1
|
Estrogens Regulate Placental Angiogenesis in Horses. Int J Mol Sci 2021; 22:ijms222212116. [PMID: 34829994 PMCID: PMC8621320 DOI: 10.3390/ijms222212116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 10/28/2021] [Accepted: 11/03/2021] [Indexed: 12/14/2022] Open
Abstract
A sufficient vascular network within the feto-maternal interface is necessary for placental function. Several pregnancy abnormalities have been associated with abnormal vascular formations in the placenta. We hypothesized that growth and expansion of the placental vascular network in the equine (Equus caballus) placenta is regulated by estrogens (estrogen family hormones), a hormone with a high circulating concentration during equine gestation. Administration of letrozole, a potent and specific inhibitor of aromatase, during the first trimester (D30 to D118), decreased circulatory estrone sulfate concentrations, increased circulatory testosterone and androstenedione concentrations, and tended to reduce the weight of the fetus (p < 0.1). Moreover, the gene expression of CYP17A1 was increased, and the expression of androgen receptor was decreased in the D120 chorioallantois (CA) of letrozole-treated mares in comparison to that of the control mares. We also found that at D120, the number of vessels tended to decrease in the CAs with letrozole treatment (p = 0.07). In addition, expression of a subset of angiogenic genes, such as ANGPT1, VEGF, and NOS2, were altered in the CAs of letrozole-treated mares. We further demonstrated that 17β-estradiol increases the expression of ANGPT1 and VEGF and increases the angiogenic activity of equine endothelial cells in vitro. Our results from the estrogen-suppressed group demonstrated an impaired placental vascular network, suggesting an estrogen-dependent vasculogenesis in the equine CA during the first trimester.
Collapse
|
2
|
Zhao X, Li X, Liu P, Li P, Xu X, Chen Y, Cheng Y, Zhu D, Fu X. 17β-estradiol promotes angiogenesis through non-genomic activation of Smad1 signaling in endometriosis. Vascul Pharmacol 2021; 142:106932. [PMID: 34763099 DOI: 10.1016/j.vph.2021.106932] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 09/24/2021] [Accepted: 11/04/2021] [Indexed: 12/19/2022]
Abstract
17β-estradiol (E2) plays a key role in endometriosis through regulation of angiogenesis. Smad1 has been reported to be up-regulated in patients with endometriosis. However, the role of Smad1 in E2-mediated angiogenesis during the development of endometriosis remains to be determined. This study aimed to explore the role of Smad1 in E2-mediated angiogenesis during endometriosis and its underlying mechanisms. Immunofluorescence staining and Western blotting were performed to examine the expression of p-Smad1 in ectopic and control endometrium. Western blotting was used to examine activation of Smad1 signaling in NMECs, EMECs and HUVECs. Tube formation assay was performed to examine the effect of E2 on angiogenesis. Cell proliferation and migration was determined using in real-time by xCELLigence RTCA DP instrument. We found that the expression of p-Smad1 was significantly up-regulated in ectopic endometrium and ectopic intima microvascular endothelial cells. E2 non-genomically stimulated phosphorylation of Smad1 in HUVECs. c-Src and p44/42 MAPK(ERK1/2) signaling pathways are required for E2's induction on Smad1 phosphorylation. Moreover, caveolae is involved in E2-induced Smad1 phosphorylation in vascular endothelial cells. E2 promoted tube formation of vascular endothelial cells through c-Src/ERK1/2/Smad1 signaling pathway. Knockdown of Smad1 expression attenuated E2-induced proliferation and migration of HUVECs. In conclusion, E2 promotes proliferation, migration and tube formation of HUVECs through c-Src/ERK1/2/Smad1 signaling pathway. Our data shed new lights on the mechanisms through which E2 contributes to endometriosis, and may provide novel strategies to treat endometriosis.
Collapse
Affiliation(s)
- Xinran Zhao
- Guangzhou Institute of Cardiovascular Disease, Guangdong Key Laboratory of Vascular Diseases, State Key Laboratory of Respiratory Disease, the Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong 510260, PR China; Department of Anesthesiology, The Third Affiliated Hospital of Southern Medical University, Guangzhou City, Guangdong Province, 510630, China
| | - Xiaosa Li
- Guangzhou Institute of Cardiovascular Disease, Guangdong Key Laboratory of Vascular Diseases, State Key Laboratory of Respiratory Disease, the Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong 510260, PR China; Department of Gynecology and Obstetrics, Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Key Laboratory of Cardiovascular Diseases, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou 511518, PR China
| | - Pei Liu
- Guangzhou Institute of Cardiovascular Disease, Guangdong Key Laboratory of Vascular Diseases, State Key Laboratory of Respiratory Disease, the Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong 510260, PR China; Department of Anesthesiology, The Third Affiliated Hospital of Southern Medical University, Guangzhou City, Guangdong Province, 510630, China
| | - Ping Li
- Guangzhou Institute of Cardiovascular Disease, Guangdong Key Laboratory of Vascular Diseases, State Key Laboratory of Respiratory Disease, the Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong 510260, PR China
| | - Xingyan Xu
- Guangzhou Institute of Cardiovascular Disease, Guangdong Key Laboratory of Vascular Diseases, State Key Laboratory of Respiratory Disease, the Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong 510260, PR China
| | - Yiwen Chen
- Guangzhou Institute of Cardiovascular Disease, Guangdong Key Laboratory of Vascular Diseases, State Key Laboratory of Respiratory Disease, the Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong 510260, PR China
| | - Yang Cheng
- Department of Gynecology and Obstetrics, Municipal First People's Hospital of Guangzhou, Guangzhou 510180, PR China.
| | - Dongxing Zhu
- Guangzhou Institute of Cardiovascular Disease, Guangdong Key Laboratory of Vascular Diseases, State Key Laboratory of Respiratory Disease, the Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong 510260, PR China.
| | - Xiaodong Fu
- Guangzhou Institute of Cardiovascular Disease, Guangdong Key Laboratory of Vascular Diseases, State Key Laboratory of Respiratory Disease, the Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong 510260, PR China.
| |
Collapse
|
3
|
Dini P, Carossino M, Balasuriya UBR, El-Sheikh Ali H, Loux SC, Esteller-Vico A, Scoggin KE, Loynachan AT, Kalbfleisch T, De Spiegelaere W, Daels P, Ball BA. Paternally expressed retrotransposon Gag-like 1 gene, RTL1, is one of the crucial elements for placental angiogenesis in horses†. Biol Reprod 2021; 104:1386-1399. [PMID: 33693478 DOI: 10.1093/biolre/ioab039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 12/08/2020] [Accepted: 03/03/2021] [Indexed: 11/15/2022] Open
Abstract
RTL1 (retrotransposon Gag-like 1) is an essential gene in the development of the human and murine placenta. Several fetal and placental abnormalities such as intrauterine growth restriction (IUGR) and hydrops conditions have been associated with altered expression of this gene. However, the function of RTL1 has not been identified. RTL1 is located on a highly conserved region in eutherian mammals. Therefore, the genetic and molecular analysis in horses could hold important implications for other species, including humans. Here, we demonstrated that RTL1 is paternally expressed and is localized within the endothelial cells of the equine (Equus caballus) chorioallantois. We developed an equine placental microvasculature primary cell culture and demonstrated that RTL1 knockdown leads to loss of the sprouting ability of these endothelial cells. We further demonstrated an association between abnormal expression of RTL1 and development of hydrallantois. Our data suggest that RTL1 may be essential for placental angiogenesis, and its abnormal expression can lead to placental insufficiency. This placental insufficiency could be the reason for IUGR and hydrops conditions reported in other species, including humans.
Collapse
Affiliation(s)
- Pouya Dini
- Department of Veterinary Medical Imaging and Small Animal Orthopaedics, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.,Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - Mariano Carossino
- Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - Udeni B R Balasuriya
- Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - Hossam El-Sheikh Ali
- Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA.,Theriogenology Department, Faculty of Veterinary Medicine, University of Mansoura, Mansoura, Egypt
| | - Shavahn C Loux
- Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - Alejandro Esteller-Vico
- Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - Kirsten E Scoggin
- Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - Alan T Loynachan
- Veterinary Diagnostic Laboratory, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - Theodore Kalbfleisch
- Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - Ward De Spiegelaere
- Department of Morphology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Peter Daels
- Department of Veterinary Medical Imaging and Small Animal Orthopaedics, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Barry A Ball
- Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| |
Collapse
|
4
|
da Silva JS, Montagnoli TL, Rocha BS, Tacco MLCA, Marinho SCP, Zapata-Sudo G. Estrogen Receptors: Therapeutic Perspectives for the Treatment of Cardiac Dysfunction after Myocardial Infarction. Int J Mol Sci 2021; 22:E525. [PMID: 33430254 PMCID: PMC7825655 DOI: 10.3390/ijms22020525] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/24/2020] [Accepted: 12/28/2020] [Indexed: 02/07/2023] Open
Abstract
Estrogen receptors (ER) mediate functions beyond their endocrine roles, as modulation of cardiovascular, renal, and immune systems through anti-inflammatory and anti-apoptotic effects, preventing necrosis of cardiomyocytes and endothelial cells, and attenuating cardiac hypertrophy. Estradiol (E2) prevents cardiac dysfunction, increases nitric oxide synthesis, and reduces the proliferation of vascular cells, yielding protective effects, regardless of gender. Such actions are mediated by ER (ER-alpha (ERα), ER-beta (ERβ), or G protein-coupled ER (GPER)) through genomic or non-genomic pathways, which regulate cardiovascular function and prevent tissue remodeling. Despite the extensive knowledge on the cardioprotective effects of estrogen, clinical studies conducted on myocardial infarction (MI) and cardiovascular diseases still include favorable and unfavorable profiles. The purpose of this review is to provide up-to-date information regarding molecular, preclinical, and clinical aspects of cardiovascular E2 effects and ER modulation as a potential therapeutic target for the treatment of MI-induced cardiac dysfunction.
Collapse
Affiliation(s)
- Jaqueline S. da Silva
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil; (J.S.d.S.); (T.L.M.); (B.S.R.); (M.L.C.A.T.); (S.C.P.M.)
| | - Tadeu L. Montagnoli
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil; (J.S.d.S.); (T.L.M.); (B.S.R.); (M.L.C.A.T.); (S.C.P.M.)
| | - Bruna S. Rocha
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil; (J.S.d.S.); (T.L.M.); (B.S.R.); (M.L.C.A.T.); (S.C.P.M.)
| | - Matheus L. C. A. Tacco
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil; (J.S.d.S.); (T.L.M.); (B.S.R.); (M.L.C.A.T.); (S.C.P.M.)
| | - Sophia C. P. Marinho
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil; (J.S.d.S.); (T.L.M.); (B.S.R.); (M.L.C.A.T.); (S.C.P.M.)
| | - Gisele Zapata-Sudo
- Programa de Pesquisa em Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil; (J.S.d.S.); (T.L.M.); (B.S.R.); (M.L.C.A.T.); (S.C.P.M.)
- Instituto de Cardiologia Edson Saad, Faculdade de Medicina, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| |
Collapse
|
5
|
Medvedeva MV, Solodilova MA, Bykanova MA, Ivanova NV, Polonikov AV. Polymorphism of the VEGFA Gene and Coronary Artery Disease: Sex Dimorphism in Relationship between the Gene and Disease Predisposition. RUSS J GENET+ 2021. [DOI: 10.1134/s1022795420120108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
6
|
Ma Y, Yao J, Zhou S, Mi Y, Tan X, Zhang C. Enhancing effect of FSH on follicular development through yolk formation and deposition in the low-yield laying chickens. Theriogenology 2020; 157:418-430. [PMID: 32871446 DOI: 10.1016/j.theriogenology.2020.07.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 07/09/2020] [Accepted: 07/09/2020] [Indexed: 01/11/2023]
Abstract
Healthy and efficient development of ovarian follicles largely determines poultry laying performance. In low-yield laying chickens, retarded follicle progression resulted in decreased prehierarchical follicles. In this study the extenuating effect of follicle-stimulating hormone (FSH) on delayed follicular development was investigated in the low-yield chickens. Results showed that FSH administration in vivo accelerated development of prehierarchical follicles, with increased expression of steroidogenic enzymes and follicular angiogenesis through elevating plasma levels of 17β-estradiol, progesterone, luteinizing hormone and the expression of vascular endothelial growth factor and its receptor as well as angiopoietins. Furthermore, treatment with FSH raised expression of lipid uptake and adipogenesis-related proteins and decreased tight junctions between granulosa cells. Meanwhile, the results of the in vivo studies were confirmed by the in vitro studies as FSH promoted development of the cultured prehierarchical follicles with increased angiogenesis, cell proliferation, steroid hormones synthesis and yolk deposition. These results indicated FSH enhanced follicular development in the low-yield laying chickens involving increased follicular angiogenesis.
Collapse
Affiliation(s)
- Yanfen Ma
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Jinwei Yao
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Shuo Zhou
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Yuling Mi
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Xun Tan
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Caiqiao Zhang
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China.
| |
Collapse
|
7
|
Oroxylin A Reduces Vasoconstriction in Rat Aortic Rings through Promoting NO Production and NOS Protein Expression via Estrogen Receptor Signal Pathway. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2020; 2020:9257950. [PMID: 32082399 PMCID: PMC7011478 DOI: 10.1155/2020/9257950] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 09/10/2019] [Accepted: 09/18/2019] [Indexed: 12/25/2022]
Abstract
Oroxylin A, a flavonoid, is naturally produced in many medicinal plants. Our previous study identified it as a phytoestrogen. Based on this, the present study investigated its vasoconstriction reducing effects and whether the action was mediated by the estrogen receptor (ER) signal pathway. Long-term in vitro treatment with oroxylin A reduced Ach-induced vasorelaxation and NE-mediated or KCl-mediated contractile responses in rat aortic rings. These effects were interfered by an ER inhibitor ICI 182,780. Rat cardiac microvascular endothelial cells (CMECs) and aortic vascular smooth muscle cells (VSMCs) were used to study the possible underlying mechanisms. Oroxylin A activated the ER signal pathway. In CMECs, it increased NO production and eNOS protein expression. In VSMCs, it promoted NO production and iNOS protein expression. These effects were also inhibited by ICI 182,780. Besides, oroxylin A stimulated ERα and ERβ protein expression in CMECs and VSMCs. All these findings suggest that the ER signal pathway takes part in the vasoconstriction reducing effects of oroxylin A.
Collapse
|
8
|
Fortini F, Vieceli Dalla Sega F, Caliceti C, Lambertini E, Pannuti A, Peiffer DS, Balla C, Rizzo P. Estrogen-mediated protection against coronary heart disease: The role of the Notch pathway. J Steroid Biochem Mol Biol 2019; 189:87-100. [PMID: 30817989 DOI: 10.1016/j.jsbmb.2019.02.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 02/05/2019] [Accepted: 02/20/2019] [Indexed: 12/28/2022]
Abstract
Estrogen regulates a plethora of biological processes, under physiological and pathological conditions, by affecting key pathways involved in the regulation of cell proliferation, fate, survival and metabolism. The Notch receptors are mediators of communication between adjacent cells and are key determinants of cell fate during development and in postnatal life. Crosstalk between estrogen and the Notch pathway intervenes in many processes underlying the development and maintenance of the cardiovascular system. The identification of molecular mechanisms underlying the interaction between these types of endocrine and juxtacrine signaling are leading to a deeper understanding of physiological conditions regulated by these steroid hormones and, potentially, to novel therapeutic approaches to prevent pathologies linked to reduced levels of estrogen, such as coronary heart disease, and cardiotoxicity caused by hormone therapy for estrogen-receptor-positive breast cancer.
Collapse
Affiliation(s)
| | | | - Cristiana Caliceti
- Department of Chemistry "Giacomo Ciamician", Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | - Elisabetta Lambertini
- Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara, Italy
| | - Antonio Pannuti
- University of Hawaii Cancer Center, University of Hawaii, Honolulu, HI, USA
| | - Daniel S Peiffer
- Oncology Research Institute, Loyola University Chicago: Health Sciences Division, Maywood, Illinois, USA; Department of Microbiology and Immunology, Loyola University Chicago: Health Sciences Division, Maywood, Illinois, USA
| | - Cristina Balla
- Cardiovascular Center, University of Ferrara, Ferrara, Italy
| | - Paola Rizzo
- Maria Cecilia Hospital, GVM Care & Research, Cotignola, RA, Italy; Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy; Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy.
| |
Collapse
|
9
|
Dikici S, Mangır N, Claeyssens F, Yar M, MacNeil S. Exploration of 2-deoxy-D-ribose and 17β-Estradiol as alternatives to exogenous VEGF to promote angiogenesis in tissue-engineered constructs. Regen Med 2019; 14:179-197. [PMID: 30793662 DOI: 10.2217/rme-2018-0068] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Aim: In this study, we explored the angiogenic potential and proangiogenic concentration ranges of 2-deoxy-D-ribose (2dDR) and 17β-Estradiol (E2) in comparison with VEGF. The 2dDR and E2 were then loaded into tissue engineering (TE) scaffolds to investigate their proangiogenic potential when released from fibers. Materials & methods: Ex ovo chick chorioallantoic membrane (CAM) assay was used to evaluate angiogenic activity of 2dDR and E2. Both factors were then introduced into scaffolds via electrospinning to assess their angiogenic potential when released from fibers. Results: Both factors were approximately 80% as potent as VEGF and showed a dose-dependent angiogenic response. The sustained release of both agents from the scaffolds stimulated neovascularization over 7 days in the chorioallantoic membrane assay. Conclusion: We conclude that both 2dDR and E2 provide attractive alternatives to VEGF for the functionalization of tissue engineering scaffolds to promote angiogenesis in vivo.
Collapse
Affiliation(s)
- Serkan Dikici
- Department of Materials Science & Engineering, Kroto Research Institute, University of Sheffield, Sheffield, UK
| | - Naşide Mangır
- Department of Materials Science & Engineering, Kroto Research Institute, University of Sheffield, Sheffield, UK.,Department of Urology, Royal Hallamshire Hospital, Sheffield, United Kingdom
| | - Frederik Claeyssens
- Department of Materials Science & Engineering, Kroto Research Institute, University of Sheffield, Sheffield, UK
| | - Muhammad Yar
- Interdisciplinary Research Center in Biomedical Materials (IRCBM), COMSATS University Islamabad, Lahore, Pakistan
| | - Sheila MacNeil
- Department of Materials Science & Engineering, Kroto Research Institute, University of Sheffield, Sheffield, UK
| |
Collapse
|