Zinc status does not affect aluminum deposition in tissues of rats

To examine whether zinc deficiency would increase the toxicity of dietary aluminum, weanling, male Sprague-Dawley rats were fed purified diets containing either 2 or 30 mg Zn/kg diet, with or without 500 mg Al/kg diet for 28 d. Individually pair-fed rats were fed the 30 mg Zn/kg diet with or without added aluminum to control for inanition secondary to zinc deficiency. Rats fed the 2 μg Zn/kg diet showed evidence of zinc deficiency, including anorexia, growth retardation, and depressed concentrations of zinc in tibias and livers. Zinc deficiency did not significantly increase the concentrations of aluminum in the tibias, livers, kidneys, or regions of the brain examined (cerebrum, cerebellum, midbrain, and hippocampus). Inclusion of aluminum in the diet did not alter aluminum concentrations in the various tissues. Under the conditions of this study, zinc deficiency did not result in greater sensitivity to dietary aluminum exposure.     

The uptake of zinc by erythrocytes under near-physiological conditions

The in vitro uptake of zinc by erythrocytes was measured under near-physiological conditions, using⁶⁵Zn as a radioactive tracer. Because of the presence of serum albumin—a strong zinc ligand—a low concentration of medium free zinc was maintained. Under these conditions a high-affinity carrier for zinc transport over the cell membrane was identified. With human erythrocytes, a Michaelis constant (K _m ) of 0.2 nM with respect to free medium zinc was measured and aV _max of 4.5 nmoles Zn transported per h/g dry wt. TheK _m for medium Zn increases when the size of the internal erythrocytic Zn pool is augmented, whereasV _max remains virtually unchanged. A model to explain this phenomenon is proposed. It is suggested that this phenomenon could underlie observations, confirmed here, that the in vitro uptake of Zn by animal erythrocytes depends on the Zn status of the animal.     

Effect of exchangeable aluminium on the reduction of potato scab

The severity of the incidence of the fungal disease, potato scab, varies with different soil groups at the same soil pH. At a soil pH of 5.3, potato scab is easily controlled in soils of western Hokkaido (soil group A) by simply decreasing soil pH, but in soils from eastern Hokkaido (soil group B) it is not so easily controlled. The difference appears to be due to higher levels and exchangeable aluminium in Group A.Addition of sufficient aluminium or ferrous sulfate to a group B soil decreased the incidence of potato scab in a field experiment. Higher levels of aluminium sulfate depressed crop production. It is concluded that aluminium ions control the incidence of potato scab in acid soils. It is suggested that, in soils with low exchange acidity Y1, potato scab can be controlled by adding sufficient aluminium to increase their exchange acidity Y1 to above 7–8.     

Iron content of sediment and phosphate adsorption properties

Phosphorus can occur in sediments in different forms and accordingly its availability varies. The distinction between the phosphorus fractions is made with two chemical extraction methods; an ammonium oxalate-oxalic acid extraction and an extraction according to Hieltjes & Lijklema (1980).The iron and aluminum liberated with the ammonium oxalate-oxalic acid extraction method is linearly correlated (r ² = 0.73) with the phosphorus liberated in the first two steps of the Hieltjes and Lijklema extraction by: P = 0.035 (Fe + Al) + 0.001 (P, Fe and Al in mmol g^–1).The iron and aluminum (hydr)oxides are very important fractions in the sediment adsorption capacity for phosphorus. The phosphorus sorption capacity (PSC) is 0.080 mol P (mol (Fe + Al))^–1 and the adsorption constant (k) is 11.9 µmol P l^–1. Here it is assumed that iron and aluminum (hydr)oxide have the same affinity for phosphorus.     

Evaluating the Madeiran wheat germplasm for aluminum resistance using aluminium-induced callose formation in root apices as a marker

Aluminum (Al) resistance of 57 Madeiran wheat cultivars was evaluated using callose content in root tips and root elongation as markers. Al induced callose formation was a very sensitive indicator of Al damage detecting wide range of genotypic differences existing in the Madeiran wheat germplasm. A weak, yet positive correlation (R²=0.285, P<0.05) between callose content and root elongation was found.     

Expression of human peripheral cannabinoid receptor for structural studies

Human peripheral-type cannabinoid receptor (CB2) was expressed in Escherichia coli as a fusion with the maltose-binding protein, thioredoxin, and a deca-histidine tag. Functional activity and structural integrity of the receptor in bacterial protoplast membranes was confirmed by extensive binding studies with a variety of natural and synthetic cannabinoid ligands. E. coli membranes expressing CB2 also activated cognate G-proteins in an in vitro coupled assay. Detergent-solubilized receptor was purified to 80%-90% homogeneity by affinity chromatography followed by ion-exchange chromatography. By high-resolution NMR on the receptor in DPC micelles, it was determined that purified CB2 forms 1:1 complexes with the ligands CP-55,940 and anandamide. The receptor was successfully reconstituted into phosphatidylcholine bilayers and the membranes were deposited into a porous substrate as tubular lipid bilayers for structural studies by NMR and scattering techniques.     

Catalytic enantioselective addition of indoles to arylnitroalkenes: an effective route to enantiomerically enriched tryptamine precursors

A new valuable catalytic protocol for the preparation of synthetically useful beta-indolyl nitro compounds bearing benzhydryl stereocenters is presented. The combined use of catalytic amounts of a commercially available chiral [SalenAlCl] complex and pyridine allowed, for the Friedel-Crafts alkylation reaction of indoles with aromatic nitro-olefins to be carried out in good yields and enantioselectivity (up to 63% ee).     

中亚热带不同母质发育森林土壤磷组分特征及其影响因素

本研究以福建三明砂岩和花岗岩发育的米槠林土壤和杉木林土壤为对象,分析土壤磷组分、铁铝氧化物、微生物生物量以及磷酸酶活性等指标,研究母质和森林类型对土壤磷组分的影响程度和机制。结果表明: 母质和森林类型显著影响土壤不同磷组分含量。总体上,砂岩发育土壤全磷含量、活性无机/有机磷、中等活性无机/有机磷以及惰性磷含量均显著高于花岗岩发育土壤,并且砂岩发育米槠林土壤活性有机磷含量、中等活性无机/有机磷以及惰性磷含量显著高于砂岩发育杉木林土壤,而花岗岩发育米槠林与杉木林土壤磷组分的含量差异不显著。花岗岩发育的2种森林土壤酸性磷酸酶(ACP)活性显著高于砂岩,而砂岩发育米槠林土壤微生物生物量碳(MBC)和微生物生物量磷(MBP)显著高于砂岩发育杉木林土壤。土壤不同磷组分的含量与土壤不同形态铁铝氧化物含量、MBP、MBC呈显著正相关,而与土壤pH、ACP呈显著负相关,表明土壤母质和森林类型可能主要通过土壤铁铝氧化物赋存形态、ACP、MBP等生物及非生物因子影响中亚热带森林土壤磷组分分配特征。     

Life Cycle Energy and Greenhouse Gas Emissions of Automobiles Using Aluminum in China

Transportation is a major part of energy consumption and greenhouse gas (GHG) emissions. Aluminum (Al) as a light metal can reduce vehicle weight, energy consumption, and pollutant emissions, but Al production is energy intensive. The main contents of this study are the following: (1) create the life cycle inventory of Al parts based on the energy background in China and (2) evaluate the energy savings and GHG reduction for the vehicle when steel parts are replaced by Al parts. Although there is a considerable reduction in energy consumption of per tonne Al in China owing to continuing development of process technology in recent years, energy consumption is higher than the world average level and European level. Over the vehicle's life cycle driving of 200,000 kilometers, the vehicle was found to avoid 1,447 to 1,590 liters of gasoline consumption when six typical steel parts were replaced by Al parts. Based on the current technology, the breakeven distance was calculated, resulting in a net energy benefit to use the lightweight Al parts compared with steel parts. A sensitivity analysis was conducted to show different energy savings by considering secondary weight reduction and different driving distance. The results indicate that weight reduction by using Al is quite effective to reduce the energy consumption and GHG of transportation.     

Comparative studies on the interactions of baicalein and Al(III)–baicalein complex with human serum albumin

A new potential drug aluminum(III)–baicalein complex (ALBC) was synthesized and characterized. The binding mechanisms of baicalein (BC) and ALBC to human serum albumin (HSA) under simulative physiological conditions were investigated, in order to understand the pharmacokinetics of BC and ALBC. Fluorescence spectroscopy results suggested that the binding level of BC is higher than that of ALBC. Results of UV–vis, synchronous fluorescence, 3D fluorescence, circular dichroism and Fourier transform infrared spectroscopic analyses consistently demonstrated that the conformation of HSA was altered when bound to BC or ALBC. The distance between HSA as a donor and BC (or ALBC) as an acceptor was determined via fluorescence resonance energy transfer. The results of competitive experiments and molecular docking studies indicated that BC was located in site I (subdomain IIA) on HSA and that ALBC was bound to HSA mainly within site II (subdomain IIIA). Copyright © 2015 John Wiley & Sons, Ltd.