To document perinatal events, brain imaging, neurophysiology and clinical outcome in term infants with early postnatal collapse (PNC).
Tertiary referral centre, retrospective case review (1993-2006).
...Infants born at > or =36 weeks' gestation with early (<72 h) PNC. Peri-partum and post-collapse data were collated with clinical, electrophysiological, neuroimaging and autopsy data and neurodevelopmental outcome.
Twelve infants were studied; median gestation 39 weeks (36-41), birth weight 3150 g (1930-4010). Ten were born vaginally (including occipitoposterior (1), breech (2), water birth (2), ventouse/forceps (3)), and two by emergency caesarean section. Median Apgar scores were 9 (3-9) and 10 (8-10) at 1 and 5 min; median cord pH was 7.29 (7.18-7.34). All were thought to be well after birth. The median age at PNC was 75 min (10 min to 55 h). All infants required extensive resuscitation. The median pH after PNC was 6.75 (6.39-7.05). Seven infants became severely encephalopathic, with severely abnormal EEG/aEEG recorded within 12 h. MRI showed acute severe hypoxic-ischaemic injury. All died. One infant showed rapid recovery, had mild encephalopathy, and good outcome. Four infants had severe respiratory illness, normal background EEG, and MRI showing slight white matter change (n = 3) or a small infarction (n = 1). All had a good 2-year outcome.
In this term cohort, early PNC was generally followed by severe encephalopathy, acute central grey matter injury and poor outcome, or severe respiratory illness, slight white matter change and good outcome. Early EEG and MRI predicted outcome accurately. However, no antepartum, intrapartum or other aetiological factors were identified. Further investigation is needed in larger PNC cohorts.
Objective Vein graft arterialization results in activation of the mitogen-activated protein kinases (MAPKs) extracellular signal-regulated kinases-1 and -2 (ERK1/2), which have been implicated in ...cell proliferation, migration, and apoptosis. The goal of our study was to characterize the effect of MAPK inhibition on intimal hyperplasia (IH) in arterialized vein grafts in hypercholesterolemic rabbits. Methods Reversed bilateral jugular vein to common carotid artery interposition grafts were constructed in 16 New Zealand White rabbits. The veins were incubated for 30 min prior to grafting with either the synthetic ERK1/2 activation inhibitor UO126 or the control vehicle. Vein graft and control jugular vein were harvested 3 h, 1 d, and 28 d after arterialization for histological and biochemical analyses. Results Treatment with UO126 was associated with 31% reduction in mean intimal area (1.68 ± 0.78 mm2 versus 2.44 ± 1.65 mm2 ; mean ± SD; P = 0.036) relative to controls. The intima-to-media ratio of UO126-treated vein grafts decreased by 29% (0.53 ± 0.04 versus 0.74 ± 0.06; mean ± SD; P < 0.01) compared to controls, vehicle-treated vein grafts. There was also significant increase in apoptosis in UO126-treated vein graft medial cell layer at 1 d. Conclusion Topical administration of UO126 before vein grafting significantly decreases IH in arterialized vein grafts in hypercholesterolemic rabbits. These results may have significant implications for the development of strategies aimed at blocking or reducing IH in bypass grafts. Therefore, further evaluation of this simple strategy to improve vein graft patency following coronary artery or peripheral vascular bypass surgery is warranted.
Introduction Bipolar Disorder (BD) is a chronic mood disorder with a prevalence estimated around 1–2%. Bipolar patients may experience social and working residual impairment even during euthymia. ...Furthermore, specific cognitive deficits, particularly involving working memory (WM), may persist during eythymia as well. Aim To evaluate the possible presence of cognitive and functional differences between euthymic bipolar subjects vs. healthy controls during euthymia by means of a WM task at fMRI associated with neuropsychological evaluations. Methods A sample of 30 subjects aged between 20 and 45 years (15 with BD and 15 controls) underwent fMRI examination at 3 Tesla with tasks of working memory (n-back). All participants received a neuropsychological evaluation, inlcuding Stroop Color-Word Interference test, Tower of London, Trail Making Test, Wisconsin Card Sorting Test and Verbal Fluency Test. Comparison tests were performed using statistical software SPSS and SPM5. Results The performance of the control group was significantly higher than both at the n-back task and at the neuropsychological tests. The full-factorial analysis of fMRI data showed a hypoactivation in bipolar patients in particular hippocampus and thalamus, associated with increased involvement of areas not involved in the frontal-parietal networks classically associated with WM. Conclusions The results seem to confirm the existence of a residual dysfunction during euthymia phase in BD, suggesting two distinct patterns of activation in the two groups studied, both from a neuropsychological point of view and from a neuroimaging perspective.
The strength–duration function is a classic measure of neural excitability. When studied on peripheral motor axons it reflects the intrinsic nodal membrane properties, and its time‐constant (τSD or ...chronaxie) predominantly depends on non‐voltage‐gated, rest Na+ inward conductances. We assessed the strength–duration curve of ulnar motor axons in 22 nerves of healthy controls, in 18 nerves of patients with multifocal motor neuropathy with conduction blocks (MMN), and in 19 nerves of patients with motor neurone disease (MND). The compound muscle action potential (CMAP) was smaller in nerves of both groups of patients than in controls (P < 0.05). The rheobasic current (rh50%) mean ± standard deviation (SD) was higher in patients with MMN than in controls (13.3 ± 16.3 mA; controls 4.7 ± 1.7 mA, P < 0.05). The τSD was differentially abnormal in the nerves of the two groups of patients: it was prolonged in the nerves of patients with MND for ≥40 years (227.2 ± 34.5 µs; controls 190.9 ± 51.0 µs, P < 0.05), but it was shortened in the nerves of patients with MMN (146.5 ± 55.4 µs; controls 208.6 ± 51.2 µs, P < 0.05) who had not been treated recently with high‐dose intravenous immunoglobulin (IVIg). Nerves of patients with recently treated MMN (<6 weeks) who were under the therapeutic effect of IVIg had a normal τSD. Our results suggest that, probably due to an immuno‐mediated rest Na+ channel dysfunction, Na+ conductances are reduced in MMN. This abnormality is a function of the time after the last IVIg treatment and involves also the axonal membrane outside the conduction block. Conversely, in MND, possibly owing to the ionic leakage of degenerating membrane, rest Na+ conductances are increased. Measuring the strength–duration curve of the ulnar motor axons might be useful in the differential diagnosis between de novo MMN and MND.
The efficacy of deep brain stimulation of the subthalamic nucleus (STN) is dependent on the accuracy of targeting. In order to reduce the number of passes and, consequently, the duration of surgery ...and risk of bleeding, we have set up a new method based on direct magnetic resonance imaging (MRI) localisation of the STN. This procedure allows a short duration of the neurophysiological session (one or two initial tracks). Whenever a supplementary track is needed, the stimulation-induced side effects are analysed to choose from one of the remaining holes in Ben's gun. A good knowledge of anatomical structures surrounding the STN is mandatory to relate side effects to the actual position of the track. In our series of 11 patients (22 sides, 37 tracks), the most common and reproducible side effects were those characterised by motor, sensorial, oculomotor and vegetative signs and symptoms. Moreover, the therapeutic window (distance between the current intensity needed to obtain the best clinical effect and the intensity capable to induce side effects) predicted clinical efficacy in the long-term, and contributed to the choice of which among the examined tracks had to be implanted with the chronic macroelectrode.
Safety and efficacy of carotid artery stenting have still to be fully established. We propose a standardized registry of carotid artery stenting in use at our hospital to evaluate whether the ...presence of an independent neurologist performing basal, procedural and post-procedural observation increases the accuracy of outcome assessment. We collected a cohort of patients receiving carotid stenting. An external neurologist supervised the endovascular intervention and monitored the patient’s clinical conditions during procedure and follow-up time (12 months). The procedure was carried out successfully in all cases. We registered two intra-procedural strokes and two strokes within 24 h. The risk of major complications in our study was 9.1% at 30 days. Our complication rate is higher than in previous studies. These findings could be partly explained by the unemployment of distal protection devices, but also by the presence of an independent observer that might have increased the accuracy of neurological evaluation.
Although deep brain stimulation (DBS) is a clinically effective therapy for patients with advanced Parkinson's disease (PD), its physiological effects on the brain and possible actions on non-motor ...functional systems remain largely unknown. This study evaluated the effects of DBS of the subthalamic nucleus (STN) on neurophysiological variables and on cardiovascular physiology. Nine patients affected by PD undergoing chronic DBS of the STN have been studied. We performed electroencephalography (EEG), somatosensory (SEPs) and visual evoked potentials (VEPs), exteroceptive masseteric silent period and sympathetic skin response (SSR) studies with DBS ON and OFF. To assess the effects of stimulation on the cardiovascular system the tilt test and plasma renin activity were studied. When we turned the DBS OFF, both SEP N20 and the VEP P100 component increased significantly in amplitude whereas the SSR decreased in amplitude and increased in latency. Although plasma renin activity tended to increase with DBS OFF, its modification induced by postural changes and blood pressure values did not significantly differ with DBS ON and OFF. We conclude that DBS of the STN in PD, besides inducing a clinical improvement, induces several non-motor effects.
PDF
