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Mullineaux ST, McKinley JM, Marks NJ, Doherty R, Scantlebury DM. A nose for trouble: ecotoxicological implications for climate change and disease in Saiga antelope (S. t. tatarica). Environ Geochem Health 2024; 46:93. [PMID: 38367154 PMCID: PMC10874336 DOI: 10.1007/s10653-024-01874-y] [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] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 01/12/2024] [Indexed: 02/19/2024]
Abstract
In recent decades, Saiga antelope (Saiga t. tatarica) mass die-offs have become more common. The mass die-off of 2015 in central Kazakhstan, recorded 140,000 individual deaths across multiple herds. Previously, research has shown atmospheric humidity, the bacterium Pasteurella multocida serotype B, and resultant haemorrhagic septicaemia, were the primary cause. However, other synergistic factors may have impacted this process. Here we use a multivariate compositional data analysis (CoDA) approach to assess what other factors may have been involved. We show a pollutant linkage mechanism where relative humidity and dewpoint temperature combine with environmental pollutants, potentially toxic elements (e.g., Hg, As), complex carbon compounds (e.g., Acetone, Toluene), and inorganic compounds (e.g., CHx, SO2) which affected the Saiga during the calving season (start and peak) and at the onset of the mass die-off. We suggest a mechanism for this process. Upon arrival at their carving grounds, the Saiga experienced a sudden precipitation event, a spike in temperatures, and resultant high humidity occurs. The infectious bacterium P. multocida serotype B then spreads. Further, environmental pollutants contained within steppe soils are released to the air, forming localised smog events, these synergistically combine, and mass die-off occurs.
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Affiliation(s)
- S T Mullineaux
- School of Natural and Built Environment, Queen's University Belfast, Belfast, Northern Ireland, UK.
| | - J M McKinley
- School of Natural and Built Environment, Queen's University Belfast, Belfast, Northern Ireland, UK
| | - N J Marks
- School of Biological Sciences, Queen's University Belfast, Belfast, Northern Ireland, UK
| | - R Doherty
- School of Natural and Built Environment, Queen's University Belfast, Belfast, Northern Ireland, UK
| | - D M Scantlebury
- School of Biological Sciences, Queen's University Belfast, Belfast, Northern Ireland, UK
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Magowan EA, Maguire IE, Smith S, Redpath S, Marks NJ, Wilson RP, Menzies F, O’Hagan M, Scantlebury DM. Dead-reckoning elucidates fine-scale habitat use by European badgers Meles meles. Anim Biotelemetry 2022; 10:10. [PMID: 37521810 PMCID: PMC8908954 DOI: 10.1186/s40317-022-00282-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 02/23/2022] [Indexed: 05/03/2023]
Abstract
Background Recent developments in both hardware and software of animal-borne data loggers now enable large amounts of data to be collected on both animal movement and behaviour. In particular, the combined use of tri-axial accelerometers, tri-axial magnetometers and GPS loggers enables animal tracks to be elucidated using a procedure of 'dead-reckoning'. Although this approach was first suggested 30 years ago by Wilson et al. (1991), surprisingly few measurements have been made in free-ranging terrestrial animals. The current study examines movements, interactions with habitat features, and home-ranges calculated from just GPS data and also from dead-reckoned data in a model terrestrial mammal, the European badger (Meles meles). Methods Research was undertaken in farmland in Northern Ireland. Two badgers (one male, one female) were live-trapped and fitted with a GPS logger, a tri-axial accelerometer, and a tri-axial magnetometer. Thereafter, the badgers' movement paths over 2 weeks were elucidated using just GPS data and GPS-enabled dead-reckoned data, respectively. Results Badgers travelled further using data from dead-reckoned calculations than using the data from only GPS data. Whilst once-hourly GPS data could only be represented by straight-line movements between sequential points, the sub-second resolution dead-reckoned tracks were more tortuous. Although there were no differences in Minimum Convex Polygon determinations between GPS- and dead-reckoned data, Kernel Utilisation Distribution determinations of home-range size were larger using the former method. This was because dead-reckoned data more accurately described the particular parts of landscape constituting most-visited core areas, effectively narrowing the calculation of habitat use. Finally, the dead-reckoned data showed badgers spent more time near to field margins and hedges than simple GPS data would suggest. Conclusion Significant differences emerge when analyses of habitat use and movements are compared between calculations made using just GPS data or GPS-enabled dead-reckoned data. In particular, use of dead-reckoned data showed that animals moved 2.2 times farther, had better-defined use of the habitat (revealing clear core areas), and made more use of certain habitats (field margins, hedges). Use of dead-reckoning to provide detailed accounts of animal movement and highlight the minutiae of interactions with the environment should be considered an important technique in the ecologist's toolkit.
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Affiliation(s)
- E. A. Magowan
- School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL Northern Ireland UK
- Randox Laboratories Ltd. Crumlin, Antrim, Northern Ireland UK
| | - I. E. Maguire
- School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL Northern Ireland UK
- Randox Laboratories Ltd. Crumlin, Antrim, Northern Ireland UK
| | - S. Smith
- School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL Northern Ireland UK
| | - S. Redpath
- School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL Northern Ireland UK
| | - N. J. Marks
- School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL Northern Ireland UK
| | - R. P. Wilson
- Department of Biological Sciences, Institute of Environmental Sustainability, Swansea University, Swansea, UK
| | - F. Menzies
- Department of Agriculture, Environment and Rural Affairs, Veterinary Epidemiology Unit, Belfast, UK
| | - M. O’Hagan
- Department of Agriculture, Environment and Rural Affairs, Veterinary Epidemiology Unit, Belfast, UK
| | - D. M. Scantlebury
- School of Biological Sciences, Queen’s University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL Northern Ireland UK
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Mullineaux ST, McKinley JM, Marks NJ, Scantlebury DM, Doherty R. Heavy metal (PTE) ecotoxicology, data review: Traditional vs. a compositional approach. Sci Total Environ 2021; 769:145246. [PMID: 33736251 DOI: 10.1016/j.scitotenv.2021.145246] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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: 11/19/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 06/12/2023]
Abstract
Potentially Toxic Elements (PTEs) otherwise known as heavy metals are ubiquitous in soils and can have a range of negative health and environmental impacts. In terrestrial systems understanding how PTEs move in the environment is made challenging by the complex interactions within soil and the wider environment and the compositional nature of PTEs. PTEs are compositional because data of individual PTEs within in a sample are ratios which may be under a sum constraint, where individual components sum up to a whole. In this study three different scenarios were considered, one using the centred log ratio transformation (clr) a compositional transformation, the more "traditional" log10 transformation (log10) and untransformed data acting as a comparison (unt) were applied to four different datasets. Three were the Liver, Muscle and Kidney tissue of Eurasian Badgers (Meles meles) and the fourth was soil and data were extracted from a regional geospatial survey. Cluster analysis demonstrated that the clr and log10 transformation were able to resolve compositional trends at the point of the individual sample, whilst unt could not and did not meet the preconditions for the next phase of analysis. At the level of compositional trends between PTEs complex heatmaps demonstrated that clr was able to isolate PTE relationships and highlight commonalities between different datasets, whilst log10 could not. In the final phase, principal component analysis (PCA) of the clr transformation showed similarities between the signals in the soft tissues and the disparities they had with soil, whilst the log10 transformation was unable to achieve this. Overall, the clr transformation was shown to perform more consistently under a variety of analytical scenarios and the compositional approach will provide more realistic interpretations about PTEs in both soil and animal soft tissue than the log10 or unt conditions.
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Affiliation(s)
- S T Mullineaux
- School of Biological Sciences, 1-33 Chlorine Gardens, Belfast BT9 5AJ, United Kingdom of Great Britain and Northern Ireland.
| | - J M McKinley
- School of Natural and Built Environment, Elmwood Avenue, Belfast BT7 1NN, United Kingdom of Great Britain and Northern Ireland
| | - N J Marks
- School of Biological Sciences, 1-33 Chlorine Gardens, Belfast BT9 5AJ, United Kingdom of Great Britain and Northern Ireland
| | - D M Scantlebury
- School of Biological Sciences, 1-33 Chlorine Gardens, Belfast BT9 5AJ, United Kingdom of Great Britain and Northern Ireland
| | - R Doherty
- School of Natural and Built Environment, David Keir Building, Stranmillis Road, Belfast BT9 5AG, United Kingdom of Great Britain and Northern Ireland
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Mullineaux ST, Redpath SHA, Ogle N, McKinley JM, Marks NJ, Scantlebury DM, Doherty R. Potentially toxic element accumulation in badgers (Meles meles): a compositional approach. Sci Total Environ 2021; 762:143087. [PMID: 33131870 DOI: 10.1016/j.scitotenv.2020.143087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/09/2020] [Accepted: 10/11/2020] [Indexed: 06/11/2023]
Abstract
Potentially Toxic Elements (PTEs) in Badgers (Meles meles), otherwise known as heavy metals, are unique amongst environmental pollutants occurring, both naturally and anthropogenically. PTEs have a broad range of negative health and environmental effects, therefore identifying their sources and pathways through the environment is imperative for public health policy. This is difficult in terrestrial systems due to the compositional nature of soil geochemistry. In this study, a compositional statistical approach was used to identify how PTEs accumulate in a terrestrial carnivorous mammal, Eurasian Badgers (Meles meles). Compositional principal component analysis (PCA) was used on geochemical data from the Tellus survey, the soil baseline and badger tissue data to map geo-spatial patterns of PTEs and show accumulative trends measured in time. Mapping PCs identified distinct regions of PTE presence in soil and PTE accumulation in badger tissues in Northern Ireland. PTEs were most elevated in liver, kidney and then muscle tissues. Liver and kidney showed the most distinct geo-spatial patterns of accumulation and muscle was the most depleted. PC1 and 2 for each type were modelled using generalised additive mixed models (GAMM) to identify trends through time. PC1 for the liver and muscle were associated with rainfall and ∂N15 in the liver, showing a link to diet and a bioaccumulation pathway, whilst PC2 for both tissues was associated with mean temperature, showing a link to seasonal activity and a bioaccessibility pathway. However, in kidney tissue these trends are reversed and PC1 was associated with bioaccessibility and PC2 with bioaccumulation. Combined these techniques can elucidate both geo-spatial trends in PTEs and the mechanisms by which they move in environment and in future may be an effective tool for assessing PTE bioavailability in environmental health surveys.
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Affiliation(s)
- S T Mullineaux
- School of Biological Sciences, 1-33 Chlorine Gardens, Belfast BT9 5AJ, United Kingdom of Great Britain and Northern Ireland.
| | - S H A Redpath
- School of Biological Sciences, 1-33 Chlorine Gardens, Belfast BT9 5AJ, United Kingdom of Great Britain and Northern Ireland
| | - N Ogle
- School of Natural and Built Environment, David Keir Building, Stranmillis Road, Belfast BT9 5AG, United Kingdom of Great Britain and Northern Ireland
| | - J M McKinley
- School of Natural and Built Environment, Elmwood Avenue, Belfast BT7 1NN, United Kingdom of Great Britain and Northern Ireland
| | - N J Marks
- School of Biological Sciences, 1-33 Chlorine Gardens, Belfast BT9 5AJ, United Kingdom of Great Britain and Northern Ireland
| | - D M Scantlebury
- School of Biological Sciences, 1-33 Chlorine Gardens, Belfast BT9 5AJ, United Kingdom of Great Britain and Northern Ireland
| | - R Doherty
- School of Natural and Built Environment, David Keir Building, Stranmillis Road, Belfast BT9 5AG, United Kingdom of Great Britain and Northern Ireland
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Abstract
The dictum that patients who have plastic ventilation tubes (grommets) inserted in their tympanic membranes should not go swimming is questioned. A theoretical assessment is made of the pressure necessary to push water through a grommet. This value is compared with practical observations. These values are discussed with reference to chemical and bacteriological hazards and it is concluded that water is unlikely to enter the middle ear in surface swimming, and even when diving underwater the chances of setting up an otitis media must be small.
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Affiliation(s)
- N J Marks
- ENT Department, Guy's Hospital, London SE1 9RT
| | - R P Mills
- ENT Department, Guy's Hospital, London SE1 9RT
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Bidder OR, Walker JS, Jones MW, Holton MD, Urge P, Scantlebury DM, Marks NJ, Magowan EA, Maguire IE, Wilson RP. Step by step: reconstruction of terrestrial animal movement paths by dead-reckoning. Mov Ecol 2015; 3:23. [PMID: 26380711 PMCID: PMC4572461 DOI: 10.1186/s40462-015-0055-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 09/06/2015] [Indexed: 05/02/2023]
Abstract
BACKGROUND Research on wild animal ecology is increasingly employing GPS telemetry in order to determine animal movement. However, GPS systems record position intermittently, providing no information on latent position or track tortuosity. High frequency GPS have high power requirements, which necessitates large batteries (often effectively precluding their use on small animals) or reduced deployment duration. Dead-reckoning is an alternative approach which has the potential to 'fill in the gaps' between less resolute forms of telemetry without incurring the power costs. However, although this method has been used in aquatic environments, no explicit demonstration of terrestrial dead-reckoning has been presented. RESULTS We perform a simple validation experiment to assess the rate of error accumulation in terrestrial dead-reckoning. In addition, examples of successful implementation of dead-reckoning are given using data from the domestic dog Canus lupus, horse Equus ferus, cow Bos taurus and wild badger Meles meles. CONCLUSIONS This study documents how terrestrial dead-reckoning can be undertaken, describing derivation of heading from tri-axial accelerometer and tri-axial magnetometer data, correction for hard and soft iron distortions on the magnetometer output, and presenting a novel correction procedure to marry dead-reckoned paths to ground-truthed positions. This study is the first explicit demonstration of terrestrial dead-reckoning, which provides a workable method of deriving the paths of animals on a step-by-step scale. The wider implications of this method for the understanding of animal movement ecology are discussed.
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Affiliation(s)
- O. R. Bidder
- />Institut für Terrestrische und Aquatische Wildtierforschung, Stiftung Tierärztliche Hochschule, Hannover, Werfstr. 6, 25761 Büsum, Germany
| | - J. S. Walker
- />Department of Computer Science, College of Science, Swansea University, Singleton Park, Swansea, SA2 8PP, Wales UK
| | - M. W. Jones
- />Department of Computer Science, College of Science, Swansea University, Singleton Park, Swansea, SA2 8PP, Wales UK
| | - M. D. Holton
- />College of Engineering, Swansea University, Singleton Park, Swansea, SA2 8PP Wales UK
| | - P. Urge
- />Faculté des Sciences de la Vie, Master d’Ecophysiologie et Ethologie, Université de Strasbourg, 28 rue Goethe, 67083 Strasbourg Cedex, France
| | - D. M. Scantlebury
- />School of Biological Sciences, Institute for Global Food Security, Queen’s University Belfast, Belfast, BT9 7BL Northern Ireland UK
| | - N. J. Marks
- />School of Biological Sciences, Institute for Global Food Security, Queen’s University Belfast, Belfast, BT9 7BL Northern Ireland UK
| | - E. A. Magowan
- />School of Biological Sciences, Institute for Global Food Security, Queen’s University Belfast, Belfast, BT9 7BL Northern Ireland UK
| | - I. E. Maguire
- />School of Biological Sciences, Institute for Global Food Security, Queen’s University Belfast, Belfast, BT9 7BL Northern Ireland UK
| | - R. P. Wilson
- />Swansea Lab for Animal Movement, Biosciences, College of Science, Swansea University, Singleton Park, Swansea, SA2 8PP Wales UK
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Scantlebury M, Maher McWilliams M, Marks NJ, Dick JTA, Edgar H, Lutermann H. Effects of life-history traits on parasite load in grey squirrels. J Zool (1987) 2010. [DOI: 10.1111/j.1469-7998.2010.00734.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Mousley A, Maule AG, Halton DW, Marks NJ. Inter-phyla studies on neuropeptides: the potential for broad-spectrum anthelmintic and/or endectocide discovery. Parasitology 2007; 131 Suppl:S143-67. [PMID: 16569287 DOI: 10.1017/s0031182005008553] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Flatworm, nematode and arthropod parasites have proven their ability to develop resistance to currently available chemotherapeutics. The heavy reliance on chemotherapy and the ability of target species to develop resistance has prompted the search for novel drug targets. In view of its importance to parasite/pest survival, the neuromusculature of parasitic helminths and pest arthropod species remains an attractive target for the discovery of novel endectocide targets. Exploitation of the neuropeptidergic system in helminths and arthropods has been hampered by a limited understanding of the functional roles of individual peptides and the structure of endogenous targets, such as receptors. Basic research into these systems has the potential to facilitate target characterization and its offshoots (screen development and drug identification). Of particular interest to parasitologists is the fact that selected neuropeptide families are common to metazoan pest species (nematodes, platyhelminths and arthropods) and fulfil specific roles in the modulation of muscle function in each of the three phyla. This article reviews the inter-phyla activity of two peptide families, the FMRFamide-like peptides and allatostatins, on motor function in helminths and arthropods and discusses the potential of neuropeptide signalling as a target system that could uncover novel endectocidal agents.
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Affiliation(s)
- A Mousley
- Parasitology Research Group, School of Biology and Biochemistry, Queen's University Belfast, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland, UK.
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Moffett CL, Beckett AM, Mousley A, Geary TG, Marks NJ, Halton DW, Thompson DP, Maule AG. The ovijector of Ascaris suum: multiple response types revealed by Caenorhabditis elegans FMRFamide-related peptides. Int J Parasitol 2003; 33:859-76. [PMID: 12865086 DOI: 10.1016/s0020-7519(03)00109-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Caenorhabditis elegans possesses 22 FMRFamide-like peptide (flp) genes predicted to encode 60 different FMRFamide-related peptides with a range of C-terminal signatures. Peptides from five flp genes (1, 6, 8, 9 and 14) are known to modulate the ovijector of Ascaris suum in vitro. This study examines the physiological effects of peptides from the remaining 17 flp genes such that the variety of FMRFamide-related peptide-induced ovijector response types can be delineated. Five categories of response were identified according to the pattern of changes in contractile behaviour and baseline tension. Peptides encoded on 16 flp genes (1, 2, 3, 4, 6, 7, 9, 10, 11, 12, 13, 14, 15, 16, 17 and 20) had qualitatively similar inhibitory (response type 1) actions, with the lowest activity thresholds (1 nM) recorded for peptides with FIRFamide or FLRFamide C-terminal signatures. Peptides encoded on four flp genes (2, 18, 19 and 21), and on the A. suum afp-1 gene, had excitatory actions on the ovijector (response type 2), with PGVLRFamides having the lowest activity threshold (1 nM). An flp-2 peptide (LRGEPIRFamide) induced a transient contraction of the ovijector (activity threshold, 10nM) that was designated response type 3. Response type 4 comprised a transient contraction followed by an extended period of inactivity and was observed with peptides encoded on flp-5 (AGAKFIRFamide, APKPKFIRFamide), flp-8 (KNEFIRFamide) and flp-22 (SPSAKWMRFamide). SPSAKWMRFamide was the most potent peptide tested with an activity threshold of 0.1 nM. A single peptide (AMRNALVRFamide; activity threshold 0.1 microM), encoded on flp-11, induced response type 5, a shortening of the ovijector coupled with an increase in contraction frequency. Although most flp genes encode structurally related peptides that trigger one of the five ovijector response types, flp-2 and flp-11 co-encode FMRFamide-related peptides that induce distinct responses. Within the ovijector of A. suum FaRPs play a complex role involving at least five receptor subtypes or signalling pathways.
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Affiliation(s)
- C L Moffett
- Parasitology Research Group, School of Biology and Biochemistry, Queen's University Belfast, 97, Lisburn Road, Belfast BT9 7BL, Northern Ireland, UK
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Stewart MT, Mousley A, Koubková B, Sebelová S, Marks NJ, Halton DW. Gross anatomy of the muscle systems and associated innervation of Apatemon cobitidis proterorhini metacercaria (Trematoda: Strigeidea), as visualized by confocal microscopy. Parasitology 2003; 126:273-82. [PMID: 12666886 DOI: 10.1017/s0031182002002780] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The major muscle systems of the metacercaria of the strigeid trematode, Apatemon cobitidis proterorhini have been examined using phalloidin as a site-specific probe for filamentous actin. Regional differences were evident in the organization of the body wall musculature of the forebody and hindbody, the former comprising outer circular, intermediate longitudinal and inner diagonal fibres, the latter having the inner diagonal fibres replaced with an extra layer of more widely spaced circular muscle. Three orientations of muscle fibres (equatorial, meridional, radial) were discernible in the oral sucker, acetabulum and paired lappets. Large longitudinal extensor and flexor muscles project into the hindbody where they connect to the body wall or end blindly. Innervation to the muscle systems of Apatemon was examined by immunocytochemistry, using antibodies to known myoactive substances: the flatworm FMRFamide-related neuropeptide (FaRP), GYIRFamide, and the biogenic amine, 5-hydroxytryptamine (5-HT). Strong immunostaining for both peptidergic and serotoninergic components was found in the central nervous system and confocal microscopic mapping of the distribution of these neuroactive substances revealed they occupied separate neuronal pathways. In the peripheral nervous system, GYIRFamide-immunoreactivity was extensive and, in particular, associated with the innervation of all attachment structures; serotoninergic fibres, on the other hand, were localized to the oral sucker and pharynx and to regions along the anterior margins of the forebody.
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Affiliation(s)
- M T Stewart
- Parasitology Research Group, School of Biology and Biochemistry, Medical Biology Centre, Queen's University Belfast, Belfast BT9 7BL, UK
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Thompson DP, Davis JP, Larsen MJ, Coscarelli EM, Zinser EW, Bowman JW, Alexander-Bowman SJ, Marks NJ, Geary TG. Effects of KHEYLRFamide and KNEFIRFamide on cyclic adenosine monophosphate levels in Ascaris suum somatic muscle. Int J Parasitol 2003; 33:199-208. [PMID: 12633657 DOI: 10.1016/s0020-7519(02)00259-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
KHEYLRF-NH(2) (AF2) is a FMRFamide-related peptide (FaRP) present in parasitic and free-living nematodes. At concentrations as low as 10 pM, AF2 induces a biphasic tension response, consisting of a transient relaxation followed by profound excitation, in neuromuscular strips prepared from Ascaris suum. In the present study, the effects of AF2 on cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP) and inositol-1,4,5-triphosphate (IP(3)) levels were measured following muscle tension recordings from 2 cm neuromuscular strips prepared from adult A. suum. AF2 induced a concentration- and time-dependent increase in cAMP, beginning at 1 nM; cAMP levels increased by 84-fold following 1 h exposure to 1 microM AF2. cGMP and IP(3) levels were unaffected by AF2 at concentrations </=1 microM. AF2-induced stimulation of cAMP was unaffected by removal of the dorsal or ventral nerve cord, even though this form of denervation abolished the excitatory phase of the tension response. The effects of 0.1 and 1 microM AF2 on cAMP were also unaffected by 10 microM SDPNFLRF-NH(2) (PF1, an inhibitory FaRP) and 10 microM PF1022A (an inhibitory cyclodepsipeptide), even though each of these peptides abolished the excitatory phase of the tension response induced by AF2. Within an alanine-scan series of AF2 analogues, only KHAYLRF-NH(2) stimulated cAMP production with equipotency to AF2; the effects of this peptide on muscle tension also mimicked AF2. Another excitatory FaRP present in nematodes, KNEFIRF-NH(2) (AF1), also stimulated cAMP production, but was 100-fold less potent than AF2. The stimulatory effects of AF1 on tension and cAMP levels were blocked by an alanine-substituted analogue of this peptide (Ala(6)-AF1, KNEFIAF-NH(2)), while the stimulatory effects of AF2 on tension and cAMP were not affected by this analogue. AF2 and AF1 increase A. suum somatic muscle cAMP by targeting different receptors. Increases in cAMP stimulated by AF2 can be decoupled from the excitatory response caused by this peptide, and it is not possible to establish a causal linkage between the contractile response elicited by this peptide and its effects on cAMP accumulation.
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Affiliation(s)
- D P Thompson
- Pharmacia Animal Health, 7923-25-410, 7000 Portage Road, Kalamazoo, MI 49001-0199, USA.
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Marks NJ, Shaw C, Halton DW, Thompson DP, Geary TG, Li C, Maule AG. Isolation and preliminary biological assessment of AADGAPLIRFamide and SVPGVLRFamide from Caenorhabditis elegans. Biochem Biophys Res Commun 2001; 286:1170-6. [PMID: 11527423 DOI: 10.1006/bbrc.2001.5524] [Citation(s) in RCA: 30] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To date, 9 FMRFamide-related peptides (FaRPs) have been structurally characterised from Caenorhabditis elegans. Radioimmunometrical screening of an ethanolic extract of C. elegans revealed the presence of two additional FaRPs that were purified by reverse-phase HPLC and subjected to Edman degradation analysis and gas-phase sequencing. Unequivocal primary structures for the two FaRPs were determined as Ala-Ala-Asp-Gly-Ala-Pro-Leu-Ile-Arg-Phe-NH(2) and Ser-Val-Pro-Gly-Val-Leu-Arg-Phe-NH(2). Using MALDI-TOF mass spectrometry, the molecular masses of the peptides were found to be 1032 Da (MH) and 875 Da (MH)(+), respectively. Two copies of AADGAPLIRFamide are predicted to be encoded on the precursor gene termed flp-13, while one copy of SVPGVLRFamide is located on flp-18. Synthetic replicates of the peptides were tested on Ascaris suum somatic muscle to assess bioactivity. ADDGAPLIRFamide had inhibitory effects on A. suum muscle strips, which occurred over a range of concentrations from a threshold for activity of 10 nM to 10 microM. SVPGVLRFamide was excitatory on A. suum somatic musculature from a threshold concentration for activity of 1 nM to 10 microM. The inhibitory and excitatory effects of AADGAPLIRFamide and SVPGVLRFamide, respectively, were the same for dorsal and ventral muscle strips as well as innervated and denervated preparations, suggesting that these physiological effects are not nerve cord dependent. Addition of ADDGAPLIRFamide (10 microM) to muscle strips preincubated in high-K(+) and -Ca(2+)-free medium resulted in a normal inhibitory response. Peptide addition to muscle strips preincubated in Cl(-)-free medium showed no inhibitory response, suggesting that the inhibitory response of the peptide may be chloride mediated. A normal excitatory response was noted following the addition of 10 microM SVPGVLRFamide to muscle strips preincubated in high-K(+), Ca(2+)- and Cl(-)-free media.
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Affiliation(s)
- N J Marks
- Parasitology Research Group, Queen's University Belfast, Belfast, Northern Ireland, BT9 7BL, United Kingdom.
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Fellowes RA, Maule AG, Martin RJ, Geary TG, Thompson DP, Kimber MJ, Marks NJ, Halton DW. Classical neurotransmitters in the ovijector of Ascaris suum: localization and modulation of muscle activity. Parasitology 2000; 121 ( Pt 3):325-36. [PMID: 11085252 DOI: 10.1017/s0031182099006290] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Ascaris suum possesses a well-developed nervous system which is regulated by a number of classical neurotransmitters including acetylcholine (ACh), gamma-aminobutyric acid (GABA), glutamate and serotonin. The vagina vera, the distal part of the ovijector, displays intrinsic, rhythmic activity which has been shown to be modulated by FMRFamide-related peptides (FaRPs) in vitro. Confocal scanning laser microscopy coupled with immunocytochemistry, and histochemical studies, revealed that the nerve plexus of the ovijector contains GABAergic and glutamatergic innervation. Although no distinctive cholinergic or serotoninergic innervation was apparent, cholinesterase activity was localized to discrete areas of the musculature of the vagina vera. The effects of classical transmitters on the activity of the vagina vera in vitro were examined. ACh was excitatory, stimulating a brief but powerful contraction of the vagina vera with a threshold for activity of 1 microM. Both GABA and glutamate were inhibitory, causing a cessation of contractile activity at high concentrations (> 10 microM). Although less potent than glutamate, GABA had more profound effects and induced longer-lasting paralysis of the tissue. The threshold concentrations for activity were 5 microM for glutamate and 10 microM for GABA. Serotonin had no consistent effect on the vagina vera. This study demonstrates that classical transmitters modulate the activity of the ovijector of A. suum.
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Affiliation(s)
- R A Fellowes
- Parasitology Research Group, School of Biology and Biochemistry, The Queen's University of Belfast, UK
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Geary TG, Marks NJ, Maule AG, Bowman JW, Alexander-Bowman SJ, Day TA, Larsen MJ, Kubiak TM, Davis JP, Thompson DP. Pharmacology of FMRFamide-related peptides in helminths. Ann N Y Acad Sci 2000; 897:212-27. [PMID: 10676450 DOI: 10.1111/j.1749-6632.1999.tb07893.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nervous systems of helminths are highly peptidergic. Species in the phylum Nematoda (roundworms) possess at least 50 FMRFamide-related peptides (FaRPs), with more yet to be identified. To date, few non-FaRP neuropeptides have been identified in these organisms, though evidence suggests that other families are present. FaRPergic systems have important functions in nematode neuromuscular control. In contrast, species in the phylum Platyhelminthes (flatworms) apparently utilize fewer FaRPs than do nematodes; those species examined possess one or two FaRPs. Other neuropeptides, such as neuropeptide F (NPF), play key roles in flatworm physiology. Although progress has been made in the characterization of FaRP pharmacology in helminths, much remains to be learned. Most studies on nematodes have been done with Ascaris suum because of its large size. However, thanks to the Caenorhabditis elegans genome project, we know most about the FaRP complement of this free-living animal. That essentially all C. elegans FaRPs are active on at least one A. suum neuromuscular system argues for conservation of ligand-receptor recognition features among the Nematoda. Structure-activity studies on nematode FaRPs have revealed that structure-activity relationship (SAR) "rules" differ considerably among the FaRPs. Second messenger studies, along with experiments on ionic dependence and anatomical requirements for activity, reveal that FaRPs act through many different mechanisms. Platyhelminth FaRPs are myoexcitatory, and no evidence exists of multiple FaRP receptors in flatworms. Interestingly, there are examples of cross-phylum activity, with some nematode FaRPs being active on flatworm muscle. The extent to which other invertebrate FaRPs show cross-phylum activity remains to be determined. How FaRPergic nerves contribute to the control of behavior in helminths, and are integrated with non-neuropeptidergic systems, also remains to be elucidated.
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Affiliation(s)
- T G Geary
- Animal Health Discovery Research, Pharmacia & Upjohn, Kalamazoo, Michigan 49007-4940, USA.
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Fellowes RA, Maule AG, Marks NJ, Geary TG, Thompson DP, Halton DW. Nematode neuropeptide modulation of the vagina vera of Ascaris suum: in vitro effects of PF1, PF2, PF4, AF3 and AF4. Parasitology 2000; 120 ( Pt 1):79-89. [PMID: 10726269 DOI: 10.1017/s0031182099005260] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Ascaris suum possesses a large number of FMRFamide-related peptides (FaRPs) of which KNEFIRFamide (AF1), KHEYLRFamide (AF2) and KSAYMRFamide (AF8/PF3) have been shown to modulate the intrinsic, rhythmic activity of the vagina vera of A. suum in vitro. In the present study, the effects of the nematode FaRPs, SDPNFLRFamide (PF1), SADPNFLREamide (PF2) and KPNFIRFamide (PF4) (from Panagrellus redivivus) and AVPGVLRFamide (AF3) and GDVPGVLRFamide (AF4) (from A. suum) on the in vitro activity of the vagina vera were examined. The effects of each of the peptides were qualitatively and quantitatively distinct. All 3 FaRPs from P. redivivus were inhibitory, causing a cessation of contractions. PF2 was 3 times more potent than PF1, with a threshold of 1 nM. Although PF4 was the least potent (threshold, 10 nM), its effects at > or = 10 nM were quantitatively the greatest. Both AF3 and AF4 (1 microM) induced complex, multiphasic responses consisting of an initial contraction and spastic paralysis followed by a return of contractile activity of increased amplitude. AF3 was 3 times more potent than AF4. The effects of these peptides had some similarities to those observed on A. suum somatic body wall muscle in vitro, with PF1, PF2 and PF4 being inhibitory and AF3 and AF4 being excitatory.
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Affiliation(s)
- R A Fellowes
- Parasitology Research Group, School of Biology and Biochemistry, Queen's University of Belfast, UK
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Abstract
This study used electron microscopy and confocal scanning laser microscopy interfaced with cytochemistry to study neuromuscular interrelationships in the ovijector of Ascaris suum. An extensive nerve plexus with both FaRPergic and non-FaRPergic components extends over the outer surface of the ovijector. The non-FaRPergic component is derived from nerve branches of the ventral nerve cord, whereas the FaRPergic component emanates from two large FMRFamide-immunoreactive neurons. In the vagina vera, most myofibrils are circular in orientation and a number of them divide and run for short distances in longitudinal and diagonal directions, their myofilaments are also orientated in a variety of directions. Parallel nerve fibres run in tracts along the length of the vagina vera with branches that penetrate the muscle layers. The vagina uteri possesses a thicker hypodermis than that of the vagina vera. It appears rich in secretory and phagocytic vesicles and the luminal side is invested with an electron-dense substance. The musculature of the vagina uteri is less well developed than that of the vagina vera, being restricted to circular myofibrils, with an apparent diagonal arrangement of myofilaments. Also, the innervation is less extensive in the vagina uteri with many fibres returning to the vagina vera to rejoin the nerve net and others continuing into the uteri.
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Affiliation(s)
- R A Fellowes
- Parasitology Research Group, The School of Biology and Biochemistry, The Queen's University of Belfast, Belfast BT9 7BL, United Kingdom
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Marks NJ, Sangster NC, Maule AG, Halton DW, Thompson DP, Geary TG, Shaw C. Structural characterisation and pharmacology of KHEYLRFamide (AF2) and KSAYMRFamide (PF3/AF8) from Haemonchus contortus. Mol Biochem Parasitol 1999; 100:185-94. [PMID: 10391380 DOI: 10.1016/s0166-6851(99)00057-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The FMRFamide-related peptides (FaRPs), KHEYLRFamide (AF2) and KSAYMRFamide (PF3) were structurally characterised from the parasitic nematode of sheep, Haemonchus contortus (MH isolate). Both peptides were sequenced in a single gas-phase sequencing run and their structure confirmed by mass spectrometry which identified peptides of 920 Da (C-terminally amidated AF2) and 902/918 Da (C-terminally amidated non-oxidised/oxidised PF3, respectively). AF2 had inhibitory effects on H. contortus muscle and inhibited acetylcholine (ACh, 10 microM)-induced contractions, with a threshold for activity of 1 microM. PF3 induced concentration-dependent contractions of H. contortus (activity threshold, 10 nM) and enhanced ACh contractions. Compared with the MH isolate, an isolate of H. contortus which has reduced sensitivity to cholinergic drugs (Lawes isolate) was less sensitive to the effects of PF3. The concentration-response curves for the cholinergic compounds ACh and levamisole (LEV), and PF3, but not a control, KPNFIRFamide (PF4), showed a statistically similar shift. This study implicates PF3 in the modulation of cholinergic function in H. contortus.
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Affiliation(s)
- N J Marks
- Parasitology Research Group, The Queen's University of Belfast, UK.
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Marks NJ, Maule AG, Li C, Nelson LS, Thompson DP, Alexander-Bowman S, Geary TG, Halton DW, Verhaert P, Shaw C. Isolation, pharmacology and gene organization of KPSFVRFamide: a neuropeptide from Caenorhabditis elegans. Biochem Biophys Res Commun 1999; 254:222-30. [PMID: 9920762 DOI: 10.1006/bbrc.1998.9920] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To date, 53 peptides with C-terminal RFamides have been identified by the genome sequencing project in the nematode, Caenorhabditis elegans. In this study the FMRFamide-related peptide (FaRP) KPSFVRFamide (879.90 Da [MH]+) was structurally characterized from extracts of the nematode, Caenorhabditis elegans. Two copies of KPSFVRFamide are encoded by a gene designated flp-9. RT-PCR identified a single cDNA product which was confirmed as flp-9 by sequence determination. Flp-9 cDNA was isolated from larval stages of C. elegans but was not detected in adult worms, indicating that its expression is may be developmentally regulated. KPSFVRFamide displays sequence homology to the nematode peptide, KPNFIRFamide (PF4). The physiological effects of KPSFVRFamide, PF4 and the chimeras, KPNFVRFamide and KPSFIRFamide, were measured on body wall muscle and the vagina vera of the parasitic nematode, Ascaris suum. KPNFVRFamide and KPNFIRFamide had Cl--dependent inhibitory activity on innervated and denervated muscle-preparations, whereas KPSFVRFamide and KPSFIRFamide did not elicit a detectable physiological effect. Although all 4 peptides had inhibitory effects on the vagina vera, KPSFVRFamide and KPSFIRFamide (threshold, >/=0.1 microM) were less potent than KPNFVRFamide and KPNFIRFamide (threshold, >/=10 nM).
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, Queen's University of Belfast, Belfast, BT9 7BL, Northern
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Marks NJ, Maule AG, Geary TG, Thompson DP, Li C, Halton DW, Shaw C. KSAYMRFamide (PF3/AF8) is present in the free-living nematode, Caenorhabditis elegans. Biochem Biophys Res Commun 1998; 248:422-5. [PMID: 9675153 DOI: 10.1006/bbrc.1998.8982] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To date, seven FMRFamide-related peptides (FaRPs) have been structurally characterized from C. elegans, of which one is structurally identical to the parasitic nematode peptide AF2 (KHEYLRFamide). The other six FaRPs have so far been identified in free-living forms only. In the present study an additional FaRP was isolated and structurally characterized from an ethanolic extract of C. elegans. The extract was screened using a C-terminally directed FaRP antiserum, and the FMRFamide-immunoreactive peptide purified to homogeneity using HPLC. Approximately 80 pmol of the peptide was subjected to Edman degradation and the unequivocal primary structure of the K7-amide, KSAYMRFamide (PF3/AF8) was determined following a single gas-phase sequencing run. The molecular mass of the peptide was determined using a MALDI-TOF mass spectrometer and was found to be 919 (MH+), which is in agreement with the theoretical mass of C-terminally amidated PF3. A new flp-gene, designated flp-6, has recently been identified which encodes six copies of KSAYMRFamide (PF3/AF8).
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, The Queen's University of Belfast, Belfast, BT9 7BL, Northern Ireland, United Kingdom.
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Fellowes RA, Maule AG, Marks NJ, Geary TG, Thompson DP, Shaw C, Halton DW. Modulation of the motility of the vagina vera of Ascaris suum in vitro by FMRF amide-related peptides. Parasitology 1998; 116 ( Pt 3):277-87. [PMID: 9550221 DOI: 10.1017/s0031182097002229] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Ascaris suum contains a large number of FMRFamide-related peptides (FaRPs) of which KNEFIRFamide (AF1), KHEYLRFamide (AF2) and KSAYMRFamide (AF8, also called PF3) have been extensively studied and are known to exert actions on somatic muscle strips of the worm. In the present study, the effects of AF1, AF2 and AF8 on the activity of the vagina vera of female A. suum have been examined in vitro. The vagina vera is a muscular tube connecting the uterus and vagina uteri to the gonopore and is probably involved in regulating egg output. The tissue exhibited spontaneous, rhythmic contractions in vitro, which were modulated by each of the FaRPs tested. The effects of each of the peptides were qualitatively and quantitatively different, and in each case were reversible. AF1 (1 microM) caused a biphasic response in the form of a transient lengthening of the preparation, followed by a shortening; contractions were initially inhibited but resumed 5 min post-addition of the peptide. Lower concentrations (< or = 0.1 microM) induced a less marked effect, with rhythmic contractions returning 5 min post-addition. AF2 and AF8 reduced contraction frequency at concentrations > or = 0.1 microM. Both peptides also caused the tissue to shorten, although the effects of AF8 on baseline tension were inconsistent. The apparent potencies of AF1 and AF8 on contraction frequency of the vagina vera were 10-fold greater than AF2 and, unlike their actions on A. suum somatic body wall muscles, the actions of AF1 and AF2 were qualitatively different. Indeed, the effects of each of these FaRPs on the vagina vera were markedly different from those observed on the somatic muscle.
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Affiliation(s)
- R A Fellowes
- Comparative Neuroendocrinology Research Group, The Schools of Biology and Biochemistry and Clinical Medicine, The Queen's University of Belfast, UK
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Marks NJ, Maule AG, Halton DW, Geary TG, Shaw C, Thompson DP. Pharmacological effects of nematode FMRFamide-related peptides (FaRPs) on muscle contractility of the trematode, Fasciola hepatica. Parasitology 1997; 114 ( Pt 6):531-9. [PMID: 9172424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The physiological effects of synthetic replicates of the nematode FaRPs, AF1 (KNEFIRFamide), AF2 (KHEYLRFamide), PF1 (SDPNFLRFamide), PF2 (SADPNFLRFamide), AF8/PF3 (KSAYMRFamide) and PF4 (KPNFIRFamide) were examined on muscle preparations of the liver fluke, Fasciola hepatica. Changes in contractility following the addition of the test compound were recorded using a photo-optic transducer system. Unlike the varied effects these peptides have on nematode somatic musculature, all were found to induce excitatory responses in the muscle activity of F. hepatica. While qualitative effects of the nematode peptides were similar in that they induced increases in both the amplitude and frequency of F. hepatica muscle contractions, they varied considerably in the potency of their excitatory effects. The threshold activity for each peptide was as follows: 10 microM, PF1 and PF2; 3 microM, AF1 and PF3; 1 microM, AF2; and 30 nM, PF4. The results demonstrate, for the first time, the cross-phyla activity of nematode neuropeptides on the neuromuscular activity of a trematode.
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Affiliation(s)
- N J Marks
- Pharmacia & Upjohn Co., Kalamazoo, Michigan 49001, USA
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Marks NJ, Maule AG, Geary TG, Thompson DP, Davis JP, Halton DW, Verhaert P, Shaw C. APEASPFIRFamide, a novel FMRFamide-related decapeptide from Caenorhabditis elegans: structure and myoactivity. Biochem Biophys Res Commun 1997; 231:591-5. [PMID: 9070852 DOI: 10.1006/bbrc.1997.6155] [Citation(s) in RCA: 36] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
To date, 9 FMRFamide-related peptides (FaRPs) have been identified in Caenorhabditis elegans. Eight of these peptides are encoded on the flp-1 gene. However, AF2 (KHEYLRFamide) which was not co-encoded was the most abundant FaRP identified in ethanolic extracts. Further radioimmunometrical screening of acidified ethanol extracts of C. elegans has revealed the presence of other novel FaRPs, which are not encoded on the flp-1 gene. One of these peptides has been isolated by sequential rpHPLC and subjected to Edman degradation analysis and gas-phase sequencing and the unequivocal primary structure of the decapeptide Ala-Pro-Glu-Ala-Ser-Pro-Phe-Ile-Arg-Phe-NH2 was determined following a single gas-phase sequencing run. The molecular mass of the peptide was found to be 1133.7 Da, determined using a time-of-flight mass spectrometer. Synthetic replicates of this peptide were found to induce a profound relaxation of both dorsal and ventral somatic muscle-strip preparations of Ascaris suum with a threshold for activity of 10 nM. The inhibitory response was not dependent on the presence of nerve cords, indicating a post-synaptic site-of-action. The relaxation was Ca(+2)- and Cl(-)-independent but was abolished in high-K+ medium and could be distinguished from those of other inhibitory nematode FaRPs, including PF1 (SDPNFLRFamide) and PF4 (KPNFIRFamide).
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, Queen's University of Belfast, Northern Ireland
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Cable J, Marks NJ, Halton DW, Shaw C, Johnston CF, Tinsley RC, Gannicott AM. Cholinergic, serotoninergic and peptidergic components of the nervous system of Discocotyle sagittata (Monogenea:Polyopisthocotylea). Int J Parasitol 1996; 26:1357-67. [PMID: 9024885 DOI: 10.1016/s0020-7519(96)00130-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Cholinergic, serotoninergic (5-HT) and peptidergic neuronal pathways have been demonstrated in both central and peripheral nervous systems of adult Discocotyle sagittata, using enzyme histochemistry and indirect immunocytochemistry in conjunction with confocal scanning laser microscopy. Antisera to 2 native flatworm neuropeptides, neuropeptide F and the FMRFamide-related peptide (FaRP), GNFFRFamide, were employed to detect peptide immunoreactivity. The CNS is composed of paired cerebral ganglia and connecting dorsal commissure, together with several paired longitudinal nerve cords. The main longitudinal nerve cords (lateral, ventral and dorsal) are interconnected at intervals by a series of annular cross-connectives, producing a ladder-like arrangement typical of the platyhelminth nervous system. At the level of the haptor, the ventral cords provide nerve roots which innervate each of the 9 clamps. Cholinergic and peptidergic neuronal organisation was similar, but distinct from that of the serotoninergic components. The PNS and reproductive system are predominantly innervated by peptidergic neurones.
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Affiliation(s)
- J Cable
- School of Biological Sciences, University of Bristol, UK.
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Maule AG, Geary TG, Marks NJ, Bowman JW, Friedman AR, Thompson DP. Nematode FMRFamide-related peptide (FaRP)-systems: occurrence, distribution and physiology. Int J Parasitol 1996; 26:927-36. [PMID: 8923140 DOI: 10.1016/s0020-7519(96)80066-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The application of rational (mechanism-based) approaches to anthelmintic discovery requires information about target proteins which are pharmacologically distinguishable from their vertebrate homologs. In helminths, several such targets (e.g., beta-tubulin, ATP-generating enzymes, cholinergic receptors, CI- channels) have been characterized only after the discovery, through empirical screening, of compounds that interfere with their function. From the perspective of anthelmintic discovery, the utility of these targets is diminishing due to the emergence of drug-resistant strains of parasites. This has motivated the search for compounds with novel modes-of-action. Recent basic research in helminth physiology and biochemistry has identified several potential targets for rational anthelmintic discovery, including receptors for FMRFamide-related peptides (FaRPs). To date, over 20 different nematode FaRPs have been identified and these peptides, which are broadly distributed in helminths, have been localized to all of the major neuronal subtypes in nematodes. The FaRPs that have been examined have been found profoundly to affect somatic muscle function in gastrointestinal nematodes. In this respect, complex inhibitory and excitatory actions have been identified for a number of these peptides. Although the transduction pathways for any of these peptides remain to be elucidated, the available evidence indicates that nematode FaRPs have numerous mechanisms of action. The employment of nematode neuropeptide receptors in mechanism-based screens has immense potential in the identification of novel anthelmintics.
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Affiliation(s)
- A G Maule
- Upjohn Company, Kalamazoo, MI 49001, USA.
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Ryan RM, Whittet HB, Norval C, Marks NJ. Minimal follow-up after functional endoscopic sinus surgery. Does it affect outcome? Rhinology 1996; 34:44-5. [PMID: 8739870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
One disadvantage of functional endoscopic sinus surgery is the frequent post-operative cavity toilet considered necessary by most surgeons, which is not only costly but also very unwelcome to patients. In the Royal Berkshire Hospital in Reading, we have reviewed a series of 120 patients who underwent FESS over an 18-month period with minimal post-operative follow-up (first visit for cavity toilet at 2 weeks and, if possible, only one further visit) in order to assess outcome. The percentage of patients whose presenting symptom had significantly improved or was cured was 78%, and the mean number of follow-up visits was 2.8. We conclude that our policy of minimal post-operative follow-up following FESS allows results comparable with other series, and this policy should be further evaluated.
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Affiliation(s)
- R M Ryan
- Royal Berkshire Hospital, Reading, United Kingdom
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Maule AG, Bowman JW, Thompson DP, Marks NJ, Friedman AR, Geary TG. FMRFamide-related peptides (FaRPs) in nematodes: occurrence and neuromuscular physiology. Parasitology 1996; 113 Suppl:S119-35. [PMID: 9051931 DOI: 10.1017/s0031182000077933] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The occurrence of classical neurotransmitter molecules and numerous peptidic messenger molecules in nematode nervous systems indicate that although structurally simple, nematode nervous systems are chemically complex. Thus far, studies on one nematode neuropeptide family, namely the FMRFamide-related peptides (FaRPs), have revealed an unexpected variety of neuropeptide structures in both free-living and parasitic species. To date 23 nematode FaRPs have been structurally characterized including 12 from Ascaris suum, 8 from Caenorhabditis elegans, 5 from Panagrellus redivivus and 1 from Haemonchus contortus. Ten FaRP-encoding genes have been identified in Caenorhabditis elegans. However, the full complement of nematode neuronal messengers has yet to be described and unidentified nematode FaRPs await detection. Preliminary characterization of the actions of nematode neuropeptides on the somatic musculature and neurones of A, suum has revealed that these peptidic messengers have potent and complex effects. Identified complexities include the biphasic effects of KNEFIRFamide/KHEYLRFamide (AF1/2; relaxation of tone followed by oscillatory contractile activity) and KPNFIRFamide (PF4; rapid relaxation of tone followed by an increase in tone), the diverse actions of KSAYMRFamide (AF8 or PF3; relaxes dorsal muscles and contracts ventral muscles) and the apparent coupling of the relaxatory effects of SDPNFLRFamide/SADPNFLRFamide (PF1/PF2) to nitric oxide release. Indeed, all of the nematode FaRPs which have been tested on somatic muscle strips of A. suum have actions which are clearly physiologically distinguishable. Although we are a very long way from understanding how the actions of these peptides are co-ordinated, not only with those of each other but also with those of the classical transmitter molecules, to control nematode behaviour, their abundance coupled with their diversity of structure and function indicates a hitherto unidentified sophistication to nematode neuromuscular intergration.
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Affiliation(s)
- A G Maule
- Comparative Neuroendocrinology Research Group, School of Biology and Biochemistry and Clinical Medicine, Queen's University of Belfast, Northern Ireland
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Kubiak TM, Maule AG, Marks NJ, Martin RA, Wiest JR. Importance of the proline residue to the functional activity and metabolic stability of the nematode FMRFamide-related peptide, KPNFIRFamide (PF4). Peptides 1996; 17:1267-77. [PMID: 8971918 DOI: 10.1016/s0196-9781(96)00197-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PF4 has previously been shown to have potent inhibitory effects on myoactivity of somatic muscle strips from the nematode. Ascaris suum. This study examined the bioactivity and metabolic stability of position 2- and position 5-modified analogues of PF4. Although the analogues [Leu5]PF4,[Ala2]PF4, [Gly2]PF4, [Ala2,Leu5]PF4, and [Gly2,Leu5]PF4 all had qualitatively similar inhibitory effects on A. suum somatic muscle strips, their effects were quantitatively distinguishable and had the order of potency: PF4 = [Leu5]PF4 > > [Ala2]PF4 = [Ala2,Leu5]PF4 > > [Gly2]PF4 = [Gly2,Leu5]PF4, Leu5 for Ile5 substitutions in PF4 did not alter the activity of this peptide: however, Gly2/Ala2 for Pro2 substitutions reduced, but did not abolish, peptide activity. Peptide stability studies revealed that [Gly2]PF4(2-7) and -(3-7) and [Ala2]PF4(2-7), -(3-7), and -(4-7) fragments were generated following exposure to A. suum somatic muscle strips. However, the parent peptide (PF4) was not metabolized and appeared to be resistant to the sequential cleavages of native aminopeptidases. Observed analogue metabolism appeared to be due to the activity of released aminopeptidases as identical fragments were generated by incubation in medium that had been exposed to somatic muscle strips and from which the strips had been removed prior to peptide addition. It was found that the muscle stretching and bath mixing characteristics of the tension assay led to more effective release of soluble enzymes from muscle strips and thus greater peptide degradation. These studies reveal that Pro2 in PF4 is not essential for the biological activity of this peptide; however, it does render the peptide resistant to the actions of native nematode aminopeptidases.
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Affiliation(s)
- T M Kubiak
- Animal Health Discovery Research, Pharmacia & Upjohn, Inc., Kalmazoo, MI 49001, USA.
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Koay CB, Marks NJ. A nurse-led preadmission clinic for elective ENT surgery: the first 8 months. Ann R Coll Surg Engl 1996; 78:15-9. [PMID: 8659966 PMCID: PMC2502675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
A nurse-led preadmission clinic was set up in the Department of Otolaryngology of The Royal Berkshire Hospital, Reading, for patients undergoing elective ENT surgery. The progress of the clinic has been monitored during its first 8 months of service. A two-part study was undertaken: (a) A prospective study of the process from the time an admission appointment was sent until completion of surgery and, (b) a retrospective review of the case notes to study the quality of clerking and note keeping and the pattern of requests for investigations made by the nurses. In all, 514 patients were invited to attend the preadmission clinic before operation. Of these patients, 454 attended the clinic for preadmission clerking, 440 (96.9%) of whom underwent their operation without complication. All clerking notes were well kept, but a number of unnecessary investigations were requested. It is concluded that a nurse-led preadmission clinic is effective in the management of elective ENT operating lists. It assists in improving the quality of an SHO's training by reducing time spent on service commitments, thereby increasing the potential training time. More guidance to nurses on the use of preoperative investigations is needed.
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Affiliation(s)
- C B Koay
- Department of Otolaryngology, Royal Berkshire Hospital, Reading
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29
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Marks NJ, Shaw C, Maule AG, Davis JP, Halton DW, Verhaert P, Geary TG, Thompson DP. Isolation of AF2 (KHEYLRFamide) from Caenorhabditis elegans: evidence for the presence of more than one FMRFamide-related peptide-encoding gene. Biochem Biophys Res Commun 1995; 217:845-51. [PMID: 8554607 DOI: 10.1006/bbrc.1995.2849] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Numerous FMRFamide-related peptides (FaRPs) have been isolated and sequenced from extracts of free-living and parasitic nematodes. The most abundant FaRP identified in ethanolic/methanolic extracts of the parasitic forms, Ascaris suum and Haemonchus contortus and from the free-living nematode, Panagrellus redivivus, was KHEYLRFamide (AF2). Analysis of the nucleotide sequences of cloned FaRP-precursor genes from C. elegans and, more recently, Caenorhabditis vulgaris identified a series of related FaRPs which did not include AF2. An acid-ethanol extract of Caenorhabditis elegans was screened radioimmunometrically for the presence of FaRPs using a C-terminally directed FaRP antiserum. Approximately 300 pmols of the most abundant immunoreactive peptide was purified to homogeneity and 30 pmols was subjected to Edman degradation analysis and gas-phase sequencing. The unequivocal primary structure of the heptapeptide, Lys-His-Glu-Tyr-Leu-Arg-Phe-NH2 (AF2) was determined following a single gas-phase sequencing run. The molecular mass of the peptide was determined using a time-of-flight mass spectrometer and was found to be 920 (MH+)+, which was consistent with the theoretical mass of C-terminally amidated AF2. These results indicate that C. elegans possesses more than one FaRP gene.
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, Queen's University of Belfast, Northern Ireland
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30
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Kim E, Day TA, Marks NJ, Johnston RN, Halton DW, Shaw C, Chen GZ, Bennett JL, Pax RA. Immunohistochemical localization of a Shaker-related voltage-gated potassium channel protein in Schistosoma mansoni (Trematoda: Digenea). Exp Parasitol 1995; 81:421-9. [PMID: 8542982 DOI: 10.1006/expr.1995.1134] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We have recently isolated a cDNA (SKv1.1) encoding a Shaker-related K+ channel from the human parasitic trematode Schistosoma mansoni. In order to better understand the functions of SKv1.1 protein, the distribution of SKv1.1 protein in adult S. mansoni was analyzed by immunohistochemistry using a region-specific antibody. SKv1.1 proteins were widely expressed in the nervous and muscular systems. The strongest immunoreactivity (IR) was observed in the nervous system of both male and female. In the nervous system, IR for SKv1.1 proteins was localized in cell bodies and nerve fibers of the anterior ganglia, the central commissure, and the main nerve cords. IR was also observed in the dorsal and the ventral peripheral nerve nets, fine nerve fibers entering into a variety of structures such as the dorsal tubercles, longitudinal and ventral muscle fibers, and oral and ventral suckers. In the muscular system, SKv1.1 proteins were localized to the longitudinal, circular, and ventral muscle fibers of male as well as in isolated muscle fibers where native A-type K+ currents were measured. Moderate IR was also seen in a large number of cell bodies in the parenchyma. These results indicate that SKv1.1 protein may play an important role in the regulation of the excitability of neurons and muscle cells of S. mansoni.
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Affiliation(s)
- E Kim
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing 48824, USA
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Maule AG, Geary TG, Bowman JW, Marks NJ, Blair KL, Halton DW, Shaw C, Thompson DP. Inhibitory effects of nematode FMRFamide-related peptides (FaRPs) on muscle strips from Ascaris suum. Invert Neurosci 1995; 1:255-65. [PMID: 9372147 DOI: 10.1007/bf02211027] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A large number of FMRFamide-related peptides (FaRPs) are found in nematodes, and some of these are known to influence tension and contractility of neuromuscular strips isolated from Ascaris suum body wall. Relaxation of these strips has been noted with five nematode FaRPs. The inhibitory actions of SDPNFLRFamide (PF1) and SADPNFLRFamide (PF2) appear to be mediated by nitric oxide, as previously demonstrated with inhibitors of nitric oxide synthase (NOS). This present study showed that the effects of PF1 were also depended on external Ca++ and were reduced by the Ca(++)-channel blocker verapamil, observations consistent with the finding that nematode NOS is Ca(++)-dependent. KSAYMRFamide (PF3), KNIRFamide (PF4) and KNAFIRFamide (an alanine substituted analog of KNEFIRFamide, AF1, termed A3AF1) also relaxed A. suum muscle strips, but these responses were not affected by NOS inhibitors. PF3 inhibited the activity of strips prepared from the dorsal side of the worm, but contracted ventral strips. Both effects were dependent on the presence of ventral/dorsal nerve cords (unlike PF1/PF2) and were attenuated in medium which contained high K+ or low Ca++. PF4-induced muscle relaxation and hyperpolarization were independent of nerve cords, but were reversed in Cl-free medium, unlike PF1 or PF3. The PF4 effect physiologically desensitized muscle strips to subsequent treatment with PF4 and/or GABA. However, PF4 and GABA were not synergistic in this preparation. The effects of GABA, but not PF4, were reduced in muscle strips treated with the GABA antagonist, NCS 281-93. Following PF4 (or GABA) relaxation, subsequent treatment with higher doses of PF4 caused muscle strip contraction. A3AF1 was found to relax muscle strips and hyperpolarize muscle cells independently of the ventral and dorsal nerve cords, K+, Ca++, and Cl-, and mimicked the inhibitory phase associated with the exposure of these strips to AF1. On the basis of anatomical and ionic dependence, these data have delineated at least four distinct inhibitory activities attributable to nematode FaRPs. Clearly, a remarkably complex set of inhibitory mechanisms operate in the nematode neuromuscular system.
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Affiliation(s)
- A G Maule
- Upjohn Company, Kalamazoo, MI 49001, USA
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Abstract
We report the results of a prospective pilot study of 54 adult patients undergoing tonsillectomy using the KTP-532 laser, designed to assess whether the technique would facilitate day-case adult tonsillectomy. Subjective and objective assessment at six hours post-operatively showed that only 43 per cent could, in our judgement, have been discharged at this interval. Furthermore, the overall complication rate was 31 per cent with a secondary haemorrhage rate of 19 per cent. We conclude that KTP-532 laser tonsillectomy as performed in this pilot study compares unfavourably with dissection tonsillectomy and we discuss possible reasons for this.
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Affiliation(s)
- N M Raine
- Department of Otolaryngology, Royal Berkshire Hospital, Reading
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Marks NJ, Halton DW, Maule AG, Brennan GP, Shaw C, Southgate VR, Johnston CF. Comparative analyses of the neuropeptide F (NPF)- and FMRFamide-related peptide (FaRP)-immunoreactivities in Fasciola hepatica and Schistosoma spp. Parasitology 1995; 110 ( Pt 4):371-81. [PMID: 7753578 DOI: 10.1017/s0031182000064714] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Immunochemical techniques were used to determine the distribution, chemical characteristics and relative abundance of immunoreactivity (IR) to two native platyhelminth neuropeptides, neuropeptide F (NPF) (Moniezia expansa) and the FMRFamide-related peptide (FaRP), GNFFRFamide, in the trematodes, Fasciola hepatica and Schistosoma mansoni; the larger S. margrebowiei was used in the chemical analysis. Extensive immunostaining for the two peptides was demonstrated throughout the nervous systems of both F. hepatica and S. mansoni, with strong IR also in the innervation of muscular structures, including those associated with the egg-forming apparatus. The patterns of immunostaining were similar to those previously described for the vertebrate neuropeptide Y superfamily of peptides and for FMRFamide. Ultrastructurally, gold labelling of NPF- and GNFFRFamide-IRs was localized exclusively to the contents of secretory vesicles in the axons and somatic cytoplasm of neurones. Double-labelling experiments showed an apparent homogeneity of antigenic sites, in all probability due to the demonstrated cross-reactivity of the FaRP antiserum with NPF. Radioimmunoassay of acid-ethanol extracts of the worms detected 8.3 pmol/g and 4.7 pmol/g equivalents of NPF- and FMRFamide-IRs, respectively, for F. hepatica, and corresponding values of 4.9 pmol/g and 4.3 pmol/g equivalents for S. margrebowiei. Gel-permeation chromatography resolved IR to both peptides in discrete peaks and these eluted in similar positions to synthetic NPF (M. expansa) and GNFFRFamide, respectively.
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, Queen's University of Belfast, UK
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Abstract
5-HT-immunoreactivity in Entobdella soleae was found to be extensive throughout both the central and peripheral nervous systems, with the strongest staining occurring in the innervation of the forebody, most notably in the paired cerebral ganglia, pharynx and adhesive pads. In the reproductive system, staining was evident throughout the numerous cell bodies and fibres innervating the musculature of the egg-assembly apparatus. The haptor contained an extensive array of serotoninergic fibres derived from the main longitudinal cords; this array was associated with the haptoral muscles and sclerites, and possibly with the ventral sensory papillae.
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, School of Biology, Queen's University of Belfast, U.K
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35
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Abstract
Chicken (avian) pancreatic polypeptide was the first member of the pancreatic polypeptide (PP)/neuropeptide Y (NPY) superfamily to be discovered and structurally-characterised. In this 36 amino acid residue, C-terminally amidated peptide, residues 22 and 23 were identified as Asp and Asn, respectively. However, sequencing of chicken PP using modem automated gas-phase sequencing technology has revealed that the original primary structure is incorrect in that residue 22 is Asn and that residue 23 is Asp. After digestion of chicken PP with endoproteinase Asp-N, fragments of chicken PP corresponding in molecular mass to residues 16-22 and 23-36, were unequivocally identified. The corrected primary structure of chicken PP is therefore: Gly-Pro-Ser-Gln-Pro-Thr-Tyr-Pro-Gly-Asp-Asp- Ala-Pro-Val-Glu-Asp-Leu-Ile-Arg- Phe-Tyr-Asn-Asp-Leu-Gln-Gln-Tyr-Leu-Asn-Val-Val-Thr-Arg-His-Arg-Tyr-NH2.
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, Queen's University of Belfast, UK
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36
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Abstract
1. In almost all studies involving localization or quantitation of regulatory peptides, an essential prerequisite is the generation of specific antisera in rabbits. Despite this almost universal practice, the primary structures of some established regulatory peptides, such as pancreatic polypeptide (PP), of the rabbit, remain unknown. 2. Here we report the full primary structure of PP isolated from extracts of rabbit pancreas. 3. PP immunoreactivity was purified using an antiserum (PP 221) generated to the highly-conserved C-terminal hexapeptide amide of mammalian PP. A single molecular form of rabbit PP was consistently resolved during sequential chromatographic fractionations. 4. Automated Edman degradation established the full primary structure as: APPEPVYPGDDATPEQMAEYVADLRRYINMLTRPRY. The molecular mass derived from this sequence (4196.7 Da), was in full agreement with that determined by mass spectroscopy (4196 Da). The peptide was deemed to be C-terminally amidated due to its full molar crossreactivity with the amide-requiring PP antiserum employed. 5. When compared with all other known mammalian PP sequences, rabbit PP displays three unique substituted sites, Pro at position 3, Glu at position 19 and Val at position 21.
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Affiliation(s)
- N J Marks
- School of Clinical Medicine, Queen's University of Belfast, Northern Ireland
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Marks NJ, Shaw C, Halton DW, Maule AG, Curry WJ, Verhaert P, Thim L. Isolation and primary structure of a novel avian pancreatic polypeptide from five species of Eurasian crow. Regul Pept 1993; 47:187-94. [PMID: 8234905 DOI: 10.1016/0167-0115(93)90423-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Chicken pancreatic polypeptide is the prototype of the neuropeptide Y (NPY)/PP superfamily of regulatory peptides. This polypeptide was appended the descriptive term avian, despite the presence of some 8600 extant species of bird. Additional primary structures from other avian species, including turkey, goose and ostrich, would suggest that the primary structure of this polypeptide has been highly-conserved during avian evolution. Avian pancreatic polypeptides structurally-characterised to date have distinctive primary structural features unique to this vertebrate group including an N-terminal glycyl residue and a histidyl residue at position 34. The crow family, Corvidae, is representative of the order Passeriformes, generally regarded as the most evolutionarily recent and diverse avian taxon. Pancreatic polypeptide has been isolated from pancreatic tissues from five representative Eurasian species (the magpie, Pica pica; the jay, Garrulus glandarius; the hooded crow, Corvus corone; the rook, Corvus frugilegus; the jackdaw, Corvus monedula) and subjected to structural analyses. Mass spectroscopy estimated the molecular mass of each peptide as 4166 +/- 2 Da. The entire primary structures of 36 amino acid residue peptides were established in single gas-phase sequencing runs. The primary structures of pancreatic polypeptides from all species investigated were identical: APAQPAYPGDDAPVEDLLRFYNDLQQYLNVVTRPRY. The peptides were deemed to be amidated due to their full molar cross-reactivity with the amide-requiring PP antiserum employed. The molecular mass (4165.6 Da), calculated from the sequences, was in close agreement with mass spectroscopy estimates. The presence of an N-terminal alanyl residue and a prolyl residue at position 34 differentiates crow PP from counterparts in other avian species.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, School of Clinical Medicine, Queen's University of Belfast, UK
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Marks NJ, Shaw C, Halton DW, Thim L. The primary structure of pancreatic polypeptide from a primitive insectivorous mammal, the European hedgehog (Erinaceous europaeus). Regul Pept 1993; 47:179-85. [PMID: 8234904 DOI: 10.1016/0167-0115(93)90422-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Pancreatic polypeptide (PP) has been isolated from extracts of the pancreas of the European hedgehog (Erinaceous europaeus) which is a representative of the order Insectivora, deemed to be the most primitive group of placental mammals. Pancreatic tissues were extracted in acidified ethanol and the peptide was purified chromatographically using a PP C-terminal hexapeptide amide specific radioimmunoassay to monitor purification. Two major PP-immunoreactive peptides were baseline-resolved following the final analytical reverse phase HPLC fractionation. Each was separately subjected to plasma desorption mass spectroscopy (PDMS) and gas-phase sequencing. The molecular masses of each peptide were similar: (I) 4237.6 +/- 4 Da and (II) 4238.2 +/- 4 Da. The full primary structures of each peptide were deduced and these were identical: VPLEPVYPGDNATPEQMAHYAAELRRYINMLTRPRY. The peptides were deemed to be amidated due to their full molar cross-reactivity with the amide-requiring PP antiserum employed in radioimmunoassay. The molecular mass (4233.8 Da) calculated from the sequence was in close agreement with PDMS estimates and the reason for the different retention times of each peptide is unknown at present. Hedgehog PP exhibits only 2 unique amino acid substitutions, at positions 1 (Val) and 19 (His), when compared with other mammalian analogues.
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, School of Clinical Medicine, Queen's University of Belfast, UK
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Abstract
The localization and distribution of cholinergic, serotoninergic and peptidergic nerve elements in the proteocephalidean tapeworm, Proteocephalus pollanicola, have been investigated by enzyme histochemistry, and by an indirect immunofluorescence technique interfaced with confocal scanning laser microscopy. Cholinesterase (ChE) activity was localized in the major components of the central nervous system (CNS) and the peripheral nervous system (PNS), including the innervation of the reproductive structures of the worm. Serotoninergic (5-HT) nerves were found in the paired cerebral ganglia, transverse commissure and in the 10 longitudinal nerve cords. Antisera to 17 mammalian regulatory peptides and the invertebrate peptide FMRFamide have been used to explore the peptidergic nervous system of the worm. The most extensive immunostaining occurred with antisera raised to members of the neuropeptide Y superfamily, namely neuropeptide Y (NPY), peptide YY (PYY) and pancreatic polypeptide (PP). In all cases, intense immunoreactivity was found in numerous cell bodies and fibres of both the CNS and PNS, including the innervation of the reproductive apparatus. FMRFamide antisera stained the same structures to a comparable degree as those raised to the NPY superfamily. Cholinergic and peptidergic elements were much more prevalent within the CNS, while the serotoninergic nerve fibres tended to dominate in the PNS. The overlap obtained in staining patterns for the peptidergic and cholinergic components suggests that there may be a certain amount of co-localization of peptides with small-molecule transmitter substances in the same neurone. Weak staining for the tachykinin, substance P and for calcitonin gene-related peptide (CGRP) was confined to the major longitudinal nerve cords.
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, School of Biology & Biochemistry, Queen's University of Belfast, Northern Ireland, U.K
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Marks NJ, Maule AG, Halton DW, Shaw C, Johnston CF. Distribution and immunochemical characteristics of neuropeptide F (NPF) (Moniezia expansa) - immunoreactivity in Proteocephalus pollanicola (Cestoda: Proteocephalidea). Comp Biochem Physiol C Comp Pharmacol Toxicol 1993; 104:381-6. [PMID: 8103428 DOI: 10.1016/0742-8413(93)90004-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
1. Using immunocytochemical techniques and confocal scanning laser microscopy, the proteocephalidean cestode, Proteocephalus pollanicola from Lough Neagh pollan (Coregomus autumnalis) was examined for the presence of the native platyhelminth neuropeptide, neuropeptide F (NPF). 2. An antiserum specific for whole-molecule NPF (1-39) (Moniezia expansa) did not immunostain nerve processes in P. pollanicola. A C-terminally-directed NPF (30-39) (M. expansa) antiserum immunostained nerve fibres and cell bodies of both the central and peripheral nervous systems, including innervation associated with the female reproductive system. 3. The pattern of immunoreactivity was identical to that obtained using antisera to the C-terminal region of mammalian NPY-superfamily peptides and the invertebrate neuropeptide, FMRFamide. 4. Under radioimmunoassay conditions, only the C-terminally-directed NPF antiserum cross-reacted with the P. pollanicola peptide and detected 58.74 ng/g wet weight of NPF-1 R in extracts of the worm. 5. Chromatographic characterisation of P. pollanicola NPF-immunoreactivity indicated an apparent molecular weight of 4400-4700 Da, similar to that of NPF (M. expansa). 6. Further analytical HPLC characterisation identified two molecular forms of P. pallanicoda NPF-immunoreactivity, both of which had different retention times from those of NPF (M. expansa) and NPF (Artioposthia triangulata). 7. These data suggest that P. pollanicola possesses a neuropeptide which is homologous in its C-terminal region to NPF (M. expansa) but differs in its mid- to N-terminal region.
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Affiliation(s)
- N J Marks
- Comparative Neuroendocrinology Research Group, Schools of Biology and Biochemistry and Clinical Medicine, Queen's University of Belfast, UK
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Abstract
The results of turbinate reduction surgery carried out on 307 patients are reviewed. This is a retrospective study over 16 years. The results of submucosal diathermy with and without outfracture, partial inferior turbinectomy and linear cautery were all equally disappointing in the long term. At 1 month postoperatively the overall success rate, as defined by patient satisfaction, was 82%, but this declined steadily with time to 60% at 3 months, 54% at 1 year and 41% at 1-16 years. There was no significant difference found in the success rates between methods of turbinate reduction used. These findings are compared with more optimistic reports in the literature and their relevance to current surgical practice is discussed.
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Marks NJ, Emery P, Onisiphorou C. A Controlled Trial of Acupuncture in Tinnitus. Acupunct Med 1986. [DOI: 10.1136/aim.3.1.19] [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: 11/04/2022]
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45
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Abstract
The design and use of the levator scapulae flap is reviewed. Particular attention is paid to the blood flow. A description is given of how this flap may be employed to repair smaller defects of the mouth and pharynx. It is used in association with split skin. The use of such a technique is compared to musculo-cutaneous flaps, with particular reference to the skin blood flow.
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Abstract
Two experiments carried out on rat skin flaps are described, where microvascular flow has been measured noninvasively by a laser Doppler velocimeter. Using this technique it is possible to define the limits of an axial pattern flap in terms of microvascular flow; this was found to increase when the flap is elevated. 'Random-pattern' perfusion is defined by a fall in flow. This recovers sequentially along the flap, and at a constant rate at all sites. A differential in microvascular perfusion is thus maintained along a random-pattern flap for at least the first postoperative week. In a second experiment it is shown that there appears to be a linear relationship between the reduction in skin blood flow in a random-pattern flap and the distance from the base at which the measurements are made. It is suggested that these data support the view that the blood flow in a skin flap recovers primarily from its base rather than via peripheral neovascularization, and that this is due to vascular collaterals opening within the flap rather than to a relaxation of sympathetic tone.
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47
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Abstract
A group of 14 patients with unilateral tinnitus were selected because of the constant nature of their tinnitus, and its resistance to all other forms of therapy. They were subjected to hypnosis in three forms in random order. The induction of a trance state alone formed the control arm of the trial. Compared to this were the effects of 'ego boosting' and active suppression of tinnitus whilst in a trance state. One of the 14 patients showed a highly significant response to the latter treatment as judged by visual analogue scales. Five of the 14 patients (36%) found the induction of a hypnotic state of value. This seemed to help them tolerate their tinnitus better, although its loudness and quality were unaltered.
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48
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49
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Abstract
The relationship of tinnitus to pain is examined and a theoretical case made out for the possible use of acupuncture in the treatment of tinnitus. A double-blind cross-over controlled trial is described. The use of Visual Analogue Scales (V.A.S.) is discussed in this context. 35 per cent of patients described some benefit from the active treatment only, although we were unable to demonstrate this objectively. Statistical analysis of the group as a whole revealed no significant differences between placebo and active acupuncture treatment.
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50
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Abstract
A series of 17 parotid glands were obtained by radical parotidectomy. Between 1 and 11 lymph nodes were found in them. Superficial parotidectomy only leaves an average of 1 node in the deep parotid. There is a 1 in 4 chance of there being no nodes left. There were no nodes easily accessible immediately under the deep part of the parotid gland. There seems to be a discrepancy between the number of nodes found in a radical surgical specimen and serial sections of the area. This suggests a significant number may be left in the skin flap. The place of excision of this skin is discussed.
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