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Autonomic dysreflexia is a common complication after high level spinal cord injury and can be life-threatening. We have previously shown that the acute transplantation of olfactory ensheathing cells into the lesion site of rats transected at the fourth thoracic spinal cord level reduced autonomic dysreflexia up to 8weeks after spinal cord injury. This beneficial effect was correlated with changes in the morphology of sympathetic preganglionic neurons despite the olfactory cells surviving no longer than 3weeks. Thus the transitory presence of olfactory ensheathing cells at the injury site initiated long-term functional as well as morphological changes in the sympathetic preganglionic neurons. The primary aim of the present study was to evaluate whether olfactory ensheathing cells survive after transplantation within the parenchyma close to sympathetic preganglionic neurons and whether, in this position, they still reduce the duration of autonomic dysreflexia and modulate sympathetic preganglionic neuron morphology. The second aim was to quantify the density of synapses on the somata of sympathetic preganglionic neurons with the hypothesis that the reduction of autonomic dysreflexia requires synaptic changes. As a third aim, we evaluated the cell type-specificity of olfactory ensheathing cells by comparing their effects with a control group transplanted with fibroblasts. Animals transplanted with OECs had a faster recovery from hypertension induced by colorectal distension at 6 and 7weeks but not at 8weeks after T4 spinal cord transection. Olfactory ensheathing cells survived for at least 8weeks and were observed adjacent to sympathetic preganglionic neurons whose overall number of primary dendrites was reduced and the synaptic density on the somata increased, both caudal to the lesion site. Our results showed a long term cell type-specific effects of olfactory ensheathing cells on sympathetic preganglionic neurons morphology and on the synaptic density on their somat

The immune response contributes to ongoing secondary tissue destruction following spinal cord injury (SCI). Although infiltrating neutrophils and monocytes have been well studied in this process, T-cells have received less attention. The objective of this study was to assess locomotor recovery and tissue morphology after SCI in athymic (nude) rats, in which T-cell numbers are reduced. Results in athymic rats were compared with heterozygote littermates with normal T-cell profiles and with Sprague-Dawley rats from previous studies in our lab. Following transection of rat spinal cords at T10, we assessed the animals' locomotor recovery on a weekly basis for up to 11 weeks, using the Basso-Beattie-Bresnahan locomotor rating scale. Nude rats showed better locomotor recovery than did heterozygote or Sprague-Dawley rats, achieving scores of 5.6 ± 0.8 versus 1.0 ± 0.0, respectively (p = 0.002), at 4 weeks postinjury. The improved recovery of nude rats persisted for the 11-week postinjury assessment period, and was consistent with improved spinal reflexes rather than with recovery of descending motor pathways. Anatomical evaluation at 11 weeks indicated no difference in nude versus heterozygote rats in the size or distribution of cavities caudal to the transection site, but secondary damage was more severe rostral to the transection site in heterozygote rats. In neither group did cavities extend beyond 4 mm caudal to the transection site, and were therefore not directly responsible for the functional differences between the two groups. Cellular expression of the microglia/macrophage antigen ectodysplasin A (ED1) was reduced in nude rats as compared to heterozygotes, but no difference was observed in expression levels of 5-hydrosytryptamine, the 200-kDa neurofilament, or glial fibrillary acidic protein. The findings of the study show that a reduction in T-cell numbers significantly improves locomotor recovery after spinal cord transection, indicating a deleterious role for th

This study used the extrauterine development of a marsupial wallaby to investigate the onset of functional activity in the somatosensory pathway from the whiskers. In vivo recordings were made from the somatosensory cortex from postnatal day (P) 55 to P138, in response to electrical stimulation of the infraorbital nerve supplying the mystacial whiskers. Current source density analysis was used to localize the responses within the cortical depth. This was correlated with development of cortical lamination and the onset of whisker-related patches, as revealed by cytochrome oxidase. The earliest evoked activity occurred at P61, when layers 5 and 6 are present, but layer 4 has not yet developed. This activity showed no polarity reversal with depth, suggesting activity in thalamocortical afferents. By P72 synaptic responses were detected in developing layer 4 and cytochrome oxidase showed the first hint of segregation into whisker-related patches. These patches were clear by P86. The evoked response at this age showed synaptic activity first in layer 4 and then in deep layer 5/upper layer 6. With maturity, responses became longer lasting with a complex sequence of synaptic activity at different cortical depths. The onset of functional activity is coincident with development of layer 4 and the onset of whisker-related pattern formation. A similar coincidence is seen in the rat, despite the markedly different chronological timetable, suggesting similar developmental mechanisms may operate in both species.

The work consists of reports compiled at the request of the Department of Trade and Industry in the late 1960s and completed in 1971, with subsequent additions made until the author's death in 1987. For each mine the map reference, grid reference and deposited plan number (when one exists) are given, the current state of the workings and their known extent, production and ore grades are described, the most recent exploration work and its results are discussed and suggestions are made as to the most promising lines of investigation for the future. Six potential tin mining areas in west Cornwall are: Wheal Hermon; the Carnelloe Consols and Dollar mines; the mines of Trink Hill (Giew and Wheal Reath); the mines of the Marazion copper district (Owen Vean, Tregurtha Downs, Wheal Hampton, Wheal Rodney and Wheal Virgin); Wheal Vor; and the shallow workings between Wheal Osborne and Wheal Susan. Eight areas of potential in central Cornwall are: the Great Flat Lode district (Wheal Uny and the eastern Great Flat Lode); the Redruth-Scorrier copper-tin district (Wheal Boys, Wheal Prussia, Cardrew, Cardrew Consols, Wheal Montague, Wheal Harmony, Treleigh Wood, Wheal Peevor and West Wheal Peevor); Killifreth and Great Wheal Busy; Stencoose and Wheal Concord; the north coast for a mile west of Porthtowan; Wheal Coates; Wheal Kitty and West Wheal Kitty at St Agnes; and south Gwennap. East Cornwall has potential for other metals in the lead and zinc mining district between Newquay and Truro (Lambriggan, Wheal Alfred and Shepherds) and the Castle-an-Dinas wolfram mine near St Columb, with the main tin potential in the former copper district around St Austell, Par and St Blazey (Par Consols and West Fowey Consols). Photographs are included of most of the mines when last working., The work consists of reports compiled at the request of the Department of Trade and Industry in the late 1960s and completed in 1971, with subsequent additions made until the author's death in 1987. For each mine the map reference, grid reference and deposited plan number (when one exists) are given, the current state of the workings and their known extent, production and ore grades are described, the most recent exploration work and its results are discussed and suggestions are made as to the most promising lines of investigation for the future. Six potential tin mining areas in west Cornwall are: Wheal Hermon; the Carnelloe Consols and Dollar mines; the mines of Trink Hill (Giew and Wheal Reath); the mines of the Marazion copper district (Owen Vean, Tregurtha Downs, Wheal Hampton, Wheal Rodney and Wheal Virgin); Wheal Vor; and the shallow workings between Wheal Osborne and Wheal Susan. Eight areas of potential in central Cornwall are: the Great Flat Lode district (Wheal Uny and the eastern Great Flat Lode); the Redruth-Scorrier copper-tin district (Wheal Boys, Wheal Prussia, Cardrew, Cardrew Consols, Wheal Montague, Wheal Harmony, Treleigh Wood, Wheal Peevor and West Wheal Peevor); Killifreth and Great Wheal Busy; Stencoose and Wheal Concord; the north coast for a mile west of Porthtowan; Wheal Coates; Wheal Kitty and West Wheal Kitty at St Agnes; and south Gwennap. East Cornwall has potential for other metals in the lead and zinc mining district between Newquay and Truro (Lambriggan, Wheal Alfred and Shepherds) and the Castle-an-Dinas wolfram mine near St Columb, with the main tin potential in the former copper district around St Austell, Par and St Blazey (Par Consols and West Fowey Consols). Photographs are included of most of the mines when last working.

Details are given of ouput, ownership, management and employment at several mines in the Flintshire and Denbighshire areas. The north east Wales orefield consisted of a relatively small and compact area of alternating series of carboniferous limestone and Cefn-yfedw sandstone series, roughly delineated by Abergele, Llangollen and Flint. During the 1845-1913 period most of the lead/silver/zinc output came from an even smaller area, measuring less than 18 miles by 8 from Holywell to Minera, lying along the county boundary itself. The district produced around 10% of the UK's lead between 1845 and 1885, but as the revived Flintshire mines came on stream from the late 1880s, this share climbed to between 15 to 30% and remained on that high level until 1913. The mines in the area were among the first to exploit zinc ore commercially and in 1868 it accounted for almost half of the UK's output., Details are given of ouput, ownership, management and employment at several mines in the Flintshire and Denbighshire areas. The north east Wales orefield consisted of a relatively small and compact area of alternating series of carboniferous limestone and Cefn-yfedw sandstone series, roughly delineated by Abergele, Llangollen and Flint. During the 1845-1913 period most of the lead/silver/zinc output came from an even smaller area, measuring less than 18 miles by 8 from Holywell to Minera, lying along the county boundary itself. The district produced around 10% of the UK's lead between 1845 and 1885, but as the revived Flintshire mines came on stream from the late 1880s, this share climbed to between 15 to 30% and remained on that high level until 1913. The mines in the area were among the first to exploit zinc ore commercially and in 1868 it accounted for almost half of the UK's output.

This is the ninth volume in the continuing series of The Mineral Statistics of the United Kingdom 1845-1913. It completes the coverage of the major English non-ferrous mining districts and continues that for Central Wales. Drawing on official government records, details are provided of the output, ownership, management and employment at over 250 mines. Ordnance Survey grid references have been added to provide a guide to the mines' location and their often still impressive remains. The counties covered by this volume include some of the oldest and largest of the mining sites in Britain and stand witness to a once thriving but now totally defunct industry., This is the ninth volume in the continuing series of The Mineral Statistics of the United Kingdom 1845-1913. It completes the coverage of the major English non-ferrous mining districts and continues that for Central Wales. Drawing on official government records, details are provided of the output, ownership, management and employment at over 250 mines. Ordnance Survey grid references have been added to provide a guide to the mines' location and their often still impressive remains. The counties covered by this volume include some of the oldest and largest of the mining sites in Britain and stand witness to a once thriving but now totally defunct industry.

The returns for the metal mines of Derbyshire are presented, reconstituted in a mine-by-mine format for 1845 to the beginning of the first world war. The data are presented in the same form as they appear in the returns, with a minimum of editorial adjustment., The returns for the metal mines of Derbyshire are presented, reconstituted in a mine-by-mine format for 1845 to the beginning of the first world war. The data are presented in the same form as they appear in the returns, with a minimum of editorial adjustment.

Material from the annual volumes of the Mineral Statistics of the United Kindom is reproduced in this book in a mine-by-mine format with minimum editing. Mine names are uncorrected and multiple returns listed separately but locations are amended and Ordinance Survey grid references given for current usage. Information on output, ownership, management and employment for the many lead, zinc and iron mines of the county is given. Production data is given by type of mineral and often includes ore output, metal content, and value. Employment, ownership and management returns are drawn from the list of mines., Material from the annual volumes of the Mineral Statistics of the United Kindom is reproduced in this book in a mine-by-mine format with minimum editing. Mine names are uncorrected and multiple returns listed separately but locations are amended and Ordinance Survey grid references given for current usage. Information on output, ownership, management and employment for the many lead, zinc and iron mines of the county is given. Production data is given by type of mineral and often includes ore output, metal content, and value. Employment, ownership and management returns are drawn from the list of mines.

It includes references to around 500 books, 100 university theses and nearly 2 000 articles drawn from over 300 different journals and periodicals. It is arranged on a regional basis and there are sections for all of the major mining districts of England, Wales, Scotland and the Isle of Man., It includes references to around 500 books, 100 university theses and nearly 2 000 articles drawn from over 300 different journals and periodicals. It is arranged on a regional basis and there are sections for all of the major mining districts of England, Wales, Scotland and the Isle of Man.

A compilation of statistics originally published in 'The mineral statistics of the United Kingdom' listing all metalliferous mines operating in Devon and Somerset during the period with the reported production for each year. Details of owners and managers are also given where available., A compilation of statistics originally published in 'The mineral statistics of the United Kingdom' listing all metalliferous mines operating in Devon and Somerset during the period with the reported production for each year. Details of owners and managers are also given where available.

A summary of the "Mineral statistics of the United Kingdom" for mines in Cornwall for 1845-1913 is reprinted. A detailed list is given of 1 500 mining ventures, with figures for production of tin, copper and other ores, ownership and management., A summary of the "Mineral statistics of the United Kingdom" for mines in Cornwall for 1845-1913 is reprinted. A detailed list is given of 1 500 mining ventures, with figures for production of tin, copper and other ores, ownership and management.

The volume presents a comprehensive survey of the production, ownership, management and employment of all the metal mines working in the district from the mid-nineteenth century to the First World War., The volume presents a comprehensive survey of the production, ownership, management and employment of all the metal mines working in the district from the mid-nineteenth century to the First World War.

The volume contains a comprehensive survey of the production, ownership, management and employment of lead, iron and other metal mines from the mid-nineteenth century to the First World War., The volume contains a comprehensive survey of the production, ownership, management and employment of lead, iron and other metal mines from the mid-nineteenth century to the First World War.

The book covers the southern half of the central Wales orefield and provides details of the output, ownership, management and employment of more than 250 mines operating in the county from the mid-nineteenth century. Some of these mines were among the most important in the British Isles, producing large quantities of silver as well as lead and zinc ore., The book covers the southern half of the central Wales orefield and provides details of the output, ownership, management and employment of more than 250 mines operating in the county from the mid-nineteenth century. Some of these mines were among the most important in the British Isles, producing large quantities of silver as well as lead and zinc ore.