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911.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):944-953
A new series of four biologically active triazole derived Schiff base ligands (L1–L4) and their cobalt(II), nickel(II), copper(II) and zinc(II) complexes (1–16) have been synthesized and characterized. The ligands were prepared by the condensation reaction of 3-amino-5-methylthio-1H-1,2,4-triazole with chloro-, bromo- and nitro-substituted 2-hydroxybenzaldehyde in an equimolar ratio. The antibacterial and antifungal bioactivity data showed the metal(II) complexes to be more potent antibacterial and antifungal than the parent Schiff bases against one or more bacterial and fungal species. 相似文献
912.
913.
Mosses, covering about 23,000 species of all land plants in the world, have been widely used as an indicator of heavy metal pollution in many studies. A crucial part in these researches is to regularize the adsorption capacities of different moss species obtained from different regions to objectively compare the pollution levels. In this study, we have first analyzed the lead adsorption capacities of six different moss species by means of using column filled with Amberlite XAD-2000 resin method. The adsorption capacities of the studied six mosses are found in descending order as Eurhynchium striatum, Hypnum cupressiforme, Pleurozium schreberi, Eurhynchium striatulum, Homalothecium sericeum and Thuidium tamariscinum. Then, we have regularized the Pb adsorption levels for the moss species obtained from different regions along one of the important coast highway in Turkey, namely Sarp-Samsun highway, with respect to the determined adsorption capacities. 相似文献
914.
915.
福建漳州菜园土壤重金属污染评价及防治 总被引:9,自引:0,他引:9
调查福建省漳州市菜园土壤重金属Cd、Pb、Hg、Cr及非金属有害元素As含量,并采用单项污染指数法和综合污染指数法进行评价。结果表明,以福建土壤背景值为评价标准,漳州市部分菜园土壤受到重金属污染,单项污染指数的顺序为Cd(2.39) >Hg(2.00) >Pb(1.40) >Cr(0.63) >As(0.57),污染元素主要为Cd、Pb、Hg,其中Cd、Hg为中度污染;综合污染指数为1.75,属轻度污染。而以土壤环境质量二级标准为评价标准,其综合污染指数为0.14,污染等级为未受污染。 相似文献
916.
A. Khadjavi A. Notarpietro F. Mannu A. Pantaleo E. Ferru P. Destefanis D. Fontana F. Turrini 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Bladder cancer has the peculiarity of shedding neoplastic cells and their components in urine representing a valuable opportunity to detect diagnostic markers. Using a semi-quantitative method we previously demonstrated that the levels of Tyr-phosphorylated proteins (TPPs) are highly increased in bladder cancer tissues and that soluble TPPs can also be detected in patient's urine samples. Although the preliminary evaluation showed very promising specificity and sensitivity, insufficient accuracy and very low throughput of the method halted the diagnostic evaluation of the new marker. To overcome this problem we developed a quantitative methodology with high sensitivity and accuracy to measure TPPs in urine.Methods
The Immobilized Metal Affinity Chromatography (IMAC) was miniaturized in a 96 well format. Luminescence, visible and infrared fluorescence antibody-based detection methods were comparatively evaluated.Results
Due to their low abundance we evidenced that both phosphoprotein enrichment step and very sensitive detection methods are required to detect TPPs in urine samples. To pursue high throughput, reproducibility and cost containment, which are required for bladder cancer screening programs, we coupled the pre-analytical IMAC procedure with high sensitive detection phases (infrared fluorescence or chemiluminescence) in an automated platform.Conclusions
A high throughput method for measuring with high sensitivity TPP levels in urine samples is now available for large clinical trial for the establishment of the diagnostic and predictive power of TPPs as bladder cancer marker.General significance
The new assay represents the first quantitative and high throughput method for the measurement of TPPs in urine. 相似文献917.
C. Shiny Matilda S.T. Mannully V.P. Rao C. Shanthi 《Letters in applied microbiology》2021,72(5):517-525
Bacteria survive metal stress by several mechanisms and metal binding is one such mechanism which has been screened in the present study to investigate the survival strategies of metal resistant bacteria. The production of siderophores, a metal chelating agent, was detected by chrome azurol S agar assay. The changes in cell wall studied by analysing the peptidoglycan and teichoic acid content indicated an increase in the cell wall content. Evaluation of morphological and physiological alterations like cell size, granularity analysed by SEM and flow cytometry analysis revealed an increase in cell size and granularity respectively. The transformation of phosphates monitored by 31P NMR analysis indicated the presence of inorganic phosphate. Based on the cell wall changes and the 31P NMR analysis, the surface charge of the organism was studied by zeta potential which displayed a difference at pH7. 相似文献
918.
Genetic improvement of heavy metal tolerance in plants by transfer of the yeast metallothionein gene (CUP1) 总被引:15,自引:0,他引:15
Hasegawa Isao Terada Emiko Sunairi Michio Wakita Hajime Shinmachi Fumie Noguchi Akira Nakajima Mutsuyasu Yazaki Jinya 《Plant and Soil》1997,196(2):277-281
Cauliflower (Brassica oleracea var. botrytis) tolerates treatment with 25 µM CdCl2 for eight days, but is killed by that with a 50 µM concentration. However, even 15 µM CdCl2 is toxic in the presence of 1 mM L-buthionine sulfoximine (BSO), suggesting the presence of a Cd-inducible phytochelatin and its involvement in Cd-tolerance in cauliflower. To develop heavy metal-tolerant transgenic plants, we ligated the structural gene of yeast metallothionein gene (CUP1) downstream of CaMV35S promoter and introduced the fused gene into cauliflower. A Cd-tolerant transgenic cauliflower was selected, which grew well in the presence of 400 µM or less Cd, whereas the non-transformed cauliflower tolerated only up to 25 µM Cd. The transgenic cauliflower accumulated more Cd, especially in the upper leaves, than the non-transformed plant.In conclusion, by transfer of the yeast metallothionein gene into cauliflower increased Cd-tolerance and Cd-accumulating ability can be conferred to the plant. 相似文献
919.
Marzieh Ghollasi Khosro Khajeh Nasrin Mollania Shekufeh Zareian Hossein Naderi-Manesh 《Biologia》2008,63(6):1051-1056
An amylopullulanase (L14-APU) from an Iranian thermophilic bacterium was purified and the effect of acarbose, as a general inhibitor of α-amylases, on pullulan and starch hydrolysis catalyzed by L14-APU was investigated. The inhibition is a competitive type whereas inhibition constants for pullulan and starch are 99 μM
and 72 μM, respectively. Investigation of the reaction rate in a system contains competitive substrates and the inhibition
type of acarbose in presence of different substrates suggests that L14-APU possesses only one active site for two activities. The analysis of metal ions and other reagents effects has shown that
Ca2+, Mg2+, Mn2+ and Co2+ enhanced both activities of the enzyme while N-bromosuccinimide treatment leads to the complete inactivation of the enzyme.
The enzyme activity increased in the presence of low concentration of SDS as a surfactant. 相似文献
920.
A new Schiff base of gossypol with 3,6,9-trioxo-decylamine (GSTB) forms stable complexes with monovalent cations. This process of complex formation was studied by electrospray ionization mass spectrometry, (1)H-NMR and FTIR spectroscopy, and the PM5 (parametric method 5) semiempirical method. It is found that GSTB forms 1 : 1 and 1 : 2 complexes with Li(+) and Na(+) and 1 : 1 complexes with K(+), Rb(+), or Cs(+) cations and exists in all these complexes in the enamine-enamine tautomeric form. Moreover, within these complexes only Li(+) cations can fluctuate between the oxygen atoms of trioxo-alkyl chains. All other cations are strongly localized. In the complex of GSTB with two protons localized on the N atoms of the Schiff base, the imine-imine tautomeric form is realized. The complexes of the Schiff base with K(+), Rb(+), or Cs(+) cations are the 1 : 1 type with the oxygen atoms of the trioxo-alkyl chains, as well as the O(1)H or O(1')H group coordinating the cation. The structures of the complexes are calculated by the PM5 semiempirical method and discussed. 相似文献