Metabolic and neurological consequences of the treatment with polyphenols: a systematic review in rodent models of noncommunicable diseases.

BACKGROUND: Noncommunicable diseases (NCDs) lead to drastic metabolic alterations with associated energy balance and body weight changes, two related physiological processes regulated by the brain. Polyphenol-based treatments for NCDs have emerged as a promising therapy, which seems to involve the energy balance modulation. However, it remains unclear what the most effective polyphenols-based treatment is to attenuate adverse effects in the energy balance of NCDs. OBJECTIVES: This systematic review aimed to evaluate the literature on the metabolic and neurological effects of polyphenols-based treatment in rodent models of NCDs. METHODS: Literature search was carried out in the following databases: CINAHL, Medline/PubMed, SCOPUS, and Web of Science. For title and abstract screening, original papers with polyphenols exposure in rodents were selected. For full-text screening, studies with models of NCDs that reported metabolic and neurological outcomes when treated with polyphenols were selected for inclusion in this review. RESULTS: 23 articles, using individual compound (11 articles) or polyphenols extracts (12 articles), were included in this review: 5 articles using tea polyphenols, 12 articles using grape-derived polyphenols, 3 articles using the polyphenol quercetin, and 3 articles using other polyphenol sources. Most results agree on the beneficial effect of polyphenols in attenuating alterations in energy balance and body weight. Such effects were associated with neuroprotective responses in different brain areas including hippocampus and hypothalamus. CONCLUSION: In conclusion, this review shows that the treatment with polyphenols, especially resveratrol or quercetin, attenuates the adverse effects of NCDs on energy balance and are associated with neuroprotective effects.

Studying work practices: a key factor in understanding accidents on the level triggered by a balance disturbance.

Accidents on the level (AOL) rank second amongst the most numerous and serious occupational accidents with days lost in France and are a major health and safety problem in every sector of activity. The case study described in this paper was conducted at a metallurgical company with 300 employees. The aims of this work were dual: 1) to extend the general knowledge required for preventing these accidents; 2) to propose prevention measures to this company. Existing data on company occupational accidents were gathered and analysed to identify a work situation that appeared likely to cause AOL. This work situation was analysed in detail. Several risk factors were identified within this work situation, by way of interviews with 12 operators. These risk factors concerned various dimensions of the work situation, particularly its physical dimension (e.g. templates structure) and organisational dimension (e.g. parts availability). Interviews were conducted, focusing on risk factors perceived by operators and involving allo-confrontations based on accounts of four AOL occurring in this situation. Allo-confrontations were interviews confronting operators with a risk occupational situation that was accidental for one of their colleagues, the latter being absent from the interview. Results highlighted the fact that the work practices implemented are key factors in understanding these accidents. This study underlines the role of work practices in AOL causality and prevention. It also provides explanations associated with various work situation dimensions involving adoption of more or less safe work practices. AOL are serious and frequent in occupational situations. Injury claims analysis and interviews in an industrial company emphasise the specific characteristics of an occupational situation and of prevention actions forming the basis of an intervention. The need for a better understanding of factors affecting work practice is highlighted in relation to research.

[Imaging networks, surgical simulation, computer-assisted neurosurgery]. / Réseaux d'imageurs, simulation chirurgicale, neurochirurgie guidée par ordinateur.

OBJECTIVE: In 1988, the neurosurgeons and neuroradiologists at the Val-de-Grâce hospital decided to create a stereotaxis site using advanced medical imaging date (CT-scan or MRI). METHODS: Two MRI machines and on CT unit were linked to a network (ETHERNET) available for radiologists in 1989. Neurosurgeons adapted stereotaxis sites using Leksell, Fisher and CRW software for MRI. A data processing program recognizing these sites was developed for stereotaxic biopsies based on MRI data. The network was extended in 1992 to the radiotherapy unit for multiple beam stereotaxic irradiations. Finally from 1994, when a computer-guided microscope (Zeiss MKM) was installed, nearly all neurosurgical procedures were conducted under stereotaxic conditions. RESULTS: Since 1989, approximately 900 computer-guided stereotaxic biopsies have been performed with precision in the millimeter range. Since 1994, the Zeiss MKM microscope has been used for 120 computer-guided procedures with the frameless stereotaxic technique guided from landmarks on the outer cranium or attached to the scalp. Mean precision obtained with landmarks was 1.2 mm and 2.8 mm with scalp markers. CONCLUSION: These techniques of computer-assisted neurosurgery based on advanced medical imaging techniques has been revolutionary for surgical approach to intracranial and intracerebral diseases. Smaller assess routes and precise pathways allow an approach to formerly inoperable lesions with minimal risk.

Activation of the hippocampal formation by vestibular stimulation: a functional magnetic resonance imaging study.

Functional MRI (f-MRI) is a non-invasive technique developed to permit functional mapping of the brain with a better temporal and spatial resolution than that offered by PET techniques. In our study, f-MRI was performed using blood oxygenation level dependent (BOLD) contrast imaging based on the magnetic properties of hemoglobin. This method relies on changes in the blood supply to the brain that accompany sensory stimulation or changes in cognitive state. All the images were obtained at 1.5 T on a Signa GEMS without ultrafast imaging. The vestibular stimulation was cold irrigation of the external auditory meatus (caloric stimulation). A population of normal healthy volunteers without a history of vestibular dysfunction was studied. The hippocampal formation as well as the retrosplenial cortex and the subiculum were activated by vestibular stimulation, suggesting that this activation may be related to spatial disorientation and a sensation of self-rotation experienced by the subjects during vestibular stimulation. The other results are similar to those obtained using PET.

Location of the human posterior eye field with functional magnetic resonance imaging.

The frontal eye field and parietal eye field are known to be involved during visually guided saccades. As the location of the human parietal eye field is not yet well known, functional MRI was used during such a saccade task to better localise this field. Besides activity in visual areas of the occipital cortex, bilateral activity was seen in the precentral sulcus, corresponding to the frontal eye field, and in the deep region of the intraparietal sulcus. It is suggested that this intraparietal area, bordering areas 39 and 40 of Brodmann, corresponds to the human parietal eye field.

[Magnetic resonance imaging and meningiomas of the posterior cerebral fossa. 31 cases]. / Imagerie par résonance magnétique et méningiomes de la fosse cérébrale postérieure. 31 cas.

To assess the value of MRI for meningioma of the posterior cerebral fossa, in correlation with surgical and pathological findings, we retrospectively reviewed 31 cases. The patients (24 females and 6 males ranging in age from 25 to 79 years) were preoperatively studies on a 1,5 T MR imager (GEMS Signa) between july 1989 and november 1993. The protocol included: 1. MR scan with axial sections in T2-weighted spin-echo sequence (3 mm thickness), T1-weighted spin-echo sequence before and after gadolinium injection (3-5 mm thickness), coronal and sagittal T1-weighted sections performed after injection. 2. Surgery reports. 3. Histopathological reports; the predominant histological subtype of each tumor was graded according to the classification scheme of Russel and Rubinstein. We focused on five items: 1. The site of the dural attachment of the meningioma. 2. Tumoral extensions (to the tentorium, to the jugular foramen, to the internal auditory canal). 3. The meningioma signal in T1- and T2-weighted sequence using the same visual scoring system for grading signal intensities as Elster and al. 4. Secondary features (necrosis, cysts, calcifications) within the tumor. 5. Interface between meningioma and encephalic structures. Meningiomas arose from the posterior surface of the petrous bone in 74% of the cases and from the clivus in 9.6%. Meningiomas were bulky at the time of diagnosis as since tumoral arrow overtook 2 cm in 64.5% of the cases. Surgical approach was guided by an anatomo-radiologic classification based on the exact site of tumoral dural attachment. This determination relied on: 1. Osseous reaction noted in 58% of the cases (enostosic spur in 19%, localized osseous thickening in 16%). 2. The trigeminal nerve displacement by the tumor; in case of clival meningioma extended to the petrous apex, this nerve is displaced outside; otherwise, meningioma of the petrous bone extended to the clivus displaced the trigeminal nerve inside. 3. Radiate structure within tumor converging to vascular basal pole of the meningioma noted in 42% of the cases. Tentorial involvement remained a difficult diagnosis on MR images. It was affirmed when the tumor extended on the opposing surface of the tentorium and when focal hypersignal existed through the usual tentorial hyposignal on T2-weighted images and T1-weighted images after gadolinium. On the other hand, tentorial linear dural enhancement adjacent to the tumor was not a reliable sign (error in 15.8% of the predicted cases). The meningothelial (syncitial) type was noted in 67.7% of the cases. (ABSTRACT TRUNCATED AT 450 WORDS)

[MRI aspects of progressive multifocal leukoencephalopathy]. / Aspects IRM de la leucoencéphalopathie multifocale progressive.

Progressive Multifocal Leukoencephalopathy is a demyelinating disease. MRI shows high signal intensity areas on T2w sequence and low intensity aeras on T1w sequence, without enhancement after intravenous contrast injection. The involvement of arcuate fiber (U fibers) creates a sharp border with the cortex. There is no mass effect. Involvement of parieto-occipital areas is frequent. The lesions may be uni or bilateral, single or multiple; bilateral lesions are asymmetric. This typical appearance on MR images occurs in 90% of the patients with PML. Some atypical patterns may occur: focal hemorrhage, atrophy, faint peripheral enhancement and involvement of deep gray matter (basal ganglia). In most cases, the clinical and MR features provide the diagnosis. The main differential diagnosis, in MRI, is HIV-leukoencephalitis, but lesions are diffuse, less intense on T2w sequence and not visible on T1, without involvement of the arcuate fibers. Stereotactic biopsy should be performed only for atypical lesions, particularly in case of predominant involvement of deep gray structures.

[MRI of the internal auditory meatus. Is injection of gadolinium indispensable?]. / IRM du méat auditif interne. L'injection de gadolinium est-elle indispensable?

OBJECT: To compare prospectively high resolution fast spin echo T2 weighted (FSE-T2W) images and gadolinium-enhanced spin echo T1 weighted images for diagnosis of pathology of the internal auditory meatus (IAM). PATIENTS AND METHODS: 114 patients underwent MR imaging at 1.5 T with the following protocol: axial images; whole brain FSE-T2W sequence (256 matrix); 2 sequences focused on IAM with high resolution FSE-T2W acquisitions (512 matrix, 3 mm sections with 1.5 mm overlapping); pre and postcontrast T1 weighted sequences focused on IAM. Examinations were viewed by senior neuroradiologists. RESULTS: 31 lesions were detected in the IAM by high resolution FSE-T2W images; 25 lesions were found in the IAM by postcontrast T1 weighted images, i.e. 6 false-positive results and none false-negative. On the basis of 228 studied IAMs the sensitivity, specificity and negative predictive value of this high resolution FSE-T2W sequence were 100%, 97% and 100% respectively. CONCLUSION: Gadolinium enhanced sequence is not indispensable if high resolution FSE-T2W images are normal. Gadolinium-enhanced sequence remains essential in others equivocal cases (difficult diagnosis or abnormal IAM).

Imaging of the vestibule.

PURPOSE: State-of-the-art imaging of the normal and pathologic vestibule. METHODS AND MATERIAL: This study is based on the experience of three French imaging centers (Val de Grâce, Bégin, and Saint-Antoine hospitals) working with 1- and 1.5-tesla magnetic resonance units and high-resolution computed tomography, and it includes a review of the literature. Computed tomography is performed with a high-resolution program, matrix 512 x 512, field of view 9.6 cm, joined 1-mm section, overlapped sections every 0.5 mm, axial and coronal sections, or reformatted images. High-resolution magnetic resonance imaging (matrix 512 x 384), field of view 18 cm, is used with fast T2-weighted sequences (sections 3 or 2 mm thick, constructive interference in steady state, T2-weighted gradient echo sequence three-dimensional Fourier transformation). A joined section of 0.7 mm in any direction is obtained if necessary. Superimposition of computed tomography and magnetic resonance imaging with a stereotactic technique by identification of identical anatomic points is sometimes used. RESULTS: We review the interest and place of computed tomography and magnetic resonance imaging in the diseases of the labyrinth and internal auditory canal related to abnormal vestibular functions: inflammatory labyrinthitis, vestibular hemorrhages, sclerosing and ossifying labyrinthitis, traumatism, malformations, perilymphatic fistulas, otosclerosis, tumors, cochleovestibular neuritis, and hydrops of the endolymphatic system.

[High resolution T2 weighted MRI sequence and diagnosis of neurinoma of the VIII]. / IRM en séquence pondérée T2 haute résolution et diagnostic des neurinomes du VIII.

OBJECT: To assess the value of high resolution fast spin echo T2 weighted (HR-FSE T2w) sequence for the diagnosis of acoustic neuroma. Two criteria for normality of the HR-FSE T2w examination are defined. PATIENTS AND METHODS: 114 patients underwent MR imaging at 1.5 T. The protocol included: axial images; 2 overlapped sequences focused on the internal auditory meatus (IAM), HR-FSE T2w acquisition (512 matrix, 3 mm sections with 1.5 mm overlapping); pre and postcontrast T1 weighted sequences focused on IAM. We defined two criteria for a normal HR-FSE T2w image: cerebellospinal fluid visible throughout the IAM, cochleo-vestibular and facial nerves visible in the IAM. RESULTS: 31 examinations were abnormal with HR-FSE T2w sequence, 25 lesions were found on postcontrast T1 weighted sequence (i.e. 6 false-positive results and none false-negative). The sensitivity, specificity and negative predictive value of this HR-FSE T2w sequence were 100%, 97% and 100% respectively. CONCLUSION: the HR-FSE T2w sequence is the first-line method for detecting tumoral lesions of the IAM. If the 2 normality criteria are present on the HR-FSE T2w images, the T1w sequence with gadolinium injection is of no use; the injection of gadolinium remains necessary if only one of these criteria is lacking.

[A technique of MRI signal processing for functional imaging]. / Une technique de traitement du signal en IRM pour l'imagerie fonctionnelle.

Recent works show the possibility of MRI to study brain functionalities. Today, treatment relies essentially on addition and subtraction of images accumulated during rest and activity periods. But this technic is not discriminating and we have developed a software to see and treat images with filtering algorithm and statistical analysis of signal. The first results are given. Perfections are possible and are being realized.

[Reformatting 3-dimensional medical images. Application to MRI and scanners]. / Recalage d'images médicales tridimensionnelles. Application à l'IRM et au scanner.

Several kinds of images, each giving a different information, are now available to radiologists. The MRI images have excellent contrast resolution and enable soft tissues to be differentiated, but they do not distinguish structures with low water content, notably air and bone, whereas these are easily recognized by CT. The aim of this study is to present a simple, entirely radiologist-supervised method to examine the radiological data of any patient, obtained from several kinds of images. MRI is performed using a GEMS Signa, 1.5 Tesla, 4.9 version magnet. Acquisitions are T1- or T2-weighted spin-echo or gradient sequences, with a 256 or 512 matrix, on axial sections, with of without contrast injection. CT is performed using a GEMS Hi Speed scanner. Acquisitions are obtained on a 512 matrix and with a "Soft" or "Bone" filter, without contrast injection. The two series of sections are transmitted, through an Etherne network, to a Sun console where the two corresponding volumes are reconstructed on a GEMS Voxtol by means of a 3-dimensional soft ware for image treatment. At least 3 couples define the rotation and translation required for one of the two volumes to reset it in the guide mark of the other. The soft ware then looks for the best transformation, in terms of least square, between the two 3-dimensional volumes. The calculation demands only a few seconds. One of the two objects is then recalculated in the guide mark of the other. The cursor positioned by the user on any point of the object is linked to a second cursor which will automatically position itself on the corresponding point of the other object. The accuracy obtained (about one millimeter) is specified by the soft ware which indicates how to improve resetting. In addition to its teaching value, this superimposition image can help in the diagnosis and can be used for surgical stimulation because it is possible to mix the images. This mixing gives access to a new type of imaging, since the images spared can be reconstructed in volume, and treated in all planes, as a CT or MRI examination. The term "Anatomical Reconstruction Images" may be suggested for this new type of examination. Beside intermodal comparison, one may also imagine that the soft ware can be used to follow up the patient over time (repeat MRI) or to make comparisons between several objects, although the elastic resetting method is more often appropriate in the second case.

[Stereotaxy in MRI]. / La stéréotaxie en IRM.

The first biopsy in Val-de-Grâce has been performed in 1987, under CT alone, with a Leksell frame. 150 punctures have been performed for a diagnostic or a therapeutic goal. Since 1990, stereotaxy is performed under MRI. 320 punctures have been made with 1.9% mortality and 1.3% morbidity. The future of stereotactic technics is therapeutic: precision of surgery (vascular malformation, neurogenous tumor, deep tumor), precision of radiotherapy, new anti-tumoral treatments.

[Progressive multifocal leukoencephalopathy localized in the thalamic grey matter in an AIDS-patient]. / Leuco-encéphalopathie multifocale progressive localisée en substance grise thalamique chez un patient atteint de SIDA.

Involvement of the deep grey matter is unusual in Progressive Multifocal Leukoencephalopathy (PML), which is disease of the white matter. Basal ganglia involvement is usually secondary to extension from lesions of adjacent white matter and easy to recognize. We report a biopsy-proven case of PML in which lesions were mainly thalamic.

[Cholesteatoma of the posterior cerebral fossa. 7 cases and review of the literature]. / Cholestéatomes de la fosse cérébrale postérieure. Sept observations et revue de la littérature.

Fifty percent of intracranial epidermoid cysts are located in the cerebral posterior fossa. Clinical presenting features are not specific and vary according to cyst topography and mass effect on neighbouring structures. In CT, the lesion is hypodense as related to the cerebral tissue, but with no specificity. In MRI, the typical form shows quasi-pathognomonic morphologic characters with polyedric contours, a marble aspect, a reduced mass effect as compared to the tumor volume and an evolution signal close to that of cerebrospinal fluid, with no increase after contrast agent injection. Some primary cholesteatomas have a different radiological aspect. They can be hyperdense in CT and have a spontaneous hyperintense signal in T1-weighted MRI sequence. They correspond to complicated epidermoid cysts associated with hemorrhages and granulomatous meningeal reaction whose constitution is very very close to that of cholesterine granulomas.

[Ocular complications of intracarotid chemotherapies with nitrosourea agents]. / Complications oculaires des chimiothérapies intracarotidiennes par nitroso-urées.

The authors report ocular complications in intracarotid chemotherapy with Nitrosyl-urea on 39 patients with intracerebral malignant tumor (anaplastic astrocytoma). Internal carotid infusion catheter was in infra-ophthalmic position. They also report 13 ocular complications (33% of cases) as arterial retinal occlusions essentially, ipsilateral to catheter site. Their study and literature revue emphasize five ocular toxicity factors; intracarotid catheter position, type of drug, its quantity, its solubility and solvent, the rate of infusion.

[Primary brain lymphoma in AIDS. 17 cases studied by MRI before stereotaxic biopsies]. / Lymphome cérébral primitif du SIDA. 17 cas explorés en IRM avant biopsie stéréotaxique.

AIM: Determining which semiological criteria might help to suggest lymphoma when an intracerebral mass in observed in a patient with AIDS. The use of these criteria might shorten the duration of the anti-toxoplasmic test treatment and to perform puncture earlier. The fast growth of the lymphomas may account for the rapid death of these patients if untreated, but as a corollary, its increase in size can be objectively measured over a short period, about ten days. MEANS: Retrospective study of 17 lymphomas diagnosed with stereotaxic puncture. RESULTS: The most discriminating criteria are ventricular encasement or an original site in the white matter, as well as the moderate character of the edema and of the mass effect relative to the volume of the tumor. Other arguments also help: simple lesion, large size, sinuous contour, no signs of hemorrhage. CONCLUSION: The diagnosis of lymphoma can often be proposed at once. A control must then be performed very soon, with stereotaxic puncture if the volume of the lesion has increased in the meantime.

[Stereotaxy, MRI and independent computer. 85 punctures]. / Stéréotaxie, IRM et console indépendante. 85 ponctions.

After 150 stereotactic biopsy with CT, the team of Val-de-Grâce has made these ones with MRI and simulation of the complete procedure with an independent computer. The result of 85 biopsies is reported. This one imply the acquisition of 3DFT millimetrics slices, the transfer by Ethernet network on a computer where a specific software treat the data and allow to establish the better course for the needle biopsy. The constraints of quality are very important and some test must be executed. The diagnosis are established, avoiding an unless trepanation.

[Relations between neurinoma of the VIII cranial nerve and the porus of the internal auditory meatus. Apropos of 110 cases]. / Rapports du neurinome du VIII avec le porus du conduit auditif interne (CAI). A propos de 110 cas.

110 cases of neurinomas of the VIIIth with APC extension (104 patients) were studied using MRI or CT. Classically, it is said that the tumoral mass is centered on the IAC. In our study, among 110 cases of neurinomas, only 9 were centered along the axis of IAC on axial slices and only 23 on coronal slices. The anterior development of the tumor is never more than 1 cm, except in 3 cases of large and multicystic neurinoma. We suggest that the anterior development of large tumors is limited by the VIIth nerve.