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Epilepsy surgery is recommended in selected patients with Tuberous Sclerosis Complex (TSC). However, reports on predictive factors of seizure outcome are variable. Here we report on seizure and cognitive outcome of 35 TSC patients who received surgery for refractory epilepsy in 7 Italian centers over a period of 22 years (1997–2019). The rate of seizure-free individuals at last follow-up (mean 7.5 years, range 1–21 years) was 51%. Patients with longer follow-up (≥10 years) had a lower rate of Engel I outcome (11.1%) than those who received surgery in the last 10 years (65.4%, p = 0.003). Factors associated with Engel II, III, IV outcome in our cohort included: high number of cortical tubers (≥5); presence of subependymal nodules (SENs); seizure onset before age 1 year; and multifocal interictal epileptic discharges (IEDs) on electroencephalogram (EEG). A subset of patients evaluated with Vineland Adaptive Behaviour Scales (VABS) showed developmental gains, in line with their developmental trajectories, but no improvement in standard scores after surgery was noted. Our study demonstrates that the rates of successful seizure outcome of epilepsy surgery in TSC have improved in the last 10 years. More than half of the patients achieved seizure freedom, and a high proportion of affected individuals experienced a reduction in seizure burden and in antiseizure medications. A comprehensive assessment after surgery should be performed in TSC patients to evaluate the overall neurodevelopmental outcome, as measures that are based only on seizure control do not adequately identify the benefits of surgery on global functioning in these patients.

Development of posttraumatic stress disorder (PTSD) in parents of premature neonates has been recently described. Several source of stress have been hypothesized, however causes of PTDS and emotional reaction of the parents of premature birth hospitalized in a neonatal intensive care unit (NICU) remain largely undefined. We demonstrated that alteration of parental role and a history of anxiety have a crucial role in the development of PTSD in the parents of premature neonates. Familiarization with neonatal intensive care unit environment and increasing participation of the parents in the care of neonates during the first weeks of life improves parental role perception. Early involvement of the parents and especially of the mothers in the neonatal care, in particular if the risk of anxiety is consistent, should be considered a primary objective to prevent a PTSD.

Mutations in the gene coding for the catalytic subunit of the mitochondrial DNA (mtDNA) polymerase γ ( POLG1 ) are associated with a range of clinical syndromes characterized by secondary mtDNA defects, including mtDNA depletion and multiple mtDNA deletions.1 The phenotypic spectrum of POLG1 -associated disease ranges from fatal childhood encephalopathy with intractable epilepsy and liver failure (Alpers-Huttenlocher syndrome)2 to late-onset clinical disease affecting a single organ (for a review, see reference 3). We describe a fatal skeletal and visceral myopathy in the neonatal period associated with recessive POLG1 mutations. ### Case report. A newborn boy of healthy nonconsanguineous parents was delivered at 37 weeks’ gestation by cesarean section. His mother (primipara, 32 years old) had been admitted to our hospital 2 weeks previously because of reduced fetal intrauterine movements and polyhydramnios. The child’s birthweight was 2,330 g (

UNLABELLED Postnatal growth failure of very-low-birthweight (VLBW) infants may result from a complex interaction of genetic and environmental factors, including inadequate nutrition, morbidities affecting nutrient requirements, endocrine abnormalities and treatments. Among VLBW infants, those small for gestational age (SGA) at birth and those with postnatal growth restriction at the time of discharge are at higher risk of later growth failure and long-term consequences. Nutritional intervention with an "aggressive nutrition" during the first weeks of life may be able to minimize the interruption of nutrients that occurs at birth, and reduce as much as possible the incidence of growth restriction at the time of discharge and later. Even though aggressive parenteral and enteral nutrition appear to be effective and safe in VLBW infants, further evaluations of their long-term effect on growth and health consequences are needed. Several studies evaluating the effect of enriched nutrient formulas after hospital discharge on growth and neurodevelopment have produced conflicting results, whereas the potential deleterious long-term effects of prolonged use of high protein and/or of later catch-up growth have been questioned. In contrast, recent data seem to indicate that the use of human milk after hospital discharge could be the most beneficial diet for subsequent health and development. CONCLUSION VLBW infants SGA at birth and those with early postnatal growth restriction are at high risk of later growth failure and long-term consequences. Therefore, the first objective of early nutrition should be to reduce the incidence of growth restriction at the time of discharge. Further studies on VLBW infants to evaluate the safety and beneficial effects of prolonged dietary manipulation during the first year of life are needed.

Mechanisms underlying epileptic activities recorded from entorhinal cortex (EC) were studied through a computational model based on review of cytoarchitectonic and neurobiological data about this structure. The purpose of this study is to describe and use this model to interpret epileptiform discharge patterns recorded in an experimental model of ictogenesis (guinea pig isolated brain perfused with bicuculline). A macroscopic modeling approach representing synaptic interactions between cells subpopulations in the EC was chosen for its adequacy to mimic field potentials reflecting overall dynamics rising from interconnected cells populations. Therefore intrinsic properties of neurons were not included in the modeling design. Model parameters were adjusted from an identification procedure based on quantitative comparison between real and simulated signals. For both EC deep and superficial layers, results show that the model generates very realistic signals regarding temporal dynamics, spectral features, and cross-correlation values. These simulations allowed us to infer information about the evolution of synaptic transmission between principal cell and interneuronal populations and about connectivity between deep and superficial layers during the transition from background to ictal activity. In the model, this transition was obtained for increased excitation in deep versus superficial layers. Transitions between epileptiform activities [interictal spikes, fast onset activity (25 Hz), ictal bursting activity] were explained by changes of parameters mainly related to GABAergic interactions. Notably, the model predicted an important role of GABAa,fast- and GABAb-receptor–mediated inhibition in the generation of ictal fast onset and burst activities, respectively. These findings are discussed with respect to experimental data.

Statins have since long been reported to exert acute neuroprotection in experimental stroke models. However, crucial questions still need to be addressed as far as the timing of their cerebral effects after intravascular administration and the role played by the blood brain barrier (BBB) crossing properties. We tested the effects of an hydrophilic statin (pravastatin, 100 nM), which poorly crosses BBB under physiological conditions. Pravastatin was administered either 90 min before or immediately after transient middle cerebral artery occlusion in the in vitro isolated Guinea pig brain preparation. A multi-modal outcome assessment was performed, through electrophysiological and cerebral vascular tone recordings, MAP-2 immunohistochemistry, BBB evaluation via ZO-1/FITC-albumin analysis, AKT and ERK activation and whole-cell antioxidant capacity. Pravastatin pre-ischemic administration did not produce any significant effect. Pravastatin post-ischemic administration significantly prevented MAP-2 immunoreactivity loss in ischemic areas, increased ERK phosphorylation in the ischemic hemisphere and enhanced whole-cell antioxidant capacity. Electrophysiological parameters, vascular tone and AKT signaling were unchanged. In all tested ischemic brains, ZO-1 fragmentation and FITC albumin extravasation was observed, starting 30 min from ischemia onset, indicating loss of BBB integrity. Our findings indicate that the rapid anti-ischemic effects of intravascular pravastatin are highly dependent on BBB increased permeability after stroke.

The effects of Ni2+ were evaluated on slowly-decaying, high-voltage-activated (HVA) Ca2+ currents expressed by pyramidal neurons acutely dissociated from guinea-pig piriform cortex. Whole-cell, patch-clamp recordings were performed with Ba2+ as the charge carrier. Ni2+ blocked HVA Ba2+ currents (I Bas) with an EC50 of approximately 60 μm. Additionally, after application of nonsaturating Ni2+ concentrations, residual currents activated with substantially slower kinetics than both total and Ni2+-sensitive I Bas. None of the pharmacological components of slowly decaying, HVA currents activated with kinetics significantly different from that of total currents, indicating that the effect of Ni2+ on I Bas kinetics cannot be attributed to the preferential inhibition of a fast-activating component. The effect of Ni2+ on I Ba amplitude was voltage-independent over the potential range normally explored in our experiments (−60 to +20 mV), hence the Ni2+-dependent decrease of I Ba activation rate is not due to a voltage- and time-dependent relief from block. Moreover, Ni2+ significantly reduced I Ba deactivation speed upon repolarization, which also is not compatible with a depolarization-dependent unblocking mechanism. The dependence on Ni2+ concentration of the I Ba activation-rate reduction was remarkably different from that found for I Ba block, with an EC50 of ∼20 μm and a Hill coefficient of ∼1.73 vs.∼1.10. These results demonstrate that Ni2+, besides inhibiting the I Bas under study probably by exerting a blocking action on the pore of the underlying Ca2+ channels, also interferes with Ca2+-channel gating kinetics, and strongly suggest that the two effects depend on Ni2+ occupancy of binding sites at least partly distinct.

The control of arterial vascular tone by acetylcholine contributes to the regulation of cerebral blood flow. We analysed the effects of intraluminal application of acetylcholine (1microM) on the cerebral vascular tone by measuring changes in resistance to perfusion pressure in an isolated guinea-pig brain preparation maintained in vitro by arterial perfusion under constant flow. Acetylcholine induced a reproducible, fast-onset dilation that was prevented by the nitric oxide scavenger Methylene Blue (10microM) and by the muscarinic receptor antagonist atropine (0.1microM). Prolonged arterial perfusion with the nitric oxide synthase inhibitors N-nitro-L-arginine (1mM) and N-nitro-L-arginine methyl ester (30-100microM) induced a slowly developing increase of 25.9+/-13. 44mmHg in vascular tone and blocked the acetylcholine-induced vasodilation. In these experimental conditions, the dilation determined by the nitric oxide donor nitroprusside (0.1microM) was unaffected. In five experiments, the blockade of dilation unmasked a slow acetylcholine-mediated vasoconstriction (14.40+/-3.85mmHg) that was antagonized by atropine.The results demonstrate that acetylcholine exerts two simultaneous and opposite effects on guinea-pig cerebral vessels, characterized by a slow direct constriction concealed in physiological conditions by a fast vasodilation mediated through the release of nitric oxide by endothelial cells. Acetylcholine-mediated increase in vascular tone may play a role in aggravating cerebral perfusion when endothelial cell damage occurs during brain ischemia.

Objectives : The most relevant results of studies on the anatomo-physiological substrate of the thalamic rhythmogenic mechanisms responsible for sleep spindles and spike-wave discharges are reviewed. Methods : The reviewed experiments have been carried out in cats, rodents and other mammals with either in vivo or in vitro electrophysiological recording. Results : The rhythmic bilateral and synchronous EEG activities underlying sleep spindles and spike-wave discharges have been found to be correlated with oscillatory patterns involving mutually interconnected cortical and thalamic neurons. These rhythmic patterns are generated in thalamic neurons when the membrane potential, which is modulated by aminergic and cholinergic systems, is set to a level where the low threshold calcium current is de-inactivated. The pacemaker structure responsible for the initiation of the thalamo-cortical oscillatory activities has been identified as the reticular thalamic nucleus, a GABAergic structure projecting exclusively to the other thalamic nuclei. Experiments carried out in GAERS (genetic absence epilepsy rat from Strasbourg) demonstrated in this rat model of inherited absence epilepsy an enhancement of the pacemaker properties of the thalamic nucleus, due to a genetically determined increase in the low threshold calcium current, which is responsible for the pathological synchronization underlying spike-wave discharges. Conclusions : Recent experiments confirm the longstanding hypothesis that spindles and spike-wave discharges share common mechanisms involving thalamo-cortical circuitry. Due to its unusual anatomic and functional organization the nucleus reticularis thalami plays a crucial role as pacemaker of these rhythmic EEG activities.

The cellular mechanisms involved in the generation of spontaneous epileptiform potentials were investigated in the pirifom cortex of the in vitro isolated guinea-pig brain. A single, unilateral injection of bicuculline (150–200 nmol) in the anterior piriform cortex induced locally spontaneous interictal spikes that recurred with a period of 8.81±4.47 s and propagated caudally to the ipsi- and contralateral hemispheres. Simultaneous extra- and intracellular recordings from layer II and III principal cells showed that the spontaneous interictal spike correlates to a burst of action potentials followed by a large afterdepolarization. Intracellular application of the sodium conductance blocker, QX-314 (80 mM), abolished bursting activity and unmasked a high-threshold slow spike enhanced by the calcium chelator EGTA (50 mM). The slow spike was abolished by membrane hyperpolarization and by local perfusion with 2 mM cadmium. The depolarizing potential that followed the primary burst was reduced by arterial perfusion with the N -methyl- d -aspartate receptor antagonist, dl -2-amino-5-phosphonopentanoic acid (100–200 μM). The non- N -methyl- d -aspartate glutamate receptor antagonist, 6-cyano-7-nitroquinoxaline-2,3-dione (20 μM), completely and reversibly blocked the spontaneous spikes. The interictal spikes were terminated by a large afterpotential blocked either by intracellular QX-314 (80 mM) or by extracellular application of phaclofen and 2-hydroxysaclofen (10 and 4 mM, respectively). The present study demonstrates that, in an acute model of epileptogenesis, spontaneous interictal spikes are fostered by a primary burst of fast action potentials that ride on a regenerative high-threshold, possibly calcium-mediated spike, which activates a recurrent, glutamate-mediated potential responsible for the entrainment of adjacent and remote cortical regions. The bursting activity is controlled by a GABA B receptor-mediated inhibitory synaptic potential.

In very low birth weight (VLBW) infants careful growth and nutritional supervision are necessary in order to reduce the incidence of persistent growth retardation after 2 to 3 years of age. Recently, post-discharge formulas with higher protein, energy and mineral content has been developed with the aim to promote catch up growth and mineral accretion during the first months of life. Based upon the most recent nutritional and growth data, the authors propose guidelines for the nutrition and growth follow-up of VLBW infants after discharge from the neonatal unit.

Magistretti, Jacopo and Marco de Curtis. Low-voltage activated T-type calcium currents are differently expressed in superficial and deep layers of guinea pig piriform cortex. J. Neurophysiol. 79: 808–816, 1998. A variety of voltage-dependent calcium conductances are known to control neuronal excitability by boosting peripheral synaptic potentials and by shaping neuronal firing patterns. The existence and functional significance of a differential expression of low- and high-voltage activated (LVA and HVA, respectively) calcium currents in subpopulations of neurons, acutely isolated from different layers of the guinea pig piriform cortex, were investigated with the whole cell variant of the patch-clamp technique. Calcium currents were recorded from pyramidal and multipolar neurons dissociated from layers II, III, and IV. Average membrane capacitance was larger in layer IV cells [13.1 ± 6.2 (SD) pF] than in neurons from layers II and III (8.6 ± 2.8 and 7.9 ± 3.1 pF, respectively). Neurons from all layers showed HVA calcium currents with an activation voltage range positive to −40 mV. Neurons dissociated from layers III and IV showed an LVA calcium current with the biophysical properties of a T-type conductance. Such a current displayed the following characteristics: 1) showed maximal amplitude of 11–16 pA/pF at −30 mV, 2) inactivated rapidly with a time constant of ∼22 ms at −30 mV, and 3) was completely steady-state inactivated at −60 mV. Only a subpopulation of layer II neurons (group 2 cells; circa 18%) displayed an LVA calcium current similar to that observed in deep layers. The general properties of layer II-group 2 cells were otherwise identical to those of group 1 neurons. The present study demonstrates that LVA calcium currents are differentially expressed in neurons acutely dissociated from distinct layers of the guinea pig piriform cortex.

Selective immunostaining for calcium-binding proteins identifies subpopulations of neurons with hypothetical distinct functional roles. The neuronal localization of calcium-binding proteins calretinin, parvalbumin and calbindin is here correlated to GABA and glutamate immunoreactivity in the guinea-pig piriform cortex. In the external border of the molecular layer, neurons positive for calretinin with morphological features of Cajal-Retzius cells were found. Rare GABA immunoreactive cells were observed in the same subpial region, whereas neurons containing GABA were abundant within layers la and Ib. Aspartate- and glutamate-immunoreactive cells were also found in the outer la layer. A distinct band of calretinin-immunoreactive fibres and terminals localized in layer Ia, where the afferent fibres originating from the olfactory bulb are segregated. In layer II the number of cells containing calretinin exceeded the number of neurons positive for the anti-GABA antibody. Part of the layer II calretinin-positive neurons with pyramidal shape and large apical dendrites directed toward the surface were found to be immunoreactive for the anti-glutamate antibody on adjacent sections. Neurons in layer II immunoreactive for either parvalbumin or calbindin showed morphological features of interneurons, and their number matched the count of GABA containing cells. Calretinin-positive neurons with the general morphological features of interneurons were scarcely represented in the deep piriform cortical layers, where large multipolar and small bipolar calbindin-positive cells prevailed. The present data show that in the piriform cortex of the guinea-pig calretinin, although expressed in Cajal-Retzius-like cells as in other cortical areas, also marks a subpopulation of glutamate containing pyramidal-like neurons in layer II.

The development of long-lasting excitability changes after a single intracerebral injection of bicuculline (1 mM) in a restricted region of the anterior piriform cortex was studied by means of simultaneous intra- and extracellular recordings in the isolated guinea-pig brain preparation maintained in vitro by arterial perfusion. The transitory disinhibition induced by bicuculline revealed transient afterdischarges that were followed by the activation of a synaptic potential mediated by the recurrent propagation of the focal epileptiform activity along cortico-cortical associative fibres. The epileptiform associative potential persisted for the duration of the experiment. Both the induction and the long-term expression of the epileptiform associative potential were dependent on the activation of glutamatergic receptors of the NMDA type, as demonstrated by perfusion with the NMDA receptor antagonist 2-aminopentanoic acid (AP5) (100 microM). After bicuculline washout, piriform cortex neurons responded to afferent stimulation with a burst discharge superimposed on a paroxysmal depolarizing potential. The early component of the burst was mediated by a Ca(2+)-dependent, non-synaptic potential located at the proximal apical dendrites and soma of layer II-III cells, since (i) it was abolished by membrane hyperpolarization, (ii) it was not affected by AP5, (iii) it was correlated with a current sink in layer II, as demonstrated by current source density analysis of field potential laminar profiles, and (iv) it was abolished by cadmium (2-5 mM) applied locally in layer II. The late component of the burst response (i) coincided in time with the extracellular epileptiform associative potential, (ii) increased linearly in amplitude during membrane hyperpolarization, (iii) was blocked by AP5, and (iv) was correlated with an extracellular sink in layer Ib, where the associative fibres contact the distal apical dendrites of piriform cortex neurons. The results presented here indicate that a transient focal disinhibition promotes persistent intrinsic and synaptic excitability changes in piriform cortex neurons. These changes may be responsible for the propagation of epileptiform activity and for the induction of secondary epileptogenesis.

The relationship between interictal discharges and seizures in focal epilepsies is debated. Interictal spiking and other patterns either increase or decrease ahead of a focal seizure. It is likely that interictal events with different functional meaning with respect to seizure generation exist. The identification of the neurobiological mechanisms that control interictal patterns that exert either a precipitating or a protective action in focal ictogenesis may be relevant to develop new therapeutic strategies to anticipate or abort seizures. The differences between interictal and pre-ictal unit firing and population spike patterns will be reviewed in animal model of focal seizures and epilepsy and in recordings performed with intracranial electrodes in patients suffering from drug-resistant focal epilepsies, submitted to pre-surgical evaluation.

Macrosomic infants (birth weight4000 g) show increased risk for shoulder dystocia and associated injuries, hypoglycemia and respiratory distress. Higher risk is directly related to neonatal birth weight. High birth weight is also associated with increased risk of developing metabolic syndrome later in life. However the relation between birth weight and later-life metabolic syndrome in not linear, but "U" shaped.

In 10 children with cystic fibrosis and persisting steatorrhoea, supplementation with taurine (30-40 mg/kg/day) was given for two months as an adjunct to the usual pancreatic enzyme treatment. A three day fat and energy balance was performed in patients with cystic fibrosis, before and after the supplementation, and in seven healthy controls who did not receive taurine. Faecal fat was measured by a gravimetric method and stool energy was determined using a bomb calorimeter. Patients with cystic fibrosis, before and after taurine, and healthy controls received the same fat and energy intake (calculated by a dietitian). In patients with cystic fibrosis taurine did not produce any improvement of steatorrhoea (mean (SD) faecal fat 8.7 (3.3) v 11.2 (7.0) g/day, respectively before and after the supplementation), of faecal energy loss (0.978 (0.468) v 1.133 (0.539) MJ/day), of faecal fat expressed as percent of fat intake (13.4 (5.6) v 15.1 (9.8)%), and of faecal energy expressed as percent of energy intake (9.9 (3.6) v 11.2 (5.7)%). Healthy controls had significant lower fat (3.5 (2.3) g/day) and energy 0.576 (0.355) MJ/day faecal losses. In conclusion, taurine failed to decrease significantly fat and energy losses. Our study does not support the use of taurine supplementation in the nutritional management of cystic fibrosis.

Neuronal networks in the hippocampal and parahippocampal regions are damaged in patients affected by temporal lobe epilepsy (TLE). The consequences of the lesions are still poorly understood, but evidence suggests that interactions between the entorhinal cortex (EC) and hippocampus are changed from polysynaptic to monosynaptic, bypassing the CA3 region. In addition, the perirhinal/postrhinal cortex (PC), which normally filters the signals entering the hippocampal formation, may lose its capacity to inhibit the paroxysmal neuronal activity directed to or leaving the EC. Finally, emphasis has recently been placed on the epileptogenic role of the subiculum that is disinhibited both in epileptic animals and in TLE patients.

In vitro preparations are commonly used to study the mechanisms that regulate seizure generation in cortical structures. The complex seizure-onset patterns observed in vivo and during intracranial human recordings are seldom reproducible in brain slices, but can be evoked in more complex in vitro preparations, such as multistructure slices, the in toto hippocampus–parahippocampus of the immature rat, and the in vitro isolated adult guinea pig brain. In the latter, the connections between limbic areas are functionally preserved. We used this preparation to study the patterns of seizure activity generated in the hippocampal–parahippocampal region after acute administration of proepileptic compounds. We demonstrated that brief arterial application of bicuculline can induce interictal spiking in the piriform cortex and in the entorhinal–hippocampus, followed by seizure-like activity (in entorhinal cortex) characterized at onset by fast activity at 15–30 Hz. This ictal-onset pattern was also observed as prevalent when other compounds with diverse mechanisms of action, such as pilocarpine, pentylenetetrazole, and kainic acid, were arterially perfused in the in vitro isolated brain. These findings suggest that the observed pattern is the result of intrinsic connectivity within the limbic structures, and support the value of the in vitro isolated guinea pig brain for the study of epileptic ictogenesis.

While epilepsies affect approximately 1% of the population, seizures occur in a larger population of subjects. Clear clinical differences exist between seizures and epileptic syndromes. While repetitive seizure activity is a hallmark of epilepsy, seizures may be observed clinically as a result of pathological processes initiated outside the central nervous system (CNS). The latter include systemic diseases associated with inflammation, stroke, anoxia, and hemodynamic changes. The probability of seizure occurrence increases during iatrogenic vascular interventions (e.g., cardiopulmonary bypass or blood–brain barrier opening) due to alteration of cerebral blood flow and increased permeability of the blood–brain barrier (BBB). In this article, we present evidence suggesting the role of intravascular pathological events in setting seizure threshold.

Aim—To evaluate the eVect of fortification on the osmolality of human milk. Methods—The osmolality of 47 samples of human milk was determined at baseline, just after,and 24 hours after supplementation with five diVerent human milk fortifiers (HMF) at 4°C. Results—Ten minutes after HMF supplementation the osmolality of human milk was significantly higher than the sum of the respective values of HMF dissolved in water and human milk, measured separately at baseline (p

SummaryA 2-year, cross-sectional study was conducted to identify risk factors forCryptosporidium sp. infection in bovine farms in central Italy. Faecal sampleswere collected on 248 farms, from 2024 calves and analysed using ELISA andimmunofluorescent assay (IFA) commercial kits. In all 101 samples confirmedto be positive with IFA, the aetiological agent was identified as Cryptosporidiumparvum and a large genetic variability was detected by subtype analysis. Theprevalence of farm infection ranged from 3.4% to 35.6%. Univariate analysisshowed a number of putative risk factors, including the type of farm, stallingof calves, late supply of colostrum, number of heads and contact betweencalves and adults. However, multivariate analysis confirmed that the higher riskfor calves was associated with housing calves separately from their dams, acharacteristic practice of dairy herd, whereas calves being nursed by their dams,a characteristic of cow–calf herd resulted as a protective factor. Zoonoses and Public Health

Long-term potentiation (LTP) was investigated in the mammalian entorhinal cortex by using two in vitro preparations, the isolated brain and the entorhinal cortex slice. Hebbian and non-Hebbian types of LTP appear to be present in layer II entorhinal cortex cells as demonstrated using two protocols: (i) tetanic stimulation of the piriform-entorhinal cortex afferent pathway to generate homosynaptic potentiation and (ii) postsynaptic subthreshold rhythmic membrane potential manipulation not paired to presynaptic activation, which gives rise to non-Hebbian LTP. The induction and the expression of both types of LTP were found to be dependent on activation of N-methyl-D-aspartate receptors as shown by their sensitivity to the receptor agonist D-2-amino-5-phosphonovalerate. This is in contrast to LTP in the hippocampus [Zalutsky, R. A. & Nicoll, R. A. (1990) Science 248, 1619-1624], where LTP is expressed by quisqualate receptors. Since, in the entorhinal cortex, LTP is linked to a selective increase of the N-methyl-D-aspartate-receptor-mediated synaptic responses, this enhancement is most likely due to postsynaptic factors.

Over 40 years have elapsed since Lubchenco et al 1 proposed an anthropometric classification of neonates based on the so-called intrauterine growth charts—that is, birth weight-for-gestational age charts. The use of charts, such as those given by Lubchenco et al ,1 based on the distribution of measurements taken on neonates with different gestational age, should be restricted to the auxological assessment of babies at birth. These charts, now called neonatal anthropometric charts, must not be confused with the intrauterine growth charts, which are a tool for monitoring fetal growth, based on ultrasound measurements of anthropometric traits during pregnancy: preterm births are abnormal events and preterm neonates cannot be equated to fetuses of the same gestational age who will be born at term.2 When fetal growth studies are longitudinal, both distance and velocity intrauterine growth charts may be traced.3,4 Strictly speaking, only charts derived from longitudinal studies should be called growth charts, growth being a process extended over time. The terms SGA and intrauterine growth restriction (IUGR) are often used as synonyms, although they reflect two different concepts. SGA refers to a statistical definition, based on an auxological cross-sectional evaluation (prenatal or neonatal), and denotes a fetus or a neonate whose anthropometric variables (usually weight) are lower than a given threshold value computed on a set of infants having the same gestational age. SGA includes infants who have not achieved their own growth potential, because of maternal, uterine, placental and fetal factors,5,6 as well as small but otherwise healthy infants. IUGR refers to a clinical and functional condition and denotes fetuses unable to achieve their own growth potential: a fetus with IUGR would have been larger, without adverse environmental or genetic factors affecting growth. Such a condition can be assessed by ultrasonography during pregnancy by …

The objective was to evaluate pravastatin modulation on peripheral blood mononuclear cell (PBMC) migration across endothelial monolayers. Eleven hypercholesterolaemic patients were treated with pravastatin 20 mg/day. At baseline (T0), after 40 days (T40) and after 6 months (T 6 months) of treatment total serum cholesterol, low-density lipoprotein (LDL), high-density lipoprotein, triglycerides, C-reactive protein, as well as tumour necrosis factor-alpha (TNF-alpha) and metalloproteinases-9 plasma levels were evaluated. At the same time points the effect of pravastatin on migration of PBMCs through a monolayer of murine brain endothelial cells was studied both in basal conditions and after endothelial stimulation with recombinant mouse TNF-alpha 10 ng/ml for 24 h. Seven volunteers were used as healthy controls. Significant decreases in total cholesterol, LDL and triglycerides as well as inhibition of transmigration were observed. PBMCs transmigration in patients prior to pravastatin therapy was higher than in healthy controls. These results suggest that pravastatin could be of benefit in a spectrum of diseases characterised by extravasation of PBMCs into the central nervous system.

Olfactory information processing is mediated by synaptic connections between the olfactory bulbs (OBs) and piriform–limbic cortices. Limited accessibility using common in vivo and in vitro preparations has hindered previous attempts to define these synaptic interactions. We utilized the isolated guinea-pig brain preparation to overcome these experimental limitations. Previous studies demonstrated extensive functional preservation in this preparation maintained in vitro by arterial perfusion. Field potential laminar profiles were performed with multi-channel probes in the OB following stimulation of both the lateral olfactory tract (LOT) and the anterior piriform cortex (APC). Current-source density analysis was carried out on laminar profiles to reconstruct current sinks/sources associated with intrinsic synaptic activities. LOT stimulation induced sequentially i ) an antidromic population spike (at 2.66±0.39 ms) located in the mitral cell layer that was resistant to 100 Hz high-frequency stimulation (HFS) and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) (10 μM), ii ) a component located in the external plexiform layer at 3.85±0.63 ms that was unaffected by HFS, iii) a large amplitude potential (peak amplitude at 5.84±0.58 ms) generated in the external plexiform layer, abolished by HFS and CNQX, but not by bicuculline (50 μM), iv) a late response (onset at 20.00±2.94 ms) abolished by CNQX and enhanced by bicuculline. Stimulation of the APC also induced a late potential abolished by HFS and CNQX. Both APC-evoked and late LOT-evoked responses were abolished by a transverse cut to separate OB from APC. These results demonstrate in an isolated mammalian brain preparation the presence of reciprocal synaptic interactions between the OB and piriform cortical structures.

Objective: To analyze seizure control and treatment in pregnant women with epilepsy. Methods: Seizure control and treatment were recorded prospectively in 1,956 pregnancies of 1,882 women with epilepsy participating in EURAP, an international antiepileptic drugs (AEDs) and pregnancy registry. Results: Of all cases, 58.3% were seizure-free throughout pregnancy. Occurrence of any seizures was associated with localization-related epilepsy (OR: 2.5; 1.7 to 3.9) and polytherapy (OR: 9.0; 5.6 to 14.8) and for tonic-clonic seizures, with oxcarbazepine monotherapy (OR: 5.4; 1.6 to 17.1). Using first trimester as reference, seizure control remained unchanged throughout pregnancy in 63.6%, 92.7% of whom were seizure-free during the entire pregnancy. For those with a change in seizure frequency, 17.3% had an increase and 15.9% a decrease. Seizures occurred during delivery in 60 pregnancies (3.5%), more commonly in women with seizures during pregnancy (OR: 4.8; 2.3 to 10.0). There were 36 cases of status epilepticus (12 convulsive), which resulted in stillbirth in one case but no cases of miscarriage or maternal mortality. AED treatment remained unchanged in 62.7% of the pregnancies. The number or dosage of AEDs were more often increased in pregnancies with seizures (OR: 3.6; 2.8 to 4.7) and with monotherapy with lamotrigine (OR: 3.8; 2.1 to 6.9) or oxcarbazepine (OR: 3.7; 1.1 to 12.9). Conclusions: The majority of patients with epilepsy maintain seizure control during pregnancy. The apparently higher risk of seizures among women treated with oxcarbazepine and the more frequent increases in drug load in the oxcarbazepine and lamotrigine cohorts prompts further studies on relationships with pharmacokinetic changes. Risks associated with status epilepticus appear to be lower than previously reported.

Brain inflammation is a common event in the pathogenesis of several neurological diseases. It is unknown whether leukocyte/endothelium interactions are sufficient to promote homing of blood-borne cells into the brain compartment. The role of mononuclear cells and endothelium was analyzed in a new experimental model, the isolated guinea-pig brain maintained in vitro by arterial perfusion. This preparation allows one to investigate early steps of brain inflammation that are impracticable in vivo. We demonstrate by confocal microscopy analysis that in vitro co-perfusion of pro-inflammatory agents and pre-activated fluorescent mononuclear cells induced endothelial expression of selectins and intracellular adhesion molecule-1 in correspondence of arrested mononuclear cells, and correlates with a moderate increase in blood-brain barrier permeability. Separate perfusion of pro-inflammatory agents and mononuclear cells induced neither mononuclear cell adhesion nor adhesion molecule expression. We demonstrate that co-activation of mononuclear cells and cerebral endothelium is an essential requirement for cell arrest and adhesion in the early stages of experimental cerebral inflammation.

The processing of olfactory inputs by the parahippocampal region has a central role in the organization of memory in mammals. The olfactory input is relayed to the hippocampus via interposed synapses located in the piriform and entorhinal cortices. Whether olfactory afferents directly or indirectly project to other areas of the parahippocampal region beside the entorhinal cortex (EC) is uncertain. We performed an electrophysiological and imaging study of the propagation pattern of the olfactory input carried by the fibres that form the lateral olfactory tract (LOT) into the parahippocampal region of the in vitro isolated guinea pig preparation. Laminar analysis was performed on field potential depth profiles recorded with 16-channel silicon probes at different sites of the insular-parahippocampal cortex. The LOT input induced a large amplitude polysynaptic response in the lateral EC. Following appropriate LOT stimulation, a late response generated by the interposed activation of the hippocampus was observed in the medial EC. LOT stimulation did not induce any local response in area 36 of the perirhinal cortex (PRC), while a small amplitude potential with a delay similar to the lateral EC response was inconsistently observed in PRC area 35. No PRC potentials were observed following the responses evoked by LOT stimulation in either the lateral or the medial EC. These findings were substantiated by current source density analysis of PRC laminar profiles. To further verify the absence of EC-to-PRC field interactions after LOT stimulation, high-resolution optical imaging of neuronal activity was performed after perfusion of the isolated brain with the voltage-sensitive dye RH-795. The optical recordings confirmed that olfactory-induced activity in the EC does not induce massive PRC activation. The present findings suggest that the olfactory input into the parahippocampal region is confined to the entorhinal cortex. The results also imply that, as demonstrated for the PRC-to-EC pathway, the propagation of neuronal activity from the EC to the PRC is hindered, possibly by a powerful inhibitory control generated within the EC.

The aim of the study was the evaluation of the relationship between chemical fat analysis and some more rapid tests proposed to estimate steatorrhoea. Stool collections (72 h) were obtained on 32 occasions in 22 patients with cystic fibrosis and in seven healthy children. A very close relationship was found between faecal fat, as measured by standard chemical methods, and faecal energy (r = 0.95, P0.001). We conclude that the determination of faecal energy, easier to measure than faecal fat, can provide reliable information about the extent of steatorrhoea in cystic fibrosis.

Interictal spikes (ISs) are typically observed between seizures in focal epilepsies. Whether ISs are causally involved or represent protective elements in the transition toward an ictal discharge is an open question. Previous studies suggested that inhibition or disfacilitation occurs during the period elapsing between two ISs induced by local application of either bicuculline or penicillin in the piriform cortex of the in vitro isolated guinea pig brain preparation. We further investigated this issue by studying responses to afferent stimulation during the interspike period (6.3 +/- 2.5 s; mean +/- SD). Properly set stimulation intensity of the lateral olfactory tract resets ISs exclusively (and not before) 4-10 s (5.6 +/- 2.0 s; mean +/- SD) after a preceding spontaneous spike. This finding demonstrates the existence of a period of enhanced threshold to stimulus-evoked activation that coincides with the interspike interval in the absence of stimulation. Current source density analysis of depth laminar profiles demonstrated that both stimulus-evoked and spontaneous ISs were generated by the activation of an identical cortical circuit. Our study suggests that interictal spiking could play a protective role or at least provide an effective restraint against the onset of a focal ictal discharge.

The whole-cell patch-clamp technique was used to record Ca2+ currents in acutely dissociated neurons from layer II of guinea-pig piriform cortex (PC). Ba2+ (5 mM) was used as charge carrier. In a subpopulation of layer II cells ( approximately 22%) total Ba2+ currents (IBas) displayed a high degree (70%) of inactivation after 300 ms of steady depolarization. The application of L-, N- and P/Q-type Ca2+-channel blockers to these high-decay IBas left their fast inactivating component largely unaffected. The inactivation phase of the blocker-resistant, fast-decaying IBa thus isolated had a bi-exponential time course, with a fast time constant of approximately 20 ms and a slower time constant of approximately 100 ms at voltage levels positive to -10 mV. The voltage dependence of activation of the blocker-resistant, fast-decaying IBa was shifted by approximately 7-9 mV in the negative direction in comparison with those of other pharmacologically and/or kinetically different high-voltage-activated Ca2+ currents. We named this blocker-resistant, fast-decaying, intermediate-threshold current IRfi. The amplitude of IRfi decreased only slightly (by approximately 9%) when extracellular Ca2+ was substituted for Ba2+, in contrast with that of slowly decaying, high-voltage-activated currents, which was reduced by approximately 41% on average. Moreover, IRfi was substantially inhibited by low concentrations of Ni2+ (50 microM). We conclude that IRfi, because of its fast inactivation kinetics, intermediate threshold of activation and resistance to organic blockers, represents a definite, identifiable Ca2+ current different from classical high-voltage-activated currents and clearly distinguishable from classical IT. The striking similarity found between IRfi and Ca2+ currents resulting from heterologous expression of alpha1E-type channel subunits is discussed.

A peculiar, layer-segregated immunoreactive distribution of GABABR1a and GABABR1b receptor antibodies is present in the piriform cortex of adult rats. The GABABR1a antibody selectively marked the neuropile in layer Ia, where afferent olfactory fibres and intrinsic GABAergic (gamma-aminobutyric acid) axons terminate on the distal apical dendrites of pyramidal neurons. The GABABR1b antibody was detected in the soma and the large basal dendrites of layer II and III neurons. The pattern of distribution observed supports the hypothesis that (presynaptic) GABABR1a receptors in the superficial molecular layer modulate neurotransmitter release in a feedforward synaptic circuit, whereas GABABR1b (postsynaptic) receptors mediate feedback inhibitory potentials on principal cells.

Background: As previously reported, dual-energy x-ray absorptiometry provides reliable and accurate values for bone mineralization in piglets and infants, but overestimates fat content in small infants. The purpose of the current study was to determine an appropriate equation of correction for fat mass measurement and to establish reference values of body composition of preterm and term neonates. Methods: Fat mass and chemical whole-body fat content were evaluated by dual-energy x-ray absorptiometry in eight piglets with a body weight between 1408 and 5151 g. The results were combined with previous data obtained in 13 piglets, and two correction equations were determined according to fat mass content. Close to birth, 106 healthy appropriate-for-gestational-age preterm and term infants were scanned by dual-energy x-ray absorptiometry to determine bone mineral content, bone area, and fat mass. Fat mass content determined by dual-energy x-ray absorptiometry was corrected using the equations obtained in piglets after which lean body mass was recalculated. Results: Multivariate analysis showed that dual-energy x-ray absorptiometry body weight was the best predictor of bone mineral content (r 2 = 0.94), bone area (r 2 = 0.95), lean body mass (r 2 = 0.98), and fat mass (r 2 = 0.84). Gender was an additional significant independent variable for fat mass and lean body mass. Body weight related curves of percentiles for bone mineral content, bone area, fat mass, and lean body mass, were constructed. In vivo dual-energy x-ray absorptiometry values of fat mass and calcium content estimated from bone mineral content were in accordance with previously reported whole-body carcass reference values in preterm and term neonates. Conclusion: Normative data of dual-energy x-ray absorptiometry body composition for healthy preterm and term infants are provided and can therefore be used in research and in clinical practice.

The goal of feeding regimens for low birth weight (LBW) infants is to obtain a prompt postnatal resumption of growth to a rate approximating that seen during intrauterine growth and to follow after term a growth rate similar to that of breast-fed term infants (1). Human intrauterine and postnatal growth, and body composition, have therefore been studied extensively in order to obtain reference values (2–8). Among the various body compartments, bone mineralization and calcium retention have received considerable attention and sophisticated techniques have been developed in order to define the most appropriate diet for preterm and term infants.

Idiopathic generalized epilepsy is characterized by the spontaneous occurrence on the electroencephalogram of bilateral synchronous spike and wave discharges that involve the entire cortical mantle from the very onset. A central role in cortical synchronization is played by the thalamus, and in particular by the reticularis thalami nucleus, which is regarded as the pacemaker structure for the rhythmic cortical oscillations called spindle activity. Several studies have suggested that the network mechanisms which underlie spindle generation can also account for spike and wave discharges. Experimental investigations on genetic animal models of generalized epilepsy, in which seizures occur spontaneously in the absence of any inductive agent, confirmed that the thalamo-cortical system is involved in spike and wave discharge generation. According to these studies a genetically determined dysfunction in reticularis thalami neurons may alter the electroresponsiveness of the developing thalamo cortical system and cause a persistent state of abnormal excitation.

The morphological features of cerebral tissue in the isolated guinea-pig brain maintained in vitro by arterial perfusion are described. Light and electron microscopic anatysis of the thalamus, the somatosensory cortex and the limbic cortices (hippocampus, piriform and entorhinal cortices) was performed after different periods of incubation in vitro (1,7 and 12 h), in parallel with an electrophysiological study. The morphological analysis showed that neuronal elements retained their normal appearance at both cellular and subcellular level in the examined brain regions up to an incubation period of 12 h. Immunoreactivity for GABA was also preserved for up to 12 h of in vitro perfusion. Vasogenic edema and perivascular extracellular swelling appeared after 7 h, together with signs of progressive astrocytic deterioration. These findings show that normal electrophysiological recordings correlate with good anatomical preservation of the isolated guinea-pig brain preparation after prolonged times of arterial in vitro perfusion.

Introduction: An increased risk of infectious and allergic disease has been suggested for neonates born from caesarean delivery. The innate immunity play a crucial role in the host defence in neonatal age. The aim of this study is to evaluate the effects of delivery mode on innate immunity in newborn. Methods: Prospective, multicentre study involving newborns with birth weight (BW) > 2000 g and gestational age (GA) > 37 weeks. Serum levels of alpha- (HNP 1-3) and beta-defensins (hBD-2) were adopted as a markers of innate immune response. At birth, blood samples from neonatal cord vessels and from their mother peripheral vein were collected, and HPN 1-3 and hBD-2 were measured by commercially available ELISA kits. Data regarding pregnancy and perinatal period were also recorded. Results: Data from 66 newborns and their mother's were available. Levels of hBD2 were higher in newborn by spontaneous delivery (122.7 ± 4.6 pg/ml) than in those born by caesarian section (107.5 ± 5.5 pg/ml, p= 0.038). In the absence of labor maternal HNP 1-3 resulted significantly lower (245.3 ± 25.7 ng/ml) than in the presence of labor (594.6 ± 36.3 ng/ml, p=0.007). Conclusions: Caesarian delivery and absence of labor impair innate immunity in newborns. This may have important implications in the prevention of infectious and allergic disease early in the life.

Ranitidine Therapy Increases the Risk of Sepsis and Necrotizing Enterocolitis in Very Low Birthweight Infants: Prospective Multicenter Study