制革污泥林业利用场水域的鳑鲏鱼外周血红细胞微核监测

制革污泥施入林地后,检测小流域地表水、土壤渗出水对鳑鲏鱼(Rhodeus sinensis)外周血红细胞微核的诱变.结果表明:在实验范围内,没有诱发鳑鲏鱼血红细胞微核率增高,制革污泥林业利用系统是安全的;但鲜制革污泥浸出水可诱发鳑鲏鱼外周血红细胞微核率增高,故制革污泥如不加任何处理而随意堆放,会对坏境造成污染.     

Inhibition of TRPC4 channel activity in colonic myocytes by tricyclic antidepressants disrupts colonic motility causing constipation

Tricyclic antidepressants (TCAs) have been used to treat depression and were recently approved for treating irritable bowel syndrome (IBS) patients with severe or refractory IBS symptoms. However, the molecular mechanism of TCA action in the gastrointestinal (GI) tract remains poorly understood. Transient receptor potential channel canonical type 4 (TRPC4), which is a Ca²⁺‐permeable nonselective cation channel, is a critical regulator of GI excitability. Herein, we investigated whether TCA modulates TRPC4 channel activity and which mechanism in colonic myocytes consequently causes constipation. To prove the clinical benefit in patients with diarrhoea caused by TCA treatment, we performed mechanical tension recording of repetitive motor pattern (RMP) in segment, electric field stimulation (EFS)‐induced and spontaneous contractions in isolated muscle strips. From these recordings, we observed that all TCA compounds significantly inhibited contractions of colonic motility in human. To determine the contribution of TRPC4 to colonic motility, we measured the electrical activity of heterologous or endogenous TRPC4 by TCAs using the patch clamp technique in HEK293 cells and murine colonic myocytes. In TRPC4‐overexpressed HEK cells, we observed TCA‐evoked direct inhibition of TRPC4. Compared with TRPC4‐knockout mice, we identified that muscarinic cationic current (mI _cat) was suppressed through TRPC4 inhibition by TCA in isolated murine colonic myocytes. Collectively, we suggest that TCA action is responsible for the inhibition of TRPC4 channels in colonic myocytes, ultimately causing constipation. These findings provide clinical insights into abnormal intestinal motility and medical interventions aimed at IBS therapy.     

Cr Localization and Speciation in Roots of Chromate Fed Helianthus annuus L. Seedlings Using Synchrotron Techniques

In order to gain knowledge on the potential use of Helianthus annuus L. for the remediation of Cr(VI) polluted waters, hydroponics experiments were set up to determine Cr uptake and tolerance in different Cr(VI)-sulfate conditions, and Cr biotransformations. Results indicated that Cr(VI) promoted seed germination, and plant tolerance was higher at younger plant stages. Cr uptake was dependent on sulfate concentrations. The highest Cr levels in roots and shoots (13,700 and 2,500 mg kg^–1dry weight (DW), respectively) were obtained in 1 mM sulfate. The lowest Cr uptake in roots (10,600 mg kg^–1DW) was observed in seedlings treated with no sulfate. In shoots, Cr concentration was of 1,500 mg kg^–1DW for the 1 mM sulfate treatment, indicating a different level of interaction between chromate and sulfate in both tissues. For the first time, using micro X-ray florescence (μXRF), we demonstrated Cr reaches the root stele and is located in the walls of xylem vessels. Bulk and micro X-ray Absorption Near-Edge Structure (μXANES) results showed that Cr in the roots is mostly in the form of Cr(III) phosphate (80%), with the remainder complexed to organic acids. Our results suggest this plant species may serve for Cr(VI) rhizofiltration purposes.     

Quantitative assessment of neurochemical changes in a rat model of long-term alcohol consumption as detected by in vivo and ex vivo proton nuclear magnetic resonance spectroscopy

The aim of present study was to quantitatively investigate the neurochemical profile of the frontal cortex region in a rat model of long-term alcohol consumption, by using in vivo proton magnetic resonance spectroscopy (¹H-MRS) at 4.7 T and ex vivo¹H high-resolution magic angle spinning (HR-MAS) technique at 11.7 T. Twenty male rats were divided into two groups and fed a liquid diet for 10 weeks. After 10 weeks, in vivo¹H MRS spectra were acquired from the frontal cortex brain region. After in vivo¹H MRS experiments, all animals were sacrificed and 20 frontal cortex tissue samples were harvested. All tissue examinations were performed with the 11.7 T HR-MAS spectrometer and high-resolution spectra were acquired. The in vivo and ex vivo spectra were quantified as absolute metabolite concentrations and normalized ratios of total signal-intensity (i.e., metabolites_Norm), respectively. The absolute quantifications of in vivo spectra showed significantly higher glycerophosphocholine plus phosphocholine (GPC + PCh) and lower myo-inositol (mIns) concentrations in ethanol-treated rats compared to controls. The quantifications of ex vivo spectra showed significantly higher PCh_Norm, Cho_Norm and tCho_Norm, and lower GPC_Norm and mIns_Norm ratio levels in ethanol-treated rats compared to controls. Our findings suggest that reduced mIns concentrations caused by the long-term alcohol consumption may lead to hypo-osmolarity syndrome and astrocyte hyponatremia. In addition, increased choline-containing compound concentrations may reflect an increased cell turnover rate of phosphatidylcholine and other phospholipids, indicating an adaptive mechanism. Therefore, these results might be utilized as key markers in chronic alcohol intoxication metabolism.     

The effect of sulfur-containing nitrogen fertilizers on the elemental composition of celery (Apium graveolens) grown on a polluted marsh soil

Summary In order to investigate elemental composition of celery, and to quantify the influence of sulfur-containing N-fertilizers on the trace element uptake, a field trial with celery was carried out on marsh soil polluted with municipal wastes. The research yielded the following results:Compared to leaves at harvest time, bulbs showed significantly lower concentrations of Mo, S and Sb, but higher contents of B, Br and Cr and Cu. Since the acidifying effect of the fertilizers was suppressed by the free calcium carbonate in the soil, no significant changes in concentrations of cationic trace elements were detected in plants fertilized with ammonium sulfate compared to those which received urea or calcium ammonium nitrate. On the other hand, in these plants the conspicuous increase in total sulfur was accompanied by a significant decrease in concentrations of up to 30% for B, Br and Sb, 50% for As, 60% for Se and 80% for Mo.According to these results, in plant production on contaminated soils certain plant parts may be marketable due to their low tendency to accumulate toxic elements, and furthermore it may be feasible to reduce the contents of some of these elements in plants by the use of sulfur-containing fertilizers.     

Globotriaosylceramide is correlated with oxidative stress and inflammation in Fabry patients treated with enzyme replacement therapy

Fabry disease is an X-linked inborn error of glycosphingolipid catabolism due to deficient activity of α-galactosidase A that leads to accumulation of the enzyme substrates, mainly globotriaosylceramide (Gb3), in body fluids and lysosomes of many cell types. Some pathophysiology hypotheses are intimately linked to reactive species production and inflammation, but until this moment there is no in vivo study about it. Hence, the aim of this study was to investigate oxidative stress parameters, pro-inflammatory cytokines and Gb3 levels in Fabry patients under treatment with enzyme replacement therapy (ERT) and finally to establish a possible relation between them. We analyzed urine and blood samples of patients under ERT (n = 14) and healthy age-matched controls (n = 14). Patients presented decreased levels of antioxidant defenses, assessed by reduced glutathione (GSH), glutathione peroxidase (GPx) activity and increased superoxide dismutase/catalase (SOD/CAT) ratio in erythrocytes. Concerning to the damage to biomolecules (lipids and proteins), we found that plasma levels of malondialdehyde (MDA) and protein carbonyl groups and di-tyrosine (di-Tyr) in urine were increased in patients. The pro-inflammatory cytokines IL-6 and TNF-α were also increased in patients. Urinary Gb3 levels were positively correlated with the plasma levels of IL-6, carbonyl groups and MDA. IL-6 levels were directly correlated with di-Tyr and inversely correlated with GPx activity. This data suggest that pro-inflammatory and pro-oxidant states occur, are correlated and seem to be induced by Gb3 in Fabry patients.     

Growth stimulatory effect of Ochrobactrum intermedium and Bacillus cereus on Vigna radiata plants

AIMS: This study assessed the plant growth-promoting ability of the bacterial strains Ochrobactrum intermedium (isolate CrT-1) and Bacillus cereus (isolate S-6). METHODS AND RESULTS: Two chromium resistant bacterial strains isolated from chromium-contaminated wastewater and soils were identified as O. intermedium CrT-1 and B. cereus S-6. These strains were inoculated on seeds of mungbean Vigna radiata var NM-92, which were germinated and grown under chromate salts (300 microg ml(-1) of CrCl(3)or K(2)CrO(4)). The data show that Cr(VI) was more toxic because of its better availability to plants roots when compared with Cr(III). The major part of Cr(VI) supplied to the seedlings was reduced to Cr(III) in the rhizosphere by the bacterial strains, thus lowering the toxicity of chromium to seedlings. CONCLUSIONS: Strains have significant Cr(VI) resistance and reduction potential and have ability to enhance mungbean plant growth under chromium stress. SIGNIFICANCE AND IMPACT OF THE STUDY: These strains could be utilized for the growth of economically important cash crops as well as for the bioremediation of chromium-polluted soils.     

Mechanical Properties and Microstructure of Bionic Non-Smooth Stainless Steel Surface by Laser Multiple Processing

Laser multiple processing, i.e. laser surface texturing and then Laser Shock Processing (LSP), is a new surface processingtechnology for the preparation of bionic non-smooth surfaces. Based on engineering bionics, samples of bionic non-smoothsurfaces of stainless steel 0Crl 8Ni9 were manufactured in the form of reseau structure by laser multiple processing. The mechanicalproperties (including microhardness, residual stress, surface roughness) and microstructure of the samples treated bylaser multiple processing were compared with those of the samples without LSP The results show that the mechanical propertiesof these samples by laser multiple processing were clearly improved in comparison with those of the samples without LSP Themechanisms underlying the improved surface microhardness and surface residual stress were analyzed, and the relations betweenhardness, comnressive residual stress and roughness were also presented.     

Plant seed extract assisted,eco-synthesized C-ZnO nanoparticles: Characterization,chromium(VI) ion adsorption and kinetic studies

This report attempts to elucidate the potential of plant seed extract assisted synthesis of graphite-based zinc oxide nanoparticles (C-ZnO NPs) towards removal of chromium(VI) ions from water samples. The graphite-based zinc oxide (C-ZnO) composites were characterized using thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The C-ZnO nanocomposites have found to remove chromium from the sample through an adsorption process. The sensitivity of chromium removal through adsorption is found to be in the range of 40 to 240 mg. The adsorption behaviour was found to be fitting with Langmuir isotherm model and the adsorption reaction follows pseudo second-order kinetics.     

Cr3+,Cr6+及其复合污染对狐尾藻的毒害作用

采用急性毒害水培法,研究比较了不同浓度的Cr⁶⁺,Cr³⁺单一及复合处理对狐尾藻不定根和叶片生理生态的影响。实验结果表明:1)当浓度≤1mg·L^-1时,Cr³⁺对不定根的生长表现出促进作用,数量增加,长度增长。而Cr⁶⁺及复合处理系列对不定根却表现出强烈的抑制作用,在高浓度时甚至使其生长停止;2)叶绿素含量在1mg·L^-1Cr³⁺培养液中达到最大值,随Cr⁶⁺及复合处理浓度的增大而呈连续下降趋势;3)可溶性蛋白含量在三种处理方式中都表现出抛物线形式,复合处理组在1mg·L^-1时使蛋白含量出现高峰;4)细胞内超氧阴离子产生速率,膜脂过氧化水平与污染浓度和时间呈显著正相关;5)随着处理浓度的增加,SOD,OD,CAT活性先升后降,但其高峰分别出现在处理浓度为1mg·L^-1,10mg·L^-1,5mg·L^-1时;6)研究证实,Cr⁶⁺,Cr³⁺复合处理对狐尾藻的毒害作用较单一Cr⁶⁺,Cr³⁺显著,二者表现出协同作用,而其中Cr⁶⁺毒性大于Cr³⁺。