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Abhyankar MM, Orr MT, Kinsey R, Sivananthan S, Nafziger AJ, Oakland DN, Young MK, Farr L, Uddin MJ, Leslie JL, Burgess SL, Liang H, De Lima I, Larson E, Guderian JA, Lin S, Kahn A, Ghosh P, Reed S, Tomai MA, Pedersen K, Petri WA, Fox CB. Optimizing a Multi-Component Intranasal Entamoeba Histolytica Vaccine Formulation Using a Design of Experiments Strategy. Front Immunol 2021; 12:683157. [PMID: 34248966 PMCID: PMC8268010 DOI: 10.3389/fimmu.2021.683157] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Accepted: 06/07/2021] [Indexed: 11/24/2022] Open
Abstract
Amebiasis is a neglected tropical disease caused by Entamoeba histolytica. Although the disease burden varies geographically, amebiasis is estimated to account for some 55,000 deaths and millions of infections globally per year. Children and travelers are among the groups with the greatest risk of infection. There are currently no licensed vaccines for prevention of amebiasis, although key immune correlates for protection have been proposed from observational studies in humans. We previously described the development of a liposomal adjuvant formulation containing two synthetic TLR ligands (GLA and 3M-052) that enhanced antigen-specific fecal IgA, serum IgG2a, a mixed IFNγ and IL-17A cytokine profile from splenocytes, and protective efficacy following intranasal administration with the LecA antigen. By applying a statistical design of experiments (DOE) and desirability function approach, we now describe the optimization of the dose of each vaccine formulation component (LecA, GLA, 3M-052, and liposome) as well as the excipient composition (acyl chain length and saturation; PEGylated lipid:phospholipid ratio; and presence of antioxidant, tonicity, or viscosity agents) to maximize desired immunogenicity characteristics while maintaining physicochemical stability. This DOE/desirability index approach led to the identification of a lead candidate composition that demonstrated immune response durability and protective efficacy in the mouse model, as well as an assessment of the impact of each active vaccine formulation component on protection. Thus, we demonstrate that both GLA and 3M-052 are required for statistically significant protective efficacy. We also show that immunogenicity and efficacy results differ in female vs male mice, and the differences appear to be at least partly associated with adjuvant formulation composition.
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Affiliation(s)
- Mayuresh M Abhyankar
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Mark T Orr
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States.,Department of Global Health, University of Washington, Seattle, WA, United States
| | - Robert Kinsey
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States
| | - Sandra Sivananthan
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States
| | - Andrew J Nafziger
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - David N Oakland
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Mary K Young
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Laura Farr
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Md Jashim Uddin
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Jhansi L Leslie
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Stacey L Burgess
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Hong Liang
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States
| | - Ines De Lima
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States
| | - Elise Larson
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States
| | - Jeffrey A Guderian
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States
| | - Susan Lin
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States
| | - Aaron Kahn
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States
| | - Prakash Ghosh
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States
| | - Sierra Reed
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States
| | - Mark A Tomai
- 3M Corporate Research Materials Laboratory, 3M Center, St Paul, MN, United States
| | | | - William A Petri
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Christopher B Fox
- Infectious Disease Research Institute (IDRI), Seattle, WA, United States.,Department of Global Health, University of Washington, Seattle, WA, United States
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Ghosh S, Farr L, Singh A, Leaton LA, Padalia J, Shirley DA, Sullivan D, Moonah S. COP9 signalosome is an essential and druggable parasite target that regulates protein degradation. PLoS Pathog 2020; 16:e1008952. [PMID: 32960936 PMCID: PMC7531848 DOI: 10.1371/journal.ppat.1008952] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 10/02/2020] [Accepted: 09/01/2020] [Indexed: 02/06/2023] Open
Abstract
Understanding how the protozoan protein degradation pathway is regulated could uncover new parasite biology for drug discovery. We found the COP9 signalosome (CSN) conserved in multiple pathogens such as Leishmania, Trypanosoma, Toxoplasma, and used the severe diarrhea-causing Entamoeba histolytica to study its function in medically significant protozoa. We show that CSN is an essential upstream regulator of parasite protein degradation. Genetic disruption of E. histolytica CSN by two distinct approaches inhibited cell proliferation and viability. Both CSN5 knockdown and dominant negative mutation trapped cullin in a neddylated state, disrupting UPS activity and protein degradation. In addition, zinc ditiocarb (ZnDTC), a main metabolite of the inexpensive FDA-approved globally-available drug disulfiram, was active against parasites acting in a COP9-dependent manner. ZnDTC, given as disulfiram-zinc, had oral efficacy in clearing parasites in vivo. Our findings provide insights into the regulation of parasite protein degradation, and supports the significant therapeutic potential of COP9 inhibition.
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Affiliation(s)
- Swagata Ghosh
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA, United States of America
| | - Laura Farr
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA, United States of America
| | - Aditya Singh
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA, United States of America
| | - Laura-Ann Leaton
- Division of Biomedical Informatics and Personalized Medicine, University of Colorado, Aurora, CO, United States of America
| | - Jay Padalia
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA, United States of America
| | - Debbie-Ann Shirley
- Department of Pediatrics, University of Virginia School of Medicine, Charlottesville, VA, United States of America
| | - David Sullivan
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
| | - Shannon Moonah
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA, United States of America
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Farr L, Ghosh S, Moonah S. Role of MIF Cytokine/CD74 Receptor Pathway in Protecting Against Injury and Promoting Repair. Front Immunol 2020; 11:1273. [PMID: 32655566 PMCID: PMC7325688 DOI: 10.3389/fimmu.2020.01273] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/20/2020] [Indexed: 12/13/2022] Open
Abstract
Wound healing after an injury is essential for life. An in-depth understanding of the healing process is necessary to ultimately improve the currently limited treatment options for patients suffering as a result of damage to various organs and tissues. Injuries, even the most minor, trigger an inflammatory response that protects the host and activates repair pathways. In recent years, substantial progress has been made in delineating the mechanisms by which inflammatory cytokines and their receptors facilitate tissue repair and regeneration. This mini review focuses on emerging literature on the role of the cytokine macrophage migration inhibitory factor (MIF) and its cell membrane receptor CD74, in protecting against injury and promoting healing in different parts of the body.
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Affiliation(s)
- Laura Farr
- Department of Medicine, University of Virginia, Charlottesville, VA, United States
| | - Swagata Ghosh
- Department of Medicine, University of Virginia, Charlottesville, VA, United States
| | - Shannon Moonah
- Department of Medicine, University of Virginia, Charlottesville, VA, United States
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Ghosh S, Farr L, Singh A, Leaton LA, Padalia J, Sullivan DJ, Moonah SN. New parasite treatment with old alcohol drug targeting COP9 signalosome. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.00688] [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: 11/11/2022]
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Ghosh S, Padalia J, Ngobeni R, Abendroth J, Farr L, Shirley DA, Edwards T, Moonah S. Targeting Parasite-Produced Macrophage Migration Inhibitory Factor as an Antivirulence Strategy With Antibiotic-Antibody Combination to Reduce Tissue Damage. J Infect Dis 2020; 221:1185-1193. [PMID: 31677380 PMCID: PMC7325720 DOI: 10.1093/infdis/jiz579] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 11/01/2019] [Indexed: 12/13/2022] Open
Abstract
Targeting virulence factors represents a promising alternative approach to antimicrobial therapy, through the inhibition of pathogenic pathways that result in host tissue damage. Yet, virulence inhibition remains an understudied area in parasitology. Several medically important protozoan parasites such as Plasmodium, Entamoeba, Toxoplasma, and Leishmania secrete an inflammatory macrophage migration inhibitory factor (MIF) cytokine homolog, a virulence factor linked to severe disease. The aim of this study was to investigate the effectiveness of targeting parasite-produced MIF as combination therapy with standard antibiotics to reduce disease severity. Here, we used Entamoeba histolytica as the model MIF-secreting protozoan, and a mouse model that mirrors severe human infection. We found that intestinal inflammation and tissue damage were significantly reduced in mice treated with metronidazole when combined with anti-E. histolytica MIF antibodies, compared to metronidazole alone. Thus, this preclinical study provides proof-of-concept that combining antiparasite MIF-blocking antibodies with current standard-of-care antibiotics might improve outcomes in severe protozoan infections.
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Affiliation(s)
- Swagata Ghosh
- Department of Medicine, University of Virginia Health System, Charlottesville, Virginia, USA
| | - Jay Padalia
- Department of Medicine, University of Virginia Health System, Charlottesville, Virginia, USA
| | - Renay Ngobeni
- Department of Medicine, University of Virginia Health System, Charlottesville, Virginia, USA
| | - Jan Abendroth
- Seattle Structural Genomics Center for Infectious Disease, Seattle, Washington, USA
| | - Laura Farr
- Department of Medicine, University of Virginia Health System, Charlottesville, Virginia, USA
| | - Debbie-Ann Shirley
- Department of Pediatrics, University of Virginia Health System, Charlottesville, Virginia, USA
| | - Thomas Edwards
- Seattle Structural Genomics Center for Infectious Disease, Seattle, Washington, USA
| | - Shannon Moonah
- Department of Medicine, University of Virginia Health System, Charlottesville, Virginia, USA
- Correspondence: Shannon Moonah, MD, ScM, Division of Infectious Diseases, Department of Medicine, University of Virginia Health System, 345 Crispell Dr, Charlottesville, VA 22908 ()
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Farr L, Ghosh S, Jiang N, Watanabe K, Parlak M, Bucala R, Moonah S. CD74 Signaling Links Inflammation to Intestinal Epithelial Cell Regeneration and Promotes Mucosal Healing. Cell Mol Gastroenterol Hepatol 2020; 10:101-112. [PMID: 32004754 PMCID: PMC7215244 DOI: 10.1016/j.jcmgh.2020.01.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 12/31/2019] [Accepted: 01/20/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS The inflammatory response to intestinal damage promotes healing through mechanisms that are incompletely understood. Gene expression of cluster of differentiation 74 (CD74), the receptor for cytokine macrophage migration inhibitory factor, is increased in patients with inflammatory bowel disease (IBD), however, the role of CD74 signaling in intestinal inflammation remains poorly understood. The aim of this study was to determine the functional role of CD74 signaling in intestinal inflammation. METHODS We studied the characteristics of CD74 protein expression in human IBD and experimental colitis. The functional role of CD74 signaling in the intestine was investigated using cellular models; wild-type, CD74-/-, and bone marrow chimera mice; neutralizing anti-CD74 antibodies; flow cytometry; immunohistochemistry; immunofluorescence; immunoblotting; and clustered regularly interspaced short palindromic repeats and associated protein 9 technology. RESULTS In IBD patients and experimental colitis, CD74-receptor protein expression was increased in inflamed intestinal tissue, prominently in the crypt epithelial cells. By using distinct but complementary chemical and non-chemically induced mouse models of colitis with genetic and antibody neutralization approaches, we found that CD74 signaling was necessary for gut repair. Mechanistically, we found that the macrophage migration inhibitory factor cytokine, which also is increased in colitis, stimulated the CD74 receptor, enhancing intestinal epithelial cell proliferation through activation of the protein kinase B and the extracellular signal-regulated kinase pathways. Our data also suggest that CD74 signaling in immune cells was not essential for mucosal healing. CONCLUSIONS CD74 signaling is strongly activated during intestinal inflammation and protects the host by promoting epithelial cell regeneration, healing, and maintaining mucosal barrier integrity. Enhancing the CD74 pathway may represent a unique therapeutic strategy for promoting healing in IBD.
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Affiliation(s)
- Laura Farr
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Swagata Ghosh
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Nona Jiang
- Department of Medicine, Yale University, New Haven, Connecticut
| | - Koji Watanabe
- National Center for Global Health and Medicine, Tokyo, Japan
| | - Mahmut Parlak
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Richard Bucala
- Department of Medicine, Yale University, New Haven, Connecticut
| | - Shannon Moonah
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia,Correspondence Address correspondence to: Shannon Moonah, MD, ScM, Department of Medicine, University of Virginia, PO Box 801340, Charlottesville, Virginia 22908-1340. fax: (434) 243-1230.
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Abstract
Macrophage migration inhibitory factor (MIF) is a proinflammatory and proproliferative cytokine expressed in humans. MIF homologs also exist in many pathogenic protozoans, including Entamoeba, Plasmodium, Toxoplasma, and Leishmania. Production of antibodies against parasite proteins allows for the generation of assays to measure and visualize parasite infection within hosts. In this chapter, we describe how to specifically purify antibodies against Entamoeba histolytica MIF (EhMIF), and subsequently use anti-EhMIF antibodies for ELISA on mouse and human samples and for immunohistochemistry on human tissue. These methods can be applied to any protein for high-quality antibody purification.
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Affiliation(s)
- Laura Farr
- University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Koji Watanabe
- National Center for Global Health and Medicine, Shinjuku, Tokyo, Japan
| | - Shannon Moonah
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA, USA.
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Ghosh S, Jiang N, Farr L, Ngobeni R, Moonah S. Parasite-Produced MIF Cytokine: Role in Immune Evasion, Invasion, and Pathogenesis. Front Immunol 2019; 10:1995. [PMID: 31497025 PMCID: PMC6712082 DOI: 10.3389/fimmu.2019.01995] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 08/07/2019] [Indexed: 12/28/2022] Open
Abstract
Protozoan parasites represent a major threat to health and contribute significantly to morbidity and mortality worldwide, especially in developing countries. This is further compounded by lack of effective vaccines, drug resistance and toxicity associated with current therapies. Multiple protozoans, including Plasmodium, Entamoeba, Toxoplasma, and Leishmania produce homologs of the cytokine MIF. These parasite MIF homologs are capable of altering the host immune response during infection, and play a role in immune evasion, invasion and pathogenesis. This minireview outlines well-established and emerging literature on the role of parasite MIF homologs in disease, and their potential as targets for therapeutic and preventive interventions.
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Affiliation(s)
- Swagata Ghosh
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA, United States
| | - Nona Jiang
- Department of Medicine, Yale University, New Haven, CT, United States
| | - Laura Farr
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA, United States
| | - Renay Ngobeni
- Department of Environmental, Water, and Earth Sciences, Tshwane University of Technology, Pretoria, South Africa
| | - Shannon Moonah
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA, United States
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Shirley DAT, Farr L, Watanabe K, Moonah S. A Review of the Global Burden, New Diagnostics, and Current Therapeutics for Amebiasis. Open Forum Infect Dis 2018; 5:ofy161. [PMID: 30046644 PMCID: PMC6055529 DOI: 10.1093/ofid/ofy161] [Citation(s) in RCA: 170] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 07/03/2018] [Indexed: 12/21/2022] Open
Abstract
Amebiasis, due to the pathogenic parasite Entamoeba histolytica, is a leading cause of diarrhea globally. Largely an infection of impoverished communities in developing countries, amebiasis has emerged as an important infection among returning travelers, immigrants, and men who have sex with men residing in developed countries. Severe cases can be associated with high case fatality. Polymerase chain reaction–based diagnosis is increasingly available but remains underutilized. Nitroimidazoles are currently recommended for treatment, but new drug development to treat parasitic agents is a high priority. Amebiasis should be considered before corticosteroid therapy to decrease complications. There is no effective vaccine, so prevention focuses on sanitation and access to clean water. Further understanding of parasite biology and pathogenesis will advance future targeted therapeutic and preventative strategies.
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Affiliation(s)
- Debbie-Ann T Shirley
- Department of Pediatrics, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Laura Farr
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Koji Watanabe
- AIDS Clinical Center, National Center for Global Health and Medicine, Shinjuku, Tokyo, Japan
| | - Shannon Moonah
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
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Evans BAJ, James TW, James K, Cox A, Farr L, Paisey SJ, Dempster DW, Stone MD, Griffiths PA, Hugtenburg RP, Brady SM, Wells T. Preclinical assessment of a new magnetic resonance-based technique for determining bone quality by characterization of trabecular microarchitecture. Calcif Tissue Int 2014; 95:506-20. [PMID: 25380571 DOI: 10.1007/s00223-014-9922-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 10/17/2014] [Indexed: 10/24/2022]
Abstract
The utility of HR-CT to study longitudinal changes in bone microarchitecture is limited by subject radiation exposure. Although MR is not subject to this limitation, it is limited both by patient movement that occurs during prolonged scanning at distal sites, and by the signal-to-noise ratio that is achievable for high-resolution images in a reasonable scan time at proximal sites. Recently, a novel MR-based technique, fine structure analysis (FSA) (Chase et al. Localised one-dimensional magnetic resonance spatial frequency spectroscopy. PCT/US2012/068284 2012, James and Chase Magnetic field gradient structure characteristic assessment using one-dimensional (1D) spatial frequency distribution analysis. 7932720 B2, 2011) has been developed which provides both high-resolution and fast scan times, but which generates at a designated set of spatial positions (voxels) a one-dimensional signal of spatial frequencies. Appendix 1 provides a brief introduction to FSA. This article describes an initial exploration of FSA for the rapid, non-invasive characterization of trabecular microarchitecture in a preclinical setting. For L4 vertebrae of sham and ovariectomized (OVX) rats, we compared FSA-generated metrics with those from CT datasets and from CT-derived histomorphometry parameters, trabecular number (Tb.N), bone volume density (BV/TV), trabecular thickness (Tb.Th) and trabecular separation (Tb.Sp). OVX caused a reduction of the higher frequency structures that correspond to a denser trabecular lattice, while increasing the preponderance of lower frequency structures, which correspond to a more open lattice. As one example measure, the centroid of the FSA spectrum (which we refer to as fSAcB) showed strong correlation in the same region with CT-derived histomorphometry values: Tb.Sp: r -0.63, p < 0.001; Tb.N: r 0.71, p < 0.001; BV/TV: r 0.64, p < 0.001, Tb.Th: r 0.44, p < 0.05. Furthermore, we found a 17.5% reduction in fSAcB in OVX rats (p < 0.0001). In a longitudinal study, FSA showed that the age-related increase in higher frequency structures was abolished in OVX rats, being replaced with a 78-194% increase in lower frequency structures (2.4-2.8 objects/mm range), indicating a more sparse trabecular lattice (p < 0.05). The MR-based fine structure analysis enables high-resolution, radiation-free, rapid quantification of bone structures in one dimension (the specific point and direction being chosen by the clinician) of the spine.
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Affiliation(s)
- B A J Evans
- Institute of Molecular and Experimental Medicine, School of Medicine, Cardiff University, Heath Park, Cardiff, CF14 4XN, UK
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Berger AM, Agrawal S, Chamberlain J, Farr L, Kuhn B, Lynch J, Von Essen S. Sleep intervention during breast cancer chemotherapy: Fatigue and sleep disturbances outcomes. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.9580] [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: 11/20/2022] Open
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Sanford SD, Okuma JO, Pan J, Srivastava DK, West N, Farr L, Hinds PS. Gender Differences in Sleep, Fatigue, and Daytime Activity in a Pediatric Oncology Sample Receiving Dexamethasone. J Pediatr Psychol 2007; 33:298-306. [DOI: 10.1093/jpepsy/jsm110] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Couny F, Sabert H, Roberts P, Williams DP, Tomlinson A, Mangan B, Farr L, Knight J, Birks T, Russell PS. Visualizing the photonic band gap in hollow core photonic crystal fibers. Opt Express 2005; 13:558-563. [PMID: 19488385 DOI: 10.1364/opex.13.000558] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The light radiated from the guided mode of a hollow core photonic crystal fiber into free space is measured as a function of angle and wavelength. This enables the direct experimental visualization of the photonic band gap and the identification of localized modes of the core region.
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Roberts P, Couny F, Sabert H, Mangan B, Williams D, Farr L, Mason M, Tomlinson A, Birks T, Knight J, St J Russell P. Ultimate low loss of hollow-core photonic crystal fibres. Opt Express 2005; 13:236-244. [PMID: 19488348 DOI: 10.1364/opex.13.000236] [Citation(s) in RCA: 186] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Hollow-core photonic crystal fibres have excited interest as potential ultra-low loss telecommunications fibres because light propagates mainly in air instead of solid glass. We propose that the ultimate limit to the attenuation of such fibres is determined by surface roughness due to frozenin capillary waves. This is confirmed by measurements of the surface roughness in a HC-PCF, the angular distribution of the power scattered out of the core, and the wavelength dependence of the minimum loss of fibres drawn to different scales.
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Bouwmans G, Luan F, Knight J, St J Russell P, Farr L, Mangan B, Sabert H. Properties of a hollow-core photonic bandgap fiber at 850 nm wavelength. Opt Express 2003; 11:1613-1620. [PMID: 19466039 DOI: 10.1364/oe.11.001613] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We describe a hollow-core photonic bandgap fiber designed for use in the 850 nm wavelength region. The fiber has a minimum attenuation of 180dB/km at 847nm wavelength. The low-loss mode has a quasi- Gaussian intensity profile. The group-velocity dispersion of this mode passes through zero around 830nm, and is anomalous for longer wavelengths. The polarization beat length varies from 4 mm to 13 mm across the band gap. We expect this fiber to be useful for delivery of high-energy ultrashort optical pulses.
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Kakarantzas G, Ortigosa-Blanch A, Birks TA, Russell PSJ, Farr L, Couny F, Mangan BJ. Structural rocking filters in highly birefringent photonic crystal fiber. Opt Lett 2003; 28:158-160. [PMID: 12656317 DOI: 10.1364/ol.28.000158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We report what we believe is the first example of efficient rocking filter formation in polarization-maintaining photonic crystal fiber. Very high coupling efficiencies (as much as -23.5-dB suppression of the input polarization) and loss of < 0.02 dB were achieved for fibers as short as 11 mm. The filters, which we prepared by periodic mechanical twisting and heating with a scanned CO2 laser beam, are highly compact, and they are expected to be temperature stable.
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Affiliation(s)
- G Kakarantzas
- Optoelectronics Group, Department of Physics, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
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Abstract
Temperature and other circadian rhythms are disrupted following surgery and other traumatic events. During recovery, coordination between temperature rhythms and other rhythmic physiologic processes is reduced. Studies of animals and humans have shown that return of synchrony is not immediate, but that it is important in the recovery process. The purpose of this study was to test a combination of cues that have been shown to adjust the timing of circadian temperature rhythm. The combined cues consisted of timed ingestion of caffeine and protein foods and adjustment of the sleep/wake cycle. The intervention was tested in 26 age- and gender-matched maxillofacial surgery patients. Patients were randomly assigned to control or experimental groups. Circadian temperature rhythm was measured by continuous monitoring with axillary probes and miniature recorders before and after surgery. Following surgery, both experimental and control subjects displayed 24-hour circadian temperature rhythms; however, the peak-to-trough difference was decreased more following surgery in the control subjects than in the subjects who had prepared for surgery by practicing the intervention. Control subjects also had less day-to-day stability in the phase of their rhythms following surgery. These results suggest that the intervention reduced circadian disruption following surgery and provides a way for patients to prepare themselves to resist rhythm changes.
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Affiliation(s)
- L Farr
- College of Nursing, University of Nebraska Medical Center, Omaha 68198-5330, USA
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18
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Berger AM, Farr L. The influence of daytime inactivity and nighttime restlessness on cancer-related fatigue. Oncol Nurs Forum 1999; 26:1663-71. [PMID: 10573683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
PURPOSE/OBJECTIVES To identify indicators involving circadian activity/rest cycles associated with higher levels of cancer-related fatigue (CRF) during the first three chemotherapy cycles after surgery for stage I/II breast cancer. DESIGN Prospective, descriptive, repeated measures. SETTING Midwestern oncology clinics and subjects' homes. SAMPLE 72 women, ages 33-69 and free of unstable chronic illnesses, entered the study. Complete data were obtained from 30-47 subjects at each time. METHODS CRF was measured using the Piper Fatigue Scale at the start and midpoint of each chemotherapy cycle. Circadian activity/rest indicators were obtained using Mini-Motionlogger wrist actigraphs for 96 hours at the start of each treatment and for 72 hours at the midpoint of each chemotherapy cycle. MAIN RESEARCH VARIABLES Fatigue and circadian activity/rest indicators. FINDINGS Women who were less active and had increased night awakenings reported higher CRF levels at all three cycle midpoints, with the strongest association being number of night awakenings. During the third chemotherapy cycle, women who were less active during the day, took more naps, and spent more time resting during a 24-hour period experienced higher CRF. CONCLUSIONS Women whose sleep is disrupted at cycle midpoints are at risk for CRF. The cumulative effects of less daytime activity, more daytime sleep, and night awakenings are associated with higher CRF levels. IMPLICATIONS FOR NURSING PRACTICE Assessment of CRF and night awakenings at the midpoints of each chemotherapy cycle and development of nursing interventions to promote daytime activity and nighttime rest are key to managing fatigue and preventing loss of biologic rhythmicity.
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Affiliation(s)
- A M Berger
- College of Nursing, University of Nebraska Medical Center, Omaha, USA.
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19
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Harland J, White M, Drinkwater C, Chinn D, Farr L, Howel D. The Newcastle exercise project: a randomised controlled trial of methods to promote physical activity in primary care. BMJ 1999; 319:828-32. [PMID: 10496829 PMCID: PMC314213 DOI: 10.1136/bmj.319.7213.828] [Citation(s) in RCA: 207] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To evaluate the effectiveness of combinations of three methods to promote physical activity. DESIGN Randomised controlled trial. Baseline assessment with post-intervention follow up at 12 weeks and 1 year. SETTING One urban general practice, 1995-7. PARTICIPANTS 523 adults aged 40 to 64 years, randomised to four intervention groups and a control group. INTERVENTIONS Brief (one interview) or intensive (six interviews over 12 weeks) motivational interviewing based on the stages of change model of behaviour change, with or without financial incentive (30 vouchers entitling free access to leisure facilities). MAIN OUTCOME MEASURES Physical activity score; sessions of moderate and vigorous activity in the preceding four weeks. RESULTS Response rate was 81% at 12 weeks and 85% at one year. More participants in the intervention group reported increased physical activity scores at 12 weeks than controls (38% v 16%, difference 22%, 95% confidence interval for difference 13% to 32%), with a 55% increase observed in those offered six interviews plus vouchers. Vigorous activity increased in 29% of intervention participants and 11% of controls (difference 18%, 10% to 26%), but differences between the intervention groups were not significant. Short term increases in activity were not sustained, regardless of intensity of intervention. CONCLUSIONS The most effective intervention for promoting adoption of exercise was the most intensive. Even this did not promote long term adherence to exercise. Brief interventions promoting physical activity that are used by many schemes in the United Kingdom are of questionable effectiveness.
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Affiliation(s)
- J Harland
- Health Promotion Research Group, School of Health Sciences, Medical School, University of Newcastle upon Tyne, Newcastle upon Tyne NE2 4HH.
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20
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Tan A, Heaton S, Farr L, Bates J. The use of Bacillus diarrhoeal enterotoxin (BDE) detection using an ELISA technique in the confirmation of the aetiology of Bacillus-mediated diarrhoea. J Appl Microbiol 1997; 82:677-82. [PMID: 9202434 DOI: 10.1046/j.1365-2672.1997.00177.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [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: 02/04/2023]
Abstract
A commercially available ELISA kit was used for the detection of Bacillus diarrhoeal enterotoxin (BDE) in a variety of foods and faeces. The ability of isolates of Bacillus spp., including Bacillus cereus, to produce BDE in Brain Heart Infusion broth containing 0.1% glucose was also checked by use of the kit. Results show that 29 out of 31 B. cereus isolates were enterotoxigenic. Foods positive for performed BDE were always contaminated with > 10(5) B. cereus cfu g-1, but not all foods contaminated with large numbers of B. cereus were positive for BDE. Bacillus sp., other than one isolate which closely resembled B. subtilis, were negative for BDE production. Criteria for the confirmation of Bacillus-mediated diarrhoea should now include reports of symptoms and incubation periods consistent with the diarrhoeal form of food-poisoning by Bacillus spp., together with the results of tests for enterotoxigenicity of the Bacillus isolate, and detection of BDE in either the food and/or faeces.
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Affiliation(s)
- A Tan
- Department of Microbiology, University of Melbourne, Parkville, Victoria, Australia
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21
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Abstract
Circadian patterns of heart rate, systolic and diastolic blood pressure, and rate-pressure product were compared in elders with heart disease (N = 22, mean age 86 years) and a comparison group (N = 18, mean age 80 years) who did not have a cardiac diagnosis. For 4 consecutive days, automated measures of heart rate, diastolic and systolic blood pressure, and rate-pressure product were taken every 2 hours while subjects were awake. Activity-rest patterns were recorded by an observer, and demographic and medication profiles were obtained. Data were subjected to cosinor analysis, and the groups were compared on rhythmic parameters. Although the cardiac subjects were older, in poorer health, less active, and more prone to daytime napping, they exhibited more rhythms in rate-pressure product than did the comparison subjects. The cardiac group also had more synchronized oscillation of overt heart rate and systolic blood pressure rhythms. These results can be attributed to standardized times of cardiac medication administration. Attention to patterns of heart rate and systolic blood pressure in elders may suggest more appropriate times of day for conducting individual cardiac assessments.
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Affiliation(s)
- S B Dunbar
- Nell Hodgson Woodruff School of Nursing, Emory University, Atlanta, GA, USA
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22
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Smith J, Retzlaff S, Marcley D, Farr L. Chronobiotic cues as nursing interventions. Nebr Nurse 1992; 25:13. [PMID: 1470264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Abstract
A method was evaluated which has the potential to detect a food sample which has been irradiated. The technique will give an indication of the total number of viable micro-organisms present before irradiation. It is based on the comparison of an aerobic plate count (APC) with a count obtained using the Direct Epifluorescent Filter Technique (DEFT). When the APC of an irradiated sample was compared with the DEFT count on the same sample, the APC was considerably lower than that obtained by DEFT. The count of orange fluorescing cells after irradiation, however, correlated well with an APC of the same sample before irradiation. For the samples examined the DEFT count determined the viable microbial population in the sample before irradiation. The difference between the APC and the DEFT count gave the number of organisms rendered non-viable by the process.
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Affiliation(s)
- R P Betts
- Campden Food Preservation Research Association, Gloucestershire, UK
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25
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Vandenburgh HH, Karlisch P, Farr L. Maintenance of highly contractile tissue-cultured avian skeletal myotubes in collagen gel. In Vitro Cell Dev Biol 1988; 24:166-74. [PMID: 3350785 DOI: 10.1007/bf02623542] [Citation(s) in RCA: 146] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Highly contractile skeletal myotubes differentiated in tissue culture are normally difficult to maintain on collagen-coated tissue culture dishes for extended periods because of their propensity to detach as a sheet of cells from their substratum. This detachment results in the release of mechanical tension in the growing cell "sheet" and, consequently, loss of cellular protein. We developed a simple method of culturing high density contractile primary avian myotubes embedded in a collagen gel matrix (collagel) attached to either a stainless steel mesh or nylon support structure. With this system the cells are maintained in a highly contractile state for extended periods in vitro under tension. Structural integrity of the myotubes can be maintained for up to 10 d in basal medium without serum or embryo extract. Total cellular protein and myosin heavy chain accumulation in the cells can be maintained for weeks at levels which are two to three times those found in time-matched controls that are under little tension. Morphologically, the myotubes are well differentiated with structural characteristics of neonatal myofibers. This new collagel culture system should prove useful in the analysis of in vitro gene expression during myotube to myofiber differentiation and its regulation by various environmental factors such as medium growth factors, innervation, and mechanical activity.
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Affiliation(s)
- H H Vandenburgh
- Department of Pathology, Brown University, Providence, Rhode Island 02906
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26
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Shaw BG, Harding CD, Hudson WH, Farr L. Rapid Estimation of Microbial Numbers on Meat and Poultry by the Direct Epifluorescent Filter Technique. J Food Prot 1987; 50:652-657. [PMID: 30965477 DOI: 10.4315/0362-028x-50.8.652] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The direct epifluorescent filter technique (DEFT) for rapid estimation of microbial numbers was evaluated by comparison with the plate count on a variety of uncooked red meat and poultry samples. Good agreement [correlation coefficient (r) = 0.95-0.96] was obtained from samples with plate counts of 5 × 103/g or /cm2 and above from red meat carcasses (surface swabbed), aerobic or vacuum packed chill-stored joints (surface sampled - stomachered) and frozen beef (thawed stomachered). For stored and unstored raw poultry sampled by skin scraping or stomachering of muscle and skin good overall correlation (r = 0.88-0.89) was obtained between the DEFT count and the plate count in the ranges 1.1 × 103 to 1.3 × 107/cm2 (skin scraping) and 1 × 104 to 9.5 × 106/g (muscle and skin) even though the DEFT always overestimated counts on samples on which no growth had occurred (plate count <7×104/cm2 or <1×105/g). However, good linearity between DEFT and plate counts allowed use of the regression equation to obtain a good estimate of the plate count on these samples. The DEFT was unsuitable for application to poultry neck skin sampled by shaking because particulate material interfered with counting. This was also a problem with Mechanically Recovered Meat although the DEFT gave a fair estimate (r = 0.72) of the plate count on certain types (beef and veal) of this product. The DEFT was capable of providing counts within 35 to 45 min and its applicability to the rapid estimation of bacterial numbers in meat and poultry is discussed.
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Affiliation(s)
- B G Shaw
- Institute of Food Research - Bristol Laboratory, Langford, Bristol BS18 7DY, U. K
| | - C D Harding
- Institute of Food Research - Bristol Laboratory, Langford, Bristol BS18 7DY, U. K
| | - W H Hudson
- Institute of Food Research - Bristol Laboratory, Langford, Bristol BS18 7DY, U. K
| | - L Farr
- Institute of Food Research - Bristol Laboratory, Langford, Bristol BS18 7DY, U. K
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Farr L, Keene A, Samson D, Michael A. Alterations in circadian excretion of urinary variables and physiological indicators of stress following surgery. Nurs Res 1984; 33:140-6. [PMID: 6563530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Abstract
Alterations in level, timing, and coupling of circadian excretion of catecholamine metabolites, adrenal cortical hormones, sodium, potassium, creatinine, and vital signs in acute-care surgical patients were measured. Data were examined to determine if a relationship exists between the degree of circadian alteration and the subject's reentrainment to typical circadian profiles. Urine samples for assay, temperature, heart rate, and blood pressure were collected daily at 2-hour intervals from 11 consenting surgery subjects and 10 age- and sex-matched control subjects. The data indicate that certain circadian rhythms of hospitalized subjects were altered and uncoupled from external stimuli. These findings suggest that nurses (1) give individualized patient care to promote reentrainment recovery; and (2) refine nursing assessment to consider individual circadian patterns.
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