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110 Enhancement of developmental competence of immature oocytes supplementing with leukaemia inhibitory factor as a media supplement. Reprod Fertil Dev 2022. [DOI: 10.1071/rdv35n2ab110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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213P Type-1 diabetes restricts melanoma growth by reprogramming intra-tumoral T cell metabolism. IMMUNO-ONCOLOGY AND TECHNOLOGY 2022. [DOI: 10.1016/j.iotech.2022.100324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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3
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Search for continuous gravitational wave emission from the Milky Way center in O3 LIGO-Virgo data. Int J Clin Exp Med 2022. [DOI: 10.1103/physrevd.106.042003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Étiologies et pronostic des syndromes inflammatoires prolongés inexpliqués : à propos de 57 cas. Rev Med Interne 2021. [DOI: 10.1016/j.revmed.2021.03.268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Carbon estimation in the undershrub layer and the soil of a dry deciduous forest of West Bengal (eastern India). Trop Ecol 2020. [DOI: 10.1007/s42965-020-00108-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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The Oxylipin Signaling Pathway Is Required for Increased Aphid Attraction and Retention on Virus-Infected Plants. J Chem Ecol 2020; 46:771-781. [PMID: 32065342 DOI: 10.1007/s10886-020-01157-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 01/19/2020] [Accepted: 01/27/2020] [Indexed: 11/26/2022]
Abstract
Many studies have shown that virus infection alters phytohormone signaling and insect vector contact with hosts. Increased vector contact and movement among plants should increase virus survival and host range. In this study we examine the role of virus-induced changes in phytohormone signaling in plant-aphid interactions, using Pea enation mosaic virus (PEMV), pea aphids (Acyrthosiphon pisum), and pea (Pisum sativum) as a model. We observed that feeding by aphids carrying PEMV increases salicylic acid and jasmonic acid accumulation in pea plants compared to feeding by virus-free aphids. To determine if induction of the oxylipin jasmonic acid is critical for aphid settling, attraction, and retention on PEMV-infected plants, we conducted insect bioassays using virus-induced gene silencing (VIGS), an oxylipin signaling inducer, methyl jasmonate (MeJA), and a chemical inhibitor of oxylipin signaling, phenidone. Surprisingly, there was no impact of phenidone treatment on jasmonic acid or salicylic acid levels in virus-infected plants, though aphid attraction and retention were altered. These results suggest that the observed impacts of phenidone on aphid attraction to and retention on PEMV-infected plants are independent of the jasmonic acid and salicylic acid pathway but may be mediated by another component of the oxylipin signaling pathway. These results shed light on the complexity of viral manipulation of phytohormone signaling and vector-plant interactions.
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Structural and Optical Properties of GaN Film on Copper and Graphene/Copper Metal Foils Grown by Laser Molecular Beam Epitaxy. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2020; 20:3929-3934. [PMID: 31748098 DOI: 10.1166/jnn.2020.17536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We report the direct growth of crystalline GaN on bare copper (Cu) and monolayer-graphene/Cu metal foils using laser molecular beam epitaxy technique at growth temperature of 700 °C. The surface morphology investigated with field emission scanning electron microscopy revealed that the size of GaN grains for film grown on bare Cu falls in range of 90 to 160 nm whereas large grains with size of ˜200 to 600 nm was obtained for GaN grown on graphene/Cu foil under similar growth condition. The transverse optical mode of cubic GaN and E₂ (high) phonon mode for wurtzite GaN phases were obtained on the GaN film grown on Cu and graphene/Cu metal foils as deduced by Raman spectroscopy. The photoluminescence (PL) spectroscopy studies showed that the near band edge emission peaks for GaN on Cu and graphene/Cu consist two major peaks at 3.26 and 3.4 eV, corresponding to cubic and wurtzite GaN, respectively. The Raman and PL studies disclosed that the mixed phase growth of GaN occurs on these foils and better structural and optical quality for GaN on graphene/Cu foil. The direct growth of GaN on two dimensional graphene on polycrystalline metal foils is beneficial various transferrable and flexible opto-electronics device applications.
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Sorting Fermionization from Crystallization in Many-Boson Wavefunctions. Sci Rep 2019; 9:17873. [PMID: 31784539 PMCID: PMC6884621 DOI: 10.1038/s41598-019-53179-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 10/23/2019] [Indexed: 11/23/2022] Open
Abstract
Fermionization is what happens to the state of strongly interacting repulsive bosons interacting with contact interactions in one spatial dimension. Crystallization is what happens for sufficiently strongly interacting repulsive bosons with dipolar interactions in one spatial dimension. Crystallization and fermionization resemble each other: in both cases - due to their repulsion - the bosons try to minimize their spatial overlap. We trace these two hallmark phases of strongly correlated one-dimensional bosonic systems by exploring their ground state properties using the one- and two-body density matrix. We solve the N-body Schrödinger equation accurately and from first principles using the multiconfigurational time-dependent Hartree for bosons (MCTDHB) and for fermions (MCTDHF) methods. Using the one- and two-body density, fermionization can be distinguished from crystallization in position space. For N interacting bosons, a splitting into an N-fold pattern in the one-body and two-body density is a unique feature of both, fermionization and crystallization. We demonstrate that this splitting is incomplete for fermionized bosons and restricted by the confinement potential. This incomplete splitting is a consequence of the convergence of the energy in the limit of infinite repulsion and is in agreement with complementary results that we obtain for fermions using MCTDHF. For crystalline bosons, in contrast, the splitting is complete: the interaction energy is capable of overcoming the confinement potential. Our results suggest that the spreading of the density as a function of the dipolar interaction strength diverges as a power law. We describe how to distinguish fermionization from crystallization experimentally from measurements of the one- and two-body density.
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Negative Differential Resistance Behavior of the Iron Storage Protein Ferritin. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:3126-3135. [PMID: 29412680 DOI: 10.1021/acs.langmuir.7b04356] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Realization of useful nanometer length scale devices in which metalloproteins are junction-confined in a distinct molecular arrangement for generating practical electronic signals (e.g., in bioelectronic switch configuration) is elusive till date. This is mostly due to difficulties in observing an electronically appropriate signal (i.e., reproducible and controllable), when studied under junction-assembled condition. A useful "ON"-"OFF" behavior, based on the negative differential resistance (NDR) peak characteristics in the current-voltage response curves, acquired using metal-insulator-metal (MIM) configuration, has been observed only in the case of a few proteins, namely, azurin, cytochrome c, bacteriorhodopsin, so far. The case of NDR in ferritin, an iron storage protein having a semiconducting iron core consisting of few thousands of iron atoms connected in an oxide network, has not been studied in the MIM configuration where single (or a few) molecule(s) are junction-trapped, for example, as in the case of local probe configuration of scanning probe microscopy. The present study by scanning tunneling microscopy (STM), using the naturally occurring iron-containing ferritin (human liver), as well as different iron-loaded ferritins, provides clear indication of the capability of ferritins to be NDR capable, at varying sweep conditions. As ferritin can be tailor-made in a structurally conserved manner, metal core-reconstituted ferritins, that is, Mn(III)-ferritin, Cu(II)-ferritin, and Ag-ferritin, were prepared. A correlation between the NDR peak signatures, as observed in the respective current-voltage response curves of these reconstituted ferritins, and the nature of the metal core is demonstrated. In support of our earlier proposition, here, we affirm that the ferritin protein behaves as a conductor-insulator (metal core-polypeptide shell) composite, where the overall electronic structure of the material can alter as a function of the nature of the conducting filler placed inside the insulated matrix.
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Single crystal Er 3+ : YAG fibers with tailored refractive index profiles. APPLIED OPTICS 2018; 57:362-370. [PMID: 29328186 DOI: 10.1364/ao.57.000362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 12/10/2017] [Indexed: 06/07/2023]
Abstract
Erbium-doped yttrium aluminum garnet (Er3+:YAG) rods were inserted inside undoped tubes and grown into single-crystal fibers of a diameter of 300 μm using the laser-heated pedestal growth technique. Growth at various rates resulted in radially graded distributions of Er3+ dopant ions, as observed using laser-induced fluorescence imaging. Profiles of the refractive index were measured using cross-sectional reflectometry in a microscope. Dopant distributions and the corresponding index profiles were compared with thermal diffusion theory to determine the inter-diffusion coefficient of Y3+ and Er3+ ions at 2000°C, yielding an estimated value of D=(9.10±0.8)×10-11 m2/s. This work constitutes a step toward controlled growth of fibers with high thermal conductivities, low Brillouin gain, and waveguiding properties required for high-power optical amplifier and laser applications.
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Benefit of ivabradine combined with beta-blocker in comparison with increased dose of beta-blocker in stable angina. Indian Heart J 2014. [DOI: 10.1016/j.ihj.2014.10.043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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Density of states in graphene with vacancies: midgap power law and frozen multifractality. PHYSICAL REVIEW LETTERS 2014; 113:186802. [PMID: 25396386 DOI: 10.1103/physrevlett.113.186802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Indexed: 06/04/2023]
Abstract
The density of states ϱ(E) of graphene is investigated numerically and within the self-consistent T-matrix approximation in the presence of vacancies within the tight binding model. The focus is on compensated disorder, where the concentration of vacancies n(A) and n(B) in both sublattices is the same. Formally, this model belongs to the chiral symmetry class BDI. The onlinear sigma model predicts for BDI a Gade-type singularity ϱ(E)∼|E|(-1)exp[-|log(E)|(-1/x)]. Our numerical data are comparable to this result in a preasymptotic regime that gives way, however, at even lower energies to ϱ(E)∼E(-1)|log(E)|(-x̃), 1≤x̃<2. We take this finding as evidence that, similar to the case of dirty d-wave superconductors, generic bipartite random hopping models may also exhibit unconventional (strong-coupling) fixed points for certain kinds of randomly placed scatterers if these are strong enough. Our research suggests that graphene with (effective) vacancy disorder is a physical representative of such systems.
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The effects of selenium and the GPx-1 selenoprotein on the phosphorylation of H2AX. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1830:3399-406. [PMID: 23518201 PMCID: PMC3668444 DOI: 10.1016/j.bbagen.2013.03.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 02/17/2013] [Accepted: 03/06/2013] [Indexed: 11/22/2022]
Abstract
BACKGROUND Significant data supports the health benefits of selenium although supplementation trials have yielded mixed results. GPx-1, whose levels are responsive to selenium availability, is implicated in cancer etiology by human genetic data. Selenium's ability to alter the phosphorylation of the H2AX, a histone protein that functions in the reduction of DNA damage by recruiting repair proteins to the damage site, following exposure to ionizing radiation and bleomycin was investigated. METHODS Human cell lines that were either exposed to selenium or were transfected with a GPx-1 expression construct were exposed to ionizing radiation or bleomycin. Phosphorylation of histone H2AX was quantified by flow cytometry and survival by the MTT assay. Phosphorylation of the Chk1 and Chk2 checkpoint proteins was quantified by western blotting. RESULTS In colon-derived cells, selenium increases GPx-1 and attenuated H2AX phosphorylation following genotoxic exposures while the viability of these cells was unaffected. MCF-7 cells and transfectants that express high GPx-1 levels were exposed to ionizing radiation and bleomycin, and H2AX phosphorylation and cell viability were assessed. GPx-1 increased H2AX phosphorylation and viability following the induction of DNA damage while enhancing the levels of activated Chk1 and Chk2. CONCLUSIONS Exposure of mammalian cells to selenium can alter the DNA damage response and do so by mechanisms that are dependent and independent of its effect on GPx-1. GENERAL SIGNIFICANCE Selenium and GPx-1 may stimulate the repair of genotoxic DNA damage and this may account for some of the benefits attributed to selenium intake and elevated GPx-1 activity.
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Methylglyoxal induces mitochondria-dependent apoptosis in sarcoma. BIOCHEMISTRY (MOSCOW) 2011; 76:1164-71. [DOI: 10.1134/s0006297911100105] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Differential inhibition/inactivation of mitochondrial complex I implicates its alteration in malignant cells. BIOCHEMISTRY (MOSCOW) 2011; 76:1051-60. [DOI: 10.1134/s0006297911090100] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Diffusion and criticality in undoped graphene with resonant scatterers. PHYSICAL REVIEW LETTERS 2010; 105:266803. [PMID: 21231699 DOI: 10.1103/physrevlett.105.266803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Indexed: 05/30/2023]
Abstract
A general theory is developed to describe graphene with an arbitrary number of isolated impurities. The theory provides a basis for an efficient numerical analysis of the charge transport and is applied to calculate the Dirac-point conductivity σ of graphene with resonant scatterers. In the case of smooth resonant impurities the symmetry class is identified as DIII and σ grows logarithmically with increasing impurity concentration. For vacancies (or strong on-site potential impurities, class BDI) σ saturates at a constant value that depends on the vacancy distribution among two sublattices.
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Molecular characterization of tumor associated glyceraldehyde-3-phosphate dehydrogenase. BIOCHEMISTRY (MOSCOW) 2009; 74:717-27. [PMID: 19747091 DOI: 10.1134/s0006297909070037] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Here we describe the purification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from normal leukocytes of healthy subjects and leukocytes of chronic myeloid leukemia (CML) patients and from normal mouse muscle and sarcoma tissue. The data indicate that some properties of GAPDH of leukocytes of CML patients and sarcoma tissues are similar and also similar to those of EAC (Ehrlich ascites carcinoma) cellular GAPDH but distinctly different from those of the normal cellular GAPDH. Polyclonal antiserum raised against the 54 kDa subunit of EAC cell GAPDH strongly reacted with GAPDH of leukocytes of CML patients and sarcoma tissue GAPDH only and weakly reacted with GAPDH of normal leukocyte and normal muscle and a variety of other tissues of normal rats. Both the subunits of GAPDH of sarcoma tissues were partially sequenced from the N-terminus and compared with the known sequences of GAPDH. The altered properties of GAPDH of three different malignant sources might be common feature of all malignant cells, which is discussed in relation to glycolysis and malignant aberrations.
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Microstructures of a Pt/Ni/C multilayer system: an X-ray reflectivity and ion scattering study. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2007; 7:2182-5. [PMID: 17655014 DOI: 10.1166/jnn.2007.791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Microstructural characterization of a synthetic periodic and graded Pt/Ni/C multilayer system by X-ray reflectivity and ion scattering techniques is presented. The experimental reflectivity data are fitted with a theoretical multi-trilayer model with graded periodicity which increases from substrate to film surface along the surface normal direction. The increase in periodicity is found to be due to a linear increase in C-layer thickness from the bottom to the top, with a change of slope nearly at the middle of the multilayer stack. The thicknesses of Pt and Ni layers, the variation of C-layer thickness with depth, interface roughness of Pt/Ni, Ni/C, C/Pt interfaces are determined from the analysis of the reflectivity data. Rutherford backscattering spectrometry measurements were also made on the same sample. Simulated Rutherford back scattering spectrometry data using the parameters obtained from the analysis of the X-ray reflectivity data agree well with the measured Rutherford backscattering spectrum.
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Probing atomic migration in nanostructured multilayers: application of X-ray standing wave fields. PHYSICAL REVIEW LETTERS 2007; 98:196103. [PMID: 17677636 DOI: 10.1103/physrevlett.98.196103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2007] [Indexed: 05/16/2023]
Abstract
X-ray standing wave fields, excited in periodic nanostructured multilayers during Bragg diffraction, have been used to probe atomic migration in multilayers. Ion beam induced migration of Fe impurity atoms from the C layers to the Pt layers in a Pt(Fe)/C(Fe) multilayer, where each layer is about 2 nm thick, has been detected. With a depth resolution better than 0.2 nm of this technique, the direction of Fe migration (here outward) and the change of Fe concentration in C (also Pt) layers have been determined. The results of such measurements are important for understanding the properties of multilayers, for example, the evolution of ferromagnetism in the present example [Dev, Microelectron. Eng. 83, 1721 (2006)10.1016/j.mee.2006.01.230].
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Substituted hydrophobic and hydrophilic residues at methionine-68 influence the chaperone-like function of alphaB-crystallin. Mol Cell Biochem 2001. [PMID: 11451372 DOI: 10.1023/a: 1010834107809] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Amino acid residues 57-69 in alphaB-crystallin have been implicated as a target protein binding site. Moreover, a direct correlation between the extent of alpha-crystallin hydrophobicity and chaperone-like activity has been demonstrated. The purpose of this study was to mutate a moderately hydrophobic residue Met-68 (M-68) in the above region to strongly hydrophobic and hydrophilic residues and show whether chaperoning ability is affected with or without structural changes. Mutation of M-68 to Val, Ile or Thr did not result in significant changes in molecular mass and secondary and tertiary structures. However, the Val and Ile mutants showed significant improvement and the Thr mutant showed substantial loss in chaperone activity. Differences in chaperone function in the absence of any structural changes confirmed that the hydrophobicity or hydrophilicity of the substituted amino acid in the putative target protein binding site was the only contributing factor.
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Substituted hydrophobic and hydrophilic residues at methionine-68 influence the chaperone-like function of alphaB-crystallin. Mol Cell Biochem 2001; 220:127-33. [PMID: 11451372 DOI: 10.1023/a:1010834107809] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Amino acid residues 57-69 in alphaB-crystallin have been implicated as a target protein binding site. Moreover, a direct correlation between the extent of alpha-crystallin hydrophobicity and chaperone-like activity has been demonstrated. The purpose of this study was to mutate a moderately hydrophobic residue Met-68 (M-68) in the above region to strongly hydrophobic and hydrophilic residues and show whether chaperoning ability is affected with or without structural changes. Mutation of M-68 to Val, Ile or Thr did not result in significant changes in molecular mass and secondary and tertiary structures. However, the Val and Ile mutants showed significant improvement and the Thr mutant showed substantial loss in chaperone activity. Differences in chaperone function in the absence of any structural changes confirmed that the hydrophobicity or hydrophilicity of the substituted amino acid in the putative target protein binding site was the only contributing factor.
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The effect of glutathione upon chaperone activity of alpha-crystallin is probably mediated through target modulation. Ophthalmic Res 2000; 30:271-9. [PMID: 9704329 DOI: 10.1159/000055484] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We studied the effect of the presence of glutathione, both reduced (GSH) and oxidized (GSSG), on the chaperone activity of alpha-crystallin towards thermal aggregation of gamma 2-crystallin. Results showed that while GSH enhanced the chaperone activity of alpha-crystallin, GSSG appeared to diminish it to some extent. When, however, the effect of the presence of glutathione was studied in the absence of alpha-crystallin, the nature of their action was found to be almost similar to that observed in its presence. These results suggest that glutathiones probably modulate the target protein which ultimately influences the chaperone activity of alpha-crystallin.
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Mutation of R116C results in highly oligomerized alpha A-crystallin with modified structure and defective chaperone-like function. Biochemistry 2000; 39:1420-6. [PMID: 10684623 DOI: 10.1021/bi991656b] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An autosomal dominant congenital cataract in human is associated with mutation of Arg-116 to Cys (R116C) in alpha A-crystallin. To investigate the molecular basis of cataract formation, rat alpha A-crystallin cDNA was cloned into pET-23d(+), and the site-directed mutants S142C (similar to wild-type human alpha A) and R116C/S142C or R116C (similar to human R116C variant) were generated. These were expressed in E. coli and the recombinant alpha A-crystallins purified by Sephacryl size-exclusion chromatography. The chaperone-like function of mutant R116C determined at 37 degrees C with insulin and alcohol dehydrogenase as target proteins was about 40% lower than those of wild-type and mutant S142C. Based on size-exclusion chromatography data, the oligomeric size of the R116C mutant was about 2000 kDa at 25 degrees C, 1400 kDa at 37 degrees C, and 900 kDa at 45 degrees C. In comparison, alpha A-wild-type and alpha A-S142C ranged from 477 to 581 kDa. Heat stability studies corroborated the effect of temperature on the dynamic quaternary structure of the R116C mutant. Circular dichroism spectra showed secondary and tertiary structural changes, and ANS fluorescence spectra showed loss of surface hydrophobicity in the R116C mutant. These findings suggest that the molecular basis for the congenital cataract with the alpha A-R116C mutation is due to the generation of a highly oligomerized alpha A-crystallin having a modified structure and decreased chaperone-like function.
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Synthesis and antiviral studies of unsaturated analogues of isomeric dideoxynucleosides. NUCLEOSIDES & NUCLEOTIDES 1999; 18:2379-95. [PMID: 10639747 DOI: 10.1080/07328319908044614] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Novel isomeric dideoxynucleosides with unsaturation in the carbohydrate moiety have been synthesized. For example, isod4A was synthesized through a rearrangement reaction involving a cyclonucleoside. Support for the structures of both purine and pyrimidine d4 compounds came from UV, NMR, HRMS and single crystal X-ray data. Interestingly, the single crystal X-ray data for isod4C shows that the base is almost orthogonal to the carbon-carbon double bond of the sugar moiety. Consistent with this is the observation that the UV data of this compound does not show a bathochromic shift compared to the saturated compound implying that the pi-bond is not in conjugation with the pyrimidine base.
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Abstract
Methodologies for the synthesis of novel isomeric dideoxynucleosides with unsaturation in the carbohydrate moiety have been developed. An example of the synthesis (Isod4A) is presented. Antiviral studies are in progress.
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Small-area analysis: targeting high-risk areas for adolescent pregnancy prevention programs. FAMILY PLANNING PERSPECTIVES 1998; 30:173-6. [PMID: 9711455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
CONTEXT Traditional methods of identifying areas in need of adolescent pregnancy prevention programs may miss small localities with high levels of adolescent childbearing. METHODS Birthrates for 15-17-year-olds were computed for all California zip codes, and the zip codes with birthrates in the 75th percentile were identified. Panels of local experts in adolescent pregnancy reviewed these "hot spots" for accuracy and grouped them into potential project areas, based on their demographics, geography and political infrastructure. RESULTS In all, 415 zip codes exceeded the 75th-percentile cut-off point of 62.8 births per 1,000, and 210 of them differed significantly from the state average of 44.5 per 1,000 for 15-17-year-olds. While all had high adolescent birthrates, they varied greatly in racial and ethnic mix, poverty and educational attainment, and certain perinatal measures such as inadequate prenatal care and repeat pregnancy. CONCLUSIONS The use of zip code-level data holds promise for more effective program planning and intervention.
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Behavioral and experiential patterns of avoidantly and securely attached women across adulthood: a 31-year longitudinal perspective. J Pers Soc Psychol 1998. [PMID: 9457783 DOI: 10.1037//0022-3514.74.1.211] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Attachment patterns of women avoidantly or securely attached at age 52 were studied using a 31-year longitudinal design and multiple perspectives, including life outcomes, observer descriptions of behavioral and personality characteristics, and self-reports of working models collected at ages 21, 27, 43, and 52. Findings from these diverse data sources provide evidence for the continuity of the behavioral and experiential patterns associated with attachment styles across adulthood. Avoidant compared with secure participants (a) experienced diverging relationship trajectories that were less happy and less steady, (b) showed a consistent pattern of behavioral and personality characteristics, including interpersonal distance, defensiveness, and vulnerability, as assessed by observers, (c) reported distinct and longitudinal consistent internal working models characterized by distrustful self-reliance and interpersonal and emotional distance, and (d) had childhood environments that afforded fewer opportunities for developing close interpersonal ties.
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Interaction of H(+)-ions with alpha-crystallin: solvent accessibility of ionizable side chains and surface charge. Biophys Chem 1998; 70:147-60. [PMID: 9540206 DOI: 10.1016/s0301-4622(97)00130-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Interaction of H(+)-ions with alpha-crystallin from goat lens has been studied at three different ionic strengths using the potentiometric titration method. Titrations have also been carried out in the presence of 1.5 M and 6 M GuHCl (guanidine hydrochloride). The isoionic pH of the protein in water and the effect of KCl on it have been determined. Titration curves have been found to be reversible between pH 3 to 9.25 at all ionic strengths. To aid in the data analyses, the reactivities of alpha-crystallin lysine residues to trinitrobenzenesulfonic acid have been determined in this work. For alpha-crystallin aggregate, 130 +/- 2 histidine side chains out of a total of 300 and about 134 +/- 4 lysine side chains out of 310 have been found to be inaccessible to the solvent in the native condition. The remaining titratable side chains determine the surface charge of the native protein. In 1.5 M GuHC1, however, the nontitratable histidine side chains are found to be available for titration as are the nontitratable lysine and tyrosine side chains in 6M GuHC1. The theoretical titration curve computed on the basis of Linderstrøm-Lang model is found to fit quite comfortably with the experimental one between pH 4.6 and 9.25. The pKint value for beta gamma-carboxyl side chains has been found to be 5.18 which is somewhat higher than usual indicating that the carboxyl groups in the protein are probably in some constrained condition which is released in the presence of a denaturant. Below pH 4.6, there begins a conformational change in the alpha-crystallin aggregate as is corroborated from the circular dichroism studies. The value of electrostatic interaction factor w which remains more or less constant between pH 4.6 and 9.25 is also found to gradually fall off below pH 4.6.
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Behavioral and experiential patterns of avoidantly and securely attached women across adulthood: a 31-year longitudinal perspective. J Pers Soc Psychol 1998; 74:211-23. [PMID: 9457783 DOI: 10.1037/0022-3514.74.1.211] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Attachment patterns of women avoidantly or securely attached at age 52 were studied using a 31-year longitudinal design and multiple perspectives, including life outcomes, observer descriptions of behavioral and personality characteristics, and self-reports of working models collected at ages 21, 27, 43, and 52. Findings from these diverse data sources provide evidence for the continuity of the behavioral and experiential patterns associated with attachment styles across adulthood. Avoidant compared with secure participants (a) experienced diverging relationship trajectories that were less happy and less steady, (b) showed a consistent pattern of behavioral and personality characteristics, including interpersonal distance, defensiveness, and vulnerability, as assessed by observers, (c) reported distinct and longitudinal consistent internal working models characterized by distrustful self-reliance and interpersonal and emotional distance, and (d) had childhood environments that afforded fewer opportunities for developing close interpersonal ties.
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Chemical modifications and dissociation characteristics of tyrosine and tryptophan residues in alpha-crystallin. INDIAN JOURNAL OF BIOCHEMISTRY & BIOPHYSICS 1997; 34:419-28. [PMID: 9594422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A quantitative estimation of surface accessibility of aromatic residues in alpha-crystallin from goat lens has been accomplished by chemical modifications using different specific reagents having varying sizes. Results of modification of tyrosine residues with N-acetylimidazole and tetranitromethane when combined with those of ionization studies carried out with hydroxyl ions having the smallest size reveal different classes of tyrosine residues in the native protein: 78 +/- 2 residues have been found to be easily available for modification; among the rest, 94 +/- 2 residues appear to be comparatively less exposed to the reagents while 28 +/- 2 residues are found to be completely unavailable for modification in the native protein and are modified only when the protein is denatured. Modification of tryptophan residues with H2O2 also indicates different classes of these residues available for oxidation at different concentrations of the oxidant. 34 +/- 2 residues of tryptophan are found to be easily oxidized at a lower concentration of H2O2 during the first phase of the reaction. The remaining tryptophan residues appear to be less exposed to the reagent. This is also corroborated from the studies of reactivities of these residues towards another specific but bulkier reagent, 2-hydroxy-5-nitrobenzyl bromide. These surface exposed aromatic residues in alpha-crystallin may be considered to be vulnerable to in vivo oxidative modifications forming insoluble aggregates which may finally contribute to the formation of cataract.
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Identification and characterization of some PR-proteins induced by kitazin and Rhizoctonia solani causing sheath blight of rice. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 1997; 35:644-9. [PMID: 9357170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Significant reduction (68.38%) in sheath blight disease of rice was noticed when foliar spray of a systemic fungicide, kitazin (480 micrograms mg-1), was applied twice at an interval of 2 days before inoculation. SDS-PAGE analysis of proteins of Rhizoctonia-infected rice leaf sheaths revealed the presence of 16 proteins ranging from 20 to 90 kDa (approx.). Six were identified as constitutive defense proteins (increased after infection), 6 as secondary defense proteins (formed de novo) and the rest 4 appeared non-defense proteins. Non-inoculated kitazin-treated leaf sheaths showed 15 proteins of which 5 were constitutive and 4 secondary defense proteins (both are PR-proteins). Among the PR-proteins, five beta-1,3-glucanases and one chitinase was identified and characterized. One rice chitinase (MW 20 kDa) and 2 glucanases (60 & 69 kDa) showed serological relationships with tobacco chitinase (32 kDa) and tobacco glucanase (33 kDa) respectively. The implications of results have been discussed in relation to biotic and abiotic induction of PR-proteins in rice.
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Histidine residues in alpha-crystallin are not all available for chemical modification and acid-base titration. JOURNAL OF PROTEIN CHEMISTRY 1996; 15:585-90. [PMID: 8895105 DOI: 10.1007/bf01908540] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We have determined the number of histidine residues available for chemical modification with the specific reagent diethylpyrocarbonate in both bovine and goat alpha-crystallins. Results indicate that there are two distinctly different classes of histidine residues in the native protein. Out of 300 total histidine residues in the protein (on the basis of 800-kDa protein molecular weight) about 170 +/- 2 residues have been found to be modified by the reagent. The remaining 130 +/- 2 residues are modified when the protein is partially denatured in 1.5 M guanidine hydrochloride. The H(+)-titration behavior of the histidine residues in the protein corroborates this result. The observed differential accessibility of histidine residues may be important in maintaining the surface hydrophobicity of the aggregate as well as in stabilizing its quaternary structure.
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Does catheter traction reduce post-transurethral resection of the prostate blood loss? BRITISH JOURNAL OF UROLOGY 1995; 75:614-7. [PMID: 7613799 DOI: 10.1111/j.1464-410x.1995.tb07419.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To determine if traction on a catheter after transurethral resection of the prostate (TURP) reduces post-operative bleeding. PATIENTS AND METHODS This prospective trial included 115 consecutive patients undergoing TURP. After resection patients were randomly selected to have either traction (57) or no traction (58) on the catheter for 30 min. Blood loss was measured during and for 2 h after the operation. A simple method for applying constant traction is described. RESULTS Catheter traction reduced post-operative bleeding while applied, but had no further effect after the removal of traction. CONCLUSION Catheter traction is a useful technique to aid the control of post-TURP bleeding.
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Abstract
This article reports on the phenomenon of contagious hysteria in a village in West Bengal. The psychosocial and psychodynamic aspects are discussed.
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Molecular conformation and spectra of mesitil. Chem Phys Lett 1974. [DOI: 10.1016/0009-2614(74)87023-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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The pH of dental plaque and its relation to salivary pH and dental calculus. JOURNAL OF THE INDIAN DENTAL ASSOCIATION 1971; 43:28-36. [PMID: 5281320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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