AIMTo study the biochemistry of lanthanides, the cooperative action of inorganic and organic anti-tumor drugs.

METHODSA series of rare earth complexes were synthesized with Ln(NO3) 6H2O, Phen and 5-Fu. Their anti-tumor activity was measured by the improved MTT, SRB methods.

RESULTSThe formula of complex Ln[(Phen)2(5-Fu)3(NO3)](NO3)2(Ln = Y, La, Ce, Sm, Gd, Dy, Er; Phen = 1, 10-phenanthroline; 5-Fu = fluorouracil) was characterized by elemental analyses, molar conductivity, IR, TGA, and 13C NMR spectra. The preliminary biological activity studies indicated that Lanthanide complex has strong anti-tumor activity in vitro.

CONCLUSIONThe complex might have anti-tumor cooperation action.

Antineoplastic Agents ; chemical synthesis ; chemistry ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cerium ; chemistry ; Drug Synergism ; Dysprosium ; chemistry ; Erbium ; chemistry ; Fluorouracil ; chemistry ; Gadolinium ; chemistry ; Humans ; Lanthanoid Series Elements ; chemistry ; Lanthanum ; chemistry ; Phenanthrolines ; chemistry ; Samarium ; chemistry ; Structure-Activity Relationship ; Yttrium ; chemistry

OBJECTIVETo study the effects of aluminum citrate (AC), rare earth compounds (REC) and sodium selenite (SS) on the surface elements of chrysotile fibers and the inhibitory mechanisms of three compounds for chrysotile-induced biological activities.

METHODSAfter being soaked in 250, 500 and 1000 microg/ml aluminum citrate solutions, 125, 250, 500 and 1000 microg/ml mixed rare earths solutions or 125, 250, 500 and 1000 microg/ml sodium selenite solutions for 10 min or 1 hour, the fabrication and the levels of surface elements of chrysotile fibers were determined.

RESULTSAluminum citrate, mixed rare earths or sodium selenite all could be adsorbed by chrysotile fibers. After pretreatment of chrysotile fibers with aluminum citrate, mixed rare earths or sodium selenite solutions for 10 min or 1 hour, the corresponding elements or ion on the surface of chrysotile fibers increased with the increase of concentration of the solutions.

CONCLUSIONPretreatment of chrysotile with aluminum citrate, mixed rare earths or sodium selenite solutions can change the fabrication and the levels of surface elements of chrysotile fibers, and inhibit the biological activities of chrysotile by "sealing" some "active sites" on the surface of chrysotile fibers.

Asbestos, Serpentine ; chemistry ; toxicity ; Citric Acid ; chemistry ; Metals, Rare Earth ; chemistry ; Sodium Selenite ; chemistry

OBJECTIVETo study the relationship of hair content of rare earth elements (REEs) in the young children aged 0 - 3 years to that in their mothers living in a rare earth mining area of Jiangxi Province.

METHODSContent of five kinds of REEs, i.e., lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd) and samarium (Sm) were determined for the hair-root samples collected from 71 young children and 62 of their mothers by inductively coupled plasma source mass spectrometry (ICP-MS).

RESULTSThe mean hair content of REEs (e.g., La) was the highest (2,202.90 ng/g) in the young children living in the place nearest to the REE mining area, next (471.72 ng/g) was in those nearer to the REE mining area, and the lowest (97.37 ng/g) was in those in the control area. And, the hair content of REEs in the mothers was the same as that in their children, i.e, the mean content of La was the highest (1,510.21 ng/g) in high-exposure area, next (241.63 ng/g) was that in the low-exposure area, and the lowest (59.15 ng/g) was that in the control area, with P < 0.001. Pair-comparison analysis for the means showed that the average hair level of five kinds of REEs in the young children was two times high as their mothers' (P < 0.001). For example, the hair level of La was 533.83 ng/g in the young children and 279.78 ng/g in their mothers, respectively. Simple linear regression analysis showed that there was a significant correlation between the hair levels of each kind of REEs in the young children and those in their mothers, with a correlation coefficient of more than 0.75, e.g., that of La was 0.878 (P < 0.01).

CONCLUSIONSThe hair level of REEs can be used as a bio-marker to reflect body's level of exposure to REEs. The hair level of REEs in young children and their mothers decreased with the increase of the distance from their home to rare earth mining area. Young children living in the area with REEs mining may be the high-exposure population, and their hair level of REEs was significantly higher than that in their mothers and more attention should be paid to them.

Child, Preschool ; Environmental Exposure ; Hair ; chemistry ; Humans ; Infant ; Infant, Newborn ; Metals, Rare Earth ; analysis ; Mining ; Mothers

OBJECTIVETo evaluate the colouration of zirconia ceramic by adding three kinds of rare earth oxides. The influence of the pigments concentration on the mechanical properties and the microstructure was also analyzed.

METHODSAdded different concentrations of CeO(2), Er(2)O(3) and Pr(6)O(11) in tetragonal zirconia poly crystals stabilized with 3 mol% yttria (3Y-T2P) powder, compacted at 200 MPa using cold isostatic pressure, and sintered to 1 400 degrees C. The heating rate was 150 degrees C/h and the dwelling time was 2 hours. The chromaticity of sintered bodies was measured with chroma meter. The relative density, hardness, flexure strength and fracture toughness were investigated as well. The phase stability of the colorized and pure zirconia was evaluated by X-ray diffraction (XRD) using an automated diffractometer. The microstructures of the specimens were evaluated by scanning electron microscope (SEM).

RESULTSSeveral kinds of color achieved by the different pigments praseodym oxide, cerium oxide and erbium oxide were presented in the CIELab system. The a* value increased with the added amount of Er(2)O(3), while b* value rose with the increasing amount of CeO(2) and Pr(6)O(11). However, three pigments failed to decrease L* value and the sintered body appeared too bright. Adding three pigments influenced flexure strength of zirconia ceramic significantly, but had little influence on the hardness and fracture toughness. Microscopy revealed the relationship between the porosity and shapes of grains was correlated to strength of the diphase ceramics. No additional phase could be detected by XRD, except t-ZrO(2) in all colorized samples after sintering at 1 400 degrees C for 120 min.

CONCLUSIONSZirconia ceramic can be colorized by CeO(2), Er(2)O(3), and Pr(6)O(11). Pigments even in a small amount influence the mechanical properties of the colorized zirconia material, which necessitates further investigation.

Coloring Agents ; pharmacology ; Dental Porcelain ; chemistry ; Dental Stress Analysis ; Metals, Rare Earth ; pharmacology ; Oxides ; pharmacology ; Prosthesis Coloring ; Zirconium ; chemistry

The process in the studies on physiological effects of rare earth elements in plants and their action mechanisms were summarized in the aspects of seed germination, photosynthesis, mineral metabolism and stress resistance. And the applications of rare earth elements in traditional Chinese medicine (TCM) in recent years were also overviewed, which will provide reference for further development and application of rare earth elements in TCM.
Medicine, Chinese Traditional ; Metals, Rare Earth ; analysis ; metabolism ; Photosynthesis ; Plants, Medicinal ; chemistry ; growth & development ; metabolism ; Soil ; analysis

OBJECTIVE: To investigate the rare earth elements(REEs) contents and distribution characteristics in nasopharyngeal carcinoma( NPC) tissue in Gannan region. METHOD: Thirty patients of NPC in Gannan region were included in this study. The REEs contents were measured by tandem mass spectrometer inductively coupled plasma(ICP-MS/MS) in 30 patients, and the REEs contents and distribution were analyzed. RESULT: The average standard deviation value of REEs in lung cancer and normal lung tissues was the minimum mostly. Light REEs content was higher than the medium REEs, and medium REEs content was higher than the heavy REEs content. REEs contents changes in nasopharyngeal carcinoma were variable obviously, the absolute value of Nd, Ce, Pr, Gd and other light rare earth elements were variable widely. The degree of changes on Yb, Tb, Ho and other heavy rare earth elements were variable widely, and there was presence of Eu, Ce negative anomaly(δEu=0. 385 5, δCe= 0. 523 4). CONCLUSION The distribution characteristic of REEs contents in NPC patients is consistent with the parity distribution. With increasing atomic sequence, the content is decline wavy. Their distribution patterns were a lack of heavy REEs and enrichment of light REEs, and there was Eu , Ce negative anomaly.
Carcinoma ; Humans ; Lung ; Lung Neoplasms ; Metals, Rare Earth ; chemistry ; Nasopharyngeal Carcinoma ; Nasopharyngeal Neoplasms ; chemistry ; Reference Values ; Tandem Mass Spectrometry

OBJECTIVETo study the changes of immune function in mice offspring whose mothers were exposed to Rare Earth (RE)(NO(3))(3).

METHODSRE(NO(3))(3) was administered to mother mice after giving birth by gavage at dosages of 2, 20 and 200 mg/kg bw during breast-feeding period. The weights of spleen and thymus, the spleen plaque forming cells (PFC), the delayed type hypersensitivity (DTH) and the charcoal clearance of the offspring were determined.

RESULTSThe results obtained from the offspring after weaning showed that the body weight of offspring treated with 200 mg/kg RE(NO(3))(3) was 18.8% lower than that of the control group; at the dosage of 2 mg/kg, the number of IgM-PFC was increased by 82.7%; and at the dosage of 20 mg/kg the rate of clearance and clearance index were significantly higher than that of the control group. No difference in DTH was found in any treated group as compared to the control group. The results of offspring at three weeks after weaning showed that the number of IgM-PFC of the 20 and 200 mg/kg bw dose groups were 47.0% and 44.7% lower than that of control group respectively; the rate of clearance and clearance index of the 200 mg/kg group were significantly lower than that of the control group. No significant changes in DTH were observed in each exposed group.

CONCLUSIONRE(NO(3))(3) treatment affected the immune function of mice offspring which may caused by breast milk.

Animals ; Female ; Immunity ; drug effects ; Immunoglobulin M ; biosynthesis ; Metals, Rare Earth ; pharmacokinetics ; toxicity ; Mice ; Milk ; metabolism ; Organ Size ; drug effects ; Pregnancy

OBJECTIVETo develop a new nonisotopic detection method of enzyme-amplified time-resolved fluorescence (EATRF) or enzyme-amplified lanthanide luminescence (EALL) for nucleic acid hybridization assays, which can be applied extensively in clinical diagnosis.

METHODSThe method combines the high affinity of biotin-streptavidin system, amplification of enzyme, and inherent advantage of lanthanide chelate with the background elimination of time-resolved fluorescence detection. The conversion of 5-fluorosalicyl phosphate to 5-fluorosalicylic acid (5-FSA) by alkaline phosphatase. The salicylic acid product forms a luminescent ternary chelate with Tb3+ and EDTA.

RESULTSThe dynamic range of the standard curve of EATRFA for nucleic acid hybridization assay was very wide, the range was more than third order of magnitude. The detection sensitivity was about 10 pg of target sequence. When the known target sequence was 20, 10 and 2 ng, the ratio of measured amount to known amount was 110%, 90% and 115% respectively. The main experimental conditions, for example, the irradiating time of ultraviolet rays, the concentrations of biotinylated probe, AP-SA, 5-FSAP and Tb-EDTA and the methods of washing in the related steps, have been optimized. A new stable technology of fluorescence has been developted.

CONCLUSIONSEATRF detection for nucleic acid hybridization assays is a new sensitive simple method, which has a great prospect.

Alkaline Phosphatase ; analysis ; Blotting, Southern ; DNA ; genetics ; Fluoroimmunoassay ; methods ; Luminescent Measurements ; Metals, Rare Earth ; Nucleic Acid Hybridization ; methods ; Spectrometry, Fluorescence ; Substrate Specificity

OBJECTIVEThe aim of this survey was to investigate the level of contamination of the most consumed foods in China with 16 rare earth elements (REEs), and to provide the basic data for establishing and revising food safety standards for REEs.

METHODSSixteen REEs in foods were measured by inductively coupled plasma-mass spectrometry (ICP-MS) in the labs of the Centers for Disease Control and Prevention of four provinces and two municipalities, during 2009-2010.

RESULTS1 231 samples were analyzed and 19 121 concentration data of 16 REEs were collected. The REEs levels in the investigated foods varied significantly. The concentrations of cerium (Ce), dysprosium (Dy), yttrium (Y), lanthanum (La), and neodymium (Nd) were relatively high, while the remaining eleven REEs were at low levels. The mean values of total rare earth element oxides (REOs) in cereals, fresh vegetables, fresh aquatic products, fresh meats and eggs varied from 0.052 mg/kg to 0.337 mg/kg.

CONCLUSION16 REEs in the major foods were at very low contamination levels in the investigated regions.

Animals ; China ; Edible Grain ; chemistry ; Eggs ; Fishes ; Food Analysis ; Food Contamination ; Meat ; analysis ; Metals, Rare Earth ; chemistry ; Mollusca ; Swine ; Vegetables ; chemistry

OBJECTIVETo study the effects of rare earth exposure on human telomerase and apoptosis of human peripheral mononuclear cells (PBMNs).

METHODSRare earth mine lot in Xunwu county, the biggest ion absorptive rare earth mine lot of China, was selected as the study site. Another village of Xunwu county, with comparable geological structure and social environment was selected as the control site. Thirty healthy adults were randomly selected from the study site as exposure group and another 30 healthy adults randomly selected from the control site as control group. The blood content of 15 rare earth elements, including La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y, were determined by inductive coupled plasma-source mass spectrometry (ICP-MS). The total contents of rare earth elements in the blood were calculated. The TRAP and FCM assays were carried out to analyse the telomerase and apoptosis of human PBMNCs respectively.

RESULTSIn the exposure group, the concentration of La, Ce, Dy and Y were significantly higher (P<0.001), and Pr, Nd, Sm, Gd and Yb were higher than those in the control group (P<0.05). The total content of rare earth in the blood of exposure group showed significant difference compared with control group (P<0.001). Telomerase activity in PBMNs of the exposure group was higher than that in the control group (P<0.05); there were 11 adults in the exposure group (30 adults) and 5 adults in control group (30 adults) showed positive telomerase activity. The average age of the exposure group was (38.69 +/- 8.02) years-old, while the control group was (40.45 +/- 9.02) years-old (P >0.05). It was found that there was a significant relationship between telomerase activity and the total content of rare earth elements (P <0.01). 3. The proportion of apoptosis was not different between the two groups (P >0.05), but the cells in the S-phase and G2-M phase were increased (P <0.01) in the exposed group.

CONCLUSIONThe telomerase activity of PBMNs in the rare earth elements exposed group was higher than that of the control group, and there is no effect on apoptotic rate of PBMNs, but may promote the diploid DNA replication, and increase the percentage of G2/M and S phase cells.

Apoptosis ; drug effects ; Environmental Exposure ; adverse effects ; Female ; Humans ; Leukocytes, Mononuclear ; cytology ; enzymology ; Male ; Metals, Rare Earth ; adverse effects ; analysis ; Telomerase ; metabolism