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91.
Rehan Ali Sandeep Apte Marta Vilalta Murugesan Subbarayan Zheng Miao Frederick T. Chin Edward E. Graves 《PloS one》2015,10(10)
We evaluated the relationship between pre-treatment positron emission tomography (PET) using the hypoxic tracer 18F-[2-(2-nitro-1-H-imidazol-1-yl)-N-(2,2,3,3,3- pentafluoropropyl) acetamide] (18F-EF5) and the response of preclinical tumor models to a range of fractionated radiotherapies. Subcutaneous HT29, A549 and RKO tumors grown in nude mice were imaged using 18F-EF5 positron emission tomography (PET) in order to characterize the extent and heterogeneity of hypoxia in these systems. Based on these results, 80 A549 tumors were subsequently grown and imaged using 18F-EF5 PET, and then treated with one, two, or four fraction radiation treatments to a total dose of 10–40 Gy. Response was monitored by serial caliper measurements of tumor volume. Longitudinal post-treatment 18F-EF5 PET imaging was performed on a subset of tumors. Terminal histologic analysis was performed to validate 18F-EF5 PET measures of hypoxia. EF5-positive tumors responded more poorly to low dose single fraction irradiation relative to EF5-negative tumors, however both groups responded similarly to larger single fraction doses. Irradiated tumors exhibited reduced 18F-EF5 uptake one month after treatment compared to control tumors. These findings indicate that pre- treatment 18F-EF5 PET can predict the response of tumors to single fraction radiation treatment. However, increasing the number of fractions delivered abrogates the difference in response between tumors with high and low EF5 uptake pre-treatment, in agreement with traditional radiobiology. 相似文献
92.
Guoyu Jia Fusheng Di Qipeng Wang Jinshuang Shao Lei Gao Lu Wang Qiang Li Nali Li 《PloS one》2015,10(11)
Background
Non-alcoholic fatty liver disease (NAFLD) is prevalent in individuals with type 2 diabetes mellitus (T2DM). Diabetic nephropathy (DN) is also associated with T2DM. However, little is known about the interaction between these conditions in patients with T2DM.Objective
To examine the association between NAFLD and DN in patients with T2DM.Methods
This retrospective study included patients seen between January 2006 and July 2014.T2DM patients were divided into two groups based on NAFLD status (with NAFLD = group A; without = group B). The cumulative incidence of DN and chronic kidney disease (CKD) staging were compared between the two groups. Liver fat content was examined in some patients. Associations among NAFLD, other factors,and DN were analyzed by the additive interaction method.Results
Cumulative incidence of DN in patients from group A (58.58%) was higher than in group B (37.22%) (P = 0.005). In both groups, the number of DN patients with CKD stage 1 was greater than the number of patients with stages 2–5. Increased liver fat content was associated with increased occurrence of severe and mild albuminuria and decreased glomerular filtration rate (GFR). There were positive correlations between NAFLD and insulin resistance index (HOMA-IR), free fatty acids (FFA), tumor necrosis factor-α (TNF-α), omentin-1, visceral fat area, homocysteine (HCY), and serum uric acid (UA).Conclusion
NAFLD might be a risk factor for DN. Elevated liver fat content could be associated with higher DN burden. 相似文献93.
94.
The average height of 31-aged Robinia pseudoacacia plantation in west mountain of Beijing is 7 in and the mean breastheight diameter of tree is 8.3 cm. The number of tree per hectare appears 1750. The canopy coverage of plantation shows 0.5. Using tile diameter square at tree breast height times tree height (D2H), as an independing variable, to estimate the dry weight of various parts of trees, between them the significient correlations occur. According to the modle of Wstem=58.88(D2H)0.88 (WBranch)=e7.77+0.001(D2H) (Wleaf)=e5.71+0.0008(D2H) (Wroot)=e7.67+0.0009(D2H) 28.45 t/ha of the stem biomass, 11.6 t/ha of the branch biomass. 0.97 t/ha of the leaf biomass, 7.6 t/ha of the root biomass are estimated in arbor layer. The aboveground and belowground biomass of shrub and herb layers axe 13.71 t/ha and 10.72 t/ha respectively in September, the biomass of shrub and herb layer is 24.43 t/ha. 73.05 t/ha of the total biomass in Robinia pseudoacacia plantation is obtained. 相似文献
95.
Wang W Liu X Zhao J Zhao B Zhang S Miao J 《Bioorganic & medicinal chemistry letters》2007,17(2):482-485
To understand the effects of a novel butyrolactone derivative, 3-benzyl-5-((2-nitrophenoxy) methyl)-dihydrofuran-2(3H)-one (3BDO), on the apoptosis of vascular endothelial cells (VECs), we exposed 3BDO (20-60 microg/ml) to VECs deprived of serum and FGF-2 for 24 and 48 h, respectively. The results showed that 3BDO (20-60 microg/ml) increased VEC viability and inhibited VEC apoptosis induced by deprivation of serum and FGF-2 in a very weak dose-dependent manner. During this process, integrin beta4 expression was depressed, but the level of reactive oxygen species (ROS) was not changed. The data suggested that 3BDO (20-60 microg/ml) could inhibit VEC apoptosis and suppress integrin beta4 expression, but it could not depress the ROS level induced by deprivation of serum and FGF-2. 相似文献
96.
Aluminium resistance requires resistance to acid stress: a case study with spinach that exudes oxalate rapidly when exposed to Al stress 总被引:3,自引:0,他引:3
Spinach is a vegetable with a high oxalate concentration in its tissues. Oxalate efflux from spinach (Spinacia oleracea L. cv. Quanneng) roots was rapidly stimulated (within 30 min) by aluminium (Al) treatment. The efflux was constant within 6 h, but increased with increasing Al concentration. The efflux was confined to the root tip (0-5 mm), which showed a 5-fold greater efflux than the root zone distal to the tip (5-10 mm). Oxalate efflux could not be triggered by treatment with the trivalent cation lanthanum or by phosphorus deficiency, indicating that the efflux was specific to the Al treatment. All this evidence suggested that spinach possesses Al-resistance mechanisms. However, spinach was found to be as sensitive to Al toxicity as the Al-sensitive wheat line ES8, which had no Al-dependent organic acids efflux. The Al accumulated in the apical 5 mm of the roots of spinach which was also similar to that in the Al-sensitive wheat after 24 h treatment with 50 microM AlCl(3), indicating a non-exclusion mechanism. In addition, root elongation in spinach was significantly inhibited at pH 4.5, compared with that at pH 6.5. Based on this evidence, it is concluded that the sensitivity to acid stress in spinach could mask the potential role for oxalate to protect the plant roots from Al toxicity. 相似文献
97.
In pharmaceutical sciences, a crucial step of the drug discovery process is the identification of drug-target interactions. However, only a small portion of the drug-target interactions have been experimentally validated, as the experimental validation is laborious and costly. To improve the drug discovery efficiency, there is a great need for the development of accurate computational approaches that can predict potential drug-target interactions to direct the experimental verification. In this paper, we propose a novel drug-target interaction prediction algorithm, namely neighborhood regularized logistic matrix factorization (NRLMF). Specifically, the proposed NRLMF method focuses on modeling the probability that a drug would interact with a target by logistic matrix factorization, where the properties of drugs and targets are represented by drug-specific and target-specific latent vectors, respectively. Moreover, NRLMF assigns higher importance levels to positive observations (i.e., the observed interacting drug-target pairs) than negative observations (i.e., the unknown pairs). Because the positive observations are already experimentally verified, they are usually more trustworthy. Furthermore, the local structure of the drug-target interaction data has also been exploited via neighborhood regularization to achieve better prediction accuracy. We conducted extensive experiments over four benchmark datasets, and NRLMF demonstrated its effectiveness compared with five state-of-the-art approaches. 相似文献
98.
Qing-Song Shao Qiao-Sheng Guo Yan-Ming Deng Hai-Peng Guo 《Biochemical Systematics and Ecology》2010,38(6):1160-1169
The diversity and genetic relationship among 29 populations of Chrysanthemum morifolium, one of Chrysanthemum indicum and one of Chrysanthemum nankingense from China were analyzed using morphological traits and molecular markers. Twenty morphological traits were scored as well as 182 ISSR marker-fragments, as amplified by 22 primers [the percentage of polymorphic bands (PPB): 81.87%], and 243 SRAP marker-fragments as generated by 26 primer pairs (PPB: 75.72%). Mantel’s test indicated significant correlation (r = 0.624) of morphological trait and SRAP. By contrast, the morphological trait showed low correlation with ISSR (r = 0.246). Cluster analysis showed groupings of the accessions according to all four methods correlated well with their geographic region of origin, and most populations from the south of China were classified into one cluster and most populations from the north of China were classified into another cluster. Finally, an appropriate strategy for conserving the C. morifolium germplasm was proposed. 相似文献
99.
Wang ZJ Zhou YJ Zhao YX Liu YY Shi DM Liu XL Yu M Gao F 《Obesity (Silver Spring, Md.)》2012,20(1):141-146
Obesity is a major risk factor for developing coronary artery disease. The impact of obesity on prognosis among those with established coronary disease is less clear. The objective of this study was to evaluate the effect of obesity on repeat revascularization in patients undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DES). We examined 6,083 patients who were divided into three groups according to BMI: normal (BMI 18.5-24.9 kg/m(2), n = 1,592); overweight (BMI 25-29.9 kg/m(2), n = 3,026) and obese (BMI >30 kg/m(2), n = 1,465). The follow-up focused on clinical-driven repeat revascularization, including target lesion revascularization (TLR) and nonTLR. Median follow-up was 26 months (interquartile range 20-32). There was no significant difference in the incidence of TLR among normal, overweight, and obese patients (6.3% vs. 6.1% vs. 7.1%; P = 0.423). In contrast, the incidence of nonTLR was significantly higher in obese patients compared with normal and overweight (8.4% vs. 6.0% vs. 5.8%, P = 0.003). Multivariate analysis showed that obesity was an independent predictor of nonTLR during follow-up (hazard ratio = 1.39; 95% confidence interval = 1.06-1.83; P = 0.019), along with diabetes and hypercholesterolemia. Concomitant use of statins was independently associated with decreased risk of nonTLR (hazard ratio = 0.75; 95% confidence interval = 0.62-0.92; P = 0.005). In conclusion, among patients undergoing PCI with DES, obesity was not associated with TLR, but was associated with a higher risk of nonTLR. 相似文献
100.