Subacute Posterior Inferior Cerebellar Artery Stroke Radiographically Mimicking Lhermitte-Duclos Disease.

Lhermitte-Duclos disease (LDD) is a rare cerebellar lesion characterized by a hamartomatous lesion of the cerebellum. Mainly diagnosed by MRI, the clinical presentation is usually made of neurological symptoms. Modern neuroimaging techniques such as MRI have led to accurate diagnosis of this disease in both its pre- and post-operative periods.

Adapting Clinical Practice of Thrombolysis for Acute Ischemic Stroke Beyond 4.5 Hours: A Review of the Literature.

Several clinical trials have demonstrated that advanced neuroimaging can select patients for recanalization therapy in an extended time window. The favorable functional outcomes and safety profile of these studies have led to the incorporation of neuroimaging in endovascular treatment guidelines, and most recently, also extended to decision making on thrombolysis. Two randomized clinical trials have demonstrated that patients who are not amenable to endovascular thrombectomy within 4.

Factors that Influence Door-to-Needle Administration for Acute Stroke Patients in the Emergency Department.

BACKGROUND: There is growing importance on discovering factors that delay time to intervention for acute ischemic stroke (AIS) patients, as rapid intervention is essential for better patient outcomes. The management of these patients involves a multidisciplinary effort and quality improvement initiatives to safely increase treatment with intravenous (IV) thrombolytic. The objective of this pilot study is to evaluate factors of acute stroke care in the emergency department (ED) and their impact on IV alteplase administration.

Musical hallucinations with a right frontotemporal stroke.

have been reported in association with psychiatric diseases, brain stem strokes, deafness, degenerative diseases, intoxications, pharmacologic agents, and epilepsy. We present a patient who in the absence of these disorders developed musical hallucinations from an infarction of the right hemisphere that primarily injured his right frontal and anterior temporal lobes. This report discusses some of the possible mechanisms for this patient's presentation.

Updates in the Management of Cryptogenic Stroke and Patent Foramen Ovale.

Background: Stroke is a common neurological disorder and may present with visual symptoms. A thorough workup is warranted to determine the underlying cause of stroke to optimize secondary prevention. Despite a full workup, a high-risk mechanism may not be identified.

Divergent unprotected peptide macrocyclisation by palladium-mediated cysteine arylation.

Macrocyclic peptides are important therapeutic candidates due to their improved physicochemical properties in comparison to their linear counterparts. Here we detail a method for a divergent macrocyclisation of unprotected peptides by crosslinking two cysteine residues with bis-palladium organometallic reagents. These synthetic intermediates are prepared in a single step from commercially available aryl bis-halides.

Adenovirus in Rural Côte D'Ivoire: High Diversity and Cross-Species Detection.

The Taï region in Western Côte d'Ivoire is characterized by extensive overlap of human and animal habitats. This could influence patterns of adenovirus transmission between humans and domestic animals. Fecal samples from humans and various domestic animals were tested for the presence of adenoviruses by PCR.

Decortication decreases paired-pulse facilitation in the neostriatal slice of the rat.

Paired-pulse facilitation, a form of short-term synaptic enhancement, occurs in the neostriatum. The present experiments were designed to determine the contributions of neostriatal afferents to the maintenance of this form of short-term facilitation. There are 3 major afferents to the neostriatum: the neocortex, the substantia nigra and the medial thalamus.

Norepinephrine modulates excitatory amino acid-induced responses in developing human and adult rat cerebral cortex.

These experiments were designed to assess the ability of norepinephrine and its beta-receptor agonist, isoproterenol, to modulate responses induced by activation of excitatory amino acid receptors in brain slices obtained from developing human cortex or adult rat cortex. Human cortical slices were obtained from children undergoing surgery for intractable epilepsy (9 months to 10 yr of age). For comparison, slices were also obtained from rats (2-3 months of age).

Neurophysiological, pharmacological and morphological properties of human caudate neurons recorded in vitro.

Tissue samples from the caudate nucleus were obtained from eight children (eight to 172 months of age) who underwent hemispherectomies for the relief of intractable seizures. Neurophysiological, pharmacological and morphological properties of caudate neurons were characterized by intracellular recordings in an in vitro slice preparation. These properties were compared with those of tissue obtained from animal studies.

Neuromodulatory actions of dopamine in the neostriatum are dependent upon the excitatory amino acid receptor subtypes activated.

In the mammalian neostriatum, dopamine modulates neuronal responses mediated by activation of excitatory amino acid receptors. The direction of this modulation varies with the specific subtype of excitatory amino acid receptor activated. Responses evoked by iontophoretic application of glutamate (Glu) and the non-N-methyl-D-aspartate (NMDA) agonists quisqualate and alpha-amino-3-hydroxy-5-methyl-4- isoxazolepropionic acid were significantly attenuated when dopamine was applied.

Evidence for enhanced synaptic excitation in transplanted neostriatal neurons.

Fetal neostriatal tissue was transplanted into either the neostriatum or substantia nigra of adult rats. One to 6 months after transplantation, coronal brain slices were taken through the rostrocaudal extent of the transplants and neurons were characterized electrophysiologically using an in vitro slice preparation. When compared to control neurons taken from intact adult neostriata, transplanted neostriatal neurons (TSNs) had higher input resistances and longer time constants.

Dye-coupling in human neocortical tissue resected from children with intractable epilepsy.

Interneuronal communication mediated by gap junctions has been proposed to have an important role in brain development and in the genesis of epilepsy. Indirect evidence for the existence and function of gap junctions has been obtained by studying dye-coupling, the transfer of the low-molecular-weight fluorescent dye Lucifer yellow (LY), among neurons. In the present study, the incidence of dye-coupling was assessed at different stages of human postnatal brain development.

Age-induced changes in electrophysiological responses of neostriatal neurons recorded in vitro.

The present studies were undertaken to determine whether the major electrophysiological characteristics of neostriatal neurons are altered during aging. The passive and active membrane properties of 130 neostriatal neurons obtained from young (three to five months, N = 65) and aged (24-26 months, N = 65) Fischer 344 rats were compared using an in vitro slice preparation. The results indicated that in a population of aged neostriatal neurons the majority of the electrophysiological changes that occurred resulted in decreases in cellular excitability.

Differential modulation by dopamine of responses evoked by excitatory amino acids in human cortex.

The responses of human neocortical neurons to iontophoretic application of excitatory amino acids and their modulation by dopamine (DA) were studied in vitro. Brain slices were obtained from children undergoing surgery for intractable epilepsy. Application of N-methyl-D-aspartate (NMDA) to the slices induced slow depolarizations accompanied by decreased input conductances and sustained action potentials in cortical neurons.

Enhanced responses to NMDA receptor activation in the developing cat caudate nucleus.

An in vitro slice preparation was used to assess the effects of N-methyl-D-aspartate (NMDA) receptor activation in the developing cat caudate nucleus. Removal of Mg2+ from the bathing medium, in the presence of 10 microM bicuculline, increased the amplitude and duration of the excitatory postsynaptic potential induced by local extracellular stimulation at all ages tested. In neurons younger than 35 days of age, removal of Mg2+ in the presence of bicuculline produced an increase in excitatory postsynaptic potential amplitude and duration as well as bursts of action potentials when local extracellular stimulation was applied.

Altered excitatory amino acid function and morphology of the cerebellum of the spastic Han-Wistar rat.

A mutant strain of Han-Wistar rat carries an autosomal recessive gene producing spastic paresis which is characterized by ataxia, tremor and hind limb rigidity. Brains of affected rats and unaffected littermate controls were transected at the mesencephalon into rostral and caudal portions (the caudal portion contained the cerebellum and brainstem). Poly(A)+ mRNA was isolated from pooled rostral or caudal portions and injected into Xenopus oocytes.

Iontophoretic application of NMDA produces different types of excitatory responses in developing human cortical and caudate neurons.

The effects of iontophoretically applied N-methyl-D-aspartate (NMDA) were assessed in human neocortical and caudate neurons. NMDA depolarized cell membranes, decreased input conductances and induced firing. The discharge patterns differed in the two areas studied.

Neurophysiological maturation of cat substantia nigra neurons: evidence from in vitro studies.

The membrane properties and synaptic physiology of developing cat substantia nigra (SN) neurons were studied in in vitro slice preparations. Stable intracellular recordings were obtained from 46 neurons in 20 kittens ranging in age from fetal day (F) 51 to postnatal day (P) 120. Only two of these properties changed with development.

Neurophysiological maturation of cat caudate neurons: evidence from in vitro studies.

The membrane properties and synaptic physiology of developing cat caudate (Cd) nucleus neurons were studied in in vitro slice preparations. Recordings were obtained from 98 cells in kittens from fetal day (F) 56 to postnatal day (P) 90. With increasing age, the following maturational changes occurred; resting membrane potentials became more negative, action potential rise times decreased, action potential amplitudes increased, and action potential durations and input resistances decreased.

Synaptic transmission in human neocortex removed for treatment of intractable epilepsy in children.

Synaptic transmission to pyramidal cells was studied in slices of neocortex resected from infants and children (n = 10, age 8 months to 13 years) undergoing surgical treatment for intractable epilepsy. Most specimens were from the least abnormal area of the resection. Stable intracellular recordings could be obtained for up to 8 hours.

Patterns of tachykinin expression and localization in developing feline neostriatum.

The development of tachykinins in the neostriatum was determined qualitatively in order to characterize the ontogeny of an early-forming neostriatal peptidergic system. Tachykinins were detected by immunohistochemistry in fetal, postnatal, and adult cats. Neostriatal cells and neurites expressed tachykinins as early as fetal age 30 and increased in frequency progressively with age.

Caudate neurons respond to excitatory and inhibitory amino acids in early postnatal periods in the cat.

This study was designed to determine whether caudate neurons would respond to microphoretic application of glutamate and gamma-aminobutyric acid (GABA) in early postnatal periods in the cat. Extracellular recordings were performed in 175 neurons in developing kittens and 114 neurons in adult cats. At the earliest ages tested (1-10 days), caudate cells were excited by microphoretic application of glutamate and were inhibited by application of GABA.

Connectivities of the striatal grafts in adult rat brain: a rich afference and scant striatonigral efference.

Previous reports from this laboratory have indicated that fetal rat striatal grafts have the major types of neuronal and glial components known to be involved in Huntington's chorea. In this study a number of major afferent and efferent innervations seen in normal striatum were examined in the striatal grafts and were compared with embryonic striatal afferents. First, using immunocytochemistry and histochemistry, the host serotonergic (5-HT), dopaminergic (DA, stained with anti-tyrosine hydroxylase (TH) antiserum), and acetylcholinesterase (AChE) fibers exhibited vigorous growth into the grafts implanted in neostriatum, lateral ventricle, globus pallidus or substantia nigra within a period of 6 and 10 weeks.