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EXAMINATION OF THE INCIDENCE OF POOR SLEEP QUALITY AND FACTORS ASSOCIATED FOR POOR SLEEP DURING THE VARIOUS PHASES OF PREGNANCIES. GEORGIAN MEDICAL NEWS 2024:47-53. [PMID: 38609113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/14/2024]
Abstract
Objective - to measure poor sleep quality, its components, and the variables that contribute to it in a cohort of pregnant women across time. Four hundred and eighty-six strong singleton pregnancies were collected ahead of the fourteenth gestational week. Data on poor sleep quality were gathered before pregnancy and analyzed five distinct times in each trimester and six months after delivery. "Poor sleep quality (PSQ) was defined as a score of fewer than eight on the Athens Insomnia Scale (AIS), and for each trimester, adjusted odds ratios (aOR) with 95% confidence intervals (CI)"were acquired by use of multivariate logistic regression analysis. Pregnancy prevalence of poor SQ was 6.1 percent, followed by 44.2 percent in the first trimester (TR1), 46.3 percent in the second trimester (TR2), and 63.7 percent in the third trimester (TR3). Poor sleep quality after pregnancy was reported by 33.2 percent of women "(28.2-37.9) (p<0.001 for pre-gestational versus TR1, TR2 vs. TR3, and TR3 vs. post-pregnancy)."Due to a decrease in the quality of their nocturnal sleep, TR3's mean AIS score went from 2.34 before pregnant to 9.87; in contrast, TR1's detrimental impact on daytime functioning was larger. Poor sleep during the previous trimester was linked to poor sleep in TR2 and TR3. Poor SQ during pregnancy was a factor in TR1's poor SQ, and obesity was linked to bad sleep in TR3. The risks of having poor sleep quality in TR3 were instead decreased by moderate physical activity. Poor sleep throughout pregnancy was shown to be much more common than good sleep at any point in the pregnancy. In the latter stages of pregnancy, two out of every three expecting moms suffer poor SQ. Particular attention should be paid to pre-gestational poor SQ prevention and high body mass index.
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Dissolving Fusion Oncoprotein Condensates to Reverse Aberrant Gene Expression. Cancer Res 2023; 83:3324-3326. [PMID: 37828859 DOI: 10.1158/0008-5472.can-23-2769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 09/12/2023] [Indexed: 10/14/2023]
Abstract
In a recent study, Wang and colleagues reported that a significant fraction of cancer-associated fusion proteins display a common structural topology, including an N-terminal phase separation-prone region (PS) from one parent protein and a C-terminal DNA-binding domain (DBD) from the other. This is reminiscent of the structural topology of transcription factors and led to the hypothesis that the PS-DBD fusions form aberrant transcriptional condensates through phase separation, which was supported through transcriptomic data analysis and cellular condensate assays. The authors developed a high-throughput screen based upon time-lapse, high-content imaging to identify 114 compounds that dissolved condensates formed by a chromatin-dissociated mutant of FUS::ERG (FUS::ERGmut). One of these compounds, LY2835219, was shown to dissolve FUS::ERGmut condensates by promoting lysosome formation and was also active against condensates formed by other PS-DBD fusions, including EWS::FLI1. Finally, condensate dissolution by LY2835219 was shown to reverse aberrant gene expression driven by EWS::FLI1, although how this compound specifically marshals lysosomes to target some PS-DBD fusions and not other condensate-forming proteins remains elusive. This work not only highlights likely roles for aberrant condensate formation in the oncogenic function of PS-DBD fusions, but also provides proof of principle for mechanistically unbiased screening to identify compounds that modulate fusion protein-driven condensates and their oncogenic functions.
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Defining the condensate landscape of fusion oncoproteins. Nat Commun 2023; 14:6008. [PMID: 37770423 PMCID: PMC10539325 DOI: 10.1038/s41467-023-41655-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 09/13/2023] [Indexed: 09/30/2023] Open
Abstract
Fusion oncoproteins (FOs) arise from chromosomal translocations in ~17% of cancers and are often oncogenic drivers. Although some FOs can promote oncogenesis by undergoing liquid-liquid phase separation (LLPS) to form aberrant biomolecular condensates, the generality of this phenomenon is unknown. We explored this question by testing 166 FOs in HeLa cells and found that 58% formed condensates. The condensate-forming FOs displayed physicochemical features distinct from those of condensate-negative FOs and segregated into distinct feature-based groups that aligned with their sub-cellular localization and biological function. Using Machine Learning, we developed a predictor of FO condensation behavior, and discovered that 67% of ~3000 additional FOs likely form condensates, with 35% of those predicted to function by altering gene expression. 47% of the predicted condensate-negative FOs were associated with cell signaling functions, suggesting a functional dichotomy between condensate-positive and -negative FOs. Our Datasets and reagents are rich resources to interrogate FO condensation in the future.
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The Role of Phase-Separated Condensates in Fusion Oncoprotein–Driven Cancers. ANNUAL REVIEW OF CANCER BIOLOGY 2023. [DOI: 10.1146/annurev-cancerbio-061421-122050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Fusion oncoproteins (FOs) resulting from in-frame chromosomal translocations are associated with many aggressive cancers with poor patient outcomes. Several FOs are now understood to perform their oncogenic functions within biomolecular condensates formed through liquid-liquid phase separation (LLPS). Two classes of phase-separating FOs have emerged, those that form nuclear condensates and alter chromatin biology, including gene expression, and those that form cytoplasmic condensates and promote aberrant signaling, including RAS/MAPK signaling. The amino acid sequences of the FOs within these classes display LLPS-prone intrinsically disordered regions and folded domains that synergistically interact with themselves and other biomolecules to promote condensate formation. This review summarizes the roles of LLPS in the oncogenic functions of these two FO classes, provides examples of FOs that inhibit physiological LLPS in normal cells, and discusses the sequence features commonly associated with LLPS and their enrichment in many FOs. Expected final online publication date for the Annual Review of Cancer Biology, Volume 7 is April 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Understanding condensate formation by fusion oncoprotein-derived intrinsically disordered regions. Biophys J 2023; 122:345a. [PMID: 36783749 DOI: 10.1016/j.bpj.2022.11.1917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
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Charting the human disease condensate dysregulome. Dev Cell 2022; 57:1677-1679. [PMID: 35901780 DOI: 10.1016/j.devcel.2022.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Although it is understood that myriad proteins function in cells within biomolecular condensates, it is unclear how protein condensation is altered in human disease. In this issue of Developmental Cell, Banani et al. show that mutations in disease-associated proteins may map to phase-separation-prone regions and thereby alter condensate formation.
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Phase Separation Mediates NUP98 Fusion Oncoprotein Leukemic Transformation. Cancer Discov 2022; 12:1152-1169. [PMID: 34903620 PMCID: PMC8983581 DOI: 10.1158/2159-8290.cd-21-0674] [Citation(s) in RCA: 57] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 11/08/2021] [Accepted: 12/09/2021] [Indexed: 01/07/2023]
Abstract
NUP98 fusion oncoproteins (FO) are drivers in pediatric leukemias and many transform hematopoietic cells. Most NUP98 FOs harbor an intrinsically disordered region from NUP98 that is prone to liquid-liquid phase separation (LLPS) in vitro. A predominant class of NUP98 FOs, including NUP98-HOXA9 (NHA9), retains a DNA-binding homeodomain, whereas others harbor other types of DNA- or chromatin-binding domains. NUP98 FOs have long been known to form puncta, but long-standing questions are how nuclear puncta form and how they drive leukemogenesis. Here we studied NHA9 condensates and show that homotypic interactions and different types of heterotypic interactions are required to form nuclear puncta, which are associated with aberrant transcriptional activity and transformation of hematopoietic stem and progenitor cells. We also show that three additional leukemia-associated NUP98 FOs (NUP98-PRRX1, NUP98-KDM5A, and NUP98-LNP1) form nuclear puncta and transform hematopoietic cells. These findings indicate that LLPS is critical for leukemogenesis by NUP98 FOs. SIGNIFICANCE We show that homotypic and heterotypic mechanisms of LLPS control NUP98-HOXA9 puncta formation, modulating transcriptional activity and transforming hematopoietic cells. Importantly, these mechanisms are generalizable to other NUP98 FOs that share similar domain structures. These findings address long-standing questions on how nuclear puncta form and their link to leukemogenesis. This article is highlighted in the In This Issue feature, p. 873.
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Are fusion oncoproteins a source of disease-relevant, phase separation-prone protein regions? Biophys J 2022. [DOI: 10.1016/j.bpj.2021.11.1215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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The role of phase separation by NUP98 fusion oncoproteins in leukemia. Biophys J 2022. [DOI: 10.1016/j.bpj.2021.11.970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Ordered and Disordered Segments of Amyloid-β Drive Sequential Steps of the Toxic Pathway. ACS Chem Neurosci 2019; 10:2498-2509. [PMID: 30763064 DOI: 10.1021/acschemneuro.9b00015] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
While the roles of intrinsically disordered protein domains in driving interprotein interactions are increasingly well-appreciated, the mechanism of toxicity of disease-causing disordered proteins remains poorly understood. A prime example is Alzheimer's disease (AD) associated amyloid beta (Aβ). Aβ oligomers are highly toxic partially structured peptide assemblies with a distinct ordered region (residues ∼10-40) and a shorter disordered region (residues ∼1-9). Here, we investigate the role of this disordered domain and its relation to the ordered domain in the manifestation of toxicity through a set of Aβ fragments and stereoisomers designed for this purpose. We measure their effects on lipid membranes and cultured neurons, probing their toxicity, intracellular distributions, and specific molecular interactions using the techniques of confocal imaging, lattice light sheet imaging, fluorescence lifetime imaging, and fluorescence correlation spectroscopy. Remarkably, we find that neither part-Aβ10-40 or Aβ1-9, is toxic by itself. The ordered part (Aβ10-40) is the major determinant of how Aβ attaches to lipid bilayers, enters neuronal cells, and localizes primarily in the late endosomal compartments. However, once Aβ enters the cell, it is the disordered part (only when it is connected to the rest of the peptide) that has a strong and stereospecific interaction with an unknown cellular component, as demonstrated by distinct changes in the fluorescence lifetime of a fluorophore attached to the N-terminal. This interaction appears to commit Aβ to the toxic pathway. Our findings correlate well with Aβ sites of familial AD mutations, a significant fraction of which cluster in the disordered region. We conclude that, while the ordered region dictates attachment and cellular entry, the key to toxicity lies in the ordered part presenting the disordered part for a specific cellular interaction.
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Ordered and Disordered Segments of Amyloid‐β Drive Sequential Steps of the Toxic Pathway. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.lb203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Methods for Physical Characterization of Phase-Separated Bodies and Membrane-less Organelles. J Mol Biol 2018; 430:4773-4805. [PMID: 30017918 PMCID: PMC6503534 DOI: 10.1016/j.jmb.2018.07.006] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 07/04/2018] [Accepted: 07/09/2018] [Indexed: 12/17/2022]
Abstract
Membrane-less organelles are cellular structures which arise through the phenomenon of phase separation. This process enables compartmentalization of specific sets of macromolecules (e.g., proteins, nucleic acids), thereby regulating cellular processes by increasing local concentration, and modulating the structure and dynamics of their constituents. Understanding the connection between structure, material properties and function of membrane-less organelles requires inter-disciplinary approaches, which address length and timescales that span several orders of magnitude (e.g., Ångstroms to micrometer, picoseconds to hours). In this review, we discuss the wide variety of methods that have been applied to characterize the morphology, rheology, structure and dynamics of membrane-less organelles and their components, in vitro and in live cells.
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Aggregation-induced conformation changes dictate islet amyloid polypeptide (IAPP) membrane affinity. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1734-1740. [DOI: 10.1016/j.bbamem.2018.03.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/20/2018] [Accepted: 03/21/2018] [Indexed: 11/30/2022]
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Understanding the underlying motives and intention among Indian blood donors towards voluntary blood donation: A cross-sectional study. Transfus Clin Biol 2018; 25:109-117. [PMID: 29472138 DOI: 10.1016/j.tracli.2018.01.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 01/24/2018] [Indexed: 11/19/2022]
Abstract
OBJECTIVES The present study aims to fill the gap in the literature by conducting a comprehensive research on Indian donor's intention towards voluntary blood donation in India. The study attempts to conceptualize and validate an integrative framework incorporating voluntary function inventory (VFI) in the theory of planned behaviour (TPB) model with the purpose tomeasure the voluntary blood donation intention. MATERIAL AND METHODS Structural equation modeling (SEM) has been used to rigorously test the hypothesized interrelationships among the underlying motives influencing voluntary blood donation intention. A self-administered questionnaire was used to collect data from a sample of respondents selected conveniently from selct locations in India. Total 450 completed questionnaires were received out of 1000 distributed. RESULTS The study develops a final conceptual framework that determines the drivers of blood donor's intention towards voluntary donation. The components of theory of planned behavior (TPB) model which include 'attitude', 'subjective norms' (SN), and 'perceived behavioral control' (PBC) along with modified volunteer functions namely 'value', 'social', 'career' and 'enhancement' were found significantly explaining the donation intention in the model. CONCLUSION The model achieves robustness with respect to predicting Indian donor's intention towards the voluntary donation of blood. The proposed model in this study advances the theory and research on thevolunteering motives towards blood donation. The study would provide a comprehensiveunderstanding of donors' intention to the practitioners, policy makers and Non-Government Organization (NGO), helping them to frame a calibrated strategydirected towards facilitating healthy blood donation practices.
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Fluorescence quenching by lipid encased nanoparticles shows that amyloid-β has a preferred orientation in the membrane. Chem Commun (Camb) 2018; 54:7750-7753. [DOI: 10.1039/c8cc02108b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Short range plasmonic fields around a nanoparticle can modulate fluorescence or Raman processes.
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Perturbation of the F19-L34 Contact in Amyloid β (1-40) Fibrils Induces Only Local Structural Changes but Abolishes Cytotoxicity. J Phys Chem Lett 2017; 8:4740-4745. [PMID: 28910107 DOI: 10.1021/acs.jpclett.7b02317] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We explored structural details of fibrils formed by a mutated amyloid β (Aβ(1-40)) peptide carrying a Phe19 to Lys19 mutation, which was shown to completely abolish the toxicity of the molecule. Computer models suggest that the positively charged Lys19 side chain is expelled from the hydrophobic fibril interior upon fibrillation. This can be accommodated by either a 180° flip of the entire lower β-strand (model M1) or local perturbations of the secondary structure in the direct vicinity of the mutated site (model M2). This is accompanied by the formation of a new salt bridge between Glu22 and Lys28 in model M1. Experimentally, a novel contact between Phe20 and Leu34 as well as the significant structural perturbation of residues 20-23 could be confirmed. However, the mutated fibrils do not show the formation of any salt bridges. This demonstrates that although morphologically very robust, local perturbations of the Aβ(1-40) sequence lead to moderate structural alterations with tremendous impact on the physiological importance of these aggregates, which may suggest alternative strategies for the development of a remedy against Alzheimer's disease.
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Curcumin Dictates Divergent Fates for the Central Salt Bridges in Amyloid-β 40 and Amyloid-β 42. Biophys J 2017; 112:1597-1608. [PMID: 28445751 DOI: 10.1016/j.bpj.2017.02.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 02/02/2017] [Accepted: 02/07/2017] [Indexed: 12/25/2022] Open
Abstract
There are three specific regions in the Amyloid beta (Aβ) peptide sequence where variations cause enhanced toxicity in Alzheimer's disease: the N-terminus, the central salt bridge, and the C-terminus. Here, we investigate if there is a close conformational connection between these three regions, which may suggest a concerted mechanism of toxicity. We measure the effects of Zn2+ and curcumin on Aβ40, and compare these with their previously reported effects on Aβ42. Aβ42 and Aβ40 differ only near the C-terminus, where curcumin interacts, while Zn2+ interacts near the N-terminus. Therefore, this comparison should help us differentiate the effect of modulating the C- and the N-termini. We find that curcumin allows fibril-like structures containing the salt bridge to emerge in the mature Aβ40 aggregates, but not in Aβ42. In contrast, we find no difference in the effects of Zn+2 on Aβ40 and Aβ42. In the presence of Zn+2, both of these fail to form proper fibrils, and the salt bridge remains disrupted. These results indicate that modulations of the Aβ termini can determine the fate of a salt bridge far away in the sequence, and this has significant consequences for Aβ toxicity. We also infer that small molecules can alter oligomer-induced toxicity by modulating the aggregation pathway, without substantially changing the final product of aggregation.
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Emerging structural details of transient amyloid-β oligomers suggest designs for effective small molecule modulators. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.02.070] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Abstract
Shape complementarity between close-packed residues plays a critical role in the amyloid aggregation process. Here, we probe such "steric zipper" interactions in amyloid-β (Aβ40), whose aggregation is linked to Alzheimer's disease, by replacing natural residues by their stereoisomers. Such mutations are expected to specifically destabilize the shape sensitive "packing" interactions, which may potentially increase their solubility and change other properties. We study the stereomutants DF19 and DL34 and also the DA2/DF4/DH6/DS8 mutant of Aβ40. F19-L34 is a critical contact in a tightly packed region of Aβ, while residues 1-9 are known to be disordered. While both DF19 and DL34 slow down the kinetics of aggregation and form amyloid fibrils efficiently, only DL34 increases the final solubility. DF19 gives rise to additional off-pathway aggregation which results in large, kinetically stable aggregates, and has lower net solubility. DA2/DF4/DH6/DS8 does not have an effect on the kinetics or the solubility. Notably, both DF19 and DL34 oligomers have a significantly lower level of interactions with lipid vesicles and live cells. We conclude that stereoisomers can cause complex site dependent changes in amyloid properties, and provide an effective tool to determine the role of individual residues in shaping the packed interiors of amyloid aggregates.
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Aggregation Induced Conformation Changes Determine Amylin Membrane Affinity. Biophys J 2017. [DOI: 10.1016/j.bpj.2016.11.1960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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A Hidden Structural Transition Accompanies the Progression of Amyloid-Beta Oligomers to Mature Fibrils. Biophys J 2016. [DOI: 10.1016/j.bpj.2015.11.1928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Enhanced two photon absorption cross section and optical nonlinearity of a quasi-octupolar molecule. J Photochem Photobiol A Chem 2016. [DOI: 10.1016/j.jphotochem.2015.08.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Cell-Membrane-Mimicking Lipid-Coated Nanoparticles Confer Raman Enhancement to Membrane Proteins and Reveal Membrane-Attached Amyloid-β Conformation. ACS NANO 2015; 9:9070-7. [PMID: 26391443 DOI: 10.1021/acsnano.5b03175] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Identifying the structures of membrane bound proteins is critical to understanding their function in healthy and diseased states. We introduce a surface enhanced Raman spectroscopy technique which can determine the conformation of membrane-bound proteins, at low micromolar concentrations, and also in the presence of a substantial membrane-free fraction. Unlike conventional surface enhanced Raman spectroscopy, our approach does not require immobilization of molecules, as it uses spontaneous binding of proteins to lipid bilayer-encapsulated Ag nanoparticles. We apply this technique to probe membrane-attached oligomers of Amyloid-β40 (Aβ40), whose conformation is keenly sought in the context of Alzheimer's disease. Isotope-shifts in the Raman spectra help us obtain secondary structure information at the level of individual residues. Our results show the presence of a β-turn, flanked by two β-sheet regions. We use solid-state NMR data to confirm the presence of the β-sheets in these regions. In the membrane-attached oligomer, we find a strongly contrasting and near-orthogonal orientation of the backbone H-bonds compared to what is found in the mature, less-toxic Aβ fibrils. Significantly, this allows a "porin" like β-barrel structure, providing a structural basis for proposed mechanisms of Aβ oligomer toxicity.
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Do evidence practice gaps exist for medication prescription at hospital discharge in patients undergoing coronary artery bypass and coronary angioplasty. Indian Heart J 2014. [DOI: 10.1016/j.ihj.2014.10.331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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A framework of intelligent decision support system for Indian police. JOURNAL OF ENTERPRISE INFORMATION MANAGEMENT 2014. [DOI: 10.1108/jeim-10-2012-0073] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Purpose
– The purpose of this paper is to introduce architecture of an Intelligent Decision Support System to fulfill the emerging responsibilities of law enforcement agencies.
Design/methodology/approach
– The proposed Intelligent Police System (IPS) is designed to meet the emerging requirements and provide information at all levels of decision making by introducing a multi-level structure of user interface and crime analysis model. The proposed framework of IPS is based on data mining and performance measurement techniques to extract useful information like crime hot spots, predict crime trends and rank police administration units on the basis of crime prevention measures.
Findings
– IPS has been implemented on actual Indian crime data provided by National Crime Records Bureau (NCRB), which illustrates effectiveness and usefulness of the proposed system. IPS can play a vital role in improving outcome in the crime investigation, criminal detection and other major areas of functioning of police organization by analyzing the crime data and sharing of the information.
Research limitations/implications
– The research in intelligent police information system can be enhanced with some important additional features which include web-base management system, geographical information system, mobile adhoc network technology, etc.
Practical implications
– IPS can easily be applied to any police system in the world and can equally be useful for any law enforcement agencies for carrying out homeland security effectively.
Originality/value
– The research reported in this manuscript is outcome of the research project funded by NCRB. This paper is the first attempt to build framework of IPS for Indian police who deal with large volume and high rate of crimes that are unmatched to any police force of the world.
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Inside Cover: Significant Structural Differences between Transient Amyloid-β Oligomers and Less-Toxic Fibrils in Regions Known To Harbor Familial Alzheimer′s Mutations (Angew. Chem. Int. Ed. 27/2014). Angew Chem Int Ed Engl 2014. [DOI: 10.1002/anie.201405438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Innentitelbild: Significant Structural Differences between Transient Amyloid-β Oligomers and Less-Toxic Fibrils in Regions Known To Harbor Familial Alzheimer′s Mutations (Angew. Chem. 27/2014). Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201405438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Design of heat shock-resistant surfaces to prevent protein aggregation: Enhanced chaperone activity of immobilized α-Crystallin. Bioconjug Chem 2014; 25:888-95. [PMID: 24689782 DOI: 10.1021/bc500097q] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
α-Crystallin is a multimeric protein belonging to the family of small heat shock proteins, which function as molecular chaperones by resisting heat and oxidative stress induced aggregation of other proteins. We immobilized α-Crystallin on a self-assembled monolayer on glass surface and studied its activity in terms of the prevention of aggregation of aldolase. We discovered that playing with grafted protein density led to interesting variations in the chaperone activity of immobilized α-Crystallin. This result is in accordance with the hypothesis that dynamicity of subunits plays a vital role in the functioning of α-Crystallin and might be able to throw light on the structure-activity relationship. We showed that the chaperone activity of a certain number of immobilized α-Crystallins was superior compared to a solution containing an equivalent number of the protein and 10 times the number of the protein at temperatures >60 °C. The α-Crystallin grafted surfaces retained activity on reuse. This could also lead to the design of potent heat-shock resistant surfaces that can find wide applications in storage and shipping of protein based biopharmaceuticals.
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Significant Structural Differences between Transient Amyloid-β Oligomers and Less-Toxic Fibrils in Regions Known To Harbor Familial Alzheimer′s Mutations. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201402636] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Significant structural differences between transient amyloid-β oligomers and less-toxic fibrils in regions known to harbor familial Alzheimer's mutations. Angew Chem Int Ed Engl 2014; 53:6888-92. [PMID: 24756858 DOI: 10.1002/anie.201402636] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Indexed: 11/11/2022]
Abstract
Small oligomers of the amyloid β (Aβ) peptide, rather than the monomers or the fibrils, are suspected to initiate Alzheimer's disease (AD). However, their low concentration and transient nature under physiological conditions have made structural investigations difficult. A method for addressing such problems has been developed by combining rapid fluorescence techniques with slower two-dimensional solid-state NMR methods. The smallest Aβ40 oligomers that demonstrate a potential sign of toxicity, namely, an enhanced affinity for cell membranes, were thus probed. The two hydrophobic regions (residues 10-21 and 30-40) have already attained the conformation that is observed in the fibrils. However, the turn region (residues 22-29) and the N-terminal tail (residues 1-9) are strikingly different. Notably, ten of eleven known Aβ mutants that are linked to familial AD map to these two regions. Our results provide potential structural cues for AD therapeutics and also suggest a general method for determining transient protein structures.
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Structure of the Transient, Membrane-Active Amyloid Beta Oligomers in Physiological Solutions Probed by a Combination of Fluorescence and Solid State NMR. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.1577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Solvatochromism, multiphoton fluorescence, and resonance energy transfer in a new octupolar dye-pair. Chem Phys 2013. [DOI: 10.1016/j.chemphys.2013.01.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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1.311 A NOVEL CASE OF RESTLESS LEG SYNDROME (RLS) DUE TO INTRACEREBRAL HAEMORRHAGE. Parkinsonism Relat Disord 2012. [DOI: 10.1016/s1353-8020(11)70369-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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An efficient statistical feature selection approach for classification of gene expression data. J Biomed Inform 2011; 44:529-35. [PMID: 21241823 DOI: 10.1016/j.jbi.2011.01.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 11/16/2010] [Accepted: 01/03/2011] [Indexed: 10/18/2022]
Abstract
Classification of gene expression data plays a significant role in prediction and diagnosis of diseases. Gene expression data has a special characteristic that there is a mismatch in gene dimension as opposed to sample dimension. All genes do not contribute for efficient classification of samples. A robust feature selection algorithm is required to identify the important genes which help in classifying the samples efficiently. In order to select informative genes (features) based on relevance and redundancy characteristics, many feature selection algorithms have been introduced in the past. Most of the earlier algorithms require computationally expensive search strategy to find an optimal feature subset. Existing feature selection methods are also sensitive to the evaluation measures. The paper introduces a novel and efficient feature selection approach based on statistically defined effective range of features for every class termed as ERGS (Effective Range based Gene Selection). The basic principle behind ERGS is that higher weight is given to the feature that discriminates the classes clearly. Experimental results on well-known gene expression datasets illustrate the effectiveness of the proposed approach. Two popular classifiers viz. Nave Bayes Classifier (NBC) and Support Vector Machine (SVM) have been used for classification. The proposed feature selection algorithm can be helpful in ranking the genes and also is capable of identifying the most relevant genes responsible for diseases like leukemia, colon tumor, lung cancer, diffuse large B-cell lymphoma (DLBCL), prostate cancer.
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A New Selection Measure for Classification Using Decision Trees. JOURNAL OF INFORMATION & KNOWLEDGE MANAGEMENT 2004. [DOI: 10.1142/s0219649204000626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The paper proposes a new selection measure for classification using decision trees for Data mining. Various algorithms have been proposed in the past for classification using decision trees viz. ID3, CART, SLIQ, etc. Selection measures like the Gain, Gain ratio, and Gini index have been proposed in these algorithms. However, none of the selection measures developed so far take into account the balancing of trees. This paper proposes a new selection measure which also takes into account the balancing of trees that will facilitate in improving the classification accuracy. The performance of the original SLIQ algorithm, C5 and the algorithm using the new selection measure (which takes into account the accuracy as well as the balance factor) was measured on the basis of the classification accuracy. Three real life data sets were chosen for this purpose.
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Aesthetic evolution and its infusion in consumer durable. JOURNAL OF ADVANCES IN MANAGEMENT RESEARCH 2003. [DOI: 10.1108/97279810380000360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This paper explores some aspects of aesthetics, its qualities and attributes in case of a consumer durable and the association of some attributes and quality with one another. Attempt is also made to understand the extent to which these play a role in designing a consumer durable. The attribute beauty, quality, feel and experience emerged important, whereas in the case of qualities of aesthetics beauty, order and symmetry, definitions, form proportion, finishing and unity of various parts emerged important. Amongst attributes, feel and experience has the highest association with other attributes of aesthetics. The correlation between qualities of aesthetics established that there is association between all the qualities of aesthetics, which confirms interrelationship with each other.
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Abstract
BACKGROUND Esophageal carcinoma is one of the most lethal tumors. Therefore, it is important to identify prognostic factors for patients with this disease. The objective of this study was to clarify the relation between clinicopathologic and biologic factors in esophageal carcinoma and to determine the prognostic significance of different biologic factors. METHODS DNA ploidy pattern, Ki-67 labeling index (LI), and cyclin D1 and p53 protein expression were examined and detailed pathologic examinations were conducted on tumors from 53 patients (46 males and 7 females with a mean age of 66 years [range, 47-85 years]) with surgically resected esophageal squamous cell carcinoma and the prognostic value of these factors was evaluated. RESULTS Of the 53 esophagus carcinomas examined, 26 (49%) were classified as DNA diploid. The mean Ki-67 LI was 45 +/- 4. 9% (range, 10.5-86.1%). p53 expression was detected in 38 of the carcinomas (71.7%) and cyclin D1 expression was detected in 35 (66%). Various prognostic factors were examined using the Cox stepwise regression model, four of which were found to correlate with overall survival: tumor size (P = 0.0346), lymph node status (P = 0.0384), Ki-67 LI (P = 0.0161), and p53 expression (P = 0.001). Lower Ki-67 LI and a lower rate of p53 expression were detected in the long term survival group (> 3 years) compared with the short term survival group (P = 0.00045 and P = 0.0023, respectively). CONCLUSIONS The biologic factors of Ki-67 LI and p53 expression, as well as clinicopathologic factors, may be used as independent prognostic factors for patients with esophageal carcinoma. However, the results of the current study do not support cyclin D1 expression as a prognostic factor.
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Abstract
BACKGROUND Esophageal carcinoma is one of the most lethal tumors. Therefore, it is important to identify prognostic factors for patients with this disease. The objective of this study was to clarify the relation between clinicopathologic and biologic factors in esophageal carcinoma and to determine the prognostic significance of different biologic factors. METHODS DNA ploidy pattern, Ki-67 labeling index (LI), and cyclin D1 and p53 protein expression were examined and detailed pathologic examinations were conducted on tumors from 53 patients (46 males and 7 females with a mean age of 66 years [range, 47-85 years]) with surgically resected esophageal squamous cell carcinoma and the prognostic value of these factors was evaluated. RESULTS Of the 53 esophagus carcinomas examined, 26 (49%) were classified as DNA diploid. The mean Ki-67 LI was 45 +/- 4. 9% (range, 10.5-86.1%). p53 expression was detected in 38 of the carcinomas (71.7%) and cyclin D1 expression was detected in 35 (66%). Various prognostic factors were examined using the Cox stepwise regression model, four of which were found to correlate with overall survival: tumor size (P = 0.0346), lymph node status (P = 0.0384), Ki-67 LI (P = 0.0161), and p53 expression (P = 0.001). Lower Ki-67 LI and a lower rate of p53 expression were detected in the long term survival group (> 3 years) compared with the short term survival group (P = 0.00045 and P = 0.0023, respectively). CONCLUSIONS The biologic factors of Ki-67 LI and p53 expression, as well as clinicopathologic factors, may be used as independent prognostic factors for patients with esophageal carcinoma. However, the results of the current study do not support cyclin D1 expression as a prognostic factor.
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