1
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Sahoo BR, Subramanian V, Bardwell JCA. Backbone 1H, 13C, and 15N chemical shift assignments for human SERF2. Biomol NMR Assign 2024; 18:51-57. [PMID: 38466543 DOI: 10.1007/s12104-024-10167-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 02/28/2024] [Indexed: 03/13/2024]
Abstract
Human small EDRK-rich factor protein SERF2 is a cellular driver of protein amyloid formation, a process that has been linked to neurodegenerative diseases including Alzheimer's and Parkinson's disease. SERF2 is a 59 amino acid protein, highly charged, and well conserved whose structure and physiological function is unclear. SERF family proteins including human SERF2 have shown a tendency to form fuzzy complexes with misfolded proteins such as α-Synuclein which has been linked to Parkinson's disease. SERF family proteins have been recently identified to bind nucleic acids, but the binding mechanism(s) remain enigmatic. Here, using multidimensional solution NMR, we report the 1H, 15N, and 13C chemical shift assignments (~ 86% of backbone resonance assignments) for human SERF2. TALOS-N predicted secondary structure of SERF2 showed three very short helices (3-4 residues long) in the N-terminal region of the protein and a long helix in the C-terminal region spanning residues 37-46 which is consistent with the helical content indicated by circular dichroism spectroscopy. Paramagnetic relaxation enhancement NMR analysis revealed that a short C-terminal region E53-K55 is in the proximity of the N-terminus. Having the backbone assignment of SERF2 allowed us to probe its interaction with α-Synuclein and to identify the residues in SERF2 binding interfaces that likely promote α-Synuclein aggregation.
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Affiliation(s)
- Bikash R Sahoo
- Howard Hughes Medical Institute, Chevy Chase, MD-20815, USA.
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI-48109, USA.
| | | | - James C A Bardwell
- Howard Hughes Medical Institute, Chevy Chase, MD-20815, USA
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI-48109, USA
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2
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Priyadarsinee L, Jamir E, Nagamani S, Mahanta HJ, Kumar N, John L, Sarma H, Kumar A, Gaur AS, Sahoo R, Vaikundamani S, Murugan NA, Priyakumar UD, Raghava GPS, Bharatam PV, Parthasarathi R, Subramanian V, Sastry GM, Sastry GN. Molecular Property Diagnostic Suite for COVID-19 (MPDS COVID-19): an open-source disease-specific drug discovery portal. GigaByte 2024; 2024:gigabyte114. [PMID: 38525218 PMCID: PMC10958779 DOI: 10.46471/gigabyte.114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 03/11/2024] [Indexed: 03/26/2024] Open
Abstract
Molecular Property Diagnostic Suite (MPDS) was conceived and developed as an open-source disease-specific web portal based on Galaxy. MPDSCOVID-19 was developed for COVID-19 as a one-stop solution for drug discovery research. Galaxy platforms enable the creation of customized workflows connecting various modules in the web server. The architecture of MPDSCOVID-19 effectively employs Galaxy v22.04 features, which are ported on CentOS 7.8 and Python 3.7. MPDSCOVID-19 provides significant updates and the addition of several new tools updated after six years. Tools developed by our group in Perl/Python and open-source tools are collated and integrated into MPDSCOVID-19 using XML scripts. Our MPDS suite aims to facilitate transparent and open innovation. This approach significantly helps bring inclusiveness in the community while promoting free access and participation in software development. Availability & Implementation The MPDSCOVID-19 portal can be accessed at https://mpds.neist.res.in:8085/.
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Affiliation(s)
- Lipsa Priyadarsinee
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Esther Jamir
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
| | - Selvaraman Nagamani
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Hridoy Jyoti Mahanta
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Nandan Kumar
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
| | - Lijo John
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
| | - Himakshi Sarma
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
| | - Asheesh Kumar
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
| | - Anamika Singh Gaur
- CSIR-Indian Institute of Toxicology Research, Lucknow, 226001, Uttar Pradesh, India
| | - Rosaleen Sahoo
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - S. Vaikundamani
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
| | - N. Arul Murugan
- Indraprastha Institute of Information Technology, Delhi, 110020, India
| | - U. Deva Priyakumar
- International Institute of Information Technology, Gachibowli, Hyderabad, 500032, India
| | - G. P. S. Raghava
- Indraprastha Institute of Information Technology, Delhi, 110020, India
| | - Prasad V. Bharatam
- National Institute of Pharmaceutical Education and Research, S.A.S. Nagar (Mohali), 160062, India
| | - Ramakrishnan Parthasarathi
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- CSIR-Indian Institute of Toxicology Research, Lucknow, 226001, Uttar Pradesh, India
| | - V. Subramanian
- Department of Chemistry, Indian Institute of Technology, Chennai, 600036, India
| | - G. Madhavi Sastry
- Schrödinger Inc., Octave, Salarpuria Sattva Knowledge City, 1st Floor, Unit 3A, Hyderabad, 500081, India
| | - G. Narahari Sastry
- CSIR–North East Institute of Science and Technology, Jorhat, 785006, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- Indian Institute of Technology (IIT) Hyderabad, Kandi, Sangareddy, Telangana, 502284, India
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3
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Darthy RR, Venkateswaran C, Subramanian V, Ouyang Z, Yogesh N. Accessing new avenues of photonic bandgaps using two-dimensional non-Moiré geometries. Sci Rep 2023; 13:17077. [PMID: 37816847 PMCID: PMC10564743 DOI: 10.1038/s41598-023-44385-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 10/07/2023] [Indexed: 10/12/2023] Open
Abstract
Photonic crystals (PhC) formed by 2-D non-Moiré geometries are realized in this work. Non-Moiré (NM) tiles are the contours of trigonometric functions that generate exciting shapes and geometries. Photonic bandstructure calculations reveal that 2-D NM geometries exhibit new avenues of photonic bandgaps compared to the regular circular rod-based PhCs. The band structures are anisotropic and show, intriguing orientation-dependent partial bandgaps. A few of the orientation-dependent frequency selective properties of the realized NM geometry-based PhCs are demonstrated using full-wave electromagnetic simulations. The proposed geometries are practically realizable, and in this work, we experimentally demonstrate the fabrication process using the 3-D printing technique for microwave frequencies.
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Affiliation(s)
- R Rachel Darthy
- Department of Nuclear Physics, School of Physical Sciences, University of Madras, Chennai, 600025, India
| | - C Venkateswaran
- Department of Nuclear Physics, School of Physical Sciences, University of Madras, Chennai, 600025, India
| | - V Subramanian
- Microwave Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Zhengbiao Ouyang
- Terahertz Technical Research Center, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - N Yogesh
- Department of Physics, National Institute of Technology Calicut, Kozhikode, 673601, Kerala, India.
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4
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Dahal A, Subramanian V, Shrestha P, Liu D, Gauthier T, Jois S. Conformationally constrained cyclic grafted peptidomimetics targeting protein-protein interactions. Pept Sci (Hoboken) 2023; 115:e24328. [PMID: 38188985 PMCID: PMC10769001 DOI: 10.1002/pep2.24328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 07/03/2023] [Indexed: 01/09/2024]
Abstract
Sunflower trypsin inhibitor-1 (SFTI-1) structure is used for designing grafted peptides as a possible therapeutic agent. The grafted peptide exhibits multiple conformations in solution due to the presence of proline in the structure of the peptide. To lock the grafted peptide into a major conformation in solution, a dibenzofuran moiety (DBF) was incorporated in the peptide backbone structure, replacing the Pro-Pro sequence. NMR studies indicated a major conformation of the grafted peptide in solution. Detailed structural studies suggested that SFTI-DBF adopts a twisted beta-strand structure in solution. The surface plasmon resonance analysis showed that SFTI-DBF binds to CD58 protein. A model for the protein-SFTI-DBF complex was proposed based on docking studies. These studies suggested that SFTI-1 grafted peptide can be used to design stable peptides for therapeutic purposes by grafting organic functional groups and amino acids. However, when a similar strategy was used with another grafted peptide, the resulting peptide did not produce a single major conformation, and its biological activity was lost. Thus, conformational constraints depend on the sequence of amino acids used for SFTI-1 grafting.
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Affiliation(s)
- Achyut Dahal
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe LA 71201
| | - Vivekanandan Subramanian
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536
| | - Prajesh Shrestha
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe LA 71201
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803
| | - Dong Liu
- AgCenter Biotechnology Laboratory, LSU Agricultural Center, Baton Rouge, LA, 70803
| | - Ted Gauthier
- AgCenter Biotechnology Laboratory, LSU Agricultural Center, Baton Rouge, LA, 70803
| | - Seetharama Jois
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, Monroe LA 71201
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803
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5
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Bhosale SS, Mandal A, Hou C, McCorkle JR, Schweer D, Hill KS, Subramanian V, Kolesar JM, Tsodikov OV, Rohr J. Mithplatins: Mithramycin SA-Pt(II) Complex Conjugates for the Treatment of Platinum-Resistant Ovarian Cancers. ChemMedChem 2023; 18:e202200368. [PMID: 36342449 PMCID: PMC9899322 DOI: 10.1002/cmdc.202200368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 11/04/2022] [Indexed: 11/09/2022]
Abstract
DNA coordinating platinum (Pt) containing compounds cisplatin and carboplatin have been used for the treatment of ovarian cancer therapy for four decades. However, recurrent Pt-resistant cancers are a major cause of mortality. To combat Pt-resistant ovarian cancers, we designed and synthesized a conjugate of an anticancer drug mithramycin with a reactive Pt(II) bearing moiety, which we termed mithplatin. The conjugates displayed both the Mg2+ -dependent noncovalent DNA binding characteristic of mithramycin and the covalent crosslinking to DNA of the Pt. The conjugate was three times as potent as cisplatin against ovarian cancer cells. The DNA lesions caused by the conjugate led to the generation of DNA double-strand breaks, as also observed with cisplatin. Nevertheless, the conjugate was highly active against both Pt-sensitive and Pt-resistant ovarian cancer cells. This study paves the way to developing mithplatins to combat Pt-resistant ovarian cancers.
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Affiliation(s)
- Suhas S Bhosale
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone Street, Lexington, KY, 40536, USA
| | - Abhisek Mandal
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone Street, Lexington, KY, 40536, USA
| | - Caixia Hou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone Street, Lexington, KY, 40536, USA
| | - J Robert McCorkle
- Markey Cancer Center, University of Kentucky, 760 S. Rose Street, Lexington, KY, 40536, USA
| | - David Schweer
- Division of Gynecologic Oncology, College of Medicine, 760 S. Rose Street, Lexington, KY, 40536, USA
| | - Kristen S Hill
- Markey Cancer Center, University of Kentucky, 760 S. Rose Street, Lexington, KY, 40536, USA
| | - Vivekanandan Subramanian
- University of Kentucky PharmNMR Center, College of Pharmacy, University of Kentucky, Lexington, KY, 40536-0596, USA
| | - Jill M Kolesar
- Markey Cancer Center, University of Kentucky, 760 S. Rose Street, Lexington, KY, 40536, USA
- Division of Gynecologic Oncology, College of Medicine, 760 S. Rose Street, Lexington, KY, 40536, USA
- Department of Pharmacy Practice and Science, College of Pharmacy, University of Kentucky, 760 Press Avenue, Lexington, KY, 40536, USA
| | - Oleg V Tsodikov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone Street, Lexington, KY, 40536, USA
| | - Jürgen Rohr
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone Street, Lexington, KY, 40536, USA
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6
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Subramanian V, Segar M, Wang TW, Pandey AP. Hemodynamics of acute decompensated heart failure in patients with very low NP levels. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background/Introduction
Natriuretic Peptides are hormones secreted by the heart in response to cardiomyocyte stretch. The principal biological action of NP is natriuresis, diuresis and vasodilation. These are salutary effects in acute decompensated heart failure (ADHF). Some patients admitted with ADHF have very low NP levels. It is unknown if this is due to a defect in biosynthesis or inadequate stimulation.
Purpose
We analyzed data from the National heart Lung and Blood institute sponsored ESCAPE trial which included patients admitted with acute decompensated heart failure who underwent hemodynamic assessment with pulmonary artery catheters at admission and after diuresis. Our aim was to evaluate if there were characteristic hemodynamic findings among patients with very low NP levels at admission which differed from those who had elevated NP levels at admission.
Methods
We performed a secondary analysis of the ESCAPE Trial. We defined very low BNP as patients with BNP level at admission <50 pg/mL. We then compared baseline characteristics between the groups. Continuous groups were compared using X-square test, and Categorical variables were compared using Wilcoxon-signed-Rank-Sum test. We compared groups by Demographic, Anthropometric, Laboratory, and Functional status. We then performed propensity matching on Age, Sex, and BMI and then compared groups.
Results
25/351 patients had very low BNP (<50pg/mL). Patients in the low BNP group had higher BMI than those with elevated BNP (35.8 vs. 28.9 p<0.001). The cohort with low BNP was younger. (50.2 vs. 56.4 p=0.029). In propensity matched cohorts of Age, Sex, BMI. Cardiac output was elevated in the low BNP cohort. (5.2 vs. 3.9 p=0.011). However, Cardiac Index was similar between the groups (2.2 vs. 2.0 p=0.244). Patients in the Low NP group had lower pulmonary capillary wedge pressure (PCWP) compared to those with elevated BNP. (16.5 vs. 25.4 p=0.023). The groups had similar RA pressures (11.5 vs. 13.0 p=0.515). The calculated transmural pressure (PCWP – RA pressure) was lower in the low NP group. There was a reduction in BNP levels at discharge among the group with elevated BNP at admission (1072.6 (baseline) 798.8 (discharge)) In the low BNP group there was an increase in BNP at time of discharge (20.2 (baseline) to 172.7 (discharge)). In follow-up, the low BNP group had reduction in BNP compared to their discharge levels. The group with elevated BNP had elevated BNP at follow-up in 3 and 6 months. Length of stay was shorter in the Low BNP group (6.2 vs. 8.8, p=0.052).
Conclusion(s)
In this secondary analysis of the ESCAPE trial, we find that those patients admitted with ADHF who have unexpectedly low BNP have lower transmural pressures at baseline compared to those who have elevated BNP levels. This suggests that there may not be adequate stimulus for cardiac wall distention and release of BNP.
Funding Acknowledgement
Type of funding sources: None.
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Affiliation(s)
- V Subramanian
- UT Southwestern Medical Center , Dallas , United States of America
| | - M Segar
- Texas Heart Institute, Cardiology , Houston , United States of America
| | - T W Wang
- UT Southwestern Medical Center , Dallas , United States of America
| | - A P Pandey
- UT Southwestern Medical Center , Dallas , United States of America
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7
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Kumar MC, Sudha AJ, Subramanian V, Athmalingam S, Venkatraman B. Effect of Internal Decay Power and Surface Cooling on Nuclear Fuel Droplet Solidification during MFCI in a SFR – A Numerical Study. NUCL SCI ENG 2022. [DOI: 10.1080/00295639.2022.2103338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Affiliation(s)
- M. Chandra Kumar
- Indira Gandhi Centre for Atomic Research, Constituent Institution of Homi Bhabha National Institute, Kalpakkam 603102, India
| | - A. Jasmin Sudha
- Indira Gandhi Centre for Atomic Research, Constituent Institution of Homi Bhabha National Institute, Kalpakkam 603102, India
- Indira Gandhi Centre for Atomic Research, Safety, Quality and Resource Management Group, Kalpakkam 603102, India
| | - V. Subramanian
- Indira Gandhi Centre for Atomic Research, Safety, Quality and Resource Management Group, Kalpakkam 603102, India
| | - S. Athmalingam
- Indira Gandhi Centre for Atomic Research, Safety, Quality and Resource Management Group, Kalpakkam 603102, India
| | - B. Venkatraman
- Indira Gandhi Centre for Atomic Research, Safety, Quality and Resource Management Group, Kalpakkam 603102, India
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8
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Behnsen J, Zhi H, Aron AT, Subramanian V, Santus W, Lee MH, Gerner RR, Petras D, Liu JZ, Green KD, Price SL, Camacho J, Hillman H, Tjokrosurjo J, Montaldo NP, Hoover EM, Treacy-Abarca S, Gilston BA, Skaar EP, Chazin WJ, Garneau-Tsodikova S, Lawrenz MB, Perry RD, Nuccio SP, Dorrestein PC, Raffatellu M. Siderophore-mediated zinc acquisition enhances enterobacterial colonization of the inflamed gut. Nat Commun 2021; 12:7016. [PMID: 34853318 PMCID: PMC8636617 DOI: 10.1038/s41467-021-27297-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 11/09/2021] [Indexed: 11/09/2022] Open
Abstract
Zinc is an essential cofactor for bacterial metabolism, and many Enterobacteriaceae express the zinc transporters ZnuABC and ZupT to acquire this metal in the host. However, the probiotic bacterium Escherichia coli Nissle 1917 (or "Nissle") exhibits appreciable growth in zinc-limited media even when these transporters are deleted. Here, we show that Nissle utilizes the siderophore yersiniabactin as a zincophore, enabling Nissle to grow in zinc-limited media, to tolerate calprotectin-mediated zinc sequestration, and to thrive in the inflamed gut. We also show that yersiniabactin's affinity for iron or zinc changes in a pH-dependent manner, with increased relative zinc binding as the pH increases. Thus, our results indicate that siderophore metal affinity can be influenced by the local environment and reveal a mechanism of zinc acquisition available to commensal and pathogenic Enterobacteriaceae.
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Affiliation(s)
- Judith Behnsen
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
- Department of Microbiology & Immunology, University of Illinois Chicago, Chicago, IL, USA
| | - Hui Zhi
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Allegra T Aron
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
- Collaborative Mass Spectrometry Innovation Center, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Vivekanandan Subramanian
- University of Kentucky PharmNMR Center, College of Pharmacy, University of Kentucky, Lexington, KY, 40536-0596, USA
| | - William Santus
- Department of Microbiology & Immunology, University of Illinois Chicago, Chicago, IL, USA
| | - Michael H Lee
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Romana R Gerner
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Daniel Petras
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
- Collaborative Mass Spectrometry Innovation Center, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Janet Z Liu
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
| | - Keith D Green
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, 40536-0596, USA
| | - Sarah L Price
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Jose Camacho
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Hannah Hillman
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Joshua Tjokrosurjo
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
| | - Nicola P Montaldo
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
| | - Evelyn M Hoover
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
| | - Sean Treacy-Abarca
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
| | - Benjamin A Gilston
- Department of Biochemistry and Chemistry, and Center for Structural Biology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Eric P Skaar
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Walter J Chazin
- Department of Biochemistry and Chemistry, and Center for Structural Biology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sylvie Garneau-Tsodikova
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, 40536-0596, USA
| | - Matthew B Lawrenz
- Center for Predictive Medicine for Biodefense and Emerging Infectious Diseases, Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Robert D Perry
- Department of Microbiology and Immunology, University of Kentucky, Lexington, KY, 40536, USA
| | - Sean-Paul Nuccio
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
| | - Pieter C Dorrestein
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
- Collaborative Mass Spectrometry Innovation Center, University of California, San Diego, La Jolla, CA, 92093, USA
- Center for Microbiome Innovation, University of California San Diego, La Jolla, CA, 92093, USA
| | - Manuela Raffatellu
- Department of Microbiology & Molecular Genetics, University of California Irvine, Irvine, CA, USA.
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA.
- Center for Microbiome Innovation, University of California San Diego, La Jolla, CA, 92093, USA.
- Chiba University-UC San Diego Center for Mucosal Immunology, Allergy, and Vaccines (CU-UCSD cMAV), La Jolla, CA, 92093, USA.
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9
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Panigrahi S, Mohanty AK, Samantara MK, Sahu G, Chandrasekaran S, Subramanian V, Srinivas CV. Distribution, annual committed effective dose, and health safety assessment of 210Po in marine biota from Kalpakkam coast, Bay of Bengal. Mar Pollut Bull 2021; 173:113147. [PMID: 34808544 DOI: 10.1016/j.marpolbul.2021.113147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 06/13/2023]
Abstract
Seafood, intertidal biota, beach sediment, and seawater from Kalpakkam coast, Bay of Bengal were analyzed for 210Po to evaluate the internal exposure and other radiological safety aspects. Kalpakkam houses various nuclear power generation facilities on its coast. The activity concentration of 210Po was more pronounced in the intertidal organisms. Pelagic planktivorous fishes have the highest activity of the non-technogenic radionuclide, followed by the detrital feeders, benthic planktivores, benthic carnivores, and pelagic carnivore fishes. The affinity of 210Po to organic detrital matter and planktonic organisms has led to a higher accumulation of radionuclide in planktivorous fishes. Activity concentration of 210Po in seafood ranged between 1.13 ± 0.3 and 96.71 ± 1.6 Bq kg-1 (Becquerel/kilogram). In seaweeds and gastropods, it ranged from 2.09 ± 0.2 to 8.21 ± 0.6 and from 9.31 ± 0.7 to 21.58 ± 1.2 Bq kg-1, respectively. The committed effective dose (CED) of 210Po in seafood varied from 31.18 to 456.68 μSv yr-1 (microSievert/year). Radiological hazard parameters, such as activity intake, CED in consumption, of the seafood from this coast are within the acceptable levels prescribed by the International Commission on Radiological Protection and US Environmental Protection Agency.
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Affiliation(s)
- Satyanarayan Panigrahi
- Environmental Assessment Section, EAD/RESG/SQRMG, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu 603 102, India.
| | - A K Mohanty
- Aerosol Transport and Biodiversity Section, RESD/RESG/SQRMG, Indira Gandhi Centre for Atomic Research, Kalpakkam, India
| | - M K Samantara
- Aerosol Transport and Biodiversity Section, RESD/RESG/SQRMG, Indira Gandhi Centre for Atomic Research, Kalpakkam, India
| | - G Sahu
- Aerosol Transport and Biodiversity Section, RESD/RESG/SQRMG, Indira Gandhi Centre for Atomic Research, Kalpakkam, India
| | - S Chandrasekaran
- Environmental Assessment Section, EAD/RESG/SQRMG, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu 603 102, India; Homi Bhaba National Institute, Anushakti Nagar, Mumbai, India
| | - V Subramanian
- Aerosol Transport and Biodiversity Section, RESD/RESG/SQRMG, Indira Gandhi Centre for Atomic Research, Kalpakkam, India
| | - C V Srinivas
- Environmental Assessment Section, EAD/RESG/SQRMG, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu 603 102, India; Homi Bhaba National Institute, Anushakti Nagar, Mumbai, India
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10
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Danish JS, Vasanth P, Subramanian V. Prevalence of Intestinal Parasitic Infestations among Children in a Tertiary Care Centre. JPRI 2021. [DOI: 10.9734/jpri/2021/v33i47b33197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Introduction: Intestinal parasitic infestations are more common in developing countries and an important cause of morbidity in pediatric age group. It causes abdominal pain, diarrhoea, anemia, impaired cognitive function, growth retardation and poor academic performance among school going children.
Objectives: To analyze age, gender and most common parasitic infestations among children in a tertiary care hospital in south India.
Materials and Methods: Stool samples of pediatric patients in a tertiary care hospital is analysed for a period of one year for detection of prevalence of parasitic infestations.
Results: In our study, 115 stool samples were analysed and prevalence of intestinal parasitic infections was found to be 7.82% (9/115).There were five different parasites encountered. The most common parasite identified was Giardia lamblia(4/9)(44.44%) followed by Entamoeba histolytica(2/9)(22.22%), Ascarislumbricoides(1/9)(11.11%), Trichuris trichiura(1/9)(11.11%), and Hymenolepis nana(1/9)(11.11%).
Conclusion: Giardia lamblia and Entamoeba histolytica were found to be the most common organism in our study. Awareness about proper hygiene, sanitation and prophylactic anti-protozoal medications is important to prevent the occurrence and complications of intestinal parasitic infestations.
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11
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Chitra N, Sundar SB, Valan II, Subramanian V, Jose MT, Venkatraman B. MODELING AND EXPERIMENTS TO ESTIMATE RADON EMANATION FACTOR IN SOIL-GRAIN SIZE AND MOISTURE EFFECT. Radiat Prot Dosimetry 2021; 194:104-112. [PMID: 34132341 DOI: 10.1093/rpd/ncab087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/05/2021] [Accepted: 05/19/2021] [Indexed: 06/12/2023]
Abstract
The influence of soil grain size on its radon emanation mechanism was investigated by developing a Monte-Carlo model. The proposed model supplements the previous formulations by accounting for the effect elicited by specific surface area of the sample. The specific surface area of a sample is governed by its grain size and it strongly influences the emanation rate which is a surface phenomenon. The emanation study was further extended to include the moisture effect. Experiments were carried out with two soil samples; Soil-2 and Soil-4 collected from different terrains, to analyze the role played by moisture in the emanation mechanism. The above model was augmented with provisions to include the moisture input. The model could reproduce the experimental results. There is an abrupt increase in the emanation factor when the moisture content changes from 0 to 2%. Thereafter, the increase is gradual and finally becomes steady when the moisture level reaches 10%. Soil-2 and Soil-4 showed sizeable difference in their radon emanation factor values. This could be explained based on the parent226Ra distribution pattern which stems from the mineralogical composition of the samples. Quartz was predominantly found in Soil-2, whereas Soil-4 shows peaks corresponding to minerals namely ilmenite, Rutile and Zircon confirming relatively higher concentration of heavy minerals than Soil-2. The emanation factor values of the individual minerals reported in the literature were used to decide upon the 226Ra distribution depth and with this input the model to ascertain the experimental observations.
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Affiliation(s)
- N Chitra
- Radiological and Environmental Safety Division, Kalpakkam 603102, Tamilnadu, India
- Homi Bhabha National Institute, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamilnadu, India
| | - S Bala Sundar
- Radiological and Environmental Safety Division, Kalpakkam 603102, Tamilnadu, India
| | - I Inigo Valan
- Radiological and Environmental Safety Division, Kalpakkam 603102, Tamilnadu, India
| | - V Subramanian
- Radiological and Environmental Safety Division, Kalpakkam 603102, Tamilnadu, India
- Homi Bhabha National Institute, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamilnadu, India
| | - M T Jose
- Radiological and Environmental Safety Division, Kalpakkam 603102, Tamilnadu, India
- Homi Bhabha National Institute, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamilnadu, India
| | - B Venkatraman
- Radiological and Environmental Safety Division, Kalpakkam 603102, Tamilnadu, India
- Homi Bhabha National Institute, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamilnadu, India
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12
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Arun B, Viswanathan S, Subramanian V, Jose MT, Venkatraman B. Study of Triple to Double Coincidence Method for Tritium Measurements. Radiochemistry 2021. [DOI: 10.1134/s1066362221020120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Balasundar S, Chandrasekaran S, Subramanian V, Venkatraman B. Investigations on neutron attenuation properties of poly-boron materials using Am-Be and 252Cf sources neutron spectra. ANN NUCL ENERGY 2021. [DOI: 10.1016/j.anucene.2020.108083] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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14
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Kumaran R, Kumar AV, Ramaprabhu S, Subramanian V. Absorption-enhanced EMI shielding using silver decorated three-dimensional porous architected reduced graphene oxide in polybenzoxazine composites. NEW J CHEM 2021. [DOI: 10.1039/d1nj03536c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The proliferation of wearable and portable electronic media has increased the demand for highly efficient materials that can be used to create shields against electromagnetic interference.
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Affiliation(s)
- R. Kumaran
- Microwave Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai, Tamil Nadu-600036, India
| | - A. Vinaya Kumar
- Microwave Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai, Tamil Nadu-600036, India
| | - S. Ramaprabhu
- Alternative Energy and Nanotechnology Laboratory (AENL), Department of Physics, Indian Institute of Technology Madras, Chennai, Tamil Nadu-600036, India
| | - V. Subramanian
- Microwave Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai, Tamil Nadu-600036, India
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15
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Ghai V, Subramanian V, Jan H, Pergialiotis V, Thakar R, Doumouchtsis SK. A systematic review on reported outcomes and outcome measures in female idiopathic chronic pelvic pain for the development of a core outcome set. BJOG 2020; 128:628-634. [PMID: 32654406 DOI: 10.1111/1471-0528.16412] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/29/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND A core outcome set (COS) is required to address inconsistencies in outcome reporting in chronic pelvic pain (CPP) trials. OBJECTIVES Evaluation of reported outcomes and selected outcome measures in CPP trials by producing a comprehensive inventory to inform a COS. SEARCH STRATEGY Systematic review of randomised controlled trials (RCTs) identified from Cochrane Central Register of Controlled Trials (CENTRAL), Embase and MEDLINE databases. SELECTION CRITERIA RCTs assessing efficacy and safety of medical, surgical and psychological interventions for women with idiopathic CPP. DATA COLLECTION AND ANALYSIS Two independent researchers extracted outcomes and outcome measures. Similar outcomes were grouped and classified into domains to produce a structured inventory. MAIN RESULTS Twenty-four trials were identified including 136 reported outcomes and outcome measures. Rates of reporting outcomes varied (4-100%) and pelvic pain was the most frequently reported outcome (100%). All trials reported the pain domain; however, only half reported quality of life, clinical effectiveness and adverse events. No differences in outcome reporting were observed in five high-quality trials (21%). Univariate analysis demonstrated an association between quality of outcome reporting and methodological quality of studies (rs = 0.407, P = 0.048). CONCLUSION There is wide variation in reported outcomes and applied outcome measures in CPP trials. While a COS is being developed and implemented, we propose the interim use of commonly reported outcomes in each domain: pain (pelvic pain, dyspareunia, dysmenorrhoea), life impact (quality of life, emotional functioning, physical functioning), clinical effectiveness (efficacy, satisfaction, cost effectiveness, return to daily activities) and adverse events (surgical, perioperative observations, nonsurgical). TWEETABLE ABSTRACT There is significant variation in outcome reporting in CPP trials. Our systematic review forms the basis for the development of a core outcome set.
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Affiliation(s)
- V Ghai
- Department of Obstetrics and Gynaecology, Epsom & St Helier University Hospitals NHS Trust, London, UK.,St George's University of London, London, UK
| | - V Subramanian
- Department of Obstetrics and Gynaecology, Epsom & St Helier University Hospitals NHS Trust, London, UK
| | - H Jan
- Department of Obstetrics and Gynaecology, Epsom & St Helier University Hospitals NHS Trust, London, UK
| | - V Pergialiotis
- Laboratory of Experimental Surgery and Surgical Research N.S. Christeas, Athens University Medical School, Athens, Greece
| | - R Thakar
- Department of Urogynaecology, Croydon University Hospital NHS Trust, London, UK
| | - S K Doumouchtsis
- Department of Obstetrics and Gynaecology, Epsom & St Helier University Hospitals NHS Trust, London, UK.,St George's University of London, London, UK.,Laboratory of Experimental Surgery and Surgical Research N.S. Christeas, Athens University Medical School, Athens, Greece.,American University of the Caribbean, School of Medicine, Pembroke Pines, FL, USA
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16
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Sviripa VM, Fiandalo MV, Begley KL, Wyrebek P, Kril LM, Balia AG, Parkin SR, Subramanian V, Chen X, Williams AH, Zhan CG, Liu C, Mohler JL, Watt DS. Pictet-Spengler condensations using 4-(2-aminoethyl)coumarins. NEW J CHEM 2020; 44:13415-13429. [PMID: 33795928 DOI: 10.1039/d0nj02664f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Androgen-deprivation therapy (ADT) is only a palliative measure, and prostate cancer invariably recurs in a lethal, castration-resistant form (CRPC). Prostate cancer resists ADT by metabolizing weak, adrenal androgens to growth-promoting 5α-dihydrotestosterone (DHT), the preferred ligand for the androgen receptor (AR). Developing small-molecule inhibitors for the final steps in androgen metabolic pathways that utilize 17-oxidoreductases required probes that possess fluorescent groups at C-3 and intact, naturally occurring functionality at C-17. Application of the Pictet-Spengler condensation to substituted 4-(2-aminoethyl)coumarins and 5α-androstane-3-ones furnished spirocyclic, fluorescent androgens at the desired C-3 position. Condensations required the presence of activating C-7 amino or N,N-dialkylamino groups in the 4-(2-aminoethyl)coumarin component of these condensation reactions. Successful Pictet-Spengler condensation, for example, of DHT with 9-(2-aminoethyl)-2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-11-one led to a spirocyclic androgen, (3R,5S,10S,13S,17S)-17-hydroxy-10,13-dimethyl-1,2,2',3',4,5,6,7,8,8',9,9',10,11,12,12',13,13',14,15,16,17-docosahydro-7'H,11'H-spiro-[cyclopenta[a]phenanthrene-3,4'-pyrido[3,2,1-ij]pyrido[4',3':4,5]pyrano[2,3-f]quinolin]-5'(1'H)-one. Computational modeling supported the surrogacy of the C-3 fluorescent DHT analog as a tool to study 17-oxidoreductases for intracrine, androgen metabolism.
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Affiliation(s)
- Vitaliy M Sviripa
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596 USA.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596 USA.,Lucille Parker Markey Cancer Center, University of Kentucky, Lexington, KY 40536-0093 USA
| | - Michael V Fiandalo
- Department of Experimental Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, NY 14263 USA
| | - Kristin L Begley
- Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596 USA.,Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509 USA
| | - Przemyslaw Wyrebek
- Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596 USA.,Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509 USA
| | - Liliia M Kril
- Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596 USA.,Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509 USA
| | - Andrii G Balia
- Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596 USA.,Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509 USA
| | - Sean R Parkin
- Department of Chemistry, College of Arts and Sciences, University of Kentucky, Lexington, KY 40506 USA
| | | | - Xi Chen
- College of Chemistry and Material Science, South Central University for Nationalities, Wuhan 430074, People's Republic of China
| | - Alexander H Williams
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596 USA
| | - Chang-Guo Zhan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596 USA.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596 USA
| | - Chunming Liu
- Lucille Parker Markey Cancer Center, University of Kentucky, Lexington, KY 40536-0093 USA.,Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509 USA
| | - James L Mohler
- Department of Experimental Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, NY 14263 USA.,Department of Urology, Roswell Park Comprehensive Cancer Center, Buffalo, NY 14263 USA
| | - David S Watt
- Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0596 USA.,Lucille Parker Markey Cancer Center, University of Kentucky, Lexington, KY 40536-0093 USA.,Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky, Lexington, KY 40536-0509 USA
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17
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Chitra N, Sundar SB, Subramanian V, Jose MT, Baskaran R, Venkatraman B. QUANTIFICATION OF BACK DIFFUSION IN RADON AND THORON EXHALATION RATE MEASUREMENTS. Radiat Prot Dosimetry 2020; 189:182-189. [PMID: 32239152 DOI: 10.1093/rpd/ncaa029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 01/16/2020] [Accepted: 02/14/2020] [Indexed: 06/11/2023]
Abstract
The radon (222Rn) and thoron (220Rn) fluxes from the soil and building materials are the major contributors to their indoor levels. Hence, the measurement of radon and thoron exhalation rates from the source matrix becomes the foremost step in controlling the indoor radon and thoron exposure. It is a challenge to measure the exhalation rates without disturbing the natural conditions. The back-diffusion phenomenon modifies the exhalation rate. The work presented here is to measure the back-diffusion coefficient and takes it into consideration while estimating the exhalation rate. For radon measurements, the back-diffusion coefficient and the free exhalation rates were simultaneously estimated by adopting a novel methodology. The leak rate of the experimental setup measured by this methodology was agreeable with the value measured by adopting the standard technique. In the case of thoron, the back-diffusion effect was found to be negligible for the present experimental conditions and it is duly explained. The above results were obtained by analyzing two soil samples with high 238U and 232Th content collected from monazite-rich coastal area.
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Affiliation(s)
- N Chitra
- Radiological and Environmental Safety Division, Indira Gandhi Center for Atomic Research, Kalpakkam, Tamilnadu, India
- Homi Bhabha National Institute, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamilnadu, India
| | - S Bala Sundar
- Radiological and Environmental Safety Division, Indira Gandhi Center for Atomic Research, Kalpakkam, Tamilnadu, India
| | - V Subramanian
- Radiological and Environmental Safety Division, Indira Gandhi Center for Atomic Research, Kalpakkam, Tamilnadu, India
- Homi Bhabha National Institute, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamilnadu, India
| | - M T Jose
- Radiological and Environmental Safety Division, Indira Gandhi Center for Atomic Research, Kalpakkam, Tamilnadu, India
- Homi Bhabha National Institute, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamilnadu, India
| | - R Baskaran
- Radiological and Environmental Safety Division, Indira Gandhi Center for Atomic Research, Kalpakkam, Tamilnadu, India
- Homi Bhabha National Institute, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamilnadu, India
| | - B Venkatraman
- Radiological and Environmental Safety Division, Indira Gandhi Center for Atomic Research, Kalpakkam, Tamilnadu, India
- Homi Bhabha National Institute, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamilnadu, India
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18
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Darthy RR, Venkateswaran C, Subramanian V, Ouyang Z, Yogesh N. Fabry-Pérot modes associated with hyperbolic-like dispersion in dielectric photonic crystals and demonstration of a bending angle sensor at microwave frequencies. Sci Rep 2020; 10:11117. [PMID: 32632230 PMCID: PMC7338461 DOI: 10.1038/s41598-020-67965-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 06/04/2020] [Indexed: 11/09/2022] Open
Abstract
The dispersion properties of metamaterials and photonic crystals (PhCs) lead to an intensive research in the development of cavity resonators for the confinement of electromagnetic (e-m) radiation. In this work, we investigate the formation of Fabry-Pérot (FP) modes associated with hyperbolic-like dispersion (HLD) regimes in two-dimensional dielectric PhCs. Conventionally, FP modes are formed using an optical etalon, in which electromagnetic (e-m) waves reflecting from a partially reflecting mirror separated by a distance can interfere constructively and form a resonating mode. The FP mode observed in dielectric PhCs is formed due to the interference of cylindrical wavefronts inside the PhC interface at HLD frequencies. The FP modes in PhCs are surface localized, in which maxima/minima of the electric field lies along the air-PhC interface as a standing wave pattern and decays in air medium. Projected bandstructure, Eigen Frequency Contours (EFC), phase and group index calculations are carried out to explain the formation of FP modes in PhCs under different coupling cases. By varying the PhC dimension, FP modes with different spatial profiles are witnessed and the role of source position in exciting specific mode is demonstrated. The observed FP modes in PhCs are compared with the FP mode in an ideal indefinite slab. Based on the FP resonance in PhCs, a sensing device capable of detecting a bending angle less than [Formula: see text] is demonstrated numerically. The FP modes in PhCs are scalable to other parts of e-m spectra so that the bending angle sensing can be extendable to terahertz and optical domains.
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Affiliation(s)
- R Rachel Darthy
- Department of Nuclear Physics, School of Physical Sciences, University of Madras, Chennai, 600025, India
| | - C Venkateswaran
- Department of Nuclear Physics, School of Physical Sciences, University of Madras, Chennai, 600025, India
| | - V Subramanian
- Microwave Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India
| | - Zhengbiao Ouyang
- Terahertz Technical Research Center, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - N Yogesh
- Department of Nuclear Physics, School of Physical Sciences, University of Madras, Chennai, 600025, India.
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19
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Kumar A, Subramanian V, K. Velaga S, Kodandaraman J, Sujatha PN, Baskaran R, Kumar S, Ananda Rao B. Performance evaluation of a tubular bowl centrifuge by using laser obscuration method as an online measurement tool. SEP SCI TECHNOL 2020. [DOI: 10.1080/01496395.2019.1611853] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Amit Kumar
- Radiological & Environmental Safety Division, Indira Gandhi Centre for Atomic Research , Kalpakkam, India
| | - V. Subramanian
- Radiological & Environmental Safety Division, Indira Gandhi Centre for Atomic Research , Kalpakkam, India
| | - Satish K. Velaga
- Reprocessing Group, Indira Gandhi Centre for Atomic Research , Kalpakkam, India
| | - J. Kodandaraman
- Reprocessing Group, Indira Gandhi Centre for Atomic Research , Kalpakkam, India
| | | | - R. Baskaran
- Radiological & Environmental Safety Division, Indira Gandhi Centre for Atomic Research , Kalpakkam, India
| | - Shekhar Kumar
- Reprocessing Group, Indira Gandhi Centre for Atomic Research , Kalpakkam, India
| | - B.M. Ananda Rao
- Reprocessing Group, Indira Gandhi Centre for Atomic Research , Kalpakkam, India
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20
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Amaljith CK, Venkateswaran C, Subramanian V, Ouyang Z, Yogesh N. Anisotropic asymmetric transmission of circularly polarized terahertz waves in a three-dimensional spline assembly. Opt Lett 2020; 45:2315-2318. [PMID: 32287222 DOI: 10.1364/ol.388646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 03/06/2020] [Indexed: 06/11/2023]
Abstract
Asymmetric transmission (AT) for circularly polarized (CP) electromagnetic (e-m) waves in chiral metamaterial (CMM) is a well-known phenomenon. However, most of the CMMs exhibit AT along only one direction. In this work, AT for CP waves with a magnitude of more than 0.5 along three principal directions of a newly made three-dimensional (3D) spline assembly is reported at terahertz frequencies. Surface current analysis is presented to explain the mechanism of AT for CP waves in the proposed 3D assembly.
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21
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Navaratna T, Atangcho L, Mahajan M, Subramanian V, Case M, Min A, Tresnak D, Thurber GM. Directed Evolution Using Stabilized Bacterial Peptide Display. J Am Chem Soc 2020; 142:1882-1894. [PMID: 31880439 DOI: 10.1021/jacs.9b10716] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Chemically stabilized peptides have attracted intense interest by academics and pharmaceutical companies due to their potential to hit currently "undruggable" targets. However, engineering an optimal sequence, stabilizing linker location, and physicochemical properties is a slow and arduous process. By pairing non-natural amino acid incorporation and cell surface click chemistry in bacteria with high-throughput sorting, we developed a method to quantitatively select high affinity ligands and applied the Stabilized Peptide Evolution by E. coli Display technique to develop disrupters of the therapeutically relevant MDM2-p53 interface. Through in situ stabilization on the bacterial surface, we demonstrate rapid isolation of stabilized peptides with improved affinity and novel structures. Several peptides evolved a second loop including one sequence (Kd = 1.8 nM) containing an i, i+4 disulfide bond. NMR structural determination indicated a bent helix in solution and bound to MDM2. The bicyclic peptide had improved protease stability, and we demonstrated that protease resistance could be measured both on the bacterial surface and in solution, enabling the method to test and/or screen for additional drug-like properties critical for biologically active compounds.
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Affiliation(s)
- Tejas Navaratna
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Lydia Atangcho
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Mukesh Mahajan
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | | | - Marshall Case
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Andrew Min
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Daniel Tresnak
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Greg M Thurber
- Department of Chemical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States.,Department of Biomedical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
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22
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Sarkar D, Chakraborty I, Condorelli M, Ghosh B, Mass T, Weingarth M, Mandal AK, La Rosa C, Subramanian V, Bhunia A. Self‐Assembly and Neurotoxicity of β‐Amyloid (21–40) Peptide Fragment: The Regulatory Role of GxxxG Motifs. ChemMedChem 2019; 15:293-301. [DOI: 10.1002/cmdc.201900620] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 11/19/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Dibakar Sarkar
- Department of Biophysics Bose Institute P-1/12 CIT Scheme VII (M) Kolkata 700054 India
| | - Ipsita Chakraborty
- Department of Biophysics Bose Institute P-1/12 CIT Scheme VII (M) Kolkata 700054 India
| | | | - Baijayanti Ghosh
- Division of Molecular Medicine Bose Institute P-1/12 CIT Scheme VII (M) Kolkata 700054 India
| | - Thorben Mass
- Department of Chemistry Utrecht University Padualaan 8 3584 Utrecht The Netherlands
| | - Markus Weingarth
- Department of Chemistry Utrecht University Padualaan 8 3584 Utrecht The Netherlands
| | - Atin K Mandal
- Division of Molecular Medicine Bose Institute P-1/12 CIT Scheme VII (M) Kolkata 700054 India
| | - Carmelo La Rosa
- Department of Chemical Sciences University of Catania 95125 Catania Italy
| | | | - Anirban Bhunia
- Department of Biophysics Bose Institute P-1/12 CIT Scheme VII (M) Kolkata 700054 India
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Bramha SN, Krishnan H, Subramanian V, Baskaran R, Venkatraman B. BASELINE EVALUATION STUDY OF NATURALLY OCCURRING RADIONUCLIDES IN SOIL SAMPLES FROM VICINITY OF INDIA'S FIRST FAST REACTOR FUEL CYCLE FACILITY (FRFCF), DAE COMPLEX, KALPAKKAM, INDIA. Radiat Prot Dosimetry 2019; 185:87-95. [PMID: 30561717 DOI: 10.1093/rpd/ncy262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 11/21/2018] [Indexed: 06/09/2023]
Abstract
The activity concentration of 238U, 232Th and 40K were measured in the soil samples collected from Fast Reactor Fuel Cycle Facility (FRFCF) site, using high-resolution gamma-ray spectrometry. This study is aimed to establish the baseline data of naturally occurring radionuclides within the site. The average activity concentrations were found to be 416.5, 61.7 and 622.3 Bq kg-1 for 40K, 238U and 232Th, respectively. The activity concentrations and its radiological indices were evaluated and were compared with the international values reported by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The ratio of 40K/232Th and 40K /238U were calculated, which indicates the presence of 5.79 and 2.69 times more K-bearing minerals as compared with Th and U-bearing minerals in the soil samples, respectively. The study provides baseline information on concentration of radionuclides and background radiological assessment of the FRFCF site.
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Affiliation(s)
- S N Bramha
- Health, Safety and Environment Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu, India
| | - H Krishnan
- Health, Safety and Environment Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu, India
| | - V Subramanian
- Health, Safety and Environment Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu, India
| | - R Baskaran
- Health, Safety and Environment Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu, India
| | - B Venkatraman
- Health, Safety and Environment Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu, India
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Stephen L, Yogesh N, Subramanian V. Realization of Bidirectional, Bandwidth-Enhanced Metamaterial Absorber for Microwave Applications. Sci Rep 2019; 9:10058. [PMID: 31296915 PMCID: PMC6624316 DOI: 10.1038/s41598-019-46464-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 06/25/2019] [Indexed: 11/23/2022] Open
Abstract
The ever-increasing interest towards metamaterial absorbers owes to its remarkable features such as ultra-thin nature and design flexibility. Subduing the inherent narrow bandwidth of such absorbers is the prime goal in metamaterial absorber research, as this can widen the applications areas. A greater challenge is to construct bidirectional absorber, which provides direction-insensitive absorption, as most of the existing designs exhibit single sided absorption due to the complete metal film used in the design. This work presents the realization of a bidirectional, bandwidth-enhanced metamaterial absorber with basic elements such as strips and squares optimized to have adjacent resonances leading to a bandwidth-enhanced absorption. The structural evolution of the constituent metallic components towards the formation of bandwidth-enhanced absorption is described. The bidirectional absorber exhibits more than 90% absorption between 13.40 GHz and 14.25 GHz from the two incident directions. The mechanism of absorption is studied with the surface current analysis and the effective parameters of the structure. The choice of the metallic components with four-fold rotation symmetry renders the proposed design to be polarization independent and wide-angle receptive. The numerical studies are verified experimentally at microwave frequencies, which shows a good agreement between them.
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Affiliation(s)
- Lincy Stephen
- Microwave Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India
| | - N Yogesh
- Department of Nuclear Physics, School of Physical Sciences, University of Madras, Chennai, 600025, India
| | - V Subramanian
- Microwave Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai, 600036, India.
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25
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Kim S, Graham MJ, Lee RG, Yang L, Kim S, Subramanian V, Layne JD, Cai L, Temel RE, Shih D, Lusis AJ, Berliner JA, Lee S. Heparin-binding EGF-like growth factor (HB-EGF) antisense oligonucleotide protected against hyperlipidemia-associated atherosclerosis. Nutr Metab Cardiovasc Dis 2019; 29:306-315. [PMID: 30738642 PMCID: PMC6452438 DOI: 10.1016/j.numecd.2018.12.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 11/24/2018] [Accepted: 12/27/2018] [Indexed: 01/08/2023]
Abstract
BACKGROUND AND AIMS Heparin-binding EGF-like growth factor (HB-EGF) is a representative EGF family member that interacts with EGFR under diverse stress environment. Previously, we reported that the HB-EGF-targeting using antisense oligonucleotide (ASO) effectively suppressed an aortic aneurysm in the vessel wall and circulatory lipid levels. In this study, we further examined the effects of the HB-EGF ASO administration on the development of hyperlipidemia-associated atherosclerosis using an atherogenic mouse model. METHODS AND RESULTS The male and female LDLR deficient mice under Western diet containing 21% fat and 0.2% cholesterol content were cotreated with control and HB-EGF ASOs for 12 weeks. We observed that the HB-EGF ASO administration effectively downregulated circulatory VLDL- and LDL-associated lipid levels in circulation; concordantly, the HB-EGF targeting effectively suppressed the development of atherosclerosis in the aorta. An EGFR blocker BIBX1382 administration suppressed the hepatic TG secretion rate, suggesting a positive role of the HB-EGF signaling for the hepatic VLDL production. We newly observed that there was a significant improvement of the insulin sensitivity by the HB-EGF ASO administration in a mouse model under the Western diet as demonstrated by the improvement of the glucose and insulin tolerances. CONCLUSION The HB-EGF ASO administration effectively downregulated circulatory lipid levels by suppressing hepatic VLDL production rate, which leads to effective protection against atherosclerosis in the vascular wall.
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Affiliation(s)
- S Kim
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, 40536, USA
| | - M J Graham
- Cardiovascular Antisense Drug Discovery Group, Ionis Pharmaceuticals, Carlsbad, CA, 92010, USA
| | - R G Lee
- Cardiovascular Antisense Drug Discovery Group, Ionis Pharmaceuticals, Carlsbad, CA, 92010, USA
| | - L Yang
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, 40536, USA
| | - S Kim
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, 40536, USA
| | - V Subramanian
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, 40536, USA; Department of Physiology, University of Kentucky, Lexington, KY, 40536, USA
| | - J D Layne
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, 40536, USA
| | - L Cai
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, 40536, USA
| | - R E Temel
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, 40536, USA; Department of Physiology, University of Kentucky, Lexington, KY, 40536, USA
| | - D Shih
- Department of Medicine-Cardiology, University of California-Los Angeles (UCLA) School of Medicine, Los Angeles, CA, 90095, USA
| | - A J Lusis
- Department of Medicine-Cardiology, University of California-Los Angeles (UCLA) School of Medicine, Los Angeles, CA, 90095, USA; Department of Human Genetics, University of California-Los Angeles (UCLA) School of Medicine, Los Angeles, CA, 90095, USA; Department of Microbiology, Immunology & Molecular Genetics, University of California-Los Angeles (UCLA), Los Angeles, CA, 90095, USA
| | - J A Berliner
- Department of Pathology and Laboratory Medicine, University of California-Los Angeles (UCLA), Los Angeles, CA, 90095, USA
| | - S Lee
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, 40536, USA; Department of Pharmacology & Nutritional Sciences, University of Kentucky, Lexington, KY, 40536, USA.
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Vijaya sundar J, Subramanian V, Rajakumar B. Excited state C–N bond dissociation and cyclization of tri-aryl amine-based OLED materials: a theoretical investigation. Phys Chem Chem Phys 2019; 21:438-447. [DOI: 10.1039/c8cp06314a] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chemical degradation of TAA occurs through the conical intersection present between ground and first excited singlet state with C–N bond dissociation, which channels the excited molecules to dissociate and form radical fragments or cyclized products.
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Affiliation(s)
- J. Vijaya sundar
- Department of Chemistry
- Indian Institute of Technology Madras
- Chennai 600036
- India
| | - V. Subramanian
- Inorganic and Physical Chemistry Laboratory
- Central Leather Research Institute
- Chennai 600020
- India
| | - B. Rajakumar
- Department of Chemistry
- Indian Institute of Technology Madras
- Chennai 600036
- India
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27
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Margret M, Menaka M, Subramanian V, Baskaran R, Venkatraman B. Non-destructive inspection of hidden corrosion through Compton backscattering technique. Radiat Phys Chem Oxf Engl 1993 2018. [DOI: 10.1016/j.radphyschem.2018.07.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Ghirardi M, Subramanian V, Wecker M, Smolinski S, Antonio R, Xiong W, Gonzalez-Ballester D, Dubini A. Survey of the anaerobic metabolism of various laboratory wild-type Chlamydomonas reinhardtii strains. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.05.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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29
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Margret M, Subramanian V, Baskaran R, Venkatraman B. Detection of scales and its thickness determination in industrial pipes using Compton backscattering system. Rev Sci Instrum 2018; 89:113117. [PMID: 30501299 DOI: 10.1063/1.5039579] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 10/31/2018] [Indexed: 06/09/2023]
Abstract
The ability to detect and quantify scales in pipes has been an important yardstick for efficient transfer of fluids in domestic as well as in application related industries. Knowledge of different kinds of scales formed has become a precondition for trouble-shooting in operational lines. In this paper, collimated Compton backscattered gamma rays from a radioactive source have been used to inspect the scales by automatic scanning in steps along the axial direction of different pipes. The methodology has been extended for the quantification of scales that prevails in the real functionality of extensive usage of fluids. To aid for descaling processes, the desideratum is the density determination of scales and this parameter is quantified non-destructively and is also validated with the standard density. The described non-intrusive gamma ray densitometry is quite promising, efficient and has highly reliable results for scale detection with the squared correlation coefficient of 0.98. The proposed technique shows a better linearity than the gammatography technique.
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Affiliation(s)
- M Margret
- Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India
| | - V Subramanian
- Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India
| | - R Baskaran
- Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India
| | - B Venkatraman
- Health, Safety and Environment Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India
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30
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Singh UK, Ramanathan AL, Subramanian V. Groundwater chemistry and human health risk assessment in the mining region of East Singhbhum, Jharkhand, India. Chemosphere 2018; 204:501-513. [PMID: 29679871 DOI: 10.1016/j.chemosphere.2018.04.060] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Revised: 03/20/2018] [Accepted: 04/11/2018] [Indexed: 05/12/2023]
Abstract
Groundwater chemistry of mining region of East Singhbhum district having complex contaminant sources were investigated based on heavy metals loads and other hydrochemical constituents. This study aimed to identify the degree of heavy metals exposure and their potential health risk to local population. The results of hydrochemical analysis showed that Na+, K+, and Ca2+ ions are the dominant cations in the groundwater, while HCO3-, F- and Cl- ions dominate the anionic part of the groundwater. The weathering process was considered the dominant factor to determine the major ionic composition in the study area. Compositional analysis for heavy metal has identified that groundwater of the study area is contaminated by Cd, Pb and Cr elements. Source of these metals have been identified as an anthropogenic inputs from mining activities and mineral processing units. Health risk analysis of individual heavy metal for chronic daily intake (CDI) and hazard quotient (HQ) was found in the order of Cr > As > Cd > Pb which is indicating high health risk for the population. In addition, Hazard Index (HI) analysis for heavy metals was found significantly high (>1) which is considered as a threat for human population because they have the tendency to accumulate in the body and cause variety of diseases like kidney problem, dysfunction of liver and renal cortex as well as cancer.
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Affiliation(s)
- Umesh Kumar Singh
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
| | - A L Ramanathan
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - V Subramanian
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
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31
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Venugopal S, Kao C, Chandna R, Sulochana KN, Subramanian V, Chen M, Kini RM, Ge R. Angio-3, a 10-residue peptide derived from human plasminogen kringle 3, suppresses tumor growth in mice via impeding both angiogenesis and vascular permeability. Angiogenesis 2018; 21:653-665. [DOI: 10.1007/s10456-018-9616-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 04/18/2018] [Indexed: 12/12/2022]
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32
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Ortiz-Fernandez-Sordo J, Sami SS, Mansilla-Vivar R, Subramanian V, Mannath J, Telakis E, Ragunath K. Corrigendum: Evaluation of a novel infra-red endoscopy system in the assessment of early neoplasia in Barretts esophagus: pilot study from a single center. Dis Esophagus 2018; 31:4975513. [PMID: 29912361 DOI: 10.1093/dote/doy035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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33
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Ortiz-Fernandez-Sordo J, Sami SS, Mansilla-Vivar R, Subramanian V, Mannath J, Telakis E, Ragunath K. Evaluation of a novel infra-red endoscopy system in the assessment of early neoplasia in Barretts esophagus: pilot study from a single center. Dis Esophagus 2018; 31:4714778. [PMID: 29228128 DOI: 10.1093/dote/dox137] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Indexed: 12/11/2022]
Abstract
Infrared endoscopy (IRE) has been shown to be useful in detecting submucosal (SM) invasion in early gastric cancer. Its role in the endoscopic assessment of Barrett's neoplasia has not been reported to date. We aimed in this study to evaluate the role of IRE in the detection and characterization of early neoplastic lesions within Barrett's esophagus (BE). The secondary aim was to explore its usefulness for the assessment of the presence of submucosal invasion in these early neoplastic Barrett's lesions. We included in the study patients with dysplastic BE who were referred to our institution for endoscopic therapy of a previously diagnosed early Barrett's neoplasia. An examination with white light high resolution endoscopy (HRE) and near IRE after intravenous injection of indocyanine green was performed for all patients using an infrared endoscope prototype. Staining on IRE and correlation with final histological staging by endoscopic mucosal resection/surgery or histological diagnosis on mapping biopsies was analyzed. A total of 23 patients were enrolled in our study: 17 of them with 19 visible lesions and 6 patients with flat BE and no lesions. Staining on IRE was noted in 18 cases: 17 (94%) had at least high grade dysplasia (HGD). No stain was noted in 7 cases: final histology was <HGD in 5 (71%) and ≥HGD in 2 (29%). There was statistically significant difference between cases with no stain and any staining on IRE with regard to the presence of ≥HGD [2/7 (29%) vs. 17/18 (94%) P = 0.0022]. Stain was reported as faint in 12 and dense in 6. All 6 cases with dense staining had at least HGD. We concluded that IRE can provide additional information to the currently available white light endoscopy for detecting early neoplastic lesions within BE. IRE also allows detecting HGD and most advanced histology in BE. Usefulness of IRE to detect submucosal involvement in early Barrett's neoplastic lesions needs to be assessed further in larger cohort studies.
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Affiliation(s)
- J Ortiz-Fernandez-Sordo
- National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
| | - S S Sami
- National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
| | - R Mansilla-Vivar
- National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
| | - V Subramanian
- National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
| | - J Mannath
- National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
| | - E Telakis
- National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
| | - K Ragunath
- National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
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34
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Korpal M, Puyang X, Furman C, Zheng GZ, Banka D, Wu J, Zhang Z, Thomas M, Mackenzie C, Yao H, Rimkunas V, Kumar P, Caleb B, Karr C, Subramanian V, Irwin S, Larsen N, Vaillancourt F, Nguyen TV, Davis A, Chan B, Hao MH, O'Shea M, Prajapati S, Agoulnik S, Kuznetsov G, Kumar N, Yu Y, Lai G, Hart A, Eckley S, Fekkes P, Bowser T, Joshi JJ, Selvaraj A, Wardell S, Norris J, Smith S, Reynolds D, Mitchell L, Wang J, Yu L, Kim A, Rioux N, Sahmoud T, Warmuth M, Smith PG, Zhu P. Abstract P1-10-08: Development of a first-in-class oral selective ERα covalent antagonist (SERCA) for the treatment of ERαWT and ERαMUT breast cancer. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-p1-10-08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Mutations in estrogen receptor alpha (ERα) are detected in up to 30% of breast cancer patients who have relapsed during endocrine therapy. ERα mutations functionally confer resistance to existing classes of endocrine therapies, likely through gaining constitutive activity. The fact that current ER-directed therapies are only partially effective in the ERα mutant setting, and that a significant proportion of resistant breast cancer metastases continue to remain dependent on ERα signaling for growth/survival, highlights the critical need to develop the next generation of ERα antagonists that can overcome aberrant ERα activity. Using structure-based drug design approaches we have identified a novel class of ERα antagonist referred to as Selective ERα Covalent Antagonist (SERCA) that inactivate both wild-type and mutant ERα by targeting a unique cysteine residue that is not conserved among other steroid hormone receptors. Biophysical, biochemical and cellular analyses confirm the covalent mechanism of action, specific binding to ER and selective inhibition of ERα-dependent transcription of SERCAs. H3B-6545 is a highly selective SERCA that potently antagonizes wild-type and mutant ERα in biochemical and cell based assays demonstrating increased potency over standard of care and other experimental agents. In vivo, H3B-6545 shows superior efficacy to fulvestrant in the MCF-7 xenograft model with once daily oral dosing, achieving maximal antitumor activity at doses >10x below the maximum tolerated dose in mice. In addition, H3B-6545 shows superior antitumor activity to both tamoxifen and fulvestrant in patient derived xenograft models of breast cancer carrying estrogen receptor mutations. In summary, H3B-6545 is a first-in-class, orally available and selective ER covalent antagonist with a compelling pre-clinical profile that is being developed for the treatment of ERα positive breast cancer.
Citation Format: Korpal M, Puyang X, Furman C, Zheng GZ, Banka D, Wu J, Zhang Z, Thomas M, Mackenzie C, Yao H, Rimkunas V, Kumar P, Caleb B, Karr C, Subramanian V, Irwin S, Larsen N, Vaillancourt F, Nguyen T-V, Davis A, Chan B, Hao MH, O'Shea M, Prajapati S, Agoulnik S, Kuznetsov G, Kumar N, Yu Y, Lai G, Hart A, Eckley S, Fekkes P, Bowser T, Joshi JJ, Selvaraj A, Wardell S, Norris J, Smith S, Reynolds D, Mitchell L, Wang J, Yu L, Kim A, Rioux N, Sahmoud T, Warmuth M, Smith PG, Zhu P. Development of a first-in-class oral selective ERα covalent antagonist (SERCA) for the treatment of ERαWT and ERαMUT breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-10-08.
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Affiliation(s)
- M Korpal
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - X Puyang
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - C Furman
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - GZ Zheng
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - D Banka
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - J Wu
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - Z Zhang
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - M Thomas
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - C Mackenzie
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - H Yao
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - V Rimkunas
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - P Kumar
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - B Caleb
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - C Karr
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - V Subramanian
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - S Irwin
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - N Larsen
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - F Vaillancourt
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - T-V Nguyen
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - A Davis
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - B Chan
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - MH Hao
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - M O'Shea
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - S Prajapati
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - S Agoulnik
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - G Kuznetsov
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - N Kumar
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - Y Yu
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - G Lai
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - A Hart
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - S Eckley
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - P Fekkes
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - T Bowser
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - JJ Joshi
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - A Selvaraj
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - S Wardell
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - J Norris
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - S Smith
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - D Reynolds
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - L Mitchell
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - J Wang
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - L Yu
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - A Kim
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - N Rioux
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - T Sahmoud
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - M Warmuth
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - PG Smith
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
| | - P Zhu
- H3 Biomedicine, Inc., 300 Technology Square, Cambridge, MA; Eisai Inc., 4 Corporate Drive, Andover, MA; Duke University, Research Drive, LSRC Bldg, C251, Durham, NC
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Vijaya Sundar J, Kamaraj M, Subramanian V. Probing the effect of different graphitic nitrogen sites on the aerobic oxidation of thiols to disulfides: a DFT study. Phys Chem Chem Phys 2018; 20:2057-2065. [PMID: 29300059 DOI: 10.1039/c7cp05924h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Functionalized graphene materials are well known for their application in catalyzing the aerobic oxidation of alcohols, hydrocarbons, etc. in an aqueous medium. Despite the fact that a few catalysts are known to oxidize thiols to disulfides, their selectivity is poor and requires oxidants that are not suitable in terms of the principles of green chemistry. Therefore, in this context, an attempt has been made to investigate the possibility of utilizing nitrogen doped graphene for the aerobic oxidation of thiols to disulfides using density functional theory (DFT). Our previous study (V. S. Jeyaraj, M. Kamaraj and V. Subramanian, J. Phys. Chem. C, 2015, 119, 26438-26450) has shed light on the activation of dioxygen to form activated oxygen species (AOS) at different graphitic nitrogen sites. Hence the same has been used to study the two-electron oxidation of thiophenol and methanethiol. The AOS are of three kinds: (1) peroxide type at the edges, (2) superoxide type at the center and (3) ketonic type at edges. The findings from this study indicate that the peroxide type AOS leads to selective formation of diphenyl disulfide, whereas the superoxide type at the center facilitates the formation of hydrogen peroxide which could lead to over-oxidation of disulfide. The oxidation of aromatic thiols (thiophenol) by the ketonic type of AOS is nearly a barrier-less reaction (0.67 kcal mol-1). Similarly, AOS at the edges with the peroxide form can oxidize aliphatic thiols (methanethiol) with a less barrier of 1.55 kcal mol-1, which can be a spontaneous reaction. The mechanism of oxidation is completely different from the oxidative pathway of alcohols by the same AOS. The formation of S-OH species is strictly avoided by the strong stabilization of thiyl radicals over the π-surface of graphene.
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Affiliation(s)
- J Vijaya Sundar
- Chemical Laboratory, CSIR-Central Leather Research Institute, Adyar, Chennai 600 020, India.
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Kajjam AB, Kumar PSV, Subramanian V, Vaidyanathan S. Triphenylamine based yellowish-orange light emitting organic dyes (donor–π–acceptor) for hybrid WLEDs and OLEDs: synthesis, characterization and theoretical study. Phys Chem Chem Phys 2018; 20:4490-4501. [DOI: 10.1039/c7cp08670a] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Six novel yellowish-orange light emitting dye molecules consisting of an electron deficient phenone (acceptor) linked to triphenylamine (donor), were designed and synthesized.
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Affiliation(s)
- Aravind Babu Kajjam
- Department of Chemistry
- National Institute of Technology
- Rourkela 769 008
- India
| | | | - V. Subramanian
- CSIR – Central Leather Research Institute
- Chennai – 600 020
- India
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Sambathkumar B, Varathan E, Subramanian V, Somanathan N. Two-acceptor one-donor random terpolymers comprising thiophene- and phenyl-capped diketopyrrolopyrrole for organic photovoltaics. NEW J CHEM 2018. [DOI: 10.1039/c8nj03536a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of random terpolymers comprising two electron deficient phenyl (PDPP) and thiophene (ThDPP)-capped diketopyrrolopyrrole (DPP) in conjugation with the electron-donating thiophene moiety are synthesised using Stille coupling.
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Affiliation(s)
- B. Sambathkumar
- CSIR-Central Leather Research Institute
- Chennai 600020
- India
- CSIR-Network of Institutes for Solar Energy
- India
| | - E. Varathan
- CSIR-Central Leather Research Institute
- Chennai 600020
- India
- CSIR-Network of Institutes for Solar Energy
- India
| | - V. Subramanian
- CSIR-Central Leather Research Institute
- Chennai 600020
- India
- CSIR-Network of Institutes for Solar Energy
- India
| | - N. Somanathan
- CSIR-Central Leather Research Institute
- Chennai 600020
- India
- CSIR-Network of Institutes for Solar Energy
- India
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Bhat S, Baksi A, Mudedla SK, Natarajan G, Subramanian V, Pradeep T. Au 22Ir 3(PET) 18: An Unusual Alloy Cluster through Intercluster Reaction. J Phys Chem Lett 2017; 8:2787-2793. [PMID: 28586224 DOI: 10.1021/acs.jpclett.7b01052] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
An intercluster reaction between Au25(PET)18 and Ir9(PET)6 producing the alloy cluster, Au22Ir3(PET)18 exclusively, is demonstrated where the ligand PET is 2-phenylethanethiol. Typical reactions of this kind between Au25(PET)18 and Ag25(SR)18, and other clusters reported previously, produce mixed cluster products. The cluster composition was confirmed by detailed high-resolution electrospray ionization mass spectrometry (ESI MS) and other spectroscopic techniques. This is the first example of Ir metal incorporation in a monolayer-protected noble metal cluster. The formation of a single product was confirmed by thin layer chromatography (TLC). Density functional theory (DFT) calculations suggest that the most favorable geometry of the Au22Ir3(PET)18 cluster is one wherein the three Ir atoms are arranged triangularly with one Ir atom at the icosahedral core and the other two on the icosahedral shell. Significant contraction of the metal core was observed due to strong Ir-Ir interactions.
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Affiliation(s)
- Shridevi Bhat
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India
| | - Ananya Baksi
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India
| | - Sathish Kumar Mudedla
- Chemical Laboratory, CSIR-Central Leather Research Institute , Adyar, Chennai 600020, India
| | - Ganapati Natarajan
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India
| | - V Subramanian
- Chemical Laboratory, CSIR-Central Leather Research Institute , Adyar, Chennai 600020, India
| | - Thalappil Pradeep
- DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India
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Varathan E, Subramanian V. The role of sulfur oxidation in controlling the electronic properties of sulfur-containing host molecules for phosphorescent organic light-emitting diodes. Phys Chem Chem Phys 2017; 19:12002-12012. [PMID: 28443899 DOI: 10.1039/c7cp00828g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In this study a series of dibenzothiophene (DBT) derivatives having different valence states of sulfur atoms have been reported as host materials for blue phosphorescent organic light-emitting diodes. Their electronic properties have also been thoroughly investigated to develop structure-property relationships which include the consideration of the effect of various oxidation states of the sulfur atom in the core moiety and linking (C-N linkage) of subunits with the core at different positions. The results obtained from the electronic structure calculations highlight that the triplet energy (ET), singlet-triplet energy difference (ΔEST), reorganization energy for the hole and the injection barrier for the electron decrease with an increase in the oxidation state of the sulfur atom in DBT. On the other hand, the injection barrier for the hole and the reorganization energy for the electron increase upon increasing the oxidation state of the sulfur atom present in the DBT.
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Affiliation(s)
- E Varathan
- Chemical Laboratory, CSIR-Central Leather Research Institute, Adyar, Chennai-600 020, India.
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Subramanian V, Sahoo P, Malathi N, Ananthanarayanan R, Baskaran R, Saha B. Studies on Chemical Speciation of Sodium Aerosols Produced in Sodium Fire. NUCL TECHNOL 2017. [DOI: 10.13182/nt09-a4100] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- V. Subramanian
- Indira Gandhi Centre for Atomic Research Radiological Safety Division, Safety Group, Kalpakkam – 603 102 Tamil Nadu, India
| | - P. Sahoo
- Indira Gandhi Centre for Atomic Research, Innovative Instrumentation Section Electronics and Instrumentation Group, Kalpakkam – 603 102 Tamil Nadu, India
| | - N. Malathi
- Indira Gandhi Centre for Atomic Research, Innovative Instrumentation Section Electronics and Instrumentation Group, Kalpakkam – 603 102 Tamil Nadu, India
| | - R. Ananthanarayanan
- Indira Gandhi Centre for Atomic Research, Innovative Instrumentation Section Electronics and Instrumentation Group, Kalpakkam – 603 102 Tamil Nadu, India
| | - R. Baskaran
- Indira Gandhi Centre for Atomic Research Radiological Safety Division, Safety Group, Kalpakkam – 603 102 Tamil Nadu, India
| | - B. Saha
- Indira Gandhi Centre for Atomic Research, Innovative Instrumentation Section Electronics and Instrumentation Group, Kalpakkam – 603 102 Tamil Nadu, India
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Subramanian V, Baskaran R, Misra J, Indira R. Experimental Study on the Behavior of Suspended Aerosols of Sodium and Nonradioactive Fission Products (SrO2and CeO2) in a Closed Vessel. NUCL TECHNOL 2017. [DOI: 10.13182/nt11-a12544] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- V. Subramanian
- Indira Gandhi Centre for Atomic Research, Radiological Safety Division Kalpakkam-603 102, Tamil Nadu, India
| | - R. Baskaran
- Indira Gandhi Centre for Atomic Research, Radiological Safety Division Kalpakkam-603 102, Tamil Nadu, India
| | - J. Misra
- Indira Gandhi Centre for Atomic Research, Radiological Safety Division Kalpakkam-603 102, Tamil Nadu, India
| | - R. Indira
- Indira Gandhi Centre for Atomic Research, Radiological Safety Division Kalpakkam-603 102, Tamil Nadu, India
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Affiliation(s)
- V. Subramanian
- Indira Gandhi Centre for Atomic Research, Radiological Safety Division Kalpakkam, Tamil Nadu, India
| | - R. Baskaran
- Indira Gandhi Centre for Atomic Research, Radiological Safety Division Kalpakkam, Tamil Nadu, India
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Affiliation(s)
- V. Subramanian
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110 067, India
| | - K. K. Saxena
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110 067, India
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Prakash M, Subramanian V. Ab initio and density functional theory (DFT) studies on triflic acid with water and protonated water clusters. J Mol Model 2016; 22:293. [PMID: 27888404 DOI: 10.1007/s00894-016-3158-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 11/08/2016] [Indexed: 02/04/2023]
Abstract
The structure, stability and infrared spectral signatures of triflic acid (TA) with water clusters (Wn) and protonated water clusters (TAH+Wn, n = 1 - 6) were computed using DFT and MP2 methods. Our calculations show that a minimum of three water molecules are necessary to stabilize the dissociated zwitterionic form of TA. It can be seen from the results that there is no significant movement of protons in smaller (n = 1 and 2) and linear (n = 1 - 6) types of water clusters. Further, the geometries of TAWn clusters first form a neutral pair (NP) to contact ion pair (CIP), then form a solvent separated ion pair (SSIP) in a water hexamer. These findings reveal that proton transfer may take place through NP to CIP and then CIP to SSIP. The calculated binding energies (BEs) of ion pair clusters is always higher than that of NP clusters (i.e., more stable than the NP). Existing excess proton linear chain clusters transfer a proton to adjacent water molecules via a Grotthuss mechanism, whereas the same isomers in the branched motifs do not conduct protons. Examination of geometrical parameters and infrared frequencies reveals hydronium ion (H3O+ also called Eigen cation) formation in both TAWn and protonated TAWn clusters. The stability of Eigen water clusters is three times higher than that of other non-Eigen water clusters. Our study shows clearly that formation of ion pairs in TAWn and TAH+Wn clusters greatly favors proton transfer to neighboring water molecules and also enhances the stability of these complexes.
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Affiliation(s)
- M Prakash
- Department of Chemistry and Research Institute, SRM University, Kattankulathur, 603203, Tamil Nadu, India
- Chemical Laboratory, CSIR-Central Leather Research Institute, Adyar, Chennai, 600 020, India
| | - V Subramanian
- Chemical Laboratory, CSIR-Central Leather Research Institute, Adyar, Chennai, 600 020, India.
- Academy of Scientific and Innovative Research (AcSIR), CSIR-CLRI Campus, Chennai, 600 020, India.
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Chhaya V, Saxena S, Cecil E, Subramanian V, Curcin V, Majeed A, Pollok RC. Steroid dependency and trends in prescribing for inflammatory bowel disease - a 20-year national population-based study. Aliment Pharmacol Ther 2016; 44:482-94. [PMID: 27375210 DOI: 10.1111/apt.13700] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 04/12/2016] [Accepted: 05/26/2016] [Indexed: 12/21/2022]
Abstract
BACKGROUND It is unclear whether adherence to prescribing standards has been achieved in inflammatory bowel disease (IBD). AIM To determine how prescribing of 5-aminosalicylates (5-ASAs), steroids and thiopurines has changed in response to emerging evidence. METHODS We examined trends in oral and topical therapies in 23 509 incident IBD cases (6997 with Crohn's disease and 16 512 with ulcerative colitis) using a nationally representative sample between 1990 and 2010. We created five eras according to the year of diagnosis: era 1 (1990-1993), era 2 (1994-1997), era 3 (1998-2001), era 4 (2002-2005) and era 5 (2006-2010). We calculated the proportion of patients treated with prolonged 5-ASAs (>12 months) and steroid dependency, defined as prolonged steroids (>3 months) or recurrent (restarting within 3 months) steroid exposure. We calculated the cumulative probability of receiving each medication using survival analysis. RESULTS Half of the Crohn's disease patients were prescribed prolonged oral 5-ASAs during the study, although this decreased between era 3 and 5 from 61.8% to 56.4% (P = 0.002). Thiopurine use increased from 14.0% to 47.1% (P < 0.001) between era 1 and 5. This coincided with a decrease in steroid dependency from 36.5% to 26.8% (P < 0.001) between era 1 and 2 and era 4 and 5 respectively. In ulcerative colitis, 49% of patients were maintained on prolonged oral 5-ASAs. Despite increasing thiopurine use, repeated steroid exposure increased from 15.3% to 17.8% (P = 0.02) between era 1 and 2 and era 4 and 5 respectively. CONCLUSIONS Prescribing in clinical practice insufficiently mirrors the evidence base. Physicians should direct management towards reducing steroid dependency and optimising 5-ASA use in patients with IBD.
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Affiliation(s)
- V Chhaya
- Department of Gastroenterology, St George's University Hospital, London, UK
| | - S Saxena
- Department of Primary Care and Public Health, Imperial College, London, UK
| | - E Cecil
- Department of Primary Care and Public Health, Imperial College, London, UK
| | - V Subramanian
- Department of Gastroenterology, St James University Hospital, Leeds, UK
| | - V Curcin
- Department of Health and Social Care Research, King's College London, London, UK
| | - A Majeed
- Department of Primary Care and Public Health, Imperial College, London, UK
| | - R C Pollok
- Department of Gastroenterology, St George's University Hospital, London, UK
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Cai M, Palčić A, Subramanian V, Moldovan S, Ersen O, Valtchev V, Ordomsky V, Khodakov A. Direct dimethyl ether synthesis from syngas on copper–zeolite hybrid catalysts with a wide range of zeolite particle sizes. J Catal 2016. [DOI: 10.1016/j.jcat.2016.02.025] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Azhagiya Singam ER, Rajapandian V, Subramanian V. Molecular dynamics simulation study on the interaction of collagen-like peptides with gelatinase-A (MMP-2). Biopolymers 2016; 101:779-94. [PMID: 24374600 DOI: 10.1002/bip.22457] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 12/21/2013] [Accepted: 12/21/2013] [Indexed: 12/19/2022]
Abstract
Although several models have been proposed for the interaction of collagen with gelatinase-A (matrix metalloproteinases-2 (MMP-2)), the extensive role of each domain of gelatinase A in hydrolyzing the collagens with and without interruptions is still elusive. Molecular docking, molecular dynamics (MD) simulation, normal mode analysis (NMA) and framework rigidity optimized dynamics algorithm (FRODAN) based analysis were carried out to understand the function of various domains of MMP-2 upon interaction with collagen like peptides. The results reveal that the collagen binding domain (CBD) binds to the C-terminal of collagen like peptide with interruption. CBD helps in unwinding the loosely packed interrupted region of triple helical structure to a greater extent. It can be possible to speculate that the role of hemopexin (HPX) domain is to prevent further unwinding of collagen like peptide by binding to the other end of the collagen like peptide. The catalytic (CAT) domain then reorients itself to interact with the part of the unwound region of collagen like peptide for further hydrolysis. In conclusion the CBD of MMP-2 recognizes the collagen and aids in unwinding the collagen like peptide with interruptions, and the HPX domain of MMP-2 binds to the other end of the collagen allowing CAT domain to access the cleavage site. This study provides a comprehensive understanding of the structural basis of collagenolysis by MMP-2.
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Affiliation(s)
- E R Azhagiya Singam
- Chemical Laboratory, Council of Scientific and Industrial Research, Central Leather Research Institute, Adyar, Chennai, 600 020, Tamil Nadu, India
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Thirumalai Swamy S, Anu Radha C, Arun G, Kathirvel M, Subramanian V. Performance evaluation of gated volumetric modulated arc therapy. INT J RADIAT RES 2016. [DOI: 10.18869/acadpub.ijrr.14.2.81] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Bejoymohandas KS, Kumar A, Sreenadh S, Varathan E, Varughese S, Subramanian V, Reddy MLP. A Highly Selective Chemosensor for Cyanide Derived from a Formyl-Functionalized Phosphorescent Iridium(III) Complex. Inorg Chem 2016; 55:3448-61. [PMID: 27008242 DOI: 10.1021/acs.inorgchem.5b02885] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A new phosphorescent iridium(III) complex, bis[2',6'-difluorophenyl-4-formylpyridinato-N,C4']iridium(III) (picolinate) (IrC), was synthesized, fully characterized by various spectroscopic techniques, and utilized for the detection of CN(-) on the basis of the widely known hypothesis of the formation of cyanohydrins. The solid-state structure of the developed IrC was authenticated by single-crystal X-ray diffraction. Notably, the iridium(III) complex exhibits intense red phosphorescence in the solid state at 298 K (ΦPL = 0.16) and faint emission in acetonitrile solution (ΦPL = 0.02). The cyanide anion binding properties with IrC in pure and aqueous acetonitrile solutions were systematically investigated using two different channels: i.e., by means of UV-vis absorption and photoluminescence. The addition of 2.0 equiv of cyanide to a solution of the iridium(III) complex in acetonitrile (c = 20 μM) visibly changes the color from orange to yellow. On the other hand, the PL intensity of IrC at 480 nm was dramatically enhanced ∼5.36 × 10(2)-fold within 100 s along with a strong signature of a blue shift of the emission by ∼155 nm with a detection limit of 2.16 × 10(-8) M. The cyanohydrin formation mechanism is further supported by results of a (1)H NMR titration of IrC with CN(-). As an integral part of this work, phosphorescent test strips have been constructed by impregnating Whatman filter paper with IrC for the trace detection of CN(-) in the contact mode, exhibiting a detection limit at the nanogram level (∼265 ng/mL). Finally, density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations were performed to understand the electronic structure and the corresponding transitions involved in the designed phosphorescent iridium(III) complex probe and its cyanide adduct.
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Affiliation(s)
- K S Bejoymohandas
- Materials Science and Technology Division, CSIR-Network of Institutes for Solar Energy, CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST) , Thiruvananthapuram 695 019, India.,Academy of Scientific and Innovative Research (AcSIR) , New Delhi 110025, India
| | - Ajay Kumar
- Materials Science and Technology Division, CSIR-Network of Institutes for Solar Energy, CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST) , Thiruvananthapuram 695 019, India
| | - S Sreenadh
- Materials Science and Technology Division, CSIR-Network of Institutes for Solar Energy, CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST) , Thiruvananthapuram 695 019, India
| | - E Varathan
- Chemical Laboratory, CSIR-Central Leather Research Institute , Chennai 600 020, India
| | - S Varughese
- Materials Science and Technology Division, CSIR-Network of Institutes for Solar Energy, CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST) , Thiruvananthapuram 695 019, India
| | - V Subramanian
- Chemical Laboratory, CSIR-Central Leather Research Institute , Chennai 600 020, India
| | - M L P Reddy
- Materials Science and Technology Division, CSIR-Network of Institutes for Solar Energy, CSIR-National Institute for Interdisciplinary Science & Technology (CSIR-NIIST) , Thiruvananthapuram 695 019, India.,Academy of Scientific and Innovative Research (AcSIR) , New Delhi 110025, India
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Sankar U, Surya Kumar CV, Subramanian V, Balasubramanian KK, Mahalakshimi S. Stereo-, Regio-, and Chemoselective [3 + 2]-Cycloaddition of (2E,4E)-Ethyl 5-(Phenylsulfonyl)penta-2,4-dienoate with Various Azomethine Ylides, Nitrones, and Nitrile Oxides: Synthesis of Pyrrolidine, Isoxazolidine, and Isoxazoline Derivatives and a Computational Study. J Org Chem 2016; 81:2340-54. [PMID: 26886393 DOI: 10.1021/acs.joc.5b02845] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
One-pot chemo-, regio-, and stereoselective synthesis of series of heterocyclic and spiroheterocyclic compounds was accomplished through mono- and bis[3 + 2]-cycloaddition reactions of (2E,4E)-ethyl 5-(phenylsulfonyl)penta-2,4-dienoate as a dipolarophile with azomethine ylides, nitrones, and nitrile oxides in good yields. The structures of the products were established by spectroscopic techniques as well as by single-crystal XRD study, and DFT calculations were performed to further understand the mechanism of this [3 + 2]-cycloaddition reaction.
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Affiliation(s)
- Ulaganathan Sankar
- Department of Chemistry, Pachaiyappa's College, University of Madras , Chennai 600030, India
| | - Ch Venkata Surya Kumar
- Chemical Laboratory, CSIR-Central Leather Research Institute , Adyar, Chennai 600020, India
| | - V Subramanian
- Chemical Laboratory, CSIR-Central Leather Research Institute , Adyar, Chennai 600020, India
| | - K K Balasubramanian
- INSA Senior Scientist, Department of Chemistry, Indian Institute of Technology Madras , Chennai 600020, India
| | - S Mahalakshimi
- Department of Chemistry, Pachaiyappa's College, University of Madras , Chennai 600030, India
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