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《African Journal of Aquatic Science》2013,38(1):197-201
In late August 1998, a mechanical malfunction at the Nylstroom Sewage Treatment Works resulted in a massive quantity of untreated sewage flowing into the Klein Nyl River. Simultaneously, 5km upstream, a poly-aromatic hydrocarbon poison was simultaneously leaked into the same river from a 25 litre canister. These spills threatened the Nylsvley Nature Reserve, a newly acclaimed RAMSAR site, situated about 20km downstream of Nylstroom. The Limnological team of the Department of Zoology, University of the North, was asked to assist with the assessment of the effect of these spills, which resulted in a massive fish kill. A monitoring program was implemented in early September 1998 to assess the effect of these spills on the water quality of the receiving water body. The implications of the altered water quality on the aquatic biota are discussed. 相似文献
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Koichi Inoue Deborah Branigan Zhi-Gang Xiong 《The Journal of biological chemistry》2010,285(10):7430-7439
Transient receptor potential melastatin 7 (TRPM7) channels are novel Ca2+-permeable non-selective cation channels ubiquitously expressed. Activation of TRPM7 channels has been shown to be involved in cellular Mg2+ homeostasis, diseases caused by abnormal magnesium absorption, and in Ca2+-mediated neuronal injury under ischemic conditions. Here we show strong evidence suggesting that TRPM7 channels also play an important role in cellular Zn2+ homeostasis and in Zn2+-mediated neuronal injury. Using a combination of fluorescent Zn2+ imaging, small interfering RNA, pharmacological analysis, and cell injury assays, we show that activation of TRPM7 channels augmented Zn2+-induced injury of cultured mouse cortical neurons. The Zn2+-mediated neurotoxicity was inhibited by nonspecific TRPM7 blockers Gd3+ or 2-aminoethoxydiphenyl borate, and by knockdown of TRPM7 channels with small interfering RNA. In addition, Zn2+-mediated neuronal injury under oxygen-glucose deprivation conditions was also diminished by silencing TRPM7. Furthermore, we show that overexpression of TRPM7 channels in HEK293 cells increased intracellular Zn2+ accumulation and Zn2+-induced cell injury, while silencing TRPM7 by small interfering RNA attenuated the Zn2+-mediated cell toxicity. Thus, TRPM7 channels may represent a novel target for neurological disorders where Zn2+ toxicity plays an important role. 相似文献
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TMCd1 is a cadmium inducible metallothionein (MT) gene. In the present study the TMCd1 gene of a ciliate protozoan has been expressed in E. coli and the function of the expressed TMCd1 protein as a metal-binding protein has been evaluated. The growth of E. coli cells expressing the GST fused TMCd1 proteins in the presence of cadmium metal clearly demonstrated the role of TMCd1 as a metal-binding protein. The metal accumulation experiments showed that the bacterial cells expressing the functional TMCd1 protein accumulated 19-fold more cadmium in contrast to control cells that lacked the TMCd1 protein expression. The results clearly demonstrate a physiological role of full length TMCd1 protein of a ciliate, expressed in E. coli, in cadmium metal sequestration and detoxification. 相似文献
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W. Malorni R. Rivabene M. T. Santini G. Rainaldi G. Donelli 《Redox report : communications in free radical research》2013,18(1):57-64
It has been hypothesized that reactive oxygen intermediates (ROI) can activate human immunodeficiency virus (HIV) replication and that HIV can trigger programmed cell death (PCD). In this work, we studied PCD in U937 cultured cells chronically infected with HIV and exposed to tumor necrosis factor alpha (TNFα). This cytokine has been shown to induce apoptosis in some cell types and to produce intracellular free radical species including ROI. In addition, it was also demonstrated that HIV-induced PCD observable in U937 infected cells can be favored by TNF exposure. In one of our recent works, evidence was presented that the thiol supplier N-acetylcysteine (NAC) can ‘protect’, at least partially, HIV-infected cells from PCD and determine a significant decrease in viral progeny. In the present work, we demonstrate (a) that apoptosis can be easily induced by TNF only in infected U937 cells and not in control wild-type cells, (b) that daily treatment of TNF-exposed cells with low concentrations of NAC is able to impair viral progeny formation as early as 24 h, (c) that the mitochondrial damage induced by TNF is counteracted by preexposure to NAC, and (d) that NAC alone exerts changes in mitochondria which may be responsible for the protective effects exerted by this compound. Because of the radical producing capacity of TNF, these results seem to indicate that the protective effects of NAC may be due to the specific antioxidant nature of this substance which appears to be capable of impairing both the apoptotic machinery and viral replication by an intracellular mechanism involving mitochondrial integrity and function. 相似文献
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Nasser Hashemi Goradel Hamed Mirzaei Amirhossein Sahebkar Mohsen Poursadeghiyan Aria Masoudifar Ziba Veisi Malekshahi Babak Negahdari 《Journal of cellular biochemistry》2018,119(1):207-212
Release of harmful pollutants such as heavy metals, pesticides, and pharmaceuticals to the environment is a global concern. Rapid and reproducible detection of these pollutants is thus necessary. Biosensors are the sensitive and high specific tools for detection of environmental pollutants. Broad range various types of biosensors have been fabricated for this purpose. This review focuses on the feature and application of biosensors developed for environmental and urban pollutants detection. J. Cell. Biochem. 119: 207–212, 2018. © 2017 Wiley Periodicals, Inc. 相似文献
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《African Journal of Aquatic Science》2013,38(2):213-220
Nakivubo wetland, which has performed tertiary water treatment for Kampala city for the past 40 years, is ecologically stressed by agricultural and infrastructural developments. Field studies were carried out to assess the hydraulic loading, pollution profile, stability and water quality of this wetland. The upper and lower Nakivubo wetland receive 4.13?7.66 × 104 and 3.50?10.32 × 104m3/day of water respectively, of which 48.3–57.9% of total hydraulic loading to the upper wetland was carried by sampling station S1. The influent water to the upper wetland had a total BOD5 and NH4-N loading ranging from 2.6?4.4 × 103kg BOD/day and 0.79?1.68 × 103kg NH4-N/day respectively. The National Water and Sewerage Corporation's effluent constituted a large proportion of BOD and NH4-N loading into Nakivubo wetland. Zinc, copper and chromium were detected in trace amounts at most sampling stations. However, lead was occasionally detected at Kibira channel (station S5) at a concentration of 0.4mg/l, which is higher than the permitted Ugandan discharge limit of 0.1mg/l (NEMA 1999). The wetland showed a very high removal efficiency for BOD, ranging from 77.4%–86.3%, compared to ammonium-N which ranged from ?66.1% to 33.1% indicating limitations with the nitrification process. A low self-purification for zinc, copper and chromium was also observed in the upper Nakivubo wetland, possibly due to poor plant-wastewater interaction resulting from wetland drainage. In the lower Nakivubo wetland conductivity and dissolved oxygen were generally higher in papyrus- than in Miscanthidium-vegetated zones. However, the BOD and ammonium-N loadings did not vary significantly (P = 0.217 and P = 0.359 respectively) between the two vegetated zones. 相似文献
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《African Journal of Aquatic Science》2013,38(3):245-249
The Sidi Kamber Mine, abandoned since 1976, is still a source of acidic drainage entering the Oued Es-Souk River. An investigation of the rate of pollution of the Oued Es-Souk and the variation of its water quality showed that the mining waters are very acidic, with high concentrations of sulphate ions and dissolved heavy metals. Only lead reaches a significant level in the suspended matter. During mixing of the acid stream waters with uncontaminated river water, an amorphous orange precipitate forms and contributes to the removal of sulphate and certain heavy metals by adsorption and co-precipitation. Downstream, zinc and lead are concentrated in the sediments, while cadmium is mainly transported in the dissolved phase. 相似文献
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