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Theobald H, Bejarano DA, Katzmarski N, Haub J, Schulte-Schrepping J, Yu J, Bassler K, Ament AL, Osei-Sarpong C, Piattini F, Vornholz L, T'Jonck W, Györfi AH, Hayer H, Yu X, Sheoran S, Al Jawazneh A, Chakarov S, Haendler K, Brown GD, Williams DL, Bosurgi L, Distler JHW, Ginhoux F, Ruland J, Beyer MD, Greter M, Bain CC, Vazquez-Armendariz AI, Kopf M, Schultze JL, Schlitzer A. Apolipoprotein E controls Dectin-1-dependent development of monocyte-derived alveolar macrophages upon pulmonary β-glucan-induced inflammatory adaptation. Nat Immunol 2024:10.1038/s41590-024-01830-z. [PMID: 38671323 DOI: 10.1038/s41590-024-01830-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 03/27/2024] [Indexed: 04/28/2024]
Abstract
The lung is constantly exposed to the outside world and optimal adaptation of immune responses is crucial for efficient pathogen clearance. However, mechanisms that lead to lung-associated macrophages' functional and developmental adaptation remain elusive. To reveal such mechanisms, we developed a reductionist model of environmental intranasal β-glucan exposure, allowing for the detailed interrogation of molecular mechanisms of pulmonary macrophage adaptation. Employing single-cell transcriptomics, high-dimensional imaging and flow cytometric characterization paired with in vivo and ex vivo challenge models, we reveal that pulmonary low-grade inflammation results in the development of apolipoprotein E (ApoE)-dependent monocyte-derived alveolar macrophages (ApoE+CD11b+ AMs). ApoE+CD11b+ AMs expressed high levels of CD11b, ApoE, Gpnmb and Ccl6, were glycolytic, highly phagocytic and produced large amounts of interleukin-6 upon restimulation. Functional differences were cell intrinsic, and myeloid cell-specific ApoE ablation inhibited Ly6c+ monocyte to ApoE+CD11b+ AM differentiation dependent on macrophage colony-stimulating factor secretion, promoting ApoE+CD11b+ AM cell death and thus impeding ApoE+CD11b+ AM maintenance. In vivo, β-glucan-elicited ApoE+CD11b+ AMs limited the bacterial burden of Legionella pneumophilia after infection and improved the disease outcome in vivo and ex vivo in a murine lung fibrosis model. Collectively these data identify ApoE+CD11b+ AMs generated upon environmental cues, under the control of ApoE signaling, as an essential determinant for lung adaptation enhancing tissue resilience.
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Affiliation(s)
- H Theobald
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - D A Bejarano
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - N Katzmarski
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - J Haub
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - J Schulte-Schrepping
- Genomics & Immunoregulation, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
- Systems Medicine, Deutsches Zentrum für Neurodegenerativen Erkrankungen (DZNE), Bonn, Germany
| | - J Yu
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - K Bassler
- Genomics & Immunoregulation, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - A L Ament
- University of Bonn, Transdisciplinary Research Area Life and Health, Organoid Biology, Life & Medical Sciences Institute, Bonn, Germany
| | - C Osei-Sarpong
- Immunogenomics & Neurodegeneration, German Center for Neurodegenerative Diseases, Bonn, Germany
| | - F Piattini
- Institute of Molecular Health Science, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - L Vornholz
- Institute of Clinical Chemistry and Pathobiochemistry, School of Medicine and Health, Technical University of Munich, Munich, Germany
- TranslaTUM, Center for Translational Cancer Research, Technical University of Munich, Munich, Germany
| | - W T'Jonck
- Centre for Inflammation Research, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh BioQuarter, Edinburgh, UK
| | - A H Györfi
- Department of Rheumatology, University Hospital Düsseldorf, Medical Faculty of Heinrich-Heine University, Düsseldorf, Germany
- Hiller Research Center, University Hospital Düsseldorf, Medical Faculty of Heinrich-Heine University, Düsseldorf, Germany
| | - H Hayer
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - X Yu
- Institute of Experimental Immunology, University of Zurich, Zurich, Switzerland
| | - S Sheoran
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - A Al Jawazneh
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Protozoa Immunology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - S Chakarov
- Shanghai Institute of Immunology, Shanghai JiaoTong School of Medicine, Shanghai, China
| | - K Haendler
- PRECISE Platform for Single Cell Genomics and Epigenomics at DZNE & University of Bonn and West German Genome Center, Bonn, Germany
- Institute of Human Genetics, University Medical Center Schleswig-Holstein, University of Luebeck & Kiel University, Luebeck, Germany
| | - G D Brown
- MRC Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - D L Williams
- Department of Surgery and Center for Inflammation, Infectious Disease and Immunity, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA
| | - L Bosurgi
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Protozoa Immunology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - J H W Distler
- Department of Rheumatology, University Hospital Düsseldorf, Medical Faculty of Heinrich-Heine University, Düsseldorf, Germany
- Hiller Research Center, University Hospital Düsseldorf, Medical Faculty of Heinrich-Heine University, Düsseldorf, Germany
| | - F Ginhoux
- Shanghai Institute of Immunology, Shanghai JiaoTong School of Medicine, Shanghai, China
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore, Singapore
- INSERM U1015, Gustave Roussy Cancer Campus, Villejuif, France
| | - J Ruland
- Institute of Clinical Chemistry and Pathobiochemistry, School of Medicine and Health, Technical University of Munich, Munich, Germany
- TranslaTUM, Center for Translational Cancer Research, Technical University of Munich, Munich, Germany
- German Center for Infection Research (DZIF), partner site Munich, Munich, Germany
- German Cancer Consortium (DKTK), partner site Munich, Munich, Germany
| | - M D Beyer
- Immunogenomics & Neurodegeneration, German Center for Neurodegenerative Diseases, Bonn, Germany
- PRECISE Platform for Single Cell Genomics and Epigenomics at DZNE & University of Bonn and West German Genome Center, Bonn, Germany
| | - M Greter
- Institute of Experimental Immunology, University of Zurich, Zurich, Switzerland
| | - C C Bain
- Centre for Inflammation Research, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh BioQuarter, Edinburgh, UK
| | - A I Vazquez-Armendariz
- University of Bonn, Transdisciplinary Research Area Life and Health, Organoid Biology, Life & Medical Sciences Institute, Bonn, Germany
| | - M Kopf
- Institute of Molecular Health Science, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - J L Schultze
- Genomics & Immunoregulation, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
- Systems Medicine, Deutsches Zentrum für Neurodegenerativen Erkrankungen (DZNE), Bonn, Germany
- PRECISE Platform for Single Cell Genomics and Epigenomics at DZNE & University of Bonn and West German Genome Center, Bonn, Germany
| | - A Schlitzer
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany.
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Seelman SL, Whitney BM, Stokes EK, Elliot EL, Griswold T, Patel K, Bloodgood S, Jones JL, Cripe J, Cornell J, Luo Y, Williams DL, Boyle MM, Cahoon J, Brennan C, Wildey LM, Grover VM, Simonson S, Crosby AJ, Bazaco MC, Viazis S. An Outbreak Investigation of Vibrio parahaemolyticus Infections in the United States Linked to Crabmeat Imported from Venezuela: 2018. Foodborne Pathog Dis 2023; 20:123-131. [PMID: 37015074 PMCID: PMC10877672 DOI: 10.1089/fpd.2022.0078] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2023] Open
Abstract
Vibrio parahaemolyticus is the leading cause of seafood-related foodborne illness globally. In 2018, the U.S. federal, state, and local public health and regulatory partners investigated a multistate outbreak of V. parahaemolyticus infections linked to crabmeat that resulted in 26 ill people and nine hospitalizations. State and U.S. Food and Drug Administration (FDA) laboratories recovered V. parahaemolyticus, Salmonella spp., and Listeria monocytogenes isolates from crabmeat samples collected from various points of distribution and conducted phylogenetic analyses of whole-genome sequencing data. Federal, state, and local partners conducted traceback investigations to determine the source of crabmeat. Multiple Venezuelan processors that supplied various brands of crabmeat were identified, but a sole firm was not confirmed as the source of the outbreak. Travel restrictions between the United States and Venezuela prevented FDA officials from conducting on-site inspections of cooked crabmeat processors. Based on investigation findings, partners developed public communications advising consumers not to eat crabmeat imported from Venezuela and placed potentially implicated firms on import alerts. While some challenges limited the scope of the investigation, epidemiologic, traceback, and laboratory evidence identified the contaminated food and country of origin, and contributed to public health and regulatory actions, preventing additional illnesses. This multistate outbreak illustrates the importance of adhering to appropriate food safety practices and regulations for imported seafood.
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Affiliation(s)
- Sharon L. Seelman
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, Maryland, USA
| | - Brooke M. Whitney
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, Maryland, USA
| | - Erin K. Stokes
- Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Elisa L. Elliot
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, Maryland, USA
| | - Taylor Griswold
- Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Kane Patel
- Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Steven Bloodgood
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, Maryland, USA
| | - Jessica L. Jones
- Gulf Coast Seafood Laboratory, Food and Drug Administration, Dauphin Island, Alabama, USA
| | - Jennifer Cripe
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, Maryland, USA
| | - Jason Cornell
- Office of the Commissioner, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Yan Luo
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, Maryland, USA
| | | | | | - Jordan Cahoon
- Maryland Department of Health, Baltimore, Maryland, USA
| | - Christy Brennan
- Virginia Department of Agriculture and Consumer Services, Richmond, Virginia, USA
| | - Laura M. Wildey
- District of Columbia Department of Health, Washington, District of Columbia, USA
- National Environmental Health Association, Denver, Colorado, USA
| | - Victoria M. Grover
- District of Columbia Department of Health, Washington, District of Columbia, USA
| | - Sean Simonson
- Louisiana Department of Health, New Orleans, Louisiana, USA
| | - Alvin J. Crosby
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, Maryland, USA
| | - Michael C. Bazaco
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, Maryland, USA
| | - Stelios Viazis
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, Maryland, USA
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Rubenstein BL, Campbell S, Meyers AR, Crum DA, Mitchell CS, Hutson J, Williams DL, Senesie SS, Gilani Z, Reynolds S, Alba B, Tavitian S, Billings K, Saintus L, Martin SB, Mainzer H. Factors That Might Affect SARS-CoV-2 Transmission Among Foreign-Born and U.S.-Born Poultry Facility Workers - Maryland, May 2020. MMWR Morb Mortal Wkly Rep 2020; 69:1906-1910. [PMID: 33332291 PMCID: PMC7745955 DOI: 10.15585/mmwr.mm6950a5] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
A 52-year-old patient with Klippel-Feil syndrome was scheduled for elective C1 dorsal laminectomy and occipitocervical stabilisation under general anaesthesia. Preoperatively she had bulbar symptoms and a history of recurrent aspiration pneumonia, but no evidence of cardiovascular disease. When she was turned prone she developed persistent tachycardia, hypotension and ST segment changes despite fluids, pressors and inotropes. Her condition improved when turned supine, but she had persistent ECG changes and a troponin rise was measured the following day. She was extubated two days postoperatively but aspirated again and subsequently died 12 days later from respiratory failure. If prone positioning is required in patients with Klippel-Feil syndrome we suggest meticulous positioning to avoid sternal compression of the heart. We also suggest thorough preoperative respiratory evaluation and elective postoperative intensive care as these patients are at high risk of developing postoperative respiratory failure.
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Affiliation(s)
- D C A Teoh
- Department ofAnaesthesia and Pain Management, The Royal Melbourne Hospital, Melbourne, Victoria, Australia
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Bose S, Romero K, Psoter KJ, Curriero FC, Chen C, Johnson CM, Kaji D, Breysse PN, Williams DL, Ramanathan M, Checkley W, Hansel NN. Association of traffic air pollution and rhinitis quality of life in Peruvian children with asthma. PLoS One 2018; 13:e0193910. [PMID: 29561906 PMCID: PMC5862476 DOI: 10.1371/journal.pone.0193910] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 02/21/2018] [Indexed: 11/18/2022] Open
Abstract
Background Air pollution exposure may contribute to rhinoconjunctivitis morbidity in children with underlying airways disease. Prior studies have not assessed rhinoconjunctivitis-related quality of life (QOL) in children with asthma chronically exposed to air pollution. Methods Children ages 9–19 years with asthma from peri-urban Peru, self-reporting rhinoconjunctivitis symptoms (n = 484), were administered the Rhinoconjunctivitis QOL Questionnaire (RQLQ) at repeated intervals over one year, with scores dichotomized into bothered (>0) and not bothered (= 0). Individual weekly exposures to particulate matter<2.5μm (PM2.5) and its black carbon (BC) component were estimated by inverse distance weighted methods. Generalized estimating equations, adjusting for covariates, estimated associations of PM2.5 and BC with QOL. Results Participants were on average 13 years old, 55% female, and majority were atopic (77%). Mean (SD) PM2.5 and BC concentrations were 21(3.2) μg/m3 and 4.4(1.5) μg/m3, respectively. In adjusted multi-pollutant models, each 10μg/m3 increase in PM2.5 was associated with increased odds of worse rhinoconjunctivitis QOL (OR;[95% CI]: 1.83;[1.33,2.52]). A 10% increase in the BC proportion was associated with higher rhinitis burden (OR;[95% CI]: 1.80;[1.22,2.66]), while increases in the non-BC component of PM did not significantly impact rhinoconjunctivitis QOL. Associations were similar regardless of atopy. Conclusion Higher PM2.5 and BC exposure is associated with worse rhinitis QOL among asthmatic children.
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Affiliation(s)
- Sonali Bose
- Johns Hopkins Department of Medicine—Baltimore, MD, United States of America
- Icahn School of Medicine at Mount Sinai, the GASP investigators, New York, NY, United States of America
| | - Karina Romero
- Johns Hopkins Department of Medicine—Baltimore, MD, United States of America
| | - Kevin J. Psoter
- Johns Hopkins Bloomberg School of Public Health—Baltimore, MD, United States of America
- Johns Hopkins School of Medicine, Department of Pediatrics—Baltimore, MD, United States of America
| | - Frank C. Curriero
- Johns Hopkins Bloomberg School of Public Health—Baltimore, MD, United States of America
| | - Chen Chen
- Johns Hopkins Bloomberg School of Public Health—Baltimore, MD, United States of America
| | - Caroline M. Johnson
- Department of Global Health, University of Washington, Seattle, WA, United States of America
| | - Deepak Kaji
- Icahn School of Medicine at Mount Sinai, the GASP investigators, New York, NY, United States of America
| | - Patrick N. Breysse
- Johns Hopkins Bloomberg School of Public Health—Baltimore, MD, United States of America
| | - D’Ann L. Williams
- Johns Hopkins Bloomberg School of Public Health—Baltimore, MD, United States of America
| | - Murugappan Ramanathan
- Johns Hopkins School of Medicine, Department of Otolaryngology—Baltimore, MD, United States of America
| | - William Checkley
- Johns Hopkins Department of Medicine—Baltimore, MD, United States of America
- Johns Hopkins Bloomberg School of Public Health—Baltimore, MD, United States of America
| | - Nadia N. Hansel
- Johns Hopkins Department of Medicine—Baltimore, MD, United States of America
- Johns Hopkins Bloomberg School of Public Health—Baltimore, MD, United States of America
- * E-mail:
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6
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Williams DL. Regenerating reptile retinas: a comparative approach to restoring retinal ganglion cell function. Eye (Lond) 2016; 31:167-172. [PMID: 27834958 DOI: 10.1038/eye.2016.224] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 11/09/2022] Open
Abstract
Transection or damage to the mammalian optic nerve generally results in loss of retinal ganglion cells by apoptosis. This cell death is seen less in fish or amphibians where retinal ganglion cell survival and axon regeneration leads to recovery of sight. Reptiles lie somewhere in the middle of this spectrum of nerve regeneration, and different species have been reported to have a significant variation in their retinal ganglion cell regenerative capacity. The ornate dragon lizard Ctenophoris ornatus exhibits a profound capacity for regeneration, whereas the Tenerife wall lizard Gallotia galloti has a more variable response to optic nerve damage. Some individuals regain visual activity such as the pupillomotor responses, whereas in others axons fail to regenerate sufficiently. Even in Ctenophoris, although the retinal ganglion cell axons regenerate adequately enough to synapse in the tectum, they do not make long-term topographic connections allowing recovery of complex visually motivated behaviour. The question then centres on where these intraspecies differences originate. Is it variation in the innate ability of retinal ganglion cells from different species to regenerate with functional validity? Or is it variances between different species in the substrate within which the nerves regenerate, the extracellular environment of the damaged nerve or the supporting cells surrounding the regenerating axons? Investigations of retinal ganglion cell regeneration between different species of lower vertebrates in vivo may shed light on these questions. Or perhaps more interesting are in vitro studies comparing axon regeneration of retinal ganglion cells from various species placed on differing substrates.
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Affiliation(s)
- D L Williams
- Department of Veterinary Medicine, University of Cambridge, Queen's Veterinary School Hospital, Cambridge, UK
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Williams DL, Wager C, Brearley J. Student attitudes regarding the educational value and welfare implications in the use of model eyes and live dogs in teaching practical fundus examination: evaluation of responses from 40 students. Open Vet J 2016; 6:172-177. [PMID: 27822453 PMCID: PMC5095501 DOI: 10.4314/ovj.v6i3.5] [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] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Accepted: 09/26/2016] [Indexed: 12/02/2022] Open
Abstract
This study sought to document student opinions on the educational value and welfare implications of use of artificial model eyes and live dogs in the training of veterinary students in examination of the canine fundus. Forty students who had undertaken a practical class on canine fundoscopy involving both use of artificial model eyes and live dogs were asked to complete a short questionnaire using a Likert scale to gauge their opinion on whether the use of live dogs and artificial eyes was very valuable (scoring 2), valuable (1), a neutral response (0), not particularly valuable (-1) or not at all valuable (-2) and to write a free text response on their views of the educational value and welfare implications of using artificial model eyes or live dogs in training for ophthalmic examination of the canine ocular fundus. Likert responses were 1.84±0.37 for using live greyhounds and 0.58±0.79 for using simulator eyes (p<0.0001). Thematic analysis of the written responses showed that while the artificial eyes were considered somewhat valuable in initial training, the live dogs were significantly preferred for their realism and the opportunity to examine the eye while handling a live animal. In conclusion, while model eyes are valuable initial training in use of the ophthalmoscope for funduscopic examination, students consider that examining the eye in the live dog is significantly more valuable and that the welfare of dogs thus used is not in their view unduly compromised.
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Affiliation(s)
- D L Williams
- Queen's Veterinary School Hospital, Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - C Wager
- Clinical Skills Center, Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - J Brearley
- Clinical Skills Center, Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
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8
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Hackstadt AJ, Butz AM, Williams DL, Diette GB, Breysse PN, Matsui EC, Peng RD. Inference for environmental intervention studies using principal stratification. Stat Med 2014; 33:4919-33. [PMID: 25164949 PMCID: PMC4224995 DOI: 10.1002/sim.6291] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 07/28/2014] [Accepted: 08/08/2014] [Indexed: 11/09/2022]
Abstract
Previous research has found evidence of an association between indoor air pollution and asthma morbidity in children. Environmental intervention studies have been performed to examine the role of household environmental interventions in altering indoor air pollution concentrations and improving health. Previous environmental intervention studies have found only modest effects on health outcomes and it is unclear if the health benefits provided by environmental modification are comparable with those provided by medication. Traditionally, the statistical analysis of environmental intervention studies has involved performing two intention-to-treat analyses that separately estimate the effect of the environmental intervention on health and the effect of the environmental intervention on indoor air pollution concentrations. We propose a principal stratification approach to examine the extent to which an environmental intervention's effect on health outcomes coincides with its effect on indoor air pollution. We apply this approach to data from a randomized air cleaner intervention trial conducted in a population of asthmatic children living in Baltimore, Maryland, USA. We find that among children for whom the air cleaner reduced indoor particulate matter concentrations, the intervention resulted in a meaningful improvement of asthma symptoms with an effect generally larger than previous studies have shown. A key benefit of using principal stratification in environmental intervention studies is that it allows investigators to estimate causal effects of the intervention for sub-groups defined by changes in the indoor air pollution concentration.
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Affiliation(s)
- A. J. Hackstadt
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205, U.S.A
| | - Arlene M. Butz
- Division of General Pediatrics, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, U.S.A
| | - D’Ann L. Williams
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205, U.S.A
| | - Gregory B. Diette
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, U.S.A
| | - Patrick N. Breysse
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205, U.S.A
| | - Elizabeth C. Matsui
- Division of Pediatric Allergy and Immunology, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, U.S.A
| | - Roger D. Peng
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205, U.S.A
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9
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Pollard SL, Williams DL, Breysse PN, Baron PA, Grajeda LM, Gilman RH, Miranda JJ, Checkley W. A cross-sectional study of determinants of indoor environmental exposures in households with and without chronic exposure to biomass fuel smoke. Environ Health 2014; 13:21. [PMID: 24655424 PMCID: PMC3978088 DOI: 10.1186/1476-069x-13-21] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 03/14/2014] [Indexed: 05/19/2023]
Abstract
BACKGROUND Burning biomass fuels indoors for cooking is associated with high concentrations of particulate matter (PM) and carbon monoxide (CO). More efficient biomass-burning stoves and chimneys for ventilation have been proposed as solutions to reduce indoor pollution. We sought to quantify indoor PM and CO exposures in urban and rural households and determine factors associated with higher exposures. A secondary objective was to identify chronic vs. acute changes in cardiopulmonary biomarkers associated with exposure to biomass smoke. METHODS We conducted a census survey followed by a cross-sectional study of indoor environmental exposures and cardiopulmonary biomarkers in the main household cook in Puno, Peru. We measured 24-hour indoor PM and CO concentrations in 86 households. We also measured PM2.5 and PM10 concentrations gravimetrically for 24 hours in urban households and during cook times in rural households, and generated a calibration equation using PM2.5 measurements. RESULTS In a census of 4903 households, 93% vs. 16% of rural vs. urban households used an open-fire stove; 22% of rural households had a homemade chimney; and <3% of rural households participated in a national program encouraging installation of a chimney. Median 24-hour indoor PM2.5 and CO concentrations were 130 vs. 22 μg/m3 and 5.8 vs. 0.4 ppm (all p<0.001) in rural vs. urban households. Having a chimney did not significantly reduce median concentrations in 24-hour indoor PM2.5 (119 vs. 137 μg/m3; p=0.40) or CO (4.6 vs. 7.2 ppm; p=0.23) among rural households with and without chimneys. Having a chimney did not significantly reduce median cook-time PM2.5 (360 vs. 298 μg/m3, p=0.45) or cook-time CO concentrations (15.2 vs. 9.4 ppm, p=0.23). Having a thatched roof (p=0.007) and hours spent cooking (p=0.02) were associated with higher 24-hour average PM concentrations. Rural participants had higher median exhaled CO (10 vs. 6 ppm; p=0.01) and exhaled carboxyhemoglobin (1.6% vs. 1.0%; p=0.04) than urban participants. CONCLUSIONS Indoor air concentrations associated with biomass smoke were six-fold greater in rural vs. urban households. Having a homemade chimney did not reduce environmental exposures significantly. Measures of exhaled CO provide useful cardiopulmonary biomarkers for chronic exposure to biomass smoke.
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Affiliation(s)
- Suzanne L Pollard
- Division of Pulmonary and Critical Care, School of Medicine, Johns Hopkins University, 1800 Orleans Ave, Suite 9121, Baltimore, MD, USA
- Program in Global Disease Epidemiology and Control, Department of International Health, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
| | - D’Ann L Williams
- Department of Environmental Health Sciences, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
| | - Patrick N Breysse
- Department of Environmental Health Sciences, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
| | - Patrick A Baron
- Department of Environmental Health Sciences, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
| | - Laura M Grajeda
- Program in Global Disease Epidemiology and Control, Department of International Health, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
| | - Robert H Gilman
- Program in Global Disease Epidemiology and Control, Department of International Health, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
- CRONICAS Center of Excellence in Chronic Diseases, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - J Jaime Miranda
- CRONICAS Center of Excellence in Chronic Diseases, Universidad Peruana Cayetano Heredia, Lima, Peru
- Departamento de Medicina, Escuela de Medicina, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - William Checkley
- Division of Pulmonary and Critical Care, School of Medicine, Johns Hopkins University, 1800 Orleans Ave, Suite 9121, Baltimore, MD, USA
- Program in Global Disease Epidemiology and Control, Department of International Health, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD, USA
- CRONICAS Center of Excellence in Chronic Diseases, Universidad Peruana Cayetano Heredia, Lima, Peru
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Treger RS, Cook AG, Rai G, Maloney DJ, Simeonov A, Jadhav A, Thomas CJ, Williams DL, Cappello M, Vermeire JJ. Oxadiazole 2-oxides are toxic to the human hookworm, Ancylostoma ceylanicum, however glutathione reductase is not the primary target. Int J Parasitol Drugs Drug Resist 2012; 2:171-177. [PMID: 22844653 DOI: 10.1016/j.ijpddr.2012.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Hookworm disease, characterized by severe anemia and cognitive and growth delays, currently affects an estimated 740 million people worldwide. Despite the prevalence of this parasitic disease, few effective drug therapies are in use today, and the heavy reliance upon benzimidazoles highlights the need for the development of novel chemotherapies. Recent work with the trematode parasite Schistosoma mansoni has identified oxadiazole 2-oxides as effective antischistosomal compounds that function by targeting and inhibiting the antioxidant enzyme, thioredoxin glutathione reductase. In this study, a related enzyme, glutathione reductase, from the human hookworm Ancylostoma ceylanicum was identified and characterized, and its in vitro activity in the presence of the oxadiazole 2-oxides was analyzed. Ex vivo worm killing assays were also conducted to establish the relationship between a given compound's effect upon worm survival and inhibition of recombinant glutathione reductase (rAceGR). Finally, the in vivo anthelminthic efficacy of furoxan (Fx) was assessed in the hamster model of hookworm infection. The predicted amino acid sequence of AceGR contained a prototypical glutathione reductase active site sequence, but no thioredoxin reductase consensus sequences, suggesting that the glutathione and thioredoxin pathways of A. ceylanicum are distinct. Although ten of the forty-two oxadiazole 2-oxides tested inhibited rAceGR activity by at least fifty percent, and fifteen compounds were toxic to parasites ex vivo, little overlap existed between these two results. We therefore suggest that AceGR is not the primary target of the oxadiazole 2-oxides in effecting parasite death. Lastly, oral treatment of A. ceylanicuminfected hamsters with furoxan resulted in significantly improved weight gains and reduced intestinal worm burdens compared to vehicle treated controls, supporting continued development of this molecule as a novel anthelminthic.
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Affiliation(s)
- R S Treger
- Program in International Child Health and Department of Pediatrics, Yale University School of Medicine, New Haven, CT
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11
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Abstract
Glucans are (1-->3)-beta-D-glucose polymers that are found in the cell wall of fungi, bacteria and plants. Glucans are known to stim ulate humoral and cell-mediated immunity in humans and animals. In addition to the potent immune stimulatory effects of (1-->3)-beta-D-glucans, there are a number of toxicological effects associated with exposure to the water-insoluble, microparticulate form of the polymer. Recent investigations have suggested a potential role for (1-->3)-beta-D-glucans in inhalational toxicity. Specifically, (1-->3)-beta-D-glucans have been implicated in the symptomatology associated with 'sick building' syndrome. The mechanisms by which (1-->3)-beta-D-glucans mediate immune stimulation and, perhaps, toxicity are currently under investigation. It is now established that (1-->3)-beta-D-glucans are recognized by macrophages and, perhaps, neutrophils and natural killer cells via a (1-->3)-beta-glucan specific receptor. Following receptor binding, glucan modulates macrophage cytokine expression. Here we review the chemistry, immunobiology and toxicity of (1-->3)-beta-D-glucans and how it may relate to effects caused by inhalation.
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Affiliation(s)
- D L Williams
- Department of Surgery James H. Quillen College of Medicine Box 70575 Johnson City TN 37614-0002 USA
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12
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Ng I, Hill AL, Williams DL, Lee K, Segal R. Randomized controlled trial comparing the McGrath videolaryngoscope with the C-MAC videolaryngoscope in intubating adult patients with potential difficult airways. Br J Anaesth 2012; 109:439-43. [PMID: 22677878 DOI: 10.1093/bja/aes145] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Difficult and failed intubations, although rarely encountered, are major causes of morbidity and mortality in the current anaesthetic practice. To reduce the incidence of difficult and failed intubations, several devices including the recently developed videolaryngoscopes are available. This randomized controlled study aims to compare the use of the McGrath videolaryngoscope with the C-MAC videolaryngoscope in adult patients with potential difficult airways. METHODS A total of 130 patients with the Mallampati grade of ≥3, requiring orotracheal intubation, were randomized to either having intubation with the McGrath videolaryngoscope or the C-MAC videolaryngoscope. The primary outcome was time to intubation. The laryngoscopic view, the number of intubation attempts, the proportion of intubation success, the ease of intubation, the haemodynamic responses to intubation, and the incidence of any complications were also recorded. RESULTS Time to successful intubation with the C-MAC videolaryngoscope was shorter when compared with the McGrath videolaryngoscope {50 s [inter-quartile range (IQR) 38-70] vs 67 s (IQR 49-108), P<0.001}, despite the McGrath videolaryngoscope providing significantly more grade 1 laryngoscopic views. The C-MAC videolaryngoscope also resulted in significantly fewer intubation attempts and greater ease of intubation when compared with the McGrath videolaryngoscope. There were no statistically significant differences in the proportion of intubation success, the number of complications, and the changes in haemodynamic responses between the two videolaryngoscopes. CONCLUSIONS The C-MAC videolaryngoscope allowed a quicker intubation time, fewer intubation attempts, and greater ease of intubation compared with the McGrath videolaryngoscope when used in patients with the Mallampati grade of ≥3.
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Affiliation(s)
- I Ng
- Department of Anaesthesia and Pain Management, Royal Melbourne Hospital, Grattan Street, Parkville, VIC 3050, Australia.
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13
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Sinclair KD, Pham TX, Farnsworth RW, Williams DL, Loc-Carrillo C, Horne LA, Ingebretsen SH, Bloebaum RD. Development of a broad spectrum polymer-released antimicrobial coating for the prevention of resistant strain bacterial infections. J Biomed Mater Res A 2012; 100:2732-8. [PMID: 22623404 DOI: 10.1002/jbm.a.34209] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Revised: 04/02/2012] [Accepted: 04/04/2012] [Indexed: 12/13/2022]
Abstract
More than 400,000 primary hip and knee replacement surgeries are performed each year in the United States. From these procedures, approximately 0.5-3% will become infected and when considering revision surgeries, this rate has been found to increase significantly. Antibiotic-resistant bacterial infections are a growing problem in patient care. This in vitro research investigated the antimicrobial potential of the polymer released, broad spectrum, Cationic Steroidal Antimicrobial-13 (CSA-13) for challenges against 5 × 10(8) colony forming units (CFU) of methicillin-resistant Staphylococcus aureus (MRSA). It was hypothesized that a weight-to-weight (w/w) concentration of 18% CSA-13 in silicone would exhibit potent bactericidal potential when used as a controlled release device coating. When incorporated into a polymeric device coating, the 18% (w/w) broad-spectrum polymer released CSA-13 antimicrobial eliminated 5 × 10(8) CFU of MRSA within 8 h. In the future, these results will be utilized to develop a sheep model to assess CSA-13 for the prevention of perioperative device-related infections in vivo.
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Affiliation(s)
- K D Sinclair
- Department of Veterans Affairs Salt Lake City Health Care System, Salt Lake City, Utah, USA.
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14
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Abstract
BACKGROUND Pain management in craniotomy patients is challenging, with mild-to-moderate pain intensity, moderate-to-high risk of postoperative nausea and vomiting (PONV), and potentially catastrophic consequences of analgesic-related side-effects. The aim of this study was to determine whether i.v. parecoxib administered at dural closure during craniotomy decreased total morphine consumption and morphine-related side-effects compared with placebo. METHODS One hundred adult patients presenting for supratentorial craniotomy under propofol/remifentanil anaesthesia were randomized to receive parecoxib, 40 mg i.v., or placebo in a double-blind manner. All patients received local anaesthetic scalp infiltration, regular i.v. paracetamol, nurse-administered morphine in the post-anaesthesia care unit (PACU) until verbal analogue pain scores were ≤4/10 and patient-controlled morphine thereafter. Morphine consumption, pain intensity, and analgesia-related side-effects were recorded during the first 24 h after operation. RESULTS Ninety-six patients (49 control and 47 parecoxib) were included in the analyses. Fifty-nine (61%) patients received morphine in the PACU and only one patient (control) did not receive any morphine in the postoperative period. There were no significant differences between the two groups in morphine consumption [20 (range: 0-102) vs 16 (range: 1-92) mg; P=0.38], pain intensity [excellent/very good pain relief in 78% of parecoxib patients; 74% of control patients (P=0.72)] or analgesia-related side-effects (PONV in 51% of parecoxib patients; 56% of control patients; P=0.55) in the first 24 h after operation. No major morbidity was recorded. CONCLUSIONS Our study demonstrated no clinical benefit to adding i.v. parecoxib to local anaesthetic scalp infiltration, i.v. paracetamol, and patient-controlled i.v. morphine after supratentorial craniotomy.
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Affiliation(s)
- D L Williams
- Department of Anaesthesia and Pain Management, Royal Melbourne Hospital, Parkville, VIC 3050, Australia.
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Chen T, Zhou G, Zhu Q, Liu X, Ha T, Kelley JL, Kao RL, Williams DL, Li C. Overexpression of vascular endothelial growth factor 165 (VEGF165) protects cardiomyocytes against doxorubicin-induced apoptosis. J Chemother 2011; 22:402-6. [PMID: 21303748 DOI: 10.1179/joc.2010.22.6.402] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Doxorubicin (Dox) has been employed in cancer chemotherapy for a few decades. However its clinical application became restricted because of dose-dependent cardiomyopathy. Recent studies suggest that Dox-induced cardiomyocyte apoptosis is a primary cause of cardiac damage. Vascular endothelial growth factor (VEGF) is a major factor for endothelial cell survival and angiogenesis. We have previously shown that VEGF165 significantly attenuates oxidative stress-induced cardiomyocytes apoptosis. We hypothesized that VEGF165 will protect the cardiomyocytes from Dox-induced apoptosis. to evaluate our hypothesis, we transfected cardiomyocytes H9c2 with adenovirus expressing VEGF165 24 hours before the cells were challenged with Dox at a concentration of 2 µm. Cardiomyocyte apoptosis was evaluated by Annexin V-FITC staining and by Western blot detection of cleaved caspase-3. The hypothesis was confirmed, and the protective mechanisms involve the inhibition of death receptor-mediated apoptosis and up-regulation of the prosurvival Akt/Nf-κb/bcl-2 signaling pathway.
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Affiliation(s)
- Tingting Chen
- Department of Pathology, Shandong University School of Medicine, 44# Wenhuaxi Road, Jinan, Shandong, 250012, China
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16
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Mazique D, Diette GB, Breysse PN, Matsui EC, McCormack MC, Curtin-Brosnan J, Williams DL, Peng RD, Hansel NN. Predictors of airborne endotoxin concentrations in inner city homes. Environ Res 2011; 111:614-7. [PMID: 21429483 PMCID: PMC3085396 DOI: 10.1016/j.envres.2011.03.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 02/24/2011] [Accepted: 03/01/2011] [Indexed: 05/22/2023]
Abstract
Few studies have assessed in home factors which contribute to airborne endotoxin concentrations. In 85 inner city Baltimore homes, we found no significant correlation between settled dust and airborne endotoxin concentrations. Certain household activities and characteristics, including frequency of dusting, air conditioner use and type of flooring, explained 36-42% of the variability of airborne concentrations. Measurements of both airborne and settled dust endotoxin concentrations may be needed to fully characterize domestic exposure in epidemiologic investigations.
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Affiliation(s)
- D Mazique
- Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
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17
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18
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Williamson SM, Scholes SFE, Welchman DDB, Dennison M, Batten CA, Williams DL, Mertens PPC, Mellor PS, Darpel KE. Bluetongue virus serotype 8-associated hydranencephaly in two calves in south-eastern England. Vet Rec 2010; 167:216-8. [PMID: 20693506 DOI: 10.1136/vr.c3302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- S M Williamson
- Veterinary Laboratories Agency, Bury St Edmunds, Rougham Hill, Bury St Edmunds, Suffolk.
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19
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Cremer JT, Williams DL, Fuller MJ, Gary CK, Piestrup MA, Pantell RH, Feinstein J, Flocchini RG, Boussoufi M, Egbert HP, Kloh MD, Walker RB. Periodic magnetic field as a polarized and focusing thermal neutron spectrometer and monochromator. Rev Sci Instrum 2010; 81:013902. [PMID: 20113108 PMCID: PMC2852448 DOI: 10.1063/1.3274512] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Accepted: 11/23/2009] [Indexed: 05/28/2023]
Abstract
A novel periodic magnetic field (PMF) optic is shown to act as a prism, lens, and polarizer for neutrons and particles with a magnetic dipole moment. The PMF has a two-dimensional field in the axial direction of neutron propagation. The PMF alternating magnetic field polarity provides strong gradients that cause separation of neutrons by wavelength axially and by spin state transversely. The spin-up neutrons exit the PMF with their magnetic spins aligned parallel to the PMF magnetic field, and are deflected upward and line focus at a fixed vertical height, proportional to the PMF period, at a downstream focal distance that increases with neutron energy. The PMF has no attenuation by absorption or scatter, as with material prisms or crystal monochromators. Embodiments of the PMF include neutron spectrometer or monochromator, and applications include neutron small angle scattering, crystallography, residual stress analysis, cross section measurements, and reflectometry. Presented are theory, experimental results, computer simulation, applications of the PMF, and comparison of its performance to Stern-Gerlach gradient devices and compound material and magnetic refractive prisms.
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Affiliation(s)
- J T Cremer
- Adelphi Technology, Inc., 2003 East Bayshore Rd., Redwood City, California 94063, USA.
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Williams DL, Fitzmaurice T, Lay L, Forster K, Hefford J, Budge C, Blackmore K, Robinson JC, Field HF. Efficacy of antiviral agents in feline herpetic keratitis: Results of anin vitrostudy. Curr Eye Res 2009; 29:215-8. [PMID: 15512970 DOI: 10.1080/02713680490504849] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [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: 10/26/2022]
Abstract
PURPOSE To determine, by a plaque reduction assay, the in vitro efficacy of novel antiviral agents in the treatment of feline herpes virus 1 (FHV-1) keratitis in the domestic cat (Felis felis). MATERIALS AND METHODS A standard plaque reduction assay was performed using a laboratory strain of FHV-1 and embryo-derived feline kidney cells to determine the in vitro efficacy of the antiviral drugs penciclovir (PCV), bromovinyldeoxyuridine (BVdU), and (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl) adenine (HPMPA) and to compare these with the drugs acyclovir (ACV) and trifluorothymidine (TFT). Efficacy was assessed by determining the dose of drug at which 50% plaque reduction was noted (ED(50)). RESULTS HPMPA was found to have greatest antiviral activity (ED(50) 0.07 microg/ml). ACV was least active (ED(50) 24 microg/ml), while TFT was active with an ED(50) of 5.7 microg/ml. PCV and BVdU had intermediate activity (ED(50) 1.6 and 1.7 microg/ml, respectively). CONCLUSIONS This study suggests that the efficacy of HPMPA, BVdU, and penciclovir in cats with herpesviral keratitis should be determined in vivo as their efficacy in vitro was substantially greater than that of acyclovir, already shown to have demonstrable but limited clinical antiviral activity.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, United Kingdom.
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21
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Andrews DT, Williams DL, Alexander KD, Lie Y. Randomised comparison of the Classic Laryngeal Mask Airway with the Cobra Perilaryngeal Airway during anaesthesia in spontaneously breathing adult patients. Anaesth Intensive Care 2009; 37:85-92. [PMID: 19157352 DOI: 10.1177/0310057x0903700107] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We tested the hypothesis that the Cobra Perilaryngeal Airway (PLA) with its high volume low-pressure cuff would provide superior airway leakage pressure compared with the Classic Laryngeal Mask Airway (LMA) in spontaneously breathing adult patients. Ninety consecutive adult patients were randomly allocated to receive one of these two supralaryngeal devices. The airway leakage pressure was higher for the PLA compared with the LMA (22 +/- 9 cmH2O vs. 18 +/- 6 cmH2O; P < 0.05). The mean airway device intracuff pressure was lower for the PLA compared to the LMA (36.1 +/- 15.2 mmHg vs. 86.3 +/- 25.3 mmHg P < 0.0001). The time required to achieve successful insertion was greater for the PLA compared with the LMA (39 +/- 21 seconds vs. 27 +/- 10 seconds; P < 0.005). The number of attempts required to achieve successful insertion and the incidence of postoperative complications were similar in both groups. The findings suggest that the PLA provides a superior airway seal at a lower intracuff pressure compared to the LMA. However the time for successful insertion may be increased.
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Affiliation(s)
- D T Andrews
- Department ofAnaesthesia and Pain Management, Royal Melbourne Hospital, Melbourne, Victoria, Australia
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22
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Abstract
A Eurasian otter (Lutra lutra) cub found in weak condition on the Isle of Harris, Scotland, developed bilateral corneal oedema 16 days after being admitted to a rehabilitation centre. It died unexpectedly on day 26. On postmortem examination, there was excess clear fluid in the body cavities and the liver was swollen with numerous pale focal lesions and petechial haemorrhages throughout. Histopathological examination revealed bundles of bacilli morphologically typical of Clostridium piliforme within hepatocytes. Comparative analysis of the nucleotide base sequence of a 16S rdna fragment amplified from the infected liver tissue revealed that it was identical to a C piliforme 16S rdna sequence. The possibility of concurrent infection with canine adenovirus type 1 was considered but none of the characteristic histopathological lesions was observed and examination of the liver by transmission electron microscopy was negative for virus particles. This appears to be the first record of Tyzzer's disease in an otter and the first in a wild animal in Britain.
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Affiliation(s)
- V R Simpson
- Wildlife Veterinary Investigation Centre, Chacewater, Truro, Cornwall tr4 8pb
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Laposky AD, Bradley MA, Williams DL, Bass J, Turek FW. Sleep-wake regulation is altered in leptin-resistant (db/db) genetically obese and diabetic mice. Am J Physiol Regul Integr Comp Physiol 2008; 295:R2059-66. [PMID: 18843095 DOI: 10.1152/ajpregu.00026.2008] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Recent epidemiological and clinical studies indicate that the control of sleep-wake states may be an important factor in the regulation of energy metabolism. Leptin is a peripherally synthesized hormone that has critical signaling properties in the brain for the control of long-term energy homeostasis. In this study, we examined the hypothesis that leptin signaling exerts a role in sleep-wake regulation and that leptin may represent an important mechanistic link in the coordination of sleep-wake states and metabolism. Sleep-wake patterns were recorded in a genetic mouse model of obesity and diabetes, the db/db mouse, which harbors a mutation in a particular isoform of the leptin receptor (long form, LRb). We found that db/db mice exhibit a variety of alterations in sleep regulation, including an increase in overall sleep time, a dramatic increase in sleep fragmentation, attenuated diurnal rhythmicity in rapid eye movement sleep and non-rapid eye movement EEG delta power (a measure of sleep homeostatic drive), and a decrease in the compensatory response to acute (i.e., 6 h) sleep deprivation. The db/db mice also generated low amounts of locomotor activity and a reduction in the diurnal rhythm of activity. These results indicate that impaired leptin signaling has deleterious effects on the regulation of sleep amount, sleep architecture, and temporal consolidation of these arousal states. In summary, leptin may represent an important molecular component in the integration of sleep, circadian rhythms, and energy metabolism.
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Affiliation(s)
- A D Laposky
- Department of Neurobiology and Physiology, Northwestern University, Center for Sleep and Circadian Biology, Evanston, Illinois, USA.
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24
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Hansel NN, Breysse PN, McCormack MC, Matsui EC, Curtin-Brosnan J, Williams DL, Moore JL, Cuhran JL, Diette GB. A longitudinal study of indoor nitrogen dioxide levels and respiratory symptoms in inner-city children with asthma. Environ Health Perspect 2008; 116:1428-32. [PMID: 18941590 PMCID: PMC2569107 DOI: 10.1289/ehp.11349] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Accepted: 07/23/2008] [Indexed: 05/04/2023]
Abstract
BACKGROUND The effect of indoor nitrogen dioxide concentrations on asthma morbidity among inner-city preschool children is uncertain. OBJECTIVES Our goal was to estimate the effect of indoor NO2 concentrations on asthma morbidity in an inner-city population while adjusting for other indoor pollutants. METHODS We recruited 150 children (2-6 years of age) with physician-diagnosed asthma from inner-city Baltimore, Maryland. Indoor air was monitored over a 72-hr period in the children's bedrooms at baseline and 3 and 6 months. At each visit, the child's caregiver completed a questionnaire assessing asthma symptoms over the previous 2 weeks and recent health care utilization. RESULTS Children were 58% male, 91% African American, and 42% from households with annual income < $25,000; 63% had persistent asthma symptoms. The mean (+/- SD) in-home NO2 concentration was 30.0 +/- 33.7 (range, 2.9-394.0) ppb. The presence of a gas stove and the use of a space heater or oven/stove for heat were independently associated with higher NO2 concentrations. Each 20-ppb increase in NO2 exposure was associated significantly with an increase in the number of days with limited speech [incidence rate ratio (IRR) = 1.15; 95% confidence interval (CI), 1.05-1.25], cough (IRR = 1.10; 95% CI, 1.02-1.18), and nocturnal symptoms (IRR = 1.09; 95% CI, 1.02-1.16), after adjustment for potential confounders. NO2 concentrations were not associated with increased health care utilization. CONCLUSIONS Higher indoor NO2 concentrations were associated with increased asthma symptoms in preschool inner-city children. Interventions aimed at lowering NO2 concentrations in inner-city homes may reduce asthma morbidity in this vulnerable population.
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Affiliation(s)
- Nadia N. Hansel
- Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Patrick N. Breysse
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | - Meredith C. McCormack
- Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Elizabeth C. Matsui
- Department of Pediatrics, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jean Curtin-Brosnan
- Department of Pediatrics, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - D’Ann L. Williams
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jennifer L. Moore
- Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jennifer L. Cuhran
- Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Gregory B. Diette
- Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
- Address correspondence to G.B. Diette, Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, 1830 East Monument St., Baltimore, MD 21205 USA. Telephone: (410) 502-7038. Fax: (410) 955-0036. E-mail:
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25
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Peña MT, Adams JE, Adams LB, Gillis TP, Williams DL, Spencer JS, Krahenbuhl JL, Truman RW. Expression and characterization of recombinant interferon gamma (IFN-gamma) from the nine-banded armadillo (Dasypus novemcinctus) and its effect on Mycobacterium leprae-infected macrophages. Cytokine 2008; 43:124-31. [PMID: 18558493 DOI: 10.1016/j.cyto.2008.04.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [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: 11/01/2007] [Revised: 03/19/2008] [Accepted: 04/28/2008] [Indexed: 10/21/2022]
Abstract
Armadillos (Dasypus novemcinctus) manifest the full histopathological spectrum of leprosy, and are hosts of choice for in vivo propagation of Mycobacterium leprae. Though potentially useful as a model of leprosy pathogenesis, few armadillo-specific reagents exist. We have identified a region of high homology to the interferon gamma (IFN-gamma) of other mammals within the recently published armadillo whole genomic sequence. cDNA was made from ConA-stimulated armadillo peripheral blood mononuclear cells (PBMC), amplified, and cloned into a pET expression vector for transformation and over-expression in Escherichia coli. The recombinant protein (rDnIFN-gamma) was characterized by western blot and its biological function confirmed with bioassays including intracellular killing of Toxoplasma gondii and induction of indoleamine 2, 3-dioxygenase activity. In using rIFN-gamma to activate macrophages from mice, humans or armadillos, similar to humans, rIFN-gamma-activated armadillo MPhi did not produce nitrite and or inhibit the viability of M. leprae in vitro. Conversely, murine rIFN-gamma-activated mouse MPhi produced high levels of nitrite and killed intracellular M. leprae in vitro. These data indicate that the response of armadillo MPhi to rDnIFN-gamma is similar to that which occurs in humans, and demonstrates a potentially important value of the armadillo as a model in leprosy research.
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Affiliation(s)
- M T Peña
- DHHS/HRSA/BPHC, National Hansen's Disease Program, LSU School of Veterinary Medicine, Microbiology Research Department, Skip Bertman Drive, Baton Rouge, LA 70803, USA
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26
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McCormack MC, Breysse PN, Hansel NN, Matsui EC, Tonorezos ES, Curtin-Brosnan J, Williams DL, Buckley TJ, Eggleston PA, Diette GB. Common household activities are associated with elevated particulate matter concentrations in bedrooms of inner-city Baltimore pre-school children. Environ Res 2008; 106:148-55. [PMID: 17927974 PMCID: PMC2291550 DOI: 10.1016/j.envres.2007.08.012] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Revised: 07/25/2007] [Accepted: 08/22/2007] [Indexed: 05/20/2023]
Abstract
Asthma disproportionately affects inner-city, minority children in the U.S. Outdoor pollutant concentrations, including particulate matter (PM), are higher in inner-cities and contribute to childhood asthma morbidity. Although children spend the majority of time indoors, indoor PM exposures have been less extensively characterized. There is a public health imperative to characterize indoor sources of PM within this vulnerable population to enable effective intervention strategies. In the present study, we sought to identify determinants of indoor PM in homes of Baltimore inner-city pre-school children. Children ages 2-6 (n=300) who were predominantly African-American (90%) and from lower socioeconomic backgrounds were enrolled. Integrated PM(2.5) and PM(10) air sampling was conducted over a 3-day period in the children's bedrooms and at a central monitoring site while caregivers completed daily activity diaries. Homes of pre-school children in inner-city Baltimore had indoor PM concentrations that were twice as high as simultaneous outdoor concentrations. The mean indoor PM(2.5) and PM(10) concentrations were 39.5+/-34.5 and 56.2+/-44.8 microg/m(3), compared to the simultaneously measured ambient PM(2.5) and PM(10) (15.6+/-6.9 and 21.8+/-9.53 microg/m(3), respectively). Common modifiable household activities, especially smoking and sweeping, contributed significantly to higher indoor PM, as did ambient PM concentrations. Open windows were associated with significantly lower indoor PM. Further investigation of the health effects of indoor PM exposure is warranted, as are studies to evaluate the efficacy of PM reduction strategies on asthma health of inner-city children.
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Affiliation(s)
| | - Patrick N. Breysse
- Department of Environmental Health Science, Johns Hopkins Bloomberg School of Public Health Department of Medicine, Baltimore, MD USA
| | - Nadia N. Hansel
- Department of Medicine, Johns Hopkins University, Baltimore, MD USA
| | | | | | | | - D’Ann L. Williams
- Department of Environmental Health Science, Johns Hopkins Bloomberg School of Public Health Department of Medicine, Baltimore, MD USA
| | - Timothy J. Buckley
- Division of Environmental Health Sciences, Ohio State University School of Public Health, Columbus, OH USA
| | | | - Gregory B. Diette
- Department of Medicine, Johns Hopkins University, Baltimore, MD USA
- Division of Environmental Health Sciences, Ohio State University School of Public Health, Columbus, OH USA
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Abstract
OBJECTIVES Previous reports have suggested that hypothyroid and diabetic patients can be predisposed to keratoconjunctivitis sicca. This study aimed to measure tear production in dogs with diabetes, hypothyroidism and hyperadrenocorticism using the Schirmer tear test and to compare these results with Schirmer tear test values for a group of normal dogs. METHODS Schirmer tear tests were performed on 16 dogs with hyperadrenocorticism, 18 with diabetes and 12 with hypothyroidism together with 100 control dogs. Corneal sensitivity was also measured in 12 of the 18 diabetic dogs with a Cochet Bonnet aesthesiometer and compared with age- and breed-matched normal dogs. RESULTS Schirmer tear test values in dogs with hypothyroidism, hyperadrenocorticism and diabetes were 12.3+/-3.2, 14.0+/-4.0 and 12.3+/-5.3 mm/minutes, respectively. Schirmer tear test values were significantly lower than that for the control group (19.6+/-4.2 mm/minutes) in all dogs with an endocrinopathy. Only in two hypothyroid dogs and three diabetics, this was manifested as profound keratoconjunctivitis sicca with Schirmer tear test value lower than 5 mm/minutes. Diabetic dogs had significantly reduced corneal sensitivity compared with a matched set of control dogs. CLINICAL SIGNIFICANCE This study shows a significant reduction in tear production in animals with diabetes mellitus, hypothyroidism and hyperadrenocorticism. Further research is needed to elucidate the mechanisms by which this reduction in tear production occurs. Assessment of tear production should be undertaken in animals diagnosed with these endocrinopathies, as these animals may progress to clinical keratoconjunctivitis sicca.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES
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Williams DL, Brancker WM. Aggravating factors in the development of ocular abnormalities in farmed Atlantic halibut (Hippoglossus hippoglossus). Vet J 2006; 172:501-5. [PMID: 16309935 DOI: 10.1016/j.tvjl.2005.08.021] [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] [Subscribe] [Scholar Register] [Accepted: 08/09/2005] [Indexed: 10/25/2022]
Abstract
Cystic lesions in the eyes of farmed halibut with a number of ocular sequelae have been reported previously with evidence that the condition can be associated with increased activity of choroidal carbonic anhydrase and elevated oxygen tension in the aqueous humour of affected fish. These changes may be compared to the 'bends' in human divers which are characterized by elevated circulating levels of nitrogen together with aggravating factors such as physical exercise. It is postulated that bubble formation and subsequent development of cysts in halibut require not only high aqueous humour oxygen tension but also the imposition of factors such as handling or intraspecific aggression which lead to bubble formation. A significantly higher incidence of lesions was noted in fish handled, weighed and measured every two weeks compared with a control group of unhandled fish, suggesting that physical activity associated with handled and possibly also intraspecific aggression is a factor in generation of ocular lesions in these fish.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, UK.
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29
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Abstract
The elevation of plasma ghrelin associated with weight loss has been taken as evidence of a role for ghrelin in the adaptive response to body weight change. However, there has been no clear experimental evidence that circulating ghrelin is suppressed by weight gain. We investigate this issue using a model of involuntary (intra-gastric gavage) overfeeding-induced obesity. Rats were first maintained at normal body weight with 4 daily tube-feedings of liquid diet (2.11 kcal/ml), each delivered at a volume of 9 ml. Gavage volume was then increased to 13 ml/feeding for 2 weeks, during which rats gained 25% of their initial body weight. Fasting plasma ghrelin levels and the response to 9- and 13-ml intra-gastric load sizes were measured during the weight-stable and overfed conditions. We found that: 1) weight gain decreased circulating ghrelin levels; 2) this response could not be attributed to additional food in the gastrointestinal tract; 3) the ghrelin response to nutrient loads was diminished in the obese vs normal-weight conditions. Having discounted diet composition and differences in gastric contents at the time of blood sampling, the decrease in ghrelin levels with overfeeding can be unambiguously attributed to physiological correlates of weight gain.
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Affiliation(s)
- D L Williams
- Department of Psychology, University of Pennsylvania, Philadelphia, USA.
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30
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Abstract
The chronic ocular lesions suffered by 50 tawny owls (Strix aluco) injured by road traffic were investigated. They included non-healing corneal erosions, cataracts and retinal scarring, and periretinal membrane formation. The intraocular pressure was significantly lower in the eyes with intraocular inflammatory pathology and higher in the eyes with irido- or cyclodialysis than in ophthalmically normal eyes. Cicatritial retinal lesions were not associated with high titres of antibodies to Toxoplasma species. The findings correlate with those observed in human beings with eye injuries due to high-speed blunt trauma.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES
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31
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Abstract
OBJECTIVE To compare the expression of major histocompatibility complex (MHC) class II antigen in the corneas of normal dogs and dogs affected with chronic superficial keratitis (CSK). METHODS MHC class II expression was determined in frozen sections of normal canine cornea and cornea from lesions of CSK by immunohistochemistry using a monoclonal antibody directed against the canine MHC class II molecule. Langerhans cell phenotype was determined morphologically and by histochemical determination of ATPase activity. To determine the influence of gamma interferon on expression of MHC class II molecules by corneal cells, corneal explants were cultured with the cytokine and MHC class II expression determined as above. RESULTS Numerous MHC class II-expressing cells were demonstrated within the stroma and epithelium of the normal corneal limbus and conjunctival epithelium while very little MHC class II expression was detected in the central region of normal canine cornea. In limbal and conjunctival epithelium, cells expressing MHC class II antigen showed ATPase activity, suggesting that they were Langerhans cells. Corneas from dogs with CSK showed MHC class II expression associated with stromal cells, some of which exhibited a dendritic morphology while most were lymphocytic. Corneal epithelial cells within the lesion also aberrantly expressed MHC class II. Corneal explants expressed MHC class II to varying degrees after differing periods of incubation with the cytokine gamma interferon. CONCLUSIONS While the normal central cornea has little MHC class II expression, aberrant expression occurs in CSK, associated with secretion of gamma interferon by infiltrating CD4-expressing lymphocytes. Although this change is likely to be a secondary feature of the CSK lesion, increased MHC class II expression may play a part in perpetuating the corneal inflammation seen in the disease.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES, England, UK.
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32
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Abstract
Leprosy is best understood as two conjoined diseases. The first is a chronic mycobacterial infection that elicits an extraordinary range of cellular immune responses in humans. The second is a peripheral neuropathy that is initiated by the infection and the accompanying immunological events. The infection is curable but not preventable, and leprosy remains a major global health problem, especially in the developing world, publicity to the contrary notwithstanding. Mycobacterium leprae remains noncultivable, and for over a century leprosy has presented major challenges in the fields of microbiology, pathology, immunology, and genetics; it continues to do so today. This review focuses on recent advances in our understanding of M. leprae and the host response to it, especially concerning molecular identification of M. leprae, knowledge of its genome, transcriptome, and proteome, its mechanisms of microbial resistance, and recognition of strains by variable-number tandem repeat analysis. Advances in experimental models include studies in gene knockout mice and the development of molecular techniques to explore the armadillo model. In clinical studies, notable progress has been made concerning the immunology and immunopathology of leprosy, the genetics of human resistance, mechanisms of nerve injury, and chemotherapy. In nearly all of these areas, however, leprosy remains poorly understood compared to other major bacterial diseases.
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Affiliation(s)
- D M Scollard
- Laboratory Research Branch, National Hansen's Disease Programs, LSU-SVM, Skip Bertman Dr., Baton Rouge, LA 70803, USA.
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Abstract
This paper describes the use of ultrasound to document ocular abnormalities occurring in farmed halibut. A cystic condition of the posterior segment of farmed halibut with a number of ocular sequelae has been reported previously. Further research to elucidate the aetiology and pathogenesis of this condition requires in vivo determination of ocular health over and above that provided by ophthalmoscopy alone. Ocular ultrasonography would appear to be an optimal technique for evaluating the presence of gas- or fluid-filled cysts in the posterior segment and retrobulbar space. The aim of this study was to evaluate this technique for investigation of the piscine eye and specifically to define the role of ultrasonography to detect gas bubble formation in the choroid of farmed halibut, a factor considered central to ocular pathology in many of these fish. In particular the study sought to assess the minimum size of halibut in which intraocular cystic lesions could be identified by ultrasonography and the minimum size of lesion identified by ocular ultrasonography. A second objective was to correlate ultrasonographic findings with lesions found at post mortem ocular examination. A number of halibut of varying sizes, with and without clinically apparent ocular lesions, were subjected to examination under anaesthesia. A proportion of these fish were subsequently sacrificed to allow post mortem ocular evaluation with the aim of correlating ultrasonographic findings with intraocular pathological defects.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES, UK.
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Abstract
A 10-year-old, female, neutered Cairn terrier was presented with a progressively enlarging, cream-white fluctuant subconjunctival swelling in the right eye. A fine-needle aspirate performed under topical anaesthesia showed that the mass contained lipomatous tissue. Orbital ultrasonography showed the mass to have a distinct border and to extend into the posterior orbit. The mass was removed via a conjunctival incision. It had a distinct capsule anteriorly, while the border of the mass was less readily identified in the posterior orbit. Histopathological examination showed the mass to be a lipoma. The dog recovered uneventfully from surgery, and no recurrence has been noted after 12 months.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES
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Adams JE, Peña MT, Gillis TP, Williams DL, Adams LB, Truman RW. Expression of nine-banded armadillo (Dasypus novemcinctus) interleukin-2 in E. coli. Cytokine 2005; 32:219-25. [PMID: 16338142 DOI: 10.1016/j.cyto.2005.09.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [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: 06/15/2005] [Revised: 08/26/2005] [Accepted: 09/01/2005] [Indexed: 10/25/2022]
Abstract
The nine-banded armadillo (Dasypus novemcinctus) is the only immunologically intact animal that regularly develops lepromatous-type leprosy when inoculated with Mycobacterium leprae. However, the ability to exploit this model for understanding the pathogenesis of leprosy has been limited by a lack of suitable immunological reagents. Recently, efforts began to sequence the entire armadillo genome, and this sequence information will help make possible the development of a wide array of new immunological reagents suitable for use with armadillos. Using the available sequence data, a region of high homology to interleukin-2 of other mammals was identified. Primers were designed to amplify the coding region corresponding to the mature peptide and its exact sequence was confirmed. cDNA was made from ConA-stimulated armadillo PBMC. The amplified coding region was sub-cloned into a pET expression vector and transformed into Escherichia coli for over-expression. The subsequent product was characterized by SDS-PAGE and bioassays. Tritiated thymidine incorporation by CTLL-2 and armadillo lymphoblasts confirmed functionality of the recombinant product. The advent of the D. novemcinctus genome sequence and subsequent generation of immunological tools will assist in advancing the armadillo as a translational model for leprosy.
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Affiliation(s)
- J E Adams
- Laboratory Research Branch National Hansen's Disease Programs, Louisiana State University, School of Veterinary Medicine, Skip Bertman Drive, Baton Rouge, LA 70803, USA
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Williams DL, Robinson JC, Lay E, Field H. Efficacy of topical aciclovir for the treatment of feline herpetic keratitis: results of a prospective clinical trial and data from in vitro investigations. Vet Rec 2005; 157:254-7. [PMID: 16127135 DOI: 10.1136/vr.157.9.254] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [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: 11/04/2022]
Abstract
This study aimed to evaluate the efficacy of topical ophthalmic aciclovir applied five times daily as a treatment for feline herpesvirus type 1 (FHV-1) keratitis in a group of cats in a first-opinion practice setting. Cats with ocular signs indicative of FHV-1 or Chlamydophila species infection, predominantly conjunctivitis and keratitis, were tested for FHV-1 antigen using an immunofluorescent technique on air-dried conjunctival swabs. They were first treated with topical chlortetracycline with efficacy against Chlamydophila species and then, in cases positive for FHV-1, with topical aciclovir. The time to recovery was determined and illustrated using a Kaplan-Meier plot. Three cats were infected with Chlamydophila species and showed a median time to recovery of 14 days (95 per cent confidence interval [CI] 10 to 18 days), while 30 cats infected with FHV-1 showed a median time to recovery of 12 days (95 per cent CI 10 to 14 days). The drug dose at which 50 per cent plaque reduction (ED50) occurred in a standard plaque reduction assay was determined in an in vitro study. This showed a mean (SD) ED50 of aciclovir of 25 (3.5) mg/ml compared with 0.4 (0.05) mg/ml for trifluorothymidine, a drug known to be efficacious against FHV-1. The study shows that even though aciclovir is generally considered to lack efficacy against ocular FHV-1 infection, when used frequently it can have a beneficial effect in FHV-1 conjunctivitis and keratitis.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES
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37
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Abstract
Eyes from 88 otters found dead in south-west England between 1990 and 2000, were collected as part of a larger pathological study. Histopathological examination of 131 eyes revealed dysplastic changes such as rosetting and folding in the retinas of 26 of the otters. In the eyes of 42 of the otters there were postmortem and fixation-induced retinal detachment which complicated the differentiation of dysplastic from normal retina, but 11 eyes had folds which probably indicated a dysplastic pathology. The eyes of 18 of the otters had inflammatory or autolytic changes which precluded a definitive evaluation of their dysplastic status. Liver samples from 55 of the otters were analysed for a range of polychlorinated hydrocarbons and for vitamin A. The otters with dysplastic retinas had significantly lower concentrations of vitamin A and higher concentrations of dieldrin than the otters with normal retinas.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, University of Cambridge
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38
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Abstract
We have previously documented ocular abnormalities in farmed halibut and reported that the production of gas-filled posterior segment cysts appears to be central in the pathogenesis of many, if not all of the signs in these eyes. In a number of fish, gas bubbles may be seen in the anterior chamber of the eye, especially after trauma or strenuous exertion associated with handling. A knowledge of the composition of this gas is important in understanding fully the mechanism of gas and cyst production. Here we report investigations into the composition of gas in the globes of normal fish, fish in which intraocular cysts have been documented previously by ultrasonography and fish where post-mortem examination demonstrated both gas- and fluid-filled choroidal cysts. High levels of oxygen were demonstrated in samples of aqueous from all fish but fish with affected eyes had a statistically significantly higher partial pressure of oxygen than did fish with normal eyes.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, Madingley Road, Cambridge CB3 OES, UK.
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39
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Abstract
OBJECTIVE In this study 2000 dogs were examined ophthalmoscopically to determine presence of cataract. MATERIALS AND METHODS The dogs examined were predominantly from veterinary hospital populations but also from the Waltham Center For Pet Nutrition, rehoming charities and breeding kennels. Prevalence of cataract was thus determined for different age groups (year cohorts). The age at which prevalence of cataract was 50% (C50) was determined indirectly from a fitted prevalence curve. RESULTS The mean +/- standard deviation of C50 for all dogs in the study was 9.4 +/- 3.3 years. All dogs over 13.5 years were affected by some degree of lens opacity. C50 was determined for animals of different genders and different breeds. For dogs of six breeds sufficient data were available for calculation of breed-specific C50. In these dogs C50 was positively correlated with longevity with a least squares correlation coefficient of 0.74. CONCLUSION The study yields novel findings regarding the prevalence and incidence of cataract in the dog and forms the basis for considerable further work on the epidemiology and pathophysiology of age-related cataract in the dog.
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Affiliation(s)
- D L Williams
- Queen's Veterinary School Small Animal Hospital, Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK.
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40
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Williams DL, Bowers RR, Bartness TJ, Kaplan JM, Grill HJ. Brainstem melanocortin 3/4 receptor stimulation increases uncoupling protein gene expression in brown fat. Endocrinology 2003; 144:4692-7. [PMID: 12960080 DOI: 10.1210/en.2003-0440] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [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: 11/19/2022]
Abstract
Central administration of melanocortin 3 and 4 receptor (MC3/4-R) agonists increases energy expenditure, with the hypothalamus commonly held as the primary site of action. It is also clear, however, that MC4-R are expressed in caudal brainstem structures of relevance to the control of energy expenditure. Three experiments investigated whether hindbrain MC-R contribute to the energy expenditure effects of central MC3/4-R agonist treatments; in each, we examined the effect of fourth intracerebroventricular (i.c.v.) administration of a MC3/4-R agonist, MTII (three injections, each separated by 12 h), on uncoupling protein 1 (UCP-1) gene expression in brown adipose tissue (BAT). First, we compared the effects of fourth and third i.c.v. administration of MTII and found that the hindbrain and forebrain treatments were equally effective at elevating UCP-1 mRNA expression in BAT compared with the respective vehicle-treated group results. A second experiment demonstrated that the fourth i.c.v. MTII-induced rise in UCP-1 expression was mediated by sympathetic outflow to BAT by showing that this response was abolished by surgical denervation of BAT. In the third experiment, we showed that chronic decerebrate rats, like their neurologically intact controls, elevated UCP-1 mRNA expression in response to fourth i.c.v. MTII administration. Taken together, the results indicate that: 1) there is an independent caudal brainstem MC3/4-R trigger for a sympathetically stimulated elevation in BAT UCP-1 gene expression, and 2) the MTII-induced rise in UCP-1 expression can be mediated by circuitry intrinsic to the caudal brainstem and spinal cord.
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MESH Headings
- Adipose Tissue, Brown/innervation
- Adipose Tissue, Brown/physiology
- Animals
- Brain Stem/metabolism
- Carrier Proteins/genetics
- Decerebrate State/metabolism
- Energy Metabolism/drug effects
- Energy Metabolism/physiology
- Gene Expression/physiology
- Injections, Intraventricular
- Ion Channels
- Male
- Membrane Proteins/genetics
- Mitochondrial Proteins
- Peptides, Cyclic/administration & dosage
- Prosencephalon/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, Melanocortin, Type 3/drug effects
- Receptor, Melanocortin, Type 3/physiology
- Receptor, Melanocortin, Type 4/drug effects
- Receptor, Melanocortin, Type 4/physiology
- Rhombencephalon/metabolism
- Sympathetic Nervous System/physiology
- Uncoupling Protein 1
- alpha-MSH/administration & dosage
- alpha-MSH/analogs & derivatives
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Affiliation(s)
- D L Williams
- Department of Psychology, University of Pennsylvania, Philadelphia, USA.
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41
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Williams DL. Fees for RCVS members retired ... and new. Vet Rec 2003; 152:604. [PMID: 12762497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
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Abstract
Twenty eyes of 10 dogs with keratoconjunctivitis sicca (KCS) were treated by occlusion of the ventral nasolacrimal punctum with a silicone punctal plug in order to increase the volume of the remaining tear lake. Punctal size was measured using a commercially available punctal gauge and the appropriate sized plug was inserted under local anaesthesia. Seven dogs showed an increase in Schirmer tear test I (STT) value. STT values immediately prior to plug placement were 2.3 +/- 1.7 mm/minute. STT values with punctal occlusion were 6.1 +/- 4.1 mm/minute, giving a mean increase of 3.8 +/- 2.7 mm/minute (P<0.001). In 14 eyes of eight dogs, the increase in STT values was accompanied by a clinical improvement in the appearance of the ocular surface. In the three dogs with no increase in STT values, the use of punctal plugs reduced the frequency of artificial tear replacement therapy required to maintain a healthy ocular surface. These results show that use of punctal plugs in dogs with KCS may be appropriate where other lacrimomimetic medications have been unsuccessful.
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Affiliation(s)
- D L Williams
- Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES
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43
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Abstract
This article describes a new set of revised standards for the medical laboratory, which have been produced by Clinical Pathology Accreditation (UK) Ltd (CPA). The original standards have been in use since 1992 and it was recognised that extensive revision was required. A standards revision group was established by CPA and this group used several international standards as source references, so that the resulting new standards are compatible with the most recent international reference sources. The aim is to make the assessment of medical laboratories as objective as possible in the future. CPA plans to introduce these standards in the UK in 2003 following extensive consultation with professional bodies, piloting in selected laboratories, and training of assessors.
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Affiliation(s)
- D Burnett
- Lindens Lodge, Bradford Place, Penarth CF64 1LA, UK.
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de La Llera-Moya M, Connelly MA, Drazul D, Klein SM, Favari E, Yancey PG, Williams DL, Rothblat GH. Scavenger receptor class B type I affects cholesterol homeostasis by magnifying cholesterol flux between cells and HDL. J Lipid Res 2001; 42:1969-78. [PMID: 11734569] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
Results from several laboratories clearly indicate that expression of scavenger receptor class B type I (SR-BI) enhances the bidirectional flux of cholesterol between cells and lipoproteins. Because the activity of HMG-CoA reductase, the key enzyme in cholesterol biosynthesis, is regulated by cell cholesterol content, we designed experiments to investigate the effect of SR-BI expression on the activity of this enzyme and on net cellular cholesterol mass. In addition, we compared the function of SR-BI with its human homolog, CD36 and LIMPII analogous 1. Our experiments demonstrate that both receptors enhance the flux of unesterified or free cholesterol bidirectionally, down a concentration gradient. Receptor-mediated cholesterol flux can effectively modulate multiple aspects of cellular cholesterol metabolism, including the pool that regulates the activity of HMG-CoA reductase. We also found that constitutive expression of SR-BI alters the steady state level of cellular cholesterol and phospholipid when SR-BI-expressing cells are maintained in medium containing serum lipoproteins. All of these effects are proportional to the level of receptor on the cell surface. These data indicate that the level of SR-BI expression determines both the rate of free cholesterol flux and the steady state level of cellular cholesterol.
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Affiliation(s)
- M de La Llera-Moya
- Division of Gastroenterology and Nutrition, Department of Pediatrics, Abramson Research Center, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-4318, USA.
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Thuahnai ST, Lund-Katz S, Williams DL, Phillips MC. Scavenger receptor class B, type I-mediated uptake of various lipids into cells. Influence of the nature of the donor particle interaction with the receptor. J Biol Chem 2001; 276:43801-8. [PMID: 11564739 DOI: 10.1074/jbc.m106695200] [Citation(s) in RCA: 99] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Scavenger receptor (SR)-BI is the first molecularly defined receptor for high density lipoprotein (HDL) and it can mediate the selective uptake of cholesteryl ester into cells. To elucidate the molecular mechanisms by which SR-BI facilitates lipid uptake, we examined the connection between lipid donor particle binding and lipid uptake using kidney COS-7 cells transiently transfected with SR-BI. We systematically compared the uptake of [(3)H]cholesteryl oleoyl ether (CE) and [(14)C]sphingomyelin (SM) from apolipoprotein (apo) A-I-containing reconstituted HDL (rHDL) particles and apo-free lipid donor particles. Although both types of lipid donor could bind to SR-BI, only apo-containing lipid donors exhibited preferential delivery of CE over SM (i.e. nonstoichiometric lipid uptake). In contrast, apo-free lipid donor particles (phospholipid unilamellar vesicles, lipid emulsion particles) gave rise to stoichiometric lipid uptake due to interaction with SR-BI. This apparent whole particle uptake was not due to endocytosis, but rather fusion of the lipid components of the lipid donor with the cell plasma membrane; this process is perhaps mediated by a fusogenic motif in the extracellular domain of SR-BI. The interaction of apoA-I with SR-BI not only prevents fusion of the lipid donor with the plasma membrane but also allows the optimal selective lipid uptake. A comparison of rHDL particles containing apoA-I and apoE-3 showed that while both particles bound equally well to SR-BI, the apoA-I particle gave approximately 2-fold greater CE selective uptake. Catabolism of all major HDL lipids can occur via SR-BI with the relative selective uptake rate constants for CE, free cholesterol, triglycerides (triolein), and phosphatidylcholine being 1, 1.6, 0.7, and 0.2, respectively. It follows that a putative nonpolar channel created by SR-BI between the bound HDL particle and the cell plasma membrane is better able to accommodate the uptake of neutral lipids (e.g. cholesterol) relative to polar phospholipids.
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Affiliation(s)
- S T Thuahnai
- GI/Nutrition Division, The Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-4318, USA
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Liu Q, Guan XM, Martin WJ, McDonald TP, Clements MK, Jiang Q, Zeng Z, Jacobson M, Williams DL, Yu H, Bomford D, Figueroa D, Mallee J, Wang R, Evans J, Gould R, Austin CP. Identification and characterization of novel mammalian neuropeptide FF-like peptides that attenuate morphine-induced antinociception. J Biol Chem 2001; 276:36961-9. [PMID: 11481330 DOI: 10.1074/jbc.m105308200] [Citation(s) in RCA: 217] [Impact Index Per Article: 9.4] [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: 11/06/2022] Open
Abstract
The two mammalian neuropeptides NPFF and NPAF have been shown to have important roles in nociception, anxiety, learning and memory, and cardiovascular reflex. Two receptors (FF1 and FF2) have been molecularly identified for NPFF and NPAF. We have now characterized a novel gene designated NPVF that encodes two neuropeptides highly similar to NPFF. NPVF mRNA was detected specifically in a region between the dorsomedial and ventromedial hypothalamic nuclei. NPVF-derived peptides displayed higher affinity for FF1 than NPFF-derived peptides, but showed poor agonist activity for FF2. Following intracerebral ventricular administration, a NPVF-derived peptide blocked morphine-induced analgesia more potently than NPFF in both acute and inflammatory models of pain. In situ hybridization analysis revealed distinct expression patterns of FF1 and FF2 in the rat central nervous system. FF1 was broadly distributed, with the highest levels found in specific regions of the limbic system and the brainstem where NPVF-producing neurons were shown to project. FF2, in contrast, was mostly expressed in the spinal cord and some regions of the thalamus. These results indicate that the endogenous ligands for FF1 and FF2 are NPVF- and NPFF-derived peptides, respectively, and suggest that the NPVF/FF1 system may be an important part of endogenous anti-opioid mechanism.
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Affiliation(s)
- Q Liu
- Department of Pharmacology, Merck Research Laboratories, West Point, Pennsylvania 19486, USA.
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Abstract
A number of S-nitrosothiols react rapidly with the Fe(II) complexes of 2,3-dimercapto-1-propanesulfonic acid (DMPS) and of N-methyl-D-glucamine dithiocarbamate (MGD), transferring the NO group directly to the iron centres.
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Affiliation(s)
- A R Butler
- Department of Chemistry, University of St. Andrews, St. Andrews, Fife, UK KY16 9ST
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Lowman DW, Williams DL. A proton nuclear magnetic resonance method for the quantitative analysis on a dry weight basis of (1-->3)-beta-D-glucans in a complex, solvent-wet matrix. J Agric Food Chem 2001; 49:4188-4191. [PMID: 11559108 DOI: 10.1021/jf010435l] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Health benefits of the polysaccharide (1-->3)-beta-D-glucan, reported to induce immunobiological, hypocholesterolemic, and hypoglycemic effects in humans and animals, have made the isolation, characterization, and assay of a viable glucan product critical. A new analytical method, based on internal standard proton NMR analysis, for the assay of solvent-wet samples containing (1-->3)-beta-D-glucan is presented. The method enables glucan identification, provides a solvent-free assay, and improves upon the previous multistep extraction and lyophilization procedure by reducing the 1-2 day analysis time to 1-2 h. NMR offers a rapid method for quantifying the glucan in commercial samples, such as nutraceuticals, as well as industrial samples enabling better evaluation of the efficacy of these carbohydrates in health-related applications.
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Affiliation(s)
- D W Lowman
- Global Analytical Services, Eastman Chemical Company, Kingsport, Tennessee 37662-5150, USA.
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Ahrén IL, Williams DL, Rice PJ, Forsgren A, Riesbeck K. The importance of a beta-glucan receptor in the nonopsonic entry of nontypeable Haemophilus influenzae into human monocytic and epithelial cells. J Infect Dis 2001; 184:150-8. [PMID: 11424011 DOI: 10.1086/322016] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2000] [Revised: 04/18/2001] [Indexed: 11/03/2022] Open
Abstract
Previous reports showed that nontypeable Haemophilus influenzae (NTHi) reside in macrophage-like cells in human adenoid tissue. This study investigated the ability of nonopsonized NTHi and encapsulated H. influenzae type b (Hib) to enter human monocytic and epithelial cells. The number of intracellular bacteria was determined by a viability assay and flow cytometry. To characterize the mechanisms responsible for the internalization of NTHi, different inhibitors of surface molecules, receptor turnover, and the cytoskeleton were used. Hib were found in monocytic cells at very low numbers (<100 bacteria/2x105 cells). In contrast, a great variation in intracellular numbers was detected between the different NTHi isolates (range, 0.0007%-0.28% of the inoculum for monocytes and 0.053%-3.5% for epithelial cells). NTHi entered human monocytic and epithelial cells via a receptor-mediated endocytosis involving mainly a beta-glucan receptor that could be blocked by laminarin.
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Affiliation(s)
- I L Ahrén
- Department of Medical Microbiology, Malmö University Hospital, Lund University, Malmö, Sweden
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Thomas GA, Williams DL, Soper SA. Capillary electrophoresis-based heteroduplex analysis with a universal heteroduplex generator for detection of point mutations associated with rifampin resistance in tuberculosis. Clin Chem 2001; 47:1195-203. [PMID: 11427449] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
BACKGROUND Slab gel heteroduplex analysis (HDA), a popular scanning method for genetic mutations, uses DNA fragments typically generated by PCR to create homo- and heteroduplex molecules with conformational differences and sequence-dependent electrophoretic profiles. Use of a universal heteroduplex generator (UHG) enhances the subtle variations caused by single-base substitutions. METHODS The HDA-UHG slab gel format was modified for an efficient capillary-based method. The effect of staining dyes TOPRO5 and YOPRO1 on the analysis of heteroduplexes was studied, as well as ultraviolet absorbance and laser-induced fluorescence (LIF) detection methods. In addition, the entangled polymers hydroxyethyl cellulose, methyl cellulose, and linear polyacrylamide were evaluated as separation matrices. RESULTS This assay was able to detect the presence of Mycobacterium tuberculosis and its rifampin susceptibility directly from clinical specimens in dramatically reduced analysis time (30 min vs 2.5 h). Optimized conditions included 0.3% methyl cellulose as the separation matrix, on-line staining using 1 micromol/L YOPRO1, and LIF detection for quantitative and reproducible analysis of single-base substitutions in the rifampin resistance-determining region of rpoB that give rise to the rifampin-resistant phenotype of M. tuberculosis. We generated 95% confidence limits using the wild-type sequence and used these limits to determine rifampin susceptibility in samples. CONCLUSIONS Capillary electrophoresis, combined with the HDA-UHG technique, may be of value for rapid and efficient clinical diagnosis of rifampin-resistant tuberculosis strains.
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Affiliation(s)
- G A Thomas
- Chemistry Department, Louisiana State University, Baton Rouge, LA 70803, USA
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