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Northern General Hospital

Hospital / health systemSheffield, United Kingdom

Research output, citation impact, and the most-cited recent papers from Northern General Hospital (United Kingdom). Aggregated across the NobleBlocks index of 300M+ scholarly works.

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7.8K
Citations
670.2K
h-index
297
i10-index
9.0K
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Northern General Hospital

Top-cited papers from Northern General Hospital

KDIGO Clinical Practice Guidelines for Acute Kidney Injury
Arif Khwaja
2012· Nephron Clinical Practice7.9Kdoi:10.1159/000339789

tion’, implying that most patients ‘should’ receive a particular action. In contrast, level 2 guidelines are essentially ‘suggestions’ and are deemed to be ‘weak’ or discretionary, recognising that management decisions may vary in different clinical contexts. Each recommendation was further graded from A to D by the quality of evidence underpinning them, with grade A referring to a high quality of evidence whilst grade D recognised a ‘very low’ evidence base. The overall strength and quality of the supporting evidence is summarised in table 1 . The guidelines focused on 4 key domains: (1) AKI definition, (2) prevention and treatment of AKI, (3) contrastinduced AKI (CI-AKI) and (4) dialysis interventions for the treatment of AKI. The full summary of clinical practice statements is available at www.kdigo.org, but a few key recommendation statements will be highlighted here.

Sample size of 12 per group rule of thumb for a pilot study
Steven A. Julious
2005· Pharmaceutical Statistics3.0Kdoi:10.1002/pst.185

Abstract When designing a clinical trial an appropriate justification for the sample size should be provided in the protocol. However, there are a number of settings when undertaking a pilot trial when there is no prior information to base a sample size on. For such pilot studies the recommendation is a sample size of 12 per group. The justifications for this sample size are based on rationale about feasibility; precision about the mean and variance; and regulatory considerations. The context of the justifications are that future studies will use the information from the pilot in their design. Copyright © 2005 John Wiley & Sons, Ltd.

Osteoporosis in the European Union: medical management, epidemiology and economic burden
E Hernlund, A Svedbom, M Ivergård, J. Compston +4 more
2013· Archives of Osteoporosis2.6Kdoi:10.1007/s11657-013-0136-1

UNLABELLED: This report describes the epidemiology, burden, and treatment of osteoporosis in the 27 countries of the European Union (EU27). INTRODUCTION: Osteoporosis is characterized by reduced bone mass and disruption of bone architecture, resulting in increased risk of fragility fractures which represent the main clinical consequence of the disease. Fragility fractures are associated with substantial pain and suffering, disability and even death for affected patients and substantial costs to society. The aim of this report was to characterize the burden of osteoporosis in the EU27 in 2010 and beyond. METHODS: The literature on fracture incidence and costs of fractures in the EU27 was reviewed and incorporated into a model estimating the clinical and economic burden of osteoporotic fractures in 2010. RESULTS: Twenty-two million women and 5.5 million men were estimated to have osteoporosis; and 3.5 million new fragility fractures were sustained, comprising 610,000 hip fractures, 520,000 vertebral fractures, 560,000 forearm fractures and 1,800,000 other fractures (i.e. fractures of the pelvis, rib, humerus, tibia, fibula, clavicle, scapula, sternum and other femoral fractures). The economic burden of incident and prior fragility fractures was estimated at <euro> 37 billion. Incident fractures represented 66 % of this cost, long-term fracture care 29 % and pharmacological prevention 5 %. Previous and incident fractures also accounted for 1,180,000 quality-adjusted life years lost during 2010. The costs are expected to increase by 25 % in 2025. The majority of individuals who have sustained an osteoporosis-related fracture or who are at high risk of fracture are untreated and the number of patients on treatment is declining. CONCLUSIONS: In spite of the high social and economic cost of osteoporosis, a substantial treatment gap and projected increase of the economic burden driven by the aging populations, the use of pharmacological interventions to prevent fractures has decreased in recent years, suggesting that a change in healthcare policy is warranted.

FRAX™ and the assessment of fracture probability in men and women from the UK
John А. Kanis, Olof Johnell, A. Oden, Håkan Johansson +1 more
2008· Osteoporosis International2.4Kdoi:10.1007/s00198-007-0543-5

UNLABELLED: A fracture risk assessment tool (FRAX) is developed based on the use of clinical risk factors with or without bone mineral density tests applied to the UK. INTRODUCTION: The aim of this study was to apply an assessment tool for the prediction of fracture in men and women with the use of clinical risk factors (CRFs) for fracture with and without the use of femoral neck bone mineral density (BMD). The clinical risk factors, identified from previous meta-analyses, comprised body mass index (BMI, as a continuous variable), a prior history of fracture, a parental history of hip fracture, use of oral glucocorticoids, rheumatoid arthritis and other secondary causes of osteoporosis, current smoking, and alcohol intake 3 or more units daily. METHODS: Four models were constructed to compute fracture probabilities based on the epidemiology of fracture in the UK. The models comprised the ten-year probability of hip fracture, with and without femoral neck BMD, and the ten-year probability of a major osteoporotic fracture, with and without BMD. For each model fracture and death hazards were computed as continuous functions. RESULTS: Each clinical risk factor contributed to fracture probability. In the absence of BMD, hip fracture probability in women with a fixed BMI (25 kg/m(2)) ranged from 0.2% at the age of 50 years for women without CRF's to 22% at the age of 80 years with a parental history of hip fracture (approximately 100-fold range). In men, the probabilities were lower, as was the range (0.1 to 11% in the examples above). For a major osteoporotic fracture the probabilities ranged from 3.5% to 31% in women, and from 2.8% to 15% in men in the example above. The presence of one or more risk factors increased probabilities in an incremental manner. The differences in probabilities between men and women were comparable at any given T-score and age, except in the elderly where probabilities were higher in women than in men due to the higher mortality of the latter. CONCLUSION: The models provide a framework which enhances the assessment of fracture risk in both men and women by the integration of clinical risk factors alone and/or in combination with BMD.

Diagnosis and Complications of Cushing’s Syndrome: A Consensus Statement
Giorgio Arnaldi, Alberto Angeli, A. B. Atkinson, Xavier Bertagna +4 more
2003· The Journal of Clinical Endocrinology & Metabolism1.4Kdoi:10.1210/jc.2003-030871

In October 2002, a workshop was held in Ancona, Italy, to reach a Consensus on the management of Cushing's syndrome. The workshop was organized by the University of Ancona and sponsored by the Pituitary Society, the European Neuroendocrine Association, and the Italian Society of Endocrinology. Invited international participants included almost 50 leading endocrinologists with specific expertise in the management of Cushing's syndrome. The consensus statement on diagnostic criteria and the diagnosis and treatment of complications of this syndrome reached at the workshop is hereby summarized.

Mapping the human genetic architecture of COVID-19
COVID-19 Host Genetics Initiative, COVID-19 Host Genetics InitiativeLeadership, Mari Niemi, Juha Karjalainen +4 more
2021· Nature1.1Kdoi:10.1038/s41586-021-03767-x

Abstract The genetic make-up of an individual contributes to the susceptibility and response to viral infection. Although environmental, clinical and social factors have a role in the chance of exposure to SARS-CoV-2 and the severity of COVID-19 1,2 , host genetics may also be important. Identifying host-specific genetic factors may reveal biological mechanisms of therapeutic relevance and clarify causal relationships of modifiable environmental risk factors for SARS-CoV-2 infection and outcomes. We formed a global network of researchers to investigate the role of human genetics in SARS-CoV-2 infection and COVID-19 severity. Here we describe the results of three genome-wide association meta-analyses that consist of up to 49,562 patients with COVID-19 from 46 studies across 19 countries. We report 13 genome-wide significant loci that are associated with SARS-CoV-2 infection or severe manifestations of COVID-19. Several of these loci correspond to previously documented associations to lung or autoimmune and inflammatory diseases 3–7 . They also represent potentially actionable mechanisms in response to infection. Mendelian randomization analyses support a causal role for smoking and body-mass index for severe COVID-19 although not for type II diabetes. The identification of novel host genetic factors associated with COVID-19 was made possible by the community of human genetics researchers coming together to prioritize the sharing of data, results, resources and analytical frameworks. This working model of international collaboration underscores what is possible for future genetic discoveries in emerging pandemics, or indeed for any complex human disease.

Ultrasonic locating devices for central venous cannulation: meta-analysis
Daniel Hind, Neill Calvert, Richard McWilliams, Andrew Davidson +3 more
2003· BMJ1.1Kdoi:10.1136/bmj.327.7411.361

OBJECTIVES: To assess the evidence for the clinical effectiveness of ultrasound guided central venous cannulation. DATA SOURCES: 15 electronic bibliographic databases, covering biomedical, science, social science, health economics, and grey literature. DESIGN: Systematic review and meta-analysis of randomised controlled trials. Populations Patients scheduled for central venous access. INTERVENTION REVIEWED: Guidance using real time two dimensional ultrasonography or Doppler needles and probes compared with the anatomical landmark method of cannulation. DATA EXTRACTION: Risk of failed catheter placement (primary outcome), risk of complications from placement, risk of failure on first attempt at placement, number of attempts to successful catheterisation, and time (seconds) to successful catheterisation. DATA SYNTHESIS: 18 trials (1646 participants) were identified. Compared with the landmark method, real time two dimensional ultrasound guidance for cannulating the internal jugular vein in adults was associated with a significantly lower failure rate both overall (relative risk 0.14, 95% confidence interval 0.06 to 0.33) and on the first attempt (0.59, 0.39 to 0.88). Limited evidence favoured two dimensional ultrasound guidance for subclavian vein and femoral vein procedures in adults (0.14, 0.04 to 0.57 and 0.29, 0.07 to 1.21, respectively). Three studies in infants confirmed a higher success rate with two dimensional ultrasonography for internal jugular procedures (0.15, 0.03 to 0.64). Doppler guided cannulation of the internal jugular vein in adults was more successful than the landmark method (0.39, 0.17 to 0.92), but the landmark method was more successful for subclavian vein procedures (1.48, 1.03 to 2.14). No significant difference was found between these techniques for cannulation of the internal jugular vein in infants. An indirect comparison of relative risks suggested that two dimensional ultrasonography would be more successful than Doppler guidance for subclavian vein procedures in adults (0.09, 0.02 to 0.38). CONCLUSIONS: Evidence supports the use of two dimensional ultrasonography for central venous cannulation.

Graves' Disease
Anthony P. Weetman
2000· New England Journal of Medicine830doi:10.1056/nejm200010263431707

Robert Graves first identified the association of goiter, palpitations, and exophthalmos in 1835, although Caleb Parry had published details of a case 10 years earlier. The discovery of a thyroid-stimulating factor that was not thyrotropin in the serum of patients with Graves' hyperthyroidism1 was followed by the identification of this stimulator as an IgG antibody.2 It is now clear that Graves' hyperthyroidism is caused by these thyroid-stimulating antibodies, which bind to and activate the thyrotropin receptor on thyroid cells.3 Graves' disease also affects the eyes (Graves' ophthalmopathy) and the skin (localized dermopathy or myxedema), but the causes of these less . . .

Trabecular Bone Score: A Noninvasive Analytical Method Based Upon the DXA Image
Barbara C. Silva, William D. Leslie, Heinrich Resch, Olivier Lamy +4 more
2014· Journal of Bone and Mineral Research825doi:10.1002/jbmr.2176

The trabecular bone score (TBS) is a gray-level textural metric that can be extracted from the two-dimensional lumbar spine dual-energy X-ray absorptiometry (DXA) image. TBS is related to bone microarchitecture and provides skeletal information that is not captured from the standard bone mineral density (BMD) measurement. Based on experimental variograms of the projected DXA image, TBS has the potential to discern differences between DXA scans that show similar BMD measurements. An elevated TBS value correlates with better skeletal microstructure; a low TBS value correlates with weaker skeletal microstructure. Lumbar spine TBS has been evaluated in cross-sectional and longitudinal studies. The following conclusions are based upon publications reviewed in this article: 1) TBS gives lower values in postmenopausal women and in men with previous fragility fractures than their nonfractured counterparts; 2) TBS is complementary to data available by lumbar spine DXA measurements; 3) TBS results are lower in women who have sustained a fragility fracture but in whom DXA does not indicate osteoporosis or even osteopenia; 4) TBS predicts fracture risk as well as lumbar spine BMD measurements in postmenopausal women; 5) efficacious therapies for osteoporosis differ in the extent to which they influence the TBS; 6) TBS is associated with fracture risk in individuals with conditions related to reduced bone mass or bone quality. Based on these data, lumbar spine TBS holds promise as an emerging technology that could well become a valuable clinical tool in the diagnosis of osteoporosis and in fracture risk assessment.

Effective supervision in clinical practice settings: a literature review
Sue Kilminster, Brian Jolly
2000· Medical Education797doi:10.1046/j.1365-2923.2000.00758.x

CONTEXT: Clinical supervision has a vital role in postgraduate and, to some extent, undergraduate medical education. However it is probably the least investigated, discussed and developed aspect of clinical education. This large-scale, interdisciplinary review of literature addressing supervision is the first from a medical education perspective. PURPOSE: To review the literature on effective supervision in practice settings in order to identify what is known about effective supervision. CONTENT: The empirical basis of the literature is discussed and the literature reviewed to identify understandings and definitions of supervision and its purpose; theoretical models of supervision; availability, structure and content of supervision; effective supervision; skills and qualities of effective supervisors; and supervisor training and its effectiveness. CONCLUSIONS: The evidence only partially answers our original questions and suggests others. The supervision relationship is probably the single most important factor for the effectiveness of supervision, more important than the supervisory methods used. Feedback is essential and must be clear. It is important that the trainee has some control over and input into the supervisory process. Finding sufficient time for supervision can be a problem. Trainee behaviours and attitudes towards supervision require more investigation; some behaviours are detrimental both to patient care and learning. Current supervisory practice in medicine has very little empirical or theoretical basis. This review demonstrates the need for more structured and methodologically sound programmes of research into supervision in practice settings so that detailed models of effective supervision can be developed and thereby inform practice.

The role of psychological and biological factors in postinfective gut dysfunction
K-A Gwee, Y-L Leong, Christopher D. Graham, M W McKendrick +4 more
1999· Gut771doi:10.1136/gut.44.3.400

BACKGROUND: Both psychological and physiological disturbances have been implicated in the aetiopathogenesis of irritable bowel syndrome (IBS). AIMS: To investigate how the psychological factors act, and the involvement of infective and physiological factors. METHODS: Consecutive patients hospitalised for gastroenteritis reported life events for the previous 12 months, and past illness experiences on standardised questionnaires. They also completed psychometric questionnaires for anxiety, neuroticism, somatisation, and hypochondriasis. In some patients, rectal biopsy specimens were obtained during the acute illness and at three months postinfection. RESULTS: Ninety four patients completed all questionnaires: 22 patients were diagnosed with IBS after their gastroenteritis (IBS+), and 72 patients returned to normal bowel habits (IBS-). IBS+ patients reported more life events and had higher hypochondriasis scores than IBS- patients. The predictive value of the life event and hypochondriasis measures was highly significant and independent of anxiety, neuroticism, and somatisation scores, which were also elevated in IBS+ patients. Rectal biopsy specimens from 29 patients showed a chronic inflammatory response in both IBS+ and IBS- patients. Three months later, specimens from IBS+ patients continued to show increased chronic inflammatory cell counts but those from IBS- patients had returned to normal levels. IBS+ and IBS- patients exhibited rectal hypersensitivity and hyper-reactivity and rapid colonic transit compared with normal controls, but there were no significant differences between IBS+ and IBS- patients for these physiological measurements. CONCLUSION: Psychological factors most clearly predict the development of IBS symptoms after gastroenteritis but biological mechanisms also contribute towards the expression of symptoms.

EAACI Guidelines on Allergen Immunotherapy: Allergic rhinoconjunctivitis
Graham Roberts, Oliver Pfaar, Cezmi A. Akdiş, Ignacio J. Ansotegui +4 more
2017· Allergy766doi:10.1111/all.13317

Allergic rhinoconjunctivitis (AR) is an allergic disorder of the nose and eyes affecting about a fifth of the general population. Symptoms of AR can be controlled with allergen avoidance measures and pharmacotherapy. However, many patients continue to have ongoing symptoms and an impaired quality of life; pharmacotherapy may also induce some side-effects. Allergen immunotherapy (AIT) represents the only currently available treatment that targets the underlying pathophysiology, and it may have a disease-modifying effect. Either the subcutaneous (SCIT) or sublingual (SLIT) routes may be used. This Guideline has been prepared by the European Academy of Allergy and Clinical Immunology's (EAACI) Taskforce on AIT for AR and is part of the EAACI presidential project "EAACI Guidelines on Allergen Immunotherapy." It aims to provide evidence-based clinical recommendations and has been informed by a formal systematic review and meta-analysis. Its generation has followed the Appraisal of Guidelines for Research and Evaluation (AGREE II) approach. The process included involvement of the full range of stakeholders. In general, broad evidence for the clinical efficacy of AIT for AR exists but a product-specific evaluation of evidence is recommended. In general, SCIT and SLIT are recommended for both seasonal and perennial AR for its short-term benefit. The strongest evidence for long-term benefit is documented for grass AIT (especially for the grass tablets) where long-term benefit is seen. To achieve long-term efficacy, it is recommended that a minimum of 3 years of therapy is used. Many gaps in the evidence base exist, particularly around long-term benefit and use in children.

Relative contributions of testosterone and estrogen in regulating bone resorption and formation in normal elderly men
Alireza Falahati-Nini, B. Lawrence Riggs, Elizabeth J. Atkinson, W. Michael O’Fallon +2 more
2000· Journal of Clinical Investigation758doi:10.1172/jci10942

Young adult males who cannot produce or respond to estrogen (E) are osteopenic, suggesting that E may regulate bone turnover in men, as well as in women. Both bioavailable E and testosterone (T) decrease substantially in aging men, but it is unclear which deficiency is the more important factor contributing to the increased bone resorption and impaired bone formation that leads to their bone loss. Thus, we addressed this issue directly by eliminating endogenous T and E production in 59 elderly men (mean age 68 years), studying them first under conditions of physiologic T and E replacement and then assessing the impact on bone turnover of withdrawing both T and E, withdrawing only T, or only E, or continuing both. Bone resorption markers increased significantly in the absence of both hormones and were unchanged in men receiving both hormones. By two-factor ANOVA, E played the major role in preventing the increase in the bone resorption markers, whereas T had no significant effect. By contrast, serum osteocalcin, a bone formation marker, decreased in the absence of both hormones, and both E and T maintained osteocalcin levels. We conclude that in aging men, E is the dominant sex steroid regulating bone resorption, whereas both E and T are important in maintaining bone formation.

Beyond ‘person‐centred’ care: a new vision for gerontological nursing
Mike Nolan, Sue Davies, Jayne Brown, John Keady +1 more
2004· Journal of Clinical Nursing718doi:10.1111/j.1365-2702.2004.00926.x

Currently considerable emphasis is placed on the promotion of person-centred care, which has become a watchword for good practice. This paper takes a constructively critical look at some of the assumptions underpinning person-centredness, and suggests that a relationship-centred approach to care might be more appropriate. A framework describing the potential dimensions of relationship-centred care is provided, and implications for further development are considered.

Extra-pleural pneumonectomy versus no extra-pleural pneumonectomy for patients with malignant pleural mesothelioma: clinical outcomes of the Mesothelioma and Radical Surgery (MARS) randomised feasibility study
Tom Treasure, Loı̈c Lang-Lazdunski, David Waller, Judith M. Bliss +4 more
2011· The Lancet Oncology710doi:10.1016/s1470-2045(11)70149-8

BACKGROUND: The effects of extra-pleural pneumonectomy (EPP) on survival and quality of life in patients with malignant pleural mesothelioma have, to our knowledge, not been assessed in a randomised trial. We aimed to assess the clinical outcomes of patients who were randomly assigned to EPP or no EPP in the context of trimodal therapy in the Mesothelioma and Radical Surgery (MARS) feasibility study. METHODS: MARS was a multicentre randomised controlled trial in 12 UK hospitals. Patients aged 18 years or older who had pathologically confirmed mesothelioma and were deemed fit enough to undergo trimodal therapy were included. In a prerandomisation registration phase, all patients underwent induction platinum-based chemotherapy followed by clinical review. After further consent, patients were randomly assigned (1:1) to EPP followed by postoperative hemithorax irradiation or to no EPP. Randomisation was done centrally with computer-generated permuted blocks stratified by surgical centre. The main endpoints were feasibility of randomly assigning 50 patients in 1 year (results detailed in another report), proportion randomised who received treatment, proportion eligible (registered) who proceeded to randomisation, perioperative mortality, and quality of life. Patients and investigators were not masked to treatment allocation. This is the principal report of the MARS study; all patients have been recruited. Analyses were by intention to treat. This trial is registered, number ISRCTN95583524. FINDINGS: Between Oct 1, 2005, and Nov 3, 2008, 112 patients were registered and 50 were subsequently randomly assigned: 24 to EPP and 26 to no EPP. The main reasons for not proceeding to randomisation were disease progression (33 patients), inoperability (five patients), and patient choice (19 patients). EPP was completed satisfactorily in 16 of 24 patients assigned to EPP; in five patients EPP was not started and in three patients it was abandoned. Two patients in the EPP group died within 30 days and a further patient died without leaving hospital. One patient in the no EPP group died perioperatively after receiving EPP off trial in a non-MARS centre. The hazard ratio [HR] for overall survival between the EPP and no EPP groups was 1·90 (95% CI 0·92-3·93; exact p=0·082), and after adjustment for sex, histological subtype, stage, and age at randomisation the HR was 2·75 (1·21-6·26; p=0·016). Median survival was 14·4 months (5·3-18·7) for the EPP group and 19·5 months (13·4 to time not yet reached) for the no EPP group. Of the 49 randomly assigned patients who consented to quality of life assessment (EPP n=23; no EPP n=26), 12 patients in the EPP group and 19 in the no EPP group completed the quality of life questionnaires. Although median quality of life scores were lower in the EPP group than the no EPP group, no significant differences between groups were reported in the quality of life analyses. There were ten serious adverse events reported in the EPP group and two in the no EPP group. INTERPRETATION: In view of the high morbidity associated with EPP in this trial and in other non-randomised studies a larger study is not feasible. These data, although limited, suggest that radical surgery in the form of EPP within trimodal therapy offers no benefit and possibly harms patients. FUNDING: Cancer Research UK (CRUK/04/003), the June Hancock Mesothelioma Research Fund, and Guy's and St Thomas' NHS Foundation Trust.

Consensus on Microembolus Detection by TCD
E. Bernd Ringelstein, Dirk W. Droste, Viken L. Babikian, David H. Evans +4 more
1998· Stroke634doi:10.1161/01.str.29.3.725

Transcranial Doppler ultrasound is capable of detecting microembolic material, both gaseous and solid, within the intracranial cerebral arteries. To avoid discrediting this promising and exciting new technique, experts in this field met in January 1997 in Frankfurt, Germany, to discuss the limitations and problems of embolus detection and to determine guidelines for its proper use in clinical practice, as well as in scientific investigations. In particular, the authors suggest that studies report the following parameters: (1) ultrasound device, (2) transducer type and size, (3) insonated artery, (4) insonation depth, (5) algorithms for signal intensity measurement, (6) scale settings, (7) detection threshold, (8) axial extension of sample volume, (9) fast Fourier transform (FFT) size (number of points used), (10) FFT length (time), (11) FFT overlap, (12) transmitted ultrasound frequency, (13) high-pass filter settings, and (14) recording time. There was agreement that no current system of automatic embolus detection has the required sensitivity and specificity for clinical use.

Milk intake and bone mineral acquisition in adolescent girls: randomised, controlled intervention trial
Joanna Cadogan, Richard Eastell, Nicola Jones, Margo E. Barker
1997· BMJ623doi:10.1136/bmj.315.7118.1255

Abstract Objectives: To investigate the effect of milk supplementation on total body bone mineral acquisition in adolescent girls. Design: 18 month, open randomised intervention trial. Subjects: 82 white girls aged 12.2 (SD 0.3) years, recruited from four secondary schools in Sheffield. Intervention: 568 ml (one pint) of whole or reduced fat milk per day for 18 months. Main outcome measures: Total body bone mineral content and bone mineral density measured by dual energy x ray absorptiometry. Outcome measures to evaluate mechanism included biochemical markers of bone turnover (osteocalcin, bone alkaline phosphatase, deoxypyridinoline, N -telopeptide of type I collagen), and hormones important to skeletal growth (parathyroid hormone, oestradiol, insulin-like growth factor I). Results: 80 subjects completed the trial. Daily milk intake at baseline averaged 150 ml in both groups. The intervention group consumed, on average, an additional 300 ml a day throughout the trial. Compared with the control group, the intervention group had greater increases of bone mineral density (9.6% v 8.5 %, P=0.017; repeated measures analysis of variance) and bone mineral content (27.0% v 24.1 %, P=0.009). No significant differences in increments in height, weight, lean body mass, and fat mass were observed between the groups. Bone turnover was not affected by milk supplementation. Serum concentrations of insulin-like growth factor I increased in the milk group compared with the control group (35% v 25 %, P=0.02). Conclusion: Increased milk consumption significantly enhances bone mineral acquisition in adolescent girls and could favourably modify attainment of peak bone mass. Key messages Osteoporosis is a major public health problem; 40% of women will sustain an osteoporotic fracture Maximising peak bone mass at skeletal maturity may be one of the most important protective measures against fracture in later life Adolescence is a critical time for bone mineral acquisition An increase in milk consumption among adolescent girls resulted in significant gains in bone mineral over an 18 month period This simple intervention indicates that increased milk consumption may be associated with higher peak bone mass

Autoimmune Thyroid Disease: Further Developments in Our Understanding*
Anthony P. Weetman, A.M. McGregor
1994· Endocrine Reviews617doi:10.1210/edrv-15-6-788

The revolution in molecular techniques has allowed dissection of the autoimmune response in a way impossible to imagine 10 yr ago. There have been spectacular advances in our understanding of self-tolerance mechanisms and how these may fail, combined with a detailed comprehension of antigen presentation, functional T cell subsets, and TCR utilization in autoimmunity, albeit usually in animal models that resemble, but do not exactly duplicate, human diseases. More gradually, these findings are being translated to thyroid autoimmunity, where the major achievement of the last decade has been the molecular characterization of the three main thyroid autoantigens. This in turn has allowed epitope identification, although again the only clear data so far have come from animal models of EAT. Another advance has been the recognition that the thyrocyte is not a helpless target of autoaggression, being capable of expressing a wide array of immunologically active molecules, which may exacerbate or diminish the autoimmune response. In 1983, there was considerable excitement at the discovery of the first of these phenomena, namely MHC class II expression, but its possible role in autoantigen presentation remains to be defined. By analogy with pancreatic beta-cells, and based on our own data, we believe that class II-expressing thyrocytes have little, if any, such role and suspect that instead this may be a mechanism for inducing peripheral tolerance. Defining the contribution of thyrocytes to the intrathyroidal autoimmune response, whether from released cytokines or surface-bound molecules, will be crucial to our future understanding, as well as holding the promise that these thyroid-derived products might be therapeutic targets. Despite molecular developments in HLA analysis, there have been no really major improvements in our understanding of the immunogenetics of thyroid autoimmunity, equivalent to those made in type 1 diabetes mellitus. The available data suggest strongly that non-MHC genes play an important role in susceptibility, and novel approaches will be required to identify these. On the other hand, we know more about the importance of environmental and endogenous (most probably hormonal) factors in thyroid autoimmunity. Understanding the basic immunological changes in the postpartum period is still poor, however, as most studies to date have concentrated on epidemiology and clinical delineation. As PPTD undergoes spontaneous remission, elucidation of these mechanisms has clear implications for treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Sample sizes for clinical trials with Normal data
Steven A. Julious
2004· Statistics in Medicine606doi:10.1002/sim.1783

This article gives an overview of sample size calculations for parallel group and cross-over studies with Normal data. Sample size derivation is given for trials where the objective is to demonstrate: superiority, equivalence, non-inferiority, bioequivalence and estimation to a given precision, for different types I and II errors. It is demonstrated how the different trial objectives influence the null and alternative hypotheses of the trials and how these hypotheses influence the calculations. Sample size tables for the different types of trials and worked examples are given.

New ischaemic brain lesions on MRI after stenting or endarterectomy for symptomatic carotid stenosis: a substudy of the International Carotid Stenting Study (ICSS)
Leo H. Bonati, Lisa M. Jongen, Sven Haller, H. Zwenneke Flach +4 more
2010· The Lancet Neurology576doi:10.1016/s1474-4422(10)70057-0

BACKGROUND: The International Carotid Stenting Study (ICSS) of stenting and endarterectomy for symptomatic carotid stenosis found a higher incidence of stroke within 30 days of stenting compared with endarterectomy. We aimed to compare the rate of ischaemic brain injury detectable on MRI between the two groups. METHODS: Patients with recently symptomatic carotid artery stenosis enrolled in ICSS were randomly assigned in a 1:1 ratio to receive carotid artery stenting or endarterectomy. Of 50 centres in ICSS, seven took part in the MRI substudy. The protocol specified that MRI was done 1-7 days before treatment, 1-3 days after treatment (post-treatment scan), and 27-33 days after treatment. Scans were analysed by two or three investigators who were masked to treatment. The primary endpoint was the presence of at least one new ischaemic brain lesion on diffusion-weighted imaging (DWI) on the post-treatment scan. Analysis was per protocol. This is a substudy of a registered trial, ISRCTN 25337470. FINDINGS: 231 patients (124 in the stenting group and 107 in the endarterectomy group) had MRI before and after treatment. 62 (50%) of 124 patients in the stenting group and 18 (17%) of 107 patients in the endarterectomy group had at least one new DWI lesion detected on post-treatment scans done a median of 1 day after treatment (adjusted odds ratio [OR] 5.21, 95% CI 2.78-9.79; p<0.0001). At 1 month, there were changes on fluid-attenuated inversion recovery sequences in 28 (33%) of 86 patients in the stenting group and six (8%) of 75 in the endarterectomy group (adjusted OR 5.93, 95% CI 2.25-15.62; p=0.0003). In patients treated at a centre with a policy of using cerebral protection devices, 37 (73%) of 51 in the stenting group and eight (17%) of 46 in the endarterectomy group had at least one new DWI lesion on post-treatment scans (adjusted OR 12.20, 95% CI 4.53-32.84), whereas in those treated at a centre with a policy of unprotected stenting, 25 (34%) of 73 patients in the stenting group and ten (16%) of 61 in the endarterectomy group had new lesions on DWI (adjusted OR 2.70, 1.16-6.24; interaction p=0.019). INTERPRETATION: About three times more patients in the stenting group than in the endarterectomy group had new ischaemic lesions on DWI on post-treatment scans. The difference in clinical stroke risk in ICSS is therefore unlikely to have been caused by ascertainment bias. Protection devices did not seem to be effective in preventing cerebral ischaemia during stenting. DWI might serve as a surrogate outcome measure in future trials of carotid interventions. FUNDING: UK Medical Research Council, the Stroke Association, Sanofi-Synthélabo, European Union, Netherlands Heart Foundation, and Mach-Gaensslen Foundation.