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Nonketotic hyperglycinemia is a life-threatening disorder in neonates characterized by a deficiency of the glycine cleavage system. We report on four cases of the neonatal form of the disease, which were investigated by in vitro(1)H magnetic resonance spectroscopy of blood and cerebrospinal fluid, and in vivo(1)H magnetic resonance spectroscopy of brain. The existence of glycine disposal pathways leading to an increase in lactate in fluids and creatine in fluids and brain was demonstrated. This is the first observation of elevated creatine in brain in nonketotic hyperglycinemia. A recurrent decrease of glutamine and citrate was observed in cerebrospinal fluid, which might be related to abnormal glutamine metabolism in brain. Finally, the cerebral N-acetylaspartate to myo-inositol-glycine ratio was identified as a prognostic indicator of the disease.

Background Objectives Neurological manifestations involving the central and the peripheral nervous systems (CNS, PNS) are observed in 10%-32% of patients with primary Sjogren’s syndrome (pSS). If the lesions of the PNS have been perfectly described, data on CNS involvement in pSS, as for it, is controversial with regard in significance and aetiology. On occasion of an exceptional supra-nuclear ophtalmoplegia during pSS, we discuss relevance of CNS involvement in pSS. Methods Results A 61 year-old-woman encompassed several episodes of neurologic involvement resolving completely without any treatment: twice it consisted of mied nerves involvement (dysphagia) and dysaesthesia in the trigeminal territories and four times of supra-nuclear ophtalmoplegia with typical palsy of volontary lateral and vertical gaze compensated for oculo-cephalics reflexes. Repeated cerebral investigations excluded multiple sclerosis and vascular lesions. The absence of hypertonia, akinesia, or frontal syndrome associated to opthtalmoplegia, despite several years duration, reduces the probability of a Steele-Richardson disease. Neurologic signs onset began sixteen years before the diagnosis of pSS (grade III histologic lesions on minor salivary gland biopsy). Biochemical, immunologic and histological investigations did not reveal any other connective tissue disorders. This is the first case of supra-nuclear ophtalmoplegia developped in such a context. Oculo-motors troubles like nystagmus, ocular palsy, cerebellar syndrome and even internuclear ophtalmoplegia has been describe during pSS. Internuclear ophtalmoplegia is provoked by intra-axial lesions within the higher part of the cerebral trunk, above mesencephalic oculo-motor centres; however, a supra-nuclear lesion during pSS has never been reported so far. Through a literature review, we discuss relevance, aetiology and treatment of CNS involvement in pSS. Data are imprecise and even contradictory. Frequency of CNS involvement in pSS could vary from 0% to 25% and might display various patterns: focal or multi focal lesions entailing encephalon, cerebral trunk, cerebellum or medulla, but also more diffuse processes as an aseptic meningo-encephalitis or as a cognitive impairment. It’s pathogenesis is poorly understood. Two mechanisms have been proposed: the first being of an ischaemic nature resulting from a vasculitis of small brain vessels, the second through an autoimmune response (humoral by anti-neuronal antibodies or cytotoxic). There is no clear consensus concerning the treatment of neurological complications of pSS. Corticosteroids are usually initiated first; immuno-suppressive agents may be necessary in the absence of improvement. Conclusion A supranuclear ophtalmoplegia can be observed in pSS; it reinforces the thesis of a CNS involvement in this connective disease, in so far such a characteristic symptom cannot be explained by a Steele-Richarson disease, a multiple sclerosis or vascular lesions. Be aware of CNS involvement in pSS would leed to realise a minor salivary gland biopsy that is the only exam useful to establish the diagnosis.

In the last 6 months, 2 patients have been admitted to our stroke center for ischemic stroke related to internal carotid artery (ICA) dissection that occurred during intensive video sports game practice with Wii® gaming system, the new generation of interactive wireless gaming console. Wii® has been widely distributed only since December 2006 and an increasing number of associated-injury cases have been reported in the literature since June 2007 (severe osteoarticular injuries involving shoulder or knee and hemothorax).1–4 These cases illustrate the intensity of some efforts performed during the practice of these video sports games. ### Case presentation. Our first case is a previously healthy 47-year-old woman who developed stroke due to ICA and middle cerebral artery (MCA) occlusion related to proximal ICA dissection during intense sports video game practice with the Wii® console system. She played a tennis video game for 3 hours consecutively, during which she experienced sudden severe left neck pain and unusual headache followed a few minutes later by right acute hemiplegia and aphasia (NIH Stroke Scale score = 15). In spite of partial MCA recanalization after intravenous thrombolysis (IVT), the patient was still dependent (modified …

A 60-year-old patient is presented who developed a stroke related to a bilateral internal carotid artery dissection due to elongated styloid processes and intense jerky head movements during unwonted shaking dance. The association between elongated styloid process and cervicofacial pain is well known as Eagle’s syndrome but its association with stroke is exceptional. To our knowledge, this case is the first observation of bilateral carotid artery dissection related to elongated styloid processes and demonstrates that cervical CT angioscan is a very efficient non-invasive method of diagnosing this rare condition. A previously healthy 60-year-old man, without vascular risk factors, presented with a sudden acute left hemiplegia after a 2 day history of right severe fronto-orbital headache following an intense shaking dance “like an invertebrate as his wife said”. Physical examination showed confusion, hemiplegia, hemiataxia and lateral hemianopia on the left side (NIHSS = 13). There was also a complete right …

A new clinicopathological case of Devic's neuromyelitis optica, including unusual predominant clinical features (fatal dysautonomia) is described herein: pathological examination showed extensive and severe demyelination mainly involving the optic nerves, the medulla, and spinal cord, which was particularly pronounced in the thoracic segments, and thus explained the unusual vegetative symptomatology. In a review of 45 clinicopathological cases described in the literature as Devic's disease (DD), it turned out that only 22 cases, including the patient described here, fulfilled the recently defined diagnostic criteria [Devic 1980]. Among the other 23 cases, 15 did not fulfill the criteria because of the occurrence of relapses, 3 others had 2 separate pathological locations within the spinal cord, and the remaining 5 showed evidence that a disease other than DD was involved. Among the 22 cases which were definitely taken to be DD, the mean age at clinical onset was 39 years (+/- 14); it was characterized by acute bilateral visual loss and transversal myelitis which gradually led either to death or to partial or complete recovery. The pathological lesions, which mostly were located along the optic tracts and the spinal cord, were characterized by demyelination with inflammation and necrosis; in some cases the pathological process diffused into the medulla (8/22 cases) or the whole brainstem (4/22 cases). The cavitation of the spinal cord was not a key feature of the diagnosis, since it was observed on only 9/22 cases. Devic's neuromyelitis optica may be a separate nosological entity which differs from multiple sclerosis.

A number of previously unidentified 1H NMR signals detected in CSF spectra of patients with various neurological and metabolic diseases are assigned to metabolites, drugs and drug excipients. Two-dimensional 1H NMR spectroscopy (COSY and J-resolved) is employed to resolve resonances which are hidden by superimposed peaks in one-dimensional spectra. Assignments obtained by making use of 2-D techniques, and of a 1-D 1H NMR data base created for ca. 150 authentic compounds, enable us to clarify the nature of complex signal patterns found in crowded spectral regions of CSF such as the aliphatic methyl region at ca. 1.0 ppm.

Proton MRS has proved useful in the early diagnosis of HIV-related encephalopathy. The modifications of brain metabolism in HIV-related encephalopathy can be classified according to different metabolic patterns (Vion-Dury J et al. CR Acad Sci 1994;317:833-840). The present study describes the relative occurrence of these patterns and evaluates their evolution under zidovudine treatment. We have examined 112 HIV patients--35 neuroasymptomatic patients and 77 patients with ADC (AIDS dementia complex)--with localized proton MRS, using the PRESS 135-msec sequence. We have found the same metabolic modifications in N-acetylaspartate and choline-containing compounds as described in the literature. In addition, 14% of HIV patients with normal MRI displayed abnormal MRS, whatever their neurological status. The MRS-added diagnostic value in neuroasymptomatic patients reaches 30 %. The occurrence of undifferentiated (modification of NAA/Cho ratio only) and Cho (mainly an increase in choline signal) patterns is not significantly different in neuroasymptomatic and ADC patients. The NAA pattern (mainly a significant loss of NAA) is more frequent in ADC patients. Only ADC patients display the double pattern (with a significant increase in choline signal and a significant loss of NAA). Quantitated cerebral atrophy (bifrontal ratio) is related to the occurrence of NAA loss (in NAA and double patterns). An MRS follow-up study of 11 HIV patients showed that the clinical outcome was favorable after a 1000-mg/day zidovudine treatment in patients displaying an NAA pattern whereas this treatment had no effect on the patients displaying the Cho pattern. Consequently, MRS appears to be of great interest in predicting responsiveness to antiretroviral drugs and detecting early any resistance to treatment.

The incidence of neurosyphilis has been increasing since AIDS has appeared but acute gummatous necrotizing progression is so far exceptional. We report a second case of "quaternary neurosyphilis" in a 29-year-old patient without serologic nor CT scan evidence of treponema. Diagnosing neurosyphilis is particularly difficult in HIV-1 infected patients, specially in spirochetes-poor injuries.

We have analyzed the cerebrospinal fluid (CSF) of 19 patients with multiple sclerosis (MS), 12 patients with degenerative dementia and 17 control patients using in vitro high resolution proton magnetic resonance spectroscopy (MRS) at 400 MHz. The CSF metabolic profile is slightly modified in MS patients (increased lactate and fructose concentrations, decreased creatinine and phenylalanine concentrations) and is not correlated with the intensity of the intrathecal inflammation. Proton MRS of CSF does not differentiate relapsing-remitting MS and primary progressive MS. We have not detected any specific abnormal resonance in native or lyophilized CSF. The CSF metabolic profile of demented patients is much more altered (increased concentration of lactate, pyruvate, alanine, lysine, valine, leucine-isoleucine, tyrosine, glutamine) and is in agreement with a brain oxidative metabolism impairment as already described in Alzheimer's disease. Unassigned abnormal but non specific or constant resonances have been detected on MR spectra of demented patients. CSF inositol concentration is also increased in the CSF of patients with Alzheimer's disease. In vitro high resolution proton MRS of the CSF constitutes a new and original way to explore CSF for the differential and/or early diagnosis of dementias, as a complement to in vivo proton cerebral MRS.

Human immunodeficiency virus (HIV) infection as seen in Europe and the United States has predominantly been contracted through male homosexual sex or intravenous drug abuse. In infected subjects, the brain is frequently affected both clinically and neuropathologically. The aim of this multicenter study has been to evaluate the value of single-voxel proton magnetic resonance spectroscopy (MRS) in the assessment of the neurological complications of acquired immunodeficiency syndrome (AIDS). MRS (voxel size = 8 ml, TR/TE = 1600/135 msec) was performed in 137 HIV-1-seropositive patients and 64 healthy controls without risk factors at three clinical MR sites operating at 1.5 T. The first result of this multicenter trial is that good reproducibility of results among participating sites was found. This demonstrates the reliability and robustness of MRS in the study of in vivo brain metabolism. In HIV patients, there was no significant correlation between metabolite ratios of brain detected by MRS and CDC grouping of patients or CD4 count. In contrast, the variations of brain metabolite ratios (NA/Cr, NA/Cho, and Cho/Cr) were related to the occurrence of encephalopathy, brain atrophy, or diffuse white matter lesions. There was no significant difference in brain metabolites between male homosexual AIDS patients and male intravenous drug user AIDS patients, whatever their neurological status (neurosymptomatic or neuroasymptomatic). Thus, the mode of transmission of HIV infection does not appear to affect the cerebral changes observed in the proton spectra from AIDS patients. Because of its ease of implementation and high information content, single-voxel proton MRS is likely to play a significant role in the evaluation of HIV-related encephalopathies.

We have performed localised proton magnetic resonance spectroscopy (MRS) of the brain on four patients with X-linked adrenoleukodystrophy (X-ALD). The spectrum is characterised at the beginning of the disease by a decrease in N-acetylaspartate and phosphocreatine-creatine content. Choline is strongly increased, and lactate can be detected in some cases. A proton signal from the CH2 groups borne by free intracellular very long chain fatty acids can also be observed. Later in the disease, the levels of all metabolites, in particular NAA, decrease significantly. The progression of neurometabolism documented by MRS correlates well with MRI and clinical progression on follow-up study. In one case, the metabolic profile recorded by proton MRS was abnormal before any change occurred on MRI. Proton MRS of the brain might be the method of choice for monitoring patients with X-ALD, to screen presumed cases and to study the effects of treatment.

We have examined 9 healthy volunteers and 63 HIV-patients (16 asymptomatic patients and 47 patients with clinical AIDS-dementia complex, ADC) by magnetic resonance spectroscopy (MRS) and imaging (MRI) on a Siemens Magnetom SP63 (1.5 T). Proton MRS of the brain was performed at 63 MHz using the PRESS sequence (echo time = 135 ms, TR = 1.6 s). Four main results have been found: (1) HIV-related encephalopathy induces significant modifications of brain metabolism analyzed by MRS and the most sensitive metabolic parameter is the N-acetyl-aspartate/Choline ratio, (2) the correlation between MRS and MRI is good in 75% of patients, (3) in 4 of the 16 neuro-asymptomatic patients (i.e. 25%) a metabolic encephalopathy was found while MRI was still normal, and (4) MR spectra describe 3 different pathological metabolic patterns in the brain of HIV patients. Two patterns might correspond to the two entities of HIV-induced lesions i.e. HIV encephalitis and HIV-related progressive leukoencephalopathy.

We report a new case of Marchiafava-Bignami disease with favourable outcome. This case is particular on several scores. The interhemispheric disconnection syndrome was associated with Balint's syndrome, and this had apparently never been reported in this context previously. Despite the intensity and diffusion of white matter lesions in both hemispheres, and in the absence of vitamin treatment, the clinical and neuroradiological (CT, MRI) improvement occurred early and rapidly. This course, similar to that of toxic drug withdrawal, suggested that this was not a process of vitamin deficiency. Data from the literature indicate that a wide extension of corpus callosum lesions to the semi-ovale centre has a poor vital and functional prognosis. Our case shows that this is not always correct and that the appearance of intralesional necrosis and cavitation is not the rule. We consider that the most reliable factor of poor prognosis seems to be an initial coma.

Localised proton magnetic resonance (MR) spectroscopy of the human brain is a new non-invasive technique which allows the detection of cerebral intermediary and oxidative metabolites (Hanstock et al, 1988). MR spectra can be obtained by using either single-volume acquisition sequences (such as STEAM, ISIS, VSE sequences) or multiple volume acquisition sequences such as the spectroscopic imaging (SI) technique which provides a display of metabolite maps (for a review, see Confort-Gouny et al., 1992a).

We studied both cerebrospinal fluid (CSF) and serum of 11 patients suffering from Huntington's disease (HD) and 12 control subjects by combining high resolution proton NMR spectroscopy and HPLC. NMR spectroscopy analysis of the CSF shows a significant increase (60%) in pyruvate concentration in HD patients. No unexpected molecules were detected. Glutamate, glutamine, aspartate, proline and GABA levels were found unchanged in the CSF of HD patients, using HPLC analysis. Conversely, a significant increase (30%) in the CSF level of glycine was detected. These observations are in agreement with the metabolic hypothesis of HD physiopathogenesis. In addition, the protocol combining NMR spectroscopy and HPLC provides a straightforward evaluation of brain metabolic status and blood-brain-barrier function.

Three hours after sniffing a dose of heroin, a 30-year old man developed right hemiplegia with aphasia. Magnetic resonance imaging of the brain showed an infarct in the territory of the left anterior choroid artery. Cerebral vascular accidents occurring as complications of heroin addiction are rare: a review of the literature yielded only 13 documented cases. The main characteristics of these strokes are analysed and their pathogenetic mechanisms (immuno-allergic vasculitis, vascular spasm) are discussed.

Proton localized Magnetic Resonance Spectroscopy (MRS) of the brain allows the non invasive detection of intracellular cerebral metabolites. Localized MRS has been performed using short stimulated-echo times in various neurological diseases including stroke, multiple sclerosis, and AIDS-related leukoencephalopathies. Principal component analysis (PCA) was used to determine the critical parameters defining the metabolic profile of normal and diseased brain. PCA clearly differentiates the demyelinating processes from ischaemic lesions and leukoencephalopathies. Localized MRS of the brain appears growingly as a tool of choice to discriminate, quantitate and assess cerebral metabolic damage in patients with neurological disorders.

A case of bacterial endocarditis complicated by paralytic pontine exotropia is reported. Magnetic resonance imaging clearly showed a rostral lesion of the paramedial pontine reticular formation and the medial longitudinal fasciculus. The occurrence of paralytic pontine exotropia is suggestive of ischaemia, and patients with this so-called "one-and-a-half syndrome" associated with signs of infection should be investigated for endocarditis.

The authors report two cases of hemichorea-hemiballism revealing a toxoplasmic abscess in the subthalamic nucleus during AIDS. Despite the great frequency of this opportunistic infection such cases are exceptional. This rarity seems to be explained by the frequent association of other lesions of the basal ganglia which may prevent the movement disorders. Nevertheless an hemichorea-hemiballism in young people must suggest a cerebral toxoplasmosis. Finally a symptomatic treatment is often necessary; in these cases the use of sodium valproate must be considered, this drug being able to induce a clinical improvement.

The principles of dynamic light scattering (DLS), applied to size analysis of submicron particles suspended in liquid, are reviewed. A comparison is made between two methods of inversion of the autocorrelation function data (cumulants analysis and Laplace transform inversion); choice of the appropriate method depends on the complexity of the underlying particle size distribution (PSD). Representative results are discussed and illustrate the current state-of-the-art of particle size analysis by DLS. Examples include polymer latexes, oil/water emulsions, surfactant micelles and small proteins.

High resolution proton nuclear magnetic resonance (NMR) spectroscopy is a new analytical technique which allows to readily identify and quantitate a variety of key metabolites in cerebrospinal fluid (CSF) in relation to normal and pathological brain activity. Proton NMR spectroscopy can be performed on native CSF, with or without addition of exchange reagent (NH4Cl). The analysis of native CSF provides qualitative information (identification) of metabolites or xenobiotics present in the fluid. Alternately, CSF can be lyophilized and dissolved in deuterated water. This concentration offers 2 advantages: additional compounds are detected and a precise quantification of all CSF metabolites can be obtained. Both protocols require a very small volume of CFS (1-2 ml). The high informational content available on the NMR spectra of CSF, the ease-of-use of NMR spectroscopy and its cost effectiveness concur to predict that this analytical approach will keep developing to completement the array of existing tests which are already routinely performed on CSF.

Indoor radon concentration in Bologna was monitored using two types of detectors with different characteristics. The measurements gave consistent results. It has been verified that the radon concentration in Bologna is well below the ‘attention’ level given in the scientific literature.

A theoretical model describing the association of ionic surfactants into rod-shaped micelles is combined with an approximate formula for the viscosity increase induced by rod-shaped aggregates. It is shown that most of the thermodynamic parameters of the association model can be obtained from viscosity measurements. The approach is applied to micellar solutions of hexadecylpyridinium salts. The pronounced effect of counter-ion concentration on the growth of rod-shaped micelles can be attributed to a slightly higher degree of counter-ion association in the cylindrical part than in the end portions. An attempt is made to explain the finding that the degree of counter-ion association is virtually independent of counter-ion concentration.

Three cases of chronic subdural hematoma (CSDH) revealed by transient neurological accidents are reported. Although well-known this condition is rare: 1 to 9 p. 100 of CSDHs. Questioning may bring out a history of cranial injury and headache, even minor ones, which are unusual in transient ischemic accidents (TIA). Transient phenomena, such as motor aphasia or speech interruption, point to the diagnosis, especially in male patients over 60 years of age. The finding at electroencephalography of a delta activity more than 48 hours after a TND should exclude the diagnosis of TIA until a CT scan is performed. Since the causes of neurological deficits regressing within less than 24 hours may be ischemia as well a hemorrhage or tumour, the term of transient neurological accident (TNA) should preferably be used, and an emergency CT scan should be performed for diagnostic and therapeutic purposes. Owing to the possibility of another concomitant cause of TNA, the finding of a subdural haematoma should not deter from pursuing cardiovascular examinations. The mechanism of TNA probably involves a vascular factor, as suggested by I-123 IMP cerebral SPECT which shows an intercritical decrease in cerebral blood flow and/or an epileptic factor.

Objectifs pedagogiques Comprendre les bases physiques de la spectroscopie par resonance magnetique (SRM). Connaitre les principales indications de la SRM en pratique clinique. Savoir realiser un examen SRM. Connaitre l’aspect SRM des principales affections neurologiques.

A 27 year-old man had a demyelinating neuropathy associated with an IgG lambda monoclonal protein secondary to a vertebral solitary plasmocytoma. An improvement was obtained with radiotherapy and chemotherapy. 15 years later the patient had a cranial solitary plasmocytoma with seizures, deterioration of intellect, postural tremor and a POEMS syndrome:polyneuropathy, splenomegaly, gynecomastia, monoclonal protein (IgG lambda), skin changes.

The effective hydrodynamic radii of micelles of myristyltrimethylammonium bromide have been measured as a function of pressure using the technique of laser light scattering spectroscopy. Micellar size in high salt concentrations is observed to shrink or grow markedly in the pressure range 1–3000 bar and at temperatures between 12 and 41°C.

Bioassays, including immunoassays, enzyme assays, and assays using enzyme electrodes, and nucleic acid hybridization probes have been the subject of considerable industrial and academic research. New bioassay methods have applications in the medical, chemical, pharmaceutical, and food products industries. Recent US patents and scientific literature on a variety of new bioassay methods are surveyed. A description of these patents and a list of references are given.

Variation in vegetative and reproductive growth patterns leading to summer flowering and fruiting was evaluated in everbearing and in representative Junebearing strawberry (Fragaria × ananassa Duch) clones under simulated summer conditions in the greenhouse and in growth chambers. Summer flowering intensity, periodicity, fruit set, and maturation were related to plant architectural parameters such as crown, leaf and runner production, number of meristems produced and differentiated, leaf areas and petiole length, plant volume, and dry weight allocation patterns. A continuum of growth habits and flowering behavior precluded rigid classification of summer flowering response, but useful arbitrary distinctions were made on the bases of: photoperiod reaction into short-day (Junebearing) vs. weak, intermediate, or strong day-neutrals; or summer fruit expectation into essentially none (Junebearing) vs. sporadic or consistent everbearers. Critical criteria for separating Junebearers from everbearers include degree of summer flowering and fruiting (fresh or dry weight basis), plant volume (and its components, petiole length, and average leaf area), and the dry weight allocation ratios—root : shoot and reproductive : vegetative. Everbearing (or day-neutral) types could be distinguished by plant volume and composition differences (size, number, and percentage of developed meristems, leaf area ratio, reproductive dry weight, etc.) and continuity of individual plant flowering. Three basic models of shoot growth and inflorescence positioning are proposed from evidence for alternative modes of flowering site generation in everbearing strawberries.