ICPMS
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The As concentrations, along with 34 other elements, and the As speciation were investigated in wild-grown samples of the parasitic mushroom Tolypocladium ophioglossoides with inductively coupled plasma mass spectrometry (ICPMS) and high performance liquid chromatography coupled to ICPMS. The As concentrations were 0.070-3.44 mg kg-1 dry mass. More remarkable was the As speciation, where up to 56% of the extracted As were found to be an unknown As species, which was marginally retained under anion- and also cation-exchange conditions. After testing several different chromatographic settings, the compound was finally isolated and identified as 2-(sulfoxyethyl) trimethylarsonium ion (in short: arsenocholine-O-sulfate) with high resolution mass spectrometry. The compound was synthesized and further quantified in all investigated samples via ion-pair chromatography coupled to ICPMS. In addition to the high abundance of arsenocholine-O-sulfate in T. ophioglossoides, small amounts of this As species were also detected in one sample of the host mushroom, Elaphomyces asperulus. In a sample of another parasitic mushroom, Ophiocordyceps sinensis, arsenocholine-O-sulfate could not be detected, but the main species was another unknown compound that was oxidized to inorganic As(V) with hydrogen peroxide. This is the first discovery of arsenocholine-O-sulfate in nature. It is possible that it is present in many other organisms, at least in low concentrations, and just has not been detected there yet because of its unusual chromatographic behavior. The existence of arsenocholine-O-sulfate brings up questions again about the biotransformation pathways of As in the environment and the specific behavior of fungi.
Certification of trace metals in seawater certified reference materials (CRMs) NASS-7 and CASS-6 is described. At the National Research Council Canada (NRC), column separation was performed to remove the seawater matrix prior to the determination of Cd, Cr, Cu, Fe, Pb, Mn, Mo, Ni, U, V, and Zn, whereas As was directly measured in 10-fold diluted seawater samples, and B was directly measured in 200-fold diluted seawater samples. High-resolution inductively coupled plasma mass spectrometry (HR-ICPMS) was used for elemental analyses, with double isotope dilution for the accurate determination of B, Cd, Cr, Cu, Fe, Pb, Mo, Ni, U, and Zn in seawater NASS-7 and CASS-6, and standard addition calibration for As, Co, Mn, and V. In addition, all analytes were measured using standard addition calibration with triple quadrupole (QQQ)-ICPMS to provide a second set of data at NRC. Expert laboratories worldwide were invited to contribute data to the certification of trace metals in NASS-7 and CASS-6. Various analytical methods were employed by participants including column separation, co-precipitation, and simple dilution coupled to ICPMS detection or flow injection analysis coupled to chemiluminescence detection, with use of double isotope dilution calibration, matrix matching external calibration, and standard addition calibration. Results presented in this study show that majority of laboratories have demonstrated their measurement capabilities for the accurate determination of trace metals in seawater. As a result of this comparison, certified/reference values and associated uncertainties were assigned for 14 elements in seawater CRMs NASS-7 and CASS-6, suitable for the validation of methods used for seawater analysis.
- Publikační typ
- časopisecké články MeSH
Arsenic and its species were investigated for the first time in nine collections of Elaphomyces spp. ("deer truffles") from the Czech Republic with inductively coupled plasma mass spectrometry (ICPMS) and high-performance liquid chromatography coupled to ICPMS. The total arsenic concentrations ranged from 12 to 42 mg kg-1 dry mass in samples of E. asperulus and from 120 to 660 mg kg-1 dry mass in E. granulatus and E. muricatus. These concentrations are remarkably high for terrestrial organisms and demonstrate the arsenic-accumulating ability of these fungi. The dominating arsenic species in all samples was methylarsonic acid which accounted for more than 30% of the extractable arsenic. Arsenobetaine, dimethylarsinic acid, and inorganic arsenic were present as well, but only at trace concentrations. Surprisingly, we found high amounts of trimethylarsine oxide in all samples (0.32-28% of the extractable arsenic). Even more remarkable was that all but two samples contained significant amounts of the highly toxic trivalent arsenic compound methylarsonous acid (0.08-0.73% of the extractable arsenic). This is the first report of the occurrence of trimethylarsine oxide and methylarsonous acid at significant concentrations in a terrestrial organism. Our findings point out that there is still a lot to be understood about the biotransformation pathways of arsenic in the terrestrial environment. Graphical abstract Trimethylarsine oxide and methylarsonous acid in "deer truffles".
Magnesium (Mg2+) is the ubiquitous metal ion present in chlorophyll and bacteriochlorophyll (BChl), involved in photosystems in photosynthetic organisms. In the present study we investigated targets of toxic copper binding to the photosynthetic apparatus of the anoxygenic purple bacterium Rhodospirillum rubrum. This was done by a combination of in vivo measurements of flash photolysis and fast fluorescence kinetics combined with the analysis of metal binding to pigments and pigment-protein complexes isolated from Cu-stressed cells by HPLC-ICPMS (ICP-sfMS). This work concludes that R. rubrum is highly sensitive to Cu2+, with a strong inhibition of the photosynthetic reaction centres (RCs) already at 2 μM Cu2+. The inhibition of growth and of RC activity was related to the formation of Cu-containing BChl degradation products that occurred much more in the RC than in LH1. These results suggest that the shift of metal centres in BChl from Mg2+ to Cu2+ can occur in vivo in the RCs of R. rubrum under environmentally realistic Cu2+ concentrations, leading to a strong inhibition of the function of these RCs.
3. Aufl. mit alphabetischen Verzeichnis bearbeitet von R. Bartkowski LVI, 755 s. ; 25 cm
Die ICPM ist für den deutschsprachigen Raum die erste bereichsübergreifende Prozedurenklassifikation. Sie ermöglicht eine differenzierte klinische Dokumentation. Administrative Aufgaben wie die Meldung gemäß Paragr. 301 SGB V können abgeleitet werden. Durch die sechsstellige Differenzierung sind alle derzeitigen und zukünftigen Sonderentgelte und Fallpauschalen definierbar. Der OP-Schlüssel nach Paragr. 301 SGB V mit den fünfstelligen Operationskodes ist primär für die Leistungstransparenz und dieKommunikation zwischen Krankenhäusern und Krankenkassen konzipiert.
- MeSH
- klasifikace MeSH
- nemoc klasifikace MeSH
- Konspekt
- Lékařské vědy. Lékařství
- NLK Obory
- lékařství
Extensive information is available on total arsenic in particulate matter (PM), but little is known about the relative contribution of each individual species. Recent studies often focus on inorganic arsenic as arsenite and arsenate, neglecting the organoarsenicals, i.e., methylarsine, dimethylarsine, and trimethylarsine or the corresponding oxidized forms methylarsonate, dimethylarsinate, and trimethylarsine oxide, although they were already first detected in PM in the mid-1970s. This work presents results from more than 300 daily PM10 and further size-resolved atmospheric PM samples in the size range from 15 nm to 10 μm collected in an urban environment in Austria during the course of a year. An ion-exchange-HPLC (with anion and cation exchange columns) and an ICPMS/MS system were used to study the seasonal variations of total arsenic and all species known to exist in PM. Inorganic arsenic was present in significant amounts in all samples with highest concentrations during winter, but also all organoarsenicals were detected throughout the year. We show that their contribution cannot be ignored, as particles smaller than <1 μm can contain up to 35% of the water+H2O2 extractable arsenic as methylated species, but only dimethylarsinate showed a clear seasonal trend throughout the year.
- MeSH
- arsen analýza MeSH
- peroxid vodíku MeSH
- pevné částice MeSH
- roční období MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Rakousko MeSH
Toxicity of lanthanides is generally regarded as low, and they even have been suggested to be beneficial at low concentrations. This research was conducted to investigate effects of Lanthanum (La) on Desmodesmus quadricauda, a freshwater green microalga. The algal cultures were treated with nanomolar La concentrations under controlled environmentally relevant conditions. Intracellular localization of La was analyzed with μXRF tomography in frozen-hydrated samples. At sublethal concentration (128 nM) La was in hotspots inside the cells, while at lethal 1387 nM that led to release of other ions (K, Zn) from the cells, La filled most of the cells. La had no clear positive effects on growth or photosynthetic parameters, but increasing concentrations led to a dramatic decrease in cell counts. Chlorophyll fluorescence kinetic measurements showed that La led to the inhibition of photosynthesis. Maximal photochemical quantum yield of the PSII reaction center in dark-adapted state (Fv/Fm) decreased at > 4.3 nM La during the 2nd week of treatment. Minimum dark-adapted fluorescence quantum yield (F0) increased at > 13.5 nM La during the 2nd week of treatment except for control (0.2 nM La, baseline from chemicals) and 0.3 nM La. NPQ at the beginning of the actinic light phase showed significant increase for all the treatments. Metalloproteomics by HPLC-ICPMS showed that La binds to a >500 kDa soluble protein complex already in the sub-nM range of La treatments, in the low nM range to a small-sized (3 kDa) soluble peptide, and at >100 nM La additionally binds to a 1.5 kDa ligand.
- MeSH
- chemické látky znečišťující vodu toxicita MeSH
- chlorofyl metabolismus MeSH
- Chlorophyta účinky léků fyziologie MeSH
- fluorescence MeSH
- fotosyntéza účinky léků MeSH
- fotosystém II (proteinový komplex) účinky léků metabolismus MeSH
- lanthan metabolismus toxicita MeSH
- listy rostlin metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
Cíl. Ověřit přesnost metody "tlakového provokačního testu" v ultrazvukové diagnostice intrakraniální hypertenze u novorozenců s diagnózou posthemoragického hydrocefalu (PHH). Hlavním cílem bylo ověřit, zda klidový nebo kompresní index rezistence koreluje s přítomností intrakraniální hypertenze. Vedlejším cílem bylo zjištění závislosti mezi stupněm nitrolební hypertenze a velikostí komor, posouzení rychlosti rozvoje PHH a zjištění, ve kterém období se vyskytuje nejčastěji. Metoda. Vyšetřovaný soubor zahrnuje 52 dětí s diagnózou posthemoragického hydrocefalu (PHH), které byly vyšetřeny na našem pracovišti v letech 1999-2008. Průměrná porodní hmotnost dětí s PHH byla 1436 g v rozmezí 550-4090 g, medián 1150 g. Gestační stáří bylo 29,6 týdne (24.-41. týden), medián 28. týden. Celkem bylo v souboru 73 % dětí s velmi nízkou porodní hmotností (VLBW). Z celkového počtu 445 měření bylo ke statistickému zpracování vybráno 162 hodnot. Kritériem výběru bylo současné změření velikosti komor, klidového indexu rezistence (IR), indexu rezistence po stlačení velké fontanely (IRc) a zjištění intrakraniálního tlaku přímou metodou (ICPm). Výsledky. Posthemoragický hydrocefalus se vyvinul průměrně za 16 dnů po porodu, do 19. dne po porodu jsme prokázali intrakraniální hypertenzi u 95 % dětí. Z celkového počtu měření IRc (n = 162) jsme měli sedm falešně negativních a čtyři falešně pozitivní výsledky, při ICPm > 11 cm jsme měli jeden falešně negativní výsledek. Hodnoty IR u dětí s prokázanou intrakraniální hypertenzí byly v 71,3 % (107 měření) falešně negativní a nekorelovaly s hodnotou ICP (p > 0,5). Velikost komor neměla vztah k zjištěné hodnotě ICPm. Celková přesnost metody dosáhla 93,2 % při senzitivitě (95,5 %) a nízké specificitě (36,4 %). Závěr. Kompresní dopplerovská ultrasonografie dokáže s vysokou přesností stanovit přítomnost nitrolební hypertenze ještě před rozvojem klinických příznaků.
Aim. We wanted to try and verify the method of "pressure provocation test". The primary objective was to verify, if the basic and compressive resistive index correlates with the presence and eventually with the severity of intracranial hypertension. The secondary objective was to find relationship between the degree of intracranial hypertension and the diameter of cerebral ventricles, to asses the rapidity of PHH developement and to find out, in which period is PHH the most common. Method. In years 1999-2008, 52 children with diagnosis of posthemorrhagic hydrocephalus were examined in our department. The average birth weight in children with PHH was 1436 g (550-4090 g, median 1150 g). The average age was 29,6 weeks (24-41 weeks, median 28 weeks). Totally, 73% of children had very low birth weight (VLBW). From the total count of 445 examinations, 162 values were chosen for the next statistic processing. The criterium for choice was simultaneous measurement of ventricle diameters, basic resistive index (IR), compressive resistive index (IRc) and direct intracranial pressure measurement (ICPm). Results. Posthemorrhagic hydrocephalus developed on average in 16 days after the childbirth, till day 19 after the birth intracranial hypertension was proved in 95% of children. From the total count of measurements (n = 162), IRc were false negative (7) and false positive (5), in ICPm > 11 cm there was one false negative outcome. The IR values in children with proved intracranial hypertension were in 71.3% (107 measurements) false negative and didn?t correlate to the value of ICP (p < 0.5). There was no correlation found between the ventricle diameter and the measured value of ICPm. The total accuracy of the method achieved 93.2% with high sensitivity (95.5%) and low specificity (36.4%). Conclusion. Compressive doppler ultrasonography is able with high accuracy to determine the presence of intracranial hypertension even before development of clinical signs.
- MeSH
- dopplerovská echokardiografie metody využití MeSH
- hydrocefalus diagnóza etiologie MeSH
- intrakraniální hypertenze diagnóza etiologie MeSH
- intrakraniální krvácení etiologie komplikace MeSH
- kohortové studie MeSH
- kojenec MeSH
- lidé MeSH
- mozkové komory ultrasonografie MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
... Maternal and child health in the ICPM 121 -- Table 9.3. ... ... ICPM chapters and divisions 170 -- Table A3.1. ...
Health
205 s.
- Konspekt
- Veřejné zdraví a hygiena
- NLK Obory
- ekonomie, ekonomika, ekonomika zdravotnictví
- NLK Publikační typ
- studie