Contribution of the neuropsychological assessment in concussion

INTRODUCTION

The neuropsychological assessment is a cornerstone in the care management of concussion or mild traumatic injury.

OBJECTIVE

To present the different stages of an exhaustive neuropsychological assessment exploring cognitive and behavioral domains.

METHOD

Description of the value of the main tests available for behavioral and cognitive assessment. The choice of tests is based on the clinical experience and expertise of the authors.

RESULTS

Questionnaires are mainly used to explore the behavioral sequelae (depression, anxiety or fatigue) and the impact of these potential difficulties in daily life. Four cognitive abilities could be impaired by concussion: attention, memory, visuospatial functions and executive functions. These abilities could be explored with "paper and pencil" tests or with computerized test batteries. While cognitive sequelae in the context of a moderate or a severe traumatic brain injury are consolidated, in the context of concussion, neuropsychological sequelae tend to resolve in a short time. As a consequence, several neuropsychological assessments could be conducting in a short period involving some methodological considerations. Moreover, as concussion could be reported in a Whiplash injury from a car crash with forensic consequences, it is crucial to propose tests to be sure that the weak performance obtained into the neuropsychological assessment is not explained by poor effort and/or malingering.

DISCUSSION/CONCLUSION

This article revises these aspects of a neuropsychological assessment in the specific context of concussion.

JS1.4 Neurological follow-up of neurotoxicity after CAR T cell therapy in lymphoma patients: A French neurological multi-center survey

BACKGROUND

Chimeric antigen receptor-modified T (CAR T) cell therapy is a highly promising treatment for haematological malignancies but is frequently associated with cytokine-release syndrome (CRS) and neurotoxicity. The physiopathological mechanisms of neurological complications and their links with CRS remain largely unknown. The aims of this study are: a) to follow-up longitudinally patients treated with CAR-T cell therapy; b) to exhaustively identify neurological signs and symptoms and; c) to describe their occurrence over time.

MATERIAL AND METHODS

Since September 2018, all patients treated with CD19-targeted CAR T cell therapy for relapsing lymphoma were systematically followed-up and monitored for signs of neurotoxicity by a neurologist. Five different centres (Paris-Saint-Louis, Nantes, Lyon, Montpellier, and Rennes) participated in this study.

RESULTS

As of April 1st 2019, 57 patients, mean age 49 years (range from 22 to 72 years, median age 50 years), 22 females / 35 males, all treated for lymphoma, were included in this study Neurotoxicity, defined as the presence of at least one neurological sign or symptoms appearing after treatment infusion, was present in 33 % of patients. The median time to onset was 7.5 days after infusion with a median duration of symptoms of 5 days. Neurological symptoms were: Encephalopathy (52%), cerebellar syndrome (26%), aphasia (15%), agraphia (15%), executive syndrome (10%), myoclonus (10%), dysarthria (10%), meningismus (5%), transverse myelitis (5%), seizure (5%), neuralgia (5%), and dysesthesia (5%). The severity grade of neurotoxicity was grade 4: 2 patients, Grade 3: 7 patients, grade 2: 5 patients and grade 1: 5 patients (CTCAE grading). CRS was observed in 75% of patients. All patients who developed neurological disorders also had CRS (grade 1: 68%, grade 2: 10%, grade 3: 15%, grade 4: 5%) that preceded neurotoxicity. As the study is still ongoing, updated results will be presented at the EANO meeting.

CONCLUSION

Neurotoxicity associated with CAR-T therapies occurs in one third of patients. This high frequency underlines the need: 1 - to neurologically assess all patients before and repeatedly after therapy infusions; 2 - to provide guidelines for neurological assessment and relevant investigations to improve early recognition of neurotoxicity and its management

P14.31 CMV reactivation in a cohort of newly-diagnosed glioblastoma patients treated with temozolomide chemoradiotherapy. A single center analysis

BACKGROUND

The Cytomegalovirus (CMV) is a ubiquitous herpes virus which infects 60–80 % of the population in Europe. Although the CMV usually remains latent, reactivation can occur in the context of an immunodepression, such as low CD4-lymphocyte levels in HIV patients. Glioblastoma (GBM) patients frequently show lymphopenia, which is related to both the immunosuppressive nature of the tumor and to the treatment with concomitant temozolomide (TMZ) and radiotherapy (RT). Surprisingly, the incidence of CMV reactivation in GBM patients has not been clearly studied so far. We report here our experience on CMV reactivation in a cohort of newly-diagnosed GBM patients, treated with RT and TMZ. We assessed the incidence of CMV reactivation in these patients and tried to identify risk factors for such reactivation.

MATERIAL AND METHODS

All consecutive patients with histologically confirmed malignant GBM recommended for temozolomide chemoradiotherapy in our institution from October 2013 to December 2015 were reviewed. In all patients, sex, age, Karnofsky performance status (KPS), lymphocyte level, serological CMV status and steroid dosages were recorded at the onset, and one month after completion of the concomitant radio-chemotherapy regimen. A CMV reactivation was defined by a detection of CMV DNA > 1000 copies/ml in the patient’s serum.

RESULTS

103 patients meeting the analysis criteria were reviewed. Within these 103 patients, 34 patients (33%) had initial negative serology for CMV, and none of them developed a seroconversion after treatment with concomitant RT + TMZ. Among patients with positive IgG (n=69), 16 patients (23%) developed a positive viremia at one point during treatment with concomitant RT + TMZ. Age (>60 years), lymphocyte count before RT (<1500/mm3) and use of steroids were correlated with CMV reactivation (p<0.05 in univariate analysis). A positive CMV viremia during RT+TMZ did not impact the progression free survival (PFS) but was associated with a shorter overall survival (OS) when compared to the others patients (median: 12 months vs 15 months; p=0.04). No clinical symptoms suggestive of CMV infection were reported.

CONCLUSION

In this single center series, we showed that CMV reactivation occurs in 23% of the GBM patients having a positive serology for CMV. Reactivation was more frequent in older patients, with low lymphocyte counts and treated with steroids. A positive viremia was not associated with poor PFS, a fact that does not support a promoting role of CMV in glioma oncogenesis, which has been sometimes suggested. Yet, the group of patients with CMV reactivation showed a shorter OS, which might be related to an older age and /or poorer clinical conditions in this group.

P14.20 Anxiety level in a prospective cohort of newly diagnosed glioblastoma patients: preliminary results from the IMAGE study

BACKGROUND

Quality of life (QoL) is an important area of clinical neuro-oncology, especially in glioblastoma patients. Although previous studies showed an association between QoL and anxiety, few studies have focused on the anxiety level throughout the disease progression (Bunevicius et al., 2017; Kilbride et al., 2007). Underestimating anxiety may have several consequences: a low treatment compliance, exacerbation of somatic symptoms or side effects of treatment, difficulties with understanding medical information and lower cooperation with the medical staff (Spencer, 2010). In the present study, we aimed assessing the current state of anxiety in a prospective cohort of patients treated for glioblastoma. We also investigated potential correlations with other clinical and psychological variables to better understand determinants of anxiety in this population.

MATERIAL AND METHODS

At the beginning of their cycle of temozolomide cure and after radio-chemotherapy, 30 patients with glioblastoma were included. Inclusion criteria were: Karnofsky index (IK) ≥ 70% and absence of cognitive disorder that could interfere with the completion of questionnaires. The characteristics of patients were as follows: mean age of 56.6 years ± 12.5 (70% were more than 50 years old); 20% were women; 50% had a university degree and IK of 87% ± 5. Anxiety level was assessed using the State-Trait Anxiety Inventory. This scale consists of 40 items on a self-report basis measuring how patients feel right now (“state”) and how they generally feel (“trait”). We also assessed (i) QoL using the Cancer Quality of Life Questionnaire 30 and the Brain Cancer Module-20; (ii) the presence of depressive symptoms using the Hospital Anxiety and Depression Scale; (iii) the self-esteem using the Rosenberg self-esteem scale and (iv) memory complains using the Prospective and Retrospective Memory Questionnaire.

RESULTS

The preliminary results showed that - at baseline - 21% of our sample reported high levels of anxiety. Correlation analyses showed that state anxiety was correlated with trait anxiety (rho=0.799, p< .001), QoL (rho=0.678, p< .001), level of self-esteem (rho=-0.514, p=0.004) and memory complains (rho=0.618, p< .001). Any correlation was found with age, education level, lesional lateralization or depressive symptoms. Women had higher state anxiety scores than men (t(27)=-2.4, p=0.02).

CONCLUSION

These preliminary results suggest that higher current state of anxiety is associated with lower QoL and lower self-esteem, regardless the presence of depressive symptoms, age, education level or lesional lateralization. Anxiety level at the follow-up (4 and 6 months after the baseline) and determinants of its progression will also be presented and might help health professionals to understand patients’ experience and better meet their needs.

Neurological adverse events associated with immune checkpoint inhibitors: Review of the literature

Immune checkpoint inhibitors (ICIs) targeting CTLA4 and PD1 constitute a promising class of cancer treatment but are associated with several immune-related disorders. We here review the literature reporting neurological adverse events (nAEs) associated with ICIs. A systematic search of literature, up to February 2016, mentioning nAEs in patients treated with ICIs was conducted. Eligible studies included case reports and prospective trials. One case seen in our ward was also added. Within the 59 clinical trials (totalling 9208 patients) analysed, the overall incidence of nAEs was 3.8% with anti-CTLA4 antibodies, 6.1% with anti-PD1 antibodies, and 12.0% with the combination of both. The clinical spectrum of neurological disorders was highly heterogeneous. Most of these nAEs were grade 1-2 and consisted of non-specific symptoms such as headache (55%). The incidence of high grade nAEs was below 1% for all types of treatment. Headaches, encephalopathies and meningitis were the most commonly reported (21%, 19% and 15%, respectively). Among the 27 case reports, the most common nAEs were encephalopathies, meningoradiculoneuritis, Guillain-Barré like syndromes and myasthenic syndromes. The median time of nAEs onset was 6 weeks. In most cases, drug interruption and steroids led to neurological recovery, even in conditions where steroids are not usually recommended such as Guillain-Barré syndrome.

Role of 3D Display MR Angiography in the Study of Intracranial Aneurysms

This paper determines the usefulness of three-dimensional (3D) phase-contrast (PC) magnetic resonance (MR) angiography with 3D display in characterizing large intracranial saccular aneurysms.

Eight patients referred for non invasive confirmation of unruptured aneurysm (n=9) detected by conventional CT and/or MR imaging were studied by 3D PC (VENC of 20 cm/s, 3 axes) in axial acquisition localised on the circle of Willis using a 0.5 T unit (Vectra, GE). We used 3D display images to assess the feasibility of selective treatment. Results were correlated with catheter angiograms in 3 patients.

In two thirds of the cases, location and size of the orifice, size of the sac, and clarification of parent artery were clearly provided allowing prediction of therapeutic management. In the remaining cases results remained doubful because of lack of spatial resolution. The benefit of the method was coupled with the clinical status of the patients to influence the final decision.

3D PC MR angiography with 3D display has emerged as an improvement in predicting therapeutic management, and is especially useful in large unruptured aneurysms in elderly or ill patients.

Impact of renin-angiotensin system blockade on clinical outcome in glioblastoma

BACKGROUND AND PURPOSE

Despite surgery, radiotherapy (RT) and temozolomide (TMZ), the prognosis of glioblastoma (GBM) patients remains dismal. Normally prescribed with the aim to lower blood pressure, angiotensin-II (Ang-II) inhibitors were reported to reduce angiogenesis and tumour growth in several tumour models including one glioma. Thus whether treatment with Ang-II inhibitors could be associated with a better clinical outcome in GBM patients was investigated.

METHODS

A series of 81 consecutive patients, homogeneously treated with RT and TMZ for a newly diagnosed, supratentorial GBM, were analysed. The objective of this retrospective study was to assess the impact of angiotensin-converting enzyme inhibitors (ACEIs) and Ang-II receptor 1 blockers (ARBs) on functional independence, progression-free survival (PFS) and overall survival (OS).

RESULTS

Amongst the 81 GBM patients analysed, 26 were already treated for high blood pressure (seven with ACEIs and 19 with ARBs). The number of patients who remained functionally independent at 6 months after RT was higher in the group of patients treated with Ang-II inhibitors compared to the other patients (85% vs. 56%, P = 0.01). In patients treated with Ang-II inhibitors, PFS was 8.7 months (vs. 7.2 months in the other patients) and OS was 16.7 months (vs. 12.9 months). The use of Ang-II inhibitors was a significant prognostic factor for both PFS (P = 0.04) and OS (P = 0.04) in multivariate analysis.

CONCLUSION

Treatment with Ang-II inhibitors in combination with RT and TMZ might improve clinical outcome in GBMs. Prospective trials are needed to test this hypothesis.

[Supportive care, cognition and quality of life in brain metastases]

Brain metastases impact on the survival of the patients, but on their quality of life as well. The objective of the management of these patients is then double. Currently, due to medical advances, survivals tend to improve, especially for some tumor subtypes. During the course of the disease, different neurological signs and symptoms can be observed according to the location, the number and the volume of the metastase(s). Patients and caregivers are especially worried about the loss of autonomy and cognitive impairments. A permanent dialogue, during the course of the disease, is mandatory, in order to adapt the management to the objectives determined by the patients and the medical team. These objectives may vary according to the objective response rates of the disease to anticancer therapies, according to the impact of the disease and its management in daily living. Anticancer therapies and supportive care must be appreciated according to their impact on the survival, on the preservation of the functional independence and the quality of life of the patient, on their abilities to preserve the neurological status and delay the apparition of new neurological signs and symptoms, and their adverse events. Supportive care, cognition and quality of life should be regularly evaluated and adapted according to the objectives of the management of brain metastases patients. Different approaches are described in this paper.

A comprehensive study of thiol reduction gene expression under stress conditions in Arabidopsis thaliana

Thiol reduction proteins are key regulators of the redox state of the cell, managing development and stress response programs. In plants, thiol reduction proteins, namely thioredoxin (TRX), glutaredoxin (GRX), and their respective reducers glutathione reductase (GR) and thioredoxin reductase (TR), are organized in complex multigene families. In order to decipher the function of the different proteins, it is necessary to have a clear picture of their respective expression profiles. By collecting information from gene expression databases, we have performed a comprehensive in silico study of the expression of all members of different classes of thiol reduction genes (TRX, GRX) in Arabidopsis thaliana. Tissue expression profiles and response to many biotic and abiotic stress conditions have been studied systematically. Altogether, the significance of our data is discussed with respect to published biochemical and genetic studies.

PreFix™ external fixator used to treat a floating shoulder injury caused by gunshot wound

Open fractures of the shoulder are extremely rare, and their treatment is a major challenge for surgeons. Only cases encountered in military settings have been reported thus far. Such fractures are often the result of ballistic trauma, which causes extensive damage to both bony and soft tissues. Since these injuries are associated with a high risk of infection and the presence of comminuted fractures, external fixation is necessary for repair. Use of external fixators and revascularization techniques has reduced the number of cases requiring shoulder amputation or disarticulation. Injury to the proximal extremity of the humerus, acromion, and clavicle further complicates the treatment. No published studies have described the assembly of external fixators for fractures in the scapular region with significant bone loss. In addition, no cases have been described in civilian settings. However, with an increase in urban violence and the traffic of illegal arms, civilian surgeons are now encountering an increasing number of patients with these injuries. In this report, we not only present a rare case of floating shoulder injury in a civilian setting but also provide an overview of the existing treatment strategies for this type of trauma, with special focus on the use of external fixators in elective shoulder arthrodesis and on military cases.

Steroid-sparing effects of angiotensin-II inhibitors in glioblastoma patients

BACKGROUND

The standard of care in patients with glioblastoma (GBM) relies on surgical resection, radiation therapy (RT), and temozolomide. Steroids are required in almost all patients to reduce peritumoral edema, but are associated with numerous side effects. Vascular endothelial growth factor (VEGF) is a key driver of peritumoral edema and angiogenesis in human GBM. Recently, angiotensin-II inhibitors were reported to reduce VEGF secretion and tumor growth in some animal models.

METHODS

To investigate whether angiotensin-II inhibitors might have a similar effect in humans and before undertaking a prospective study, we retrospectively investigated a series of 87 consecutive, newly diagnosed GBM patients, treated in a single center. Amongst these patients, 29 (33%) were already treated before RT for high blood pressure (HBP), 18 of them (21%) with an angiotensin-II inhibitor. In all patients, performance status, surgical procedures, and steroid dosages were documented.

RESULTS

Patients treated with angiotensin-II inhibitors, but not other antihypertensive drugs, required half of the steroids of the other patients during radiotherapy (P = 0.005 in multivariate analysis, considering other antihypertensive treatments, surgical resection, and performance status). This effect of angiotensin-II inhibitors was also significant at the beginning of radiotherapy (P = 0.03 in multivariate analysis). Treatment with angiotensin-II inhibitors had no effect on survival (16.2 vs. 17.9 months for the treated and the non-treated group, respectively, P = 0.77).

CONCLUSION

Angiotensin-II inhibitors might display significant steroid-sparing effects in brain tumor patients. Given the morbidity associated with steroids, this finding might have important practical consequences in these patients and warrants a randomized study.

Impact of storage induced outgassing organic contamination on laser induced damage of silica optics at 351 nm

The impact of storage conditions on laser induced damage density at 351 nm on bare fused polished silica samples has been studied. Intentionally outgassing of polypropylene pieces on silica samples was done. We evidenced an important increase of laser induced damage density on contaminated samples demonstrating that storage could limit optics lifetime performances. Atomic Force Microscopy (AFM) and Gas Chromatography -Mass Spectrometry (GC-MS) have been used to identify the potential causes of this effect. It shows that a small quantity of organic contamination deposited on silica surface is responsible for this degradation. Various hypotheses are proposed to explain the damage mechanism. The more likely hypothesis is a coupling between surface defects of optics and organic contaminants.

Cognitive function and 99mTc-ECD brain SPECT are significantly correlated in patients with primary Sjögren syndrome: a case–control study

Objectives:

To assess subclinical central nervous system (CNS) involvement in primary Sjögren syndrome (pSS), by comparing standard brain MRI, in-depth neuropsychological testing and 99mTc-ECD brain single-photon emission computed tomography (SPECT) of patients with pSS with matched controls.

Methods:

10 women (<55 years old), with pSS defined using European–American criteria, presence of anti-SSA and/or anti-SSB antibodies and no history of neurological involvement were prospectively investigated, and compared with 10 age- and sex-matched controls. All subjects underwent, within 1 month, brain MRI, neuropsychological testing, including overall evaluation and focal cognitive function assessment, and 99mTc-ECD brain SPECT.

Results:

99mTc-ECD brain SPECT abnormalities were significantly more common in patients with pSS (10/10) than controls (2/10; p<0.05). Cognitive dysfunctions, mainly expressed as executive and visuospatial disorders, were also significantly more common in patients with pSS (8/10) than controls (0/10; p<0.01). Notably, between-group comparisons enabled a significant correlation to be established between neuropsychological assessment and 99mTc-ECD brain SPECT abnormalities in patients with pSS (rs = 0.49, p<0.01). MRI abnormalities in patients and controls did not differ significantly.

Conclusions:

Neuropsychological testing and 99mTc-ECD brain SPECT seem to be the most sensitive tools to detect subclinical CNS dysfunction in pSS. The strong correlation between cortical hypoperfusion in 99mTc-ECD brain SPECT and cognitive dysfunction suggests an organic aetiology of CNS dysfunction in pSS. These data should be confirmed in a larger study.

[Hemispheric specialisation versus inter-hemispheric communication]

The first part of this article covers the main discoveries that led to the concept of hemispheric specialisation, from Egyptian antiquity to present times, through the pivotal XIXth century period that saw the attribution of specific cognitive functions to the left and right hemispheres. Next, this dichotomous conception of cerebral function, attributing a given process to a hemisphere and hypothesising callosal transmission, is discussed in the light of recent studies on language comprehension. Present day knowledge suggesting an alternative to the structuralist view of hemispheric specialisation in the form of dynamic, complementary sharing of labour, and of cooperation through transcortical neural networks, is then considered. Finally, the role of the corpus callosum in interhemispheric communication is briefly covered. An emphasis is placed on the diversity of this structure that is at the origin of highly different functions (fibre size, homotopic vs heterotopic connections). Ultimately, we contrast the view of a corpus callosum serving as an information transmitting channel with that of a fibre tract co-activating the non-engaged hemisphere and preparing it for potential stimulation. In this manner, the corpus callosum minimises disparities in the distribution of attention between the two hemispheres.

[Intracranial localization revealing Hodgkin's disease]

The central nervous system's (CNS) involvement is uncommon in Hodgkin's disease (HD) and usually occurs in patients with relapsing disease many years after the initial diagnosis. An isolated involvement of the CNS is extremely rare and therefore, difficult to diagnosis. We report the case of a 27-year-old woman with seizure and a left cerebrodural mass on the cerebral imaging; secondarily, she developed cervical lymph node swelling; histological examination of the node revealed HD of the nodular sclerosis type. The dural lesion resolved after chemotherapy for HD.

Hémiparésie d’installation progressive révélant une encéphalite à listéria monocytogènes

INTRODUCTION

Central nervous system listeriosis is a diagnostic and therapeutic challenge for the clinician.

CASE REPORT

We report the case of a 66-year-old woman who was admitted for a left progressive hemiparesis associated with headaches. She was treated for one year by immunosuppressive drugs for vulgaris pemphigus. At the time of admission, examination revealed left hemiparesis without fever, and a computed tomography brain scan demonstrated a focal lesion in the right frontal lobe. Blood analyses were normal. Two days after, she suddenly developed fever (40 degrees C), and aggravation of her motor deficit followed by partial motor seizures. The cerebrospinal fluid was normal. Treatment with amoxicillin (3g IV q6h), cefotaxim, gentamycin (120mg IV q12h) and aciclovir was started empirically. The brain MRI without gadolinium displayed infiltrative lesions in the right hemisphere and in the mildbrain. The blood culture grew Listeria monocytogenes. The antimicrobial regimen was changed to amoxicillin for seven weeks and gentamicin for the first ten days. Four days after beginning the antimicrobial regimen, the brain MRI with gadolinium displayed several abscesses measuring less than one cm diameter. The clinical and imaging outcome excellent.

CONCLUSION

Meningitis is by far the most central nervous system listeriosis. In our patient, the diagnosis of listeria monocytogenes encephalitis was established on the basis of positive blood cultures, as such patients do not have sterile cerebrospinal fluid.

Conformational analysis and crystal structure of {[1-(3-chloro-4-fluorobenzoyl)-4-fluoropiperidin-4yl]methyl}[(5-methylpyridin-2-yl)methyl]amine, fumaric acid salt

{[1-(3-Chloro-4-fluorobenzoyl)-4-fluoropiperidin-4yl]methyl}[(5-methylpyridin-2-yl)methyl]amine, fumaric acid salt (C(20)H(22)ClF(2)N(3)O, C(4)H(4)O(4)) (1) was synthesized and characterized by the complete (1)H, (13)C and (19)F NMR analyses. The conformation of the piperidin ring, in the solution state, was particularly studied from the coupling constants determined by recording a double-quantum filtered COSY experiment in phase-sensitive mode. (1)H NMR line-shape analysis was used, at temperatures varying between -5 and +60 degrees C, to determine the enthalpy of activation of the rotational barrier around the CN bond. Compound 1 crystallizes in the triclinic space group P1 with a=8.517(3) Angstrom, b=12.384(2) Angstrom, c=12.472(3) Angstrom, alpha=70.88(2) degrees, beta=82.04(2) degrees, gamma=83.58(2) degrees. The results strongly indicate that the solid and solution conformations are similar. Thermal stability and phases transitions were investigated by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). Furthermore polymorphism screening was studied from recrystallization of 1 performed in seven solvents and by slurry conversion in water. The X-ray powder diffraction (XRPD) and differential scanning calorimetry results suggested that 1 crystallizes into one crystalline form which melts at 157 degrees C (DeltaH=132 J g(-1)).

Grafted self-assembled monolayers derived from naturally occurring phenolic lipids

Self-assembled monolayers grafted onto silicon surfaces were obtained from the hydrosilylation products by trialcoxysilanes of naturally occurring phenolic lipid allyl ethers. The as-obtained materials were characterized by various physical and physicochemical methods. Thus, contact angles of water drops showed that they possess very high hydrophobicity. Their excellent regularity was corroborated by AFM microscopy. The frequencies of the stretching CH2 infrared modes indicate the presence of alkyl chains mainly in the trans/trans conformation. Additionally, optical ellipsometry and quartz microbalance measurements enabled us to estimate the thickness of the films. The results, as a whole, are in good agreement with the formation of densely packed monolayers.

Clinical callosum syndrome in a case of multiple sclerosis

This case report confirms that a clinical callosal disconnection could be observed in multiple sclerosis. Moreover, this case describes a new kind of strange manual behavior related to callosal disconnection. This behavior could neither be considered as a diagonistic dyspraxia nor as an alien hand, but they evoke rather a conflict of intentions.

Organic colloid separation in contrasting aquatic environments with tangential flow filtration

The use of tangential flow filtration (TFF) for size fractionation of natural dissolved organic matter was investigated. The performance of regenerated cellulose membrane with a nominal molecular weight cut-off of 1 kDa was examined on 20 samples from lake, river and estuary systems, characterised by contrasting dissolved organic carbon (DOC) contents and conductivity. The evaluation was based on absorbance, fluorescence and DOC measurements. Detailed protocols of membrane cleaning and conditioning nation are proposed. The ultrafiltration membrane can efficiently be cleaned to provide low carbon blank (<0.01 mg/L). Fluorescence measurements confirmed that the higher molecular weight compounds were isolated in the retentate and the lower molecular weight remain in the permeate. Mass balance for natural samples show good recovery for DOC (109 +/- 12%, n = 20) and fluorescence measurements (106 +/- 9%, n = 13). No relation between factors of concentration (fc) and mass balance quality was observed for the fc range 1.5-11. Moreover, high ionic strength and high DOC contents did not enhance membrane fouling. These findings demonstrate that reliable fractionations by TFF of natural organic colloids in aquatic systems can be achieved.

Involvement of RNA2-encoded proteins in the specific transmission of Grapevine fanleaf virus by its nematode vector Xiphinema index

The nepovirus Grapevine fanleaf virus (GFLV) is specifically transmitted by the nematode Xiphinema index. To identify the RNA2-encoded proteins involved in X. index-mediated spread of GFLV, chimeric RNA2 constructs were engineered by replacing the 2A, 2B(MP), and/or 2C(CP) sequences of GFLV with their counterparts in Arabis mosaic virus (ArMV), a closely related nepovirus which is transmitted by Xiphinema diversicaudatum but not by X. index. Among the recombinant viruses obtained from transcripts of GFLV RNA1 and chimeric RNA2, only those which contained the 2C(CP) gene (504 aa) and 2B(MP) contiguous 9 C-terminal residues of GFLV were transmitted by X. index as efficiently as natural and synthetic wild-type GFLV, regardless of the origin of the 2A and 2B(MP) genes. As expected, ArMV was not transmitted probably because it is not retained by X. index. These results indicate that the determinants responsible for the specific spread of GFLV by X. index are located within the 513 C-terminal residues of the polyprotein encoded by RNA2.

Ecological analysis of digestive cancer mortality related to contamination by diarrhetic shellfish poisoning toxins along the coasts of France

Shellfish consumers are exposed to the risk of diarrhea from, among other contaminants, algae that produce diarrhetic shellfish poisoning (DSP) toxins, such as Dinophysis spp. These illnesses have been effectively prevented since 1984, when a phycotoxin monitoring network was set up along the coasts of France. There is nonetheless concern that residual levels of okadaic acid, a known tumor promoter that is the main toxin present in French coastal waters, might increase the risk of cancer among regular shellfish consumers. To test this hypothesis, we conducted an ecological study linking digestive cancer mortality rates with a proxy measure of contamination by DSP toxins in 59 coastal areas. Observed and expected numbers of deaths (using national rates as the reference) were computed by sex, cause of death, and area for two time periods: 1984-1988 and 1989-1993. The level of contamination in each area was estimated by the total number of weeks since monitoring began that production was shut down because of DSP toxin contamination. Using both Poisson regressions and test for trends of standardized mortality ratios across four exposure categories, we found some evidence of associations for several digestive cancer sites (esophagus, stomach, colon, liver, and total digestive cancers for men; stomach and pancreatic cancers for women). Among men, the only statistically significant result that remained after taking possible confounding by alcohol use into account involved colon cancer. The conclusions provided by this analysis are very tentative; they need to be reproduced and interpreted in the light of additional information on the potential long-term effects of DSP toxins. In the absence of human data, they provide some indication of a possible association between exposure to DSP toxins and digestive cancers.

Failure to identify the target does not prevent the attentional blink effect

The attentional blink has been attributed to capacity limitations at a central level of processing. We tested whether failure to identify the target would eliminate the blink. Two agnostic patients were presented with streams of letters, which they were able to identify, and streams of pictures, which they were unable to identify. The dual-task involved identification of a target and detection of a probe. With letters the duration of the blink was equivalent to that of the control subjects. A prolonged blink was observed in both patients for pictures irrespective of whether the target was identified. This result indicates that failure to identify the target does nevertheless mobilize attentional resources sufficiently to prevent detection of a second target stimulus.

Potassium barium bismuth oxide

KBa(4)Bi(3)O crystallizes in the centrosymmetric tetragonal space group I4/mcm. In this compound, bismuth is present as two anionic species, i.e. Bi(2)(4-) dumbbells [Bi-Bi 3.113 (3) A] and isolated Bi(3-). Atom Bi1 (Bi(3-)) lies inside a bicapped square antiprism (2 x K and 8 x Ba). Atom Bi2, which forms the Bi(2)(4-) dumbbell, sits inside a bicapped distorted trigonal prism (2 x K and 6 x Ba). O atoms occupy tetrahedral voids between Ba atoms.

Icosahedron oligomerization and condensation in intermetallic compounds. Bonding and electronic requirements

Icosahedron-based clustering has been found to be very common in intermetallics, particularly for group 13 and early p-block icosogen elements. Linking of the icosahedral building blocks depends on the valence electron concentrations. Vertex-, edge-, or face-sharing icosahedra occur as the structure compensates for electron deficiency. Some examples of icosahedron-based clusters have been selected for an analysis of the relationships between the structural features (icosahedron oligomerization, atomic defects, etc.) and the bonding and electronic requirements. The extended Hückel method has been used with either a molecular approach or an electronic band structure calculation to rationalize bonding in the intermetallic framework.

Central nervous system sarcoidosis: follow-up at MR imaging during steroid therapy

PURPOSE

To document the changes observed at sequential magnetic resonance (MR) imaging of sarcoidosis lesions of the central nervous system (CNS) during treatment with corticosteroids.

MATERIALS AND METHODS

The abnormalities detected in 24 patients (mean follow-up, 36 months) were compared before and after therapeutic periods (n = 75) that were divided into attack (high-dose), upkeep (decreased-dose), and minimal (low-dose) periods. Parenchymal lesions were classified as type 1 (enhanced with gadolinium), type 2 (demyelinating), or type 3 (lacunar) and were assessed as regressing, stable, or progressing.

RESULTS

Seven of the 24 patients had several types of lesions. Isolated type 3 lesions (six patients) were the only lesions not associated with neurologic deficit. Type 1 lesions (13 patients) regressed in 22 of 22 attack periods and progressed in nine of 27 upkeep and minimal periods. MR imaging depicted relapses in patients with multifocal CNS involvement or long-standing CNS impairment or in those who had previously received steroid therapy. Type 2 (seven patients) and type 3 (13 patients) lesions remained stable in 68 of 68 therapeutic periods. Type 1 lesions appeared in three patients with type 2 and type 3 lesions during two upkeep and three minimal periods. Findings at follow-up MR imaging contributed to the reintroduction of high-dose corticosteroid therapy in eight patients.

CONCLUSION

MR imaging can be used to differentiate between reversible and irreversible lesions in CNS sarcoidosis. MR imaging can be a useful tool for adjusting treatment to prevent irreversible CNS damage.