Enhancement on selenium volatilization for phytoremediation: role of plant and soil microbe interaction.

This study aimed at quantifying the potential effects of plant and soil microbial interaction on selenium (Se) volatilization, with the specific objectives of identifying soil bacteria associated with rabbitfoot grass () and demonstrating the enhancement of Se volatilization in the soil-Indian mustard () system through inoculation of the soil with the identified best Se-volatilizing bacterial strain. Soil bacteria were isolated from topsoil and rhizosphere soils of rabbitfoot grass, and the bacterial colonies were characterized via PCR-DGGE and DGGE band analysis prior to their identification using 16S rDNA sequencing technique. produced over 500-fold more volatile Se in a culture medium treated with 15 µg Se/mL (equal mixture of SeO , SeO and selenomethionine) than any of the other eight identified bacterial strains.

Selenium Removal from Wastewater by Microbial Transformation and Volatilization.

Selenium (Se) is a naturally occurring trace element that is nutritionally essential for humans and animals, but becomes toxic at high concentrations. This laboratory study explored the role of microbes in Se removal from contaminated wastewater via biological transformation and volatilization processes. Microbes could immobilize water-soluble selenate (SeO) and selenite (SeO) to water-insoluble elemental Se (Se) and transform Se into volatile Se compounds found in the atmosphere.

Topographic constraints on the distribution of selenium in the supergene environment: A case study at Yutangba, China.

The local topography and leaching conditions significantly affect the spatial distribution of selenium (Se) in the local environment. However, the driving factors controlling Se distribution have not been well addressed. In this paper, taking Yutangba, a village known for human selenosis in China, as an example, we demonstrate how topographic factors influence the spatial distribution of Se in soils and plants.

Synergistic Effect of Melatonin and Selenium Improves Resistance to Postharvest Gray Mold Disease of Tomato Fruit.

Melatonin (MT) is a ubiquitous hormone molecule that is commonly distributed in nature. MT not only plays an important role in animals and humans but also has extensive functions in plants. Selenium (Se) is an essential micronutrient for animals and humans, and is a beneficial element in higher plants at low concentrations.

Selenium Effect Threshold for Soil Nematodes Under Rice Biofortification.

Crop biofortification with inorganic selenium (Se) fertilizer is a feasible strategy to improve the health of residents in Se-deficient areas. For eco-friendly crop Se biofortification, a comprehensive understanding of the effects of Se on crop and soil nematodes is vital. In this study, a rice pot experiment was carried out to test how selenite supply (untreated control (0), 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 100, or 200 mg Se kg) in soil affected rice growth, rice Se accumulation, and soil nematode abundance and composition.

Zero-Valent Iron Nanoparticles Remediate Nickel-Contaminated Aqueous Solutions and Biosolids-Amended Agricultural Soil.

Nickel (Ni) accumulation in wastewater treatment sludge poses a potential environmental risk with biosolids-land application. An incubation experiment was conducted to evaluate the effect of nanoparticles of zero-valent iron (nZVI) on Ni sorption in biosolids-treated agricultural soils. Two application rates of biosolids (0, 5%, /) and four treatment levels (0, 1, 5, and 10 g/kg) of nZVI were examined, either separately or interactively.

[Clinical features and treatment of macrolide-resistant Mycoplasma pneumoniae pneumonia in children].

Objective: To study the clinical features of macrolide-resistant Mycoplasma pneumoniae pneumonia and its treatment regimens in children.

Methods: The samples of throat swab or bronchoalveolar lavage fluid were collected from 136 children with Mycoplasma pneumoniae pneumonia. Quantitative real-time PCR was used to detect 2063/2064 A:G mutation in 23S rRNA, and according to such results, the children were divided into drug-resistance group with 81 children and sensitive group with 55 children.

Selenium speciation in seleniferous agricultural soils under different cropping systems using sequential extraction and X-ray absorption spectroscopy.

Selenium (Se) speciation in soil is critically important for understanding the solubility, mobility, bioavailability, and toxicity of Se in the environment. In this study, Se fractionation and chemical speciation in agricultural soils from seleniferous areas were investigated using the elaborate sequential extraction and X-ray absorption near-edge structure (XANES) spectroscopy. The speciation results quantified by XANES technique generally agreed with those obtained by sequential extraction, and the combination of both approaches can reliably characterize Se speciation in soils.

Indications of Selenium Protection against Cadmium and Lead Toxicity in Oilseed Rape ( L.).

The present study investigated the beneficial role of selenium (Se) in protecting oilseed rape ( L.) plants from cadmium (Cd) and lead (Pb) toxicity. Exogenous Se markedly reduced Cd and Pb concentration in both roots and shoots.

Effect of Selenium on Control of Postharvest Gray Mold of Tomato Fruit and the Possible Mechanisms Involved.

Selenium (Se) has important benefits for crop growth and stress tolerance at low concentrations. However, there is very little information on antimicrobial effect of Se against the economically important fungus Botrytis cinerea. In the present study, using sodium selenite as Se source, we investigated the effect of Se salts on spore germination and mycelial growth of the fungal pathogen in vitro and gray mold control in harvested tomato fruit.

Biofortification and phytoremediation of selenium in China.

Selenium (Se) is an essential trace element for humans and animals but at high concentrations, Se becomes toxic to organisms due to Se replacing sulfur in proteins. Selenium biofortification is an agricultural process that increases the accumulation of Se in crops, through plant breeding, genetic engineering, or use of Se fertilizers. Selenium phytoremediation is a green biotechnology to clean up Se-contaminated environments, primarily through phytoextraction and phytovolatilization.

Inhibitory effect of selenium against Penicillium expansum and its possible mechanisms of action.

Some organic and inorganic salts could inhibit the growth of many pathogens. Selenium (Se), as an essential micronutrient, was effective in improving the plant resistance and antioxidant capacity at a low concentration. Penicillium expansum is one of the most important postharvest fungal pathogens, which can cause blue mold rot in various fruits and vegetables.

Development of a constructed wetland water treatment system for selenium removal: incorporation of an algal treatment component.

On the basis of the fact that algae have the ability to volatilize substantial quantities of selenium (Se), we investigated the concept of including an algal pretreatment unit into a constructed wetland system for the removal of Se from river water entering the Salton Sea. Of six different algal strains tested, the most effective in terms of Se volatilization and Se removal from the water column was a Chlorella vulgaris strain (designated Cv). Cv removed 96% of Se (supplied as selenate) from the microcosm water column within 72 h, with up to 61% being removed by volatilization to the atmosphere.

A novel selenocystine-accumulating plant in selenium-mine drainage area in Enshi, China.

Plant samples of Cardamine hupingshanesis (Brassicaceae), Ligulariafischeri (Ledeb.) turcz (Steraceae) and their underlying top sediments were collected from selenium (Se) mine drainage areas in Enshi, China. Concentrations of total Se were measured using Hydride Generation-Atomic Fluorescence Spectrometry (HG-AFS) and Se speciation were determined using liquid chromatography/UV irradiation-hydride generation-atomic fluorescence spectrometry (LC-UV-HG-AFS).

Single wall carbon nanotube induced inflammation in cruor-fibrinolysis system.

Objective: To study single wall carbon nanotubes (SWCNT) and its role in inducing inflammatory cytokines in the cruor-fibrinolysis system of rat.

Methods: Twenty one Wistar rats were divided into four groups: 1) control; 2) low-dose SWCNT (0.15 mg/kg BW); 3) medium-dose SWCNT (0.

Human Health Risk Assessment of 16 Priority Polycyclic Aromatic Hydrocarbons in Soils of Chattanooga, Tennessee, USA.

South Chattanooga has been home to foundries, coke furnaces, chemical, wood preserving, tanning and textile plants for over 100 years. Most of the industries were in place before any significant development of residential property in the area. During the 1950s and 1960s, however, the government purchased inexpensive property and constructed public housing projects in South Chattanooga.

Impact of traffic emissions on local air quality and the potential toxicity of traffic-related particulates in Beijing, China.

Objective: Air-borne particulates from different sources could have different physicochemical properties and inflammatory potentials. This study aims to characterize the chemical compositions and the toxicity of ambient particulate matter (PM) associated with traffic emissions.

Methods: The concentrations of trace elements, organic carbon (OC), elemental carbon (EC) and polycyclic aromatic hydrocarbons (PAHs) in PM2.

Single-wall carbon nanotubes induce oxidative stress in rat aortic endothelial cells.

Oxidative stress is a major factor contributing to endothelial cell damage. Single-wall carbon nanotubes (SWCNTs) have oxidative properties; however, the oxidative effects of SWCNTs on endothelial cells are not fully understood. In the present study, we investigated the effects of oxidative stress induced by SWCNTs on rat aortic endothelial cells (RAECs).

[Linezolid versus vancomycin in the treatment of pneumonia caused by Gram-positive cocci: meta-analysis of randomised controlled trials].

Objective: To study the randomised controlled trials on the efficacy and safety in patients with pneumonia caused by Gram-positive cocci treated with linezolid versus with vancomycin.

Methods: The data were collected from the MEDLINE database, EMBASE, OVID, the Cochrane library, and Chinese Biomedical Database, and the references of eligible studies were manually screened. Randomized controlled trials published in the English and Chinese literatures comparing linezolid with vancomycin in patients with pneumonia caused by Gram-positive cocci were eligible for inclusion.

Single-walled carbon nanotube induction of rat aortic endothelial cell apoptosis: Reactive oxygen species are involved in the mitochondrial pathway.

The use of nano-sized materials offers exciting new options in technical and medical applications. Single-walled carbon nanotubes are emerging as technologically important in different industries. However, adverse effects on cells have been reported and this may limit their use.

Oxidative damage to lung tissue and peripheral blood in endotracheal PM2.5-treated rats.

Objective: To investigate the oxidative damage to lung tissue and peripherial blood in PM2.5-treated rats.

Methods: PM2.

[Effect of interferon-alpha treatment in children with hepatitis B e antigen-positive chronic hepatitis B virus infection: a meta-analysis of follow-up for six months to two years].

Objective: To assess the efficacy and safety of interferon-alpha (IFN-alpha) in children with Hepatitis B e antigen-positive chronic hepatitis B virus infection.

Methods: PubMed and Chinese Biomedical Database were searched from the beginning of operation of the databases to April 2006, and the references of eligible studies were manually screened. Randomized controlled trials (RCTs) published in the English and Chinese literature comparing interferon-alpha with non-antiviral interventions (placebo or no treatment) in children with hepatitis B e antigen-positive chronic hepatitis B virus infection were eligible for inclusion.

Metal accumulation in eggs of the red-eared slider (Trachemys scripta elegans) in the Lower Illinois River.

The Illinois River is a highly utilized navigable waterway in the US Midwest, and has historically been contaminated with metal toxicants from various industrial and municipal pollution sources. Little information on metal contamination is available in the Lower Illinois River, and in particular, in the habitat of the red-eared slider (Trachemys scripta elegans) at the southern end of the river near Grafton, IL. This study was conducted to determine current levels of metal contamination in water, sediment, soil, and plants in the habitat, as well as to reveal temporal and spatial variations of metal accumulation in eggs of the red-eared slider.

Selenium removal by constructed wetlands: quantitative importance of biological volatilization in the treatment of selenium-laden agricultural drainage water.

Management of selenium (Se) -contaminated agricultural drainage water is one of the most important environmental issues in California. To evaluate the feasibility of utilizing constructed wetlands to remediate Se-laden drainage water and the role of biological volatilization in Se removal, 10 flow-through wetland cells were constructed in 1996 in Corcoran, California. The monthly monitoring study from May 1997 to December 1999 showed that the vegetated wetlands were capable of significantly reducing Se from the inflow drainage water; an average of 69.