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Many carbonatites are associated both spatially and temporally with large igneous provinces (LIPs), and considered to originate from a mantle plume source lacking any contribution from recycled crustal materials. Here, we report an occurrence of carbonatite enriched in rare-earth elements (REE) and associated with the Tarim LIP in northwestern China. The Tarim LIP comprises intrusive and volcanic products of mantle plume activity spanning from ~ 300 to 280 Ma. The carbonatites at Wajilitage in the northwestern part of Tarim are dominated by calcite and dolomite varieties, and contain abundant REE minerals (principally, monazite and REE-fluorcarbonates). Th–Pb age determination of monazite yielded an emplacement age of 266 ± 5.3 Ma, i.e. appreciably younger than the eruption age of flood basalts at ~ 290 Ma. The carbonatites show low initial 87Sr/86Sr (0.7037–0.7041) and high eNd(t) (1.2–4) values, which depart from the isotopic characteristics of plume-derived basalts and high-Mg picrites from the same area. This indicates that the Wajilitage carbonatites derived from a mantle source isotopically distinct from the one responsible for the voluminous (ultra)mafic volcanism at Tarim. The carbonatites show δ26MgDSM3 values (− 0.99 to − 0.65‰) that are significantly lower than those in typical mantle-derived rocks and rift carbonatites, but close to marine sediments and orogenic carbonatites. We propose that the carbonatites in the Tarim LIP formed by decompressional melting of recycled sediments mixed with the ambient mantle peridotite. The enriched components in the Tarim plume could be accounted for by the presence of recycled sedimentary components in the subcontinental mantle.

Nowadays increasing attention has been focused on polyphenolic compounds as the main representants of antioxidants in horticultural crops including fruits. The edible honeysuckle has an unique position among lesser known fruits due to its high level of antioxidants. In the present study we determined polyphenolic profile and antioxidant capacity of four Russian cultivars of edible honeysuckle including ‘Gerda 25’, ‘Amfora’, ‘Morena’, ‘Lipnicka’, which found together in a single location in Mendel University in Brno, The Czech Republic. Polyphenolic compounds were detected by high performance liquid chromatography coupled with electrochemical detector (HPLC-ED). The antioxidant capacity was measured by DPPH test. According to the results there were differences among cultivars in terms of polyphenolic content and antioxidant activity and Lonicera kamtschatica ‘Gerda 25’ were found to be possessed the highest content of phenolic compounds corresponding to the highest value of antioxidant activity.

Most studies of compositional heterogeneities in the mantle, related to recycling of crustal sediments or delaminated subcontinental lithosphere, come from oceanic setting basalts. In this work, we present direct geochronological and geochemical evidence for the incorporation of recycled crustal materials in collision-related carbonatites of the South Qinling orogenic belt (SQ), which merges with the Lesser Qinling orogen (LQ) to separate the South and North China Blocks. The SQ carbonatites occur mainly as stock associated with syenites. The data presented here show that zircon from the syenites yields an age of 766 ± 25 Ma, which differs significantly from the age of primary monazite from the carbonatites (233.6 ± 1.7 Ma). The syenites contain lower initial 87Sr/86Sr and higher eNd values. This indicates that the carbonatites do not have genetically related with the silicate rocks, and were directly derived from a primary carbonate magma generated in the mantle. The carbonatites show a Sr–Nd isotopic signature similar to that of the chondritic uniform reservoir (CHUR), and parallel Sm–Nd model ages (TCHUR) of 190–300 Ma. However, the rocks have extremely variable Pb isotopic values straddling between the HIMU and EM1 mantle end-members. Most carbon and oxygen isotopic compositions of the SQ carbonatites plot outside the field for primary igneous carbonates. Their δ13C shows higher value than a ‘normal’ mantle, which implies an incorporation of recycled inorganic carbon. The carbonatites were emplaced close to the Mianlue suture, and followed the closure of the Mianlue ocean and Triassic collision of the South and North China Blocks. However, direct melting of the subducted Mianlue oceanic crust characterized by high eNd and low (EM1-like) 206Pb/204Pb values cannot explain the CHUR-like Nd signature and the Pb isotopic trend toward HIMU in the SQ carbonatites. We conclude that their parental magma was derived from a source incorporating the Mianlue oceanic crust mixed with an asthenospheric (or deeper) material characterized by high Pb and low Nd isotopic values. This material represents a deep-seated Proterozoic carbonate component recycled via mantle convection or localized upwelling. Notably, this model cannot explain the isotopic compositions of the Late Triassic (209–221 Ma) carbonatites in the LQ, characterized by a mantle-derived δ13C, but EM1-like Sr–Nd–Pb isotopic compositions. This signature is best explained in terms of delamination of the lower continental crust thickened during the collision of the South and North China Blocks, and partial incorporation of the delaminated material into the LQ mantle source. Modeling of the measured Sr–Nd–Pb isotopic variations suggests that the source of the LQ carbonatites could be produced by mixing of 80–85% of mantle material and 15–20% of delaminated lower continental crust. The emplacement of the SQ and LQ carbonatites marked a gradual transition from a compressional tectonic regime, brought about by the collision of the South and North China Blocks to intra-orogenic extension in the waning stages of the Triassic orogeny.

The nanotechnological concept is based on size-dependent properties of particles in the 1–100 nm range. Nevertheless, the connection between their size and effect is still not clear. Thus, we focused on reductive colloidal synthesis, characterization and biological testing of Pt nanoparticles (PtNPs) capped with biocompatible polymer polyvinylpyrrolidone (PVP). Synthesized PtNPs were of 3 different primary sizes (approx. ∼10; ∼14 and > 20 nm) and demonstrated exceptional haemocompatibility. In vitro treatment of three different types of malignant cells (prostate – LNCaP, breast – MDA-MB-231 and neuroblastoma – GI-ME-N) revealed that even marginal differences in PtNPs diameter resulted in changes in their cytotoxicity. The highest cytotoxicity was observed using the smallest PtNPs-10, where 24IC 50 was lower (3.1–6.2 μg/mL) than for cisplatin (8.1–19.8 μg/mL). In contrast to MDA-MB-231 and LNCaP cells, in GI-ME-N cells PtNPs caused noticeable changes in their cellular structure without influencing their viability. Post-exposure analyses revealed that PtNPs-29 and PtNPs-40 were capable of forming considerably higher amount of reactive oxygen species with consequent stimulation of expression of metallothionein (MT1/2 and MT3), at both mRNA and protein level. Overall, our pilot study demonstrates that in the nanoscaled world even the smallest differences can have crucial biological effect.

Interactions of silver phosphate nanoparticles (SPNPs) and selenium nanoparticles (SeNPs) with Staphylococcus aureus cultures have been studied at the cellular, molecular and protein level. Significant antibacterial effects of both SPNPs and SeNPs on S. aureus were observed. At a concentration of 300 μM, SPNPs caused 37.5% inhibition of bacterial growth and SeNPs totally inhibited bacterial growth. As these effects might have been performed due to the interactions of nanoparticles with DNA and proteins, the interaction of SPNPs or SeNPs with the amplified zntR gene was studied. The presence of nanoparticles decreased the melting temperatures of the nanoparticle complexes with the zntR gene by 23% for SeNPs and by 12% for SPNPs in comparison with the control value. The concentration of bacterial metallothionein was 87% lower in bacteria after application of SPNPs (6.3 μg mg(-1) protein) but was increased by 29% after addition of SeNPs (63 μg mg(-1) protein) compared with the S. aureus control (49 μg mg(-1) protein). Significant antimicrobial effects of the nanoparticles on bacterial growth and DNA integrity provide a promising approach to reducing the risk of bacterial infections that cannot be controlled by the usual antibiotic treatments.

Nucleic acids belong to the most important molecules and therefore the understanding of their properties, function and behavior is crucial. Even though a range of analytical and biochemical methods have been developed for this purpose, one common step is essential for all of them – isolation of the nucleic acid from the from complex sample matrix. The use of magnetic particles for the separation of nucleic acids has many advantages over other isolation methods. In this study, an isolation procedure for extraction of DNA was optimized. Each step of the isolation process including washing, immobilization and elution was optimized and therefore the efficiency was increased from 1.7% to 28.7% and the total time was shortened from 75 to 30 min comparing to the previously described method. Quantification of the particular parameter influence was performed by square-wave voltammetry using hanging drop mercury electrode. Further, we compared the optimized method with standard chloroform extraction and applied on isolation of DNA from Staphylococcus aureus and Escherichia coli.

Carcinoma of prostate (CaP) is the second most frequent malignant tumor occurring in men in Europe. Currently there is discussion on a wide range of potential CaP markers. One of them-nonprotein amino acid sarcosine, also known as N-methylglycine was chosen as a challenge for the development of microfluidic system with isolation by modified paramagnetic microparticles. Therefore, the aim of this study was to design a low-cost, simple, and rapid microfluidic system based on sarcosine isolation with modified paramagnetic microparticles and subsequent analysis on the ion exchange LC. We modified Dowex microparticles with Fe2O3 nanoparticles. Our paramagnetic microparticles were able to establish the binding with sarcosine. Moreover, we designed microfluidic device for sarcosine determination. Analysis of samples was carried out with LOD of 1 uM of a sarcosine that is sufficient because it is similar to concentrations of a sarcosine observed in the CaP patients.

Polymers are currently widely used to replace a variety of natural materials with respect to their favourable physical and chemical properties, and due to their economic advantage. One of the most important branches of application of polymers is the production of different products for medical use. In this case, it is necessary to face a significant disadvantage of polymer products due to possible and very common colonization of the surface by various microorganisms that can pose a potential danger to the patient. One of the possible solutions is to prepare polymer with antibacterial/antimicrobial properties that is resistant to bacterial colonization. The aim of this study was to contribute to the development of antimicrobial polymeric material ideal for covering vascular implants with subsequent use in transplant surgery. Therefore, the complexes of polymeric substances (hyaluronic acid and chitosan) with silver nitrate or silver phosphate nanoparticles were created, and their effects on gram-positive bacterial culture of Staphylococcus aureus were monitored. Stages of formation of complexes of silver nitrate and silver phosphate nanoparticles with polymeric compounds were characterized using electrochemical and spectrophotometric methods. Furthermore, the antimicrobial activity of complexes was determined using the methods of determination of growth curves and zones of inhibition. The results of this study revealed that the complex of chitosan, with silver phosphate nanoparticles, was the most suitable in order to have an antibacterial effect on bacterial culture of Staphylococcus aureus. Formation of this complex was under way at low concentrations of chitosan. The results of electrochemical determination corresponded with the results of spectrophotometric methods and verified good interaction and formation of the complex. The complex has an outstanding antibacterial effect and this effect was of several orders higher compared to other investigated complexes.

Volcanic-plutonic alkaline complexes from Lugiin Gol, Mushgai Khudag and Bayan Khoshuu, southern Mongolia (244, 139 and 131 Ma, respectively) occur within grabens in E-W lineaments. They are represented by syenitic rock-types (silica undersaturated to slightly silica oversaturated) potassic rocks and are associated to stockworks of carbonatitic veins, dykes and so on. Geochemical characteristics and isotope systematics point to a veined mantle source particularly enriched in LILE and LREE. The carbonatitic veins show high contents of Ba, Sr, Th and REE and are suitable as potential ore deposits.

Pathogenic bacteria have become a serious socio-economic concern. Immunomagnetic separation-based methods create new possibilities for rapidly recognizing many of these pathogens. The aim of this study was to use superparamagnetic particles-based fully automated instrumentation to isolate pathogen Staphylococcus aureus and its Zn(II) containing proteins (Zn-proteins). The isolated bacteria were immediately purified and disintegrated prior to immunoextraction of Zn-proteins by superparamagnetic beads modified with chicken anti-Zn(II) antibody. S. aureus culture was treated with ZnCl(2). Optimal pathogen isolation and subsequent disintegration assay steps were carried out with minimal handling. (i) Optimization of bacteria capturing: Superparamagnetic microparticles composed of human IgG were used as the binding surface for acquiring live S. aureus. The effect of antibodies concentration, ionic strength, and incubation time was concurrently investigated. (ii) Optimization of zinc proteins isolation: pure and intact bacteria isolated by the optimized method were sonicated. The extracts obtained were subsequently analyzed using superparamagnetic particles modified with chicken antibody against zinc(II) ions. (iii) Moreover, various types of bacterial zinc(II) proteins precipitations from particle-surface interactions were tested and associated protein profiles were identified using SDS-PAGE. Use of a robotic pipetting system sped up sample preparation to less than 4 h. Cell lysis and Zn-protein extractions were obtained from a minimum of 100 cells with sufficient yield for SDS-PAGE (tens ng of proteins). Zn(II) content and cell count in the extracts increased exponentially. Furthermore, Zn(II) and proteins balances were determined in cell lysate, extract, and retentate.

Carbonatites, usually occurring within intra-continental rift-related settings, have strong light rare earth element (LREE) enrichment; they rarely contain economic heavy REE (HREE). Here, we report the identification of Late Triassic HREE-Mo-rich carbonatites in the northernmost Qinling orogen. The rocks contain abundant primary HREE minerals and molybdenite. Calcite-hosted fluid inclusions, inferred to represent a magmatic-derived aqueous fluid phase, contain significant concentrations of Mo (~17 ppm), reinforcing the inference that these carbonatitic magmas had high Mo concentrations. By contrast, Late Triassic carbonatites in southernmost Qinling have economic LREE concentrations, but are depleted in HREE and Mo. Both of these carbonatite types have low δ26Mg values (−1.89 to −1.07‰), similar to sedimentary carbonates, suggesting a recycled sediment contribution for REE enrichment in their mantle sources. We propose that the carbonatites in the Qinling orogen were formed, at least in part, by the melting of a subducted carbonate-bearing slab, and that 10 Ma younger carbonatite magmas in the northernmost Qinling metasomatized the thickened eclogitic lower crust to produce high levels of HREE and Mo.

Panxi region in west Sichuan province is one of the most economically significant REE mineralization belts in China, and includes the large Maoniuping and Daluxiang deposits and the minor Lizhuang deposit. The REE mineralization in these deposits is spatially and temporally associated with carbonatite–syenite complexes. Large proportional fluorites and REE minerals occurring as veins intrude Cretaceous granite and Oligocene syenite in Maoniuping, and Oligocene syenite and carbonatite in Lizhuang, and Miocene syenite in Daluxiang. Fluorite is also one of main gangue minerals in the world-class Bayan Obo REE deposit. We present a comparison of the trace element and isotopic compositions of fluorites from four REE deposits in the Panxi region and Bayan Obo. The fluorites from Maoniuping and Daluxiang are characterized by variable REE patterns, with either LREE enrichment or LREE depletion relative to MREE. Typically they have a larger range in La/Ho compared to Y/Ho ratios, and pronounced positive Y anomaly relative to chondrite-normalized REE patterns. Their REE distribution patterns are controlled by fluoride-complexes and the loss of separate LREE-rich minerals. Different Y/Ho (ca. 73 vs. 108) and initial Sr isotopic (ca. 0.7061 vs. 0.7077) ratios are observed between the fluorites from Maoniuping and Daluxiang, reflecting their different source compositions. This contrasts with the fluorites from Maoniuping and Lizhuang, which have similar initial Sr isotopes, and appear to be cogenetic. However, the Lizhuang fluorite shows a consistent depletion of LREE relative to MREE, as well as lower Y/Ho ratios and higher HREE content than that in Maoniuping. In this respect the Lizhuang fluorite may have precipitated from a late-stage fluid following abundant fluorite and REE mineral deposition in Maoniuping. Carbonate, more than fluoride complexing, appears to have a stronger control on REE fractionation in the Lizhuang fluorites. The fluorites from three deposits in Panxi region show uniform initial Sr and Nd isotopic compositions similar to their associated carbonatites, but differ from ore-veins found intruding wall rocks, e.g. granite in Maoniuping and syenite in Daluxiang. This is not consistent with a model for fluorite formation involving interaction of F-rich, carbonatite-exsoloved fluid with wall rocks. Instead, the fluorite in Panxi region may precipitate from a residual carbonthermal fluid, which was dominated by Ca, CO2 but also contained F, H2O and REE, and derived from the fractioned carbonatitic magma. Fluorite deposition produced a sharp drop in the activity of F−, which destabilized the REE fluoride complexes and caused deposition of REE minerals. In Bayan Obo, the fluorite typically has higher La/Ho than that in Panxi region and is characterized by a consistent LREE enrichment relative to MREE and negligible to positive Y anomalies. This is consistent with the compositional change of the hydrothermal fluids, which were infiltrated by external F-, LREE-rich fluids. The 87Sr/86Sr of Bayan Obo fluorite is relatively low radiogenic, and has a large range (0.7038–0.7065): similar characteristics to the carbonatite dykes found near the ore bodies. This supports a model for fluorite and REE mineral genesis involving the interaction of a carbonatite-derived fluid and the ore-hosted dolomitic marble.

A swarm of Late Triassic (220 Ma) carbonatite dykes is emplaced into the deformed southern margin of the North China block (NCB) at Lesser Qinling, discontinuously extending for about 10 km. The carbonatites are volumetrically minor, and their formation is related to collision between the South China block (SCB) and Qinling orogen, which led to the amalgamation of the NCB and SCB. The carbonatites are intruded into different Archean and Mesoproterozoic wall-rocks, but are characterized by remarkably similar isotopic compositions [(87Sr/86Sr)i = 0.7048–0.7057; ?Nd = ? 4.3 to ? 10.1; 207Pb/206Pb = 0.878–0.889 and 208Pb/206Pb = 2.136–2.160], which approach, and trend toward slightly less radiogenic Sr and Nd values than, the enriched mantle component EM1. Proterozoic oceanic crust recycled through deep mantle is interpreted to be the principal source of carbon for the Lesser Qinling carbonatites. In comparison with most other young carbonatites (< 200 Ma) emplaced in a rift setting, the Lesser Qinling suite contains appreciably lower ?Nd and higher 207Pb/206Pb and 208Pb/206Pb values, which suggest the presence of an isotopically distinct additional component in its mantle source. The Pb isotopic signature of these carbonatites is significantly distinct from that of the Precambrian rocks in the North China block, but is similar to that of basement rocks in the South Qinling. On the basis of the available isotopic, geophysical and tectonic constraints, we suggest that the southern margin of the North China block was underthrust by crustal material derived from the South Qinling during their collision. The underthrusting contributed to thickening of the lower crust beneath the North China block and its conversion to dense eclogite. This process culminated in brittle delamination of the eclogitized material into the mantle and its metasomatic reworking by carbonate-rich melts derived from the EM1-type recycled Proterozoic crust. Carbonate metasomatism could produce an enriched sub-continental lithospheric source capable of yielding a variety of magma types.

The western part of the Khan Bogd complex comprises (in order of emplacement): microcline-phyric granite, peralkaline aegirine-arfvedsonite granite (main intrusive phase) and aplite-pegmatite veins confined predominantly to the apical parts of the intrusion. These rocks are interpreted to represent products of extreme fractional crystallization what involved an increase in index of peralkalinity (from 1.0 in the porphyritic granite to 1.3 in the main phase to 2.5 in the pegmatite) and whole-rock Zr content (864 to 1130 to 16900 ppm). The hydrothermal stage involved replacement of the primary elpidite by late-stage Ca-rich elpidite or armstrongite, and then precipitation of minor gittinsite and abundant zircon. With the exception of zircon, all secondary zirconosilicates exhibit relative enrichment in light REE.

Carbonatites are known to contain the highest concentrations of rare-earth elements (REE) among all igneous rocks. The REE distribution of carbonatites is commonly believed to be controlled by that of the rock-forming Ca minerals (i.e., calcite, dolomite, and ankerite) and apatite because of their high modal content and tolerance for the substitution of Ca by light REE (LREE). Contrary to this conjecture, calcite from the Miaoya carbonatite (China), analyzed in situ by laser-ablation inductively-coupled-plasma mass-spectrometry, is characterized by low REE contents (100–260 ppm) and relatively flat chondrite-normalized REE distribution patterns [average (La/Yb)CN = 1.6]. The carbonatite contains abundant REE-rich minerals, including monazite and fluorapatite, both precipitated earlier than the REE-poor calcite, and REE-fluorocarbonates that postdated the calcite. Hydrothermal REE-bearing fluorite and barite veins are not observed at Miaoya. The textural and analytical evidence indicates that the initially high concentrations of REE and P in the carbonatitic magma facilitated early precipitation of REE-rich phosphates. Subsequent crystallization of REE-poor calcite led to enrichment of the residual liquid in REE, particularly LREE. This implies that REE are generally incompatible with respect to calcite and the calcite/melt partition coefficients for heavy REE (HREE) are significantly greater than those for LREE. Precipitation of REE-fluorocarbonates late in the evolutionary history resulted in depletion of the residual liquid in LREE, as manifested by the development of HREE-enriched late-stage calcite [(La/Yb)CN ≈ 0.7] in syenites associated with the carbonatite. The observed variations of REE distribution between calcite and whole rocks are interpreted to arise from multistage fractional crystallization (phosphates ⇒ calcite ⇒ REE-fluorocarbonates) from an initially REE-rich carbonatitic liquid.

The Qinling molybdenum belt is a prominent metallogenic structure in central China hosting several significant porphyry- and porphyry–skarn-type deposits. The Huanglongpu Mo deposit in the north-western part of the belt is unique in that it is associated with carbonatite dykes, rather than felsic magmatism. The carbonatites are composed largely of Sr–Mn-rich calcite and characterized by high concentrations of Sr and rare-earth elements (REE), and stable-isotope values indicative of a mantle source (δ13CPDB = − 6.7 ± 0.2‰ and δ18OSMOW = 8.2 ± 1.0‰). Molybdenite is associated with galena and REE minerals (parisite, bastnasite and monazite). Both molybdenite and galena are characterized by high Re contents (up to 0.4 and 0.2 wt.%, respectively) and Re/(Mo, Pb) ratios approaching the primitive-mantle values. In contrast to the rock-forming calcite, the REE minerals are enriched in light REE, whose relative proportion increases from parisite-(Ce) [average (La/Nd)n = 2.1] to bastnasite-(Ce) and monazite-(Ce) [average (La/Nd)n = 3.1, 4.6, respectively]. The whole-rock compositions are characterized by some of the highest Mo and heavy REE abundances reported for carbonatites to date: up to 1010 ppm Mo, 1130 ppm Y + Gd…Lu and (La/Yb)n = 1.2–2.7. The unusual trace-element geochemistry of the Huanglongpu rocks may ultimately reflect the composition of their mantle source, but their enrichment in Mo + Re was undoubtedly enhanced through preferential partitioning of these elements into a light REE–Pb–S-rich fluid derived from the carbonatitic magma modified by calcite fractionation. The present work shows that Mo can be retained, transported and deposited by carbonatitic fluids capable of generating economic Mo deposits.

Although cancer is one of the most dangerous and the second most lethal disease in the world, current therapy including surgery, chemotherapy, radiotherapy, etc., is highly insufficient not in the view of therapy success rate or the amount of side effects. Accordingly, procedures with better outcomes are highly desirable. Iron oxide nanoparticles (IONPs) present an innovative tool-ideal for innovation and implementation into practice. This review is focused on summarizing some well-known facts about pharmacokinetics, toxicity, and the types of IONPs, and furthermore, provides a survey of their use in cancer diagnosis and therapy.

Although carbonatites potentially contain a larger concentration of rare earth elements (REEs) than any rock type, the origin of the REE mineralization in the world's largest Bayan Obo carbonatite-related deposit is still disputed. In order to clarify the mechanism of REE mineralization, carbonatite samples from three large REE deposits in China, Daluxiang, Maoniuping and Bayan Obo were compared. The REE minerals in Daluxiang and Maoniuping carbonatites show constant light REE (LREE) enrichment (chondrite normalized (La/Nd)N ratios > 1), whereas those in Bayan Obo H8 dolomite marbles show variable (La/Nd)N ratios. The REE abundances and patterns of the REE minerals in Maoniuping carbonatites are similar to those in the barite, calcite and thread vein-hosted ores. The calcites in Daluxiang and Maoniuping carbonatites are characterized by enrichments of Pb, Sr and REEs, which is consistent with an igneous origin. They have similar REE contents and patterns to the corresponding bulk rocks, suggesting that these carbonatites are calcite-rich cumulates. During crystallization and accumulation of calcites, the REEs become enriched in carbonatite-expelled fluids because of the very low partition coefficients for these elements between carbonate minerals and melt. These fluids interact with the country rocks to produce fluorite-rich REE mineralization. The fluorites in Daluxiang and Maoniuping deposits are characterized by high Sr contents and REE patterns that vary from LREE enriched to LREE depleted. The former has relatively higher Sr and lower heavy REE (HREE) concentrations than those in Maoniuping, which is consistent with the differences found in carbonatites and calcites from the two locations. In addition, the high MnO, Sr and REE contents of dolomites in REE–Nb–Fe host H8 dolomite marble in Bayan Obo support the hypothesis that the rock is of igneous origin. In situ analyses show compositional differences between coarse- and fine-grained dolomites. The latter has higher Nb and LREEs, and lower FeO and 207Pb/206Pb and 208Pb/206Pb ratios. Our data confirm previous interpretations of the complex, multistage nature of REE and Nb mineralization at Bayan Obo, in which the ore is produced by reaction between carbonatite-derived fluids and the ore host dolomite marbles. This hypothesis is supported by the age of adjacent carbonatite dykes, which have the same age range as ore formation. A similar REE mineralization model is proposed for the Daluxiang and Maoniuping carbonatite deposits.

V této práci jsme se zaměřili na rozdíly mezi bakteriálních kultur E. coli, získaných ze stěrů infekčních ran pacientů ve srovnání s laboratorním E. coli. Navíc blokování proteinu odpovědné za syntézu glutathion (-glutamyl-cystein synthasy GCL) za použití 10 mM buthionin sulfoximin byla zkoumána. Každý E. coli ukázala výrazné rozdíly v rezistenci vůči antibiotikům. Podle odhodlaný odolné, E. coli byly rozděleny do experimentálních skupin na základě statistického vyhodnocení jejich vlastností jako odolnější a citlivější. Tyto skupiny byly také použity pro nalezení rozdíly mezi nimi v závislosti na glutathion dráhy o rezistenci na antibiotika. Citlivější E. coli vykazovaly stejné kinetiky glutathionu syntézy zatímco blokuje GCL (km 0,1 um), ve srovnání s non-blokování. Kromě toho, nejčastější mutace v genech glutathion syntetázy, glutathion peroxidázy a glutathionreduktasy byly pozorovány v této skupině ve srovnání s laboratorní E. coli. Skupina "odolnější" E. coli vykazovaly rozdíly v km mezi 0,3 a 0,8 uM. Počet mutací ve srovnání s E. coli laboratoře byla podstatně nižší v porovnání s jinou skupinou. In this work, we focused on the differences between bacterial cultures of E. coli obtained from swabs of infectious wounds of patients compared to laboratory E. coli. In addition, blocking of the protein responsible for the synthesis of glutathione (-glutamylcysteine synthase—GCL) using 10 mM buthionine sulfoximine was investigated. Each E. coli showed significant differences in resistance to antibiotics. According to the etermined resistance, E. coli were divided into experimental groups based on a statistical evaluation of their properties as more resistant and more sensitive. These groups were also used for finding the differences in a dependence of the glutathione pathway on resistance to antibiotics. More sensitive E. coli showed the same kinetics of glutathione synthesis while blocking GCL (Km 0.1 M), as compared to non-blocking. In addition, the most frequent mutations in genes of glutathione synthetase, glutathione peroxidase and glutathione reductase were observed in this group compared to laboratory E.coli. The group of “more resistant” E. coli exhibited differences in Km between 0.3 and 0.8 M. The number of mutations compared to the laboratory E. coli was substantially lower compared to the other group.

In this study a device for automatic electrochemical analysis was designed. A three electrodes detection system was attached to a positioning device, which enabled us to move the electrode system from one well to another of a microtitre plate. Disposable carbon tip electrodes were used for Cd(II), Cu(II) and Pb(II) ion quantification, while Zn(II) did not give signal in this electrode configuration. In order to detect all mentioned heavy metals simultaneously, thin-film mercury electrodes (TFME) were fabricated by electrodeposition of mercury on the surface of carbon tips. In comparison with bare electrodes the TMFEs had lower detection limits and better sensitivity. In addition to pure aqueous heavy metal solutions, the assay was also performed on mineralized rock samples, artificial blood plasma samples and samples of chicken embryo organs treated with cadmium. An artificial neural network was created to evaluate the concentrations of the mentioned heavy metals correctly in mixture samples and an excellent fit was observed (R2 = 0.9933). V této studii byla navržena automatická elektrochemická analýza. Detekční systém složený ze tří elektrod byl připojen k polohovacímu zařízení, které nám umožnilo manipulaci s elektrodou z jedné jamky na druhou mikrotitrační destičky. Jednorázový uhlíkový tip elektrody byl použit pro kvantifikaci Cd (II), Cu (II) a Pb (II) iontů, zatímco Zn (II) neměl signál v této konfiguraci elektrody. Aby bylo možné odhalit všechny uvedené těžké kovy současně pomocí tenkovrstvé rtuťové elektrody (TFME), byly vyrobeny podle elektrodepozicí rtuti na povrchu hrotů uhlíku. Ve srovnání s holýma elektrodami se TMFEs měli nižší detekční limity a lepší citlivost. Kromě čistého vodného roztoku těžkých kovů ....

The microwave-assisted synthesis of goethite nanoparticles has been studied. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential thermal analysis (DTA) and Brunauer-Emmett-Teller (BET) method. Goethite rod-like nanoparticles have been successfully synthesized in 10 min of microwave treating at 100 degrees C. Particle size is in the range from 30 to 60 nm in width and from 200 to 350 nm in length. BET analysis indicated that the surface area of the product is 158.31 m(2)g(-1). The feasibility of Cr(VI) removal fromaqueous solution depends on the pH of the solution and contact time. The maximum adsorptionis reached at pH 4.0 and 540 min of contact time. The adsorption kinetics was analyzedby the pseudo-first-and second-order models and the results reveal that the adsorption process obeys the pseudo-second-order model. The adsorption data were fitted well with the Langmuir adsorption isotherm.

There is an arising and concerning issue in the field of bacterial resistance, which is confirmed by the number of deaths associated with drug-resistant bacterial infections. The aim of this study was to compare the effects of antibiotics on Staphylococcus aureus non-resistant strain and strains resistant to cadmium or lead ions. Metal resistant strains were created by the gradual addition of 2 mM solution of metal ions (cadmium or lead) to the S. aureus culture. An increasing antimicrobial effect of ampicillin, streptomycin, penicillin and tetracycline (0, 10, 25, 50, 75, 150, 225 and 300 mu M) on the resistant strains was observed using a method of growth curves. A significant growth inhibition (compared to control) of cadmium resistant cells was observed in the presence of all the four different antibiotics. On the other hand, the addition of streptomycin and ampicillin did not inhibit the growth of lead resistant strain. Other antibiotics were still toxic to the bacterial cells. Significant differences in the morphology of cell walls were indicated by changes in the cell shape. Our data show that the presence of metal ions in the urban environment may contribute to the development of bacterial strain resistance to other substances including antibiotics, which would have an impact on public health. K dispozici je vznikající a pokud jde o problém v oblasti bakteriální rezistence, což je potvrzeno počtu úmrtí souvisejících s drogami odolné proti bakteriálním infekcím. Cílem této studie bylo porovnat účinky antibiotik na kmen bez rezistentní Staphylococcus aureus a kmenů rezistentních k kadmia nebo olova ionty. Kmeny odolného kovu byly vytvořeny postupným přidáváním 2 mM roztoku kovových iontů (kadmium nebo olovo) na S. aureus kultury.Zvyšující antimikrobiální účinek ampicilin, streptomycin, penicilin a tetracyklin (0, 10, 25, 50, 75, 150, 225 a 300 um) na rezistentních kmenů byla pozorována za použití metody růstových křivek. Významná inhibice růstu (ve srovnání s kontrolou) buněk rezistentních kadmia byl pozorován v přítomnosti všech čtyř různých antibiotik. Na druhé straně, přidání streptomycinu a ampicilinu neinhibuje růst olova rezistentního kmene. Další antibiotika stále toxické pro bakteriálních buněk. Významné rozdíly v morfologii buněčných stěn byly označeny změny ve tvaru buňky. Naše data ukazují, že přítomnost kovových iontů v městském prostředí, může přispět k rozvoji bakterií kmene rezistence na jiné látky, včetně antibiotik, které by mohly mít vliv na veřejné zdraví. (přeloženo strojově, pravopis nekontrolován).

Platinum-based cytostatics, such as cisplatin, carboplatin or oxaliplatin are widely used agents in the treatment of various types of tumors. Large amounts of these drugs are excreted through the urine of patients into wastewaters in unmetabolised forms. This phenomenon leads to increased amounts of platinum ions in the water environment. The impacts of these pollutants on the water ecosystem are not sufficiently investigated as well as their content in water sources. In order to facilitate the detection of various types of platinum, we have developed a new, rapid, screening flow injection analysis method with electrochemical detection (FIA-ED). Our method, based on monitoring of the changes in electrochemical behavior of analytes, maintained by various pH buffers (Britton-Robinson and phosphate buffer) and potential changes (1,000, 1,100 and 1,200 mV) offers rapid and cheap selective determination of platinum-based cytostatics and platinum chlorides, which can also be present as contaminants in water environments. Na bázi platiny cytostatika, jako je cisplatina, karboplatina a oxaliplatina jsou široce používané prostředky pro léčbu různých typů nádorů. Velké množství těchto léků jsou vylučovány močí pacientů do odpadních vod v nezměněné formě. Tento jev vede ke zvýšení množství platiny iontů ve vodním prostředí. Dopady těchto znečišťujících látek na vodní ekosystém, nejsou dostatečně zkoumány, jakož i jejich obsah ve vodních zdrojích. S cílem usnadnit detekci různých typů platiny, jsme vyvinuli novou, rychlou metodu analýzy vstřikování screening toku s elektrochemickou detekcí (FIA-ED). Naše metoda, založená na sledování změn v elektrochemickém chování analytů, které vedou různé pH pufry (Britton-Robinson a fosfátového pufru) a případné změny (1,000, 1,100 a 1,200 mV) nabízí rychlé a levné selektivní stanovení platinových cytostatik a platiny chloridů, které mohou být také přítomny jako nečistoty ve vodním prostředí.

In this study, we focused on microfluidic electrochemical analysis of zinc complexes (Zn(phen)(his)Cl-2, Zn(his)Cl-2) and ZnS quantum dots (QDs) using printed electrodes. This method was chosen due to the simple (easy to use) instrumentation and variable setting of flows. Reduction signals of zinc under the strictly defined and controlled conditions (pH, temperature, flow rate, accumulation time and applied potential) were studied. We showed that the increasing concentration of the complexes (Zn(phen)(his)Cl-2, Zn(his)Cl-2) led to a decrease in the electrochemical signal and a significant shift of the potential to more positive values. The most likely explanation of this result is that zinc is strongly bound in the complex and its distribution on the electrode is very limited. Changing the pH from 3.5 to 5.5 resulted in a significant intensification of the Zn(II) reduction signal. The complexes were also characterized by UV/VIS spectrophotometry, chromatography, and ESI-QTOF mass spectrometry. V této studii jsme se zaměřili na mikrofluidní elektrochemickou analýzu komplexů zinku (Zn (fenyl) (jeho) Cl-2, Zn (jeho) Cl-2) a ZnS kvantové tečky (QDS) za použití tištěných elektrod. Tato metoda byla zvolena z důvodu jednoduchému (snadné použití přístrojového vybavení) a variabilnímu nastavení toků. Byly studovány signály Redukční zinku v rámci přísně definovaných a kontrolovaných podmínek (pH, teplota, průtok, doba akumulace a aplikované potenciál). Ukázali jsme, že zvyšující se koncentrace komplexů (Zn (phen) (jeho) Cl-2, Zn (jeho) Cl-2) vede ke snížení elektrochemického signálu a významný posun potenciálu na více pozitivních hodnot. Nejpravděpodobnějším vysvětlením tohoto výsledku je, že zinek je silně vázána v komplexu a jeho rozložení na elektrodě je velmi omezený. Změna pH 3,5-5,5 vedlo k významnému zesílení Zn (II) signálu snížení. Komplexy byly také charakterizovány pomocí UV spektrofotometrie / VIS, chromatografie a ESI-QTOF hmotnostní spektrometrií. (Přeloženo strojově)

Carcinoma of prostate (CaP) is the second most frequent malignant tumor occurring in men in Europe. Currently there is discussion on a wide range of potential CaP markers.One of them—nonprotein amino acid sarcosine, also known as N-methylglycine was chosen as a challenge for the development of microfluidic system with isolation by modified paramagnetic microparticles. Therefore, the aim of this study was to design a low-cost, simple, and rapid microfluidic system based on sarcosine isolation with modified paramagnetic microparticles and subsequent analysis on the ion exchange LC. We modified Dowex microparticles with Fe2O3 nanoparticles. Our paramagnetic microparticles were able to establish the binding with sarcosine. Moreover, we designed microfluidic device for sarcosine determination. Analysis of samples was carried out with LOD of1 M of a sarcosine that is sufficient because it is similar to concentrations of a sarcosine observed in the CaP patients.Carcinoma of prostate (CaP) is the second most frequent malignant tumor occurring in men in Europe. Currently there is discussion on a wide range of potential CaP markers.One of them—nonprotein amino acid sarcosine, also known as N-methylglycine was chosen as a challenge for the development of microfluidic system with isolation by modified paramagnetic microparticles. Therefore, the aim of this study was to design a low-cost, simple, and rapid microfluidic system based on sarcosine isolation with modified paramagnetic microparticles and subsequent analysis on the ion exchange LC. We modified Dowex microparticles with Fe2O3 nanoparticles. Our paramagnetic microparticles were able to establish the binding with sarcosine. Moreover, we designed microfluidic device for sarcosine determination. Analysis of samples was carried out with LOD of1 M of a sarcosine that is sufficient because it is similar to concentrations of a sarcosine observed in the CaP patients.

Pathogenic bacteria have become a serious socio-economic concern. Immunomagnetic separation-based methods create new possibilities for rapidly recognizing many of these pathogens. The aim of this study was to use superparamagnetic particles-based fully automated instrumentation to isolate pathogen Staphylococcus aureus and its Zn(II) containing proteins (Zn-proteins). The isolated bacteria were immediately purified and disintegrated prior to immunoextraction of Zn-proteins by superparamagnetic beads modified with chicken anti-Zn(II) antibody. S. aureus culture was treated with ZnCl(2). Optimal pathogen isolation and subsequent disintegration assay steps were carried out with minimal handling. (i) Optimization of bacteria capturing: Superparamagnetic microparticles composed of human IgG were used as the binding surface for acquiring live S. aureus. The effect of antibodies concentration, ionic strength, and incubation time was concurrently investigated. (ii) Optimization of zinc proteins isolation: pure and intact bacteria isolated by the optimized method were sonicated. The extracts obtained were subsequently analyzed using superparamagnetic particles modified with chicken antibody against zinc(II) ions. (iii) Moreover, various types of bacterial zinc(II) proteins precipitations from particle-surface interactions were tested and associated protein profiles were identified using SDS-PAGE. Use of a robotic pipetting system sped up sample preparation to less than 4 h. Cell lysis and Zn-protein extractions were obtained from a minimum of 100 cells with sufficient yield for SDS-PAGE (tens ng of proteins). Zn(II) content and cell count in the extracts increased exponentially. Furthermore, Zn(II) and proteins balances were determined in cell lysate, extract, and retentate.

Carbonatites are characterized by the highest concentration of rare earth elements (REEs) of any igneous rock and are therefore good targets for REE exploration. Supergene, hydrothermal, and magmatic REE deposits associated with carbonatites have been widely studied. REE enrichment related to fluorapatite metasomatism in Fengzhen carbonatites in the North China block is reported in this study. REE minerals (monazite, britholite, and Ca-REE-fluorocarbonates) associated with barite and quartz formed as inclusions within the fluorapatite and externally on its surface. Monazite, allanite, barite, and quartz occur as rim grains on the edges of the fluorapatite. Zoned fluorapatite was observed and showed varying chemical composition. Based on back-scattered electron imaging, the dark domains with mineral inclusions contain lower Si (0.3–0.6 wt.% SiO2) and light REE (LREE) [0.36–1.54 wt.% (Y+LREE)2O3] contents than inclusion-poor areas [0.7–1 wt.% SiO2; 2.16–4.51 wt.% (Y + LREE)2O3]. This indicates a dissolution–re-precipitation texture. Different types of monazites were distinguished by their chemical compositions. Monazite inclusions have lower La2O3contents (~13 wt.%) and La/Ndcn (~3) ratios than those (18–26 wt.% and 10–14 for La2O3 and La/Ndcn, respectively) growing externally on the fluorapatite. REE enrichment in the metasomatic fluorapatites is related to different stages of carbonatitic liquids. The early carbonatite-exsolved fluids metasomatized the fluorapatites to form REE mineral inclusions. The late carbonatitic fluids from carbonatite magmas that underwent strong fractional crystallization were enriched in REEs, Al, and Fe and metasomatized the fluorapatites to produce allanite and monazite rim grains.

As a source of strategic commodities for high technologies, the deposits of rare earth elements (REEs) in China are a world-class phenomenon. The combination of the world's largest accumulation of REEs in the Bayan Obo deposit and the low cost of mining the extremely valuable heavy REEs from residual deposits makes China almost a monopoly producer. Research on a range of Chinese deposits shows that not only hypogene but also secondary processes create economic REE deposits. These deposits have characteristic REE distribution patterns, which range from primary light REE enrichment in carbonatites from the Himalayan Mianning–Dechang orogenic belt and in metamorphosed carbonatite and polyphase mineralization at Bayan Obo, through unusual flat REE patterns in carbonatites from the Qinling orogenic belt, to strong secondary heavy REE enrichment in residual clays from southern China.