scispace - formally typeset
Search or ask a question

Showing papers by "John Radcliffe Hospital published in 2010"



Journal ArticleDOI
TL;DR: Visit-to-visit variability in systolic blood pressure (SBP) and maximum SBP are strong predictors of stroke, independent of mean SBP.

1,522 citations


Journal ArticleDOI
20 Dec 2010-PLOS ONE
TL;DR: The novel M-EPI pulse sequence resulted in a significantly increased temporal resolution for whole brain fMRI, and as such, this new methodology can be used for studying non-stationarity in networks and generally for expanding and enriching the functional information.
Abstract: Echo planar imaging (EPI) is an MRI technique of particular value to neuroscience, with its use for virtually all functional MRI (fMRI) and diffusion imaging of fiber connections in the human brain. EPI generates a single 2D image in a fraction of a second; however, it requires 2–3 seconds to acquire multi-slice whole brain coverage for fMRI and even longer for diffusion imaging. Here we report on a large reduction in EPI whole brain scan time at 3 and 7 Tesla, without significantly sacrificing spatial resolution, and while gaining functional sensitivity. The multiplexed-EPI (M-EPI) pulse sequence combines two forms of multiplexing: temporal multiplexing (m) utilizing simultaneous echo refocused (SIR) EPI and spatial multiplexing (n) with multibanded RF pulses (MB) to achieve m×n images in an EPI echo train instead of the normal single image. This resulted in an unprecedented reduction in EPI scan time for whole brain fMRI performed at 3 Tesla, permitting TRs of 400 ms and 800 ms compared to a more conventional 2.5 sec TR, and 2–4 times reductions in scan time for HARDI imaging of neuronal fibertracks. The simultaneous SE refocusing of SIR imaging at 7 Tesla advantageously reduced SAR by using fewer RF refocusing pulses and by shifting fat signal out of the image plane so that fat suppression pulses were not required. In preliminary studies of resting state functional networks identified through independent component analysis, the 6-fold higher sampling rate increased the peak functional sensitivity by 60%. The novel M-EPI pulse sequence resulted in a significantly increased temporal resolution for whole brain fMRI, and as such, this new methodology can be used for studying non-stationarity in networks and generally for expanding and enriching the functional information.

1,257 citations


Journal ArticleDOI
27 Jul 2010-Brain
TL;DR: The identification of leucine-rich, glioma inactivated 1 protein and contactin-associated protein-2 as the major targets of potassium channel antibodies, and their associations with different clinical features, begins to explain the diversity of these syndromes.
Abstract: Antibodies that immunoprecipitate (125)I-alpha-dendrotoxin-labelled voltage-gated potassium channels extracted from mammalian brain tissue have been identified in patients with neuromyotonia, Morvan's syndrome, limbic encephalitis and a few cases of adult-onset epilepsy. These conditions often improve following immunomodulatory therapies. However, the proportions of the different syndromes, the numbers with associated tumours and the relationships with potassium channel subunit antibody specificities have been unclear. We documented the clinical phenotype and tumour associations in 96 potassium channel antibody positive patients (titres >400 pM). Five had thymomas and one had an endometrial adenocarcinoma. To define the antibody specificities, we looked for binding of serum antibodies and their effects on potassium channel currents using human embryonic kidney cells expressing the potassium channel subunits. Surprisingly, only three of the patients had antibodies directed against the potassium channel subunits. By contrast, we found antibodies to three proteins that are complexed with (125)I-alpha-dendrotoxin-labelled potassium channels in brain extracts: (i) contactin-associated protein-2 that is localized at the juxtaparanodes in myelinated axons; (ii) leucine-rich, glioma inactivated 1 protein that is most strongly expressed in the hippocampus; and (iii) Tag-1/contactin-2 that associates with contactin-associated protein-2. Antibodies to Kv1 subunits were found in three sera, to contactin-associated protein-2 in 19 sera, to leucine-rich, glioma inactivated 1 protein in 55 sera and to contactin-2 in five sera, four of which were also positive for the other antibodies. The remaining 18 sera were negative for potassium channel subunits and associated proteins by the methods employed. Of the 19 patients with contactin-associated protein-antibody-2, 10 had neuromyotonia or Morvan's syndrome, compared with only 3 of the 55 leucine-rich, glioma inactivated 1 protein-antibody positive patients (P < 0.0001), who predominantly had limbic encephalitis. The responses to immunomodulatory therapies, defined by changes in modified Rankin scores, were good except in the patients with tumours, who all had contactin-associated-2 protein antibodies. This study confirms that the majority of patients with high potassium channel antibodies have limbic encephalitis without tumours. The identification of leucine-rich, glioma inactivated 1 protein and contactin-associated protein-2 as the major targets of potassium channel antibodies, and their associations with different clinical features, begins to explain the diversity of these syndromes; furthermore, detection of contactin-associated protein-2 antibodies should help identify the risk of an underlying tumour and a poor prognosis in future patients.

1,115 citations


Journal ArticleDOI
TL;DR: Intended for use by physicians, these recommendations suggest preferred approaches to the diagnostic, therapeutic and preventative aspects of care that are intended to be flexible, in contrast to standards of care, which are inflexible policies to be followed in every case.

1,088 citations


Journal ArticleDOI
TL;DR: In this article, the finding of homozygous EZH2 mutations in 9 of 12 individuals with 7q acquired uniparental disomy was described, and the mutations resulted in premature chain termination or direct abrogation of histone methyltransferase activity.
Abstract: Abnormalities of chromosome 7q are common in myeloid malignancies, but no specific target genes have yet been identified. Here, we describe the finding of homozygous EZH2 mutations in 9 of 12 individuals with 7q acquired uniparental disomy. Screening of a total of 614 individuals with myeloid disorders revealed 49 monoallelic or biallelic EZH2 mutations in 42 individuals; the mutations were found most commonly in those with myelodysplastic/myeloproliferative neoplasms (27 out of 219 individuals, or 12%) and in those with myelofibrosis (4 out of 30 individuals, or 13%). EZH2 encodes the catalytic subunit of the polycomb repressive complex 2 (PRC2), a highly conserved histone H3 lysine 27 (H3K27) methyltransferase that influences stem cell renewal by epigenetic repression of genes involved in cell fate decisions. EZH2 has oncogenic activity, and its overexpression has previously been causally linked to differentiation blocks in epithelial tumors. Notably, the mutations we identified resulted in premature chain termination or direct abrogation of histone methyltransferase activity, suggesting that EZH2 acts as a tumor suppressor for myeloid malignancies.

1,061 citations


Journal ArticleDOI
TL;DR: The proportion of cases with unknown cause was higher than that for any specific identified cause, and patients who died were more likely to be immunocompromised than were those who survived (OR = 3·44).
Abstract: Summary Background Encephalitis has many causes, but for most patients the cause is unknown. We aimed to establish the cause and identify the clinical differences between causes in patients with encephalitis in England. Methods Patients of all ages and with symptoms suggestive of encephalitis were actively recruited for 2 years (staged start between October, 2005, and November, 2006) from 24 hospitals by clinical staff. Systematic laboratory testing included PCR and antibody assays for all commonly recognised causes of infectious encephalitis, investigation for less commonly recognised causes in immunocompromised patients, and testing for travel-related causes if indicated. We also tested for non-infectious causes for acute encephalitis including autoimmunity. A multidisciplinary expert team reviewed clinical presentation and hospital tests and directed further investigations. Patients were followed up for 6 months after discharge from hospital. Findings We identified 203 patients with encephalitis. Median age was 30 years (range 0–87). 86 patients (42%, 95% CI 35–49) had infectious causes, including 38 (19%, 14–25) herpes simplex virus, ten (5%, 2–9) varicella zoster virus, and ten (5%, 2–9) Mycobacterium tuberculosis ; 75 (37%, 30–44) had unknown causes. 42 patients (21%, 15–27) had acute immune-mediated encephalitis. 24 patients (12%, 8–17) died, with higher case fatality for infections from M tuberculosis (three patients; 30%, 7–65) and varicella zoster virus (two patients; 20%, 2–56). The 16 patients with antibody-associated encephalitis had the worst outcome of all groups—nine (56%, 30–80) either died or had severe disabilities. Patients who died were more likely to be immunocompromised than were those who survived (OR=3·44). Interpretation Early diagnosis of encephalitis is crucial to ensure that the right treatment is given on time. Extensive testing substantially reduced the proportion with unknown cause, but the proportion of cases with unknown cause was higher than that for any specific identified cause. Funding The Policy Research Programme, Department of Health, UK.

1,021 citations


Journal ArticleDOI
TL;DR: It is shown that NOD2-mediated autophagy is required for both bacterial handling and generation of major histocompatibility complex (MHC) class II antigen-specific CD4+ T cell responses in DCs, and defects in this pathway in Crohn's disease DCs are revealed.
Abstract: Nucleotide-binding oligomerization domain-containing-2 (NOD2) acts as a bacterial sensor in dendritic cells (DCs), but it is not clear how bacterial recognition links with antigen presentation after NOD2 stimulation. NOD2 variants are associated with Crohn's disease, where breakdown in self-recognition of commensal bacteria leads to gastrointestinal inflammation. Here we show NOD2 triggering by muramyldipeptide induces autophagy in DCs. This effect requires receptor-interacting serine-threonine kinase-2 (RIPK-2), autophagy-related protein-5 (ATG5), ATG7 and ATG16L1 but not NLR family, pyrin domain containing-3 (NALP3).We show that NOD2-mediated autophagy is required for both bacterial handling and generation of major histocompatibility complex (MHC) class II antigen-specific CD4(+) T cell responses in DCs. DCs from individuals with Crohn's disease expressing Crohn's disease-associated NOD2 or ATG16L1 risk variants are defective in autophagy induction, bacterial trafficking and antigen presentation. Our findings link two Crohn's disease-associated susceptibility genes in a single functional pathway and reveal defects in this pathway in Crohn's disease DCs that could lead to bacterial persistence via impaired lysosomal destruction and immune mediated clearance.

988 citations


Journal ArticleDOI
29 Apr 2010-Nature
TL;DR: It is shown that bacteria-driven innate colitis is associated with an increased production of IL-17 and interferon-γ in the colon, and IL-23-responsive innate intestinal cells are identified, which may represent a target in inflammatory bowel disease.
Abstract: The key role of interleukin (IL)-23 in the pathogenesis of autoimmune and chronic inflammatory disorders is supported by the identification of IL-23 receptor (IL-23R) susceptibility alleles associated with inflammatory bowel disease, psoriasis and ankylosing spondylitis. IL-23-driven inflammation has primarily been linked to the actions of T-helper type 17 (TH17) cells. Somewhat overlooked, IL-23 also has inflammatory effects on innate immune cells and can drive T-cell-independent colitis. However, the downstream cellular and molecular pathways involved in this innate intestinal inflammatory response are poorly characterized. Here we show that bacteria-driven innate colitis is associated with an increased production of IL-17 and interferon-gamma in the colon. Stimulation of colonic leukocytes with IL-23 induced the production of IL-17 and interferon-gamma exclusively by innate lymphoid cells expressing Thy1, stem cell antigen 1 (SCA-1), retinoic-acid-related orphan receptor (ROR)-gammat and IL-23R, and these cells markedly accumulated in the inflamed colon. IL-23-responsive innate intestinal cells are also a feature of T-cell-dependent models of colitis. The transcription factor ROR-gammat, which controls IL-23R expression, has a functional role, because Rag-/-Rorc-/- mice failed to develop innate colitis. Last, depletion of Thy1+ innate lymphoid cells completely abrogated acute and chronic innate colitis. These results identify a previously unrecognized IL-23-responsive innate lymphoid population that mediates intestinal immune pathology and may therefore represent a target in inflammatory bowel disease.

976 citations



Journal ArticleDOI
01 Jun 2010-Brain
TL;DR: Overall, the data support a model in which the early features of N-methyl-d-aspartate receptor encephalopathy are associated with cerebrospinal fluid lymphocytosis, and the later features with appearance of oligoclonal bands, which is associated with restriction to the first stage.
Abstract: Antibodies to the N-methyl-d-aspartate subtype of glutamate receptor have been associated with a newly-described encephalopathy that has been mainly identified in young females with ovarian tumours. However, the full clinical spectrum and treatment responses are not yet clear. We established a sensitive cell-based assay for detection of N-methyl-d-aspartate receptor antibodies in serum or cerebrospinal fluid, and a quantitative fluorescent immunoprecipitation assay for serial studies. Although there was marked intrathecal synthesis of N-methyl-d-aspartate receptor antibodies, the absolute levels of N-methyl-d-aspartate receptor antibodies were higher in serum than in cerebrospinal fluid. N-methyl-d-aspartate receptor antibodies were of the immunoglobulin G1 subclass and were able to activate complement on N-methyl d-aspartate receptor-expressing human embryonic kidney cells. From questionnaires returned on 44 N-methyl-d-aspartate receptor antibody-positive patients, we identified a high proportion without a detected tumour (35/44, 80%: follow-up 3.6–121 months, median 16 months). Among the latter were 15 adult females (43%), 10 adult males (29%) and 10 children (29%), with four in the first decade of life. Overall, there was a high proportion (29%) of non-Caucasians. Good clinical outcomes, as defined by reductions in modified Rankin scores, correlated with decreased N-methyl-d-aspartate receptor antibody levels and were associated with early (<40 days) administration of immunotherapies in non-paraneoplastic patients (P < 0.0001) and earlier tumour removal in paraneoplastic patients (P = 0.02). Ten patients (23%) who were first diagnosed during relapses had no evidence of tumours but had received minimal or no immunotherapy during earlier episodes. Temporal analysis of the onset of the neurological features suggested progression through two main stages. The time of onset of the early features, characterized by neuropsychiatric symptoms and seizures preceded by a median of 10–20 days, the onset of movement disorders, reduction in consciousness and dysautonomia. This temporal dichotomy was also seen in the timing of cerebrospinal fluid, electroencephalographic and in the rather infrequent cerebral imaging changes. Overall, our data support a model in which the early features are associated with cerebrospinal fluid lymphocytosis, and the later features with appearance of oligoclonal bands. The immunological events and neuronal mechanisms underlying these observations need to be explored further, but one possibility is that the early stage represents diffusion of serum antibodies into the cortical grey matter, whereas the later stage results from secondary expansion of the immunological repertoire within the intrathecal compartment acting on subcortical neurons. Four patients, who only had temporal lobe epilepsy without oligoclonal bands, may represent restriction to the first stage.

Journal ArticleDOI
TL;DR: The present position statement offers a state‐of‐the‐art summary of what is known about risk factors for potential pathophysiological mechanisms, clinical presentation of, and diagnosis and management of PPCM.
Abstract: Peripartum cardiomyopathy (PPCM) is a cause of pregnancy-associated heart failure. It typically develops during the last month of, and up to 6 months after, pregnancy in women without known cardiovascular disease. The present position statement offers a state-of-the-art summary of what is known about risk factors for potential pathophysiological mechanisms, clinical presentation of, and diagnosis and management of PPCM. A high index of suspicion is required for the diagnosis, as shortness of breath and ankle swelling are common in the peripartum period. Peripartum cardiomyopathy is a distinct form of cardiomyopathy, associated with a high morbidity and mortality, but also with the possibility of full recovery. Oxidative stress and the generation of a cardiotoxic subfragment of prolactin may play key roles in the pathophysiology of PPCM. In this regard, pharmacological blockade of prolactin offers the possibility of a disease-specific therapy.

Journal ArticleDOI
TL;DR: Successful CEA for asymptomatic patients younger than 75 years of age reduces 10-year stroke risks and net benefits were significant both for those on lipid-lowering therapy and for those not, and both for men and for women up to 75 year of age at entry.

Journal ArticleDOI
03 Jun 2010-Blood
TL;DR: It is estimated that in excess of 300,000 children are born each year with a severe inherited disorder of hemoglobin and that approximately 80% of these births occur in low- or middle-income countries, with the true magnitude of this burden still unknown.

Journal ArticleDOI
TL;DR: The power of genome-wide analysis of complex binding patterns and combinatorial interactions for ten key regulators of blood stem/progenitor cells is reported, providing the most comprehensive TF data set for any adult stem/ Progenitor cell type to date.

Journal ArticleDOI
TL;DR: The authors discusses shortcomings of the usual blood pressure hypothesis, provides background to accompanying reports on the importance of blood pressure variability in prediction of risk of vascular events and in accounting for benefits of antihypertensive drugs, and draws attention to clinical implications and directions for future research.

Journal ArticleDOI
TL;DR: At 1 year, surgery and best medical therapy improved patient self-reported quality of life more than best medical Therapy alone in patients with advanced Parkinson's disease, but surgery is not without risk and targeting of patients most likely to benefit might be warranted.
Abstract: Summary Background Surgical intervention for advanced Parkinson's disease is an option if medical therapy fails to control symptoms adequately. We aimed to assess whether surgery and best medical therapy improved self-reported quality of life more than best medical therapy alone in patients with advanced Parkinson's disease. Methods The PD SURG trial is an ongoing randomised, open-label trial. At 13 neurosurgical centres in the UK, between November, 2000, and December, 2006, patients with Parkinson's disease that was not adequately controlled by medical therapy were randomly assigned by use of a computerised minimisation procedure to immediate surgery (lesioning or deep brain stimulation at the discretion of the local clinician) and best medical therapy or to best medical therapy alone. Patients were analysed in the treatment group to which they were randomised, irrespective of whether they received their allocated treatment. The primary endpoint was patient self-reported quality of life on the 39-item Parkinson's disease questionnaire (PDQ-39). Changes between baseline and 1 year were compared by use of t tests. This trial is registered with Current Controlled Trials, number ISRCTN34111222. Findings 366 patients were randomly assigned to receive immediate surgery and best medical therapy (183) or best medical therapy alone (183). All patients who had surgery had deep brain stimulation. At 1 year, the mean improvement in PDQ-39 summary index score compared with baseline was 5·0 points in the surgery group and 0·3 points in the medical therapy group (difference −4·7, 95% CI −7·6 to −1·8; p=0·001); the difference in mean change in PDQ-39 score in the mobility domain between the surgery group and the best medical therapy group was −8·9 (95% CI −13·8 to −4·0; p=0·0004), in the activities of daily living domain was −12·4 (−17·3 to −7·5; p Interpretation At 1 year, surgery and best medical therapy improved patient self-reported quality of life more than best medical therapy alone in patients with advanced Parkinson's disease. These differences are clinically meaningful, but surgery is not without risk and targeting of patients most likely to benefit might be warranted. Funding UK Medical Research Council, Parkinson's UK, and UK Department of Health.

Journal ArticleDOI
28 May 2010-Immunity
TL;DR: It is found that STAT3 bound to multiple genes involved in Th17 cell differentiation, cell activation, proliferation, and survival, regulating both expression and epigenetic modifications, and orchestrates multiple critical aspects of T cell function in inflammation and homeostasis.

Journal ArticleDOI
TL;DR: Drug-class effects on interindividual variation in blood pressure can account for differences in effects of antihypertensive drugs on risk of stroke independently of effects on mean SBP.

Journal ArticleDOI
Lesley Jones1, Peter Holmans1, Marian L. Hamshere1, Denise Harold1, Valentina Moskvina1, Dobril Ivanov1, Andrew Pocklington1, Richard Abraham1, Paul Hollingworth1, Rebecca Sims1, Amy Gerrish1, Jaspreet Singh Pahwa1, Nicola L. Jones1, Alexandra Stretton1, Angharad R. Morgan1, Simon Lovestone2, John Powell3, Petroula Proitsi3, Michelle K. Lupton3, Carol Brayne4, David C. Rubinsztein4, Michael Gill5, Brian A. Lawlor5, Aoibhinn Lynch5, Kevin Morgan6, Kristelle Brown6, Peter Passmore7, David Craig7, Bernadette McGuinness7, Stephen Todd7, Clive Holmes8, David G. Mann9, A. David Smith10, Seth Love11, Patrick G. Kehoe11, Simon Mead12, Nick C. Fox12, Martin N. Rossor12, John Collinge12, Wolfgang Maier13, Frank Jessen13, Britta Schürmann13, Hendrik van den Bussche14, Isabella Heuser14, Oliver Peters14, Johannes Kornhuber15, Jens Wiltfang16, Martin Dichgans17, Lutz Frölich18, Harald Hampel17, Harald Hampel19, Michael Hüll20, Dan Rujescu17, Alison Goate21, John S. K. Kauwe22, Carlos Cruchaga21, Petra Nowotny21, John C. Morris21, Kevin Mayo21, Gill Livingston, Nicholas Bass, Hugh Gurling, Andrew McQuillin, Rhian Gwilliam23, Panos Deloukas23, Ammar Al-Chalabi3, Christopher Shaw3, Andrew B. Singleton24, Rita Guerreiro24, Thomas W. Mühleisen13, Markus M. Nöthen13, Susanne Moebus16, Karl-Heinz Jöckel16, Norman Klopp, H.-Erich Wichmann17, Eckhard Rüther25, Minerva M. Carrasquillo26, V. Shane Pankratz26, Steven G. Younkin26, John Hardy, Michael Conlon O'Donovan1, Michael John Owen1, Julie Williams1 
15 Nov 2010-PLOS ONE
TL;DR: Independent evidence from two large studies demonstrates that these processes related to cholesterol metabolism and the innate immune response are aetiologically relevant, and suggests that they may be suitable targets for novel and existing therapeutic approaches.
Abstract: Background 1Late Onset Alzheimer's disease (LOAD) is the leading cause of dementia. Recent large genome-wide association studies (GWAS) identified the first strongly supported LOAD susceptibility genes since the discovery of the involvement of APOE in the early 1990s. We have now exploited these GWAS datasets to uncover key LOAD pathophysiological processes. Methodology We applied a recently developed tool for mining GWAS data for biologically meaningful information to a LOAD GWAS dataset. The principal findings were then tested in an independent GWAS dataset. Principal Findings We found a significant overrepresentation of association signals in pathways related to cholesterol metabolism and the immune response in both of the two largest genome-wide association studies for LOAD. Significance Processes related to cholesterol metabolism and the innate immune response have previously been implicated by pathological and epidemiological studies of Alzheimer's disease, but it has been unclear whether those findings reflected primary aetiological events or consequences of the disease process. Our independent evidence from two large studies now demonstrates that these processes are aetiologically relevant, and suggests that they may be suitable targets for novel and existing therapeutic approaches.

Journal ArticleDOI
TL;DR: In contrast to the original method, ShMOLLI showed no dependence on heart rates for long T1 values, with estimates characterized by a constant 4% underestimation for T1 = 800-2700 ms, and is an efficient method that generates immediate, high-resolution myocardial T1-maps in a short breath-hold with high precision.
Abstract: T1 mapping allows direct in-vivo quantitation of microscopic changes in the myocardium, providing new diagnostic insights into cardiac disease. Existing methods require long breath holds that are demanding for many cardiac patients. In this work we propose and validate a novel, clinically applicable, pulse sequence for myocardial T1-mapping that is compatible with typical limits for end-expiration breath-holding in patients. The Shortened MOdified Look-Locker Inversion recovery (ShMOLLI) method uses sequential inversion recovery measurements within a single short breath-hold. Full recovery of the longitudinal magnetisation between sequential inversion pulses is not achieved, but conditional interpretation of samples for reconstruction of T1-maps is used to yield accurate measurements, and this algorithm is implemented directly on the scanner. We performed computer simulations for 100 ms

Journal ArticleDOI
TL;DR: The opposite effects of calcium-channel blockers and beta blockers on variability of blood pressure account for the disparity in observed effects on risk of stroke and expected effects based on mean blood pressure.
Abstract: Summary Background Analyses of some randomised trials show that calcium-channel blockers reduce the risk of stroke more than expected on the basis of mean blood pressure alone and that β blockers are less effective than expected. We aimed to investigate whether the effects of these drugs on variability in blood pressure might explain these disparities in effect on stroke risk. Methods The Anglo-Scandinavian Cardiac Outcomes Trial Blood Pressure Lowering Arm (ASCOT-BPLA) compared amlodipine-based regimens with atenolol-based regimens in 19 257 patients with hypertension and other vascular risk factors and the Medical Research Council (MRC) trial compared atenolol-based and diuretic-based regimens versus placebo in 4396 hypertensive patients aged 65–74 years. We expressed visit-to-visit variability of blood pressure during follow-up in the two trials as standard deviation (SD) and as transformations uncorrelated with mean blood pressure. For ASCOT-BPLA, we also studied within-visit variability and variability on 24 h ambulatory blood-pressure monitoring (ABPM). Results In ASCOT-BPLA, group systolic blood pressure (SBP) SD was lower in the amlodipine group than in the atenolol group at all follow-up visits (p Interpretation The opposite effects of calcium-channel blockers and β blockers on variability of blood pressure account for the disparity in observed effects on risk of stroke and expected effects based on mean blood pressure. To prevent stroke most effectively, blood-pressure-lowering drugs should reduce mean blood pressure without increasing variability; ideally they should reduce both. Funding None.

Journal ArticleDOI
TL;DR: In this paper, the pathogenesis of pre-eclampsia can be related to defined immune mechanisms that are appropriate to the fetomaternal frontier, and the first pregnancy preponderance and partner specificity can be explained by this model.
Abstract: Pre-eclampsia develops in stages, only the last being the clinical illness This is generated by a non-specific, systemic (vascular), inflammatory response, secondary to placental oxidative stress and not by reactivity to fetal alloantigens However, maternal adaptation to fetal (paternal alloantigens) is crucial in the earlier stages A pre-conceptual phase involves maternal tolerization to paternal antigens by seminal plasma After conception, regulatory T cells, interacting with indoleamine 2,3-dioxygenase, together with decidual NK cell recognition of fetal HLA-C on extravillous trophoblast may facilitate placental growth by immunoregulation Complete failure of this mechanism would cause miscarriage, while partial failure would cause poor placentation and dysfunctional uteroplacental perfusion The first pregnancy preponderance and partner specificity of pre-eclampsia can be explained by this model For the first time, the pathogenesis of pre-eclampsia can be related to defined immune mechanisms that are appropriate to the fetomaternal frontier Now, the challenge is to prove the detail

Journal ArticleDOI
27 Aug 2010-Immunity
TL;DR: It is demonstrated that T cell reactivity to IL-23 was critical for development of intestinal pathology, but not for systemic inflammation.

Journal ArticleDOI
TL;DR: This work uses a comprehensive data assembly of HbS allele frequencies to generate the first evidence-based map of the worldwide distribution of the gene in a Bayesian geostatistical framework and finds geographical support for the malaria hypothesis globally.
Abstract: It has been 100 years since the first report of sickle haemoglobin (HbS). More than 50 years ago, it was suggested that the gene responsible for this disorder could reach high frequencies because of resistance conferred against malaria by the heterozygous carrier state. This traditional example of balancing selection is known as the 'malaria hypothesis'. However, the geographical relationship between the transmission intensity of malaria and associated HbS burden has never been formally investigated on a global scale. Here, we use a comprehensive data assembly of HbS allele frequencies to generate the first evidence-based map of the worldwide distribution of the gene in a Bayesian geostatistical framework. We compare this map with the pre-intervention distribution of malaria endemicity, using a novel geostatistical area-mean comparison. We find geographical support for the malaria hypothesis globally; the relationship is relatively strong in Africa but cannot be resolved in the Americas or in Asia.

Journal ArticleDOI
01 Feb 2010-Brain
TL;DR: In the mouse model, immunoglobulin G from neuromyelitis optica patients does not require pre-existing central nervous system inflammation to produce lesions and co-injection of immunoglOBulin G with human complement reproduces the key histological features of neuromyELitis optic and aquaporin-4 is necessary and sufficient to exert its effect.
Abstract: Neuromyelitis optica is an inflammatory demyelinating disease of the central nervous system associated with autoantibodies against the glial water channel protein aquaporin-4. It has recently been reported that immunoglobulin from neuromyelitis optica patients injected peripherally does not cause lesions in naive rats, but only when pre-existing central nervous system inflammation is present. Here, we investigated whether immunoglobulin G from aquaporin-4-autoantibody-positive neuromyelitis optica patients has the potential to damage the central nervous system either alone or in the presence of human complement. Immunoglobulin G from neuromyelitis optica patients did not activate mouse complement and was not pathogenic when injected into mouse brain. However, co-injection of immunoglobulin G from neuromyelitis optica patients with human complement produced neuromyelitis optica-like lesions in mice. Within 12 h of co-injecting immunoglobulin G from neuromyelitis optica patients and human complement, there was a striking loss of aquaporin-4 expression, glial cell oedema, myelin breakdown and axonal injury, but little intra-parenchymal inflammation. At 7 days, there was extensive inflammatory cell infiltration, perivascular deposition of activated complement components, extensive demyelination, loss of aquaporin-4 expression, loss of reactive astrocytes and neuronal cell death. In behavioural studies, mice injected with immunoglobulin G from neuromyelitis optica patients and human complement into the right hemisphere preferentially turned to the right at 7 days. No brain inflammation, demyelination or right-turning behaviour was seen in wild-type mice that received immunoglobulin G from non-neuromyelitis optica patients with human complement, or in aquaporin-4-null mice that received immunoglobulin G from neuromyelitis optica patients with human complement. We conclude that co-injection of immunoglobulin G from neuromyelitis optica patients with human complement reproduces the key histological features of neuromyelitis optica and that aquaporin-4 is necessary and sufficient for immunoglobulin G from neuromyelitis optica patients to exert its effect. In our mouse model, immunoglobulin G from neuromyelitis optica patients does not require pre-existing central nervous system inflammation to produce lesions.

Journal ArticleDOI
01 Jan 2010-Stroke
TL;DR: In the first study of the prognosis of ≥50% asymptomatic carotid stenosis to be initiated in the last 10 years, the risk of stroke on intensive contemporary medical treatment was low.
Abstract: Background and Purpose— The annual risk of ischemic stroke distal to ≥50% asymptomatic carotid stenoses was ≈2% to 3% in early cohort studies and subsequent randomized trials of endarterectomy. This risk might have fallen in recent years owing to improvements in medical treatment, but there are no published prognostic data from studies initiated within the last 10 years. Methods— In a population-based study of all patients with transient ischemic attack (TIA) or stroke in the Oxford Vascular Study, we studied the risk of TIA and stroke in patients with ≥50% contralateral asymptomatic carotid stenoses recruited consecutively from 2002 to 2009 and given intensive contemporary medical treatment. Results— Of 1153 consecutively imaged patients presenting with stroke or TIA, 101 (8.8%) had ≥50% asymptomatic carotid stenoses (mean age, 75 years; 39% women; 40% age ≥80 years). During 301 patient-years of follow-up (mean, 3 years), there were 6 ischemic events in the territory of an asymptomatic stenosis, 1 minor ...

Journal ArticleDOI
01 Jun 2010-Stroke
TL;DR: The MoCA picked up substantially more cognitive abnormalities after transient ischemic attack and stroke than the Mini-Mental State Examination, demonstrating deficits in executive function, attention, and delayed recall.
Abstract: Background and Purpose— The Mini-Mental State Examination (MMSE) is insensitive to mild cognitive impairment and executive function. The more recently developed Montreal Cognitive Assessment (MoCA), an alternative, brief 30-point global cognitive screen, might pick up more cognitive abnormalities in patients with cerebrovascular disease. Methods— In a population-based study (Oxford Vascular Study) of transient ischemic attack and stroke, the MMSE and MoCA were administered to consecutive patients at 6-month or 5-year follow-up. Accepted cutoffs of MMSE <27 and MoCA <26 were taken to indicate cognitive impairment. Results— Of 493 patients, 413 (84%) were testable. Untestable patients were older (75.5 versus 69.9 years, P<0.001) and often had dysphasia (24%) or dementia (15%). Although MMSE and MoCA scores were highly correlated (r2=0.80, P<0.001), MMSE scores were skewed toward higher values, whereas MoCA scores were normally distributed: median and interquartile range 28 (26 to 29) and 23 (20 to 26), resp...

Journal ArticleDOI
TL;DR: A cohort of patients with recent‐onset temporal lobe epilepsy caused by LE was studied to test for GAD antibody positivity and response to immunotherapies.
Abstract: Objective Antibodies to glutamic acid decarboxylase (GAD) have been described in a few patients with temporal lobe epilepsies consistent with limbic encephalitis (LE). We studied a cohort of patients with recent-onset temporal lobe epilepsy caused by LE to test for GAD antibody positivity and response to immunotherapies. Methods Over a period of 3.75 years, 138 patients aged ≥18 years investigated at the Department of Epileptology, University of Bonn, for recent-onset epilepsy were prospectively collected and studied for cliniconeuroradiological features of LE, autoantibodies, and treatment responses. Results Fifty-three adult patients fulfilled the criteria for LE: (1) limbic signs and symptoms for ≤5 years and (2) brain MRI revealing mediotemporal encephalitis (T2/fluid attenuated inversion recovery hyperintensity without atrophy). Nine had high-titer GAD antibodies; 10 had voltage-gated potassium channel (VGKC) antibodies. Patients with GAD antibodies were younger (median age, 23 years; range, 17-66 years) (p = 0.003) and presented with seizures only, whereas polymorphic limbic features were more common in the VGKC antibody-positive group (p < 0.001). None had tumors. Patients with GAD antibodies more frequently had cerebrospinal fluid oligoclonal bands (p = 0.009) and intrathecal secretion of the specific antibody (p = 0.01). Following monthly intravenous methylprednisolone pulses, GAD antibodies remained highly elevated in 6/6 patients, whereas VGKC antibodies normalized in 6/9 patients (p = 0.03). Despite more intense anticonvulsive treatment in the GAD antibody-positive group (p = 0.01), none of these patients became seizure free, unlike all of the patients with VGKC antibodies (p < 0.001). Interpretation High-titer GAD antibodies define a form of nonparaneoplastic LE. This is a chronic, nonremitting disorder and should be included in the differential diagnosis of patients with TLE and mediotemporal encephalitis. Therapeutic trials of other immunotherapies should be undertaken. ANN NEUROL 2010;67:470–478

Journal ArticleDOI
12 Aug 2010-Trials
TL;DR: This work proposes a framework that prioritizes the analysis and reporting of multivariate risk-based HTE and suggests that other subgroup analyses should be explicitly labeled either as primary sub group analyses (well-motivated by prior evidence and intended to produce clinically actionable results) or secondary (exploratory) subgroups analyses (performed to inform future research).
Abstract: Mounting evidence suggests that there is frequently considerable variation in the risk of the outcome of interest in clinical trial populations. These differences in risk will often cause clinically important heterogeneity in treatment effects (HTE) across the trial population, such that the balance between treatment risks and benefits may differ substantially between large identifiable patient subgroups; the "average" benefit observed in the summary result may even be non-representative of the treatment effect for a typical patient in the trial. Conventional subgroup analyses, which examine whether specific patient characteristics modify the effects of treatment, are usually unable to detect even large variations in treatment benefit (and harm) across risk groups because they do not account for the fact that patients have multiple characteristics simultaneously that affect the likelihood of treatment benefit. Based upon recent evidence on optimal statistical approaches to assessing HTE, we propose a framework that prioritizes the analysis and reporting of multivariate risk-based HTE and suggests that other subgroup analyses should be explicitly labeled either as primary subgroup analyses (well-motivated by prior evidence and intended to produce clinically actionable results) or secondary (exploratory) subgroup analyses (performed to inform future research). A standardized and transparent approach to HTE assessment and reporting could substantially improve clinical trial utility and interpretability.