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Davies BR, Gilchrist FJ, Saunders A, Carroll WD. Annual hospitalization rates for children with asthma are inversely associated with total hours of sunshine in English regions. Clin Exp Allergy 2019; 47:838-840. [PMID: 28452084 DOI: 10.1111/cea.12946] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- B R Davies
- University Hospitals of the North Midlands, Stoke-on-Trent, UK
| | - F J Gilchrist
- University Hospitals of the North Midlands, Stoke-on-Trent, UK.,Keele University, Keele, UK
| | - A Saunders
- Derbyshire Children's Hospital, Derby, UK
| | - W D Carroll
- University Hospitals of the North Midlands, Stoke-on-Trent, UK.,Keele University, Keele, UK
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Turner NC, Alarcón E, Armstrong AC, Philco M, López Chuken YA, Sablin MP, Tamura K, Gómez Villanueva A, Pérez-Fidalgo JA, Cheung SYA, Corcoran C, Cullberg M, Davies BR, de Bruin EC, Foxley A, Lindemann JPO, Maudsley R, Moschetta M, Outhwaite E, Pass M, Rugman P, Schiavon G, Oliveira M. BEECH: a dose-finding run-in followed by a randomised phase II study assessing the efficacy of AKT inhibitor capivasertib (AZD5363) combined with paclitaxel in patients with estrogen receptor-positive advanced or metastatic breast cancer, and in a PIK3CA mutant sub-population. Ann Oncol 2019; 30:774-780. [PMID: 30860570 PMCID: PMC6551452 DOI: 10.1093/annonc/mdz086] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND BEECH investigated the efficacy of capivasertib (AZD5363), an oral inhibitor of AKT isoforms 1-3, in combination with the first-line weekly paclitaxel for advanced or metastatic estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) breast cancer, and in a phosphoinositide 3-kinase, catalytic, alpha polypeptide mutation sub-population (PIK3CA+). PATIENTS AND METHODS BEECH consisted of an open-label, phase Ib safety run-in (part A) in 38 patients with advanced breast cancer, and a randomised, placebo-controlled, double-blind, phase II expansion (part B) in 110 women with ER+/HER2- metastatic breast cancer. In part A, patients received paclitaxel 90 mg/m2 (days 1, 8 and 15 of a 28-day cycle) with capivasertib taken twice daily (b.i.d.) at two intermittent ascending dosing schedules. In part B, patients were randomly assigned, stratified by PIK3CA mutation status, to receive paclitaxel with either capivasertib or placebo. The primary end point for part A was safety to recommend a dose and schedule for part B; primary end points for part B were progression-free survival (PFS) in the overall and PIK3CA+ sub-population. RESULTS Capivasertib was well tolerated, with a 400 mg b.i.d. 4 days on/3 days off treatment schedule selected in part A. In part B, median PFS in the overall population was 10.9 months with capivasertib versus 8.4 months with placebo [hazard ratio (HR) 0.80; P = 0.308]. In the PIK3CA+ sub-population, median PFS was 10.9 months with capivasertib versus 10.8 months with placebo (HR 1.11; P = 0.760). Based on the Common Terminology Criteria for Adverse Event v4.0, the most common grade ≥3 adverse events in the capivasertib group were diarrhoea, hyperglycaemia, neutropoenia and maculopapular rash. Dose intensity of paclitaxel was similar in both groups. CONCLUSIONS Capivasertib had no apparent impact on the tolerability and dose intensity of paclitaxel. Adding capivasertib to weekly paclitaxel did not prolong PFS in the overall population or PIK3CA+ sub-population of ER+/HER2- advanced/metastatic breast cancer patients.ClinicalTrials.gov: NCT01625286.
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Affiliation(s)
- N C Turner
- Breast Unit, The Royal Marsden NHS Foundation Trust, London, UK; Breast Cancer Now Research Centre, The Institute of Cancer Research, London, UK.
| | - E Alarcón
- Clinical Oncology Department, British American Hospital, Lima, Peru
| | - A C Armstrong
- Department of Medical Oncology, Christie Hospital NHS Foundation Trust and Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - M Philco
- Peruvian Institute of Oncology Radiotherapy, Lima, Peru
| | | | - M-P Sablin
- Department of Drug Development and Innovation (D3i), Curie Institute, Paris, France
| | - K Tamura
- Department of Breast and Medical Oncology, National Cancer Center Hospital, Tokyo, Japan
| | | | - J A Pérez-Fidalgo
- Medical Oncology Unit, INCLIVA Biomedical Research Institute, University Clinical Hospital of Valencia, Valencia; CIBERONC, Health Institute Carlos III, Madrid, Spain
| | | | - C Corcoran
- Precision Medicine and Genomics, IMED Biotech Unit, AstraZeneca, Cambridge
| | - M Cullberg
- IMED Biotech Unit, AstraZeneca, Cambridge
| | - B R Davies
- IMED Biotech Unit, AstraZeneca, Cambridge
| | | | - A Foxley
- IMED Biotech Unit, AstraZeneca, Cambridge
| | | | - R Maudsley
- IMED Biotech Unit, AstraZeneca, Cambridge
| | | | | | - M Pass
- IMED Biotech Unit, AstraZeneca, Cambridge
| | - P Rugman
- IMED Biotech Unit, AstraZeneca, Cambridge
| | - G Schiavon
- IMED Biotech Unit, AstraZeneca, Cambridge
| | - M Oliveira
- Medical Oncology Department, Vall d'Hebron University Hospital and Vall d'Hebron Institute of Oncology (VHIO), Barcelona, Spain
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Davies BR, Leung AN, Dunne SM, Dillon J, Blum IR. Bespoke video vignettes - an approach to enhancing reflective learning developed by dental undergraduates and their clinical teachers. Eur J Dent Educ 2017; 21:33-36. [PMID: 26574189 DOI: 10.1111/eje.12175] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/06/2015] [Indexed: 06/05/2023]
Abstract
This study explores the selective use of video as a medium to support reflective processes as related to dental undergraduate learning. With the objective of developing and enhancing high-quality adult dental care, the use of compiled video materials created in an undergraduate clinical setting was investigated. Video cameras were used to capture elements of reflection-in-action and reflection-on-action typically found during everyday clinical practice. 'Gold standard' or 'textbook outcomes' are rarely, if ever, fully achieved in dental practice. Real-life clinical experiences offer challenges and opportunities for both teachers and students to engage with reflective learning processes. The materials generated allowed for an experience of individual reflective learning and the creation of a data bank or archive with potential use for the benefit of a wider student cohort. Various aspects of the students' views and comments on the process of reflection were reported and explored by means of a semi-structured focus group moderated by a linked educational advisor.
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Affiliation(s)
- B R Davies
- Primary Dental Care, King's College London Dental Institute, London, UK
| | - A N Leung
- Continuing Professional Development, Eastman Dental Institution, London, UK
| | - S M Dunne
- Primary Dental Care and Advanced General Dental Practice, King's College London Dental Institute, London, UK
| | - J Dillon
- Graduate School of Education, University of Bristol, Bristol, UK
| | - I R Blum
- Primary Dental Care, King's College London Dental Institute, London, UK
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Davies BR, Leung AN, Dunne SM. Why do general dental practitioners become involved in clinical teaching? A pilot study exploring the views of part-time practitioner teachers, King's College London. Br Dent J 2013; 214:461-5. [DOI: 10.1038/sj.bdj.2013.433] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/26/2013] [Indexed: 11/09/2022]
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Davies BR. An act of faith. Br Dent J 2013; 214:95. [DOI: 10.1038/sj.bdj.2013.116] [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: 11/09/2022]
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Abstract
Inhaled corticosteroids are established as the most effective long-term anti-inflammatory therapy for asthma. National and international treatment guidelines recommend the use of these agents for long-term asthma control in children. In children <5 years, there are significant difficulties in diagnosing asthma. There are multiple non-asthma causes of wheeze, and there remains a lack of consensus in the description of wheezing phenotypes in this group of children. There is also a relative paucity of data concerning the short- and long-term effectiveness and side-effects in the under-fives: treatment recommendations have drawn heavily from experience of asthma treatment in school-age children and remains controversial. This article discusses the important recent advances in the evidence-base and current expert opinions which are helping to delineate improved outcomes for young children with wheeze.
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Affiliation(s)
- B R Davies
- Nottingham University, Hospitals NHS Trust, Nottingham, UK
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Davies BR. STUDIES ON THE ZOOBENTHOS OF SOME SOUTHERN CAPE COASTAL LAKES. SPATIAL AND TEMPORAL CHANGES IN THE BENTHOS OF SWARTVLEI, SOUTH AFRICA, IN RELATION TO CHANGES IN THE SUBMERGED LITTORAL MACROPHYTE COMMUNITY. ACTA ACUST UNITED AC 2010. [DOI: 10.1080/03779688.1982.9633232] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Davies BR, Leung AN, Dunne SM. Perceptions of a simulated general dental practice facility - reported experiences from past students at the Maurice Wohl General Dental Practice Centre 2001–2008. Br Dent J 2009; 207:371-6. [DOI: 10.1038/sj.bdj.2009.902] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/24/2009] [Indexed: 11/09/2022]
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Rausch MD, Bernal I, Davies BR, Siegel A, Higbie FA, Westover GF. THE REACTION BETWEEN π-CYCLOPENTADIENYLDI-CARBONYLCOBALT AND PHENYLETHYNYLSILANE, AND AN X-RAY CRYSTALLOGRAPHIC INVESTIGATION OF ONE OF THE PRODUCTS, (π-CYCLOPENTADIENYL)-[trans-DIPHENYL-DI(TRIMETHYLSILYL)-CYCLOBUTADIENE]-COBALT. J COORD CHEM 2006. [DOI: 10.1080/00958977308073802] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Edmondson RJ, Monaghan JM, Davies BR. Gonadotropins mediate DNA synthesis and protection from spontaneous cell death in human ovarian surface epithelium. Int J Gynecol Cancer 2006; 16:171-7. [PMID: 16445629 DOI: 10.1111/j.1525-1438.2006.00274.x] [Citation(s) in RCA: 9] [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: 11/29/2022] Open
Abstract
Gonadotropins have been implicated in the development of epithelial ovarian cancers. These tumors are derived from ovarian surface epithelium (OSE). The purpose of this study was to determine the effects of these hormones on DNA synthesis and spontaneous cell death in primary cultures of OSE and three immortalized OSE cultures. Primary cultures of OSE cells were generated from the ovaries of women with benign disease. The effects of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) on DNA synthesis and cell death were determined using [(3)H]thymidine incorporation and JAM assays. Significant inductions of DNA synthesis were demonstrated with LH in 4/12 (33%) primary cultures of OSE and 2/3 OSE cell lines and with FSH in 4/11 (36%) primary cultures of OSE and 2/3 OSE cell lines. A significant protection from cell death was also observed in the presence of FSH in 2/4 primary cultures of OSE and 1/3 OSE cell lines and in the presence of LH in 1/4 primary cultures of OSE and 2/3 OSE cell lines. The results indicate that while gonadotropins have the potential to induce cell proliferation and protect from cell death in OSE cells in vitro, their effects are variable in OSE cells from different women.
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Affiliation(s)
- R J Edmondson
- Northern Gynaecological Oncology Centre, Queen Elizabeth Hospital, Gateshead, Tyne and Wear NE9 6SX, UK.
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Dovedi SJ, Kirby JA, Atkins H, Davies BR, Kelly JD. Cyclooxygenase-2 inhibition: a potential mechanism for increasing the efficacy of bacillus calmette-guerin immunotherapy for bladder cancer. J Urol 2005; 174:332-7; discussion 337. [PMID: 15947685 DOI: 10.1097/01.ju.0000161589.85869.ae] [Citation(s) in RCA: 19] [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: 11/25/2022]
Abstract
PURPOSE Intravesical bacillus Calmette-Guerin (BCG) therapy is the principal treatment for high risk, noninvasive urothelial carcinoma and carcinoma in situ of the bladder. However, up to 40% of patients fail to respond to this treatment. In this study the potential for inhibition of PGE2 production by BCG treated dendritic cells (DCs) was studied in the context of preferential polarization of the immune response toward a cancer clearing T-helper type 1 immune response. MATERIALS AND METHODS Murine bone marrow derived DCs were cultured with interleukin (IL)-4 and granulocyte-macrophage colony-stimulating factor. After 7 days the cells were stimulated with BCG. Cell surface expression of co-stimulatory molecules and phagocytic ability were measured by flow cytometry analysis to verify cell activation. The production of IL-10 and IL-12 was measured after DC stimulation with BCG in the presence of IL-10, prostaglandin E2(Cayman Chemical, Ann Arbor, Michigan), antiIL-10 antibody (Insight Biotechnology, Wembley, United Kingdom), NS-398 and indomethacin (Sigma, Poole, United Kingdom). RESULTS Prostaglandin E2 stimulated a dose dependent increase in the levels of IL-10 produced by BCG activated DCs (p <0.01). IL-10 significantly decreased IL-12 production (p <0.001), while IL-10 blockade significantly increased IL-12 levels (p <0.05). The COX-2 selective inhibitor NS-398 caused a dose dependent increase in the concentration of IL-12 produced by BCG activated DCs (p <0.01). This effect was also seen with the partially selective COX-1 inhibitor indomethacin (p <0.05). CONCLUSIONS The inhibition of PGE2 synthesis by COX inhibition favored the production of IL-12 by BCG activated DC. This potentially will result in the generation of a T-helper type 1, polarized T-cell response that may improve the efficacy of BCG therapy.
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Affiliation(s)
- S J Dovedi
- Department of Surgery/Northern Institute for Cancer Research, Medical School, University of Newcastle, Newcastle-Upon-Tyne, United Kingdom.
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Mehrotra P, Okpokam A, Bouhaidar R, Johnson SJ, Wilson JA, Davies BR, Lennard TWJ. Galectin-3 does not reliably distinguish benign from malignant thyroid neoplasms. Histopathology 2005; 45:493-500. [PMID: 15500653 DOI: 10.1111/j.1365-2559.2004.01978.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [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: 11/26/2022]
Abstract
AIMS To determine whether galectin-3 is a sensitive indicator of thyroid malignancy. It has been suggested as a potential marker for differentiating thyroid carcinoma from benign or non-neoplastic lesions in preoperative fine-needle aspirates (FNAs). METHODS Galectin-3 protein expression was assessed by immunohistochemistry in formalin-fixed thyroid tissues from 124 patients with histological diagnoses of papillary carcinoma (n = 38), follicular carcinoma (n = 19), follicular adenoma (n = 32) and dominant nodules of multinodular goitre (n = 35). Expression of galectin-3 was also assessed by Western blotting in 24 fresh thyroid tissues. RESULTS Galectin-3 expression was observed in the majority of carcinomas (papillary 92%; follicular 74%). However, a large proportion of follicular adenomas (72%) and multinodular goitres (57%) also expressed galectin-3. In addition, galectin-3 expression was observed in epithelial cells of normal thyroid tissue and Hashimoto's thyroiditis. Galectin-3 immunopositivity was significantly greater in papillary carcinomas than in dominant nodules or follicular adenomas (P < 0.0001, P = 0.0005, respectively). However, galectin-3 expression was no greater in follicular carcinomas than in follicular adenomas (P = 0.8735). Western blotting analysis confirmed both the specificity of the antiserum and expression of galectin-3 in multinodular goitres, follicular adenomas/carcinomas and papillary carcinomas. CONCLUSION The data demonstrate that galectin-3 is not a reliable immunohistochemical marker to distinguish benign from malignant thyroid follicular lesions.
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Affiliation(s)
- P Mehrotra
- School of Surgical and Reproductive Sciences, University of Newcastle upon Tyne, Newcastle upon Tyne, UK
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Abstract
Nurses should address the concerns of service users in research and engage in collaborative work with them. Doing this presents ethical dilemmas, not least around the issues of assessing capacity and informed consent to participation in research. The view that judgement regarding the capacity to consent is solely the responsibility of a consultant psychiatrist is challenged as inadequate. The concept of 'moral discourse' (Pike 1991) is used to understand the process by which the assessment of capacity may be carried out. This is illustrated by the application of the concept in a qualitative research study carried out to explore what makes mental health services accessible to women with children. The role of the mental health nurse entails surveillance and the development of expertise in negotiating compliance with treatment programmes. The paper outlines the measures taken to ensure that service users felt empowered, rather than coerced, to participate in this study. While Community Mental Health Team workers were engaged in 'moral discourse' in respect of participation by service users in the study, there were difficulties in engaging General Practitioners. However, there was evidence that women themselves felt empowered both to express interest in participating and to withdraw if they so wished.
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Affiliation(s)
- B R Davies
- East Vale Community Mental Health Team, Cardiff and Vale NHS Trust, UK.
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Robinson PB, Davies BR. Reflective practice in the teaching of conservative dentistry to undergraduate dental students - perceptions derived from a pilot study using personal development diaries. Eur J Dent Educ 2004; 8:67-71. [PMID: 15059082 DOI: 10.1111/j.1600-0579.2004.00314.x] [Citation(s) in RCA: 5] [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: 05/24/2023]
Abstract
The aim of this study was to explore final-year student perceptions to the use of personal development diaries (PDDs) and to compare the findings with an established system of competitive continuous assessment, using open display of score ratings displayed on a clinic notice board. Focus groups in conjunction with personal development diaries (PDDs) were used to investigate the teaching of conservative dentistry to senior dental undergraduates. Thirty per cent of the statements made reference to the positive aspects of PDDs, while a small percentage (6%) was negative. Nineteen per cent of the comments derived from the focus groups showed that the undergraduates disliked the open display of their marks on the conservation clinic notice board. This compared with only 2% who claimed that they enjoyed the competitive method. A further 22% of the comments related to the fact that open display of marks was stressful, whereas 3% were unaffected. Eighteen per cent of the responses indicated that clinical conservative dentistry was a stressful experience.
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Affiliation(s)
- P B Robinson
- Guy's King's and St Thomas' Hospital Schools of Medicine and Dentistry and Biomedical Sciences, The King's Denmark Hill Campus, The Dental Institute, Caldecote Road, London SE5 9RW, UK.
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Atkins H, Davies BR, Kirby JA, Kelly JD. Polarisation of a T-helper cell immune response by activation of dendritic cells with CpG-containing oligonucleotides: a potential therapeutic regime for bladder cancer immunotherapy. Br J Cancer 2004; 89:2312-9. [PMID: 14676812 PMCID: PMC2395264 DOI: 10.1038/sj.bjc.6601474] [Citation(s) in RCA: 22] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Intravesical bacillus Calmette–Guerin (BCG) is a treatment for transitional cell carcinoma (TCC) and carcinoma in situ (cis) of the urinary bladder, but some patients remain refractory. The mechanism of cancer clearance is not known, but T cells are thought to play a contributory role. Tissue dendritic cells (DCs) are known to initiate antigen-specific immune responses following activation of receptors, which recognise molecular patterns on the surface of microorganisms. A family of these receptors, the toll-like receptors (TLRs), are also crucial for activating DC to produce cytokines that polarise the T-cell response towards a T helper (Th)1 or Th2 phenotype. This study compared the potential of intact BCG to activate DC with that of the defined TLR4 ligand lipopolysaccharide (LPS) and the TLR9 ligand CpG-oligonucleotide. It was found that all three stimuli efficiently activated normal DC, but cells expressing a mutant TLR4 responded poorly to stimulation with LPS. Importantly, stimulation with BCG induced both IL-12 and IL-10, suggesting subsequent development of a poorly focused T-cell immune response containing both Th1 and Th2 immune function. By contrast, LPS- and CpG-oligonucleotides induced only IL-12, indicating the potential to produce a Th1 response, which is likely to clear cancer most efficiently. Given the toxicity of LPS, our data suggest that CpG-oligonucleotides may be beneficial for intravesical therapy of bladder cancer.
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Affiliation(s)
- H Atkins
- Northern Institute for Cancer Research, School of Surgical and Reproductive Sciences, Faculty of Medical Sciences, University of Newcastle, Framlington Place, Newcastle-Upon-Tyne NE2 4HH, UK
| | - B R Davies
- Northern Institute for Cancer Research, School of Surgical and Reproductive Sciences, Faculty of Medical Sciences, University of Newcastle, Framlington Place, Newcastle-Upon-Tyne NE2 4HH, UK
| | - J A Kirby
- Northern Institute for Cancer Research, School of Surgical and Reproductive Sciences, Faculty of Medical Sciences, University of Newcastle, Framlington Place, Newcastle-Upon-Tyne NE2 4HH, UK
- Northern Institute for Cancer Research, School of Surgical and Reproductive Sciences, Faculty of Medical Sciences, University of Newcastle, Framlington Place, Newcastle-Upon-Tyne NE2 4HH, UK. E-mail:
| | - J D Kelly
- Northern Institute for Cancer Research, School of Surgical and Reproductive Sciences, Faculty of Medical Sciences, University of Newcastle, Framlington Place, Newcastle-Upon-Tyne NE2 4HH, UK
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Strathdee G, Davies BR, Vass JK, Siddiqui N, Brown R. Cell type-specific methylation of an intronic CpG island controls expression of the MCJ gene. Carcinogenesis 2004; 25:693-701. [PMID: 14729589 DOI: 10.1093/carcin/bgh066] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [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: 11/13/2022] Open
Abstract
Over 50% of human genes are associated with CpG islands and DNA methylation within such CpG islands has been clearly correlated with inhibition of expression. Whereas changes in DNA methylation play a key role in a number of human diseases, in particular cancer, in normal DNA CpG islands are nearly always methylation free, regardless of the expression status of the associated gene. Only limited evidence supports a role for DNA methylation in controlling tissue-specific expression in adult somatic tissue. Loss of expression of the MCJ gene has previously been linked to increased chemotherapeutic drug resistance in ovarian cancer. We report that loss of expression of MCJ in drug-resistant ovarian cancer cell lines depends on methylation of a CpG island within its first exon, but is independent of methylation within the promoter region. Furthermore, cell type-specific expression of the MCJ gene in normal cells also depends on the methylation status of the CpG island within its first exon. The MCJ CpG island is methylated and the gene is not expressed in cells of epithelial origin, but unmethylated and expressed in cells of lymphocyte or fibroblast origin. Chromatin immunoprecipitation assays determined that MCJ CpG island methylation was associated with loss of histone acetylation in ovarian epithelial cells compared with unmethylated fibroblast cells. Reduced acetylation was observed not only within the CpG island, but also within the promoter region, suggesting that CpG island methylation may direct alterations in chromatin structure within the promoter region, leading to gene inactivation.
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Affiliation(s)
- G Strathdee
- Department of Medical Oncology, Cancer Research UK Beatson Laboratories, Glasgow University, Glasgow G61 1BD, Scotland, UK.
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Cassells-Brown A, Morrell AJ, Davies BR, Topping NC. Wegener's granulomatosis causing lid destruction: a further sight-threatening complication. Eye (Lond) 2003; 17:652-4. [PMID: 12855978 DOI: 10.1038/sj.eye.6700410] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Abstract
Metastasis is usually responsible for mortality in patients suffering from muscle invasive bladder cancer. Whilst expression of a great number of genes and their protein products have been associated with metastasis and/or poor prognosis in bladder cancer, evidence that they actively drive the metastatic process, and hence make potentially good therapeutic targets, is often lacking. This is due to the limited number and application of effective animal models which reflect the pathogenesis of the human disease. In this review I will discuss the processes involved in metastasis, consider the established animal models of bladder cancer progression and metastasis, and review the evidence for a role of various gene products in this process. Consideration of clinical studies in conjunction with evidence from experimental animal models reveals that the tyrosine kinase receptor erbB1/EGFR, the calcium binding protein S100A4 and the the cell cycle arrest/apoptosis-inducing p53 protein are amongst the most promising targets for therapy against metastatic disease in patients with bladder cancer.
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Affiliation(s)
- B R Davies
- Northern Institute for Cancer Research, and School of Surgical and Reproductive Sciences, The Medical School, University of Newcastle, Newcastle-Upon-Tyne, UK.
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Edmondson RJ, Monaghan JM, Davies BR. The human ovarian surface epithelium is an androgen responsive tissue. Br J Cancer 2002; 86:879-85. [PMID: 11953818 PMCID: PMC2364138 DOI: 10.1038/sj.bjc.6600154] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2001] [Revised: 12/13/2001] [Accepted: 12/17/2001] [Indexed: 12/02/2022] Open
Abstract
The pathogenesis of epithelial ovarian cancer remains unclear. From epidemiological studies raised levels of androgens have been implicated to increase the risk of developing the disease. The purpose of this study was to determine the responses of normal human ovarian surface epithelium to androgens. We have established primary cultures of human ovarian surface epithelium from patients undergoing oophorectomy for benign disease. Total RNA was isolated from these cultures and expression of mRNA encoding for the androgen receptor was demonstrated using reverse transcriptase polymerase chain reaction. The presence of androgen receptor in sections of normal ovary was also investigated using an antibody against androgen receptor. The effects of androgens on DNA synthesis and cell death were determined. Eight out of eight (100%) cultures expressed mRNA encoding the androgen receptor. The presence of androgen receptor in ovarian surface epithelium of sections of normal ovaries was demonstrated in all sections. Mibolerone, a synthetic androgen, caused a significant stimulation of DNA synthesis in 5 out of 9 (55%) cultures when used at a concentration of 1 nM. Mibolerone also caused a significant decrease in cell death in 2 out of 5 (40%) cultures tested. We have demonstrated that the ovarian surface epithelium is an androgen responsive tissue and that androgens can cause an increase in proliferation and a decrease in cell death. These findings have important implications for the pathophysiology of ovarian carcinogenesis.
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Affiliation(s)
- R J Edmondson
- Department of Surgery, University of Newcastle upon Tyne, Medical School, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
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Steele IA, Edmondson RJ, Bulmer JN, Bolger BS, Leung HY, Davies BR. Induction of FGF receptor 2-IIIb expression and response to its ligands in epithelial ovarian cancer. Oncogene 2001; 20:5878-87. [PMID: 11593393 DOI: 10.1038/sj.onc.1204755] [Citation(s) in RCA: 46] [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] [Received: 01/24/2001] [Revised: 04/12/2001] [Accepted: 06/26/2001] [Indexed: 11/08/2022]
Abstract
Epithelial ovarian cancers (EOCs) arise in the Ovarian Surface Epithelium (OSE). This tissue is a simple, poorly committed mesothelium which exhibits characteristics of epithelial and mesenchymal cells when grown in culture. In contrast, EOCs frequently exhibit properties of complex epithelial tissues of the female reproductive tract, such as oviductal, endometrial and cervical epithelia, and show induction of expression of epithelial markers such as E-cadherin. Fibroblast Growth Factor Receptor 2 isoform IIIb (FGF receptor 2-IIIb) is a spliced variant of FGF receptor 2 that binds the ligands FGF-1 and FGF-7 with high affinity, and is expressed exclusively by epithelial cells. We have studied the expression of FGF receptor 2-IIIb and its ligands in primary cultures of normal human OSE, EOC cell lines and snap frozen tissue from EOCs. Expression of FGF receptor 2-IIIb mRNA is undetectable in normal OSE, but is expressed in 16/20 (80%) of EOCs. FGFs 1 and 7 mRNAs are expressed in normal OSE, whilst only 4/20 (20%) and 12/20 (60%) of EOCs demonstrated expression for these ligands respectively. However, FGF-7 protein was detected in 70% (mean level=0.7 ng/ml) of ascitic fluids obtained from patients with EOC. FGFs 1 and 7 stimulate DNA synthesis in EOC cell lines that express FGF receptor 2-IIIb. Moreover, DNA synthesis in these cell lines can be partially blocked by blocking antisera to FGFs 1 and 7. It is suggested that induction of expression of FGF receptor 2-IIIb may play a role in the development of EOCs by rendering the OSE susceptible to paracrine and/or autocrine stimulation by its requisite FGF ligands.
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Affiliation(s)
- I A Steele
- Department of Surgery, The Medical School, University of Newcastle-upon-Tyne, Newcastle-upon-Tyne, NE2 4HH, UK
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23
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Abstract
BACKGROUND The amniotic band disruption complex (ABDC) has been segregated recently into various phenotypes. In view of the pathogenic mechanisms that have been proposed, this study was designed to assess if it is one variable process or is composed of several distinct complexes. METHODS The 48 cases of fetuses with bands or placenta attached to fetal parts cited in this paper included nine new cases and 39 from the literature. They were organized first according to the embryonal topography of the malformations, then according to the position of the adhesions, and finally by the assessment of distances between the cases and between the malformations using the squared Euclidean distances for binary variables and cluster analysis. RESULTS In all three analyses, three groups were identified: 1) fetuses with cephalo-thoracic anomalies; 2) fetuses with caudal anomalies, and 3) fetuses with mixed anomalies. Nonetheless, overlap among the three groups was apparent. Thus, while fetuses with amniotic bands form three clusters, it appears that these are part of a spectrum and should be considered as variable manifestations of a single entity resulting from a single pathogenetic mechanism. An association was established between the localization of the adhesions and the malformations in various axes. Abdominoschisis, however, was not particularly related to adhesions at one or the other end of the fetus; a short umbilical cord was an almost universal finding. Single umbilical artery (SUA) was especially related to caudal adhesions and malformations (p = 0.004 and 0.001), as well as abdominoschisis (p = 0.002) and agenesis of the abdominal organs (p = 0.008). CONCLUSIONS The association between amniotic adhesions to the fetus and multiple malformations occurring predominantly in the same area suggest that the former are the cause of the latter. The association of abdominoschisis, as well as a short umbilical cord, with malformations and adhesions in all areas, suggests that these are secondary phenomena to generalized embryonal and fetal tension. SUA, however, with a specifically regional association, is more likely to be due to disruption from exposure in cases with abdominoschisis, often accompanying the loss of abdominal organs.
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Affiliation(s)
- B R Davies
- Departamento de Patología, Hospital General de México y Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico
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24
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Abstract
BACKGROUND The objective of the study was to investigate the possibility of the effect of seasonal temperature on the incidence of lethal congenital malformations in a retrospective study. METHODS At the National Institute of Perinatology in Mexico City, perinatal deaths due to congenital malformations were compared with the the remainder of perinatal deaths over a period of 3 years in relation to the average temperature of the months in which the fifth week of gestation occurred. RESULTS The division between the average temperature of the individual months was 18 degrees C, as there were no months with an average between 17.9 and 18.8 degrees C. An average of 0.86 perinatal deaths with lethal malformations had spent their embryonic life in a cold month, whereas an average of 1.54 had spent their embryonic life in a hot month; in contrast, an average of 10.24 perinatal deaths with lethal malformations had spent their embryonic life in a cold month, and a smaller number (9.23) in a hot month. CONCLUSIONS The perinatal deaths with lethal malformations therefore showed a significant tendency to have spent their embryonic lives during the hotter months in comparison with the other perinatal fetal deaths (p = 0.04). Further studies should be made with larger numbers of cases, maintaining careful attention to early perinatal data and local temperatures.
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Affiliation(s)
- B R Davies
- Departamento de Patología, Instituto Nacional de Perinatología, Secretaría de Salud (SSa), Mexico City, Mexico
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Davies BR, Platt-Higgins AM, Schmidt G, Rudland PS. Development of hyperplasias, preneoplasias, and mammary tumors in MMTV-c-erbB-2 and MMTV-TGFalpha transgenic rats. Am J Pathol 1999; 155:303-14. [PMID: 10393862 PMCID: PMC1866674 DOI: 10.1016/s0002-9440(10)65124-3] [Citation(s) in RCA: 28] [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] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Human cDNAs corresponding to two epidermal growth factor-related products that are overexpressed in human breast cancers, that for c-erbB-2 (HER-2) and for transforming growth factor alpha (TGFalpha), have been cloned downstream of the mouse mammary tumor virus (MMTV) long terminal repeat promoter and injected into the pronucleus of fertilized oocytes of Sprague-Dawley rats to produce transgenic offspring. Expression of the transgenic mRNAs is not detectable in mammary tissue from virgin transgenic rats but is detected in mammary tissue from certain lines of mid-pregnant transgenic rats. When two such lines of either type of transgenic rat are subjected to repeated cycles of pregnancy and lactation, they produce, primarily in the mammary glands, extensive pathologies, whereas virgin transgenic rats produce no such abnormalities. Multiparous transgenic female offspring from c-erbB-2-expressing lines develop a variety of focal hyperplastic and benign lesions that resemble lesions commonly found in human breasts. These lesions include lobular and ductal hyperplasia, fibroadenoma, cystic expansions, and papillary adenomas. More malignant lesions, including ductal carcinoma in situ and carcinoma, also develop stochastically at low frequency. The mammary glands of transgenic females invariably fail to involute fully after lactation. Similar phenotypes are observed in female MMTV-TGFalpha transgenic rats. In addition, multiparous TGFalpha-expressing female transgenics frequently develop severe pregnancy-dependent lactating hyperplasias as well as residual lobules of hyperplastic secretory epithelium and genuine lactating adenomas after weaning. These transgenic rat models confirm the conclusions reached in transgenic mice that overexpression of the c-erbB-2 and TGFalpha genes predisposes the mammary gland to stochastic tumor development.
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Affiliation(s)
- B R Davies
- Department of Surgery,* School of Surgical Sciences, The Medical School, University of Newcastle-Upon-Tyne, Cambridge, United Kingdom.
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26
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Abstract
Little is known concerning the proliferation of the ovarian surface epithelium or the factors which control this process. To define when and under what circumstances this epithelium proliferates, we have studied the proliferation of mouse ovarian surface epithelium (OSE) during embryogenesis, early postnatal life, various physiological circumstances in the adult and in response to gonadotropic hormones, using the bromodeoxyuridine technique. Proliferation of the OSE is greatest during embryonic development, and falls gradually after birth until sexual maturity is reached. Very little proliferation of the OSE is detectable in adult life in non-pregnant, pregnant or lactating mice. The basal proliferation of the OSE can be increased significantly by inducing follicular development with pregnant mare serum gonadotropin (PMSG) or by administration of the pure recombinant gonadotropins follicle-stimulating hormone (FSH) or luteinizing hormone (LH). These results show that administration of gonadotropins to sexually mature mice induces proliferation of ovarian surface epithelium concurrently with the process of folliculogenesis.
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Affiliation(s)
- B R Davies
- Department of Surgery, School of Surgical Sciences, Medical School, University of Newcastle-Upon-Tyne, UK
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27
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Snaddon CD, Davies BR. A preliminary assessment of the effects of a small south african inter-basin water transfer on discharge and invertebrate community structure. ACTA ACUST UNITED AC 1998. [DOI: 10.1002/(sici)1099-1646(1998090)14:5<421::aid-rrr509>3.0.co;2-l] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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28
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Davies BR, Warren JR, Schmidt G, Rudland PS. Induction of a variety of preneoplasias and tumours in the mammary glands of transgenic rats. Biochem Soc Symp 1998; 63:167-84. [PMID: 9513721] [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] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Although transgenic mouse models for breast cancer have frequently been reported in the literature, transgenic rat models have not been described. We have generated transgenic rats overexpressing the human transforming growth factor alpha (TGF alpha) and c-erbB-2 genes in the mammary gland under the control of the mouse mammary tumour virus (MMTV) long terminal repeat promoter, and have analysed multiple lines of these rats to the second (F2) generation. Female MMTV/TGF alpha rats frequently develop severe hyperplasias during pregnancy, and a variety of tumours of long latency. The mammary glands of MMTV/TGF alpha rats fail to involute fully after the completion of lactation. Expression of the TGF alpha transgene is highest in the hyperplasias. MMTV/c-erbB-2 female rats develop a spectrum of benign and malignant lesions, including ductal carcinoma in situ and carcinomas. Expression of the c-erbB-2 transgene is found in benign tumours such as fibroadenomas, but is highest in the carcinomas. These animals model a spectrum of lesions found in human breasts and suggest that TGF alpha overexpression can act at a relatively early stage in the pathogenesis of breast cancer in the rat, resulting in a predominantly hyperplastic response, whereas overexpression of c-erbB-2 plays a role in the induction of various benign lesions and more advanced breast carcinomas.
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Affiliation(s)
- B R Davies
- Department of Pathology, Addenbrookes Hospital, University of Cambridge, U.K
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29
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Barraclough R, Chen HJ, Davies BR, Davies MP, Ke Y, Lloyd BH, Oates A, Rudland PS. Use of DNA transfer in the induction of metastasis in experimental mammary systems. Biochem Soc Symp 1998; 63:273-94. [PMID: 9513730] [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] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The metastatic spread of cancer is a little understood process, in part because it is difficult to model the entire process using experimental approaches in vitro. The ability to transfer DNA into non-metastatic mammary cells and to observe the induction of metastasis in vivo provides a means for identifying DNA sequences that are associated with the development of metastatic capability. Using these techniques, a metastasis-associated cytoskeletal calcium binding protein, S100A4 (p9Ka), has been identified as an inducer of metastatic capability in benign rat mammary epithelial cells. Metastasis can also be induced in the rat mammary epithelial cells by fragments of DNA from metastatic, but not from benign, human breast tumour cells. These non-coding fragments of DNA act via the induction of osteopontin, an extracellular, integrin binding, calcium binding protein. Since both osteopontin and S100A4 are thought to be associated with malignancy in human breast cancer specimens, gene transfer techniques can identify genes for metastasis-inducing proteins that may play a role in breast cancer, and further suggest that cell migration/motility might be important in the metastatic process.
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Affiliation(s)
- R Barraclough
- Department of Biochemistry, University of Liverpool, U.K
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30
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Davies BR, Auersperg N, Worsley SD, Ponder BA. Transfection of rat ovarian surface epithelium with erb-B2/neu induces transformed phenotypes in vitro and the tumorigenic phenotype in vivo. Am J Pathol 1998; 152:297-306. [PMID: 9422547 PMCID: PMC1858128] [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] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The neu/cerb-B2 gene is frequently amplified and/or overexpressed in human epithelial ovarian cancers. We have established an inbred animal model for ovarian cancer that mimics aspects of human ovarian cancer by transducing a spontaneously immortalized rat ovarian surface epithelial cell line in culture with ecotropic retroviruses expressing a mutated rat neu/c-erb-B2 oncogene. Transfectants expressing neu at a high level exhibited altered morphology and behavior in two-dimensional and three-dimensional culture in Matrigel, could be cloned in soft agar, and were more invasive through a Matrigel membrane than control transfectants transduced with a similar retrovirus expressing the beta-galactosidase gene. When injected intraperitoneally, neu-expressing transfectants produced highly invasive, rapidly growing tumors that coated the peritoneal cavity and induced ascites formation. Furthermore, neu transfectants could be grown as solid tumors when injected subepithelially into the ovary. The neu-transfected cells also formed tumors when injected subcutaneously into the mammary fat pad, although they grew relatively poorly and often regressed. Transfectants expressing beta-galactosidase failed to produce tumors at any of the sites injected. A second rat ovarian surface epithelial cell line was similarly transduced with the neu/c-erb-B2-expressing retrovirus. However, transformed phenotypes and tumorigenicity were not induced in this cell line. These experiments show directly that overexpression of neu in an established line of rat ovarian epithelium is extremely oncogenic. This animal model system may prove useful for the study of ovarian cancer biology in immunocompetent animals.
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Affiliation(s)
- B R Davies
- WellBeing Ovarian Cancer Research Centre, University of Cambridge, Addenbrookes Hospital, United Kingdom.
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31
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Davies BR, Worsley SD, Ponder BA. Expression of E-cadherin, alpha-catenin and beta-catenin in normal ovarian surface epithelium and epithelial ovarian cancers. Histopathology 1998; 32:69-80. [PMID: 9522220 DOI: 10.1046/j.1365-2559.1998.00341.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.7] [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: 02/06/2023]
Abstract
AIMS To study the expression of the epithelial adhesion molecule E-cadherin and its associated proteins alpha and beta catenin in paraffin sections of normal ovaries, benign cystadenomas and ovarian carcinomas, and in immortalized normal ovarian surface epithelial cells and ovarian carcinoma cells in culture. METHODS AND RESULTS Immunocytochemistry was used to study expression of the proteins in paraffin sections and western blotting was used to determine levels of expression of the proteins in cell extracts. E-cadherin expression was found to be absent in ovarian surface epithelial cells in culture and infrequently expressed in normal ovarian surface epithelial cells in vivo, although apical punctate staining was occasionally seen. Seven of nine benign cystadenomas and 29/34 epithelial ovarian carcinomas showed some expression of E-cadherin, but expression was absent in poorly differentiated tumours. Expression of alpha and beta catenin was consistently detected on the lateral membranes of normal ovarian epithelium and benign cystadenomas. alpha and beta catenin expression was lost in 18% and 21% of ovarian carcinomas, respectively: other ovarian carcinomas expressed these proteins at a reduced level. A small number of these tumours showed a diffuse cytoplasmic rather than membranous staining. Reduced staining for alpha and beta catenin appeared to correlate with a more spindly, less adhesive morphology and increased invasive potential in matrigel. CONCLUSIONS The results suggest that E-cadherin expression is generally induced in well differentiated ovarian cancers. In contrast, alpha and beta catenins are consistently expressed in the normal ovarian surface epithelium and benign tumours, but are sometimes reduced or absent in ovarian carcinomas. It is likely that the catenins associate with membrane proteins other than E-cadherin in ovarian epithelium, and they may possibly function as tumour suppressors in this epithelium.
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Affiliation(s)
- B R Davies
- WellBeing Ovarian Cancer Research Centre, University of Cambridge, Addenbrookes Hospital, UK
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32
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Leung EH, Davies BR, Leung PC, Chen GT, Roskelley CD, Auersperg N. Efficient introduction of genes into human ovarian surface epithelium. In Vitro Cell Dev Biol Anim 1997; 33:665-7. [PMID: 9358278 DOI: 10.1007/s11626-997-0120-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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33
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Davies BR, Millar BJ, Wood DJ, Bubb NL. Strength of secondary-cured resin composite inlay repairs. Quintessence Int 1997; 28:415-8. [PMID: 9477907] [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] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A study was designed to simulate the repair of an indirect resin composite restoration with conventionally cured resin composite. Two-part specimens were prepared to test the diametral tensile strength of the repair interface between the base material of an indirectly cured resin composite (Herculite XRV) and repairs carried out with three directly cured materials (Herculite XRV, TPH, and Charisma). The repairs were carried out with and without use of the bonding resin for the repair material. The diametral tensile strengths of all repaired specimens were significantly less than those of bulk unrepaired specimens. There were no significant differences between the diametral tensile strengths of repaired blocks when the repair materials were used without bonding resin. The use of an intermediate layer of bonding resin significantly increased the bond strengths obtained when Herculite XRV and TPH were used for repair. There was no significant difference between the strength values of Herculite XRV and TPH, but Charisma exhibited the lowest strengths of repaired specimens.
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Affiliation(s)
- B R Davies
- Department of Conservative Dentistry, King's Dental Institute, London, United Kingdom
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34
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Abstract
Amplification and overexpression of the cell cycle-related gene cyclin D1 have been demonstrated in several human malignancies and have been shown to be directly oncogenic in breast epithelium and lymphocytes. Overexpression of the gene can occur in the absence of gene amplification. We have investigated whether cyclin D1 is overexpressed in a panel of 43 sporadic epithelial ovarian cancers using immunohistochemistry. Cyclin D1 was overexpressed in 26% of these tumors. Overexpression of cyclin D1 is associated with borderline or well-differentiated, grade 1 tumors but does not correlate with a particular histological type, overexpression of the c-erb-B2 oncogene, or presence of estrogen receptors. It is suggested that overexpression of cyclin D1 may contribute to the pathogenesis of epithelial ovarian cancers, including a subset of tumors different from those overexpressing the c-erb-B2 oncogene.
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Affiliation(s)
- S D Worsley
- Wellbeing Ovarian Cancer Research Centre, Department of Pathology, University of Cambridge, United Kingdom
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35
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Abstract
The aims of this study were to: 1. survey the light output from 49 light-curing units in clinical use; 2. measure the effect on depth of cure of composite resin caused by a range of light outputs; 3. assess the relationship between radiometer meter readings and depth of cure of composite resin in a human tooth model and a Heliotest. The mean meter reading produced by the 49 lights surveyed using a lampChecker radiometer was 4.4 (+/-2.4 SD), range 0.3 to 10.0. The manufacturer of the radiometer considers optimal light output to provide a meter reading within the range 5.0 to 7.0. Lights of very low output (0.7 +/- 0.1 SD) were found to be capable of curing, after 20 seconds, a 1.9 (+/-0.3 SD) mm thickness of composite resin. However, only approximately 50% of this thickness can be considered fully cured. Increasing the cure time from 20 seconds to 60 seconds increased the mean depths of cure by a factor of approximately 1.4. The mean depths of cure of composite resin placed in the Heliotest were greater than those observed in the natural tooth model, by a factor of approximately 1.3. Correlation coefficients of meter readings and depth of cure were greater for the Efos Cure Rite and Demetron 100 radiometers than the lampChecker unit.
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Affiliation(s)
- S M Dunne
- Department of Conservative Dentistry, King's College School of Medicine and Dentistry, London
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36
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Davies BR, Fernig DG, Barraclough R, Rudland PS. Effect on tumorigenicity and metastasis of transfection of a diploid benign rat mammary epithelial cell line with DNA corresponding to the mRNA for basic fibroblast growth factor. Int J Cancer 1996; 65:104-11. [PMID: 8543386 DOI: 10.1002/(sici)1097-0215(19960103)65:1<104::aid-ijc18>3.0.co;2-g] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
To examine the potential role of fibroblast growth factors (FGF) in tumorigenesis and metastasis, plasmid constructs containing the human basic FGF (bFGF) gene, with or without fusion to a secretory signal peptide (IgbFGF), were transfected into the diploid rat mammary epithelial cell line Rama 37. All transfectants possessed multiple copies of the transfected cDNA, which was expressed as the corresponding mRNA and the protein. The amount of bFGF protein was usually greater than the bFGF growth-stimulatory activity that could be recovered from the transfected cells. Nevertheless, the amount of bFGF growth-stimulatory activity secreted by the IgbFGF transfectants (0.08-0.8 ng/ml/24 hr) was sufficient to induce growth in responsive cells. However, the transfectants themselves were refractory to stimulation by exogenously added bFGF, despite possessing a small number of high-affinity receptors for bFGF. When the bFGF or the IgbFGF transfectants were inoculated into the mammary fat pads of syngeneic rats, the tumour incidence was low (0-50%). However, when cells cultured from these tumours were inoculated into the fat pad of syngeneic rats, the tumour incidence was 100%. Tumours were in all cases benign and no metastases were observed. Our results suggest that the role of bFGF in metastasis is not simply one of autocrine/paracrine stimulation of cell growth and that other events may also be required.
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Affiliation(s)
- B R Davies
- Department of Biochemistry, University of Liverpool, UK
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37
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Abstract
To assist seating or relocation of resin-bonded retainers on abutments, extensions of the cast framework can be incorporated and removed after cementation. There has been apprehension concerning the heat created during the grinding of these extensions, particularly if there is a substantial bulk of metal. This study recorded the elevation of temperature when cast incisal extensions were removed by grinding after cementation. A total of 20 retainers were waxed for 0.3 mm thickness, cast in a nickel-chrome alloy, and bonded in-vitro to an acid-etched natural tooth with composite resin cement. The temperature of the coronal dentin was measured while the tag was ground with a high-speed dental handpiece. The maximum temperature and mean temperature elevations that exceeded the resting temperature were recorded. A significant temperature rise was apparent when complete incisal wrapover framework extensions were reduced compared with the removal of fingerlike locating extensions. In conclusion, care should be exercised when the locating extensions of resin-bonded retainers are removed with high-speed dental handpieces.
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Affiliation(s)
- B J Millar
- Department of Conservative Dentistry, King's College School of Medicine and Dentistry, London, United Kingdom
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38
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Davies BR, Barraclough R, Rudland PS. Induction of metastatic ability in a stably diploid benign rat mammary epithelial cell line by transfection with DNA from human malignant breast carcinoma cell lines. Cancer Res 1994; 54:2785-93. [PMID: 8168111] [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: 01/29/2023]
Abstract
Transfection of the stably diploid rat mammary epithelial cell line, Rama 37, which yields nonmetastasizing, adenomatous tumors in syngeneic rats with HindIII-fragmented DNA from malignant or nonmalignant human breast epithelial cell lines and the drug-resistance plasmid pSV2neo, yields transformants with a frequency of 10(-4) to 10(-5). The resultant cell lines form tumors with varying frequencies when injected s.c. into the mammary fat pads of syngeneic rats. Cells transfected with DNA from the malignant human breast carcinoma cell line, Ca2-83, or DNA from the human pleural effusion-derived cell lines, MCF-7 or ZR-75-1, yield transformants which metastasize to lungs and/or lymph nodes at high frequency, whereas transfection of HindIII-fragmented DNA from nonmetastatic human mammary epithelial cell lines, transfection of the drug-resistance plasmid pSV2neo alone, or nonspecific DNA such as salmon sperm DNA fails to yield transformants expressing the metastatic phenotype. Transfectants which metastasized were reestablished in culture and reinjected into syngeneic rats to confirm their metastatic properties. These transfectants yield rapidly growing tumors with reduced latent periods, which give rise to significant numbers of metastases. The karyotype of selected transfectants after passage in vivo remains stably diploid. Hybridization of a 32P-labeled oligonucleotide probe specific for the human Alu family of sequences to DNA from these transfectants reveals the presence of human-specific DNA sequences integrated into the genome. It is suggested that transfection of specific genomic DNA sequences from the malignant human cell lines can induce the metastatic phenotype in the nonmetastatic Rama 37 cell line in a genetically dominant manner, whereas genomic DNA from the nonmetastatic cells cannot confer metastatic properties to the Rama 37 cell line.
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Affiliation(s)
- B R Davies
- Department of Biochemistry, University of Liverpool, United Kingdom
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39
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Abstract
A syngeneic, immunocompetent rat mammary model has been employed to investigate the molecular basis of the metastatic phenotype. Transfection of the benign rat mammary epithelial cell line Rama 37 with the gene for p9Ka; a small, rat, calcium-binding protein or DNA from metastatic human cell lines derived from a primary breast carcinoma or a pleural effusion yields transfectants with metastatic capabilities. Transfection of DNA from a benign human mammary cell line, a plasmid containing a cDNA for the human basic fibroblast growth factor (bFGF) gene, or the oncogene EJ-ras-1, fails to yield any transfectants expressing the metastatic phenotype.
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Affiliation(s)
- B R Davies
- Biochemistry Department, University of Liverpool
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40
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Davies BR, Davies MP, Gibbs FE, Barraclough R, Rudland PS. Induction of the metastatic phenotype by transfection of a benign rat mammary epithelial cell line with the gene for p9Ka, a rat calcium-binding protein, but not with the oncogene EJ-ras-1. Oncogene 1993; 8:999-1008. [PMID: 8455951] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The rat mammary epithelial cell line, Rama 37, yields benign, non-metastasizing adenomatous tumours in syngeneic Wistar-Furth rats. Transfection of this line with a drug resistance plasmid containing both the gene for resistance to Geneticin (neo) and the gene for p9Ka (pSV2neo-p9Ka), a rat calcium-binding protein, or with a similar plasmid containing neo and the oncogene EJ-ras-1 (pSV2neo-ras) yields drug-resistant transformants that express high levels of the p9Ka or EJ-ras-1 mRNAs and proteins. These transfected cells all produce tumours when injected at subcutaneous sites with a shorter median latent period than the tumours produced by the parental untransfected Rama 37 cells in syngeneic hosts. Cells transfected with pSV2neo-p9Ka yield a higher incidence of tumours than untransfected Rama 37 cells, many of which metastasize to lungs and/or lymph nodes in syngeneic rats. However, cells transfected with pSV2-neo-ras or pSV2neo plasmid alone yield tumours that fail to metastasize. Immunofluorescent studies suggest an association of p9Ka with the cytoskeleton, as depicted by F-actin staining with the reagent phalloidin. It is suggested that the transfection of copies of the gene for the rat calcium-binding protein p9Ka can enhance the tumorigenic potential and induce the metastatic phenotype in this rat mammary model, whereas transfection of control plasmid DNA or the oncogene EJ-ras-1 fails to induce the metastatic phenotype, although EJ-ras-1 transfectants, like those containing p9Ka, possess increased growth properties in vivo.
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Affiliation(s)
- B R Davies
- Biochemistry Department, University of Liverpool, UK
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41
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Abstract
Composite resin has such good aesthetic qualities that it is often difficult to identify the tooth-restoration interface, yet this is particularly important should the material require complete removal. Following the in-vitro removal of direct and indirect composite resin restorations from Class II cavities significant changes in cavity size and shape were recorded. Thirty-eight cavities were studied from both occlusal and proximal aspects and the final cavity size was compared to the original cavity. There was a significant increase in cavity size with a mean increase of 37% for the direct composite cavities and 35% for the indirect cavities, although the range of values is large. Following restoration removal, occlusal surfaces were seen to increase in 71% of teeth and proximal surfaces in 75% of teeth. There was no significant difference between the results for direct and indirect composite restorations. Occlusal dovetails and cavity undercuts were created in cavities which did not contain these features initially.
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Affiliation(s)
- B J Millar
- Department of Conservative Dentistry, King's College School of Medicine and Dentistry, Denmark Hill, London
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Leyland-Jones B, Davies BR, Clagett-Carr K, Shoemaker D, Macfarlane D, Fortner C, O'Dwyer PJ, Sarosy G, Foster BJ, Chun HG. Patient treatment on a compassionate basis: documentation of high adverse drug reaction rate. Ann Oncol 1992; 3:59-62. [PMID: 1606071 DOI: 10.1093/oxfordjournals.annonc.a058072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [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: 12/27/2022] Open
Abstract
The special exception mechanism was established by the Division of Cancer Treatment (DCT), National Cancer Institute (NCI), for the provision of anticancer drugs not yet approved by the Food and Drug Administration (FDA) to patients on a compassionate basis. Strict guidelines have been established for the distribution of drugs through this mechanism and for the reporting of adverse drug reactions (ADRs) with investigational drugs. These guidelines have been used to format the data base which is maintained on all ADRs submitted by investigators. In this paper, the incidence of ADRs with the eleven investigational drugs most frequently administered on special exception protocols was determined for a twelve month time period, January 1, 1985 through December 31, 1985. On special exception protocols, the overall incidence rate of ADRs was significantly greater than that seen on research protocols for the time period. For three drugs, Methyl-G, DBD, and AMSA, the ADR incidence rate was seven to fifteen-fold greater on special exception protocols than on research protocols. In an analysis of all ADRs submitted to the FDA for the twelve months time period, no difference was found in the frequency of distribution of either types of adverse effects or the causal assessments of ADRs on special exception and research protocols.
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Affiliation(s)
- B Leyland-Jones
- Investigational Drug Branch, National Cancer Institute, Bethesda, MD
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Davies BR. Congenital mesonephric nephroma. Arch Pathol Lab Med 1991; 115:975. [PMID: 1654874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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O'Keeffe JH, Palmer RW, Byren BA, Davies BR. The effects of impoundment on the physicochemistry of two contrasting southern african river systems. ACTA ACUST UNITED AC 1990. [DOI: 10.1002/rrr.3450050202] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Stewart BA, Davies BR. EFFECTS OF MACROPHYTE HARVESTING ON INVERTEBRATES ASSOCIATED WITHPOTAMOGETON PECTINATUSL. IN THE MARINA DA GAMA, ZANDVLEI, WESTERN CAPE. ACTA ACUST UNITED AC 1986. [DOI: 10.1080/00359198609520105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Abstract
In a referral perinatal center a detailed study was made of all the perinatal deaths that occurred during 1 year; they were analyzed according to primary diagnoses on the basis of a classification by R. L. Naeye which included the placenta. This method points to the areas in which special efforts at prevention should be made, and it should become a reliable basis for comparison.
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Davies BR, Fuentes C. Co-existing hydatidiform mole with a live fetus. Am J Obstet Gynecol 1984; 150:901-2. [PMID: 6507523 DOI: 10.1016/0002-9378(84)90481-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Abstract
Thirty-five placentas of small-for-dates infants were compared with control placentas of normally grown infants. They were small by weight, area, and volume and tended to have a marginal cord insertion; marginal cord insertion was associated with a thick cord, and central insertion, with a thin cord. When the two groups were compared, the first showed increased fibrinoid deposits and atherosis, more severe fetal abnormalities, and abnormal nutrition in the mother, together with a high incidence of preeclampsia. In the mothers of both groups, peak diastolic blood pressure was lower than that in the control group; additional factors leading to a probable reduction in placental blood flow were different in the two groups.
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