co-delivery of gene and drug.  相似文献   
992.
Objective: We assessed the serum glucagon-like peptide-1 (GLP-1) levels for Chinese adults with pre-diabetes (PD) and newly-diagnosed diabetes mellitus (NDDM) during oral glucose tolerance test (OGTT). The relationships between total GLP-1 level and islet β cell function, insulin resistance (IR) and insulin sensitivity (IS) were also investigated.Methods: A 75g glucose OGTT was given to 531 subjects. Based on the results, they were divided into groups of normal glucose tolerance (NGT), isolated impaired fasting glucose (IFG), isolated impaired glucose tolerance (IGT), IFG combined IGT (IFG+IGT) and NDDM. Total GLP-1 levels were measured at 0- and 2-hour during OGTT. Homeostasis model assessment of β cell function (HOMA-β), HOMA of insulin resistance (HOMA-IR), Gutt and Matsuda indexes were calculated. The relationships between GLP-1 level and β cell function, IR and IS were analyzed.Results: The levels of total fasting GLP-1 (FGLP-1), 2h GLP-1 (2hGLP-1) and 2hGLP-1 increments (∆GLP-1) following OGTT reduced significantly in IFG+IGT and NDDM groups (P<0.005). HOMA-β , HOMA-IR, Gutt and Matsuda indexes demonstrated various patterns among NGT, isolated IFG, isolated IGT, IFG+IGT and NDDM groups (P<0.05). Spearman rank correlation analysis and multivariable linear regression model suggested that some levels of correlation between GLP-1 levels, ∆GLP-1 and β cell function, IR (P<0.05).Conclusions: The total GLP-1 levels and its response to glucose load decreased significantly in IFG+IGT group, compared to isolated IFG or IGT group. They were even similar to that of NDDM group. Moreover, there were observable correlations between impaired GLP-1 secretion and β cell function, IR and IS.  相似文献   
993.
Previous studies showed the relationship between fatty acids and the risk of developing Alzheimer's disease (AD). However, they did not address potential differences in free fatty acid (FFA) profiles that could be used to distinguish between AD patients and healthy controls. In the present study we used gas chromatography-mass spectrometry (GC-MS) technology coupled with multivariate statistical analysis to study profiles of FFA in AD. The results indicated 2 saturated fatty acids (C14:0 and C16:0; p < 0.001 and p < 0.05, respectively), 3 unsaturated fatty acids (C18:1, C18:3, and C22:6; p < 0.05, p < 0.05, and p < 0.001, respectively), where mean levels in serum from AD patients were significantly lower than controls. Partial least squares discriminant analysis (PLS-DA) models with unit variance (UV) scaling and orthogonal signal correction (OSC) data preprocessing methods were employed to refine intergroup differences between FFA profiles. The results of the analysis have highlighted docosahexaenoic acid (DHA) as the FFA with the greatest potential as a biomarker of AD, and this study has demonstrated that FFA biomarkers have considerable potential in diagnosing and monitoring AD.  相似文献   
994.
低温抽提Jurkat细胞膜去污剂抗性的膜成分(DIG),检测Src家族酪氨酸激酶(PTK)及衰变加速因子(DAF)的分布情况。共聚焦扫描显微技术检测Jurkat细胞静息与交联状态下DAF分子对去污剂Triton-X100的抗溶性,以探讨其在Jur-kat细胞免疫识别中的作用,结果显示静息状态CD3对去污剂无抗溶性,而DAF与Lck有抗溶性。单抗交联后CD3对去污剂抗性有所增加。静息状态DAF与Src家族PTK特异分布于膜微区中,交联CD3可诱导CD3与膜微区特异性聚集,DAF所在的膜微区可能促进T细胞的免疫识别和信号传递作用。  相似文献   
995.
Demineralized bone matrix (DBM) powder is widely used for bone regeneration due to its osteoinductivity and osteoconductivity. However, difficulties with handling, its tendency to migrate from graft sites, and lack of stability after surgery can sometimes limit the clinical utility of this material. In this work, the possibility of using a thermogelling chitosan carrier to deliver DBM powder was assessed. The DBM-thermogelling putty improved handling and formed a gel-like composite in situ at body temperature within a clinically relevant time period. The properties of the formed composite, including morphology, porosity, mechanical properties, equilibrium swelling as well as degradability, are significantly influenced by the ratio of DBM to thermogelling chitosan. The in vitro study showed that the alkaline phosphatase activity of C2C12 cells encapsulated in the composite was steadily increased with culture time. The in vivo study showed that increased DBM content in the DBM-thermogelling chitosan induced ectopic bone formation in a nude rat model. The diffusion of growth factor from the DBM-thermogelling chitosan as well as the host-implant interactions are discussed.  相似文献   
996.
The genetic risk factors for chronic obstructive pulmonary disease (COPD) are still largely unknown. To date, genome-wide association studies (GWASs) of limited size have identified several novel risk loci for COPD at CHRNA3/CHRNA5/IREB2, HHIP and FAM13A; additional loci may be identified through larger studies. We performed a GWAS using a total of 3499 cases and 1922 control subjects from four cohorts: the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE); the Normative Aging Study (NAS) and National Emphysema Treatment Trial (NETT); Bergen, Norway (GenKOLS); and the COPDGene study. Genotyping was performed on Illumina platforms with additional markers imputed using 1000 Genomes data; results were summarized using fixed-effect meta-analysis. We identified a new genome-wide significant locus on chromosome 19q13 (rs7937, OR = 0.74, P = 2.9 × 10(-9)). Genotyping this single nucleotide polymorphism (SNP) and another nearby SNP in linkage disequilibrium (rs2604894) in 2859 subjects from the family-based International COPD Genetics Network study (ICGN) demonstrated supportive evidence for association for COPD (P = 0.28 and 0.11 for rs7937 and rs2604894), pre-bronchodilator FEV(1) (P = 0.08 and 0.04) and severe (GOLD 3&4) COPD (P = 0.09 and 0.017). This region includes RAB4B, EGLN2, MIA and CYP2A6, and has previously been identified in association with cigarette smoking behavior.  相似文献   
997.
998.
We examined the association between single-nucleotide polymorphisms (SNPs) previously associated with chronic obstructive pulmonary disease (COPD) and/or lung function with COPD and COPD-related phenotypes in a novel cohort of patients with severe to very severe COPD. We examined 315 cases of COPD and 330 Caucasian control smokers from Poland. We included three SNPs previously associated with COPD: rs7671167 (FAM13A), rs13180 (IREB2), and rs8034191 (CHRNA 3/5), and four SNPs associated with lung function in a genome-wide association study of general population samples: rs2070600 (AGER), rs11134242 (ADCY2), rs4316710 (THSD4), and rs17096090 (INTS12). We tested for associations with severe COPD and COPD-related phenotypes, including lung function, smoking behavior, and body mass index. Subjects with COPD were older (average age 62 versus 58 years, P < 0.01), with more pack-years of smoking (45 versus 33 pack-years, P < 0.01). CHRNA3/5 (odds ratio [OR], 1.89; 95% confidence interval [CI], 1.5-2.4; P = 7.4 × 10(-7)), IREB2 (OR, 0.69; 95% CI, 0.5-0.9; P = 3.4 × 10(-3)), and ADCY2 (OR, 1.35; 95% CI, 1.1-1.7; P = 0.01) demonstrated significant associations with COPD. FAM13A (OR, 0.8; 95% CI, 0.7-1.0; P = 0.11) approached statistical significance. FAM13A and ADCY2 also demonstrated a significant association with lung function. Thus, in severe to very severe COPD, we demonstrate a replication of association between two SNPs previously associated with COPD (CHRNA3/5 and IREB2), as well as an association with COPD of one locus initially associated with lung function (ADCY2).  相似文献   
999.
Park SJ  Lee KS  Kim SR  Chae HJ  Yoo WH  Kim DI  Jeon MS  Lee YC 《Inflammation research》2012,61(10):1069-1083

Background

Occupational asthma is characterized by airway inflammation and hyperresponsiveness associated with increased vascular permeability. AMP-activated protein kinase (AMPK) has been suggested to be a novel signaling molecule modulating inflammatory responses.

Objective

We sought to evaluate the involvement of AMPK in pathogenesis of occupational asthma and more specifically investigate the effect and molecular mechanisms of AMPK activation in regulating vascular permeability.

Methods

The mechanisms of action and therapeutic potential of an AMPK activator, 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) were tested in a murine model of toluene diisocyanate (TDI)-induced asthma.

Results

AICAR attenuated airway inflammation and hyperresponsiveness increased by TDI inhalation. Moreover, TDI-induced increases in levels of hypoxia-inducible factor (HIF)-1α, HIF-2α, vascular endothelial growth factor A (VEGFA), and plasma exudation were substantially decreased by treatment with AICAR. Our results also showed that VEGFA expression was remarkably reduced by inhibition of HIF-1α and HIF-2α with 2-methoxyestradiol (2ME2) and that an inhibitor of VEGFA activity, CBO-P11 as well as 2ME2 significantly suppressed vascular permeability, airway infiltration of inflammatory cells, and airway hyperresponsiveness induced by TDI. In addition, AICAR reduced reactive oxygen species (ROS) generation and levels of malondialdehyde and T-helper type 2 cytokines (IL-4, IL-5, and IL-13), while this agent enhanced expression of an anti-inflammatory cytokine, IL-10.

Conclusions

These results suggest that AMPK activation ameliorates airway inflammatory responses by reducing vascular permeability via HIF/VEGFA pathway as well as by inhibiting ROS production and thus may be a possible therapeutic strategy for TDI-induced asthma and other airway inflammatory diseases.  相似文献   
1000.
背景:Claudin-1是一种多功能蛋白,除了组成紧密连接封闭细胞间隙,它在转录水平的表达失调可能作为一种分子标志反映到恶性肿瘤的侵袭转移和预后中。 目的:构建重组大鼠重组Claudin-1萤光素酶报告基因质粒。 方法:设计和合成包含5’非转录区的约2 000 bp的脱氧核糖核酸链,经过限制性内切酶KpnⅠ和MluⅠ酶切后插入到pGL3-Basic载体中,并用感受态E.coli DH5α和Pmd18-T-simple载体筛选阳性样品。阳性克隆通过测序和PCR证实。实验分为4组:对照组,阳性对照组(pGL3-promoter质粒转染),阴性对照组(转染pGL3-Basic质粒),实验组(转染pGL3-Claudin-1 promoter质粒)。将质粒转染293T细胞检测Claudin-1启动子活性。 结果与结论:重组质粒DNA测序结果采用NCBI blast比对与GenBank(gi|62750811)中大鼠Claudin-1基因启动子序列完全匹配。重组萤光素酶报告基因转录活性检测与pGL3-Basic质粒相比,重组pGL3质粒转录活性明显增强 (P < 0.001)。经过测序和转染结果证实有效的pGL3-Claudin-1启动子质粒构建成功。  相似文献   
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