Food toxins and the Caribbean Parkinson plus types.

In the 90's, clinico pathological studies have considerably improved the diagnosis of specific and rare neurodegenerative diseases. After a training in Parkinsons' disease in Paris, the author moved to French West Indies (Guadeloupe) and observed a high incidence of atypical parkinsonism with dementia, unresponsive to levodopa. Similar features were observed in Martinique. An environmental origin has been suspected with the exposure to toxins of annonaceae leaves and seeds. The candidate toxins are acetogenins acting as mitochondrial poison. This was demonstrated in neuronal cell cultures, and in animals. However, the agency for food security did not conclude that Annonaceae should not be used for herbal (medicinal) tea, even if the population is now aware about the possible risk of parkinsonism after exposure to annonaceae acetogenins.

Post-mortem 7.0-tesla magnetic resonance study of cortical microinfarcts in neurodegenerative diseases and vascular dementia with neuropathological correlates.

BACKGROUND: Until recently cortical microinfarcts (CMIs) were considered as the invisible lesions in clinical-radiological correlation studies that rely on conventional structural magnetic resonance imaging. The present study investigates the presence of CMIs on 7.0-T magnetic resonance imaging (MRI) in post-mortem brains with different neurodegenerative and cerebrovascular diseases. MATERIALS AND METHODS: One hundred-seventy five post-mortem brains, composed of 37 with pure Alzheimer's disease (AD), 12 with AD associated to cerebral amyloid angiopathy (AD-CAA), 38 with frontotemporal lobar degeneration, 12 with amyotrophic lateral sclerosis, 16 with Lewy body disease (LBD), 21 with progressive supranuclear palsy, 18 with vascular dementia (VaD) and 21 controls were examined. According to their size several types of CMIs were detected on 3 coronal sections of a cerebral hemisphere with 7.0-T MRI and compared to the mean CMI load observed on histological examination of one standard separate coronal section of a cerebral hemisphere at the level of the mamillary body. RESULTS: Overall CMIs were significantly prevalent in those brains with neurodegenerative and cerebrovascular diseases associated to CAA compared to those without CAA. VaD, AD-CAA and LBD brains had significantly more CMIs compared to the controls. While all types of CMIs were increased in VaD and AD-CAA brains, a predominance of the smallest ones was observed in the LBD brains. CONCLUSIONS: The present study shows that 7.0-T MRI allows the detection of several types of MICs and their contribution to the cognitive decline in different neurodegenerative and cerebrovascular diseases.

Iron deposits in post-mortem brains of patients with neurodegenerative and cerebrovascular diseases: a semi-quantitative 7.0 T magnetic resonance imaging study.

BACKGROUND AND PURPOSE: Accumulation of iron (Fe) is often detected in brains of people suffering from neurodegenerative diseases. However, no studies have compared the Fe load between these disease entities. The present study investigates by T2*-weighted gradient-echo 7.0 T magnetic resonance imaging (MRI) the Fe content in post-mortem brains with different neurodegenerative and cerebrovascular diseases. METHODS: One hundred and fifty-two post-mortem brains, composed of 46 with Alzheimer's disease (AD), 37 with frontotemporal lobar degeneration (FTLD), 11 with amyotrophic lateral sclerosis, 13 with Lewy body disease, 14 with progressive supranuclear palsy, 16 with vascular dementia (VaD) and 15 controls without a brain disease, were examined. The Fe load was determined semi-quantitatively on T2*-weighted MRI serial brain sections in the claustrum, caudate nucleus, putamen, globus pallidus, thalamus, subthalamic nucleus, hippocampus, mamillary body, lateral geniculate body, red nucleus, substantia nigra and dentate nucleus. The disease diagnosis was made on subsequent neuropathological examination. RESULTS: The Fe load was significantly increased in the claustrum, caudate nucleus and putamen of FTLD brains and to a lesser degree in the globus pallidus, thalamus and subthalamic nucleus. In the other neurodegenerative diseases no Fe accumulation was observed, except for a mild increase in the caudate nucleus of AD brains. In VaD brains no Fe increase was detected. CONCLUSIONS: Only FTLD displays a significant Fe load, suggesting that impaired Fe homeostasis plays an important role in the pathogenesis of this heterogeneous disease entity.

Superficial siderosis of the central nervous system: a post-mortem 7.0-tesla magnetic resonance imaging study with neuropathological correlates.

BACKGROUND: Superficial siderosis (SS) is a rare finding on T2*-weighted magnetic resonance imaging (MRI), regarded as a radiological marker of cerebral amyloid angiopathy (CAA). The present study investigates with 7.0-tesla MRI the prevalence of SS and its underlying pathological substrate in a consecutive series of post-mortem brains of elderly patients with various neurodegenerative and cerebrovascular lesions. MATERIALS AND METHODS: The prevalence of SS and associated lesions was screened using 7.0-tesla MRI and their neuropathological correlates in 120 post-mortem brains of patients with various neurodegenerative and cerebrovascular diseases. RESULTS: Eighty-three separate zones of SS were detected in 45 brains (37.5%), including 25 areas of disseminated SS (dSS) and 58 areas of focal SS (fSS), restricted to less than 3 sulci. dSS was spatially related to sequels of 14 lobar haematomas and 11 cerebral infarcts, while fSS was connected to 19 microbleeds and 39 micro-infarcts (p < 0.001). Comparison of the 15 CAA to the 30 non-CAA brains showed that dSS was due to an old lobar haematoma in 53% of the former group compared to 3% of the latter group (p = 0.003). fSS was due to a microbleed in 7% of the CAA brains and to 40% of the non-CAA brains (p = 0.03). CONCLUSIONS: SS is associated with both haemorrhagic and ischaemic underlying lesions. It is frequently observed on T2*-weighted 7.0-tesla MRI, and two types of SS may be described. Clinicians should keep in mind that SS may be found in other settings than CAA.

Hippocampal microbleed on a post-mortem t(2)∗-weighted gradient-echo 7.0-tesla magnetic resonance imaging?

The present post-mortem study of a brain from an Alzheimer patient showed on a T(2)∗-weighted gradient-echo 7.0-T MRI of a coronal brain section a hyposignal in the hippocampus, suggesting a microbleed. On the corresponding histological examination, only iron deposits around the granular cellular layer and in blood vessel walls of the hippocampus were observed without evidence of a bleeding. This case report illustrates that the detection of microbleeds on MRI has to be interpreted with caution.

Tauopathies with parkinsonism: clinical spectrum, neuropathologic basis, biological markers, and treatment options.

Tauopathies with parkinsonism represent a spectrum of disease entities unified by the pathologic accumulation of hyperphosphorylated tau protein fragments within the central nervous system. These pathologic characteristics suggest shared pathogenetic pathways and possible molecular targets for disease-modifying therapeutic interventions. Natural history studies, for instance, in progressive supranuclear palsy, frontotemporal dementia with parkinsonism linked to chromosome 17, corticobasal degeneration, and Niemann-Pick disease type C as well as in amyotrophic lateral sclerosis/Parkinson-dementia complex permit clinical characterization of the disease phenotypes and are crucial to the development and validation of biological markers for differential diagnostics and disease monitoring, for example, by use of neuroimaging or proteomic approaches. The wide pathologic and clinical spectrum of the tauopathies with parkinsonism is reviewed in this article, and perspectives on future advances in the understanding of the pathogenesis are given, together with potential therapeutic strategies.

[Neuroradiological aspects of Devic's neuromyelitis optica]. / La neuromyélite optique rémittente: données neuroradiologiques.

INTRODUCTION: Neuromyelitis optica (NMO) is a rare inflammatory and demyelinating disorder of the central nervous system, restricted to optical nerves and spinal cord. The main neuroradiological aspects, now summarized into a complete set of diagnosis criteria, are a normal cerebral MRI at onset and longitudinal involvement of the spinal cord concerning more than 3 vertebral segments. The clinical course and frequency of typical lesions remain unknown. OBJECTIVE: We here report neuroradiological data from patients suffering from NMO. METHODS: Brain and spinal cord MRI were systematically reviewed for 32 afro-Caribbean patients. RESULTS: A typical longitudinal spinal lesion was seen in 44.7 percent with or without edema; a lesion involving less than 3 vertebral segments in 26.3 percent and no lesion in 21.1 percent. Longitudinal study of a few bouts suggested a progressive normalisation of spinal cord appearance. Atrophy was negatively correlated with immunosuppressive treatment. Cerebral lesions usually absent at onset were correlated to the follow-up. In a non-recursive condition, patients completed diagnostic criteria for encephalic and spinal lesions in 82.8 percent and 48.1 percent. CONCLUSION: Radiology of spinal bouts showed multiple aspects besides the typical form. The notion of multiple bouts must be added to the spinal criteria to achieve good sensitivity. A typical extensive spinal lesion is usual in the follow-up, but seen after less then half of the bouts. Requiring such a lesion would delay the diagnosis.

[Preliminary pilot study of cyproterone acetate for the treatment of aggressive behavior associated with severe dementia]. / Etude pilote préliminaire de l'acétate de cyprotérone dans les comportements agressifs associés aux démences sévères.

INTRODUCTION: Behavioral symptoms are common in dementia, and seem to be more frequent in men than in women. Agitation is frequently responsible for caregiver burn-out and leads to institutionalization. The dramatic increase in the prevalence of Alzheimer's disease and related disorders requires better management of behavior symptoms. Although environmental adaptation has been proposed recently, for many years, psychoactive medications and physical restraints were the primary approach. However, in severely demented patients, both pharmacologic and non-pharmacologic treatments are inoperative. In this situation, alternative pharmacologic approach should be tested. Cyproterone acetate, an antiandrogen and progestative steroid has never been proposed to prevent aggressive behavior in dementia, but its favorable effect is well described in rat and monkey aggressivity. PATIENTS AND METHODS: Cyproterone acetate was proposed for 19 demented patients who developed severe aggressive behaviors or an agitation unresponsive to psychoactive drugs (even in association) or to environmental adaptation. Clinical and behavioral analysis was carried out using the Cohen-Mansfield agitation inventory associated with an assessment of dependency in daily life activities, before and during treatment with cyproterone acetate. The behavioral status was stable, with permanent or repetitive agitation. Seven patients had vascular dementia, 7 had Alzheimer's disease, 2 had fronto-temporal degeneration, 2 had Huntington's disease and 1 a probable diffuse Lewy bodies disease. Fifteen patients had prominent aggressive behavior and 4 had predominant aberrant motor behavior with aggressive behavior. RESULTS: Cyproterone (50 to 100mg - mean: 92.5mg daily) improved significantly aggressive and impulsive behavior related to Alzheimer's disease or vascular dementia but had no effect on aberrant motor behavior. When cyproterone was stopped, aggressive behaviors reappeared more rapidly in vascular dementia. CONCLUSION: Cyproterone acetate is then an interesting choice when aggressive behavior is not improved with psychotropic drugs. A detailed clinical analysis is required to avoid the use of cyproterone in non-aggressive and non-impulsive patients. The results of this preliminary study suggest a randomized double-blind study should be carried out in the near future. The behavior improvement could be related to the blockage of androgen receptors, and simultaneously to the sedative effect of progestative drugs.

Role of return migration in the emergence of multiple sclerosis in the French West Indies.

The emergence of multiple sclerosis in island societies has been investigated only in a few Caucasian populations living in temperate regions. The effect of human migration on the risk of developing this disease is still an open question because of possible genetic selection. We conducted an epidemiological study of the multiple sclerosis population in the French West Indies (Martinique and Guadeloupe), a population which includes large numbers of West Indians who have returned after emigrating to metropolitan France. Standardized incidence ratios (SIRs) for multiple sclerosis among migrants were calculated and their genetic characteristics were compared to those of non-migrants. The crude prevalence of multiple sclerosis was 14.8/10(5) on December 31, 1999 (95% CI: 11.9-17.7); and its crude mean annual incidence for the period July 1, 1999 to June 30, 2002 was 1.4/10(5) (95% CI: 1.0-1.8), confirming its emergence in the French West Indies. Recurrent neuromyelitis optica, which is virtually the only form of multiple sclerosis in black African populations in tropical regions, represented not >17.8% of these cases. During the 1,440,000 person-years of follow-up, 33 incidence cases were identified in migrants. Since the number of expected cases was 19.3, the overall SIR was 1.71 (95% CI: 1.19-2.38; P < 0.01) among migrants. The increase in the SIR was more marked if the stay was made before the age of 15 years (4.05, 95% CI: 2.17-6.83; P < 0.0001). European ancestry in the two migrating and non-migrating populations was similar. Martinique, which has a higher rate of return migration, has a higher prevalence of multiple sclerosis (21.0/10(5) versus 8.5/10(5)) and a higher incidence (2.0/10(5) versus 0.7/10(5)) than Guadeloupe. The emergence of the disease in the French West Indies is of environmental rather than genetic origin. It may be explained either through the introduction by migrants of precipitating environmental factors that operate in a critical way before the age of 15 years, and/or by the recent disappearance from the French West Indies of protective environmental factors acting before this age.

Bipallidal haemorrhage after ethylene glycol intoxication.

Acute or subacute bipallidal lesion, an uncommon radiological feature produced by metabolic disorders or poisoning, has never been attributed to ethylene glycol (EG) intoxication. This 50-year-old Afro-Caribbean alcoholic man had unexplained loss of consciousness. Blood tests showed osmolar gap. Drug screening was positive for EG at 6.06 mmol/l. Brain CT revealed bilateral pallidal haemorrhage. Pallidal haematoma, which could be related to deposition of oxalate crystals issued from EG metabolism, should lead to toxicological screening.

[Wernicke-Korsakoff syndrome: diagnostic contribution of magnetic resonance imaging]. / Encéphalopathie de Gayet-Wernicke: intérêt diagnostique et pronostique de l'Imagerie par Résonance Magnétique.

Data regarding the magnetic resonance imaging (MRI) features in Wernicke-Korsakoff syndrome (WKS) are scarce. WKS usually combines a cerebellar syndrome, oculomotor disorder and confusion. The aim of this study was to determine more precisely the clinical presentation of WKS and the frequency and topography of MRI abnormalities. Furthermore, we try to assess the prognostic value of both clinical signs and MRI abnormalities. We retrospectively studied 25 patients with WKS in which an MRI was available. We assessed the initial clinical presentation and the outcome. We also analyzed the frequency and the location of MRI lesions. We then correlated clinical and MRI data with the clinical outcome. Eleven patients (44 p. 100) had the full WKS. Fourteen of the 25 patients (56 p. 100) had a poor evolution. The occurrence of full WKS was correlated with a poor outcome (p < 0.02). Signal abnormalities on T2-weighted images were found in the periacqueducal region, in the thalami or in the mamillar bodies in 16 cases (64 p. 100). There was a correlation between an hypersignal in at least one region and a poor clinical outcome (p < 0.02). Our study demonstrates the high frequency of brain MRI lesions in WKS and the correlation of both initial clinical signs and MRI abnormalities with a poor clinical outcome.

Risk factors associated with ischaemic stroke in Guadeloupe

We carried out a case control study at the University Hospital of Pointe-Ó-Pitre, Guadeloupe, during eight months. Seventy patients with ischaemic stroke and seventy age- and sex-matched controls were involved. A standard questionnaire reported clinical characteristics and medical history. Seventy-six per cent of patients suffered from hypertension. Obesity and diabetes were more frequent in the case group than in the control group. Serum creatinine concentration (86 vs 74 mumol/l; p < 0.001), total cholesterol (5.9 vs. 5.2 mmol/l; p < 0.001), apolipoprotein B (1.2 vs 1.0 g/l; p < 0.001) and lipoprotein (a) (82 vs 48 mg/dl; p < 0.001) were significantly higher in patients than controls. Multiple logistic regression analysis revealed that in addition to serum creatinine, serum apolipoprotein B, hypertension, obesity, serum lipoprotein (a) and diabetes mellitus were associated independently and significantly with ischaemic stroke. These findings have implications for clinical practice and further research particularly with respect to serum creatinine concentration as a marker of renal damage from hypertension and as a risk factor itself for cerebrovascular disease.

Risk factors associated with ischaemic stroke in Guadeloupe

We carried out a case control study at the University Hospital of Pointe-a-Pitre, Guadeloupe, during eight months. Seventy patients with ischaemic stroke and seventy age- and sex matched controls were involved. A standard questionnaire reported clinical characteristics and medical history. Seventy-six per cent of patients suffered from hypertension. Obesity and diabetes were more frequent in the case group than in the control group. Serum creatinine concentration (86 vs 74umol/l; p <0.001), total cholesterol (5.9 vs 5.2 mmol/l; p < 0.001), apolipoprotein B (1.2 vs 1.0 g/l' p < 0.001) and lipoprotein (a) (82 vs 48 mg/dl; p< 0.001) were significantly higher in patients than controls. Multiple logistic regression analysis revealed that in addition to serum creatinine, serum apolipoprotein B, hypertension, obesity, serum lipoprotein (a) and diabetes mellitus were associated independently and significantly with ischaemic stroke. These findings have implications for clinical practice and further research particularly with respect to serum creatinine concentration as a marker of renal damage from hypertension and as risk factor itself for cerebrovascular disease.(Au)

[Chronic intracerebral stimulation and abnormal movements: why and when? Major therapeutic advances in the 90s]. / Stimulation intracérébrale chronique et mouvements anormaux: pourquoi et comment? Une avancée thérapeutique majeure des années 90.

TECHNICAL ASPECTS: Surgical procedures for abnormal movements progressively evolved toward microinvasive techniques performed under stereotaxic control. The next advance was the development of well-tolerated intracerebral stimulation with reversible effects. The quality of the results depends on optimal definition of the stimulation target. Optimally, the surgical protocol includes stereotaxic ventriculography to identify targets followed by electrical activity recordings of the structures crossed by the electrode. Finally, a minute study of the stimulation effects is performed under sterotaxic control while the patient is awake. PARKINSON'S DISEASES: Indications for thalamic stimulation in Parkinson's disease have given way to subthalamic stimulation which improves tremor, bradykinesia and rigidity simultaneously. This result confirms the implication of the subthalamic nucleus in the pathogenesis of Parkinson syndromes. The palladium may be stimulated in Parkinson's patients with major iatrogenic involuntary movements. ESSENTIAL TREMOR: Thalamic stimulation is indicated for essential tremor. The efficacy of chronic stimulation is currently under evaluation in other indications.

Risk factors associated with ischaemic stroke in Guadeloupe.

We carried out a case control study at the University Hospital of Pointe-à-Pitre, Guadeloupe, during eight months. Seventy patients with ischaemic stroke and seventy age- and sex-matched controls were involved. A standard questionnaire reported clinical characteristics and medical history. Seventy-six per cent of patients suffered from hypertension. Obesity and diabetes were more frequent in the case group than in the control group. Serum creatinine concentration (86 vs 74 mumol/l; p < 0.001), total cholesterol (5.9 vs. 5.2 mmol/l; p < 0.001), apolipoprotein B (1.2 vs 1.0 g/l; p < 0.001) and lipoprotein (a) (82 vs 48 mg/dl; p < 0.001) were significantly higher in patients than controls. Multiple logistic regression analysis revealed that in addition to serum creatinine, serum apolipoprotein B, hypertension, obesity, serum lipoprotein (a) and diabetes mellitus were associated independently and significantly with ischaemic stroke. These findings have implications for clinical practice and further research particularly with respect to serum creatinine concentration as a marker of renal damage from hypertension and as a risk factor itself for cerebrovascular disease.

[The effect of thalamic stimulation on levodopa induced dyskinesias--evaluation of a new target: the center parafascicular median]. / Effet de la stimulation thalamique sur les dyskinésies induites par la L-Dopa--évaluation d'une cible nouvelle: le centre médian parafasciculaire.

After 10 years of clinical practice (1987-1997), chronic thalamic deep brain stimulation (DBS) is considered to be effective in the treatment of drug-resistant parkinsonian tremor. DBS has produced few side-effects, which are usually reversible. More recently, DBS has been applied to other movement disorders (akinesia and rigidity, dyskinesias, dystonia), using new targets: internal pallidum, subthalamic nucleus. These targets have been selected on the basis of neurophysiological or anatomo-clinical data suggesting they could be effective. Control of L-Dopa peak-dose dyskinesias by thalamic ventralis intermedius nucleus (V.im.) stimulation has been reported by the Lille team, but not by the Grenoble team. We therefore re-examined all teleradioanatomical data of both teams, and compared them with the therapeutic effects. Location of 99 monopolar electrodes of thalamic stimulation, applied to treat parkinsonian tremor, has been retrospectively measured. The Lille team included 21 patients (22 electrodes); the Grenoble team included 52 patients (74 electrodes). L-Dopa dyskinesias were suppressed in all 9 patients in Lille, and improved clearly in only 8 out of 32 patients in Grenoble. The mean center of electrodes was significantly different between both teams, being deeper, more posterior and medial in Lille. This did not correspond to the coordinates of the V.im., but seems to be closer to those of the centromedian and parafascicular complex (CM-Pf), according to stereotactic atlases. Considering only the dyskinetic patients, the therapeutic effects on L-Dopa dyskinesias were related to the differences observed in the electrode position, but not to the team membership. Improvement of L-Dopa dyskinesias was significantly associated with deeper and more medial placement of electrodes. Retrospective analysis of ventriculographic data confirmed that the electrode position and therapeutic effects of DBS are strongly related. Our study suggested that CM-Pf stimulation could control both tremor and L-Dopa dyskinesias. This hypothesis is consistent with neuro-anatomical data showing that CM-Pf is connected to internal pallidum, the stimulation of which controls specifically L-Dopa dyskinesias.