Alaryngeal speakers (speakers in whom the larynx has been removed) have inconsistent control over acoustic parameters such as F(0) and duration. This study investigated whether proficient tracheoesophageal and oesophageal speakers consistently convey phrase boundaries. It was further investigated if these alaryngeal speakers used the same hierarchy of acoustic boundary cues that is found in normal speakers.
View Article and Find Full Text PDFThe vestibulo-ocular reflex (VOR) is characterized by a short-latency, high-fidelity eye movement response to head rotations at frequencies up to 20 Hz. Electrophysiological studies of medial vestibular nucleus (MVN) neurons, however, show that their response to sinusoidal currents above 10 to 12 Hz is highly nonlinear and distorted by aliasing for all but very small current amplitudes. How can this system function in vivo when single cell response cannot explain its operation? Here we show that the necessary wide VOR frequency response may be achieved not by firing rate encoding of head velocity in single neurons, but in the integrated population response of asynchronously firing, intrinsically active neurons.
View Article and Find Full Text PDFExactly 100 years ago, Louis Lapicque published a paper on the excitability of nerves that is often cited in the context of integrate-and-fire neurons. We discuss Lapicque's contributions along with a translation of the original publication.
View Article and Find Full Text PDFWe compared the measurement properties of a performance test (Juvenile Arthritis Functional Assessment Scale; JAFAS) with a questionnaire-based instrument (Childhood Health Assessment Questionnaire; CHAQ) to measure functional ability in patients with juvenile idiopathic arthritis on the level of individual items. In 28 consecutive children visiting an outpatient paediatrics clinic, the JAFAS (range 0-20) and CHAQ (range 0-3) were applied, and measures of disease activity and joint range of motion (ROM) were determined. Twenty-eight children with a median age of 10 years and median disease duration of 3.
View Article and Find Full Text PDFObjective: To assess the safety and efficacy of intensive immunosuppression followed by T cell-depleted autologous hematopoietic stem cell transplantation (ASCT) for induction of disease remission in children with refractory progressive juvenile idiopathic arthritis (JIA).
Methods: Twenty-two patients with progressive refractory JIA were followed up over a median period of 80 months after pretreatment with intensive immunosuppression followed by ASCT in a multicenter, prospective, phase II clinical trial. Hematopoietic stem cells were harvested from the patients' bone marrow, depleted of T cells, and kept frozen until used for ASCT.
The rodent head-direction (HD) system, which codes for the animal's head direction in the horizontal plane, is thought to be critically involved in spatial navigation. Electrophysiological recording studies have shown that HD cells can anticipate the animal's HD by up to 75-80 ms. The origin of this anticipation is poorly understood.
View Article and Find Full Text PDFLichen sclerosus is a chronic disorder of skin and mucosa which affects patients of all age groups, particularly women, but also men. It is most commonly seen on the female genital skin, but it also occurs on extragenital areas. Most patients complain of itching and, less frequently, a burning sensation, dyspareunia, dysuria and painful defecation are reported.
View Article and Find Full Text PDFObjectives: A previous 24-week randomised trial demonstrated that sulfasalazine (SSZ) treatment was superior to placebo (PLAC) in suppressing disease activity in patients with oligo- and polyarticular onset juvenile idiopathic arthritis (JIA). The current study determines the long-term outcome of the trial participants and evaluates whether the benefits of SSZ allocation are sustained over time.
Methods: Between 2001 and 2003, 32 SSZ and 29 PLAC patients (90% of all patients) were prospectively examined clinically and by chart review, median 9 years (range 7 to 10) after trial inclusion.
This study investigated whether a novel ionogenic substance, containing amongst others zinc and rubidium (PHI-5; Dermagenics Inc, Memphis, TN, USA), could improve the healing of full-thickness skin wounds. Uniform wounds were created on the right flank of guinea pigs. Micro-grooved silicone rubber membranes, containing 0 (controls), 1.
View Article and Find Full Text PDFObjective: To determine whether vaccinations aggravate the course of autoimmune diseases such as juvenile idiopathic arthritis (JIA) and whether the immune response to vaccinations may be hampered by immunosuppressive therapy for the underlying disease.
Methods: In this multicenter cohort study, 234 patients with JIA (ages 1-19 years) were vaccinated with meningococcal serogroup C (MenC) conjugate to protect against serogroup C disease (caused by Neisseria meningitidis). Patients were followed up for disease activity for 1 year, from 6 months before until 6 months after vaccination.
Throughout our lives we acquire general knowledge about the world (semantic memory) while also retaining memories of specific events (episodic memory). Although these two forms of memory have been dissociated on the basis of neuropsychological data, it is clear that they typically function together during normal cognition. The goal of the present study was to investigate this interaction.
View Article and Find Full Text PDFBackground: Publications in peer-reviewed journals are the main determinants of research rating and funding. The present study assesses worldwide scientific contributions in the field of surgical research.
Methods: Fifteen major surgical journals were selected for a bibliometric search in Medline/PubMed over a 6-year period (2000-2005).
Objective: To use the Pediatric Rheumatology International Trials Organization (PRINTO) core set of outcome measures to develop a validated definition of improvement for the evaluation of response to therapy in juvenile systemic lupus erythematosus (SLE).
Methods: Thirty-seven experienced pediatric rheumatologists from 27 countries, each of whom had specific experience in the assessment of juvenile SLE patients, achieved consensus on 128 patient profiles as being clinically improved or not improved. Using the physicians' consensus ratings as the gold standard measure, the chi-square, sensitivity, specificity, false-positive and false-negative rates, area under the receiver operating characteristic curve, and kappa level of agreement for 597 candidate definitions of improvement were calculated.
Experiments have shown that the intrinsic excitability of neurons is not constant, but varies with physiological stimulation and during various learning paradigms. We study a model of Hebbian synaptic plasticity which is supplemented with intrinsic excitability changes. The excitability changes transcend time delays and provide a memory trace.
View Article and Find Full Text PDFThe sparsity of photons at very low light levels necessitates a nonlinear synaptic transfer function between the rod photoreceptors and the rod-bipolar cells. We examine different ways to characterize the performance of the pathway: the error rate, two variants of the mutual information, and the signal-to-noise ratio. Simulation of the pathway shows that these approaches yield substantially different performance at very low light levels and that maximizing the signal-to-noise ratio yields the best performance when judged from simulated images.
View Article and Find Full Text PDFOur experience in 6 cases of thrombosis of the palmar digital veins is presented and an additional 20 from the world literature are reviewed. All our patients were female and suffered from a tender, bluish nodule on the palmar aspect of a digit at or distally to the proximal interphalangeal joint. In the first 2 cases, the diagnosis was confirmed on histology following excision.
View Article and Find Full Text PDFTreatment of systemic vasculitides is usually based on the use of corticosteroids and other immunosuppressive drugs. We describe a 10-year-old girl with systemic vasculitis resistant to immunosuppressive treatment who had a rapid and impressive response to treatment with infliximab.
View Article and Find Full Text PDFObjective: To evaluate the sensitivity to change of a newly developed radiologic assessment tool, the Dijkstra score, and to develop a numeric composite score and progressor classification scheme to apply in juvenile idiopathic arthritis (JIA) trials.
Methods: A placebo-controlled trial of sulfasalazine (SSZ) in patients with oligoarticular- and polyarticular-onset JIA yielded the data for this study. Data were obtained from 418 sets of radiographs of the clinically involved and contralateral joints (at study entry and at 6 months' followup) from 66 JIA patients.
In this paper a patient with a non-Hodgkin's lymphoma (NHL) and paraneoplastic pemphigus (PNP) is described. PNP is a very rare, painful mucocutaneous intraepithelial blistering disease associated with occult or confirmed malignancy. Patients with PNP show severe, progressive mucocutaneous disease with a high mortality rate, because of drug-induced infectious complications.
View Article and Find Full Text PDFObjective: To evaluate the safety and efficacy of autologous stem cell transplantation (ASCT) for refractory juvenile idiopathic arthritis (JIA).
Design: Retrospective analysis of follow up data on 34 children with JIA who were treated with ASCT in nine different European transplant centres. Rheumatological evaluation employed a modified set of core criteria.
Epidermal keratinocytes are heterogeneous and can be divided into stem cells (strong beta1-integrin expression) with unlimited clonogenic potential, transient amplifying cells (weaker beta1-integrin expression) with restricted proliferative capacity and terminally differentiated cells (no beta1-integrin expression) that have lost the capacity to divide. We tested the hypothesis that cell kinetic characteristics of the epidermal subpopulations differ. Single cell suspensions from small human skin punch biopsies were sorted flow cytometrically into a beta1-integrin weakly positive (dim) and strongly positive (bright) subpopulation and the clonogenic potential was compared in cell culture experiments.
View Article and Find Full Text PDFFeline amyloidosis is an uncommon disorder caused by deposits of amyloid in a variety of organs. Most frequently encountered types are amyloid derived of pancreatic islet amyloid polypeptide (AIAPP) in older cats and of the apolipoprotein, apo-serum amyloid A (AA) in Abyssinian/Somali (Aby) and Siamese/Oriental (Siam) cats occurring at a relatively young age. For the AA protein of the Aby, Siam and domestic shorthair cat (DSH) breed different amino acid sequences have been described.
View Article and Find Full Text PDFInformation in a spike train is limited by variability in the spike timing. This variability is caused by noise from several sources including synapses and membrane channels; but how deleterious each noise source is and how they affect spike train coding is unknown. Combining physiology and a multicompartment model, we studied the effect of synaptic input noise and voltage-gated channel noise on spike train reliability for a mammalian ganglion cell.
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