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Bundy J, Shaw J, Hammel M, Nguyen J, Robbins C, Mercier I, Suryanarayanan A. Role of β3 subunit of the GABA type A receptor in triple negative breast cancer proliferation, migration, and cell cycle progression. Cell Cycle 2024:1-18. [PMID: 38623967 DOI: 10.1080/15384101.2024.2340912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 02/29/2024] [Indexed: 04/17/2024] Open
Abstract
Triple negative breast cancer (TNBC) is known for its heterogeneous nature and aggressive onset. The unresponsiveness to hormone therapies and immunotherapy and the toxicity of chemotherapeutics account for the limited treatment options for TNBC. Ion channels have emerged as possible therapeutic candidates for cancer therapy, but little is known about how ligand gated ion channels, specifically, GABA type A ligand-gated ion channel receptors (GABAAR), affect cancer pathogenesis. Our results show that the GABAA β3 subunit is expressed at higher levels in TNBC cell lines than non-tumorigenic cells, therefore contributing to the idea that limiting the GABAAR via knockdown of the GABAA β3 subunit is a potential strategy for decreasing the proliferation and migration of TNBC cells. We employed pharmacological and genetic approaches to investigate the role of the GABAA β3 subunit in TNBC proliferation, migration, and cell cycle progression. The results suggest that pharmacological antagonism or genetic knockdown of GABAA β3 subunit decreases TNBC proliferation and migration. In addition, GABAA β3 subunit knockdown causes cell cycle arrest in TNBC cell lines via decreased cyclin D1 and increased p21 expression. Our findings suggest that membrane bound GABAA receptors containing the β3 subunit can be further developed as a potential novel target for the treatment of TNBC.
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Affiliation(s)
- J Bundy
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, Saint Joseph's University, Pharmacology and Toxicology Center (PTC), Philadelphia, PA, USA
| | - J Shaw
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, Saint Joseph's University, Pharmacology and Toxicology Center (PTC), Philadelphia, PA, USA
| | - M Hammel
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, Saint Joseph's University, Pharmacology and Toxicology Center (PTC), Philadelphia, PA, USA
| | - J Nguyen
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, Saint Joseph's University, Pharmacology and Toxicology Center (PTC), Philadelphia, PA, USA
| | - C Robbins
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, Saint Joseph's University, Pharmacology and Toxicology Center (PTC), Philadelphia, PA, USA
| | | | - A Suryanarayanan
- Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, Saint Joseph's University, Pharmacology and Toxicology Center (PTC), Philadelphia, PA, USA
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Nelson YM, Bundy J, Harmon E, Hammond L, Robinson K, Lyons N, Vessels R, Bush K, Thomas-Payne D. Factors affecting the advancement of Black nurses into leadership roles: A scoping review. Nurs Outlook 2023; 71:102000. [PMID: 37467652 DOI: 10.1016/j.outlook.2023.102000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Revised: 05/29/2023] [Accepted: 06/11/2023] [Indexed: 07/21/2023]
Abstract
BACKGROUND The profession of nursing has recognized the lack of diversity in nursing leadership. Nurses of color represent fewer than 20% of leadership roles in nursing administration, education, and professional organizations. Efforts are needed to identify and implement strategies to increase the representation of nurses of color in positions of high influence. PURPOSE To review the literature to uncover the factors that may impact Black nurses in their pursuit of leadership roles in nursing administration, education, and professional organizations. METHODS The authors conducted a scoping review, searching CINAHL and PubMed databases in November 2022 for peer-reviewed English-language studies of leadership among U.S. nurses. They excluded studies that did not include a research method, did not have participants, a minimum of baccalaureate preparation as an inclusion criterion for participants, or were published before January 1, 2012. DISCUSSION Of 331 articles identified, a total of 12 met the inclusion criteria. Evaluation of the studies revealed three concepts related to mentorship, racism, and hiring practices. Of the 12 studies, 9 addressed issues related to mentorship, 5 addressed issues related to racism, and 2 addressed issues related to hiring practices. Some studies address more than one of the concepts. Ten were qualitative studies, and two were quantitative studies. CONCLUSION Findings suggest that Black nurse leaders are faced with obstacles and challenges when considering entering and/or staying in leadership roles. The limited amount of research on Black nurses in leadership roles remains inadequate.
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Affiliation(s)
- Yolanda M Nelson
- School of Nursing and Health Sciences, The College of New Jersey, Ewing, NJ.
| | | | - Elissa Harmon
- Department of Healthcare, Thomas Jefferson University Hospital, Philadelphia, PA
| | - Lisa Hammond
- Department of Healthcare, Einstein Medical Center, Philadelphia, PA
| | - Karima Robinson
- Department of Healthcare, Cooper University Hospital, Camden, NJ
| | - Nyree Lyons
- Department of Healthcare, The Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Renée Vessels
- Department of Healthcare, Temple University Hospital, Philadelphia, PA
| | - Kimberly Bush
- Department of Healthcare, Thomas Jefferson University Hospital, Philadelphia, PA
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Bundy J. Effective strategies to improve the college-going process of Black students considering nursing education: A Case Study Approach. Nurse Educ Today 2022; 118:105522. [PMID: 36081268 DOI: 10.1016/j.nedt.2022.105522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 07/17/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
OBJECTIVES The objective of the study was to describe the mentoring relationship and parental involvement during the college-going process of nursing education from the student's perspective. DESIGN Qualitative research design was employed utilizing Yin's case study methodology. SETTINGS The mentoring program took place over a 6-month period in a large urban city located in the United States. PARTICIPANTS A total of six high school students and 6 nurses participated in the study resulting in 6 mentor dyads. METHODS Data was collected using multiple sources of evidence including the Mentoring Match Demographic Questionnaire (MMDQ), Parental Involvement Scale (PIS), electronic documentation, and interviews. Information from the MMDQ was completed prior to the start of the mentoring program and used to assign mentor dyads. All other sources of evidence were administered and analyzed at the end of the mentoring program. RESULTS Six themes emerged capturing the students' perspective of mentoring and parental involvement during the college-going process of nursing education. The themes were (a) Beneficial Relationship, (b) Adaptive Communication, (c) Strengths and Limitations, (d) Good Mentor Characteristics and Qualities, (e) Goal Setting and (f) Parent Involvement: "Being there emotionally". Parental involvement was moderate for most student mentees participating in the mentoring program. CONCLUSION Developing mentoring relationships with professional nurses and increasing parental involvement is an effective strategy to improve the college-going process of nursing education of first-generation Black high school students.
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Affiliation(s)
- Jawanza Bundy
- Widener University, One University Place, Chester, PA 19103, United States of America.
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Bundy J, Hage A, Jiao A, Wadhwa V, Gutta N, Srinivasa R, Gemmete J, Chick J. Abstract No. 577 Limited clinical utility of chest radiography in asymptomatic patients after interventional radiology-performed ultrasound-guided thoracentesis: analysis of 3022 consecutive patients. J Vasc Interv Radiol 2020. [DOI: 10.1016/j.jvir.2019.12.638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Jiao A, Wadhwa V, Bundy J, Hage A, Srinivasa R, Gemmete J, Lee E, Chick J. Abstract No. 462 Scholarly activities and indices among academic endovascular specialists: a comparative analysis between interventional radiologists and vascular surgeons. J Vasc Interv Radiol 2020. [DOI: 10.1016/j.jvir.2019.12.523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Kutsenko O, Liu R, Borror W, Heiberger C, Wazen J, Bundy J, Koroma M, Holly B, Buckalew J, Huang J. 4:03 PM Abstract No. 124 Stop the bleeding: What interventional radiologists need to know about the Medicare physician fee schedule cut. J Vasc Interv Radiol 2020. [DOI: 10.1016/j.jvir.2019.12.155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Bundy J, Hage A, Srinivasa R, Gemmete J, Srinivasa R, Jairath N, Anand R, Dasika N, Chauhan N, Chick J. 03:09 PM Abstract No. 249 Intra-arterial ampicillin and gentamicin and the incidence of splenic abscesses following splenic artery embolization: a 20-year case control study in 213 patients. J Vasc Interv Radiol 2019. [DOI: 10.1016/j.jvir.2018.12.310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Siberski C, Bundy J. 8 Identifying factors that affect the transition of transfer students to a four-year university through the use of focus groups. J Anim Sci 2018. [DOI: 10.1093/jas/sky404.1092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- C Siberski
- Iowa State University,Ames, IA, United States
| | - J Bundy
- Iowa State University,Ames, IA, United States
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Bundy J. 467 Organization of a First-Semester Learning Community Based on Student Interests and Backgrounds in Coordination with an Introductory Animal Science Orientation Course. J Anim Sci 2018. [DOI: 10.1093/jas/sky073.464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- J Bundy
- Iowa State University, Ames, IA
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Bundy J, Srinivasa R, Gemmete J, Hage A, Majdalany B, Khaja M, Saad W, Chick J. Abstract No. 589 Vascular and lymphatic complications following thoracic duct cannulation: experience in 58 patients. J Vasc Interv Radiol 2018. [DOI: 10.1016/j.jvir.2018.01.634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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Bundy J, Srinivasa R, Gemmete J, Hage A, Majdalany B, Saad W, Chick J. 4:03 PM Abstract No. 168 Results of percutaneous cholecystostomy tube placement in 324 patients. J Vasc Interv Radiol 2018. [DOI: 10.1016/j.jvir.2018.01.190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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Wierre N, Williams H, Davies J, Bundy J. 95 Phenotyping cystic fibrosis clinical isolates of Pseudomonas aeruginosa reveals greater between-patient than within-patient diversity. J Cyst Fibros 2017. [DOI: 10.1016/s1569-1993(17)30459-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
In five healthy subjects and 18 patients, cine magnetic resonance (MR) imaging of the heart was performed with a true fast imaging with steady-state precession (FISP) sequence. Results were compared both quantitatively and qualitatively with those at cine fast low-angle shot (FLASH) MR imaging. The blood-myocardial contrast-to-noise ratio (CNR) was 2.0 times higher and the normalized (for measurement time and pixel size) blood-myocardial CNR was 4.0 times higher for true FISP compared with FLASH MR imaging. Qualitative scores for image quality were significantly higher with true FISP MR imaging. Segmented cine true FISP MR imaging generated high-contrast MR images of the heart in healthy subjects and in patients with heart disease and produced image quality superior to that with cine FLASH MR imaging.
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Affiliation(s)
- J C Carr
- Department of Radiology, Northwestern University Medical School, 448 E Ontario St, Suite 700, Chicago, IL 60611, USA.
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Conway SJ, Bundy J, Chen J, Dickman E, Rogers R, Will BM. Decreased neural crest stem cell expansion is responsible for the conotruncal heart defects within the splotch (Sp(2H))/Pax3 mouse mutant. Cardiovasc Res 2000; 47:314-28. [PMID: 10946068 DOI: 10.1016/s0008-6363(00)00098-5] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
OBJECTIVE Several mouse models of cardiac neural crest cell (NCC)-associated conotruncal heart defects exist, but the specific cellular and molecular defects within cardiac NCC morphogenesis remain largely unknown. Our objective was to investigate the underlying mechanisms resulting in outflow tract defects and why insufficient cardiac NCC reach the heart of the Splotch (Sp(2H)) mouse mutant embryo. METHODS For this study we used in vitro cell culture techniques, in vivo mouse-chick chimeras, BrdU cell proliferation labeling, TUNEL labeling to visualize apoptosis and the molecular markers AP-2, Wnt-1 and Wnt-3a to characterize NCC morphogenesis in vivo. RESULTS Expression of the NCC marker AP-2 revealed an extensive reduction in migratory NCC, however the rates of cell proliferation and apoptosis were unaffected, and do not account for the Sp(2H) NCC-associated heart defects. Further expression analysis revealed that Wnt-1, but not Wnt-3a, is expressed at decreased levels within Sp(2H) and that the cardiac NCC fail to undergo normal NC stem cell proliferative expansion prior to migration while still in the neural folds. However, when placed into a wild-type matrix or a tissue culture environment, the Sp(2H) cardiac NCC could migrate normally. Additionally, this reduced population of Sp(2H) NC stem cells do migrate properly within the Sp(2H) environment, as observed by neurofilament expression and cardiac innervation. CONCLUSIONS Taken together, all these data indicate that the Sp(2H) defect is intrinsic to the NC stem cells themselves and that there is a decrease in the number of pre-migratory cardiac NCC that form. It appears that this decrease in NCC number is the primary defect that ultimately leads to a lack of a cardiac NCC-derived Sp(2H) outflow tract septum.
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Affiliation(s)
- S J Conway
- Institute of Molecular Medicine and Genetics and Department of Cell Biology and Anatomy, Medical College of Georgia, Augusta 30912-2640, USA.
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Abstract
Although chondroitin sulfate proteoglycans (CSPGs) are major components of the embryonic extracellular matrix, little attention has been paid to specific CSPGs in early heart development, in part because appropriate antibodies were not available. Therefore we prepared specific polyclonal antibodies against chicken aggrecan, versican, neurocan, and phosphacan. Western blotting and immunohistochemical studies revealed the presence of aggrecan and versican in stages 12-21 chicken embryo hearts in distinctive spatial and temporal patterns. Because this is the first demonstration of aggrecan in heart tissue, we further used RT-PCR to confirm that aggrecan is expressed in the heart and in situ hybridization to confirm the pattern of expression determined using antibodies. Versican is found in the myocardium and the myocardial basement membrane. In contrast, aggrecan is specifically colocalized with several groups of migrating cells including endocardial cushion tissue cells, epicardial cells, a mesenchymal cell population in the outflow tract that may be of neural crest origin, and a mesenchymal cell population in the inflow tract. The combined observations indicate that versican and aggrecan are expressed in unique patterns and suggest that they play very different roles in development.
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Affiliation(s)
- M K Zanin
- Division of Rheumatology, The Medical University of South Carolina, Charleston, South Carolina 29425, USA
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Kim RJ, Fieno DS, Parrish TB, Harris K, Chen EL, Simonetti O, Bundy J, Finn JP, Klocke FJ, Judd RM. Relationship of MRI delayed contrast enhancement to irreversible injury, infarct age, and contractile function. Circulation 1999; 100:1992-2002. [PMID: 10556226 DOI: 10.1161/01.cir.100.19.1992] [Citation(s) in RCA: 1694] [Impact Index Per Article: 67.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Contrast MRI enhancement patterns in several pathophysiologies resulting from ischemic myocardial injury are controversial or have not been investigated. We compared contrast enhancement in acute infarction (AI), after severe but reversible ischemic injury (RII), and in chronic infarction. METHODS AND RESULTS In dogs, a large coronary artery was occluded to study AI and/or chronic infarction (n = 18), and a second coronary artery was chronically instrumented with a reversible hydraulic occluder and Doppler flowmeter to study RII (n = 8). At 3 days after surgery, cine MRI revealed reduced wall thickening in AI (5+/-6% versus 33+/-6% in normal, P<0.001). In RII, wall thickening before, during, and after inflation of the occluder for 15 minutes was 35+/-5%, 1+/-8%, and 21+/-10% and Doppler flow was 19.8+/-5.3, 0.2+/-0.5, and 56.3+/-17.7 (peak hyperemia) cm/s, respectively, confirming occlusion, transient ischemia, and reperfusion. Gd-DTPA-enhanced MR images acquired 30 minutes after contrast revealed hyperenhancement of AI (294+/-96% of normal, P<0.001) but not of RII (98+/-6% of normal, P = NS). Eight weeks later, the chronically infarcted region again hyperenhanced (253+/-54% of normal, n = 8, P<0.001). High-resolution (0.5 x 0.5 x 0.5 mm) ex vivo MRI demonstrated that the spatial extent of hyperenhancement was the same as the spatial extent of myocyte necrosis with and without reperfusion at 1 day (R = 0.99, P<0.001) and 3 days (R = 0.99, P<0.001) and collagenous scar at 8 weeks (R = 0.97, P<0.001). CONCLUSIONS In the pathophysiologies investigated, contrast MRI distinguishes between reversible and irreversible ischemic injury independent of wall motion and infarct age.
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Affiliation(s)
- R J Kim
- Northwestern University Medical School, Feinberg Cardiovascular Research Institute, Department of Medicine, Chicago, IL 60611-3008, USA
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Abstract
Although the sodium-calcium exchanger (NCX1) is encoded by a single gene, it is widely expressed in both fetal and adult tissues and functions in many diverse physiological processes to maintain intracellular calcium homeostasis. In order to determine whether NCX1 is also ubiquitously expressed in the early mouse embryo, in situ hybridization and RT-PCR were used to determine the spacio-temporal expression of NCX1. Our results indicate that NCX1 expression is present within the 7.75-8.0 dpc cardiogenic plate before the first heartbeat, and that NCX1 is initially expressed in a heart-restricted pattern within the early mouse embryo. However, in more developed embryos (11.0 dpc and older) NCX1 is expressed in other tissues.
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Affiliation(s)
- S V Koushik
- Institute of Molecular Medicine and Genetics and Department of Cell Biology and Anatomy, Medical College of Georgia, Augusta 30912, USA
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Winnier GE, Kume T, Deng K, Rogers R, Bundy J, Raines C, Walter MA, Hogan BL, Conway SJ. Roles for the winged helix transcription factors MF1 and MFH1 in cardiovascular development revealed by nonallelic noncomplementation of null alleles. Dev Biol 1999; 213:418-31. [PMID: 10479458 DOI: 10.1006/dbio.1999.9382] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The murine Mf1 and Mfh1 genes have overlapping patterns of expression in the embryo and encode forkhead/winged helix transcription factors with virtually identical DNA binding domains. Previous studies have shown that Mfh1 null mutants have severe cardiovascular defects, including interruptions and coarctations of the aortic arch and ventricular septal defects (Iida et al., Development 124, 4627-4638, 1997). Here, we show that Mf1(lacZ) homozygous null mutants also have a similar spectrum of cardiovascular abnormalities. Moreover, most embryos doubly heterozygous for Mfh1(tm1) and Mf1(lacZ) die before birth with interruptions and coarctations of the aortic arch, dysgenesis of the aortic and pulmonary valves, ventricular septal defects, and other cardiac anomalies. This nonallelic noncomplementation and the similar patterns of expression of the two genes in the mesenchyme and endothelial cells of the branchial arches, outflow tract, and heart suggest that Mf1 and Mfh1 play interactive roles in the morphogenesis of the cardiovascular system. Implications for the development of human congenital heart defects are discussed.
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Affiliation(s)
- G E Winnier
- Howard Hughes Medical Institute, Vanderbilt University Medical Center, Nashville, Tennessee, 37232-2175, USA
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Clark TG, Conway SJ, Scott IC, Labosky PA, Winnier G, Bundy J, Hogan BL, Greenspan DS. The mammalian Tolloid-like 1 gene, Tll1, is necessary for normal septation and positioning of the heart. Development 1999; 126:2631-42. [PMID: 10331975 DOI: 10.1242/dev.126.12.2631] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mammalian Tolloid-like 1 (mTLL-1) is an astacin-like metalloprotease, highly similar in domain structure to the morphogenetically important proteases bone morphogenetic protein-1 (BMP-1) and Drosophila Tolloid. To investigate possible roles for mTLL-1 in mammalian development, we have used gene targeting in ES cells to produce mice with a disrupted allele for the corresponding gene, Tll1. Homozygous mutants were embryonic lethal, with death at mid-gestation from cardiac failure and a unique constellation of developmental defects that were apparently confined solely to the heart. Constant features were incomplete formation of the muscular interventricular septum and an abnormal and novel positioning of the heart and aorta. Consistent with roles in cardiac development, Tll1 expression was specific to precardiac tissue and endocardium in 7.5 and 8.5 days p.c. embryos, respectively. Tll1 expression was also high in the developing interventricular septum, where expression of the BMP-1 gene, Bmp1, was not observed. Cardiac structures that were not affected in Tll1−/− embryos either showed no Tll1 expression (atrio-ventricular cushions) or showed overlapping expression of Tll1 and Bmp1 (aortico-pulmonary septum), suggesting that products of the Bmp1 gene may be capable of functionally substituting for mTLL-1 at sites in which they are co-expressed. Together, the various data show that mTLL-1 plays multiple roles in formation of the mammalian heart and is essential for formation of the interventricular septum.
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Affiliation(s)
- T G Clark
- Department of Pathology and Laboratory Medicine and Cardiovascular Research Center, University of Wisconsin, Madison, WI 53706, USA
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Abstract
Immobilized lectins have now been incorporated into affinity surfaces that can be used to isolate broad classes of samples for mass spectrometric analysis. A carbohydrate and a bacterial species that displays the carbohydrate binding motif were isolated and concentrated out of solutions containing salt, urea, buffers, and other contaminants that are deleterious to MALDI mass spectrometry. Concanavalin A was immobilized to a gold foil via a self-assembled monolayer. Samples in phosphate buffer or urine were applied to the capture surface and allowed to interact. The capture surface was then washed to remove salts and other unbound components and subjected to matrix-assisted laser desorption/ionization on a time-of-flight mass spectrometer. The lectin-derivatized surface allowed samples to be concentrated and readily characterized at relatively low levels.
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Affiliation(s)
- J Bundy
- Department of Chemistry and Biochemistry, University of Maryland, College Park College Park 20742, USA
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Bundy J, Rogers R, Hoffman S, Conway SJ. Segmental expression of aggrecan in the non-segmented perinotochordal sheath underlies normal segmentation of the vertebral column. Mech Dev 1998; 79:213-7. [PMID: 10349634 DOI: 10.1016/s0925-4773(98)00179-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The embryonic vertebral column is derived from the unsegmented axial mesenchyme surrounding the notochord, and its development and differentiation are influenced by the notochord. The role of cartilage in determining the ultimate pattern of the segmental skeleton has been well documented, but a gene whose segmental expression corresponds to the pattern of the developing skeleton has yet to be identified. We show that chick aggrecan is initially expressed within the entire length of the notochord, and as development proceeds, aggrecan expression becomes restricted to the surrounding perinotochordal sheath in a segmental pattern, mirroring the differentiated somite pattern.
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Affiliation(s)
- J Bundy
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta 30912, USA
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