Mechanistic insight into the interactions of EDDS with copper in the rhizosphere of polluted soils.

The biodegradable S,S-ethylenediaminedisuccinic acid (EDDS) is a promising chelant for chelant-assisted phytoextraction of trace metals in polluted soil. The interactions between EDDS and trace metals/major elements in the soil affect the metal bioavailability and their subsequent phytoextraction efficiency. This study aimed to investigate the macroscopic and molecular-level interactions of EDDS with Cu in the rhizosphere and non-rhizosphere of a Cu-polluted agricultural soil. A multi-interlayer rhizobox planted with ryegrass was used to simulate the transport of EDDS and Cu from the non-rhizosphere to rhizosphere soils. The results showed that EDDS (5 mM kg-1) significantly dissociated Cu (285-690 fold), Fe (by 3.47-60.2 fold), and Al (2.43-5.31 fold) from the soil in comparison with a control group. A combination of micro-X-ray fluorescence, X-ray absorption near-edge structure spectroscopy, and sequential extraction analysis revealed that EDDS primarily chelated the adsorbed fraction of Cu by facilitating the dissolution of goethite. Moreover, as facilitated by ryegrass transpiration, CuEDDS was moved from the non-rhizosphere to rhizosphere and accumulated in ryegrass. In situ processes of Cu extraction and transport by EDDS in the rhizosphere were further elucidated with chemical speciation analysis and geochemical modeling methods.

Transcriptome analysis revealed pivotal transporters involved in the reduction of cadmium accumulation in pak choi (Brassica chinensis L.) by exogenous hydrogen-rich water.

Hydrogen-rich water (HRW) has been widely used in research on plant resistance to Cd. However, the underlying molecular mechanism of HRW in ameliorating cadmium stress in vegetables is largely unknown. In this study, the RNA-sequencing analyses were used to characterize the role of HRW in the alleviation of Cd toxicity in Chinese cabbage seedlings. Based on the obtained results, two genes encoding metal ionic transporters, BcIRT1 and BcZIP2 were ultimately selected out. Then, a systematic validation of the metal ion transport function of these two ZIP-encoding genes of pak choi were performed via a yeast transformation system. The results showed that BcIRT1 and BcZIP2 increased the sensitivity of different yeast mutant strains to relative metal ionic stresses and facilitated the accumulation of metal ions (Cd2+, Mn2+, Zn2+, and Fe2+) in yeast; thus, it suggests that BcIRT1 and BcZIP2 probably have the ability to transport Cd2+, Mn2+, Zn2+ and Fe2+ in pak choi. The time-course and concentration-dependent expression profiles of BcIRT1 and BcZIP2 showed that as time with HRW increased, the effectiveness of the repression on the expression of BcIRT1 and BcZIP2 increased, and as the seedlings were exposed to increased Cd concentrations, the inhibition of BcIRT1 and BcZIP2 by HRW was also increased. Over all, these findings provide new insights into the genome-wide transcriptome profiles in pak choi and show that HRW reduced Cd uptake probably through inhibiting the expression of transporters related to Cd absorption, BcIRT1 and BcZIP2.

Presence of pink-color sign within 1 min after iodine staining has high diagnostic accordance rate for esophageal high-grade intraepithelial neoplasia/invasive cancer.

BACKGROUND/AIM: The dramatic color change after iodine staining (from white-yellow to pink after 2-3 min), designated as the "pink-color sign" (PCS), is indicative of esophageal high-grade intraepithelial neoplasia (HGIN) or an invasive lesion. However, no study has yet examined the association between the time of PCS appearance and histopathology. We investigated the association between the time of PCS appearance and esophageal histopathology in 456 lesions of 438 patients who were examined for suspected esophageal cancer. MATERIALS AND METHODS:: The records of 495 consecutive patients who had suspected esophageal cancer based on gastroscopy and who underwent Lugol's chromoendoscopy from January 2015 to March 2018 were retrospectively reviewed. The time of PCS appearance was recorded in all patients, and tissue specimens were examined. RESULTS: We examined 456 lesions in 438 patients. Use of PCS positivity at 2 min for the diagnosis of HGIN/invasive cancer had a sensitivity of 84.1%, a specificity of 72.7%, and an accuracy of 80.4%. We classified the PCS-positive patients in whom the time of PCS appearance was recorded (168 lesions) into 4 groups: 0-30, 31-60, 61-90, and 91-120 s. Based on a 60-s time for appearance of the PCS, the area under the receiver operating characteristic curve was 0.897, indicating good validity. At the optimal cutoff value of 60 s, the sensitivity was 90.2% and the specificity was 82.3%. The appearance of the PCS within 60 s had a diagnostic accordance rate of 88.6%, significantly higher than appearance of the PCS within 2 min (79.7%, P < 0.05). CONCLUSION: Appearance of the PCS within 1 min after iodine staining has a higher diagnostic accordance rate for esophageal HGIN/invasive cancer than appearance of the PCS at 2 min.

[Extraction of Cd by ramie from soils as affected by applications of chelators and peat].

Pot experiments were performed to study the effectiveness of chelators (EDTA, citric acid) and peat in enhancing phyremediation of heavy metal Cd by ramie. The results showed that peat increased the ramie's biomass by improving soil's physical and chemical properties, and the relative yields of peat alone, chelators(EDTA, citric acid) combined with peat were 1.23, 1.13 and 1.41 respectively. So the combination of citric acid and peat was more useful for growth of the ramie. As far as improving Cd uptake was concerned, it seemed that the combination of chelators with peat significantly promoted Cd uptake by the plant, and the percent of changeable Cd in soil were 61.6% and 58.3% . In addition, it had better bioaccumulation effects to combine with chelators and peat, of which Cd bioaccumulation coefficients were 1.33 and 1.32, compared to 1.11, 1.11 and 1.05 in application of peat, EDTA and citric acid respectively. What's more, cadmium removal rates in soil were up to 1.13% and 1.22% respectively in applications of two kinds of chleators (EDTA, citric acid) combined with peat. Therefore, it had better effects of phytoremediation to accumulate more cadmium amounts by combining with citric acid and peat because of more biomass. In conclusion, the phytoremediation by ramie can be more effective when chelators and peat were combined and added to soils.

Measurement error correction for nutritional exposures with correlated measurement error: use of the method of triads in a longitudinal setting.

Nutritional exposures are often measured with considerable error in commonly used surrogate instruments such as the food frequency questionnaire (FFQ) (denoted by Q(i) for the ith subject). The error can be both systematic and random. The diet record (DR) denoted by R(i) for the ith subject is considered an alloyed gold standard. However, some authors have reported both systematic and random errors with this instrument as well.One goal in measurement error research is to estimate the regression coefficient of T(i) (true intake for the ith subject) on Q(i) denoted by lambda(TQ). If the systematic errors in Q(i) and R(i) (denoted by q(i) and r(i)) are uncorrelated, then one can obtain an unbiased estimate of lambda(TQ) by lambda(RQ) obtained by regressing R(i) on Q(i). However, if Corr(q(i), r(i))>0, then lambda(RQ)>lambda(TQ).In this paper, we propose a method for indirectly estimating lambda(TQ) even in the presence of correlated systematic error based on a longitudinal design where Q(i) (surrogate measure of dietary intake), R(i) (a reference measure of dietary intake), and M(i) (a biomarker) are available on the same subjects at 2 time points. In addition, between-person variation in mean levels of M(i) among people with the same dietary intake is also accounted for. The methodology is illustrated for dietary vitamin C intake based on longitudinal data from 323 subjects in the European Prospective Investigation of Cancer (EPIC)-Norfolk study who provided two measures of dietary vitamin C intake from the FFQ (Q(i)) and a 7-day DR (R(i)) and plasma vitamin C (M(i)) 4 years apart.

Heat stress increases the efficiency of EDTA in phytoextraction of heavy metals.

Solution culture and pot experiments were carried out to investigate the effects of root damage on phytoextraction of heavy metals. In hydroponics, roots of corn (Zea mays L.) seedlings were pretreated with heating stress, and then were exposed to 250 microM Pb+250 microM EDTA solutions for 7d. The results showed that the preheating treatment significantly increased Pb transportation from roots to shoots. In pot experiments, the effect of hot EDTA solution (95 degrees C) on the accumulation of heavy metal in the shoot of corn and pea (Pisum sativum L.) was also examined. Compared to normal EDTA (25 degrees C) treatment, application of hot EDTA solution to the soil surface increased the total removal of Pb in shoots of corn and pea by about 8- and 12-fold, respectively, in an artificially multimetal-contaminated soil. In addition, hot EDTA solution increased the shoot Cu removal by about 6-fold for corn and 9-fold for pea, respectively, in a naturally Cu-contaminated soil. These results suggested that exposure of roots to high temperature could increase the efficiency of EDTA on the accumulation of heavy metals in shoots. This new approach can help to minimize the amount of chelate applied in the field and reduce the potential risk of heavy metals' leaching.

Breast carcinoma screening and risk perception among women at increased risk for breast carcinoma: results from a national survey.

BACKGROUND: The Gail model is validated to estimate breast carcinoma risk. The authors assessed the association of Gail risk scores with screening and cancer risk perception. METHODS: Using the 2000 National Health Interview Survey, the authors studied women ages 41-70 without a cancer history. Gail scores > or = 1.66% defined increased risk. The authors used logistic regression to assess associations between breast carcinoma risk and previous and recent (< or = 1 year) mammography and clinical breast examination (CBE). RESULTS: Of 6410 women, 15.7% had increased risk. High-risk women more frequently reported previous mammograms (94% vs. 85%; P < 0.0001), previous CBE (93% vs. 88%; P < 0.0001), recent mammograms (70% vs. 54%; P < 0.0001), recent CBE (71% vs. 61%; P < 0.0001), and high cancer risk perception (20% vs. 9%; P < 0.0001). However, 30% of high-risk women had not received a recent mammogram. After adjustment for sociodemographic factors, access to care factors, and cancer risk perception, high-risk women remained more likely to have received recent mammography (adjusted odds ratio [OR], 1.45, 95% confidence interval [95% CI], 1.19-1.77), recent CBE (OR, 1.32; 95% CI, 1.08-1.61]), and previous mammography than average-risk women. The authors observed an interaction between risk and age, with women ages 41-49 years more frequently reporting previous mammography (OR, 4.79; 95% CI, 1.55-4.81) than average-risk, same-age women. For women age > or = 50 years, the odds of previous mammography were similar regardless of risk. CONCLUSIONS: In a nationally representative sample, 15.7% of women had increased breast carcinoma risk using the Gail model. High-risk women perceived higher cancer risk and more often received screening. However, nearly one in three high-risk women did not receive recent screening and most of these women did not perceive increased risk.

Separate Expression and Characterization of the Heavy- and the Light-chain of A HBsAg Specific Murine-human Chimeric Antibody in Insect Cells.

Both the heavy- and light-chain of a murine-human chimeric antibody with specificity for hepatitis B virus surface antigen have been expressed separately in a baculovirus expression system. The heavy- and light-chain variable region (VH and VL) genes encoding the marine-monoclonal antibody OH3 were combined with human gamma3 and kappa constant region genes to construct the murine-human chimeric genes, respectively. The transfer vectors containing the chimeric genes were cotransfected into Sf9 cells with linearized virus DNA and recombinant viruses were isolated by dot hybridization, PCR and Southern blot analysis. The chimeric heavy- and light-chain was expressed respectively in the recombinant viruses-infected insect cells and the characterization by Western blot and competitive ELISA demonstrated that both of the expressed chimeric heavy- and light-chain have the specificity of HBsAg binding.

The Cloning and Construction of a Murine-human Chimeric Antibody with Specificity for HBsAg and the Expression of the Chimeric Heavy Chain in E. coli.

The genes encoding the heavy and light chain variable regions (V(H) and V(K)) of the murine monoclonal antibody with the specificity for hepatitis B virus surface antigen (HBsAg) have been clone by using RT-PCR. They were combined to the Human C(gamma)(3) and C(K) genes respectively to construct the murine human chimeric antibody genes The chimeric heavy chain was expressed in E. coli, and characterized by SDS-PAGE, Western-blot, indirect ELISA Assay to demonstrate the expression product has the HBsAg-binding ability.