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Cordoza M, Dinges D, Asch D, Shea J, Bellini L, Malone S, Desai S, Volpp K, Mott C, Coats S, Mollicone D, Basner M. Changes in Alertness Over Consecutive Workdays for Internal Medicine Interns: A Secondary Analysis of the iCOMPARE Trial. Sleep Med 2022. [DOI: 10.1016/j.sleep.2022.05.090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Robbins-Welty GA, Coats S, Tuck AN, Lao BK, Lane Z. Pulmonary Embolism during a Retrial of Low-dose Clozapine. Clin Psychopharmacol Neurosci 2022; 20:578-580. [PMID: 35879043 PMCID: PMC9329109 DOI: 10.9758/cpn.2022.20.3.578] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 11/29/2021] [Indexed: 01/10/2023]
Abstract
Pulmonary emboli (PE) are increasingly recognized as an adverse effect of clozapine. However, little is known about the characteristics or mechanisms of clozapine-associated PE. We present a case of a 34-year-old with treatment-refractory schizophrenia who developed rhabdomyolysis during his first clozapine trial. During re-trial on a lower dose than his initial trial, the patient developed chest pain that he attributed to “pacemakers.” The pleuritic description and associated tachycardia prompted medical workup and the patient was ultimately diagnosed with a clozapine-associated PE. The patient’s only risk factors for PE were obesity and tobacco use, while his hypercoagulability workup was unrevealing. Clozapine use was continued at a lower dose following these adverse effects given inefficacy of other agents in managing the patient’s psychotic symptoms. The patient experienced significant relief of psychotic symptoms with continued clozapine therapy and a course of electroconvulsive therapy. The patient’s presentation was unusual in that it occurred during a retrial of clozapine, after the initial trial was stopped when he developed rhabdomyolysis. This case demonstrates the importance of maintaining vigilance for PE in patients on clozapine as well as not dismissing somatic complaints in patients experiencing psychosis. Additionally, given his history rhabdomyolysis, an uncommon adverse effect of clozapine, the development of a second uncommon adverse effect (PE) raises the question of whether these events may be associated.
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Affiliation(s)
- Gregg Alan Robbins-Welty
- Department of Psychiatry and Behavioral Sciences, NC, USA
- Department of Medicine, Duke University Medical Center, NC, USA
| | - Shannon Coats
- School of Medicine, Duke University School of Medicine, Durham, NC, USA
| | - Andrew N. Tuck
- Department of Psychiatry and Behavioral Sciences, NC, USA
| | - Bryan K. Lao
- Department of Psychiatry and Behavioral Sciences, NC, USA
| | - Zachary Lane
- Department of Psychiatry and Behavioral Sciences, NC, USA
- Central Regional Hospital, Division of State-Operated Healthcare Facilities, Butner, NC, USA
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Jacox LA, Tang N, Li Y, Bocklage C, Graves C, Coats S, Miao M, Glesener T, Kwon J, Giduz N, Lin FC, Martinez J, Ko CC. Orthodontic loading activates cell-specific autophagy in a force-dependent manner. Am J Orthod Dentofacial Orthop 2022; 161:423-436.e1. [PMID: 35039202 DOI: 10.1016/j.ajodo.2020.09.034] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/01/2020] [Accepted: 09/01/2020] [Indexed: 01/07/2023]
Abstract
INTRODUCTION Orthodontic tooth movement (OTM) relies on bone remodeling and controlled aseptic inflammation. Autophagy, a conserved homeostatic pathway, has been shown to play a role in bone turnover. We hypothesize that autophagy participates in regulating bone remodeling during OTM in a force-dependent and cell type-specific manner. METHODS A split-mouth design was used to load molars with 1 of 3 force levels (15, 30, or 45 g of force) in mice carrying a green fluorescent protein-LC3 transgene to detect cellular autophagy. Fluorescent microscopy and quantitative polymerase chain reaction analyses were used to evaluate autophagy activation and its correlation with force level. Cell type-specific antibodies were used to identify cells with green fluorescent protein-positive puncta (autophagosomes) in periodontal tissues. RESULTS Autophagic activity increased shortly after loading with moderate force and was associated with the expression of bone turnover, inflammatory, and autophagy markers. Different load levels resulted in altered degrees of autophagic activation, gene expression, and osteoclast recruitment. Autophagy was specifically induced by loading in macrophages and osteoclasts found in the periodontal ligament and alveolar bone. Data suggest autophagy participates in regulating bone turnover during OTM. CONCLUSIONS Autophagy is induced in macrophage lineage cells by orthodontic loading in a force-dependent manner and plays a role during OTM, possibly through modulation of osteoclast bone resorption. Exploring the roles of autophagy in OTM is medically relevant, given that autophagy is associated with oral and systemic inflammatory conditions.
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Affiliation(s)
- Laura Anne Jacox
- Division of Craniofacial and Surgical Care, and Division of Oral and Craniofacial Health Sciences, Adams School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Na Tang
- Division of Oral and Craniofacial Health Sciences, Adams School of Dentistry, University of North Carolina, Chapel Hill, NC Department of Oral Medicine, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Yina Li
- Division of Craniofacial and Surgical Care, Adams School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Clare Bocklage
- Division of Craniofacial and Surgical Care, and Division of Oral and Craniofacial Health Sciences, Adams School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Christina Graves
- Division of Oral and Craniofacial Health Sciences, Adams School of Dentistry, University of North Carolina, Chapel Hill, NC
| | | | - Michael Miao
- Curriculum in Oral and Craniofacial Biomedicine, Adams School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Tim Glesener
- Division of Oral and Craniofacial Health Sciences, Adams School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Jane Kwon
- Division of Craniofacial and Surgical Care, and Division of Oral and Craniofacial Health Sciences, Adams School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Natalie Giduz
- Division of Craniofacial and Surgical Care, Adams School of Dentistry, University of North Carolina, Chapel Hill, NC
| | - Feng-Chang Lin
- Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC
| | - Jennifer Martinez
- National Institutes of Health, Bethesda, Md National Institute of Environmental Health Sciences, Research Triangle Park, Durham, NC
| | - Ching-Chang Ko
- Division of Orthodontics, College of Dentistry, The Ohio State University, Columbus, Ohio.
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Li Y, Jacox LA, Coats S, Kwon J, Xue P, Tang N, Rui Z, Wang X, Kim YI, Wu TJ, Lee YT, Wong SW, Chien CH, Cheng CW, Gross R, Lin FC, Tseng H, Martinez J, Ko CC. Roles of autophagy in orthodontic tooth movement. Am J Orthod Dentofacial Orthop 2021; 159:582-593. [PMID: 33771430 PMCID: PMC10911631 DOI: 10.1016/j.ajodo.2020.01.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [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] [Received: 04/01/2019] [Revised: 01/01/2020] [Accepted: 01/01/2020] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Orthodontic tooth movement (OTM) relies on efficient remodeling of alveolar bone. While a well-controlled inflammatory response is essential during OTM, the mechanism regulating inflammation is unknown. Autophagy, a conserved catabolic pathway, has been shown to protect cells from excess inflammation in disease states. We hypothesize that autophagy plays a role in regulating inflammation during OTM. METHODS A split-mouth design was used to force load molars in adult male mice, carrying a GFP-LC3 transgene for in vivo detection of autophagy. Confocal microscopy, Western blot, and quantitative polymerase chain reaction analyses were used to evaluate autophagy activation in tissues of loaded and control molars at time points after force application. Rapamycin, a Food and Drug Administration-approved immunosuppressant, was injected to evaluate induction of autophagy. RESULTS Autophagy activity increases shortly after loading, primarily on the compression side of the tooth, and is closely associated with inflammatory cytokine expression and osteoclast recruitment. Daily administration of rapamycin, an autophagy activator, led to reduced tooth movement and osteoclast recruitment, suggesting that autophagy downregulates the inflammatory response and bone turnover during OTM. CONCLUSIONS This is the first demonstration that shows that autophagy is induced by orthodontic loading and plays a role during OTM, likely via negative regulation of inflammatory response and bone turnover. Exploring roles of autophagy in OTM holds great promise, as aberrant autophagy is associated with periodontal disease and its related systemic inflammatory disorders.
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Affiliation(s)
- Yina Li
- Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, Nc
| | - Laura Anne Jacox
- Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, Nc
| | - Shannon Coats
- Duke University Medical Center Greenspace, Durham, Nc
| | - Jane Kwon
- Oral and Craniofacial Health Sciences, School of Dentistry, University of North Carolina, Chapel Hill, Nc
| | - Peng Xue
- Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, Nc
| | - Na Tang
- Oral and Craniofacial Health Sciences, School of Dentistry, University of North Carolina, Chapel Hill, Nc Department of Oral Medicine, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, Sichuan, China
| | - Zou Rui
- Oral and Craniofacial Health Sciences, School of Dentistry, University of North Carolina, Chapel Hill, Nc Department of Orthodontics, Stomatological Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Xiaoyu Wang
- Oral and Craniofacial Health Sciences, School of Dentistry, University of North Carolina, Chapel Hill, Nc Department of Dentistry, Beijing Tiantan Hospital, Capital Medical University, Beijing, Beijing, China
| | - Yong-Il Kim
- Oral and Craniofacial Health Sciences, School of Dentistry, University of North Carolina, Chapel Hill, Nc Department of Orthodontics, School of Dentistry, Pusan National University, Yangsan, South Korea
| | - Te Ju Wu
- Oral and Craniofacial Health Sciences, School of Dentistry, University of North Carolina, Chapel Hill, Nc Department of Orthodontics, Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Yan-Ting Lee
- Oral and Craniofacial Health Sciences, School of Dentistry, University of North Carolina, Chapel Hill, Nc
| | - Sing Wai Wong
- Department of Periodontology, School of Dentistry, University of North Carolina, Chapel Hill, Nc
| | - Chia Hui Chien
- Oral and Craniofacial Health Sciences, School of Dentistry, University of North Carolina, Chapel Hill, Nc Division of Prosthodontics, Department of Dentistry, Tainan, Taiwan
| | - Chih-Wen Cheng
- Oral and Craniofacial Health Sciences, School of Dentistry, University of North Carolina, Chapel Hill, Nc Division of Prosthodontics, Department of Dentistry, Tainan, Taiwan
| | - Ryan Gross
- Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, Nc
| | - Feng-Chang Lin
- Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, Nc
| | - Henry Tseng
- Duke University Medical Center Greenspace and Glaucoma Division, Duke Eye Center, Durham, Nc
| | - Jennifer Martinez
- National Institutes of Health, Bethesda, Ma National Institute of Environmental Health Sciences, Research Triangle Park, Durham, Nc
| | - Ching-Chang Ko
- Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, Nc.
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Cecchi F, Carrolle D, Gustavson M, Sridhar S, de los Reyes M, Thyparambil S, Bhalkikar A, Liao WL, Coats S, Hembrough T. 13P HER2 low testing in breast cancer: How to optimize detection. Ann Oncol 2020. [DOI: 10.1016/j.annonc.2020.03.149] [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: 11/26/2022] Open
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Coats S, Smerdon JE, Cook BI, Seager R, Cook ER, Anchukaitis KJ. Internal ocean-atmosphere variability drives megadroughts in Western North America. Geophys Res Lett 2016; 43:9886-9894. [PMID: 29780186 PMCID: PMC5956231 DOI: 10.1002/2016gl070105] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Multidecadal droughts that occurred during the Medieval Climate Anomaly represent an important target for validating the ability of climate models to adequately characterize drought risk over the near-term future. A prominent hypothesis is that these megadroughts were driven by a centuries-long radiatively forced shift in the mean state of the tropical Pacific Ocean. Here we use a novel combination of spatiotemporal tree-ring reconstructions of Northern Hemisphere hydroclimate to infer the atmosphere-ocean dynamics that coincide with megadroughts over the American West, and find that these features are consistently associated with ten-to-thirty year periods of frequent cold El Niño Southern Oscillation conditions and not a centuries-long shift in the mean of the tropical Pacific Ocean. These results suggest an important role for internal variability in driving past megadroughts. State-of-the art climate models from the Coupled Model Intercomparison Project phase 5, however, do not simulate a consistent association between megadroughts and internal variability of the tropical Pacific Ocean, with implications for our confidence in megadrought risk projections.
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Affiliation(s)
- S. Coats
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado
| | - J. E. Smerdon
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York
| | - B. I. Cook
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York
- NASA Goddard Institute for Space Studies, New York, New York
| | - R. Seager
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York
| | - E. R. Cook
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York
| | - K. J. Anchukaitis
- Department of Geography and Development and Laboratory of Tree Ring Research, University of Arizona, Tucson, Arizona
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Steiner P, Wetzel L, Camara M, Schifferli K, Baffa R, LaVallee T, Coats S, Jallal B, Trail P, Chang Y. 57 Glioblastoma multiforme is characterized by high incidence of PDGFRalpha expression and susceptibility to the PDGFRalphaspecific antibody MEDI-575 in mouse tumor models. EJC Suppl 2010. [DOI: 10.1016/s1359-6349(10)71762-6] [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: 10/18/2022] Open
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Steiner P, Wetzel L, Schifferli K, Camara M, Baffa R, LaVallee T, Jallal B, Coats S, Trail P, Chang Y. 100 Inhibition of PDGFRalpha in tumor stroma with MEDI-575 enhances activity of carboplatin/paclitaxel and delays tumor regrowth in a NSCLC xenograft model. EJC Suppl 2010. [DOI: 10.1016/s1359-6349(10)71805-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Abstract
ADAM15 is a member of the family of metalloprotease-disintegrins that have been shown to interact with integrins in an RGD- and non-RGD-dependent manner. In the present study, we examined the effects of ADAM15 overexpression on cell-matrix and cell-cell interactions in NIH3T3 cells. Tetracycline-regulated ADAM15 overexpression in NIH3T3 cells leads to an inhibition of migration on a fibronectin-coated filter in a Boyden chamber assay and in a scratch wound model. The effects of ADAM15 overexpression on cell migration are not due to changes in matrix attachment or to the lack of extracellular signal-regulated kinase signaling response to PDGF or fibronectin. However, a decrease in monolayer permeability with ADAM15 overexpression and altered cell morphology suggest a possible increase in cell-cell interaction. Analysis of adhesion of NIH3T3 cells to a polyclonal population of cells retrovirally transduced to overexpress ADAM15 demonstrates a 45% increase in cell adhesion, compared with enhanced green fluorescent protein-expressing control cells. In addition, we demonstrate localization of HA-epitope-tagged ADAM15 to cell-cell contacts in an epithelial cell line that forms extensive cell-cell contact structures. Thus, overexpression of ADAM15 in NIH3T3 cells appears to enhance cell-cell interactions, as suggested by decreased cell migration, altered cell morphology at the wound edge, decreased monolayer permeability, and increased cell adhesion to monolayers of cells expressing ADAM15 by retroviral transduction.
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Affiliation(s)
- B Herren
- Department of Pathology, University of Washington School of Medicine, Seattle, Washington 98104-2499, USA
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Mason DP, Kenagy RD, Hasenstab D, Bowen-Pope DF, Seifert RA, Coats S, Hawkins SM, Clowes AW. Matrix metalloproteinase-9 overexpression enhances vascular smooth muscle cell migration and alters remodeling in the injured rat carotid artery. Circ Res 1999; 85:1179-85. [PMID: 10590245 DOI: 10.1161/01.res.85.12.1179] [Citation(s) in RCA: 192] [Impact Index Per Article: 7.7] [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: 11/16/2022]
Abstract
Matrix metalloproteinase-9 (MMP-9) has been implicated in the pathogenesis of atherosclerosis as well as intimal hyperplasia after vascular injury. We used Fischer rat smooth muscle cells (SMCs) overexpressing MMP-9 to determine the role of MMP-9 in migration and proliferation as well as in vessel remodeling after balloon denudation. Fischer rat SMCs were stably transfected with a cDNA for rat MMP-9 under the control of a tetracycline-regulatable promoter. In this system, MMP-9 was overexpressed in the absence, but not in the presence, of tetracycline. In vitro SMC migration was determined using a collagen invasion assay as well as a Boyden chamber assay. In vivo migration was determined by measuring the invasion into the medial and intimal layers of transduced SMCs seeded on the outside of the artery. Transduced SMCs were also seeded on the luminal surface, and the effect of local MMP-9 overexpression on vascular structure was measured morphometrically at intervals up to 28 days. MMP-9 overexpression enhanced SMC migration in both the collagen invasion assay and Boyden chamber in vitro, increased SMC migration into an arterial matrix in vivo, and altered vessel remodeling by increasing the vessel circumference, thinning the vessel wall and decreasing intimal matrix content. These results demonstrate that MMP-9 enhances vascular SMC migration in vitro and in vivo and alters postinjury vascular remodeling.
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Affiliation(s)
- D P Mason
- Division of Vascular Surgery, University of Washington, Seattle, WA 98195-6410, USA
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Abstract
Aspects of people's identification with groups may be understood by borrowing theoretical ideas and measurement strategies from research on attachment in close relationships. People have mental models of the self as a group member and of groups as sources of identity and esteem. These models affect thoughts, emotions, and behaviors related to group membership. Three studies show that two dimensions of attachment to groups, attachment anxiety and avoidance, can be assessed with good reliability, validity, and over-time stability. These factors are distinct from relationship attachment and from other measures of group identification. Group attachment predicts several important outcomes, including emotions concerning the group, time and activities shared with a group, social support, collective self-esteem, and ways of resolving conflict. This conceptualization provides new insights into the nature of people's psychological ties to groups.
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Affiliation(s)
- E R Smith
- Department of Psychological Sciences, Purdue University, West Lafayette, Indiana 47907-1364, USA.
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Abstract
Aspects of people's identification with groups may be understood by borrowing theoretical ideas and measurement strategies from research on attachment in close relationships. People have mental models of the self as a group member and of groups as sources of identity and esteem. These models affect thoughts, emotions, and behaviors related to group membership. Three studies show that two dimensions of attachment to groups, attachment anxiety and avoidance, can be assessed with good reliability, validity, and over-time stability. These factors are distinct from relationship attachment and from other measures of group identification. Group attachment predicts several important outcomes, including emotions concerning the group, time and activities shared with a group, social support, collective self-esteem, and ways of resolving conflict. This conceptualization provides new insights into the nature of people's psychological ties to groups.
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Affiliation(s)
- E R Smith
- Department of Psychological Sciences, Purdue University, West Lafayette, Indiana 47907-1364, USA.
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Coats S, Whyte P, Fero ML, Lacy S, Chung G, Randel E, Firpo E, Roberts JM. A new pathway for mitogen-dependent cdk2 regulation uncovered in p27(Kip1)-deficient cells. Curr Biol 1999; 9:163-73. [PMID: 10074425 DOI: 10.1016/s0960-9822(99)80086-4] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.8] [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
BACKGROUND The ability of cyclin-dependent kinases (CDKs) to promote cell proliferation is opposed by cyclin-dependent kinase inhibitors (CKIs), proteins that bind tightly to cyclin-CDK complexes and block the phosphorylation of exogenous substrates. Mice with targeted CKI gene deletions have only subtle proliferative abnormalities, however, and cells prepared from these mice seem remarkably normal when grown in vitro. One explanation may be the operation of compensatory pathways that control CDK activity and cell proliferation when normal pathways are inactivated. We have used mice lacking the CKIs p21(Cip1) and p27(Kip1) to investigate this issue, specifically with respect to CDK regulation by mitogens. RESULTS We show that p27 is the major inhibitor of Cdk2 activity in mitogen-starved wild-type murine embryonic fibroblasts (MEFs). Nevertheless, inactivation of the cyclin E-Cdk2 complex in response to mitogen starvation occurs normally in MEFs that have a homozygous deletion of the p27 gene. Moreover, CDK regulation by mitogens is also not affected by the absence of both p27 and p21. A titratable Cdk2 inhibitor compensates for the absence of both CKIs, and we identify this inhibitor as p130, a protein related to the retinoblastoma gene product Rb. Thus, cyclin E-Cdk2 kinase activity cannot be inhibited by mitogen starvation of MEFs that lack both p27 and p130. In addition, cell types that naturally express low amounts of p130, such as T lymphocytes, are completely dependent on p27 for regulation of the cyclin E-Cdk2 complex by mitogens. CONCLUSIONS Inhibition of Cdk2 activity in mitogen-starved fibroblasts is usually performed by the CKI p27, and to a minor extent by p21. Remarkably p130, a protein in the Rb family that is not related to either p21 or p27, will directly substitute for the CKIs and restore normal CDK regulation by mitogens in cells lacking both p27 and p21. This compensatory pathway may be important in settings in which CKIs are not expressed at standard levels, as is the case in many human tumors.
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Affiliation(s)
- S Coats
- Cancer Biology Group Amgen Inc. Thousand Oaks California USA
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Gudas JM, Payton M, Thukral S, Chen E, Bass M, Robinson MO, Coats S. Cyclin E2, a novel G1 cyclin that binds Cdk2 and is aberrantly expressed in human cancers. Mol Cell Biol 1999; 19:612-22. [PMID: 9858585 PMCID: PMC83919 DOI: 10.1128/mcb.19.1.612] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A novel cyclin gene was discovered by searching an expressed sequence tag database with a cyclin box profile. The human cyclin E2 gene encodes a 404-amino-acid protein that is most closely related to cyclin E. Cyclin E2 associates with Cdk2 in a functional kinase complex that is inhibited by both p27(Kip1) and p21(Cip1). The catalytic activity associated with cyclin E2 complexes is cell cycle regulated and peaks at the G1/S transition. Overexpression of cyclin E2 in mammalian cells accelerates G1, demonstrating that cyclin E2 may be rate limiting for G1 progression. Unlike cyclin E1, which is expressed in most proliferating normal and tumor cells, cyclin E2 levels were low to undetectable in nontransformed cells and increased significantly in tumor-derived cells. The discovery of a novel second cyclin E family member suggests that multiple unique cyclin E-CDK complexes regulate cell cycle progression.
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Affiliation(s)
- J M Gudas
- Amgen Inc., Thousand Oaks, California 91320, USA
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Abstract
Cells deprived of serum mitogens will either undergo immediate cell cycle arrest or complete mitosis and arrest in the next cell cycle. The transition from mitogen dependence to mitogen independence occurs in the mid-to late G1 phase of the cell cycle and is called the restriction point. Murine Balb/c-3T3 fibroblasts deprived of serum mitogens accumulated the cyclin-dependent kinase (CDK) inhibitor p27Kip1. This was correlated with inactivation of essential G1 cyclin-CDK complexes and with cell cycle arrest in G1. The ability of specific mitogens to allow transit through the restriction point paralleled their ability to down-regulate p27, and antisense inhibition of p27 expression prevented cell cycle arrest in response to mitogen depletion. Therefore, p27 is an essential component of the pathway that connects mitogenic signals to the cell cycle at the restriction point.
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Affiliation(s)
- S Coats
- Department of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98104, USA
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Auldist MJ, Coats S, Sutherland BJ, Mayes JJ, McDowell GH, Rogers GL. Effects of somatic cell count and stage of lactation on raw milk composition and the yield and quality of Cheddar cheese. J DAIRY RES 1996; 63:269-80. [PMID: 8861348 DOI: 10.1017/s0022029900031769] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effects of somatic cell count and stage of lactation on the yield and quality of Cheddar cheese were investigated. Cheese was manufactured in a pilot scale factory using milk of low bulk milk cell count (BMCC) from herds in early (LE) and late (LL) lactation, and milk of high BMCC from herds in early (HE) and late (HL) lactation. The deleterious effect of an elevated BMCC on product yield and quality in late lactation was clear. Cheese made from LL milk was significantly superior to that made from HL milk for most yield and quality characteristics measured. Stage of lactation also affected cheese yield and quality, as evidenced by the lower recovery of fat and poorer flavour score for cheese from LL milk compared with that manufactured from LE milk. The observed differences could be explained largely by differences in raw milk composition. We conclude that the effect of stage of lactation was magnified by an elevated BMCC, and that many of the problems encountered when processing late season milk could be overcome by containing mastitis at this time.
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Affiliation(s)
- M J Auldist
- School of Agriculture, La Trobe University, Bundora VIC, Australia
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Auldist MJ, Coats S, Rogers GL, McDowell GH. Changes in the composition of milk from healthy and mastitic dairy cows during the lactation cycle. ACTA ACUST UNITED AC 1995. [DOI: 10.1071/ea9950427] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Variations in milk composition during lactation were studied in normal and mastitic dairy cows from 2 seasonally calving herds in northern Victoria. Milk yields, somatic cell counts (SCC), and concentrations of lactose, fat, total protein (TP), casein protein (CP), non-casein protein (NCP), sodium, potassium, and calcium varied considerably as lactation progressed. The basic patterns of change over lactation were similar whether cows were healthy or mastitic (SCC >3 x 105 cells/mL milk). Milk from mastitic cows had higher concentrations of TP, NCP, and sodium, but lower concentrations of fat, lactose, CP, and potassium, than milk from healthy cows, although differences were not consistently significant. The activity of the milk protease, plasmin, was positively correlated with log10SCC in both herds.
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Nourse J, Firpo E, Flanagan WM, Coats S, Polyak K, Lee MH, Massague J, Crabtree GR, Roberts JM. Interleukin-2-mediated elimination of the p27Kip1 cyclin-dependent kinase inhibitor prevented by rapamycin. Nature 1994; 372:570-3. [PMID: 7990932 DOI: 10.1038/372570a0] [Citation(s) in RCA: 744] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The cyclin-dependent kinase (Cdk) enzymes, when associated with the G1 cyclins D and E, are rate-limiting for entry into the S phase of the cell cycle. During T-cell mitogenesis, antigen-receptor signalling promotes synthesis of cyclin E and its catalytic partner, Cdk2, and interleukin-2 (IL-2) signalling activates cyclin E/Cdk2 complexes. Rapamycin is a potent immunosuppressant which specifically inhibits G1-to-S-phase progression, leading to cell-cycle arrest in yeast and mammals. Here we report that IL-2 allows Cdk activation by causing the elimination of the Cdk inhibitor protein p27Kip1, and that this is prevented by rapamycin. By contrast, the Cdk inhibitor p21 is induced by IL-2 and this induction is blocked by rapamycin. Our results show that p27Kip1 governs Cdk activity during the transition from quiescence to S phase in T lymphocytes and that p21 function may be restricted to cycling cells.
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Affiliation(s)
- J Nourse
- Program in Cancer Biology, Stanford University Medical School, California 94305
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Winningham-Major F, Staecker JL, Barger SW, Coats S, Van Eldik LJ. Neurite extension and neuronal survival activities of recombinant S100 beta proteins that differ in the content and position of cysteine residues. J Cell Biol 1989; 109:3063-71. [PMID: 2592414 PMCID: PMC2115916 DOI: 10.1083/jcb.109.6.3063] [Citation(s) in RCA: 228] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
S100 beta produced in Escherichia coli from a synthetic gene (Van Eldik, L. J., J. L. Staecker, and F. Winningham-Major. 1988. J. Biol. Chem. 263:7830-7837) stimulates neurite outgrowth and enhances cell maintenance in cultures of embryonic chick cerebral cortex neurons. In control experiments, the neurite extension activity is reduced by preincubation with antibodies made against bovine brain S100 beta. When either of the two cysteines in S100 beta are altered by site-directed mutagenesis, the resultant proteins maintain the overall biochemical properties of S100 beta, but lose both the neurite extension and neuronal survival activities. However, another S100 beta mutant, in which the relative position of one of the two cysteines was changed, had neurotrophic activity similar to that of the unmodified protein. These and other results indicate that (a) specific neurite extension activity and neuronal survival activity are two related activities inherent to the S100 beta molecule; (b) a disulfide-linked form of S100 beta is required for full biological activity, and (c) the relative position of the cysteines can be modified. These data suggest potential in vivo roles for S100 beta in the development and maintenance of neuronal function in the central nervous system, and demonstrate the feasibility of the longer term development of selective pharmacological agents based on the S100 beta structure.
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Affiliation(s)
- F Winningham-Major
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232
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