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1.
This study was undertaken to provide reference values of chemical element mass fractions in intact bone of Reference (European Caucasian) Man/Woman. The rib bone samples investigated were obtained from autopsies of 84 apparently healthy 15–58-year-old citizens (38 females and 46 males) of a non-industrial region in the Central European part of Russia who had suffered sudden death. The mass fractions (mg/kg given on a wet mass basis) of 69 elements in these bone samples were measured by using neutron activation analysis with high-resolution spectrometry of short-lived and long-lived radionuclides, particle-induced gamma-ray emission, inductively coupled plasma atomic emission spectrometry, and inductively coupled plasma mass spectrometry including necessary quality control measures. Using published and measured data, mass fraction values of the 79 elements for the rib bone have been derived. Based on accepted rib to skeleton mass fractions and reference values of skeleton mass for Reference Man, the elemental burdens in the skeleton were estimated. These results may provide a representative bases for establishing related reference values for the Russian Reference Man/Woman and for revising and adding current reference values for the International Commission on Radiological Protection. The data presented will also be very valuable for many other applications in radiation protection, radiotherapy radiation dosimetry, and other scientific fields.  相似文献   

2.
Accumulation of rare earth elements in human bone within the lifespan   总被引:1,自引:0,他引:1  
For the first time, the contents of rare earth elements (REEs) in a rib bone of a healthy human were determined. The mean value of the contents of Ce, Dy, Er, Gd, La, Nd, Pr, Sm, Tb, and Yb (10 elements out of 17 total REEs), as well as the upper limit of means for Ho, Lu, Tm, and Y (4 elements) were measured in the rib bone tissue of 38 females and 42 males (15 to 55 years old) using inductively coupled plasma mass spectrometry (ICP-MS). We found age-related accumulation of REEs in the bone tissue of healthy individuals who lived in a non-industrial region. It was calculated that during a lifespan the content of REEs in a skeleton of non-industrial region residents may increase by one to two orders of magnitude. Using our results as indicative normal values and published data we estimated relative Gd accumulation in the bone tissue of patients according to magnetic resonance imaging with contrast agent and La accumulation in the bone tissue of patients receiving hemodialysis after treatment with lanthanum carbonate as a phosphate binder. It was shown that after such procedures contents of Gd and La in the bone tissue of patients are two to three orders of magnitude higher than normal levels. In our opinion, REEs incorporation may affect bone quality and health similar to other potentially toxic trace metals. The impact of elevated REEs content on bone physiology, biochemistry and morphology requires further investigation.  相似文献   

3.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

4.
The effect of age on the mass fraction of 19 chemical elements in the intact prostate of 50 apparently healthy 0–30-year-old males was investigated by neutron activation analysis with high-resolution spectrometry of short-lived radionuclides and inductively coupled plasma atomic emission spectrometry. Mean values (M ± standard error of the mean) for mass fraction (in milligrams per kilogram, on dry weight basis) of chemical elements were as follows: Al, 77?±?17; B, 1.31?±?0.29; Ba, 4.0?±?1.2; Br, 37.7?±?4.3; Ca, 1,536?±?189; Cl, 13,414?±?949; Cu, 12.3?±?2.1; Fe, 132?±?11; K, 11,547?±?468; Li, 0.064?±?0.009; Mg, 922?±?89; Mn, 1.88?±?0.16; Na, 9,834?±?411; P, 6,741?±?335; S, 8,034?±?251; Si, 199?±?34; Sr, 1.40?±?0.19; and Zn, 277?±?33. The upper limit of mean mass fraction of V was ≤0.24. This work revealed that there is significant tendency for the mass fractions of Ca, K, Mg, and Zn in the prostate tissue of healthy individuals to increase with age from the time of birth up to 30 years. It means that Ca, K, Mg, and Zn mass fractions in prostate tissue are the androgen-dependent parameters. Our finding of a positive correlation between the prostatic Zn and Ca, K, Mg, P, and S mass fractions indicates that there is a special relationship of Zn with some main electrolytes (Ca, K, and Mg) and with P- and S-containing compounds in the prostate. It was shown also that high levels of Al, B, Ba, Br, Cl, Li, Na, and Sr mass fraction in prostate tissue do not indicate a direct involvement of these elements in the reproductive function of the prostate.  相似文献   

5.
Rare earth elements (REEs) and Si in five species of seaweed, ambient surface seawaters, and suspended solid particles in the seawaters were determined separately. Inductively coupled plasma mass spectrometry (ICP-MS) was used for REEs and inductively coupled plasma emission spectrometry (ICP-ES) was used for Si in order to evaluate REEs as a tracer in seaweeds and to understand the source of inorganic elements, especially Si, in seaweeds. Two different REE patterns, one similar to that of the seawater solution and another resembling that of suspended particles, were observed in seaweeds, and the variation of REE patterns seems to show a clear dependence on the abundance of Si. The REE pattern and Si concentration seem to vary depending on the division: green and red algae showed REE patterns similar to that of suspended particles, but brown algae showed patterns closer to that of seawater solutions and relatively lower Si concentration. The possibility of contamination from silicate particles on the surface of seaweeds was ruled out for several reasons. Silicate particles, not dissolved silicate, have been identified as the direct source of REEs and Si in plants ( Fu et al. 1998 ), and seaweeds are no exception. We have to consider that seaweeds can take up Si from suspended particles through their blade or branches. From the appearance of tetrad-effect-like variation of REEs, Si is assumed to enter a dissolved state just before the particles are taken up. From the results of a sonication experiment, REEs, once taken up as silicate particles, seem to be separated from Si in the thallus.  相似文献   

6.
On the assumption that rare earth elements (REEs) are nontoxic, they are being utilized as replacements of toxic heavy metals in novel technological applications. However, REEs are not entirely innocuous, and their impact on health is still uncertain. In the past decade, our laboratory has studied the urinary excretion of REEs in male Wistar rats given chlorides of europium, scandium, and yttrium solutions by one-shot intraperitoneal injection or oral dose. The present paper describes three experiments for the suitability and appropriateness of a method to use urine for biological monitoring of exposure to these REEs. The concentrations of REEs were determined in cumulative urine samples taken at 0?C24?h by inductively coupled plasma atomic emission spectroscopy, showing that the urinary excretion of REEs is <2?%. Rare earth elements form colloidal conjugates in the bloodstream, which make high REEs accumulation in the reticuloendothelial system and glomeruli and low urinary excretion. The high sensitivity of inductively coupled plasma?Cargon emission spectrometry analytical methods, with detection limits of <2???g/L, makes urine a comprehensive assessment tool that reflects REE exposure. The analytical method and animal experimental model described in this study will be of great importance and encourage further discussion for future studies.  相似文献   

7.
To elucidate compositional changes of the ligament with aging, the authors investigated age-related changes of elements in the ligamentum capitis femoris (LCF) of monkeys with a wide range of ages by direct chemical analysis. Used rhesus and Japanese monkeys consisted of 9 males and 22 females, ranging in age from newborn to 31 years (average age?=?10.4?±?10.9 years). After incineration with nitric acid and perchloric acid, element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was found that the P content decreased significantly in the LCFs of monkeys with aging, but other six element contents, Ca, S, Mg, Zn, Fe, and Na, did not change significantly with aging. Assuming that the P content indicated the active cell density and the S content indicated the protein amount, an age-related change of the mass ratio of P/S was examined in the LCFs. The mass ratio of P/S decreased significantly in the LCFs in childhood. Regarding the relationships among elements, significant direct correlations were found among the Ca, P, S, and Mg contents in the LCFs. It was suggested that the active cell density of the connective tissue cells might decrease significantly in the LCF in childhood.  相似文献   

8.
The ontogenetic allometry of the lumbar region of 1913 humans (1228 females and 685 males), ranging from newborn to 21-year-old individuals, was studied by means of length, width, projected surface area and bone mineral density of the segment L2 - L4, obtained by dual X-ray absorptiometry (DXA). All these parameters were regressed to body mass and height of the individuals, considered alternatively as the independent variable. Firstly, we addressed the comparison between the results obtained on both sexes in order to elucidate whether ontogenetic differences existed. Length of the segments increased significantly faster in females than in males, independently whether the regression was made against body mass or height, while in both types of regression width scaled in males faster than in females. Regarding bone mineral density, although males increased bone mineral density faster than females, slope differences were not significant. However, y-interception was significantly higher in females than in males when bone mineral density was regressed to body mass. Results on length and width are compared with others from previous research on allometry. Finally, global results are discussed as regards the slope predictions for interspecific scaling.  相似文献   

9.
We investigated potential sex differences in bone resorption and the conservation of whole body bone mass in 24-week-old Sprague-Dawley rats maintained on a 1.0% calcium diet and then fed diets containing 0.02, 0.5, 1.0, or 1.75% calcium for 31 days. Lowering dietary calcium from 1.00% to 0.02% doubled whole skeleton bone resorption (urinary 3H-tetracycline loss). Female rats were more sensitive to calcium stress, exhibiting the maximal resorptive response when fed the 0.5% calcium diet, whereas the 0.02% calcium diet was required to elicit this response in males. Despite the evidence of increased bone resorption, whole skeleton mass was unchanged in females and was significantly increased in males, indicating that switching to even the 0.02% calcium diet did not result in an overt loss of total body bone mass. Compared with controls, the skeleton mass of females (97+/-1.4%) maintained on the 0.02% calcium diet was significantly lower than males (107+/-2.4%), again suggesting a greater impact of calcium deficiency in females. The calculation of the average percentage growth of selected individual bones in male rats indicated a proportional increase in bone mass between the axial and appendicular skeleton of approximately +4% and +18% in animals maintained on 0.02 and 1.75% diets, respectively. By comparison, female rats consuming the 0.02% calcium diet showed an average 14% loss in axial bone and 7.5% gain in appendicular bone mass. The results indicate increased sensitivity to dietary calcium deficiency in female rats which involves a significant loss in axial bone mass not observed in male rats maintained under similar dietary conditions.  相似文献   

10.
11.
BackgroundThe fern Dicranopteris linearis is a hyperaccumulator of rare earth elements (REEs), aluminium (Al) and silicon (Si). However, the physiological mechanisms of tissue-level tolerance of high concentrations of REE and Al, and possible interactions with Si, are currently incompletely known.MethodsA particle-induced X-ray emission (μPIXE) microprobe with the Maia detector, scanning electron microscopy with energy-dispersive spectroscopy and chemical speciation modelling were used to decipher the localization and biochemistry of REEs, Al and Si in D. linearis during uptake, translocation and sequestration processes.ResultsIn the roots >80 % of REEs and Al were in apoplastic fractions, among which the REEs were most significantly co-localized with Si and phosphorus (P) in the epidermis. In the xylem sap, REEs were nearly 100 % present as REEH3SiO42+, without significant differences between the REEs, while 24–45 % of Al was present as Al-citrate and only 1.7–16 % Al was present as AlH3SiO42+. In the pinnules, REEs were mainly concentrated in necrotic lesions and in the epidermis, and REEs and Al were possibly co-deposited within phytoliths (SiO2). Different REEs had similar spatial localizations in the epidermis and exodermis of roots, the necrosis, veins and epidermis of pinnae of D. linearis.ConclusionsWe posit that Si plays a critical role in REE and Al tolerance within the root apoplast, transport within the vascular bundle and sequestration within the blade of D. linearis.  相似文献   

12.
In recent years, bed bug (Hemiptera: Cimicidae) problems have increased dramatically in many parts of the world, leading to a renewed interest in their chemical ecology. Most studies of bed bug semiochemicals have been based on the collection of volatiles over a period of time followed by chemical analysis. Here we present for the first time, a combination of proton transfer reaction mass spectrometry and video analysis for real-time measurement of semiochemicals emitted by isolated groups of bed bugs during specific behavioural activities. The most distinct peaks in the proton transfer reaction mass spectrometry recordings were always observed close to the termination of mating attempts, corresponding to the defensive emissions that bed bugs have been suspected to exploit for prevention of unwanted copulations. The main components of these emissions were (E)-2-hexenal and (E)-2-octenal recorded in ratios between 1∶3 and 3∶1. In the current study, the quantity varied over 1000 fold for both of the compounds with up to 40 µg total release in a single emission. Males also emit defensive compounds due to homosexual copulation attempts by other males, and no significant differences were observed in the ratio or the amount of the two components released from males or females. In summary, this study has demonstrated that combining proton-transfer-reaction mass spectrometry with video analysis can provide detailed information about semiochemicals emitted during specific behavioural activities.  相似文献   

13.
有机配体对稀土元素在小麦体内积累和分异的影响   总被引:4,自引:0,他引:4  
丁士明  梁涛  闫军才  张自立  孙琴 《生态学报》2005,25(11):2888-2894
采用营养液培养和添加外源混合稀土等方法,研究了有机配体柠檬酸、EDTA和DTPA对稀土元素在小麦的根和叶中积累与分异的影响。结果表明,低浓度有机配体对小麦根和叶中的稀土元素,尤其是轻稀土元素的积累有轻微的促进作用,随浓度的升高则表现出显著的降低作用。有机配体对重稀土的作用比轻稀土强,使根和叶中稀土元素的分布曲线向重稀土相对亏缺的方向发展。3种配体对轻、重稀土分异的作用强度为:EDTA>DTPA>柠檬酸。通过VM INTEQ计算表明,在EDTA和DTPA作用下小麦叶中稀土元素的积累与轻、重稀土的分异主要由溶液中呈自由离子态稀土元素的含量和组成控制;柠檬酸作用下小麦叶中稀土元素的变化与自由离子态稀土的含量和组成关系较弱,推测REE-柠檬酸络合物可被小麦直接吸收并运转到小麦的叶中。  相似文献   

14.
Burying beetles reproduce on small vertebrate carcasses by exhibiting elaborate biparental brood care. Partner recognition in breeding Nicrophorus species (Coleoptera: Silphidae) relies substantially on information encoded in cuticular hydrocarbon profiles. Until recently, it was unknown whether breeding burying beetles also produce volatile low molecular weight substances and, if so, which functions can be attributed to such volatiles. The present study reports a survey of the volatiles released by males and females of Nicrophorus vespilloides Herbst in nonbreeding status and at different stages of breeding. Headspace analyses are performed by using solid phase micro‐extraction fibres and gas chromatography–mass spectrometry. The volatiles released by nonbreeding males and females include phenolic compounds, alcohols, aldehydes and ketones and are quite similar in both sexes. With the onset of breeding, the volatile profiles of males and females become distinct, with a number of female‐specific compounds occurring. An analysis of the anal secretions reveals the presence of some of the compounds previously detected in the headspace analysis. The specific chemical properties suggest that some of the volatiles may function against competitors and parasites, such as bacteria, fungi, nematodes and arthropods at the carcass breeding resource. By contrast, the emission of 4‐methyl branched esters by the females closely parallels the emission of the terpenoid methyl geranate and they may function together as a complex signal by the females. Signalling traits associated with biparental care and specific constraints associated with the ephemeral nature of the breeding resource may explain the occurrence of both groups of compounds in the volatile profiles.  相似文献   

15.
This study employs regression analysis to explore population and sex differences in the pattern of age-associated bone loss, as reflected by histomorphometric variables that are measures of intracortical and endocortical bone remodeling. A comparison of an African American sample from the Washington Park Cemetery in St. Louis, Missouri, and a European American rib sample composed of cadavers, autopsies, and forensic cases from Missouri reveals the existence of complex age-associated patterns for differences in measures of intracortical remodeling and cortical area. Females from the two samples express similar bone dimensions and dynamics. The African American females appear to lose more bone than their male counterparts, but this difference is absent in the European American sample. When age-associated patterns are considered, it is in the younger cohorts that African Americans exhibit greater relative cortical area than European Americans, but this is reversed in the older ages, when the latter group manifests greater bone mass. The European American males consistently differ in the slopes and intercepts for the variables compared to the other groups, and differences are highly significant with African American females, with the former group maintaining bone mass while the latter exhibit a more rapid bone loss. Achieving larger relative cortical area due to smaller endosteal area, coupled with better bone quality due to lower intracortical porosity early in life, may be a mechanism by which African Americans, especially females, maintain adequate bone mass in older ages, which buffers them from bone loss and related fragility fractures despite higher rates of intracortical remodeling and endosteal expansion later in life. These results suggest that both genetic and environmental factors are responsible for the differences in bone remodeling and bone mass observed between these samples.  相似文献   

16.
用感耦等离子体发射光谱法(ICP-AES)测定了东西赣南地区非稀土矿区和4处不同稀土矿区内,土壤-铁芒萁系统中La、Ce、Pr、Nd、Sm、Gd、Dy、Yb和Y的含量,并对其在土壤剖面层及铁芒萁植物体内的分布、迁移特征进行了研究,结果表明,土训层的底土层含量最高,但表土层铈相对富集、稀土元素总量(∑REE)在铁芒萁植物体内的分布规律是叶>根>茎>叶柄,单一稀土的分布规律各异,La、Ce、Pr、Nd的分布规律表现为:叶>根>茎>叶柄;Sm和Gd在不同采样点表现为叶>根>茎>叶柄或根>叶>茎>叶柄;Dy、Yb和Y均有3种不同的分布模式:叶>根>茎>叶柄、根>叶>茎>叶柄及根>茎>叶>叶柄,稀土元素在铁芒萁体内的迁移过程中,发生了明显的分馏作用,茎、叶柄、叶中的重稀土相对贫乏。  相似文献   

17.
Contents of fifteen rare earth elements (REEs) in the seeds ofsixty breeds of wheat collected from seed bank were measured byinductively coupled plasma mass spectrometry (ICP-MS). The distributionpatterns of contents of REEs in wheat seeds (n = 58) wereobserved and compared with their average level in soils (n =364). Differences among regions and between spring and winter wheat weretested. Comparison with literature data was also made. The results showthat the content of REEs in wheat seed ranges between10–11 g · g–1 and10–8 g · g–1, 3–4 orderof magnitudes lower than that in soils. The distribution patterns arethat light REEs enriched and the Eu-anomaly is weak, similar to the soilcase. No obvious differences were found among different regions andbreeds. The data obtained in this study represent the contents of thefifteen REEs in wheat seeds.  相似文献   

18.
HeLa S-3 cells were grown in minimal essential medium supplemented with 10% calf serum and 1 mM L-glutamine without adding any rare earth elements (REEs). Exponentially growing cells were collected, and dried materials were used to analyze their REE content by inductively coupled plasma-mass spectrometry. The results showed that the cells accumulated REEs in individually different manners; namely the accumulation ratio was higher in the lighter REEs than in the heavier REEs. To deduce the implication of the accumulation of REEs in HeLa cells, the accumulation ratios for REEs were compared with those of other biologically important elements. It was seen that the accumulation ratios obtained for REEs (from 31.8 [Ce] to 14.7 [Lu]) were intermediate among those of many bioelements: Fe (124), Mg (54.5), K (38.8), Cr (12.7), Na (11.8), Mn (11.3), Zn (10.7), Ca (8.8), and V (6.7).  相似文献   

19.
The release of tephritid sex pheromones depends significantly on the age of the male, the social context (presence of conspecifics) and chemical context (host volatiles). In this study, the influence of host fruit and conspecific (males and females) on the emission of the pheromonal compound 2-methyl-6-vinylpyrazine (2,6 mvp) by Toxotrypana curvicauda (Gerstaecker) males was investigated under laboratory conditions. Males were divided into one control group (nonexposed to treatment) and five experimental groups were placed 1 hr before volatile collection with: 1) host fruit (unripe papaya), 2) two females, 3) two males, 4) host fruit plus two females, and 5) host fruit plus two males. The volatiles were sampled by means of solid phase microextraction and analyzed with gas chromatography-mass spectrometry, with a focus on 2,6 mvp. Males emitted volatiles from the first day after adult emergence. The maximum peak and the temporal pattern of 2,6 mvp release were modified by the presence of host fruit and conspecific males or females. On day 5, males in the presence of fruit maintained a constant release of 2,6 mvp while the presence of conspecific caused a decrease of pheromone release. The release of 2,6 mvp was increased significantly in males exposed to both types of stimuli simultaneously. The stimuli (fruit and conspecifics) modified the release of 2,6 mvp, however the effect depended on male age.  相似文献   

20.
尿液在哺乳动物间的化学通讯中具有重要作用。本研究采用顶空固相微萃取-气质联用(HS-SPME-GC/MS)方法分析四川短尾鼩尿液中挥发性物质化学组成。结果表明,(1)通过检索国家标准与技术研究所质谱库,发现四川短尾鼩尿液中的化学成分主要为醛类、醇类、酮类、杂环、酯类、烷烃类、芳香烃类、含硫化合物、烯烃类、酚类等86种化合物,并且不同个体气味包含特有的挥发性化合物;(2)雌雄个体尿液中分别特有的挥发性化合物共计10种,其中雌性特有6种,雄性特有4种,表明四川短尾鼩尿液的化学成分存在性别差异。雌性的尿液中挥发性化合物76种,雄性只有33种,说明四川短尾鼩尿液中化学信号雌性多于雄性;(3)四川短尾鼩尿液中不同化学成分相对含量不同,同一组分在不同个体间相对含量存在差异。本研究有助于揭示四川短尾鼩尿液挥发性成分的化学通讯功能,并为引诱剂的研制提供基础资料。  相似文献   

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