Smoking during pregnancy: a risk factor for peripheral neuropathy?

Studies dealing with the outcomes of developmental carbon monoxide (CO) exposure on myelination in rat offspring are reviewed. Prenatal CO exposure from gestational day 0 to gestational day 20 impairs myelin deposition around peripheral axons resulting in a significant hypomyelination in juvenile and adult rats. Myelin protein patterns analyzed by SDS-polyacrylamide gel electrophoresis and lipid patterns analyzed by the HPTLC method are not altered in both peripheral and central nervous systems of CO-exposed offspring. Interestingly, when sphingomyelin is extracted and purified, the derivatization by OPA reagent and analysis by reversed-phase HPLC reveal a significant increase in sphingosine levels in peripheral nervous system but not in central nervous system of CO-exposed rats. The above morphological and biochemical alterations are not accompanied by motor disabilities.     

Classification and diagnostic criteria for demyelinating diseases of the central nervous system: Where do we stand today?

The diagnosis of multiple sclerosis (MS) and other demyelinating diseases of the central nervous system is challenging, and although the currently available biological and imaging tools offer considerable support to physicians, these tools often fail to provide a simple and final answer at the time of a first event. Thus, sets of diagnostic criteria have been published and tested on patient cohorts, and are now used in clinical trials and in daily clinical practice. These criteria have evolved over time to take into account physicians’ and patients’ needs, along with emerging paraclinical tests. The different presentations of MS have given rise to the use of a common classification system to identify patient profiles and adapt care protocols accordingly. This article reviews the various classifications of the forms and diagnostic criteria of MS and related syndromes, including neuromyelitis optica (NMO)/NMO spectrum disorders (NMOSDs), acute disseminated (demyelinating) encephalomyelitis (ADEM) and chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS). Also discussed is their validity in the light of the currently available literature.     

Is migraine a disorder of the central nervous system?

The chicken and the egg problem is how, in Italian or in English, some time ago one would have referred to a question as the one to be approached here: “Is migraine a disorder of the central nervous system?” or of the peripheral nervous system? Till some time ago, even an honest basic scientist or clinician could almost equally sustain one or the other origin and find data that substantiate her/his opinion. Nowadays, however, our improved knowledge is pushing in the direction of the central nervous system, although many mechanisms remain unclear. The confusion originates from the important role played by multiple and important bidirectional interactions between the peripheral and the central nervous systems, i.e., the trigeminovascular system and the cerebral cortex. The problems are: Who starts first? Who is not working properly? It appears now that the answer to the question has to be probably searched in the delicate balance present in the central nervous system between excitatory and inhibitory circuits, their adaptation to chronic stimuli and, within these circuits, the balance of neurotransmitters, neuromodulators, transporters and ion channels that keeps them well functioning.     

Connexin: a potential novel target for protecting the central nervous system?

Connexin subunits are proteins that form gap junction channels, and play an important role in communication between adjacent cells. This review article discusses the function of connexins/hemichannels/gap junctions under physiological conditions, and summarizes the findings regarding the role of connexins/hemichannels/gap junctions in the physiological and pathological mechanisms underlying central nervous system diseases such as brain ischemia, traumatic brain and spinal cord injury, epilepsy, brain and spinal cord tumor, migraine, neuroautoimmune disease, Alzheimer’s disease, Parkinson’s disease, X-linked Charcot-Marie-Tooth disease, Pelizaeus-Merzbacher-like disease, spastic paraplegia and maxillofacial dysplasia. Connexins are considered to be a potential novel target for protecting the central nervous system.     

Vascular endothelial growth factor in central nervous system injuries - a vascular growth factor getting nervous?

Vascular Endothelial Growth Factor (VEGF) is recognized as a central factor in growth, survival and permeability of blood vessels in both physiological and pathological conditions. It is as such of importance for vascular responses in various central nervous system (CNS) disorders. Accumulating evidence suggest that VEGF may also act as a neuroprotective and neurotrophic factor supporting neuronal survival and neuronal regeneration. Findings of neuropilins as shared co-receptors between molecules with such seemingly different functions as the axon guidance molecules semaphorins and VEGF has further boosted the interest in the role of VEGF in neural tissue injury and repair mechanisms. Thus, VEGF most likely act in parallel or concurrent on cells in both the vascular and nervous system. The present review gives a summary of known or potential aspects of the VEGF system in the healthy and diseased nervous system. The potential benefits but also problems and pitfalls in intervening in the actions of such a multifunctional factor as VEGF in the disordered CNS are also covered.     

Sleep disorders: a risk factor for pseudotumor cerebri?

OBJECTIVE: To determine whether sleep-related breathing disorders are common in patients with idiopathic intracranial hypertension. MATERIALS AND METHODS: Medical records of 53 patients with idiopathic intracranial hypertension from a tertiary center neuroophthalmology practice were reviewed. Thirty-seven patients were identified who had a history of snoring, difficulty sleeping, or daytime somnolence. The data from polysomnograms were tabulated to determine the frequency of apneas, hypopneas, and arousals. RESULTS: Fourteen of 37 patients with idiopathic intracranial hypertension and symptoms of sleep disturbance underwent polysomnography. There were two men and 12 women varying in age from 24 to 58 years (mean, 39.4 +/- 11.9). These patients were obese with body mass indexes varying from 33.0 to 63.2 (mean, 46.0 +/- 9.5). A diagnosis of sleep apnea was made in six and upper airway resistance syndrome in seven patients. CONCLUSIONS: Sleep-related breathing problems were common in our patients with idiopathic intracranial hypertension. Obesity was common in these patients and may be playing a causative role in sleep apnea and idiopathic intracranial hypertension. It is suggested that idiopathic intracranial hypertension patients who have symptoms of sleep disturbance should be further evaluated for the presence of sleep-related breathing problems.     

A case of Fabry disease with central nervous system (CNS) demyelinating lesions: a double trouble?

We present the case of a 36-year-old woman affected with Fabry disease (FD), with neuroradiologic and laboratory tests suggestive of a coexistent inflammatory demyelinating disease. Since the age of 23, she presented recurrent neurologic deficits, such as right limb paresthesias, diplopia, and right leg weakness. Magnetic resonance imaging revealed multiple demyelinating lesions in periventricular areas, corpus callosum, and spinal cord. Cerebrospinal fluid analysis showed the presence of oligoclonal bands, while visual-evoked potentials were delayed with preserved morphology. FD is usually considered as a differential diagnosis of multiple sclerosis, but we think that the best explanation of all pathological features in this case is the coexistence of the two diseases.     

Mazindol: a risk factor for pulmonary arterial hypertension?

Mazindol is an imidazo-isoindole derivative, a tricyclic compound and a non-amphetamine central nervous system stimulant that blocks dopamine and norepinephrine reuptake. Mazindol was withdrawn from the US and European markets in 1999 for reasons unrelated to its efficacy or safety around a time when other anorexic drugs were found to be associated with the development of pulmonary arterial hypertension (PAH). Despite the use of mazindol for decades, reports of PAH due to mazindol intake have been extremely rare. Recent interest on mazindol has emerged for the treatment of narcolepsy and attention-deficit/hyperactivity disorder. Therefore, an updated understanding of the potential benefits and risks of mazindol in these patient populations is warranted.     

Expression pattern of neuregulin-1 type Ⅲ during the development of the peripheral nervous system

Neuregulin-1 type III is a key regulator in Schwann cell proliferation, committing to a myelinating fate and regulating myelin sheath thickness. However, the expression pattern of neuregulin-1 type III in the peripheral nervous system during developmental periods(such as the premyelinating stage, myelinating stage and postmyelinating stage) has rarely been studied. In this study, dorsal root ganglia were isolated from rats between postnatal day 1 and postnatal day 56. The expression pattern of neuregulin-1 type III in dorsal root ganglia neurons at various developmental stages were compared by quantitative real-time polymerase chain reaction, western blot assay and immunofluorescent staining. The expression of neuregulin-1 type III m RNA reached its peak at postnatal day 3 and then stabilized at a relative high expression level from postnatal day 3 to postnatal day 56. The expression of neuregulin-1 type III protein increased gradually from postnatal day 1, reached a peak at postnatal day 28, and then decreased at postnatal day 56. Immunofluorescent staining results showed a similar tendency to western blot assay results. Experimental findings indicate that the expression of neuregulin-1 type III in rat dorsal root ganglion was increased during the premyelinating(from postnatal day 2 to postnatal day 5) and myelinating stage(from postnatal day 5 to postnatal day 10), but remained at a high level in the postmyelinating stage(after postnatal day 10).     

Long-term diffusion impairment of cerebral white matter in a degenerative disease of the central and peripheral nervous system: reflection of chronic excitotoxicity?

The authors report an abnormal prolonged restricted magnetic resonance imaging (MRI) proton diffusion that persisted for more than 2 years in a 6.5-year-old boy with a progressive neurological disease characterized by developmental retardation, peripheral polyneuropathy, and bilateral optical nerve atrophy. The long-term restricted magnetic resonance imaging proton diffusion observed in diffusion-weighted magnetic resonance images indicates chronic metabolic tissue impairment in the affected white matter, whereas measurable lactate accumulation in proton magnetic resonance spectroscopy was absent, and no respiratory complex abnormality was found in muscle tissue. These findings are suggestive of a chronically disturbed regulation of energy supply triggering a "slow onset" excitotoxicity, causing chronic hypoxia and leading to slow cell death as has been postulated in certain neurodegenerative processes.     

Behavioural inhibition: is it a risk factor for anxiety?

Behavioural inhibition is a stable temperamental trait that is identifiable during infancy and toddlerhood and is characterized by fearful reactivity to novelty. Children identified as behaviourally inhibited have been shown to be at increased risk for developing anxiety disorders such as social phobia. The current review addresses the link between behavioural inhibition and the risk for developing anxiety disorders. Research suggests that this risk may be modulated by a number of extrinsic and intrinsic factors. Extrinsic factors include particular parental beliefs, parenting styles, and childrearing contexts. Intrinsic factors include executive function capacities such as attention bias, attention shifting, inhibitory control, and self-monitoring. In the present paper we review the contribution of these factors to the development of anxiety in behaviourally inhibited children.     

Behavioural inhibition: Is it a risk factor for anxiety?

Abstract

Behavioural inhibition is a stable temperamental trait that is identifiable during infancy and toddlerhood and is characterized by fearful reactivity to novelty. Children identified as behaviourally inhibited have been shown to be at increased risk for developing anxiety disorders such as social phobia. The current review addresses the link between behavioural inhibition and the risk for developing anxiety disorders. Research suggests that this risk may be modulated by a number of extrinsic and intrinsic factors. Extrinsic factors include particular parental beliefs, parenting styles, and childrearing contexts. Intrinsic factors include executive function capacities such as attention bias, attention shifting, inhibitory control, and self-monitoring. In the present paper we review the contribution of these factors to the development of anxiety in behaviourally inhibited children.