Perisaccadic compression in two-saccade sequences

Around the onset of a saccade toward a target, localization judgments are systematically biased toward the saccade endpoint. This perisaccadic compression is thought to be related to transsaccadic reorganization and due to interfering motor signals in visual maps. It has, however, only been investigated for saccades targeting a single target. Here, we examined whether saccade-sequence programming to stationary target(s) would affect the pattern of localization judgments of a briefly flashed stimulus. We presented saccade targets that could induce either a single saccade or two-saccade sequences and we flashed a bar around saccade onsets. For all two-saccade-sequence conditions, we showed that localization judgments of the stimulus flashed around the first saccade onset are biased toward an intermediate position between the two-saccade landing position, indicating the influence of the second saccade's parallel planning. This implies that motor-planning signals are most likely responsible for perisaccadic compression than motor execution feedback.     

A contemporary neuroscience approach compared to biomedically focused education combined with symptom-contingent exercise therapy in people with chronic whiplash associated disorders: a randomized controlled trial protocol

BackgroundTo address the need for a better treatment of chronic whiplash associated disorders (WAD), a contemporary neuroscience approach can be proposed.ObjectiveTo examine the effectiveness of a contemporary neuroscience approach, comprising pain neuroscience education, stress management, and cognition-targeted exercise therapy versus conventional physical therapy for reducing disability (primary outcome measure) and improving quality of life and reducing pain, central sensitization, and psychological problems (secondary outcome measures) in people with chronic WAD.MethodsThe study is a multi-center, two-arm randomized, controlled trial with 1-year follow-up and will be performed in two university-based and one regional hospital. People with chronic WAD (n = 120) will be recruited. The experimental group will receive pain neuroscience education followed by cognition-targeted exercise therapy, and stress management. The control group will receive biomedically focused education followed by graded and active exercise therapy focusing on muscle endurance, strength, and flexibility, and ergonomic principles. The treatment will have a duration of 16 weeks. Functional status (Neck Disability Index) is the primary outcome measure. Secondary outcome measures include quality of life, pain, central sensitization, and psychological and socio-economic factors. In addition, electroencephalography will measure brain activity at rest and during a conditioned pain modulation paradigm. Assessments will take place at baseline, immediately post-treatment and at 6 and 12 months follow-up.ConclusionsThis study will examine whether a contemporary neuroscience approach is superior over conventional physical therapy for improving functioning, quality of life, and reducing pain, central sensitization, and psychological problems in people with chronic WAD.     

Course of iron parameters in HFE‐hemochromatosis patients during initial treatment with erythrocytapheresis compared to phlebotomy

Current treatment for newly diagnosed patients with hereditary hemochromatosis (HH) and iron overload consist of weekly phlebotomy or less frequent and more personalized erythrocytapheresis. Previous observations during phlebotomy suggest an increase in intestinal iron uptake caused by lowering of hepcidin as a result of intensive bloodletting. It is not known whether such an effect is present or even more pronounced using erythrocytapheresis since a larger amount of iron is extracted per procedure. In this study we aimed to assess the effect of erythrocytapheresis on the course of iron parameters, with special focus on serum hepcidin. We performed a retrospective proof‐of‐principle observational study, comparing serum iron parameters in 12 males during the depletion phase using either phlebotomy (n = 6) or erythrocytapheresis (n = 6). Decreases in serum ferritin over time were similar for both treatments but more pronounced using erythrocytapheresis when expressed per treatment procedure. Hemoglobin did not change during erythrocytapheresis, whereas during phlebotomy decreased with 10%. Increase of erythropoietin and soluble transferrin receptor and decrease in transferrin saturation were similar for both treatments. Reduction in serum hepcidin was higher (50% versus 25% of initial value) and occurred more early using phlebotomy (10 versus 20 weeks after start). In aggregate, compared to phlebotomy, the less frequent and more personalized erythrocytapheresis leads to a more pronounced decrease in serum ferritin per treatment procedure, without a larger decrease in serum hepcidin. This may be clinically relevant and may prevent an increase in intestinal iron uptake and an ensuing vicious circle of more frequent treatment procedures. J. Clin. Apheresis 31:564–570, 2016. © 2015 Wiley Periodicals, Inc.     

S4-based voltage sensors have three major conformations

Voltage sensors containing the charged S4 membrane segment display a gating charge vs. voltage (Q-V) curve that depends on the initial voltage. The voltage-dependent phosphatase (Ci-VSP), which does not have a conducting pore, shows the same phenomenon and the Q-V recorded with a depolarized initial voltage is more stable by at least 3RT. The leftward shift of the Q-V curve under prolonged depolarization was studied in the Ci-VSP by using electrophysiological and site-directed fluorescence measurements. The fluorescence shows two components: one that traces the time course of the charge movement between the resting and active states and a slower component that traces the transition between the active state and a more stable state we call the relaxed state. Temperature dependence shows a large negative enthalpic change when going from the active to the relaxed state that is almost compensated by a large negative entropic change. The Q-V curve midpoint measured for pulses that move the sensor between the resting and active states, but not long enough to evolve into the relaxed states, show a periodicity of 120 degrees, indicating a 3(10) secondary structure of the S4 segment when determined under histidine scanning. We hypothesize that the S4 segment moves as a 3(10) helix between the resting and active states and that it converts to an alpha-helix when evolving into the relaxed state, which is most likely to be the state captured in the crystal structures.     

Congenital leukaemia: the Dutch experience and review of the literature

We reviewed Dutch patients and those described in the literature with congenital leukaemia in the past 25 years, with the intention to obtain an overview of the characteristics of this rare disease. Among the 117 patients reviewed, acute myeloid leukaemia (AML) was more frequent (64%) than acute lymphoblastic leukaemia (ALL, 21%). Most patients had a high leukaemic cell load with hepatosplenomegaly, leukaemia cutis and hyperleucocytosis. Cytogenetic abnormalities were found in the majority of the patients tested (72%); 11q23 abnormalities were found in less than half of them (42%). The probability of overall survival at 24 months was only 23%. When congenital AML and ALL were compared, clinical characteristics and overall survival were not significantly different. However, in patients at risk, the probability of event-free survival (EFS) and disease-free survival (DFS) were significantly higher in AML than in ALL, 43% versus 13% and 68% versus 0% respectively. Among the congenital AML cases, six spontaneous remissions have been described. In conclusion, the clinical characteristics of congenital leukaemia differ from those of leukaemia in older children and prognosis is generally poor. Once complete remission is achieved, patients with AML fare better than those with ALL. Chemotherapy for congenital leukaemia needs improvement to increase the sustained remission rate.     

Hemispheric asymmetry in the effects of substantia nigra lesioning on lymphocyte reactivity in mice.

Asymmetry in brain modulation of the immune system has previously been demonstrated at the neocortex level. In these experiments, the possibility of subcortical immunomodulation was investigated. In mice the substantia nigra was lesioned using the neurotoxin 6-hydroxydopamine. Four and six weeks after left or right lesions of the substantia nigra, spleen lymphocyte mitogenesis was slightly depressed or enhanced respectively as compared to sham operated controls. Differences appeared when comparing left and right lesioned groups. However, natural killer cell activity was unaffected by unilateral lesions of the substantia nigra. These results show that asymmetrical brain modulation may occur at the sub-cortical level and suggest that central dopamine is involved in neuroimmunomodulation.     

Accommodation on downward gaze.

A study was conducted with the purpose of examining the possible effects of vertical and horizontal eye movements upon accommodation. A special Badal stimulator was made which was vertically rotatable around the center of an eye. The stimulator was attached to the Three-Dimensional Optometer III (TDOIII), which could measure accommodation, eye movement, and pupil diameter simultaneously. The reliability of the TDOIII measurements of accommodation was checked by comparing with a stigmatoscope measurement. Three young males served as subjects. A small but definite near accommodation was measured dynamically in association with vertical eye movement. We believe this to be the first report of this finding. The amount of near accommodation with downgaze showed a tendency to decrease when the target was brought near.     

The use of LHRH analogs in ovulation induction

The use of LH-RH agonists is appropriate for the stimulation of ovulation. In contrast, in the case of induction of ovulation in a patient with deficient ovulation, suppression of influences of the hypothalamo-pituitary axis does not modify the pathological condition responsible for the ovulatory anomaly.