Interhemispheric coherence of EEG rhythms in children: Maturation and differentiation in corpus callosum dysgenesis

OBJECTIVES

To evaluate the evolution of interhemispheric coherences (ICo) in background and spindle frequency bands during childhood and use it to identify individuals with corpus callosum dysgenesis (CCd).

METHODS

A monocentric cohort of children aged from 0.25 to 15 years old, consisting of 13 children with CCd and 164 without, was analyzed. The ICo of background activity (ICOBckgrdA), sleep spindles (ICOspindles), and their sum (sICO) were calculated. The impact of age, gender, and CC status on the ICo was evaluated, and the sICO was used to discriminate children with or without CCd.

RESULTS

ICOBckgrdA, ICOspindles and sICO increased significantly with age without any effect of gender (p < 10-4), in both groups. The regression equations of the different ICo were stronger, with adjusted R2 values of 0.54, 0.35, and 0.57, respectively. The ICo was lower in children with CCd compared to those without CCd (p < 10-4 for all comparisons). The area under the precision recall curves for predicting CCd using sICO was 0.992 with 98.9 % sensitivity and 87.5 % specificity.

DISCUSSION

ICo of spindles and background activity evolve in parallel to brain maturation and depends on the integrity of the corpus callosum. sICO could be an effective diagnostic biomarker for screening children with interhemispheric dysfunction.

Apathy in depression: An arterial spin labeling perfusion MRI study

INTRODUCTION

Apathy, as defined as a deficit in goal-directed behaviors, is a critical clinical dimension in depression associated with chronic impairment. Little is known about its cerebral perfusion specificities in depression. To explore neurovascular mechanisms underpinning apathy in depression by pseudo-continuous arterial spin labeling (pCASL) magnetic resonance imaging (MRI).

METHODS

Perfusion imaging analysis was performed on 90 depressed patients included in a prospective study between November 2014 and February 2017. Imaging data included anatomical 3D T1-weighted and perfusion pCASL sequences. A multiple regression analysis relating the quantified cerebral blood flow (CBF) in different regions of interest defined from the FreeSurfer atlas, to the Apathy Evaluation Scale (AES) total score was conducted.

RESULTS

After confound adjustment (demographics, disease and clinical characteristics) and correction for multiple comparisons, we observed a strong negative relationship between the CBF in the left anterior cingulate cortex (ACC) and the AES score (standardized beta = -0.74, corrected p value = 0.0008).

CONCLUSION

Our results emphasized the left ACC as a key region involved in apathy severity in a population of depressed participants. Perfusion correlates of apathy in depression evidenced in this study may contribute to characterize different phenotypes of depression.

Inferring Biochemical Reactions and Metabolite Structures to Understand Metabolic Pathway Drift

Inferring genome-scale metabolic networks in emerging model organisms is challenged by incomplete biochemical knowledge and partial conservation of biochemical pathways during evolution. Therefore, specific bioinformatic tools are necessary to infer biochemical reactions and metabolic structures that can be checked experimentally. Using an integrative approach combining genomic and metabolomic data in the red algal model Chondrus crispus, we show that, even metabolic pathways considered as conserved, like sterols or mycosporine-like amino acid synthesis pathways, undergo substantial turnover. This phenomenon, here formally defined as "metabolic pathway drift," is consistent with findings from other areas of evolutionary biology, indicating that a given phenotype can be conserved even if the underlying molecular mechanisms are changing. We present a proof of concept with a methodological approach to formalize the logical reasoning necessary to infer reactions and molecular structures, abstracting molecular transformations based on previous biochemical knowledge.

Postural instability and gait disorders after subthalamic nucleus deep brain stimulation in Parkinson's disease: a PET study

INTRODUCTION

Patients with Parkinson's disease sometimes report postural instability and gait disorders (PIGD) after subthalamic nucleus deep brain stimulation (STN-DBS). Whether this is the direct consequence of DBS or the result of natural disease progression is still subject to debate.

OBJECTIVE

To compare changes in brain metabolism during STN-DBS between patients with and without PIGD after surgery.

METHODS

We extracted consecutive patients from a database where all Rennes Hospital patients undergoing STN-DBS are registered, with regular prospective updates of their clinical data. Patients were divided into two groups (PIGD and No PIGD) according to changes after surgery, as measured with a composite score based on the selected Unified Parkinson's Disease Rating Scale items. All patients underwent positron emission tomography with ¹⁸[F]-fluorodeoxyglucose 3 months before and after surgery. We ran an ANOVA with two factors (group: PIGD vs. No PIGD; and phase: preoperative vs. postoperative) on SPM8 to compare changes in brain metabolism between the two groups.

RESULTS

Participants were 56 patients, including 10 in the PIGD group. The two groups had similar baseline (i.e., before surgery) characteristics. We found two clusters of increased metabolism in the PIGD group relative to the No PIGD group: dorsal midbrain/pons, including locomotor mesencephalic region and reticular pontine formation, and right motor cerebellum.

CONCLUSION

We found different metabolic changes during DBS-STN among patients with PIGD, concerning brain regions that are already known to be involved in gait disorders in Parkinson's disease, suggesting that DBS is responsible for the appearance of PIGD.

Subthalamic deep brain stimulation influences complex emotional musical experience in Parkinson's disease

Subthalamic deep brain stimulation (STN DBS) is an effective treatment for reducing the motor symptoms of patients with Parkinson's disease (PD), but several side effects have been reported, concerning the processing of emotions. Music has been shown to evoke powerful emotional experiences - not only basic emotions, but also complex, so-called aesthetic experiences. The goal of the present study was therefore to investigate how STN DBS influences the experience of both basic and more complex musical emotions in patients with PD. In a three-group between-participants design, we compared healthy controls (HC), patients receiving STN DBS (PD-DBS), and patients who were candidates for STN DBS and receiving medication only (PD-MO) on their assessments of subjectively experienced musical emotions. Results showed that in general, the experience of musical emotions differed only marginally between the PD-MO, PD-DBS, and HC groups. Nonetheless, we were able to discern subtle but distinct effects of PD and STN DBS in the emotional responses. Happy music, for instance, seemed to induce a heightened experience of negative emotions (tension) in PD-MO patients. STN DBS appeared to normalize this particular effect, but increased nostalgic feelings - a rather complex affective experience - in response to the same emotional stimuli. This should not be taken as indicating a bias for nostalgia in the PD-DBS subgroup, as these patients found music inducing melancholy to be less nostalgic and more joyful than HC did. In conclusion, our study showed that music elicits slightly altered emotional experiences in patients with and without STN DBS. In particular, STN DBS seems to induce less distinct emotional responses, blurring the boundaries between complex musical emotions.

Bioaccumulation of metallic trace elements and organic pollutants in marine sponges from the South Brittany Coast, France

The purpose of this study was to compare the accumulation of metallic and organic pollutants in marine sponges with the oyster Crassostrea gigas used as sentinel species. The concentrations of 12 Metallic Trace Elements (MTEs), 16 Polycyclic Aromatic Hydrocarbons (PAHs), 7 PolyChlorinated Biphenyls (PCBs), and 3 organotin derivatives were measured in 7 marine sponges collected in the Etel River (South Brittany, France). Results indicated Al, Co, Cr, Fe, Pb, and Ti particularly accumulated in marine sponges such as Hymeniacidon perlevis and Raspailia ramosa at higher levels compared to oysters. At the opposite, Cu and Zn accumulated significantly at higher concentrations in oysters. Among PAHs analyzed, benzo(a)pyrene bioaccumulated in H. perlevis at levels up to 17-fold higher than in oysters. In contrast, PCBs bioaccumulated preferentially in oysters. Significant differences exist in the abilities of marine phyla and sponge species to accumulate organic and metallic pollutants however, among the few sponge species studied, H. perlevis showed impressive bioaccumulation properties. The use of this species as bioindicator and/or bioremediator near shellfish farming areas is also discussed.

[Peroneal nerve palsy in children: Uncommon diagnosis of a proximal tibiofibular synovial cyst]

Compression of the common peroneal nerve by synovial cysts of the tibiofibular joint is a rare disease. Two macroscopic forms may be encountered: extraneural cysts and intraneural cysts. In a review of the literature, we found only three pediatric cases of common peroneal nerve palsy due to extraneural cysts and about 60 cases reported in adults. Taking advantage of the clinical history of two children operated in our department for this disease, we describe this uncommon entity, which must be diagnosed and treated rapidly. Even in the presence of severe clinical and electrophysiological symptoms, a full clinical recovery is possible, as observed in these two children. However, follow-up is needed because recurrence is possible.

Monopolar-probe monitoring during spinal surgery with expandable prosthetic ribs

BACKGROUND

Intraoperative monitoring (IOM) has been proven to decrease the risk of neurological injury during scoliosis surgery. The vertical expandable prosthetic titanium rib (VEPTR) is a device that allows spinal growth. However, injuries to the spinal cord and brachial plexus have been reported after VEPTR implantation in 2 and 5% of patients, respectively. Simultaneous monitoring of these two structures requires the use of multiple time-consuming and complex methods that are ill-suited to the requirements of paediatric surgery, particularly when repeated VEPTR lengthening procedures are needed. We developed a monopolar stimulation method derived from Owen's monitoring technique. This method is easy to implement, requires only widely available equipment, and allows concomitant monitoring of the spinal cord and brachial plexus. The primary objective of this study was to assess the reliability of our technique for brachial plexus monitoring by comparing the stability of neurogenic mixed evoked potentials (NMEPs) at the upper and lower limbs.

HYPOTHESIS

We hypothesised that the coefficients of variation (CVs) of NMEPs were the same at the upper and lower limbs.

MATERIAL AND METHODS

Twelve VEPTR procedures performed in 6 patients between 1st January 2012 and 1st September 2014 were monitored using a monopolar stimulating probe. NMEPs were recorded simultaneously at the upper and lower limbs, at intervals of 150 s. The recording sites were the elbow over the ulnar nerve and the popliteal fossa near the sciatic nerve. Wilcoxon's test for paired data was used to compare CVs of the upper and lower limb NMEPs on the same side.

RESULTS

Mean CV of NMEP amplitude at the lower limbs was 16.34% on the right and 16.67% on the left; corresponding values for the upper limbs were 18.30 and 19.75%, respectively. Mean CVs of NMEP latencies at the lower limbs were 1.31% on the right and 1.19% on the left; corresponding values for the upper limbs were 1.96 and 1.73%. The risk of type I error for a significant difference between the upper and lower limbs was 0.5843 on the right and 0.7312 on the left for NMEP amplitudes and 0.7618 on the right and 0.4987 on the left for NMEP latencies.

CONCLUSION

Using an epidural active electrode and a sternal return electrode allows simultaneous stimulation of the cervical spinal cord and brachial plexus roots. The NMEPs thus obtained are as stable (reliable) at the upper limbs as at the lower limbs. This easy-to-implement method allows simultaneous monitoring of the upper and lower limbs. It seems well suited to VEPTR procedures.

LEVEL OF EVIDENCE

IV, retrospective single-centre non-randomised study.

Tele-transmission of EEG recordings

EEG recordings can be sent for remote interpretation. This article aims to define the tele-EEG procedures and technical guidelines. Tele-EEG is a complete medical act that needs to be carried out with the same quality requirements as a local one in terms of indications, formulation of the medical request and medical interpretation. It adheres to the same quality requirements for its human resources and materials. It must be part of a medical organization (technical and medical network) and follow all rules and guidelines of good medical practices. The financial model of this organization must include costs related to performing the EEG recording, operating and maintenance of the tele-EEG network and medical fees of the physician interpreting the EEG recording. Implementing this organization must be detailed in a convention between all parties involved: physicians, management of the healthcare structure, and the company providing the tele-EEG service. This convention will set rules for network operation and finance, and also the continuous training of all staff members. The tele-EEG system must respect all rules for safety and confidentiality, and ensure the traceability and storing of all requests and reports. Under these conditions, tele-EEG can optimize the use of human resources and competencies in its zone of utilization and enhance the organization of care management.

Subthalamic nucleus stimulation in Parkinson disease induces apathy: a PET study

OBJECTIVE

Apathy may be induced by subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson disease (PD). We therefore wished to test the hypothesis that apathy induced by STN-DBS correlates with changes in glucose metabolism, using (18)FDG-PET.

METHODS

Twelve patients with PD were assessed 3 months before (M-3) and 3 months after (M+3) STN-DBS with (18)FDG-PET and the Apathy Evaluation Scale.

RESULTS

Apathy had significantly worsened at M+3 after STN-DBS. Positive correlations were observed between this variation in apathy scores and changes in glucose metabolism, especially in the right frontal middle gyrus (Brodmann area [BA] 10) and right inferior frontal gyrus (BA 46 and BA 47). Negative correlations between the two were observed in the right posterior cingulate gyrus (BA 31) and left medial frontal lobe (BA 9).

CONCLUSION

These preliminary results confirm the role of the subthalamic nucleus in associative and limbic circuitry in humans and suggest that it is a key basal ganglia structure in motivation circuitry.

Subthalamic nucleus stimulation affects orbitofrontal cortex in facial emotion recognition: a PET study

Deep brain stimulation (DBS) of the bilateral subthalamic nucleus (STN) in Parkinson's disease is thought to produce adverse events such as emotional disorders, and in a recent study, we found fear recognition to be impaired as a result. These changes have been attributed to disturbance of the STN's limbic territory and would appear to confirm that the negative emotion recognition network passes through the STN. In addition, it is now widely acknowledged that damage to the orbitofrontal cortex (OFC), especially the right side, can result in impaired recognition of facial emotions (RFE). In this context, we hypothesized that this reduced recognition of fear is correlated with modifications in the cerebral glucose metabolism of the right OFC. The objective of the present study was first, to reinforce our previous results by demonstrating reduced fear recognition in our Parkinson's disease patient group following STN DBS and, second, to correlate these emotional performances with glucose metabolism using ¹⁸FDG-PET. The ¹⁸FDG-PET and RFE tasks were both performed by a cohort of 13 Parkinson's disease patients 3 months before and 3 months after surgery for STN DBS. As predicted, we observed a significant reduction in fear recognition following surgery and obtained a positive correlation between these neuropsychological results and changes in glucose metabolism, especially in the right OFC. These results confirm the role of the STN as a key basal ganglia structure in limbic circuits.

Hyrtiazepine, an azepino-indole-type alkaloid from the Red Sea marine sponge Hyrtios erectus

Biological and chemical investigations of the methanolic crude extract of the Red Sea marine sponge Hyrtios erectus led to the isolation of a novel azepino-indole-type alkaloid named hyrtiazepine (2) and 5-hydroxy-1H-indole-3-carboxylic acid methyl ester (3), together with the known metabolites hyrtiosulawesine (1), 5-hydroxyindole-3-carbaldehyde (4), hyrtiosin A (5), and hyrtiosin B (6). Their structures were elucidated on the basis of mass spectrometry and detailed 2D NMR spectroscopic data. Hyrtiosulawesine (1) displayed a significant antiphospholipase A2 activity with an IC50 value of 14 microM in a fluorometric assay using Crotalus adamanteus venom phospholipase A2.

Does subthalamic nucleus stimulation induce apathy in Parkinson's disease?

BACKGROUND

Subthalamic Nucleus Deep Brain Stimulation (STN-DBS) has been shown to significantly improve motor symptoms in advanced Parkinson's disease (PD). Only few studies, however, have focused on the non-motor effects of DBS.

METHODS

A consecutive series of 15 patients was assessed three months before (M-3), then three months (M3) and six months (M6) after surgery. Mean (+/- SD) age at surgery was 59.7 (7.6). Mean disease duration at surgery was 12.2 (2.8) years. The Mini International Neuropsychiatric Inventory was used to assess psychiatric disorders three months before surgery. Depression was evaluated using Montgomery and Asberg Rating Scale (MADRS). Anxiety was evaluated using the AMDP system (Association for Methodology and Documentation in Psychiatry). Apathy was particularly evaluated using the Apathy Evaluation Scale (AES) and the Starkstein Scale. All these scales were performed at every evaluation.

RESULTS

Apathy worsened at M3 and M6 after STN-DBS in comparison with the preoperative evaluation: the AES mean score was significantly impaired between the preoperative (38.4+/-7.1) and both the postoperative M3 (44.6+/-9.5, p = 0.003) and M6 scores (46.0+/-10.9, p = 0.013). Significant worsening of apathy was confirmed using the Starkstein scale. There was no evidence of depression: the mean MADRS score did not differ before surgery (9.1+/-7.4) and at both M3 (8.6+/-8.2) and M6 (9.9+/-7.7) after STN-DBS. The anxiety level did not change between preoperative (9.4+/-9.2) and both M3 (5.5+/-4.5) and M6 (6.6+/-4.6) postoperative states.

CONCLUSION

Although STN-DBS constitutes a therapeutic advance for severely disabled patients with Parkinson's disease, we should keep in mind that this surgical procedure may contribute to the inducing of apathy. Our observation raises the issue of the direct influence of STN- DBS on the limbic system by diffusion of stimulus to the medial limbic compartment of STN.

Novel polyhydroxysterols from the Red Sea marine sponge Lamellodysidea herbacea

Chemical investigation of the dichloromethane extract of the Red Sea marine sponge Lamellodysidea herbacea led to the isolation of four novel polyhydroxysteroids: cholesta-8-en-3beta,5alpha,6alpha,25-tetrol (1), cholesta-8(14)-en-3beta,5alpha,6alpha,25-tetrol (2), cholesta-8,24-dien-3beta,5alpha,6alpha-triol (3), and cholesta-8(14),24-dien-3beta,5alpha,6alpha-triol (4). Their structures were identified through 1D and 2D NMR studies. Relative stereochemistries were established by analysis of chemical shifts, coupling constants, and NOESY correlations. Compounds 3-4 showed antifungal activity against Candida tropicalis, with an inhibition diameter of 13 and 11 mm at 10 microg/disc, respectively.

Cytotoxic activity of methanol extracts from Basidiomycete mushrooms on murine cancer cell lines

Crude methanol extracts of 58 mushroom species were screened for their cytotoxic activities against two murine cancer cell lines, L1210 and 3LL, using the tetrazolium assay. A majority of extracts (74%) exhibited IC50 > 100 microg/ml against both cell lines. A most marked activity against one of the cell lines was noted for nine species (14% of the tested species). While Amanitales and Russulales tested were not found active, Polyporales and Boletales gave better results. Four species exhibited a significant cytotoxic activity (IC50 < or = 20 microg/ml) against at least one of the two murine cancer cell lines (Ganoderma lucidum, Meripilus giganteus, Suillus granulatus, S. luteus). The last one had never been investigated for its cytotoxic compounds before.

Bioactive flavonoids of Tanacetum parthenium revisited

Bio-guided fractionation of an extract from Tanacetum parthenium showing activity as mitotic blocker allowed the isolation and identification of santin 3, jaceidin 2 and centaureidin 1. The latter two closely related flavonols, which, to the best of our knowledge, are isolated here together for the first time, form a mixture difficult to resolve and which is probably the reason for the confusion in the literature regarding their occurrence. Centaureidin 1 had an IC50 of 1 microM while jaceidin 2 and santin 3 were 200 times less active.

[Heterotopic ossification in Guillain-Barré syndrome]

INTRODUCTION

Heterotopic ossification are frequent in central nervous disease, on the opposite just a few cases have been described in peripheral disorders.

PURPOSE

To describe three cases of Guillain-Barré syndrome complicated by heterotopic ossification.

METHODS

From the detailed case reports and a review of the literature.

RESULTS

The authors report three cases of heterotopic ossification in Guillain-Barré syndrome. Each of them had serious symptom and had to go in intensive care. Two of them had encephalopathy. A patient had compression of ulnar nerve as complication of heterotopic ossification. In all cases the consequence of the heterotopic ossifications lead to a great functional handicap.

DISCUSSION

Heterotopic ossification is a frequent complication in central neurologic lesions such spinal cord injury or brain injury. Just a few cases following peripheral nerve disorders have been reported. Serious neurologic deficit and encephalopathy may influence the apparition of heterotopic ossifications in patients suffering from Guillain-Barre syndrome. This possibility of complication must be known by the clinicians who should have a special attention to such patients.