• 【希腊中部蒂瓦盆地地下水中的六价铬污染。】 复制标题 收藏 收藏
    DOI:10.1007/s00128-012-0831-4 复制DOI
    作者列表:Tziritis E,Kelepertzis E,Korres G,Perivolaris D,Repani S
    BACKGROUND & AIMS: :There is an increasing concern regarding elevated levels of Cr(VI) in the environment due to its higher mobility and toxicity compared to the trivalent form. Anomalous hexavalent chromium concentrations (up to 212 μg/L) were determined in irrigated groundwaters from the wider area of Thiva Basin (central Greece), frequently exceeding the permissible limit for human consumption (50 μg/L for total Cr). Based on the spatial distribution of Cr(VI) values, two groups of groundwater samples were distinguished, possibly reflecting different natural and/or anthropogenic factors that govern the levels of contamination. The first group is spatially located northwards of Thiva town and is consisted of concentrations that range from 13 to 212 μg/L (median 58 μg/L), while the second group is located near Mouriki village and Cr(VI) values range from <9 to 14 μg/L. The Cr(VI) chemical anomalies represent an important social problem because the agricultural products of this region are a major vegetable supply for Greece, bringing up the urgent need to evaluate the health effects associated with Cr(VI) exposure by ingesting the potentially contaminated foods.
    背景与目标: : 与三价形式相比,由于其更高的迁移率和毒性,环境中Cr(VI) 的水平升高引起了越来越多的关注。在来自锡瓦盆地 (希腊中部) 更广阔地区的灌溉地下水中,测定了六价铬的异常浓度 (最高212 μ g/L),经常超过人类食用的允许限值 (总Cr为50 μ g/L)。根据Cr(VI) 值的空间分布,区分了两组地下水样品,这可能反映了控制污染水平的不同自然和/或人为因素。第一组位于Thiva镇的北部,其浓度范围为13至212 μ g/L (中位数为58 μ g/L),而第二组位于Mouriki村附近,Cr(VI) 值范围为 <9至14 μ g/L。Cr(VI) 化学异常是一个重要的社会问题,因为该地区的农产品是希腊的主要蔬菜供应,因此迫切需要通过摄入可能受到污染的食物来评估与Cr(VI) 暴露相关的健康影响。
  • 【饲喂无机铬对冬季暴露的水牛犊牛 (Bubalus bubalis) 的生长性能,内分泌变量和能量代谢产物的影响。】 复制标题 收藏 收藏
    DOI:10.1007/s12011-013-9808-3 复制DOI
    作者列表:Kumar M,Kaur H,Tyagi AK,Kewalramani NJ,Mani V,Deka RS,Sharma VK,Chandra G,Dang AK
    BACKGROUND & AIMS: :We investigated the effect of chromium (Cr) supplementation on the growth performance, energy metabolites, and hormonal variation in winter-exposed buffalo calves. Twenty-four female buffalo calves were randomly allotted to four dietary treatments (n = 6) for a period of 120 days. Feeding regimen was the same in all the groups, except the animals in the four respective groups were additionally supplemented with 0.0, 0.5, 1.0, and 1.5 mg of Cr/kg DM in the form of CrCl3.6H2O. Calves were monitored daily for physiological variables and dry matter intake (DMI). Blood samples were collected at fortnightly intervals from each buffalo calves to measure concentrations of hormones (insulin, cortisol, and growth hormone), energy metabolites (glucose and non-esterified fatty acids), and plasma mineral levels. After 120 days of feeding trial, buffalo calves fed with Cr had lower (P < 0.05) circulating plasma concentrations of glucose, insulin, and cortisol hormones, whereas plasma thyroid hormone and non-esterified fatty acids concentrations were found similar (P > 0.05) among all the treatments. The results suggested that dietary Cr supplementation influenced plasma Cr levels without affecting the plasma concentrations of other trace minerals. However, physiological variables, nutrient intake, and growth performance of buffalo calves did not differ among all treatments (P > 005). In summary, the current study showed that supplementation of Cr at the level of 1.0 and 1.5 mg of Cr/kg DMI was more effective in improving glucose utilization by increasing potency of insulin hormone and reducing concentration of cortisol hormone. Results also suggested that supplemental Cr also improves blood plasma Cr levels.
    背景与目标: : 我们研究了补充铬 (Cr) 对冬季暴露的水牛犊牛的生长性能,能量代谢产物和激素变化的影响。24只雌性水牛被随机分配到四种饮食治疗 (n =   6) 中,为期120天。所有组的喂养方案都是相同的,除了四个相应组的动物另外补充了0.0、0.5、1.0和1.5 mg CrCl3.6H2O形式的Cr/kg DM。每天监测小牛的生理变量和干物质摄入量 (DMI)。每两周从每只水牛犊牛收集血液样本,以测量激素 (胰岛素,皮质醇和生长激素),能量代谢产物 (葡萄糖和非酯化脂肪酸) 和血浆矿物质水平的浓度。经过120天的喂养试验,饲喂Cr的水牛小牛的血浆葡萄糖,胰岛素和皮质醇激素的循环浓度较低 (p  <  0.05),而血浆甲状腺激素和非酯化脂肪酸的浓度在所有处理中相似 (p  >  0.05)。结果表明,饮食中添加Cr会影响血浆Cr水平,而不会影响其他微量矿物质的血浆浓度。然而,水牛犊牛的生理变量、营养摄入量和生长性能在所有处理之间没有差异 (p  >  005)。总而言之,当前的研究表明,通过增加胰岛素激素的效力和降低皮质醇激素的浓度,以1.0和1.5 mg Cr/kg DMI的水平补充Cr在改善葡萄糖利用方面更有效。结果还表明,补充Cr还可以改善血浆Cr水平。
  • 【急性暴露于庆大霉素,汞和铬后尿液和肾脏中肾损伤分子1和其他肾毒性生物标志物的比较。】 复制标题 收藏 收藏
    DOI:10.1093/toxsci/kfm260 复制DOI
    作者列表:Zhou Y,Vaidya VS,Brown RP,Zhang J,Rosenzweig BA,Thompson KL,Miller TJ,Bonventre JV,Goering PL
    BACKGROUND & AIMS: :Sensitive biomarkers are needed to detect kidney injury at the earliest stages. The objective of this study was to determine whether the appearance of kidney injury molecule-1 (Kim-1) protein ectodomain in urine and kidney injury molecule-1/hepatitis A viral cellular receptor-1 (Kim-1/Havcr1) gene expression in kidney tissue may be more predictive of renal injury after exposure to nephrotoxicants when compared to traditionally used biomarkers. Male Sprague-Dawley rats were injected with a range of doses of gentamicin, mercury (Hg; HgCl2), or chromium (Cr; K2Cr2O7). The results showed that increases in urinary Kim-1 and kidney Kim-1/Havcr1 gene expression paralleled the degree of severity of renal histopathology and were detected at lower doses of nephrotoxicants when compared to blood urea nitrogen (BUN), serum creatinine, and urinary N-acetyl-beta-D-glucosaminidase (NAG). In a time course study, urinary Kim-1 was elevated within 24 h after exposure to gentamicin (100 mg/kg), Hg (0.25 mg/kg), or Cr (5 mg/kg) and remained elevated through 72 h. NAG responses were nephrotoxicant dependent with elevations occurring early (gentamicin), late (Cr), or no change (Hg). At 72 h, after treatment with any of the three nephrotoxicants, there was increased Kim-1 immunoreactivity and necrosis involving approximately 50% of the proximal tubules; however, only urinary Kim-1 was significantly increased, while BUN, serum creatinine, and NAG were not different from controls. In rats treated with the hepatotoxicant galactosamine (1.1 mg/kg), serum alanine aminotransferase was increased, but no increase in urinary Kim-1 was observed. Urinary Kim-1 and kidney Kim-1/Havcr1 expression appear to be sensitive and tissue-specific biomarkers that will improve detection of early acute kidney injury following exposure to nephrotoxic chemicals and drugs.
    背景与目标: : 需要敏感的生物标志物在最早阶段检测肾损伤。这项研究的目的是确定尿液中肾损伤分子-1 (Kim-1) 蛋白胞外域的出现和肾损伤分子-1/甲型肝炎病毒细胞受体-1 (Kim-1/Havcr1) 基因在肾脏组织中的表达是否可能更预测暴露于肾毒性药物后的肾损伤与传统使用的生物标志物相比。雄性Sprague-Dawley大鼠注射了一系列剂量的庆大霉素,汞 (Hg; HgCl2) 或铬 (Cr; K2Cr2O7)。结果表明,与血尿素氮 (BUN),血清肌酐和尿N-乙酰-β-D-氨基葡萄糖苷酶 (NAG) 相比,尿Kim-1和肾Kim-1/Havcr1基因表达的增加与肾组织病理学的严重程度平行,并且在较低剂量的肾毒物下检测到。在时间过程研究中,暴露于庆大霉素 (100 mg/kg),Hg (0.25 mg/kg) 或Cr (5 mg/kg) 后24小时内尿Kim-1升高,并在72小时内保持升高。NAG反应依赖于肾毒性,早期 (庆大霉素),晚期 (Cr) 或无变化 (Hg) 发生升高。在72小时,用三种肾毒物中的任何一种治疗后,涉及大约50% 个近端小管的Kim-1免疫反应性和坏死增加; 然而,只有尿Kim-1显着增加,而BUN,血清肌酐和NAG与对照组没有差异。在用肝毒性半乳糖胺 (1.1 mg/kg) 治疗的大鼠中,血清丙氨酸氨基转移酶升高,但未观察到尿Kim-1增加。尿Kim-1和肾脏Kim-1/Havcr1表达似乎是敏感的和组织特异性的生物标志物,将改善暴露于肾毒性化学物质和药物后的早期急性肾损伤的检测。
  • 【植物病原真菌菌核菌的铬耐受性,氧化应激反应,形态特征和FTIR研究。】 复制标题 收藏 收藏
    DOI:10.1007/s12223-016-0489-0 复制DOI
    作者列表:Rafi S,Shoaib A,Awan ZA,Rizvi NB,Nafisa,Shafiq M
    BACKGROUND & AIMS: :Sclerotium rolfsii is one of the most destructive fungal plant pathogens that can infect over 500 plants and can adapt to diverse environmental conditions. The present research work was carried out to evaluate the impact of both hexa- and trivalent chromium (Cr) on growth, morphology, enzymatic characteristics, and metal accumulation in S. rolfsii under laboratory conditions. Experiments were performed in both malt extract broth and agar growth medium amended with six different concentrations (10, 20, 40, 60, 80, and 100 ppm) of each Cr(III) and Cr(VI) ions inoculated with fungus and incubated for 6-7 days at 25 ± 3 °C. In broth medium, the total protein content was declined and activities of antioxidant enzymes were increased with an increase in metal concentrations. Lower concentrations (10 ppm) of the metal ions stimulated the growth of fungus and higher concentrations (60-100) inhibited it. The Fourier transform infrared spectroscopy (FTIR) assessment showed hydroxyl, carboxyl, and amine groups as major metal binding sites. In agar medium, tolerance index was decreased up to 0.56 at 10-80 ppm of Cr(III) and up to 0.62 at 10-60 ppm of Cr(VI). Considerable modifications were observed in hyphal and sclerotial morphology with an increase in concentration of metal ions. The current study concluded that interference of Cr with growth and physiological process of S. rolfsii could affect its infection level on its host plant. This study provides important information regarding cultivation of susceptible plant varieties in Cr-polluted soil as evidenced by pathogen growth up to 50 ppm of Cr(III) and Cr(VI) ions.
    背景与目标: : 菌核菌是最具破坏性的真菌植物病原体之一,可以感染500多种植物,并可以适应各种环境条件。进行了本研究工作,以评估六价铬和三价铬 (Cr) 在实验室条件下对S. rolfsii的生长,形态,酶促特性和金属积累的影响。在用六种不同浓度 (10、20、40、60、80和100 ppm) 的每种Cr(III) 和Cr(VI) 离子接种真菌并在25 ± 3 °C下孵育6-7天的麦芽提取物肉汤和琼脂生长培养基中进行实验。在肉汤培养基中,随着金属浓度的增加,总蛋白含量下降,抗氧化酶的活性增加。较低浓度 (10 ppm) 的金属离子刺激真菌生长,较高浓度 (60-100) 抑制真菌生长。傅里叶变换红外光谱 (FTIR) 评估显示羟基,羧基和胺基是主要的金属结合位点。在琼脂培养基中,耐受性指数在10-80ppm的Cr(III) 下降低至0.56,在10-60ppm的Cr(VI) 下降低至0.62。随着金属离子浓度的增加,在菌丝和硬化形态上观察到相当大的变化。目前的研究结论是,Cr对S. rolfsii的生长和生理过程的干扰可能会影响其对寄主植物的感染水平。这项研究提供了有关在Cr污染的土壤中易感植物品种种植的重要信息,病原体生长高达50 ppm的Cr(III) 和Cr(VI) 离子就证明了这一点。
  • 【钴-细胞色素c. II.磁共振波谱和构象跃迁。】 复制标题 收藏 收藏
    DOI:10.1021/bi00687a004 复制DOI
    作者列表:Dickinson LC,Chien JC
    BACKGROUND & AIMS: :Between pH approximately 4 and 10 cobaltocytochrome c (Cocyt-c) gives an electron paramagnetic resonance (EPR) spectrum with g parallel = 2.035, g the perpendicular = 2.223, CoA PARALLEL = 61.4 G, CoA the perpendicular = 49.8 G, NA parallel = 15.3 G, and NA THE PERPENDICULAR = 12.5 G. Comparisons with the EPR spectra of deoxycobaltomyoglobin, deoxycobaltohemoglobin, and model compounds and together with other evidence showed cobaltocytochrome c to have Met-80 and His-18 as its axial ligands. The protons of these ligands are seen as resonances shifted by the ring-current field of the porphyrin in the 300-MHZ 1H nuclear magnetic resonance (NMR) spectra of cobalticytochrome c (Cocyt-c+). The methyl and gamma-methylene protons of Met-80 in this molecule occupy positions with respect to heme c which are somewhat different from those in ferrocytochrome c. The 1H NMR spectra also showed that the methyl groups of Leu-32, Ile-75, Thr-63, thioether bridges, and the porphyrin ring in the cobalt protein are in the same state as in native enzyme; the same is also true for Tyr-59, His-26, and His-33 and also possibly Tyr-67, Tyr-74, and Phe-82. Above pH 11, Cocyt-c is converted to a five-coordinated form having g parallel = 2.026, g the perpendicular = 2.325, CoA parallel = 80 G, CoA the perpendicular approximately 10 G, NA parallel = 17.5 G, and NA the perpendicular not resolved. Below pH 1.0 the EPR spectrum of Cocyt-c is also five-coordinated with g parallel = 2.014, g the perpendicular = 2.359, CoA parallel = 93.8 G, and CoA the perpendicular = 38.8 G. The axial ligands in the alkaline and the acidic forms of Cocyt-c are His-18 and Met-80, respectively. New prominent proton resonance peaks are observed in cobalt-cytochrome c which are either absent or weak in native cytochrome c. These are situated at 3.0, 1.7, and 1.44 ppm, attributable, respectively, to the epsilon-CH2, DELTA-CH2 + beta-CH2, and gamma-CH2 of lysyl residues in random-coil-peptides. From the areas of these peaks, it is estimated that one-two lysyl residues in Cocyt-c have been modified; four-five lysyl residues in Cocyt-c+ have been modified. These alterations of surface charged groups are probably responsible for the lowered reactivity of Cocyt-c with cytochrome oxidase and the lack of reactivity of Cocyt-c+ with several cytochrome reductase systems.
    背景与目标: : 在大约4到10的pH之间,钴细胞色素c (Cocyt-c) 给出了电子顺磁共振 (EPR) 光谱,g平行 = 2.035,g垂直 = 2.223,CoA平行 = 61.4G,CoA垂直 = 49.8G,NA平行 = 15.3G,和NA的垂线 = 12.5G。与脱氧钴氧球蛋白,脱氧钴血红蛋白和模型化合物的EPR光谱进行比较,并与其他证据一起表明,钴细胞色素c具有Met-80和His-18作为其轴向配体。在钴基铬c (Cocyt-c) 的300 MHZ 1H核磁共振 (NMR) 光谱中,这些配体的质子被视为卟啉的环电流场偏移的共振。该分子中Met-80的甲基和 γ-亚甲基质子相对于血红素c占据的位置与铁细胞色素c中的位置有些不同。1H NMR光谱还显示Leu-32的甲基,Ile-75,Thr-63,硫醚桥,钴蛋白中的卟啉环与天然酶中的卟啉环处于相同状态; Tyr-59,His-26和His-33以及Tyr-67,Tyr-74和Phe-82也是如此。在ph11以上,Cocyt-c转化为具有g平行 = 2.026、g垂直 = 2.325、CoA平行 = 80G、CoA垂直约10G、NA平行 = 17.5G、NA垂直未解析的五配位形式。在pH 1.0以下,Cocyt-c的EPR光谱也是五配位的,g平行 = 2.014,g垂直 = 2.359,CoA平行 = 93.8G,CoA垂直 = 38.8G。Cocyt-c的碱性和酸性形式的轴向配体分别为他-18和Met-80。在钴-细胞色素c中观察到新的显著质子共振峰,其在天然细胞色素c中不存在或弱。这些峰位于3.0、1.7和1.44 ppm,分别归因于随机线圈肽中赖氨酰残基的epsilon-CH2、DELTA-CH2 + beta-CH2和gamma-CH2。从这些峰的区域来看,估计Cocyt-c中的一两个赖氨酰残基已被修饰; Cocyt-c中的四个-五个赖氨酰残基已被修饰。表面带电基团的这些变化可能是导致Cocyt-c与细胞色素氧化酶的反应性降低以及Cocyt-c与几种细胞色素还原酶系统缺乏反应性的原因。
  • 【通过共同限制表面中的硒和内层中的钴来促进MoS2上的氢释放。】 复制标题 收藏 收藏
    DOI:10.1038/s41467-020-17199-0 复制DOI
    作者列表:Zheng Z,Yu L,Gao M,Chen X,Zhou W,Ma C,Wu L,Zhu J,Meng X,Hu J,Tu Y,Wu S,Mao J,Tian Z,Deng D
    BACKGROUND & AIMS: :The lack of highly efficient, inexpensive catalysts severely hinders large-scale application of electrochemical hydrogen evolution reaction (HER) for producing hydrogen. MoS2 as a low-cost candidate suffers from low catalytic performance. Herein, taking advantage of its tri-layer structure, we report a MoS2 nanofoam catalyst co-confining selenium in surface and cobalt in inner layer, exhibiting an ultra-high large-current-density HER activity surpassing all previously reported heteroatom-doped MoS2. At a large current density of 1000 mA cm-2, a much lower overpotential of 382 mV than that of 671 mV over commercial Pt/C catalyst is achieved and stably maintained for 360 hours without decay. First-principles calculations demonstrate that inner layer-confined cobalt atoms stimulate neighbouring sulfur atoms while surface-confined selenium atoms stabilize the structure, which cooperatively enable the massive generation of both in-plane and edge active sites with optimized hydrogen adsorption activity. This strategy provides a viable route for developing MoS2-based catalysts for industrial HER applications.
    背景与目标: : 缺乏高效,廉价的催化剂严重阻碍了电化学析氢反应 (HER) 用于制氢的大规模应用。MoS2作为一种低成本候选产品,催化性能低下。在此,利用其三层结构,我们报告了一种MoS2纳米foam催化剂,将硒共约束在表面和钴在内层,表现出超高的大电流密度HER活性,超过了所有先前报道的杂原子掺杂MoS2。在1000  ma   cm-2的大电流密度下,在商用Pt/C催化剂上实现了比671  mV低得多的382  mV的过电位,并稳定地保持360小时而没有衰减。第一性原理计算表明,内层约束的钴原子会刺激相邻的硫原子,而表面约束的硒原子会稳定结构,从而可以协同产生大量的面内和边缘活性位点,并具有优化的氢吸附活性。该策略为开发用于工业HER应用的MoS2-based催化剂提供了可行的途径。
  • 【通过IFNgamma-ELISPOT分析和铬释放分析定量外周血中抗原反应性T细胞: 一项四中心比较试验。】 复制标题 收藏 收藏
    DOI:10.1016/s0022-1759(00)00257-x 复制DOI
    作者列表:Scheibenbogen C,Romero P,Rivoltini L,Herr W,Schmittel A,Cerottini JC,Woelfel T,Eggermont AM,Keilholz U
    BACKGROUND & AIMS: :The ELISPOT assay is increasingly being used for the monitoring of the induction of antigen-reactive T cells in cancer vaccination trials. In order to evaluate the reliability of T cell frequency analysis with the ELISPOT assay, a comparative study was performed in four European laboratories. Six samples from healthy subjects were analyzed for the frequency of influenza-reactive CD8+ T cells in peripheral blood mononuclear cells (PBMC) by IFNgamma-ELISPOT assay. In addition, one laboratory determined cytotoxic T cell precursor (CTL) frequencies in these samples by limiting dilution chromium-release assay (LDA), and three laboratories performed a variant of the LDA, the multiple microculture assay (MMA). Consistent frequencies of influenza peptide-reactive T cells were obtained with the ELISPOT assay in all four laboratories. The numbers detected by ELISPOT assay correlated closely with those determined by LDA. In contrast, the frequencies obtained with the MMA differed considerably and showed little correlation with the other two assays. This study shows that it is possible to use the ELISPOT assay to determine with reliability antigen-reactive T cells in a multicenter setting. We suggest that this assay may be suitable for monitoring cancer vaccine trials.
    背景与目标: : ELISPOT测定法越来越多地用于监测癌症疫苗接种试验中抗原反应性T细胞的诱导。为了评估使用ELISPOT测定法进行T细胞频率分析的可靠性,在四个欧洲实验室进行了比较研究。通过IFNgamma-ELISPOT测定法分析了来自健康受试者的六个样本的外周血单核细胞 (PBMC) 中流感反应性CD8 T细胞的频率。此外,一个实验室通过限制稀释铬释放测定 (LDA) 确定了这些样品中的细胞毒性T细胞前体 (CTL) 频率,三个实验室进行了LDA的变体,即多重微培养测定 (MMA)。在所有四个实验室中,通过ELISPOT测定法获得了一致的流感肽反应性T细胞频率。ELISPOT测定法检测到的数字与LDA测定的数字密切相关。相反,用MMA获得的频率差异很大,并且与其他两种测定几乎没有相关性。这项研究表明,可以使用ELISPOT测定法在多中心环境中可靠地确定抗原反应性T细胞。我们建议该测定法可能适用于监测癌症疫苗试验。
  • 【新分离的放线菌长链链霉菌ld22的铬 [Cr(VI)] 生物吸附特性。】 复制标题 收藏 收藏
    DOI:10.1007/s13205-014-0237-6 复制DOI
    作者列表:Latha S,Vinothini G,Dhanasekaran D
    BACKGROUND & AIMS: :The present work demonstrates the heavy metal resistance and detoxification of Cr(VI) by the probiotic actinobacterial cultures isolated from chicken and goat feces. The actinobacterial isolates were screened for heavy metal resistance by qualitative, semiquantitative assays and Cr(VI) biosorption was determined by analytical techniques such as atomic absorption spectrophotometry and Fourier transform infrared spectrometry (FT-IR). All the tested actinobacterial isolates (n = 20) showed resistance toward K2Cr2O7, NiCl2, ZnCl2, CuSO4 and PbNO3 at 20 mg L-1 concentration. The maximum tolerance concentration values were found to be 200-250 mg L-1 for K2Cr2O7, 100-250 mg L-1 for PbNO3 and <50-250 mg L-1 for NiCl2, ZnCl2 and CuSO4. Among the five tested heavy metals, Cr(VI) was resisted by 95 % of the tested actinobacterial cultures up to 250 mg L-1 concentration; particularly, the isolate LD22 exhibited a high degree of tolerance to all the tested heavy metals. Thus, the isolate was justifiably chosen for Cr(VI) biosorption study and the biosorption efficacy was found maximum at 100 mg L-1 of metal ion concentration (3 g L-1 of biomass dosage and pH 7.0). FT-IR spectrum revealed the chemical interactions between the hydroxyl, amine and carboxyl groups of the biomass and the metal ions. On the basis of phenotypic, physiological, biochemical and molecular characteristics the isolate LD22 was identified as Streptomyces werraensis LD22 (JX524481) which could be used to develop a biosorbent for adsorbing Cr(VI) metal ions.
    背景与目标: : 本工作证明了从鸡和山羊粪便中分离出的益生菌放线菌培养物对Cr(VI) 的重金属抗性和解毒作用。通过定性,半定量分析筛选放线菌分离株的重金属抗性,并通过原子吸收分光光度法和傅里叶变换红外光谱法 (ft-ir) 等分析技术测定Cr(VI) 的生物吸附。所有测试的放线菌分离株 (n = 20) 在20 mg L-1浓度下均显示出对K2Cr2O7,NiCl2,ZnCl2,CuSO4和PbNO3的抗性。发现最大耐受浓度值对于K2Cr2O7为200-250 mg L-1,对于PbNO3为100-250 mg L-1,对于NiCl2,ZnCl2和cuso4为 <50-250 mg L-1。在五种测试的重金属中,Cr(VI) 被95% 测试的放线菌培养物抵抗高达250 mg L-1浓度; 特别地,分离物LD22对所有测试的重金属表现出高度的耐受性。因此,合理地选择分离物进行Cr(VI) 生物吸附研究,发现在L-1 100 mg金属离子浓度 (3g L-1生物质剂量和pH 7.0) 时,生物吸附效力最大。Ft-ir光谱揭示了生物质的羟基,胺和羧基与金属离子之间的化学相互作用。根据表型,生理,生化和分子特征,将分离物LD22鉴定为werraensis链霉菌LD22 (JX524481),可用于开发吸附Cr(VI) 金属离子的生物吸附剂。
  • 【碳化钨-钴作为体外遗传毒性试验中的纳米颗粒参考阳性对照。】 复制标题 收藏 收藏
    DOI:10.1093/toxsci/kft222 复制DOI
    作者列表:Moche H,Chevalier D,Barois N,Lorge E,Claude N,Nesslany F
    BACKGROUND & AIMS: :With the increasing human exposure to nanoparticles (NP), the evaluation of their genotoxic potential is of significant importance. However, relevance for NP of the routinely used in vitro genotoxicity assays is often questioned, and a nanoparticulate reference positive control would therefore constitute an important step to a better testing of NP, ensuring that test systems are really appropriate. In this study, we investigated the possibility of using tungsten carbide-cobalt (WC-Co) NP as reference positive control in in vitro genotoxicity assays, including 2 regulatory assays, the mouse lymphoma assay and the micronucleus assay, and in the Comet assay, recommended for the toxicological evaluation of nanomedicines by the French Agency of Human Health Products (Afssaps). Through these assays, we were able to study different genetic endpoints in 2 cell types commonly used in regulatory genotoxicity assays: the L5178Y mouse lymphoma cell line and primary cultures of human lymphocytes. Our results showed that the use of WC-Co NP as positive control in in vitro genotoxicity assays was conceivable, but that different parameters have to be considered, such as cell type and treatment schedule. L5178Y mouse lymphoma cells did not provide satisfactory results in the 3 performed tests. However, human lymphocytes were more sensitive to genotoxic effects induced by WC-Co NP, particularly after a 24-h treatment in the in vitro micronucleus assay and after a 4-h treatment in the in vitro Comet assay. Under such conditions, WC-Co could be used as a nanoparticulate reference positive control in these assays.
    背景与目标: : 随着人类对纳米颗粒 (NP) 的暴露增加,对其遗传毒性潜力的评估非常重要。然而,通常使用的体外遗传毒性测定与NP的相关性经常受到质疑,因此,纳米颗粒参考阳性对照将构成更好地测试NP的重要步骤,从而确保测试系统确实合适。在这项研究中,我们研究了在体外遗传毒性试验中使用碳化钨-钴 (WC-Co) NP作为参考阳性对照的可能性,包括2项调节试验,小鼠淋巴瘤试验和微核试验,以及在彗星试验中,法国人类健康产品局 (Afssaps) 推荐用于纳米药物的毒理学评估。通过这些测定,我们能够研究调节性遗传毒性测定中常用的2种细胞类型的不同遗传终点: L5178Y小鼠淋巴瘤细胞系和人类淋巴细胞的原代培养物。我们的结果表明,在体外遗传毒性测定中使用WC-Co NP作为阳性对照是可以想象的,但是必须考虑不同的参数,例如细胞类型和治疗时间表。L5178Y小鼠淋巴瘤细胞在3次进行的测试中均未提供令人满意的结果。然而,人类淋巴细胞对WC-Co NP诱导的遗传毒性作用更为敏感,尤其是在体外微核试验中进行24小时处理后以及在体外彗星试验中进行4小时处理后。在这种条件下,WC-Co可以在这些测定中用作纳米颗粒参考阳性对照。
  • 【母体铬状态对雌性老年小鼠后代脂质代谢的影响及其分子机制。】 复制标题 收藏 收藏
    DOI:10.1042/BSR20160362 复制DOI
    作者列表:Zhang Q,Sun X,Xiao X,Zheng J,Li M,Yu M,Ping F,Wang Z,Qi C,Wang T,Wang X
    BACKGROUND & AIMS: :Maternal malnutrition leads to the incidence of metabolic diseases in offspring. The purpose of this project was to examine whether maternal low chromium could disturb normal lipid metabolism in offspring, altering adipose cell differentiation and leading to the incidence of lipid metabolism diseases, including metabolic syndrome and obesity. Female C57BL mice were given a control diet (CD) or a low chromium diet (LCD) during the gestational and lactation periods. After weaning, offspring was fed with CD or LCD. The female offspring were assessed at 32 weeks of age. Fresh adipose samples from CD-CD group and LCD-CD group were collected. Genome mRNA were analysed using Affymetrix GeneChip Mouse Gene 2.0 ST Whole Transcript-based array. Differentially expressed genes (DEGs) were analysed based on gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis database. Maternal low chromium irreversibly increased offspring body weight, fat-pad weight, serum triglyceride (TG) and TNF-α. Eighty five genes increased and 109 genes reduced in the offspring adipose of the maternal low chromium group. According to KEGG pathway and String analyses, the PPAR signalling pathway may be the key controlled pathway related to the effect of maternal low chromium on female offspring. Maternal chromium status have long-term effects of lipid metabolism in female mice offspring. Normalizing offspring diet can not reverse these effects. The potential underlying mechanisms are the disturbance of the PPAR signalling pathway in adipose tissue.
    背景与目标: : 产妇营养不良导致后代代谢性疾病的发生。本课题的目的是研究母体低铬是否会干扰后代正常的脂质代谢,改变脂肪细胞的分化并导致脂质代谢疾病 (包括代谢综合征和肥胖) 的发生。在妊娠和哺乳期,对雌性C57BL小鼠进行对照饮食 (CD) 或低铬饮食 (LCD)。断奶后,用CD或LCD喂养后代。在32周龄时对雌性后代进行评估。收集cd-cd组和lcd-cd组的新鲜脂肪样品。使用Affymetrix GeneChip小鼠基因2.0 ST全转录物基阵列分析基因组mRNA。基于基因本体论 (GO) 和京都基因和基因组百科全书 (KEGG) 途径分析数据库对差异表达基因 (DEGs) 进行分析。母体低铬不可逆地增加了后代体重,脂肪垫重量,血清甘油三酸酯 (TG) 和TNF-α。母体低铬组子代脂肪的85个基因增加,109个基因减少。根据KEGG途径和字符串分析,PPAR信号途径可能是与母体低铬对雌性后代影响有关的关键控制途径。母体铬状态对雌性小鼠后代的脂质代谢具有长期影响。使后代饮食正常化不能逆转这些影响。潜在的潜在机制是脂肪组织中PPAR信号通路的紊乱。
  • 【血浆铬水平与新诊断的2型糖尿病的负相关: 一项病例对照研究。】 复制标题 收藏 收藏
    DOI:10.3390/nu9030294 复制DOI
    作者列表:Chen S,Jin X,Shan Z,Li S,Yin J,Sun T,Luo C,Yang W,Yao P,Yu K,Zhang Y,Cheng Q,Cheng J,Bao W,Liu L
    BACKGROUND & AIMS: :Chromium has long been known as an enhancer of insulin action. However, the role of chromium in the development of type 2 diabetes mellitus (T2DM) in humans remains controversial. The current study aimed to examine the associations of plasma chromium levels with T2DM and pre-diabetes mellitus (pre-DM). We conducted a case-control study involving 1471 patients with newly diagnosed T2DM, 682 individuals with newly diagnosed pre-DM, and 2290 individuals with normal glucose tolerance in a Chinese population from 2009 to 2014. Plasma chromium was measured by inductively coupled plasma mass spectrometry. Plasma chromium levels were lower in the T2DM and pre-DM groups than in the control group (median: 3.68 μg/L, 3.61 μg/L, 3.97 μg/L, respectively, p < 0.001). After adjustment for potential confounding factors, the odds ratios (95% confidence interval) for T2DM across increasing quartiles of plasma chromium levels were 1 (referent), 0.67 (0.55-0.83), 0.64 (0.51-0.79), and 0.58 (0.46-0.73), respectively (p for trend <0.001). The corresponding odds ratios (95% confidence interval) for pre-DM were 1 (referent), 0.70 (0.54-0.91), 0.67 (0.52-0.88), and 0.58 (0.43-0.78), respectively (p for trend < 0.001). Our results indicated that plasma chromium concentrations were inversely associated with T2DM and pre-DM in Chinese adults.
    背景与目标: : 铬长期以来被认为是胰岛素作用的增强剂。然而,铬在人类2型糖尿病 (T2DM) 发展中的作用仍存在争议。当前的研究旨在检查血浆铬水平与T2DM和糖尿病前期 (pre-DM) 的关系。我们进行了一项病例对照研究,纳入了1471例新诊断的T2DM患者,682例新诊断的糖尿病前期患者和2290例葡萄糖耐量正常的中国人群2009年2014年。通过电感耦合等离子体质谱法测量等离子体铬。T2DM组和pre-DM组的血浆铬水平低于对照组 (中位数: 3.68 μ g/L,3.61 μ g/L,3.97 μ g/L,p <0.001)。在调整了潜在的混杂因素后,血浆铬水平增加的四分位数中T2DM的比值比 (95% 置信区间) 为1 (参照),0.67 (0.55-0.83),0.64 (0.51-0.79) 和0.58 (0.46-0.73),分别 (p表示趋势 <0.001)。前DM的相应优势比 (95% 置信区间) 分别为1 (参照) 、0.70 (0.54-0.91) 、0.67 (0.52-0.88) 和0.58 (0.43-0.78) (p表示趋势 <0.001)。我们的结果表明,中国成年人血浆铬浓度与T2DM和前DM呈负相关。
  • 【钴对小学生心血管系统参数的影响。】 复制标题 收藏 收藏
    DOI:10.1007/s10517-013-2141-1 复制DOI
    作者列表:Svyatova NV,Sitdikov FG,Egerev ES
    BACKGROUND & AIMS: :High incidence of cobalt deficiency (89%) was found in 7-8-year-old girls residents of the Republic of Tatarstan. Significant correlations were revealed between parameters of physical development and cardiovascular system and hair cobalt content. These data suggest that positive balance of cobalt is essential for normal growth and development of child's body and function of the cardiovascular system.
    背景与目标: : 在ta斯坦共和国的7-8岁女孩居民中发现钴缺乏症 (89%) 的高发生率。身体发育和心血管系统参数与头发钴含量之间存在显着相关性。这些数据表明,钴的正平衡对于儿童身体的正常生长和发育以及心血管系统的功能至关重要。
  • 【超累积Alyssum murale对钴的金属存储机制与对镍的金属存储机制不同。】 复制标题 收藏 收藏
    DOI:10.1111/j.1469-8137.2007.02134.x 复制DOI
    作者列表:Tappero R,Peltier E,Gräfe M,Heidel K,Ginder-Vogel M,Livi KJ,Rivers ML,Marcus MA,Chaney RL,Sparks DL
    BACKGROUND & AIMS: :The nickel (Ni) hyperaccumulator Alyssum murale has been developed as a commercial crop for phytoremediation/phytomining Ni from metal-enriched soils. Here, metal co-tolerance, accumulation and localization were investigated for A. murale exposed to metal co-contaminants. A. murale was irrigated with Ni-enriched nutrient solutions containing basal or elevated concentrations of cobalt (Co) or zinc (Zn). Metal localization and elemental associations were investigated in situ with synchrotron X-ray microfluorescence (SXRF) and computed-microtomography (CMT). A. murale hyperaccumulated Ni and Co (> 1000 microg g(-1) dry weight) from mixed-metal systems. Zinc was not hyperaccumulated. Elevated Co or Zn concentrations did not alter Ni accumulation or localization. SXRF images showed uniform Ni distribution in leaves and preferential localization of Co near leaf tips/margins. CMT images revealed that leaf epidermal tissue was enriched with Ni but devoid of Co, that Co was localized in the apoplasm of leaf ground tissue and that Co was sequestered on leaf surfaces near the tips/margins. Cobalt-rich mineral precipitate(s) form on leaves of Co-treated A. murale. Specialized biochemical processes linked with Ni (hyper)tolerance in A. murale do not confer (hyper)tolerance to Co. A. murale relies on a different metal storage mechanism for Co (exocellular sequestration) than for Ni (vacuolar sequestration).
    背景与目标: : 镍 (Ni) 超积累的阿利苏姆·穆拉勒 (Alyssum murale) 已被开发为一种商业作物,用于从富含金属的土壤中进行植物修复/植物化镍。在这里,研究了暴露于金属共污染物的A. murale的金属共耐受性,积累和定位。A. murale用富含镍的营养液灌溉,该营养液含有基础或高浓度的钴 (Co) 或锌 (Zn)。使用同步加速器x射线微荧光 (SXRF) 和计算机微断层扫描 (CMT) 原位研究了金属定位和元素缔合。A. murale从混合金属体系中累积的Ni和Co (> 1000微克 (-1) 干重)。锌没有过度蓄积。升高的Co或Zn浓度不会改变Ni的积累或定位。SXRF图像显示叶片中Ni分布均匀,并且Co在叶尖/边缘附近优先定位。CMT图像显示,叶片表皮组织富含Ni,但不含Co,Co位于叶地组织的质膜中,Co被隔离在尖端/边缘附近的叶片表面。在共同处理的A. murale的叶片上形成富钴矿物沉淀。与A. murale中的Ni (超) 耐受性相关的专门生化过程不赋予Co (超) 耐受性。A. murale对Co (胞外隔离) 的金属存储机制与对Ni (液泡隔离) 的金属存储机制不同。
  • 【铬污染的辅助绿色修复。】 复制标题 收藏 收藏
    DOI:10.1016/j.jenvman.2017.04.094 复制DOI
    作者列表:Gheju M,Balcu I
    BACKGROUND & AIMS: :The effects of application of two anions commonly found in subsurface environments, phosphate (PO43-) and sulfate (SO42-), on hexavalent chromium (Cr(VI)) uptake and translocation by Zea mays, were investigated using pot-culture experiments. The two anions were tested as potential agents to mobilize Cr(VI) from polluted soil (50, 75 and 100 mg kg-1 dw) at a dose of 16.7 mmol kg-1. Metal uptake from soil to roots and subsequent transfer to shoots was discussed in terms of bioconcentration factor (BCF) and translocation factor (TF). The overall order of BCFs and TFs which resulted from this study was: PO43- > H2O > SO42-; in the same time, metal concentration in plants tissues decreased in the order: root > stem > leaf. The present study suggests that PO43- may be used as an environmentally compatible alternative to non-biodegradable synthetic chelants, to enhance the efficiency of Cr(VI) phytoextraction with Z. mays.
    背景与目标: : 使用盆栽实验研究了在地下环境中常见的两种阴离子磷酸盐 (PO43-) 和硫酸盐 (SO42-) 对玉米吸收和转运六价铬 (Cr(VI)) 的影响。测试了这两种阴离子作为潜在的试剂,以16.7 mmol kg-1的剂量从污染的土壤 (50,75和100 mg kg-1 dw) 中动员Cr(VI)。根据生物浓缩因子 (BCF) 和易位因子 (TF) 讨论了金属从土壤到根部的吸收以及随后向芽的转移。本研究产生的bcf和TFs的总体顺序为: PO43- > H2O > SO42-; 同时,植物组织中的金属浓度按以下顺序降低: 根> 茎> 叶。本研究表明,PO43-可以用作不可生物降解的合成螯合剂的环境相容性替代品,以提高Z. mays提取Cr(VI) 植物的效率。
  • 【比较Zucker瘦肉,Zucker肥胖和Zucker糖尿病性脂肪大鼠的组织金属浓度以及补充铬对组织金属浓度的影响。】 复制标题 收藏 收藏
    DOI:10.1007/s12011-012-9565-8 复制DOI
    作者列表:Staniek H,Rhodes NR,Di Bona KR,Deng G,Love ST,Pledger LA,Blount J,Gomberg E,Grappe F,Cernosek C,Peoples B,Rasco JF,Krejpcio Z,Vincent JB
    BACKGROUND & AIMS: :Diabetes results in several metabolic changes, including alterations in the transport, distribution, excretion, and accumulation of metals. While changes have been examined in several rat models of insulin resistance and diabetes, the metal ion concentrations in the tissues of Zucker lean, Zucker obese (an insulin resistance and early stage diabetes model), and Zucker diabetic fatty (ZDF, a type 2 diabetes model) have not previously been examined in detail. The concentration of Cu, Zn, Fe, Mg, and Ca were examined in the liver, kidney, heart and spleen, and Cr concentration in the liver and kidney of these rats were examined. Zucker obese rats have a reduction in the concentration of Cu, Zn, Fe, Mg in the liver compared to ZDF and/or lean Zucker rats, presumably as a result of the increased fat content of the liver of the obese rats. ZDF rats have increased concentrations of kidney Cu compared to the lean rats, while kidney Ca concentrations are increased in the Zucker obese rats. Spleen Fe concentrations are decreased in Zucker obese rats compared to the lean rats. No effects on metal concentrations in the heart were observed between the lean, obese, and ZDF rats, and no effects on Cr concentrations were identified. Cr(III) complexes have previously been shown to have beneficial effects on the signs of insulin resistance in Zucker obese and ZDF rats. The effects of daily gavage administration of chromium picolinate ([Cr(pic)(3)]) (1 mg Cr/kg body mass), CrCl(3) (1 mg Cr/kg body mass), and Cr3 ([Cr(3)O(propionate)(6)(H(2)O)(3)](+)) (33 μg and 1 mg Cr/kg body mass) on metal concentrations in these tissues were examined. Treatment with CrCl(3) and Cr3, but not [Cr(pic)(3)], at 1 mg Cr/kg resulted in a statistically significant accumulation of Cr in the kidney of lean and obese but not ZDF rats but resulted in lowering the elevated levels of kidney Cu in ZDF rats, suggesting a beneficial effect on this symptom of type 2 diabetes.
    背景与目标: 糖尿病会导致多种代谢变化,包括运输,分布,排泄和金属积累的改变。虽然已在几种胰岛素抵抗和糖尿病大鼠模型中检查了变化,但Zucker瘦肉,Zucker肥胖 (胰岛素抵抗和早期糖尿病模型) 和Zucker糖尿病脂肪 (ZDF,2型糖尿病) 组织中的金属离子浓度以前尚未详细检查。检查了这些大鼠的肝脏,肾脏,心脏和脾脏中Cu,Zn,Fe,Mg和Ca的浓度,并检查了这些大鼠的肝脏和肾脏中的Cr浓度。与ZDF和/或瘦Zucker大鼠相比,Zucker肥胖大鼠的肝脏中Cu,Zn,Fe,Mg的浓度降低,这可能是由于肥胖大鼠肝脏脂肪含量增加的结果。与瘦大鼠相比,ZDF大鼠的肾脏Cu浓度增加,而Zucker肥胖大鼠的肾脏Ca浓度增加。与瘦大鼠相比,Zucker肥胖大鼠的脾脏Fe浓度降低。在瘦弱,肥胖和ZDF大鼠之间未观察到对心脏中金属浓度的影响,并且未发现对Cr浓度的影响。先前已显示Cr(III) 复合物对Zucker肥胖和ZDF大鼠的胰岛素抵抗迹象具有有益作用。日灌胃给药吡啶甲酸铬 ([Cr(pic)(3)]) (1 mg Cr/kg体重),CrCl(3) (1 mg Cr/kg体重),和Cr3 ([Cr(3)O (丙酸)(6)(H(2)O)(3)]()) (33μg和1 mg Cr/kg体重) 检查了这些组织中的金属浓度。以1 mg Cr/kg的CrCl(3) 和Cr3 (但不包括 [Cr(pic)(3)]) 治疗,导致瘦弱和肥胖但ZDF大鼠肾脏中Cr的统计学显着积累,但ZDF大鼠肾脏Cu水平降低,提示对2型糖尿病的这种症状有有益作用。

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