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Arsenic Hazard ID

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The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Investigation of biochemical responses of Bacopa monnieri L. upon exposure to arsenate

Authors: Mishra, S; Srivastava, S; Dwivedi, S; Tripathi, RD (In Press) Environmental Toxicology. HERO ID: 1017520

[Less] Widespread contamination of arsenic (As) is recognized as a global problem due to its well-known accumulation . . . [More] Widespread contamination of arsenic (As) is recognized as a global problem due to its well-known accumulation by edible and medicinal plants and associated health risks for the humans. In this study, phytotoxicity imposed upon exposure to arsenate [As(V); 0-250 μM for 1-7 days] and ensuing biochemical responses were investigated in a medicinal herb Bacopa monnieri L. vis-à-vis As accumulation. Plants accumulated substantial amount of As (total 768 μg g(-1) dw at 250 μM As(V) after 7 days) with the maximum As retention being in roots (60%) followed by stem (23%) and leaves (17%). The level of cysteine and total nonprotein thiols (NP-SH) increased significantly at all exposure concentrations and durations. Besides, the level of metalloid binding ligands viz., glutathione (GSH) and phytochelatins (PCs) increased significantly at the studied concentrations [50 and 250 μM As(V)] in both roots and leaves. The activities of various enzymes viz., arsenate reductase (AR), glutathione reductase (GR), superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX), and catalase (CAT) showed differential but coordinated stimulation in leaves and roots to help plants combat As toxicity up to moderate exposure concentrations (50 μM). However, beyond 50 μM, biomass production was found to decrease along with photosynthetic pigments and total soluble proteins, whereas lipid peroxidation increased. In conclusion, As accumulation potential of Bacopa may warrant its use as a phytoremediator but if Bacopa growing in contaminated areas is consumed by humans, it may prove to be toxic for health. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2011.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Mixed arbuscular mycorrhizal (AM) fungal application to improve growth and arsenic accumulation of Pteris vittata (As hyperaccumulator) grown in As-contaminated soil

Authors: Leung, HM; Leung, AOW; Ye, ZH; Cheung, KC; Yung, KKL (In Press) Chemosphere. HERO ID: 1677595

[Less] A greenhouse pot experiment was conducted to study the effects of three types of single inoculum [indigenous . . . [More] A greenhouse pot experiment was conducted to study the effects of three types of single inoculum [indigenous mycorrhizas (IM) isolated from As mine, Glomus mosseae (GM) and Glomus intraradices (GI)] and two types of mixed inoculum (mixed with IM and either GM or GI) on the growth response of Pteris vittata (hyperaccumulator) and Cynodon dactylon (non-hyperaccumulator) at three levels of As concentrations (0, 100 and 200mgkg(-1)). Both mycorrhizal plants exhibited significantly higher biomass, and N and P accumulation in its tissue than the control. Among the mycorrhizal inoculum, the mixed inoculum IM/GM promoted substantially higher mycorrhizal colonization and arsenate reductase activity in P. vittata than C. dactylon, among all As levels. The portion of Paris arbuscular mycorrhizal structure (observed in colonized roots) together with the highest As translocation factor of 10.2 in P. vittata inoculated with IM/GM was also noted. It was deduced that IM/GM inoculum may be the best choice for field inoculation at any contaminated lands as the inoculum exhibited better adaptation to variable environmental conditions and hence benefited the host plants.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Indium diffusion and native oxide removal during the ALD of TiO2 films on InAs(100) surfaces

Authors: Ye, L; Gougousi, T (In Press) . HERO ID: 1797772

[Less] A thermal ALD process with tetrakis dimethyl amino titanium and H2O as reagents has been used to deposit . . . [More] A thermal ALD process with tetrakis dimethyl amino titanium and H2O as reagents has been used to deposit TiO2 films on native oxide and etched InAs(100) surfaces at 200°C. TiO2 was deposited on etched InAs(100) surface without the formation of undesirable interfacial layers. X-ray photoelectron spectroscopy data on a series of films of increasing thickness deposited on surfaces covered with native oxide has shown that the surface arsenic oxides are removed within the first 2-3 nm of film deposition. The indium oxides however after an initial reduction seem to persist and increase in intensity with film thickness. For a 6.4 nm TiO2 film, x-ray photoelectron spectroscopy depth profile data demonstrate accumulation of indium oxides at the TiO2 film surface. When the topmost layer of the indium/TiO2 film is removed then a sharp interface between the TiO2 film and the InAs substrate is detected. This observation demonstrates that the surface oxides diffuse through fairly thick TiO2 films and may subsequently be removed by reaction with the precursor and amine by products of the ALD reaction. These finding underscore the importance of diffusion in understanding the so called "interface clean-up" reaction and its potential impact on the fabrication of high quality InAs and other III-V based MOS devices.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Dicopper(II) metallacyclophanes with electroswitchable polymethyl-substituted para-phenylene spacers

Authors: Ferrando-Soria, J; Castellano, M; Ruiz-García, R; Cano, J; Julve, M; Lloret, F; Ruiz-Pérez, C; Pasán, J; Cañadillas-Delgado, L; Armentano, D; Journaux, Y; Pardo, E (In Press) HERO ID: 1797800

[Less] Double-stranded anionic dinuclear copper(II) metallacyclic complexes of the paracyclophane type [Cu2 . . . [More] Double-stranded anionic dinuclear copper(II) metallacyclic complexes of the paracyclophane type [Cu2 L2 ](4-) have been prepared by the Cu(II) -mediated self-assembly of different para-phenylenebis(oxamato) bridging ligands with either zero-, one-, or four-electron-donating methyl substituents (L=N,N'-para-phenylenebis(oxamate) (ppba; 1), 2-methyl- N,N'-para-phenylenebis(oxamate) (Meppba; 2), and 2,3,5,6-tetramethyl- N,N'-para-phenylenebis(oxamate) (Me4 ppba; 3)). These complexes have been isolated as their tetra-n-butylammonium (1 a-3 a), lithium(I) (1 b-3 b), and tetraphenylphosphonium salts (1 c-3 c). The X-ray crystal structures of 1 a and 3 c show a parallel-displaced π-stacked conformation with a smaller deviation from perpendicularity between the two benzene rings and the basal planes of the square planar Cu(II) ions when increasing the number of methyl substituents (average dihedral angles (ϕ) of 58.72(7) and 73.67(5)° for 1 a and 3 c, respectively). Variable-temperature (2.0-300 K) magnetic-susceptibility measurements show an overall increase of the intramolecular antiferromagnetic coupling with the number of methyl substituents onto the para-phenylene spacers (-J=75-95, 100-124, and 128-144 cm(-1) for 1 a-c, 2 a-c, and 3 a-c, respectively; H=-JS1 ×S2 ). Cyclic voltammetry (CV) measurements show a reversible one-electron oxidation of the double polymethyl-substituted para-phenylenediamidate bridging skeleton at a relatively low formal potential that decreases with the number of methyl substituents (E1 =+0.33, +0.24, and +0.15 V vs. SCE for 1-3, respectively). The monooxidized dicopper(II) π-radical cation species 3' prepared by the chemical oxidation of 3 with bromine exhibits intense metal-to-ligand charge-transfer (MLCT) transitions in the visible and near-IR (λmax =595 and 875 nm, respectively) regions together with a rhombic EPR signal with a seven-line splitting pattern due to hyperfine coupling with the nuclear spin of the two Cu(II) ions. Density functional (DF) calculations for 3' evidence a characteristic iminoquinonoid-type short-long-short alternating sequence of CN and CC bonds for both tetramethyl-para-phenylenediamidate bridges and a large amount of spin density of negative sign mainly delocalized along each of the four benzene C atoms directly attached to the amidate N atoms, which is in agreement with a fully delocalized π-stacked monoradical ligand description. Hence, the spins of the two Cu(II) ions (SCu =1/2) that are antiparallel aligned in 3 (OFF state) become parallel in 3' (ON state). Further developments may be then envisaged for this new permethylated dicopper(II) paracyclophane with a redox noninnocent ligand as a prototype for molecular magnetic electroswitch.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Synthesis and onwards coordination of an As(I) centered zwitterion

Authors: Dube, JW; Ragogna, PJ (In Press) Chemistry: A European Journal. HERO ID: 1797834

[Less] The bis(phosphino)borate ligand class is used as an anionic anchor to stabilize reactive, low coordinate . . . [More] The bis(phosphino)borate ligand class is used as an anionic anchor to stabilize reactive, low coordinate arsenic centers. The neutral, zwitterionic As(I) species, 2, is formed very cleanly, and isolated in good yields using cyclohexene as a halogen scavenger. The uniqueness of this heterocyclic As(I) compound is on display with the coordination to Group 6 metal centers, (2 M(CO)5 ; M=Cr, Mo, W). The arsenicmetal bond lengths are longer than the related AsPh3 complexes suggesting that compound 2 is a weak sigma donor. The metal complexes reveal a trigonal pyramidal arsenic atom, which provides the first experimental evidence for the presence of two "lone pairs" of electrons on the As(I) center. When more flexible and more electron-donating isopropyl substituents were used, an intermediate (compound 5) in the formation of low coordinate pnictogen compounds was crystallographically characterized. This structure, formally a base-stabilized dichloroarsenium cation, provides an alternative mechanistic proposal to the one described in the literature.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Effect of text messaging to deter early resumption of sexual activity after male circumcision for HIV prevention: A randomized controlled trial

Authors: Odeny, TA; Bailey, RC; Bukusi, EA; Simoni, JM; Tapia, KA; Yuhas, K; Holmes, KK; McClelland, RS (In Press) . HERO ID: 1797836

[Less] Background: Resumption of sex before complete wound healing after male circumcision may increase risk . . . [More] Background: Resumption of sex before complete wound healing after male circumcision may increase risk of postoperative surgical complications, and HIV acquisition and transmission. We aimed to determine the effect of text messaging to deter resumption of sex before 42 days postcircumcision. Methods: We conducted a randomized trial where men older than18 years who owned mobile phones and had just undergone circumcision were randomized to receive a series of text messages (n = 600) or usual care (n = 600). The primary outcome was self-reported resumption of sex before 42 days. Results: Sex before 42 days was reported by 139 of 491 (28.3%) men in the intervention group and 124 of 493 (25.2%) men in the control group [relative risk = 1.13, 95% confidence interval (CI): 0.91 to 1.38, P = 0.3]. Men were more likely to resume early if they were married or had a live-in sexual partner [adjusted relative risk (aRR) 1.57, 95% CI: 1.18 to 2.08, P < 0.01]; in the month before circumcision had 1 (aRR: 1.50, 95% CI: 1.07 to 2.12, P = 0.02) or more than 1 (aRR: 1.81, 95% CI: 1.24 to 2.66, P < 0.01) sexual partner(s); had primary school or lower education (aRR: 1.62, 95% CI: 1.33 to 1.97, P< 0.001); were employed (aRR: 1.35, 95% CI: 1.05 to 1.72, P = 0.02); or were 21–30 years old (aRR: 1.58, 95% CI: 1.01 to 2.47, P = 0.05), 31–40 years old (aRR: 1.91, 95% CI: 1.18 to 3.09, P < 0.01), or older than 40 years (aRR: 1.76, 95% CI: 1.04 to 2.97, P = 0.03) compared with younger than 21 years. Conclusions: Text messaging as used in this trial did not reduce early resumption of sex after circumcision. We identified key risk factors for early resumption that need to be considered in circumcision programs.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Randomised, double-blind, placebo-controlled trial to determine whether steroids reduce the incidence and severity of nephropathy in Henoch-Schönlein Purpura (HSP)

Authors: Dudley, J; Smith, G; Llewelyn-Edwards, A; Bayliss, K; Pike, K; Tizard, J (In Press) Archives of Disease in Childhood. HERO ID: 1797837

[Less] BACKGROUND: The long-term prognosis of Henoch-Schönlein Purpura (HSP) is predominantly determined by . . . [More] BACKGROUND: The long-term prognosis of Henoch-Schönlein Purpura (HSP) is predominantly determined by the extent of renal involvement. There is no consensus as to whether treatment with prednisolone at presentation can prevent or ameliorate the progression of nephropathy in HSP.

METHODS: Children under 18 years of age with new-onset HSP were randomly assigned to receive prednisolone or placebo for 14 days. The primary outcomes were (a) the presence of proteinuria at 12 months (defined as urine protein : creatinine ratio (UP : UC) >20 mg/mmol) and (b) the need for additional treatment (defined as the presence of hypertension requiring treatment or renal biopsy anomalies or the need for treatment of renal disease) during the 12 month study period.

RESULTS: 352 children were randomised. Of those patients with laboratory UP : UC results available at 12 months, 18/123 (15%) patients on prednisolone and 13/124 (10%) patients on placebo had UP : UC >20 mg/mmol. There was no significant difference in the proportion of patients with UP : UC >20 mg/mmol at 12 months between the treatment groups (OR (prednisolone/placebo)=1.46, 95% CI 0.68 to 3.14, n=247), even after adjusting for baseline proteinuria and medications known to affect proteinuria (adjusted OR=1.29, 95% CI 0.58 to 2.82, n=247). Similarly, there was no significant difference in the time needed for additional treatment between the two groups (hazard ratio (HR) (prednisolone/placebo)=0.53, 95% CI 0.18 to 1.59, n=323).

CONCLUSIONS: This is the largest trial of the role of steroids in children with HSP. We found no evidence to suggest that early treatment with prednisolone reduces the prevalence of proteinuria 12 months after disease onset in children with HSP.

TRIAL REGISTRATION NUMBER: ISRCTN71445600.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Correction: Arsenic exposure and cancer mortality in a US-based prospective cohort: The strong heart study

(In Press) Cancer Epidemiology Biomarkers and Prevention. HERO ID: 1797849


The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Protective role of AQP3 in UVA-induced NHSFs apoptosis via Bcl2 up-regulation

Authors: Xie, H; Liu, F; Liu, L; Dan, J; Luo, Y; Yi, Y; Chen, X; Li, J (In Press) Archives of Dermatological Research. HERO ID: 1519093

[Less] Aquaporin-3 (AQP3), a water/glycerol-transporting protein that facilitates water, urea, and glycerol . . . [More] Aquaporin-3 (AQP3), a water/glycerol-transporting protein that facilitates water, urea, and glycerol transport, can inhibit arsenite-induced apoptosis by up-regulating Bcl-2. However, whether it has a protective role in ultraviolet A (UVA)-induced apoptosis in normal human skin fibroblasts is not known. In this study, we demonstrate that mild UVA treatment fails to induce oxidative cell stress and apoptosis in normal human skin fibroblasts (NHSFs) overexpressing AQP3. After severe UVA irradiation, there was an increase in oxidative cell stress and apoptosis when AQP3 levels decreased. We also found that silencing AQP3 sensitized NHSFs to low-dose UVA. Overexpressing AQP3 was protective against high-dose UVA-induced oxidative stress and apoptosis. Besides, we observed that Bcl-2 may be involved in UVA-induced apoptosis. Our findings suggested that the water/glycerol-transporting protein AQP3 plays a role in resistance to UVA-induced apoptosis.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

p27 Suppresses cyclooxygenase-2 expression by inhibiting p38β and p38δ-mediated CREB phosphorylation upon arsenite exposure

Authors: Che, X; Liu, J; Huang, H; Mi, X; Xia, Q; Li, J; Zhang, D; Ke, Q; Gao, J; Huang, C (In Press) Biochimica et Biophysica Acta. HERO ID: 1579240

[Less] p27 is a cyclin-dependent kinase (CDK) inhibitor that suppresses a cell's transition from G0 to S phase, . . . [More] p27 is a cyclin-dependent kinase (CDK) inhibitor that suppresses a cell's transition from G0 to S phase, therefore acting as a tumor suppressor. Our most recent studies demonstrate that upon arsenite exposure, p27 suppresses Hsp27 and Hsp70 expressions through the JNK2/c-Jun- and HSF-1-dependent pathways, suggesting a novel molecular mechanism underlying the tumor suppressive function of p27 in a CDK-independent manner. We found that p27-deficiency (p27-/-) resulted in the elevation of cyclooxygenase-2 (COX-2) expression at transcriptional level, whereas the introduction of p27 brought back COX-2 expression to a level similar to that of p27+/+ cells, suggesting that p27 exhibits an inhibitory effect on COX-2 expression. Further studies identified that p27 inhibition of COX-2 expression was specifically due to phosphorylation of transcription factor cAMP response element binding (CREB) phosphorylation mediated by p38β and p38δ. These results demonstrate a novel mechanism underlying tumor suppression effect of p27 and will contribute to understanding of the overall mechanism of p27 tumor suppression in a CDK-independent manner.