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Objectives: The movement towards personalization of cochlear implantation has continued to generate interest about variabilities in cochlear size. In a recent meta-analysis, Atalay et al. (2022) examined organ of corti length, cochlear lateral wall, and “A” value and found that most covariates, other than congenital sensorineural hearing loss, did not impact cochlear size via these measurements. However, no meta-analysis exists on how patient-specific variables could impact other cochlear size measurements, such as cochlear height (CH), and “B” value (defined as the distance between opposite lateral walls and perpendicular to “A” value). The purpose of this systematic review and meta-analysis is to examine how patient-specific variables impact additional cochlear size measurements to assist clinical decision-making. Databases reviewed: A systematic review for cochlear size measurements using PRISMA methodology was performed using PubMed, CINAHL, and MEDLINE from database inception to October 1st, 2022. Methods: Search terms used included English, cochlea, size, histology, anatomy, and human. Inclusion criteria were measurements for human cochlea, full-text articles, and articles in English. Primary measurements were “B” value and CH, as these measurements differ from the recent meta-analysis on this topic. Cochlear duct length (CDL) was also included. A random-effects continuous model for meta-analysis was performed. Measurements were stratified by gender (male/female) and disease type (sensorineural hearing loss (SNHL)/conductive hearing loss (CHL)). Results: A total of 7 articles met final inclusion criteria from a total of 674 articles received on initial search, resulting in 2263 total human cochleae. There was a statistical difference between male CDL (n = 681 cochlea) compared to female CDL (n = 657) from four articles (p

An evaluation of the radiation shielding performance of high-Z-particle-loaded polylactic acid (PLA) composite materials was pursued. Specimens were produced via fused deposition modeling (FDM) using copper-PLA, steel-PLA, and BaSO4-PLA composite filaments containing 82.7, 75.2, and 44.6 wt% particulate phase contents, respectively, and were tested under broad-band flash x-ray conditions at the Sandia National Laboratories HERMES III facility. The experimental results for the mass attenuation coefficients of the composites were found to be in good agreement with GEANT4 simulations carried out using the same exposure conditions and an atomistic mixture as a model for the composite materials. Further simulation studies, focusing on the Cu-PLA composite system, were used to explore a shield design parameter space (in this case, defined by Cu-particle loading and shield areal density) to assess performance under both high-energy photon and electron fluxes over an incident energy range of 0.5–15 MeV. Based on these results, a method is proposed that can assist in the visualization and isolation of shield parameter coordinate sets that optimize performance under targeted radiation characteristics (type, energy). For electron flux shielding, an empirical relationship was found between areal density (AD), electron energy (E), composition and performance. In cases where EAD≥2 MeV∙cm∙g−1, a shield composed of >85 wt% Cu results in optimal performance. In contrast, a shield composed of

The techniques described allow the quantitation of cholesterol, cerebrosides, sulfatides, ethanolamine phospholipids, phosphatidylcholine, -serine, -inositol, and gangliosides on 500 micrograms of lipid. Lipid extraction required sonication. Separation of the lipid classes was performed on TLC glass plates (10 x 10 cm) coated with silica gel HPTLC 60 F 254 Merck using one multiple two-dimensional chromatography. Most of the methods used for quantitation were standard methods that had been scaled down. The procedure was applied to study regional differences in the central nervous system, to analyze cell membranes or subcellular particles, or to analyze pathological biopsies in the central and peripheral nervous systems.

Background: The German Cancer Society (DKG) board certifies hospitals in treating esophageal, gastric, liver and pancreatic cancer among others. There has been no systematic verification of the number of major surgical resections set by DKG certification with regards to in-house mortality and failure to rescue (FtR)., Methods: This is a retrospective analysis of anonymized nationwide hospital billing data (DRG data, 2009-2017). Inclusion criteria were based on the annual surgical minimum caseload (SMC) in accordance with DKG certification., Results: 171,429 datasets were identified, including 31,140 esophageal, 54,155 gastric, 57,343 pancreatic and 28,791 liver resections. In-house mortality ranged from 6.2% for gastric resections to 8.1% for pancreatic resections. Differences in in-house mortality between hospitals which fulfilled SMC on average and those which did not fulfill SMC on average were 40.8% (5.3% vs 8.2%) for esophageal, 32.3% (4.8% vs 6.8%) for gastric and 45.7% (6.1% vs 9.8%) for pancreatic resections, while it was 8.2% higher in SMC-hospitals (7.6% vs 7.0%) for liver resections. Complication occurrence rates for esophageal, gastric and pancreatic resections were similar in SMC- and non-SMC-hospitals while FtR in hospitals fulfilling SMC was significantly lower. Data for liver resections demonstrated the same trends only in a sub-analysis of complex procedures., Conclusion: This study demonstrates an association between caseload threshold defined by DKG and lower mortality in esophageal, gastric, pancreatic and complex liver surgery. In these resections, FtR was reduced if SMC was fulfilled., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2021 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.)

Background: Early motor coordination problems have previously been associated with various developmental outcomes at school-age., Aims: Investigate whether and how treatment with physiotherapy may alter associations between early motor problems and subsequent developmental outcomes., Study Design: A prospective whole-population study., Subjects: 1374 children were followed from birth to 8 years., Outcome Measures: Early motor functioning was determined with standard neurological examinations at birth and at 5 months. Information on receipt of physiotherapy was collected through parent interviews at 5, 20 and 56 months. Developmental outcomes at 6 and 8 years included motor skills, mental health, cognitive function, and attention regulation and were determined through standard tests, parent reports and observed behavior ratings., Results: Early motor problems were associated with lower motor skills, cognitive function, and attention regulation at school-age, but not with mental health. In addition to early motor problems, receipt of physiotherapy was independently and negatively related to outcomes at school-age. Accounting for imbalances in covariates, including initial motor scores, via propensity score matching attenuated the adverse effects of receipt of physiotherapy on school-aged outcomes., Conclusions: Infant motor problems are associated with motor and cognitive outcomes at school-age. Early motor problems may represent a starting point of a trajectory of difficulties that may lead to a higher risk of problems in multiple developmental domains. No evidence for a beneficial effect of treatment with physiotherapy was found., Competing Interests: Declaration of competing interest All authors report no financial interests or potential conflicts of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

People can intuitively estimate the semantic coherence of word triads, even when they are unable to state the triads' common denominator. The present research examines the role of working memory in such intuitive coherence judgments. Dual-process models of information processing suggest that intuition does not depend on working memory. Consistent with this, the authors predicted that taxing working memory capacity will not lower the accuracy of intuitive coherence judgments. Nevertheless, taxing working memory may impede metacognitive processing, which may lead people to become more conservative in judging triads as coherent. Two studies (combined N = 307) tested these predictions by asking participants to memorize letter-number combinations of varying lengths while providing intuitive coherence judgments. As expected, working memory load had no effect on the accuracy of intuitive coherence judgments (Studies 1 & 2). Effects on judgment bias were less consistent. In Study 1, participants became slightly more conservative in judging triads as coherent under moderate (compared to low) working memory load. In Study 2, which was preregistered, working memory load led to more conservative intuitive coherence judgments, but only when participants prioritized a highly demanding load task. Unexpectedly, when focusing on a moderate (compared to a low) working memory load, participants were more liberal in judging triads as coherent. Together, these findings indicate that taxing working memory may interfere with people's inclination to trust their intuition, even when it leaves the accuracy of people's intuition intact., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background and Aims: To determine the combined impact of infant multiple/persistent regulatory problems (RPs), parenting quality and maternal mental health on childhood attention problems., Study Design: A prospective, population-based cohort study including 16 paediatric hospitals in Southern Bavaria (Germany)., Subjects: 1459 infants were followed from birth to 8 years of age., Outcome Measures: RPs were assessed at 5 and 20 months using interviews by trained paediatricians; parenting quality was assessed between birth and 5 months using parent interviews and nurses' observations; maternal mental health was assessed at birth and 5 months using standardized parents' interviews; childhood data on attention problems were collected at 8 years, using parent reports and expert behaviour observation ratings., Results: After correction for gestational age, sex, and socioeconomic status, early RPs (β = 0.079) and low parenting quality (β = 0.175) predicted later attention problems (R 2  = 0.272). Their impact was additive, such that infants with both multiple/persistent RPs and poor parenting quality showed the highest attention problems 8 years later. However, the impact of RPs on attention was strongest for preterm children. Maternal mental health was a significant moderator of the relationship between parenting quality and attention problems. With adequate maternal mental health, good parenting quality was related to lower attention problems, yet with mental health problems present, the effect of good parenting on attention problems diminished., Conclusions: Guidance and support for parents of infants with multiple/persistent crying, sleeping or feeding problems may be essential to prevent the development of childhood attention problems, especially when maternal mental health problems are present., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Prematurely born individuals have an increased risk for long-term neurocognitive impairments. In animal models, development of the cholinergic basal forebrain (cBF) is selectively vulnerable to adverse effects of perinatal stressors, and impaired cBF integrity results in lasting cognitive deficits. We hypothesized that cBF integrity is impaired in prematurely born individuals and mediates adult cognitive impairments associated with prematurity., Methods: We used magnetic resonance imaging-based volumetric assessments of a cytoarchitectonically defined cBF region of interest to determine differences in cBF integrity between 99 adults who were born very preterm and/or with very low birth weight and 106 term-born control subjects from the same birth cohort. Magnetic resonance imaging-derived cBF volumes were studied in relation to neonatal clinical complications after delivery and intelligence measures (IQ) in adulthood., Results: In adults who were born very preterm and/or with very low birth weight, cBF volumes were significantly reduced compared with term-born adults (-4.5% [F 1,202 = 11.82, p = .001]). Lower cBF volume in adults who were born very preterm and/or with very low birth weight was specifically associated with both neonatal complications (r part,92 = -.35, p < .001) and adult IQ (r part,88 = .33, p = .001) even after controlling for global gray matter and white matter volume. In a path analytic model, cBF volume significantly mediated the association between neonatal complications and adult cognitive deficits., Conclusions: We provide first-time evidence in humans that cBF integrity is impaired after premature birth and links neonatal complications with long-term cognitive outcome. Data suggest that cholinergic system abnormalities may play a relevant role for long-term neurocognitive impairments associated with premature delivery., (Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Historic mining in the Eastern Alps has left us with a legacy of numerous spoil heaps hosting specific, metal tolerant vegetation. Such habitats are characterized by elevated concentrations of toxic elements but also by high irradiation, a poorly developed substrate or extreme pH of the soil. This study investigates the distribution of vascular plants, mosses and lichens on a copper spoil heap on the ore bearing Knappenberg formed by Prebichl Layers and Werfener Schist in Lower Austria. It serves as a model for discriminating between various ecological traits and their effects on vegetation. Five distinct clusters were distinguished: (1) The bare, metal rich Central Spoil Heap was only colonised by highly resistant specialists. (2) The Northern and (3) Southern Peripheries contained less copper; the contrasting vegetation was best explained by the different microclimate. (4) A forest over acidic bedrock hosted a vegetation overlapping with the periphery of the spoil heap. (5) A forest over calcareous bedrock was similar to the spoil heap with regard to pH and humus content but hosted a vegetation differing strongly to all other habitats. Among the multiple toxic elements at the spoil heap, only Cu seems to exert a crucial influence on the vegetation pattern. Besides metal concentrations, irradiation, humidity, humus, pH and grain size distribution are important for the establishment of a metal tolerant vegetation. The difference between the species poor Northern and the diverse Southern Periphery can be explained by the microclimate rather than by the substrate. All plant species penetrating from the forest into the periphery of the spoil heap originate from the acidic but not from the calcareous bedrock., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Very preterm birth is associated with an increased prevalence of attention problems and may especially impair executive attention, i.e., top-down control of attentional selection in situations where distracting information interferes with the processing of task-relevant stimuli. While there are initial findings linking structural brain alterations in preterm-born individuals with attention problems, the functional basis of these problems are not well understood. The present study used an fMRI adaptation of the Attentional Network Test to examine the neural correlates of executive attention in a large sample of N = 86 adults born very preterm and/or with very low birth weight (VP/VLBW), and N = 100 term-born controls. Executive attention was measured by comparing task behavior and brain activations associated with the processing of incongruent vs. congruent arrow flanker stimuli. Consistent with subtle impairments of executive attention, the VP/VLBW group showed lower accuracy and a tendency for increased response times during the processing of incongruent stimuli. Both groups showed similar activation patters, especially within expected fronto-cingulo-parietal areas, but no significant between-group differences. Our results argue for a maintained attention-relevant network organization in high-functioning preterm born adults in spite of subtle deficits in executive attention. Gestational age and neonatal treatment variables showed associations with task behavior, and brain activation in the dorsal ACC and lateral occipital areas, suggesting that the degree of prematurity (and related neonatal complications) has subtle modulatory influences on executive attention processing.

Purpose: Although sensitive and cognitively stimulating parenting is a powerful predictor of school success, it may not protect against increased neonatal risk resulting from underlying neurological damage., Methods: A total of 314 very preterm/very low birth weight (VP/VLBW) and 338 term control children were studied from birth to age 13 years. Socioeconomic status was examined at birth. Neurological and physical impairment was assessed at age 20 months, and sensitive and cognitively stimulating parenting at age 6 years. School success was measured from 6 to 13 years of age., Results: Very preterm/very low birth weight children had lower school success between 6 and 13 years, after statistically controlling for child disability and socioeconomic status. Cognitively stimulating parenting promoted all children's school success whereas highly sensitive parenting at age 6 years partly protected against the adverse effects of VP/VLBW birth on academic outcomes., Conclusions: Very preterm/very low birth weight children's school success to age 13 years may be partly protected with sensitive parenting in middle childhood, despite the neurodevelopmental impairments associated with VP/VLBW birth. This suggests potential avenues for interventions for children born at high neonatal risk., (Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Synthetically prepared boltwoodite and compreignacite were characterized with time-resolved laser-induced fluorescence spectroscopy (TRLFS). The obtained TRLFS emission spectra of both synthesized uranium minerals differ from each other in their positions of the vibronic peak maxima and in their fluorescence lifetimes. Also, the shapes of the spectra and their respective intensities are different. The TRLFS-spectrum of boltwoodite showed well-resolved sharp vibronic peaks at 485.1, 501.5, 521.2, 543.0, 567.4, and 591.4nm with deep notches between them and compreignacite is characterized by two broad peaks with various shoulders. Here five emission bands were identified at 500.7, 516.1, 532.4, 554.3, and 579.6nm. The shape of the TRLFS spectra of compreignacite is typical for uranium in a hydroxide coordination environment. For both minerals two fluorescence lifetimes were extracted. The two species of boltwoodite and compreignacite, respectively, showed the same positions of the peak maxima showing that the coordination environments are similar, but differ in the chemistry and number of possible quenchers, e.g. water molecules and hydroxide groups. For boltwoodite fluorescence lifetimes of 382 and 2130ns, and for compreignacite shorter ones of 202 and 914ns, respectively, were determined. The spectroscopic signatures of the two uranyl minerals reported here could be useful for identifying uranyl(VI) mineral species as colloids, as thin coatings on minerals, as minor component in soils, or as alteration products of nuclear waste.

The "ovarioleukodystrophies" comprise a group of rare leukodystrophies associated with primary or premature ovarian failure. Some of the patients have a variant of "vanishing white matter disease" with mutations in subunits of eukaryotic initiation factor 2B (EIF2B). A 32-year-old woman who developed neurological signs related to an extensive leukoencephalopathy on magnetic resonance imaging (MRI) in the context of amenorrhea since the age of 18 years was found to be homozygous for a mutation in the EIF2B5 gene: c.338G>A/p.Arg113His. She had a progressive disease with development of tetraparesia in less than 6 years. Our observation confirms that ovarian failure in the context of a leukodystrophy warrants mutational analysis of the genes encoding the subunits of EIF2B.

Objective: To report Multiple Sclerosis (MS) in two migrant Indian siblings in the Middle East., Background: MS was thought to be rare in the Indian subcontinent, but, of late, with ready availability of Magnetic Resonance Imaging (MRI) scan, evoked potential studies and immunoglobulin estimation in this part of the developing world, there have been several reports of definite cases of MS from India. However familial MS remains hitherto unreported from the Indian subcontinent., Report: A 39-year-old South Indian Hindu female presented with an episode of hemiparesis which remitted with treatment. Three months later she had a relapse in an acute disseminated form, with residual deficits in gait, vision and mental faculties. MRI revealed discrete and confluent plaques in the centrum semiovale. Four years later, her brother was diagnosed to have central demyelinating disease with discrete and confluent plaques in the cervical cord and corona radiata when he presented at age 39 with neck pain and episodic tonic spasms in the lower limbs. Leucodystrophies were ruled out through appropriate biochemical tests. Cases satisfied diagnostic criteria for MS and were confirmed by follow up. HLA associations were studied. Starting a decade after migration from the South Indian state of Kerala to the Middle East, the disease had slow secondary progression in the female but a stable benign course, so far, in the male sibling., Conclusions/relevance: This is the first case report of familial MS from the Indian subcontinent. Onset of MS in South Indian siblings after several years of stay in the Middle East may support aetiological postulations of gene-environment interactions.

Sphingoglycolipids (SGLs) are cell membrane constituents. As the ceramide structure influences the biological properties of the SGL, we characterized by electrospray ionization tandem mass spectrometry the molecular species of ceramides present in SGL of mouse brain. We report here for the first time the presence in mammalian brain of sphingadienine (d18:2). Sphingenine (d18:1) is present in all SGL species, in contrast to eicosasphingenine (d20:1), which is a constituent of only gangliosides. Sphingadienine is present in galactosylceramide and sulfatides. Free ceramides contain the three types of bases. Thus, there could be two separate pools of free ceramides (d18:1, d18:2 and d20:1, d18:1) as precursors of complex SGL.

Experimental autoimmune encephalomyelitis (EAE) is a T-cell-mediated disorder characterized by infiltration of the central nervous system (CNS) by mononuclear cells and macrophages, and serves as a model for multiple sclerosis. In acute monophasic and relapsing remitting forms of EAE, the CNS inflammatory infiltrates are cleared within a few days and, simultaneously, animals recover from their clinical disability. The mechanisms for rapid disappearance of the inflammatory cells are not fully understood. Fas and Fas-ligand (Fas-L) molecules are thought to play an important role in the deletion of autoimmune reactive T cells through apoptosis. However, recent observations in transgenic lpr and gld mice show that mutations inactivating Fas and Fas-L respectively ameliorate signs of EAE despite persistence of immune cell infiltrates into the CNS. In the current study, the expression of Fas and Fas-L was investigated by immunochemistry and in situ hybridization during the course of EAE in DA rats that were actively immunized with syngenic spinal cord homogenate. CNS apoptotic cells were simultaneously examined using terminal transferase dUTP nick end-labeling techniques. During the acute phase of the disease, a significant proportion of CNS CD4+ cells (80%) and macrophages (50%) expressed Fas and Fas-L (80 and 60%, respectively). Simultaneously, about 20% of CD4+ cells and 30% of macrophages were found to be apoptotic. Some astrocytes and neurons also expressed Fas and Fas-L, although they did not appear to be apoptotic. These results further support a role for Fas-mediated lymphocyte and macrophage apoptosis in this model of CNS autoimmune disease but they also suggest a more complex role for Fas/Fas-L interactions in CNS autoimmunity, including resident cells.

We report an improved method for the radiolabelling of [1-14C 00acyl-sphingosine-galactose-3-sulfate (sulfatide), requiring preparation of lysosulfatide (sulfogalactosyl-sphingosine) by alkaline hydrolysis of sulfatide and reacylation of the sphingosine amino group with a [1-14C]stearoyl chloride. We found that the yield of labeled sulfatide could be considerably increased using stringent chromatographic conditions for the preparation of lysosulfatide and strict anhydrous conditions for the formation of the acylchloride and its coupling to lysosulfatide. Radioscanning was used at different steps to check the purity of the labeled compounds. Radioscanning was also used to determine the formation of cerebroside when measuring cerebroside sulfate sulfatase activity and sulfatide metabolism in intact fibroblasts in controls and patients with metachromatic leukodystrophy. It could demonstrate and measure with accuracy the cerebroside sulfate storage characteristic of the disease.

In an experimental model of human African trypanosomiasis in sheep inoculated with Trypanosoma brucei brucei, we report an immunoglobulin reactivity towards central nervous system (CNS) glycolipids. Immunocharacterization of the glycolipid antigens was performed on thin-layer chromatography using peroxidase-labelled second antibody. An immunoreactivity against galactocerebroside antigens was observed in inoculated animals up to a dilution of 1:600 and was suppressed after immunoadsorption of sera on pure galactocerebrosides. As galactocerebroside antigen is responsible for demyelination in several experimental models, the relation between the important glycolipid immunoreactivity in inoculated sheep sera and the pathogenesis of CNS demyelination in African trypanosomiasis is suggested.

Incubation for 48 hours of C6 glioma cell cultures with 10(-4)M tricyclic antidepressant desipramine gave rise to a quantitative increase of total lipids and to qualitative modifications of glycosphinegolipids involving detection by thin-layer chromatography of spots migrating according to cerebroside and sulfatide and presence of an abnormal ganglioside pattern. These lipid modifications were associated with the appearance of stereospecific binding of opiates (dihydromorphine) with a dissociation constant of 30-60 nM. These results favor an important role of lipids in opioid receptor function.

Previous results indicate a dose-dependent decrease of lysosomal sphingomyelinase activity induced by tricyclic antidepressants in cell cultures. A possible association of this effect with the antidepressant-induced down-regulation of beta-adrenoceptors was postulated. We report here the determination of beta-adrenoceptor binding sites and lysosomal sphingomyelinase activity in the cerebral cortex of rats treated chronically with desipramine or with the potential antidepressant drug midalcipran (which is devoid of effect on beta-adrenoceptors). The effect of midalcipran on lysosomal sphingomyelinase activity was also determined on C6 glioma cells. In C6 glioma cells, midalcipran did not decrease sphingomyelinase activity, at variance with the enzymatic inhibition induced by desipramine (DMI). In the rat cerebral cortex, neither DMI nor midalcipran modified sphingomyelinase activity. In agreement with previously reported effects, DMI induced beta-adrenoceptor desensitization in the rat cerebral cortex, while midalcipran remained ineffective. Our results indicate that in the rat cerebral cortex, the activity of lysosomal sphingomyelinase is not modulated by chronic treatment with antidepressant drugs, whatever their effect on beta-adrenoceptor sites. Our results suggest that sphingomyelinase activity is not associated with the desensitization of beta-adrenoceptors, taken as an index of the therapeutic action of antidepressants. The results indicate that care should be taken when extrapolating to in vivo situations the conclusions derived from cell culture conditions.

The techniques described allow the quantitation of cholesterol, cerebrosides, sulfatides, ethanolamine phospholipids, phosphatidylcholine, -serine, -inositol, and gangliosides on 500 micrograms of lipid. Lipid extraction required sonication. Separation of the lipid classes was performed on TLC glass plates (10 x 10 cm) coated with silica gel HPTLC 60 F 254 Merck using one multiple two-dimensional chromatography. Most of the methods used for quantitation were standard methods that had been scaled down. The procedure was applied to study regional differences in the central nervous system, to analyze cell membranes or subcellular particles, or to analyze pathological biopsies in the central and peripheral nervous systems.

During the past 15 years, increasing studies have been devoted to glial cells, i.e. oligodendrocytes, astrocytes and microglial cells of the central nervous system. Although most of their functions remain mysterious, the concept of intracellular interactions between neurons and neuroglia becomes more and more substantiated. This review describes some aspects of phylogeny of glia, recent technical approaches to the study of these cells, their major morphological and biochemical characteristics, their maturation as well as their pathology.

We describe in this paper experiments in which oligodendrocytes (from newborn mouse, human embryonic brain, or isolated from adult rat brain) have been transplanted into the brain of the newborn mouse. Experimental conditions (Shiverer model) allowed the detection of myelin formed by transplanted oligodendrocytes into the Shiverer brain. The transplanted oligodendrocytes have been shown to survive, migrate over long distances and myelinate host axons. The maturation of transplanted oligodendrocytes depends upon the age of the brain tissue in which they differentiate.

A technique for the immunocharacterization of gangliosides on thin-layer plates using a peroxidase-labelled anti-Ig antibody is described. The technique uses plastic plates and does not necessitate any transfer of the antigen onto nitrocellulose for immunodetection. Being extremely sensitive, it permits the characterization of gangliosides which cannot be detected by classical densitometric techniques and allows the detection of gangliosides even in trace amounts in ganglioside mixtures. It appears to be useful for the screening of monoclonal antibodies because of its rapidity. Its specificity was found to be analogous to other immunological techniques such as complement fixation and agglutination.

There is often, in multiple sclerosis (MS) an intrathecal synthesis of immunoglobulin G (IgG) with an electrophoretic oligoclonal pattern. The target of those IgG, as well as their possible pathogenic role in the demyelinating process remain unknown and have led to many controversies. We have tested the hypothesis of an oligodendroglial target for those Ig, using a double labelling indirect immunofluorescent assay. Cerebrospinal fluid (CSF) Ig were collected from 28 MS patients (with either progressive or remitting-relapsing disease) and 25 patients with other neurological diseases. Ig binding has been tested on rat and human oligodendrocytes, isolated on a Percoll gradient and maintained 24 to 48 hours in culture. In our experimental conditions, we have never been able to detect any specific binding of MS CSF Ig on those oligodendrocytes, identified by double labelling immunofluorescence with an anti-galactocerebroside antibody.

This is a report of a case of the adult cerebral form of X-linked ALD. The 27-year-old patient presented with psychiatric disturbances. NMR was performed and compared to CT scan to define cerebral demyelination. The level of hexacosanoate was found to be increased in the patient's serum. Biochemical analysis of the patient's mother's serum and cultured fibroblasts and of serum samples from 10 other members of the family who could have been carriers of this X-linked disease, produced negative results. Hence, it is most likely that this case has occurred sporadically. HLA determination revealed the DR2 antigen which is often associated with multiple sclerosis.

We report here the results of a simple and reproducible technique which can be used in semi-routine analysis of peripheral nerve biopsy specimens, so as to have a quantitative analysis of the major lipid classes, i.e. cholesterol, cerebrosides, ethanolamine phospholipids, phosphatidyl-choline, phosphatidyl-serine + phosphatidylinositol, sphingomyelin and gangliosides. Glycolipid hexoses, cholesterol and total phospholipids have been compared in different age groups. Although all lipid classes increased from the younger to the older age group, the molar ratio of cholesterol to phospholipid differed less than the glycolipid to phospholipid ratio. Both increased significantly, even between age group 10--16 and older patients (36, 54, 61, 68, 72 and 73 years old). Although individual variations in lipid content are noteworthy, it must be emphasized that evolution with age of the lipid composition must be taken into account. Furthermore, this study confirms and extends earlier findings of increased ganglioside levels in some cases of peripheral neuropathies observed during perhexiline maleate therapy where characteristic lipid-like polymorphous inclusions have been demonstrated.

Because of the role they play in the physiopathology of peripheral neuropathies, Schwann cells have been the subject of numerous studies for some ten years. Schwann cells originate in the ectoderm. They migrate along the myelinated and the unmyelinated axons of peripheral nerves, and lie on a basal lamina. They are responsible for the myelination of peripheral nerves; whether the Schwann cell does or does not form a myelin sheath is determined by the type of axon with which it associates. Recent techniques, such as chimaeric quail-chick embryos, biochemical analysis of human peripheral nerve biopsies, Schwann-cell cultures, nerve grafts, mouse mutants, have permitted some progress. The biochemical composition of peripheral myelin is almost completely known. In vitro, Schwann cells can synthesize myelin-specific molecules. Interactions between axons, Schwann-cells and extra-cellular space have been observed.

Phenothiazines and tricyclic antidepressants, when added to culture medium, gave rise in several types of cells (C6 rat glioma cells and human fibroblasts), to a decrease in lysosomal sphingomyelinase activity. The effect of chlorpromazine and desipramine was dose dependent, and was observed after 3 hours of incubation with the drugs at concentrations ranging between 1 and 10 microM. In C6 glioma cell cultures, the decrease in sphingomyelinase activity was related to the clinical effectiveness of phenothiazines, tricyclic antidepressants and derivatives. Incorporation of (choline-14C) sphingomyelin showed that the metabolic pathway implying the synthesis of phosphatidylcholine from the hydrolysis of sphingomyelin and/or transfer of phosphorylcholine to phosphatidylcholine was also partially reduced.