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Kahsar-Miller MD, Nixon C, Boots LR, Go RC, Azziz R. Prevalence of polycystic ovary syndrome (PCOS) in first-degree relatives of patients with PCOS. Fertil Steril 2001; 75:53-8. [PMID: 11163816 DOI: 10.1016/s0015-0282(00)01662-9] [Citation(s) in RCA: 219] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE To determine the rate of clinically evident polycystic ovary syndrome (PCOS) among first-degree female relatives within families with a proband affected by PCOS. DESIGN Clinical and biochemical evaluation of the mothers and sisters of 93 patients with PCOS. The diagnosis of PCOS was established by: [1] a history of oligomenorrhea, [2] clinical evidence (i.e., hirsutism) or biochemical evidence (i.e., elevated total or free T) of hyperandrogenism, and [3] the exclusion of related disorders. SETTING Tertiary care university. PATIENT(S) Patients with PCOS and their mothers and sisters. INTERVENTION(S) Interview, physical examination, and hormonal testing on blood samples were performed for all subjects. MAIN OUTCOME MEASURE(S) The presence of hirsutism and hyperandrogenemia was determined in the mothers and sisters of the patients with PCOS. RESULT(S) Of the 78 mothers and 50 sisters evaluated clinically, 19 (24%) and 16 (32%) were affected with PCOS, respectively. A higher rate of PCOS was observed when only premenopausal women not taking hormones (i.e., untreated) were considered (i.e., 35% of mothers and 40% of sisters), consistent with amelioration of symptoms with hormonal therapy or aging. These rates of PCOS are significantly higher than that observed in our general population (approximately 4%) and suggest the involvement of a major genetic component in the disorder. CONCLUSION(S) The rates of PCOS in mothers and sisters of patients with PCOS were 24% and 32%, respectively, although the risk was higher when considering untreated premenopausal women only.
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Clinical Trial |
24 |
219 |
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Sakr M, Angus J, Perrin J, Nixon C, Nicholl J, Wardrope J. Care of minor injuries by emergency nurse practitioners or junior doctors: a randomised controlled trial. Lancet 1999; 354:1321-6. [PMID: 10533859 DOI: 10.1016/s0140-6736(99)02447-2] [Citation(s) in RCA: 181] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND We aimed to assess the care and outcome of patients with minor injuries who were managed by a nurse practitioner or a junior doctor in our accident and emergency department. METHODS 1453 eligible patients, over age 16 years, who presented at our department with minor injuries were randomly assigned care by a nurse practitioner (n=704) or by a junior doctor (n=749). Each patient was first assessed by the nurse practitioner or junior doctor who did a clinical assessment; the assessments were transcribed afterwards to maintain masked conditions. Patients were then assessed by an experienced accident and emergency physician (research registrar) who completed a research assessment, but took no part in the clinical management of the patient. A standard form was used to compare the clinical assessment of the nurse practitioner or junior doctor with the assessment of the research registrar. The primary outcome measure was the adequacy of care (history taking, examination of patient, interpretation of radiographs, treatment decision, advice, and follow-up). FINDINGS Compared with the rigorous standard of the experienced accident and emergency research registrar, nurse practitioners and junior doctors made clinically important errors in 65 (9.2%) of 704 patients and in 80 (10.7%) of 749 patients, respectively. This difference was not significant. The nurse practitioners were better than junior doctors at recording medical history and fewer patients seen by a nurse practitioner had to seek unplanned follow-up advice about their injury. There were no significant differences between nurse practitioners and junior doctors in the accuracy of examination, adequacy of treatment, planned follow-up, or requests for radiography. Interpretation of radiographs was similar in the two groups. INTERPRETATION Properly trained accident and emergency nurse practitioners, who work within agreed guidelines can provide care for patients with minor injuries that is equal or in some ways better than that provided by junior doctors.
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Clinical Trial |
26 |
181 |
3
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Muller PAJ, Trinidad AG, Timpson P, Morton JP, Zanivan S, van den Berghe PVE, Nixon C, Karim SA, Caswell PT, Noll JE, Coffill CR, Lane DP, Sansom OJ, Neilsen PM, Norman JC, Vousden KH. Mutant p53 enhances MET trafficking and signalling to drive cell scattering and invasion. Oncogene 2013; 32:1252-65. [PMID: 22580601 PMCID: PMC3592945 DOI: 10.1038/onc.2012.148] [Citation(s) in RCA: 160] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 03/14/2012] [Indexed: 12/12/2022]
Abstract
Tumour-derived mutant p53 proteins promote invasion, in part, by enhancing Rab coupling protein (RCP)-dependent receptor recycling. Here we identified MET as an RCP-binding protein and showed that mutant p53 promoted MET recycling. Mutant p53-expressing cells were more sensitive to hepatocyte growth factor, the ligand for MET, leading to enhanced MET signalling, invasion and cell scattering that was dependent on both MET and RCP. In cells expressing the p53 family member TAp63, inhibition of TAp63 also lead to cell scattering and MET-dependent invasion. However, in cells that express very low levels of TAp63, the ability of mutant p53 to promote MET-dependent cell scattering was independent of TAp63. Taken together, our data show that mutant p53 can enhance MET signalling to promote cell scattering and invasion through both TAp63-dependent and -independent mechanisms. MET has a predominant role in metastatic progression and the identification of mechanisms through which mutations in p53 can drive MET signalling may help to identify and direct therapy.
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research-article |
12 |
160 |
4
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Hetzel MR, Nixon C, Edmondstone WM, Mitchell DM, Millard FJ, Nanson EM, Woodcock AA, Bridges CE, Humberstone AM. Laser therapy in 100 tracheobronchial tumours. Thorax 1985; 40:341-5. [PMID: 4023988 PMCID: PMC460064 DOI: 10.1136/thx.40.5.341] [Citation(s) in RCA: 99] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
One hundred patients with tracheobronchial tumours were treated with the neodymium YAG (yttrium-aluminium-garnet) or argon laser for symptoms of airways obstruction caused by tumour (59 cases), complete collapse of a lung (17 cases), or recurrent haemoptysis (24 cases). Seventy four of them had relapsed or failed to respond to radiotherapy or chemotherapy and all were inoperable. Objective improvement in results of lung function tests or haemoptysis diary charts was seen in 37 patients with airways obstruction (63%), five (29%) with collapsed lung, and 14 (58%) with haemoptysis. Overall, 68 patients had symptomatic benefit and there was objective improvement in 56. Two deaths occurred in 288 treatment sessions both occurring as a result of asphyxia from minor haemorrhage in patients with advanced cylindromas and critical narrowing of the trachea or single remaining bronchus. In suitable patients with intraluminal tumour laser phototherapy is a valuable addition to conventional treatment.
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research-article |
40 |
99 |
5
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Wyatt R, Desjardin E, Olshevsky U, Nixon C, Binley J, Olshevsky V, Sodroski J. Analysis of the interaction of the human immunodeficiency virus type 1 gp120 envelope glycoprotein with the gp41 transmembrane glycoprotein. J Virol 1997; 71:9722-31. [PMID: 9371638 PMCID: PMC230282 DOI: 10.1128/jvi.71.12.9722-9731.1997] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) gp120 exterior envelope glycoprotein interacts with the viral receptor (CD4) and with the gp41 transmembrane envelope glycoprotein. To study the interaction of the gp120 and gp41 envelope glycoproteins, we compared the abilities of anti-gp120 monoclonal antibodies to bind soluble gp120 and a soluble glycoprotein, sgp140, that contains gp120 and gp41 exterior domains. The occlusion or alteration of a subset of gp120 epitopes on the latter molecule allowed the definition of a gp41 "footprint" on the gp120 antibody competition map. The occlusion of these epitopes on the sgp140 glycoprotein was decreased by the binding of soluble CD4. The gp120 epitopes implicated in the interaction with the gp41 ectodomain were disrupted by deletions of the first (C1) and fifth (C5) conserved gp120 regions. These deletions did not affect the integrity of the discontinuous binding sites for CD4 and neutralizing monoclonal antibodies. Thus, the gp41 interface on the HIV-1 gp120 glycoprotein, which elicits nonneutralizing antibodies, can be removed while retaining immunologically desirable gp120 structures.
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research-article |
28 |
85 |
6
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Gibson EL, Kreichauf S, Wildgruber A, Vögele C, Summerbell CD, Nixon C, Moore H, Douthwaite W, Manios Y. A narrative review of psychological and educational strategies applied to young children's eating behaviours aimed at reducing obesity risk. Obes Rev 2012; 13 Suppl 1:85-95. [PMID: 22309067 DOI: 10.1111/j.1467-789x.2011.00939.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Strategies to reduce risk of obesity by influencing preschool children's eating behaviour are reviewed. The studies are placed in the context of relevant psychological processes, including inherited and acquired preferences, and behavioural traits, such as food neophobia, 'enjoyment of food' and 'satiety responsiveness'. These are important influences on how children respond to feeding practices, as well as predictors of obesity risk. Nevertheless, in young children, food environment and experience are especially important for establishing eating habits and food preferences. Providing information to parents, or to children, on healthy feeding is insufficient. Acceptance of healthy foods can be encouraged by five to ten repeated tastes. Recent evidence suggests rewarding healthy eating can be successful, even for verbal praise alone, but that palatable foods should not be used as rewards for eating. Intake of healthier foods can be promoted by increasing portion size, especially in the beginning of the meal. Parental strategies of pressuring to eat and restriction do not appear to be causally linked to obesity, but are instead primarily responses to children's eating tendencies and weight. Moderate rather than frequent restriction may improve healthy eating in children. Actively positive social modelling by adults and peers can be effective in encouraging healthier eating.
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Review |
13 |
77 |
7
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Klein MD, Andrews AF, Wesley JR, Toomasian J, Nixon C, Roloff D, Bartlett RH. Venovenous perfusion in ECMO for newborn respiratory insufficiency. A clinical comparison with venoarterial perfusion. Ann Surg 1985; 201:520-6. [PMID: 3977454 PMCID: PMC1250743 DOI: 10.1097/00000658-198504000-00019] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) has been successful in the treatment of newborns less than 1 week of age and greater than 2000 gm birthweight with respiratory failure resistant to current medical and surgical management. While VA ECMO supports the heart as well as the lungs, it has the disadvantage of requiring carotid artery ligation and the possibility of perfusing air bubbles or particles into the arterial tree. We have treated 11 newborns with respiratory failure with venovenous (VV) ECMO returning the oxygenated blood to a cannula in the distal iliac vein. We compared these patients with 16 patients treated during the same period of time with VA ECMO. Three of the 11 VV patients required conversion to VA ECMO because of inadequate oxygenation and unstable hemodynamic situations. Ten of the 11 VV patients survived. Eleven of the 16 VA patients survived. The better survival in these patients treated with VV ECMO is attributed to their more favorable initial condition compared to patients treated with VA ECMO. The disadvantages of VV ECMO include a longer operative time to place the cannulas, groin wound problems, and persistent leg swelling along with the necessity to convert some patients to VA ECMO. Although this experience demonstrates that newborns with severe respiratory failure can be supported with VV ECMO, the complications and lack of practical advantages over VA lead us to recommend VA ECMO for routine clinical use at present.
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research-article |
40 |
66 |
8
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Huels DJ, Bruens L, Hodder MC, Cammareri P, Campbell AD, Ridgway RA, Gay DM, Solar-Abboud M, Faller WJ, Nixon C, Zeiger LB, McLaughlin ME, Morrissey E, Winton DJ, Snippert HJ, van Rheenen J, Sansom OJ. Wnt ligands influence tumour initiation by controlling the number of intestinal stem cells. Nat Commun 2018; 9:1132. [PMID: 29556067 PMCID: PMC5859272 DOI: 10.1038/s41467-018-03426-2] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 02/13/2018] [Indexed: 01/08/2023] Open
Abstract
Many epithelial stem cell populations follow a pattern of stochastic stem cell divisions called 'neutral drift'. It is hypothesised that neutral competition between stem cells protects against the acquisition of deleterious mutations. Here we use a Porcupine inhibitor to reduce Wnt secretion at a dose where intestinal homoeostasis is maintained despite a reduction of Lgr5+ stem cells. Functionally, there is a marked acceleration in monoclonal conversion, so that crypts become rapidly derived from a single stem cell. Stem cells located further from the base are lost and the pool of competing stem cells is reduced. We tested whether this loss of stem cell competition would modify tumorigenesis. Reduction of Wnt ligand secretion accelerates fixation of Apc-deficient cells within the crypt leading to accelerated tumorigenesis. Therefore, ligand-based Wnt signalling influences the number of stem cells, fixation speed of Apc mutations and the speed and likelihood of adenoma formation.
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research-article |
7 |
65 |
9
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Parkes A, Henderson M, Wight D, Nixon C. Is parenting associated with teenagers' early sexual risk-taking, autonomy and relationship with sexual partners? PERSPECTIVES ON SEXUAL AND REPRODUCTIVE HEALTH 2011; 43:30-40. [PMID: 21388503 PMCID: PMC3437472 DOI: 10.1363/4303011] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
CONTEXT Extensive research has explored the relationship between parenting and teenagers' sexual risk-taking. Whether parenting is associated with wider aspects of teenagers' capacity to form satisfying sexual relationships is unknown. METHODS Self-reported data were collected in 2007 from 1,854 students, whose average age was 15.5 years, in central Scotland. Multivariate analyses examined associations between parenting processes and sexual outcomes (delayed first intercourse, condom use and several measures reflecting the context or anticipated context of first sex). RESULTS Parental supportiveness was positively associated with all outcomes (betas, 0.1-0.4), and parental values restricting intercourse were positively associated with all outcomes except condom use (0.1-0.5). Parental monitoring was associated only with delayed intercourse (0.2) and condom use (0.2); parental rules about TV content were associated with delayed intercourse (0.7) and expecting sex in a relationship, rather than casually (0.8). Frequency of parental communication about sex and parental values endorsing contraceptive use were negatively associated with teenagers' delayed intercourse (-0.5 and -0.3, respectively), and parents' contraceptive values were negatively associated with teenagers' expecting sex in a relationship (-0.5). Associations were partly mediated by teenagers' attitudes, including value placed on having sex in a relationship. CONCLUSIONS Parents may develop teenagers' capacity for positive and safe early sex by promoting skills and values that build autonomy and encourage sex only within a relationship. Interventions should promote supportive parenting and transmission of values, avoid mixed messages about abstinence and contraception, and acknowledge that teenagers may learn more indirectly than directly from parents about sex.
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research-article |
14 |
59 |
10
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Mitchell MA, Hungeford LL, Nixon C, Esker T, Sullivan J, Koerkenmeier R, Dubey JP. Serologic survey for selected infectious disease agents in raccoons from Illinois. J Wildl Dis 1999; 35:347-55. [PMID: 10231761 DOI: 10.7589/0090-3558-35.2.347] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The determination of serologic titers to infectious organisms is a valuable tool for quantitating exposure to disease organisms. Raccoons (Procyon lotor) were live-trapped from September 1989 to October 1993 and samples collected from two distinct locations in west-central Illinois (USA); a state recreational facility (Park) and privately owned farming property (Farm). Sera were submitted for testing Leptospira interrogans (serovars bratislava, canicola, grippotyphosa, hardjo, icterohemmorhagiae, and pomona), canine distemper virus (CDV), pseudorabies virus (PV), and Toxoplasma gondii. Two-hundred and twenty-two (48%) of 459 raccoons were seropositive for L. interrogans. Eighty-five (23%) out of 368 raccoons were seropositive for canine distemper virus. Eighty-two (17%) of 479 raccoons raccoons were seropositive for pseudorabies virus. One hundred and eight-four (49%) of 379 raccoons were seropositive for T. gondii. A significant difference (P < 0.05) in seroprevalence for L. interrogans between the park (43%) and farm (52%) areas was found. A correlation between increasing age and seroprevalence was found for L. interrogans, CDV, PV, and T. gondii. Furthermore, there was a significant difference in seroprevalence for T. gondii during the spring trapping seasons (73%), when compared with the fall (33%). This type of information on exposure to infectious agents is important for developing control programs to manage raccoon-human and raccoon-domestic animals interactions.
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26 |
51 |
11
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George PJ, Garrett CP, Nixon C, Hetzel MR, Nanson EM, Millard FJ. Laser treatment for tracheobronchial tumours: local or general anaesthesia? Thorax 1987; 42:656-60. [PMID: 3686456 PMCID: PMC460902 DOI: 10.1136/thx.42.9.656] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Ninety seven patients with tracheobronchial tumours have been treated with the neodymium yttrium-aluminium-garnet (Nd YAG) laser over a period of 33 months. Fifty one of these patients were treated under local anaesthesia and 46 under general anaesthesia. The results obtained with the two methods have been compared retrospectively. The numbers of patients responding to treatment, the magnitude of the response, and the duration of palliation were similar in the two groups; significantly more treatment sessions, however, were required during each course of treatment under local anaesthesia. This advantage of general anaesthesia was thought to arise from the ability to continue treatment for longer and with greater efficiency. The use of the rigid bronchoscope with jet ventilation under general anaesthesia was also thought to provide better control of the airway and to allow more efficient clearance of blood and mucus. Two operative deaths occurred under local anaesthesia, when bleeding led to asphyxiation, but none have occurred under general anaesthesia. Treatment under general anaesthesia is not, however, without risk and is potentially hazardous in patients with severe chronic hypoxic lung disease.
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research-article |
38 |
46 |
12
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Nixon C, Hirsch NP, Ormerod IE, Johnson G. Nuclear magnetic resonance. Its implications for the anaesthetist. Anaesthesia 1986; 41:131-7. [PMID: 3953985 DOI: 10.1111/j.1365-2044.1986.tb13166.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The theory and practice of clinical nuclear magnetic resonance (NMR) imaging is reviewed. Problems which the anaesthetist will encounter are considered, and recommendations are proposed. Possible uses of NMR in anaesthesia are discussed.
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39 |
39 |
13
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Yuan ZQ, Gault EA, Gobeil P, Nixon C, Campo MS, Nasir L. Establishment and characterization of equine fibroblast cell lines transformed in vivo and in vitro by BPV-1: model systems for equine sarcoids. Virology 2008; 373:352-61. [PMID: 18191170 DOI: 10.1016/j.virol.2007.11.037] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Revised: 11/08/2007] [Accepted: 11/30/2007] [Indexed: 11/28/2022]
Abstract
It is now widely recognized that BPV-1 and less commonly BPV-2 are the causative agents of equine sarcoids. Here we present the generation of equine cell lines harboring BPV-1 genomes and expressing viral genes. These lines have been either explanted from sarcoid biopsies or generated in vitro by transfection of primary fibroblasts with BPV-1 DNA. Previously detected BPV-1 genome variations in equine sarcoids are also found in sarcoid cell lines, and only variant BPV-1 genomes can transform equine cells. These equine cell lines are morphologically transformed, proliferate faster than parental cells, have an extended life span and can grow independently of substrate. These characteristics are more marked the higher the level of viral E5, E6 and E7 gene expression. These findings confirm that the virus has an active role in the induction of sarcoids and the lines will be invaluable for further studies on the role of BPV-1 in sarcoid pathology.
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Research Support, Non-U.S. Gov't |
17 |
37 |
14
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Kestin IG, Harvey PB, Nixon C. Psychomotor recovery after three methods of sedation during spinal anaesthesia. Br J Anaesth 1990; 64:675-81. [PMID: 2116156 DOI: 10.1093/bja/64.6.675] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
In a double-blinded study, we have investigated psychomotor recovery after three sedation schemes during spinal anaesthesia for transurethral resection of prostate. Thirty-nine patients were allocated randomly to receive i.v. midazolam only, i.v. midazolam with antagonism by flumazenil or an infusion of propofol. The psychomotor tests were of long and short term memory, critical flicker fusion threshold, attention and concentration, cognition, mental arithmetic, and sedation and anxiety levels, and were performed before operation and at 30 min, 60 min, 2 h and 24 h after operation. Free recall of a picture learning task was the most sensitive test, showing a significant impairment in all groups, persisting for more than 2 h. Propofol was associated with the most rapid recovery and least impairment compared with preoperative baseline. Performance improved in all the tests after antagonism with flumazenil, but was still significantly impaired compared with baseline in tests of picture recall and letter deletion. Significant decreases in performance in all tests were detected 1 h after flumazenil. No increase in anxiety was recorded after flumazenil. We conclude that infusion of propofol is the technique with the most rapid recovery, while only brief and incomplete antagonism of the effects of midazolam may be expected with flumazenil.
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Clinical Trial |
35 |
34 |
15
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Rosenfeldt MT, Bell LA, Long JS, O'Prey J, Nixon C, Roberts F, Dufès C, Ryan KM. E2F1 drives chemotherapeutic drug resistance via ABCG2. Oncogene 2014; 33:4164-72. [PMID: 24276245 DOI: 10.1038/onc.2013.470] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 09/12/2013] [Accepted: 10/06/2013] [Indexed: 12/18/2022]
Abstract
Multidrug resistance is a major barrier against successful chemotherapy, and this has been shown in vitro to be often caused by ATP-binding cassette (ABC) transporters. These transporters are frequently overexpressed in human cancers and confer an adverse prognosis in many common malignancies. The genetic factors, however, that initiate their expression in cancer are largely unknown. Here we report that the major multidrug transporter ABCG2 (BCRP/MXR) is directly and specifically activated by the transcription factor E2F1--a factor perturbed in the majority of human cancers. E2F1 regulates ABCG2 expression in multiple cell systems, and, importantly, we have identified a significant correlation between elevated E2F1 and ABCG2 expression in human lung cancers. We show that E2F1 causes chemotherapeutic drug efflux both in vitro and in vivo via ABCG2. Furthermore, the E2F1-ABCG2 axis suppresses chemotherapy-induced cell death that can be restored by the inhibition of ABCG2. These findings therefore identify a new axis in multidrug resistance and highlight a radical new function of E2F1 that is relevant to tumor therapy.
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11 |
33 |
16
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Mellor PJ, Haugland S, Smith KC, Powell RM, Archer J, Scase TJ, Villiers EJ, McNeil PE, Nixon C, Knott C, Fournier D, Murphy S, Polton GA, Belford C, Philbey AW, Argyle DJ, Herrtage ME, Day MJ. Histopathologic, Immunohistochemical, and Cytologic Analysis of Feline Myeloma-Related Disorders: Further Evidence for Primary Extramedullary Development in the Cat. Vet Pathol 2008; 45:159-73. [DOI: 10.1354/vp.45-2-159] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Feline myeloma-related disorders (MRD) are rare neoplasms of plasma cells. The multistep transformation model of myeloma in humans is based on the premise that plasma cells undergo neoplastic transformation primarily within the intramedullary compartment and that over time they become poorly differentiated and metastasize to extramedullary locations. Historically, diagnostic criteria used for human multiple myeloma have been applied to the cat, with the assumption that feline MRD commonly arises in the intramedullary compartment. Our objectives were to describe the features of feline MRD confirmed by cytology, histopathology, histochemistry, and immunohistochemistry and to categorize these tumors. A priori hypotheses were 1) tumor category predicts survival and 2) cats with well-differentiated tumors commonly have extramedullary involvement in contrast to human myeloma patients. This multicenter, retrospective study identified 26 MRD cases. There was good agreement between histopathologic and cytologic tumor categorization. Histochemistry and immunohistochemistry were shown to be valuable adjunct tests in the diagnosis of MRD. Cats with well-differentiated tumors had increased median survival relative to those with poorly differentiated tumors (254 versus 14 days). We have reported that marked extramedullary involvement at initial clinical presentation is significantly more common in the cat than in human MRD patients. In this study, we demonstrate that cats with well-differentiated tumors more commonly have extramedullary involvement than human myeloma patients with well-differentiated tumors (90% versus 20%, P < 0.0002). These results contrast strongly with the human myeloma model of primary intramedullary neoplastic transformation and suggest that primary extramedullary neoplastic transformation may be more common in feline MRD.
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32 |
17
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Roberts NJ, Kidd L, Dougall N, Patel IS, McNarry S, Nixon C. Measuring patient activation: The utility of the Patient Activation Measure within a UK context-Results from four exemplar studies and potential future applications. PATIENT EDUCATION AND COUNSELING 2016; 99:1739-1746. [PMID: 27217050 DOI: 10.1016/j.pec.2016.05.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 05/05/2016] [Accepted: 05/08/2016] [Indexed: 06/05/2023]
Abstract
OBJECTIVE Patient activation can be measured using the Patient Activation Measure (PAM) developed by Hibbard et al., however, little is known about the uses of the PAM in research and in practice. This study aims to explore its differing utility in four UK exemplar sites. METHODS Data from four exemplars in a range of health settings with people living with long-term conditions (i.e. stroke or COPD) were evaluated. PAM scores were described and explored in relation to clinical and sociodemographic variables and outcome measures. RESULTS PAM scores illustrated that most with COPD or stroke reported PAM levels of 3 or 4, indicating that they are engaging, but may need help to sustain their scores. The exemplars illustrate the utility of, and potential issues involved in, using PAM as a process/outcome measure to predict activation and the effectiveness of interventions, and as a tool to inform tailoring of targeted interventions. CONCLUSIONS The PAM tool has been shown to be useful as an outcome measure, a screening tool to tailor education, or a quality indicator for delivery of care. PRACTICE IMPLICATIONS However good demographic and patient history are needed to substantiate PAM scores. Further work is needed to monitor PAM prospectively.
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28 |
18
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Roos-Serote M, Vasavada AR, Kamp L, Drossart P, Irwin P, Nixon C, Carlson RW. Proximate humid and dry regions in Jupiter's atmosphere indicate complex local meteorology. Nature 2000; 405:158-60. [PMID: 10821265 DOI: 10.1038/35012023] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Models of Jupiter's formation and structure predict that its atmosphere is enriched in oxygen, relative to the Sun, and that consequently water clouds should be present globally near the 5-bar pressure level. Past attempts to confirm these predictions have led to contradictory results; in particular, the Galileo probe revealed a very dry atmosphere at the entry site, with no significant clouds at depths exceeding the 2-bar level. Although the entry site was known to be relatively cloud-free, the contrast between the observed local dryness and the expected global wetness was surprising. Here we analyse near-infrared (around 5 microm) observations of Jupiter, a spectral region that can reveal the water vapour abundance and vertical cloud structure in the troposphere. We find that humid and extremely dry regions exist in close proximity, and that some humid regions are spatially correlated with bright convective clouds extending from the deep water clouds to the visible atmosphere.
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Going JJ, Nixon C, Dornan ES, Boner W, Donaldson MM, Morgan IM. Aberrant expression of TopBP1 in breast cancer. Histopathology 2007; 50:418-24. [PMID: 17448016 DOI: 10.1111/j.1365-2559.2007.02622.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
AIMS The TopBP1 protein includes eight BRCT domains (originally identified in BRCA1) and has homology with BRCA1 over the carboxyl terminal half of the protein. The aim of this study was to determine whether TopBP1 is aberrantly expressed in breast cancer. METHODS AND RESULTS Sixty-one breast carcinomas from an unselected consecutive patient cohort were studied along with 12 samples of breast tissue from cosmetic breast reduction surgery; these were analysed immunohistochemically for TopBP1 expression using a rabbit polyclonal antibody. This antibody was validated in immunoprecipitation and immunofluorescence experiments. Immunohistochemical analysis demonstrated that TopBP1 was expressed almost exclusively in the nuclei of the normal breast epithelium. However, in a significant number of breast carcinomas TopBP1 was aberrantly expressed, as it was detected in the cytoplasm and nucleus of some tumours and exclusively in the cytoplasm of others. In two out of 61 carcinomas investigated, no TopBP1 expression was detected. CONCLUSIONS For the first time this report demonstrates aberrant expression of the TopBP1 protein in breast carcinoma. We propose TOPBP1 as a breast cancer susceptibility gene.
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Research Support, Non-U.S. Gov't |
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Henderson M, Wight D, Nixon C, Hart G. Retaining young people in a longitudinal sexual health survey: a trial of strategies to maintain participation. BMC Med Res Methodol 2010; 10:9. [PMID: 20109221 PMCID: PMC2837673 DOI: 10.1186/1471-2288-10-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2008] [Accepted: 01/28/2010] [Indexed: 11/24/2022] Open
Abstract
Background There is an increasing trend towards lower participation in questionnaire surveys. This reduces representativeness, increases costs and introduces particular challenges to longitudinal surveys, as researchers have to use complex statistical techniques which attempt to address attrition. This paper describes a trial of incentives to retain longitudinal survey cohorts from ages 16 to 20, to question them on the sensitive topic of sexual health. Methods A longitudinal survey was conducted with 8,430 eligible pupils from two sequential year groups from 25 Scottish schools. Wave 1 (14 years) and Wave 2 (16 years) were conducted largely within schools. For Wave 3 (18 years), when everyone had left school, the sample was split into 4 groups that were balanced across predictors of survey participation: 1) no incentive; 2) chance of winning one of twenty-five vouchers worth £20; 3) chance of winning one £500 voucher; 4) a definite reward of a £10 voucher sent on receipt of their completed questionnaire. Outcomes were participation at Wave 3 and two years later at Wave 4. Analysis used logistic regression and adjusted for clustering at school level. Results The only condition that had a significant and beneficial impact for pupils was to offer a definite reward for participation (Group 4). Forty-one percent of Group 4 participated in Wave 3 versus 27% or less for Groups 1 to 3. At Wave 4, 35% of Group 4 took part versus 25% or less for the other groups. Similarly, 22% of Group 4 participated in all four Waves of the longitudinal study, whereas for the other three groups it was 16% or less that participated in full. Conclusions The best strategy for retaining all groups of pupils and one that improved retention at both age 18 and age 20 was to offer a definite reward for participation. This is expensive, however, given the many benefits of retaining a longitudinal sample, we recommend inclusion of this as a research cost for cohort and other repeat-contact studies.
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Long S, Argyle DJ, Nixon C, Nicholson I, Botteron C, Olby N, Platt S, Smith K, Rutteman GR, Grinwis GCM, Nasir L. Telomerase reverse transcriptase (TERT) expression and proliferation in canine brain tumours. Neuropathol Appl Neurobiol 2006; 32:662-73. [PMID: 17083480 DOI: 10.1111/j.1365-2990.2006.00776.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Telomerase is a ribonucleoprotein enzyme complex that synthesizes telomere DNA. It is detected in 85-90% of malignant tumours in humans, but not in most somatic cells. Because telomerase plays a critical role in cell immortality, it represents an important target for anticancer therapies. We have previously shown that the dog is a potentially useful model for evaluating telomerase-based therapeutics. In this present study we analysed 93 canine brain tumours for telomerase reverse transcriptase (TERT) expression by immunohistochemistry. TERT immunoreactivity was detected in 16 of 50 grade 1 (32%) and 29 of 43 grade 2 tumours (67.4%), demonstrating a statistically significant association with histological grade (P = 0.00012). A subset of 51 tumours was also assessed for MIB-1 expression. The MIB-1 labelling index (LI) was found to correlate significantly with tumour grade, with a mean MIB-1 LI of 1.5% for grade 1 tumours, as compared with a mean MIB-1 LI of 21.7% for grade 2 tumours (P << 0.001). The MIB-1 LI was also significantly associated with TERT expression in all brain tumours (P << 0.001). These data further support the dog as a model for the preclinical development of telomerase-based therapeutics in brain tumours.
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Knottenbelt C, Mellor D, Nixon C, Thompson H, Argyle DJ. Cohort study of COX-1 and COX-2 expression in canine rectal and bladder tumours. J Small Anim Pract 2006; 47:196-200. [PMID: 16573762 DOI: 10.1111/j.1748-5827.2006.00094.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To determine the role that cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) play in malignant transformation in canine transitional cell carcinoma and rectal tumours. METHODS Histological sections of 21 canine rectal adenocarcinomas and 18 canine transitional cell carcinomas were stained for COX-1 and COX-2. Mann-Whitney non-parametric tests were applied to determine if there was any relationship between the percentage of cells expressing COX-1 or COX-2, and between COX-1 and COX-2 staining intensity and age, breed or sex. RESULTS For rectal adenocarcinomas, 19.0 per cent of the sections were negative for COX-1 and COX-2. A further 38.1 per cent of the sections were negative for COX-2 but positive for COX-1, and 38.1 per cent of the sections had rare or occasional single cells positive for COX-2. No significant differences were found in COX staining when compared with age, breed or sex. For transitional cell carcinomas, all of the sections were positive for COX-1 and COX-2. For COX-2 staining, 16.7 per cent had more than 30 per cent positive cells. For COX-1 staining, 38.9 per cent had more than 30 per cent positive cells. There was a significant increase in the percentage of COX-1 positive cells in small breed dogs (P = 0.0337). CLINICAL SIGNIFICANCE The variations in COX expression reported in this study may explain the differences in the clinical response of transitional cell carcinomas and rectal adenocarcinomas following treatment with non-steroidal anti-inflammatory drugs.
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Renwick MG, Argyle DJ, Long S, Nixon C, Gault EA, Nasir L. Telomerase activity and telomerase reverse transcriptase catalytic subunit expression in canine lymphoma: correlation with Ki67 immunoreactivity. Vet Comp Oncol 2009; 4:141-50. [PMID: 19754811 DOI: 10.1111/j.1476-5829.2006.00103.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Increased telomerase activity (TA) has been found in human and canine solid tumours, stem cells and somatic tissues with enhanced proliferative potential. The relationship between TA in normal and malignant lymphoid tissues remains unclear. The TA and the expression of canine telomerase reverse transcriptase catalytic subunit (dogTERT) messenger RNA (mRNA) were analyzed in malignant lymph nodes from 30 dogs with lymphoma, from two dogs with non-neoplastic illness and from two clinically normal dogs, demonstrating a statistically significant difference between TA in lymphoma lymph nodes (n = 30) and normal nodes (n = 4) but no significant difference in dogTERT mRNA expression. In addition, the expression of telomerase reverse transcriptase catalytic subunit (TERT) protein and Ki67 was analyzed in malignant lymph nodes from 10 dogs with lymphoma and from two clinically normal dogs by immunohistochemistry. TERT expression was associated with Ki67 in all lymphoma nodes (n = 10), and differences were illustrated between TERT and Ki67 expression between lymphoma (n = 10) and non-lymphoma (n = 2) nodes. This data support further investigation of telomerase in canine haematopoietic neoplasia through large-scale prospective studies.
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Abstract
Administered the 1973 revision of the Henmon-Nelson and the WAIS to 100 psychiatric patients. The correlation of Henmon-Nelson raw scores with WAIS Full Scale scaled score was .83, which compared favorably with correlations run between several other short IQ tests and the WAIS in similar samples drawn from the same setting in earlier studies. However, the Henmon-Nelson did not appear able to estimate the WAIS IQs of low-intelligence Ss or aged persons with consistent accuracy. The validities of short IQ tests and current practices in the selection of WAIS surrogates were discussed.
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Dalsing MC, Kevorkian M, Raper B, Nixon C, Lalka SG, Cikrit DF, Unthank JL, Herring MB. An experimental collagen-impregnated Dacron graft: potential for endothelial seeding. Ann Vasc Surg 1989; 3:127-33. [PMID: 2527547 DOI: 10.1016/s0890-5096(06)62005-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
This study evaluates the potential for endothelial seeding of a collagen-impregnated Dacron graft with or without surface modifiers (fibronectin, heparin) to attach and retain these cells during flow. Human umbilical endothelial cells were harvested, cultured, labeled with Indium111-oxine and seeded onto 30 mm X 4 mm diameter grafts. Six graft surfaces were studied: 1) a collagen-impregnated Dacron graft, HemashieldR (C); 2) C + fibronectin (C + F); 3) C + heparin (C + H); 4) C + F + H; 5) HytrelR + F (Hyt + F); and 6) Hyt + F + H. Radioactive loss determined the percentage attachment and then percentage retention of labeled inoculum after a one-hour in vitro perfusion. Scanning electron and light microscopy demonstrated the endothelium on the graft surface following perfusion. Fibronectin-coated grafts had a significantly higher percentage attachment than those without fibronectin (ANOVA, P less than 0.05). However, the percentage retention following perfusion was similar for all Dacron grafts and statistically inferior to the HytrelR grafts studied (ANOVA, P less than 0.05). SEM evaluation of the C + F + H graft surface was qualitatively the most impressive Dacron surface for seeding, yet was inferior to the HytrelR graft. We conclude that fibronectin benefits the initial attachment of endothelium to collagen-coated Dacron rivaling the HytrelR surface. Fibronectin does not improve percentage retention of the HemashieldR surface during perfusion, therefore, some of its initial benefit is lost.
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