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931.
Chung-Yung Jetty Lee Helen B. Isaac Shan Hong Huang Lee Hua Long Huansong Wang Jan Gruber 《Free radical research》2013,47(6):622-628
This study investigated the effect of a single dose of tomato sauce on healthy male volunteers in a randomized crossover study. Healthy male subjects (n = 10) were enrolled. Placebo (rice and olive oil) or tomato (tomato sauce, rice and olive oil) meals were provided to the volunteers. Blood and urine samples were taken before consumption of meal (0 h) and 2, 4, 6, 24 and 48 h after meal. Consumption of tomato sauce increased plasma lycopene level by 5–22%, with a maximum level at 24 h (p<0.01) after the meal. Levels of plasma F2-isoprostanes, hydroxyeicosatetraenoic acid products, allantoin and urinary 8-hydroxy-2′-deoxyguanosine did not change after either meal, but urinary F2-isoprostanes (p<0.05) significantly decreased at 48 h compared to 0 h after the tomato sauce meal. This study showed that a single dose of tomato sauce meal had only a limited antioxidant effect in vivo. 相似文献
932.
Striking differences in the prevalence of coal workers' pneumoconiosis (CWP) exist between different coal mine regions. The major factors responsible for the observed regional differences in CWP have not yet been identified. In the present study, chemical reactivity of the carbon-centered free radicals in coals and lung tissues, as well as ferrous iron in the coals, were studied by ESR techniques. The ESR spectra clearly demonstrated the presence of at least two types of carbon-centered free radical species, which might respectively attribute to the macromolecular phase and the molecular phase of coal. Grinding produced free radicals in coals. Exposure of freshly ground coal to air for 28 h induced a slight increase of free radicals for most of the coals, and a slight decrease after 4 months' exposure. The lung tissue samples of coal workers deceased of CWP showed similar ESR spectra as coal samples, and these radicals were highly stable in the lung. After incubation of coals with glutathione, hydrogen peroxide, sodium formate or oxygen, the coal sample from the Gardanne mine which has never induced CWP, and thus is the least hazardous coal, showed the most significant change in the carbon-centered free radical concentration. No significant changes were observed among other coals reported to induce CWP. On the other hand, we found that the coals released different amounts of Fe2+ in an acidic medium. Interestingly, the prevalence of CWP correlates positively with the released Fe2+ content in these coals and with the amount of oxygen radicals produced by the interaction of Fe2+ with O2 in the acidified coal filtrates. Our studies indicate that the carbon-centered free radicals may not be biologically relevant to coal dust-induced pneumoconiosis, whereas the acid soluble Fe2+, which may be dissolved in the phagolysosomes of macrophages, can then lead to Fe2+-induced oxidative stress and eventual CWP development. 相似文献
933.
Xi Huang Jisen Dai Chuanshu Huang Qi Zhang Opinder Bhanot Edward Pelle 《Free radical research》2013,47(10):1135-1142
Deferoxamine (DFO) is a drug widely used for iron overload treatment to reduce body iron burden. In the present study, it was shown in mouse epidermal JB6 cells that all iron compounds transiently induced extracellular signal-regulated kinases (ERK) phosphorylation, whereas DFO further enhanced ERK phosphorylation over long periods. The ERK phosphorylation by DFO treatment appears to be due to the inhibition of MAPK phosphatases (MKP) by DFO. The combined effects of iron-initiated MAPK activation and DFO-mediated MKP inhibition resulted in a synergistic enhancement on AP-1 activities. The results indicate that the interplay between MAPK and MKP is important in regulating the extent of AP-1 activation. It is known that administration of DFO in iron overload patients often results in allergic responses at the injection sites. The results suggest that this synergistic AP-1 activation might play a role in DFO-induced skin immune responses of iron overload patients. 相似文献
934.
Qiang Fu Wen Lu Yi-jie Huang Qiang Wu Lin-guang Wang Hai-bo Wang Shu-zhong Jiang Yan-jiong Wang 《Cell biochemistry and biophysics》2013,67(3):911-914
The present study evaluated the efficacy of intracoronary administration of verapamil to attenuate the no-reflow phenomenon following the primary percutaneous coronary intervention (PCI) in patients with the ST-segment elevation acute myocardial infarction (STEMI). A total of 201 patients with STEMI who underwent primary PCI within 12 h from the beginning of the heart attack were included. The no-reflow phenomenon was defined as substantial coronary anterograde flow of TIMI ≤2. Verapamil (100–200 μg) was injected into coronary artery immediately after no-reflow; the coronary arteriography was repeated later. Hundred and ninety-eight patients with STEMI successfully underwent primary PCI, and 246 stents were implanted with the average of 1.2 stents per patient. No-reflow occurred in 25 out of 198 patients (12.6 %). Twenty-one (84 %) patients developed the flow of TIMI ≥3 after intracoronary administration of verapamil, as revealed by repeated coronary angiography. Two patients developed transient hypotension which normalized without treatment within 3–5 min. Three patients showed sinus bradycardia, in one patient there was transient II sinoatrial block, and one patient developed type 1 atrioventricular block. All adverse effects were alleviated after intravenous injection of atropine (0.5–1 mg). In conclusion, the no-reflow phenomenon following primary PCI in patients with STEMI is significantly improved by intracoronary administration of verapamil which is useful to reduce cardiovascular events during operation. 相似文献
935.
Wang Ting Qian Yanyan Huang Jian Hua Keqin Ma Duan 《Cell biochemistry and biophysics》2013,67(3):1041-1047
We sought to investigate the relationship between the changes of CpG island methylation status of LMNA gene and insulin resistance in polycystic ovary syndrome (PCOS) patients. The genome-wide methylation microarray screening was done in three PCOS cases of insulin resistance and one case of a normal woman. The PCOS insulin resistance-related genes were identified as indicated by the results of gene chip screening. Then, 24 cases of insulin-resistant PCOS patients and 24 cases of normal individuals were studied to identify the effects of the candidate genes using genome-wide study of DNA from the peripheral blood analyzed by MassARRAY®EpiTYPER? DNA methylation analysis technique. We found that the methylation status of CpG island in the promoter area of LMNA gene was changed. The 20 CG sites in CpG island of LMNA gene were examined using case control experiment among which 12 CpG sites differed significantly (P < 0.05) between two groups while the remaining eight CpG sites differed non-significantly. We, therefore, concluded that the changes in the hypermethylation status of CpG island of LMNA gene were related to the insulin resistance in PCOS patients, indicating that this gene may be involved in the regulation of PCOS-associated insulin resistance. 相似文献
936.
Yi-Ming Zhang Jing Ruan Rong Xiao Qiong Zhang Yue-Sheng Huang 《Cell biochemistry and biophysics》2013,67(3):1005-1014
Infrared lasers are widely used in medicine, industry, and other fields. While science, medicine, and the society in general have benefited from the many practical uses of lasers, they also have inherent safety issues. Although several procedures have been put forward to protect the skin from non-specific laser-induced damage, individuals receiving laser therapy or researchers who use laser are still at risk for skin damage. This study aims to understand the interaction between laser and the skin, and to investigate the differences between the skin damage caused by 1,064-nm laser and common thermal burns. Skin lesions on Wistar rats were induced by a 1,064-nm CW laser at a maximum output of 40 W and by a copper brass bar attached to an HQ soldering iron. Histological sections of the lesions and the process of wound healing were evaluated. The widths of the epidermal necrosis and dermal denaturalization of each lesion were measured. To observe wound healing, the epithelial gap and wound gap were measured. Masson’s trichrome and picrosirius red staining were also used to assess lesions and wound healing. The thermal damage induced by laser intensified significantly in both horizontal dimension and in vertical depth with increased duration of irradiation. Ten days after wounding, the dermal injuries induced by laser were more severe. Compared with the laser-induced skin damage, the skin burn induced by an HQ soldering iron did not show a similar development or increased in severity with the passage of time. The results of this study showed the pattern of skin damage induced by laser irradiation and a heated brass bar. This study also highlighted the difference between laser irradiation and thermal burn in terms of skin damage and wound healing, and offers insight for further treatment. 相似文献
937.
Seth J. Schwartz Erin Phelps Jacqueline V. Lerner Shi Huang C. Hendricks Brown Selva Lewin-Bizan 《应用发育科学》2013,17(4):197-211
The present study was designed to examine the association of positive youth development with the likelihood of tobacco, alcohol, marijuana, hard drug, and sex initiation between 5th and 10th grades. A national, largely middle-class sample of 5,305 adolescents, participating in a longitudinal study funded by the National 4-H Council (although not all participants were enrolled in 4-H or other after-school programs), completed measures of positive youth development (PYD) constructs and of tobacco, alcohol, marijuana, and hard drug use once per year between 5th and 10th grades. At the 9th and 10th grade assessments, adolescents were asked whether they had initiated sexual intercourse and, if so, at what age they had first engaged in intercourse. Although the present sample was somewhat lower risk compared to national averages, survival analysis models indicated that PYD was significantly and negatively associated with the initiation hazards for tobacco use, marijuana use, and sex initiation for girls only, and with hard drug use for both genders. PYD was also positively associated with the odds of condom use across genders. Results are discussed with regard to PYD as a preventive process. 相似文献
938.
939.
Chuying Ma Guangfu Yin Danhong Yan Xueling He Li Zhang Yan Wei Zhongbing Huang 《Journal of peptide science》2013,19(12):730-736
Discovery of peptide ligands that can target human ovarian cancer and deliver chemotherapeutics offers new opportunity for cancer therapy. The advent of phage‐displayed peptide library facilitated the screening of such peptides. In vivo screening that set in a microanatomic and functional context was applied in our study, and a novel peptide WSGPGVWGASVK targeting ovarian cancer was isolated. The phage clone PC3‐1 displaying peptide WSGPGVWGASVK can gain effective access to accumulate in the tumor sites after intravenous injection while reducing its accumulation in normal organs. Positive immunostaining of PC3‐1 was located in both sites of tumor cells and tumor blood vessels, which resulted in a diffuse binding pattern through the tumor. In vitro study results confirmed the capability of peptide WSGPGVWGASVK binding to and being internalized by both tumor cells and angiogenic endothelial cells. Flow cytometry analysis revealed that the peptide bound to SKOV3 cells with Kd value of 5.43 ± 0.4 μM. Taken together, it suggested that peptide WSGPGVWGASVK is a lead candidate for delivering therapeutics to penetrate into tumors. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
940.
Li Tang Xiaoyan Feng Feng He Rui Huang Jing He Bingshui Xiu Kun Chen Xiqin Yang Shigan Ling Heqiu Zhang 《Molecular biotechnology》2013,54(1):58-67
In order to overcome the instability of CpG ODN in vivo, sequence diversity, and individual differences, eleven CpG ODN fragments were meticulously selected and linked to form a Multi-CpG, which were repeatedly inserted into the cloning vector pUC19 for constructing the recombinant plasmid pUCpGs10 containing ten of Multi-CpG. Using the multi-genotype HCV E1 and multi-epitope complex HCV-T as immunogens, and plasmid pUCpGs10 as the immune adjuvant, Balb/c mice were immunized through nasal and subcutaneous immunization. Strong-specific humoral and cellular immune response were induced, which can obviously inhibit the growth of homograft expressing HCV antigen. The immune adjuvant effect of pUCpGs10 closely matched that of Freund’s complete adjuvant. The plasmid pUCpGs10 can significantly improve IgA content in serum and different mucosal extract and systematical T-cell response via intranasal immunization. In conclusions, the newly constructed immunostimulatory plasmid pUCpGs10 is able to effectively activate the humoral and cellular immune activity, and possesses activation on mucosal immune response. 相似文献