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Kroll JS, Farrant JL, Tyler S, Coulthart MB, Langford PR. Characterisation and genetic organisation of a 24-MDa plasmid from the Brazilian Purpuric Fever clone of Haemophilus influenzae biogroup aegyptius. Plasmid 2002; 48:38-48. [PMID: 12206754 DOI: 10.1016/s0147-619x(02)00020-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Strains of Haemophilus influenzae biogroup aegyptius causing septicaemia were identified in Brazil in the 1980s, causing the life-threatening illness of Brazilian Purpuric Fever (BPF). The strains were found to fall into a single clonal group, the BPF clone, characterised by their possession of the approximately 24MDa "3031" plasmid. In this work we report the characterisation and genetic organisation of this plasmid. Analysis of the gene content of what appears to be a typical broad host range conjugative plasmid, its presence in non-BPF strains as revealed by Southern hybridisation, and the recent discovery of plasmid-lacking BPF strains, has led us to conclude that it is unlikely to play a critical role in bacterial virulence. Establishing its entire sequence has nonetheless been an important step on the road to delineating, by comparison of BPF and non-BPF strains, chromosomal genetic loci that are involved in the special virulence of the BPF clone.
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Pfistermüller R, Tyler S. Correlation of fluorescence and electron microscopy of F-actin-containing sensory cells in the epidermis of Convoluta pulchra
(Platyhelminthes: Acoela). ACTA ZOOL-STOCKHOLM 2002. [DOI: 10.1046/j.1463-6395.2002.00095.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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28
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Zhou ZH, Han Y, Wei T, Aras S, Chaturvedi P, Tyler S, Rani MR, Ransohoff RM. Regulation of monocyte chemoattractant protein (MCP)-1 transcription by interferon-gamma (IFN-gamma) in human astrocytoma cells: postinduction refractory state of the gene, governed by its upstream elements. FASEB J 2001; 15:383-92. [PMID: 11156954 DOI: 10.1096/fj.00-0373com] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Monocyte chemoattractant protein (MCP)-1 is expressed by astrocytes in diverse inflammatory states and is a key regulator of monocyte recruitment to the central nervous system (CNS). In the current study, we addressed mechanisms by which transcription of the human MCP-1 gene (hMCP-1) was terminated, after induction by interferon (IFN)-gamma. Our results demonstrated that IFN-gamma-induced transcription of hMCP-1 was followed by a refractory state, during which hMCP-1 was resistant to restimulation by either IFN-gamma or heterologous activators such as TNF-alpha. This refractory state affected the hMCP-1 gene selectively, as other IFN-gamma-inducible genes remained responsive to restimulation. The IFN-gamma-induced hMCP-1 refractory state was governed at the transcriptional level and was sensitive to protein synthesis inhibitors, suggesting a requirement for newly expressed components. A minimal 213 base pair hMCP-1 regulatory element directed both IFN-gamma-mediated transcription and the subsequent refractory state. We previously demonstrated that IFN-gamma treatment resulted in coordinate protein occupancy in vivo of two hMCP-1 promoter elements, a gamma-activated site (GAS) and a GC-rich element. During the refractory state, IFN-gamma treatment failed to induce protection of either the hMCP-1 GAS element or the GC box. These results furnish insight into the expression of hMCP-1 during CNS inflammation and provide the first delineation of an IFN-gamma-induced transcriptional refractory state.
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Tyler S. The NHS plan. Plan puts patients first, but who will want to care for them? BMJ (CLINICAL RESEARCH ED.) 2000; 321:1015. [PMID: 11039977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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30
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Tyler S, Rieger RM. Functional morphology of musculature in the acoelomate worm, Convoluta pulchra (Plathelminthes). ZOOMORPHOLOGY 1999. [DOI: 10.1007/s004350050087] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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31
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Abstract
In an effort to understand how the feeding motions of Urastoma cyprinae are generated, the arrangement of its musculature was studied using fluorescence microscopy of phalloidin-linked fluorescent stains and conventional light histology and transmission electron microscopy. BODIPY 558/568 phalloidin and Alexa 488 phalloidin resolved a meshwork of ribbon-shaped body-wall muscles as well as inner-body musculature associated with the pharynx and male copulatory organ. The general pattern of body-wall muscles in U. cyprinae is similar to that of other rhabdocoel turbellarians in consisting only of circular, longitudinal, and diagonal fibers; the arrangement of these muscles readily correlates with the bending motions the animal undergoes as it feeds at the surface of gills in bivalves it parasitizes. The orogenital atrium of U. cyprinae lies at the posterior apex of the body, opening at a terminal pore. As evidenced by the arrangement of its epithelium and musculature, it appears to be an invagination of the body wall and comes closest of any such duct studied in turbellarians to satisfying the hypothetical model of a "pseudopharynx," ostensibly adapted as an organ for swallowing and so supplementing the ingestive role of the animal's true pharynx.
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Tyler S. Symbolic Heat: Gender, Health, and Worship among the Tamils of South India and Sri Lanka. Dennis B. McGilvray. JOURNAL OF ANTHROPOLOGICAL RESEARCH 1999. [DOI: 10.1086/jar.55.2.3631233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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33
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Marrie TJ, Tyler S, Bezanson G, Dendy C, Johnson W. Analysis of Legionella pneumophila serogroup 1 isolates by pulsed-field gel electrophoresis. J Clin Microbiol 1999; 37:251-4. [PMID: 9854106 PMCID: PMC84227 DOI: 10.1128/jcm.37.1.251-254.1999] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
At a hospital in Halifax, Nova Scotia, Canada, three strains of Legionella pneumophila were detectable based on plasmid content, while the isolates collected at another hospital in Halifax had no plasmids. Genomic DNA was digested with BssHII, SalI, and SpeI and subjected to pulsed-field gel electrophoresis (PFGE). We found no relationship between plasmid profile and PFGE pattern.
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Williams J, Chaloner J, Bean D, Tyler S. Coping with loss: the development and evaluation of a children's bereavement project. J Child Health Care 1998; 2:58-65. [PMID: 10474410 DOI: 10.1177/136749359800200202] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The 'Kingfisher Project' is a community-based programme of support groups for bereaved children. It has been developed by a multi-disciplinary group of workers from health, education, social services and the voluntary sector. Thirty-six children and young people have have been through the first five groups of the programme. Children accessing the service are predominantly those at high risk of developing longer-term problems as a result of bereavement. Evaluation indicates that the children and young people benefit in terms of increased social, behavioural, emotional and physical well-being. Two sub-groups appear to have benefited less: these are children and young people with learning difficulties, and teenage girls. Project evaluation has enabled workers to develop insights into the programme's strengths and weaknesses and has raised questions which merit further exploration.
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Allen SJ, MacGowan SH, Tyler S, Wilcock GK, Robertson AG, Holden PH, Smith SK, Dawbarn D. Reduced cholinergic function in normal and Alzheimer's disease brain is associated with apolipoprotein E4 genotype. Neurosci Lett 1997; 239:33-6. [PMID: 9547165 DOI: 10.1016/s0304-3940(97)00872-0] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Apolipoprotein E (ApoE) is a potent risk factor for Alzheimer's disease. Since the loss of cholinergic function in Alzheimer's disease is known to occur at an early stage in the disease we have examined this function in normal subjects with an Apoepsilon4 allele to see if the deficit occurs in the absence of Alzheimer pathology or symptoms. We report that brain tissue obtained post-mortem from normal subjects and Alzheimer patients with an Apoepsilon4 allele has a lower cholinergic activity than tissue from those subjects without this allele. This has important significance for the interpretation of the cholinergic deficits found in Alzheimer's disease.
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Tyler S. The 1997 legislature in review. NEVADA RNFORMATION 1997; 6:6-9. [PMID: 9416069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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37
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Holden PH, Asopa V, Robertson AG, Clarke AR, Tyler S, Bennett GS, Brain SD, Wilcock GK, Allen SJ, Smith SK, Dawbarn D. Immunoglobulin-like domains define the nerve growth factor binding site of the TrkA receptor. Nat Biotechnol 1997; 15:668-72. [PMID: 9219271 DOI: 10.1038/nbt0797-668] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Nerve growth factor (NGF) is involved in the development and maintenance of the nervous system. NGF binds with high affinity to the extracellular region of the tyrosine kinase receptor TrkA. This domain comprises leucine and cysteine rich motifs, followed by two immunoglobulin like (Ig-like) domains. We describe the expression and purification of recombinant Ig-like domains. Fluorescence and circular dichroism spectroscopy show that the protein is folded into a compact globular structure and contains mainly beta-sheet secondary structure. Recombinant protein binds to NGF and can inhibit NGF bioactivity both in vitro and in vivo.
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Abstract
The epidermis of members of the major parasitic taxon Neodermata is distinctive among flatworms, being a syncytial, insunk, non-ciliated epidermis that develops through a wholesale replacement of larval epidermis at metamorphosis when the larva attacks a host. How it arose in evolution from what must have been a turbellarian-like ancestor is not immediately evident. While many turbellarian flatworms have also adopted a symbiotic way of life, the literature on ultrastructure of epidermis in these symbionts shows quite a variety of morphologies, many not so different from that of their free-living relatives. Various turbellarians do have syncytial or insunk epidermises or reduction of epidermal ciliation as is characteristic of the Neodermata, but co-occurrence in a single turbellarian of all features common to neodermatans has not been reported. Urastoma cyprinae, for example, which is ectosymbiotic on bivalves, has a ciliated cellular epidermis that is little different from what is known of epidermises of its free-living relatives. The endoparasitic Anoplodium hymanae, from the coelom of sea cucumbers, also bears a ciliated cellular epidermis, as is typical of many other rhabdocoels, but it shows marked phagocytic activity as well as incorporation of endosymbiotic bacteria. The closest similarity to neodermatan epidermis is that of the turbellarian Genostoma kozloffi, an ectosymbiont of the crustacean Nebalia: covering the bulk of the body is a non-ciliated syncytium with multiple branching connections to insunk nucleated portions, much as in epidermis of adult neodermatans and, on its ventral surface, is a field of ciliated cellular insunk epidermis resembling the epidermis of some larval neodermatans. Developmental clues to the origin of the neodermatan epidermis can be seen in turbellarian embryos. Before hatching, embryos of proseriate and triclad embryos go through 3 generations of epidermis, each replacing the next; 2 generations of epidermis are reported in the literature on rhabdocoel embryos. This process of replacement parallels the epidermal replacement that larval neodermatans undergo at metamorphosis. Ultrastructural study of developing acoel, polyclad and macrostomid embryos shows that they, too, have epidermal replacement and growth through immigration of deeper-lying cells, comparable to the processes seen in higher flatworms. Succession of distinct generations of epidermis in such animals as the proseriates, triclads and rhabdocoels is probably an adaptation to development of ectolecithal eggs, providing the means for the embryo to use yolk that resides in vitellocytes, outside its blastomeres. We propose that the Neodermata has taken advantage of this developmental mechanism, producing successive generations of epidermal cells even in its larval stages, to counter the defenses of hosts.
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Tyler S. Catching up with vitamin K. MIDWIVES : OFFICIAL JOURNAL OF THE ROYAL COLLEGE OF MIDWIVES 1996; 109:273. [PMID: 8949138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Poirier V, Tyler S, Sleeman J, Diffin F, Brown K. Tumorigenicity associated with chromosome 11p15 alterations in sv40-transformed human kidney-cells. Int J Oncol 1995; 7:623-30. [PMID: 21552882 DOI: 10.3892/ijo.7.3.623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Chromosome 11p15 has been suggested to be a potential site for a second Wilms' tumour gene (a childhood nephroblastoma). Human foetal kidney cells and normal kidney cells from Wilms' tumour patients were transformed with SV40 derivative vectors. As some of the cell lines progressed to tumorigenicity, we observed that chromosome 11p13, site of the WT1 suppressor gene, did not show any allelic loss. However, RFLP analysis showed that chromosome 11p15 was affected by allelic losses on different genes in some cell lines but not necessarily prior to the appearance of tumorigenicity. We also observed that the most aggressive cell Line (SVCU/NK), derived from the normal kidney cells of a Wilms' tumour patient, showed increased expression of c-Ha-ras proto-oncogene at later passage and in the tumour tissue extracted from nude mice. Finally we report a lack of tumour suppression activity of one cell line SVT1B6/NK, when fused with the tumorigenic G401 cell line (the latter has been used in tumour suppression experiments as a Wilms' tumour cell line before being identified as a Rhabdoid tumour cell line). These experiments are consistent with the existence of a suppressor gene at chromosome 11p15.
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Ferguson P, Tyler S. "Voting for change". Report of the RCM annual conference, 1995--Belfast. MIDWIVES : OFFICIAL JOURNAL OF THE ROYAL COLLEGE OF MIDWIVES 1995; 108:290-3. [PMID: 7553127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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42
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Tyler S. Only plumbers? MODERN MIDWIFE 1995; 5:4. [PMID: 7780762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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43
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Singh V, Brockbank MJ, Frost RA, Tyler S. Multidisciplinary management of dysphagia: the first 100 cases. J Laryngol Otol 1995; 109:419-24. [PMID: 7797998 DOI: 10.1017/s0022215100130324] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A report of the first 100 patients treated in the multidisciplinary Dysphagia Clinic in Salisbury District Hospital is presented. It was established in January 1992 and involves the Departments of ENT Surgery, Clinical Radiology and Speech and Language Therapy. In the first 18 months, 100 patients have been assessed and treated. These included 46 males and 54 females, between the ages of four and 93 years. Neurological problems accounted for 39 cases. The management comprised the assessment clinic, videofluoroscopy in 83 patients, and finally the appropriate treatment. Forty-four patients were treated primarily by swallowing therapy. Seventy-three patients showed complete recovery, resolution of their symptoms or did not require treatment. Two patients were still under treatment at the time of writing this paper.
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Marrie TJ, Johnson W, Tyler S, Bezanson G, Haldane D, Burbridge S, Joly J. Potable water and nosocomial Legionnaires' disease--check water from all rooms in which patient has stayed. Epidemiol Infect 1995; 114:267-76. [PMID: 7705490 PMCID: PMC2271285 DOI: 10.1017/s0950268800057939] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We studied 7 patients with nosocomial Legionnaires' disease to determine the relationship between isolates of Legionella pneumophila recovered from potable water and those recovered from patients. Potable water was cultured from all rooms in which patients had stayed prior to the diagnosis of Legionnaires' disease. The 38 isolates of L. pneumophila (31 environmental, 7 patient) were resolved into 9 distinct patterns by pulse-field gel electrophoresis (PFGE), 3 by plasmid content and 2 each with monoclonal antibodies and conventional agarose gel electrophoresis of small fragments of DNA. Using PFGE it was determined that 4 of the 7 patients were infected with L. pneumophila identical to an isolate recovered from the potable water supply in one of the rooms each had occupied prior to the diagnosis of Legionnaires' disease. Patients had resided in a mean of 3.57 rooms before a diagnosis of nosocomial Legionnaires' disease. We conclude that in the setting of contaminated potable water and nosocomial Legionnaires' disease water from all the rooms which the patient has occupied prior to this diagnosis should be cultured. PFGE of large DNA fragments discriminated best among the isolates of L. pneumophila.
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Ferguson P, Tyler S. RCM Annual Conference 1994. MIDWIVES CHRONICLE 1994; 107:340-4. [PMID: 7968710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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46
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Jenkins R, Tyler S. Water births given a bad press. BMJ (CLINICAL RESEARCH ED.) 1994; 308:920. [PMID: 8173391 PMCID: PMC2539829 DOI: 10.1136/bmj.308.6933.920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Tyler S, Jenkins R. Can GPs reach the high Cs? THE HEALTH SERVICE JOURNAL 1994; 104:30. [PMID: 10132259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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48
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Tyler S. The RCM--an international success. MIDWIVES CHRONICLE 1993; 106:166. [PMID: 8510588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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49
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Tyler S. Twinning: supporting midwifery around the world. MIDWIVES CHRONICLE 1991; 104:357-8. [PMID: 1779899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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50
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Sathaye J, Tyler S. Transitions in Household Energy Use in Urban China, India, the Philippines, Thailand, and Hong Kong. ACTA ACUST UNITED AC 1991. [DOI: 10.1146/annurev.eg.16.110191.001455] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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