Kocuria Flava Induced Growth and Chromium Accumulation in Cicer Arietinum L

In the present investigation a chromate tolerant rhizobacterium Kocuria flava was isolated and inoculated to the Cicer arietinum L to evaluate its effects on growth and chromium accumulation upon exposure of different concentration of chromium (1–10 μg ml^?1) as Cr (VI) for 24 d. K. flava inoculated plant of C. arietinum demonstrated luxuriant growth as compared to non inoculated plant at respective concentration of Cr (VI). K. flava found to ameliorate chromium induced phytotoxicity in terms of chlorophylls, carotenoid and protein contents and thus helps the plant in acquiring higher biomass with high chromium concentration. After 24 d, maximum concentration of chromium recorded in root of C. arietinum (4892.39 μg g^?1dw) inoculated with K. flava as compared to non inoculated plant (1762.22 μg g^?1dw) upon exposure of 5 μg ml^?1Cr (VI). Therefore, application of C. arietinum in association with K. flava could be more efficient in decontamination of chromium polluted site. Moreover, K. flava may be used as a bioresource for developing microbes assisted phytoremediation system due to its compatibility.     

What causes the vegetation types on Mount Bloomfield,a coastal tropical mountain of the western Philippines?

Mount Bloomfield has been shown to have several vegetation types, including medium stature forest on greywacke, small stature forest on serpentinized peridotite, and scrub and Gymnostoma woodland on dunite. The causes of the large physiognomic and floristic differences among these vegetation types have been investigated by soil chemical analyses, soil physical studies, and by a phytometer experiment involving the crop plant Zea mays. There was no relationship between maximum tree height and the soil chemical factors analysed (P, K, Ca, Mg, Ni) but there was a directly proportional relationship between maximum tree height and soil water retention. The phytometer experiment supported the idea that there is no acute soil toxicity in spite of the high soil Ni and Mg/Ca quotients recorded in this study. It is concluded that soil water retention, perhaps in combination with fire, is the major cause of stature differences among the vegetation types and together with soil chemistry is an important determinant of floristic composition.     

Cement-Organobentonite Admixtures for Stabilization/Solidification of PAH-Contaminated Soil: A Laboratory Study

The feasibility of using Portland cement and organobentonite to stabilize and solidify Polycyclic Aromatic Hydrocarbons (PAH) contaminated soil was examined. Naphthalene and phenanthrene in solid and dissolved phases were selected as PAHs compounds to represent organic contaminants in the soil. Different tests including Toxicity Characteristics Leaching Procedure (TCLP), Unconfined Compressive Strength (UCS), and permeability tests were conducted on the stabilization/solidification (S/S) contaminated soils. The leaching test results confirmed a significant reduction in the leaching of naphthalene and phenanthrene from the stabilized soil specimen by adding 2%, 5%, and 10% of organoclay during solidification/stabilization. Based on the results for the tested ranges of cement and organoclay for S/S contaminated soil, the optimum mix design includes 5% of cement and 2% of organoclay. The observation in this study confirmed that organoclay particles sorbed the organic contaminates and therefore naphthalene and phenanthrene leachate concentration will be reduced. Moreover, results show that increasing the curing time of S/S products reduces the naphthalene and phenanthrene leachate concentration.     

Environmental assessment of brownfield rehabilitation using two different life cycle inventory models

Goal, Scope and Background The primary goal of this paper is to present a LCI modelling approach that allows the inclusion of all three types of impacts. The approach is based on consequential LCA (CLCA) rather than more common attributional LCA (ALCA). In CLCA, system boundaries are expanded in order to include all significantly affected activities. In addition we show how changing from an attributional to a consequential approach alters how the impacts are evaluated, and discuss the applicability of these two distinct approaches to brownfield rehabilitation decision support. The paper is restricted to urban and contaminated brownfields that are the result of industrial use and whose rehabilitation is aimed at allowing residential redevelopment. Main Features The approach is based on an analogy between the open-loop recycling of material resources and brownfield rehabilitation. Brownfield rehabilitation is associated with two functions: (1) managing the legacy of past occupations on the site, analogous to a waste management function, and (2) providing redevelopable land, analogous to a commodity production function. The consequential system is expanded to cover the subsequent occupation life cycle of the brownfield and the effects on the occupation life cycles of other sites. The proposed model quantifies effects on sites competing to supply the same occupation function. Two approaches are proposed to determine the nature of the sites that are affected and to what extent they are affected: the first resembling a closed-loop approximation, and the second based on economic partial-equilibrium models. Results and Conclusions The scope of the CLCA is far more complex than that of the ALCA. It requires additional data that are associated with important sources of uncertainty. It does allow, however, for the inclusion of tertiary impacts, making it suitable for the evaluation of the often cited environmental benefits of reintegrating the site in the economy. In addition, the ALCA methodology seems to be inappropriate to compare brownfield management options that result in different subsequent uses of the site. Since the effects of this fate are included within the scope of CLCA, however, virtually any brownfield management option available to a decision-maker can aptly be compared. The evaluation of primary and secondary impacts also differs when the consequential approach is used rather than the attributional approach. It is impossible to anticipate the effects of these methodological differences on the results based on the qualitative discussion presented in this paper. Perspectives The complexity and uncertainty introduced by switching to a consequential approach is very high: it is therefore recommendable to evaluate the significance in the gain of environmental information in an actual case study to determine if system expansion is recommendable. Such a case study is presented in Part II to this paper. [39] Lesage P, Ekvall T, Deschênes L, Samson R (20006): Environmental Assessment of Brownfield Rehabilitation Using Two Different Life Cycle Inventory Models. Part 2: Case Study. Int J LCA, OnlineFirst (DOI: )     

Pharmacological intervention of biosynthesized Nigella sativa silver nanoparticles against hexavalent chromium induced toxicity in male albino mice

Hexavalent chromium, toxic heavy metal, among the top-rated environmental contaminants, is declared a potent endocrine disruptor in humans and animals. The present study was planned to find harmful effects on the reproductive system caused by Cr (VI) and the ameliorative effect of Nigella sativa and Nigella sativa-mediated AgNP on male mice (Mus musculus). In the present study, known infertility medicine, clomiphene citrate is also used as a positive control. The main objective of the present study was to assess the ameliorative potential of oral administration of a dose of 50 mg/kg BW clomiphene citrate (control), AgNP via chemical synthesis, Nigella sativa seed extract, and Nigella sativa-mediated AgNP against the Cr (VI) at the dose of 1.5 mg/kg BW from K₂Cr₂O₇ orally induced toxicity over eight weeks on the reproductive performance of male albino mice. Nigella sativa mediated AgNPs were characterized by UV, SEM, FTIR, and XRD. The histological analysis, smear study, antioxidant capacity test, and hormone analysis were conducted by blood samples of albino mice. Cr exposed groups showed a significant decrease in sperm head breadth (5.29 ± 0.54 µ) and length (19.54 ± 1.18 µ), middle piece length, tail length, LH (1.65 ± 0.15 ng/mL), testosterone (2.63 ± 0.29 ng/mL), SOD (61.40 ± 2.48 mmol/mL), CAT (87.40 ± 6.01 mmol/mL), GSH (1.54 ± 0.09 µmol/mL), and no of spermatogonia (1.22 ± 0.25), and spermatocytes (2.33 ± 0.943). However, FSH level (160.00 ± 4.98 ng/mL), seminiferous tubule CSA (1094.69 ± 49.76 mm²), size of spermatogonia (41.30 ± 1.24 µ), and spermatocytes (26.07 ± 1.34 µ) were significantly increased. Administration of Nigella sativa and Nigella sativa-mediated AgNPs reduced the toxicity.     

Ultra-thin strut cobalt chromium bare metal stent usage in a complex real-world setting. (SOLSTICE registry)

AimTo report clinical follow-up at 6 months after implantation of the ultra-thin strut cobalt chromium SolarFlex stent in a real-world setting.ConclusionsThe SOLSTICE registry showed that in a complex real-world setting the SolarFlex bare metal stent, with ultra-thin struts and customised scaffolding, provided low clinical MACE and TLR rates. These results provide support for the use of the latest generation bare metal stent in contemporary European practice.     

两株多环芳烃降解菌协同对菲-镉污染的去除特性北大核心

【目的】从污染土壤中分离筛选一株多环芳烃降解菌,并探究其与Pseudomonas aeruginosa B6-2构建的混菌体系对菲-镉复合污染的修复效能,以及微生物代谢特性对不同镉浓度赋存的响应特性,以期为复合污染的生物修复提供优良菌株资源及应用技术参考。【方法】采用富集驯化、筛选纯化方法得到一株多环芳烃降解菌,通过生理生化特征和16S rRNA基因序列分析进行鉴定。利用高效液相色谱法和电感耦合等离子体质谱法评估不同镉浓度赋存下各反应体系对菲和镉的去除效能;通过菌体细胞形态的扫描电镜观测及菌株代谢活性检测,探讨镉胁迫对菲生物降解过程的影响机制。【结果】筛选得到一株具有重金属耐受性和多环芳烃高效降解菌SZ-3,经鉴定为节杆菌属;降解菌协同体系(M)具有良好的菲降解效能和抗镉胁迫优势。镉胁迫浓度为0.5、10 mg/L时,M对菲和镉的去除率分别高于85%、80%;镉胁迫浓度为25、50 mg/L时,2种污染物的去除率均大于65%。扫描电镜分析表明,镉胁迫导致菌体表面粗糙且出现不同程度变形,菌体间黏附性和聚集性提高。反应周期内,邻苯二酚1,2-双加氧酶活性与电子传递体系活性随镉浓度增加而降低,两者变化与菲降解速率变化一致。【结论】Arthrobacter sp.SZ-3是一株PAHs高效降解菌,能与Pseudomonas aeruginosa B6-2协同高效修复菲-镉复合污染,随着初始镉胁迫浓度增加,混菌协同对目标污染物去除的优势显著。     

Role of direct reactivity with metals in chemoprotection by N-acetylcysteine against chromium(VI), cadmium(II), and cobalt(II)

The antioxidant N-acetylcysteine (NAC) is widely used for the assessment of the role of reactive oxygen species (ROS) in various biological processes and adverse drug reactions. NAC has been found to effectively inhibit the toxicity of carcinogenic metals, which was attributed to its potent ROS-suppressive properties. However, the absence of redox activity among some metals and findings from genetic models suggested a more diverse, smaller role of oxidative stress in metal toxicity. Here, we examined mechanisms of chemoprotection by NAC against Cd(II), Co(II), and Cr(VI) in human cells. We found that NAC displayed a broad-spectrum chemoprotective activity against all three metals, including suppression of cytotoxicity, apoptosis, p53 activation, and HSP72 and HIF-1α upregulation. Cytoprotection by NAC was independent of cellular glutathione. NAC strongly inhibited the uptake of all three metals in histologically different types of human cells, explaining its high chemoprotective potential. A loss of Cr(VI) accumulation by cells was caused by NAC-mediated extracellular reduction of chromate to membrane-impermeative Cr(III). Suppression of Co(II) uptake resulted from a rapid formation of Co(II)–NAC conjugates that were unable to enter cells. Our results demonstrate that NAC acts through more than one mechanism in preventing metal toxicity and its chemoprotective activity can be completely ROS-independent. Good clinical safety and effectiveness in Co(II) sequestration suggest that NAC could be useful in the prevention of tissue accumulation and toxic effects of Co ions released by cobalt–chromium hip prostheses.     

Molecular cloning and characterization of cat, gpx1 and Cu/Zn-sod genes in pengze crucian carp (Carassius auratus var. Pengze) and antioxidant enzyme modulation induced by hexavalent chromium in juveniles

Hexavalent chromium (Cr^6 +) is a common pollutant transient metal with high toxicity in the environment. The toxicological effects partly result from oxidative damage due to the production of excessive reactive oxygen species (ROS) in the reductive process of Cr^6 +. To explore the influence of ROS induced directly by Cr^6 + on the oxidative stress generation and antioxidant system, the full length cDNAs of antioxidant-related genes cat, gpx1 and Cu/Zn-sod were successfully acquired from pengze crucian carp first and analyzed. Furthermore, the mRNA expression of the antioxidant genes encompassing catalase (cat), copper/zinc superoxide dismutase (Cu/Zn-sod) and glutathione peroxidase (gpx1), antioxidant enzyme activities of CAT, SOD, and GPx and total protein content were further studied in the gill, intestine and liver of pengze crucian carp (Carassius auratus var. Pengze) juveniles upon acute exposure to Cr^6 + at concentrations of 0.1, 1.0, 10 and 100 mg/L for 4 days. Differential significant changes of the antioxidant enzymes and gene expression were observed in different tissues. The findings contribute to better understanding the antioxidant mechanisms induced by Cr^6 + and selecting the organic-specific sensitive biomarkers to monitor the safety of the aquatic ecosystem.