Mechanical transduction by ion channels: A cautionary tale

Mechanical transduction by ion channels occurs in all cells. The physiological functions of these channels have just begun to be elaborated, but if we focus on the upper animal kingdom, these channels serve the common sensory services such as hearing and touch, provide the central nervous system with information on the force and position of muscles and joints, and they provide the autonomic system with information about the filling of hollow organs such as blood vessels. However, all cells of the body have mechanosensitive channels (MSCs), including red cells. Most of these channels are cation selective and are activated by bilayer tension. There are also K⁺ selective MSCs found commonly in neurons where they may be responsible for both general anesthesia and knockout punches in the boxing ring by hyperpolarizing neurons to reduce excitability. The cationic MSCs are typically inactive under normal mechanical stress, but open under pathologic stress. The channels are normally inactive because they are shielded from stress by the cytoskeleton. The cationic MSCs are specifically blocked by the externally applied peptide GsMtx4 (aka, AT-300). This is the first drug of its class and provides a new approach to many pathologies since it is nontoxic, non-immunogenic, stable in a biological environment and has a long pharmacokinetic lifetime. Pathologies involving excessive stress are common. They produce cardiac arrhythmias, contraction in stretched dystrophic muscle, xerocytotic and sickled red cells, etc. The channels seem to function primarily as “fire alarms”, providing feedback to the cytoskeleton that a region of the bilayer is under excessive tension and needs reinforcing. The eukaryotic forms of MSCs have only been cloned in recent years and few people have experience working with them. “Newbies” need to become aware of the technology, potential artifacts, and the fundamentals of mechanics. The most difficult problem in studying MSCs is that the actual stimulus, the force applied to the channel, is not known. We don’t have direct access to the channels themselves but only to larger regions of the membrane as seen in patches. Cortical forces are shared by the bilayer, the cytoskeleton and the extracellular matrix. How much of an applied stimulus reaches the channel is unknown. Furthermore, many of these channels exist in spatial domains where the forces within a domain are different from forces outside the domain, although we often hope they are proportional. This review is intended to be a guide for new investigators who want to study mechanosensitive ion channels.

Depression in adults with epilepsy: Relationship to psychobiological variables

AIM: To characterize the relationship between depression and epilepsy-related seizures, treatment, hormonal and biological variables.

METHODS: Included were 200 Egyptian adults (male = 100, female = 100) with epilepsy (mean age: 30.87 ± 7.88 years; duration of illness: 13.89 ± 7.64 years) and 100 healthy matched subjects for comparison. Psychiatric interview, Beck Depression Inventory (BDI-II) and Hamilton Anxiety Rating Scale (HAM-A) were used to assess depression and anxiety. Blood levels of free testosterone, sex hormone binding globulin, prolactin, free thyroxin and thyroid stimulating hormone, serotonin, noradrenaline and adrenaline neurotransmitters were measured to assess endocrine and biological states.

RESULTS: Patients had higher rates of depressive disorder (25.5% or 51/200), mostly intermixed with anxiety (47.06%), psychotic features (19.61%), aggression (40%) and suicide (55%). Compared to controls, higher scores on the BDI-II were observed with right-sided epileptic foci (P = 0.011), polytherapy (P = 0.001) and lack of control on antiepileptic drugs (AEDs) (P = 0.0001). Patients had lower levels of serotonin (P = 0.001) [marked with depression (P = 0.012)] and adrenaline (P = 0.0001), while noradrenaline was lower with temporal lobe epilepsy (P = 0.039), left-sided foci (P = 0.047) and lack of control on AEDs (P = 0.017). Negative correlations were observed between levels of serotonin and BDI-II (P = 0.048) and HAM-A (P = 0.009) scores, but not with AEDs dose or drug level.

CONCLUSION: Comorbid depressive disorder with epilepsy appears to be closely related to seizure type, focus, side, intractability to medications and neurotransmitter changes. Thus, optimizing seizure control and early recognition and management of depression is necessary to improve patients’ quality of life.

Neuritin: A therapeutic candidate for promoting axonal regeneration

Following injury, the axons of the mammalian central nervous system do not regenerate. Many studies have aimed at understanding the mechanisms that prevent axonal regeneration and at designing ways to overcome the obstacles preventing axonal regrowth. These studies have identified numerous proteins as promoters of axonal regeneration. In this minireviews, we focus on neuritin as a therapeutic candidate for promoting axonal regeneration. Neuritin was first identified as a neuronal-activity-inducible gene product in the rat brain. The overexpression of neuritin in neurons or the application of neuritin to neurons induces neuritogenesis, neurite arborization, and axonal elongation both in vitro and in vivo. These morphological changes are often observed during the first step of axonal regeneration. Indeed, neuritin expression increases during axonal regeneration in the peripheral nervous system (PNS). Conversely, in a mouse model of diabetes mellitus, neuritin expression decreases in the PNS, and this reduced expression may result in deficient axonal regeneration. Neuritin is induced in the hippocampal dentate gyrus after temporal lobe epilepsy or brain ischemia; however, in these conditions, neuritin induction may exacerbate brain dysfunction through mossy fiber sprouting. Together, these findings support the hypothesis that tightly controlled regulation of neuritin may be required for the treatment of each unique axonal pathology.

Variation in experimental autoimmune encephalomyelitis scores in a mouse model of multiple sclerosis

Multiple sclerosis (MS) is a common demyelinating central nervous system disease associated with progressive physical impairment. To study the mechanism underlying disease pathogenesis and develop potential treatments, experimental autoimmune encephalomyelitis (EAE) is often used as an animal model. EAE can be induced in various species by introducing specific antigens, which ultimately result in motor dysfunction. Although the severity of the paralysis is indicated using the EAE score, there is no standard scoring system for EAE signs, and there is variability between research groups with regard to the exact EAE scoring system utilized. Here, we describe the criteria used for EAE scoring systems in various laboratories and suggest combining EAE score with another quantitative index to evaluate paralysis, such as the traveled distance, with the goal of facilitating the study of the mechanisms and treatment of MS.

Rituximab in neuromyelitis optica: A review of literature

Neuromyelitis optica spectrum disorders, or neuromyelitis optica (NMO), is an autoimmune disease of the central nervous system that must be distinguished from multiple sclerosis. Therapeutic approaches to relapse prevention in NMO include immunosuppressants and monoclonal antibodies. Rituximab, a monoclonal antibody that targets CD20 antigen expressed on the surface of pre-B, mature B-lymphocytes and a small subset of T-lymphocytes, has been widely used for the treatment of NMO. In this review, we aim to summarize global experience with rituximab in NMO. We identified 13 observational studies that involved a total of 209 NMO patients treated with rituximab. Majority of rituximab-treated patients evidenced stabilization or improvements in their disability scores compared to pre-treatment period and 66% of patients remained relapse-free during treatment period. Monitoring rituximab treatment response with CD19+ or CD27+ cell counts appears to improve treatment outcomes. We offer clinical pointers on rituximab use for NMO based on the literature and authors’ experience, and pose questions that would need to be addressed in future studies.

Targeting remyelination treatment for multiple sclerosis

Since disability in multiple sclerosis (MS) is a product of neurodegeneration and deficient remyelination, the ability to enhance neuroregeneration and myelin regeneration in MS is an enticing goal for MS drug development. In particular, remyelination treatments could promote return of neurological function and also prevent further axonal loss and neurodegeneration in MS due to trophic effects of myelin. The study of remyelination has advanced dramatically in the last several years such that a number of pathways inhibiting remyelination have been discovered, including those involving LINGO-1, Notch-1, hyaluronan, retinoid X receptor, and wnt/ß-catenin. Other approaches such as high throughput drug screening for remyelination drugs have caught fire, with identification of dozens of known drugs with oligodendrocyte maturation stimulatory effects. Several drugs identified through screens and other mechanisms are in the process of being further evaluated for remyelination in MS and MS models. We discuss the potential molecular targets and the variety of mechanisms towards drug identification and development in remyelination for MS.

Anatomizing the “King of Neurosciences”

The human nucleus accumbens (NA), a major part of the ventral striatum, is the area of continuity between the putamen and head of the caudate nucleus. It consists of two parts, a shell laterally and a core medially. The first is mainly connected to the limbic system and the second to the extrapyramidal motor system. The NA, a major pleasure center of the human brain, acts as a limbic-motor interface and is involved in several cognitive, emotional and psychomotor functions. It has a modulating function in the amygdala-basal ganglia-prefrontal cortex circuit. It is considered as the neural interface between motivation and action. Further, it is a principal modulator of the reward circuits and supplies motor expression to emotional responses. Such a clinical significance could easily explain the intense work taking place in the respective field of basic research. Its exceptional clinical importance justifies the title of the “King of Neurosciences” for this nucleus. Purpose of this editorial is to review the “informational paths” left behind by the few researchers who tried to explore the architecture (gross anatomy) of this ‘kingdom’. The first anatomical study focused on this nucleus came from Neto et al. The most extensive study of the NA gross, imaging, stereotactic and neurosurgical anatomy so far, came from the research efforts of Mavridis et al.

Medicine in the future - with subspecialists in medullary neurology and brain dentistry

The solitary tract nucleus of the medulla with its limited watershed vascular capacity may occasionally be the focus of transient ischemia caused by the increased metabolic demands associated with frequent and intense neuronal stimulation from other organs and other parts of the brain. Case reports have suggested that these ischemic changes may sometimes result in the initiation of intense autonomic discharges, which can occasionally be fatal. Therapeutic interventions for the medulla oblongata are hampered by its limited accessibility. Systemically administered pharmaceuticals may have some usefulness in future years. Previous experience with vagus nerve stimulation in the treatment of epilepsy suggests that it may have some usefulness in stabilizing medullary autonomic discharges. Computerized electronic stimulation of other cranial nerves may be helpful as well, especially the chorda tympani nerve, and may be most easily accomplished from implanted dental appliances, especially molar modules, transmitting signals via secondary transmitters procedurally placed on cranial nerves. Future technology may enable wireless signaling from the implanted dental appliance to the secondary transmitter placed at the nerve site. By the year 2050 subspecialists in medullary neurology and brain dentistry may use computerized electronic stimulation of cranial nerves to prevent sudden unexpected death and treat “chest pain from the brain”.

Aquaporin-4 and spinal cord injury

Edema formation is a major problem following traumatic spinal cord injury (SCI) that acts to exacerbate secondary damage. Severity of edema correlates with reduced neurological outcome in human patients. To date, there are no effective treatments to directly resolve edema within the spinal cord. The aquaporin-4 (AQP4) water channel is found on membranes of astrocytic endfeet in direct contact with blood vessels, the glia limitans in contact with the cerebrospinal fluid and ependyma around the central canal. Being so locally expressed at the interface between fluid and tissue allow AQP4 channels to play an important role in the bidirectional regulation of water homeostasis under normal conditions and following trauma. With the need to better understand the pathophysiology underlying the devastating cellular events in SCI, animal models have become an integral part of exploration. Inevitably, several injury models have been developed (contusion, compression, transection) resulting in difficult interpretation between studies with conflicting results. This is true in the case of understanding the role of AQP4 in the progression and resolution of edema following SCI, whose role is still not completely understood and is highly dependent on the type of edema present (vasogenic vs cytotoxic). Here, we discuss regulation of AQP4 in varying injury models and the effects of potential therapeutic interventions on expression, edema formation and functional recovery. Better understanding of the precise role of AQP4 following a wide range of injuries will help to understand optimal treatment timing following human SCI for prime therapeutic benefit and enhanced neurological outcome.

Relevance of long QT syndrome in clinical neurology

Long QT syndrome (LQTS) is a cardiac conduction disorder that predisposes patients at potentially fatal cardiac events. Inherited conditions and acquired factors contribute to LQTS. A number of frequently prescribed CNS-active drugs prolong the QT interval. The clinical neurologist may encounter LQTS when initiating a pharmacotherapy or when increasing the dosage of drugs. The clinical neurologist may also encounter LQTS during the diagnostic work-up of patients with unexplained loss of consciousness, because LQTS may present as convulsive syncope. Some studies report an association of LQTS and stroke. Awareness of LQTS may help to recognize and prevent potentially fatal cardiac events associated with LQTS. This concise article highlights the clinically most relevant aspects of LQTS in the field of neurology.

Brachial arteries sympathetic innervation: A contribution to anatomical knowledge

BACKGROUND

The sympathetic nervous system makes medium and large peripheral arteries smaller to slow the blood flowing through them.

AIM

To observe brachial artery sympathetic innervation.

METHODS

We developed a neurophysiological autonomous test that measured the effects of peripheral sympathetic fibres on peripheral arteries. Our specific objective was to find the sympathetic innervation of the brachial artery. To accomplish this purpose, the brachial artery baseline diameter and flow rate were measured in the right arm of the patients. Afterwards, electrical stimulus was applied to the medial nerve for 5 s. Through electrical sympathetic activation, the vessel diameter and overall flow rate will decrease. After 7 d, a similar experiment was repeated using the ulnar nerve.

RESULTS

The differences in diameter and flow rate of the brachial artery in response to median and ulnar nerve activation were compared. In the total group, no significant difference in diameter was seen between medial and ulnar nerve stimulation (P = 0.648). The difference in absolute slowdown of flow rate between median nerve stimulation and ulnar nerve stimulation was not statistically significant for the entire group (P = 0.733).

CONCLUSION

As a target organ, the brachial artery receives an equal amount of sympathetic innervation from the median and the ulnar nerves.

Time windows for postnatal changes in morphology and membrane excitability of genioglossal and oculomotor motoneurons

Time windows for postnatal changes in morphology and membrane excitability of genioglossal (GG) and oculomotor (OCM) motoneurons (MNs) are yet to be fully described. Analysis of data on brain slices in vitro of the 2 populations of MNs point to a well-defined developmental program that progresses with common age-related changes characterized by: (1) increase of dendritic surface along with length and reshaping of dendritic tree complexity; (2) disappearance of gap junctions early in development; (3) decrease of membrane passive properties, such as input resistance and time constant, together with an increase in the number of cells displaying sag, and modifications in rheobase; (4) action potential shortening and afterhyperpolarization; and (5) an increase in gain and maximum firing frequency. These modifications take place at different time windows for each motoneuronal population. In GG MNs, active membrane properties change mainly during the first postnatal week, passive membrane properties in the second week, and dendritic increasing length and size in the third week of development. In OCM MNs, changes in passive membrane properties and growth of dendritic size take place during the first postnatal week, while active membrane properties and rheobase change during the second and third weeks of development. The sequential order of changes is inverted between active and passive membrane properties, and growth in size does not temporally coincide for both motoneuron populations. These findings are discussed on the basis of environmental cues related to maturation of the respiratory and OCM systems.

Advances in the molecular diagnosis of Charcot-Marie-Tooth disease

Charcot-Marie-Tooth (CMT) disease or hereditary motor and sensory neuropathy is the most common inherited neuromuscular disorder affecting at least 1 in 2500. CMT disease is pathologically and genetically heterogeneous and is characterized by a variable age of onset, slowly progressive weakness and muscle atrophy, starting in the lower limbs and subsequently affecting the upper extremities. Symptoms are usually slowly progressive, especially for the classic and late-onset phenotypes, but can be rather severe in early-onset forms. CMT is grouped into demyelinating, axonal and intermediate forms, based on electrophysiological and pathological findings. The demyelinating types are characterized by severely reduced motor nerve conduction velocities (MNCVs) and mainly by myelin abnormalities. The axonal types are characterized by normal or slightly reduced MNCVs and mainly axonal abnormalities. The intermediate types are characterized by MNCVs between 25 m/s and 45 m/s and they have features of both demyelination and axonopathy. Inheritance can be autosomal dominant, X-linked, or autosomal recessive. Mutations in more than 30 genes have been associated with the different forms of CMT, leading to major advancements in molecular diagnostics of the disease, as well as in the understanding of pathogenetic mechanisms. This editorial aims to provide an account that is practicable and efficient on the current molecular diagnostic procedures for CMT, in correlation with the clinical, pathological and electrophysiological findings. The most frequent causative mutations of CMT will also be outlined.

Nucleus accumbens stereotactic surgery: Achieving accuracy through area M

The nucleus accumbens (NA), a major pleasure center of the human brain, is a limbic-motor interface involved in several neurological and psychiatric disorders. During the last decade, this nucleus is also a deep brain stimulation target for selected patients. Purpose of this paper is to comment on the article entitled “Stereotactic anatomy of the human nucleus accumbens: from applied mathematics to microsurgical accuracy” which was recently published in “Surgical and Radiologic Anatomy” and is one of the latest articles on NA anatomy and surgery. The described results included a probability-based guide for in vivo (side-depended) stereotactic localization of the human NA and a standard for the NA, specific stereotactic zone of the human brain (which can be used in combination for an accurate stereotactic NA targeting). Furthermore, two specific stereotactically standard NA areas were found which could be used as abundant stereotactic guides for targeting of the anterior limb of the internal capsule, with electrode’s contact 0 (lowest) placed in the vicinity of the NA. However, the most important finding of this paper was standard area M (Mavridis’ area), which is the most reliable stereotactically standard area of the human NA, regardless of side or gender, useful for highly accurate stereotactic NA targeting.

Clinical consequences of centipede bite: Is it neurotoxic?

The primary purpose of this article was to review the current literature regarding the clinical consequences of centipede envenomation in humans, in order to determine whether the bite of these arthropods is neurotoxic to humans or not. A thorough search of the literature regarding the clinical consequences of centipede bites in humans was applied, with great respect to neurological symptoms potentially caused by such bites. Centipede bite commonly causes only local reactions, which usually resolve within a few days without sequelae. The patients in the majority of centipede envenomations describe a painful but benign syndrome. However, mild constitutional symptoms are relatively frequent. Remarkably, centipedes can rarely cause severe systematic reactions such as anaphylaxis or even hypotension and myocardial ischemia. Factors such as patient age, comorbidity, anatomic site of envenomation, and size/species of centipede should be considered when evaluating a centipede envenomation victim. According to the current literature, the centipede bite does not seem to be neurotoxic to humans. However, it commonly causes symptoms mediated by the nervous system. These include local and generalized symptoms, with the first dominated by sensory disturbances and the second by non-specific symptoms such as headache, anxiety and presyncope. Based on our results, the answer to our study’s question is negative. The centipede bite is not neurotoxic to humans. However, it commonly causes symptoms mediated by the nervous system, which include primarily local pain and sensory disturbances, as well as generalized non-specific symptoms such as headache, anxiety and vagotonia.

Molecular pathogenesis of glioblastoma multiforme: Nuances, obstacles, and implications for treatment

Glioblastoma multiforme (GBM), the literal apogee on the hierarchy of malignant brain tumors, remains one of the greatest therapeutic challenges in oncology and medicine. Historically this may be contextualized in the fact that the medical and scientific communities have had a very elementary understanding of its intricate and complex pathophysiology. The last 10-15 years have yielded a number of studies that have elucidated much of the molecular and genetic complexities of GBM that underlie its pathogenesis. Excitingly, some of these discovered genetic mutations and molecular profiles in GBM have demonstrated value in prognostication and utility in predicting response to treatment. Despite this, however, treatment options for patients have remained somewhat limited. These treatment options are expected to expand with the availability of new data and with the transition of novel treatment modalities from animal to human studies. This paper will have a threefold objective: provide an overview of the traditional paradigm in understanding and treating GBM, describe recent discoveries in the molecular pathogenesis of GBM against this historical backdrop, and acquaint the reader with new treatment modalities that hold significant therapeutic potential for patients.

Treatment with botulinum toxin: An update

Botulinum neurotoxin (BoNT) is a potent toxin produced by the anaerobic bacterium clostridium botulinum. It causes flaccid, long-lasting, local and reversible paralysis. In addition, BoNT inhibits the secretion of the exocrine glands and could have properties in the control of pain. Thus, BoNT is useful in the treatment of many neuromuscular conditions where an increase of muscle tone is associated with the pathogenic mechanism. Furthermore, BoNT is recommended in the treatment of some hypersecretion disorders of the exocrine gland and could play a role in the treatment of migraine and other chronic pain conditions. In the BoNT therapy adverse effects are usually mild and reversible. However, repeated injections of BoNT can lead to the development of neutralizing antibodies that can subsequently inhibit the biological activity of the toxin. In this sense, many factors can influence the immunogenicity of the BoNT, such as product-related factors, the dose of BoNT used, the frequency of injection and the previous exposure to the toxin. In this review, we are going to discuss the current clinical applications of BoNT with a special focus on evidence, doses, injection technique and adverse effects for those applications more frequently used in neurology, namely spasticity, blepharospasm, hemifacial spasm, cervical dystonia and other focal dystonias, as well as chronic migraine, tremor, sialorrhea, facial palsy, neurogenic bladder and many other neurological condition.

Secondary prevention of ischaemic stroke

In spite of a documented reduction in incidence in high-income countries over the last decades, stroke is still a leading cause of death and disability worldwide. With the ageing of the population stroke-related economic burden is expected to increase, because of residual disability and its complications, such as cognitive impairment, high risk of falls and fractures, depression and epilepsy. Furthermore, because of the substantial rate of early and long-term vascular recurrences after the first event, secondary prevention after cerebral ischaemia is a crucial issue. This is even more important after minor stroke and transient ischaemic attack (TIA), in order to reduce the risk of potentially more severe and disabling events. To accomplish this aim, acute long-term medical and surgical treatments as well as lifestyle modifications are strongly recommended. However, apart from the well-established indications to thrombolysis, studies in acute phase after a first stroke or TIA are scarce and evidence is lacking. More trials are available for long-term secondary prevention with different classes of drugs, including antithrombotic medications for ischaemic events of arterial and cardiac origin, especially related to atrial fibrillation (antiplatelets and anticoagulants, respectively), lipid lowering agents (mainly statins), blood pressure lowering drugs, surgical and endovascular revascularization procedures.

Disciplined sleep for healthy living: Role of noradrenaline

Sleep is essential for maintaining normal physiological processes. It has been broadly divided into rapid eye movement sleep (REMS) and non-REMS (NREMS); one spends the least amount of time in REMS. Sleep (both NREMS and REMS) disturbance is associated with most altered states, disorders and pathological conditions. It is affected by factors within the body as well as the environment, which ultimately modulate lifestyle. Noradrenaline (NA) is one of the key molecules whose level increases upon sleep-loss, REMS-loss in particular and it induces several REMS-loss associated effects and symptoms. The locus coeruleus (LC)-NAergic neurons are primarily responsible for providing NA throughout the brain. As those neurons project to and receive inputs from across the brain, they are modulated by lifestyle changes, which include changes within the body as well as in the environment. We have reviewed the literature showing how various inputs from outside and within the body integrate at the LC neuronal level to modulate sleep (NREMS and REMS) and vice versa. We propose that these changes modulate NA levels in the brain, which in turn is responsible for acute as well as chronic psycho-somatic disorders and pathological conditions.

Periodontal surgery in a stage II Parkinson’s disease patient: Report of a case with special considerations

Parkinson’s disease (PD) is an idiopathic progressive neurological disorder characterised by resting tremor, restrictions in mobility and muscular rigidity that can lead to problems in maintaining oral health. Here we report a case where crown lengthening surgeries were successfully performed in a PD patient for complete oral rehabilitation. Certain special considerations that are required before and during periodontal surgery in such patients are also elucidated. Often dentists and PD patients are reluctant to embark on complex dental procedures resulting in a compromised outcome. However, early intervention along with proper education and motivation of these patients can aid in achieving satisfactory results.

Predictors of future stroke in adults 60-64 years living in the community

AIM: To investigate predictors of incident stroke in a large epidemiological sample of cognitively healthy individuals in their early 60’s.

METHODS: Cardiovascular (systolic and diastolic blood pressure, hypertension status and medication, body mass index, lung forced vital capacity), lifestyle (alcohol intake, smoking, physical activity), mental health (anxiety and depression status, medication and symptomatology), cognition (executive function, processing speed, working memory, sensorimotor skills), and personality measures (behavioural inhibition and activation, positive and negative affect, neuroticism, psychoticism, extraversion) were investigated as predictors of incident stroke in 1774 participants from the Personality and Total Health Through Life Project over an 8-year follow-up. Logistic regression analyses controlled for age, gender, and education were conducted in the whole cohort as well as in case-control sub-analyses including precisely matched controls to identify factors associated with stroke incidence.

RESULTS: The cohort selected had a mean age of 62.5 years (SD = 1.5) and was 48.6% female with an average of 14.1 years of education (SD = 2.6). When 28 individuals with incident stroke were compared to 1746 cognitively healthy individuals in multivariate logistic regression analyses the only significant predictors of stroke across the five domains considered (cardiovascular, lifestyle, mental health, cognition, personality) and after controlling for gender, age, and education were systolic blood pressure (per unit above 140 mmHg: OR = 1.04, 95%CI: 1.01-1.07, P = 0.002), smoking (trend OR = 2.28, 95%CI: 0.99-5.24, P = 0.052), and sensorimotor skills (purdue pegboard: OR = 0.80, 95%CI: 0.62-0.96, P = 0.037). Similarly, in matched-control analyses significant group differences were found for systolic blood pressure (P = 0.001), smoking (P = 0.036), and sensorimotor skills (P = 0.028).

CONCLUSION: Identified predictors of incident stroke in community-living individuals included high systolic blood pressure and smoking - but also, sensorimotor performance, a measure which has not yet been reported in the literature.

Pure motor stroke as the most frequent lacunar syndrome: A clinical update

Pure motor stroke (PMS), also known as pure motor hemiparesis, is the most common of any lacunar form (between one half and two thirds of cases, depending on the series). In an acute stroke registry, 733 patients presented a lacunar infarct and PMS accounted for 12.7% (n = 342) of all first-ever stroke patients and for 48% of all lacunar syndromes. The posterior limb of the internal capsule, corona radiata, and pons are the most frequent brain topographies. Infarcts in the mesencephalus or medullary pyramid have been exceptionally reported. This present update is focused on the clinical evidence and mechanisms underlying the relationship between PMS and different stroke etiologies.

Alcohol intolerance and myalgic encephalomyelitis/chronic fatigue syndrome

BACKGROUND

The literature is mixed about the occurrence of alcohol intolerance among patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Surveys that asked respondents with ME/CFS whether they experienced alcohol intolerance within a recent time frame might produce inaccurate results because respondents may indicate that the symptom was not present if they avoid alcohol due to alcohol intolerance.

AIM

To overcome this methodologic problem, participants in the current study were asked whether they have avoided alcohol in the past 6 mo, and if they had, how severe their alcohol intolerance would be if they were to drink alcohol.

METHODS

The instrument used was a validated scale called the DePaul symptom questionnaire. Independent t-tests were performed among the alcohol intolerant or not alcohol intolerant group. The alcohol intolerant group had 208 participants, and the not alcohol intolerant group had 96 participants.

RESULTS

Using specially designed questions to properly identify those with alcohol intolerance, those who experienced alcohol intolerance vs those who did not experience alcohol intolerance experienced more frequent/severe symptoms and domains. In addition, using a multiple regression analysis, the orthostatic intolerance symptom domain was related to alcohol intolerance.

CONCLUSION

The findings from the current study indicated that those with ME/CFS are more likely to experience alcohol intolerance. In addition, those with this symptom have more overall symptoms than those without alcohol intolerance.

Resolution of idiopathic intracranial hypertension after sustained lowering of cerebrospinal fluid pressure

Idiopathic intracranial hypertension (IIH) is a syndrome of headache due to raised intracranial pressure (ICP) where the cerebrospinal fluid (CSF) is normal and there is no alternative pathology on imaging. The aetiology is unknown. This review questions many of the prevailing views regarding aetiology and treatment of IIH. It explores the concept that there is a vicious cycle of fluctuating raised ICP leading to secondary compression of the transverse sinuses and further elevation of ICP. It also raises the question as to whether this vicious cycle could be relieved by prolonged drainage of CSF as seen in Lumbar puncture induced low-pressure headache or alternatively a lumbar drain.