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PubMed1989

Multiple sequence elements of a single functional class are required for cyclic AMP responsiveness of the mouse c-fos promoter.

Agents that elevate the intracellular concentration of cyclic AMP (cAMP) rapidly and transiently induce expression of the c-fos proto-oncogene in BALB/c 3T3 cells. We show that the mouse c-fos promoter-enhancer region contains multiple elements that contribute to cAMP responsiveness of the promoter in transient expression assays. The most potent element was found to correspond to a previously mapped basal promoter element and protein-binding site located 65 base pairs upstream of the transcriptional initiation site. This element and two less potent sites contained a match to the cAMP response element (CRE) core sequence defined in several mammalian genes. The relative potencies of these elements corresponded with their relative affinities for cellular factors that bound to the CRE in vitro. Mutation of all three elements failed to abolish completely cAMP responsiveness of the c-fos promoter in the transient expression assay. However, we present evidence that this residual responsiveness may have been due to sequences present in vector DNA. Finally, we show, by using a new microinjection competition assay, that a double-stranded oligonucleotide carrying the major c-fos CRE is sufficient to block induction of the endogenous c-fos gene by cAMP. Therefore, induction of the endogenous gene requires positively acting cellular factors that interact with a single functional class of regulatory sites in the c-fos gene. Unrelated regulatory elements, such as the serum response element and putative AP-2 sites, are not by themselves sufficient to mediate the cAMP response.

Animals↗

PubMed1999

Trace elements in end-stage renal disease. 1. Methodological aspects and the influence of water treatment and dialysis equipment.

For human beings trace elements are essential nutrients with a gamut of functions. They are for instance indispensable components of many enzymes, so they have some regulatory functions and they may affect immune reactions and free radical generation. Altered blood levels of different trace elements have been described in patients with advanced renal failure and especially in those treated by different kinds of renal replacement therapy. Altered renal function may result in impaired renal excretion of trace elements and their accumulation or depletion in the body. The dialysate concentrate and water used for preparing the dialysate may be an important source of the accumulation or depletion of trace elements in dialyzed patients. The gain or loss of trace elements during dialysis depends on the gradient between the ultrafiltrable fraction of a particular element in serum and its concentration in the dialysis fluid, and also on the type and permeability of the dialysis membrane. There are some methodological problems concerning the handling and storing of blood samples and measurement techniques leading to the rather inconsistent results of different studies concerning trace elements in renal disease. Geographical variations and environmental contamination of soil and water and different dietary habits may significantly influence trace elements in these patients. The abnormalities of trace elements are primarily the result of uremia, and they may be further modified and sometimes greatly exacerbated by the dialysis procedure.

Artifacts↗

PubMedDate not supplied

Trace element contamination of total parenteral nutrition. 2. Effect of storage duration and temperature.

BACKGROUND: Patients who receive home total parenteral nutrition (TPN) frequently are supplied with solutions up to 30 days in advance of anticipated use. The purpose of this study was to determine the stability of trace elements relative to time and temperature conditions, in a typical adult TPN solution stored in a usual home environment by examining variations in delivery of intended trace elements and inadvertent trace element contamination. METHODS: Trace element concentrations were determined using inductively coupled plasma-mass spectrometry technology. The effect of the delivery apparatus, storage duration (36 hours or 30 days) after compounding, and storage temperature (4 degrees C or 20 degrees C) were examined. RESULTS: The delivery apparatus contaminated the delivered TPN solution with cobalt but did not alter trace elements formulated into the TPN solution. Storage duration and temperature significantly decreased three (Zn, Cu, and Mn) of the six trace elements formulated into the TPN solution. Higher temperatures and longer duration of storage accelerated this decrease. Boron, Al, V, Ti, Ba, Sr, and CO were the trace elements that appeared as contaminants during storage. Boron, Al, V, and Ti contamination decreased with higher temperatures and longer duration of storage. CONCLUSIONS: Longer storage duration and higher storage temperature progressively reduced the deliverable concentrations of trace elements specifically formulated into the TPN solution and also of those trace elements that were not formulated into the TPN solution but that appeared as contaminants.

Drug Contamination↗

PubMed2005

The Sinbad retrotransposon from the genome of the human blood fluke, Schistosoma mansoni, and the distribution of related Pao-like elements.

BACKGROUND: Of the major families of long terminal repeat (LTR) retrotransposons, the Pao/BEL family is probably the least well studied. It is becoming apparent that numerous LTR retrotransposons and other mobile genetic elements have colonized the genome of the human blood fluke, Schistosoma mansoni. RESULTS: A proviral form of Sinbad, a new LTR retrotransposon, was identified in the genome of S. mansoni. Phylogenetic analysis indicated that Sinbad belongs to one of five discreet subfamilies of Pao/BEL like elements. BLAST searches of whole genomes and EST databases indicated that members of this clade occurred in species of the Insecta, Nematoda, Echinodermata and Chordata, as well as Platyhelminthes, but were absent from all plants, fungi and lower eukaryotes examined. Among the deuterostomes examined, only aquatic species harbored these types of elements. All four species of nematode examined were positive for Sinbad sequences, although among insect and vertebrate genomes, some were positive and some negative. The full length, consensus Sinbad retrotransposon was 6,287 bp long and was flanked at its 5'- and 3'-ends by identical LTRs of 386 bp. Sinbad displayed a triple Cys-His RNA binding motif characteristic of Gag of Pao/BEL-like elements, followed by the enzymatic domains of protease, reverse transcriptase (RT), RNAseH, and integrase, in that order. A phylogenetic tree of deduced RT sequences from 26 elements revealed that Sinbad was most closely related to an unnamed element from the zebrafish Danio rerio and to Saci-1, also from S. mansoni. It was also closely related to Pao from Bombyx mori and to Ninja of Drosophila simulans. Sinbad was only distantly related to the other schistosome LTR retrotransposons Boudicca, Gulliver, Saci-2, Saci-3, and Fugitive, which are gypsy-like. Southern hybridization and bioinformatics analyses indicated that there were about 50 copies of Sinbad in the S. mansoni genome. The presence of ESTs representing transcripts of Sinbad in numerous developmental stages of S. mansoni along with the identical 5'- and 3'-LTR sequences suggests that Sinbad is an active retrotransposon. CONCLUSION: Sinbad is a Pao/BEL type retrotransposon from the genome of S. mansoni. The Pao/BEL group appears to be comprised of at least five discrete subfamilies, which tend to cluster with host species phylogeny. Pao/BEL type elements appear to have colonized only the genomes of the Animalia. The distribution of these elements in the Ecdysozoa, Deuterostomia, and Lophotrochozoa is discontinuous, suggesting horizontal transmission and/or efficient elimination of Pao-like mobile genetic elements from some genomes.

Amino Acid Motifs↗

PubMed2006

Bacterial repetitive extragenic palindromic sequences are DNA targets for Insertion Sequence elements.

BACKGROUND: Mobile elements are involved in genomic rearrangements and virulence acquisition, and hence, are important elements in bacterial genome evolution. The insertion of some specific Insertion Sequences had been associated with repetitive extragenic palindromic (REP) elements. Considering that there are a sufficient number of available genomes with described REPs, and exploiting the advantage of the traceability of transposition events in genomes, we decided to exhaustively analyze the relationship between REP sequences and mobile elements. RESULTS: This global multigenome study highlights the importance of repetitive extragenic palindromic elements as target sequences for transposases. The study is based on the analysis of the DNA regions surrounding the 981 instances of Insertion Sequence elements with respect to the positioning of REP sequences in the 19 available annotated microbial genomes corresponding to species of bacteria with reported REP sequences. This analysis has allowed the detection of the specific insertion into REP sequences for ISPsy8 in Pseudomonas syringae DC3000, ISPa11 in P. aeruginosa PA01, ISPpu9 and ISPpu10 in P. putida KT2440, and ISRm22 and ISRm19 in Sinorhizobium meliloti 1021 genome. Preference for insertion in extragenic spaces with REP sequences has also been detected for ISPsy7 in P. syringae DC3000, ISRm5 in S. meliloti and ISNm1106 in Neisseria meningitidis MC58 and Z2491 genomes. Probably, the association with REP elements that we have detected analyzing genomes is only the tip of the iceberg, and this association could be even more frequent in natural isolates. CONCLUSION: Our findings characterize REP elements as hot spots for transposition and reinforce the relationship between REP sequences and genomic plasticity mediated by mobile elements. In addition, this study defines a subset of REP-recognizer transposases with high target selectivity that can be useful in the development of new tools for genome manipulation.

Bacteria↗

PubMed2003

Differential modulation of androgen receptor action by deoxyribonucleic acid response elements.

In addition to the steroid response elements (SREs), which are recognized by several steroid receptors, a second class of DNA elements exhibiting selectivity for the androgen receptor (AR) and named androgen response elements (AREs) has been identified. Here we provide evidence for the differential role of these element classes in modulating AR function. AR complexes attached to response elements representative of each class were purified. Limited protease digests of ARE- or SRE-bound AR complexes led to the generation of different patterns, in line with differential accessibilities. In transactivation assays, mutations in the AR dimerization interface of the DNA-binding domain had various effects, depending on the response elements tested. The R598D mutant displayed much enhanced activity on SREs, whereas far less effect was seen on the selective AREs. The A596T mutant had reduced activity on AREs but not on SREs. Ectopic expression of the coactivators transcriptional intermediary factor 2 (TIF2) and ARA55 stimulated AR activity to different extents, depending on the response element. When using cysteine-rich secretory protein 1 (CRISP-1) SRE as reference, the most significant difference was observed with Pem ARE-2. A differential response of each element class was furthermore observed in the presence of two enzymes involved in the sumoylation pathway. Ubiquitin-conjugating enzyme 9 (Ubc9) overexpression enhanced AR action conveyed by SREs, whereas little effect was seen on Pem ARE-1 and repression on Pem ARE-2. Protein inhibitor of activated STAT (PIAS)xalpha overexpression had little influence on SRE-mediated AR activity but was repressive when using AREs. Altogether, these results demonstrate that DNA response elements play an important modulatory role in transmitting AR action and may be determinative for specificity of gene expression in cell or tissue types.

Animals↗

PubMed2003

Deoxyribonucleic acid response element-dependent regulation of transcription by orphan nuclear receptor estrogen receptor-related receptor gamma.

The estrogen receptor-related receptor gamma (ERR gamma/ERR3/NR3B3) is the newest member of the ERR subfamily that also includes ERR alpha and ERR beta. All three isoforms share a high degree of amino acid identity especially in the DNA binding domain. ERR gamma is a constitutively active transcriptional activator that regulates reporter elements driven by steroidogenic factor 1 response element (SF-1RE) and estrogen response element. However, it has the highest potency on a derivative of SF-1RE present in the small heterodimer partner gene promoter called sft4 and unlike ERR alpha and -beta, it fails to activate a palindromic thyroid hormone response element. To investigate the mechanism behind this response element-specific differential transcriptional activity of ERR gamma, the interactions of ERR gamma and the aforementioned response elements was monitored. EMSA and chromatin immunoprecipitation assays demonstrated that ERR gamma binds to sft4, SF-1RE, and palindromic thyroid hormone response element albeit with different degrees of affinity, but causes hyperacetylation of sft4 and SF-1RE templates only. Limited proteolysis assays showed that ERR gamma, bound to different elements, shows differential trypsin sensitivity. A search for novel coregulators of ERR gamma led to the identification of receptor interacting protein 140 as a potent corepressor and peroxisome proliferator-activated receptor gamma coactivator 1 as a potent coactivator of ERR gamma. DNA-dependent pull-down and transient transfection assays demonstrated that, on different DNA elements, ERR gamma exhibits differential cofactor interactions, which in turn dictate its transcriptional activity. Because ERR gamma shows a similar tissue distribution as peroxisome proliferator-activated receptor gamma coactivator 1 and receptor interacting protein 140, these two coregulators may act as key components of ERR gamma-mediated transcription.

Adaptor Proteins, Signal Transducing↗

PubMed2002

Uptake and distribution of trace metal elements in wheat seedlings.

The uptake and distribution of eight metallic elements were examined in wheat seedlings for a period of 12 d with a radioactive multitracer technique. The radioactive nuclides of the seedlings were simultaneously determined by gamma-ray spectrometry. All of the elements studied were taken up by the wheat seedlings and mainly accumulated in the roots. Only some elements were transported to shoots and leaves of the seedlings or bound to leaf proteins, and two elements were transported into the chloroplast. Uptake of most elements reached a maximum on the fifth or the eighth day and then gradually decreased afterward. In the cases of 95mTc and 72Se, the uptake increased continuously within 12 d without the peak uptake. The change of elemental concentrations was dependent on uptake and excretion rates. The dynamics of metal elements taken up by the wheat seedlings and their distribution in roots, shoots, and leaves were different for each element, suggesting that it may depend on the characteristics of the elements.

Chloroplasts↗

PubMed2005

Molecular characterization and chromosomal distribution of Galileo, Kepler and Newton, three foldback transposable elements of the Drosophila buzzatii species complex.

Galileo is a foldback transposable element that has been implicated in the generation of two polymorphic chromosomal inversions in Drosophila buzzatii. Analysis of the inversion breakpoints led to the discovery of two additional elements, called Kepler and Newton, sharing sequence and structural similarities with Galileo. Here, we describe in detail the molecular structure of these three elements, on the basis of the 13 copies found at the inversion breakpoints plus 10 additional copies isolated during this work. Similarly to the foldback elements described in other organisms, these elements have long inverted terminal repeats, which in the case of Galileo possess a complex structure and display a high degree of internal variability between copies. A phylogenetic tree built with their shared sequences shows that the three elements are closely related and diverged approximately 10 million years ago. We have also analyzed the abundance and chromosomal distribution of these elements in D. buzzatii and other species of the repleta group by Southern analysis and in situ hybridization. Overall, the results suggest that these foldback elements are present in all the buzzatti complex species and may have played an important role in shaping their genomes. In addition, we show that recombination rate is the main factor determining the chromosomal distribution of these elements.

Animals↗

PubMed1976

[Influence of industrialization on trace element concentration in human lungs].

INTRODUCTION: People who spend their entire lives in highly industrialized regions are in danger of accumulating trace elements by inhalation as a result of the increased amounts of factory-produced smoke. In order to test the environmentally accumulated trace elements in lungs, lung samples of patients who lived their entire lives in the industrial area of Duisburg were compared with those of patients from the less industrialized areas of Cologne and surroundings. MATERIAL AND METHOD: Five patients were studied who lived in Duisburg and died at 50-68 years but not primarily as a result of lung diseases. From each patient five samples of the left lung were removed at autopsy. Lungs from 18 patients who died in Cologne were also examined. From each of the latter 2 samples were removed from the left lung. All samples were studied by means of neutron activation analysis and the following elements analysed: Co, Fe, Rb, Se, Cr, Cs, Sb, Sc, Zn and Al. The Al-concentration was analysed only in patients aged 50-68 years. RESULTS: The values of the non-essential Sc, Al and Cs and of the essential trace elements Co were found to be appreciably higher in the samples from Duisburg than in those from Cologne. Sc in the samples from the highly industrialized area was increased up to a factor of 100, Cs, Al and Co to a factor of 10. In the lungs of adults in Duisburg, aged 50-68 years, the concentration of Sc was more than 1,000 times greater than in lungs of children in Cologne, aged 0-10 years. In all samples from Duisburg, the rare element Eu was detectable by means of neutron activation analysis but could not be detected in a sample from Cologne. DISCUSSION: It is likely that the different uptakes of trace elements in the lungs depend on correspondingly different concentrations of the elements in the air. The extensive accumulation, especially of the non-essential elements, in the lungs should be an incentive to examine possible detrimental effects on human health in the future. The element Sc which was strikingly accumulated in the lungs and which can be easily measured by neutron activation analysis might be used as a standard for estimating the extent of environmental pollution.

Aged↗

PubMed2003

Major and trace elemental analysis in milk powder by inductively coupled plasma-optical emission spectrometry (ICP-OES) and instrumental neutron activation analysis (INAA).

Major and trace element in seven different kinds of milk powder were studied. The concentration of 24 elements were determined by ICP-OES method, from these elements 9 elements determined by INAA. The determination of trace element contents of foodstuffs, especially milk as daily drink for all peoples age which being a complex food has great importance. The elemental analysis of milk is important both as an indicator of environmental contamination and because milk is a significant pathway for toxic metal intake and a source of essential nutrients for humans. The major elements are Ca, K, Mg, Na, P and S. While trace element are B, Ba, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Sb, Se, Sn, Sr, V, W and Zn. ICP-OES technique is shown to be a powerful tool for trace determinations in powder samples. This is shown by its use for analysis of a series of the milk powders mentioned and comparative results of other direct technique such as instrumental neutron activation analysis. Analysis of both standard reference material A-11 milk powder and NBS Orchard leaves for quality accurance had been completed, and used for a relative method calculate. The importance of the major and trace elements to human health was discussed.

Animals↗

PubMed2003

[Age-dependent reconstruction of element status in Magadan inhabitants].

On the base of macro- and microelements' concentration in hair of Magadan's inhabitants there were analyzed the changes of aged people's element status. It has been shown that with age, differently directed reconstruction happened, leading to accumulation of one elements and decrease of concentration of others in inhabitants' hair. Elements, undergoing natural age reconstruction, may be considered as indicators and initiators of aging. We have allocated two groups of elements, in dependence on changes' direction. The first group is the main one; Na, K, Ca, Se, As, Mg, Mn, Fe, Zn belong to this group; their level in hair is increasing with age. Taking into account the excretory function of hair, accumulation of named elements is considered as aged removing of these elements out of organism. The exception is the toxic As: its superfluous concentrations in hair reflect the accumulation As in the internal environment of organism. Elements (Cr, Si), concentration of which in hair is decreasing with age, belong to the second group. On the base of literary data, the decreasing of named elements in hair must be interpreted as their programmed decreasing in the organism of aged people. Hence, in aged people there is seen the generalized decreasing of the most studied essential macro- and microelements in the organism. The exception is As, concentration of which is increasing in aged people. The age disorder of element homeostasis may serve as a predictor of "normal" diseases and may be one of pathophysiological mechanisms of aging.

Adult↗

PubMedDate not supplied

Bermudagrass management in the southern Piedmont, USA: IX. Trace elements in soil with broiler litter application.

An understanding of the long-term cycling of trace elements in soil with broiler litter fertilization under various forage utilization strategies is needed to develop sustainable agricultural production systems. We evaluated differences in Cu, Mn, Zn, and six other trace elements in response to 5 yr of bermudagrass [Cynodon dactylon (L.) Pers.] management varying in fertilization and harvest strategies on a Typic Kanhapludult in Georgia. Chicken (Gallus gallus) broiler litter was a significant source of trace elements that led to 3.4 +/- 0.5 times higher Cu, 2.0 +/- 0.3 times higher Mn, and 2.1 +/- 0.2 times higher Zn in the surface 3 cm of soil than when forage was fertilized inorganically. There were variable effects of broiler litter fertilization on other trace elements, depending upon element, depth of sampling, and forage utilization strategy. Concentrations of all trace elements in soil were below levels considered toxic to plants. Soil at a depth of 0 to 3 cm under grazed paddocks had 33 +/- 5% greater Cd, 18 +/- 1% greater Cr, 53 +/- 24% greater Cu, and 24 +/- 7% greater Zn compared with unharvested and hayed management. Trace elements in soil were unaffected whether forage was unharvested or removed as hay. These results suggest that broiler litter is a significant source of several trace elements and that ruminant processing of forage and subsequent deposition of excreta on the paddock allow these trace elements to accumulate more at the soil surface where they might interact with the high concentration of organic matter.

Agriculture↗

PubMed2004

Presence of insertion sequences (IS elements) in group B streptococci of bovine origin.

BACKGROUND & OBJECTIVES: Streptococcus agalactiae (group B streptococci, GBS) is one of the leading causative agents of human and animal infections. Recently it was demonstrated that integration of different IS elements could inactivate some of the GBS virulence properties. The presence of IS elements in human isolates has been studied while the bovine isolates were not investigated till now. The objective of the study was to perform IS analysis of a large number of bovine GBS and to use the IS elements for classification and molecular epidemiology of GBS strains. METHODS: A total of 101 GBS isolates obtained from the dairy cows were tested. These were analyzed by PCR and multiplex PCR. Southern hybridization was accomplished with the Enzo(TM) DNA Labeling and Detection Kit. The computer techniques were used for selection of the specific primers and for analysis of the sizes of PCR products. RESULTS: GBS isolates collected at three different dairy farms were studied for the presence of IS elements. Multiplex PCR was used for the fast screening. It was found that IS861 presented in 29 GBS isolates (28.7%), IS1548 in 9 (8.9%), ISSa4 in 48 (47.5%) and IS1381 in 26 isolates (25.7%). A total of 28 bovine GBS isolates (27.7%) did not possess any of the IS elements, 36 (35.6%) possessed, 35 (34.7%) possessed two and 2 (1.9%) possessed three different IS elements. The GBS with four different IS elements were not found. Taken together, 10 different variants of GBS strains were discovered. Two out of 10 variants being specific for 51 isolates (50.5%) were predominant in bovine GBS. The results of the study demonstrated that the presence of IS elements significantly varied in bovine GBS. INTERPRETATION & CONCLUSION: The present data demonstrated that variants of IS elements present in GBS genome could be used as effective criteria for molecular epidemiology. In future this approach could probably be used as an additional tool for the epidemiological control and prevention of other bacterial infections.

Animals↗

PubMed1992

Response elements of the androgen-regulated C3 gene.

Intron and 5'-flanking regions of the androgen-regulated C3 subunit gene contain potential cis-acting transcription control sequences including several 15-base pair (bp) partial palindromes resembling response elements for glucocorticoid (GRE) and progesterone (PRE) receptors. Specific DNA binding of the androgen receptor (AR) and androgen-dependent activation of transcription indicate that some of these GRE/PRE-like sequences are capable of functioning as androgen response elements (ARE). A 0.3-kilobase pair (kbp) 5'-flanking fragment including the promoter region contains one such sequence (element A) and a 0.5-kbp region of the first intron contains two sequences (elements B and C). Androgen-dependent enhancement of transcription was assayed by cotransfection of CV1 cells with a rat AR expression vector, pCMVrAR, and C3 genomic fragments or synthetic elements cloned into the reporter vector ptkCAT. Enhancement of chloramphenicol acetyltransferase activity with the 0.5-kbp first intron fragment was 16 +/- 4-fold, while with the 0.3-kbp 5'-flanking fragment no response was detected and element C alone was greater than B or A. Binding of AR in the mobility shift assay correlated with androgen-dependent enhancement of chloramphenicol acetyltransferase activity. The intensity of transcriptional enhancement with the 0.5-kbp intron fragment suggested that other regulatory sequences within this intron region potentiated the ARE activities of elements B and C. ARE activity of the strongest C3 gene response element (C) was similar to that of a potent GRE (element M) of the mouse mammary tumor virus gene.

Amino Acid Sequence↗

PubMed2004

[Alu elements in the human genome].

BACKGROUND: The sequencing of the human genome has revealed that almost half of the genome consists of interspersed repeats. Among the different types of interspersed repeats in humans, Alu elements are the most frequent ones, and new Alu elements are still integrated into new positions in the humane genome. In this review some consequences of this Alu activity are discussed. The first part of the review is focused on Alu element activity that causes genetic disease while the use of Alu elements as genetic tools for several purposes is discussed in the last part. MATERIALS AND METHODS: This review article is based on a literature search on Medline. RESULTS AND INTERPRETATION: Alu elements cause disease by two different mechanisms. A de novo insertion of an Alu element into, or close to, a gene may disrupt its normal function, while homologous recombination between two Alu elements may result in deletions or duplications that cause genetic disease. The high density of Alu elements in the human genome combined with their absence in non-primate species make them useful as genetic tools. Alu elements also represent "molecular fossils" that give phylogenetic information about primates as well as information about historical DNA rearrangements in the human genome.

Alu Elements↗

PubMed2004

In vitro clearance of trace elements via continuous renal replacement therapy.

OBJECTIVE: Trace element loss during continuous renal replacement therapy in patients with acute renal failure has not been quantified sufficiently. DESIGN: Trace element loss was quantified using an in vitro model of continuous venovenous hemofiltration. Bovine blood was used for the experiment, and the plasma was analyzed for its chromium, copper, selenium, manganese, and zinc content. Two different polysulfone hemodiafilters, a low-flux F8 and high-flux F70 were used, and tested at two different ultrafiltrate flow rates of 1 L/hr and 2 L/hr, respectively. Trace element concentrations in the plasma and ultrafiltrate were analyzed using inductively coupled plasma mass spectrometry. The sieving coefficient and clearance of each trace element were calculated and compared between the two hemodiafilters. SETTING: In vitro bovine model of continuous venovenous hemofiltration. PATIENTS OR OTHER PARTICIPANTS: Not applicable. RESULTS: Mean sieving coefficients of both F8 and F70 hemodiafilters were similar for each trace element. Copper, chromium, manganese, selenium, and zinc all were detected in the ultrafiltrate. Estimated trace element loss using typical trace element blood concentrations and study-derived sieving coefficients suggest that daily losses of selenium are greater than what is replenished with a standard daily trace element supplement in total parenteral nutrition. CONCLUSION: These data suggest that the degree of continuous venovenous hemofiltration clearance chromium, copper, selenium, manganese, and zinc differ between elements and that selenium and copper might need to be replaced with doses that exceed typical supplementation guidelines.

Acute Kidney Injury↗

PubMed2004

[Preliminary attempt at the speciation of 25-elements in the Chinese medicinal herbs].

OBJECTIVE: To make an attempt at the multi-element speciation in the Chinese medicinal herbs by determining the concentrations of 25 elements in different extraction solutions. METHOD: Firstly, five Chinese medicinal herbs (Buddleja officinalis, Dictamnus dasycarpus, Myristica fragrans, Albizia judibrissin and Inula japonica) from the same region of China were treated to obtain water-soluble phase, lipid-soluble phase and non-soluble phase by water extraction, organic solvent extraction and acid digestion, respectively. Secondly, Phytolacca acinosa, a Chinese medicinal herb collected from 9 regions of China, was extracted by 0% EtOH, 50% EtOH, 75% EtOH, 95% EtOH, respectively, referring the Chinese Pharmacopoeia. Finally, the concentrations of 25 elements, such as Be, Cr, Cu, Zn, Ge, Sr, Y, Mo, Cd, Tl, Pb and REEs, in the above three phases were determined by ICP-MS. RESULT: Under the optimal conditions, all the 25 elements could be determined with detection limits ranged from 0.003 to 0.71 ng x g(-1). The average recoveries of the elements in P. acinosa were 88% approximately 119%, with the relative standard deviations 1.7% approximately 13.3%. It was observed that the determined 25 elements distributed in all the water-soluble, lipid-soluble and non-soluble phases, indicating that the inorganic species, organicspecies, as well as the protein bound species were coexisted in the herbs. Big differences of the element extraction rates could be found by using different ethanol solutions. CONCLUSION: With the aid of the obtained results, we may increase the extraction of necessary elements while decrease that of the toxic elements from the herbs by choosing a suitable solvent during the drug production.

Buddleja↗