Macroinvertebrate communities are strongly influenced by hydrological variability in surface wate... more Macroinvertebrate communities are strongly influenced by hydrological variability in surface waters. However, the response of these communities in corresponding groundwater-dependent habitats is not well understood. This study characterised the macroinvertebrate fauna and physicochemical characteristics of a chalk aquifer and its river in southern England. Samples were collected over one year from three perennial and two temporary paired benthic-hyporheic sites and seven phreatic sites in the surrounding aquifer. The study was preceded by a period of below average rainfall, providing an opportunity to assess the response of macroinvertebrate communities to unseasonal declines in river discharge and groundwater levels. Benthic, hyporheic and phreatic habitats each supported a distinct macroinvertebrate community, with the hyporheic habitat supporting both epigean taxa and stygofauna. As discharge declined, the composition of these communities changed. In particular, the abundance of the epigean amphipod Gammarus pulex was higher in hyporheic than benthic habitats during periods of low surface discharge, suggesting potential refuge-seeking behaviour. Similarly, fluctuations in the abundance and distribution of two stygofauna, Crangonyx subterraneus and Niphargus fontanus, coincided with marked changes in groundwater levels, suggesting that the contraction of available habitat and changes in connectivity also influenced the phreatic community. The variable distribution of macroinvertebrates between these habitats, especially in response to hydrological variability, suggests a dynamic connection between the river and its aquifer. This connection is an important consideration for the assessment and conservation management of both surface and groundwater communities and may help to underpin integrated, catchment-based environmental management, especially in river systems with temporary reaches.
L. Uisge: carbonaceous particle profile L. Uisge: variation of major ion concentrations with sedi... more L. Uisge: carbonaceous particle profile L. Uisge: variation of major ion concentrations with sediment depth L. Uisge: variation of trace metal concentrations with sediment depth L. Uisge: relationships between zinc and sodium and lead and sodium concentrations in the sediments L. Teanga: bathymetry L. Teanga: lithostratigraphy L. Teanga: 210 Pb chronology L. Teanga: diatom summary diagram and pH reconstructions L. Teanga: diatom pH preference groups L. Teanga: diatom concentration L. Teanga: summary pollen diagram L. Teanga: carbonaceous particle profile L. Teanga: ash sphere concentration profile L. Teanga: variation of major ion concentrations with sediment depth L. Teanga: variation of trace metal concentrations with sediment depth L. Teanga: relationships between zinc and sodium and lead and sodium concentrations in the sediments Acknowledgements 47 48 49 This paper was prepared as part of a research programme sponsored by the Department of the Environment. Water chemistry analyses were performed at the SOAFD Laboratory,
cc ep te d A rt ic le This article has been accepted for publication and undergone full peer revi... more cc ep te d A rt ic le This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1111/1365-2745.12195 This article is protected by copyright. All rights reserved.
Project co-funded by the European Commission within the Sixth Framework Programme (2002-2006) Dis... more Project co-funded by the European Commission within the Sixth Framework Programme (2002-2006) Dissemination Level (tick appropriate box) PU Public PP Restricted to other programme participants (including the Commission Services) RE Restricted to a group specified by the consortium (including the Commission Services) CO Confidential, only for members of the consortium (including the Commission Services)
Spatial and temporal variability in periphytic diatom communities: Palaeoecological significance ... more Spatial and temporal variability in periphytic diatom communities: Palaeoecological significance in an acidified lake. VJ Jones, RJ Flower 1986. Spatial and temporal variations in the epipsammic and epilithic diatom communities ...
In a review of work on 10 of the very numerous lakes of the English Lake District work which invo... more In a review of work on 10 of the very numerous lakes of the English Lake District work which involved co-operation between palaeolimnologists from different disciplines and between palaeoand neolimnologists the questions asked by the researchers are listed and it is shown which kind of lake has provided constructive answers. Complete and conformable sediment profiles covering the last ca 14000 years are found in these lakes, but no single profile is optimal for study of the whole period. Knowledge of the pattern of sediment accumulation is necessary before the record in microfossils and changing sediment composition can be interpreted with confidence. The demonstration that the sedimentsource material of these open lakes must have been largely allochthonous established the importance of the sediment column as a record of changes through time in the composition and stability of the soils of each catchment. These changes illustrate the influence of: 1. Climatic changes, from glacial to temperate interstadial followed by renewed glaciation (Younger Dryas) and then by a long temperate (postglacial) state, during which changes in stream run-off and in the pattern of deposition in lakes indicate changes in precipitation and wind-induced turbulence. 11. Processes of pedogenesis, determining the composition of sediment-source material. iii. Changes in aquatic and terrestrial biota in response to climatic changes interacting with biological processes; the major changes which coincide with changing land use by man over 5000 years, and the more recent changes associated with the dates for human discharges into lakes and the deposition of airborne pollutants.
Western blotting and densitometry have been used to investigate the lipocortin content of post-mo... more Western blotting and densitometry have been used to investigate the lipocortin content of post-mortem central nervous system (CNS) tissue samples from multiple sclerosis (MS) patients and normal controls. Lipocortins 1, 2, 4 and 5 were all detected in normal control grey and white matter. In white matter samples from MS patients these lipocortins were found to be significantly increased, a further elevation in lipocortin content was observed in MS plaque tissue. The implications of these findings with respect to the role of these proteins in inflammatory CNS disease and a possible mechanism of steroid action in the therapy of MS are discussed.
I first heard of Ed Deevey in 1950, when I was a beginning Ph.D. student at Yale. I came from a t... more I first heard of Ed Deevey in 1950, when I was a beginning Ph.D. student at Yale. I came from a three-person biology department whose minuscule library did not include the American Journal of Science, in which Ed had published his most important work. I had, however, been poking around the lakes and bogs of Nova Scotia for five years and was full of half-formed ideas about paleolimnology, climatic change, and the relevance of past climate to the modern distribution of plants and animals. I was chagrined to find a man I had never heard of, an American at that, who’d had all the same ideas ten years before, formulated them more clearly and carried out the work with an ingenuity and completeness beyond my aspirations. For a few weeks I was afraid to read another Deevey paper, and when the man himself returned from Yucatan I became his first graduate student.
Lipocortins are structurally related, glucocorticoid-inducible proteins that inhibit phopholipase... more Lipocortins are structurally related, glucocorticoid-inducible proteins that inhibit phopholipase A2 (PLA2), thereby reducing the liberation of arachidonic acid from phospholipids and so limiting the synthesis of eicosanoid inflammatory mediators. This study is the first demonstration of one lipocortin, lipocortin 1 (Lc 1; 37 kDa), inhuman lunglavage supernatants. In lavage fluid from healthy volunteers, a higher percentage (> 70 %) ofthe detected Lc 1 was in its native form, compared to that from patients with abnormal lungs. In patients' lavage fluids, Lc 1 was more likely to be partially degraded (34 kDa). In abnormal bronchoalveolar lavage fluid (BALF), the more polymorphonuclear neutrophils (PMN)/lavage, the lower the proportion of Lc 1 in the native (37 kDa) form (n = 7 pairs, rs =-0.8214, p < 0.05). Furthermore, when BALF cells were cultured and the harvested conditioned media incubated with pure human recombinant Lc 1, degradation of the 37 kDa form increased with the percentage of PMN (n = 10 pairs, s =-0.7200 after 1 hr; n = 6 pairs, rs =-0.9241 after 6 hr). These results suggest that factors released from the PMN are responsible for Lc 1 degradation in man. When recombinant human Lc 1 was incubated with human neutrophil elastase, the enzyme degraded Lc 1 in a dose-dependent way, suggesting that neutrophil elastase may be one such factor. Since PMNs are ubiquitous at sites of inflammation, it is possible that Lc 1 degradation is a permissive mechanism, which ensures that sufficient inflammation occurs to destroy the provocative stimulus. However, it is equally possible that, in some circumstances, the mechanism may be pathological and that the inactivation of Lc 1 leads to chronic, uncontrolled inflammation.
Hydrocortisone inhibits prostaglandin generation by rat peritoneal leucocytes by releasing the po... more Hydrocortisone inhibits prostaglandin generation by rat peritoneal leucocytes by releasing the polypeptide phospholipase inhibitor, macrocortin. The susceptibility of these cells to hydrocortisone is directly correlated with their intracellular macrocortin content. Cells depleted of the peptide by prior incubation with steroid cannot respond to the steroid, until a fresh intracellular store has been synthesized. In vitro, this process requires 4-5 h. Cells remain sensitive to the inhibitory action of the peptide at all times.
The effect of topical betamethasone upon skin blood flow was investigated in the rat. Two types o... more The effect of topical betamethasone upon skin blood flow was investigated in the rat. Two types of vasodilator stimuli were used; local heating to the surface of the skin and intradermal application of inflammatory agents. Blood flow was measured by laser doppler velocimetry. 2 Topical betamethasone-17-valerate (1 g with an 18 h pretreatment) significantly inhibited the heatinduced vasodilatation in the rat skin, as also did systemically administered betamethasone (1 mg kg-, 3 h pretreatment). 3 Angiotensin converting enzyme (ACE) inhibitors (captopril, 5 mg kg-' and enalapril, I mg kg-', 30 min pretreatments) were the only drugs out of several different types of systemically administered inhibitors and antagonists that were tested which also inhibited the heat-induced vasodilatation. Aprotinin (100,000 KIU kg-', 5 min pretreatment) a serine protease inhibitor, significantly potentiated the heat-induced response. 4 Bradykinin (50 nmol per site), des-Arg9-bradykinin (5 nmol per site), substance P (0.1 nmol per site) and capsaicin (1 jtmol per site) induced an increase in skin blood flow. 5 Topical betamethasone treatment resulted in a significant inhibition of the vasodilator response to des-Arg9-bradykinin, whereas captopril treatment inhibited the responses to substance P. capsaicin, bradykinin and des-Arg9-bradykinin. 6 Intradermal application of captopril (10-100pg) also caused a dose-dependent inhibition of the heat-induced vasodilatation. 7 These results suggest that topical betamethasone may be acting in a manner similar to that of the ACE inhibitors to produce an inhibition of the flow responses in the skin and that this effect may be brought about by interfering with the action of vasodilator peptide(s) or protein(s).
Natterjack toads Bufo calamita have declined sharply at heathland sites in Britain during the 20t... more Natterjack toads Bufo calamita have declined sharply at heathland sites in Britain during the 20th century. A significant feature of these habitats is the predominance of oligotrophic and dystrophic ponds on substrates with low buffering capacities. Acid ponds at one site, Woolmer Forest, were classified into two groups: shallow pools dominated by Sphagnum and high concentrations of organic solutes, and larger bodies of water in which pH was primarily influenced by inorganic anions (especially S04). Pond pHs responded transiently to episodes of very acid (pH < 4) rain, but acidity in the larger ponds was probably modulated mainly by mobilisation of sulphur accumulated in sedimentary peat over many decades. Rain was significantly acidified (on average about threefold) after passage through pine canopies, but this effect was not observed after percolation through birch foliage. Two large ponds previously used but deserted by natterjacks within the last 50
Macroinvertebrate communities are strongly influenced by hydrological variability in surface wate... more Macroinvertebrate communities are strongly influenced by hydrological variability in surface waters. However, the response of these communities in corresponding groundwater-dependent habitats is not well understood. This study characterised the macroinvertebrate fauna and physicochemical characteristics of a chalk aquifer and its river in southern England. Samples were collected over one year from three perennial and two temporary paired benthic-hyporheic sites and seven phreatic sites in the surrounding aquifer. The study was preceded by a period of below average rainfall, providing an opportunity to assess the response of macroinvertebrate communities to unseasonal declines in river discharge and groundwater levels. Benthic, hyporheic and phreatic habitats each supported a distinct macroinvertebrate community, with the hyporheic habitat supporting both epigean taxa and stygofauna. As discharge declined, the composition of these communities changed. In particular, the abundance of the epigean amphipod Gammarus pulex was higher in hyporheic than benthic habitats during periods of low surface discharge, suggesting potential refuge-seeking behaviour. Similarly, fluctuations in the abundance and distribution of two stygofauna, Crangonyx subterraneus and Niphargus fontanus, coincided with marked changes in groundwater levels, suggesting that the contraction of available habitat and changes in connectivity also influenced the phreatic community. The variable distribution of macroinvertebrates between these habitats, especially in response to hydrological variability, suggests a dynamic connection between the river and its aquifer. This connection is an important consideration for the assessment and conservation management of both surface and groundwater communities and may help to underpin integrated, catchment-based environmental management, especially in river systems with temporary reaches.
L. Uisge: carbonaceous particle profile L. Uisge: variation of major ion concentrations with sedi... more L. Uisge: carbonaceous particle profile L. Uisge: variation of major ion concentrations with sediment depth L. Uisge: variation of trace metal concentrations with sediment depth L. Uisge: relationships between zinc and sodium and lead and sodium concentrations in the sediments L. Teanga: bathymetry L. Teanga: lithostratigraphy L. Teanga: 210 Pb chronology L. Teanga: diatom summary diagram and pH reconstructions L. Teanga: diatom pH preference groups L. Teanga: diatom concentration L. Teanga: summary pollen diagram L. Teanga: carbonaceous particle profile L. Teanga: ash sphere concentration profile L. Teanga: variation of major ion concentrations with sediment depth L. Teanga: variation of trace metal concentrations with sediment depth L. Teanga: relationships between zinc and sodium and lead and sodium concentrations in the sediments Acknowledgements 47 48 49 This paper was prepared as part of a research programme sponsored by the Department of the Environment. Water chemistry analyses were performed at the SOAFD Laboratory,
cc ep te d A rt ic le This article has been accepted for publication and undergone full peer revi... more cc ep te d A rt ic le This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1111/1365-2745.12195 This article is protected by copyright. All rights reserved.
Project co-funded by the European Commission within the Sixth Framework Programme (2002-2006) Dis... more Project co-funded by the European Commission within the Sixth Framework Programme (2002-2006) Dissemination Level (tick appropriate box) PU Public PP Restricted to other programme participants (including the Commission Services) RE Restricted to a group specified by the consortium (including the Commission Services) CO Confidential, only for members of the consortium (including the Commission Services)
Spatial and temporal variability in periphytic diatom communities: Palaeoecological significance ... more Spatial and temporal variability in periphytic diatom communities: Palaeoecological significance in an acidified lake. VJ Jones, RJ Flower 1986. Spatial and temporal variations in the epipsammic and epilithic diatom communities ...
In a review of work on 10 of the very numerous lakes of the English Lake District work which invo... more In a review of work on 10 of the very numerous lakes of the English Lake District work which involved co-operation between palaeolimnologists from different disciplines and between palaeoand neolimnologists the questions asked by the researchers are listed and it is shown which kind of lake has provided constructive answers. Complete and conformable sediment profiles covering the last ca 14000 years are found in these lakes, but no single profile is optimal for study of the whole period. Knowledge of the pattern of sediment accumulation is necessary before the record in microfossils and changing sediment composition can be interpreted with confidence. The demonstration that the sedimentsource material of these open lakes must have been largely allochthonous established the importance of the sediment column as a record of changes through time in the composition and stability of the soils of each catchment. These changes illustrate the influence of: 1. Climatic changes, from glacial to temperate interstadial followed by renewed glaciation (Younger Dryas) and then by a long temperate (postglacial) state, during which changes in stream run-off and in the pattern of deposition in lakes indicate changes in precipitation and wind-induced turbulence. 11. Processes of pedogenesis, determining the composition of sediment-source material. iii. Changes in aquatic and terrestrial biota in response to climatic changes interacting with biological processes; the major changes which coincide with changing land use by man over 5000 years, and the more recent changes associated with the dates for human discharges into lakes and the deposition of airborne pollutants.
Western blotting and densitometry have been used to investigate the lipocortin content of post-mo... more Western blotting and densitometry have been used to investigate the lipocortin content of post-mortem central nervous system (CNS) tissue samples from multiple sclerosis (MS) patients and normal controls. Lipocortins 1, 2, 4 and 5 were all detected in normal control grey and white matter. In white matter samples from MS patients these lipocortins were found to be significantly increased, a further elevation in lipocortin content was observed in MS plaque tissue. The implications of these findings with respect to the role of these proteins in inflammatory CNS disease and a possible mechanism of steroid action in the therapy of MS are discussed.
I first heard of Ed Deevey in 1950, when I was a beginning Ph.D. student at Yale. I came from a t... more I first heard of Ed Deevey in 1950, when I was a beginning Ph.D. student at Yale. I came from a three-person biology department whose minuscule library did not include the American Journal of Science, in which Ed had published his most important work. I had, however, been poking around the lakes and bogs of Nova Scotia for five years and was full of half-formed ideas about paleolimnology, climatic change, and the relevance of past climate to the modern distribution of plants and animals. I was chagrined to find a man I had never heard of, an American at that, who’d had all the same ideas ten years before, formulated them more clearly and carried out the work with an ingenuity and completeness beyond my aspirations. For a few weeks I was afraid to read another Deevey paper, and when the man himself returned from Yucatan I became his first graduate student.
Lipocortins are structurally related, glucocorticoid-inducible proteins that inhibit phopholipase... more Lipocortins are structurally related, glucocorticoid-inducible proteins that inhibit phopholipase A2 (PLA2), thereby reducing the liberation of arachidonic acid from phospholipids and so limiting the synthesis of eicosanoid inflammatory mediators. This study is the first demonstration of one lipocortin, lipocortin 1 (Lc 1; 37 kDa), inhuman lunglavage supernatants. In lavage fluid from healthy volunteers, a higher percentage (> 70 %) ofthe detected Lc 1 was in its native form, compared to that from patients with abnormal lungs. In patients' lavage fluids, Lc 1 was more likely to be partially degraded (34 kDa). In abnormal bronchoalveolar lavage fluid (BALF), the more polymorphonuclear neutrophils (PMN)/lavage, the lower the proportion of Lc 1 in the native (37 kDa) form (n = 7 pairs, rs =-0.8214, p < 0.05). Furthermore, when BALF cells were cultured and the harvested conditioned media incubated with pure human recombinant Lc 1, degradation of the 37 kDa form increased with the percentage of PMN (n = 10 pairs, s =-0.7200 after 1 hr; n = 6 pairs, rs =-0.9241 after 6 hr). These results suggest that factors released from the PMN are responsible for Lc 1 degradation in man. When recombinant human Lc 1 was incubated with human neutrophil elastase, the enzyme degraded Lc 1 in a dose-dependent way, suggesting that neutrophil elastase may be one such factor. Since PMNs are ubiquitous at sites of inflammation, it is possible that Lc 1 degradation is a permissive mechanism, which ensures that sufficient inflammation occurs to destroy the provocative stimulus. However, it is equally possible that, in some circumstances, the mechanism may be pathological and that the inactivation of Lc 1 leads to chronic, uncontrolled inflammation.
Hydrocortisone inhibits prostaglandin generation by rat peritoneal leucocytes by releasing the po... more Hydrocortisone inhibits prostaglandin generation by rat peritoneal leucocytes by releasing the polypeptide phospholipase inhibitor, macrocortin. The susceptibility of these cells to hydrocortisone is directly correlated with their intracellular macrocortin content. Cells depleted of the peptide by prior incubation with steroid cannot respond to the steroid, until a fresh intracellular store has been synthesized. In vitro, this process requires 4-5 h. Cells remain sensitive to the inhibitory action of the peptide at all times.
The effect of topical betamethasone upon skin blood flow was investigated in the rat. Two types o... more The effect of topical betamethasone upon skin blood flow was investigated in the rat. Two types of vasodilator stimuli were used; local heating to the surface of the skin and intradermal application of inflammatory agents. Blood flow was measured by laser doppler velocimetry. 2 Topical betamethasone-17-valerate (1 g with an 18 h pretreatment) significantly inhibited the heatinduced vasodilatation in the rat skin, as also did systemically administered betamethasone (1 mg kg-, 3 h pretreatment). 3 Angiotensin converting enzyme (ACE) inhibitors (captopril, 5 mg kg-' and enalapril, I mg kg-', 30 min pretreatments) were the only drugs out of several different types of systemically administered inhibitors and antagonists that were tested which also inhibited the heat-induced vasodilatation. Aprotinin (100,000 KIU kg-', 5 min pretreatment) a serine protease inhibitor, significantly potentiated the heat-induced response. 4 Bradykinin (50 nmol per site), des-Arg9-bradykinin (5 nmol per site), substance P (0.1 nmol per site) and capsaicin (1 jtmol per site) induced an increase in skin blood flow. 5 Topical betamethasone treatment resulted in a significant inhibition of the vasodilator response to des-Arg9-bradykinin, whereas captopril treatment inhibited the responses to substance P. capsaicin, bradykinin and des-Arg9-bradykinin. 6 Intradermal application of captopril (10-100pg) also caused a dose-dependent inhibition of the heat-induced vasodilatation. 7 These results suggest that topical betamethasone may be acting in a manner similar to that of the ACE inhibitors to produce an inhibition of the flow responses in the skin and that this effect may be brought about by interfering with the action of vasodilator peptide(s) or protein(s).
Natterjack toads Bufo calamita have declined sharply at heathland sites in Britain during the 20t... more Natterjack toads Bufo calamita have declined sharply at heathland sites in Britain during the 20th century. A significant feature of these habitats is the predominance of oligotrophic and dystrophic ponds on substrates with low buffering capacities. Acid ponds at one site, Woolmer Forest, were classified into two groups: shallow pools dominated by Sphagnum and high concentrations of organic solutes, and larger bodies of water in which pH was primarily influenced by inorganic anions (especially S04). Pond pHs responded transiently to episodes of very acid (pH < 4) rain, but acidity in the larger ponds was probably modulated mainly by mobilisation of sulphur accumulated in sedimentary peat over many decades. Rain was significantly acidified (on average about threefold) after passage through pine canopies, but this effect was not observed after percolation through birch foliage. Two large ponds previously used but deserted by natterjacks within the last 50
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