12 results on '"Akanksha Bapna"'
Search Results
2. Handbook on Measuring 21st Century Skills
- Author
-
Akanksha Bapna, Namrata Sharma, Kaushik, Ambika, and Kumar, Arushi
- Published
- 2017
- Full Text
- View/download PDF
3. Social attitudes towards the English language in Bihar
- Author
-
Hayes, David, Akanksha Bapna, Sunaina Khun, and Keedwell, Andy
- Published
- 2016
- Full Text
- View/download PDF
4. New light on multidrug binding by an ATP-binding-cassette transporter
- Author
-
Saroj Velamakanni, Hendrik W. van Veen, Henrietta Venter, Barbara Woebking, Akanksha Bapna, Richard A. Shilling, and Sanjay Shahi
- Subjects
Models, Molecular ,Molecular Sequence Data ,Antineoplastic Agents ,ATP-binding cassette transporter ,Biology ,Toxicology ,Protein structure ,Animals ,Humans ,ATP Binding Cassette Transporter, Subfamily B, Member 1 ,Amino Acid Sequence ,Homology modeling ,Peptide sequence ,ATP-binding domain of ABC transporters ,Pharmacology ,Genetics ,chemistry.chemical_classification ,Binding Sites ,Biological Transport ,Transporter ,Drug Resistance, Multiple ,Protein Structure, Tertiary ,Amino acid ,Multiple drug resistance ,Biochemistry ,chemistry ,Drug Resistance, Neoplasm ,Mutation ,ATP-Binding Cassette Transporters - Abstract
ATP-binding-cassette (ABC) multidrug transporters confer multidrug resistance to pathogenic microorganisms and human tumour cells by mediating the extrusion of structurally unrelated chemotherapeutic drugs from the cell. The molecular basis by which ABC multidrug transporters bind and transport drugs is far from clear. Genetic analyses during the past 14 years reveal that the replacement of many individual amino acids in mammalian multidrug resistance P-glycoproteins can affect cellular resistance to drugs, but these studies have failed to identify specific regions in the primary amino acid sequence that are part of a defined drug-binding pocket. The recent publication of an X-ray crystallographic structure of the bacterial P-glycoprotein homologue MsbA and an MsbA-based homology model of human P-glycoprotein creates an opportunity to compare the original mutagenesis data with the three-dimensional structures of transporters. Our comparisons reveal that mutations that alter specificity are present in three-dimensional 'hotspot' regions in the membrane domains of P-glycoprotein.
- Published
- 2006
5. Angiopoietin-1 promotes functional neovascularization that relieves ischemia by improving regional reperfusion in a swine chronic myocardial ischemia model
- Author
-
Wei Li, Eugene K.W. Sim, Winston Shim, Hwee Choo Ong, Li Zhang, Yean-Teng Lim, In-Chin Song, Shiqi Li, Seng Chye Chuah, Philip Wong, Ruowen Ge, and Akanksha Bapna
- Subjects
Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,Swine ,Endocrinology, Diabetes and Metabolism ,Genetic Vectors ,Clinical Biochemistry ,Myocardial Ischemia ,Ischemia ,Neovascularization, Physiologic ,Myocardial Reperfusion ,Coronary Angiography ,Adenoviridae ,Neovascularization ,Angiopoietin ,Coronary circulation ,Coronary Circulation ,Internal medicine ,Angiopoietin-1 ,medicine ,Animals ,Humans ,Pharmacology (medical) ,Molecular Biology ,DNA Primers ,Analysis of Variance ,Reverse Transcriptase Polymerase Chain Reaction ,business.industry ,Biochemistry (medical) ,Genetic Therapy ,Cell Biology ,General Medicine ,medicine.disease ,Coronary Vessels ,Immunohistochemistry ,medicine.anatomical_structure ,Regional Blood Flow ,Ventricle ,Cardiology ,Arteriogenesis ,medicine.symptom ,business ,Perfusion ,Artery - Abstract
This study investigates the long-term angiogenic effects of ANG-1 and VEGF in a swine chronic myocardial ischemia model. Four-weeks after gradual occlusion of the left circumflex coronary artery by ameroid constrictor, animals were injected with recombinant adenoviral vectors carrying either human ANG-1 (n=9), human VEGF(165) (n=10) or empty vector (n=7) into the left ventricle free wall supplied by the constricted artery. Left ventricular perfusion in animals that received AdANG-1 (3.25+/-0.16 ml/min/g, p
- Published
- 2006
6. Similarities between ATP-dependent and ion-coupled multidrug transporters
- Author
-
Saroj Velamakanni, Henrietta Venter, Lekshmy Balakrishnan, Barbara Woebking, Sanjay Shahi, Akanksha Bapna, and H.W. van Veen
- Subjects
biology ,Chemistry ,Lactococcus lactis ,Membrane Transport Proteins ,Membrane Transporters ,Biological membrane ,biology.organism_classification ,Biochemistry ,Antiporters ,Drug Resistance, Multiple ,Adenosine Triphosphate ,Membrane ,Multidrug Resistance-Associated Proteins ,Multidrug transporter ,ATP-binding domain of ABC transporters - Abstract
The movement of drugs across biological membranes is mediated by two major classes of membrane transporters. Primary-active, ABC (ATP-binding cassette) multidrug transporters are dependent on ATP-binding/hydrolysis, whereas secondary-active multidrug transporters are coupled to the proton (or sodium)-motive force that exists across the plasma membrane. Recent work on LmrA, an ABC multidrug transporter in Lactococcus lactis, suggests that primary- and secondary-active multidrug transporters share functional and structural features. Some of these similarities and their implications for the mechanism of transport by ABC multidrug transporters will be discussed.
- Published
- 2005
7. Angiopoietin 1 Promotes Tumor Angiogenesis and Tumor Vessel Plasticity of Human Cervical Cancer in Mice
- Author
-
Injune Kim, Ming Teh, Akanksha Bapna, Peter Mack, Gou Young Koh, Ruowen Ge, and Winston Shim
- Subjects
Vascular Endothelial Growth Factor A ,Uterine Cervical Neoplasms ,Endothelial Growth Factors ,Adenocarcinoma ,Receptor tyrosine kinase ,Adenoviridae ,Metastasis ,HeLa ,Neovascularization ,Mice ,Angiopoietin-1 ,medicine ,Animals ,Humans ,Lymphokines ,Membrane Glycoproteins ,Neovascularization, Pathologic ,biology ,Vascular Endothelial Growth Factors ,Gene Transfer Techniques ,Cell Biology ,biology.organism_classification ,medicine.disease ,Vascular endothelial growth factor A ,medicine.anatomical_structure ,Apoptosis ,Immunology ,cardiovascular system ,Cancer research ,biology.protein ,Blood Vessels ,Female ,medicine.symptom ,HeLa Cells ,Blood vessel - Abstract
Angiopoietins have been increasingly implicated to play important roles in blood vessel formation, remodeling, maturation, and maintenance. However, their roles in tumor angiogenesis and hence tumor growth and metastasis still remain uncertain. In this work, angiopoietin 1 expression was amplified in human cervical cancer HeLa cells by stable transfection or recombinant human adenovirus-mediated gene transfer. We show that increased angiopoietin 1 expression promoted in vivo growth of human cervical cancers in mice by promoting tumor angiogenesis and inhibiting tumor cell apoptosis. Furthermore, we also show for the first time that overexpression of angiopoietin 1 also leads to increased tumor vessel plasticity with a large number of vessels lacking periendothelial supporting cells. These results indicate that angiopoietin 1 promotes tumor angiogenesis and tumor vessel plasticity of human cervical cancer in mice.
- Published
- 2002
8. Two proton translocation pathways in a secondary active multidrug transporter
- Author
-
Akanksha Bapna, Tai-Ping Fan, Saroj Velamakanni, Henrietta Venter, Luca Federici, Ben F. Luisi, Hendrik W. van Veen, BAPNA, A, FEDERICI, L, Venter, Henrietta, Velamakanni, S, Luisi, Ben F, FAN, T, and Van Veen, HW
- Subjects
Models, Molecular ,Physiology ,Biology ,Applied Microbiology and Biotechnology ,Biochemistry ,Microbiology ,Antiporters ,Bacterial Proteins ,Ethidium ,Escherichia coli ,Electrochemical gradient ,Proton translocation ,Lactococcus lactis ,Membrane Transport Proteins ,Biological Transport ,Cell Biology ,biology.organism_classification ,Major facilitator superfamily ,Protein Structure, Tertiary ,Multiple drug resistance ,secondary active drug transport ,proton coupling ,carboxylate ,lactococcus lactis ,multidrug resistance ,Amino Acid Substitution ,Mutagenesis, Site-Directed ,Protons ,Multidrug transporter ,Biotechnology - Abstract
LmrP is a secondary active multidrug transporter from Lactococcus lactis. The protein belongs to the major facilitator superfamily and utilizes the electrochemical proton gradient (inside negative and alkaline) to extrude a wide range of lipophilic cations from the cell. Previous work has indicated that ethidium, a monovalent cationic substrate, is exported by LmrP by electrogenic antiport with two (or more) protons. This observation raised the question whether these protons are translocated sequentially along the same pathway, or through different routes. To address this question, we constructed a 3-D homology model of LmrP based on the high-resolution structure of the glycerol-3P/Pi antiporter GlpT from Escherichia coli, and we tested by mutagenesis the possible proton conduction points suggested by this model. Similar to the template, LmrP is predicted to contain an internal cavity formed at the interface between the two halves of the transporter. On the surface of this cavity lie two clusters of polar, aromatic and carboxylate residues with potentially important function in proton shuttling. Cluster 1 in the C-terminal half contains D235 and E327 in immediate proximity of each other, and is located near the apex of the cavity. Cluster 2 in the N-terminal half contains D142. Analyses of LmrP mutants containing charge-conservative or carboxyl-to-amide replacements at positions 142, 235 and 327 suggest that D142 is part of a dedicated proton translocation pathway in the ethidium translocation reaction. In contrast, D235 and E327 are part of an independent pathway, in which D235 interacts with protons. E327 appears to modulate the pKa of D235 and plays a role in the interaction with ethidium. These results are consistent with the proposal that major facilitator superfamily proteins consist of two membrane domains, one of which is involved in substrate binding and the other in ion coupling, and they indicate that there are two proton conduction pathways at play in the transport mechanism.
- Published
- 2007
9. Polymer-assisted, multi-step solution phase synthesis and biological screening of histone deacetylase inhibitors
- Author
-
Tai-Ping Fan, Mark Ladlow, Emma Vickerstaffe, Steven V. Ley, Brian H. Warrington, and Akanksha Bapna
- Subjects
Histone deacetylase 5 ,Molecular Structure ,Neovascularization, Pathologic ,HDAC11 ,Chemistry ,Angiogenesis ,Histone deacetylase 2 ,Polymers ,HDAC10 ,Organic Chemistry ,Biochemistry ,Coculture Techniques ,Cell biology ,Endothelial stem cell ,Histone Deacetylase Inhibitors ,Humans ,Histone deacetylase ,Physical and Theoretical Chemistry ,Solution phase synthesis ,Cells, Cultured ,Cell Proliferation - Abstract
The polymer-assisted solution phase synthesis (PASP) of an array of histone deacetylase (HDAc) inhibitors is described. HDAc inhibitors have considerable potential as new anti-proliferative agents. Selected compounds were shown to inhibit both human endothelial cell proliferation, and the formation of tubules (neovascularisation) in an in vitro model of angiogenesis.
- Published
- 2004
10. Contents Vol. 12, 2007
- Author
-
Henrietta Venter, Erwin Z. Mangubat, Cornelia Grosse, Christopher Mulligan, Tamisha McGeary, Janos K. Lanyi, Ronald A. Skurray, Tsai-Tien Tseng, Melissa H. Brown, David J. Kelly, Mohammad M. Aboulwafa, Robert J. Zahm, Carol-Ann Bourne, Akanksha Bapna, Gavin H. Thomas, Dietrich H. Nies, Margarida Palma, Tai-Ping Fan, Saroj Velamakanni, Ian T. Paulsen, Victoria T. Johnson, Milton H. Saier, Luca Federici, Isabel Spencer-Martins, Karl A. Hassan, Eric Jakobsson, André Goffeau, Philippe Baret, Hendrik W. van Veen, Mary E. Pacold, S. L. Sutrina, Qinghu Ren, Ben F. Luisi, Allison M. McMahon, and Susann Friedrich
- Subjects
Engineering ,Chemical engineering ,business.industry ,Environmental chemistry ,business ,Molecular Biology ,Applied Microbiology and Biotechnology ,Microbiology ,Biotechnology - Published
- 2007
11. Subject Index Vol. 12, 2007
- Author
-
Gavin H. Thomas, Mohammad M. Aboulwafa, Melissa H. Brown, David J. Kelly, Allison M. McMahon, Tai-Ping Fan, Robert J. Zahm, Henrietta Venter, Isabel Spencer-Martins, Victoria T. Johnson, Saroj Velamakanni, Erwin Z. Mangubat, Christopher Mulligan, Tamisha McGeary, Janos K. Lanyi, Akanksha Bapna, Luca Federici, Cornelia Grosse, Ben F. Luisi, Dietrich H. Nies, Carol-Ann Bourne, Susann Friedrich, Milton H. Saier, Mary E. Pacold, Philippe Baret, Hendrik W. van Veen, Margarida Palma, Tsai-Tien Tseng, Ian T. Paulsen, S. L. Sutrina, Qinghu Ren, Karl A. Hassan, Eric Jakobsson, André Goffeau, and Ronald A. Skurray
- Subjects
Index (economics) ,Statistics ,Physiology ,Subject (documents) ,Molecular Biology ,Applied Microbiology and Biotechnology ,Microbiology ,Biotechnology ,Mathematics - Published
- 2007
12. Adenovirus‐Mediated Gene Transfer of Angiopoietin‐1 Induces Angiogenesis in the Chronic Ischemic Myocardium
- Author
-
Li Zhang, Winston Shim, Tai Tian Lim, Eugene Sim, Akanksha Bapna, Oakley Reida Menshawe El, Yean-Teng Lim, Ming Teh, and Ruowen Ge
- Subjects
Pulmonary and Respiratory Medicine ,Oncology ,medicine.medical_specialty ,business.industry ,Angiogenesis ,Ischemic myocardium ,Gene transfer ,University hospital ,Angiopoietin-1 ,Internal medicine ,Medicine ,Surgery ,Cardiology and Cardiovascular Medicine ,business - Abstract
Adenovirus-Mediated Gene Transfer of Angiopoietin-1 Induces Angiogenesis in the Chronic Ischemic Myocardium Li Zhang1, Akanksha Bapna2, Winston Shim, Oakley Reida El1, Yean Teng Lim3, Tai Tian Lim4, Ming Teh5, Ruowen Ge2, Eugene Sim1. 1Department of Surgery, Faculty of Medicine, National University of Singapore, 2Department of Biological Science, Faculty of Science, National University of Singapore, 3Cardiac Department, National University Hospital, 4Department of Cardiology, National Heart Center, 5Department of Pathology, National University Hospital, Singapore.
- Published
- 2002
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.