Large field-of-view phase and fluorescence mesoscope with microscopic resolution.

Phase and fluorescence are complementary contrasts that are commonly used in biology. However, the coupling of these two modalities is traditionally limited to high magnification and complex imaging systems. For statistical studies of biological populations, a large field-of-view is required.

Hemolysis by surfactants--A review.

An overview of the use of surfactants for erythrocyte lysis and their cell membrane action mechanisms is given. Erythrocyte membrane characteristics and its association with the cell cytoskeleton are presented in order to complete understanding of the erythrocyte membrane distortion. Cell homeostasis disturbances caused by surfactants might induce changes starting from shape modification to cell lysis.

A low cost and high throughput magnetic bead-based immuno-agglutination assay in confined droplets.

Although passive immuno-agglutination assays consist of one step and simple procedures, they are usually not adapted for high throughput analyses and they require expensive and bulky equipment for quantitation steps. Here we demonstrate a low cost, multimodal and high throughput immuno-agglutination assay that relies on a combination of magnetic beads (MBs), droplets microfluidics and magnetic tweezers. Antibody coated MBs were used as a capture support in the homogeneous phase.

Relationships between gray matter metabolic abnormalities and white matter inflammation in patients at the very early stage of MS : a MRSI study.

Proton magnetic resonance spectroscopic imaging ((1)H-MRSI) was used to study metabolic abnormalities inside the gray matter (GM) during or distant to white matter (WM) inflammatory processes reflected by T(1) gadolinium-enhancing lesions in patients at the very early stage of multiple sclerosis (MS). The spectroscopic examination was performed in the axial plane using a home-designed acquisition-weighted, hamming shape, 2D-SE pulse sequence (TE = 135 ms; TR = 1,600 ms). Bilateral thalami and the medial occipital cortex were explored in 35 patients (15 with and 20 without T(1)-Gd enhancing lesions) with clinically isolated syndrome suggestive of MS and in 30 controls.

Onset and underpinnings of white matter atrophy at the very early stage of multiple sclerosis--a two-year longitudinal MRI/MRSI study of corpus callosum.

Background: Atrophy of corpus callosum (CC), a white matter structure linking the two hemispheres, is commonly observed in multiple sclerosis (MS). However, the occurrence and processes leading to this alteration are not yet determined.

Goal And Methods: To better characterize the onset and progression of CC atrophy from the early stage of MS, we performed a two-year follow-up magnetic resonance imaging/magnetic resonance spectroscopic imaging (MRI/MRSI) exploration of CC in 24 patients with clinically isolated syndrome.

End-of-dose akinesia after a single intravenous infusion of the dopaminergic agonist piribedil in Parkinson's disease patients: a pharmacokinetic/pharmacodynamic, randomized, double-blind study.

This randomized, double-blind trial was designed to define the possible relationship between piribedil plasma concentrations and the decrease of the Unified Parkinson's Disease Rating Scale (UPDRS) motor score or the switch from off to on state after single intravenous infusion. Ten fluctuating patients with idiopathic Parkinson's disease (PD) received escalating doses of piribedil (2-16 mg) and placebo. Starting from 2 mg, piribedil was effective in reducing the motor deficit (UPDRS, motor score) including akinesia at the first evaluation time point of 15 minutes, and in reversing off state of 7 of 10 patients.

Functional MRI study of PASAT in normal subjects.

The paced auditory serial addition test (PASAT) is routinely used to evaluate the cognitive part of the multiple sclerosis functional composite (MSFC) score, the new reference index of patient disability. PASAT is sensitive to subtle cognitive impairment related to MS, although the cognitive components of this test still remain unclear. In order to better characterize brain systems involved during this complex task, functional magnetic resonance imaging (fMRI) experiments were conducted during PASAT in a population of ten normal subjects.

Local tissue damage assessed with statistical mapping analysis of brain magnetization transfer ratio: relationship with functional status of patients in the earliest stage of multiple sclerosis.

Background And Purpose: In the early stage of Multiple Sclerosis (MS), conventional MR imaging parameters such as T2 lesion load fail to explain the clinical status of patients. In the present work, we aimed to determine the ability of magnification transfer imaging to better reflect the relationship between local tissue damage and functional status of MS patients.

Methods: We performed a comparative statistical mapping analysis on brain tissue magnetization transfer ratio (MTR) data measured in 18 patients with clinically isolated syndrome suggestive of MS (CISSMS) and 18 matched control subjects.

Magnetic resonance study of the influence of tissue damage and cortical reorganization on PASAT performance at the earliest stage of multiple sclerosis.

We sought to determine the influence of tissue damage and the potential impact of cortical reorganization on the performance to the Paced Auditory Serial Addition Test (PASAT) in patients at the earliest stage of multiple sclerosis (MS). Magnetization transfer ratio (MTR) imaging and functional magnetic resonance imaging (fMRI) experiments using PASAT as paradigm were carried out in 18 patients with clinically isolated syndrome suggestive of MS (CISSMS) compared to 18 controls. MTR histogram analyses showed structural abnormalities in patients involving the normal-appearing white matter (NAWM) but also the gray matter (GM).

Voxel-based analysis of MTR images: a method to locate gray matter abnormalities in patients at the earliest stage of multiple sclerosis.

Purpose: To determine whether voxel-based analysis of magnetization transfer ratio (MTR) maps can provide evidence of a coherent pattern of gray matter (GM) macroscopic and microscopic tissue damage in patients at the earliest stage of multiple sclerosis (MS).

Materials And Methods: We acquired GM MTR maps in 18 patients with clinically isolated syndrome suggestive of MS (CISSMS), and 18 sex- and age-matched healthy controls. We evaluated the clinical status of the patients using the MS functional composite score and the expanded disability status scale.

Compensatory cortical activation observed by fMRI during a cognitive task at the earliest stage of MS.

Recent functional magnetic resonance imaging (fMRI) studies have suggested that functional cortical changes seen in patients with early relapsing-remitting multiple sclerosis (MS) can have an adaptive role to limit the clinical impact of tissue injury. To determine whether cortical reorganization occurs during high cognitive processes at the earliest stage of multiple sclerosis (MS), we performed an fMRI experiment using the conventional Paced Auditory Serial Addition Test (PASAT) as paradigm in a population of ten patients with clinically isolated syndrome suggestive of multiple sclerosis (CISSMS). At the time of the fMRI exploration, mean disease duration was 6.

[Characterization of gestural disorders in primary progressive apraxia: diagnostic and nosographic contribution].

Five cases are reported of patients with so-called primary progressive apraxia, defined as a slowly worsening disturbance of gestural abilities, without other major cognitive changes during a long period, in relation to degenerative cortical atrophy. All five cases, as other cases in the literature, share the following common features: 1) asymmetrical onset of upper limb clumsiness, more often involving the left side, later involving the contralateral side and lower limbs; 2) after a variable delay, the occurrence of symptoms suggesting subcortical involvement (akinesia, limb stiffness, various kinds of movement disorders, dystonia, paresis of vertical gaze); 3) diffuse cortical atrophy typically more pronounced in the superior parietal cortex opposite to the first side affected. The unusual nature of apraxia in all these cases is pointed out and referred to as Luria's "kinesthaesic apraxia", ascribed to a loss of "selectivity" of distal elementary movements.

[Systematized cavernous angiomatosis with multiple cerebral and cutaneous localizations].

A 45 year-old woman with no history of familial disease presented with multiple cutaneous and cerebral cavernous angiomas. The diagnosis rested on biopsy for cutaneous angiomas and on MRI for cerebral angiomas. The clinical manifestations of cerebral angiomas were headaches and a cerebellar syndrome, the latter most probably due to progressive growth of cerebellar angiomas.

[Carotid artery occlusion disclosed by cerebral ischemia. Lesional, etiologic and developing aspects].

The authors report on a series of 100 patients, who underwent an ischemic cerebrovascular accident (CVA) (8 transient attacks, 15 minor CVAs and 77 completed strokes) which revealed internal carotid artery occlusion (unilateral in 93 cases and bilateral in 7), proven by ultrasonography and/or angiography. The computerized tomography scan was normal in 8 cases. The middle cerebral artery territory was involved in 84 patients (isolated or associated (25 patients) with another site), whereas an isolated watershed infarction was the only lesion in the other 8 patients.

Age-related changes in aphasia type and stroke location.

Two-hundred consecutive CT scans of patients with an infarction in the territory of the middle cerebral artery (MCA) were examined for evaluation of a possible relationship between age and stroke location. Two distinct procedures, one evaluating the incidence of four areas within the MCA territory and the other measuring some quantified parameters, were used. Statistical studies failed to show any significant correlation between these parameters and the age of patients.

[In vivo location of the cortical language areas (correlation between anatomy, x-ray computed tomography and magnetic resonance imaging)].

Cortical language areas were identified by CT scan or NMR imaging, using planes of horizontal sections parallel to the orbitomeatal plane and therefore indirectly to the bicommissural plane. Sections 45 and 50 mm above the bicommissural plane pass electively through temporal structures i.e.

[Persistent neurological syndrome after treatment with lithium salts. Toxicity of the lithium-neuroleptic combination?].

In 2 patients receiving a long-term lithium carbonate therapy, persistent cerebellar, pyramidal, and extrapyramidal signs were observed, following a febrile pulmonary event. The mechanism of these disturbances is discussed, emphasizing the lithium-neuroleptics interaction as well as the possible role of hyperthermia.

[Alexander's disease in an adult].

A 34-year-old man developed cerebellar symptoms, palatal myoclonus and spastic paraparesis progressing over several months. During this period, acute respiratory failure occurred in two instances with evidence of central chronic hypoventilation. CT scan showed enlargement of the frontal horns and posterior fossa cisterns.

[Neuroendocrine sarcoidosis: a case].

The authors report a case of neuro-endocrine sarcoidosis, associating panhypopituitarism , diabetes insipidus, and involvement of the optic chiasma with behavioural changes, chronic meningitis and a diffuse pyramidal syndrome. The diagnosis was suggested by the presence of mediastinal lymphadenopathy and confirmed during a surgical procedure to conserve the optic nerves. The clinical course on corticosteroids was unfavourable because of iatrogenic cushing' syndrome and steroid dependence .

[Behavior and mental activity disorders after carbon monoxide poisoning. Bilateral pallidal lesions].

Two patients who had suffered severe carbon monoxide intoxication showed lasting neuropsychologic sequelae: 1) deep inertia involving the whole behaviour and expressed by an almost complete lack of activity if not induced by someone else; a mental gap when the patients were left to themselves and a tendency to give up the mental activity when stimuli ceased; an apparent affective indifference connected with a lack of spontaneous expression of the affects; 2) pseudo-obsessionnal activities: coprolalia with sexual themes in one patient, obsessive collecting and tidying up activities in the other one. Neurologic examination was normal, particularly no parkinsonian syndrome was present. CT scans showed bilateral pallidal low density areas.

[Development of aphasic symptomatology with age. Discussion apropos of an anatomo-clinical case].

Clinical data suggesting that aphasic semeiology undergo some evolution with age are summarized. Three kinds of hypotheses may account for this evolution: (1) a possible evolution with age of the site and extent of ischaemic lesions: (2) an evolution according to age of brain functional organization for language; and (3) evolution with age of psychological and/or social aspects of individuals in whom aphasia occurs. These hypotheses are discussed in the light of a clinico-pathological case of Wernicke's aphasia with logorrheic jargon due to an infarct involving both anterior and posterior parts of the left cortical speech area.

Crossed aphasia in dextrals: a case report with special reference to site of lesion.

A strictly right-handed man showed aphasia and left hemiplegia following a deep infarct of the right hemisphere. Aphasic semeiology was characterized by an oral and written jargon while comprehension was almost intact. Several hypotheses previously put forward fail to account for the patient's aphasia.