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Li F, Ma L, Feng Y, Hu J, Ni N, Ruan Y, Shao Y. Generation and Characterization of HIV-1 Transmitted and Founder Virus Consensus Sequence from Intravenous Drug Users in Xinjiang, China. AIDS Res Hum Retroviruses 2017; 33:610-613. [PMID: 28073289 DOI: 10.1089/aid.2016.0316] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
HIV-1 transmission in intravenous drug users (IDUs) has been characterized by high genetic multiplicity and suggests a greater challenge for HIV-1 infection blocking. We investigated a total of 749 sequences of full-length gp160 gene obtained by single genome sequencing (SGS) from 22 HIV-1 early infected IDUs in Xinjiang province, northwest China, and generated a transmitted and founder virus (T/F virus) consensus sequence (IDU.CON). The T/F virus was classified as subtype CRF07_BC and predicted to be CCR5-tropic virus. The variable region (V1, V2, and V4 loop) of IDU.CON showed length variation compared with the heterosexual T/F virus consensus sequence (HSX.CON) and homosexual T/F virus consensus sequence (MSM.CON). A total of 26 N-linked glycosylation sites were discovered in the IDU.CON sequence, which is less than that of MSM.CON and HSX.CON. Characterization of T/F virus from IDUs highlights the genetic make-up and complexity of virus near the moment of transmission or in early infection preceding systemic dissemination and is important toward the development of an effective HIV-1 preventive methods, including vaccines.
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Ni N, Duquette D, Dumont MJ. Synthesis and characterization of zein-based cryogels and their potential as diesel fuel absorbent. Eur Polym J 2017. [DOI: 10.1016/j.eurpolymj.2017.04.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Li F, Feng Y, Ni N, Hu J, Ruan Y, Shao Y, Ma L. Five Near Full-Length Hepatitis C Virus Sequences Were Identified from HIV Coinfected Injection Drug Users of China. AIDS Res Hum Retroviruses 2017; 33:496-499. [PMID: 28075146 DOI: 10.1089/aid.2016.0317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
HIV and hepatitis C virus (HCV) share transmission routes, including contaminated blood transfusion, sexual intercourse, and needle-sharing in injection drug users (IDUs). We obtained five near full-length genome sequences of HCV isolated from five HIV-1-coinfected IDUs in Sichuan and Xinjiang provinces, China. By conducting reconstruction of neighbor-joining phylogenetic tree, our results revealed that the five isolates are of four different genotypes (1b, 3a, 6a, and 6n). The amino acid substitutions (170I) in XJN0021 related to resistant to protease inhibitors (grazoprevir) were also identified. The genetic diversity of these sequences uncovered more complicated transmission situation of HCV among IDUs in China.
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Ni N, Zhang D, Dumont MJ. Synthesis and characterization of zein-based superabsorbent hydrogels and their potential as heavy metal ion chelators. Polym Bull (Berl) 2017. [DOI: 10.1007/s00289-017-2017-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ni N, Wang ZL. [Meeting Minutes of 2016 International Congress of Oral Implantology: Pujiang Forum]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 2017; 52:53-54. [PMID: 28072996 DOI: 10.3760/cma.j.issn.1002-0098.2017.01.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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81
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Ni N, Cooper SJ, Williams R, Kemen N, McComb DW, Skinner SJ. Degradation of (La0.6Sr0.4)0.95(Co0.2Fe0.8)O3-δ Solid Oxide Fuel Cell Cathodes at the Nanometer Scale and below. ACS APPLIED MATERIALS & INTERFACES 2016; 8:17360-17370. [PMID: 27336290 DOI: 10.1021/acsami.6b05290] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The degradation of intermediate temperature solid oxide fuel cell (ITSOFC) cathodes has been identified as a major issue limiting the development of ITSOFCs as high efficiency energy conversion devices. In this work, the effect of Cr poisoning on (La0.6Sr0.4)0.95(Co0.2Fe0.8)O3-δ (LSCF6428), a particularly promising ITSOFC cathode material, was investigated on symmetrical cells using electrochemical impedance spectroscopy and multiscale structural/chemical analysis by advanced electron and ion microscopy. The systematic combination of bulk and high-resolution analysis on the same cells allows, for the first time, direct correlation of Cr induced performance degradation with subtle and localized structural/chemical changes of the cathode down to the atomic scale. Up to 2 orders of magnitude reduction in conductivity, oxygen surface exchange rate, and diffusivity were observed in Cr poisoned LSCF6428 samples. These effects are associated with the formation of nanometer size SrCrO4; grain boundary segregation of Cr; enhanced B-site element exsolution (both Fe and Co); and reduction in the Fe valence, the latter two being related to Cr substitution in LSCF. The finding that significant degradation of the cathode happens before obvious microscale change points to new critical SOFC degradation mechanisms effective at the nanometer scale and below.
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Wang Z, He F, Rao W, Ni N, Shen Q, Zhang D. Proteomic analysis of goat Longissimus dorsi muscles with different drip loss values related to meat quality traits. Food Sci Biotechnol 2016; 25:425-431. [PMID: 30263286 DOI: 10.1007/s10068-016-0058-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 12/06/2015] [Accepted: 12/08/2015] [Indexed: 01/29/2023] Open
Abstract
Longissimus dorsi muscles from 3 goat species were assigned to high and low drip loss groups. Physio-chemical properties, sarcomere length, and proteome profiles were investigated. The high drip loss group had lower pH, higher brightness, and higher shear force values, and shorter sarcomere lengths than the low drip loss group. 22 differential proteins were identified between high and low loss groups. α-Enolase, NADH dehydrogenase, pyruvate dehydrogenase E1, HSP27, superoxide dismutase, peroxiredoxin-2, myosin, and the myosin light chain were among these proteins, which were metabolic enzymes, stress response factors, and structural proteins that affected glycolysis, oxidation, and muscle contraction. Drip loss was probably produced via proteins involved in glycolysis, oxidation, and muscle contraction.
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Chen L, Li X, Ni N, Liu Y, Chen L, Wang Z, Shen QW, Zhang D. Phosphorylation of myofibrillar proteins in post-mortem ovine muscle with different tenderness. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2016; 96:1474-83. [PMID: 25950868 DOI: 10.1002/jsfa.7244] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 02/13/2015] [Accepted: 04/28/2015] [Indexed: 05/23/2023]
Abstract
BACKGROUND Tenderness is one of the most important quality attributes especially for beef and lamb. As protein phosphorylation and dephosphorylation regulate glycolysis, muscle contraction and turnover of proteins within living cells, it may contribute to the conversion of muscle to meat. The changes of myofibrillar protein phosphorylation in post-mortem ovine muscle with different levels of tenderness were investigated in this study. RESULTS The protein phosphorylation level (P/T ratio) of the tender group increased from 0.5 to 12 h post mortem and then decreased. The P/T ratio of tough group increased during 24 h post mortem, increasing faster from 0.5 to 4 h post mortem than from 4 to 24 h post mortem.The global phosphorylation level of tough meat was significantly higher than tender meat at 4, 12 and 24 h post mortem (P < 0.05). Protein identification revealed that most of the phosphoproteins were proteins with sarcomeric function; the others were involved in glycometabolism, stress response, etc. The phosphorylation levels of myofibrillar proteins, e.g. myosin light chain 2 and actin, were significantly different among groups of different tenderness and at different post-mortem time points (P < 0.05). CONCLUSION Protein phosphorylation may influence meat rigor mortis through contractile machinery and glycolysis, which in turn affect meat tenderness.
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Ye M, Wei W, Yang Z, Li Y, Cheng S, Wang K, Zhou T, Sun J, Liu S, Ni N, Jiang H, Jiang H. Rapid diagnosis of Propionibacterium acnes infection in patient with hyperpyrexia after hematopoietic stem cell transplantation by next-generation sequencing: a case report. BMC Infect Dis 2016; 16:5. [PMID: 26743541 PMCID: PMC4705617 DOI: 10.1186/s12879-015-1306-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 12/01/2015] [Indexed: 12/17/2022] Open
Abstract
Background The rapid determination of pathogenic agent is very important to clinician for guiding their clinical medication. However, current diagnostic methods are of limitation in many aspects, such as detecting range, time-consuming, specificity and sensitivity. In this report, we apply our new-developing pathogen detection method to clarify that Propionibacterium acnes is the causative agent of a two-year-old boy with juvenile myelomonocytic leukemia presenting clinical symptoms including serious rash and hyperpyrexia while traditional clinical methods of diagnosis fail to detect the pathogenic agent and multiple antimicrobial drugs are almost ineffective Propionibacterium acnes is confirmed to be the infectious agent by quantitative real-time polymerase chain reaction. Case presentation After haploidentical hematopoietic stem cell transplantation, a two-year-old boy with juvenile myelomonocytic leukemia presented to a pediatrist in a medical facility with hyperpyrexia and red skin rash which later changed to black skin rash all over his body. Traditional diagnostic assays were unrevealing, and several routine antimicrobial treatments were ineffective, including the vancomycin, meropenem, tobramycin, cefepime and rifampin. In this case, pediatrist resorted to the next-generation sequencing technology for uncovering potential pathogens so as to direct their use of specific drugs against pathogenic bacteria. Therefore, based on the BGISEQ100 (Ion Proton System) which performed sequencing-by-synthesis, with electrochemical detection of synthesis, and each such reaction coupled to its own sensor, which are in turn organized into a massively parallel sensor array on a complementary metal-oxidesemiconductor chip, we detect and identify the potential pathogens. As a result, we detected a significantly higher abundance of skin bacteria Propionibacterium acnes in patient’s blood than controls. It had been reported that patients infected by Propionibacterium acnes almost always had history of immunodeficiency, trauma or surgery. Considering this possible cause, antimicrobial treatment was adjusted to target this rare opportunistic pathogen. Fever and black skin rashes were rapidly reduced after administrating specific drugs against Propionibacterium acnes. Conclusion This case showed our new-developing pathogen detection method was a powerful tool in assisting clinical diagnosis and treatment. And it should be paid more attention to Propionibacterium acnes infection in clinical cases.
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Chen D, Gong L, Walsh TR, Lan R, Wang T, Zhang J, Mai W, Ni N, Lu J, Xu J, Li J. Infection by and dissemination of NDM-5-producing Escherichia coli in China. J Antimicrob Chemother 2015; 71:563-5. [PMID: 26542305 DOI: 10.1093/jac/dkv352] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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D'Elia E, Barg S, Ni N, Rocha VG, Saiz E. Self-healing graphene-based composites with sensing capabilities. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2015; 27:4788-4794. [PMID: 26178801 DOI: 10.1002/adma.201501653] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 05/19/2015] [Indexed: 06/04/2023]
Abstract
A self-healing composite is fabricated by confining a supramolecular polymer in a graphene network. The network provides electrical conductivity. Upon damage, the polymer is released and flows to reform the material. Healing is repeatable and autonomous. The composite is sensitive to pressure and flexion and recovers its mechanical and electrical properties even when rejoining cut surfaces after long exposure times.
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Boix M, Eslava S, Costa Machado G, Gosselin E, Ni N, Saiz E, De Coninck J. ATR-FTIR measurements of albumin and fibrinogen adsorption: Inert versus calcium phosphate ceramics. J Biomed Mater Res A 2015; 103:3493-502. [PMID: 25940865 DOI: 10.1002/jbm.a.35496] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 04/27/2015] [Accepted: 04/29/2015] [Indexed: 11/06/2022]
Abstract
Arthritis, bone fracture, bone tumors and other musculoskeletal diseases affect millions of people across the world. Nowadays, inert and bioactive ceramics are used as bone substitutes or for bone regeneration. Their bioactivity is very much dictated by the way proteins adsorb on their surface. In this work, we compared the adsorption of albumin and fibrinogen on inert and calcium phosphates ceramics (CaPs) using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to follow in situ protein adsorption on these materials. To this effect, we developed a sol-gel technique to control the surface chemistry of an ATR-FTIR detector. Hydroxyapatite adsorbed more albumin and β-tricalcium phosphate adsorbed more fibrinogen. Biphasic calcium phosphate presented the lowest adsorption among CaP for both proteins, illustrating the effect of surface heterogeneities. Inert ceramics adsorbed a lower amount of both proteins compared with bioactive ceramics. A significant change was observed in the conformation of the adsorbed protein versus the surface chemistry. Hydroxyapatite produced a larger loss of α-helix structure on albumin and biphasic calcium phosphate reduced β-sheet percentage on fibrinogen. Inert ceramics produced large α-helix loss on albumin and presented weak interaction with fibrinogen. Zirconia did not adsorb albumin and titanium dioxide promoted huge denaturalization of fibrinogen.
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Mounce AM, Yasuoka H, Koutroulakis G, Ni N, Bauer ED, Ronning F, Thompson JD. Detection of a spin-triplet superconducting phase in oriented polycrystalline U(2)PtC(2) samples using ^(195)Pt nuclear magnetic resonance. PHYSICAL REVIEW LETTERS 2015; 114:127001. [PMID: 25860768 DOI: 10.1103/physrevlett.114.127001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Indexed: 06/04/2023]
Abstract
Nuclear magnetic resonance (NMR) measurements on the ^{195}Pt nucleus in an aligned powder of the moderately heavy-fermion material U_{2}PtC_{2} are consistent with spin-triplet pairing in its superconducting state. Across the superconducting transition temperature and to much lower temperatures, the NMR Knight shift is temperature independent for field both parallel and perpendicular to the tetragonal c axis, expected for triplet equal-spin pairing superconductivity. The NMR spin-lattice relaxation rate 1/T_{1}, in the normal state, exhibits characteristics of ferromagnetic fluctuations, compatible with an enhanced Wilson ratio. In the superconducting state, 1/T_{1} follows a power law with temperature without a coherence peak giving additional support that U_{2}PtC_{2} is an unconventional superconductor. Bulk measurements of the ac susceptibility and resistivity indicate that the upper critical field exceeds the Pauli limiting field for spin-singlet pairing and is near the orbital limiting field, an additional indication for spin-triplet pairing.
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Hu J, Garner A, Ni N, Gholinia A, Nicholls RJ, Lozano-Perez S, Frankel P, Preuss M, Grovenor CR. Identifying suboxide grains at the metal–oxide interface of a corroded Zr–1.0%Nb alloy using (S)TEM, transmission-EBSD and EELS. Micron 2015; 69:35-42. [DOI: 10.1016/j.micron.2014.10.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 10/20/2014] [Accepted: 10/20/2014] [Indexed: 11/26/2022]
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Nicholls RJ, Ni N, Lozano-Perez S, London A, McComb DW, Nellist PD, Grovenor CRM, Pickard CJ, Yates JR. Crystal Structure of the ZrO Phase at Zirconium/Zirconium Oxide Interfaces. ADVANCED ENGINEERING MATERIALS 2015; 17:211-215. [PMID: 25892957 PMCID: PMC4393322 DOI: 10.1002/adem.201400133] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 05/29/2014] [Indexed: 06/04/2023]
Abstract
Zirconium-based alloys are used in water-cooled nuclear reactors for both nuclear fuel cladding and structural components. Under this harsh environment, the main factor limiting the service life of zirconium cladding, and hence fuel burn-up efficiency, is water corrosion. This oxidation process has recently been linked to the presence of a sub-oxide phase with well-defined composition but unknown structure at the metal-oxide interface. In this paper, the combination of first-principles materials modeling and high-resolution electron microscopy is used to identify the structure of this sub-oxide phase, bringing us a step closer to developing strategies to mitigate aqueous oxidation in Zr alloys and prolong the operational lifetime of commercial fuel cladding alloys.
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Pan H, Wang Z, Guo H, Ni N, Zhang D. Heterocyclic aromatic amines in meat products consumed in China. Food Sci Biotechnol 2014. [DOI: 10.1007/s10068-014-0284-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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92
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Ni N, Wang Z, Wang L, He F, Liu J, Gao Y, Zhang D. Reduction of sodium chloride levels in emulsified lamb sausages: The effect of lamb plasma protein on the gel properties, sensory characteristics, and microstructure. Food Sci Biotechnol 2014. [DOI: 10.1007/s10068-014-0155-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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93
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Barg S, Perez FM, Ni N, do Vale Pereira P, Maher RC, Garcia-Tuñon E, Eslava S, Agnoli S, Mattevi C, Saiz E. Mesoscale assembly of chemically modified graphene into complex cellular networks. Nat Commun 2014; 5:4328. [PMID: 24999766 PMCID: PMC4102120 DOI: 10.1038/ncomms5328] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 06/06/2014] [Indexed: 12/23/2022] Open
Abstract
The widespread technological introduction of graphene beyond electronics rests on our ability to assemble this two-dimensional building block into three-dimensional structures for practical devices. To achieve this goal we need fabrication approaches that are able to provide an accurate control of chemistry and architecture from nano to macroscopic levels. Here, we describe a versatile technique to build ultralight (density ≥1 mg cm−3) cellular networks based on the use of soft templates and the controlled segregation of chemically modified graphene to liquid interfaces. These novel structures can be tuned for excellent conductivity; versatile mechanical response (elastic-brittle to elastomeric, reversible deformation, high energy absorption) and organic absorption capabilities (above 600 g per gram of material). The approach can be used to uncover the basic principles that will guide the design of practical devices that by combining unique mechanical and functional performance will generate new technological opportunities. Graphene’s properties are well known, but turning this atomically thin material into three-dimensional devices remains a challenge. Here, the authors report an assembly process for chemically modified graphene into three-dimensional cellular networks, with control over the physical properties of the resulting materials.
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Ni N, Liu Q, Ren H, Wu D, Luo C, Li P, Wan JB, Su H. Ginsenoside Rb1 protects rat neural progenitor cells against oxidative injury. Molecules 2014; 19:3012-24. [PMID: 24662068 PMCID: PMC6271345 DOI: 10.3390/molecules19033012] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 02/13/2014] [Accepted: 03/03/2014] [Indexed: 12/17/2022] Open
Abstract
Ginseng, the root of Panax ginseng C.A. Meyer, has been used as a tonic to enhance bodily functions against various ailments for hundreds of years in Far Eastern countries without apparent adverse effects. Ginsenoside Rb1, one of the most active ingredients of ginseng, has been shown to possess various pharmacological activities. Here we report that Rb1 exhibits potent neuroprotective effects against oxidative injury induced by tert-butylhydroperoxide (t-BHP). Lactate dehydrogenase (LDH) assay demonstrated that incubation with 300 µm t-BHP for 2.5 h led to a significant cell loss of cultured rat embryonic cortex-derived neural progenitor cells (NPCs) and the cell viability was pronouncedly increased by 24 h pretreatment of 10 µm Rb1. TUNEL staining further confirmed that pretreatment of Rb1 significantly reduced the cell apoptosis in t-BHP-induced oxidative injury. Real time PCR revealed that pretreatment with Rb1 activated Nrf2 pathway in cultured NPCs and led to an elevated expression of HO-1. The results of the present study demonstrate that Rb1 shows a potent anti-oxidative effect on cultured NPCs by activating Nrf2 pathway.
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Huang Y, Ni N, Lu C, Duan Y. [Effects of hypoxia on the expression of glucocorticoid receptor and the anti-inflammatory action of dexamethasone in human alveolar epithelial cells]. Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2013; 29:39-41. [PMID: 23294717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
OBJECTIVE To study the changes in the expression levels of two isoforms of glucocorticoid receptor (GRα and GRβ) and the anti-inflammatory effect of dexamethasone in human alveolar epithelial cell under hypoxic conditions. METHODS Human alveolar epithelial cell line A549 was used as the model. Cells were cultured under normoxic (37°C, 950 mL/L air, 50 mL/L CO(2);) or hypoxic (37°C, 950 mL/L N(2);, 250 mL/L CO(2);) conditions for 24, 48 and 72 h, respectively. The expression levels of GRα and GRβ proteins in the cells were determined by Western blotting. Lipopolysaccharide (LPS, 10 μg/mL) and the different concentrations of dexamethasone (DEX, 10(-8);-10(-6); mol/L) were added together into the culture medium under normoxic or hypoxic conditions. 48 h later, radioimmunoassay (RIA) was used to measure the level of IL-8 in the culture supernatants. RESULTS The GRα protein level of the normoxia group was not significantly different from that of the hypoxia group at 24 h time point (P>0.05). But at the 48 h and 72 h time points, the GRα protein level of the hypoxia groups was lower than that of the corresponding normoxia groups (P<0.05, P<0.01, respectively). The GRα protein levels decreased progressively in the hypoxia groups (P<0.05), while the levels were not significantly different among the corresponding normoxia groups (P>0.05); The GRβ protein levels of the 24, 48, and 72 h hypoxia groups were not different from those in the corresponding normoxia groups (P>0.05). At 48 h after 10(-7); or 10(-6); mol/L DEX was added, IL-8 levels in the culture supernatants of the hypoxia groups were higher than those in the corresponding normoxia groups (P<0.05). CONCLUSION Hypoxia can down-regulate the GRα protein level in a time-dependent manner in A549 cells and impair the anti-inflammatory effect of DEX.
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Kim MG, Lamsal J, Heitmann TW, Tucker GS, Pratt DK, Khan SN, Lee YB, Alam A, Thaler A, Ni N, Ran S, Bud'ko SL, Marty KJ, Lumsden MD, Canfield PC, Harmon BN, Johnson DD, Kreyssig A, McQueeney RJ, Goldman AI. Effects of transition metal substitutions on the incommensurability and spin fluctuations in BaFe2As2 by elastic and inelastic neutron scattering. PHYSICAL REVIEW LETTERS 2012; 109:167003. [PMID: 23215117 DOI: 10.1103/physrevlett.109.167003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Indexed: 06/01/2023]
Abstract
The spin fluctuation spectra from nonsuperconducting Cu-substituted, and superconducting Co-substituted, BaFe(2)As(2) are compared quantitatively by inelastic neutron scattering measurements and are found to be indistinguishable. Whereas diffraction studies show the appearance of incommensurate spin-density wave order in Co and Ni substituted samples, the magnetic phase diagram for Cu substitution does not display incommensurate order, demonstrating that simple electron counting based on rigid-band concepts is invalid. These results, supported by theoretical calculations, suggest that substitutional impurity effects in the Fe plane play a significant role in controlling magnetism and the appearance of superconductivity, with Cu distinguished by enhanced impurity scattering and split-band behavior.
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McLeod JA, Buling A, Green RJ, Boyko TD, Skorikov NA, Kurmaev EZ, Neumann M, Finkelstein LD, Ni N, Thaler A, Bud'ko SL, Canfield PC, Moewes A. Effect of 3d doping on the electronic structure of BaFe2As2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:215501. [PMID: 22534111 DOI: 10.1088/0953-8984/24/21/215501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The electronic structure of BaFe(2)As(2) doped with Co, Ni and Cu has been studied by a variety of experimental and theoretical methods, but a clear picture of the dopant 3d states has not yet emerged. Herein we provide experimental evidence of the distribution of Co, Ni and Cu 3d states in the valence band. We conclude that the Co and Ni 3d states provide additional free carriers to the Fermi level, while the Cu 3d states are found at the bottom of the valence band in a localized 3d(10) shell. These findings help shed light on why superconductivity can occur in BaFe(2)As(2) doped with Co and Ni but not Cu.
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Wu Y, Liu Y, Ni N, Bao B, Zhang C, Lu L. High lead exposure is associated with telomere length shortening in Chinese battery manufacturing plant workers. Occup Environ Med 2012; 69:557-63. [PMID: 22539657 DOI: 10.1136/oemed-2011-100478] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVES Critically shortening of telomere length caused by various factors including environmental pollutants results in genome instability and age-associated diseases. Lead is one of the ubiquitous environmental and occupational pollutants, potentially affecting public health even at a low level. However, it is still unclear whether lead exposure affects telomere length. This study aims to investigate the association between lead exposure and peripheral white blood cell telomere length (PWBTL) in Chinese battery manufacturing plant workers. METHODS Lead levels in blood (BLL) and urine (ULL) were evaluated using flame atomic absorption spectrometry and lead mobilisation test for body lead burden (BLB) assessment, respectively. Quantitative PCR was employed to determine relative PWBTL. Univariate and multivariate analyses were performed to examine the associations of telomere length and other variables. RESULTS PWBTL averaged 1.76 (telomere/single-copy gene of albumin, T/S) in 144 battery plant workers. Significantly shorter PWBTL was observed in the workers with abnormal BLL and/or ULL than those with normal ones (1.66±0.63 vs 1.91±0.46, p=0.010). In all workers, PWBTL was in negative correlations with BLL, ULL, time working at the plant (working length) and body mass index. A strong inverse correlation was observed between PWBTL and BLB (r=-0.70, p<0.0001) in those with abnormal BLL and ULL. GLMSELECT model showed in the subgroup of inpatient workers, working length and BLB were significantly in inverse associations with PWBTL, while BLL was in weak positive association with PWBTL. CONCLUSIONS These findings suggest that PWBTL shortening is associated with long-term lead exposure and that PWBTL may be one of the targets damaged by lead toxicity.
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Grovenor CRM, Ni N, Hudson D, Yardley SS, Moore KL, Smith GDW, Lozano-Perez S, Sykes JM. Mechanisms of Oxidation of Fuel Cladding Alloys Revealed by High Resolution APT, TEM and SIMS Analysis. ACTA ACUST UNITED AC 2012. [DOI: 10.1557/opl.2012.521] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTAqueous corrosion of zirconium alloys has become the major factor limiting prolonged fuel campaigns in nuclear plant. Studies using SEM, TEM and electrochemical impedance measurements have been interpreted as showing a dense inner-most oxide layer, and an increased thickness of the layer has been correlated to a better corrosion resistance. Many authors have reported that an ‘intermediate layer’ at the metal oxide interface has a complex structure or/and stochiometry different to that of both the bulk oxide and bulk metal, sometimes claimed to be a suboxide phase. Diffraction evidence has suggested the presence of both cubic ZrO and rhombohedral Zr3O phases, and compositional analysis has revealed similar variations in local oxygen stoichiometry.We have carried out a systematic investigation of the structure and chemistry of the metal/oxide interface in samples of commercial ZIRLO corroded for times up to 180 days. We have developed new experimental techniques for the study of these interfaces both by Electron Energy Loss Spectroscopy (EELS) analysis in the Transmission Electron Microscope (TEM) and by Atom Probe Tomography (APT), and exactly the same samples have been investigated by both techniques. Our results show the development of a clearly defined suboxide layer of stoichiometry close to ZrO, and the subsequent disappearance of this layer at the first of the characteristic ‘breakaway’ transitions in the oxidation kinetics. We can correlate this behaviour with changes in the structure of the oxide layer, and particularly the development of interconnected porosity that links the corroding interface with the aqueous environment. Using high resolution SIMS analysis of isotopically spiked samples we demonstrate the penetration of the oxidising species through these porous outer oxide layers.
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Ni N, Lozano-Perez S, Sykes J, Grovenor C. Quantitative EELS analysis of zirconium alloy metal/oxide interfaces. Ultramicroscopy 2011; 111:123-30. [DOI: 10.1016/j.ultramic.2010.10.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Revised: 10/21/2010] [Accepted: 10/29/2010] [Indexed: 10/18/2022]
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