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The Nuffield Department of Surgical Sciences is the academic department of surgery at the University of Oxford, and hosts a multidisciplinary team of senior clinical academic surgeons, senior scientists, junior clinicians and scientists in training.
What should doctors say to men asking for a PSA test?
© Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to. Patients need individual discussions about the benefits and harms of testing.
Researchers’ attitudes towards the use of social networking sites
© 2018, © Emerald Publishing Limited. Purpose: The purpose of this paper is to better understand why many researchers do not have a profile on social networking sites (SNS), and whether this is the result of conscious decisions. Design/methodology/approach: Thematic analysis was conducted on a large qualitative data set from researchers across three levels of seniority, four countries and four disciplines to explore their attitudes toward and experiences with SNS. Findings: The study found much greater scepticism toward adopting SNS than previously reported. Reasons behind researchers’ scepticism range from SNS being unimportant for their work to not belonging to their culture or habits. Some even felt that a profile presented people negatively and might harm their career. These concerns were mostly expressed by junior and midlevel researchers, showing that the largest opponents to SNS may unexpectedly be younger researchers. Research limitations/implications: A limitation of this study was that the authors did not conduct the interviews, and therefore reframing or adding questions to specifically unpack comments related to attitudes, feelings or the use of SNS in academia was not possible. Originality/value: By studying implicit attitudes and experiences, this study shows that instead of being ignorant of SNS profiles, some researchers actively opt for a non-use of profiles on SNS.
Keeping up to date: An academic researcher's information journey
© 2015 The Authors. Journal of the Association for Information Science and Technology published by Wiley Periodicals, Inc. on behalf of ASIS & T. Keeping up to date with research developments is a central activity of academic researchers, but researchers face difficulties in managing the rapid growth of available scientific information. This study examined how researchers stay up to date, using the information journey model as a framework for analysis and investigating which dimensions influence information behaviors. We designed a 2-round study involving semistructured interviews and prototype testing with 61 researchers with 3 levels of seniority (PhD student to professor). Data were analyzed following a semistructured qualitative approach. Five key dimensions that influence information behaviors were identified: level of seniority, information sources, state of the project, level of familiarity, and how well defined the relevant community is. These dimensions are interrelated and their values determine the flow of the information journey. Across all levels of professional expertise, researchers used similar hard (formal) sources to access content, while soft (interpersonal) sources were used to filter information. An important “pain point” that future information tools should address is helping researchers filter information at the point of need.
Molecular genetics and pathogenesis of renal cancer
© 2007 Informa UK Ltd. Renal cancer is not a single disease; it comprises several different types of cancer, each with a different histology, a different clinical course, and different genetic changes1 (Table 2.1). For each of these different tumour types, hereditary, familial, and sporadic forms exist. Most of our current knowledge was originally derived from studies on familial forms of the disease, but subsequent studies of sporadic cancers found similar changes2 (Table 2.2). Recent developments in genetics and molecular biology have led to an increasing knowledge of the origin and biology of renal cell carcinoma (RCC), which will be discussed separately for sporadic and inherited forms.
The scientific basis of urology
© 2004 by Taylor & Francis Group, LLC. Written specifically for urological trainees by a distinguished team of contributors, The Scientific Basis of Urology, Second Edition provides the reader with a thorough coverage of urology. Every area, function, illness and cure of the urinary tract, along with specific discussions of the relevant anatomy and physiology, are discussed in clearly written text, abundantly illustrated with full color photographs and diagrams. Each chapter takes the basic principles of its topic area and expands upon them to ensure maximum understanding.
Tumour suppressor genes and oncogenes
© 2004 by Taylor & Francis Group, LLC. CANCER An understanding of cancer is important to the urologist, not only because it is common, but also because its study provides insight into normal and abnormal cellular function. One in five adults die of cancer (Tables 20.1 and 20.2) and about 30-50% of common, solid epithelial tumours are advanced and incurable when first detected clinically. So far as urological tumours are concerned, prostate, bladder and kidney cancers are common, and while testis cancer is rare, it is important because, even when advanced, it is frequently curable and because it occurs in young men with an otherwise full life-expectancy.
The cell and cell division
© 2004 by Taylor & Francis Group, LLC. The cell membrane confines the contents of the cell. It consists of a continuous bilayer of phospholipid with the polar hydrophilic ends forming the outer and inner layers and the hydrophobic tails forming the central core of the bilayer. The hydrophilic heads on the two sides of the cell membrane are of different composition, those on the outside often being modified by glycosylation: a process that involves the addition of various sugar residues. Embedded in this lipid bilayer are proteins whose function can be classified as follows: Signal transduction (mediating the action of external ligands such as growth factors and neurotransmitters). These receptor proteins cross the cell membrane and may have intrinsic enzyme functions (such as the tyrosine kinase activity of the receptor for epidermal growth factor) or may be linked to other proteins such as G proteins (for example, the muscarinic acetylcholine receptor) (Figure 2.1).
Electromyographic Abnormalities in the Urethral and Anal Sphincters of Women with Idiopathic Retention of Urine
Summary— Previous concentric needle studies of the urethral sphincter in women with idiopathic urinary retention have found evidence of denervation and reinnervation as well as abnormal patterns of muscle fibre discharge—complex repetitive discharges (CRDs). In order to test the hypothesis that these abnormalities represented a more widespread disease process of pelvic floor function, we carried out an electromyographic (EMG) study of both anal and urethral sphincters in 18 women with idiopathic urinary retention. The urethral sphincter EMG was abnormal in 15 patients. These abnormalities included polyphasic and long duration potentials. Complex repetitive discharges were identified in 8 women. However, abnormalities of the anal sphincter were found in 14 of the 15 patients with abnormal urethral sphincter EMGs, polyphasic and abnormally long duration potentials being found in the anal sphincters of all 14 patients. In addition, 7 of the 8 women who had complex repetitive discharges in the urethral sphincters had similar complex repetitive discharges in their anal sphincters. Women with complex repetitive discharges had a significantly greater proportion of abnormal potentials than women with no such repetitive discharges. These results support the previous findings of electromyographic urethral sphincter abnormalities in women with idiopathic urinary retention, but also suggest that these abnormalities reflect a widespread disease process involving the pelvic floor in such patients. © 1992 British Journal of Urology
Non-Linear Dynamical Analysis of Resting Tremor for Demand-Driven Deep Brain Stimulation.
Parkinson's Disease (PD) is currently the second most common neurodegenerative disease. One of the most characteristic symptoms of PD is resting tremor. Local Field Potentials (LFPs) have been widely studied to investigate deviations from the typical patterns of healthy brain activity. However, the inherent dynamics of the Sub-Thalamic Nucleus (STN) LFPs and their spatiotemporal dynamics have not been well characterized. In this work, we study the non-linear dynamical behaviour of STN-LFPs of Parkinsonian patients using ε -recurrence networks. RNs are a non-linear analysis tool that encodes the geometric information of the underlying system, which can be characterised (for example, using graph theoretical measures) to extract information on the geometric properties of the attractor. Results show that the activity of the STN becomes more non-linear during the tremor episodes and that ε -recurrence network analysis is a suitable method to distinguish the transitions between movement conditions, anticipating the onset of the tremor, with the potential for application in a demand-driven deep brain stimulation system.
Restenosis and risk of stroke after stenting or endarterectomy for symptomatic carotid stenosis in the International Carotid Stenting Study (ICSS): secondary analysis of a randomised trial.
BACKGROUND: The risk of stroke associated with carotid artery restenosis after stenting or endarterectomy is unclear. We aimed to compare the long-term risk of restenosis after these treatments and to investigate if restenosis causes stroke in a secondary analysis of the International Carotid Stenting Study (ICSS). METHODS: ICSS is a parallel-group randomised trial at 50 tertiary care centres in Europe, Australia, New Zealand, and Canada. Patients aged 40 years or older with symptomatic carotid stenosis measuring 50% or more were randomly assigned either stenting or endarterectomy in a 1:1 ratio. Randomisation was computer-generated and done centrally, with allocation by telephone or fax, stratified by centre, and with minimisation for sex, age, side of stenosis, and occlusion of the contralateral carotid artery. Patients were followed up both clinically and with carotid duplex ultrasound at baseline, 30 days after treatment, 6 months after randomisation, then annually for up to 10 years. We included patients whose assigned treatment was completed and who had at least one ultrasound examination after treatment. Restenosis was defined as any narrowing of the treated artery measuring 50% or more (at least moderate) or 70% or more (severe), or occlusion of the artery. The degree of restenosis based on ultrasound velocities and clinical outcome events were adjudicated centrally; assessors were masked to treatment assignment. Restenosis was analysed using interval-censored models and its association with later ipsilateral stroke using Cox regression. This trial is registered with the ISRCTN registry, number ISRCTN25337470. This report presents a secondary analysis, and follow-up is complete. FINDINGS: Between May, 2001, and October, 2008, 1713 patients were enrolled and randomly allocated treatment (855 were assigned stenting and 858 endarterectomy), of whom 1530 individuals were followed up with ultrasound (737 assigned stenting and 793 endarterectomy) for a median of 4·0 years (IQR 2·3-5·0). At least moderate restenosis (≥50%) occurred in 274 patients after stenting (cumulative 5-year risk 40·7%) and in 217 after endarterectomy (29·6%; unadjusted hazard ratio [HR] 1·43, 95% CI 1·21-1·72; p<0·0001). Patients with at least moderate restenosis (≥50%) had a higher risk of ipsilateral stroke than did individuals without restenosis in the overall patient population (HR 3·18, 95% CI 1·52-6·67; p=0·002) and in the endarterectomy group alone (5·75, 1·80-18·33; p=0·003), but no significant increase in stroke risk after restenosis was recorded in the stenting group (2·03, 0·77-5·37; p=0·154; p=0·10 for interaction with treatment). No difference was noted in the risk of severe restenosis (≥70%) or subsequent stroke between the two treatment groups. INTERPRETATION: At least moderate (≥50%) restenosis occurred more frequently after stenting than after endarterectomy and increased the risk for ipsilateral stroke in the overall population. Whether the restenosis-mediated risk of stroke differs between stenting and endarterectomy requires further research. FUNDING: Medical Research Council, the Stroke Association, Sanofi-Synthélabo, and the European Union.
High Operator and Hospital Volume Are Associated With a Decreased Risk of Death and Stroke After Carotid Revascularization: A Systematic Review and Meta-analysis.
OBJECTIVE: To examine the association between operator or hospital volume and procedural outcomes of carotid revascularization. BACKGROUND: Operator and hospital volume have been proposed as determinants of outcome after carotid endarterectomy (CEA) or carotid artery stenting (CAS). The magnitude and clinical relevance of this relationship are debated. METHODS: We systematically searched PubMed and EMBASE until August 21, 2017. The primary outcome was procedural (30 days, in-hospital, or perioperative) death or stroke. Obtained or estimated risk estimates were pooled with a generic inverse variance random-effects model. RESULTS: We included 87 studies. A decreased risk of death or stroke following CEA was found for high compared to low operator volume with a pooled adjusted odds ratio (OR) of 0.50 (95% confidence interval [CI] 0.28-0.87; 3 cohorts), and a pooled unadjusted relative risk (RR) of 0.59 (95% CI 0.42-0.83; 9 cohorts); for high compared to low hospital volume with a pooled adjusted OR of 0.62 (95% CI 0.42-0.90; 5 cohorts), and a pooled unadjusted RR of 0.68 (95% CI 0.51-0.92; 9 cohorts). A decreased risk of death or stroke after CAS was found for high compared to low operator volume with an adjusted OR of 0.43 (95% CI 0.20-0.95; 1 cohort), and an unadjusted RR of 0.50 (95% CI 0.32-0.79; 1 cohort); for high compared to low hospital volume with an adjusted OR of 0.46 (95% CI 0.26-0.80; 1 cohort), and no significant decreased risk in a pooled unadjusted RR of 0.72 (95% CI 0.49-1.06; 2 cohorts). CONCLUSIONS: We found a decreased risk of procedural death and stroke after CEA and CAS for high operator and high hospital volume, indicating that aiming for a high volume may help to reduce procedural complications. REGISTRATION: This systematic review has been registered in the international prospective registry of systematic reviews (PROSPERO): CRD42017051491.
Long-term outcomes of stenting and endarterectomy for symptomatic carotid stenosis: a preplanned pooled analysis of individual patient data.
BACKGROUND: The risk of periprocedural stroke or death is higher after carotid artery stenting (CAS) than carotid endarterectomy (CEA) for the treatment of symptomatic carotid stenosis. However, long-term outcomes have not been sufficiently assessed. We sought to combine individual patient-level data from the four major randomised controlled trials of CAS versus CEA for the treatment of symptomatic carotid stenosis to assess long-term outcomes. METHODS: We did a pooled analysis of individual patient-level data, acquired from the four largest randomised controlled trials assessing the relative efficacy of CAS and CEA for treatment of symptomatic carotid stenosis (Endarterectomy versus Angioplasty in Patients with Symptomatic Severe Carotid Stenosis trial, Stent-Protected Percutaneous Angioplasty of the Carotid Artery versus Endarterectomy trial, International Carotid Stenting Study, and Carotid Revascularization Endarterectomy versus Stenting Trial). The risk of ipsilateral stroke was assessed between 121 days and 1, 3, 5, 7, 9, and 10 years after randomisation. The primary outcome was the composite risk of stroke or death within 120 days after randomisation (periprocedural risk) or subsequent ipsilateral stroke up to 10 years after randomisation (postprocedural risk). Analyses were intention-to-treat, with the risk of events calculated using Kaplan-Meier methods and Cox proportional hazards analysis with adjustment for trial. FINDINGS: In the four trials included, 4775 patients were randomly assigned, of whom a total of 4754 (99·6%) patients were followed up for a maximum of 12·4 years. 21 (0·4%) patients immediately withdrew consent after randomisation and were excluded. Median length of follow-up across the studies ranged from 2·0 to 6·9 years. 129 periprocedural and 55 postprocedural outcome events occurred in patients allocated CEA, and 206 and 57 for those allocated CAS. After the periprocedural period, the annual rates of ipsilateral stroke per person-year were similar for the two treatments: 0·60% (95% CI 0·46-0·79) for CEA and 0·64% (0·49-0·83) for CAS. Nonetheless, the periprocedural and postprocedural risks combined favoured CEA, with treatment differences at 1, 3, 5, 7, and 9 years all ranging between 2·8% (1·1-4·4) and 4·1% (2·0-6·3). INTERPRETATION: Outcomes in the postprocedural period after CAS and CEA were similar, suggesting robust clinical durability for both treatments. Although long-term outcomes (periprocedural and postprocedural risks combined) continue to favour CEA, the similarity of the postprocedural rates suggest that improvements in the periprocedural safety of CAS could provide similar outcomes of the two procedures in the future. FUNDING: None.
Three-year outcomes after carotid artery revascularization: Gender-related differences
© The Author(s) 2019. Objectives: Carotid artery stenosis is thought to cause up to 10% of ischemic strokes. Historically, carotid artery endarterectomy has shown a higher risk of perioperative adverse events for women. More recent trials reported conflicting results regarding the benefit of carotid artery endarterectomy and carotid artery stenting for men and women. The aim of the present retrospective study was to investigate the influence of gender on the short- (30 days) and long-term (3 years) outcomes of carotid artery endarterectomy and carotid artery stenting in a single centre. Methods: From 2010 to 2017, 912 consecutive symptomatic and asymptomatic patients who underwent carotid artery endarterectomy (389, 42.7%) or carotid artery stenting (523, 57.3%) in a single institution had been evaluated to determine the influence of sex (540 men, 59.2%, vs. 372 women, 40.8%) on the outcomes after both revascularization procedures during three years of follow-up. The primary endpoint was the incidence of death, stroke, myocardial infarction, and restenosis in the short-term follow-up. The secondary endpoint was the incidence of death, stroke, myocardial infarction, and restenosis in the long-term follow-up. Results: Mean clinical follow-up was 21.1 (16.1) months. Women had internal and common carotid artery diameters significantly smaller with respect to men. For peri-procedural outcomes, women undergoing carotid artery stenting had a higher risk of moderate (50–70%) restenosis (6 women, 2.9%, vs. 3 men, 1.0%). For long-term outcomes, women undergoing carotid artery endarterectomy had a higher rate of moderate restenosis (16 women, 16.3%, vs. 11 men, 7.6%). No significant differences in long-term outcomes were observed between men and women undergoing carotid artery stenting, even after stratification for baseline risk factors. Conclusions: Contrary to previous reports, from this single-centre study, long-term risk of events seems to be higher in women who underwent carotid artery endarterectomy than in those who underwent carotid artery stenting, while fewer differences were observed in men.
Awake stereotactic biopsy of brain stem lesions: technique and results.
BACKGROUND: Brain stem lesions are a heterogenous pathological group. In adults, pre-operative radiological diagnoses prove to be wrong in 10 to 20% of cases. It is therefore imperative to have a tissue diagnosis for appropriate therapeutic measures. Unless these lesions have a sizeable exophytic component, open biopsy and/or resection is marred by low diagnostic yield and prohibitive mortality/morbidity rates. METHODS: We describe our experience with awake stereotactic biopsy of brain stem lesions. Keeping the patient awake and monitoring clinically during the procedure allows us to make necessary changes in the trajectory of the biopsy probe to minimize the morbidity. A series of 13 brain stem lesions were stereotactically biopsied using CT guidance. Seven had midbrain lesions; four had pontine and two had Ponto-medullary lesions. A frontal, pre-coronal, transcortical trajectory was used in all patients. FINDINGS: Histological diagnosis was established in all but one patient. There was no procedural mortality, and morbidity was minimal and temporary, occurring in three patients. CONCLUSION: Awake stereotactic biopsy is a safe technique when combined with clinical monitoring.