91 results on '"Hannan, F"'
Search Results
2. Cognitive decline in thrombotic thrombocytopenic purpura survivors: The role of white matter health as assessed by MRI.
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Hannan, F., Hamilton, J., Patriquin, C. J., Pavenski, K., Jurkiewicz, M. T., Tristao, L., Owen, A. M., Kosalka, P. K., Deoni, S. C. L., Théberge, J., Mandzia, J., Huang, S. H. S., and Thiessen, J. D.
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THROMBOTIC thrombocytopenic purpura , *WHITE matter (Nerve tissue) , *BLOOD platelet aggregation , *COGNITION disorders , *CINGULATE cortex , *MAGNETIC resonance imaging , *FRONTAL lobe , *PARIETAL lobe - Abstract
Summary: Immune‐mediated thrombotic thrombocytopenic purpura (iTTP) is a rare condition caused by severe ADAMTS13 deficiency, leading to platelet aggregation and thrombosis. Despite treatment, patients are prone to cognitive impairment and depression. We investigated brain changes in iTTP patients during remission using advanced magnetic resonance imaging (MRI) techniques, correlating these changes with mood and neurocognitive tests. Twenty iTTP patients in remission (30 days post‐haematological remission) were compared with six healthy controls. MRI scans, including standard and specialized sequences, were conducted to assess white matter health. Increased T1 relaxation times were found in the cingulate cortex (p < 0.05), and elevated T2 relaxation times were observed in the cingulate cortex, frontal, parietal and temporal lobes (p < 0.05). Pathological changes in these areas are correlated with impaired cognitive and depressive scores in concentration, short‐term memory and verbal memory. This study highlights persistent white matter damage in iTTP patients, potentially contributing to depression and cognitive impairment. Key regions affected include the frontal lobe and cingulate cortex. These findings have significant implications for the acute and long‐term management of iTTP, suggesting a need for re‐evaluation of treatment approaches during both active phases and remission. Further research is warranted to enhance our understanding of these complexities. [ABSTRACT FROM AUTHOR]
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- 2024
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3. 808 Seizures in Sturge-Weber syndrome are associated with disrupted calcium metabolism
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Zecchin, D., primary, Knoepfel, N., additional, Gluck, A.K., additional, Stevenson, M., additional, Richardson, H., additional, Polubothu, S., additional, Inoue, A., additional, Lines, K., additional, Chesover, A., additional, Jacques, T., additional, Hannan, F., additional, Loebel, U., additional, Semple, R., additional, Thakker, R.V., additional, and Kinsler, V.A., additional
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- 2023
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4. Central adiposity raises serum calcium concentrations and increases risk of kidney stone disease
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Lovegrove, C, Besevic, J, Wiberg, A, Lacey, B, Littlejohns, T, Allen, N, Goldsworthy, M, Kim, J, Hannan, F, Curhan, G, Turney, B, McCarthy, M, Mahajan, A, Thakker, R, Holmes, M, Furniss, D, and Howles, S
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- 2022
5. O108 Central adiposity influences serum calcium concentrations and increases risk of kidney stone disease
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Lovegrove, CE, primary, Wiberg, A, additional, Allen, N, additional, Littlejohns, T, additional, Mahajan, A, additional, McCarthy, M, additional, Hannan, F, additional, Thakker, R, additional, Holmes, M, additional, Furniss, D, additional, and Howles, S, additional
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- 2022
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6. Supplement to: Cinacalcet for symptomatic hypercalcemia caused by AP2S1 mutations.
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Howles, S A, Hannan, F M, and Thakker, R V
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- 2016
7. Green Synthesis of Iron Oxide Nanoparticles Using Hibiscus rosa sinensis Flowers and Their Antibacterial Activity
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Buarki, F., primary, AbuHassan, H., additional, Al Hannan, F., additional, and Henari, F. Z., additional
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- 2022
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8. Supplement to: Mutations affecting G-protein subunit α11 in hypercalcemia and hypocalcemia.
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Nesbit, M A, Hannan, F M, and Howles, S A
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- 2013
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9. Switching of Appropriate Transmission Modes in LTE
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Farid, Hasib M. A. B., primary, Sadik, Adil M. J., additional, Razu, Ibrahim K., additional, Hannan, F., additional, and Mahmood, R., additional
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- 2011
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10. Molecular and Cellular Mechanisms of Learning Disabilities: A Focus on Neurofibromatosis Type I
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Shilyansky, Carrie, primary, Li, Weidong, additional, Acosta, M., additional, Elgersma, Y., additional, Hannan, F., additional, Hardt, M., additional, Hunter-Schaedle, K., additional, Krab, L.C., additional, Legius, E., additional, Wiltgen, B., additional, and Silva, Alcino J, additional
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- 2008
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11. List of Contributors
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Acosta, M., primary, Bendotti, Caterina, additional, Blaugrund, Eran, additional, Brunner, Daniela, additional, Borsini, Franco, additional, Cheroni, Cristina, additional, Chesselet, Marie-Françoise, additional, Deadwyler, Sam A., additional, Elgersma, Y., additional, Fahn, Stanley, additional, Gordon, Paul H., additional, Goren, Sari, additional, Goumeniouk, Alexander D., additional, Hallak, Hussein, additional, Hampson, Robert E., additional, Hannan, F., additional, Hardt, M., additional, Hu, Shu-Ching, additional, Hunter, A. Jackie, additional, Hunter-Schaedle, K., additional, Klitgaard, Henrik, additional, Krab, L.C., additional, Leavitt, Blair R., additional, Legius, E., additional, Li, Weidong, additional, Lindner, Mark D., additional, Matagne, Alain, additional, McArthur, Robert A., additional, Menalled, Liliana, additional, Merchant, Kalpana M., additional, Montes, Jacqueline, additional, Schachter, Steven C., additional, Schneider, Lon S., additional, Shilyansky, Carrie, additional, Silva, Alcino J., additional, Speiser, Zipora, additional, Tariot, Pierre N., additional, Tortarolo, Massimo, additional, Wagner, Laura A., additional, White, H. Steve, additional, Wiltgen, B., additional, and Willner, Paul, additional
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- 2008
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12. Calcium Channel as a New Potential Target for Insecticides
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Hall, L. M., primary, Ren, D., additional, Feng, G., additional, Eberl, D. F., additional, Dubald, M., additional, Yang, M., additional, Hannan, F., additional, Kousky, C. T., additional, and Zheng, W., additional
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- 1995
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13. BALANCE AND STRENGTH CHANGES IN ELDERLY SUBJECTS AFTER HEAVY-RESISTANCE STRENGTH TRAINING: 124
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Parsons, Dorubeth, Foster, V., Hannan, F., Dickinson, A., Oliva, P., and Westerlind, K.
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- 1992
14. Mutant mice with calcium-sensing receptor (CaSR) activation have hyperglycemia, that is rectified by calcilytic therapy
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Babinsky, V, Hannan, F, Ramracheya, R, Zhang, F, Nesbit, M, Hugill, A, Bentley, L, Hough, T, Joynson, E, Stewart, M, Aggarwal, A, Prinz-Wohlgenannt, M, Gorvin, C, Kallay, E, Wells, S, Cox, R, Richards, D, Rorsman, P, and Thakker, R
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endocrine system - Abstract
The calcium-sensing receptor (CaSR) is a family C G-protein-coupled receptor (GPCR) that plays a pivotal role in extracellular calcium homeostasis. The CaSR is also highly expressed in pancreatic islet α- and β-cells that secrete glucagon and insulin, respectively. To determine whether the CaSR may influence systemic glucose homeostasis, we characterized a mouse model with a germline gain-of-function CaSR mutation, Leu723Gln, referred to as Nuclear flecks (Nuf). Heterozygous- (CasrNuf/+) and homozygous-affected (CasrNuf/Nuf) mice were shown to have hypocalcemia in association with impaired glucose tolerance and insulin secretion. Oral administration of a CaSR antagonist compound, known as a calcilytic, rectified the glucose intolerance and hypoinsulinemia of CasrNuf/+ mice, and ameliorated glucose intolerance in CasrNuf/Nuf mice. Ex vivo studies showed CasrNuf/+ and CasrNuf/Nuf mice to have reduced pancreatic islet mass and β-cell proliferation. Electrophysiological analysis of isolated CasrNuf/Nuf islets showed CaSR activation to increase the basal electrical activity of β-cells independently of effects on the activity of the ATP-sensitive K+ (KATP) channel. CasrNuf/Nuf mice also had impaired glucose-mediated suppression of glucagon secretion, which was associated with increased numbers of α-cells and a higher α-cell proliferation rate. Moreover, CasrNuf/Nuf islet electrophysiology demonstrated an impairment of α-cell membrane depolarization in association with attenuated α-cell basal KATP channel activity. These studies indicate that the CaSR activation impairs glucose tolerance by a combination of α- and β-cell defects and also influences pancreatic islet mass. Moreover, our findings highlight a potential application of targeted CaSR compounds for modulating glucose metabolism.
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- 2017
15. Identification of a G-Protein Subunit-α11 Gain-of-Function Mutation, Val340Met, in a Family with Autosomal Dominant Hypocalcemia Type 2 (ADH2)
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Piret, SE, Gorvin, CM, Pagnamenta, AT, Howles, SA, Cranston, T, Rust, N, Nesbit, MA, Glaser, B, Taylor, JC, Buchs, AE, Hannan, F, and Thakker, RV
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Autosomal dominant hypocalcemia (ADH) is characterized by hypocalcemia, inappropriately low serum parathyroid hormone concentrations and hypercalciuria. ADH is genetically heterogeneous with ADH type 1 (ADH1), the predominant form, being caused by germline gain-of-function mutations of the G-protein coupled calcium-sensing receptor (CaSR), and ADH2 caused by germline gain-of-function mutations of G-protein subunit α-11 (Gα11 ). To date Gα11 mutations causing ADH2 have been reported in only five probands. We investigated a multi-generational non-consanguineous family, from Iran, with ADH and keratoconus which are not known to be associated, for causative mutations by whole-exome sequencing in two individuals with hypoparathyroidism, of whom one also had keratoconus, followed by cosegregation analysis of variants. This identified a novel heterozygous germline Val340Met Gα11 mutation in both individuals, and this was also present in the other 2 relatives with hypocalcemia that were tested. Three-dimensional modeling revealed the Val340Met mutation to likely alter the conformation of the C-terminal α5 helix, which may affect G-protein coupled receptor binding and G-protein activation. In vitro functional expression of wild-type (Val340) and mutant (Met340) Gα11 proteins in HEK293 cells stably expressing the CaSR, demonstrated that the intracellular calcium responses following stimulation with extracellular calcium, of the mutant Met340 Gα11 led to a leftward shift of the concentration-response curve with a significantly (p
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- 2016
16. Investigating hypocalcaemia
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Hannan, F. M., primary and Thakker, R. V., additional
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- 2013
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17. Associations between single-nucleotide polymorphisms of ADIPOQ, serum adiponectin and increased type 2 diabetes mellitus risk in Bahraini individuals.
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Al Hannan, F. A., O'Farrell, P. A., Morgan, M. P., Tighe, O., and Culligan, K. G.
- Abstract
Copyright of Eastern Mediterranean Health Journal is the property of World Health Organization and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2016
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18. CHAPTER 3 - Molecular and Cellular Mechanisms of Learning Disabilities: A Focus on Neurofibromatosis Type I
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Shilyansky, Carrie, Li, Weidong, Acosta, M., Elgersma, Y., Hannan, F., Hardt, M., Hunter-Schaedle, K., Krab, L.C., Legius, E., Wiltgen, B., and Silva, Alcino J
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- 2008
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19. Identification of 70 calcium-sensing receptor mutations in hyper- and hypo-calcaemic patients: evidence for clustering of extracellular domain mutations at calcium-binding sites
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Hannan, F. M., primary, Nesbit, M. A., additional, Zhang, C., additional, Cranston, T., additional, Curley, A. J., additional, Harding, B., additional, Fratter, C., additional, Rust, N., additional, Christie, P. T., additional, Turner, J. J. O., additional, Lemos, M. C., additional, Bowl, M. R., additional, Bouillon, R., additional, Brain, C., additional, Bridges, N., additional, Burren, C., additional, Connell, J. M., additional, Jung, H., additional, Marks, E., additional, McCredie, D., additional, Mughal, Z., additional, Rodda, C., additional, Tollefsen, S., additional, Brown, E. M., additional, Yang, J. J., additional, and Thakker, R. V., additional
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- 2012
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20. The time of onset of inherited cataract
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BRON, AJ, primary, HANNAN, F, additional, MUSHTAQ, B, additional, and KORETZ, JF, additional
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- 2008
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21. Distinct Functional Domains of Neurofibromatosis Type 1 Regulate Immediate versus Long-Term Memory Formation
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Ho, I. S., primary, Hannan, F., additional, Guo, H.-F., additional, Hakker, I., additional, and Zhong, Y., additional
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- 2007
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22. A locust type 1 ADP-ribosylation factor (lARF1) * is 100% identical in amino acid sequence to Drosophila ARF1 despite obvious DNA sequence divergence
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Hannan, F., primary and Evans, P. D., additional
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- 2000
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23. Second Messenger Systems Underlying Plasticity at the Neuromuscular Junction
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HANNAN, F, primary and ZHONG, Y, additional
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- 1999
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24. PCR primer: A laboratory manual Edited by C. W. Dieffenbach and G. S. Dveksler, CSHL Press, 1995. US$95.00 (714 pages) ISBN 0 87969 448 3
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HANNAN, F, primary
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- 1996
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25. Cloning and characterization of a calcium channel alpha 1 subunit from Drosophila melanogaster with similarity to the rat brain type D isoform
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Zheng, W, primary, Feng, G, additional, Ren, D, additional, Eberl, DF, additional, Hannan, F, additional, Dubald, M, additional, and Hall, LM, additional
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- 1995
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26. The expression of a cloned Drosophila octopamine/tyramine receptor in Xenopus oocytes
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Reale, V., Hannan, F., Midgley, J. M., and Evans, P. D.
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- 1997
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27. Use of nicotinic acid in the management of recurrent hypoglycemic episodes in diabetes.
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Hannan, Fadil, Davoren, Peter, Hannan, F, and Davoren, P
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NIACIN ,HYPOGLYCEMIA treatment ,PEOPLE with diabetes ,DRUG efficacy ,BLOOD sugar ,CHRONIC diseases ,HYPOGLYCEMIA ,INSULIN ,TYPE 1 diabetes ,PANCREATITIS ,DISEASE relapse ,DISEASE complications ,THERAPEUTICS ,PREVENTION - Abstract
Reports the cases of two patients with long-standing poorly controlled diabetes in whom nicotinic acid (NA) has been used to decrease the occurrence of hypoglycemic episodes. Medical records of the patients; Response of the patients to NA treatment.
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- 2001
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28. P.S.
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HANNAN, F. J.
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- 1921
29. BALANCE AND STRENGTH CHANGES IN ELDERLY SUBJECTS AFTER HEAVYRESISTANCE STRENGTH TRAINING
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Parsons, Dorubeth, Foster, V., Hannan, F., Dickinson, A., Oliva, P., and Westerlind, K.
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- 1992
30. The role of AP2σ variants in calcitropic and non-calcitropic disorders
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Stokes, V, Hannan, F, Russell, G, Chatterjee, K, Rorsman, P, Thakker, R, Cox, R, Gorvin, C, Bayliss, A, and Stevenson, M
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Genetic disorders in children ,Signal transducing adaptor proteins ,Genetic disorders--Diagnosis ,Data sets ,Mouse models ,Genetic disorders ,Cell receptors - Abstract
The Adaptor Protein 2 (AP2) is a heterotetrameric complex comprising of α, β, μ and σ-subunits, and it has an integral role in clathrin-mediated endocytosis (CME). CME is the process by which plasma membrane constituents are internalised, and this is the major endocytic pathway in mammalian cells. Missense mutations of AP2σ (Arg15Cys, Arg15His and Arg15Leu) cause impaired internalisation of the calcium-sensing receptor (CaSR), a G-protein coupled receptor (GPCR), and lead to Familial Hypocalciuric Hypercalcaemia type 3 (FHH3), a condition associated with moderate to severe hypercalcaemia, which may be symptomatic and associated with low bone mineral density and pancreatitis. Patients with FHH3-associated mutations may also have non-calcitropic disorders, including neurodevelopmental disorders. This thesis aims to further explore the role of AP2σ variants in calcitropic and non-calcitropic disorders by studying large population datasets to search for novel AP2S1 variants; generating mutant mouse models of FHH3; and investigating the role of AP2σ mutations in neurodevelopmental disorders. My studies have identified 3 additional AP2S1 variants in humans, Thr112Met, Met117Ile and Glu142Lys, that affect intracellular calcium (Ca2+i) signalling in vitro. Clinical data was available for the Met117Ile only, and the patient had mild hypercalcaemia. The identification of these novel variants potentially increases the spectrum of known mutations in AP2S1, suggesting a change in practice to include exon 5 in addition to exon 2 when screening the gene in FHH patients, and demonstrates the utility of large-scale sequencing databases in identifying genetic variants. The heterozygote Ap2s1+/L15, Ap2s1+/C15 and Ap2s1+/I117 mice were viable and reached adulthood. However, the homozygote Ap2s1L15/L15 died in the early neonatal period, whilst the Ap2s1C15/C15 mice were subviable with significantly fewer mice surviving weaning and by adulthood, whereas the Ap2s1I117/I117 mice were viable and reached adulthood. The Ap2s1+/L15 and Ap2s1+/C15 mice had hypercalcaemia, with the hypercalcaemia being significantly greater in the Ap2s1+/L15 than the Ap2s1+/C15 mice. The homozygote Ap2s1L15/L15 and Ap2s1C15/C15 mice had significantly greater elevations in plasma calcium than their heterozygote counterparts. The Ap2s1+/I117 and Ap2s1I117/I117 mice did not have hypercalcaemia. In conclusion, my studies have expanded the phenotypic spectrum associated with AP2S1 mutations, and have also established Ap2s1 mouse models that will enable the evaluation of the roles of AP2σ in calcium homeostasis and endosomal trafficking of the CaSR through pathophysiological studies that are difficult to undertake in patients. The Ap2s1+/L15 and the Ap2s1+/C15 mutant mice represent models for human FHH3. Finally, I describe nine children with heterozygous variants of AP2S1 Arg10 in association with neurodevelopmental delay, thereby suggesting a wider role in non-calcitropic phenotype of AP2S1 mutations.
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- 2022
31. Molecular pathophysiology of the calcium-sensing receptor
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Babinsky, V, Thakker, R, and Hannan, F
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The calcium-sensing receptor (CaSR) is a parathyroid and kidney expressed G-protein-coupled receptor that regulates extracellular calcium (Ca2+o) homeostasis. The CaSR mainly couples to G-protein subunit-α11 (Gα11), and germline Gα11 mutations have recently been identified in patients with hypercalcaemia and hypocalcaemia. The CaSR is also expressed in non-Ca2+o-regulating tissues such as the vasculature and pancreatic islets, where it is implicated in vascular calcification and insulin secretion, respectively. The aims of the studies described in this thesis were to: 1) Functionally characterise Gα11 mutations and evaluate the effect of CaSR-targeted drugs in cells expressing mutant Gα11 proteins; 2) Investigate for associations between common CaSR single nucleotide polymorphisms (SNPs) and vascular calcification; 3) Determine whether the CaSR may influence systemic glucose homeostasis; and 4) Evaluate the effect of a CaSR-targeted allosteric modulator on glucose homeostasis. These studies demonstrated germline Gα11 mutations to influence the responsiveness of CaSR-expressing cells to Ca2+o in vitro, and these abnormalities were rectified by CaSR-targeted drugs. Moreover, patient-based studies revealed CaSR SNPs not to be major determinants for vascular calcification. However, a common CaSR SNP was significantly associated with serum glucose concentrations. Furthermore, metabolic studies of mice with a gain-of-function CaSR mutation, known as Nuf, revealed impaired glucose tolerance in association with reduced plasma insulin concentrations and diminished pancreatic islet mass. An examination of isolated Nuf islets demonstrated alterations in insulin and glucagon secretion. Administration of a negative allosteric CaSR modulator to Nuf mice significantly improved the impaired glucose tolerance in vivo. In summary, the in vitro, animal model and patient-based studies encompassed in this thesis have revealed the effectiveness of CaSR-targeted drugs in modulating alterations in downstream signalling proteins, demonstrated a role for the CaSR in pancreatic islet function and glucose homeostasis, and indicate a potential application of CaSR-targeted drugs in modulating glucose metabolism.
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- 2016
32. Jasmonic acid mediates Ca 2+ dependent signal transduction and plant immunity.
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Farooq MA, Ayyaz A, Zou HX, Zhou W, Hannan F, and Yan X
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- Animals, Plants metabolism, Plants immunology, Cyclopentanes metabolism, Oxylipins metabolism, Plant Immunity, Signal Transduction, Plant Growth Regulators metabolism, Calcium metabolism
- Abstract
Pathogen attacks can cause significant damage to plants, posing a threaten to global food production. Plants have developed exquisite methods to rapidly store a key defensive hormone jasmonate (JA), which stimulates their entire evolutionary adaptive response to pathogen attack. However, understanding how plants initiate JA biosynthesis in response to pathogen attacks has remained elusive. In this review, we discuss the newly discovered JAV1-JAZ8-WRKY51 (JJW) complex, which plays a crucial role in regulating JA production to deter insect attacks. The JJW complex inhibits JA production in plants, maintaining a low baseline level of JA that promotes optimal plant development. However, when plants are attacked by insects, a rapid influx of calcium stimulates the JAV1 calcium-dependent protein phosphate, leading to the breakdown of the JJW complex and the activation of JA production. This surge in JA levels, initiates plant defense mechanisms against the invading insects. These findings shed light on the intricate defense system that plants have evolved to combat diseases., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
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- 2024
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33. Chromium uptake and its impact on antioxidant level, photosynthetic machinery, and related gene expression in Brassica napus cultivars.
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Batool I, Ayyaz A, Zhang K, Hannan F, Sun Y, Qin T, Athar HUR, Naeem MS, Zhou W, and Farooq MA
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- Oxidative Stress, Reactive Oxygen Species metabolism, Chlorophyll metabolism, Gene Expression drug effects, Brassica napus genetics, Brassica napus metabolism, Brassica napus drug effects, Photosynthesis, Antioxidants metabolism, Chromium
- Abstract
The development of heavy metals, particularly chromium (Cr)-tolerant crop cultivars, is hampered due to lack of understanding of the mechanisms behind Cr stress tolerance. In this study, two Brassica napus cultivars, ZS758 and ZD622, were compared for Cr stress resistance by using the chlorophyll a fluorescence technique and biochemical characteristics. In both cultivars, Cr stress dramatically decreased PSII and PSI efficiency, biomass accumulation, and antioxidant enzyme levels. Although, cultivar ZS758 showed reduction in oxidative stress by decreasing the production of reactive oxygen species (ROS) in terms of reduced H
2 O2 and MDA content and increased enzymatic activities of key antioxidants enzymes including SOD, APX, CAT, and POD activities that play a crucial role in the regulation of numerous transcriptional pathways involved in oxidative stress responses. Higher non-photochemical quenching (NPQ) and QY were found in tolerant ZS758 cultivar under Cr stress, indicating that tolerant cultivar had a greater capacity to preserve PSII activity under Cr stress by enhancing heat dissipation as a photo-protective component of NPQ. Lower PSI activity and electron transfer from PSII were confirmed by lower PSI efficiency and higher donor end limitation of PSI in both rapeseed cultivars. The Cr concentration was greater in the ZD622 as compared to ZS758, which affected the mineral nutrients profile and damaged the cellular ultrastructure and related gene expression levels. However, current study suggest that cultivar ZS758 is more resistant to Cr stress than ZD622 due to improved metabolism and structural integrity and Cr stress tolerance that is linked with the increased PSII activity, NPQ, and antioxidant potential; these physiological characteristics can be exploited to select cultivars for Cr stress tolerance., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2024
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34. Functionality of wheat straw-derived biochar enhanced its efficiency for actively capping Cd and Pb in contaminated water and soil matrices: Insights through batch adsorption and flow-through experiments.
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Hamid Y, Chen Y, Lin Q, Haris M, Usman M, Saqib Rashid M, Anastopoulos I, Hussain B, Ali HM, Hannan F, Yin X, and Yang X
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- Adsorption, Charcoal chemistry, Cadmium chemistry, Triticum chemistry, Lead chemistry, Soil Pollutants chemistry, Soil Pollutants analysis, Water Pollutants, Chemical chemistry, Environmental Restoration and Remediation methods, Soil chemistry
- Abstract
The impact of functionality of biochar on pressing environmental issue of cadmium (Cd) and lead (Pb) co-contamination in simultaneous soil and water systems has not sufficiently reported. This study investigated the impact of Fe- and Mg-functionalized wheat straw biochar (Fe-WSBC and Mg-WSBC) on Cd and Pb adsorption/immobilization through batch sorption and column leaching trials. Importantly, Fe-WSBC was more effective in adsorbing Cd and Pb (82.84 and 111.24 mg g
-1 ), regeneration ability (removal efficiency 94.32 and 92.365), and competitive ability under competing cations (83.15 and 84.36%) compared to other materials (WSBC and Mg-WSBC). The practical feasibility of Fe-WSBC for spiked river water verified the 92.57% removal of Cd and 85.73% for Pb in 50 mg L-1 and 100 mg L-1 contamination, respectively. Besides, the leaching of Cd and Pb with Fe-WSBC under flow-through conditions was lowered to (0.326 and 17.62 mg L-1 ), respectively as compared to control (CK) (0.836 and 40.40 mg L-1 ). In short, this study presents the applicable approach for simultaneous remediation of contaminated water and soil matrices, offering insights into environmentally friendly green remediation strategies for heavy metals co-contaminated matrices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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35. Interactive mode of biochar-based silicon and iron nanoparticles mitigated Cd-toxicity in maize.
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Yasin MU, Hannan F, Munir R, Muhammad S, Iqbal M, Yasin I, Khan MSS, Kanwal F, Chunyan Y, Fan X, and Gan Y
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- Iron metabolism, Cadmium analysis, Zea mays metabolism, Silicon, Antioxidants metabolism, Charcoal chemistry, Soil chemistry, Nanoparticles toxicity, Nanoparticles chemistry, Oryza chemistry, Soil Pollutants analysis
- Abstract
Cadmium contamination poses severe environmental and health threats, necessitating effective mitigation strategies. Rice husk biochar (BC) and nanoparticle (NP) treatments are emerging strategies with limited research on their synergistic benefits. This study assesses BC, silicon NPs (nSi), and iron NPs (nFe) modifications (B-nSi, B-nFe, and B-nSi-nFe) to reduce Cd-bioavailability in soil and its toxicity in maize, not reported before. Characterization of amendments validated, nSi and nFe attachment to BC, forming new mineral crystals to adsorb Cd. We found that B-nSi-nFe induced Cd-immobilization in soil by the formation of Cd-ligand complexes with the effective retention of NPs within microporous structure of BC. B-nSi-nFe increased soil pH by 0.76 units while reducing bioavailable Cd by 49 %, than Ck-Cd. Resultantly, B-nSi-nFe reduced Cd concentrations in roots and shoots by 51 % and 75 %, respectively. Moreover, the application of B-nSi-nFe significantly enhanced plant biomass, antioxidant activities, and upregulated the expression of antioxidant genes [ZmAPX (3.28 FC), ZmCAT (3.20 FC), ZmPOD (2.58 FC), ZmSOD (3.08 FC), ZmGSH (3.17 FC), and ZmMDHAR (3.80 FC)] while downregulating Cd transporter genes [ZmNramp5 (3.65 FC), ZmHMA2 (2.92 FC), and ZmHMA3 (3.40 FC)] compared to Ck-Cd. Additionally, confocal microscopy confirmed the efficacy of B-nSi-nFe in maintaining cell integrity due to reduced oxidative stress. SEM and TEM observations revealed alleviation of Cd toxicity to stomata, guard cells, and ultracellular structures with B-nSi-nFe treatment. Overall, this study demonstrated the potential of B-nSi-nFe for reducing Cd mobility in soil-plant system, mitigating Cd-toxicity in plants and improving enzymatic activities in soil., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)
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- 2024
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36. Silicon dioxide nanoparticles enhance plant growth, photosynthetic performance, and antioxidants defence machinery through suppressing chromium uptake in Brassica napus L.
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Huang Q, Ayyaz A, Farooq MA, Zhang K, Chen W, Hannan F, Sun Y, Shahzad K, Ali B, and Zhou W
- Subjects
- Antioxidants metabolism, Silicon Dioxide, Hydrogen Peroxide pharmacology, Photosynthesis, Oxidative Stress, Chromium toxicity, Chromium analysis, Transcription Factors, Brassica napus, Nanoparticles toxicity, Soil Pollutants analysis
- Abstract
Chromium (Cr) is a highly toxic heavy metal that is extensively released into the soil and drastically reduces plant yield. Silicon nanoparticles (Si NPs) were chosen to mitigate Cr toxicity due to their ability to interact with heavy metals and reduce their uptake. This manuscript explores the mechanisms of Cr-induced toxicity and the potential of Si NPs to mitigate Cr toxicity by regulating photosynthesis, oxidative stress, and antioxidant defence, along with the role of transcription factors and heavy metal transporter genes in rapeseed (Brassica napus L.). Rapeseed plants were grown hydroponically and subjected to hexavalent Cr stress (50 and 100 μM) in the form of K
2 Cr2 O7 solution. Si NPs were foliar sprayed at concentrations of 50, 100 and 150 μM. The findings showed that 100 μM Si NPs under 100 μM Cr stress significantly increased the leaf Si content by 169% while reducing Cr uptake by 92% and 76% in roots and leaves, respectively. The presence of Si NPs inside the plant leaf cells was confirmed by using energy-dispersive spectroscopy, inductively coupled plasma‒mass spectrometry, and confocal laser scanning microscopy. The study's findings showed that Cr had adverse effects on plant growth, photosynthetic gas exchange attributes, leaf mesophyll ultrastructure, PSII performance and the activity of enzymatic and nonenzymatic antioxidants. However, Si NPs minimized Cr-induced toxicity by reducing total Cr accumulation and decreasing oxidative damage, as evidenced by reduced ROS production (such as H2 O2 and MDA) and increased enzymatic and nonenzymatic antioxidant activities in plants. Interestingly, Si NPs under Cr stress effectively increased the NPQ, ETR and QY of PSII, indicating a robust protective response of PSII against stress. Furthermore, the enhancement of Cr tolerance facilitated by Si NPs was linked to the upregulation of genes associated with antioxidant enzymes and transcription factors, alongside the concurrent reduction in metal transporter activity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)- Published
- 2024
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37. Phytomelatonin: A key regulator of redox and phytohormones signaling against biotic/abiotic stresses.
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Khan MSS, Ahmed S, Ikram AU, Hannan F, Yasin MU, Wang J, Zhao B, Islam F, and Chen J
- Subjects
- Plants genetics, Stress, Physiological genetics, Oxidation-Reduction, Plant Growth Regulators metabolism, Melatonin pharmacology, Melatonin metabolism
- Abstract
Plants being sessile in nature, are exposed to unwarranted threats as a result of constantly changing environmental conditions. These adverse factors can have negative impacts on their growth, development, and yield. Hormones are key signaling molecules enabling cells to respond rapidly to different external and internal stimuli. In plants, melatonin (MT) plays a critical role in the integration of various environmental signals and activation of stress-response networks to develop defense mechanisms and plant resilience. Additionally, melatonin can tackle the stress-induced alteration of cellular redox equilibrium by regulating the expression of redox hemostasis-related genes and proteins. The purpose of this article is to compile and summarize the scientific research pertaining to MT's effects on plants' resilience to biotic and abiotic stresses. Here, we have summarized that MT exerts a synergistic effect with other phytohormones, for instance, ethylene, jasmonic acid, and salicylic acid, and activates plant defense-related genes against phytopathogens. Furthermore, MT interacts with secondary messengers like Ca
2+ , nitric oxide, and reactive oxygen species to regulate the redox network. This interaction triggers different transcription factors to alleviate stress-related responses in plants. Hence, the critical synergic role of MT with diverse plant hormones and secondary messengers demonstrates phytomelatonin's importance in influencing multiple mechanisms to contribute to plant resilience against harsh environmental factors., Competing Interests: Declaration of competing interest All authors declare no conflict of interests., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2023
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38. Corrigendum to "OsLPXC negatively regulates tolerance to cold stress via modulating oxidative stress, antioxidant defense and JA accumulation in rice" [Free Radic. Biol. Med. 199 (2023) 2-16].
- Author
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Islam F, Khan MSS, Ahmed S, Abdullah M, Hannan F, and Chen J
- Published
- 2023
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39. OsLPXC negatively regulates tolerance to cold stress via modulating oxidative stress, antioxidant defense and JA accumulation in rice.
- Author
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Islam F, Khan MSS, Ahmed S, Abdullah M, Hannan F, and Chen J
- Subjects
- Reactive Oxygen Species metabolism, Cold-Shock Response, Oxidative Stress, Gene Expression Regulation, Plant, Cold Temperature, Antioxidants metabolism, Oryza genetics, Oryza metabolism
- Abstract
Exposure of crops to low temperature (LT) during emerging and reproductive stages influences their growth and development. In this study, we have isolated a cold induced, nucleus-localized lipid A gene from rice named OsLPXC, which encodes a protein of 321 amino acids. Knockout of OsLPXC resulted in enhance sensitivity to LT stress in rice, with increased accumulation of reactive oxygen species (ROS), malondialdehyde and electrolyte leakage, while expression and activities of antioxidant enzymes were significantly suppressed. The accumulation of chlorophyll content and net photosynthetic rate of knockout plants were also decreased compared with WT under LT stress. The functional analysis of differentially expressed genes (DEGs), showed that numerous genes associated with antioxidant defense, photosynthesis, cold signaling were solely expressed and downregulated in oslpxc plants compared with WT under LT. The accumulation of methyl jasmonate (MeJA) in leave and several DEGs related to the jasmonate biosynthesis pathway were significantly downregulated in OsLPXC knockout plants, which showed differential levels of MeJA regulation in WT and knockout plants in response to cold stress. These results indicated that OsLPXC positively regulates cold tolerance in rice via stabilizing the expression and activities of ROS scavenging enzymes, photosynthetic apparatus, cold signaling genes, and jasmonate biosynthesis., (Copyright © 2023 Elsevier Inc. All rights reserved.)
- Published
- 2023
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40. Calcium nanoparticles (Ca-NPs) improve drought stress tolerance in Brassica napus by modulating the photosystem II, nutrient acquisition and antioxidant performance.
- Author
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Ayyaz A, Fang R, Ma J, Hannan F, Huang Q, Athar HU, Sun Y, Javed M, Ali S, Zhou W, and Farooq MA
- Subjects
- Calcium, Antioxidants pharmacology, Hydrogen Peroxide, Photosystem II Protein Complex, Brassica napus
- Abstract
Foliar-application of nano-particles enhanced the foliar nutrient status and crop growth and yield. It is hypothesized that being second messenger molecule, supplementation of Ca
2+ via calcium nanoparticles (Ca-NPs) can trigger various signaling pathways of physiological processes which can lead to alleviate the adverse effects of drought stress on the growth of canola (Brassica napus L.). Nano-enabled foliar-application could be an ideal strategy for advancing agricultural productivity. The present study explored the role of calcium nanoparticles (Ca-NPs) in alleviating drought stress in hydroponic Brassica napus (B. napus) plants. The foliar applied Ca-NPs were spherically shaped with an average size of 86 nm. Foliar application of 100 mg L-1 Ca-NPs enhanced biomass of canola plants and considered as optimal dose. Ca-NPs at 100 mg L-1 has a greater favorable impact on mesophyll ultrastructure, PSI and PSII efficacy, gas exchange parameters, chlorophyll content, and mineral absorption. The Ca-NPs treatment increased NPQ and Y(NPQ) under drought condition, indicating a higher PSII protective response to stressed conditions with better heat dissipation as a photoprotective component of NPQ. Ca-NPs application also reduced oxidative stress damage as measured by a reduction in reactive oxygen species (ROS) generation in terms of hydrogen peroxide and malondialdehyde (H2 O2 and MDA). Furthermore, Ca-NPs induced drought tolerance response corresponded to an increased in key antioxidative defense enzymes (SOD, POD, CAT, APX), as well as non-enzymatic components (protease, lipoxygenase, proline, total soluble protein contents, endogenous hormonal biosynthesis), and secondary metabolite expression in B. napus plants. Taken together, the results of this study offer new insights into the physiological and molecular mechanisms by which B. napus responds to Ca-NPs exposure., Competing Interests: Declaration of Competing Interest Authors declared there is no conflict of interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2022
- Full Text
- View/download PDF
41. Purple stem Brassica napus exhibits higher photosynthetic efficiency, antioxidant potential and anthocyanin biosynthesis related genes expression against drought stress.
- Author
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Chen W, Miao Y, Ayyaz A, Hannan F, Huang Q, Ulhassan Z, Zhou Y, Islam F, Hong Z, Farooq MA, and Zhou W
- Abstract
Purple-stem Brassica napus ( B. napus ) is a phenotype with unique color because of its high anthocyanins content. Anthocyanins are naturally occurring plant pigments that have antioxidants activity and play important role in plant defense against abiotic and biotic stresses. In the present study, drought induced effects on plants were investigated in hydroponically grown seedlings of green stem (GS) and purple stem (PS) genotypes of B. napus . The results of this study showed that the major function of anthocyanins accumulation during drought was to enhance the antioxidant capability and stress tolerance in B. napus plants. Our results showed that drought significantly inhibited the plant growth in terms of decreased biomass accumulation in both genotypes, although marked decline was observed in GS genotype. The reduction in photosynthetic attributes was more noticeable in the GS genotype, whereas the PS genotype showed better performance under drought stress. Under stressful conditions, both the genotype showed excessive accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA), as well as higher levels of antioxidant enzymes activities. Under drought conditions, the GS genotype showed apparent damages on chloroplast deformation like in thylakoid membrane and grana structural distortion and fewer starch grains and bigger plastoglobuli. Moreover, during drought stress, the PS genotype exhibited maximum expression levels of anthocyanins biosynthesis genes and antioxidant enzymes accompanied by higher stress tolerance relative to GS genotype. Based on these findings, it can be concluded that GS genotype found more sensitive to drought stress than the PS genotype. Furthermore this research paper also provides practical guidance for plant biologists who are developing stress-tolerant crops by using anthocyanin biosynthesis or regulatory genes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Chen, Miao, Ayyaz, Hannan, Huang, Ulhassan, Zhou, Islam, Hong, Farooq and Zhou.)
- Published
- 2022
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42. Mitigation effects of exogenous melatonin-selenium nanoparticles on arsenic-induced stress in Brassica napus.
- Author
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Farooq MA, Islam F, Ayyaz A, Chen W, Noor Y, Hu W, Hannan F, and Zhou W
- Subjects
- Hydrogen Peroxide, Arsenic toxicity, Brassica napus, Melatonin, Nanoparticles, Selenium
- Abstract
Melatonin (MT) and selenium (Se) application known to decrease heavy metal uptake and toxicity in plants. By mixing the Se in MT medium a new complex MT-Se nanoparticles (MT-Se NPs) was synthesized and we investigated the role of MT-Se NPs on B. napus growth and tolerance against As stress. The MT-Se particles significantly enhanced the plant growth and other associated physiological attributes under As stress. The As treatment at 80 μM was more phytotoxic, however MT-Se NPs application resulted in a substantial increase in leaf chlorophyll fluorescence, biomass accumulation, and decreased ROS relative to As stressed plants. The use of MT-Se NPs to As stressed plants reduced photosynthetic inhibition and oxidative stress and attenuated the increase in MDA and H
2 O2 contents. The application of MT-Se NPs also boosted the antioxidant enzymes activities such as SOD, POD and CAT as well as the APX, GR and GSH activates under As stress. The results also showed MT-Se NPs treatments alleviated the growth inhibition induced by As and reduced the accumulation of As in leaves and roots of B. napus seedlings. Moreover, treatment with MT-Se NPs improved the plant growth more successfully than treatment of MT and Se alone. This study explored the mechanism of melatonin and selenium efficiency in the composition can be jointly encouraged to exert synergistic effects and boost plant enzymatic activities., (Copyright © 2021 Elsevier Ltd. All rights reserved.)- Published
- 2022
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43. Interactive effects of biochar and mussel shell activated concoctions on immobilization of nickel and their amelioration on the growth of rapeseed in contaminated aged soil.
- Author
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Hannan F, Islam F, Huang Q, Farooq MA, Ayyaz A, Fang R, Ali B, Xie X, and Zhou W
- Subjects
- Animals, Charcoal, Nickel analysis, Nickel toxicity, Soil, Bivalvia, Brassica napus, Soil Pollutants analysis, Soil Pollutants toxicity
- Abstract
Mussel shell (MS) and biochar (BC) are commonly used for the remediation of metal contaminated soil. However, less research has been focused to examine the efficacy of their combinations to reduce metal toxicity in crop plants. This study was therefore conducted to investigate the effects of BC, MS and their activated concoctions on the soil properties, enzyme activities and nickel (Ni) immobilization in aged Ni contaminated soil. Moreover, the growth, photosynthetic pigments and anti-oxidative machnery of Brassica napus plants has also been investigated in order to determine amendments efficiency in reducing soil Ni toxicity for plants. The results showed that the application of Ni adversely affected soil health and trigged stress responses by inducing oxidative stress in B. napus. However, the incorporation of amendments reduced the bioavailability of Ni, and the concoctions of BC and MS showed promising results in the immobilization of Ni. Among various combinations of BC and MS, treatment with BC + MS (3:1) significantly reduced Ni uptake, decreased reactive oxygen species (ROS) and enhanced antioxidant defense of B. napus plants. Results showed that amendment's combinations stimulated the transcriptional levels of ROS scavenging enzymes and suppressed the expression level of Ni transporters. The morphological and physical characterization techniques (i.e. SEM, BET, EDS, FTIR and X-ray diffraction analyses) showed that amendment's combinations had relatively higher Ni adsorption capacity, indicating that BC and MS concoctions are efficient immobilizing agents for minimizing Ni availability, preventing oxidative toxicity and promoting growth and biomass production in rapeseed plants under metal stress conditions., (Copyright © 2021 Elsevier Ltd. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
44. Organic and inorganic amendments for the remediation of nickel contaminated soil and its improvement on Brassica napus growth and oxidative defense.
- Author
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Hannan F, Huang Q, Farooq MA, Ayyaz A, Ma J, Zhang N, Ali B, Deyett E, Zhou W, and Islam F
- Subjects
- Charcoal, Hydrogen Peroxide, Nickel analysis, Oxidative Stress, Soil, Brassica napus, Soil Pollutants analysis
- Abstract
In-situ stabilization has been considered an effective way to remediate metal contaminated soil. Thus, pot experiments were undertaken to investigate the effectiveness of multiple stabilization agents such as biochar (BC), mussel shell (MS), zeolite (ZE) and limestone (LS) on the immobilization of Ni, physicochemical features and enzyme activities in polluted soil. Results showed that the sole application of Ni adversely affected the rapeseed growth, photosynthetic pigments, and antioxidative defense. However, the addition of amendments to the contaminated soil significantly reduced Ni bioavailability. The XRD analysis confirmed the formation of Ni related ligands and FTIR showed the presence of hydroxyl, carboxyl and sulfur functional groups, as well as complexation and adsorption of Ni on amendments. Among multiple amendments, biochar significantly enhanced plant biomass attributes and total chlorophyll content. Moreover, addition of amendments also strengthened the antioxidant defense by decreasing Ni induced oxidative stress (H
2 O2 and O2 .- ), increased macronutrient availability, reduced Ni uptake and improved soil health. The qPCR analysis showed that the Ni transporters were significantly suppressed by amendments, which is correlated with the lower accumulation of Ni in rapeseed. The present study showed that immobilizing agents, especially biochar, is an effective amendment to immobilize Ni in soil, which restricts its entry into the food chain., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2021
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45. Drought tolerance in Brassica napus is accompanied with enhanced antioxidative protection, photosynthetic and hormonal regulation at seedling stage.
- Author
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Ayyaz A, Miao Y, Hannan F, Islam F, Zhang K, Xu J, Farooq MA, and Zhou W
- Subjects
- Antioxidants, Droughts, Photosynthesis, Seedlings, Brassica napus
- Abstract
Climate change, food insecurity, water scarcity, and population growth are some of today's world's frightening problems. Drought stress exerts a constant threat to field crops and is often seen as a major constraint on global agricultural productivity; its intensity and frequency are expected to increase in the near future. The present study investigated the effects of drought stress (15% w/v polyethylene glycol PEG-6000) on physiological and biochemical changes in five Brassica napus cultivars (ZD630, ZD622, ZD619, GY605, and ZS11). For drought stress induction, 3-week-old rapeseed oil seedlings were treated with PEG-6000 in full strength Hoagland nutrient solution for 7 days. PEG treatment significantly decreased the plant growth and photosynthetic efficiency, including primary photochemistry (Fv/Fm) of PSII, intercellular CO
2 , net photosynthesis, chlorophyll contents, and water-use efficiency of all studied B. napus cultivars; however, pronounced growth retardations were observed in cultivar GY605. Drought-stressed B. napus cultivars also experienced a sharp rise in H2 O2 generation and malondialdehyde (MDA) content. Additionally, the accumulation of ROS was accompanied by increased activity of enzymatic antioxidants (superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, glutathione reductase, and monodehydroascorbate reductase), although the increase was more obvious in ZD622 and ZS11. Drought stress also caused an increased endogenous hormonal biosynthesis (abscisic acid, jasmonic acid, salicylic acid) and accumulation of total soluble proteins and proline content, but the extent varies in B. napus cultivars. These results suggest that B. napus cultivars have an efficient drought stress tolerance mechanism, as shown by improved antioxidant enzyme activities, photosynthetic and hormonal regulation., (© 2021 Scandinavian Plant Physiology Society.)- Published
- 2021
- Full Text
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46. The edge effect: A global problem. The trouble with culturing cells in 96-well plates.
- Author
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Mansoury M, Hamed M, Karmustaji R, Al Hannan F, and Safrany ST
- Abstract
Background: The use of 96-well plates is ubiquitous in preclinical studies. Corner and edge wells have been observed to be more prone to evaporation compared to interior wells., Methods: Mammalian cells were cultured in 96-well plates over a period of 72 h. VWR and Greiner plates were tested. MTS reagent was added, and metabolic activity was determined after 2 h., Results: When using VWR plates, cells showed a highly heterogeneous pattern of cell growth. The outer wells showed 35% lower metabolic activity than the central wells. Cells grown in rows two and three also grew sub-optimally (25% and 10% reduction compared to central wells). Greiner plates showed better homogeneity. Cells grown in the outer wells showed 16% lower metabolic activity while cells in rows two and three showed reductions of 7 and 1%, respectively. This edge effect was partially mitigated by storing the plates in loosely sealed wrapping during incubation. Placing a buffer between the wells of the plate further improved homogeneity for the Greiner plates., Conclusion: Different brands of 96-well plates show different levels of the edge effect. Some clearly are inappropriate for such studies., General Significance: Each laboratory needs to determine their own optimum conditions for culturing cells empirically before continuing to use multiwell plates. Otherwise, large artifacts may arise, affecting the quality of data, with the potential of introducing type I or type II errors., Competing Interests: This research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2021 The Authors. Published by Elsevier B.V.)
- Published
- 2021
- Full Text
- View/download PDF
47. Comprehensive proteomic analysis of arsenic induced toxicity reveals the mechanism of multilevel coordination of efficient defense and energy metabolism in two Brassica napus cultivars.
- Author
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Farooq MA, Hong Z, Islam F, Noor Y, Hannan F, Zhang Y, Ayyaz A, Mwamba TM, Zhou W, and Song W
- Subjects
- Arsenic metabolism, Energy Metabolism, Gene Expression Regulation, Plant, Plant Proteins metabolism, Proteomics methods, Arsenic toxicity, Brassica napus drug effects, Proteome metabolism
- Abstract
Arsenic (As) a non-essential element is of particular concern with respect to harmful effects on plant metabolism. While extensive studies have been conducted on the physiological responses of plants to increase As concentrations, however, molecular differences elucidating species-specific changes remain largely unknown. In the present experiment, two oilseed Brassica napus (B. napus) cultivars, ZS758 and ZD622, were treated by elevated As concentration. Their responses to the As stress have been investigated through pulse amplitude modulated fluorometer and isobaric tags based proteomic (iTRAQ) analysis. The chlorophyll fluorescence attributes showed that As stress significantly decrease the photochemical efficiency of photosystem II (PSII) and photosystem I (PSI) as well as the comparatively closed stomata observed under scanning electron microscopy (SEM). In this study, 65 proteins displayed increased abundance and 52 down-regulated were found in the control vs As comparison in cultivar ZS758, while 44 up and 67 down-regulated proteins were found in the control vs As comparison in ZD622. Metabolic pathways, followed by ribosome and biosynthesis of secondary metabolites were the dominant functional annotation categories among the differentially expressed protein (DEPs). Many genes involved in primary metabolism, stress and defense were found to be As-responsive DEPs and/or DEPs between these two cultivars. Based on these results, a schematic description of key processes involved in As tolerance in ZS758 and ZD622 is proposed, which suggests that higher tolerance in ZS758 depends on a multilevel coordination of efficient defense and energy metabolism. Real-time quantitative PCR supported the expression patterns of several genes encoding a protein similar to their corresponding DEPs. In addition, these findings could shed light in unraveling the molecular mechanisms of B. napus exposed to As stress and provide or improve essential understandings in the development of advanced B. napus cultivars against As resistance., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2021
- Full Text
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48. Ursolic Acid Limits Salt-Induced Oxidative Damage by Interfering With Nitric Oxide Production and Oxidative Defense Machinery in Rice.
- Author
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Long M, Shou J, Wang J, Hu W, Hannan F, Mwamba TM, Farooq MA, Zhou W, and Islam F
- Abstract
Crops frequently encounter abiotic stresses, and salinity is a prime factor that suppresses plant growth and crop productivity, globally. Ursolic acid (UA) is a potential signaling molecule that alters physiology and biochemical processes and activates the defense mechanism in numerous animal models; however, effects of UA in plants under stress conditions and the underlying mechanism of stress alleviation have not been explored yet. This study examined the effects of foliar application of UA (100 μM) to mitigate salt stress in three rice cultivars (HZ, 712, and HAY). A pot experiment was conducted in a climate-controlled greenhouse with different salt stress treatments. The results indicated that exposure to NaCl-induced salinity reduces growth of rice cultivars by damaging chlorophyll pigment and chloroplast, particularly at a higher stress level. Application of UA alleviated adverse effects of salinity by suppressing oxidative stress (H
2 O2 , O2- ) and stimulating activities of enzymatic and non-enzymatic antioxidants (APX, CAT, POD, GR, GSH, AsA, proline, glycinebutane), as well as protecting cell membrane integrity (MDA, LOX, EL). Furthermore, UA application brought about a significant increase in the concentration of leaf nitric oxide (NO) by modulating the expression of NR and NOS enzymes. It seems that UA application also influenced Na+ efflux and maintained a lower cytosolic Na+ /K+ ratio via concomitant upregulation of OsSOS1 and OsHKT1;5 in rice cultivars. The results of pharmacological tests have shown that supply of the NO scavenger (PTI) completely reversed the UA-induced salt tolerance in rice cultivars by quenching endogenous NO and triggering oxidative stress, Na+ uptake, and lipid peroxidation. The PTI application with UA and sodium nitroprusside (SNP) also caused growth retardation and a significant increase in Na+ uptake and oxidative stress in rice cultivars. This suggests that UA promoted salt tolerance of rice cultivars by triggering NO production and limiting toxic ion and reactive oxygen species (ROS) accumulation. These results revealed that both UA and NO are together required to develop a salt tolerance response in rice., (Copyright © 2020 Long, Shou, Wang, Hu, Hannan, Mwamba, Farooq, Zhou and Islam.)- Published
- 2020
- Full Text
- View/download PDF
49. Characterization of BRCA1 and BRCA2 genetic variants in a cohort of Bahraini breast cancer patients using next-generation sequencing.
- Author
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Al Hannan F, Keogh MB, Taha S, and Al Buainain L
- Subjects
- Adult, Bahrain, Breast Neoplasms pathology, Codon, Nonsense, Female, Genetic Predisposition to Disease, Heterozygote, High-Throughput Nucleotide Sequencing, Humans, Mutation, Missense, RNA Splice Sites, BRCA1 Protein genetics, BRCA2 Protein genetics, Breast Neoplasms genetics
- Abstract
Background: Breast cancer is the most common malignancy in women worldwide. About 5%-10% are due to hereditary predisposition. The contribution of BRCA1/2 mutations to familial breast cancer in Bahrain has not been explored. The objective of this study was to investigate the spectrum of BRCA1/2 genetic variants and estimate their frequencies in familial breast cancer. We also aim to test the efficiency of the next-generation sequencing (NGS) as a powerful tool for detecting genetic variation within BRCA1/2 genes., Methods: Twenty-five unrelated female patients diagnosed with familial breast cancer were screened for BRCA1/2 variants. All targeted coding exons and exon-intron boundaries of BRCA1/2 genes were amplified with 167 pairs of primers by NGS., Results: We have identified two deleterious BRCA1/2 variants in two patients, one in BRCA1 gene (c.4850C>A) and other in BRCA2 gene (c.67+2T>C). In addition to the deleterious variants, we identified 24 distinct missense variants of uncertain significance, 10 of them are seen to confer minor but cumulatively significant risk of breast cancer., Conclusion: Our data suggest that BRCA1/2 variants may contribute to the pathogenesis of familial breast cancer in Bahrain. It also shows that NGS is useful tool for screening BRCA1/2 genetic variants of probands and unaffected relatives., (© 2019 RCSI BAHRAIN. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.)
- Published
- 2019
- Full Text
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50. Effect of biochar on cadmium bioavailability and uptake in wheat (Triticum aestivum L.) grown in a soil with aged contamination.
- Author
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Abbas T, Rizwan M, Ali S, Zia-Ur-Rehman M, Farooq Qayyum M, Abbas F, Hannan F, Rinklebe J, and Sik Ok Y
- Subjects
- Biological Availability, Cadmium metabolism, Edible Grain chemistry, Oryza chemistry, Pakistan, Photosynthesis drug effects, Plant Leaves chemistry, Plant Roots chemistry, Soil Pollutants metabolism, Triticum metabolism, Cadmium analysis, Charcoal chemistry, Soil chemistry, Soil Pollutants analysis, Triticum chemistry
- Abstract
Cadmium (Cd) is a well-known and widespread toxic heavy metal while the effects of biochar (BC) on Cd bioavailability and toxicity in wheat, especially in soils with aged contamination are largely unknown. In the present study, the effect of rice straw BC on Cd immobilization in soil and uptake by wheat in an agricultural contaminated-soil was investigated. Different levels of rice straw BC (0%, 1.5%, 3.0% and 5% w/w) were incorporated into the soil and incubated for two weeks. After this, wheat plants were grown in the amended soil until maturity. The results show that the BC treatments increased the soil and soil solution pH and silicon contents in the plant tissues and in the soil solution while decreased the bioavailable Cd in soil. The BC application increased the plant-height, spike-length, shoot and root dry mass and grain yield in a dose additive manner when compared with control treatment. As compared to control, BC application increased the photosynthetic pigments and gas exchange parameters in leaves. Biochar treatments decreased the oxidative stress while increased the activities of antioxidant enzymes in shoots compared to the control. The BC treatments decreased the Cd and Ni while increased Zn and Mn concentrations in shoots, roots, and grains of wheat compared to the control. As compared to the control, Cd concentration in wheat grains decreased by 26%, 42%, and 57% after the application of 1.5%, 3.0%, and 5.0% BC respectively. Overall, the application of rice straw BC might be effective in immobilization of metal in the soil and reducing its uptake and translocation to grains., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
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