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1.
Nicholas G. Paltridge Paul J. Milham J. Ivan Ortiz-Monasterio Govindan Velu Zarina Yasmin Lachlan J. Palmer Georgia E. Guild James C. R. Stangoulis 《Plant and Soil》2012,361(1-2):261-269
Background and aims
Crop biofortification programs require fast, accurate and inexpensive methods of identifying nutrient dense genotypes. This study investigated energy-dispersive X-ray fluorescence spectrometry (EDXRF) for the measurement of zinc (Zn), iron (Fe) and selenium (Se) concentrations in whole grain wheat.Methods
Grain samples were obtained from existing biofortification programs. Reference Zn, Fe and Se concentrations were obtained using inductively coupled plasma optical emission spectrometry (ICP-OES) and/or inductively coupled plasma mass spectrometry (ICP-MS). One set of 25 samples was used to calibrate for Zn (19–60?mg?kg–1) and Fe (26–41?mg?kg–1), with 25 further samples used to calibrate for Se (2–31?mg?kg–1 ). Calibrations were validated using an additional 40–50 wheat samples.Results
EDXRF limits of quantification (LOQ) were estimated as 7, 3 and 2?mg?kg–1 for Zn, Fe, and Se, respectively. EDXRF results were highly correlated with ICP-OES or -MS values. Standard errors of EDXRF predictions were ±2.2?mg Zn kg–1, ±2.6?mg Fe kg–1, and ±1.5?mg Se kg–1.Conclusion
EDXRF offers a fast and economical method for the assessment of Zn, Fe and Se concentration in wheat biofortification programs. 相似文献2.
Copper,zinc, and selenium in whole blood and thyroid tissue of people with various thyroid diseases 总被引:1,自引:0,他引:1
We investigated the possible differences among the concentrations of copper, zinc, and selenium, and their mutual relations
in the whole blood and thyroid tissue of patients with various thyroid disorders. Trace elements were determined by total-reflection
X-ray fluorescence. The mean levels of these metals in blood as well as the mean Cu/Zn, Cu/Se, and Zn/Se ratios in the patients
with thyroid cancer were significantly higher that in other patients and the control groups. However, the mean Zn and Se concentrations
in the thyroid cancer tissue were significantly lower than in the thyroid tissue of other patients. In addition, the mean
Cu/Zn and Cu/Se ratios in the thyroid cancer tissue were significantly higher than in the patients with other thyroid diseases.
We confirm that the highest levels of copper and zinc as well as the Cu/Zn, Cu/Se, and Zn/Se ratios in the whole blood of
the patients with thyroid cancer may suggest the progression of the proliferation process in the thyroid gland. We suggest
that the low concentrations of zinc and selenium in the thyroid tissue confirm their participation in the carcinogenic process. 相似文献
3.
Malvin Torsvik Amanda Häggblom Geir Egil Eide Erich Schmutzhard Kaare Vetvik Andrea Sylvia Winkler 《BMC endocrine disorders》2008,8(1):1-10
Background
Age- and sex-specific reference intervals are an important prerequisite for interpreting thyroid hormone measurements in children. However, only few studies have reported age- and sex-specific pediatric reference values for TSHbasal (TSH), free T3 (fT3), and free T4 (fT4) so far. Reference intervals are known to be method- and population-dependent. The aim of our study was to establish reference intervals for serum TSH, fT3, and fT4 from birth to 18 years and to assess sex differences.Methods
2,194 thyroid hormone tests obtained from a hospital-based pediatric population were included into our retrospective analysis. Individuals with diagnoses or medications likely to affect thyroid function were primarily excluded, as well as the diagnostic groups, if different from the purely healthy subgroup (n = 414). Age groups were ranging from 1 day to 1 month, 1 – 12 months, and 1 – 5, 6 – 10, 11 – 14, and 15 – 18 years, respectively. Levels of fT3, fT4 and TSH were measured on Advia® Centaur? automated immunoassay system.Results
The final sample size for reference data creation was 1,209 for TSH, 1,395 for fT3, and 1,229 for fT4. Median and 2.5/10/25/75/90/97.5 percentiles were calculated for each age group. Males had greater mean fT3 concentrations than females (p < 0.001). No sex-differences were found for TSH and fT4 between age-matched serum samples. Median concentrations of fT3, fT4 and TSH were greatest during the first month of life, followed by a continuous decline with age.Conclusion
Our results corroborate those of previous studies showing that thyroid hormone levels change markedly during childhood, and that adult reference intervals are not universally applicable to children. Moreover, differences of our reference intervals compared to previous studies were observed, likely caused by different antibody characteristics of various analytical methods, different populations or undefined geographic covariates, e.g. iodine and selenium status. 相似文献4.
Interactive effects of selenium and antimony on the uptake of selenium, antimony and essential elements in paddy-rice 总被引:2,自引:0,他引:2
Aims
Selenium (Se) can be used to detoxify antimony (Sb); however, the associated mechanisms are not fully understood, in particular, the responses of essential elements to co-exposure to Se and Sb.Methods
To resolve the above question, two nested hydroponic experiments based on a two-factor, five-level central composite design, were performed using a conventional indica rice (Fengmeizhan).Results
The results showed that when the Se concentration was fixed at 0.8 mg L-1, the addition of Sb, even at concentrations as low as 2.171 mg L-1, could produce damages to this plant and significantly reduce both the aboveground and root biomasses, suggesting a high toxicity of Sb to this plant. However, when the Sb concentration was fixed at 5 mg L-1, Se eliminated the negative effects of Sb on the aboveground growth of paddy-rice but did not noticeably affect the root biomass, suggesting a beneficial role of Se in conferring resistance to Sb toxicity in paddy-rice. Interestingly, when the Se concentration was fixed at 0.8 mg L-1, the addition of Sb caused a consistent decrease in the Se concentration in the roots but a slight increase in the Se concentration in the aboveground, suggesting a dual effect of Sb on Se uptake. Furthermore, the addition of Sb could counterbalance the negative effects of 0.8 mg L-1 Se on the uptake of most of the tested essential elements, significantly increased their concentrations in the different tissues of this plant.Conclusions
The Se-mediated alleviation of Sb toxicity could be closely connected with (1) the direct inhibition of Sb uptake; and (2) the uptake regulation of some essential elements, such as calcium (Ca), magnesium (Mg) and potassium (K). This study contributes to the understanding of both the the interactions between Se and Sb and their effects on the uptake of essential elements in paddy-rice. 相似文献5.
Michael Sand Marcos Gelos Daniel Sand Falk G Bechara Gerd Bonhag Ellen Welsing Benno Mann 《World journal of surgical oncology》2006,4(1):1-4
Background
Epithelial ovarian neoplasms are an important cause of morbidity and mortality in women. The surgical management of ovarian neoplasms depends on their correct categorization as benign, borderline or malignant. This study was undertaken to evaluate the accuracy of intra-operative frozen section in the diagnosis of various categories of ovarian neoplasms.Methods
Intraoperative frozen section diagnosis was retrospectively evaluated in 217 patients with suspected ovarian neoplasms who underwent surgery as primary line of therapy at our institution. This was compared with the final histopathologic diagnosis on paraffin sections.Results
In 7 patients (3.2%) no opinion on frozen section was possible. In the remaining 210 patients frozen section report had a sensitivity of 100%, 93.5% and 45.5% for benign, malignant and borderline tumors. The corresponding specificities were 93.2%, 98.3% and 98.5% respectively. The overall accuracy of frozen section diagnosis was 91.2%. The majority of cases of disagreement were in the mucinous and borderline tumors.Conclusion
Intraoperative frozen section has high accuracy in the diagnosis of suspected ovarian neoplasms. It is a valuable tool to guide the surgical management of these patients and should be routinely used in all major oncology centers. 相似文献6.
The effect of transpiration on selenium uptake and mobility in durum wheat and spring canola 总被引:6,自引:0,他引:6
Heidi Renkema Amy Koopmans Leanne Kersbergen Julie Kikkert Beverley Hale Edward Berkelaar 《Plant and Soil》2012,354(1-2):239-250
Aims
The objective of this study was to determine the relative importance of transpirational pull, Se speciation, sulfate and species on Se accumulation by plants, in order to determine which of these factors must be considered in the future development of models to predict Se accumulation by plants.Methods
Seedlings of durum wheat (Triticum turgidum L. var durum cv ‘Kyle’) and spring canola (Brassica napus L. var Hyola 401) were grown hydroponically and exposed to SeO 4 2- (selenate) with or without SO 4 2- (sulfate), or to HSeO 3 - (biselenite) under different transpiration regimes altered through ‘low’ (~50%) or ‘high’ (~78%) relative humidity (RH). Plants were harvested after 0, 8, 16, or 24?h exposures, digested, and analyzed for Se by GFAAS.Results
Accumulation and distribution of Se by plants is dependent on plant species, Se speciation in the nutrient solution, SO 4 2- competition, and transpiration regimes. Canola accumulated and translocated more Se than wheat. In wheat and canola, the greatest accumulation and translocation of Se occurred when plants were exposed to SeO 4 2- without SO 4 2- compared to solutions of SeO 4 2- with SO 4 2- or HSeO 3 2- . Wheat plants exposed to SeO 4 2- and SO 4 2- had an increased Se accumulation and translocation under increased transpiration rates than when exposed to SeO 4 2- without SO 4 2- or HSeO 3 2- . On the other hand, increases in transpiration increased the translocation of Se to canola shoots when exposed to HSeO 3 - more than any other treatments.Conclusions
Overall, our results suggest that plant species is the most important factor influencing Se accumulation and translocation, but that these endpoints can be modified by climate and specific soil Se or S content. Models to predict accumulation of Se by plants must consider all of these factors to accurately calculate the mechanisms of uptake and translocation. 相似文献7.
8.
J Bojunga N Dauth C Berner G Meyer K Holzer L Voelkl E Herrmann H Schroeter S Zeuzem M Friedrich-Rust 《PloS one》2012,7(8):e42735
Background
Acoustic Radiation Force Impulse (ARFI)-Imaging is an ultrasound-based elastography method enabling quantitative measurement of tissue stiffness. The aim of the present study was to evaluate sensitivity and specificity of ARFI-imaging for differentiation of thyroid nodules and to compare it to the well evaluated qualitative real-time elastography (RTE).Methods
ARFI-imaging involves the mechanical excitation of tissue using acoustic pulses to generate localized displacements resulting in shear-wave propagation which is tracked using correlation-based methods and recorded in m/s. Inclusion criteria were: nodules ≥5 mm, and cytological/histological assessment. All patients received conventional ultrasound, real-time elastography (RTE) and ARFI-imaging.Results
One-hundred-fifty-eight nodules in 138 patients were available for analysis. One-hundred-thirty-seven nodules were benign on cytology/histology, and twenty-one nodules were malignant. The median velocity of ARFI-imaging in the healthy thyroid tissue, as well as in benign and malignant thyroid nodules was 1.76 m/s, 1.90 m/s, and 2.69 m/s, respectively. While no significant difference in median velocity was found between healthy thyroid tissue and benign thyroid nodules, a significant difference was found between malignant thyroid nodules on the one hand and healthy thyroid tissue (p = 0.0019) or benign thyroid nodules (p = 0.0039) on the other hand. No significant difference of diagnostic accuracy for the diagnosis of malignant thyroid nodules was found between RTE and ARFI-imaging (0.74 vs. 0.69, p = 0.54). The combination of RTE with ARFI did not improve diagnostic accuracy.Conclusions
ARFI can be used as an additional tool in the diagnostic work up of thyroid nodules with high negative predictive value and comparable results to RTE. 相似文献9.
Anna Grandone Nicola Santoro Filomena Coppola Paolo Calabrò Laura Perrone Miraglia Emanuele del Giudice 《BMC endocrine disorders》2010,10(1):1-7
Background
In recent years, there has been an increasing attention to thyroid function in paediatric obese patients. In the present study we aimed 1) to determine the prevalence of abnormally elevated thyroid-stimulating hormone (TSH) levels in Italian obese children and adolescents 2) to investigate whether hyperthyrotropinemia in obese children cardiovascular and metabolic risk factors 3) to verify if TSH elevation is reversible after weight loss.Methods
We examined 938 obese children and adolescents (450 females). Anthropometric, metabolic and hormonal variables were determined at baseline and, in a subgroup of children with hyperthyrotropinemia, after a six month weight loss program.Results
Hyperthyrotropinemia (TSH ≥4.2 μUI/ml) was diagnosed in 120 patients (12,8%). Body mass index (BMI) z-score (p = 0.02) and free T3 (fT3) levels (p = 0.03) were higher in patients with elevated TSH compared to the group with normal TSH. There were not significant differences in other metabolic parameters between the two groups. A positive correlation between baseline TSH and BMI z-score (p = 0.0045) and between Ft3 and BMI z-score (p = 0.0034) was observed, while there was no correlation between TSH and lipids. Twenty-three patients among those with hyperthyrotropinemia who participated to weight reduction intervention (64 patients), presented substantial weight loss and concomitantly a significant decrease in TSH and in fT3.Conclusions
These results suggest that: (1) a moderate elevation of TSH concentrations, is frequently found in obese children; (2) in obese children increase of TSH is not associated to metabolic risk factors, (3) hyperthyrotropinemia is reversible after weight loss and these data suggest that it should not be treated. 相似文献10.
Atilla Cayir Hakan Doneray Nezahat Kurt Zerrin Orbak Avni Kaya Mehmet Ibrahim Turan Abdulkadir Yildirim 《Biological trace element research》2014,157(2):95-100
Obesity is a multifactorial disease developing following impairment of the energy balance. The endocrine system is known to be affected by the condition. Serum thyroid hormones and trace element levels have been shown to be affected in obese children. Changes in serum thyroid hormones may result from alterations occurring in serum trace element levels. The aim of this study was to evaluate whether or not changes in serum thyroid hormone levels in children with exogenous obesity are associated with changes in trace element levels. Eighty-five children diagnosed with exogenous obesity constituted the study group, and 24 age- and sex-matched healthy children made up the control group. Serum thyroid stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), thyroglobulin (TG), selenium (Se), zinc (Zn), copper (Cu), and manganese (Mn) levels in the study group were measured before and at the third and sixth months of treatment, and once only in the control group. Pretreatment fT4 levels in the study group rose significantly by the sixth month (p?=?0.006). Zn levels in the patient group were significantly low compared to the control group (p?=?0.009). Mn and Se levels in the obese children before and at the third and sixth months of treatment were significantly higher than those of the control group (p?=?0.001, p?=?0.001). In conclusion, fT4, Zn, Cu, Mn, and Se levels are significantly affected in children diagnosed with exogenous obesity. The change in serum fT4 levels is not associated with changes in trace element concentrations. 相似文献
11.
Marjolijn CE Bragt Jogchum Plat Marco Mensink Patrick Schrauwen Ronald P Mensink 《BMC endocrine disorders》2009,9(1):1-9
Background
The aim of this study is to perform a cost-effectiveness comparison between palpation-guided thyroid fine-needle aspiration biopsies (P-FNA) and ultrasound-guided thyroid FNA biopsies (USG-FNA).Methods
Each nodule was considered as a case. Diagnostic steps were history and physical examination, TSH measurement, Tc99m thyroid scintigraphy for nodules with a low TSH level, initial P-FNA versus initial USG-FNA, repeat USG-FNA for nodules with initial inadequate P-FNA or USG-FNA, hemithyroidectomy for inadequate repeat USG-FNA. American Thyroid Association thyroid nodule management guidelines were simulated in estimating the cost of P-FNA strategy. American Association of Clinical Endocrinologists guidelines were simulated for USG-FNA strategy. Total costs were estimated by adding the cost of each diagnostic step to reach a diagnosis for 100 nodules. Strategy cost was found by dividing the total cost to 100. Incremental cost-effectiveness ratio (ICER) was calculated by dividing the difference between strategy cost of USG-FNA and P-FNA to the difference between accuracy of USG-FNA and P-FNA. A positive ICER indicates more and a negative ICER indicates less expense to achieve one more additional accurate diagnosis of thyroid cancer for USG-FNA.Results
Seventy-eight P-FNAs and 190 USG-FNAs were performed between April 2003 and May 2008. There were no differences in age, gender, thyroid function, frequency of multinodular goiter, nodule location and diameter (median nodule diameter: 18.4 mm in P-FNA and 17.0 mm in USG-FNA) between groups. Cytology results in P-FNA versus USG-FNA groups were as follows: benign 49% versus 62% (p = 0.04), inadequate 42% versus 29% (p = 0.03), malignant 3% (p = 1.00) and indeterminate 6% (p = 0.78) for both. Eleven nodules from P-FNA and 18 from USG-FNA group underwent surgery. The accuracy of P-FNA was 0.64 and USG-FNA 0.72. Unit cost of P-FNA was 148 Euros and USG-FNA 226 Euros. The cost of P-FNA strategy was 534 Euros and USG-FNA strategy 523 Euros. Strategy cost includes the expense of repeat USG-FNA for initial inadequate FNAs and surgery for repeat inadequate USG-FNAs. ICER was -138 Euros.Conclusion
Universal application of USG-FNA for all thyroid nodules is cost-effective and saves 138 Euros per additional accurate diagnosis of benign versus malignant thyroid nodular disease.Trial registration
ClinicalTrials.gov, NCT00571090 相似文献12.
Background
Interferon-α in combination with ribavirin is the current gold standard for treatment of chronic hepatitis C. It is unknown if the development of autoimmune thyroid disease (TD) during treatment confers an improved chance of achieving sustained virologic response. The aim of this study is to assess the chance of achieving sustained virologic response (SVR) in patients who developed TD during treatment when compared with those who did not.Methods
We performed a tertiary hospital-based retrospective nested case-control analysis of 19 patients treated for hepatitis C who developed thyroid disease, and 76 controls (matched for age, weight, gender, cirrhosis and aminotransferase levels) who did not develop TD during treatment. Multivariate logistic-regression models were used to compare cases and controls.Results
The development of TD was associated with a high likelihood of achieving SVR (odds ratio, 6.0; 95% confidence interval, 1.5 to 24.6) for the pooled group containing all genotypes. The likelihood of achieving SVR was increased in individuals with genotype 1 HCV infection who developed TD (odds ratio, 5.2; 95% confidence interval, 1.2 to 22.3), and all genotype 3 patients who developed TD achieved SVR.Conclusions
Development of TD during treatment for hepatitis C infection is associated with a significantly increased chance of achieving SVR. The pathophysiogical mechanisms for this observation remain to be determined.Trial Registration
The Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRB12610000830099 相似文献13.
14.
Eleftheria Stavridou Scott D. Young Kristian Thorup-Kristensen 《Plant and Soil》2012,351(1-2):149-160
Background and Aims
Selenium (Se) is an essential nutrient for humans and animals. In order to ensure an optimal concentration of Se in crops, Se fertilisers are applied. Catch crops may be an alternative way to increase Se concentrations in vegetables.Methods
Three experiments in Denmark between 2007–10 investigated the ability of catch crops (Italian ryegrass, fodder radish and hairy vetch) under different fertiliser regimes to reduce soil Se content in the autumn and to increase its availability in spring to the succeeding crop.Results and Conclusions
The catch crops (Italian ryegrass and fodder radish) increased water-extractable Se content in the 0.25–0.75?m soil layer in only one of the experiments. Selenium uptake by the catch crops varied between 65 and 3263?mg?ha?1, depending on species, year and fertilisation treatment; this corresponded to 0.1–3.0% of the water-extractable soil Se content. The influence of catch crops on Se concentrations and uptake in onions and cabbage was low. There was a decrease in Se uptake and recovery of applied Se by onions following catch crops, which might indicate Se immobilisation during catch crop decomposition. 相似文献15.
Zhinan Ding Jingzhang Ji Guorong Chen Hezhi Fang Shihui Yan Lijun Shen Jia Wei Kaiyan Yang Jianxin Lu Yidong Bai 《Biochimica et Biophysica Acta (BBA)/General Subjects》2010
Background
Mitochondrial defects have been associated with various human conditions including cancers.Methods
We analyzed the mutations at the mitochondrial DNA (mtDNA) in patients with different thyroid lesions. In particular, in order to investigate if the accumulation of mtDNA mutations play a role in tumor progression, we studied the highly variable main control region of mtDNA, the displacement-loop (D-loop) in patients with non-tumor nodular goiters, with benign thyroid adenomas, and with malignant thyroid carcinomas. Total thyroid tumor or goiter samples were obtained from 101 patients, matched with nearby normal tissue and blood from the same subject.Results
Noticeably, mitochondrial microsatellite instability (mtMSI) was detected in 2 of 19 nodular goiters (10.53%), and 8 of 77 (10.39%) malignant thyroid carcinomas. In addition, 6 patients, including 5 (6.49%) with malignant thyroid carcinomas and 1 (5.26%) with nodular goiter, were found to harbor point mutations. The majority of the mutations detected were heteroplasmic.General significance
Our results indicate that mtDNA alterations in the D-loop region could happen before tumorigenesis in thyroid, and they might also accumulate during tumorigenesis. 相似文献16.
Pre‐operative features of non‐invasive follicular thyroid neoplasms with papillary‐like nuclear features: An analysis of their cytological,Gene Expression Classifier and sonographic findings
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Objective
To investigate the corresponding cytological diagnoses, Gene Expression Classifier (GEC) results and ultrasound features of thyroid nodules diagnosed as non‐invasive follicular thyroid neoplasms with papillary‐like nuclear features (NIFTP), as well as any coexisting pathology.Methods
We performed a retrospective review of thyroid nodules histologically diagnosed as NIFTP at our institution between 1st April 2016 and 1st April 2017. The following data points were collected: demographics, nodule size, ultrasound features, cytological diagnosis, GEC results, origin of sample (in‐house vs outside hospital) and any additional pathology identified in the resection specimen.Results
The case cohort included 87 nodules diagnosed as NIFTP (size range: 1‐7 cm, mean: 2.5 cm) from 82 patients (age range: 22‐82, mean age: 50.4, M:F—1:4.1). Corresponding FNA results were available for 72 nodules (82.8%) and were categorised as follows: benign (n = 5, 6.9%), atypia of unknown significance/follicular lesion of undetermined significance (n = 29, 40.3%), follicular neoplasm/suspicious for follicular neoplasm/follicular neoplasm with oncocytic features (n = 27, 37.5%), suspicious for papillary thyroid carcinoma (n = 6, 8.3%) and malignant (n = 5, 6.9%). GEC results were available for 32 (44.4%) nodules, with the majority of cases classified as suspicious (81.3%). On ultrasound, most of the nodules were predominantly solid (81.8%), vascular (93.8%), non‐calcified (86.5%), and either hypoechoic (44.9%) or isoechoic (38.8%). In addition to NIFTP and other benign findings in the background thyroid, 75 separate malignant tumours were identified in 38 (46.3%) patients, many of which were papillary thyroid microcarcinomas (86.5%) with lymph node metastases present in two cases.Conclusions
The majority of thyroid nodules histologically diagnosed as NIFTP have indeterminate cytology (77.8%) and are classified as suspicious (81.3%) by GEC testing. Taken together, these findings can guide clinicians toward a more conservative therapeutic approach.17.
Selenium-rich dissolved organic matter determines selenium uptake in wheat grown on Low-selenium arable land soils 总被引:1,自引:0,他引:1
Aims
The study aimed to find soil parameters that are best related to Se plant uptake for low Se soils with predominantly organic Se, and to explore the mechanisms that control Se bioavailability in the soils under study.Methods
A pot experiment using nineteen soil samples taken from different fields of arable land (potato fields) in the Netherlands was conducted on summer wheat (Triticum aestivum L.). Selenium in wheat shoots and soil parameters, including basic soil properties, C:N ratio, inorganic selenite content, and Se and organic C in different soil extractions (0.01 M CaCl2, 0.43 M HNO3, hot water, ammonium oxalate, aqua regia) were analysed. Regression analysis was performed to identify soil parameters that determine Se content in wheat shoots.Results
The regression model shows that Se:DOC ratio in 0.01 M CaCl2 soil extraction explained about 88 % of the variability of Se uptake in wheat shoots. Selenium uptake increased with Se:DOC ratio in CaCl2 extraction, which can be interpreted as a measure of the content of soluble Se-rich organic molecules. Selenium:DOC ratio in CaCl2 extraction and Se uptake increased towards higher soil pH and lower soil C:N ratio. The soil C:N ratio is also negatively correlated to Se:organic C ratio in other extractions (0.43 M HNO3, hot water, ammonium oxalate, aqua regia), indicating that at low soil C:N ratio soil organic matter is richer in Se. Contrarily, the soil pH is positively and strongly correlated to Se:organic C ratio in CaCl2 and hot water extractions, but only weakly correlated to Se:organic C ratio in other extractions.Conclusions
Selenium-rich dissolved organic matter is the source of bioavailable Se in low Se soils with predominantly organic Se. The soil pH and quality of soil organic matter (i.e. soil C:N ratio) are the main soil properties determining Se bioavailability in these soil types.18.
Rui M. Rua Mª. Luisa Ojeda Fátima Nogales Jose Maria Rubio Manuel Romero-Gómez Jorge Funuyet Mª. Luisa Murillo Olimpia Carreras 《Life sciences》2014
Aims
Antioxidant system abnormalities have been associated with ethanol consumption. This study examines the effects of chronic ethanol consumption on oxidative balance, including selenium (Se) levels in alcoholic patients with or without liver disease, and if these measurements could be indicative of liver disease.Main methods
Serum Se levels, antioxidant enzymes' activities, malondialdehyde (MDA) and protein carbonyl (PC) were determined in three groups of patients: alcoholics without liver disease, alcoholics with liver disease, and non-alcoholics with liver disease; and in healthy volunteers.Key findings
Serum Se levels were lower in alcoholic patients and in patients affected by liver disease and especially lower in the alcoholic liver disease group. These values were correlated with the activity of glutathione peroxidase (GPx), the antioxidant selenoprotein. The antioxidant activities of the glutathione reductase (GR) and superoxide dismutase (SOD) were also lower in the three non-healthy groups. However, GR activity decreased and SOD activity increased in the non-alcoholic liver disease group versus alcoholic groups. Higher concentrations of PC in serum were found in non-healthy groups and were higher in alcoholic patients who also showed higher MDA levels. The highest MDA and PC levels were found in the alcoholic liver disease group.Significance
We conclude that serum Se levels are drastically decreased in alcoholic liver disease patients, showing that this element has a direct correlation with GPx activity, and lipid oxidation, suggesting that the serum Se/MDA ratio could be an indicator of hepatic damage caused by alcohol consumption, and pointing to Se as a possible antioxidant therapy. 相似文献19.
Xiaofang Deng Zhuqing Zhao JiaJie Zhou JinZhao Chen Chenhao Lv Xinwei Liu 《Plant and Soil》2018,433(1-2):55-64
Aims
The objectives of this study were to determine the valence state of Se and major components in Se ore powder, examine its effect on Se enrichment in crops under different cultivation patterns, and assess the safety of edible parts of crops.Methods
Se ore powder from Enshi was subjected to compositional analysis by X-ray photoelectron spectroscopy and applied to rice (wetland) and soybean (dryland) fields before planting.Results
Se was mainly present in tetravalent and zero-valent forms at a 4:6 ratio in Se ore powder. Following soil application of Se ore powder, concentrations of As, Hg, Cr, and Pb in brown rice and soybean seed were below the limit of detection, and the Cd concentration was below the European Union food regulation limit. Organic Se accounted for more than 96% of total Se in both crops, including >91% Se-methionine. Compared with dryland, the flooded environment facilitated residual Se transformation into Fe/Mn oxide-bound Se, and thus increased the potential activity of Se in the soil.Conclusions
Se ore powder can be applied for the production of Se-rich agricultural products in the short-term, and possibilities of upgrading the Se ore product should be considered in the future.20.
Vinod B Shidham Richard Komorowski Marcelle Neuberg Alonzo Walker Bruce H Campbell Chung-Che Chang William W Dzwierzynski 《Diagnostic pathology》2006,1(1):1-9