Serum proteomic profiling at diagnosis predicts clinical course, and need for intensification of treatment in inflammatory bowel disease.

BACKGROUND: Success in personalized medicine in complex disease is critically dependent on biomarker discovery. We profiled serum proteins using a novel proximity extension assay [PEA] to identify diagnostic and prognostic biomarkers in inflammatory bowel disease [IBD]. METHODS: We conducted a prospective case-control study in an inception cohort of 552 patients [328 IBD, 224 non-IBD], profiling proteins recruited across six centres. Treatment escalation was characterized by the need for biological agents or surgery after initial disease remission. Nested leave-one-out cross-validation was used to examine the performance of diagnostic and prognostic proteins. RESULTS: A total of 66 serum proteins differentiated IBD from symptomatic non-IBD controls, including matrix metallopeptidase-12 [MMP-12; Holm-adjusted p = 4.1 × 10-23] and oncostatin-M [OSM; p = 3.7 × 10-16]. Nine of these proteins are associated with cis-germline variation [59 independent single nucleotide polymorphisms]. Fifteen proteins, all members of tumour necrosis factor-independent pathways including interleukin-1 (IL-1) and OSM, predicted escalation, over a median follow-up of 518 [interquartile range 224-756] days. Nested cross-validation of the entire data set allowed characterization of five-protein models [96% comprising five core proteins ITGAV, EpCAM, IL18, SLAMF7 and IL8], which define a high-risk subgroup in IBD [hazard ratio 3.90, confidence interval: 2.43-6.26], or allowed distinct two- and three-protein models for ulcerative colitis and Crohn's disease respectively. CONCLUSION: We have characterized a simple oligo-protein panel that has the potential to identify IBD from symptomatic controls and to predict future disease course. Further prospective work is required to validate our findings.

Faecal microbiota signatures of IBD and their relation to diagnosis, disease phenotype, inflammation, treatment escalation and anti-TNF response in a European Multicentre Study (IBD-Character).

METHOD: We examined faecal samples, using the GA-map™ Dysbiosis Test, to associate gut microbiota composition with Crohn's disease (CD) and ulcerative colitis (UC) and to identify markers for future biomarker identification. We conducted a prospective case-control study (EU-ref. no. 305676) in an inception cohort of 324 individuals (64 CD, 84 UC, 116 symptomatic non-IBD controls and 44 healthy controls) across five European centres and examined 54 predetermined bacterial markers. We categorized patients according to the Montreal Classification and calculated the dysbiosis index (DI). Non-parametric tests were used to compare groups and the Bonferroni correction to adjust for multiple comparisons. RESULTS: The fluorescent signals (FSSs) for Firmicutes and Eubacterium hallii were lower in inflammatory bowel disease (IBD) vs. symptomatic controls (p<.05). FSS for Firmicutes, Lachnospiraceae, Eubacterium hallii and Ruminococcus albus/bromii were lower, whereas the signal for Bacteroides Fragilis was higher in UC vs. symptomatic controls (p<.05). FSS was higher for Bifidobacterium spp., Eubacterium hallii, Actinobacteria and Firmicutes among patients with ulcerative proctitis, compared to extensive colitis (p<.05). In CD, we observed no association with disease location. The DI correlated with faecal-calprotectin in both CD and in UC (p<.001). In terms of treatment escalation and anti-TNF response, differences were observed for some bacterial markers, but none of these associations were statistically significant. CONCLUSION: Our data reveal that the GA-map™ Dysbiosis Test holds the potential to characterize the faecal microbiota composition and to assess the degree of dysbiosis in new-onset IBD. On the other hand, our results cannot demonstrate any proven diagnostic or predictive value of this method to support clinical decision making.

Whole Blood Profiling of T-cell-Derived microRNA Allows the Development of Prognostic models in Inflammatory Bowel Disease.

BACKGROUND: MicroRNAs [miRNAs] are cell-specific small non-coding RNAs that can regulate gene expression and have been implicated in inflammatory bowel disease [IBD] pathogenesis. Here we define the cell-specific miRNA profiles and investigate its biomarker potential in IBD. METHODS: In a two-stage prospective multi-centre case control study, next generation sequencing was performed on a discovery cohort of immunomagnetically separated leukocytes from 32 patients (nine Crohn's disease [CD], 14 ulcerative colitis [UC], eight healthy controls) and differentially expressed signals were validated in whole blood in 294 patients [97 UC, 98 CD, 98 non-IBD, 1 IBDU] using quantitative PCR. Correlations were analysed with phenotype, including need for early treatment escalation as a marker of progressive disease using Cox proportional hazards. RESULTS: In stage 1, each leukocyte subset [CD4+ and CD8+ T-cells and CD14+ monocytes] was analysed in IBD and controls. Three specific miRNAs differentiated IBD from controls in CD4+ T-cells, including miR-1307-3p [p = 0.01], miR-3615 [p = 0.02] and miR-4792 [p = 0.01]. In the extension cohort, in stage 2, miR-1307-3p was able to predict disease progression in IBD (hazard ratio [HR] 1.98, interquartile range [IQR]: 1.20-3.27; logrank p = 1.80 × 10-3), in particular CD [HR 2.81; IQR: 1.11-3.53, p = 6.50 × 10-4]. Using blood-based multimarker miRNA models, the estimated chance of escalation in CD was 83% if two or more criteria were met and 90% for UC if three or more criteria are met. INTERPRETATION: We have identified and validated unique CD4+ T-cell miRNAs that are differentially regulated in IBD. These miRNAs may be able to predict treatment escalation and have the potential for clinical translation; further prospective evaluation is now indicated.

[Dizziness and vertigo in a tertiary ENT emergency department]. / Schwindelerkrankungen in einem tertiären HNO-Notfallzentrum.

BACKGROUND: Although vestibular symptoms are amongst the most frequent reasons for seeking emergency medical help, many patients remain undiagnosed. OBJECTIVE: In this cross-sectional study, we investigated the spectrum of vertigo and dizziness in a tertiary ear, nose, and throat (ENT) emergency department (ED). Furthermore, we investigated the attendant symptoms, clinical signs, and the diagnostic tests performed. METHODS: We screened all ED reports from 01/2013 to 12/2013 for adult patients with vestibular symptoms referred to the ENT department. RESULTS: In total, we found 2596 cases with reported vestibular symptoms in the ED as a main or accompanying complaint. Of these, 286 were referred to the ENT specialist directly (n = 98) or via other major medical specialties (n = 188). Benign paroxysmal positional vertigo (BPPV) was the most frequent diagnosis in our study (n = 46, 16.1%), followed by vestibular neuritis (n = 44, 15.4%), otitis media (n = 20, 7%), and 9 patients (3.1%) had an ischemic stroke or a transient ischemic attack. In 70 (24.5%) cases, dizziness was not further specified. CONCLUSION: BPPV is the most frequent diagnosis seen in the ED; however, physicians need to document nystagmus more precisely and perform diagnostic tests systematically, in order to make an accurate diagnosis. To avoid misdiagnoses, ED physicians and ENT specialists should be able to recognize central signs in patients with an acute vestibular syndrome. Every fourth patient does not receive a definitive diagnosis. Diagnostic ED workup for patients with dizziness needs further improvement.

Integrative epigenome-wide analysis demonstrates that DNA methylation may mediate genetic risk in inflammatory bowel disease.

Epigenetic alterations may provide important insights into gene-environment interaction in inflammatory bowel disease (IBD). Here we observe epigenome-wide DNA methylation differences in 240 newly-diagnosed IBD cases and 190 controls. These include 439 differentially methylated positions (DMPs) and 5 differentially methylated regions (DMRs), which we study in detail using whole genome bisulphite sequencing. We replicate the top DMP (RPS6KA2) and DMRs (VMP1, ITGB2 and TXK) in an independent cohort. Using paired genetic and epigenetic data, we delineate methylation quantitative trait loci; VMP1/microRNA-21 methylation associates with two polymorphisms in linkage disequilibrium with a known IBD susceptibility variant. Separated cell data shows that IBD-associated hypermethylation within the TXK promoter region negatively correlates with gene expression in whole-blood and CD8+ T cells, but not other cell types. Thus, site-specific DNA methylation changes in IBD relate to underlying genotype and associate with cell-specific alteration in gene expression.

Real-time computer-based visual feedback improves visual acuity in downbeat nystagmus - a pilot study.

BACKGROUND: Patients with downbeat nystagmus syndrome suffer from oscillopsia, which leads to an unstable visual perception and therefore impaired visual acuity. The aim of this study was to use real-time computer-based visual feedback to compensate for the destabilizing slow phase eye movements. METHODS: The patients were sitting in front of a computer screen with the head fixed on a chin rest. The eye movements were recorded by an eye tracking system (EyeSeeCam®). We tested the visual acuity with a fixed Landolt C (static) and during real-time feedback driven condition (dynamic) in gaze straight ahead and (20°) sideward gaze. In the dynamic condition, the Landolt C moved according to the slow phase eye velocity of the downbeat nystagmus. The Shapiro-Wilk test was used to test for normal distribution and one-way ANOVA for comparison. RESULTS: Ten patients with downbeat nystagmus were included in the study. Median age was 76 years and the median duration of symptoms was 6.3 years (SD +/- 3.1y). The mean slow phase velocity was moderate during gaze straight ahead (1.44°/s, SD +/- 1.18°/s) and increased significantly in sideward gaze (mean left 3.36°/s; right 3.58°/s). In gaze straight ahead, we found no difference between the static and feedback driven condition. In sideward gaze, visual acuity improved in five out of ten subjects during the feedback-driven condition (p = 0.043). CONCLUSIONS: This study provides proof of concept that non-invasive real-time computer-based visual feedback compensates for the SPV in DBN. Therefore, real-time visual feedback may be a promising aid for patients suffering from oscillopsia and impaired text reading on screen. Recent technological advances in the area of virtual reality displays might soon render this approach feasible in fully mobile settings.

MicroRNAs: new players in IBD.

MicroRNAs (miRNAs) are small non-coding RNAs, 18-23 nucleotides long, which act as post-transcriptional regulators of gene expression. miRNAs are strongly implicated in the pathogenesis of many common diseases, including IBDs. This review aims to outline the history, biogenesis and regulation of miRNAs. The role of miRNAs in the development and regulation of the innate and adaptive immune system is discussed, with a particular focus on mechanisms pertinent to IBD and the potential translational applications.

Thiopurine withdrawal during sustained clinical remission in inflammatory bowel disease: relapse and recapture rates, with predictive factors in 237 patients.

BACKGROUND: Thiopurines (azathioprine and mercaptopurine) remain integral to most medical strategies for maintaining remission in Crohn's disease (CD) and ulcerative colitis (UC). Indefinite use of these drugs is tempered by long-term risks. While clinical relapse is noted frequently following drug withdrawal, there are few published data on predictive factors. AIM: To investigate the success of planned thiopurine withdrawal in patients in sustained clinical remission to identify rates and predictors of relapse. METHODS: This was a multicentre retrospective cohort study from 11 centres across the UK. Patients included had a definitive diagnosis of IBD, continuous thiopurine use ≥3 years and withdrawal when in sustained clinical remission. All patients had a minimum of 12 months follow-up post drug withdrawal. Primary and secondary end points were relapse at 12 and 24 months respectively. RESULTS: 237 patients were included in the study (129 CD; 108 UC). Median duration of thiopurine use prior to withdrawal was 6.0 years (interquartile range 4.4-8.4). At follow-up, moderate/severe relapse was observed in 23% CD and 12% UC patients at 12 months, 39% CD and 26% UC at 24 months. Relapse rate at 12 months was significantly higher in CD than UC (P = 0.035). Elevated CRP at withdrawal was associated with higher relapse rates at 12 months for CD (P = 0.005), while an elevated white cell count was predictive at 12 months for UC (P = 0.007). CONCLUSION: Thiopurine withdrawal in the context of sustained remission is associated with a 1-year moderate-to-severe relapse rate of 23% in Crohn's disease and 12% in ulcerative colitis.

Consensus paper: management of degenerative cerebellar disorders.

Treatment of motor symptoms of degenerative cerebellar ataxia remains difficult. Yet there are recent developments that are likely to lead to significant improvements in the future. Most desirable would be a causative treatment of the underlying cerebellar disease. This is currently available only for a very small subset of cerebellar ataxias with known metabolic dysfunction. However, increasing knowledge of the pathophysiology of hereditary ataxia should lead to an increasing number of medically sensible drug trials. In this paper, data from recent drug trials in patients with recessive and dominant cerebellar ataxias will be summarized. There is consensus that up to date, no medication has been proven effective. Aminopyridines and acetazolamide are the only exception, which are beneficial in patients with episodic ataxia type 2. Aminopyridines are also effective in a subset of patients presenting with downbeat nystagmus. As such, all authors agreed that the mainstays of treatment of degenerative cerebellar ataxia are currently physiotherapy, occupational therapy, and speech therapy. For many years, well-controlled rehabilitation studies in patients with cerebellar ataxia were lacking. Data of recently published studies show that coordinative training improves motor function in both adult and juvenile patients with cerebellar degeneration. Given the well-known contribution of the cerebellum to motor learning, possible mechanisms underlying improvement will be outlined. There is consensus that evidence-based guidelines for the physiotherapy of degenerative cerebellar ataxia need to be developed. Future developments in physiotherapeutical interventions will be discussed including application of non-invasive brain stimulation.

Molecular breeding of transgenic white clover (Trifolium repens L.) with field resistance to Alfalfa mosaic virus through the expression of its coat protein gene.

Viral diseases, such as Alfalfa mosaic virus (AMV), cause significant reductions in the productivity and vegetative persistence of white clover plants in the field. Transgenic white clover plants ectopically expressing the viral coat protein gene encoded by the sub-genomic RNA4 of AMV were generated. Lines carrying a single copy of the transgene were analysed at the molecular, biochemical and phenotypic level under glasshouse and field conditions. Field resistance to AMV infection, as well as mitotic and meiotic stability of the transgene, were confirmed by phenotypic evaluation of the transgenic plants at two sites within Australia. The T(0) and T(1) generations of transgenic plants showed immunity to infection by AMV under glasshouse and field conditions, while the T(4) generation in an agronomically elite 'Grasslands Sustain' genetic background, showed a very high level of resistance to AMV in the field. An extensive biochemical study of the T(4) generation of transgenic plants, aiming to evaluate the level and composition of natural toxicants and key nutritional parameters, showed that the composition of the transgenic plants was within the range of variation seen in non-transgenic populations.

A randomized trial of 4-aminopyridine in EA2 and related familial episodic ataxias.

OBJECTIVE: The therapeutic effects of 4-aminopyridine (4AP) were investigated in a randomized, double-blind, crossover trial in 10 subjects with familial episodic ataxia with nystagmus. METHODS: After randomization, placebo or 4AP (5 mg 3 times daily) was administered for 2 3-month-long treatment periods separated by a 1-month-long washout period. The primary outcome measure was the number of ataxia attacks per month; the secondary outcome measures were the attack duration and patient-reported quality of life (Vestibular Disorders Activities of Daily Living Scale [VDADL]). Nonparametric tests and a random-effects model were used for statistical analysis. RESULTS: The diagnosis of episodic ataxia type 2 (EA2) was genetically confirmed in 7 subjects. Patients receiving placebo had a median monthly attack frequency of 6.50, whereas patients taking 4AP had a frequency of 1.65 (p = 0.03). Median monthly attack duration decreased from 13.65 hours with placebo to 4.45 hours with 4AP (p = 0.08). The VDADL score decreased from 6.00 to 1.50 (p = 0.02). 4AP was well-tolerated. CONCLUSIONS: This controlled trial on EA2 and familial episodic ataxia with nystagmus demonstrated that 4AP decreases attack frequency and improves quality of life. LEVEL OF EVIDENCE: This crossover study provides Class II evidence that 4AP decreases attack frequency and improves the patient-reported quality of life in patients with episodic ataxia and related familial ataxias.

Head position during resting modifies spontaneous daytime decrease of downbeat nystagmus.

BACKGROUND: The intensity of downbeat nystagmus (DBN) decreases during the daytime when the head is in upright position. OBJECTIVE: This prospective study investigated whether resting in different head positions (upright, supine, prone) modulates the intensity of DBN after resting. METHODS: Eye movements of 9 patients with DBN due to cerebellar (n = 2) or unknown etiology (n = 7) were recorded with video-oculography. Mean slow-phase velocities (SPV) of DBN were determined in the upright position before resting at 9 am and then after 2 hours (11 am) and after 4 hours (1 pm) of resting. Whole-body positions during resting were upright, supine, or prone. The effects of all 3 resting positions were assessed on 3 separate days in each patient. RESULTS: Before resting (9 am), the average SPV ranged from 3.05 °/s to 3.6 °/s on the separate days of measurement. After resting in an upright position, the average SPV at 11 am and 1 pm was 0.65 °/sec, which was less (p < 0.05) than after resting in supine (2.1 °/sec) or prone (2.22 °/sec) positions. CONCLUSION: DBN measured during the daytime in an upright position becomes minimal after the patient has rested upright. The spontaneous decrease of DBN is less pronounced when patients lie down to rest. This indicates a modulation by otolithic input. We recommend that patients with DBN rest in an upright position during the daytime. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with DBN 2 hours of rest in the upright position decreases nystagmus more than 2 hours of rest in the supine or prone positions (relative improvement 79% upright, 33% supine, and 38% prone: p < 0.05).

Differential effects of eyes open or closed in darkness on brain activation patterns in blind subjects.

In functional brain imaging, specific task conditions can be compared to a reference condition which is often eyes-open or eyes-closed in darkness without the execution of a specific task. Previous fMRI studies in sighted subjects have shown that eyes-open in darkness, without visual stimulation, increases the relative activity in cortical ocular motor and attentional areas ("exteroceptive" state; contrast OPEN>CLOSED). By contrast, eyes-closed causes a relative signal increase in sensory systems ("interoceptive" state; contrast CLOSED>OPEN). In the present study we used fMRI to determine whether these differential brain activity states can also be found in congenitally blind subjects: there were intragroup differences between the OPEN and CLOSED conditions. These differences were, however, less pronounced and occurred in other areas than in sighted controls. The contrast OPEN>CLOSED revealed a relative signal increase in the left frontal eye field, the middle occipital gyrus bilaterally and in the anterior cingulum. Relative signal increases in occipital cortex areas and the anterior cingulum were also apparent for this contrast in the intergroup comparison (congenitally totally blind subjects vs. sighted controls). They reflect the increased attentional load or arousal during the eyes-open condition and could be indicative of a functional reorganization of the occipital cortex in the blind. The contrast CLOSED>OPEN in the congenitally totally blind subjects lead to relative activations in the somatosensory cortex bilaterally, the middle temporal gyrus on the left and the frontal gyri on the right. These activations are residues of the "interoceptive" state found in sighted controls.

[Pharmacotherapy of central oculomotor disorders]. / Pharmakotherapie zentraler Nystagmusformen.

Nystagmus causes blurred vision due to oscillopsia, as well as impaired balance. Depending on etiology, additional cerebellar and brain stem signs may occur. We present the current pharmacotherapy of the most common forms of central nystagmus: downbeat nystagmus (DBN), upbeat nystagmus (UBN), acquired pendular nystagmus (APN), and congenital nystagmus (CGN). Recommended medical therapies are aminopyridines (4-AP) for DBN and UBN, gabapentin and memantine for CGN and APN, and baclofen for periodic alternating nystagmus (PAN).

Differences in saccade-evoked brain activation patterns with eyes open or eyes closed in complete darkness.

In this study we attempted to differentiate distinct components of the saccade network, namely cortical ocular motor centers and parieto-occipital brain regions, by means of a "minimal design" approach. Using a blocked design fMRI paradigm we evaluated the BOLD changes in a 2 x 2 factorial design experiment which was performed in complete darkness: while looking straight ahead with eyes open (OPEN) or closed (CLOSED) as well as during the execution of self-initiated horizontal to-and-fro saccades with the eyes open (SACCopen) or closed (SACCclosed). Eye movements were monitored outside the scanner via electro-oculography and during scanning using video-oculography. Unintentional eye-drifts did not differ during OPEN and CLOSED and saccade frequencies, and amplitudes did not vary significantly between the two saccade conditions. The main findings of the functional imaging study were as follows: (1) Saccades with eyes open or closed in complete darkness lead to distinct differences in brain activation patterns. (2) A parieto-occipital brain region including the precuneus, superior parietal lobule, posterior part of the intraparietal sulcus (IPS), and cuneus was relatively deactivated during saccades performed with eyes closed but not during saccades with eyes open or when looking straight ahead. This could indicate a preparatory state for updating spatial information, which is active during saccades with eyes open even without actual visual input. The preparatory state is suppressed when the eyes are closed during the saccades. (3) Selected ocular motor areas, not including the parietal eye field (PEF), show a stronger activation during SACCclosed than during SACCopen. The increased effort involved in performing saccades with eyes closed, perhaps due to the unusualness of the task, may be the cause of this increased activation.

Structural and functional MRIs disclose cerebellar pathologies in idiopathic downbeat nystagmus.

BACKGROUND: Neurologic disorders in which the etiology and pathogenesis are not yet understood are termed idiopathic. Downbeat nystagmus (DBN) is a frequent eye movement disorder that clinically manifests with oscillopsia and postural instability. Forty percent of patients with DBN are classified as having idiopathic DBN, because no underlying pathology can be demonstrated by conventional MRI or laboratory tests. METHODS: We evaluated gray matter brain volumes of 11 patients with idiopathic DBN and compared them to those of healthy controls using voxel-based morphometry. In a second, functional MRI experiment, patients and controls performed downward smooth pursuit eye movements (DOWN), which were then compared with straight-ahead fixation of a stationary target (MID). RESULTS: Small areas of localized gray matter atrophy were detected in the lateral cerebellar hemispheres (lobule VI) and ocular motor vermis of patients with idiopathic DBN, but not in the flocculus and paraflocculus. The functional imaging data, however, revealed reduced activation in the parafloccular lobule and in the ponto-medullary brainstem of the patients when they performed smooth pursuit eye movements downwards. CONCLUSIONS: The applied specialized imaging and data analysis techniques disclosed pathologies in an idiopathic eye movement disorder. The focal atrophy found in the vermal and lateral cerebellar regions in downbeat nystagmus (DBN) may lead to deficits in smooth pursuit eye movement initiation, which in turn causes hypofunction of the parafloccular lobe, associated with DBN. Our data are in line with experiments in primates showing that ablation of the floccular and parafloccular lobes disrupts smooth pursuit and causes DBN.