bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of cadmium ion uptake in rice (Oryza sativa) cells by a wall‐bound form of silicon
Authors: Liu Jian , Ma Jie , He Congwu , Li Xiuli , Zhang Wenjun , Xu Fangsen , Lin Yongjun , Wang Lijun 
Published: October 2013

Summary

The stresses acting on plants that are alleviated by silicon (Si) range from biotic to abiotic stresses, such as heavy metal toxicity. However, the mechanism of stress alleviation by Si at the single‐cell level is poorly understood.

We cultivated suspended rice (Oryza sativa) cells and protoplasts and investigated them using a combination of plant nutritional and physical techniques including inductively coupled plasma mass spectrometry (ICP‐MS), the scanning ion‐selective electrode technique (SIET) and X‐ray photoelectron spectroscopy (XPS).

We found that most Si accumulated in the cell walls in a wall‐bound organosilicon compound. Total cadmium (Cd) concentrations in protoplasts from Si‐accumulating (+Si) cells were significantly reduced at moderate concentrations of Cd in the culture medium compared with those from Si‐limiting (−Si) cells. In situ measurement of cellular fluxes of the cadmium ion (Cd2+) in suspension cells and root cells of rice exposed to Cd2+ and/or Si treatments showed that +Si cells significantly inhibited the net Cd2+ influx, compared with that in −Si cells. Furthermore, a net negative charge (charge density) within the +Si cell walls could be neutralized by an increase in the Cd2+ concentration in the measuring solution.

A mechanism of co‐deposition of Si and Cd in the cell walls via a [Si‐wall matrix]Cd co‐complexation may explain the inhibition of Cd ion uptake, and may offer a plausible explanation for the in vivo detoxification of Cd in rice.
The Arabidopsis RAD51 paralogs RAD51B,RAD51D and XRCC2 play partially redundant roles in somatic DNA repair and gene regulation
Authors: Wang Yingxiang , Xiao Rong , Wang Haifeng , Cheng Zhihao , Li Wuxing , Zhu Genfeng , Wang Ying , Ma Hong 
Published: October 2013

Summary

The eukaryotic RAD51 gene family has seven ancient paralogs conserved between plants and animals. Among these, RAD51, DMC1, RAD51C and XRCC3 are important for homologous recombination and/or DNA repair, whereas single mutants in RAD51B, RAD51D or XRCC2 show normal meiosis, and the lineages they represent diverged from each other evolutionarily later than the other four paralogs, suggesting possible functional redundancy.

The function of Arabidopsis RAD51B, RAD51D and XRCC2 genes in mitotic DNA repair and meiosis was analyzed using molecular genetic, cytological and transcriptomic approaches.

The relevant double and triple mutants displayed normal vegetative and reproductive growth. However, the triple mutant showed greater sensitivity than single or double mutants to DNA damage by bleomycin. RNA‐Seq transcriptome analysis supported the idea that the triple mutant showed DNA damage similar to that caused by bleomycin. On bleomycin treatment, many genes were altered in the wild‐type but not in the triple mutant, suggesting that the RAD51 paralogs have roles in the regulation of gene transcription, providing an explanation for the hypersensitive phenotype of the triple mutant to bleomycin.

Our results provide strong evidence that Arabidopsis XRCC2, RAD51B and RAD51D have complex functions in somatic DNA repair and gene regulation, arguing for further studies of these ancient genes that have been maintained in both plants and animals during their long evolutionary history.
Leptin levels and risk of type 2 diabetes: gender‐specific meta‐analysis
Authors: Chen G.‐C. , Qin L.‐Q. , Ye J.‐K. 
Published: October 2013

SummaryThis meta‐analysis aimed to assess the gender‐specific differences in the relationship between circulating leptin levels and risk of type 2 diabetes. Published prospective studies that reported the association of leptin levels with risk of type 2 diabetes for a certain gender or those that reported gender‐specific associations were considered. Dose‐response relationships were assessed by the generalized least squares trend estimation and summary relative risks (RRs) with 95% confidence interval (CI) were computed with the random‐effects model. Stratified and sensitivity analyses were also performed to investigate potential sources of heterogeneity. Overall, 11 prospective studies were identified. The summary RR for an increment in leptin levels of 1‐log ng mL−1 was 1.37 (95% CI, 1.13–1.66) for men and 0.96 (95% CI, 0.90–1.03) for women. The differences between genders were statistically significant (P for interaction = 0.006). Subgroup and sensitivity analyses generally confirmed the robustness of these findings. Furthermore, the increased risk in men appeared non‐linear, with a tendency to plateau at high levels (P for non‐linearity = 0.03). Little evidence of publication bias was found. Collectively, higher leptin levels were found to be associated with elevated risk of type 2 diabetes in men but not in women.
Variations of pupil centration and their effects on video eye tracking
Authors: Wildenmann Ulrich , Schaeffel Frank 
Published: October 2013

AbstractPurposeTo evaluate measurement errors that are introduced in video eye tracking when pupil centration changes with pupil size.MethodsSoftware was developed under Visual C++ to track both pupil centre and corneal centre at 87 Hz sampling rate at baseline pupil sizes of 4.75 mm (800 lux room illuminance) and while pupil constrictions were elicited by a flashlight. Corneal centres were determined by a circle fit through the pixels detected at the corneal margin by an edge detection algorithm. Standard deviations for repeated measurements were ±0.04 mm for horizontal pupil centre position and ±0.04 mm for horizontal corneal centre positions and ±0.03 mm for vertical pupil centre position and ±0.05 mm for vertical corneal centre position. Ten subjects were tested (five female, five male, age 25–58 years).ResultsAt 4 mm pupil sizes, the pupils were nasally decentred relative to the corneal centre by 0.18 ± 0.19 mm in the right eyes and −0.14 ± 0.22 mm in the left eyes. Vertical decentrations were 0.30 ± 0.30 mm and 0.27 ± 0.29 mm, respectively, always in a superior direction. At baseline pupil sizes (the natural pupil sizes at 800 lux) of 4.75 ± 0.52 mm, the decentrations became less (right and left eyes: horizontal 0.17 ± 0.20 mm and −0.12 ± 0.22 mm, and vertical 0.26 ± 0.28 mm and 0.20 ± 0.25 mm). While pupil decentration changed minimally in eight of the subjects, it shifted considerably in two others. Averaged over all subjects, the shift of the pupil centre position per millimetre pupil constriction was not significant (right and left eyes: −0.03 ± 0.07 mm and 0.03 ± 0.04 mm nasally per mm pupil size change, respectively, and −0.04 ± 0.06 mm and −0.05 ± 0.12 mm superiorly). Direction and magnitude of the changes in pupil centration could not be predicted from the initial decentration at baseline pupil sizes.ConclusionsIn line with data in the literature, the pupil centre was significantly decentred relative to the corneal centre in the nasal and superior direction. Pupil decentration changed significantly with pupil size by 0.05 mm on average for 1 mm of constriction. Assuming a Hirschberg ratio of 12° mm−1, a shift of 0.05 mm is equivalent to a measurement error in a Purkinje image‐based eye tracker of 0.6°. However, the induced measurement error could also exceed 1.5° in some subjects for only a 1 mm change in pupil size.
UVA and UVB‐Induced 8‐Methoxypsoralen Photoadducts and a Novel Method for their Detection by Surface‐Enhanced Laser Desorption Ionization Time‐of‐Flight Mass Spectrometry (SELDI‐TOF MS)
Authors: Buhimschi Alexandru D. , Gasparro Francis P. 
Published: October 2013

AbstractUVA‐activated psoralens are used to treat hyperproliferative skin conditions due to their ability to form DNA photoadducts, which impair cellular processes and may lead to cell death. Although UVA (320–400 nm) is more commonly used clinically, studies have shown that UVB (280–320 nm) activation of psoralen can also be effective. However, there has been no characterization of UVB‐induced adduct formation in DNA alone. As psoralen derivatives have a greater extinction coefficient in the UVB region (11 800 cm−1 M−1 at 300 nm) compared with the UVA region (2016 cm−1 M−1 at 365 nm), a greater extent of adduct formation is expected. SELDI‐TOF, a proteomic technique that combines chromatography with mass spectrometry, was used to detect photoadduct formation in an alternating A–T oligonucleotide. 8‐Methoxypsoralen (8‐MOP) and DNA solutions were irradiated with either UVA or UVB. An adduct peak was obtained with SELDI‐TOF. For UVB‐activated 8‐MOP, the extent of adducts was three times greater than for UVA. HPLC ESI‐MS analysis showed that UVB irradiation yielded high levels of 3,4‐monoadducts (78% of total adducts). UVA was more effective than UVB at conversion of 4′,5′‐monoadducts to crosslinks (17% vs 4%, respectively). This report presents a method for comparing DNA binding efficiencies of interstrand crosslink inducing agents.
Neutrophils have a protective role during early stages of Leishmania amazonensis infection in BALB/c mice
Authors: Sousa L. M. A. , Carneiro M. B. H. , Resende M. E. , Martins L. S. , dos Santos L. M. , Vaz L. G. , Mello P. S. , Mosser D. M. , Oliveira M. A. P. , Vieira L. Q. 
Published: October 2013

SummaryNeutrophils are involved in the early stages of immune responses to pathogens. Here, we investigated the role of neutrophils during the establishment of Leishmania amazonensis infection in BALB/c and C57BL/6 mice. First, we showed an accumulation of neutrophils between 6 and 24 h post‐infection, followed by a reduction in neutrophil numbers after 72 h. Next, we depleted neutrophils prior to infection using RB6‐8C5 or 1A8 mAb. Neutrophil depletion led to faster lesion development, increased parasite numbers and higher arginase activity during the first week of infection in BALB/c mice, but not in C57BL/6 mice. Increased susceptibility was accompanied by augmented levels of anti‐L. amazonensis IgG and increased production of IL‐10 and IL‐17. Because IL‐10 is a mediator of susceptibility to Leishmania infection, we blocked IL‐10 signalling in neutrophil‐depleted mice using anti‐IL‐10R. Interestingly, inhibition of IL‐10 signalling abrogated the increase in parasite loads observed in neutrophil‐depleted mice, suggesting that parasite proliferation is at least partially mediated by IL‐10. Additionally, we tested the effect of IL‐17 in inflammatory macrophages and observed that IL‐17 increased arginase activity and favoured parasite growth. Taken together, our data indicate that neutrophils control parasite numbers and limit lesion development during the first week of infection in BALB/c mice.
Maternal Liver Damage Delays Meiotic Resumption in Bovine Oocytes through Impairment of Signalling Cascades Originated from Low p38MAPK Activity in Cumulus Cells
Authors: Tanaka H , Takeo S , Monji Y , Kuwayama T , Iwata H 
Published: October 2013

ContentsThe main objective of the present study is to investigate the molecular mechanism underlying the delay in progression of nuclear maturation in oocytes derived from cows with damaged livers (DL cows), which was previously reported. In present study, delayed progression of nuclear maturation of oocytes derived from DL cows relative to oocytes derived from cows with healthy livers (HL cows) was accompanied by low maturation promoting factor (MPF) activity (0.43 fold, p < 0.05). When cumulus cells were removed from cumulus‐oocyte complexes and the denuded oocytes were cultured, there was no difference in the progression of nuclear maturation between the two liver conditions. In addition, gap junctional communication (GJC) between the oocyte and cumulus cells was higher in DL cows than in HL cows at 3 and 7 h of in vitro maturation (IVM) (p < 0.05). Supplementation of IVM medium with epidermal growth factor (EGF) increased the ratio of germinal vesicle breakdown (GVBD) of oocytes derived from DL cows to the level seen in oocytes derived from HL cows. Additionally, the level of p38MAPK phosphorylation at 0 h of IVM was significantly lower in cumulus cells derived from DL cows than in cumulus cells derived from HL cows (HL cows, 53.5%; DL cows, 28.9%; p < 0.05). Thus, a low level of p38MAPK phosphorylation in cumulus cells induced slow GJC closure between oocyte and cumulus cells, which resulted in slow meiotic maturation of oocytes derived from DL cows.
Low Oxygen Tension and Relative Defined Culture Medium with 3, 4‐Dihydroxyflavone are Beneficial for Yak–Bovine Interspecies Somatic Cell Nuclear Transfer Embryo
Authors: Xiong X , Li J , Wang L , Zhong J , Zi X , Wang Y 
Published: October 2013

ContentsWith an aim to improve the efficiency of yak–bovine interspecies somatic cell nuclear transfer (iSCNT), this study investigated the effect of different culture systems on the development, quality and gene expression profile of yak–bovine iSCNT embryo. Reconstructed embryos were cultured in modified synthetic oviductal fluid (mSOF) or relative defined culture medium (RDCM) with 5% or 20% oxygen tension. Relative mRNA abundance of Oct‐4, IFNT, IGF‐2, Bax, GPX‐1, SOD‐1, CAT and GSS was analysed in blastocysts with qRT‐PCR. The blastocyst formation rate in RDCM under 5% oxygen tension was significantly higher than that under 20% oxygen tension (P < 0.05). The total cell number of blastocyst derived from RDCM with 20% oxygen tension was lower than that of other groups, whereas the group of RDCM with 5% oxygen tension showed a beneficial effect on apoptosis index and tolerance to cryopreservation (P < 0.05). However, under the same oxygen tension, the mRNA abundance of IFNT of RDCM groups was higher than that of the mSOF groups. In addition, high oxygen tension during in vitro culture (IVC) with RDCM significantly increases the mRNA expression of oxidative stress‐related genes (GPX‐1, SOD‐1, CAT and GSS) (P < 0.05). 3, 4‐Dihydroxyflavone (DHF) during high oxygen tension was able to improve the cloned blastocyst formation rate in RDCM (P < 0.05). These results for the first time showed that low oxygen tension and RDCM could improve the developmental competence and quality and alleviate the oxidative stress for yak–bovine iSCNT embryo during IVC.
Evaluation of the performance of the microscopic observation drug susceptibility assay for diagnosis of extrapulmonary tuberculosis in China: A preliminary study
Authors: Huang Zikun , Xiong Guoliang , Luo Qing , Jiang Bixia , Li Weitin , Xu Xiaomeng , Li Junming 
Published: October 2013

AbstractBackground and objectiveWhile commercial liquid culture techniques have emerged over 20 years ago, Ziehl–Neelsen (ZN) smear microscopy remains the primary method for diagnosis of tuberculosis (TB) in China because of cost considerations. The microscopic observation drug susceptibility (MODS) assay has been evaluated in different parts of the world to determine whether it can give comparable result to commercial liquid techniques. However, most reports detail evaluation of sputum specimens. This study evaluated the performance of MODS assay for detection of Mycobacterium tuberculosis in extrapulmonary specimens in a Chinese population.MethodsA total of 173 samples, including pleural fluid (n = 112) and cerebrospinal fluid (CSF, n = 61) samples, were collected from patients suspected to have extrapulmonary TB and tested by ZN smear microscopy, Lowenstein–Jensen (LJ) culture and the MODS assay. Discordant results among MODS assay and the other two methods were resolved by 90‐day follow‐up evaluation for all suspected patients.ResultsThe sensitivity of the MODS assay on pleural fluid and CSF samples was 20.5% and 37.5%, respectively, while the specificity of MODS assay on both types of samples approximated 100%. The median time to culture results for the MODS and LJ methods was 14 days, 32 days for pleural fluid, and 9 days and 31 days for CSF samples, respectively.ConclusionsMODS assay is useful to diagnose extrapulmonary TB and may be an effective and affordable method in resource‐limited countries.
A Framework for Estimating the Adverse Health Effects of Contamination Events in Water Distribution Systems and its Application
Authors: Davis Michael J. , Janke Robert , Magnuson Matthew L. 
Published: October 2013

Intentional or accidental releases of contaminants into a water distribution system (WDS) have the potential to cause significant adverse health effects among individuals consuming water from the system. A flexible analysis framework is presented here for estimating the magnitude of such potential effects and is applied using network models for 12 actual WDSs of varying sizes. Upper bounds are developed for the magnitude of adverse effects of contamination events in WDSs and evaluated using results from the 12 systems. These bounds can be applied in cases in which little system‐specific information is available. The combination of a detailed, network‐specific approach and a bounding approach allows consequence assessments to be performed for systems for which varying amounts of information are available and addresses important needs of individual utilities as well as regional or national assessments. The approach used in the analysis framework allows contaminant injections at any or all network nodes and uses models that (1) account for contaminant transport in the systems, including contaminant decay, and (2) provide estimates of ingested contaminant doses for the exposed population. The approach can be easily modified as better transport or exposure models become available. The methods presented here provide the ability to quantify or bound potential adverse effects of contamination events for a wide variety of possible contaminants and WDSs, including systems without a network model.
A multiple cave deposit assessment of suitability of speleothem isotopes for reconstructing palaeo‐vegetation and palaeo‐temperature
Authors: Li Zheng‐Hua , Driese Steven G. , Cheng Hai 
Published: October 2013

AbstractThe suitability of speleothems for interpreting palaeoclimate is typically determined by using either the Hendy Test, overlapping analysis or long‐term cave environment monitoring. However, in many cases, these methods are not applicable, because a speleothem lacks clearly traceable layers for the Hendy Test, it is difficult to obtain an overlapping speleothem nearby, or long‐term cave monitoring is impractical. The authors propose a multiple cave deposit approach to assess the suitability of speleothems for palaeoclimate study. Speleothems collected from two sites within Raccoon Mountain Cave, Tennessee (USA) exhibit remarkable spatial variation (δ13C: −10·3‰ to −2·2‰) over a relatively short distance (ca 260 m). Drip water δ18O values exhibit a seasonal precipitation signal at Site 1 and an annual signal at Site 2. Combining field observations, water isotope analysis and trace‐element data, the authors propose that the speleothem formation at Site 1 and Site 2 tapped distinct sources of CO2: (i) CO2 derived from overlying soils for Site 1; and (ii) limestone dissolved inorganic carbon induced by ground water dissolution for Site 2. Using fresh cave deposits (modern speleothem) δ13C (100% C3 vegetation) as an analogue, a simple model was developed to estimate land surface vegetation for speleothems. The speleothem formation temperature estimated using fresh cave deposit δ18O values generally reflects the mean annual temperature in this region. This study indicates that spatial variations in carbon isotopes could be caused by different carbon sources dominating in different parts of the cave, which should be taken into consideration by researchers when using speleothem δ13C values to reconstruct temporal palaeo‐vegetation changes. This study demonstrates a practical sampling strategy for verifying suitability of speleothems for palaeo‐vegetation and palaeo‐temperature reconstructions by analysing multiple cave deposits, especially for cases in which the Hendy Test, parallel sampling and long‐term monitoring of cave environment are not feasible.
Race and Ethnic Variations in the Education‐Control‐Distress Model
Authors: Hill Terrence D. , Cook Hilary H. , Whitfield Keith E. 
Published: October 2013

ObjectiveResearch shows that education favors mental health, in part, because it helps to develop a greater sense of control. To this point, however, it is unclear whether this process varies according to race and ethnicity.MethodsBuilding on previous research, we use data collected from a large probability sample of Texas adults to test the extent to which the education‐control‐distress (E‐C‐D) model varies across three race and ethnic groups, including whites, blacks, and Mexican Americans.ResultsThe results of our simple mediation analyses validate the E‐C‐D model for each race/ethnic group. Our moderated mediation analyses suggest that the indirect effect of education on psychological distress through the sense of control is comparable across race/ethnic groups.ConclusionThe mediating influence of the sense of control does not appear to vary according to the three race/ethnic groups included in the study.
Tolerance and the Politics of Identity in the European Union
Authors: Arwine Alan , Mayer Lawrence 
Published: October 2013

ObjectivesThe basic research problem in this article is whether hostility toward out‐groups is a product of events or whether the degree of hostility toward out‐groups exists independently of such events in the form of a generalized bigotry.MethodsWe examine two countries that experienced threatening violent events from an unassimilated minority in order to determine if their levels of intolerance increased in the period between two runs of the World Values Survey when these violent events occurred. This article also examines six additional EU countries that did not experience such violent events.ResultsIn the six countries that did not experience violent events, the level of tolerance increased between the two waves of the World Values Survey while tolerance decreased in the two countries that experienced violent events.ConclusionsThe strongest factor in fostering intolerance toward out‐groups is a perception of a violent, existential threat to one's way of life. Our analyses tentatively suggest the following factor may exacerbate levels of intolerance: the presence and strength of a nativist or populist party of identity mobilizing a rejection of out‐groups.
Earth's spin and volcanic eruptions: evidence for mutual cause‐and‐effect interactions?
Authors: Palladino Danilo M. , Sottili Gianluca 
Published: October 2013

AbstractThe angular velocity of Earth's rotation shows decadal oscillations due to the lunisolar gravitational torque, as well as inter‐ or intra‐annual changes arising from the angular momentum exchange between the atmosphere and the solid Earth. The energies involved in the Length of Day (LOD) variations may affect the crustal deformation rate and seismic energy release on a global scale. We found significant correlation between the occurrences of major volcanic eruptions and theLODpattern since AD 1750. On a multiyear scale, eruption frequency worldwide increases withLODchanges. Moreover, the injection of sulphur gases into the atmosphere during major eruptions is accompanied by significant inter‐annualLODvariations. This provides evidence of complex mutual cause‐and‐effect interactions: stress changes induced by multiyear variations in Earth's spin may affect climactic volcanic activity; also, the atmosphere's dynamic response to volcanic plumes may result in global changes of wind circulation and climate, with consequentLODvariations.