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Zhan Q.,Key Laboratory of Environmental Medicine and Engineering | Tang M.,Key Laboratory of Environmental Medicine and Engineering
Biological Trace Element Research

Recently, quantum dots (QDs) have been widely applied in biological and biomedical fields such as cell labeling, living tissue imaging, and photodynamic therapy because of their superior optical properties. Meanwhile, the potential biological negative effects and/or toxic effects of QDs have become increasingly important, especially the cytotoxicity caused by QDs. One of the common cytotoxicity when living organisms are treated with QD is apoptosis, where many attempts have been made to explain the mechanisms of apoptosis caused by QDs’ use. One of the mechanisms is the production of cadmium ion (Cd2+) and reactive oxygen species (ROS). Excess generation of ROS will result in oxidative stress that would mediate apoptosis. Furthermore, the activation of cell death receptors and mitochondria-dependent such as B cell lymphoma 2 (Bcl-2) family and the caspase family could onset apoptosis. Signal transduction such as some classical signal pathways of PI3K-AKT, NF-E2-related factor 2 (Nrf2)-antioxidant response element (ARE), mitogen-activated protein kinases (MAPKs), and nuclear factor kappa B (NF-κB) also plays an important role in the regulation of apoptosis. Several ways to reduce the apoptotic rate have been introduced, such as surface modification, controlling, the dose, size, and exposure time of QDs as well as using antioxidants or inhibitors. In this review, we attempted to review the most recent findings associated with apoptosis caused by QDs so as to provide some guidelines for a safer QD application in the future. © 2014, Springer Science+Business Media New York. Source

Gui S.,Soochow University of China | Zhang Z.,Soochow University of China | Zheng L.,Soochow University of China | Cui Y.,Soochow University of China | And 11 more authors.
Journal of Hazardous Materials

Numerous studies have demonstrated that damage of kidney of mice can be caused by exposure to titanium dioxide nanoparticles (TiO 2 NPs). However, the molecular mechanism of TiO 2 NPs-induced nephric injury remains unclear. In this study, the mechanism of nephric injury in mice induced by an intragastric administration of TiO 2 NPs was investigated. The results showed that TiO 2 NPs were accumulated in the kidney, resulting in nephric inflammation, cell necrosis and dysfunction. Nucleic factor-κB was activated by TiO 2 NPs exposure, promoting the expression levels of tumor necrosis factor-α, macrophage migration inhibitory factor, interleukin-2, interleukin-4, interleukin-6, interleukin-8, interleukin-10, interleukin-18, interleukin-1β, cross-reaction protein, transforming growth factor-β, interferon-γ and CYP1A1, while heat shock protein 70 expression was inhibited. These findings implied that TiO 2 NPs-induced nephric injury of mice might be associated with alteration of inflammatory cytokine expression and reduction of detoxification of TiO 2 NPs. © 2011 Elsevier B.V. Source

Liang G.,Key Laboratory of Environmental Medicine and Engineering | Liang G.,Nanjing Southeast University | Zhang T.,Nanjing University | Liu R.,Key Laboratory of Environmental Medicine and Engineering | And 7 more authors.
Journal of Nanoscience and Nanotechnology

The functional modification of the outer surface of carbon nanotubes (CNTs) is likely to improve their biocompatibility. Therefore, CNTs have attracted great attention not only in electrical, optical and mechanical applications but also in biological and pharmaceutical applications. Thus, it is important to examine the biodistribution and kinetics of the carbon-based nanotubes when they are introduced into living systems. Here, we synthesized and characterized tyrosine-functionalized carbon nanotubes (CNTs-Tyr), and assessed the biodistribution profile of CNTs-Tyr in mice, following three different administrations by the 125l radioisotope tracer method. CNTs-Tyr was delivered quickly around the entire body, and different absorbtion and biodistribution profiles of CNTs-Tyr were observed with different routes of administration. Following intravenous injection, CNTs-Tyr accumulated within 24 h mainly in the lungs and slightly in the spleen and liver, and may be eliminated primarily through the kidneys. After administration via gavage, most of the CNTs-Tyr were eliminated through the intestine, and rarely delivered into the organs. After intraperitoneal injection, CNTs-Tyr accumulated in the spleen and were rapidly eliminated from the other organs within 24 h. The blood circulation half-life of CNTs-Tyr was about 4.4 h. The behavior of CNTs-Tyr in mice is somewhat different from the results reported previously. This suggests that the functionalized group may affect the affinity of carbon nanotubes for particular organs. The results provide basic biological information for the biomedical application and risk assessment of CNTs. Copyright © 2010 American Scientific Publishers. Source

Jian-Ru W.,Key Laboratory of Environmental Medicine and Engineering | Jian-Ru W.,Nanjing Southeast University | Bei W.,Key Laboratory of Environmental Medicine and Engineering | Bei W.,Nanjing Southeast University | And 4 more authors.
Epidemiology and Infection

The aim of this study was determine the prevalence of Mycoplasma hominis, M. genitalium, M. fermentans, M. pirum, M. penetrans and Ureaplasma urealyticum in HIV-infected patients. Culture and PCR were used to detect six species of Mycoplasma in first-void urine of HIV-1 infected men. A total of 497 HIV/AIDS patients (age range 5-75 years, mean 37 years) were screened in the study. All presented positive for at least one kind of mycoplasma, especially U. urealyticum and M. hominis. Six mycoplasmas were significant in the homosexual contact and heterosexual contact groups. The distribution of M. hominis, M. penetrans, and M. pirum were significantly different in this four-transmission category. CD4 + cell count levels were lower in the AIDS-associated Mycoplasma-positive group than in the Mycoplasma-negative group (P<0·01). This study indicates that U. urealyticum, M. hominis and M. fermentans are prevalent in HIV-1-infected male patients. This may be an indication of whether mycoplasmas are co-factors in the progression of HIV disease. © 2011 Cambridge University Press. Source

Li J.,Key Laboratory of Environmental Medicine and Engineering | Li J.,Nanjing Southeast University | Qiu Y.,Key Laboratory of Environmental Medicine and Engineering | Long H.,Key Laboratory of Environmental Medicine and Engineering | And 3 more authors.
2011 International Conference on Remote Sensing, Environment and Transportation Engineering, RSETE 2011 - Proceedings

This paper reports before and after the low frequency low power ultrasound were treated with different concentrations of algae in Taihu Lake sample water quality changes, and we have found that low frequency and low power ultrasonic can not only safe and efficient removal of algae in Taihu Lake, and the treated water quality improved significantly. After two times of ultrasonic treatment and for 24 hours, high, medium and low concentrations of algae in water samples by nitrogen (TN) dropped 75.8%, 73.2%, 72.9%, total phosphorus (TP) declined 62.2%, 63.5%, 72.9% Chemical oxygen demand (COD) decreased significantly, TP/TN values increased from 0.3-0.36 to 0.6-0.89, the physical and chemical properties of sample water is almost not affected. © 2011 IEEE. Source

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