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ABSTRACT: Combined pollution of selenium (Se) and mercury (Hg) has been known in Wanshan district (Guizhou Province, China). A better understanding of how Se and Hg interact in plants and the phytotoxicity thereof will provide clues about how to avoid or mitigate adverse effects of Se/Hg on local agriculture. In this study, the biological activity of Se has been investigated in garlic with or without Hg exposure. Se alone can promote garlic growth at low levels (<0.1 mg L(-1)), whereas it inhibits garlic growth at high levels (>1 mg L(-1)). The promotive effect of Se in garlic can be enhanced by low Hg exposure (<0.1 mg L(-1)). When both Se and Hg are at high levels, there is a general antagonistic effect between these two elements in terms of phytotoxicity. Inductively coupled plasma mass spectrometry (ICP-MS) data suggest that Se is mainly concentrated in garlic roots, compared to the leaves and the bulbs. Se uptake by garlic in low Se medium (<0.1 mg L(-1)) can be significantly enhanced as Hg exposure levels increase (P < 0.05), while it can be inhibited by Hg when Se exposure levels exceed 1 mg L(-1). The synchrotron radiation X-ray fluorescence (SRXRF) mapping further shows that Se is mainly concentrated in the stele of the roots, bulbs and the veins of the leaves, and Se accumulation in garlic can be reduced by Hg. The X-ray absorption near edge structure (XANES) study indicates that Se is mainly formed in C-Se-C form in garlic. Hg can decrease the content of inorganic Se mainly in SeO3(2-) form in garlic while increasing the content of organic Se mainly in C-Se-C form (MeSeCys and its derivatives). Hg-mediated changes in Se species along with reduced Se accumulation in garlic may account for the protective effect of Hg against Se phytotoxicity.
Metallomics 06/2013; · 3.90 Impact Factor
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ABSTRACT: To investigate the influence of selenium on mercury phytotoxicity, the levels of selenium and mercury were analyzed with inductively coupled plasma-mass spectrometry (ICP-MS) in garlic tissues upon exposure to different dosages of inorganic mercury (Hg(2+)) and selenite (SeO3(2-)) or selenate (SeO4(2-)). The distributions of selenium and mercury were examined with micro-synchrotron radiation X-ray fluorescence (μ-SRXRF), and the mercury speciation was investigated with micro-X-ray absorption near edge structure (μ-XANES). The results show that Se at higher exposure levels (>1mg/L of SeO3(2-) or SeO4(2-)) would significantly inhibit the absorption and transportation of Hg when Hg(2+) levels are higher than 1mg/L in culture media. SeO3(2-) and SeO4(2-) were found to be equally effective in reducing Hg accumulation in garlic. The inhibition of Hg uptake by Se correlates well with the influence of Se on Hg phytotoxicity as indicated by the growth inhibition factor. Elemental imaging using μ-SRXRF also shows that Se could inhibit the accumulation and translocation of Hg in garlic. μ-XANES analysis shows that Hg is mainly present in the forms of Hg-S bonding as Hg(GSH)2 and Hg(Met)2. Se exposure elicited decrease of Hg-S bonding in the form of Hg(GSH)2, together with Se-mediated alteration of Hg absorption, transportation and accumulation, may account for attenuated Hg phytotoxicity by Se in garlic.
Environmental Research 04/2013; · 3.40 Impact Factor
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ABSTRACT: Due to a long history of extensive mercury mining and smelting activities, local residents in Wanshan, China, are suffering from elevated mercury exposure. The objective of the present study was to study the effects of oral supplementation with selenium-enriched yeast in these long-term mercury-exposed populations. One hundred and three volunteers from Wanshan area were recruited and 53 of them were supplemented with 100 μg of organic selenium daily as selenium-enriched yeast while 50 of them were supplemented with the nonselenium-enriched yeast for 3 months. The effects of selenium supplementation on urinary mercury, selenium, and oxidative stress-related biomarkers including malondialdehyde and 8-hydroxy-2-deoxyguanosine were assessed. This 3-month selenium supplementation trial indicated that organic selenium supplementation could increase mercury excretion and decrease urinary malondialdehyde and 8-hydroxy-2-deoxyguanosine levels in local residents.
Environmental Science & Technology 10/2012; 46(20):11313-8. · 4.80 Impact Factor
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ABSTRACT: Commercially available carbon nanotubes (CNT) often contain some quantities of metallic and carbonaceous impurities. These impurities influence their physicochemical properties and performance, and accordingly a number of potential applications. The lack of information of metal impurities may also preclude accurate environmental and health risk assessments for specific CNT materials. To address these needs, a quantitative analysis of the metal contents has been made in a number of commercial carbon nanotubes produced by different manufacturers. More than 20 metals or metalloids were determined by neutron activation analysis. The results indicate arranging from 0.44 to 3 wt% of catalyst residues remained although the producers claim to provide a catalyst-free product. Most of the impurity elements are transition metals, such as Fe, Ni, Mo, Y, Co and Cr. In addition to the expected catalyst residues, other unexpected impurity elements were detected including As, Gd, W, Yb, Sm and so on. Metallic impurities in carbon nanotube materials should come from the large-scale production procedures, post fabrication and post-purification treatments. The analytical results determined by inductively-coupled plasma mass spectrometry show that a further deep purification using conventional acid reflux cannot completely remove the metallic impurities from carbon nanotubes. Post-production clean up is difficult and often incompletely.
Journal of Nanoscience and Nanotechnology 03/2011; 11(3):2389-97. · 1.56 Impact Factor
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ABSTRACT: Endohedral metallofullerenes have unique chemical and physical properties that are essential for biomedical applications. They can be used as a radiotracer in magnetic resonance and X-ray imaging (MRI and XRI). Polyhydroxylated metallofullerene Gd@C82(OH)x has been studied as a new high efficient contrast agents for MRI and has also shown high efficiency for antitumor growth. Previous studies have shown that Gd@C82(OH)22 mainly accumulated in bone, pancreas, liver and kidney after intraperitoneal administration. However, whether the nanoparticles can enter into cells and the site of their potential action remains unclear. In this work, the distribution patterns of Gd@C82(OH)22 in subcellular compartments were studied using the techniques of differential centrifugation and ICP-MS analysis. The results indicate that the Gd@C82(OH)22 can enter into cells and the subcellular distribution patterns are significantly different from that of GdCl3. GdCl3 has much higher bioavailability for mice than Gd@C82(OH)22. Therefore, the present data suggest that Gd@C82(OH)22 in living systems may be not decomposed to release free Gd3+ ion and may be metabolized as a pristine carbon cage.
Journal of Nanoscience and Nanotechnology 12/2010; 10(12):8597-602. · 1.56 Impact Factor
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Fang Jiao,
Ying Qu,
Guoqiang Zhou,
Ying Liu,
Wei Li,
Cuicui Ge,
Yufeng Li,
Wei Hu,
Bai Li, Yuxi Gao,
Chunying Chen
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ABSTRACT: Oxidative stress is considered to be one of the important mechanisms involved in carcinogenesis. To investigate the effect of [Gd@C82(OH)22]n and [C60(OH)20]n nanoparticles on the oxidative stress in the tumor-bearing mice, several antioxidative enzymes and antioxidants were tested for mice with or without tumor inoculation. Transplanted tumors were grown in mice by subcutaneous inoculation of a metastatic Lewis lung carcinoma in female C57/BL mice. More importantly, the tumor cells can metastasize into the normal lung tissues gradually. Therefore, in present paper, the activities of copper-zinc superoxide dismutase (CuZn-SOD), glutathione peroxidase (GSH-Px), glutathione S-transferase (GST), as well as the levels of reduced glutathione (GSH) and malondialdehyde (MDA) in the tumor-invaded lung tissues of the tumor-bearing mice were compared to the nomal lung tissues of normal mice. After treatment with nanoparticles, the activities of GSH-Px and GST and other parameters related to the oxidative stress were downregulated and tended closely to the normal levels. Pulmonary histopathological results also showed that two different types of water-soluble fullerenes can prevent lungs from inflammatory lesion and tumor invasion. These findings indicate two different types of water-soluble fullerenes materials can downregulate the oxidative stress status by scavenging excessive free radicals and inhibiting the lipid peroxidation in tumor-bearing mice, which can partly explain their protective roles on the pulmonary oxidative-damage induced by the tumor metastasis to lung tissues.
Journal of Nanoscience and Nanotechnology 12/2010; 10(12):8632-7. · 1.56 Impact Factor
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Yang Liu, Yuxi Gao,
Lili Zhang,
Tiancheng Wang,
Jiangxue Wang,
Fang Jiao,
Wei Li,
Ying Liu,
Yufeng Li,
Bai Li,
Zhifang Chai,
Gang Wu,
Chunying Chen
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ABSTRACT: The purpose of this study is to evaluate the overall toxicity of nasal instilled nanoscale copper particles (23.5 nm) in mice. Pathological examination, target organs identification, and blood biochemical assay of experimental mice were carried out in comparison with micro-sized copper particles (17 microm). However, only in the high-dose group of copper nanoparticles (40 mg/kg body weight instilled for three times in one week), the body weight of mice were retarded and significant pathological changes were observed. There were hydropic degeneration around the central vein and the spotty necrosis of hepatocytes in the liver and swelling in the renal glomerulus, while, severe lesion associated with the decreased number of olfactory cells and the dilapidated laminated structure were also observed in the olfactory bulb. The serum biochemical assay also indicated the sign of renal and hepatic lesion. However, there were no obvious pathological and physiological damages in the mice after instilling different-sized copper nanoparticles with low dose of 1 mg/kg body weight. The retention and distribution of copper in various tissues show that the liver, kidneys and olfactory bulb are the main accumulated tissues for copper particles, which were determined by high sensitive element-specific technique of ICP-MS. The copper contents of the liver, kidneys and the olfactory bulb increase significantly at the group of 40 mg/kg compared to the control group, which is in agreement with the histological changes. Therefore, the data indicate that nasal inhaled copper particles at very high dosage can translocate to other organs and tissues and further induce certain lesions. The present results are helpful to get better understanding of the risk assessment and evaluation for copper nanoparticles.
Journal of Nanoscience and Nanotechnology 11/2009; 9(11):6335-43. · 1.56 Impact Factor
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ABSTRACT: The excellent optical characteristics of quantum dots make them applied widely in the field of live sciences. Meanwhile, the toxicity of quantum dots have attracted a lot of scientific research staff's attention all around the world. In this paper, the fundamental properties of quantum dots, the progress in quantum dots characteristics, structure, and toxicity were introduced, mainly focusing on the research in cytotoxicity of quantum dots and their influencing factors in recent years.
Wei sheng yan jiu = Journal of hygiene research 12/2008; 37(6):760-3.
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Jiangxue Wang,
Chunying Chen,
Ying Liu,
Fang Jiao,
Wei Li,
Fang Lao,
Yufeng Li,
Bai Li,
Cuicui Ge,
Guoqiang Zhou, Yuxi Gao,
Yuliang Zhao,
Zhifang Chai
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ABSTRACT: Nanoscale titanium dioxide (TiO(2)) is massively produced and widely used in living environment, which hence make the potential risk to human health. Central nervous system (CNS) is the potential susceptible target of inhaled nanoparticles, but the studies on this aspect are limited so far. We report the accumulation and toxicity results in vivo of two crystalline phases of TiO(2) nanoparticles (80nm, rutile and 155nm, anatase; purity >99%). The female mice were intranasally instilled with 500microg of TiO(2) nanoparticles suspension every other day for 30 days. Synchrotron radiation X-ray fluorescence analysis (SRXRF) and inductively coupled plasma mass spectrometry (ICP-MS) were used to determine the contents of titanium in murine brain. Then, the pathological examination of brain tissue, oxidative stress-mediated responses, and levels of neurochemicals in the brain of exposed mice were also analyzed. The obvious morphological changes of hippocampal neurons and increased GFAP-positive astrocytes in the CA4 region were observed, which were in good agreements with higher Ti contents in the hippocampus region. Oxidative stress occurred obviously in whole brain of exposed mice such as lipid peroxidation, protein oxidation and increased activities of catalase, as well as the excessive release of glutamic acid and nitric oxide. These findings indicate anatase TiO(2) nanoparticles exhibited higher concern on some tested biological effects. To summarize, results provided the preliminary evidence that nasal instilled TiO(2) nanoparticles could be translocated into the central nervous system and cause potential lesion of brain, and the hippocampus would be the main target within brain.
Toxicology Letters 10/2008; 183(1-3):72-80. · 3.23 Impact Factor
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ABSTRACT: Hair is a well-established and widely used matrix for measuring mercury exposure of an individual. Although a variety of washing procedures to remove external mercury contamination have been proposed, no standardized procedures are available yet. In this study, different washing reagents like l-cysteine (Cys), 2-mercaptoethanol (ME), and disodium diaminoethanetetra acetate (EDTA) were used to find out if it is possible to remove mercury contamination from human scalp hair spiked with HgCl2 solutions at different concentrations. It was found that the external mercury contamination could not be fully washed off even using reagents with high affinity to mercury like l-cysteine and ME. However, for the well-pulverized CRM hair samples some of the endogenous mercury was washed off. It suggests that hair is not a suitable biomarker for evaluation of total mercury exposure especially in people like mercury miners or gold miners/burners associated with serious external Hg exposure. However, hair still can be used as an indicator for methyl mercury exposure because, generally, there is almost no exogenous contamination of methyl mercury in hair.
Environmental Research 06/2008; 107(1):39-44. · 3.40 Impact Factor
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Wei Li,
Chunying Chen,
Chang Ye,
Taotao Wei,
Yuliang Zhao,
Fang Lao,
Zhen Chen,
Huan Meng, Yuxi Gao,
Hui Yuan,
Genmei Xing,
Feng Zhao,
Zhifang Chai,
Xujia Zhang,
Fuyu Yang,
Dong Han,
Xianhua Tang,
Yingge Zhang
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ABSTRACT: Manufactured fullerene nanoparticles easily enter into cells and hence have been rapidly developed for biomedical uses. However, it is generally unknown which route the nanoparticles undergo when crossing cell membranes and where they localize to the intracellular compartments. Herein we have used both microscopic imaging and biological techniques to explore the processes of [C(60)(C(COOH)(2))(2)](n) nanoparticles across cellular membranes and their intracellular translocation in 3T3 L1 and RH-35 living cells. The fullerene nanoparticles are quickly internalized by the cells and then routed to the cytoplasm with punctate localization. Upon entering the cell, they are synchronized to lysosome-like vesicles. The [C(60)(C(COOH)(2))(2)](n) nanoparticles entering cells are mainly via endocytosis with time-, temperature- and energy-dependent manners. The cellular uptake of [C(60)(C(COOH)(2))(2)](n) nanoparticles was found to be clathrin-mediated but not caveolae-mediated endocytosis. The endocytosis mechanism and the subcellular target location provide key information for the better understanding and predicting of the biomedical function of fullerene nanoparticles inside cells.
Nanotechnology 04/2008; 19(14):145102. · 3.98 Impact Factor
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Yu-Feng Li,
Chunying Chen,
Bai Li,
Wei Li,
Liya Qu,
Zeqin Dong,
Masaharu Nomura, Yuxi Gao,
Jinxuan Zhao,
Wei Hu,
Yuliang Zhao,
Zhifang Chai
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ABSTRACT: Human hair and blood samples from persons living in the town of Wanshan, a mercury mine area in Guizhou Province of China, were collected and the quantitative speciation and structural information of Hg and S in hair samples and of Hg in erythrocyte and serum samples were studied using X-ray absorption spectroscopy. Least-squares fitting of the X-ray absorption near-edge spectra found that inorganic mercury is the major mercury species in hair samples (91.74%), while inorganic and methyl mercury are both about 50% of total mercury in RBC and serum samples, which is in agreement with the data obtained by acidic extraction, fractionation of Hg(2+) and CH(3)Hg(+) and quantification by ICP-MS. Curve-fitting analysis revealed that the Hg-S bond length and coordination number in hair were 0.248+/-0.002 nm and 3.10, respectively, while the S-Hg bond length and coordination number in hair were 0.236+/-0.002 nm and 4.05. The Hg-S bond length and coordination number in RBC were 0.251+/-0.003 nm and 4.09, respectively, while they were 0.228+/-0.002 nm and 4.08 in serum, respectively. The techniques for speciation, structural and binding information described in this study will find the potential application in similar studies of other elements.
Journal of Inorganic Biochemistry 04/2008; 102(3):500-6. · 3.35 Impact Factor
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ABSTRACT: The aim of this study was to investigate the relationship between metalloproteins distributions and cancer development in human liver tissues.
Proteins in the cytosol and microsome of tumor and surrounding nontumor tissues from five individuals with HCC were separated with isoelectric focusing. Zinc, iron, copper, and manganese contents in protein bands were measured with synchrotron radiation X-ray fluorescence.
In the cytosol, the metal contents in protein bands from tumor tissues were generally less than those from corresponding nontumor tissues, especially in the Fe-containing bands with isoelectric points of 6.5 and 8.0, and Cu, Zn-containing band of 5.5. However, reversed metal contents in Fe, Cu-containing band of 4.0 and Zn-containing bands of 3.9 and 4.3 were observed. In microsomes, the metal contents of protein bands were generally similar between tumor and nontumor tissues, but the Fe content in tumor tissues was 2.5-fold lower in the band of 5.9, the Cu and Zn contents were 2 and 3.5-fold higher in the band of 9.3, respectively, compared to that of nontumor tissues.
Metal distributions among the detected metal-containing bands are distinguishable between tumor and nontumor tissues. The difference of the distribution may be involved in the carcinogenesis of the liver tissues.
Hepato-gastroenterology 01/2008; 54(80):2291-6. · 0.66 Impact Factor
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ABSTRACT: Mercury (Hg)-, selenium (Se)-, and arsenic (As)- containing proteins in liver tissues of bighead carp and grass carp sampled from a mercury-polluted area of Wanshan, Guizhou Province, China, were separated by thin-layer isoelectric focusing. The relative content of Hg, Se, and As in protein bands was measured with synchrotron radiation x-ray fluorescence. The results indicated that there were at least 3 Hg-containing bands with pI 3.7, 4.8, and 6.2 in liver of bighead carp and 1 Hg-containing band with pI 6.2 in grass carp. Se and As were found in the Hg-containing bands 3.7 in bighead carp and 6.2 in grass carp. The bands may be corresponding to the antagonistic effect of Se against the toxicity of Hg and As. In addition, Hg and As often coexist in the same band, suggesting that the two elements may be involved in the same metabolic processes.
Journal of Toxicology and Environmental Health Part A 01/2008; 71(18):1266-9. · 1.83 Impact Factor
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ABSTRACT: The present study was carried out to establish a method for simultaneous speciation analysis of selenium and mercury. Batch-wise elution using two different mobile phases that are suitable for selenium and mercury speciation leads to successful determination of both selenium and mercury standards in 30 minutes with good efficiency and resolution. The detection limits are in the range of 0.05–0.3 mg L À1 for selenium species, except TMSe, which has a poorer detection limit (1.48 mg L À1), and 2.5 mg L À1 for inorganic mercury (Hg 2+) and 2.0 mg L À1 for organic mercury (CH 3 Hg +). The method was applied to analysis of urine samples from people who were long-term mercury exposed and supplemented with selenium-enriched yeast for 90 days. Selenocystine (SeCys) was found to be a major selenium form, while inorganic mercury is the major mercury form. The recoveries of spiked species were between 93 and 117% in all cases. The increased mercury concentrations in urine after 90-day selenium supplementation suggest that selenium is beneficial to the excretion of mercury from urine. The proposed technique may help to increase our understanding of the in vivo interaction between selenium and mercury in human body.
04/2007;
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Jiangxue Wang,
Guoqiang Zhou,
Chunying Chen,
Hongwei Yu,
Tiancheng Wang,
Yongmei Ma,
Guang Jia, Yuxi Gao,
Bai Li,
Jin Sun,
Yufeng Li,
Fang Jiao,
Yuliang Zhao,
Zhifang Chai
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ABSTRACT: In order to evaluate the toxicity of TiO(2) particles, the acute toxicity of nano-sized TiO(2) particles (25 and 80nm) on adult mice was investigated compared with fine TiO(2) particles (155nm). Due to the low toxicity, a fixed large dose of 5g/kg body weight of TiO(2) suspensions was administrated by a single oral gavage according to the OECD procedure. In 2 weeks, TiO(2) particles showed no obvious acute toxicity. However, the female mice showed high coefficients of liver in the nano-sized (25 and 80nm) groups. The changes of serum biochemical parameters (ALT/AST, LDH) and pathology (hydropic degeneration around the central vein and the spotty necrosis of hepatocytes) of liver indicated that the hepatic injury was induced after exposure to mass different-sized TiO(2) particles. In addition, the nephrotoxicity like increased BUN level and pathology change of kidneys was also observed in the experimental groups. The significant change of serum LDH and alpha-HBDH in 25 and 80nm groups showed the myocardial damage compared with the control group. However, there are no abnormal pathology changes in the heart, lung, testicle (ovary), and spleen tissues. Biodistribution experiment showed that TiO(2) mainly retained in the liver, spleen, kidneys, and lung tissues, which indicated that TiO(2) particles could be transported to other tissues and organs after uptake by gastrointestinal tract.
Toxicology Letters 02/2007; 168(2):176-85. · 3.23 Impact Factor
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Yu-Feng Li,
Chunying Chen,
Bai Li, Qing Wang, Jiangxue Wang, Yuxi Gao, Yuliang Zhao, Zhifang Chai
Journal of Analytical Atomic Spectrometry - J ANAL ATOM SPECTROM. 01/2007; 22(8).
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Jiangxue Wang,
Chunying Chen,
Bai Li,
Hongwei Yu,
Yuliang Zhao,
Jin Sun,
Yufeng Li,
Gengmei Xing,
Hui Yuan,
Jun Tang,
Zhen Chen,
Huan Meng, Yuxi Gao,
Chang Ye,
Zhifang Chai,
Chuanfeng Zhu,
Baocheng Ma,
Xiaohong Fang,
Lijun Wan
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ABSTRACT: Oxidative stress is considered to be one of the important mechanisms involved in carcinogenesis. In our previous study, gadolinium endohedral metallofullerenol ([Gd@C82(OH)22]n nanoparticles) have shown high inhibitory activity on hepatoma cell (H22) growth in mice. To explore the antioxidative functions of nanoparticles, we investigated the biodistribution of [Gd@C82(OH)22]n nanoparticles, the changes of blood coagulation profiles, the metabolism of reactive oxygen species (ROS) in the tumor-bearing mice as well as the possible relationships between nanoparticles treatment and ROS production in this paper. The activities of hepatic superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione S-transferase (GST) and catalase (CAT) as well as the levels of reduced glutathione (GSH), protein-bound thiols and malondialdehyde (MDA) were compared between the tumor-bearing mice and normal mice. Transplanted tumors were grown in mice by subcutaneous injection of murine hepatoma cells in the mice. The comparison of the above parameters between nanoparticles and cyclophosphamide (CTX) therapy were also investigated. [Gd@C82(OH)22]n administration can efficiently restore the damaged liver and kidney of the tumor-bearing mice. All the activities of enzymes and other parameters related to oxidative stress were reduced after [Gd@C82(OH)22]n treatment and tended closely to the normal levels. The results suggest that [Gd@C82(OH)22]n nanoparticle treatment could regulate ROS production in vivo.
Biochemical Pharmacology 04/2006; 71(6):872-81. · 4.70 Impact Factor
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ABSTRACT: OBJECTIVE The antioxidative system in human hepatocellular carcinoma was investigated.
METHODS The activities of cytosolic catalase (CAT), superoxide dismutase, glutathione peroxidase (GSH-Px), glutathione S-tranferase
and levels of reduced glutathione, total protein thiols and malondialdehyde were assayed in 10 cases of hepatocellular carcinoma
and adjacent normal liver.
RESULTS Hepatoma tissues showed higher activities of CAT, GSH-Px and lower content of total antioxidative capacity compared to adjacent
normal liver tissue (P<0.05).
CONCLUSION These findings suggest that the antioxidative defense — related enzymes and antioxidants are largely regulated in hepatoma
cells. However, the mechanism which is not clear requires further investigation.
Chinese Journal of Clinical Oncology 01/2006; 3(1):11-14.
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Chinese Journal of Analytical Chemistry - CHINESE J ANAL CHEM. 01/2006; 34(4):443-446.
