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Filaments are ubiquitous within the microscopic world, occurring in biological and industrial environments and displaying a varied dynamics. Their wide range of applications has spurred the development of a branch of asymptotics focused on the behaviour of filaments, called slender-body theory (SBT). Slender-body theories are computationally efficient and focus on the mechanics of an isolated fibre that is slender and not too curved. However, SBTs that work beyond these limits are needed to explore complex systems. Recently, we developed tubular-body theory (TBT), an approach like SBT that allows the hydrodynamic traction on any isolated fibre in a viscous fluid to be determined exactly. This paper extends TBT to model fibres near plane interfaces by performing a similar expansion on the single-layer boundary integrals (BIs) for bodies by a plane interface. This provides a well-behaved SBT inspired approach for fibres by interfaces with a similar versatility to the BIs but without the singular kernels. The derivation of the new theory, called tubular-body theory for interfaces (TBTi), also establishes a criterion for the convergence of the TBTi series representation. The TBTi equations are solved numerically using a approach similar to boundary element methods (BEMs), called TBTi-BEM, to investigate the properties of TBTi empirically. The TBTi-BEM is found to compare favourably with an existing BEM and the lubrication singularity on a sphere, suggesting TBTi is valid for all separations. Finally, we simulate the hydrodynamics of helices beneath a free interface and a plane wall to demonstrate the applicability of the technique. [ABSTRACT FROM AUTHOR]

We describe a case of an adolescent male with Niemann-Pick Type C (NP-C), a neurodegenerative lysosomal lipid storage disorder, who presented with recurrent catatonia which required repeated treatment with electroconvulsive therapy (ECT). During the ECT-course, seizure threshold increased substantially, leading to questions about the influence of NP-C on neuronal excitability. In this exemplary ECT-patient, NP-C was diagnosed not until after the first ECT-course when initial psychopharmacology for catatonia had failed and antipsychotics and benzodiazepines showed significant side-effects. Clinicians should be aware of NP-C in patients referred for ECT, especially in the case of treatment resistance, neurological symptoms and intolerance of psychopharmacological drugs. As was shown in our NP-C patient, ECT can be repeatedly effective for catatonic features. In the literature, effectiveness of ECT in patients with NP-C has sparsely been reported. This case demonstrates that detection of NP-C is beneficial for patients because more optimal treatment with ECT can be provided earlier without further exposure to side-effects. [ABSTRACT FROM AUTHOR]

Paediatric movement disorders (PMDs) comprise a large group of disorders (tics, myoclonus, tremor, dystonia, chorea, Parkinsonism, ataxia), often with mixed phenotypes. Determination of the underlying aetiology can be difficult given the broad differential diagnosis and the complexity of the genotype–phenotype relationships. This can make the diagnostic process time‐consuming and difficult. In this overview, we present a diagnostic approach for PMDs, with emphasis on genetic causes. This approach can serve as a framework to lead the clinician through the diagnostic process in eight consecutive steps, including recognition of the different movement disorders, identification of a clinical syndrome, consideration of acquired causes, genetic testing including next‐generation sequencing, post‐sequencing phenotyping, and interpretation of test results. The aim of this approach is to increase the recognition and diagnostic yield in PMDs. What this paper adds: An up‐to‐date description and diagnostic framework for testing of paediatric movement disorders is presented.The framework helps to determine which patients will benefit from next‐generation sequencing. What this paper adds: An up‐to‐date description and diagnostic framework for testing of paediatric movement disorders is presented.The framework helps to determine which patients will benefit from next‐generation sequencing. [ABSTRACT FROM AUTHOR]

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Background and Aims The objective of this study was to examine the modulating effect of an appendectomy on the disease course of therapy-refractory ulcerative colitis [UC] patients, and to analyse appendiceal pathological characteristics predictive of pathological response. Methods Patients with therapy-refractory UC, and referred for proctocolectomy, were invited to undergo laparoscopic appendectomy first. The primary end points were clinical response after 3 and 12 months. Secondary end points were endoscopic remission, failure, and pathologic response. Appendiceal specimens, and pre- and post-operative biopsies were histologically graded according to the validated Geboes score. Results Thirty patients [53% male] with a median age of 40 (interquartile range [IQR], 33–47) underwent appendectomy, with a median preoperative total Mayo score of 9 [IQR, 8–11]. After 12 months, 9 patients [30%] had lasting clinical response, of whom 5 [17%] were in endoscopic remission. Pathological evaluation was possible in 28 patients. After a median of 13.0 weeks [range 7–51], pathological response was seen in 13 patients [46%], with a median decrease of 2 points [range 1–3]. Appendiceal inflammation was highly predictive of pathological response when compared with no inflammation or extensive ulcerations [85% vs 20%, p = 0.001]. Conclusions Appendectomy was effective in one-third of therapy-refractory UC patients, with a substantial proportion of patients demonstrating complete endoscopic remission after 1 year. Pathological response was seen in almost 50% of patients and was related to active inflammation in the appendix, limited disease, and shorter disease duration. These early results suggest that there is a UC patient group that may benefit from appendectomy. [ABSTRACT FROM AUTHOR]

Background: Niemann-Pick type C (NP-C) is a rare autosomal recessive progressive neurodegenerative disorder caused by mutations in the NP-C 1 or 2 gene. Besides visceral symptoms, presentation in adolescent and adult onset variants is often with neurological symptoms. The most frequently reported presenting symptoms of NP-C in adulthood are psychiatric symptoms (38 %), cognitive decline (23 %) and ataxia (20 %). Myoclonus can be present, but its value in early diagnosis and the evolving clinical phenotype in NP-C is unclear. In this paper we present eight Dutch cases of NP-C of whom five with myoclonus.Methods: Eight patients with genetically confirmed NP-C were recruited from two Dutch University Medical Centers. A structured interview and neuropsychological tests (for working and verbal memory, attention and emotion recognition) were performed. Movement disorders were assessed using a standardized video protocol. Quality of life was evaluated by questionnaires (Rand-36, SIP-68, HAQ). In four of the five patients with myoclonic jerks simultaneous EEG with EMG was performed.Results: A movement disorder was the initial neurological symptom in six patients: three with myoclonus and three with ataxia. Two others presented with psychosis. Four experienced cognitive deficits early in the course of the disease. Patients showed cognitive deficits in all investigated domains. Five patients showed myoclonic jerks, including negative myoclonus. In all registered patients EEG-EMG coherence analysis and/or back-averaging proved a cortical origin of myoclonus. Patients with more severe movement disorders experienced significantly more physical disabilities.Conclusions: Presenting neurological symptoms of NP-C include movement disorders, psychosis and cognitive deficits. At current neurological examination movement disorders were seen in all patients. The incidence of myoclonus in our cohort was considerably higher (63 %) than in previous publications and it was the presenting symptom in 38 %. A cortical origin of myoclonus was demonstrated. Our data suggest that myoclonus may be overlooked in patients with NP-C. All patients scored significantly lower on physical domains of HRQoL. Symptomatic treatment of movement disorders may improve physical functioning and subsequently HRQoL. [ABSTRACT FROM AUTHOR]

We present measurements of the galaxy bias b and the galaxy-matter cross-correlation coefficient r for the Baryon Oscillation Spectroscopic Survey LOWZ luminous red galaxy sample. Using a new statistical weak lensing analysis of the Red Cluster Sequence Lensing Survey (RCSLenS), we find the bias properties of this sample to be higher than previously reported with b = 2.45+0.05 -0.05 and r = 1.64+0.17 -0.16 on scales between 3 and 20 arcmin. We repeat the measurement for angular scales of 20 arcmin = = 70 arcmin, which yields b = 2.39+0.07 -0.07 and r = 1.24+0.26 -0.25. This is the first application of a data compression analysis using a complete set of discrete estimators for galaxy-galaxy lensing and galaxy clustering. As cosmological data sets grow, our new method of data compression will become increasingly important in order to interpret joint weak lensing and galaxy clustering measurements and to estimate the data covariance. In future studies, this formalism can be used as a tool to study the large-scale structure of the Universe to yield a precise determination of cosmological parameters. [ABSTRACT FROM AUTHOR]