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Mitchell SJ, Phillips GD, Tench B, Li Y, Belelli D, Martin SJ, Swinny JD, Kelly L, Atack JR, Paradowski M, Lambert JJ. Neurosteroid Modulation of Synaptic and Extrasynaptic GABA A Receptors of the Mouse Nucleus Accumbens. Biomolecules 2024; 14:460. [PMID: 38672476 PMCID: PMC11048561 DOI: 10.3390/biom14040460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 03/29/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024] Open
Abstract
The recent approval of formulations of the endogenous neurosteroid allopregnanolone (brexanolone) and the synthetic neuroactive steroid SAGE-217 (zuranolone) to treat postpartum depression (PPD) has encouraged further research to elucidate why these potent enhancers of GABAAR function are clinically effective in this condition. Dopaminergic projections from the ventral tegmental area (VTA) to the nucleus accumbens are associated with reward/motivation and brain imaging studies report that individuals with PPD show reduced activity of this pathway in response to reward and infant engagement. However, the influence of neurosteroids on GABA-ergic transmission in the nucleus accumbens has received limited attention. Here, we investigate, in the medium spiny neurons (MSNs) of the mouse nucleus accumbens core, the effect of allopregnanolone, SAGE-217 and other endogenous and synthetic steroids of interest on fast phasic and tonic inhibition mediated by synaptic (α1/2βγ2) and extrasynaptic (α4βδ) GABAARs, respectively. We present evidence suggesting the resident tonic current results from the spontaneous opening of δ-GABAARs, where the steroid-enhanced tonic current is GABA-dependent. Furthermore, we demonstrate local neurosteroid synthesis in the accumbal slice preparation and reveal that GABA-ergic neurotransmission of MSNs is influenced by an endogenous neurosteroid tone. Given the dramatic fluctuations in allopregnanolone levels during pregnancy and postpartum, this neurosteroid-mediated local fine-tuning of GABAergic transmission in the MSNs will probably be perturbed.
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Affiliation(s)
- Scott J. Mitchell
- Division of Cellular & Systems Medicine, School of Medicine, Medical Sciences Institute, Dundee University, Dow Street, Dundee DD1 5HL, UK; (S.J.M.); (G.D.P.); (B.T.); (Y.L.); (D.B.); (S.J.M.)
| | - Grant D. Phillips
- Division of Cellular & Systems Medicine, School of Medicine, Medical Sciences Institute, Dundee University, Dow Street, Dundee DD1 5HL, UK; (S.J.M.); (G.D.P.); (B.T.); (Y.L.); (D.B.); (S.J.M.)
| | - Becks Tench
- Division of Cellular & Systems Medicine, School of Medicine, Medical Sciences Institute, Dundee University, Dow Street, Dundee DD1 5HL, UK; (S.J.M.); (G.D.P.); (B.T.); (Y.L.); (D.B.); (S.J.M.)
| | - Yunkai Li
- Division of Cellular & Systems Medicine, School of Medicine, Medical Sciences Institute, Dundee University, Dow Street, Dundee DD1 5HL, UK; (S.J.M.); (G.D.P.); (B.T.); (Y.L.); (D.B.); (S.J.M.)
| | - Delia Belelli
- Division of Cellular & Systems Medicine, School of Medicine, Medical Sciences Institute, Dundee University, Dow Street, Dundee DD1 5HL, UK; (S.J.M.); (G.D.P.); (B.T.); (Y.L.); (D.B.); (S.J.M.)
| | - Stephen J. Martin
- Division of Cellular & Systems Medicine, School of Medicine, Medical Sciences Institute, Dundee University, Dow Street, Dundee DD1 5HL, UK; (S.J.M.); (G.D.P.); (B.T.); (Y.L.); (D.B.); (S.J.M.)
| | - Jerome D. Swinny
- School of Pharmacy & Biomedical Sciences, St. Michael’s Building, University of Portsmouth, White Swan Road, Portsmouth PO1 2DT, UK; (J.D.S.); (L.K.)
| | - Louise Kelly
- School of Pharmacy & Biomedical Sciences, St. Michael’s Building, University of Portsmouth, White Swan Road, Portsmouth PO1 2DT, UK; (J.D.S.); (L.K.)
| | - John R. Atack
- Main Building, Medicines Discovery Institute, Park Place, Cardiff University, Cardiff, CF10 3AT, UK; (J.R.A.); (M.P.)
| | - Michael Paradowski
- Main Building, Medicines Discovery Institute, Park Place, Cardiff University, Cardiff, CF10 3AT, UK; (J.R.A.); (M.P.)
| | - Jeremy J. Lambert
- Division of Cellular & Systems Medicine, School of Medicine, Medical Sciences Institute, Dundee University, Dow Street, Dundee DD1 5HL, UK; (S.J.M.); (G.D.P.); (B.T.); (Y.L.); (D.B.); (S.J.M.)
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Zhang Z, Villalobos EM, Nikaido S, Martin SJ. Seasonal Variability in the Prevalence of DWV Strains in Individual Colonies of European Honeybees in Hawaii. Insects 2024; 15:219. [PMID: 38667349 PMCID: PMC11050578 DOI: 10.3390/insects15040219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 03/19/2024] [Accepted: 03/21/2024] [Indexed: 04/28/2024]
Abstract
The most prevalent viral pathogen of honeybees is Deformed Wing Virus (DWV) and its two most widely studied and common master-variants are DWV-A and DWV-B. The prevalence of DWV variants in the UK and in the US is changing, with the prevalence of the DWV-A strain declining and DWV-B increasing over time. In 2012, only DWV-A was detected on the Hawaiian Islands of Oahu. In this study we focused on a colony-level survey of DWV strains in a single apiary and examined the prevalence of DWV variants over the course of two years. In 2018 and 2019, a total of 16 colonies underwent viral testing in January, May, and September. Of those 16 colonies, four were monitored in both 2018 and 2019. Individual colonies showed variability of DWV master variants throughout the sampling period. DWV-A was consistently detected; however, the detection of DWV-B was variable across time in individual colonies. Ultimately, this study demonstrated a seasonal variation in both viral prevalence and load for DWV-B, providing a perspective on the dynamic nature of DWV master variants emerging in Hawaii.
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Affiliation(s)
- Zhening Zhang
- Department of Plant and Environmental Protection Sciences, College of Tropical Agriculture and Human Resources, University of Hawaii, 3050 Maile Way, 310 Gilmore Hall, Honolulu, HI 96822, USA; (E.M.V.); (S.N.)
| | - Ethel M. Villalobos
- Department of Plant and Environmental Protection Sciences, College of Tropical Agriculture and Human Resources, University of Hawaii, 3050 Maile Way, 310 Gilmore Hall, Honolulu, HI 96822, USA; (E.M.V.); (S.N.)
| | - Scott Nikaido
- Department of Plant and Environmental Protection Sciences, College of Tropical Agriculture and Human Resources, University of Hawaii, 3050 Maile Way, 310 Gilmore Hall, Honolulu, HI 96822, USA; (E.M.V.); (S.N.)
| | - Stephen J. Martin
- School of Environment and Life Sciences, The University of Salford, Manchester M5 4WT, UK;
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Tse D, Privitera L, Norton AC, Gobbo F, Spooner P, Takeuchi T, Martin SJ, Morris RGM. Cell-type-specific optogenetic stimulation of the locus coeruleus induces slow-onset potentiation and enhances everyday memory in rats. Proc Natl Acad Sci U S A 2023; 120:e2307275120. [PMID: 37931094 PMCID: PMC10655220 DOI: 10.1073/pnas.2307275120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 09/12/2023] [Indexed: 11/08/2023] Open
Abstract
Memory formation is typically divided into phases associated with encoding, storage, consolidation, and retrieval. The neural determinants of these phases are thought to differ. This study first investigated the impact of the experience of novelty in rats incurred at a different time, before or after, the precise moment of memory encoding. Memory retention was enhanced. Optogenetic activation of the locus coeruleus mimicked this enhancement induced by novelty, both when given before and after the moment of encoding. Optogenetic activation of the locus coeruleus also induced a slow-onset potentiation of field potentials in area CA1 of the hippocampus evoked by CA3 stimulation. Despite the locus coeruleus being considered a primarily noradrenergic area, both effects of such stimulation were blocked by the dopamine D1/D5 receptor antagonist SCH 23390. These findings substantiate and enrich the evidence implicating the locus coeruleus in cellular aspects of memory consolidation in hippocampus.
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Affiliation(s)
- Dorothy Tse
- Centre for Discovery Brain Sciences, Edinburgh Neuroscience, University of Edinburgh, EdinburghEH8 9JZ, United Kingdom
- Department of Psychology, Edge Hill University, OmskirkL39 4QP, United Kingdom
| | - Lucia Privitera
- Centre for Discovery Brain Sciences, Edinburgh Neuroscience, University of Edinburgh, EdinburghEH8 9JZ, United Kingdom
- School of Systems Medicine, University of Dundee, DundeeDD1 4HN, United Kingdom
- Barts and the London School of Medicine, Institute of Health Sciences Education, Queen Mary University of London Malta Campus, VictoriaVCT 2570, Malta
| | - Anna C. Norton
- Centre for Discovery Brain Sciences, Edinburgh Neuroscience, University of Edinburgh, EdinburghEH8 9JZ, United Kingdom
| | - Francesco Gobbo
- Centre for Discovery Brain Sciences, Edinburgh Neuroscience, University of Edinburgh, EdinburghEH8 9JZ, United Kingdom
| | - Patrick Spooner
- Centre for Discovery Brain Sciences, Edinburgh Neuroscience, University of Edinburgh, EdinburghEH8 9JZ, United Kingdom
| | - Tomonori Takeuchi
- Danish Research Institute of Translational Neuroscience, Nordic-European Molecular Biology Laboratory Partnership for Molecular Medicine, Aarhus University, Aarhus8000, Denmark
- Center for Proteins in Memory, Danish National Research Foundation, Department of Biomedicine, Aarhus University, Aarhus8000, Denmark
| | - Stephen J. Martin
- School of Systems Medicine, University of Dundee, DundeeDD1 4HN, United Kingdom
| | - Richard G. M. Morris
- Centre for Discovery Brain Sciences, Edinburgh Neuroscience, University of Edinburgh, EdinburghEH8 9JZ, United Kingdom
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Stubbendorff C, Hale E, Bast T, Cassaday HJ, Martin SJ, Suwansawang S, Halliday DM, Stevenson CW. Dopamine D1-like receptors modulate synchronized oscillations in the hippocampal-prefrontal-amygdala circuit in contextual fear. Sci Rep 2023; 13:17631. [PMID: 37848657 PMCID: PMC10582086 DOI: 10.1038/s41598-023-44772-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 10/12/2023] [Indexed: 10/19/2023] Open
Abstract
Contextual fear conditioning (CFC) is mediated by a neural circuit that includes the hippocampus, prefrontal cortex, and amygdala, but the neurophysiological mechanisms underlying the regulation of CFC by neuromodulators remain unclear. Dopamine D1-like receptors (D1Rs) in this circuit regulate CFC and local synaptic plasticity, which is facilitated by synchronized oscillations between these areas. In rats, we determined the effects of systemic D1R blockade on CFC and oscillatory synchrony between dorsal hippocampus (DH), prelimbic (PL) cortex, basolateral amygdala (BLA), and ventral hippocampus (VH), which sends hippocampal projections to PL and BLA. D1R blockade altered DH-VH and reduced VH-PL and VH-BLA synchrony during CFC, as inferred from theta and gamma coherence and theta-gamma coupling. D1R blockade also impaired CFC, as indicated by decreased freezing at retrieval, which was characterized by altered DH-VH and reduced VH-PL, VH-BLA, and PL-BLA synchrony. This reduction in VH-PL-BLA synchrony was not fully accounted for by non-specific locomotor effects, as revealed by comparing between epochs of movement and freezing in the controls. These results suggest that D1Rs regulate CFC by modulating synchronized oscillations within the hippocampus-prefrontal-amygdala circuit. They also add to growing evidence indicating that this circuit synchrony at retrieval reflects a neural signature of learned fear.
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Affiliation(s)
- Christine Stubbendorff
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK.
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Via Morego 30, 16163, Genova, Italy.
| | - Ed Hale
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK
- Envigo, Hillcrest, Dodgeford Lane, Belton, LE12 9TE, UK
| | - Tobias Bast
- School of Psychology, University of Nottingham, University Park, Nottingham, UK
- Neuroscience@Nottingham, University of Nottingham, Nottingham, UK
| | - Helen J Cassaday
- School of Psychology, University of Nottingham, University Park, Nottingham, UK
- Neuroscience@Nottingham, University of Nottingham, Nottingham, UK
| | - Stephen J Martin
- Cellular and Systems Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
| | - Sopapun Suwansawang
- School of Physics, Engineering and Technology, York Biomedical Research Institute, University of York, Heslington, York, UK
- Faculty of Science and Technology, Nakhon Pathom Rajabhat University, Nakhon Pathom, Thailand
| | - David M Halliday
- School of Physics, Engineering and Technology, York Biomedical Research Institute, University of York, Heslington, York, UK
| | - Carl W Stevenson
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, LE12 5RD, UK.
- Neuroscience@Nottingham, University of Nottingham, Nottingham, UK.
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Wang R, Fruhauf TF, Sao SS, Gingher EL, Martin SJ, Coleman JS. Clinic-based interventions to increase preexposure prophylaxis awareness and uptake among United States patients attending an obstetrics and gynecology clinic in Baltimore, Maryland. Am J Obstet Gynecol 2023; 229:423.e1-423.e8. [PMID: 37531988 DOI: 10.1016/j.ajog.2023.07.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 07/24/2023] [Accepted: 07/26/2023] [Indexed: 08/04/2023]
Abstract
BACKGROUND Cisgender women account for 1 of every 5 new US HIV diagnoses, with most cases (85%) attributed to heterosexual contact. HIV preexposure prophylaxis is an effective prevention strategy; however, preexposure prophylaxis awareness and prescriptions among women are low. OBJECTIVE This study aimed to increase preexposure prophylaxis counseling and uptake among cisgender women attending obstetrics and gynecology clinics. STUDY DESIGN The study included 3 obstetrics and gynecology clinics within a single health system in a high HIV prevalence region. There were 3 phases: baseline (the 3-month period before the clinical trial that included provider education and training of a registered nurse about preexposure prophylaxis), clinical trial (the 3-month period during which eligible patients were randomized to an active control or preexposure prophylaxis registered nurse intervention), and maintenance (the 3-month period after the trial ended). Electronic medical record clinical decision support tools were available to both arms during the clinical trial, which included best practice alerts, order sets, progress note templates, and written and video preexposure prophylaxis educational materials for patients. In the intervention arm, a preexposure prophylaxis nurse contacted and counseled patients and was equipped to prescribe preexposure prophylaxis. Moreover, this study evaluated the phases through the "reach, effectiveness, adoption, implementation, and maintenance" framework. The primary outcome of the study was effectiveness (eg, percentage of eligible patients with documented HIV prevention counseling in the electronic medical record or preexposure prophylaxis prescriptions). The secondary outcomes included reach (eg, percentage of best practice alerts that providers acted on or the percentage of eligible patients who spoke with the preexposure prophylaxis registered nurse), adoption (eg, percentage of eligible patients with a best practice alert that triggered or the percentage of eligible patients the preexposure prophylaxis registered nurse attempted to contact), and maintenance (eg, percentage of patients with documented HIV prevention counseling or preexposure prophylaxis prescriptions during the maintenance phase). RESULTS There were 904 unique patients in all phases with a mean age of 28.8±7.7 years, and 416 patients (46%) were pregnant; moreover, 436 patients were randomized in the clinical trial phase. Concerning reach and adoption, best practice alerts were triggered for 100% of eligible encounters; however, the providers acted on 52% of them. The preexposure prophylaxis nurse attempted to contact every patient and successfully spoke with 81.2% of them in the preexposure prophylaxis registered nurse arm. Concerning effectiveness, there were significantly more patients counseled about preexposure prophylaxis in the preexposure prophylaxis registered nurse group than in the active control group (66.5% vs 12.3%, respectively; P<.001), although preexposure prophylaxis prescriptions were equivalent (P=1.0). Among the subgroup of patients who were counseled about preexposure prophylaxis, 18.5% of patients in the active control arm and 3.4% in the preexposure prophylaxis registered nurse arm were prescribed preexposure prophylaxis (P=.02). Concerning maintenance, clinical decision support tools alone resulted in preexposure prophylaxis counseling of 1.0% of patients during the maintenance phase vs 0.6% of patients during the baseline phase and 11.2% of patients during the clinical trial phase (P<.001). Preexposure prophylaxis prescriptions were not statistically different among the 3 phases (P=.096). CONCLUSION A preexposure prophylaxis nurse effectively increased HIV prevention discussions but did not lead to more preexposure prophylaxis prescriptions than the preexposure prophylaxis-focused clinical decision support tools used by providers. The decrease in preexposure prophylaxis counseling after the trial phase suggests that persistent interventions are needed to maintain effects.
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Affiliation(s)
- Runzhi Wang
- Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD.
| | - Timothee F Fruhauf
- Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Saumya S Sao
- Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Erin L Gingher
- Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Stephen J Martin
- Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Jenell S Coleman
- Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD
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de Miranda JR, Brettell LE, Chejanovsky N, Childers AK, Dalmon A, Deboutte W, de Graaf DC, Doublet V, Gebremedhn H, Genersch E, Gisder S, Granberg F, Haddad NJ, Kaden R, Manley R, Matthijnssens J, Meeus I, Migdadi H, Milbrath MO, Mondet F, Remnant EJ, Roberts JMK, Ryabov EV, Sela N, Smagghe G, Somanathan H, Wilfert L, Wright ON, Martin SJ, Ball BV. Cold case: The disappearance of Egypt bee virus, a fourth distinct master strain of deformed wing virus linked to honeybee mortality in 1970's Egypt. Virol J 2022; 19:12. [PMID: 35033134 PMCID: PMC8760790 DOI: 10.1186/s12985-022-01740-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [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: 08/04/2021] [Accepted: 12/31/2021] [Indexed: 01/11/2023] Open
Abstract
In 1977, a sample of diseased adult honeybees (Apis mellifera) from Egypt was found to contain large amounts of a previously unknown virus, Egypt bee virus, which was subsequently shown to be serologically related to deformed wing virus (DWV). By sequencing the original isolate, we demonstrate that Egypt bee virus is in fact a fourth unique, major variant of DWV (DWV-D): more closely related to DWV-C than to either DWV-A or DWV-B. DWV-A and DWV-B are the most common DWV variants worldwide due to their close relationship and transmission by Varroa destructor. However, we could not find any trace of DWV-D in several hundred RNA sequencing libraries from a worldwide selection of honeybee, varroa and bumblebee samples. This means that DWV-D has either become extinct, been replaced by other DWV variants better adapted to varroa-mediated transmission, or persists only in a narrow geographic or host range, isolated from common bee and beekeeping trade routes.
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Affiliation(s)
- Joachim R de Miranda
- Department of Ecology, Swedish University of Agricultural Sciences, 750-07, Uppsala, Sweden.
| | - Laura E Brettell
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Renrith, NSW, 2751, Australia.,School of Environment and Life Sciences, University of Salford, Manchester, M5 4WT, UK.,Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Nor Chejanovsky
- Institute of Plant Protection, The Volcani Center, PO Box 15159, 7528809, Rishon Lezion, Israel
| | - Anna K Childers
- Bee Research Laboratory, Beltsville Agricultural Research Center, USDA, Beltsville, MD, 20705, USA
| | - Anne Dalmon
- Abeilles et Environnement, INRAE, 84914, Avignon, France
| | - Ward Deboutte
- Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory for Clinical and Epidemiological Virology, University of Leuven, 3000, Leuven, Belgium.,Max Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, 79108, Freiburg, Germany
| | - Dirk C de Graaf
- Laboratory of Molecular Entomology and Bee Pathology, Ghent University, 9000, Ghent, Belgium
| | - Vincent Doublet
- College of Life and Environmental Sciences, University of Exeter, Penryn, TR10 9FE, UK.,Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Haftom Gebremedhn
- Laboratory of Molecular Entomology and Bee Pathology, Ghent University, 9000, Ghent, Belgium.,Tigray Agricultural Research Institute, P.O. Box 492, Mekelle, Ethiopia
| | - Elke Genersch
- Institut Für Mikrobiologie Und Tierseuchen, Fachbereich Veterinärmedizin, Freie Universität Berlin, Berlin, Germany.,Department of Molecular Microbiology and Bee Diseases, Institute for Bee Research, Hohen Neuendorf, Germany
| | - Sebastian Gisder
- Department of Molecular Microbiology and Bee Diseases, Institute for Bee Research, Hohen Neuendorf, Germany
| | - Fredrik Granberg
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, 750-07, Uppsala, Sweden
| | - Nizar J Haddad
- Bee Research Department, National Agricultural Research Center, Baq'a, Jordan
| | - Rene Kaden
- Department of Ecology, Swedish University of Agricultural Sciences, 750-07, Uppsala, Sweden.,Clinical Microbiology, Department of Medical Sciences, Uppsala University, 753 09, Uppsala, Sweden
| | - Robyn Manley
- College of Life and Environmental Sciences, University of Exeter, Penryn, TR10 9FE, UK
| | - Jelle Matthijnssens
- Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory for Clinical and Epidemiological Virology, University of Leuven, 3000, Leuven, Belgium
| | - Ivan Meeus
- Laboratory of Agrozoology, Department of Plants and Crops, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Hussein Migdadi
- Bee Research Department, National Agricultural Research Center, Baq'a, Jordan
| | - Meghan O Milbrath
- Department of Ecology, Swedish University of Agricultural Sciences, 750-07, Uppsala, Sweden
| | - Fanny Mondet
- Abeilles et Environnement, INRAE, 84914, Avignon, France
| | - Emily J Remnant
- Behaviour, Ecology and Evolution (BEE) Lab, School of Life and Environmental Sciences, The University of Sydney, Camperdown, 2006, Australia
| | - John M K Roberts
- Commonwealth Scientific and Industrial Research Organisation, Canberra, 2601, Australia
| | - Eugene V Ryabov
- Bee Research Laboratory, Beltsville Agricultural Research Center, USDA, Beltsville, MD, 20705, USA
| | - Noa Sela
- Institute of Plant Protection, The Volcani Center, PO Box 15159, 7528809, Rishon Lezion, Israel
| | - Guy Smagghe
- Laboratory of Agrozoology, Department of Plants and Crops, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Hema Somanathan
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, 695551, India
| | - Lena Wilfert
- College of Life and Environmental Sciences, University of Exeter, Penryn, TR10 9FE, UK.,Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Owen N Wright
- Centre for Research in Animal Behaviour, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QG, UK
| | - Stephen J Martin
- School of Environment and Life Sciences, University of Salford, Manchester, M5 4WT, UK.,Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Brenda V Ball
- Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
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Brettell LE, Martin SJ, Riegler M, Cook JM. Vulnerability of island insect pollinator communities to pathogens. J Invertebr Pathol 2021; 186:107670. [PMID: 34560107 DOI: 10.1016/j.jip.2021.107670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/26/2021] [Accepted: 09/14/2021] [Indexed: 10/20/2022]
Abstract
Island ecosystems, which often contain undescribed insects and small populations of single island endemics, are at risk from diverse threats. The spread of pathogens is a major factor affecting not just pollinator species themselves, but also posing significant knock-on effects to often fragile island ecosystems through disruption of pollination networks. Insects are vulnerable to diverse pathogens and these can be introduced to islands in a number of ways, e.g. via the introduction of infected managed pollinator hosts (e.g. honey bees and their viruses, in particular Deformed wing virus), long-range migrants (e.g. monarch butterflies and their protozoan parasite, Ophryocystit elektroscirrha) and invasive species (e.g. social wasps are common invaders and are frequently infected with multi-host viruses such as Kashmir bee virus and Moku virus). Furthermore, these introductions can negatively affect island ecosystems through outcompeting native taxa for resources. As such, the greatest threat to island pollinator communities is not one particular pathogen, but the combination of pathogens and introduced and invasive insects that will likely carry them.
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Affiliation(s)
- Laura E Brettell
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia; Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place L3 5QA, UK.
| | - Stephen J Martin
- School of Environment and life Sciences, University of Salford, Manchester M5 4WT, UK
| | - Markus Riegler
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - James M Cook
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
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8
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Grindrod I, Martin SJ. Parallel evolution of Varroa resistance in honey bees: a common mechanism across continents? Proc Biol Sci 2021; 288:20211375. [PMID: 34344183 PMCID: PMC8334839 DOI: 10.1098/rspb.2021.1375] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 07/12/2021] [Indexed: 12/17/2022] Open
Abstract
The near-globally distributed ecto-parasitic mite of the Apis mellifera honeybee, Varroa destructor, has formed a lethal association with Deformed wing virus, a once rare and benign RNA virus. In concert, the two have killed millions of wild and managed colonies, particularly across the Northern Hemisphere, forcing the need for regular acaricide application to ensure colony survival. However, despite the short association (in evolutionary terms), a small but increasing number of A. mellifera populations across the globe have been surviving many years without any mite control methods. This long-term survival, or Varroa resistance, is consistently associated with the same suite of traits (recapping, brood removal and reduced mite reproduction) irrespective of location. Here we conduct an analysis of data extracted from 60 papers to illustrate how these traits connect together to explain decades of mite resistance data. We have potentially a unified understanding of natural Varroa resistance that will help the global industry achieve widespread miticide-free beekeeping and indicate how different honeybee populations across four continents have resolved a recent threat using the same suite of behaviours.
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Affiliation(s)
- Isobel Grindrod
- School of Environment and Life Sciences, University of Salford, Manchester M5 4WT, UK
| | - Stephen J. Martin
- School of Environment and Life Sciences, University of Salford, Manchester M5 4WT, UK
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9
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Brettell LE, Schroeder DC, Martin SJ. RNAseq of Deformed Wing Virus and Other Honey Bee-Associated Viruses in Eight Insect Taxa with or without Varroa Infestation. Viruses 2020; 12:E1229. [PMID: 33138298 PMCID: PMC7692275 DOI: 10.3390/v12111229] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 10/21/2020] [Accepted: 10/22/2020] [Indexed: 12/12/2022] Open
Abstract
The global spread of a parasitic mite (Varroa destructor) has resulted in Deformed wing virus (DWV), a previously rare pathogen, now dominating the viromes in honey bees and contributing to large-scale honey bee colony losses. DWV can be found in diverse insect taxa and has been implicated in spilling over from honey bees into associated ("apiary") and other ("non-apiary") insects. Here we generated next generation sequence data from 127 insect samples belonging to diverse taxa collected from Hawaiian islands with and without Varroa to identify whether the mite has indirectly affected the viral landscapes of key insect taxa across bees, wasps, flies and ants. Our data showed that, while Varroa was associated with a dramatic increase in abundance of (predominantly recombinant) DWV in honey bees (and no other honey bee-associated RNA virus), this change was not seen in any other taxa sampled. Honey bees share their environment with other insect populations and exist as a homogenous group, frequently sharing common viruses, albeit at low levels. Our data suggest that the threat of Varroa to increase viral load in an apiary does not automatically translate to an increase in virus load in other insects living in the wider community.
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Affiliation(s)
- Laura E. Brettell
- Hawkesbury Institute for the Environment, Western Sydney University, Locked bag 1797, Penrith, NSW 2751, Australia
- School of Environment and life Sciences, University of Salford, Manchester M5 5WT, UK;
| | - Declan C. Schroeder
- Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA;
- School of Biological Sciences, University of Reading, Reading RG6 6LA, UK
| | - Stephen J. Martin
- School of Environment and life Sciences, University of Salford, Manchester M5 5WT, UK;
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10
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Highfield A, Kevill J, Mordecai G, Hunt J, Henderson S, Sauvard D, Feltwell J, Martin SJ, Sumner S, Schroeder DC. Detection and Replication of Moku Virus in Honey Bees and Social Wasps. Viruses 2020; 12:v12060607. [PMID: 32498304 PMCID: PMC7354477 DOI: 10.3390/v12060607] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 05/26/2020] [Accepted: 05/26/2020] [Indexed: 12/12/2022] Open
Abstract
Transmission of honey bee viruses to other insects, and vice versa, has previously been reported and the true ecological importance of this phenomenon is still being realized. Members of the family Vespidae interact with honey bees via predation or through the robbing of brood or honey from colonies, and these activities could result in virus transfer. In this study we screened Vespa velutina and Vespa crabro collected from Europe and China and also honey bees and Vespula vulgaris from the UK for Moku virus (MV), an Iflavirus first discovered in the predatory social wasp Vespula pensylvanica in Hawaii. MV was found in 71% of Vespulavulgaris screened and was also detected in UK Vespa crabro. Only seven percent of Vespa velutina individuals screened were MV-positive and these were exclusively samples from Jersey. Of 69 honey bee colonies screened, 43% tested positive for MV. MV replication was confirmed in Apis mellifera and Vespidae species, being most frequently detected in Vespulavulgaris. MV sequences from the UK were most similar to MV from Vespulapensylvanica compared to MV from Vespa velutina in Belgium. The implications of the transfer of viruses between the Vespidae and honey bees are discussed.
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Affiliation(s)
- Andrea Highfield
- The Marine Biological Association of the United Kingdom, Citadel Hill, Plymouth PL1 2PB, UK; (G.M.); (J.H.); (S.H.)
- Correspondence: (A.H.); (D.C.S.); Tel.: +1-612-413-0030 (D.C.S.)
| | - Jessica Kevill
- School of Environmental and Life Sciences, The University of Salford, Manchester M5 4WT, UK; (J.K.); (S.J.M.)
- Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA
| | - Gideon Mordecai
- The Marine Biological Association of the United Kingdom, Citadel Hill, Plymouth PL1 2PB, UK; (G.M.); (J.H.); (S.H.)
- Department of Medicine, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - Jade Hunt
- The Marine Biological Association of the United Kingdom, Citadel Hill, Plymouth PL1 2PB, UK; (G.M.); (J.H.); (S.H.)
| | - Summer Henderson
- The Marine Biological Association of the United Kingdom, Citadel Hill, Plymouth PL1 2PB, UK; (G.M.); (J.H.); (S.H.)
| | | | - John Feltwell
- Wildlife Matters Consultancy Unit, Battle, East Sussex TN33 9BN, UK;
| | - Stephen J. Martin
- School of Environmental and Life Sciences, The University of Salford, Manchester M5 4WT, UK; (J.K.); (S.J.M.)
| | - Seirian Sumner
- Centre for Biodiversity and Environment Research, University College London, Gower Street, London WC1E 6BT, UK;
| | - Declan C. Schroeder
- The Marine Biological Association of the United Kingdom, Citadel Hill, Plymouth PL1 2PB, UK; (G.M.); (J.H.); (S.H.)
- Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA
- School of Biological Sciences, University of Reading, Reading RG6 6LA, UK
- Correspondence: (A.H.); (D.C.S.); Tel.: +1-612-413-0030 (D.C.S.)
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11
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Harada R, Yoshioka M, Okuyama H, Kato M, Martin SJ, Takahashi JI. Complete mitochondrial DNA sequence of the parasitic honey bee mite Varroa destructor (Mesostigmata: Varroidae). Mitochondrial DNA B Resour 2020; 5:635-636. [PMID: 33366680 PMCID: PMC7748463 DOI: 10.1080/23802359.2019.1711219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Varroa destructor is a parasite mite of the eastern honey bee Apis cerana, which is native to Asia. The European honey bee Apis mellifera was imported to Asia from Europe and the USA for apiculture in the 19th century. In a short period of time, V. destructor parasitized the artificially introduced honey bees. Varroa destructor was estimated to have spread around the world with A. mellifera when it was exported from Asia to locations worldwide about 50 years ago. The mitochondrial DNA of the parasitic honey bee mite V. destructor was analyzed using next-generation sequencing. The complete mitochondrial genome of V. destructor was identified as a 16,476-bp circular molecule containing 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and one AT-rich control region. The heavy strand was predicted to have nine PCGs and 13 tRNA genes, whereas the light strand was predicted to contain four PCGs, nine tRNA genes, and two rRNA genes. All PCGs began with ATA as the start codon, except COIII and CytB, which had ATG as the start codon. Stop codons were of two types: TAA for eight genes and TAG for five genes. Molecular phylogenetic analysis revealed that V. destructor from Japan was genetically distant from that of France. A high base substitution rate of 2.82% was also confirmed between the complete mitochondrial DNA sequences of V. destructor from Japan and the USA, suggesting that one Varroa mite strain found in the USA is not from Japan.
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Affiliation(s)
- Reona Harada
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Masato Yoshioka
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Hisashi Okuyama
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | | | - Stephen J Martin
- School of Environment and Life Sciences, The University of Salford, Manchester, UK
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12
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Abstract
Deformed wing virus (DWV) has become the most well-known, widespread, and intensively studied insect pathogen in the world. Although DWV was previously present in honeybee populations, the arrival and global spread of a new vector, the ectoparasitic mite Varroa destructor, has dramatically altered DWV epidemiology. DWV is now the most prevalent virus in honeybees, with a minimum average of 55% of colonies/apiaries infected across 32 countries. Additionally, DWV has been detected in 65 arthropod species spanning eight insect orders and three orders of Arachnida. Here, we describe the significant progress that has been made in elucidating the capsid structure of the virus, understanding its ever-expanding host range, and tracking the constantly evolving DWV genome and formation of recombinants. The construction of molecular clones, working with DWV in cell lines, and the development of immunohistochemistry methods will all help the community to move forward. Identifying the tissues in which DWV variants are replicating and understanding the impact of DWV in non-honeybee hosts are major new goals.
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Affiliation(s)
- Stephen J Martin
- School of Environment and Life Sciences, University of Salford, Manchester M5 4WT, United Kingdom;
| | - Laura E Brettell
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, New South Wales 2751, Australia;
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13
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Berrell SL, Byard SJ, Carey JS, Codina A, Davis JA, Filer K, Garnett A, Marshall R, Martin SJ, Mykytiuk J, Northen J, Pandya U, Reid G, Smyth C, Watson L. Process Development toward a Pro-Drug of Buprenorphine. Org Process Res Dev 2019. [DOI: 10.1021/acs.oprd.9b00025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - John S. Carey
- Indivior, Henry Boot Way, Priory Park, Hull HU4 7DY, U.K
| | - Antonio Codina
- Aesica Pharmaceuticals Ltd, Windmill Industrial Estate, Shotton Lane, Cramlington, Northumberland NE23 3JL, U.K
| | - J. Alf Davis
- Indivior, Henry Boot Way, Priory Park, Hull HU4 7DY, U.K
| | | | - Alasdair Garnett
- Aesica Pharmaceuticals Ltd, Windmill Industrial Estate, Shotton Lane, Cramlington, Northumberland NE23 3JL, U.K
| | - Robin Marshall
- Aesica Pharmaceuticals Ltd, Windmill Industrial Estate, Shotton Lane, Cramlington, Northumberland NE23 3JL, U.K
| | - Stephen J. Martin
- Aesica Pharmaceuticals Ltd, Windmill Industrial Estate, Shotton Lane, Cramlington, Northumberland NE23 3JL, U.K
| | - John Mykytiuk
- Onyx Scientific Ltd, Silverbriar, Sunderland Enterprise Park East, Sunderland SR5 2TQ, U.K
| | - Julian Northen
- Onyx Scientific Ltd, Silverbriar, Sunderland Enterprise Park East, Sunderland SR5 2TQ, U.K
| | - Urvish Pandya
- Onyx Scientific Ltd, Silverbriar, Sunderland Enterprise Park East, Sunderland SR5 2TQ, U.K
| | - Gary Reid
- Aesica Pharmaceuticals Ltd, Windmill Industrial Estate, Shotton Lane, Cramlington, Northumberland NE23 3JL, U.K
| | - Catherine Smyth
- Aesica Pharmaceuticals Ltd, Windmill Industrial Estate, Shotton Lane, Cramlington, Northumberland NE23 3JL, U.K
| | - Lesa Watson
- Aesica Pharmaceuticals Ltd, Windmill Industrial Estate, Shotton Lane, Cramlington, Northumberland NE23 3JL, U.K
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14
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Takahashi JI, Okuyama H, Martin SJ. Complete mitochondrial DNA sequence of the small hive beetle Aethina tumida (Insecta: Coleoptera) from Hawaii. Mitochondrial DNA B Resour 2019. [DOI: 10.1080/23802359.2019.1601516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Affiliation(s)
| | - Hisashi Okuyama
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Stephen J. Martin
- School of Environment and Life Sciences, The University of Salford, Manchester, UK
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15
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Brettell LE, Schroeder DC, Martin SJ. RNAseq Analysis Reveals Virus Diversity within Hawaiian Apiary Insect Communities. Viruses 2019; 11:v11050397. [PMID: 31035609 PMCID: PMC6563275 DOI: 10.3390/v11050397] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/11/2019] [Accepted: 04/24/2019] [Indexed: 12/26/2022] Open
Abstract
Deformed wing virus (DWV) is the most abundant viral pathogen of honey bees and has been associated with large-scale colony losses. DWV and other bee-associated RNA viruses are generalists capable of infecting diverse hosts. Here, we used RNAseq analysis to test the hypothesis that due to the frequency of interactions, a range of apiary pest species would become infected with DWV and/or other honey bee-associated viruses. We confirmed that DWV-A was the most prevalent virus in the apiary, with genetically similar sequences circulating in the apiary pests, suggesting frequent inter-species transmission. In addition, different proportions of the three DWV master variants as indicated by BLAST analysis and genome coverage plots revealed interesting DWV-species groupings. We also observed that new genomic recombinants were formed by the DWV master variants, which are likely adapted to replicate in different host species. Species groupings also applied when considering other viruses, many of which were widespread in the apiaries. In social wasps, samples were grouped further by site, which potentially also influenced viral load. Thus, the apiary invertebrate community has the potential to act as reservoirs of honey bee-associated viruses, highlighting the importance of considering the wider community in the apiary when considering honey bee health.
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Affiliation(s)
- Laura E Brettell
- Hawkesbury Institute for the Environment, Western Sydney University; Locked bag 1797, Penrith 2751, NSW, Australia.
- School of Environment and life Sciences, University of Salford, Manchester, M5 4WT, UK.
| | - Declan C Schroeder
- School of Biological Sciences, University of Reading, Reading RG6 6LA, UK.
- Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA.
| | - Stephen J Martin
- School of Environment and life Sciences, University of Salford, Manchester, M5 4WT, UK.
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16
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Giles ML, MacPhail A, Bell C, Bradshaw CS, Furner V, Gunathilake M, John M, Krishnaswamy S, Martin SJ, Ooi C, Owen L, Russell D, Street A, Post JJ. The barriers to linkage and retention in care for women living with HIV in an high income setting where they comprise a minority group. AIDS Care 2019; 31:730-736. [PMID: 30754996 DOI: 10.1080/09540121.2019.1576843] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Women comprise a minority population of individuals living with HIV in Australia, and are often poorly represented in research and clinical trials so their needs remain largely unknown. Data suggests that they are diagnosed later than men and start antiretroviral therapy at a lower CD4 cell count. This raises the question whether there are sex specific barriers to linkage and retention in care. This study analyzed 484 surveys received from clinicians collecting demographic, virological, and reproductive health data along with perceived barriers to linkage and retention in care. Most women (67%) were estimated to have been linked into care within 28 days of diagnosis. For women who were not linked into care for more than 28 days, the most commonly reason cited was fear of disclosure to others, followed by fear of disclosure to their partner. The main reasons given for non-retention in care were related to transport, carer responsibilities, financial pressure, health beliefs and concern about stigma or disclosure.
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Affiliation(s)
- M L Giles
- a Department of Infectious Diseases , Alfred Health , Melbourne , Australia.,b Department of Obstetrics and Gynecology , Monash University , Melbourne , Australia
| | - A MacPhail
- a Department of Infectious Diseases , Alfred Health , Melbourne , Australia
| | - C Bell
- c Royal Adelaide Hospital , Adelaide , Australia
| | - C S Bradshaw
- d Melbourne Sexual Health Centre , Melbourne , Australia.,e Central Clinical School , Monash University , Melbourne , Australia
| | - V Furner
- f The Albion Centre , Sydney , Australia
| | - M Gunathilake
- g Sexual Health and Blood Borne Virus Unit, Centre for Disease Control , Northern Territory , Darwin , Australia.,h Kirby Institute , University of New South Wales , Sydney , Australia
| | - M John
- i Department of Immunology , Royal Perth Hospital , Perth , Australia
| | - S Krishnaswamy
- j Alice Springs Hospital , Alice Springs , Australia.,k Monash Infectious Diseases , Monash Health , Melbourne , Australia
| | - S J Martin
- l Canberra Sexual Health Service , Canberra Hospital , Canberra , Australia.,m Australian National University , Canberra , Australia
| | - C Ooi
- n Western Sydney Sexual Health Centre , Sydney , Australia
| | - L Owen
- o Statewide Sexual Health Service , Tasmania , Australia
| | - D Russell
- p Cairns Sexual Health Service , Cairns , Australia
| | - A Street
- q Victorian Infectious Diseases Service , Royal Melbourne Hospital , Melbourne , Australia
| | - J J Post
- f The Albion Centre , Sydney , Australia.,r Department of Infectious Diseases, Prince of Wales Hospital , Sydney , Australia.,s Prince of Wales Clinical School , University of New South Wales , Sydney , Australia
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17
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de Souza FS, Kevill JL, Correia-Oliveira ME, de Carvalho CAL, Martin SJ. Occurrence of deformed wing virus variants in the stingless bee Melipona subnitida and honey bee Apis mellifera populations in Brazil. J Gen Virol 2019; 100:289-294. [PMID: 30628883 DOI: 10.1099/jgv.0.001206] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The global spread of the parasitic Varroa mite has introduced a new bee to the bee horizontal transmission route for several RNA viruses that bypasses existing barriers in honey bees. From among these viruses, deformed wing virus (DWV) is now among the most widespread insect pathogens in the world. Brazilian stingless bees are a diverse group often managed in close proximity to honey bees. Therefore, we investigated the prevalence and load of DWV in 21 stingless bee (Melipona subnitida) and 26 honey bee (Apis mellifera) colonies from Brazil. DWV was detected in all colonies with DWV-A and DWV-C dominating in M. subnitida, while DWV-A dominated in A. mellifera. Average total viral loads per bee were 8.8E+07 and 6.3E+07 in M. subnitida and A. mellifera, respectively, which are much lower than DWV levels (>1E+10) found in honey bees in the northern hemisphere. In colonies introduced 30 years ago to the remote island of Fernando de Noronha, the DWV load was low (<1E+03) in honey bees but we detected higher loads (1.6E+08) in all M. subnitida colonies on the island. This may suggest that minimal, if any, viral transmission of DWV from stingless bees to honey bees has occurred on this island. Furthermore, the ubiquitous presence of the DWV-C variant in M. subnitida colonies, and its rarity in A. mellifera, may again suggest that limited viral exchange between these two species is occurring.
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Affiliation(s)
- Flaviane S de Souza
- 1School of Environment and Life Sciences, The University of Salford, Manchester M5 4WT, UK.,2Federal University of Recôncavo of Bahia, Rui Barbosa 710, 44380-000, Cruz das Almas, Bahia, Brazil
| | - Jessica L Kevill
- 1School of Environment and Life Sciences, The University of Salford, Manchester M5 4WT, UK
| | - Maria E Correia-Oliveira
- 2Federal University of Recôncavo of Bahia, Rui Barbosa 710, 44380-000, Cruz das Almas, Bahia, Brazil
| | - Carlos A L de Carvalho
- 2Federal University of Recôncavo of Bahia, Rui Barbosa 710, 44380-000, Cruz das Almas, Bahia, Brazil
| | - Stephen J Martin
- 1School of Environment and Life Sciences, The University of Salford, Manchester M5 4WT, UK
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18
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Takahashi J, Okuyama H, Kiyoshi T, Takeuchi T, Martin SJ. Origins of Vespa velutina hornets that recently invaded Iki Island, Japan and Jersey Island, UK. Mitochondrial DNA A DNA Mapp Seq Anal 2018; 30:434-439. [PMID: 30489182 DOI: 10.1080/24701394.2018.1538366] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The native distribution of the yellow-legged hornet, Vespa velutina, is throughout East Asia. Around 15 years ago this species was accidentally introduced into South Korea and France, where it became established and then spread into neighbouring countries. Previous mitochondrial DNA studies showed that the South Korean, Japanese, and French populations all originated from Eastern China. Recently, the hornet has invaded Iki Island, Japan and Jersey Island, UK. In this study, we analyze the complete mitochondrial DNA sequence of V. velutina to trace the origin of these two populations. The mitochondrial DNA haplotypes (COI, Cytb, and 16S rRNA) of V. velutina in Iki Island matched the unique haplotype present in China, South Korea, and Japan, while the haplotype from Jersey Island matched that of V. velutina found in France and China. These findings were supported by data from the complete mitochondrial DNA sequence of V. velutina from Iki Island, which was consistent with the sequence from South Korea and Tsushima, whereas V. velutina in Jersey was most similar to the French population.
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Affiliation(s)
- J Takahashi
- a Faculty of Life Sciences , Kyoto Sangyo University , Kyoto , Japan
| | - H Okuyama
- a Faculty of Life Sciences , Kyoto Sangyo University , Kyoto , Japan
| | - T Kiyoshi
- b Department of Zoology , National Museum of Nature and Science , Tsukuba , Japan
| | - T Takeuchi
- a Faculty of Life Sciences , Kyoto Sangyo University , Kyoto , Japan
| | - S J Martin
- c School of Environment and Life Sciences, The University of Salford , Manchester , UK
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20
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Abstract
Mapping the public health threat of tickborne pathogens requires quantification of not only the density of infected host-seeking ticks but also the rate of human exposure to these ticks. To efficiently sample a high number of persons in a short time, we used a mass-participation outdoor event. In June 2014, we sampled ≈500 persons competing in a 2-day mountain marathon run across predominantly tick-infested habitat in Scotland. From the number of tick bites recorded and prevalence of tick infection with Borrelia burgdoferi sensu lato and B. miyamotoi, we quantified the frequency of competitor exposure to the pathogens. Mass-participation outdoor events have the potential to serve as excellent windows for epidemiologic study of tickborne pathogens; their concerted use should improve spatial and temporal mapping of human exposure to infected ticks.
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21
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Martin SJ, Shemilt S, da S Lima CB, de Carvalho CAL. Are Isomeric Alkenes Used in Species Recognition among Neo-Tropical Stingless Bees (Melipona Spp). J Chem Ecol 2017; 43:1066-1072. [PMID: 29147977 PMCID: PMC5735199 DOI: 10.1007/s10886-017-0901-5] [Citation(s) in RCA: 6] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 10/18/2017] [Indexed: 11/12/2022]
Abstract
Our understanding of the role of cuticular hydrocarbons (CHC) in recognition is based largely on temperate ant species and honey bees. The stingless bees remain relatively poorly studied, despite being the largest group of eusocial bees, comprising more than 400 species in some 60 genera. The Meliponini and Apini diverged between 80-130 Myr B.P. so the evolutionary trajectories that shaped the chemical communication systems in ants, honeybees and stingless bees may be very different. The aim of this study was to study if a unique species CHC signal existed in Neotropical stingless bees, as has been shown for many temperate species, and what compounds are involved. This was achieved by collecting CHC data from 24 colonies belonging to six species of Melipona from North-Eastern Brazil and comparing the results with previously published CHC studies on Melipona. We found that each of the eleven Melipona species studied so far each produced a unique species CHC signal based around their alkene isomer production. A remarkable number of alkene isomers, up to 25 in M. asilvai, indicated the diversification of alkene positional isomers among the stingless bees. The only other group to have really diversified in alkene isomer production are the primitively eusocial Bumblebees (Bombus spp), which are the sister group of the stingless bees. Furthermore, among the eleven Neotropical Melipona species we could detect no effect of the environment on the proportion of alkane production as has been suggested for some other species.
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Affiliation(s)
- Stephen J Martin
- School of Environment and Life Sciences, The University of Salford, M5 4WT, Manchester, UK.
| | - Sue Shemilt
- Chemical Ecology Group, School of Physical and Geographical Sciences, Lennard-Jones Laboratory, Keele University, Newcastle upon Tyne, ST5 5BG, UK
| | - Cândida B da S Lima
- School of Environment and Life Sciences, The University of Salford, M5 4WT, Manchester, UK
- Programa de Pós Graduação em Ciências Agrárias, Universidade Federal do Recôncavo da Bahia, Rua Ruí Barbosa, 710 - Centro, Cruz das Almas, BA, 44380-000, Brazil
| | - Carlos A L de Carvalho
- Programa de Pós Graduação em Ciências Agrárias, Universidade Federal do Recôncavo da Bahia, Rua Ruí Barbosa, 710 - Centro, Cruz das Almas, BA, 44380-000, Brazil
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22
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Okuyama H, Martin SJ, Takahashi JI. Complete mitochondrial DNA sequence of the tropical hornet Vespa affinis (Insecta, Hymenoptera). Mitochondrial DNA B Resour 2017; 2:776-777. [PMID: 33473977 PMCID: PMC7800416 DOI: 10.1080/23802359.2017.1398622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Accepted: 10/26/2017] [Indexed: 11/07/2022] Open
Abstract
We analyzed the complete mitochondrial genome of the Asian tropical hornet Vespa affinis from Ishigaki Island, Japan. It consisted of a circular molecule with 19,109 bp, which is larger to other hornet species e.g. V. velutina. We predicted the genome contained 13 protein-coding, 22 tRNA, and two rRNA genes, along with one A + T-rich control region. The repetitive sequences were confirmed at multiple positions in the non-coding genes. The initiation codons ATA was found in one, ATG in seven, and ATT in five genes, while the termination codons TAA and TAG were observed 11 and two genes, respectively. The average AT content of the genome was 78.4%.
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Affiliation(s)
- Hisashi Okuyama
- Department of Life sciences, Kyoto Sangyo University, Kyoto, Japan
| | - Stephen J. Martin
- School of Environment & Life Sciences, University of Salford, Manchester, UK
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23
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Kevill JL, Highfield A, Mordecai GJ, Martin SJ, Schroeder DC. ABC Assay: Method Development and Application to Quantify the Role of Three DWV Master Variants in Overwinter Colony Losses of European Honey Bees. Viruses 2017; 9:v9110314. [PMID: 29077069 PMCID: PMC5707521 DOI: 10.3390/v9110314] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 10/24/2017] [Accepted: 10/25/2017] [Indexed: 02/05/2023] Open
Abstract
Deformed wing virus (DWV) is one of the most prevalent honey bee viral pathogens in the world. Typical of many RNA viruses, DWV is a quasi-species, which is comprised of a large number of different variants, currently consisting of three master variants: Type A, B, and C. Little is known about the impact of each variant or combinations of variants upon the biology of individual hosts. Therefore, we have developed a new set of master variant-specific DWV primers and a set of standards that allow for the quantification of each of the master variants. Competitive reverse transcriptase polymerase chain reaction (RT-PCR) experimental design confirms that each new DWV primer set is specific to the retrospective master variant. The sensitivity of the ABC assay is dependent on whether DNA or RNA is used as the template and whether other master variants are present in the sample. Comparison of the overall proportions of each master variant within a sample of known diversity, as confirmed by next-generation sequence (NGS) data, validates the efficiency of the ABC assay. The ABC assay was used on archived material from a Devon overwintering colony loss (OCL) 2006-2007 study; further implicating DWV type A and, for the first time, possibly C in the untimely collapse of honey bee colonies. Moreover, in this study DWV type B was not associated with OCL. The use of the ABC assay will allow researchers to quickly and cost effectively pre-screen for the presence of DWV master variants in honey bees.
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Affiliation(s)
- Jessica L Kevill
- School of Environment and Life Sciences, The University of Salford, Manchester M5 4WT, UK.
| | - Andrea Highfield
- Viral Ecology, Marine Biological Association, Plymouth PL1 2PB, UK.
| | - Gideon J Mordecai
- Viral Ecology, Marine Biological Association, Plymouth PL1 2PB, UK.
- Department of Earth, Ocean and Atmospheric Sciences and Biodiversity Research Centre, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
| | - Stephen J Martin
- School of Environment and Life Sciences, The University of Salford, Manchester M5 4WT, UK.
| | - Declan C Schroeder
- Viral Ecology, Marine Biological Association, Plymouth PL1 2PB, UK.
- School of Biological Sciences, University of Reading, Reading RG6 6LA, UK.
- Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA.
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Benaets K, Van Geystelen A, Cardoen D, De Smet L, de Graaf DC, Schoofs L, Larmuseau MHD, Brettell LE, Martin SJ, Wenseleers T. Covert deformed wing virus infections have long-term deleterious effects on honeybee foraging and survival. Proc Biol Sci 2017; 284:20162149. [PMID: 28148747 PMCID: PMC5310602 DOI: 10.1098/rspb.2016.2149] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [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: 10/17/2016] [Accepted: 01/06/2017] [Indexed: 12/27/2022] Open
Abstract
Several studies have suggested that covert stressors can contribute to bee colony declines. Here we provide a novel case study and show using radiofrequency identification tracking technology that covert deformed wing virus (DWV) infections in adult honeybee workers seriously impact long-term foraging and survival under natural foraging conditions. In particular, our experiments show that adult workers injected with low doses of DWV experienced increased mortality rates, that DWV caused workers to start foraging at a premature age, and that the virus reduced the workers' total activity span as foragers. Altogether, these results demonstrate that covert DWV infections have strongly deleterious effects on honeybee foraging and survival. These results are consistent with previous studies that suggested DWV to be an important contributor to the ongoing bee declines in Europe and the USA. Overall, our study underlines the strong impact that covert pathogen infections can have on individual and group-level performance in bees.
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Affiliation(s)
- Kristof Benaets
- Department of Biology, KU Leuven, Laboratory of Socio-ecology and Social Evolution, Leuven, Belgium
| | - Anneleen Van Geystelen
- Department of Biology, KU Leuven, Laboratory of Socio-ecology and Social Evolution, Leuven, Belgium
| | - Dries Cardoen
- Department of Biology, KU Leuven, Laboratory of Socio-ecology and Social Evolution, Leuven, Belgium
| | - Lina De Smet
- Department of Biochemistry and Microbiology, UGent, Laboratory of Molecular Entomology and Bee Pathology, Gent, Belgium
| | - Dirk C de Graaf
- Department of Biochemistry and Microbiology, UGent, Laboratory of Molecular Entomology and Bee Pathology, Gent, Belgium
| | - Liliane Schoofs
- Department of Biology, KU Leuven, Research group of Functional Genomics and Proteomics, Leuven, Belgium
| | - Maarten H D Larmuseau
- Department of Biology, KU Leuven, Laboratory of Socio-ecology and Social Evolution, Leuven, Belgium
- Laboratory of Forensic Genetics and Molecular Archaeology, UZ Leuven, Leuven, Belgium
- Department of Imaging and Pathology, KU Leuven, Forensic Medicine, Leuven, Belgium
| | - Laura E Brettell
- School of Environment and Life Sciences, The University of Salford, Manchester, UK
| | - Stephen J Martin
- School of Environment and Life Sciences, The University of Salford, Manchester, UK
| | - Tom Wenseleers
- Department of Biology, KU Leuven, Laboratory of Socio-ecology and Social Evolution, Leuven, Belgium
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25
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Guillem RM, Drijfhout FP, Martin SJ. Species-Specific Cuticular Hydrocarbon Stability within European Myrmica Ants. J Chem Ecol 2016; 42:1052-1062. [PMID: 27832346 PMCID: PMC5119849 DOI: 10.1007/s10886-016-0784-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [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: 12/01/2015] [Revised: 05/15/2016] [Accepted: 07/04/2016] [Indexed: 01/14/2023]
Abstract
Recognition is a fundamental process on which all subsequent behaviors are based at every organizational level, from the gene up to the super-organism. At the whole organism level, visual recognition is the best understood. However, chemical communication is far more widespread than visual communication, but despite its importance is much less understood. Ants provide an excellent model system for chemical ecology studies as it is well established that compounds known as cuticular hydrocarbons (CHCs) are used as recognition cues in ants. Therefore, stable species-specific odors should exist, irrespective of geographic locality. We tested this hypothesis by comparing the CHC profiles of workers of twelve species of Myrmica ants from four countries across Europe, from Iberia to the Balkans and from the Mediterranean to Fennoscandia. CHCs remained qualitatively stable within each species, right down to the isomer level. Despite the morphological similarity that occurs within the genus Myrmica, their CHCs were highly diverse but remarkably species-specific and stable across wide geographical areas. This indicates a genetic mechanism under strong selection that produces these species-specific chemical profiles, despite each species encountering different environmental conditions across its range.
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Affiliation(s)
- Rhian M Guillem
- Department of Animal and Plant Sciences, University of Sheffield, S10 2TN, Sheffield, UK. .,Department of Earth & Life Sciences, Gibraltar Botanic Gardens Campus, University of Gibraltar, Gibraltar, GX11 1AA, Gibraltar.
| | - Falko P Drijfhout
- Chemical Ecology Group, School of Physical and Geographical Sciences, Lennard-Jones Laboratory, Keele University, Keele, ST5 5BG, UK
| | - Stephen J Martin
- School of Environment & Life Sciences, University of Salford, Manchester, M5 4WT, UK
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Mordecai GJ, Brettell LE, Pachori P, Villalobos EM, Martin SJ, Jones IM, Schroeder DC. Moku virus; a new Iflavirus found in wasps, honey bees and Varroa. Sci Rep 2016; 6:34983. [PMID: 27713534 PMCID: PMC5054524 DOI: 10.1038/srep34983] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 09/21/2016] [Indexed: 11/24/2022] Open
Abstract
There is an increasing global trend of emerging infectious diseases (EIDs) affecting a wide range of species, including honey bees. The global epidemic of the single stranded RNA Deformed wing virus (DWV), driven by the spread of Varroa destructor has been well documented. However, DWV is just one of many insect RNA viruses which infect a wide range of hosts. Here we report the full genome sequence of a novel Iflavirus named Moku virus (MV), discovered in the social wasp Vespula pensylvanica collected in Hawaii. The novel genome is 10,056 nucleotides long and encodes a polyprotein of 3050 amino acids. Phylogenetic analysis showed that MV is most closely related to Slow bee paralysis virus (SBPV), which is highly virulent in honey bees but rarely detected. Worryingly, MV sequences were also detected in honey bees and Varroa from the same location, suggesting that MV can also infect other hymenopteran and Acari hosts.
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Affiliation(s)
- Gideon J Mordecai
- Viral Ecology, Marine Biological Association, Plymouth PL7 5BU, UK
- School of Biological Sciences, University of Reading, Reading RG6 6AJ, UK
| | - Laura E Brettell
- School of Environment and Life Sciences, University of Salford, Manchester M5 4WT, UK
| | - Purnima Pachori
- The Genome Analysis Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Ethel M. Villalobos
- Department of Plant and Environmental Protection Sciences, University of Hawaii, Manoa, HI 96822, USA
| | - Stephen J Martin
- School of Environment and Life Sciences, University of Salford, Manchester M5 4WT, UK
| | - Ian M Jones
- School of Biological Sciences, University of Reading, Reading RG6 6AJ, UK
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Abstract
Ethambutol is commonly used for the treatment of tuberculous and atypical mycobacterial infection. Central nervous system (CNS) toxicity other than optic neuropathy is not widely reported. A 40-year-old man with advanced HIV infection and Mycobacterium avium complex infection experienced rapid cognitive decline after commencement of ethambutol, and symptoms fully resolved with cessation.
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Affiliation(s)
- S J Martin
- Canberra Sexual Health Centre, The Canberra Hospital, Canberra, ACT, Australia.
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Mordecai GJ, Wilfert L, Martin SJ, Jones IM, Schroeder DC. Diversity in a honey bee pathogen: first report of a third master variant of the Deformed Wing Virus quasispecies. ISME J 2016; 10:1264-73. [PMID: 26574686 PMCID: PMC5029213 DOI: 10.1038/ismej.2015.178] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 08/14/2015] [Accepted: 08/21/2015] [Indexed: 01/06/2023]
Abstract
Treatment of emerging RNA viruses is hampered by the high mutation and replication rates that enable these viruses to operate as a quasispecies. Declining honey bee populations have been attributed to the ectoparasitic mite Varroa destructor and its affiliation with Deformed Wing Virus (DWV). In the current study we use next-generation sequencing to investigate the DWV quasispecies in an apiary known to suffer from overwintering colony losses. We show that the DWV species complex is made up of three master variants. Our results indicate that a new DWV Type C variant is distinct from the previously described types A and B, but together they form a distinct clade compared with other members of the Iflaviridae. The molecular clock estimation predicts that Type C diverged from the other variants ∼319 years ago. The discovery of a new master variant of DWV has important implications for the positive identification of the true pathogen within global honey bee populations.
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Affiliation(s)
- Gideon J Mordecai
- Viral Ecology, Marine Biological Association, Plymouth, UK
- School of Biological Sciences, University of Reading, Reading, UK
| | - Lena Wilfert
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, UK
| | - Stephen J Martin
- School of Environment and Life Sciences, The University of Salford, Manchester, UK
| | - Ian M Jones
- School of Biological Sciences, University of Reading, Reading, UK
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Mordecai GJ, Brettell LE, Martin SJ, Dixon D, Jones IM, Schroeder DC. Superinfection exclusion and the long-term survival of honey bees in Varroa-infested colonies. ISME J 2015; 10:1182-91. [PMID: 26505829 PMCID: PMC5029227 DOI: 10.1038/ismej.2015.186] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 08/25/2015] [Accepted: 09/11/2015] [Indexed: 12/20/2022]
Abstract
Over the past 50 years, many millions of European honey bee (Apis mellifera) colonies have died as the ectoparasitic mite, Varroa destructor, has spread around the world. Subsequent studies have indicated that the mite's association with a group of RNA viral pathogens (Deformed Wing Virus, DWV) correlates with colony death. Here, we propose a phenomenon known as superinfection exclusion that provides an explanation of how certain A. mellifera populations have survived, despite Varroa infestation and high DWV loads. Next-generation sequencing has shown that a non-lethal DWV variant 'type B' has become established in these colonies and that the lethal 'type A' DWV variant fails to persist in the bee population. We propose that this novel stable host-pathogen relationship prevents the accumulation of lethal variants, suggesting that this interaction could be exploited for the development of an effective treatment that minimises colony losses in the future.
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Affiliation(s)
- Gideon J Mordecai
- Viral Ecology, Marine Biological Association, Plymouth, UK.,School of Biological Sciences, University of Reading, Reading, UK
| | - Laura E Brettell
- School of Environment and Life Sciences, The University of Salford, Manchester, UK
| | - Stephen J Martin
- School of Environment and Life Sciences, The University of Salford, Manchester, UK
| | - David Dixon
- Viral Ecology, Marine Biological Association, Plymouth, UK
| | - Ian M Jones
- School of Biological Sciences, University of Reading, Reading, UK
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Pradella D, Martin SJ, Dani FR. Using Errors by Guard Honeybees (Apis mellifera) to Gain New Insights into Nestmate Recognition Signals. Chem Senses 2015; 40:649-53. [DOI: 10.1093/chemse/bjv053] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Boden DG, Agarwal A, Hussain T, Martin SJ, Radford N, Riyat MS, So K, Su Y, Turvey A, Whale CI. Lowering levels of bed occupancy is associated with decreased inhospital mortality and improved performance on the 4-hour target in a UK District General Hospital. Emerg Med J 2015; 33:85-90. [PMID: 26380995 DOI: 10.1136/emermed-2014-204479] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 07/23/2015] [Indexed: 01/24/2023]
Abstract
OBJECTIVE To evaluate whether there is an association between an intervention to reduce medical bed occupancy and performance on the 4-hour target and hospital mortality. METHODS This before-and-after study was undertaken in a large UK District General Hospital over a 32 month period. A range of interventions were undertaken to reduce medical bed occupancy within the Trust. Performance on the 4-hour target and hospital mortality (hospital standardised mortality ratio (HSMR), summary hospital-level mortality indicator (SHMI) and crude mortality) were compared before, and after, intervention. Daily data on medical bed occupancy and percentage of patients meeting the 4-hour target was collected from hospital records. Segmented regression analysis of interrupted time-series method was used to estimate the changes in levels and trends in average medical bed occupancy, monthly performance on the target and monthly mortality measures (HSMR, SHMI and crude mortality) that followed the intervention. RESULTS Mean medical bed occupancy decreased significantly from 93.7% to 90.2% (p=0.02). The trend change in target performance, when comparing preintervention and postintervention, revealed a significant improvement (p=0.019). The intervention was associated with a mean reduction in all markers of mortality (range 4.5-4.8%). SHMI (p=0.02) and crude mortality (p=0.018) showed significant trend changes after intervention. CONCLUSIONS Lowering medical bed occupancy is associated with reduced patient mortality and improved ability of the acute Trust to achieve the 95% 4-hour target. Whole system transformation is required to create lower average medical bed occupancy.
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Affiliation(s)
- D G Boden
- Emergency Department, Royal Derby Hospital, Derby, UK
| | - A Agarwal
- Division of Medicine, Royal Derby Hospital, Derby, UK
| | - T Hussain
- Division of Medicine, Royal Derby Hospital, Derby, UK
| | - S J Martin
- Division of Medicine, Royal Derby Hospital, Derby, UK
| | - N Radford
- Department of Operations, Royal Derby Hospital, Derby, UK
| | - M S Riyat
- Emergency Department, Royal Derby Hospital, Derby, UK
| | - K So
- Emergency Department, Royal Derby Hospital, Derby, UK
| | - Y Su
- Dr Su Statistics, Consulting firm, Kaunakakai, Hawaii, USA
| | - A Turvey
- Information Services, RDH, Derby, UK
| | - C I Whale
- Division of Medicine, Royal Derby Hospital, Derby, UK
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Todkill M, Tyson A, Habel P, Moss P, Rossteuscher K, Didlick J, Crawford S, Freeman H, Martin SJ. P13.08 Act testing month: promoting testing and increasing cross sector collaboration. Br J Vener Dis 2015. [DOI: 10.1136/sextrans-2015-052270.506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Lambert M, Currie MJ, Del Rosario R, Tyson A, Martin SJ. P08.32 The feasibility and acceptability of offering opportunistic chlamydia screening in a nurse-led primary health care clinic. Br J Vener Dis 2015. [DOI: 10.1136/sextrans-2015-052270.378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Kather R, Drijfhout FP, Martin SJ. Evidence for colony-specific differences in chemical mimicry in the parasitic mite Varroa destructor. CHEMOECOLOGY 2015. [DOI: 10.1007/s00049-015-0191-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Danso-Boateng E, Shama G, Wheatley AD, Martin SJ, Holdich RG. Hydrothermal carbonisation of sewage sludge: effect of process conditions on product characteristics and methane production. Bioresour Technol 2015; 177:318-327. [PMID: 25496954 DOI: 10.1016/j.biortech.2014.11.096] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 11/20/2014] [Accepted: 11/23/2014] [Indexed: 06/04/2023]
Abstract
Hydrothermal carbonisation of primary sewage sludge was carried out using a batch reactor. The effect of temperature and reaction time on the characteristics of solid (hydrochar), liquid and gas products, and the conditions leading to optimal hydrochar characteristics were investigated. The amount of carbon retained in hydrochars decreased as temperature and time increased with carbon retentions of 64-77% at 140 and 160°C, and 50-62% at 180 and 200°C. Increasing temperature and treatment time increased the energy content of the hydrochar from 17 to 19 MJ/kg but reduced its energy yield from 88% to 68%. Maillard reaction products were identified in the liquid fractions following carbonisations at 180 and 200°C. Theoretical estimates of the methane yields resulting from the anaerobic digestion of the liquid by-products are also presented and optimal reaction conditions to maximise these identified.
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Affiliation(s)
- E Danso-Boateng
- Department of Chemical Engineering, Loughborough University, Loughborough LE11 3TU, UK.
| | - G Shama
- Department of Chemical Engineering, Loughborough University, Loughborough LE11 3TU, UK
| | - A D Wheatley
- School of Civil and Building Engineering, Loughborough University, Loughborough LE11 3TU, UK
| | - S J Martin
- Department of Materials, Loughborough University, Loughborough LE11 3TU, UK
| | - R G Holdich
- Department of Chemical Engineering, Loughborough University, Loughborough LE11 3TU, UK
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37
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Kather R, Drijfhout FP, Shemilt S, Martin SJ. Evidence for passive chemical camouflage in the parasitic mite Varroa destructor. J Chem Ecol 2015; 41:178-86. [PMID: 25620373 DOI: 10.1007/s10886-015-0548-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [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: 10/01/2014] [Revised: 12/01/2014] [Accepted: 01/09/2015] [Indexed: 11/26/2022]
Abstract
Social insect colonies provide a stable and safe environment for their members. Despite colonies being heavily guarded, parasites have evolved numerous strategies to invade and inhabit these hostile places. Two such strategies are (true) chemical mimicry via biosynthesis of host odor, and chemical camouflage, in which compounds are acquired from the host. The ectoparasitic mite Varroa destructor feeds on hemolymph of its honey bee host, Apis mellifera. The mite's odor closely resembles that of its host, which allows V. destructor to remain undetected as it lives on the adult host during its phoretic phase and while reproducing on the honeybee brood. During the mite life cycle, it switches between host adults and brood, which requires it to adjust its profile to mimic the very different odors of honey bee brood and adults. In a series of transfer experiments, using bee adults and pupae, we tested whether V. destructor changes its profile by synthesizing compounds or by using chemical camouflage. We show that V. destructor required direct access to host cuticle to mimic its odor, and that it was unable to synthesize host-specific compounds itself. The mite was able to mimic host odor, even when dead, indicating a passive physico-chemical mechanism of the parasite cuticle. The chemical profile of V. destructor was adjusted within 3 to 9 h after switching hosts, demonstrating that passive camouflage is a highly efficient, fast and flexible way for the mite to adapt to a new host profile when moving between different host life stages or colonies.
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Affiliation(s)
- Ricarda Kather
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
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Galluzzi L, Bravo-San Pedro JM, Vitale I, Aaronson SA, Abrams JM, Adam D, Alnemri ES, Altucci L, Andrews D, Annicchiarico-Petruzzelli M, Baehrecke EH, Bazan NG, Bertrand MJ, Bianchi K, Blagosklonny MV, Blomgren K, Borner C, Bredesen DE, Brenner C, Campanella M, Candi E, Cecconi F, Chan FK, Chandel NS, Cheng EH, Chipuk JE, Cidlowski JA, Ciechanover A, Dawson TM, Dawson VL, De Laurenzi V, De Maria R, Debatin KM, Di Daniele N, Dixit VM, Dynlacht BD, El-Deiry WS, Fimia GM, Flavell RA, Fulda S, Garrido C, Gougeon ML, Green DR, Gronemeyer H, Hajnoczky G, Hardwick JM, Hengartner MO, Ichijo H, Joseph B, Jost PJ, Kaufmann T, Kepp O, Klionsky DJ, Knight RA, Kumar S, Lemasters JJ, Levine B, Linkermann A, Lipton SA, Lockshin RA, López-Otín C, Lugli E, Madeo F, Malorni W, Marine JC, Martin SJ, Martinou JC, Medema JP, Meier P, Melino S, Mizushima N, Moll U, Muñoz-Pinedo C, Nuñez G, Oberst A, Panaretakis T, Penninger JM, Peter ME, Piacentini M, Pinton P, Prehn JH, Puthalakath H, Rabinovich GA, Ravichandran KS, Rizzuto R, Rodrigues CM, Rubinsztein DC, Rudel T, Shi Y, Simon HU, Stockwell BR, Szabadkai G, Tait SW, Tang HL, Tavernarakis N, Tsujimoto Y, Vanden Berghe T, Vandenabeele P, Villunger A, Wagner EF, Walczak H, White E, Wood WG, Yuan J, Zakeri Z, Zhivotovsky B, Melino G, Kroemer G. Essential versus accessory aspects of cell death: recommendations of the NCCD 2015. Cell Death Differ 2014; 22:58-73. [PMID: 25236395 PMCID: PMC4262782 DOI: 10.1038/cdd.2014.137] [Citation(s) in RCA: 664] [Impact Index Per Article: 66.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 07/30/2014] [Indexed: 02/07/2023] Open
Abstract
Cells exposed to extreme physicochemical or mechanical stimuli die in an uncontrollable manner, as a result of their immediate structural breakdown. Such an unavoidable variant of cellular demise is generally referred to as ‘accidental cell death' (ACD). In most settings, however, cell death is initiated by a genetically encoded apparatus, correlating with the fact that its course can be altered by pharmacologic or genetic interventions. ‘Regulated cell death' (RCD) can occur as part of physiologic programs or can be activated once adaptive responses to perturbations of the extracellular or intracellular microenvironment fail. The biochemical phenomena that accompany RCD may be harnessed to classify it into a few subtypes, which often (but not always) exhibit stereotyped morphologic features. Nonetheless, efficiently inhibiting the processes that are commonly thought to cause RCD, such as the activation of executioner caspases in the course of apoptosis, does not exert true cytoprotective effects in the mammalian system, but simply alters the kinetics of cellular demise as it shifts its morphologic and biochemical correlates. Conversely, bona fide cytoprotection can be achieved by inhibiting the transduction of lethal signals in the early phases of the process, when adaptive responses are still operational. Thus, the mechanisms that truly execute RCD may be less understood, less inhibitable and perhaps more homogeneous than previously thought. Here, the Nomenclature Committee on Cell Death formulates a set of recommendations to help scientists and researchers to discriminate between essential and accessory aspects of cell death.
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Affiliation(s)
- L Galluzzi
- 1] Gustave Roussy Cancer Center, Villejuif, France [2] Equipe 11 labellisée par la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France [3] Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France
| | - J M Bravo-San Pedro
- 1] Gustave Roussy Cancer Center, Villejuif, France [2] Equipe 11 labellisée par la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France [3] INSERM, U1138, Gustave Roussy, Paris, France
| | - I Vitale
- Regina Elena National Cancer Institute, Rome, Italy
| | - S A Aaronson
- Department of Oncological Sciences, The Tisch Cancer Institute, Ichan School of Medicine at Mount Sinai, New York, NY, USA
| | - J M Abrams
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - D Adam
- Institute of Immunology, Christian-Albrechts University, Kiel, Germany
| | - E S Alnemri
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - L Altucci
- Dipartimento di Biochimica, Biofisica e Patologia Generale, Seconda Università degli Studi di Napoli, Napoli, Italy
| | - D Andrews
- Department of Biochemistry and Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - M Annicchiarico-Petruzzelli
- Biochemistry Laboratory, Istituto Dermopatico dell'Immacolata - Istituto Ricovero Cura Carattere Scientifico (IDI-IRCCS), Rome, Italy
| | - E H Baehrecke
- Department of Cancer Biology, University of Massachusetts Medical School, Worcester, MA, USA
| | - N G Bazan
- Neuroscience Center of Excellence, School of Medicine, New Orleans, LA, USA
| | - M J Bertrand
- 1] VIB Inflammation Research Center, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - K Bianchi
- 1] Barts Cancer Institute, Cancer Research UK Centre of Excellence, London, UK [2] Queen Mary University of London, John Vane Science Centre, London, UK
| | - M V Blagosklonny
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - K Blomgren
- Karolinska University Hospital, Karolinska Institute, Stockholm, Sweden
| | - C Borner
- Institute of Molecular Medicine and Spemann Graduate School of Biology and Medicine, Albert-Ludwigs University, Freiburg, Germany
| | - D E Bredesen
- 1] Buck Institute for Research on Aging, Novato, CA, USA [2] Department of Neurology, University of California, San Francisco (UCSF), San Francisco, CA, USA
| | - C Brenner
- 1] INSERM, UMRS769, Châtenay Malabry, France [2] LabEx LERMIT, Châtenay Malabry, France [3] Université Paris Sud/Paris XI, Orsay, France
| | - M Campanella
- Department of Comparative Biomedical Sciences and Consortium for Mitochondrial Research, University College London (UCL), London, UK
| | - E Candi
- Department of Experimental Medicine and Surgery, University of Rome Tor Vergata, Rome, Italy
| | - F Cecconi
- 1] Laboratory of Molecular Neuroembryology, IRCCS Fondazione Santa Lucia, Rome, Italy [2] Department of Biology, University of Rome Tor Vergata; Rome, Italy [3] Unit of Cell Stress and Survival, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - F K Chan
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA, USA
| | - N S Chandel
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - E H Cheng
- Human Oncology and Pathogenesis Program and Department of Pathology, Memorial Sloan Kettering Cancer Center (MSKCC), New York, NY, USA
| | - J E Chipuk
- Department of Oncological Sciences, The Tisch Cancer Institute, Ichan School of Medicine at Mount Sinai, New York, NY, USA
| | - J A Cidlowski
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences (NIEHS), National Institute of Health (NIH), North Carolina, NC, USA
| | - A Ciechanover
- Tumor and Vascular Biology Research Center, The Rappaport Faculty of Medicine and Research Institute, Technion Israel Institute of Technology, Haifa, Israel
| | - T M Dawson
- 1] Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering (ICE), Departments of Neurology, Pharmacology and Molecular Sciences, Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA [2] Adrienne Helis Malvin Medical Research Foundation, New Orleans, LA, USA
| | - V L Dawson
- 1] Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering (ICE), Departments of Neurology, Pharmacology and Molecular Sciences, Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA [2] Adrienne Helis Malvin Medical Research Foundation, New Orleans, LA, USA
| | - V De Laurenzi
- Department of Experimental and Clinical Sciences, Gabriele d'Annunzio University, Chieti, Italy
| | - R De Maria
- Regina Elena National Cancer Institute, Rome, Italy
| | - K-M Debatin
- Department of Pediatrics and Adolescent Medicine, Ulm University Medical Center, Ulm, Germany
| | - N Di Daniele
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - V M Dixit
- Department of Physiological Chemistry, Genentech, South San Francisco, CA, USA
| | - B D Dynlacht
- Department of Pathology and Cancer Institute, Smilow Research Center, New York University School of Medicine, New York, NY, USA
| | - W S El-Deiry
- Laboratory of Translational Oncology and Experimental Cancer Therapeutics, Department of Medicine (Hematology/Oncology), Penn State Hershey Cancer Institute, Penn State College of Medicine, Hershey, PA, USA
| | - G M Fimia
- 1] Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Lecce, Italy [2] Department of Epidemiology and Preclinical Research, National Institute for Infectious Diseases Lazzaro Spallanzani, Istituto Ricovero Cura Carattere Scientifico (IRCCS), Rome, Italy
| | - R A Flavell
- Department of Immunobiology, Yale School of Medicine, New Haven, CT, USA
| | - S Fulda
- Institute for Experimental Cancer Research in Pediatrics, Goethe University, Frankfurt, Germany
| | - C Garrido
- 1] INSERM, U866, Dijon, France [2] Faculty of Medicine, University of Burgundy, Dijon, France
| | - M-L Gougeon
- Antiviral Immunity, Biotherapy and Vaccine Unit, Infection and Epidemiology Department, Institut Pasteur, Paris, France
| | - D R Green
- Department of Immunology, St Jude's Children's Research Hospital, Memphis, TN, USA
| | - H Gronemeyer
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
| | - G Hajnoczky
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - J M Hardwick
- W Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University, Baltimore, MD, USA
| | - M O Hengartner
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - H Ichijo
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - B Joseph
- Department of Oncology-Pathology, Cancer Centrum Karolinska (CCK), Karolinska Institute, Stockholm, Sweden
| | - P J Jost
- Medical Department for Hematology, Technical University of Munich, Munich, Germany
| | - T Kaufmann
- Institute of Pharmacology, Medical Faculty, University of Bern, Bern, Switzerland
| | - O Kepp
- 1] Equipe 11 labellisée par la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France [2] INSERM, U1138, Gustave Roussy, Paris, France [3] Metabolomics and Cell Biology Platforms, Gustave Roussy Cancer Center, Villejuif, France
| | - D J Klionsky
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - R A Knight
- 1] Medical Molecular Biology Unit, Institute of Child Health, University College London (UCL), London, UK [2] Medical Research Council Toxicology Unit, Leicester, UK
| | - S Kumar
- 1] Centre for Cancer Biology, University of South Australia, Adelaide, SA, Australia [2] School of Medicine and School of Molecular and Biomedical Science, University of Adelaide, Adelaide, SA, Australia
| | - J J Lemasters
- Departments of Drug Discovery and Biomedical Sciences and Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, USA
| | - B Levine
- 1] Center for Autophagy Research, University of Texas, Southwestern Medical Center, Dallas, TX, USA [2] Howard Hughes Medical Institute (HHMI), Chevy Chase, MD, USA
| | - A Linkermann
- Division of Nephrology and Hypertension, Christian-Albrechts University, Kiel, Germany
| | - S A Lipton
- 1] The Scripps Research Institute, La Jolla, CA, USA [2] Sanford-Burnham Center for Neuroscience, Aging, and Stem Cell Research, La Jolla, CA, USA [3] Salk Institute for Biological Studies, La Jolla, CA, USA [4] University of California, San Diego (UCSD), San Diego, CA, USA
| | - R A Lockshin
- Department of Biological Sciences, St. John's University, Queens, NY, USA
| | - C López-Otín
- Department of Biochemistry and Molecular Biology, Faculty of Medecine, Instituto Universitario de Oncología (IUOPA), University of Oviedo, Oviedo, Spain
| | - E Lugli
- Unit of Clinical and Experimental Immunology, Humanitas Clinical and Research Center, Milan, Italy
| | - F Madeo
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - W Malorni
- 1] Department of Therapeutic Research and Medicine Evaluation, Istituto Superiore di Sanita (ISS), Roma, Italy [2] San Raffaele Institute, Sulmona, Italy
| | - J-C Marine
- 1] Laboratory for Molecular Cancer Biology, Center for the Biology of Disease, Leuven, Belgium [2] Laboratory for Molecular Cancer Biology, Center of Human Genetics, Leuven, Belgium
| | - S J Martin
- Department of Genetics, The Smurfit Institute, Trinity College, Dublin, Ireland
| | - J-C Martinou
- Department of Cell Biology, University of Geneva, Geneva, Switzerland
| | - J P Medema
- Laboratory for Experiments Oncology and Radiobiology (LEXOR), Academic Medical Center (AMC), Amsterdam, The Netherlands
| | - P Meier
- Institute of Cancer Research, The Breakthrough Toby Robins Breast Cancer Research Centre, London, UK
| | - S Melino
- Department of Chemical Sciences and Technologies, University of Rome Tor Vergata, Rome, Italy
| | - N Mizushima
- Graduate School and Faculty of Medicine, University of Tokyo, Tokyo, Japan
| | - U Moll
- Department of Pathology, Stony Brook University, Stony Brook, NY, USA
| | - C Muñoz-Pinedo
- Cell Death Regulation Group, Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain
| | - G Nuñez
- Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - A Oberst
- Department of Immunology, University of Washington, Seattle, WA, USA
| | - T Panaretakis
- Department of Oncology-Pathology, Cancer Centrum Karolinska (CCK), Karolinska Institute, Stockholm, Sweden
| | - J M Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - M E Peter
- Department of Hematology/Oncology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - M Piacentini
- 1] Department of Biology, University of Rome Tor Vergata; Rome, Italy [2] Department of Epidemiology and Preclinical Research, National Institute for Infectious Diseases Lazzaro Spallanzani, Istituto Ricovero Cura Carattere Scientifico (IRCCS), Rome, Italy
| | - P Pinton
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology and LTTA Center, University of Ferrara, Ferrara, Italy
| | - J H Prehn
- Department of Physiology and Medical Physics, Royal College of Surgeons, Dublin, Ireland
| | - H Puthalakath
- Department of Biochemistry, La Trobe Institute of Molecular Science, La Trobe University, Melbourne, Australia
| | - G A Rabinovich
- Laboratory of Immunopathology, Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - K S Ravichandran
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - R Rizzuto
- Department Biomedical Sciences, University of Padova, Padova, Italy
| | - C M Rodrigues
- Research Institute for Medicines, Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal
| | - D C Rubinsztein
- Department of Medical Genetics, Cambridge Institute for Medical Research, University of Cambridge School of Clinical Medicine, Cambridge, UK
| | - T Rudel
- Department of Microbiology, University of Würzburg; Würzburg, Germany
| | - Y Shi
- Soochow Institute for Translational Medicine, Soochow University, Suzhou, China
| | - H-U Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| | - B R Stockwell
- 1] Howard Hughes Medical Institute (HHMI), Chevy Chase, MD, USA [2] Departments of Biological Sciences and Chemistry, Columbia University, New York, NY, USA
| | - G Szabadkai
- 1] Department Biomedical Sciences, University of Padova, Padova, Italy [2] Department of Cell and Developmental Biology and Consortium for Mitochondrial Research, University College London (UCL), London, UK
| | - S W Tait
- 1] Cancer Research UK Beatson Institute, Glasgow, UK [2] Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - H L Tang
- W Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University, Baltimore, MD, USA
| | - N Tavernarakis
- 1] Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Crete, Greece [2] Department of Basic Sciences, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Y Tsujimoto
- Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - T Vanden Berghe
- 1] VIB Inflammation Research Center, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - P Vandenabeele
- 1] VIB Inflammation Research Center, Ghent, Belgium [2] Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium [3] Methusalem Program, Ghent University, Ghent, Belgium
| | - A Villunger
- Division of Developmental Immunology, Biocenter, Medical University Innsbruck, Innsbruck, Austria
| | - E F Wagner
- Cancer Cell Biology Program, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - H Walczak
- Centre for Cell Death, Cancer and Inflammation (CCCI), UCL Cancer Institute, University College London (UCL), London, UK
| | - E White
- Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - W G Wood
- 1] Department of Pharmacology, University of Minnesota School of Medicine, Minneapolis, MN, USA [2] Geriatric Research, Education and Clinical Center, VA Medical Center, Minneapolis, MN, USA
| | - J Yuan
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Z Zakeri
- 1] Department of Biology, Queens College, Queens, NY, USA [2] Graduate Center, City University of New York (CUNY), Queens, NY, USA
| | - B Zhivotovsky
- 1] Division of Toxicology, Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden [2] Faculty of Fundamental Medicine, Lomonosov Moscow State University, Moscow, Russia
| | - G Melino
- 1] Department of Experimental Medicine and Surgery, University of Rome Tor Vergata, Rome, Italy [2] Medical Research Council Toxicology Unit, Leicester, UK
| | - G Kroemer
- 1] Equipe 11 labellisée par la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, Paris, France [2] Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France [3] INSERM, U1138, Gustave Roussy, Paris, France [4] Metabolomics and Cell Biology Platforms, Gustave Roussy Cancer Center, Villejuif, France [5] Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France
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Affiliation(s)
- C Muñoz-Pinedo
- Cell Death Regulation Group, IDIBELL (Institut d'Investigació Biomèdica de Bellvitge) - Hospital Duran i Reynals 3 planta, Gran Via de L'Hospitalet 199, L'Hospitalet, Barcelona 08908, Spain
| | - S J Martin
- 1] Molecular Cell Biology Laboratory, Department of Genetics, Trinity College, Dublin 2, Ireland [2] Cellular Biotechnology Laboratory, Saint-Petersburg State Institute of Technology, Moskovskii prospekt, Saint Petersburg, Russia
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de Hoz L, Martin SJ. Double dissociation between the contributions of the septal and temporal hippocampus to spatial learning: the role of prior experience. Hippocampus 2014; 24:990-1005. [PMID: 24753035 DOI: 10.1002/hipo.22285] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 04/09/2014] [Accepted: 04/09/2014] [Indexed: 11/09/2022]
Abstract
The mammalian hippocampus is anatomically heterogeneous along its longitudinal axis, and there is evidence that distinct functions are executed by different septotemporal subregions. The best documented example is the dependency of spatial learning on the septal, but not the temporal, hippocampus. Here, we carried out a watermaze memory task in rats with partial lesions of the septal or temporal hippocampus made either before or after training. We then studied memory retention, reversal, and new spatial learning in a novel environment. This resulted in the surprising finding that spatial learning in a new environment is dependent on the temporal hippocampus in rats with preoperative experience of a different pool. Rats with septal hippocampal lesions made after learning not only retained the focused search strategy that was acquired during preoperative training, but were also capable of rapid spatial learning in a second pool. This demonstrates that once spatial information has been acquired in one context, related new learning in a different context can be mediated by the temporal hippocampus, a result that challenges the widely held view that spatial memory is an exclusive function of the septal hippocampus.
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Affiliation(s)
- Livia de Hoz
- Centre for Cognitive and Neural Systems (CCNS), University of Edinburgh, Edinburgh, Scotland, United Kingdom
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Abstract
Abstract
Deception is widespread throughout the animal kingdom and various deceptive strategies are exemplified by social parasites. These are species of ants, bees and wasps that have evolved to invade, survive and reproduce within a host colony of another social species. This is achieved principally by chemical deception that tricks the host workers into treating the invading parasite as their own kin. Achieving levels of acceptance into typically hostile host colonies requires an amazing level of deception as social insects have evolved complex species- and colony-specific recognition systems. This allows the detection of foreigners, both hetero- and con-specific. Therefore, social parasitic ants not only have to overcome the unique species recognition profiles that each ant species produces, but also the subtle variations in theses profiles which generate the colony-specific profiles. We present data on the level of chemical similarity between social parasites and their hosts in four different systems and then discuss these data in the wider context with previous studies, especially in respect to using multivariate statistical methods when looking for differences in these systems.
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Affiliation(s)
- Rhian M. Guillem
- Department of Animal and Plant Sciences, University of Sheffield, S10 2TN, UK
| | - Falko Drijfhout
- Chemical Ecology Group, School of Physical and Geographical Sciences, Lennard-Jones Laboratory, Keele University, ST5 5BGUK
| | - Stephen J. Martin
- School of Environment and Life Sciences, University of Salford, Manchester M5 4WT, UK
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Martin SJ, Hardy J, Villalobos E, Martín-Hernández R, Nikaido S, Higes M. Do the honeybee pathogens Nosema ceranae and deformed wing virus act synergistically? Environ Microbiol Rep 2013; 5:506-10. [PMID: 23864563 PMCID: PMC3806273 DOI: 10.1111/1758-2229.12052] [Citation(s) in RCA: 28] [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] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 02/25/2013] [Indexed: 05/20/2023]
Abstract
The honeybee pathogens Nosema ceranae and deformed wing virus (DWV) cause the collapse of honeybee colonies. Therefore, it is plausible that these two pathogens act synergistically to increase colony losses, since N.ceranae causes damage to the mid-gut epithelial ventricular cells and actively suppresses the honeybees' immune response, either of which could increase the virulence of viral pathogens within the bee. To test this hypothesis we exploited 322 Hawaiian honeybee colonies for which DWV prevalence and load is known. We determined via PCR that N.ceranae was present in 89-95% of these colonies, with no Nosema apis being detected. We found no significant difference in spore counts in colonies infected with DWV and those in which DWV was not detected, either on any of the four islands or across the entire honeybee population. Furthermore, no significant correlation between DWV loads (ΔCT levels) and N.ceranae spore counts was found, so these two pathogens are not acting synergistically. Although the Hawaiian honeybees have the highest known prevalence of N.ceranae in the world, with average number of spores been 2.7 million per bee, no acute Nosema related problems i.e. large-scale colony deaths, have been reported by Hawaiian beekeepers.
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Affiliation(s)
- Stephen J Martin
- School of Environment and Life Sciences, University of Salford, Greater Manchester, M5 4WT, UK.
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Badouin H, Belkhir K, Gregson E, Galindo J, Sundström L, Martin SJ, Butlin RK, Smadja CM. Transcriptome characterisation of the ant Formica exsecta with new insights into the evolution of desaturase genes in social hymenoptera. PLoS One 2013; 8:e68200. [PMID: 23874539 PMCID: PMC3709892 DOI: 10.1371/journal.pone.0068200] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 05/28/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Despite the recent sequencing of seven ant genomes, no genomic data are available for the genus Formica, an important group for the study of eusocial traits. We sequenced the transcriptome of the ant Formica exsecta with the 454 FLX Titanium technology from a pooled sample of workers from 70 Finnish colonies. RESULTS About 1,000,000 reads were obtained from a normalised cDNA library. We compared the assemblers MIRA3.0 and Newbler2.6 and showed that the latter performed better on this dataset due to a new option which is dedicated to improve contig formation in low depth portions of the assemblies. The 29,579 contigs represent 27 Mb. 50% showed similarity with known proteins and 25% could be assigned a category of gene ontology. We found more than 13,000 high-quality single nucleotide polymorphisms. The Δ9 desaturase gene family is an important multigene family involved in chemical communication in insects. We found six Δ9 desaturases in this Formica exsecta transcriptome dataset that were used to reconstruct a maximum-likelihood phylogeny of insect desaturases and to test for signatures of positive selection in this multigene family in ant lineages. We found differences with previous phylogenies of this gene family in ants, and found two clades potentially under positive selection. CONCLUSION This first transcriptome reference sequence of Formica exsecta provided sequence and polymorphism data that will allow researchers working on Formica ants to develop studies to tackle the genetic basis of eusocial phenotypes. In addition, this study provided some general guidelines for de novo transcriptome assembly that should be useful for future transcriptome sequencing projects. Finally, we found potential signatures of positive selection in some clades of the Δ9 desaturase gene family in ants, which suggest the potential role of sequence divergence and adaptive evolution in shaping the large diversity of chemical cues in social insects.
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Affiliation(s)
- Hélène Badouin
- Centre National de la Recherche Scientifique CNRS - Institut des Sciences de l'Evolution UMR 5554, Université Montpellier 2, Montpellier, France.
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Sutton PA, Wilde MJ, Martin SJ, Cvačka J, Vrkoslav V, Rowland SJ. Studies of long chain lipids in insects by high temperature gas chromatography and high temperature gas chromatography–mass spectrometry. J Chromatogr A 2013; 1297:236-40. [DOI: 10.1016/j.chroma.2013.05.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 04/29/2013] [Accepted: 05/01/2013] [Indexed: 11/25/2022]
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Shires KL, Hawthorne JP, Hope AM, Dudchenko PA, Wood ER, Martin SJ. Functional connectivity between the thalamus and postsubiculum: Analysis of evoked responses elicited by stimulation of the laterodorsal thalamic nucleus in anesthetized rats. Hippocampus 2013; 23:559-69. [DOI: 10.1002/hipo.22114] [Citation(s) in RCA: 6] [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] [Accepted: 02/06/2013] [Indexed: 11/06/2022]
Affiliation(s)
- Kate L. Shires
- The University of Edinburgh; Centre for Cognitive and Neural Systems (CCNS); 1 George Square; Edinburgh; EH8 9JZ; United Kingdom
| | - James P. Hawthorne
- The University of Edinburgh; Centre for Cognitive and Neural Systems (CCNS); 1 George Square; Edinburgh; EH8 9JZ; United Kingdom
| | - Alexander M.J. Hope
- The University of Edinburgh; Centre for Cognitive and Neural Systems (CCNS); 1 George Square; Edinburgh; EH8 9JZ; United Kingdom
| | | | - Emma R. Wood
- The University of Edinburgh; Centre for Cognitive and Neural Systems (CCNS); 1 George Square; Edinburgh; EH8 9JZ; United Kingdom
| | - Stephen J. Martin
- The University of Edinburgh; Centre for Cognitive and Neural Systems (CCNS); 1 George Square; Edinburgh; EH8 9JZ; United Kingdom
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Morris RGM, Steele RJ, Bell JE, Martin SJ. N-methyl-d-aspartate receptors, learning and memory: chronic intraventricular infusion of the NMDA receptor antagonist d-AP5 interacts directly with the neural mechanisms of spatial learning. Eur J Neurosci 2013; 37:700-17. [PMID: 23311352 DOI: 10.1111/ejn.12086] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 11/11/2012] [Indexed: 01/03/2023]
Abstract
Three experiments were conducted to contrast the hypothesis that hippocampal N-methyl-d-aspartate (NMDA) receptors participate directly in the mechanisms of hippocampus-dependent learning with an alternative view that apparent impairments of learning induced by NMDA receptor antagonists arise because of drug-induced neuropathological and/or sensorimotor disturbances. In experiment 1, rats given a chronic i.c.v. infusion of d-AP5 (30 mm) at 0.5 μL/h were selectively impaired, relative to aCSF-infused animals, in place but not cued navigation learning when they were trained during the 14-day drug infusion period, but were unimpaired on both tasks if trained 11 days after the minipumps were exhausted. d-AP5 caused sensorimotor disturbances in the spatial task, but these gradually worsened as the animals failed to learn. Histological assessment of potential neuropathological changes revealed no abnormalities in d-AP5-treated rats whether killed during or after chronic drug infusion. In experiment 2, a deficit in spatial learning was also apparent in d-AP5-treated rats trained on a spatial reference memory task involving two identical but visible platforms, a task chosen and shown to minimise sensorimotor disturbances. HPLC was used to identify the presence of d-AP5 in selected brain areas. In Experiment 3, rats treated with d-AP5 showed a delay-dependent deficit in spatial memory in the delayed matching-to-place protocol for the water maze. These data are discussed with respect to the learning mechanism and sensorimotor accounts of the impact of NMDA receptor antagonists on brain function. We argue that NMDA receptor mechanisms participate directly in spatial learning.
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Affiliation(s)
- R G M Morris
- Laboratory for Cognitive Neuroscience, Centre for Cognitive and Neural Systems, The University of Edinburgh, Edinburgh, UK.
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Inglis J, Martin SJ, Morris RGM. Upstairs/downstairs revisited: spatial pretraining-induced rescue of normal spatial learning during selective blockade of hippocampal N-methyl-d-aspartate receptors. Eur J Neurosci 2012; 37:718-27. [PMID: 23278867 DOI: 10.1111/ejn.12087] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 11/11/2012] [Indexed: 11/29/2022]
Abstract
Spatial pretraining can enable spatial learning in another environment that ordinarily requires hippocampal N-methyl-d-aspartate (NMDA) receptor activity to become independent of that activity. This study explored further the circumstances in which this training-induced 'rescue' of later learning in the presence of the NMDA receptor antagonist 2-amino-5-phosphonovaleric acid (D-AP5) can occur. D-AP5 (0, 10, 20 and 30 mm in artificial cerebrospinal fluid) was infused continuously (0.5 μL/h, from a minipump) and bilaterally into the dorsal hippocampus during spatial-reference-memory training in a watermaze (4 trials/day, 8 days). This was preceded either by handling only or by identical spatial training in another watermaze in a separate laboratory with different extramaze cues. In naïve rats, D-AP5 caused a dose-related impairment in spatial reference memory acquisition that was significant at the lowest 5 nm/h infusion concentration. In pretrained rats, the dose-response function was shifted such that, in watermaze 2, spatial learning was normal at this low concentration, with a deficit at higher infusion concentrations. The induction of long-term potentiation in the dentate gyrus in vivo was blocked at all D-AP5 concentrations. Sensorimotor abnormalities sometimes seen with NMDA receptor antagonists were only apparent at the highest concentration. The implication of this paradoxical dissociation between hippocampal NMDA receptor-dependent plasticity and spatial learning is discussed with reference to two rival hypotheses of the impact of pretraining.
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Affiliation(s)
- Jennifer Inglis
- Laboratory for Cognitive Neuroscience, Centre for Cognitive and Neural Systems, The University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
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Martin SJ, Shires KL, Spooner PA. The relationship between tetanus intensity and the magnitude of hippocampal long-term potentiation in vivo. Neuroscience 2012; 231:363-72. [PMID: 23228809 PMCID: PMC3746156 DOI: 10.1016/j.neuroscience.2012.11.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 11/12/2012] [Accepted: 11/29/2012] [Indexed: 01/05/2023]
Abstract
In this study, we assessed the effects of varying tetanus and test-pulse intensity on the magnitude of long-term potentiation (LTP) in the perforant path–dentate gyrus projection of urethane-anaesthetized rats. We developed a novel within-subjects procedure in which test-pulse-stimulation intensity (60–1000 μA) was varied quasi-randomly under computer control throughout the recording period. After a baseline period, we applied a high-frequency tetanus, the intensity of which was varied over the same range as test-pulse intensity, but between subjects. The time-course of LTP was thus monitored continuously across a range of test-pulse intensities in each rat. Intense high-frequency tetanization at 1000 μA resulted in a paradoxical depression of the dentate field excitatory post-synaptic potential (fEPSP) slope at the lowest test intensity used (60 μA), but caused a potentiation at higher test intensities in the same animal. Moreover, intense tetanization induced less LTP than a moderate tetanus over most of the test-intensity range. Explanations for this pattern of data include a potentiation of feed-forward inhibition in conjunction with LTP of excitatory neurotransmission, or local tissue damage at the stimulation site. To address this issue, we conducted an additional experiment in which a second stimulating electrode was placed in the perforant path at a site closer to the dentate, in order to activate a common population of afferents at a location ‘downstream’ of the original stimulation site. After 1000-μA tetanization of the original (‘upstream’) site, fEPSPs were again depressed in response to test stimulation of the upstream site, but only potentiation was observed in response to stimulation of the downstream site. This is consistent with the idea that the depression induced by intense tetanization results from local changes at the stimulation site. In conclusion, while tetanus intensity must exceed the LTP induction threshold, intensities above 500 μA should be avoided; in the present study, tetanization at 250–500 μA yielded maximal levels of LTP.
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Affiliation(s)
- S J Martin
- Centre for Cognitive and Neural Systems, The University of Edinburgh, 1 George Square, Edinburgh EH8 9JZ, Scotland, UK.
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Affiliation(s)
- Declan C Schroeder
- The Marine Biological Association of the United Kingdom, Citadel Hill, Plymouth UK.
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