共查询到20条相似文献,搜索用时 15 毫秒
1.
BackgroundTrace elements exhibit essential functions in many physiological processes. Thus, for research focusing on trace element homeostasis and metabolism analytical methods allowing for multi-element analyses are fundamental. Small sample amounts may be a big challenge in trace element analyses especially if also other end points want to be addressed in the same sample. Therefore, the aim of the present study was to examine trace elements (iron, copper, zinc, and selenium) in murine liver tissue prepared by a RIPA buffer-based lyses method.Methods and resultsAfter centrifugation, lysates and pellets were obtained and trace elements were analyzed with TXRF in liver lysates. The results were compared to that obtained by a standard microwave-assisted acidic digestion with subsequent ICP-MS/MS analysis of the same liver tissue, liver lysates, and remaining pellets. In addition, trace element concentrations, determined in murine serum with both methods, were compared. For serum samples, both TXRF and ICP-MS/MS provide similar and highly correlating results. Furthermore, in liver lysate samples prepared with RIPA buffer, comparable trace element concentrations were measured by TXRF as with the standard digestion technique and ICP-MS/MS. Only marginal amounts of trace elements were detected in the pellets.ConclusionTaken together, the results obtained by the present study indicate that the RIPA buffer-based method is suitable for sample preparation for trace element analyses via TXRF, at least for the here investigated murine liver samples. 相似文献
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Telgmann L Holtkamp M Künnemeyer J Gelhard C Hartmann M Klose A Sperling M Karst U 《Metallomics : integrated biometal science》2011,3(10):1035-1040
A simple and rapid method to determine gadolinium (Gd) concentrations in urine and blood plasma samples by means of total reflection X-ray fluorescence (TXRF) was developed. With a limit of detection (LOD) of 100 μg L(-1) in urine and 80 μg L(-1) in blood plasma and a limit of quantification (LOQ) of 330 μg L(-1) in urine and 270 μg L(-1) in blood plasma, it allows analyzing urine samples taken from magnetic resonance imaging (MRI) patients during a period of up to 20 hours after the administration of Gd-based MRI contrast agents by means of TXRF. By parallel determination of the urinary creatinine concentration, it was possible to monitor the excretion kinetics of Gd from the patient's body. The Gd concentration in blood plasma samples, taken immediately after an MRI examination, could be determined after rapid and easy sample preparation by centrifugation. All measurements were validated with inductively coupled plasma mass spectrometry (ICP-MS). TXRF is considered to be an attractive alternative for fast and simple Gd analysis in human body fluids during daily routine in clinical laboratories. 相似文献
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Padoin Susana de Freitas Victor Hugo Cleto Daniele Aparecida Maia Zeffa Aline Campos Nakamura Fábio Yuzo Andrello Avacir Casanova de Paula Ramos Solange 《Biological trace element research》2020,193(1):73-80
Biological Trace Element Research - The aim of this study was to monitor the circulating and salivary ion concentrations by total reflection X-ray fluorescence (TXRF) in futsal players submitted to... 相似文献
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Acclimation to environmental changes involves a modification of the expressed proteome and metabolome. The reproductive advantage associated with the higher fitness that acclimation provides to the new conditions more than compensates for the costs of acclimation. To exploit such an advantage, however, the duration of the perturbation must be sufficiently long relative to the growth rate. Otherwise, a selective pressure may exist in favour of responses that minimize changes in carbon allocation and resource use and do not require reversal of the acclimation after the perturbation ceases (compositional homeostasis). We hypothesize that the choice between acclimation and homeostasis depends on the duration of the perturbation relative to the length of the cell cycle. To test this hypothesis, we cultured the green alga Tetraselmis suecica at two growth rates and subjected the cultures to three environmental perturbations. Carbon allocation was studied with Fourier transform infrared (FTIR) spectroscopy; elemental stoichiometry was investigated by total reflection X‐ray fluorescence (TXRF) spectroscopy. Our data confirmed that growth rate is a crucial factor for C allocation in response to external changes, with a higher degree of compositional homeostasis in cells with lower growth rate. 相似文献
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* The analysis of metal distribution in Imperata cylindrica, a perennial grass isolated from the banks of Tinto River (Iberian Pyritic Belt), an extreme acidic environment with high content in metals, has shown a remarkable accumulation of iron. This property has been used to study iron speciation and its distribution among different tissues and structures of the plant. * Mossbauer (MS) and X-ray diffraction (XRD) were used to determine the iron species, scanning electron microscopy (SEM) to locate iron biominerals among plant tissue structures, and energy-dispersive X-ray microanalysis (EDAX), X-ray fluorescence (TXRF) and inductively coupled plasma emission spectroscopy (ICP-MS) to confirm their elemental composition. * The MS spectral analysis indicated that iron accumulated in this plant mainly as jarosite and ferritin. The presence of jarosite was confirmed by XRD and the distribution of both minerals in structures of different tissues was ascertained by SEM-EDAX analysis. * The convergent results obtained by complementary techniques suggest a complex iron management system in I. cylindrica, probably as a consequence of the environmental conditions of its habitat. 相似文献
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Lucía Tapia Miriam Suazo Christian Hödar Verónica Cambiazo Mauricio González 《Biometals》2003,16(1):169-174
With this work, we have determined the cellular content of Cu, Fe and Zn in different cell lines, by using total reflection X-ray fluorescence spectrometry (TXRF). In addition, we examined whether cellular exposure to 100 moles l–1 of Cu-His modifies the intracellular content and distribution of these trace metals. Our results indicate that all the cell lines displayed the same pattern of relative intracellular abundance of trace metals (Cu相似文献
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Sabatini SE Rocchetta I Nahabedian DE Luquet CM Eppis MR Bianchi L Ríos de Molina Mdel C 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2011,154(4):391-398
The aim of this work was to study the oxidative stress effects and histological alterations caused by dietary copper on the filter-feeding freshwater mussel Diplodon chilensis. Bivalves were fed during 6 weeks with the green algae Scenedesmus vacuolatus previously exposed to copper. Metal concentration in algae cultures and bivalve digestive gland was measured by TXRF. A maximum accumulation of 0.49 μg Cu/mg protein was detected at week 6. Also at this week, the hepatosomatic index (HSI) showed the highest decrease (50%) in response to Cu exposure. SOD and GST activities were significantly increased at weeks 4, 5 and 6, reaching an activity on average 50% higher than in controls for GST. CAT activity and GSH increased significantly at weeks 5 and 6. Despite this response, oxidative damage measured as TBARS and carbonyl groups contents increased significantly at weeks 4, 5 and 6, respectively. Digestive tubule and duct atrophy and cell-type replacement in treated mussels were observed by histological studies. The presence of intracellular rhodanine-positive granules, suggests copper accumulation in intracellular vacuoles of digestive cells. 相似文献
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Victor G. Mihucz Florian Meirer Zsófia Polgári Andrea Réti Giancarlo Pepponi Dieter Ingerle Norbert Szoboszlai Christina Streli 《Journal of biological inorganic chemistry》2016,21(2):241-249
Fast- and slow-proliferating human adenocarcinoma colorectal cells, HT-29 and HCA-7, respectively, overloaded with transferrin (Tf), Fe(III) citrate, Fe(III) chloride and Fe(II) sulfate were studied by synchrotron radiation total-reflection X-ray spectrometry (TXRF), TXRF-X-ray absorption near edge structure (TXRF-XANES), and micro-X-ray fluorescence imaging to obtain information on the intracellular storage of overloaded iron (Fe). The determined TfR1 mRNA expression for the investigated cells correlated with their proliferation rate. In all cases, the Fe XANES of cells overloaded with inorganic Fe was found to be similar to that of deliquescent Fe(III) sulfate characterized by a distorted octahedral geometry. A fitting model using a linear combination of the XANES of Tf and deliquescent Fe(III) sulfate allowed to explain the near edge structure recorded for HT-29 cells indicating that cellular overload with inorganic Fe results in a non-ferritin-like fast Fe storage. Hierarchical cluster analysis of XANES spectra recorded for Fe overloaded HT-29 and HCA-7 cells was able to distinguish between Fe treatments performed with different Fe species with a 95 % hit rate, indicating clear differences in the Fe storage system. Micro-X-ray fluorescence imaging of Fe overloaded HT-29 cells revealed that Fe is primarily located in the cytosol of the cells. By characterizing the cellular Fe uptake, Fe/S content ratios were calculated based on the X-ray fluorescence signals of the analytes. These Fe/S ratios were dramatically lower for HCA-7 treated with organic Fe(III) treatments suggesting dissimilarities from the Tf-like Fe uptake. 相似文献
9.
《Biochimica et Biophysica Acta (BBA)/General Subjects》2023,1867(2):130279
BackgroundEarly-stage detection of subclinical obesity-driven systemic changes is a challenging area of medical diagnostics, where the most popular existing measures – such as body mass index – BMI – often fall short of providing a realistic estimate of adiposity and, therefore, of ongoing pathologies at the systemic, tissue and cellular level. In the quest for identifying new more robust diagnostic markers, whole-organ analysis of chemical elements is a promising approach for identifying candidate proxies of obesity status in the system.MethodsTotal Reflection X-ray fluorescence (TXRF) coupled with biochemical assays, chemometrics and statistical validation was used as a new integrated pipeline for marker identification in external ear samples of obese animals. The specimens were taken from obese animals fed a high calorie diet as well as from lean intact animals fed a standard diet.ResultsThe most significant differences in the content of K, Fe, Br, and Rb between the studied groups of the animals were identified. However, with the methodology applied Rb was found the most robust biochemical discriminator of early-stage obesity effects, as validated by the logistic regression model. We observed no relationship between the levels of the elements consumed by the animals and their apparent content in the earlobe tissue samples.ConclusionsOur preliminary study confirms that obesity alters tissue trace metal metabolism and shows the proposed new approach as an accurate and reliable methodology for detecting tissue elemental obesity-related alterations.General significanceThis result can be of practical significance for designing new point-of-care systems for obesity screening tests, taking advantage of direct/indirect Rb measurements. 相似文献
10.
Although several plants belonging to the Bromeliaceae family have been used as heavy metal accumulators in biomonitoring studies, their accumulation ability has not been investigated. The present study obtained the accumulation rates of Ni2+, Cu2+, Pb2+ and Zn2+ in leaves of Tillandsia capillaris and revealed their effects on lipid peroxidation by measuring the Malondialdehyde content (MDA). Leaves of T. capillaris were exposed to different metallic solutions of Cu2+, Ni2+, Pb2+ and Zn2+ cations. After this exposure period, the accumulation of these ions was measured by Total Reflection X-Ray Fluorescence (TXRF) analysis with Synchrotron Radiation, and the MDA content was calculated. Data sets were evaluated by a one-way analysis of variance (ANOVA) and a fitted regression hyperbola model. The results showed significant differences in the accumulation efficiencies of the cations under study. In addition, the enrichment factor (EF) estimated for these cations was higher for Ni2+, suggesting a greater affinity of the plant with this element. Over time, all the metals under study caused significant increases in the MDA content, indicating their toxicity effects even in the most diluted solutions used in this study. 相似文献
11.
Radoslavov G Jordanova R Teofanova D Georgieva K Hristov P Salomone-Stagni M Liebau E Bankov I 《PloS one》2010,5(10):e13343
Background
Trichinella spiralis is an unusual parasitic intracellular nematode causing dedifferentiation of the host myofiber. Trichinella proteomic analyses have identified proteins that act at the interface between the parasite and the host and are probably important for the infection and pathogenesis. Many parasitic proteins, including a number of metalloproteins are unique for the nematodes and trichinellids and therefore present good targets for future therapeutic developments. Furthermore, detailed information on such proteins and their function in the nematode organism would provide better understanding of the parasite - host interactions.Methodology/Principal Findings
In this study we report the identification, biochemical characterization and localization of a novel poly-cysteine and histidine-tailed metalloprotein (Ts-PCHTP). The native Ts-PCHTP was purified from T. spiralis muscle larvae that were isolated from infected rats as a model system. The sequence analysis showed no homology with other proteins. Two unique poly-cysteine domains were found in the amino acid sequence of Ts-PCHTP. This protein is also the first reported natural histidine tailed protein. It was suggested that Ts-PCHTP has metal binding properties. Total Reflection X-ray Fluorescence (TXRF) assay revealed that it binds significant concentrations of iron, nickel and zinc at protein:metal ratio of about 1∶2. Immunohistochemical analysis showed that the Ts-PCHTP is localized in the cuticle and in all tissues of the larvae, but that it is not excreted outside the parasite.Conclusions/Significance
Our data suggest that Ts-PCHTP is the first described member of a novel nematode poly-cysteine protein family and its function could be metal storage and/or transport. Since this protein family is unique for parasites from Superfamily Trichinelloidea its potential applications in diagnostics and treatment could be exploited in future. 相似文献12.
Stephen R. Cohen 《Journal of neurochemistry》1980,35(4):1008-1012
Concentrative influx of γ-aminobutyric acid (GABA) and α-aminoisobutyric acid (AIB) into incubated mouse cerebrum slices is decreased when pyruvate is substituted for glucose. Influx of GABA from pyruvate medium is not increased by presence of glucose, 2-deoxy-d -glucose (2-DOG), or 3-O-methyl-d -glucose (3-O-MeG). Influx of AIB is restored to the rate from glucose medium if 2-DOG is present initially, but is not restored if 2-DOG is added with AIB. Influx is not restored if 3-O-MeG is present initially, but is restored if 3-O-MeG is added with AIB. Influx is restored if glucose is present initially or is added with AIB. 相似文献
13.
The effect of inosine on the development of competence is dependent upon the time at which it is added to the competence medium. Competence is inhibited if inosine is added within 15 min after the development begins, but is stimulated if the addition is made at later times. Protein synthesis is stimulated by the addition of inosine, but the effect is quantitatively similar regardless of the time at which inosine is added. 相似文献
14.
268例难治性下呼吸道感染的细菌学分析 总被引:5,自引:0,他引:5
通过本组268 例难治性呼吸道感染病人标本培养结果分析,阳性246 例占91.8 % ,有154 例检出厌氧菌,占57 % ,104 例检出需氧菌,占39 % ,混合感染133 例,占50 % 。试验结果证实,厌氧菌感染在难治性下呼吸道感染病例中占了很大比例,这一结果为难治性下呼吸道感染的治疗提供了有价值的参考数据。 相似文献
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Andrew Wojcicki 《Inorganica chimica acta》1985,100(1):125-133
Studies are reported on the chemical reduction of the homobinuclear bis(μ-phosphido) metal complexes (R = Ph or Me), and (M = Mo or W). Two reduction pathways have been observed which result in different two-electron transformations: (1) with Na or LiAlH4, electron transfer to yield the corresponding symmetric dianions of the type LnM(μ-PR2)2MLn2? without metalmetal bond and (2) with M′BR′3H(M′ = Li, Na, or K; R′ = Et or sec-Bu), hydride transfer to give monoanionic complexes of the type or (M = Fe, Mo, or W; L = CO or NO; R = Ph or Me). The monoanionic complexes can be deprotonated with n-BuLi at ?78 °C to the corresponding unsymmetric dianions (M = Fe; L = CO or NO; R = Ph) or symmetric dianions LnM(μ-PR2)2MLn2? (M = Mo or W; L = CO; R = Ph). The unsymmetric dianions isomerize on slight warming to the symmetric dianions, which undergo protonation by CF3COOH to yield the aforementioned monoanions. Reactions of several members of these three classes of binuclear anions with CF3COOH, alkylating reagents, 1,1-diiodohydrocarbons and metal diiodo complexes have resulted in the synthesis of new binuclear and trinuclear compounds. Examples include , (R = Me, Et, n-Pr, or i-Pr), (M = Mo or W; R = Me or Ph), , , , and Fe2Co(η5-C5H5)(CO)(NO)4(μ-PPh2)2. Synthetic and mechanistic studies on these reactions are presented. 相似文献
18.
Naohiro Nishikawa Yoshitake Sakae Takuya Gouda Yuichiro Tsujimura Yuko Okamoto 《Biophysical journal》2019,116(5):781-790
A peptide -, which is a fragment from residue 21 to residue 31 of -microgloblin, is experimentally known to self-assemble and form amyloid fibrils. In order to understand the mechanism of amyloid fibril formations, we applied the replica-exchange molecular dynamics method to the system consisting of three fragments of -. From the analyses on the temperature dependence, we found that there is a clear phase transition temperature in which the peptides aggregate with each other. Moreover, we found by the free energy analyses that there are two major stable states: One of them is like amyloid fibrils and the other is amorphous aggregates. 相似文献
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Wang W 《Mathematical biosciences》2006,201(1-2):58-71
An epidemic model with a limited resource for treatment is proposed to understand the effect of the capacity for treatment. It is assumed that treatment rate is proportional to the number of infectives below the capacity and is a constant when the number of infectives is greater than the capacity. It is found that a backward bifurcation occurs if the capacity is small. It is also found that there exist bistable endemic equilibria if the capacity is low. 相似文献